Joe J. Landsberg; Kurt H. Johnsen; Timothy J. Albaugh; H. Lee Allen; Steven E. McKeand
2001-01-01
3-PG is a simple process-based model that requires few parameter values and only readily available input data. We tested the structure of the model by calibrating it against loblolly pine data from the control treatment of the SETRES experiment in Scotland County, NC, then altered the fertility rating to simulate the effects of fertilization. There was excellent...
Liang Wei; Marshall John; Jianwei Zhang; Hang Zhou; Robert Powers
2014-01-01
Models can be powerful tools for estimating forest productivity and guiding forest management, but their credibility and complexity are often an issue for forest managers. We parameterized a process-based forest growth model, 3-PG (Physiological Principles Predicting Growth), to simulate growth of ponderosa pine (Pinus ponderosa) plantations in...
NASA Astrophysics Data System (ADS)
Wei, L.; Marshall, J. D.
2007-12-01
3PG (Physiological Principles in Predicting Growth), a process-based physiological model of forest productivity, has been widely used and well validated. Based on 3PG, a 3PG-δ13C model to simulate δ13C content in plant tissue is built in this research. 3PG calculates carbon assimilation from utilizable absorbed photosynthetically active radiation (PAR), and calculates stomatal conductance from maximum canopy conductance multiplied by physiological modifier which includes the effect of water vapor deficit and soil water. Then the equation of Farquhar and Sharkey (1982) was used to calculate δ13C content in plant. Five even-aged coniferous forest stands located near Clarkia, Idaho (47°15'N, 115°25'W) in Mica Creek Experimental Watershed, were chosen to test the model, (2 stands had been partial cut (50% canopy removal in 1990) and 3 were uncut). MCEW has been extensively investigated since 1990 and many necessary parameters needed for 3PG are readily available. Each of these sites is located near a UI Meteorological station, which recorded half-hourly climatic data since 2003. These site-specific climatic data were extend to 1991 by correlating with data from a nearby SNOTEL station (SNOwpack TELemetry, NRCS, 47°9' N, 116°16' W). Forest mensuration data were obtained form each stand using variable radius plots (VRP). Three tree species, which consist more than 95% of all trees, were parameterized for 3PG model, including: grand fir (Abies grandis Donn ex D. Don), western red cedar (Thuja plicat Donn ex D. Don a) and Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco). Because 4 out of 5 stands have mixed species, we also used parameters for mixed stands to run the model. To stabilize, the model was initially run under average climatic data for 20 years, and then run under the actual climatic data from 1991 to 2006. As 3PG runs in a monthly time step, monthly δ13C values were calculated first, and then yearly values were calculated by weighted averages. For testing the model, tree cores were collected from each stand and species. Ring-widths of tree cores were measured and cross-dated with a ring-width chronology obtained from MCEW. δ13C contents of tree- ring samples from known year were tested. Preliminary results indicate 3PG-δ13C simulated values are consistent with observed values in tree-rings. δ13C values of modeled species are different: western red cider has the highest delta13C values among the three species and western larch has the lowest.
GPP in Loblolly Pine: A Monthly Comparison of Empirical and Process Models
Christopher Gough; John Seiler; Kurt Johnsen; David Arthur Sampson
2002-01-01
Monthly and yearly gross primary productivity (GPP) estimates derived from an empirical and two process based models (3PG and BIOMASS) were compared. Spatial and temporal variation in foliar gas photosynthesis was examined and used to develop GPP prediction models for fertilized nine-year-old loblolly pine (Pinus taeda) stands located in the North...
Brouwers, Melissa C; Makarski, Julie; Kastner, Monika; Hayden, Leigh; Bhattacharyya, Onil
2015-03-15
Practice guideline (PG) implementability refers to PG features that promote their use. While there are tools and resources to promote PG implementability, none are based on an evidence-informed and multidisciplinary perspective. Our objectives were to (i) create a comprehensive and evidence-informed model of PG implementability, (ii) seek support for the model from the international PG community, (iii) map existing implementability tools on to the model, (iv) prioritize areas for further investigation, and (v) describe how the model can be used by PG developers, users, and researchers. A mixed methods approach was used. Using our completed realist review of the literature of seven different disciplines as the foundation, an iterative consensus process was used to create the beta version of the model. This was followed by (i) a survey of international stakeholders (guideline developers and users) to gather feedback and to refine the model, (ii) a content analysis comparing the model to existing PG tools, and (iii) a strategy to prioritize areas of the model for further research by members of the research team. The Guideline Implementability for Decision Excellence Model (GUIDE-M) is comprised of 3 core tactics, 7 domains, 9 subdomains, 44 attributes, and 40 subattributes and elements. Feedback on the beta version was received from 248 stakeholders from 34 countries. The model was rated as logical, relevant, and appropriate. Seven PG tools were selected and compared to the GUIDE-M: very few tools targeted the Contextualization and Deliberations domain. Also, fewer of the tools addressed PG appraisal than PG development and reporting functions. These findings informed the research priorities identified by the team. The GUIDE-M provides an evidence-informed international and multidisciplinary conceptualization of PG implementability. The model can be used by PG developers to help them create more implementable recommendations, by clinicians and other users to help them be better consumers of PGs, and by the research community to identify priorities for further investigation.
Piao, Shilong; Sitch, Stephen; Ciais, Philippe; Friedlingstein, Pierre; Peylin, Philippe; Wang, Xuhui; Ahlström, Anders; Anav, Alessandro; Canadell, Josep G; Cong, Nan; Huntingford, Chris; Jung, Martin; Levis, Sam; Levy, Peter E; Li, Junsheng; Lin, Xin; Lomas, Mark R; Lu, Meng; Luo, Yiqi; Ma, Yuecun; Myneni, Ranga B; Poulter, Ben; Sun, Zhenzhong; Wang, Tao; Viovy, Nicolas; Zaehle, Soenke; Zeng, Ning
2013-07-01
The purpose of this study was to evaluate 10 process-based terrestrial biosphere models that were used for the IPCC fifth Assessment Report. The simulated gross primary productivity (GPP) is compared with flux-tower-based estimates by Jung et al. [Journal of Geophysical Research 116 (2011) G00J07] (JU11). The net primary productivity (NPP) apparent sensitivity to climate variability and atmospheric CO2 trends is diagnosed from each model output, using statistical functions. The temperature sensitivity is compared against ecosystem field warming experiments results. The CO2 sensitivity of NPP is compared to the results from four Free-Air CO2 Enrichment (FACE) experiments. The simulated global net biome productivity (NBP) is compared with the residual land sink (RLS) of the global carbon budget from Friedlingstein et al. [Nature Geoscience 3 (2010) 811] (FR10). We found that models produce a higher GPP (133 ± 15 Pg C yr(-1) ) than JU11 (118 ± 6 Pg C yr(-1) ). In response to rising atmospheric CO2 concentration, modeled NPP increases on average by 16% (5-20%) per 100 ppm, a slightly larger apparent sensitivity of NPP to CO2 than that measured at the FACE experiment locations (13% per 100 ppm). Global NBP differs markedly among individual models, although the mean value of 2.0 ± 0.8 Pg C yr(-1) is remarkably close to the mean value of RLS (2.1 ± 1.2 Pg C yr(-1) ). The interannual variability in modeled NBP is significantly correlated with that of RLS for the period 1980-2009. Both model-to-model and interannual variation in model GPP is larger than that in model NBP due to the strong coupling causing a positive correlation between ecosystem respiration and GPP in the model. The average linear regression slope of global NBP vs. temperature across the 10 models is -3.0 ± 1.5 Pg C yr(-1) °C(-1) , within the uncertainty of what derived from RLS (-3.9 ± 1.1 Pg C yr(-1) °C(-1) ). However, 9 of 10 models overestimate the regression slope of NBP vs. precipitation, compared with the slope of the observed RLS vs. precipitation. With most models lacking processes that control GPP and NBP in addition to CO2 and climate, the agreement between modeled and observation-based GPP and NBP can be fortuitous. Carbon-nitrogen interactions (only separable in one model) significantly influence the simulated response of carbon cycle to temperature and atmospheric CO2 concentration, suggesting that nutrients limitations should be included in the next generation of terrestrial biosphere models. © 2013 Blackwell Publishing Ltd.
NASA Astrophysics Data System (ADS)
Ambrose, Jesse L.
2017-12-01
Atmospheric Hg measurements are commonly carried out using Tekran® Instruments Corporation's model 2537 Hg vapor analyzers, which employ gold amalgamation preconcentration sampling and detection by thermal desorption (TD) and atomic fluorescence spectrometry (AFS). A generally overlooked and poorly characterized source of analytical uncertainty in those measurements is the method by which the raw Hg atomic fluorescence (AF) signal is processed. Here I describe new software-based methods for processing the raw signal from the Tekran® 2537 instruments, and I evaluate the performances of those methods together with the standard Tekran® internal signal processing method. For test datasets from two Tekran® instruments (one 2537A and one 2537B), I estimate that signal processing uncertainties in Hg loadings determined with the Tekran® method are within ±[1 % + 1.2 pg] and ±[6 % + 0.21 pg], respectively. I demonstrate that the Tekran® method can produce significant low biases (≥ 5 %) not only at low Hg sample loadings (< 5 pg) but also at tropospheric background concentrations of gaseous elemental mercury (GEM) and total mercury (THg) (˜ 1 to 2 ng m-3) under typical operating conditions (sample loadings of 5-10 pg). Signal processing uncertainties associated with the Tekran® method can therefore represent a significant unaccounted for addition to the overall ˜ 10 to 15 % uncertainty previously estimated for Tekran®-based GEM and THg measurements. Signal processing bias can also add significantly to uncertainties in Tekran®-based gaseous oxidized mercury (GOM) and particle-bound mercury (PBM) measurements, which often derive from Hg sample loadings < 5 pg. In comparison, estimated signal processing uncertainties associated with the new methods described herein are low, ranging from within ±0.053 pg, when the Hg thermal desorption peaks are defined manually, to within ±[2 % + 0.080 pg] when peak definition is automated. Mercury limits of detection (LODs) decrease by 31 to 88 % when the new methods are used in place of the Tekran® method. I recommend that signal processing uncertainties be quantified in future applications of the Tekran® 2537 instruments.
Fabrication and Vibration Results of 30-cm Pyrolytic Graphite Ion Optics
NASA Technical Reports Server (NTRS)
DePano, Michael K.; Hart, Stephen L.; Hanna, Andrew A.; Schneider, Analyn C.
2004-01-01
Boeing Electron Dynamic Devices, Inc. is currently developing pyrolytic graphite (PG) grids designed to operate on 30-cm NSTAR-type thrusters for the Carbon Based Ion Optics (CBIO) program. The PG technology effort of the CBIO program aims to research PG as a flightworthy material for use in dished ion optics by designing, fabricating, and performance testing 30-cm PG grids. As such, PG grid fabrication results will be discussed as will PG design considerations and how they must differ from the NSTAR molybdenum grid design. Surface characteristics and surface processing of PG will be explored relative to effects on voltage breakdown. Part of the CBIO program objectives is to understand the erosion of PG due to Xenon ion bombardment. Discussion of PG and CC sputter yields will be presented relative to molybdenum. These sputter yields will be utilized in the life modeling of carbon-based grids. Finally, vibration results of 30-cm PG grids will be presented and compared to a first-order model generated at Boeing EDD. Performance testing results of the PG grids will not be discussed in this paper as it has yet to be completed.
Mechanistic insights into porous graphene membranes for helium separation and hydrogen purification
NASA Astrophysics Data System (ADS)
Wei, Shuxian; Zhou, Sainan; Wu, Zhonghua; Wang, Maohuai; Wang, Zhaojie; Guo, Wenyue; Lu, Xiaoqing
2018-05-01
Porous graphene (PG) and nitrogen-substituted PG monolayers of 3N-PG and 6N-PG were designed as effective membranes for the separation of He and H2 over Ne, Ar, N2, CO, and CH4 by using density functional theory. Results showed that PG and 3N-PG exhibited suitable pore sizes and relatively high stabilities for He and H2 separation. PG and 3N-PG membranes also presented excellent He and H2 selectivities over Ne, Ar, N2, CO and CH4 at a wide temperature range. 6N-PG membrane exerted unexceptionable permeances of the studied gases, especially He and H2, which could remarkably improve the separation efficiency of He and H2. Analyses on the most stable adsorption configurations and maximum adsorption energies indicated weak Van der Waals interactions between the gases and the three PG-based membranes. Microscopic permeation process analyses based on the minimum energy pathway, energy profiles, and electron density isosurfaces elucidated the remarkable selectivities of He over Ne/CO/N2/Ar/CH4 and H2 over CO/N2/CH4 and the high permeances of He and H2 passing through the three PG-based membranes. This work not only highlighted the potential use of the three PG-based membranes for He separation and H2 purification but also provided a superior alternative strategy to design and screen membrane materials for gas separation.
He, Fupo; Qian, Guowen; Ren, Weiwei; Li, Jiyan; Fan, Peirong; Shi, Haishan; Shi, Xuetao; Deng, Xin; Wu, Shanghua; Ye, Jiandong
2017-04-24
Polymer sphere-based scaffolds, which are prepared by bonding the adjacent spheres via sintering the randomly packed spheres, feature uniform pore structure, full three-dimensional (3D) interconnection, and considerable mechanical strength. However, bioceramic sphere-based scaffolds fabricated by this method have never been reported. Due to high melting temperature of bioceramic, only limited diffusion rate can be achieved when sintering the bioceramic spheres, which is far from enough to form robust bonding between spheres. In the present study, for the first time we fabricated 3D interconnected β-tricalcium phosphate ceramic sphere-based (PG/TCP) scaffolds by introducing phosphate-based glass (PG) as sintering additive and placing uniaxial pressure during the sintering process. The sintering mechanism of PG/TCP scaffolds was unveiled. The PG/TCP scaffolds had hierarchical pore structure, which was composed by interconnected macropores (>200 μm) among spheres, pores (20–120 μm) in the interior of spheres, and micropores (1–3 μm) among the grains. During the sintering process, partial PG reacted with β-TCP, forming β-Ca2P2O7; metal ions from PG substituted to Ca2+ sites of β-TCP. The mechanical properties (compressive strength 2.8–10.6 MPa; compressive modulus 190–620 MPa) and porosity (30%–50%) of scaffolds could be tailored by manipulating the sintering temperatures. The introduction of PG accelerated in vitro degradation of scaffolds, and the PG/TCP scaffolds showed good cytocompatibility. This work may offer a new strategy to prepare bioceramic scaffolds with satisfactory physicochemical properties for application in bone regeneration.
A global carbon assimilation system based on a dual optimization method
NASA Astrophysics Data System (ADS)
Zheng, H.; Li, Y.; Chen, J. M.; Wang, T.; Huang, Q.; Huang, W. X.; Li, S. M.; Yuan, W. P.; Zheng, X.; Zhang, S. P.; Chen, Z. Q.; Jiang, F.
2014-10-01
Ecological models are effective tools to simulate the distribution of global carbon sources and sinks. However, these models often suffer from substantial biases due to inaccurate simulations of complex ecological processes. We introduce a set of scaling factors (parameters) to an ecological model on the basis of plant functional type (PFT) and latitudes. A global carbon assimilation system (GCAS-DOM) is developed by employing a Dual Optimization Method (DOM) to invert the time-dependent ecological model parameter state and the net carbon flux state simultaneously. We use GCAS-DOM to estimate the global distribution of the CO2 flux on 1° ×1° grid cells for the period from 2000 to 2007. Results show that land and ocean absorb -3.69 ± 0.49 Pg C year-1 and -1.91 ± 0.16 Pg C year-1, respectively. North America, Europe and China contribut -0.96 ± 0.15 Pg C year-1, -0.42 ± 0.08 Pg C year-1 and -0.21 ± 0.28 Pg C year-1, respectively. The uncertainties in the flux after optimization by GCAS-DOM have been remarkably reduced by more than 60%. Through parameter optimization, GCAS-DOM can provide improved estimates of the carbon flux for each PFT. Coniferous forest (-0.97 ± 0.27 Pg C year-1) is the largest contributor to the global carbon sink. Fluxes of once-dominant deciduous forest generated by BEPS is reduced to -0.79 ± 0.22 Pg C year-1, being the third largest carbon sink.
Simplified Model for Prediction of Nitrogen Behavior in Land Treatment of Wastewater,
1980-04-01
exchange process was assumed to be instantaneous, soil solution (pg/cm3) whet eas nitrification and denitrification processes Y o=lcolution ofgN0 3) were...of the first-order kinetic type (Selim et al. 1976 Y = concentration of NO3 -N in and Selim and Iskandar 1978). A distribution coeffi- soil solution (pg...ammonium and ni- are needed in order to maintain the continuity of trate in the soil solution . Therefore the rate of N up- NH 4 -N and N0 3-N
Liu, Dan; Cai, Wenwen; Xia, Jiangzhou; Dong, Wenjie; Zhou, Guangsheng; Chen, Yang; Zhang, Haicheng; Yuan, Wenping
2014-01-01
Gross Primary Production (GPP) is the largest flux in the global carbon cycle. However, large uncertainties in current global estimations persist. In this study, we examined the performance of a process-based model (Integrated BIosphere Simulator, IBIS) at 62 eddy covariance sites around the world. Our results indicated that the IBIS model explained 60% of the observed variation in daily GPP at all validation sites. Comparison with a satellite-based vegetation model (Eddy Covariance-Light Use Efficiency, EC-LUE) revealed that the IBIS simulations yielded comparable GPP results as the EC-LUE model. Global mean GPP estimated by the IBIS model was 107.50±1.37 Pg C year(-1) (mean value ± standard deviation) across the vegetated area for the period 2000-2006, consistent with the results of the EC-LUE model (109.39±1.48 Pg C year(-1)). To evaluate the uncertainty introduced by the parameter Vcmax, which represents the maximum photosynthetic capacity, we inversed Vcmax using Markov Chain-Monte Carlo (MCMC) procedures. Using the inversed Vcmax values, the simulated global GPP increased by 16.5 Pg C year(-1), indicating that IBIS model is sensitive to Vcmax, and large uncertainty exists in model parameterization.
Wang, Kefeng; Peng, Changhui; Zhu, Qiuan; ...
2017-09-28
Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195more » Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated. We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC) and mineral-associated organic carbon (MOC). Furthermore, our work represents the first step towards a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.« less
NASA Astrophysics Data System (ADS)
Wang, Kefeng; Peng, Changhui; Zhu, Qiuan; Zhou, Xiaolu; Wang, Meng; Zhang, Kerou; Wang, Gangsheng
2017-10-01
Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195 Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated by Xu et al. (2014). We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC), and mineral-associated organic carbon (MOC). However, our work represents the first step toward a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Kefeng; Peng, Changhui; Zhu, Qiuan
Microbial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process-based model TRIPLEX-GHG was developed by coupling it with the new MEND (Microbial-ENzyme-mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX-MICROBE) shows considerable improvement over the previous version (TRIPLEX-GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195more » Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well-regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated. We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC) and mineral-associated organic carbon (MOC). Furthermore, our work represents the first step towards a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.« less
McArt, J A A; Nydam, D V; Oetzel, G R; Guard, C L
2014-11-01
The purpose was to develop stochastic economic models which address variation in disease risks and costs in order to evaluate different simulated on-farm testing and propylene glycol (PG) treatment strategies based on herd hyperketonemia (HYK) incidence during the first 30 DIM. Data used in model development concerning the difference in health and production consequences between HYK and non-ketotic cows were based on results from 10 studies representing over 13,000 cows from 833 dairy farms in North America, Canada, and Europe. Inputs for PG associated variables were based on a large field trial using cows from 4 free-stall dairy herds (2 in New York and 2 in Wisconsin). Four simulated on-farm testing and treatment strategies were analyzed at herd HYK incidences ranging from 5% to 80% and included: 1) treating all cows with 5d of PG starting at 5 DIM, 2) testing all cows for HYK 1 day per week (e.g. Mondays) from 3 to 16 DIM and treating all positive cows with 5d of oral PG, 3) testing all cows for HYK 2 days per week (e.g. Mondays and Thursdays) from 3 to 9 DIM and treating all positive cows with 5d of oral PG, and 4) testing all cows for HYK 3 days per week (e.g. Mondays, Wednesdays, and Fridays) from 3 to 16 DIM and treating all positive cows with 5d of oral PG. Cost-benefit analysis included the costs associated with labor to test cows, β-hydroxybutyrate test strips, labor to treat cows, PG, and the associated gain in milk production, decrease in DA and early removal risks of PG treated HYK positive cows compared to non-treated HYK positive cows. Stochastic models were developed to account for variability in the distribution of input variables. Per 100 fresh cows in a herd with an HYK incidence of 40%, the mean economic benefits of the 4 different strategies were $1088, $744, $1166, and $760, respectively. Testing cows 2 days per week from 3 to 9 DIM was the most cost-effective strategy for herds with HYK incidences between 15% and 50%; above 50%, treating all fresh cows with 5d of PG was the most cost-effective strategy. These results show that for herds similar to those used in model, when herd HYK incidences rise above 25%, almost any HYK testing and treatment protocol will be economically beneficial for the farm. Copyright © 2014 Elsevier B.V. All rights reserved.
Tian, Hanqin; Lu, Chaoqun; Yang, Jia; ...
2015-06-05
Soil is the largest organic carbon (C) pool of terrestrial ecosystems, and C loss from soil accounts for a large proportion of land-atmosphere C exchange. Therefore, a small change in soil organic C (SOC) can affect atmospheric carbon dioxide (CO₂) concentration and climate change. In the past decades, a wide variety of studies have been conducted to quantify global SOC stocks and soil C exchange with the atmosphere through site measurements, inventories, and empirical/process-based modeling. However, these estimates are highly uncertain, and identifying major driving forces controlling soil C dynamics remains a key research challenge. This study has compiled century-longmore » (1901–2010) estimates of SOC storage and heterotrophic respiration (Rh) from 10 terrestrial biosphere models (TBMs) in the Multi-scale Synthesis and Terrestrial Model Intercomparison Project and two observation-based data sets. The 10 TBM ensemble shows that global SOC estimate ranges from 425 to 2111 Pg C (1 Pg = 10¹⁵ g) with a median value of 1158 Pg C in 2010. The models estimate a broad range of Rh from 35 to 69 Pg C yr⁻¹ with a median value of 51 Pg C yr⁻¹ during 2001–2010. The largest uncertainty in SOC stocks exists in the 40–65°N latitude whereas the largest cross-model divergence in Rh are in the tropics. The modeled SOC change during 1901–2010 ranges from –70 Pg C to 86 Pg C, but in some models the SOC change has a different sign from the change of total C stock, implying very different contribution of vegetation and soil pools in determining the terrestrial C budget among models. The model ensemble-estimated mean residence time of SOC shows a reduction of 3.4 years over the past century, which accelerate C cycling through the land biosphere. All the models agreed that climate and land use changes decreased SOC stocks, while elevated atmospheric CO₂ and nitrogen deposition over intact ecosystems increased SOC stocks—even though the responses varied significantly among models. Model representations of temperature and moisture sensitivity, nutrient limitation, and land use partially explain the divergent estimates of global SOC stocks and soil C fluxes in this study. In addition, a major source of systematic error in model estimations relates to nonmodeled SOC storage in wetlands and peatlands, as well as to old C storage in deep soil layers.« less
NASA Technical Reports Server (NTRS)
Hirsch, A. I.; Little, W. S.; Houghton, R. A.; Scott, N. A.; White, J. D.
2004-01-01
We developed a process-based model of forest growth, carbon cycling, and land cover dynamics named CARLUC (for CARbon and Land Use Change) to estimate the size of terrestrial carbon pools in terra firme (non-flooded) forests across the Brazilian Legal Amazon and the net flux of carbon resulting from forest disturbance and forest recovery from disturbance. Our goal in building the model was to construct a relatively simple ecosystem model that would respond to soil and climatic heterogeneity that allows us to study of the impact of Amazonian deforestation, selective logging, and accidental fire on the global carbon cycle. This paper focuses on the net flux caused by deforestation and forest re-growth over the period from 1970-1998. We calculate that the net flux to the atmosphere during this period reached a maximum of approx. 0.35 PgC/yr (1PgC = 1 x 10(exp I5) gC) in 1990, with a cumulative release of approx. 7 PgC from 1970- 1998. The net flux is higher than predicted by an earlier study by a total of 1 PgC over the period 1989-1 998 mainly because CARLUC predicts relatively high mature forest carbon storage compared to the datasets used in the earlier study. Incorporating the dynamics of litter and soil carbon pools into the model increases the cumulative net flux by approx. 1 PgC from 1970-1998, while different assumptions about land cover dynamics only caused small changes. The uncertainty of the net flux, calculated with a Monte-Carlo approach, is roughly 35% of the mean value (1 SD).
Jenkins, Lucille; Webb, Theresa; Browne, Nick; Afifi, A A; Kraus, Jess
2005-05-01
The purpose of this study was to determine whether the Motion Picture Association of America's ratings system distinguishes among the 3 primary rating categories (PG, PG-13, and R) with respect to violence based on a study of the 100 top-grossing films of 1994. The Motion Picture Association of America assigns age-based ratings for every film that is released in the United States accompanied by the reasons for the rating. A data abstraction instrument was designed to code each act of violence within the sample of 100 films. A series of Poisson regression models were used to examine the association among rating, seriousness of violence, and primary reason for the rating assignment. The total average number of violent acts within each film by rating category increased from PG (14) to PG-13 (20) to R (32). However, using results from the Poisson models, it is clear that the rating does not predict the frequency of violence in films. For all 3 rating categories, the predicted number of violent acts is almost identical for films with violence as a primary descriptor and films with the highest level of seriousness (R = 62.4 acts, PG-13 = 55.2 acts, and PG = 56.1 acts). The regression analysis shows that the rating does not predict the frequency of violence that occurs in films. Frequency of violence alone is not the most important criterion for the assignment of rating. The content descriptors and average seriousness of films are better measures of the violence than rating assignment.
Membrane-anchored Plakoglobins Have Multiple Mechanisms of Action in Wnt Signaling
Klymkowsky, Michael W.; Williams, Bart O.; Barish, Grant D.; Varmus, Harold E.; Vourgourakis, Yanni E.
1999-01-01
In Wnt signaling, β-catenin and plakoglobin transduce signals to the nucleus through interactions with TCF-type transcription factors. However, when plakoglobin is artificially engineered to restrict it to the cytoplasm by fusion with the transmembrane domain of connexin (cnxPg), it efficiently induces a Wnt-like axis duplication phenotype in Xenopus. In Xenopus embryos, maternal XTCF3 normally represses ventral expression of the dorsalizing gene Siamois. Two models have been proposed to explain the Wnt-like activity of cnxPg: 1) that cnxPg inhibits the machinery involved in the turnover of cytosolic β-catenin, which then accumulates and inhibits maternal XTCF3, and 2) that cnxPg directly acts to inhibit XTCF3 activity. To distinguish between these models, we created a series of N-terminal deletion mutations of cnxPg and examined their ability to induce an ectopic axis in Xenopus, activate a TCF-responsive reporter (OT), stabilize β-catenin, and colocalize with components of the Wnt signaling pathway. cnxPg does not colocalize with the Wnt pathway component Dishevelled, but it does lead to the redistribution of APC and Axin, two proteins involved in the regulation of β-catenin turnover. Expression of cnxPg increases levels of cytosolic β-catenin; however, this effect does not completely explain its signaling activity. Although cnxPg and Wnt-1 stabilize β-catenin to similar extents, cnxPg activates OT to 10- to 20-fold higher levels than Wnt-1. Moreover, although LEF1 and TCF4 synergize with β-catenin and plakoglobin to activate OT, both suppress the signaling activity of cnxPg. In contrast, XTCF3 suppresses the signaling activity of both β-catenin and cnxPg. Both exogenous XLEF1 and XTCF3 are sequestered in the cytoplasm of Xenopus cells by cnxPg. Based on these data, we conclude that, in addition to its effects on β-catenin, cnxPg interacts with other components of the Wnt pathway, perhaps TCFs, and that these interactions contribute to its signaling activity. PMID:10512857
Membrane-anchored plakoglobins have multiple mechanisms of action in Wnt signaling.
Klymkowsky, M W; Williams, B O; Barish, G D; Varmus, H E; Vourgourakis, Y E
1999-10-01
In Wnt signaling, beta-catenin and plakoglobin transduce signals to the nucleus through interactions with TCF-type transcription factors. However, when plakoglobin is artificially engineered to restrict it to the cytoplasm by fusion with the transmembrane domain of connexin (cnxPg), it efficiently induces a Wnt-like axis duplication phenotype in Xenopus. In Xenopus embryos, maternal XTCF3 normally represses ventral expression of the dorsalizing gene Siamois. Two models have been proposed to explain the Wnt-like activity of cnxPg: 1) that cnxPg inhibits the machinery involved in the turnover of cytosolic beta-catenin, which then accumulates and inhibits maternal XTCF3, and 2) that cnxPg directly acts to inhibit XTCF3 activity. To distinguish between these models, we created a series of N-terminal deletion mutations of cnxPg and examined their ability to induce an ectopic axis in Xenopus, activate a TCF-responsive reporter (OT), stabilize beta-catenin, and colocalize with components of the Wnt signaling pathway. cnxPg does not colocalize with the Wnt pathway component Dishevelled, but it does lead to the redistribution of APC and Axin, two proteins involved in the regulation of beta-catenin turnover. Expression of cnxPg increases levels of cytosolic beta-catenin; however, this effect does not completely explain its signaling activity. Although cnxPg and Wnt-1 stabilize beta-catenin to similar extents, cnxPg activates OT to 10- to 20-fold higher levels than Wnt-1. Moreover, although LEF1 and TCF4 synergize with beta-catenin and plakoglobin to activate OT, both suppress the signaling activity of cnxPg. In contrast, XTCF3 suppresses the signaling activity of both beta-catenin and cnxPg. Both exogenous XLEF1 and XTCF3 are sequestered in the cytoplasm of Xenopus cells by cnxPg. Based on these data, we conclude that, in addition to its effects on beta-catenin, cnxPg interacts with other components of the Wnt pathway, perhaps TCFs, and that these interactions contribute to its signaling activity.
A global carbon assimilation system based on a dual optimization method
NASA Astrophysics Data System (ADS)
Zheng, H.; Li, Y.; Chen, J. M.; Wang, T.; Huang, Q.; Huang, W. X.; Wang, L. H.; Li, S. M.; Yuan, W. P.; Zheng, X.; Zhang, S. P.; Chen, Z. Q.; Jiang, F.
2015-02-01
Ecological models are effective tools for simulating the distribution of global carbon sources and sinks. However, these models often suffer from substantial biases due to inaccurate simulations of complex ecological processes. We introduce a set of scaling factors (parameters) to an ecological model on the basis of plant functional type (PFT) and latitudes. A global carbon assimilation system (GCAS-DOM) is developed by employing a dual optimization method (DOM) to invert the time-dependent ecological model parameter state and the net carbon flux state simultaneously. We use GCAS-DOM to estimate the global distribution of the CO2 flux on 1° × 1° grid cells for the period from 2001 to 2007. Results show that land and ocean absorb -3.63 ± 0.50 and -1.82 ± 0.16 Pg C yr-1, respectively. North America, Europe and China contribute -0.98 ± 0.15, -0.42 ± 0.08 and -0.20 ± 0.29 Pg C yr-1, respectively. The uncertainties in the flux after optimization by GCAS-DOM have been remarkably reduced by more than 60%. Through parameter optimization, GCAS-DOM can provide improved estimates of the carbon flux for each PFT. Coniferous forest (-0.97 ± 0.27 Pg C yr-1) is the largest contributor to the global carbon sink. Fluxes of once-dominant deciduous forest generated by the Boreal Ecosystems Productivity Simulator (BEPS) are reduced to -0.78 ± 0.23 Pg C yr-1, the third largest carbon sink.
William L. Headlee; Ronald S. Jr. Zalesny; Deahn M. Donner; Richard B. Hall
2013-01-01
Hybrid poplars have demonstrated high biomass productivity in the North Central USA as short rotation woody crops (SRWCs). However, our ability to quantitatively predict productivity for sites that are not currently in SRWCs is limited. As a result, stakeholders are also limited in their ability to evaluate different areas within the region as potential supply sheds...
Permafrost carbon-climate feedbacks accelerate global warming.
Koven, Charles D; Ringeval, Bruno; Friedlingstein, Pierre; Ciais, Philippe; Cadule, Patricia; Khvorostyanov, Dmitry; Krinner, Gerhard; Tarnocai, Charles
2011-09-06
Permafrost soils contain enormous amounts of organic carbon, which could act as a positive feedback to global climate change due to enhanced respiration rates with warming. We have used a terrestrial ecosystem model that includes permafrost carbon dynamics, inhibition of respiration in frozen soil layers, vertical mixing of soil carbon from surface to permafrost layers, and CH(4) emissions from flooded areas, and which better matches new circumpolar inventories of soil carbon stocks, to explore the potential for carbon-climate feedbacks at high latitudes. Contrary to model results for the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4), when permafrost processes are included, terrestrial ecosystems north of 60°N could shift from being a sink to a source of CO(2) by the end of the 21st century when forced by a Special Report on Emissions Scenarios (SRES) A2 climate change scenario. Between 1860 and 2100, the model response to combined CO(2) fertilization and climate change changes from a sink of 68 Pg to a 27 + -7 Pg sink to 4 + -18 Pg source, depending on the processes and parameter values used. The integrated change in carbon due to climate change shifts from near zero, which is within the range of previous model estimates, to a climate-induced loss of carbon by ecosystems in the range of 25 + -3 to 85 + -16 Pg C, depending on processes included in the model, with a best estimate of a 62 + -7 Pg C loss. Methane emissions from high-latitude regions are calculated to increase from 34 Tg CH(4)/y to 41-70 Tg CH(4)/y, with increases due to CO(2) fertilization, permafrost thaw, and warming-induced increased CH(4) flux densities partially offset by a reduction in wetland extent.
He, Fupo; Ren, Weiwei; Tian, Xiumei; Liu, Wei; Wu, Shanghua; Chen, Xiaoming
2016-07-01
In a previous study, robust calcium carbonate composite ceramics (CC/PG) were prepared by using phosphate-based glass (PG) as an additive, which showed good cell response. In the present study the in vivo response of porous CC/PG was compared to that of porous biphasic calcium phosphate ceramics (BCP), using a rabbit femoral critical-size grafting model. The materials degradation and bone formation processes were evaluated by general observation, X-ray radiography, micro-computed tomography, and histological examination. The results demonstrated excellent biocompatibility and osteoconductivity, and progressive degradation of CC/PG and BCP. Although the in vitro degradation rate of CC/PG was distinctly faster than that of BCP, at 4week post-implantation, the bone generation and material degradation of CC/PG were less than those of BCP. Nevertheless, at postoperative week 8, the increment of bone formation and material degradation of CC/PG was pronouncedly larger than that of BCP. These results show that CC/PG is a potential resorbable bone graft aside from the traditional synthetic ones. Copyright © 2016 Elsevier B.V. All rights reserved.
Development of PBPK Models for Gasoline in Adult and ...
Concern for potential developmental effects of exposure to gasoline-ethanol blends has grown along with their increased use in the US fuel supply. Physiologically-based pharmacokinetic (PBPK) models for these complex mixtures were developed to address dosimetric issues related to selection of exposure concentrations for in vivo toxicity studies. Sub-models for individual hydrocarbon (HC) constituents were first developed and calibrated with published literature or QSAR-derived data where available. Successfully calibrated sub-models for individual HCs were combined, assuming competitive metabolic inhibition in the liver, and a priori simulations of mixture interactions were performed. Blood HC concentration data were collected from exposed adult non-pregnant (NP) rats (9K ppm total HC vapor, 6h/day) to evaluate performance of the NP mixture model. This model was then converted to a pregnant (PG) rat mixture model using gestational growth equations that enabled a priori estimation of life-stage specific kinetic differences. To address the impact of changing relevant physiological parameters from NP to PG, the PG mixture model was first calibrated against the NP data. The PG mixture model was then evaluated against data from PG rats that were subsequently exposed (9K ppm/6.33h gestation days (GD) 9-20). Overall, the mixture models adequately simulated concentrations of HCs in blood from single (NP) or repeated (PG) exposures (within ~2-3 fold of measured values of
NASA Astrophysics Data System (ADS)
Wang, L.; Zhang, F.; Zhang, H.; Scott, C. A.; Zeng, C.; SHI, X.
2017-12-01
Precipitation is one of the crucial inputs for models used to better understand hydrological processes. In high mountain areas, it is a difficult task to obtain a reliable precipitation data set describing the spatial and temporal characteristic due to the limited meteorological observations and high variability of precipitation. This study carries out intensive observation of precipitation in a high mountain catchment in the southeast of the Tibet during July to August 2013. According to the rain gauges set up at different altitudes, it is found that precipitation is greatly influenced by altitude. The observed precipitation is used to depict the precipitation gradient (PG) and hourly distribution (HD), showing that the average duration is around 0.1, 0.8 and 6.0 hours and the average PG is 0.10, 0.28 and 0.26 mm/d/100m for trace, light and moderate rain, respectively. Based on the gridded precipitation derived from the PG and HD and the nearby Linzhi meteorological station at lower altitude, a distributed biosphere hydrological model based on water and energy budgets (WEB-DHM) is applied to simulate the hydrological processes. Beside the observed runoff, MODIS/Terra snow cover area (SCA) data, and MODIS/Terra land surface temperature (LST) data are also used for model calibration and validation. The resulting runoff, SCA and LST simulations are all reasonable. Sensitivity analyses indicate that runoff is greatly underestimated without considering PG, illustrating that short-term intensive precipitation observation contributes to improving hydrological modelling of poorly gauged high mountain catchments.
NASA Astrophysics Data System (ADS)
Zscheischler, Jakob; Mahecha, Miguel D.; Avitabile, Valerio; Calle, Leonardo; Carvalhais, Nuno; Ciais, Philippe; Gans, Fabian; Gruber, Nicolas; Hartmann, Jens; Herold, Martin; Ichii, Kazuhito; Jung, Martin; Landschützer, Peter; Laruelle, Goulven G.; Lauerwald, Ronny; Papale, Dario; Peylin, Philippe; Poulter, Benjamin; Ray, Deepak; Regnier, Pierre; Rödenbeck, Christian; Roman-Cuesta, Rosa M.; Schwalm, Christopher; Tramontana, Gianluca; Tyukavina, Alexandra; Valentini, Riccardo; van der Werf, Guido; West, Tristram O.; Wolf, Julie E.; Reichstein, Markus
2017-08-01
Understanding the global carbon (C) cycle is of crucial importance to map current and future climate dynamics relative to global environmental change. A full characterization of C cycling requires detailed information on spatiotemporal patterns of surface-atmosphere fluxes. However, relevant C cycle observations are highly variable in their coverage and reporting standards. Especially problematic is the lack of integration of the carbon dioxide (CO2) exchange of the ocean, inland freshwaters and the land surface with the atmosphere. Here we adopt a data-driven approach to synthesize a wide range of observation-based spatially explicit surface-atmosphere CO2 fluxes from 2001 to 2010, to identify the state of today's observational opportunities and data limitations. The considered fluxes include net exchange of open oceans, continental shelves, estuaries, rivers, and lakes, as well as CO2 fluxes related to net ecosystem productivity, fire emissions, loss of tropical aboveground C, harvested wood and crops, as well as fossil fuel and cement emissions. Spatially explicit CO2 fluxes are obtained through geostatistical and/or remote-sensing-based upscaling, thereby minimizing biophysical or biogeochemical assumptions encoded in process-based models. We estimate a bottom-up net C exchange (NCE) between the surface (land, ocean, and coastal areas) and the atmosphere. Though we provide also global estimates, the primary goal of this study is to identify key uncertainties and observational shortcomings that need to be prioritized in the expansion of in situ observatories. Uncertainties for NCE and its components are derived using resampling. In many regions, our NCE estimates agree well with independent estimates from other sources such as process-based models and atmospheric inversions. This holds for Europe (mean ± 1 SD: 0.8 ± 0.1 PgC yr-1, positive numbers are sources to the atmosphere), Russia (0.1 ± 0.4 PgC yr-1), East Asia (1.6 ± 0.3 PgC yr-1), South Asia (0.3 ± 0.1 PgC yr-1), Australia (0.2 ± 0.3 PgC yr-1), and most of the Ocean regions. Our NCE estimates give a likely too large CO2 sink in tropical areas such as the Amazon, Congo, and Indonesia. Overall, and because of the overestimated CO2 uptake in tropical lands, our global bottom-up NCE amounts to a net sink of -5.4 ± 2.0 PgC yr-1. By contrast, the accurately measured mean atmospheric growth rate of CO2 over 2001-2010 indicates that the true value of NCE is a net CO2 source of 4.3 ± 0.1 PgC yr-1. This mismatch of nearly 10 PgC yr-1 highlights observational gaps and limitations of data-driven models in tropical lands, but also in North America. Our uncertainty assessment provides the basis for setting priority regions where to increase carbon observations in the future. High on the priority list are tropical land regions, which suffer from a lack of in situ observations. Second, extensive pCO2 data are missing in the Southern Ocean. Third, we lack observations that could enable seasonal estimates of shelf, estuary, and inland water-atmosphere C exchange. Our consistent derivation of data uncertainties could serve as prior knowledge in multicriteria optimization such as the Carbon Cycle Data Assimilation System (CCDAS) and atmospheric inversions, without over- or under-stating bottom-up data credibility. In the future, NCE estimates of carbon sinks could be aggregated at national scale to compare with the official national inventories of CO2 fluxes in the land use, land use change, and forestry sector, upon which future emission reductions are proposed.
Xiu, Hao; Nuruzzaman, Mohammed; Guo, Xiangqian; Cao, Hongzhe; Huang, Jingjia; Chen, Xianghui; Wu, Kunlu; Zhang, Ru; Huang, Yuzhao; Luo, Junli; Luo, Zhiyong
2016-03-04
Despite the importance of WRKY genes in plant physiological processes, little is known about their roles in Panax ginseng C.A. Meyer. Forty-eight unigenes on this species were previously reported as WRKY transcripts using the next-generation sequencing (NGS) technology. Subsequently, one gene that encodes PgWRKY1 protein belonging to subgroup II-d was cloned and functionally characterized. In this study, eight WRKY genes from the NGS-based transcriptome sequencing dataset designated as PgWRKY2-9 have been cloned and characterized. The genes encoding WRKY proteins were assigned to WRKY Group II (one subgroup II-c, four subgroup II-d, and three subgroup II-e) based on phylogenetic analysis. The cDNAs of the cloned PgWRKYs encode putative proteins ranging from 194 to 358 amino acid residues, each of which includes one WRKYGQK sequence motif and one C₂H₂-type zinc-finger motif. Quantitative real-time PCR (qRT-PCR) analysis demonstrated that the eight analyzed PgWRKY genes were expressed at different levels in various organs including leaves, roots, adventitious roots, stems, and seeds. Importantly, the transcription responses of these PgWRKYs to methyl jasmonate (MeJA) showed that PgWRKY2, PgWRKY3, PgWRKY4, PgWRKY5, PgWRKY6, and PgWRKY7 were downregulated by MeJA treatment, while PgWRKY8 and PgWRKY9 were upregulated to varying degrees. Moreover, the PgWRKY genes increased or decreased by salicylic acid (SA), abscisic acid (ABA), and NaCl treatments. The results suggest that the PgWRKYs may be multiple stress-inducible genes responding to both salt and hormones.
McIntosh, C C; Crino, R D; O'Neill, K
2016-12-01
The problem gambling (PG) intervention literature is characterised by a variety of psychological treatments and approaches, with varying levels of evidence (PGRTC in Guideline for screening, assessment and treatment in problem and pathological gambling. Monash University, Melbourne, 2011). A recent PG systematic review (Maynard et al. in Res Soc Work Pract, 2015. doi: 10.1177/1049731515606977 ) and the success of mindfulness-based interventions to effectively treat disorders commonly comorbid with PG suggested mindfulness-based interventions may be effective for treating PG. The current study tested the effectiveness of three interventions to treat PGs: 1. case formulation driven Cognitive Behaviour Therapy (CBT); 2. manualised CBT; and 3. mindfulness-based treatment. All three interventions tested returned large effect size improvements in PG behaviour after seven sessions (Cohen's d range 1.46-2.01), at post-treatment and at 3 and 6-month follow-up. All of the interventions were rated as acceptable by participants at post-treatment. This study suggests that the mindfulness-based and TAU interventions used in the current study appear to be effective at reducing PG behavior and associated distress and they also appear to generalise to improvements in other measures such as quality of life-mental functioning and certain mindfulness facets more effectively than the manualised form of CBT utilised used here. Secondly, a brief mindfulness intervention delivered after psycho-education and a brief CBT intervention may be a useful supplement to traditional CBT treatments by addressing transdiagnostic processes such as rumination and thought suppression. Thirdly, CBT interventions continue to report effectiveness in reducing PG behaviour and associated distress consistent with the prevailing literature and clinical direction.
Zhang, Mei; Zhu, Lin; Cui, Steve W; Wang, Qi; Zhou, Ting; Shen, Hengsheng
2011-01-01
Fractionation and purification of mushroom polysaccharides is a critical process for mushroom clinical application. After a hot-water treatment, the crude Pleurotus geesteranus (PG) was further fractionated into four fractions (PG-1, -2, -3, -4) using gradient precipitation with water and ammonia sulphate. By controlling the initial polymer concentration and ratio of solvents, this process produced PG fractions with high chemical uniformity and narrow Mw distribution without free proteins. Structurally, PG-1 and PG-2 are pure homopolysaccharide mainly composed of glucose; and PG-3 and PG-4 are heteropolysaccharide-protein complexes. PG-2, a high M(w) fraction mainly composed of glucose presented significant cytotoxicity at the concentration of 200 and 100 μg/ml to human breast cancer cells. Here, we report a new mushroom polysaccharides extraction and fractionation method, with which we produced four fractions of PG with PG-2 appearing effective anti-tumour activity. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.
The PG-TRAK Manual: Using PGCC's Custom Lifestyle Cluster System. Market Analysis MA91-3.
ERIC Educational Resources Information Center
Boughan, Karl
In early 1990, Prince George's Community College (PGCC), in response to declining enrollments, developed an affordable and locally effective geo-demographic cluster system for meeting the college's research and marketing needs. The system, dubbed "PG-TRAK," is based on a model developed 15 years ago as a corporate marketing tool, and involves…
Survey of polyfluorinated chemicals (PFCs) in the atmosphere over the northeast Atlantic Ocean
NASA Astrophysics Data System (ADS)
Shoeib, Mahiba; Vlahos, Penny; Harner, Tom; Peters, Andrew; Graustein, Margaret; Narayan, Julie
2010-08-01
High volume air sampling in Bermuda, Sable Island (Nova Scotia) and along a cruise track from the Gulf of Mexico to northeast coast of the USA, was carried out to assess air concentrations, particle-gas partitioning and transport of polyfluorinated chemicals (PFCs) in this region. Samples were collected in the summer of 2007. Targeted compounds included the neutral PFCs: fluorotelomer alcohols (FTOHs), perfluoroalkyl sulfonamides (FOSAs) and perfluoroalkyl sulfonamido ethanols (FOSEs). Among the FTOHs, 8:2 FTOH was dominant in all samples. Sum of the concentration of FTOHs (gas+particle phase) were higher in Bermuda (mean, 34 pg m -3) compared to Sable Island (mean, 16 pg m -3). In cruise samples, sum of FTOHs were highly variable (mean, 81 pg m -3) reflecting contributions from land-based sources in the northeast USA with concentrations reaching as high as 156 pg m -3. Among the FOSAs and FOSEs, MeFOSE was dominant in all samples. In Bermuda, levels of MeFOSE were exceptionally high (mean, 62 pg m -3), exceeding the FTOHs. Sable Island samples also exhibited the dominance of MeFOSE but at a lower concentration (mean, 15 pg m -3). MeFOSE air concentrations (pg m -3) in cruise samples ranged from 1.6 to 73 and were not linked to land-based sources. In fact high concentrations of MeFOSE observed in Bermuda were associated with air masses that originated over the Atlantic Ocean. The partitioning to particles for 8:2 FTOH, 10:2 FTOH, MeFOSE and EtFOSE ranged from as high as 15 to 42% for cruise samples to 0.9 to 14% in Bermuda. This study provides key information for validating and developing partitioning and transport models for the PFCs.
William Lazarus; William L. Headlee; Ronald S. Zalesny
2015-01-01
The joint effects of poplar biomass productivity and land costs on poplar production economics were compared for 12 Minnesota counties and two genetic groups, using a process-based model (3-PG) to estimate productivity. The counties represent three levels of productivity and a range of land costs (annual rental rates) from $128/ha to $534/ha. An optimal rotation age...
The impacts of recent permafrost thaw on land-atmosphere greenhouse gas exchange
Hayes, Daniel J.; Kicklighter, David W.; McGuire, A. David; Chen, Min; Zhuang, Qianlai; Yuan, Fengming; Melillo, Jerry M.; Wullschleger, Stan D.
2014-01-01
Permafrost thaw and the subsequent mobilization of carbon (C) stored in previously frozen soil organic matter (SOM) have the potential to be a strong positive feedback to climate. As the northern permafrost region experiences as much as a doubling of the rate of warming as the rest of the Earth, the vast amount of C in permafrost soils is vulnerable to thaw, decomposition and release as atmospheric greenhouse gases. Diagnostic and predictive estimates of high-latitude terrestrial C fluxes vary widely among different models depending on how dynamics in permafrost, and the seasonally thawed 'active layer' above it, are represented. Here, we employ a process-based model simulation experiment to assess the net effect of active layer dynamics on this 'permafrost carbon feedback' in recent decades, from 1970 to 2006, over the circumpolar domain of continuous and discontinuous permafrost. Over this time period, the model estimates a mean increase of 6.8 cm in active layer thickness across the domain, which exposes a total of 11.6 Pg C of thawed SOM to decomposition. According to our simulation experiment, mobilization of this previously frozen C results in an estimated cumulative net source of 3.7 Pg C to the atmosphere since 1970 directly tied to active layer dynamics. Enhanced decomposition from the newly exposed SOM accounts for the release of both CO2 (4.0 Pg C) and CH4 (0.03 Pg C), but is partially compensated by CO2 uptake (0.3 Pg C) associated with enhanced net primary production of vegetation. This estimated net C transfer to the atmosphere from permafrost thaw represents a significant factor in the overall ecosystem carbon budget of the Pan-Arctic, and a non-trivial additional contribution on top of the combined fossil fuel emissions from the eight Arctic nations over this time period.
Arivizhivendhan, K V; Mahesh, M; Boopathy, R; Patchaimurugan, K; Maharaja, P; Swarnalatha, S; Regina Mary, R; Sekaran, G
2016-09-15
Prodigiosin (PG) is a bioactive compound produced by several bacterial species. Currently, many technologies are being developed for the production of PG by fermentation processes. However, new challenges are being faced with regard to the production of PG in terms of the recovery and purification steps, owing to the labile nature of PG molecules and the cost of the purification steps. Conventional methods have limitations due to high cost, low reusability, and health hazards. Hence, the present investigation was focused on the development of surface-functionalized magnetic iron oxide ([Fe3O4]F) for solvent-free extraction of bioactive PG from the bacterial fermented medium. Fe3O4 was functionalized with diethanolamine and characterized by FT-IR, diffuse reflectance spectroscopy, thermogravimetric analysis, scanning electron microscopy, and confocal microscopy. The various process parameters, such as contact time, temperature, pH, and mass of Fe3O4, were optimized for the extraction of PG using functionalized Fe3O4. Instrumental analyses confirmed that the PG molecules were cross-linked with functional groups on [Fe3O4]F through van der Waals forces of attraction. PG extracted through Fe3O4 or [Fe3O4]F was separated from the fermentation medium by applying an external electromagnetic field and regenerated for successive reuse cycles. The purity of the extracted PG was characterized by high-performance liquid chromatography, FT-IR, and UV-visible spectroscopy. The iron oxide-diethanolamine-PG cross-linked ([Fe3O4]F-PG) composite matrix effectively deactivates harmful fouling by cyanobacterial growth in water-treatment plants. The present investigation provides the possibility of solvent-free extraction of bacterial bioactive PG from a fermented medium using functionalized magnetic iron oxide.
NASA Astrophysics Data System (ADS)
Wang, Li; Zhang, Fan; Zhang, Hongbo; Scott, Christopher A.; Zeng, Chen; Shi, Xiaonan
2018-01-01
Precipitation is one of the most critical inputs for models used to improve understanding of hydrological processes. In high mountain areas, it is challenging to generate a reliable precipitation data set capturing the spatial and temporal heterogeneity due to the harsh climate, extreme terrain and the lack of observations. This study conducts intensive observation of precipitation in the Mabengnong catchment in the southeast of the Tibetan Plateau during July to August 2013. Because precipitation is greatly influenced by altitude, the observed data are used to characterize the precipitation gradient (PG) and hourly distribution (HD), showing that the average PG is 0.10, 0.28 and 0.26 mm/d/100 m and the average duration is around 0.1, 0.8 and 5.2 h for trace, light and moderate rain, respectively. A distributed biosphere hydrological model based on water and energy budgets with improved physical process for snow (WEB-DHM-S) is applied to simulate the hydrological processes with gridded precipitation data derived from a lower altitude meteorological station and the PG and HD characterized for the study area. The observed runoff, MODIS/Terra snow cover area (SCA) data, and MODIS/Terra land surface temperature (LST) data are used for model calibration and validation. Runoff, SCA and LST simulations all show reasonable results. Sensitivity analyses illustrate that runoff is largely underestimated without considering PG, indicating that short-term intensive precipitation observation has the potential to greatly improve hydrological modelling of poorly gauged high mountain catchments.
Neutral poly- and perfluoroalkyl substances in air and seawater of the North Sea.
Xie, Zhiyong; Zhao, Zhen; Möller, Axel; Wolschke, Hendrik; Ahrens, Lutz; Sturm, Renate; Ebinghaus, Ralf
2013-11-01
Concentrations of neutral poly- and perfluoroalkyl substances (PFASs), such as fluorotelomer alcohols (FTOHs), perfluoroalkane sulfonamides (FASAs), perfluoroalkane sufonamidoethanols (FASEs), and fluorotelomer acrylates (FTACs), have been simultaneously determined in surface seawater and the atmosphere of the North Sea. Seawater and air samples were taken aboard the German research vessel Heincke on the cruise 303 from 15 to 24 May 2009. The concentrations of FTOHs, FASAs, FASEs, and FTACs in the dissolved phase were 2.6-74, <0.1-19, <0.1-63, and <1.0-9.0 pg L(-1), respectively. The highest concentrations were determined in the estuary of the Weser and Elbe rivers and a decreasing concentration profile appeared with increasing distance from the coast toward the central part of the North Sea. Gaseous FTOHs, FASAs, FASEs, and FTACs were in the range of 36-126, 3.1-26, 3.7-19, and 0.8-5.6 pg m(-3), which were consistent with the concentrations determined in 2007 in the North Sea, and approximately five times lower than those reported for an urban area of Northern Germany. These results suggested continuous continental emissions of neutral PFASs followed by transport toward the marine environment. Air-seawater gas exchanges of neutral PFASs were estimated using fugacity ratios and the two-film resistance model based upon paired air-seawater concentrations and estimated Henry's law constant values. Volatilization dominated for all neutral PFASs in the North Sea. The air-seawater gas exchange fluxes were in the range of 2.5×10(3)-3.6×10(5) pg m(-2) for FTOHs, 1.8×10(2)-1.0×10(5) pg m(-2) for FASAs, 1.1×10(2)-3.0×10(5) pg m(-2) for FASEs and 6.3×10(2)-2.0×10(4) pg m(-2) for FTACs, respectively. These results suggest that the air-seawater gas exchange is an important process that intervenes in the transport and fate for neutral PFASs in the marine environment.
Global spatiotemporal distribution of soil respiration modeled using a global database
NASA Astrophysics Data System (ADS)
Hashimoto, S.; Carvalhais, N.; Ito, A.; Migliavacca, M.; Nishina, K.; Reichstein, M.
2015-07-01
The flux of carbon dioxide from the soil to the atmosphere (soil respiration) is one of the major fluxes in the global carbon cycle. At present, the accumulated field observation data cover a wide range of geographical locations and climate conditions. However, there are still large uncertainties in the magnitude and spatiotemporal variation of global soil respiration. Using a global soil respiration data set, we developed a climate-driven model of soil respiration by modifying and updating Raich's model, and the global spatiotemporal distribution of soil respiration was examined using this model. The model was applied at a spatial resolution of 0.5°and a monthly time step. Soil respiration was divided into the heterotrophic and autotrophic components of respiration using an empirical model. The estimated mean annual global soil respiration was 91 Pg C yr-1 (between 1965 and 2012; Monte Carlo 95 % confidence interval: 87-95 Pg C yr-1) and increased at the rate of 0.09 Pg C yr-2. The contribution of soil respiration from boreal regions to the total increase in global soil respiration was on the same order of magnitude as that of tropical and temperate regions, despite a lower absolute magnitude of soil respiration in boreal regions. The estimated annual global heterotrophic respiration and global autotrophic respiration were 51 and 40 Pg C yr-1, respectively. The global soil respiration responded to the increase in air temperature at the rate of 3.3 Pg C yr-1 °C-1, and Q10 = 1.4. Our study scaled up observed soil respiration values from field measurements to estimate global soil respiration and provide a data-oriented estimate of global soil respiration. The estimates are based on a semi-empirical model parameterized with over one thousand data points. Our analysis indicates that the climate controls on soil respiration may translate into an increasing trend in global soil respiration and our analysis emphasizes the relevance of the soil carbon flux from soil to the atmosphere in response to climate change. Further approaches should additionally focus on climate controls in soil respiration in combination with changes in vegetation dynamics and soil carbon stocks, along with their effects on the long temporal dynamics of soil respiration. We expect that these spatiotemporal estimates will provide a benchmark for future studies and also help to constrain process-oriented models.
Permafrost carbon-climate feedbacks accelerate global warming
Koven, Charles D.; Ringeval, Bruno; Friedlingstein, Pierre; Ciais, Philippe; Cadule, Patricia; Khvorostyanov, Dmitry; Krinner, Gerhard; Tarnocai, Charles
2011-01-01
Permafrost soils contain enormous amounts of organic carbon, which could act as a positive feedback to global climate change due to enhanced respiration rates with warming. We have used a terrestrial ecosystem model that includes permafrost carbon dynamics, inhibition of respiration in frozen soil layers, vertical mixing of soil carbon from surface to permafrost layers, and CH4 emissions from flooded areas, and which better matches new circumpolar inventories of soil carbon stocks, to explore the potential for carbon-climate feedbacks at high latitudes. Contrary to model results for the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4), when permafrost processes are included, terrestrial ecosystems north of 60°N could shift from being a sink to a source of CO2 by the end of the 21st century when forced by a Special Report on Emissions Scenarios (SRES) A2 climate change scenario. Between 1860 and 2100, the model response to combined CO2 fertilization and climate change changes from a sink of 68 Pg to a 27 + -7 Pg sink to 4 + -18 Pg source, depending on the processes and parameter values used. The integrated change in carbon due to climate change shifts from near zero, which is within the range of previous model estimates, to a climate-induced loss of carbon by ecosystems in the range of 25 + -3 to 85 + -16 Pg C, depending on processes included in the model, with a best estimate of a 62 + -7 Pg C loss. Methane emissions from high-latitude regions are calculated to increase from 34 Tg CH4/y to 41–70 Tg CH4/y, with increases due to CO2 fertilization, permafrost thaw, and warming-induced increased CH4 flux densities partially offset by a reduction in wetland extent. PMID:21852573
Lawrence, David M.; Koven, Charles; Clein, Joy S.; Burke, Eleanor; Chen, Guangsheng; Jafarov, Elchin; MacDougall, Andrew H.; Marchenko, Sergey; Nicolsky, Dmitry; Peng, Shushi; Rinke, Annette; Ciais, Philippe; Gouttevin, Isabelle; Krinner, Gerhard; Moore, John C.; Romanovsky, Vladimir; Schädel, Christina; Schaefer, Kevin; Zhuang, Qianlai
2018-01-01
We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon–climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2 for the RCP4.5 climate and between 6 and 16 million km2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbon varied between 66-Pg C (1015-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. This assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon–climate feedback. PMID:29581283
McGuire, A. David; Lawrence, David M.; Koven, Charles; ...
2018-03-26
We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon–climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2 for the RCP4.5 climate and between 6 and 16 million km 2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbonmore » varied between 66-Pg C (10 15-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. In conclusion, this assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon–climate feedback.« less
McGuire, A. David; Lawrence, David M.; Koven, Charles; Clein, Joy S.; Burke, Eleanor J.; Chen, Guangsheng; Jafarov, Elchin; MacDougall, Andrew H.; Marchenko, Sergey S.; Nicolsky, Dmitry J.; Peng, Shushi; Rinke, Annette; Ciais, Philippe; Gouttevin, Isabelle; Hayes, Daniel J.; Ji, Duoying; Krinner, Gerhard; Moore, John C.; Romanovsky, Vladimir; Schadel, Christina; Schaefer, Kevin; Schuur, Edward A.G.; Zhuang, Qianlai
2018-01-01
We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon–climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2 for the RCP4.5 climate and between 6 and 16 million km2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbon varied between 66-Pg C (1015-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. This assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon–climate feedback.
McGuire, A David; Lawrence, David M; Koven, Charles; Clein, Joy S; Burke, Eleanor; Chen, Guangsheng; Jafarov, Elchin; MacDougall, Andrew H; Marchenko, Sergey; Nicolsky, Dmitry; Peng, Shushi; Rinke, Annette; Ciais, Philippe; Gouttevin, Isabelle; Hayes, Daniel J; Ji, Duoying; Krinner, Gerhard; Moore, John C; Romanovsky, Vladimir; Schädel, Christina; Schaefer, Kevin; Schuur, Edward A G; Zhuang, Qianlai
2018-04-10
We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon-climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km 2 for the RCP4.5 climate and between 6 and 16 million km 2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbon varied between 66-Pg C (10 15 -g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. This assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon-climate feedback. Copyright © 2018 the Author(s). Published by PNAS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McGuire, A. David; Lawrence, David M.; Koven, Charles
We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon–climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2 for the RCP4.5 climate and between 6 and 16 million km 2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbonmore » varied between 66-Pg C (10 15-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. In conclusion, this assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon–climate feedback.« less
D. A. Sampson; R. H. Waring; C. A. Maier; C. M. Gough; M. J. Ducey; K. H. Johnsen
2006-01-01
A critical ecological question in plantation management is whether fertilization, which generally increases yield, results in enhanced C sequestration over short rotations. We present a rotation-length hybrid process model (SECRETS-3PG) that was calibrated (using control treatments; CW) and verified (using fertilized treatments; FW) using daily estimates of H
D.A. Sampson; R.H. Waring; C.A. Maier; C.M. Gough; M.J. Ducey; K.H. Kohnsen
2006-01-01
A critical ecological question in plantation management is whether fertilization, which generally increases yield, results in enhanced C sequestration over short rotations. We present a rotation-length hybrid process model (SECRETS-3PG) that was calibrated (using control treatments; CW) and verified (using fertilized treatments; FW) using daily estimates of H
NASA Astrophysics Data System (ADS)
Nakayama, Tadanobu
2017-04-01
Recent research showed that inland water including rivers, lakes, and groundwater may play some role in carbon cycling, although its contribution has remained uncertain due to limited amount of reliable data available. In this study, the author developed an advanced model coupling eco-hydrology and biogeochemical cycle (National Integrated Catchment-based Eco-hydrology (NICE)-BGC). This new model incorporates complex coupling of hydrologic-carbon cycle in terrestrial-aquatic linkages and interplay between inorganic and organic carbon during the whole process of carbon cycling. The model could simulate both horizontal transports (export from land to inland water 2.01 ± 1.98 Pg C/yr and transported to ocean 1.13 ± 0.50 Pg C/yr) and vertical fluxes (degassing 0.79 ± 0.38 Pg C/yr, and sediment storage 0.20 ± 0.09 Pg C/yr) in major rivers in good agreement with previous researches, which was an improved estimate of carbon flux from previous studies. The model results also showed global net land flux simulated by NICE-BGC (-1.05 ± 0.62 Pg C/yr) decreased carbon sink a little in comparison with revised Lund-Potsdam-Jena Wetland Hydrology and Methane (-1.79 ± 0.64 Pg C/yr) and previous materials (-2.8 to -1.4 Pg C/yr). This is attributable to CO2 evasion and lateral carbon transport explicitly included in the model, and the result suggests that most previous researches have generally overestimated the accumulation of terrestrial carbon and underestimated the potential for lateral transport. The results further implied difference between inverse techniques and budget estimates suggested can be explained to some extent by a net source from inland water. NICE-BGC would play an important role in reevaluation of greenhouse gas budget of the biosphere, quantification of hot spots, and bridging the gap between top-down and bottom-up approaches to global carbon budget.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morrill, J.S.; Benesch, W.M.
Previous model results have shown that the N{sub 2} triplet vibrational level populations in the aurora are strongly affected by cascade and quenching by atomic and molecular oxygen. As the aurora penetrates to lower altitudes (less than 100 km) the role of quenching by atomic oxygen becomes less important and processes involving N{sub 2} collisions begin to play a more prominent part. The authors are developing a model which will yield steady state vibrational level populations for both the singlet and triplet valence states of N{sub 2}. The model currently provides results for the seven low-lying N{sub 2} triplet statesmore » (A {sup 3}{Sigma}{sub u}{sup +}, B {sup 3}{Pi}{sub g}, W {sup 3}{Delta}{sub u}, B{prime}{sup 3}{Sigma}{sub u}, C{sup 3}{Pi}{sub u}, D{sup 3}{Sigma}{sub u}{sup +}, and E{sup 3}{Sigma}{sub g}{sup +}). These states are responsible for auroral emissions from the UV (Vegard-Kaplan (VK), second positive (2PG)) through the visible to the infrared (first positive (1PG), infrared afterglow (IRA), Wu-Benesch (WB)). The authors have included two additional collisional processes in the current model which were not treated previously. These are the intersystem collisional transfer of excitation (ICT) between the B state and the A, W, and B{prime} states and vibrational redistribution within the A state vibrational manifold, both due to collisions with ground state N{sub 2}. The present work compares the current model results with those of a previous model as well as ground, airborne, and rocket observations. The comparison between N{sub 2}(A) (VK) and N{sub 2}(B) (1PG) vibrational level populations predicted by this model and a number of auroral observations indicate that the current model achieves a significant improvement in the fit between calculation and observation. 81 refs., 12 figs., 2 tabs.« less
Kim, Jihyun; Park, Yuran; Park, Meejung; Kim, Eunmi; Yang, Wonkyung; Baeck, Seungkyung; Lee, Sooyeun; Han, Sangbeom
2015-01-01
The continuing appearance of new synthetic cannabinoids has been a major issue in the field of forensic and clinical toxicology. In response to that, analytical methods for synthetic cannabinoids have been increasingly established in a variety of biological matrices. Since most of synthetic cannabinoids with structure similarity share some enzymatic metabolites, making the interpretation of analytical results and the discovery of the parent drug actually ingested very complicated, the investigation on metabolites of the first generation of synthetic cannabinoids with their relatively short side chains in chemical structure could be more important. Therefore, in the present study, we developed the analytical method for AM-2201, JWH-122 and MAM-2201 with JWH-018 as a precursor and their monohydroxylated metabolites in hair matrix. Also, using a rat model, AM-2201 and its monohydroxylated metabolites were identified and then the ratios of metabolite-to-parent drug were estimated to be used as criteria on external contamination. All analytes were extracted with methanol from washed and cut hair samples and the extracts were injected into LC-MS/MS with electrospray ion source in the positive ionization mode. Matrix effect and recovery were evaluated in hair matrices and no significant variations were observed. The validation results for precision and accuracy were satisfactory in both human and rat hair. The LOD and LOQ were 0.5 pg/10mg and 1.0 pg/10mg in human hair and 0.5 pg/20mg and 1.0 pg/20mg in pigmented and non-pigmented rat hair, respectively. Additionally, as a result of the animal study, there were not significant differences in the effect of pigmentation on the distribution of AM-2201 and its monohydroxylated metabolites in hair. Wide variations were observed for the concentrations of the naphthoylindole-based synthetic cannabinoids and metabolites in authentic hair samples from nine cases; those were 0.4-59.2 pg/mg for JWH-018, 0.1-0.8 pg/mg for JWH-073, 1.7-739.0 pg/mg for AM-2201, 0.1-402.0 pg/mg for JWH-122, 0.2-276.0 pg/mg for MAM-2201, 0.2-1.1 pg/mg for JWH-018 N-COOH, 0.3-37.2 pg/mg for JWH-018 N-5-OH, 0.3 pg/mg for JWH-073 N-COOH, 0.4 pg/mg for AM-2201 N-4-OH, 0.2-3.1 pg/mg for AM-2201 N-6-OHindole and 0.1-3.5 pg/mg for JWH-122 N-5-OH. This quantitative LC-MS/MS analytical method for five naphthoylindole-based synthetic cannabinoids and their metabolites was very useful to be applied to authentic hair samples, of which their analytical results suggested the incorporation of synthetic cannabinoids in the hair matrix and provided the information on ingested parent drugs. Copyright © 2014 Elsevier B.V. All rights reserved.
Rey, M D; Font, R; Aracil, I
2014-08-15
PCDD/F emissions from three light-duty diesel vehicles--two vans and a passenger car--have been measured in on-road conditions. We propose a new methodology for small vehicles: a sample of exhaust gas is collected by means of equipment based on United States Environmental Protection Agency (U.S. EPA) method 23 A for stationary stack emissions. The concentrations of O2, CO, CO2, NO, NO2 and SO2 have also been measured. Six tests were carried out at 90-100 km/h on a route 100 km long. Two additional tests were done during the first 10 min and the following 60 min of the run to assess the effect of the engine temperature on PCDD/F emissions. The emission factors obtained for the vans varied from 1800 to 8400 pg I-TEQ/Nm(3) for a 2004 model year van and 490-580 pg I-TEQ/Nm(3) for a 2006 model year van. Regarding the passenger car, one run was done in the presence of a catalyst and another without, obtaining emission factors (330-880 pg I-TEQ/Nm(3)) comparable to those of the modern van. Two other tests were carried out on a power generator leading to emission factors ranging from 31 to 78 pg I-TEQ/Nm(3). All the results are discussed and compared with literature. Copyright © 2014 Elsevier B.V. All rights reserved.
Atmospheric CO2 measurements reveal strong drought sensitivity of Amazonian carbon balance
NASA Astrophysics Data System (ADS)
Miller, J. B.; Gatti, L.; Gloor, M.; Doughty, C.; Malhi, Y.; Domingues, L. G.; Basso, L. S.; Martinewski, A.; Correia, C.; Borges, V.; Freitas, S. R.; Braz, R.; Anderson, L.; Rocha, H.; Grace, J.; Phillips, O.; Lloyd, J.
2013-12-01
Potential feedbacks between land carbon pools and climate are one of the largest sources of uncertainty for predicting future global climate, but estimates of their sensitivity to climate anomalies in the tropics and determination of underlying mechanisms are either incomplete or strongly model-based. Amazonia alone stores ~150-200 Pg of labile carbon, and has experienced an increasing trend in temperature and extreme floods and droughts over the last two decades. Here we report the first Amazon Basin-wide seasonal and annual carbon balances based on tropospheric greenhouse gas sampling, during an anomalously dry and a wet year, 2010 and 2011, providing the first whole-system assessment of sensitivity to such conditions. During 2010, the Amazon Basin lost 0.5×0.2 PgCyr-1 while in 2011 it was approximately carbon neutral (0.06×0.1 PgCyr-1). Carbon loss via fire was 0.5×0.1 PgCyr-1 in 2010 and 0.3×0.1 PgCyr-1 in 2011, as derived from Basin-wide carbon monoxide (CO) enhancements. Subtracting fire emissions from total carbon flux to derive Basin net biome exchange (NBE) reveals that in 2010 the non-fire regions of the Basin were carbon neutral; in 2011 they were a net carbon sink of -0.3×0.1 PgC yr-1, roughly consistent with a three-decade long intact-forest biomass sink of ~ -0.5×0.3 PgCyr-1 estimated from forest censuses. Altogether, our results suggest that if the recent trend of precipitation extremes persists, the Amazon region may become an increasing carbon source as a result of both emissions from fires and suppression of NBE by drought.
Dannon, Pinhas N.; Lowengrub, Katherine; Gonopolski, Yehudit; Musin, Ernest; Kotler, Moshe
2006-01-01
Pathological gambling (PG) is a prevalent and highly disabling impulse-control disorder. Two dominant phenomenological models for PG have been presented in the literature. According to one model, PG is included as an obsessive-compulsive spectrum disorder, while according to the second model, PG represents a form of nonpharmacologic addiction. In this article, we present an expanded conceptualization of the phenomenology of PG. On the basis of our clinical research experience and a review of data in the field, we propose 3 subtypes of pathological gamblers: the “impulsive” subtype, the “obsessive-compulsive” subtype, and the “addictive” subtype. We also review the current pharmacologic and nonpharmacologic treatment strategies for PG. A further aim of this article is to encourage awareness of the importance of improved screening procedures for the early detection of PG. PMID:17245454
Transport and fate of hexachlorocyclohexanes in the oceanic air and surface seawater
NASA Astrophysics Data System (ADS)
Xie, Z.; Koch, B. P.; Möller, A.; Sturm, R.; Ebinghaus, R.
2011-06-01
Hexachlorocyclohexanes (HCHs) are ubiquitous organic pollutants derived from pesticide application. They are subject to long-range transport, persistent in the environment, and capable of accumulation in biota. Shipboard measurements of HCH isomers (α-, γ- and β-HCH) in surface seawater and boundary layer atmospheric samples were conducted in the Atlantic and the Southern Ocean in October to December of 2008. ΣHCHs concentrations (the sum of α-, γ- and β-HCH) in the lower atmosphere ranged from 11.8 to 36.9 pg m-3 (mean: 26.6 ± 11.0 pg m-3) in the Northern Hemisphere (NH), and from 1.5 to 4.0 pg m-3 (mean: 2.8 ± 1.1 pg m-3) in the Southern Hemisphere (SH), respectively. Water concentrations were: α-HCH 0.33-46.8 pg l-1, γ-HCH 0.02-33.2 pg l-1 and β-HCH 0.11-2 pg l-1. HCH concentrations decreased from the North Atlantic to the Southern Ocean, indicating historical use of HCHs in the NH. Spatial distribution showed increasing concentrations from the equator towards North and South latitudes illustrating the concept of cold condensation and less interhemispheric mixing process. In comparison to concentrations measured in 1987-1999/2000, gaseous HCHs were slightly lower, while dissolved HCHs decreased by factor of 2-3 orders of magnitude. Air-water exchange gradients suggested net deposition for α-HCH (mean: 3759 pg m-2 day-1) and γ-HCH (mean: 1987 pg m-2 day-1), whereas β-HCH varied between equilibrium (volatilization: <0-12 pg m-2 day-1) and net deposition (range: 6-687 pg m-2 day-1), indicating a multi-hopper transport behavior. Climate change may significantly accelerate the releasing process of "old" HCHs from continental storage (e.g. soil, vegetation and high mountains) and drive long-range transport from sources to deposition in the open oceans. Biological productivities may interfere with the air-water exchange process as well. Consequently, further investigation is necessary to elucidate the long term trends and the biogeochemical turnover of HCHs in the oceanic environment.
Roongsattham, Peerapat; Morcillo, Fabienne; Jantasuriyarat, Chatchawan; Pizot, Maxime; Moussu, Steven; Jayaweera, Dasuni; Collin, Myriam; Gonzalez-Carranza, Zinnia H; Amblard, Philippe; Tregear, James W; Tragoonrung, Somvong; Verdeil, Jean-Luc; Tranbarger, Timothy J
2012-08-25
Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG) multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ) during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4) is the most highly induced in the fruit base, with a 700-5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit tissues contrast with data from tomato, suggesting functional divergence underlying the ripening and abscission processes has occurred between these two fruit species. Furthermore, phylogenetic analysis of EgPG4 with PGs from other species suggests some conservation, but also diversification has occurred between monocots and eudicots, in particular between dry and fleshy fruit species.
2012-01-01
Background Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG) multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. Results The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ) during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4) is the most highly induced in the fruit base, with a 700–5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. Conclusions The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit tissues contrast with data from tomato, suggesting functional divergence underlying the ripening and abscission processes has occurred between these two fruit species. Furthermore, phylogenetic analysis of EgPG4 with PGs from other species suggests some conservation, but also diversification has occurred between monocots and eudicots, in particular between dry and fleshy fruit species. PMID:22920238
Journal Article: Infant Exposure to Dioxin-Like Compounds in ...
A simple, one-compartment, first-order pharmacokinetic model is used to predict the infant body burden of dioxin-like compounds that results from breast-feeding. Validation testing of the model showed a good match between predictions and measurements of dioxin toxic equivalents (TEQs) in breast-fed infants, and the exercise highlighted the importance of the assumption of the rate of dissipation of TEQs in the infant. Five nursing scenarios were developed and evaluated within this modeling framework based on nursing duration: (1) non-nursing (i.e., formula only), (2) 6 weeks, (3), 6 months, (4) one year, and (5) two years. After nursing, the child is assumed to be exposed to background TEQ levels. It is further assumed that an infant weighs about 3.3 kg at birth and can be exposed to a total of 800 pg TEQ/day by consumption of breast milk, leading to an estimated body weight-based exposure of 242 pg TEQ/kg-day. After one year of breast-feeding, the exposure drops to about 18 pg TEQ/kg-day. This estimate considers declines in the concentrations of dioxins in mothers milk and infant body weight increases. This is significantly higher, on a body weight basis, than adult TEQ exposure, which are estimated to average about 1 pg TEQ/kg-day. For the 6 month and higher nursing scenarios, body burdens (expressed as a body lipid concentration) are predicted to peak at around 9 weeks at 44 ppt TEQ lipid. The formula-fed infants are predicted to have a body burden t
NASA Astrophysics Data System (ADS)
Ma, Xindong; Zhang, Haijun; Zhou, Hongqiang; Na, Guangshui; Wang, Zhen; Chen, Chen; Chen, Jingwen; Chen, Jiping
2014-06-01
Chlorinated paraffins (CPs) were measured in air samples at a remote air monitoring site established in Georgia King Island, Fildes Peninsula of Antarctica (Great Wall Station, China) to study the long-range atmospheric transport of these anthropogenic pollutants to the Antarctic. Gas- and particle-phase CPs were collected using polyurethane foam plugs (PUF) and glass fiber filters (GFF) respectively during summertime of 2012. The total atmospheric levels of SCCPs and MCCPs ranged from 9.6 to 20.8 pg m-3 (average: 14.9 pg m-3) and 3.7-5.2 pg m-3 (average: 4.5 pg m-3), respectively. C10 and C11 carbon chain homologues with Cl5 and Cl6 chlorine atoms predominated in SCCP formula groups both in gas- and particle-phase. Significant linear correlation was found between gas/particle partition coefficients (KP) and sub-cooled liquid vapor pressures (pL°) (R2 = 0.437, p < 0.01), as well as KP and octanol-air partition coefficients (KOA) (R2 = 0.442, p < 0.01). Absolute slope values of two regression models (0.31 and 0.39) were less than 0.6 indicating that the way of absorption into organic matter of aerosol played a more important role on atmospheric partitioning and transferring of CPs in remote Antarctic area. Both the Junge-Pankow model and the KOA-based model tended to underestimate the sorption of lower chlorinated CPs and overestimate the sorption of highly chlorinated CPs.
NASA Astrophysics Data System (ADS)
Echeverri, J. D.; Siqueira, M. B.
2013-05-01
Managed Forests have important roles in climate change due to their contribution to CO2 sequestration stored in their biomass, soils and products therefrom. Terrestrial net primary production (NPP, kgC/m2), equal to gross primary production minus autotrophic respiration, represents the carbon available for plant allocation to leaves, stems, roots, defensive compounds, and reproduction and is the basic measure of biological productivity. Tree growth, food production, fossil fuel production, and atmospheric CO2 levels are all strongly controlled by NPP. Accurate quantification of NPP at local to global scales is therefore central topic for carbon cycle researchers, foresters, land and resource managers, and politicians. For recent or current NPP estimates, satellite remote sensing can be used but for future climate scenarios, simulation models are required. There is an increasing trend to displace natural Brazilian Cerrado to Eucalyptus for paper mills and energy conversion from biomass. The objective of this research exercise is to characterize NPP from managed Eucalyptus plantation in the Brazilian Cerrado. The models selected for this study were the 3-PG and Biome-BGC. The selection of these models aims to cover a range of complexity that allow the evaluation of the processes modeled as to its relevance to a best estimate of productivity in eucalyptus forests. 3-PG model is the simplest of the models chosen for this exercise. Its main purpose is to estimate productivity of forests in timber production. The model uses the relationship of quantum efficiency in the transformation of light energy into biomass for vegetative growth calculations in steps in time of one month. Adverse weather conditions are treated with reduction factors applied in the top efficiency. The second model is the Biome-BGC that uses biology and geochemistry principles to estimate leaf-level photosynthesis based on limiting factors such as availability of light and nutrient constraints. The model does not consider any vertical structure, and the extrapolation of leaf scale is the scale of the ecosystem, which is accomplished by using leaf area index to variable on a temporal resolution of a day. Carbon allocation is computed by complex interactions between multiples carbon pools. Therefore the results obtained in modeling, it was possible to verify the applicability of the two models 3PG and Biome-BGC in estimate of NPP to eucalyptus energy forest in a Brazilian cerrado region, having a strong correlation to the sixth year of forest growth between the two models. The study also revealed that have input parameters in models that need to be measured with a good accuracy, because in function of these parameters, the NPP variation is very large. Finally the study revealed the importance of confronting the data obtained by 3PG and Biome-BGC with experimental data to improve performance modeled-based estimation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Min; Zhuang, Qianlai; Cook, D.
2011-08-31
Satellite remote sensing provides continuous temporal and spatial information of terrestrial ecosystems. Using these remote sensing data and eddy flux measurements and biogeochemical models, such as the Terrestrial Ecosystem Model (TEM), should provide a more adequate quantification of carbon dynamics of terrestrial ecosystems. Here we use Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI), Land Surface Water Index (LSWI) and carbon flux data of AmeriFlux to conduct such a study. We first modify the gross primary production (GPP) modeling in TEM by incorporating EVI and LSWI to account for the effects of the changes of canopy photosynthetic capacity, phenologymore » and water stress. Second, we parameterize and verify the new version of TEM with eddy flux data. We then apply the model to the conterminous United States over the period 2000-2005 at a 0.05-0.05 spatial resolution. We find that the new version of TEM made improvement over the previous version and generally captured the expected temporal and spatial patterns of regional carbon dynamics. We estimate that regional GPP is between 7.02 and 7.78 PgC yr{sup -1} and net primary production (NPP) ranges from 3.81 to 4.38 Pg Cyr{sup -1} and net ecosystem production (NEP) varies within 0.08- 0.73 PgC yr{sup -1} over the period 2000-2005 for the conterminous United States. The uncertainty due to parameterization is 0.34, 0.65 and 0.18 PgC yr{sup -1} for the regional estimates of GPP, NPP and NEP, respectively. The effects of extreme climate and disturbances such as severe drought in 2002 and destructive Hurricane Katrina in 2005 were captured by the model. Our study provides a new independent and more adequate measure of carbon fluxes for the conterminous United States, which will benefit studies of carbon-climate feedback and facilitate policy-making of carbon management and climate.« less
NASA Astrophysics Data System (ADS)
Tan, Kun; Ciais, Philippe; Piao, Shilong; Wu, Xiaopu; Tang, Yanhong; Vuichard, Nicolas; Liang, Shuang; Fang, Jingyun
2010-03-01
The cold grasslands of the Qinghai-Tibetan Plateau form a globally significant biome, which represents 6% of the world's grasslands and 44% of China's grasslands. Yet little is known about carbon cycling in this biome. In this study, we calibrated and applied a process-based ecosystem model called Organizing Carbon and Hydrology in Dynamic Ecosystems (ORCHIDEE) to estimate the C fluxes and stocks of these grasslands. First, the parameterizations of ORCHIDEE were improved and calibrated against multiple time-scale and spatial-scale observations of (1) eddy-covariance fluxes of CO2 above one alpine meadow site; (2) soil temperature collocated with 30 meteorological stations; (3) satellite leaf area index (LAI) data collocated with the meteorological stations; and (4) soil organic carbon (SOC) density profiles from China's Second National Soil Survey. The extensive SOC survey data were used to extrapolate local fluxes to the entire grassland biome. After calibration, we show that ORCHIDEE can successfully capture the seasonal variation of net ecosystem exchange (NEE), as well as the LAI and SOC spatial distribution. We applied the calibrated model to estimate 0.3 Pg C yr-1 (1 Pg = 1015 g) of total annual net primary productivity (NPP), 0.4 Pg C of vegetation total biomass (aboveground and belowground), and 12 Pg C of SOC stocks for Qinghai-Tibetan grasslands covering an area of 1.4 × 106 km2. The mean annual NPP, vegetation biomass, and soil carbon stocks decrease from the southeast to the northwest, along with precipitation gradients. Our results also suggest that in response to an increase of temperature by 2°C, approximately 10% of current SOC stocks in Qinghai-Tibetan grasslands could be lost, even though NPP increases by about 9%. This result implies that Qinghai-Tibetan grasslands may be a vulnerable component of the terrestrial carbon cycle to future climate warming.
Contribution of soil respiration to the global carbon equation.
Xu, Ming; Shang, Hua
2016-09-20
Soil respiration (Rs) is the second largest carbon flux next to GPP between the terrestrial ecosystem (the largest organic carbon pool) and the atmosphere at a global scale. Given their critical role in the global carbon cycle, Rs measurement and modeling issues have been well reviewed in previous studies. In this paper, we briefly review advances in soil organic carbon (SOC) decomposition processes and the factors affecting Rs. We examine the spatial and temporal distribution of Rs measurements available in the literature and found that most of the measurements were conducted in North America, Europe, and East Asia, with major gaps in Africa, East Europe, North Asia, Southeast Asia, and Australia, especially in dry ecosystems. We discuss the potential problems of measuring Rs on slope soils and propose using obliquely-cut soil collars to solve the existing problems. We synthesize previous estimates of global Rs flux and find that the estimates ranged from 50 PgC/yr to 98 PgC/yr and the error associated with each estimation was also high (4 PgC/yr to 33.2 PgC/yr). Using a newly integrated database of Rs measurements and the MODIS vegetation map, we estimate that the global annual Rs flux is 94.3 PgC/yr with an estimation error of 17.9 PgC/yr at a 95% confidence level. The uneven distribution of Rs measurements limits our ability to improve the accuracy of estimation. Based on the global estimation of Rs flux, we found that Rs is highly correlated with GPP and NPP at the biome level, highlighting the role of Rs in global carbon budgets. Copyright © 2016. Published by Elsevier GmbH.
Yang, Yanqiu; He, Fupo; Ye, Jiandong
2016-12-01
In this study, phosphate-based glass (PG) was used as a sintering aid for freeze-cast porous biphasic calcium phosphate (BCP) ceramic, which was sintered under a lower temperature (1000°C). The phase composition, pore structure, compressive strength, and cytocompatibility of calcium phosphate composite ceramics (PG-BCP) were evaluated. The results indicated that PG additive reacted with calcium phosphate during the sintering process, forming β-Ca2P2O7; the ions of sodium and magnesium from PG partially substituted the calcium sites of β-calcium phosphate in BCP. The PG-BCP showed good cytocompatibility. The pore width of the porous PG-BCP ceramics was around 50μm, regardless of the amount of PG sintering aid. As the content of PG increased from 0wt.% to 15wt.%, the compressive strength of PG-BCP increased from 0.02 MP to 0.28MPa. When the PG additive was 17.5wt.%, the compressive strength of PG-BCP dramatically increased to 5.66MPa. Addition of 15wt.% PG was the critical point for the properties of PG-BCP. PG is considered as an effective sintering aid for freeze-cast porous bioceramics. Copyright © 2016 Elsevier B.V. All rights reserved.
Nakamura, Suguru; Shioya, Koki; Hiraoka, B Yukihiro; Suzuki, Nao; Hoshino, Tomonori; Fujiwara, Taku; Yoshinari, Nobuo; Ansai, Toshihiro; Yoshida, Akihiro
2018-04-01
Porphyromonas gingivalis produces hydrogen sulfide (H2S) from l-cysteine. However, the role of H2S produced by P. gingivalis in periodontal inflammation is unclear. In this study, we identified the enzyme that catalyses H2S production from l-cysteine and analysed the role of H2S using a mouse abscess model. The enzyme identified was identical to methionine γ-lyase (PG0343), which produces methyl mercaptan (CH3SH) from l-methionine. Therefore, we analysed H2S and CH3SH production by P. gingivalis W83 and a PG0343-deletion mutant (ΔPG0343) with/without l-cysteine and/or l-methionine. The results indicated that CH3SH is produced constitutively irrespective of the presence of l-methionine, while H2S was greatly increased by both P. gingivalis W83 and ΔPG0343 in the presence of l-cysteine. In contrast, CH3SH production by ΔPG0343 was absent irrespective of the presence of l-methionine, and H2S production was eliminated in the absence of l-cysteine. Thus, CH3SH and H2S production involves different substrates, l-methionine or l-cysteine, respectively. Based on these characteristics, we analysed the roles of CH3SH and H2S in abscess formation in mice by P. gingivalis W83 and ΔPG0343. Abscess formation by P. gingivalis W83, but not ΔPG0343, differed significantly in the presence and absence of l-cysteine. In addition, the presence of l-methionine did not affect the size of abscesses generated by P. gingivalis W83 and ΔPG0343. Therefore, we conclude that H2S produced by P. gingivalis does not induce inflammation; however, H2S enhances inflammation caused by CH3SH. Thus, these results suggest the H2S produced by P. gingivalis plays a supportive role in inflammation caused by methionine γ-lyase.
Changes in terrestrial CO2 budget in Siberia in the past three decades
NASA Astrophysics Data System (ADS)
Ichii, K.; Kondo, M.; Ueyama, M.; Ito, A.; Kobayashi, H.; Maksyutov, S. S.; Maki, T.; Nakamura, T.; Niwa, Y.; Patra, P. K.; Saeki, T.; Sato, H.; Sasai, T.; Saigusa, N.; Tian, H.; Yanagi, Y.; Zhang, B.
2015-12-01
Siberia is one of the regions where significant warming is proceeding, and the warming might cause changes in terrestrial carbon cycle. We analyzed interannual and decadal changes in terrestrial CO2 fluxes in the regions using multiple data sets, such as empirically estimated carbon fluxes based on multiple eddy-covariance sites (empirical upscaling; Support Vector Regression with AsiaFlux data), satellite-based vegetation index data, multiple terrestrial carbon cycle models from Asia-MIP (e.g. BEAMS, Biome-BGC, SEIB-DGVM, and VISIT), and atmospheric inverse models (e.g. ACTM, JMA, NICAM-TM) for the past 3 decades (1980s, 1990s, and 2000s). First, we checked the consistency in interannual variation of net carbon exchange between empirical upscaling and Asia-MIP model for 2001-2011 period, and found these two estimations show overall consistent interannual variation. Second, we analyzed net carbon exchange form Asia-MIP models and atmospheric inversions for the past three decades, and found persistent increases in terrestrial CO2 sink from two estimates. Magnitudes of estimated terrestrial CO2 sinks are also consistent (e.g. Asia-MIP: 0.2 PgC yr-1 in 1980s and 0.3 PgC yr-1 in 2000s and Inversions: 0.2 PgC yr-1 in 1980s and 0.5 PgC/yr in 2000s). We further analyzed the cause of persistent increases in CO2 uptake in the region using Asia-MIP model outputs, and climate changes (both warming and increases in water availability) and CO2 fertilization plays almost equivalent roles in sink increases. In addition, both gross primary productivity (GPP) and ecosystem respiration (RE) were increased, but increase in GPP was larger than that in RE.
NASA Astrophysics Data System (ADS)
McGuire, A. D.
2014-12-01
We conducted an assessment of changes in permafrost area and carbon storage simulated by process-based models between 1960 and 2300. The models participating in this comparison were those that had joined the model integration team of the Vulnerability of Permafrost Carbon Research Coordination Network (see http://www.biology.ufl.edu/permafrostcarbon/). Each of the models in this comparison conducted simulations over the permafrost land region in the Northern Hemisphere driven by CCSM4-simulated climate for RCP 4.5 and 8.5 scenarios. Among the models, the area of permafrost (defined as the area for which active layer thickness was less than 3 m) ranged between 13.2 and 20.0 million km2. Between 1960 and 2300, models indicated the loss of permafrost area between 5.1 to 6.0 million km2 for RCP 4.5 and between 7.1 and 15.2 million km2 for RCP 8.5. Among the models, the density of soil carbon storage in 1960 ranged between 13 and 42 thousand g C m-2; models that explicitly represented carbon with depth had estimates greater than 27 thousand g C m-2. For the RCP 4.5 scenario, changes in soil carbon between 1960 and 2300 ranged between losses of 32 Pg C to gains of 58 Pg C, in which models that explicitly represent soil carbon with depth simulated losses or lower gains of soil carbon in comparison with those that did not. For the RCP 8.5 scenario, changes in soil carbon between 1960 and 2300 ranged between losses of 642 Pg C to gains of 66 Pg C, in which those models that represent soil carbon explicitly with depth all simulated losses, while those that do not all simulated gains. These results indicate that there are substantial differences in responses of carbon dynamics between model that do and do not explicitly represent soil carbon with depth in the permafrost region. We present analyses of the implications of the differences for atmospheric carbon dynamics at multiple temporal scales between 1960 and 2300.
Laube, Beth L.; Afshar-Mohajer, Nima; Koehler, Kirsten; Chen, Gang; Lazarus, Philip; Collaco, Joseph M.; McGrath-Morrow, Sharon A.
2017-01-01
Objective To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. Methods C57BL/6 male mice (age 10.5 ±2.4 weeks) were exposed for 20min/day to E-cigarette aerosol generated by a Joyetech 510-T® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99mtechnetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. Results MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6±5.2%, 7.5±2.8% and 11.2±5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ±8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ±4.6)% (p < .05). Serum cotinine levels were <0.5ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. Conclusions In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine. PMID:28651446
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Hanqin; Lu, Chaoqun; Yang, Jia
2015-06-05
Soil is the largest organic carbon (C) pool of terrestrial ecosystems, and loss from soil accounts for a large pro portion of land-atmosphere C exchange. Due to large pool size and variable residence time from years to millennia, even small changes in soil organic C(SOC) have substantial effects on the terrestrial C budget, thereby affecting atmospheric carbon dioxide (CO2)concentration and climate change. In the past decades, a wide variety of studies have been conducted to quantify global SOC stocks and soil exchange with the atmosphere through site measurements, inventories, and empirical/process-based modeling. However, these estimates are highly uncertain and identifyingmore » major driving forces controlling soil C storage and fluxes remains a key research challenge his study has compiled century-long (1901-2010)estimates of SOC storage and heterotrophic respiration (Rh) from ten terrestrial biosphere models (TBMs) in the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) and two observation based datasets. The ten-TBM ensemble shows that global SOC estimate range from 4 to 2111 Pg C (1 Pg = 10 15g) with a median value of 1158 Pg C33 in 2010. Modeling approach estimates a broad range of Rh from 35 to 69 Pg C yr -1 with a median value of 51Pg C yr -1 during 200–2010. The largest uncertainty in SOC stocks exists in the 40–65°N latitude band while Rh differences are the largest in the tropics. All the models agreed that climate and land use changes have decreased SOC stocks while elevated CO 2 and atmospheric nitrogen deposition have increased SOC stocks though the response varied significantly among models. Model representations of temperature and moisture sensitivity,nutrient limitation and land use partially explain the divergent estimates of global SOC stocks and soil fluxes in this study. In addition, major sources of uncertainty from model estimation include exclusion of SOC storage in wetlands and peatlands as well as C storage in deep soil layers.« less
A molecular model of proteoglycan-associated electrostatic forces in cartilage mechanics.
Buschmann, M D; Grodzinsky, A J
1995-05-01
Measured values of the swelling pressure of charged proteoglycans (PG) in solution (Williams RPW, and Comper WD; Biophysical Chemistry 36:223, 1990) and the ionic strength dependence of the equilibrium modulus of PG-rich articular cartilage (Eisenberg SR, and Grodzinsky AJ; J Orthop Res 3: 148, 1985) are compared to the predictions of two models. Each model is a representation of electrostatic forces arising from charge present on spatially fixed macromolecules and spatially mobile micro-ions. The first is a macroscopic continuum model based on Donnan equilibrium that includes no molecular-level structure and assumes that the electrical potential is spatially invariant within the polyelectrolyte medium (i.e. zero electric field). The second model is based on a microstructural, molecular-level solution of the Poisson-Boltzmann (PB) equation within a unit cell containing a charged glycosaminoglycan (GAG) molecule and its surrounding atmosphere of mobile ions. This latter approach accounts for the space-varying electrical potential and electrical field between the GAG constituents of the PG. In computations involving no adjustable parameters, the PB-cell model agrees with the measured pressure of PG solutions to within experimental error (10%), whereas the ideal Donnan model overestimates the pressure by up to 3-fold. In computations involving one adjustable parameter for each model, the PB-cell model predicts the ionic strength dependence of the equilibrium modulus of articular cartilage. Near physiological ionic strength, the Donnan model overpredicts the modulus data by 2-fold, but the two models coincide for low ionic strengths (C0 < 0.025M) where the spatially invariant Donnan potential is a closer approximation to the PB potential distribution. The PB-cell model result indicates that electrostatic forces between adjacent GAGs predominate in determining the swelling pressure of PG in the concentration range found in articular cartilage (20-80 mg/ml). The PB-cell model is also consistent with data (Eisenberg and Grodzinsky, 1985, Lai WM, Hou JS, and Mow VC; J Biomech Eng 113: 245, 1991) showing that these electrostatic forces account for approximately 1/2 (290kPa) the equilibrium modulus of cartilage at physiological ionic strength while absolute swelling pressures may be as low as approximately 25-100kPa. This important property of electrostatic repulsion between GAGs that are highly charged but spaced a few Debye lengths apart allows cartilage to resist compression (high modulus) without generating excessive intratissue swelling pressures.
Khairy, Mohammed A; Luek, Jenna L; Dickhut, Rebecca; Lohmann, Rainer
2016-09-01
The Antarctic continent is among the most pristine regions; yet various organic contaminants have been measured there routinely. Air and snow samples were collected during the austral spring (October-November, 2010) along the western Antarctic Peninsula and analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) to assess the relative importance of long-range transport versus local primary or secondary emissions. Highest concentrations of PCBs, PBDEs and DDTs were observed in the glacier's snow sample, highlighting the importance of melting glaciers as a possible secondary source of legacy pollutants to the Antarctic. In the atmosphere, contaminants were mainly found in the vapor phase (>65%). Hexachlorobenzene (33.6 pg/m(3)), PCBs (11.6 pg/m(3)), heptachlor (5.64 pg/m(3)), PBDEs (4.22 pg/m(3)) and cis-chlordane (2.43 pg/m(3)) were the most abundant contaminants. In contrast to other compounds, PBDEs seem to have originated from local sources, possibly the research station itself. Gas-particle partitioning for analytes were better predicted using the adsorption partitioning model than an octanol-based absorption approach. Diffusive flux calculations indicated that net deposition is the dominant pathway for PBDEs and chlordanes, whereas re-volatilization from snow (during melting or metamorphosis) was observed for PCBs and some OCPs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Copper-phospholipid interaction at cell membrane model hydrophobic surfaces.
Mlakar, Marina; Cuculić, Vlado; Frka, Sanja; Gašparović, Blaženka
2018-04-01
Detailed investigation of Cu (II) binding with natural lipid phosphatidylglycerol (PG) in aqueous solution was carried out by voltammetric measurements at the mercury drop electrode, complemented by monolayer studies in a Langmuir trough and electrophoretic measurements, all used as models for hydrophobic cell membranes. Penetration of copper ions into the PG layer was facilitated by the formation of hydrophilic Cu-Phenanthroline (Phen) complex in the subphase, followed by the mixed ligand Cu-Phen-PG complex formation at the hydrophobic interface. Electrophoretic measurements indicated a comparatively low abundance of the formed mixed ligand complex within the PG vesicles, resulting it the zeta potential change of +0.83mV, while monolayer studies confirmed their co-existence at the interface. The Cu-Phen-PG complex was identified in the pH range from 6 to 9. The stoichiometry of the complex ([PhenCuOHPG]), as well as its stability and kinetics of formation, were determined at the mercury drop electrode. Cu-Phen-PG reduces quasireversibly at about -0.7V vs. Ag/AgCl including reactant adsorption, followed by irreversible mixed complex dissociation, indicating a two-electron transfer - chemical reaction (EC mechanism). Consequently, the surface concentration (γ) of the adsorbed [PhenCuOHPG] complex at the hydrophobic electrode surface was calculated to be (3.35±0.67)×10 -11 molcm -2 . Information on the mechanism of Cu (II) - lipid complex formation is a significant contribution to the understanding of complex processes at natural cell membranes. Copyright © 2017 Elsevier B.V. All rights reserved.
Anthropogenic nitrogen emissions during the Holocene and their possible effects on remote ecosystems
NASA Astrophysics Data System (ADS)
KopáčEk, Jiří; Posch, Maximilian
2011-06-01
Reactive nitrogen (Nr = NH3-N + NOx-N) is an important atmospheric pollutant, contributing to acidification, eutrophication and biodiversity changes in ecosystems. This study estimates Nr emissions from anthropogenic sources on a global scale since the advent of agriculture ˜8000 B.C., using a simple model based on the development of human population and per capita factors of Nr emissions originating from livestock production, biomass burning (biofuel use and forest and savannah burning), and other anthropogenic sources (humans and pets, N-fertilizer use, and fossil fuel combustion). The estimated global cumulative anthropogenic emissions of Nr to the atmosphere are ˜17.4 Pg N (8.6 Pg NH3-N and 8.8 Pg NOx-N) for 8000 B.C. through the year 2000 A.D., with 28% of this amount emitted during 1850-2000 A.D., 42% during 1-1850 A.D., and 30% during the previous 8000 years. Forest and savannah burning represent the major cumulative flux of both NH3-N and NOx-N (3.5 and 5.8 Pg, respectively). Livestock production and biofuel burning are responsible for emissions of 3.3 and 1.2 Pg NH3-N, respectively, while the application of synthetic fertilizers contributes 0.26 Pg NH3-N. The different duration of biofuel and fossil fuel use (10,000 versus ˜150 years) causes the higher cumulative NOx-N emissions from biofuel than from fossil fuel use (1.9 versus 1.1 Pg). The cumulative Nr emissions on a land area basis are 1.3 and 3.0 Mg N ha-1 globally and in Europe, respectively. Since an estimated 60% of Nr emitted in Europe is also deposited there, the average cumulative anthropogenic Nr deposition would be ˜1.8 Mg N ha-1, representing ˜30% of the current N pools in forest and alpine meadow soils of European glaciated areas (i.e., soils of similar age as the emissions). Despite large uncertainties in the model (13.7-30.5 Pg N over the last 10,000 years), the relative temporal distributions of total cumulative Nr emissions vary within relatively narrow ranges for different assumptions, with 70%-84% of the emissions occurring prior to 1850 A.D. We conclude that the majority of the total cumulative Nr flux from anthropogenic sources over the last 10,000 years occurred in the preindustrial period and could have increased soil N pools of some remote ecosystems much earlier than is currently assumed.
Afrin, Sadia; Zhu, Jie; Cao, Hongzhe; Huang, Jingjia; Xiu, Hao; Luo, Tiao; Luo, Zhiyong
2015-04-01
The v-myb avian myeloblastosis viral oncogene homolog (MYB) family constitutes one of the most abundant groups of transcription factors and plays vital roles in developmental processes and defense responses in plants. A ginseng (Panax ginseng C.A. Meyer) MYB gene was cloned and designated as PgMYB1. The cDNA of PgMYB1 is 762 base pairs long and encodes the R2R3-type protein consisting 238 amino acids. Subcellular localization showed that PgMYB1-mGFP5 fusion protein was specifically localized in the nucleus. To understand the functional roles of PgMYB1, we investigated the expression patterns of PgMYB1 in different tissues and under various conditions. Quantitative real-time polymerase chain reaction and western blot analysis showed that PgMYB1 was expressed at higher level in roots, leaves, and lateral roots than in stems and seeds. The expression of PgMYB1 was up-regulated by abscisic acid, salicylic acid, NaCl, and cold (chilling), and down-regulated by methyl jasmonate. These results suggest that PgMYB1 might be involved in responding to environmental stresses and hormones. © The Author 2015. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.
Kervadec, Anaïs; Bellamy, Valérie; El Harane, Nadia; Arakélian, Lousineh; Vanneaux, Valérie; Cacciapuoti, Isabelle; Nemetalla, Hany; Périer, Marie-Cécile; Toeg, Hadi D; Richart, Adèle; Lemitre, Mathilde; Yin, Min; Loyer, Xavier; Larghero, Jérôme; Hagège, Albert; Ruel, Marc; Boulanger, Chantal M; Silvestre, Jean-Sébastien; Menasché, Philippe; Renault, Nisa K E
2016-06-01
Cell-based therapies are being explored as a therapeutic option for patients with chronic heart failure following myocardial infarction. Extracellular vesicles (EV), including exosomes and microparticles, secreted by transplanted cells may orchestrate their paracrine therapeutic effects. We assessed whether post-infarction administration of EV released by human embryonic stem cell-derived cardiovascular progenitors (hESC-Pg) can provide equivalent benefits to administered hESC-Pg and whether hESC-Pg and EV treatments activate similar endogenous pathways. Mice underwent surgical occlusion of their left coronary arteries. After 2-3 weeks, 95 mice included in the study were treated with hESC-Pg, EV, or Minimal Essential Medium Alpha Medium (alpha-MEM; vehicle control) delivered by percutaneous injections under echocardiographic guidance into the peri-infarct myocardium. functional and histologic end-points were blindly assessed 6 weeks later, and hearts were processed for gene profiling. Genes differentially expressed between control hearts and hESC-Pg-treated and EV-treated hearts were clustered into functionally relevant pathways. At 6 weeks after hESC-Pg administration, treated mice had significantly reduced left ventricular end-systolic (-4.20 ± 0.96 µl or -7.5%, p = 0.0007) and end-diastolic (-4.48 ± 1.47 µl or -4.4%, p = 0.009) volumes compared with baseline values despite the absence of any transplanted hESC-Pg or human embryonic stem cell-derived cardiomyocytes in the treated mouse hearts. Equal benefits were seen with the injection of hESC-Pg-derived EV, whereas animals injected with alpha-MEM (vehicle control) did not improve significantly. Histologic examination suggested a slight reduction in infarct size in hESC-Pg-treated animals and EV-treated animals compared with alpha-MEM-treated control animals. In the hESC-Pg-treated and EV-treated groups, heart gene profiling identified 927 genes that were similarly upregulated compared with the control group. Among the 49 enriched pathways associated with these up-regulated genes that could be related to cardiac function or regeneration, 78% were predicted to improve cardiac function through increased cell survival and/or proliferation or DNA repair as well as pathways related to decreased fibrosis and heart failure. In this post-infarct heart failure model, either hESC-Pg or their secreted EV enhance recovery of cardiac function and similarly affect cardiac gene expression patterns that could be related to this recovery. Although the mechanisms by which EV improve cardiac function remain to be determined, these results support the idea that a paracrine mechanism is sufficient to effect functional recovery in cell-based therapies for post-infarction-related chronic heart failure. Copyright © 2016 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, Dongming; Ye, Ke; Cao, Dianxue; Yin, Jinling; Cheng, Kui; Wang, Bin; Xu, Yang; Wang, Guiling
2015-01-01
A piece of flexible and conductive A4 paper is prepared by coating a layer of graphite with a normal 8B pencil. Then, Co nano-plates and Pd are assembled by a simple electrodeposition and chemical-reduction methods on the surface of the electrified paper, respectively. The as-prepared paper substrate/graphite-Co film-Pd (PG-CoPd) electrode is characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer, transmission electron microscope and X-ray diffractometer. The catalytic activity of the PG-CoPd electrode for H2O2 electroreduction is investigated by means of cyclic voltammetry and chronoamperometry. The preparation process of the PG-CoPd electrode does not use any binder and it exhibits a three dimensional (3D) nano structure, high stability and good electric conductivity. The mass of the Pd in PG-CoPd is about 0.0535 mg cm-2 and the reduction current density reaches to -4.30 A cm-2 mg-1 in 1 mol dm-3 NaOH and 1.4 mol dm-3 H2O2 at -0.5 V, which is higher than our previous reports of Au/Pd modified Co electrode.
NASA Astrophysics Data System (ADS)
Dubey, M. K.; Parker, H. A.; Wennberg, P. O.; Wunch, D.; Jacobson, A. R.; Kawa, S. R.; Keppel-Aleks, G.; Basu, S.; O'Dell, C.; Frankenberg, C.; Michalak, A. M.; Baker, D. F.; Christofferson, B.; Restrepo-Coupe, N.; Saleska, S. R.; De Araujo, A. C.; Miller, J. B.
2016-12-01
The Amazon basin stores 150-200 PgC, exchanges 18 PgC with the atmosphere every year and has taken up 0.42-0.65 PgC/y over the past two decades. Despite its global significance, the response of the tropical carbon cycle to climate variability and change is ill constrained as evidenced by the large negative and positive feedbacks in future climate simulations. The complex interplay of radiation, water and ecosystem phenology remains unresolved in current tropical ecosystem models. We use high frequency regional scale TCCON observations of column CO2, CO and CH4 near Manaus, Brazil that began in October 2014 to understand the aforementioned interplay of processes in regulating biosphere-atmosphere exchange. We observe a robust daily column CO2 uptake of about 2 ppm (4 ppm to 0.5 ppm) over 8 hours and evaluate how it changes as we transition to the dry season. Back-trajectory calculations show that the daily CO2 uptake footprint is terrestrial and influenced by the heterogeneity of the Amazon rain forests. The column CO falls from above 120 ppb to below 80 ppb as we transition from the biomass burning to wet seasons. The daily mean column CO2 rises by 3 ppm from October through June. Removal of biomass burning, secular CO2 increase and variations from transport (by Carbon tracker simulations) implies an increase of 2.3 ppm results from tropical biospheric processes (respiration and photosynthesis). This is consistent with ground-based remote sensing and eddy flux observations that indicate that leaf development and demography drives the tropical carbon cycle in regions that are not water limited and is not considered in current models. We compare our observations with output from 7 CO2 inversion transport models with assimilated meteorology and find that while 5 models reproduce the CO2 seasonal cycle all of them under predict the daily drawdown of CO2 by a factor of 3. This indicates that the CO2 flux partitioning between photosynthesis and respiration is incorrect in current models and needs refinement. Finally, we use OCO-2 column CO2 and Solar Induced Fluorescence observations over the Amazon to elucidate the tropical carbon cycle mechanisms at larger scales.
Buckley, M G; Marcus, N J; Yacoub, M H
1999-12-01
Brain natriuretic peptide (BNP), atrial natriuretic peptide (ANP) and N-terminal ANP are good research indices of the severity of heart failure. The stability of these peptides at room temperature has become an important factor in assessing their use as indicators of cardiac function in routine clinical practice. Inhibitors such as aprotinin are routinely added in the blood collection process, but may provide no benefit in sample collection and routine clinical practice. We assessed the stability of BNP, ANP and N-terminal ANP in blood samples collected in either the presence or the absence of the protease inhibitor aprotinin. Blood, either with or without aprotinin, was processed immediately (initial; 0 h) and after blood samples had been left for 3 h, 2 days or 3 days at room temperature. These times were chosen to reflect processing in a hospital outpatient clinic (2-3 h), or when posted from general practice (2-3 days). Initial plasma BNP, ANP and N-terminal ANP levels in the absence of aprotinin were 28.2+/-5.4, 44.2+/-7.9 and 1997+/-608 pg/ml respectively, and were not significantly different from initial values in the presence of aprotinin (29.0+/-5.9, 45.2+/-8.0 and 2009+/-579 pg/ml respectively). After 3 h at room temperature, there was a significant fall in ANP in the absence of aprotinin (36. 7+/-7.9 pg/ml; P<0.005), but not in the presence of aprotinin (41. 2+/-7.6 pg/ml). Both BNP and N-terminal ANP were unchanged in either the absence (BNP, 27.6+/-5.5 pg/ml; N-terminal ANP, 2099+/-613 pg/ml) or the presence (BNP, 29.4+/-5.6 pg/ml; N-terminal ANP, 1988+/-600 pg/ml) of aprotinin. After 2 days at room temperature, ANP had fallen significantly in both the absence (16.9+/-3.4 pg/ml) and the presence (24.0+/-5.0 pg/ml) of aprotinin compared with initial values, and there was a significant difference in ANP levels in the absence and presence of aprotinin (P<0.001). ANP levels had decreased further after 3 days at room temperature, to 11.9+/-3.4 pg/ml (no aprotinin) and 20.3+/-5.0 pg/ml (aprotinin added); these values were significantly different (P=0.002). In contrast, there was no change in the levels of BNP or N-terminal ANP after 2 or 3 days at room temperature, in either the absence or the presence of aprotinin. These studies indicate that aprotinin adds little benefit to the stability of cardiac peptides at room temperature. Blood samples for BNP and N-terminal ANP measurement used as a test of heart function in hospital clinics and by general practitioners in the community could be taken into blood tubes containing only EDTA as anticoagulant and without the additional step of adding the routinely used inhibitor aprotinin.
New observations and asteroseismic analysis of the subdwarf B pulsator PG 1219+534
NASA Astrophysics Data System (ADS)
Grootel, Valérie Van; Péters, Marie-Julie; Green, Elizabeth M.; Charpinet, Stéphane; Brassard, Pierre; Fontaine, Gilles
2018-03-01
We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3- month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric parameters from high S/N low and medium resolution spectroscopy. On the basis of the nine independent pulsation periods extracted from the photometric light curve, we carried out an astroseismic analysis by applying the forward modeling approach using our latest (third and fourth generation) sdB models. Atmospheric parameters (Teff = 34 258 ± 170 K, log g = 5.838 ± 0.030) were used as independent constraints, as well as partial mode identification based on observed multiplet structures we ascribed to stellar rotation. The optimal model found is remarkably consistent between various analyses with third and fourth generation of sdB models, and also with previously published analysis with second generation sdB models. It corresponds to a sdB with a canonical mass (0.46 ± 0.02 M⊙), rather thin H-He envelope (log q(envl) = -3.75 ± 0.12), and close to He-burning exhaustion (Xcore(C + O) = 0.86 ± 0.05).We also investigate the internal rotation of the star.We find that PG 1219+534 rotates very slowly (Prot = 34.91 ± 0.84 days) and that solid-body rotation is reached at least down to ˜60% of the radius.
Arjamaa, Olli; Pöllönen, Matti; Kinnunen, Kati; Ryhänen, Tuomas; Kaarniranta, Kai
2011-01-01
The purpose was to assess the activity of nuclear factor (NF)-κB and hypoxia inducible factor (HIF)-1α transcription factors and the expression levels of inflammation markers [interleukin (IL)-6 and IL-8] in the vitreous of patients suffering from proliferative diabetic retinopathy (PDR) scheduled for elective vitreous surgery in a single academic-based retina practice in a prospective clinical study. Twenty-seven patients with PDR were enrolled in the study. The severity of retinopathy was classified (0, 1, 2, 3, 4) and the activity of neovascularization was graded (0, 1, 2, 3, 4) by the surgeon intraoperatively. Samples of the vitreous were collected during surgery, and the activity of NF-κB and HIF-1α transcription factors and the expression levels of IL-6 and IL-8 were measured. The majority of samples fell into the retinopathy class 3 (n = 12) or 4 (n = 13). The level of IL-6 increased from 68.9 ± 46.8 pg/ml to 102.7 ± 94.1 pg/ml, and IL-8 increased from 165.1 ± 136.0 pg/ml to 521.0 ± 870.9 pg/ml (mean ± S.D., nonsignificant change: normality test followed with Mann-Whitney Rank Sum Test). According to the neovascularization activity, the samples fell into grade 1 (n = 7), 2 (n = 12) or 3 (n = 7). In IL-6, there was a statistically significant increase (P < .05) from grade 2 to 3: 58.6 ± 40.3 pg/ml and 158.4 ± 102.5 pg/ml, respectively (Kruskal-Wallis One-Way Analysis of Variance on Ranks followed with Dunn's Method). The level of IL-8 was as follows: in grade 1: 118.0 ± 62.4 pg/ml, in grade 2: 192.3 ± 127.1 pg/ml and in grade 3: 884.3 ± 1161.0 pg/ml (statistically nonsignificant change). There was a statistically significant linear regression between IL-6 and IL-8 (P < .001): IL-6 = 51.88 pg/ml + (0.092*IL-8), r = 0.772. Increased activity of the NF-κB and HIF-1α transcription factors was not observed. Interleukin-6 is a candidate to indicate activity of neovascularization process in PDR. It might be a new molecular therapeutic target to regulate innate immunity response in vitreous. Copyright © 2011 Elsevier Inc. All rights reserved.
Tian, Hanqin; Lu, Chaoqun; Yang, Jia; Banger, Kamaljit; Huntzinger, Deborah N; Schwalm, Christopher R; Michalak, Anna M; Cook, Robert; Ciais, Philippe; Hayes, Daniel; Huang, Maoyi; Ito, Akihiko; Jain, Atul K; Lei, Huimin; Mao, Jiafu; Pan, Shufen; Post, Wilfred M; Peng, Shushi; Poulter, Benjamin; Ren, Wei; Ricciuto, Daniel; Schaefer, Kevin; Shi, Xiaoying; Tao, Bo; Wang, Weile; Wei, Yaxing; Yang, Qichun; Zhang, Bowen; Zeng, Ning
2015-06-01
Soil is the largest organic carbon (C) pool of terrestrial ecosystems, and C loss from soil accounts for a large proportion of land-atmosphere C exchange. Therefore, a small change in soil organic C (SOC) can affect atmospheric carbon dioxide (CO 2 ) concentration and climate change. In the past decades, a wide variety of studies have been conducted to quantify global SOC stocks and soil C exchange with the atmosphere through site measurements, inventories, and empirical/process-based modeling. However, these estimates are highly uncertain, and identifying major driving forces controlling soil C dynamics remains a key research challenge. This study has compiled century-long (1901-2010) estimates of SOC storage and heterotrophic respiration (Rh) from 10 terrestrial biosphere models (TBMs) in the Multi-scale Synthesis and Terrestrial Model Intercomparison Project and two observation-based data sets. The 10 TBM ensemble shows that global SOC estimate ranges from 425 to 2111 Pg C (1 Pg = 10 15 g) with a median value of 1158 Pg C in 2010. The models estimate a broad range of Rh from 35 to 69 Pg C yr -1 with a median value of 51 Pg C yr -1 during 2001-2010. The largest uncertainty in SOC stocks exists in the 40-65°N latitude whereas the largest cross-model divergence in Rh are in the tropics. The modeled SOC change during 1901-2010 ranges from -70 Pg C to 86 Pg C, but in some models the SOC change has a different sign from the change of total C stock, implying very different contribution of vegetation and soil pools in determining the terrestrial C budget among models. The model ensemble-estimated mean residence time of SOC shows a reduction of 3.4 years over the past century, which accelerate C cycling through the land biosphere. All the models agreed that climate and land use changes decreased SOC stocks, while elevated atmospheric CO 2 and nitrogen deposition over intact ecosystems increased SOC stocks-even though the responses varied significantly among models. Model representations of temperature and moisture sensitivity, nutrient limitation, and land use partially explain the divergent estimates of global SOC stocks and soil C fluxes in this study. In addition, a major source of systematic error in model estimations relates to nonmodeled SOC storage in wetlands and peatlands, as well as to old C storage in deep soil layers.
NASA Astrophysics Data System (ADS)
Bala, G.; N, D.
2015-12-01
In this work, using the fully coupled NCAR Community Earth System Model (CESM1.0.4), we investigate the relative importance of CO2-fertilization, climate warming, anthropogenic nitrogen deposition, and land use and land cover change (LULCC) for terrestrial carbon uptake during the historical period (1850-2005). In our simulations, between the beginning and end of this period, we find an increase in global net primary productivity (NPP) on land of about 4 PgCyr-1 (8.1%) with a contribution of 2.3 PgCyr-1 from CO2-fertilization and 2.0 PgCyr-1 from nitrogen deposition. Climate warming also causes NPP to increase by 0.35 PgCyr-1 but LULCC causes a decline of 0.7 PgCyr-1. These results indicate that the recent increase in vegetation productivity is most likely driven by CO2 fertilization and nitrogen deposition. Further, we find that this configuration of CESM projects that the global terrestrial ecosystem has been a net source of carbon during 1850-2005 (release of 45.1±2.4 PgC), largely driven by historical LULCC related CO2 fluxes to the atmosphere. During the recent three decades (early 1970s to early 2000s), however, our model simulations project that the terrestrial ecosystem acts as a sink, taking up about 10 PgC mainly due to CO2 fertilization and nitrogen deposition. Our results are in good qualitative agreement with recent studies that indicate an increase in vegetation production and water use efficiency in the satellite era and that the terrestrial ecosystem has been a net sink for carbon in recent decades.
QuadBase2: web server for multiplexed guanine quadruplex mining and visualization
Dhapola, Parashar; Chowdhury, Shantanu
2016-01-01
DNA guanine quadruplexes or G4s are non-canonical DNA secondary structures which affect genomic processes like replication, transcription and recombination. G4s are computationally identified by specific nucleotide motifs which are also called putative G4 (PG4) motifs. Despite the general relevance of these structures, there is currently no tool available that can allow batch queries and genome-wide analysis of these motifs in a user-friendly interface. QuadBase2 (quadbase.igib.res.in) presents a completely reinvented web server version of previously published QuadBase database. QuadBase2 enables users to mine PG4 motifs in up to 178 eukaryotes through the EuQuad module. This module interfaces with Ensembl Compara database, to allow users mine PG4 motifs in the orthologues of genes of interest across eukaryotes. PG4 motifs can be mined across genes and their promoter sequences in 1719 prokaryotes through ProQuad module. This module includes a feature that allows genome-wide mining of PG4 motifs and their visualization as circular histograms. TetraplexFinder, the module for mining PG4 motifs in user-provided sequences is now capable of handling up to 20 MB of data. QuadBase2 is a comprehensive PG4 motif mining tool that further expands the configurations and algorithms for mining PG4 motifs in a user-friendly way. PMID:27185890
Transport and fate of hexachlorocyclohexanes in the oceanic air and surface seawater
NASA Astrophysics Data System (ADS)
Xie, Z.; Koch, B. P.; Möller, A.; Sturm, R.; Ebinghaus, R.
2011-09-01
Hexachlorocyclohexanes (HCHs) are ubiquitous organic pollutants derived from pesticide application. They are subject to long-range transport, persistent in the environment, and capable of accumulation in biota. Shipboard measurements of HCH isomers (α-, γ- and β-HCH) in surface seawater and boundary layer atmospheric samples were conducted in the Atlantic and the Southern Ocean in October to December of 2008. ΣHCHs concentrations (the sum of α-, γ- and β-HCH) in the lower atmosphere ranged from 12 to 37 pg m-3 (mean: 27 ± 11 pg m-3) in the Northern Hemisphere (NH), and from 1.5 to 4.0 pg m-3 (mean: 2.8 ± 1.1 pg m-3) in the Southern Hemisphere (SH), respectively. Water concentrations were: α-HCH 0.33-47 pg l-1, γ-HCH 0.02-33 pg l-1 and β-HCH 0.11-9.5 pg l-1. Dissolved HCH concentrations decreased from the North Atlantic to the Southern Ocean, indicating historical use of HCHs in the NH. Spatial distribution showed increasing concentrations from the equator towards North and South latitudes illustrating the concept of cold trapping in high latitudes and less interhemispheric mixing process. In comparison to concentrations measured in 1987-1999/2000, gaseous HCHs were slightly lower, while dissolved HCHs decreased by factor of 2-3 orders of magnitude. Air-water exchange gradients suggested net deposition for α-HCH (mean: 3800 pg m-2 day-1) and γ-HCH (mean: 2000 pg m-2 day-1), whereas β-HCH varied between equilibrium (volatilization: <0-12 pg m-2 day-1) and net deposition (range: 6-690 pg m-2 day-1). Climate change may significantly accelerate the release of "old" HCHs from continental storage (e.g. soil, vegetation and high mountains) and drive long-range transport from sources to deposition in the open oceans. Biological productivities may interfere with the air-water exchange process as well. Consequently, further investigation is necessary to elucidate the long term trends and the biogeochemical turnover of HCHs in the oceanic environment.
Winterhoff, Boris; Freyer, Luisa; Hammond, Edward; Giri, Shailendra; Mondal, Susmita; Roy, Debarshi; Teoman, Attila; Mullany, Sally A; Hoffmann, Robert; von Bismarck, Antonia; Chien, Jeremy; Block, Matthew S; Millward, Michael; Bampton, Darryn; Dredge, Keith; Shridhar, Viji
2015-05-01
Despite the utility of antiangiogenic drugs in ovarian cancer, efficacy remains limited due to resistance linked to alternate angiogenic pathways and metastasis. Therefore, we investigated PG545, an anti-angiogenic and anti-metastatic agent which is currently in Phase I clinical trials, using preclinical models of ovarian cancer. PG545's anti-cancer activity was investigated in vitro and in vivo as a single agent, and in combination with paclitaxel, cisplatin or carboplatin using various ovarian cancer cell lines and tumour models. PG545, alone, or in combination with chemotherapeutics, inhibited proliferation of ovarian cancer cells, demonstrating synergy with paclitaxel in A2780 cells. PG545 inhibited growth factor-mediated cell migration and reduced HB-EGF-induced phosphorylation of ERK, AKT and EGFR in vitro and significantly reduced tumour burden which was enhanced when combined with paclitaxel in an A2780 model or carboplatin in a SKOV-3 model. Moreover, in the immunocompetent ID8 model, PG545 also significantly reduced ascites in vivo. In the A2780 maintenance model, PG545 initiated with, and following paclitaxel and cisplatin treatment, significantly improved overall survival. PG545 increased plasma VEGF levels (and other targets) in preclinical models and in a small cohort of advanced cancer patients which might represent a potential biomarker of response. Our results support clinical testing of PG545, particularly in combination with paclitaxel, as a novel therapeutic strategy for ovarian cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.
Laube, Beth L; Afshar-Mohajer, Nima; Koehler, Kirsten; Chen, Gang; Lazarus, Philip; Collaco, Joseph M; McGrath-Morrow, Sharon A
2017-04-01
To determine the effect of an acute (1 week) and chronic (3 weeks) exposure to E-cigarette (E-cig) emissions on mucociliary clearance (MCC) in murine lungs. C57BL/6 male mice (age 10.5 ± 2.4 weeks) were exposed for 20 min/day to E-cigarette aerosol generated by a Joyetech 510-T ® E-cig containing either 0% nicotine (N)/propylene glycol (PG) for 1 week (n = 6), or 3 weeks (n = 9), or 2.4% N/PG for one week (n = 6), or 3 weeks (n = 9), followed by measurement of MCC. Control mice (n = 15) were not exposed to PG alone, or N/PG. MCC was assessed by gamma camera following aspiration of 99m technetium aerosol and was expressed as the amount of radioactivity removed from both lungs over 6 hours (MCC6hrs). Venous blood was assayed for cotinine levels in control mice and in mice exposed for 3-weeks to PG alone and N/PG. MCC6hrs in control mice and in mice acutely exposed to PG alone and N/PG was similar, averaging (±1 standard deviation) 8.6 ± 5.2%, 7.5 ± 2.8% and 11.2 ± 5.9%, respectively. In contrast, chronic exposure to PG alone stimulated MCC6hrs (17.2 ± 8.0)% and this stimulation was significantly blunted following chronic exposure to N/PG (8.7 ± 4.6)% (p < .05). Serum cotinine levels were <0.5 ng/ml in control mice and in mice exposed to PG alone, whereas, N/PG exposed mice averaged 14.6 ± 12.0 ng/ml. In this murine model, a chronic, daily, 20 min-exposure to N/PG, but not an acute exposure, slowed MCC, compared to exposure to PG alone and led to systemic absorption of nicotine.
Molecular imaging assessment of periodontitis lesions in an experimental mouse model.
Ideguchi, Hidetaka; Yamashiro, Keisuke; Yamamoto, Tadashi; Shimoe, Masayuki; Hongo, Shoichi; Kochi, Shinsuke; Yoshihara-Hirata, Chiaki; Aoyagi, Hiroaki; Kawamura, Mari; Takashiba, Shogo
2018-06-06
We aimed to evaluate molecular imaging as a novel diagnostic tool for mice periodontitis model induced by ligature and Porphyromonas gingivalis (Pg) inoculation. Twelve female mice were assigned to the following groups: no treatment as control group (n = 4); periodontitis group induced by ligature and Pg as Pg group (n = 4); and Pg group treated with glycyrrhizinic acid (GA) as Pg + GA group (n = 4). All mice were administered a myeloperoxidase (MPO) activity-specific luminescent probe and observed using a charge-coupled device camera on day 14. Image analysis on all mice was conducted using software to determine the signal intensity of inflammation. Additionally, histological and radiographic evaluation for periodontal inflammation and bone resorption at the site of periodontitis, and quantitative enzyme-linked immunosorbent assay (ELISA) were conducted on three mice for each group. Each experiment was performed three times. Levels of serum IgG antibody against P. gingivalis were significantly higher in the Pg than in the Pg + GA group. Histological analyses indicated that the number of osteoclasts and neutrophils were significantly lower in the Pg + GA than in the Pg group. Micro-CT image analysis indicated no difference in bone resorption between the Pg and Pg + GA groups. The signal intensity of MPO activity was detected on the complete craniofacial image; moreover, strong signal intensity was localized specifically at the periodontitis site in the ex vivo palate, with group-wise differences. Molecular imaging analysis based on MPO activity showed high sensitivity of detection of periodontal inflammation in mice. Molecular imaging analysis based on MPO activity has potential as a diagnostic tool for periodontitis.
NASA Astrophysics Data System (ADS)
Ju, W.; Chen, J.; Liu, R.; Liu, Y.
2013-12-01
The process-based Boreal Ecosystem Productivity Simulator (BEPS) model was employed in conjunction with spatially distributed leaf area index (LAI), land cover, soil, and climate data to simulate the carbon budget of global terrestrial ecosystems during the period from 1981 to 2008. The BEPS model was first calibrated and validated using gross primary productivity (GPP), net primary productivity (NPP), and net ecosystem productivity (NEP) measured in different ecosystems across the word. Then, four global simulations were conducted at daily time steps and a spatial resolution of 8 km to quantify the global terrestrial carbon budget and to identify the relative contributions of changes in climate, atmospheric CO2 concentration, and LAI to the global terrestrial carbon sink. The long term LAI data used to drive the model was generated through fusing Moderate Resolution Imaging Spectroradiometer (MODIS) and historical Advanced Very High Resolution Radiometer (AVHRR) data pixel by pixel. The meteorological fields were interpolated from the 0.5° global daily meteorological dataset produced by the land surface hydrological research group at Princeton University. The results show that the BEPS model was able to simulate carbon fluxes in different ecosystems. Simulated GPP, NPP, and NEP values and their temporal trends exhibited distinguishable spatial patterns. During the period from 1981 to 2008, global terrestrial ecosystems acted as a carbon sink. The averaged global totals of GPP NPP, and NEP were 122.70 Pg C yr-1, 56.89 Pg C yr-1, and 2.76 Pg C yr-1, respectively. The global totals of GPP and NPP increased greatly, at rates of 0.43 Pg C yr-2 (R2=0.728) and 0.26 Pg C yr-2 (R2=0.709), respectively. Global total NEP did not show an apparent increasing trend (R2= 0.036), averaged 2.26 Pg C yr-1, 3.21 Pg C yr-1, and 2.72 Pg C yr-1 for the periods from 1981 to 1989, from 1990 to 1999, and from 2000 to 2008, respectively. The magnitude and temporal trend of global terrestrial carbon budget were similar to the values recently reported by the Global Carbon Project. The obvious increases in global GPP and NPP were mainly driven by the enhancement of atmospheric CO2 fertilization. The change of LAI played the secondary role. Climate had a small negative impact on global terrestrial carbon sequestration. The relative importance of changes in climate, atmospheric CO2 concentration, and LAI in altering the temporal trend of carbon sequestration differed spatially. During the period from 2000 to 2008, terrestrial carbon sinks mainly existed in the northern region of South America, the western region of middle Africa, Southeast Asia, Southeast China, Southeast United States, and some regions of Eurasia.
PSF reconstruction for Compton-based prompt gamma imaging
NASA Astrophysics Data System (ADS)
Jan, Meei-Ling; Lee, Ming-Wei; Huang, Hsuan-Ming
2018-02-01
Compton-based prompt gamma (PG) imaging has been proposed for in vivo range verification in proton therapy. However, several factors degrade the image quality of PG images, some of which are due to inherent properties of a Compton camera such as spatial resolution and energy resolution. Moreover, Compton-based PG imaging has a spatially variant resolution loss. In this study, we investigate the performance of the list-mode ordered subset expectation maximization algorithm with a shift-variant point spread function (LM-OSEM-SV-PSF) model. We also evaluate how well the PG images reconstructed using an SV-PSF model reproduce the distal falloff of the proton beam. The SV-PSF parameters were estimated from simulation data of point sources at various positions. Simulated PGs were produced in a water phantom irradiated with a proton beam. Compared to the LM-OSEM algorithm, the LM-OSEM-SV-PSF algorithm improved the quality of the reconstructed PG images and the estimation of PG falloff positions. In addition, the 4.44 and 5.25 MeV PG emissions can be accurately reconstructed using the LM-OSEM-SV-PSF algorithm. However, for the 2.31 and 6.13 MeV PG emissions, the LM-OSEM-SV-PSF reconstruction provides limited improvement. We also found that the LM-OSEM algorithm followed by a shift-variant Richardson-Lucy deconvolution could reconstruct images with quality visually similar to the LM-OSEM-SV-PSF-reconstructed images, while requiring shorter computation time.
Rodríguez-Gacio, María del Carmen; Nicolás, Carlos; Matilla, Angel J
2004-02-01
During zygotic embryogenesis of turnip-tops (Brassica rapa L. cv. Rapa), the polygalacturonase activity (PG; EC 3.2.1.15), measured as a decrease in viscosity of polygalacturonic acid, reached a high when the desiccation process in the seeded silique was triggered and the valves had lost more than 70-75% of their moisture (45-50 DPA). The PG activity was not detected in any phases of developing seeds. This work also characterizes a cDNA with an open reading frame of 1303 bp and that codes for a putative PG called BrPG1. This falls into the category of clade-B, which includes PG related to shattering and abscission processes. The deduced BrPG1 sequence predicted a 434-residue-long precursor protein (46.7kDa) with a transit peptide sequence 23 amino acids long. A molecular mass of 44.3 kDa was calculated for the mature form of BrPG1, which showed high sequence similarity to PGA1 (97%) of B. napus (X98373) and ADPG1 (87%) of Arabidopsis thaliana (AJ002532). All conserved amino acids at the catalytic site of PGs belonging to clade-B were preserved on BrPG1. This BrPG1 gene was specifically expressed in the silique valves of turnip-tops and was temporally expressed at the beginning of its desiccation.
Impact of local environmental conditions on atmospheric electrical potential gradient measurements
NASA Astrophysics Data System (ADS)
Buzás, Attila; Barta, Veronika; Steinbach, Péter; Bór, József
2017-04-01
The atmospheric electrical potential gradient (PG) is a fundamental parameter of the global electric circuit (GEC) which comprises all large scale quasi-static electrical processes occurring in between the surface of the Earth and the lower ionosphere. The observation of PG near the Earth's surface plays a pivotal role in surveying our atmospheric electrical environment. The PG shows high variability in different temporal and spatial scales and it is especially sensitive to local effects. Therefore, obtaining a PG value which represents the general state of the GEC over a larger area rather than various effects due to measuring site-specific local factors is a challenging task. PG measurements are going on in the Széchenyi István Geophysical Observatory (NCK, 47°38' N, 16°43' E) of the Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences near Nagycenk, Hungary since 1961. PG sensors are set up in NCK in an open area surrounded by buildings and trees within 20 m distance. The effect of the changing vegetation on the long-term trend observed in the PG variation at NCK has been subject of debates [1,2,3]. In order to examine the possible bias in the measured PG values due to the relatively close buildings and trees at NCK, two sets of simultaneous PG measurements from two EFM-100 field mills were compared. One field mill was kept at a fixed location while the other was moved to grid points covering the open area around the fixed field mill. The measurement was done in fair weather conditions in summer and was repeated during the winter. The poster demonstrates the performance of this method in surveying the effect of various objects and the state of vegetation on the measured PG values by comparing the measured PG differences to those obtained from electrostatic models calculated by the finite element method using the FEMM 4.2 software package. [1] F. Märcz and R. G. Harrison, 2003, Annales Gephysicae, 21: 2193-2200 [2] F. Märcz and R. G. Harrison, 2005, Annales Gephysicae, 23: 1987-1995 [3] E. Williams, R. Markson and S. Heckman, 2005, Geophysical Research Letters, vol. 32
DNA accumulation on ventilation system filters in university buildings in Singapore
Luhung, Irvan; Wu, Yan; Xu, Siyu; Yamamoto, Naomichi; Nazaroff, William W.
2017-01-01
Introduction Biological particles deposit on air handling system filters as they process air. This study reports and interprets abundance and diversity information regarding biomass accumulation on ordinarily used filters acquired from several locations in a university environment. Methods DNA-based analysis was applied both to quantify (via DNA fluorometry and qPCR) and to characterize (via high-throughput sequencing) the microbial material on filters, which mainly processed recirculated indoor air. Results were interpreted in relation to building occupancy and ventilation system operational parameters. Results Based on accumulated biomass, average DNA concentrations per AHU filter surface area across nine indoor locations after twelve weeks of filter use were in the respective ranges 1.1 to 41 ng per cm2 for total DNA, 0.02 to 3.3 ng per cm2 for bacterial DNA and 0.2 to 2.0 ng DNA per cm2 for fungal DNA. The most abundant genera detected on the AHU filter samples were Clostridium, Streptophyta, Bacillus, Acinetobacter and Ktedonobacter for bacteria and Aspergillus, Cladosporium, Nigrospora, Rigidoporus and Lentinus for fungi. Conditional indoor airborne DNA concentrations (median (range)) were estimated to be 13 (2.6–107) pg/m3 for total DNA, 0.4 (0.05–8.4) pg/m3 for bacterial DNA and 2.3 (1.0–5.1) pg/m3 for fungal DNA. Conclusion Conditional airborne concentrations and the relative abundances of selected groups of genera correlate well with occupancy level. Bacterial DNA was found to be more responsive than fungal DNA to differences in occupancy level and indoor environmental conditions. PMID:29023520
NASA Astrophysics Data System (ADS)
Yamamoto, Yuhei; Tagami, Azusa; Shiarasaki, Toshihiro; Yonetani, Akira; Yamamoto, Takashi; Imai, Shoji
2018-04-01
The role of an Fe modifier on boron atomization process using graphite furnace-atomic absorbance spectrometry was investigated using a spectroscopic approach. The initial state of the Fe modifier in a pyrolytic graphite (PG) furnace was trivalent. With an increase in pyrolysis temperature, the Fe modifier was reduced in a stepwise manner. Fe2O3 and Fe3O4 were dominant at pyrolysis temperatures below 1300 K. From 1300 to 1500 K, FeO was dominant. At temperatures higher than 1700 K, Fe metal was dominant. After a drying step, 17.7% of the initial B remained in the PG furnace. After the pyrolysis step at 773 K, the residual fraction of B was similar to that after the drying step. After the pyrolysis step at a temperature of 1073 K, the residual fraction was 11.7%. At pyrolysis temperatures > 1738 K, the residual fraction was <3.3% (
Antioxidants Inhibit Formation of 3-Monochloropropane-1,2-diol Esters in Model Reactions.
Li, Chang; Jia, Hanbing; Shen, Mingyue; Wang, Yuting; Nie, Shaoping; Chen, Yi; Zhou, Yongqiang; Wang, Yuanxing; Xie, Mingyong
2015-11-11
The capacities of six antioxidants to inhibit the formation of 3-monochloropropane-1,2 diol (3-MCPD) esters were examined in this study. Inhibitory capacities of the antioxidants were investigated both in chemical models containing the precursors (tripalmitoyl glycerol, 1,2-dipalmitoyl-sn-glycerol, monopalmitoyl glycerol, and sodium chloride) of 3-MCPD esters and in oil models (rapeseed oil and sodium chloride). Six antioxidants, butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), tert-butyl hydroquinone (TBHQ), propyl gallate (PG), L-ascorbyl palmitate (AP), and α-tocopherol (VE), were found to exhibit inhibiting capacities on 3-MCPD ester formation both in chemical models and in oil models. TBHQ provided the highest inhibitory capacity both in chemical models and in oil models; 44% of 3-MCPD ester formation was inhibited in the presence of TBHQ (66 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min, followed by PG and AP. BHT, BHA, and VE appeared to have weaker inhibitory abilities in both models. VE exhibited the lowest inhibition rate; 22% of 3-MCPD esters were inhibited in the presence of VE (172 mg/kg of oil) after heating of rapeseed oil at 230 °C for 30 min. In addition, the inhibition rates of PG and VE decreased dramatically with an increase in temperature or heating time. The results suggested that some antioxidants, such as TBHQ, PG, and AP, could be the potential inhibitors of 3-MCPD esters in practice.
Zhang, Wanna; Liu, Bing; Lu, Yanhui; Liang, Gemei
2017-04-01
Salivary enzymes of many piercing-sucking insects lead to host plant injury. The salivary enzymes, polygalacturonase (PGs), act in insect feeding. PG family genes have been cloned from the mirid bug Apolygus lucorum, a pest of cotton and other host crops in China. We investigated the function of two PG genes that are highly expressed in A. lucorum nymphs (PG3-4) and adults (PG3-5), using siRNA injection-based RNA interference (RNAi). Accumulation of mRNA encoding both genes and their cognate proteins was significantly reduced (>60%) in experimental compared control green fluorescent protein (GFP) siRNA-treated mirids at 48 h post injection. Injury levels of cotton buds were also significantly reduced after injecting saliva isolated from PG3-4 and PG3-5 siRNA-treated A. lucorum. These results demonstrate that these two PG act in A. lucorum elicitation of plant injury. © 2017 Wiley Periodicals, Inc.
Morales-Ruán, María del Carmen; Shamah-Levy, Teresa; Amaya-Castellanos, Claudia Isabel; Salazar-Coronel, Araceli Apolonia; Jiménez-Aguilar, Alejandra; Amaya-Castellanos, Maritza Alejandra; Méndez-Gómez Humarán, Ignacio
2014-01-01
This study explored the intervention effect of the "Nutrition on the Go" strategy on the prevalence of overweight and obesity (OW+O), according to the role played by different patterns. Pattern Groups (PG) were determined based on schools' food availability and other variables at individual level: nutrition knowledge, physical activity, socioeconomic level and self-efficacy, using an ecological approach. The PG classification was achieved using Ward's cluster method. The prevalence of OW+O was higher in PGI (intermediate food availability and high socioeconomic index [SEI]) compared to PG 2 (high availability of food and lower SEI) and PG 3 (low availability of food and medium SEI) with a lower prevalence (p<0.00I). The PG-intervention interaction showed differences for PG 3 (p=0.066), the stage-PG interaction showed differences between PGs I and 3 (p=0.014) and between PGs 2 and 3 (p=0.055). Differences between PGs have important implications for the prevalence of OW+O.
Air-sea exchange fluxes of synthetic polycyclic musks in the North Sea and the Arctic.
Xie, Zhiyong; Ebinghaus, Ralf; Temme, Christian; Heemken, Olaf; Ruck, Wolfgang
2007-08-15
Synthetic polycyclic musk fragrances Galaxolide (HHCB) and Tonalide (AHTN) were measured simultaneously in air and seawater in the Arctic and the North Sea and in the rural air of northern Germany. Median concentrations of gas-phase HHCB and AHTN were 4 and 18 pg m(-3) in the Arctic, 28 and 18 pg m(-3) in the North Sea, and 71 and 21 pg m(-3) in northern Germany, respectively. Various ratios of HHCB/AHTN implied that HHCB is quickly removed by atmospheric degradation, while AHTN is relatively persistent in the atmosphere. Dissolved concentrations ranged from 12 to 2030 pg L(-1) for HHCB and from below the method detection limit (3 pg L(-1)) to 965 pg L(-1) for AHTN with median values of 59 and 23 pg L(-1), respectively. The medians of volatilization fluxes for HHCB and AHTN were 27.2 and 14.2 ng m(-2) day(-1) and the depositional fluxes were 5.9 and 3.3 ng m(-2) day(-1), respectively, indicating water-to-air volatilization is a significant process to eliminate HHCB and AHTN from the North Sea. In the Arctic, deposition fluxes dominated the air-sea gas exchange of HHCB and AHTN, suggesting atmospheric input controls the levels of HHCB and AHTN in the polar region.
Chen, M.; Zhuang, Q.; Cook, D. R.; ...
2011-09-21
Satellite remote sensing provides continuous temporal and spatial information of terrestrial ecosystems. Using these remote sensing data and eddy flux measurements and biogeochemical models, such as the Terrestrial Ecosystem Model (TEM), should provide a more adequate quantification of carbon dynamics of terrestrial ecosystems. Here we use Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI), Land Surface Water Index (LSWI) and carbon flux data of AmeriFlux to conduct such a study. First we modify the gross primary production (GPP) modeling in TEM by incorporating EVI and LSWI to account for the effects of the changes of canopy photosynthetic capacity, phenologymore » and water stress. Second, we parameterize and verify the new version of TEM with eddy flux data. We then apply the model to the conterminous United States over the period 2000–2005 at a 0.05° × 0.05° spatial resolution. We find that the new version of TEM made improvement over the previous version and generally captured the expected temporal and spatial patterns of regional carbon dynamics. We estimate that regional GPP is between 7.02 and 7.78 PgC yr -1 and net primary production (NPP) ranges from 3.81 to 4.38 Pg Cyr -1 and net ecosystem production (NEP) varies within 0.08– 0.73 PgC yr -1 over the period 2000–2005 for the conterminous United States. The uncertainty due to parameterization is 0.34, 0.65 and 0.18 PgC yr -1 for the regional estimates of GPP, NPP and NEP, respectively. The effects of extreme climate and disturbances such as severe drought in 2002 and destructive Hurricane Katrina in 2005 were captured by the model. Lastly, our study provides a new independent and more adequate measure of carbon fluxes for the conterminous United States, which will benefit studies of carbon-climate feedback and facilitate policy-making of carbon management and climate.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Min; Zhuang, Qianlai; Cook, David R.
2011-09-21
Satellite remote sensing provides continuous temporal and spatial information of terrestrial 24 ecosystems. Using these remote sensing data and eddy flux measurements and biogeochemical 25 models, such as the Terrestrial Ecosystem Model (TEM), should provide a more adequate 26 quantification of carbon dynamics of terrestrial ecosystems. Here we use Moderate Resolution 27 Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI), Land Surface Water Index 28 (LSWI) and carbon flux data of AmeriFlux to conduct such a study. We first modify the gross primary 29 production (GPP) modeling in TEM by incorporating EVI and LSWI to account for the effects of themore » 30 changes of canopy photosynthetic capacity, phenology and water stress. Second, we parameterize and 31 verify the new version of TEM with eddy flux data. We then apply the model to the conterminous 32 United States over the period 2000-2005 at a 0.05o ×0.05o spatial resolution. We find that the new 33 version of TEM generally captured the expected temporal and spatial patterns of regional carbon 34 dynamics. We estimate that regional GPP is between 7.02 and 7.78 Pg C yr-1 and net primary 35 production (NPP) ranges from 3.81 to 4.38 Pg C yr-1 and net ecosystem production (NEP) varies 36 within 0.08-0.73 Pg C yr-1 over the period 2000-2005 for the conterminous United States. The 37 uncertainty due to parameterization is 0.34, 0.65 and 0.18 Pg C yr-1 for the regional estimates of GPP, 38 NPP and NEP, respectively. The effects of extreme climate and disturbances such as severe drought in 39 2002 and destructive Hurricane Katrina in 2005 were captured by the model. Our study provides a 40 new independent and more adequate measure of carbon fluxes for the conterminous United States, 41 which will benefit studies of carbon-climate feedback and facilitate policy-making of carbon 42 management and climate.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, M.; Zhuang, Q.; Cook, D. R.
Satellite remote sensing provides continuous temporal and spatial information of terrestrial ecosystems. Using these remote sensing data and eddy flux measurements and biogeochemical models, such as the Terrestrial Ecosystem Model (TEM), should provide a more adequate quantification of carbon dynamics of terrestrial ecosystems. Here we use Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI), Land Surface Water Index (LSWI) and carbon flux data of AmeriFlux to conduct such a study. First we modify the gross primary production (GPP) modeling in TEM by incorporating EVI and LSWI to account for the effects of the changes of canopy photosynthetic capacity, phenologymore » and water stress. Second, we parameterize and verify the new version of TEM with eddy flux data. We then apply the model to the conterminous United States over the period 2000–2005 at a 0.05° × 0.05° spatial resolution. We find that the new version of TEM made improvement over the previous version and generally captured the expected temporal and spatial patterns of regional carbon dynamics. We estimate that regional GPP is between 7.02 and 7.78 PgC yr -1 and net primary production (NPP) ranges from 3.81 to 4.38 Pg Cyr -1 and net ecosystem production (NEP) varies within 0.08– 0.73 PgC yr -1 over the period 2000–2005 for the conterminous United States. The uncertainty due to parameterization is 0.34, 0.65 and 0.18 PgC yr -1 for the regional estimates of GPP, NPP and NEP, respectively. The effects of extreme climate and disturbances such as severe drought in 2002 and destructive Hurricane Katrina in 2005 were captured by the model. Lastly, our study provides a new independent and more adequate measure of carbon fluxes for the conterminous United States, which will benefit studies of carbon-climate feedback and facilitate policy-making of carbon management and climate.« less
NASA Astrophysics Data System (ADS)
Nine, Md J.; Kabiri, Shervin; Tung, Tran Thanh; Tran, Diana N. H.; Losic, Dusan
2018-05-01
The use of pristine graphene (pG) based on solution processed coating technologies is often limited by their poor dispersibility in water and organic solvents which prevents to achieve the best performing properties of pG in coating applications. To address these limitations, we developed a dispersant-free coating approach of pG based on their intrinsic solid-lubricity and interlayer electrostatic interactions. The "rotating drum" method was established to provide suitable conditions for electrostatic deposition of pG-powder which is demonstrated on two model substrates with granular and fibril morphologies (urea and acrylic fibers) to improve their physical and electrical properties. The results showed that the pG coating enables to minimize moisture induced caking tendency of commercial urea prills at a relative humidity (RH) of 85% (higher than critical humidity) exhibiting greater moisture rejection ability (∼2 times higher than uncoated urea) and to improve their anti-abrasive properties. The pG-powder coating applied on nonconductive acrylic fibers provides a stable conductive layer (∼0.8 ± 0.1 kΩ/sq) which made them suitable for using in wearable electronics, sensors and electromagnetic interference (EMI) shielding. The developed coating method for pG-powder based on "rotating drum" is generic, simple, eco-friendly, low-cost, and scalable for broad range of coating applications.
De Cock, Roosmarijn F W; Allegaert, Karel; Vanhaesebrouck, Sophie; de Hoon, Jan; Verbesselt, Rene; Danhof, Meindert; Knibbe, Catherijne A J
2014-06-01
Despite limited information being available on the pharmacokinetics of excipients, propylene glycol (PG) is often used as an excipient in both adults and children. The aim of this study is to characterize the renal and hepatic elimination of PG in preterm and term neonates. The pharmacokinetic analysis of PG was performed in NONMEM 6.2. on the basis of PG concentrations in plasma and/or urine samples for a total of 69 (pre)term neonates (birth weight 630-3980 g, gestational age 24-41 weeks, postnatal age 1-29 days) who received PG coadministered with intravenous paracetamol (5-10 mg/kg per 6 hours), phenobarbital (5 mg·kg(-1)·d(-1)), or both. To capture the time-dependent trend in the renal excretion of PG, different models based on time after the first dose, urine volume, and creatinine amount in urine were tested. A one-compartment model parameterized in terms of renal clearance, hepatic clearance, and volume of distribution was found to adequately describe the observations in both plasma and urine. After the first dose was administered, the renal elimination of PG was 15% of total clearance, which increased over time to 25% at 24 hours after the first dose of PG. This increase was best described using a hyperbolic function based on time after the first dose. Renal elimination of PG in (pre)term neonates is low, particularly compared with the reported percentage of 45% in adults, but it may increase with time after the first dose of PG. To study whether this increase is caused by an autoinduced increase in the renal secretion or a reduction of tubular reabsorption of PG, further research is needed.
On some methods for assessing earthquake predictions
NASA Astrophysics Data System (ADS)
Molchan, G.; Romashkova, L.; Peresan, A.
2017-09-01
A regional approach to the problem of assessing earthquake predictions inevitably faces a deficit of data. We point out some basic limits of assessment methods reported in the literature, considering the practical case of the performance of the CN pattern recognition method in the prediction of large Italian earthquakes. Along with the classical hypothesis testing, a new game approach, the so-called parimutuel gambling (PG) method, is examined. The PG, originally proposed for the evaluation of the probabilistic earthquake forecast, has been recently adapted for the case of 'alarm-based' CN prediction. The PG approach is a non-standard method; therefore it deserves careful examination and theoretical analysis. We show that the PG alarm-based version leads to an almost complete loss of information about predicted earthquakes (even for a large sample). As a result, any conclusions based on the alarm-based PG approach are not to be trusted. We also show that the original probabilistic PG approach does not necessarily identifies the genuine forecast correctly among competing seismicity rate models, even when applied to extensive data.
Sun, Bolu; Cai, Jinying; Li, Wuyan; Gou, Xiaodan; Gou, Yuqiang; Li, Dai; Hu, Fangdi
2018-07-15
In this study, a novel electrochemical immunosensor for early screening of depression markers-heat shock protein 70 (HSP70) was successfully developed based on the porous graphene (PG) with huge specific surface area and excellent structure. Benefiting from the strong adsorption and good bioactivity of PG which was initially prepared via a simple pyrolysis process, a variety of heat shock protein70 (HSP70) can be firmly loaded on the PG to construct the basic electrode (HSP70/PG/GCE),which was characterized by the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. Due to the HSP70 fixed on the surface of basic electrode and the HSP70 in the samples can competitively combine with the horseradish peroxidase labeled human HSP 70 antibody (HRP-Strept-Biotin-Ab). As a result, it presented a negative correlation between the concentration of HSP70 in samples and the detection signal of the proposed electrochemical immunosensor (HRP-Strept-Biotin-Ab-HSP70/PG/GCE) in the test liquid. The application of PG with excellent electrical conductivity in construction of immunosensor remarkably improved the sensitivity of the immunosensor for detection of HSP70. The proposed immunosensor demonstrated a wide linear range of 0.0448 ~ 100 ng/mL with a low detection limit of 0.02 ng/mL at 3σ. Moreover, the proposed immunosensor could be applied for the sensitive and efficient detection of HSP70 in real samples with good precision, acceptable stability, reproducibility and satisfactory results. Therefore, the HSP70 immunosensor provides a novel and convenient method for early clinical screening of depression markers-heat shock protein 70. Copyright © 2018 Elsevier B.V. All rights reserved.
Glyphosate catabolism by Pseudomonas sp
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shinabarger, D.L.
1986-01-01
The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing (3-/sup 14/C) glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO/sub 2/. Fractionation of stationary phase cells labeled with (3-/sup 14/C)glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling ofmore » PG2982 cells with (3-/sup 14/C)glyphosate revealed that (3-/sup 14/C)sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates.« less
Carlos A. Gonzalez-Benecke; Eric J. Jokela; Wendell P. Cropper; Rosvel Bracho; Daniel J. Leduc
2014-01-01
The forest simulation model, 3-PG, has been widely applied as a useful tool for predicting growth of forest species in many countries. The model has the capability to estimate the effects of management, climate and site characteristics on many stand attributes using easily available data. Currently, there is an increasing interest in estimating biomass and assessing...
Jose Luiz Stape; Michael G. Ryan; Dan Binkley
2004-01-01
The productivity of fast-growing tropical plantations depends, in part, on the ability of trees to obtain and utilize site resources, and the allocation of fixed carbon (C) to wood production. Simulation models can represent these processes and interactions, but the value of these models depends on their ability to improve predictions of stand growth relative to...
Spectral Analysis of PG 1034+001, the Exciting Star of Hewett 1
NASA Technical Reports Server (NTRS)
Kruk, J. W.; Mahsereci, M.; Ringat, E.; Rauch, T.; Werner, K.
2011-01-01
PG 1034+001 is an extremely hot, helium-rich DO-type star that excites the planetary nebula Hewett 1 and large parts of the surrounding interstellar medium. We present preliminary results of an ongoing spectral analysis by means of non-LTE model atmospheres that consider most elements from hydrogen to nickel. This analysis is based on high-resolution ultraviolet (FUSE, IUE) and optical (VLT/UVES, KECK) data. The results are compared with those of PG 1034+001's spectroscopic twin, the DO star PG 0038+ 199. Keywords. stars: abundances, stars: AGB and post-AGB, stars: atmospheres, stars: evolution, stars: individual (PG 1034+001, PG 0038+ 199), planetary nebulae: individual (Hewett 1)
Searching for frequency multiplets in the pulsating subdwarf B star PG 1219+534
NASA Astrophysics Data System (ADS)
Crooke, John; Roessler, Ryan; Reed, Michael
2017-01-01
Subdwarf B (sdB) stars represent the stripped cores of horizontal branch stars. Pulsating sdB stars allow us to probe this important stage in evolution. Thanks to Kepler data, we now know that sdB star rotation periods are long; on the order of tens of days. This explains why they were not measured using ground-based follow-up data, which typically only spanned a week or two. Azimuthal pulsation degeneracies are removed by rotation, and so by detected pulsation frequency multiplets, we can determine pulsation modes and apply constraints to models, which tell us stellar structure. We need the ground-based observations as Kepler did not detect many p-mode pulsators, but rather almost exclusively g-mode pulsators. The shorter-period p-modes occur in hotter sdB stars, and so we need these to measure the pulsation dependence across the horizontal branch. During 2015, we observed PG 1219+534 (hereafter PG1219) over several months using our local 16 inch robotic telescope. Here we report preliminary results of processing those data to search for pulsation multiplets.
Polyfluorinated compounds in ambient air from ship- and land-based measurements in northern Germany
NASA Astrophysics Data System (ADS)
Dreyer, Annekatrin; Ebinghaus, Ralf
Neutral volatile and semi-volatile polyfluorinated organic compounds (PFC) and ionic perfluorinated compounds were determined in air samples collected at two sites in the vicinity of Hamburg, Germany, and onboard the German research vessel Atair during a cruise in the German Bight, North Sea, in early November 2007. PUF/XAD-2/PUF cartridges and glass fiber filters as sampling media were applied to collect several fluorotelomer alcohols (FTOH), fluorotelomer acrylates (FTA), perfluoroalkyl sulfonamides (FASA), and perfluoroalkyl sulfonamido ethanols (FASE) in the gas- and particle-phase as well as a set of perfluorinated carboxylates (PFCA) and sulfonates (PFSA) in the particle-phase. This study presents the distribution of PFC in ambient air of the German North Sea and in the vicinity of Hamburg for the first time. Average total PFC concentrations in and around Hamburg (180 pg m -3) were higher than those observed in the German Bight (80 pg m -3). In the German Bight, minimum-maximum gas-phase concentrations of 17-82 pg m -3 for ΣFTOH, 2.6-10 pg m -3 for ΣFTA, 10-15 pg m -3 for ΣFASA, and 2-4.4 pg m -3 for ΣFASE were determined. In the vicinity of Hamburg, minimum-maximum gas-phase concentrations of 32-204 pg m -3 for ΣFTOH, 3-26 pg m -3 for ΣFTA, 3-18 pg m -3 for ΣFASA, and 2-15 pg m -3 for ΣFASE were detected. Concentrations of perfluorinated acids were in the range of 1-11 pg m -3. FTOH clearly dominated the substance spectrum; 8:2 FTOH occurred in maximum proportions. Air mass back trajectories, cluster, and correlation analyses revealed that the air mass origin and thus medium to long range atmospheric transport was the governing parameter for the amount of PFC in ambient air. Southwesterly located source regions seemed to be responsible for elevated PFC concentrations, local sources appeared to be of minor importance.
The simulated climate of the Last Glacial Maximum and insights into the global carbon cycle.
NASA Astrophysics Data System (ADS)
Buchanan, P. J.; Matear, R.; Lenton, A.; Phipps, S. J.; Chase, Z.; Etheridge, D. M.
2016-12-01
The ocean's ability to store large quantities of carbon, combined with the millennial longevity over which this reservoir is overturned, has implicated the ocean as a key driver of glacial-interglacial climates. However, the combination of processes that cause an accumulation of carbon within the ocean during glacial periods is still under debate. Here we present simulations of the Last Glacial Maximum (LGM) using the CSIRO Mk3L-COAL Earth System Model to test the contribution of key biogeochemical processes to ocean carbon storage. For the coupled LGM simulation, we find that significant cooling (3.2 °C), expanded minimum (Northern Hemisphere: 105 %; Southern Hemisphere: 225 %) and maximum (Northern Hemisphere: 145 %; Southern Hemisphere: 120 %) sea ice cover, and a reorganisation of the overturning circulation caused significant changes in ocean biogeochemical fields. The coupled LGM simulation stores an additional 322 Pg C in the deep ocean relative to the Pre-Industrial (PI) simulation. However, 839 Pg C is lost from the upper ocean via equilibration with a lower atmospheric CO2 concentration, causing a net loss of 517 Pg C relative to the PI simulation. The LGM deep ocean also experiences an oxygenation (>100 mmol O2 m-3) and deepening of the aragonite saturation depth (> 2,000 m deeper) at odds with proxy reconstructions. Hence, these physical changes cannot in isolation produce plausible biogeochemistry nor the required drawdown of atmospheric CO2 of 80-100 ppm at the LGM. With modifications to key biogeochemical processes, which include an increased export of organic matter due to a simulated release from iron limitation, a deepening of remineralisation and decreased inorganic carbon export driven by cooler temperatures, we find that the carbon content in the glacial oceanic reservoir can be increased (326 Pg C) to a level that is sufficient to explain the reduction in atmospheric and terrestrial carbon at the LGM (520 ± 400 Pg C). These modifications also go some way to reconcile simulated export production, aragonite saturation state and oxygen fields with those that have been reconstructed by proxy measurements, thereby implicating past changes in ocean biogeochemistry as an essential driver of the climate system.
Hugelius, Gustaf; Strauss, J.; Zubrzycki, S.; ...
2014-12-01
Soils and other unconsolidated deposits in the northern circumpolar permafrost region store large amounts of soil organic carbon (SOC). This SOC is potentially vulnerable to remobilization following soil warming and permafrost thaw, but SOC stock estimates were poorly constrained and quantitative error estimates were lacking. This study presents revised estimates of permafrost SOC stocks, including quantitative uncertainty estimates, in the 0–3 m depth range in soils as well as for sediments deeper than 3 m in deltaic deposits of major rivers and in the Yedoma region of Siberia and Alaska. Revised estimates are based on significantly larger databases compared tomore » previous studies. Despite this there is evidence of significant remaining regional data gaps. Estimates remain particularly poorly constrained for soils in the High Arctic region and physiographic regions with thin sedimentary overburden (mountains, highlands and plateaus) as well as for deposits below 3 m depth in deltas and the Yedoma region. While some components of the revised SOC stocks are similar in magnitude to those previously reported for this region, there are substantial differences in other components, including the fraction of perennially frozen SOC. Upscaled based on regional soil maps, estimated permafrost region SOC stocks are 217 ± 12 and 472 ± 27 Pg for the 0–0.3 and 0–1 m soil depths, respectively (±95% confidence intervals). Storage of SOC in 0–3 m of soils is estimated to 1035 ± 150 Pg. Of this, 34 ± 16 Pg C is stored in poorly developed soils of the High Arctic. Based on generalized calculations, storage of SOC below 3 m of surface soils in deltaic alluvium of major Arctic rivers is estimated as 91 ± 52 Pg. In the Yedoma region, estimated SOC stocks below 3 m depth are 181 ± 54 Pg, of which 74 ± 20 Pg is stored in intact Yedoma (late Pleistocene ice- and organic-rich silty sediments) with the remainder in refrozen thermokarst deposits. Total estimated SOC storage for the permafrost region is ∼1300 Pg with an uncertainty range of ∼1100 to 1500 Pg. Of this, ∼500 Pg is in non-permafrost soils, seasonally thawed in the active layer or in deeper taliks, while ∼800 Pg is perennially frozen. In conclusion, this represents a substantial ∼300 Pg lowering of the estimated perennially frozen SOC stock compared to previous estimates.« less
The distribution of soil phosphorus for global biogeochemical modeling
Yang, Xiaojuan; Post, Wilfred M.; Thornton, Peter E.; ...
2013-04-16
We discuss that phosphorus (P) is a major element required for biological activity in terrestrial ecosystems. Although the total P content in most soils can be large, only a small fraction is available or in an organic form for biological utilization because it is bound either in incompletely weathered mineral particles, adsorbed on mineral surfaces, or, over the time of soil formation, made unavailable by secondary mineral formation (occluded). In order to adequately represent phosphorus availability in global biogeochemistry–climate models, a representation of the amount and form of P in soils globally is required. We develop an approach that buildsmore » on existing knowledge of soil P processes and databases of parent material and soil P measurements to provide spatially explicit estimates of different forms of naturally occurring soil P on the global scale. We assembled data on the various forms of phosphorus in soils globally, chronosequence information, and several global spatial databases to develop a map of total soil P and the distribution among mineral bound, labile, organic, occluded, and secondary P forms in soils globally. The amount of P, to 50cm soil depth, in soil labile, organic, occluded, and secondary pools is 3.6 ± 3, 8.6 ± 6, 12.2 ± 8, and 3.2 ± 2 Pg P (Petagrams of P, 1 Pg = 1 × 10 15g) respectively. The amount in soil mineral particles to the same depth is estimated at 13.0 ± 8 Pg P for a global soil total of 40.6 ± 18 Pg P. The large uncertainty in our estimates reflects our limited understanding of the processes controlling soil P transformations during pedogenesis and a deficiency in the number of soil P measurements. In spite of the large uncertainty, the estimated global spatial variation and distribution of different soil P forms presented in this study will be useful for global biogeochemistry models that include P as a limiting element in biological production by providing initial estimates of the available soil P for plant uptake and microbial utilization.« less
Weck, Melanie N; Brenner, Hermann
2008-08-15
Helicobacter pylori is a major risk factor for chronic atrophic gastritis (CAG). A large variety of definitions of CAG have been used in epidemiologic studies in the past. The aim of this work was to systematically review and summarize estimates of the association between H. pylori infection and CAG according to the various definitions of CAG. Articles on the association between H. pylori infection and CAG published until July 2007 were identified. Separate meta-analyses were carried out for studies defining CAG based on gastroscopy with biopsy, serum pepsinogen I (PG I) only, the pepsinogen I/pepsinogen II ratio (PG I/PG II ratio) only, or a combination of PG I and the PG I/PG II ratio. Numbers of identified studies and summary odds ratios (OR) (95% confidence intervals) were as follows: gastroscopy with biopsy: n = 34, OR = 6.4 (4.0-10.1); PG I only: n = 13, OR = 0.9 (0.7-1.2); PG I/PG II ratio: n = 8, OR = 7.2 (3.1-16.8); combination of PG I and the PG I/PG II ratio: n = 20, OR = 5.7 (4.4-7.5). Studies with CAG definitions based on gastroscopy with biopsy or the PG I/PG II ratio (alone or in combination with PG I) yield similarly strong associations of H. pylori with CAG. The association is missed entirely in studies where CAG is defined by PG I only. (c) 2008 Wiley-Liss, Inc.
NASA Astrophysics Data System (ADS)
Jansson, Pär; Ferré, Benedicte
2017-04-01
Transport of methane in seawater occurs by diffusion and advection in the dissolved phase, and/or as free gas in form of bubbles. The fate of methane in bubbles emitted from the seafloor depends on both bubble size and ambient conditions. Larger bubbles can transport methane higher into the water column, potentially reaching the atmosphere and contributing to greenhouse gas concentrations and impacts. Single bubble or plume models have been used to predict the fate of bubble mediated methane gas emissions. Here, we present a new process based two-phase (free and dissolved) gas model in one dimension, which has the capability to dynamically couple water column properties such as temperature, salinity and dissolved gases with the free gas species contained in bubbles. The marine two-phase gas model in one dimension (M2PG1) uses a spectrum of bubbles and an Eulerian formulation, discretized on a finite-volume grid. It employs the most up-to-date equations for solubility and compressibility of the included gases, nitrogen, oxygen, carbon dioxide and methane. M2PG1 is an extension of PROBE (Omstedt, 2011), which facilitates atmospheric coupling and turbulence closures to realistically predict vertical mixing of all properties, including dissolved methane. This work presents the model's first application in an Arctic Ocean environment at the landward limit of the methane-hydrate stability zone west of Svalbard, where we observe substantial methane bubble release over longer time periods. The research is part of the Centre for Arctic Gas Hydrate, Environment and Climate (CAGE) and is supported by the Research Council of Norway through its Centres of Excellence funding scheme grant No. 223259 and UiT. Omstedt, A. (2011). Guide to process based modeling of lakes and coastal seas: Springer.
Holubova, Kristina; Nekovarova, Tereza; Pistovcakova, Jana; Sulcova, Alexandra; Stuchlík, Ales; Vales, Karel
2014-01-01
A number of studies demonstrated a rapid onset of an antidepressant effect of non-competitive N-methyl-d-aspartic acid receptor (NMDAR) antagonists. Nonetheless, its therapeutic potential is rather limited, due to a high coincidence of negative side-effects. Therefore, the challenge seems to be in the development of NMDAR antagonists displaying antidepressant properties, and at the same time maintaining regular physiological function of the NMDAR. Previous results demonstrated that naturally occurring neurosteroid 3α5β-pregnanolone sulfate shows pronounced inhibitory action by a use-dependent mechanism on the tonically active NMDAR. The aim of the present experiments is to find out whether the treatment with pregnanolone 3αC derivatives affects behavioral response to chronic and acute stress in an animal model of depression. Adult male mice were used throughout the study. Repeated social defeat and forced swimming tests were used as animal models of depression. The effect of the drugs on the locomotor/exploratory activity in the open-field test was also tested together with an effect on anxiety in the elevated plus maze. Results showed that pregnanolone glutamate (PG) did not induce hyperlocomotion, whereas both dizocilpine and ketamine significantly increased spontaneous locomotor activity in the open field. In the elevated plus maze, PG displayed anxiolytic-like properties. In forced swimming, PG prolonged time to the first floating. Acute treatment of PG disinhibited suppressed locomotor activity in the repeatedly defeated group-housed mice. Aggressive behavior of isolated mice was reduced after the chronic 30-day administration of PG. PG showed antidepressant-like and anxiolytic-like properties in the used tests, with minimal side-effects. Since PG combines GABAA receptor potentiation and use-dependent NMDAR inhibition, synthetic derivatives of neuroactive steroids present a promising strategy for the treatment of mood disorders. -3α5β-pregnanolone glutamate (PG) is a use-dependent antagonist of NMDA receptors.-We demonstrated that PG did not induce significant hyperlocomotion.-We showed that PG displayed anxiolytic-like and antidepressant-like properties.
Peach gum for efficient removal of methylene blue and methyl violet dyes from aqueous solution.
Zhou, Li; Huang, Jiachang; He, Benzhao; Zhang, Faai; Li, Huabin
2014-01-30
This study investigated the potential use of natural peach gum (PG) as alternative adsorbent for the removal of dyes from aqueous solutions. The PG showed high adsorption capacities and selectivity for cationic dyes (e.g., methylene blue (MB) and methyl violet (MV)) in the pH range 6-10. 98% of MB and MV could be adsorbed within 5 min, and both of the adsorptions reached equilibrium within 30 min. The dye uptake process followed the pseudo-second-order kinetic model. The intraparticle diffusion was not the sole rate controlling step. Equilibrium adsorption isotherm data indicated a good fit to the Langmuir isotherm model. Regeneration study revealed that PG could be well regenerated in acid solution. The recovered PG still exhibited high adsorption capacity even after five cycles of desorption-adsorption. On the basis of its excellent adsorption performance and facile availability, PG can be employed as an efficient low cost adsorbent for environmental cleanup. Copyright © 2013 Elsevier Ltd. All rights reserved.
Fire dynamics during the 20th century simulated by the Community Land Model
NASA Astrophysics Data System (ADS)
Kloster, S.; Mahowald, N. M.; Randerson, J. T.; Thornton, P. E.; Hoffman, F. M.; Levis, S.; Lawrence, P. J.; Feddema, J. J.; Oleson, K. W.; Lawrence, D. M.
2010-01-01
Fire is an integral Earth System process that interacts with climate in multiple ways. Here we assessed the parametrization of fires in the Community Land Model (CLM-CN) and improved the ability of the model to reproduce contemporary global patterns of burned areas and fire emissions. In addition to wildfires we extended CLM-CN to account for fires related to deforestation. We compared contemporary fire carbon emissions predicted by the model to satellite based estimates in terms of magnitude, spatial extent as well as interannual and seasonal variability. Longterm trends during the 20th century were compared with historical estimates. Overall we found the best agreement between simulation and observations for the fire parametrization based on the work by Arora and Boer (2005). We obtain substantial improvement when we explicitly considered human caused ignition and fire suppression as a function of population density. Simulated fire carbon emissions ranged between 2.0 and 2.4 Pg C/year for the period 1997-2004. Regionally the simulations had a low bias over Africa and a high bias over South America when compared to satellite based products. The net terrestrial carbon source due to land use change for the 1990s was 1.2 Pg C/year with 11% stemming from deforestation fires. During 2000-2004 this flux decreased to 0.85 Pg C/year with a similar relative contribution from deforestation fires. Between 1900 and 1960 we simulated a slight downward trend in global fire emissions, which is explained by reduced fuels as a consequence of wood harvesting and partly by increasing fire suppression. The model predicted an upward trend in the last three decades of the 20th century caused by climate variations and large burning events associated with ENSO induced drought conditions.
Fire dynamics during the 20th century simulated by the Community Land Model
NASA Astrophysics Data System (ADS)
Kloster, S.; Mahowald, N. M.; Randerson, J. T.; Thornton, P. E.; Hoffman, F. M.; Levis, S.; Lawrence, P. J.; Feddema, J. J.; Oleson, K. W.; Lawrence, D. M.
2010-06-01
Fire is an integral Earth System process that interacts with climate in multiple ways. Here we assessed the parametrization of fires in the Community Land Model (CLM-CN) and improved the ability of the model to reproduce contemporary global patterns of burned areas and fire emissions. In addition to wildfires we extended CLM-CN to account for fires related to deforestation. We compared contemporary fire carbon emissions predicted by the model to satellite-based estimates in terms of magnitude and spatial extent as well as interannual and seasonal variability. Long-term trends during the 20th century were compared with historical estimates. Overall we found the best agreement between simulation and observations for the fire parametrization based on the work by Arora and Boer (2005). We obtained substantial improvement when we explicitly considered human caused ignition and fire suppression as a function of population density. Simulated fire carbon emissions ranged between 2.0 and 2.4 Pg C/year for the period 1997-2004. Regionally the simulations had a low bias over Africa and a high bias over South America when compared to satellite-based products. The net terrestrial carbon source due to land use change for the 1990s was 1.2 Pg C/year with 11% stemming from deforestation fires. During 2000-2004 this flux decreased to 0.85 Pg C/year with a similar relative contribution from deforestation fires. Between 1900 and 1960 we predicted a slight downward trend in global fire emissions caused by reduced fuels as a consequence of wood harvesting and also by increases in fire suppression. The model predicted an upward trend during the last three decades of the 20th century as a result of climate variations and large burning events associated with ENSO-induced drought conditions.
Soil Carbon in North American, Arctic, and Boreal Regions
NASA Astrophysics Data System (ADS)
Lajtha, K.; Bailey, V. L.; Schuur, E.; McGuire, D.; Romanovsky, V. E.
2017-12-01
Globally, soils contain more than 3 times as much as C as the atmosphere and >4 times more C than the world's biota, therefore even small changes in soil C stocks could lead to large changes in the atmospheric concentration of CO2. Since SOCCR-1, improvements have been made in quantifying stocks and uncertainties in stocks of soil C to a depth of 1 m across North America. Estimates for soil carbon stocks in the US (CONUS + Alaska) range from 151 - 162 Pg C, based on extensive sampling and analysis. Estimates for Canada average about 262 Pg C, but sampling is not as extensive. Soil C for Mexico is calculated as 18 Pg C, but there is a great deal of uncertainty surrounding this value. These soil carbon stocks are sensitive to agricultural management, land use and land cover change, and development and loss of C-rich soils such as wetlands. Climate change is a significant threat although may be partially mitigated by increased plant production. Carbon stored in permafrost zone circumpolar soils is equal to 1330-1580 Pg C, almost twice that contained in the atmosphere and about order of magnitude greater than carbon contained in plant biomass, woody debris, and litter in the boreal and tundra biomes combined. Surface air temperature change is amplified in high latitude regions such that Arctic temperature rise is about 2.5 times faster than for the globe as a whole, and thus 5 - 15% of this carbon is considered vulnerable to release to the atmosphere by the year 2100 following the current trajectory of global and Arctic warming. This amount is likely to be up to an order of magnitude larger loss than the increase in carbon stored in plant biomass under the same changing conditions. Models of soil organic matter dynamics have been greatly improved in the last decade by including greater process-level understanding of factors that affect soil C stabilization and destabilization, yet structural features of many models are still limited in representing Arctic and boreal zone processes.
Climatic and biotic controls on annual carbon storage in Amazonian ecosystems
Tian, H.; Melillo, J.M.; Kicklighter, D.W.; McGuire, A.D.; Helfrich, J.; Moore, B.; Vorosmarty, C.J.
2000-01-01
1 The role of undisturbed tropical land ecosystems in the global carbon budget is not well understood. It has been suggested that inter-annual climate variability can affect the capacity of these ecosystems to store carbon in the short term. In this paper, we use a transient version of the Terrestrial Ecosystem Model (TEM) to estimate annual carbon storage in undisturbed Amazonian ecosystems during the period 1980-94, and to understand the underlying causes of the year-to-year variations in net carbon storage for this region. 2 We estimate that the total carbon storage in the undisturbed ecosystems of the Amazon Basin in 1980 was 127.6 Pg C, with about 94.3 Pg C in vegetation and 33.3 Pg C in the reactive pool of soil organic carbon. About 83% of the total carbon storage occurred in tropical evergreen forests. Based on our model's results, we estimate that, over the past 15 years, the total carbon storage has increased by 3.1 Pg C (+ 2%), with a 1.9-Pg C (+2%) increase in vegetation carbon and a 1.2-Pg C (+4%) increase in reactive soil organic carbon. The modelled results indicate that the largest relative changes in net carbon storage have occurred in tropical deciduous forests, but that the largest absolute changes in net carbon storage have occurred in the moist and wet forests of the Basin. 3 Our results show that the strength of interannual variations in net carbon storage of undisturbed ecosystems in the Amazon Basin varies from a carbon source of 0.2 Pg C/year to a carbon sink of 0.7 Pg C/year. Precipitation, especially the amount received during the drier months, appears to be a major controller of annual net carbon storage in the Amazon Basin. Our analysis indicates further that changes in precipitation combine with changes in temperature to affect net carbon storage through influencing soil moisture and nutrient availability. 4 On average, our results suggest that the undisturbed Amazonian ecosystems accumulated 0.2 Pg C/year as a result of climate variability and increasing atmospheric CO2 over the study period. This amount is large enough to have compensated for most of the carbon losses associated with tropical deforestation in the Amazon during the same period. 5 Comparisons with empirical data indicate that climate variability and CO2 fertilization explain most of the variation in net carbon storage for the undisturbed ecosystems. Our analyses suggest that assessment of the regional carbon budget in the tropics should be made over at least one cycle of El Nino-Southern Oscillation because of inter-annual climate variability. Our analyses also suggest that proper scaling of the site-specific and sub-annual measurements of carbon fluxes to produce Basin-wide flux estimates must take into account seasonal and spatial variations in net carbon storage.
Carbon pools in China’s terrestrial ecosystems: New estimates based on an intensive field survey
Tang, Xuli; Zhao, Xia; Bai, Yongfei; Wang, Wantong; Zhao, Yongcun; Wan, Hongwei; Xie, Zongqiang; Shi, Xuezheng; Wu, Bingfang; Wang, Gengxu; Yan, Junhua; Ma, Keping; Du, Sheng; Li, Shenggong; Han, Shijie; Ma, Youxin; Hu, Huifeng; Yang, Yuanhe; Han, Wenxuan; He, Hongling; Yu, Guirui; Fang, Jingyun; Zhou, Guoyi
2018-01-01
China’s terrestrial ecosystems have functioned as important carbon sinks. However, previous estimates of carbon budgets have included large uncertainties owing to the limitations of sample size, multiple data sources, and inconsistent methodologies. In this study, we conducted an intensive field campaign involving 14,371 field plots to investigate all sectors of carbon stocks in China’s forests, shrublands, grasslands, and croplands to better estimate the regional and national carbon pools and to explore the biogeographical patterns and potential drivers of these pools. The total carbon pool in these four ecosystems was 79.24 ± 2.42 Pg C, of which 82.9% was stored in soil (to a depth of 1 m), 16.5% in biomass, and 0.60% in litter. Forests, shrublands, grasslands, and croplands contained 30.83 ± 1.57 Pg C, 6.69 ± 0.32 Pg C, 25.40 ± 1.49 Pg C, and 16.32 ± 0.41 Pg C, respectively. When all terrestrial ecosystems are taken into account, the country’s total carbon pool is 89.27 ± 1.05 Pg C. The carbon density of the forests, shrublands, and grasslands exhibited a strong correlation with climate: it decreased with increasing temperature but increased with increasing precipitation. Our analysis also suggests a significant sequestration potential of 1.9–3.4 Pg C in forest biomass in the next 10–20 years assuming no removals, mainly because of forest growth. Our results update the estimates of carbon pools in China’s terrestrial ecosystems based on direct field measurements, and these estimates are essential to the validation and parameterization of carbon models in China and globally. PMID:29666314
Fierro, S; Viñoles, C; Olivera-Muzante, J
2016-04-01
To determine estrous, ovarian and reproductive responses after different prostaglandin (PG)-based protocols, ewes were assigned to groups PG10, PG12, PG14 or PG16 (twoPG injections administered 10, 12, 14 or 16 days apart; respectively). Experiment I (n=132) was conducted to evaluate the estrous response, ovulation rate (OR), conception and fertility. Experiment II (n=24) was conducted to evaluate ovarian follicle growth, steroid concentrations and the interval from the second PG injection to estrus (PG-estrus) and ovulation (PG-ovulation). Estrous response was less with the PG16 (P<0.05) treatment, and the extent of estrous synchrony was greater with the PG10 and PG12 treatments. Ovarian follicle growth and the intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups (P>0.05). From 8 to 4 days before estrus, progesterone (P4) concentrations were greater for the PG14 and PG16 than for the PG10 and PG12 (P<0.05) groups. There were more days where concentrations of P4 were above 3.18 nmol/L with the PG14 and PG16 than PG10 and PG12 (P<0.05) treatments. Use of the PG14 and PG16 treatments resulted in greater estradiol (E2) at estrus and 12h later than use of the PG10 and PG12 treatments. A positive correlation was observed between the duration of the luteal phase and maximum E2 concentrations, and between duration of the luteal phase and days with E2 concentrations above 10 pmol/L. Conception and fertility were greater with use of the PG14 compared with PG10 and PG12 (P<0.05) treatments. The administration of two PG injections 10, 12, 14 or 16 days apart resulted in different durations of the luteal phase that were positively associated with E2 concentrations and the reproductive outcome. The shorter luteal phases were associated with greater synchrony in time of estrus. The intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups. Copyright © 2016 Elsevier B.V. All rights reserved.
Geometric Image Biomarker Changes of the Parotid Gland Are Associated With Late Xerostomia.
van Dijk, Lisanne V; Brouwer, Charlotte L; van der Laan, Hans Paul; Burgerhof, Johannes G M; Langendijk, Johannes A; Steenbakkers, Roel J H M; Sijtsema, Nanna M
2017-12-01
To identify a surrogate marker for late xerostomia 12 months after radiation therapy (Xer 12m ), according to information obtained shortly after treatment. Differences in parotid gland (PG) were quantified in image biomarkers (ΔIBMs) before and 6 weeks after radiation therapy in 107 patients. By performing stepwise forward selection, ΔIBMs that were associated with Xer 12m were selected. Subsequently other variables, such as PG dose and acute xerostomia scores, were added to improve the prediction performance. All models were internally validated. Prediction of Xer 12m based on PG surface reduction (ΔPG-surface) was good (area under the receiver operating characteristic curve, 0.82). Parotid gland dose was related to ΔPG-surface (P<.001, R 2 = 0.27). The addition of acute xerostomia scores to the ΔPG-surface improved the prediction of Xer 12m significantly, and vice versa. The final model including ΔPG-surface and acute xerostomia had outstanding performance in predicting Xer 12m early after radiation therapy (area under the receiver operating characteristic curve, 0.90). Parotid gland surface reduction was associated with late xerostomia. The early posttreatment model with ΔPG-surface and acute xerostomia scores can be considered as a surrogate marker for late xerostomia. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
A fast process development flow by applying design technology co-optimization
NASA Astrophysics Data System (ADS)
Chen, Yi-Chieh; Yeh, Shin-Shing; Ou, Tsong-Hua; Lin, Hung-Yu; Mai, Yung-Ching; Lin, Lawrence; Lai, Jun-Cheng; Lai, Ya Chieh; Xu, Wei; Hurat, Philippe
2017-03-01
Beyond 40 nm technology node, the pattern weak points and hotspot types increase dramatically. The typical patterns for lithography verification suffers huge turn-around-time (TAT) to handle the design complexity. Therefore, in order to speed up process development and increase pattern variety, accurate design guideline and realistic design combinations are required. This paper presented a flow for creating a cell-based layout, a lite realistic design, to early identify problematic patterns which will negatively affect the yield. A new random layout generating method, Design Technology Co-Optimization Pattern Generator (DTCO-PG), is reported in this paper to create cell-based design. DTCO-PG also includes how to characterize the randomness and fuzziness, so that it is able to build up the machine learning scheme which model could be trained by previous results, and then it generates patterns never seen in a lite design. This methodology not only increases pattern diversity but also finds out potential hotspot preliminarily. This paper also demonstrates an integrated flow from DTCO pattern generation to layout modification. Optical Proximity Correction, OPC and lithographic simulation is then applied to DTCO-PG design database to detect hotspots and then hotspots or weak points can be automatically fixed through the procedure or handled manually. This flow benefits the process evolution to have a faster development cycle time, more complexity pattern design, higher probability to find out potential hotspots in early stage, and a more holistic yield ramping operation.
MitoQ modulates oxidative stress and decreases inflammation following hemorrhage.
Powell, Rebecca D; Swet, Jacob H; Kennedy, Kenneth L; Huynh, Toan T; Murphy, Michael P; Mckillop, Iain H; Evans, Susan L
2015-03-01
Oxidative stress associated with hemorrhagic shock and reperfusion (HSR) results in the production of superoxide radicals and other reactive oxygen species, leading to cell damage and multiple-organ dysfunction. We sought to determine if MitoQ, a mitochondria-targeted antioxidant, reduces morbidity in a rat model of HSR by limiting oxidative stress. HSR was achieved in male rats by arterial blood withdrawal to a mean arterial pressure of 25 ± 2 mm Hg for 1 hour before resuscitation. MitoQ (5 mg/kg), TPP (triphenylphosphonium, 5 mg/kg) or saline (0.9% vol./vol.) was administered intravenously 30 minutes before resuscitation, followed by an intraperitoneal administration (MitoQ, 20 mg/kg) immediately after resuscitation (n = 5 per group). Morbidity was assessed based on cumulative markers of animal distress (0-10 scale). Rats were sacrificed 2 hours after procedure completion, and liver tissue was collected and processed for histology or assayed for lipid peroxidation (thiobarbituric acid reactive substance [TBARS]) or endogenous antioxidant (catalase, glutathione peroxidase [GPx], and superoxide dismutase) activity. HSR significantly increased morbidity as well as TBARS and catalase activities versus sham. Conversely, no difference in GPx or superoxide dismutase activity was measured between sham, HSR, and TPP, MitoQ administration reduced morbidity versus HSR (5.8 ± 0.3 vs. 7.6 ± 0.3; p < 0.05), while TPP administration significantly reduced hepatic necrosis versus both HSR and HSR-MitoQ (1.2 ± 0.1 vs. 2.0 ± 0.2 vs. 1.9 ± 0.2; p < 0.05, n = 5). Analysis of oxidative stress demonstrated increased TBARS and GPx in HSR-MitoQ versus sham (12.0 ± 1.1 μM vs. 6.2 ± 0.5 μM and 37.9 ± 3.0 μmol/min/mL vs. 22.9 ± 2.7 μmol/min/mL, TBARS and GPx, respectively, n = 5; p < 0.05). Conversely, catalase activity in HSR-MitoQ was reduced versus HSR (1.96 ± 1.17 mol/min/mL vs. 2.58 ± 1.81 mol/min/mL; n = 5; p < 0.05). Finally, MitoQ treatment decreased tumor necrosis factor α (0.66 ± 0.07 pg/mL vs. 0.92 ± 0.08 pg/mL) and interleukin 6 (7.3 ± 0.8 pg/mL vs. 11 ± 0.9 pg/mL) versus HSR as did TPP alone (0.58 ± 0.05 pg/mL vs. 0.92 ± 0.08 pg/mL; 6.7 ± 0.6 pg/mL vs. 11 ± 0.9 pg/mL; n = 5; p < 0.05). Our data demonstrate that MitoQ treatment following hemorrhage significantly limits morbidity and decreases hepatic tumor necrosis factor α and interleukin 6. In addition, MitoQ differentially modulates oxidative stress and hepatic antioxidant activity.
Ozone and haze pollution weakens net primary productivity in China
NASA Astrophysics Data System (ADS)
Yue, Xu; Unger, Nadine; Harper, Kandice; Xia, Xiangao; Liao, Hong; Zhu, Tong; Xiao, Jingfeng; Feng, Zhaozhong; Li, Jing
2017-05-01
Atmospheric pollutants have both beneficial and detrimental effects on carbon uptake by land ecosystems. Surface ozone (O3) damages leaf photosynthesis by oxidizing plant cells, while aerosols promote carbon uptake by increasing diffuse radiation and exert additional influences through concomitant perturbations to meteorology and hydrology. China is currently the world's largest emitter of both carbon dioxide and short-lived air pollutants. The land ecosystems of China are estimated to provide a carbon sink, but it remains unclear whether air pollution acts to inhibit or promote carbon uptake. Here, we employ Earth system modeling and multiple measurement datasets to assess the separate and combined effects of anthropogenic O3 and aerosol pollution on net primary productivity (NPP) in China. In the present day, O3 reduces annual NPP by 0.6 Pg C (14 %) with a range from 0.4 Pg C (low O3 sensitivity) to 0.8 Pg C (high O3 sensitivity). In contrast, aerosol direct effects increase NPP by 0.2 Pg C (5 %) through the combination of diffuse radiation fertilization, reduced canopy temperatures, and reduced evaporation leading to higher soil moisture. Consequently, the net effects of O3 and aerosols decrease NPP by 0.4 Pg C (9 %) with a range from 0.2 Pg C (low O3 sensitivity) to 0.6 Pg C (high O3 sensitivity). However, precipitation inhibition from combined aerosol direct and indirect effects reduces annual NPP by 0.2 Pg C (4 %), leading to a net air pollution suppression of 0.8 Pg C (16 %) with a range from 0.6 Pg C (low O3 sensitivity) to 1.0 Pg C (high O3 sensitivity). Our results reveal strong dampening effects of air pollution on the land carbon uptake in China today. Following the current legislation emission scenario, this suppression will be further increased by the year 2030, mainly due to a continuing increase in surface O3. However, the maximum technically feasible reduction scenario could drastically relieve the current level of NPP damage by 70 % in 2030, offering protection of this critical ecosystem service and the mitigation of long-term global warming.
NASA Astrophysics Data System (ADS)
Tan, Zeli; Zhuang, Qianlai
2015-12-01
The importance of methane emissions from pan-Arctic lakes in the global carbon cycle has been suggested by recent studies. These studies indicated that climate change influences this methane source mainly in two ways: the warming of lake sediments and the evolution of thermokarst lakes. Few studies have been conducted to quantify the two impacts together in a unified modeling framework. Here we adapt a region-specific lake evolution model to the pan-Arctic scale and couple it with a lake methane biogeochemical model to quantify the change of this freshwater methane source in the 21st century. Our simulations show that the extent of thaw lakes will increase throughout the 21st century in the northern lowlands of the pan-Arctic where the reworking of epigenetic ice in drained lake basins will continue. The projected methane emissions by 2100 are 28.3 ± 4.5 Tg CH4 yr-1 under a low warming scenario (Representative Concentration Pathways (RCPs) 2.6) and 32.7 ± 5.2 Tg CH4 yr-1 under a high warming scenario (RCP 8.5), which are about 2.5 and 2.9 times the simulated present-day emissions. Most of the emitted methane originates from nonpermafrost carbon stock. For permafrost carbon, the methanogenesis will mineralize a cumulative amount of 3.4 ± 0.8 Pg C under RCP 2.6 and 3.9 ± 0.9 Pg C under RCP 8.5 from 2006 to 2099. The projected emissions could increase atmospheric methane concentrations by 55.0-69.3 ppb. This study further indicates that the warming of lake sediments dominates the increase of methane emissions from pan-Arctic lakes in the future.
Li, Tian-Fu; Wu, Qiu-Yue; Li, Wei-Wei; Zhang, Cui; Li, Na; Shang, Xue-Jun; Xia, Xin-Yi; Xu, Hao-Qin; Huang, Yu-Feng
2014-05-01
To evaluate the therapeutic effect of Compound Xuanju Capsule (CXC) on autoimmune prostatitis in rat models. Sixty healthy male Wistar rats were randomly divided into five groups of equal number: blank control, low-concentration purified prostate protein (low-conc PPP), low-conc PPP + CXC treatment, high-concentration PPP (hi-con PPP), and hi-conc PPP + CXC treatment. Autoimmune prostatitis models were established by intragastric administration of PPP solution at 15 mg/ml (low concentration) and 80 mg/ml, respectively. At 30 days after modeling, the rats in the blank control and low-conc and hi-conc PPP model groups were treated with normal saline, and those in the other two groups with CXC at a daily dose of 0.068 g/ml. At 30, 45, and 60 days, all the animals were sacrificed for observation of pathological changes in the prostate tissue and determination of the levels of IL-8, IL-10, and TNF-alpha in the serum. Compared with the PPP models, the hi-conc PPP + CXC group showed significantly reduced levels of IL-8 and TNF-alpha in the serum at 45 days ([148.54 +/- 17.23] and [62.14 +/- 5.59] pg/ml vs [100.77 +/- 11.08] and [32.63 +/- 2.91] pg/ml, P < 0.05) and at 60 days ([143.69 +/- 17.28] and [59.38 +/- 5.50] pg/mlvs [95.77 +/-10.53] and [29.63 +/- 2.66] pg/ml, P < 0.05), and so did the low-cone PPP + CXC group at 45 days ([128.47 +/- 12.21] and [40.43 +/- 3.64] pg/ml vs [111.76 +/- 10.07] and [35.44 +/- 3.17] pg/ml, P < 0.05) and at 60 days ([131.07 +/- 10.93] and [43.34 +/- 3.91] pg/ml vs [97.46 +/- 8.75] and [30.44 +/- 2.75] pg/ml, P < 0.05). The serum level of IL-10 was remarkably elevated in the hi-cone PPP + CXC group as compared with that of the PPP models at 45 and 60 days ([189.14 +/- 16.78] and [184.14 +/- 15.89] pg/ml vs [230.48 +/- 29.96] and [248.48 +/- 31.03] pg/ml, P < 0.05), and so was it in low-cone PPP + CXC group ([223.14 +/- 17.87] and [224.14 +/- 17.93] pg/ml vs [231.42 +/- 23.18] and [249.42 +/- 24.97] pg/ml, P < 0.05). Pathological examination revealed morphological damages to the prostate tissue and infiltration of inflammatory cells in the model rats, but no obvious changes in the normal controls. At 15 days of treatment, the rats in the PPP + CXC group showed enlarged prostate glandular cavity, mild proliferation of epithelial cells, no obvious infiltration of inflammatory cells in the interstitial tissue, and a few visible fibrous tissues under the light microscope. Compound Xuanju Capsule is efficacious on autoimmune prostatis in rats by reducing inflammatory changes in the prostate tissue and improving the expression of inflammatory factors.
Powell, Ann L T; Kalamaki, Mary S; Kurien, Philip A; Gurrieri, Sergio; Bennett, Alan B
2003-12-03
Tomatoes are grown for fresh consumption or for processing of the fruit. Some ripening-associated processes of the fruit can either contribute to or degrade attributes associated with both fresh and processing quality. For example, cell wall disassembly is associated with loss of fresh fruit firmness as well as with loss of processed tomato product viscosity. Several enzymes contribute to cell wall polysaccharide disassembly. Polygalacturonase (PG, poly[1,4-alpha-d-galactouronide] glucanohydrolase, EC 3.2.1.15) is among the most abundant polysaccharide hydrolases in ripening tomato fruit and is the major contributor to pectin depolymerization. Expansin (LeExp1) is also abundant in ripening fruit and is proposed to contribute to cell wall disassembly by nonhydrolytic activity, possibly by increasing substrate accessibility to other enzymes. Suppression of either LePG or LeExp1 expression alone results in altered softening and/or shelf life characteristics. To test whether simultaneous suppression of both LePG and LeExp1 expression influences fruit texture in additive or synergistic ways, transgenic Lycopersicon esculentum var. Ailsa Craig lines with reduced expression of either LePG or LeExp1 were crossed. Fruits from the third generation of progeny, homozygous for both transgenic constructs, were analyzed for firmness and other quality traits during ripening on or off the vine. In field-grown transgenic tomato fruit, suppression of LeExp1 or LePG alone did not significantly increase fruit firmness. However, fruits suppressed for both LePG and LeExp1 expression were significantly firmer throughout ripening and were less susceptible to deterioration during long-term storage. Juice prepared from the transgenic tomato fruit with reduced LePG and LeExp1 expression was more viscous than juice prepared from control fruit.
Toki, Fumiaki; Takahashi, Atsushi; Suzuki, Makoto; Ootake, Sayaka; Hirato, Junko; Kuwano, Hiroyuki
2011-05-01
We aimed to develop experimental models of hypoxia/ischemia-induced cholestasis using neonatal and infantile rats. Hypoxia/ischemia was induced in the bile duct (BD) by injecting prostaglandin (PG) at birth and/or by coagulation of the hepatic artery (CHA) at about 3 weeks after birth. The rats were divided into 6 groups: control; PG-injected; sham-operated with or without PG; CHA; and CHA + PG. CHA was also performed in adult rats. Liver specimens and blood samples were obtained at 5 weeks after birth, and immunohistochemical and biochemical examinations were performed. (1) BD proliferation with fibrosis (BDPF) was found in the intrahepatic portal tract in the CHA and CHA + PG groups. Low-grade BDPF was observed in the PG group. (2) Cyst formation in the extrahepatic BD (EBD) was observed in the porta hepatis of some rats in the CHA and CHA + PG groups. In these groups, the number of peribiliary vascular plexuses (PVPs) decreased. BD proliferation and infiltration of inflammatory cells were observed in the EBD wall in the CHA + PG group. (3) Ki-67 was expressed in BD and EBD cells in the CHA + PG group. (4) BDPF was not detected in adult rats with CHA. (5) Serum liver function tests indicated obstructive changes in the EBD in the CHA and CHA + PG groups. Reduced blood flow in the EBD during infancy induced BDPF and obstructive changes in the EBD, which may, along with immature PVP and inflammatory changes in the EBD, contribute to hypoxia/ischemia of the EBD.
Acute radiation sickness amelioration analysis. Technical report, 20 July 1990-19 July 1993
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, S.I.; Feister, A.J.; Bareis, D.L.
1994-05-01
Three tasks were conducted under the Acute Radiation Sickness Amelioration Analysis in support of the Defense Nuclear Agency (DNA) and NATO Army Armaments Group (NAAG) Project Group 29 (PG-29) on drugs for the prevention of radiation-induced nausea and vomiting: (1) documents were collected and entered into a data base, (2) data reviews and analyses were performed, and (3) PG-29 and Triservice meetings involving anti-emetic drug development were supported and documented. Approximately 2000 documents were collected, with 1424 complete bibliographic citations entered into a WordPerfect 5.1 data base. Eight reviews and analyses addressing different aspects of the safety and efficacy ofmore » the candidate anti-emetic drugs ondansetron and granistron were prepared. Support was provided for seven international PG-29 meetings and two U.S. Triservice meetings in which the efforts of PG-29 were discussed. These tasks have enabled the DNA and PG-29 to make good progress toward the goal of recommending a serotonin type-3 (5-HT3) receptor antagonist anti-emetic drug for use in military personnel.« less
Microbial Degradation of Propylene Glycol - Modelling Approach of a Batch Experiment
NASA Astrophysics Data System (ADS)
Dathe, Annette; Fernandez, Perrine; Bakken, Lars; Bloem, Esther; French, Helen
2016-04-01
De-icing chemicals are applied in large amounts at airports during winter conditions to keep the runways and aircrafts ice-free. At Gardermoen airport, Norway, most of the applied chemicals can be captured, but about 10 to 20 % infiltrate into the soil along the runways and during take-off. While the commonly used propylene glycol (PG) is easily degradable by local microbial communities, its biological oxygen demand is high, anoxic zones can develop and soluble Fe+2 and Mn+2 ions eventually can reach the groundwater. The objectives of the presented study are to quantify the mechanisms, which control the order of reduction processes in an unsaturated sandy soil, and to test whether measured redox potentials can help to determine underlying biogeochemical reactions. To investigate the mechanisms of microbial degradation, the water phase of soil samples from Gardermoen Airport was replaced by deionized water with 10 mMol PG or 10 mMol glutamate and the samples were incubated at 10°C for about two weeks. The gas phase was sampled and analyzed automatically every three hours. Microbial degradation of the substrate (PG or glutamate) was modelled following a Monod kinetics using the FME (Flexible Modelling Environment) package of R (Project for Statistical Computing). The model was calibrated against measurements of O2 depletion and CO2 production. The initial concentrations of O2, CO2 and PG or glutamate are known and microbial yields and stoichiometric constants can be calculated from the measurements. Parameter values for the initial microbial population size, maximum microbial growth rate, the half saturation constant, and microbial degradation and respiration rates were fitted using the FME package. The model accounts for carbon from the substrate (PG or glutamate) incorporated into the biomass. Results are promising, but because of the large number of parameters needed to fit a Monod kinetics it is challenging to accurately model a whole redox sequence. The ultimate goal of implementing PG degrading processes into a soil water transport model is still a challenge, and simpler approaches like a first- and second order kinetic are investigated and compared to the behavior of the Monod kinetic.
Rico, Mario C.; Dela Cadena, Raul A.; Kunapuli, Satya P.
2011-01-01
The P2Y12 receptor plays a crucial role in the regulation of platelet activation by several agonists, which is irreversibly antagonized by the active metabolite of clopidogrel, a widely used anti-thrombotic drug. In this study, we investigated whether reduction of platelet reactivity leads to reduced inflammatory responses using a rat model of erosive arthritis. We evaluated the effect of clopidogrel on inflammation in Lewis rats in a peptidoglycan polysaccharide (PG-PS)-induced arthritis model with four groups of rats: 1) untreated, 2) clopidogrel-treated, 3) PG-PS-induced, and 4) PG-PS-induced and clopidogrel-treated. There were significant differences between the PG-PS+clopidogrel group when compared to the PG-PS group including: increased joint diameter and clinical manifestations of inflammation, elevated plasma levels of pro-inflammatory cytokines (IL-1 beta, interferon (IFN) gamma, and IL-6), an elevated neutrophil blood count and an increased circulating platelet count. Plasma levels of IL-10 were significantly lower in the PG-PS+clopidogrel group compared to the PG-PS group. Plasma levels of platelet factor 4 (PF4) were elevated in both the PG-PS and the PG-PS+clopidogrel groups, however PF4 levels showed no difference upon clopidogrel treatment, suggesting that the pro- inflammatory effect of clopidogrel may be due to its action on cells other than platelets. Histology indicated an increase in leukocyte infiltration at the inflammatory area of the joint, increased pannus formation, blood vessel proliferation, subsynovial fibrosis and cartilage erosion upon treatment with clopidogrel in PG-PS-induced arthritis animals. In summary, animals treated with clopidogrel showed a pro-inflammatory effect in the PG-PS-induced arthritis animal model, which might not be mediated by platelets. Elucidation of the mechanism of clopidogrel-induced cell responses is important to understand the role of the P2Y12 receptor in inflammation. PMID:22028806
Glycosylation of DMP1 Is Essential for Chondrogenesis of Condylar Cartilage.
Weng, Y; Liu, Y; Du, H; Li, L; Jing, B; Zhang, Q; Wang, X; Wang, Z; Sun, Y
2017-12-01
The mandibular condylar cartilage (MCC) shoulders force for the subchondral bone during mastication. The cartilage matrix contains various large molecules, such as type I, II, and X collagens and proteoglycans (PGs), which jointly play essential roles in maintaining cartilage characteristics. PGs play key roles in maintaining the elasticity of cartilage and providing a cushion against mastication forces. In addition to the well-known PGs, DMP1-PG, which is the PG form of dentin matrix protein 1 (DMP1), is a newly identified PG. DMP1 is proteolytically processed in vivo, and the N-terminus is glycosylated into its PG form-that is, DMP1-PG, which is highly expressed not only in tooth and bone but also in the matrix of the MCC. However, the specific functions of DMP1-PG in the MCC remain unclear. In human temporomandibular joint osteoarthritis and hyperocclusion model rat specimens, PGs are significantly downregulated, and DMP1-PG is the most prominently affected PG. To further investigate the role of DMP1-PG in condylar chondrogenesis, a glycosylation site mutant (S 89 -G 89 ) mouse model was established with knock-in methods. In the MCC of the S89G-DMP1 mice, the glycosylation level of DMP1 was significantly downregulated, and a series of abnormal developmental and pathologic changes could be observed. The morphologic changes included thinner cartilage layers, deformations of the MCC, and disordered arrangements of the chondrocytes, and an earlier onset of temporomandibular joint osteoarthritis-like changes was observed. In addition, markers of chondrogenesis were downregulated, and the matrix of the MCC displayed OA phenotypes in the S89G-DMP1 mice. Further investigations showed that the transforming growth factor β signaling molecules were affected in the MCC after the loss of DMP1-PG. In addition, the loss of DMP1-PG significantly accelerated the progression of cartilage injuries in the hyperocclusion models. Given these findings, we investigated the significant role of DMP1-PG in the chondrogenesis and maintenance of MCC.
NASA Technical Reports Server (NTRS)
Winters, T. A.; Russell, P. S.; Kohli, M.; Dar, M. E.; Neumann, R. D.; Jorgensen, T. J.
1999-01-01
Human DNA polymerase and DNA ligase utilization for the repair of a major class of ionizing radiation-induced DNA lesion [DNA single-strand breaks containing 3'-phosphoglycolate (3'-PG)] was examined using a novel, chemically defined vector substrate containing a single, site-specific 3'-PG single-strand break lesion. In addition, the major human AP endonuclease, HAP1 (also known as APE1, APEX, Ref-1), was tested to determine if it was involved in initiating repair of 3'-PG-containing single-strand break lesions. DNA polymerase beta was found to be the primary polymerase responsible for nucleotide incorporation at the lesion site following excision of the 3'-PG blocking group. However, DNA polymerase delta/straightepsilon was also capable of nucleotide incorporation at the lesion site following 3'-PG excision. In addition, repair reactions catalyzed by DNA polymerase beta were found to be most effective in the presence of DNA ligase III, while those catalyzed by DNA polymerase delta/straightepsilon appeared to be more effective in the presence of DNA ligase I. Also, it was demonstrated that the repair initiating 3'-PG excision reaction was not dependent upon HAP1 activity, as judged by inhibition of HAP1 with neutralizing HAP1-specific polyclonal antibody.
Miyamoto, Gisela Cristiane; Franco, Katherinne Ferro Moura; van Dongen, Johanna M; Franco, Yuri Rafael Dos Santos; de Oliveira, Naiane Teixeira Bastos; Amaral, Diego Diulgeroglo Vicco; Branco, Amanda Nery Castelo; da Silva, Maria Liliane; van Tulder, Maurits W; Cabral, Cristina Maria Nunes
2018-03-10
To evaluate the effectiveness and cost-utility of the addition of different doses of Pilates to an advice for non-specific chronic low back pain (NSCLBP) from a societal perspective. Randomised controlled trial with economic evaluation. Physiotherapy clinic in São Paulo, Brazil. 296 patients with NSCLBP. All patients received advice and were randomly allocated to four groups (n=74 per group): booklet group (BG), Pilates once a week (Pilates group 1, PG1), Pilates twice a week (Pilates group 2, PG2) and Pilates three times a week (Pilates group 3, PG3). Primary outcomes were pain and disability at 6-week follow-up. Compared with the BG, all Pilates groups showed significant improvements in pain (PG1, mean difference (MD)=-1.2, 95% CI -2.2 to -0.3; PG2, MD=-2.3, 95% CI -3.2 to -1.4; PG3, MD=-2.1, 95% CI -3.0 to -1.1) and disability (PG1, MD=-1.9, 95% CI -3.6 to -0.1; PG2, MD=-4.7, 95% CI -6.4 to -3.0; PG3, MD=-3.3, 95% CI -5.0 to -1.6). Among the different doses, PG2 showed significant improvements in comparison with PG1 for pain (MD=-1.1, 95% CI -2.0 to -0.1) and disability (MD=-2.8, 95% CI -4.5 to -1.1). The cost-utility analysis showed that PG3 had a 0.78 probability of being cost-effective at a willingness-to-pay of £20 000 per quality-adjusted life-year gained. Adding two sessions of Pilates exercises to advice provided better outcomes in pain and disability than advice alone for patients with NSCLBP; non-specific elements such as greater attention or expectation might be part of this effect. The cost-utility analysis showed that Pilates three times a week was the preferred option. NCT02241538, Completed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Optical microvariability of selected PG QSOs
NASA Astrophysics Data System (ADS)
Jang, Minhwan
2005-02-01
This is a preliminary report of the continuing search for significant optical microvariability in a selected sample of radio-quiet and radio-loud quasi-stellar objects (QSOs). Total of 24 Paloma-Green (PG) quasars are observed. Among them, 17 objects are classified as radio-quiet and seven objects are classified radio-loud. In this classification, the ratio R, radio to optical flux density, is required to be less than 1 in order to assure the objects are reasonably radio-quiet. Two out of 17 radio-quiet QSOs and six out of eight radio-loud QSOs were microvariable. This apparent contrast in microvariations between radio-quiet and radio-loud QSOs does not provide firm support for the theoretical model utilizing discrete events in accretion disks and implies substantial support for models based on propagating shocks on relativistic jets as the likely process responsible for producing most of the microvariations are observed in AGNs.
Efficient Power Network Analysis with Modeling of Inductive Effects
NASA Astrophysics Data System (ADS)
Zeng, Shan; Yu, Wenjian; Hong, Xianlong; Cheng, Chung-Kuan
In this paper, an efficient method is proposed to accurately analyze large-scale power/ground (P/G) networks, where inductive parasitics are modeled with the partial reluctance. The method is based on frequency-domain circuit analysis and the technique of vector fitting [14], and obtains the time-domain voltage response at given P/G nodes. The frequency-domain circuit equation including partial reluctances is derived, and then solved with the GMRES algorithm with rescaling, preconditioning and recycling techniques. With the merit of sparsified reluctance matrix and iterative solving techniques for the frequency-domain circuit equations, the proposed method is able to handle large-scale P/G networks with complete inductive modeling. Numerical results show that the proposed method is orders of magnitude faster than HSPICE, several times faster than INDUCTWISE [4], and capable of handling the inductive P/G structures with more than 100, 000 wire segments.
NASA Technical Reports Server (NTRS)
Thorstensen, John R.; Ringwald, F. A.; Wade, Richard A.; Schmidt, Gary D.; Norsworthy, Jane E.
1991-01-01
This paper reports extensive optical observations on the PG0027 + 260 binary, carried out on August 1984 with the 1.3 McGraw-Hill telescope and Mark II spectrometer at Michigan-Dartmouth-MIT Observatory on Kitt Peak. It is shown that this object is an eclipsing novalike variable with an orbital period of 3.51 hr. The PG0027 + 260 displays several unexplained phenomena which are remarkably similar to those of the SW Sex, DW UMa, and V1315 Aql, which are eclipsing novalike stars with periods between 3 and 4 hrs. The eclipse of the PG0027 + 260 is modeled, and it is shown that, while the mean eclipse light curve is easy to match, there is no simple explanation for the variable depth.
A low-count reconstruction algorithm for Compton-based prompt gamma imaging
NASA Astrophysics Data System (ADS)
Huang, Hsuan-Ming; Liu, Chih-Chieh; Jan, Meei-Ling; Lee, Ming-Wei
2018-04-01
The Compton camera is an imaging device which has been proposed to detect prompt gammas (PGs) produced by proton–nuclear interactions within tissue during proton beam irradiation. Compton-based PG imaging has been developed to verify proton ranges because PG rays, particularly characteristic ones, have strong correlations with the distribution of the proton dose. However, accurate image reconstruction from characteristic PGs is challenging because the detector efficiency and resolution are generally low. Our previous study showed that point spread functions can be incorporated into the reconstruction process to improve image resolution. In this study, we proposed a low-count reconstruction algorithm to improve the image quality of a characteristic PG emission by pooling information from other characteristic PG emissions. PGs were simulated from a proton beam irradiated on a water phantom, and a two-stage Compton camera was used for PG detection. The results show that the image quality of the reconstructed characteristic PG emission is improved with our proposed method in contrast to the standard reconstruction method using events from only one characteristic PG emission. For the 4.44 MeV PG rays, both methods can be used to predict the positions of the peak and the distal falloff with a mean accuracy of 2 mm. Moreover, only the proposed method can improve the estimated positions of the peak and the distal falloff of 5.25 MeV PG rays, and a mean accuracy of 2 mm can be reached.
Zabik, John M.; Seiber, James N.
1993-01-01
Atmospheric transport of organophosphate pesticides from California's Central Valley to the Sierra Nevada mountains was assessed by collecting air- and wet-deposition samples during December, January, February, and March, 1990 to 1991. Large-scale spraying of these pesticides occurs during December and January to control insect infestations in valley orchards. Sampling sites were placed at 114- (base of the foothills), 533-, and 1920-m elevations. Samples acquired at these sites contained chlorpyrifos [phosphorothioic acid; 0,0-diethyl 0-(3,5,6-trichloro-2-pyridinyl) ester], parathion [phosphorothioic acid, 0-0-diethylo-(4-nitrophenyl) ester], diazinon {phosphorothioic acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester} diazinonoxon {phosphoric acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester}, and paraoxon [phosphoric acid, 0,0-diethyl 0-(4-nitrophenyl) ester] in both air and wet deposition samples. Air concentrations of chloropyrifos, diazinon and parathion ranged from 13 to 13 000 pg/m3 at the base of the foothills. At 533-m air concentrations were below the limit of quantification (1.4 pg/m3) to 83 pg/m3 and at 1920 m concentrations were below the limit of quantification. Concentrations in wet deposition varied with distance and elevation from the Central Valley. Rainwater concentrations at the base of the foot hills ranged from 16 to 7600 pg/mL. At 533-m rain and snow water concentrations ranged from below the limit of quantification (1.3 pg/mL) to 140 pg/mL and at 1920 m concentrations ranged from below the limit of quantification to 48 pg/mL. These findings indicate that atmospheric transport of pesticides applied in the valley to the Sierra Nevada mountains is occurring, but the levels decrease as distance and elevation increase from the valley floor.
Brouwers, Melissa C; Vukmirovic, Marija; Spithoff, Karen; Makarski, Julie
2017-03-09
Practice guidelines (PGs) can assist health care practitioners and patients to make decisions about health care options. A key component of high quality PGs is the consideration of patient values and preferences. A mixed methods study was conducted to understand optimal approaches to patient engagement in the development of cancer PGs. Cancer patients, survivors, family members and caregivers were recruited from cancer clinics, follow-up clinics, community support programs, a provincial patient and family advisory committee, and a provincial cancer PG development program. Participants attended a workshop, completed a survey, or participated in a telephone interview, to provide information about PG awareness, attitudes, information needs, training, engagement approaches and barriers and facilitators. Forty-one participants (12 workshop attendees, 21 survey respondents and 8 interviewees) provided data. For those with no PG development experience, fewer than half were previously aware of PGs but perceived several benefits to the inclusion of this perspective. Common barriers to participation across the groups were time commitment, duration of the PG development process, and financial costs. Positive beliefs about the contributions that could be made and practical considerations (e.g., orientation and training, defined roles and expectations) were identified as key features in the successful integration of patients into the PG development process. There was no single model of engagement favored over another. Study results align with similar studies in other contexts and with international patient engagement efforts. Findings are being used to test new patient engagement models in a programmatic PG development initiative in Ontario, Canada.
Lendoiro, Elena; Jiménez-Morigosa, Cristian; Cruz, Angelines; Páramo, Mario; López-Rivadulla, Manuel; de Castro, Ana
2017-01-01
Amphetamine-type-stimulants (ATS) are the second most commonly used group of illicit drugs worldwide. However, in the last few years, new psychoactive substances (NPS) with stimulant effects have appeared on the illegal market, which are not detected with traditional analytical methods. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination in hair of classic ATS (amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine and 3,4-methylenedioxyamphetamine), synthetic cathinones (methylone, methedrone, mephedrone, 3,4-methylenedioxypyrovalerone, (±)-4-fluoromethamphetamine and 4-fluoromethcathinone), synthetic piperazines (1-(3-chlorophenyl)piperazine (mCPP) and 3-trifluoromethylphenylpiperazine), and medicines (trazodone and phenazone) that produce mCPP as a metabolite, was developed and fully validated. Hair samples (30 mg) were incubated in acid methanol (0.1% HCl) and extracted by a mixed-mode solid-phase extraction. Chromatographic separation was performed using an Atlantis T3 (3 µm; 2.1x50 mm) analytical column, and ammonium formate 2 mM pH 3 and acetonitrile as mobile phase. The method was validated, including selectivity (no endogenous or exogenous interferences); linearity (2-20 to 2000-4000 pg/mg); limits of detection (0.2 to 5 pg/mg) and quantification (2 to 20 pg/mg); accuracy (93.4-109.4% of target concentration); imprecision (%CV<11.6%); extraction recovery (40.5-92.1%); matrix effect (24.1-227.2%); process efficiency (9.8-165.7%) and stability in the autosampler (-14.5% of loss). The method was applied to the analysis of 16 hair samples. Amphetamine (n=7; 69.1-777.1 pg/mg), methamphetamine (n=3; 120.4-1,538.9 pg/mg), MDA (n=2; 27.8-135.4 pg/mg) and MDMA (n=8; 73.4-3,654.5 pg/mg) were found. Moreover, 10 positive results for mCPP were detected (341.7->4000 pg/mg); however, in all cases trazodone identification (2085.3->4000 pg/mg) probed a licit origin of mCPP. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
McArt, J A A; Nydam, D V; Oetzel, G R
2012-05-01
The purpose was to determine the effect of oral propylene glycol (PG) administration in fresh cows diagnosed with subclinical ketosis (SCK). Measured outcomes were development of displaced abomasum (DA) and removal from herd in the first 30 d in milk (DIM), conception to first service, and time to conception within 150 DIM. Cows from 4 freestall dairy herds (2 in New York and 2 in Wisconsin) were each tested 6 times for SCK from 3 to 16 DIM on Mondays, Wednesdays, and Fridays using the Precision Xtra meter (Abbott Laboratories, Abbott Park, IL). Subclinical ketosis was defined as a blood β-hydroxybutyrate concentration of 1.2 to 2.9 mmol/L. Cows with SCK were randomized to treatment group (oral PG) or untreated control group (no PG); treatment cows were orally drenched with 300 mL of PG once daily from the day they tested 1.2 to 2.9 mmol/L until the day they tested <1.2 mmol/L. Mixed effects multivariable Poisson regression was used to assess the effect of PG on DA, removal from herd, and conception to first service; a semiparametric proportional hazards model was used to evaluate the days-to-conception outcome. A total of 741 of 1,717 (43.2%) eligible enrolled cows had at least 1 β-hydroxybutyrate test of 1.2 to 2.9 mmol/L. Of these, 372 were assigned to the PG treatment group and 369 to the control group. Thirty-nine cows (5.3%) developed a DA after testing positive for SCK and 30 cows (4.0%) died or were sold within the first 30 DIM. Based on risk ratios, control cows were 1.6 times more likely [95% confidence interval (CI)=1.3 to 2.0] to develop a DA and 2.1 times more likely (95% CI=1.2 to 3.6) to die or be sold than cows treated with PG. In addition, PG-treated cows were 1.3 times more likely (risk ratio 95% CI=1.1 to 1.5) to conceive at first insemination than control cows in 3 of the herds. No difference was observed in days to conception within 150 DIM between treatment groups (hazard ratio for PG cows=1.1, 95% CI=0.8 to 1.4), with a median time to conception of 100 d (95% CI=93 to 111) and 104 d (95% CI=95 to 114) for PG-treated and control cows, respectively. These results show that intensive detection of SCK, followed by treatment of positive cows with oral PG decreased the risk of developing a DA or leaving the herd within the first 30 DIM and increased the risk of conception to first service. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Dynamic and thermodynamic mechanisms of TFA adsorption by particulate matter.
Guo, Junyu; Zhai, Zihan; Wang, Lei; Wang, Ziyuan; Wu, Jing; Zhang, Boya; Zhang, Jianbo
2017-06-01
Trifluoroacetic acid (TFA) in the atmosphere is produced by degradation of hydrochlorofluorocarbons and hydrofluorocarbons. In recent years, TFA has attracted global attention because of increased environmental concentrations, biological toxicity and accumulation in aqueous environments. This study focused on the mechanisms underlying the adsorption of TFA by particulate matter to identify the appropriate descriptive model for this process and thus improve estimation of TFA adsorption in future environmental monitoring. Onsite gas and particle phase sampling in Beijing, China, and subsequent measurement of TFA concentrations indicated that the TFA concentration in the gas phase (1396 ± 225 pg m -3 ) was much higher than that in the particle phase (62 ± 8 pg m -3 ) and that monthly concentrations varied seasonally with temperature. Based on the field results and analysis, an adsorption experiment of TFA on soot was then conducted at three different temperatures (293, 303, and 313 K) to provide parameters for kinetic and thermodynamic modelling. The proportion of atmospheric TFA concentration in the gas phase increased with temperature, indicating that temperature affected the phase distribution of TFA. The subsequent kinetic and thermodynamic modelling showed that the adsorption of TFA by soot could be described well by the Bangham kinetic model. The adsorption was controlled by diffusion, and the key mechanism was physical adsorption. The adsorption behavior can be well described by the Langmuir isotherm model. The calculated thermodynamic parameters ΔG° (-2.34, -1.25, and -0.15 kJ mol -1 at 293, 303, and 313 K, respectively), ΔH° (-34.34 kJ mol -1 ), and ΔS° (-109.22 J mol -1 K -1 ) for TFA adsorption by soot were negative, indicating that adsorption was a spontaneous, exothermic process. Copyright © 2017 Elsevier Ltd. All rights reserved.
Adekunte, Adefunke O; Tiwari, Brijesh K; O'Donnell, Colm P
2010-09-01
Quantitative exposure assessment is a useful technique to investigate the risk from contaminants in the food chain. The objective of this study was to develop a probabilistic exposure assessment model for dioxins (PCDD/Fs) and dioxin-like PCBs (DL-PCBs) in pasteurised bovine milk. Mean dioxins and DL-PCBs (non-ortho and mono-ortho PCBs) concentrations (pg WHO-TEQ g(-1)) in bovine milk were estimated as 0.06 ± 0.07 pg WHO-TEQ g(-1) for dioxins and 0.08 ± 0.07 pg WHO-TEQ g(-1) for DL-PCBs using Monte Carlo simulation. The simulated model estimated mean exposure for dioxins was 0.19 ± 0.29 pg WHO-TEQ kg(-1)bw d(-1) and 0.14 ± 0.22 pg WHO-TEQ kg(-1) bw d(-1) and for DL-PCBs was 0.25 ± 0.30 pg WHO-TEQ kg(-1) bw d(-1) and 0.19 ± 0.22 pg WHO-TEQ kg(-1) bw d(-1) for men and women, respectively. This study showed that the mean dioxins and DL-PCBs exposure from consumption of pasteurised bovine milk is below the provisional maximum tolerable monthly intake of 70 pg TEQ kg(-1) bw month(-1) (equivalent of 2.3 pg TEQ kg(-1) bw d(-1)) recommended by the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (JECFA). Results from this study also showed that the estimated dioxins and DL-PCBs concentration in pasteurised bovine milk is comparable to those reported in previous studies. Copyright © 2010 Elsevier Ltd. All rights reserved.
Roth, Nadine; Moosmann, Bjoern; Auwärter, Volker
2013-02-01
For analysis of hair samples derived from a pilot study ('in vivo' contamination of hair by sidestream marijuana smoke), an LC-MS/MS method was developed and validated for the simultaneous quantification of Δ9-tetrahydrocannabinolic acid A (THCA-A), Δ9-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD). Hair samples were extracted in methanol for 4 h under occasional shaking at room temperature, after adding THC-D(3), CBN-D(3), CBD-D(3) and THCA-A-D(3) as an in-house synthesized internal standard. The analytes were separated by gradient elution on a Luna C18 column using 0.1% HCOOH and ACN + 0.1% HCOOH. Data acquisition was performed on a QTrap 4000 in electrospray ionization-multi reaction monitoring mode. Validation was carried out according to the guidelines of the German Society of Toxicological and Forensic Chemistry (GTFCh). Limit of detection and lower limit of quantification were 2.5 pg/mg for THCA-A and 20 pg/mg for THC, CBN and CBD. A linear calibration model was applicable for all analytes over a range of 2.5 pg/mg or 20 pg/mg to 1000 pg/mg, using a weighting factor 1/x. Selectivity was shown for 12 blank hair samples from different sources. Accuracy and precision data were within the required limits for all analytes (bias between -0.2% and 6.4%, RSD between 3.7% and 11.5%). The dried hair extracts were stable over a time period of one to five days in the dark at room temperature. Processed sample stability (maximum decrease of analyte peak area below 25%) was considerably enhanced by adding 0.25% lecithin (w/v) in ACN + 0.1% HCOOH for reconstitution. Extraction efficiency for CBD was generally very low using methanol extraction. Hence, for effective extraction of CBD alkaline hydrolysis is recommended. Copyright © 2013 John Wiley & Sons, Ltd.
Vazir, Shahnaz; Engle, Patrice; Balakrishna, Nagalla; Griffiths, Paula L.; Johnson, Susan L.; Creed-Kanashiro, Hilary; Rao, Sylvia Fernandez; Shroff, Monal R.; Bentley, Margaret E.
2012-01-01
Inadequate feeding and care may contribute to high rates of stunting and underweight among children in rural families in India. This cluster-randomized trial tested the hypothesis that teaching caregivers appropriate complementary feeding, and strategies for how to feed and play responsively through home-visits would increase children’s dietary intake, growth, and development compared to home-visit-complementary feeding education alone or routine care. Sixty villages in Andhra Pradesh were randomized into 3 groups1 of 20 villages with 200 mother-infant dyads in each group. The Control Group (CG), received routine Integrated Child Development Services (ICDS); the Complementary Feeding Group (CFG), received the ICDS plus the World Health Organization recommendations on breastfeeding and complementary foods; and the Responsive Complementary Feeding & Play Group (RCF&PG) received the same intervention as the CFG plus skills for responsive feeding and psychosocial stimulation. Both intervention groups received bi-weekly visits by trained village women. The groups did not differ at 3 months on socioeconomic status, maternal and child nutritional indices and maternal depression. After controlling for potential confounding factors using the mixed models approach, the twelve-month intervention to the CFG and RCF&PG significantly (p<0.05) increased median intakes of energy, protein, Vitamin-A, calcium (CFG), iron and zinc, reduced stunting (0.19, CI: 0.0–0.4) in the CFG (but not RCF&PG) and increased (p<0.01) Bayley Mental Development scores(Mean=3.1, CI: 0.8–5.3) in the RCF&PG (but not CFG) compared to CG. Community-based educational interventions can improve dietary intake, length (CFG), and mental development (RCF&PG) for children under two years in food-secure rural Indian families. PMID:22625182
The simulated climate of the Last Glacial Maximum and insights into the global marine carbon cycle
NASA Astrophysics Data System (ADS)
Buchanan, Pearse J.; Matear, Richard J.; Lenton, Andrew; Phipps, Steven J.; Chase, Zanna; Etheridge, David M.
2016-12-01
The ocean's ability to store large quantities of carbon, combined with the millennial longevity over which this reservoir is overturned, has implicated the ocean as a key driver of glacial-interglacial climates. However, the combination of processes that cause an accumulation of carbon within the ocean during glacial periods is still under debate. Here we present simulations of the Last Glacial Maximum (LGM) using the CSIRO Mk3L-COAL (Carbon-Ocean-Atmosphere-Land) earth system model to test the contribution of physical and biogeochemical processes to ocean carbon storage. For the LGM simulation, we find a significant global cooling of the surface ocean (3.2 °C) and the expansion of both minimum and maximum sea ice cover broadly consistent with proxy reconstructions. The glacial ocean stores an additional 267 Pg C in the deep ocean relative to the pre-industrial (PI) simulation due to stronger Antarctic Bottom Water formation. However, 889 Pg C is lost from the upper ocean via equilibration with a lower atmospheric CO2 concentration and a global decrease in export production, causing a net loss of carbon relative to the PI ocean. The LGM deep ocean also experiences an oxygenation ( > 100 mmol O2 m-3) and deepening of the calcite saturation horizon (exceeds the ocean bottom) at odds with proxy reconstructions. With modifications to key biogeochemical processes, which include an increased export of organic matter due to a simulated release from iron limitation, a deepening of remineralisation and decreased inorganic carbon export driven by cooler temperatures, we find that the carbon content of the glacial ocean can be sufficiently increased (317 Pg C) to explain the reduction in atmospheric and terrestrial carbon at the LGM (194 ± 2 and 330 ± 400 Pg C, respectively). Assuming an LGM-PI difference of 95 ppm pCO2, we find that 55 ppm can be attributed to the biological pump, 28 ppm to circulation changes and the remaining 12 ppm to solubility. The biogeochemical modifications also improve model-proxy agreement in export production, carbonate chemistry and dissolved oxygen fields. Thus, we find strong evidence that variations in the oceanic biological pump exert a primary control on the climate.
NASA Astrophysics Data System (ADS)
Wu, Q.; Song, J.; Wang, J.; Chen, S.; Yu, B.; Liao, L.
2016-12-01
Monitoring the dynamics of leaf area index (LAI) throughout the life-cycle of forests (from seeding to maturity) is vital for simulating forest growth and quantifying carbon sequestration. However, all current global LAI produts show extremely low accuracy in forests and the coarse spatial resolution(nearly 1-km) mismatch with the spatial scale of forest inventory plots (nearly 26m*26m). To date, several studies have explored the possibility of satellite data to classify forest succession or predict stand age. And a few studies have explored the potential of using long term Landsat data to monitor the growing trend of forests, but no studies have quantified the inter-annual and intra-annual LAI dynamics along with forest succession. Vegetation indexes are not perfect variables in quantifying forest foliage dynamics. Hallet (1995) suggested remote sensing of biophysical characteristics should shift away from direct inference from vegetation indices toward more physically based algorithms. This work intends to be a pioneer example for improving the accuracy of forests LAI and providing temporal-spatial matching LAI datasets for monitoring forest processes. We integrates the Geometric-Optical and Radiative Transfer (GORT) model with the Physiological Principles Predicting Growth (3-PG) model to improve the estimation of the forest canopy LAI dynamics. Reflectance time-series data from 1987 to 2015 were collected and preprocessed for forests in southern China, using all available Landsat data (with <80% cloud). Effective LAI and true LAI were field measured to validate our results using various instruments, including digital hemispheric photographs (DHP), LAI-2000 Plant Canopy Analyzer (LI-COR), and Tracing radiation and Architecture of Canopies (TRAC). Results show that the relationship between spectral metrics of satellite images and forest LAI is clear in early stages before maturity. 3-PG provide accurate inter-annual trend of forest LAI, while satellite images provide clear intra-annual LAI dynamics. We concluded that the GORT-3PG model improved the LAI estimation significantly of forest stands. Improving forest LAI estimates will help inform forest management policy and such methods may be applied in other similar forests.
Figueroa, Melania; Alderman, Stephen; Garvin, David F.; Pfender, William F.
2013-01-01
Puccinia graminis causes stem rust, a serious disease of cereals and forage grasses. Important formae speciales of P. graminis and their typical hosts are P. graminis f. sp. tritici (Pg-tr) in wheat and barley, P. graminis f. sp. lolii (Pg-lo) in perennial ryegrass and tall fescue, and P. graminis f. sp. phlei-pratensis (Pg-pp) in timothy grass. Brachypodium distachyon is an emerging genetic model to study fungal disease resistance in cereals and temperate grasses. We characterized the P. graminis-Brachypodium pathosystem to evaluate its potential for investigating incompatibility and non-host resistance to P. graminis. Inoculation of eight Brachypodium inbred lines with Pg-tr, Pg-lo or Pg-pp resulted in sporulating lesions later accompanied by necrosis. Histological analysis of early infection events in one Brachypodium inbred line (Bd1-1) indicated that Pg-lo and Pg-pp were markedly more efficient than Pg-tr at establishing a biotrophic interaction. Formation of appressoria was completed (60–70% of germinated spores) by 12 h post-inoculation (hpi) under dark and wet conditions, and after 4 h of subsequent light exposure fungal penetration structures (penetration peg, substomatal vesicle and primary infection hyphae) had developed. Brachypodium Bd1-1 exhibited pre-haustorial resistance to Pg-tr, i.e. infection usually stopped at appressorial formation. By 68 hpi, only 0.3% and 0.7% of the Pg-tr urediniospores developed haustoria and colonies, respectively. In contrast, development of advanced infection structures by Pg-lo and Pg-pp was significantly more common; however, Brachypodium displayed post-haustorial resistance to these isolates. By 68 hpi the percentage of urediniospores that only develop a haustorium mother cell or haustorium in Pg-lo and Pg-pp reached 8% and 5%, respectively. The formation of colonies reached 14% and 13%, respectively. We conclude that Brachypodium is an apt grass model to study the molecular and genetic components of incompatiblity and non-host resistance to P. graminis. PMID:23441218
Stähli, Christoph; James-Bhasin, Mark; Nazhat, Showan N
2015-02-28
Copper ions represent a promising angiogenic agent but are associated with cytotoxicity at elevated concentrations. Phosphate-based glasses (PGs) exhibit adjustable dissolution properties and allow for controlled ion release. This study examined the formation of capillary-like networks by SVEC4-10 endothelial cells (ECs) seeded in a three-dimensional (3D) type I collagen hydrogel matrix mixed with PG particles of the formulation 50P2O5-30CaO-(20-x)Na2O-xCuO (x=0 and 10 mol%). Copper and total phosphorus release decreased over time and was more sustained in the case of 10% CuO PG. Moreover, increasing the concentration of 10% CuO PG in collagen substantially delayed dissolution along with preferential release of copper. A 3D morphometric characterization method based on confocal laser scanning microscopy image stacks was developed in order to quantify EC network length, connectivity and branching. Network length was initially reduced in a concentration-dependent fashion by 10% CuO PG and, to a lesser extent, by 0% CuO PG, but reached values identical to the non-PG control by day 5 in culture. This reduction was attributed to a PG-mediated decrease in cell metabolic activity while cell proliferation as well as network connectivity and branching were independent of PG content. Gene expression of matrix metalloproteinases (MMP)-1 and -2 was up-regulated by PGs, indicating that MMPs did not play a critical role in network growth. The relationship between ion release and EC morphogenesis in 3D provided in this study is expected to contribute to an ultimately successful pro-angiogenic application of CuO-doped PGs. Copyright © 2015 Elsevier B.V. All rights reserved.
Regional contribution to variability and trends of global gross primary productivity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Min; Rafique, Rashid; Asrar, Ghassem R.
Terrestrial gross primary productivity (GPP) is the largest component of the global carbon cycle and a key process for understanding land ecosystems dynamics. In this study, we used GPP estimates from a combination of eight global biome models participating in the Inter-Sectoral Impact-Model Intercomparison Project phase 2a (ISIMIP2a), the Moderate Resolution Spectroradiometer (MODIS) GPP product, and a data-driven product (Model Tree Ensemble, MTE) to study the spatiotemporal variability of GPP at the regional and global levels. We found the 2000-2010 total global GPP estimated from the model ensemble to be 117±13 Pg C yr-1 (mean ± 1 standard deviation), whichmore » was higher than MODIS (112 Pg C yr-1), and close to the MTE (120 Pg C yr-1). The spatial patterns of MODIS, MTE and ISIMIP2a GPP generally agree well, but their temporal trends are different, and the seasonality and inter-annual variability of GPP at the regional and global levels are not completely consistent. For the model ensemble, Tropical Latin America contributes the most to global GPP, Asian regions contribute the most to the global GPP trend, the Northern Hemisphere regions dominate the global GPP seasonal variations, and Oceania is likely the largest contributor to inter-annual variability of global GPP. However, we observed large uncertainties across the eight ISIMIP2a models, which are probably due to the differences in the formulation of underlying photosynthetic processes. The results of this study are useful in understanding the contributions of different regions to global GPP and its spatiotemporal variability, how the model- and observational-based GPP estimates differ from each other in time and space, and the relative strength of the eight models. Our results also highlight the models’ ability to capture the seasonality of GPP that are essential for understanding the inter-annual and seasonal variability of GPP as a major component of the carbon cycle.« less
NASA Astrophysics Data System (ADS)
Zhang, H. F.; Chen, B. Z.; van der Laan-Luijkx, I. T.; Machida, T.; Matsueda, H.; Sawa, Y.; Fukuyama, Y.; Labuschagne, C.; Langenfelds, R.; van der Schoot, M.; Xu, G.; Yan, J. W.; Zhou, L. X.; Tans, P. P.; Peters, W.
2013-10-01
Current estimates of the terrestrial carbon fluxes in Asia ("Asia" refers to lands as far west as the Urals and is divided into Boreal Eurasia, Temperate Eurasia and tropical Asia based on TransCom regions) show large uncertainties particularly in the boreal and mid-latitudes and in China. In this paper, we present an updated carbon flux estimate for Asia by introducing aircraft CO2 measurements from the CONTRAIL (Comprehensive Observation Network for Trace gases by Airline) program into an inversion modeling system based on the CarbonTracker framework. We estimated the averaged annual total Asian terrestrial land CO2 sink was about -1.56 Pg C yr-1 over the period 2006-2010, which offsets about one-third of the fossil fuel emission from Asia (+4.15 Pg C yr-1). The uncertainty of the terrestrial uptake estimate was derived from a set of sensitivity tests and ranged from -1.07 to -1.80 Pg C yr-1, comparable to the formal Gaussian error of ±1.18 Pg C yr-1 (1-sigma). The largest sink was found in forests, predominantly in coniferous forests (-0.64 Pg C yr-1) and mixed forests (-0.14 Pg C yr-1); and the second and third large carbon sinks were found in grass/shrub lands and crop lands, accounting for -0.44 Pg C yr-1 and -0.20 Pg C yr-1, respectively. The peak-to-peak amplitude of inter-annual variability (IAV) was 0.57 Pg C yr-1 ranging from -1.71 Pg C yr-1 to -2.28 Pg C yr-1. The IAV analysis reveals that the Asian CO2 sink was sensitive to climate variations, with the lowest uptake in 2010 concurrent with summer flood/autumn drought and the largest CO2 sink in 2009 owing to favorable temperature and plentiful precipitation conditions. We also found the inclusion of the CONTRAIL data in the inversion modeling system reduced the uncertainty by 11% over the whole Asian region, with a large reduction in the southeast of Boreal Eurasia, southeast of Temperate Eurasia and most Tropical Asian areas.
Rastegari, Banafsheh; Karbalaei-Heidari, Hamid Reza; Zeinali, Sedigheh; Sheardown, Heather
2017-10-01
In present investigation, two glucose based smart tumor-targeted drug delivery systems coupled with enzyme-sensitive release strategy are introduced. Magnetic nanoparticles (Fe 3 O 4 ) were grafted with carboxymethyl chitosan (CS) and β-cyclodextrin (β-CD) as carriers. Prodigiosin (PG) was used as the model anti-tumor drug, targeting aggressive tumor cells. The morphology, properties and composition and grafting process were characterized by transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), vibration sample magnetometer (VSM), X-ray diffraction (XRD) analysis. The results revealed that the core crystal size of the nanoparticles synthesized were 14.2±2.1 and 9.8±1.4nm for β-CD and CS-MNPs respectively when measured using TEM; while dynamic light scattering (DLS) gave diameters of 121.1 and 38.2nm. The saturation magnetization (Ms) of bare magnetic nanoparticles is 50.10emucm -3 , while modification with β-CD and CS gave values of 37.48 and 65.01emucm -3 , respectively. The anticancer compound, prodigiosin (PG) was loaded into the NPs with an encapsulation efficiency of approximately 81% for the β-CD-MNPs, and 92% for the CS-MNPs. This translates to a drug loading capacity of 56.17 and 59.17mg/100mg MNPs, respectively. Measurement of in vitro release of prodigiosin from the loaded nanocarriers in the presence of the hydrolytic enzymes, alpha-amylase and chitosanase showed that 58.1 and 44.6% of the drug was released after one-hour of incubation. Cytotoxicity studies of PG-loaded nanocarriers on two cancer cell lines, MCF-7 and HepG2, and on a non-cancerous control, NIH/3T3 cells, revealed that the drug loaded nanoparticles had greater efficacy on the cancer cell lines. The selective index (SI) for free PG on MCF-7 and HepG2 cells was 1.54 and 4.42 respectively. This parameter was reduced for PG-loaded β-CD-MNPs to 1.27 and 1.85, while the SI for CS-MNPs improved considerably to 7.03 on MCF-7 cells. Complementary studies by fluorescence and confocal microscopy and flow cytometry confirm specific targeting of the nanocarriers to the cancer cells. The results suggest that CS-MNPs have higher potency and are better able to target the prodigiosin toxicity effect on cancerous cells than β-CD-MNPs. Copyright © 2017 Elsevier B.V. All rights reserved.
Surface field theories of point group symmetry protected topological phases
NASA Astrophysics Data System (ADS)
Huang, Sheng-Jie; Hermele, Michael
2018-02-01
We identify field theories that describe the surfaces of three-dimensional bosonic point group symmetry protected topological (pgSPT) phases. The anomalous nature of the surface field theories is revealed via a dimensional reduction argument. Specifically, we study three different surface field theories. The first field theory is quantum electrodynamics in three space-time dimensions (QED3) with four flavors of fermions. We show this theory can describe the surfaces of a majority of bosonic pgSPT phases protected by a single mirror reflection, or by Cn v point group symmetry for n =2 ,3 ,4 ,6 . The second field theory is a variant of QED3 with charge-1 and charge-3 Dirac fermions. This field theory can describe the surface of a reflection symmetric pgSPT phase built by placing an E8 state on the mirror plane. The third field theory is an O (4 ) nonlinear sigma model with a topological theta term at θ =π , or, equivalently, a noncompact CP1 model. Using a coupled wire construction, we show this is a surface theory for bosonic pgSPT phases with U (1 ) ×Z2P symmetry. For the latter two field theories, we discuss the connection to gapped surfaces with topological order. Moreover, we conjecture that the latter two field theories can describe surfaces of more general bosonic pgSPT phases with Cn v point group symmetry.
Terrestrial gross carbon dioxide uptake: global distribution and covariation with climate.
Beer, Christian; Reichstein, Markus; Tomelleri, Enrico; Ciais, Philippe; Jung, Martin; Carvalhais, Nuno; Rödenbeck, Christian; Arain, M Altaf; Baldocchi, Dennis; Bonan, Gordon B; Bondeau, Alberte; Cescatti, Alessandro; Lasslop, Gitta; Lindroth, Anders; Lomas, Mark; Luyssaert, Sebastiaan; Margolis, Hank; Oleson, Keith W; Roupsard, Olivier; Veenendaal, Elmar; Viovy, Nicolas; Williams, Christopher; Woodward, F Ian; Papale, Dario
2010-08-13
Terrestrial gross primary production (GPP) is the largest global CO(2) flux driving several ecosystem functions. We provide an observation-based estimate of this flux at 123 +/- 8 petagrams of carbon per year (Pg C year(-1)) using eddy covariance flux data and various diagnostic models. Tropical forests and savannahs account for 60%. GPP over 40% of the vegetated land is associated with precipitation. State-of-the-art process-oriented biosphere models used for climate predictions exhibit a large between-model variation of GPP's latitudinal patterns and show higher spatial correlations between GPP and precipitation, suggesting the existence of missing processes or feedback mechanisms which attenuate the vegetation response to climate. Our estimates of spatially distributed GPP and its covariation with climate can help improve coupled climate-carbon cycle process models.
Intentional strategies that make co-actors more predictable: the case of signaling.
Pezzulo, Giovanni; Dindo, Haris
2013-08-01
Pickering & Garrod (P&G) explain dialogue dynamics in terms of forward modeling and prediction-by-simulation mechanisms. Their theory dissolves a strict segregation between production and comprehension processes, and it links dialogue to action-based theories of joint action. We propose that the theory can also incorporate intentional strategies that increase communicative success: for example, signaling strategies that help remaining predictable and forming common ground.
NASA Astrophysics Data System (ADS)
Zhang, H. F.; Chen, B. Z.; Machida, T.; Matsueda, H.; Sawa, Y.; Fukuyama, Y.; Langenfelds, R.; van der Schoot, M.; Xu, G.; Yan, J. W.; Cheng, M. L.; Zhou, L. X.; Tans, P. P.; Peters, W.
2014-06-01
Current estimates of the terrestrial carbon fluxes in Asia show large uncertainties particularly in the boreal and mid-latitudes and in China. In this paper, we present an updated carbon flux estimate for Asia ("Asia" refers to lands as far west as the Urals and is divided into boreal Eurasia, temperate Eurasia and tropical Asia based on TransCom regions) by introducing aircraft CO2 measurements from the CONTRAIL (Comprehensive Observation Network for Trace gases by Airline) program into an inversion modeling system based on the CarbonTracker framework. We estimated the averaged annual total Asian terrestrial land CO2 sink was about -1.56 Pg C yr-1 over the period 2006-2010, which offsets about one-third of the fossil fuel emission from Asia (+4.15 Pg C yr-1). The uncertainty of the terrestrial uptake estimate was derived from a set of sensitivity tests and ranged from -1.07 to -1.80 Pg C yr-1, comparable to the formal Gaussian error of ±1.18 Pg C yr-1 (1-sigma). The largest sink was found in forests, predominantly in coniferous forests (-0.64 ± 0.70 Pg C yr-1) and mixed forests (-0.14 ± 0.27 Pg C yr-1); and the second and third large carbon sinks were found in grass/shrub lands and croplands, accounting for -0.44 ± 0.48 Pg C yr-1 and -0.20 ± 0.48 Pg C yr-1, respectively. The carbon fluxes per ecosystem type have large a priori Gaussian uncertainties, and the reduction of uncertainty based on assimilation of sparse observations over Asia is modest (8.7-25.5%) for most individual ecosystems. The ecosystem flux adjustments follow the detailed a priori spatial patterns by design, which further increases the reliance on the a priori biosphere exchange model. The peak-to-peak amplitude of inter-annual variability (IAV) was 0.57 Pg C yr-1 ranging from -1.71 Pg C yr-1 to -2.28 Pg C yr-1. The IAV analysis reveals that the Asian CO2 sink was sensitive to climate variations, with the lowest uptake in 2010 concurrent with a summer flood and autumn drought and the largest CO2 sink in 2009 owing to favorable temperature and plentiful precipitation conditions. We also found the inclusion of the CONTRAIL data in the inversion modeling system reduced the uncertainty by 11% over the whole Asian region, with a large reduction in the southeast of boreal Eurasia, southeast of temperate Eurasia and most tropical Asian areas.
Liu, Wei-wei; Wang, Xiao-ke; Lu, Fei; Ouyang, Zhi-yun
2015-09-01
As a dominant part of terrestrial ecosystems, forest ecosystem plays an important role in absorbing atmospheric CO2 and global climate change mitigation. From the aspects of zonal climate and geographical distribution, the present carbon stocks and carbon sequestration capacity of forest ecosystem were comprehensively examined based on the review of the latest literatures. The influences of land use change on forest carbon sequestration were analyzed, and factors that leading to the uncertainty of carbon sequestration assessment in forest ecosystem were also discussed. It was estimated that the current forest carbon stock was in the range of 652 to 927 Pg C and the carbon sequestration capacity was approximately 4.02 Pg C · a(-1). In terms of zonal climate, the carbon stock and carbon sequestration capacity of tropical forest were the maximum, about 471 Pg C and 1.02-1.3 Pg C · a(-1) respectively; then the carbon stock of boreal forest was about 272 Pg C, while its carbon sequestration capacity was the minimum, approximately 0.5 Pg C · a(-1); for temperate forest, the carbon stock was minimal, around 113 to 159 Pg C and its carbon sequestration capacity was 0.8 Pg C · a(-1). From the aspect of geographical distribution, the carbon stock of forest ecosystem in South America was the largest (187.7-290 Pg C), then followed by European (162.6 Pg C), North America (106.7 Pg C), Africa (98.2 Pg C) and Asia (74.5 Pg C), and Oceania (21.7 Pg C). In addition, carbon sequestration capacity of regional forest ecosystem was summed up as listed below: Tropical South America forest was the maximum (1276 Tg C · a(-1)), then were Tropical Africa (753 Tg C · a(-1)), North America (248 Tg C · a(-1)) and European (239 Tg C · a(-1)), and East Asia (98.8-136.5 Tg C · a(-1)) was minimum. To further reduce the uncertainty in the estimations of the carbon stock and carbon sequestration capacity of forest ecosystem, comprehensive application of long-term observation, inventories, remote sensing and modeling method should be required.
Computational model of precision grip in Parkinson's disease: a utility based approach
Gupta, Ankur; Balasubramani, Pragathi P.; Chakravarthy, V. Srinivasa
2013-01-01
We propose a computational model of Precision Grip (PG) performance in normal subjects and Parkinson's Disease (PD) patients. Prior studies on grip force generation in PD patients show an increase in grip force during ON medication and an increase in the variability of the grip force during OFF medication (Ingvarsson et al., 1997; Fellows et al., 1998). Changes in grip force generation in dopamine-deficient PD conditions strongly suggest contribution of the Basal Ganglia, a deep brain system having a crucial role in translating dopamine signals to decision making. The present approach is to treat the problem of modeling grip force generation as a problem of action selection, which is one of the key functions of the Basal Ganglia. The model consists of two components: (1) the sensory-motor loop component, and (2) the Basal Ganglia component. The sensory-motor loop component converts a reference position and a reference grip force, into lift force and grip force profiles, respectively. These two forces cooperate in grip-lifting a load. The sensory-motor loop component also includes a plant model that represents the interaction between two fingers involved in PG, and the object to be lifted. The Basal Ganglia component is modeled using Reinforcement Learning with the significant difference that the action selection is performed using utility distribution instead of using purely Value-based distribution, thereby incorporating risk-based decision making. The proposed model is able to account for the PG results from normal and PD patients accurately (Ingvarsson et al., 1997; Fellows et al., 1998). To our knowledge the model is the first model of PG in PD conditions. PMID:24348373
Stengel, James R; Dixon, Andrea L; Allen, Chris T
2003-11-01
Procter & Gamble has long been regarded as a major power of the marketing world and a prime training ground for marketers. But in the summer of 2000, with half of P&G's top 15 brands losing market share and employee morale in ruins, company executives realized that the marketing organization was in trouble. Training programs had been dramatically downsized and in some cases eliminated, employees were being fast-tracked up the career ladder without sufficient time to develop and hone their skills, mentoring had all but disappeared, and the marketing career path had lost its prestige. In an attempt to rebuild P&G's marketing strength, James Stengel, the heir apparent to the chief marketing officer position, began working with University of Cincinnati professors Chris Allen and Andrea Dixon on a new training program to fix the weaknesses in the marketing organization. But when the two professors began interviewing P&G senior executives, they discovered that the plans in motion for mapping out the marketing group's recovery were based not on data but on the intuition of a few individuals at corporate headquarters. So began the most comprehensive internal research endeavor in P&G marketing's history. Using the company's existing process for consumer research, Allen and Dixon shadowed employees, conducted one-on-one interviews, held focus-group sessions, and surveyed 3,500 members of the marketing staff to learn what the company was doing right--and wrong--and what mattered most to its people. The results led to the most sweeping redesign of P&G's marketing organization in 60 years. In this article, the authors explore the value of listening to employees--and truly hearing them. One of their conclusions: A structured research process can show you what's really on employees' minds.
Labrosse, Michel R; Jafar, Reza; Ngu, Janet; Boodhwani, Munir
2016-11-01
Aortic valve (AV) repair has become an attractive option to correct aortic insufficiency. Yet, cusp reconstruction with various cusp replacement materials has been associated with greater long-term repair failures, and it is still unknown how such materials mechanically compare with native leaflets. We used planar biaxial testing to characterize six clinically relevant cusp replacement materials, along with native porcine AV leaflets, to ascertain which materials would be best suited for valve repair. We tested at least six samples of: 1) fresh autologous porcine pericardium (APP), 2) glutaraldehyde fixed porcine pericardium (GPP), 3) St Jude Medical pericardial patch (SJM), 4) CardioCel patch (CC), 5) PeriGuard (PG), 6) Supple PeriGuard (SPG) and 7) fresh porcine AV leaflets (PC). We introduced efficient displacement-controlled testing protocols and processing, as well as advanced convexity requirements on the strain energy functions used to describe the mechanical response of the materials under loading. The proposed experimental and data processing pipeline allowed for a robust in-plane characterization of all the materials tested, with constants determined for two Fung-like hyperelastic, anisotropic strain energy models. Overall, CC and SPG (respectively PG) patches ranked as the closest mechanical equivalents to young (respectively aged) AV leaflets. Because the native leaflets as well as CC, PG and SPG patches exhibit significant anisotropic behaviors, it is suggested that the fiber and cross-fiber directions of these replacement biomaterials be matched with those of the host AV leaflets. The long-term performance of cusp replacement materials would ideally be evaluated in large animal models for AV disease and cusp repair, and over several months or more. Given the unavailability and impracticality of such models, detailed information on stress-strain behavior, as studied herein, and investigations of durability and valve dynamics will be the best surrogates, as they have been for prosthetic valves. Overall, comparison with Fig. 3 suggests that CC and SPG (respectively PG) patches may be the closest mechanical equivalents to young (respectively aged) AV leaflets. Interestingly, the thicknesses of these materials are close to those reported for porcine and younger human AV leaflets, which may facilitate surgical implantation, by contrast to the thinner APP which has poor handling qualities. Because the native leaflets as well as CC, PG and SPG patches exhibit anisotropic behaviors, from a mechanistic perspective alone, it stands to reason that cardiac surgeons should seek to intraoperatively match the fiber and cross-fiber directions of these replacement biomaterials with those of the repaired AV leaflets. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Paclitaxel loaded phospholipid-based gel as a drug delivery system for local treatment of glioma.
Chen, Tijia; Gong, Ting; Zhao, Ting; Liu, Xing; Fu, Yao; Zhang, Zhirong; Gong, Tao
2017-08-07
Paclitaxel (PTX) is a chemotherapeutic agent and has been widely used in clinic against human cancer. However, it has limited application in brain tumor treatment due to the poor penetration of blood brain barrier. Local delivery system is a promising carrier of PTX in the treatment of glioma. A biodegradable phospholipid-based gel (PG) system was developed for intratumoral injection and evaluated in brain glioma-bearing mice model. PTX loaded PG was composed of phospholipid, ethanol, medium chain triglyceride, triacetin and PTX. It was prepared by a very simple method. The system was a transparent solution with good fluidity, while turned into a gel after phase-transition when ethanol diffused. Both in vitro dissolution and in vivo imaging study proved the sustained release effect of PG system. In vivo tolerability study showed a better tolerability after mice treated with PTX PG compared with free PTX. The survival time of brain glioma-bearing mice after treatment with PTX PG was significantly prolonged compared with mice treated by free PTX (P<0.05). In conclusion, this study developed a novel PG based local PTX delivery system with simple preparation method, good tolerability and high therapeutic efficacy. It has a great potential to improve the clinical management of glioma. Copyright © 2017 Elsevier B.V. All rights reserved.
Chai, Hann-Juang; Kiew, Lik-Voon; Chin, Yunni; Norazit, Anwar; Mohd Noor, Suzita; Lo, Yoke-Lin; Looi, Chung-Yeng; Lau, Yeh-Siang; Lim, Tuck-Meng; Wong, Won-Fen; Abdullah, Nor Azizan; Abdul Sattar, Munavvar Zubaid; Johns, Edward J; Chik, Zamri; Chung, Lip-Yong
2017-01-01
Poly-l-glutamic acid (PG) has been used widely as a carrier to deliver anticancer chemotherapeutics. This study evaluates PG as a selective renal drug carrier. 3 H-deoxycytidine-labeled PGs (17 or 41 kDa) and 3 H-deoxycytidine were administered intravenously to normal rats and streptozotocin-induced diabetic rats. The biodistribution of these compounds was determined over 24 h. Accumulation of PG in normal kidneys was also tracked using 5-(aminoacetamido) fluorescein (fluoresceinyl glycine amide)-labeled PG (PG-AF). To evaluate the potential of PGs in ferrying renal protective anti-oxidative stress compounds, the model drug 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF) was conjugated to 41 kDa PG to form PG-AEBSF. PG-AEBSF was then characterized and evaluated for intracellular anti-oxidative stress efficacy (relative to free AEBSF). In the normal rat kidneys, 17 kDa radiolabeled PG (PG-Tr) presents a 7-fold higher, while 41 kDa PG-Tr shows a 15-fold higher renal accumulation than the free radiolabel after 24 h post injection. The accumulation of PG-AF was primarily found in the renal tubular tissues at 2 and 6 h after an intravenous administration. In the diabetic (oxidative stress-induced) kidneys, 41 kDa PG-Tr showed the greatest renal accumulation of 8-fold higher than the free compound 24 h post dose. Meanwhile, the synthesized PG-AEBSF was found to inhibit intracellular nicotinamide adenine dinucleotide phosphate oxidase (a reactive oxygen species generator) at an efficiency that is comparable to that of free AEBSF. This indicates the preservation of the anti-oxidative stress properties of AEBSF in the conjugated state. The favorable accumulation property of 41 kDa PG in normal and oxidative stress-induced kidneys, along with its capabilities in conserving the pharmacological properties of the conjugated renal protective drugs, supports its role as a potential renal targeting drug carrier.
Chai, Hann-Juang; Kiew, Lik-Voon; Chin, Yunni; Norazit, Anwar; Mohd Noor, Suzita; Lo, Yoke-Lin; Looi, Chung-Yeng; Lau, Yeh-Siang; Lim, Tuck-Meng; Wong, Won-Fen; Abdullah, Nor Azizan; Abdul Sattar, Munavvar Zubaid; Johns, Edward J; Chik, Zamri; Chung, Lip-Yong
2017-01-01
Background and purpose Poly-l-glutamic acid (PG) has been used widely as a carrier to deliver anticancer chemotherapeutics. This study evaluates PG as a selective renal drug carrier. Experimental approach 3H-deoxycytidine-labeled PGs (17 or 41 kDa) and 3H-deoxycytidine were administered intravenously to normal rats and streptozotocin-induced diabetic rats. The biodistribution of these compounds was determined over 24 h. Accumulation of PG in normal kidneys was also tracked using 5-(aminoacetamido) fluorescein (fluoresceinyl glycine amide)-labeled PG (PG-AF). To evaluate the potential of PGs in ferrying renal protective anti-oxidative stress compounds, the model drug 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF) was conjugated to 41 kDa PG to form PG-AEBSF. PG-AEBSF was then characterized and evaluated for intracellular anti-oxidative stress efficacy (relative to free AEBSF). Results In the normal rat kidneys, 17 kDa radiolabeled PG (PG-Tr) presents a 7-fold higher, while 41 kDa PG-Tr shows a 15-fold higher renal accumulation than the free radiolabel after 24 h post injection. The accumulation of PG-AF was primarily found in the renal tubular tissues at 2 and 6 h after an intravenous administration. In the diabetic (oxidative stress-induced) kidneys, 41 kDa PG-Tr showed the greatest renal accumulation of 8-fold higher than the free compound 24 h post dose. Meanwhile, the synthesized PG-AEBSF was found to inhibit intracellular nicotinamide adenine dinucleotide phosphate oxidase (a reactive oxygen species generator) at an efficiency that is comparable to that of free AEBSF. This indicates the preservation of the anti-oxidative stress properties of AEBSF in the conjugated state. Conclusion/Implications The favorable accumulation property of 41 kDa PG in normal and oxidative stress-induced kidneys, along with its capabilities in conserving the pharmacological properties of the conjugated renal protective drugs, supports its role as a potential renal targeting drug carrier. PMID:28144140
Sun, Jianxia; Mei, Zhouxiong; Tang, Yajuan; Ding, Lijun; Jiang, Guichuan; Zhang, Chi; Sun, Aidong; Bai, Weibin
2016-08-24
As an alternative preservation method to thermal treatment, ultrasound is a novel non-thermal processing technology that can significantly avoid undesirable nutritional changes. However, recently literature indicated that anthocyanin degradation occurred when high amplitude ultrasound was applied to juice. This work mainly studied the effect of ultrasound on the stability and antioxidant capacity of pelargonidin-3-glucoside (Pg-3-glu) and the correlation between anthocyanin degradation and •OH generation in a simulated system. Results indicated that the spectral intensities of Pg-3-glu decreased with increasing ultrasound power (200-500 W) and treatment time (0-60 min). The degradation trend was consistent with first-order reaction kinetics (R² > 0.9100). Further study showed that there was a good linear correlation between Pg-3-glu degradation and •OH production (R² = 0.8790), which indicated the important role of •OH in the degradation of anthocyanin during ultrasound exposure. Moreover, a decrease in the antioxidant activity of solution(s) containing Pg-3-glu as evaluated by the DPPH and FRAP methods was observed after ultrasound treatment.
Fire dynamics during the 20th century simulated by the Community Land Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kloster, Silvia; Mahowald, Natalie; Randerson, Jim
2011-01-01
Fire is an integral Earth System process that interacts with climate in multiple ways. Here we assessed the parametrization of fires in the Community Land Model (CLM-CN) and improved the ability of the model to reproduce contemporary global patterns of burned areas and fire emissions. In addition to wildfires we extended CLM-CN to account for fires related to deforestation. We compared contemporary fire carbon emissions predicted by the model to satellite-based estimates in terms of magnitude and spatial extent as well as interannual and seasonal variability. Long-term trends during the 20th century were compared with historical estimates. Overall we foundmore » the best agreement between simulation and observations for the fire parametrization based on the work by Arora and Boer (2005). We obtained substantial improvement when we explicitly considered human caused ignition and fire suppression as a function of population density. Simulated fire carbon emissions ranged between 2.0 and 2.4 Pg C/year for the period 1997 2004. Regionally the simulations had a low bias over Africa and a high bias over South America when compared to satellite-based products. The net terrestrial carbon source due to land use change for the 1990s was 1.2 Pg C/year with 11% stemming from deforestation fires. During 2000 2004 this flux decreased to 0.85 Pg C/year with a similar relative contribution from deforestation fires. Between 1900 and 1960 we predicted a slight downward trend in global fire emissions caused by reduced fuels as a consequence of wood harvesting and also by increases in fire suppression. The model predicted an upward trend during the last three decades of the 20th century as a result of climate variations and large burning events associated with ENSO-induced drought conditions.« less
Membrane selectivity and disordering mechanism of antimicrobial peptide protegrin-1
NASA Astrophysics Data System (ADS)
Ishitsuka, Yuji
Protegrin-1 (PG-1) is a beta-sheet antimicrobial peptide (AMP), a class of peptides innate to various organisms and functions as a defense agent against harmful microorganisms by means of membrane disordering. Characteristic chemical and structural properties of AMPs allow selective interaction against invaders' cell membranes. Despite their enormous biomedical potential, progress towards developing them into therapeutic agents has been hampered by a lack of insight into their mechanism of action. AMP insertion assays using Langmuir monolayers reveal that both electrostatic properties of the lipid head group as well as the packing density of the lipid tail group play important roles in determining the membrane selectivity of AMPs. These results help elucidate how the AMP selectively targets the cell membrane of microorganisms over the cell membrane of the host. In addition, these results also explain the higher hemolytic ability of PG-1 against human red blood cells (RBCs) compared to the hemolytic ability of PG-1 against sheep and pig RBCs. Synchrotron X-ray reflectivity shows that PG-1 penetrates into the lipid layer. Grazing incidence X-ray diffraction and fluorescence microscopy indicate that the insertion of PG-1 disorders tail group packing. Membrane selectivity and insertion location information of AMPs with different primary sequence and secondary structure have been obtained by using a truncated version of PG-1: PC-17, and an alpha-helical AMP, LL-37, respectively. The similarity of the membrane disordering process across these various peptides motivated us to test the membrane disordering effect of molecules designed to mimic these peptides. Peptide-mimics based on meta-phenylene ethynylenes demonstrate similar membrane disordering effects, showing that the potency of AMPs is derived from their overall chemical and structural properties, rather than exact peptide sequence. Atomic force microscopy (AFM) was used to directly image first, the PG-1 concentration-dependent membrane thinning effect, and second, the PG-1-induced structural transformation of a contiguous supported bilayer patch into a porous one. Our results point the membrane disordering mechanism of PG-1 towards the carpet/toroidal model of membrane disordering. Ongoing AMP-related projects are also discussed.
Proctor and gamble technology process assessment for bioenergy production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, Hongqiang; Boardman, Richard Doin; Wright, Christopher Todd
P&G intends to replace as much as their current heat and power by renewable energy sources. For 2014, P&G’s total energy including electricity, natural gas and steam is approximately 1,540,000 MMBTU annually (Table 2). The biomass and wastes around P&G facility can be grouped into six categories (Figure 6): (1) Agriculture residue and grass, (2) Refuse (inorganic) solid material, (3) Food waste, (4) Organic waste stream, (5) livestock manure, (6) wastewater and sludge. The six feedstock sources can provide a total energy of 3,520,000 MMBTU per year (Table 10), among which the agriculture residue is the biggest fraction, about 67%,more » followed by livestock manures 27%. Therefore, the available energy sources around P&G facility are enough to meet their energy needs. These energy feedstocks would be treated by two processes: anaerobic digestion for biogas subsequently for heat and power and thermochemical process (combustion, pyrolysis and gasification) for heat and power (Figure 8 and 9). For AD, a one-stage complete mixing digester is preferable; and fluidized bed reactors are favorable for thermochemical process.« less
Vazir, Shahnaz; Engle, Patrice; Balakrishna, Nagalla; Griffiths, Paula L; Johnson, Susan L; Creed-Kanashiro, Hilary; Fernandez Rao, Sylvia; Shroff, Monal R; Bentley, Margaret E
2013-01-01
Inadequate feeding and care may contribute to high rates of stunting and underweight among children in rural families in India. This cluster-randomized trial tested the hypothesis that teaching caregivers appropriate complementary feeding and strategies for how to feed and play responsively through home-visits would increase children's dietary intake, growth and development compared with home-visit-complementary feeding education alone or routine care. Sixty villages in Andhra Pradesh were randomized into three groups of 20 villages with 200 mother-infant dyads in each group. The control group (CG) received routine Integrated Child Development Services (ICDS); the complementary feeding group (CFG) received the ICDS plus the World Health Organization recommendations on breastfeeding and complementary foods; and the responsive complementary feeding and play group (RCF&PG) received the same intervention as the CFG plus skills for responsive feeding and psychosocial stimulation. Both intervention groups received bi-weekly visits by trained village women. The groups did not differ at 3 months on socioeconomic status, maternal and child nutritional indices, and maternal depression. After controlling for potential confounding factors using the mixed models approach, the 12-month intervention to the CFG and RCF&PG significantly (P < 0.05) increased median intakes of energy, protein, Vitamin A, calcium (CFG), iron and zinc, reduced stunting [0.19, confidence interval (CI): 0.0-0.4] in the CFG (but not RCF&PG) and increased (P < 0.01) Bayley Mental Development scores (mean = 3.1, CI: 0.8-5.3) in the RCF&PG (but not CFG) compared with CG. Community-based educational interventions can improve dietary intake, length (CFG) and mental development (RCF&PG) for children under 2 years in food-secure rural Indian families. © 2012 Blackwell Publishing Ltd.
Biodegradation of propylene glycol and associated hydrodynamic effects in sand.
Bielefeldt, Angela R; Illangasekare, Tissa; Uttecht, Megan; LaPlante, Rosanna
2002-04-01
At airports around the world, propylene glycol (PG) based fluids are used to de-ice aircraft for safe operation. PG removal was investigated in 15-cm deep saturated sand columns. Greater than 99% PG biodegradation was achieved for all flow rates and loading conditions tested, which decreased the hydraulic conductivity of the sand by 1-3 orders of magnitude until a steady-state minimum was reached. Under constant loading at 120 mg PG/d for 15-30 d, the hydraulic conductivity (K) decreased by 2-2.5 orders of magnitude when the average linear velocity of the water was 4.9-1.4 cm/h. Variable PG loading in recirculation tests resulted in slower conductivity declines and lower final steady-state conductivity than constant PG feeding. After significant sand plugging, endogenous periods of time without PG resulted in significant but partial recovery of the original conductivity. Biomass growth also increased the dispersivity of the sand.
Probability of identification: adulteration of American Ginseng with Asian Ginseng.
Harnly, James; Chen, Pei; Harrington, Peter De B
2013-01-01
The AOAC INTERNATIONAL guidelines for validation of botanical identification methods were applied to the detection of Asian Ginseng [Panax ginseng (PG)] as an adulterant for American Ginseng [P. quinquefolius (PQ)] using spectral fingerprints obtained by flow injection mass spectrometry (FIMS). Samples of 100% PQ and 100% PG were physically mixed to provide 90, 80, and 50% PQ. The multivariate FIMS fingerprint data were analyzed using soft independent modeling of class analogy (SIMCA) based on 100% PQ. The Q statistic, a measure of the degree of non-fit of the test samples with the calibration model, was used as the analytical parameter. FIMS was able to discriminate between 100% PQ and 100% PG, and between 100% PQ and 90, 80, and 50% PQ. The probability of identification (POI) curve was estimated based on the SD of 90% PQ. A digital model of adulteration, obtained by mathematically summing the experimentally acquired spectra of 100% PQ and 100% PG in the desired ratios, agreed well with the physical data and provided an easy and more accurate method for constructing the POI curve. Two chemometric modeling methods, SIMCA and fuzzy optimal associative memories, and two classification methods, partial least squares-discriminant analysis and fuzzy rule-building expert systems, were applied to the data. The modeling methods correctly identified the adulterated samples; the classification methods did not.
A comparative density functional study on electrical properties of layered penta-graphene
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, Zhi Gen, E-mail: yuzg@ihpc.a-star.edu.sg; Zhang, Yong-Wei, E-mail: zhangyw@ihpc.a-star.edu.sg
We present a comparative study of the influence of the number of layers, the biaxial strain in the range of −3% to 3%, and the stacking misalignments on the electronic properties of a new 2D carbon allotrope, penta-graphene (PG), based on hybrid-functional method within the density functional theory (DFT). In comparison with local exchange-correlation approximation in the DFT, the hybrid-functional provides an accurate description on the degree of p{sub z} orbitals localization and bandgap. Importantly, the predicted bandgap of few-layer PG has a weak layer dependence. The bandgap of monolayer PG is 3.27 eV, approximately equal to those of GaN andmore » ZnO; and the bandgap of few-layer PG decreases slowly with the number of layers (N) and converge to 2.57 eV when N ≥ 4. Our calculations using HSE06 functional on few-layer PG reveal that bandgap engineering by stacking misalignment can further tune the bandgap down to 1.37 eV. Importantly, there is no direct-to-indirect bandgap transition in PG by varying strain, layer number, and stacking misalignment. Owing to its tunable, robustly direct, and wide bandgap characteristics, few-layer PG is promising for optoelectronic and photovoltaic applications.« less
Zhuang, Q.; McGuire, A.D.; Melillo, J.M.; Clein, Joy S.; Dargaville, R.J.; Kicklighter, D.W.; Myneni, Ranga B.; Dong, J.; Romanovsky, V.E.; Harden, J.; Hobbie, J.E.
2003-01-01
There is substantial evidence that soil thermal dynamics are changing in terrestrial ecosystems of the Northern Hemisphere and that these dynamics have implications for the exchange of carbon between terrestrial ecosystems and the atmosphere. To date, large-scale biogeochemical models have been slow to incorporate the effects of soil thermal dynamics on processes that affect carbon exchange with the atmosphere. In this study we incorporated a soil thermal module (STM), appropriate to both permafrost and non-permafrost soils, into a large-scale ecosystem model, version 5.0 of the Terrestrial Ecosystem Model (TEM). We then compared observed regional and seasonal patterns of atmospheric CO2 to simulations of carbon dynamics for terrestrial ecosystems north of 30°N between TEM 5.0 and an earlier version of TEM (version 4.2) that lacked a STM. The timing of the draw-down of atmospheric CO2 at the start of the growing season and the degree of draw-down during the growing season were substantially improved by the consideration of soil thermal dynamics. Both versions of TEM indicate that climate variability and change promoted the loss of carbon from temperate ecosystems during the first half of the 20th century, and promoted carbon storage during the second half of the century. The results of the simulations by TEM suggest that land-use change in temperate latitudes (30–60°N) plays a stronger role than climate change in driving trends for increased uptake of carbon in extratropical terrestrial ecosystems (30–90°N) during recent decades. In the 1980s the TEM 5.0 simulation estimated that extratropical terrestrial ecosystems stored 0.55 Pg C yr−1, with 0.24 Pg C yr−1 in North America and 0.31 Pg C yr−1 in northern Eurasia. From 1990 through 1995 the model simulated that these ecosystems stored 0.90 Pg C yr−1, with 0.27 Pg C yr−1 stored in North America and 0.63 Pg C yr−1 stored in northern Eurasia. Thus, in comparison to the 1980s, simulated net carbon storage in the 1990s was enhanced by an additional 0.35 Pg C yr−1 in extratropical terrestrial ecosystems, with most of the additional storage in northern Eurasia. The carbon storage simulated by TEM 5.0 in the 1980s and 1990s was lower than estimates based on other methodologies, including estimates by atmospheric inversion models and remote sensing and inventory analyses. This suggests that other issues besides the role of soil thermal dynamics may be responsible, in part, for the temporal and spatial dynamics of carbon storage of extratropical terrestrial ecosystems. In conclusion, the consideration of soil thermal dynamics and terrestrial cryospheric processes in modeling the global carbon cycle has helped to reduce biases in the simulation of the seasonality of carbon dynamics of extratropical terrestrial ecosystems. This progress should lead to an enhanced ability to clarify the role of other issues that influence carbon dynamics in terrestrial regions that experience seasonal freezing and thawing of soil.
Carbon stock and its responses to climate change in Central Asia.
Li, Chaofan; Zhang, Chi; Luo, Geping; Chen, Xi; Maisupova, Bagila; Madaminov, Abdullo A; Han, Qifei; Djenbaev, Bekmamat M
2015-05-01
Central Asia has a land area of 5.6 × 10(6) km(2) and contains 80-90% of the world's temperate deserts. Yet it is one of the least characterized areas in the estimation of the global carbon (C) stock/balance. This study assessed the sizes and spatiotemporal patterns of C pools in Central Asia using both inventory (based on 353 biomass and 284 soil samples) and process-based modeling approaches. The results showed that the C stock in Central Asia was 31.34-34.16 Pg in the top 1-m soil with another 10.42-11.43 Pg stored in deep soil (1-3 m) of the temperate deserts. They amounted to 18-24% of the global C stock in deserts and dry shrublands. The C stock was comparable to that of the neighboring regions in Eurasia or major drylands around the world (e.g. Australia). However, 90% of Central Asia C pool was stored in soil, and the fraction was much higher than in other regions. Compared to hot deserts of the world, the temperate deserts in Central Asia had relatively high soil organic carbon density. The C stock in Central Asia is under threat from dramatic climate change. During a decadal drought between 1998 and 2008, which was possibly related to protracted La Niña episodes, the dryland lost approximately 0.46 Pg C from 1979 to 2011. The largest C losses were found in northern Kazakhstan, where annual precipitation declined at a rate of 90 mm decade(-1) . The regional C dynamics were mainly determined by changes in the vegetation C pool, and the SOC pool was stable due to the balance between reduced plant-derived C influx and inhibited respiration. © 2015 John Wiley & Sons Ltd.
Analysis of anabolic steroids in human hair using LC-MS/MS.
Deshmukh, Nawed; Hussain, Iltaf; Barker, James; Petroczi, Andrea; Naughton, Declan P
2010-10-01
New highly sensitive, specific, reliable, reproducible and robust LC-MS/MS methods were developed to detect the anabolic steroids, nandrolone and stanozolol, in human hair for the first time. Hair samples from 180 participants (108 males, 72 females, 62% athletes) were screened using ELISA which revealed 16 athletes as positive for stanozolol and 3 for nandrolone. Positive samples were confirmed on LC-MS/MS in selective reaction monitoring (SRM) mode. The assays for stanozolol and nandrolone showed good linearity in the range 1-400pg/mg and 5-400pg/mg, respectively. The methods were validated for LLOD, interday precision, intraday precision, specificity, extraction recovery and accuracy. The assays were capable of detecting 0.5pg stanozolol and 3.0pg nandrolone per mg of hair, when approximately 20mg of hair were processed. Analysis using LC-MS/MS confirmed 11 athletes' positive for stanozolol (5.0pg/mg to 86.3pg/mg) and 1 for nandrolone (14.0pg/mg) thus avoiding false results from ELISA screening. The results obtained demonstrate the application of these hair analysis methods to detect both steroids at low concentrations, hence reducing the amount of hair required significantly. The new methods complement urinalysis or blood testing and facilitate improved doping testing regimes. Hair analysis benefits from non-invasiveness, negligible risk of infection and facile sample storage and collection, whilst reducing risks of tampering and cross-contamination. Owing to the wide detection window, this approach may also offer an alternative approach for out-of-competition testing.
NASA Astrophysics Data System (ADS)
Moteabbed, M.; España, S.; Paganetti, H.
2011-02-01
The purpose of this work was to compare the clinical adaptation of prompt gamma (PG) imaging and positron emission tomography (PET) as independent tools for non-invasive proton beam range verification and treatment validation. The PG range correlation and its differences with PET have been modeled for the first time in a highly heterogeneous tissue environment, using different field sizes and configurations. Four patients with different tumor locations (head and neck, prostate, spine and abdomen) were chosen to compare the site-specific behaviors of the PG and PET images, using both passive scattered and pencil beam fields. Accurate reconstruction of dose, PG and PET distributions was achieved by using the planning computed tomography (CT) image in a validated GEANT4-based Monte Carlo code capable of modeling the treatment nozzle and patient anatomy in detail. The physical and biological washout phenomenon and decay half-lives for PET activity for the most abundant isotopes such as 11C, 15O, 13N, 30P and 38K were taken into account in the data analysis. The attenuation of the gamma signal after traversing the patient geometry and respective detection efficiencies were estimated for both methods to ensure proper comparison. The projected dose, PG and PET profiles along many lines in the beam direction were analyzed to investigate the correlation consistency across the beam width. For all subjects, the PG method showed on average approximately 10 times higher gamma production rates than the PET method before, and 60 to 80 times higher production after including the washout correction and acquisition time delay. This rate strongly depended on tissue density and elemental composition. For broad passive scattered fields, it was demonstrated that large differences exist between PG and PET signal falloff positions and the correlation with the dose distribution for different lines in the beam direction. These variations also depended on the treatment site and the particular subject. Thus, similar to PET, direct range verification with PG in passive scattering is not easily viable. However, upon development of an optimized 3D PG detector, indirect range verification by comparing measured and simulated PG distributions (currently being explored for the PET method) would be more beneficial because it can avoid the inherent biological challenges of the PET imaging. The improved correlation of PG and PET with dose when using pencil beams was evident. PG imaging was found to be potentially advantageous especially for small tumors in the presence of high tissue heterogeneities. Including the effects of detector acceptance and efficiency may hold PET superior in terms of the amplitude of the detected signal (depending on the future development of PG detection technology), but the ability to perform online measurements and avoid signal disintegration (due to washout) with PG are important factors that can outweigh the benefits of higher detection sensitivity.
Moteabbed, M; España, S; Paganetti, H
2011-02-21
The purpose of this work was to compare the clinical adaptation of prompt gamma (PG) imaging and positron emission tomography (PET) as independent tools for non-invasive proton beam range verification and treatment validation. The PG range correlation and its differences with PET have been modeled for the first time in a highly heterogeneous tissue environment, using different field sizes and configurations. Four patients with different tumor locations (head and neck, prostate, spine and abdomen) were chosen to compare the site-specific behaviors of the PG and PET images, using both passive scattered and pencil beam fields. Accurate reconstruction of dose, PG and PET distributions was achieved by using the planning computed tomography (CT) image in a validated GEANT4-based Monte Carlo code capable of modeling the treatment nozzle and patient anatomy in detail. The physical and biological washout phenomenon and decay half-lives for PET activity for the most abundant isotopes such as (11)C, (15)O, (13)N, (30)P and (38)K were taken into account in the data analysis. The attenuation of the gamma signal after traversing the patient geometry and respective detection efficiencies were estimated for both methods to ensure proper comparison. The projected dose, PG and PET profiles along many lines in the beam direction were analyzed to investigate the correlation consistency across the beam width. For all subjects, the PG method showed on average approximately 10 times higher gamma production rates than the PET method before, and 60 to 80 times higher production after including the washout correction and acquisition time delay. This rate strongly depended on tissue density and elemental composition. For broad passive scattered fields, it was demonstrated that large differences exist between PG and PET signal falloff positions and the correlation with the dose distribution for different lines in the beam direction. These variations also depended on the treatment site and the particular subject. Thus, similar to PET, direct range verification with PG in passive scattering is not easily viable. However, upon development of an optimized 3D PG detector, indirect range verification by comparing measured and simulated PG distributions (currently being explored for the PET method) would be more beneficial because it can avoid the inherent biological challenges of the PET imaging. The improved correlation of PG and PET with dose when using pencil beams was evident. PG imaging was found to be potentially advantageous especially for small tumors in the presence of high tissue heterogeneities. Including the effects of detector acceptance and efficiency may hold PET superior in terms of the amplitude of the detected signal (depending on the future development of PG detection technology), but the ability to perform online measurements and avoid signal disintegration (due to washout) with PG are important factors that can outweigh the benefits of higher detection sensitivity.
Unraveling net carbon exchange into its component processes of photosynthesis and respiration
NASA Astrophysics Data System (ADS)
Ballantyne, A.
2017-12-01
The recent `warming hiatus' presents an excellent opportunity to investigate climate sensitivity of carbon cycle processes. Herewe combine satellite and atmospheric observations to show that the rate of net biome productivity (NBP) has significantlyaccelerated from 0.007+/-0.065 PgC yr-2 over the warming period (1982 to 1998) to 0.119+/-0.071 PgC yr-2 over thewarminghiatus (1998-2012). This acceleration in NBP is not due to increased primary productivity, but rather reduced respiration thatis correlated (r2 0.58; P = 0.0007) and sensitive ( gamma= 4.05 to 9.40 PgC yr-1 per deg C) to land temperatures. Global landmodels do not fully capture this apparent reduced respiration over the warming hiatus; however, an empirical model includingsoil temperature and moisture observations seems to better captures the reduced respiration.
NASA Astrophysics Data System (ADS)
Wang, J.; Zeng, N.; Wang, M. R.
2015-12-01
The interannual variability (IAV) in atmospheric CO2 growth rate (CGR) is closely connected with the El Niño-Southern Oscillation. However, sensitivities of CGR to temperature and precipitation remain largely uncertain. This paper analyzed the relationship between Mauna Loa CGR and tropical land climatic elements. We find that Mauna Loa CGR lags precipitation by 4 months with a correlation coefficient of -0.63, leads temperature by 1 month (0.77), and correlates with soil moisture (-0.65) with zero lag. Additionally, precipitation and temperature are highly correlated (-0.66), with precipitation leading by 4-5 months. Regression analysis shows that sensitivities of Mauna Loa CGR to temperature and precipitation are 2.92 ± 0.20 Pg C yr-1 K-1 and -0.46 ± 0.07 Pg C yr-1 100 mm-1, respectively. Unlike some recent suggestions, these empirical relationships favor neither temperature nor precipitation as the dominant factor of CGR IAV. We further analyzed seven terrestrial carbon cycle models, from the TRENDY project, to study the processes underlying CGR IAV. All models capture well the IAV of tropical land-atmosphere carbon flux (CFTA). Sensitivities of the ensemble mean CFTA to temperature and precipitation are 3.18 ± 0.11 Pg C yr-1 K-1 and -0.67 ± 0.04 Pg C yr-1 100 mm-1, close to Mauna Loa CGR. Importantly, the models consistently show the variability in net primary productivity (NPP) dominates CGR, rather than soil respiration. Because NPP is largely driven by precipitation, this suggests a key role of precipitation in CGR IAV despite the higher CGR correlation with temperature. Understanding the relative contribution of CO2 sensitivity to precipitation and temperature has important implications for future carbon-climate feedback using such "emergent constraint".
Combined constraints on global ocean primary production using observations and models
NASA Astrophysics Data System (ADS)
Buitenhuis, Erik T.; Hashioka, Taketo; Quéré, Corinne Le
2013-09-01
production is at the base of the marine food web and plays a central role for global biogeochemical cycles. Yet global ocean primary production is known to only a factor of 2, with previous estimates ranging from 38 to 65 Pg C yr-1 and no formal uncertainty analysis. Here, we present an improved global ocean biogeochemistry model that includes a mechanistic representation of photosynthesis and a new observational database of net primary production (NPP) in the ocean. We combine the model and observations to constrain particulate NPP in the ocean with statistical metrics. The PlankTOM5.3 model includes a new photosynthesis formulation with a dynamic representation of iron-light colimitation, which leads to a considerable improvement of the interannual variability of surface chlorophyll. The database includes a consistent set of 50,050 measurements of 14C primary production. The model best reproduces observations when global NPP is 58 ± 7 Pg C yr-1, with a most probable value of 56 Pg C yr-1. The most probable value is robust to the model used. The uncertainty represents 95% confidence intervals. It considers all random errors in the model and observations, but not potential biases in the observations. We show that tropical regions (23°S-23°N) contribute half of the global NPP, while NPPs in the Northern and Southern Hemispheres are approximately equal in spite of the larger ocean area in the South.
Mertens, Jeffrey A; Bowman, Michael J
2011-04-01
Polygalacturonase (PG) enzymes hydrolyze the long polygalacturonic acid chains found in the smooth regions of pectin. Interest in this enzyme class continues due to their ability to macerate tissues of economically important crops and their use in a number of industrial processes. Rhizopus oryzae has a large PG gene family with 15 of 18 genes encoding unique active enzymes. The PG enzymes, 12 endo-PG and 3 exo-galacturonases, were expressed in Pichia pastoris and purified enabling biochemical characterization to gain insight into the maintenance of this large gene family within the Rhizopus genome. The 15 PG enzymes have a pH optima ranging from 4.0 to 5.0. Temperature optima of the 15 PG enzymes vary from 30 to 40 °C. While the pH and temperature optima do little to separate the enzymes, the specific activity of the enzymes is highly variable ranging from over 200 to less than 1 μmol/min/mg. A general pattern related to the groupings found in the phylogentic tree was visible with the group containing the exo-PG enzymes demonstrating the lowest specific activity. Finally, the progress curves of the PG enzymes, contained within the phylogenetic group that includes the exo-PG enzymes, acting on trigalacturonic acid lend additional support to the idea that the ancestral form of PG in Rhizopus is endolytic and exolytic function evolved later.
Nghi, Tran Ngoc; Nishijo, Muneko; Manh, Ho Dung; Tai, Pham The; Van Luong, Hoang; Anh, Tran Hai; Thao, Pham Ngoc; Trung, Nguyen Viet; Waseda, Tomoo; Nakagawa, Hideaki; Kido, Teruhiko; Nishijo, Hisao
2015-05-05
Bien Hoa Air Base is the largest dioxin contamination hot spot in Vietnam. In 2012, we recruited 216 mothers who were living in 10 communities around Bien Hoa Air Base and had delivered newborns at a prefecture hospital, and we investigated recent exposure levels of dioxins and nonortho PCBs in their breast milk. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD) was present at 2.6 pg/g lipid in primiparae and 2.2 pg/g lipid in multiparae. Among multiparae and total subjects, significant high prevalence of 2,3,7,8-tetraCDD≥5 pg/g lipid and 2,3,7,8-tetraCDD contribution≥40% were observed in mothers living in the five communities closest to Bien Hoa Air Base. The TEQ for nonortho PCBs was 1.6 pg-TEQ/g lipid for primiparae, and this was even lower than that in the unsprayed area. The length of residency was a strong factor to increase dioxins, including 2,3,7,8-tetraCDD. Residency in the five communities with the highest exposure was a specific risk factor for increased 2,3,7,8-tetraCDD in breast milk. Food intake might contribute partly to the increased levels of dioxin congeners other than 2,3,7,8-tetraCDD in breast milk. These results suggest that Bien Hoa Air Base has led to elevated 2,3,7,8-tetraCDD levels in breast milk of mothers in nearby areas even in the recent years.
Timm, Kerstin N; Hartl, Johannes; Keller, Markus A; Hu, De-En; Kettunen, Mikko I; Rodrigues, Tiago B; Ralser, Markus; Brindle, Kevin M
2015-12-01
A resonance at ∼181 ppm in the (13) C spectra of tumors injected with hyperpolarized [U-(2) H, U-(13) C]glucose was assigned to 6-phosphogluconate (6PG), as in previous studies in yeast, whereas in breast cancer cells in vitro this resonance was assigned to 3-phosphoglycerate (3PG). These peak assignments were investigated here using measurements of 6PG and 3PG (13) C-labeling using liquid chromatography tandem mass spectrometry (LC-MS/MS) METHODS: Tumor-bearing mice were injected with (13) C6 glucose and the (13) C-labeled and total 6PG and 3PG concentrations measured. (13) C MR spectra of glucose-6-phosphate dehydrogenase deficient (zwf1Δ) and wild-type yeast were acquired following addition of hyperpolarized [U-(2) H, U-(13) C]glucose and again (13) C-labeled and total 6PG and 3PG were measured by LC-MS/MS RESULTS: Tumor (13) C-6PG was more abundant than (13) C-2PG/3PG and the resonance at ∼181 ppm matched more closely that of 6PG. (13) C MR spectra of wild-type and zwf1Δ yeast cells showed a resonance at ∼181 ppm after labeling with hyperpolarized [U-(2) H, U-(13) C]glucose, however, there was no 6PG in zwf1Δ cells. In the wild-type cells 3PG was approximately four-fold more abundant than 6PG CONCLUSION: The resonance at ∼181 ppm in (13) C MR spectra following injection of hyperpolarized [U-(2) H, U-(13) C]glucose originates predominantly from 6PG in EL4 tumors and 3PG in yeast cells. © 2014 Wiley Periodicals, Inc.
Kang, Jing; Han, Lu; Chen, Zhonglin; Shen, Jimin; Nan, Jun; Zhang, Yihua
2014-09-15
In this paper, a novel chemiluminescence (CL) method has been developed for the determination of propyl gallate (PG). The proposed method was based on the enhancing effect of PG on the CL signal of 2-phenyl-4,5-di(2-furyl)-1H-imidazole (PDFI) and K3Fe(CN)6 reaction in an alkaline solution. Under the optimum conditions, the enhanced CL intensity was linearly related to the concentration of PG. The linear range of the calibration curve was 0.05-8 μg/mL, and the corresponding detection limit (3σ) was 0.036 μg/mL. The relative standard deviation for determining 1.0 μg/mL PG was 2.8% (n=11). The proposed method has been successfully applied to the determination of PG in edible oil. The edible oil samples were prepared by the solid-phase extraction (SPE) with a C18 column served as the stationary phase. Furthermore, the possible CL mechanism was also discussed briefly based on the photoluminescence (PL) and CL spectra. Copyright © 2014 Elsevier Ltd. All rights reserved.
Effect of biogenic fermentation impurities on lactic acid hydrogenation to propylene glycol.
Zhang, Zhigang; Jackson, James E; Miller, Dennis J
2008-09-01
The effect of residual impurities from glucose fermentation to lactic acid (LA) on subsequent ruthenium-catalyzed hydrogenation of LA to propylene glycol (PG) is examined. Whereas refined LA feed exhibits stable conversion to PG over carbon-supported ruthenium catalyst in a trickle bed reactor, partially refined LA from fermentation shows a steep decline in PG production over short (<40 h) reaction times followed by a further slow decay in performance. Addition of model impurities to refined LA has varying effects: organic acids, sugars, or inorganic salts have little effect on conversion; alanine, a model amino acid, results in a strong but reversible decline in conversion via competitive adsorption between alanine and LA on the Ru surface. The sulfur-containing amino acids cysteine and methionine irreversibly poison the catalyst for LA conversion. Addition of 0.1 wt% albumin as a model protein leads to slow decline in rate, consistent with pore plugging or combined pore plugging and poisoning of the Ru surface. This study points to the need for integrated design and operation of biological processes and chemical processes in the biorefinery in order to make efficient conversion schemes viable.
Constraining 3-PG with a new δ13C submodel: a test using the δ13C of tree rings.
Wei, Liang; Marshall, John D; Link, Timothy E; Kavanagh, Kathleen L; DU, Enhao; Pangle, Robert E; Gag, Peter J; Ubierna, Nerea
2014-01-01
A semi-mechanistic forest growth model, 3-PG (Physiological Principles Predicting Growth), was extended to calculate δ(13)C in tree rings. The δ(13)C estimates were based on the model's existing description of carbon assimilation and canopy conductance. The model was tested in two ~80-year-old natural stands of Abies grandis (grand fir) in northern Idaho. We used as many independent measurements as possible to parameterize the model. Measured parameters included quantum yield, specific leaf area, soil water content and litterfall rate. Predictions were compared with measurements of transpiration by sap flux, stem biomass, tree diameter growth, leaf area index and δ(13)C. Sensitivity analysis showed that the model's predictions of δ(13)C were sensitive to key parameters controlling carbon assimilation and canopy conductance, which would have allowed it to fail had the model been parameterized or programmed incorrectly. Instead, the simulated δ(13)C of tree rings was no different from measurements (P > 0.05). The δ(13)C submodel provides a convenient means of constraining parameter space and avoiding model artefacts. This δ(13)C test may be applied to any forest growth model that includes realistic simulations of carbon assimilation and transpiration. © 2013 John Wiley & Sons Ltd.
Production of Phloroglucinol, a Platform Chemical, in Arabidopsis using a Bacterial Gene.
Abdel-Ghany, Salah E; Day, Irene; Heuberger, Adam L; Broeckling, Corey D; Reddy, Anireddy S N
2016-12-07
Phloroglucinol (1,3,5-trihydroxybenzene; PG) and its derivatives are phenolic compounds that are used for various industrial applications. Current methods to synthesize PG are not sustainable due to the requirement for carbon-based precursors and co-production of toxic byproducts. Here, we describe a more sustainable production of PG using plants expressing a native bacterial or a codon-optimized synthetic PhlD targeted to either the cytosol or chloroplasts. Transgenic lines were analyzed for the production of PG using gas and liquid chromatography coupled to mass spectroscopy. Phloroglucinol was produced in all transgenic lines and the line with the highest PhlD transcript level showed the most accumulation of PG. Over 80% of the produced PG was glycosylated to phlorin. Arabidopsis leaves have the machinery to glycosylate PG to form phlorin, which can be hydrolyzed enzymatically to produce PG. Furthermore, the metabolic profile of plants with PhlD in either the cytosol or chloroplasts was altered. Our results provide evidence that plants can be engineered to produce PG using a bacterial gene. Phytoproduction of PG using a bacterial gene paves the way for further genetic manipulations to enhance the level of PG with implications for the commercial production of this important platform chemical in plants.
Wei, Chao-Yang; Liao, Ning-Bo; Zhang, Yu; Ye, Xing-Qian; Li, Shan; Hu, Ya-Qin; Liu, Dong-Hong; Linhardt, Robert J; Wang, Xin; Chen, Shi-Guo
2017-09-01
A fucosylated chondroitin sulfate (FCS-pg) with highly repeated structure from Pearsonothuria graeffei was subjected to a in vitro fermentation model to investigate its fermentability and effects on human gut microflora. High performance liquid chromatography (HPLC) measurement found FCS-pg can be fermented to short chain fatty acids (SCFAs) by gut microflora from partial human fecal samples. 16S rRNA gene-based polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-DGGE) profiling and real-time quantitative PCR analysis showed that FCS-pg mainly increased the proportions of Clostridium cluster XI, Bacteriodes prevotella group, Bifidobacterium genus, Clostridium cluster I and Clostridium cluster XIVab, whereas the numbers of the Enterobacteriaceae and Lactobacillus decreased. These results indicated that FCS-pg was mainly fermented by Bacteroides, Bifidobacterium and Clostridium. It increased the content of probiotics bacteria in achieving health-enhancing effect, was slightly different than most sulfated polysaccharides from marine animals. The current study provides useful new information on the mechanism of absorption and functional activity on FCS-pg within the gastrointestinal tract of the human body. Copyright © 2017. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Al-Mayah, Adil; Moseley, Joanne; Hunter, Shannon; Brock, Kristy
2015-11-01
Biomechanical-based deformable image registration is conducted on the head and neck region. Patient specific 3D finite element models consisting of parotid glands (PG), submandibular glands (SG), tumor, vertebrae (VB), mandible, and external body are used to register pre-treatment MRI to post-treatment MR images to model the dose response using image data of five patients. The images are registered using combinations of vertebrae and mandible alignments, and surface projection of the external body as boundary conditions. In addition, the dose response is simulated by applying a new loading technique in the form of a dose-induced shrinkage using the dose-volume relationship. The dose-induced load is applied as dose-induced shrinkage of the tumor and four salivary glands. The Dice Similarity Coefficient (DSC) is calculated for the four salivary glands, and tumor to calculate the volume overlap of the structures after deformable registration. A substantial improvement in the registration is found by including the dose-induced shrinkage. The greatest registration improvement is found in the four glands where the average DSC increases from 0.53, 0.55, 0.32, and 0.37 to 0.68, 0.68, 0.51, and 0.49 in the left PG, right PG, left SG, and right SG, respectively by using bony alignment of vertebrae and mandible (M), body (B) surface projection and dose (D) (VB+M+B+D).
Application of screened Coulomb potential in fitting DBV star PG 0112+104
NASA Astrophysics Data System (ADS)
Chen, Y. H.
2018-03-01
With 78.7 d of observations for PG 0112+104, a pulsating DB star, from Campaign 8 of Kepler 2 mission, Hermes et al. made a detailed mode identification. A reliable mode identification, with 5 l = 1 modes, 3 l = 2 modes, and 3 l = 1 or 2 modes, was identified. Grids of DBV star models are evolved by WDEC with element diffusion effect of pure Coulomb potential and screened Coulomb potential. Fitting the identified modes of PG 0112+104 by the calculated ones, we studied the difference of element diffusion effect between adopting pure Coulomb potential and screened Coulomb potential. Our aim is to reduce the fitting error by studying new input physics. The starting models including their chemical composition profile are from white dwarf models evolved by MESA. They were calculated following the stellar evolution from the main sequence to the start of the white dwarf cooling sequences. The optimal parameters are basically consistent with that of previous spectroscopic and asteroseismological studies. The pure and screened Coulomb potential lead to different composition profiles of the C/O-He interface area. High k modes are very sensitive to the area. However, most of the observed modes for PG 0112+104 are low k modes. The σRMS taking the screened Coulomb potential is reduced by 4 per cent compared with taking the pure Coulomb potential when fitting the identified low k modes of PG 0112+104. Fitting the Kepler 2 data with our models improved the σRMS of the fit by 27 per cent.
Tam, J; Danilovich, N; Nilsson, K; Sairam, M R; Maysinger, D
2002-01-01
The follitropin receptor knockout (FORKO) mouse undergoes ovarian failure, thereby providing an animal model to investigate the consequences of the depletion of circulating estrogen in females. The estrogen deficiency causes marked defects in the female reproductive system, obesity, and skeletal abnormalities. In light of estrogen's known pleiotropic effects in the nervous system, our study examined the effects of genetically induced estrogen-testosterone imbalance on this system in female FORKO mice. Circulating concentrations of 17-beta-estradiol (E2) in FORKO mice are significantly decreased (FORKO -/-: 1.13+/-0.34 pg/ml; wild-type +/+: 17.6+/-3.5 pg/ml, P<0.0001, n=32-41); in contrast, testosterone levels are increased (-/-: 37.7+/-2.3 pg/ml; wild-type +/+: 3.9+/-1.7 pg/ml, P<0.005, n=25-33). The focus was on the activities of key enzymes in the central cholinergic and peripheral nervous systems, on dorsal root ganglia (DRGs) capacity for neurite outgrowth, and on the phosphorylation state of structural neurofilament (NF) proteins. Choline acetyltransferase activity was decreased in several central cholinergic structures (striatum 50+/-3%, hippocampus 24+/-2%, cortex 12+/-3%) and in DRGs (11+/-6%). Moreover, we observed aberrations in the enzymatic activities of mitogen-activated protein kinases (extracellular-regulated kinase and c-Jun N-terminal kinase) in the hippocampus, DRGs, and sciatic nerves. Hippocampal and sensory ganglia samples from FORKO mice contained hyper-phosphorylated NFs. Finally, explanted ganglia of FORKO mice displayed decreased neurite outgrowth (20-50%) under non-treated conditions and when treated with E2 (10 nM). Our results demonstrate that genetic depletion of circulating estrogen leads to biochemical and morphological changes in central and peripheral neurons, and underlie the importance of estrogen in the normal development and functioning of the nervous system. In particular, the findings suggest that an early and persisting absence of the steroid leads to neurodegenerative changes and identify several key enzymes that may contribute to the process. This model provides a system to explore the consequences of circulating estrogen deprivation and other hormonal imbalances in the nervous system.
NASA Astrophysics Data System (ADS)
Bayer, Anita D.; Lindeskog, Mats; Pugh, Thomas A. M.; Anthoni, Peter M.; Fuchs, Richard; Arneth, Almut
2017-02-01
Land-use and land-cover (LUC) changes are a key uncertainty when attributing changes in measured atmospheric CO2 concentration to its sinks and sources and must also be much better understood to determine the possibilities for land-based climate change mitigation, especially in the light of human demand on other land-based resources. On the spatial scale typically used in terrestrial ecosystem models (0.5 or 1°) changes in LUC over time periods of a few years or more can include bidirectional changes on the sub-grid level, such as the parallel expansion and abandonment of agricultural land (e.g. in shifting cultivation) or cropland-grassland conversion (and vice versa). These complex changes between classes within a grid cell have often been neglected in previous studies, and only net changes of land between natural vegetation cover, cropland and pastures accounted for, mainly because of a lack of reliable high-resolution historical information on gross land transitions, in combination with technical limitations within the models themselves. In the present study we applied a state-of-the-art dynamic global vegetation model with a detailed representation of croplands and carbon-nitrogen dynamics to quantify the uncertainty in terrestrial ecosystem carbon stocks and fluxes arising from the choice between net and gross representations of LUC. We used three frequently applied global, one recent global and one recent European LUC datasets, two of which resolve gross land transitions, either in Europe or in certain tropical regions. When considering only net changes, land-use-transition uncertainties (expressed as 1 standard deviation around decadal means of four models) in global carbon emissions from LUC (ELUC) are ±0.19, ±0.66 and ±0.47 Pg C a-1 in the 1980s, 1990s and 2000s, respectively, or between 14 and 39 % of mean ELUC. Carbon stocks at the end of the 20th century vary by ±11 Pg C for vegetation and ±37 Pg C for soil C due to the choice of LUC reconstruction, i.e. around 3 % of the respective C pools. Accounting for sub-grid (gross) land conversions significantly increased the effect of LUC on global and European carbon stocks and fluxes, most noticeably enhancing global cumulative ELUC by 33 Pg C (1750-2014) and entailing a significant reduction in carbon stored in vegetation, although the effect on soil C stocks was limited. Simulations demonstrated that assessments of historical carbon stocks and fluxes are highly uncertain due to the choice of LUC reconstruction and that the consideration of different contrasting LUC reconstructions is needed to account for this uncertainty. The analysis of gross, in addition to net, land-use changes showed that the full complexity of gross land-use changes is required in order to accurately predict the magnitude of LUC change emissions. This introduces technical challenges to process-based models and relies on extensive information regarding historical land-use transitions.
Memory and cognitive control in an integrated theory of language processing.
Slevc, L Robert; Novick, Jared M
2013-08-01
Pickering & Garrod's (P&G's) integrated model of production and comprehension includes no explicit role for nonlinguistic cognitive processes. Yet, how domain-general cognitive functions contribute to language processing has become clearer with well-specified theories and supporting data. We therefore believe that their account can benefit by incorporating functions like working memory and cognitive control into a unified model of language processing.
The OCO-2 tracks large increase in carbon release to the atmosphere during the 2014-2016 El Niño
NASA Astrophysics Data System (ADS)
Patra, Prabir
2017-04-01
The powerful El Niño event of 2015-2016 - the third most intense since the 1950s - has exerted a large impact on the Earth's natural climate system. The column-averaged CO2 dry-air mole fraction (XCO2) observations from the recently launched Orbiting Carbon Observatory-2 (OCO-2) satellite, from the Greenhouse gases observing satellite (GOSAT) and from the ground-based Total Carbon Column Observing Network (TCCON) are analyzed together with in situ observations for the period of September 2014 to October 2016 (25 months). From the differences between satellite (OCO-2) observations and simulations using an atmospheric chemistry-transport model, we estimate that, relative to the mean annual fluxes for 2013, over the period July 2015 to June 2016, the most recent El Niño has contributed to an excess CO2 emission from the Earth's surface (land+ocean) to the atmosphere in the range of 2.4 ± 0.2 PgC (1 Pg = 1015 g). The excess CO2 flux resulted primarily from reduction in vegetation uptake due to drought, and to a lesser degree from increased biomass burning. It is about the half of the CO2 flux anomaly (range: 4.4-6.7 PgC) estimated for the 1997/1998 El Niño. The annual total sink is estimated to be 3.9 ± 0.2 PgC for the assumed fossil fuel emission of 10.1 PgC in contrast to an average sink of more than 6 PgC yr-1 during 'reference' period of 2013-2014. The major uncertainty in attribution arise from error in anthropogenic emission trends, satellite data and atmospheric transport. We believe improvements in modeling atmospheric-CO2 are needed to enable attribution at smaller, regional scales.
Nie, Zhiqiang; Die, Qingqi; Yang, Yufei; Tang, Zhenwu; Wang, Qi; Huang, Qifei
2014-01-01
Polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) were overall measured and compared in ambient air, water, soils, and sediments along the upper reaches of the Haihe River of North China, so as to evaluate their concentrations, profiles, and to understand the processes of gas-particle partitioning and air-water/soil exchange. The following results were obtained: (1) The average concentrations (toxic equivalents, TEQs) of 2,3,7,8-PCDD/PCDF in air, water, sediment, and soil samples were 4,855 fg/m(3), 9.5 pg/L, 99.2 pg/g dry weight (dw), and 56.4 pg/g (203 fg TEQ/m(3), 0.46 pg TEQ/L, 2.2 pg TEQ/g dw, and 1.3 pg TEQ/g, respectively), respectively. (2) Although OCDF, 1,2,3,4,6,7,8-HpCDF, OCDD, and 1,2,3,4,6,7,8-HpCDD were the dominant congeners among four environmental sinks, obvious discrepancies of these congener and homologue patterns of PCDD/PCDF were observed still. (3) Significant linear correlations for PCDD/PCDF were observed between the gas-particle partition coefficient (K p) and the subcooled liquid vapor pressure (P L (0)) and octanol-air partition coefficient (K oa). (4) Fugacity fraction values of air-water exchange indicated that most of PCDD/PCDF homologues were dominated by net volatilization from water into air. The low-chlorinated PCDD/PCDF (tetra- to hexa-) presented a strong net volatilization from the soil into air, while high-chlorinated PCDD/PCDF (hepta- to octa-) were mainly close to equilibrium for air-soil exchange.
Terrestrial nitrogen–carbon cycle interactions at the global scale
Zaehle, S.
2013-01-01
Interactions between the terrestrial nitrogen (N) and carbon (C) cycles shape the response of ecosystems to global change. However, the global distribution of nitrogen availability and its importance in global biogeochemistry and biogeochemical interactions with the climate system remain uncertain. Based on projections of a terrestrial biosphere model scaling ecological understanding of nitrogen–carbon cycle interactions to global scales, anthropogenic nitrogen additions since 1860 are estimated to have enriched the terrestrial biosphere by 1.3 Pg N, supporting the sequestration of 11.2 Pg C. Over the same time period, CO2 fertilization has increased terrestrial carbon storage by 134.0 Pg C, increasing the terrestrial nitrogen stock by 1.2 Pg N. In 2001–2010, terrestrial ecosystems sequestered an estimated total of 27 Tg N yr−1 (1.9 Pg C yr−1), of which 10 Tg N yr−1 (0.2 Pg C yr−1) are due to anthropogenic nitrogen deposition. Nitrogen availability already limits terrestrial carbon sequestration in the boreal and temperate zone, and will constrain future carbon sequestration in response to CO2 fertilization (regionally by up to 70% compared with an estimate without considering nitrogen–carbon interactions). This reduced terrestrial carbon uptake will probably dominate the role of the terrestrial nitrogen cycle in the climate system, as it accelerates the accumulation of anthropogenic CO2 in the atmosphere. However, increases of N2O emissions owing to anthropogenic nitrogen and climate change (at a rate of approx. 0.5 Tg N yr−1 per 1°C degree climate warming) will add an important long-term climate forcing. PMID:23713123
Terrestrial nitrogen-carbon cycle interactions at the global scale.
Zaehle, S
2013-07-05
Interactions between the terrestrial nitrogen (N) and carbon (C) cycles shape the response of ecosystems to global change. However, the global distribution of nitrogen availability and its importance in global biogeochemistry and biogeochemical interactions with the climate system remain uncertain. Based on projections of a terrestrial biosphere model scaling ecological understanding of nitrogen-carbon cycle interactions to global scales, anthropogenic nitrogen additions since 1860 are estimated to have enriched the terrestrial biosphere by 1.3 Pg N, supporting the sequestration of 11.2 Pg C. Over the same time period, CO2 fertilization has increased terrestrial carbon storage by 134.0 Pg C, increasing the terrestrial nitrogen stock by 1.2 Pg N. In 2001-2010, terrestrial ecosystems sequestered an estimated total of 27 Tg N yr(-1) (1.9 Pg C yr(-1)), of which 10 Tg N yr(-1) (0.2 Pg C yr(-1)) are due to anthropogenic nitrogen deposition. Nitrogen availability already limits terrestrial carbon sequestration in the boreal and temperate zone, and will constrain future carbon sequestration in response to CO2 fertilization (regionally by up to 70% compared with an estimate without considering nitrogen-carbon interactions). This reduced terrestrial carbon uptake will probably dominate the role of the terrestrial nitrogen cycle in the climate system, as it accelerates the accumulation of anthropogenic CO2 in the atmosphere. However, increases of N2O emissions owing to anthropogenic nitrogen and climate change (at a rate of approx. 0.5 Tg N yr(-1) per 1°C degree climate warming) will add an important long-term climate forcing.
Understanding the Dynamics of Soil Carbon in CMIP5 Models
NASA Astrophysics Data System (ADS)
Todd-Brown, K. E.; Luo, Y.; Randerson, J. T.; Allison, S. D.; Smith, M. J.
2014-12-01
Soil carbon stocks have the potential to be a strong source or sink for carbon dioxide over the next century, playing a critical role in climate change. These stocks are the result of small differences between much larger primary carbon fluxes: gross primary production, litter fall, autotrophic respiration and heterotrophic respiration. There was little agreement on predicted soil carbon stocks between Earth system models (ESMs) in the most recent Climate Model Intercomparison Project. Predicted present-day stocks ranged from roughly 500 Pg to over 3000 Pg and predicted changes over the 21st century ranged from -70 Pg to +250 Pg). The primary goal of this study was to understand why such large differences exist. We constructed four reduced complexity models to describe the primary carbon fluxes, making different assumptions about how soil carbon fluxes are modelled in ESMs. For each of these reduced complexity models we statistically inferred the most likely model parameters given the gridded ESM simulation outputs. Gross primary production was best explained by incoming short wave radiation, CO2 concentration, and leaf area index (global GPP comparison of simulation vs reduced complexity model of R2>0.9 (p < 1e-4) with slopes between 0.65 and 1.2 and intercepts between -13 and 67 Pg C yr-1). Autotrophic respiration was best explained as a proportion of GPP (R2 > 0.9 (p < 1e-4) with slopes between 0.78 and 1.1 and intercepts between -15 and 14 Pg C yr-1). Flux between the vegetation and soil pools were best explained as a proportion of the vegetation carbon stock (R2 > 0.9 (p < 1e-4) with slopes between 0.9 and 2.1 and intercepts between -65 and 25 Pg C yr-1). Finally heterotrophic respiration was best explained as a function of soil carbon stocks and soil temperature (R2 > 0.9 (p < 1e-4) with slopes between 0.7 and 1.5 and intercepts between -40 and 15 Pg C yr-1). This research suggests three main lines of decomposition model improvement: 1) improve connecting sub-models, 2) data integration to improve parameterization, 3) modification of model structure. The implied variation in RCM parameterization suggests that data integration could constrain model simulation results. However, the similarity in model structure may lead to systematic biases in the simulations without the introduction of new model structures.
Proglucagons in vertebrates: Expression and processing of multiple genes in a bony fish.
Busby, Ellen R; Mommsen, Thomas P
2016-09-01
In contrast to mammals, where a single proglucagon (PG) gene encodes three peptides: glucagon, glucagon-like peptide 1 and glucagon-like peptide 2 (GLP-1; GLP-2), many non-mammalian vertebrates carry multiple PG genes. Here, we investigate proglucagon mRNA sequences, their tissue expression and processing in a diploid bony fish. Copper rockfish (Sebastes caurinus) express two independent genes coding for distinct proglucagon sequences (PG I, PG II), with PG II lacking the GLP-2 sequence. These genes are differentially transcribed in the endocrine pancreas, the brain, and the gastrointestinal tract. Alternative splicing identified in rockfish is only one part of this complex regulation of the PG transcripts: the system has the potential to produce two glucagons, four GLP-1s and a single GLP-2, or any combination of these peptides. Mass spectrometric analysis of partially purified PG-derived peptides in endocrine pancreas confirms translation of both PG transcripts and differential processing of the resulting peptides. The complex differential regulation of the two PG genes and their continued presence in this extant teleostean fish strongly suggests unique and, as yet largely unidentified, roles for the peptide products encoded in each gene. Copyright © 2016 Elsevier Inc. All rights reserved.
Ding, Zhong-Yuan; Mao, Xiao-Xuan; Ma, Zi-Long; Tian, Hui; Guo, Qiang; Huang, Tao; Gao, Hong; Li, Jun; Zhang, Gan
2013-04-01
Air samples were seasonally collected in Hexi Corridor and Lanzhou, Gansu province, using polyurethane foam (PUF) based passive air samplers for a year and determined hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs). Atmospheric concentrations of sigma HCHs (alpha-HCH +beta-HCH +gamma-HCH +delta-HCH) and sigma DDTs (p,p'-DDT + o,p'-DDT + p,p'-DDE + p,p'-DDD) were 86.22 pg x m(-3) and 34.06 pg x m(-3) in Hexi Corridor and Lanzhou with background concentrations of 54.41 pg x m(-3) and 21.56 pg x m(-3), respectively, which were lower than previously reported values elsewhere. In general, the seasonal pollution characteristics of sigma HCHs and sigma DDTs exhibited higher levels with the average concentrations of 127.4 pg x m(-3) and 47.06 pg x m(-3) in autumn, respectively. Furthermore, relatively higher residual concentrations of HCHs and DDTs were found in Jiuquan, Anxi and Zhangye, relating to their more arable lands and more intensively historical usage. Source apportionment indicated HCHs were mainly originated from historical technical-HCHs residues and recent Lindane usage. Recently introduced technical-DDTs was highly responsible for DDTs contamination, whereas the higher concentrations of o,p'-DDT observed in Jiuquan and Anxi may be attributed to dicofol usage. In addition, human exposure to HCHs and DDTs in Hexi Corridor and Lanzhou via inhalation could be relatively low.
Yu, Youjian; Liang, Ying; Lv, Meiling; Wu, Jian; Lu, Gang; Cao, Jiashu
2014-01-01
Polygalacturonase (PG, EC3.2.1.15), one of the hydrolytic enzymes associated with the modification of pectin network in plant cell wall, has an important role in various cell-separation processes that are essential for plant development. PGs are encoded by a large gene family in plants. However, information on this gene family in plant development remains limited. In the present study, 53 and 62 putative members of the PG gene family in cucumber and watermelon genomes, respectively, were identified by genome-wide search to explore the composition, structure, and evolution of the PG family in Cucurbitaceae crops. The results showed that tandem duplication could be an important factor that contributes to the expansion of the PG genes in the two crops. The phylogenetic and evolutionary analyses suggested that PGs could be classified into seven clades, and that the exon/intron structures and intron phases were conserved within but divergent between clades. At least 24 ancestral PGs were detected in the common ancestor of Arabidopsis and Cucumis sativus. Expression profile analysis by quantitative real-time polymerase chain reaction demonstrated that most CsPGs exhibit specific or high expression pattern in one of the organs/tissues. The 16 CsPGs associated with fruit development could be divided into three subsets based on their specific expression patterns and the cis-elements of fruit-specific, endosperm/seed-specific, and ethylene-responsive exhibited in their promoter regions. Our comparative analysis provided some basic information on the PG gene family, which would be valuable for further functional analysis of the PG genes during plant development. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Draeger, E; Chen, H; Polf, J
2016-06-15
Purpose: To report on the initial developments of a clinical 3-dimensional (3D) prompt gamma (PG) imaging system for proton radiotherapy range verification. Methods: The new imaging system under development consists of a prototype Compton camera to measure PG emission during proton beam irradiation and software to reconstruct, display, and analyze 3D images of the PG emission. For initial test of the system, PGs were measured with a prototype CC during a 200 cGy dose delivery with clinical proton pencil beams (ranging from 100 MeV – 200 MeV) to a water phantom. Measurements were also carried out with the CC placedmore » 15 cm from the phantom for a full range 150 MeV pencil beam and with its range shifted by 2 mm. Reconstructed images of the PG emission were displayed by the clinical PG imaging software and compared to the dose distributions of the proton beams calculated by a commercial treatment planning system. Results: Measurements made with the new PG imaging system showed that a 3D image could be reconstructed from PGs measured during the delivery of 200 cGy of dose, and that shifts in the Bragg peak range of as little as 2 mm could be detected. Conclusion: Initial tests of a new PG imaging system show its potential to provide 3D imaging and range verification for proton radiotherapy. Based on these results, we have begun work to improve the system with the goal that images can be produced from delivery of as little as 20 cGy so that the system could be used for in-vivo proton beam range verification on a daily basis.« less
NASA Astrophysics Data System (ADS)
Gallimore, P. J.; Griffiths, P. T.; Pope, F. D.; Reid, J. P.; Kalberer, M.
2017-04-01
The chemical composition of organic aerosols profoundly influences their atmospheric properties, but a detailed understanding of heterogeneous and in-particle reactivity is lacking. We present here a combined experimental and modeling study of the ozonolysis of oleic acid particles. An online mass spectrometry (MS) method, Extractive Electrospray Ionization (EESI), is used to follow the composition of the aerosol at a molecular level in real time; relative changes in the concentrations of both reactants and products are determined during aerosol aging. The results show evidence for multiple non-first-order reactions involving stabilized Criegee intermediates, including the formation of secondary ozonides and other oligomers. Offline liquid chromatography MS is used to confirm the online MS assignment of the monomeric and dimeric products. We explain the observed EESI-MS chemical composition changes, and chemical and physical data from previous studies, using a process-based aerosol chemistry simulation, the Pretty Good Aerosol Model (PG-AM). In particular, we extend previous studies of reactant loss by demonstrating success in reproducing the time dependence of product formation and the evolving particle size. This advance requires a comprehensive chemical scheme coupled to the partitioning of semivolatile products; relevant reaction and evaporation parameters have been refined using our new measurements in combination with PG-AM.
Seasonal and spatial distributions of atmospheric polychlorinated naphthalenes in Shanghai, China.
Die, Qingqi; Nie, Zhiqiang; Fang, Yanyan; Yang, Yufei; Gao, Xingbao; Tian, Yajun; He, Jie; Liu, Feng; Huang, Qifei; Tian, Shulei
2016-02-01
Air samples were collected in Shanghai during summer and winter 2013, and the gas and particulate concentrations of polychlorinated naphthalenes (PCNs) were measured. All 75 congeners were quantified and the corresponding toxic equivalents (TEQs) were calculated. PCN concentrations were higher in summer than winter, at 8.22-102 pg/m(3) (average of 61.3 pg/m(3)) in summer and 16.5-61.1 pg/m(3) (average of 37.7 pg/m(3)) in winter. Their seasonal TEQ values were in contrast, at 1.35-7.31 fg/m(3) (average of 3.84 fg/m(3)) in summer and 4.08-23.3 fg/m(3) (average of 8.80 fg/m(3)) in winter, because of the seasonal change in congener profiles. Tri-CNs were the predominant homologs in both the summer and winter samples. However, the major congeners in summer were PCNs containing less chlorine, but these decreased over winter. Air mass back trajectories suggested that wind direction over various sites was similar in the summer and winter seasons, yet there were clear seasonal variations in atmospheric PCN concentrations. Ratios of several characteristic congeners were calculated and the results indicated that the ratios varied only to a limited extent with PCN emissions profile from industrial thermal sources, but varied strongly with profiles of technical PCN and PCN contaminants in polychlorinated biphenyl mixtures. The results of principal component analysis suggest that local industrial thermal emissions (thermal processes containing waste incineration and secondary metal smelting processes) still play a considerable role in influencing the atmospheric PCNs in Shanghai. Copyright © 2015 Elsevier Ltd. All rights reserved.
Systemic LPS and inflammatory response during consecutive days of exercise in heat.
Barberio, M D; Elmer, D J; Laird, R H; Lee, K A; Gladden, B; Pascoe, D D
2015-03-01
This investigation studied circulating LPS activity, potential intestinal damage, and the systemic inflammatory response (SIR) during the exercise heat acclimation process. 8 healthy males (Age=24±3 years) ran in a hot environment on 5 consecutive days until core temperature (Tc) was elevated 2°C above rest. Plasma was obtained pre-, post-, 1 h post-, and 3 h post-exercise on the 1(st), 3(rd), and 5(th) day of exercise and analyzed for TNF-α, IL-6, IL-10, IL-1ra, LPS, and intestinal fatty acid-binding protein (I-FABP). Plasma LPS (1.1 EU·ml(-1)±0.1 vs. 0.7 EU·ml(-1)±0.03; P<0.01) and I-FABP (930.7 pg·ml(-1)±149.0 vs. 640.2 pg·ml(-1)±125.0; P<0.001) were significantly increased post-exercise each. The SIR remained largely unchanged during the study except for TNF-α. Plasma TNF-α was significantly lower on Day 5 at 1 h (3.2 pg·ml(-1)±0.6 vs. 4.5 pg·ml(-1)±0.8; P=0.01) and 3 h (3.6 pg·ml(-1)±0.8 vs. 4.8 pg·ml(-1)±0.9; P=0.05) post-exercise as compared to Day 1. Findings indicate that adaptations to exercise in the heat resulting in reductions of intestinal damage and plasma LPS activity require longer time periods in moderately trained males. © Georg Thieme Verlag KG Stuttgart · New York.
Method for measuring the unbinding energy of strongly-bound membrane-associated proteins.
Bauve, Elisa La; Vernon, Briana C; Ye, Dongmei; Rogers, David M; Siegrist, Cathryn M; Carson, Bryan D; Rempe, Susan B; Zheng, Aihua; Kielian, Margaret; Shreve, Andrew P; Kent, Michael S
2016-11-01
We describe a new method to measure the activation energy for unbinding (enthalpy ΔH* u and free energy ΔG* u ) of a strongly-bound membrane-associated protein from a lipid membrane. It is based on measuring the rate of release of a liposome-bound protein during centrifugation on a sucrose gradient as a function of time and temperature. The method is used to determine ΔH* u and ΔG* u for the soluble dengue virus envelope protein (sE) strongly bound to 80:20 POPC:POPG liposomes at pH5.5. ΔH* u is determined from the Arrhenius equation whereas ΔG* u is determined by fitting the data to a model based on mean first passage time for escape from a potential well. The binding free energy ΔG b of sE was also measured at the same pH for the initial, predominantly reversible, phase of binding to a 70:30 PC:PG lipid bilayer. The unbinding free energy (20±3kcal/mol, 20% PG) was found to be roughly three times the binding energy per monomer, (7.8±0.3kcal/mol for 30% PG, or est. 7.0kcal/mol for 20% PG). This is consistent with data showing that free sE is a monomer at pH5.5, but assembles into trimers after associating with membranes. This new method to determine unbinding energies should be useful to understand better the complex interactions of integral monotopic proteins and strongly-bound peripheral membrane proteins with lipid membranes. Copyright © 2016 Elsevier B.V. All rights reserved.
Accelerating Net Terrestrial Carbon Uptake During the Warming Hiatus Due to Reduced Respiration
NASA Technical Reports Server (NTRS)
Ballantyne, Ashley; Smith, William; Anderegg, William; Kauppi, Pekka; Sarmiento, Jorge; Tans, Pieter; Shevliakova, Elena; Pan, Yude; Poulter, Benjamin; Anav, Alessandro;
2017-01-01
The recent warming hiatus presents an excellent opportunity to investigate climate sensitivity of carbon cycle processes. Here we combine satellite and atmospheric observations to show that the rate of net biome productivity (NBP) has significantly accelerated from - 0.007 +/- 0.065 PgC yr(exp -2) over the warming period (1982 to 1998) to 0.119 +/- 0.071 PgC yr(exp -2) over the warming hiatus (19982012). This acceleration in NBP is not due to increased primary productivity, but rather reduced respiration that is correlated (r = 0.58; P = 0.0007) and sensitive ( y = 4.05 to 9.40 PgC yr(exp -1) per C) to land temperatures. Global land models do not fully capture this apparent reduced respiration over the warming hiatus; however, an empirical model including soil temperature and moisture observations better captures the reduced respiration.
Accelerating net terrestrial carbon uptake during the warming hiatus due to reduced respiration
NASA Astrophysics Data System (ADS)
Ballantyne, Ashley; Smith, William; Anderegg, William; Kauppi, Pekka; Sarmiento, Jorge; Tans, Pieter; Shevliakova, Elena; Pan, Yude; Poulter, Benjamin; Anav, Alessandro; Friedlingstein, Pierre; Houghton, Richard; Running, Steven
2017-01-01
The recent `warming hiatus' presents an excellent opportunity to investigate climate sensitivity of carbon cycle processes. Here we combine satellite and atmospheric observations to show that the rate of net biome productivity (NBP) has significantly accelerated from -0.007 +/- 0.065 PgC yr-2 over the warming period (1982 to 1998) to 0.119 +/- 0.071 PgC yr-2 over the warming hiatus (1998-2012). This acceleration in NBP is not due to increased primary productivity, but rather reduced respiration that is correlated (r = 0.58 P = 0.0007) and sensitive (γ = 4.05 to 9.40 PgC yr-1 per °C) to land temperatures. Global land models do not fully capture this apparent reduced respiration over the warming hiatus; however, an empirical model including soil temperature and moisture observations better captures the reduced respiration.
Wu, Shusong; Yano, Satoshi; Chen, Jihua; Hisanaga, Ayami; Sakao, Kozue; He, Xi; He, Jianhua; Hou, De-Xing
2017-06-28
Lonicera caerulea L. berry polyphenols (LCBP) are considered as major components for bioactivity. This study aimed to clarify the molecular mechanisms by monitoring inflammatory and antioxidant mediator actions in lipopolysaccharide (LPS)-induced mouse paw edema and macrophage cell model. LCBP significantly attenuated LPS-induced paw edema (3.0 ± 0.1 to 2.8 ± 0.1 mm, P < 0.05) and reduced (P < 0.05) serum levels of monocyte chemotactic protein-1 (MCP-1, 100.9 ± 2.3 to 58.3 ± 14.5 ng/mL), interleukin (IL)-10 (1596.1 ± 424.3 to 709.7 ± 65.7 pg/mL), macrophage inflammatory protein (MIP)-1α (1761.9 ± 208.3 to 1369.1 ± 56.4 pg/mL), IL-6 (1262.8 ± 71.7 to 499.0 ± 67.1 pg/mL), IL-4 (93.3 ± 25.7 to 50.7 ± 12.5 pg/mL), IL-12(p-70) (580.4 ± 132.0 to 315.2 ± 35.1 pg/mL), and tumor necrosis factor-α (TNF-α, 2045.5 ± 264.9 to 1270.7 ± 158.6 pg/mL). Cell signaling analysis revealed that LCBP inhibited transforming growth factor β activated kinase-1 (TAK1)-mediated mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways, and enhanced the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and manganese-dependent superoxide dismutase (MnSOD) in earlier response. Moreover, cyanidin 3-glucoside (C3G) and (-)-epicatechin (EC), two major components of LCBP, directly bound to TAK1. These data demonstrated that LCBP might inhibit LPS-induced inflammation by modulating both inflammatory and antioxidant mediators.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hodgson, A.T.; Daisey, J.M.; Alevantis, L.E.
Three volatile nitrogen-containing compounds, 3-ethenylpyridine (3-EP), pyridine and pyrrole, were investigated as potential tracers for determining the contribution of environmental tobacco smoke (ETS) to concentrations of volatile organic compounds (VOCs) in indoor environments with smoking. The source emission rates of the three tracers and ten selected VOCs in ETS were first measured in a room-size environmental chamber for a market-weighted selection of six commercial cigarettes. The ratios of the emission rates of the tracers to the emission rates of the selected VOCs were calculated and compared among the six brands. The utility of the tracers was then evaluated in amore » field study conducted in five office buildings. Samples for VOCs were collected in designated smoking areas and adjoining non-smoking areas, air change rates were measured, and smoking rates were documented. Concentrations of the three tracers in the smoking areas were calculated using a mass-balance model and compared to their measured concentrations. Based on this comparison, 3-EP was selected as the most suitable tracer for the volatile components of ETS, although pyrrole is also potentially useful. Using 3-EP as the tracer, the contributions of ETS to the measured concentrations of the selected VOCs in the smoking areas were estimated by apportionment. ETS was estimated to contribute 57 to 84 percent (4.1 to 26 pg m{sup -3}) of the formaldehyde concentrations, 44 to 69 percent (0.9 to 5.8 pg m{sup -3}) of the 2-butanone concentrations, 37 to 58 percent (1.3 to 8.2 pg m{sup -3}) of the benzene concentrations, and 20 to 69 percent (0.5 to 3.0 pg m{sup -3}) of the styrene concentrations. The fractional contributions of ETS to the concentrations of acetone, toluene, ethylbenzene, xylene isomers and d-limonene were all less than 50 percent.« less
North Greenland's Ice Shelves and Ocean Warming
NASA Astrophysics Data System (ADS)
Muenchow, A.; Schauer, U.; Padman, L.; Melling, H.; Fricker, H. A.
2014-12-01
Rapid disintegration of ice shelves (the floating extensions of marine-terminating glaciers) can lead to increasing ice discharge, thinning upstream ice sheets, rising sea level. Pine Island Glacier, Antarctica, and Jacobshavn Isbrae, Greenland, provide prominent examples of these processes which evolve at decadal time scales. We here focus on three glacier systems north of 78 N in Greenland, each of which discharges more than 10 Gt per year of ice and had an extensive ice shelf a decade ago; Petermann Gletscher (PG), Niogshalvfjerdsfjorden (79N), and Zachariae Isstrom (ZI). We summarize and discuss direct observations of ocean and glacier properties for these systems as they have evolved in the northwest (PG) and northeast (79N and ZI) of Greenland over the last two decades. We use a combination of modern and historical snapshots of ocean temperature and salinity (PG, 79N, ZI), moored observations in Nares Strait (PG), and snapshots of temperature and velocity fields on the broad continental shelf off northeast Greenland (79N, ZI) collected between 1993 and 2014. Ocean warming adjacent to PG has been small relative to the ocean warming adjacent to 79N and ZI; however, ZI lost its entire ice shelf during the last decade while 79N, less than 70 km to the north of ZI, remained stable. In contrast, PG has thinned by about 10 m/y just prior to shedding two ice islands representing almost half its ice shelf area or a fifth by volume. At PG advective ice flux divergence explains about half of the dominantly basal melting while response to non-steady external forcing explains the other half. The observations at PG,79N, and ZI suggest that remotely sensed ambient surface ocean temperatures are poor proxies to explain ice shelf thinning and retreat. We posit that local dynamics of the subsurface ocean heat flux matters most. Ocean heat must first be delivered over the sill into the fjord and then within the ice shelf cavity to the base of the shelf near the grounding line. Models of glacier-ocean interaction must represent both bottom topography and closely related ocean dynamics and mixing at their dynamically relevant scales within a density stratified water column. Projects for such integrated ocean-glacier observations are in the planning stages for 79N and PG.
Light Competition and Carbon Partitioning-Allocation in an improved Forest Ecosystem Model
NASA Astrophysics Data System (ADS)
Collalti, Alessio; Santini, Monia; Valentini Valentini, Riccardo
2010-05-01
In Italy about 100.000 km2 are covered by forests. This surface is the 30% of the whole national land and this shows how the forests are important both for socio-economic and for environmental aspects. Forests changes affect a delicate balance that involve not only vegetation components but also bio-geochemical cycles and global climate. The knowledge of the amount of Carbon sequestered by forests represents a precious information for their sustainable management in the framework of climate changes. Primary studies in terms of model about this important issue, has been done through Forest Ecosystem Model (FEM), well known and validated as 3PG (Landsberg et Waring, 1997; Sands 2004). It is based on light use efficiency approach at the canopy level. The present study started from the original model 3PG, producing an improved version that uses many of explicit formulations of all relevant ecophysiological processes but makes it able to be applied for natural forests. The mutual interaction of forest growth and light conditions causes vertical and horizontal differentiation in the natural forest mosaic. Only ecophysiological parameters which can be either directly measured or estimates with reasonable certainty are used. The model has been written in C language and has been created considering a tri-dimensional cell structure with different vertical layers depending on the forest type that has to be simulated. This 3PG 'improved' version enable to work on multi-layer and multi-species forests type with cell resolution of one hectare for the typical Italian forest species. The multi-layer version is the result of the implementation and development of Lambert-Beer law for the estimation of intercepted, absorbed and transmitted light through different storeys of the forest. It is possible estimates, for each storey, a Par value (Photosynthetic Active Radiation) through Leaf Area Index (LAI), Light Extinction Coefficient and cell Canopy Cover using a "Big Leaf" approach. Hence, the presence of a cohort in a storey determines the amount of light received for the photosynthetic processes. The population density (numbers of trees per cell) represents a good competition index for determining the tree crown structure and tree crown dimension within a forest population. The tree crown tend to branch out horizontally to intercept as much light as possible. The model assess the structure of the tree crown both vertically and horizontally on the base of the population density and it up-scales the result to the whole stand. The canopy depth and the percentage of horizontal coverage determines moreover a crowding competition index that lead to a specific biomass partitioning-allocation ratio among the different tree components (foliage, roots and stem) and especially for the stem affecting Height-Diameter (at breast height) ratio. In this model, Height-Diameter ratio is used as an alternative competition index in determining the vigour and the strength of competition on free growth status of trees. The forest dominant vegetative cover affects moreover the presence of a dominated layer, it influences its yield and its Carbon stocking capacity and hence it influences the forest ecosystem CO2 carbon balance. From this model it is possible to simulate the impact of Climate Change on forests, the feedback of one or more dominated layers in terms of CO2 uptake in a forest stand and the effects of forest management activities for the next years.
Olanca, Burcu; Cakirogullari, Gul Celik; Ucar, Yunus; Kirisik, Dursun; Kilic, Devrim
2014-01-01
The aim of the study is to determine concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and indicator PCBs (ind-PCBs) in eggs from cage hens without soil contact, pasteurized egg samples and imported egg yolk powder samples in Turkey. Concentrations of PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs in eggs and pasteurized egg samples are in the range of 0.247-1.527 pg WHO-TEQ(2005)g(-1) fat, 0.282-1.762 pg WHO-TEQ(2005)g(-1) fat and 202-1,235 pg g(-1) fat, respectively. For egg yolk powder samples, concentrations of PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs are in the range of 0.122-0.494 pg WHO-TEQ(2005)g(-1) fat, 0.214-0.640 pg WHO-TEQ(2005)g(-1) fat and 217-1,498 pg g(-1) fat, respectively. All results for PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs are below the values of 2.5 pg WHO-TEQ(2005)g(-1) fat, 5.0 pg WHO-TEQ(2005)g(-1) fat and 40 ng g(-1) fat imposed in Turkish Regulation for eggs and egg products, respectively. In all samples 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD and PCB126 are the most prominent congeners. Mean estimated daily exposure to PCDD/Fs and dl-PCBs for Turkish population from egg is 0.011 pg WHO-TEQ(2005)d(-1)kg body weight (bw)(-1). Although the exposure levels are below the TDI of 2 pg WHO-TEQ(1998)kg bw(-1), the results were based only on consumption of egg. In order to estimate total dietary intake for Turkish population, various food items should be investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.
Kowalska, Joanna; Wypijewska del Nogal, Anna; Darzynkiewicz, Zbigniew M.; Buck, Janina; Nicola, Corina; Kuhn, Andreas N.; Lukaszewicz, Maciej; Zuberek, Joanna; Strenkowska, Malwina; Ziemniak, Marcin; Maciejczyk, Maciej; Bojarska, Elzbieta; Rhoads, Robert E.; Darzynkiewicz, Edward; Sahin, Ugur; Jemielity, Jacek
2014-01-01
Modified mRNA cap analogs aid in the study of mRNA-related processes and may enable creation of novel therapeutic interventions. We report the synthesis and properties of 11 dinucleotide cap analogs bearing a single boranophosphate modification at either the α-, β- or γ-position of the 5′,5′-triphosphate chain. The compounds can potentially serve either as inhibitors of translation in cancer cells or reagents for increasing expression of therapeutic proteins in vivo from exogenous mRNAs. The BH3-analogs were tested as substrates and binding partners for two major cytoplasmic cap-binding proteins, DcpS, a decapping pyrophosphatase, and eIF4E, a translation initiation factor. The susceptibility to DcpS was different between BH3-analogs and the corresponding analogs containing S instead of BH3 (S-analogs). Depending on its placement, the boranophosphate group weakened the interaction with DcpS but stabilized the interaction with eIF4E. The first of the properties makes the BH3-analogs more stable and the second, more potent as inhibitors of protein biosynthesis. Protein expression in dendritic cells was 2.2- and 1.7-fold higher for mRNAs capped with m27,2′-OGppBH3pG D1 and m27,2′-OGppBH3pG D2, respectively, than for in vitro transcribed mRNA capped with m27,3′-OGpppG. Higher expression of cancer antigens would make mRNAs containing m27,2′-OGppBH3pG D1 and m27,2′-OGppBH3pG D2 favorable for anticancer immunization. PMID:25150148
NASA Astrophysics Data System (ADS)
Yue, C.; Ciais, P.; Cadule, P.; Thonicke, K.; van Leeuwen, T. T.
2015-05-01
Carbon dioxide emissions from wild and anthropogenic fires return the carbon absorbed by plants to the atmosphere, and decrease the sequestration of carbon by land ecosystems. Future climate warming will likely increase the frequency of fire-triggering drought, so that the future terrestrial carbon uptake will depend on how fires respond to altered climate variation. In this study, we modelled the role of fires in the global terrestrial carbon balance for 1901-2012, using the ORCHIDEE global vegetation model equipped with the SPITFIRE model. We conducted two simulations with and without the fire module being activated, using a static land cover. The simulated global fire carbon emissions for 1997-2009 are 2.1 Pg C yr-1, which is close to the 2.0 Pg C yr-1 as estimated by GFED3.1. The simulated land carbon uptake after accounting for emissions for 2003-2012 is 3.1 Pg C yr-1, which is within the uncertainty of the residual carbon sink estimation (2.8 ± 0.8 Pg C yr-1). Fires are found to reduce the terrestrial carbon uptake by 0.32 Pg C yr-1 over 1901-2012, or 20% of the total carbon sink in a world without fire. The fire-induced land sink reduction (SRfire) is significantly correlated with climate variability, with larger sink reduction occurring in warm and dry years, in particular during El Niño events. Our results suggest a "fire respiration partial compensation". During the 10 lowest SRfire years (SRfire = 0.17 Pg C yr-1), fires mainly compensate for the heterotrophic respiration that would occur in a world without fire. By contrast, during the 10 highest SRfire fire years (SRfire = 0.49 Pg C yr-1), fire emissions far exceed their respiration partial compensation and create a larger reduction in terrestrial carbon uptake. Our findings have important implications for the future role of fires in the terrestrial carbon balance, because the capacity of terrestrial ecosystems to sequester carbon will be diminished by future climate change characterized by increased frequency of droughts and extreme El Niño events.
Wilson, Michael J; Vassileva, Jasmin
2018-01-01
This study explored how different forms of reward-based decision-making are associated with pathological gambling (PG) among abstinent individuals with prior dependence on different classes of drugs. Participants had lifetime histories of either "pure" heroin dependence ( n = 64), "pure" amphetamine dependence ( n = 51), or polysubstance dependence ( n = 89), or had no history of substance dependence ( n = 133). Decision-making was assessed via two neurocognitive tasks: (1) the Iowa Gambling Task (IGT), a measure of decision-making under ambiguity (i.e., uncertain risk contingencies); and (2) the Cambridge Gambling task (CGT), a measure of decision-making under risk (i.e., explicit risk contingencies). The main effects of neurocognitive performance and drug class on PG (defined as ≥3 DSM-IV PG symptoms) as well as their interactional effects were assessed via multiple linear regression. Two CGT indices of decision-making under risk demonstrated positive main effects on PG. Interaction effects indicated that the effects of decision-making under risk on PG were largely consistent across participant groups. Notably, a linear relationship between greater CGT Risk-Taking and PG symptoms was not observed among amphetamine users, whereas IGT performance was selectively and positively associated with PG in polysubstance users. Overall, results indicate that reward-based decision-making under risk may represent a risk factor for PG across substance users, with some variations in these relationships influenced by specific class of substance of abuse.
Jiang, Minghuan; You, Joyce Hs
2016-05-01
This study aimed to compare the clinical and economic outcomes of pharmacogenetic-guided (PG-guided) and platelet reactivity testing-guided antiplatelet therapy for patients with acute coronary syndrome undergoing percutaneous coronary intervention. A decision-analytic model was simulated including four antiplatelet strategies: universal clopidogrel 75 mg daily, universal alternative P2Y12 inhibitor (prasugrel or ticagrelor), PG-guided therapy, and platelet reactivity testing-guided therapy. PG-guided therapy was the preferred option with lowest cost (US$75,208) and highest quality-adjusted life years gained (7.6249 quality-adjusted life years). The base-case results were robust in sensitivity analysis. PG-guided antiplatelet therapy showed the highest probability to be preferred antiplatelet strategy for acute coronary syndrome patients with percutaneous coronary intervention.
Khaksar, Ghazale; Sayed Tabatabaei, Badraldin Ebrahim; Arzani, Ahmad; Ghobadi, Cyrus; Ebrahimie, Esmaeil
2015-01-01
Background Pomegranate fruit (Punica granatum L.) is a rich source of anthocyanin pigments resulting in vibrant colours and anti-oxidant contents. Although the intensity and pattern of anthocyanin biosynthesis in fruit are strongly influenced by R2R3-MYB transcription factors, little is known about the regulation and role of MYB in anthocyanin pathway of pomegranate. Objectives The present study was conducted to elucidate the relationship between the expression of MYB transcription factor and the anthocyanin accumulation during the colour development phase of pomegranate fruits. Materials and Methods In this work, R2R3-MYB transcription factor (PgMYB) was isolated and characterized from pomegranate skin through RACE-PCR. The expression of PgMYB gene was monitored in three distinct pomegranate accessions with distinctive skin colour and pattern by semi-quantitative RT-PCR. Results The results indicated a strong association between skin colour in mature pomegranate fruits with the PgMYB transcripts. The highest expression level of PgMYB gene was observed in Poost Siyah Yazd (dark purple skin) throughout the ripening process. Furthermore, comparison of PgMYB amino acid sequences with those of R2R3-MYB family in grapevine, eucalyptus, peach, cacao, populus and Arabidopsis demonstrated that this protein shares high similarity (75-85% amino acid identity) with their conserved MYB domain. Computational structure prediction of PgMYB showed that the three conserved amino acids (Asn, Lys and Lys) are present in the same position of the MYB domain. Conclusions It is speculated that PgMYB gene influences the fruit colour and could be used to improve the accumula-tion of anthocyanin pigments in the pomegranate fruit. PMID:28959277
NASA Astrophysics Data System (ADS)
Yue, Chao; Ciais, Philippe; Li, Wei
2018-02-01
Several modelling studies reported elevated carbon emissions from historical land use change (ELUC) by including bidirectional transitions on the sub-grid scale (termed gross land use change), dominated by shifting cultivation and other land turnover processes. However, most dynamic global vegetation models (DGVMs) that have implemented gross land use change either do not account for sub-grid secondary lands, or often have only one single secondary land tile over a model grid cell and thus cannot account for various rotation lengths in shifting cultivation and associated secondary forest age dynamics. Therefore, it remains uncertain how realistic the past ELUC estimations are and how estimated ELUC will differ between the two modelling approaches with and without multiple sub-grid secondary land cohorts - in particular secondary forest cohorts. Here we investigated historical ELUC over 1501-2005 by including sub-grid forest age dynamics in a DGVM. We run two simulations, one with no secondary forests (Sageless) and the other with sub-grid secondary forests of six age classes whose demography is driven by historical land use change (Sage). Estimated global ELUC for 1501-2005 is 176 Pg C in Sage compared to 197 Pg C in Sageless. The lower ELUC values in Sage arise mainly from shifting cultivation in the tropics under an assumed constant rotation length of 15 years, being 27 Pg C in Sage in contrast to 46 Pg C in Sageless. Estimated cumulative ELUC values from wood harvest in the Sage simulation (31 Pg C) are however slightly higher than Sageless (27 Pg C) when the model is forced by reconstructed harvested areas because secondary forests targeted in Sage for harvest priority are insufficient to meet the prescribed harvest area, leading to wood harvest being dominated by old primary forests. An alternative approach to quantify wood harvest ELUC, i.e. always harvesting the close-to-mature forests in both Sageless and Sage, yields similar values of 33 Pg C by both simulations. The lower ELUC from shifting cultivation in Sage simulations depends on the predefined forest clearing priority rules in the model and the assumed rotation length. A set of sensitivity model runs over Africa reveal that a longer rotation length over the historical period likely results in higher emissions. Our results highlight that although gross land use change as a former missing emission component is included by a growing number of DGVMs, its contribution to overall ELUC remains uncertain and tends to be overestimated when models ignore sub-grid secondary forests.
Domanin, Maurizio; Bissacco, Daniele; Le Van, Davide; Vergara, Christian
2018-03-01
The aim of the study was to provide, by means of computational fluid dynamics, a comparative analysis after carotid endarterectomy (CEA) between patch graft (PG) and primary closure (PC) techniques performed in real carotid geometries to identify disturbed flow conditions potentially involved in the development of restenosis. Eight carotid geometries in seven asymptomatic patients who underwent CEA were analyzed. In six cases (A-F), CEA was performed using PG closure; in two cases (G and H), PC was performed. Three-dimensional carotid geometries, derived from postoperative magnetic resonance angiography, were reconstructed, and a computational fluid dynamics analysis was performed. A virtual scenario with PC closure was designed in patients in whom PG was originally inserted and vice versa. This allowed us to compare for each patient hemodynamic effects in the PG and PC scenarios in terms of oscillatory shear index (OSI) and relative residence time (RRT), considered indicators of disturbed flow. For the six original PG cases, the mean averaged-in-space OSI was 0.07 ± 0.01 for PG and 0.03 ± 0.02 for virtual-PC (difference, 0.04 ± 0.01; P = .0016). The mean of the percentage of area (%A) with OSI >0.2 resulted in 10.08% ± 3.38% for PG and 3.80% ± 3.22% for virtual-PC (difference, 6.28 ± 1.91; P = .008). For the same cases, the mean of the averaged-in-space RRT resulted in 5.48 ± 3.40 1/Pa for PG and 2.62 ± 1.12 1/Pa for virtual-PC (difference, 2.87 ± 1.46; P = .097). The mean of %A RRT >4.0 1/Pa resulted in 26.53% ± 12.98% for PG and 9.95% ± 6.53% for virtual-PC (difference, 16.58 ± 5.93; P = .025). For the two original PC cases, the averaged-in-space OSIs were 0.02 and 0.04 for PC and 0.03 and 0.02 for virtual-PG; the %A OSIs >0.2 were 0.9% and 7.6% for PC and 3.0% and 2.2% for virtual-PG; the averaged-in-space RRTs were 1.8 and 2.0 1/Pa for PC and 2.9 and 1.9 1/Pa for virtual-PG; the %A RRTs >4.0 1/Pa were 6.8% and 9.8% for PC and 9.4% and 6.2% for virtual-PG. These results revealed generally higher disturbed flows in the PG configurations with respect to the PC ones. OSI and RRT values were generally higher in PG cases with respect to PC, especially for high carotids or when the arteriotomy is mainly at the bulb region. Thus, an elective use of patch should be considered to prevent disturbed flows. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
Vinetz, J M; Dave, S K; Specht, C A; Brameld, K A; Xu, B; Hayward, R; Fidock, D A
1999-11-23
Within hours after the ingestion of a blood meal, the mosquito midgut epithelium synthesizes a chitinous sac, the peritrophic matrix. Plasmodium ookinetes traverse the peritrophic matrix while escaping the mosquito midgut. Chitinases (EC 3.2.1.14) are critical for parasite invasion of the midgut: the presence of the chitinase inhibitor, allosamidin, in an infectious blood meal prevents oocyst development. A chitinase gene, PgCHT1, recently has been identified in the avian malaria parasite P. gallinaceum. We used the sequence of PgCHT1 to identify a P. falciparum chitinase gene, PfCHT1, in the P. falciparum genome database. PfCHT1 differs from PgCHT1 in that the P. falciparum gene lacks proenzyme and chitin-binding domains. PfCHT1 was expressed as an active recombinant enzyme in Escherichia coli. PfCHT1 shares with PgCHT1 a substrate preference unique to Plasmodium chitinases: the enzymes cleave tri- and tetramers of GlcNAc from penta- and hexameric oligomers and are unable to cleave smaller native chitin oligosaccharides. The pH activity profile of PfCHT1 and its IC(50) (40 nM) to allosamidin are distinct from endochitinase activities secreted by P. gallinaceum ookinetes. Homology modeling predicts that PgCHT1 has a novel pocket in the catalytic active site that PfCHT1 lacks, which may explain the differential sensitivity of PfCHT1 and PgCHT1 to allosamidin. PfCHT1 may be the ortholog of a second, as yet unidentified, chitinase gene of P. gallinaceum. These results may allow us to develop novel strategies of blocking human malaria transmission based on interfering with P. falciparum chitinase.
Vinetz, Joseph M.; Dave, Sanat K.; Specht, Charles A.; Brameld, Kenneth A.; Xu, Bo; Hayward, Rhian; Fidock, David A.
1999-01-01
Within hours after the ingestion of a blood meal, the mosquito midgut epithelium synthesizes a chitinous sac, the peritrophic matrix. Plasmodium ookinetes traverse the peritrophic matrix while escaping the mosquito midgut. Chitinases (EC 3.2.1.14) are critical for parasite invasion of the midgut: the presence of the chitinase inhibitor, allosamidin, in an infectious blood meal prevents oocyst development. A chitinase gene, PgCHT1, recently has been identified in the avian malaria parasite P. gallinaceum. We used the sequence of PgCHT1 to identify a P. falciparum chitinase gene, PfCHT1, in the P. falciparum genome database. PfCHT1 differs from PgCHT1 in that the P. falciparum gene lacks proenzyme and chitin-binding domains. PfCHT1 was expressed as an active recombinant enzyme in Escherichia coli. PfCHT1 shares with PgCHT1 a substrate preference unique to Plasmodium chitinases: the enzymes cleave tri- and tetramers of GlcNAc from penta- and hexameric oligomers and are unable to cleave smaller native chitin oligosaccharides. The pH activity profile of PfCHT1 and its IC50 (40 nM) to allosamidin are distinct from endochitinase activities secreted by P. gallinaceum ookinetes. Homology modeling predicts that PgCHT1 has a novel pocket in the catalytic active site that PfCHT1 lacks, which may explain the differential sensitivity of PfCHT1 and PgCHT1 to allosamidin. PfCHT1 may be the ortholog of a second, as yet unidentified, chitinase gene of P. gallinaceum. These results may allow us to develop novel strategies of blocking human malaria transmission based on interfering with P. falciparum chitinase. PMID:10570198
Neurogranin as a Cerebrospinal Fluid Biomarker for Synaptic Loss in Symptomatic Alzheimer Disease
Kester, Maartje I.; Teunissen, Charlotte E.; Crimmins, Daniel L.; Herries, Elizabeth M.; Ladenson, Jack. H.; Scheltens, Philip; van der Flier, Wiesje M.; Morris, John C.; Holtzman, David M.; Fagan, Anne M.
2015-01-01
IMPORTANCE Neurogranin (NGRN) seems to be a promising novel cerebrospinal fluid (CSF) biomarker for synaptic loss; however, clinical, and especially longitudinal, data are sparse. OBJECTIVE To examine the utility of NGRN, with repeated CSF sampling, for diagnosis, prognosis, and monitoring of Alzheimer disease (AD). DESIGN, SETTING, AND PARTICIPANTS Longitudinal study of consecutive patients who underwent 2 lumbar punctures between the beginning of 1995 and the end of 2010 within the memory clinic–based Amsterdam Dementia Cohort. The study included 163 patients: 37 cognitively normal participants (mean [SE] age, 64 [2] years; 38% female; and mean [SE] Mini-Mental State Examination [MMSE] score, 28 [0.3]), 61 patients with mild cognitive impairment (MCI) (mean [SE] age, 68 [1] years; 38% female; and mean [SE] MMSE score, 27 [0.3]), and 65 patients with AD (mean [SE] age, 65 [1] years; 45% female; and mean [SE] MMSE score, 22 [0.7]). The mean (SE) interval between lumbar punctures was 2.0 (0.1) years, and the mean (SE) duration of cognitive follow-up was 3.8 (0.2) years. Measurements of CSF NGRN levels were obtained in January and February 2014. MAIN OUTCOME AND MEASURE Levels of NGRN in CSF samples. RESULTS Baseline CSF levels of NGRN in patients with AD (median level, 2381 pg/mL [interquartile range, 1651-3416 pg/mL]) were higher than in cognitively normal participants (median level, 1712 pg/mL [interquartile range, 1206-2724 pg/mL]) (P = .04). Baseline NGRN levels were highly correlated with total tau and tau phosphorylated at threonine 181 in all patient groups (all P < .001), but not with Aβ42. Baseline CSF levels of NGRN were also higher in patients with MCI who progressed to AD (median level, 2842 pg/mL [interquartile range, 1882-3950 pg/mL]) compared with those with stable MCI (median level, 1752 pg/mL [interquartile range, 1024-2438 pg/mL]) (P = .004), and they were predictive of progression from MCI to AD (hazard ratio, 1.8 [95% CI, 1.1-2.9]; stratified by tertiles). Linear mixed-model analyses demonstrated that within-person levels of NGRN increased over time in cognitively normal participants (mean [SE] level, 90 [45] pg/mL per year; P < .05) but not in patients with MCI or AD. CONCLUSIONS AND RELEVANCE Neurogranin is a promising biomarker for AD because levels were elevated in patients with AD compared with cognitively normal participants and predicted progression from MCI to AD. Within-person levels of NGRN increased in cognitively normal participants but not in patients with later stage MCI or AD, which suggests that NGRN may reflect presymptomatic synaptic dysfunction or loss. PMID:26366630
Responses of human neutrophils to nicotine and/or Porphyromonas gingivalis.
Al-Shibani, Nouf K; Labban, Nawaf Y; Kowolik, Michael J; Ruby, John D; Windsor, L Jack
2011-10-01
Tobacco smoking is considered a major modifiable risk factor for periodontal disease. Nicotine is the addictive ingredient in tobacco and has been shown to affect multiple cellular processes. Neutrophils are the first line of host defense and are critical cells in the maintenance of periodontal health through their role in the control of bacteria, but they can also contribute to the progression of periodontal disease by the production and release of reactive oxygen species (ROS). Virulence factors from periodontal pathogens, such as Porphyromonas gingivalis (Pg), stimulate the respiratory burst of neutrophils. The objective of this study is to explore the oxidative activity of neutrophils when stimulated with Pg, nicotine, or both. Neutrophils were separated from buffy coats by the double dextran gradient method. The generation of ROS by neutrophils was determined using luminol-dependent chemiluminescence assays. The reaction was followed for 90 minutes, and the neutrophil activation was recorded as the total integrated energy output. The Pg and Pg plus nicotine groups had a significantly higher active and peak chemiluminescence than the nicotine group (all with P <0.0001). The Pg and Pg with nicotine groups were not significantly different (P = 0.90). In the presence of Pg, the nicotine did not further enhance the ROS release by the neutrophils, suggesting that the bacteria induced the maximum ROS release in this model system.
Evaluation of pectinolytic activities for oenological uses from psychrotrophic yeasts.
Sahay, S; Hamid, B; Singh, P; Ranjan, K; Chauhan, D; Rana, R S; Chaurse, V K
2013-08-01
Of the twenty-three morphotypes of yeasts isolated from soil capable of utilizing pectin as sole carbon source at 6°C, two yeast isolates, one psychrotolerant (PT1) and one psychrophilic (SPY11), were selected according to their ability to secrete pectinolytic enzymes under some oenological conditions (temperature 6 and 12°C and pH 3.5) and ability or inability to grow above 20°C, respectively. As compared to their optimal activity, the three pectinolytic enzymes viz., pectin methyl esterase (PME), endopolygalacturonase (endo-PG) and exopolygalacturonase (exo-PG) isolated and assayed at pH 3.5 from PT1 were found to retain 39, 60 and 60% activity at 12°C and 40, 79 and 74% activity at 28°C, respectively. Likewise, the enzymes PME and endo-PG at pH 3.5 from SPY11 displayed 46 and 86% activity at 12°C and 50 and 60% activity at 28°C, respectively. All these enzymes showed 20-90% of residual activity at pH 3.5 and 6°C. The yeast isolates PT1 and SPY11 were identified as Rhodotorula mucilaginosa and Cystofilobasidium capitatum, respectively, on the basis of morphological, physiological and molecular characteristics. This study presents the first report on pectinolytic activities under major oenological conditions from psychrotolerant isolate R. mucilaginosa PT1 and psychrophilic isolate C. capitatum SPY11. The cold-active pectinolytic enzymes (PME, endo-PG and exo-PG) from the newly isolated and identified psychrophilic yeast Cystofilobasidium capitatum SPY11 and psychrotolerant yeast Rhodotorula mucilaginosa PT1that exhibited 50-80% of their optimum activity under some major oenological conditions pH (3.5) and temperatures (6 and 12°C) could be applied to wine production and juice clarification at low temperature. The psychrotrophic yeasts themselves could be applied to cold process for the production of enzymes thus saving cost of energy and protecting process from contamination. © 2013 The Society for Applied Microbiology.
Rodríguez-Martín, Andrea; Acosta, Raquel; Liddell, Susan; Núñez, Félix; Benito, M José; Asensio, Miguel A
2010-04-01
The strain RP42C from Penicillium chrysogenum produces a small protein PgAFP that inhibits the growth of some toxigenic molds. The molecular mass of the protein determined by electrospray ionization mass spectrometry (ESI-MS) was 6 494Da. PgAFP showed a cationic character with an estimated pI value of 9.22. Upon chemical and enzymatic treatments of PgAFP, no evidence for N- or O-glycosylations was obtained. Five partial sequences of PgAFP were obtained by Edman degradation and by ESI-MS/MS after trypsin and chymotrypsin digestions. Using degenerate primers from these peptide sequences, a segment of 70bp was amplified by PCR from pgafp gene. 5'- and 3'-ends of pgafp were obtained by RACE-PCR with gene-specific primers designed from the 70bp segment. The complete pgafp sequence of 404bp was obtained using primers designed from 5'- and 3'-ends. Comparison of genomic and cDNA sequences revealed a 279bp coding region interrupted by two introns of 63 and 62bp. The precursor of the antifungal protein consists of 92 amino acids and appears to be processed to the mature 58 amino acids PgAFP. The deduced amino acid sequence of the mature protein shares 79% identity to the antifungal protein Anafp from Aspergillus niger. PgAFP is a new protein that belongs to the group of small, cysteine-rich, and basic proteins with antifungal activity produced by ascomycetes. Given that P. chrysogenum is regarded as safe mold commonly found in foods, PgAFP may be useful to prevent growth of toxigenic molds in food and agricultural products. Copyright (c) 2009 Elsevier Inc. All rights reserved.
Yang, Jianhua; Xu, Huanhuan; Wu, Shanshan; Ju, Bowei; Zhu, Dandan; Yan, Yao; Wang, Mei; Hu, Junping
2017-01-01
The primary aim of the present study was to develop a novel microemulsion (ME) formulation to deliver phenylethanoid glycoside (PG) for use in skin lighteners and sunscreens. The oil phase was selected on the basis of drug solubility, while the surfactant and cosurfactant were screened and selected on the basis of their solubilizing capacity and the efficiency with which they formed MEs. Pseudoternary phase diagrams were constructed to evaluate ME regions and five formulations of oil-in-water MEs were selected as vehicles. In vitro skin permeation experiments were performed to optimize the ME formulation and to evaluate its permeability in comparison to that of saline solution. The physicochemical properties of the optimized ME and the permeating ability of PG delivered by this ME were also investigated. The optimized ME formulation was composed of isopropyl myristate (7%, w/w), Cremorphor EL (21%, w/w), propylene glycol (7%, w/w) and water (65%, w/w). The cumulative amount of PG that permeated through excised mouse skin when carried by ME was ~1.68 times that when PG was carried by saline solution only. The cumulative amount of PG in the microemulsion (4149.650±37.3 µg·cm−2) was significantly greater than that of PG in the saline solution (2288.63±20.9 µg·cm−2). Furthermore, the permeability coefficient indicated that optimized microemulsion was a more efficient carrier for transdermal delivery of PG than the control solution (8.87±0.49 cm/hx10−3 vs. 5.41±0.12 cm/hx10−3). Taken together, the permeating ability of ME-carried PG was significantly increased compared with saline solution. PMID:28138704
Field information links permafrost carbon to physical vulnerabilities of thawing
NASA Astrophysics Data System (ADS)
Harden, Jennifer W.; Koven, Charles D.; Ping, Chien-Lu; Hugelius, Gustaf; David McGuire, A.; Camill, Phillip; Jorgenson, Torre; Kuhry, Peter; Michaelson, Gary J.; O'Donnell, Jonathan A.; Schuur, Edward A. G.; Tarnocai, Charles; Johnson, Kristopher; Grosse, Guido
2012-08-01
Deep soil profiles containing permafrost (Gelisols) were characterized for organic carbon (C) and total nitrogen (N) stocks to 3 m depths. Using the Community Climate System Model (CCSM4) we calculate cumulative distributions of active layer thickness (ALT) under current and future climates. The difference in cumulative ALT distributions over time was multiplied by C and N contents of soil horizons in Gelisol suborders to calculate newly thawed C and N. Thawing ranged from 147 PgC with 10 PgN by 2050 (representative concentration pathway RCP scenario 4.5) to 436 PgC with 29 PgN by 2100 (RCP 8.5). Organic horizons that thaw are vulnerable to combustion, and all horizon types are vulnerable to shifts in hydrology and decomposition. The rates and extent of such losses are unknown and can be further constrained by linking field and modelling approaches. These changes have the potential for strong additional loading to our atmosphere, water resources, and ecosystems.
Field information links permafrost carbon to physical vulnerabilities of thawing
Harden, Jennifer W.; Koven, Charles; Ping, Chien-Lu; Hugelius, Gustaf; McGuire, A. David; Camill, P.; Jorgenson, Torre; Kuhry, Peter; Michaelson, Gary; O'Donnell, Jonathan A.; Schuur, Edward A.G.; Tamocai, Charles; Johnson, Kevin; Grosse, G.
2012-01-01
Deep soil profiles containing permafrost (Gelisols) were characterized for organic carbon (C) and total nitrogen (N) stocks to 3m depths. Using the Community Climate System Model (CCSM4) we calculate cumulative probability functions (PDFs) for active layer depths under current and future climates. The difference in PDFs over time was multiplied by C and N contents of soil horizons in Gelisol suborders to calculate newly thawed C and N, Thawing ranged from 147 PgC with 10 PgN by 2050 (representative concentration pathway RCP scenario 4.5) to 436 PgC with 29 PgN by 2100 (RCP 8.5). Organic horizons that thaw are vulnerable to combustion, and all horizon types are vulnerable to shifts in hydrology and decomposition. The rates and extent of such losses are unknown and can be further constrained by linking field and modelling approaches. These changes have the potential for strong additional loading to our atmosphere, water resources, and ecosystems.
Tao, Yehan; Xue, Qingzhong; Liu, Zilong; Shan, Meixia; Ling, Cuicui; Wu, Tiantian; Li, Xiaofang
2014-06-11
First-principle density functional theory (DFT) calculation and molecular dynamic (MD) simulation are employed to investigate the hydrogen purification performance of two-dimensional porous graphene material (PG-ESX). First, the pore size of PG-ES1 (3.2775 Å) is expected to show high selectivity of H2 by DFT calculation. Then MD simulations demonstrate the hydrogen purification process of the PG-ESX membrane. The results indicate that the selectivity of H2 over several other gas molecules that often accompany H2 in industrial steam methane reforming or dehydrogenation of alkanes (such as N2, CO, and CH4) is sensitive to the pore size of the membrane. PG-ES and PG-ES1 membranes both exhibit high selectivity for H2 over other gases, but the permeability of the PG-ES membrane is much lower than the PG-ES1 membrane because of the smaller pore size. The PG-ES2 membrane with bigger pores demonstrates low selectivity for H2 over other gases. Energy barrier and electron density have been used to explain the difference of selectivity and permeability of PG-ESX membranes by DFT calculations. The energy barrier for gas molecules passing through the membrane generally increase with the decreasing of pore sizes or increasing of molecule kinetic diameter, due to the different electron overlap between gas and a membrane. The PG-ES1 membrane is far superior to other carbon membranes and has great potential applications in hydrogen purification, energy clean combustion, and making new concept membrane for gas separation.
Iasnikov, A A; Ponomarenko, S P
1976-05-01
Kinetics of co-oxidation of 1-benzen-3-carbamido-1,4-dihydropyridine (BDN) and phenylglyoxal (PG) with hydrogen peroxide is studied. Dimeric product (di-e11-benzen-5-carbamido-1,2-dihydropyridyl-2]) is found to be formed at pH 9, and quaternal pyridinium salt (BNA)--at pH 7. Molecular oxigen is determined to participate in the reaction at pH 7. Copper (II) ions catalyze this process. Significant catalytic effect of p-dinitrobenzen (p-DNB) is found. The reaction mechanism is postulated to form hydroperoxide from PG and hydrogen peroxide which are capable to split the hydrogen attom from dihydropyridine, molecular oxigen or p-DNB being an acceptor of the electrone. Hypothesis on separate transfer of hydrogen atom and electrone in biological systems are proposed.
NASA Astrophysics Data System (ADS)
Harrison, R. G.; Aplin, K. L.
Atmospheric electrical measurements provide proxy data from which historic smoke pollution levels can be determined. This approach is applied to infer autumnal Parisian smoke levels in the 1890s, based on atmospheric electric potential measurements made at the surface and the summit of the Eiffel Tower (48.7°N, 2.4°E). A theoretical model of the development of the autumn convective boundary layer is used to determine when local pollution effects dominated the Eiffel Tower potential measurements. The diurnal variation of the Eiffel Tower potential showed a single oscillation, but it differs from the standard oceanic air potential gradient (PG) variations during the period 09-17 UT, when the model indicates that the Eiffel Tower summit should be within the boundary layer. Outside these hours, the potential changes closely follow the clean air PG variation: this finding is used to calibrate the Eiffel Tower measurements. The surface smoke pollution concentration found during the morning maximum was 60±30 μg m -3, substantially lower than the values previously inferred for Kew in 1863. A vertical smoke profile was also derived using a combination of the atmospheric electrical data and boundary layer meteorology theory. Midday smoke concentration decreased with height from 60 μg m -3 at the surface to 15 μg m -3 at the top of the Eiffel Tower. The 19th century PG measurements in both polluted and clean Parisian air present a unique resource for European air pollution and atmospheric composition studies, and early evidence of the global atmospheric electrical circuit.
The Chicxulub impact at the K-Pg boundary - search for traces of the projectile
NASA Astrophysics Data System (ADS)
Deutsch, A.
2012-04-01
One of the most interesting problems in the context of the end-Cretaceous Chicxulub impact is the question after the whererabouts of the main mass of the projectile. The nature of this >10 km-sized Chicxulub projectile was constrained by an anomaly in the chromium isotope 54 in the K-Pg deposit at Stevens Klint, Denmark, to a carbonaceous chondrite of type CM2 [1]. About 1.5 % of the estimated mass of the projectile has been detected world-wide in the K-Pg boundary layer; mainly in the form of platinum group elements (PGE) as well as other siderophile elements (Ni, Co ... ). A contamination by or even a major contribution of other "projectile" elements to the K-Pg event bed was rarely proposed. The few examples in the literature (cf. compilation in [2, 3]) used rare earth elements (REE) distribution patterns that are slightly inconsistent with REE patterns typical for the upper continental crust (UCC). Ejecta consisting of UCC target rocks is expected to form the overwhelming mass of the ejecta. In most K-Pg layers, however, the ejecta is diluted or even totally masked by a component of more local origin and with features of high-energy deposition mechanisms. Numerical models [4] indicate a deposition of >500km3 projectile material, corresponding to >2 x 10exp9 tons of mainly silica, iron, and magnesium in the K-Pg event bed. Detecting the "meteoritic" origin of these major elements, however, in a matrix of siliceous detritus, is practically impossible. Recent LA-ICP-MS analyses show that siliceous impact spherules - hydrated glass or altered to chlorite - in the Chicxulub event bed at various locations (e.g., Shell Creek, La Lajilla, La Popa) have REE patterns that are flat and un-fractionated, corresponding quite well to a typical CI-pattern. The REE abundances are chondritic to sub-chondritic. Mixing calculations indicate that the maximum REE contribution of UCC material to the REE budget of these spherules is on the order of 2 %, but usually much less. These flat REE patterns cannot originate from any known alteration process; they truly reflect a "meteoritic" component in the spherules. Accepting this fact, a certain amount of the siliceous host material (i.e., the spherules) must consist also of projectile material. Depending on the sampling site, the spherules with the flat REE distribution patterns amount to between 10 and ~70 vol% of the Chicxulub event bed. The widespread occurrence of this projectile matter in the K-Pg event bed reconciles observations with impact models [4]. Ref. [1] Trinquier A. et al. (2006) EPSL 241, 780-788. [2] Smit J. (1999) Ann. Rev. Earth Planet. Sci. 27, 75-113. [3] Schulte P. et al. (2010) Science 327, 1214-1218. [4] Artemieva N. and Morgan J. (2009) Icarus 201, 768-780.
Global fire emissions estimates during 1997-2016
NASA Astrophysics Data System (ADS)
van der Werf, Guido R.; Randerson, James T.; Giglio, Louis; van Leeuwen, Thijs T.; Chen, Yang; Rogers, Brendan M.; Mu, Mingquan; van Marle, Margreet J. E.; Morton, Douglas C.; Collatz, G. James; Yokelson, Robert J.; Kasibhatla, Prasad S.
2017-09-01
Climate, land use, and other anthropogenic and natural drivers have the potential to influence fire dynamics in many regions. To develop a mechanistic understanding of the changing role of these drivers and their impact on atmospheric composition, long-term fire records are needed that fuse information from different satellite and in situ data streams. Here we describe the fourth version of the Global Fire Emissions Database (GFED) and quantify global fire emissions patterns during 1997-2016. The modeling system, based on the Carnegie-Ames-Stanford Approach (CASA) biogeochemical model, has several modifications from the previous version and uses higher quality input datasets. Significant upgrades include (1) new burned area estimates with contributions from small fires, (2) a revised fuel consumption parameterization optimized using field observations, (3) modifications that improve the representation of fuel consumption in frequently burning landscapes, and (4) fire severity estimates that better represent continental differences in burning processes across boreal regions of North America and Eurasia. The new version has a higher spatial resolution (0.25°) and uses a different set of emission factors that separately resolves trace gas and aerosol emissions from temperate and boreal forest ecosystems. Global mean carbon emissions using the burned area dataset with small fires (GFED4s) were 2.2 × 1015 grams of carbon per year (Pg C yr-1) during 1997-2016, with a maximum in 1997 (3.0 Pg C yr-1) and minimum in 2013 (1.8 Pg C yr-1). These estimates were 11 % higher than our previous estimates (GFED3) during 1997-2011, when the two datasets overlapped. This net increase was the result of a substantial increase in burned area (37 %), mostly due to the inclusion of small fires, and a modest decrease in mean fuel consumption (-19 %) to better match estimates from field studies, primarily in savannas and grasslands. For trace gas and aerosol emissions, differences between GFED4s and GFED3 were often larger due to the use of revised emission factors. If small fire burned area was excluded (GFED4 without the s
for small fires), average emissions were 1.5 Pg C yr-1. The addition of small fires had the largest impact on emissions in temperate North America, Central America, Europe, and temperate Asia. This small fire layer carries substantial uncertainties; improving these estimates will require use of new burned area products derived from high-resolution satellite imagery. Our revised dataset provides an internally consistent set of burned area and emissions that may contribute to a better understanding of multi-decadal changes in fire dynamics and their impact on the Earth system. GFED data are available from http://www.globalfiredata.org.
Temperature Rise and Allowable Carbon Emissions for the RCP2.6 Scenario
NASA Astrophysics Data System (ADS)
Tachiiri, K.; Hargreaves, J. C.; Annan, J. D.; Huntingford, C.; Kawamiya, M.
2012-12-01
Climate research centres are running Earth System Models (ESMs) forced by Representative Concentration Pathway (RCP) scenarios. While these GCM studies increase process based knowledge, the number of simulations is small, making it difficult to interpret the resulting distribution of responses in a probabilistic way. We use a probabilistic framework to estimate the range of future temperature change and allowable emissions for a low mitigation CO2 concentration pathway RCP 2.6. Uncertainty is initially estimated by allowing modelled equilibrium climate sensitivity, aerosol forcing and intrinsic physical and biogeochemical processes to vary within widely accepted ranges. Results are then further constrained by extensive use of contemporary measurements. Despite this, the resulting range of temperatures for RCP 2.6 remains large. The predicted peak global temperature increase, reached around 2100, from pre-industrial is 0.8 - 1.9 K and 1.0 - 1.9 K (95% range) for the unconstrained and the constrained cases, respectively. Allowable emissions at the time of peak emission period is projected as 6.0 - 10.8 PgC yr-1 and 7.4 - 10.2 PgC yr-1 for each case. After year 2100, negative net emissions are required with a probability of some 84 %, and related uncertainty in cumulative emissions is large.
Effect of interannual climate variability on carbon storage in Amazonian ecosystems
Tian, H.; Melillo, J.M.; Kicklighter, D.W.; McGuire, David A.; Helfrich, J. V. K.; Moore, B.; Vorosmarty, C.J.
1998-01-01
The Amazon Basin contains almost one-half of the world's undisturbed tropical evergreen forest as well as large areas of tropical savanna. The forests account for about 10 per cent of the world's terrestrial primary productivity and for a similar fraction of the carbon stored in land ecosystems, and short-term field measurements suggest that these ecosystems are globally important carbon sinks. But tropical land ecosystems have experienced substantial interannual climate variability owing to frequent El Nino episodes in recent decades. Of particular importance to climate change policy is how such climate variations, coupled with increases in atmospheric CO2 concentration, affect terrestrial carbon storage. Previous model analyses have demonstrated the importance of temperature in controlling carbon storage. Here we use a transient process-based biogeochemical model of terrestrial ecosystems to investigate interannual variations of carbon storage in undisturbed Amazonian ecosystems in response to climate variability and increasing atmospheric CO2 concentration during the period 1980 to 1994. In El Nino years, which bring hot, dry weather to much of the Amazon region, the ecosystems act as a source of carbon to the atmosphere (up to 0.2 petagrams of carbon in 1987 and 1992). In other years, these ecosystems act as a carbon sink (up to 0.7 Pg C in 1981 and 1993). These fluxes are large; they compare to a 0.3 Pg C per year source to the atmosphere associated with deforestation in the Amazon Basin in the early 1990s. Soil moisture, which is affected by both precipitation and temperature, and which affects both plant and soil processes, appears to be an important control on carbon storage.
Kim, Hae Su; Lee, Ji Yun; Lim, Sung Hee; Cho, Jaewon; Kim, Seok Jin; Jang, Jun Ho; Kim, Won Seog; Jung, Chul Won; Kim, Kihyun
2017-04-01
Disease-related weight loss is relatively common in patients with newly diagnosed multiple myeloma (MM), but limited data exist regarding the effects of nutritional status on survival. The aim of this study was to assess the relationship between malnutrition (as measured by Patient-Generated Subjective Global Assessment [PG-SGA]) and clinical characteristics of patients with MM, and to investigate the association between the PG-SGA score before chemotherapy and overall survival in MM patients. Using the PG-SGA score, we retrospectively explored the effect of malnutrition on the survival of Asian patients with MM. We divided 216 patients with MM into three groups based on their PG-SGA scores. Of these patients 23% (n = 50) had PG-SGA scores ≥9, indicating severe malnutrition requiring specialist nutrition intervention. Body mass index and serum hemoglobin were independently associated with PG-SGA scores (P < 0.05). The median survival time was not reached in nourished patients with PG-SGA scores of 0 to 3, 58.7 mo in moderately malnourished patients with PG-SGA scores of 4 to 8, and 35 mo in severely malnourished patients with PG-SGA scores ≥9 (P = 0.001). Multivariate analysis revealed that PG-SGA scores ≥9 compared with PG-SGA scores of 0 to 3 (hazard ratio [HR], 2.347; 95% confidence interval [CI], 1.271-4.334; P = 0.006), International Staging System (ISS) stage III compared with ISS stage I (HR, 2.360; 95% CI, 1.271-4.379; P = 0.007), and autologous stem cell transplantation (HR, 0.388; 95% CI, 0.248-0.606; P < 0.001) were associated with overall survival. A higher PG-SGA score before chemotherapy was associated with reduced survival among patients with MM. Nutritional evaluation should be an integral part of the clinical assessment of MM patients, and the PG-SGA score would be an appropriate tool to evaluate nutritional status. Copyright © 2016 Elsevier Inc. All rights reserved.
Hauschild, Gregor; Geburek, Florian; Gosheger, Georg; Eveslage, Maria; Serrano, Daniela; Streitbürger, Arne; Johannlükens, Sara; Menzel, Dirk; Mischke, Reinhard
2017-01-05
The increasing interest in platelet-rich plasma (PRP) based therapies is as yet accompanied by inconsistent information regarding nearly all aspects of handling and application. Among these storage stability of processed platelet-rich products may be the basis for a more flexible application mode. The objective of this study was (1) to estimate the storage stability of growth factors platelet derived growth factor BB (PDGF-BB) and transforming growth factor ß1 (TGF-ß1) in both, a single-step softspin centrifugation-based pure-PRP (P-PRP, ACP®), and a gravity filtration system-based leukocyte-rich-PRP (L-PRP, E-PET), over a six hours time span after preparation at room temperature and (2) to identify possible factors influencing these growth factor concentrations in an equine model. Growth factor concentrations remained stable over the entire investigation period in L-PRP as well as P-PRP preparations revealing a mean of 3569 pg/ml PDGF-BB for E-PET and means of 1276 pg/ml PDGF-BB and 5086 pg/ml TGF-ß1 for ACP®. Pearson correlations yielded no significant impact of whole blood platelet (PLT), white blood cell (WBC) and red blood cell (RBC) counts on resulting cytokine values. In case of ACP® no significant dependencies between PLT, WBC and RBC counts of the processed platelet-rich product and resulting cytokine content occurred with exception of TGF-ß1 concentrations showing a strong correlation with the WBC content. PDGF-BB content of E-PET preparations showed a strong positive correlation with PLT and a strong negative with WBC of these preparations but not with RBC. L-PRP ad modum E-PET and P-PRP ad modum ACP® are applicable over at least a six hours time span at room temperature without loss of growth factor content. Based on the results of this study factors influencing the resulting growth factor concentrations still remain questionable. Additional studies implicating a further standardization of preparation protocols are necessary to identify consistent impact on cytokine content after PRP processing.
Impact of mesophyll diffusion on estimated global land CO 2 fertilization
Sun, Ying; Gu, Lianhong; Dickinson, Robert E.; ...
2014-10-13
In C 3 plants, CO 2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO 2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and so overestimate CO 2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO 2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO 2 fertilization effect (CFE) for global gross primary production (GPP) from 915 PgC to 1057 PgC for the period of 1901 to 2010. This increase represents a 16% correction, large enough to explain the persistent overestimation of growth ratesmore » of historical atmospheric CO 2 by Earth System Models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC yr -1ppm -1. This finding implies that the contemporary terrestrial biosphere is more CO 2-limited than previously thought.« less
Urban-rural differences in atmospheric mercury speciation
NASA Astrophysics Data System (ADS)
Liu, Bian; Keeler, Gerald J.; Timothy Dvonch, J.; Barres, James A.; Lynam, Mary M.; Marsik, Frank J.; Morgan, Joy Taylor
2010-05-01
Measurements of gaseous elemental mercury (GEM), particulate mercury (Hg p), and reactive gaseous mercury (RGM) were concurrently recorded at an urban site in Detroit and a rural site in Dexter, both in Michigan for the calendar year 2004. Their average concentrations (±standard deviation) for the urban area were 2.5 ± 1.4 ng m -3, 18.1 ± 61.0 pg m -3, and 15.5 ± 54.9 pg m -3, respectively, while their rural counterparts were 1.6 ± 0.6 ng m -3, 6.1 ± 5.5 pg m -3, and 3.8 ± 6.6 pg m -3, respectively. The medians of urban-to-rural ratios of Hg concentrations indicate approximately 1-fold, 2-fold, and 3-fold gradients between Detroit and Dexter for GEM, Hg p, and RGM, respectively. The urban-rural differences in Hg also varied considerably on different temporal scales and with wind flow patterns, which was most evident in RGM. Our results show that while Hg at both sites was impacted by regional sources, meteorological conditions, and photochemical transformations, the extent of variations in the observed urban-to-rural gradients, particularly in RGM, cannot be fully accounted for by these processes. Both analyses of the annual data and case studies indicate that the more variable and episodic nature of Hg, particularly RGM, seen in Detroit compared with Dexter, was the result of direct impact from local anthropogenic sources.
Wu, Nian; Zhang, Yu; Ye, Xingqian; Hu, Yaqin; Ding, Tian; Chen, Shiguo
2016-08-20
Fucosylated chondroitin sulfates (fCSs) are glycosaminoglycans extracted from sea cucumbers, consisting of chondroitin sulfate E (CSE) backbones and sulfated fucose branches. The biological properties of fCSs could be affected by the sulfation pattern of their fucose branches. In the present study, two fCSs were isolated from sea cucumbers Isostichopus badionotus (fCS-Ib) and Pearsonothuria graeffei (fCS-Pg). Their monosaccharide compositions of glucuronic acid (GlcA), N-acetylgalactosamine (GalNAc), fucose (Fuc) and sulfate were at similar molar ratio with 1.0/0.7/0.9/3.1 for fCS-Ib and 1.0/0.8/1.5/2.6 for fCS-Pg. The two fCSs have different sulfation patterns on their fucose branches, fCS-Pg with 3,4-O-disulfation while fCS-Ib with 2,4-O-disulfation. Their antihyperlipidemic effects were compared using a high-fat high-fructose diet (HFFD)-fed C57BL/6J mice model. Both fCS-Ib and fCS-Pg had significant effects on lipid profile improvement, liver protection, blood glucose diminution and hepatic glycogen synthesis. Specifically, fCS-Pg with 3,4-O-disulfation fucose branches was more effective in reduction of blood cholesterol (TC), low density lipoprotein (LDL) and atherogenic index (AI). Our results indicate that both fCSs, especially fCS-Pg, could be used as a potential anti-hyperlipidemic drug. Copyright © 2016. Published by Elsevier Ltd.
Grewal, Jasmine; McKelvie, Robert S; Persson, Hans; Tait, Peter; Carlsson, Jonas; Swedberg, Karl; Ostergren, Jan; Lonn, Eva
2008-09-15
More than 40% of patients hospitalized with heart failure have preserved left ventricular ejection fraction (HF-PLVEF) and are at high risk for cardiovascular (CV) events. The purpose of this study was to determine the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) in predicting CV outcomes in patients with HF-PLVEF. Participants with an ejection fraction >40% in the prospective CHARM Echocardiographic Substudy were included in this analysis. Plasma NT-proBNP levels were measured, and 2 cut-offs were selected prospectively at 300 pg/ml and 600 pg/ml. BNP cut-off was set at 100 pg/ml. Clinical characteristics were recorded, and systolic and diastolic function were evaluated by echocardiography. The primary substudy outcome was the composite of CV mortality, hospitalization for heart failure, and myocardial infarction or stroke. A total of 181 patients were included, and there were 17 primary CV events (9.4%) during a median follow-up time of 524 days. In a model including clinical characteristics, echocardiographic measures, and BNP or NT-proBNP, the composite CV event outcome was best predicted by NT-proBNP >300 pg/ml (hazard ratio 5.8, 95% confidence intervals [CI] 1.3 to 26.4, p = 0.02) and moderate or severe diastolic dysfunction on echocardiography. When NT-proBNP >600 pg/ml was used in the model, it was the sole independent predictor of primary CV events (hazard ratio 8.0, 95% CI 2.6 to 24.8, p = 0.0003) as was BNP >100 pg/ml (hazard ratio 3.1, 95% CI 1.2 to 8.2, p = 0.02) in the BNP model. In conclusion, both elevated NT-proBNP and BNP are strong independent predictors of clinical events in patients with HF-PLVEF.
Chakraborty, Paromita; Selvaraj, Sakthivel; Nakamura, Masafumi; Prithiviraj, Balasubramanian; Cincinelli, Alessandra; Bang, John J
2018-04-15
Growth of informal electronic waste (e-waste) recycling sector is an emerging problem for India. The presence of halogenated compounds in e-wastes may result in the formation of persistent organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during recycling processes. We therefore investigated PCBs and PCDD/Fs in surface soils explicitly from the informal e-waste recycling sites and nearby open dumpsites of major metropolitan cities from four corners of India, viz., New Delhi (North), Kolkata (East), Mumbai (West) and Chennai (South). In the informal e-waste recycling sites, the range of Σ 26 PCBs (0.4-488ng/g) and ƩPCDD/Fs (1.0-10.6ng/g) were higher than Ʃ 26 PCBs (0.3-21ng/g) and ƩPCDD/Fs (0.15-7.3ng/g) from open dumpsites. In the e-waste sites, ƩPCDDs were found with increasing trend from ƩTetraCDD to OctaCDD, whereas ƩPCDFs showed a reverse trend. The dominance of PCDF congeners and maximum toxicity equivalents (TEQ) for both PCDDs (17pg TEQ/g) and PCDFs (82pg TEQ/g) at Mandoli in New Delhi has been related to intensive precious metal recovery process using acid bath. Among dumpsites, highest TEQ for PCDD/Fs was observed at Kodangaiyur dumpsite of Chennai (CN DS -02, 45pg TEQ/g). Positive Matrix Factorization (PMF) model identified distinct congener pattern based on the functional activities, such as e-waste dismantling, shredding, precious metal recovery and open burning in dumpsites. E-waste metal recovery factor was loaded with 86-91% of PCB-77, -105, -114, -118 and 30% of PCB-126, possibly associated with the burning of wires during the copper extraction process. Almost 70% of the Ʃ 26 PCB concentrations was comprised of the dioxin-like PCB congeners with a maximum concentration of 437ng/g at New Moore market in Chennai, followed by Wire Lane (102ng/g), in Mumbai. We speculate that PCB-126 might have resulted from combustion of plastic materials in e-waste stream and dumped waste. Copyright © 2017 Elsevier B.V. All rights reserved.
Health risk assessment of PCDD/F emissions from a hazardous and medical waste incinerator in Turkey.
Karademir, Aykan
2004-10-01
A multimedia risk assessment procedure was conducted to determine the fate and transport of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) emissions from the Izmit Hazardous and Medical Waste Incinerator (IZAYDAS) in Turkey and their potential health risks. Congener concentrations in ambient air and their deposition rates were determined by an air dispersion model (ISCST3). Their transfer to some plant groups and animal tissues was predicted by food chain modeling. Exposure scenarios were produced based on three receptor groups (urban, semiurban, and rural) and five subgroups determined according to ages. Daily intakes of PCDD/Fs via exposure pathways were determined based on three different emission scenarios for each group and subgroup. Estimated incremental PCDD/F doses caused by the incinerator emissions in central-tendency scenario were computed as between 2.31 x 10(-6) and 0.008 pg TEQ kg(-1) bodyweight (bw) day(-1) on average for all the receptors other than infants in all the settings, while the range was 3.01 x 10(-5)-0.081 pg TEQ kg(-1) bw day(-1) for infants. Sensitivity analysis showed that the consumption of vegetal products and their locally grown fractions are the most significant parameters in the exposure to PCDD/Fs in the area.
Discovery and Asteroseismological Analysis of the Pulsating sdB Star PG 0014+067
NASA Astrophysics Data System (ADS)
Brassard, P.; Fontaine, G.; Billères, M.; Charpinet, S.; Liebert, James; Saffer, R. A.
2001-12-01
We report the discovery of low-amplitude, short-period, multiperiodic luminosity variations in the hot B subdwarf PG 0014+067. This star was selected as a potential target in the course of our ongoing survey to search for pulsators of the EC 14026 type. Our model atmosphere analysis of the time-averaged Multiple Mirror Telescope (MMT) optical spectrum of PG 0014+067 indicates that this star has Teff=33,550+/-380 K and logg=5.77+/-0.10, which places it right in the middle of the theoretical EC 14026 instability region in the logg-Teff plane. A standard analysis of our Canada-France-Hawaii Telescope (CFHT) light curve reveals the presence of at least 13 distinct harmonic oscillations with periods in the range 80-170 s. Fine structure (closely spaced frequency doublets) is observed in three of these oscillations, and five high-frequency peaks due to nonlinear cross frequency superpositions of the basic oscillations are also possibly seen in the Fourier spectrum. The largest oscillation has an amplitude ~=0.22% of the mean brightness of the star, making PG 0014+067 the EC 14026 star with the smallest intrinsic amplitudes so far. On the basis of the 13 observed periods, we carry out a detailed asteroseismological analysis of the data starting with an extensive search in parameter space for a model that could account for the observations. To make this search efficient, objective, and reliable, we use a newly developed period matching technique based on an optimization algorithm. This search leads to a model that can account remarkably well for the 13 observed periods in the light curve of PG 0014+067. A detailed comparison of the theoretical period spectrum of this optimal model with the distribution of the 13 observed periods leads to the realization that 10 other pulsations, with lower amplitudes than the threshold value used in our standard analysis, are probably present in the light curve of PG 0014+067. Altogether, we tentatively identify 23 distinct pulsation modes in our target star (counting the frequency doublets referred to above as single modes). These are all low-order acoustic modes with adjacent values of k and with l=0, 1, 2, and 3. They define a band of unstable periods, in close agreement with nonadiabatic pulsation theory. Furthermore, the average relative dispersion between the 23 observed periods and the periods of the corresponding 23 theoretical modes of the optimal model is only ~=0.8%, a remarkable achievement by asteroseismological standards. On the basis of our analysis, we infer that the global structural parameters of PG 0014+067 are logg=5.780+/-0.008, Teff=34,500K+/-2690 K, M*/Msolar=0.490+/-0.019, log(Menv/M*)=-4.31+/-0.22, and R/Rsolar=0.149+/-0.004. If we combine these estimates of the surface gravity, total mass, and radius with our value of the spectroscopic temperature (which is more accurately evaluated than its asteroseismological counterpart, in direct contrast to the surface gravity), we also find that PG 0014+067 has a luminosity L/Lsolar=25.5+/-2.5, has an absolute visual magnitude MV=4.48+/-0.12, and is located at a distance d=1925+/-195 pc (using V=15.9+/-0.1). If we interpret the fine structure (frequency doublets) observed in three of the 23 pulsations in terms of rotational splitting, we further find that PG 0014+067 rotates with a period of 29.2+/-0.9 hr and has a maximum rotational broadening velocity of Vsini<~6.2+/-0.4 km s-1. Based on observations gathered at the Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, the Centre National de la Recherche Scientifique de France, and the University of Hawaii.
Bouhrara, Mustapha; Reiter, David A; Sexton, Kyle W; Bergeron, Christopher M; Zukley, Linda M; Spencer, Richard G
2017-11-01
We applied our recently introduced Bayesian analytic method to achieve clinically-feasible in-vivo mapping of the proteoglycan water fraction (PgWF) of human knee cartilage with improved spatial resolution and stability as compared to existing methods. Multicomponent driven equilibrium single-pulse observation of T 1 and T 2 (mcDESPOT) datasets were acquired from the knees of two healthy young subjects and one older subject with previous knee injury. Each dataset was processed using Bayesian Monte Carlo (BMC) analysis incorporating a two-component tissue model. We assessed the performance and reproducibility of BMC and of the conventional analysis of stochastic region contraction (SRC) in the estimation of PgWF. Stability of the BMC analysis of PgWF was tested by comparing independent high-resolution (HR) datasets from each of the two young subjects. Unlike SRC, the BMC-derived maps from the two HR datasets were essentially identical. Furthermore, SRC maps showed substantial random variation in estimated PgWF, and mean values that differed from those obtained using BMC. In addition, PgWF maps derived from conventional low-resolution (LR) datasets exhibited partial volume and magnetic susceptibility effects. These artifacts were absent in HR PgWF images. Finally, our analysis showed regional variation in PgWF estimates, and substantially higher values in the younger subjects as compared to the older subject. BMC-mcDESPOT permits HR in-vivo mapping of PgWF in human knee cartilage in a clinically-feasible acquisition time. HR mapping reduces the impact of partial volume and magnetic susceptibility artifacts compared to LR mapping. Finally, BMC-mcDESPOT demonstrated excellent reproducibility in the determination of PgWF. Published by Elsevier Inc.
NASA Astrophysics Data System (ADS)
Mohammadi-Ghaleni, Mahdi
The Sun has long been the most important energy source for planet Earth. Sunlight offers the potential to function as a source of clean, renewable energy; photovoltaic (PV) cells have been designed to tap into this abundant solar energy to generate electricity. Organic photovoltaic (OPV) devices show promise as technologies capable of lightweight, low cost and flexible alternatives to traditional silicon PV but the nature of conjugated organic and polymeric semiconductors have limited performance and, therefore, application. However, recent advances have shown that the addition of pristine graphene (PG) to the active layer of OPV devices can yield three-fold performance improvements in blends of P3HT (poly(3-hexylthiophene-2,5-diyl) & PCBM (phenyl C 61 butyric acid methyl ester) and, later, in all-polymer blends of P3HT & F8BT (poly(9,9-dioctylfluorene-alt-benzothiadiazole). In both OPV systems, increased performance is believed to be due to high charge carrier mobility imparted by the PG additive to the composite active layer blend. In this work, the effect of addition of PG to the active layer blend of P3HT & PCPDTBT (poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)]) systems was investigated. PV devices were designed, fabricated and tested using standard processing methods and testing procedures. Although PG increased OPV device performance relative to samples without PG, power conversion efficiency (eta) on an absolute scale was lower than expected despite the otherwise complementary properties of these materials. Based on the literature, the low performance of these devices was hypothesized to result from non-ideal active layer morphology, lacking charge carried percolation pathways to the electrodes. Small angle neutron scattering (SANS) was employed to probe the active layer morphology in polymer blend films similar to the active layers of the cells. Deuterated P3HT (d-P3HT) was used to exploit the large scattering length density (SLD) contrast between hydrogen and deuterium. Rigorous analysis of the SANS data allowed the nanostructure to be determined and a model of disk-like d-P3HT crystallites dispersed in a matrix of the amorphous polymers was constructed. This structure shows limited interfacial area for exciton dissociation and exhibits a lack of charge percolation pathways to the electrodes. Morphological insight offered by SANS analysis along with literature review allowed higher performance all-polymer photovoltaic cells to be designed and tested using the same semiconducting polymers. By introducing a co-solvent and modifying the thermal annealing procedure, significant performance gains were realized for subsequent devices. The increased performance observed following the change in procedure is believed to be due to enhanced active layer morphology and formation of a bulk heterojunction (BHJ) structure, to be studied in future work. Although there is room for further performance gains in P3HT-PCPDTBT devices as well as application to other OPV systems in future work, the methods, results and discussion presented here highlight the importance of structure-property relationships in all-polymer photovoltaic cells.
Ultrasensitive interdigitated capacitance immunosensor using gold nanoparticles.
Alizadeh Zeinabad, Hojjat; Ghourchian, Hedayatollah; Falahati, Mojtaba; Fathipour, Morteza; Azizi, Marzieh; Boutorabi, Seyed Mehdi
2018-06-29
Immunosensors based on interdigitated electrodes (IDEs), have recently demonstrated significant improvements in the sensitivity of capacitance detection. Herein, a novel type of highly sensitive, compact and portable immunosensor based on a gold interdigital capacitor has been designed and developed for the rapid detection of hepatitis B surface antigen (HBsAg). To improve the efficiency of antibody immobilization and time-saving, a self-assembled monolayer (SAM) of 2-mercaptoethylamine film was coated on IDEs. Afterwards, carboxyl groups on primary antibodies were activated through 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and were immobilized on amino-terminated SAM for better control of the oriented immobilization of antibodies on gold IDEs. In addition, gold nanoparticles conjugated with a secondary antibody were used to enhance the sensitivity. Under optimal conditions, the immunosensor exhibited the sensitivity of 0.22 nF.pg ml -1 , the linear range from 5 pg ml -1 to 1 ng ml -1 and the detection limit of 1.34 pg ml -1 , at a signal-to-noise ratio of 3.
Ultrasensitive interdigitated capacitance immunosensor using gold nanoparticles
NASA Astrophysics Data System (ADS)
Alizadeh Zeinabad, Hojjat; Ghourchian, Hedayatollah; Falahati, Mojtaba; Fathipour, Morteza; Azizi, Marzieh; Boutorabi, Seyed Mehdi
2018-06-01
Immunosensors based on interdigitated electrodes (IDEs), have recently demonstrated significant improvements in the sensitivity of capacitance detection. Herein, a novel type of highly sensitive, compact and portable immunosensor based on a gold interdigital capacitor has been designed and developed for the rapid detection of hepatitis B surface antigen (HBsAg). To improve the efficiency of antibody immobilization and time-saving, a self-assembled monolayer (SAM) of 2-mercaptoethylamine film was coated on IDEs. Afterwards, carboxyl groups on primary antibodies were activated through 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and were immobilized on amino-terminated SAM for better control of the oriented immobilization of antibodies on gold IDEs. In addition, gold nanoparticles conjugated with a secondary antibody were used to enhance the sensitivity. Under optimal conditions, the immunosensor exhibited the sensitivity of 0.22 nF.pg ml–1, the linear range from 5 pg ml‑1 to 1 ng ml–1 and the detection limit of 1.34 pg ml‑1, at a signal-to-noise ratio of 3.
Interannual variability of the atmospheric CO2 growth rate: roles of precipitation and temperature
NASA Astrophysics Data System (ADS)
Wang, Jun; Zeng, Ning; Wang, Meirong
2016-04-01
The interannual variability (IAV) in atmospheric CO2 growth rate (CGR) is closely connected with the El Niño-Southern Oscillation. However, sensitivities of CGR to temperature and precipitation remain largely uncertain. This paper analyzed the relationship between Mauna Loa CGR and tropical land climatic elements. We find that Mauna Loa CGR lags precipitation by 4 months with a correlation coefficient of -0.63, leads temperature by 1 month (0.77), and correlates with soil moisture (-0.65) with zero lag. Additionally, precipitation and temperature are highly correlated (-0.66), with precipitation leading by 4-5 months. Regression analysis shows that sensitivities of Mauna Loa CGR to temperature and precipitation are 2.92 ± 0.20 PgC yr-1 K-1 and -0.46 ± 0.07 PgC yr-1 100 mm-1, respectively. Unlike some recent suggestions, these empirical relationships favor neither temperature nor precipitation as the dominant factor of CGR IAV. We further analyzed seven terrestrial carbon cycle models, from the TRENDY project, to study the processes underlying CGR IAV. All models capture well the IAV of tropical land-atmosphere carbon flux (CFTA). Sensitivities of the ensemble mean CFTA to temperature and precipitation are 3.18 ± 0.11 PgC yr-1 K-1 and -0.67 ± 0.04 PgC yr-1 100 mm-1, close to Mauna Loa CGR. Importantly, the models consistently show the variability in net primary productivity (NPP) dominates CGR, rather than heterotrophic respiration. Because previous studies have proved that NPP is largely driven by precipitation in tropics, it suggests a key role of precipitation in CGR IAV despite the higher CGR correlation with temperature. Understanding the relative contribution of CO2 sensitivity to precipitation and temperature has important implications for future carbon-climate feedback using such ''emergent constraint''.
Schwan, Adrian L.; Singh, Suneel P.; Davy, Jason A.; Waring, Alan J.; Gordon, Larry M.; Walther, Frans J.; Wang, Zhengdong; Notter, Robert H.
2012-01-01
This paper reports the chemical synthesis and purification of a novel phospholipase-resistant C16:0, C16:1 diether phosphonoglycerol with structural analogy to ester-linked anionic phosphatidylglycerol (PG) in endogenous pulmonary surfactant. This diether phosphonoglycerol (PG 1) is studied for phospholipase A2 (PLA2) resistance and for surface activity in synthetic exogenous surfactants combined with Super Mini-B (S-MB) peptide and DEPN-8, a previously-reported diether phosphonolipid analog of dipalmitoyl phosphatidylcholine (DPPC, the major zwitterionic phospholipid in native lung surfactant). Activity experiments measured both adsorption and dynamic surface tension lowering due to the known importance of these surface behaviors in lung surfactant function in vivo. Synthetic surfactants containing 9 : 1 DEPN-8:PG 1 + 3% S-MB were resistant to degradation by PLA2 in chromatographic studies, while calf lung surfactant extract (CLSE, the substance of the bovine clinical surfactant Infasurf®) was significantly degraded by PLA2. The 9 : 1 DEPN-8:PG 1 + 3% S-MB mixture also had small but consistent increases in both adsorption and dynamic surface tension lowering ability compared to DEPN-8 + 3% S-MB. Consistent with these surface activity increases, molecular dynamics simulations using Protein Modeller, GROMACS force-field, and PyMOL showed that bilayers containing DPPC and palmitoyl-oleoyl-PC (POPC) as surrogates of DEPN-8 and PG 1 were penetrated to a greater extent by S-MB peptide than bilayers of DPPC alone. These results suggest that PG 1 or related anionic phosphono-PG analogs may have functional utility in phospholipase-resistant synthetic surfactants targeting forms of acute pulmonary injury where endogenous surfactant becomes dysfunctional due to phospholipase activity in the innate inflammatory response. PMID:22530092
Phosphoglycerate Mutase 1 Coordinates Glycolysis and Biosynthesis to Promote Tumor Growth
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hitosugi, Taro; Zhou, Lu; Elf, Shannon
2012-11-12
It is unclear how cancer cells coordinate glycolysis and biosynthesis to support rapidly growing tumors. We found that the glycolytic enzyme phosphoglycerate mutase 1 (PGAM1), commonly upregulated in human cancers due to loss of TP53, contributes to biosynthesis regulation partially by controlling intracellular levels of its substrate, 3-phosphoglycerate (3-PG), and product, 2-phosphoglycerate (2-PG). 3-PG binds to and inhibits 6-phosphogluconate dehydrogenase in the oxidative pentose phosphate pathway (PPP), while 2-PG activates 3-phosphoglycerate dehydrogenase to provide feedback control of 3-PG levels. Inhibition of PGAM1 by shRNA or a small molecule inhibitor PGMI-004A results in increased 3-PG and decreased 2-PG levels in cancermore » cells, leading to significantly decreased glycolysis, PPP flux and biosynthesis, as well as attenuated cell proliferation and tumor growth.« less
Serum interleukin-6 levels in murine models of Candida albicans infection.
Kovács, Renátó; Czudar, Anita; Horváth, László; Szakács, Levente; Majoros, László; Kónya, József
2014-03-01
Two Balb/C mouse models of Candida infection were used to detect serum interleukin-6 (IL-6) responses. The first model used systemic infection by Candida albicans ATCC 10231 strain infected through the lateral tail vein of mice without any specific pretreatment. The median Candida burdens of the kidneys were 1.5 × 106 CFU/ml 24 h postinoculation (p.i.) and 1.2 × 107 CFU/ml 72 h p.i., while median serum IL-6 levels were 479.3 pg/ml and 934.5 pg/ml, respectively. The Candida burden showed significant correlation with serum IL-6 24 h p.i. (R2 = 0.6358; P = 0.0082) but not 72 h p.i.The second model was a mouse vaginitis model applying intravaginal inoculation of mice pretreated with subcutaneous estradiol-valerate (10 mg/ml) 3 days before infection. Candida cell count in vaginal lavage fluid was 2.8 × 106 CFU/ml 24 h p.i. and 1.4 × 108 CFU/ml 72 h p.i. Serum IL-6 response was detected in 4 of 15 mice 24 h p.i. and 9 of 15 mice 72 h p.i. Even the responders had low IL-6 serum levels (mean values 29.9 pg/ml and 60.1 pg/ml, respectively) not correlating with Candida cell count in vaginal lavage fluid.In conclusion, serum IL-6 had strong relationship with systemic C. albicans infection while the local C. albicans infection of the vagina led to partial, prolonged and limited serum IL-6 response.
Tokumura, Masahiro; Miyake, Yuichi; Wang, Qi; Nakayama, Hayato; Amagai, Takashi; Ogo, Sayaka; Kume, Kazunari; Kobayashi, Takeshi; Takasu, Shinji; Ogawa, Kumiko
2018-04-16
Organophosphorus flame retardants (PFRs) are extensively used as alternatives to banned polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). In this study, we analyzed 14 PFRs by means of four mass-spectrometry-based methods: gas chromatography combined with electron-impact mass spectrometry (GC-EI-MS) or negative-chemical-ionization mass spectrometry (GC-NCI-MS) and liquid chromatography combined with tandem mass spectrometry using electrospray ionization (LC-ESI-MS/MS) or atmospheric pressure chemical ionization (LC-APCI-MS/MS). The limits of quantification (LOQs) for LC-ESI-MS/MS and LC-APCI-MS/MS (0.81-970 pg) were 1-2 orders of magnitude lower than the LOQs for GC-EI-MS and GC-NCI-MS (2.3-3900 pg). LC-APCI-MS/MS showed the lowest LOQs (mean = 41 pg; median = 3.4 pg) for all but two of the PFRs targeted in this study. For LC-APCI-MS/MS, the lowest LOQ was observed for tributyl phosphate (TBP) (0.81 pg), and the highest was observed for tris(butoxyethyl) phosphate (TBOEP) (36 pg). The results of this study indicate that LC-APCI-MS/MS is the optimum analytical method for the target PFRs, at least in terms of LOQ.
The Effects of Panax ginseng and Panax quinquefolius on Thermoregulation in Animal Models
Hong, Bin Na; Do, Moon Ho; Her, You Ri
2015-01-01
We devised a study using animal models of hyperthermia and hypothermia and also attempted to accurately assess the effects of Panax ginseng (PG) and Panax quinquefolius (PQ) on body temperature using these models. In addition, we investigated the effects of PG and PQ in our animal models in high and low temperature environments. The results of our experiments show that mice with normothermia, hyperthermia, and hypothermia maintained their body temperatures after a certain period in accordance with the condition of each animal model. In our experiments of body temperature change in models of normal, low, or high room temperature, the hyperthermic model did not show any body temperature change in either the PG- or PQ-administered group. In the normal and low room temperature models, the group administered PG maintained body temperature, while the body temperature of the PQ-administered group was lower than or similar to that of the control group. In conclusion, the fact that PG increases body temperature could not be verified until now. We also showed that the effect of maintaining body temperature in the PG-administered group was superior in a hypothermia-prone low temperature environment. PMID:25709709
Fu, Jilagamazhi; Sharma, Umesh; Sparling, Richard; Cicek, Nazim; Levin, David B
2014-07-01
Medium-chain-length polyhydroxyalkanoate (mcl-PHA) production by Pseudomonas putida LS46 was analyzed in shake-flask-based batch reactions, using pure chemical-grade glycerol (PG), biodiesel-derived "waste" glycerol (WG), and biodiesel-derived "waste" free fatty acids (WFA). Cell growth, substrate consumption, mcl-PHA accumulation within the cells, and the monomer composition of the synthesized biopolymers were monitored. The patterns of mcl-PHA synthesis in P. putida LS46 cells grown on PG and WG were similar but differed from that of cells grown with WFA. Polymer accumulation in glycerol-based cultures was stimulated by nitrogen limitation and plateaued after 48 h in both PG and WG cultures, with a total accumulation of 17.9% cell dry mass and 16.3% cell dry mass, respectively. In contrast, mcl-PHA synthesis was independent of nitrogen concentration in P. putida LS46 cells cultured with WFA, which accumulated to 29% cell dry mass. In all cases, the mcl-PHAs synthesized consisted primarily of 3-hydroxyoctanoate (C(8)) and 3-hydroxydecanoate (C(10)). WG and WFA supported similar or greater cell growth and mcl-PHA accumulation than PG under the experimental conditions used. These results suggest that biodiesel by-product streams could be used as low-cost carbon sources for sustainable mcl-PHA production.
Stimulation by unsaturated fatty acid of squalene uptake in rat liver microsomes.
Chin, J; Bloch, K
1985-07-01
Supernatant protein factor (SPF) and anionic phospholipids such as phosphatidylglycerol (PG) stimulate squalene epoxidase activity in rat liver microsomes by promoting [3H]squalene uptake as well as substrate translocation (Chin, J., and K. Bloch. 1984. J. Biol. Chem. 259: 11735-11738). This process is postulated to be membrane-mediated and not carrier-mediated. Here we show that treatment of PG with phospholipase A2 in the presence of bovine serum albumin abolishes the stimulatory effect of SPF on epoxidase activity. Disaturated fatty acyl-PGs are not as effective as egg yolk lecithin PG in the SPF effect. These findings suggest an important role for the unsaturated fatty acid moiety of PG. We also show that at submicellar concentrations, cis-unsaturated fatty acids stimulate microsomal epoxidase activity whereas saturated fatty acids do not. This effect is due to an increase in substrate uptake which in turn may facilitate substrate availability to the enzyme.
NASA Astrophysics Data System (ADS)
Hourigan, Breanne
Glioblastoma multiforme (GBM), a grade IV glioma, is the most common primary brain tumor, affecting about 3 out of 100,000 persons per year in the United States. GBM accounts for about 80% of primary malignant brain tumors, and is also the most aggressive of malignant brain tumors. With exhaustive treatment, survival only averages between 12 and 15 months, with a 2-year survival rate less than 25%. New therapeutic strategies are necessary to improve the outcomes of this disease. Chemotherapy with temozolomide (TMZ), a DNA alkylating agent, is used as a first-line of treatment for GBM. However, GBM tumors develop resistance to TMZ over time due to increased expression of O6-methylguanine-DNA methyltransferase (MGMT), a gene responsible for DNA repair. We previously developed cationic, amphiphilic copolymer poly(lactide-co-glycolide)-g-polyethylenimine (PgP) and demonstrated its utility for nucleic acid delivery. Here, we examine the ability of PgP polyplexes to overcome TMZ resistance and improve therapeutic efficacy through combination drug and gene therapy for GBM treatment. In this study, we evaluated the ability of PgP to deliver siRNA targeting to MGMT (siMGMT), a gene responsible for drug resistance in GBM. Our results demonstrated that PgP effectively forms stable complex with siRNA and protects siRNAs from heparin competition assay, serum- and ribonuclease-mediated degradation, confirming the potential of the polyplex for in vivo delivery. Results from MTT assays showed that PgP/siRNA polyplexes exhibited minimal cytotoxicity compared to untreated cells when incubated with T98G human GBM cells. We also demonstrated that PgP/siMGMT polyplexes mediate knockdown of MGMT protein as well as a significant ˜56% and ˜68% knockdown of MGMT mRNA in T98G GBM cells compared to cells treated with PgP complexed with non-targeting siRNA (siNT) at a 60:1 and 80:1 nitrogen:phosphate (N:P) ratio, respectively. Further, co-incubation of PgP/siMGMT polyplexes with TMZ enhanced therapeutic efficacy in T98G GBM cells compared to treatment with the polyplex or TMZ alone. After generation of athymic mouse GBM model, PgP/siMGMT polyplexes were locally injected into the tumor. Relative to untreated injury only, PgP/siMGMT polyplexes significantly reduced MGMT mRNA and protein expression at 3 days post-injection. These studies demonstrate that PgP is an efficient non-viral delivery carrier for therapeutic siMGMT to the tumor cells and may be a promising platform for the combinatorial siRNA/drug therapy for GBM treatment. In the future, we will study the therapeutic efficacy of combination of PgP/siMGMT and TMZ in athymic mouse GBM model.
The Distributed Nature of Pattern Generalization
ERIC Educational Resources Information Center
Rivera, Ferdinand
2015-01-01
Drawing on a review of recent work conducted in the area of pattern generalization (PG), this paper makes a case for a distributed view of PG, which basically situates processing ability in terms of convergences among several different factors that influence PG. Consequently, the distributed nature leads to different types of PG that depend on the…
Mikecz, Katalin; Glant, Tibor T.; Markovics, Adrienn; Rosenthal, Kenneth S.; Kurko, Julia; Carambula, Roy E.; Cress, Steve; Steiner, Harold L.; Zimmerman, Daniel H.
2017-01-01
Rheumatoid arthritis (RA) is an autoimmune joint disease maintained by aberrant immune responses involving CD4+ T helper (Th)1 and Th17 cells. In this study, we tested the therapeutic efficacy of Ligand Epitope Antigen Presentation System (LEAPS™) vaccines in two Th1 cell-driven mouse models of RA, cartilage proteoglycan (PG)-induced arthritis (PGIA) and PG G1-domain-induced arthritis (GIA). The immunodominant PG peptide PG70 was attached to a DerG or J immune cell binding peptide, and the DerG-PG70 and J-PG70 LEAPS vaccines were administered to the mice after the onset of PGIA or GIA symptoms. As indicated by significant decreases in visual and histopathological scores of arthritis, the DerG-PG70 vaccine inhibited disease progression in both PGIA and GIA, while the J-PG70 vaccine was ineffective. Splenic CD4+ cells from DerG-PG70-treated mice were diminished in Th1 and Th17 populations but enriched in Th2 and regulatory T (Treg) cells. In vitro spleen cell-secreted and serum cytokines from DerG-PG70-treated mice demonstrated a shift from a pro-inflammatory to an anti-inflammatory/regulatory profile. DerG-PG70 peptide tetramers preferentially bound to CD4+ T-cells of GIA spleen cells. We conclude that the DerG-PG70 vaccine (now designated CEL-4000) exerts its therapeutic effect by interacting with CD4+ cells, which results in an antigen-specific down-modulation of pathogenic T-cell responses in both the PGIA and GIA models of RA. Future studies will need to determine the potential of LEAPS vaccination to provide disease suppression in patients with RA. PMID:28583308
Quantitative characterization of prostaglandins in the uterus of early pregnant cattle.
Ulbrich, S E; Schulke, K; Groebner, A E; Reichenbach, H D; Angioni, C; Geisslinger, G; Meyer, H H D
2009-08-01
Prostaglandins (PGs) are important regulators of reproductive processes including early embryonic development. We analyzed the most relevant PG in bovine uteri at different preimplantation pregnancy stages when compared with non-pregnant controls. Additionally, endometrium and trophoblast tissues were examined regarding specific enzymes and receptors involved in PG generation and function. Simmental heifers were artificially inseminated or received seminal plasma only. At days 12, 15, or 18, post-estrus uteri were flushed for PG determination by liquid chromatography-tandem mass spectrometry. Endometrium and trophoblast tissues were sampled for RNA extraction and quantitative real-time PCR analysis. At all days and points of time examined, the concentration of 6-keto PGF(1alpha) (stable metabolite of PGI(2)) was predominant followed by PGF(2alpha)>PGE(2)>PGD(2) approximately TXB(2) (stable metabolite of TXA(2)). At days 15 and 18, PG increased from overall low levels at day 12, with a much more pronounced increase during pregnancy. The PGF(2alpha)/PGE(2) ratio was not influenced by status. The highest PG concentration was measured at day 15 with 6-keto PGF(1alpha) (6.4 ng/ml) followed by PGF(2alpha) (1.1 ng/ml) and PGE(2) (0.3 ng/ml). Minor changes in endometrial PG biosynthesis enzymes occurred due to pregnancy. Trophoblasts revealed high transcript abundance of general and specific PG synthases contributing to uterine PG. As PGI(2) and PGF(2alpha) receptors were abundantly expressed by the trophoblast, abundant amounts of PGI(2) and PGF(2alpha) in the uterine lumen point towards an essential role of PG for the developing embryo. High amounts of PG other than PGE(2) in the preimplantation uterus may be essential rather than detrimental for successful reproduction.
Wang, Mengjing; Liu, Wenbin; Hou, Meifang; Li, Qianqian; Han, Ying; Liu, Guorui; Li, Haifeng; Liao, Xiao; Chen, Xuebin; Zheng, Minghui
2016-01-01
The sintering flue gas samples were collected at the inlets and outlets of the desulfurization systems to evaluate the influence of the systems on PCNs emission concentrations, profiles, and emission factors. The PCNs concentrations at the inlets and outlets were 27888–153672 pg m−3 and 11988–42245 pg m−3,respectively. Desulfurization systems showed excellent removal for PCNs, and the removal efficiencies of PCNs increase with increasing chlorination level. Lower chlorinated homologs are more sensitive to the desulfurization process than higher ones. High levels of PCNs were also detected in the gypsum (11600–29720 pg g−1) and fly ash samples (4946–64172 pg g−1). The annual total emissions of PCNs released to flue gas and gypsum from the sintering plants were about 394 kg, 48.5% of which was in gypsum. The surface area of the fly ash samples increased significantly from the first to the fourth stage of the series-connected electrostatic precipitator, accompanying obvious rising of concentration of PCNs in the fly ash samples. PMID:27197591
Controlled carrier screening in p-n NiO/GaN piezoelectric generators by an Al2O3 insertion layer
NASA Astrophysics Data System (ADS)
Johar, Muhammad Ali; Jeong, Dae Kyung; Afifi Hassan, Mostafa; Kang, Jin-Ho; Ha, Jun-Seok; Key Lee, June; Ryu, Sang-Wan
2017-12-01
The performance of a piezoelectric generator (PG) depends significantly on the internal screening process inside the device. As piezoelectric charges appear on both ends of the piezoelectric crystal, internal screening starts to decrease the piezoelectric bias. Therefore, the piezoelectric energy generated by external stress is not fully utilized by external circuit, which is the most challenging aspect of high-efficiency PGs. In this work, the internal screening effect of a NiO/GaN p-n PG was analyzed and controlled with an Al2O3 insertion layer. Internal screening in the p-n diode PG was categorized into free-carrier screening in neutral regions and junction screening due to charge drift across the junction. It was observed that junction screening could be significantly suppressed by inserting an Al2O3 layer and that effect was dominant in a leaky diode PG. With this implementation, the piezoelectric bias of the NiO/GaN PG was improved by a factor of ~100 for high-leakage diodes and a factor of ~1.6 for low-leakage diodes. Consequently, NiO/Al2O3/GaN PGs under a stress of 5 MPa provided a piezoelectric bias of 12.1 V and a current density of 2.25 µA cm-2. The incorporation of a highly resistive Al2O3 layer between p-NiO and n-GaN layers in NiO/GaN heterojunctions provides an efficient means of improving the piezoelectric performance by controlling the internal screening of the piezoelectric field.
pgRNAFinder: a web-based tool to design distance independent paired-gRNA.
Xiong, Yuanyan; Xie, Xiaowei; Wang, Yanzhi; Ma, Wenbing; Liang, Puping; Songyang, Zhou; Dai, Zhiming
2017-11-15
The CRISPR/Cas System has been shown to be an efficient and accurate genome-editing technique. There exist a number of tools to design the guide RNA sequences and predict potential off-target sites. However, most of the existing computational tools on gRNA design are restricted to small deletions. To address this issue, we present pgRNAFinder, with an easy-to-use web interface, which enables researchers to design single or distance-free paired-gRNA sequences. The web interface of pgRNAFinder contains both gRNA search and scoring system. After users input query sequences, it searches gRNA by 3' protospacer-adjacent motif (PAM), and possible off-targets, and scores the conservation of the deleted sequences rapidly. Filters can be applied to identify high-quality CRISPR sites. PgRNAFinder offers gRNA design functionality for 8 vertebrate genomes. Furthermore, to keep pgRNAFinder open, extensible to any organism, we provide the source package for local use. The pgRNAFinder is freely available at http://songyanglab.sysu.edu.cn/wangwebs/pgRNAFinder/, and the source code and user manual can be obtained from https://github.com/xiexiaowei/pgRNAFinder. songyang@bcm.edu or daizhim@mail.sysu.edu.cn. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.
An unbiased risk estimator for image denoising in the presence of mixed poisson-gaussian noise.
Le Montagner, Yoann; Angelini, Elsa D; Olivo-Marin, Jean-Christophe
2014-03-01
The behavior and performance of denoising algorithms are governed by one or several parameters, whose optimal settings depend on the content of the processed image and the characteristics of the noise, and are generally designed to minimize the mean squared error (MSE) between the denoised image returned by the algorithm and a virtual ground truth. In this paper, we introduce a new Poisson-Gaussian unbiased risk estimator (PG-URE) of the MSE applicable to a mixed Poisson-Gaussian noise model that unifies the widely used Gaussian and Poisson noise models in fluorescence bioimaging applications. We propose a stochastic methodology to evaluate this estimator in the case when little is known about the internal machinery of the considered denoising algorithm, and we analyze both theoretically and empirically the characteristics of the PG-URE estimator. Finally, we evaluate the PG-URE-driven parametrization for three standard denoising algorithms, with and without variance stabilizing transforms, and different characteristics of the Poisson-Gaussian noise mixture.
Nandel, Fateh S; Shafique, Mohd
2014-10-01
The non-proteinogenic amino acids--phenylglycine (PG) and hydroxyphenylglycine (HPG) are crucial components of certain peptidic natural products and are important for the preparation of various medicines. In this, study, the conformation of model dipeptides Ac-X-NHMe of PG, p-HPG and 3, 5-di-hydroxyphenylglycine (3, 5-DHPG) was studied both in R and S form by quantum mechanical (QM) and molecular dynamics approaches. On the energy scale, the conformational states of these molecules in both the R and S were found to be degenerate by QM studies, stabilized by non-covalent interactions like carbonyl--carbonyl interactions, carbonyl-lp .. π (aromatic ring) interactions etc. These interactions disappeared/weakened due to interaction of water molecules with carbonyl groups of backbone in simulation and water was found to interact with the aromatic ring through O(w)-H .. π or O(w)lp .. π interactions. The degeneracy of conformational states was lifted in favor of R-form of PG and DHPG and water molecules interactions with aromatic ring led to non-planarity of the aromatic ring. In simulation studies, irrespective of the starting geometry, the Φ, ψ values for the R form correspond to inverse β/inverse collagen region and for the S-form, the Φ, ψ values correspond to β/collagen region i.e., adopt single conformation. The obtained results were in conformity with the CD spectroscopic data on D-PG and D-p-HPG. The conformational behavior of the unusual amino acids might be of great help in designing of bioactive peptides/peptide based drugs to be realized in single conformation--an essential requirement.
Park, Min Cheol; Kim, Moojong; Lim, Gun Taek; Kang, Sung Min; An, Seong Soo A; Kim, Tae Song; Kang, Ji Yoon
2016-06-21
Multiwell plates are regularly used in analytical research and clinical diagnosis but often require laborious washing steps and large sample or reagent volumes (typically, 100 μL per well). To overcome such drawbacks in the conventional multiwell plate, we present a novel microchannel-connected multiwell plate (μCHAMP) that can be used for automated disease biomarker detection in a small sample volume by performing droplet-based magnetic bead immunoassay inside the plate. In this μCHAMP-based immunoassay platform, small volumes (30-50 μL) of aqueous-phase working droplets are stably confined within each well by the simple microchannel structure (200-300 μm in height and 0.5-1 mm in width), and magnetic beads are exclusively transported into an adjacent droplet through the oil-filled microchannels assisted by a magnet array aligned beneath and controlled by a XY-motorized stage. Using this μCHAMP-based platform, we were able to perform parallel detection of synthetic amyloid beta (Aβ) oligomers as a model analyte for the early diagnosis of Alzheimer's disease (AD). This platform easily simplified the laborious and consumptive immunoassay procedure by achieving automated parallel immunoassay (32 assays per operation in 3-well connected 96-well plate) within 1 hour and at low sample consumption (less than 10 μL per assay) with no cumbersome manual washing step. Moreover, it could detect synthetic Aβ oligomers even below 10 pg mL(-1) concentration with a calculated detection limit of ∼3 pg mL(-1). Therefore, the μCHAMP and droplet-based magnetic bead immunoassay, with the combination of XY-motorized magnet array, would be a useful platform in the diagnosis of human disease, including AD, which requires low consumption of the patient's body fluid sample and automation of the entire immunoassay procedure for high processing capacity.
NASA Astrophysics Data System (ADS)
Song, Xiaoling; Zhang, Yue; Wei, Song; Huang, Jie
2013-03-01
The effects of different hydrolysis methods on peptidoglycan (PG) were assessed in terms of their impact on the innate immunity and disease resistance of Pacific white shrimp, Litop enaeus vannamei. PG derived from Bifidobacterium thermophilum was prepared in the laboratory and processed with lysozyme and protease under varying conditions to produce several different PG preparations. A standard shrimp feed was mixed with 0.05% PG preparations to produce a number of experimental diets for shrimp. The composition, concentration, and molecular weight ranges of the soluble PG were analyzed. Serum phenoloxidase and acid phosphatase activity in the shrimp were determined on Days 6—31 of the experiment. The protective activity of the PG preparations was evaluated by exposing shrimp to white spot syndrome virus (WSSV). Data on the composition of the PG preparations indicated that preparations hydrolyzed with lysozyme for 72 h had more low-molecular-weight PG than those treated for 24 h, and hydrolysis by protease enhanced efficiency of hydrolysis compared to lysozyme. SDS-PAGE showed changes in the molecular weight of the soluble PG produced by the different hydrolysis methods. Measurements of serum phenoloxidase and acid phosphatase activity levels in the shrimp indicated that the PG preparations processed with enzymes were superior to the preparation which had not undergone hydrolysis in enhancing the activity of the two serum enzymes. In addition, the preparation containing more low-molecular-weight PG enhanced the resistance of the shrimp to WSSV, whereas no increased resistance was observed for preparations containing less low-molecular-weight PG. These findings suggest that the immunity-enhancing activity of PG is related to its molecular weight and that increasing the quantity of low-molecular-weight PG can fortify the effect of immunity enhancement.
Sayarlioglu, Hayriye; Topal, Cevat; Sayarlioglu, Mehmet; Dulger, Haluk; Dogan, Ekrem; Erkoc, Reha
2004-01-01
OBJECTIVE: It is known that glucose concentrations of peritoneal dialysis solutions are detrimental to the peritoneal membrane. In order to determine the effect of glucose concentration on cytokine levels of peritoneal fluid of continuous ambulatory peritoneal dialysis (CAPD) patients, a cross-sectional study was performed. METHODS: Nine non-diabetic CAPD patients participated in two 8-h dwell sessions of overnight exchanges in consecutive days, with 1.36% and 3.86% glucose containing peritoneal dialysis solutions (Baxter-Eczacibas). Peritoneal dialysis fluid tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 levels were measured. RESULTS: TNF-alpha levels after 1.36% and 3.86% glucose used dwells were 23+/-14 pg/ml and 28+/-4 pg/ml, respectively (p=0.78). The IL-6 levels were 106+/-57 pg/ml and 115+/-63 pg/ml (p=0.81), respectively. CONCLUSION: In our in vivo study we found that the glucose concentration of the conventional lactate-based CAPD solution has no effect on basal IL-6 and TNF-alpha levels of peritoneal fluid. Further in vivo studies with non-lactate-based CAPD solutions are needed in order to determine the effect of glucose concentration per se on cytokine release. PMID:15203553
Stronks, Dirk L.; Dik, Willem A.; Schreurs, Marco W. J.
2017-01-01
The immune system has long been thought to be involved in the pathophysiology of complex regional pain syndrome (CRPS). However, not much is known about the role of the immune system and specifically T-cells in the onset and maintenance of this disease. In this study, we aimed to evaluate T-cell activity in CRPS by comparing blood soluble interleukin-2 receptor (sIL-2R) levels between CRPS patients and healthy controls. CRPS patients had statistically significant elevated levels of sIL-2R as compared to healthy controls (median sIL-2R levels: 4151 pg/ml (Q3 − Q1 = 5731 pg/ml − 3546 pg/ml) versus 1907 pg/ml (Q3 − Q1: 2206 pg/ml − 1374 pg/ml), p < 0.001, resp.). Furthermore, sIL-2R level seems to be a good discriminator between CRPS patients and healthy controls with a high sensitivity (90%) and specificity (89.5%). Our finding indicates increased T-cell activity in patients with CRPS. This finding is of considerable relevance as it could point towards a T-cell-mediated inflammatory process in this disease. This could pave the way for new anti-inflammatory therapies in the treatment of CRPS. Furthermore, sIL-2R could be a promising new marker for determining inflammatory disease activity in CRPS. PMID:28634419
Zhuang, Qianlai; Zhu, Xudong; He, Yujie; Prigent, Catherine; Melillo, Jerry M.; McGuire, A. David; Prinn, Ronald G.; Kicklighter, David W.
2015-01-01
Estimates of the seasonal and interannual exchanges of carbon dioxide (CO2) and methane (CH4) between land ecosystems north of 45°N and the atmosphere are poorly constrained, in part, because of uncertainty in the temporal variability of water-inundated land area. Here we apply a process-based biogeochemistry model to evaluate how interannual changes in wetland inundation extent might have influenced the overall carbon dynamics of the region during the time period 1993–2004. We find that consideration by our model of these interannual variations between 1993 and 2004, on average, results in regional estimates of net methane sources of 67.8 ± 6.2 Tg CH4 yr−1, which is intermediate to model estimates that use two static inundation extent datasets (51.3 ± 2.6 and 73.0 ± 3.6 Tg CH4 yr−1). In contrast, consideration of interannual changes of wetland inundation extent result in regional estimates of the net CO2 sink of −1.28 ± 0.03 Pg C yr−1 with a persistent wetland carbon sink from −0.38 to −0.41 Pg C yr−1 and a upland sink from −0.82 to −0.98 Pg C yr−1. Taken together, despite the large methane emissions from wetlands, the region is a consistent greenhouse gas sink per global warming potential (GWP) calculations irrespective of the type of wetland datasets being used. However, the use of satellite-detected wetland inundation extent estimates a smaller regional GWP sink than that estimated using static wetland datasets. Our sensitivity analysis indicates that if wetland inundation extent increases or decreases by 10% in each wetland grid cell, the regional source of methane increases 13% or decreases 12%, respectively. In contrast, the regional CO2 sink responds with only 7–9% changes to the changes in wetland inundation extent. Seasonally, the inundated area changes result in higher summer CH4 emissions, but lower summer CO2 sinks, leading to lower summer negative greenhouse gas forcing. Our analysis further indicates that wetlands play a disproportionally important role in affecting regional greenhouse gas budgets given that they only occupy approximately 10% of the total land area in the region.
Li, H; Ji, H; Wu, S S; Hou, B X
2016-12-09
Objective: To analyze the protein expression profile and the potential virulence factors of Porphyromonas endodontalis (Pe) via comparison with that of two strains of Porphyromonas gingivalis (Pg) with high and low virulences, respectively. Methods: Whole cell comparative proteomics of Pe ATCC35406 was examined and compared with that of high virulent strain Pg W83 andlow virulent strain Pg ATCC33277, respectively. Isobaric tags for relative and absolute quantitation (iTRAQ) combined with nano liquid chromatography-tandem mass spectrometry (Nano-LC-MS/MS) were adopted to identify and quantitate the proteins of Pe and two strains of Pg with various virulences by using the methods of isotopically labeled peptides, mass spectrometric detection and bioinformatics analysis. The biological functions of similar proteins expressed by Pe ATCC35406 and two strains of Pg were quantified and analyzed. Results: Totally 1 210 proteins were identified while Pe compared with Pg W83. There were 130 proteins (10.74% of the total proteins) expressed similarly, including 89 known functional proteins and 41 proteins of unknown functions. Totally 1 223 proteins were identified when Pe compared with Pg ATCC33277. There were 110 proteins (8.99% of the total proteins) expressed similarly, including 72 known functional proteins and 38 proteins of unknown functions. The similarly expressed proteins in Pe and Pg strains with various virulences mainly focused on catalytic activity and binding function, including recombination activation gene (RagA), lipoprotein, chaperonin Dnak, Clp family proteins (ClpC and ClpX) and various iron-binding proteins. They were involved in metabolism and cellular processes. In addition, the type and number of similar virulence proteins between Pe and high virulence Pg were higher than those between Pe and low virulence Pg. Conclusions: Lipoprotein, oxygen resistance protein, iron binding protein were probably the potential virulence factors of Pe ATCC35406. It was speculated that pathogenicity of Pe was more similar to high virulence Pg than that to low virulence strain.
Lee, C C; Lin, W T; Liao, P C; Su, H J; Chen, H L
2006-05-01
An abandoned pentachlorophenol plant and nearby area in southern Taiwan was heavily contaminated by dioxins, impurities formed in the PCP production process. The investigation showed that the average serum PCDD/Fs of residents living nearby area (62.5 pg WHO-TEQ/g lipid) was higher than those living in the non-polluted area (22.5 and 18.2 pg WHO-TEQ/g lipid) (P<0.05). In biota samples, average PCDD/F of milkfish in sea reservoir (28.3 pg WHO-TEQ/g) was higher than those in the nearby fish farm (0.15 pg WHO-TEQ/g), and Tilapia and shrimp showed the similar trend. The average daily PCDD/Fs intake of 38% participants was higher than 4 pg WHO-TEQ/kg/day suggested by the world health organization. Serum PCDD/F was positively associated with average daily intake (ADI) after adjustment for age, sex, BMI, and smoking status. In addition, a prospective cohort study is suggested to determine the long-term health effects on the people living near factory.
NASA Astrophysics Data System (ADS)
Norton, Alexander J.; Rayner, Peter J.; Koffi, Ernest N.; Scholze, Marko
2018-04-01
The synthesis of model and observational information using data assimilation can improve our understanding of the terrestrial carbon cycle, a key component of the Earth's climate-carbon system. Here we provide a data assimilation framework for combining observations of solar-induced chlorophyll fluorescence (SIF) and a process-based model to improve estimates of terrestrial carbon uptake or gross primary production (GPP). We then quantify and assess the constraint SIF provides on the uncertainty in global GPP through model process parameters in an error propagation study. By incorporating 1 year of SIF observations from the GOSAT satellite, we find that the parametric uncertainty in global annual GPP is reduced by 73 % from ±19.0 to ±5.2 Pg C yr-1. This improvement is achieved through strong constraint of leaf growth processes and weak to moderate constraint of physiological parameters. We also find that the inclusion of uncertainty in shortwave down-radiation forcing has a net-zero effect on uncertainty in GPP when incorporated into the SIF assimilation framework. This study demonstrates the powerful capacity of SIF to reduce uncertainties in process-based model estimates of GPP and the potential for improving our predictive capability of this uncertain carbon flux.
PG4KDS: A Model for the Clinical Implementation of Pre-emptive Pharmacogenetics
Hoffman, James M.; Haidar, Cyrine E.; Wilkinson, Mark R.; Crews, Kristine R.; Baker, Donald K.; Kornegay, Nancy M.; Yang, Wenjian; Pui, Ching-Hon; Reiss, Ulrike M.; Gaur, Aditya H.; Howard, Scott C.; Evans, William E.; Broeckel, Ulrich; Relling, Mary V.
2014-01-01
Pharmacogenetics is frequently cited as an area for initial focus of the clinical implementation of genomics. Through the PG4KDS protocol, St. Jude Children’s Research Hospital pre-emptively genotypes patients for 230 genes using the Affymetrix Drug Metabolizing Enzymes and Transporters (DMET) Plus array supplemented with a CYP2D6 copy number assay. The PG4KDS protocol provides a rational, stepwise process for implementing gene/drug pairs, organizing data, and obtaining consent from patients and families. Through August 2013, 1559 patients have been enrolled, and 4 gene tests have been released into the electronic health record (EHR) for clinical implementation: TPMT, CYP2D6, SLCO1B1, and CYP2C19. These genes are coupled to 12 high-risk drugs. Of the 1016 patients with genotype test results available, 78% of them had at least one high-risk (i.e., actionable) genotype result placed in their EHR. Each diplotype result released to the EHR is coupled with an interpretive consult that is created in a concise, standardized format. To support-gene based prescribing at the point of care, 55 interruptive clinical decision support (CDS) alerts were developed. Patients are informed of their genotyping result and its relevance to their medication use through a letter. Key elements necessary for our successful implementation have included strong institutional support, a knowledgeable clinical laboratory, a process to manage any incidental findings, a strategy to educate clinicians and patients, a process to return results, and extensive use of informatics, especially CDS. Our approach to pre-emptive clinical pharmacogenetics has proven feasible, clinically useful, and scalable. PMID:24619595
PG4KDS: a model for the clinical implementation of pre-emptive pharmacogenetics.
Hoffman, James M; Haidar, Cyrine E; Wilkinson, Mark R; Crews, Kristine R; Baker, Donald K; Kornegay, Nancy M; Yang, Wenjian; Pui, Ching-Hon; Reiss, Ulrike M; Gaur, Aditya H; Howard, Scott C; Evans, William E; Broeckel, Ulrich; Relling, Mary V
2014-03-01
Pharmacogenetics is frequently cited as an area for initial focus of the clinical implementation of genomics. Through the PG4KDS protocol, St. Jude Children's Research Hospital pre-emptively genotypes patients for 230 genes using the Affymetrix Drug Metabolizing Enzymes and Transporters (DMET) Plus array supplemented with a CYP2D6 copy number assay. The PG4KDS protocol provides a rational, stepwise process for implementing gene/drug pairs, organizing data, and obtaining consent from patients and families. Through August 2013, 1,559 patients have been enrolled, and four gene tests have been released into the electronic health record (EHR) for clinical implementation: TPMT, CYP2D6, SLCO1B1, and CYP2C19. These genes are coupled to 12 high-risk drugs. Of the 1,016 patients with genotype test results available, 78% of them had at least one high-risk (i.e., actionable) genotype result placed in their EHR. Each diplotype result released to the EHR is coupled with an interpretive consult that is created in a concise, standardized format. To support-gene based prescribing at the point of care, 55 interruptive clinical decision support (CDS) alerts were developed. Patients are informed of their genotyping result and its relevance to their medication use through a letter. Key elements necessary for our successful implementation have included strong institutional support, a knowledgeable clinical laboratory, a process to manage any incidental findings, a strategy to educate clinicians and patients, a process to return results, and extensive use of informatics, especially CDS. Our approach to pre-emptive clinical pharmacogenetics has proven feasible, clinically useful, and scalable. © 2014 Wiley Periodicals, Inc.
Serrat, Manuel; Bermúdez, Rose Catalina; Villa, Tomás Gonzáles
2002-03-01
A new high polygalacturonase (PG)-producing Kluyveromyces marxianus strain was isolated from coffee wet-processing wastewater. PG production in this strain is not repressed in the presence of 100 g/L of glucose and, being growth-associated, reached its maximum accumulation in the culture medium at the beginning of the stationary phase. Oxygen and galacturonic acid negatively regulated enzyme synthesis, and glucose as the carbon source afforded better enzyme yields than lactose. The data reported here show that this strain exhibits the highest index of PG production among the wild-type strains reported so far (18.8 U/mL). PG was readily purified by ion-exchange chromatography on SP-Sepharose FF. The activity corresponded to a single protein with an M(r) of 41.7kDa according to sodium dodecyl sulfatepolyacrylamide gel electrophoresis. The enzyme was stable in the pH range of 3.0-5.0 and displayed an optimal temperature of 55 degrees C; it showed a typical endosplitting way of substrate hydrolysis and exhibited a fair degree of activity on pectin with a high degree of esterification.
The polygalacturonase FaPG1 gene plays a key role in strawberry fruit softening
García-Gago, Juan A; Posé, Sara; Muñoz-Blanco, Juan; Quesada, Miguel A
2009-01-01
The loss of firm texture is one of the most characteristic physiological processes that occur during the ripening of fleshy fruits. It is generally accepted that the disassembly of primary cell wall and middle lamella is the main factor involved in fruit softening. In this process, polygalacturonase (PG) has been implicated in the degradation of the polyuronide network in several fruits. However, the minor effect of PG downregulation on tomato softening, reported during the nineties, minimized the role of this enzyme in softening. Further works in other fruits are challenging this general assumption, as is occurring in strawberry. The strawberry (Fragaria × ananassa) fruit undergoes an extensive and fast softening that limit its shelf life and postharvest. Traditionally, it has also been considered that PG plays a minor role on this process, due to the low PG activity found in ripened strawberry fruits. Transgenic strawberry plants expressing an antisense sequence of the ripening-specific PG gene FaPG1 have been generated to get an insight into the role of this gene in softening. Half of the transgenic lines analyzed yielded fruits significantly firmer than control, without being affected other fruit parameters such as weight, color or soluble solids. The increase on firmness was maintained after several days of posharvest. In these firmer lines, FaPG1 was silenced to 95%, but total PG activity was only minor reduced. At the cell wall level, transgenic fruits contained a higher amount of covalently bound pectins whereas the soluble fraction was diminished. A microarray analysis of genes expressed in ripened receptacle did not show any significant change between control and transgenic fruits. Thus, contrary to the most accepted view, it is concluded that PG plays a key role on pectin metabolism and softening of strawberry fruit. PMID:19820312
The polygalacturonase FaPG1 gene plays a key role in strawberry fruit softening.
García-Gago, Juan A; Posé, Sara; Muñoz-Blanco, Juan; Quesada, Miguel A; Mercado, José A
2009-08-01
The loss of firm texture is one of the most characteristic physiological processes that occur during the ripening of fleshy fruits. It is generally accepted that the disassembly of primary cell wall and middle lamella is the main factor involved in fruit softening. In this process, polygalacturonase (PG) has been implicated in the degradation of the polyuronide network in several fruits. However, the minor effect of PG downregulation on tomato softening, reported during the nineties, minimized the role of this enzyme in softening. Further works in other fruits are challenging this general assumption, as is occurring in strawberry. The strawberry (Fragaria x ananassa) fruit undergoes an extensive and fast softening that limit its shelf life and postharvest. Traditionally, it has also been considered that PG plays a minor role on this process, due to the low PG activity found in ripened strawberry fruits. Transgenic strawberry plants expressing an antisense sequence of the ripening-specific PG gene FaPG1 have been generated to get an insight into the role of this gene in softening. Half of the transgenic lines analyzed yielded fruits significantly firmer than control, without being affected other fruit parameters such as weight, color or soluble solids. The increase on firmness was maintained after several days of posharvest. In these firmer lines, FaPG1 was silenced to 95%, but total PG activity was only minor reduced. At the cell wall level, transgenic fruits contained a higher amount of covalently bound pectins whereas the soluble fraction was diminished. A microarray analysis of genes expressed in ripened receptacle did not show any significant change between control and transgenic fruits. Thus, contrary to the most accepted view, it is concluded that PG plays a key role on pectin metabolism and softening of strawberry fruit.
Radionuclides, trace elements, and radium residence in phosphogypsum of Jordan
Zielinski, R.A.; Al-Hwaiti, M. S.; Budahn, J.R.; Ranville, J.F.
2011-01-01
Voluminous stockpiles of phosphogypsum (PG) generated during the wet process production of phosphoric acid are stored at many sites around the world and pose problems for their safe storage, disposal, or utilization. A major concern is the elevated concentration of long-lived 226Ra (half-life = 1,600 years) inherited from the processed phosphate rock. Knowledge of the abundance and mode-of-occurrence of radium (Ra) in PG is critical for accurate prediction of Ra leachability and radon (Rn) emanation, and for prediction of radiation-exposure pathways to workers and to the public. The mean (??SD) of 226Ra concentrations in ten samples of Jordan PG is 601 ?? 98 Bq/kg, which falls near the midrange of values reported for PG samples collected worldwide. Jordan PG generally shows no analytically significant enrichment (< 10%) of 226Ra in the finer (< 53 ??m) grain size fraction. Phosphogypsum samples collected from two industrial sites with different sources of phosphate rock feedstock show consistent differences in concentration of 226Ra and rare earth elements, and also consistent trends of enrichment in these elements with increasing age of PG. Water-insoluble residues from Jordan PG constitute <10% of PG mass but contain 30-65% of the 226Ra. 226Ra correlates closely with Ba in the water-insoluble residues. Uniformly tiny (< 10 ??m) grains of barite (barium sulfate) observed with scanning electron microscopy have crystal morphologies that indicate their formation during the wet process. Barite is a well-documented and efficient scavenger of Ra from solution and is also very insoluble in water and mineral acids. Radium-bearing barite in PG influences the environmental mobility of radium and the radiation-exposure pathways near PG stockpiles. ?? 2010 US Government.
Influence of motion picture rating on adolescent response to movie smoking.
Sargent, James D; Tanski, Susanne; Stoolmiller, Mike
2012-08-01
To examine the association between movie smoking exposure (MSE) and adolescent smoking according to rating category. A total of 6522 US adolescents were enrolled in a longitudinal survey conducted at 8-month intervals; 5503 subjects were followed up at 8 months, 5019 subjects at 16 months, and 4575 subjects at 24 months. MSE was estimated from 532 recent box-office hits, blocked into 3 Motion Picture Association of America rating categories: G/PG, PG-13, and R. A survival model evaluated time to smoking onset. Median MSE in PG-13-rated movies was ∼3 times higher than median MSE from R-rated movies, but their relation with smoking was essentially the same, with adjusted hazard ratios of 1.49 (95% confidence interval [CI]: 1.23-1.81) and 1.33 (95% CI: 1.23-1.81) for each additional 500 occurrences of MSE respectively. MSE from G/PG-rated movies was small and had no significant relationship with adolescent smoking. Attributable risk estimates showed that adolescent smoking would be reduced by 18% (95% CI: 14-21) if smoking in PG-13-rated movies was reduced to the fifth percentile. In comparison, making all parents maximally authoritative in their parenting would reduce adolescent smoking by 16% (95% CI: 12-19). The equivalent effect of PG-13-rated and R-rated MSE suggests it is the movie smoking that prompts adolescents to smoke, not other characteristics of R-rated movies or adolescents drawn to them. An R rating for movie smoking could substantially reduce adolescent smoking by eliminating smoking from PG-13 movies.
Thill, Marc; Fischer, Dorothea; Kelling, Katharina; Hoellen, Friederike; Dittmer, Christine; Hornemann, Amadeus; Salehin, Darius; Diedrich, Klaus; Friedrich, Michael; Becker, Steffi
2010-07-01
Ovarian carcinomas are associated with increased inflammation which is based upon an up-regulation of inducible cyclooxygenase-2 (COX-2). Moreover, based on our previous published data, the extra-renal vitamin D metabolism seems to be dysregulated in comparison to healthy tissue. In order to gain further insight into the prostaglandin (PG)- and vitamin D-metabolism in ovarian carcinomas, the study aimed to evaluate the expression of the PG metabolising enzymes COX-2 and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) compared to the vitamin D receptor (VDR) in benign and malignant ovarian tissues. Additionally, we determined the 25-hydroxycholecalciferol (25(OH2)D3) serum levels. Expression of VDR, COX-2 and 15-PGDH was determined by Western blot analysis. Serum levels of 25(OH2)D3 and PGE2 were measured by chemiluminescence-based and colorimetric immunoassay. We detected significantly higher expressions of the PG metabolising enzymes 15-PGDH and COX-2 in malignant tissue and PGE2 serum levels were 2-fold higher in tumour patients. Furthermore, we found an inverse correlation to the VDR-expression which was 62.1% lower in malignant tissues compared to that in benign tissues. Surprisingly, we could not detect any differences between the 25(OH2)D3 serum levels in either group (n=20). These data suggest a correlation between PG- and vitamin D-metabolism in ovarian carcinomas. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
Phosalone-induced inflammation and oxidative stress in the colon: Evaluation and treatment.
Ghasemi-Niri, Seyedeh Farnaz; Maqbool, Faheem; Baeeri, Maryam; Gholami, Mahdi; Abdollahi, Mohammad
2016-06-07
To investigate the side effects of phosalone on intestinal cells and to evaluate benefits of ellagic acid (EA) as a remedy. In order to conduct an in vivo study, a rat model was used. The rats were divided into ten groups based on the materials used in the experiment and their dosage. The first group was fed normally. The second group was administered EA through gavage. Next Four groups were given (1/3, 1/5, 1/10, 1/20) LD50 phosalone; an organophosphorus compound. The last four groups received (1/3, 1/5, 1/10, 1/20) LD50 phosalone and of EA. After one month, the rats were sacrificed and their colon cells were examined to evaluate the level of inflammation, proteins and oxidative stress markers. The results of this research show that phosalone elevates oxidative stress and changes the level of tumor necrosis factor-a (TNF-α), interlukin-6β (IL-6β) and nuclear factor (NF)-κB proteins. EA administration reduced phosalone toxicity and changed oxidative stress and inflammatory markers for all phosalone doses. Overall changes in reduction of TNF-α (230.47 ± 16.55 pg/mg protein vs 546.43 ± 45.24 pg/mg protein, P < 0.001), IL-6β (15.85 ± 1.03 pg/mg protein vs 21.55 ± 1.3 pg/mg protein, P < 0.05), and NF-κB (32.47 ± 4.85 pg/mg protein vs 51.41 ± 0.71 pg/mg protein, P < 0.05) manifest that the efficacy of EA is more viable for 1/3 LD50 dose of phosalone. Furthermore, EA is effective to counteract the negative outcomes of oxidative stress. When EA was used to treat 1/3 LD50 of phosalone's side effects, it improved the level of AChE activity (48.5% ± 6% vs 25% ± 7%, P < 0.05), TTM (0.391 ± 0.008 mmol/L vs 0.249 ± 0.032 mmol/L, P < 0.05), FRAP (46.04 ± 5.005 μmol/L vs 18.22 ± 1.9 μmol/L, P < 0.01) and MPO (0.222 ± 0.019 U/mg protein vs 0.387 ± 0.04 U/mg protein, P < 0.05). This research highlights that EA is effective to alleviate the side effects of phosalone by reducing the level of oxidative stress and inflammatory proteins.
Phosalone-induced inflammation and oxidative stress in the colon: Evaluation and treatment
Ghasemi-Niri, Seyedeh Farnaz; Maqbool, Faheem; Baeeri, Maryam; Gholami, Mahdi; Abdollahi, Mohammad
2016-01-01
AIM: To investigate the side effects of phosalone on intestinal cells and to evaluate benefits of ellagic acid (EA) as a remedy. METHODS: In order to conduct an in vivo study, a rat model was used. The rats were divided into ten groups based on the materials used in the experiment and their dosage. The first group was fed normally. The second group was administered EA through gavage. Next Four groups were given (1/3, 1/5, 1/10, 1/20) LD50 phosalone; an organophosphorus compound. The last four groups received (1/3, 1/5, 1/10, 1/20) LD50 phosalone and of EA. After one month, the rats were sacrificed and their colon cells were examined to evaluate the level of inflammation, proteins and oxidative stress markers. RESULTS: The results of this research show that phosalone elevates oxidative stress and changes the level of tumor necrosis factor-a (TNF-α), interlukin-6β (IL-6β) and nuclear factor (NF)-κB proteins. EA administration reduced phosalone toxicity and changed oxidative stress and inflammatory markers for all phosalone doses. Overall changes in reduction of TNF-α (230.47 ± 16.55 pg/mg protein vs 546.43 ± 45.24 pg/mg protein, P < 0.001), IL-6β (15.85 ± 1.03 pg/mg protein vs 21.55 ± 1.3 pg/mg protein, P < 0.05), and NF-κB (32.47 ± 4.85 pg/mg protein vs 51.41 ± 0.71 pg/mg protein, P < 0.05) manifest that the efficacy of EA is more viable for 1/3 LD50 dose of phosalone. Furthermore, EA is effective to counteract the negative outcomes of oxidative stress. When EA was used to treat 1/3 LD50 of phosalone’s side effects, it improved the level of AChE activity (48.5% ± 6% vs 25% ± 7%, P < 0.05), TTM (0.391 ± 0.008 mmol/L vs 0.249 ± 0.032 mmol/L, P < 0.05), FRAP (46.04 ± 5.005 μmol/L vs 18.22 ± 1.9 μmol/L, P < 0.01) and MPO (0.222 ± 0.019 U/mg protein vs 0.387 ± 0.04 U/mg protein, P < 0.05). CONCLUSION: This research highlights that EA is effective to alleviate the side effects of phosalone by reducing the level of oxidative stress and inflammatory proteins. PMID:27275092
Spectral types of four binaries based on photometric observations
NASA Astrophysics Data System (ADS)
Shimanskii, V. V.; Bikmaev, I. F.; Borisov, N. V.; Vlasyuk, V. V.; Galeev, A. I.; Sakhibullin, N. A.; Spiridonova, O. I.
2008-09-01
We present results of photometric and spectroscopic observations of four close binaries with subdwarf B components: PG 0918+029, PG 1000+408, PG 1116+301, PG 0001+275. We discovered that PG 1000+408 is a close binary, with the most probable orbital period being P orb = 1.041145 day. Based on a comparison of the observed light curves at selected orbital phases and theoretical predictions for their variations, all the systems are classified as doubly degenerate binaries with low-luminosity white-dwarf secondaries.
Julkunen, Petro; Kiviranta, Panu; Wilson, Wouter; Jurvelin, Jukka S; Korhonen, Rami K
2007-01-01
Load-bearing characteristics of articular cartilage are impaired during tissue degeneration. Quantitative microscopy enables in vitro investigation of cartilage structure but determination of tissue functional properties necessitates experimental mechanical testing. The fibril-reinforced poroviscoelastic (FRPVE) model has been used successfully for estimation of cartilage mechanical properties. The model includes realistic collagen network architecture, as shown by microscopic imaging techniques. The aim of the present study was to investigate the relationships between the cartilage proteoglycan (PG) and collagen content as assessed by quantitative microscopic findings, and model-based mechanical parameters of the tissue. Site-specific variation of the collagen network moduli, PG matrix modulus and permeability was analyzed. Cylindrical cartilage samples (n=22) were harvested from various sites of the bovine knee and shoulder joints. Collagen orientation, as quantitated by polarized light microscopy, was incorporated into the finite-element model. Stepwise stress-relaxation experiments in unconfined compression were conducted for the samples, and sample-specific models were fitted to the experimental data in order to determine values of the model parameters. For comparison, Fourier transform infrared imaging and digital densitometry were used for the determination of collagen and PG content in the same samples, respectively. The initial and strain-dependent fibril network moduli as well as the initial permeability correlated significantly with the tissue collagen content. The equilibrium Young's modulus of the nonfibrillar matrix and the strain dependency of permeability were significantly associated with the tissue PG content. The present study demonstrates that modern quantitative microscopic methods in combination with the FRPVE model are feasible methods to characterize the structure-function relationships of articular cartilage.
Kent, Michael S.; La Bauve, Elisa; Vernon, Briana C.; ...
2016-02-01
Here, we describe a new method to measure the activation energy required to remove a strongly-bound membrane-associated protein from a lipid membrane (anchoring energy). It is based on measuring the rate of release of a liposome-bound protein during centrifugation on a sucrose gradient as a function of time and temperature. The method was used to determine anchoring energy for the soluble dengue virus envelope protein (sE) strongly bound to 80:20 POPC:POPG liposomes at pH 5.5. We also measured the binding energy of sE at the same pH for the initial, predominantly reversible, phase of binding to a 70:30 PC:PG lipidmore » bilayer. The anchoring energy (37 +/- 1.7 kcal/mol, 20% PG) was found to be much larger than the binding energy (7.8 +/- 0.3 kcal/mol for 30% PG, or est. 7.0 kcal/mol for 20% PG). This is consistent with data showing that free sE is a monomer at pH 5.5, but assembles into trimers after associating with membranes. But, trimerization alone is insufficient to account for the observed difference in energies, and we conclude that some energy dissipation occurs during the release process. This new method to determine anchoring energy should be useful to understand the complex interactions of integral monotopic proteins and strongly-bound peripheral membrane proteins with lipid membranes.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kent, Michael S.; La Bauve, Elisa; Vernon, Briana C.
Here, we describe a new method to measure the activation energy required to remove a strongly-bound membrane-associated protein from a lipid membrane (anchoring energy). It is based on measuring the rate of release of a liposome-bound protein during centrifugation on a sucrose gradient as a function of time and temperature. The method was used to determine anchoring energy for the soluble dengue virus envelope protein (sE) strongly bound to 80:20 POPC:POPG liposomes at pH 5.5. We also measured the binding energy of sE at the same pH for the initial, predominantly reversible, phase of binding to a 70:30 PC:PG lipidmore » bilayer. The anchoring energy (37 +/- 1.7 kcal/mol, 20% PG) was found to be much larger than the binding energy (7.8 +/- 0.3 kcal/mol for 30% PG, or est. 7.0 kcal/mol for 20% PG). This is consistent with data showing that free sE is a monomer at pH 5.5, but assembles into trimers after associating with membranes. But, trimerization alone is insufficient to account for the observed difference in energies, and we conclude that some energy dissipation occurs during the release process. This new method to determine anchoring energy should be useful to understand the complex interactions of integral monotopic proteins and strongly-bound peripheral membrane proteins with lipid membranes.« less
2008-11-01
cancer cell survival, post-androgen withdrawal Task 1. To obtain BM18 tumor tissue that has regressed post-androgen withdrawal +/- IL-6...for analysis of IL-6 pathway molecules. Remaining tumor tissue was processed for routine histology and stained with Masson’s Trichome (Fig 2): - 7...recombinant human IL-6 or TSU xenografts yielded sera with detectable human IL-6 levels by ELISA (3pg/mL and 30pg/mL, respectively) (Twillie et al
Balodis, Iris M.; Kober, Hedy; Worhunsky, Patrick D.; Stevens, Michael C.; Pearlson, Godfrey D.; Potenza, Marc N.
2012-01-01
Background Mesocorticolimbic neurocircuitry and impulsivity have both been implicated in pathological gambling (PG) and in reward processing. However, the neural underpinnings of specific phases of reward and loss processing in PG and their relationships to impulsivity remain only partially understood. The present functional magnetic resonance imaging study examined brain activity associated with different phases of reward and loss processing in PG. Given an inverse relationship between ventral striatal recruitment during anticipation of monetary rewards and impulsivity in alcohol dependence, the current study explored whether a similar association might also be present in PG. Methods Fourteen adults with PG and 14 control comparison (CC) participants performed the Monetary Incentive Delay Task (MIDT) to identify brain activation changes associated with reward/loss prospect, reward/loss anticipation and reward/loss notification. Impulsivity was assessed separately using the Barratt Impulsiveness Scale. Results Relative to the CC group, the PG group exhibited significantly reduced activity in the ventromedial prefrontal cortex, insula and ventral striatum during several phases, including the prospect and anticipation phases of both gain and losses. Activity in the ventral striatum correlated inversely with levels of impulsivity in PG participants, consistent with prior findings in alcohol dependence. Conclusions Relatively decreased activity in cortico-striatal neurocircuitry during multiple phases of reward processing suggests consistent alterations in neurocircuitry underlying incentive valuation and loss prediction. Together with findings in alcohol dependence, these results suggest that impulsive tendencies in addictions may be reflected in diminished ventral striatal activations to reward anticipation and may represent targets for treatment development in addictions. PMID:22336565
Balodis, Iris M; Kober, Hedy; Worhunsky, Patrick D; Stevens, Michael C; Pearlson, Godfrey D; Potenza, Marc N
2012-04-15
Mesocorticolimbic neurocircuitry and impulsivity have both been implicated in pathological gambling (PG) and in reward processing. However, the neural underpinnings of specific phases of reward and loss processing in PG and their relationships to impulsivity remain only partially understood. The present functional magnetic resonance imaging study examined brain activity associated with different phases of reward and loss processing in PG. Given an inverse relationship between ventral striatal recruitment during anticipation of monetary rewards and impulsivity in alcohol dependence, the current study explored whether a similar association might also be present in PG. Fourteen adults with PG and 14 control comparison participants performed the Monetary Incentive Delay Task to identify brain activation changes associated with reward/loss prospect, reward/loss anticipation, and reward/loss notification. Impulsivity was assessed separately using the Barratt Impulsiveness Scale. Relative to the control comparison group, the PG group exhibited significantly reduced activity in the ventromedial prefrontal cortex, insula, and ventral striatum during several phases, including the prospect and anticipation phases of both gains and losses. Activity in the ventral striatum correlated inversely with levels of impulsivity in PG participants, consistent with prior findings in alcohol dependence. Relatively decreased activity in corticostriatal neurocircuitry during multiple phases of reward processing suggests consistent alterations in neurocircuitry underlying incentive valuation and loss prediction. Together with findings in alcohol dependence, these results suggest that impulsive tendencies in addictions may be reflected in diminished ventral striatal activations to reward anticipation and may represent targets for treatment development in addictions. Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
The use of prostaglandins in controlling estrous cycle of the ewe: a review.
Fierro, Sergio; Gil, Jorge; Viñoles, Carolina; Olivera-Muzante, Julio
2013-02-01
This review considers the use of prostaglandin F(2α) and its synthetic analogues (PG) for controlling the estrous cycle of the ewe. Aspects such as phase of the estrus cycle, PG analogues, PG doses, ovarian follicle development pattern, CL formation, progesterone synthesis, ovulation rate, sperm transport, embryo quality, and fertility rates after PG administration are reviewed. Furthermore, protocols for estrus synchronization and their success in timed AI programs are discussed. Based on available information, the ovine CL is refractory to PG treatment for up to 2 days after ovulation. All PG analogues are effective when an appropriate dose is given; in that regard, there is a positive association between the dose administered and the proportion of ewes detected in estrus. Follicular response after PG is dependent on the phase of the estrous cycle at treatment. Altered sperm transport and low pregnancy rates are generally reported. However, reports on alteration of the steroidogenic capacity of preovulatory follicles, ovulation rate, embryo quality, recovery rates, and prolificacy, are controversial. Although various PG-based protocols can be used for estrus synchronization, a second PG injection improves estrus response when the stage of the estrous cycle at the first injection is unknown. The estrus cycle after PG administration has a normal length. Prostaglandin-based protocols for timed AI achieved poor reproductive outcomes, but increasing the interval between PG injections might increase pregnancy rates. Attempts to improve reproductive outcomes have been directed to provide a synchronized LH surge: use of different routes of AI (cervical or intrauterine), different PG doses, and increased intervals between PG injections. Finally we present our point of view regarding future perspectives on the use of PG in programs of controlled sheep reproduction. Copyright © 2013 Elsevier Inc. All rights reserved.
Impacts of urbanization on carbon balance in terrestrial ecosystems of the Southern United States.
Zhang, Chi; Tian, Hanqin; Chen, Guangsheng; Chappelka, Arthur; Xu, Xiaofeng; Ren, Wei; Hui, Dafeng; Liu, Mingliang; Lu, Chaoqun; Pan, Shufen; Lockaby, Graeme
2012-05-01
Using a process-based Dynamic Land Ecosystem Model, we assessed carbon dynamics of urbanized/developed lands in the Southern United States during 1945-2007. The results indicated that approximately 1.72 (1.69-1.77) Pg (1P = 10(15)) carbon was stored in urban/developed lands, comparable to the storage of shrubland or cropland in the region. Urbanization resulted in a release of 0.21 Pg carbon to the atmosphere during 1945-2007. Pre-urbanization vegetation type and time since land conversion were two primary factors determining the extent of urbanization impacts on carbon dynamics. After a rapid decline of carbon storage during land conversion, an urban ecosystem gradually accumulates carbon and may compensate for the initial carbon loss in 70-100 years. The carbon sequestration rate of urban ecosystem diminishes with time, nearly disappearing in two centuries after land conversion. This study implied that it is important to take urbanization effect into account for assessing regional carbon balance. Published by Elsevier Ltd.
Andrew, Marion; Barua, Reeta; Short, Steven M.; Kohn, Linda M.
2012-01-01
The Sclerotiniaceae (Ascomycotina, Leotiomycetes) is a relatively recently evolved lineage of necrotrophic host generalists, and necrotrophic or biotrophic host specialists, some latent or symptomless. We hypothesized that they inherited a basic toolbox of genes for plant symbiosis from their common ancestor. Maintenance and evolutionary diversification of symbiosis could require selection on toolbox genes or on timing and magnitude of gene expression. The genes studied were chosen because their products have been previously investigated as pathogenicity factors in the Sclerotiniaceae. They encode proteins associated with cell wall degradation: acid protease 1 (acp1), aspartyl protease (asps), and polygalacturonases (pg1, pg3, pg5, pg6), and the oxalic acid (OA) pathway: a zinc finger transcription factor (pac1), and oxaloacetate acetylhydrolase (oah), catalyst in OA production, essential for full symptom production in Sclerotinia sclerotiorum. Site-specific likelihood analyses provided evidence for purifying selection in all 8 pathogenicity-related genes. Consistent with an evolutionary arms race model, positive selection was detected in 5 of 8 genes. Only generalists produced large, proliferating disease lesions on excised Arabidopsis thaliana leaves and oxalic acid by 72 hours in vitro. In planta expression of oah was 10–300 times greater among the necrotrophic host generalists than necrotrophic and biotrophic host specialists; pac1 was not differentially expressed. Ability to amplify 6/8 pathogenicity related genes and produce oxalic acid in all genera are consistent with the common toolbox hypothesis for this gene sample. That our data did not distinguish biotrophs from necrotrophs is consistent with 1) a common toolbox based on necrotrophy and 2) the most conservative interpretation of the 3-locus housekeeping gene phylogeny – a baseline of necrotrophy from which forms of biotrophy emerged at least twice. Early oah overexpression likely expands the host range of necrotrophic generalists in the Sclerotiniaceae, while specialists and biotrophs deploy oah, or other as-yet-unknown toolbox genes, differently. PMID:22253834
A generalized preferential attachment model for business firms growth rates. I. Empirical evidence
NASA Astrophysics Data System (ADS)
Pammolli, F.; Fu, D.; Buldyrev, S. V.; Riccaboni, M.; Matia, K.; Yamasaki, K.; Stanley, H. E.
2007-05-01
We introduce a model of proportional growth to explain the distribution P(g) of business firm growth rates. The model predicts that P(g) is Laplace in the central part and depicts an asymptotic power-law behavior in the tails with an exponent ζ = 3. Because of data limitations, previous studies in this field have been focusing exclusively on the Laplace shape of the body of the distribution. We test the model at different levels of aggregation in the economy, from products, to firms, to countries, and we find that the predictions are in good agreement with empirical evidence on both growth distributions and size-variance relationships.
From the Cover: The growth of business firms: Theoretical framework and empirical evidence
NASA Astrophysics Data System (ADS)
Fu, Dongfeng; Pammolli, Fabio; Buldyrev, S. V.; Riccaboni, Massimo; Matia, Kaushik; Yamasaki, Kazuko; Stanley, H. Eugene
2005-12-01
We introduce a model of proportional growth to explain the distribution Pg(g) of business-firm growth rates. The model predicts that Pg(g) is exponential in the central part and depicts an asymptotic power-law behavior in the tails with an exponent = 3. Because of data limitations, previous studies in this field have been focusing exclusively on the Laplace shape of the body of the distribution. In this article, we test the model at different levels of aggregation in the economy, from products to firms to countries, and we find that the predictions of the model agree with empirical growth distributions and size-variance relationships. proportional growth | preferential attachment | Laplace distribution
Bulathsinghala, Marie; Keefer, Kimberly; Van de Louw, Andry
2016-04-01
Propylene glycol (PG) is used as a solvent in numerous medications, including trimethoprim/sulfamethoxazole (TMP/SMX) and lorazepam, and is metabolized in the liver to lactic acid. Cases of lactic acidosis related to PG toxicity have been described and always involved large doses of benzodiazepines and PG. We present the first case of severe lactic acidosis after a 3-day course of TMP/SMX alone, involving allegedly safe amounts of PG.A 31-year-old female with neurofibromatosis and pilocytic astrocytoma, receiving temozolomide and steroids, was admitted to the intensive care unit for pneumonia and acute respiratory failure requiring intubation. Her initial hemodynamic and acid-base statuses were normal. She was treated with intravenous TMP/SMX for possible Pneumocystis jirovecii pneumonia and was successfully extubated on day 2. On day 3, she developed tachypnea and arterial blood gas analysis revealed a severe metabolic acidosis (pH 7.2, PCO2 19 mm Hg, bicarbonates 8 mEq/L) with anion gap of 25 mEq/L and lactate of 12.1 mmol/L. TMP/SMX was discontinued and the lactate decreased to 2.9 mmol/L within 24 hours while her plasma bicarbonates normalized, without additional intervention. The patient never developed hypotension or severe hypoxia, and her renal and liver functions were normal. No other cause for lactic acidosis was identified and it resolved after TMP/SMX cessation alone, suggesting PG toxicity.Although PG-related lactic acidosis is well recognized after large doses of lorazepam, clinicians should bear in mind that TMP/SMX contains PG as well and should suspect PG toxicity in patients developing unexplained metabolic acidosis while receiving TMP/SMX.
Ohnishi, M; Thompson, G A
1991-08-01
As in most higher plants, chloroplast membranes of the green alga Dunaliella salina contain phosphatidylglycerol (PG) that is rich in trans-delta 3-hexadecenoic acid (16:1t), a fatty acid found nowhere else in the cell. After labeling D. salina with exogenous [3H]myristic acid [( 3H]14:0), the cis-unsaturated fatty acids of monogalactosyldiacylglycerol and sulfoquinovosyldiacylglycerol as well as PG had higher specific radioactivities in chloroplast envelopes than in thylakoids. In contrast, 16:1t was very slow to become radioactive, and its specific radioactivity was several times higher in isolated thylakoids than in envelopes after brief (3-20 min) labeling with [3H]14:0. Analysis of individual PG molecular species revealed that the fatty acid paired with 16:1t was also labeled slowly. Thus linoleate (18:2) released from a 16:1t-containing PG had a 350-fold (at 3 min) to 20-fold (at 60 min) lower specific radioactivity than did 18:2 from a palmitate (16:0)-containing PG. The findings suggest that the substrates for trans-desaturation are 16:0-containing PG molecular species which are readily labeled from [3H]14:0 in the envelope but are diluted by the large pool of thylakoid PG before penetrating to the desaturation site. By examining the labeling patterns of individual PG molecular species classes, it was concluded that D. salina 16:1t is formed from 16:0 linked to 18:2/16:0 PG and 18:3/16:0 PG by a trans-desaturase located within the inner recesses of the thylakoid compartment.
van Baren, Marijke J; Bachy, Charles; Reistetter, Emily Nahas; Purvine, Samuel O; Grimwood, Jane; Sudek, Sebastian; Yu, Hang; Poirier, Camille; Deerinck, Thomas J; Kuo, Alan; Grigoriev, Igor V; Wong, Chee-Hong; Smith, Richard D; Callister, Stephen J; Wei, Chia-Lin; Schmutz, Jeremy; Worden, Alexandra Z
2016-03-31
Prasinophytes are widespread marine green algae that are related to plants. Cellular abundance of the prasinophyte Micromonas has reportedly increased in the Arctic due to climate-induced changes. Thus, studies of these unicellular eukaryotes are important for marine ecology and for understanding Viridiplantae evolution and diversification. We generated evidence-based Micromonas gene models using proteomics and RNA-Seq to improve prasinophyte genomic resources. First, sequences of four chromosomes in the 22 Mb Micromonas pusilla (CCMP1545) genome were finished. Comparison with the finished 21 Mb genome of Micromonas commoda (RCC299; named herein) shows they share ≤8,141 of ~10,000 protein-encoding genes, depending on the analysis method. Unlike RCC299 and other sequenced eukaryotes, CCMP1545 has two abundant repetitive intron types and a high percent (26 %) GC splice donors. Micromonas has more genus-specific protein families (19 %) than other genome sequenced prasinophytes (11 %). Comparative analyses using predicted proteomes from other prasinophytes reveal proteins likely related to scale formation and ancestral photosynthesis. Our studies also indicate that peptidoglycan (PG) biosynthesis enzymes have been lost in multiple independent events in select prasinophytes and plants. However, CCMP1545, polar Micromonas CCMP2099 and prasinophytes from other classes retain the entire PG pathway, like moss and glaucophyte algae. Surprisingly, multiple vascular plants also have the PG pathway, except the Penicillin-Binding Protein, and share a unique bi-domain protein potentially associated with the pathway. Alongside Micromonas experiments using antibiotics that halt bacterial PG biosynthesis, the findings highlight unrecognized phylogenetic complexity in PG-pathway retention and implicate a role in chloroplast structure or division in several extant Viridiplantae lineages. Extensive differences in gene loss and architecture between related prasinophytes underscore their divergence. PG biosynthesis genes from the cyanobacterial endosymbiont that became the plastid, have been selectively retained in multiple plants and algae, implying a biological function. Our studies provide robust genomic resources for emerging model algae, advancing knowledge of marine phytoplankton and plant evolution.
Clark, Luke; Stokes, Paul R.; Wu, Kit; Michalczuk, Rosanna; Benecke, Aaf; Watson, Ben J.; Egerton, Alice; Piccini, Paola; Nutt, David J.; Bowden-Jones, Henrietta; Lingford-Hughes, Anne R.
2012-01-01
Pathological gambling (PG) is a behavioural addiction associated with elevated impulsivity and suspected dopamine dysregulation. Reduced striatal dopamine D2/D3 receptor availability has been reported in drug addiction, and may constitute a premorbid vulnerability marker for addictive disorders. The aim of the present study was to assess striatal dopamine D2/D3 receptor availability in PG, and its association with trait impulsivity. Males with PG (n = 9) and male healthy controls (n = 9) underwent [11C]-raclopride positron emission tomography imaging and completed the UPPS-P impulsivity scale. There was no significant difference between groups in striatal dopamine D2/D3 receptor availability, in contrast to previous reports in drug addiction. However, mood-related impulsivity (‘Urgency’) was negatively correlated with [11C]-raclopride binding potentials in the PG group. The absence of a group difference in striatal dopamine binding implies a distinction between behavioural addictions and drug addictions. Nevertheless, our data indicate heterogeneity in dopamine receptor availability in disordered gambling, such that individuals with high mood-related impulsivity may show differential benefits from dopamine-based medications. PMID:22776462
Hardy, I J; Cook, W G; Melia, C D
2006-03-27
The compression and compaction properties of plasticised high molecular weight USP2208 HPMC were investigated with the aim of improving tablet formation in HPMC matrices. Experiments were conducted on binary polymer-plasticiser mixtures containing 17 wt.% plasticiser, and on a model hydrophilic matrix formulation. A selection of common plasticisers, propylene glycol (PG) glycerol (GLY), dibutyl sebacate (DBS) and triacetin (TRI), were chosen to provide a range of plasticisation efficiencies. T(g) values of binary mixtures determined by Dynamic Mechanical Thermal Analysis (DMTA) were in rank order PG>GLY>DBS>TRI>unplasticised HPMC. Mean yield pressure, strain rate sensitivity (SRS) and plastic compaction energy were measured during the compression process, and matrix properties were monitored by tensile strength and axial expansion post-compression. Compression of HPMC:PG binary mixtures resulted in a marked reduction in mean yield pressure and a significant increase in SRS, suggesting a classical plasticisation of HPMC analogous to that produced by water. The effect of PG was also reflected in matrix properties. At compression pressures below 70 MPa, compacts had greater tensile strength than those from native polymer, and over the range 35 and 70 MPa, lower plastic compaction values showed that less energy was required to produce the compacts. Axial expansion was also reduced. Above 70 MPa tensile strength was limited to 3 MPa. These results suggest a useful improvement of HPMC compaction and matrix properties by PG plasticisation, with lowering of T(g) resulting in improved deformation and internal bonding. These effects were also detectable in the model formulation containing a minimal polymer content for an HPMC matrix. Other plasticisers were largely ineffective, matrix strength was poor and axial expansion high. The hydrophobic plasticisers (DBS, TRI) reduced yield pressure substantially, but were poor plasticisers and showed compaction mechanisms that could be attributed to phase separation. The effect of different plasticisers suggests that the deformation characteristics of this HPMC in the solid state is dominated by hydroxyl mediated bonding, rather than by hydrophobic interactions between methoxyl-rich regions.
Resilience of rice (Oryza spp.) pollen germination and tube growth to temperature stress.
Coast, Onoriode; Murdoch, Alistair J; Ellis, Richard H; Hay, Fiona R; Jagadish, Krishna S V
2016-01-01
Resilience of rice cropping systems to potential global climate change will partly depend on the temperature tolerance of pollen germination (PG) and tube growth (PTG). Pollen germination of high temperature-susceptible Oryza glaberrima Steud. (cv. CG14) and Oryza sativa L. ssp. indica (cv. IR64) and high temperature-tolerant O. sativa ssp. aus (cv. N22), was assessed on a 5.6-45.4 °C temperature gradient system. Mean maximum PG was 85% at 27 °C with 1488 μm PTG at 25 °C. The hypothesis that in each pollen grain, the minimum temperature requirements (Tn ) and maximum temperature limits (Tx ) for germination operate independently was accepted by comparing multiplicative and subtractive probability models. The maximum temperature limit for PG in 50% of grains (Tx(50) ) was the lowest (29.8 °C) in IR64 compared with CG14 (34.3 °C) and N22 (35.6 °C). Standard deviation (sx ) of Tx was also low in IR64 (2.3 °C) suggesting that the mechanism of IR64's susceptibility to high temperatures may relate to PG. Optimum germination temperatures and thermal times for 1 mm PTG were not linked to tolerating high temperatures at anthesis. However, the parameters Tx(50) and sx in the germination model define new pragmatic criteria for successful and resilient PG, preferable to the more traditional cardinal (maximum and minimum) temperatures. © 2014 John Wiley & Sons Ltd.
Serum VEGF-A concentrations in patients with central nervous system (CNS) tumors
2018-01-01
Angiogenesis plays an essential role in tumors development. In case of central nervous system tumors, the most important role in this process plays VEGF-A. The purpose of this study was to determine the plasma concentration of this agent in patients treated surgically because of intracranial tumors. The study involved 48 adult patients, both sexes, treated surgically because of a brain tumor. The control group consisted of 50 adult volunteers of both sexes, without cancer diagnosis. Based on the studies, it was found that serum VEGF-A levels before surgery are higher in patients with central nervous system tumors (10.39–150.57 pg/ml, median 41.70 pg/ml) than in non-cancer patients (0.00–130.77 pg/ml, median 22.56 pg/ml). The association between serum VEGF-A level and malignancy and histological type of intracranial tumor has not beed confirmed. The highest average preoperative serum VEGF-A level was found in patients with low grade gliomas, slightly lower (close to each other) in those with high grade gliomas and meningiomas, while the lowest level was characteristic for metastatic tumors. High variation in results was observed in patients with low grade gliomas (52.56 pg/ml)—higher than those reported in patients with high grade gliomas (32.38 pg/ml). In the rest types of tumors the differentiation was similar and oscillated within 23.08–27.50 pg/ml. PMID:29590109
Liu, Xin; Li, Jun; Zheng, Qian; Bing, Haijian; Zhang, Ruijie; Wang, Yan; Luo, Chunling; Liu, Xiang; Wu, Yanhong; Pan, Suhong; Zhang, Gan
2014-12-16
Mountains are observed to preferentially accumulate persistent organic pollutants (POPs) at higher altitude due to the cold condensation effect. Forest soils characterized by high organic carbon are important for terrestrial storage of POPs. To investigate the dominant factor controlling the altitudinal distribution of POPs in mountainous areas, we measured concentrations of polychlorinated biphenyls (PCBs) in different environmental matrices (soil, moss, and air) from nine elevations on the eastern slope of Mt. Gongga, the highest mountain in Sichuan Province on the Tibetan Plateau. The concentrations of 24 measured PCBs ranged from 41 to 510 pg/g dry weight (dw) (mean: 260 pg/g dw) in the O-horizon soil, 280 to 1200 pg/g dw (mean: 740 pg/g dw) in moss, and 33 to 60 pg/m(3) (mean: 47 pg/m(3)) in air. Soil organic carbon was a key determinant explaining 75% of the variation in concentration along the altitudinal gradient. Across all of the sampling sites, the average contribution of the forest filter effect (FFE) was greater than that of the mountain cold trapping effect based on principal components analysis and multiple linear regression. Our results deviate from the thermodynamic theory involving cold condensation at high altitudes of mountain areas and highlight the importance of the FFE.
Bispo, Marcia S; Veloso, Márcia Cristina C; Pinheiro, Heloísa Lúcia C; De Oliveira, Rodolfo F S; Reis, José Oscar N; De Andrade, Jailson B
2002-01-01
This work relates the development of an analytical methodology to simultaneously determine three methylxanthines (caffeine, theobromine, and theophylline) in beverages and urine samples based on reversed-phase high-performance liquid chromatography. Separation is made with a Bondesil C18 column using methanol-water-acetic acid or ethanol-water-acetic acid (20:75:5, v/v/v) as the mobile phase at 0.7 mL/min. Identification is made by absorbance detection at 273 nm. Under optimized conditions, the detection limit of the HPLC method is 0.1 pg/mL for all three methylxanthines. This method is applied to urine and to 25 different beverage samples, which included coffee, tea, chocolate, and coconut water. The concentration ranges determined in the beverages and urine are: < 0.1 pg/mL to 350 microg/mL and 3.21 microg/mL to 71.2 microg/mL for caffeine; < 0.1 pg/mL to 32 microg mL and < 0.1 pg/mL to 13.2 microg/mL for theobromine; < 0.1 pg/mL to 47 microg/mL and < 0.1 pg/mL to 66.3 microg/mL for theophylline. The method proposed in this study is rapid and suitable for the simultaneous quantitation of methylxanthines in beverages and human urine samples and requires no extraction step or derivatization.
NASA Astrophysics Data System (ADS)
Shao, Junjiong; Zhou, Xuhui; Luo, Yiqi; Zhang, Guodong; Yan, Wei; Li, Jiaxuan; Li, Bo; Dan, Li; Fisher, Joshua B.; Gao, Zhiqiang; He, Yong; Huntzinger, Deborah; Jain, Atul K.; Mao, Jiafu; Meng, Jihua; Michalak, Anna M.; Parazoo, Nicholas C.; Peng, Changhui; Poulter, Benjamin; Schwalm, Christopher R.; Shi, Xiaoying; Sun, Rui; Tao, Fulu; Tian, Hanqin; Wei, Yaxing; Zeng, Ning; Zhu, Qiuan; Zhu, Wenquan
2016-05-01
Despite the importance of net primary productivity (NPP) and net biome productivity (NBP), estimates of NPP and NBP for China are highly uncertain. To investigate the main sources of uncertainty, we synthesized model estimates of NPP and NBP for China from published literature and the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP). The literature-based results showed that total NPP and NBP in China were 3.35 ± 1.25 and 0.14 ± 0.094 Pg C yr-1, respectively. Classification and regression tree analysis based on literature data showed that model type was the primary source of the uncertainty, explaining 36% and 64% of the variance in NPP and NBP, respectively. Spatiotemporal scales, land cover conditions, inclusion of the N cycle, and effects of N addition also contributed to the overall uncertainty. Results based on the MsTMIP data suggested that model structures were overwhelmingly important (>90%) for the overall uncertainty compared to simulations with different combinations of time-varying global change factors. The interannual pattern of NPP was similar among diverse studies and increased by 0.012 Pg C yr-1 during 1981-2000. In addition, high uncertainty in China's NPP occurred in areas with high productivity, whereas NBP showed the opposite pattern. Our results suggest that to significantly reduce uncertainty in estimated NPP and NBP, model structures should be substantially tested on the basis of empirical results. To this end, coordinated distributed experiments with multiple global change factors might be a practical approach that can validate specific structures of different models.
Shared Genetic Contributions to Anxiety Disorders and Pathological Gambling in a Male Population
Giddens, Justine L.; Xian, Hong; Scherrer, Jeffrey F.; Eisen, Seth A.; Potenza, Marc N.
2013-01-01
Background Pathological gambling (PG) frequently co-occurs with anxiety disorders. However, the extent to which the co-occurrence is related to genetic or environmental factors across PG and anxiety disorders is not known. Method Data from the Vietnam Twin Registry (n=7869, male twins) were examined in bivariate models to estimate genetic and shared and unique environmental contributions to PG and generalized anxiety disorder (GAD) and PG and panic disorder (PD). Results While both genetic and unique environmental factors contributed individually to PG, GAD, and PD, the best fitting model indicated that the relationship between PG and GAD was attributable predominantly to shared genetic contributions (ra =0.53). In contrast, substantial correlations were observed between both the genetic (ra=0.34) and unique environmental (re =0.31) contributions to PG and PD. Limitations Results may be limited to middle aged males. Conclusions The existence of shared genetic contributions between PG and both GAD and PD suggest that specific genes, perhaps those involved in affect regulation or stress responsiveness, contribute to PG and anxiety disorders. Overlapping environmental contributions to the co-occurrence of PG and PD suggest that common life experiences (e.g., early life trauma) contribute to both PG and PD. Conversely, the data suggest that distinct environmental factors contribute to PG and GAD (e.g., early onset of gambling in PG). Future studies should examine the relationship between PG and anxiety disorders amongst other populations (women, adolescents) to identify specific genetic and environmental influences that account for the manifestation of these disorders and their co-occurrences. PMID:21481943
Shared genetic contributions to anxiety disorders and pathological gambling in a male population.
Giddens, Justine L; Xian, Hong; Scherrer, Jeffrey F; Eisen, Seth A; Potenza, Marc N
2011-08-01
Pathological gambling (PG) frequently co-occurs with anxiety disorders. However, the extent to which the co-occurrence is related to genetic or environmental factors across PG and anxiety disorders is not known. Data from the Vietnam Era Twin Registry (n=7869, male twins) were examined in bivariate models to estimate genetic and shared and unique environmental contributions to PG and generalized anxiety disorder (GAD) and PG and panic disorder (PD). While both genetic and unique environmental factors contributed individually to PG, GAD, and PD, the best fitting model indicated that the relationship between PG and GAD was attributable predominantly to shared genetic contributions (r(A)=0.53). In contrast, substantial correlations were observed between both the genetic (r(A)=0.34) and unique environmental (r(E)=0.31) contributions to PG and PD. Results may be limited to middle aged males. The existence of shared genetic contributions between PG and both GAD and PD suggests that specific genes, perhaps those involved in affect regulation or stress responsiveness, contribute to PG and anxiety disorders. Overlapping environmental contributions to the co-occurrence of PG and PD suggest that common life experiences (e.g., early life trauma) contribute to both PG and PD. Conversely, the data suggest that distinct environmental factors contribute to PG and GAD (e.g., early onset of gambling in PG). Future studies should examine the relationship between PG and anxiety disorders amongst other populations (women and adolescents) to identify specific genetic and environmental influences that account for the manifestation of these disorders and their co-occurrences. Copyright © 2011. Published by Elsevier B.V.
Hypersensitive Ethylene Signaling and ZMdPG1 Expression Lead to Fruit Softening and Dehiscence
Li, Min; Zhang, Yanmin; Zhang, Zongying; Ji, Xiaohao; Zhang, Rui; Liu, Daliang; Gao, Liping; Zhang, Jing; Wang, Biao; Wu, Yusen; Wu, Shujing; Chen, Xiaoliu; Feng, Shouqian; Chen, Xuesen
2013-01-01
‘Taishanzaoxia’ fruit rapid softening and dehiscence during ripening stage and this process is very sensitive to endogenous ethylene. In this study, we cloned five ethylene signal transcription factors (ZMdEIL1, ZMdEIL2, ZMdEIL3, ZMdERF1 and ZMdERF2) and one functional gene, ZMdPG1, encoding polygalacturonase that could loose the cell connection which associated with fruit firmness decrease and fruit dehiscence to illustrate the reasons for this specific fruit phenotypic and physiological changes. Expression analysis showed that ZMdERF1 and ZMdEIL2 transcription were more abundant in ‘Taishanzaoxia’ softening fruit and dehiscent fruit and their expression was inhibited by an ethylene inhibitor 1-methylcyclopropene. Therefore, ZMdERF1 and ZMdEIL2 expression were responses to endogenous ethylene and associated with fruit softening and dehiscence. ZMdPG1 expression was induced when fruit softening and dehiscence but this induction can be blocked by 1-MCP, indicating that ZMdPG1 was essential for fruit softening and dehiscence and its expression was mediated by the endogenously occurred ethylene. ZMdPG1 overexpression in Arabidopsis led to silique early dehiscence while suppressing ZMdPG1 expression by antisense ZMdPG1 prevented silique naturally opening. The result also suggested that ZMdPG1 related with the connection between cells that contributed to fruit softening and dehiscence. ZMdERF1 was more closely related with ethylene signaling but it was not directly regulated the ZMdPG1, which might be regulated by the synergic pattern of ethylene transcription factors because of both the ZMdERF1 and ZMdERF2 could interact with ZMdEIL2. PMID:23527016
Ghio, Marta; Locatelli, Matteo; Tettamanti, Andrea; Perani, Daniela; Gatti, Roberto; Tettamanti, Marco
2018-06-01
Embodied cognition theories of semantic memory still face the need for multiple sources of converging evidence in support of the involvement of sensory-motor systems in action-related knowledge. Previous studies showed that training manual actions improves semantic processing of verbs referring to the trained actions. The present work aimed to provide complementary evidence by measuring the brain plasticity effects of a cognitive training requiring sustained lexical-semantic processing of action-related verbs. We included two groups of participants, namely the Proximal Group (PG) and the Distal Group (DG), which underwent a 3-week training with verbs referring to actions involving the proximal and the distal upper limb musculature, respectively. Before and after training, we measured gray matter voxel brain morphometry based on T1 structural magnetic resonance imaging. By means of this 2 (Group: PG, DG) × 2 (Time: pre-, post-training) factorial design, we tested whether sustained cognitive experience with specific action-related verbs induces congruent brain plasticity modifications in target regions of interest pertaining to the action representation system. We found significant post- versus pre-training gray matter volume increases, specifically for PG in the left dorsal precentral gyrus, and for DG in the right cerebellar lobule VIIa. These preliminary results suggest that a cognitive training can induce structural plasticity modifications in brain regions specifically coding for the distal and proximal motor actions the trained verbs refer to. Copyright © 2018 Elsevier Ltd. All rights reserved.
Pathological gambling recovery in the absence of abstinence.
Slutske, Wendy S; Piasecki, Thomas M; Blaszczynski, Alex; Martin, Nicholas G
2010-12-01
To examine the role of abstinence from gambling versus controlled gambling in recovery from pathological gambling (PG) in a community-based survey. Individuals with a life-time history of PG identified in a community-based survey were divided into three groups based on their current levels of PG symptoms. These three groups were compared to each other on their past-year gambling involvement. National general population twin survey conducted in Australia. Overall, there were 4764 participants in the community-based survey (mean age 37.7 years, 57.2% women). Among these were 104 participants with a life-time history of PG; of the 104 with a life-time diagnosis of PG, 28 had a past-year diagnosis of PG, 32 had past-year problem gambling and 44 had no symptoms of PG in the past year ('recovery'). The measure of PG was based on the NODS (NORC DSM-IV Screen for Gambling Problems). Past-year participation in 11 different gambling activities was assessed, as well as the following composite indicators: any gambling, gambling versatility, the number of days and hours spent gambling and the proportion of household income spent on gambling. Ninety per cent of those in the recovery group participated in some form of gambling in the past year. In this general population survey, nearly all the PG recoveries were achieved in the absence of abstinence. Controlled gambling appears to be a popular road to recovery in the community. © 2010 The Authors, Addiction © 2010 Society for the Study of Addiction.
Carbon sequestration potential of second-growth forest regeneration in the Latin American tropics
Chazdon, Robin L.; Broadbent, Eben N.; Rozendaal, Danaë M. A.; Bongers, Frans; Zambrano, Angélica María Almeyda; Aide, T. Mitchell; Balvanera, Patricia; Becknell, Justin M.; Boukili, Vanessa; Brancalion, Pedro H. S.; Craven, Dylan; Almeida-Cortez, Jarcilene S.; Cabral, George A. L.; de Jong, Ben; Denslow, Julie S.; Dent, Daisy H.; DeWalt, Saara J.; Dupuy, Juan M.; Durán, Sandra M.; Espírito-Santo, Mario M.; Fandino, María C.; César, Ricardo G.; Hall, Jefferson S.; Hernández-Stefanoni, José Luis; Jakovac, Catarina C.; Junqueira, André B.; Kennard, Deborah; Letcher, Susan G.; Lohbeck, Madelon; Martínez-Ramos, Miguel; Massoca, Paulo; Meave, Jorge A.; Mesquita, Rita; Mora, Francisco; Muñoz, Rodrigo; Muscarella, Robert; Nunes, Yule R. F.; Ochoa-Gaona, Susana; Orihuela-Belmonte, Edith; Peña-Claros, Marielos; Pérez-García, Eduardo A.; Piotto, Daniel; Powers, Jennifer S.; Rodríguez-Velazquez, Jorge; Romero-Pérez, Isabel Eunice; Ruíz, Jorge; Saldarriaga, Juan G.; Sanchez-Azofeifa, Arturo; Schwartz, Naomi B.; Steininger, Marc K.; Swenson, Nathan G.; Uriarte, Maria; van Breugel, Michiel; van der Wal, Hans; Veloso, Maria D. M.; Vester, Hans; Vieira, Ima Celia G.; Bentos, Tony Vizcarra; Williamson, G. Bruce; Poorter, Lourens
2016-01-01
Regrowth of tropical secondary forests following complete or nearly complete removal of forest vegetation actively stores carbon in aboveground biomass, partially counterbalancing carbon emissions from deforestation, forest degradation, burning of fossil fuels, and other anthropogenic sources. We estimate the age and spatial extent of lowland second-growth forests in the Latin American tropics and model their potential aboveground carbon accumulation over four decades. Our model shows that, in 2008, second-growth forests (1 to 60 years old) covered 2.4 million km2 of land (28.1% of the total study area). Over 40 years, these lands can potentially accumulate a total aboveground carbon stock of 8.48 Pg C (petagrams of carbon) in aboveground biomass via low-cost natural regeneration or assisted regeneration, corresponding to a total CO2 sequestration of 31.09 Pg CO2. This total is equivalent to carbon emissions from fossil fuel use and industrial processes in all of Latin America and the Caribbean from 1993 to 2014. Ten countries account for 95% of this carbon storage potential, led by Brazil, Colombia, Mexico, and Venezuela. We model future land-use scenarios to guide national carbon mitigation policies. Permitting natural regeneration on 40% of lowland pastures potentially stores an additional 2.0 Pg C over 40 years. Our study provides information and maps to guide national-level forest-based carbon mitigation plans on the basis of estimated rates of natural regeneration and pasture abandonment. Coupled with avoided deforestation and sustainable forest management, natural regeneration of second-growth forests provides a low-cost mechanism that yields a high carbon sequestration potential with multiple benefits for biodiversity and ecosystem services. PMID:27386528
Carbon sequestration potential of second-growth forest regeneration in the Latin American tropics.
Chazdon, Robin L; Broadbent, Eben N; Rozendaal, Danaë M A; Bongers, Frans; Zambrano, Angélica María Almeyda; Aide, T Mitchell; Balvanera, Patricia; Becknell, Justin M; Boukili, Vanessa; Brancalion, Pedro H S; Craven, Dylan; Almeida-Cortez, Jarcilene S; Cabral, George A L; de Jong, Ben; Denslow, Julie S; Dent, Daisy H; DeWalt, Saara J; Dupuy, Juan M; Durán, Sandra M; Espírito-Santo, Mario M; Fandino, María C; César, Ricardo G; Hall, Jefferson S; Hernández-Stefanoni, José Luis; Jakovac, Catarina C; Junqueira, André B; Kennard, Deborah; Letcher, Susan G; Lohbeck, Madelon; Martínez-Ramos, Miguel; Massoca, Paulo; Meave, Jorge A; Mesquita, Rita; Mora, Francisco; Muñoz, Rodrigo; Muscarella, Robert; Nunes, Yule R F; Ochoa-Gaona, Susana; Orihuela-Belmonte, Edith; Peña-Claros, Marielos; Pérez-García, Eduardo A; Piotto, Daniel; Powers, Jennifer S; Rodríguez-Velazquez, Jorge; Romero-Pérez, Isabel Eunice; Ruíz, Jorge; Saldarriaga, Juan G; Sanchez-Azofeifa, Arturo; Schwartz, Naomi B; Steininger, Marc K; Swenson, Nathan G; Uriarte, Maria; van Breugel, Michiel; van der Wal, Hans; Veloso, Maria D M; Vester, Hans; Vieira, Ima Celia G; Bentos, Tony Vizcarra; Williamson, G Bruce; Poorter, Lourens
2016-05-01
Regrowth of tropical secondary forests following complete or nearly complete removal of forest vegetation actively stores carbon in aboveground biomass, partially counterbalancing carbon emissions from deforestation, forest degradation, burning of fossil fuels, and other anthropogenic sources. We estimate the age and spatial extent of lowland second-growth forests in the Latin American tropics and model their potential aboveground carbon accumulation over four decades. Our model shows that, in 2008, second-growth forests (1 to 60 years old) covered 2.4 million km(2) of land (28.1% of the total study area). Over 40 years, these lands can potentially accumulate a total aboveground carbon stock of 8.48 Pg C (petagrams of carbon) in aboveground biomass via low-cost natural regeneration or assisted regeneration, corresponding to a total CO2 sequestration of 31.09 Pg CO2. This total is equivalent to carbon emissions from fossil fuel use and industrial processes in all of Latin America and the Caribbean from 1993 to 2014. Ten countries account for 95% of this carbon storage potential, led by Brazil, Colombia, Mexico, and Venezuela. We model future land-use scenarios to guide national carbon mitigation policies. Permitting natural regeneration on 40% of lowland pastures potentially stores an additional 2.0 Pg C over 40 years. Our study provides information and maps to guide national-level forest-based carbon mitigation plans on the basis of estimated rates of natural regeneration and pasture abandonment. Coupled with avoided deforestation and sustainable forest management, natural regeneration of second-growth forests provides a low-cost mechanism that yields a high carbon sequestration potential with multiple benefits for biodiversity and ecosystem services.
Mikecz, Katalin; Glant, Tibor T; Markovics, Adrienn; Rosenthal, Kenneth S; Kurko, Julia; Carambula, Roy E; Cress, Steve; Steiner, Harold L; Zimmerman, Daniel H
2017-07-13
Rheumatoid arthritis (RA) is an autoimmune joint disease maintained by aberrant immune responses involving CD4+ T helper (Th)1 and Th17 cells. In this study, we tested the therapeutic efficacy of Ligand Epitope Antigen Presentation System (LEAPS™) vaccines in two Th1 cell-driven mouse models of RA, cartilage proteoglycan (PG)-induced arthritis (PGIA) and PG G1-domain-induced arthritis (GIA). The immunodominant PG peptide PG70 was attached to a DerG or J immune cell binding peptide, and the DerG-PG70 and J-PG70 LEAPS vaccines were administered to the mice after the onset of PGIA or GIA symptoms. As indicated by significant decreases in visual and histopathological scores of arthritis, the DerG-PG70 vaccine inhibited disease progression in both PGIA and GIA, while the J-PG70 vaccine was ineffective. Splenic CD4+ cells from DerG-PG70-treated mice were diminished in Th1 and Th17 populations but enriched in Th2 and regulatory T (Treg) cells. In vitro spleen cell-secreted and serum cytokines from DerG-PG70-treated mice demonstrated a shift from a pro-inflammatory to an anti-inflammatory/regulatory profile. DerG-PG70 peptide tetramers preferentially bound to CD4+ T-cells of GIA spleen cells. We conclude that the DerG-PG70 vaccine (now designated CEL-4000) exerts its therapeutic effect by interacting with CD4+ cells, which results in an antigen-specific down-modulation of pathogenic T-cell responses in both the PGIA and GIA models of RA. Future studies will need to determine the potential of LEAPS vaccination to provide disease suppression in patients with RA. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Low-carbon agriculture in South America to mitigate global climate change and advance food security.
Sá, João Carlos de Moraes; Lal, Rattan; Cerri, Carlos Clemente; Lorenz, Klaus; Hungria, Mariangela; de Faccio Carvalho, Paulo Cesar
2017-01-01
The worldwide historical carbon (C) losses due to Land Use and Land-Use Change between 1870 and 2014 are estimated at 148 Pg C (1 Pg=1billionton). South America is chosen for this study because its soils contain 10.3% (160 Pg C to 1-m depth) of the soil organic carbon stock of the world soils, it is home to 5.7% (0.419 billion people) of the world population, and accounts for 8.6% of the world food (491milliontons) and 21.0% of meat production (355milliontons of cattle and buffalo). The annual C emissions from fossil fuel combustion and cement production in South America represent only 2.5% (0.25 Pg C) of the total global emissions (9.8 Pg C). However, South America contributes 31.3% (0.34 Pg C) of global annual greenhouse gas emissions (1.1 Pg C) through Land Use and Land Use Change. The potential of South America as a terrestrial C sink for mitigating climate change with adoption of Low-Carbon Agriculture (LCA) strategies based on scenario analysis method is 8.24 Pg C between 2016 and 2050. The annual C offset for 2016 to 2020, 2021 to 2035, and 2036 to 2050 is estimated at 0.08, 0.25, and 0.28 Pg C, respectively, equivalent to offsetting 7.5, 22.2 and 25.2% of the global annual greenhouse gas emissions by Land Use and Land Use Change for each period. Emission offset for LCA activities is estimated at 31.0% by restoration of degraded pasturelands, 25.6% by integrated crop-livestock-forestry-systems, 24.3% by no-till cropping systems, 12.8% by planted commercial forest and forestation, 4.2% by biological N fixation and 2.0% by recycling the industrial organic wastes. The ecosystem carbon payback time for historical C losses from South America through LCA strategies may be 56 to 188years, and the adoption of LCA can also increase food and meat production by 615Mton or 17.6Mtonyear -1 and 56Mton or 1.6Mtonyear -1 , respectively, between 2016 and 2050. Copyright © 2016 Elsevier Ltd. All rights reserved.
Levoglucosan and phenols in Antarctic marine, coastal and plateau aerosols.
Zangrando, Roberta; Barbaro, Elena; Vecchiato, Marco; Kehrwald, Natalie M; Barbante, Carlo; Gambaro, Andrea
2016-02-15
Due to its isolated location, Antarctica is a natural laboratory for studying atmospheric aerosols and pollution in remote areas. Here, we determined levoglucosan and phenolic compounds (PCs) at diverse Antarctic sites: on the plateau, a coastal station and during an oceanographic cruise. Levoglucosan and PCs reached the Antarctic plateau where they were observed in accumulation mode aerosols (with median levoglucosan concentrations of 6.4 pg m(-3) and 4.1 pg m(-3), and median PC concentrations of 15.0 pg m(-3) and 7.3 pg m(-3)). Aged aerosols arrived at the coastal site through katabatic circulation with the majority of the levoglucosan mass distributed on larger particulates (24.8 pg m(-3)), while PCs were present in fine particles (34.0 pg m(-3)). The low levoglucosan/PC ratios in Antarctic aerosols suggest that biomass burning aerosols only had regional, rather than local, sources. General acid/aldehyde ratios were lower at the coastal site than on the plateau. Levoglucosan and PCs determined during the oceanographic cruise were 37.6 pg m(-3) and 58.5 pg m(-3) respectively. Unlike levoglucosan, which can only be produced by biomass burning, PCs have both biomass burning and other sources. Our comparisons of these two types of compounds across a range of Antarctic marine, coastal, and plateau sites demonstrate that local marine sources dominate Antarctic PC concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.
PG1258+593 and its common proper motion magnetic white dwarf counterpart
NASA Astrophysics Data System (ADS)
Girven, J.; Gänsicke, B. T.; Külebi, B.; Steeghs, D.; Jordan, S.; Marsh, T. R.; Koester, D.
2010-05-01
We confirm SDSSJ130033.48+590407.0 as a common proper motion companion to the well-studied hydrogen-atmosphere (DA) white dwarf PG1258+593 (GD322). The system lies at a distance of 68 +/- 3pc, where the angular separation of 16.1 +/- 0.1arcsec corresponds to a minimum binary separation of 1091 +/- 7au. SDSSJ1300+5904 is a cool (Teff = 6300 +/- 300K) magnetic white dwarf (B ~= 6mG). PG1258+593 is a DA white dwarf with Teff = 14790 +/- 77K and logg = 7.87 +/- 0.02. Using the white dwarf mass-radius relation implies the masses of SDSSJ1300+5904 and PG1258+593 are 0.54 +/- 0.06 and 0.54 +/- 0.01Msolar, respectively, and therefore a cooling age difference of 1.67 +/- 0.05Gyr. Adopting main-sequence lifetimes from stellar models, we derive an upper limit of 2.2Msolar for the mass of the progenitor of PG1258+593. A plausible range of initial masses is 1.4-1.8 Msolar for PG1258+593 and 2-3 Msolar for SDSSJ1300+5904. Our analysis shows that white dwarf common proper motion binaries can potentially constrain the white dwarf initial mass-final mass relation and the formation mechanism for magnetic white dwarfs. The magnetic field of SDSSJ1300+5904 is consistent with an Ap progenitor star. A common envelope origin of the system cannot be excluded, but requires a triple system as progenitor.
Pacora, Percy; Romero, Roberto; Chaiworapongsa, Tinnakorn; Kusanovic, Juan Pedro; Erez, Offer; Vaisbuch, Edi; Mazaki-Tovi1, Shali; Gotsch, Francesca; Kim, Chong Jai; Than, Nandor Gabor; Yeo, Lami; Mittal1, Pooja; Hassan, Sonia S.
2012-01-01
Objective Recent observations have revealed an interaction between inflammation and angiogenesis, which may be mediated by angiopoietins and chemokines. Given the importance of inflammation in parturition, we sought to determine whether angiopoietin-2 (Ang-2) is present in amniotic fluid (AF) and if its concentration changes with gestational age, labor, and in intra-amniotic infection/inflammation (IAI) in patients with spontaneous preterm labor and intact membranes. Study design This cross-sectional study included 486 patients in the following groups: 1) women in the midtrimester of pregnancy (14–18 weeks) who underwent amniocentesis for genetic indications and delivered a normal neonate at term (n=52); 2) normal pregnant women at term with (n=48) and without (n=45) spontaneous labor; 3) patients with an episode of spontaneous preterm labor (PTL) and intact membranes who were classified into: a) PTL without IAI who delivered at term (n=152); b) PTL without IAI who delivered preterm (<37 weeks gestation; n=107); and c) PTL with IAI (n=82). Ang-2 concentration in AF was determined by enzyme-linked immunoassay. Non-parametric statistics were used for analysis. Results 1) Ang-2 was detected in all AF samples; 2) the median AF Ang-2 concentration at term was significantly lower than that in the mid-trimester (1877.4 pg/mL vs. 3525.2 pg/mL; P<0.001); 3) among patients with PTL, the median AF Ang-2 concentration was significantly higher in patients with IAI than in those without IAI (4031.3 pg/mL vs. 2599.4 pg/mL; P<0.001) and those with PTL without IAI who delivered at term (4031.3 pg/mL vs. 2707.3 pg/mL; P<0.001); and 4) no significant differences were observed in the median AF Ang-2 concentration between patients with spontaneous labor at term and those at term not in labor (1722.9 pg/mL vs. 1877.4 pg/mL; P=0.6). Conclusions 1) Ang-2, a protein involved in the process of vascular remodeling, is a physiologic constituent of the amniotic fluid and its concentration decreased with advancing gestation; 2) the median Ang-2 concentration in amniotic fluid is higher in patients with IAI than in those without; and 3) spontaneous parturition at term is not associated with changes in the AF concentration of Ang-2. These findings support the view of a link between angiopoietins and inflammation. PMID:19435449
NASA Astrophysics Data System (ADS)
Arteaga, Lionel; Haëntjens, Nils; Boss, Emmanuel; Johnson, Kenneth S.; Sarmiento, Jorge L.
2018-04-01
Carbon export efficiency (e-ratio) is defined as the fraction of organic carbon fixed through net primary production (NPP) that is exported out of the surface productive layer of the ocean. Recent observations for the Southern Ocean suggest a negative e-ratio versus NPP relationship, and a reduced dependency of export efficiency on temperature, different than in the global domain. In this study, we complement information from a passive satellite sensor with novel space-based lidar observations of ocean particulate backscattering to infer NPP over the entire annual cycle, and estimate Southern Ocean export rates from five different empirical models of export efficiency. Inferred Southern Ocean NPP falls within the range of previous studies, with a mean estimate of 15.8 (± 3.9) Pg C yr-1 for the region south of 30°S during the 2005-2016 period. We find that an export efficiency model that accounts for silica(Si)-ballasting, which is constrained by observations with a negative e-ratio versus NPP relationship, shows the best agreement with in situ-based estimates of annual net community production (annual export of 2.7 ± 0.6 Pg C yr-1 south of 30°S). By contrast, models based on the analysis of global observations with a positive e-ratio versus NPP relationship predict annually integrated export rates that are ˜ 33% higher than the Si-dependent model. Our results suggest that accounting for Si-induced ballasting is important for the estimation of carbon export in the Southern Ocean.
Lundquist, Peter K.; Poliakov, Anton; Bhuiyan, Nazmul H.; Zybailov, Boris; Sun, Qi; van Wijk, Klaas J.
2012-01-01
Plastoglobules (PGs) in chloroplasts are thylakoid-associated monolayer lipoprotein particles containing prenyl and neutral lipids and several dozen proteins mostly with unknown functions. An integrated view of the role of the PG is lacking. Here, we better define the PG proteome and provide a conceptual framework for further studies. The PG proteome from Arabidopsis (Arabidopsis thaliana) leaf chloroplasts was determined by mass spectrometry of isolated PGs and quantitative comparison with the proteomes of unfractionated leaves, thylakoids, and stroma. Scanning electron microscopy showed the purity and size distribution of the isolated PGs. Compared with previous PG proteome analyses, we excluded several proteins and identified six new PG proteins, including an M48 metallopeptidase and two Absence of bc1 complex (ABC1) atypical kinases, confirmed by immunoblotting. This refined PG proteome consisted of 30 proteins, including six ABC1 kinases and seven fibrillins together comprising more than 70% of the PG protein mass. Other fibrillins were located predominantly in the stroma or thylakoid and not in PGs; we discovered that this partitioning can be predicted by their isoelectric point and hydrophobicity. A genome-wide coexpression network for the PG genes was then constructed from mRNA expression data. This revealed a modular network with four distinct modules that each contained at least one ABC1K and/or fibrillin gene. Each module showed clear enrichment in specific functions, including chlorophyll degradation/senescence, isoprenoid biosynthesis, plastid proteolysis, and redox regulators and phosphoregulators of electron flow. We propose a new testable model for the PGs, in which sets of genes are associated with specific PG functions. PMID:22274653
Bansal, Harkirat S; Takhar, Pawan S; Alvarado, Christine Z; Thompson, Leslie D
2015-12-01
Hybrid mixture theory (HMT) based 2-scale fluid transport relations of Takhar coupled with a multiphase heat transfer equation were solved to model water, oil and gas movement during frying of chicken nuggets. A chicken nugget was treated as a heterogeneous material consisting of meat core with wheat-based coating. The coupled heat and fluid transfer equations were solved using the finite element method. Numerical simulations resulted in data on spatial and temporal profiles for moisture, rate of evaporation, temperature, oil, pore pressure, pressure in various phases, and coefficient of elasticity. Results showed that most of the oil stayed in the outer 1.5 mm of the coating region. Temperature values greater than 100 °C were observed in the coating after 30 s of frying. Negative gage-pore pressure (p(w) < p(g)) magnitudes were observed in simulations, which is in agreement with experimental observations of Sandhu and others. It is hypothesized that high water-phase capillary pressure (p(c) > p(g)) in the hydrophilic matrix causes p(w) < p(g), which further results in negative pore pressure. The coefficient of elasticity was the highest at the surface (2.5 × 10(5) Pa) for coating and the interface of coating and core (6 × 10(5) Pa). Kinetics equation for color change obtained from experiments was coupled with the HMT based model to predict the color (L, a, and b) as a function of frying time. © 2015 Institute of Food Technologists®
The distribution of Abbott high-sensitivity troponin I levels in Korean patients with chest pain.
Lee, Kyunghoon; Lee, Soo-Youn; Choi, Jin-Oh; Jeon, Eun-Seok; Park, Hyung-Doo
2015-01-01
Troponin is considered a primary biomarker for coronary heart disease. We investigated the clinical utility of the Abbott high-sensitivity cardiac troponin I (hs-TnI) assay in patients with various cardiac problems. Precision was investigated by ten levels of pooled sera and three levels of control materials. We determined Abbott hs-TnI levels in a total of 3314 Korean patients with chest pain, including acute myocardial infarction (n=381), unstable angina (n=327), stable angina (n=1361), variant angina (n=189), non-coronary artery diseases (n=236), and nonspecific chest pain (n=820). The 99(th) percentile cutoff was established by the plasma from the cardio-healthy subgroup and validated by 118 healthy individuals. The total coefficient of variation in patient pooled sera and controls ranged from 3.93-6.35% and 4.81-9.73%, respectively. There was a significant difference in hs-TnI among various cardiac problems: subjects with non-cardiac chest pain (median 1.7 pg/mL, 25%/75% quartile 1.1/2.8 pg/mL), variant angina (2.4 pg/mL,1.4/5.6 pg/mL), stable angina (3.7 pg/mL, 2.1/8.9 pg/mL), unstable angina (10.7 pg/mL, 3.7/61.7 pg/mL), and non-coronary artery diseases (9.3 pg/mL, 4.3/37.4 pg/mL). However, the median levels of hs-TnI were not statistically different (p=0.921) between unstable angina and non-coronary artery diseases. The overall 99(th) percentile cutoff was 19.3 pg/mL (range 0.2-30.6 pg/mL). This new hs-TnI assay may be helpful in determining a differential diagnosis in patients with chest pain. © 2015 by the Association of Clinical Scientists, Inc.
Nomura, Tsutomu; Ushio, Munetaka; Kondo, Kenji; Kikuchi, Shigeru
2018-10-01
The purpose of this research is to examine the changes in nasal airflow dynamics before and after the nasal perforation repair. Three dimensional (3D) models of the nasal cavity before and after septal perforation repair was reconstructed using preoperative and postoperative computed tomography (CT) images of a patient. The numerical simulation was carried out using ANSYS CFX V15.0. Pre- and post-operative models were compared by their velocity, pressure (P), pressure gradient (PG), wall shear (WS), shear strain rate (SSR) and turbulence kinetic energy (TKE) in three plains. In the post-operative state, the cross flows disappeared. In preoperative state, there were areas showing high PG, WS, SSR at the posterior border of the perforation, which exactly correspond to the area showing erosive mucosa on endoscopic inspection of the patient. In postoperative state, such high PG, WS and SSR areas disappeared. High TKEs also disappeared after surgery. The effects of septal perforation repair on airflow dynamics were evaluated using computer fluid dynamics (CFD). High WS, PG and SSR observed at the edge of the septal perforation may be related to the clinical symptom such as nasal bleeding and pain. TKE was considered to cause nasal symptom. Copyright © 2018 Elsevier B.V. All rights reserved.
Vijayaraghavan, Jagamya; Kumar, Vijay; Krishnan, Nikhil P; Kaufhold, Ross T; Zeng, Ximin; Lin, Jun; van den Akker, Focco
2018-01-01
The bacterial soluble lytic transglycosylase (LT) breaks down the peptidoglycan (PG) layer during processes such as cell division. We present here crystal structures of the soluble LT Cj0843 from Campylobacter jejuni with and without bulgecin A inhibitor in the active site. Cj0843 has a doughnut shape similar but not identical to that of E. coli SLT70. The C-terminal catalytic domain is preceded by an L-domain, a large helical U-domain, a flexible linker, and a small N-terminal NU-domain. The flexible linker allows the NU-domain to reach over and complete the circular shape, using residues conserved in the Epsilonproteobacteria LT family. The inner surface of the Cj0843 doughnut is mostly positively charged including a pocket that has 8 Arg/Lys residues. Molecular dynamics simulations with PG strands revealed a potential functional role for this pocket in anchoring the negatively charged terminal tetrapeptide of the PG during several steps in the reaction including homing and aligning the PG strand for exolytic cleavage, and subsequent ratcheting of the PG strand to enhance processivity in degrading PG strands.
Influence of Motion Picture Rating on Adolescent Response to Movie Smoking
Tanski, Susanne; Stoolmiller, Mike
2012-01-01
OBJECTIVE: To examine the association between movie smoking exposure (MSE) and adolescent smoking according to rating category. METHODS: A total of 6522 US adolescents were enrolled in a longitudinal survey conducted at 8-month intervals; 5503 subjects were followed up at 8 months, 5019 subjects at 16 months, and 4575 subjects at 24 months. MSE was estimated from 532 recent box-office hits, blocked into 3 Motion Picture Association of America rating categories: G/PG, PG-13, and R. A survival model evaluated time to smoking onset. RESULTS: Median MSE in PG-13–rated movies was ∼3 times higher than median MSE from R-rated movies, but their relation with smoking was essentially the same, with adjusted hazard ratios of 1.49 (95% confidence interval [CI]: 1.23–1.81) and 1.33 (95% CI: 1.23–1.81) for each additional 500 occurrences of MSE respectively. MSE from G/PG-rated movies was small and had no significant relationship with adolescent smoking. Attributable risk estimates showed that adolescent smoking would be reduced by 18% (95% CI: 14–21) if smoking in PG-13–rated movies was reduced to the fifth percentile. In comparison, making all parents maximally authoritative in their parenting would reduce adolescent smoking by 16% (95% CI: 12–19). CONCLUSIONS: The equivalent effect of PG-13-rated and R-rated MSE suggests it is the movie smoking that prompts adolescents to smoke, not other characteristics of R-rated movies or adolescents drawn to them. An R rating for movie smoking could substantially reduce adolescent smoking by eliminating smoking from PG-13 movies. PMID:22778305
Paddock, Ethan; Hohenadel, Maximilian G; Piaggi, Paolo; Vijayakumar, Pavithra; Hanson, Robert L; Knowler, William C; Krakoff, Jonathan; Chang, Douglas C
2017-09-01
Elevated 2-h plasma glucose concentration (2 h-PG) during a 75 g OGTT predict the development of type 2 diabetes mellitus. However, 1-h plasma glucose concentration (1 h-PG) is associated with insulin secretion and may be a better predictor of type 2 diabetes. We aimed to investigate the association between 1 h-PG and 2 h-PG using gold standard methods for measuring insulin secretion and action. We also compared 1 h-PG and 2 h-PG as predictors of type 2 diabetes mellitus. This analysis included adult volunteers without diabetes, predominantly Native Americans of Southwestern heritage, who were involved in a longitudinal epidemiological study from 1965 to 2007, with a baseline OGTT that included measurement of 1 h-PG. Group 1 (n = 716) underwent an IVGTT and hyperinsulinaemic-euglycaemic clamp for measurement of acute insulin response (AIR) and insulin-stimulated glucose disposal (M), respectively. Some members of Group 1 (n = 490 of 716) and members of a second, larger, group (Group 2; n = 1946) were followed-up to assess the development of type 2 diabetes (median 9.0 and 12.8 years follow-up, respectively). Compared with 2 h-PG (r = -0.281), 1 h-PG (r = -0.384) was more closely associated with AIR, whereas, compared with 1 h-PG (r = -0.340), 2 h-PG (r = -0.408) was more closely associated with M. Measures of 1 h-PG and 2 h-PG had similar abilities to predict type 2 diabetes, which did not change when both were included in the model. A 1 h-PG cut-off of 9.3 mmol/l provided similar levels of sensitivity and specificity as a 2 h-PG cut-off of 7.8 mmol/l; the latter is used to define impaired glucose tolerance, a recognised predictor of type 2 diabetes mellitus. The 1 h-PG was associated with important physiological predictors of type 2 diabetes and was as effective as 2 h-PG for predicting type 2 diabetes mellitus. The 1 h-PG is, therefore, an alternative method of identifying individuals with an elevated risk of type 2 diabetes mellitus.
He, Fupo; Zhang, Jing; Yang, Fanwen; Zhu, Jixiang; Tian, Xiumei; Chen, Xiaoming
2015-05-01
The robust calcium carbonate composite ceramics (CC/PG) can be acquired by fast sintering calcium carbonate at a low temperature (650 °C) using a biocompatible, degradable phosphate-based glass (PG) as sintering agent. In the present study, the in vitro degradation and cell response of CC/PG were assessed and compared with 4 synthetic bone substitute materials, calcium carbonate ceramic (CC), PG, hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) ceramics. The degradation rates in decreasing order were as follows: PG, CC, CC/PG, β-TCP, and HA. The proliferation of rat bone mesenchymal stem cells (rMSCs) cultured on the CC/PG was comparable with that on CC and PG, but inferior to HA and β-TCP. The alkaline phosphatase (ALP) activity of rMSCs on CC/PG was lower than PG, comparable with β-TCP, but higher than HA. The rMSCs on CC/PG and PG had enhanced gene expression in specific osteogenic markers, respectively. Compared to HA and β-TCP, the rMSCs on the CC/PG expressed relatively lower level of collagen I and runt-related transcription factor 2, but showed more considerable expression of osteopontin. Although CC, PG, HA, and β-TCP possessed impressive performances in some specific aspects, they faced extant intrinsic drawbacks in either degradation rate or mechanical strength. Based on considerable compressive strength, moderate degradation rate, good cell response, and being free of obvious shortcoming, the CC/PG is promising as another choice for bone substitute materials. Copyright © 2015 Elsevier B.V. All rights reserved.
Prediction in processing is a by-product of language learning.
Chang, Franklin; Kidd, Evan; Rowland, Caroline F
2013-08-01
Both children and adults predict the content of upcoming language, suggesting that prediction is useful for learning as well as processing. We present an alternative model which can explain prediction behaviour as a by-product of language learning. We suggest that a consideration of language acquisition places important constraints on Pickering & Garrod's (P&G's) theory.
Terefe, Netsanet Shiferaw; Buckow, Roman; Versteeg, Cornelis
2015-01-01
High-power ultrasound is a versatile technology which can potentially be used in many food processing applications including food preservation. This is part 2 of a series of review articles dealing with the effectiveness of nonthermal food processing technologies in food preservation focusing on their effect on enzymes. Typically, ultrasound treatment alone does not efficiently cause microbial or enzyme inactivation sufficient for food preservation. However, combined with mild heat with or without elevated pressure (P ≤ 500 kPa), ultrasound can effectively inactivate enzymes and microorganisms. Synergistic effects between ultrasound and mild heat have been reported for the inactivation of both enzymes and microorganisms. The application of ultrasound has been shown to enhance the rate of inactivation of quality degrading enzymes including pectin methylesterase (PME), polygalacturonase (PG), peroxidase (POD), polyphenol oxidase (PPO), and lipoxygenase (LOX) at mild temperature by up to 400 times. Moreover, ultrasound enables the inactivation of relatively heat-resistant enzymes such as tomato PG1 and thermostable orange PME at mild temperature conditions. The extent to which ultrasound enhances the inactivation rate depends on the type of enzyme, the medium in which the enzyme is suspended, and the processing condition including frequency, ultrasonic intensity, temperature, and pressure. The physical and chemical effects of cavitation are considered to be responsible for the ultrasound-induced inactivation of enzymes, although the dominant mechanism depends on the structure of the enzyme.
NASA Astrophysics Data System (ADS)
Hember, R. A.; Kurz, W. A.; Coops, N. C.; Black, T. A.
2010-12-01
Temperate-maritime forests of coastal British Columbia store large amounts of carbon (C) in soil, detritus, and trees. To better understand the sensitivity of these C stocks to climate variability, simulations were conducted using a hybrid version of the model, Physiological Principles Predicting Growth (3-PG), combined with algorithms from the Carbon Budget Model of the Canadian Forest Sector - version 3 (CBM-CFS3) to account for full ecosystem C dynamics. The model was optimized based on a combination of monthly CO2 and H2O flux measurements derived from three eddy-covariance systems and multi-annual stemwood growth (Gsw) and mortality (Msw) derived from 1300 permanent sample plots by means of Markov chain Monte Carlo sampling. The calibrated model serves as an unbiased estimator of stemwood C with enhanced precision over that of strictly-empirical models, minimized reliance on local prescriptions, and the flexibility to study impacts of environmental change on regional C stocks. We report the contribution of each dataset in identifying key physiological parameters and the posterior uncertainty in predictions of net ecosystem production (NEP). The calibrated model was used to spin up pre-industrial C pools and estimate the sensitivity of regional net carbon balance to a gradient of temperature changes, λ=ΔC/ΔT, during three 62-year harvest rotations, spanning 1949-2135. Simulations suggest that regional net primary production, tree mortality, and heterotrophic respiration all began increasing, while NEP began decreasing in response to warming following the 1976 shift in northeast-Pacific climate. We quantified the uncertainty of λ and how it was mediated by initial dead C, tree mortality, precipitation change, and the time horizon in which it was calculated.
Iowa Gambling Task (IGT): twenty years after – gambling disorder and IGT
Brevers, Damien; Bechara, Antoine; Cleeremans, Axel; Noël, Xavier
2013-01-01
The Iowa Gambling Task (IGT) involves probabilistic learning via monetary rewards and punishments, where advantageous task performance requires subjects to forego potential large immediate rewards for small longer-term rewards to avoid larger losses. Pathological gamblers (PG) perform worse on the IGT compared to controls, relating to their persistent preference toward high, immediate, and uncertain rewards despite experiencing larger losses. In this contribution, we review studies that investigated processes associated with poor IGT performance in PG. Findings from these studies seem to fit with recent neurocognitive models of addiction, which argue that the diminished ability of addicted individuals to ponder short-term against long-term consequences of a choice may be the product of an hyperactive automatic attentional and memory system for signaling the presence of addiction-related cues (e.g., high uncertain rewards associated with disadvantageous decks selection during the IGT) and for attributing to such cues pleasure and excitement. This incentive-salience associated with gambling-related choice in PG may be so high that it could literally “hijack” resources [“hot” executive functions (EFs)] involved in emotional self-regulation and necessary to allow the enactment of further elaborate decontextualized problem-solving abilities (“cool” EFs). A framework for future research is also proposed, which highlights the need for studies examining how these processes contribute specifically to the aberrant choice profile displayed by PG on the IGT. PMID:24137138
Gunjaca, Ivan; Zunic, Josip; Gunjaca, Mihaela; Kovac, Zdenko
2012-04-01
The aim of our study was to evaluate the pro- and anti-inflammatory cytokine response during acute pancreatitis and its predictive value on severity of disease. A hospital-based prospective clinical study was conducted. Twenty patients with acute pancreatitis were enrolled during a 12-month period. Plasma concentrations of TNF-α, IL-1β, IL-6, and IL-10 were determined at days 1, 2, 3, 6, and 9. The patient population was analyzed by type of acute pancreatitis. Severity was defined according to the Atlanta criteria for assessing severity of acute pancreatitis. Clinical variables were recorded to patients classified in one of two groups: severe acute pancreatitis (SAP group) and mild acute pancreatitis (MILD group). Patients with SAP had significantly higher average levels of IL-6 compared to the MILD group patients (539.2 pg/L vs. 23.4 pg/L, p < 0.0001). Also, the values of IL-10 were significantly higher in patients with SAP (242.4 pg/L vs. 8.1 pg/L, p = 0.003). The values of TNF-α were not significantly different in both groups. The value of IL-6 and IL-10 showed a positive correlation (r = 0.7964, p < 0.0001). Although a relatively small sample of patients was used, we can conclude that the determination of the value of IL-6 and IL-10 can help in the clinical assessment of disease severity.
McArt, J A A; Nydam, D V; Ospina, P A; Oetzel, G R
2011-12-01
The purpose of this study was to determine the effect of oral propylene glycol (PG) administration on ketosis resolution and milk yield in cows diagnosed with subclinical ketosis (SCK). Cows from 4 freestall dairy herds (2 in New York and 2 in Wisconsin) were each tested 6 times for SCK from 3 to 16 d in milk on Mondays, Wednesdays, and Fridays. Subclinical ketosis was defined as a β-hydroxybutyrate (BHBA) concentration of 1.2 to 2.9 mmol/L, [corrected] and clinical ketosis was defined as ≥ 3.0 mmol/L. [corrected]. Cows with SCK were randomized to the treatment group (oral PG) or control group (no PG); treatment cows were drenched with 300 mL of PG once daily from the day they tested 1.2 to 2.9 mmol/L [corrected] until the day they tested <1.2 mmol/L. [corrected]. Outcomes evaluated for all farms included time from SCK until BHBA test <1.2 mmol/L [corrected] or until BHBA test ≥ 3.0 mmol/L. [corrected]. Individual milk weights for the first 30 d of lactation were evaluated for the 3 farms monitoring daily milk. Semiparametric proportional hazards models were used to evaluate time to event outcomes; repeated-measures ANOVA was used to assess milk weights. A total of 741 of 1,717 (43.2%) eligible enrolled cows had at least one BHBA test of 1.2 to 2.9 mmol/L. [corrected]. Of these, 372 were assigned to the treatment group and 369 to the control group. Based on hazard ratios, PG-treated cows were 1.50 times more likely (95% confidence interval=1.26 to 1.79) to resolve their SCK and 0.54 times less likely (95% confidence interval=0.34 to 0.86) to develop clinical ketosis than control cows. Across the 3 herds measuring individual milk weights, treated cows produced 0.23 kg more milk per milking in the first 30 d of lactation than control cows, for a total difference of 0.69 kg/cow per day. After identification of a treatment by herd interaction, stratification by herd showed that treated cows produced more milk per milking on farm A (0.44 kg) and farm B (0.53 kg) in the first 30 d of lactation than control cows, for a total difference of 1.34 and 1.59 kg/d, respectively; milk production did not differ (0.02 kg per milking) between the 2 groups on farm D. These results show the positive effects of oral PG administration in fresh cows with SCK by helping to resolve SCK and preventing clinical ketosis. In addition, oral PG improves milk yield during early lactation in cows diagnosed with SCK. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Binding study of lysozyme with Al(III) using chemiluminescence analysis.
Liu, Jiangman; Luo, Kai; Song, Zhenghua
2014-09-01
The binding behavior of lysozyme with Al(III) is described using luminol as a luminescence probe by flow injection-chemiluminescence (FI-CL) analysis. It was found that the CL intensity of the luminol-lysozyme reaction could be markedly enhanced by Al(III), and the increase in CL intensity was linear with the Al(III) concentration over the range 0.3-30.0 pg mL(-1) , with a detection limit of 0.1 pg mL(-1) (3σ). Based on the interaction model of lysozyme with Al(III), lg[(I - I0 )/(2I0 - I)] = lgK + nlg[M], the binding constant K = 6.84 × 10(6) L mol(-1) and the number of binding sites (n) = 0.76. The relative standard deviations were 3.2, 2.4 and 2.0% for 10.0, 20.0 and 30.0 pg mL(-1) Al(III) (n = 7), respectively. This new method was successfully applied to continuous, quantitative monitoring of picogram level Al(III) in human saliva following oral intake of compound aluminum hydroxide tablets. It was found that Al(III) in saliva reached a maximum of 101.2 ng mL(-1) at 3.0 h. The absorption rate constant ka , elimination rate constant k and half-life time t1/2 of Al(III) were 1.378 h(-1) , 0.264 h(-1) and 2.624 h, respectively. Copyright © 2013 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ito, Gen; Kobayashi, Takeshi; Takeda, Yoshie
Highlights: • Proteoglycan from salmon nasal cartridge (SNC-PG) promoted wound healing in fibroblast monolayers. • SNC-PG stimulated both cell proliferation and cell migration. • Interaction between chondroitin sulfate-units and CD44 is responsible for the effect. - Abstract: Proteoglycans (PGs) are involved in various cellular functions including cell growth, adhesion, and differentiation; however, their physiological roles are not fully understood. In this study, we examined the effect of PG purified from salmon nasal cartilage (SNC-PG) on wound closure using tissue-cultured cell monolayers, an in vitro wound-healing assay. The results indicated that SNC-PG significantly promoted wound closure in NIH/3T3 cell monolayers bymore » stimulating both cell proliferation and cell migration. SNC-PG was effective in concentrations from 0.1 to 10 μg/ml, but showed much less effect at higher concentrations (100–1000 μg/ml). The effect of SNC-PG was abolished by chondroitinase ABC, indicating that chondroitin sulfates (CSs), a major component of glycosaminoglycans (GAGs) in SNC-PG, are crucial for the SNC-PG effect. Furthermore, chondroitin 6-sulfate (C-6-S), a major CS of SNC-PG GAGs, could partially reproduce the SNC-PG effect and partially inhibit the binding of SNC-PG to cells, suggesting that SNC-PG exerts its effect through an interaction between the GAGs in SNC-PG and the cell surface. Neutralization by anti-CD44 antibodies or CD44 knockdown abolished SNC-PG binding to the cells and the SNC-PG effect on wound closure. These results suggest that interactions between CS-rich GAG-chains of SNC-PG and CD44 on the cell surface are responsible for the SNC-PG effect on wound closure.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burdick, Michael J.; Reddy, Chandana A.; Ulchaker, James
2009-04-01
Purpose: To determine whether the primary grade (PG) of biopsy Gleason score (GS) 7 prostate cancer (CaP) was predictive for biochemical relapse-free survival (bRFS). Most of the present data regarding the PG of GS7 CaP refer to surgical specimens. Our goal was to determine whether the biopsy GS used at the time of medical decision making predicted for the biochemical outcome. Methods and Materials: We reviewed the data from 705 patients with biopsy GS7 CaP, from a prospectively maintained database, who had been treated at our institution between September 1996 and March 2005 with radical prostatectomy (n = 310), externalmore » beam radiotherapy (n = 268), or prostate radioactive seed implantation (n = 127). The bRFS rates were estimated using the Kaplan-Meier method. Cox proportional hazards regression analysis was used for univariate and multivariate analyses examining these factors in relation to bRFS: PG of biopsy GS, initial prostate-specific antigen level, clinical T stage, use of androgen deprivation, risk group (high or intermediate), and treatment modality. Results: The 5-year bRFS rate was 78% and 71% (p = 0.0108) for biopsy GS7 PG3 CaP and biopsy GS7 PG4 CaP, respectively. Comparing PG3 and PG4 within treatment modalities, only prostate implantation patients had a significant difference in the 5-year bRFS rate, 88% vs. 76%, respectively (p = 0.0231). On multivariate analysis, the PG of biopsy GS remained an independent predictor of bRFS, with PG3 having better bRFS than PG4 (relative risk, 0.655; 95% confidence interval, 0.472-0.909; p = 0.0113). Conclusion: Biopsy GS7 PG4 CaP carries a worse bRFS than biopsy GS7 PG3 CaP.« less
Labetoulle, Marc; Messmer, Elisabeth M; Pisella, Pierre-Jean; Ogundele, Abayomi; Baudouin, Christophe
2017-04-01
To demonstrate non-inferiority of a hydroxypropyl guar/polyethylene glycol/propylene glycol lubricating eye-drop (HPG/PEG/PG) compared with an osmoprotective carboxymethylcellulose/glycerine eye-drop (O/CMC) for ocular surface staining. This was a multicentre, randomised, observer-masked, parallel-group study. Adults with dry eye instilled HPG/PEG/PG/ or O/CMC 4 times daily for 35 days and then as needed through day 90. Total ocular surface staining (TOSS) score changes from baseline and Impact of Dry Eye on Everyday Life (IDEEL) treatment satisfaction module scores were assessed. Non-inferiority, based on TOSS score change from baseline, was concluded if the upper limit of the 2-sided CI was <2 units. Mean±SD patient age was 64.4±13.7 years; 94 patients were randomised to treatment (HPG/PEG/PG, n=46; O/CMC, n=48). Mean±SE TOSS score change from baseline to day 35 was -2.2±0.33 with HPG/PEG/PG and -1.7±0.47 with O/CMC (treatment difference, -0.47±0.47; p=0.38), and the non-inferiority criterion was met. IDEEL treatment satisfaction scores were similar between groups at day 35 and day 90. The most frequently reported adverse event was eye irritation (HPG/PEG/PG, n=2; O/CMC, n=3). HPG/PEG/PG and O/CMC reduced ocular surface damage, and HPG/PEG/PG was non-inferior to O/CMC. Both treatments were effective, convenient and well tolerated. NCT01863368, Results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Constraining estimates of global soil respiration by quantifying sources of variability.
Jian, Jinshi; Steele, Meredith K; Thomas, R Quinn; Day, Susan D; Hodges, Steven C
2018-05-10
Quantifying global soil respiration (R SG ) and its response to temperature change are critical for predicting the turnover of terrestrial carbon stocks and their feedbacks to climate change. Currently, estimates of R SG range from 68 to 98 Pg C year -1 , causing considerable uncertainty in the global carbon budget. We argue the source of this variability lies in the upscaling assumptions regarding the model format, data timescales, and precipitation component. To quantify the variability and constrain R SG , we developed R SG models using Random Forest and exponential models, and used different timescales (daily, monthly, and annual) of soil respiration (R S ) and climate data to predict R SG . From the resulting R SG estimates (range = 66.62-100.72 Pg), we calculated variability associated with each assumption. Among model formats, using monthly R S data rather than annual data decreased R SG by 7.43-9.46 Pg; however, R SG calculated from daily R S data was only 1.83 Pg lower than the R SG from monthly data. Using mean annual precipitation and temperature data instead of monthly data caused +4.84 and -4.36 Pg C differences, respectively. If the timescale of R S data is constant, R SG estimated by the first-order exponential (93.2 Pg) was greater than the Random Forest (78.76 Pg) or second-order exponential (76.18 Pg) estimates. These results highlight the importance of variation at subannual timescales for upscaling to R SG . The results indicated R SG is lower than in recent papers and the current benchmark for land models (98 Pg C year -1 ), and thus may change the predicted rates of terrestrial carbon turnover and the carbon to climate feedback as global temperatures rise. © 2018 John Wiley & Sons Ltd.
Liu, Jian; Bo, Xiangjie; Zhao, Zheng; Guo, Liping
2015-12-15
In this study, we developed a novel biosensor based on highly exposed Pt nanoparticles (Pt NPs) decorated porous graphene (PG) for the reliable detection of extracellular hydrogen peroxide (H2O2) released from living cells. The commercially available low-cost hydrophilic CaCO3 spheres were used as template for preparing PG. The porous structure provided larger surface area and more active sites. Due to the porous structure of PG, the Pt NPs supported on PG were not secluded by aggregated graphene layers and were highly exposed to target molecules. Ultrafine Pt NPs were well dispersed and loaded on PG by a method of microwave assistance. Electrochemical performances of the Pt/PG nanocomposites modified glassy carbon electrode (GCE) were investigated. The electrocatalytic reduction of H2O2 showed a wide linear range from 1 to 1477 μM, with a high sensitivity of 341.14 μA mM(-1) cm(-2) and a limit of detection (LOD) as low as 0.50 μM. Moreover, the Pt/PG/GCE exhibited excellent anti-interference property, reproducibility and long-term storage stability. Because of these remarkable analytical advantages, the constructed sensor was used to determine H2O2 released from living cells with satisfactory results. The superior catalytic activity makes Pt/PG nanocomposites a promising candidate for electrochemical sensors and biosensors design. Copyright © 2015 Elsevier B.V. All rights reserved.
Rayne, Sierra; Ikonomou, Michael G; Butt, Craig M; Diamond, Miriam L; Truong, Jennifer
2005-04-01
Samples of ambient organic films deposited on exterior window surfaces from lower Manhattan and Brooklyn in New York City were collected six weeks after the terrorist attacks at the World Trade Center (WTC) on September 11, 2001 and analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Total tetra- through octa-CDD/F concentrations in window films within 1 km of the WTC site in lower Manhattan ranged up to 630,000 pg/m2 (estimated as a mass concentration of ca. 1,300,000 pg/ g) and a maximum toxic equivalent (TEQ) concentration of 4700 TEQ/m2 (ca. 10 000 pg TEQ/g). Measurements at a background site 3.5 km away in Brooklyn showed lower concentrations at 130 pg TEQ/m2 (260 pg TEQ/g). Ambient gas-phase PCDD/F concentrations estimated for each site using an equilibrium partitioning model suggested concentrations ranging from ca. 2700 fg-TEQ/m3 near the WTC site to the more typical urban concentration of 20 fg-TEQ/m3 atthe Brooklyn site. Multivariate analyses of 2,3,7,8-substitued congeners and homologue group profiles suggested unique patterns in films near the WTC site compared to that observed at background sites in the study area and in other literature-derived combustion source profiles. Homologue profiles near the WTC site were dominated by tetra-, penta-, and Hexa-CDD/Fs, and 2,3,7,8-substituted profiles contained mostly octa- and hexachlorinated congeners. In comparison, profiles in Brooklyn and near mid-Manhattan exhibited congener and homologue patterns comprised mainly of hepta- and octa-CDDs, similar to that commonly reported in background air and soil.
Molnár, Borbála; Fodor, Blanka; Boldizsár, Imre; Molnár-Perl, Ibolya
2016-04-01
A literature criticism is given on methods using currently gas chromatography mass spectrometry (GC/MS) to determine cathine (CAT), cathinone (CTN) and norephedrine (NE), jointly khatamines. In this study, khatamines' oximation, trimethylsilylation and mass fragmentation properties-applying N-Methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA), its trimethyliodosilane (TMIS) catalyst containing version (MSTFA(TMIS)), N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) and hexamethyldisilazane (HMDS)-was highlighted, at first. Derivatization, mass fragmentation and quantitation related, optimized model investigations have been carried out as a function of the reaction times and conditions. Special emphasis was put (i) on the stability of the primarily formed (CAT-2TMS, NE-2TMS, CTN-TMS(TMS-oximes)1,2), then transformed, fully derived (CAT-3TMS, NE-3MTS, CTN-2TMS(TMS-oximes)1,2) species, and, (ii) on the proportionally formed stable products, suitable to selective quantitation of all three natural amines, simultaneously. Results, as novelty to the field confirmed that (i) TMIS catalyzed trimethylsilyation triggers to form fully derivatized species unfortunately, in part only; while, (ii) khatamines' simultaneous quantitation needs to be carried out in a two steps derivatization process consisting of oximation (1st step, hydroxylamine in pyridine) and trimethylsilylation (2nd step, MSTFA), to the CAT-2TMS, NE-2TMS, CTN-TMS(TMS-oximes)1,2. These species were characterized with their retention, mass fragmentation and analytical performance properties, in model solutions and in the presence of plant tissues, as well: R(2), limit of quantitation (LOQ) data, expressed in pg/1μL injection basis, proved to be 62.5pg (CAT), 20pg (NE) and 62.5pg (CTN), respectively. The practical utility of proposal was enormously enhanced by the novel, direct sample preparation method. In this process, the freshly harvested, freeze-dried, then pulverized leaves of Catha edulis FORKS were directly derivatized, in the presence of the matrix. Reproducibility (in average 2.07 RSD% varying between 0.15 and 5.5 RSD%), linearity (0.9990-0.9994) and recovery (95.7-99.1%) values of the new sample preparation protocol was confirmed by the standard addition method for CAT, NE and CTN equally. From plant leaf, 0.061w/w% CAT and 0.014w/w% NE contents were obtained. In this tissue CTN was not found. Very likely attributable to the unfavorable climate for the plant: grown in Hungary of temperate zone and naturalized in the tropical Africa. Copyright © 2016 Elsevier B.V. All rights reserved.
Two types of nanoparticle-based bio-barcode amplification assays to detect HIV-1 p24 antigen.
Dong, Huahuang; Liu, Jianli; Zhu, Hong; Ou, Chin-Yih; Xing, Wenge; Qiu, Maofeng; Zhang, Guiyun; Xiao, Yao; Yao, Jun; Pan, Pinliang; Jiang, Yan
2012-08-31
HIV-1 p24 antigen is a major viral component of human immunodeficiency virus type 1 (HIV-1) which can be used to identify persons in the early stage of infection and transmission of HIV-1 from infected mothers to infants. The detection of p24 is usually accomplished by using an enzyme-linked immunosorbent assay (ELISA) with low detection sensitivity. Here we report the use of two bio-barcode amplification (BCA) assays combined with polymerase chain reaction (PCR) and gel electrophoresis to quantify HIV-1 p24 antigen. A pair of anti-p24 monoclonal antibodies (mAbs) were used in BCA assays to capture HIV-1 p24 antigen in a sandwich format and allowed for the quantitative measurement of captured p24 using PCR and gel electrophoresis. The first 1 G12 mAb was coated on microplate wells or magnetic microparticles (MMPs) to capture free p24 antigens. Captured p24 in turn captured 1D4 mAb coated gold nanoparticle probes (GNPs) containing double-stranded DNA oligonucleotides. One strand of the oligonucleotides was covalently immobilized whereas the unbound complimentary bio-barcode DNA strand could be released upon heating. The released bio-barcode DNA was amplified by PCR, electrophoresed in agarose gel and quantified. The in-house ELISA assay was found to quantify p24 antigen with a limit of detection (LOD) of 1,000 pg/ml and a linear range between 3,000 and 100,000 pg/ml. In contrast, the BCA-based microplate method yielded an LOD of 1 pg/ml and a linear detection range from 1 to 10,000 pg/ml. The BCA-based MMP method yielded an LOD of 0.1 pg/ml and a linear detection range from 0.1 to 1,000 pg/ml. When combined with PCR and simple gel electrophoresis, BCA-based microplate and MMPs assays can be used to quantify HIV-1 p24 antigen. These methods are 3-4 orders of magnitude more sensitive than our in-house ELISA-based assay and may provide a useful approach to detect p24 in patients newly infected with HIV.
Baseline serum CXCL10 and IL-12 levels may predict severe asthmatics' responsiveness to omalizumab.
Suzukawa, Maho; Matsumoto, Hisako; Ohshima, Nobuharu; Tashimo, Hiroyuki; Asari, Isao; Tajiri, Tomoko; Niimi, Akio; Nagase, Hiroyuki; Matsui, Hirotoshi; Kobayashi, Nobuyuki; Shoji, Shunsuke; Ohta, Ken
2018-01-01
Omalizumab, a humanized anti-IgE monoclonal antibody, is the first molecularly targeted drug for severe asthmatics. However, responses to omalizumab vary widely among patients. This study aimed to assess the potential of baseline serum cytokine levels as predictors of responsiveness to omalizumab. Thirty-one patients with severe, persistent asthma were enrolled in this study and administered omalizumab for at least 1 year. Response to omalizumab was assessed based on the physician's global evaluation of treatment effectiveness (GETE) at 48 weeks of treatment. Blood samples were collected at baseline and 16 and 32 weeks after starting omalizumab and measured for 30 cytokines by Luminex 200 and ELISA. Exhaled nitric oxide (FeNO) levels, peripheral blood eosinophil counts, pre-bronchodilator pulmonary functions and Asthma Quality of Life Questionnaire scores were determined at baseline and 16, 32 and 48 weeks after starting omalizumab. The numbers of clinically significant asthma exacerbations in the previous year and during 48 weeks of treatment with omalizumab were assessed. GETE assessment showed 19 responders (61.3%) and 12 non-responders (38.7%). Responders showed significantly higher levels of CXCL10 and IL-12 at baseline compared to non-responders (CXCL10: responders, 1530.0 ± 315.2 pg/ml vs. non-responders, 1066.0 ± 396.8 pg/ml, P = 0.001; IL-12: responders, 60.2 ± 39.2 pg/ml vs. non-responders, 32.2 ± 26.3 pg/ml, P = 0.04). ROC curves to distinguish responders from non-responders using the baseline serum CXCL10 level showed a good AUC of 0.83. At 32 weeks of omalizumab therapy, serum CXCL10 tended to be increased (1350 ± 412.3 pg/ml at baseline vs. 1529 ± 637.6 pg/ml at 32 weeks, P = 0.16) and serum IL-12 tended to be decreased (49.4 ± 37.0 pg/ml at baseline vs. 43.9 ± 30.9 pg/ml at 32 weeks, P = 0.05). On the other hand, serum IL-5 and PDGF were significantly decreased (IL-5: 54.2 ± 13.8 pg/ml at baseline vs. 49.1 ± 12.5 pg/ml at 32 weeks, P = 0.008; PDGF: 4821 ± 2458 pg/ml at baseline vs. 4219 ± 1951 pg/ml at 32 weeks, P = 0.048). High baseline serum CXCL10 and IL-12 levels may be useful in predicting a good omalizumab response in severe asthmatics. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kim, Yu-Jin; Lee, Ok Ran; Oh, Ji Yeon; Jang, Moon-Gi; Yang, Deok-Chun
2014-01-01
Ginsenosides are glycosylated triterpenes that are considered to be important pharmaceutically active components of the ginseng (Panax ginseng ‘Meyer’) plant, which is known as an adaptogenic herb. However, the regulatory mechanism underlying the biosynthesis of triterpene saponin through the mevalonate pathway in ginseng remains unclear. In this study, we characterized the role of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) concerning ginsenoside biosynthesis. Through analysis of full-length complementary DNA, two forms of ginseng HMGR (PgHMGR1 and PgHMGR2) were identified as showing high sequence identity. The steady-state mRNA expression patterns of PgHMGR1 and PgHMGR2 are relatively low in seed, leaf, stem, and flower, but stronger in the petiole of seedling and root. The transcripts of PgHMGR1 were relatively constant in 3- and 6-year-old ginseng roots. However, PgHMGR2 was increased five times in the 6-year-old ginseng roots compared with the 3-year-old ginseng roots, which indicates that HMGRs have constant and specific roles in the accumulation of ginsenosides in roots. Competitive inhibition of HMGR by mevinolin caused a significant reduction of total ginsenoside in ginseng adventitious roots. Moreover, continuous dark exposure for 2 to 3 d increased the total ginsenosides content in 3-year-old ginseng after the dark-induced activity of PgHMGR1. These results suggest that PgHMGR1 is associated with the dark-dependent promotion of ginsenoside biosynthesis. We also observed that the PgHMGR1 can complement Arabidopsis (Arabidopsis thaliana) hmgr1-1 and that the overexpression of PgHMGR1 enhanced the production of sterols and triterpenes in Arabidopsis and ginseng. Overall, this finding suggests that ginseng HMGRs play a regulatory role in triterpene ginsenoside biosynthesis. PMID:24569845
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pyle, Moira L.; Walter, William R.; Pasyanos, Michael E.
Here, we develop high–resolution, laterally varying attenuation models for the regional crustal phases of Pg and Lg in the area surrounding the Basin and Range Province in the western United States. The models are part of the characterization effort for the Source Physics Experiment (SPE), a series of chemical explosions at the Nevada National Security Site designed to improve our understanding of explosion source phenomenology. To aid in SPE modeling efforts, we focus on improving our ability to accurately predict amplitudes in a set of narrow frequency bands ranging from 0.5 to 16.0 Hz. To explore constraints at higher frequenciesmore » where data become more sparse, we test the robustness of the empirically observed power–law relationship between quality factor Q and frequency (Q=Q 0f γ). Our methodology uses a staged approach to consider attenuation, physics–based source terms, site terms, and geometrical spreading contributions to amplitude measurements. Tomographic inversion results indicate that the frequency dependence is a reasonable assumption as attenuation varies laterally for this region through all frequency bands considered. Our 2D Pg and Lg attenuation models correlate with underlying physiographic provinces, with the highest Q located in the Sierra Nevada Mountains and the Colorado plateau. Compared to a best–fitting 1D model for the region, the 2D model provides an 81% variance reduction overall for Lg residuals and a 75% reduction for Pg. These detailed attenuation maps at high frequencies will facilitate further study of local and regional distance P/S amplitude discriminants that are typically used to distinguish between earthquakes and underground explosions.« less
Pyle, Moira L.; Walter, William R.; Pasyanos, Michael E.
2017-10-24
Here, we develop high–resolution, laterally varying attenuation models for the regional crustal phases of Pg and Lg in the area surrounding the Basin and Range Province in the western United States. The models are part of the characterization effort for the Source Physics Experiment (SPE), a series of chemical explosions at the Nevada National Security Site designed to improve our understanding of explosion source phenomenology. To aid in SPE modeling efforts, we focus on improving our ability to accurately predict amplitudes in a set of narrow frequency bands ranging from 0.5 to 16.0 Hz. To explore constraints at higher frequenciesmore » where data become more sparse, we test the robustness of the empirically observed power–law relationship between quality factor Q and frequency (Q=Q 0f γ). Our methodology uses a staged approach to consider attenuation, physics–based source terms, site terms, and geometrical spreading contributions to amplitude measurements. Tomographic inversion results indicate that the frequency dependence is a reasonable assumption as attenuation varies laterally for this region through all frequency bands considered. Our 2D Pg and Lg attenuation models correlate with underlying physiographic provinces, with the highest Q located in the Sierra Nevada Mountains and the Colorado plateau. Compared to a best–fitting 1D model for the region, the 2D model provides an 81% variance reduction overall for Lg residuals and a 75% reduction for Pg. These detailed attenuation maps at high frequencies will facilitate further study of local and regional distance P/S amplitude discriminants that are typically used to distinguish between earthquakes and underground explosions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pyle, Moira L.; Walter, William R.; Pasyanos, Michael E.
2017-10-24
Here, we develop high–resolution, laterally varying attenuation models for the regional crustal phases of Pg and Lg in the area surrounding the Basin and Range Province in the western United States. The models are part of the characterization effort for the Source Physics Experiment (SPE), a series of chemical explosions at the Nevada National Security Site designed to improve our understanding of explosion source phenomenology. To aid in SPE modeling efforts, we focus on improving our ability to accurately predict amplitudes in a set of narrow frequency bands ranging from 0.5 to 16.0 Hz. To explore constraints at higher frequenciesmore » where data become more sparse, we test the robustness of the empirically observed power–law relationship between quality factor Q and frequency (Q=Q 0f γ). Our methodology uses a staged approach to consider attenuation, physics–based source terms, site terms, and geometrical spreading contributions to amplitude measurements. Tomographic inversion results indicate that the frequency dependence is a reasonable assumption as attenuation varies laterally for this region through all frequency bands considered. Our 2D Pg and Lg attenuation models correlate with underlying physiographic provinces, with the highest Q located in the Sierra Nevada Mountains and the Colorado plateau. Compared to a best–fitting 1D model for the region, the 2D model provides an 81% variance reduction overall for Lg residuals and a 75% reduction for Pg. These detailed attenuation maps at high frequencies will facilitate further study of local and regional distance P/S amplitude discriminants that are typically used to distinguish between earthquakes and underground explosions.« less
Two Theories Are Better Than One
NASA Astrophysics Data System (ADS)
Jones, Robert
2008-03-01
All knowledge is of an approximate character (B. Russell, Human Knowledge, 1948, pg 497 and 507). Our formalisms abstract, idealize, and simplify (R. L. Epstein, Propositional Logics, 2001, Ch XI and E. Bender, An Intro. to Math. Modeling, 1978, pg v and 2). Each formalism is an idealization, often times approximating in its own DIFFERENT ways, each offering somewhat different coverage of the domain. Having MULTIPLE overlaping theories of a knowledge domain is then better than having just one theory (R. Jones, APS general meeting, April 2004). Theories are not unique (T. M. Mitchell, Machine Learning, 1997, pg 65-66 and Cooper, Machine Learning, vol. 9, 1992, pg 319). In the future every field will possess multiple theories of its domain and scientific work and engineering will be performed based on the ensemble predictions of ALL of these. In some cases the theories may be quite divergent, differing greatly one from the other. This idea can be considered an extension of Bohr's notion of complementarity, ``...different experimental arrangements...described by different physical concepts...together and only together exhaust the definable information we can obtain about the object.'' (H. J. Folse, The Philosophy of Neils Bohr, 1985, pg 238)
NASA Astrophysics Data System (ADS)
Miller, N. C.; Lizarralde, D.; McGuire, J.; Hole, J. A.
2006-12-01
We consider methodologies, including survey design and processing algorithms, which are best suited to imaging vertical reflectors in oceanic crust using marine seismic techniques. The ability to image the reflectivity structure of transform faults as a function of depth, for example, may provide new insights into what controls seismicity along these plate boundaries. Turning-wave migration has been used with success to image vertical faults on land. With synthetic datasets we find that this approach has unique difficulties in the deep ocean. The fault-reflected crustal refraction phase (Pg-r) typically used in pre-stack migrations is difficult to isolate in marine seismic data. An "imagable" Pg-r is only observed in a time window between the first arrivals and arrivals from the sediments and the thick, slow water layer at offsets beyond ~25 km. Ocean- bottom seismometers (OBSs), as opposed to a long surface streamer, must be used to acquire data suitable for crustal-scale vertical imaging. The critical distance for Moho reflections (PmP) in oceanic crust is also ~25 km, thus Pg-r and PmP-r are observed with very little separation, and the fault-reflected mantle refraction (Pn-r) arrives prior to Pg-r as the observation window opens with increased OBS-to-fault distance. This situation presents difficulties for "first-arrival" based Kirchoff migration approaches and suggests that wave- equation approaches, which in theory can image all three phases simultaneously, may be more suitable for vertical imaging in oceanic crust. We will present a comparison of these approaches as applied to a synthetic dataset generated from realistic, stochastic velocity models. We will assess their suitability, the migration artifacts unique to the deep ocean, and the ideal instrument layout for such an experiment.
Senescent intervertebral disc cells exhibit perturbed matrix homeostasis phenotype.
Ngo, Kevin; Patil, Prashanti; McGowan, Sara J; Niedernhofer, Laura J; Robbins, Paul D; Kang, James; Sowa, Gwendolyn; Vo, Nam
2017-09-01
Aging greatly increases the risk for intervertebral disc degeneration (IDD) as a result of proteoglycan loss due to reduced synthesis and enhanced degradation of the disc matrix proteoglycan (PG). How disc matrix PG homeostasis becomes perturbed with age is not known. The goal of this study is to determine whether cellular senescence is a source of this perturbation. We demonstrated that disc cellular senescence is dramatically increased in the DNA repair-deficient Ercc1 -/Δ mouse model of human progeria. In these accelerated aging mice, increased disc cellular senescence is closely associated with the rapid loss of disc PG. We also directly examine PG homeostasis in oxidative damage-induced senescent human cells using an in vitro cell culture model system. Senescence of human disc cells treated with hydrogen peroxide was confirmed by growth arrest, senescence-associated β-galactosidase activity, γH2AX foci, and acquisition of senescence-associated secretory phenotype. Senescent human disc cells also exhibited perturbed matrix PG homeostasis as evidenced by their decreased capacity to synthesize new matrix PG and enhanced degradation of aggrecan, a major matrix PG. of the disc. Our in vivo and in vitro findings altogether suggest that disc cellular senescence is an important driver of PG matrix homeostatic perturbation and PG loss. Published by Elsevier B.V.
Hernández-Aguas, Jorday; Montiel-Hernández, José Luis; Ruiz-Ramos, Rosa Velia; Escamilla García, Erandi; Guzmán-García, Mario Alberto; Ayón-Haro, Esperanza Raquel; Garza-Elizondo, Mario Alberto
2017-01-01
Studies have proposed that Porphyromonas gingivalis (Pg) and Tannerella forsythia (Tf) promote a nonspecific inflammatory response that could produce systemic disease. Oral inoculation of Pg and Tf on the immune and arthritis response was evaluated in BALB/C mice divided into four groups: (1) sham; (2) food contaminated with Pg/Tf; (3) complete Freund's adjuvant (CFA) + Pg/Tf; and (4) CFA alone. CFA was administered subcutaneously on days 1 and 14. The arthritis response was monitored for 21 days after day 14 of CFA administration. IL-1β and IL-6 were determined in serum. T cell activation was evaluated by CD25 in salivary lymph nodes or mouse spleen. Pad inflammation appeared by day 19 in the CFA group, but animals with bacteria inoculation presented a delay. A significant increase in IL-6 was found in Groups 3 and 4, but not with respect to IL-1β. We observed an increase in CD25 in cells derived from cervical nodes and in animals with bacteria inoculation and CFA. A local immune response was observed in mice inoculated with Pg and Tf (T cell activation); a systemic response was observed with CFA. Since pad inflammation was delayed by bacterial inoculation this suggests that local T cell activation could decrease pad inflammation. PMID:28676826
Modeling Surface Climate in US Cities Using Simple Biosphere Model Sib2
NASA Technical Reports Server (NTRS)
Zhang, Ping; Bounoua, Lahouari; Thome, Kurtis; Wolfe, Robert; Imhoff, Marc
2015-01-01
We combine Landsat- and the Moderate Resolution Imaging Spectroradiometer (MODIS)-based products in the Simple Biosphere model (SiB2) to assess the effects of urbanized land on the continental US (CONUS) surface climate. Using National Land Cover Database (NLCD) Impervious Surface Area (ISA), we define more than 300 urban settlements and their surrounding suburban and rural areas over the CONUS. The SiB2 modeled Gross Primary Production (GPP) over the CONUS of 7.10 PgC (1 PgC= 10(exp 15) grams of Carbon) is comparable to the MODIS improved GPP of 6.29 PgC. At state level, SiB2 GPP is highly correlated with MODIS GPP with a correlation coefficient of 0.94. An increasing horizontal GPP gradient is shown from the urban out to the rural area, with, on average, rural areas fixing 30% more GPP than urbans. Cities built in forested biomes have stronger UHI magnitude than those built in short vegetation with low biomass. Mediterranean climate cities have a stronger UHI in wet season than dry season. Our results also show that for urban areas built within forests, 39% of the precipitation is discharged as surface runoff during summer versus 23% in rural areas.
Opatrna, Sylvie; Lysak, Daniel; Trefil, Ladislav; Parker, Clare; Topley, Nicholas
2012-01-01
♦ Objective: In this study, we compared the activity of interleukin-6 (IL-6), a marker of ongoing peritoneal inflammation and biocompatibility, and its other signaling components, the soluble IL-6 receptor (sIL-6R) and soluble Gp130 (sGp130), in peritoneal effluent from patients treated with icodextrin-based (E) peritoneal dialysis (PD) solution and glucose-based bicarbonate/lactate–buffered (P) solution. ♦ Methods: Using baseline peritoneal ultrafiltration capacity, 33 stable incident PD patients were allocated either to P only (n = 20) or to P plus E for the overnight dwell (n = 13). We used ELISA to determine IL-6, sIL-6R, and sGp130 in timed overnight effluent at 1, 6, and 12 months after PD initiation. Flow cytometry was used to measure expression of IL-6R and Gp130 on isolated peritoneal leukocytes at the same time points. Peritonitis was an exclusion criterion. ♦ Results: At all time points, levels of IL-6 and sIL-6R, and the appearance rates of IL-6 (90.5 pg/min vs. 481.1 pg/min, p < 0.001; 138.6 pg/min vs. 1187.5 pg/min, p < 0.001; and 56.1 pg/min vs. 1386.0 pg/min, p < 0.001), sIL-6R (2035.3 pg/min vs. 4907.0 pg/min, p < 0.01; 1375.0 pg/min vs. 6348.4 pg/min, p < 0.01; and 1881.3 pg/min vs. 5437.8 pg/min, p < 0.01), and sGp130 (37.6 ng/min vs. 65.4 ng/min, p < 0.01; 39.2 ng/min vs. 80.6 ng/min, p < 0.01; 27.8 ng/min vs. 71.0 ng/min, p < 0.01) were significantly higher in peritoneal effluent from E-treated patients than from P-treated patients. Expression of IL6-R and Gp130 on individual leukocyte types isolated from PD effluent did not differ between E- and P-treated patients. The numbers of white blood cells present in effluent were higher in E-treated than in P-treated patients at all time points, but no significant differences were seen in the differential counts or in the number of exfoliated mesothelial cells. The IL-6 parameters in effluent from E-treated patients correlated with their plasma C-reactive protein. Despite the increased activation of the IL-6 system, no increase in peritoneal permeability as assessed by the dialysate-to-plasma ratio of creatinine in E effluent or by systemic inflammation was observed throughout the study. ♦ Conclusions: Higher levels of IL-6, its soluble receptors, and leukocyte expression were observed in E-treated than in P-treated patients, but this difference was not associated with alterations in peritoneal permeability or systemic inflammation during 1 year of follow-up. Leukocyte counts in effluent from E-treated patients were within the normal range previously reported for glucose solutions. This lack of clinical consequences may be a result of a parallel rise in sIL-6R and sGp130, which are known to control the biologic activity of IL-6. The utility of IL-6 level determinations, in isolation, for assessing the biocompatibility of PD solutions is questionable. PMID:22302924
Hamashima, Chisato; Sasazuki, Shizuka; Inoue, Manami; Tsugane, Shoichiro
2017-03-09
Chronic Helicobacter pylori infection plays a central role in the development of gastric cancer as shown by biological and epidemiological studies. The H. pylori antibody and serum pepsinogen (PG) tests have been anticipated to predict gastric cancer development. We determined the predictive sensitivity and specificity of gastric cancer development using these tests. Receiver operating characteristic analysis was performed, and areas under the curve were estimated. The predictive sensitivity and specificity of gastric cancer development were compared among single tests and combined methods using serum pepsinogen and H. pylori antibody tests. From a large-scale population-based cohort of over 100,000 subjects followed between 1990 and 2004, 497 gastric cancer subjects and 497 matched healthy controls were chosen. The predictive sensitivity and specificity were low in all single tests and combination methods. The highest predictive sensitivity and specificity were obtained for the serum PG I/II ratio. The optimal PG I/II cut-off values were 2.5 and 3.0. At a PG I/II cut-off value of 3.0, the sensitivity was 86.9% and the specificity was 39.8%. Even if three biomarkers were combined, the sensitivity was 97.2% and the specificity was 21.1% when the cut-off values were 3.0 for PG I/II, 70 ng/mL for PG I, and 10.0 U/mL for H. pylori antibody. The predictive accuracy of gastric cancer development was low with the serum pepsinogen and H. pylori antibody tests even if these tests were combined. To adopt these biomarkers for gastric cancer screening, a high specificity is required. When these tests are adopted for gastric cancer screening, they should be carefully interpreted with a clear understanding of their limitations.
Trends in serum relaxin concentration among elite collegiate female athletes
Dragoo, Jason L; Castillo, Tiffany N; Korotkova, Tatiana A; Kennedy, Ashleigh C; Kim, Hyeon Joo; Stewart, Dennis R
2011-01-01
Purpose: This study was designed to investigate the relationship between serum relaxin concentration (SRC) and menstrual history and hormonal contraceptive use among elite collegiate female athletes. Evaluation of SRC in athletes is necessary, because relaxin has been associated with increased knee joint laxity and decreased anterior cruciate ligament (ACL) strength in animal models. Methods: National Collegiate Athletic Association Division I female athletes participating in sports at high risk for ACL tears – basketball, field hockey, gymnastics, lacrosse, soccer, and volleyball – were invited to participate. All participants completed a questionnaire about their menstrual history and hormonal contraceptive use. Venipuncture was performed to obtain samples of serum progesterone and relaxin. Samples were obtained during the mid-luteal phase from ovulating participants, and between the actual or projected cycle days 21 to 24, from anovulatory participants. Serum concentration of relaxin and progesterone was determined by ELISA and the data were analyzed using SPSS statistical software with significance set at P = 0.05. Results: 169 female athletes participated. The mean SRC among all participants was 3.08 ± 6.66 pg/mL). The mean SRC differed significantly between those participants using hormonal contraceptives (1.41 pg/mL) and those not using hormonal contraceptives (3.08 pg/mL, P = 0.002). Mean SRC was lowest among amenorrheic participants (1.02 pg/mL) and highest among oligomenorrheic participants (3.71 pg/mL) and eumenorrheic participants (3.06 pg/mL); these differences were not significant (P = 0.53). Mean serum progesterone concentration (SPC) differed significantly between those participants using hormonal contraceptives (2.80 ng/mL), and those not using hormonal contraceptives (6.99 ng/mL, P < 0.0001). Conclusions: There is a positive correlation between serum progesterone and SRC and an attenuation of SRC with hormonal contraceptive use. Our results underscore the significant role that hormonal contraceptives can play in decreasing relaxin levels, if future investigations establish a link between relaxin levels and ligamentous injury among female athletes. PMID:21339934
IL8 and IL16 levels indicate serum and plasma quality.
Kofanova, Olga; Henry, Estelle; Quesada, Rocio Aguilar; Bulla, Alexandre; Linares, Hector Navarro; Lescuyer, Pierre; Shea, Kathi; Stone, Mars; Tybring, Gunnel; Bellora, Camille; Betsou, Fay
2018-02-09
Longer pre-centrifugation times alter the quality of serum and plasma samples. Markers for such delays in sample processing and hence for the sample quality, have been identified. Twenty cytokines in serum, EDTA plasma and citrate plasma samples were screened for changes in concentration induced by extended blood pre-centrifugation delays at room temperature. The two cytokines that showed the largest changes were further validated for their "diagnostic performance" in identifying serum or plasma samples with extended pre-centrifugation times. In this study, using R&D Systems ELISA kits, EDTA plasma samples and serum samples with a pre-centrifugation delay longer than 24 h had an IL16 concentration higher than 313 pg/mL, and an IL8 concentration higher than 125 pg/mL, respectively. EDTA plasma samples with a pre-centrifugation delay longer than 48 h had an IL16 concentration higher than 897 pg/mL, citrate plasma samples had an IL8 concentration higher than 21.5 pg/mL and serum samples had an IL8 concentration higher than 528 pg/mL. These robust and accurate tools, based on simple and commercially available ELISA assays can greatly facilitate qualification of serum and plasma legacy collections with undocumented pre-analytics.
Shao, Junjiong; Zhou, Xuhui; Luo, Yiqi; ...
2016-04-28
Here, despite the importance of net primary productivity (NPP) and net biome productivity (NBP), estimates of NPP and NBP for China are highly uncertain. To investigate the main sources of uncertainty, we synthesized model estimates of NPP and NBP for China from published literature and the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP). The literature-based results showed that total NPP and NBP in China were 3.35 ± 1.25 and 0.14 ± 0.094 Pg C yr –1, respectively. Classification and regression tree analysis based on literature data showed that model type was the primary source of the uncertainty, explaining 36%more » and 64% of the variance in NPP and NBP, respectively. Spatiotemporal scales, land cover conditions, inclusion of the N cycle, and effects of N addition also contributed to the overall uncertainty. Results based on the MsTMIP data suggested that model structures were overwhelmingly important (>90%) for the overall uncertainty compared to simulations with different combinations of time-varying global change factors. The interannual pattern of NPP was similar among diverse studies and increased by 0.012 Pg C yr –1 during 1981–2000. In addition, high uncertainty in China's NPP occurred in areas with high productivity, whereas NBP showed the opposite pattern. Our results suggest that to significantly reduce uncertainty in estimated NPP and NBP, model structures should be substantially tested on the basis of empirical results. To this end, coordinated distributed experiments with multiple global change factors might be a practical approach that can validate specific structures of different models.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shao, Junjiong; Zhou, Xuhui; Luo, Yiqi
Here, despite the importance of net primary productivity (NPP) and net biome productivity (NBP), estimates of NPP and NBP for China are highly uncertain. To investigate the main sources of uncertainty, we synthesized model estimates of NPP and NBP for China from published literature and the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP). The literature-based results showed that total NPP and NBP in China were 3.35 ± 1.25 and 0.14 ± 0.094 Pg C yr –1, respectively. Classification and regression tree analysis based on literature data showed that model type was the primary source of the uncertainty, explaining 36%more » and 64% of the variance in NPP and NBP, respectively. Spatiotemporal scales, land cover conditions, inclusion of the N cycle, and effects of N addition also contributed to the overall uncertainty. Results based on the MsTMIP data suggested that model structures were overwhelmingly important (>90%) for the overall uncertainty compared to simulations with different combinations of time-varying global change factors. The interannual pattern of NPP was similar among diverse studies and increased by 0.012 Pg C yr –1 during 1981–2000. In addition, high uncertainty in China's NPP occurred in areas with high productivity, whereas NBP showed the opposite pattern. Our results suggest that to significantly reduce uncertainty in estimated NPP and NBP, model structures should be substantially tested on the basis of empirical results. To this end, coordinated distributed experiments with multiple global change factors might be a practical approach that can validate specific structures of different models.« less
Kraus, V B; Conaghan, P G; Aazami, H A; Mehra, P; Kivitz, A J; Lufkin, J; Hauben, J; Johnson, J R; Bodick, N
2018-01-01
Intra-articular (IA) corticosteroids relieve osteoarthritis (OA) pain, but rapid absorption into systemic circulation may limit efficacy and produce untoward effects. We compared the pharmacokinetics (PK) of IA triamcinolone acetonide (TA) delivered as an extended-release, microsphere-based formulation (FX006) vs a crystalline suspension (TAcs) in knee OA patients. This Phase 2 open-label study sequentially enrolled 81 patients who received a single IA injection of FX006 (5 mL, 32 mg delivered dose, N = 63) or TAcs (1 mL, 40 mg, N = 18). Synovial fluid (SF) aspiration was attempted in each patient at baseline and one post-IA-injection visit (FX006: Week 1, Week 6, Week 12, Week 16 or Week 20; TAcs: Week 6). Blood was collected at baseline and multiple post-injection times. TA concentrations (validated LC-MS/MS, geometric means (GMs)), PK (non-compartmental analysis models), and adverse events (AEs) were assessed. SF TA concentrations following FX006 were quantifiable through Week 12 (pg/mL: 231,328.9 at Week 1; 3590.0 at Week 6; 290.6 at Week 12); post-TAcs, only two of eight patients had quantifiable SF TA at Week 6 (7.7 pg/mL). Following FX006, plasma TA gradually increased to peak (836.4 pg/mL) over 24 h and slowly declined to <110 pg/mL over Weeks 12-20; following TAcs, plasma TA peaked at 4 h (9628.8 pg/mL), decreased to 4991.1 pg/mL at 24 h, and was 149.4 pg/mL at Week 6, the last post-treatment time point assessed. AEs were similar between groups. In knee OA patients, microsphere-based TA delivery via a single IA injection prolonged SF joint residency, diminished peak plasma levels, and thus reduced systemic TA exposure relative to TAcs. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Romanczuk-Seiferth, Nina; Koehler, Saskia; Dreesen, Caspar; Wüstenberg, Torsten; Heinz, Andreas
2015-05-01
Pathological gambling (PG) shares clinical characteristics such as craving and loss of control with substance use disorders and is thus considered a behavioral addiction. While functional alterations in the mesolimbic reward system have been correlated with craving and relapse in substance use disorders, only a few studies have examined this brain circuit in PG, and no direct comparison has been conducted so far. Thus, we investigated the neuronal correlates of reward processing in PG in contrast to alcohol-dependent (AD) patients and healthy subjects. Eighteen PG patients, 15 AD patients and 17 controls were investigated with a monetary incentive delay task, in which visual cues predict the consequence (monetary gain, avoidance of loss, none) of a fast response to a subsequent target stimulus. Functional magnetic resonance imaging data were analyzed to account for possible confounding factors such as local gray matter volume. Activity in the right ventral striatum during loss anticipation was increased in PG patients compared with controls and AD patients. Moreover, PG patients showed decreased activation in the right ventral striatum and right medial prefrontal cortex during successful loss avoidance compared with controls, which was inversely associated with severity of gambling behavior. Thus, despite neurobiological similarities to substance use disorders in reward processing, as reported by previous studies, we found relevant differences with respect to the anticipation of loss as well as its avoidance (negative reinforcement), which further contributes to the understanding of PG. © 2014 Society for the Study of Addiction.
Errandonea, N; Fierro, S; Viñoles, C; Gil, J; Banchero, G; Olivera-Muzante, J
2018-03-21
The aim of this study was to evaluate the reproductive impact of a short-term protein supplementation on a long interval prostaglandin-based protocol (two PG injections 15 d apart; PG15) for timed artificial insemination in sheep. During the breeding season, 437 multiparous Merino ewes grazing native pastures (forage allowance of 6 kg of dry matter/100 kg of live weight; crude protein: 10.8%, metabolic energy: 2.1 Mcal/kg of dry matter) were selected. Ewes were allocated, according to body condition score (3.2 ± 0.2) and body weight (40.6 ± 4.9 kg, mean ± SD), to a 2 × 2 factorial design: type of estrus -spontaneous estrus (SE) or induced with PG15 (PG15)-, and supplementation (yes or no) before insemination (+FF; soybean meal at Days -10 to -3; crude protein: 51.9%, metabolic energy: 2.8 Mcal/kg of dry matter; average consumption 0.9% live weight/ewe/day of dry matter). All ewes were cervically artificial inseminated (Day -2 to -3 in SE ewes at estrus detection; Day 0 = timed artificial insemination in PG15 ewes). Ovulation rate on Day 7, non-return to service on Day 23, conception, fertility, prolificacy and fecundity on Day 60 were evaluated. Ovulation rate (1.17 ± 0.40 vs. 1.06 ± 0.25), non-return to service at Day 23 (81.7 vs. 64.2%), conception (78.8 vs. 61.5%), fertility (75.2 vs. 61.5%) and fecundity (0.77 vs. 0.62) were higher in ewes from SE than PG15 group (P < 0.05). However, no differences were observed in prolificacy (1.02 ± 0.16 vs. 1.01 ± 0,12) between groups (P > 0.05). Protein supplementation increased ovulation rate (1.30 ± 0.45 vs. 1.17 ± 0.40), prolificacy (1.18 ± 0.39 vs. 1.02 ± 0.16) and fecundity (0.94 vs. 0.77%; P < 0.05), but not non-return to service on Day 23 (83.8 vs. 81.7%), conception (82.9 vs. 78.8%) or fertility (79.1 vs. 75.2%; P > 0.05) in SE group. The supplement feed to PG15 ewes increased ovulation rate (1.35 ± 0.45 vs. 1.06 ± 0.25), prolificacy (1.25 ± 0.43 vs. 1.01 ± 0.12) and fecundity (0.79 vs. 0.62%; P < 0.05) to levels comparable to SE + FF ewes (P > 0.05). The magnitude of the increase in ovulation rate in PG15 was greater than in the SE group (27 vs. 11%; P < 0.05). However, non-return to service on Day 23 (65.1 vs. 64.2%), conception (63.3 vs 61.5%), and fertility rate (63.3 vs. 61.5%; P < 0.05) remained similar in PG15 supplemented or not supplemented ewes. In conclusion, a short-term protein supplementation before cervical time artificial insemination improved the reproductive performance of ewes synchronized with the PG15 protocol to levels comparable to the SE group. Copyright © 2018 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Russo, Paola; Hu, Anming; Compagnini, Giuseppe; Duley, Walter W.; Zhou, Norman Y.
2014-01-01
Porous graphene (PG) and graphene quantum dots (GQDs) are attracting attention due to their potential applications in photovoltaics, catalysis, and bio-related fields. We present a novel way for mass production of these promising materials. The femtosecond laser ablation of highly oriented pyrolytic graphite (HOPG) is employed for their synthesis. Porous graphene (PG) layers were found to float at the water-air interface, while graphene quantum dots (GQDs) were dispersed in the solution. The sheets consist of one to six stacked layers of spongy graphene, which form an irregular 3D porous structure that displays pores with an average size of 15-20 nm. Several characterization techniques have confirmed the porous nature of the collected layers. The analyses of the aqueous solution confirmed the presence of GQDs with dimensions of about 2-5 nm. It is found that the formation of both PG and GQDs depends on the fs-laser ablation energy. At laser fluences less than 12 J cm-2, no evidence of either PG or GQDs is detected. However, polyynes with six and eight carbon atoms per chain are found in the solution. For laser energies in the 20-30 J cm-2 range, these polyynes disappeared, while PG and GQDs were found at the water-air interface and in the solution, respectively. The origin of these materials can be explained based on the mechanisms for water breakdown and coal gasification. The absence of PG and GQDs, after the laser ablation of HOPG in liquid nitrogen, confirms the proposed mechanisms.Porous graphene (PG) and graphene quantum dots (GQDs) are attracting attention due to their potential applications in photovoltaics, catalysis, and bio-related fields. We present a novel way for mass production of these promising materials. The femtosecond laser ablation of highly oriented pyrolytic graphite (HOPG) is employed for their synthesis. Porous graphene (PG) layers were found to float at the water-air interface, while graphene quantum dots (GQDs) were dispersed in the solution. The sheets consist of one to six stacked layers of spongy graphene, which form an irregular 3D porous structure that displays pores with an average size of 15-20 nm. Several characterization techniques have confirmed the porous nature of the collected layers. The analyses of the aqueous solution confirmed the presence of GQDs with dimensions of about 2-5 nm. It is found that the formation of both PG and GQDs depends on the fs-laser ablation energy. At laser fluences less than 12 J cm-2, no evidence of either PG or GQDs is detected. However, polyynes with six and eight carbon atoms per chain are found in the solution. For laser energies in the 20-30 J cm-2 range, these polyynes disappeared, while PG and GQDs were found at the water-air interface and in the solution, respectively. The origin of these materials can be explained based on the mechanisms for water breakdown and coal gasification. The absence of PG and GQDs, after the laser ablation of HOPG in liquid nitrogen, confirms the proposed mechanisms. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr05572h
Post-Vietnam military herbicide exposures in UC-123 Agent Orange spray aircraft.
Lurker, Peter A; Berman, Fred; Clapp, Richard W; Stellman, Jeanne Mager
2014-04-01
During the Vietnam War, approximately 20 million gallons of herbicides, including ~10.5 million gallons of dioxin-contaminated Agent Orange, were sprayed by about 34 UC-123 aircraft that were subsequently returned to the United States, without decontamination or testing, to three Air Force reserve units for transport operations (~1971-1982). In 1996, observed dioxin contamination led to withdrawal of these UC-123s from public auction and to their smelting in 2009. Current Air Force and Department of Veterans Affairs policies stipulate that "dried residues" of chemical herbicides and dioxin had not lead to meaningful exposures to flight crew and maintenance personnel, who are thus ineligible for Agent Orange-related benefits or medical examinations and treatment. Sparse monitoring data are available for analysis. Three complementary approaches for modeling potential exposures to dioxin in the post-Vietnam war aircraft were employed: (1) using 1994 and 2009 Air Force surface wipe data to model personnel exposures and to estimate dioxin body burden for dermal-oral exposure for dried residues using modified generic US Environmental Protection Agency intake algorithms; (2) comparing 1979 Air Force 2,4- dichlorophenoxyacetic acid and 2,4-5-trichlorophenoxyacetic acid air samples to saturated vapor pressure concentrations to estimate potential dioxin exposure through inhalation, ingestion and skin contact with contaminated air and dust; and (3) applying emission models for semivolatile organic compounds from contaminated surfaces to estimate airborne contamination. Model (1): Body-burden estimates for dermal-oral exposure were 0.92 and 5.4pg/kg body-weight-day for flight crew and maintainers. The surface wipe concentrations were nearly two orders of magnitude greater than the US Army guidance level. Model (2): measured airborne concentrations were at least five times greater than saturated vapor pressure, yielding dioxin estimates that ranged from 13.2-27.0pg/m(3), thus supporting the likelihood of dioxin dust adsorption. Model (3): Theoretical models yielded consistent estimates to Model 2, 11-49pg/m(3), where the range reflects differences in experimental value of dioxin vapor pressure and surface area used. Model (3) results also support airborne contamination and dioxin dust adsorption. Inhalation, ingestion and skin absorption in aircrew and maintainers were likely to have occurred during post-Vietnam use of the aircraft based on the use of three complementary models. Measured and modeled values for dioxin exceeded several available guidelines. Deposition-aerosolization-redeposition homeostasis of semivolatile organic compound contaminants, particularly dioxin, is likely to have continually existed within the aircraft. Current Air Force and Department of Veterans Affairs policies are not consistent with the available industrial hygiene measurements or with the widely accepted models for semivolatile organic compounds. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Kaur, Gagandeep; Gupta, Shuchi; Sachdeva, Ritika; Dharamvir, Keya
2018-05-01
Adsorption of small gas molecules (such as CO and O2) on pristine graphene (PG) and Li-adsorbed graphene (PG-Li) have been investigated using first principles methods within density functional theory (DFT). We also notice that PG-Li has a higher chemical reactivity towards the gas molecules as compared to PG and these molecules have higher adsorption energy on this surface. Moreover, the strong interactions between PG-Li and the adsorbed molecules (as compared to PG and gas molecules) induce dramatic changes to the electronic properties of PG adsorbed with Li and make PG-Li a promising candidate as sensing material for CO and O2 gases.
Association Between Gambling and Exposure to Guns Among Cocaine-Using Women.
Vaddiparti, Krishna; Striley, Catherine W; Cottler, Linda B
2016-09-01
The purpose of this study is to assess the association between gambling severity and exposure to guns among substance-using women recruited in the community. Data for these analyses come from the baseline phase of two community-based HIV prevention interventions conducted among alcohol and drug-using women in St. Louis, MO. Gun exposure was assessed using the Violence Exposure Questionnaire (VEQ), and DSM-IV pathological gambling (PG) symptoms and other psychiatric symptoms were assessed using the Computerized Diagnostic Interview Schedule; The Composite International Diagnostic Interview Substance Abuse Module assessed DSM-IV substance dependence, including cocaine dependence and alcohol dependence. Women in the study were predominantly African American (80%), mean age was 35.70 years ±8.8. Women exposed to guns were significantly more likely than women not exposed to guns to have gambled with all consequences: without meeting PG criteria (21% vs. 15%); to meet 1 to 4 PG criteria (22% vs. 12%), and to report 5 or more PG criteria (10% vs. 5%). These differences were significant at p < 0.0001. Based on the multivariate analysis, women who gambled without PG symptoms (OR = 1.77; 95% CI = 1.10-2.85) were nearly twice more likely to have exposure to guns than women who did not gamble. The risk for gun exposure increased with severity of gambling. Women who gambled and reported one to four PG criteria were twice as likely to have had an exposure to guns (OR 2.04; 95% CI = 1.45-3.06) and this risk increased to nearly threefold among women who met five or more criteria of PG (OR 2.65; 95% CI = 1.32-5.32). In addition, endorsing five or more criteria for major depressive disorder (OR 1.44; 95% CI = 1.00-2.06) and three or more criteria for antisocial personality adult criteria (OR 3.78; 95% CI = 2.03-7.02) were strong predictors for gun exposure among these women. The findings indicate that substance-using women with gambling behavior are at an enhanced risk to have exposure to guns.
On the structure of an aqueous propylene glycol solution.
Rhys, Natasha H; Gillams, Richard J; Collins, Louise E; Callear, Samantha K; Lawrence, M Jayne; McLain, Sylvia E
2016-12-14
Using a combination of neutron diffraction and empirical potential structure refinement computational modelling, the interactions in a 30 mol. % aqueous solution of propylene glycol (PG), which govern both the hydration and association of this molecule in solution, have been assessed. From this work it appears that PG is readily hydrated, where the most prevalent hydration interactions were found to be through both the PG hydroxyl groups but also alkyl groups typically considered hydrophobic. Hydration interactions of PG dominate the solution over PG self-self interactions and there is no evidence of more extensive association. This hydration behavior for PG in solutions suggests that the preference of PG to be hydrated rather than to be self-associated may translate into a preference for PG to bind to lipids rather than itself, providing a potential explanation for how PG is able to enhance the apparent solubility of drug molecules in vivo.
On the structure of an aqueous propylene glycol solution
NASA Astrophysics Data System (ADS)
Rhys, Natasha H.; Gillams, Richard J.; Collins, Louise E.; Callear, Samantha K.; Lawrence, M. Jayne; McLain, Sylvia E.
2016-12-01
Using a combination of neutron diffraction and empirical potential structure refinement computational modelling, the interactions in a 30 mol. % aqueous solution of propylene glycol (PG), which govern both the hydration and association of this molecule in solution, have been assessed. From this work it appears that PG is readily hydrated, where the most prevalent hydration interactions were found to be through both the PG hydroxyl groups but also alkyl groups typically considered hydrophobic. Hydration interactions of PG dominate the solution over PG self-self interactions and there is no evidence of more extensive association. This hydration behavior for PG in solutions suggests that the preference of PG to be hydrated rather than to be self-associated may translate into a preference for PG to bind to lipids rather than itself, providing a potential explanation for how PG is able to enhance the apparent solubility of drug molecules in vivo.
Sow, Li Cheng; Kong, Karmaine; Yang, Hongshun
2018-05-01
Pork gelatin is not suitable for halal and kosher application; however, fish gelatin (FG) can be modified for use as a pork gelatin (PG) mimetic. Herein, low-acyl gellan (GE), κ-carrageenan (KC), and salts (CaCl 2 or KCl) were combined with a 180 Bloom tilapia FG. A formulation comprising 5.925% (w/v) FG + 0.025% (w/v) GE + 3mM CaCl 2 best matched the physicochemical properties of PG. The modification increased the FG gel strength from 115 ± 2 to 149 ± 2 g (matching the 148 ± 2 of PG), while the T m increased from 27.9 ± 1.0 to 32.4 ± 0.8 °C (matching the 33.1 ± 0.3 °C of PG). Nanoaggregates (diameter between 150 and 300 nm) could be an important structural factor affecting the physicochemical properties, as both PG and GE-modified FG showed a similar frequency distribution in this size group (57.4 ± 1.6% (PG) compared with 56.3 ± 2.2% (modified FG)). To further explore the differences between KC and GE in modifying of FG's structure, the FG-KC and FG-GE gels were compared. The zeta potential and Fourier transform infrared (FTIR) spectroscopy results for the FG-KC gel supported an associative interaction with complex formation, as indicated from the large aggregates and amorphous phase under atomic force microscopy (AFM). Contrastingly, a segregative FG-GE interaction took place in presence of CaCl 2 . These structures and interaction differences between FG-GE and FG-KC influenced the macro-properties of FG, possibly explaining the differences in the modification of the melting temperature of FG. A diagram representing the interaction-structure-physicochemical properties was proposed to explain the differences between the FG-GE and FG-KC gels. Certain people cannot consume any pork product or derivatives for religious reasons, thus it is essential to find a pork gelatin (PG) substitute for food product development. The commonly used polysaccharides, gellan and carrageenan, together with salt, can be added to fish gelatin (FG) to match the textural properties of PG, representing a promising substitute for PG. The difference in the mechanism of gellan and carrageenan to improve properties of FG has been revealed from nanostructure level. The use of food grade ingredients and simple mixing process are favorable in the food industry. © 2018 Institute of Food Technologists®.
Fukuda, Chihiro; Yahata, Chie; Kinoshita, Takuya; Watanabe, Takafumi; Tsukamoto, Hideo; Mochizuki, Akira
2017-10-01
It is well known that polyether-based copolymers have good blood compatibility, although many mechanisms have been proposed to explain their favorable performance. Our objective in carrying out the present study was to obtain a better understanding of the effect of the (poly)ether segment on blood compatibility. Therefore, we synthesized poly(propylene glycol) (PPG)-based initiators for atom transfer polymerization, where the number of propylene glycol (PG) units in the PPG (Pn(PG) was varied from 1 to 94. Methyl methacrylate (MMA) was polymerized using the initiators, resulting in the formation of polyMMAs with a PG-based ether part at the polymer terminal. We mainly investigated the effects of Pn(PG) on the surface properties and platelet compatibility of the PPG-polyMMA. X-ray photoelectron spectroscopy and surface contact angle (CA) analysis revealed the exposure of the PG units at the surface of the polymer. The platelet compatibility of the polymers was improved compared with a commercial polyMMA, even when Pn(PG) = 1. These results suggest that PG units have an important influence on favorable blood compatibility, regardless of the Pn(PG) value. We also investigated protein adsorption behavior in terms of the amount and deformation of fibrinogen adsorbed on the polymer surface.
Assessing nutritional status in cancer: role of the Patient-Generated Subjective Global Assessment.
Jager-Wittenaar, Harriët; Ottery, Faith D
2017-09-01
The Scored Patient-Generated Subjective Global Assessment (PG-SGA) is used internationally as the reference method for proactive risk assessment (screening), assessment, monitoring and triaging for interventions in patients with cancer. This review aims to explain the rationale behind and data supporting the PG-SGA, and to provide an overview of recent developments in the utilization of the PG-SGA and the PG-SGA Short Form. The PG-SGA was designed in the context of a paradigm known as 'anabolic competence'. Uniquely, the PG-SGA evaluates the patient's status as a dynamic rather than static process. The PG-SGA has received new attention, particularly as a screening instrument for nutritional risk or deficit, identifying treatable impediments and guiding patients and professionals in triaging for interdisciplinary interventions. The international use of the PG-SGA indicates a critical need for high-quality and linguistically validated translations of the PG-SGA. As a 4-in-1 instrument, the PG-SGA can streamline clinic work flow and improve the quality of interaction between the clinician and the patient. The availability of multiple high-quality language versions of the PG-SGA enables the inclusion of the PG-SGA in international multicenter studies, facilitating meta-analysis and benchmarking across countries.
Biosphere model simulations of interannual variability in terrestrial 13C/12C exchange
NASA Astrophysics Data System (ADS)
van der Velde, I. R.; Miller, J. B.; Schaefer, K.; Masarie, K. A.; Denning, S.; White, J. W. C.; Tans, P. P.; Krol, M. C.; Peters, W.
2013-09-01
Previous studies suggest that a large part of the variability in the atmospheric ratio of 13CO2/12CO2originates from carbon exchange with the terrestrial biosphere rather than with the oceans. Since this variability is used to quantitatively partition the total carbon sink, we here investigate the contribution of interannual variability (IAV) in biospheric exchange to the observed atmospheric 13C variations. We use the Simple Biosphere - Carnegie-Ames-Stanford Approach biogeochemical model, including a detailed isotopic fractionation scheme, separate 12C and 13C biogeochemical pools, and satellite-observed fire disturbances. This model of 12CO2 and 13CO2 thus also produces return fluxes of 13CO2from its differently aged pools, contributing to the so-called disequilibrium flux. Our simulated terrestrial 13C budget closely resembles previously published model results for plant discrimination and disequilibrium fluxes and similarly suggests that variations in C3 discrimination and year-to-year variations in C3and C4 productivity are the main drivers of their IAV. But the year-to-year variability in the isotopic disequilibrium flux is much lower (1σ=±1.5 PgC ‰ yr-1) than required (±12.5 PgC ‰ yr-1) to match atmospheric observations, under the common assumption of low variability in net ocean CO2 fluxes. This contrasts with earlier published results. It is currently unclear how to increase IAV in these drivers suggesting that SiBCASA still misses processes that enhance variability in plant discrimination and relative C3/C4productivity. Alternatively, 13C budget terms other than terrestrial disequilibrium fluxes, including possibly the atmospheric growth rate, must have significantly different IAV in order to close the atmospheric 13C budget on a year-to-year basis.
Nomura, Tsutomu; Ushio, Munetaka; Kondo, Kenji; Yamasoba, Tatsuya
2015-11-01
The purpose of this research is to determine the cause of nasal perforation symptoms and to predict post-operative function after nasal perforation repair surgery. A realistic three-dimensional (3D) model of the nose with a septal perforation was reconstructed using a computed tomography (CT) scan from a patient with nasal septal defect. The numerical simulation was carried out using ANSYS CFX V13.0. Pre- and post-operative models were compared by their velocity, pressure gradient (PG), wall shear (WS), shear strain rate (SSR) and turbulence kinetic energy in three plains. In the post-operative state, the crossflows had disappeared, and stream lines bound to the olfactory cleft area had appeared. After surgery, almost all of high-shear stress areas were disappeared comparing pre-operative model. In conclusion, the effects of surgery to correct nasal septal perforation were evaluated using a three-dimensional airflow evaluation. Following the surgery, crossflows disappeared, and WS, PG and SSR rate were decreased. A high WS.PG and SSR were suspected as causes of nasal perforation symptoms.
Decadal trends in regional CO2 fluxes estimated from atmospheric inversions
NASA Astrophysics Data System (ADS)
Saeki, T.; Patra, P. K.
2016-12-01
Top-down approach (or atmospheric inversion) using atmospheric transport models and CO2 observations are an effective way to optimize surface fluxes at subcontinental scales and monthly time intervals. We used the CCSR/NIES/FRCGC AGCM-based Chemistry Transport Model (JAMSTEC's ACTM) and atmospheric CO2 concentrations at NOAA, CSIRO, JMA, NIES, NIES-MRI sites from Obspack GLOBALVIEW-CO2 data product (2013) for estimating CO2 fluxes for the period of 1990-2011. Carbon fluxes were estimated for 84 partitions (54 lands + 30 oceans) of the globe by using a Bayesian synthesis inversion framework. A priori fluxes are (1) atmosphere-ocean exchange from Takahashi et al. (2009), (2) 3-hourly terrestrial biosphere fluxes (annually balanced) from CASA model, and (3) fossil fuel fluxes from CDIAC global totals and EDGAR4.2 spatial distributions. Four inversion cases have been tested with 1) 21 sites (sites which have real data fraction of 90 % or more for 1989-2012), 2) 21 sites + CONTRAIL data, 3) 66 sites (over 70 % coverage), and 4) 157 sites. As a result of time-dependent inversions, mean total flux (excluding fossil fuel) for the period 1990-2011 is estimated to be -3.09 ±0.16 PgC/yr (mean and standard deviation of the four cases), where land (incl. biomass burning and land use change) and ocean absorb an average rate of -1.80 ±0.18 and -1.29 ±0.08 PgC/yr, respectively. The average global total sink from 1991-2000 to 2001-2010 increases by about 0.5 PgC/yr, mainly due to the increase in northern and tropical land sinks (Africa, Boreal Eurasia, East Asia and Europe), while ocean sinks show no clear trend. Inversion with CONTRAIL data estimates large positive flux anomalies in late 1997 associated with the 1997/98 El-Nino, while inversion without CONTARIL data between Japan and Australia fails to estimate such large anomalies. Acknowledgements. This work is supported by the Environment Research and Technology Development Fund (2-1401) of the Ministry of the Environment, Japan. We thank all measurement groups for submitting CO2 concentration data to the obspack-GLOBALVIEW product.
NASA Astrophysics Data System (ADS)
Almatroushi, H. R.; Lootah, F. H.; Deighan, J.; Fillingim, M. O.; Jain, S.; Bougher, S. W.; England, S.; Schneider, N. M.
2017-12-01
This research focuses on developing empirical and theoretical models for OI 135.6 nm and CO 4PG band system FUV dayglow emissions in the Martian thermosphere as predicted to be seen from the Emirates Mars Ultraviolet Spectrometer (EMUS), one of the three scientific instruments aboard the Emirates Mars Mission (EMM) to be launched in 2020. These models will aid in simulating accurate disk radiances which will be utilized as an input to an EMUS instrument simulator. The developed zonally averaged empirical models are based on FUV data from the IUVS instrument onboard the MAVEN mission, while the theoretical models are based on a basic Chapman profile. The models calculate the brightness (B) of those emissions taking into consideration observation geometry parameters such as emission angle (EA), solar zenith angle (SZA) and planet distance from the sun (Ds). Specifically, the empirical models takes a general form of Bn=A*cos(SZA)n/cos(EA)m , where Bn is the normalized brightness value of an emission feature, and A, n, and m are positive constant values. The model form shows that the brightness has a positive correlation with EA and a negative correlation with SZA. A comparison of both models are explained in this research while examining full Mars and half Mars disk images generated using geometry code specially developed for the EMUS instrument. Sensitivity analyses have also been conducted for the theoretical modeling to observe the contributions of electron impact on atomic oxygen and CO2 to the brightness of OI 135.6nm, in addition to the effect of electron temperature on the CO2± dissociative recombination contribution to the CO 4PG band system.
Li, Qiudan; Zhan, Yongcheng; Wang, Lei; Leischow, Scott J; Zeng, Daniel Dajun
2016-07-30
The electronic cigarette (e-cigarette) market has grown rapidly in recent years. However, causes of e-cigarette related symptoms among users and their impact on health remain uncertain. This research aims to mine the potential relationships between symptoms and e-liquid components, such as propylene glycol (PG), vegetable glycerine (VG), flavor extracts, and nicotine, using user-generated data collected from Reddit. A total of 3605 e-liquid related posts from January 1st, 2011 to June 30th, 2015 were collected from Reddit. Then the patterns of VG/PG distribution among different flavors were analyzed. Next, the relationship between throat hit, which was a typical symptom of e-cigarette use, and e-liquid components was studied. Finally, other symptoms were examined based on e-liquid components and user sentiment. We discovered 3 main sets of findings: 1) We identified three groups of flavors in terms of VG/PG ratios. Fruits, cream, and nuts flavors were similar. Sweet, menthol, and seasonings flavors were classified into one group. Tobacco and beverages flavors were the third group. 2) Throat hit was analyzed and we found that menthol and tobacco flavors, as well as high ratios of PG and nicotine level, could produce more throat hit. 3) A total of 9 systems of 25 symptoms were identified and analyzed. Components including VG/PG ratio, flavor, and nicotine could be possible reasons for these symptoms. E-liquid components shown to be associated with e-cigarette use symptomology were VG/PG ratios, flavors, and nicotine levels. Future analysis could be conducted based on the structure of e-liquid components categories built in this study. Information revealed in this study could be utilized by e-cigarette users to understand the relationship between e-liquid type and symptoms experienced, by vendors to choose appropriate recipes of e-liquid, and by policy makers to develop new regulations.
Low-dose 4D cardiac imaging in small animals using dual source micro-CT
NASA Astrophysics Data System (ADS)
Holbrook, M.; Clark, D. P.; Badea, C. T.
2018-01-01
Micro-CT is widely used in preclinical studies, generating substantial interest in extending its capabilities in functional imaging applications such as blood perfusion and cardiac function. However, imaging cardiac structure and function in mice is challenging due to their small size and rapid heart rate. To overcome these challenges, we propose and compare improvements on two strategies for cardiac gating in dual-source, preclinical micro-CT: fast prospective gating (PG) and uncorrelated retrospective gating (RG). These sampling strategies combined with a sophisticated iterative image reconstruction algorithm provide faster acquisitions and high image quality in low-dose 4D (i.e. 3D + Time) cardiac micro-CT. Fast PG is performed under continuous subject rotation which results in interleaved projection angles between cardiac phases. Thus, fast PG provides a well-sampled temporal average image for use as a prior in iterative reconstruction. Uncorrelated RG incorporates random delays during sampling to prevent correlations between heart rate and sampling rate. We have performed both simulations and animal studies to validate these new sampling protocols. Sampling times for 1000 projections using fast PG and RG were 2 and 3 min, respectively, and the total dose was 170 mGy each. Reconstructions were performed using a 4D iterative reconstruction technique based on the split Bregman method. To examine undersampling robustness, subsets of 500 and 250 projections were also used for reconstruction. Both sampling strategies in conjunction with our iterative reconstruction method are capable of resolving cardiac phases and provide high image quality. In general, for equal numbers of projections, fast PG shows fewer errors than RG and is more robust to undersampling. Our results indicate that only 1000-projection based reconstruction with fast PG satisfies a 5% error criterion in left ventricular volume estimation. These methods promise low-dose imaging with a wide range of preclinical applications in cardiac imaging.
Ruijgrok, Carolien; Dekker, Jacqueline M; Beulens, Joline W; Brouwer, Ingeborg A; Coupé, Veerle M H; Heymans, Martijn W; Sijtsma, Femke P C; Mela, David J; Zock, Peter L; Olthof, Margreet R; Alssema, Marjan
2018-01-01
Glycaemic markers and fasting insulin are frequently measured outcomes of intervention studies. To extrapolate accurately the impact of interventions on the risk of diabetes incidence, we investigated the size and shape of the associations of fasting plasma glucose (FPG), 2 h post-load glucose (2hPG), HbA 1c , fasting insulin and HOMA-IR with incident type 2 diabetes mellitus. The study population included 1349 participants aged 50-75 years without diabetes at baseline (1989) from a population-based cohort in Hoorn, the Netherlands. Incident type 2 diabetes was defined by the WHO 2011 criteria or known diabetes at follow-up. Logistic regression models were used to determine the associations of the glycaemic markers, fasting insulin and HOMA-IR with incident type 2 diabetes. Restricted cubic spline logistic regressions were conducted to investigate the shape of the associations. After a mean follow-up duration of 6.4 (SD 0.5) years, 152 participants developed diabetes (11.3%); the majority were screen detected by high FPG. In multivariate adjusted models, ORs (95% CI) for incident type 2 diabetes for the highest quintile in comparison with the lowest quintile were 9.0 (4.4, 18.5) for FPG, 6.1 (2.9, 12.7) for 2hPG, 3.8 (2.0, 7.2) for HbA 1c , 1.9 (0.9, 3.6) for fasting insulin and 2.8 (1.4, 5.6) for HOMA-IR. The associations of FPG and HbA 1c with incident diabetes were non-linear, rising more steeply at higher values. FPG was most strongly associated with incident diabetes, followed by 2hPG, HbA 1c , HOMA-IR and fasting insulin. The strong association with FPG is probably because FPG is the most frequent marker for diabetes diagnosis. Non-linearity of associations between glycaemic markers and incident type 2 diabetes should be taken into account when estimating future risk of type 2 diabetes based on glycaemic markers.
Airborne Chlordane Contamination in Houses Treated for Termites at a Midwestern Air Force Base
1981-02-01
to provide entry authorization. Inside air temperature and relative humidity were measured with a sling psychrometer at the time of sampling...of the houses had chlordane concentrations 21.0 Pg/m3. No correlation could be made between chlordane concentration and year of treatment except for...from 14.5 to 37.8 pg/m8, were found in houses treated in 1970. Correlation of chlordane concentration could not be made with barometric pressure
Arnquist, Isaac J; Hoppe, Eric J; Bliss, Mary; Grate, Jay W
2017-03-07
A rapid new method for determining the U and Th mass concentrations in high radiopurity plastics is described, consisting of (1) dry ashing the plastic sample and tracers in low mass crucibles made of ultra low background electroformed copper (ULB EF-Cu) foil cut and folded into boats, (2) dissolving both the ash and the boat in acid, (3) performing a column separation to remove copper, and (4) determining the elements of interest by isotope dilution mass spectrometry. This method was demonstrated on both unfluorinated and fluorinated plastics, demonstrating high tracer recoveries and detection limits to pg/g (i.e., parts per trillion) levels or below, corresponding to μBq/kg of material. Samples of biomedical polyester (Max-Prene 955) and a fluoropolymer (polyvinylidene fluoride, PVDF) were analyzed in powder raw material forms as well as solids in the form of pellets or injection molded parts. The polyester powder contained 6 pg/g and 2 pg/g for 232 Th and 238 U, respectively. These levels correspond to 25 and 25 μBq/kg radioactivity, respectively. Determinations on samples of PVDF powder were typically below 1 pg/g for 232 Th and 2 pg/g for 238 U, corresponding to 4 and 25 μBq/kg radioactivity, respectively. The use of low mass ULB EF-Cu boats for dry ashing successfully overcame the problem of crucible-generated contaminants in the analysis; absolute detection limits, calculated as 3 × standard deviation of the process blanks, were typically 20-100 fg within a sample set. Complete dissolution of the ash and low mass boat provided high tracer recoveries and provides a convincing method to recover both the tracer and sample isotopes when full equilibration of tracer isotopes with sample isotopes is not possible prior to beginning chemical sample processing on solids.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arnquist, Isaac J.; Hoppe, Eric J.; Bliss, Mary
A rapid new method for determining the U and Th mass concentrations in high radiopurity plastics is described, consisting of 1) dry ashing the plastic sample and tracers in low mass crucibles made of ultra low background electroformed copper (ULB EF-Cu) foil cut and folded into boats, 2) dissolving both the ash and the boat in acid, 3) performing a column separation to remove copper, and 4) determining the elements of interest by isotope dilution mass spectrometry. This method was demonstrated on both unfluorinated and fluorinated plastics, demonstrating high tracer recoveries and detection limits to pg/g (i.e., parts per trillion)more » levels or below, corresponding to μBq/kg of material. Samples of biomedical polyester (Max-Prene® 955) and a fluoropolymer (polyvinylidene fluoride, PVDF) were analyzed in powder raw material forms as well as solids in the form of pellets or injection molded parts. The polyester powder contained 6 pg/g and 2 pg/g for Th and U respectively. These levels correspond to 25 and 25 μBq/kg radioactivity, respectively. Determinations on samples of PVDF powder were typically below 1 pg/g for Th and 2 pg/g for U, corresponding to 4 and 25 μBq/kg radioactivity, respectively. The use of low mass ULB EF-Cu boats for dry ashing successfully overcame the problem of crucible-generated contaminants in the analysis; absolute detection limits, calculated as 3 × standard deviation of the process blanks, were typically 20-100 fg within a sample set. Complete dissolution of the ash and low mass boat provided high tracer recoveries, and provides a convincing method to recover both the tracer and sample isotopes when full equilibration of tracer isotopes with sample isotopes is not possible prior to beginning chemical sample processing on solids.« less
The peculiar optical-UV X-ray spectra of the X-ray weak quasar PG 0043+039
NASA Astrophysics Data System (ADS)
Kollatschny, W.; Schartel, N.; Zetzl, M.; Santos-Lleó, M.; Rodríguez-Pascual, P. M.; Ballo, L.; Talavera, A.
2016-01-01
Context. The object PG 0043+039 has been identified as a broad absorption line (BAL) quasar based on its UV spectra. However, this optical luminous quasar has not been detected before in deep X-ray observations, making it the most extreme X-ray weak quasar known today. Aims: This study aims to detect PG 0043+039 in a deep X-ray exposure. The question is what causes the extreme X-ray weakness of PG 0043+039? Does PG 0043+039 show other spectral or continuum peculiarities? Methods: We took simultaneous deep X-ray spectra with XMM-Newton, far-ultraviolet (FUV) spectra with the Hubble Space Telescope (HST), and optical spectra of PG 0043+039 with the Hobby-Eberly Telescope (HET) and Southern African Large Telescope (SALT) in July, 2013. Results: We have detected PG 0043+039 in our X-ray exposure taken in 2013. We presented our first results in a separate paper (Kollatschny et al. 2015). PG 0043+039 shows an extreme αox gradient (αox = -2.37). Furthermore, we were able to verify an X-ray flux of this source in a reanalysis of the X-ray data taken in 2005. At that time, it was fainter by a factor of 3.8 ±0.9 with αox = -2.55. The X-ray spectrum is compatible with a normal quasar power-law spectrum (Γ = 1.70-0.45+0.57) with moderate intrinsic absorption (NH = 5.5-3.9+6.9 × 1021 cm-2) and reflection. The UV/optical flux of PG 0043+039 has increased by a factor of 1.8 compared to spectra taken in the years 1990-1991. The FUV spectrum is highly peculiar and dominated by broad bumps besides Lyα. There is no detectable Lyman edge associated with the BAL absorbing gas seen in the CIV line. PG 0043+039 shows a maximum in the overall continuum flux at around λ ≈ 2500 Å in contrast to most other AGN where the maximum is found at shorter wavelengths. All the above is compatible with an intrinsically X-ray weak quasar, rather than an absorbed X-ray emission. Besides strong FeII multiplets and broad Balmer and HeI lines in the optical band we only detect a narrow [O II]λ3727 emission line and a BAL system in the CaH λ3968, CaK λ3934 lines (blueshifted by 4900 km s-1) and in the He I λ3889 line (blueshifted by 5600 km s-1). Based on observations obtained with XMM-Newton, the Hubble Space Telescope (HST), Southern African Large Telescope (SALT), and Hobby-Eberly Telescope (HET).
Multicentury changes in ocean and land contributions to the climate-carbon feedback
DOE Office of Scientific and Technical Information (OSTI.GOV)
Randerson, J. T.; Lindsay, K.; Munoz, E.
Improved constraints on carbon cycle responses to climate change are needed to inform mitigation policy, yet our understanding of how these responses may evolve after 2100 remains highly uncertain. Using the Community Earth System Model (v1.0), we quantified climate-carbon feedbacks from 1850 to 2300 for the Representative Concentration Pathway 8.5 and its extension. In three simulations, land and ocean biogeochemical processes experienced the same trajectory of increasing atmospheric CO 2. Each simulation had a different degree of radiative coupling for CO 2 and other greenhouse gases and aerosols, enabling diagnosis of feedbacks. In a fully coupled simulation, global mean surfacemore » air temperature increased by 9.3 K from 1850 to 2300, with 4.4 K of this warming occurring after 2100. Excluding CO 2, warming from other greenhouse gases and aerosols was 1.6 K by 2300, near a 2 K target needed to avoid dangerous anthropogenic interference with the climate system. Ocean contributions to the climate-carbon feedback increased considerably over time and exceeded contributions from land after 2100. The sensitivity of ocean carbon to climate change was found to be proportional to changes in ocean heat content, as a consequence of this heat modifying transport pathways for anthropogenic CO 2 inflow and solubility of dissolved inorganic carbon. By 2300, climate change reduced cumulative ocean uptake by 330 Pg C, from 1410 Pg C to 1080 Pg C. Land fluxes similarly diverged over time, with climate change reducing stocks by 232 Pg C. Regional influence of climate change on carbon stocks was largest in the North Atlantic Ocean and tropical forests of South America. Our analysis suggests that after 2100, oceans may become as important as terrestrial ecosystems in regulating the magnitude of the climate-carbon feedback.« less
Multicentury changes in ocean and land contributions to the climate-carbon feedback
NASA Astrophysics Data System (ADS)
Randerson, J. T.; Lindsay, K.; Munoz, E.; Fu, W.; Moore, J. K.; Hoffman, F. M.; Mahowald, N. M.; Doney, S. C.
2015-06-01
Improved constraints on carbon cycle responses to climate change are needed to inform mitigation policy, yet our understanding of how these responses may evolve after 2100 remains highly uncertain. Using the Community Earth System Model (v1.0), we quantified climate-carbon feedbacks from 1850 to 2300 for the Representative Concentration Pathway 8.5 and its extension. In three simulations, land and ocean biogeochemical processes experienced the same trajectory of increasing atmospheric CO2. Each simulation had a different degree of radiative coupling for CO2 and other greenhouse gases and aerosols, enabling diagnosis of feedbacks. In a fully coupled simulation, global mean surface air temperature increased by 9.3 K from 1850 to 2300, with 4.4 K of this warming occurring after 2100. Excluding CO2, warming from other greenhouse gases and aerosols was 1.6 K by 2300, near a 2 K target needed to avoid dangerous anthropogenic interference with the climate system. Ocean contributions to the climate-carbon feedback increased considerably over time and exceeded contributions from land after 2100. The sensitivity of ocean carbon to climate change was found to be proportional to changes in ocean heat content, as a consequence of this heat modifying transport pathways for anthropogenic CO2 inflow and solubility of dissolved inorganic carbon. By 2300, climate change reduced cumulative ocean uptake by 330 Pg C, from 1410 Pg C to 1080 Pg C. Land fluxes similarly diverged over time, with climate change reducing stocks by 232 Pg C. Regional influence of climate change on carbon stocks was largest in the North Atlantic Ocean and tropical forests of South America. Our analysis suggests that after 2100, oceans may become as important as terrestrial ecosystems in regulating the magnitude of the climate-carbon feedback.
Atmospheric inversion of the surface CO2 flux with 13CO2 constraint
NASA Astrophysics Data System (ADS)
Chen, J. M.; Mo, G.; Deng, F.
2013-10-01
Observations of 13CO2 at 73 sites compiled in the GLOBALVIEW database are used for an additional constraint in a global atmospheric inversion of the surface CO2 flux using CO2 observations at 210 sites for the 2002-2004 period for 39 land regions and 11 ocean regions. This constraint is implemented using the 13CO2/CO2 flux ratio modeled with a terrestrial ecosystem model and an ocean model. These models simulate 13CO2 discrimination rates of terrestrial photosynthesis and respiration and ocean-atmosphere diffusion processes. In both models, the 13CO2 disequilibrium between fluxes to and from the atmosphere is considered due to the historical change in atmospheric 13CO2 concentration. For the 2002-2004 period, the 13CO2 constraint on the inversion increases the total land carbon sink from 3.40 to 3.70 Pg C yr-1 and decreases the total oceanic carbon sink from 1.48 to 1.12 Pg C yr-1. The largest changes occur in tropical areas: a considerable decrease in the carbon source in the Amazon forest, and this decrease is mostly compensated by increases in the ocean region immediately west of the Amazon and the southeast Asian land region. Our further investigation through different treatments of the 13CO2/CO2 flux ratio used in the inversion suggests that variable spatial distributions of the 13CO2 isotopic discrimination rate simulated by the models over land and ocean have considerable impacts on the spatial distribution of the inverted CO2 flux over land and the inversion results are not sensitive to errors in the estimated disequilibria over land and ocean.
Xu, Guilin; Chi, Yu; Li, Lu; Liu, Shouhua; Kan, Xianwen
2015-06-15
A novel imprinted sol-gel electrochemical sensor for the determination of propyl gallate (PG) was developed based on a composite of graphene and single walled carbon nanotubes (GR-SWCNTs). It was fabricated by stepwise modifying GR-SWCNTs and molecularly imprinted polymers and stored in 0.10 mol L(-1) phosphate buffer solution pH 6.0, which endowed the sensor good sensitivity and selective recognition towards template molecules. The morphology and specific adsorption capacity of the sensor was characterized by scanning electron microscope and electrochemical methods, respectively. Under the optimized conditions, a linear range of the sensor to PG was 8.0 × 10(-8)-2.6 × 10(-3)mo lL(-1) with a limit of detection of 5.0 × 10(-8)mol L(-1) (S/N=3). The sensor exhibited specificity and selectivity towards template molecules as well as excellent reproducibility, regeneration and stability. Furthermore, the sensor could be applied to determine PG in edible oils, instant noodles and cookies with satisfactory results. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tomassen, Monic M M; Barrett, Diane M; van der Valk, Henry C P M; Woltering, Ernst J
2007-01-01
An important aspect of the ripening process of tomato fruit is softening. Softening is accompanied by hydrolysis of the pectin in the cell wall by pectinases, causing loss of cell adhesion in the middle lamella. One of the most significant pectin-degrading enzymes is polygalacturonase (PG). Previous reports have shown that PG in tomato may exist in different forms (PG1, PG2a, PG2b, and PGx) commonly referred to as PG isoenzymes. The gene product PG2 is differentially glycosylated and is thought to associate with other proteins to form PG1 and PGx. This association is thought to modulate its pectin-degrading activity in planta. An 8 kDa protein that is part of the tomato PG1 multiprotein complex has been isolated, purified, and functionally characterized. This protein, designated 'activator' (ACT), belongs to the class of non-specific lipid transfer proteins (nsLTPs). ACT is capable of 'converting' the gene product PG2 into a more active and heat-stable form, which increases PG-mediated pectin degradation in vitro and stimulates PG-mediated tissue breakdown in planta. This finding suggests a new, not previously identified, function for nsLTPs in the modification of hydrolytic enzyme activity. It is proposed that ACT plays a role in the modulation of PG activity during tomato fruit softening.
Custodero, C; Mankowski, R T; Lee, S A; Chen, Z; Wu, S; Manini, T M; Hincapie Echeverri, J; Sabbà, C; Beavers, D P; Cauley, J A; Espeland, M A; Fielding, R A; Kritchevsky, S B; Liu, C K; McDermott, M M; Miller, M E; Tracy, R P; Newman, A B; Ambrosius, W T; Pahor, M; Anton, S D
2018-05-25
Growing evidence suggests chronic low-grade inflammation (LGI) as a possible mechanism underlying the aging process. Some biological and pharmaceutical compounds may reduce systemic inflammation and potentially avert functional decline occurring with aging. The aim of the present meta-analysis was to examine the association of pre-selected interventions on two established biomarkers of inflammation, interleukin-6 (IL-6), and C-reactive protein (CRP) in middle-age and older adults with chronic LGI. We reviewed the literature on potential anti-inflammatory compounds, selecting them based on safety, tolerability, acceptability, innovation, affordability, and evidence from randomized controlled trials. Six compounds met all five inclusion criteria for our systematic review and meta-analysis: angiotensin II receptor blockers (ARBs), metformin, omega-3, probiotics, resveratrol and vitamin D. We searched in MEDLINE, PubMed and EMBASE database until January 2017. A total of 49 articles fulfilled the selection criteria. Effect size of each study and pooled effect size for each compound were measured by the standardized mean difference. I 2 was computed to measure heterogeneity of effects across studies. The following compounds showed a significant small to large effect in reducing IL-6 levels: probiotics (-0.68 pg/ml), ARBs (-0.37 pg/ml) and omega-3 (-0.19 pg/ml). For CRP, a significant small to medium effect was observed with probiotics (-0.43 mg/L), ARBs (-0.2 mg/L), omega-3 (-0.17 mg/L) and metformin (-0.16 mg/L). Resveratrol and vitamin D were not associated with any significant reductions in either biomarker. These results suggest that nutritional and pharmaceutical compounds can significantly reduce established biomarkers of systemic inflammation in middle-age and older adults. The findings should be interpreted with caution, however, due to the evidence of heterogeneity across the studies. Copyright © 2018 Elsevier B.V. All rights reserved.
Plucinski, Mateusz M; Rogier, Eric; Dimbu, Pedro Rafael; Fortes, Filomeno; Halsey, Eric S; Aidoo, Michael
2017-10-01
Most malaria testing is by rapid diagnostic tests (RDTs) that detect Plasmodium falciparum histidine-rich protein 2 (HRP2). Recently, several RDT manufacturers have developed highly sensitive RDTs (hsRDTs), promising a limit of detection (LOD) orders of magnitude lower than conventional RDTs. To model the added utility of hsRDTs, HRP2 concentration in Angolan outpatients was measured quantitatively using an ultrasensitive bead-based assay. The distribution of HRP2 concentration was bimodal in both afebrile and febrile patients. The conventional RDT was able to detect 81% of all HRP2-positive febrile patients and 52-77% of HRP2-positive afebrile patients. The added utility of hsRDTs was estimated to be greater in afebrile patients, where an hsRDT with a LOD of 200 pg/mL would detect an additional 50-60% of HRP2-positive persons compared with a conventional RDT with a LOD of 3,000 pg/mL. In febrile patients, the hsRDT would detect an additional 10-20% of cases. Conventional RDTs already capture the vast majority of symptomatic HRP2-positive individuals, and hsRDTs would have to reach a sufficiently low LOD approaching 200 pg/mL to provide added utility in identifying HRP2-positive, asymptomatic individuals.
Iron Abundance in the Prototype PG 1159 Star, GW Vir Pulsator PG 1159-035, and Related Objects
NASA Technical Reports Server (NTRS)
Werner, K.; Rauch, T.; Kruk, J. W.; Kurucz, R. L.
2011-01-01
We performed an iron abundance determination of the hot, hydrogen deficient post-AGB star PG 1159-035. which is the prototype of the PG 1159 spectral class and the GW Vir pulsators, and of two related objects (PG 1520+525, PG 1144+005), based on the first detection of Fe VIII lines in stellar photospheres. In another PG 1159 star. PG 1424+535. we detect Fe VII lines. In all four stars, each within T(sub eff) = 110,000-150,000 K, we find a solar iron abundance. This result agrees with our recent abundance analysis of the hottest PG 1159 stars (T(sub eff) = 150,000-200,000 K) that exhibit Fe x lines. On the whole, we find that the PG 1159 stars are not significantly iron deficient, in contrast to previous notions.
NASA Astrophysics Data System (ADS)
Bao, Yongchao; Chen, Kezheng
2018-04-01
The novel BiOBr/reduced graphene oxide/protonated g-C3N4 (BiOBr/RGO/pg-C3N4) composites were successfully synthesized by using a facile solvothermal synthesis method. The structure, morphology, optical and electronic properties were explored by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DRS), and photoelectrochemical measurement. The photocatalytic activities of as-synthesized samples were evaluated by the degradation of Rhodamine B (Rh B) and tetracycline hydrochloride (TC) aqueous solution under visible light irradiation (λ > 420nm). Compared with BiOBr, protonated g-C3N4 (pg-C3N4), BiOBr/pg-C3N4 and RGO/pg-C3N4, BiOBr/RGO/pg-C3N4 composites exhibited higher photocatalytic activity. The total organic carbon (TOC) removal ratios of Rh B and TC over 10% BiOBr/RGO/pg-C3N4 were 88% and 59%, respectively. The excellent photcatalytic performance was investigated by photoluminescence spectroscopy (PL), the radical quenching and electron spin resonance experiments. A Z-scheme charge transfer mechanism was proposed, in which RGO acted as an electron transfer mediator. It was worth pointing out that the closely contacted two-dimensional interface among the BiOBr, the RGO and pg-C3N4 promoted the separation and transfer of photo-generated charge carriers, and thus enhanced the photocatalytic efficiency.
NASA Astrophysics Data System (ADS)
Devoino, O. G.; Feldshtein, E. É.; Kardapolova, M. A.; Lutsko, N. I.
2017-03-01
Some parameters of laser surfacing of self-fluxing nickel alloy PG-12N-01 are considered. Different structures containing a low-melting γ-Ni - Ni3B eutectic and a γ-Ni - Cr3C2 eutectic that crystallizes at a higher temperature and forms the strength skeleton of the coating may form depending on the rate of the surfacing. The effect of the rate of the surfacing on the wear resistance of the coating and on the coefficients of dry friction are determined.
Mechanisms of gastroprotection.
Konturek, S J
1990-01-01
Gastric mucosa is constantly exposed to various irritants, but it usually maintains its integrity owing to several lines of defense, including mucus-alkaline secretion, mucosal hydrophobicity, rich mucosal blood flow, stabilization of tissue lysosomes, maintenance of mucosal sulfhydryls, and rapid proliferation and renewal of mucosal cells. Prostaglandins (PG) inhibit experimental gastric mucosal damage and ulcerations induced by a wide variety of agents, hence PG have been proposed to contribute to the overall protective process by activation of various mucosal defence lines--particularly by prevention of vasocongestion, ischemia, and deep hemorrhagic necrosis. The relation between tissue PG generation and mucosal protection does not appear to be closely related, and probably only minute amounts of PG are required to maintain mucosal integrity. In contrast to PG, other products of arachidonate metabolism, such as TxA2, LTC4 or LTD4, and the related lipid, platelet-activating factor, appear to mediate mucosal damage mainly by the disturbance in mucosal microcirculation and tissue ischemia. Gastroprotection can be achieved by stimulation of mucosal biosynthesis of protective PG or by the inhibition of the release or action of the proulcerogenic arachidonate metabolites. Certain natural substances, such as sulfhydryls, epidermal growth factor, or polyamines, protect the mucosa via a PG-independent mechanism, probably by enhancing the tissue repair processes.(ABSTRACT TRUNCATED AT 250 WORDS)
John, William S; Banala, Ashwini K; Newman, Amy H; Nader, Michael A
2015-04-01
The dopamine (DA) D2 and D3 receptors have been associated with cocaine abuse. A recent study with the D3 receptor (D3R) partial agonist PG619 found that it attenuated cocaine-induced reinstatement and the D2-like receptor antagonist buspirone has shown positive outcomes in two studies of cocaine abuse in monkeys. However, a recent clinical trial indicated that buspirone did not improve abstinence in treatment-seeking cocaine abusers. The objective of the study was to examine PG619 and buspirone under a food-drug choice paradigm in order to better model the clinical findings. In addition, we extended the characterization of both compounds to include methamphetamine (MA) self-administration (SA). Six adult male rhesus monkeys were trained to respond under a concurrent food (1.0-g pellets) and drug (0.01-0.3 mg/kg/injection cocaine or MA) choice paradigm in which complete SA dose-response curves were determined each session (N = 3/group). Monkeys received 5 days of treatment with either PG619 (0.1-3.0 mg/kg, i.v.) or buspirone (0.01-1.0 mg/kg, i.m.). In a follow-up study, the SA doses were reduced (0.003-0.1 mg/kg/injection) to increase reinforcement frequency and buspirone was retested. PG619 did not affect cocaine or MA choice, while buspirone increased low-dose cocaine choice. Changing the SA doses increased the number of reinforcers received each session, but buspirone did not decrease drug choice. Consistent with clinical findings, these results do not support the use of buspirone for psychostimulant abuse and suggest that food-drug choice paradigms may have greater predictive validity than the use of other schedules of reinforcement.
In-Flight Annealing of Magnetic Nanoparticles, Produced by the Particle Gun Technique
NASA Astrophysics Data System (ADS)
Stoyanov, S.; Skumryev, V.; Zhang, Y.; Huang, Y.; Hadjipanayis, G. C.
2003-03-01
The need of post annealing of nanocomposite structures aimed to form nanoparticles or to obtain a desired crystal structure often results in particles growth and/or a harmful alloying with the matrix material. In this study, we present a new technique to perform an in situ phase transformation of particles produced by the gas condensation process in a Particle Gun (PG). Particles are heat treated during their flight from the PG to the substrate, by absorption of light in a specially designed Heating Stage (HS), placed on the top of the PG. The total power of the light sources used is 2 kWatt. A simple model for the thermodynamic conditions in a single particle during the annealing process is developed. It is shown that the temperature of the particle depends on the light power and the size of the particle and can easily reach the required annealing values of 400 to 900^oC in a millisecond time scale. The versatility of this technique is demonstrated on the fabrication of high anisotropy FePt and SmCo particles, embedded in a carbon matrix. Work supported by NSF DMR9972035
ONIX results: Comparison of grid geometry (BATMAN - ELISE - flat grid)
NASA Astrophysics Data System (ADS)
Revel, Adrien; Mochalskyy, Serhiy; Wünderlich, Dirk; Fantz, Ursel; Minea, Tiberiu
2017-08-01
The 3D PIC-MCC code ONIX is dedicated to the modelling of negative hydrogen or deuterium ion extraction and the co-extracted electrons from the plasma in radio-frequency driven sources. The extraction process highly depends on the plasma characteristics close to the plasma grid where it is difficult to obtain experimental data. ONIX brings valuable insights on the plasma behavior in this area. In the code, the numerical treatment of the boundaries have been improved in order to describe with more accuracy the potential and the electric field in this vicinity. The computation time has been reduced by a factor of 2 and the parallelization efficiency has been highly improved. The influence of the magnetic field in BATMAN on the plasma behaviour has been investigated by comparing two different configurations of the magnet bars producing the filter field (internal magnets: x = 3 cm; external magnets: x = 9 cm). A flat grid geometry for the PG instead of the usual conical grid geometry has been studied to evaluate its impact on the extracted current, especially for the negative ions emitted from the surface of the PG. Finally, the ONIX code has been used for the first 3D PIC calculations ever performed for the ELISE experiment.
Ślusarz, Rafał; Szulc, Monika; Madaj, Janusz
2014-05-07
Proper understanding of the mechanisms of binding to Gram-positive bacteria cell wall layers-especially to the peptidoglycan (PG) layer, seems to be crucial for proper development of new drug candidates which are effective against these bacteria. In this work we have constructed two different models of the Gram-positive bacteria PG layer: the layered and the scaffold models. PG conformational changes during geometry optimization, models relaxation, and molecular dynamics were described and discussed. We have found that the border surface of both PG layer models differs from the surface located away from the edge of models and the chains formed by disaccharide units prefer helix-like conformation. This curling of PG chains significantly affects the shape of antibiotic-accessible surface and the process is thus crucial for new drug development. Glycopeptide antibiotics effective against Gram-positive bacteria, such as vancomycin and its semisynthetic derivatives-oritavancin and telavancin, bind to d-alanyl-d-alanine stem termini on the peptidoglycan precursors of the cell wall. This binding inhibits cross-linking between the peptides and subsequently prevents cell wall synthesis. In this study some of the aspects of conformational freedom of vancomycin and restrictions from the modifications of vancomycin structure introduced into oritavancin and telavancin and five other vancomycin derivatives (with addition of 2-acetamido-2-deoxy-β-d-galactopyranosylamine, 2-acetamido-2-deoxy-β-d-glucopyranosylamine, 1-amine-1-deoxy-d-glucitol, 2-amino-2-deoxy-d-galactitol, or 2-amino-2-deoxy-d-glucitol to the C-terminal amino acid group in the vancomycin) are presented and discussed. The resulting molecular dynamics trajectories, root mean square deviation changes of aglycon and saccharide moieties as well as a comparative study of possible interactions with cyclic and chain forms of modified groups have been carried out, measured, and analyzed. Energetically advantageous conformations show close similarity to the structures known from the experimental data, but the diversity of others suggest very high conformational freedom of all modeled antibiotics and vancomycin derivatives. Alditol derivatives move closer to the peptidoglycan chain more easily but they also form intramolecular interactions more frequently than their homologous cyclic forms. One of the proposed derivatives seems to be a promising agent which is efficient in treatment of infections caused by Gram-positive bacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hoyer, D.; Rauch, T.; Werner, K.; Kruk, J. W.
2018-04-01
The metal abundances in the atmospheres of hot white dwarfs (WDs) entering the cooling sequence are determined by the preceding Asymptotic Giant Branch (AGB) evolutionary phase and, subsequently, by the onset of gravitational settling and radiative levitation. In this paper, we investigate three hot He-rich WDs, which are believed to result from a late He-shell flash. During such a flash, the He-rich intershell matter is dredged up and dominates the surface chemistry. Hence, in contrast to the usual H-rich WDs, their spectra allow direct access to s-process element abundances in the intershell that were synthesized during the AGB stage. In order to look for trans-iron group elements (atomic number Z > 29), we performed a non-local thermodynamic equilibrium model atmosphere analysis of new ultraviolet spectra taken with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. One of our program stars is of PG 1159 spectral type; this star, PG 1707+427, has effective temperature Teff = 85 000 K, and surface gravity logg = 7.5. The two other stars are DO white dwarfs: WD 0111+002 has Teff = 58 000 K and log g = 7.7, and PG 0109+111 has Teff = 70 000 K and log g = 8.0. These stars trace the onset of element diffusion during early WD evolution. While zinc is the only trans-iron element we could detect in the PG 1159 star, both DOs exhibit lines from Zn, Ga, Ge, Se; one additionally exhibits lines from Sr, Sn, Te, and I and the other from As. Generally, the trans-iron elements are very abundant in the DOs, meaning that radiative levitation must be acting. Most extreme is the almost six orders of magnitude oversolar abundance of tellurium in PG 0109+111. In terms of mass fraction, it is the most abundant metal in the atmosphere. The two DOs join the hitherto unique hot DO RE 0503-289, in which 14 trans-iron elements had even been identified. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26666.Based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer.
Variation in nuclear DNA content in Malus species and cultivated apples.
Tatum, Tatiana C; Stepanovic, Svetlana; Biradar, D P; Rayburn, A Lane; Korban, Schuyler S
2005-10-01
The nuclear DNA content for a group of 40 Malus species and hybrids has been estimated using flow cytometry. Estimates of nuclear DNA content for this germplasm collection range from 1.45 pg for Malus fusca (diploid) to 2.57 pg for Malus ioensis (triploid). Among diploids, the nuclear (2C) DNA ranges from 1.45 pg for M. fusca to 1.68 pg for Malus transitoria. Among triploids, the nuclear (3C) DNA content ranges from 2.37 pg / 3C for Malus sikkimensis to 2.57 pg / 3C for M. ioensis. Given the complexity of the apple genome and its suggested allopolyploid origin, the results obtained in this study confirm earlier reports that polyploids can easily withstand the loss of a certain amount of DNA, and that there is a slight tendency towards diminished haploid nuclear DNA content with increased polyploidy.
Polarization gating of high harmonic generation in the water window
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Jie; Ren, Xiaoming; Yin, Yanchun
2016-06-06
We implement the polarization gating (PG) technique with a two-cycle, 1.7 μm driving field to generate an attosecond supercontinuum extending to the water window spectral region. The ellipticity dependence of the high harmonic yield over a photon energy range much broader than previous work is measured and compared with a semi-classical model. When PG is applied, the carrier-envelope phase (CEP) is swept to study its influence on the continuum generation. PG with one-cycle (5.7 fs) and two-cycle (11.3 fs) delay are tested, and both give continuous spectra spanning from 50 to 450 eV under certain CEP values, strongly indicating the generation ofmore » isolated attosecond pulses in the water window region.« less
Kowalczuk, Joanna; Bielejewski, Michał; Lapiński, Andrzej; Luboradzki, Roman; Tritt-Goc, Jadwiga
2014-04-10
Organogels are soft materials consisting of low-molecular-mass gelators (LMOGs) self-assembled through noncovalent interactions into 3D structures, in which free spaces are filled by organic solvents. 4,6,4',6'-O-terephthylidene-bis(methyl-α-d-glucopyranoside) (1) is found to be a new LMOG. It gelatinizes only a limited number of solvents. Here, the gels of 1 with ethylene glycol (EG) and 1,3-propanediol (PG) are investigated with FT-IR, Raman, and UV-vis spectroscopies, the NMR relaxometry and diffusometry methods, and microscopic observation. The chemical structures of both solvents are closely related, but the variety of physical characteristics of the gels is large. The 1/PG gels are thermally more stable compared to 1/EG gels. The types of aggregates are most likely the H- and J-type in 1/EG gels and the J-type in 1/PG gels. Different microstructures are observed: bundles of crossing fibers for 1/EG and a honeycomb-like matrix for 1/PG gels. The diffusivity of the EG solvent in gels with 1 behaves as expected, decreasing with increasing gelator concentration, whereas the opposite behavior is observed for the PG solvent. This is a most fascinating result. To explain the diffusion enhancement, we suggest that a dynamic hydrogen bonding network of PG solvent in gel matrixes is disrupted due to solvent-gelator interaction. The direct proof of this interaction is given by the observed low frequency dispersion of the spin-lattice relaxation time of solvents in the gel matrixes.
Lohscheider, Jens N; Río Bártulos, Carolina
2016-08-01
Plastoglobules (PG) are lipophilic droplets attached to thylakoid membranes in higher plants and green algae and are implicated in prenyl lipid biosynthesis. They might also represent a central hub for integration of plastid signals under stress and therefore the adaptation of the thylakoid membrane under such conditions. In Arabidopsis thaliana, PG contain around 30 specific proteins of which Fibrillins (FBN) and Activity of bc1 complex kinases (ABC1K) represent the majority with respect to both number and protein mass. However, nothing is known about the presence of PG in most algal species, which are responsible for about 50% of global primary production. Therefore, we searched the genomes of publicly available algal genomes for components of PG and the associated functional network in order to predict their presence and potential evolutionary conservation of physiological functions. We could identify homologous sequences for core components of PG, like FBN and ABC1K, in most investigated algal species. Furthermore, proteins at central and interesting positions within the PG functional coexpression network were identified. Phylogenetic sequence analysis revealed diversity within FBN and ABC1K sequences among algal species with complex plastids of the red lineage and large differences compared with green lineage species. Two types of FBN were detected that differ in their isoelectric point which seems to correlate with subcellular localization. Subgroups of FBN were shared between many investigated species and modeling of their 3D-structure implied a conserved structure. FBN and ABC1K are essential structural and functional components of PG. Their occurrence in investigated algal species suggests presence of PG therein and functions in prenyl lipid metabolism and adaptation of the thylakoid membrane that are conserved during evolution. Copyright © 2016 Elsevier B.V. All rights reserved.
Chatzinasiou, Foteini; Polymeros, Dimitrios; Panagiotou, Maro; Theodoropoulos, Konstadinos; Rigopoulos, Dimitrios
2016-04-01
Pyoderma gangrenosum (PG) is a rare ulcerative skin disease, part of the spectrum of neutrophilic and auto-inflammatory dermatoses. Its pathogenesis is unknown, although immune pathways have been implicated. Lesion biopsies show a predominantly neutrophilic infiltrate. The incidence of PG is uncertain, but it is estimated to be 3-10 per million per year, occurring at any age but most commonly between 20 and 50 years with a possible slightly higher incidence in women. Approximately 50% of patients with PG also have another disease associated with PG. The most common is inflammatory bowel disease (IBD), particularly Crohn's and ulcerative colitis (UC). Local treatment may be sufficient for mild cases, while for severe cases systemic immunosuppressants are the mainstay (1,2). We report the case of a patient with bullous PG and UC successfully treated with infliximab and azathioprine. A 32-year-old male Caucasian patient presented with painful violaceous vesicles and enlarging bullae of various sizes and with acute onset, located on the trunk and bilaterally on both the lower and the upper extremities. Lesions on the trunk were composed of hemorrhagic pustules with a surrounding erythematous overhanging border. Some of the lesions had undergone central necrosis and ulceration (Figure 1, a-d). The patient reported of the lesions had appeared one week ago, simultaneously with the exacerbation of a known inflammatory bowel disease with hemorrhagic mucoid diarrhea and fever of up to 38.5°C. The patient's medical history included UC affecting the whole colon (pancolitis), diagnosed 5 months prior to the onset of the epidermal lesions, for which the patient was receiving treatment with oral prednisolone 10 mg/day and mesalazine granules. Blood tests showed severe anemia, leukocytosis, and increased inflammatory markers (C-reactive protein, erythrocyte sedimentation rate). Antinuclear antibodies (ANA), anti-double stranded DNA (anti-dsDNA) andtibodies, antineutrophil cytoplasmic antibodies (cANCA), perinuclear neutrophil antibodies (p-ANCA), antiphospholipid antibodies, and tumor markers were within normal limits. The patient was negative for cryoglobulins, viral hepatitis (B, C) and human immunodeficiency virus (HIV). Blood cultures were negative. Microscopy and cultures for mycobacteria and fungi gave negative results. Stool samples tested negative for infections agents. The Mantoux skin test was negative. Colonoscopy showed severe pancolitis, and biopsies from the rectum and sigmoid colon were consistent with chronic ulcerative colitis. Abdominal ultrasound and chest and abdominal X-rays did not result in significant findings. Because of severe anemia, the patient received 2 blood transfusions. The histopathologic examination carried out on the erythematous border of a lesion on the lower leg showed a neutrophilic infiltrate, confined to the dermis. On the basis of clinical findings, the diagnosis of PG was established. Topical wound care consisted of local wound care and a topical corticosteroid. Systemic therapy was initiated with 40 mg/day methylprednisolone for 7 days, 30 mg/day for 7 days, then 25 mg/day, and then tapered down further. The patient received an infusion of infliximab 7.5 mg/kg at weeks 0, 2, and 6 and every 8 weeks thereafter. After week 2, oral azathioprine 2.5 mg/kg daily was added to the treatment. The patient also received mesalazine tablets (2 g ×2/day) and mesalazine enema (1-2/day). The patient showed good response to treatment, with clinical remission of skin lesions. Lesions healed with characteristic thin, atrophic scars (Figure 2, a-d). At 7-month follow-up the patient was continuing with infusions of infliximab 7.5 mg/kg and azathioprine 2.5 mg/kg and was still in remission. We reported our experience with a case of generalized bullous pyoderma gangrenosum associated with ulcerative colitis. Generalized pyoderma gangrenosum is very rare. Bullous or atypical PG was first described by Perry and Winklemann in 1972 (1). Brunsting et al. coined the term pyoderma gangrenosum (PG) to describe a series of patients with recurrent ulcerations (3). The incidence of this disease is uncertain. Its pathogenesis is unknown, but an immunological background has been suggested. In approximately 50% of patients, an underlying immunological disease is present, commonly inflammatory bowel disease (IBD) (4-6). In larger series of patients with PG, approximately 50% present with a primary disorder. Ulcerative colitis is found in 10-15% of cases. Crohn's disease is associated with PG closed than UC. Less than 3% of patients with Crohn's disease or UC develop PG (6). PG is characterized by cutaneous ulcerations with mucopurulent or hemorrhagic exudate. It begins as an inflammatory pustule with a surrounding halo that enlarges and begins to ulcerate. These very painful ulcers present with undermined bluish borders with surrounding erythema. The lesions of PG most commonly occur on the legs, but they may occur anywhere on the body. The clinical picture of PG is very characteristic. Therefore the diagnosis of PG is based firstly on clinical signs and on the patient's history of underlying diseases and then supported by biopsy. PG has four distinctive clinical and histological variants. Some have morphological and histological features that overlap with other reactive neutrophilic skin conditions. There are no diagnostic serologic features (6,7). There is no evidence that the efficacy of treatment strategies for PG differs between IBD and non-IBD patients. For patients with a diffuse disease or rapidly progressive process, systemic treatment is essential. Immunosuppression is the mainstay of treatment. Traditionally, the most commonly used drugs with the best clinical experience are systemic corticosteroids. Corticosteroids have been considered as first line treatment (6,8). As reported by the European Crohn's and Colitis Organisation (ECCO) in 2008, an evidence-based consensus on the management of special situations in patients with ulcerative colitis, systemic corticosteroids are recommended (9). Treatment with corticosteroids (e.g. prednisolone 1-2 mg per kg/day or pulse therapy with 1 g of methylprednisolone) aims to prevent progression and rapidly stop inflammation (6). Additional mesalamine and corticosteroids may be effective in patients with bowel disease (10). In recent years, tumor necrosis alpha (TNF-α) inhibitors, such as infliximab and adalimumab, were reported to be effective for PG associated with IBD. These drugs block the biological activity of TNF-α, which effects regulatory T cells, restoring their capacity to inhibit cytokine production. The TNF-α inhibitors thus suppress the inflammatory processes that is involved in the pathogenesis of PG (11). Infliximab, a chimeric monoclonal antibody, is given by infusion at weeks 0, 2, and 6 and then every 8 weeks, usually at a dosage of 5 mg/kg. UC of patients with frequent disease relapse or those that are resistant or dependent on corticosteroids is often treated with purine antimetabolites, such as azathioprine (AZA) (10). AZA, a purine antimetabolite (2.5 mg per kg/day) is administered for its steroid-sparing effects. The response occurs after 2 to 4 weeks (6, 10). Infliximab can be combined with AZA. Patients with UC treated with infliximab plus AZA were more likely to achieve corticosteroid-free remission at 16 weeks than those receiving either monotherapy (10,12).
A joint global carbon inversion system using both CO2 and 13CO2 atmospheric concentration data
NASA Astrophysics Data System (ADS)
Chen, Jing M.; Mo, Gang; Deng, Feng
2017-03-01
Observations of 13CO2 at 73 sites compiled in the GLOBALVIEW database are used for an additional constraint in a global atmospheric inversion of the surface CO2 flux using CO2 observations at 210 sites (62 collocated with 13CO2 sites) for the 2002-2004 period for 39 land regions and 11 ocean regions. This constraint is implemented using prior CO2 fluxes estimated with a terrestrial ecosystem model and an ocean model. These models simulate 13CO2 discrimination rates of terrestrial photosynthesis and ocean-atmosphere diffusion processes. In both models, the 13CO2 disequilibrium between fluxes to and from the atmosphere is considered due to the historical change in atmospheric 13CO2 concentration. This joint inversion system using both13CO2 and CO2 observations is effectively a double deconvolution system with consideration of the spatial variations of isotopic discrimination and disequilibrium. Compared to the CO2-only inversion, this 13CO2 constraint on the inversion considerably reduces the total land carbon sink from 3.40 ± 0.84 to 2.53 ± 0.93 Pg C year-1 but increases the total oceanic carbon sink from 1.48 ± 0.40 to 2.36 ± 0.49 Pg C year-1. This constraint also changes the spatial distribution of the carbon sink. The largest sink increase occurs in the Amazon, while the largest source increases are in southern Africa, and Asia, where CO2 data are sparse. Through a case study, in which the spatial distribution of the annual 13CO2 discrimination rate over land is ignored by treating it as a constant at the global average of -14. 1 ‰, the spatial distribution of the inverted CO2 flux over land was found to be significantly modified (up to 15 % for some regions). The uncertainties in our disequilibrium flux estimation are 8.0 and 12.7 Pg C year-1 ‰ for land and ocean, respectively. These uncertainties induced the unpredictability of 0.47 and 0.54 Pg C year-1 in the inverted CO2 fluxes for land and ocean, respectively. Our joint inversion system is therefore useful for improving the partitioning between ocean and land sinks and the spatial distribution of the inverted carbon flux.
NASA Astrophysics Data System (ADS)
Parazoo, Nicholas C.; Koven, Charles D.; Lawrence, David M.; Romanovsky, Vladimir; Miller, Charles E.
2018-01-01
Thaw and release of permafrost carbon (C) due to climate change is likely to offset increased vegetation C uptake in northern high-latitude (NHL) terrestrial ecosystems. Models project that this permafrost C feedback may act as a slow leak, in which case detection and attribution of the feedback may be difficult. The formation of talik, a subsurface layer of perennially thawed soil, can accelerate permafrost degradation and soil respiration, ultimately shifting the C balance of permafrost-affected ecosystems from long-term C sinks to long-term C sources. It is imperative to understand and characterize mechanistic links between talik, permafrost thaw, and respiration of deep soil C to detect and quantify the permafrost C feedback. Here, we use the Community Land Model (CLM) version 4.5, a permafrost and biogeochemistry model, in comparison to long-term deep borehole data along North American and Siberian transects, to investigate thaw-driven C sources in NHL ( > 55° N) from 2000 to 2300. Widespread talik at depth is projected across most of the NHL permafrost region (14 million km2) by 2300, 6.2 million km2 of which is projected to become a long-term C source, emitting 10 Pg C by 2100, 50 Pg C by 2200, and 120 Pg C by 2300, with few signs of slowing. Roughly half of the projected C source region is in predominantly warm sub-Arctic permafrost following talik onset. This region emits only 20 Pg C by 2300, but the CLM4.5 estimate may be biased low by not accounting for deep C in yedoma. Accelerated decomposition of deep soil C following talik onset shifts the ecosystem C balance away from surface dominant processes (photosynthesis and litter respiration), but sink-to-source transition dates are delayed by 20-200 years by high ecosystem productivity, such that talik peaks early ( ˜ 2050s, although borehole data suggest sooner) and C source transition peaks late ( ˜ 2150-2200). The remaining C source region in cold northern Arctic permafrost, which shifts to a net source early (late 21st century), emits 5 times more C (95 Pg C) by 2300, and prior to talik formation due to the high decomposition rates of shallow, young C in organic-rich soils coupled with low productivity. Our results provide important clues signaling imminent talik onset and C source transition, including (1) late cold-season (January-February) soil warming at depth ( ˜ 2 m), (2) increasing cold-season emissions (November-April), and (3) enhanced respiration of deep, old C in warm permafrost and young, shallow C in organic-rich cold permafrost soils. Our results suggest a mosaic of processes that govern carbon source-to-sink transitions at high latitudes and emphasize the urgency of monitoring soil thermal profiles, organic C age and content, cold-season CO2 emissions, and atmospheric 14CO2 as key indicators of the permafrost C feedback.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rafique, Rashid; Zhao, Fang; de Jong, Rogier
The net primary productivity (NPP) is commonly used for understanding the dynamics of terrestrial ecosystems and their role in carbon cycle. We used a combination of the most recent NDVI and model–based NPP estimates (from five models of the TRENDY project) for the period 1982-2012, to study the role of terrestrial ecosystems in carbon cycle under the prevailing climate conditions. We found that 80% and 67% of the global land area showed positive NPP and NDVI values, respectively, for this period. The global NPP was estimated to be about 63 Pg C y -1, with an increase of 0.214 Pgmore » C y -1 y -1. Similarly, the global mean NDVI was estimated to be 0.33, with an increasing trend of 0.00041 y-1. The spatial patterns of NPP and NDVI demonstrated substantial variability, especially at the regional level, for most part of the globe. However, on temporal scale, both global NPP and NDVI showed a corresponding pattern of increase (decrease) for the duration of this study except for few years (e.g. 1990 and 1995-98). Generally, the Northern Hemisphere showed stronger NDVI and NPP increasing trends over time compared to the Southern Hemisphere; however, NDVI showed larger trends in Temperate regions while NPP showed larger trends in Boreal regions. Among the five models, the maximum and minimum NPP were produced by JULES (72.4 Pg C y -1) and LPJ (53.72 Pg C y -1) models, respectively. At latitudinal level, the NDVI and NPP ranges were ~0.035 y -1 to ~-0.016 y -1 and ~0.10 Pg C y -1 y -1 to ~-0.047 Pg C y -1 y -1, respectively. Overall, the results of this study suggest that the modeled NPP generally correspond to the NDVI trends in the temporal dimension. Lastly, the significant variability in spatial patterns of NPP and NDVI trends points to a need for research to understand the causes of these discrepancies between molded and observed ecosystem dynamics, and the carbon cycle.« less
Intestine-specific overexpression of IL-10 improves survival in polymicrobial sepsis
Rajan, Saju; Vyas, Dinesh; Clark, Andrew T; Woolsey, Cheryl A; Clark, Jessica A; Hotchkiss, Richard S; Buchman, Timothy G; Coopersmith, Craig M
2007-01-01
Targeted Interleukin (IL)-10 therapy improves survival in preclinical models of critical illness, and intestine-specific IL-10 decreases inflammation in models of chronic inflammatory disease. We therefore sought to determine whether intestine-specific overexpression of IL-10 would improve survival in sepsis. Transgenic mice that overexpress IL-10 in their gut epithelium (Fabpi-IL-10 mice) and wild type (WT) littermates (n=127) were subjected to cecal ligation and puncture with a 27-gauge needle. Seven-day survival was 45% in transgenic animals and 30% in WT animals (p≤0.05). Systemic levels of IL-10 were undetectable in both groups of animals under basal conditions and were elevated to a similar degree in septic animals, regardless of whether they expressed the transgene. Local parameters of injury including gut epithelial apoptosis, intestinal permeability, peritoneal lavage cytokines and stimulated cytokines from intraepithelial lymphocytes were similar between transgenic and wildtype mice. However, in stimulated splenocytes, pro-inflammatory cytokines MCP-1 (189 ± 43 pg/ml vs. 40 ± 8 pg/ml) and IL-6 (116 ± 28 pg/ml vs. 34 ± 9 pg/ml) were lower in Fabpi-IL-10 mice than WT littermates despite the intestine-specific nature of the transgene (p<0.05). Cytokine levels were similar in blood and bronchoalveolar lavage fluid between the two groups as were circulating LPS levels. Transgenic mice also had lower white blood cell counts, associated with lower absolute neutrophil counts (0.5 ± 0.1 103/mm3 vs. 1.0 ± 0.2 103/mm3, p<0.05). These results indicate that gut-specific overexpression of IL-10 improves survival in a murine model of sepsis, and interactions between the intestinal epithelium and the systemic immune system may play a role in conferring this survival advantage. PMID:17998890
Comparison the Serum STREM1 Levels Between Children with Upper and Lower UTI.
Ehsanipour, Fahime; Noorbakhsh, Samileh; Zarabi, Vida; Movahedi, Zahra; Rahimzadeh, Nahid
2017-01-01
Pyelonephritis is the most common and important infection among Iranian pediatric population. Differentiation between upper and lower Urinary Tract Infection (UTI) is often difficult based on clinical data. Therefore, definite diagnosis is helpful for choosing appropriate antibiotic and decision for hospital admission. The main purpose of this study was todetermine the diagnostic value of serum STREM-1 level in children suspicious to UTI and differentiation of upper UTI and lower UTI. This prospective cross sectional study (2010-2011) was performed to evaluate and compare the serum level of STREM- 1 (pg. /ml) in 36 diagnosed UTI patients (24 upper and 12 lower UTI) with 25 normal children (without UTI) in Rasoul Akram hospital, Tehran, Iran. The mean age of studied children was 3.64 years; 24 male and 37 female. Urinary analysis and urine culture were performed for all UTI cases and only the positive cultured cases with the same microorganism were enrolled in the study. Distinguishing the upper from lower UTI was done on the basis of clinical manifestation and laboratory tests and confirmed by Imaging studies (ultra sonography /or DMSA scan). Blood sampling was taken from all children and centrifuged .The level of STREM-1 (pg /ml) in all sera was determined by Enzyme immunoassay technique (Human TREM-1 immunoassay Sandwich test, Quantikine, R&D systems, Minneapolis; USA). Cut-off levels for STREM-1 were illustrated by ROC curve. The p<0.05 was considered as significant for differences between groups. The mean of STREM -1level had significant difference between overall cases of UTI (427.72pg/ml) and controls (124.24 pg. /ml; P =0.000) ; with cutoff point 111.5 pg./ml ; it had 83.3% sensitivity; and 60 % specificity to distinguish UTI from control. Serum STREM -1 level had no significantly difference between the upper and lower UTI (500pg/ml vs. 283 pg. /ml, P value=0.1) with cutoff point 132 pg./ml it had 83.3% sensitivity ; and 60 % specificity to distinguish upper UTI from lower UTI. Our study demonstrates that even low amount of serum STREM-1 (111.5 pg./ml) has 83.3% sensitivity ; and 60 % specificity to distinguish the UTI from normal cases (P value =0.000) but higher level (132 pg./ml) was needed for definite diagnosis (83.3% sensitivity; 60 % specificity) of upper and lower UTI. It is concluded that serum STREM-1 level test is a valuable tool for early diagnosis of the normal cases with false positive urine culture, or in highly suspicious upper UTI cases with false negative urine culture. Indeed higher titer of this biomarker could be helpful for discriminating the upper from lower UTI. Therefore adding this new biologic marker (STREM-1) to previous ones (CRP, PCT) is suggested to prevent the unnecessary hospital admission and empiric antibiotic therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Atmospheric concentrations of polybrominated diphenyl ethers at near-source sites.
Cahill, Thomas M; Groskova, Danka; Charles, M Judith; Sanborn, James R; Denison, Michael S; Baker, Lynton
2007-09-15
Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in air samples from near suspected sources, namely an indoors computer laboratory, indoors and outdoors at an electronics recycling facility, and outdoors at an automotive shredding and metal recycling facility. The results showed that (1) PBDE concentrations in the computer laboratorywere higherwith computers on compared with the computers off, (2) indoor concentrations at an electronics recycling facility were as high as 650,000 pg/m3 for decabromodiphenyl ether (PBDE 209), and (3) PBDE 209 concentrations were up to 1900 pg/m3 at the downwind fenceline at an automotive shredding/metal recycling facility. The inhalation exposure estimates for all the sites were typically below 110 pg/kg/day with the exception of the indoor air samples adjacent to the electronics shredding equipment, which gave exposure estimates upward of 40,000 pg/kg/day. Although there were elevated inhalation exposures at the three source sites, the exposure was not expected to cause adverse health effects based on the lowest reference dose (RfD) currently in the Integrated Risk Information System (IRIS), although these RfD values are currently being re-evaluated by the U.S. Environmental Protection Agency. More research is needed on the potential health effects of PBDEs.
Liu, Guangqing; Xue, Mengwei; Liu, Qinpu; Zhou, Yuming
2017-01-01
Water-soluble monomer APEG-PG-(OH)n were produced and the Structure of APEG-PG-(OH)5 were identified by 1 H-NMR. APEG-PG-(OH)n were copolymerized with maleic anhydride (MA) to synthesize no phosphate and nitrogen free calcium carbonate inhibitor MA/APEG-PG-(OH)n. The structure and thermal property of MA/APEG-PG-(OH)5 were characterized and measured by 1 H-NMR, GPC and TGA. The observation shows that the dosage and n value of MA/APEG-PG-(OH)n plays an important role on CaCO 3 inhibition. MA/APEG-PG-(OH)5 displays superior ability to inhibit the precipitation of calcium carbonate, with approximately 97% inhibition at a level of 8 mg/L. The effect on formation of CaCO 3 was investigated with combination of SEM and XRD analysis.
Liu, Guangqing; Xue, Mengwei; Liu, Qinpu; Zhou, Yuming
2017-01-01
Abstract Water-soluble monomer APEG-PG-(OH)n were produced and the Structure of APEG-PG-(OH)5 were identified by 1H-NMR. APEG-PG-(OH)n were copolymerized with maleic anhydride (MA) to synthesize no phosphate and nitrogen free calcium carbonate inhibitor MA/APEG-PG-(OH)n. The structure and thermal property of MA/APEG-PG-(OH)5 were characterized and measured by 1H-NMR, GPC and TGA. The observation shows that the dosage and n value of MA/APEG-PG-(OH)n plays an important role on CaCO3 inhibition. MA/APEG-PG-(OH)5 displays superior ability to inhibit the precipitation of calcium carbonate, with approximately 97% inhibition at a level of 8 mg/L. The effect on formation of CaCO3 was investigated with combination of SEM and XRD analysis. PMID:29491811
Public health assessment of dioxin-contaminated fish at former US airbase, Bien Hoa, Vietnam.
Durant, James T; Boivin, Thomas G; Pohl, Hana R; Sinks, Thomas H
2015-01-01
Ponds at the former US airbase at Ben Hoa, Vietnam are contaminated with Agent Orange. The ponds had been used for aquaculture, and in all likelihood, fish from those ponds have been sold to the public. We assessed human exposure to 2,3,7,8-tetrachloro-dibenzo-dioxin (2,3,7,8-TCDD) in fish samples from the ponds. For on-base tilapia, muscle concentrations 2,3,7,8-TCDD ranged from 1.4 to 32.7 pg/g. Fat concentrations ranged from 73.3 to 3990 pg/g. Estimated human exposure doses exceed international guidelines and exceed 2,3,7,8-TCDD's lowest adverse effect levels. The Bien Hoa fishponds are a completed human pathway for TCDD exposure.
GARNATJE, TERESA; GARCIA, SÒNIA; VILATERSANA, ROSER; VALLÈS, JOAN
2006-01-01
• Background and Aims Plant genome size is an important biological characteristic, with relationships to systematics, ecology and distribution. Currently, there is no information regarding nuclear DNA content for any Carthamus species. In addition to improving the knowledge base, this research focuses on interspecific variation and its implications for the infrageneric classification of this genus. Genome size variation in the process of allopolyploid formation is also addressed. • Methods Nuclear DNA samples from 34 populations of 16 species of the genus Carthamus were assessed by flow cytometry using propidium iodide. • Key Results The 2C values ranged from 2·26 pg for C. leucocaulos to 7·46 pg for C. turkestanicus, and monoploid genome size (1Cx-value) ranged from 1·13 pg in C. leucocaulos to 1·53 pg in C. alexandrinus. Mean genome sizes differed significantly, based on sectional classification. Both allopolyploid species (C. creticus and C. turkestanicus) exhibited nuclear DNA contents in accordance with the sum of the putative parental C-values (in one case with a slight reduction, frequent in polyploids), supporting their hybrid origin. • Conclusions Genome size represents a useful tool in elucidating systematic relationships between closely related species. A considerable reduction in monoploid genome size, possibly due to the hybrid formation, is also reported within these taxa. PMID:16390843
Sugimoto, M; Kojima, T; Asami, M; Iizuka, Y; Matsuda, K
1991-11-27
The effect of loxoprofen-Na, a novel non-steroidal anti-inflammatory drug with a prodrug property, on prostaglandin (PG) levels in the inflammatory tissue was investigated with a carrageenin-induced pleurisy model in rats. The intrapleural injection of carrageenin caused a marked increase in the levels of PGE2 and 6-keto-PGF1 alpha in the pleural exudate up to 3 hr after the injection. When [14C]PGE2 was injected into the cavity 2 hr after the carrageenin injection, the PG rapidly disappeared from the cavity (T 1/2 = 5 min). Thus, the PG level determined in the inflammatory exudate represents PG produced in the inflammatory tissue. Loxoprofen-Na, administered orally 2 hr after the carrageenin injection, dose-dependently inhibited the increase in the levels of PGs in the exudate 1 hr after administration (ID50 = 0.07 mg/kg for PGE2 and 0.10 mg/kg for 6-keto-PGF1 alpha). Indomethacin also inhibited PG production, but was less effective (ID50 = 0.24 mg/kg for PGE2 and 0.47 mg/kg for 6-keto-PGF1 alpha). Similar results were obtained 3 hr after the administration of these drugs (ID50 of PGE2 production = 0.14 mg/kg for loxoprofen-Na and 0.28 mg/kg for indomethacin). The time-course analysis of the effect of loxoprofen-Na showed that this drug had more immediate and stronger inhibitory activity than indomethacin. The relative potencies of suppression of protein leakage and leukocyte infiltration correlated well with the inhibition of PG production, but higher doses were needed for an obvious anti-inflammatory effect. The active metabolite (SRS trans-OH) of loxoprofen-Na determined in the inflammatory exudate 1 hr after oral administration of 0.2 and 2 mg/kg of loxoprofen-Na was 0.05 and 0.25 micrograms/mL, respectively. The concentration was sufficient to suppress PG production in the exudate, because the IC50 of the SRS trans-OH for PG production in vitro with leukocytes was 0.02 microgram/mL (0.01 microM). The potency of the SRS trans-OH metabolite to inhibit PGE2 production in leukocytes was about 20 times stronger than that of the parent compound and 3 times stronger than that of indomethacin.
Kinzinger, Gero S M; Fritz, Ulrike B; Sander, Franz-Günter; Diedrich, Peter R
2004-01-01
A modified pendulum appliance, including a distal screw and special preactivated pendulum springs (built-in straightening activation and toe-in bending), was used for bilateral maxillary molar distalization in 36 adolescent patients in various stages of the molar dentition. The patients were divided into 3 groups (PG 1-3) according to the stage of eruption of their second and third molars. In PG 1 (18 patients), eruption of the second molars had either not yet taken place or was not complete. In PG 2 (15 patients), the second molars had already developed as far as the occlusal plane, with the third molars at the budding stage. In PG 3 (3 patients), germectomy of the wisdom teeth had been carried out, and the first and second molars on both sides had completely erupted. Analysis of cephalograms to identify any changes in the sagittal plane showed that, in the direction of distalization, a tooth bud acts on the mesial neighboring tooth like a fulcrum, and that tipping of the first molars in patients in whom the second molar was still at the budding stage was thus greater. In patients whose second molars had erupted completely, the degree of tipping was greater again when a third molar bud was located in the direction of movement. After previously completed germectomy of the wisdom teeth, almost exclusively bodily distalization of both molars is possible, even without bands being applied to the second molars. However, if the first and second molars are distalized simultaneously with a pendulum appliance, the duration of therapy will be longer, greater forces will have to be applied, and more anchorage will be lost. Statistical analysis of the results of dental-angular measurements showed significant differences in the degree of molar tipping and reciprocal incisor protrusion. The degree of distal tipping of first molars was less in patients with erupted second molars (PG 2 and PG 3) than in those whose second molars were not yet erupted (PG 1). For instance, the measured angles were 0.9 degrees +/- 3.43 degrees (to the palatal plane) and 0.8 degrees +/- 3.4 degrees (to the anterior cranium floor) in PG 2, and -0.33 degrees +/- 0.58 degrees and 0.67 degrees +/- 2.08 degrees, respectively, in PG 3, contrasting with respective values of 5.89 degrees +/- 3.74 degrees and 5.36 degrees +/- 3.49 degrees in PG 1. Tipping of erupted second molars was much more marked in PG 2 (7.92 degrees +/- 5.83 degrees to the palatal plane and 7.55 degrees +/- 5.28 degrees to the anterior cranium floor), but much less pronounced in PG 3 (2 degrees +/- 1.73 degrees to the palatal plane and 2 degrees +/- 2 degrees to the anterior cranium floor) than the corresponding movement of the second budding-stage molars in PG 1 (4.06 degrees +/- 2.15 degrees and 3.97 degrees +/- 2.27 degrees, respectively). The degree of incisor protrusion occurring reciprocally with molar distalization was much less in these patients (measured angles of 3.28 degrees +/- 1.97 degrees and 2.89 degrees +/- 2.17 degrees to the palatal plane and anterior cranium floor, respectively) than in the patients presenting different stages of the dentition (angles of 5.5 degrees +/- 3.33 degrees and 6.03 degrees +/- 4.29 degrees, respectively, in PG 2, and angles of 5.5 degrees +/- 3.28 degrees and 6.67 degrees +/- 3.09 degrees, respectively, in PG 3). Moreover, measurement of dental casts in the horizontal plane showed not only the targeted mesiobuccal rotation of both maxillary molars, but also a vestibular drift of the unbanded second molars.
Spratt, Daniel E; Zumsteg, Zach; Ghadjar, Pirus; Pangasa, Misha; Pei, Xin; Fine, Samson W; Yamada, Yoshiya; Kollmeier, Marisa; Zelefsky, Michael J
2013-04-01
To analyze the effect of primary Gleason (pG) grade among a large cohort of Gleason 7 prostate cancer patients treated with external beam radiation therapy (EBRT). From May 1989 to January 2011, 1190 Gleason 7 patients with localized prostate cancer were treated with EBRT at a single institution. Of these patients, 613 had a Gleason 7 with a minimum of a sextant biopsy with nonfragmented cores and full biopsy core details available, including number of cores of cancer involved, percentage individual core involvement, location of disease, bilaterality, and presence of perineural invasion. Median follow-up was 6 years (range, 1-16 years). The prognostic implication for the following outcomes was analyzed: biochemical recurrence-free survival (bRFS), distant metastasis-free survival (DMFS), and prostate cancer-specific mortality (PCSM). The 8-year bRFS rate for pG3 versus pG4 was 77.6% versus 61.3% (P<.0001), DMFS was 96.8% versus 84.3% (P<.0001), and PCSM was 3.7% versus 8.1% (P=.002). On multivariate analysis, pG4 predicted for significantly worse outcome in all parameters. Location of disease (apex, base, mid-gland), perineural involvement, maximum individual core involvement, and the number of Gleason 3+3, 3+4, or 4+3 cores did not predict for distant metastases. Primary Gleason grade 4 independently predicts for worse bRFS, DMFS, and PCSM among Gleason 7 patients. Using complete core information can allow clinicians to utilize pG grade as a prognostic factor, despite not having the full pathologic details from a prostatectomy specimen. Future staging and risk grouping should investigate the incorporation of primary Gleason grade when complete biopsy core information is used. Copyright © 2013 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spratt, Daniel E.; Zumsteg, Zach; Ghadjar, Pirus
2013-04-01
Purpose: To analyze the effect of primary Gleason (pG) grade among a large cohort of Gleason 7 prostate cancer patients treated with external beam radiation therapy (EBRT). Methods and Materials: From May 1989 to January 2011, 1190 Gleason 7 patients with localized prostate cancer were treated with EBRT at a single institution. Of these patients, 613 had a Gleason 7 with a minimum of a sextant biopsy with nonfragmented cores and full biopsy core details available, including number of cores of cancer involved, percentage individual core involvement, location of disease, bilaterality, and presence of perineural invasion. Median follow-up was 6more » years (range, 1-16 years). The prognostic implication for the following outcomes was analyzed: biochemical recurrence-free survival (bRFS), distant metastasis-free survival (DMFS), and prostate cancer-specific mortality (PCSM). Results: The 8-year bRFS rate for pG3 versus pG4 was 77.6% versus 61.3% (P<.0001), DMFS was 96.8% versus 84.3% (P<.0001), and PCSM was 3.7% versus 8.1% (P=.002). On multivariate analysis, pG4 predicted for significantly worse outcome in all parameters. Location of disease (apex, base, mid-gland), perineural involvement, maximum individual core involvement, and the number of Gleason 3+3, 3+4, or 4+3 cores did not predict for distant metastases. Conclusions: Primary Gleason grade 4 independently predicts for worse bRFS, DMFS, and PCSM among Gleason 7 patients. Using complete core information can allow clinicians to utilize pG grade as a prognostic factor, despite not having the full pathologic details from a prostatectomy specimen. Future staging and risk grouping should investigate the incorporation of primary Gleason grade when complete biopsy core information is used.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
van Baren, Marijke J.; Bachy, Charles; Reistetter, Emily Nahas
Prasinophytes are widespread marine green algae that are related to plants. Abundance of the genus Micromonas has reportedly increased in the Arctic due to climate-induced changes. Thus, studies of these organisms are important for marine ecology and understanding Virdiplantae evolution and diversification. We generated evidence-based Micromonas gene models using proteomics and RNA-Seq to improve prasinophyte genomic resources. First, sequences of four chromosomes in the 22 Mb Micromonas pusilla (CCMP1545) genome were finished. Comparison with the finished 21 Mb Micromonas commoda (RCC299) shows they share ≤ 8,142 of ~10,000 protein-encoding genes, depending on the analysis method. Unlike RCC299 and other sequencedmore » eukaryotes, CCMP1545 has two abundant repetitive intron types and a high percent (26%) GC splice donors. Micromonas has more genus-specific protein families (19%) than other genome sequenced prasinophytes (11%). Comparative analyses using predicted proteomes from other prasinophytes reveal proteins likely related to scale formation and ancestral photosynthesis. Our studies also indicate that peptidoglycan (PG) biosynthesis enzymes have been lost in multiple independent events in select prasinophytes and most plants. However, CCMP1545, polar Micromonas CCMP2099 and prasinophytes from other claasses retain the entire PG pathway, like moss and glaucophyte algae. Multiple vascular plants that share a unique bi-domain protein also have the pathway, except the Penicillin-Binding-Protein. Alongside Micromonas experiments using antibiotics that halt bacterial PG biosynthesis, the findings highlight unrecognized phylogenetic complexity in the PG-pathway retention and implicate a role in chloroplast structure of division in several extant Vridiplantae lineages. Extensive differences in gene loss and architecture between related prasinophytes underscore their extensive divergence. PG biosynthesis genes from the cyanobacterial endosymbiont that became the plastid, have been selectively retained in some plants and algae, implying a biological function. As a result, our studies provide robust genomic resources for emerging model algae, advancing knowledge of marine phytoplankton and plant evolution.« less
van Baren, Marijke J.; Bachy, Charles; Reistetter, Emily Nahas; ...
2016-03-31
Prasinophytes are widespread marine green algae that are related to plants. Abundance of the genus Micromonas has reportedly increased in the Arctic due to climate-induced changes. Thus, studies of these organisms are important for marine ecology and understanding Virdiplantae evolution and diversification. We generated evidence-based Micromonas gene models using proteomics and RNA-Seq to improve prasinophyte genomic resources. First, sequences of four chromosomes in the 22 Mb Micromonas pusilla (CCMP1545) genome were finished. Comparison with the finished 21 Mb Micromonas commoda (RCC299) shows they share ≤ 8,142 of ~10,000 protein-encoding genes, depending on the analysis method. Unlike RCC299 and other sequencedmore » eukaryotes, CCMP1545 has two abundant repetitive intron types and a high percent (26%) GC splice donors. Micromonas has more genus-specific protein families (19%) than other genome sequenced prasinophytes (11%). Comparative analyses using predicted proteomes from other prasinophytes reveal proteins likely related to scale formation and ancestral photosynthesis. Our studies also indicate that peptidoglycan (PG) biosynthesis enzymes have been lost in multiple independent events in select prasinophytes and most plants. However, CCMP1545, polar Micromonas CCMP2099 and prasinophytes from other claasses retain the entire PG pathway, like moss and glaucophyte algae. Multiple vascular plants that share a unique bi-domain protein also have the pathway, except the Penicillin-Binding-Protein. Alongside Micromonas experiments using antibiotics that halt bacterial PG biosynthesis, the findings highlight unrecognized phylogenetic complexity in the PG-pathway retention and implicate a role in chloroplast structure of division in several extant Vridiplantae lineages. Extensive differences in gene loss and architecture between related prasinophytes underscore their extensive divergence. PG biosynthesis genes from the cyanobacterial endosymbiont that became the plastid, have been selectively retained in some plants and algae, implying a biological function. As a result, our studies provide robust genomic resources for emerging model algae, advancing knowledge of marine phytoplankton and plant evolution.« less
Hoffenberg, Simon; Powell, Rebecca; Carpov, Alexei; Wagner, Denise; Wilson, Aaron; Kosakovsky Pond, Sergei; Lindsay, Ross; Arendt, Heather; DeStefano, Joanne; Phogat, Sanjay; Poignard, Pascal; Fling, Steven P.; Simek, Melissa; LaBranche, Celia; Montefiori, David; Wrin, Terri; Phung, Pham; Burton, Dennis; Koff, Wayne; King, C. Richter; Parks, Christopher L.
2013-01-01
Broadly neutralizing antibodies (bNAbs) PG9 and PG16 were isolated from an International AIDS Vaccine Initiative (IAVI) Protocol G subject infected with human immunodeficiency virus type 1 (HIV-1) clade A. Both antibodies are highly potent and neutralize greater than 70% of viruses tested. We sought to begin immunogen design based on viral sequences from this patient; however, pseudoviruses prepared with 19 envelope sequences from this subject were resistant to neutralization by PG9 and PG16. Therefore, we used a bioinformatics approach to identify closely related viruses that were potentially sensitive to PG9 and PG16. A most-recent common ancestor (MRCA) sequence for the viral envelope (Env) was determined and aligned with 99 subtype A gp160 sequences from the Los Alamos HIV database. Virus BG505.W6M.ENV.C2 (BG505) was found to have the highest degree of homology (73%) to the MRCA sequence. Pseudoviruses prepared with this Env were sensitive to neutralization with a broad panel of bNAbs, including PG9 and PG16. When expressed by 293T cells as soluble gp120, the BG505 monomer bound well to both PG9 and PG16. We further showed that a point mutation (L111A) enabled more efficient production of a stable gp120 monomer that preserves the major neutralization epitopes. Finally, we showed that an adjuvanted formulation of this gp120 protein elicited neutralizing antibodies in rabbits (following a gp120 DNA vaccine prime) and that the antisera competed with bNAbs from 3 classes of nonoverlapping epitopes. Thus, the BG505 Env protein warrants further investigation as an HIV vaccine candidate, as a stand-alone protein, or as a component of a vaccine vector. PMID:23468492
Zhao, Y; Czilwik, G; Klein, V; Mitsakakis, K; Zengerle, R; Paust, N
2017-05-02
We present a fully automated centrifugal microfluidic method for particle based protein immunoassays. Stick-pack technology is employed for pre-storage and release of liquid reagents. Quantitative layout of centrifugo-pneumatic particle handling, including timed valving, switching and pumping is assisted by network simulations. The automation is exclusively controlled by the spinning frequency and does not require any additional means. New centrifugal microfluidic process chains are developed in order to sequentially supply wash buffer based on frequency dependent stick-pack opening and pneumatic pumping to perform two washing steps from one stored wash buffer; pre-store and re-suspend functionalized microparticles on a disk; and switch between the path of the waste fluid and the path of the substrate reaction product with 100% efficiency. The automated immunoassay concept is composed of on demand ligand binding, two washing steps, the substrate reaction, timed separation of the reaction products, and termination of the substrate reaction. We demonstrated separation of particles from three different liquids with particle loss below 4% and residual liquid remaining within particles below 3%. The automated immunoassay concept was demonstrated by means of detecting C-reactive protein (CRP) in the range of 1-81 ng ml -1 and interleukin 6 (IL-6) in the range of 64-13 500 pg ml -1 . The limit of detection and quantification were 1.0 ng ml -1 and 2.1 ng ml -1 for CRP and 64 pg ml -1 and 205 pg ml -1 for IL-6, respectively.
A new polymorphic pepsinogen locus (Pg-2) in the rat (Rattus norvegicus).
Hamada, S; Yamada, J; Bender, K; Adams, M
1987-07-01
Only two types of pepsinogens, which are products of the Pg-1 locus, are present in rat urine. In gastric mucosa, however, additional pepsinogen isozymes are expressed. We have found a polymorphism for rat gastric mucosa pepsinogen using agarose gel electrophoresis. Some inbred rat strains expressed a pepsinogen band, while others did not. The trait was found to be controlled by a single autosomal locus. We tentatively designated the locus as Pg-2 with two alleles, Pg-2a for the one controlling presence of the band and Pg-2o for the one controlling absence. Linkage analysis using BN and TM strains revealed that Pg-2 was closely linked to Pg-1 (3.7 +/- 1.8 cM), and that it did not belong to LG I (Hbb and p), LG II (Acon-1 and Mup-1), LG IV (Hao-1 and Svp-1), LG V (Es-1 and Es-3), LG VI (Gc and h), LG IX (RT1), LG X (Fh and Pep-3), nor a LG containing Ahd-2 (as yet undetermined).
Two-Step Approach for the Prediction of Future Type 2 Diabetes Risk
Abdul-Ghani, Muhammad A.; Abdul-Ghani, Tamam; Stern, Michael P.; Karavic, Jasmina; Tuomi, Tiinamaija; Bo, Insoma; DeFronzo, Ralph A.; Groop, Leif
2011-01-01
OBJECTIVE To develop a model for the prediction of type 2 diabetes mellitus (T2DM) risk on the basis of a multivariate logistic model and 1-h plasma glucose concentration (1-h PG). RESEARCH DESIGN AND METHODS The model was developed in a cohort of 1,562 nondiabetic subjects from the San Antonio Heart Study (SAHS) and validated in 2,395 nondiabetic subjects in the Botnia Study. A risk score on the basis of anthropometric parameters, plasma glucose and lipid profile, and blood pressure was computed for each subject. Subjects with a risk score above a certain cut point were considered to represent high-risk individuals, and their 1-h PG concentration during the oral glucose tolerance test was used to further refine their future T2DM risk. RESULTS We used the San Antonio Diabetes Prediction Model (SADPM) to generate the initial risk score. A risk-score value of 0.065 was found to be an optimal cut point for initial screening and selection of high-risk individuals. A 1-h PG concentration >140 mg/dL in high-risk individuals (whose risk score was >0.065) was the optimal cut point for identification of subjects at increased risk. The two cut points had 77.8, 77.4, and 44.8% (for the SAHS) and 75.8, 71.6, and 11.9% (for the Botnia Study) sensitivity, specificity, and positive predictive value, respectively, in the SAHS and Botnia Study. CONCLUSIONS A two-step model, based on the combination of the SADPM and 1-h PG, is a useful tool for the identification of high-risk Mexican-American and Caucasian individuals. PMID:21788628
Rashidi Nodeh, Hamid; Wan Ibrahim, Wan Aini; Kamboh, Muhammad Afzal; Sanagi, Mohd Marsin
2017-01-01
A new graphene-based tetraethoxysilane-methyltrimethoxysilane sol-gel hybrid magnetic nanocomposite (Fe 3 O 4 @G-TEOS-MTMOS) was synthesised, characterized and successfully applied in magnetic solid-phase extraction (MSPE) for simultaneous analysis of polar and non-polar organophosphorus pesticides from several water samples. The Fe 3 O 4 @G-TEOS-MTMOS nanocomposite was characterized using Fourier transform-infrared spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy and X-ray diffraction. Separation, determination and quantification were achieved using gas chromatography coupled with micro electron capture detector. Adsorption capacity of the sorbent was calculated using Langmuir equation. MSPE was linear in the range 100-1000 pg mL -1 for phosphamidon and dimethoate, and 10-100 pg mL -1 for chlorpyrifos and diazinon, with limit of detection (S/N = 3) of 19.8, 23.7, 1.4 and 2.9 pg mL -1 for phosphamidon, dimethoate, diazinon and chlorpyrifos, respectively. The LODs obtained is well below the maximum residual level (100 pg mL -1 ) as set by European Union for pesticides in drinking water. Acceptable precision (%RSD) was achieved for intra-day (1.3-8.7%, n = 3) and inter-day (7.6-17.8%, n = 15) analyses. Fe 3 O 4 @G-TEOS-MTMOS showed high adsorption capacity (54.4-76.3 mg g -1 ) for the selected OPPs. No pesticide residues were detected in the water samples analysed. Excellent extraction recoveries (83-105%) were obtained for the spiked OPPs from tap, river, lake and sea water samples. The newly synthesised Fe 3 O 4 @G-TEOS-MTMOS showed high potential as adsorbent for OPPs analysis. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lipskind, Shane; Lindsey, Jennifer S; Gerami-Naini, Behzad; Eaton, Jennifer L; O'Connell, Daniel; Kiezun, Adam; Ho, Joshua W K; Ng, Nicholas; Parasar, Parveen; Ng, Michelle; Nickerson, Michael; Demirci, Utkan; Maas, Richard; Anchan, Raymond M
2018-05-01
Embryoid bodies (EBs) can serve as a system for evaluating pluripotency, cellular differentiation, and tissue morphogenesis. In this study, we use EBs derived from mouse embryonic stem cells (mESCs) and human amniocyte-derived induced pluripotent stem cells (hAdiPSCs) as a model for ovarian granulosa cell (GC) development and steroidogenic cell commitment. We demonstrated that spontaneously differentiated murine EBs (mEBs) and human EBs (hEBs) displayed ovarian GC markers, such as aromatase (CYP19A1), FOXL2, AMHR2, FSHR, and GJA1. Comparative microarray analysis identified both shared and unique gene expression between mEBs and the maturing mouse ovary. Gene sets related to gonadogenesis, lipid metabolism, and ovarian development were significantly overrepresented in EBs. Of the 29 genes, 15 that were differentially regulated in steroidogenic mEBs displayed temporal expression changes between embryonic, postnatal, and mature ovarian tissues by polymerase chain reaction. Importantly, both mEBs and hEBs were capable of gonadotropin-responsive estradiol (E2) synthesis in vitro (217-759 pg/mL). Live fluorescence-activated cell sorting-sorted AMHR2 + granulosa-like cells from mEBs continued to produce E2 after purification (15.3 pg/mL) and secreted significantly more E2 than AMHR2 - cells (8.6 pg/mL, P < .05). We conclude that spontaneously differentiated EBs of both mESC and hAdiPSC origin can serve as a biologically relevant model for ovarian GC differentiation and steroidogenic cell commitment. These cells should be further investigated for therapeutic uses, such as stem cell-based hormone replacement therapy and in vitro maturation of oocytes.
Nuruzzaman, Mohammed; Cao, Hongzhe; Xiu, Hao; Luo, Tiao; Li, Jijia; Chen, Xianghui; Luo, Junli; Luo, Zhiyong
2016-02-01
WRKY proteins belong to a transcription factor (TF) family and play dynamic roles in many plant processes, including plant responses to abiotic and biotic stresses, as well as secondary metabolism. However, no WRKY gene in Panax ginseng C.A. Meyer has been reported to date. In this study, a number of WRKY unigenes from methyl jasmonate (MeJA)-treated adventitious root transcriptome of this species were identified using next-generation sequencing technology. A total of 48 promising WRKY unigenes encoding WRKY proteins were obtained by eliminating wrong and incomplete open reading frame (ORF). Phylogenetic analysis reveals 48 WRKY TFs, including 11 Group I, 36 Group II, and 1 Group III. Moreover, one MeJA-responsive unigene designated as PgWRKY1 was cloned and characterized. It contains an entire ORF of 1077 bp and encodes a polypeptide of 358 amino acid residues. The PgWRKY1 protein contains a single WRKY domain consisting of a conserved amino acid sequence motif WRKYGQK and a C2H2-type zinc-finger motif belonging to WRKY subgroup II-d. Subcellular localization of PgWRKY1-GFP fusion protein in onion and tobacco epidermis cells revealed that PgWRKY1 was exclusively present in the nucleus. Quantitative real-time polymerase chain reaction analysis demonstrated that the expression of PgWRKY1 was relatively higher in roots and lateral roots compared with leaves, stems, and seeds. Importantly, PgWRKY1 expression was significantly induced by salicylic acid, abscisic acid, and NaCl, but downregulated by MeJA treatment. These results suggested that PgWRKY1 might be a multiple stress-inducible gene responding to hormones and salt stresses. © The Author 2015. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.
Global Soil Respiration: Interaction with Environmental Variables and Response to Climate Change
NASA Astrophysics Data System (ADS)
Jian, J.; Steele, M.
2016-12-01
Background, methods, objectivesTerrestrial ecosystems take up around 1.7 Pg C per year; however, the role of terrestrial ecosystems as a carbon sink may change to carbon source by 2050, as a result of positive feedback of soil respiration response to global warming. Nevertheless, limited evidence shows that soil carbon is decreasing and the role of terrestrial ecosystems is changing under warming. One possibility is the positive feedback may slow due to the acclimation of soil respiration as a result of decreasing temperature sensitivity (Q10) with warming. To verify and quantify the uncertainty in soil carbon cycling and feedbacks to climate change, we assembled soil respiration observations from 1961 to 2014 from 724 publications into a monthly global soil respiration database (MSRDB), which included 13482 soil respiration measurements together with 38 other ancillary measurements from 538 sites. Using this database we examined macroscale variation in the relationship between soil respiration and air temperature, precipitation, leaf area index and soil properties. We also quantified global soil respiration, the sources of uncertainty, and its feedback to warming based on climate region-oriented models with variant Q10function. Results and ConclusionsOur results showed substantial heterogeneity in the relationship between soil respiration and environmental factors across different climate regions. For example, soil respiration was strongly related to vegetation (via leaf area index) in colder regions, but not in tropical region. Only in tropical and arid regions did soil properties explain any variation in soil respiration. Global annual mean soil respiration from 1961 to 2014 was estimated to be 72.41 Pg C yr-1 based on monthly global soil respiration database, 25 Pg lower than estimated based on yearly soil respiration database. By using the variable Q10 models, we estimated that global soil respiration increased at a rate of 0.03 Pg C yr-1 from 1961 to 2014, smaller than previous studies ( 0.1 Pg C yr-1). The substantial variations in these relationships suggest that regional scales is important for understanding and prediction of global carbon cycling and how it response to climate change.
Effect of simulated acid rain on fluorine mobility and the bacterial community of phosphogypsum.
Wang, Mei; Tang, Ya; Anderson, Christopher W N; Jeyakumar, Paramsothy; Yang, Jinyan
2018-06-01
Contamination of soil and water with fluorine (F) leached from phosphogypsum (PG) stacks is a global environmental issue. Millions of tons of PG is produced each year as a by-product of fertilizer manufacture, and in China, weathering is exacerbated by acid rain. In this work, column leaching experiments using simulated acid rain were run to evaluate the mobility of F and the impact of weathering on native bacterial community composition in PG. After a simulated summer rainfall, 2.42-3.05 wt% of the total F content of PG was leached and the F concentration in leachate was above the quality standard for surface water and groundwater in China. Acid rain had no significant effect on the movement of F in PG. A higher concentration of F was observed at the bottom than the top section of PG columns suggesting mobility and reprecipitation of F. Throughout the simulation, the PG was environmentally safe according the TCLP testing. The dominant bacteria in PG were from the Enterococcus and Bacillus genus. Bacterial community composition in PG leached by simulated acid rain (pH 3.03) was more abundant than at pH 6.88. Information on F mobility and bacterial community in PG under conditions of simulated rain is relevant to management of environmental risk in stockpiled PG waste.
Liu, Yu; Wang, Can; Chen, Minpeng
2017-05-01
Research on carbon cycling has attracted attention from both scientists and policy-makers. Based on material flow analysis, this study systematically budgets the carbon inputs, outputs and balance from 1980 to 2013 for China's agro-ecosystem and its sub-systems, including agricultural land use, livestock breeding and rural life. The results show that from 1980 to 2013, both the carbon input and output were growing gradually, with the carbon input doubling from 1.6PgC/year in 1980 to 3.4PgC/year in 2013, while carbon output grew from 2.2PgC/year in 1980 to 3.8PgC/year in 2013. From 1980 to 2013, the crop production system in China has remained a carbon source, and the agricultural land uses were also almost all carbon sources instead of carbon sinks. As soil carbon stock plays a very important role in deciding the function of China's agro-ecosystem as a carbon sink or source, practices that can promote carbon storage and sequestration will be an essential component of low carbon agriculture development in China. Copyright © 2016. Published by Elsevier B.V.
Alecu, M; Geleriu, L; Coman, G; Gălăţescu, L
1998-01-01
Serological level of interleukin-1 (IL-1), Interleukin-2 (IL-2), Interleukin-6 (IL-6) and tumour necrosis factor (TNF) alpha was investigated in 26 patients with scleroderma, divided into three lots, by the extension and the progress of the disease. Determinations were performed by ELISA in attack and in remission (after treatment with prednison). Normal values: IL-1 (0-5 pg/ml), IL-2 (0-5 pg/ml), IL-6 (5-15 pg/ml), TNF (0-16 pg/ml). Lot A. Results obtained at the first determination showed that IL-1 is elevated in 4 cases (10-15 pg/ml), IL-2 in 5 cases (10-32 pg/ml), IL-6 in 5 cases (15-42 pg/ml) and TNF in 4 cases (18-34 pg/ml). In the second determination IL-1 was increased in 1 case (8 pg/ml), IL-2 in 1 case (9 pg/ml), IL-6 in 2 cases (12 pg/ml) and TNF was normal. Lot B. In the first determination IL-1 was elevated in 5 cases (8-12 pg/ml), IL-2 in 5 cases (10-15 pg/ml), IL-6 in 7 cases (16-20 pg/ml) and TNF was raised in 3 cases (18-25 pg/ml). At the second determination IL-1 showed normal values in all the cases, IL-2 was raised in 2 cases (10 pg/ml), IL-6 in 2 cases (12.15 pg/ml), TNF in 1 case (20 pg/ml). Lot C. In the first determination there were raised values in 4 cases for IL-1 (6-8 pg/ml), 3 cases for IL-2 (10-18 pg/ml), 5 cases for IL-6 (18-20 pg/ml), 2 cases for TNF (20 pg/ml). At the second determination IL-2 was elevated in 1 case (10 pg/ml), IL-6 in 1 case (15 pg/ml). We consider that in scleroderma there is a disturbance of the investigated cytokines due to the activation and involvement of the secretory cells into the pathogenesis of the disease. The increase of the serological levels of IL-1, IL-2, IL-6 and TNF depends on the extension of the lesions and the clinical and biological activity periods of the disease. The absence of the increase of the serological levels does not exclude their activity at the lesional site.
Chattopadhyay, Sudipta; George, Anish; John, Joseph; Sathyapalan, Thozhukat
2018-05-01
We evaluate prevalence of new abnormal glucose tolerance (AGT) in post-MI survivors without known diabetes (DM) if guidelines are followed and compare the ability of admission (APG), fasting (FPG) and 2-h post-load plasma glucose (2h-PG) to predict prognosis. A total of 674 patients were followed up for 4 years for incidence of major adverse cardiovascular events (MACE) of cardiovascular death, non-fatal re-infarction or non-haemorrhagic stroke. Ability of models including APG, FPG and 2h-PG to predict MACE was compared. Of the total, 93-96% of impaired glucose tolerance and 64-75% of DM would be missed with current guidelines. MACE was higher in the upper quartiles of 2h-PG. When 2h-PG and FPG were included simultaneously in models, only 2h-PG predicted MACE (HR 1.12, CI 1.04-1.20, p = 0.0012), all cause mortality (HR 1.17, CI 1.05-1.30, p = 0.0039), cardiovascular mortality (HR 1.17, CI 1.02-1.33, p = 0.0205) and non-fatal MI (HR 1.10, CI 1.01-1.20, p = 0.0291). Adding 2h-PG significantly improved ability of models including FPG (χ 2 = 16.01, df = 1, p = 0.0001) or FPG and APG (χ 2 = 17.36, df = 1, p = 0.000) to predict MACE. Model including 2h-PG only had the lowest Akaike's information criteria and highest Akaike weights suggesting that this was the best in predicting events. Adding 2h-PG to models including FPG or APG with other co-variates yielded continuous net reclassification improvement (NRI) of 0.22 (p = 0.026) and 0.27 (p = 0.005) and categorical NRI of 0.09 (p = 0.032) and 0.12 (p = 0.014), respectively. Adding 2 h-PG to models including only FPG, only APG and both yielded integrated discrimination improvement of 0.012 (p = 0.015), 0.022 (p = 0.001) and 0.013 (p = 0.014), respectively. AGT is under-diagnosed on current guidelines. 2h-PG is a better predictor of prognosis compared to APG and FPG.
Effect of subseabed salt domes on Tidal Residual currents in the Persian Gulf
NASA Astrophysics Data System (ADS)
Mashayekh Poul, Hossein; Backhaus, Jan; Dehghani, Ali; Huebner, Udo
2016-05-01
Geological studies in the Persian Gulf (PG) have revealed the existence of subseabed salt-domes. With suitable filtering of a high-resolution PG seabed topography, it is seen that the domes leave their signature in the seabed, i.e., numerous hills and valleys with amplitudes of several tens of meters and radii from a few up to tens of kilometers. It was suspected that the "shark skin" of the PG seabed may affect the tidal residual flow. The interaction of tidal dynamics and these obstacles was investigated in a nonlinear hydrodynamic numerical tidal model of the PG. The model was first used to characterize flow patterns of residual currents generated by a tidal wave passing over symmetric, elongated and tilted obstacles. Thereafter it was applied to the entire PG. The model was forced at its open boundary by the four dominant tidal constituents residing in the PG. Each tidal constituent was simulated separately. Results, i.e., tidal residual currents in the PG, as depicted by Lagrangian trajectories reveal a stationary flow that is very rich in eddies. Each eddy can be identified with a topographic obstacle. This confirms that the tidal residual flow field is strongly influenced by the nonlinear interaction of the tidal wave with the bottom relief which, in turn, is deformed by salt-domes beneath the seabed. Different areas of maximum residual current velocities are identified for major tidal constituents. The pattern of trajectories indicates the presence of two main cyclonic gyres and several adjacent gyres rotating in opposite directions and a strong coastal current in the northern PG.
Ouhara, K; Munenaga, S; Kajiya, M; Takeda, K; Matsuda, S; Sato, Y; Hamamoto, Y; Iwata, T; Yamasaki, S; Akutagawa, K; Mizuno, N; Fujita, T; Sugiyama, E; Kurihara, H
2018-06-01
RNA-binding proteins (RBPs) regulate mRNA stability by binding to the 3'-untranslated region (UTR) region of mRNA. Human antigen-R (HuR), one of the RBPs, is involved in the progression of diseases, such as rheumatoid arthritis, diabetes mellitus and some inflammatory diseases. Interleukin (IL)-6 is a major inflammatory cytokine regulated by HuR binding to mRNA. Periodontal disease (PD) is also an inflammatory disease caused by elevations in IL-6 following an infection by periodontopathogenic bacteria. The involvement of HuR in the progression of PD was assessed using in-vitro and in-vivo experiments. Immunohistochemistry of inflamed periodontal tissue showed strong staining of HuR in the epithelium and connective tissue. HuR mRNA and protein level was increased following stimulation with Porphyromonas gingivalis (Pg), one of the periodontopathogenic bacteria, lipopolysacchride (LPS)-derived from Pg (PgLPS) and tumour necrosis factor (TNF)-α in OBA-9, an immortalized human gingival epithelial cell. The luciferase activity of 3'-UTR of IL-6 mRNA was increased by TNF-α, Pg and PgLPS in OBA-9. Luciferase activity was also increased in HuR-over-expressing OBA-9 following a bacterial stimulation. Down-regulation of HuR by siRNA resulted in a decrease in mRNA expression and production of IL-6. In contrast, the over-expression of HuR increased IL-6 mRNA expression and production in OBA-9. The HuR inhibitor, quercetin, suppressed Pg-induced HuR mRNA expression and IL-6 production in OBA-9. An oral inoculation with quercetin also inhibited bone resorption in ligature-induced periodontitis model mice as a result of down-regulation of IL-6. These results show that HuR modulates inflammatory responses by regulating IL-6. © 2018 British Society for Immunology.
Alyass, Akram; Almgren, Peter; Akerlund, Mikael; Dushoff, Jonathan; Isomaa, Bo; Nilsson, Peter; Tuomi, Tiinamaija; Lyssenko, Valeriya; Groop, Leif; Meyre, David
2015-01-01
The relevance of the OGTT in predicting type 2 diabetes is unclear. We assessed the performance of 14 OGTT glucose traits in type 2 diabetes prediction. We studied 2,603 and 2,386 Europeans from the Botnia study and Malmö Prevention Project (MPP) cohorts with baseline OGTT data. Over a follow-up period of 4.94 years and 23.5 years, 155 (5.95%) and 467 (19.57%) participants, respectively, developed type 2 diabetes. The main outcome was incident type 2 diabetes. One-hour plasma glucose (1h-PG) was a fair/good predictor of incident type 2 diabetes in the Botnia study and MPP (AUC for receiver operating characteristic [AUCROC] 0.80 [0.77, 0.84] and 0.70 [0.68, 0.73]). 1h-PG alone outperformed the prediction model of multiple clinical risk factors (age, sex, BMI, family history of type 2 diabetes) in the Botnia study and MPP (AUCROC 0.75 [0.72, 0.79] and 0.67 [0.64, 0.70]). The same clinical risk factors added to 1h-PG modestly increased prediction for incident type 2 diabetes (Botnia, AUCROC 0.83 [0.80, 0.86]; MPP, AUCROC 0.74 [0.72, 0.77]). 1h-PG also outperformed HbA1c in predicting type 2 diabetes in the Botnia cohort. A 1h-PG value of 8.9 mmol/l and 8.4 mmol/l was the optimal cut-point for initial screening and selection of high-risk individuals in the Botnia study and MPP, respectively, and represented 30% and 37% of all participants in these cohorts. High-risk individuals had a substantially increased risk of incident type 2 diabetes (OR 8.0 [5.5, 11.6] and 3.8 [3.1, 4.7]) and captured 75% and 62% of all incident type 2 diabetes in the Botnia study and MPP. 1h-PG is a valuable prediction tool for identifying adults at risk for future type 2 diabetes.
2018-01-01
We explore the ideas and advances surrounding the genetic basis of pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG). As PG is the leading cause of nontraumatic blindness in young adults and current tailored interventions have proven ineffective, a better understanding of the underlying causes of PDS, PG, and their relationship is essential. Despite PDS being a subclinical disease, a large proportion of patients progress to PG with associated vision loss. Decades of research have supported a genetic component both for PDS and conversion to PG. We review the body of evidence supporting a genetic basis in humans and animal models and reevaluate classical mechanisms of PDS/PG considering this new evidence. PMID:29780638
Lahola-Chomiak, Adrian A; Walter, Michael A
2018-01-01
We explore the ideas and advances surrounding the genetic basis of pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG). As PG is the leading cause of nontraumatic blindness in young adults and current tailored interventions have proven ineffective, a better understanding of the underlying causes of PDS, PG, and their relationship is essential. Despite PDS being a subclinical disease, a large proportion of patients progress to PG with associated vision loss. Decades of research have supported a genetic component both for PDS and conversion to PG. We review the body of evidence supporting a genetic basis in humans and animal models and reevaluate classical mechanisms of PDS/PG considering this new evidence.
Change of Peripheral Blood Treg/Thl7 in Cognitive Impairment with Chronic Renal Failure Patients.
Wang, Jie; Li, Xue-Bin; Huang, Peng; Huang, Mei-Ying; Gu, Xian-Jun
2018-01-01
To investigate the changes in peripheral blood Treg/Th17 cell balance and its significance in patients with chronic renal failure (CRF) and cognitive impairment. A total of 71 patients with CRF were enrolled as a study group. The patients were divided into a cognitive impairment group and a normal cognitive function group according to the Mini-Mental State Examination (MMSE). Peripheral blood Treg and Th17 cells were analyzed by flow cytometry and their relevant cytokines (IL-17, IL-10 and TGF-β) and other biochemical indicators, including C-reactive protein (CRP) and IL-6, were determined by ELISA. Thepatients with both CRF and cognitive impairment were older than the cognitive normal groups. Peripheral blood Treg cells by Flow cytometry (the CRF cognitive impairment group 5.57±1.3%, CRF group with normal cognitive function 7.5 ± 0.9% and normal control group 9.7 ± 1.7%,P<0.05) and its related cytokines (IL-10 and TGF-β) by ELISA detection were lower in the group with cognitive impairment than in the group without cognitive impairment ( IL-10, 7.4±4.2 pg/mL, 13.8±3.9 pg/mL, 18.3±3.2 pg/mL; TGF-β 335.6±175.3 pg/mL, 512.7 ± 114.6 pg/mL, 953.8±373.4 pg/mL P < 0.05, respectively).However, Th17 cell numbers (the CRF cognitive impairment group 3.3 ± 0.7%, CRF group with normal cognitive function2.2 ± 0.5% and normal control group 1.5 ± 0.3%),and cytokine levels (IL-17, IL-6 and CRP) were higher in the group with cognitive impairment IL-6 (21.3 ± 5.1 pg/mL), IL-17 (18.5 ± 4.2 pg/mL) and CRP (20.3 ± 5.9 mg/L) in the CRF group with cognitive impairment when compared with the CRF group and normal cognitive function (12.2 ± 4.5 pg/mL, 12.1 ± 3.7 pg/mL and 13.5 ± 4.6 mg/L, respectively) or the normal control group (9.2 ± 5.8 pg/mL, 7.4 ± 2.6 pg/mL and 3.2 ± 1.3 mg/L, respectively, P<0.05). The frequencies of Treg in patients with CRF were positively correlated with the MMSE scores ((r = 0.518, P < 0.05), but the Th17 numbers were negatively correlated (r = -0.435, P < 0.05). An imbalance of peripheral blood Treg/Th17 cells is associated with cognitive impairment in patients with CRF. © 2018 The Author(s). Published by S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Liu, Yibo; Ju, Weimin; He, Honglin; Wang, Shaoqiang; Sun, Rui; Zhang, Yuandong
2013-03-01
Net primary productivity (NPP) is an important component of the terrestrial carbon cycle. Accurately mapping the spatial-temporal variations of NPP in China is crucial for global carbon cycling study. In this study the process-based Boreal Ecosystem Productivity Simulator (BEPS) was employed to study the changes of NPP in China's ecosystems for the period from 2000 to 2010. The BEPS model was first validated using gross primary productivity (GPP) measured at typical flux sites and forest NPP measured at different regions. Then it was driven with leaf area index (LAI) inversed from the Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance and land cover products and meteorological data interpolated from observations at 753 national basic meteorological stations to simulate NPP at daily time steps and a spatial resolution of 500 m from January 1, 2000 to December 31, 2010. Validations show that BEPS is able to capture the seasonal variations of tower-based GPP and the spatial variability of forest NPP in different regions of China. Estimated national total of annual NPP varied from 2.63 to 2.84Pg C·yr-1, averaging 2.74 Pg C·yr-1 during the study period. Simulated terrestrial NPP shows spatial patterns decreasing from the east to the west and from the south to the north, in association with land cover types and climate. South-west China makes the largest contribution to the national total of NPP while NPP in the North-west account for only 3.97% of the national total. During the recent 11 years, the temporal changes of NPP were heterogamous. NPP increased in 63.8% of China's landmass, mainly in areas north of the Yangtze River and decreased in most areas of southern China, owing to the low temperature freezing in early 2008 and the severe drought in late 2009.
TESTING RELATIVISTIC REFLECTION AND RESOLVING OUTFLOWS IN PG 1211+143 WITH XMM-NEWTON AND NuSTAR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lobban, A. P.; Pounds, K.; Vaughan, S.
We analyze the broad-band X-ray spectrum (0.3–50 keV) of the luminous Seyfert 1/quasar PG 1211+143—the archetypal source for high-velocity X-ray outflows—using near-simultaneous XMM-Newton and NuSTAR observations. We compare pure relativistic reflection models with a model including the strong imprint of photoionized emission and absorption from a high-velocity wind, finding a spectral fit that extrapolates well over the higher photon energies covered by NuSTAR . Inclusion of the high signal-to-noise ratio XMM-Newton spectrum provides much tighter constraints on the model parameters, with a much harder photon index/lower reflection fraction compared to that from the NuSTAR data alone. We show that puremore » relativistic reflection models are not able to account for the spectral complexity of PG 1211+143 and that wind absorption models are strongly required to match the data in both the soft X-ray and Fe K spectral regions. In confirming the significance of previously reported ionized absorption features, the new analysis provides a further demonstration of the power of combining the high throughput and resolution of long-look XMM-Newton observations with the unprecedented spectral coverage of NuSTAR .« less
Brambilla, Gianfranco; De Filippis, Stefania Paola; Iamiceli, Anna Laura; Iacovella, Nicola; Abate, Vittorio; Aronica, Vincenzo; Di Marco, Vincenzo; di Domenico, Alessandro
2011-02-01
An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems. Copyright ©, International Association for Food Protection
Green, Cheryl L; Nahhas, Ramzi W; Scoglio, Arielle A; Elman, Igor
2017-03-01
Background Excessive gambling is considered to be a part of the addiction spectrum. Stress-like emotional states are a key feature both of pathological gambling (PG) and of substance addiction. In substance addiction, stress symptomatology has been attributed in part to "anti-reward" allostatic neuroadaptations, while a potential involvement of anti-reward processes in the course of PG has not yet been investigated. Methods To that end, individuals with PG (n = 22) and mentally healthy subjects (n = 13) were assessed for trauma exposure and post-traumatic stress symptomatology (PTSS) using the Life Events Checklist and the Civilian Mississippi Scale, respectively. Results In comparison with healthy subjects, individuals with PG had significantly greater PTSS scores including greater physiological arousal sub-scores. The number of traumatic events and their recency were not significantly different between the groups. In the PG group, greater gambling severity was associated with more PTSS, but neither with traumatic events exposure nor with their recency. Conclusions Our data replicate prior reports on the role of traumatic stress in the course of PG and extend those findings by suggesting that the link may be derived from the anti-reward-type neuroadaptation rather than from the traumatic stress exposure per se.
Wu, Q; Baek, S-Y; Fang, M; Chang, Y-S
2010-06-01
Polybrominated diphenyl ethers (PBDEs) are considered harmful to human health because of their toxicities and persistence in environments. In the current study, the distribution and fate of PBDEs in classrooms and computer rooms in 17 elementary schools in South Korea have been described. Eight congeners (brominated diphenyl ether-28, -47, -99, -100, -153, -154, -183, and -209) in air, floor dust, and product surface dust were measured. While Sigma(8)PBDEs in the air in classrooms showed considerable variations (0.659-1600 pg/m(3), arithmetic mean +/- s.d.: 377 +/- 441 pg/m(3)), those in computer rooms were somewhat similar (134-220 pg/m(3), arithmetic mean +/- s.d.: 169 +/- 40 pg/m(3)). Sigma(8)PBDEs in floor dust varied over a wide range, from 453 to 45,700 ng/g, for all rooms. Based on congener patterns, two groups were created--CL-1 that is dominated by high-brominated congeners and CL-2 primarily comprising low-brominated congeners--for both air and floor dust of classrooms. Surface dust had low concentrations, ranged from ND to 181, from ND to 128, and from ND to 256 pg/cm(2) for desk/chair sets, lockers, and playing tools, respectively. Pearson correlation coefficients were calculated individually for air, floor dust, and surface dust. The results indicate that both surface dust and floor dust may act as a secondary source of PBDEs in indoor environments after emission from facilities. Children have been estimated to have a higher potential exposure to PBDEs than adults. Since children spend most of their day time at school, PBDE distributions in school environments should be a matter of great concern.
NASA Astrophysics Data System (ADS)
Ren, Xinrong; Luke, Winston T.; Kelley, Paul; Cohen, Mark D.; Artz, Richard; Olson, Mark L.; Schmeltz, David; Puchalski, Melissa; Goldberg, Daniel L.; Ring, Allison; Mazzuca, Gina M.; Cummings, Kristin A.; Wojdan, Lisa; Preaux, Sandra; Stehr, Jeff W.
2016-12-01
Different atmospheric mercury forms have been measured at a suburban site in Beltsville, Maryland in the Mid-Atlantic United States since 2007 to investigate their inter-annual, seasonal and diurnal variabilities. Average concentrations and standard deviations of hourly measurements from 2007 to 2015 were 1.41 ± 0.23 ng m-3 for gaseous elemental mercury (GEM), 4.6 ± 33.7 pg m-3 for gaseous oxidized mercury (GOM), and 8.6 ± 56.8 pg m-3 for particulate-bound mercury (PBM). Observations show that on average, the rates of decrease were 0.020 ± 0.007 ng m-3 yr-1 (or 1.3 ± 0.5% yr-1, statistically significant, p-value < 0.01) for GEM, 0.54 ± 0.19 pg m-3 yr-1 (or 7.3 ± 2.6% yr-1, statistically significant, p-value < 0.01) for GOM, and 0.15 ± 0.35 pg m-3 yr-1 (or 1.6 ± 3.8% yr-1, statistically insignificant, p-value > 0.01) for PBM over this nine-year period. In addition, the collocated annual mercury wet deposition decreased at a rate of 0.51 ± 0.24 μg m-2 yr-2 (or 4.2 ± 1.9% yr-1, statistically insignificant, p-value > 0.01). Diurnal variation of GEM shows a slight peak in the morning, likely due to the shallow boundary layer. Seasonal variation of GEM shows lower levels in fall. Both diurnal variations of GOM and PBM show peaks in the afternoon likely due to the photochemical production of reactive mercury from the oxidation of GEM and the influence of boundary layer processes. Seasonally, GOM measurements show high levels in spring and constant low levels in the other three seasons, while PBM measurements exhibit higher levels from late fall to early spring and lower levels from late spring to fall. These measurement data were analyzed using the HYSPLIT back trajectory model in order to examine possible source-receptor relationships at this suburban site. Trajectory frequency analysis shows that high GEM/GOM/PBM events were generally associated with high frequencies of the trajectories passing through areas with high mercury emissions, while low GEM/GOM/PBM levels were largely associated the trajectories passing through relatively clean areas. This study indicates that local and regional sources appear to have a significant impact on the site and these impacts appear to have changed over time, as the local/regional emissions have been reduced.
Impact-driven ocean acidification as a mechanism of the Cretaceous-Palaeogene mass extinction
NASA Astrophysics Data System (ADS)
Ohno, S.; Kadono, T.; Kurosawa, K.; Hamura, T.; Sakaiya, T.; Shigemori, K.; Hironaka, Y.; Sano, T.; Watari, T.; Otani, K.; Matsui, T.; Sugita, S.
2014-12-01
The Cretaceous-Paleogene (K-Pg) mass extinction event at 66 Ma triggered by a meteorite impact is one of the most drastic events in the history of life on the Earth. Many hypotheses have been proposed as killing mechanisms induced by the impact, including global darkness due to high concentrations of atmospheric silicate dust particles, global wildfires, greenhouse warming due to CO2 release, and global acid rain. However, the actual mechanism of extinction remains highly controversial. One of the most important clues for understanding the extinction mechanism is the marine plankton record, which indicates that plankton foraminifera, living in the near-surface ocean, suffered very severe extinction in contrast to the high survival ratio of benthic foraminifera. No proposed extinction mechanism can account for this globally observed marine extinction pattern. Here, we show that SO3-rich impact vapor was released in the K-Pg impact and resulted in the occurrence of global acid rain and sudden severe ocean acidification at the end of the Cretaceous, based on the new results of impact experiments at velocities much higher than previous works (> 10 km/s) and theoretical calculations on aerosol coagulation processes. Sudden severe ocean acidification can account for many of the features of various geologic records at the K?Pg boundary, including severe extinction of plankton foraminifera. This extinction mechanism requires impact degassing of SO3-rich vapor, which is not necessarily found at impact sites other than Chicxulub, suggesting that the degree of mass extinction was controlled greatly by target lithology.
Bauer, T T; Montón, C; Torres, A; Cabello, H; Fillela, X; Maldonado, A; Nicolás, J M; Zavala, E
2000-01-01
The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia. Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested. Serum TNF-alpha levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1beta and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1beta: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1beta: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1beta: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-alpha (standardised coefficient beta = 0.410, p<0.001) and IL-1beta (standardised coefficient beta = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model. Serum TNF-alpha levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-alpha and IL-1beta reflect the severity of the lung injury rather than the diagnosis.
Bauer, T.; Monton, C.; Torres, A.; Cabello, H.; Fillela, X.; Maldonado, A.; Nicolas, J.; Zavala, E.
2000-01-01
BACKGROUND—The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia. METHODS—Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested. RESULTS—Serum TNF-α levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1β and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1β: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1β: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1β: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-α (standardised coefficient β = 0.410, p<0.001) and IL-1β (standardised coefficient β = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model. CONCLUSIONS—Serum TNF-α levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-α and IL-1β reflect the severity of the lung injury rather than the diagnosis. PMID:10607801
Li, Qiangqiang; Zhao, Yan; Zhu, Dan; Pang, Xiumei; Liu, Yue; Frew, Russell; Chen, Gang
2017-06-01
Lipids are very important for human health and milk is a rich dietary source of lipids. In this study, the lipid content in three types of milk (goat, soy and bovine) were determined by using UPLC-Q-Exactive Orbitrap Mass Spectrometry. A total of 13 classes of lipids (including Cer, SM, LPC, PC, PE, DG, TG, PA, PG, PI, PS, LPE, FA) were measured. Moreover, lipid profiles differed significantly between the different milk types. Soymilk is rich in phospholipids including PC, PE, PS, PG, while goat milk is rich in medium chain triglycerides (MCT), USFA, ω-6 FA and ω-3 FA, especially EPA and DHA. Furthermore, a PLS model was established for differentiation of milk types based on the lipid profiles. A total of 14 lipids were identified as biomarkers for differentiation of milk types, thus providing a basis for milk authentication and detection of adulteration. Copyright © 2016 Elsevier Ltd. All rights reserved.
CHCHD10 mutations p.R15L and p.G66V cause motoneuron disease by haploinsufficiency.
Brockmann, Sarah J; Freischmidt, Axel; Oeckl, Patrick; Müller, Kathrin; Ponna, Srinivas K; Helferich, Anika M; Paone, Christoph; Reinders, Jörg; Kojer, Kerstin; Orth, Michael; Jokela, Manu; Auranen, Mari; Udd, Bjarne; Hermann, Andreas; Danzer, Karin M; Lichtner, Peter; Walther, Paul; Ludolph, Albert C; Andersen, Peter M; Otto, Markus; Kursula, Petri; Just, Steffen; Weishaupt, Jochen H
2018-02-15
Mutations in the mitochondrially located protein CHCHD10 cause motoneuron disease by an unknown mechanism. In this study, we investigate the mutations p.R15L and p.G66V in comparison to wild-type CHCHD10 and the non-pathogenic variant p.P34S in vitro, in patient cells as well as in the vertebrate in vivo model zebrafish. We demonstrate a reduction of CHCHD10 protein levels in p.R15L and p.G66V mutant patient cells to approximately 50%. Quantitative real-time PCR revealed that expression of CHCHD10 p.R15L, but not of CHCHD10 p.G66V, is already abrogated at the mRNA level. Altered secondary structure and rapid protein degradation are observed with regard to the CHCHD10 p.G66V mutant. In contrast, no significant differences in expression, degradation rate or secondary structure of non-pathogenic CHCHD10 p.P34S are detected when compared with wild-type protein. Knockdown of CHCHD10 expression in zebrafish to about 50% causes motoneuron pathology, abnormal myofibrillar structure and motility deficits in vivo. Thus, our data show that the CHCHD10 mutations p.R15L and p.G66V cause motoneuron disease primarily based on haploinsufficiency of CHCHD10. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Akhtar, Saeed; Alkatan, Hind M; Kirat, Omar; Khan, Adnan A; Almubrad, Turki
2015-06-01
We report the ultrastructure and 3D transmission electron tomography of collagen fibrils (CFs), proteoglycans (PGs), and microfibrils within the CF of corneas of patients with macular corneal dystrophy (MCD). Three normal corneas and three MCD corneas from three Saudi patients (aged 25, 31, and 49 years, respectively) were used for this study. The corneas were processed for light and electron microscopy studies. 3D images were composed from a set of 120 ultrastructural images using the program "Composer" and visualized using the program "Visuliser Kai". 3D image analysis of MCD cornea showed a clear organization of PGs around the CF at very high magnification and degeneration of the microfibrils within the CF. Within the MCD cornea, the PG area in the anterior stroma was significantly larger than in the middle and posterior stroma. The PG area in the MCD cornea was significantly larger compared with the PG area in the normal cornea. The CF diameter and inter-fibrillar spacing of the MCD cornea were significantly smaller compared with those of the normal cornea. Ultrastructural 3D imaging showed that the production of unsulfated keratin sulfate (KS) may lead to the degeneration of micro-CFs within the CFs. The effect of the unsulfated KS was higher in the anterior stroma compared with the posterior stroma.
Balodis, Iris M; Lacadie, Cheryl M; Potenza, Marc N
2012-09-01
Although self-reported gambling urge intensities have clinical utility in the treatment of pathological gambling (PG), prior studies have not investigated their neural correlates. Functional magnetic resonance imaging (fMRI) was conducted while 10 men with PG and 11 control comparison (CON) men viewed videotaped scenarios of gambling, happy or sad content. Participants rated the intensity of their emotions and motivations and reported the qualities of their responses. Relative to the CON group, the PG group reported similar responses to sad and happy scenarios, but stronger emotional responses and gambling urges when viewing the gambling scenarios. Correlations between self-reported responses and brain activations were typically strongest during the period of reported onset of emotional/motivational response and more robust in PG than in CON subjects for all conditions. During this epoch, corresponding with conscious awareness of an emotional/motivational response, subjective ratings of gambling urges in the PG group were negatively correlated with medial prefrontal cortex activation and positively correlated with middle temporal gyrus and temporal pole activations. Sadness ratings in the PG group correlated positively with activation of the medial orbitofrontal cortex, middle temporal gyrus, and retrosplenial cortex, while self-reported happiness during the happy videos demonstrated largely inverse correlations with activations in the temporal poles. Brain areas identified in the PG subjects have been implicated in explicit, self-referential processing and episodic memory. The findings demonstrate different patterns of correlations between subjective measures of emotions and motivations in PG and CON subjects when viewing material of corresponding content, suggesting in PG alterations in the neural correlates underlying experiential aspects of affective processing.
Lacadie, Cheryl M.; Potenza, Marc N.
2011-01-01
Although self-reported gambling urge intensities have clinical utility in the treatment of pathological gambling (PG), prior studies have not investigated their neural correlates. Functional magnetic resonance imaging (fMRI) was conducted while 10 men with PG and 11 control comparison (CON) men viewed videotaped scenarios of gambling, happy or sad content. Participants rated the intensity of their emotions and motivations and reported the qualities of their responses. Relative to the CON group, the PG group reported similar responses to sad and happy scenarios, but stronger emotional responses and gambling urges when viewing the gambling scenarios. Correlations between self-reported responses and brain activations were typically strongest during the period of reported onset of emotional/motivational response and more robust in PG than in CON subjects for all conditions. During this epoch, corresponding with conscious awareness of an emotional/motivational response, subjective ratings of gambling urges in the PG group were negatively correlated with medial prefrontal cortex activation and positively correlated with middle temporal gyrus and temporal pole activations. Sadness ratings in the PG group correlated positively with activation of the medial orbitofrontal cortex, middle temporal gyrus, and retrosplenial cortex, while self-reported happiness during the happy videos demonstrated largely inverse correlations with activations in the temporal poles. Brain areas identified in the PG subjects have been implicated in explicit, self-referential processing and episodic memory. The findings demonstrate different patterns of correlations between subjective measures of emotions and motivations in PG and CON subjects when viewing material of corresponding content, suggesting in PG alterations in the neural correlates underlying experiential aspects of affective processing. PMID:21811809
Estimates of Gelatinous Zooplankton Carbon Flux in the Global Oceans
NASA Astrophysics Data System (ADS)
Luo, J. Y.; Condon, R.; Cowen, R. K.
2016-02-01
Gelatinous zooplankton (GZ), which include the cnidarians, ctenophores, and pelagic tunicates, are a common feature of marine ecosystems worldwide, but their contribution to global biogeochemical fluxes has never been assessed. We constructed a carbon-cycle model with a single, annual time-step and resolved to a 5° spatial grid for the three major GZ groups in order to evaluate the GZ-mediated carbon fluxes and export to depth. Biomass inputs (totaling 0.149 Pg C) were based off of Lucas et al. (2014) and updated using the JeDI database (Condon et al. 2015). From the upper ocean, biomass export flux from cnidarians, ctenophores, and tunicates totaled 2.96 ± 2.82 Pg C y-1, though only 0.199 ± 0.023 Pg C y-1 of GZ carbon were transferred to upper trophic levels, roughly amounting to one-quarter of all mesozooplankton production flux. In contrast, GZ fluxes to DOC only comprised ca. 2% of labile DOC flux. Egestion flux from the upper ocean totaled 2.56 ± 3.35 Pg C y-1, with over 80% being fast-sinking tunicate fecal pellets. Due to fast sinking rates of carcasses and fecal pellets, 26% of all C export from the upper ocean reached the seafloor, such that GZ fecal matter is estimated to comprise between 20-30% of global POC surface export and 11-30% of POC seafloor deposition. Finally, results from sensitivity analyses showed no increase in cnidarian and ctenophore export fluxes with increased temperature and jelly biomass, though tunicate export fluxes showed some increase with both temperature and biomass. These results suggest that current estimates of global POC flux from the surface oceans, which range between 8.6 - 12.9 Pg C y-1, may be underestimated by as much as 20 - 25%, implying a definite need to incorporate GZ mediated flux in estimating the biological pump transfer efficiency. Our study represents the first effort to quantify the role of gelatinous zooplankton in the global marine carbon cycle.
Pastor, Lucía; Casellas, Aina; Carrillo, Jorge; Maculuve, Sonia; Jairoce, Chenjerai; Paredes, Roger; Blanco, Julià; Naniche, Denise
2017-01-01
Abstract Background Achieving effective antiretroviral treatment (ART) monitoring is a key determinant to ensure viral suppression and reach the UNAIDS 90-90-90 targets. The gold standard for detecting virological failure is plasma human immunodeficiency virus (HIV) RNA (viral load [VL]) testing; however, its availability is very limited in low-income countries due to cost and operational constraints. Methods HIV-1–infected adults on first-line ART attending routine visits at the Manhiça District Hospital, Mozambique, were previously evaluated for virologic failure. Plasma levels of interferon-γ–inducible protein 10 (IP-10) were quantified by enzyme-linked immunosorbent assay. Logistic regression was used to build an IP-10–based model able to identify individuals with VL >150 copies/mL. From the 316 individuals analyzed, 253 (80%) were used for model training and 63 (20%) for validation. Receiver operating characteristic curves were employed to evaluate model prediction. Results From the individuals included in the training set, 34% had detectable VL. Mean age was 41 years, 70% were females, and median time on ART was 3.4 years. IP-10 levels were significantly higher in subjects with detectable VL (108.2 pg/mL) as compared to those with undetectable VL (38.0 pg/mL) (P < .0001, U test). IP-10 univariate model demonstrated high classification performance (area under the curve = 0.85 [95% confidence interval {CI}, .80–.90]). Using a cutoff value of IP-10 ≥44.2 pg/mL, the model identified detectable VL with 91.9% sensitivity (95% CI, 83.9%–96.7%) and 59.9% specificity (95% CI, 52.0%–67.4%), values confirmed in the validation set. Conclusions IP-10 is an accurate biomarker to screen individuals on ART for detectable viremia. Further studies should evaluate the benefits of IP-10 as a triage approach to monitor ART in resource-limited settings. PMID:29020145
Gu, Min-Jung; Jeon, Ji-Hyun; Oh, Myung Sook; Hong, Seon-Pyo
2016-01-01
We developed a method to detect biogenic amines and their metabolites in rat brain tissue using simultaneous high-performance liquid chromatography and a photodiode array detection. Measurements were made using a Hypersil Gold C-18 column (250 × 2.1 mm, 5 µm). The mobile phase was 5 mM perchloric acid containing 5 % acetonitrile. The correlation coefficient was 0.9995-0.9999. LODs (S/N = 3) and LOQs (S/N = 10) were as follows: dopamine 0.4 and 1.3 pg, 3, 4-dihydroxyphenylacetic acid 8.4 and 28.0 pg, serotonin 0.4 and 1.3 pg, 5-hydroxyindolacetic acid 3.4 and 11.3 pg, and homovanillic acid 8.4 and 28.0 pg. This method does not require derivatization steps, and is more sensitive than the widely used HPLC-UV method.
Conversion of 1,3-Propylene Glycol on Rutile TiO2(110)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Long; Li, Zhenjun; Smith, R. Scott
2014-10-09
The adsorption of 1,3-propylene glycol (1,3-PG) on partially reduced TiO2(110) and its conversion to products have been studied by a combination of molecular beam dosing and temperature programmed desorption (TPD). When the Ti surface sites are saturated by 1,3-PG, ~80% of the molecules undergo further reactions to yield products that are liberated during the TPD ramp. In contrast to ethylene glycol (EG) and 1,2- propylene glycol (1,2-PG) that yield only alkenes and water at very low coverages (< 0.05 ML), two additional products, HCHO and C2H4, along with propylene (CH3CHCH2) and water are observed for 1,3-PG. Identical TPD line shapesmore » and desorption yields for HCHO and C2H4 suggest that these products result from C-C bond cleavage and are coupled. At higher 1,3-PG coverages (> 0.1 ML), propanal (CH3CH2CHO) and two additional products, 1-propanol (CH3CH2CH2OH) and acrolein (CH2CHCHO), are observed. The desorption of 1-propanol is found to be coupled with the desorption of acrolein, suggesting that these products are formed by the disproportionation of two 1,3-PG molecules. The coverage dependent TPD results further show that propylene formation dominates at low coverages (< 0.3 ML), while the decomposition and disproportionation channels increase rapidly at higher coverages and reach yields comparable to that of propylene at the 1,3-PG saturation coverage of 0.5 ML. The observed surface chemistry clearly shows how the molecular structure of glycols influences their reaction pathways on oxide surfaces.« less
Bekar, Özlem; Shahmoon-Shanok, Rebecca; Steele, Miriam; Levy, Jaclyn; deFressine, Lauren; Giuseppone, Katie; Steele, Howard
2017-01-01
Risk factors during preschool years, such as poverty and unattended social/emotional problems, are known to have a strong negative influence on children's later functioning. This study aimed to investigate the effectiveness of an on-site integrated school-based mental health services and consultation program for preschool children and their families. The sample consisted of 47 children and parents in 3 childcare centers who came from low-socioeconomic, urban backgrounds. Parents provided questionnaire data on children's social-emotional functioning at 2 assessment times. Children's ages ranged between 2 and 4 years at Time 1. Approximately half of the sample consisted of children who were selected for and received twice-weekly peer play psychotherapy (PPP) and, at-times, other mental health services from clinicians (playgroup [PG] children). The other half of the sample consisted of better functioning non-playgroup (NPG) children from the same centers. When PG and NPG were compared at Time1, the PG children were significantly behind the NPG children justifying their assignment to PG. However, at Time 2, the difference between PG and NPG was no longer significant on vital measures of adaptation, revealing the ways in which Relationships for Growth & Learning (RfGL) Program arguably led to 'catch up'. PG children's behavioral problems and total symptomatology decreased significantly from Time 1 to Time 2. Higher dosage of PPP was linked with higher social competence and decreased behavioral problems. Areas of gain differed between internalizing and externalizing children, indicating that intervention was helpful to different types of children. Clinical and research implications were discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Ohhara, Yuya; Shimada-Niwa, Yuko; Niwa, Ryusuke; Kayashima, Yasunari; Hayashi, Yoshiki; Akagi, Kazutaka; Ueda, Hitoshi; Yamakawa-Kobayashi, Kimiko; Kobayashi, Satoru
2015-02-03
In Drosophila, pulsed production of the steroid hormone ecdysone plays a pivotal role in developmental transitions such as metamorphosis. Ecdysone production is regulated in the prothoracic gland (PG) by prothoracicotropic hormone (PTTH) and insulin-like peptides (Ilps). Here, we show that monoaminergic autocrine regulation of ecdysone biosynthesis in the PG is essential for metamorphosis. PG-specific knockdown of a monoamine G protein-coupled receptor, β3-octopamine receptor (Octβ3R), resulted in arrested metamorphosis due to lack of ecdysone. Knockdown of tyramine biosynthesis genes expressed in the PG caused similar defects in ecdysone production and metamorphosis. Moreover, PTTH and Ilps signaling were impaired by Octβ3R knockdown in the PG, and activation of these signaling pathways rescued the defect in metamorphosis. Thus, monoaminergic autocrine signaling in the PG regulates ecdysone biogenesis in a coordinated fashion on activation by PTTH and Ilps. We propose that monoaminergic autocrine signaling acts downstream of a body size checkpoint that allows metamorphosis to occur when nutrients are sufficiently abundant.
Comparison of Glaucoma Progression Detection by Optical Coherence Tomography and Visual Field.
Zhang, Xinbo; Dastiridou, Anna; Francis, Brian A; Tan, Ou; Varma, Rohit; Greenfield, David S; Schuman, Joel S; Huang, David
2017-12-01
To compare longitudinal glaucoma progression detection using optical coherence tomography (OCT) and visual field (VF). Validity assessment. We analyzed subjects with more than 4 semi-annual follow-up visits (every 6 months) in the multicenter Advanced Imaging for Glaucoma Study. Fourier-domain optical coherence tomography (OCT) was used to map the thickness of the peripapillary retinal nerve fiber layer (NFL) and ganglion cell complex (GCC). OCT-based progression detection was defined as a significant negative trend for either NFL or GCC. VF progression was reached if either the event or trend analysis reached significance. The analysis included 356 glaucoma suspect/preperimetric glaucoma (GS/PPG) eyes and 153 perimetric glaucoma (PG) eyes. Follow-up length was 54.1 ± 16.2 months for GS/PPG eyes and 56.7 ± 16.0 for PG eyes. Progression was detected in 62.1% of PG eyes and 59.8% of GS/PPG eyes by OCT, significantly (P < .001) more than the detection rate of 41.8% and 27.3% by VF. In severity-stratified analysis of PG eyes, OCT had significantly higher detection rate than VF in mild PG (63.1% vs. 38.7%, P < .001), but not in moderate and advanced PG. The rate of NFL thinning slowed dramatically in advanced PG, but GCC thinning rate remained relatively steady and allowed good progression detection even in advanced disease. The Kaplan-Meier time-to-event analyses showed that OCT detected progression earlier than VF in both PG and GS/PPG groups. OCT is more sensitive than VF for the detection of progression in early glaucoma. While the utility of NFL declines in advanced glaucoma, GCC remains a sensitive progression detector from early to advanced stages. Copyright © 2017 Elsevier Inc. All rights reserved.
Atmospheric input of N, P, Fe and trace metals to north Indian Ocean
NASA Astrophysics Data System (ADS)
Sarin, Manmohan; Srinivas, Bikkina
2016-04-01
The air-sea deposition of chemical constituents to the north Indian Ocean is influenced by seasonal continental outflow during the late NE-monsoon (December-April). Our recent studies have focused on deposition of mineral dust, nutrients (N, P and Fe) and toxic trace metals to the Arabian Sea (ARS) and Bay of Bengal (BoB), two important limbs of the north Indian Ocean. The chemical composition of PM2.5 in the continental outflow to the marine atmospheric boundary layer reveals dominance of nss-SO42- (as high as 25 μg m-3) and abundance of dust varies from 3 to 20 μg m-3. A striking similarity in the temporal variability of total inorganic acidity (TIA = NO3- + nss-SO42-) and fractional solubility of aerosol-Fe (FeTot: 60 - 1145 ng m-3) provides evidence for chemical processing of mineral dust during atmospheric transport. The enhanced solubility of Fe has implications to further increase in the deposition of this micro-nutrient to ocean surface. The mass ratio of nutrients (NInorg/NTot, Norg/NTot and PInorg/nss-Ca2+) also suggests further increase in their air-sea deposition to the surface BoB. The dry-deposition flux of PInorgto BoB varies by one order of magnitude (0.5 - 5.0 μmol-P m-2 d-1; Av: 0.02 Tg P yr-1). Based on atmospheric deposition of P and Fe, C-fixation in BoB (˜1 Pg yr-1) is dominated by anthropogenic sources and that in ARS (0.3 Pg yr-1) is limited by P and Fe. This is attributed to poor fractional solubility (˜1%) of mineral dust over the Arabian Sea. However, N-fixation by diazotrophs in the two oceanic regions is somewhat similar (0.03 Pg yr-1). Our estimate of N-deposition (0.2 Tg yr-1) to the northern Indian Ocean is significantly lower than the model results (˜800 - 1200 mg-N m-2 yr-1 ≈ 5.7 - 8.6 Tg yr-1 by Duce et al. (2008); ˜4.1 Tg yr-1 by Okin et al. (2011); and ˜0.8 Tg yr-1 by Kanakidou et al. (2012). The increase in aerosol toxicity is also evident from high enrichment factors of anthropogenic trace metal (Pb, Cd, Cr, Cu and Mn). The enhanced solubility of anthropogenic fractions of trace metals, relative to their dust derived component, is an important issue for assessing factors that influence the marine ecosystem in the north Indian Ocean.
Resistance Phenotypes Mediated by Aminoacyl-Phosphatidylglycerol Synthases
Arendt, Wiebke; Hebecker, Stefanie; Jäger, Sonja; Nimtz, Manfred
2012-01-01
The specific aminoacylation of the phospholipid phosphatidylglycerol (PG) with alanine or with lysine catalyzed by aminoacyl-phosphatidylglycerol synthases (aaPGS) was shown to render various organisms less susceptible to antibacterial agents. This study makes use of Pseudomonas aeruginosa chimeric mutant strains producing lysyl-phosphatidylglycerol (L-PG) instead of the naturally occurring alanyl-phosphatidylglycerol (A-PG) to study the resulting impact on bacterial resistance. Consequences of such artificial phospholipid composition were studied in the presence of an overall of seven antimicrobials (β-lactams, a lipopeptide antibiotic, cationic antimicrobial peptides [CAMPs]) to quantitatively assess the effect of A-PG substitution (with L-PG, L-PG and A-PG, increased A-PG levels). For the employed Gram-negative P. aeruginosa model system, an exclusive charge repulsion mechanism does not explain the attenuated antimicrobial susceptibility due to PG modification. Additionally, the specificity of nine orthologous aaPGS enzymes was experimentally determined. The newly characterized protein sequences allowed for the establishment of a significant group of A-PG synthase sequences which were bioinformatically compared to the related group of L-PG synthesizing enzymes. The analysis revealed a diverse origin for the evolution of A-PG and L-PG synthases, as the specificity of an individual enzyme is not reflected in terms of a characteristic sequence motif. This finding is relevant for future development of potential aaPGS inhibitors. PMID:22267511
The role of arginine vasopressin in electroacupuncture treatment of primary sciatica in human.
Zhao, Xue-Yan; Zhang, Qi-Shun; Yang, Jun; Sun, Fang-Jie; Wang, Da-Xin; Wang, Chang-Hong; He, Wei-Ya
2015-08-01
It has been implicated that electroacupuncture can relieve the symptoms of sciatica with the increase of pain threshold in human, and arginine vasopressin (AVP) in the brain rather than the spinal cord and blood circulation participates in antinociception. Our previous study has proven that AVP in the brain played a role in the process of electroacupuncture analgesia in rat. The goal of the present study was to investigate the role of AVP in electroacupuncture in treating primary sciatica in human. The results showed that (1) AVP concentration of cerebrospinal fluid (CSF) (7.5 ± 2.5 pg/ml), not plasma (13.2 ± 4.2 pg/ml) in primary sciatica patients was lower than that in health volunteers (16.1 ± 3.8 pg/ml and 12.3 ± 3.4 pg/ml), although the osmotic pressure in CSF and plasma did not change; (2) electroacupuncture of the bilateral "Zusanli" points (St. 36) for 60 min relieved the pain sensation in primary sciatica patients; (3) electroacupuncture increased the AVP level of CSF, not plasma in primary sciatica patients; and (4) there was the positive correlation between the effect of electroacupuncture relieving the pain and the AVP level of CSF in the primary sciatica patients. The data suggested that central AVP, not peripheral AVP might improve the effect of electroacupuncture treatment of primary sciatica in human, i.e., central AVP might take part in the electroacupuncture relieving the pain sensation in primary sciatica patients. Copyright © 2015 Elsevier B.V. All rights reserved.
Fiorentino, T V; Hribal, M L; Perticone, M; Andreozzi, F; Sciacqua, A; Perticone, F; Sesti, G
2015-04-01
We aimed to evaluate the inflammatory profile of individuals with prediabetes defined by HbA1c levels, according to the new American Diabetes Association criteria, and to determine the ability of HbA1c to identify individuals with subclinical inflammation independently of the contribution of other metabolic parameters such as fasting, 1- or 2-h post-load glucose (PG) levels. High sensitivity C-reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), fibrinogen, white blood cells (WBC) count and complement C3 (C3) were assessed, and oral glucose tolerance test (OGTT) was performed in 711 adults. Subjects were stratified into three groups according to their HbA1c levels. Poor agreement existed between HbA1c and 2-h PG criteria for identification of individuals with prediabetes (κ coefficient = 0.300). As compared with subjects having HbA1c <5.7 % (39 mmol/mol), individuals with prediabetes (HbA1c 5.7-6.4 %, [39-46 mmol/mol]) exhibited a significant increase of the concentration of five inflammatory markers (hsCRP, ESR, fibrinogen, WBC count, C3) as well as of a cluster of inflammatory markers, as measured by an inflammatory score after adjusting for sex, age, smoking, fasting, 1- and 2-h PG levels. In multiple regression models including sex, age, body mass index, smoking habit, fasting, 1- and 2-h PG levels, and HOMA index, HbA1c levels were significant independent contributors to each of the five inflammatory markers examined. These data suggest that HbA1c is a reliable marker of glucose homeostasis, and may identify individuals at increased risk of diabetes with unfavorable inflammatory profile independently from fasting and 2-h PG levels.
Ren, Hong; Ren, Guoli; Sun, Limin; Fan, Xiuhua; Wang, Yuran; Li, Xiaoxi
2015-05-01
To investigate the production and mechanism of chemokine (C-C motif) ligand 5 (CCL5) by macrophages in U14 cervical cancer-bearing mice during infection. The U14 cervical cancer cells were injected in C57BL/6 mice to induce tumor-bearing condition. Lipopolysaccharide (LPS) was injected into C57BL/6 mice to induce infection. The protein expression of CCL5 in the serum and the CCL5 mRNA expression in inflammatory cells were measured by ELISA and fluorescence quantitative-PCR in four groups. Macrophages were induced in the tumor conditioned medium (TCM) which extracted from mice serum. The protein expression levels of CCL5, prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP) in the medium and CCL5, PGE2 and cAMP mRNA expression in the macrophages were detected in different groups. In order to determine whether the inhibition was related to PGE2, selective cyclooxygenase 2(COX-2) inhibitor NS398 was used to reverse this phenomenon and protein kinase A (PKA) inhibitor H89 demonstrated the mechanism through blocking cAMP/PKA signaling pathway. (1) The protein and mRNA level of CCL5 in tumor-bearing mice were respectively (151 ± 35) pg/ml and 1.0, which were lower than those in the tumor-free mice (691 ± 85) pg/ml and 4.5 ± 0.8, there were significant difference between them (all P < 0.05). The protein and mRNA level of PGE2 in tumor-bearing mice were (1 198 ± 83) pg/ml and 5.8 ± 0.8, which were higher than those in the tumor-free mice (187 ± 25) pg/ml and 1.0, the difference were significant (all P < 0.05). The protein and mRNA level of CCL5 in tumor-free + LPS mice were (4 049 ± 141) pg/ml and 31.5 ± 2.0, which were higher than those in the tumor-bearing + LPS mice (1 951 ± 71) pg/ml and 12.1 ± 2.8, the difference were also significant (P < 0.05). The protein and mRNA level of PGE2 in tumor-free + LPS mice were (676 ± 70) pg/ml and 3.4 ± 0.4, which were lower than those in tumor-bearing + LPS mice (2 550 ± 382) pg/ml and 11.6 ± 0.9, the difference were also significant (all P < 0.05). (2) Macrophages were cultured in vitro using TCM derived from mice. The protein and mRNA level of CCL5 in tumor-bearing mice TCM were respectively (1 626 ± 177) pg/ml and 28.6 ± 1.2, which were higher than those in the tumor-free mice TCM [(27 ± 3) pg/ml and 1.0], there were significant difference (P < 0.05). The protein and mRNA level of PGE2 in tumor-bearing mice TCM were (790 ± 156) pg/ml and 1.7 ± 0.3, which were higher than those in the tumor-free mice TCM [(448 ± 115) pg/ml, 1.0], the difference were significant (all P < 0.05). The protein and mRNA level of cAMP in tumor-bearing mice TCM were (164 ± 30) pg/ml and 1.6 ± 0.3, which weres higher than those in the tumor-free mice TCM [(118 ± 25) pg/ml,1.0], the difference were significant (all P < 0.05). The protein and mRNA level of CCL5 in tumor-free + LPS mice TCM were (10 475 ± 742) pg/ml and 212.0 ± 5.7, which were higher than those in the tumor-bearing + LPS mice TCM [(6 375 ± 530) pg/ml, 142.3 ± 2.5], the difference were significant (all P < 0.05). The protein and mRNA level of PGE2 in tumor-free + LPS mice TCM were (2 438 ± 95) pg/ml and 4.3 ± 0.7, which weres lower than those in the tumor-bearing + LPS mice TCM [(3 441 ± 163) pg/ml, 5.9 ± 0.3], the difference were significant (all P < 0.05). The protein and mRNA level of cAMP in tumor-free + LPS mice TCM were (340 ± 13) pg/ml and 4.1 ± 0.4, which were lower than those in the tumor-bearing + LPS mice TCM [(542 ± 42) pg/ml, 5.4 ± 0.5], the difference were significant (all P < 0.05). (3) Using COX-2 inhibitor NS398 in the tumor-bearing + LPS mice, the protein and mRNA level of CCL5, PGE2 and cAMP were (7 691 ± 269) pg/ml and 159.0 ± 8.9, (2 820 ± 152) pg/ml and 4.9 ± 0.3, (465 ± 8) pg/ml and 4.3 ± 0.4, respectively, and there were significant difference (all P < 0.05), compared to before treatment. Using PKA inhibitor H89 in the tumor-bearing + LPS mice, the protein and mRNA level of CCL5, PGE2 and cAMP were (8 375 ± 520) pg/ml and 177.0 ± 8.8, (2 650 ± 35) pg/ml and 4.7 ± 0.4, (368 ± 13) pg/ml and 3.1 ± 0.7, respectively, and there were significant difference (all P < 0.05), compared to before treatment. TCM of U14 cells activated macrophages to release PGE2 could inhibit the expression of CCL5 levels by cAMP/PKA signaling pathway.
Shi, Ying; Gan, Lei; Li, Xibing; He, Suya; Sun, Cheng; Gao, Li
2018-02-01
Phosphate rock in Guiyang (Southwest of China) is used for the phosphate production, and hence generating a by-product phosphogypsum (PG). From 2007, part of the PG was used as main raw material for cemented backfill. The main objective of this paper is to investigate the geochemical evolution of metals before and after the PG inclusion into the backfill matrix. A sequential extraction procedure was selected to determine the chemical speciation of metals in phosphate rock, PG, binder and field backfill samples. Dynamics of metals going from phosphate rock and PG to backfill have been evaluated. The results showed that almost all the metals in the PG and binder had been effectively transferred to the backfill. Furthermore, compared to metals taken out along with phosphate rock exploitation, PG-based cemented backfill might bring some metals back but with only little metals in mobile fraction. Additionally, in order to determine the long-term behavior of metals in PG-based cemented backfill, the field samples which were backfilled from 2007 to 2016 were collected and analyzed. The results showed that total amounts of metals in backfill were all within similar range, indicating that the cemented PG backfill could be an effective method to solidify/stabilize metals in PG. Nevertheless, Due to the high water-soluble fractions detected, the concentrations of As, Mn and Zn should be continuously monitored. Copyright © 2017. Published by Elsevier Ltd.
Mixing with propylene glycol enhances the bond strength of mineral trioxide aggregate to dentin.
Salem Milani, Amin; Froughreyhani, Mohammad; Charchi Aghdam, Saeed; Pournaghiazar, Fatemeh; Asghari Jafarabadi, Mohammad
2013-11-01
Mixing mineral trioxide aggregate (MTA) with different proportions of propylene glycol (PG) improves its handling property. The aim of this study was to evaluate the effect of PG on MTA-dentin push-out bond strength. Seventy-five 2-mm-thick midroot sections were prepared from single-rooted human extracted teeth. The lumen of each slice was enlarged with Gates-Glidden burs. The slices were randomly divided into 3 groups (n = 25). In each group, 0.3 mL of the liquid was mixed with 1 g MTA (Angelus, Londrina, Brazil). The liquid vehicles used in groups 1-3 were 100% distilled water (DW), 20% PG-80% DW, and 100% PG, respectively. After incubation, the push-out strength of the samples was measured using a universal testing machine. The samples were then cut in halves and examined under a stereomicroscope to determine the failure pattern. One-way analysis of variance followed by the Tukey post hoc test was used to compare the push-out strength among groups. There were statistically significant differences between groups (P < .001). The push-out strength in group 1 (DW) was significantly lower than groups 2 and 3 (P < .001 and P = .022, respectively). However, there was no significant difference between groups 2 (DW-PG) and 3 (PG). Mixing MTA with PG increased its push-out bond strength to dentin. In the present study, the most suitable ratio was 80% DW-20% PG. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Yang, Min; Wang, Guang Ji; Wang, Su Jun; Li, Xiao Tian; Xu, Yu Ping; Wang, Song Pei; Xiang, Jing De; Pan, Shang Ren; Cao, Guo Xian; Ye, Wen Cai
2005-01-01
23-Hydroxybetulinic acid is a newly isolated derivative of betulinic acid. The agent exhibits potential anti-tumor activity and functions in this regard via apoptosis. In support of pharmacokinetic and toxicological evaluations, a new assay based on liquid chromatography/mass spectrometry (LC/MS) was developed for the quantitative analysis of 23-hydroxybetulinic acid. Sample preparation consisted of extraction of the plasma by the addition of methylene chloride followed by centrifugation. Aliquots of the supernatant were analyzed using an isocratic reversed-phase high-performance liquid chromatography (HPLC) system coupled to a negative ion electrospray mass spectrometer. Molecules of 23-hydroxybetulinic acid and the internal standard limonin were detected using selected ion monitoring at m/z 471 and 469, respectively. The limit of detection of 23-hydroxybetulinic acid was 0.05 pg (0.11 fmol) injected on-column (10 pg/mL, 5 microL injection volume), and the limit of quantitation was 10 pg (21.19 fmol, 2 ng/mL, 5 muL injection volume). 23-Hydroxybetulinic acid was stable in plasma samples at -20 degrees C for at least 3 weeks. The intra-day and inter-day coefficients of variation of the assay were 3.0 and 4.8%, respectively. The utility of the assay was demonstrated by measuring 23-hydroxybetulinicacid in mouse plasma following intragastric administration (IG) in vivo. Pharmacokinetic parameters were calculated using the 3P97 pharmacokinetic software package. A two-compartment, first-order model was selected for pharmacokinetic modeling. The result showed that after IG of 200 mg/kg 23-hydroxybetulinic acid, the plasma concentrations reached peaks at 2 h with C(max) of 3.1 microg/mL. The 200 mg/kg 23-hydroxybetulinic acid suspension IG doses were found to have long elimination half-lives of 25.6 h and low bioavailability of 2.3%. No interference was noted due to endogenous substances. These analytical methods should be of value in future studies related to the development and characterization of 23-hydroxybetulinic acid. Copyright 2005 John Wiley & Sons, Ltd.
Malecka, Kamila; Michalczuk, Lech; Radecka, Hanna; Radecki, Jerzy
2014-10-09
A DNA biosensor for detection of specific oligonucleotides sequences of Plum Pox Virus (PPV) in plant extracts and buffer is proposed. The working principles of a genosensor are based on the ion-channel mechanism. The NH2-ssDNA probe was deposited onto a glassy carbon electrode surface to form an amide bond between the carboxyl group of oxidized electrode surface and amino group from ssDNA probe. The analytical signals generated as a result of hybridization were registered in Osteryoung square wave voltammetry in the presence of [Fe(CN)6]3-/4- as a redox marker. The 22-mer and 42-mer complementary ssDNA sequences derived from PPV and DNA samples from plants infected with PPV were used as targets. Similar detection limits of 2.4 pM (31.0 pg/mL) and 2.3 pM (29.5 pg/mL) in the concentration range 1-8 pM were observed in the presence of the 22-mer ssDNA and 42-mer complementary ssDNA sequences of PPV, respectively. The genosensor was capable of discriminating between samples consisting of extracts from healthy plants and leaf extracts from infected plants in the concentration range 10-50 pg/mL. The detection limit was 12.8 pg/mL. The genosensor displayed good selectivity and sensitivity. The 20-mer partially complementary DNA sequences with four complementary bases and DNA samples from healthy plants used as negative controls generated low signal.
NASA Technical Reports Server (NTRS)
Houghton, R. A.
1998-01-01
The general purpose of this research was to improve and update (to 1990) estimates of the net flux of carbon between the world's terrestrial ecosystems and the atmosphere from changes in land use (e.g., deforestation and reforestation). The estimates are important for understanding the global carbon cycle, and for predicting future concentrations of atmospheric CO2 that will result from emissions. The emphasis of the first year's research was on the northern temperate zone and boreal forests, where the greatest discrepancy exists between estimates of flux. Forest inventories suggest net sinks of 0.6 PgC/yr; inversion analyses based on atmospheric data and models suggest much larger sinks 2-3.6 PgC/yr (e.g., Tans et al. 1990, Ciais et al. 1995). The work carried out with this grant calculated the flux attributable to changes in land use. The estimated flux was somewhat smaller than the flux calculated from inventory data suggesting that environmental changes have led to a small accumulation of carbon in forests that exceeds the accumulation expected from past rates of harvest. Two publications have described these results (Houghton 1996, 1998). The large difference between these estimates and those obtained with atmospheric data and models remains unexplained. The recent estimate of a 1.7 PgC/yr sink in North America, alone (Fan et al. 1998), is particularly difficult to explain. That part of the sink attributable to land-use change, however, is defined as a result of this grant.
Gao, Aichao; Wang, Xichao; Yu, Haiyan; Li, Na; Hou, Yubo; Yu, Weixian
2016-02-01
Porphyromonas gingivalis (Pg) as the major pathogenic bacterium of chronic periodontitis can cause alveolar bone resorption. Lipopolysaccharide (LPS) is its main virulence factor. The Eph family plays an important role in maintaining bone homeostasis. In this study, the effects of P. gingivalis lipopolysaccharide (Pg-LPS) on the expression of EphA2 in osteoblasts and osteoclasts were investigated. MC3T3-E1 cells and RAW264.7 cells were separately cultured in osteoblast-conditioned medium and osteoclast-conditioned medium to induce their differentiation into osteoblasts and osteoclasts, respectively. MC3T3-E1 cells were treated with 1 μg/mL of Pg-LPS 3, 7, and 14 d later, while RAW264.7 cells were treated with 10 μg/mL of Pg-LPS 1, 3, and 5 d later. The results have shown that Pg-LPS increased the expression of EphA2 both in osteoblasts and osteoclasts, decreased the expression of osteogenic-related genes (ALP, Sp7), and increased the expression of osteoclast-related genes (MMP9, c-fos, ACP5, CtsK, and NFATc1). Tartrate-resistant acid phosphatase (TRAP) staining illustrated that Pg-LPS promoted osteoclast differentiation and decreased the activity of alkaline phosphatase. Therefore, analysis indicates that, when treated with Pg-LPS, the expression of EphA2 is upregulated while the activity of osteoblasts and osteoclasts was reduced and increased, respectively. Our data suggest that EphA2 is closely related to the formation of osteoblasts and resorption of osteoclast and is likely to play an role in bone resorption induced in chronic periodontitis. These findings may provide information on new targets for prevention and treatment of chronic periodontitis.
Lin, Yun; Melby, Daniel P; Krishnan, Balaji; Adabag, Selcuk; Tholakanahalli, Venkatakrishna; Li, Jian-Ming
2017-08-01
The aim of this study is to investigate the frequency of electrosurgery-related pacemaker malfunction. A retrospective study was conducted to investigate electrosurgery-related pacemaker malfunction in consecutive patients undergoing pulse generator (PG) replacement or upgrade from two large hospitals in Minneapolis, MN between January 2011 and January 2014. The occurrence of this pacemaker malfunction was then studied by using MAUDE database for all four major device vendors. A total of 1398 consecutive patients from 2 large tertiary referral centers in Minneapolis, MN undergoing PG replacement or upgrade surgery were retrospectively studied. Four patients (0.3% of all patients), all with pacemakers from St Jude Medical (2.8%, 4 of 142) had output failure or inappropriately low pacing rate below 30 bpm during electrosurgery, despite being programmed in an asynchronous mode. During the same period, 1174 cases of pacemaker malfunctions were reported on the same models in MAUDE database, 37 of which (3.2%) were electrosurgery-related. Twenty-four cases (65%) had output failure or inappropriate low pacing rate. The distribution of adverse events was loss of pacing (59.5%), reversion to backup pacing (32.4%), inappropriate low pacing rate (5.4%), and ventricular fibrillation (2.7%). The majority of these (78.5%) occurred during PG replacement at ERI or upgrade surgery. No electrosurgery-related malfunction was found in MAUDE database on 862 pacemaker malfunction cases during the same period from other vendors. Electrosurgery during PG replacement or upgrade surgery can trigger output failure or inappropriate low pacing rate in certain models of modern pacemakers. Cautions should be taken for pacemaker-dependent patients.
Rafique, Rashid; Zhao, Fang; de Jong, Rogier; ...
2016-02-25
The net primary productivity (NPP) is commonly used for understanding the dynamics of terrestrial ecosystems and their role in carbon cycle. We used a combination of the most recent NDVI and model–based NPP estimates (from five models of the TRENDY project) for the period 1982-2012, to study the role of terrestrial ecosystems in carbon cycle under the prevailing climate conditions. We found that 80% and 67% of the global land area showed positive NPP and NDVI values, respectively, for this period. The global NPP was estimated to be about 63 Pg C y -1, with an increase of 0.214 Pgmore » C y -1 y -1. Similarly, the global mean NDVI was estimated to be 0.33, with an increasing trend of 0.00041 y-1. The spatial patterns of NPP and NDVI demonstrated substantial variability, especially at the regional level, for most part of the globe. However, on temporal scale, both global NPP and NDVI showed a corresponding pattern of increase (decrease) for the duration of this study except for few years (e.g. 1990 and 1995-98). Generally, the Northern Hemisphere showed stronger NDVI and NPP increasing trends over time compared to the Southern Hemisphere; however, NDVI showed larger trends in Temperate regions while NPP showed larger trends in Boreal regions. Among the five models, the maximum and minimum NPP were produced by JULES (72.4 Pg C y -1) and LPJ (53.72 Pg C y -1) models, respectively. At latitudinal level, the NDVI and NPP ranges were ~0.035 y -1 to ~-0.016 y -1 and ~0.10 Pg C y -1 y -1 to ~-0.047 Pg C y -1 y -1, respectively. Overall, the results of this study suggest that the modeled NPP generally correspond to the NDVI trends in the temporal dimension. Lastly, the significant variability in spatial patterns of NPP and NDVI trends points to a need for research to understand the causes of these discrepancies between molded and observed ecosystem dynamics, and the carbon cycle.« less
Dyja, R; Jankowski, A
2017-08-01
To assess the effect of two different additives (propylene glycol (PG) and polyethylene glycol 400 (PEG 400)) on release and in vitro skin retention of quercetin and chrysin from semisolid bases (amphiphilic creams and acidic carbomer gels). For obtaining semisolid formulations, flavonoids were pre-dissolved in the liquid (PG or PEG 400) or directly suspended in the semisolid base. Three chrysin formulations ('cream 0', 'PG-cream' and 'PEG 400-cream') and five quercetin formulations ('cream 0', 'PG cream', 'PEG 400 cream', 'gel 0' and 'PG gel') were prepared. The release studies were carried out in Franz diffusion cells by means of a cellulose membrane. The porcine ear skin was used in in vitro skin retention studies. The dissolution was a prerequisite to increase the release rates of tested flavonoids from obtained semisolid formulations. The cumulative amount of chrysin released after 6 h from 'PEG 400 cream' containing partly dissolved form of that flavonoid was higher than that from 'cream 0' or 'PG cream' containing its suspended form. The formulations containing quercetin dissolved in PG ('PG cream', 'PG gel') or PEG 400 ('PEG 400 cream') exhibited higher release rates of that flavonoid than corresponding semisolid suspensions ('cream 0' or 'gel 0'). The effects of both liquid additives (PG and PEG 400) on the cumulative amount of quercetin released after 6 h were comparable. However, there was no correlation between the release rate and the skin retention. The amounts of the flavonoids found in the skin were strongly affected by the type of the used solvent. While PG increased the skin retention of both flavonoids, PEG 400 had no effect on chrysin skin retention and delayed quercetin skin absorption. The proper choice of the solvent added to the semisolid base is crucial for enhanced skin delivery of the tested flavonoids. PG is more efficient absorption promoter than PEG 400 of both chrysin and quercetin. © 2017 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Global soil-climate-biome diagram: linking soil properties to climate and biota
NASA Astrophysics Data System (ADS)
Zhao, X.; Yang, Y.; Fang, J.
2017-12-01
As a critical component of the Earth system, soils interact strongly with both climate and biota and provide fundamental ecosystem services that maintain food, climate, and human security. Despite significant progress in digital soil mapping techniques and the rapidly growing quantity of observed soil information, quantitative linkages between soil properties, climate and biota at the global scale remain unclear. By compiling a large global soil database, we mapped seven major soil properties (bulk density [BD]; sand, silt and clay fractions; soil pH; soil organic carbon [SOC] density [SOCD]; and soil total nitrogen [STN] density [STND]) based on machine learning algorithms (regional random forest [RF] model) and quantitatively assessed the linkage between soil properties, climate and biota at the global scale. Our results demonstrated a global soil-climate-biome diagram, which improves our understanding of the strong correspondence between soils, climate and biomes. Soil pH decreased with greater mean annual precipitation (MAP) and lower mean annual temperature (MAT), and the critical MAP for the transition from alkaline to acidic soil pH decreased with decreasing MAT. Specifically, the critical MAP ranged from 400-500 mm when the MAT exceeded 10 °C but could decrease to 50-100 mm when the MAT was approximately 0 °C. SOCD and STND were tightly linked; both increased in accordance with lower MAT and higher MAP across terrestrial biomes. Global stocks of SOC and STN were estimated to be 788 ± 39.4 Pg (1015 g, or billion tons) and 63 ± 3.3 Pg in the upper 30-cm soil layer, respectively, but these values increased to 1654 ± 94.5 Pg and 133 ± 7.8 Pg in the upper 100-cm soil layer, respectively. These results reveal quantitative linkages between soil properties, climate and biota at the global scale, suggesting co-evolution of the soil, climate and biota under conditions of global environmental change.
Spectroscopic observations of the detached binary PG 1413 + 015
NASA Technical Reports Server (NTRS)
Fulbright, Michael S.; Liebert, James; Bergeron, P.; Green, Richard
1993-01-01
We present improved estimates of the stellar parameters of the eclipsing, precataclysmic binary system PG 1413 + 015 (GH Vir), which has an orbital period of only 8h16m. Model atmosphere fits a Balmer line profiles yield T(eff) = 48,800 +/- 1200 K and log g = 7.70 +/- 0.11 for the DAO white dwarf primary star, from which a mass of 0.51 +/- 0.04 solar mass is inferred using evolutionary models. An ultraviolet spectrum obtained with the IUE Observatory has a slope consistent with this temperature and the assumption of no interstellar extinction. A red CCD spectrum of the secondary star during the 12-minute total eclipse indicates a spectral type of M3 V-M5 V. Reanalysis of the eclipse light curve leads to an inferred radius of 0.15 solar radius and a mass of 0.10 solar mass for the secondary, the latter being marginally consistent with the spectral type. Reprocessing on the facing side of the secondary produces phase-dependent Balmer line emission and detectable variations in the continuum from 6500-9000 A. The observed levels of reprocessing are consistent with expectations based on the above stellar parameters.
John, William S.; Newman, Amy Hauck; Nader, Michael A.
2015-01-01
The dopamine D3 receptor (D3R) has been shown to mediate many of the behavioral effects of psychostimulants associated with high abuse potential. This study extended the assessment of the highly selective D3R antagonist PG01037 on cocaine and methamphetamine (MA) self-administration to include a food-drug choice procedure. Eight male rhesus monkeys (n=4/group) served as subjects in which complete cocaine and MA dose-response curves were determined daily in each session. When choice was stable, monkeys received acute and five-day treatment of PG01037 (1.0–5.6 mg/kg, i.v.). Acute administration of PG01037 was effective in reallocating choice from cocaine to food and decreasing cocaine intake, however, tolerance developed by day 5 of treatment. Up to doses that disrupted responding, MA choice and intake were not affected by PG01037 treatment. PG01037 decreased total reinforcers earned per session and the behavioral potency was significantly greater on MA-food choice compared to cocaine-food choice. Furthermore, the acute efficacy of PG01037 was correlated with the sensitivity of the D3/D2R agonist quinpirole to elicit yawning. These data suggest (1) that efficacy of D3R compounds in decreasing drug choice is greater in subjects with lower D3R, perhaps suggesting that it is percent occupancy that is the critical variable in determining efficacy and (2) differences in D3R activity in chronic cocaine vs. MA users. Although tolerance developed to the effects of PG01037 treatment on cocaine choice, tolerance did not develop to the disruptive effects on food-maintained responding. These findings suggest that combination treatments that decrease cocaine-induced elevations in DA may enhance the efficacy of D3R antagonists on cocaine self-administration. PMID:25576373
Project DAFNE - Drilling Active Faults in Northern Europe
NASA Astrophysics Data System (ADS)
Kukkonen, I. T.; Ask, M. S. V.; Olesen, O.
2012-04-01
We are currently developing a new ICDP project 'Drillling Active Faults in Northern Europe' (DAFNE) which aims at investigating, via scientific drilling, the tectonic and structural characteristics of postglacial (PG) faults in northern Fennoscandia, including their hydrogeology and associated deep biosphere [1, 2]. During the last stages of the Weichselian glaciation (ca. 9,000 - 15,000 years B.P.), reduced ice load and glacially affected stress field resulted in active faulting in Fennoscandia with fault scarps up to 160 km long and 30 m high. These postglacial (PG) faults are usually SE dipping, SW-NE oriented thrusts, and represent reactivated, pre-existing crustal discontinuities. Postglacial faulting indicates that the glacio-isostatic compensation is not only a gradual viscoelastic phenomenon, but includes also unexpected violent earthquakes, suggestively larger than other known earthquakes in stable continental regions. The research is anticipated to advance science in neotectonics, hydrogeology and deep biosphere studies, and provide important information for nuclear waste and CO2 disposal, petroleum exploration on the Norwegian continental shelf and studies of mineral resources in PG fault areas. We expect that multidisciplinary research applying shallow and deep drilling of postglacial faults would provide significant scientific results through generating new data and models, namely: (1) Understanding PG fault genesis and controls of their locations; (2) Deep structure and depth extent of PG faults; (3) Textural, mineralogical and physical alteration of rocks in the PG faults; (4) State of stress and estimates of paleostress of PG faults; (5) Hydrogeology, hydrochemistry and hydraulic properties of PG faults; (6) Dating of tectonic reactivation(s) and temporal evolution of tectonic systems hosting PG faults; (7) Existence/non-existence of deep biosphere in PG faults; (8) Data useful for planning radioactive waste disposal in crystalline bedrock; (9) Data on rock stress changes in the periphery of the inland ice; (10) Stress pattern along the Norwegian continental margin in relation to the bending spreading ridge and Plio-Pleistocene erosion, uplift and sedimentation with implications for fluid migration and sealing properties of petroleum reservoirs. (11) Data useful in predicting future seismic activity in areas of current deglaciation due to ongoing climatic warming.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, J. M.; Fung, J. W.; Mo, G.
2015-01-01
In order to improve quantification of the spatial distribution of carbon sinks and sources in the conterminous USA, we conduct a nested global atmospheric inversion with consideration of the spatial information of crop production and consumption. Spatially distributed 5 county-level cropland net primary productivity, harvested biomass, soil carbon change, and human and livestock consumption data over the conterminous USA are used for this purpose. Time-dependent Bayesian synthesis inversions are conducted based on CO₂ observations at 210 stations to infer CO₂ fluxes globally at monthly time steps with a nested focus on 30 regions in North America. Prior land surface carbonmore » 10 fluxes are first generated using a biospheric model, and the inversions are constrained using prior fluxes with and without adjustments for crop production and consumption over the 2002–2007 period. After these adjustments, the inverted regional carbon sink in the US Midwest increases from 0.25 ± 0.03 Pg C yr⁻¹ to 0.42 ± 0.13 Pg C yr⁻¹, whereas the large sink in the US Southeast forest region is weakened from 0.41±0.12 Pg C yr⁻¹ 15 to 0.29 ±0.12 Pg C yr⁻¹. These adjustments also reduce the inverted sink in the West region from 0.066 ± 0.04 Pg C yr⁻¹ to 0.040 ± 0.02 Pg C yr⁻1 because of high crop consumption and respiration by humans and livestock. The general pattern of sink increase in crop production areas and sink decreases (or source increases) in crop consumption areas highlights the importance of considering the lateral carbon transfer in crop 20 products in atmospheric inverse modeling, which provides an atmospheric perspective of the overall carbon balance of a region.« less
NASA Astrophysics Data System (ADS)
Liu, Hao; Lan, Peiqiang; Lu, Shangqing; Wu, Sufang
2018-06-01
Phosphogypsum (PG) as a low-cost calcium resource was used to prepare nano-CaCO3 in a three-phase system by reactions. Based on the population balance equation, nano-CaCO3 crystal nucleation and growth model in the gas (CO2)-liquid (NH3·H2O)-solid (CaSO4) three-phase system was established. The crystallization kinetic model of nano-CaCO3 in CO2-NH3·H2O-CaSO4 reactions system was experimental developed over an optimized temperature range of 20-40 °C and CO2 flow rate range of 138-251 ml/min as rCaCO3 =kn 32 πM2γ3/3R3ρ2T3 (C -C∗)0.8/[ ln (C /C∗) ]3 + πρ/3M kg3 kn(C -C∗) 2t3 , where nano-CaCO3 nucleation rate constant was kn = 6.24 ×1019 exp(-15940/RT) and nano-CaCO3 growth rate constant was kg = 0.79 exp(-47650/RT) respectively. Research indicated that nucleation rates and growth rates both increased with the increasing of temperature and CO32- ion concentration. And crystal growth was dependent on temperature more than that of nucleation process because the activation energy of CaCO3 growth was bigger than that of CaCO3 nucleation. Decreasing the reaction temperature and CO2 flow rate was more beneficial for producing nano-size CaCO3 because of the lower CaCO3 growth rates. The deduced kinetic equation could briefly predict the average particle sizes of nano-CaCO3.
Rahimzadeh, Mahsa; Poodat, Manijeh; Javadpour, Sedigheh; Qeshmi, Fatemeh Izadpanah; Shamsipour, Fereshteh
2016-01-01
Background: L-asparaginase has been used as a chemotherapeutic agent in treatment of lymphoblastic leukemia. In the present investigation, Bacillus sp. PG03 and Bacillus sp. PG04 were studied. Methods: L- asparaginases were produced using different culture media and were purified using ion exchange chromatography. Results: Maximum productivity was obtained when asparagine was used as the nitrogen source at pH 7 and 48 h after cultivation. New intracellular L-asparaginases showed an apparent molecular weight of 25 kDa and 30 kDa by SDS-PAGE respectively. These enzymes were active in a wide pH range (3-9) with maximum activity at pH 6 for Bacillus PG03 and pH 7 for Bacillus PG04 L-asparaginase. Bacillus PG03 enzyme was optimally active at 37 ˚C and Bacillus PG04 maximum activity was observed at 40˚C. Kinetic parameters km and Vmax of both enzymes were studied using L-asparagine as the substrate. Thermal inactivation studies of Bacillus PG03 and Bacillus PG04 L-asparaginase exhibited t1/2 of 69.3 min and 34.6 min in 37 ˚C respectively. Also T50 and ∆G of inactivation were measured for both enzymes. Conclusion: The results revealed that both enzymes had appropriate characteristics and thus could be a potential candidate for medical applications. PMID:27999622
Madry, Milena M; Spycher, Barbara S; Kupper, Jacqueline; Fuerst, Anton; Baumgartner, Markus R; Kraemer, Thomas; Naegeli, Hanspeter
2016-06-01
Compared to blood or urine, drugs can be detected for much longer periods in the long hair of horses. The aim of this study was to establish and validate a highly sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the detection and quantification of frequently prescribed opioids, sedatives and non-steroidal anti-inflammatory agents in the mane and tail hair of horses. Based on an average growth rate of about 2 cm per month, times of administration reported by horse owners or veterinary physicians were related to drug localizations in hair. Hair samples were collected from ten horses that received drug treatments and analyzed in segments of 2, 4 or 6 cm in length. Hair segments were decontaminated, cut into fragments and methanol-extracted under sonication. The extracts were analyzed by LC-MS/MS for 13 commonly used drugs using the validated procedure. Deuterated analogs were included as internal standards. Analytes were detected in hair samples with a length of up to 70 cm. Fourteen out of 16 hair samples were positive for at least one of the tested drugs. Segmentation allowed for time-resolved monitoring of periods of 1 to 3 months of drug administration. Concentrations in dark hair reached a maximum of 4.0 pg/mg for butorphanol, 6.0 pg/mg for tramadol, 1.4 pg/mg for morphine, 1.8 pg/mg for detomidine, 1.2 pg/mg for acepromazine, 39 pg/mg for flunixin, 5.0 pg/mg for firocoxib, and 3'600 pg/mg for phenylbutazone. Only trace amounts of meloxicam were detected. Drug detection correlated well with the reported period of medical treatment. No analytes were detected in the light-colored mane and tail hair samples from one horse despite preceding administrations of acepromazine and phenylbutazone. This study describes a sensitive and selective technique suitable for the validated detection and quantification of frequently prescribed veterinary drugs in horse hair. The segmental method can be applied for time-resolved long-term retrospective drug monitoring, for example in prepurchase examinations of horses as drug detection in hair can prove preceding medical treatments.
COX-2-derived endocannabinoid metabolites as novel inflammatory mediators.
Alhouayek, Mireille; Muccioli, Giulio G
2014-06-01
Cyclooxygenase-2 (COX-2) is an enzyme that plays a key role in inflammatory processes. Classically, this enzyme is upregulated in inflammatory situations and is responsible for the generation of prostaglandins (PGs) from arachidonic acid (AA). One lesser-known property of COX-2 is its ability to metabolize the endocannabinoids, N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG). Endocannabinoid metabolism by COX-2 is not merely a means to terminate their actions. On the contrary, it generates PG analogs, namely PG-glycerol esters (PG-G) for 2-AG and PG-ethanolamides (PG-EA or prostamides) for AEA. Although the formation of these COX-2-derived metabolites of the endocannabinoids has been known for a while, their biological effects remain to be fully elucidated. Recently, several studies have focused on the role of these PG-G or PG-EA in vivo. In this review we take a closer look at the literature concerning these novel bioactive lipids and their role in inflammation. Copyright © 2014 Elsevier Ltd. All rights reserved.
Serratos, Iris N; Pérez-Hernández, Gerardo; Garza-Ramos, Georgina; Hernández-Arana, Andrés; González-Mondragón, Edith; Zubillaga, Rafael A
2011-01-07
Electrostatic interactions have a central role in some biological processes, such as recognition of charged ligands by proteins. We characterized the binding energetics of yeast triosephosphate isomerase (TIM) with phosphorylated inhibitors 2-phosphoglycollate (2PG) and phosphoglycolohydroxamate (PGH). We determined the thermodynamic parameters of the binding process (K(b), ΔG(b), ΔH(b), ΔS(b) and ΔC(p)) with different concentrations of NaCl, using fluorimetric and calorimetric titrations in the conventional mode of ITC and a novel method, multithermal titration calorimetry (MTC), which enabled us to measure ΔC(p) in a single experiment. We ruled out specific interactions of Na(+) and Cl(-) with the native enzyme and did not detect significant linked protonation effects upon the binding of inhibitors. Increasing ionic strength (I) caused K(b), ΔG(b) and ΔH(b) to become less favorable, while ΔS(b) became less unfavorable. From the variation of K(b) with I, we determined the electrostatic contribution of TIM-2PG and TIM-PGH to ΔG(b) at I=0.06 M and 25 °C to be 36% and 26%, respectively. The greater affinity of PGH for TIM is due to a more favorable ΔH(b) compared to 2PG (by 19-24 kJ mol(-1) at 25 °C). This difference is compatible with PGH establishing up to five more hydrogen bonds with TIM. Both binding ΔC(p)s were negative, and less negative with increasing ionic strength. ΔC(p)s at I=0.06 M were much more negative than predicted by surface area models. Water molecules trapped in the interface when ligands bind to protein could explain the highly negative ΔCps. Thermodynamic binding functions for TIM-2PG changed more with ionic strength than those for TIM-PGH. This greater dependence is consistent with linked, but compensated, protonation equilibriums yielding the dianionic species of 2PG that binds to TIM, process that is not required for PGH. Copyright © 2010 Elsevier Ltd. All rights reserved.
Accelerated prompt gamma estimation for clinical proton therapy simulations.
Huisman, Brent F B; Létang, J M; Testa, É; Sarrut, D
2016-11-07
There is interest in the particle therapy community in using prompt gammas (PGs), a natural byproduct of particle treatment, for range verification and eventually dose control. However, PG production is a rare process and therefore estimation of PGs exiting a patient during a proton treatment plan executed by a Monte Carlo (MC) simulation converges slowly. Recently, different approaches to accelerating the estimation of PG yield have been presented. Sterpin et al (2015 Phys. Med. Biol. 60 4915-46) described a fast analytic method, which is still sensitive to heterogeneities. El Kanawati et al (2015 Phys. Med. Biol. 60 8067-86) described a variance reduction method (pgTLE) that accelerates the PG estimation by precomputing PG production probabilities as a function of energy and target materials, but has as a drawback that the proposed method is limited to analytical phantoms. We present a two-stage variance reduction method, named voxelized pgTLE (vpgTLE), that extends pgTLE to voxelized volumes. As a preliminary step, PG production probabilities are precomputed once and stored in a database. In stage 1, we simulate the interactions between the treatment plan and the patient CT with low statistic MC to obtain the spatial and spectral distribution of the PGs. As primary particles are propagated throughout the patient CT, the PG yields are computed in each voxel from the initial database, as a function of the current energy of the primary, the material in the voxel and the step length. The result is a voxelized image of PG yield, normalized to a single primary. The second stage uses this intermediate PG image as a source to generate and propagate the number of PGs throughout the rest of the scene geometry, e.g. into a detection device, corresponding to the number of primaries desired. We achieved a gain of around 10 3 for both a geometrical heterogeneous phantom and a complete patient CT treatment plan with respect to analog MC, at a convergence level of 2% relative uncertainty in the 90% yield region. The method agrees with reference analog MC simulations to within 10 -4 , with negligible bias. Gains per voxel range from 10 2 to 10 4 . The presented generic PG yield estimator is drop-in usable with any geometry and beam configuration. We showed a gain of three orders of magnitude compared to analog MC. With a large number of voxels and materials, memory consumption may be a concern and we discuss the consequences and possible tradeoffs. The method is available as part of Gate 7.2.
Robarge, Jason D; Desta, Zereunesay; Nguyen, Anne T; Li, Lang; Hertz, Daniel; Rae, James M; Hayes, Daniel F; Storniolo, Anna M; Stearns, Vered; Flockhart, David A; Skaar, Todd C; Henry, N Lynn
2017-02-01
Inter-individual differences in estrogen concentrations during treatment with aromatase inhibitors (AIs) may contribute to therapeutic response and toxicity. The aim of this study was to determine plasma concentrations of estradiol (E2), estrone (E1), and estrone sulfate (E1S) in a large cohort of AI-treated breast cancer patients. In a randomized, multicenter trial of postmenopausal women with early-stage breast cancer starting treatment with letrozole (n = 241) or exemestane (n = 228), plasma estrogen concentrations at baseline and after 3 months were quantitated using a sensitive mass spectrometry-based assay. Concentrations and suppression below the lower limit of quantification (LLOQ) were compared between estrogens and between drugs. The ranges of baseline estrogen concentrations were
Blood (1→3)-β-D-Glucan as a Diagnostic Test for HIV-Related Pneumocystis jirovecii Pneumonia
Komarow, Lauren; Finkelman, Malcolm A.; Grant, Philip M.; Andersen, Janet; Scully, Eileen; Powderly, William G.; Zolopa, Andrew R.
2011-01-01
(See the editorial commentary by Morris and Masur, on pages 203–204.) Background. Improved noninvasive diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) are needed. We evaluated the test characteristics of plasma (1→3)-β-D-glucan (β-glucan) for HIV-related PCP among a large group of patients presenting with diverse opportunistic infections (OIs). Methods. The study population included all 282 participants in AIDS Clinical Trials Group A5164, a study of early versus deferred antiretroviral therapy in conjunction with initial therapy of acute OIs. Baseline plasma samples were assayed for β-glucan, with standard assay reference values defining ≥80 pg/mL as positive. Before this analysis, diagnosis of PCP was independently adjudicated by 2 study investigators after reviewing reports from study sites. Results. A total of 252 persons had a β-glucan result that could be analyzed, 173 (69%) of whom had received a diagnosis of PCP. Median β-glucan with PCP was 408 pg/mL (interquartile range [IQR], 209–500 pg/mL), compared with 37 pg/mL (IQR, 31–235 pg/mL) without PCP (P < .001). The sensitivity of β-glucan dichotomized at 80 pg/mL for the diagnosis of PCP was 92% (95% confidence interval [CI], 87%–96%), and the specificity was 65% (95% CI, 53%–75%); positive and negative predictive values were 85% (95% CI, 79%–90%) and 80% (95% CI, 68%–89%) respectively, based on the study prevalence of 69% of patients with PCP. Rates of abnormal lactate dehyrogenase levels did not differ significantly between those with and without PCP. Conclusions. Blood (1→3)-β-D-glucan is strongly correlated with HIV-related PCP. In some clinical centers, this may be a more sensitive test than the induced sputum examination and could reduce the need for both bronchoscopy and empirical therapy of PCP. PMID:21690628
Huang, Zhouqing; Chen, Chen; Li, Sheng; Kong, Fanqi; Shan, Peiren; Huang, Weijian
2016-01-01
To assess the effect of amlodipine and atorvastatin on intercellular adhesion molecule (ICAM)-1 and tumor necrosis factor (TNF)-α expression, as endothelial function and inflammation indicators, respectively, in hypertensive patients with and without prediabetes. Forty-five consecutive patients with hypertension, diagnosed according to JNC7, were divided into two groups based on the presence (HD group, n = 23) or absence (H group, n = 22) of prediabetes, diagnosed according to 2010 ADA criteria, including impaired glucose tolerance (IGT) and fasting glucose tests. All patients simultaneously underwent 12-week treatment with daily single-pill amlodipine besylate/atorvastatin calcium combination (5/10 mg; Hisun-Pfizer Pharmaceuticals Co. Ltd). Serum isolated before and after treatment from overnight fasting blood samples was analyzed by ELISA. In the HD and H groups after vs. before 12-week amlodipine/atorvastatin treatment, there were significantly (all P < 0.01) lower levels of ICAM-1 (3.06 ± 0.34 vs. 4.07 ± 0.70 pg/ml; 3.26 ± 0.32 vs. 3.81 ± 0.60 pg/ml, respectively) and TNF-α (78.71 ± 9.19 vs. 110.94 ± 10.71 pg/ml; 80.95 ± 9.33 vs. 101.79 ± 11.72 pg/ml, respectively), with more pronounced reductions in HD vs. H group (ICAM-1Δ: 1.01 ± 0.80 vs. 0.55 ± 0.64 pg/ml, respectively, P = 0.037; TNF-αΔ: 32.23 ± 14.33 vs. 20.84 ± 14.89 pg/ml, respectively, P = 0.011), independent of the blood pressure (BP) and cholesterol level reduction. Amlodipine/atorvastatin improved endothelial function and inflammation, as reflected by lower circulating levels of ICAM-1 and TNF-α, more prominently in hypertensives with than without prediabetes. Starting statin treatment before overt diabetes in hypertensives might thus improve cardiovascular outcomes.
NASA Astrophysics Data System (ADS)
van der Werf, G. R.; Randerson, J. T.; Giglio, L.; Collatz, G. J.; Mu, M.; Kasibhatla, P. S.; Morton, D. C.; Defries, R. S.; Jin, Y.; van Leeuwen, T. T.
2010-12-01
New burned area datasets and top-down constraints from atmospheric concentration measurements of pyrogenic gases have decreased the large uncertainty in fire emissions estimates. However, significant gaps remain in our understanding of the contribution of deforestation, savanna, forest, agricultural waste, and peat fires to total global fire emissions. Here we used a revised version of the Carnegie-Ames-Stanford-Approach (CASA) biogeochemical model and improved satellite-derived estimates of area burned, fire activity, and plant productivity to calculate fire emissions for the 1997-2009 period on a 0.5° spatial resolution with a monthly time step. For November 2000 onwards, estimates were based on burned area, active fire detections, and plant productivity from the MODerate resolution Imaging Spectroradiometer (MODIS) sensor. For the partitioning we focused on the MODIS era. We used maps of burned area derived from the Tropical Rainfall Measuring Mission (TRMM) Visible and Infrared Scanner (VIRS) and Along-Track Scanning Radiometer (ATSR) active fire data prior to MODIS (1997-2000) and estimates of plant productivity derived from Advanced Very High Resolution Radiometer (AVHRR) observations during the same period. Average global fire carbon emissions according to this version 3 of the Global Fire Emissions Database (GFED3) were 2.0 Pg C year-1 with significant interannual variability during 1997-2001 (2.8 Pg C year-1 in 1998 and 1.6 Pg C year-1 in 2001). Globally, emissions during 2002-2007 were relatively constant (around 2.1 Pg C year-1) before declining in 2008 (1.7 Pg C year-1) and 2009 (1.5 Pg C year-1) partly due to lower deforestation fire emissions in South America and tropical Asia. On a regional basis, emissions were highly variable during 2002-2007 (e.g., boreal Asia, South America, and Indonesia), but these regional differences canceled out at a global level. During the MODIS era (2001-2009), most carbon emissions were from fires in grasslands and savannas (44%) with smaller contributions from tropical deforestation and degradation fires (20%), woodland fires (mostly confined to the tropics, 16%), forest fires (mostly in the extratropics, 15%), agricultural waste burning (3%), and tropical peat fires (3%). The contribution from agricultural waste fires was likely a lower bound because our approach for measuring burned area could not detect all of these relatively small fires. Total carbon emissions were on average 13% lower than in our previous (GFED2) work. For reduced trace gases such as CO and CH4, deforestation, degradation, and peat fires were more important contributors because of higher emissions of reduced trace gases per unit carbon combusted compared to savanna fires. Carbon emissions from tropical deforestation, degradation, and peatland fires were on average 0.5 Pg C year-1. The carbon emissions from these fires may not be balanced by regrowth following fire. Our results provide the first global assessment of the contribution of different sources to total global fire emissions for the past decade, and supply the community with an improved 13-year fire emissions time series.
Pituitary gigantism: a retrospective case series.
Creo, Ana L; Lteif, Aida N
2016-05-01
Pituitary gigantism (PG) is a rare pediatric disease with poorly defined long-term outcomes. Our aim is to describe the longitudinal clinical course in PG patients using a single-center, retrospective cohort study. Patients younger than 19 years diagnosed with PG were identified. Thirteen cases were confirmed based on histopathology of a GH secreting adenoma or hyperplasia and a height >2 SD for age and gender. Laboratory studies, initial pathology, and imaging were abstracted. Average age at diagnosis was 13 years with an average initial tumor size of 7.4×3.8 mm. Initial transsphenoidal surgery was curative in 3/12 patients. Four of the nine patients who failed the initial surgery required a repeat procedure. Octreotide successfully normalized GH levels in 1/6 patients with disease refractory to surgery (1/6). Two out of five patients received pegvisomant after failing octreotide but only one patient responded to treatment. Five patients were ultimately treated with radiosurgery or radiation patients were followed for an average of 10 years. PG is difficult to treat. In most patients, the initial transsphenoidal surgery failed to normalize GH levels. If the initial surgery was unsuccessful, repeat surgery was unlikely to control GH secretion. Treatment with octreotide or pegvisomant was successful in less than half the patients failing surgery. Radiosurgery was curative, but is not an optimal treatment for pediatric patients. Despite the small sample, our study suggests that the treatment outcome of pediatric PG may be different than adults.
Breath condenser coatings affect measurement of biomarkers in exhaled breath condensate.
Rosias, P P; Robroeks, C M; Niemarkt, H J; Kester, A D; Vernooy, J H; Suykerbuyk, J; Teunissen, J; Heynens, J; Hendriks, H J; Jöbsis, Q; Dompeling, E
2006-11-01
Exhaled breath condensate collection is not yet standardised and biomarker measurements are often close to lower detection limits. In the current study, it was hypothesised that adhesive properties of different condenser coatings interfere with measurements of eicosanoids and proteins in breath condensate. In vitro, condensate was derived from a collection model using two test solutions (8-isoprostane and albumin) and five condenser coatings (silicone, glass, aluminium, polypropylene and Teflon). In vivo, condensate was collected using these five coatings and the EcoScreen condenser to measure 8-isoprostane, and three coatings (silicone, glass, EcoScreen) to measure albumin. In vitro, silicone and glass coatings had significantly higher albumin recovery compared with the other coatings. A similar trend was observed for 8-isoprostane recovery. In vivo, median (interquartile range) 8-isoprostane concentrations were significantly higher using silicone (9.2 (18.8) pg.mL(-1)) or glass (3.0 (4.5) pg.mL(-1)) coating, compared with aluminium (0.5 (2.4) pg.mL(-1)), polypropylene (0.5 (0.5) pg.mL(-1)), Teflon (0.5 (0.0) pg.mL(-1)), and EcoScreen (0.5 (2.0) pg.mL(-1)). Albumin in vivo was mainly detectable using glass coating. In conclusion, a condenser with silicone or glass coating is more efficient for measurement of 8-isoprostane or albumin in exhaled breath condensate, than EcoScreen, aluminium, polypropylene or Teflon. Guidelines for exhaled breath condensate standardisation should include the most valid condenser coating to measure a specific biomarker.
Shi, Meng-Ting; Yang, Xin-An; Qin, Li-Ming; Zhang, Wang-Bing
2018-09-26
A gold particle deposited glassy carbon electrode (Au/GCE) was first used in electrochemical vapor generation (ECVG) technology and demonstrated to have excellent catalytic property for the electrochemical conversion process of aqueous mercury, especially for methylmercury (CH 3 Hg + ), to gaseous mercury. Systematical research has shown that the highly consistent or distinct difference between the atomic fluorescence spectroscopy signals of CH 3 Hg + and Hg 2+ can be achieved by controlling the electrolytic parameters of ECVG. Hereby, a new green and accurate method for mercury speciation analysis based on the distinguishing electrochemical reaction behavior of Hg 2+ and CH 3 Hg + on the modified electrode was firstly established. Furthermore, electrochemical impedance spectra and the square wave voltammetry displayed that the ECVG reaction of CH 3 Hg + may belong to the electrocatalytic mechanism. Under the selected conditions, the limits of detection of Hg 2+ and CH 3 Hg + are 5.3 ng L -1 and 4.4 ng L -1 for liquid samples and 0.53 pg mg -1 and 0.44 pg mg -1 for solid samples, respectively. The precision of the 5 measurements is less than 6% within the concentration of Hg 2+ and CH 3 Hg + ranging from 0.2 to 15.0 μg L -1 . The accuracy and practicability of the proposed method was verified by analyzing the mercury content in the certified reference material and several fish as well as water samples. Copyright © 2018 Elsevier B.V. All rights reserved.
Luo, Zhi-Bin
2013-01-01
To investigate N metabolism of two contrasting Populus species in acclimation to low N availability, saplings of slow-growing species (Populus popularis, Pp) and a fast-growing species (Populus alba × Populus glandulosa, Pg) were exposed to 10, 100, or 1000 μM NH4NO3. Despite greater root biomass and fine root surface area in Pp, lower net influxes of NH4 + and NO3 – at the root surface were detected in Pp compared to those in Pg, corresponding well to lower NH4 + and NO3 – content and total N concentration in Pp roots. Meanwhile, higher stable N isotope composition (δ15N) in roots and stronger responsiveness of transcriptional regulation of 18 genes involved in N metabolism were found in roots and leaves of Pp compared to those of Pg. These results indicate that the N metabolism of Pp is more sensitive to decreasing N availability than that of Pg. In both species, low N treatments decreased net influxes of NH4 + and NO3 –, root NH4 + and foliar NO3 – content, root NR activities, total N concentration in roots and leaves, and transcript levels of most ammonium (AMTs) and nitrate (NRTs) transporter genes in leaves and genes involved in N assimilation in roots and leaves. Low N availability increased fine root surface area, foliar starch concentration, δ15N in roots and leaves, and transcript abundance of several AMTs (e.g. AMT1;2) and NRTs (e.g. NRT1;2 and NRT2;4B) in roots of both species. These data indicate that poplar species slow down processes of N acquisition and assimilation in acclimation to limiting N supply. PMID:23963674
de Pinho, N B; Martucci, R B; Rodrigues, V D; D'Almeida, C A; Thuler, L C S; Saunders, C; Jager-Wittenaar, H; Peres, W A F
2018-05-19
Malnutrition in cancer is an independent factor associated with negative clinical outcomes. The aim was to evaluate the prevalence and independent risk factors for malnutrition in hospitalized cancer patients using the Patient-Generated Subjective Global Assessment (PG-SGA). We evaluated 4783 cancer patients, aged ≥20 years, in a hospital-based, multicenter, cross-sectional study. Patients were classified as well-nourished (PG-SGA Stage A), moderate/suspected malnutrition (PG-SGA Stage B), or severely malnourished (PG-SGA Stage C), and provided a score to define required nutritional interventions. Multivariate analysis was composed of the odds ratio (OR) estimated by ordinal polytomous logistic regression. 45.3% were classified as Stage B and 11.8% as Stage C. Moreover, 45.3% of the patients presented a need for nutritional intervention. The variables that presented the highest ORs for Stage B or Stage C were: problems with swallowing (OR 2.8, 95% confidence interval (CI) 2.2-3.4, p < 0.001), loss of appetite (OR 1.9, 95% CI 1.6-2.3, p < 0.001), vomiting (OR 1.8, 95% CI 1.5-2.3, p < 0.001), presence of more than 3 nutrition impact symptoms (OR 8.3, 95% CI 5.8-12, p < 0.001), and cancer site: lung (OR 4.6, 95% CI 3.2-6.6, p < 0.001), upper digestive cancer (OR 3.7, 95% CI 2.7-5.2, p < 0.001), and head and neck cancer (OR 3.7, 95% CI 2.7-5.2, p < 0.001). The score for Worksheet 4 on the PG-SGA had a higher association with malnutrition (OR 7.3, 95% CI 6.6-8.2, p < 0.001). Malnutrition is highly prevalent in cancer patients in Brazil, and is associated with nutritional impact symptoms, cancer site and age ≥65 years. Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Cumulative carbon emissions budgets consistent with 1.5 °C global warming
NASA Astrophysics Data System (ADS)
Tokarska, Katarzyna B.; Gillett, Nathan P.
2018-04-01
The Paris Agreement1 commits ratifying parties to pursue efforts to limit the global temperature increase to 1.5 °C relative to pre-industrial levels. Carbon budgets2-5 consistent with remaining below 1.5 °C warming, reported in the IPCC Fifth Assessment Report (AR5)2,6,8, are directly based on Earth system model (Coupled Model Intercomparison Project Phase 5)7 responses, which, on average, warm more than observations in response to historical CO2 emissions and other forcings8,9. These models indicate a median remaining budget of 55 PgC (ref. 10, base period: year 1870) left to emit from January 2016, the equivalent to approximately five years of emissions at the 2015 rate11,12. Here we calculate warming and carbon budgets relative to the decade 2006-2015, which eliminates model-observation differences in the climate-carbon response over the historical period9, and increases the median remaining carbon budget to 208 PgC (33-66% range of 130-255 PgC) from January 2016 (with mean warming of 0.89 °C for 2006-2015 relative to 1861-188013-18). There is little sensitivity to the observational data set used to infer warming that has occurred, and no significant dependence on the choice of emissions scenario. Thus, although limiting median projected global warming to below 1.5 °C is undoubtedly challenging19-21, our results indicate it is not impossible, as might be inferred from the IPCC AR5 carbon budgets2,8.
Kanavouras, Konstantinos; Tzatzarakis, Manolis N; Mastorodemos, Vasileios; Plaitakis, Andreas; Tsatsakis, Aristidis M
2011-11-01
Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD+opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 μg/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. Copyright © 2011 Elsevier Inc. All rights reserved.
Coconut genome size determined by flow cytometry: Tall versus Dwarf types.
Freitas Neto, M; Pereira, T N S; Geronimo, I G C; Azevedo, A O N; Ramos, S R R; Pereira, M G
2016-02-11
Coconuts (Cocos nucifera L.) are tropical palm trees that are classified into Tall and Dwarf types based on height, and both types are diploid (2n = 2x = 32 chromosomes). The reproduction mode is autogamous for Dwarf types and allogamous for Tall types. One hypothesis for the origin of the Dwarf coconut suggests that it is a Tall variant that resulted from either mutation or inbreeding, and differences in genome size between the two types would support this hypothesis. In this study, we estimated the genome sizes of 14 coconut accessions (eight Tall and six Dwarf types) using flow cytometry. Nuclei were extracted from leaf discs and stained with propidium iodide, and Pisum sativum (2C = 9.07 pg DNA) was used as an internal standard. Histograms with good resolution and low coefficients of variation (2.5 to 3.2%) were obtained. The 2C DNA content ranged from 5.72 to 5.48 pg for Tall accessions and from 5.58 to 5.52 pg for Dwarf accessions. The mean genome sizes for Tall and Dwarf specimens were 5.59 and 5.55 pg, respectively. Among all accessions, Rennel Island Tall had the highest mean DNA content (5.72 pg), whereas West African Tall had the lowest (5.48 pg). The mean coconut genome size (2C = 5.57 pg, corresponding to 2723.73 Mbp/haploid set) was classified as small. Only small differences in genome size existed among the coconut accessions, suggesting that the Dwarf type did not evolve from the Tall type.
Kontro, Inkeri; Svedström, Kirsi; Duša, Filip; Ahvenainen, Patrik; Ruokonen, Suvi-Katriina; Witos, Joanna; Wiedmer, Susanne K
2016-12-01
The effects of ionic liquids on model phospholipid membranes were studied by small-angle X-ray scattering, dynamic light scattering (DLS) and zeta potential measurements. Multilamellar 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine liposomes and large unilamellar vesicles composed of l-α-phosphatidylcholine (eggPC) and l-α-phosphatidylglycerol (eggPG) (80:20mol%) or eggPC, eggPG, and cholesterol (60:20:20mol%) were used as biomimicking membrane models. The effects of the phosphonium-based ionic liquids: tributylmethylphosphonium acetate, trioctylmethylphosphonium acetate, tributyl(tetradecyl)-phosphonium acetate, and tributyl(tetradecyl)-phosphonium chloride, were compared to those of 1-ethyl-3-methyl-imidazolium acetate. With multilamellar vesicles, the ionic liquids that did not disrupt liposomes decreased the lamellar spacing as a function of concentration. The magnitude of the effect depended on concentration for all studied ionic liquids. Using large unilamellar vesicles, first a slight decrease in the vesicle size, then aggregation of vesicles was observed by DLS for increasing ionic liquid concentrations. At concentrations just below those that caused aggregation of liposomes, large unilamellar vesicles were coated by ionic liquid cations, evidenced by a change in their zeta potential. The ability of phosphonium-based ionic liquids to affect liposomes is related to the length of the hydrocarbon chains in the cation. Generally, the ability of ionic liquids to disrupt liposomes goes hand in hand with inducing disorder in the phospholipid membrane. However, trioctylmethylphosphonium acetate selectively extracted and induced a well-ordered lamellar structure in phospholipids from disrupted cholesterol-containing large unilamellar vesicles. This kind of effect was not seen with any other combination of ionic liquids and liposomes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Climate data induced uncertainty in model-based estimations of terrestrial primary productivity
NASA Astrophysics Data System (ADS)
Wu, Zhendong; Ahlström, Anders; Smith, Benjamin; Ardö, Jonas; Eklundh, Lars; Fensholt, Rasmus; Lehsten, Veiko
2017-06-01
Model-based estimations of historical fluxes and pools of the terrestrial biosphere differ substantially. These differences arise not only from differences between models but also from differences in the environmental and climatic data used as input to the models. Here we investigate the role of uncertainties in historical climate data by performing simulations of terrestrial gross primary productivity (GPP) using a process-based dynamic vegetation model (LPJ-GUESS) forced by six different climate datasets. We find that the climate induced uncertainty, defined as the range among historical simulations in GPP when forcing the model with the different climate datasets, can be as high as 11 Pg C yr-1 globally (9% of mean GPP). We also assessed a hypothetical maximum climate data induced uncertainty by combining climate variables from different datasets, which resulted in significantly larger uncertainties of 41 Pg C yr-1 globally or 32% of mean GPP. The uncertainty is partitioned into components associated to the three main climatic drivers, temperature, precipitation, and shortwave radiation. Additionally, we illustrate how the uncertainty due to a given climate driver depends both on the magnitude of the forcing data uncertainty (climate data range) and the apparent sensitivity of the modeled GPP to the driver (apparent model sensitivity). We find that LPJ-GUESS overestimates GPP compared to empirically based GPP data product in all land cover classes except for tropical forests. Tropical forests emerge as a disproportionate source of uncertainty in GPP estimation both in the simulations and empirical data products. The tropical forest uncertainty is most strongly associated with shortwave radiation and precipitation forcing, of which climate data range contributes higher to overall uncertainty than apparent model sensitivity to forcing. Globally, precipitation dominates the climate induced uncertainty over nearly half of the vegetated land area, which is mainly due to climate data range and less so due to the apparent model sensitivity. Overall, climate data ranges are found to contribute more to the climate induced uncertainty than apparent model sensitivity to forcing. Our study highlights the need to better constrain tropical climate, and demonstrates that uncertainty caused by climatic forcing data must be considered when comparing and evaluating carbon cycle model results and empirical datasets.
Cornelli, Umberto; Belcaro, Giovanni; Recchia, Martino; D'Orazio, Nicolantonio
2017-01-01
Abstract Background: Short-term treatment of overweight and obesity with polyglucosamine (PG) was found to be more effective than placebo and orlistat in double-blind clinical studies. Objective: The aim of the study was to compare the efficacy of long-term (12-mo) treatment of weight loss with PG and placebo (PL). Methods: This was a double-blind randomized study in 100 participants of both sexes with a body mass index (in kg/m2) >30 to <35. One group of 50 participants was treated for 1 y with PG at 1.6 g/d and a similar group received PL. PG is a combination of low-molecular-weight chitosan with organic acids. Participants were instructed to reduce their caloric intake by 10% and increase the physical activity level by 9 metabolic equivalent task hours/wk. Dietary compliance was checked every 3 mo by using a weekly questionnaire [food intake assessment (FIA)] based on 25 different food servings. Body weight (BW), waist circumference (WC), blood pressure (BP), glucose, lipids, and high-sensitivity C-reactive protein (hs-CRP) were also monitored. Results: Ninety-seven participants completed the study (49 in the PG group, 48 in the PL group). The decrease in calories was similar in both groups, as was the change in number of food servings (P > 0.05, ANOVA). Decreases in BW and WC were 8.0 kg and 10.2 cm, respectively, in the PL group, whereas they were 12.1 kg and 13.3 cm in the PG group (P < 0.001, ANOVA). The decrease in BP, plasma lipids, glucose, and hs-CRP was more evident in the group treated with PG (P < 0.05, ANOVA). The intake of lipids was found to correlate directly with hs-CRP, with the exception of extra-virgin olive oil. Conclusions: PG was found to be more effective than PL in reducing BW, WC, glucose, BP, plasma lipids, and hs-CRP in moderately obese individuals undergoing a 10% caloric reduction and a slight increase in physical activity. Dietary monitoring with the use of an FIA was an effective tool in supporting dietary compliance. This trial was registered at clinicaltrials.gov as U111111292405 (WHO).