Short- and Long-Term Outcomes of Student Field Research Experiences in Special Populations.
Soliman, Amr S; Chamberlain, Robert M
2016-06-01
Global health education and training of biomedical students in international and minority health research is expending through U.S. academic institutions. This study addresses the short- and long-term outcomes of an NCI-funded R25 short-term summer field research training program. This program is designed for MPH and Ph.D. students in cancer epidemiology and related disciplines, in international and minority settings (special populations) in a recent 7-year period. Positive short-term outcome of 73 students was measured as publishing a manuscript from the field research data and having a job in special populations. Positive long-term outcome was measured as having a post-doc position, being in a doctoral program, and/or employment in special populations at least 3 years from finishing the program. Significant factors associated with both short- and long-term success included resourcefulness of the student and compatibility of personalities and interests between the student and the on-campus and off-campus mentors. Short-term-success of students who conducted international filed research was associated with visits of the on-campus mentor to the field site. Short-term success was also associated with extent of mentorship in the field site and with long-term success. Future studies should investigate how field research sites could enhance careers of students, appropriateness of the sites for specific training competencies, and how to maximize the learning experience of students in international and minority research sites.
Rebecca E. Ibach; Craig M. Clemons; Rebecca L. Schumann
2007-01-01
Although laboratory evaluations of wood-plastic composites (WPCs) are helpful in predicting long-term durability, field studies are needed to verify overall long-term durability. Field exposure can encompass numerous degradations i.e., fungal, ultraviolet light, moisture, wind, temperature, freeze/thaw, wet/ dry cycling, termites, mold, etc. that traditionally are...
Putting Biology Students Out to Grass: the Nettlecombe Experiment After Thirteen Years.
ERIC Educational Resources Information Center
Crothers, J. H.; Lucas, A. M.
1982-01-01
The importance of examining both the natural history of organisms being investigated and numerical data from long-term field experiments is illustrated by describing a long-running field experiment at an English Field Study Council Centre. Sample results are discussed and alternative methods of using field studies in biology instruction are…
THE PHYTOAVAILABILITY OF CADMIUM TO LETTUCE IN LONG-TERM BIOSOLIDS-AMENDED SOILS
A field study was conducted to assess the phytoavailability of Cd in long-term biosolids-amended field plots managed at high and low pH. The experiment, established 13-15 yr prior to the present cropping, on a Christiana fine sandy loam soil (a clayey, kaolinitic, mesic Typic Pa...
Tracking Trends in Fractional Forest Cover Change using Long Term Data from AVHRR and MODIS
NASA Astrophysics Data System (ADS)
Kim, D. H.; DiMiceli, C.; Sohlberg, R. A.; Hansen, M.; Carroll, M.; Kelly, M.; Townshend, J. R.
2014-12-01
Tree cover affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Accurate and long-term continuous observation of tree cover change is critical for the study of the gradual ecosystem change. Tree cover is most commonly inferred from categorical maps which may inadequately represent within-class heterogeneity for many analyses. Alternatively, Vegetation Continuous Fields data measures fractions or proportions of pixel area. Recent development in remote sensing data processing and cross sensor calibration techniques enabled the continuous, long-term observations such as Land Long-Term Data Records. Such data products and their surface reflectance data have enhanced the possibilities for long term Vegetation Continuous Fields data, thus enabling the estimation of long term trend of fractional forest cover change. In this presentation, we will summarize the progress in algorithm development including automation of training selection for deciduous and evergreen forest, the preliminary results, and its future applications to relate trends in fractional forest cover change and environmental change.
Long Term Monitoring of Broken and Seated Pavements
DOT National Transportation Integrated Search
2002-05-01
This report presents details of a study conducted to evaluate the long term performance of asphalt overlays on broken and seated : (B/S) concrete p avements, us ing field expe riments. Th e primary p urpose o f this study is to evaluate the effective...
Birch, David G.; Bennett, Lea D.; Duncan, Jacque L.; Weleber, Richard G.; Pennesi, Mark E.
2016-01-01
Purpose To evaluate the long-term efficacy of ciliary neurotrophic factor delivered via an intraocular encapsulated cell implant for the treatment of retinitis pigmentosa (RP). Design Long-term follow up of a multicenter, sham-controlled study. Methods Thirty-six patients at three CNTF4 sites were randomly assigned to receive a high- or low- dose implant in one eye and sham surgery in the fellow eye. The primary endpoint (change in visual field sensitivity at 12 months) has been reported previously.1 Here we report long-term visual acuity, visual field and optical coherence tomography (OCT) outcomes in 24 patients either retaining or explanting the device at 24 months relative to sham-treated eyes. Results Eyes retaining the implant showed significantly greater visual field loss from baseline than either explanted eyes or sham eyes through 42 months. By 60 months and continuing through 96 months, visual field loss was comparable among sham-treated eyes, eyes retaining the implant and explanted eyes, as was visual acuity and OCT macular volume. Conclusions Over the short term, ciliary neurotrophic factor released continuously from an intra-vitreal implant lead to loss of total visual field sensitivity that was greater than the natural progression in the sham-treated eye. This additional loss of sensitivity related to the active implant was reversible when the implant was removed. Over the long term (60 – 96 months), there was no evidence of efficacy for visual acuity, visual field sensitivity or OCT measures of retinal structure. PMID:27457255
Performance oriented guidance for Mississippi chip seals - volume II.
DOT National Transportation Integrated Search
2013-12-01
A laboratory and field study was conducted related to long term chip seal performance. This reports primary : objective was to initiate development of a long term performance (LTP) test protocol for chip seals focused on : aggregate retention. Key...
Potential utility of future satellite magnetic field data
NASA Technical Reports Server (NTRS)
1984-01-01
The requirements for a program of geomagnetic field studies are examined which will satisfy a wide range of user needs in the interim period between now and the time at which data from the Geopotential Research Mission (GRM) becomes available, and the long term needs for NASA's program in this area are considered. An overview of the subject, a justification for the recommended activities in the near term and long term, and a summary of the recommendations reached by the contributors is included.
Long-Term Effects of Primary Schools on Mathematics Achievement of Students at Age 17
ERIC Educational Resources Information Center
Vanwynsberghe, Griet; Vanlaar, Gudrun; Van Damme, Jan; De Fraine, Bieke
2017-01-01
In the field of educational effectiveness research, school effects are generally studied in the short term (i.e. during the same phase of schooling). The aim of this study is to investigate long-term primary school effects on students' achievement in mathematics at the end of secondary education. We also investigate which primary school…
Pachón-García, F T; Paniagua-Sánchez, J M; Rufo-Pérez, M; Jiménez-Barco, A
2014-12-01
This article analyses the electric field levels around medium-wave transmitters, delimiting the temporal variability of the levels received at a pre-established reception point. One extensively used dosimetric criterion is to consider historical levels of the field recorded over a certain period of time so as to provide an overall perspective of radio-frequency electric field exposure in a particular environment. This aspect is the focus of the present study, in which the measurements will be synthesised in the form of exposure coefficients. Two measurement campaigns were conducted: one short term (10 days) and the other long term (1 y). The short-term data were used to study which probability density functions best approximate the measured levels. The long-term data were used to compute the principal statistics that characterise the field values over a year. The data that form the focus of the study are the peak traces, since these are the most representative from the standpoint of exposure. The deviations found were around 6 % for short periods and 12 % for long periods. The information from the two campaigns was used to develop and implement a computer application based on the Monte Carlo method to simulate values of the field, allowing one to carry out robust statistics. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Long-term impact of precision agriculture on a farmer’s field
USDA-ARS?s Scientific Manuscript database
Targeting management practices and inputs with precision agriculture has high potential to meet some of the grand challenges of sustainability in the coming century. Although potential is high, few studies have documented long-term effects of precision agriculture on crop production and environmenta...
Xu, L Y; Wang, M Y; Shi, X Z; Yu, Q B; Shi, Y J; Xu, S X; Sun, W X
2018-08-01
The shift from rice-wheat rotation (RWR) to greenhouse vegetable soils has been widely practiced in China. Several studies have discussed the changes in soil properties with land-use changes, but few studies have sought to address the differences in soil pore properties, especially for fields based on long-term organic fertilization under greenhouse vegetable system from RWR fields. This study uses the X-ray computed tomography (CT) scanning and statistical analysis to compare the long-term effects of the conversion of organic greenhouse vegetable fields (over one year, nine years, and fourteen years) from RWR fields on the soil macropore structure as well as the influencing factors from samples obtained in Nanjing, Jiangsu, China, using the surface soil layer and triplicate samples. The results demonstrated that the macropore structure became more complex and stable, with a higher connectivity, fractal dimension (FD) and a lower degree of anisotropy (DA), as the greenhouse vegetable planting time increased. The total topsoil macroporosity increased considerably, but the rate of increase gradually decelerated with time. The transmission pores (round pores ranging from 50 to 500μm) increased with time, but the biopores (>2000μm) clearly decreased after nine years of use as greenhouse vegetable fields. Soil organic matter (OM) has a significant relationship with the soil pore structure characteristics, especially for the transmission pores. In addition, organic fertilization on the topsoil had a short-term effect on the pores, but the effect stabilized and had a weak influence on the pores over longer periods. These results suggested that organic fertilization was conducive for controlling soil degradation regarding it physical quality for water and oxygen availability in the short term. Copyright © 2018 Elsevier B.V. All rights reserved.
Ionospheric Trend Over Wuhan During 1947-2017: Comparison Between Simulation and Observation
NASA Astrophysics Data System (ADS)
Yue, Xinan; Hu, Lianhuan; Wei, Yong; Wan, Weixing; Ning, Baiqi
2018-02-01
Since Roble and Dickinson (1989), who drew the community's attention about the greenhouse gas effect on the ionosphere, huge efforts have been implemented on ionospheric climate study. However, direct comparison between observations and simulations is still rare. Recently, the Wuhan ionosonde observations were digitized and standardized through unified method back to 1947. In this study, the NCAR-TIEGCM was driven by Mauna Loa Observatory observed CO2 level and International Geomagnetic Reference Field (IGRF) geomagnetic field to simulate their effects on ionospheric long-term trend over Wuhan. Only March equinox was considered in both data analysis and simulation. Simulation results show that the CO2 and geomagnetic field have comparable effect on hmF2 trend, while geomagnetic field effect is stronger than CO2 on foF2 trend over Wuhan. Both factors result in obvious but different diurnal variations of foF2/hmF2 long-term trends. The geomagnetic field effect is nonlinear versus years since the long-term variation of geomagnetic field intensity and orientation is complex. Mean value of foF2 and hmF2 trend is (-0.0021 MHz/yr, -0.106 km/yr) and (-0.0022 MHz/yr, -0.0763 km/yr) for observation and simulation, respectively. Regarding the diurnal variation of the trend, the simulation accords well with that of observation except hmF2 results around 12 UT. Overall, good agreement between observation and simulation illustrates the good quality of Wuhan ionosonde long-term data and the validity of ancient ionosphere reconstruction based on realistic indices driving simulation.
NASA Astrophysics Data System (ADS)
Weiser, D. A.; Jackson, D. D.
2015-12-01
In a tectonically active area, a definitive discrimination between geothermally-induced and tectonic earthquakes is difficult to achieve. We focus our study on California's 11 major geothermal fields: Amedee, Brawley, Casa Diablo, Coso, East Mesa, The Geysers, Heber, Litchfield, Salton Sea, Susanville, and Wendel. The Geysers geothermal field is the world's largest geothermal energy producer. California's Department of Oil Gas and Geothermal Resources provides field-wide monthly injection and production volumes for each of these sites, which allows us to study the relationship between geothermal pumping activities and seismicity. Since many of the geothermal fields began injecting and producing before nearby seismic stations were installed, we use smoothed seismicity since 1932 from the ANSS catalog as a proxy for tectonic earthquake rate. We examine both geothermal pumping and long-term earthquake rate as factors that may control earthquake rate. Rather than focusing only on the largest earthquake, which is essentially a random occurrence in time, we examine how M≥4 earthquake rate density (probability per unit area, time, and magnitude) varies for each field. We estimate relative contributions to the observed earthquake rate of M≥4 from both a long-term earthquake rate (Kagan and Jackson, 2010) and pumping activity. For each geothermal field, respective earthquake catalogs (NCEDC and SCSN) are complete above at least M3 during the test period (which we tailor to each site). We test the hypothesis that the observed earthquake rate at a geothermal site during the test period is a linear combination of the long-term seismicity and pumping rates. We use a grid search to determine the confidence interval of the weighting parameters.
NASA Astrophysics Data System (ADS)
Pick, L.; Korte, M. C.
2016-12-01
Magnetospheric currents generate the largest external contribution to the geomagnetic field observed on Earth. Of particular importance is the solar-driven effect of the ring current whose fluctuations overlap with internal field secular variation (SV). Recent core field models thus co-estimate this effect but their validity is limited to the last 15 years offering satellite data. We aim at eliminating magnetospheric modulation from the whole geomagnetic observatory record from 1840 onwards in order to obtain clean long-term SV that will enhance core flow and geodynamo studies.The ring current effect takes form of a southward directed external dipole field aligned with the geomagnetic main field axis. Commonly the Dst index (Sugiura, 1964) is used to parametrize temporal variations of this dipole term. Because of baseline instabilities, the alternative RC index was derived from hourly means of 21 stations spanning 1997-2013 (Olsen et al., 2014). We follow their methodology based on annual means from a reduced station set spanning 1960-2010. The absolute level of the variation so determined is "hidden" in the static lithospheric offsets taken as quiet-time means. We tackle this issue by subtracting crustal biases independently calculated for each observatory from an inversion of combined Swarm satellite and observatory data.Our index reproduces the original annual RC index variability with a reasonable offset of -10 nT in the reference time window 2000-2010. Prior to that it depicts a long-term trend consistent with the external dipole term from COV-OBS (Gillet et al., 2013), being the only long-term field model available for comparison. Sharper variations that are better correlated with the Ap index than the COV-OBS solution lend support to the usefulness of our initial modeling approach. Following a detailed sensitivity study of station choice future work will focus on increasing the resolution from annual to hourly means.
Apprenticeships, Collaboration and Scientific Discovery in Academic Field Studies
NASA Astrophysics Data System (ADS)
Madden, Derek Scott; Grayson, Diane J.; Madden, Erinn H.; Milewski, Antoni V.; Snyder, Cathy Ann
2012-11-01
Teachers may use apprenticeships and collaboration as instructional strategies that help students to make authentic scientific discoveries as they work as amateur researchers in academic field studies. This concept was examined with 643 students, ages 14-72, who became proficient at field research through cognitive apprenticeships with the Smithsonian Institute, School for Field Studies and Earthwatch. Control student teams worked from single research goals and sets of methods, while experimental teams varied goals, methods, and collaborative activities in Kenya, Costa Rica, Panama, and Ecuador. Results from studies indicate that students who conducted local pilot studies, collaborative symposia, and ongoing, long-term fieldwork generated significantly more data than did control groups. Research reports of the experimental groups were ranked highest by experts, and contributed the most data to international science journals. Data and anecdotal information in this report indicate that structured collaboration in local long-term studies using apprenticeships may increase the potential for students' academic field studies contribution of new information to science.
Fischer, David L
2005-11-01
Long-term risks of pesticides to birds and mammals are currently assessed by comparing effects thresholds determined in chronic laboratory studies to exposure levels expected to occur in the field. However, there is often a mismatch between exposure patterns tested in the laboratory tests (exposure levels held constant) and those experienced by animals in the field (exposure levels varying over time). Three methods for addressing this problem are presented and discussed. Time-weighted averaging (TWA) converts a variable field exposure regime to a single value that can be compared directly to the laboratory test results. Body-burden modeling (BBM) is applied to both laboratory and field exposure regimes allowing a straightforward comparison of body residue levels expected for each situation. Temporal analysis (TA) uses expert judgment to decide if the length of time exposure exceeds a toxicity threshold is long enough to cause biologically significant effects. To reduce uncertainty in long-term assessments, the conduct of specialized laboratory tests in which test subjects are administered a time-varying exposure that mimics what occurs in the field should be considered. Such tests may also be useful testing the validity of each of these assessment methods.
NASA Astrophysics Data System (ADS)
Ishchuk, V. M.; Kuzenko, D. V.
2016-08-01
The paper presents results of experimental study of the dielectric constant relaxation during aging process in Pb(Zr,Ti)O3 based solid solutions (PZT) after action of external DC electric field. The said process is a long-term one and is described by the logarithmic function of time. Reversible and nonreversible relaxation process takes place depending on the field intensity. The relaxation rate depends on the field strength also, and the said dependence has nonlinear and nonmonotonic form, if external field leads to domain disordering. The oxygen vacancies-based model for description of the long-term relaxation processes is suggested. The model takes into account the oxygen vacancies on the sample's surface ends, their conversion into F+- and F0-centers under external effects and subsequent relaxation of these centers into the simple oxygen vacancies after the action termination. F-centers formation leads to the violation of the original sample's electroneutrality, and generate intrinsic DC electric field into the sample. Relaxation of F-centers is accompanied by the reduction of the electric field, induced by them, and relaxation of the dielectric constant, as consequent effect.
Zhang, Hongling; Liang, Chenghua; Du, Liyu; Chen, Xinzhi; Li, Jibai
2006-05-01
The study showed that on a sheltered vegetable field, a long-term application of organic plus chemical fertilizers induced a higher content of loosely combined soil humus than applying chemical fertilizers alone, while there was no significant difference in firmly combined humus content among different fertilization treatments. More tightly combined humus was observed in organic fertilizer treatments than in chemical fertilizer treatments, and the highest content (11.53 g x kg(-1)) was in the treatment of organic fertilizer plus chemical NPK. The ratio of loosely/tightly combined humus tended to decrease after a long-term application of organic fertilizer, being the lowest (1.10) in the treatment of organic fertilizer plus chemical NPK.
Szemerszky, Renáta; Zelena, Dóra; Barna, István; Bárdos, György
2010-01-15
It is believed that different electromagnetic fields do have beneficial and harmful biological effects. The aim of the present work was to study the long-term consequences of 50 Hz electromagnetic field (ELF-EMF) exposure with special focus on the development of chronic stress and stress-induced psychopathology. Adult male Sprague-Dawley rats were exposed to ELF-EMF (50 Hz, 0.5 mT) for 5 days, 8h daily (short) or for 4-6 weeks, 24h daily (long). Anxiety was studied in elevated plus maze test, whereas depression-like behavior of the long-treated group was examined in the forced swim test. Some days after behavioral examination, the animals were decapitated among resting conditions and organ weights, blood hormone levels as well as proopiomelanocortin mRNA level from the anterior lobe of the pituitary gland were measured. Both treatments were ineffective on somatic parameters, namely none of the changes characteristic to chronic stress (body weight reduction, thymus involution and adrenal gland hypertrophy) were present. An enhanced blood glucose level was found after prolonged ELF-EMF exposure (p=0.013). The hormonal stress reaction was similar in control and short-term exposed rats, but significant proopiomelanocortin elevation (p<0.000) and depressive-like behavior (enhanced floating time; p=0.006) were found following long-term ELF-EMF exposure. Taken together, long and continuous exposure to relatively high intensity electromagnetic field may count as a mild stress situation and could be a factor in the development of depressive state or metabolic disturbances. Although we should stress that the average intensity of the human exposure is normally much smaller than in the present experiment.
USDA-ARS?s Scientific Manuscript database
Biosolids have been applied to agricultural land for many years as a source of plant nutrients. There are growing concerns of residual phosphorus and metals from long-term biosolids amended fields and their potential impact on the environment. Objectives of this study were to determine, i) phosphor...
Court-Kowalski, Stefan; Finnie, John W; Manavis, Jim; Blumbergs, Peter C; Helps, Stephen C; Vink, Robert
2015-04-01
This study was designed to determine whether long-term (2 years) brain exposure to mobile telephone radiofrequency (RF) fields produces any astrocytic activation as these glia react to a wide range of neural perturbations by astrogliosis. Using a purpose-designed exposure system at 900 MHz, mice were given a single, far-field whole body exposure at a specific absorption rate of 4 W/kg on five successive days per week for 104 weeks. Control mice were sham-exposed or freely mobile in a cage to control any stress caused by immobilization in the exposure module. Brains were perfusion-fixed with 4% paraformaldehyde and three coronal levels immunostained for glial fibrillary acidic protein (GFAP). These brain slices were then examined by light microscopy and the amount of this immunomarker quantified using a color deconvolution method. There was no change in astrocytic GFAP immunostaining in brains after long-term exposure to mobile telephony microwaves compared to control (sham-exposed or freely moving caged mice). It was concluded that long-term (2 years) exposure of murine brains to mobile telephone RF fields did not produce any astrocytic reaction (astrogliosis) detectable by GFAP immunostaining. © 2015 Wiley Periodicals, Inc.
Planning long-term vegetation studies at landscape scales
Stohlgren, Thomas J.
1995-01-01
Long-term ecological research is receiving more attention now than ever before. Two recent books, Long-term Studies in Ecology: Approaches and Alternatives, edited by Gene Likens (1989), and Long-term Ecological Research: An International Perspective, edited by Paul Risser (1991), prompt the question, “Why are these books so thin?” Except for data from paleoecological, retrospective studies (see below), there are exceptionally few long-term data sets in terrestrial ecology (Strayer et al. 1986; Tilman 1989; this volume). In a sample of 749 papers published in Ecology, Tilman (1989) found that only 1.7% of the studies lasted at least five field seasons. Only one chapter in each of the review books dealt specifically with expanding both the temporal and the spatial scales of ecological research (Berkowitz et al. 1989; Magnuson et al. 1991). Judging by the growing number of landscape-scale long-term studies, however, such as the Long-Term Ecological Research (LTER) Program (Callahan 1991), the U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP; Palmer et al. 1991), the U.S. Army’s Land Condition-Trend Analysis (LCTA) Program (Diersing et al. 1992), and various agencies’ global change research programs (CEES 1993), there is a growing interest to expand ecological research both temporally and spatially.
Long-Term Ecological Monitoring Field Sampling Plan for 2007
DOE Office of Scientific and Technical Information (OSTI.GOV)
T. Haney
2007-07-31
This field sampling plan describes the field investigations planned for the Long-Term Ecological Monitoring Project at the Idaho National Laboratory Site in 2007. This plan and the Quality Assurance Project Plan for Waste Area Groups 1, 2, 3, 4, 5, 6, 7, 10, and Removal Actions constitute the sampling and analysis plan supporting long-term ecological monitoring sampling in 2007. The data collected under this plan will become part of the long-term ecological monitoring data set that is being collected annually. The data will be used t determine the requirements for the subsequent long-term ecological monitoring. This plan guides the 2007more » investigations, including sampling, quality assurance, quality control, analytical procedures, and data management. As such, this plan will help to ensure that the resulting monitoring data will be scientifically valid, defensible, and of known and acceptable quality.« less
Madjid Ansari, Alireza; Farzampour, Shahrokh; Sadr, Ali; Shekarchi, Babak; Majidzadeh-A, Keivan
2016-02-01
Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2h and 2 weeks 2h a day). Locomotor behavior was assessed by using open-field test (OFT) followed by FST to evaluate the immobility time. Accordingly, NΩ-nitro-l-arginine methyl ester 30 mg/kg was used to exert anti-depressant like effect. According to the results, short term exposure did not alter the immobility time, whereas long term exposure significantly reduces immobility time (p<0.01). However, it was revealed that the locomotion did not differ among all experimental groups. Short term exposure reversed the anti-depressant like effect resulting from 30 mg/kg of NΩ-nitro-l-arginine methyl ester (p<0.01). It has been concluded that long term exposure could alter the depressive disorder in mice, whereas short term exposure has no significant effect. Also, reversing the anti-depressant activity of L-NAME indicates a probable increase in the brain nitric oxide. Copyright © 2016 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Cartwright, T. J.; Hallar, B.
2018-01-01
In this study, we present the long-term influence of an after school science practicum associated with an elementary science methods course. The practicum or field experience could be considered a community-based service learning programme as it is situated both within and for the community. Study participants included eight third- and fifth-grade…
NASA Astrophysics Data System (ADS)
Houben, Peter
2008-10-01
Agricultural landscapes with a millennial-scale history of cultivation are common in many loess areas of central Europe. Over time, patterns of erosion and sedimentation have been continually modified via the variable imposition of anthropogenic discontinuities and linkages on fragmented hillslope sediment cascades, which eventually caused the complicated soilscape pattern. These field records challenge topographically oriented models of hillslope erosion and simple predictions of longer-term change of spatial soilscape by cultivation activities. A thorough understanding how soilscape patterns form in the long-term, however, is essential to develop spatial concepts of the sediment budget, particularly for the spatial modeling of anthropogenic hillslope sediment flux using GIS. In this study I used extensive datasets of anthropogenic soil truncation and burial in a typical undulating loess watershed in southern Germany (10 km 2, Wetterau Basin, N of Frankfurt a.M.). Spatial soilscape properties and historic sediment flux, as caused by cultivation over seven millennia, were evaluated by these data. The soilscape pattern on the low-gradient hillslopes of the study area was found to be marked by a statistical near-random pattern of varying depth (thickness) of truncation and overthickened burial. Moreover, it was shown that truncation and burial had developed independently from each other and did not correlate with either hillslope gradient or downslope curvature. Hence, in the field any combination of (few) nearly preserved, severely truncated or completely removed soil profiles with either no, some or a thick sediment cover is present, thereby lacking an obvious spatial pattern. Here, I suggest putting long-term change of the soilscape into a contextual anthropogeomorphic systems perspective, that accommodates components of human-induced soil erosion operating at different spatial scales to interpret the longer-term spatial consequences at the hillslope-system level. In the study area, system scale linkages are marked by the spatial intersection of a finer-scaled managed field system with a broader hillslope-scale framework of 'natural' erosion controls. In the low-gradient study area, field borders exert control over the spatial reference of soil erosion and sedimentation sites. Over time, this brought about a growing historical and spatial contingency change to the soilscape, because of arbitrary spatial changes of the field system which are inherent in its socio-agricultural maintenance. Thus, the very low-gradient and low-erosivity setting of the study area have singled out the agency of human-induced spatial and connectivity controls and contingency for long-term spatial hillslope sediment flux. Although these findings may be less true for different settings, they allow for deriving a generic conceptual model of the linkages between 'natural' and anthropogenic subsystems to interpret the effects of long-term human-induced sediment flux. Accordingly, the resulting balance between on-hillslope net storage and net delivery to streams is scaling with basic physiographic properties of erosivity and sedimentation as well as the degree of anthropogenic hillslope fragmentation. For loess areas in Europe variable fields are fundamental anthropogeomorphic units that determine appropriate system scaling for historic sediment flux analysis and constrain retrodiction and prediction of changing fluxes at a point and a time at watershed scales. Methodical implications address adequate sampling strategies to record soilscape change, as a result of which a critical review of the applicability of the catena concept to long-cultivated hillslopes in central Europe was included. Finally, the suggested refined generic model of long-term, human-controlled sediment flux involves a number of research opportunities, particularly for linking modeling approaches to long-term field records of cultivation-related change in the soilscape.
Long-term oscillations of sunspots and a special class of artifacts in SOHO/MDI and SDO/HMI data
NASA Astrophysics Data System (ADS)
Efremov, V. I.; Solov'ev, A. A.; Parfinenko, L. D.; Riehokainen, A.; Kirichek, E.; Smirnova, V. V.; Varun, Y. N.; Bakunina, I.; Zhivanovich, I.
2018-03-01
A specific type of artifacts (named as " p2p"), that originate due to displacement of the image of a moving object along the digital (pixel) matrix of receiver are analyzed in detail. The criteria of appearance and the influence of these artifacts on the study of long-term oscillations of sunspots are deduced. The obtained criteria suggest us methods for reduction or even elimination of these artifacts. It is shown that the use of integral parameters can be very effective against the " p2p" artifact distortions. The simultaneous observations of sunspot magnetic field and ultraviolet intensity of the umbra have given the same periods for the long-term oscillations. In this way the real physical nature of the oscillatory process, which is independent of the artifacts have been confirmed again. A number of examples considered here confirm the dependence between the periods of main mode of the sunspot magnetic field long-term oscillations and its strength. The dependence was derived earlier from both the observations and the theoretical model of the shallow sunspot. The anti-phase behavior of time variations of sunspot umbra area and magnetic field of the sunspot demonstrates that the umbra of sunspot moves in long-term oscillations as a whole: all its points oscillate with the same phase.
Reliability and Engineering | Photovoltaic Research | NREL
-Time PV and Solar Resource Testing We study long-term performance, reliability, and failures of PV (NCPV) at NREL, we focus on photovoltaic (PV) reliability research and development (R&D) to improve PV technologies. We test modules and systems for long-term performance and stress them in the field
Long-Term Self-Regulation of Biology Learning Using Standard Junior High School Science Curriculum
ERIC Educational Resources Information Center
Eilam, Billie; Reiter, Shoshi
2014-01-01
In today's world of information explosion, independent lifelong self-regulated learning (SRL) is becoming a necessity. However, opportunities in schools to experience such learning modes are relatively rare. This long-term explorative field study examined students' SRL of science. Changes in students' self-reported and enacted SRL…
Long term durability of solid heartwood stakes treated with ACA or CCA
Mark E. Mankowski; Stan Lebow; Grant Kirker; Lee Gjovik
2017-01-01
Limited long-term field data exist evaluating the benefit of chemical wood preservatives on refractory wood species with abundant heartwood. The objective of this study was to determine the effectiveness of preservative-treated refractory solid heartwood comprised of southern pine, Douglas-fir, or Engelmann spruce. Non-incised and incised solid lumber of these species...
GATEWAY Demonstrations: Long-Term Evaluation of SSL Field Performance in Select Interior Projects
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, Tess E.; Davis, Robert G.; Wilkerson, Andrea M.
The GATEWAY program evaluated the long-term performance characteristics (chromaticity change, maintained illuminance, and operations and maintenance) of LED lighting systems in four field installations previously documented in separate DOE GATEWAY reports.
Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka
2013-10-01
Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the development of metapopulation models and provided an opportunity to test model predictions. This combination of empirical studies and modeling has facilitated the study of key phenomena in spatial dynamics, such as extinction threshold and extinction debt.
Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka
2013-01-01
Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the development of metapopulation models and provided an opportunity to test model predictions. This combination of empirical studies and modeling has facilitated the study of key phenomena in spatial dynamics, such as extinction threshold and extinction debt. PMID:24198935
Surgical Tooth Implants, Combat and Field.
1985-11-15
project in the development of dental implantology must not be overlooked. The early stages of this project clearly defined that rigid fixation of an...a long-term implant study of a serrated ceramic dental implant designed for fresh extraction sites. The baboon study was successfully completed last...materials. A series of graded dental implants have been produce’ to provide an interference fit in any fresh extraction site. The long-term implant
The QBO modulation of the occurrence of the Counter Electrojet
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pei-Ren Chen; Yi Luo; Jun Ma
1995-10-15
The authors report long term studies of the geomagnetic field made in India, looking at variations in the horizontal component of the field. In particular they look at the counter electrojet (CEJ), which is an observed reversal in the equatorial electrojet inferred from its impact on the geomagnetic field. They use their long time series datasets to correlate the CEJ with solar cycle variations and with the quasi-biennial oscillation.
Long-term field study of sea kraits in New Caledonia: fundamental issues and conservation.
Bonnet, Xavier
2012-08-01
This short review focuses on the findings associated with a long-term field study on two species of sea kraits in New Caledonia. Since 2002, more than 30 sites in the lagoon have been sampled, and in most places mark-recapture was implemented. We collected detailed data on more than 14,000 marked individuals (>6000 recaptures) and used different techniques (stable isotopes, bio-logging, analyses of diet). The objective was fundamental: to examine how amphibious snakes cope with both terrestrial and aquatic environments. As access to abundant food is likely the main evolutionary driver for the return transition toward the sea in marine tetrapods, foraging ecology was an important part of the research and novel information was obtained on this subject. Rapidly however, field observations revealed the potential interest of sea kraits for conservation issues. Our results show that these snakes are useful bio-indicators of marine biodiversity; they also provide a useful signal to monitor levels of contamination by heavy metals in the lagoon, and more generally as a means of studying the functioning of reef ecosystems. Importantly, anecdotal observations (e.g., a krait drinking during rain) provided unsuspected physiological insights of general importance to fundamental problems and conservation. One of the lessons of this long-term study is that key results emerged in an unexpected way, but all were dependent on intensive field work.
GATEWAY Report Brief: SSL Demonstration: Long-Term Evaluation of Indoor Field Performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
Report brief summarizing a GATEWAY program evaluation of the long-term performance characteristics (chromaticity change, maintained illuminance, and operations and maintenance) of LED lighting systems in four field installations previously documented in separate DOE GATEWAY reports.
Laura S. Kenefic; Christel C. Kern; John Brissette; Matthew Russell; Lloyd Irland; Aaron Weiskittel; Kate Berven
2013-01-01
Robert Lewis, former U.S. Forest Service Deputy Chief for Research and Development, used to say that "researchers leave tracks." By this he meant that part of the research process is recording all aspects of a study from initial plans to notes about installation and changes, as well as the raw data. This is especially important for long-term studies, which...
Hong S. He; Robert E. Keane; Louis R. Iverson
2008-01-01
Forest landscape models have become important tools for understanding large-scale and long-term landscape (spatial) processes such as climate change, fire, windthrow, seed dispersal, insect outbreak, disease propagation, forest harvest, and fuel treatment, because controlled field experiments designed to study the effects of these processes are often not possible (...
USDA-ARS?s Scientific Manuscript database
Long-term hydrologic data sets are required to quantify the impacts of management, and climate on runoff at the field scale where management practices are applied. This study was conducted to evaluate the impacts of long-term management and climate on runoff from a small watershed managed with no-ti...
Field of Study in College and Lifetime Earnings in the United States
Kim, ChangHwan; Tamborini, Christopher R.; Sakamoto, Arthur
2016-01-01
Our understanding about the relationship between education and lifetime earnings often neglects differences by field of study. Utilizing data that matches respondents in the Survey of Income and Program Participation to their longitudinal earnings records based on administrative tax information, we investigate the trajectories of annual earnings following the same individuals over 20 years and then estimate the long-term effects of field of study on earnings for U.S. men and women. Our results provide new evidence revealing large lifetime earnings gaps across field of study. We show important differences in individuals’ earnings trajectories across the different stages of the work-life by field of study. In addition, the gaps in 40-year (i.e., ages 20 to 59) median lifetime earnings among college graduates by field of study are larger, in many instances, than the median gap between high school graduates and college graduates overall. Significant variation is also found among graduate degree holders. Our results uncover important similarities and differences between men and women with regard to the long-term earnings differentials associated with field of study. In general, these findings underscore field of study as a critical dimension of horizontal stratification in educational attainment. Other implications of the empirical findings are also discussed. PMID:28042177
NASA Astrophysics Data System (ADS)
Virtanen, Ilpo; Mursula, Kalevi
2016-06-01
Aims: We study the long-term evolution of photospheric and coronal magnetic fields and the heliospheric current sheet (HCS), especially its north-south asymmetry. Special attention is paid to the reliability of the six data sets used in this study and to the consistency of the results based on these data sets. Methods: We use synoptic maps constructed from Wilcox Solar Observatory (WSO), Mount Wilson Observatory (MWO), Kitt Peak (KP), SOLIS, SOHO/MDI, and SDO/HMI measurements of the photospheric field and the potential field source surface (PFSS) model. Results: The six data sets depict a fairly similar long-term evolution of magnetic fields and the heliospheric current sheet, including polarity reversals and hemispheric asymmetry. However, there are time intervals of several years long, when first KP measurements in the 1970s and 1980s, and later WSO measurements in the 1990s and early 2000s, significantly deviate from the other simultaneous data sets, reflecting likely errors at these times. All of the six magnetographs agree on the southward shift of the heliospheric current sheet (the so-called bashful ballerina phenomenon) in the declining to minimum phase of the solar cycle during a few years of the five included cycles. We show that during solar cycles 20-22, the southward shift of the HCS is mainly due to the axial quadrupole term, reflecting the stronger magnetic field intensity at the southern pole during these times. During cycle 23 the asymmetry is less persistent and mainly due to higher harmonics than the quadrupole term. Currently, in the early declining phase of cycle 24, the HCS is also shifted southward and is mainly due to the axial quadrupole as for most earlier cycles. This further emphasizes the special character of the global solar field during cycle 23.
Long-term Kinetics of Uranyl Desorption from Sediments Under Advective Conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shang, Jianying; Liu, Chongxuan; Wang, Zheming
2014-02-15
Long-term (> 4 months) column experiments were performed to investigate the kinetics of uranyl (U(VI)) desorption in sediments collected from the Integrated Field Research Challenge (IFRC) site at the US Department of Energy (DOE) Hanford 300 Area. The experimental results were used to evaluate alternative multi-rate surface complexation reaction (SCR) approaches to describe the short- and long-term kinetics of U(VI) desorption under flow conditions. The SCR stoichiometry, equilibrium constants, and multi-rate parameters were independently characterized in batch and stirred flow-cell reactors. Multi-rate SCR models that were either additively constructed using the SCRs for individual size fractions (e.g., Shang et al.,more » 2011), or composite in nature could effectively describe short-term U(VI) desorption under flow conditions. The long-term desorption results, however, revealed that using a labile U concentration measured by carbonate extraction under-estimated desorbable U(VI) and the long-term rate of U(VI) desorption. An alternative modeling approach using total U as the desorbable U(VI) concentration was proposed to overcome this difficulty. This study also found that the gravel size fraction (2-8 mm), which is typically treated as non-reactive in modeling U(VI) reactive transport because of low external surface area, can have an important effect on the U(VI) desorption in the sediment. This study demonstrates an approach to effectively extrapolate U(VI) desorption kinetics for field-scale application, and identifies important parameters and uncertainties affecting model predictions.« less
NASA Astrophysics Data System (ADS)
Kuhwald, Michael; Augustin, Katja; Duttmann, Rainer
2017-04-01
The positive effects of reduced tillage on soil stability and on various soil functions such as infiltrability or saturated hydraulic conductivity are known in general. However, long-term employment of conservation tillage can increase weed pressure, damage by mice and soil compaction. Thus, the application of one-time inversion tillage (occasional or strategic tillage) is customarily used as a method for overcoming these drawbacks. Hitherto, the effects of one-time inversion tillage on soil physical properties have not been investigated. This study focuses on analysing whether the improved soil physical properties derived by long-term reduced tillage remain after one-time inversion tillage by mouldboard plough. The study was carried out in a 5.5 ha field in the southern part of Lower Saxony, Germany. Since 1996, this field has been subdivided into three plots, one managed conventionally by using a mouldboard plough (CT), while in the others a chisel plough (RT1) and a disk harrow (RT2) were employed. In October 2014, the entire field was ploughed by mouldboard plough to a depth of 30 cm. During the following year, four field studies were conducted to analyse the effects of this one-time inversion tillage on volumetric soil water content, bulk density, saturated hydraulic conductivity and infiltration rate. Additionally, penetration resistance measurements taken across the entire field were interpolated by kriging to analyse the spatial distribution of soil characteristics. The surveys of RT1 and RT2 were compared with CT and with analyses conducted before the one-time inversion tillage. This study shows that positive effects of long-term conservation tillage on several soil physical characteristics still remain after one-time mouldboard ploughing. Throughout the entire cropping season, the topsoil tilled under former conservation tillage practices revealed significantly higher (p < 0.05) values of saturated hydraulic conductivities and infiltration rates compared to the plot that experienced continuously conventional tillage. Moreover, field-wide measuring of penetration resistance indicated the removal of the compaction zone developed under conservation tillage in soil depths between 10 and 20 cm. After mouldboard ploughing, penetration resistance in the topsoil was significantly (p < 0.05) reduced in both plots, showing the same order of magnitude as measured in the conventionally managed plot. The results of this study suggest that one-time inversion tillage with a mouldboard plough offers a suitable management option for overcoming some of the main disadvantages associated with long-term conservation tillage, while conserving the improved soil physical properties and functions.
The long-term effectiveness of a FeSO4 + Na2S2O4 reductant solution blend for in situ saturated zone treatment of dissolved and solid phase Cr(VI) in a high pH chromite ore processing solid waste (COPSW) fill material was investigated. Two field pilot injection studies were cond...
Henry L. Gholz; David A. Wedin; Stephen M. Smitherman; Mark E. Harmon; William J. Parton
2000-01-01
We analysed data on mass loss after five years of decomposition in the field from both fine root and leaf litters from two highly contrasting trees, Drypetes glallca, a tropical hardwood tree from Puerto Rico, and pine species from North America as part of the Long-Term Intersite Decomposition Experiment (LIDET). LIDET is a reciprocal litterbag study...
Engineering and agronomy aspects of a long-term precision agriculture field experiment
USDA-ARS?s Scientific Manuscript database
Much research has been conducted on specific precision agriculture tools and implementation strategies, but little has been reported on long-term evaluation of integrated precision agriculture field experiments. In 2004 our research team developed and initiated a multi-faceted “precision agriculture...
Topical carbonic anhydrase inhibitors and visual function in glaucoma and ocular hypertension.
Gugleta, Konstantin
2010-06-01
Dorzolamide and brinzolamide are topical carbonic anhydrase inhibitors (CAI) indicated for patients with glaucoma and ocular hypertension. An evidence-based review of clinical trials of dorzolamide and brinzolamide was undertaken to determine an effect of these medications on visual function (primarily visual field) in open-angle glaucoma and ocular hypertension. Using the keywords 'dorzolamide' and 'brinzolamide', all articles describing trials of these medications reporting on visual acuity, contrast sensitivity and visual field from September 1966 to July 2009 were found in MEDLINE and EMBASE databases. No information from other sources was included in this review. A relatively modest number of trials was identified, where impact of therapy on one or more of the visual function modes was reported. In the studies of less than 1 year duration (3 days to 1 year, 23 studies) in all but three studies treatment with topical CAIs did not influence visual function, in two studies with dorzolamide some improvement in the contrast sensitivity was observed and in one open-label retrospective no-control-group study with dorzolamide visual field indices improved significantly. A different picture was seen in long-term studies, which were designed and powered to detect changes in visual field. One large study (European Glaucoma Prevention Study) with dorzolamide versus placebo failed to detect significant protective effect of the drug on glaucoma occurrence in ocular hypertensives. Several interesting aspects of this study are discussed in detail. The other two long-term studies reported on the superiority of adding dorzolamide over timolol therapy alone, and the superiority of the combination of dorzolamide and timolol over brinzolamide and timolol in terms of improving ocular blood flow (retrobulbar Color Doppler Imaging--CDI parameters) as well as in terms of visual field preservation in glaucoma patients over 4 to 5 years. For the first time one study could demonstrate that an improvement in ocular blood flow in the long run results in preservation of visual field in glaucoma patients. Dorzolamide, combined with the beta-blocker timolol, seems to be superior in this regard to brinzolamide plus timolol.
Brooks, Helen L; Rogers, Anne; Sanders, Caroline; Pilgrim, David
2015-03-01
Analyses of the experiences of chronic conditions demonstrate the importance of moral worth and social meaning linked to undertaking self-management practices. Rather less attention has been paid to the contemplation and significance of adopting, embedding and continuing with established practices overtime. This study explored perceptions about recovery and prognosis from the point of view of people with long-term physical health conditions and compared these findings with the mental health literature. A longitudinal qualitative study was conducted incorporating semi-structured interviews and thematic analysis. Thirty-two participants identified as having a chronic long-term physical health condition such as heart disease and diabetes were included in the study. In line with the notions of recovery in the mental health field, respondents viewed recovery as a complex journey related to the ability to undertake things of value in everyday life. However, there were differences in relation to reflections on trajectories and imagined futures centred on physical health. These findings are discussed in the context of literature from the mental and physical health fields and recent health policies for those with long-term conditions. The study adds to existing literature by examining the similarities and differences in the experience of chronic physical and mental health conditions. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
NASA Astrophysics Data System (ADS)
Lobo, Carlos M. S.; Tosin, Giancarlo; Baader, Johann E.; Colnago, Luiz A.
2017-10-01
In this article, several studies based on analytical expressions and computational simulations on Hollow Cylindrical Magnets with an external soft ferromagnetic material (HCM magnets) are presented. Electromagnetic configurations, as well as permanent-magnet-based structures, are studied in terms of magnetic field strength and homogeneity. Permanent-magnet-based structures are further analyzed in terms of the anisotropy of the magnetic permeability. It was found that the HCM magnets produce a highly homogeneous magnetic field as long as the magnetic material is isotropic. The dependency of the magnetic field strength and homogeneity in terms of the anisotropy of the magnetic permeability is also explored here. These magnets can potentially be used in medium-resolution NMR spectrometers and high-field NMR spectrometers.
Kaur, Ravinder; Paul, Madhumita; Malik, Rashmi
2007-06-01
Conjunctive use of saline/non-saline irrigation waters is generally aimed at minimizing yield losses and enhancing flexibility of cropping, without much alteration in farming operations. Recommendation of location-specific suitable conjunctive water use plans requires assessment of their long-term impacts on soil salinization/sodification and crop yield reductions. This is conventionally achieved through long-term field experiments. However such impact evaluations are site specific, expensive and time consuming. Appropriate decision support systems (DSS) can be time-efficient and cost-effective means for such long-term impact evaluations. This study demonstrates the application of one such (indigenously developed) DSS for recommending best conjunctive water use plans for a, rice-wheat growing, salt affected farmer's field in Gurgaon district of Haryana (India). Before application, the DSS was extensively validated on several farmers and controlled experimental fields in Gurgaon and Karnal districts of Haryana (India). Validation of DSS showed its potential to give realistic estimates of root zone soil salinity (with R = 0.76-0.94; AMRE = 0.03-0.06; RMSPD = 0.51-0.90); sodicity (with R = 0.99; AMRE = 0.02; RMSPD = 0.84) and relative crop yield reductions (AMRE = 0.24), under existing (local) resource management practices. Long term (10 years) root zone salt build ups and associated rice/wheat crop yield reductions, in a salt affected farmer's field, under varied conjunctive water use scenarios were evaluated with the validated DSS. It was observed that long-term applications of canal (CW) and tube well (TW) waters in a cycle and in 1:1 mixed mode, during Kharif season, predicted higher average root zone salt reductions (2-9%) and lower rice crop yield reductions (4-5%) than the existing practice of 3-CW, 3-TW, 3-CW. Besides this, long-term application of 75% CW mixed with 25% TW, during Rabi season, predicted about 17% lower average root-zone salt reductions than the cyclic applications of (1-CW, 1-TW, 2-CW) and (2-CW, 1-TW, 1-CW, i.e., existing irrigation strategy). However, average wheat crop yield reductions (16-17%) simulated under all these strategies were almost at par. In general, cyclic-conjunctive water use strategies emerged as better options than the blending modes. These results were in complete confirmation with actual long-term conjunctive water use experiments on similar soils. It was thus observed that such pre-validated tools could be efficient means for designing, local resource and target crop yield-specific, appropriate conjunctive water use plans for irrigated agricultural lands.
Long-term exposure to acidification disrupts reproduction in a marine invertebrate
Hattich, Giannina S. I.; Heinrichs, Mara E.; Pansch, Andreas; Zagrodzka, Zuzanna; Havenhand, Jonathan N.
2018-01-01
Climate change research is advancing to more complex and more comprehensive studies that include long-term experiments, multiple life-history stages, multi-population, and multi-trait approaches. We used a population of the barnacle Balanus improvisus known to be sensitive to short-term acidification to determine its potential for long-term acclimation to acidification. We reared laboratory-bred individuals (as singles or pairs), and field-collected assemblages of barnacles, at pH 8.1 and 7.5 (≈ 400 and 1600 μatm pCO2 respectively) for up to 16 months. Acidification caused strong mortality and reduced growth rates. Acidification suppressed respiration rates and induced a higher feeding activity of barnacles after 6 months, but this suppression of respiration rate was absent after 15 months. Laboratory-bred barnacles developed mature gonads only when they were held in pairs, but nonetheless failed to produce fertilized embryos. Field-collected barnacles reared in the laboratory for 8 months at the same pH’s developed mature gonads, but only those in pH 8.1 produced viable embryos and larvae. Because survivors of long-term acidification were not capable of reproducing, this demonstrates that B. improvisus can only partially acclimate to long-term acidification. This represents a clear and significant bottleneck in the ontogeny of this barnacle population that may limit its potential to persist in a future ocean. PMID:29408893
Stein, Alan; Desmond, Christopher; Garbarino, James; Van IJzendoorn, Marinus H; Barbarin, Oscar; Black, Maureen M; Stein, Aryeh D; Hillis, Susan D; Kalichman, Seth C; Mercy, James A; Bakermans-Kranenburg, Marian J; Rapa, Elizabeth; Saul, Janet R; Dobrova-Krol, Natasha A; Richter, Linda M
2014-07-01
The immediate and short-term consequences of adult HIV for affected children are well documented. Little research has examined the long-term implications of childhood adversity stemming from caregiver HIV infection. Through overviews provided by experts in the field, together with an iterative process of consultation and refinement, we have extracted insights from the broader field of child development of relevance to predicting the long-term consequences to children affected by HIV and AIDS. We focus on what is known about the impact of adversities similar to those experienced by HIV-affected children, and for which there is longitudinal evidence. Cautioning that findings are not directly transferable across children or contexts, we examine findings from the study of parental death, divorce, poor parental mental health, institutionalization, undernutrition, and exposure to violence. Regardless of the type of adversity, the majority of children manifest resilience and do not experience any long-term negative consequences. However, a significant minority do and these children experience not one, but multiple problems, which frequently endure over time in the absence of support and opportunities for recovery. As a result, they are highly likely to suffer numerous and enduring impacts. These insights suggest a new strategic approach to interventions for children affected by HIV and AIDS, one that effectively combines a universal lattice of protection with intensive intervention targeted to selected children and families.
Allen, A.W.; Cade, B.S.; Vandever, M.W.
2001-01-01
Successional changes in vegetation composition within seeded grasslands may effect attainment of long term conservaation objectives. Comparisons between vegetation composition within Conservation Reserve Program (CRP) fields planted to cool season, introduced grasses hayed for emergency we, and non hayed fields of the same age and species composition were completed to determine potential effects of periodic haying. Emergency haying had little long term effect on vegetation height/density, percent cover of live pass, or forb cover when compared to characteristics within non hayed fields?. The presence of legumes [primarily alfalfa (Medicago sativa L)] increased in response to haying, whereas, abundance of noxious weeds [chiefly Canada thistle (Cirsium arvense (L) Scop.)] diminished. Implications for long term management CRP grassland to achieve wildlife habitat objectives are discussed.
Management training in long-term care.
Evashwick, Connie
2002-01-01
The education of health care administrators faces its most dramatic change since the inception of the field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students for evidence-based practice. This paper presents recommendations for incorporating training about chronic and long-term care into health care management curricula. It asserts that all health care management students should have a basic knowledge of the fundamental policy, operating, and financing principles of long-term care. The majority of people using the health care delivery system today, and increasingly in the future, suffer from chronic conditions. Long-term care services, although less expansive in structure, far outnumber acute care services and health plans. They will grow in the future to meet the portending demand. To maximize job opportunities and to optimize performance in any job, health care administrators need to know about the long-term care delivery system. This paper delineates critical topics pertaining to long-term care, organized according to 11 fundamental management areas in which the field is developing core competencies. The contents were derived from a year-long process of asking stakeholders in the various facets of long-term care what topics they thought were essential for administrators to know. The topics delineated in this document represent the consensus about essential knowledge that all health care administrators should have about long-term care, whether specializing in long-term care or following a more general management career. The education of health care administrators faces its most dramatic change since the inception ofthe field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students to perform according to evidence-based practice. It is thus timely to consider content, as well as educational format. This paper presents recommendations for incorporating training about chronic and long-term care into health care administration curricula. It asserts that all health care administration students should have a basic knowledge of the fundamental policy, operating, and financing principles of long-term care.
NASA Astrophysics Data System (ADS)
Virtanen, I. O. I.; Virtanen, I. I.; Pevtsov, A. A.; Yeates, A.; Mursula, K.
2017-07-01
Aims: We aim to use the surface flux transport model to simulate the long-term evolution of the photospheric magnetic field from historical observations. In this work we study the accuracy of the model and its sensitivity to uncertainties in its main parameters and the input data. Methods: We tested the model by running simulations with different values of meridional circulation and supergranular diffusion parameters, and studied how the flux distribution inside active regions and the initial magnetic field affected the simulation. We compared the results to assess how sensitive the simulation is to uncertainties in meridional circulation speed, supergranular diffusion, and input data. We also compared the simulated magnetic field with observations. Results: We find that there is generally good agreement between simulations and observations. Although the model is not capable of replicating fine details of the magnetic field, the long-term evolution of the polar field is very similar in simulations and observations. Simulations typically yield a smoother evolution of polar fields than observations, which often include artificial variations due to observational limitations. We also find that the simulated field is fairly insensitive to uncertainties in model parameters or the input data. Due to the decay term included in the model the effects of the uncertainties are somewhat minor or temporary, lasting typically one solar cycle.
Chung, Woosuk; Park, Saegeun; Hong, Jiso; Park, Sangil; Lee, Soomin; Heo, Junyoung; Kim, Daesoo; Ko, Youngkwon
2015-10-01
To examine whether neonatal exposure to sevoflurane induces autism-like behaviors in mice. There are continuing reports regarding the potential negative effects of anesthesia on the developing brain. Recently, several studies suggest that neurotoxicity caused by anesthesia may lead to neurodevelopmental impairments. However, unlike reports focusing on learning and memory, there are only a few animal studies focusing on neurodevelopmental disorders after general anesthesia. Therefore, we have focused on autism, a representative neurodevelopmental disorder. Neonatal mice (P6-7) were exposed to a titrated dose of sevoflurane for 6 h. Apoptosis was evaluated by assessing the expression level of cleaved (activated) caspase-3. Autism-like behaviors, general activity, anxiety level, and long-term memory were evaluated with multiple behavioral assays. Western blotting confirmed that neonatal exposure to sevoflurane increased the expression level of activated caspase-3, indicative of apoptosis. Mice exposed to sevoflurane also showed impaired long-term memory in fear tests. However, sevoflurane-exposed mice did not exhibit autism-like features in all of the following assays: social interaction (three-chamber test, caged social interaction), social communication (ultrasonic vocalization test), or repetitive behavior (self-grooming test, digging). There were also no differences in general activity (open field test, home cage activity) and anxiety (open field test, light-dark box) after sevoflurane exposure. Our results confirm previous studies that neonatal sevoflurane exposure causes neurodegeneration and long-term memory impairment in mice. However, sevoflurane did not induce autism-like features. Our study suggests that mice are more vulnerable to long-term memory deficits than autism-like behaviors after exposure to sevoflurane. © 2015 John Wiley & Sons Ltd.
The evolving magnetic topology of τ Boötis
NASA Astrophysics Data System (ADS)
Mengel, M. W.; Fares, R.; Marsden, S. C.; Carter, B. D.; Jeffers, S. V.; Petit, P.; Donati, J.-F.; Folsom, C. P.; BCool Collaboration
2016-07-01
We present six epochs of spectropolarimetric observations of the hot-Jupiter-hosting star τ Boötis that extend the exceptional previous multiyear data set of its large-scale magnetic field. Our results confirm that the large-scale magnetic field of τ Boötis varies cyclicly, with the observation of two further magnetic reversals; between 2013 December and 2014 May and between 2015 January and March. We also show that the field evolves in a broadly solar-type manner in contrast to other F-type stars. We further present new results which indicate that the chromospheric activity cycle and the magnetic activity cycles are related, which would indicate a very rapid magnetic cycle. As an exemplar of long-term magnetic field evolution, τ Boötis and this long-term monitoring campaign presents a unique opportunity for studying stellar magnetic cycles.
LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER
Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...
Animal carcinogenicity studies on radiofrequency fields related to mobile phones and base stations.
Dasenbrock, Clemens
2005-09-01
Since a report in 1997 on an increased lymphoma incidence in mice chronically exposed to a mobile phone radiofrequency signal, none of the subsequent long-term studies in rodents have confirmed these results. On the other hand, several of the follow-up co- and carcinogenicity studies are still underway or are presently being initiated. Most of the published long-term studies used 1 exposure level only and suffer from a poor dosimetry which does not consider the animal's growth. Additional points of criticism are a limited, in some cases, questionable histopathology and inadequate group sizes. Overall, if dealing with new chemicals or drugs, these studies would not be acceptable for registration with the responsible authorities. The major critical points are taken into consideration within the European co- and carcinogenicity projects (CEMFEC and PERFORM-A), which are in their final stages and in the US long-term studies in mice and rats which are about to be initiated. Nevertheless, the WHO evaluation for health risk assessment of long-term telephone use and base station exposure will start in late 2005.
Greenslade, Penelope; Florentine, Singarayer K; Hansen, Brigita D; Gell, Peter A
2016-08-01
Monitoring forms the basis for understanding ecological change. It relies on repeatability of methods to ensure detected changes accurately reflect the effect of environmental drivers. However, operator bias can influence the repeatability of field and laboratory work. We tested this for invertebrates and diatoms in three trials: (1) two operators swept invertebrates from heath vegetation, (2) four operators picked invertebrates from pyrethrum knockdown samples from tree trunk and (3) diatom identifications by eight operators in three laboratories. In each trial, operators were working simultaneously and their training in the field and laboratory was identical. No variation in catch efficiency was found between the two operators of differing experience using a random number of net sweeps to catch invertebrates when sequence, location and size of sweeps were random. Number of individuals and higher taxa collected by four operators from tree trunks varied significantly between operators and with their 'experience ranking'. Diatom identifications made by eight operators were clustered together according to which of three laboratories they belonged. These three tests demonstrated significant potential bias of operators in both field and laboratory. This is the first documented case demonstrating the significant influence of observer bias on results from invertebrate field-based studies. Examples of two long-term trials are also given that illustrate further operator bias. Our results suggest that long-term ecological studies using invertebrates need to be rigorously audited to ensure that operator bias is accounted for during analysis and interpretation. Further, taxonomic harmonisation remains an important step in merging field and laboratory data collected by different operators.
USDA-ARS?s Scientific Manuscript database
Semiarid dryland crop yields with no-till, NT, residue management are often greater than stubble-mulch, SM, tillage as a result of improved soil conditions and water conservation, but information on long-term tillage effects on field hydrology and sustained crop production are needed. Our objective ...
Lobo, Carlos M S; Tosin, Giancarlo; Baader, Johann E; Colnago, Luiz A
2017-10-01
In this article, several studies based on analytical expressions and computational simulations on Hollow Cylindrical Magnets with an external soft ferromagnetic material (HCM magnets) are presented. Electromagnetic configurations, as well as permanent-magnet-based structures, are studied in terms of magnetic field strength and homogeneity. Permanent-magnet-based structures are further analyzed in terms of the anisotropy of the magnetic permeability. It was found that the HCM magnets produce a highly homogeneous magnetic field as long as the magnetic material is isotropic. The dependency of the magnetic field strength and homogeneity in terms of the anisotropy of the magnetic permeability is also explored here. These magnets can potentially be used in medium-resolution NMR spectrometers and high-field NMR spectrometers. Copyright © 2017 Elsevier Inc. All rights reserved.
34 CFR 386.1 - What is the Rehabilitation Long-Term Training program?
Code of Federal Regulations, 2014 CFR
2014-07-01
... advanced training leading to an academic degree in one of those fields of study identified in paragraph (b) of this section; (2) Projects that provide a specified series of courses or program of study leading to award of a certificate in one of those fields of study identified in paragraph (b) of this section...
34 CFR 386.1 - What is the Rehabilitation Long-Term Training program?
Code of Federal Regulations, 2011 CFR
2011-07-01
... advanced training leading to an academic degree in one of those fields of study identified in paragraph (b) of this section; (2) Projects that provide a specified series of courses or program of study leading to award of a certificate in one of those fields of study identified in paragraph (b) of this section...
34 CFR 386.1 - What is the Rehabilitation Long-Term Training program?
Code of Federal Regulations, 2013 CFR
2013-07-01
... advanced training leading to an academic degree in one of those fields of study identified in paragraph (b) of this section; (2) Projects that provide a specified series of courses or program of study leading to award of a certificate in one of those fields of study identified in paragraph (b) of this section...
34 CFR 386.1 - What is the Rehabilitation Long-Term Training program?
Code of Federal Regulations, 2012 CFR
2012-07-01
... advanced training leading to an academic degree in one of those fields of study identified in paragraph (b) of this section; (2) Projects that provide a specified series of courses or program of study leading to award of a certificate in one of those fields of study identified in paragraph (b) of this section...
Chemical stabilization of metals and arsenic in contaminated soils using oxides--a review.
Komárek, Michael; Vaněk, Aleš; Ettler, Vojtěch
2013-01-01
Oxides and their precursors have been extensively studied, either singly or in combination with other amendments promoting sorption, for in situ stabilization of metals and As in contaminated soils. This remediation option aims at reducing the available fraction of metal(loid)s, notably in the root zone, and thus lowering the risks associated with their leaching, ecotoxicity, plant uptake and human exposure. This review summarizes literature data on mechanisms involved in the immobilization process and presents results from laboratory and field experiments, including the subsequent influence on higher plants and aided phytostabilization. Despite the partial successes in the field, recent knowledge highlights the importance of long-term and large-scale field studies evaluating the stability of the oxide-based amendments in the treated soils and their efficiency in the long-term. Copyright © 2012 Elsevier Ltd. All rights reserved.
DETERMINING THE EFFECTIVENESS OF DREDGING: FIELD STUDY FOR EVALUATING DREDGING RESIDUALS
Dredging is a commonly selected remedy for the risk management of contaminated sediments. Even so, there are questions regarding both the short-term and long-term effectiveness of dredging. A significant aspect in the performance of dredging is dredging residuals. Post-dredging ...
LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS - PRESENTATION
Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...
Long-Term Effects of Orthophosphate Treatment on Copper Concentration
Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility, and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...
LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS
Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...
Braun, M Miles
2013-10-01
Study of complementary and alternative medicine's mind and body interventions (CAM-MABI) is hindered not only by the inability to mask participants and their teachers to the study intervention but also by the major practical hurdles of long-term study of practices that can be lifelong. Two other important methodological problems are that study of newly trained practitioners cannot directly address long-term practice, and that long-term practitioners likely self-select in ways that make finding appropriate controls (or a comparison group) challenging. The temporary practice pause then resumption study design (TPPR) introduced here is a new tool that extends the withdrawal study design, established in the field of drug evaluation, to the field of CAM-MABI. With the exception of the inability to mask, TPPR can address the other methodological problems noted above. Of great interest to investigators will likely be measures in practitioners of CAM-MABI that change with temporary pausing of CAM-MABI practice, followed by return of the measures to pre-pause levels with resumption of practice; this would suggest a link of the practice to measured changes. Such findings using this tool may enhance our insight into fundamental biological processes, leading to beneficial practical applications.
Lower thermosphere (80-100 km) dynamics response to solar and geomagnetic activity: Overview
NASA Technical Reports Server (NTRS)
Kazimirovsky, E. S.
1989-01-01
The variations of solar and geomagnetic activity may affect the thermosphere circulation via plasma heating and electric fields, especially at high latitudes. The possibility exists that the energy involved in auroral and magnetic storms can produce significant changes of mesosphere and lower thermosphere wind systems. A study of global radar measurements of winds at 80 to 100 km region revealed the short term effects (correlation between wind field and geomagnetic storms) and long term variations over a solar cycle. It seems likely that the correlation results from a modification of planetary waves and tides propagated from below, thus altering the dynamical regime of the thermosphere. Sometimes the long term behavior points rather to a climatic variation with the internal atmospheric cause than to a direct solar control.
Promoting Field Trip Confidence: Teachers Providing Insights for Pre-Service Education
ERIC Educational Resources Information Center
Ateskan, Armagan; Lane, Jennie F.
2016-01-01
Pre-service teachers need experiences in practical matters as a part of field trip preparations programmes. For 14 years, a private, non-profit university in Turkey has involved pre-service teachers in field trip planning, implementation and evaluation. A programme assessment was conducted through a case study to examine the long-term effects of…
Unified pre- and postsynaptic long-term plasticity enables reliable and flexible learning.
Costa, Rui Ponte; Froemke, Robert C; Sjöström, P Jesper; van Rossum, Mark Cw
2015-08-26
Although it is well known that long-term synaptic plasticity can be expressed both pre- and postsynaptically, the functional consequences of this arrangement have remained elusive. We show that spike-timing-dependent plasticity with both pre- and postsynaptic expression develops receptive fields with reduced variability and improved discriminability compared to postsynaptic plasticity alone. These long-term modifications in receptive field statistics match recent sensory perception experiments. Moreover, learning with this form of plasticity leaves a hidden postsynaptic memory trace that enables fast relearning of previously stored information, providing a cellular substrate for memory savings. Our results reveal essential roles for presynaptic plasticity that are missed when only postsynaptic expression of long-term plasticity is considered, and suggest an experience-dependent distribution of pre- and postsynaptic strength changes.
Comparative study on five different commercial extenders for boar semen.
Vyt, P; Maes, D; Dejonckheere, E; Castryck, F; Van Soom, A
2004-02-01
Increasing interest in a longer preservation of diluted boar sperm raises questions in the field concerning the choice of the extender. The aim of this study was to evaluate the longevity of boar sperm extended in currently used commercial semen extenders. Three long-term extenders and two short-term extenders were compared for different semen quality parameters that can be assessed under routine laboratory conditions. Sperm morphology, motility, pH and bacteriological contamination were investigated during a 7-day period. The number of dead spermatozoa did not differ significantly among the extenders (p > 0.05). Sperm motility was not only related with storage period but most of all with pH, especially in long-term extenders. Differences between the different extenders were prominent (p < 0.05); the sperm preserved in only one long-term extender showed good motility during the whole test period. In all cases, the pH of the extended semen increased by 0.3-0.5 in the first days of storage and was significantly correlated with a decrease in motility. Bacteriological quality had no significant influence on motility or pH of the semen. In conclusion, we can state that in both short-term extenders and in only one long-term extender, sperm longevity, as evaluated by the parameters used in this study, was sufficient during the preservation period. To preserve the quality of diluted boar semen during long-term storage, the choice of the long-term extender is important. In addition, the monitoring of the pH of extended boar semen in our study emphasizes the importance of the buffering capacity of semen extenders.
Shahid, Muhammad; Arshad, Muhammad; Kaemmerer, Michel; Pinelli, Eric; Probst, Anne; Baque, David; Pradere, Philippe; Dumat, Camille
2012-01-01
The long length of periods required for effective soil remediation via phytoextraction constitutes a weak point that reduces its industrial use. However, these calculated periods are mainly based on short-term and/or hydroponic controlled experiments. Moreover, only a few studies concern more than one metal, although soils are scarcely polluted by only one element. In this scientific context, the phytoextraction of metals and metalloids (Pb, Cd, Zn, Cu, and As) by Pelargonium was measured after a long-term field experiment. Both bulk and rhizosphere soils were analyzed in order to determine the mechanisms involved in soil-root transfer. First, a strong increase in lead phytoextraction was observed with plant maturity, significantly reducing the length of the period required for remediation. Rhizosphere Pb, Zn, Cu, Cd, and As accumulation was observed (compared to bulk soil), indicating metal mobilization by the plant, perhaps in relation to root activity. Moreover, metal phytoextraction and translocation were found to be a function of the metals' nature. These results, taken altogether, suggest that Pelargonium could be used as a multi-metal hyperaccumulator under multi-metal soil contamination conditions, and they also provide an interesting insight for improving field phytoextraction remediation in terms of the length of time required, promoting this biological technique.
USDA-ARS?s Scientific Manuscript database
Long-term fertilization strategies have been proven to significantly influence soil organic carbon (SOC) accumulation, while the underlying mechanism remains unclear. Using two long-term (>20 y) field experiments of a double-cropped maize-wheat rotation on a Calcaric Fluvisol and paddy rice on a Hyd...
Studies of physiology and the morphology of the cat LGN following proton irradiation.
Reder, C S; Moyers, M F; Lau, D; Kirby, M A
2000-03-15
We have examined the effects of proton irradiation on the histologic and receptive field properties of thalamic relay cells in the cat visual system. The cat lateral geniculate nucleus (LGN) is a large structure with well-defined anatomical boundaries, and well-described afferent, efferent, and receptive field properties. A 1.0-mm proton microbeam was used on the cat LGN to determine short-term (3 months) and long-term (9 months) receptive field effects of irradiation on LGN relay cells. The doses used were 16-, 40-, and 60-gray (Gy). Following irradiation, abnormalities in receptive field organization were found in 40- and 60-Gy short-term animals, and in all of the long-term animals. The abnormalities included "silent" areas of the LGN where a visual response could not be evoked and other regions that had unusually large or small compound receptive fields. Histologic analysis failed to identify cellular necrosis or vascular damage in the irradiated LGN, but revealed a disruption in retinal afferents to areas of the LGN. These results indicate that microbeam proton irradiation can disrupt cellular function in the absence of obvious cellular necrosis. Moreover, the area and extent of this disruption increased with time, having larger affect with longer post-irradiation periods.
ERIC Educational Resources Information Center
Dadgar, Mina; Trimble, Madeline Joy
2015-01-01
This study provides one of the first estimates of the returns to different types of community college credentials--short-term certificates, long-term certificates, and associate degrees--across different fields of study. We exploit a rich data set that includes matched, longitudinal college transcripts and Unemployment Insurance records for…
Kim, Hyun-Bum; Kwon, Byeong-Jae; Cho, Hyun-Ji; Kim, Ji-Won; Chon, Jeong-Woo; Do, Moon-Ho; Park, Sang-Yong; Kim, Sun-Yeou; Maeng, Sung-Ho; Park, Yoo-Kyoung; Park, Ji-Ho
2015-03-01
Artemisia princeps (AP) is a flowering perennial used as a traditional medicine and dietary supplement across East Asia. No study has yet assessed its effects on synaptic plasticity in hippocampus and much less in a model of ovarian hormone deficiency. We examined the influence of chronic oral AP ethanol extract treatment in ovariectomized rats on the induction of long-term depression in a representative synapse (CA3-CA1) of the hippocampus. Ovariectomized rats demonstrated lower trabecular mean bone mineral densities than sham, validating the establishment of pathology. Against this background of pathology, AP-treated ovariectomized rats exhibited attenuated long-term depression (LTD) in CA1 relative to water-treated controls as measured by increased field excitatory post-synaptic potentials (fEPSP) activation averages over the post-stimulation period. While pathological significance of long-term depression (LTD) in ovariectomized rats is conflicting, that AP treatment significantly affected its induction offers justification for further study of its influences on plasticity and its related disorders.
2008-09-30
developing methods to simultaneously track multiple vocalizing marine mammals, we hope to contribute to the fields of marine mammal bioacoustics, ecology ...mammals, we hope to contribute to the fields of marine mammal bioacoustics, ecology , and anthropogenic impact mitigation. 15. SUBJECT TERMS 16. SECURITY...N00014-05-1-0074 (OA Graduate Traineeship for E-M Nosal) LONG-TERM GOALS The long-term goal of our research is to develop algorithms that use widely
The effects of short- and long-term air pollutants on plant phenology and leaf characteristics.
Jochner, Susanne; Markevych, Iana; Beck, Isabelle; Traidl-Hoffmann, Claudia; Heinrich, Joachim; Menzel, Annette
2015-11-01
Pollution adversely affects vegetation; however, its impact on phenology and leaf morphology is not satisfactorily understood yet. We analyzed associations between pollutants and phenological data of birch, hazel and horse chestnut in Munich (2010) along with the suitability of leaf morphological parameters of birch for monitoring air pollution using two datasets: cumulated atmospheric concentrations of nitrogen dioxide and ozone derived from passive sampling (short-term exposure) and pollutant information derived from Land Use Regression models (long-term exposure). Partial correlations and stepwise regressions revealed that increased ozone (birch, horse chestnut), NO2, NOx and PM levels (hazel) were significantly related to delays in phenology. Correlations were especially high when rural sites were excluded suggesting a better estimation of long-term within-city pollution. In situ measurements of foliar characteristics of birch were not suitable for bio-monitoring pollution. Inconsistencies between long- and short-term exposure effects suggest some caution when interpreting short-term data collected within field studies. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Harutyunyan, Hayk A.; Sahakyan, Gohar V.
2016-01-01
The aim of this study was to determine activities of pro-/antioxidant enzymes, reactive oxygen species (ROS) content, and oxidative modification of proteins and lipids in red blood cells (RBCs) and blood plasma of rats exposed to electrostatic field (200 kV/m) during the short (1 h) and the long periods (6 day, 6 h daily). Short-term exposure was characterized by the increase of oxidatively damaged proteins in blood of rats. This was strongly expressed in RBC membranes. After long-term action, RBC content in peripheral blood was higher than in control ( P < 0.01) and the attenuation of prooxidant processes was shown.
ERIC Educational Resources Information Center
Farmer, James; Knapp, Doug; Benton, Gregory M.
2007-01-01
Using phenomenological analysis, the authors examined the long-term effects of an environmental education school field trip on fourth grade elementary students who visited Great Smoky Mountains National Park. The authors' findings suggest that one year after the experience, many students remembered what they had seen and heard and had developed a…
Hurtado, Johanna; Clark, David B
2011-12-01
Most field ecology is conceived and financed by scientists from urban areas but is actually carried out in rural areas. Field staff can either be imported from urban areas or recruited from local residents. We evaluated the advantages and disadvantages of involving rural residents as local technicians over a 25- year period at active field research site in Costa Rica. We defined "local technicians" as local residents with no university education who acquired significant experience in field data collection, data management and/or laboratory work. We analyzed the experiences of incorporating these technicians into field research in developing countries from the points of view of scientist and of the local technicians themselves. Primary data were written responses from to a standardized survey of 19 senior scientists and Ph.D. students,and results from standardized personal interviews with 22 local technicians. Researchers highlighted the advantages of highly-skilled technicians with minimal staff turnover, as well as the technicians' knowledge of local ecological conditions. Local technicians considered the primary advantages of their jobs to be opportunities for continuing education training in science as well as cultural enrichment through interactions with people of different cultures. The main challenges identified by researchers were the lack of long-term funding for projects and extended training required for local technicians. Local technicians can be of great benefit to research projects by providing high-quality data collection at reasonable costs with low staff turnover. Over the last 25 years the research model at the field station we studied has evolved to the point that most long-term projects now depend heavily on local technicians. This model of involving local technicians in long-term research has multiple benefits for the researchers, the technicians and the local community, and could be adapted to a variety of settings in rural areas of developing countries.
Long term field evaluation reveals HLB resistance in Citrus relatives
USDA-ARS?s Scientific Manuscript database
Citrus huanglongbing (HLB) is a destructive disease with no known cure. To identify sources of HLB resistance in the subfamily Aurantioideae to which citrus belongs, we conducted a six-year field trial under natural disease challenge conditions in an HLB endemic region. The study included 65 Citrus ...
Plate convergence and long-term crustal deformation in central Japan
NASA Astrophysics Data System (ADS)
Heki, Kosuke; Miyazaki, Shin'ichi
Surveys by continuous Global Positioning System in and around Japan revealed that the Amurian Plate collides with the North American Plate in central Japan by ∼2 cm/yr. Long-term crustal deformation seems to be influenced mainly by this collision although subduction of oceanic plates governs short-term elastic deformation over the arc. Here we study the long-term deformation field by carefully removing the short-term signals inferred from a-priori plate convergence vectors and coupling strengths predicted by a thermal model. The obtained field shows that the change in velocities occurs along the longitude 135° ∼ 137°, and there exist a relatively rigid block and zones accommodating strains. Characteristic compressional deformation is found northwest of Izu due possibly to the collision of the Izu-Bonin arc with Honshu. Plate convergence rate along the Nankai-Suruga Trough is considerably smaller in eastern parts, due partly to the transition from the Amurian to the North American Plate of the landward side, and partly to the motion of the Izu Microplate relative to the Philippine Sea Plate. This accounts for longer recurrence intervals of interplate earthquakes in the Suruga Trough where the Tokai earthquake is anticipated to occur.
Narożna, Dorota; Pudełko, Krzysztof; Króliczak, Joanna; Golińska, Barbara; Sugawara, Masayuki; Mądrzak, Cezary J.
2015-01-01
It was previously demonstrated that there are no indigenous strains of Bradyrhizobium japonicum forming nitrogen-fixing root nodule symbioses with soybean plants in arable field soils in Poland. However, bacteria currently classified within this species are present (together with Bradyrhizobium canariense) as indigenous populations of strains specific for nodulation of legumes in the Genisteae tribe. These rhizobia, infecting legumes such as lupins, are well established in Polish soils. The studies described here were based on soybean nodulation field experiments, established at the Poznań University of Life Sciences Experiment Station in Gorzyń, Poland, and initiated in the spring of 1994. Long-term research was then conducted in order to study the relation between B. japonicum USDA 110 and USDA 123, introduced together into the same location, where no soybean rhizobia were earlier detected, and nodulation and competitive success were followed over time. Here we report the extra-long-term saprophytic survival of B. japonicum strains nodulating soybeans that were introduced as inoculants 20 years earlier and where soybeans were not grown for the next 17 years. The strains remained viable and symbiotically competent, and molecular and immunochemical methods showed that the strains were undistinguishable from the original inoculum strains USDA 110 and USDA 123. We also show that the strains had balanced numbers and their mobility in soil was low. To our knowledge, this is the first report showing the extra-long-term persistence of soybean-nodulating strains introduced into Polish soils and the first analyzing the long-term competitive relations of USDA 110 and USDA 123 after the two strains, neither of which was native, were introduced into the environment almost 2 decades ago. PMID:26048934
Narożna, Dorota; Pudełko, Krzysztof; Króliczak, Joanna; Golińska, Barbara; Sugawara, Masayuki; Mądrzak, Cezary J; Sadowsky, Michael J
2015-08-15
It was previously demonstrated that there are no indigenous strains of Bradyrhizobium japonicum forming nitrogen-fixing root nodule symbioses with soybean plants in arable field soils in Poland. However, bacteria currently classified within this species are present (together with Bradyrhizobium canariense) as indigenous populations of strains specific for nodulation of legumes in the Genisteae tribe. These rhizobia, infecting legumes such as lupins, are well established in Polish soils. The studies described here were based on soybean nodulation field experiments, established at the Poznań University of Life Sciences Experiment Station in Gorzyń, Poland, and initiated in the spring of 1994. Long-term research was then conducted in order to study the relation between B. japonicum USDA 110 and USDA 123, introduced together into the same location, where no soybean rhizobia were earlier detected, and nodulation and competitive success were followed over time. Here we report the extra-long-term saprophytic survival of B. japonicum strains nodulating soybeans that were introduced as inoculants 20 years earlier and where soybeans were not grown for the next 17 years. The strains remained viable and symbiotically competent, and molecular and immunochemical methods showed that the strains were undistinguishable from the original inoculum strains USDA 110 and USDA 123. We also show that the strains had balanced numbers and their mobility in soil was low. To our knowledge, this is the first report showing the extra-long-term persistence of soybean-nodulating strains introduced into Polish soils and the first analyzing the long-term competitive relations of USDA 110 and USDA 123 after the two strains, neither of which was native, were introduced into the environment almost 2 decades ago. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Blue Whale Behavioral Response Study and Field Testing of the New Bioacoustic Probe
2011-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Blue Whale Behavioral Response Study & Field Testing of...6849 email: jhildebrand@ucsd.edu Award Number: N000140811221 LONG-TERM GOALS Task 1: Blue Whales Behavioral Response Study The...behavioral response of large whales to commercial shipping and other low-frequency anthropogenic sound is not well understood. The PCAD model (NRC 2005
Micro patterned surfaces allow long-term digital holographic microscopy live cell imaging
NASA Astrophysics Data System (ADS)
Mues, Sarah; Lilge, Inga; Schönherr, Holger; Kemper, Björn; Schnekenburger, Jürgen
2017-07-01
During long-term imaging, cells move out of the field of view. We have generated functionalized substrates containing rectangular areas, which were capable in keeping cells over the whole observation period.
ERIC Educational Resources Information Center
Dadgar, Mina; Weiss, Madeline Joy
2012-01-01
This study provides one of the first estimates of the returns to different types of community college credentials--short-term certificates, long-term certificates, and associate degrees--across different fields of study. We exploit a rich dataset that includes matched, longitudinal college transcripts and Unemployment Insurance records for…
Badowska-Szalewska, E; Spodnik, E; Ludkiewicz, B; Klejbor, I; Moryś, J
2011-12-29
This study aimed at examining and comparing the influence of two different stress stimuli on the density (number of cells/mm²) of nerve growth factor (NGF) containing neurons in the hippocampal CA1 and CA3 pyramidal cell layers and the dentate gyrus (DG) granule cell layer in juvenile rats (P28; P-postnatal day). The high-light open-field (HL-OF) test and forced swim (FS) test were employed to investigate the effects of a single, 15-min acute exposure and repeated (15 min daily for 21 days) long-term exposure to stress. In order to detect NGF-ir neurons, immunohistochemical (-ir) techniques were used. In comparison with nonstressed animals, acute and long-term HL-OF or FS stimulation resulted in a marked increase (P<0.001) in the density of NGF-ir containing cells in all the hippocampal structures. The frequency of stress application (acute vs. long-term), however, did not have a substantial impact on the studied parameter, with the exception of the CA3 sector, where a decreased density (P<0.001) of NGF-ir neurons was observed after long-term exposure to FS. It may be concluded that a rise in the density of NGF-ir neurons in the juvenile rat hippocampus after exposure to HL-OF or FS stressors could have affected the activity of the hypothalamic-pituitary-adrenocortical (HPA) stress axis. Prolonged HL-OF or FS stress was probably aggravating enough not to trigger the habituation process. The type of stressor applied (HL-OF vs. FS) was not essentially a factor determining the density of NGF-ir cells in the hippocampus. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.
Amplicon-Based Sequencing of Soil Fungi from Wood Preservative Test Sites
Kirker, Grant T.; Bishell, Amy B.; Jusino, Michelle A.; Palmer, Jonathan M.; Hickey, William J.; Lindner, Daniel L.
2017-01-01
Soil samples were collected from field sites in two AWPA (American Wood Protection Association) wood decay hazard zones in North America. Two field plots at each site were exposed to differing preservative chemistries via in-ground installations of treated wood stakes for approximately 50 years. The purpose of this study is to characterize soil fungal species and to determine if long term exposure to various wood preservatives impacts soil fungal community composition. Soil fungal communities were compared using amplicon-based DNA sequencing of the internal transcribed spacer 1 (ITS1) region of the rDNA array. Data show that soil fungal community composition differs significantly between the two sites and that long-term exposure to different preservative chemistries is correlated with different species composition of soil fungi. However, chemical analyses using ICP-OES found levels of select residual preservative actives (copper, chromium and arsenic) to be similar to naturally occurring levels in unexposed areas. A list of indicator species was compiled for each treatment-site combination; functional guild analyses indicate that long-term exposure to wood preservatives may have both detrimental and stimulatory effects on soil fungal species composition. Fungi with demonstrated capacity to degrade industrial pollutants were found to be highly correlated with areas that experienced long-term exposure to preservative testing. PMID:29093702
Nemeth, Denise; Lambrinos, John G; Strik, Bernadine C
2017-02-01
Perennial crops potentially provide a sink for atmospheric carbon. However, there is a poor understanding of how perennial crops differ in their carbon allocation patterns, and few studies have tested how agronomic practices such as fertilization influence long-term patterns of carbon allocation in actual production systems. In this study, we report results of a long-term field experiment that tested the individual and combined effects of organic matter incorporation and nitrogen fertilization on carbon allocation. The mature (nine-year-old) blueberry plants in this study had an average standing carbon stock of 1147gCm -2 and average annual Net Primary Production (NPP) of 523gCm -2 yr -1 , values that are similar to those reported for other woody crops. Forty-four percent of blueberry annual NPP was sequestered in persistent biomass, 19% was exported as harvested fruit, and 37% entered the detrital pathway. Nitrogen applied at rates typical for blueberry production throughout the span of the study had no significant effect on total plant or soil C. However, pre-planting organic matter incorporation and periodic mulching with sawdust significantly increased both soil organic matter and soil C. Pre-planting organic matter incorporation also increased total standing plant C nine years later at maturity. At the field scale, we estimate that fields receiving pre-planting organic matter incorporation would have 4.8% (4.5Mgha -1 ) more standing C relative to non-amended fields, although the difference is within the range of uncertainty of the estimated values. These results suggest that blueberry production can provide a valuable medium-term carbon store that is comparable in magnitude to that of temperate tree crops, but overall carbon budgets are influenced by management practices over the first decade after planting. Copyright © 2016 Elsevier B.V. All rights reserved.
A Descriptive, Multiyear Examination of Positive Behavior Support
ERIC Educational Resources Information Center
Dunlap, Glen; Carr, Edward G.; Horner, Robert H.; Koegel, Robert L.; Sailor, Wayne; Clarke, Shelley; Koegel, Lynn Kern; Albin, Richard W.; Vaughn, Bobbie J.; McLaughlin, Darlene Magito; James, Kim Mullen; Todd, Anne W.; Newton, J. Stephen; Lucyshyn, Joseph; Griggs, Peter; Bohanon, Hank; Choi, Jeong Hoon; Vismara, Laurie; Minjarez, Mendy Boettcher; Buschbacher, Pamelazita; Fox, Lise
2010-01-01
A major goal of positive behavior support (PBS) is to produce broad-based, long-term improvements in adaptive behavior; however, the empirical base, at present, is mainly composed of relatively short-term studies carried out in circumscribed contexts. Therefore, a need exists for reliable data that can inform the field regarding the comprehensive…
USDA-ARS?s Scientific Manuscript database
The calibration and validation of soil moisture remote sensing products is complicated by the logistics of installing a soil moisture network for a long term period in an active landscape. Therefore, these stations are located along field boundaries or in non-representative sites with regards to so...
Mechan, Annis O; Moran, Paula M; Elliott, MartinJ; Young, Andrew J; Joseph, Michael H; Green, RichardA
2002-01-01
Decreased 5-HT function has been shown to induce behaviour consistent with an "anxiolytic" effect. Administration of a single dose of 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy" 12.5 mg/kg IP) to rats results in prolonged damage to central serotonergic nerve terminals. Thus we wished to assess whether an MDMA-induced lesion may have longer-term behavioural consequences. The study was designed to examine the behaviour of MDMA-pretreated and control animals in the elevated plus-maze and open field at a number of time-points, up to 80 days, after the administration of a single neurotoxic dose of MDMA (12.5 mg/kg IP). MDMA-pretreated Dark Agouti rats demonstrated a statistically significant reduction in anxiety-related behaviour, compared to saline-pretreated control rats, in both the elevated plus-maze and open field when the rats were tested on day 73 (open field) and day 80 (plus maze) after MDMA administration. The behavioural consequences of a single neurotoxic dose of MDMA can be demonstrated over 2 months after administration of the compound, thereby indicating that long-term adaptive changes occur within the brain following the neurodegeneration of 5-HT neurones produced by this recreationally used drug.
Different influences of field aging on nickel toxicity to Folsomia candida in two types of soil.
Liu, Yu-Rong; Li, Jing; He, Ji-Zheng; Ma, Yi-Bing; Zheng, Yuan-Ming
2015-06-01
Metal aging in soils has been considered an important factor influencing its availability and toxicity to organisms. In this study, we report the influence of 5 years field aging on the nickel (Ni) toxicity to collembolan Folsomia candida based on two different types of soil from Dezhou (DZ) and Qiyang (QY) counties in China. Acute and chronic toxicity of Ni to F. candida was assessed in both freshly spiked and field aging contaminated soils. We found that 5 years field aging increased the EC50 and 2d-LC50 values of Ni to F. candida in the DZ soil, while little influence on the Ni toxicity was observed in the QY soil. There was no adverse effect of the long-term field aging on the Ni toxicity to the survival of F. candida in the two tested soils. In addition, field aging of the two soils impacted differently the water-soluble Ni concentrations, which were significantly correlated to the juvenile production of F. candida based on a logistic model. Our study highlights different effects of long-term field aging on the Ni toxicity to F. candida between divergent types of soil, and this should be taken into account in future toxicity testing and risk assessment practices.
1979-07-01
microplasmodial cultures continuously subjected to the particular field conditions being studied. The stages in ’ ,oitotic cycle ,re determined by observing...of the decrease in rate varies with exposure conditions . Mean values of the decreases computed from the raw data are given on the righthand side of...exposures we were concerned about was the effect of long-term, chronic exposure. Figure 2 presents data for field conditions that are the same as
Blue Whale Behavioral Response Study & Field Testing of the New Bioacoustic Probe
2012-09-30
L. T. HATCH and C. W. CLARK. 2003. Variation in humpback whale (Megaptera novaeangliae) song length in relation to low-frequency sound broadcasts...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Blue Whale Behavioral Response Study & Field Testing of...ucsd.edu Award Number: N000140811221 LONG-TERM GOALS Task 1: Blue Whales Behavioral Response Study The behavioral response of large whales
Ostaszkiewicz, Joan; O'Connell, Beverly; Dunning, Trisha
2016-09-01
To systematically examine, describe and explain how continence care was determined, delivered and communicated in Australian long aged care facilities. Incontinence is a highly stigmatising condition that affects a disproportionally large number of people living in long-term aged care facilities. Its day-to-day management is mainly undertaken by careworkers. We conducted a Grounded theory study to explore how continence care was determined, delivered and communicated in long-term aged care facilities. This paper presents one finding, i.e. how careworkers in long-term aged care facilities deal with the stigma, devaluation and the aesthetically unpleasant aspects of their work. Grounded theory. Eighty-eight hours of field observations in two long-term aged care facilities in Australia. In addition, in-depth interviews with 18 nurses and careworkers who had experience of providing, supervising or assessment of continence care in any long-term aged care facility in Australia. Occupational exposure to incontinence contributes to the low occupational status of carework in long-term aged care facilities, and continence care is a symbolic marker for inequalities within the facility, the nursing profession and society at large. Careworkers' affective and behavioural responses are characterised by: (1) accommodating the context; (2) dissociating oneself; (3) distancing oneself and (4) attempting to elevate one's role status. The theory extends current understandings about the links between incontinence, continence care, courtesy stigma, emotional labour and the low occupational status of carework in long-term aged care facilities. This study provides insights into the ways in which tacit beliefs and values about incontinence, cleanliness and contamination may affect the social organisation and delivery of care in long-term aged care facilities. Nurse leaders should challenge the stigma and devaluation of carework and careworkers, and reframe carework as 'dignity work'. © 2016 John Wiley & Sons Ltd.
Bødtker, Gunhild; Thorstenson, Tore; Lillebø, Bente-Lise P; Thorbjørnsen, Bente E; Ulvøen, Rikke Helen; Sunde, Egil; Torsvik, Terje
2008-12-01
Biogenic production of hydrogen sulphide (H(2)S) is a problem for the oil industry as it leads to corrosion and reservoir souring. Continuous injection of a low nitrate concentration (0.25-0.33 mM) replaced glutaraldehyde as corrosion and souring control at the Veslefrikk and Gullfaks oil field (North Sea) in 1999. The response to nitrate treatment was a rapid reduction in number and activity of sulphate-reducing bacteria (SRB) in the water injection system biofilm at both fields. The present long-term study shows that SRB activity has remained low at < or =0.3 and < or =0.9 microg H(2)S/cm(2)/day at Veslefrikk and Gullfaks respectively, during the 7-8 years with continuous nitrate injection. At Veslefrikk, 16S rRNA gene based community analysis by PCR-DGGE showed that bacteria affiliated to nitrate-reducing sulphide-oxidizing Sulfurimonas (NR-SOB) formed major populations at the injection well head throughout the treatment period. Downstream of deaerator the presence of Sulfurimonas like bacteria was less pronounced, and were no longer observed 40 months into the treatment period. The biofilm community during nitrate treatment was highly diverse and relative stable for long periods of time. At the Gullfaks field, a reduction in corrosion of up to 40% was observed after switch to nitrate treatment. The present study show that nitrate injection may provide a stable long-term inhibition of SRB in sea water injection systems, and that corrosion may be significantly reduced when compared to traditional biocide treatment.
Effect of zero magnetic field on cardiovascular system and microcirculation
NASA Astrophysics Data System (ADS)
Gurfinkel, Yu. I.; At'kov, O. Yu.; Vasin, A. L.; Breus, T. K.; Sasonko, M. L.; Pishchalnikov, R. Yu.
2016-02-01
The effects of zero magnetic field conditions on cardiovascular system of healthy adults have been studied. In order to generate zero magnetic field, the facility for magnetic fields modeling ;ARFA; has been used. Parameters of the capillary blood flow, blood pressure, and the electrocardiogram (ECG) monitoring were measured during the study. All subjects were tested twice: in zero magnetic field and, for comparison, in sham condition. The obtained results during 60 minutes of zero magnetic field exposure demonstrate a clear effect on cardiovascular system and microcirculation. The results of our experiments can be used in studies of long-term stay in hypo-magnetic conditions during interplanetary missions.
Kim, Hyun-Bum; Kwon, Byeong-Jae; Cho, Hyun-Ji; Kim, Ji-Won; Chon, Jeong-Woo; Do, Moon-Ho; Park, Sang-Yong; Kim, Sun-Yeou; Maeng, Sung-Ho; Park, Yoo-Kyoung
2015-01-01
Artemisia princeps (AP) is a flowering perennial used as a traditional medicine and dietary supplement across East Asia. No study has yet assessed its effects on synaptic plasticity in hippocampus and much less in a model of ovarian hormone deficiency. We examined the influence of chronic oral AP ethanol extract treatment in ovariectomized rats on the induction of long-term depression in a representative synapse (CA3-CA1) of the hippocampus. Ovariectomized rats demonstrated lower trabecular mean bone mineral densities than sham, validating the establishment of pathology. Against this background of pathology, AP-treated ovariectomized rats exhibited attenuated long-term depression (LTD) in CA1 relative to water-treated controls as measured by increased field excitatory post-synaptic potentials (fEPSP) activation averages over the post-stimulation period. While pathological significance of long-term depression (LTD) in ovariectomized rats is conflicting, that AP treatment significantly affected its induction offers justification for further study of its influences on plasticity and its related disorders. PMID:25792871
2015-01-01
Traditional chelator-based radio-labeled nanoparticles and positron emission tomography (PET) imaging are playing vital roles in the field of nano-oncology. However, their long-term in vivo integrity and potential mismatch of the biodistribution patterns between nanoparticles and radio-isotopes are two major concerns for this approach. Here, we present a chelator-free zirconium-89 (89Zr, t1/2 = 78.4 h) labeling of mesoporous silica nanoparticle (MSN) with significantly enhanced in vivo long-term (>20 days) stability. Successful radio-labeling and in vivo stability are demonstrated to be highly dependent on both the concentration and location of deprotonated silanol groups (−Si–O–) from two types of silica nanoparticles investigated. This work reports 89Zr-labeled MSN with a detailed labeling mechanism investigation and long-term stability study. With its attractive radio-stability and the simplicity of chelator-free radio-labeling, 89Zr-MSN offers a novel, simple, and accurate way for studying the in vivo long-term fate and PET image-guided drug delivery of MSN in the near future. PMID:26213260
Chen, Feng; Goel, Shreya; Valdovinos, Hector F; Luo, Haiming; Hernandez, Reinier; Barnhart, Todd E; Cai, Weibo
2015-08-25
Traditional chelator-based radio-labeled nanoparticles and positron emission tomography (PET) imaging are playing vital roles in the field of nano-oncology. However, their long-term in vivo integrity and potential mismatch of the biodistribution patterns between nanoparticles and radio-isotopes are two major concerns for this approach. Here, we present a chelator-free zirconium-89 ((89)Zr, t1/2 = 78.4 h) labeling of mesoporous silica nanoparticle (MSN) with significantly enhanced in vivo long-term (>20 days) stability. Successful radio-labeling and in vivo stability are demonstrated to be highly dependent on both the concentration and location of deprotonated silanol groups (-Si-O(-)) from two types of silica nanoparticles investigated. This work reports (89)Zr-labeled MSN with a detailed labeling mechanism investigation and long-term stability study. With its attractive radio-stability and the simplicity of chelator-free radio-labeling, (89)Zr-MSN offers a novel, simple, and accurate way for studying the in vivo long-term fate and PET image-guided drug delivery of MSN in the near future.
Visser, Lennart; Schoonenboom, Judith; Korthagen, Fred A J
2017-01-01
This study reports on the effect of a newly developed 4-week strengths-based training approach to overcome academic procrastination, given to first-year elementary teacher education students ( N = 54). The training was based on a strengths-based approach, in which elements of the cognitive behavioral approach were also used. The purpose of the training was to promote awareness of the personal strengths of students who experience academic procrastination regularly and to teach them how to use their personal strengths in situations in which they usually tend to procrastinate. With a pretest-posttest control group design (two experimental groups: n = 31, control group: n = 23), the effect of the training on academic procrastination was studied after 1, 11, and 24 weeks. Results of a one-way analysis of covariance revealed a significant short-term effect of the training. In the long term (after 11 and 24 weeks), the scores for academic procrastination for the intervention groups remained stable, whereas the scores for academic procrastination for the control group decreased to the same level as those of the intervention groups. The findings of this study suggest that a strengths-based approach can be helpful to students at an early stage of their academic studies to initiate their individual process of dealing with academic procrastination. The findings for the long term show the importance of measuring the outcomes of an intervention not only shortly after the intervention but also in the long term. Further research is needed to find out how the short-term effect can be maintained in the long-term.
Long-Term benefits of stabilizing soil subgrades.
DOT National Transportation Integrated Search
2002-06-01
The main intent of this study was an attempt to address questions concerning bearing strengths, longevity, durability, structural credit, economics, and performance of pavements resting on soil subgrades mixed with chemical admixtures. In-depth field...
Rebirth of the Bashful ballerina
NASA Astrophysics Data System (ADS)
Mursula, Kalevi; Virtanen, Ilpo
2016-04-01
Heliospheric current sheet (HCS) is the continuation of the coronal magnetic equator into space, dividing the heliospheric magnetic field (HMF) into two sectors. Because of its wavy structure, the HCS is also called the ballerina skirt. Several recent studies have proven that the HCS is southward shifted during about three years in the solar declining to minimum phase. This persistent phenomenon, now called the Bashful ballerina, has been seen in geomagnetic indices since 1930s, OMNI data since 1960s, WSO data since mid-1970s and in Ulysses probe measurements during the fast latitude scans in 1994-1995 and 2007. Here we study the long-term evolution of photospheric and coronal magnetic fields and the heliospheric current sheet since 1975 using synoptic maps from six observatories (WSO, MWO, Kitt Peak, SOLIS, SOHO/MDI and SDO/HMI). All data sets depict a fairly similar long-term evolution of magnetic fields and the heliospheric current sheet, and agree on the southward shift of the heliospheric current sheet during all the five included cycles. We show that during solar cycles 20 -- 22, the southward shift of the HCS is due to the axial quadrupole term, reflecting the stronger magnetic field intensity at the southern pole during these times. During cycle 23 the asymmetry is less persistent and due to higher harmonics than the quadrupole term. Currently, in the early declining phase of cycle 24, the HCS is also shifted southward and is, again, due to the axial quadrupole, repeating the pattern of most previous cycles.
Bashful ballerina: Multi-instrument verification and recent behaviour
NASA Astrophysics Data System (ADS)
Mursula, Kalevi; Virtanen, Ilpo
2016-07-01
Heliospheric current sheet (HCS) is the continuation of the coronal magnetic equator into space, dividing the heliospheric magnetic field (HMF) into two sectors. Because of its wavy structure, the HCS is also called the ballerina skirt. Several recent studies have proven that the HCS is southward shifted during about three years in the solar declining to minimum phase. This persistent phenomenon, now called the Bashful ballerina, has been seen in geomagnetic indices since 1930s, OMNI data since 1960s, WSO data since mid-1970s and in Ulysses probe measurements during the fast latitude scans in 1994-1995 and 2007. Here we study the long-term evolution of photospheric and coronal magnetic fields and the heliospheric current sheet since 1975 using synoptic maps from six observatories (WSO, MWO, Kitt Peak, SOLIS, SOHO/MDI and SDO/HMI). All data sets depict a fairly similar long-term evolution of magnetic fields and the heliospheric current sheet, and agree on the southward shift of the heliospheric current sheet during all the five included cycles. We show that during solar cycles 20 -- 22, the southward shift of the HCS is due to the axial quadrupole term, reflecting the stronger magnetic field intensity at the southern pole during these times. During cycle 23 the asymmetry is less persistent and due to higher harmonics than the quadrupole term. Currently, in the early declining phase of cycle 24, the HCS is also shifted southward and is, again, due to the axial quadrupole, repeating the pattern of most previous cycles.
Time Sensitive Termination: Prompt Global Strike in the War on Terror
2009-10-25
field both near and long term solutions to the problem of rapidly destroying fleeting targets halfway around the world when forces are not forward...endeavors to field the near term capability not later than 2015, with an initial fielding objective potentially as early as 2012. 5 The program will...patrolling ballistic missile submarines, the CSM took center stage in the effort to field a near -term solution to the problem. The CSM weapon system
Hirata, Riki; Togashi, Hiroko; Matsumoto, Machiko; Yamaguchi, Taku; Izumi, Takeshi; Yoshioka, Mitsuhiro
2008-08-21
Several lines of evidence have shown that exposure to stress impairs long-term potentiation (LTP) in the CA1 field of the hippocampus, but the detailed mechanisms for this effect remain to be clarified. The present study elucidated the synaptic mechanism of stress-induced LTP suppression in conscious, freely moving rats using electrophysiological approaches. Open field stress (i.e., novel environment stress) and elevated platform stress (i.e., uncontrollable stress) were employed. Basal synaptic transmission was significantly reduced during exposure to elevated platform stress but not during exposure to open field stress. LTP induction was blocked by elevated platform stress but not influenced by open field stress. Significant increases in serum corticosterone levels were observed in the elevated platform stress group compared with the open field stress group. Furthermore, LTP suppression induced by elevated platform stress was prevented by pretreatment with an anxiolytic drug diazepam (1 mg/kg, i.p.). These results suggest that stress-induced LTP suppression depends on the relative intensity of the stressor. The inhibitory synaptic response induced by an intense psychological stress, such as elevated platform stress, may be attributable to LTP impairment in the CA1 field of the hippocampus.
Long-term oceanographic observations in Massachusetts Bay, 1989-2006
Butman, Bradford; Alexander, P. Soupy; Bothner, Michael H.; Borden, Jonathan; Casso, Michael A.; Gutierrez, Benjamin T.; Hastings, Mary E.; Lightsom, Frances L.; Martini, Marinna A.; Montgomery, Ellyn T.; Rendigs, Richard R.; Strahle, William S.
2009-01-01
This data report presents long-term oceanographic observations made in western Massachusetts Bay at long-term site A (LT-A) (42 deg 22.6' N., 70 deg 47.0' W.; nominal water depth 32 meters) from December 1989 through February 2006 and long-term site B (LT-B) (42 deg 9.8' N., 70 deg 38.4' W.; nominal water depth 22 meters) from October 1997 through February 2004 (fig. 1). The observations were collected as part of a U.S. Geological Survey (USGS) study designed to understand the transport and long-term fate of sediments and associated contaminants in Massachusetts Bay. The observations include time-series measurements of current, temperature, salinity, light transmission, pressure, oxygen, fluorescence, and sediment-trapping rate. About 160 separate mooring or tripod deployments were made on about 90 research cruises to collect these long-term observations. This report presents a description of the 16-year field program and the instrumentation used to make the measurements, an overview of the data set, more than 2,500 pages of statistics and plots that summarize the data, and the digital data in Network Common Data Form (NetCDF) format. This research was conducted by the USGS in cooperation with the Massachusetts Water Resources Authority and the U.S. Coast Guard.
Sensitivity Analysis Tailored to Constrain 21st Century Terrestrial Carbon-Uptake
NASA Astrophysics Data System (ADS)
Muller, S. J.; Gerber, S.
2013-12-01
The long-term fate of terrestrial carbon (C) in response to climate change remains a dominant source of uncertainty in Earth-system model projections. Increasing atmospheric CO2 could be mitigated by long-term net uptake of C, through processes such as increased plant productivity due to "CO2-fertilization". Conversely, atmospheric conditions could be exacerbated by long-term net release of C, through processes such as increased decomposition due to higher temperatures. This balance is an important area of study, and a major source of uncertainty in long-term (>year 2050) projections of planetary response to climate change. We present results from an innovative application of sensitivity analysis to LM3V, a dynamic global vegetation model (DGVM), intended to identify observed/observable variables that are useful for constraining long-term projections of C-uptake. We analyzed the sensitivity of cumulative C-uptake by 2100, as modeled by LM3V in response to IPCC AR4 scenario climate data (1860-2100), to perturbations in over 50 model parameters. We concurrently analyzed the sensitivity of over 100 observable model variables, during the extant record period (1970-2010), to the same parameter changes. By correlating the sensitivities of observable variables with the sensitivity of long-term C-uptake we identified model calibration variables that would also constrain long-term C-uptake projections. LM3V employs a coupled carbon-nitrogen cycle to account for N-limitation, and we find that N-related variables have an important role to play in constraining long-term C-uptake. This work has implications for prioritizing field campaigns to collect global data that can help reduce uncertainties in the long-term land-atmosphere C-balance. Though results of this study are specific to LM3V, the processes that characterize this model are not completely divorced from other DGVMs (or reality), and our approach provides valuable insights into how data can be leveraged to be better constrain projections for the land carbon sink.
Fluoroquinolone-resistant Escherichia coli carriage in long-term care facility.
Maslow, Joel N; Lee, Betsy; Lautenbach, Ebbing
2005-06-01
We conducted a cross-sectional study to determine the prevalence of, and risk factors for, colonization with fluoroquinolone (FQ)-resistant Escherichia coli in residents in a long-term care facility. FQ-resistant E. coli were identified from rectal swabs for 25 (51%) of 49 participants at study entry. On multivariable analyses, prior FQ use was the only independent risk factor for FQ-resistant E. coli carriage and was consistent for FQ exposures in the previous 3, 6, 9, or 12 months. Pulsed-field gel electrophoresis of FQ-resistant E. coli identified clonal spread of 1 strain among 16 residents. Loss (6 residents) or acquisition (7 residents) of FQ-resistant E. coli was documented and was associated with de novo colonization with genetically distinct strains. Unlike the case in the hospital setting, FQ-resistant E. coli carriage in long-term care facilities is associated with clonal spread.
Fluoroquinolone-resistant Escherichia coli Carriage in Long-Term Care Facility
Lee, Betsy; Lautenbach, Ebbing
2005-01-01
We conducted a cross-sectional study to determine the prevalence of, and risk factors for, colonization with fluoroquinolone (FQ)-resistant Escherichia coli in residents in a long-term care facility. FQ-resistant E. coli were identified from rectal swabs for 25 (51%) of 49 participants at study entry. On multivariable analyses, prior FQ use was the only independent risk factor for FQ-resistant E. coli carriage and was consistent for FQ exposures in the previous 3, 6, 9, or 12 months. Pulsed-field gel electrophoresis of FQ-resistant E. coli identified clonal spread of 1 strain among 16 residents. Loss (6 residents) or acquisition (7 residents) of FQ-resistant E. coli was documented and was associated with de novo colonization with genetically distinct strains. Unlike the case in the hospital setting, FQ-resistant E. coli carriage in long-term care facilities is associated with clonal spread. PMID:15963284
OXYGEN TRANSFER STUDIES AT THE MADISON METROPOLITAN SEWERAGE DISTRICT FACILITIES
Field studies at the Madison Metropolitan Sewerage District facilities were conducted over a 3-year period to obtain long-term data on the performance of fine pore aeration equipment in municipal wastewater. The studies were conducted on several basins in the East Plant containi...
NASA Technical Reports Server (NTRS)
Swedberg, J. L.; Maschhogg, R. H.
1982-01-01
Characterization studies were performed on flight spare ERB wide field of view Earth flux sensors. Field of view sensitivity profiles were determined for total energy sensors with and without painted baffles. Similarly, sensors with filter domes were also characterized in terms of field of view. The transient response of sensors with filter domes was determined for both long wave and short wave radiation. Long wave radiation interacts directly with the quartz dome causing undesired responses. While short wave radiation was shown not to interact with the domes, modules as a whole exhibited a secondary response to bursts of short wave radiation indicative of a heating mechanism. How the results of this characterization can or should be applied to the data emanating from these sensors on ERB-6 and 7 is outlined.
Elmas, Onur; Comlekci, Selcuk; Koylu, Halis
2012-01-01
ABSTRACT The heart is a contractile organ that can generate its own rhythm. The contraction, or the rhythm, of the heart may be influenced by electromagnetic field (EMF) exposure, because of the heart's excitability characteristic. In previous studies, different methods have been used to study the possible effects of an extremely low frequency electromagnetic field (ELF-EMF) on the heart. But the studies' designs were not similar, and the results were also different. Recent studies have shown some evidence that short-term EMF exposure can influence the heart more than long-term exposure. This study investigated how the heart is affected in the first EMF exposure. In a simulation of the daily exposure of humans to a power frequency, Wistar albino rats were used. By utilizing the Helmholtz-coil set, we obtained a 50-Hz, 1-μT EMF and examined rat heart activity during short-term EMF exposure. No effect was observed under this exposure condition. The results obtained do not confirm a possible mechanism in the electrical activity of the rat heart model.
Design and Field Test of a WSN Platform Prototype for Long-Term Environmental Monitoring
Lazarescu, Mihai T.
2015-01-01
Long-term wildfire monitoring using distributed in situ temperature sensors is an accurate, yet demanding environmental monitoring application, which requires long-life, low-maintenance, low-cost sensors and a simple, fast, error-proof deployment procedure. We present in this paper the most important design considerations and optimizations of all elements of a low-cost WSN platform prototype for long-term, low-maintenance pervasive wildfire monitoring, its preparation for a nearly three-month field test, the analysis of the causes of failure during the test and the lessons learned for platform improvement. The main components of the total cost of the platform (nodes, deployment and maintenance) are carefully analyzed and optimized for this application. The gateways are designed to operate with resources that are generally used for sensor nodes, while the requirements and cost of the sensor nodes are significantly lower. We define and test in simulation and in the field experiment a simple, but effective communication protocol for this application. It helps to lower the cost of the nodes and field deployment procedure, while extending the theoretical lifetime of the sensor nodes to over 16 years on a single 1 Ah lithium battery. PMID:25912349
NASA Astrophysics Data System (ADS)
Batrudinov, Timur M.; Ambarov, Alexander V.; Elfimova, Ekaterina A.; Zverev, Vladimir S.; Ivanov, Alexey O.
2017-06-01
The dynamic magnetic response of ferrofluid in a static uniform external magnetic field to a weak, linear polarized, alternating magnetic field is investigated theoretically. The ferrofluid is modeled as a system of dipolar hard spheres, suspended in a long cylindrical tube whose long axis is parallel to the direction of the static and alternating magnetic fields. The theory is based on the Fokker-Planck-Brown equation formulated for the case when the both static and alternating magnetic fields are applied. The solution of the Fokker-Planck-Brown equation describing the orientational probability density of a randomly chosen dipolar particle is expressed as a series in terms of the spherical Legendre polynomials. The obtained analytical expression connecting three neighboring coefficients of the series makes possible to determine the probability density with any order of accuracy in terms of Legendre polynomials. The analytical formula for the probability density truncated at the first Legendre polynomial is evaluated and used for the calculation of the magnetization and dynamic susceptibility spectra. In the absence of the static magnetic field the presented theory gives the correct single-particle Debye-theory result, which is the exact solution of the Fokker-Planck-Brown equation for the case of applied weak alternating magnetic field. The influence of the static magnetic field on the dynamic susceptibility is analyzed in terms of the low-frequency behavior of the real part and the position of the peak in the imaginary part.
Huang, Shucai; Zhang, Zhixue; Dai, Yuanyuan; Zhang, Changcun; Yang, Cheng; Fan, Lidan; Liu, Jun; Hao, Wei; Chen, Hongxian
2018-01-01
Studies utilizing functional magnetic resonance imaging (fMRI) cue-reactivity paradigms have demonstrated that short-term abstinent or current methamphetamine (MA) users have increased brain activity in the ventral striatum, caudate nucleus and medial frontal cortex, when exposed to MA-related visual cues. However, patterns of brain activity following cue-reactivity in subjects with long-term MA abstinence, especially long-term compulsory drug rehabilitation, have not been well studied. To enrich knowledge in this field, functional brain imaging was conducted during a cue-reactivity paradigm task in 28 individuals with MA use disorder following long-term compulsory drug rehabilitation, and 27 healthy control subjects. The results showed that, when compared with controls, individuals with MA use disorder displayed elevated activity in the bilateral medial prefrontal cortex (mPFC) and right lateral posterior cingulate cortex in response to MA-related images. Additionally, the anterior cingulate region of mPFC activation during the MA-related cue-reactivity paradigm was positively correlated with craving alterations and previous frequency of drug use. No significant differences in brain activity in response to pornographic images were found between the two groups. Compared to MA cues, individuals with MA use disorder had increased activation in the occipital lobe when exposed to pornographic cues. In conclusion, the present study indicates that, even after long-term drug rehabilitation, individuals with MA use disorder have unique brain activity when exposed to MA-related cues. Additionally, our results illustrate that the libido brain response might be restored, and that sexual demand might be more robust than drug demand, in individuals with MA use disorder following long-term drug rehabilitation. PMID:29725310
Huang, Shucai; Zhang, Zhixue; Dai, Yuanyuan; Zhang, Changcun; Yang, Cheng; Fan, Lidan; Liu, Jun; Hao, Wei; Chen, Hongxian
2018-01-01
Studies utilizing functional magnetic resonance imaging (fMRI) cue-reactivity paradigms have demonstrated that short-term abstinent or current methamphetamine (MA) users have increased brain activity in the ventral striatum, caudate nucleus and medial frontal cortex, when exposed to MA-related visual cues. However, patterns of brain activity following cue-reactivity in subjects with long-term MA abstinence, especially long-term compulsory drug rehabilitation, have not been well studied. To enrich knowledge in this field, functional brain imaging was conducted during a cue-reactivity paradigm task in 28 individuals with MA use disorder following long-term compulsory drug rehabilitation, and 27 healthy control subjects. The results showed that, when compared with controls, individuals with MA use disorder displayed elevated activity in the bilateral medial prefrontal cortex (mPFC) and right lateral posterior cingulate cortex in response to MA-related images. Additionally, the anterior cingulate region of mPFC activation during the MA-related cue-reactivity paradigm was positively correlated with craving alterations and previous frequency of drug use. No significant differences in brain activity in response to pornographic images were found between the two groups. Compared to MA cues, individuals with MA use disorder had increased activation in the occipital lobe when exposed to pornographic cues. In conclusion, the present study indicates that, even after long-term drug rehabilitation, individuals with MA use disorder have unique brain activity when exposed to MA-related cues. Additionally, our results illustrate that the libido brain response might be restored, and that sexual demand might be more robust than drug demand, in individuals with MA use disorder following long-term drug rehabilitation.
Finnie, John W; Cai, Zhao; Manavis, Jim; Helps, Stephen; Blumbergs, Peter C
2010-02-01
To determine whether acute or long-term exposure of the brain to mobile telephone radiofrequency (RF) fields produces activation of microglia, which normally respond rapidly to any change in their microenvironment. Using a purpose designed exposure system at 900 MHz, mice were given a single, far-field whole body exposure at a specific absorption rate (SAR) of 4 W/kg for 60 min (acute) or on five successive days per week for 104 weeks (long-term). Control mice were sham-exposed or freely mobile in a cage to control for any stress caused by immobilisation in the exposure module. Positive control brains subjected to a stab wound were also included to confirm the ability of microglia to react to any neural stress. Brains were perfusion-fixed with 4% paraformaldehyde and representative regions of the cerebral cortex and hippocampus immunostained for ionised calcium binding adaptor molecule (Iba1), a specific microglial marker. There was no increase in microglial Iba1 expression in brains short or long-term exposed to mobile telephony microwaves compared to control (sham-exposed or freely moving caged mice) brains, while substantial microglial activation occurred in damaged positive control neural tissue. Acute (60 minutes) or longer duration (2 years) exposure of murine brains to mobile telephone RF fields did not produce any microglial activation detectable by Iba1 immunostaining.
Revisiting hydraulic hysteresis based on long-term monitoring of hydraulic states in lysimeters
NASA Astrophysics Data System (ADS)
Hannes, M.; Wollschläger, U.; Wöhling, T.; Vogel, H.-J.
2016-05-01
Hysteretic processes have been recognized for decades as an important characteristic of soil hydraulic behavior. Several studies confirmed that wetting and drying periods cannot be described by a simple functional relationship, and that some nonequilibrium of the water retention characteristics has to be taken into account. A large number of models describing the hysteresis of the soil water retention characteristic were successfully tested on soil cores under controlled laboratory conditions. However, its relevance under field conditions under natural forcings has rarely been investigated. In practice, the modeling of field soils usually neglects the hysteretic nature of soil hydraulic properties. In this study, long-term observations of water content and matric potential in lysimeters of the lysimeter network TERENO-SoilCan are presented, clearly demonstrating the hysteretic behavior of field soils. We propose a classification into three categories related to different time scales. Based on synthetic and long-term monitoring data, three different models of hysteresis were applied to data sets showing different degrees of hysteresis. We found no single model to be superior to the others. The model ranking depended on the degree of hysteresis. All models were able to reflect the general structure of hysteresis in most cases but failed to reproduce the detailed trajectories of state variables especially under highly transient conditions. As an important result we found that the temporal dynamics of wetting and drying significantly affects these trajectories which should be accounted for in future model concepts.
Human Behaviour in Long-Term Missions
NASA Technical Reports Server (NTRS)
1997-01-01
In this session, Session WP1, the discussion focuses on the following topics: Psychological Support for International Space Station Mission; Psycho-social Training for Man in Space; Study of the Physiological Adaptation of the Crew During A 135-Day Space Simulation; Interpersonal Relationships in Space Simulation, The Long-Term Bed Rest in Head-Down Tilt Position; Psychological Adaptation in Groups of Varying Sizes and Environments; Deviance Among Expeditioners, Defining the Off-Nominal Act in Space and Polar Field Analogs; Getting Effective Sleep in the Space-Station Environment; Human Sleep and Circadian Rhythms are Altered During Spaceflight; and Methodological Approach to Study of Cosmonauts Errors and Its Instrumental Support.
Improving long-term care provision: towards demand-based care by means of modularity
2010-01-01
Background As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Methods Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Results Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. Conclusion The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further enable demand-based provision of long-term care by means of modularity. PMID:20858256
Improving long-term care provision: towards demand-based care by means of modularity.
de Blok, Carolien; Luijkx, Katrien; Meijboom, Bert; Schols, Jos
2010-09-21
As in most fields of health care, societal and political changes encourage suppliers of long-term care to put their clients at the center of care and service provision and become more responsive towards client needs and requirements. However, the diverse, multiple and dynamic nature of demand for long-term care complicates the movement towards demand-based care provision. This paper aims to advance long-term care practice and, to that end, examines the application of modularity. This concept is recognized in a wide range of product and service settings for its ability to design demand-based products and processes. Starting from the basic dimensions of modularity, we use qualitative research to explore the use and application of modularity principles in the current working practices and processes of four organizations in the field of long-term care for the elderly. In-depth semi-structured interviews were conducted with 38 key informants and triangulated with document research and observation. Data was analyzed thematically by means of coding and subsequent exploration of patterns. Data analysis was facilitated by qualitative analysis software. Our data suggest that a modular setup of supply is employed in the arrangement of care and service supply and assists providers of long-term care in providing their clients with choice options and variation. In addition, modularization of the needs assessment and package specification process allows the case organizations to manage client involvement but still provide customized packages of care and services. The adequate setup of an organization's supply and its specification phase activities are indispensible for long-term care providers who aim to do better in terms of quality and efficiency. Moreover, long-term care providers could benefit from joint provision of care and services by means of modular working teams. Based upon our findings, we are able to elaborate on how to further enable demand-based provision of long-term care by means of modularity.
Solubility trapping in formation water as dominant CO(2) sink in natural gas fields.
Gilfillan, Stuart M V; Lollar, Barbara Sherwood; Holland, Greg; Blagburn, Dave; Stevens, Scott; Schoell, Martin; Cassidy, Martin; Ding, Zhenju; Zhou, Zheng; Lacrampe-Couloume, Georges; Ballentine, Chris J
2009-04-02
Injecting CO(2) into deep geological strata is proposed as a safe and economically favourable means of storing CO(2) captured from industrial point sources. It is difficult, however, to assess the long-term consequences of CO(2) flooding in the subsurface from decadal observations of existing disposal sites. Both the site design and long-term safety modelling critically depend on how and where CO(2) will be stored in the site over its lifetime. Within a geological storage site, the injected CO(2) can dissolve in solution or precipitate as carbonate minerals. Here we identify and quantify the principal mechanism of CO(2) fluid phase removal in nine natural gas fields in North America, China and Europe, using noble gas and carbon isotope tracers. The natural gas fields investigated in our study are dominated by a CO(2) phase and provide a natural analogue for assessing the geological storage of anthropogenic CO(2) over millennial timescales. We find that in seven gas fields with siliciclastic or carbonate-dominated reservoir lithologies, dissolution in formation water at a pH of 5-5.8 is the sole major sink for CO(2). In two fields with siliciclastic reservoir lithologies, some CO(2) loss through precipitation as carbonate minerals cannot be ruled out, but can account for a maximum of 18 per cent of the loss of emplaced CO(2). In view of our findings that geological mineral fixation is a minor CO(2) trapping mechanism in natural gas fields, we suggest that long-term anthropogenic CO(2) storage models in similar geological systems should focus on the potential mobility of CO(2) dissolved in water.
Cui, Yanyan; Gong, Dongwei; Yang, Bo; Chen, Hua; Tu, Ming-Hsiang; Zhang, Chaonan; Li, Huan; Liang, Naiwen; Jiang, Liping; Chang, Polun
2018-01-01
Comprehensive Geriatric Assessments (CGAs) have been recommended to be used for better monitoring the health status of elder residents and providing quality care. This study reported how our nurses perceived the usability of CGA component of a mobile integrated-care long term care support system developed in China. We used the Continuity Assessment Record and Evaluation (CARE), developed in the US, as the core CGA component of our Android-based support system, in which apps were designed for all key stakeholders for delivering quality long term care. A convenience sample of 18 subjects from local long term care facilities in Shanghai, China were invited to assess the CGA assessment component in terms of Technology Acceptance Model for Mobile based on real field trial assessment. All (100%) were satisfied with the mobile CGA component. 88.9% perceived the system was easy to learn and use. 99.4% showed their willingness to use for their work. We concluded it is technically feasible to implement a CGA-based mobile integrated care support system in China.
ADVANCING THE FIELD EVALUATIONS AND APPLICATIONS OF LANDFILL BIOREACTORS
The US Environmental Protection Agency (EPA) is undertaking a long-term program to conduct field evaluations of landfill bioreactors. The near-term effort is focused on the development of appropriate monitoring strategies to ensure adequate control of the landfill bioreactors an...
Albuquerque, Kevin; Patel, Mona; Liotta, Margaret; Harkenrider, Matthew; Guo, Rong; Small, William; Ronald, Potkul
2016-05-01
This study aimed to report on long-term effectiveness of involved field radiation therapy (IFRT) in the salvage of localized recurrent ovarian cancer (ROC). A retrospective analysis of 27 patients with a diagnosis of epithelial ovarian cancer who received tumor volume-directed IFRT for localized extraperitoneal recurrences (either as consolidation after cytoreductive surgery (CRS) or as attempted salvage if unresectable) forms the basis of this report. All patients were heavily pretreated with multiple chemotherapy regimens. Involved field radiation therapy was primarily with external beam (median dose, 50.4 Gy). Local recurrence-free survival (LRFS) was defined as freedom from in-field recurrences and was considered as a measure of effectiveness of radiotherapy. Statistical analyses evaluated association between disease-free survival, overall survival, LRFS, and various prognostic factors. Comparison was also made with a similar but unmatched cohort with localized recurrences salvaged by additional chemotherapy instead of local therapies (NIFRT group). Of 27 patients, 17 had optimal CRS before RT. The actuarial survival at 5 and 10 years (in parenthesis) from date of radiation were LRFS (70% and 60%), overall survival (30% and 19%), and disease-free survival (33% and 20%). None of the NIFRT patients survived beyond 5 years from initiation of salvage chemotherapy. Long-term follow-up in this selected series confirmed the benefit of IFRT (±CRS) in localized ROC. Chemotherapy salvage in a similar NIFRT group was not equivalent, suggesting a role for locoregional therapies in selected patients with ROC.
Coors, Anja; Edwards, Mark; Lorenz, Pascale; Römbke, Jörg; Schmelz, Rüdiger M; Topp, Edward; Waszak, Karolina; Wilkes, Graham; Lapen, David R
2016-08-15
Biosolids have well-documented crop and soil benefits similar to other sources of organic amendment, but there is environmental concern due to biosolids-associated pollutants. The present study investigated two field sites that had received biosolids at commercial-scale rates in parallel to associated field sections which were managed similarly but without receiving biosolids (controls). The investigated endpoints were abundance and diversity of soil organisms (nematodes, enchytraeids and earthworms) and soil fauna feeding activity as measured by the bait lamina assay. Repeated sampling of one of the field sites following the only biosolids application demonstrated an enrichment effect typical for organic amendments, which was mostly exhausted after 44months. After an initial suppression, the proportion of free-living plant-parasitic nematodes tended to increase in the biosolids-amended soil over time. Yet, none of the endpoints at this site indicated significant negative effects resulting from the biosolids until 44months post application. In contrast to the repeatedly tilled first field site, the second one was left fallow after three biosolids applications, and was sampled 96months post last application. It was only at this field site that potential evidence for a long-term impact of biosolids was detected with regard to two endpoints: earthworm abundance and structure of the nematode assemblage. Agricultural management and correlation with abiotic soil parameters explained the observed difference in earthworm abundance. Yet, the development of a highly structured and mature nematode assemblage at the control but not at the biosolids-amended section of this fallow field could not be explained by such correlations nor by soil metal concentrations. Overall, the present study found only weak evidence for negative long-term impacts of biosolids applied at commercial rates on soil fauna. High-level community parameters such as the nematode structure index (SI) appeared more suitable to detect deleterious effects on soil fauna than simple abundance measurements. Copyright © 2016 Elsevier B.V. All rights reserved.
Long-term mobile phone use and the risk of vestibular schwannoma: a Danish nationwide cohort study.
Schüz, Joachim; Steding-Jessen, Marianne; Hansen, Søren; Stangerup, Sven-Eric; Cayé-Thomasen, Per; Poulsen, Aslak Harbo; Olsen, Jørgen H; Johansen, Christoffer
2011-08-15
Vestibular schwannomas grow in the region within the brain where most of the energy by radiofrequency electromagnetic fields from using mobile phones is absorbed. The authors used 2 Danish nationwide cohort studies, one a study of all adult Danes subscribing for a mobile phone in 1995 or earlier and one on sociodemographic factors and cancer risk, and followed subjects included in both cohorts for occurrence of vestibular schwannoma up to 2006 inclusively. In this study including 2.9 million subjects, a long-term mobile phone subscription of ≥11 years was not related to an increased vestibular schwannoma risk in men (relative risk estimate = 0.87, 95% confidence interval: 0.52, 1.46), and no vestibular schwannoma cases among long-term subscribers occurred in women versus 1.6 expected. Vestibular schwannomas did not occur more often on the right side of the head, although the majority of Danes reported holding their mobile phone to the right ear. Vestibular schwannomas in long-term male subscribers were not of larger size than expected. Overall, no evidence was found that mobile phone use is related to the risk of vestibular schwannoma. Because of the usually slow growth of vestibular schwannoma and possible diagnostic delay, further surveillance is indicated.
[Benefits and risks of growth hormone in adults with growth hormone deficiency].
Díez, Juan J; Cordido, Fernando
2014-10-21
Adult growth hormone (GH) deficiency is a well-recognized clinical syndrome with adverse health consequences. Many of these may improve after replacement therapy with recombinant GH. This treatment induces an increase in lean body mass and a decrease in fat mass. In long-term studies, bone mineral density increases and muscle strength improves. Health-related quality of life tends to increase after treatment with GH. Lipid profile and markers of cardiovascular risk also improve with therapy. Nevertheless, GH replacement therapy is not without risk. According to some studies, GH increases blood glucose, body mass index and waist circumference and may promote long-term development of diabetes and metabolic syndrome. Risk of neoplasia does not appear to be increased in adults treated with GH, but there are some high-risk subgroups. Methodological shortcomings and difficulties inherent to long-term studies prevent definitive conclusions about the relationship between GH and survival. Therefore, research in this field should remain active. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.
Interaction of Electromagnetic Fields with Biosynthetic Processes in Connective Tissue Cells
1989-12-01
Normal Chondrocytes.............................................10 Swarm Rat Chondrosarcoma Cells..................................15 Conclusions...articular cartilage, and in rat chondrosarcoma cells (a continuous cell line). Another long-term goal is to study the possible role of fields in...Investigators have recently found that bovine [12, 13, 14], rabbit [15], and human [161 chondrocytes as well as Swarm rat chondrosarcoma cells [171 isolated a
Cai, Andong; Xu, Hu; Shao, Xingfang; Zhu, Ping; Zhang, Wenju; Xu, Minggang; Murphy, Daniel V
2016-01-01
Long-term manure application is recognized as an efficient management practice to enhance soil organic carbon (SOC) accumulation and nitrogen (N) mineralization capacity. A field study was established in 1979 to understand the impact of long-term manure and/or chemical fertilizer application on soil fertility in a continuous maize cropping system. Soil samples were collected from field plots in 2012 from 9 fertilization treatments (M0CK, M0N, M0NPK, M30CK, M30N, M30NPK, M60CK, M60N, and M60NPK) where M0, M30, and M60 refer to manure applied at rates of 0, 30, and 60 t ha(-1) yr(-1), respectively; CK indicates no fertilizer; N and NPK refer to chemical fertilizer in the forms of either N or N plus phosphorus (P) and potassium (K). Soils were separated into three particle-size fractions (2000-250, 250-53, and <53 μm) by dry- and wet-sieving. A laboratory incubation study of these separated particle-size fractions was used to evaluate the effect of long-term manure, in combination with/without chemical fertilization application, on the accumulation and mineralization of SOC and total N in each fraction. Results showed that long-term manure application significantly increased SOC and total N content and enhanced C and N mineralization in the three particle-size fractions. The content of SOC and total N followed the order 2000-250 μm > 250-53 μm > 53 μm fraction, whereas the amount of C and N mineralization followed the reverse order. In the <53 μm fraction, the M60NPK treatment significantly increased the amount of C and N mineralized (7.0 and 10.1 times, respectively) compared to the M0CK treatment. Long-term manure application, especially when combined with chemical fertilizers, resulted in increased soil microbial biomass C and N, and a decreased microbial metabolic quotient. Consequently, long-term manure fertilization was beneficial to both soil C and N turnover and microbial activity, and had significant effect on the microbial metabolic quotient.
The octapolic ellipsoidal term in magnetoencephalography
NASA Astrophysics Data System (ADS)
Dassios, George; Hadjiloizi, Demetra; Kariotou, Fotini
2009-01-01
The forward problem of magnetoencephalography (MEG) in ellipsoidal geometry has been studied by Dassios and Kariotou ["Magnetoencephalography in ellipsoidal geometry," J. Math. Phys. 44, 220 (2003)] using the theory of ellipsoidal harmonics. In fact, the analytic solution of the quadrupolic term for the magnetic induction field has been calculated in the case of a dipolar neuronal current. Nevertheless, since the quadrupolic term is only the leading nonvanishing term in the multipole expansion of the magnetic field, it contains not enough information for the construction of an effective algorithm to solve the inverse MEG problem, i.e., to recover the position and the orientation of a dipole from measurements of the magnetic field outside the head. For this task, the next multipole of the magnetic field is also needed. The present work provides exactly this octapolic contribution of the dipolar current to the expansion of the magnetic induction field. The octapolic term is expressed in terms of the ellipsoidal harmonics of the third degree, and therefore it provides the highest order terms that can be expressed in closed form using long but reasonable analytic and algebraic manipulations. In principle, the knowledge of the quadrupolic and the octapolic terms is enough to solve the inverse problem of identifying a dipole inside an ellipsoid. Nevertheless, a simple inversion algorithm for this problem is not yet known.
Visser, Lennart; Schoonenboom, Judith; Korthagen, Fred A. J.
2017-01-01
This study reports on the effect of a newly developed 4-week strengths-based training approach to overcome academic procrastination, given to first-year elementary teacher education students (N = 54). The training was based on a strengths-based approach, in which elements of the cognitive behavioral approach were also used. The purpose of the training was to promote awareness of the personal strengths of students who experience academic procrastination regularly and to teach them how to use their personal strengths in situations in which they usually tend to procrastinate. With a pretest-posttest control group design (two experimental groups: n = 31, control group: n = 23), the effect of the training on academic procrastination was studied after 1, 11, and 24 weeks. Results of a one-way analysis of covariance revealed a significant short-term effect of the training. In the long term (after 11 and 24 weeks), the scores for academic procrastination for the intervention groups remained stable, whereas the scores for academic procrastination for the control group decreased to the same level as those of the intervention groups. The findings of this study suggest that a strengths-based approach can be helpful to students at an early stage of their academic studies to initiate their individual process of dealing with academic procrastination. The findings for the long term show the importance of measuring the outcomes of an intervention not only shortly after the intervention but also in the long term. Further research is needed to find out how the short-term effect can be maintained in the long-term. PMID:29163317
A Long-term study of three rotating radio transients
NASA Astrophysics Data System (ADS)
Bhattacharyya, B.; Lyne, A. G.; Stappers, B. W.; Weltevrede, P.; Keane, E. F.; McLaughlin, M. A.; Kramer, M.; Jordan, C.; Bassa, C.
2018-04-01
We present the longest-term timing study so far of three Rotating Radio Transients (RRATs) - J1819-1458, J1840-1419 and J1913+1330 - performed using the Lovell, Parkes and Green Bank telescopes over the past decade. We study long-term and short-term variations of the pulse emission rate from these RRATs and report a marginal indication of a long-term increase in pulse detection rate over time for PSR J1819-1458 and J1913+1330. For PSR J1913+1330, we also observe a two orders of magnitude variation in the observed pulse detection rates across individual epochs, which may constrain the models explaining the origin of RRAT pulses. PSR J1913+1330 is also observed to exhibit a weak persistent emission mode. We investigate the post-glitch timing properties of J1819-1458 (the only RRAT for which glitches are observed) and discuss the implications for possible glitch models. Its post-glitch over-recovery of the frequency derivative is magnetar-like and similar behaviour is only observed for two other pulsars, both of which have relatively high magnetic field strengths. Following the over-recovery we also observe that some fraction of the pre-glitch frequency derivative is gradually recovered.
NASA Astrophysics Data System (ADS)
Sawada, Masataka; Nishimoto, Soshi; Okada, Tetsuji
2017-01-01
In high-level radioactive waste disposal repositories, there are long-term complex thermal, hydraulic, and mechanical (T-H-M) phenomena that involve the generation of heat from the waste, the infiltration of ground water, and swelling of the bentonite buffer. The ability to model such coupled phenomena is of particular importance to the repository design and assessments of its safety. We have developed a T-H-M-coupled analysis program that evaluates the long-term behavior around the repository (called "near-field"). We have also conducted centrifugal model tests that model the long-term T-H-M-coupled behavior in the near-field. In this study, we conduct H-M-coupled numerical simulations of the centrifugal near-field model tests. We compare numerical results with each other and with results obtained from the centrifugal model tests. From the comparison, we deduce that: (1) in the numerical simulation, water infiltration in the rock mass was in agreement with the experimental observation. (2) The constant-stress boundary condition in the centrifugal model tests may cause a larger expansion of the rock mass than in the in situ condition, but the mechanical boundary condition did not affect the buffer behavior in the deposition hole. (3) The numerical simulation broadly reproduced the measured bentonite pressure and the overpack displacement, but did not reproduce the decreasing trend of the bentonite pressure after 100 equivalent years. This indicates the effect of the time-dependent characteristics of the surrounding rock mass. Further investigations are needed to determine the effect of initial heterogeneity in the deposition hole and the time-dependent behavior of the surrounding rock mass.
Manned space flight in transition
NASA Technical Reports Server (NTRS)
Drucker, E. E.; Pooler, W. S.; Wilemon, D. L.; Wood, B. D.
1973-01-01
A study was conducted to analyze the reorientation of NASA programs in the post-Apollo period. The study is an external view of NASA by unbiased observers as an input to and aid in the decision making process concerning near and long term planning. The subjects discussed are: (1) the near-term NASA scenario; (2) organization of field centers; (3) planning activities; and (4) operational activities. A summary of the recommendations arising as a result of the study is presented.
CAISI Operational Assessment (OA) data collection results. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1997-01-31
One of the lessons learned from Operation Desert Shield/Storm was the inability of deployed Combat Service Support (CSS) computers to exchange data effectively in a battlefield environment. The work-around solution to this previously identified problem has been to physically carry floppy disks between computers. A General Officer Steering Committee, directed by the Vice Chief of Staff of the Army, determined that immediate corrective action was necessary to ensure viability of the CSS Battlefield Mission Area. The study recommended that a three-phased system development plan address short-, mid- and long-term CSS automation communication interface requirements. In response to this study, Programmore » Executive Office (PEO) Standard Army Management Information System (STAMIS) authorized the development of the CSS Automated Information System Interface (CAISI). Phase I (Near-Term) equipped the {open_quotes}first to fight{close_quotes} Contingency Corps units. Phase II (Mid-Term) is being fielded to the remainder of Force Package One units in the active force. Phase III (Long-Term) will equip the remaining units. CAISI is now in the early stages of Phase II fielding. Prior to full Phase II fielding, CAISI must be approved for production by a Milestone III decision authority. Part of the data that will be used in the Milestone III decision is a demonstration of the CAISI`s operational suitability, as assessed by the US Army Operational Test and Evaluation Command (OPTEC). This assessment will be performed through an Operational Assessment (OA) using data provided from previous technical testing, such as the CAISI Customer User Test (CUT), and a field training exercise conducted by units of the XVIII Airborne Corps. The field training exercise data collection took place during two events.« less
Knowledge outcomes within rotational models of social work field education.
Birkenmaier, Julie; Curley, Jami; Rowan, Noell L
2012-01-01
This study assessed knowledge outcomes among concurrent, concurrent/sequential, and sequential rotation models of field instruction. Posttest knowledge scores of students ( n = 231) in aging-related field education were higher for students who participated in the concurrent rotation model, and for those who completed field education at a long-term care facility. Scores were also higher for students in programs that infused a higher number of geriatric competencies in their curriculum. Recommendations are provided to programs considering rotation models of field education related to older adults.
Reed, C C; Fan, C; Koutlas, N T; Shaheen, N J; Dellon, E S
2017-11-01
Limited data describe the long-term efficacy of dietary elimination in eosinophilic oesophagitis (EoE). To assess the long-term outcomes of food elimination diets for treatment of adults with EoE. We conducted a retrospective cohort study at our centre analysing all EoE patients receiving a food elimination diet without concomitant steroids. Baseline data were abstracted using standardised collection forms. Follow-up data from a mean 24.9-month period were collected for patients with a histological response to a food elimination diet during and after food reintroduction. The main outcomes were symptomatic, endoscopic and histological responses. Of 52 patients, 18 received a 6-food food elimination diet, 32 received targeted diet, and two received a 6-food food elimination diet with targeted elimination. There were 21 (40%) patients with an initial histological response. Responders reported less dysphagia after treatment (95% baseline vs 11%; P = .001) and at the end of follow-up (95% baseline vs 33%; P = .008). Significant and durable endoscopic improvements were recorded at the same time points: Endoscopic reference score: 3.2 vs 0.7; P = .001; and 3.2 vs 1.7; P = .06. Histological findings improved after the most restrictive diet in responders (49.8 vs 4.1 eosinophils per high-power field; P = .001) and remained suppressed in the 10 initial responders maintaining compliance at the end of follow-up (5.2 eosinophils per high-power field). Among EoE patients responding to a food elimination diet and remaining adherent, maintenance dietary therapy produced durable long-term symptomatic, endoscopic and histological disease control. These long-term data confirm that a food elimination diet is an effective maintenance treatment option in select adults with EoE. © 2017 John Wiley & Sons Ltd.
NASA Technical Reports Server (NTRS)
1982-01-01
Evaluating of the combined utility of narrowband and multispectral imaging in both the infrared and visible for the lithologic identification of geologic materials, and of the combined utility of multispectral imaging in the visible and infrared for lithologic mapping on a global bases are near term recommendations for future imaging capabilities. Long term recommendations include laboratory research into methods of field sampling and theoretical models of microscale mixing. The utility of improved spatial and spectral resolutions and radiometric sensitivity is also suggested for the long term. Geobotanical remote sensing research should be conducted to (1) separate geological and botanical spectral signatures in individual picture elements; (2) study geobotanical correlations that more fully simulate natural conditions; and use test sites designed to test specific geobotanical hypotheses.
Long-Term Hydrologic Impacts of Controlled Drainage Using DRAINMOD
NASA Astrophysics Data System (ADS)
Saadat, S.; Bowling, L. C.; Frankenberger, J.
2017-12-01
Controlled drainage is a management strategy designed to mitigate water quality issues caused by subsurface drainage but it may increase surface ponding and runoff. To improve controlled drainage system management, a long-term and broader study is needed that goes beyond the experimental studies. Therefore, the goal of this study was to parametrize the DRAINMOD field-scale, hydrologic model for the Davis Purdue Agricultural Center located in Eastern Indiana and to predict the subsurface drain flow and surface runoff and ponding at this research site. The Green-Ampt equation was used to characterize the infiltration, and digital elevation models (DEMs) were used to estimate the maximum depressional storage as the surface ponding parameter inputs to DRAINMOD. Hydraulic conductivity was estimated using the Hooghoudt equation and the measured drain flow and water table depths. Other model inputs were either estimated or taken from the measurements. The DRAINMOD model was calibrated and validated by comparing model predictions of subsurface drainage and water table depths with field observations from 2012 to 2016. Simulations based on the DRAINMOD model can increase understanding of the environmental and hydrological effects over a broader temporal and spatial scale than is possible using field-scale data and this is useful for developing management recommendations for water resources at field and watershed scales.
“Studying Injured Minds” – The Vietnam Head Injury Study and 40 Years of Brain Injury Research
Raymont, Vanessa; Salazar, Andres M.; Krueger, Frank; Grafman, Jordan
2011-01-01
The study of those who have sustained traumatic brain injuries (TBI) during military conflicts has greatly facilitated research in the fields of neuropsychology, neurosurgery, psychiatry, neurology, and neuroimaging. The Vietnam Head Injury Study (VHIS) is a prospective, long-term follow-up study of a cohort of 1,221 Vietnam veterans with mostly penetrating brain injuries, which has stretched over more than 40 years. The scope of this study, both in terms of the types of injury and fields of examination, has been extremely broad. It has been instrumental in extending the field of TBI research and in exposing pressing medical and social issues that affect those who suffer such injuries. This review summarizes the history of conflict-related TBI research and the VHIS to date, as well as the vast range of important findings the VHIS has established. PMID:21625624
Long-Term Research in Ecology and Evolution (LTREE): 2015 survey data.
Bradford, Mark A; Leiserowitz, Anthony; Feinberg, Geoffrey; Rosenthal, Seth A; Lau, Jennifer A
2017-11-01
To systematically assess views on contributions and future activities for long-term research in ecology and evolution (LTREE), we conducted and here provide data responses and associated metadata for a survey of ecological and evolutionary scientists. The survey objectives were to: (1) Identify and prioritize research questions that are important to address through long-term, ecological field experiments; and (2) understand the role that these experiments might play in generating and applying ecological and evolutionary knowledge. The survey was developed adhering to the standards of the American Association for Public Opinion Research. It was administered online using Qualtrics Survey Software. Survey creation was a multi-step process, with questions and format developed and then revised with, for example, input from an external advisory committee comprising senior and junior ecological and evolutionary researchers. The final questionnaire was released to ~100 colleagues to ensure functionality and then fielded 2 d later (January 7 th , 2015). Two professional societies distributed it to their membership, including the Ecological Society of America, and it was posted to three list serves. The questionnaire was available through February 8th 2015 and completed by 1,179 respondents. The distribution approach targeted practicing ecologists and evolutionary biologists in the U.S. Quantitative (both ordinal and categorical) closed-ended questions used a predefined set of response categories, facilitating direct comparison across all respondents. Qualitative, open-ended questions, provided respondents the opportunity to develop their own answers. We employed quantitative questions to score views on the extent to which long-term experimental research has contributed to understanding in ecology and evolutionary biology; its role compared to other approaches (e.g., short-term experiments); justifications for and caveats to long-term experiments; and the relative importance of incentives for conducting long-term research. Qualitative questions were used to assess community views on the most important topics and questions for long-term research to address, and primary incentives and challenges to realizing this work. Finally, demographic data were collected to determine if views were conditional on such things as years of experience and field of expertise. The final questionnaire and all responses are provided for unrestricted use. © 2017 by the Ecological Society of America.
Estimating future flood frequency and magnitude in basins affected by glacier wastage.
DOT National Transportation Integrated Search
2015-03-01
We present field measurements of meteorology, hydrology and glaciers and long-term modeled projections of glacier mass balance and : stream flow informed by downscaled climate simulations. The study basins include Valdez Glacier Stream (342 km2 : ), ...
Kocur, Chris M D; Lomheim, Line; Molenda, Olivia; Weber, Kela P; Austrins, Leanne M; Sleep, Brent E; Boparai, Hardiljeet K; Edwards, Elizabeth A; O'Carroll, Denis M
2016-07-19
Nanoscale zerovalent iron (nZVI) is an emerging technology for the remediation of contaminated sites. However, there are concerns related to the impact of nZVI on in situ microbial communities. In this study, the microbial community composition at a contaminated site was monitored over two years following the injection of nZVI stabilized with carboxymethyl cellulose (nZVI-CMC). Enhanced dechlorination of chlorinated ethenes to nontoxic ethene was observed long after the expected nZVI oxidation. The abundance of Dehalococcoides (Dhc) and vinyl chloride reductase (vcrA) genes, monitored using qPCR, increased by over an order of magnitude in nZVI-CMC-impacted wells. The entire microbial community was tracked using 16S rRNA gene amplicon pyrosequencing. Following nZVI-CMC injection, a clear shift in microbial community was observed, with most notable increases in the dechlorinating genera Dehalococcoides and Dehalogenimonas. This study suggests that coupled abiotic degradation (i.e., from reaction with nZVI) and biotic degradation fueled by CMC led to the long-term degradation of chlorinated ethenes at this field site. Furthermore, nZVI-CMC addition stimulated dehalogenator growth (e.g., Dehalococcoides) and biotic degradation of chlorinated ethenes.
Lekfeldt, Jonas Duus Stevens; Magid, Jakob; Holm, Peter E; Nybroe, Ole; Brandt, Kristian Koefoed
2014-11-01
Copper (Cu) is known to accumulate in agricultural soils receiving urban waste products as fertilizers. We here report the use of the leucine incorporation technique to determine pollution-induced community tolerance (Leu-PICT) to Cu in a long-term agricultural field trial. A significantly increased bacterial community tolerance to Cu was observed for soils amended with organic waste fertilizers and was positively correlated with total soil Cu. However, metal speciation and whole-cell bacterial biosensor analysis demonstrated that the observed PICT responses could be explained entirely by Cu speciation and bioavailability artifacts during Leu-PICT detection. Hence, the agricultural application of urban wastes (sewage sludge or composted municipal waste) simulating more than 100 years of use did not result in sufficient accumulation of Cu to select for Cu resistance. Our findings also have implications for previously published PICT field studies and demonstrate that stringent PICT detection criteria are needed for field identification of specific toxicants. Copyright © 2014 Elsevier Ltd. All rights reserved.
Manipulation of long-term dynamics in a colloidal active matter system using speckle light fields
NASA Astrophysics Data System (ADS)
Pince, Ercag; Velu, Sabareesh K. P.; Callegari, Agnese; Elahi, Parviz; Gigan, Sylvain; Volpe, Giovanni; Volpe, Giorgio
Particles undergoing a stochastic motion within a disordered medium is a ubiquitous physical and biological phenomena. Examples can be given from organelles performing tasks in the cytoplasm to large animals moving in patchy environment. Here, we use speckle light fields to study the anomalous diffusion in an active matter system consisting of micron-sized silica particles(diameter 5 μm) and motile bacterial cells (E. coli). The speckle light fields are generated by mode mixing inside a multimode optical fiber where a small amount of incident laser power is needed to obtain an effective disordered optical landscape for the purpose of optical manipulation. We experimentally show how complex potentials contribute to the long-term dynamics of the active matter system and observed an enhanced diffusion of particles interacting with the active bacterial bath in the speckle light fields. We showed that this effect can be tuned and controlled by varying the intensity and the statistical properties of the speckle pattern. Potentially, these results could be of interest for many technological applications, such as the manipulation of microparticles inside optically disordered media of biological interest.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gaspar, L.E.; Dawson, D.J.; Tilley-Gulliford, S.A.
1991-09-01
Thirty-two patients with posterior fossa medulloblastoma underwent treatment with electron irradiation to the spinal field. The 5- and 10-year actuarial survival rates were 57% and 50%, respectively. Late complications observed in the 15 patients followed up for more than 5 years were short stature (six patients), decreased sitting-standing height ratio (four patients), scoliosis (two patients), poor school performance (seven patients), xerostomia (one patient), esophageal stricture (one patient), pituitary dysfunction (four patients), primary hypothyroidism (one patient), bilateral eighth-nerve deafness (one patient), and carcinoma of the thyroid (one patient). Complications following treatment with electrons to a spinal field are compared with reportedmore » complications following treatment with photons to the spinal field. Although short-term reactions were minimal, the authors found no difference in late complications. More sophisticated treatment planning may show such a long-term benefit in the future.« less
Prediction of field emitter cathode lifetime based on measurement of I- V curves
NASA Astrophysics Data System (ADS)
Bormashov, V. S.; Nikolski, K. N.; Baturin, A. S.; Sheshin, E. P.
2003-06-01
A technique is presented, which allows the prediction of field emitter cathode lifetime without long-term direct measurements of cathode parameters stability. This technique is based on periodic measurements of cathode I- V characteristics. Moreover, it allows performing a post-experiment optimization for the appropriate choice of the feedback system to provide a stable operation during a long time. The proposed technique was applied to study the emission properties of reticulated vitreous carbon (RVC) and thermo-enlarged graphite (TEG). For the given cathodes, the characteristic time of the cathode destruction was estimated.
Yang, Bin-Juan; Huang, Guo-Qin; Xu, Ning; Wang, Shu-Bin
2013-09-01
Based on a long term field experiment, this paper studied the effects of different multiple cropping systems on the weed community composition and species diversity under paddy-upland rotation. The multiple cropping rotation systems could significantly decrease weed density and inhibited weed growth. Among the rotation systems, the milk vetch-early rice-late maize --> milk vetchearly maize intercropped with early soybean-late rice (CCSR) had the lowest weed species dominance, which inhibited the dominant weeds and decreased their damage. Under different multiple cropping systems, the main weed community was all composed of Monochoia vaginalis, Echinochloa crusgalli, and Sagittaria pygmae, and the similarity of weed community was higher, with the highest similarity appeared in milk vetch-early rice-late maize intercropped with late soybean --> milk vetch-early maize-late rice (CSCR) and in CCSR. In sum, the multiple cropping rotations in paddy field could inhibit weeds to a certain extent, but attentions should be paid to the damage of some less important weeds.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perrin, Tess E.; Davis, Robert G.; Wilkerson, Andrea M.
This GATEWAY project evaluated four field installations to better understand the long-term performance of a number of LED products, which can hopefully stimulate improvements in designing, manufacturing, specifying, procuring, and installing LED products. Field studies provide the opportunity to discover and investigate issues that cannot be simulated or uncovered in a laboratory, but the installed performance over time of commercially available LED products has not been well documented. Improving long-term performance can provide both direct energy savings by reducing the need to over-light to account for light loss and indirect energy savings through better market penetration due to SSL’s competitivemore » advantages over less-efficient light source technologies. The projects evaluated for this report illustrate that SSL use is often motivated by advantages other than energy savings, including maintenance savings, easier integration with control systems, and improved lighting quality.« less
NASA Astrophysics Data System (ADS)
Isaacson, Sivan; Blumberg, Dan G.; Ginat, Hanan; Shalmon, Benny
2013-04-01
Vegetation in hyper arid zones is very sparse as is. Monitoring vegetation changes in hyper arid zones is important because any reduction in the vegetation cover in these areas can lead to a considerable reduction in the carrying capacity of the ecological system. This study focuses on the impact of climate fluctuations on the acacia population in the southern Arava valley, Israel. The period of this survey includes a sequence of dry years with no flashfloods in most of the plots that ended in two years with vast floods. Arid zone acacia trees play a significant role in the desert ecosystem by moderating the extreme environmental conditions including radiation, temperature, humidity and precipitation. The trees also provide nutrients for the desert dwellers. Therefore, acacia trees in arid zones are considered to be `keystone species', because they have major influence over both plants and animal species, i.e., biodiversity. Long term monitoring of the acacia tree population in this area can provide insights into long term impacts of climate fluctuations on ecosystems in arid zones. Since 2000, a continuous yearly based survey on the three species of acacia population in seven different plots is conducted in the southern Arava (established by Shalmon, ecologist of the Israel nature and parks authority). The seven plots representing different ecosystems and hydrological regimes. A yearly based population monitoring enabled us to determine the mortality and recruitment rate of the acacia populations as well as growing rates of individual trees. This survey provides a unique database of the acacia population dynamics during a sequence of dry years that ended in a vast flood event during the winter of 2010. A lack of quantitative, nondestructive methods to estimate and monitor stress status of the acacia trees, led us to integrate remote sensing tools (ground and air-based) along with conventional field measurements in order to develop a long term monitoring of acacia trees in hyper arid zones. This study includes further work on the development of ground based remote sensing as a new tool to monitor stress indicators as part of long term ecological research. Since acacia trees are long lived, we were able to identify individual trees in satellite images from 1968 (corona) and expand our monitoring "into the past". Remote sensing expands the spatial and temporal database and is thus a powerful tool for long term monitoring in arid zones, where access is limited and long-term ground data are rare.
Armaş, Iuliana; Mendes, Diana A.; Popa, Răzvan-Gabriel; Gheorghe, Mihaela; Popovici, Diana
2017-01-01
The aim of this exploratory research is to capture spatial evolution patterns in the Bucharest metropolitan area using sets of single polarised synthetic aperture radar (SAR) satellite data and multi-temporal radar interferometry. Three sets of SAR data acquired during the years 1992–2010 from ERS-1/-2 and ENVISAT, and 2011–2014 from TerraSAR-X satellites were used in conjunction with the Small Baseline Subset (SBAS) and persistent scatterers (PS) high-resolution multi-temporal interferometry (InSAR) techniques to provide maps of line-of-sight displacements. The satellite-based remote sensing results were combined with results derived from classical methodologies (i.e., diachronic cartography) and field research to study possible trends in developments over former clay pits, landfill excavation sites, and industrial parks. The ground displacement trend patterns were analysed using several linear and nonlinear models, and techniques. Trends based on the estimated ground displacement are characterised by long-term memory, indicated by low noise Hurst exponents, which in the long-term form interesting attractors. We hypothesize these attractors to be tectonic stress fields generated by transpressional movements. PMID:28252103
Armaş, Iuliana; Mendes, Diana A; Popa, Răzvan-Gabriel; Gheorghe, Mihaela; Popovici, Diana
2017-03-02
The aim of this exploratory research is to capture spatial evolution patterns in the Bucharest metropolitan area using sets of single polarised synthetic aperture radar (SAR) satellite data and multi-temporal radar interferometry. Three sets of SAR data acquired during the years 1992-2010 from ERS-1/-2 and ENVISAT, and 2011-2014 from TerraSAR-X satellites were used in conjunction with the Small Baseline Subset (SBAS) and persistent scatterers (PS) high-resolution multi-temporal interferometry (InSAR) techniques to provide maps of line-of-sight displacements. The satellite-based remote sensing results were combined with results derived from classical methodologies (i.e., diachronic cartography) and field research to study possible trends in developments over former clay pits, landfill excavation sites, and industrial parks. The ground displacement trend patterns were analysed using several linear and nonlinear models, and techniques. Trends based on the estimated ground displacement are characterised by long-term memory, indicated by low noise Hurst exponents, which in the long-term form interesting attractors. We hypothesize these attractors to be tectonic stress fields generated by transpressional movements.
Design and Application of a Field Sensing System for Ground Anchors in Slopes
Choi, Se Woon; Lee, Jihoon; Kim, Jong Moon; Park, Hyo Seon
2013-01-01
In a ground anchor system, cables or tendons connected to a bearing plate are used for stabilization of slopes. Then, the stability of a slope is dependent on maintaining the tension levels in the cables. So far, no research on a strain-based field sensing system for ground anchors has been reported. Therefore, in this study, a practical monitoring system for long-term sensing of tension levels in tendons for anchor-reinforced slopes is proposed. The system for anchor-reinforced slopes is composed of: (1) load cells based on vibrating wire strain gauges (VWSGs), (2) wireless sensor nodes which receive and process the signals from load cells and then transmit the result to a master node through local area communication, (3) master nodes which transmit the data sent from sensor nodes to the server through mobile communication, and (4) a server located at the base station. The system was applied to field sensing of ground anchors in the 62 m-long and 26 m-high slope at the side of the highway. Based on the long-term monitoring, the safety of the anchor-reinforced slope can be secured by the timely applications of re-tensioning processes in tendons. PMID:23507820
Long-term effects of low-dose proton radiation on immunity in mice: shielded vs. unshielded
NASA Technical Reports Server (NTRS)
Pecaut, Michael J.; Gridley, Daila S.; Nelson, Gregory A.
2003-01-01
BACKGROUND: Outside the protection of the terrestrial environment, astronauts on any long-term missions will unavoidably be exposed to fields of charged particle radiation dominated by protons. These fields and their biological risks are modified in complex ways by the presence of protective shielding. METHODS: To examine the long-term effects of space-like proton exposures on immune status, we treated female C57BL/6 mice with 3 or 4 Gy of 250 MeV monoenergetic protons or the complex space-like radiation field produced after 250 MeV protons are transported through 15 g x cm(-2) aluminum shielding. The animals were euthanized 122 d post-irradiation and lymphocyte phenotypes, hematological parameters, and lymphocyte blastogenesis were characterized. RESULTS: There were significant dose-dependent decreases in macrophage, CD3+/CD8+ T, NK, platelet, and red blood cell populations, as well as low hematocrit and hemoglobin levels. In contrast, dose-dependent increases in spontaneous, but not mitogen-induced, blastogenesis were noted. The differences in dose composition between pristine and shielded proton fields did not lead to significant effects in most measures, but did result in significant changes in monocyte and macrophage populations and spontaneous blastogenesis in the spleen. CONCLUSIONS: The data indicate that whole body exposure to proton radiation at doses of the order of large solar particle events or clinical treatment fractions may have long-term effects on immune system status.
NASA Astrophysics Data System (ADS)
Yamazaki, T.; Acton, G.; Channell, J. E.; Palmer, E. C.; Richter, C.; Yamamoto, Y.
2011-12-01
Since the 1960s, possible correlation between geomagnetic field strength and polarity length on 10^6 years or longer time scale has been suggested, and its relation to geodynamo processes has been discussed (e.g., Cox, 1968). Paleointensity estimation using single crystal silicate indicated that the geomagnetic field was stronger during Cretaceous Superchron, when polarity reversal was inhibited in geodynamo (e.g., Tarduno et al., 2001). However, it has not yet been understood well whether such correlation exists when polarity reversals frequently occur. Tauxe and Hartl (1997) suggested a weak correlation using Oligocene sediments (ca 23-34 Ma) from DSDP Site 522. This is the only continuous paleointensity data of these ages published so far. We have conducted a paleomagnetic study of sediment cores of Eocene and Oligocene ages taken at Sites U1331, U1332, and U1333 of IODP Exp. 320/321 "Pacific Equatorial Age Transect (PEAT)". The objective includes better understanding of long-term changes in relative paleointensity and revisiting the issue of intensity-polarity length correlation. Relative paleointensity records from individual sites showed good between-site consistency for variations of 10^4 to 10^5 year time scale, suggesting that geomagnetic field behavior was successfully recovered on these time scales. The results confirmed usefulness of relative paleointensity for high-resolution inter-core correlation, that is, paleointensity assisted chronostratigraphy. On the other hand, long-term changes (ca 10^6 years or longer) in normalized intensity showed obvious anti-correlation with ARM/SIRM, a rock magnetic proxy of magnetic grain size and/or magnetostatic interactions among magnetic grains. The normalized intensity also showed correlation with sedimentation rates. These results indicate lithological contamination to relative paleointensity records. We compare our records with that of Tauxe and Hartl (1997) during Oligocene derived from South Atlantic sediments, which belongs to a different oceanographic regime to the PEAT cores. Although some strong paleointensity intervals are reproduced in our records, overall agreement in long-term changes is not good. Emergence of significant correlation between normalized intensity and ARM/SIRM and/or sedimentation rates is not limited to PEAT cores, but occurs also in sediments of other areas. For reliable estimation of long-term paleointensity changes from sediments, it is imperative to understand physical mechanism of such correlation and develop a method for correction.
Adaptations of the vestibular system to short and long-term exposures to altered gravity
NASA Astrophysics Data System (ADS)
Bruce, L. L.
2003-10-01
Long-term space flight creates unique environmental conditions to which the vestibular system must adapt for optimal survival of a given organism. The development and maintenance of vestibular connections are controlled by environmental gravitational stimulation as well as genetically controlled molecular interactions. This paper describes the effects of hypergravity on axonal growth and dendritic morphology, respectively. Two aspects of this vestibular adaptation are examined: (1) How does long-term exposure to hypergravity affect the development of vestibular axons? (2) How does short-term exposure to extremely rapid changes in gravity, such as those that occur during shuttle launch and landing, affect dendrites of the vestibulocerebellar system? To study the effects of longterm exposures to altered gravity, embryonic rats that developed in hypergravity were compared to microgravity-exposed and control rats. Examination of the vestibular projections from epithelia devoted to linear and angular acceleration revealed that the terminal fields segregate differently in rat embryos that gestated in each of the gravitational environments.To study the effects of short-term exposures to altered gravity, mice were exposed briefly to strong vestibular stimuli and the vestibulocerebellum was examined for any resulting morphological changes. My data show that these stimuli cause intense vestibular excitation of cerebellar Purkinje cells, which induce up-regulation of clathrin-mediated endocytosis and other morphological changes that are comparable to those seen in long-term depression. This system provides a basis for studying how the vestibular environment can modify cerebellar function, allowing animals to adapt to new environments.
NASA Technical Reports Server (NTRS)
Chen, Junye; DelGenio, Anthony D.; Carlson, Barbara e.; Bosilovich, Michael G.
2007-01-01
The dominant interannual El Nino-Southern Oscillation phenomenon (ENSO) and the short length of climate observation records make it difficult to study long-term climate variations in the spatiotemporal domain. Based on the fact that the ENS0 signal spreads to remote regions and induces delayed climate variation through atmospheric teleconnections, we develop an ENSO-removal method through which the ENS0 signal can be approximately removed at the grid box level from the spatiotemporal field of a climate parameter. After this signal is removed, long-term climate variations, namely, the global warming trend (GW) and the Pacific pan-decadal variability (PDV), are isolated at middle and low latitudes in the climate parameter fields from observed and reanalyses datasets. Except for known GW characteristics, the warming that occurs in the Pacific basin (approximately 0.4K in the 2oth century) is much weaker than in surrounding regions and the other two ocean basins (approximately 0.8K). The modest warming in the Pacific basin is likely due to its dynamic nature on the interannual and decadal time scales and/or the leakage of upper ocean water through the Indonesian Throughflow. Based on NCEP/NCAR and ERA-40 reanalyses, a comprehensive atmospheric structure associated with GW is given. Significant discrepancies exist between the two datasets, especially in the tightly coupled dynamic and water vapor fields. The dynamic field based on NCEP/NCAR reanalysis, which shows a change in the Walker Circulation, is consistent with the GW change in the surface temperature field. However, intensification in the Hadley Circulation is associated with GW trend in the ERA-40 reanalysis.
Dunlap, Kent D; Keane, Geoffrey; Ragazzi, Michael; Lasky, Elise; Salazar, Vielka L
2017-07-01
The brain structure of many animals is influenced by their predators, but the cellular processes underlying this brain plasticity are not well understood. Previous studies showed that electric fish ( Brachyhypopomus occidentalis ) naturally exposed to high predator ( Rhamdia quelen ) density and tail injury had reduced brain cell proliferation compared with individuals facing few predators and those with intact tails. However, these field studies described only correlations between predator exposure and cell proliferation. Here, we used a congener Brachyhypopomus gauderio and another electric fish Apteronotus leptorhynchus to experimentally test the hypothesis that exposure to a predator stimulus and tail injury causes alterations in brain cell proliferation. To simulate predator exposure, we either amputated the tail followed by short-term (1 day) or long-term (17-18 days) recovery or repeatedly chased intact fish with a plastic rod over a 7 day period. We measured cell proliferation (PCNA+ cell density) in the telencephalon and diencephalon, and plasma cortisol, which commonly mediates stress-induced changes in brain cell proliferation. In both species, either tail amputation or simulated predator chase decreased cell proliferation in the telencephalon in a manner resembling the effect of predators in the field. In A. leptorhynchus , cell proliferation decreased drastically in the short term after tail amputation and partially rebounded after long-term recovery. In B. gauderio , tail amputation elevated cortisol levels, but repeated chasing had no effect. In A. leptorhynchus , tail amputation elevated cortisol levels in the short term but not in the long term. Thus, predator stimuli can cause reductions in brain cell proliferation, but the role of cortisol is not clear. © 2017. Published by The Company of Biologists Ltd.
Using Natural Experiments to Study the Impact of Media on the Family
ERIC Educational Resources Information Center
Price, Joseph; Dahl, Gordon B.
2012-01-01
The randomized trial is the gold standard in scientific research and is used by several fields to study the effects of media. Although useful for studying the immediate response to media exposure, the experimental approach is not well suited to studying long-term effects or behavior outside the laboratory. The "natural experiment" approach, a…
De La Cueva Bueno, Patricia; Gillerman, Leonid; Gehr, Ronald; Oron, Gideon
2017-03-01
Nanotechnology applications can be used for filtering low quality waters, allowing under given conditions, the removal of salts and other micropollutants from these waters. A long-term field experiment, implementing nanotechnology in the form of UltraFiltration (UF) and Reverse Osmosis (RO) for salt removal from treated wastewater, was conducted with secondary effluents, aiming to prove the sustainability of agricultural production using irrigation with treated wastewater. Six outdoor field treatments, each under four replications, were conducted for examining the salt accumulation effects on the soil and the crops. The field experiments proved that crop development is correlated with the water quality as achieved from the wastewater filtration capability of the hybrid nanotechnology system. The key goal was to maintain sustainable food production, despite the low quality of the waters. Of the six treatment methods tested, irrigation with RO-treated effluent produced the best results in terms of its effect on soil salinity and crop yield. Nevertheless, it must be kept in mind that this process is not only costly, but it also removes all organic matter content from the irrigation water, requiring the addition of fertilizers to the effluent. Copyright © 2016. Published by Elsevier Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pareige, P.; Russell, K.F.; Stoller, R.E.
1998-03-01
Atom probe field ion microscopy (APFIM) investigations of the microstructure of unaged (as-fabricated) and long-term thermally aged ({approximately} 100,000 h at 280 C) surveillance materials from commercial reactor pressure vessel steels were performed. This combination of materials and conditions permitted the investigation of potential thermal-aging effects. This microstructural study focused on the quantification of the compositions of the matrix and carbides. The APFIM results indicate that there was no significant microstructural evolution after a long-term thermal exposure in weld, plate, or forging materials. The matrix depletion of copper that was observed in weld materials was consistent with the copper concentrationmore » in the matrix after the stress-relief heat treatment. The compositions of cementite carbides aged for 100,000 h were compared with the Thermocalc{trademark} prediction. The APFIM comparisons of materials under these conditions are consistent with the measured change in mechanical properties such as the Charpy transition temperature.« less
Temporal variations in the potential hydrological performance of extensive green roof systems
NASA Astrophysics Data System (ADS)
De-Ville, Simon; Menon, Manoj; Stovin, Virginia
2018-03-01
Existing literature provides contradictory information about variation in potential green roof hydrological performance over time. This study has evaluated a long-term hydrological monitoring record from a series of extensive green roof test beds to identify long-term evolutions and sub-annual (seasonal) variations in potential hydrological performance. Monitoring of nine differently-configured extensive green roof test beds took place over a period of 6 years in Sheffield, UK. Long-term evolutions and sub-annual trends in maximum potential retention performance were identified through physical monitoring of substrate field capacity over time. An independent evaluation of temporal variations in detention performance was undertaken through the fitting of reservoir-routing model parameters. Aggregation of the resulting retention and detention variations permitted the prediction of extensive green roof hydrological performance in response to a 1-in-30-year 1-h summer design storm for Sheffield, UK, which facilitated the comparison of multi and sub-annual hydrological performance variations. Sub-annual (seasonal) variation was found to be significantly greater than long-term evolution. Potential retention performance increased by up to 12% after 5-years, whilst the maximum sub-annual variation in potential retention was 27%. For vegetated roof configurations, a 4% long-term improvement was observed for detention performance, compared to a maximum 63% sub-annual variation. Consistent long-term reductions in detention performance were observed in unvegetated roof configurations, with a non-standard expanded-clay substrate experiencing a 45% reduction in peak attenuation over 5-years. Conventional roof configurations exhibit stable long-term hydrological performance, but are nonetheless subject to sub-annual variation.
USDA-ARS?s Scientific Manuscript database
The Long-Term Agroecosystem Research network is building a road map for the sustainable intensification of U.S. agriculture by designing strategies that are locally appropriate and applicable to multiple scales of agricultural organization. The 18 sites in the LTAR network represent a diversity of l...
USDA-ARS?s Scientific Manuscript database
The genetic effects of long term random mating and natural selection aided by genetic male sterility (gms) were evaluated in two soybean [Glycine max (L.) Merr.] populations designated: RSII and RSIII. These populations were evaluated in the field at three locations each with two replications. Genot...
To fully understand the potential long-term ecological impacts a pollutant has on a species, population-level effects must be estimated. Since long-term field experiments are typically not feasible, vital rates such as survival, growth, and reproduction of individual organisms ar...
Long-term impact of a precision agriculture system on grain crop production
USDA-ARS?s Scientific Manuscript database
Research is lacking on the long-term impacts of field-scale precision agriculture practices on grain production. Following more than a decade (1993-2003) of yield and soil mapping and water quality assessment, a multi-faceted, ‘precision agriculture system’ (PAS) was implemented from 2004 to 2014 on...
Emerging technologies for long-term antimicrobial device coatings: advantages and limitations
Cyphert, Erika L
2017-01-01
Over the past 20 years, the field of antimicrobial medical device coatings has expanded nearly 30-fold with technologies shifting their focus from diffusion-only based (short-term antimicrobial eluting) coatings to long-term antimicrobial eluting and intrinsically antimicrobial functioning materials. A variety of emergent coatings have been developed with the goal of achieving long-term antimicrobial activity in order to mitigate the risk of implanted device failure. Specifically, the coatings can be grouped into two categories: those that use antibiotics in conjunction with a polymer coating and those that rely on the intrinsic properties of the material to kill or repel bacteria that come into contact with the surface. This review covers both long-term drug-eluting and non-eluting coatings and evaluates the inherent advantages and disadvantages of each type while providing an overview of variety applications that the coatings have been utilized in. Impact statement This work provides an overview, with advantages and limitations of the most recently developed antibacterial coating technologies, enabling other researchers in the field to more easily determine which technology is most advantageous for them to further develop and pursue. PMID:28110543
Spatial encoding in spinal sensorimotor circuits differs in different wild type mice strains
Thelin, Jonas; Schouenborg, Jens
2008-01-01
Background Previous studies in the rat have shown that the spatial organisation of the receptive fields of nociceptive withdrawal reflex (NWR) system are functionally adapted through experience dependent mechanisms, termed somatosensory imprinting, during postnatal development. Here we wanted to clarify 1) if mice exhibit a similar spatial encoding of sensory input to NWR as previously found in the rat and 2) if mice strains with a poor learning capacity in various behavioural tests, associated with deficient long term potention, also exhibit poor adaptation of NWR. The organisation of the NWR system in two adult wild type mouse strains with normal long term potentiation (LTP) in hippocampus and two adult wild type mouse strains exhibiting deficiencies in corresponding LTP were used and compared to previous results in the rat. Receptive fields of reflexes in single hindlimb muscles were mapped with CO2 laser heat pulses. Results While the spatial organisation of the nociceptive receptive fields in mice with normal LTP were very similar to those in rats, the LTP impaired strains exhibited receptive fields of NWRs with aberrant sensitivity distributions. However, no difference was found in NWR thresholds or onset C-fibre latencies suggesting that the mechanisms determining general reflex sensitivity and somatosensory imprinting are different. Conclusion Our results thus confirm that sensory encoding in mice and rat NWR is similar, provided that mice strains with a good learning capability are studied and raise the possibility that LTP like mechanisms are involved in somatosensory imprinting. PMID:18495020
GPS Imaging of Time-Variable Earthquake Hazard: The Hilton Creek Fault, Long Valley California
NASA Astrophysics Data System (ADS)
Hammond, W. C.; Blewitt, G.
2016-12-01
The Hilton Creek Fault, in Long Valley, California is a down-to-the-east normal fault that bounds the eastern edge of the Sierra Nevada/Great Valley microplate, and lies half inside and half outside the magmatically active caldera. Despite the dense coverage with GPS networks, the rapid and time-variable surface deformation attributable to sporadic magmatic inflation beneath the resurgent dome makes it difficult to use traditional geodetic methods to estimate the slip rate of the fault. While geologic studies identify cumulative offset, constrain timing of past earthquakes, and constrain a Quaternary slip rate to within 1-5 mm/yr, it is not currently possible to use geologic data to evaluate how the potential for slip correlates with transient caldera inflation. To estimate time-variable seismic hazard of the fault we estimate its instantaneous slip rate from GPS data using a new set of algorithms for robust estimation of velocity and strain rate fields and fault slip rates. From the GPS time series, we use the robust MIDAS algorithm to obtain time series of velocity that are highly insensitive to the effects of seasonality, outliers and steps in the data. We then use robust imaging of the velocity field to estimate a gridded time variable velocity field. Then we estimate fault slip rate at each time using a new technique that forms ad-hoc block representations that honor fault geometries, network complexity, connectivity, but does not require labor-intensive drawing of block boundaries. The results are compared to other slip rate estimates that have implications for hazard over different time scales. Time invariant long term seismic hazard is proportional to the long term slip rate accessible from geologic data. Contemporary time-invariant hazard, however, may differ from the long term rate, and is estimated from the geodetic velocity field that has been corrected for the effects of magmatic inflation in the caldera using a published model of a dipping ellipsoidal magma chamber. Contemporary time-variable hazard can be estimated from the time variable slip rate estimated from the evolving GPS velocity field.
Production and Uses of Multi-Decade Geodetic Earth Science Data Records
NASA Astrophysics Data System (ADS)
Bock, Y.; Kedar, S.; Moore, A. W.; Fang, P.; Liu, Z.; Sullivan, A.; Argus, D. F.; Jiang, S.; Marshall, S. T.
2017-12-01
The Solid Earth Science ESDR System (SESES) project funded under the NASA MEaSUREs program produces and disseminates mature, long-term, calibrated and validated, GNSS based Earth Science Data Records (ESDRs) that encompass multiple diverse areas of interest in Earth Science, such as tectonic motion, transient slip and earthquake dynamics, as well as meteorology, climate, and hydrology. The ESDRs now span twenty-five years for the earliest stations and today are available for thousands of global and regional stations. Using a unified metadata database and a combination of GNSS solutions generated by two independent analysis centers, the project currently produces four long-term ESDR's: Geodetic Displacement Time Series: Daily, combined, cleaned and filtered, GIPSY and GAMIT long-term time series of continuous GPS station positions (global and regional) in the latest version of ITRF, automatically updated weekly. Geodetic Velocities: Weekly updated velocity field + velocity field histories in various reference frames; compendium of all model parameters including earthquake catalog, coseismic offsets, and postseismic model parameters (exponential or logarithmic). Troposphere Delay Time Series: Long-term time series of troposphere delay (30-min resolution) at geodetic stations, necessarily estimated during position time series production and automatically updated weekly. Seismogeodetic records for historic earthquakes: High-rate broadband displacement and seismic velocity time series combining 1 Hz GPS displacements and 100 Hz accelerometer data for select large earthquakes and collocated cGPS and seismic instruments from regional networks. We present several recent notable examples of the ESDR's usage: A transient slip study that uses the combined position time series to unravel "tremor-less" slow tectonic transient events. Fault geometry determination from geodetic slip rates. Changes in water resources across California's physiographic provinces at a spatial resolution of 75 km. Retrospective study of a southern California summer monsoon event.
NASA Astrophysics Data System (ADS)
Leon-Perez, M.; Hernandez, W. J.; Armstrong, R.
2016-02-01
Reported cases of seagrass loss have increased over the last 40 years, increasing the awareness of the need for assessing seagrass health. In situ monitoring has been the main method to assess spatial and temporal changes in seagrass ecosystem. Although remote sensing techniques with multispectral imagery have been recently used for these purposes, long-term analysis is limited to the sensor's mission life. The objective of this project is to determine long-term changes in seagrass habitat cover at Caja de Muertos Island Nature Reserve, by combining in situ data with a satellite image and historical aerial photography. A current satellite imagery of the WorldView-2 sensor was used to generate a 2014 benthic habitat map for the study area. The multispectral image was pre-processed using: conversion of digital numbers to radiance, and atmospheric and water column corrections. Object-based image analysis was used to segment the image into polygons representing different benthic habitats and to classify those habitats according to the classification scheme developed for this project. The scheme include the following benthic habitat categories: seagrass (sparse, dense and very dense), colonized hard bottom (sparse, dense and very dense), sand and mix algae on unconsolidated sediments. Field work was used to calibrate the satellite-derived benthic maps and to asses accuracy of the final products. In addition, a time series of satellite imagery and historic aerial photography from 1950 to 2014 provided data to assess long-term changes in seagrass habitat cover within the Reserve. Preliminary results show an increase in seagrass habitat cover, contrasting with the worldwide declining trend. The results of this study will provide valuable information for the conservation and management of seagrass habitat in the Caja de Muertos Island Nature Reserve.
Mondaca, Pedro; Catrin, Joanie; Verdejo, José; Sauvé, Sébastien; Neaman, Alexander
2017-04-01
To better determine phytotoxicity thresholds for metals in the soil, studies should use actual field-contaminated soil samples rather than metal-spiked soil preparations. However, there are surprisingly few such data available for Cu phytotoxicity in field-contaminated soils. Moreover, these studies differ from each other with regards to soil characteristics and experimental setups. This study aimed at more accurately estimating Cu phytotoxicity thresholds using field-collected agricultural soils (Entisols) from areas exposed to contamination from Cu mining. For this purpose, the exposure to Cu was assessed by measuring total soil Cu, soluble Cu, free Cu 2+ activity, and Cu in the plant aerial tissues. On the other hand, two bioassay durations (short-term and long-term), three plant species (Avena sativa L., Brassica rapa CrGC syn. Rbr, and Lolium perenne L.), and five biometric endpoints (shoot length and weight, root length and weight, and number of seed pods) were considered. Overall plant growth was best predicted by total Cu content of the soil. Despite some confounding factors, it was possible to determine EC 10 , EC 25 and EC 50 of total Cu in the soil. Brassica rapa was more sensitive than Avena sativa for all endpoints, while Lolium perenne was of intermediate sensitivity. For the short-term bioassay (21 days for all three species), the averaged EC 10 , EC 25 and EC 50 values of total soil Cu (in mg kg -1 ) were 356, 621, and 904, respectively. For the long-term bioassay (62 days for oat and 42 days for turnip), the averaged EC 10 , EC 25 and EC 50 values of total soil Cu (in mg kg -1 ) were 355, 513, and 688, respectively. The obtained results indicate that chronic test is a suitable method for assessing Cu phytotoxicity in field-contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Baranov, A. A.; Ermak, S. V.; Kulachenkov, N. K.; Petrenko, M. V.; Sagitov, E. A.; Semenov, V. V.
2017-11-01
This paper presents the results of investigation Stark shift effect influence on the long-term stability of a dual scheme of quantum magnetometers. Such scheme allows suppressing Stark shift components when a certain pumping light polarization is applied. As a result, long-term stability of a quantum sensor increases. However, when low-frequency (LF) and microwave fields are attached to a single vapor cell a coherence circulation in hyperfine structure of alkali atoms takes place. Physical origin of this effect is associated with the so called “dressed” atom theory, when atom is “dressed” by LF field. It yields in multiphoton absorption and resonance frequency shift. First estimates for this shift based on density matrix evolution formalism are provided in the paper.
Chronic exposure to ELF fields may induce depression
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, B.W.
Exposure to extremely-low-frequency (ELF) electric or magnetic fields has been postulated as a potentially contributing factor in depression. Epidemiologic studies have yielded positive correlations between magnetic- and/or electric-field strengths in local environments and the incidence of depression-related suicide. Chronic exposure to ELF electric or magnetic fields can disrupt normal circadian rhythms in rat pineal serotonin-N-acetyltransferase activity as well as in serotonin and melatonin concentrations. Such disruptions in the circadian rhythmicity of pineal melatonin secretion have been associated with certain depressive disorders in human beings. In the rat, ELF fields may interfere with tonic aspects of neuronal input to the pinealmore » gland, giving rise to what may be termed functional pinealectomy. If long-term exposure to ELF fields causes pineal dysfunction in human beings as it does in the rat, such dysfunction may contribute to the onset of depression or may exacerbate existing depressive disorders. 85 references.« less
USDA-ARS?s Scientific Manuscript database
This field experiment was conducted in association with a long term tillage study established in fall 2007 at the Judd Hill Foundation Research Farm in Northeast Arkansas to assess agronomic and environmental impacts of conservation tillage systems. In component studies in 2016 we evaluated performa...
AN 11-YEAR FIELD STUDY WITH PASTEURIA PENETRANS: LESSONS LEARNED THE HARD WAY.
USDA-ARS?s Scientific Manuscript database
Beginning in 1998, a bioassay using second-stage juveniles (J2) from a greenhouse (GH) population of the root-knot nematode Meloidogyne arenaria (Ma) was used to monitor endospore densities of the bacterium Pasteuria penetrans, which was parasitizing Ma in a long-term rotation study (begun in 1991)....
USDA-ARS?s Scientific Manuscript database
The endospore-forming bacterium Pasteuria penetrans is an obligate parasite of root-knot nematodes (Meloidogyne spp.). This study was a continuation of earlier research to determine the effect of crop sequence on abundance of the bacterium, and was conducted from 2000 to 2008 at a field site natura...
Li, Shao-Peng; Cadotte, Marc W; Meiners, Scott J; Pu, Zhichao; Fukami, Tadashi; Jiang, Lin
2016-09-01
Whether plant communities in a given region converge towards a particular stable state during succession has long been debated, but rarely tested at a sufficiently long time scale. By analysing a 50-year continuous study of post-agricultural secondary succession in New Jersey, USA, we show that the extent of community convergence varies with the spatial scale and species abundance classes. At the larger field scale, abundance-based dissimilarities among communities decreased over time, indicating convergence of dominant species, whereas incidence-based dissimilarities showed little temporal tend, indicating no sign of convergence. In contrast, plots within each field diverged in both species composition and abundance. Abundance-based successional rates decreased over time, whereas rare species and herbaceous plants showed little change in temporal turnover rates. Initial abandonment conditions only influenced community structure early in succession. Overall, our findings provide strong evidence for scale and abundance dependence of stochastic and deterministic processes over old-field succession. © 2016 John Wiley & Sons Ltd/CNRS.
Soil Organic Matter Dynamics in the Rothamsted Long-term Experiments
NASA Astrophysics Data System (ADS)
MacDonald, A.; Poulton, P.
2009-04-01
Soil science research at Rothamsted dates from 1843 when John Bennet Lawes and Joseph Henry Gilbert started the first of a series of what became long-term field experiments. The main object of these experiments was to examine the effect of inorganic and organic fertilisers and manures on crop yield and soil fertility. These "Classical Field Experiments" included studies on winter wheat (Broadbalk 1843), spring barley (Hoos Barley 1852) and permanent grassland (Park Grass 1856). Additional experiments were established in the 20th century to examine the value of ley-arable cropping, including the Highfield and Fosters Ley-arable experiments (1948) and the Woburn Ley-arable experiment (1938). More recently, the effects of incorporating organic manures and cereal straw have been examined. Early results quickly showed the benefits of inorganic N and P fertilisers on crop production, but the effects of contrasting land uses and management practices on soil properties emerged more slowly. Measurements of soil organic carbon (C) and nitrogen (N) in soils taken at intervals from the long-term experiments indicate that the rate of soil organic matter (SOM) accumulation is controlled largely by the balance between the rate of organic matter inputs and its oxidation rate, and that these are strongly influenced by land use and management, soil texture (especially clay content) and climate. A recent examination of soil organic C data from two long-term grassland experiments in the UK (including Park Grass) indicates that any changes observed in soil organic C under long-term grasslands over the past 40 years are more likely to be due to changes in land use and management rather than climate change. Data from the Rothamsted Long-term experiments have been used to develop and test biogeochemical models of C and N dynamics. In particular, the Roth-C model has successfully simulated soil C dynamics in the long-term experiments at Rothamsted and elsewhere. This model uses several organic matter pools, including decomposable and resistant plant material, soil microbial biomass, humified organic matter and inert organic matter and was one of the 31 models included in the GCTE SOMNET network. The Rothamsted Long-term Experiments together with their archived samples and data have proven especially useful for examining the impact of land use and management on soil organic matter dynamics. They continue to yield important information and are an increasingly valuable experimental resource for today's scientists. Whilst their future long-term uses cannot be predicted, provided they are well maintained, the application of new scientific techniques to examine both fresh and archived samples will continue to provide information of environmental and ecological significance to future generations. Rothamsted Research receives grant-aided support from the Biotechnology and Biological Sciences Research Council and additional support from the Lawes Agricultural Trust. Presentation of this work forms part of the ANAEE EC design study (www.anaee.com).
ERIC Educational Resources Information Center
Fitzgerald, Brian K.; Barkanic, Steve; Cardenas-Navia, Isabel; Elzey, Karen; Hughes, Debbie; Kashiri, Erica; Troyan, Danielle
2014-01-01
Partnerships between higher education and business have long been an important part of the academic landscape, but often they are based on shorter-term transactional objectives rather than on longer-term strategic goals. BHEF's National Higher Education and Workforce Initiative brings together business and academia at the institutional,…
Liu, Chia-Nan; Chen, Rong-Her; Chen, Kuo-Sheng
2006-02-01
The understanding of long-term landfill settlement is important for landfill design and rehabilitation. However, suitable models that can consider both the mechanical and biodecomposition mechanisms in predicting the long-term landfill settlement are generally not available. In this paper, a model based on unsaturated consolidation theory and considering the biodegradation process is introduced to simulate the landfill settlement behaviour. The details of problem formulations and the derivation of the solution for the formulated differential equation of gas pressure are presented. A step-by-step analytical procedure employing this approach for estimating settlement is proposed. The proposed model can generally model the typical features of short-term and long-term behaviour. The proposed model also yields results that are comparable with the field measurements.
Curved Microneedle Array-Based sEMG Electrode for Robust Long-Term Measurements and High Selectivity
Kim, Minjae; Kim, Taewan; Kim, Dong Sung; Chung, Wan Kyun
2015-01-01
Surface electromyography is widely used in many fields to infer human intention. However, conventional electrodes are not appropriate for long-term measurements and are easily influenced by the environment, so the range of applications of sEMG is limited. In this paper, we propose a flexible band-integrated, curved microneedle array electrode for robust long-term measurements, high selectivity, and easy applicability. Signal quality, in terms of long-term usability and sensitivity to perspiration, was investigated. Its motion-discriminating performance was also evaluated. The results show that the proposed electrode is robust to perspiration and can maintain a high-quality measuring ability for over 8 h. The proposed electrode also has high selectivity for motion compared with a commercial wet electrode and dry electrode. PMID:26153773
NASA Astrophysics Data System (ADS)
Lepping, R. P.; Wu, C.-C.; Berdichevsky, D. B.; Szabo, A.
2018-04-01
We give the results of parameter fitting of the magnetic clouds (MCs) observed by the Wind spacecraft for the three-year period 2013 to the end of 2015 (called the "Present" period) using the MC model of Lepping, Jones, and Burlaga ( J. Geophys. Res. 95, 11957, 1990). The Present period is almost coincident with the solar maximum of the sunspot number, which has a broad peak starting in about 2012 and extending to almost 2015. There were 49 MCs identified in the Present period. The modeling gives MC quantities such as size, axial attitude, field handedness, axial magnetic-field strength, center time, and closest-approach vector. Derived quantities are also estimated, such as axial magnetic flux, axial current density, and total axial current. Quality estimates are assigned representing excellent, fair/good, and poor. We provide error estimates on the specific fit parameters for the individual MCs, where the poor cases are excluded. Model-fitting results that are based on the Present period are compared to the results of the full Wind mission from 1995 to the end of 2015 (Long-term period), and compared to the results of two other recent studies that encompassed the periods 2007 - 2009 and 2010 - 2012, inclusive. We see that during the Present period, the MCs are, on average, slightly slower, slightly weaker in axial magnetic field (by 8.7%), and larger in diameter (by 6.5%) than those in the Long-term period. However, in most respects, the MCs in the Present period are significantly closer in characteristics to those of the Long-term period than to those of the two recent three-year periods. However, the rate of occurrence of MCs for the Long-term period is 10.3 year^{-1}, whereas this rate for the Present period is 16.3 year^{-1}, similar to that of the period 2010 - 2012. Hence, the MC occurrence rate has increased appreciably in the last six years. MC Type (N-S, S-N, All N, All S, etc.) is assigned to each MC; there is an inordinately large percentage of All S, by about a factor of two compared to that of the Long-term period, indicating many strongly tipped MCs. In 2005, there was a distinct change in variability and average value (viewed at 1/2 year averages) of the duration, MC speed, axial magnetic field strength, axial magnetic flux, and total current to lower values. In the Present period, upstream shocks occur for 43% of the 49 cases; for comparison, the Long-term rate is 56%.
Ahmadi, Khodabakhsh; Rezazade, Majid; Saadat, Hassan; Kimiaei, Seyed Ali; Zade, Nima Hoseyn
2015-01-01
Aims: In the field of family research, previous studies have made great strides toward understanding the relationship between marital conflict and quality. However, they have only studied couples in short-term marriages. Therefore, much remains to be unraveled with regard to long-term marriages. We aimed investigate the comparative contribution of aspects of marital conflict to marital quality in short-and long-term marriages in Iranian families. Materials and Methods: Using random clustered sampling, 400 dyads in intact first marriages were surveyed across eight provinces of Iran. Complete surveys for both husbands and wives were returned for 162 households (couple's response rate: 40.5%). Survey measures included demographics questionnaire, Barati and Sanai's Marital Conflict Questionnaire and Blum and Mehrabian's Comprehensive Marital Satisfaction Scale. Structural equation modeling was used to test the actor-partner interdependence model of marital conflict-marital quality. Results: Generalized additive models were incorporated to define what constitutes short-and long-term marriages. Based on the models regressed, duration ≤ 10 years was defined as short-term, whereas duration ≥ 25 years was labeled long-term. In short-term marriages (n = 44), decreased sexual relations, increased daily hassles and sidedness in relations with parents were negatively associated with marital quality in both actor and actor-to-partner paths. In long-term married couples (n = 46), only increased daily hassles (P < 0.001) and disagreement over financial affairs (P = 0.005) contributed to actor paths and only sidedness in relationships with parents showed significant negative association to marital quality in actor-to-partner paths. Conclusions: Different themes of conflict contribute to the diminished level of marital quality in early and late stages of the marriage. Conflicts over sex, relationship with extended family and daily hassles are emphasized in the early years of marriage, while in later years; dispute over money and daily hassles dominate. PMID:26097856
Chen, Chun-lan; Wu, Min-na; Wei, Wen-xue
2011-05-01
The aim of this study was to determine the effect of long-term (16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and the phylogenetic tree showed that the amoA genes detected in our study had a similarity with the uncultured gene of amoA, which showed some similar to Nitrosospira. Otherwise, the hao genes cloned showed a relationship to the genes of cultured bacteria such as Silicibacteria, Nitrosospira and Methylococcus, and the hao genes found in the N treatment dominated in alpha-Proteobacteria. These results suggest that long-term fertilization of nitrogen had significant impacts on the diversity or community of amoA and hao genes.
Humanities in undergraduate medical education: a literature review.
Ousager, Jakob; Johannessen, Helle
2010-06-01
Humanities form an integral part of undergraduate medical curricula at numerous medical schools all over the world, and medical journals publish a considerable quantity of articles in this field. The aim of this study was to determine the extent to which the literature on humanities in undergraduate medical education seeks to provide evidence of a long-term impact of this integration of humanities in undergraduate medical education. Medline was searched for publications concerning the humanities in undergraduate medical education appearing from January 2000 to December 2008. All articles were manually sorted by the authors. Two hundred forty-five articles were included in the study. Following a qualitative analysis, the references included were categorized as "pleading the case," "course descriptions and evaluations," "seeking evidence of long-term impact," or "holding the horses." Two hundred twenty-four articles out of 245 either praised the (potential) effects of humanities on medical education or described existing or planned courses without offering substantial evidence of any long-term impact of these curricular activities on medical proficiency. Only 9 articles provided evidence of attempts to document long-term impacts using diverse test tools, and 10 articles presented relatively reserved attitudes toward humanities in undergraduate medical education. Evidence on the positive long-term impacts of integrating humanities into undergraduate medical education is sparse. This may pose a threat to the continued development of humanities-related activities in undergraduate medical education in the context of current demands for evidence to demonstrate educational effectiveness.
Dixit, Prakash N; Telleria, Roberto
2015-04-01
Inter-annual and seasonal variability in climatic parameters, most importantly rainfall, have potential to cause climate-induced risk in long-term crop production. Short-term field studies do not capture the full nature of such risk and the extent to which modifications to crop, soil and water management recommendations may be made to mitigate the extent of such risk. Crop modeling studies driven by long-term daily weather data can predict the impact of climate-induced risk on crop growth and yield however, the availability of long-term daily weather data can present serious constraints to the use of crop models. To tackle this constraint, two weather generators namely, LARS-WG and MarkSim, were evaluated in order to assess their capabilities of reproducing frequency distributions, means, variances, dry spell and wet chains of observed daily precipitation, maximum and minimum temperature, and solar radiation for the eight locations across cropping areas of Northern Syria and Lebanon. Further, the application of generated long-term daily weather data, with both weather generators, in simulating barley growth and yield was also evaluated. We found that overall LARS-WG performed better than MarkSim in generating daily weather parameters and in 50 years continuous simulation of barley growth and yield. Our findings suggest that LARS-WG does not necessarily require long-term e.g., >30 years observed weather data for calibration as generated results proved to be satisfactory with >10 years of observed data except in area with higher altitude. Evaluating these weather generators and the ability of generated weather data to perform long-term simulation of crop growth and yield is an important first step to assess the impact of future climate on yields, and to identify promising technologies to make agricultural systems more resilient in the given region. Copyright © 2015 Elsevier B.V. All rights reserved.
Huntley, E; Smith, L
1999-12-01
Encopresis is a major problem in high-dependency fields such as intellectual disability. Little information is available with respect to either the prevalence or aetiology of encopresis, probably because it is widely regarded as part and parcel of the handicapping condition. Consequently, treatment reports are rare and confined to a small number of case studies. There is a dearth of long-term follow-up on the behavioural treatment of encopresis in the general population, and no long-term follow-up studies are available for the treatment of encopresis in intellectual disability. The present report provides follow-up data for nine out of 10 people with mainly severe intellectual disability who had received behavioural treatment for primary retentive or non-retentive encopresis between 5 and 17 years previously. Six out of the nine subjects for whom data were available were accident-free and a further two clients were very substantially improved. Interestingly, those whose former encopresis was retentive in nature maintained more successfully, despite the severity of their original impaction. The limitations of the present study are discussed.
Dunford, James C; Estep, Alden S; Waits, Christy M; Richardson, Alec G; Hoel, David F; Horn, Karin; Walker, Todd W; Blersch, Jessika S; Kerce, Jerry D; Wirtz, Robert A
2018-02-23
In this semi-field study, a new polymer-enhanced deltamethrin formulation, K-Othrine ® PolyZone, was compared to a standard deltamethrin product for residual activity against a susceptible strain of laboratory-reared Anopheles gambiae using standard WHO cone bioassays. Residual insecticide efficacy was recorded after exposure to metal, cement and wood panels maintained in experimental huts in sub-tropical environmental conditions in north central Florida, USA, and panels stored in a climate controlled chamber located at the Centers for Disease Control and Prevention, Georgia, USA. K-Othrine ® PolyZone demonstrated 100% control on metal and cement panels 1 year post application and > 80% control on wood panels up to 6 mo. The new formulation should be considered for use in indoor residual spray programmes requiring long-term control of malaria vectors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rohrbaugh, Nathaniel; Bryan, Isaac; Bryan, Zachary
AlGaN/GaN Field Effect Transistors (FETs) are promising biosensing devices. Functionalization of these devices is explored in this study using an in situ approach with phosphoric acid etchant and a phosphonic acid derivative. Devices are terminated on peptides and soaked in water for up to 168 hrs to examine FETs for both device responses and surface chemistry changes. Measurements demonstrated threshold voltage shifting after the functionalization and soaking processes, but demonstrated stable FET behavior throughout. X-ray photoelectron spectroscopy and atomic force microscopy confirmed peptides attachment to device surfaces before and after water soaking. Results of this work point to the stabilitymore » of peptide coated functionalized AlGaN/GaN devices in solution and support further research of these devices as disposable, long term, in situ biosensors.« less
Monitoring and modeling of long-term settlements of an experimental landfill in Brazil.
Simões, Gustavo Ferreira; Catapreta, Cícero Antônio Antunes
2013-02-01
Settlement evaluation in sanitary landfills is a complex process, due to the waste heterogeneity, time-varying properties and influencing factors and mechanisms, such as mechanical compression due to load application and creep, and physical-chemical and biological processes caused by the wastes decomposition. Many empirical models for the analysis of long-term settlement in landfills are reported in the literature. This paper presents the results of a settlement monitoring program carried out during 6 years in Belo Horizonte experimental landfill. Different sets of field data were used to calibrate three long-term settlement prediction models (rheological, hyperbolic and composite). The parameters obtained in the calibration were used to predict the settlements and to compare with actual field data. During the monitoring period of 6 years, significant vertical strains were observed (of up to 31%) in relation to the initial height of the experimental landfill. The results for the long-term settlement prediction obtained by the hyperbolic and rheological models significantly underestimate the settlements, regardless the period of data used in the calibration. The best fits were obtained with the composite model, except when 1 year field data were used in the calibration. The results of the composite model indicate settlements stabilization at larger times and with larger final settlements when compared to the hyperbolic and rheological models. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bamford, Ruth; Kellett, Barry; Bradford, John; Todd, Tom N.; Stafford-Allen, Robin; Alves, E. Paulo; Silva, Luis; Collingwood, Cheryl; Crawford, Ian A.; Bingham, Robert
2014-12-01
In this paper we explore the effectiveness of an artificial mini-magnetosphere as a potential radiation shelter for long term human space missions. Our study includes the differences that the plasma environment makes to the efficiency of the shielding from the high energy charged particle component of solar and cosmic rays, which radically alters the power requirements. The incoming electrostatic charges are shielded by fields supported by the self captured environmental plasma of the solar wind, potentially augmented with additional density. The artificial magnetic field generated on board acts as the means of confinement and control. Evidence for similar behaviour of electromagnetic fields and ionised particles in interplanetary space can be gained by the example of the enhanced shielding effectiveness of naturally occurring "mini-magnetospheres" on the moon. The shielding effect of surface magnetic fields of the order of ~100s nanoTesla is sufficient to provide effective shielding from solar proton bombardment that culminate in visible discolouration of the lunar regolith known as "lunar swirls". Supporting evidence comes from theory, laboratory experiments and computer simulations that have been obtained on this topic. The result of this work is, hopefully, to provide the tools for a more realistic estimation of the resources versus effectiveness and risk that spacecraft engineers need to work with in designing radiation protection for long-duration human space missions.
The Long-term Post-outburst Spin Down and Flux Relaxation of Magnetar Swift J1822.3-1606
NASA Astrophysics Data System (ADS)
Scholz, P.; Kaspi, V. M.; Cumming, A.
2014-05-01
The magnetar Swift J1822.3-1606 entered an outburst phase in 2011 July. Previous X-ray studies of its post-outburst rotational evolution yielded inconsistent measurements of the spin-inferred magnetic field. Here we present the timing behavior and flux relaxation from over two years of Swift, RXTE, and Chandra observations following the outburst. We find that the ambiguity in previous timing solutions was due to enhanced spin down that resembles an exponential recovery following a glitch at the outburst onset. After fitting out the effects of the recovery, we measure a long-term spin-down rate of \\dot{\
USDA-ARS?s Scientific Manuscript database
Diminishing freshwater resources have brought attention to the reuse of degraded water as a water resource rather than a disposal problem. Drainage water from tile-drained, irrigated agricultural land is degraded water that is often in large supply, but the long-term impact and sustainability of it...
A Long-Term Model for the Curriculum of Training for an Electric-Power Specialist
ERIC Educational Resources Information Center
Venikov, V. A.
1978-01-01
Long-term planning for professional training of electric-power specialists in Russia will have to (1) recognize the need for specialists to adapt to unforeseen developments in the field, (2) include new mathematics, physics, and computer technology, and (3) be prepared for changes in methods of production and transformation of energy. (AV)
Long-term performance monitoring of hardwood timber bridges in Pennsylvania
James P. Wacker; Carlito Calil; Lola E. Hislop; Paula D. Hilbrich Lee; James A. Kainz
2004-01-01
Several hardwood timber bridges were constructed in Pennsylvania during the early 1990s. This report summarizes the long-term field performance of seven stress-laminated deck bridges over a 4-year period beginning August 1997 and ending July 2001. Data collected include lumber moisture content, static load test deflection measurements, and bridge condition assessments...
William S. Currie; Mark E. Harmon; Ingrid C. Burke; Stephen C. Hart; William J. Parton; Whendee L. Silver
2009-01-01
We analyzed results from 10-year long field incubations of foliar and fine root litter from the Long-term lntersite Decomposition Experiment Team (LIDET) study. We tested whether a variety of climate and litter quality variables could be used to develop regression models of decomposition parameters across wide ranges in litter quality and climate and whether these...
Replicating annual North Atlantic hurricane activity 1878-2012 from environmental variables
NASA Astrophysics Data System (ADS)
Saunders, Mark A.; Klotzbach, Philip J.; Lea, Adam S. R.
2017-06-01
Statistical models can replicate annual North Atlantic hurricane activity from large-scale environmental field data for August and September, the months of peak hurricane activity. We assess how well the six environmental fields used most often in contemporary statistical modeling of seasonal hurricane activity replicate North Atlantic hurricane numbers and Accumulated Cyclone Energy (ACE) over the 135 year period from 1878 to 2012. We find that these fields replicate historical hurricane activity surprisingly well, showing that contemporary statistical models and their seasonal physical links have long-term robustness. We find that August-September zonal trade wind speed over the Caribbean Sea and the tropical North Atlantic is the environmental field which individually replicates long-term hurricane activity the best and that trade wind speed combined with the difference in sea surface temperature between the tropical Atlantic and the tropical mean is the best multi-predictor model. Comparing the performance of the best single-predictor and best multi-predictor models shows that they exhibit little difference in hindcast skill for predicting long-term ACE but that the best multipredictor model offers improved skill for predicting long-term hurricane numbers. We examine whether replicated real-time prediction skill 1983-2012 increases as the model training period lengthens and find evidence that this happens slowly. We identify a dropout in hurricane replication centered on the 1940s and show that this is likely due to a decrease in data quality which affects all data sets but Atlantic sea surface temperatures in particular. Finally, we offer insights on the implications of our findings for seasonal hurricane prediction.
Heart transplantation: challenges facing the field.
Tonsho, Makoto; Michel, Sebastian; Ahmed, Zain; Alessandrini, Alessandro; Madsen, Joren C
2014-05-01
There has been significant progress in the field of heart transplantation over the last 45 years. The 1-yr survival rates following heart transplantation have improved from 30% in the 1970s to almost 90% in the 2000s. However, there has been little change in long-term outcomes. This is mainly due to chronic rejection, malignancy, and the detrimental side effects of chronic immunosuppression. In addition, over the last decade, new challenges have arisen such as increasingly complicated recipients and antibody-mediated rejection. Most, if not all, of these obstacles to long-term survival could be prevented or ameliorated by the induction of transplant tolerance wherein the recipient's immune system is persuaded not to mount a damaging immune response against donor antigens, thus eliminating the need for chronic immunosuppression. However, the heart, as opposed to other allografts like kidneys, appears to be a tolerance-resistant organ. Understanding why organs like kidneys and livers are prone to tolerance induction, whereas others like hearts and lungs are tolerance-resistant, could aid in our attempts to achieve long-term, immunosuppression-free survival in human heart transplant recipients. It could also advance the field of pig-to-human xenotransplantation, which, if successful, would eliminate the organ shortage problem. Of course, there are alternative futures to the field of heart transplantation that may include the application of total mechanical support, stem cells, or bioengineered whole organs. Which modality will be the first to reach the ultimate goal of achieving unlimited, long-term, circulatory support with minimal risk to longevity or lifestyle is unknown, but significant progress in being made in each of these areas.
Heart Transplantation: Challenges Facing the Field
Tonsho, Makoto; Michel, Sebastian; Ahmed, Zain; Alessandrini, Alessandro; Madsen, Joren C.
2014-01-01
There has been significant progress in the field of heart transplantation over the last 45 years. The 1-yr survival rates following heart transplantation have improved from 30% in the 1970s to almost 90% in the 2000s. However, there has been little change in long-term outcomes. This is mainly due to chronic rejection, malignancy, and the detrimental side effects of chronic immunosuppression. In addition, over the last decade, new challenges have arisen such as increasingly complicated recipients and antibody-mediated rejection. Most, if not all, of these obstacles to long-term survival could be prevented or ameliorated by the induction of transplant tolerance wherein the recipient’s immune system is persuaded not to mount a damaging immune response against donor antigens, thus eliminating the need for chronic immunosuppression. However, the heart, as opposed to other allografts like kidneys, appears to be a tolerance-resistant organ. Understanding why organs like kidneys and livers are prone to tolerance induction, whereas others like hearts and lungs are tolerance-resistant, could aid in our attempts to achieve long-term, immunosuppression-free survival in human heart transplant recipients. It could also advance the field of pig-to-human xenotransplantation, which, if successful, would eliminate the organ shortage problem. Of course, there are alternative futures to the field of heart transplantation that may include the application of total mechanical support, stem cells, or bioengineered whole organs. Which modality will be the first to reach the ultimate goal of achieving unlimited, long-term, circulatory support with minimal risk to longevity or lifestyle is unknown, but significant progress in being made in each of these areas. PMID:24789875
Shao, Xingfang; Zhu, Ping; Zhang, Wenju; Xu, Minggang; Murphy, Daniel V.
2016-01-01
Long-term manure application is recognized as an efficient management practice to enhance soil organic carbon (SOC) accumulation and nitrogen (N) mineralization capacity. A field study was established in 1979 to understand the impact of long-term manure and/or chemical fertilizer application on soil fertility in a continuous maize cropping system. Soil samples were collected from field plots in 2012 from 9 fertilization treatments (M0CK, M0N, M0NPK, M30CK, M30N, M30NPK, M60CK, M60N, and M60NPK) where M0, M30, and M60 refer to manure applied at rates of 0, 30, and 60 t ha−1 yr−1, respectively; CK indicates no fertilizer; N and NPK refer to chemical fertilizer in the forms of either N or N plus phosphorus (P) and potassium (K). Soils were separated into three particle-size fractions (2000–250, 250–53, and <53 μm) by dry- and wet-sieving. A laboratory incubation study of these separated particle-size fractions was used to evaluate the effect of long-term manure, in combination with/without chemical fertilization application, on the accumulation and mineralization of SOC and total N in each fraction. Results showed that long-term manure application significantly increased SOC and total N content and enhanced C and N mineralization in the three particle-size fractions. The content of SOC and total N followed the order 2000–250 μm > 250–53μm > 53 μm fraction, whereas the amount of C and N mineralization followed the reverse order. In the <53 μm fraction, the M60NPK treatment significantly increased the amount of C and N mineralized (7.0 and 10.1 times, respectively) compared to the M0CK treatment. Long-term manure application, especially when combined with chemical fertilizers, resulted in increased soil microbial biomass C and N, and a decreased microbial metabolic quotient. Consequently, long-term manure fertilization was beneficial to both soil C and N turnover and microbial activity, and had significant effect on the microbial metabolic quotient. PMID:27031697
Acetylcholine and Olfactory Perceptual Learning
ERIC Educational Resources Information Center
Wilson, Donald A.; Fletcher, Max L.; Sullivan, Regina M.
2004-01-01
Olfactory perceptual learning is a relatively long-term, learned increase in perceptual acuity, and has been described in both humans and animals. Data from recent electrophysiological studies have indicated that olfactory perceptual learning may be correlated with changes in odorant receptive fields of neurons in the olfactory bulb and piriform…
Simplifying field-scale assessment of spatiotemporal changes of soil salinity
USDA-ARS?s Scientific Manuscript database
Monitoring soil salinity (ECe) is important to properly plan agronomic and irrigation practices. Salinity can be readily measured through soil sampling directed by geospatial measurements of apparent soil electrical conductivity (ECa). Using data from a long-term (1999-2012) monitoring study at a 32...
Uncertainty of water budget closure across the Long-Term Agroecosystems Research network
USDA-ARS?s Scientific Manuscript database
Quantification of the various components of the hydrologic budget at a site (precipitation, evaporation, runoff,…) gives important indications about major and minor hydrologic processes controlling field and watershed scale response. The objectives of this study were to: 1) develop hydrologic budget...
The dynamics of zooxanthellae populations: A long-term study in the field
Fagoonee; Wilson; Hassell; Turner
1999-02-05
Coral bleaching characterized by the expulsion of symbiotic algae (zooxanthellae) is an increasing problem worldwide. Global warming has been implicated as one cause, but the phenomenon cannot be fully comprehended without an understanding of the variability of zooxanthellae populations in field conditions. Results from a 6-year field study are presented, providing evidence of density regulation but also of large variability in the zooxanthellae population with regular episodes of very low densities. These bleaching events are likely to be part of a constant variability in zooxanthellae density caused by environmental fluctuations superimposed on a strong seasonal cycle in abundance.
Assessment of short/long term electric field strength measurements for a pilot district
NASA Astrophysics Data System (ADS)
Kurnaz, Cetin; Yildiz, Dogan; Karagol, Serap
2018-03-01
The level of electromagnetic radiation (EMR) exposure increases day by day as natural consequences of technological developments. In recent years, the increasing use of cellular systems has made it necessary to measure and evaluate EMR originating from base stations. In this study, broadband and band selective electric field strength (E) measurements were taken at four different times in order to evaluate the change of short term E in Atakum district of Samsun, Turkey. The measurements were collected from 46 different locations using a SRM 3006 and a PMM 8053 EMR meter in a band from 100 kHz to 3 GHz, and the maximum E (Emax) and the average E (Eavg) were recorded. The highest values have been noticed in these measurements at 9.45 V/m and 17.53 V/m for Eavg and Emax respectively. Apart from these measurements, 24 hour long term E measurements were taken at a location where the highest value was observed and analyzed, to observe the change of Es during a day. At the end of the study, a tentative mathematical model that helps in computing the total E of the medium with 95% accuracy, was obtained.
Field Scale Optimization for Long-Term Sustainability of Best Management Practices in Watersheds
NASA Astrophysics Data System (ADS)
Samuels, A.; Babbar-Sebens, M.
2012-12-01
Agricultural and urban land use changes have led to disruption of natural hydrologic processes and impairment of streams and rivers. Multiple previous studies have evaluated Best Management Practices (BMPs) as means for restoring existing hydrologic conditions and reducing impairment of water resources. However, planning of these practices have relied on watershed scale hydrologic models for identifying locations and types of practices at scales much coarser than the actual field scale, where landowners have to plan, design and implement the practices. Field scale hydrologic modeling provides means for identifying relationships between BMP type, spatial location, and the interaction between BMPs at a finer farm/field scale that is usually more relevant to the decision maker (i.e. the landowner). This study focuses on development of a simulation-optimization approach for field-scale planning of BMPs in the School Branch stream system of Eagle Creek Watershed, Indiana, USA. The Agricultural Policy Environmental Extender (APEX) tool is used as the field scale hydrologic model, and a multi-objective optimization algorithm is used to search for optimal alternatives. Multiple climate scenarios downscaled to the watershed-scale are used to test the long term performance of these alternatives and under extreme weather conditions. The effectiveness of these BMPs under multiple weather conditions are included within the simulation-optimization approach as a criteria/goal to assist landowners in identifying sustainable design of practices. The results from these scenarios will further enable efficient BMP planning for current and future usage.
Global biodiversity monitoring: from data sources to essential biodiversity variables
Proenca, Vania; Martin, Laura J.; Pereira, Henrique M.; Fernandez, Miguel; McRae, Louise; Belnap, Jayne; Böhm, Monika; Brummitt, Neil; Garcia-Moreno, Jaime; Gregory, Richard D.; Honrado, Joao P; Jürgens, Norbert; Opige, Michael; Schmeller, Dirk S.; Tiago, Patricia; van Sway, Chris A
2016-01-01
Essential Biodiversity Variables (EBVs) consolidate information from varied biodiversity observation sources. Here we demonstrate the links between data sources, EBVs and indicators and discuss how different sources of biodiversity observations can be harnessed to inform EBVs. We classify sources of primary observations into four types: extensive and intensive monitoring schemes, ecological field studies and satellite remote sensing. We characterize their geographic, taxonomic and temporal coverage. Ecological field studies and intensive monitoring schemes inform a wide range of EBVs, but the former tend to deliver short-term data, while the geographic coverage of the latter is limited. In contrast, extensive monitoring schemes mostly inform the population abundance EBV, but deliver long-term data across an extensive network of sites. Satellite remote sensing is particularly suited to providing information on ecosystem function and structure EBVs. Biases behind data sources may affect the representativeness of global biodiversity datasets. To improve them, researchers must assess data sources and then develop strategies to compensate for identified gaps. We draw on the population abundance dataset informing the Living Planet Index (LPI) to illustrate the effects of data sources on EBV representativeness. We find that long-term monitoring schemes informing the LPI are still scarce outside of Europe and North America and that ecological field studies play a key role in covering that gap. Achieving representative EBV datasets will depend both on the ability to integrate available data, through data harmonization and modeling efforts, and on the establishment of new monitoring programs to address critical data gaps.
The Epidemiology of Longevity and Exceptional Survival
Newman, Anne B.; Murabito, Joanne M.
2013-01-01
The field of the “epidemiology of longevity” has been expanding rapidly in recent years. Several long-term cohort studies have followed older adults long enough to identify the most long-lived and to define many factors that lead to a long life span. Very long-lived people such as centenarians have been examined using case-control study designs. Both cohort and case-control studies have been the subject of genome-wide association studies that have identified genetic variants associated with longevity. With growing recognition of the importance of rare variations, family studies of longevity will be useful. Most recently, exome and whole-genome sequencing, gene expression, and epigenetic studies have been undertaken to better define functional variation and regulation of the genome. In this review, we consider how these studies are leading to a deeper understanding of the underlying biologic pathways to longevity. PMID:23372024
Long-term performance of passive materials for removal of ozone from indoor air.
Cros, C J; Morrison, G C; Siegel, J A; Corsi, R L
2012-02-01
The health effects associated with exposure to ozone range from respiratory irritation to increased mortality. In this paper, we explore the use of three green building materials and an activated carbon (AC) mat that remove ozone from indoor air. We studied the effects of long-term exposure of these materials to real environments on ozone removal capability and pre- and post-ozonation emissions. A field study was completed over a 6-month period, and laboratory testing was intermittently conducted on material samples retrieved from the field. The results show sustained ozone removal for all materials except recycled carpet, with greatest ozone deposition velocity for AC mat (2.5-3.8 m/h) and perlite-based ceiling tile (2.2-3.2 m/h). Carbonyl emission rates were low for AC across all field sites. Painted gypsum wallboard and perlite-based ceiling tile had similar overall emission rates over the 6-month period, while carpet had large initial emission rates of undesirable by-products that decayed rapidly but remained high compared with other materials. This study confirms that AC mats and perlite-based ceiling tile are viable surfaces for inclusion in buildings to remove ozone without generating undesirable by-products. PRACTICAL IMPLICATIONS The use of passive removal materials for ozone control could decrease the need for, or even render unnecessary, active but energy consuming control solutions. In buildings where ozone should be controlled (high outdoor ozone concentrations, sensitive populations), materials specifically designed or selected for removing ozone could be implemented, as long as ozone removal is not associated with large emissions of harmful by-products. We find that activated carbon mats and perlite-based ceiling tiles can provide substantial, long-lasting, ozone control. © 2011 John Wiley & Sons A/S.
Kremeike, K; Mohr, A; Kampschulte, R; Bergmann, J; Beil, S; Neuhaus, U; Dierks, M-L; Driftmann, C; Duhr, A; Groeneveld, S; Kaspar, M; Kowollik, G; Miest, H-H; Schene, I; Reinhardt, D
2016-11-01
Background: In Germany some 2 000 children and adolescent are diagnosed with cancer every year. Curing rates are increasing and therewith also the number of survivors is growing. Survivors frequently suffer from long-term effects of the disease and its treatment, but long-term follow-up care shows deficits. Method: The Network for oncological advisory service (NOF) started in 11/2013, researching and building up a network of available support in Lower Saxony. A telephone hotline was installed in 01/2014 in order to advice survivors on their problems. At the same time, an interview study on survivors needs was conducted throughout Germany. Results: In the first 2 years, the NOF gave advice to 79 patients. Whilst enquiries of medical or psychological nature were transferred to the cooperation partner, requests on psychosocial and social legal issues are being deled by the NOF due to lack of appropriate partners. The evaluation of 25 interviews shows key issues in long-term after-care: (1) transition from acute therapy to everyday life, (2) problems due to pediatric cancer and therapy, (3) patients perception of own disposition, (4) social reactions towards survivors, (5) structure of long-term follow-up care, (6) information flow. Conclusion: Many survivors suffer from long-term effects of cancer and treatment. The lack of available contact person and being in limbo between cured and simultaneously affected by the cancer treatment and chronic diseases is perceived as being problematic. This translates to various requirements on a patient-oriented long-term care, mainly in the psychosocial field. © Georg Thieme Verlag KG Stuttgart · New York.
MAGNETIC FLUX TRANSPORT AND THE LONG-TERM EVOLUTION OF SOLAR ACTIVE REGIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ugarte-Urra, Ignacio; Upton, Lisa; Warren, Harry P.
2015-12-20
With multiple vantage points around the Sun, Solar Terrestrial Relations Observatory (STEREO) and Solar Dynamics Observatory imaging observations provide a unique opportunity to view the solar surface continuously. We use He ii 304 Å data from these observatories to isolate and track ten active regions and study their long-term evolution. We find that active regions typically follow a standard pattern of emergence over several days followed by a slower decay that is proportional in time to the peak intensity in the region. Since STEREO does not make direct observations of the magnetic field, we employ a flux-luminosity relationship to infermore » the total unsigned magnetic flux evolution. To investigate this magnetic flux decay over several rotations we use a surface flux transport model, the Advective Flux Transport model, that simulates convective flows using a time-varying velocity field and find that the model provides realistic predictions when information about the active region's magnetic field strength and distribution at peak flux is available. Finally, we illustrate how 304 Å images can be used as a proxy for magnetic flux measurements when magnetic field data is not accessible.« less
Estimating post-fire organic soil depth in the Alaskan boreal forest using the Normalized Burn Ratio
D. Verbyla; R. Lord
2008-01-01
As part of a long-term moose browse/fire severity study, we used the Normalized Burn Ratio (NBR) with historic Landsat Thematic Mapper (TM) imagery to estimate fire severity from a 1983 wildfire in interior Alaska. Fire severity was estimated in the field by measuring the depth of the organic soil at 57 sites during the summer of 2006. Sites were selected for field...
Goulas, Anaïs; Sabourin, Lyne; Asghar, Farah; Haudin, Claire-Sophie; Benoit, Pierre; Topp, Edward
2018-06-01
Antibiotics are frequently introduced into agricultural soils with the application of sewage sludge or farm organic fertilizers. Repeated exposure of soils to a pollutant can enrich for microbial populations that metabolize the chemical, reducing its environmental persistence. In London, Canada, soils from a long-term field experiment have received different concentrations of antibiotics annually for several years. The purpose of the present study was to assess the bioavailability of sulfamethazine, erythromycin, or ciprofloxacin through aqueous extractions with borax or EDTA solutions and their biodegradation following different soil exposure scenarios. Control soils and soils treated annually in the field with 10 mg antibiotics per kg were sampled, supplemented in the laboratory with radiolabeled antibiotic either added directly or carried in dairy manure. Sulfamethazine and erythromycin were initially more bioavailable than ciprofloxacin, with aqueous extractabilities representing 60, 36, and 8%, respectively. Sulfamethazine and erythromycin were degraded in soils, with a larger fraction mineralized in the long-term exposed soil (20 and 65%, respectively) than in control soil (0.4 and 3%, respectively) after 7 days of incubation. In contrast, ciprofloxacin was not mineralized neither in control nor long-term exposed soils. The mineralized fractions were similar for antibiotics added directly to soil or carried in dairy manure.
Aliuos, Pooyan; Schulze, Jennifer; Schomaker, Markus; Reuter, Günter; Stolle, Stefan R. O.; Werner, Darja; Ripken, Tammo; Lenarz, Thomas; Warnecke, Athanasia
2016-01-01
Introduction Long-term drug delivery to the inner ear may be achieved by functionalizing cochlear implant (CI) electrodes with cells providing neuroprotective factors. However, effective strategies in order to coat implant surfaces with cells need to be developed. Our vision is to make benefit of electromagnetic field attracting forces generated by CI electrodes to bind BDNF-secreting cells that are labelled with magnetic beads (MB) onto the electrode surfaces. Thus, the effect of MB-labelling on cell viability and BDNF production were investigated. Materials and Methods Murine NIH 3T3 fibroblasts—genetically modified to produce BDNF—were labelled with MB. Results Atomic force and bright field microscopy illustrated the internalization of MB by fibroblasts after 24 h of cultivation. Labelling cells with MB did not expose cytotoxic effects on fibroblasts and allowed adhesion on magnetic surfaces with sufficient BDNF release. Discussion Our data demonstrate a novel approach for mediating enhanced long-term adhesion of BDNF-secreting fibroblasts on model electrode surfaces for cell-based drug delivery applications in vitro and in vivo. This therapeutic strategy, once transferred to cells suitable for clinical application, may allow the biological modifications of CI surfaces with cells releasing neurotrophic or other factors of interest. PMID:26918945
Nearshore shore-oblique bars, gravel outcrops, and their correlation to shoreline change
Schupp, C.A.; McNinch, J.E.; List, J.H.
2006-01-01
This study demonstrates the physical concurrence of shore-oblique bars and gravel outcrops in the surf zone along the northern Outer Banks of North Carolina. These subaqueous features are spatially correlated with shoreline change at a range of temporal and spatial scales. Previous studies have noted the existence of beach-surf zone interactions, but in general, relationships between nearshore geological features and coastal change are poorly understood. These new findings should be considered when exploring coastal zone dynamics and developing predictive engineering models.The surf zone and nearshore region of the Outer Banks is predominantly planar and sandy, but there are several discrete regions with shore-oblique bars and interspersed gravel outcrops. These bar fields have relief up to 3 m, are several kilometers wide, and were relatively stationary over a 1.5 year survey period; however, the shoreward component of the bar field does exhibit change during this time frame. All gravel outcrops observed in the study region, a 40 km longshore length, were located adjacent to a shore-oblique bar, in a trough that had width and length similar to that of the associated bar. Seismic surveys show that the outcrops are part of a gravel stratum underlying the active surface sand layer.Cross-correlation analyses demonstrate high correlation of monthly and multi-decadal shoreline change rates with the adjacent surf-zone bathymetry and sediment distribution. Regionally, areas with shore-oblique bars and gravel outcrops are correlated with on-shore areas of high short-term shoreline variability and high long-term shoreline change rates. The major peaks in long-term shoreline erosion are onshore of shore-oblique bars, but not all areas with high rates of long-term shoreline change are associated with shore-oblique bars and troughs.
ERIC Educational Resources Information Center
Maltby, Jennifer L.; Brooks, Christopher; Horton, Marjorie; Morgan, Helen
2016-01-01
Science, technology, engineering and math (STEM) degrees provide opportunities for economic mobility. Yet women, underrepresented minority (URM), and first-generation college students remain disproportionately underrepresented in STEM fields. This study examined the effectiveness of a living-learning community (LLC) for URM and first-generation…
Solar diameter measurements for study of Sun climate coupling
NASA Technical Reports Server (NTRS)
Hill, H. A.
1983-01-01
Changes in solar shape and diameter were detected as a possible probe of variability in solar luminosity, an important climatic driving function. A technique was designed which will allow the calibration of the telescope field, providing a scale for long-term comparison of these and future measurements.
USDA-ARS?s Scientific Manuscript database
Background and aims: Root functional traits are determinants of soil carbon storage; plant productivity; and ecosystemproperties. However, few studies look at both annual and perennial roots, soil properties, and productivity in the context of field scale agricultural systems. Methods: In Long Term...
E. Gregory McPherson; Paula J. Peper
2012-01-01
This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...
TRACKING CHANGES IN WETLANDS WITH URBANIZATION: SIXTEEN YEARS OF EXPERIENCE IN PORTLAND, OREGON, USA
Long-term studies of the wetland resource in urbanizing areas are essential to understanding the effects of urbanization on wetlands and the effectiveness of management actions. Using data from the National Wetland Inventory (NWI) in combination with field surveys, we tracked ch...
USDA-ARS?s Scientific Manuscript database
Biofuel feedstocks are being developed and evaluated in the United States and Europe to partially offset petroleum transport fuels. Accurate accounting of upstream and downstream greenhouse gas (GHG) emissions is necessary to measure the overall carbon intensity of new biofuel feedstocks. Changes in...
2002-11-01
synopsis of the collected data and collection methods, as well as a preliminary report of remarkable or unusual conditions in the system. They are intended...resource requires scientific understanding of the ecosystem and of its long-term trends and conditions . To meet this need, Congress authorized a Long...chemical oxygen demand, biochemical oxygen demand, total coliform bacteria , fecal coliform bacteria , fecal streptococcus, heavy metals, pesticides, and
Ederer, F; Gaasterland, D E; Sullivan, E K
1994-08-01
Medical therapy has been the standard initial treatment for open-angle glaucoma. When some visual field has been lost and maximum tolerated and effective medical therapy does not succeed in controlling the disease, the patient is considered to have advanced glaucoma, and the first of a potential sequence of surgical treatments is usually indicated. Little is known about the long-term course and prognosis of advanced glaucoma or about the long-term effectiveness of sequential surgical treatments in controlling the disease and preventing vision loss and blindness. The Advanced Glaucoma Intervention Study was designed to study, in advanced glaucoma, the long-term clinical course and prognosis, and, in a randomized trial, the comparative outcomes of two sequences of surgical treatments. Toward these goals, 789 eyes in 591 patients were enrolled at 11 clinical centers between 1988 and 1992. Follow-up will continue until 1996. Eyes were randomly assigned to one of two sequences of surgical treatments. One sequence begins with argon laser trabeculoplasty (ALT), is followed by trabeculectomy, an incisional surgical filtering procedure, should ALT fail to control the disease, and by a second trabeculectomy should the first trabeculectomy fail. The other sequence begins with trabeculectomy, is followed by ALT should the trabeculectomy fail, and by a second trabeculectomy should ALT fail. The main outcome of interest is visual function (visual field and visual acuity). Other important outcomes are intraocular pressure, complications of surgery, time to treatment failure, and extent of need for additional medical therapy. We present in this paper the rationale, objectives, design and methods of the study, and the baseline characteristics of study patients and eyes.
Ren, Weibo; Hu, Ningning; Hou, Xiangyang; Zhang, Jize; Guo, Huiqin; Liu, Zhiying; Kong, Lingqi; Wu, Zinian; Wang, Hui; Li, Xiliang
2017-01-01
Previous studies of transgenerational plasticity have demonstrated that long-term overgrazing experienced by Leymus chinensis , an ecologically dominant, rhizomatous grass species in eastern Eurasian temperate grassland, significantly affects its clonal growth in subsequent generations. However, there is a dearth of information on the reasons underlying this overgrazing-induced memory effect in plant morphological plasticity. We characterized the relationship between a dwarf phenotype and photosynthesis function decline of L. chinensis from the perspective of leaf photosynthesis by using both field measurement and rhizome buds culture cultivated in a greenhouse. Leaf photosynthetic functions (net photosynthetic rate, stomatal conductance, intercellular carbon dioxide concentration, and transpiration rate) were significantly decreased in smaller L. chinensis individuals that were induced to have a dwarf phenotype by being heavily grazed in the field. This decreased photosynthetic function was maintained a generation after greenhouse tests in which grazing was excluded. Both the response of L. chinensis morphological traits and photosynthetic functions in greenhouse were deceased relative to those in the field experiment. Further, there were significant decreases in leaf chlorophyll content and Rubisco enzyme activities of leaves between bud-cultured dwarf and non-dwarf L. chinensis in the greenhouse. Moreover, gene expression patterns showed that the bud-cultured dwarf L. chinensis significantly down-regulated (by 1.86- to 5.33-fold) a series of key genes that regulate photosynthetic efficiency, stomata opening, and chloroplast development compared with the non-dwarf L. chinensis . This is among the first studies revealing a linkage between long-term overgrazing affecting the transgenerational morphological plasticity of clonal plants and physiologically adaptive photosynthesis function. Overall, clonal transgenerational effects in L. chinensis phenotypic traits heavily involve photosynthetic plasticity.
Ren, Weibo; Hu, Ningning; Hou, Xiangyang; Zhang, Jize; Guo, Huiqin; Liu, Zhiying; Kong, Lingqi; Wu, Zinian; Wang, Hui; Li, Xiliang
2017-01-01
Previous studies of transgenerational plasticity have demonstrated that long-term overgrazing experienced by Leymus chinensis, an ecologically dominant, rhizomatous grass species in eastern Eurasian temperate grassland, significantly affects its clonal growth in subsequent generations. However, there is a dearth of information on the reasons underlying this overgrazing-induced memory effect in plant morphological plasticity. We characterized the relationship between a dwarf phenotype and photosynthesis function decline of L. chinensis from the perspective of leaf photosynthesis by using both field measurement and rhizome buds culture cultivated in a greenhouse. Leaf photosynthetic functions (net photosynthetic rate, stomatal conductance, intercellular carbon dioxide concentration, and transpiration rate) were significantly decreased in smaller L. chinensis individuals that were induced to have a dwarf phenotype by being heavily grazed in the field. This decreased photosynthetic function was maintained a generation after greenhouse tests in which grazing was excluded. Both the response of L. chinensis morphological traits and photosynthetic functions in greenhouse were deceased relative to those in the field experiment. Further, there were significant decreases in leaf chlorophyll content and Rubisco enzyme activities of leaves between bud-cultured dwarf and non-dwarf L. chinensis in the greenhouse. Moreover, gene expression patterns showed that the bud-cultured dwarf L. chinensis significantly down-regulated (by 1.86- to 5.33-fold) a series of key genes that regulate photosynthetic efficiency, stomata opening, and chloroplast development compared with the non-dwarf L. chinensis. This is among the first studies revealing a linkage between long-term overgrazing affecting the transgenerational morphological plasticity of clonal plants and physiologically adaptive photosynthesis function. Overall, clonal transgenerational effects in L. chinensis phenotypic traits heavily involve photosynthetic plasticity. PMID:28484469
Quinones, Ferdinand; Balthrop, B.H.; Baker, E.G.
1988-01-01
This report contains a summation of 44 projects which were active in the Tennessee District during 1987 and 1988. Given in each summary is the name of the project chief, the objective of the project, the progress or results of the study to date, and the name of the cooperator. Hydrologic data are the backbone of the investigations conducted by the U.S Geological Survey (USGS). The basic data programs conducted by the Tennessee District provide streamflow, quality of water, and groundwater levels information essential to the assessment and management of the State 's water resources. Long-term streamflow, quality of water, and groundwater levels network are operated as part of the Hydrologic Data Section. Field operations are about equally divided among field offices in Memphis, Nashville, and Knoxville. A staff of about 40 engineers, hydrologists, and hydrologic technicians labor in the operation of the long-term network as well as short-term efforts in support of areal investigations. The data collected as part of the networks are published in the series of annual data reports. (USGS)
NASA Astrophysics Data System (ADS)
Thole, B. T.; Van Duijnen, P. Th.
1982-10-01
The induction and dispersion terms obtained from quantum-mechanical calculations with a direct reaction field hamiltonian are compared to second order perturbation theory expressions. The dispersion term is shown to give an upper bound which is a generalization of Alexander's upper bound. The model is illustrated by a calculation on the interactions in the water dimer. The long range Coulomb, induction and dispersion interactions are reasonably reproduced.
Capocchi, G; Della Torre, G; Grassi, S; Pettorossi, V E; Zampolini, M
1992-01-01
The effect of high frequency stimulation (HFS) of the primary vestibular afferents on field potentials recorded in the ipsilateral Medial Vestibular Nuclei (MVN) was studied. Our results show that potentiation and depression can be induced in different portions of MVN, which are distinguishable by their anatomical organization. HFS induces potentiation of the monosynaptic component in the ventral portion of the MVN, whereas it provokes depression of the polysynaptic component in the dorsal portion of the same nucleus. The induction of both potentiation and depression was blocked under AP5 perfusion, thus demonstrating that NMDA receptor activation mediates both phenomena. Furthermore, the finding that the field potentials were not modified during perfusion with DL-AP5, as previously reported, supports the hypothesis that NMDA receptors are not involved in the normal synaptic transmission from the primary vestibular afferent fibres, but are only activated following hyperstimulation of this afferent system. Our results suggest that the mechanisms of long term modification of synaptic efficacy observed in MVN may underlie the plasticity phenomena occurring in vestibular nuclei.
Nayak, D R; Babu, Y Jagadeesh; Datta, A; Adhya, T K
2007-01-01
Methane (CH4) oxidation is the only known biological sink process for mitigating atmospheric and terrestrial emissions of CH4, a major greenhouse gas. Methane oxidation in an alluvial soil planted to rice (Oryza sativa L.) under long-term application of organic (compost with a C/N ratio of 21.71), and mineral fertilizers was measured in a field-cum-laboratory incubation study. Oxidation rates were quantified in terms of decrease in the concentration of CH4 in the headspace of incubation vessels and expressed as half-life (t(1)2) values. Methane oxidation rates significantly differed among the treatments and growth stages of the rice crop. Methane oxidation rates were high at the maximum tillering and maturity stages, whereas they were low at grain-filling stage. Methane oxidation was low (t(1)2) = 15.76 d) when provided with low concentration of CH4. On the contrary, high concentration of CH4 resulted in faster oxidation (t(1)2) = 6.67 d), suggesting the predominance of "low affinity oxidation" in rice fields. Methane oxidation was stimulated following the application of mineral fertilizers or compost implicating nutrient limitation as one of the factors affecting the process. Combined application of compost and mineral fertilizer, however, inhibited CH4 oxidation probably due to N immobilization by the added compost. The positive effect of mineral fertilizer on CH4 oxidation rate was evident only at high CH4 concentration (t(1)2 = 4.80 d), while at low CH4 concentration their was considerable suppression (t(1) = 17.60 d). Further research may reveal that long-term application of fertilizers, organic or inorganic, may not inhibit CH4 oxidation.
Jabs, Douglas A.; Ahuja, Alka; Van Natta, Mark L.; Lyon, Alice T.; Yeh, Steven; Danis, Ronald
2015-01-01
Objectives To describe the long-term outcomes of patients with cytomegalovirus (CMV) retinitis and the acquired immunodeficiency syndrome (AIDS)in the modern era of combination antiretroviral therapy. Design Prospective, observational, cohort study Participants Patients with AIDS and CMV retinitis Testing Immune recovery, defined as a CD4+ T cell count>100 cells/μL for ≥ 3 months. Main outcome measures Mortality, visual impairment (visual acuity worse than 20/40) and blindness (visual acuity 20/200 or worse) on logarithmic visual acuity charts, loss of visual field on quantitative Goldmann perimetry. Results Patients without immune recovery had a mortality of 44.4/100 person years (PY), and a median survival of 13.5 months after the diagnosis of CMV retinitis, whereas those with immune recovery had a mortality of 2.7/100 PY (P<0.001), and an estimated median survival of 27.0 years after the diagnosis of CMV retinitis. The rates of bilateral visual impairment and blindness were 0.9/100 PY and 0.4/100 PY, respectively, and were similar between those with and without immune recovery. Among those with immune recovery, the rate of visual field loss was ~1% of the normal field/year, whereas among those without immune recovery it was ~7% of the normal field/year. Conclusions Among persons with CMV retinitis and AIDS, if there is immune recovery, long-term survival is likely, whereas if there is no immune recovery, the mortality rate is substantial. Although higher than the rates seen in the non-HIV-infected population, the rates of bilateral visual impairment and blindness are low, especially when compared to rates seen in the era before modern antiretroviral therapy. PMID:25892019
Jabs, Douglas A; Ahuja, Alka; Van Natta, Mark L; Lyon, Alice T; Yeh, Steven; Danis, Ronald
2015-07-01
To describe the long-term outcomes of patients with cytomegalovirus (CMV) retinitis and AIDS in the modern era of combination antiretroviral therapy. Prospective, observational cohort study. Patients with AIDS and CMV retinitis. Immune recovery, defined as a CD4+ T-cell count >100 cells/μl for ≥3 months. Mortality, visual impairment (visual acuity <20/40), and blindness (visual acuity ≤20/200) on logarithmic visual acuity charts and loss of visual field on quantitative Goldmann perimetry. Patients without immune recovery had a mortality of 44.4/100 person-years (PYs) and a median survival of 13.5 months after the diagnosis of CMV retinitis, whereas those with immune recovery had a mortality of 2.7/100 PYs (P < 0.001) and an estimated median survival of 27.0 years after the diagnosis of CMV retinitis. The rates of bilateral visual impairment and blindness were 0.9 and 0.4/100 PYs, respectively, and were similar between those with and without immune recovery. Among those with immune recovery, the rate of visual field loss was approximately 1% of the normal field per year, whereas among those without immune recovery it was approximately 7% of the normal field per year. Among persons with CMV retinitis and AIDS, if there is immune recovery, long-term survival is likely, whereas if there is no immune recovery, the mortality rate is substantial. Although higher than the rates in the population not infected by human immunodeficiency virus, the rates of bilateral visual impairment and blindness are low, especially when compared with rates in the era before modern antiretroviral therapy. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Baumwoll, Alma Aron
As education and neuroscience begin to merge, creating the new field of brain-based education, teachers are working to integrate scientific research into the classroom. While working to improve my own teaching, I developed a lesson plan to teach mitosis and meiosis through movement. My thesis reviews education theory and neuroscience to support using movement as a teaching tool in high-level, subject-based classrooms. I then outline my lesson plan and present my investigations of its effectiveness as demonstrated through short-term memory, long-term memory, and students' personal responses to the class. Two experiments were completed with biology lab sections at Northeastern University between 2009 and 2012; I taught my lesson to experimental groups while control groups learned through video-based lessons. The short-term study showed significant improvement in both the grades and enjoyment of the experimental groups. The long-term, retroactive study yielded no significant data, possibly due to weaknesses in the experimental design.
Huang, Yuqi; Zhao, Zhe; Wei, Xiaoli; Zheng, Yong; Yu, Jianqiang; Zheng, Jianquan; Wang, Liyun
2016-07-01
Clinical studies have shown an association between long-term anticholinergic (AC) drug exposure and Alzheimer's disease (AD) pathogenesis, which has been primarily investigated in Parkinson's disease (PD). However, long-term AC exposure as a risk factor for developing neurodegenerative disorders and the exact mechanisms and potential for disease progression remain unclear. Here, we have addressed the issue using trihexyphenidyl (THP), a commonly used AC drug in PD patients, to determine if THP can accelerate AD-like neurodegenerative progression and study potential mechanisms involved. Male Sprague-Dawley rats (SD) were intraperitoneally injected with THP (0.3 and 1.0 mg/kg) or normal saline (NS) for 7 months. Alterations in cognitive and behavioral performance were assessed using the Morris water maze (MWM) and open field tests. After behavior tests, whole genome oligo microarrays, quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR), immunohistochemistry, and immunofluorescence-confocal were used to investigate the global mechanisms underlying THP-induced neuropathology with aging. Compared with NS controls, the MWM test results showed that THP-treated rats exhibited significantly extended mean latencies during the initial 3 months of testing; however, this behavioral deficit was restored between the fourth and sixth month of MWM testing. The same tendencies were confirmed by MWM probe and open field tests. Gene microarray analysis identified 68 (47 %) upregulated and 176 (53 %) downregulated genes in the "THP-aging" vs. "NS-aging" group. The most significant populations of genes downregulated by THP were the immune response-, antigen processing and presentation-, and major histocompatibility complex (MHC)-related genes, as validated by qRT-PCR. The decreased expression of MHC class I in THP-treated aging brains was confirmed by confocal analysis. Notably, long-term THP treatment primed hippocampal and cortical microglia to undergo an inflammatory phenotypic switch, causing microgliosis and microglia activation, which were positively accompanied by pathological misfolded tau lesions. Our findings suggest that immune response and neuroinflammation represent a pivotal mechanism in THP-induced AD-like neuropathology processes with long-term exposure to AC drugs.
USDA-ARS?s Scientific Manuscript database
Diminishing freshwater resources have brought attention to the reuse of degraded water as a potential water resource rather than as a disposal problem. Drainage water from tile-drained, irrigated agricultural land is degraded water that is often in large supply, but the long-term impact and sustain...
Plazier, Mark; Tchen, Stephanie; Ost, Jan; Joos, Kathleen; De Ridder, Dirk; Vanneste, Sven
2015-10-01
Fibromyalgia is a disorder distinguished by pervasive musculoskeletal pain that has pervasive effects on affected individuals magnifying the importance of finding a safe and viable treatment option. The goal of this study is to investigate if transcranial direct current stimulation (tDCS) treatment can predict the outcome of occipital nerve field stimulation (ONFS) via a subcutaneous electrode. Nine patients with fibromyalgia were selected fulfilling the American College of Rheumatology-90 criteria. The patients were implanted with a subcutaneous trial-lead in the C2 dermatome innervated by the occipital nerve. After the treatment phase of ONFS using a C2 implant, each patient participated in three sessions of tDCS. Stimulation outcomes for pain suppression were examined between the two methods to determine possible correlations. Positive correlation of stimulation effect was noted between the numeric rating scale changes for pain obtained by tDCS treatments and short-term measures of ONFS, but no correlation was noted between tDCS and long-term ONFS outcomes. A correlation also was noted between short-term ONS C2 implant pain suppression and long-term ONS C2 implant treatment success. This pilot study suggests that tDCS is a predictive measure for success of OFNS in short-term but cannot be used as a predictive measure for success of long-term OFNS. Our data confirm previous findings that ONFS via an implanted electrode can improve fibromyalgia pain in a placebo-controlled way and exert a long-term pain suppression effect for ONFS via an implanted electrode. © 2015 International Neuromodulation Society.
Knowing when to assist: developmental issues in lifelong assistive robotics.
Demiris, Yiannis
2009-01-01
Children and adults with sensorimotor disabilities can significantly increase their autonomy through the use of assistive robots. As the field progresses from short-term, task-specific solutions to long-term, adaptive ones, new challenges are emerging. In this paper a lifelong methodological approach is presented, that attempts to balance the immediate context-specific needs of the user, with the long-term effects that the robot's assistance can potentially have on the user's developmental trajectory.
Krajňáková, Jana; Sutela, Suvi; Aronen, Tuija; Gömöry, Dušan; Vianello, Angelo; Häggman, Hely
2011-08-01
In coniferous species, including Greek fir (Abies cephalonica Loud), the involvement of somatic embryo plants in breeding and reforestation programs is dependent on the success of long-term cryostorage of embryogenic cultures during clonal field testing. In the present study on Greek fir, we assayed the recovery, morphological characteristics and genetic fidelity of embryogenic cell lines 6 and 8 during proliferation and maturation after long-term cryostorage. Our results indicate successful recovery of both cell lines after 6 years in cryostorage. In the maturation phase, both cell lines were capable of producing somatic embryos although some differences were detected among experiments. However, these changes were more dependent on the differences in the components of the maturation media or in the experimental set-up than on the long-term cryostorage. During both proliferation and maturation phases, the morphological fidelity of the embryogenic cultures as well as of the somatic embryos were alike before and after cryopreservation. The genetic fidelity of the cryopreserved cell line 6 that was assayed by random amplified polymorphic DNA (i.e. RAPD) markers demonstrated some changes in the RAPD profiles. The results indicate possible genetic aberrations caused by long-term cryopreservation or somaclonal variation during the proliferation stage. However, in spite of these changes the embryogenic cultures did not lose their proliferation or maturation abilities. Copyright © 2011 Elsevier Inc. All rights reserved.
Pressure measurements with a precision of 0.001 ppm in magnetic fields at low temperatures
NASA Astrophysics Data System (ADS)
Miura, Y.; Matsushima, N.; Ando, T.; Kuno, S.; Inoue, S.; Ito, K.; Mamiya, T.
1993-11-01
Pressure measurements made by an ac bridge technique with a precision of 0.001 ppm in magnetic fields at low temperatures using a Straty-Adams type gauge are described. In order to improve the sensitivity and the long-term stability of the bridge system, coaxial cables without dielectric insulator were developed, with a small cable capacitance temperature coefficient of the impedance. This pressure measurement system has a sensitivity of dP/P˜5×10-10 and a long-term stability of dP/P˜2.4×10-9 over 18 h. This is especially useful for measurements such as electric and magnetic susceptibility measurements in magnetic fields at low temperatures requiring a high precision.
Mears, R P; Klein, A C; Cromwell, H C
2006-08-11
Medial prefrontal cortex is a crucial region involved in inhibitory processes. Damage to the medial prefrontal cortex can lead to loss of normal inhibitory control over motor, sensory, emotional and cognitive functions. The goal of the present study was to examine the basic properties of inhibitory gating in this brain region in rats. Inhibitory gating has recently been proposed as a neurophysiological assay for sensory filters in higher brain regions that potentially enable or disable information throughput. This perspective has important clinical relevance due to the findings that gating is dramatically impaired in individuals with emotional and cognitive impairments (i.e. schizophrenia). We used the standard inhibitory gating two-tone paradigm with a 500 ms interval between tones and a 10 s interval between tone pairs. We recorded both single unit and local field potentials from chronic microwire arrays implanted in the medial prefrontal cortex. We investigated short-term (within session) and long-term (between session) variability of auditory gating and additionally examined how altering the interval between the tones influenced the potency of the inhibition. The local field potentials displayed greater variability with a reduction in the amplitudes of the tone responses over both the short and long-term time windows. The decrease across sessions was most intense for the second tone response (test tone) leading to a more robust gating (lower T/C ratio). Surprisingly, single unit responses of different varieties retained similar levels of auditory responsiveness and inhibition in both the short and long-term analysis. Neural inhibition decreased monotonically related to the increase in intertone interval. This change in gating was most consistent in the local field potentials. Subsets of single unit responses did not show the lack of inhibition even for the longer intertone intervals tested (4 s interval). These findings support the idea that the medial prefrontal cortex is an important site where early inhibitory functions reside and potentially mediate psychological processes.
Long-term health outcomes of youth sports injuries.
Maffulli, N; Longo, U G; Gougoulias, N; Loppini, M; Denaro, V
2010-01-01
Injuries can counter the beneficial effects of sports participation at a young age if a child or adolescent is unable to continue to participate because of residual effects of injury. This paper reviews current knowledge in the field of long-term health outcomes of youth sports injuries to evaluate the evidence regarding children dropping out of sport due to injury, physeal injuries and growth disturbance, studies of injuries affecting the spine and knee of young and former athletes and surgical outcome of anterior cruciate ligament (ACL) reconstruction in children. Studies of dropping out of sport due to injury are limited primarily to gymnasts and implicate such injuries as ACL rupture and osteochondritis dissecans of the elbow joint in the early retirement of young athletes. Although most physeal injuries resolve with treatment and rest, there is evidence of disturbed physeal growth as a result of injury. Radiological findings implicate the effects of intense physical loading and injury in the development of spinal pathology and back pain during the growth of youth athletes; however, long-term effects are unclear. Follow-up studies of young athletes and adults indicate a high risk of osteoarthritis after meniscus or ACL injury. Prospective cohort studies with a follow-up into adulthood are needed to clarify the long-term health outcomes of youth sports injuries. Important to this research is meticulous documentation of injuries on injury report forms that include age-appropriate designations of the type of injury and accurate determination of exposure-based injury rates.
Qing, Guoping; Zhang, Shaodan; Wang, Huaizhou; Wang, Tao; Wang, Shuhua; Chen, Hong; Wang, Hua; Wang, Ningli
2014-07-01
To evaluate the long-term efficacy of laser peripheral iridotomy (LPI) in preventing deterioration in eyes with pigment dispersion syndrome (PDS). A cohort study. Nineteen patients with PDS were treated with LPI and followed up periodically in Beijing Tongren Eye Center from May 2006 to April 2007. One eye of each patient was chosen randomly for the study. Main investigating items included iris configuration, intraocular pressure (IOP), anterior chamber pigmentation, and visual field analysis. The average follow-up period was (6.5 ± 0.3) years. A paired sample t test was used to determine whether there is a significant difference between average values of pre- and post-LPI IOP and mean deviation of Humphrey visual field analysis in these PDS eyes. The average age of the 19 patients were (35.8 ± 7.1) years on admission. The initial IOP of the 19 eyes was (24.7 ± 2.2) mmHg (1 mmHg = 0.133 kPa) before LPI. The mean deviation (MD) of Humphrey visual field analysis (VFA) were (-1.82 ± 1.26) dB (-4.34--0.28 dB) . All 19 eyes had concave iris and heavy trabecular pigmentation. The iris became flat in all PDS eyes after the laser treatment. At the last follow-up visit, the average IOP was 14.8 ± 2.0 (12-20) mmHg, which was statistically lower than that of baseline (t = 11.49, P < 0.01) . Extent of trabecular pigmentation reduced obviously in 16 eyes. No deterioration or new visual field defect was detected in any of the PDS eyes. MD of the last VFA was -1.79 ± 1.21 (-4.39--0.21 dB) . There was no statistical difference between MD of the last VFA and baseline (t = -0.26, P = 0.798). The long-term follow-up results showed that LPI prevents progression effectively in eyes with PDS.
Geoelectric monitoring at the Boulder magnetic observatory
Blum, Cletus; White, Tim; Sauter, Edward A.; Stewart, Duff; Bedrosian, Paul A.; Love, Jeffrey J.
2017-01-01
Despite its importance to a range of applied and fundamental studies, and obvious parallels to a robust network of magnetic-field observatories, long-term geoelectric field monitoring is rarely performed. The installation of a new geoelectric monitoring system at the Boulder magnetic observatory of the US Geological Survey is summarized. Data from the system are expected, among other things, to be used for testing and validating algorithms for mapping North American geoelectric fields. An example time series of recorded electric and magnetic fields during a modest magnetic storm is presented. Based on our experience, we additionally present operational aspects of a successful geoelectric field monitoring system.
Phantom energy mediates a long-range repulsive force.
Amendola, Luca
2004-10-29
Scalar field models with nonstandard kinetic terms have been proposed in the context of k inflation, of Born-Infeld Lagrangians, of phantom energy and, more in general, of low-energy string theory. In general, scalar fields are expected to couple to matter inducing a new interaction. In this Letter I derive the cosmological perturbation equations and the Yukawa correction to gravity for such general models. I find three interesting results: first, when the field behaves as phantom energy (equation of state less than -1), then the coupling strength is negative, inducing a long-range repulsive force; second, the dark-energy field might cluster on astrophysical scales; third, applying the formalism to a Brans-Dicke theory with a general kinetic term it is shown that its Newtonian effects depend on a single parameter that generalizes the Brans-Dicke constant.
Reconsolidation of drug memories
Sorg, Barbara A.
2012-01-01
Persistent, unwanted memories are believed to be key contributors to drug addiction and the chronic relapse problem over the lifetime of the addict. Contrary to the long-held idea that memories are static and fixed, new studies in the last decade have shown that memories are dynamic and changeable. However, they are changeable only under specific conditions. When a memory is retrieved (reactivated), it becomes labile for a period of minutes to hours and then is reconsolidated to maintain long-term memory. Recent findings indicate that even well-established long-term memories may be susceptible to disruption by interfering with reconsolidation through delivery of certain amnestic agents during memory retrieval. Here I review the growing literature on memory reconsolidation in animal models of addiction, including sensitization, conditioned place preference and self-administration. I also discuss (a) several issues that need to be considered in interpreting the findings from reconsolidation studies and (b) future challenges and directions for memory reconsolidation studies in the field of addiction. The findings indicate promise for using this approach as a therapy for disrupting the long-lasting memories that can trigger relapse. PMID:22342780
Cohen, Eyal; Yatziv, Yossi; Leibovitch, Igal; Kesler, Anat; Cnaan, Ran Ben; Klein, Ainat; Goldenberg, Dafna; Habot-Wilner, Zohar
2016-07-08
Filler injection for face augmentation is a common cosmetic procedure in the last decades, in our case report we describe long-term outcomes of a devastating complication of ophthalmic artery emboli following Calcium Hydroxylapatite filler injection to the nose bridge. A healthy 24-year-old women received a Calcium Hydroxylapatite filler injection to her nose bridge for the correction of nose asymmetry 8 years post rhinoplasty. She developed sudden right eye ocular pain and visual disturbances. Visual acuity was 20/20 in both eyes and visual field in the right eye showed inferior arch with fixation sparing and supero-temporal central scotoma. Examination revealed marked periorbital edema and hematoma, ptosis, ocular movements limitation, an infero-temporal branch retinal artery occlusion and multiple choroidal emboli. Eighteen months post initial presentation ptosis and eye movements returned normal and choroidal emboli absorbed almost completely. However, visual acuity declined to 20/60, visual field showed severe progressive deterioration with a central and supero-nasal field remnant and the optic disc became pallor. Cosmetic injection of calcium hydroxylapatite to the nose bridge can result in arterial emboli to the ophthalmic system with optic nerve, retinal and choroidal involvement causing long term severe visual acuity and visual field impairment.
Cell phones and brain tumors: a review including the long-term epidemiologic data.
Khurana, Vini G; Teo, Charles; Kundi, Michael; Hardell, Lennart; Carlberg, Michael
2009-09-01
The debate regarding the health effects of low-intensity electromagnetic radiation from sources such as power lines, base stations, and cell phones has recently been reignited. In the present review, the authors attempt to address the following question: is there epidemiologic evidence for an association between long-term cell phone usage and the risk of developing a brain tumor? Included with this meta-analysis of the long-term epidemiologic data are a brief overview of cell phone technology and discussion of laboratory data, biological mechanisms, and brain tumor incidence. In order to be included in the present meta-analysis, studies were required to have met all of the following criteria: (i) publication in a peer-reviewed journal; (ii) inclusion of participants using cell phones for > or = 10 years (ie, minimum 10-year "latency"); and (iii) incorporation of a "laterality" analysis of long-term users (ie, analysis of the side of the brain tumor relative to the side of the head preferred for cell phone usage). This is a meta-analysis incorporating all 11 long-term epidemiologic studies in this field. The results indicate that using a cell phone for > or = 10 years approximately doubles the risk of being diagnosed with a brain tumor on the same ("ipsilateral") side of the head as that preferred for cell phone use. The data achieve statistical significance for glioma and acoustic neuroma but not for meningioma. The authors conclude that there is adequate epidemiologic evidence to suggest a link between prolonged cell phone usage and the development of an ipsilateral brain tumor.
Yuan, Fang; Li, Yong; Li, Fen-hua; Sun, Guo-jun; Han, Min; Zhang, Hai-yan; Ji, Zhong; Wu, Chen-yu
2016-01-01
To reveal the effects of different fertilization regimes on weed communities in wheat fields under a rice-wheat rotation system, a survey was conducted before wheat harvest in 2014 after a 4-year long-term recurrent fertilization scheme. Weed species types, density, height and diversity index under different fertilization and straw-returning schemes in wheat fields were studied and complemented with a canonical correspondence analysis on weed community distribution and soil nutrient factors. Twenty weed species were recorded among 36 wheat fields belonging to 19 genera and 11 families. Beckmannia syzigachne, Hemistepta lyrata, Malachium aquaticum and Cnidium monnieri were widely distributed throughout the sampled area. Long-term fertilization appeared to reduce weed species richness and density, particularly for broadleaf weeds, but increased weed height. Diversity and evenness indices of weed communities were lower and dominance indices were higher in fields where chemical fertilizers were applied alone or combined with organic fertilizers, especially, where organic-inorganic compound fertilizer was used, in which it readily caused the outbreak of a dominant species and severe damage. Conversely, diversity and evenness indices of weed communities were higher and dominance indices were lower when the straw was returned to the field combined with chemical or organic fertilizers, in which weed community structures were complex and stable with lower weed density. Under these conditions weeds only caused slight reduction of wheat growth.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marvy, A.; Lioure, A; Heriard-Dubreuil, G.
2003-02-24
As part of the work scope set in the French law on high level long lived waste R&D passed in 1991, CEA is conducting a research program to establish the scientific basis and assess the feasibility of long term storage as an option for the safe management of nuclear waste for periods as long as centuries. This goal is a significant departure from the current industrial practice where storage facilities are usually built to last only a few decades. From a technical viewpoint such an extension in time seems feasible provided care and maintenance is exercised. Considering such long periodsmore » of time, the risk for Society of loosing oversight and control of such a facility is real, which triggers the question of whether and how long term storage safety can be actually achieved. Therefore CEA commissioned a study (1) in which MUTADIS Consultants (2) and CEPN (3) were both involved. The case study looks into several past and actual human enterprises conducted over significant periods o f time, one of them dating back to the end of the 18th century, and all identified out of the nuclear field. Then-prevailing societal behavior and organizational structures are screened out to show how they were or are still able to cope with similar oversight and control goals. As a result, the study group formulated a set of performance criteria relating to issues like responsibility, securing funds, legal and legislative implications, economic sustainable development, all being areas which are not traditionally considered as far as technical studies are concerned. These criteria can be most useful from the design stage onward, first in an attempt to define the facility construction and operating guiding principles, and thereafter to substantiate the safety case for long term storage and get geared to the public dialogue on that undertaking should it become a reality.« less
Zhang, Tao; Liu, Hongbin; Luo, Jiafa; Wang, Hongyuan; Zhai, Limei; Geng, Yucong; Zhang, Yitao; Li, Jungai; Lei, Qiuliang; Bashir, Muhammad Amjad; Wu, Shuxia; Lindsey, Stuart
2018-08-15
The impacts of manure application on soil ammonia (NH 3 ) volatilization and greenhouse gas (GHG) emissions are of interest for both agronomic and environmental reasons. However, how the swine manure addition affects greenhouse gas and N emissions in North China Plain wheat fields is still unknown. A long-term fertilization experiment was carried out on a maize-wheat rotation system in Northern China (Zea mays L-Triticum aestivum L.) from 1990 to 2017. The experiment included four treatments: (1) No fertilizer (CK), (2) single application of chemical fertilizers (NPK), (3) NPK plus 22.5t/ha swine manure (NPKM), (4) NPK plus 33.7t/ha swine manure (NPKM+). A short-term fertilization experiment was conducted from 2016 to 2017 using the same treatments in a field that had been abandoned for decades. The emissions of NH 3 and GHGs were measured during the wheat season from 2016 to 2017. Results showed that after long-term fertilization the wheat yields for NPKM treatment were 7105kg/ha, which were higher than NPK (3880kg/ha) and NPKM+ treatments (5518kg/ha). The wheat yields were similar after short-term fertilization (6098-6887kg/ha). The NH 3 -N emission factors (EF amm ) for NPKM and NPKM+ treatments (1.1 and 1.1-1.4%, respectively) were lower than NPK treatment (2.2%) in both the long and short-term fertilization treatments. In the long- and short-term experiments the nitrous oxide (N 2 O) emission factors (EF nit ) for NPKM+ treatment were 4.2% and 3.7%, respectively, which were higher than for the NPK treatment (3.5% and 2.5%, respectively) and the NPKM treatment (3.6% and 2.2%, respectively). In addition, under long and short-term fertilization, the greenhouse gas intensities for the NPKM+ treatment were 33.7 and 27.0kg CO 2 -eq/kg yield, respectively, which were higher than for the NPKM treatment (22.8 and 21.1kg CO 2 -eq/kg yield, respectively). These results imply that excessive swine manure application does not increase yield but increases GHG emissions. Copyright © 2018 Elsevier B.V. All rights reserved.
Blaze, Jennifer; Roth, Tania L.
2015-01-01
While it is well-known that stress during development and adulthood can confer long-term neurobiological and behavioral consequences, investigators have only recently begun to assess epigenetic modifications associated with these consequences. In this review, we highlight clinical research and work with animal models that provide evidence of the impact of stressful experiences either during the perinatal period or adulthood on DNA methylation and behavior. Additionally, we explore the more controversial concept of transgenerational inheritance, including that associated with preconception stress experienced by the mother or father. Finally, we discuss challenges associated with the idea of transgenerational epigenetics and for the field of epigenetics in general. PMID:25917771
Weathering of radiocaesium contamination on urban streets, walls and roofs.
Andersson, K G; Roed, J; Fogh, C L
2002-01-01
Recent investigations in Russia have emphasised the significance of dose contributions from contamination on urban streets and roof pavings, and, typically to a lesser extent, walls in the urban environment. The crucial factor determining the magnitude of these contributions is the retention of the contamination by the different types of urban surface. Since the Chernobyl accident, a series of long-term field studies has been carried out on urban streets, walls and roofs, to examine the weathering processes of 137Cs on the various surface types. The derived time-functions are applied to estimate resultant long-term doses to inhabitants of an urban centre. The paper highlights the effect on caesium retention of surface material characteristics.
Zhou, Shuang-Xi; Medlyn, Belinda E.; Prentice, Iain Colin
2016-01-01
Background and Aims Experimental drought is well documented to induce a decline in photosynthetic capacity. However, if given time to acclimate to low water availability, the photosynthetic responses of plants to low soil moisture content may differ from those found in short-term experiments. This study aims to test whether plants acclimate to long-term water stress by modifying the functional relationships between photosynthetic traits and water stress, and whether species of contrasting habitat differ in their degree of acclimation. Methods Three Eucalyptus taxa from xeric and riparian habitats were compared with regard to their gas exchange responses under short- and long-term drought. Photosynthetic parameters were measured after 2 and 4 months of watering treatments, namely field capacity or partial drought. At 4 months, all plants were watered to field capacity, then watering was stopped. Further measurements were made during the subsequent ‘drying-down’, continuing until stomata were closed. Key Results Two months of partial drought consistently reduced assimilation rate, stomatal sensitivity parameters (g1), apparent maximum Rubisco activity (Vcmax′) and maximum electron transport rate (Jmax′). Eucalyptus occidentalis from the xeric habitat showed the smallest decline in Vcmax′ and Jmax′; however, after 4 months, Vcmax′ and Jmax′ had recovered. Species differed in their degree of Vcmax′ acclimation. Eucalyptus occidentalis showed significant acclimation of the pre-dawn leaf water potential at which the Vcmax′ and ‘true’ Vcmax (accounting for mesophyll conductance) declined most steeply during drying-down. Conclusions The findings indicate carbon loss under prolonged drought could be over-estimated without accounting for acclimation. In particular, (1) species from contrasting habitats differed in the magnitude of V′cmax reduction in short-term drought; (2) long-term drought allowed the possibility of acclimation, such that V′cmax reduction was mitigated; (3) xeric species showed a greater degree of V′cmax acclimation; and (4) photosynthetic acclimation involves hydraulic adjustments to reduce water loss while maintaining photosynthesis. PMID:26493470
A field protocol to monitor cavity-nesting birds
J. Dudley; V. Saab
2003-01-01
We developed a field protocol to monitor populations of cavity-nesting birds in burned and unburned coniferous forests of western North America. Standardized field methods are described for implementing long-term monitoring strategies and for conducting field research to evaluate the effects of habitat change on cavity-nesting birds. Key references (but not...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallego-Marcos, Fernando; Sánchez, Rafael; Platero, Gloria
We analyze long-range transport through an ac driven triple quantum dot with a single electron. Resonant transitions between separated and detuned dots are mediated by the exchange of n photons with the time-dependent field. An effective model is proposed in terms of second order (cotunneling) processes which dominate the long-range transport between the edge quantum dots. The ac field renormalizes the inter dot hopping, modifying the level hybridization. It results in a non-trivial behavior of the current with the frequency and amplitude of the external ac field.
Method and Madness: De/Colonising Scholarship and Theatre Research with Participants Labelled Mad
ERIC Educational Resources Information Center
Sutherland, Alexandra
2017-01-01
This article discusses a long-term theatre project that I run with mental health care users and staff in a forensic psychiatric hospital in South Africa. I argue that the values underpinning the project align with those of Mad Studies, a field that is located as an emerging academic discipline within disability studies. The article seeks to…
ERIC Educational Resources Information Center
Heldenbrand, Lois; Simms, Michael S.
2012-01-01
Long-term care is a key public issue that affects all of us in some way at some time of our lives. Nowhere is performance improvement and quality management more imperative. Through an 8-month field study and follow-up case study, we discuss how using an integrated approach to individual leadership development, employee engagement, and customer…
Walter C. Shortle; Jody Jellison; Kevin T. Smith; Jonathan S. Schilling
2014-01-01
Depletion of essential mineral nutrients from the rooting zone of trees in northern forests may reduce health and productivity. Long-term field investigations coupled with detailed laboratory studies enhance understanding of the biological processes and suggest means to address potential threats. One such investigation by the U.S. Department of Agriculture, Forest...
Dausman, Alyssa M.; Langevin, Christian D.
2005-01-01
A study was conducted to evaluate the relation between water-level fluctuations and saltwater intrusion in Broward County, Florida. The objective was achieved through data collection at selected wells in Broward County and through the development of a variable-density ground-water flow model. The numerical model is representative of many locations in Broward County that contain a well field, control structure, canal, the Intracoastal Waterway, and the Atlantic Ocean. The model was used to simulate short-term movement (from tidal fluctuations to monthly changes) and long-term movement (greater than 10 years) of the saltwater interface resulting from changes in rainfall, well-field withdrawals, sea-level rise, and upstream canal stage. The SEAWAT code, which is a combined version of the computer codes, MODFLOW and MT3D, was used to simulate the complex variable-density flow patterns. Model results indicated that the canal, control structure, and sea level have major effects on ground-water flow. For periods greater than 10 years, the upstream canal stage controls the movement and location of the saltwater interface. If upstream canal stage is decreased by 1 foot (0.3048 meter), the saltwater interface takes 50 years to move inland and stabilize. If the upstream canal stage is then increased by 1 foot (0.3048 meter), the saltwater interface takes 90 years to move seaward and stabilize. If sea level rises about 48 centimeters over the next 100 year as predicted, then inland movement of the saltwater interface may cause well-field contamination. For periods less than 10 years, simulation results indicated that a 3-year drought with increased well-field withdrawals probably will not have long-term effects on the position of the saltwater interface in the Biscayne aquifer. The saltwater interface returns to its original position in less than 10 years. Model results, however, indicated that the interface location in the lower part of the surficial aquifer system takes longer than 10 years to recover from a drought. Additionally, rainfall seems to have the greatest effect on saltwater interface movement in areas some distance from canals, but the upstream canal stage has the greatest effect on the movement of the saltwater interface near canals. Field data indicated that saltwater interface movement includes short-term fluctuations caused by tidal fluctuations and long-term seasonal fluctuations. Statistical analyses of daily-averaged data indicated that the saltwater interface moves in response to pumpage, rainfall, and upstream canal stage. In areas near the canal, the saltwater interface is most affected by canal stage because water-management structures control the stage in the upstream part of the canal and allow movement of the saltwater interface. In areas away from the canal, the saltwater interface is most affected by pumpage and rainfall, depending on the location of well fields. Data analyses also revealed that rainfall changes the vertical flow direction in the Biscayne aquifer. Results from the study indicated that upstream canal stage substantially affects the long-term position of the saltwater interface in the surficial aquifer system. The saltwater interface moves faster inland than seaward because of changes in upstream canal stage. For short-term problems, such as drought, the threat of saltwater intrusion in the Biscayne aquifer does not appear to be severe if the well-field withdrawal is increased; however, this conclusion is based on the assumption that well-field withdrawals will decrease once the drought is over. Sea-level rise may be a potential threat to the water supply in Broward County as the saltwater interface moves inland toward well fields.
Global Governance 2025: At a Critical Juncture
2010-09-01
them. Formal institutions remain largely unreformed and Western states probably must shoulder a disproportionate share of “global governance” as...might be in a better position but may still be fiscally constrained if its budgetary shortfalls and long-term debt problems remain unresolved...that undermine both the environment and investment. Reliance on domestic reserves of fossil fuels or long- term access to foreign fields makes
Preparing Tomorrow’s Nursing Home Nurses: The Wisconsin-Long Term Care Clinical Scholars Program
Nolet, Kim; Roberts, Tonya; Gilmore-Bykovskyi, Andrea; Roiland, Rachel; Gullickson, Colleen; Ryther, Brenda; Bowers, Barbara J.
2014-01-01
Preparing future nurses to care for the growing population of older adults has become a national priority. The demand for long term care services is expected to double between 2000 and 2040, yet the field remains stigmatized as an undesirable place for highly-skilled nurses to work. Recent efforts to increase student preparation in geriatrics have been shown to improve student attitudes toward working with older adults and increase knowledge, but long term care settings remain unattractive to students. This paper reports on development, implementation and evaluation of The Wisconsin Long Term Care Clinical Scholars Program, a nursing home internship for baccalaureate nursing students. The program couples a paid nursing home work experience with an evidence-based long term care nursing curriculum. The program increased student preparation and interest in working with older adults and in nursing homes, while concurrently increasing the capacity of nursing homes to provide a positive student experience. PMID:25162659
Tooming, Ene; Merivee, Enno; Must, Anne; Sibul, Ivar; Williams, Ingrid
2014-06-01
Sub-lethal effects of pesticides on behavioural endpoints are poorly studied in carabids (Coleoptera: Carabidae) though changes in behaviour caused by chemical stress may affect populations of these non-targeted beneficial insects. General motor activity and locomotion are inherent in many behavioural patterns, and changes in these activities that result from xenobiotic influence mirror an integrated response of the insect to pesticides. Influence of pyrethroid insecticides over a wide range of sub-lethal doses on the motor activities of carabids still remains unclear. Video tracking of Platynus assimilis showed that brief exposure to alpha-cypermethrin at sub-lethal concentrations ranged from 0.01 to 100 mg L(-1) caused initial short-term (< 2 h) locomotor hyperactivity followed by a long-term (>24 h) locomotor hypo-activity. In addition, significant short- and long-term concentration and time-dependent changes occurred in general motor activity patterns and rates. Conspicuous changes in motor activity of Platynus assimilis beetles treated at alpha-cypermethrin concentrations up to 75,000-fold lower than maximum field recommended concentration (MFRC) suggest that many, basic fitness-related behaviours might be severely injured as well. These changes may negatively affect carabid populations in agro-ecosystems. Long-term hypo-activity could directly contribute to decreased trap captures of carabids frequently observed after insecticide application in the field. © 2013 Society of Chemical Industry.
Xu, Yaqian; Gu, Xiaoyu; Di, Guoqing
2018-06-07
With the rapid development of ultra-high-voltage direct-current (UHVDC) transmission, the strength of environmental static electric field (SEF) around UHVDC transmission lines increased substantially, which has aroused widely public attention on the potential health effects of SEF. In this study, the effect of SEF exposure on learning and memory ability was investigated. Institute of Cancer Research mice were exposed to 56.3 kV/m SEF for a short term (7 days) or long term (49 days). Behaviors in the Morris water maze (MWM) test, hippocampal neurotransmitter contents, and oxidative stress indicators were examined. Results showed that short-term SEF exposure significantly prolonged escape latency and decreased the number of platform-site crossovers, as well as decreased the time spent in the target quadrant in the MWM test. Meanwhile, serotonin level and the ratio of glutamate level to γ-aminobutyric acid level changed significantly. Besides, malondialdehyde content and glutathione peroxidase activity increased significantly, while superoxide dismutase activity decreased significantly. After long-term SEF exposure, all indices above showed no significant differences between the SEF and sham exposure groups. These data indicated that short-term exposure to 56.3 kV/m SEF could cause abnormal neurotransmitter levels and oxidative stress in the hippocampus, which led to the decline in learning and memory ability. Under the condition of long-term exposure, the SEF-induced disturbances in neurotransmitter contents and redox balance were offset by the compensatory responses of mice, and thus, the learning and memory ability returned to normal level. The temporary and reversible decline in learning and memory ability was only a common biological effect of SEF rather than a health hazard.
Navarro, Rosa M; Vercimak, Danika C
2012-01-01
This retrospective data collection study aims to evaluate the responses of patients who have been implanted with a neuromodulation system using a combination of spinal cord stimulation (SCS) and peripheral subcutaneous field stimulation (PSFS) leads for chronic intractable pain. Forty patients with chronic, intractable pain implanted with both SCS and PSFS leads were enrolled in a retrospective data collection study. Pre-implant data (demographics, pain levels, pain location, and medication use) and post-implant data (pain levels, medication use, and device programming reports) were compared to measure short- and long-term improvements in pain for a period of approximately six months. Device system use and parameter data were collected. The majority of patients experienced immediate and short-term pain relief and reduction in oral pain medications as a result of combination SCS/PSFS therapy. The improvements were maintained for some, but not all patients by six months. Patients cycled through multiple programs over follow-up; the use of triangular stimulation was consistent over time, and by six months, patients preferred this program over others. Limitations of the retrospective chart review included missing data and variable follow-up times, and may have made determinations of long-term efficacy difficult. This study demonstrates that combination SCS and PSFS therapy is potentially a beneficial treatment option for reducing pain levels and oral pain medication compared with baseline in previously resistive chronic pain patients. There is a need for further study of this therapy in a greater number of subjects and in a prospective, controlled setting. In the author's general experience, triangular stimulation is very effective for treating isolated low back pain, because it covers larger topographic areas of the lower back than flow or field stimulation. An investigational device exemption study will be necessary for subcutaneous field stimulation indicated for focal isolated pain to be adequately investigated and utilized by physicians in the future. © 2012 International Neuromodulation Society.
Ouyang, Wei; Wu, Yuyang; Hao, Zengchao; Zhang, Qi; Bu, Qingwei; Gao, Xiang
2018-02-01
Soil erosion exhibits special characteristics in the process of agricultural development. Understanding the combined impacts of land use and soil property changes on soil erosion, especially in the area under long-term agricultural cultivations, is vital to watershed agricultural and soil management. This study investigated the temporal-spatial patterns of the soil erosion based on a modified version of Universal Soil Loss Equation (USLE) and conducted a soil erosion contribution analysis. The land use data were interpreted from Landsat series images, and soil properties were obtained from field sampling, laboratory tests and SPAW (Soil-Plant-Atmosphere-Water) model calculations. Over a long period of agricultural development, the average erosion modulus decreased from 187.7tkm -2 a -1 in 1979 to 158.4tkm -2 a -1 in 2014. The land use types were transformed mainly in the reclamation of paddy fields and the shrinking of wetlands on a large scale. Most of the soils were converted to loam from silty or clay loam and the saturated hydraulic conductivity (K s ) of most soil types decreased by 1.11% to 43.6%. The rapidly increasing area of 49.8km 2 of paddy fields together with the moderate decrease of 14.0km 2 of forests, as well as K s values explained 87.4% of the total variance in soil erosion. Although changes in soil physical and water characteristics indicated that soil erosion loads should have become higher, the upsurge in paddy fields played an important role in mitigating soil erosion in this study area. These results demonstrated that land use changes had more significant impacts than soil property changes on soil erosion. This study suggested that rational measures should be taken to extend paddy fields and control the dry land farming. These findings will benefit watershed agricultural targeting and management. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Lyons, Mitchell B.; Phinn, Stuart R.; Roelfsema, Chris M.
2012-07-01
Long term global archives of high-moderate spatial resolution, multi-spectral satellite imagery are now readily accessible, but are not being fully utilised by management agencies due to the lack of appropriate methods to consistently produce accurate and timely management ready information. This work developed an object-based remote sensing approach to map land cover and seagrass distribution in an Australian coastal environment for a 38 year Landsat image time-series archive (1972-2010). Landsat Multi-Spectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) imagery were used without in situ field data input (but still using field knowledge) to produce land and seagrass cover maps every year data were available, resulting in over 60 map products over the 38 year archive. Land cover was mapped annually using vegetation, bare ground, urban and agricultural classes. Seagrass distribution was also mapped annually, and in some years monthly, via horizontal projected foliage cover classes, sand and deep water. Land cover products were validated using aerial photography and seagrass maps were validated with field survey data, producing several measures of accuracy. An average overall accuracy of 65% and 80% was reported for seagrass and land cover products respectively, which is consistent with other studies in the area. This study is the first to show moderate spatial resolution, long term annual changes in land cover and seagrass in an Australian environment, created without the use of in situ data; and only one of a few similar studies globally. The land cover products identify several long term trends; such as significant increases in South East Queensland's urban density and extent, vegetation clearing in rural and rural-residential areas, and inter-annual variation in dry vegetation types in western South East Queensland. The seagrass cover products show that there has been a minimal overall change in seagrass extent, but that seagrass cover level distribution is extremely dynamic; evidenced by large scale migrations of higher seagrass cover levels and several sudden and significant changes in cover level. These mapping products will allow management agencies to build a baseline assessment of their resources, understand past changes and help inform implementation and planning of management policy to address potential future changes.
Contractual Duration and Investment Incentives: Evidence from Large Scale Production Units in China
NASA Astrophysics Data System (ADS)
Li, Fang; Feng, Shuyi; D'Haese, Marijke; Lu, Hualiang; Qu, Futian
2017-04-01
Large Scale Production Units have become important forces in the supply of agricultural commodities and agricultural modernization in China. Contractual duration in farmland transfer to Large Scale Production Units can be considered to reflect land tenure security. Theoretically, long-term tenancy contracts can encourage Large Scale Production Units to increase long-term investments by ensuring land rights stability or favoring access to credit. Using a unique Large Scale Production Units- and plot-level field survey dataset from Jiangsu and Jiangxi Province, this study aims to examine the effect of contractual duration on Large Scale Production Units' soil conservation behaviours. IV method is applied to take into account the endogeneity of contractual duration and unobserved household heterogeneity. Results indicate that farmland transfer contract duration significantly and positively affects land-improving investments. Policies aimed at improving transaction platforms and intermediary organizations in farmland transfer to facilitate Large Scale Production Units to access farmland with long-term tenancy contracts may therefore play an important role in improving soil quality and land productivity.
USDA-ARS?s Scientific Manuscript database
In conventional and most IPM programs, application of insecticides continues to be the most important responsive pest control tactic. For both immediate and long-term optimization and sustainability of insecticide applications, it is paramount to study the factors affecting the performance of insect...
Long-term irrigation affects the dynamics and activity of the wheat rhizosphere microbiome
USDA-ARS?s Scientific Manuscript database
The Inland Pacific Northwest encompasses 1.6 million cropland hectares and is a major wheat-producing area in the western United States. The climate throughout the region is semi-arid, making the availability of water a significant challenge for agriculture. We conducted a three-year field study inv...
Modelling the management of forest ecosystems: Importance of wood decomposition
Juan A. Blanco; Deborah S. Page-Dumroese; Martin F. Jurgensen; Michael P. Curran; Joanne M. Tirocke; Joanna Walitalo
2018-01-01
Scarce and uncertain data on woody debris decomposition rates are available for calibrating forest ecosystem models, owing to the difficulty of their empirical estimations. Using field data from three experimental sites which are part of the North American Long-Term Soil Productivity (LTSP) Study in south-eastern British Columbia (Canada), we developed probability...
Continued support of long-term research - the old rotation
USDA-ARS?s Scientific Manuscript database
The “Old Rotation” experiment (circa 1896) is the oldest continuous cotton study in the world and the third oldest field crops experiment in the U.S. on the same site. The complete history of this experiment was published in 2008 in the centennial issue of Agronomy Journal (C.C. Mitchell, D.P. Delan...
Essays on Applied Microeconomics
ERIC Educational Resources Information Center
Mejia Mantilla, Carolina
2013-01-01
Each chapter of this dissertation studies a different question within the field of Applied Microeconomics. The first chapter examines the mid- and long-term effects of the 1998 Asian Crisis on the educational attainment of Indonesian children ages 6 to 18, at the time of the crisis. The effects are identified as deviations from a linear trend for…
Enhanced Brain Connectivity in Long-term Meditation Practitioners
Luders, Eileen; Clark, Kristi; Narr, Katherine L.; Toga, Arthur W.
2011-01-01
Very little is currently known about the cerebral characteristics that underlie the complex processes of meditation as only a limited number of studies have addressed this topic. Research exploring structural connectivity in meditation practitioners is particularly rare. We thus acquired diffusion tensor imaging (DTI) data of high angular and spatial resolution and used atlas-based tract mapping methods to investigate white matter fiber characteristics in a well-matched sample of long-term meditators and controls (n=54). A broad field mapping approach estimated the fractional anisotropy (FA) for twenty different fiber tracts (i.e., nine tracts in each hemisphere and two inter-hemispheric tracts) that were subsequently used as dependent measures. Results showed pronounced structural connectivity in meditators compared to controls throughout the entire brain within major projection pathways, commissural pathways, and association pathways. The largest group differences were observed within the corticospinal tract, the temporal component of the superior longitudinal fasciculus, and the uncinate fasciculus. While cross-sectional studies represent a good starting point for elucidating possible links between meditation and white matter fiber characteristics, longitudinal studies will be necessary to determine the relative contribution of nature and nurture to enhanced structural connectivity in long-term meditators. PMID:21664467
Yang, Lei; Chen, Qinghua; Lv, Bin; Wu, Tongning
2017-05-01
Long-term evolution (LTE) wireless telecommunication systems are widely used globally, which has raised a concern that exposure to electromagnetic fields (EMF) emitted from LTE devices can change human neural function. To date, few studies have been conducted on the effect of exposure to LTE EMF. Here, we evaluated the changes in electroencephalogram (EEG) due to LTE EMF exposure. An LTE EMF exposure system with a stable power emission, which was equivalent to the maximum emission from an LTE mobile phone, was used to radiate the subjects. Numerical simulations were conducted to ensure that the specific absorption rate in the subject's head was below the safety limits. Exposure to LTE EMF reduced the spectral power and the interhemispheric coherence in the alpha and beta bands of the frontal and temporal brain regions. No significant change was observed in the spectral power and the inter-hemispheric coherence in different timeslots during and after the exposure. These findings also corroborated those of our previous study using functional magnetic resonant imaging.
NASA Astrophysics Data System (ADS)
Seneca, S. M.; Rabideau, A. J.; Bandilla, K.
2010-12-01
Experimental and modeling studies are in progress to evaluate the long-term performance of a permeable treatment wall comprised of zeolite-rich rock for the removal of strontium-90 from groundwater. Multiple column tests were performed at the University at Buffalo and on-site West Valley Environmental Services; columns were supplied with synthetic groundwater referenced to anticipate field conditions and radioactive groundwater on-site WVES. The primary focus in this work is on quantifying the competitive ion exchange among five cations (Na+, K+, Ca2+, Mg2+, and Sr2+); the data obtained from the column studies is used to support the robust estimation of zeolite cation exchange parameters. This research will produce a five-solute cation exchange model describing the removal efficiency of the zeolite, using the various column tests to calibrate and validate the geochemical transport model. The field-scale transport model provides flexibility to explore design parameters and potential variations in groundwater geochemistry to investigate the long-term performance of a full scale treatment wall at the Western New York nuclear facility.
NASA Astrophysics Data System (ADS)
Longo, M.; Keller, M.; Scaranello, M. A., Sr.; dos-Santos, M. N.; Xu, Y.; Huang, M.; Morton, D. C.
2017-12-01
Logging and understory fires are major drivers of tropical forest degradation, reducing carbon stocks and changing forest structure, composition, and dynamics. In contrast to deforested areas, sites that are disturbed by logging and fires retain some, albeit severely altered, forest structure and function. In this study we simulated selective logging using the Ecosystem Demography Model (ED-2) to investigate the impact of a broad range of logging techniques, harvest intensities, and recurrence cycles on the long-term dynamics of Amazon forests, including the magnitude and duration of changes in forest flammability following timber extraction. Model results were evaluated using eddy covariance towers at logged sites at the Tapajos National Forest in Brazil and data on long-term dynamics reported in the literature. ED-2 is able to reproduce both the fast (< 5yr) recovery of water, energy fluxes compared to flux tower, and the typical, field-observed, decadal time scales for biomass recovery when no additional logging occurs. Preliminary results using the original ED-2 fire model show that canopy cover loss of forests under high-intensity, conventional logging cause sufficient drying to support more intense fires. These results indicate that under intense degradation, forests may shift to novel disturbance regimes, severely reducing carbon stocks, and inducing long-term changes in forest structure and composition from recurrent fires.
Massonnet, D.; Holzer, T.; Vadon, H.
1997-01-01
Interferometric combination of pairs of synthetic aperture radar (SAR) images acquired by the ERS-1 satellite maps the deformation field associated with the activity of the East Mesa geothermal plant, located in southern California. SAR interferometry is applied to this flat area without the need of a digital terrain model. Several combinations are used to ascertain the nature of the phenomenon. Short term interferograms reveal surface phase changes on agricultural fields similar to what had been observed previously with SEASAT radar data. Long term (2 years) interferograms allow the study of land subsidence and improve prior knowledge of the displacement field, and agree with existing, sparse levelling data. This example illustrates the power of the interferometric technique for deriving accurate industrial intelligence as well as its potential for legal action, in cases involving environmental damages. Copyright 1997 by the American Geophysical Union.
Development of the NHM-LETKF regional reanalysis system assimilating conventional observations only
NASA Astrophysics Data System (ADS)
Fukui, S.; Iwasaki, T.; Saito, K. K.; Seko, H.; Kunii, M.
2016-12-01
The information about long-term high-resolution atmospheric fields is very useful for studying meso-scale responses to climate change or analyzing extreme events. We are developing a NHM-LETKF (the local ensemble transform Kalman filter with the nonhydrostatic model of the Japan Meteorological Agency (JMA)) regional reanalysis system assimilating only conventional observations that are available over about 60 years such as surface observations at observatories and upper air observations with radiosondes. The domain covers Japan and its surroundings. Before the long-term reanalysis is performed, an experiment using the system was conducted over August in 2014 in order to identify effectiveness and problems of the regional reanalysis system. In this study, we investigated the six-hour accumulated precipitations obtained by integration from the analysis fields. The reproduced precipitation was compared with the JMA's Radar/Rain-gauge Analyzed Precipitation data over Japan islands and the precipitation of JRA-55, which is used as lateral boundary conditions. The comparisons reveal the underestimation of the precipitation in the regional reanalysis. The underestimation is improved by extending the forecast time. In the regional reanalysis system, the analysis fields are derived using the ensemble mean fields, where the conflicting components among ensemble members are filtered out. Therefore, it is important to tune the inflation factor and lateral boundary perturbations not to smooth the analysis fields excessively and to consider more time to spin-up the fields. In the extended run, the underestimation still remains. This implies that the underestimation is attributed to the forecast model itself as well as the analysis scheme.
Herler, Jürgen; Dirnwöber, Markus
2011-10-31
Estimating the impacts of global and local threats on coral reefs requires monitoring reef health and measuring coral growth and calcification rates at different time scales. This has traditionally been mostly performed in short-term experimental studies in which coral fragments were grown in the laboratory or in the field but measured ex situ. Practical techniques in which growth and measurements are performed over the long term in situ are rare. Apart from photographic approaches, weight increment measurements have also been applied. Past buoyant weight measurements under water involved a complicated and little-used apparatus. We introduce a new method that combines previous field and laboratory techniques to measure the buoyant weight of entire, transplanted corals under water. This method uses an electronic balance fitted into an acrylic glass underwater housing and placed atop of an acrylic glass cube. Within this cube, corals transplanted onto artificial bases can be attached to the balance and weighed at predetermined intervals while they continue growth in the field. We also provide a set of simple equations for the volume and weight determinations required to calculate net growth rates. The new technique is highly accurate: low error of weight determinations due to variation of coral density (< 0.08%) and low standard error (< 0.01%) for repeated measurements of the same corals. We outline a transplantation technique for properly preparing corals for such long-term in situ experiments and measurements.
Flight deck magnetic fields in commercial aircraft.
Nicholas, J S; Butler, G C; Lackland, D T; Hood, W C; Hoel, D G; Mohr, L C
2000-11-01
Airline pilots are exposed to magnetic fields generated by the aircraft's electrical system. The objectives of this study were (1) to directly measure flight deck magnetic fields in terms of personal exposure to the pilots when flying on different aircraft types over a 75-hour flight-duty month, and (2) to compare magnetic field exposures across flight deck types and job titles. Measurements were taken using personal dosimeters carried by either the Captain or the First Officer on Boeing 737/200, Boeing 747/400, Boeing 767/300ER, and Airbus 320 aircraft. Approximately 1,008 block hours were recorded at a sampling frequency of 3 seconds. Total block time exposure to the pilots ranged from a harmonic geometric mean of 6.7 milliGauss (mG) for the Boeing 767/300ER to 12.7 mG for the Boeing 737/200. Measured flight deck magnetic field levels were substantially above the 0.8-1 mG level typically found in the home or office and suggest the need for further study to evaluate potential health effects of long-term exposure. Copyright 2000 Wiley-Liss, Inc.
Andersson, Arne; Bohman, Sara; Borg, L. A. Håkan; Paulsson, Johan F.; Schultz, Sebastian W.; Westermark, Gunilla T.; Westermark, Per
2008-01-01
Following the encouraging report of the Edmonton group, there was a rejuvenation of the islet transplantation field. After that, more pessimistic views spread when long-term results of the clinical outcome were published. A progressive loss of the β-cell function meant that almost all patients were back on insulin therapy after 5 years. More than 10 years ago, we demonstrated that amyloid deposits rapidly formed in human islets and in mouse islets transgenic for human IAPP when grafted into nude mice. It is, therefore, conceivable to consider amyloid formation as one potential candidate for the long-term failure. The present paper reviews attempts in our laboratories to elucidate the dynamics of and mechanisms behind the formation of amyloid in transplanted islets with special emphasis on the impact of long-term hyperglycemia. PMID:19277203
Environmental modeling and recognition for an autonomous land vehicle
NASA Technical Reports Server (NTRS)
Lawton, D. T.; Levitt, T. S.; Mcconnell, C. C.; Nelson, P. C.
1987-01-01
An architecture for object modeling and recognition for an autonomous land vehicle is presented. Examples of objects of interest include terrain features, fields, roads, horizon features, trees, etc. The architecture is organized around a set of data bases for generic object models and perceptual structures, temporary memory for the instantiation of object and relational hypotheses, and a long term memory for storing stable hypotheses that are affixed to the terrain representation. Multiple inference processes operate over these databases. Researchers describe these particular components: the perceptual structure database, the grouping processes that operate over this, schemas, and the long term terrain database. A processing example that matches predictions from the long term terrain model to imagery, extracts significant perceptual structures for consideration as potential landmarks, and extracts a relational structure to update the long term terrain database is given.
The measurement procedure in the SEMONT monitoring system.
Djuric, Nikola; Kljajic, Dragan; Kasas-Lazetic, Karolina; Bajovic, Vera
2014-03-01
The measurement procedure of the open area in situ electric field strength is presented, acquiring the real field data for testing of the Serbian electromagnetic field monitoring network (SEMONT) and its Internet portal. The SEMONT monitoring system introduces an advanced approach of wireless sensor network utilization for the continuous supervision of overall and cumulative level of electromagnetic field over the observed area. The aim of the SEMONT system is to become a useful tool for the national and municipal agencies for the environmental protection, regarding the electromagnetic pollution monitoring and the exposure assessment of the general population. Considering the public concern on the potentially harmful effects of the long-term exposure to electromagnetic radiation, as well as the public transparency principle that is incorporated into the Serbian law on non-ionizing radiation protection, the SEMONT monitoring system is designed for the long-term continuous monitoring, presenting real-time measurement results, and corresponding exposure assessment over the public Internet network.
Long Term, Operational Monitoring Of Enhanced Oil Recovery In Harsh Environments With INSAR
NASA Astrophysics Data System (ADS)
Sato, S.; Henschel, M. D.
2012-01-01
Since 2004, MDA GSI has provided ground deformation measurements for an oil field in northern Alberta, Canada using InSAR technology. During this period, the monitoring has reliably shown the slow rise of the oil field due to enhanced oil recovery operations. The InSAR monitoring solution is essentially based on the observation of point and point-like targets in the field. Ground conditions in the area are almost continuously changing (in their reflectivity characteristics) making it difficult to ob- serve coherent patterns from the ground. The extended duration of the oil operations has allowed us to continue InSAR monitoring and transition from RADARSAT-1 to RADARSAT-2. With RADARSAT-2 and the enhancement of the satellite resolution capability has provided more targets of opportunity as identified by a differential coherence method. This poster provides an overview of the long term monitoring of the oil field in northern Alberta, Canada.
Monte Carlo simulations for generic granite repository studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chu, Shaoping; Lee, Joon H; Wang, Yifeng
In a collaborative study between Los Alamos National Laboratory (LANL) and Sandia National Laboratories (SNL) for the DOE-NE Office of Fuel Cycle Technologies Used Fuel Disposition (UFD) Campaign project, we have conducted preliminary system-level analyses to support the development of a long-term strategy for geologic disposal of high-level radioactive waste. A general modeling framework consisting of a near- and a far-field submodel for a granite GDSE was developed. A representative far-field transport model for a generic granite repository was merged with an integrated systems (GoldSim) near-field model. Integrated Monte Carlo model runs with the combined near- and farfield transport modelsmore » were performed, and the parameter sensitivities were evaluated for the combined system. In addition, a sub-set of radionuclides that are potentially important to repository performance were identified and evaluated for a series of model runs. The analyses were conducted with different waste inventory scenarios. Analyses were also conducted for different repository radionuelide release scenarios. While the results to date are for a generic granite repository, the work establishes the method to be used in the future to provide guidance on the development of strategy for long-term disposal of high-level radioactive waste in a granite repository.« less
Doors for memory: A searchable database.
Baddeley, Alan D; Hitch, Graham J; Quinlan, Philip T; Bowes, Lindsey; Stone, Rob
2016-11-01
The study of human long-term memory has for over 50 years been dominated by research on words. This is partly due to lack of suitable nonverbal materials. Experience in developing a clinical test suggested that door scenes can provide an ecologically relevant and sensitive alternative to the faces and geometrical figures traditionally used to study visual memory. In pursuing this line of research, we have accumulated over 2000 door scenes providing a database that is categorized on a range of variables including building type, colour, age, condition, glazing, and a range of other physical characteristics. We describe an illustrative study of recognition memory for 100 doors tested by yes/no, two-alternative, or four-alternative forced-choice paradigms. These stimuli, together with the full categorized database, are available through a dedicated website. We suggest that door scenes provide an ecologically relevant and participant-friendly source of material for studying the comparatively neglected field of visual long-term memory.
Nüchtern, Elisabeth; Gansweid, Barbara; Gerber, Hans; von Mittelstaedt, Gert
2017-01-01
Objective: By the "Second Bill to Strengthen Long-Term Care", a new concept of long-term care dependency will be introduced, valid from 2017. Long-term care dependency according to Social Code XI will be defined covering more aspects than today. Therefore, the working group "Nursing Care" of the division "Social Medicine in Practice and Rehabilitation" in the German Society for Social Medicine and Prevention presents their results after working on the social medicine perspective of the definition and prevention of long-term care dependency. Methods: Both the definition and strategies to prevent long-term care dependency are systematically taken into consideration from the point of view of social medicine on the basis of the International Classification of Functioning, Disability and Health (ICF), as long-term care dependency means a defined condition of disability. Results: Both the current and the new concept of long-term care dependency focus activity limitations. The perspective of social medicine considers the interactions of health condition, its effects on daily activities and personal as well as environmental factors. From this point of view approaches for social benefits concerning prevention and rehabilitation can be identified systematically so as to work against the development and progression of long-term care dependency. The reference to the ICF can facilitate the communication between different professions. The new "graduation" of long-term care dependency would allow an international "translation" referring to the ICF. Conclusion: Experts from the field of social medicine as well as those of nursing care, care-givers and nursing researchers have in common the objective that persons in need of nursing care can participate in as many aspects of life of importance to them in an autonomous and self-determined way. The point of view of social medicine on long-term care dependency is fundamental for all occupational groups that are involved and for their successful cooperation. © Georg Thieme Verlag KG Stuttgart · New York.
NASA Astrophysics Data System (ADS)
Erdal, Daniel; Cirpka, Olaf A.
2017-04-01
Regional groundwater flow strongly depends on groundwater recharge and hydraulic conductivity. While conductivity is a spatially variable field, recharge can vary in both space and time. None of the two fields can be reliably observed on larger scales, and their estimation from other sparse data sets is an open topic. Further, common hydraulic-head observations may not suffice to constrain both fields simultaneously. In the current work we use the Ensemble Kalman filter to estimate spatially variable conductivity, spatiotemporally variable recharge and porosity for a synthetic phreatic aquifer. We use transient hydraulic-head and one spatially distributed set of environmental tracer observations to constrain the estimation. As environmental tracers generally reside for a long time in an aquifer, they require long simulation times and carries a long memory that makes them highly unsuitable for use in a sequential framework. Therefore, in this work we use the environmental tracer information to precondition the initial ensemble of recharge and conductivities, before starting the sequential filter. Thereby, we aim at improving the performance of the sequential filter by limiting the range of the recharge to values similar to the long-term annual recharge means and by creating an initial ensemble of conductivities that show similar pattern and values to the true field. The sequential filter is then used to further improve the parameters and to estimate the short term temporal behavior as well as the temporally evolving head field needed for short term predictions within the aquifer. For a virtual reality covering a subsection of the river Neckar it is shown that the use of environmental tracers can improve the performance of the filter. Results using the EnKF with and without this preconditioned initial ensemble are evaluated and discussed.
Long-term Variability of Beach Cusps
NASA Astrophysics Data System (ADS)
Pianca, C.; Holman, R. A.; Siegle, E.
2016-02-01
The most curious morphological features observed on beaches are the cusps. Due to their rhythmic spacing, beach cusps have attracted many observers and many, often contradictory, theories as to their form. Moreover, most of the research about beach cusps has focused on their formation. Few had available long time series to study such things as the variability of alongshore and cross-shore position and spacing on the cusp field, the presence, longevity and interactions between higher and lower sets of cusps, and the processes by which cusp fields extend, shrink or change length scale. The purpose of this work is to use long-term data sets of video images from two study sites, an intermediate (Duck, USA, 26 years) and a reflective beach (Massaguaçu, Brazil, 3 years), to investigate the temporal and spatial changes of cusps conditions. Time-evolving shoreline data were first extracted using an algorithm called ASLIM (Pianca et al 2015). Cusps were then identified based on the band-passed variability of time exposure image data about this shoreline as a function of elevation relative to MSL. The identified beaches cusps will be analyzed for cusp spacing, positions (upper or lower cusps), alongshore variability, merging events, percentage of cusp events, patterns of the events and time scales of variability. Finally, the relationship of these characteristics to environmental conditions (wave, tides, beach conditions) will be studied.
NASA Astrophysics Data System (ADS)
Alonso, A.; Munoz-Carpena, R.; Kaplan, D. A.
2017-12-01
Wetland ecosystem structure and function are primarily governed by water regime. Characterizing past and current wetland hydrology is thus crucial for identifying the drivers of long-term wetland degradation. Critically, a lack of spatially distributed and long-term data has impeded such characterization in most wetland systems across the world. The publically accessible Moderate Resolution Imaging Spectroradiometer (MODIS) satellite products encode spatial and temporal data for landscape monitoring, but it was unclear whether it could be used to reliably predict the hydric status of wetland due to the mixture of spectral signatures existing within and between such systems. We proposed and tested a methodological framework for the identification of site-specific wetness status spectral identification rule (WSSIR) using two recent technical innovations: affordable, easily deployable field water level sensors to train the WSSIR with supervised learning, and the powerful cloud-based Google Earth Engine (GEE) platform to rapidly access and process the MODIS imagery. This methodological framework was used in a study case of the globally important Palo Verde National Park tropical wetland in Costa Rica. Results showed that a site-specific WISSR could reliably detect wetland wet or dry status (hydroperiod) and capture the temporal variability of the wetness status. We applied it on the 500 m 2000-2016 MODIS Land Surface Reflectance daily product to reconstruct hydroperiod history, hence reaching a temporal resolution rarely matched in remote sensing for environmental studies. The analysis of the resulting long-term, spatially distributed MODIS-derived data, coupled with shorter-term, 15-minute resolution field water level time-series provided new insights into the drivers controlling the spatiotemporal dynamics of hydrology within Palo Verde National Park's degrading wetlands. This new knowledge is critical to make informed restoration and management decisions. Specifically, we identified a significant influence of the surrounding rivers and irrigation district, which emphasised the importance of considering the wetland in the watershed context when elaborating management strategies. The methodological framework can be applied to any other mid- to large-scale wetland systems worldwide.
Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter
2016-01-01
In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.
Mano, Hiroyuki; Tanaka, Yoshinari
2017-12-01
This study examines the spatial difference in genetic variation for tolerance to a pesticide, fenitrothion, in Daphnia galeata at field sites in Lake Kasumigaura, Japan. We estimated genetic values of isofemale lines established from dormant eggs of D. galeata collected from field sampling sites with the toxicant threshold model applied using acute toxicity. We compared genetic values and variances and broad-sense heritability across different sites in the lake. Results showed that the mean tolerance values to fenitrothion did not differ spatially. The variance in genetic value and heritability of fenitrothion tolerance significantly differed between sampling sites, revealing that long-term ecological risk of fenitrothion may differ between local populations in the lake. These results have implications for aquatic toxicology research, suggesting that differences in genetic variation of tolerance to a chemical among local populations must be considered for understanding the long-term ecological risks of the chemical over a large geographic area.
Modeling the Sustainability of a Ceramic Water Filter Intervention
Mellor, Jonathan; Abebe, Lydia; Ehdaie, Beeta; Dillingham, Rebecca; Smith, James
2014-01-01
Ceramic water filters (CWFs) are a point-of-use water treatment technology that has shown promise in preventing early childhood diarrhea (ECD) in resource-limited settings. Despite this promise, some researchers have questioned their ability to reduce ECD incidences over the long term since most effectiveness trials conducted to date are less than one year in duration limiting their ability to assess long-term sustainability factors. Most trials also suffer from lack of blinding making them potentially biased. This study uses an agent-based model (ABM) to explore factors related to the long-term sustainability of CWFs in preventing ECD and was based on a three year longitudinal field study. Factors such as filter user compliance, microbial removal effectiveness, filter cleaning and compliance declines were explored. Modeled results indicate that broadly defined human behaviors like compliance and declining microbial effectiveness due to improper maintenance are primary drivers of the outcome metrics of household drinking water quality and ECD rates. The model predicts that a ceramic filter intervention can reduce ECD incidence amongst under two year old children by 41.3%. However, after three years, the average filter is almost entirely ineffective at reducing ECD incidence due to declining filter microbial removal effectiveness resulting from improper maintenance. The model predicts very low ECD rates are possible if compliance rates are 80-90%, filter log reduction efficiency is 3 or greater and there are minimal long-term compliance declines. Cleaning filters at least once every 4 months makes it more likely to achieve very low ECD rates as does the availability of replacement filters for purchase. These results help to understand the heterogeneity seen in previous intervention-control trials and reemphasize the need for researchers to accurately measure confounding variables and ensure that field trials are at least 2-3 years in duration. In summary, the CWF can be a highly effective tool in the fight against ECD, but every effort should be made by implementing agencies to ensure consistent use and maintenance. PMID:24355289
NASA Astrophysics Data System (ADS)
Richter, D., Jr.; Mobley, M. L.; Billings, S. A.; Markewitz, D.
2016-12-01
At the Calhoun Long-Term Soil-Ecosystem field experiment (1957-present), reforestation of previously cultivated land over fifty years nearly doubled soil organic carbon (SOC) in surface soils (0 to 7.5-cm) but these gains were offset by significant SOC losses in subsoils (35 to 60-cm). Nearly all of the accretions in surface soils amounted to gains in light fraction SOC, whereas losses at depth were associated with silt and clay-sized particles. These changes are documented in the Calhoun Long-Term Soil-Ecosystem (LTSE) study that resampled soil from 16 plots about every five years and archived all soil samples from four soil layers within the upper 60-cm of mineral soil. We combined soil bulk density, density fractionation, stable isotopes, and radioisotopes to explore changes in SOC and soil organic nitrogen (SON) associated with five decades of the growth of a loblolly pine secondary forest. Isotopic signatures showed relatively large accumulations of contemporary forest-derived carbon in surface soils, and no accumulation of forest-derived carbon in subsoils. We interpret results to indicate that land-use change from cotton fields to secondary pine forests drove soil biogeochemical and hydrological changes that enhanced root and microbial activity and SOM decomposition in subsoils. As pine stands matured and are now transitioning to mixed pines and hardwoods, demands on soil organic matter for nutrients to support aboveground growth has eased due to pine mortality, and bulk SOM and SON and their isotopes in subsoils have stabilized. We anticipate major changes in the next fifty years as 1957 pine trees transition to hardwoods. This study emphasizes the importance of long-term experiments and deep soil measurements when characterizing SOC and SON responses to land use change. There is a remarkable paucity of E long-term soil data deeper than 30 cm.
Liu, Shuoyan; Wang, Zhen; Wang, Feng
2016-09-25
Differences in operative procedure and knowledge of esophageal cancer exist among surgeons from different countries and regions. There is controversy in the surgical treatment of esophageal cancer, especially in the extent of lymphadenectomy. Until now, results of the three-field lymphadenectomy and two-field lymphadenectomy are mostly reported by retrospective studies from Japan and China. Three-field lymphadenectomy has been initiated in Fujian Provincial Cancer Hospital since 1990s. After evaluating our database, we found that three-field was superior to two-field lymphadenectomy in terms of long-term survival for patients with upper thoracic esophageal cancer, whereas for those with middle or lower thoracic esophageal cancer, the survival benefit of three-field lymphadenectomy was reduced. Therefore, we propose to perform three-field lymphadenectomy for upper thoracic esophageal cancer. In middle or lower thoracic esophageal cancer, we suggest to perform modified two-field lymphadenectomy in most cases, and three-field lymphadenectomy in selective cases. Video-assisted two-field lymphadenectomy is feasible. Based on the national condition of China, we advise to perform thoracic duct removal only in patients with posterior mediastinal or peri-ductus node metastasis to achieve curative effect.
The nursing home as a home: a field study of residents' daily life in the common living rooms.
Hauge, Solveig; Kristin, Heggen
2008-02-01
This Norwegian-based study investigates how and to what extent the idea of the nursing home as a home has been realized. For the last two decades, Norway, as other Western Country has had an explicit national policy that nursing homes should become more like homes. The research literature indicates that residents in nursing home seem to lack the opportunities to maintain a private sphere. A field study design was conducted. Data were collected in 1999 in two long-term units in a traditional nursing home by using participant observation and interviewing the residents. A phenomenological hermeneutic analysis strategy was used to get an impression of the residents' everyday life. The residents spend most of their time in the common living room. The common living room has an ambiguous boundary between the public and private spheres, unlike the clear boundaries characterizing a home. The relationship among the residents is fragile, and the residents who can, withdraw from the common living room. Despite having single rooms and more home-like interior decoration, the residents in nursing home still have reduced opportunity to develop a private everyday lifestyle. The long-term unit examined in this research had a forced relationship between the residents, and the residents with best health resources systematically withdraw from the common area to control both where and with whom they wish to spend their time. This study lays the foundation for rethinking daily routines in long-term units in nursing homes. One way to realize the idea of the nursing home as a home could be to define the living room as a clear public area and to give the residents a chance to develop a more private lifestyle by alternating between their private rooms and a public common living room.
Performance of low-cost monitors to assess household air pollution.
Curto, A; Donaire-Gonzalez, D; Barrera-Gómez, J; Marshall, J D; Nieuwenhuijsen, M J; Wellenius, G A; Tonne, C
2018-05-01
Exposure to household air pollution is a leading cause of morbidity and mortality globally. However, due to the lack of validated low-cost monitors with long-lasting batteries in indoor environments, most epidemiologic studies use self-reported data or short-term household air pollution assessments as proxies of long-term exposure. We evaluated the performance of three low-cost monitors measuring fine particulate matter (PM 2.5 ) and carbon monoxide (CO) in a wood-combustion experiment conducted in one household of Spain for 5 days (including the co-location of 2 units of HAPEX and 3 units of TZOA-R for PM 2.5 and 3 units of EL-USB-CO for CO; a total of 40 unit-days). We used Spearman correlation (ρ) and Concordance Correlation Coefficient (CCC) to assess accuracy of low-cost monitors versus equivalent research-grade devices. We also conducted a field study in India for 1 week (including HAPEX in 3 households and EL-USB-CO in 4 households; a total of 49 unit-days). Correlation and agreement at 5-min were moderate-high for one unit of HAPEX (ρ = 0.73 / CCC = 0.59), for one unit of TZOA-R (ρ = 0.89 / CCC = 0.62) and for three units of EL-USB-CO (ρ = 0.82-0.89 / CCC = 0.66-0.91) in Spain, although the failure or malfunction rate among low-cost units was high in both settings (60% of unit-days in Spain and 43% in India). Low-cost monitors tested here are not yet ready to replace more established exposure assessment methods in long-term household air pollution epidemiologic studies. More field validation is needed to assess evolving sensors and monitors with application to health studies. Copyright © 2018 Elsevier Inc. All rights reserved.
Occupational Electromagnetic Field Exposures Associated with Sleep Quality: A Cross-Sectional Study
Liu, Hui; Chen, Guangdi; Pan, Yifeng; Chen, Zexin; Jin, Wen; Sun, Chuan; Chen, Chunjing; Dong, Xuanjun; Chen, Kun; Xu, Zhengping; Zhang, Shanchun; Yu, Yunxian
2014-01-01
Background Exposure to electromagnetic field (EMF) emitted by mobile phone and other machineries concerns half the world’s population and raises the problem of their impact on human health. The present study aims to explore the effects of electromagnetic field exposures on sleep quality and sleep duration among workers from electric power plant. Methods A cross-sectional study was conducted in an electric power plant of Zhejiang Province, China. A total of 854 participants were included in the final analysis. The detailed information of participants was obtained by trained investigators using a structured questionnaire, which including socio-demographic characteristics, lifestyle variables, sleep variables and electromagnetic exposures. Physical examination and venous blood collection were also carried out for every study subject. Results After grouping daily occupational electromagnetic exposure into three categories, subjects with long daily exposure time had a significantly higher risk of poor sleep quality in comparison to those with short daily exposure time. The adjusted odds ratios were 1.68 (95%CI: 1.18, 2.39) and 1.57 (95%CI: 1.10, 2.24) across tertiles. Additionally, among the subjects with long-term occupational exposure, the longer daily occupational exposure time apparently increased the risk of poor sleep quality (OR (95%CI): 2.12 (1.23∼3.66) in the second tertile; 1.83 (1.07∼3.15) in the third tertile). There was no significant association of long-term occupational exposure duration, monthly electric fee or years of mobile-phone use with sleep quality or sleep duration. Conclusions The findings showed that daily occupational EMF exposure was positively associated with poor sleep quality. It implies EMF exposure may damage human sleep quality rather than sleep duration. PMID:25340654
Dynamical downscaling of wind fields for wind power applications
NASA Astrophysics Data System (ADS)
Mengelkamp, H.-T.; Huneke, S.; Geyer, J.
2010-09-01
Dynamical downscaling of wind fields for wind power applications H.-T. Mengelkamp*,**, S. Huneke**, J, Geyer** *GKSS Research Center Geesthacht GmbH **anemos Gesellschaft für Umweltmeteorologie mbH Investments in wind power require information on the long-term mean wind potential and its temporal variations on daily to annual and decadal time scales. This information is rarely available at specific wind farm sites. Short-term on-site measurements usually are only performed over a 12 months period. These data have to be set into the long-term perspective through correlation to long-term consistent wind data sets. Preliminary wind information is often asked for to select favourable wind sites over regional and country wide scales. Lack of high-quality wind measurements at weather stations was the motivation to start high resolution wind field simulations The simulations are basically a refinement of global scale reanalysis data by means of high resolution simulations with an atmospheric mesoscale model using high-resolution terrain and land-use data. The 3-dimensional representation of the atmospheric state available every six hours at 2.5 degree resolution over the globe, known as NCAR/NCEP reanalysis data, forms the boundary conditions for continuous simulations with the non-hydrostatic atmospheric mesoscale model MM5. MM5 is nested in itself down to a horizontal resolution of 5 x 5 km². The simulation is performed for different European countries and covers the period 2000 to present and is continuously updated. Model variables are stored every 10 minutes for various heights. We have analysed the wind field primarily. The wind data set is consistent in space and time and provides information on the regional distribution of the long-term mean wind potential, the temporal variability of the wind potential, the vertical variation of the wind potential, and the temperature, and pressure distribution (air density). In the context of wind power these data are used • as an initial estimate of wind and energy potential • for the long-term correlation of wind measurements and turbine production data • to provide wind potential maps on a regional to country wide scale • to provide input data sets for simulation models • to determine the spatial correlation of the wind field in portfolio calculations • to calculate the wind turbine energy loss during prescribed downtimes • to provide information on the temporal variations of the wind and wind turbine energy production The time series of wind speed and wind direction are compared to measurements at offshore and onshore locations.
Temporal variability of spectro-temporal receptive fields in the anesthetized auditory cortex.
Meyer, Arne F; Diepenbrock, Jan-Philipp; Ohl, Frank W; Anemüller, Jörn
2014-01-01
Temporal variability of neuronal response characteristics during sensory stimulation is a ubiquitous phenomenon that may reflect processes such as stimulus-driven adaptation, top-down modulation or spontaneous fluctuations. It poses a challenge to functional characterization methods such as the receptive field, since these often assume stationarity. We propose a novel method for estimation of sensory neurons' receptive fields that extends the classic static linear receptive field model to the time-varying case. Here, the long-term estimate of the static receptive field serves as the mean of a probabilistic prior distribution from which the short-term temporally localized receptive field may deviate stochastically with time-varying standard deviation. The derived corresponding generalized linear model permits robust characterization of temporal variability in receptive field structure also for highly non-Gaussian stimulus ensembles. We computed and analyzed short-term auditory spectro-temporal receptive field (STRF) estimates with characteristic temporal resolution 5-30 s based on model simulations and responses from in total 60 single-unit recordings in anesthetized Mongolian gerbil auditory midbrain and cortex. Stimulation was performed with short (100 ms) overlapping frequency-modulated tones. Results demonstrate identification of time-varying STRFs, with obtained predictive model likelihoods exceeding those from baseline static STRF estimation. Quantitative characterization of STRF variability reveals a higher degree thereof in auditory cortex compared to midbrain. Cluster analysis indicates that significant deviations from the long-term static STRF are brief, but reliably estimated. We hypothesize that the observed variability more likely reflects spontaneous or state-dependent internal fluctuations that interact with stimulus-induced processing, rather than experimental or stimulus design.
Blast Induced Liquefaction of Soils: Laboratory and Field Tests
1988-06-25
characteristics are summarized below and given in Table A.23 in Appendix A.S. 1 . Grain Size Distribution and Grain Shape The physical properties of the sand were...in terms of soil type and void ratio for dynamic tests. -74- Table 4.1. Physical Properties of Monterey No. 0/30 Sand, Bonny Silt and a 50-50 Mixture...Results agree with the experimental observations of peak and long- term porewater pressure responses. The results of our study indicate the following. 1
Investigation of in-vivo skin autofluorescence lifetimes under long-term cw optical excitation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lihachev, A; Ferulova, I; Vasiljeva, K
2014-08-31
The main results obtained during the last five years in the field of laser-excited in-vivo human skin photobleaching effects are presented. The main achievements and results obtained, as well as methods and experimental devices are briefly described. In addition, the impact of long-term 405-nm cw low-power laser excitation on the skin autofluorescence lifetime is experimentally investigated. (laser biophotonics)
Preconcentration for Improved Long-term Monitoring of Contaminants in Groundwater
2014-04-10
Johnson of the US Army Corps of Engineers, Tulsa District (recently retired) provided sites in northeastern Oklahoma for field trials as well as...neighboring wildlife is also a concern. Long-term monitoring of sites undergoing remediation as well as sites that may eventually require cleanup is...Activated charcoal and peroxide cleanup steps offer potential avenues for addressing this problem. The materials may be of value in isotopic analysis of
ERIC Educational Resources Information Center
Fujii, Satoshi; Yamazaki, Yoshihiko; Goto, Jun-Ichi; Fujiwara, Hiroki; Mikoshiba, Katsuhiko
2016-01-01
We investigated the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) activated by preconditioning low-frequency afferent stimulation (LFS) in the subsequent induction of long-term potentiation (LTP) in CA1 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential or the population…
Termiticide field test report: New termiticides & emerging technologies
Bradford M. Kard
2000-01-01
Testing at our nationwide field sites detemines the years-of-effectiveness of currently marketed and potentially new termiticides as treatments to soil under long-term field conditions. Several new termiticide candidates and formulations have been placed in the field during the past four years and will be reported on after they complete five years of testing.
Alves-Conceição, Vanessa; Silva, Daniel Tenório da; Santana, Vanessa Lima de; Santos, Edileide Guimarães Dos; Santos, Lincoln Marques Cavalcante; Lyra, Divaldo Pereira de
2017-07-25
Polypharmacy is a reality in long-term care facilities. However, number of medications used by the patient should not be the only predictor of a complex pharmacotherapy. Although the level of complexity of pharmacotherapy is considered an important factor that may lead to side effects, there are few studies in this field. The aim of this study was to evaluate the complexity of pharmacotherapy in residents of three long-term care facilities. A cross-sectional study was performed to evaluate the complexity of pharmacotherapy using the protocols laid out in the Medication Regimen Complexity Index instrument in three long-term care facilities in northeastern Brazil. As a secondary result, potential drug interactions, potentially inappropriate medications, medication duplication, and polypharmacy were evaluated. After the assessment, the association among these variables and the Medication Regimen Complexity Index was performed. In this study, there was a higher prevalence of women (64.4%) with a high mean age among the study population of 81.8 (±9.7) years. The complexity of pharmacotherapy obtained a mean of 15.1 points (±9.8), with a minimum of 2 and a maximum of 59. The highest levels of complexity were associated with dose frequency, with a mean of 5.5 (±3.6), followed by additional instructions of use averaging 4.9 (±3.7) and by the dosage forms averaging 4.6 (±3.0). The present study evaluated some factors that complicate the pharmacotherapy of geriatric patients. Although polypharmacy was implicated as a factor directly related to complexity, other indicators such as drug interactions, potentially inappropriate medications, and therapeutic duplication can also make the use of pharmacotherapy in such patients more difficult.
Xiong, Wu; Zhao, Qingyun; Xue, Chao; Xun, Weibing; Zhao, Jun; Wu, Huasong; Li, Rong; Shen, Qirong
2016-01-01
Long-term vanilla monocropping often results in the occurrence of vanilla Fusarium wilt disease, seriously affecting its production all over the world. In the present study, vanilla exhibited significantly less Fusarium wilt disease in the soil of a long-term continuously cropped black pepper orchard. The entire fungal communities of bulk and rhizosphere soils between the black pepper-vanilla system (i.e., vanilla cropped in the soil of a continuously cropped black pepper orchard) and vanilla monoculture system were compared through the deep pyrosequencing. The results showed that the black pepper-vanilla system revealed a significantly higher fungal diversity than the vanilla monoculture system in both bulk and rhizosphere soils. The UniFrac-weighted PCoA analysis revealed significant differences in bulk soil fungal community structures between the two cropping systems, and fungal community structures were seriously affected by the vanilla root system. In summary, the black pepper-vanilla system harbored a lower abundance of Fusarium oxysporum in the vanilla rhizosphere soil and increased the putatively plant-beneficial fungal groups such as Trichoderma and Penicillium genus, which could explain the healthy growth of vanilla in the soil of the long-term continuously cropped black pepper field. Thus, cropping vanilla in the soil of continuously cropped black pepper fields for maintaining the vanilla industry is executable and meaningful as an agro-ecological system.
Xiong, Wu; Zhao, Qingyun; Xue, Chao; Xun, Weibing; Zhao, Jun; Wu, Huasong; Li, Rong; Shen, Qirong
2016-01-01
Long-term vanilla monocropping often results in the occurrence of vanilla Fusarium wilt disease, seriously affecting its production all over the world. In the present study, vanilla exhibited significantly less Fusarium wilt disease in the soil of a long-term continuously cropped black pepper orchard. The entire fungal communities of bulk and rhizosphere soils between the black pepper-vanilla system (i.e., vanilla cropped in the soil of a continuously cropped black pepper orchard) and vanilla monoculture system were compared through the deep pyrosequencing. The results showed that the black pepper-vanilla system revealed a significantly higher fungal diversity than the vanilla monoculture system in both bulk and rhizosphere soils. The UniFrac-weighted PCoA analysis revealed significant differences in bulk soil fungal community structures between the two cropping systems, and fungal community structures were seriously affected by the vanilla root system. In summary, the black pepper-vanilla system harbored a lower abundance of Fusarium oxysporum in the vanilla rhizosphere soil and increased the putatively plant-beneficial fungal groups such as Trichoderma and Penicillium genus, which could explain the healthy growth of vanilla in the soil of the long-term continuously cropped black pepper field. Thus, cropping vanilla in the soil of continuously cropped black pepper fields for maintaining the vanilla industry is executable and meaningful as an agro-ecological system. PMID:26903995
Roos, Matthias; Hofmann, Marius; Link, Susanne; Ott, Maria; Balbach, Jochen; Rössler, Ernst; Saalwächter, Kay; Krushelnitsky, Alexey
2015-12-01
Inter-protein interactions in solution affect the auto-correlation function of Brownian tumbling not only in terms of a simple increase of the correlation time, they also lead to the appearance of a weak slow component ("long tail") of the correlation function due to a slowly changing local anisotropy of the microenvironment. The conventional protocol of correlation time estimation from the relaxation rate ratio R1/R2 assumes a single-component tumbling correlation function, and thus can provide incorrect results as soon as the "long tail" is of relevance. This effect, however, has been underestimated in many instances. In this work we present a detailed systematic study of the tumbling correlation function of two proteins, lysozyme and bovine serum albumin, at different concentrations and temperatures using proton field-cycling relaxometry combined with R1ρ and R2 measurements. Unlike high-field NMR relaxation methods, these techniques enable a detailed study of dynamics on a time scale longer than the normal protein tumbling correlation time and, thus, a reliable estimate of the parameters of the "long tail". In this work we analyze the concentration dependence of the intensity and correlation time of the slow component and perform simulations of high-field (15)N NMR relaxation data demonstrating the importance of taking the "long tail" in the analysis into account.
HDAC3 and the Molecular Brake Pad Hypothesis
McQuown, Susan C.; Wood, Marcelo A.
2011-01-01
Successful transcription of specific genes required for long-term memory processes involves the orchestrated effort of not only transcription factors, but also very specific enzymatic protein complexes that modify chromatin structure. Chromatin modification has been identified as a pivotal molecular mechanism underlying certain forms of synaptic plasticity and memory. The best-studied form of chromatin modification in the learning and memory field is histone acetylation, which is regulated by histone acetyltransferases and histone deacetylases (HDACs). HDAC inhibitors have been shown to strongly enhance long-term memory processes, and recent work has aimed to identify contributions of individual HDACs. In this review, we focus on HDAC3 and discuss its recently defined role as a negative regulator of long-term memory formation. HDAC3 is part of a corepressor complex and has direct interactions with class II HDACs that may be important for its molecular and behavioral consequences. And last, we propose the “molecular brake pad” hypothesis of HDAC function. The HDACs and associated corepressor complexes may function in neurons, in part, as “molecular brake pads.” HDACs are localized to promoters of active genes and act as a persistent clamp that requires strong activity-dependent signaling to temporarily release these complexes (or brake pads) to activate gene expression required for long-term memory formation. Thus, HDAC inhibition removes the “molecular brake pads” constraining the processes necessary for long-term memory and results in strong, persistent memory formation. PMID:21521655
The need for the vegetarian crew for long-term LSS
NASA Astrophysics Data System (ADS)
Gorgolewski, S.
The long-term space missions pose very stringent demands on the high degree of closure levels. One obvious requirements is to assure the human crew a steady state self-supporting and self-regenerating LSS environment. The strictly vegetarian crew is the primary requirement to minimize the cost and weight of the spacecraft. This ensures the minimal matter circulation problems, because we can also use for food as many as possible fuly edible plants with nex to none, non digestable plant tissues. One important task is to select a range of plants which should satisfy the nutritional needs of the crew for a long-term, in the range of several years. Preliminary fitotron experiments with lettuce, demonstrated that one can achieve this goal, with a plant which is wholy edible even with the roots. This has been achieved with the use of several teens times stronger electrical field, than the 130 V/m fair weather global atmospheric electrical field. More experiments are in progress for the extension of the list of such vegetarian food. The selection of suitable plants which meet these highly demanding selection criteria, has to be done and can be done in ground based experiments. Plants ensure one important requirements of a closed loop CO2 and O2 circulation with the vegetarian crew in the loop. Extensive research programs are needed for this purpose using large ground based instalations like the Biosphere 2. The success of the use of electrical fields as replacement of gravitational field in the fitotron which proved the dominating role over gravity, of several kV/m electical field intensities. It also proves the feasibility of improving the crop productivity in ground based greenhouses, provided that we do restore inside the missing in "normal" designs our global electrical field. The fair weather electrical field (not to mention the enhanced field) is the missing vital environmental factor which has been systematically "overlooked" in practically all greenhouses. It is the most likely factor whi ch was the main culprit of the failure of the manned long term Biosphere 2 experiment. Very strong evidence has been achieved in fitotron experiments, which have already been presented and published in the COSPAR2000 publication.
Liu, Fang; Huang, Changyong; He, Tengbin; Qian, Xiaogang; Liu, Yuansheng; Luo, Haibo
2003-02-01
Studies on the dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff showed that the contents of A1-P, Fe-P and Ca-P in soil cultivated layer increased greatly, and Olsen-P and algae-available P also accumulated obviously. The correlation coefficients of algae-available P content in the high-P soils (Olsen-P > 25 mg.kg-1) with the quantities of A1-P, Fe-P and Ca-P were 0.859**, 0.903** and 0.650*, respectively, of which, Fe-P was the most important. By a 30-min rainfall simulation experiment with a constant rainfall rate of 63.2 mm.h-1, the concentrations of dissolved reactive P and bio-available P in runoff from low-P upland fields (Olsen-P 4.62-15.9 mg.kg-1) were 2.81-4.17 micrograms.L-1 and 0.723-0.876 mg.L-1, respectively, whereas their concentrations in runoff from high-P upland fields (Olsen-P 29.4-59.2 mg.kg-1) were 0.026-0.714 mg.L-1 and 0.996-1.281 mg.L-1, respectively. Therefore, runoff from high-P upland fields could accelerate water eutrophication.
100,000 trees can't be wrong: permanent study plots and the value of time.
Sally Duncan
2004-01-01
In 1910, Thornton T. Munger, the first director of the PNW Research Station, established the first forested permanent study plot in the Pacific Northwest. He recognized that long-term field observation was the only approach that could provide real data on forest dynamics, which occur over time scales longer than human lifespans.For the next 80 years, Station...
Long-term variability of T Tauri stars using WASP
NASA Astrophysics Data System (ADS)
Rigon, Laura; Scholz, Alexander; Anderson, David; West, Richard
2017-03-01
We present a reference study of the long-term optical variability of young stars using data from the WASP project. Our primary sample is a group of well-studied classical T Tauri stars (CTTSs), mostly in Taurus-Auriga. WASP light curves cover time-scales of up to 7 yr and typically contain 10 000-30 000 data points. We quantify the variability as a function of time-scale using the time-dependent standard deviation 'pooled sigma'. We find that the overwhelming majority of CTTSs have a low-level variability with σ < 0.3 mag dominated by time-scales of a few weeks, consistent with rotational modulation. Thus, for most young stars, monitoring over a month is sufficient to constrain the total amount of variability over time-scales of up to a decade. The fraction of stars with a strong optical variability (σ > 0.3 mag) is 21 per cent in our sample and 21 per cent in an unbiased control sample. An even smaller fraction (13 per cent in our sample, 6 per cent in the control) show evidence for an increase in variability amplitude as a function of time-scale from weeks to months or years. The presence of long-term variability correlates with the spectral slope at 3-5 μm, which is an indicator of inner disc geometry, and with the U-B band slope, which is an accretion diagnostics. This shows that the long-term variations in CTTSs are predominantly driven by processes in the inner disc and in the accretion zone. Four of the stars with long-term variations show periods of 20-60 d, significantly longer than the rotation periods and stable over months to years. One possible explanation is cyclic changes in the interaction between the disc and the stellar magnetic field.
Holocene Paleosecular Variation From Dated Lava Flows on East Maui (Hawaii)
NASA Astrophysics Data System (ADS)
Herrero-Bervera, E.; Valet, J.
2006-12-01
A quasi-static inclination anomaly and low secular variation seem to dominate the historical and the long-term time averaged field in central Pacific. The period covering the past 10 kyr is crucial to study the field variability and to fill the gap between historical field measurements and long-term paleomagnetic records. We have conducted a paleomagnetic study of 13 sites of basaltic lava flows from the Maui island with 14C ages between 10.3 and 0.015 Ka. Two other sites dated at 45 Ka and 730 Ka were also sampled. Eight to ten samples from each site were demagnetized using thermal treatment and companion specimens from the same samples were demagnetized by alternating fields (af). Thermomagnetic and hysteresis measurements indicated that magnetite (575 degrees C) in fine grains was the dominant magnetic carrier, although in many cases we observed also a low-temperature phase which is likely carried by titanomagnetite with low titanium content. The existence of relatively high coercivities associated with these two mineralogical phases generated overlapping components which could not be properly isolated using af demagnetization. Successful results were obtained after thermal demagnetization for 13 sites with a mean inclination of 34.2 degrees +/-9 degrees. The mean inclination (Inc = 36.3 degrees) of the eleven sites younger than 10.5 Ka is very close to the value (37 degrees) of the geocentric axial dipole (GAD) at the site latitude, but the angular dispersion of 6.7 degrees for the VGPs about the spin axis is significantly lower than the predictions of the models of paleosecular variation at this latitude. The inclination variations for the past 10 Kyr are in excellent agreement with the very detailed dataset which has previously been obtained from the Big Island of Hawaii. The mean inclination is slightly lower than expected but this is likely caused by the lack of records between 5 and 7 ka B.P. Thus, there is no striking evidence for a magnetic anomaly under Hawaii during this period and the recently published records obtained for the past millions of years neither show any conclusive evidence in favor of a long-term persistent anomaly. However all studies report a very low dispersion of the VGPs which reflects low secular variation and likely low non-dipole field during the Holocene.
Exposure to electromagnetic fields aboard high-speed electric multiple unit trains.
Niu, D; Zhu, F; Qiu, R; Niu, Q
2016-01-01
High-speed electric multiple unit (EMU) trains generate high-frequency electric fields, low-frequency magnetic fields, and high-frequency wideband electromagnetic emissions when running. Potential human health concerns arise because the electromagnetic disturbances are transmitted mainly into the car body from windows, and from there to passengers and train staff. The transmission amount and amplitude distribution characteristics that dominate electromagnetic field emission need to be studied, and the exposure level of electromagnetic field emission to humans should be measured. We conducted a series of tests of the on board electromagnetic field distribution on several high-speed railway lines. While results showed that exposure was within permitted levels, the possibility of long-term health effects should be investigated.
NASA Astrophysics Data System (ADS)
Weisenburger, A.; Schroer, C.; Jianu, A.; Heinzel, A.; Konys, J.; Steiner, H.; Müller, G.; Fazio, C.; Gessi, A.; Babayan, S.; Kobzova, A.; Martinelli, L.; Ginestar, K.; Balbaud-Célerier, F.; Martín-Muñoz, F. J.; Soler Crespo, L.
2011-08-01
Considering the status of knowledge on corrosion and corrosion protection and especially the need for long term compatibility data of structural materials in HLM a set of experiments to generate reliable long term data was defined and performed. The long term corrosion behaviour of the two structural materials foreseen in ADS, 316L and T91, was investigated in the design relevant temperature field, i.e. from 300 to 550 °C. The operational window of the two steels in this temperature range was identified and all oxidation data were used to develop and validate the models of oxide scale growth in PbBi. A mechanistic model capable to predict the oxidation rate applying some experimentally fitted parameters has been developed. This model assumes parabolic oxidation and might be used for design and safety relevant investigations in future. Studies on corrosion barrier development allowed to define the required Al content for the formation of thin alumina scales in LBE. These results as well as future steps and required improvements are discussed. Variation of experimental conditions clearly showed that specific care has to be taken with respect to local flow conditions and oxygen concentrations.
NASA Astrophysics Data System (ADS)
Newberg, A. B.; Alavi, A.
The purpose of this paper is to review the potential functional and morphological effects of long duration space flight on the human central nervous system (CNS) and how current neuroimaging techniques may be utilized to study these effects. It must be determined if there will be any detrimental changes to the CNS from long term exposure to the space environment if human beings are to plan interplanetary missions or establish permanent space habitats. Research to date has focused primarily on the short term changes in the CNS as the result of space flight. The space environment has many factors such as weightlessness, electromagnetic fields, and radiation, that may impact upon the function and structure of the CNS. CNS changes known to occur during and after long term space flight include neurovestibular disturbances, cephalic fluid shifts, alterations in sensory perception, changes in proprioception, psychological disturbances, and cognitive changes. Animal studies have shown altered plasticity of the neural cytoarchitecture, decreased neuronal metabolism in the hypothalamus, and changes in neurotransmitter concentrations. Recent progress in the ability to study brain morphology, cerebral metabolism, and neurochemistry in vivo in the human brain would provide ample opportunity to investigate many of the changes that occur in the CNS as a result of space flight. These methods include positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetic resonance imaging (MRI).
Sasse, Stephanie; Bröckelmann, Paul J; Goergen, Helen; Plütschow, Annette; Müller, Horst; Kreissl, Stefanie; Buerkle, Carolin; Borchmann, Sven; Fuchs, Michael; Borchmann, Peter; Diehl, Volker; Engert, Andreas
2017-06-20
Purpose Combined-modality treatment is widely considered the standard of care in early-stage Hodgkin lymphoma (HL), and treatment intensity has been reduced over the last years. Long-term follow-up is important to judge both efficacy and safety of the different therapies used. Patients and Methods We analyzed updated follow-up data on 4,276 patients treated within the German Hodgkin Study Group trials HD7 and HD10 for early-stage favorable HL and HD8 and HD11 for early-stage unfavorable HL between 1993 and 2003. Results In HD7 (N = 627; median follow-up, 120 months), combined-modality treatment was superior to extended-field radiotherapy (RT), with 15-year progression-free survival (PFS) of 73% versus 52% (hazard ratio [HR], 0.5; 95% CI, 0.3 to 0.6; P < .001), without differences in overall survival (OS). In HD10 (N = 1,190; median follow-up, 98 months), noninferiority of two cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) plus 20 Gy involved-field (IF)-RT to more intensive four cycles of ABVD plus 30 Gy IF-RT was confirmed with 10-year PFS of 87% each (HR, 1.0; 95%, 0.6 to 1.5) and OS of 94% each (HR, 0.9; 95% CI, 0.5 to 1.6), respectively. In both trials, no differences in second neoplasias were observed. In HD8 (N = 1,064; median follow-up, 153 months), noninferiority of involved-field RT to extended-field RT regarding PFS was confirmed (HR, 1.0; 95% CI, 0.8 to 1.2). In HD11 (N = 1,395; median follow-up, 106 months), superiority of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone at baseline over ABVD was not observed. After BEACOPP baseline , 20 Gy IF-RT was noninferior to 30 Gy (10-year PFS, 84% v 84%; HR, 1.0; 95% CI, 0.7 to 1.5). In contrast, PFS was inferior in ABVD-treated patients receiving 20 Gy instead of 30 Gy IF-RT (10-year PFS, 76% v 84%; HR, 1.5; 95% CI, 1.0 to 2.1). No differences in OS or second neoplasias were observed in in both trials. Conclusion Long-term follow-up data of the four randomized trials largely support the current risk-adapted therapeutic strategies in early-stage HL. Nevertheless, continued follow-up is necessary to assess the long-term safety of currently applied therapeutic strategies.
Radiofrequency exposure in the Neonatal Medium Care Unit.
Calvente, I; Vázquez-Pérez, A; Fernández, M F; Núñez, M I; Múñoz-Hoyos, A
2017-01-01
The aims of this study were to characterize electromagnetic fields of radiofrequency (RF-EMF) levels generated in a Neonatal Medium Care Unit and to analyze RF-EMF levels inside unit's incubators. Spot and long-term measurements were made with a dosimeter. The spot measurement mean was 1.51±0.48V/m. Higher values were found in the proximity to the window and to the incubator evaluated. Mean field strength for the entire period of 17h was 0.81 (±0.07)V/m and the maximum value was 1.58V/m for long-term RF-EMF measurements in the incubator. Values found during the night period were higher than those found during the day period. It is important to consider RF-EMF exposure levels in neonatal care units, due to some evidence of adverse health effects found in children and adults. Characterization of RF-EMF exposure may be important to further investigate the mechanisms and underlying effects of electromagnetic fields (EMF) on infant health. A prudent avoidance strategy should be adopted because newborns are at a vulnerable stage of development and the actual impact of EMF on premature infants is unknown. Copyright © 2016 Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Nitrogen (N) loss from fertilization in agricultural fields has an unavoidable negative impact on the environment, and a better understanding of the major pathways can assist in developing best management practices. The aim of this study was to evaluate the fate of N fertilizers applied to acidic re...
ERIC Educational Resources Information Center
Kalimullin, Aydar M.; Yungblud, Valery T.; Khodyreva, Elena A.
2016-01-01
The relevance of the studied issue is based on the need to develop theoretical approaches to project management at a higher educational institution taking into consideration the specifics of the subject area of the projects that ensure finding the "growth points" and addressing the long-term objectives of a university in the field of…
ERIC Educational Resources Information Center
Liao, Hui; Chuang, Aichia
2007-01-01
This longitudinal field study integrates the theories of transformational leadership (TFL) and relationship marketing to examine how TFL influences employee service performance and customer relationship outcomes by transforming both (at the micro level) the service employees' attitudes and (at the macro level) the work unit's service climate.…
Field evaluations of a forestry version of DRAINMOD-NII model
S. Tian; M. A. Youssef; R.W. Skaggs; D.M. Amatya; G.M. Chescheir
2010-01-01
This study evaluated the performance of the newly developed forestry version of DRAINMOD-NII model using a long term (21-year) data set collected from an artificially drained loblolly pine (Pinus taeda L.) plantation in eastern North Carolina, U.S.A. The model simulates the main hydrological and biogeochemical processes in drained forested lands. The...
ERIC Educational Resources Information Center
Stolpe, Karin; Bjorklund, Lars
2013-01-01
This study aims to investigate the science content remembered by biology students 6 and 12 months after an ecology excursion. The students' memories were tested during a stimulated recall interview. The authors identified three different types of memories: "recall," "recognition" and "narratives." The "dual…
USDA-ARS?s Scientific Manuscript database
Models that estimate the effects of agricultural conservation practices on water quantity and quality have become increasingly important tools for short- and long-term assessments. In this study, we simulated the water quality and hydrology of a portion of the Jobos Bay watershed, Puerto Rico using...
U.S. Air Force Posture Statement 2007
2007-01-01
like the Raptor, the F–35a reaps the benefits of decades of advanced research, development and field experience . The F–35a will provide affordable...also increasing, and potential adversaries are already purchasing and fielding these complex and capable weapon systems. Many nations are...postured to meet our nation’s near -term requirements, our ability to meet steady state and surge requirements over the long term hinges on our ability to
Space transportation systems within ESA programmes: Current status and perspectives
NASA Astrophysics Data System (ADS)
Delahais, Maurice
1993-03-01
An overview of the space transportation aspects of the ESA (European Space Agency) programs as they result from history, present status, and decisions taken at the ministerial level conference in Granada, Spain is presented. The new factors taken into consideration for the long term plan proposed in Munich, Germany, the three strategic options for the reorientation of the ESA long term plan, and the essential elements of space transportation in the Granada long term plan in three areas of space activities, scientific, and commercial launches with expendable launch vehicles, manned flight and in-orbit infrastructure, and future transportation systems are outlined. The new ESA long term plan, in the field of space transportation systems, constitutes a reorientation of the initial program contemplated in previous councils at ministerial level. It aims at balancing the new economic situation with the new avenues of cooperation, and the outcome will be a new implementation of the space transportation systems policy.
Long time stability of lamps with nanostructural carbon field emission cathodes
NASA Astrophysics Data System (ADS)
Kalenik, J.; Firek, P.; Szmidt, J.; Czerwosz, E.; Kozłowski, M.; Stepińska, I.; Wódka, T.
2017-08-01
A luminescent lamp with field emission cathode was constructed and tested. Phosphor excited by electrons from field emission cathode is the source of light. The cathode is covered with nickel-carbon film containing multilayer carbon nanotubes that enhance electron emission from the cathode. Results of luminance stability measurements are presented. Luminance of elaborated luminance lamp is high enough for lighting application. Long term stability (1000 hours) is satisfactory for mass lamp application. Initial short time decrease of luminance is still too high and it needs reduction.
Pons, Elsa; Peris, Josep E; Peña, Leandro
2012-07-15
The future of genetic transformation as a tool for the improvement of fruit trees depends on the development of proper systems for the assessment of unintended effects in field-grown GM lines. In this study, we used eight transgenic lines of two different citrus types (sweet orange and citrange) transformed with the marker genes β-glucuronidase (uidA) and neomycin phosphotransferase II (nptII) as model systems to study for the first time in citrus the long-term stability of transgene expression and whether transgene-derived pleiotropic effects occur with regard to the morphology, development and fruit quality of orchard-grown GM citrus trees. The stability of the integration and expression of the transgenes was confirmed in 7-year-old, orchard-grown transgenic lines by Southern blot analysis and enzymatic assays (GUS and ELISA NPTII), respectively. Little seasonal variation was detected in the expression levels between plants of the same transgenic line in different organs and over the 3 years of analysis, confirming the absence of rearrangements and/or silencing of the transgenes after transferring the plants to field conditions. Comparisons between the GM citrus lines with their non-GM counterparts across the study years showed that the expression of these transgenes did not cause alterations of the main phenotypic and agronomic plant and fruit characteristics. However, when comparisons were performed between diploid and tetraploid transgenic citrange trees and/or between juvenile and mature transgenic sweet orange trees, significant and consistent differences were detected, indicating that factors other than their transgenic nature induced a much higher phenotypic variability. Our results indicate that transgene expression in GM citrus remains stable during long-term agricultural cultivation, without causing unexpected effects on crop characteristics. This study also shows that the transgenic citrus trees expressing the selectable marker genes that are most commonly used in citrus transformation were substantially equivalent to the non-transformed controls with regard to their overall agronomic performance, as based on the use of robust and powerful assessment techniques. Therefore, future studies of the possible pleiotropic effects induced by the integration and expression of transgenes in field-grown GM citrus may focus on the newly inserted trait(s) of biotechnological interest.
2012-01-01
Background The future of genetic transformation as a tool for the improvement of fruit trees depends on the development of proper systems for the assessment of unintended effects in field-grown GM lines. In this study, we used eight transgenic lines of two different citrus types (sweet orange and citrange) transformed with the marker genes β-glucuronidase (uidA) and neomycin phosphotransferase II (nptII) as model systems to study for the first time in citrus the long-term stability of transgene expression and whether transgene-derived pleiotropic effects occur with regard to the morphology, development and fruit quality of orchard-grown GM citrus trees. Results The stability of the integration and expression of the transgenes was confirmed in 7-year-old, orchard-grown transgenic lines by Southern blot analysis and enzymatic assays (GUS and ELISA NPTII), respectively. Little seasonal variation was detected in the expression levels between plants of the same transgenic line in different organs and over the 3 years of analysis, confirming the absence of rearrangements and/or silencing of the transgenes after transferring the plants to field conditions. Comparisons between the GM citrus lines with their non-GM counterparts across the study years showed that the expression of these transgenes did not cause alterations of the main phenotypic and agronomic plant and fruit characteristics. However, when comparisons were performed between diploid and tetraploid transgenic citrange trees and/or between juvenile and mature transgenic sweet orange trees, significant and consistent differences were detected, indicating that factors other than their transgenic nature induced a much higher phenotypic variability. Conclusions Our results indicate that transgene expression in GM citrus remains stable during long-term agricultural cultivation, without causing unexpected effects on crop characteristics. This study also shows that the transgenic citrus trees expressing the selectable marker genes that are most commonly used in citrus transformation were substantially equivalent to the non-transformed controls with regard to their overall agronomic performance, as based on the use of robust and powerful assessment techniques. Therefore, future studies of the possible pleiotropic effects induced by the integration and expression of transgenes in field-grown GM citrus may focus on the newly inserted trait(s) of biotechnological interest. PMID:22794278
NASA Astrophysics Data System (ADS)
Aron, F.; Estay, N.; Cembrano, J. M.; Yanez, G. A.
2016-12-01
We constructed a 3D Boundary Elements model simulating subduction of the Nazca plate underneath South America, from 29° to 38° S, to compute long-term surface deformation and slip rates on crustal faults imbedded in the upper-plate wedge of the Andean orogen. We tested our model on the San Ramón Fault (SRF), a major E-dipping, thrust structure limiting the western front of the Main Cordillera with surface expression along the entire, 40 km long, extension of the Santiago de Chile basin. Long-lived thrusting has produced more than 2 km of differential uplift of the mountains. Given its proximity to the country's largest city, this potentially seismogenic fault —dormant during historic times— has drawn increasing public attention. We used earthquake hypocenters captured over a one-year seismic deployment, 2D resistivity profiles, and published geologic cross-sections to determine the geometry of the SRF. The base of the lithosphere and plate interface surfaces were defined based on average Andean values and the Slab1.0 model. The simulation reproduces plate convergence and mechanic decoupling of the lithospheric plates across the subduction seismic cycle using mixed boundary conditions. Relative plate motion is achieved prescribing uniform, far-field horizontal displacement over the depth extension of both the oceanic and continental lithospheric plates. Long-term deformation is carried out in two steps. First, the modeled surfaces are allowed to slip freely emulating continuous slip on the subduction megathrust; subsequently, zero displacement is prescribed on the locking zone of the megathrust down to 40 km depth, while keeping the rest of the surfaces traction free, mimicking interseismic conditions. Long-term slip rate fields obtained for the SRF range between 0.1 and 1% the plate convergence rate, with maximum values near the surface. Interestingly, at an estimated 76-77 mm/yr relative plate motion velocity, those rates agree well with what has been reported on studies at one paleoseismic trench site across the fault. These results might contribute to determining possible seismic scenarios for Santiago but perhaps more importantly, our approach could be use in estimations of long-term slip rates and surface deformation due to other crustal structures with unknown displacement history.
HERBICIDE SENSITIVITY OF ECHINOCHLOA CRUS-GALLI POPULATIONS: A COMPARISON BETWEEN CROPPING SYSTEMS.
Claerhout, S; De Cauwer, B; Reheul, D
2014-01-01
Echinochloa crus-galli populations exhibit high morphological variability and their response to herbicides varies from field to field. Differential response to herbicides could reflect differences in selection pressure, caused by years of cropping system related herbicide usage. This study investigates the relation between herbicide sensitivity of Echinochloa crus-galli populations and the cropping system to which they were subjected. The herbicide sensitivity of Echinochloa crus-galli was evaluated for populations collected on 18 fields, representing three cropping systems, namely (1) a long-term organic cropping system, (2) a conventional cropping system with corn in crop rotation or (3) a conventional cropping system with long-term monoculture of corn. Each cropping system was represented by 6 E. crus-galli populations. All fields were located on sandy soils. Dose-response pot experiments were conducted in the greenhouse to assess the effectiveness of three foliar-applied corn herbicides: nicosulfuron (ALS-inhibitor), cycloxydim (ACCase-inhibitor) and topramezone (HPPD-inhibitor), and two soil-applied corn herbicides: S-metolachlor and dimethenamid-P (both VLCFA-inhibitors). Foliar-applied herbicides were tested at a quarter, half and full recommended doses. Soil-applied herbicides were tested within a dose range of 0-22.5 g a.i. ha(-1) for S-metolachlor and 0-45 g a.i. ha(-1) for dimethenamid-P. Foliar-applied herbicides were applied at the three true leaves stage. Soil-applied herbicides were treated immediately after sowing the radicle-emerged seeds. All experiments were performed twice. The foliage dry weight per pot was determined four weeks after treatment. Plant responses to herbicides were expressed as biomass reduction (%, relative to the untreated control). Sensitivity to foliar-applied herbicides varied among cropping systems. Compared to populations from monoculture corn fields, populations originating from organic fields were significantly more sensitive to cycloxydim, topramezone and nicosulfuron (resp. 5.3%, 5.9% and 12.3%). Populations from the conventional crop rotation system showed intermediate sensitivity levels. Contrary to foliar-applied herbicides, the effectiveness of soil-applied herbicides was not affected by cropping system. Integrated weed management may be necessary to preserve herbicide efficacy on the long term.
Detrital Controls on Dissolved Organic Matter in Soils: A Field Experiment
NASA Astrophysics Data System (ADS)
Lajtha, K.; Crow, S.; Yano, Y.; Kaushal, S.; Sulzman, E.; Sollins, P.
2004-12-01
We established a long-term field study in an old growth coniferous forest at the H.J. Andrews Experimental Forest, OR, to address how detrital quality and quantity control soil organic matter accumulation and stabilization. The Detritus Input and Removal Treatments (DIRT) plots consist of treatments that double leaf litter, double woody debris inputs, exclude litter inputs, or remove root inputs via trenching. We measured changes in soil solution chemistry with depth, and conducted long-term incubations of bulk soils and soil density fractions from different treatments in order to elucidate effects of detrital inputs on the relative amounts and lability of different soil C pools. In the field, the effect of adding woody debris was to increase dissolved organic carbon (DOC) concentrations in O-horizon leachate and at 30 cm, but not at 100 cm, compared to control plots, suggesting increased rates of DOC retention with added woody debris. DOC concentrations decreased through the soil profile in all plots to a greater degree than did dissolved organic nitrogen (DON), most likely due to preferential sorption of high C:N hydrophobic dissolved organic matter (DOM) in upper horizons; %hydrophobic DOM decreased significantly with depth, and hydrophilic DOM had a much lower and narrower C:N ratio. Although laboratory extracts of different litter types showed differences in DOM chemistry, percent hydrophobic DOM did not differ among detrital treatments in the field, suggesting microbial equalization of DOM leachate in the field. In long-term laboratory incubations, light fraction material did not have higher rates of respiration than heavy fraction or bulk soils, suggesting that physical protection or N availability controls different turnover times of heavy fraction material, rather than differences in chemical lability. Soils from plots that had both above- and below-ground litter inputs excluded had significantly lower DOC loss rates, and a non-significant trend for lower respiration rates . Soils from plots with added wood had similar respiration and DOC loss rates as control soils, suggesting that the additional DOC sorption observed in the field in these soils was stabilized in the soil and not readily lost upon incubation.
The discovery of long-term potentiation.
Lømo, Terje
2003-04-29
This paper describes circumstances around the discovery of long-term potentiation (LTP). In 1966, I had just begun independent work for the degree of Dr medicinae (PhD) in Per Andersen's laboratory in Oslo after an eighteen-month apprenticeship with him. Studying the effects of activating the perforant path to dentate granule cells in the hippocampus of anaesthetized rabbits, I observed that brief trains of stimuli resulted in increased efficiency of transmission at the perforant path-granule cell synapses that could last for hours. In 1968, Tim Bliss came to Per Andersen's laboratory to learn about the hippocampus and field potential recording for studies of possible memory mechanisms. The two of us then followed up my preliminary results from 1966 and did the experiments that resulted in a paper that is now properly considered to be the basic reference for the discovery of LTP.
[Social inequality in home care].
Möller, A; Osterfeld, A; Büscher, A
2013-06-01
Social inequality in Germany is discussed primarily with regard to educational or social welfare issues. There is a political consensus that more action should be taken to ensure equality of chances and fulfillment of basic needs for everyone. In long-term care these considerations have not yet taken place and there are hardly any research studies in this field. However, the startling rise of the need for long-term care will definitely require a discussion of social inequality in various care arrangements. To learn more about social inequality in home care, a qualitative approach was used and 16 home care nurses were interviewed. Our study shows that many care recipients face numerous problems they cannot handle on their own, which may even worsen their situation. In addition, the results reveal that facing social inequalities place a burden on nurses and influence their work performance.
NASA Astrophysics Data System (ADS)
Klein, E. C.; Holt, W. E.; Flesch, L. M.; Haines, A. J.
2006-12-01
The "jelly sandwich" and "crème brûlée" models divides continental lithosphere into distinct rheological layers. Dynamic models from thin sheet approximations provide estimates of the total strength of the lithosphere, but only to a thickness governed by the degree of mechanical coupling between rheological layers. If either the "jelly sandwich" or the "crème brûlée" model of the lithosphere is appropriate for the diffuse plate boundary zone setting of western North America, we expect a sharp contrast or decoupling between the strong upper crust ("bread") layer overlying the weak lower crustal ("jelly") layer. We examine the strength of the upper crust with and without strength contribution from the lower crust using thin sheet modeling methodologies. We use seismically defined densities to constrain vertical integrals of vertical stress (GPE) within the crust. Neglecting stresses due to flexure as well as shear stresses at the base of the crustal layer, lateral differences in GPE within the layer, are balanced solely by gradients in horizontal deviatoric stress [Flesch et al., 2001, 2006]. We solve the force-balance equations for the minimum deviatoric stress field associated with gradients of GPE. This deviatoric stress field calibrates the magnitude of deviatoric stresses within the seismogenic layer. We then solve for stress field boundary conditions associated with the stress field contributions from sources outside the modeled region that together with the minimum solution from GPE differences provide a best match with stress field indicators within western North America. In order to infer appropriate stress field indicators we develop a long-term kinematic strain rate and velocity field model. Where we use this strain rate field we assume that the relationship between deviatoric stress directions and kinematic strain rate directions is isotropic. In our calculations the seismogenic layer extends from the surface to either a uniform depth below sea level or to a variable depth below sea level constrained by heat flow. For the case of a long-term seismogenic layer with a uniform base 20 km below sea level, the long-term vertically integrated deviatoric stress magnitudes range between 0.05-0.75x10^{12} N/m, while the long-term vertically integrated strength magnitudes of the layer are of the order of 0.05-1.5x10^{12} N/m. These strength values constrain low long-term friction coefficients of 0.02-0.30 under hydrostatic to wet conditions in the Basin and Range region. We test the sensitivity of our solutions to different assumed brittle-ductile transition depths and find that coefficients of friction on faults, along with magnitudes of vertically integrated strength, are relatively insensitive to these assumed layer thicknesses. Moreover, through this sensitivity modeling we find evidence that our assumption of decoupling is valid for most of the Basin and Range region in that we find evidence for diminishing contributions to crustal strength with depth. We model the interface between the upper and lower crust by parameterization of a variable seismogenic thickness in the thin sheet equations. This allows us to estimate the strength of the top slice of "bread" without the incorporation of any "jelly". We find that most of the long-term strength of the crust within the diffuse plate boundary zone of western North America resides in the seismogenic layer of the upper crust.
Seasonal variability of atmospheric surface layer characteristics and weather pattern in Qatar
NASA Astrophysics Data System (ADS)
Samanta, Dhrubajyoti; Cheng, Way Lee; Sadr, Reza
2016-11-01
Qatar's economy is based on oil and gas industry, which are mostly located in coastal regions. Therefore, better understanding of coastal weather, characteristics of surface layer and turbulence exchange processes is much needed. However, the turbulent atmospheric layer study in this region is severely limited. To support the broader aim and study long term precise wind information, a micro-meteorological field campaign has been carried out in a coastal location of north Qatar. The site is based on a 9 m tower, installed at Al Ghariya in the northern coast of Qatar, equipped with three sonic anemometers, temperature-humidity sensor, radiometer and a weather station. This study shows results based on the period August 2015 to July 2016. Various surface layer characteristics and modellings coefficients based on Monin Obukhov similarity theory is studied for the year and seasonal change is noted. Along with the seasonal variabilities of different weather parameters also observed. We hope this long term field observational study will be very much helpful for research community especially for modelers. In addition, two beach and shoreline monitoring cameras installed at the site could give first time information on waves and shoreline changes, and wind-wave interaction in Qatar. An Preliminary Analysis of Wind-Wave Interaction in Qatar in the Context of Changing Climate.
[A Reflection on the Policy of Transcultural Long-Term Care for the Indigenous Peoples in Taiwan].
Subeq, Yi-Maun; Hsu, Mutsu
2016-06-01
Giving high-profile attention to socio-cultural and traditional beliefs in the promotion of long-term care policies enjoys strong, consensus support in the field of transcultural nursing. To protect the rights of indigenous people in Taiwan, the Ministry of Health and Welfare incorporated the concept of cultural care into the Long-term Care Services Act, which was approved by the Legislature in May 2014. However, the policies, resource strategies, manpower allocations, and staff educations and trainings related to this act are still await implementation in indigenous areas. Beyond the concept of professional healthcare, which considers cultural sensitivity, suitability, and ability, cultural care gives greater priority to crossing cultural barriers, integrating with the lifestyle of clients, and addressing their concerns in order to improve the well-being of target populations. The present article reviews current long-term care policy to highlight the importance of considering the cultural needs of the indigenous peoples of Taiwan in order to enhance the efficiency and impact of long-term care programs. Furthermore, the findings strongly recommend that additional resources be provided in order to meet the long-term care needs of indigenous communities. Finally, cultural-specific, long-term care service strategies should be promulgated in order to upgrade well-being in order to ease and comfort the feelings of indigenous people.
Utilizing Local Stream Ecology to Produce a Long Term Data Set as AN Authentic Research Tool
NASA Astrophysics Data System (ADS)
Gillies, S. L.; Janmaat, A.; Marsh, S. J.; Kanda, S.; Yakemchuk, A.; Peucker-Ehrenbrink, B.; Voss, B.
2017-12-01
Several streams in the Abbotsford region of the Fraser Valley, B.C., Canada, have been used as long term study sites for our ecology and geography courses. In collaboration with Woods Hole Oceanographic Institution we have been collecting water quality data from the Fraser River as part of the Global Rivers Observatory since 2009. The small stream sites are used for monitoring stream and river chemistry, physical characteristics, riparian influences, and using leaf litter bags to study decomposition rates and the macro-invertebrate community. In the introductory ecology course and the upper level independent freshwater ecology course, students conduct increasingly sophisticated experiments, such as: comparative stream chemistry and biological studies in one to several streams. These courses ladder into each other, students gain skills in the field and lab in their introductory course, such as preparing leaf litter bags, measuring dissolved phosphate and nitrate, and identifying invertebrates. In the introductory ecology course students begin applying statistics to their data and are encouraged to formulate their own hypothesis, and this is expanded upon in the upper level stream ecology course. In the upper level course, two to six students work as a team to conduct the field and laboratory studies, each student develops his/her own hypothesis and prepares a research report and poster. Students can analyze data collected for as long as 10 years from six different streams and the Fraser River. By investigating data from several years students are now able to observe trends.
Novel string field theory with also negative energy constituents/objects gives Veneziano amplitude
NASA Astrophysics Data System (ADS)
Nielsen, H. B.; Ninomiya, M.
2018-02-01
We have proposed a new type of string field theory. The main point of the present article is to cure some technical troubles: missing two out three terms in Veneziano amplitude. Our novel string field theory, describes a theory with many strings in terms of "objects", which are not exactly, but close to Charles Thorn's string bits. The new point is that the objects in terms of which the universe states are constructed, and which have an essentially 26-momentum variable called J μ , can have the energy J 0 be also negative as well as positive. We get a long way in deriving in this model the Veneziano model and obtain all the three terms needed for a four point amplitude. This result strongly indicates that our novel string field theory is indeed string theory.
NASA Astrophysics Data System (ADS)
Poltavtsev, S. V.; Langer, L.; Yugova, I. A.; Salewski, M.; Kapitonov, Y. V.; Yakovlev, D. R.; Karczewski, G.; Wojtowicz, T.; Akimov, I. A.; Bayer, M.
2016-10-01
We use spontaneous (two-pulse) and stimulated (three-pulse) photon echoes for studying the coherent evolution of optically excited ensemble of trions which are localized in semiconductor CdTe/CdMgTe quantum well. Application of transverse magnetic field leads to the Larmor precession of the resident electron spins, which shuffles optically induced polarization between optically accessible and inaccessible states. This results in several spectacular phenomena. First, magnetic field induces oscillations of spontaneous photon echo amplitude. Second, in three-pulse excitation scheme, the photon echo decay is extended by several orders of magnitude. In this study, short-lived optical excitation which is created by the first pulse is coherently transferred into a long-lived electron spin state using the second optical pulse. This coherent spin state of electron ensemble persists much longer than any optical excitation in the system, preserving information on initial optical field, which can be retrieved as a photon echo by means of third optical pulse.
Long-time asymptotics of the Navier-Stokes and vorticity equations on R(3).
Gallay, Thierry; Wayne, C Eugene
2002-10-15
We use the vorticity formulation to study the long-time behaviour of solutions to the Navier-Stokes equation on R(3). We assume that the initial vorticity is small and decays algebraically at infinity. After introducing self-similar variables, we compute the long-time asymptotics of the rescaled vorticity equation up to second order. Each term in the asymptotics is a self-similar divergence-free vector field with Gaussian decay at infinity, and the coefficients in the expansion can be determined by solving a finite system of ordinary differential equations. As a consequence of our results, we are able to characterize the set of solutions for which the velocity field satisfies ||u(.,t)||(L(2)) = o(t(-5/4)) as t-->+ infinity. In particular, we show that these solutions lie on a smooth invariant submanifold of codimension 11 in our function space.
Stein, Karen
2016-01-01
This commentary discusses the need to evaluate the impact of World Elder Abuse Awareness Day activities, the elder abuse field's most sustained public awareness initiative. A logic model is proposed with measures for short-term, medium-term, and long-term outcomes for community-based programs.
Near-field effects of asteroid impacts in deep water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gisler, Galen R; Weaver, Robert P; Gittings, Michael L
2009-06-11
Our previous work has shown that ocean impacts of asteroids below 500 m in diameter do not produce devastating long-distance tsunamis. Nevertheless, a significant portion of the ocean lies close enough to land that near-field effects may prove to be the greatest danger from asteroid impacts in the ocean. Crown splashes and central jets that rise up many kilometres into the atmosphere can produce, upon their collapse, highly non-linear breaking waves that could devastate shorelines within a hundred kilometres of the impact site. We present illustrative calculations, in two and three dimensions, of such impacts for a range of asteroidmore » sizes and impact angles. We find that, as for land impacts, the greatest dangers from oceanic impacts are the short-term near-field, and long-term atmospheric effects.« less
ERIC Educational Resources Information Center
Papatheodoropoulos, Costas; Kouvaros, Stylianos
2016-01-01
The ability of the ventral hippocampus (VH) for long-lasting long-term potentiation (LTP) and the mechanisms underlying its lower ability for shortlasting LTP compared with the dorsal hippocampus (DH) are unknown. Using recordings of field excitatory postsynaptic potentials (EPSPs) from the CA1 field of adult rat hippocampal slices, we found that…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jingu, Keiichi, E-mail: kjingu-jr@rad.med.tohoku.ac.jp; Ariga, Hisanori; Nemoto, Kenji
2012-05-01
Purpose: To evaluate the long-term efficacy and toxicity of definitive radiochemotherapy for solitary lymph node metastasis after curative surgery of esophageal cancer. Methods and Materials: We performed a retrospective review of 35 patients who underwent definitive radiochemotherapy at Tohoku University Hospital between 2000 and 2009 for solitary lymph node metastasis after curative esophagectomy with lymph node dissection for esophageal cancer. Radiotherapy doses ranged from 60 to 66 Gy (median, 60 Gy). Concurrent chemotherapy was platinum based in all patients. The endpoints of the present study were overall survival, cause-specific survival, progression-free survival, irradiated-field control, overall tumor response, and prognostic factors.more » Results: The median observation period for survivors was 70.0 months. The 5-year overall survival was 39.2% (median survival, 39.0 months). The 5-year cause-specific survival, progression-free survival, and irradiated-field control were 43.3%, 31.0% and 59.9%, respectively. Metastatic lesion, size of the metastatic lymph node, and performance status before radiochemotherapy were significantly correlated with prognosis. Complete response and partial response were observed in 22.9% and 57.1% of the patients, respectively. There was no Grade 3 or higher adverse effect based on theCommon Terminology Criteria for Adverse Events (CTCAE v3.0) in the late phase. Conclusions: Based on our study findings, approximately 40% of patients with solitary lymph node metastasis after curative resection for esophageal cancer have a chance of long-term survival with definitive radiochemotherapy.« less
The potential to characterize ecological data with terrestrial laser scanning in Harvard Forest, MA.
Orwig, D A; Boucher, P; Paynter, I; Saenz, E; Li, Z; Schaaf, C
2018-04-06
Contemporary terrestrial laser scanning (TLS) is being used widely in forest ecology applications to examine ecosystem properties at increasing spatial and temporal scales. Harvard Forest (HF) in Petersham, MA, USA, is a long-term ecological research (LTER) site, a National Ecological Observatory Network (NEON) location and contains a 35 ha plot which is part of Smithsonian Institution's Forest Global Earth Observatory (ForestGEO). The combination of long-term field plots, eddy flux towers and the detailed past historical records has made HF very appealing for a variety of remote sensing studies. Terrestrial laser scanners, including three pioneering research instruments: the Echidna Validation Instrument, the Dual-Wavelength Echidna Lidar and the Compact Biomass Lidar, have already been used both independently and in conjunction with airborne laser scanning data and forest census data to characterize forest dynamics. TLS approaches include three-dimensional reconstructions of a plot over time, establishing the impact of ice storm damage on forest canopy structure, and characterizing eastern hemlock ( Tsuga canadensis ) canopy health affected by an invasive insect, the hemlock woolly adelgid ( Adelges tsugae ). Efforts such as those deployed at HF are demonstrating the power of TLS as a tool for monitoring ecological dynamics, identifying emerging forest health issues, measuring forest biomass and capturing ecological data relevant to other disciplines. This paper highlights various aspects of the ForestGEO plot that are important to current TLS work, the potential for exchange between forest ecology and TLS, and emphasizes the strength of combining TLS data with long-term ecological field data to create emerging opportunities for scientific study.
The potential to characterize ecological data with terrestrial laser scanning in Harvard Forest, MA
Boucher, P.; Saenz, E.; Li, Z.
2018-01-01
Contemporary terrestrial laser scanning (TLS) is being used widely in forest ecology applications to examine ecosystem properties at increasing spatial and temporal scales. Harvard Forest (HF) in Petersham, MA, USA, is a long-term ecological research (LTER) site, a National Ecological Observatory Network (NEON) location and contains a 35 ha plot which is part of Smithsonian Institution's Forest Global Earth Observatory (ForestGEO). The combination of long-term field plots, eddy flux towers and the detailed past historical records has made HF very appealing for a variety of remote sensing studies. Terrestrial laser scanners, including three pioneering research instruments: the Echidna Validation Instrument, the Dual-Wavelength Echidna Lidar and the Compact Biomass Lidar, have already been used both independently and in conjunction with airborne laser scanning data and forest census data to characterize forest dynamics. TLS approaches include three-dimensional reconstructions of a plot over time, establishing the impact of ice storm damage on forest canopy structure, and characterizing eastern hemlock (Tsuga canadensis) canopy health affected by an invasive insect, the hemlock woolly adelgid (Adelges tsugae). Efforts such as those deployed at HF are demonstrating the power of TLS as a tool for monitoring ecological dynamics, identifying emerging forest health issues, measuring forest biomass and capturing ecological data relevant to other disciplines. This paper highlights various aspects of the ForestGEO plot that are important to current TLS work, the potential for exchange between forest ecology and TLS, and emphasizes the strength of combining TLS data with long-term ecological field data to create emerging opportunities for scientific study. PMID:29503723
Crone, A.J.; De Martini, P. M.; Machette, M.M.; Okumura, K.; Prescott, J.R.
2003-01-01
Paleoseismic studies of two historically aseismic Quaternary faults in Australia confirm that cratonic faults in stable continental regions (SCR) typically have a long-term behavior characterized by episodes of activity separated by quiescent intervals of at least 10,000 and commonly 100,000 years or more. Studies of the approximately 30-km-long Roopena fault in South Australia and the approximately 30-km-long Hyden fault in Western Australia document multiple Quaternary surface-faulting events that are unevenly spaced in time. The episodic clustering of events on cratonic SCR faults may be related to temporal fluctuations of fault-zone fluid pore pressures in a volume of strained crust. The long-term slip rate on cratonic SCR faults is extremely low, so the geomorphic expression of many cratonic SCR faults is subtle, and scarps may be difficult to detect because they are poorly preserved. Both the Roopena and Hyden faults are in areas of limited or no significant seismicity; these and other faults that we have studied indicate that many potentially hazardous SCR faults cannot be recognized solely on the basis of instrumental data or historical earthquakes. Although cratonic SCR faults may appear to be nonhazardous because they have been historically aseismic, those that are favorably oriented for movement in the current stress field can and have produced unexpected damaging earthquakes. Paleoseismic studies of modern and prehistoric SCR faulting events provide the basis for understanding of the long-term behavior of these faults and ultimately contribute to better seismic-hazard assessments.
NASA Astrophysics Data System (ADS)
Vache, K. B.
2015-12-01
This study outlines the development and use of an integrated catchment model that has been developed as part of a long-term project focused on impacts of short-rotation loblolly pine production as a biofuel feedstock. The field-related aspects of the project were initiated in 2009 and focused on the development of a baseline dataset developed from hydrometric, isotopic, and water quality monitoring of a set of small paired catchments. In the winter of 2013 a series of treatments, representing typical forest management strategies in the southeastern US were implemented, and monitoring will continue through 2018. We have used the available long-term measurements to outline a conceptual model of catchment hydrology in this region which is characterized by low gradient slopes and deep sandy soils. The conceptual model has been translated into an object-oriented landscape modeling framework, allowing for the development of a set of long term landuse scenarios which serve as temporally-varying boundaries conditions for the catchment model. The presentation focuses primarily on these modeling results, with particular emphasis on the influence of short rotation harvest on groundwater recharge and stream water quantity over decadal scales.
Chuah, Yon Jin; Koh, Yi Ting; Lim, Kaiyang; Menon, Nishanth V.; Wu, Yingnan; Kang, Yuejun
2015-01-01
Polydimethylsiloxane (PDMS) has been extensively exploited to study stem cell physiology in the field of mechanobiology and microfluidic chips due to their transparency, low cost and ease of fabrication. However, its intrinsic high hydrophobicity renders a surface incompatible for prolonged cell adhesion and proliferation. Plasma-treated or protein-coated PDMS shows some improvement but these strategies are often short-lived with either cell aggregates formation or cell sheet dissociation. Recently, chemical functionalization of PDMS surfaces has proved to be able to stabilize long-term culture but the chemicals and procedures involved are not user- and eco-friendly. Herein, we aim to tailor greener and biocompatible PDMS surfaces by developing a one-step bio-inspired polydopamine coating strategy to stabilize long-term bone marrow stromal cell culture on PDMS substrates. Characterization of the polydopamine-coated PDMS surfaces has revealed changes in surface wettability and presence of hydroxyl and secondary amines as compared to uncoated surfaces. These changes in PDMS surface profile contribute to the stability in BMSCs adhesion, proliferation and multipotency. This simple methodology can significantly enhance the biocompatibility of PDMS-based microfluidic devices for long-term cell analysis or mechanobiological studies. PMID:26647719
A long-term evaluation of biopsy darts and DNA to estimate cougar density
Beausoleil, Richard A.; Clark, Joseph D.; Maletzke, Benjamin T.
2016-01-01
Accurately estimating cougar (Puma concolor) density is usually based on long-term research consisting of intensive capture and Global Positioning System collaring efforts and may cost hundreds of thousands of dollars annually. Because wildlife agency budgets rarely accommodate this approach, most infer cougar density from published literature, rely on short-term studies, or use hunter harvest data as a surrogate in their jurisdictions; all of which may limit accuracy and increase risk of management actions. In an effort to develop a more cost-effective long-term strategy, we evaluated a research approach using citizen scientists with trained hounds to tree cougars and collect tissue samples with biopsy darts. We then used the DNA to individually identify cougars and employed spatially explicit capture–recapture models to estimate cougar densities. Overall, 240 tissue samples were collected in northeastern Washington, USA, producing 166 genotypes (including recaptures and excluding dependent kittens) of 133 different cougars (8-25/yr) from 2003 to 2011. Mark–recapture analyses revealed a mean density of 2.2 cougars/100 km2 (95% CI=1.1-4.3) and stable to decreasing population trends (β=-0.048, 95% CI=-0.106–0.011) over the 9 years of study, with an average annual harvest rate of 14% (range=7-21%). The average annual cost per year for field sampling and genotyping was US$11,265 ($422.24/sample or $610.73/successfully genotyped sample). Our results demonstrated that long-term biopsy sampling using citizen scientists can increase capture success and provide reliable cougar-density information at a reasonable cost.
A novel methodology for interpreting air quality measurements from urban streets using CFD modelling
NASA Astrophysics Data System (ADS)
Solazzo, Efisio; Vardoulakis, Sotiris; Cai, Xiaoming
2011-09-01
In this study, a novel computational fluid dynamics (CFD) based methodology has been developed to interpret long-term averaged measurements of pollutant concentrations collected at roadside locations. The methodology is applied to the analysis of pollutant dispersion in Stratford Road (SR), a busy street canyon in Birmingham (UK), where a one-year sampling campaign was carried out between August 2005 and July 2006. Firstly, a number of dispersion scenarios are defined by combining sets of synoptic wind velocity and direction. Assuming neutral atmospheric stability, CFD simulations are conducted for all the scenarios, by applying the standard k-ɛ turbulence model, with the aim of creating a database of normalised pollutant concentrations at specific locations within the street. Modelled concentration for all wind scenarios were compared with hourly observed NO x data. In order to compare with long-term averaged measurements, a weighted average of the CFD-calculated concentration fields was derived, with the weighting coefficients being proportional to the frequency of each scenario observed during the examined period (either monthly or annually). In summary the methodology consists of (i) identifying the main dispersion scenarios for the street based on wind speed and directions data, (ii) creating a database of CFD-calculated concentration fields for the identified dispersion scenarios, and (iii) combining the CFD results based on the frequency of occurrence of each dispersion scenario during the examined period. The methodology has been applied to calculate monthly and annually averaged benzene concentration at several locations within the street canyon so that a direct comparison with observations could be made. The results of this study indicate that, within the simplifying assumption of non-buoyant flow, CFD modelling can aid understanding of long-term air quality measurements, and help assessing the representativeness of monitoring locations for population exposure studies.
The management of patients with limited-stage classical Hodgkin lymphoma.
Gospodarowicz, Mary K; Meyer, Ralph M
2006-01-01
The term limited-stage Hodgkin lymphoma refers to those patients with stage I-II disease and an absence of bulky disease. Among those patients with classical Hodgkin lymphoma, approximately one-third of patients will fall into this category. As long-term disease control can now be anticipated in more than 90% of these patients, management strategies must increasingly address the need to reduce the long-term treatment-related risks. Current treatment options include use of combined modality therapy that includes an abbreviated course of chemotherapy and involved-field radiation or treatment with chemotherapy, currently consisting of ABVD, as a single modality. The choice of treatment between these two options involves specific trade-offs that must balance issues of disease control against long-term risk of late effects.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Russell, R.S.; Shone, M.G.T.
ABS>Experimental results are given of a long term study on the migration and fixation of strontium and cesium in several types of soil The investigations were designed to approximate to field conditions in which the soil remained undisturbed by cultivation. The effects of the addition of nutrients and of a permanent crop of ryegrass grown on the artificially contaminated soils were also examined. The relevance of processes of migration and fixation to assessments of the uptake of strontium and cesium by crop plants is considered in the light of field experiments. (auth)
THE EVOLUTION OF THE ELECTRIC CURRENT DURING THE FORMATION AND ERUPTION OF ACTIVE-REGION FILAMENTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Jincheng; Yan, Xiaoli; Qu, Zhongquan
We present a comprehensive study of the electric current related to the formation and eruption of active region filaments in NOAA AR 11884. The vertical current on the solar surface was investigated by using vector magnetograms (VMs) observed by HMI on board the Solar Dynamics Observatory. To obtain the electric current along the filament's axis, we reconstructed the magnetic fields above the photosphere by using nonlinear force-free field extrapolation based on photospheric VMs. Spatio-temporal evolutions of the vertical current on the photospheric surface and the horizontal current along the filament's axis were studied during the long-term evolution and eruption-related period,more » respectively. The results show that the vertical currents of the entire active region behaved with a decreasing trend and the magnetic fields also kept decreasing during the long-term evolution. For the eruption-related evolution, the mean transverse field strengths decreased before two eruptions and increased sharply after two eruptions in the vicinity of the polarity inversion lines underneath the filament. The related vertical current showed different behaviors in two of the eruptions. On the other hand, a very interesting feature was found: opposite horizontal currents with respect to the current of the filament's axis appeared and increased under the filament before the eruptions and disappeared after the eruptions. We suggest that these opposite currents were carried by the new flux emerging from the photosphere bottom and might be the trigger mechanism for these filament eruptions.« less
NASA Astrophysics Data System (ADS)
Kiss, T. S.; Erdélyi, R.
2018-04-01
This study aims to provide further evidence for the potential influence of the global solar magnetic field on localized chromospheric jets, the macrospicules (MS). To find a connection between the long-term variation of properties of MS and other solar activity proxies, including, e.g., the temporal variation of the frequency shift of solar global oscillations, sunspot area, etc., a database overarching seven years of observations was compiled. This database contains 362 MS, based on observations at the 30.4 nm of the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. Three of the five investigated physical properties of MS show a clear long-term temporal variation after smoothing the raw data. Wavelet analysis of the temporal variation of maximum length, maximum area, and average velocity is carried out. The results reveal a strong pattern of periodicities at around 2 years (also referred to as quasi-biennial oscillations—QBOs). A comparison with solar activity proxies that also possess the properties of QBOs provides some interesting features: the minima and maxima of QBOs of MS properties occur at around the same epoch as the minima and maxima of these activity proxies. For most of the time span investigated, the oscillations are out of phase. This out-of-phase behavior was also corroborated by a cross-correlation analysis. These results suggest that the physical processes that generate and drive the long-term evolution of the global solar activity proxies may be coupled to the short-term local physical processes driving the macrospicules, and, therefore modulate the properties of local dynamics.
Long-term evolution of the force-free twisted magnetosphere of a magnetar
NASA Astrophysics Data System (ADS)
Akgün, T.; Cerdá-Durán, P.; Miralles, J. A.; Pons, J. A.
2017-12-01
We study the long-term quasi-steady evolution of the force-free magnetosphere of a magnetar coupled to its internal magnetic field. We find that magnetospheric currents can be maintained on long time-scales of the order of thousands of years. Meanwhile, the energy, helicity and twist stored in the magnetosphere all gradually increase over the course of this evolution, until a critical point is reached, beyond which a force-free magnetosphere cannot be constructed. At this point, some large-scale magnetospheric rearrangement, possibly resulting in an outburst or a flare, must occur, releasing a large fraction of the stored energy, helicity and twist. After that, the quasi-steady evolution should continue in a similar manner from the new initial conditions. The time-scale for reaching this critical point depends on the overall magnetic field strength and on the relative fraction of the toroidal field. The energy stored in the force-free magnetosphere is found to be up to ∼30 per cent larger than the corresponding vacuum energy. This implies that for a 1014 G field at the pole, the energy budget available for fast magnetospheric events is of the order of a few 1044 erg. The spin-down rate is estimated to increase by up to ∼60 per cent, since the dipole content in the magnetosphere is enhanced by the currents present there. A rough estimate of the braking index n reveals that it is systematically n < 3 for the most part of the evolution, consistent with actual measurements for pulsars and early estimates for several magnetars.
Nitrogen dynamics in organic and conventional cotton production systems in India
NASA Astrophysics Data System (ADS)
Duboc, O.; Adamtey, N.; Forster, D.; Cadisch, G.
2012-04-01
Ongoing population growth still represents a challenge to agricultural production (food, fiber and fuel material supply). In spite of the undeniable achievements reached with the "green revolution" technologies, there is a growing awareness among scientists and policy makers that diverse and integrated approaches which are both productive and sustainable are now necessary to meet the agricultural challenges. Integrated and organic agriculture are such alternatives which need to be better investigated and implemented. While long-term experiments in temperate regions have assessed the effect of organic agriculture on different crops and soil quality, there is currently a lack of reliable data from tropical regions, such as findings arising from long-term systems comparison trials. This has necessitated a long-term system comparison trials in Kenya, Bolivia and India by the Research Institute of Organic Agriculture (FiBL) and its partners (icipe, BioRe, Ecotop and Institute of Ecology) (www.systems-comparison.fibl.org). In India the project is based in Madhya Pradesh, in which organic and conventional production systems are being compared in a 2-yr crop rotation - cotton (yr 1) and soybean-wheat (yr 2). The field trial is planned for a time span of 10-20 years, in order to investigate long-term effects of those production systems on yields, soil characteristics, or economic return. A PhD study is incorporated into this project to investigate the effect of the production systems on soil characteristics. The main focus will be on nitrogen cycling under the different production systems. Particular attention will be given to nitrogen use efficiencies and the synchrony of nitrogen availability (e.g. nitrogen mineralization with the polyethylene bag technique, monitoring of soil mineral N) with plant nitrogen uptake, for which allometric equations will be calibrated in order to circumvent destructive sampling on the plots of the long-term experiment. Nitrogen losses - leaching and gaseous emissions - will also be investigated with methods such as buried ion exchange resin cores and gas sampling in the field. Furthermore, the project will test management solutions to improve nitrogen use efficiencies in both, organic and conventional systems, such as the introduction of leguminous intercrops in cotton, which is the main cash crop in the system and which also has the highest requirements for fertilization. This poster thus mainly discusses methodic issues relating to the planned study.
Rodríguez-González, Patricia María; Albuquerque, António; Martínez-Almarza, Miguel; Díaz-Delgado, Ricardo
2017-11-01
Implementing long-term monitoring programs that effectively inform conservation plans is a top priority in environmental management. In floodplain forests, historical pressures interplay with the complex multiscale dynamics of fluvial systems and require integrative approaches to pinpoint drivers for their deterioration and ecosystem services loss. Combining a conceptual framework such as the Driver-Pressure-State-Impact-Response (DPSIR) with the development of valid biological indicators can contribute to the analysis of the driving forces and their effects on the ecosystem in order to formulate coordinated conservation measures. In the present study, we evaluate the initial results of a decade (2004-2014) of floodplain forest monitoring. We adopted the DPSIR framework to summarize the main drivers in land use and environmental change, analyzed the effects on biological indicators of foundation trees and compared the consistency of the main drivers and their effects at two spatial scales. The monitoring program was conducted in one of the largest and best preserved floodplain forests in SW Europe located within Doñana National Park (Spain) which is dominated by Salix atrocinerea and Fraxinus angustifolia. The program combined field (in situ) surveys on a network of permanent plots with several remote sensing sources. The accuracy obtained in spectral classifications allowed shifts in species cover across the whole forest to be detected and assessed. However, remote sensing did not reflect the ecological status of forest populations. The field survey revealed a general decline in Salix populations, especially in the first five years of sampling -a factor probably associated with a lag effect from past human impact on the hydrology of the catchment and recent extreme climatic episodes (drought). In spite of much reduced seed regeneration, a resprouting strategy allows long-lived Salix individuals to persist in complex spatial dynamics. This suggests the beginning of a recovery resulting from recent coordinated societal responses to control excessive water extraction in the catchment, highlighting the need for continuing long-term monitoring. The DPSIR framework proved useful as a conceptual tool in analyzing the entire environmental system, while both field and remote sensing approaches complemented each other in quantifying indicator trends, improving the monitoring design and informing conservation plans. Copyright © 2017 Elsevier Ltd. All rights reserved.
Long term stability of nanowire nanoelectronics in physiological environments.
Zhou, Wei; Dai, Xiaochuan; Fu, Tian-Ming; Xie, Chong; Liu, Jia; Lieber, Charles M
2014-03-12
Nanowire nanoelectronic devices have been exploited as highly sensitive subcellular resolution detectors for recording extracellular and intracellular signals from cells, as well as from natural and engineered/cyborg tissues, and in this capacity open many opportunities for fundamental biological research and biomedical applications. Here we demonstrate the capability to take full advantage of the attractive capabilities of nanowire nanoelectronic devices for long term physiological studies by passivating the nanowire elements with ultrathin metal oxide shells. Studies of Si and Si/aluminum oxide (Al2O3) core/shell nanowires in physiological solutions at 37 °C demonstrate long-term stability extending for at least 100 days in samples coated with 10 nm thick Al2O3 shells. In addition, investigations of nanowires configured as field-effect transistors (FETs) demonstrate that the Si/Al2O3 core/shell nanowire FETs exhibit good device performance for at least 4 months in physiological model solutions at 37 °C. The generality of this approach was also tested with in studies of Ge/Si and InAs nanowires, where Ge/Si/Al2O3 and InAs/Al2O3 core/shell materials exhibited stability for at least 100 days in physiological model solutions at 37 °C. In addition, investigations of hafnium oxide-Al2O3 nanolaminated shells indicate the potential to extend nanowire stability well beyond 1 year time scale in vivo. These studies demonstrate that straightforward core/shell nanowire nanoelectronic devices can exhibit the long term stability needed for a range of chronic in vivo studies in animals as well as powerful biomedical implants that could improve monitoring and treatment of disease.
Long Term Stability of Nanowire Nanoelectronics in Physiological Environments
2015-01-01
Nanowire nanoelectronic devices have been exploited as highly sensitive subcellular resolution detectors for recording extracellular and intracellular signals from cells, as well as from natural and engineered/cyborg tissues, and in this capacity open many opportunities for fundamental biological research and biomedical applications. Here we demonstrate the capability to take full advantage of the attractive capabilities of nanowire nanoelectronic devices for long term physiological studies by passivating the nanowire elements with ultrathin metal oxide shells. Studies of Si and Si/aluminum oxide (Al2O3) core/shell nanowires in physiological solutions at 37 °C demonstrate long-term stability extending for at least 100 days in samples coated with 10 nm thick Al2O3 shells. In addition, investigations of nanowires configured as field-effect transistors (FETs) demonstrate that the Si/Al2O3 core/shell nanowire FETs exhibit good device performance for at least 4 months in physiological model solutions at 37 °C. The generality of this approach was also tested with in studies of Ge/Si and InAs nanowires, where Ge/Si/Al2O3 and InAs/Al2O3 core/shell materials exhibited stability for at least 100 days in physiological model solutions at 37 °C. In addition, investigations of hafnium oxide-Al2O3 nanolaminated shells indicate the potential to extend nanowire stability well beyond 1 year time scale in vivo. These studies demonstrate that straightforward core/shell nanowire nanoelectronic devices can exhibit the long term stability needed for a range of chronic in vivo studies in animals as well as powerful biomedical implants that could improve monitoring and treatment of disease. PMID:24479700
Residents' reactions to long-term sonic boom exposure: Preliminary results
NASA Technical Reports Server (NTRS)
Fields, James M.; Moulton, Carey; Baumgartner, Robert M.; Thomas, Jeff
1994-01-01
This presentation is about residents' reactions to sonic booms in a long-term sonic boom exposure environment. Although two phases of the data collection have been completed, the analysis of the data has only begun. The results are thus preliminary. The list of four authors reflects the complex multi-disciplinary character of any field study such as this one. Carey Moulton is responsible for Wyle Laboratories' acoustical data collection effort. Robert Baumgartner and Jeff Thomas of HBRS, a social science research firm, are responsible for social survey field work and data processing. The study is supported by the NASA Langley Research Center. The study has several objectives. The preliminary data addresses two of the primary objectives. The first objective is to describe the reactions to sonic booms of people who are living where sonic booms are a routine, recurring feature of the acoustical environment. The second objective is to compare these residents' reactions to the reactions of residents who hear conventional aircraft noise around airports. Here is an overview of the presentation. This study will first be placed in the context of previous community survey research on sonic booms. Next the noise measurement program will be briefly described and part of a social survey interview will be presented. Finally data will be presented on the residents' reactions and these reactions will be compared with reactions to conventional aircraft. Twelve community studies of residents' reactions to sonic booms were conducted in the United States and Europe in the 1960's and early 1970's. None of the 12 studies combined three essential ingredients that are found in the present study. Residents' long-term responses are related to a measured noise environment. Sonic booms are a permanent feature of the residential environment. The respondents' do not live on a military base. The present study is important because it provides the first dose/response relationship for sonic booms that could be expected to apply to residents in civilian residential areas.
Infrequent composted biosolids applications affect semi-arid grassland soils and vegetation.
Ippolito, J A; Barbarick, K A; Paschke, M W; Brobst, R B
2010-05-01
Monitoring of repeated composted biosolids applications is necessary for improving beneficial reuse program management strategies, because materials will likely be reapplied to the same site at a future point in time. A field trial evaluated a single and a repeated composted biosolids application in terms of long-term (13-14 years) and short-term (2-3 years) effects, respectively, on soil chemistry and plant community in a Colorado semi-arid grassland. Six composted biosolids rates (0, 2.5, 5, 10, 21, 30 Mg ha(-1)) were surface applied in a split-plot design study with treatment (increasing compost rates) as the main factor and co-application time (1991, or 1991 and 2002) as the split factor applications. Short- and long-term treatment effects were evident in 2004 and 2005 for soil 0-8 cm depth pH, EC, NO(3)-N, NH(4)-N, total N, and AB-DTPA soil Cd, Cu, Mo, Zn, P, and Ba. Soil organic matter increases were still evident 13 and 14 years following composted biosolids application. The repeated composted biosolids application increased soil NO(3)-N and NH(4)-N and decreased AB-DTPA extractable Ba as compared to the single composted biosolids application in 2004; differences between short- and long-term applications were less evident in 2005. Increasing biosolids rates resulted in increased native perennial grass cover in 2005. Plant tissue Cu, Mo, Zn, and P concentrations increased, while Ba content decreased depending on specific plant species and year. Overall, the lack of many significant negative effects suggests that short- or long-term composted biosolids application at the rates studied did not adversely affect this semi-arid grassland ecosystem. Published by Elsevier Ltd.
On the theory of Lorentz gases with long range interactions
NASA Astrophysics Data System (ADS)
Nota, Alessia; Simonella, Sergio; Velázquez, Juan J. L.
We construct and study the stochastic force field generated by a Poisson distribution of sources at finite density, x1,x2,…, in ℝ3 each of them yielding a long range potential QiΦ(x - xi) with possibly different charges Qi ∈ ℝ. The potential Φ is assumed to behave typically as |x|-s for large |x|, with s > 1/2. We will denote the resulting random field as “generalized Holtsmark field”. We then consider the dynamics of one tagged particle in such random force fields, in several scaling limits where the mean free path is much larger than the average distance between the scatterers. We estimate the diffusive time scale and identify conditions for the vanishing of correlations. These results are used to obtain appropriate kinetic descriptions in terms of a linear Boltzmann or Landau evolution equation depending on the specific choices of the interaction potential.
NASA Technical Reports Server (NTRS)
Ganguly, Sangram; Samanta, Arindam; Schull, Mitchell A.; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramajrushna R,; Knyazikhin, Yuri; Myneni, Ranga B.
2008-01-01
The evaluation of a new global monthly leaf area index (LAI) data set for the period July 1981 to December 2006 derived from AVHRR Normalized Difference Vegetation Index (NDVI) data is described. The physically based algorithm is detailed in the first of the two part series. Here, the implementation, production and evaluation of the data set are described. The data set is evaluated both by direct comparisons to ground data and indirectly through inter-comparisons with similar data sets. This indirect validation showed satisfactory agreement with existing LAI products, importantly MODIS, at a range of spatial scales, and significant correlations with key climate variables in areas where temperature and precipitation limit plant growth. The data set successfully reproduced well-documented spatio-temporal trends and inter-annual variations in vegetation activity in the northern latitudes and semi-arid tropics. Comparison with plot scale field measurements over homogeneous vegetation patches indicated a 7% underestimation when all major vegetation types are taken into account. The error in mean values obtained from distributions of AVHRR LAI and high-resolution field LAI maps for different biomes is within 0.5 LAI for six out of the ten selected sites. These validation exercises though limited by the amount of field data, and thus less than comprehensive, indicated satisfactory agreement between the LAI product and field measurements. Overall, the intercomparison with short-term LAI data sets, evaluation of long term trends with known variations in climate variables, and validation with field measurements together build confidence in the utility of this new 26 year LAI record for long term vegetation monitoring and modeling studies.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-07
... Comment request: Gulf Long-Term Follow-Up Study (GuLF STUDY) Summary: In compliance with the requirement... days of the date of this publication. Proposed Collection: Gulf Long-Term Follow-Up Study (GuLF STUDY... GuLF STUDY is to investigate potential short- and long-term health effects associated with oil spill...
Gravity Field Changes due to Long-Term Sea Level Changes
NASA Astrophysics Data System (ADS)
Makarynskyy, O.; Kuhn, M.; Featherstone, W. E.
2004-12-01
Long-term sea level changes caused by climatic changes (e.g. global warming) will alter the system Earth. This includes the redistribution of ocean water masses due to the migration of cold fresh water from formerly ice-covered regions to the open oceans mainly caused by the deglaciation of polar ice caps. Consequently also a change in global ocean circulation patterns will occur. Over a longer timescale, such mass redistributions will be followed by isostatic rebound/depression due to the changed surface un/loading, resulting in variable sea level change around the world. These, in turn, will affect the gravity field, location of the geocentre, and the Earth's rotation vector. This presentation focuses mainly on gravity field changes induced by long-term (hundredths to many thousand years) sea level changes using an Earth System Climate Model (ESCM) of intermediate complexity. In this study, the coupled University of Victoria (Victoria, Canada) Earth System Climate Model (Uvic ESCM) was used, which embraces the primary thermodynamic and hydrological components of the climate system including sea and land-ice information. The model was implemented to estimate changes in global precipitation, ocean mass redistribution, seawater temperature and salinity on timescales from hundreds to thousands years under different greenhouse warming scenarios. The sea level change output of the model has been converted into real mass changes by removing the steric effect, computed from seawater temperature and salinity information at different layers also provided by Uvic ESCM. Finally the obtained mass changes have been converted into changes of the gravitational potential and subsequently of the geoid height using a spherical harmonic representation of the different data. Preliminary numerical results are provided for sea level change as well as change in geoid height.
Zhang, Ming-kui; Ahmed Elgodah; Bao, Chen-yan
2014-12-01
Although a series of process techniques for treating wastewater from livestock and poultry breeding have been developed in China and overseas, it is still common in China's rural areas for utilization of the untreated wastewater to irrigate farmland directly because of economic reasons. The impact of untreated wastewater irrigation on accumulation and vertical migration of nitrogen and phosphorus in paddy soil is concerned. Consequently, four representative paddy fields with different histories of livestock farm wastewater irrigation (0, 4, 7, 13 years) were selected for collecting profile soil samples to study the effects of long-term irrigation of untreated livestock farm wastewater on various forms of nitrogen and phosphorus in the soils at different vertical depths. As compared with control field without any irrigation of wastewater, long-term irrigation of untreated livestock farm wastewater significantly increased the accumulation of N and P in the soils with increasing the irrigation year, and the increment of total P in the soil was greater than that of total N. Total P content in surface soil from fields with 4, 7, and 13 years irrigation was increased by 43.6%, 95.2%, and 148.4%, while total N increased by 7.6%, 16.9%, and 28.4%, respectively. Different forms of soil N were increased in order of NH4+ -N, NO3- -N > acid hydrolyzable N > non-acid hydrolyzable N, and soil available P changed much more than total P. Long-term irrigation of untreated livestock farm wastewater could promote vertical migration of soil nitrogen and phosphorus, and increase the pollution risk for groundwater.
Fedotova, Julia; Pivina, Svetlana; Sushko, Anastasia
2017-01-01
The present preclinical study was created to determine the therapeutic effects of vitamin D hormone treatment as an adjunctive therapy alone or in a combination with low dose of 17β-estradiol (17β-E2) on anxiety-like behavior in female rats with long-term absence of estrogen. Accordingly, the aim of the current study was to examine the effects of chronic cholecalciferol administration (1.0, 2.5 or 5.0 mg/kg subcutaneously, SC, once daily, for 14 days) on the anxiety-like state after long-term ovariectomy in female rats. Twelve weeks postovariectomy, cholecalciferol was administered to ovariectomized (OVX) rats and OVX rats treated with 17β-E2 (0.5 µg/rat SC, once daily, for 14 days). Anxiety-like behavior was assessed in the elevated plus maze (EPM) and the light/dark test (LDT), and locomotor and grooming activities were tested in the open field test (OFT). Cholecalciferol at two doses of 1.0 and 2.5 mg/kg alone or in combination with 17β-E2 produced anxiolytic-like effects in OVX rats as evidenced in the EPM and the LDT, as well as increased grooming activity in the OFT. Our results indicate that cholecalciferol, at two doses of 1.0 and 2.5 mg/kg, has a profound anxiolytic-like effects in the experimental rat model of long-term estrogen deficiency. PMID:28054941
Business Students' Choice of Short-Term or Long-Term Study Abroad Opportunities
ERIC Educational Resources Information Center
Fitzsimmons, Stacey R.; Flanagan, David J.; Wang, Xiaodan
2013-01-01
Recent years have seen a proliferation of short-term study abroad opportunities. Although they are both supplementing and replacing semester-long study abroad programs, research has focused primarily on semester (long-term) programs. We draw on the theory of planned behavior (TPB) to explore factors that predict why students choose long-term and…
Permanent field plot methodology and equipment
Thomas G. Cole
1993-01-01
Long-term research into the composition, phenology, yield, and growth rates of agroforests can be accomplished with the use of permanent field plots. The periodic remeasurement of these plots provides researchers a quantitative measure of what changes occur over time in indigenous agroforestry systems.
Long-term behavior of GFRP reinforced panels after eight years of field exposure.
DOT National Transportation Integrated Search
2014-06-01
Since 1998, Missouri S&T/University of Missouri-Rolla investigators have been involved in more than 25 bridge repairs and/or new : bridge construction involving composite materials. To date, many of these projects have demonstrated reliable field per...
Analysis of Decadal Vegetation Dynamics Using Multi-Scale Satellite Images
NASA Astrophysics Data System (ADS)
Chiang, Y.; Chen, K.
2013-12-01
This study aims at quantifying vegetation fractional cover (VFC) by incorporating multi-resolution satellite images, including Formosat-2(RSI), SPOT(HRV/HRG), Landsat (MSS/TM) and Terra/Aqua(MODIS), to investigate long-term and seasonal vegetation dynamics in Taiwan. We used 40-year NDVI records for derivation of VFC, with field campaigns routinely conducted to calibrate the critical NDVI threshold. Given different sensor capabilities in terms of their spatial and spectral properties, translation and infusion of NDVIs was used to assure NDVI coherence and to determine the fraction of vegetation cover at different spatio-temporal scales. Based on the proposed method, a bimodal sequence of intra-annual VFC which corresponds to the dual-cropping agriculture pattern was observed. Compared to seasonal VFC variation (78~90%), decadal VFC reveals moderate oscillations (81~86%), which were strongly linked with landuse changes and several major disturbances. This time-series mapping of VFC can be used to examine vegetation dynamics and its response associated with short-term and long-term anthropogenic/natural events.
Screen Violence and Youth Behavior.
Anderson, Craig A; Bushman, Brad J; Bartholow, Bruce D; Cantor, Joanne; Christakis, Dimitri; Coyne, Sarah M; Donnerstein, Edward; Brockmyer, Jeanne Funk; Gentile, Douglas A; Green, C Shawn; Huesmann, Rowell; Hummer, Tom; Krahé, Barbara; Strasburger, Victor C; Warburton, Wayne; Wilson, Barbara J; Ybarra, Michele
2017-11-01
Violence in screen entertainment media (ie, television, film, video games, and the Internet), defined as depictions of characters (or players) trying to physically harm other characters (or players), is ubiquitous. The Workgroup on Media Violence and Violent Video Games reviewed numerous meta-analyses and other relevant research from the past 60 years, with an emphasis on violent video game research. Consistent with every major science organization review, the Workgroup found compelling evidence of short-term harmful effects, as well as evidence of long-term harmful effects. The vast majority of laboratory-based experimental studies have revealed that violent media exposure causes increased aggressive thoughts, angry feelings, physiologic arousal, hostile appraisals, aggressive behavior, and desensitization to violence and decreases prosocial behavior (eg, helping others) and empathy. Still, to more fully understand the potential for long-term harm from media violence exposure, the field is greatly in need of additional large-sample, high-quality, longitudinal studies that include validated measures of media violence exposure and measures of other known violence risk factors. Also, although several high-quality media violence intervention studies have been conducted, larger-scale studies with more comprehensive and longer-term assessments are needed to fully understand long-term effects and to inform the development of tools that will help to reduce problems associated with aggression and violence. The evidence that violent screen media constitutes a causal risk factor for increased aggression is compelling. Modern social-cognitive theories of social behavior provide useful frameworks for understanding how and why these effects occur. Copyright © 2017 by the American Academy of Pediatrics.
Akatov, V V
2012-01-01
A review is presented of publications dealing with analysis of species richness of island biological communities and habitat islands based on the equilibrium theory of insular biogeography by MacArthur and Wilson (1963). Principal points of the theory are considered along with its shortcomings, problems and results of its testing. Also, possibilities are appraised for using recommendations elaborated on the base of the theory in nature conservation practice. The results of island and habitat island biota studies indicate that in many cases data corroborate the equilibrium theory while in many other cases they do not. In particular, for cenoses fragmented 50-250 years ago, especially for the ones formed by long living species, there have been no conspicuous effects of species relaxation detected. At that, the theory prediction of substantial reduction in species richness of fragmented communities in the long run is hardly disputed. The results of studies conducted in the field of insular biogeography are taken as a basis for recommendations on the long-term conservation of isolated communities integrity, although mostly they are of qualitative nature.
Ewald, Julie A; Wheatley, Christopher J; Aebischer, Nicholas J; Moreby, Stephen J; Duffield, Simon J; Crick, Humphrey Q P; Morecroft, Michael B
2015-11-01
Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long-term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long-term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long-term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change. © 2015 John Wiley & Sons Ltd.
Catchment-scale stormwater management via economic incentives – An overview and lessons-learned
Schuster, W.; Garmestani, A.S.; Green, O.O.; Rhea, l.K.; Roy, Allison; Thurston, H.W.; Myers, Baden Robert; Beecham, Simon; Lucke, Terry; Boogaard, Floris
2013-01-01
Long-term field studies of the effectiveness and sustainability of decentralized stormwater management are rare. From 2005-2011, we tested an incentive-based approach to citizen participation in stormwater management in the Shepherd Creek catchment, located in Cincinnati, OH, USA. Hydrologic, biological, and water quality data were characterized in a baseline monitoring effort 2005- 2007. Reverse auctions held successively in 2007 and 2008 engaged citizens to voluntarily bid on stormwater control measures (SCMs); and successful bids led to implementation of SCMs, which led to an enhancement of catchment detention capacity. We tested for attributes of sustainability (coconsideration of social, economic, and environmental (hydrologic, soils, aquatic biology) aspects), and summarize lessons-learned. Our results and outcomes provide a basis for planning future field studies that more fully determine the effectiveness of stormwater management in terms of sustainability.
Short-term high-altitude pre-exposure improves neurobehavioral ability
Guo, Wenyun; Chen, Guozhu; Qin, Jun; Zhang, Jihang; Guo, Xubin; Yu, Jie; Song, Pan; Lu, Wei; Xu, Baida; Li, Jiabei; Ding, Xiaohan
2016-01-01
This study aims to evaluate the effect of the duration of high-altitude (HA) pre-exposure on human neurobehavioral parameters including mood states and cognitive performance at HA. One hundred and eleven healthy individuals (ranging in age from 18 to 35 years) were recruited to participate in this study. They were divided into two groups: a 4-day short-term HA pre-exposure group (n=57) and a 3-month long-term HA pre-exposure group (n=54). All participants lived in the area at 400 m altitude above sea level before pre-exposure to HA. They were then transported to 3700 m plateau for either a 4-day or a 3-month HA pre-exposure, and finally delivered to 4400 m plateau. On the last day of pre-exposure at 3700 m and on the 10th day at 4400 m, neurobehavioral parameters of the participants in the two groups were evaluated. At the end of pre-exposure and on the 10th day of HA exposure, participants in the short-term group had significantly lower negative mood states, better cognitive performance with higher sensorimotor, attention, and psychomotor abilities, and less acute mountain sickness in comparison with the participants in the long-term pre-exposure group. Our field study with large samples showed that in comparison with 3-month long-term pre-exposure, 4-day short-term HA pre-exposure at 3700 m has a better effect in improving human neurobehavioral parameters including mood states and cognitive performance and reducing acute mountain sickness when exposed to a HA at 4400 m. PMID:26966781
NASA Technical Reports Server (NTRS)
Hammer, Philip D.; Valero, Francisco P. J.; Peterson, David L.; Smith, William Hayden
1991-01-01
The capabilities of the digital array scanned interferometer (DASI) class of instruments for measuring terrestrial radiation fields over the visible to mid-infrared are evaluated. DASI's are capable of high throughput, sensitivity and spectral resolution and have the potential for field-of-view spatial discrimination (an imaging spectrometer). The simplicity of design and operation of DASI's make them particularly suitable for field and airborne platform based remote sensing. The long term objective is to produce a versatile field instrument which may be applied toward a variety of atmospheric and surface studies. The operation of DASI and its advantages over other spectrometers are discussed.
Soil microbial C:N ratio is a robust indicator of soil productivity for paddy fields
NASA Astrophysics Data System (ADS)
Li, Yong; Wu, Jinshui; Shen, Jianlin; Liu, Shoulong; Wang, Cong; Chen, Dan; Huang, Tieping; Zhang, Jiabao
2016-10-01
Maintaining good soil productivity in rice paddies is important for global food security. Numerous methods have been developed to evaluate paddy soil productivity (PSP), most based on soil physiochemical properties and relatively few on biological indices. Here, we used a long-term dataset from experiments on paddy fields at eight county sites and a short-term dataset from a single field experiment in southern China, and aimed at quantifying relationships between PSP and the ratios of carbon (C) to nutrients (N and P) in soil microbial biomass (SMB). In the long-term dataset, SMB variables generally showed stronger correlations with the relative PSP (rPSP) compared to soil chemical properties. Both correlation and variation partitioning analyses suggested that SMB N, P and C:N ratio were good predictors of rPSP. In the short-term dataset, we found a significant, negative correlation of annual rice yield with SMB C:N (r = -0.99), confirming SMB C:N as a robust indicator for PSP. In treatments of the short-term experiment, soil amendment with biochar lowered SMB C:N and improved PSP, while incorporation of rice straw increased SMB C:N and reduced PSP. We conclude that SMB C:N ratio does not only indicate PSP but also helps to identify management practices that improve PSP.
Chen, Tao; Li, Qiang; Guo, Lina; Yu, Li; Li, Zhenyan; Guo, Huixin; Li, Haicheng; Zhao, Meigui; Chen, Liang; Chen, Xunxun; Zhong, Qiu; Zhou, Lin; Wu, Ting
2016-01-01
To overcome the undesirable side effects and reduce the cytotoxicity of isoniazid (INH) and rifampin (RMP) in the digestive tract, a poly(methacrylic acid) (PMAA) nanogel was developed as a carrier of INH and RMP. This PMAA/INH/RMP nanogel was prepared as a treatment for intestinal tuberculosis caused by multidrug-resistant Mycobacterium tuberculosis (MTB). The morphology, size, and in vitro release properties were evaluated in a simulated gastrointestinal medium, and long-term antibacterial performance, cytotoxicity, stability, and activity of this novel PMAA/INH/RMP nanogel against multidrug-resistant MTB in the intestine were investigated. Our results indicate that the PMAA/INH/RMP nanogel exhibited extended antibacterial activity by virtue of its long-term release of INH and RMP in the simulated gastrointestinal medium. Further, this PMAA/INH/RMP nanogel exhibited lower cytotoxicity than did INH or RMP alone, suggesting that this PMAA/INH/RMP nanogel could be a more useful dosage form than separate doses of INH and RMP for intestinal MTB. The novel aspects of this study include the cytotoxicity study and the three-phase release profile study, which might be useful for other researchers in this field. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Phenomenological Modeling and Laboratory Simulation of Long-Term Aging of Asphalt Mixtures
NASA Astrophysics Data System (ADS)
Elwardany, Michael Dawoud
The accurate characterization of asphalt mixture properties as a function of pavement service life is becoming more important as more powerful pavement design and performance prediction methods are implemented. Oxidative aging is a major distress mechanism of asphalt pavements. Aging increases the stiffness and brittleness of the material, which leads to a high cracking potential. Thus, an improved understanding of the aging phenomenon and its effect on asphalt binder chemical and rheological properties will allow for the prediction of mixture properties as a function of pavement service life. Many researchers have conducted laboratory binder thin-film aging studies; however, this approach does not allow for studying the physicochemical effects of mineral fillers on age hardening rates in asphalt mixtures. Moreover, aging phenomenon in the field is governed by kinetics of binder oxidation, oxygen diffusion through mastic phase, and oxygen percolation throughout the air voids structure. In this study, laboratory aging trials were conducted on mixtures prepared using component materials of several field projects throughout the USA and Canada. Laboratory aged materials were compared against field cores sampled at different ages. Results suggested that oven aging of loose mixture at 95°C is the most promising laboratory long-term aging method. Additionally, an empirical model was developed in order to account for the effect of mineral fillers on age hardening rates in asphalt mixtures. Kinetics modeling was used to predict field aging levels throughout pavement thickness and to determine the required laboratory aging duration to match field aging. Kinetics model outputs are calibrated using measured data from the field to account for the effects of oxygen diffusion and percolation. Finally, the calibrated model was validated using independent set of field sections. This work is expected to provide basis for improved asphalt mixture and pavement design procedures in order to save taxpayers' money.
NASA Astrophysics Data System (ADS)
Plaza, F.; Liang, X.; Wen, Y.; Perone, H.
2015-12-01
Acid mine drainage (AMD) is one of the most adverse environmental problems of the mine industry. Surface water and ground water affected by this pollution are characterized by their acidity and the high content of sulfates and heavy metals. In this study, alkaline clay, an industrial waste with a high pH, which is utilized in the alumina refining process, was used as the remediation material to inhibit pyrite oxidation. Through a series of batch and column experiments, complemented with field measurements and geochemical modeling, three important issues associated with this passive and auto sustainable acid mine drainage remediation method were investigated: 1) the potential use of alkaline clay as an AMD remediation material, 2) the adequate alkaline clay/coal refuse mixing ratio (AC/CR) to ensure pH values near to neutral conditions, and, 3) the prediction of long term impacts, in terms of the trends of the main parameters involved in this process such as pH, concentrations of sulfate, iron and other dissolved contaminants. Both field measurements and the samples used for the experiments came from a coal waste site located in Mather, Pennsylvania. Alkaline clay proved to be an effective remediation material for AMD. It was found that 10% AC/CR is an adequate mixing ratio (i.e. the upper limit), which has been also indicated by field measurements. The concentrations of some contaminants such as iron, manganese or sulfate are significantly reduced with the remediation approach, compared to those representative concentrations found in mine tailings. Moreover, results suggest a very reliable long-term stability of the remediation (i.e. neutral pH conditions are maintained), thus enhancing the generation of iron precipitates that could produce pyrite grain coating and hardpan (i.e. cemented layer) on the surface. These processes also made the amended layer less porous, thus increasing water retention and hindering oxygen diffusion.
Feng, Wenting; Liang, Junyi; Hale, Lauren E.; ...
2017-06-09
Quantifying soil organic carbon (SOC) decomposition under warming is critical to predict carbon–climate feedbacks. According to the substrate regulating principle, SOC decomposition would decrease as labile SOC declines under field warming, but observations of SOC decomposition under warming do not always support this prediction. This discrepancy could result from varying changes in SOC components and soil microbial communities under warming. This study aimed to determine the decomposition of SOC components with different turnover times after subjected to long-term field warming and/or root exclusion to limit C input, and to test whether SOC decomposition is driven by substrate lability under warming.more » Taking advantage of a 12-year field warming experiment in a prairie, we assessed the decomposition of SOC components by incubating soils from control and warmed plots, with and without root exclusion for 3 years. We assayed SOC decomposition from these incubations by combining inverse modeling and microbial functional genes during decomposition with a metagenomic technique (GeoChip). The decomposition of SOC components with turnover times of years and decades, which contributed to 95% of total cumulative CO 2 respiration, was greater in soils from warmed plots. But the decomposition of labile SOC was similar in warmed plots compared to the control. The diversity of C-degradation microbial genes generally declined with time during the incubation in all treatments, suggesting shifts of microbial functional groups as substrate composition was changing. Compared to the control, soils from warmed plots showed significant increase in the signal intensities of microbial genes involved in degrading complex organic compounds, implying enhanced potential abilities of microbial catabolism. These are likely responsible for accelerated decomposition of SOC components with slow turnover rates. Overall, the shifted microbial community induced by long-term warming accelerates the decomposition of SOC components with slow turnover rates and thus amplify the positive feedback to climate change.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Wenting; Liang, Junyi; Hale, Lauren E.
Quantifying soil organic carbon (SOC) decomposition under warming is critical to predict carbon–climate feedbacks. According to the substrate regulating principle, SOC decomposition would decrease as labile SOC declines under field warming, but observations of SOC decomposition under warming do not always support this prediction. This discrepancy could result from varying changes in SOC components and soil microbial communities under warming. This study aimed to determine the decomposition of SOC components with different turnover times after subjected to long-term field warming and/or root exclusion to limit C input, and to test whether SOC decomposition is driven by substrate lability under warming.more » Taking advantage of a 12-year field warming experiment in a prairie, we assessed the decomposition of SOC components by incubating soils from control and warmed plots, with and without root exclusion for 3 years. We assayed SOC decomposition from these incubations by combining inverse modeling and microbial functional genes during decomposition with a metagenomic technique (GeoChip). The decomposition of SOC components with turnover times of years and decades, which contributed to 95% of total cumulative CO 2 respiration, was greater in soils from warmed plots. But the decomposition of labile SOC was similar in warmed plots compared to the control. The diversity of C-degradation microbial genes generally declined with time during the incubation in all treatments, suggesting shifts of microbial functional groups as substrate composition was changing. Compared to the control, soils from warmed plots showed significant increase in the signal intensities of microbial genes involved in degrading complex organic compounds, implying enhanced potential abilities of microbial catabolism. These are likely responsible for accelerated decomposition of SOC components with slow turnover rates. Overall, the shifted microbial community induced by long-term warming accelerates the decomposition of SOC components with slow turnover rates and thus amplify the positive feedback to climate change.« less
Feng, Wenting; Liang, Junyi; Hale, Lauren E; Jung, Chang Gyo; Chen, Ji; Zhou, Jizhong; Xu, Minggang; Yuan, Mengting; Wu, Liyou; Bracho, Rosvel; Pegoraro, Elaine; Schuur, Edward A G; Luo, Yiqi
2017-11-01
Quantifying soil organic carbon (SOC) decomposition under warming is critical to predict carbon-climate feedbacks. According to the substrate regulating principle, SOC decomposition would decrease as labile SOC declines under field warming, but observations of SOC decomposition under warming do not always support this prediction. This discrepancy could result from varying changes in SOC components and soil microbial communities under warming. This study aimed to determine the decomposition of SOC components with different turnover times after subjected to long-term field warming and/or root exclusion to limit C input, and to test whether SOC decomposition is driven by substrate lability under warming. Taking advantage of a 12-year field warming experiment in a prairie, we assessed the decomposition of SOC components by incubating soils from control and warmed plots, with and without root exclusion for 3 years. We assayed SOC decomposition from these incubations by combining inverse modeling and microbial functional genes during decomposition with a metagenomic technique (GeoChip). The decomposition of SOC components with turnover times of years and decades, which contributed to 95% of total cumulative CO 2 respiration, was greater in soils from warmed plots. But the decomposition of labile SOC was similar in warmed plots compared to the control. The diversity of C-degradation microbial genes generally declined with time during the incubation in all treatments, suggesting shifts of microbial functional groups as substrate composition was changing. Compared to the control, soils from warmed plots showed significant increase in the signal intensities of microbial genes involved in degrading complex organic compounds, implying enhanced potential abilities of microbial catabolism. These are likely responsible for accelerated decomposition of SOC components with slow turnover rates. Overall, the shifted microbial community induced by long-term warming accelerates the decomposition of SOC components with slow turnover rates and thus amplify the positive feedback to climate change. © 2017 John Wiley & Sons Ltd.
Teaching long-term science investigations: A matter of talk, text, and time
NASA Astrophysics Data System (ADS)
Bills, Patricia Susan
Science educators regard long-term investigations as one impactful form of teaching science through inquiry in K-12 classrooms. While we have idealized notions of what this work looks like, we have few, if any, descriptive studies about investigations that engage students in sustained, focused work over a period of time longer than a few days or even weeks. In a policy context that calls for teachers to develop strategies for engaging students in authentic science practices, such as those that can come from long-term science investigations, we would do well to learn from experienced teachers. This study followed three middle school science teachers in a large U. S. urban school district as they conducted long-term investigations. Using discourse analysis and taking a sociocultural perspective, this study documented the classroom talk and interaction of teachers and their students. The study's goals were to describe how teachers engage students in long-term investigations and the ways that classroom interaction involved specific reform-based science practices. Data include field notes and transcripts of audio recordings from 15 observations of three experienced middle school science teachers, three semi-structured interviews with each teacher, curriculum materials, student work, and classroom demographic data. Teachers engaged students in whole group, small group, and one-on-one conversations about several stages of the long-term investigations. Teachers most often discussed two of the eight science practices: 1) planning and carrying out investigations; and 2) obtaining, evaluating, and communicating information. The planning discussions involved conversations about identifying and describing variables, measuring and recording data, and concerns about data collection procedures. Conversations about using and communicating scientific information included talk about formal science writing conventions, and using background information to support all other parts of the investigation process. In all of the observed lessons, regardless of the practice or types of investigations students were to engage, teachers used curricular tools to support students' work, scaffolding students' introduction to and use of scientific content, practices, and discourse. In these ways, teachers helped students master a science-specific vocabulary and set of practices that allow for the authentic exploration of science concepts. This study describes how teachers who generate opportunities for students to experience two science practices more often than others, which may have implications for science education and science education research - especially concerning how science practices are engaged in classrooms - moving forward.
Macroion solutions in the cell model studied by field theory and Monte Carlo simulations.
Lue, Leo; Linse, Per
2011-12-14
Aqueous solutions of charged spherical macroions with variable dielectric permittivity and their associated counterions are examined within the cell model using a field theory and Monte Carlo simulations. The field theory is based on separation of fields into short- and long-wavelength terms, which are subjected to different statistical-mechanical treatments. The simulations were performed by using a new, accurate, and fast algorithm for numerical evaluation of the electrostatic polarization interaction. The field theory provides counterion distributions outside a macroion in good agreement with the simulation results over the full range from weak to strong electrostatic coupling. A low-dielectric macroion leads to a displacement of the counterions away from the macroion. © 2011 American Institute of Physics
OK-432 sclerotherapy in head and neck lymphangiomas: long-term follow-up result.
Yoo, Jae Chul; Ahn, Youngjin; Lim, Yune Syung; Hah, J Hun; Kwon, Tack-Kyun; Sung, Myung-Whun; Kim, Kwang Hyun
2009-01-01
Nonsurgical treatments, such as sclerotherapy have been attempted for head and neck lymphagiomas. Of the available sclerosing agents, picibanil has shown satisfactory short-term treatment results in many studies, but no study has presented long-term treatment results. Accordingly, in the present study, the authors retrospectively reviewed the long-term treatment results of picibanil sclerotherapy. Fifty-five lymphangioma patients who underwent picibanil sclerotherapy were enrolled. Data about initial and long-term response, recurrence, and excision rate were collected. Initial response rates were 83.5 percent and long-term response rates were 76.3 percent. Initial and the long-term response rate were equally good for lymphangioma.
Kawaguchi, Hideaki; Taguchi, Masamoto; Sukigara, Masune; Sakuragi, Shoji; Sugiyama, Naoya; Chiba, Hisomu; Kawasaki, Tatsuhito
2017-06-15
We comprehensively evaluated cognitive and social functioning in patients requiring long-term inpatient psychiatric care using the International Classification of Functioning, Disability, and Health. We surveyed 1967 patients receiving long-term inpatient psychiatric care. Patients were further categorized into an old long-stay group (n = 892, >5 years in hospitals) and a new long-stay group (n = 1075, 1-5 years in hospitals). We obtained responses for all the International Classification of Functioning, Disability, and Health items in domain b (Body Functions) and domain d (Activities and Participation). We estimated weighted means for each item using the propensity score to adjust for confounding factors. Responses were received from 307 hospitals (response rate of hospitals: 25.5%). Cognitive and social functioning in the old long-stay group was more severely impaired than in the new long-stay group. No statistically significant differences were observed regarding the International Classification of Functioning, Disability, and Health items associated with basic activities of daily living between the two groups. Combined therapy consisting of cognitive remediation and rehabilitation on social functioning for this patient population should be started from the early stage of hospitalization. Non-restrictive, independent environments may also be optimal for this patient population. Implications for rehabilitation Rehabilitation of cognitive and social functioning for patients requiring long-term inpatient psychiatric care should be started in the early stages of hospitalization. In psychiatric fields, the International Classification of Functioning, Disability, and Health checklist could facilitate individualized rehabilitation planning by allowing healthcare professionals to visually assess the comprehensive functioning of each patient using graphics such as radar charts.
Holeck, K. T.; Rudstam, L. G.; Watkins, J. M.; Luckey, F. J.; Lantry, J. R.; Lantry, Brian F.; Trometer, E. S.; Koops, M. A.; Johnson, Terry B.
2015-01-01
Phosphorus loading declined between the 1970s and the 1990s, leading to oligotrophication of the offshore waters of Lake Ontario during that time period. Using lake-wide data from the intensive field years of 2003 and 2008 and from available long-term data sets on several trophic state indicators (total phosphorus [TP], soluble reactive silica [SRSi], chlorophyll a and Secchi disc transparency [SDT]), we tested the hypothesis that oligotrophication of the offshore waters of Lake Ontario has continued in the 2000s. Significant differences between 2003 and 2008 include higher spring (April) TP, SRSi, and SDT in 2008, lower summer (July–August) SDT in 2008, higher summer chlorophyll a in 2008, and lower fall (September) TP, SRSi, and chlorophyll a in 2008. The decline in SRSi from spring to summer was greater in 2008 than in 2003. Change point and regression analyses on the long-term data revealed no trend in spring TP since 1996, in summer chlorophyll a since 1994, in spring SDT since 1998, in spring SRSi or SRSi decline from spring to summer since 1999, or in summer SDT since 2001. Neither the comparison of the 2003 and 2008 surveys nor the analysis of the long-term data supported our hypothesis of continued oligotrophication of the offshore of Lake Ontario in the 2000s.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Won, Jong-Pil, E-mail: jpwon@konkuk.ac.kr; Hwang, Un-Jong; Lee, Su-Jin
This study evaluated the performance of shotcrete using high strength C{sub 12}A{sub 7} mineral-based accelerator that has been developed to improve the durability and long-term strength. Rebound, compressive strength and flexural strength were tested in the field. Test result showed that existing C{sub 12}A{sub 7} mineral-based accelerator exhibits better early strength than the high-strength C{sub 12}A{sub 7} mineral-based accelerator until the early age, but high-strength C{sub 12}A{sub 7} mineral-based accelerator shows about 29% higher at the long-term age of 28 days. Microstructural analysis such as scanning electron microscope (SEM), X-ray diffraction (XRD) and nitrogen adsorption method was evaluated to analyzemore » long-term strength development mechanism of high strength C{sub 12}A{sub 7} mineral-based accelerator. As analysis result, it had more dense structure due to the reaction product by adding material that used to enhanced strength. It had better resistance performance in chloride ion penetration, freezing–thawing and carbonation than shotcrete that used existing C{sub 12}A{sub 7} mineral-based accelerator.« less
Manselle, Wayne; Woollacott, Marjorie H.
2014-01-01
Abstract This cross-sectional field study documented the effect of long-term t'ai chi, meditation, or aerobic exercise training versus a sedentary lifestyle on executive function. It was predicted that long-term training in t'ai chi and meditation plus exercise would produce greater benefits to executive function than aerobic exercise. T'ai chi and meditation plus exercise include mental and physical training. Fifty-four volunteers were tested: t'ai chi (n=10); meditation+exercise (n=16); aerobic exercisers (n=16); and sedentary controls (n=12). A one-factor (group), one-covariate (age) multivariate analysis of covariance was performed. Significant main effects of group and age were found (group, 67.9%, p<0.001; age, 76.3%, p=0.001). T'ai chi and meditation practitioners but not aerobic exercisers outperformed sedentary controls on percent switch costs (p=0.001 and p=0.006, respectively), suggesting that there may be differential effects of training type on executive function. PMID:24286339
Cognition in epilepsy: current clinical issues of interest.
Witt, Juri-Alexander; Helmstaedter, Christoph
2017-04-01
This review provides an update and summary of recent neuropsychological findings in epilepsy focusing on three major clinical topics among the many developments in the field. We will critically outline the current state with regard to cognition in new-onset epilepsies, social cognition in epilepsy, and the long-term outcome of epilepsy surgery and the cognitive outcomes of superselective surgical procedures. Current studies indicate that neuropsychological impairments are prevalent already at the onset of epilepsy and even before, social cognition (i.e., emotion recognition and theory of mind) is impaired in different epilepsy populations, the long-term outcome of epilepsy surgery is mostly characterized by a stable or even improved cognitive status, and superselective epilepsy surgeries are associated with a promising neuropsychological outcome. The high prevalence of cognitive deficits around epilepsy onset challenges the assumption that epilepsy is the major cause of cognitive problems and calls for early neuropsychological diagnostics. Social cognition seems to be a relevant domain that is not yet routinely considered in epilepsy. The cognitive long-term outcome of epilepsy surgery is mostly positive. Stereotactic thermocoagulation and gamma knife surgery appear to be cognitively safe procedures.
Performance limiting processes in room temperature thallium bromide radiation detectors
NASA Astrophysics Data System (ADS)
Datta, Amlan; Becla, Piotr; Moed, Demi; Motakef, Shariar
2015-09-01
Thallium Bromide (TlBr) is a promising room-temperature radiation detector candidate with excellent charge transport properties. However, several critical issues are needed to be addressed before deployment of this material for long-term field applications. In this paper, the relevance and, scientific and technological progress made towards solving these challenges for TlBr have been discussed. The possible research pathways to mitigate the concerns related to this material have been analyzed and clearly established. Findings from novel experiments performed at CapeSym have revealed that the most significant factors for achieving long-term performance stability for TlBr devices involve physical and chemical conditions of the surface, residual stress, and choice of metal contacts. Palladium electrodes on TlBr devices resulted in a 20-fold improvement in the device lifetime when compared to its Br-etched Pt counterpart. Electron and hole contributions towards the spectroscopic response of the TlBr detector significantly depend on the interaction position of the incoming radiation and was clearly observed in this study. TlBr device fabrication techniques need significant improvement in order to attain reliable, repeatable, and stable, long-term performance.
NASA Astrophysics Data System (ADS)
Alconcel, L. N. S.; Fox, P.; Brown, P.; Oddy, T. M.; Lucek, E. L.; Carr, C. M.
2014-07-01
Over the course of more than 10 years in operation, the calibration parameters of the outboard fluxgate magnetometer (FGM) sensors on the four Cluster spacecraft are shown to be remarkably stable. The parameters are refined on the ground during the rigorous FGM calibration process performed for the Cluster Active Archive (CAA). Fluctuations in some parameters show some correlation with trends in the sensor temperature (orbit position). The parameters, particularly the offsets, of the spacecraft 1 (C1) sensor have undergone more long-term drift than those of the other spacecraft (C2, C3 and C4) sensors. Some potentially anomalous calibration parameters have been identified and will require further investigation in future. However, the observed long-term stability demonstrated in this initial study gives confidence in the accuracy of the Cluster magnetic field data. For the most sensitive ranges of the FGM instrument, the offset drift is typically 0.2 nT per year in each sensor on C1 and negligible on C2, C3 and C4.
NASA Astrophysics Data System (ADS)
Alconcel, L. N. S.; Fox, P.; Brown, P.; Oddy, T. M.; Lucek, E. L.; Carr, C. M.
2014-01-01
Over the course of more than ten years in operation, the calibration parameters of the outboard fluxgate magnetometer (FGM) sensors on the four Cluster spacecraft are shown to be remarkably stable. The parameters are refined on the ground during the rigorous FGM calibration process performed for the Cluster Active Archive (CAA). Fluctuations in some parameters show some correlation with trends in the sensor temperature (orbit position). The parameters, particularly the offsets, of the Spacecraft1 (C1) sensor have undergone more long-term drift than those of the other spacecraft (C2, C3 and C4) sensors. Some potentially anomalous calibration parameters have been identified and will require further investigation in future. However, the observed long-term stability demonstrated in this initial study gives confidence in the relative accuracy of the Cluster magnetic field data. For the most sensitive ranges of the FGM instrument, the offset drift is typically 0.2 nT yr-1 in each sensor on C1 and negligible on C2, C3 and C4.
Charles E. Swift; Kerri T. Vierling; Andrew T. Hudak; Lee A. Vierling
2017-01-01
Ecologists have a long-term interest in understanding the relative influence of vegetation composition and vegetation structure on avian diversity. LiDAR remote sensing is useful in studying local patterns of avian diversity because it characterizes fine-scale vegetation structure across broad extents. We used LiDAR, aerial and satellite imagery, and avian field data...
Research Priorities for Dance Education: A Report to the Nation
ERIC Educational Resources Information Center
Bonbright, Jane M.; Bradley, Karen K.; Bucek, Loren; Faber, Rima; Gibb, Sara Lee; Hagood, Thomas K.; Koff, Susan; Press, Carol M.
2004-01-01
The Research in Dance Education (RDE) project grew out of a long-term national need to know what researchers in dance and allied fields have studied over 80 years, what they learned, and how existing research impacted teaching and learning. The project set out to answer the following questions: (1) What research exists in dance education?; (2)…
Short- and Long-Term Musical Preferences: What Makes a Favourite Piece of Music?
ERIC Educational Resources Information Center
Lamont, Alexandra; Webb, Rebecca
2010-01-01
Within the growing field of music preferences, little is currently known about the concept of a favourite piece of music. The current study explores listeners' nominated favourite pieces of music over short and longer time-spans, combining diary and interview methods to uncover what a favourite means, how stable it is, and what factors influence…
Viewing Forests Through a Historical Lens
Noreen Parks; Eric [< em> featured scientist< /em> ] Knapp
2009-01-01
Past records on fire-resilient, biodiverse stands could offer models for the future. This year marks the centennial of the Forest Serviceâs nationwide network of 80 experimental forests and ranges, which serve as field laboratories for long-term studies on the science and management of national forests. At the Stanislaus-Tuolumne Experimental Forest in the central...
The Fry Canyon site in southeastern Utah was selected in 1996 as a long-term field demonstration site to assess the performance of selected permeable reactive barriers for the removal of uranium (U) from groundwater.
Linking Fine-Scale Observations and Model Output with Imagery at Multiple Scales
NASA Astrophysics Data System (ADS)
Sadler, J.; Walthall, C. L.
2014-12-01
The development and implementation of a system for seasonal worldwide agricultural yield estimates is underway with the international Group on Earth Observations GeoGLAM project. GeoGLAM includes a research component to continually improve and validate its algorithms. There is a history of field measurement campaigns going back decades to draw upon for ways of linking surface measurements and model results with satellite observations. Ground-based, in-situ measurements collected by interdisciplinary teams include yields, model inputs and factors affecting scene radiation. Data that is comparable across space and time with careful attention to calibration is essential for the development and validation of agricultural applications of remote sensing. Data management to ensure stewardship, availability and accessibility of the data are best accomplished when considered an integral part of the research. The expense and logistical challenges of field measurement campaigns can be cost-prohibitive and because of short funding cycles for research, access to consistent, stable study sites can be lost. The use of a dedicated staff for baseline data needed by multiple investigators, and conducting measurement campaigns using existing measurement networks such as the USDA Long Term Agroecosystem Research network can fulfill these needs and ensure long-term access to study sites.
Everaert, Joris; Bauwens, Dirk
2007-01-01
A possible effect of long-term exposure to low-intensity electromagnetic radiation from mobile phone (GSM) base stations on the number of House Sparrows during the breeding season was studied in six residential districts in Belgium. We sampled 150 point locations within the 6 areas to examine small-scale geographic variation in the number of House Sparrow males and the strength of electromagnetic radiation from base stations. Spatial variation in the number of House Sparrow males was negatively and highly significantly related to the strength of electric fields from both the 900 and 1800 MHz downlink frequency bands and from the sum of these bands (Chi(2)-tests and AIC-criteria, P<0.001). This negative relationship was highly similar within each of the six study areas, despite differences among areas in both the number of birds and radiation levels. Thus, our data show that fewer House Sparrow males were seen at locations with relatively high electric field strength values of GSM base stations and therefore support the notion that long-term exposure to higher levels of radiation negatively affects the abundance or behavior of House Sparrows in the wild.
Liu, Haiyang; Li, Jia; Zhao, Yan; Xie, Kexin; Tang, Xianjin; Wang, Shaoxian; Li, Zhongpei; Liao, Yulin; Xu, Jianming; Di, Hongjie; Li, Yong
2018-08-15
Nitrification plays an important role in the soil nitrogen (N) cycle, and fertilizer application may influence soil nitrifiers' abundance and composition. However, the effect of long-term manure application in paddy soils on nitrifying populations is poorly understood. We chose four long-term manure experimental fields in the south of China to study how the abundance and community structure of nitrifiers would change in response to long-term manure application using quantitative PCR and Miseq sequencing analyses. Our results showed that manure application significantly increased ammonia oxidizing archaea (AOA) abundance at the ChangSha (CS) and NanChang (NC) sites, while the abundance of ammonia oxidizing bacteria (AOB) represented 4.8- and 12.8- fold increases at the JiaXing (JX) and YingTan (YT) sites, respectively. Miseq sequencing of 16S rRNA genes indicated that manure application altered the community structure of nitrifying populations, especially at the NC and YT sites. The application of manure significantly changed AOA and nitrite oxidizing bacteria (NOB) community structures but not those of AOB, suggesting that AOA and NOB may be more sensitive to manures. Variation partitioning analysis (VPA) and redundancy analysis (RDA) indicated that soil pH, TN, NO 3 - -N and water content were the main factors in shaping nitrifying communities. These findings suggest that nitrifiers respond diversely to manure application, and soil physiochemical properties play an important role in determining nitrifiers' abundance and communities with long-term manure addition. Copyright © 2018 Elsevier B.V. All rights reserved.
Bérard, Annette; Capowiez, Line; Mombo, Stéphane; Schreck, Eva; Dumat, Camille; Deola, Frédéric; Capowiez, Yvan
2016-03-01
We performed a field investigation to study the long-term impacts of Pb soil contamination on soil microbial communities and their catabolic structure in the context of an industrial site consisting of a plot of land surrounding a secondary lead smelter. Microbial biomass, catabolic profiles, and ecotoxicological responses (PICT) were monitored on soils sampled at selected locations along 110-m transects established on the site. We confirmed the high toxicity of Pb on respirations and microbial and fungal biomasses by measuring positive correlations with distance from the wall factory and negative correlation with total Pb concentrations. Pb contamination also induced changes in microbial and fungal catabolic structure (from carbohydrates to amino acids through carboxylic malic acid). Moreover, PICT measurement allowed to establish causal linkages between lead and its effect on biological communities taking into account the contamination history of the ecosystem at community level. The positive correlation between qCO2 (based on respiration and substrate use) and PICT suggested that the Pb stress-induced acquisition of tolerance came at a greater energy cost for microbial communities in order to cope with the toxicity of the metal. In this industrial context of long-term polymetallic contamination dominated by Pb in a field experiment, we confirmed impacts of this metal on soil functioning through microbial communities, as previously observed for earthworm communities.
Ezerarslan, Hande; Beriat, Güçlü Kaan; Nurhat, Raziye Handan; Kazancı, Burak; Çelikkan, Ferda Topal; Sabuncuoğlu, Bizden; Sabuncuoğlu, Hakan
2016-08-01
We aimed to find out the effects of short term and long term hydrocephalus and intracranial ventricular volume changes on cochlear functions by using distortion product otoacoustic emission (DPOAE) in experimental hydrocephalus rat models for the first time in literature. This study was performed with 48 healthy, adult (8 weeks old), Sprague-Dawley rats which weighed between 200 and 240g. Six groups were formed in this study: short term control, short term sham, short term hydrocephalus, long term control, long term sham and long term hydrocephalus groups. Each group contained eight rats. Short term period was 4 weeks and long term period was 8 weeks after the study started. At the end of these periods, DPOAE measurements were performed and then rats were sacrificed to determine ventricular volumes. DPOAE values at all frequencies were significantly decreased in the short term hydrocephalus group when compared to the short term control and short term sham groups. DPOAE values at all frequencies were significantly decreased in the long term hydrocephalus group when compared to the long term control and long term sham groups. Besides, long term sham group which had higher ventricular volumes than long term control group also had lower DPOAE measurements. Significant associations were present between DPOAE measurements and ventricular volumes in hydrocephalus models. The functional disturbances in cochlear functions due to hydrocephalus have been demonstrated with DPOAE measurements in this study. DPOAE measurements may be thought as an easily applicable non-invasive method in detection and follow-up of patients with hydrocephalus. Our findings should be supported with clinical studies in humans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Host-pathogen interactions and bacterial survival under phage fluctuations
NASA Astrophysics Data System (ADS)
Skanata, Antun; Kussell, Edo
Environmental changes can have profound effects on ecosystems, leading to drastic outcomes such as extinction and desertification. Quantifying, predicting, and ultimately preventing those transitions is a key problem in the field. Our previous work in microbial systems has shown that fluctuations in environments drive transitions to alternate evolutionary optima, which can be either smooth or abrupt. The long term growth rate, an analog of free energy for population dynamics, has been used to distinguish under what conditions those transitions will occur. Our framework, which uses the mean field approximation to compute the long term growth rate in fluctuating environments, is uniquely positioned to treat more complex dependencies that allow coexistence among species sharing resources or infected by common pathogens. Here we present a simple model of a bacterial community subjected to fluctuating phage infections that outlines the regimes where species diversity results in long-term stability. We identify prevalent, but often counter-intuitive, strategies that bacteria use to protect against infection, and find a new general principle in the evolution of phage resistance. Our results, which predict the transition regimes, have implications for a broad range of ecological models.
NASA Astrophysics Data System (ADS)
Perez-Poch, Antoni
Computer simulations are becoming a promising research line of work, as physiological models become more and more sophisticated and reliable. Technological advances in state-of-the-art hardware technology and software allow nowadays for better and more accurate simulations of complex phenomena, such as the response of the human cardiovascular system to long-term exposure to microgravity. Experimental data for long-term missions are difficult to achieve and reproduce, therefore the predictions of computer simulations are of a major importance in this field. Our approach is based on a previous model developed and implemented in our laboratory (NELME: Numercial Evaluation of Long-term Microgravity Effects). The software simulates the behaviour of the cardiovascular system and different human organs, has a modular archi-tecture, and allows to introduce perturbations such as physical exercise or countermeasures. The implementation is based on a complex electrical-like model of this control system, using inexpensive development frameworks, and has been tested and validated with the available experimental data. The objective of this work is to analyse and simulate long-term effects and gender differences when individuals are exposed to long-term microgravity. Risk probability of a health impairement which may put in jeopardy a long-term mission is also evaluated. . Gender differences have been implemented for this specific work, as an adjustment of a number of parameters that are included in the model. Women versus men physiological differences have been therefore taken into account, based upon estimations from the physiology bibliography. A number of simulations have been carried out for long-term exposure to microgravity. Gravity varying continuosly from Earth-based to zero, and time exposure are the two main variables involved in the construction of results, including responses to patterns of physical aerobic ex-ercise and thermal stress simulating an extra-vehicular activity. Results show that significant differences appear between men and women physiological response after long-term exposure (more than three months) to microgravity. Risk evaluation for every gender, and specific risk thresholds are provided. Different scenarios like a long-term mission to Moon or Mars are evaluated, including countermeasures such as aerobic exercise. Initial results are compatible with the existing data, and provide useful insights regarding different patterns of microgravity exposure. We conclude that computer-based models such us NELME are a promising line of work to predict health risks in long-term missions.
Wolf, M M; Braukmann, C J; Ramp, K A
1987-01-01
The past 20 years have been productive ones for the field of applied behavior analysis. A brief review of our own efforts during this period reveals that we have accomplished several but not all of our goals for the Teaching-Family approach. In this context, we note that the setting of realistic and appropriate goals is important for the field and for society. Moreover, we suggest that the realistic goal for some persons with serious delinquent behavior may be extended supportive and socializing treatment rather than permanent cure from conventional short-term treatment programs. We base this suggestion on the accumulating evidence that serious delinquent behavior may often be part of a significantly disabling and durable condition that consists of multiple antisocial and dysfunctional behaviors, often runs in families, and robustly eludes effective short-term treatment. Like other significant disabilities such as retardation, autism, and blindness, the effects of this condition may be a function of an interaction of environmental and constitutional variables. We argue that our field has the wherewithal to construct effective and humane long-term supportive environments for seriously delinquent youths. In this regard, we explore the dimensions, rationales, logistics, and beginnings of a new treatment direction that involves long-term supportive family treatment. We contend that such supportive families may be able to provide long, perhaps even lifetime, socializing influences through models, values, and contingencies that seem essential for developing and maintaining prosocial behavior in these high-risk youths. PMID:3323156
Gur, Rotem; Tendler, Alex; Wagner, Shlomo
2014-09-01
Recognition of specific individuals is fundamental to mammalian social behavior and is mediated in most mammals by the main and accessory olfactory systems. Both these systems innervate the medial amygdala (MeA), where activity of the neuropeptide oxytocin is thought to mediate social recognition memory (SRM). The specific contribution of the MeA to SRM formation and the specific actions of oxytocin in the MeA are unknown. We used the social discrimination test to evaluate short-term and long-term SRM in adult Sprague-Dawley male rats (n = 38). The role of protein synthesis in the MeA was investigated by local application of the protein synthesis blocker anisomycin (n = 11). Synaptic plasticity was assessed in vivo by recording the MeA evoked field potential responses to stimulation of the main (n = 21) and accessory (n = 56) olfactory bulbs before and after theta burst stimulation. Intracerebroventricular administration of saline, oxytocin, or oxytocin receptor antagonist was used to measure the effect of oxytocin on synaptic plasticity. Anisomycin application to the MeA prevented the formation of long-term SRM. In addition, the responses of MeA neurons underwent long-term depression (LTD) after theta burst stimulation of the accessory olfactory bulb, but not the main accessory bulb, in an oxytocin-dependent manner. No LTD was found in socially isolated rats, which are known to lack long-term SRM. Finally, accessory olfactory bulb stimulation before SRM acquisition blocked long-term SRM, supporting the involvement of LTD in the MeA in formation of long-term SRM. Our results indicate that long-term SRM in rats involves protein synthesis and oxytocin-dependent LTD in the MeA. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Measure-valued solutions to nonlocal transport equations on networks
NASA Astrophysics Data System (ADS)
Camilli, Fabio; De Maio, Raul; Tosin, Andrea
2018-06-01
Aiming to describe traffic flow on road networks with long-range driver interactions, we study a nonlinear transport equation defined on an oriented network where the velocity field depends not only on the state variable but also on the distribution of the population. We prove existence, uniqueness and continuous dependence results of the solution intended in a suitable measure-theoretic sense. We also provide a representation formula in terms of the push-forward of the initial and boundary data along the network and discuss an explicit example of nonlocal velocity field fitting our framework.
Thermal interaction of the core and the mantle and long-term behavior of the geomagnetic field
NASA Technical Reports Server (NTRS)
Jones, G. M.
1977-01-01
The effects of temperature changes at the earth's core-mantle boundary on the velocity field of the core are analyzed. It is assumed that the geomagnetic field is maintained by thermal convection in the outer core. A model for the thermal interaction of the core and the mantle is presented which is consistent with current views on the presence of heat sources in the core and the properties of the lower mantle. Significant long-term variations in the frequency of geomagnetic reversals may be the result of fluctuating temperatures at the core-mantle boundary, caused by intermittent convection in the lower mantle. The thermal structure of the lower mantle region D double prime, extending from 2700 to 2900 km in depth, constitutes an important test of this hypothesis and offers a means of deciding whether the geomagnetic dynamo is thermally driven.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Male, E.J.; Pickles, W.L.; Silver, E.A.
2009-11-01
Hyperspectral plant signatures can be used as a short-term, as well as long-term (100-yr timescale) monitoring technique to verify that CO2 sequestration fields have not been compromised. An influx of CO2 gas into the soil can stress vegetation, which causes changes in the visible to nearinfrared reflectance spectral signature of the vegetation. For 29 days, beginning on July 9th, 2008, pure carbon dioxide gas was released through a 100-meter long horizontal injection well, at a flow rate of 300 kg/day. Spectral signatures were recorded almost daily from an unmown patch of plants over the injection with a ''FieldSpec Pro'' spectrometermore » by Analytical Spectral Devices, Inc. Measurements were taken both inside and outside of the CO2 leak zone to normalize observations for other environmental factors affecting the plants.« less
Zhou, Shuang-Xi; Medlyn, Belinda E; Prentice, Iain Colin
2016-01-01
Experimental drought is well documented to induce a decline in photosynthetic capacity. However, if given time to acclimate to low water availability, the photosynthetic responses of plants to low soil moisture content may differ from those found in short-term experiments. This study aims to test whether plants acclimate to long-term water stress by modifying the functional relationships between photosynthetic traits and water stress, and whether species of contrasting habitat differ in their degree of acclimation. Three Eucalyptus taxa from xeric and riparian habitats were compared with regard to their gas exchange responses under short- and long-term drought. Photosynthetic parameters were measured after 2 and 4 months of watering treatments, namely field capacity or partial drought. At 4 months, all plants were watered to field capacity, then watering was stopped. Further measurements were made during the subsequent 'drying-down', continuing until stomata were closed. Two months of partial drought consistently reduced assimilation rate, stomatal sensitivity parameters (g1), apparent maximum Rubisco activity (V'(cmax)) and maximum electron transport rate (J'(max)). Eucalyptus occidentalis from the xeric habitat showed the smallest decline in V'(cmax) and J'(max); however, after 4 months, V'(cmax) and J'(max) had recovered. Species differed in their degree of V'(cmax) acclimation. Eucalyptus occidentalis showed significant acclimation of the pre-dawn leaf water potential at which the V'(cmax) and 'true' V(cmax) (accounting for mesophyll conductance) declined most steeply during drying-down. The findings indicate carbon loss under prolonged drought could be over-estimated without accounting for acclimation. In particular, (1) species from contrasting habitats differed in the magnitude of V'(cmax) reduction in short-term drought; (2) long-term drought allowed the possibility of acclimation, such that V'(cmax) reduction was mitigated; (3) xeric species showed a greater degree of V'(cmax) acclimation; and (4) photosynthetic acclimation involves hydraulic adjustments to reduce water loss while maintaining photosynthesis. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Schwab, Michael; Klaus, Julian; Pfister, Laurent; Weiler, Markus
2016-04-01
Over the past decades, stream sampling protocols for hydro-geochemical parameters were often limited by logistical and technological constraints. While long-term monitoring protocols were typically based on weekly sampling intervals, high frequency sampling was commonly limited to a few single events. In our study, we combined high frequency and long-term measurements to understand the DOC and nitrate behaviour and dynamics for different runoff events and seasons. Our study area is the forested Weierbach catchment (0.47 km2) in Luxembourg. The fractured schist bedrock is covered by cambisol soils. The runoff response of the catchment is characterized by a double peak behaviour. A first discharge peak occurs during or right after a rainfall event (triggered by fast near surface runoff generation processes), while a second delayed peak lasts several days (generated by subsurface flow/ shallow groundwater flow). Peaks in DOC concentrations are closely linked to the first discharge peak, whereas nitrate concentrations follow the second peak. Our observations were carried out with the field deployable instrument spectro::lyser (scan Messtechnik GmbH). This instrument relies on the principles of UV-Vis spectrometry and measures DOC and nitrate concentrations. The measurements were carried out at a high frequency of 15 minutes in situ in the Weierbach creek for more than two years. In addition, a long-term validation was carried out with data obtained from the analysis of water collected with automatic samplers. The long-term, high-frequency measurements allowed us to calculate a complete and detailed balance of DOC and nitrate export over two years. Transport behaviour of the DOC and nitrate showed different dynamics between the first and second hydrograph peaks. DOC is mainly exported during first peaks, while nitrate is mostly exported during the delayed second peaks. In combination with other measurements in the catchment, the long and detailed observations have enabled us to derive relationships between DOC and nitrate export and different catchment states: soil wetness and groundwater levels, precipitation and seasonality. Altogether, the long-term and high-frequency time series provides the opportunity to study DOC and nitrate export without having to just rely only on either a few single event measurements or coarse measurement protocols.
NASA Technical Reports Server (NTRS)
Gomberg, Joan; Ellis, Michael
1994-01-01
We present results of a series of numerical experiments designed to test hypothetical mechanisms that derive deformation in the New Madrid seismic zone. Experiments are constrained by subtle topography and the distribution of seismicity in the region. We use a new boundary element algorithm that permits calcuation of the three-dimensional deformation field. Surface displacement fields are calculated for the New Madrid zone under both far-field (plate tectonics scale) and locally derived driving strains. Results demonstrate that surface displacement fields cannot distinguish between either a far-field simple or pure shear strain field or one that involves a deep shear zone beneath the upper crustal faults. Thus, neither geomorphic nor geodetic studies alone are expected to reveal the ultimate driving mechanism behind the present-day deformation. We have also tested hypotheses about strain accommodation within the New Madrid contractional step-over by including linking faults, two southwest dipping and one vertical, recently inferred from microearthquake data. Only those models with step-over faults are able to predict the observed topography. Surface displacement fields for long-term, relaxed deformation predict the distribution of uplift and subsidence in the contractional step-over remarkably well. Generation of these displacement fields appear to require slip on both the two northeast trending vertical faults and the two dipping faults in the step-over region, with very minor displacements occurring during the interseismic period when the northeast trending vertical faults are locked. These models suggest that the gently dippling central step-over fault is a reverse fault and that the steeper fault, extending to the southeast of the step-over, acts as a normal fault over the long term.
The discovery of long-term potentiation.
Lømo, Terje
2003-01-01
This paper describes circumstances around the discovery of long-term potentiation (LTP). In 1966, I had just begun independent work for the degree of Dr medicinae (PhD) in Per Andersen's laboratory in Oslo after an eighteen-month apprenticeship with him. Studying the effects of activating the perforant path to dentate granule cells in the hippocampus of anaesthetized rabbits, I observed that brief trains of stimuli resulted in increased efficiency of transmission at the perforant path-granule cell synapses that could last for hours. In 1968, Tim Bliss came to Per Andersen's laboratory to learn about the hippocampus and field potential recording for studies of possible memory mechanisms. The two of us then followed up my preliminary results from 1966 and did the experiments that resulted in a paper that is now properly considered to be the basic reference for the discovery of LTP. PMID:12740104
Stable long-term chronic brain mapping at the single-neuron level.
Fu, Tian-Ming; Hong, Guosong; Zhou, Tao; Schuhmann, Thomas G; Viveros, Robert D; Lieber, Charles M
2016-10-01
Stable in vivo mapping and modulation of the same neurons and brain circuits over extended periods is critical to both neuroscience and medicine. Current electrical implants offer single-neuron spatiotemporal resolution but are limited by such factors as relative shear motion and chronic immune responses during long-term recording. To overcome these limitations, we developed a chronic in vivo recording and stimulation platform based on flexible mesh electronics, and we demonstrated stable multiplexed local field potentials and single-unit recordings in mouse brains for at least 8 months without probe repositioning. Properties of acquired signals suggest robust tracking of the same neurons over this period. This recording and stimulation platform allowed us to evoke stable single-neuron responses to chronic electrical stimulation and to carry out longitudinal studies of brain aging in freely behaving mice. Such advantages could open up future studies in mapping and modulating changes associated with learning, aging and neurodegenerative diseases.
A high-frequency sonar for profiling small-scale subaqueous bedforms
Dingler, J.R.; Boylls, J.C.; Lowe, R.L.
1977-01-01
A high-resolution ultrasonic profiler has been developed which permits both laboratory and field studies of small-scale subaqueous bedforms. The device uses a 2.5-cm diameter piezoelectric ceramic crystal pulsed at a frequency of 4.5 MHz to obtain vertical accuracy and resolution of at least 1 mm. Compared to other small-scale profiling methods, this ultrasonic technique profiles the bottom more accurately and more rapidly without disturbing the bedforms. These characteristics are vital in wave-dominated nearshore zones where oscillatory flow and low visibility for the most part have stymied detailed bedform studies. In the laboratory the transducer is mounted directly to an instrument carriage. For field work the transducer housing is mounted in a 2 m long aluminum frame which is situated and operated by scuba divers. Observations using the device include ripple geometry and migration, the suspension height of sand during sheet flow, and long-term erosion/deposition at a point. ?? 1977.
Entanglement entropy in the long-range Kitaev chain
NASA Astrophysics Data System (ADS)
Ares, Filiberto; Esteve, José G.; Falceto, Fernando; de Queiroz, Amilcar R.
2018-06-01
In this paper we complete the study on the asymptotic behavior of the entanglement entropy for Kitaev chains with long-range pairing. We discover that when the couplings decay with the distance with a critical exponent new properties for the asymptotic growth of the entropy appear. The coefficient of the leading term is not universal any more and the connection with conformal field theories is lost. We perform a numerical and analytical approach to the problem showing a perfect agreement. In order to carry out the analytical study, a technique for computing the asymptotic behavior of block Toeplitz determinants with discontinuous symbols has been developed.
Use long short-term memory to enhance Internet of Things for combined sewer overflow monitoring
NASA Astrophysics Data System (ADS)
Zhang, Duo; Lindholm, Geir; Ratnaweera, Harsha
2018-01-01
Combined sewer overflow causes severe water pollution, urban flooding and reduced treatment plant efficiency. Understanding the behavior of CSO structures is vital for urban flooding prevention and overflow control. Neural networks have been extensively applied in water resource related fields. In this study, we collect data from an Internet of Things monitoring CSO structure and build different neural network models for simulating and predicting the water level of the CSO structure. Through a comparison of four different neural networks, namely multilayer perceptron (MLP), wavelet neural network (WNN), long short-term memory (LSTM) and gated recurrent unit (GRU), the LSTM and GRU present superior capabilities for multi-step-ahead time series prediction. Furthermore, GRU achieves prediction performances similar to LSTM with a quicker learning curve.
Know your community: Model applications in field research
USDA-ARS?s Scientific Manuscript database
The focus of this community is to promote the application of cropping or range system models in field research to help evaluate and develop optimum agricultural systems and management to achieve long-term economic and environmental sustainability under a changing climate. Model applications to a var...
The long-term post-outburst spin down and flux relaxation of magnetar swift J1822.3–1606
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scholz, P.; Kaspi, V. M.; Cumming, A., E-mail: pscholz@physics.mcgill.ca
2014-05-01
The magnetar Swift J1822.3–1606 entered an outburst phase in 2011 July. Previous X-ray studies of its post-outburst rotational evolution yielded inconsistent measurements of the spin-inferred magnetic field. Here we present the timing behavior and flux relaxation from over two years of Swift, RXTE, and Chandra observations following the outburst. We find that the ambiguity in previous timing solutions was due to enhanced spin down that resembles an exponential recovery following a glitch at the outburst onset. After fitting out the effects of the recovery, we measure a long-term spin-down rate of ν-dot =(−3.0 ± 0.3)×10{sup −16} s{sup –2} which impliesmore » a dipolar magnetic field of 1.35 × 10{sup 13} G, lower than all previous estimates for this source. We also consider the post-outburst flux evolution, and fit it with both empirical and crustal cooling models. We discuss the flux relaxation in the context of both crustal cooling and magnetospheric relaxation models.« less
Design and life-cycle considerations for unconventional-reservoir wells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miskimins, J.L.
2009-05-15
This paper provides an overview of design and life-cycle considerations for certain unconventional-reservoir wells. An overview of unconventional-reservoir definitions is provided. Well design and life-cycle considerations are addressed from three aspects: upfront reservoir development, initial well completion, and well-life and long-term considerations. Upfront-reservoir-development issues discussed include well spacing, well orientation, reservoir stress orientations, and tubular metallurgy. Initial-well-completion issues include maximum treatment pressures and rates, treatment diversion, treatment staging, flowback and cleanup, and dewatering needs. Well-life and long-term discussions include liquid loading, corrosion, refracturing and associated fracture reorientation, and the cost of abandonment. These design considerations are evaluated with case studiesmore » for five unconventional-reservoir types: shale gas (Barnett shale), tight gas (Jonah feld), tight oil (Bakken play), coalbed methane (CBM) (San Juan basin), and tight heavy oil (Lost Hills field). In evaluating the life cycle and design of unconventional-reservoir wells, 'one size' does not fit all and valuable knowledge and a shortening of the learning curve can be achieved for new developments by studying similar, more-mature fields.« less
Chiaia-Hernandez, Aurea C; Keller, Armin; Wächter, Daniel; Steinlin, Christine; Camenzuli, Louise; Hollender, Juliane; Krauss, Martin
2017-09-19
For polar and more degradable pesticides, not many data on long-term persistence in soil under field conditions and real application practices exist. To assess the persistence of pesticides in soil, a multiple-compound screening method (log K ow 1.7-5.5) was developed based on pressurized liquid extraction, QuEChERS and LC-HRMS. The method was applied to study 80 polar pesticides and >90 transformation products (TPs) in archived topsoil samples from the Swiss Soil Monitoring Network (NABO) from 1995 to 2008 with known pesticide application patterns. The results reveal large variations between crop type and field sites. For the majority of the sites 10-15 pesticides were identified with a detection rate of 45% at concentrations between 1 and 330 μg/kg dw in soil. Furthermore, TPs were detected in 47% of the cases where the "parent-compound" was applied. Overall, residues of about 80% of all applied pesticides could be detected with half of these found as TPs with a persistence of more than a decade.
Scleroderma in children: an update.
Zulian, Francesco; Cuffaro, Giorgio; Sperotto, Francesca
2013-09-01
Scleroderma, in its localized and systemic presentation, represents the third most frequent rheumatic condition in childhood after juvenile idiopathic arthritis and systemic lupus erythematosus. Early diagnosis, appropriate assessment and effective treatment are crucial to improve the long-term outcome. Recent studies, concerning histopathology and clinical associations with other conditions, open new horizons on the etiopathogenesis of scleroderma. New developments have been also reached in the field of outcome measures. In juvenile localized scleroderma (JLS), new techniques such as Doppler and laser Doppler imaging have shown their usefulness for the daily monitoring of the patients. In juvenile systemic sclerosis (JSSc), a new severity score has been developed and needs to be validated in future trials. Finally, a randomized, double-blind controlled trial, a multicenter consensus statement and long-term follow-up studies have confirmed the important role of methotrexate (MTX) for the treatment of JLS. Studies over recent years highlighted the role of imaging as outcome measures for JLS and introduced a severity score for JSSc. New studies on MTX confirmed its important role for the treatment of JLS.
De Rosis, Sabina; Nuti, Sabina
2018-01-01
eHealth is expected to contribute in tackling challenges for health care systems. However, it also imposes challenges. Financing strategies adopted at national as well regional levels widely affect eHealth long-term sustainability. In a public health care system, the public actor is among the main "buyers" eHealth. However, public interventions have been increasingly focused on cost containment. How to match these 2 aspects? This article explores some central issues, mainly related to financial aspects, in the development of effective and valuable eHealth strategies in a public health care system: How can the public health care system (as a "buyer") improve long-term success and sustainability of eHealth solutions? What levers are available to match in the long period different interests of different stakeholders in the eHealth field? A case study was performed in the Region of Tuscany, Italy. According to our results, win-win strategies should be followed. Investments should take into account the need to long-term finance solutions, for sustaining changes in health care organizations for obtaining benefits. To solve the interoperability issues, the concept of the "platform approach" emerged, based on collaboration within and between organizations. Private sector as well as beneficiaries and final users of the eHealth solutions should participate in their design, provision, and monitoring. For creating value for all, the evidence gap and the financial needs could be addressed with a pull mechanism of funding, aimed at paying according to the outcomes produced by the eHealth solution, on the base of an ongoing monitoring, measurement, and evaluation of the outcomes. © 2017 The Authors. The International Journal of Health Planning and Management published by John Wiley & Sons Ltd.
Epidemiologic evidence on mobile phones and tumor risk: a review.
Ahlbom, Anders; Feychting, Maria; Green, Adele; Kheifets, Leeka; Savitz, David A; Swerdlow, Anthony J
2009-09-01
This review summarizes and interprets epidemiologic evidence bearing on a possible causal relation between radiofrequency field exposure from mobile phone use and tumor risk. In the last few years, epidemiologic evidence on mobile phone use and the risk of brain and other tumors of the head in adults has grown in volume, geographic diversity of study settings, and the amount of data on longer-term users. However, some key methodologic problems remain, particularly with regard to selective nonresponse and inaccuracy and bias in recall of phone use. Most studies of glioma show small increased or decreased risks among users, although a subset of studies show appreciably elevated risks. We considered methodologic features that might explain the deviant results, but found no clear explanation. Overall the studies published to date do not demonstrate an increased risk within approximately 10 years of use for any tumor of the brain or any other head tumor. Despite the methodologic shortcomings and the limited data on long latency and long-term use, the available data do not suggest a causal association between mobile phone use and fast-growing tumors such as malignant glioma in adults (at least for tumors with short induction periods). For slow-growing tumors such as meningioma and acoustic neuroma, as well as for glioma among long-term users, the absence of association reported thus far is less conclusive because the observation period has been too short.
Effect of long-term drought on carbon allocation and nitrogen uptake of Pinus sylvestris seedlings
NASA Astrophysics Data System (ADS)
Pumpanen, Jukka; Aaltonen, Heidi; Lindén, Aki; Köster, Kajar; Biasi, Christina; Heinonsalo, Jussi
2015-04-01
Weather extremes such as drought events are expected to increase in the future as a result of climate change. The drought affects the allocation of carbon assimilated by plants e.g. by modifying the root to shoot ratio, amount of fine roots and the amount of mycorrhizal fungal hyphae. We studied the effect of long term drought on the allocation of carbon in a common garden experiment with 4-year-old Pinus sylvestris seedlings. Half of the seedlings were exposed to long-term drought by setting the soil water content close to wilting point for over two growing seasons whereas the other half was grown in soil close to field capacity. We conducted a pulse labelling with 13CO2 in the end of the study by injecting a known amount of 13C enriched CO2 to the seedlings and measuring the CO2 uptake and distribution of 13C to the biomass of the seedlings and to the root and rhizosphere respiration. In addition, we studied the effect of drought on the decomposition of needle litter and uptake of nitrogen by 15N labelled needles buried in the soil in litter bags. The litterbags were collected and harvested in the end of the experiment and the changes in microbial community in the litterbags were studied from the phospholipid fatty acid (PLFA) composition. We also determined the 15N isotope concentrations from the needles of the seedlings to study the effect of drought on the nitrogen uptake of the seedlings. Our results indicate that the drought had a significant effect both on the biomass allocation of the seedlings and on the microbial species composition. The amount of carbon allocated belowground was much higher in the seedlings exposed to drought compared to the control seedlings. The seedlings seemed to adapt their carbon allocation to long-term drought to sustain adequate needle biomass and water uptake. The seedlings also adapted their osmotic potential and photosynthesis capacity to sustain the long-term drought as was indicated by the measurements of osmotic potential and photosynthetic light response.
Grassi, S; Malfagia, C; Pettorossi, V E
1998-11-01
In rat brainstem slices, we investigated the possible role of metabotropic glutamate receptors in modulating the synaptic transmission within the medial vestibular nuclei, under basal and plasticity inducing conditions. We analysed the effect of the metabotropic glutamate receptor antagonist (R,S)-alpha-methyl-4-carboxyphenylglycine on the amplitude of the field potentials and latency of unitary potentials evoked in the ventral portion of the medial vestibular nuclei by primary vestibular afferent stimulation, and on the induction and maintenance of long-term potentiation, after high-frequency stimulation. Two effects were observed, consisting of a slight increase of the field potentials and reduction of unit latency during the drug infusion, and a further long-lasting development of these modifications after the drug wash-out. The long-term effect depended on N-methyl-D-aspartate receptor activation, as D,L-2-amino-5-phosphonopentanoic acid prevented its development. We suggest that (R,S)-alpha-methyl-4carboxyphenylglycine enhances the vestibular responses and induces N-methyl-D-aspartate-dependent long-term potentiation by increasing glutamate release, through the block of presynaptic metabotropic glutamate receptors which actively inhibit it. The block of these receptors was indirectly supported by the fact that the agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid reduced the vestibular responses and blocked the induction of long-term potentiation by high-frequency stimulation. The simultaneous block of metabotropic glutamate receptors facilitating synaptic plasticity, impedes the full expression of the long-term effect throughout the (R,S)-alpha-methyl-4-carboxyphenylglycine infusion. The involvement of such a facilitatory mechanism in the potentiation is supported by its reversible reduction following a second (R,S)-alpha-methyl-4-carboxyphenylglycine infusion. The drug also reduced the expression of potentiation induced by high-frequency stimulation. Conversely the electrical long-term potentiation was still induced, but it was occluded by the previous drug potentiation. We conclude that metabotropic glutamate receptors play a dual functional role in the medial vestibular nuclei, consisting in the inhibition of glutamate release under basal conditions, and the facilitation of N-methyl-D-aspartate-dependent plasticity phenomena.
Measurement and analysis of electromagnetic fields from trams, trains and hybrid cars.
Halgamuge, Malka N; Abeyrathne, Chathurika D; Mendis, Priyan
2010-10-01
Electricity is used substantially and sources of electric and magnetic fields are, unavoidably, everywhere. The transportation system is a source of these fields, to which a large proportion of the population is exposed. Hence, investigation of the effects of long-term exposure of the general public to low-frequency electromagnetic fields caused by the transportation system is critically important. In this study, measurements of electric and magnetic fields emitted from Australian trams, trains and hybrid cars were investigated. These measurements were carried out under different conditions, locations, and are summarised in this article. A few of the measured electric and magnetic field strengths were significantly lower than those found in prior studies. These results seem to be compatible with the evidence of the laboratory studies on the biological effects that are found in the literature, although they are far lower than international levels, such as those set up in the International Commission on Non-Ionising Radiation Protection guidelines.
Public magnetic field exposure based on internal current density for electric low voltage systems.
Keikko, Tommi; Seesvuori, Reino; Hyvönen, Martti; Valkealahti, Seppo
2009-04-01
A measurement concept utilizing a new magnetic field exposure metering system has been developed for indoor substations where voltage is transformed from a medium voltage of 10 or 20 kV to a low voltage of 400 V. The new metering system follows the guidelines published by the International Commission on Non-Ionizing Radiation Protection. It can be used to measure magnetic field values, total harmonic distortion of the magnetic field, magnetic field exposure ratios for public and workers, load current values, and total harmonic distortion of the load current. This paper demonstrates how exposure to non-sinusoidal magnetic fields and magnetic flux density exposure values can be compared directly with limit values for internal current densities in a human body. Further, we present how the magnetic field and magnetic field exposure behaves in the vicinity of magnetic field sources within the indoor substation and in the neighborhood. Measured magnetic fields around the substation components have been used to develop a measurement concept by which long-term measurements in the substations were performed. Long-term measurements revealed interesting and partly unexpected dependencies between the measured quantities, which have been further analyzed. The principle of this paper is to substitute a demanding exposure measurement with measurements of the basic quantities like the 50 Hz fundamental magnetic field component, which can be estimated based on the load currents for certain classes of substation lay-out.
Effects of treadmill exercise intensity on spatial working memory and long-term memory in rats.
Wang, Xiao-Qin; Wang, Gong-Wu
2016-03-15
Moderate exercise promotes learning and memory. Most studies mainly focused on memory exercise effects of in the ageing and patients. There is lack of quantitative research about effect of regular exercise intensity on different memory types in normal subjects. Present study investigated the effects of different intensities of treadmill exercise on working memory and long-term memory. Fifty female Wistar rats were trained by T-maze delayed spatial alternation (DSA) task with 3 delays (10s, 60s and 300s). Then they got a 30min treadmill exercise for 30days in 4 intensities (control, 0m/min; lower, 15m/min; middle, 20m/min, and higher, 30m/min). Then animals were tested in DSA, passive avoidance and Morris water maze tasks. 1. Exercise increased the neuronal density of hippocampal subregions (CA1, CA3 and dentate gyrus) vs. naïve/control. 2. In DSA task, all groups have similar baseline, lower intensity improved 10s delay accuracy vs. baseline/control; middle and higher intensities improved 300s delay accuracy vs. baseline/control. 3. In water maze learning, all groups successfully found the platform, but middle intensity improved platform field crossing times vs. control in test phase. Present results suggested that treadmill exercise can improve long-term spatial memory and working memory; lower intensity benefits to short-term delayed working memory, and middle or higher intensity benefits to long-term delayed working memory. There was an inverted U dose-effect relationship between exercise intensity and memory performance, but exercise -working memory effect was impacted by delay duration. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Huang, Zhang-Ting; Li, Yong-Fu; Jiang, Pei-Kun; Chang, Scott X.; Song, Zhao-Liang; Liu, Juan; Zhou, Guo-Mo
2014-01-01
Carbon (C) occluded in phytolith (PhytOC) is highly stable at millennium scale and its accumulation in soils can help increase long-term C sequestration. Here, we report that soil PhytOC storage significantly increased with increasing duration under intensive management (mulching and fertilization) in Lei bamboo (Phyllostachys praecox) plantations. The PhytOC storage in 0-40 cm soil layer in bamboo plantations increased by 217 Mg C ha-1, 20 years after being converted from paddy fields. The PhytOC accumulated at 79 kg C ha-1 yr-1, a rate far exceeding the global mean long-term soil C accumulation rate of 24 kg C ha-1 yr-1 reported in the literature. Approximately 86% of the increased PhytOC came from the large amount of mulch applied. Our data clearly demonstrate the decadal scale management effect on PhytOC accumulation, suggesting that heavy mulching is a potential method for increasing long-term organic C storage in soils for mitigating global climate change.
USDA-ARS?s Scientific Manuscript database
A fall-planted cover crop is a management practice with multiple benefits including reducing nitrate losses from artificially drained fields. We used the Root Zone Water Quality Model (RZWQM) to simulate the impact of a cereal rye cover crop on reducing nitrate losses from drained fields across five...
Biological Response to the Dynamic Spectral-Polarized Underwater Light Field
2011-09-30
www.bio.utexas.edu/research/cummingslab/ LONG-TERM GOALS Camouflage in marine environments requires matching all of the background optical ...polarized light field in near-shore and near-surface environments (2) Characterize the biological camouflage response of organisms to these dynamic optical ...field will be measured by the simultaneous deployment of a comprehensive optical suite including underwater video-polarimetry (Cummings), inherent
Rodney C. De Groot; Douglas M. Crawford; Jack Norton; John Keith
2000-01-01
The durability of preservative-treated stakes of second-growth Coastal Douglas-fir was evaluated in a field plot in northern Queensland, Australia. Results from this field trial indicate that second-growth Douglas-fir can be treated with preservatives to meet Australian standards and will provide long-term durability in adverse environments. Data presented indicate...
The Origins of the Field Concept in Physics
NASA Astrophysics Data System (ADS)
McMullin, Ernan
The term, ``field,'' made its first appearance in physics as a technical term in the mid-nineteenth century. But the notion of what later came to be called a field had been a long time in gestation. Early discussions of magnetism and of the cause of the ocean tides had long ago suggested the idea of a ``zone of influence'' surrounding certain bodies. Johannes Kepler's mathematical rendering of the orbital motion of Mars encouraged him to formulate what he called ``a true theory of gravity'' involving the notion of attraction. Isaac Newton went on to construct an eminently effective dynamics, with attraction as its primary example of force. Was his a field theory? Historians of science disagree. Much depends on whether a theory consistent with the notion of action at a distance ought qualify as a ``field'' theory. Roger Boscovich and Immanuel Kant later took the Newtonian concept of attraction in new directions. It was left to Michael Faraday to propose the ``physical existence'' of lines of force and to James Clerk Maxwell to add as criterion the presence of energy as the ontological basis for a full-blown ``field theory'' of electromagnetic phenomena.
Dittmar, Jessica; Voegelin, Andreas; Maurer, Felix; Roberts, Linda C; Hug, Stephan J; Saha, Ganesh C; Ali, M Ashraf; Badruzzaman, A Borhan M; Kretzschmar, Ruben
2010-12-01
Groundwater rich in arsenic (As) is extensively used for dry season boro rice cultivation in Bangladesh, leading to long-term As accumulation in soils. This may result in increasing levels of As in rice straw and grain, and eventually, in decreasing rice yields due to As phytotoxicity. In this study, we investigated the As contents of rice straw and grain over three consecutive harvest seasons (2005-2007) in a paddy field in Munshiganj, Bangladesh, which exhibits a documented gradient in soil As caused by annual irrigation with As-rich groundwater since the early 1990s. The field data revealed that straw and grain As concentrations were elevated in the field and highest near the irrigation water inlet, where As concentrations in both soil and irrigation water were highest. Additionally, a pot experiment with soils and rice seeds from the field site was carried out in which soil and irrigation water As were varied in a full factorial design. The results suggested that both soil As accumulated in previous years and As freshly introduced with irrigation water influence As uptake during rice growth. At similar soil As contents, plants grown in pots exhibited similar grain and straw As contents as plants grown in the field. This suggested that the results from pot experiments performed at higher soil As levels can be used to assess the effect of continuing soil As accumulation on As content and yield of rice. On the basis of a recently published scenario of long-term As accumulation at the study site, we estimate that, under unchanged irrigation practice, average grain As concentrations will increase from currently ∼0.15 mg As kg(-1) to 0.25-0.58 mg As kg(-1) by the year 2050. This translates to a 1.5-3.8 times higher As intake by the local population via rice, possibly exceeding the provisional tolerable As intake value defined by FAO/WHO.
NASA Astrophysics Data System (ADS)
Kniffka, Anke; Benedetti, Angela; Knippertz, Peter; Stanelle, Tanja; Brooks, Malcolm; Deetz, Konrad; Maranan, Marlon; Rosenberg, Philip; Pante, Gregor; Allan, Richard; Hill, Peter; Adler, Bianca; Fink, Andreas; Kalthoff, Norbert; Chiu, Christine; Vogel, Bernhard; Field, Paul; Marsham, John
2017-04-01
DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa) is an EU-funded project that aims to determine the influence of anthropogenic and natural emissions on the atmospheric composition, air quality, weather and climate over southern West Africa. DACCIWA organised a major international field campaign in June-July 2016 and involves a wide range of modelling activities. Here we report about the coordinated model evaluation performed in the framework of DACCIWA focusing on meteorological fields. This activity consists of two elements: (a) the quality of numerical weather prediction during the field campaign, (b) the ability of seasonal and climate models to represent the mean state and its variability. For the first element, the extensive observations from the main field campaign in West Africa in June-July 2016 (ground supersites, radiosondes, aircraft measurements) will be combined with conventional data (synoptic stations, satellites data from various sensors) to evaluate models against. The forecasts include operational products from centres such as the ECMWF, UK MetOffice and the German Weather Service and runs specifically conducted for the planning and the post-analysis of the field campaign using higher resolutions (e.g., WRF, COSMO). The forecast and the observations are analysed in a concerted way to assess the ability of the models to represent the southern West African weather systems and secondly to provide a comprehensive synoptic overview of the state of the atmosphere. In a second step the process will be extended to long-term modelling periods. This includes both seasonal and climate models, respectively. In this case, the observational dataset contains long-term satellite observations and station data, some of which were digitised from written records in the framework of DACCIWA. Parameter choice and spatial averaging will build directly on the weather forecasting evaluation to allow an assessment of the impact of short-term errors on long-term simulations.
Losiak, Anna; Gołębiowska, Izabela; Orgel, Csilla; Moser, Linda; MacArthur, Jane; Boyd, Andrea; Hettrich, Sebastian; Jones, Natalie; Groemer, Gernot
2014-05-01
MARS2013 was an integrated Mars analog field simulation in eastern Morocco performed by the Austrian Space Forum between February 1 and 28, 2013. The purpose of this paper is to discuss the system of data processing and utilization adopted by the Remote Science Support (RSS) team during this mission. The RSS team procedures were designed to optimize operational efficiency of the Flightplan, field crew, and RSS teams during a long-term analog mission with an introduced 10 min time delay in communication between "Mars" and Earth. The RSS workflow was centered on a single-file, easy-to-use, spatially referenced database that included all the basic information about the conditions at the site of study, as well as all previous and planned activities. This database was prepared in Google Earth software. The lessons learned from MARS2013 RSS team operations are as follows: (1) using a spatially referenced database is an efficient way of data processing and data utilization in a long-term analog mission with a large amount of data to be handled, (2) mission planning based on iterations can be efficiently supported by preparing suitability maps, (3) the process of designing cartographical products should start early in the planning stages of a mission and involve representatives of all teams, (4) all team members should be trained in usage of cartographical products, (5) technical problems (e.g., usage of a geological map while wearing a space suit) should be taken into account when planning a work flow for geological exploration, (6) a system that helps the astronauts to efficiently orient themselves in the field should be designed as part of future analog studies.
NASA Astrophysics Data System (ADS)
Schwab, M. P.; Klaus, J.; Pfister, L.; Weiler, M.
2016-12-01
Over the past decades, stream sampling protocols for hydro-geochemical parameters were often limited by logistical and technological constraints. While long-term monitoring protocols were typically based on weekly sampling intervals, high frequency sampling was commonly limited to a few single events. In this contribution, we combined high frequency and long-term measurements to understand DOC and nitrate dynamics in a forest headwater for different runoff events and seasons. Our study area is the forested Weierbach catchment (0.47 km2) in Luxembourg, where the fractured schist bedrock is covered by cambisol soils. The runoff response is characterized by a double peak behaviour. The first peak occurs during or right after a rainfall event triggered by fast near surface runoff generation processes, while a second delayed peak lasts several days and is generated by subsurface flow. This second peak occurs only if a distinct storage threshold of the catchment is exceeded. Our observations were carried out with a field deployable UV-Vis spectrometer measuring DOC and nitrate concentrations in-situ at 15 min intervals for more than two years. In addition, a long-term validation was carried out with data obtained from the analysis of water collected with grab samples. The long-term, high-frequency measurements allowed us to calculate a complete and detailed balance of DOC and nitrate export over two years. Transport behaviour of the DOC and nitrate showed different dynamics between the first and second hydrograph peaks. DOC is mainly exported during the first peaks, while nitrate is mostly exported during the delayed second peaks. Biweekly end-member measurement of soil and groundwater over several years enables us to link the behaviour of DOC and nitrate export to various end-members in the catchment. Altogether, the long-term and high-frequency time series provides the opportunity to study DOC and nitrate export processes without having to just rely only on either a few single event measurements or coarse measurement protocols.
Traumatisation and Long-Term Stress Cascades: Case Report--Jan M.
ERIC Educational Resources Information Center
Herz, Birgit
2011-01-01
Numerous services in the field of social, emotional and behavioural difficulties (SEBD) are active, with different qualities and outcomes in their work. Different professions are also involved in this field between regular and special schools, the children and young people welfare system, the psychiatric ward, the police, therapeutically services…
Citrus Huanglongbing tolerance in Australian Citrus Relatives, Microcitrus and Eremocirus
USDA-ARS?s Scientific Manuscript database
Tolerance, or resistance to citrus huanglongbing will be important as a long term solution for this disease. In a field trial conducted with over 1000 plants belonging to different genera in the sub-family Aurantioideae, we observed field tolerance in many Australian citrus relatives. To confirm the...
We present the results of long term (500 days) measurements of the bulk conductivity in a field and laboratory experiment. Our objective was to determine the rate of change in bulk conductivity and whether this rate of change correlated with the petroleum hydrocarbon degradation...
NASA Astrophysics Data System (ADS)
Zhao, T.; Wang, J.; Dai, A.
2015-12-01
Many multi-decadal atmospheric reanalysis products are avialable now, but their consistencies and reliability are far from perfect. In this study, atmospheric precipitable water (PW) from the NCEP/NCAR, NCEP/DOE, MERRA, JRA-55, JRA-25, ERA-Interim, ERA-40, CFSR and 20CR reanalyses is evaluated against homogenized radiosonde observations over China during 1979-2012 (1979-2001 for ERA-40). Results suggest that the PW biases in the reanalyses are within ˜20% for most of northern and eastern China, but the reanalyses underestimate the observed PW by 20%-40% over western China, and by ˜60% over the southwestern Tibetan Plateau. The newer-generation reanalyses (e.g., JRA25, JRA55, CFSR and ERA-Interim) have smaller root-mean-square error (RMSE) than the older-generation ones (NCEP/NCAR, NCEP/DOE and ERA-40). Most of the reanalyses reproduce well the observed PW climatology and interannual variations over China. However, few reanalyses capture the observed long-term PW changes, primarily because they show spurious wet biases before about 2002. This deficiency results mainly from the discontinuities contained in reanalysis RH fields in the mid-lower troposphere due to the wet bias in older radiosonde records that are assimilated into the reanalyses. An empirical orthogonal function (EOF) analysis revealed two leading modes that represent the long-term PW changes and ENSO-related interannual variations with robust spatial patterns. The reanalysis products, especially the MERRA and JRA-25, roughly capture these EOF modes, which account for over 50% of the total variance. The results show that even during the post-1979 satellite era, discontinuities in radiosonde data can still induce large spurious long-term changes in reanalysis PW and other related fields. Thus, more efforts are needed to remove spurious changes in input data for future long-term reanlayses.
WAYNE J. ARENDT
2005-01-01
I calculated various shell properties, water vapor loss, and hatching success of eggs of the Pearly-eyed Thrasher (Margarops fuscatus) using measurements obtained during a long-term study in the Luquillo Mountains, Puerto Rico. Empirical results were comparable to standard reference formulae, demonstrating that published formulae can be used with confidence by field...
Douglas McCreary; Laurence R. Costello; Jerry Tecklin; Katherine Jones; David Labadie
2002-01-01
Treeshelters are individual seedling protectors that can accelerate height growth of native California oaks. There is concern, however, that this growth may occur at the expense of the roots, resulting in poor long-term field performance. This study could detect no differences between protected and unprotected seedlings in shoot weight, root weight or shoot/root ratios...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Van Lonkhuyzen, R.A.
1999-12-15
The US Department of Energy proposes to construct a groundwater interceptor trench near the Weldon Spring Quarry at the Weldon Spring Site in Missouri. The trench would be located near two palustrine wetland areas. Impacts to wetland hydrology and biotic communities are expected to be negligible. No long-term adverse impacts to floodplains are expected.
Modeling the sustainability of a ceramic water filter intervention.
Mellor, Jonathan; Abebe, Lydia; Ehdaie, Beeta; Dillingham, Rebecca; Smith, James
2014-02-01
Ceramic water filters (CWFs) are a point-of-use water treatment technology that has shown promise in preventing early childhood diarrhea (ECD) in resource-limited settings. Despite this promise, some researchers have questioned their ability to reduce ECD incidences over the long term since most effectiveness trials conducted to date are less than one year in duration limiting their ability to assess long-term sustainability factors. Most trials also suffer from lack of blinding making them potentially biased. This study uses an agent-based model (ABM) to explore factors related to the long-term sustainability of CWFs in preventing ECD and was based on a three year longitudinal field study. Factors such as filter user compliance, microbial removal effectiveness, filter cleaning and compliance declines were explored. Modeled results indicate that broadly defined human behaviors like compliance and declining microbial effectiveness due to improper maintenance are primary drivers of the outcome metrics of household drinking water quality and ECD rates. The model predicts that a ceramic filter intervention can reduce ECD incidence amongst under two year old children by 41.3%. However, after three years, the average filter is almost entirely ineffective at reducing ECD incidence due to declining filter microbial removal effectiveness resulting from improper maintenance. The model predicts very low ECD rates are possible if compliance rates are 80-90%, filter log reduction efficiency is 3 or greater and there are minimal long-term compliance declines. Cleaning filters at least once every 4 months makes it more likely to achieve very low ECD rates as does the availability of replacement filters for purchase. These results help to understand the heterogeneity seen in previous intervention-control trials and reemphasize the need for researchers to accurately measure confounding variables and ensure that field trials are at least 2-3 years in duration. In summary, the CWF can be a highly effective tool in the fight against ECD, but every effort should be made by implementing agencies to ensure consistent use and maintenance. Copyright © 2013 Elsevier Ltd. All rights reserved.
Radiofrequency exposure in the Neonatal Medium Care Unit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Calvente, I.
The aims of this study were to characterize electromagnetic fields of radiofrequency (RF-EMF) levels generated in a Neonatal Medium Care Unit and to analyze RF-EMF levels inside unit’s incubators. Spot and long-term measurements were made with a dosimeter. The spot measurement mean was 1.51±0.48 V/m. Higher values were found in the proximity to the window and to the incubator evaluated. Mean field strength for the entire period of 17 h was 0.81 (±0.07) V/m and the maximum value was 1.58 V/m for long-term RF-EMF measurements in the incubator. Values found during the night period were higher than those found duringmore » the day period. It is important to consider RF-EMF exposure levels in neonatal care units, due to some evidence of adverse health effects found in children and adults. Characterization of RF-EMF exposure may be important to further investigate the mechanisms and underlying effects of electromagnetic fields (EMF) on infant health. A prudent avoidance strategy should be adopted because newborns are at a vulnerable stage of development and the actual impact of EMF on premature infants is unknown. - Highlights: • The increasing use of RF-EMF suggests an urgent need for more research in this field. • Health consequences of RF-EMF exposure on infants are not well known. • Description of RF-EMF exposure is vital in further study mechanisms on infant health. • Considering newborns vulnerability, it is wise to adopt a prudent avoidance strategy.« less
Ghaderi, Sara; Engeland, Anders; Gunnes, Maria Winther; Moster, Dag; Ruud, Ellen; Syse, Astri; Wesenberg, Finn; Bjørge, Tone
2016-02-01
The number of young cancer survivors has increased over the past few decades due to improvement in treatment regimens, and understanding of long-term effects among the survivors has become even more important. Educational achievements and choice of educational fields were explored here. Five-year cancer survivors born in Norway during 1965-1985 (diagnosed <19 years) were included in our analysis by linking Norwegian population-based registries. Cox regression was applied to study the educational attainment among survivors of central nervous system (CNS) tumours, those assumed to have received CNS-directed therapy, and other cancer survivors relative to the cancer-free population. Logistic regression was used to compare the choice of educational fields between the cancer survivors at undergraduate and graduate level and the cancer-free population. Overall, a lower proportion of the cancer survivors completed intermediate (67 vs. 70 %), undergraduate (31 vs. 35 %) and graduate education (7 vs. 9 %) compared with the cancer-free population. Deficits in completion of an educational level were mainly observed among survivors of CNS-tumours and those assumed to have received CNS-directed therapy. Choices of educational fields among cancer survivors were in general similar with the cancer-free population at both undergraduate and graduate levels. Survivors of CNS-tumours and those assumed to have received CNS-directed therapy were at increased risk for educational impairments compared with the cancer-free population. Choices of educational fields were in general similar. Careful follow-up of the survivors of CNS-tumours and those assumed to have received CNS-directed therapy is important at each level of education.
Zhang, Li; Zhang, Li; Wu, Dong-Xia; Zhang, Jun-Jun
2014-06-01
In order to clarify the effects of tillage patterns on farmland weed community structure and crop production characteristics, based on 10 years location experiment with no-tillage, subsoiling and conventional tillage in the cold and arid region of North China, and supplementary experiment of plowing after 10 years no-tillage and subsoiling, oat was planted in 2 soils under different tillage patterns, and field weed total density, dominant weed types, weed diversity index, field weed biomass and oats yield were measured. The results showed that the regional weed community was dominated by foxtail weed (Setaira viridis); the weed density under long-term no-tillage was 2.20-5.14 times of tillage at different growing stages of oat, but there were no significant differences between conditional tillage and plowing after long-term no-tillage and subsoiling. Field weed Shannon diversity indices were 0.429 and 0.531, respectively, for sandy chestnut soil and loamy meadow soil under no-tillage conditions, and field weed biomass values were 1.35 and 2.26 times of plowing treatment, while the oat biomass values were only 2807.4 kg x hm(-2) and 4053.9 kg x hm(-2), decreased by 22.3% and 46.2%, respectively. The results showed that the weed community characteristics were affected by both tillage patterns and soil types. Long-term no-tillage farmland in the cold and arid region of North China could promote the natural evolution of plant communities by keeping more perennial weeds, and the plowing pattern lowered the annual weed density, eliminated perennial weeds with shallow roots, and stimulated perennial weeds with deep roots.
Maddox, Stephanie A.; Watts, Casey S.; Schafe, Glenn E.
2014-01-01
We have previously shown that auditory Pavlovian fear conditioning is associated with an increase in DNA methyltransferase (DNMT) expression in the lateral amygdala (LA) and that intra-LA infusion or bath application of an inhibitor of DNMT activity impairs the consolidation of an auditory fear memory and long-term potentiation (LTP) at thalamic and cortical inputs to the LA, in vitro. In the present study, we use awake behaving neurophysiological techniques to examine the role of DNMT activity in memory-related neurophysiological changes accompanying fear memory consolidation and reconsolidation in the LA, in vivo. We show that auditory fear conditioning results in a training-related enhancement in the amplitude of short-latency auditory-evoked field potentials (AEFPs) in the LA. Intra-LA infusion of a DNMT inhibitor impairs both fear memory consolidation and, in parallel, the consolidation of training-related neural plasticity in the LA; that is, short-term memory (STM) and short-term training-related increases in AEFP amplitude in the LA are intact, while long-term memory (LTM) and long-term retention of training-related increases in AEFP amplitudes are impaired. In separate experiments, we show that intra-LA infusion of a DNMT inhibitor following retrieval of an auditory fear memory has no effect on post-retrieval STM or short-term retention of training-related changes in AEFP amplitude in the LA, but significantly impairs both post-retrieval LTM and long-term retention of AEFP amplitude changes in the LA. These findings are the first to demonstrate the necessity of DNMT activity in the consolidation and reconsolidation of memory-associated neural plasticity, in vivo. PMID:24291571
NASA Astrophysics Data System (ADS)
Koal, Philipp; Schilling, Rolf; Gerl, Georg; Pritsch, Karin; Munch, Jean Charles
2015-04-01
In order to achieve a reduction of greenhouse gas emissions, modern agronomic management practices need to be established. Therefore, to assess the effect of different farming practices on greenhouse gas emissions, reliable data are required. The experiment covers and compares two main aspects of agricultural management for a better implementation of sustainable land use. The focus lies on the determination and interpretation of greenhouse gas emissions, however, regarding in each case a different agricultural management system, namely an organic farming system and an integrated farming system where the effect of diverse tillage systems and fertilisation practices are observed. In addition, with analysis of the alterable biological, physical and chemical soil properties a link between the impact of different management systems on greenhouse gas emissions and the observed cycle of matter in the soil, especially the nitrogen and carbon cycle, will be enabled. Measurements have been carried out on long-term field trials at the Research Farm Scheyern located in a Tertiary hilly landscape approximately 40 km north of Munich (South Germany). The long-term field trials of the organic and integrated farming system were started in 1992. Since then parcels of land (each around 0.2-0.4 ha) with a particular interior plot set-up have been conducted with the same crop rotation, tillage and fertilisation practice referring to organic and integrated farming management. Thus, the management impacts on the soil of more than 20 years are being examined. Fluxes of CH4, N2O and CO2 have been monitored since 2007 for the integrated farming system trial and since 2012 for the organic farming system trial using an automated system which consists of chambers (0.4 m2 area) with a motor-driven lid, an automated gas sampling unit, an on-line gas chromatographic analysis system, and a control and data logging unit. Precipitation and temperature data have been observed for each experimental field to include weather effects. The main outcomes are the analysis of temporal and spatial dynamics of greenhouse gas emissions influenced by management practice events (i.a. fertilisation, crop incorporation and tillage) and weather effects (drying-rewetting, freezing-thawing, intense rainfall and dry periods) and the creation of impact studies comparing the farming systems (organic vs integrated) and the management practices (minimum tillage vs conventional tillage; high vs low fertilisation). Physical, chemical and biological soil properties (i.a. texture, mineral nitrogen, soil organic carbon and microbial biomass) have been examined in short time intervals to aggregate the parameters and processes influencing the greenhouse gas emissions and to build a linkage between soil organic matter and greenhouse gas emissions. Moreover, with the comparison of the investigated similar long-term field experiments and the collected agronomic data (harvest, tillage and fertilisation practices) the study could contribute to a contemporary set of "best management practices" and could provide a help to create decision tools for stakeholders such as farmers.
The effects of long-term dopaminergic treatment on locomotor behavior in rats.
Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco
2014-12-01
Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole-PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions.
The effects of long-term dopaminergic treatment on locomotor behavior in rats
Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco
2014-01-01
Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole—PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions. PMID:26483930
Interventions on Bullying and Cyberbullying in Schools: A Systematic Review
Cantone, Elisa; Piras, Anna P; Vellante, Marcello; Preti, Antonello; Daníelsdóttir, Sigrun; D’Aloja, Ernesto; Lesinskiene, Sigita; Angermeyer, Mathhias C; Carta, Mauro G; Bhugra, Dinesh
2015-01-01
Background : bullying (and cyberbullying) is a widespread phenomenon among young people and it is used to describe interpersonal relationships characterized by an imbalance of power. In this relationships often show aggressive behavior and intentional "harm doing" repeated over time. The prevalence of bullying among youth has been reported to vary widely among countries (5.1%-41.4%) and this behavior seems generally higher among student boys than girls. Several school interventions have been developed to reduce bullying, but reported inconsistent results possibly related to limitations in the study design or to other methodological shortcomings. Aims : evaluating randomized-controlled trials (RTCs) conducted between 2000 and 2013 to assess the effectiveness of school interventions on bullying and cyberbullying. Methods : a systematic search of the scientific literature was conducted on Pubmed/Medline and Ebsco online databases. We also contacted experts in the field of preventive bullying research. Results : 17 studies met the inclusion criteria. The majority of studies did not show positive effects in the long term; the interventions focused on the whole school were more effective in reducing bullying than interventions delivered through classroom curricula or social skills training alone. Conclusion : while there is evidence that programs aimed at reducing bullying can be effective in the short term, their long-term effectiveness has not been established, and there are important differences in the results based on gender, age and socio-economic status of participants. Internal inconsistency in the findings of some studies, together with the wide variability of experimental designs and lack of common standardized measures in outcome evaluation, are important limitations in this field of research. PMID:25834628
Interventions on bullying and cyberbullying in schools: a systematic review.
Cantone, Elisa; Piras, Anna P; Vellante, Marcello; Preti, Antonello; Daníelsdóttir, Sigrun; D'Aloja, Ernesto; Lesinskiene, Sigita; Angermeyer, Mathhias C; Carta, Mauro G; Bhugra, Dinesh
2015-01-01
Background : bullying (and cyberbullying) is a widespread phenomenon among young people and it is used to describe interpersonal relationships characterized by an imbalance of power. In this relationships often show aggressive behavior and intentional "harm doing" repeated over time. The prevalence of bullying among youth has been reported to vary widely among countries (5.1%-41.4%) and this behavior seems generally higher among student boys than girls. Several school interventions have been developed to reduce bullying, but reported inconsistent results possibly related to limitations in the study design or to other methodological shortcomings. Aims : evaluating randomized-controlled trials (RTCs) conducted between 2000 and 2013 to assess the effectiveness of school interventions on bullying and cyberbullying. Methods : a systematic search of the scientific literature was conducted on Pubmed/Medline and Ebsco online databases. We also contacted experts in the field of preventive bullying research. Results : 17 studies met the inclusion criteria. The majority of studies did not show positive effects in the long term; the interventions focused on the whole school were more effective in reducing bullying than interventions delivered through classroom curricula or social skills training alone. Conclusion : while there is evidence that programs aimed at reducing bullying can be effective in the short term, their long-term effectiveness has not been established, and there are important differences in the results based on gender, age and socio-economic status of participants. Internal inconsistency in the findings of some studies, together with the wide variability of experimental designs and lack of common standardized measures in outcome evaluation, are important limitations in this field of research.
Ellison, C. L.; Burby, J. W.; Qin, H.
2015-11-01
One popular technique for the numerical time advance of charged particles interacting with electric and magnetic fields according to the Lorentz force law [1], [2], [3] and [4] is the Boris algorithm. Its popularity stems from simple implementation, rapid iteration, and excellent long-term numerical fidelity [1] and [5]. Excellent long-term behavior strongly suggests the numerical dynamics exhibit conservation laws analogous to those governing the continuous Lorentz force system [6]. Moreover, without conserved quantities to constrain the numerical dynamics, algorithms typically dissipate or accumulate important observables such as energy and momentum over long periods of simulated time [6]. Identification of themore » conservative properties of an algorithm is important for establishing rigorous expectations on the long-term behavior; energy-preserving, symplectic, and volume-preserving methods each have particular implications for the qualitative numerical behavior [6], [7], [8], [9], [10] and [11].« less
Local soil quality assessment of north-central Namibia: integrating farmers' and technical knowledge
NASA Astrophysics Data System (ADS)
Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.
2018-02-01
Soil degradation is a major threat for farmers of semi-arid north-central Namibia. Soil conservation practices can be promoted by the development of soil quality (SQ) evaluation toolboxes that provide ways to evaluate soil degradation. However, such toolboxes must be adapted to local conditions to reach farmers. Based on qualitative (interviews and soil descriptions) and quantitative (laboratory analyses) data, we developed a set of SQ indicators relevant for our study area that integrates farmers' field experiences (FFEs) and technical knowledge. We suggest using participatory mapping to delineate soil units (Oshikwanyama soil units, KwSUs) based on FFEs, which highlight mostly soil properties that integrate long-term productivity and soil hydrological characteristics (i.e. internal SQ). The actual SQ evaluation of a location depends on the KwSU described and is thereafter assessed by field soil texture (i.e. chemical fertility potential) and by soil colour shade (i.e. SOC status). This three-level information aims to reveal SQ improvement potential by comparing, for any location, (a) estimated clay content against median clay content (specific to KwSU) and (b) soil organic status against calculated optimal values (depends on clay content). The combination of farmers' and technical assessment cumulates advantages of both systems of knowledge, namely the integrated long-term knowledge of the farmers and a short- and medium-term SQ status assessment. The toolbox is a suggestion for evaluating SQ and aims to help farmers, rural development planners and researchers from all fields of studies understanding SQ issues in north-central Namibia. This suggested SQ toolbox is adapted to a restricted area of north-central Namibia, but similar tools could be developed in most areas where small-scale agriculture prevails.
NASA Astrophysics Data System (ADS)
Franke, Jasper G.; Werner, Johannes P.; Donner, Reik V.
2017-11-01
Obtaining reliable reconstructions of long-term atmospheric circulation changes in the North Atlantic region presents a persistent challenge to contemporary paleoclimate research, which has been addressed by a multitude of recent studies. In order to contribute a novel methodological aspect to this active field, we apply here evolving functional network analysis, a recently developed tool for studying temporal changes of the spatial co-variability structure of the Earth's climate system, to a set of Late Holocene paleoclimate proxy records covering the last two millennia. The emerging patterns obtained by our analysis are related to long-term changes in the dominant mode of atmospheric circulation in the region, the North Atlantic Oscillation (NAO). By comparing the time-dependent inter-regional linkage structures of the obtained functional paleoclimate network representations to a recent multi-centennial NAO reconstruction, we identify co-variability between southern Greenland, Svalbard, and Fennoscandia as being indicative of a positive NAO phase, while connections from Greenland and Fennoscandia to central Europe are more pronounced during negative NAO phases. By drawing upon this correspondence, we use some key parameters of the evolving network structure to obtain a qualitative reconstruction of the NAO long-term variability over the entire Common Era (last 2000 years) using a linear regression model trained upon the existing shorter reconstruction.
Effectiveness of a social robot, "Paro," in a VA long-term care setting.
Lane, Geoffrey W; Noronha, Delilah; Rivera, Alexandra; Craig, Kathy; Yee, Christina; Mills, Brent; Villanueva, Eimee
2016-08-01
Interest in animal assisted interventions (AAI) has grown over the years, but acceptance of AAI by the clinical and research community has been hampered by safety, hygiene, and logistical concerns. Advances in the field of social robotics have provided a promising route to deliver AAI while avoiding these aforementioned obstacles. Although there has been promising initial research on social robotics in older adults, to date there has been no such research conducted with a veteran population. The present pilot study followed 23 veteran residents of a Veterans Affairs (VA) geropsychiatric long-term care facility over the span of approximately a year and a half. It was found that use of Paro, a social robot, resulted in increased observed positive affective and behavioral indicators, with concomitant decreases observed in negative affective and behavioral indicators. The authors concluded that Paro is likely an effective nonpharmacological approach for managing dementia-related mood and behavior problems with veterans in VA long term care facilities. They additionally observed that Paro is best presented to residents who are relatively calm and approachable, as opposed to actively exhibiting behavior or mood problems. Future research directions are discussed in light of both the positive results noted and the inherent limitations of our pilot study. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Ma, W.; Ma, Y.; Hu, Z.; Zhong, L.
2017-12-01
In this study, a land-atmosphere model was initialized by ingesting AMSR-E products, and the results were compared with the default model configuration and with in situ long-term CAMP/Tibet observations. Firstly our field observation sites will be introduced based on ITPCAS (Institute of Tibetan Plateau Research, Chinese Academy of Sciences). Then, a land-atmosphere model was initialized by ingesting AMSR-E products, and the results were compared with the default model configuration and with in situ long-term CAMP/Tibet observations. The differences between the AMSR-E initialized model runs with the default model configuration and in situ data showed an apparent inconsistency in the model-simulated land surface heat fluxes. The results showed that the soil moisture was sensitive to the specific model configuration. To evaluate and verify the model stability, a long-term modeling study with AMSR-E soil moisture data ingestion was performed. Based on test simulations, AMSR-E data were assimilated into an atmospheric model for July and August 2007. The results showed that the land surface fluxes agreed well with both the in situ data and the results of the default model configuration. Therefore, the simulation can be used to retrieve land surface heat fluxes from an atmospheric model over the Tibetan Plateau.
NASA Astrophysics Data System (ADS)
Braban, Christine; Tang, Sim; Bealey, Bill; Roberts, Elin; Stephens, Amy; Galloway, Megan; Greenwood, Sarah; Sutton, Mark; Nemitz, Eiko; Leaver, David
2017-04-01
Ambient ammonia measurements have been undertaken both in the atmosphere to understand sources, concentrations at background and vulnerable ecosystems and for long term monitoring of concentrations. As a pollutant which is projected to increase concentration in the coming decades with significant policy challenges to implementing mitigation strategies it is useful to assess what has been measured, where and why. In this study a review of the literature, has shown that ammonia measurements are frequently not publically reported and in general not reposited in the open data centres, available for research. The specific sectors where measurements have been undertaken are: agricultural point source assessments, agricultural surface exchange measurements, sensitive ecosystem monitoring, landscape/regional studies and governmental long term monitoring. Less frequently ammonia is measured as part of an intensive atmospheric chemistry field campaign. Technology is developing which means a shift from chemical denuder methods to spectroscopic techniques may be possible, however chemical denuding techniques with off-line laboratory analysis will likely be an economical approach for some time to come. This paper reviews existing datasets from the different sectors of research and integrates them for a global picture to allow both a long term understanding and facilitate comparison with future measurements.
ERIC Educational Resources Information Center
Majerus, Steve; D'Argembeau, Arnaud
2011-01-01
Many studies suggest that long-term lexical-semantic knowledge is an important determinant of verbal short-term memory (STM) performance. This study explored the impact of emotional valence on word immediate serial recall as a further lexico-semantic long-term memory (LTM) effect on STM. This effect is particularly interesting for the study of…
Chapin, Thomas
2015-01-01
Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are not well suited for long-term sampling in remote areas or in freezing conditions. There is a critical need for low-cost, long-duration, high-frequency water sampling technology to improve our understanding of the geochemical response to temporally variable processes. This review article will examine recent developments in automated water sampler technology and utilize selected field data from acid mine drainage studies to illustrate the utility of high-frequency, long-duration water sampling.
Creative treatment of bipolar disorders.
Tavčar, Rok
2015-09-01
Bipolar disorder is a mental disorder with chronic and remitting course. The disorder is related to high mortality and severely impairs everyday functioning. Therefore a scientifically sound and practical approach to treatment is needed. Making a long-term treatment plan usually also demands some creativity. The patient is interested in a number of issues, from the choice of therapy in acute phases to long-term treatment. Usual questions are how long shall I take the medications, do I really need all those pills or can we decrease the dosage of some drugs? This paper discussed the above mentioned questions in light of latest publications in this field.
Butman, Bradford; Bothner, Michael H.; Alexander, P. Soupy; Lightsom, Frances L.; Martini, Marinna A.; Gutierrez, Benjamin T.; Strahle, William S.
2004-01-01
This data report presents long-term oceanographic observations made in western Massachusetts Bay at two locations: (1) 42 deg 22.6' N., 70 deg 47.0' W. (Site A, 33 m water depth) from December 1989 through December 2002 (figure 1), and (2) 42 deg 9.8' N., 70 deg 38.4' W. (Site B, 21 m water depth) from October 1997 through December 2002. Site A is approximately 1 km south of the new ocean outfall that began discharging treated sewage effluent from the Boston metropolitan area into Massachusetts Bay on September 6, 2000. These long-term oceanographic observations have been collected by the U.S. Geological Survey (USGS) in partnership with the Massachusetts Water Resources Authority (MWRA) and with logistical support from the U.S. Coast Guard (USCG - http://www.uscg.mil). This report presents time series data through December 2002, updating a similar report that presented data through December 2000 (Butman and others, 2002). In addition, the Statistics and Mean Flow sections include some new plots and tables and the format of the report has been streamlined by combining yearly figures into single .pdfs. Figure 1 (PDF format) The long-term measurements are planned to continue at least through 2005. The long-term oceanographic observations at Sites A and B are part of a USGS study designed to understand the transport and long-term fate of sediments and associated contaminants in the Massachusetts bays. (See http://woodshole.er.usgs.gov/project-pages/bostonharbor/ and Butman and Bothner, 1997.) The long-term observations document seasonal and inter-annual changes in currents, hydrography, and suspended-matter concentration in western Massachusetts Bay, and the importance of infrequent catastrophic events, such as major storms or hurricanes, in sediment resuspension and transport. They also provide observations for testing numerical models of circulation. This data report presents a description of the field program and instrumentation, an overview of the data through summary plots and statistics, and the data in NetCDF and ASCII format for the period December 1989 through December 2002 for Site A and October 1997 through December 2002 for Site B. The objective of this report is to make the data available in digital form and to provide summary plots and statistics to facilitate browsing of the long-term data set.
NASA Astrophysics Data System (ADS)
Lapusta, N.
2011-12-01
Studying earthquake source processes is a multidisciplinary endeavor involving a number of subjects, from geophysics to engineering. As a solid mechanician interested in understanding earthquakes through physics-based computational modeling and comparison with observations, I need to educate and attract students from diverse areas. My CAREER award has provided the crucial support for the initiation of this effort. Applying for the award made me to go through careful initial planning in consultation with my colleagues and administration from two divisions, an important component of the eventual success of my path to tenure. Then, the long-term support directed at my program as a whole - and not a specific year-long task or subject area - allowed for the flexibility required for a start-up of a multidisciplinary undertaking. My research is directed towards formulating realistic fault models that incorporate state-of-the-art experimental studies, field observations, and analytical models. The goal is to compare the model response - in terms of long-term fault behavior that includes both sequences of simulated earthquakes and aseismic phenomena - with observations, to identify appropriate constitutive laws and parameter ranges. CAREER funding has enabled my group to develop a sophisticated 3D modeling approach that we have used to understand patterns of seismic and aseismic fault slip on the Sunda megathrust in Sumatra, investigate the effect of variable hydraulic properties on fault behavior, with application to Chi-Chi and Tohoku earthquake, create a model of the Parkfield segment of the San Andreas fault that reproduces both long-term and short-term features of the M6 earthquake sequence there, and design experiments with laboratory earthquakes, among several other studies. A critical ingredient in this research program has been the fully integrated educational component that allowed me, on the one hand, to expose students from different backgrounds to the multidisciplinary knowledge required for research in my group and, on the other hand, to communicate the field insights to a broader community. Newly developed course on Dynamic Fracture and Frictional Faulting has combined geophysical and engineering knowledge at the forefront of current research activities relevant to earthquake studies and involved students in these activities through team-based course projects. The course attracts students from more than ten disciplines and received a student rating of 4.8/5 this past academic year. In addition, the course on Continuum Mechanics was enriched with geophysical references and examples. My group has also been visiting physics classrooms in a neighboring public school that serve mostly underrepresented minorities. The visits were beneficial not only to the high school students but also for graduate students and postdocs in my group, who got experience in presenting their field in a way accessible for the general public. Overall, the NSF CAREER award program through the Geosciences Directorate (NSF official Eva E. Zanzerkia) has significantly facilitated my development as a researcher and educator and should be either maintained or expanded.
A bulk superconducting MgB2 cylinder for holding transversely polarized targets
NASA Astrophysics Data System (ADS)
Statera, M.; Balossino, I.; Barion, L.; Ciullo, G.; Contalbrigo, M.; Lenisa, P.; Lowry, M. M.; Sandorfi, A. M.; Tagliente, G.
2018-02-01
An innovative solution is being pursued for the challenging magnetic problem of producing an internal transverse field around a polarized target, while shielding out an external longitudinal field from a detector. A hollow bulk superconductor can trap a transverse field that is present when cooled through its transition temperature, and also shield its interior from any subsequent field changes. A feasibility study with a prototype bulk MgB2 superconducting cylinder is described. Promising measurements taken of the interior field retention and exterior field exclusion, together with the corresponding long-term stability performance, are reported. In the context of an electron scattering experiment, such a solution minimizes beam deflection and the energy loss of reaction products, while also eliminating the heat load to the target cryostat from current leads that would be used with conventional electromagnets.
Curve numbers for long-term no-till corn and agricultural practices with high watershed infiltration
USDA-ARS?s Scientific Manuscript database
The Curve Number (CN) method is an engineering and land management tool for estimating surface runoff from rainstorms. There are few watershed runoff records available during which a no-till crop was growing and hence there are few field-measured CN values. We investigated CN under continuous long-...
Jefimova, Jekaterina; Irha, Natalya; Reinik, Janek; Kirso, Uuve; Steinnes, Eiliv
2014-05-15
The leaching behavior of selected polycyclic aromatic hydrocarbons (PAHs) from an oil shale processing waste deposit was monitored during 2005-2009. Samples were collected from the deposit using a special device for leachate sampling at field conditions without disturbance of the upper layers. Contents of 16 priority PAHs in leachate samples collected from aged and fresh parts of the deposit were determined by GC-MS. The sum of the detected PAHs in leachates varied significantly throughout the study period: 19-315 μg/l from aged spent shale, and 36-151 μg/l from fresh spent shale. Among the studied PAHs the low-molecular weight compounds phenanthrene, naphthalene, acenaphthylene, and anthracene predominated. Among the high-molecular weight PAHs benzo[a]anthracene and pyrene leached in the highest concentrations. A spent shale deposit is a source of PAHs that could infiltrate into the surrounding environment for a long period of time. Copyright © 2014 Elsevier B.V. All rights reserved.
Zhu, Zhi-Lin; Sun, Xiao-Min; Yu, Gui-Rui; Wen, Xue-Fa; Zhang, Yi-Ping; Han, Shi-Jie; Yan, Jun-Hua; Wang, Hui-Min
2011-11-01
Based on the total radiation and photosynthetically active radiation (PAR) observations with net radiometer (CNR1) and quantum sensor (Li-190SB) in 4 ChinaFLUX forest sites (Changbaishan, Qianyanzhou, Dinghushan, and Xishuangbanna) in 2003-2008, this paper analyzed the uncertainties and the radiometers performance changes in long-term and continuous field observation. The results showed that the 98% accuracy of the total radiation measured with CNR1 (Q(cNR1)) could satisfy the technical criterion for the sites except Xishuangbanna where the Q(CNR1) was averagely about 7% lower than Q(CM11), the radiation measured with high accuracy pyranometer CM11. For most sites, though the temperature had definite effects on the performance of CNR1, the effects were still within the allowable range of the accuracy of the instrument. Besides temperature, the seasonal fog often occurred in tropical rain forests in Xishuangbanna also had effects on the performance of CNR1. Based on the long-term variations of PAR, especially its ratio to total radiation in the 4 sites, it was found that quantum sensor (Li-190SB) had obvious performance attenuation, with the mean annual attenuation rate being about 4%. To correct the observation error caused by Li-190SB, an attempt was made to give a post-correction of the PAR observations, which could basically eliminate the quantum sensor's performance attenuation due to long-term field measurement.
Boreal mire Green House Gas exchange in response to global change perturbations
NASA Astrophysics Data System (ADS)
Nilsson, Mats
2017-04-01
High latitude boreal peatlands contribute importantly to the land-atmosphere-hydrosphere exchange of carbon and GHG, i.e. carbon dioxide, methane and dissolved organic carbon. High latitude biomes are identified as most vulnerable to changing climate. High latitudes are also characterized by a strong seasonality in incoming solar radiation, weather conditions and thus also in biogeochemical processes. The strong seasonality in incoming solar radiation, not to change in response to a changing climate, constitute firm constraints on how changes in air temperature, evapotranspiration and precipitation will affect biogeochemical processes underlying the land atmosphere and land hydrosphere exchange of green house gases. In this presentation I combine data from long-term monitoring, long-term field manipulations and detailed chemical analysis to understand how changes in atmosphere and weather conditions influence the major carbon fluxes of a boreal mire Net Ecosystem Carbon Balance. The long-term monitoring data contains >12 years of continuous Eddy Covariance CO2 data, growing season chamber CH4 data and continuous measurements of discharge export of DOC, CO2 and CH4. Data from long-term field snow removal manipulations and growing season temperature increase manipulations are used to further understand the impact of climate on mire carbon and GHG fluxes. Finally we uses Nuclear Magnetic Spectroscopy (NMR) to reveal how century scale changes in atmospheric CO2 from 300 to 400 pm CO2 and temperature have influenced the net photosynthetic capacity of Sphagnum mosses, the single most important plant genus for boreal mire carbon sequestration.
Combined Experimental and Computational Approach to Predict the Glass-Water Reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, Eric M.; Bacon, Diana H.
2011-10-01
The use of mineral and glass dissolution rates measured in laboratory experiments to predict the weathering of primary minerals and volcanic and nuclear waste glasses in field studies requires the construction of rate models that accurately describe the weathering process over geologic timescales. Additionally, the need to model the long-term behavior of nuclear waste glass for the purpose of estimating radionuclide release rates requires that rate models be validated with long-term experiments. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test B, and pressurized unsaturated flow (PUF)], thereby reducingmore » the duration required to evaluate long-term performance. Currently, the PUF test is the only method that mimics the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitors the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. A one-dimensional reactive chemical transport simulation of glass dissolution and secondary phase formation during a 1.5-year-long PUF experiment was conducted with the Subsurface Transport Over Reactive Multiphases (STORM) code. Results show that parameterization of the computer model by combining direct bench scale laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over the length of the experiment. Over the 1.5-year-long test duration, the rate decreased from 0.2 to 0.01 g/(m2 day) based on B release for low-activity waste glass LAWA44. The observed decrease is approximately two orders of magnitude higher than the decrease observed under static conditions with the SON68 glass (estimated to be a decrease by four orders of magnitude) and suggests that the gel-layer properties are less protective under these dynamic conditions.« less
Combined Experimental and Computational Approach to Predict the Glass-Water Reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, Eric M; Bacon, Diana
2011-01-01
The use of mineral and glass dissolution rates measured in laboratory experiments to predict the weathering of primary minerals and volcanic and nuclear waste glasses in field studies requires the construction of rate models that accurately describe the weathering process over geologic time-scales. Additionally, the need to model the long-term behavior of nuclear waste glass for the purpose of estimating radionuclide release rates requires that rate models are validated with long-term experiments. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test-B, and pressurized unsaturated flow (PUF)], thereby reducing themore » duration required to evaluate long-term performance. Currently, the PUF test is the only method that mimics the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitors the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. A one-dimensional reactive chemical transport simulation of glass dissolution and secondary phase formation during a 1.5-year long PUF experiment was conducted with the subsurface transport over reactive multi-phases code. Results show that parameterization of the computer model by combining direct bench-scale laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over the length of the experiment. Over the 1.5-year long test duration, the rate decreased from 0.2 to 0.01 g/(m2 d) base on B release. The observed decrease is approximately two orders of magnitude higher than the decrease observed under static conditions with the SON68 glass (estimated to be a decrease by 4 orders of magnitude) and suggest the gel-layer properties are less protective under these dynamic conditions.« less
NASA Astrophysics Data System (ADS)
Foley, B. J.; Driscoll, P. E.
2015-12-01
Many factors have conspired to make Earth a home to complex life. Earth has abundant water due to a combination of factors, including orbital distance and the climate regulating feedbacks of the long-term carbon cycle. Earth has plate tectonics, which is crucial for maintaining long-term carbon cycling and may have been an important energy source for the origin of life in seafloor hydrothermal systems. Earth also has a strong magnetic field that shields the atmosphere from the solar wind and the surface from high-energy particles. Synthesizing recent work on these topics shows that water, a temperate climate, plate tectonics, and a strong magnetic field are linked together through a series of negative feedbacks that stabilize the system over geologic timescales. Although the physical mechanism behind plate tectonics on Earth is still poorly understood, climate is thought to be important. In particular, temperate surface temperatures are likely necessary for plate tectonics because they allow for liquid water that may be capable of significantly lowering lithospheric strength, increase convective stresses in the lithosphere, and enhance the effectiveness of "damage" processes such as grainsize reduction. Likewise, plate tectonics is probably crucial for maintaining a temperate climate on Earth through its role in facilitating the long-term carbon cycle, which regulates atmospheric CO2 levels. Therefore, the coupling between plate tectonics and climate is a feedback that is likely of first order importance for the evolution of rocky planets. Finally, plate tectonics is thought to be important for driving the geodynamo. Plate tectonics efficiently cools the mantle, leading to vigorous thermo-chemical convection in the outer core and dynamo action; without plate tectonics inefficient mantle cooling beneath a stagnant lid may prevent a long-lived magnetic field. As the magnetic field shields a planet's atmosphere from the solar wind, the magnetic field may be important for preserving hydrogen, and therefore water, on the surface. Thus whole planet coupling between the magnetic field, atmosphere, mantle, and core is possible. We lay out the basic physics governing whole planet coupling, and discuss the implications this coupling has for the evolution of rocky planets and their prospects for hosting life.
Splenectomy Fails to Provide Long-Term Protection Against Ischemic Stroke.
Ran, Yuanyuan; Liu, Zongjian; Huang, Shuo; Shen, Jiamei; Li, Fengwu; Zhang, Wenxiu; Chen, Chen; Geng, Xiaokun; Ji, Zhili; Du, Huishan; Hu, Xiaoming
2018-06-01
Splenectomy before or immediately after stroke provides early brain protection. This study aims to explore the effect of splenectomy on long-term neurological recovery after stroke, which is currently lacking in the field. Adult male rats were randomized into splenectomy or sham groups and then subjected to 90 min of middle cerebral artery occlusion (MCAO). Spleen was removed right upon reperfusion or 3d after MCAO. Infarct volume, neurological functions, and peripheral immune cell populations were assessed up to 28d after stroke. The results show that delayed removal of spleen did not reduce brain tissue loss and showed no effect on sensorimotor function (Rotarod, beam balance, forelimb placing, grid walk, and adhesive removal tests) or cognitive function (Morris water maze). Spleen removal immediately upon reperfusion, although significantly reduced the infarct size and immune cell infiltration 3d after MCAO, also failed to promote long-term recovery. Flow cytometry analysis demonstrated that immediate splenectomy after MCAO resulted in a prolonged decrease in the percentage of CD3 + CD4 + and CD3 + CD8 + T cells in total lymphocytes as compared to non-splenectomy MCAO rats. In contrast, the percentage of CD3 - CD45RA + B cells was significantly elevated after splenectomy. As a result, the ratio of T/B cells was significantly reduced in stroke rats with splenectomy. In conclusion, delayed splenectomy failed to provide long-term protection to the ischemic brain or improve functional recovery. The acute neuroprotective effect achieved by early splenectomy after stroke cannot last for long term. This loss of neuroprotection might be related to the prolonged disturbance in the T cell to B cell ratio.
Tao, Yuqiang; Yu, Jing; Xue, Bin; Yao, Shuchun; Wang, Sumin
2017-04-01
Hydrophobic organic contaminants (HOCs) are toxic and ubiquitous in aquatic environments and pose great risks to aquatic organisms. Bioaccumulation by plankton is the first step for HOCs to enter aquatic food webs. Trophic status is considered to dominate variations in bioaccumulation of HOCs in plankton in temperate and frigid deep oligotrophic waters. However, long-term driving factors for bioaccumulation of HOCs in planktonic food webs of subtropical shallow eutrophic waters have not been well investigated. China has the largest subtropical lake density in the Northern Hemisphere. Due to limited field data, long-term variations in the bioaccumulation of HOCs in these lakes are almost unknown. Here we take Lake Xuanwu as an example to investigate long-term variations in the bioaccumulation, and biomagnification of polycyclic aromatic hydrocarbon (PAHs) in planktonic food webs of subtropical shallow eutrophic lakes in China, and elucidate the driving factors. Our results indicate that temperature rather than nutrients dominates long-term dynamics of planktonic biomass in this lake. Precipitation significantly enhances the concentrations of the PAHs, and total suspended particles, and consequently affects the distribution of the PAHs in the water column. Biomass dilution induced by temperature dominates bioaccumulation of the PAHs by both phytoplankton and zooplankton (copepods and cladocerans). Biomagnification of the PAHs from phytoplankton to zooplankton is positively correlated with temperature. Our study suggests that temperature and precipitation drive long-term variations in the bioaccumulation of the PAHs in the planktonic food webs of this subtropical shallow eutrophic lake. Lake Xuanwu has a similar mean annual temperature, annual precipitation, sunshine duration, and nutrient levels as other subtropical shallow eutrophic lakes in China. This study may also help to understand the bioaccumulation of HOCs in planktonic food webs of other subtropical shallow eutrophic lakes. Copyright © 2017 Elsevier B.V. All rights reserved.
Yang, Li; Zhang, Chao; Chen, Minhao; Li, Jingxin; Yang, Lei; Huo, Zhaomin; Ahmad, Shahid; Luan, Xiaofeng
2018-04-01
Long-term ecological data can be an effective tool to help ecologists integrate future projections with historical contexts and provide unique insights into the long-term dynamics of endangered species. However, hampered by data limitations, including incomplete and spatially biased data, relatively few studies have used multidecadal datasets or have examined changes in biogeography from a historical perspective. The black-billed capercaillie ( Tetrao urogalloides ) is a large capercaillie (classified as Least Concern [LC] on the IUCN red list) that has undergone a dramatic decline in population during the late 20th century and is considered endangered. Its conservation status is pessimistic, and the species requires immediate protection. Therefore, we supplemented a historical dataset to identify changes in this bird's range and population in northeast China over the long term. The study area spanned Heilongjiang Province, Jilin Province, and the northeast corner of Inner Mongolia in northeast China. We integrated an ecological niche model (BIOMOD2) with long-term ecological data on this species to estimate the magnitude of change in distribution over time. Our results revealed a 35.25% reduction in the current distribution of this species compared to their potential distribution in the 1970s. This decline is expected to continue under climate change. For example, the future range loss was estimated to be 38.79 ± 0.22% (8.64-90.19%), and the actual state could be worse, because the baseline range of the model was greater than the real range in the 2000s, showing a 12.39% overestimation. To overcome this poor outlook, a conservation strategy should be established in sensitive areas, including the southwestern Greater Khingan Mountains and northern Lesser Khingan Mountains. Actions that should be considered include field investigations, establishing a monitor network, designing ecological corridors, and cooperating with local inhabitants, governments, and conservation biologists to improve the conservation of the black-billed capercaillie.
Built-up resilience to climate change in peatlands
NASA Astrophysics Data System (ADS)
Wang, H.; Tian, J.; Ho, M.; Flanagan, N. E.; Vilgalys, R.; Richardson, C. J.
2017-12-01
Peatlands have stored about 30% of global soil carbon over millennia. Most studies suggest that climate change effects, like drought and warming, may decrease C sequestration and increase C loss in peatlands, thus resulting in a positive feedback on climate change. However, the long-term feedback between plant-microbe mediated carbon processes and climate change still remains highly uncertain. Here, we conducted a series of field and lab experiments in southern shrub and northern Sphagnum peatlands to document how previously unrecognized mechanisms regulate the buildup of anti-microbial phenolics, which protects stored carbon directly by reducing phenol oxidase activity during short-term drought, and indirectly through a shift from low-phenolics Sphagnum/herbs to high-phenolics shrubs after long-term moderate drought. We further showed a symbiosis of slow-growing decomposers concomitant with a shift of high-phenolic plants, which increased peat resistance to disturbance. Our results indicate that shrub expansion induced by climate change in boreal peatlands may be a long-term self-adaptive mechanism not only increasing carbon sequestration, but also potentially protecting soil carbon. Therefore, peatlands are highly resilient ecosystems in which the symbiotic adaption of both plants and microbes, triggered by persistent climate change, likely can acclimate to the stressors and maintain their carbon sequestration function and processes.
The effect of the solar motion on the flux of long-period comets
NASA Astrophysics Data System (ADS)
Gardner, E.; Nurmi, P.; Flynn, C.; Mikkola, S.
2011-02-01
The long-term dynamics of Oort cloud comets are studied under the influence of both the radial and the vertical components of the Galactic tidal field. Sporadic dynamical perturbation processes, such as passing stars, are ignored since we aim to study the influence of just the axisymmetric Galactic tidal field on the cometary motion and how it changes in time. We use a model of the Galaxy with a disc, bulge and dark halo, and a local disc density and disc scalelength constrained to fit the best available observational constraints. By integrating a few million of cometary orbits over 1 Gyr, we calculate the time variable flux of Oort cloud comets that enter the inner Solar system for the cases of a constant Galactic tidal field and a realistically varying tidal field, which is a function of the Sun's orbit. The applied method calculates the evolution of the comets by using first-order averaged mean elements. We find that the periodicity in the cometary flux is complicated and quasi-periodic. The amplitude of the variations in the flux is of the order of 30 per cent. The radial motion of the Sun is the chief cause of this behaviour, and should be taken into account when the Galactic influence on the Oort cloud comets is studied.
Modeling of Long-Term Evolution of Hydrophysical Fields of the Black Sea
NASA Astrophysics Data System (ADS)
Dorofeyev, V. L.; Sukhikh, L. I.
2017-11-01
The long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by numerical simulation. The model of the Black Sea circulation has 4.8 km horizontal spatial resolution and 40 levels in z-coordinates. The mixing processes in the upper layer are parameterized by Mellor-Yamada turbulent model. For the sea surface boundary conditions, atmospheric forcing functions were used, provided for the Black Sea region by the Euro mediterranean Center on Climate Change (CMCC) from the COSMO-CLM regional climate model. These data have a spatial resolution of 14 km and a daily temporal resolution. To evaluate the quality of the hydrodynamic fields derived from the simulation, they were compared with in-situ hydrological measurements and similar results from physical reanalysis of the Black Sea.