Reducing Dangerous Effects of Unsymmetrical Dimethyl Hydrazine as a Liquid Propellant by Addition of Hydroxyethylhydrazine, Part II, Performance with Several Oxidizers

NASA Astrophysics Data System (ADS)

Keshavarz, Mohammad Hossein; Ramadan, Alireza; Mousaviazar, Ali; Zali, Abbas; Shokrollahi, Arash

2011-07-01

This work continues the study of suitable binary liquid mixtures of unsymmetrical dimethylhydrazine (UDMH) and hydroxyethylhydrazine (HEH) to reduce the harmful effects of pure UDMH. The synthesized HEH was mixed with UDMH up to 40 wt% of HEH to study the performance and properties of binary liquid mixtures of UDMH/HEH. The existence of strong hydrogen bonding between HEH and UDMH provides low-volatile mixtures of these hydrazine derivatives. The addition of HEH significantly reduces the vapor pressure of UDMH, thus reducing the known UDMH health risk to inhalation exposure. Specific impulse was used to study performance of binary mixture UDMH/HEH with respect to pure UDMH. A binary mixture of UDMH/HEH reacts spontaneously in contact with nitrogen tetroxide, red fuming nitric acid (RFNA), and inhibited red fuming nitric acid (IRFNA).

Compositional Changes and Baking Performance of Rye Dough As Affected by Microbial Transglutaminase and Xylanase.

PubMed

Grossmann, Isabel; Döring, Clemens; Jekle, Mario; Becker, Thomas; Koehler, Peter

2016-07-20

Doughs supplemented with endoxylanase (XYL) and varying amounts of microbial transglutaminase (TG) were analyzed by sequential protein extraction, quantitation of protein fractions and protein types, and determination of water-extractable arabinoxylans. With increasing TG activity, the concentration of prolamins and glutelins decreased and increased, respectively, and the prolamin-to-glutelin ratio strongly declined. The overall amount of extractable protein decreased with increasing TG level showing that cross-linking by TG provided high-molecular-weight protein aggregates. The decrease of the high-molecular-weight arabinoxylan fraction and the concurrent increase of the medium-molecular-weight fraction confirmed the degradation of arabinoxylans by XYL. However, XYL addition did not lead to significant improved cross-linking of rye proteins by TG. Volume and crumb hardness measurements of bread showed increased protein connectivity induced by XYL and TG. Significant positive effects on the final bread quality were especially obtained by XYL addition.

ImmunoChip Study Implicates Antigen Presentation to T Cells in Narcolepsy

PubMed Central

Kornum, Birgitte Rahbek; Kenny, Eimear E.; Trynka, Gosia; Einen, Mali; Rico, Tom J.; Lichtner, Peter; Dauvilliers, Yves; Arnulf, Isabelle; Lecendreux, Michel; Javidi, Sirous; Geisler, Peter; Mayer, Geert; Pizza, Fabio; Poli, Francesca; Plazzi, Giuseppe; Overeem, Sebastiaan; Lammers, Gert Jan; Kemlink, David; Sonka, Karel; Nevsimalova, Sona; Rouleau, Guy; Desautels, Alex; Montplaisir, Jacques; Frauscher, Birgit; Ehrmann, Laura; Högl, Birgit; Jennum, Poul; Bourgin, Patrice; Peraita-Adrados, Rosa; Iranzo, Alex; Bassetti, Claudio; Chen, Wei-Min; Concannon, Patrick; Thompson, Susan D.; Damotte, Vincent; Fontaine, Bertrand; Breban, Maxime; Gieger, Christian; Klopp, Norman; Deloukas, Panos; Wijmenga, Cisca; Hallmayer, Joachim; Onengut-Gumuscu, Suna; Rich, Stephen S.; Winkelmann, Juliane; Mignot, Emmanuel

2013-01-01

Recent advances in the identification of susceptibility genes and environmental exposures provide broad support for a post-infectious autoimmune basis for narcolepsy/hypocretin (orexin) deficiency. We genotyped loci associated with other autoimmune and inflammatory diseases in 1,886 individuals with hypocretin-deficient narcolepsy and 10,421 controls, all of European ancestry, using a custom genotyping array (ImmunoChip). Three loci located outside the Human Leukocyte Antigen (HLA) region on chromosome 6 were significantly associated with disease risk. In addition to a strong signal in the T cell receptor alpha (TRA@), variants in two additional narcolepsy loci, Cathepsin H (CTSH) and Tumor necrosis factor (ligand) superfamily member 4 (TNFSF4, also called OX40L), attained genome-wide significance. These findings underline the importance of antigen presentation by HLA Class II to T cells in the pathophysiology of this autoimmune disease. PMID:23459209

Model for a University-Based Clinical Research Development Infrastructure

PubMed Central

Havermahl, Tamara; LaPensee, Elizabeth; Williams, David; Clauw, Daniel; Parker, Robert A.; Downey, Brad; Liu, Jing; Myles, James

2014-01-01

The Research Development Core (RDC) is housed within the Michigan Institute for Clinical & Health Research (MICHR) at the University of Michigan (U-M). Established in 2006, RDC provides no-cost, in-person consultations to help U-M investigators strengthen their grant proposals. RDC offers investigators feedback and critique on all aspects of their study design, plus partnerships, funding mechanisms and future directions. This article describes RDC’s model and provides data describing the success of its services. The RDC is composed of a multidisciplinary team of professionals in grant development. It is comprised of two senior faculty co-directors from the U-M Medical School, two senior biostatisticians, outside faculty content experts, and RDC administrative staff. Investigators contact RDC to request a consultation and submit advance grant materials for review by the RDC team. During the consultation, investigators explain their project and identify challenges. The RDC team and additional experts offer feedback that is captured in meeting notes and provided to investigators. RDC commitments beyond the meetings are implemented and carefully tracked. Investigators may also request grant editing, budgeting, or proposal submission assistance. Investigators utilizing RDC have been awarded $44.5 million since 2011. The demand for RDC consultations doubled from 2010 to 2011, and reached a high of 131 consultations in 2012. Investigator feedback has been positive: 80% reported RDC had a strong impact on their proposal, and over 90% indicated they would recommend RDC to colleagues. MICHR is committed to providing investigators with RDC services to better ensure strong grant applications and successful research careers. PMID:25340362

USGS Training in Afghanistan: Modern Earthquake Hazards Assessments

NASA Astrophysics Data System (ADS)

Medlin, J. D.; Garthwaite, M.; Holzer, T.; McGarr, A.; Bohannon, R.; Bergen, K.; Vincent, T.

2007-05-01

Afghanistan is located in a tectonically active region where ongoing deformation has generated rugged mountainous terrain, and where large earthquakes occur frequently. These earthquakes can present a significant hazard, not only from strong ground shaking, but also from liquefaction and extensive land sliding. The magnitude 6.1 earthquake of March 25, 2002 highlighted the vulnerability of Afghanistan to such hazards, and resulted in over 1000 fatalities. The USGS has provided the first of a series of Earth Science training courses to the Afghan Geological Survey (AGS). This course was concerned with modern earthquake hazard assessments, and is an integral part of a larger USGS effort to provide a comprehensive seismic-hazard assessment for Afghanistan. Funding for these courses is provided by the US Agency for International Development Afghanistan Reconstruction Program. The particular focus of this training course, held December 2-6, 2006 in Kabul, was on providing a background in the seismological and geological methods relevant to preparing for future earthquakes. Topics included identifying active faults, modern tectonic theory, geotechnical measurements of near-surface materials, and strong-motion seismology. With this background, participants may now be expected to educate other members of the community and be actively involved in earthquake hazard assessments themselves. The December, 2006, training course was taught by four lecturers, with all lectures and slides being presented in English and translated into Dari. Copies of the lectures were provided to the students in both hardcopy and digital formats. Class participants included many of the section leaders from within the AGS who have backgrounds in geology, geophysics, and engineering. Two additional training sessions are planned for 2007, the first entitled "Modern Concepts in Geology and Mineral Resource Assessments," and the second entitled "Applied Geophysics for Mineral Resource Assessments."

Effects of gender, age, family support, and treatment on perceived stress and coping of patients with type 2 diabetes mellitus.

PubMed

Hara, Yoriko; Hisatomi, Mizuho; Ito, Hisao; Nakao, Motoyuki; Tsuboi, Koji; Ishihara, Yoko

2014-01-01

We previously found that the empowerment of patients with type 2 diabetes mellitus can be strongly affected by gender and age in addition to self-managed diet and exercise behaviors and treatment. This study was to examine the effects of gender, age, family support, and treatment on the perceived stress and coping of patients with type 2 diabetes mellitus living with family. A survey was conducted of 140 adults with type 2 diabetes mellitus who were living with family. There was no significant difference in hemoglobin A1c (HbA1c) between male and female. Perceived stress and coping were measured with the Japanese version of the Appraisal of Diabetes Scale and the Lazarus Type Stress Coping Inventory. Stepwise regression analysis and path analysis were performed to identify factors that affect the perceived stress and coping of patients. (1) Perceived stress and coping were strongly affected by gender. (2) Perceived stress and coping were affected by age for males, but perceived stress was not affected by age for females. However, females showed a greater "psychological impact of diabetes" than did males. Females aged between 50 and 69 years engaged in active problem solving, but awareness of diabetes was low. (3) Treatment regimens had an effect on HbA1c for both sexes, and diet therapy affected the awareness of diabetes of males and coping of females. (4) For females, "sense of self-control" was strongly associated with coping, and those who were living with non-spouse family members had a greater psychological impact of diabetes than those living with only their spouse. (5) For males, coping was strongly affected by living with their spouse. The results suggest that perceived stress, coping, and diet regimen are deeply associated with gender and age and that a male with type 2 diabetes mellitus living with his spouse is strongly dependent on support from the spouse. It is important to take into account gender, age, and family environment to provide patients with an individualized approach to addressing perceived stress and to provide education program for coping that can maximize treatment and maintain better, continuous glycemic control.

Laser capture microdissection-microarray analysis of focal segmental glomerulosclerosis glomeruli.

PubMed

Bennett, Michael R; Czech, Kimberly A; Arend, Lois J; Witte, David P; Devarajan, Prasad; Potter, S Steven

2007-01-01

Focal segmental glomerulosclerosis (FSGS) is a major cause of end-stage renal disease. In this report we used laser capture microdissection to purify diseased glomeruli, and microarrays to provide universal gene expression profiles. The results provide a deeper understanding of the molecular mechanisms of the disease process and suggest novel therapeutic strategies. Consistent with earlier studies, molecular markers of the differentiated podocyte, including WT1, nephrin, and VEGF, were dramatically downregulated in the diseased glomerulus. We also observed multiple changes consistent with increased TGF-beta signaling, including elevated expression of TGF-beta(2), TGF-beta(3), SMAD2, TGF-beta(1) receptor, and thrombospondin. In addition, there was relatively low level expression of Csf1r, a marker of macrophages, but elevated expression of the chemokines CXCL1, CXCL2, CCL3, and CXCL14. We also observed strongly upregulated expression of Sox9, a transcription factor that can drive a genetic program of chondrogenesis and fibrosis. Further, the gene with the greatest fold increase in expression in the diseased glomerulus was osteopontin, which has been previously strongly implicated in kidney fibrosis in the unilateral ureteral obstruction mouse model. These results confirm old findings, and indicate the involvement of new genetic pathways in the cause and progression of FSGS. Copyright 2007 S. Karger AG, Basel.

Airborne ultrafine particles in a naturally ventilated metro station: Dominant sources and mixing state determined by particle size distribution and volatility measurements.

PubMed

Mendes, Luís; Gini, Maria I; Biskos, George; Colbeck, Ian; Eleftheriadis, Konstantinos

2018-08-01

Ultrafine particle number concentrations and size distributions were measured on the platform of a metro station in Athens, Greece, and compared with those recorded at an urban background station. The volatility of the sampled particles was measured in parallel, providing further insights on the mixing state and composition of the sampled particles. Particle concentration exhibited a mean value of 1.2 × 10 4 # cm -3 and showed a weak correlation with train passage frequency, but exhibited a strong correlation with urban background particle concentrations. The size distribution appears to be strongly influenced by outdoor conditions, such as the morning traffic rush hour and new particle formation events observed at noon. The aerosol in the metro was externally mixed throughout the day, with particle populations being identified (1) as fully refractory particles being more dominant during the morning traffic rush hours, (2) as core-shell structure particles having a non-volatile core coated with volatile material, and (3) fully volatile particles. The evolution of particle volatility and size throughout the day provide additional support that most nanoparticles in the metro station originate from outdoor urban air. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chemically engineered sulfated glucans from rice bran exert strong antiviral activity at the stage of viral entry.

PubMed

Ray, Bimalendu; Hutterer, Corina; Bandyopadhyay, Shruti S; Ghosh, Kanika; Chatterjee, Udipta R; Ray, Sayani; Zeitträger, Isabel; Wagner, Sabrina; Marschall, Manfred

2013-12-27

Attachment and entry of many viruses are mediated by their affinity for polysaccharides present on the surface of target cells. In this paper, we demonstrate that sulfated glucans isolated from rice (Oryza sativa) can be utilized as experimental drugs exerting strong antiviral activity. In particular, oleum-DMF-based extraction is described as a procedure for the generation of chemically engineered glucans from commercially available rice bran. The one-step procedure has the potential to provide a spectrum of related glucans with varying molecular masses and modifications, including sulfation. The sulfated glucans P444, P445, and P446 possess increased antiviral activity compared to a previously described glucan (S1G). P444, P445, and P446 were highly active against human cytomegalovirus (HCMV), moderately active against other members of the family Herpesviridae, while not active against unrelated viruses. Specific experimentation with HCMV-infected cells provided evidence that antiviral activity was based on inhibition of viral entry and that inhibition occurred in the absence of drug-induced cytotoxicity. These findings underline the high potential of sulfated glucans for antiviral research and drug development. In addition, the procedure described for the efficient transformation of glucan hydroxy groups to sulfate groups may be similarly beneficial for the chemical alteration of other natural products.

Complementary feeding: clinically relevant factors affecting timing and composition.

PubMed

Krebs, Nancy F; Hambidge, K Michael

2007-02-01

Exclusive breastfeeding for the first 6 mo of life followed by optimal complementary feeding are critical public health measures for reducing and preventing morbidity and mortality in young children. Clinical factors, such as birth weight, prematurity, and illness, that affect the iron and zinc requirements of younger infants are discussed. Maternal diet and nutritional status do not have a strong effect on the mineral content of human milk, but physiologic changes in milk and the infants' status determine the dependence of the infant on complementary foods in addition to human milk to meet iron and zinc requirements after 6 mo. The nature of zinc absorption, which is suitably characterized by saturation response modeling, dictates that plant-based diets, which are low in zinc, are associated with low absolute daily absorbed zinc, which is inadequate to meet requirements. Foods with a higher zinc content, such as meats, are much more likely to be sufficient to meet dietary requirements. Current plant-based complementary feeding patterns for older fully breastfed infants in both developed and developing countries pose a risk of zinc deficiency. The strong rationale for the potential benefits of providing meat as an early complementary food, and the examples of successful intervention programs, provide potent incentives to pursue broader implementation programs, with concurrent rigorous evaluation of both efficacy and effectiveness.

Why do some therapists not deal with outcome monitoring feedback? A feasibility study on the effect of regulatory focus and person-organization fit on attitude and outcome.

PubMed

de Jong, Kim; de Goede, Marije

2015-01-01

Despite research on its effectiveness, many therapists still have negative attitudes toward using outcome monitoring feedback. The current study aims to investigate how the perceived match between values of an individual and those of the organization (Person-Organization fit; PO fit), and motivation to prevent failure or to achieve success (regulatory focus) are related to therapists' attitude, attitude changes over time, and outcomes. Therapists (n = 20) filled out a feedback attitude questionnaire at two points in time: before the start of outcome monitoring, and after six months. In addition, they completed measures on PO fit and regulatory focus. PO fit was predictive of outcomes, when feedback was provided, but did not predict therapists' attitude. Therapists with a strong prevention focus (prevent failures), had a more positive attitude toward feedback, but achieved slower symptom reduction in their at risk cases. A strong promotion focus (achieve success) was not predictive of attitude, but did result in faster symptom reduction in at risk patients when feedback was provided. Therapists motivational approach to work and the perceived match with the organization they work for, can influence both their attitude toward outcome monitoring and their outcomes.

Insights on the Cuprate High Energy Anomaly Observed in ARPES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moritz, Brian

2011-08-16

Recently, angle-resolved photoemission spectroscopy has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). The anomaly is present for both hole- and electron-doped cuprates as well as the half-filled parent insulators with different energy scales arising on either side of the phase diagram. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. creating a 'waterfall'-like appearance, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA.more » Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram. We find that the anomaly demarcates a transition, or cross-over, from a quasiparticle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong oxygen character.« less

Statistical Analysis of the Worker Engagement Survey Administered at the Worker Safety and Security Team Festival

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, Adam Christopher

The Worker Safety and Security Team (WSST) at Los Alamos National Laboratory holds an annual festival, WSST-fest, to engage workers and inform them about safety- and securityrelated matters. As part of the 2015 WSST-fest, workers were given the opportunity to participate in a survey assessing their engagement in their organizations and work environments. A total of 789 workers participated in the 23-question survey where they were also invited, optionally, to identify themselves, their organization, and to give open-ended feedback. The survey consisted of 23 positive statements (i.e. “My organization is a good place to work.”) with which the respondent couldmore » express a level of agreement. The text of these statements are provided in Table 1. The level of agreement corresponds to a 5-level Likert scale ranging from “Strongly Disagree” to “Strongly Agree.” In addition to assessing the overall positivity or negativity of the scores, the results were partitioned into several cohorts based on the response meta-data (self-identification, comments, etc.) to explore trends. Survey respondents were presented with the options to identify themselves, their organizations and to provide comments. These options suggested the following questions about the data set.« less

Ultrafast electron-lattice coupling dynamics in VO2 and V2O3 thin films

NASA Astrophysics Data System (ADS)

Abreu, Elsa; Gilbert Corder, Stephanie N.; Yun, Sun Jin; Wang, Siming; Ramírez, Juan Gabriel; West, Kevin; Zhang, Jingdi; Kittiwatanakul, Salinporn; Schuller, Ivan K.; Lu, Jiwei; Wolf, Stuart A.; Kim, Hyun-Tak; Liu, Mengkun; Averitt, Richard D.

2017-09-01

Ultrafast optical pump-optical probe and optical pump-terahertz probe spectroscopy were performed on vanadium dioxide (VO2) and vanadium sesquioxide (V2O3 ) thin films over a wide temperature range. A comparison of the experimental data from these two different techniques and two different vanadium oxides, in particular a comparison of the spectral weight oscillations generated by the photoinduced longitudinal acoustic modulation, reveals the strong electron-phonon coupling that exists in both materials. The low-energy Drude response of V2O3 appears more amenable than VO2 to ultrafast strain control. Additionally, our results provide a measurement of the temperature dependence of the sound velocity in both systems, revealing a four- to fivefold increase in VO2 and a three- to fivefold increase in V2O3 across the insulator-to-metal phase transition. Our data also confirm observations of strong damping and phonon anharmonicity in the metallic phase of VO2, and suggest that a similar phenomenon might be at play in the metallic phase of V2O3 . More generally, our simple table-top approach provides relevant and detailed information about dynamical lattice properties of vanadium oxides, paving the way to similar studies in other complex materials.

Rrsm: The European Rapid Raw Strong-Motion Database

NASA Astrophysics Data System (ADS)

Cauzzi, C.; Clinton, J. F.; Sleeman, R.; Domingo Ballesta, J.; Kaestli, P.; Galanis, O.

2014-12-01

We introduce the European Rapid Raw Strong-Motion database (RRSM), a Europe-wide system that provides parameterised strong motion information, as well as access to waveform data, within minutes of the occurrence of strong earthquakes. The RRSM significantly differs from traditional earthquake strong motion dissemination in Europe, which has focused on providing reviewed, processed strong motion parameters, typically with significant delays. As the RRSM provides rapid open access to raw waveform data and metadata and does not rely on external manual waveform processing, RRSM information is tailored to seismologists and strong-motion data analysts, earthquake and geotechnical engineers, international earthquake response agencies and the educated general public. Access to the RRSM database is via a portal at http://www.orfeus-eu.org/rrsm/ that allows users to query earthquake information, peak ground motion parameters and amplitudes of spectral response; and to select and download earthquake waveforms. All information is available within minutes of any earthquake with magnitude ≥ 3.5 occurring in the Euro-Mediterranean region. Waveform processing and database population are performed using the waveform processing module scwfparam, which is integrated in SeisComP3 (SC3; http://www.seiscomp3.org/). Earthquake information is provided by the EMSC (http://www.emsc-csem.org/) and all the seismic waveform data is accessed at the European Integrated waveform Data Archive (EIDA) at ORFEUS (http://www.orfeus-eu.org/index.html), where all on-scale data is used in the fully automated processing. As the EIDA community is continually growing, the already significant number of strong motion stations is also increasing and the importance of this product is expected to also increase. Real-time RRSM processing started in June 2014, while past events have been processed in order to provide a complete database back to 2005.

Simultaneous Inference For The Mean Function Based on Dense Functional Data

PubMed Central

Cao, Guanqun; Yang, Lijian; Todem, David

2012-01-01

A polynomial spline estimator is proposed for the mean function of dense functional data together with a simultaneous confidence band which is asymptotically correct. In addition, the spline estimator and its accompanying confidence band enjoy oracle efficiency in the sense that they are asymptotically the same as if all random trajectories are observed entirely and without errors. The confidence band is also extended to the difference of mean functions of two populations of functional data. Simulation experiments provide strong evidence that corroborates the asymptotic theory while computing is efficient. The confidence band procedure is illustrated by analyzing the near infrared spectroscopy data. PMID:22665964

Synthesis of 1D Bragg gratings by a layer-aggregation method.

PubMed

Capmany, José; Muriel, Miguel A; Sales, Salvador

2007-08-15

We present what we believe to be a novel method for the synthesis of complex 1D (fiber and waveguide) Bragg gratings, which is based on an impedance reconstruction layer aggregation technique. The main advantage brought by the method is the possibility of synthesizing structures containing defects or discontinuities of the size of the local period, a feature that is not possible with prior reported methods. In addition, this enhanced spatial resolution allows the synthesis of very strong fiber Bragg grating devices providing convergent solutions. The method directly renders the refractive index profile n(z) as it does not rely on the coupled-mode theory.

Bio-Inspired Metal-Coordination Dynamics: A Unique Tool for Engineering Soft Matter Mechanics

NASA Astrophysics Data System (ADS)

Holten-Andersen, Niels

Growing evidence supports a critical role of metal-coordination in soft biological material properties such as self-healing, underwater adhesion and autonomous wound plugging. Using bio-inspired metal-binding polymers, initial efforts to mimic these properties with metal-coordination crosslinked polymer materials have shown promise. In addition, with polymer network mechanics strongly coupled to coordinate crosslink dynamics material properties can be easily tuned from visco-elastic fluids to solids. Given their exploitation in desirable material applications in Nature, bio-inspired metal-coordinate complex crosslinking provides an opportunity to further advance synthetic polymer materials design. Early lessons from this pursuit are presented.

Optical properties of new wide heterogeneous waveguides with thermo optical shifters.

PubMed

De Leonardis, Francesco; Tsarev, Andrei V; Passaro, Vittorio M

2008-12-22

We present analysis and simulation of novel silicon-on-insulator (SOI) heterogeneous waveguides with thermo-optic phase shifters. New structure design contains a p-n junction on both sides of SOI ridge waveguide with 220 nm x 35 microm silicon core. Strongly mode-dependent optical losses (by additional free charge absorption) provide quasi-singe-mode behavior of wide waveguide with mode size approximately 10 microm. Local heater produces an efficient phase shifting by small temperature increase (DeltaT approximately 2K), switching power (< 40 mW) and switching time (< 10 micros). Mode optical losses are significantly decreased at high heating (DeltaT approximately 120 K).

Parallel implementation of approximate atomistic models of the AMOEBA polarizable model

NASA Astrophysics Data System (ADS)

Demerdash, Omar; Head-Gordon, Teresa

2016-11-01

In this work we present a replicated data hybrid OpenMP/MPI implementation of a hierarchical progression of approximate classical polarizable models that yields speedups of up to ∼10 compared to the standard OpenMP implementation of the exact parent AMOEBA polarizable model. In addition, our parallel implementation exhibits reasonable weak and strong scaling. The resulting parallel software will prove useful for those who are interested in how molecular properties converge in the condensed phase with respect to the MBE, it provides a fruitful test bed for exploring different electrostatic embedding schemes, and offers an interesting possibility for future exascale computing paradigms.

A Survey on Wireless Body Area Networks for eHealthcare Systems in Residential Environments

PubMed Central

Ghamari, Mohammad; Janko, Balazs; Sherratt, R. Simon; Harwin, William; Piechockic, Robert; Soltanpur, Cinna

2016-01-01

Current progress in wearable and implanted health monitoring technologies has strong potential to alter the future of healthcare services by enabling ubiquitous monitoring of patients. A typical health monitoring system consists of a network of wearable or implanted sensors that constantly monitor physiological parameters. Collected data are relayed using existing wireless communication protocols to a base station for additional processing. This article provides researchers with information to compare the existing low-power communication technologies that can potentially support the rapid development and deployment of WBAN systems, and mainly focuses on remote monitoring of elderly or chronically ill patients in residential environments. PMID:27338377

'Strong is the new skinny': A content analysis of #fitspiration images on Instagram.

PubMed

Tiggemann, Marika; Zaccardo, Mia

2018-07-01

'Fitspiration' is an online trend designed to inspire viewers towards a healthier lifestyle by promoting exercise and healthy food. This study provides a content analysis of fitspiration imagery on the social networking site Instagram. A set of 600 images were coded for body type, activity, objectification and textual elements. Results showed that the majority of images of women contained only one body type: thin and toned. In addition, most images contained objectifying elements. Accordingly, while fitspiration images may be inspirational for viewers, they also contain a number of elements likely to have negative effects on the viewer's body image.

A Survey on Wireless Body Area Networks for eHealthcare Systems in Residential Environments.

PubMed

Ghamari, Mohammad; Janko, Balazs; Sherratt, R Simon; Harwin, William; Piechockic, Robert; Soltanpur, Cinna

2016-06-07

Current progress in wearable and implanted health monitoring technologies has strong potential to alter the future of healthcare services by enabling ubiquitous monitoring of patients. A typical health monitoring system consists of a network of wearable or implanted sensors that constantly monitor physiological parameters. Collected data are relayed using existing wireless communication protocols to a base station for additional processing. This article provides researchers with information to compare the existing low-power communication technologies that can potentially support the rapid development and deployment of WBAN systems, and mainly focuses on remote monitoring of elderly or chronically ill patients in residential environments.

On the correlation of angular position with time of occurrence of gamma-ray bursts

NASA Technical Reports Server (NTRS)

Petrosian, Vahe; Efron, Bradley

1995-01-01

Evidence indicating that a large fraction of gamma-ray bursts are repeaters would provide strong support for noncosmological origin of these sources. Wang & Lingenfelter have claimed existance of a correlation between angular position and time of occurrence of bursts. We perform statistical tests and find a marginal evidence for nearby bursts occurring within 4 to 5 days of each other in the BATSE 1B catalog. This evidence is present also in the 2B catalogs, which in addition, shows some marginal evidence for bursts repetition at longer time delays up to the total length of the observations.

On the halophytic nature of mangroves

USGS Publications Warehouse

Krauss, Ken W.; Ball, Marilyn C.

2013-01-01

Scientists have discussed the halophytic nature of intertidal plants for decades, and have generally suggested that inherent differentiation of an obligate halophyte from a facultative halophyte relates strongly to whether the plant can survive in fresh water, and not much else. In this mini-review, we provide additional insight to support the pervasive notion that mangroves as a group are truly facultative halophytes, and thus add discourse to the alternate view that mangroves have an obligate salinity requirement. Indeed, growth and physiological optima are realized at moderate salinity concentrations in mangroves, but we maintain the notion that current evidence suggests that survival is not dependent upon a physiological requirement for salt.

Clinical lesson: eosinophilic oesophagitis, a new diagnosis to swallow.

PubMed

Lamb, C A; Kanakala, V; Stirling, R W; Attwood, S E A

2010-04-01

Eosinophilic oesophagitis (EoE) is a recently described condition that has gained increasing recognition over the past 5 years. Despite this, many clinicians remain unaware of EoE, often leading to diagnostic delay and therefore significant morbidity. The diagnosis of EoE should be considered in any patient with a history of intermittent or continuous dysphagia, or oesophageal food impaction. It should be strongly suspected in young patients, particularly men, presenting with dysphagia and a history of atopy. Here, three patients are presented that highlight common features of EoE. In addition, a clinical review of the worldwide literature is provided to heighten physician awareness and understanding of the condition.

On meteor-generated infrasound. [propagation characteristics during entry into earth atmosphere

NASA Technical Reports Server (NTRS)

Revelle, D. O.

1976-01-01

The characteristics of generation and propagation of infrasonic pressure waves excited during meteor entry into the earth's atmosphere are studied. Existing line source blast wave theory is applied to infrasonic airwave data from four bright fire-balls. It is shown that the strong shock behavior of the blast wave is confined to a cylinderical region with a radius proportional to the product of the meteor Mach number and its diameter. A description of the wave form far from the source is provided. Infrasonic data reported elsewhere are analyzed. All the results should be considered as preliminary, and additional work is under way to refine the estimates obtained.

Including fall prevention for older adults in your trauma injury prevention program--introducing Farewell to Falls.

PubMed

Corman, Ellen

2009-01-01

With data showing that more than 50% of visits to our trauma center for older adults 65 years and older are due to falls, injury prevention programs in trauma centers should be paying more attention to the area of fall prevention for older adults. Farewell to Falls, a free, home-based program of Stanford Hospital and Clinic's trauma service, utilizes a multifaceted approach to help reduce falls. In addition to improving the lives of seniors, the program fulfills a community benefit goal and provides strong hospital marketing opportunities. This program is a benefit to hospitals and the older adults they serve.

Imager for Mars Pathfinder (IMF)

NASA Technical Reports Server (NTRS)

Smith, Peter H.

1994-01-01

The IMP camera is a near-surface sensing experiment with many capabilities beyond those normally associated with an imager. It is fully pointable in both elevation and azimuth with a protected, stowed position looking straight down. Stereo separation is provided with two optical paths; each has a 12-position filter wheel. The primary function of the camera, strongly tied to mission success, is to take a color panorama of the surrounding terrain. IMP requires approximately 120 images to give a complete downward hemisphere from the deployed position. IMP provides the geologist, and everyone else, a view of the local morphology with millimeter-tometer-scale resolution over a broad area. In addition to the general morphology of the scale, IMP has a large compliment of specially chosen filters to aid in both the identification of the mineral types and their degree of weathering.

A gated Thomson parabola spectrometer for improved ion and neutral atom measurements in intense laser produced plasmas

NASA Astrophysics Data System (ADS)

Tata, Sheroy; Mondal, Angana; Sarkar, Soubhik; Lad, Amit D.; Krishnamurthy, M.

2017-08-01

Ions of high energy and high charge are accelerated from compact intense laser produced plasmas and are routinely analysed either by time of flight or Thomson parabola spectrometry. At the highest intensities where ion energies can be substantially large, both these techniques have limitations. Strong electromagnetic pulse noise jeopardises the arrival time measurement, and a bright central spot in the Thomson parabola spectrometer affects the signal to noise ratio of ion traces that approach close to the central spot. We present a gated Thomson parabola spectrometer that addresses these issues and provides an elegant method to improvise ion spectrometry. In addition, we demonstrate that this method provides the ability to detect and measure high energy neutral atoms that are invariably present in most intense laser plasma acceleration experiments.

A gated Thomson parabola spectrometer for improved ion and neutral atom measurements in intense laser produced plasmas.

PubMed

Tata, Sheroy; Mondal, Angana; Sarkar, Soubhik; Lad, Amit D; Krishnamurthy, M

2017-08-01

Ions of high energy and high charge are accelerated from compact intense laser produced plasmas and are routinely analysed either by time of flight or Thomson parabola spectrometry. At the highest intensities where ion energies can be substantially large, both these techniques have limitations. Strong electromagnetic pulse noise jeopardises the arrival time measurement, and a bright central spot in the Thomson parabola spectrometer affects the signal to noise ratio of ion traces that approach close to the central spot. We present a gated Thomson parabola spectrometer that addresses these issues and provides an elegant method to improvise ion spectrometry. In addition, we demonstrate that this method provides the ability to detect and measure high energy neutral atoms that are invariably present in most intense laser plasma acceleration experiments.

Twenty Years of Evidence on the Outcomes of Malpractice Claims

PubMed Central

2008-01-01

Two decades of social science research on the outcomes of medical malpractice claims show malpractice outcomes bear a surprisingly good correlation with the quality of care provided to the patient as judged by other physicians. Physicians win 80% to 90% of the jury trials with weak evidence of medical negligence, approximately 70% of the borderline cases, and even 50% of the trials in cases with strong evidence of medical negligence. With only one exception, all of the studies of malpractice settlements also find a correlation between the odds of a settlement payment and the quality of care provided to the plaintiff. Between 80% and 90% of the claims rated as defensible are dropped or dismissed without payment. In addition, the amount paid in settlement drops as the strength of the patient’s evidence weakens. PMID:19048355

Successful psychotherapy for psychogenic seizures in men.

PubMed

Quinn, Maria Clare; Schofield, Margot J; Middleton, Warwick

2012-01-01

This qualitative study examined factors contributing to the development and successful treatment of psychogenic non-epileptic seizures (PNES), in civilian men. In-depth interviews were conducted with therapist-client dyads comprising two male clients who had been successfully treated for PNES and their therapists. A theory-building case study approach provided evidence that those factors known to contribute to PNES and other somatoform symptoms in females and in males engaged in war also contributed to these symptoms in these two civilian males. In addition, PNES in these civilian males occurred in contexts where masculine identity was developmentally curtailed and socially constrained. Successful treatments occurred in long-term therapeutic relationships that sanctioned verbal expression of strong emotion and provided the attunement necessary for development of a robust masculine identity. These findings have implications for the funding of therapy, and training of therapists.

World Health Organization strong recommendations based on low-quality evidence (study quality) are frequent and often inconsistent with GRADE guidance.

PubMed

Alexander, Paul E; Brito, Juan P; Neumann, Ignacio; Gionfriddo, Michael R; Bero, Lisa; Djulbegovic, Benjamin; Stoltzfus, Rebecca; Montori, Victor M; Norris, Susan L; Schünemann, Holger J; Guyatt, Gordon H

2016-04-01

In 2007 the World Health Organization (WHO) adopted the GRADE system for development of public health guidelines. Previously we found that many strong recommendations issued by WHO are based on evidence for which there is only low or very low confidence in the estimates of effect (discordant recommendations). GRADE guidance indicates that such discordant recommendations are rarely appropriate but suggests five paradigmatic situations in which discordant recommendations may be warranted. We sought to provide insight into the many discordant recommendations in WHO guidelines. We examined all guidelines that used the GRADE method and were approved by the WHO Guideline Review Committee between 2007 and 2012. Teams of reviewers independently abstracted data from eligible guidelines and classified recommendations either into one of the five paradigms for appropriately-formulated discordant recommendations or into three additional categories in which discordant recommendations were inconsistent with GRADE guidance: 1) the evidence warranted moderate or high confidence (a misclassification of evidence) rather than low or very low confidence; 2) good practice statements; or 3) uncertainty in the estimates of effect would best lead to a conditional (weak) recommendation. The 33 eligible guidelines included 160 discordant recommendations, of which 98 (61.3%) addressed drug interventions and 132 (82.5%) provided some rationale (though not entirely explicit at times) for the strong recommendation. Of 160 discordant recommendations, 25 (15.6%) were judged consistent with one of the five paradigms for appropriate recommendations; 33 (21%) were based on evidence warranting moderate or high confidence in the estimates of effect; 29 (18%) were good practice statements; and 73 (46%) warranted a conditional, rather than a strong recommendation. WHO discordant recommendations are often inconsistent with GRADE guidance, possibly threatening the integrity of the process. Further training in GRADE methods for WHO guideline development group members may be necessary, along with further research on what motivates the formulation of such recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

Copepods in Turbid Shallow Soda Lakes Accumulate Unexpected High Levels of Carotenoids

PubMed Central

Schneider, Tobias; Herzig, Alois; Koinig, Karin A.; Sommaruga, Ruben

2012-01-01

Carotenoids are protective pigments present in many aquatic organisms that reduce the photooxidative stress induced by short-wavelenght solar radiation, yet increase their susceptibility to predators. Arctodiaptomus spinosus, a calanoid copepod typically found in many fishless shallow soda lakes, shows large between-lake differences in pigmentation. Here, we attribute these differences to the environmental state of these ecosystems, namely, ‘dark water’ lakes with submersed vegetation and turbid ‘white’ lakes lacking macrophytes. Copepod carotenoid concentration in the turbid ‘white’ lakes was significantly (about 20-fold) higher than in the ‘dark water’ ones, although the latter systems were characterized by higher transparency. In addition, males had on a dry weight basis around three times higher carotenoid concentrations than females. Mycosporine-like amino acids (direct UV screening substances) were found in all cases, but in low concentration. The environmental conditions in these ecosystems were largely shaped by the presence/absence of submersed macrophytes Thus, in the turbid lakes, the strong wind-driven mixis allows for copepods to be brought to the surface and being exposed to solar radiation, whereas in ‘dark water’ ones, macrophytes reduce water turbulence and additionally provide shelter. Our results explain the counter-intuitive notion of strong red pigmentation in copepods from a turbid ecosystem and suggest that factors other than high UV transparency favor carotenoid accumulation in zooplankton. PMID:22916208

Brentuximab vedotin for treatment of non-Hodgkin lymphomas: A systematic review

PubMed Central

Berger, Garrett K.; McBride, Ali; Lawson, Stephanie; Royball, Kelsey; Yun, Seongseok; Gee, Kevin; Riaz, Irbaz Bin; Saleh, Ahlam A.; Puvvada, Soham; Anwer, Faiz

2016-01-01

Background Brentuximab vedotin (BV) is an antibody-drug conjucate (ADC) comprising a CD30-directed antibody, conjugated to the microtubule-disrupting agent MMAE via a protease cleavable linker. BV is FDA approved for use in relapsed classical Hodgkin lymphoma (HL) and relapsed systemic anaplastic large cell lymphoma (sALCL). There are multiple publications for its utility in other malignancies such as diffuse large B-cell lymphoma (DLBCL), mycosis fungoides (MF), Sézary syndrome (SS), T-cell lymphomas (TCL), primary mediastinal lymphoma (PMBL), and post-transplant lymphoproliferative disorders (PTLD). We believe that BV could potentially provide a strong additional treatment option for patients suffering from NHL. Objective Perform a systematic review on the use of BV in non-Hodgkin lymphoma (NHL) and other CD30+ malignancies in humans. Data sources We searched various databases including PubMed (1946–2015), EMBASE (1947–2015), and Cochrane Central Register of Controlled Trials (1898–2015). Eligibility criteria Inclusion criteria specified all studies and case reports of NHLs in which BV therapy was administered. Included studies A total of 28 articles met these criteria and are summarized in this manuscript. Conclusion Our findings indicate that BV induces a variety of responses, largely positive in nature and variable between NHL subtypes. With additional, properly powered prospective studies, BV may prove to be a strong candidate in the treatment of various CD30+ malignancies. PMID:28010897

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, Antony, E-mail: antony@cosmologist.info

Rayleigh scattering from neutral hydrogen during and shortly after recombination causes the CMB anisotropies to be significantly frequency dependent at high frequencies. This may be detectable with Planck, and would be a strong signal in any future space-based CMB missions. The later peak of the Rayleigh visibility compared to Thomson scattering gives an increased large-scale CMB polarization signal that is a greater than 4% effect for observed frequencies ν ∼> 500GHz. There is a similar magnitude suppression on small scales from additional damping. Due to strong correlation between the Rayleigh and primary signal, measurement of the Rayleigh component is limitedmore » by noise and foregrounds, not cosmic variance of the primary CMB, and should observable over a wide range of angular scales at frequencies 200GHz ∼< ν ∼< 800GHz. I give new numerical calculations of the temperature and polarization power spectra, and show that future CMB missions could measure the temperature Rayleigh cross-spectrum at high precision, detect the polarization from Rayleigh scattering, and also accurately determine the cross-spectra between the Rayleigh temperature signal and primary polarization. The Rayleigh scattering signal may provide a powerful consistency check on recombination physics. In principle it can be used to measure additional horizon-scale primordial perturbation modes at recombination, and distinguish a significant tensor mode B-polarization signal from gravitational lensing at the power spectrum level.« less

Complementary cereals and legumes for health: Synergistic interaction of sorghum flavones and cowpea flavonols against LPS-induced inflammation in colonic myofibroblasts.

PubMed

Agah, Shima; Kim, Hyemee; Mertens-Talcott, Susanne U; Awika, Joseph M

2017-07-01

Cereals and legumes are traditionally consumed together in many cultures, and may provide complementary health benefits beyond what is known about improved indispensable amino acid intake. Here, we use an in vitro model of inflammatory pathways to investigate whether the different flavonoids in sorghum and cowpea could synergistically reduce inflammation. Interactive effect of combining apigenin and quercetin, as well as extracts (70% acetone, v/v) from a flavone-dominated white sorghum and flavonol-dominated white cowpea, against LPS-induced NF-κB and downstream cytokines (TNF-α, IL-6, IL-8) gene and protein expression was evaluated using the CCD18Co colon myofibroblasts. Combination of apigenin and quercetin, and sorghum and cowpea extracts synergistically downregulated LPS-induced NF-κB gene and protein expression in a dose-dependent manner, with additive effect producing IC 50 values that were 14.6 and 14.0 times, respectively, higher than 1:1 combined treatments. Similar strong synergistic interactions were observed for the downstream cytokines (IC 50 values for additive effect 8.3-21 times higher than combined treatments). Furthermore, the ratios of the different combined treatments significantly affected the magnitude of synergy. Combining the structurally related cereal flavones and legume flavonols elicit strong synergistic anti-inflammatory response in LPS-stimulated nonmalignant colonocytes, likely by targeting interdependent mechanisms. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Near-infrared diffuse interstellar bands in APOGEE telluric standard star spectra . Weak bands and comparisons with optical counterparts

NASA Astrophysics Data System (ADS)

Elyajouri, M.; Lallement, R.; Monreal-Ibero, A.; Capitanio, L.; Cox, N. L. J.

2017-04-01

Aims: Information on the existence and properties of diffuse interstellar bands (DIBs) outside the optical domain is still limited. Additional infra-red (IR) measurements and IR-optical correlative studies are needed to constrain DIB carriers and locate various absorbers in 3D maps of the interstellar matter. Methods: We extended our study of H-band DIBs in Apache Point Observatory Galactic Evolution Experiment (APOGEE) Telluric Standard Star (TSS) spectra. We used the strong λ15273 band to select the most and least absorbed targets. We used individual spectra of the former subsample to extract weaker DIBs, and we searched the two stacked series for differences that could indicate additional bands. High-resolution NARVAL and SOPHIE optical spectra for a subsample of 55 TSS targets were additionally recorded for NIR/optical correlative studies. Results: From the TSS spectra we extract a catalog of measurements of the poorly studied λλ15617, 15653, and 15673 DIBs in ≃300 sightlines, we obtain a first accurate determination of their rest wavelength and constrained their intrinsic width and shape. In addition, we studied the relationship between these weak bands and the strong λ15273 DIB. We provide a first or second confirmation of several other weak DIBs that have been proposed based on different instruments, and we add new constraints on their widths and locations. We finally propose two new DIB candidates. Conclusions: We compared the strength of the λ15273 absorptions with their optical counterparts λλ5780, 5797, 6196, 6283, and 6614. Using the 5797-5780 ratio as a tracer of shielding against the radiation field, we showed that the λ15273 DIB carrier is significantly more abundant in unshielded (σ-type) clouds, and it responds even more strongly than the λ5780 band carrier to the local ionizing field. Full Table 5 is available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/600/A129Based on SDSS/APOGEE Archive data, on observations collected with the NARVAL spectrograph on the Bernard Lyot telescope (TBL) at Observatoire du Pic du Midi (CNRS/UPS), France, and with the SOPHIE spectrograph on the Observatoire de Haute-Provence (OHP) 1.93 m telescope (CNRS/AMU).

Seedling growth responses to phosphorus reflect adult distribution patterns of tropical trees.

PubMed

Zalamea, Paul-Camilo; Turner, Benjamin L; Winter, Klaus; Jones, F Andrew; Sarmiento, Carolina; Dalling, James W

2016-10-01

Soils influence tropical forest composition at regional scales. In Panama, data on tree communities and underlying soils indicate that species frequently show distributional associations to soil phosphorus. To understand how these associations arise, we combined a pot experiment to measure seedling responses of 15 pioneer species to phosphorus addition with an analysis of the phylogenetic structure of phosphorus associations of the entire tree community. Growth responses of pioneers to phosphorus addition revealed a clear tradeoff: species from high-phosphorus sites grew fastest in the phosphorus-addition treatment, while species from low-phosphorus sites grew fastest in the low-phosphorus treatment. Traits associated with growth performance remain unclear: biomass allocation, phosphatase activity and phosphorus-use efficiency did not correlate with phosphorus associations; however, phosphatase activity was most strongly down-regulated in response to phosphorus addition in species from high-phosphorus sites. Phylogenetic analysis indicated that pioneers occur more frequently in clades where phosphorus associations are overdispersed as compared with the overall tree community, suggesting that selection on phosphorus acquisition and use may be strongest for pioneer species with high phosphorus demand. Our results show that phosphorus-dependent growth rates provide an additional explanation for the regional distribution of tree species in Panama, and possibly elsewhere. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Many faces of dogmatism: Prejudice as a way of protecting certainty against value violators among dogmatic believers and atheists.

PubMed

Kossowska, Małgorzata; Czernatowicz-Kukuczka, Aneta; Sekerdej, Maciej

2017-02-01

In this article, we suggest that dogmatic beliefs, manifested as strong beliefs that there is no God (i.e., dogmatic atheism) as well as strong beliefs in God (i.e., religious orthodoxy), can serve as a cognitive response to uncertainty. Moreover, we claim that people who dogmatically do not believe in religion and those who dogmatically believe in religion are equally prone to intolerance and prejudice towards groups that violate their important values. That is because prejudice towards these groups may be an efficient strategy to protect the certainty that strong beliefs provide. We tested these assumptions in two studies. In Study 1 and Study 2, we demonstrated that dogmatic beliefs mediate the relationship between intolerance to uncertainty and both, religious orthodoxy and dogmatic atheism. In addition, in Study 2 we showed that both the religiously orthodox and dogmatic atheists become prejudiced towards groups that violate their values and that these effects are especially strong under experimentally induced uncertainty. In this study, we focused on atheists and homosexuals as groups that pose a threat to Christian's religious worldviews, and Catholics and pro-life supporters as groups that pose a threat to the values of atheists. The results are discussed in relation to past research on dogmatism and religion, as well as with reference to what this means for the study of prejudice. © 2016 The British Psychological Society.

Self-Assembly of a Strong Polyhedral Oligomeric Silsesquioxane Core-Based Aspartate Derivative Dendrimer Supramolecular Gelator in Different Polarity Solvents.

PubMed

He, Huiwen; Chen, Si; Tong, Xiaoqian; An, Zhihang; Ma, Meng; Wang, Xiaosong; Wang, Xu

2017-11-21

Aromatic groups are introduced into the end peripherals of polyhedral oligomeric silsesquioxane (POSS) core-based organic/inorganic hybrid supramolecules to get a novel dendrimer gelator POSS-Z-Asp(OBzl) (POSS-ASP), which have eight aspartate derivative arms to make full use of strong π-π stacking forces to get strong supramolecular gels in addition to multiple hydrogen bindings and van der Waals interactions. POSS-ASP can self-assemble into three-dimensional nanoscale gel networks to provide hybrid physical gels especially with strong mechanical properties and fast-recovery behaviors. Two totally different morphologies of the connected spherical particle structures and banded ultralong fibers are observed owing to the polarity of solvents confirmed by the scanning electron microscopy, polarized optical microscopy, and transmission electron microscopy techniques, expecting the existing various self-assembly models and illustrating the peripherals of the dendrimer and the polarity of solvents having huge influences in the supramolecular self-assembly mechanism. What is more, the thermal stability, rheological properties, and network architecture information have also been investigated via tube-inversion, rotational rheometer, and powder X-ray diffraction methods, the results of which confirm the two different gel formation mechanisms that make POSS-ASP to exhibit two totally different thermal and mechanical properties. Such a study reports a new gelation system in organic or organic/aqueous mixed solvents, which can be helpful for investigating the relationship of dendritic supramolecular gelation and different polarity solvents during the supramolecular self-assembly process of gelators.

Force sensing by the vascular protein von Willebrand factor is tuned by a strong intermonomer interaction

PubMed Central

Müller, Jochen P.; Mielke, Salomé; Löf, Achim; Obser, Tobias; Beer, Christof; Bruetzel, Linda K.; Pippig, Diana A.; Vanderlinden, Willem; Lipfert, Jan; Schneppenheim, Reinhard; Benoit, Martin

2016-01-01

The large plasma glycoprotein von Willebrand factor (VWF) senses hydrodynamic forces in the bloodstream and responds to elevated forces with abrupt elongation, thereby increasing its adhesiveness to platelets and collagen. Remarkably, forces on VWF are elevated at sites of vascular injury, where VWF’s hemostatic potential is important to mediate platelet aggregation and to recruit platelets to the subendothelial layer. Adversely, elevated forces in stenosed vessels lead to an increased risk of VWF-mediated thrombosis. To dissect the remarkable force-sensing ability of VWF, we have performed atomic force microscopy (AFM)-based single-molecule force measurements on dimers, the smallest repeating subunits of VWF multimers. We have identified a strong intermonomer interaction that involves the D4 domain and critically depends on the presence of divalent ions, consistent with results from small-angle X-ray scattering (SAXS). Dissociation of this strong interaction occurred at forces above ∼50 pN and provided ∼80 nm of additional length to the elongation of dimers. Corroborated by the static conformation of VWF, visualized by AFM imaging, we estimate that in VWF multimers approximately one-half of the constituent dimers are firmly closed via the strong intermonomer interaction. As firmly closed dimers markedly shorten VWF’s effective length contributing to force sensing, they can be expected to tune VWF’s sensitivity to hydrodynamic flow in the blood and to thereby significantly affect VWF’s function in hemostasis and thrombosis. PMID:26787887

Carbohydrate recognition by the antiviral lectin cyanovirin-N

PubMed Central

Fujimoto, Yukiji K.; Green, David F.

2012-01-01

Cyanovirin-N is a cyanobacterial lectin with potent antiviral activity, and has been the focus of extensive pre-clinical investigation as a potential prophylactic for the prevention of the sexual transmission of the human immunodeficiency virus (HIV). Here we present a detailed analysis of carbohydrate recognition by this important protein, using a combination of computational methods, including extensive molecular dynamics simulations and Molecular-Mechanics/ Poisson–Boltzmann/Surface-Area (MM/PBSA) energetic analysis. The simulation results strongly suggest that the observed tendency of wildtype CVN to form domain-swapped dimers is the result of a previously unidentified cis-peptide bond present in the monomeric state. The energetic analysis additionally indicates that the highest-affinity ligand for CVN characterized to date (α-Man-(1,2)-α-Man-(1,2)-α-Man) is recognized asymmetrically by the two binding sites. Finally, we are able to provide a detailed map of the role of all binding site functional groups (both backbone and side chain) to various aspects of molecular recognition: general affinity for cognate ligands, specificity for distinct oligosaccharide targets and the asymmetric recognition of α-Man-(1,2)-α-Man-(1,2)-α-Man. Taken as a whole, these results complement past experimental characterization (both structural and thermodynamic) to provide the most complete understanding of carbohydrate recognition by CVN to date. The results also provide strong support for the application of similar approaches to the understanding of other protein–carbohydrate complexes. PMID:23057413

Passive shimming of the fringe field of a superconducting magnet for ultra-low field hyperpolarized noble gas MRI.

PubMed

Parra-Robles, Juan; Cross, Albert R; Santyr, Giles E

2005-05-01

Hyperpolarized noble gases (HNGs) provide exciting possibilities for MR imaging at ultra-low magnetic field strengths (<0.15 T) due to the extremely high polarizations available from optical pumping. The fringe field of many superconductive magnets used in clinical MR imaging can provide a stable magnetic field for this purpose. In addition to offering the benefit of HNG MR imaging alongside conventional high field proton MRI, this approach offers the other useful advantage of providing different field strengths at different distances from the magnet. However, the extremely strong field gradients associated with the fringe field present a major challenge for imaging since impractically high active shim currents would be required to achieve the necessary homogeneity. In this work, a simple passive shimming method based on the placement of a small number of ferromagnetic pieces is proposed to reduce the fringe field inhomogeneities to a level that can be corrected using standard active shims. The method explicitly takes into account the strong variations of the field over the volume of the ferromagnetic pieces used to shim. The method is used to obtain spectra in the fringe field of a high-field (1.89 T) superconducting magnet from hyperpolarized 129Xe gas samples at two different ultra-low field strengths (8.5 and 17 mT). The linewidths of spectra measured from imaging phantoms (30 Hz) indicate a homogeneity sufficient for MRI of the rat lung.

Towards an integrated European strong motion data distribution

NASA Astrophysics Data System (ADS)

Luzi, Lucia; Clinton, John; Cauzzi, Carlo; Puglia, Rodolfo; Michelini, Alberto; Van Eck, Torild; Sleeman, Reinhoud; Akkar, Sinan

2013-04-01

Recent decades have seen a significant increase in the quality and quantity of strong motion data collected in Europe, as dense and often real-time and continuously monitored broadband strong motion networks have been constructed in many nations. There has been a concurrent increase in demand for access to strong motion data not only from researchers for engineering and seismological studies, but also from civil authorities and seismic networks for the rapid assessment of ground motion and shaking intensity following significant earthquakes (e.g. ShakeMaps). Aside from a few notable exceptions on the national scale, databases providing access to strong motion data has not appeared to keep pace with these developments. In the framework of the EC infrastructure project NERA (2010 - 2014), that integrates key research infrastructures in Europe for monitoring earthquakes and assessing their hazard and risk, the network activity NA3 deals with the networking of acceleration networks and SM data. Within the NA3 activity two infrastructures are being constructed: i) a Rapid Response Strong Motion (RRSM) database, that following a strong event, automatically parameterises all available on-scale waveform data within the European Integrated waveform Data Archives (EIDA) and makes the waveforms easily available to the seismological community within minutes of an event; and ii) a European Strong Motion (ESM) database of accelerometric records, with associated metadata relevant to earthquake engineering and seismology research communities, using standard, manual processing that reflects the state of the art and research needs in these fields. These two separate repositories form the core infrastructures being built to distribute strong motion data in Europe in order to guarantee rapid and long-term availability of high quality waveform data to both the international scientific community and the hazard mitigation communities. These infrastructures will provide the access to strong motion data in an eventual EPOS seismological service. A working group on Strong Motion data is being created at ORFEUS in 2013. This body, consisting of experts in strong motion data collection, processing and research from across Europe, will provide the umbrella organisation that will 1) have the political clout to negotiate data sharing agreements with strong motion data providers and 2) manage the software during a transition from the end of NERA to the EPOS community. We expect the community providing data to the RRSM and ESM will gradually grow, under the supervision of ORFEUS, and eventually include strong motion data from networks from all European countries that can have an open data policy.

Metal mixture modeling evaluation project: 2. Comparison of four modeling approaches.

PubMed

Farley, Kevin J; Meyer, Joseph S; Balistrieri, Laurie S; De Schamphelaere, Karel A C; Iwasaki, Yuichi; Janssen, Colin R; Kamo, Masashi; Lofts, Stephen; Mebane, Christopher A; Naito, Wataru; Ryan, Adam C; Santore, Robert C; Tipping, Edward

2015-04-01

As part of the Metal Mixture Modeling Evaluation (MMME) project, models were developed by the National Institute of Advanced Industrial Science and Technology (Japan), the US Geological Survey (USA), HDR|HydroQual (USA), and the Centre for Ecology and Hydrology (United Kingdom) to address the effects of metal mixtures on biological responses of aquatic organisms. A comparison of the 4 models, as they were presented at the MMME workshop in Brussels, Belgium (May 2012), is provided in the present study. Overall, the models were found to be similar in structure (free ion activities computed by the Windermere humic aqueous model [WHAM]; specific or nonspecific binding of metals/cations in or on the organism; specification of metal potency factors or toxicity response functions to relate metal accumulation to biological response). Major differences in modeling approaches are attributed to various modeling assumptions (e.g., single vs multiple types of binding sites on the organism) and specific calibration strategies that affected the selection of model parameters. The models provided a reasonable description of additive (or nearly additive) toxicity for a number of individual toxicity test results. Less-than-additive toxicity was more difficult to describe with the available models. Because of limitations in the available datasets and the strong interrelationships among the model parameters (binding constants, potency factors, toxicity response parameters), further evaluation of specific model assumptions and calibration strategies is needed. © 2014 SETAC.

Metal Mixture Modeling Evaluation project: 2. Comparison of four modeling approaches

USGS Publications Warehouse

Farley, Kevin J.; Meyer, Joe; Balistrieri, Laurie S.; DeSchamphelaere, Karl; Iwasaki, Yuichi; Janssen, Colin; Kamo, Masashi; Lofts, Steve; Mebane, Christopher A.; Naito, Wataru; Ryan, Adam C.; Santore, Robert C.; Tipping, Edward

2015-01-01

As part of the Metal Mixture Modeling Evaluation (MMME) project, models were developed by the National Institute of Advanced Industrial Science and Technology (Japan), the U.S. Geological Survey (USA), HDR⎪HydroQual, Inc. (USA), and the Centre for Ecology and Hydrology (UK) to address the effects of metal mixtures on biological responses of aquatic organisms. A comparison of the 4 models, as they were presented at the MMME Workshop in Brussels, Belgium (May 2012), is provided herein. Overall, the models were found to be similar in structure (free ion activities computed by WHAM; specific or non-specific binding of metals/cations in or on the organism; specification of metal potency factors and/or toxicity response functions to relate metal accumulation to biological response). Major differences in modeling approaches are attributed to various modeling assumptions (e.g., single versus multiple types of binding site on the organism) and specific calibration strategies that affected the selection of model parameters. The models provided a reasonable description of additive (or nearly additive) toxicity for a number of individual toxicity test results. Less-than-additive toxicity was more difficult to describe with the available models. Because of limitations in the available datasets and the strong inter-relationships among the model parameters (log KM values, potency factors, toxicity response parameters), further evaluation of specific model assumptions and calibration strategies is needed.

Phonon Scattering in Thermoelectrics: Thermal Transport, Strong Anharmonicity, and Emergent Quasiparticles

NASA Astrophysics Data System (ADS)

Delaire, Olivier

Modern neutron and x-ray spectrometers can map phonon dispersions and scattering rates throughout reciprocal space, providing unique insights into microscopic scattering mechanisms, including anharmonicity, electron-phonon coupling, or scattering by defects and nanostructures. In addition, first-principles simulations enable the rationalization of extensive experimental datasets. In particular, ab-initio molecular dynamics simulations can capture striking effects of anharmonicity near lattice instabilities. A number of high-performance thermoelectric materials are found in the vicinity of lattice instabilities, including Pb chalcogenides PbX, SnSe, Cu2Se, among others. The large phonon anharmonicity found in such compounds suppresses the lattice thermal conductivity, enhancing their thermoelectric efficiency. In this presentation, I will present results from our investigations of phonons in these materials using neutron and x-ray scattering combined with first-principles simulations, focusing on anharmonic effects near lattice instabilities. I will show how strong anharmonicity can lead to emergent quasiparticles qualitatively different from harmonic phonons, which we probe in our measurements and simulations of the phonon self-energy. Commonalities between systems will be highlighted, including connections between strong anharmonicity and the electronic structure. Funding from US DOE, Office of Basic Energy Sciences, Materials Science and Engineering Division, Office of Science Early Career program (DE-SC0016166), and as part of the S3TEC EFRC (DE-SC0001299).

Experiment-theory comparison for low frequency BAE modes in the strongly shaped H-1NF stellarator

DOE PAGES

Haskey, S. R.; Blackwell, B. D.; Nuhrenberg, C.; ...

2015-08-12

Here, recent advances in the modeling, analysis, and measurement of fluctuations have significantly improved the diagnosis and understanding of Alfvén eigenmodes in the strongly shaped H-1NF helical axis stellarator. Experimental measurements, including 3D tomographic inversions of high resolution visible light images, are in close agreement with beta-induced Alfvén eigenmodes (BAEs) calculated using the compressible ideal MHD code, CAS3D. This is despite the low β in H-1NF, providing experimental evidence that these modes can exist due to compression that is induced by the strong shaping in stellarators, in addition to high β, as is the case in tokamaks. This is confirmedmore » using the CONTI and CAS3D codes, which show significant gap structures at lower frequencies which contain BAE and beta-acoustic Alfvén eigenmodes (BAAEs). The BAEs are excited in the absence of a well confined energetic particle source, further confirming previous studies that thermal particles, electrons, or even radiation fluctuations can drive these modes. Datamining of magnetic probe data shows the experimentally measured frequency of these modes has a clear dependence on the rotational transform profile, which is consistent with a frequency dependency due to postulated confinement related temperature variations.« less

Le(x) glycan mediates homotypic adhesion of embryonal cells independently from E-cadherin: a preliminary note.

PubMed

Handa, Kazuko; Takatani-Nakase, Tomoka; Larue, Lionel; Stemmler, Marc P; Kemler, Rolf; Hakomori, Sen-itiroh

2007-06-22

Le(x) glycan and E-cadherin (Ecad) are co-expressed at embryonal stem (ES) cells and embryonal carcinoma (EC) cells. While the structure and function of Ecad mediating homotypic adhesion of these cells have been well established, evidence that Le(x) glycan also mediates such adhesion is weak, despite the fact that Le(x) oligosaccharide inhibits the compaction process. To provide stronger evidence, we knocked out Ecad gene in EC and ES cells to establish F9 Ecad (-/-) and D3M Ecad (-/-) cells, which highly express Le(x) glycan but do not express Ecad at all. Both F9 Ecad (-/-) and D3M Ecad (-/-) cells displayed strong autoaggregation in the presence of Ca(2+), while PYS-2 cells, which express trace amount of Ecad and undetectable level of Le(x) glycan, did not display autoaggregation. In addition, F9 Ecad (-/-) and D3M Ecad (-/-) cells displayed strong adhesion to plates coated with Le(x) glycosphingolipid (III(3)FucnLc4Cer), in dose-dependent manner, in the presence of Ca(2+). Thus, ES or EC cells display autoaggregation and strong adhesion to Le(x)-coated plates in the absence of Ecad, further supporting the notion of Le(x) self-recognition (i.e., Le(x)-to-Le(x) interaction) in cell adhesion.

Construct Validity of the MMPI-2-RF Triarchic Psychopathy Scales in Correctional and Collegiate Samples.

PubMed

Kutchen, Taylor J; Wygant, Dustin B; Tylicki, Jessica L; Dieter, Amy M; Veltri, Carlo O C; Sellbom, Martin

2017-01-01

This study examined the MMPI-2-RF (Ben-Porath & Tellegen, 2008/2011) Triarchic Psychopathy scales recently developed by Sellbom et al. ( 2016 ) in 3 separate groups of male correctional inmates and 2 college samples. Participants were administered a diverse battery of psychopathy specific measures (e.g., Psychopathy Checklist-Revised [Hare, 2003 ], Psychopathic Personality Inventory-Revised [Lilienfeld & Widows, 2005 ], Triarchic Psychopathy Measure [Patrick, 2010 ]), omnibus personality and psychopathology measures such as the Personality Assessment Inventory (Morey, 2007 ) and Personality Inventory for DSM-5 (Krueger, Derringer, Markon, Watson, & Skodol, 2012 ), and narrow-band measures that capture conceptually relevant constructs. Our results generally evidenced strong support for the convergent and discriminant validity for the MMPI-2-RF Triarchic scales. Boldness was largely associated with measures of fearless dominance, social potency, and stress immunity. Meanness showed strong relationships with measures of callousness, aggression, externalizing tendencies, and poor interpersonal functioning. Disinhibition exhibited strong associations with poor impulse control, stimulus seeking, and general externalizing proclivities. Our results provide additional construct validation to both the triarchic model and MMPI-2-RF Triarchic scales. Given the widespread use of the MMPI-2-RF in correctional and forensic settings, our results have important implications for clinical assessment in these 2 areas, where psychopathy is a highly relevant construct.

First instalment in resolution of the Banksia spinulosa complex (Proteaceae): B. neoanglica, a new species supported by phenetic analysis, ecology and geography

PubMed Central

Stimpson, Margaret L.; Weston, Peter H.; Telford, Ian R.H.; Bruhl, Jeremy J.

2012-01-01

Abstract Taxa in the Banksia spinulosa Sm. complex (Proteaceae) have populations with sympatric, parapatric and allopatric distributions and unclear or disputed boundaries. Our hypothesis is that under biological, phenetic and diagnosable species concepts that each of the currently named taxa within the Banksia spinulosa complex is a separate species. Based on specimens collected as part of this study, and data recorded from specimens in six Australian herbaria, complemented by phenetic analysis (semi–strong multidimensional scaling and UPGMA clustering) and a detailed morphological study, we investigated both morphological variation and geographic distribution in the Banksia spinulosa complex. All specimens used for this study are held at the N.C.W. Beadle Herbarium or the National Herbarium of New South Wales. In total 23 morphological characters (11 quantitative, five binary, and seven multistate characters) were analysed phenetically for 89 specimens. Ordination and cluster analysis resulted in individuals grouping strongly allowing recognition of distinct groups consistent with their recognition as separate species. Additional morphological analysis was completed on all specimens using leaf, floral, fruit and stem morphology, providing clear cut diagnosable groups and strong support for the recognition of Banksia spinulosa var. cunninghamii and Banksia spinulosa var. neoanglica as species. PMID:23170073

Web-based objective structured clinical examination with remote standardized patients and Skype: resident experience.

PubMed

Langenau, Erik; Kachur, Elizabeth; Horber, Dot

2014-07-01

Using Skype and remote standardized patients (RSPs), investigators sought to evaluate user acceptance of a web-based objective structured clinical examination (OSCE) among resident physicians. After participating in four web-based clinical encounters addressing pain with RSPs, 59 residents from different training programs, disciplines and geographic locations completed a 52-item questionnaire regarding their experience with Skype and RSPs. Open-ended responses were solicited as well. The majority of participants (97%) agreed or strongly agreed the web-based format was convenient and a practical learning exercise, and 90% agreed or strongly agreed the format was effective in teaching communication skills. Although 93% agreed or strongly agreed they could communicate easily with RSPs using Skype, 80% preferred traditional face-to-face clinical encounters, and 58% reported technical difficulties during the encounters. Open-ended written responses supported survey results. Findings from this study expose challenges with technology and human factors, but positive experiences support the continued investigation of web-based OSCEs as a synchronous e-learning initiative for teaching and assessing doctor-patient communication. Such educational programs are valuable but unlikely to replace face-to-face encounters with patients. This web-based OSCE program provides physician learners with additional opportunity to improve doctor-patient communication. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Bilayer synergetic coupling double negative acoustic metasurface and cloak.

PubMed

Ma, Fuyin; Huang, Meng; Xu, Yicai; Wu, Jiu Hui

2018-04-12

In this paper, we propose a bilayer plate-type lightweight double negative metasurface based on a new synergetic coupling design concept, by which the perfect absorption, double negative bands, free manipulation of phase shifts with a 2π span and acoustic cloak can be successively realized. Firstly, the synergetic behavior between resonant and anti-resonant plates is presented to construct a bilayer unit in which each component respectively provides a pre-defined function in realizing the perfect absorption. Based on this bilayer structure, a double negative band with simultaneously negative effective mass density and bulk modulus is obtained, which, as a metasurface, can obtain continuous phase shifts almost completely covering a 2π range, thus facilitating the design of a three-dimensional (3D) acoustic cloak. In addition, based on this strong sound absorption concept, a two-dimensional (2D) omnidirectional broadband acoustical dark skin, covering between 800 to 6000 Hz, is also demonstrated through the proposed bilayer plate-type structure form. The proposed design concepts and metasurfaces have widespread potential application values in strong sound attenuation, filtering, superlens, imaging, cloak, and extraordinary wave steering, in which the attributes of strong absorption, double negative parameters or continuous phase shifts with full 2π span are required to realize the expected extraordinary physical features.

Spatial complexity reduces interaction strengths in the meta-food web of a river floodplain mosaic

USGS Publications Warehouse

Bellmore, James Ryan; Baxter, Colden Vance; Connolly, Patrick J.

2015-01-01

Theory states that both the spatial complexity of landscapes and the strength of interactions between consumers and their resources are important for maintaining biodiversity and the 'balance of nature.' Spatial complexity is hypothesized to promote biodiversity by reducing potential for competitive exclusion; whereas, models show weak trophic interactions can enhance stability and maintain biodiversity by dampening destabilizing oscillations associated with strong interactions. Here we show that spatial complexity can reduce the strength of consumer-resource interactions in natural food webs. By sequentially aggregating food webs of individual aquatic habitat patches across a floodplain mosaic, we found that increasing spatial complexity resulted in decreases in the strength of interactions between predators and prey, owing to a greater proportion of weak interactions and a reduced proportion of strong interactions in the meta-food web. The main mechanism behind this pattern was that some patches provided predation refugia for species which were often strongly preyed upon in other patches. If weak trophic interactions do indeed promote stability, then our findings may signal an additional mechanism by which complexity and stability are linked in nature. In turn, this may have implications for how the values of landscape complexity, and the costs of biophysical homogenization, are assessed.

Acute effects of air pollution on respiratory disease mortalities and outpatients in Southeastern China.

PubMed

Mo, Zhe; Fu, Qiuli; Zhang, Lifang; Lyu, Danni; Mao, Guangming; Wu, Lizhi; Xu, Peiwei; Wang, Zhifang; Pan, Xuejiao; Chen, Zhijian; Wang, Xiaofeng; Lou, Xiaoming

2018-02-22

The objective of this study was to investigate the potential association between air pollutants and respiratory diseases (RDs). Generalized additive models were used to analyze the effect of air pollutants on mortalities or outpatient visits. The average concentrations of air pollutants in Hangzhou (HZ) were 1.6-2.8 times higher than those in Zhoushan (ZS), except for O 3 . In a single pollutant model, the increased concentrations of PM 2.5 , NO 2 , and SO 2 were strongly associated with deaths caused by RD in HZ, while PM 2.5 and O 3 were associated with deaths caused by RD in ZS. All air pollutants (PM 2.5 , NO 2 , SO 2 , and O 3 ) were strongly associated with outpatient visits for RD in both HZ and ZS. In multiple pollutant models, a significant association was only observed between PM 2.5 and the mortality rate of RD patients in both HZ and in ZS. Moreover, strong associations between SO 2 , NO 2 , and outpatient visits for RD were observed in HZ and ZS. This study has provided evidence that both the mortality rates and outpatient visits for RD were significantly associated with air pollutants. Furthermore, the results showed that different air pollutant levels lead to regional differences between mortality rates and outpatient visits.

Interaction of strong converging shock wave with SF6 gas bubble

NASA Astrophysics Data System (ADS)

Liang, Yu; Zhai, ZhiGang; Luo, XiSheng

2018-06-01

Interaction of a strong converging shock wave with an SF6 gas bubble is studied, focusing on the effects of shock intensity and shock shape on interface evolution. Experimentally, the converging shock wave is generated by shock dynamics theory and the gas bubble is created by soap film technique. The post-shock flow field is captured by a schlieren photography combined with a high-speed video camera. Besides, a three-dimensional program is adopted to provide more details of flow field. After the strong converging shock wave impact, a wide and pronged outward jet, which differs from that in planar shock or weak converging shock condition, is derived from the downstream interface pole. This specific phenomenon is considered to be closely associated with shock intensity and shock curvature. Disturbed by the gas bubble, the converging shocks approaching the convergence center have polygonal shapes, and the relationship between shock intensity and shock radius verifies the applicability of polygonal converging shock theory. Subsequently, the motion of upstream point is discussed, and a modified nonlinear theory considering rarefaction wave and high amplitude effects is proposed. In addition, the effects of shock shape on interface morphology and interface scales are elucidated. These results indicate that the shape as well as shock strength plays an important role in interface evolution.

Understanding lattice thermal conductivity in thermoelectric clathrates: A density functional theory study on binary Si-based type-I clathrates

NASA Astrophysics Data System (ADS)

Euchner, Holger; Pailhès, Stéphane; Giordano, Valentina M.; de Boissieu, Marc

2018-01-01

Despite their crystalline nature, thermoelectric clathrates exhibit a strongly reduced lattice thermal conductivity. While the reason for this unexpected behavior is known to lie in the peculiarities of the complex crystal structure and the interplay of the underlying guest-host framework, their respective roles are still not fully disentangled and understood. Our ab initio study of the most simple type-I clathrate phase, the binary compound Ba8Si46 and its derivatives Ba8 -xSi46 seeks to identify these mechanisms and provides insight into their origin. Indeed, the strongly decreased lattice thermal conductivity in thermoelectric clathrates is a consequence of a reduction of the acoustic phonon bandwidth, a lowering of the acoustic phonon group velocities, and the amplification of three-phonon-scattering processes. While the complexity of the crystal structure is demonstrated not to be the leading factor, the reasons are manifold. A modified Si-Si interaction causes a first decrease of the sound velocity, whereas the presence of flat Ba modes results in an additional lowering. These modes correspond to confined Bloch states that are localized on the Ba atoms and significantly increase the scattering phase space and, together with an increased anharmonicity of the interatomic interactions, strongly affect the phonon lifetimes.

Digital Libraries: The Next Generation in File System Technology.

ERIC Educational Resources Information Center

Bowman, Mic; Camargo, Bill

1998-01-01

Examines file sharing within corporations that use wide-area, distributed file systems. Applications and user interactions strongly suggest that the addition of services typically associated with digital libraries (content-based file location, strongly typed objects, representation of complex relationships between documents, and extrinsic…

Strong CP and SUZ2

NASA Astrophysics Data System (ADS)

Albaid, Abdelhamid; Dine, Michael; Draper, Patrick

2015-12-01

Solutions to the strong CP problem typically introduce new scales associated with the spontaneous breaking of symmetries. Absent any anthropic argument for small overline{θ} , these scales require stabilization against ultraviolet corrections. Supersymmetry offers a tempting stabilization mechanism, since it can solve the "big" electroweak hierarchy problem at the same time. One family of solutions to strong CP, including generalized parity models, heavy axion models, and heavy η' models, introduces {Z}_2 copies of (part of) the Standard Model and an associated scale of {Z}_2 -breaking. We review why, without additional structure such as supersymmetry, the {Z}_2 -breaking scale is unacceptably tuned. We then study "SUZ2" models, supersymmetric theories with {Z}_2 copies of the MSSM. We find that the addition of SUSY typically destroys the {Z}_2 protection of overline{θ}=0 , even at tree level, once SUSY and {Z}_2 are broken. In theories like supersymmetric completions of the twin Higgs, where {Z}_2 addresses the little hierarchy problem but not strong CP, two axions can be used to relax overline{θ}.

A statistical approach for evaluating the effectiveness of heartworm preventive drugs: what does 100% efficacy really mean?

PubMed

Vidyashankar, Anand N; Jimenez Castro, Pablo D; Kaplan, Ray M

2017-11-09

Initial studies of heartworm preventive drugs all yielded an observed efficacy of 100% with a single dose, and based on these data the US Food and Drug Administration (FDA) required all products to meet this standard for approval. Those initial studies, however, were based on just a few strains of parasites, and therefore were not representative of the full assortment of circulating biotypes. This issue has come to light in recent years, where it has become common for studies to yield less than 100% efficacy. This has changed the landscape for the testing of new products because heartworm efficacy studies lack the statistical power to conclude that finding zero worms is different from finding a few worms. To address this issue, we developed a novel statistical model, based on a hierarchical modeling and parametric bootstrap approach that provides new insights to assess multiple sources of variability encountered in heartworm drug efficacy studies. Using the newly established metrics we performed both data simulations and analyzed actual experimental data. Our results suggest that an important source of modeling variability arises from variability in the parasite establishment rate between dogs; not accounting for this can overestimate the efficacy in more than 40% of cases. We provide strong evidence that ZoeMo-2012 and JYD-34, which both were established from the same source dog, have differing levels of susceptibility to moxidectin. In addition, we provide strong evidence that the differences in efficacy seen in two published studies using the MP3 strain were not due to randomness, and thus must be biological in nature. Our results demonstrate how statistical modeling can improve the interpretation of data from heartworm efficacy studies by providing a means to identify the true efficacy range based on the observed data. Importantly, these new insights should help to inform regulators on how to move forward in establishing new statistically and scientifically valid requirements for efficacy in the registration of new heartworm preventative products. Furthermore, our results provide strong evidence that heartworm 'strains' can change their susceptibility phenotype over short periods of time, providing further evidence that a wide diversity of susceptibility phenotypes exists among naturally circulating biotypes of D. immitis.

Update on the Center for Engineering Strong Motion Data

NASA Astrophysics Data System (ADS)

Haddadi, H. R.; Shakal, A. F.; Stephens, C. D.; Oppenheimer, D. H.; Huang, M.; Leith, W. S.; Parrish, J. G.; Savage, W. U.

2010-12-01

The U.S. Geological Survey (USGS) and the California Geological Survey (CGS) established the Center for Engineering Strong-Motion Data (CESMD, Center) to provide a single access point for earthquake strong-motion records and station metadata from the U.S. and international strong-motion programs. The Center has operational facilities in Sacramento and Menlo Park, California, to receive, process, and disseminate records through the CESMD web site at www.strongmotioncenter.org. The Center currently is in the process of transitioning the COSMOS Virtual Data Center (VDC) to integrate its functions with those of the CESMD for improved efficiency of operations, and to provide all users with a more convenient one-stop portal to both U.S. and important international strong-motion records. The Center is working with COSMOS and international and U.S. data providers to improve the completeness of site and station information, which are needed to most effectively employ the recorded data. The goal of all these and other new developments is to continually improve access by the earthquake engineering community to strong-motion data and metadata world-wide. The CESMD and its Virtual Data Center (VDC) provide tools to map earthquakes and recording stations, to search raw and processed data, to view time histories and spectral plots, to convert data files formats, and to download data and a variety of information. The VDC is now being upgraded to convert the strong-motion data files from different seismic networks into a common standard tagged format in order to facilitate importing earthquake records and station metadata to the CESMD database. An important new feature being developed is the automatic posting of Internet Quick Reports at the CESMD web site. This feature will allow users, and emergency responders in particular, to view strong-motion waveforms and download records within a few minutes after an earthquake occurs. Currently the CESMD and its Virtual Data Center provide selected strong-motion records from 17 countries. The Center has proved to be significantly useful for providing data to scientists, engineers, policy makers, and emergency response teams around the world.

Highly porous and mechanically strong ceramic oxide aerogels

NASA Technical Reports Server (NTRS)

Johnston, James C. (Inventor); Leventis, Nicholas (Inventor); Ilhan, Ulvi F. (Inventor); Meador, Mary Ann B. (Inventor); Fabrizio, Eve F. (Inventor)

2012-01-01

Structurally stable and mechanically strong ceramic oxide aerogels are provided. The aerogels are cross-linked via organic polymer chains that are attached to and extend from surface-bound functional groups provided or present over the internal surfaces of a mesoporous ceramic oxide particle network via appropriate chemical reactions. The functional groups can be hydroxyl groups, which are native to ceramic oxides, or they can be non-hydroxyl functional groups that can be decorated over the internal surfaces of the ceramic oxide network. Methods of preparing such mechanically strong ceramic oxide aerogels also are provided.

Highly porous and mechanically strong ceramic oxide aerogels

NASA Technical Reports Server (NTRS)

Fabrizio, Eve F. (Inventor); Leventis, Nicholas (Inventor); Ilhan, Ulvi F. (Inventor); Meador, Mary Ann B. (Inventor); Johnston, James C. (Inventor)

2010-01-01

Structurally stable and mechanically strong ceramic oxide aerogels are provided. The aerogels are cross-linked via organic polymer chains that are attached to and extend from surface-bound functional groups provided or present over the internal surfaces of a mesoporous ceramic oxide particle network via appropriate chemical reactions. The functional groups can be hydroxyl groups, which are native to ceramic oxides, or they can be non-hydroxyl functional groups that can be decorated over the internal surfaces of the ceramic oxide network. Methods of preparing such mechanically strong ceramic oxide aerogels also are provided.

Quasicrystal-reinforced Mg alloys.

PubMed

Kyun Kim, Young; Tae Kim, Won; Hyang Kim, Do

2014-04-01

The formation of the icosahedral phase (I-phase) as a secondary solidification phase in Mg-Zn-Y and Mg-Zn-Al base systems provides useful advantages in designing high performance wrought magnesium alloys. The strengthening in two-phase composites (I-phase + α -Mg) can be explained by dispersion hardening due to the presence of I-phase particles and by the strong bonding property at the I-phase/matrix interface. The presence of an additional secondary solidification phase can further enhance formability and mechanical properties. In Mg-Zn-Y alloys, the co-presence of I and Ca 2 Mg 6 Zn 3 phases by addition of Ca can significantly enhance formability, while in Mg-Zn-Al alloys, the co-presence of the I-phase and Mg 2 Sn phase leads to the enhancement of mechanical properties. Dynamic and static recrystallization are significantly accelerated by addition of Ca in Mg-Zn-Y alloy, resulting in much smaller grain size and more random texture. The high strength of Mg-Zn-Al-Sn alloys is attributed to the presence of finely distributed Mg 2 Sn and I-phase particles embedded in the α -Mg matrix.

Quasicrystal-reinforced Mg alloys

PubMed Central

Kyun Kim, Young; Tae Kim, Won; Hyang Kim, Do

2014-01-01

The formation of the icosahedral phase (I-phase) as a secondary solidification phase in Mg–Zn–Y and Mg–Zn–Al base systems provides useful advantages in designing high performance wrought magnesium alloys. The strengthening in two-phase composites (I-phase + α-Mg) can be explained by dispersion hardening due to the presence of I-phase particles and by the strong bonding property at the I-phase/matrix interface. The presence of an additional secondary solidification phase can further enhance formability and mechanical properties. In Mg–Zn–Y alloys, the co-presence of I and Ca2Mg6Zn3 phases by addition of Ca can significantly enhance formability, while in Mg–Zn–Al alloys, the co-presence of the I-phase and Mg2Sn phase leads to the enhancement of mechanical properties. Dynamic and static recrystallization are significantly accelerated by addition of Ca in Mg–Zn–Y alloy, resulting in much smaller grain size and more random texture. The high strength of Mg–Zn–Al–Sn alloys is attributed to the presence of finely distributed Mg2Sn and I-phase particles embedded in the α-Mg matrix. PMID:27877660

Ammonium Additives to Dissolve Lithium Sulfide through Hydrogen Binding for High-Energy Lithium-Sulfur Batteries.

PubMed

Pan, Huilin; Han, Kee Sung; Vijayakumar, M; Xiao, Jie; Cao, Ruiguo; Chen, Junzheng; Zhang, Jiguang; Mueller, Karl T; Shao, Yuyan; Liu, Jun

2017-02-08

In rechargeable Li-S batteries, the uncontrollable passivation of electrodes by highly insulating Li 2 S limits sulfur utilization, increases polarization, and decreases cycling stability. Dissolving Li 2 S in organic electrolyte is a facile solution to maintain the active reaction interface between electrolyte and sulfur cathode, and thus address the above issues. Herein, ammonium salts are demonstrated as effective additives to promote the dissolution of Li 2 S to 1.25 M in DMSO solvent at room temperature. NMR measurements show that the strong hydrogen binding effect of N-H groups plays a critical role in dissolving Li 2 S by forming complex ligands with S 2- anions coupled with the solvent's solvating surrounding. Ammonium additives in electrolyte can also significantly improve the oxidation kinetics of Li 2 S, and therefore enable the direct use of Li 2 S as cathode material in Li-S battery system in the future. This provides a new approach to manage the solubility of lithium sulfides through cation coordination with sulfide anion.

Bis(pinacolato)diboron as an additive for the detection of thermal neutrons in plastic scintillators

NASA Astrophysics Data System (ADS)

Mahl, Adam; Yemam, Henok A.; Stuntz, John; Remedes, Tyler; Sellinger, Alan; Greife, Uwe

2016-04-01

A readily available and inexpensive boron compound was tested as an additive for the detection of thermal neutrons in plastic scintillators. Bis(pinacolato)diboron (B2Pin2) was determined to be a compatible boron source (8.51 wt% boron, 1.70 wt% 10B) in poly(vinyltoluene) based matrices. Plastic scintillator blends of 1-20 wt% 2,5-diphenyloxazole (PPO), 0.1 wt% 1,4-bis(5-phenyloxazol-2-yl) benzene (POPOP) and 1-15 wt% B2Pin2 were prepared that provided optical clarity, good mechanical properties, and the capability of thermal neutron detection. Independent of B2Pin2 concentration, strong 10B neutron capture signals around 90 keVee were observed at essentially constant light output. Increasing PPO concentration allowed for the use of pulse shape discrimination (PSD) in both fast and thermal neutron detection. High PPO concentrations appear to cause additional alpha quenching that affected the 10B neutron capture signal. Aging effects after storage in air for several months were observed, which led to degradation of performance and in some samples of mechanical stability.

Ammonium Additives to Dissolve Lithium Sulfide through Hydrogen Binding for High-Energy Lithium–Sulfur Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Huilin; Han, Kee Sung; Vijayakumar, M.

In rechargeable Li-S batteries, the uncontrollable passivation of electrodes by highly insulating Li2S limits sulfur utilization, increases polarization and decreases cycling stability. Dissolving Li2S in organic electrolyte is a facile solution to maintain the active reaction interface between electrolyte and sulfur cathode, and thus address the above issues. Herein, ammonium salts are demonstrated as effective additives to promote the dissolution of Li2S to 1.25 M in DMSO solvent at room temperature. NMR measurements show that the strong hydrogen binding effect of N-H groups plays a critical role in dissolving Li2S by forming complex ligands with S2- anions coupled with themore » solvent’s solvating surrounding. Ammonium additives in electrolyte can also significantly improve the oxidation kinetics of Li2S, therefore enables the direct use of Li2S as cathode material in Li-S battery system in the future. This provides a new approach to manage the solubility of lithium sulfides through cation coordination with sulfide anion.« less

Acceleration of Intended Pozzolanic Reaction under Initial Thermal Treatment for Developing Cementless Fly Ash Based Mortar.

PubMed

Kwon, Yang-Hee; Kang, Sung-Hoon; Hong, Sung-Gul; Moon, Juhyuk

2017-02-24

Without using strong alkaline solution or ordinary Portland cement, a new structural binder consisting of fly ash and hydrated lime was hardened through an intensified pozzolanic reaction. The main experimental variables are the addition of silica fume and initial thermal treatment (60 °C for 3 days). A series of experiments consisting of mechanical testing (compressive and flexural strength, modulus of elasticity), X-ray diffraction, and measurements of the heat of hydration, pore structure, and shrinkage were conducted. These tests show that this new fly ash-based mortar has a compressive strength of 15 MPa at 91 days without any silica fume addition or initial thermal treatment. The strength increased to over 50 MPa based on the acceleration of the intensified pozzolanic reaction from the silica fume addition and initial thermal treatment. This is explained by a significant synergistic effect induced by the silica fume. It intensifies the pozzolanic reaction under thermal treatment and provides a space filling effect. This improved material performance can open a new pathway to utilize the industrial by-product of fly ash in cementless construction materials.

Prevention of strong earthquakes: Goal or utopia?

NASA Astrophysics Data System (ADS)

Mukhamediev, Sh. A.

2010-11-01

In the present paper, we consider ideas suggesting various kinds of industrial impact on the close-to-failure block of the Earth’s crust in order to break a pending strong earthquake (PSE) into a number of smaller quakes or aseismic slips. Among the published proposals on the prevention of a forthcoming strong earthquake, methods based on water injection and vibro influence merit greater attention as they are based on field observations and the results of laboratory tests. In spite of this, the cited proofs are, for various reasons, insufficient to acknowledge the proposed techniques as highly substantiated; in addition, the physical essence of these methods has still not been fully understood. First, the key concept of the methods, namely, the release of the accumulated stresses (or excessive elastic energy) in the source region of a forthcoming strong earthquake, is open to objection. If we treat an earthquake as a phenomenon of a loss in stability, then, the heterogeneities of the physicomechanical properties and stresses along the existing fault or its future trajectory, rather than the absolute values of stresses, play the most important role. In the present paper, this statement is illustrated by the classical examples of stable and unstable fractures and by the examples of the calculated stress fields, which were realized in the source regions of the tsunamigenic earthquakes of December 26, 2004 near the Sumatra Island and of September 29, 2009 near the Samoa Island. Here, just before the earthquakes, there were no excessive stresses in the source regions. Quite the opposite, the maximum shear stresses τmax were close to their minimum value, compared to τmax in the adjacent territory. In the present paper, we provide quantitative examples that falsify the theory of the prevention of PSE in its current form. It is shown that the measures for the prevention of PSE, even when successful for an already existing fault, can trigger or accelerate a catastrophic earthquake because of dynamic fault propagation in the intact region. Some additional aspects of prevention of PSE are discussed. We conclude that in the near future, it is too early to consider the problem of prevention of a forthcoming strong earthquake as a practical task; otherwise, the results can prove to be very different from the desired ones. Nevertheless, it makes sense to continue studying this problem. The theoretical research and experimental investigation of the structure and properties of the regions where the prevention of a forthcoming strong earthquake is planned in the future are of primary importance.

Preserving enzymatic activity and enhancing biochemical stability of glutathione transferase by soluble additives under free and tethered conditions.

PubMed

Karamitros, Christos S; Labrou, Nikolaos E

2017-09-01

In the present study, we report the effect of four different soluble additives (sucrose, lactitol, superfloc c577, and dextran sulfate) on the stability of glutathione transferase 1 enzyme from Zea mays (ZmGSTF1-1) under free and tethered conditions at 4 and 25 °C. Among all additives, the best stabilizing effects were observed in the case of superfloc c577 and sucrose at both tested temperatures, yet at distinct concentrations at each condition. Those two stabilizing agents were further combined and potential positive synergistic effects were investigated. In addition, we assessed the long-term storage and operational stability of ZmGSTF1-1 under tethered conditions in the presence of additives, which provided the most conducive effects on its stability under free conditions. Our results strongly suggest that the presence of additives may be beneficial to the stability of the enzyme under both free and tethered conditions. Thermodynamic analysis of the free enzyme in the presence of sucrose, which exhibited the best stabilizing effect at both temperatures, shed light on the possible mechanism of action. Given the considerable importance of the development of GST-based biosensors with prolonged stability, the present work may be of general interest to researchers in the field of applied enzymology. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

Stabilizing Effects of Bacterial Biofilms: EPS Penetration and Redistribution of Bed Stability Down the Sediment Profile

NASA Astrophysics Data System (ADS)

Chen, X. D.; Zhang, C. K.; Zhou, Z.; Gong, Z.; Zhou, J. J.; Tao, J. F.; Paterson, D. M.; Feng, Q.

2017-12-01

Biofilms, consisting of microorganisms and their secreted extracellular polymeric substances (EPSs), serve as "ecosystem engineers" stabilizing sedimentary environments. Natural sediment bed provides an excellent substratum for biofilm growth. The porous structure and rich nutrients allow the EPS matrix to spread deeper into the bed. A series of laboratory-controlled experiments were conducted to investigate sediment colonization of Bacillus subtilis and the penetration of EPS into the sediment bed with incubation time. In addition to EPS accumulation on the bed surface, EPS also penetrated downward. However, EPS distribution developed strong vertical heterogeneity with a much higher content in the surface layer than in the bottom layer. Scanning electron microscope images of vertical layers also displayed different micromorphological properties of sediment-EPS matrix. In addition, colloidal and bound EPSs exhibited distinctive distribution patterns. After the full incubation, the biosedimentary beds were eroded to test the variation of bed stability induced by biological effects. This research provides an important reference for the prediction of sediment transport and hence deepens the understanding of the biologically mediated sediment system and broadens the scope of the burgeoning research field of "biomorphodynamics."

The ALI-ARMS Code for Modeling Atmospheric non-LTE Molecular Band Emissions: Current Status and Applications

NASA Technical Reports Server (NTRS)

Kutepov, A. A.; Feofilov, A. G.; Manuilova, R. O.; Yankovsky, V. A.; Rezac, L.; Pesnell, W. D.; Goldberg, R. A.

2008-01-01

The Accelerated Lambda Iteration (ALI) technique was developed in stellar astrophysics at the beginning of 1990s for solving the non-LTE radiative transfer problem in atomic lines and multiplets in stellar atmospheres. It was later successfully applied to modeling the non-LTE emissions and radiative cooling/heating in the vibrational-rotational bands of molecules in planetary atmospheres. Similar to the standard lambda iterations ALI operates with the matrices of minimal dimension. However, it provides higher convergence rate and stability due to removing from the iterating process the photons trapped in the optically thick line cores. In the current ALI-ARMS (ALI for Atmospheric Radiation and Molecular Spectra) code version additional acceleration of calculations is provided by utilizing the opacity distribution function (ODF) approach and "decoupling". The former allows replacing the band branches by single lines of special shape, whereas the latter treats non-linearity caused by strong near-resonant vibration-vibrational level coupling without additional linearizing the statistical equilibrium equations. Latest code application for the non-LTE diagnostics of the molecular band emissions of Earth's and Martian atmospheres as well as for the non-LTE IR cooling/heating calculations are discussed.

DAPD: A Knowledgebase for Diabetes Associated Proteins.

PubMed

Gopinath, Krishnasamy; Jayakumararaj, Ramaraj; Karthikeyan, Muthusamy

2015-01-01

Recent advancements in genomics and proteomics provide a solid foundation for understanding the pathogenesis of diabetes. Proteomics of diabetes associated pathways help to identify the most potent target for the management of diabetes. The relevant datasets are scattered in various prominent sources which takes much time to select the therapeutic target for the clinical management of diabetes. However, additional information about target proteins is needed for validation. This lacuna may be resolved by linking diabetes associated genes, pathways and proteins and it will provide a strong base for the treatment and planning management strategies of diabetes. Thus, a web source "Diabetes Associated Proteins Database (DAPD)" has been developed to link the diabetes associated genes, pathways and proteins using PHP, MySQL. The current version of DAPD has been built with proteins associated with different types of diabetes. In addition, DAPD has been linked to external sources to gain the access to more participatory proteins and their pathway network. DAPD will reduce the time and it is expected to pave the way for the discovery of novel anti-diabetic leads using computational drug designing for diabetes management. DAPD is open accessed via following url www.mkarthikeyan.bioinfoau.org/dapd.

The development of an instrument for evaluating clinical teachers: involving stakeholders to determine content validity.

PubMed

Stalmeijer, Renée E; Dolmans, Diana H J M; Wolfhagen, Ineke H A P; Muijtjens, Arno M M; Scherpbier, Albert J J A

2008-01-01

Research indicates that the quality of supervision strongly influences the learning of medical students in clinical practice. Clinical teachers need feedback to improve their supervisory skills. The available instruments either lack a clear theoretical framework or are not suitable for providing feedback to individual teachers. We developed an evaluation instrument based on the 'cognitive apprenticeship model'. The aim was to estimate the content validity of the developed instrument. Item relevance was rated on a five-point scale (1 = highly irrelevant, 5 = highly relevant) by three groups of stakeholders in undergraduate clinical teaching: educationalists (N = 12), doctors (N = 16) and students (N = 12). Additionally, stakeholders commented on content, wording and omission of items. The items were generally rated as very relevant (Mean = 4.3, SD = 0.38, response = 95%) and any differences between the stakeholder groups were small. The results led to elimination of 4 items, rewording of 13 items and addition of 1 item. The cognitive apprenticeship model appears to offer a useful framework for the development of an evaluation instrument aimed at providing feedback to individual clinical teachers on the quality of student supervision. Further studies in larger populations will have to establish the instrument's statistical validity and generalizability.

Neurobehavioral perspectives on the distinction between fear and anxiety

PubMed Central

Perusini, Jennifer N.

2015-01-01

In this review, we discuss the usefulness of the distinction between fear and anxiety. The clinical use of the labels is ambiguous, often defining one in terms of the other. We first consider what a useful, objective, and scientifically valid definition would entail and then evaluate several fear/anxiety distinctions that have been made in the neurobiological literature. A strong distinction should specify the difference in conditions that lead to fear versus anxiety. Additionally, fear and anxiety should generate distinct sets of behaviors. Ideally, the two states should be supported by distinguishable neuroanatomical circuits. Such a conceptualization would be consistent with the National Institute of Mental Health's Research Domain Criteria (RDoc). The majority of neurobiological approaches to the fear versus anxiety distinction fail to differentiate the two states in terms of behavior, often using the exact same behavioral measures as indicators. Of the two that do, only Predatory Imminence Theory provides a distinction both in terms of cause and effect. Indeed, that approach provides a ready distinction of anxiety, fear, and panic in terms of both antecedent conditions and response selection rules. Additionally, it appeals to distinct neural circuits to generate these modes of action. PMID:26286652

Extracting duration information in a picture category decoding task using hidden Markov Models

NASA Astrophysics Data System (ADS)

Pfeiffer, Tim; Heinze, Nicolai; Frysch, Robert; Deouell, Leon Y.; Schoenfeld, Mircea A.; Knight, Robert T.; Rose, Georg

2016-04-01

Objective. Adapting classifiers for the purpose of brain signal decoding is a major challenge in brain-computer-interface (BCI) research. In a previous study we showed in principle that hidden Markov models (HMM) are a suitable alternative to the well-studied static classifiers. However, since we investigated a rather straightforward task, advantages from modeling of the signal could not be assessed. Approach. Here, we investigate a more complex data set in order to find out to what extent HMMs, as a dynamic classifier, can provide useful additional information. We show for a visual decoding problem that besides category information, HMMs can simultaneously decode picture duration without an additional training required. This decoding is based on a strong correlation that we found between picture duration and the behavior of the Viterbi paths. Main results. Decoding accuracies of up to 80% could be obtained for category and duration decoding with a single classifier trained on category information only. Significance. The extraction of multiple types of information using a single classifier enables the processing of more complex problems, while preserving good training results even on small databases. Therefore, it provides a convenient framework for online real-life BCI utilizations.

ADEA/AAL Institute for Allied Health Educators: Program Evaluation.

PubMed

Gadbury-Amyot, Cynthia C; Overman, Pamela R; Grzesikowski, Tami; Tucker-Lively, Felicia; Weinstein, George; Haden, N Karl

2015-05-01

Revised accreditation standards for dental and dental hygiene education programs have increased emphasis on faculty development that can improve teaching and learning, foster curricular change including use of teaching and learning technologies, and enhance retention and satisfaction of faculty. The American Dental Education Association (ADEA) and Academy for Academic Leadership (AAL) established the Institute for Allied Health Educators (IAHE) in 2007 to address faculty development needs for allied dental and allied health educators. In 2009, it was transitioned to an online program, which resulted in increased enrollment and diversity of participants. After seven years, a comprehensive program evaluation was warranted. The authors developed an online questionnaire based on Kirkpatrick's four-level model of training evaluation; for this study, levels one (satisfaction), two (knowledge and skill acquisition), and three (behavior change) were examined. Of the 400 program participants invited to take part in the study, a 38% response rate was achieved, with the majority indicating full-time faculty status. Nearly all (95-97%) of the respondents agreed or strongly agreed the program contributed to their teaching effectiveness, and 88-96% agreed or strongly agreed it enhanced their knowledge of educational concepts and strategies. In addition, 83% agreed or strongly agreed the program helped them develop new skills and confidence with technology, with 69% agreeing or strongly agreeing that it helped them incorporate technology into their own educational setting. Nearly 90% were highly positive or positive in their overall assessment of the program; 95% indicated they would recommend it to a colleague; and 80% agreed or strongly agreed they had discussed what they learned with faculty colleagues at their home institutions who had not attended the program. Positive findings from this evaluation provide evidence that the IAHE has been able to meet its goals.

Assessing the Utility of Strong Motion Data to Determine Static Ground Displacements During Great Megathrust Earthquakes: Tohoku and Iquique

NASA Astrophysics Data System (ADS)

Herman, M. W.; Furlong, K. P.; Hayes, G. P.; Benz, H.

2014-12-01

Strong motion accelerometers can record large amplitude shaking on-scale in the near-field of large earthquake ruptures; however, numerical integration of such records to determine displacement is typically unstable due to baseline changes (i.e., distortions in the zero value) that occur during strong shaking. We use datasets from the 2011 Mw 9.0 Tohoku earthquake to assess whether a relatively simple empirical correction scheme (Boore et al., 2002) can return accurate displacement waveforms useful for constraining details of the fault slip. The coseismic deformation resulting from the Tohoku earthquake was recorded by the Kiban Kyoshin network (KiK-net) of strong motion instruments as well as by a dense network of high-rate (1 Hz) GPS instruments. After baseline correcting the KiK-net records and integrating to displacement, over 85% of the KiK-net borehole instrument waveforms and over 75% of the KiK-net surface instrument waveforms match collocated 1 Hz GPS displacement time series. Most of the records that do not match the GPS-derived displacements following the baseline correction have large, systematic drifts that can be automatically identified by examining the slopes in the first 5-10 seconds of the velocity time series. We apply the same scheme to strong motion records from the 2014 Mw 8.2 Iquique earthquake. Close correspondence in both direction and amplitude between coseismic static offsets derived from the integrated strong motion time series and those predicted from a teleseismically-derived finite fault model, as well as displacement amplitudes consistent with InSAR-derived results, suggest that the correction scheme works successfully for the Iquique event. In the absence of GPS displacements, these strong motion-derived offsets provide constraints on the overall distribution of slip on the fault. In addition, the coseismic strong motion-derived displacement time series (50-100 s long) contain a near-field record of the temporal evolution of the rupture, supplementing teleseismic data and improving resolution of the location and timing of moment in finite fault models.

Characterization of organic gunshot residues in lead-free ammunition using a new sample collection device for liquid chromatography-quadrupole time-of-flight mass spectrometry.

PubMed

Benito, Sandra; Abrego, Zuriñe; Sánchez, Alicia; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

2015-01-01

The identification of characteristic organic gunshot residues (OGSR) provides conclusive evidence in the elucidation of elemental profiles when lead-free ammunition is fired. OGSR also prevents false negatives. Toward this aim, a quick and efficient method based on liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF) was developed to detect and identify 18 gunpowder additives in gunshot residues (GSR). The unequivocal identification of target analytes was assured by using MS/MS mode. Swabs were compared with home-modified tape lift supports covered with a PTFE layer to determine the better sampling technique. The modified tape lift provided better extraction recoveries and enabled the analysis of inorganic and organic GSR simultaneously. The developed method was applied to the analysis of GSR from four different lead-free ammunitions. Diphenylamine and its nitrated degradation products and centralites were identified in all samples, providing strong evidence of GSR. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Skills for social and academic success: a school-based intervention for social anxiety disorder in adolescents.

PubMed

Fisher, Paige H; Masia-Warner, Carrie; Klein, Rachel G

2004-12-01

This paper describes Skills for Academic and Social Success (SASS), a cognitive-behavioral, school-based intervention for adolescents with social anxiety disorder. Clinic-based treatment studies for socially anxious youth are reviewed, and a strong rationale for transporting empirically-based interventions into schools, such as SASS, is provided. The SASS program consists of 12, 40-min group sessions that emphasize social skills and in-vivo exposure. In addition to group sessions, students are seen individually at least twice and participate in 4 weekend social events with prosocial peers from their high schools. Meetings with teachers provide information about social anxiety and facilitate classroom exposures for socially anxious participants. Parents attend 2 psychoeducational meetings about social anxiety, its treatment, and approaches for managing their child's anxiety. Initial findings regarding the program's effectiveness are presented. We conclude by discussing the challenges involved in implementing treatment protocols in schools and provide suggestions to address these issues.

Tracking footprints of artificial selection in the dog genome.

PubMed

Akey, Joshua M; Ruhe, Alison L; Akey, Dayna T; Wong, Aaron K; Connelly, Caitlin F; Madeoy, Jennifer; Nicholas, Thomas J; Neff, Mark W

2010-01-19

The size, shape, and behavior of the modern domesticated dog has been sculpted by artificial selection for at least 14,000 years. The genetic substrates of selective breeding, however, remain largely unknown. Here, we describe a genome-wide scan for selection in 275 dogs from 10 phenotypically diverse breeds that were genotyped for over 21,000 autosomal SNPs. We identified 155 genomic regions that possess strong signatures of recent selection and contain candidate genes for phenotypes that vary most conspicuously among breeds, including size, coat color and texture, behavior, skeletal morphology, and physiology. In addition, we demonstrate a significant association between HAS2 and skin wrinkling in the Shar-Pei, and provide evidence that regulatory evolution has played a prominent role in the phenotypic diversification of modern dog breeds. Our results provide a first-generation map of selection in the dog, illustrate how such maps can rapidly inform the genetic basis of canine phenotypic variation, and provide a framework for delineating the mechanistic basis of how artificial selection promotes rapid and pronounced phenotypic evolution.

MSFC's Advanced Space Propulsion Formulation Task

NASA Technical Reports Server (NTRS)

Huebner, Lawrence D.; Gerrish, Harold P.; Robinson, Joel W.; Taylor, Terry L.

2012-01-01

In NASA s Fiscal Year 2012, a small project was undertaken to provide additional substance, depth, and activity knowledge to the technology areas identified in the In-Space Propulsion Systems Roadmap, Technology Area 02 (TA-02), as created under the auspices of the NASA Office of the Chief Technologist (OCT). This roadmap was divided into four basic groups: (1) Chemical Propulsion, (2) Non-chemical Propulsion, (3) Advanced (TRL<3) Propulsion Technologies, and (4) Supporting Technologies. The first two were grouped according to the governing physics. The third group captured technologies and physic concepts that are at a lower TRL level. The fourth group identified pertinent technical areas that are strongly coupled with these related areas which could allow significant improvements in performance. There were a total of 45 technologies identified in TA-02, and 25 of these were studied in this formulation task. The goal of this task was to provide OCT with a knowledge-base for decisionmaking on advanced space propulsion technologies and not waste money by unintentionally repeating past projects or funding the technologies with minor impacts. This formulation task developed the next level of detail for technologies described and provides context to OCT where investments should be made. The presentation will begin with the list of technologies from TA-02, how they were prioritized for this study, and details on what additional data was captured for the technologies studied. Following this, some samples of the documentation will be provided, followed by plans on how the data will be made accessible.

In vivo study of ALA PLGA nanoparticles-mediated PDT for treating cutaneous squamous cell carcinoma

NASA Astrophysics Data System (ADS)

Wang, Xiaojie; Shi, Lei; Huang, Zheng; Wang, Xiuli

2014-09-01

Background: Squamous cell carcinoma (SCC) is a common skin cancer and its treatment is still a challenge. Although topical photodynamic therapy (PDT) is effective for treating in situ and superficial SCC, the effectiveness of topical ALA delivery to thick SCC can be limited by its bioavailability. Polylactic-co-glycolic acid nanopartieles (PLGA NPs) might provide a promising ALA delivery strategy. The aim of this study was to evaluate the efficacy of ALA PLGA NPs PDT for the treatment of cutaneous SCC in a mouse model. Methods: ALA loaded PLGA NPs were prepared and characterized. The therapeutic efficacy of ALA PLGA NP mediated PDT in treating UV-induced cutaneous SCC in the mice model were examined. Results: In vivo study showed that ALA PLGA NPs PDT were more effective than free ALA of the same concentration in treating mouse cutaneous SCC. Conclusion: ALA PLGA NPs provides a promising strategy for delivering ALA and treating cutaneous SCC.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wayne Pennington; Mohamed Ibrahim; Roger Turpening

Crosswell seismic surveys were conducted at two fields in northern Michigan. One of these, Springdale, included two monitor wells that are located external to the reef, and the other, Coldspring, employed two production wells within the reef. The Springdale wells extended to much greater depths than the reef, and imaging was conducted from above and from beneath the reef. The resulting seismic images provide the best views of pinnacle Niagaran reefs obtained to date. The tops of the reservoirs can be clearly distinguished, and their lateral extent or dipping edges can be observed along the profile. Reflecting events internal tomore » the reef are evident; some of them are fairly continuous across the reef and others are discontinuous. Inversion of the seismic data indicates which events represent zones of higher porosity and which are lower porosity or even anhydrite plugged. The full stacked image includes angles that are beyond critical for many of the interfaces, and some reflections are visible only for a small range of angles, presumably near their critical angle. Stacking these angles in provides an opportunity for these events to be seen on the stacked image, where otherwise they would have been unrecognized. For inversion, however, the complexity associated with phase changes beyond critical can lead to poor results, and elastic inversion of partial angle stacks may be best conducted with restrictions to angles less than critical. Strong apparent attenuation of signals occurs when seismic ray paths pass through the upper part of the Springdale reservoir; this may be due to intrinsic attenuation and/or scattering of events due to the locally strongly varying gas saturation and extremely low fluid pressures. Signal-to-noise limitations become evident far from the source well in the Coldspring study, probably because the raw data were strongly affected by tube-wave noise generated by flow through the perforation of the receiver well. The seismic images obtained, and interpretations of them, as assisted by Amplitude-versus-Angle studies and accompanying inversion, provide additional insight into the internal geometry of these two reefs and provide data that should be useful for reservoir management.« less

Migration of conservative and sorbing radionuclides in heterogeneous fractured rock aquifers at the Nevada Test Site

NASA Astrophysics Data System (ADS)

Boryta, J. R.; Wolfsberg, A. V.

2003-12-01

The Nevada Test Site (NTS) is the United States continental nuclear weapons testing site. The larger underground tests, including BENHAM and TYBO, were conducted at Pahute Mesa. The BENHAM test, conducted in 1968, was detonated 1.4 km below the surface and the TYBO test, conducted in 1975, was detonated at a depth of 765 m. Between 1996 and 1998, several radionuclides were discovered in trace concentrations in a monitoring well complex 273 m from TYBO and 1300 m from BENHAM. Previous studies associated with these measurements have focused primarily on a) plutonium discovered in the observation wells, which was identified through isotopic finger printing as originating at BENHAM, b) colloid-facilitated plutonium transport processes, and c) vertical convection in subsurface nuclear test collapse chimneys. In addition to plutonium, several other non-, weakly-, and strongly-sorbing radionuclides were discovered in trace concentrations in the observation wells, including tritium, carbon-14, chlorine-36, iodine-129, technetium-99, neptunium-237, strontium-90, cesium-137, americium-241, and europium-152,154,155. The range in retardation processes affecting these different radionuclides provides additional information for assessing groundwater solute transport model formulations. For all radionuclides, simulation results are most sensitive to the fracture porosity and fracture aperture. Additionally, for weakly sorbing Np, simulation results are highly sensitive to the matrix sorption coefficient. For strongly sorbing species, migration in the absence of colloids can only be simulated if fracture apertures are set very large, reducing the amount of diffusion that can occur. For these species, colloid-facilitated transport appears to be a more likely explanation for the measurements. This is corroborated with colloid-transport model simulations.

Improved peak detection in mass spectrum by incorporating continuous wavelet transform-based pattern matching.

PubMed

Du, Pan; Kibbe, Warren A; Lin, Simon M

2006-09-01

A major problem for current peak detection algorithms is that noise in mass spectrometry (MS) spectra gives rise to a high rate of false positives. The false positive rate is especially problematic in detecting peaks with low amplitudes. Usually, various baseline correction algorithms and smoothing methods are applied before attempting peak detection. This approach is very sensitive to the amount of smoothing and aggressiveness of the baseline correction, which contribute to making peak detection results inconsistent between runs, instrumentation and analysis methods. Most peak detection algorithms simply identify peaks based on amplitude, ignoring the additional information present in the shape of the peaks in a spectrum. In our experience, 'true' peaks have characteristic shapes, and providing a shape-matching function that provides a 'goodness of fit' coefficient should provide a more robust peak identification method. Based on these observations, a continuous wavelet transform (CWT)-based peak detection algorithm has been devised that identifies peaks with different scales and amplitudes. By transforming the spectrum into wavelet space, the pattern-matching problem is simplified and in addition provides a powerful technique for identifying and separating the signal from the spike noise and colored noise. This transformation, with the additional information provided by the 2D CWT coefficients can greatly enhance the effective signal-to-noise ratio. Furthermore, with this technique no baseline removal or peak smoothing preprocessing steps are required before peak detection, and this improves the robustness of peak detection under a variety of conditions. The algorithm was evaluated with SELDI-TOF spectra with known polypeptide positions. Comparisons with two other popular algorithms were performed. The results show the CWT-based algorithm can identify both strong and weak peaks while keeping false positive rate low. The algorithm is implemented in R and will be included as an open source module in the Bioconductor project.

Solving search problems by strongly simulating quantum circuits

PubMed Central

Johnson, T. H.; Biamonte, J. D.; Clark, S. R.; Jaksch, D.

2013-01-01

Simulating quantum circuits using classical computers lets us analyse the inner workings of quantum algorithms. The most complete type of simulation, strong simulation, is believed to be generally inefficient. Nevertheless, several efficient strong simulation techniques are known for restricted families of quantum circuits and we develop an additional technique in this article. Further, we show that strong simulation algorithms perform another fundamental task: solving search problems. Efficient strong simulation techniques allow solutions to a class of search problems to be counted and found efficiently. This enhances the utility of strong simulation methods, known or yet to be discovered, and extends the class of search problems known to be efficiently simulable. Relating strong simulation to search problems also bounds the computational power of efficiently strongly simulable circuits; if they could solve all problems in P this would imply that all problems in NP and #P could be solved in polynomial time. PMID:23390585

The Effects of Extra-Somatic Weapons on the Evolution of Human Cooperation towards Non-Kin

PubMed Central

Phillips, Tim; Li, Jiawei; Kendall, Graham

2014-01-01

Human cooperation and altruism towards non-kin is a major evolutionary puzzle, as is ‘strong reciprocity’ where no present or future rewards accrue to the co-operator/altruist. Here, we test the hypothesis that the development of extra-somatic weapons could have influenced the evolution of human cooperative behaviour, thus providing a new explanation for these two puzzles. Widespread weapons use could have made disputes within hominin groups far more lethal and also equalized power between individuals. In such a cultural niche non-cooperators might well have become involved in such lethal disputes at a higher frequency than cooperators, thereby increasing the relative fitness of genes associated with cooperative behaviour. We employ two versions of the evolutionary Iterated Prisoner's Dilemma (IPD) model – one where weapons use is simulated and one where it is not. We then measured the performance of 25 IPD strategies to evaluate the effects of weapons use on them. We found that cooperative strategies performed significantly better, and non-cooperative strategies significantly worse, under simulated weapons use. Importantly, the performance of an ‘Always Cooperate’ IPD strategy, equivalent to that of ‘strong reciprocity’, improved significantly more than that of all other cooperative strategies. We conclude that the development of extra-somatic weapons throws new light on the evolution of human altruistic and cooperative behaviour, and particularly ‘strong reciprocity’. The notion that distinctively human altruism and cooperation could have been an adaptive trait in a past environment that is no longer evident in the modern world provides a novel addition to theory that seeks to account for this major evolutionary puzzle. PMID:24796325

Allochronic speciation, secondary contact, and reproductive character displacement in periodical cicadas (Hemiptera: Magicicada spp.): genetic, morphological, and behavioural evidence.

PubMed

Cooley, J R; Simon, C; Marshall, D C; Slon, K; Ehrhardt, C

2001-03-01

Periodical cicadas have proven useful in testing a variety of ecological and evolutionary hypotheses because of their unusual life history, extraordinary abundance, and wide geographical range. Periodical cicadas provide the best examples of synchronous periodicity and predator satiation in the animal kingdom, and are excellent illustrations of habitat partitioning (by the three morphologically distinct species groups), incipient species (the year classes or broods), and cryptic species (a newly discovered 13-year species, Magicicada neotredecim). They are particularly useful for exploring questions regarding speciation via temporal isolation, or allochronic speciation. Recently, data were presented that provided strong support for an instance of allochronic speciation by life-cycle switching. This speciation event resulted in the formation of a new 13-year species from a 17-year species and led to secondary contact between two formerly separated lineages, one represented by the new 13-year cicadas (and their 17-year ancestors), and the other represented by the pre-existing 13-year cicadas. Allozyme frequency data, mitochondrial DNA (mtDNA), and abdominal colour were shown to be correlated genetic markers supporting the life-cycle switching/allochronic speciation hypothesis. In addition, a striking pattern of reproductive character displacement in male call pitch and female pitch preference between the two 13-year species was discovered. In this paper we report a strong association between calling song pitch and mtDNA haplotype for 101 individuals from a single locality within the M. tredecim/M. neotredecim contact zone and a strong association between abdomen colour and mtDNA haplotype. We conclude by reviewing proposed mechanisms for allochronic speciation and reproductive character displacement.

Pre-Melting in Iron and Iron Alloys at Earth's Core Conditions: Results from Ab Initio Molecular Dynamics Calculations

NASA Astrophysics Data System (ADS)

Vocadlo, L.; Martorell, B.; Brodholt, J. P.; Wood, I. G.

2014-12-01

Seismically determined S-wave velocities in the Earth's inner core are observed to be much lower (10-30%) than those generally inferred from mineral physics. This is a remarkably large discrepancy - mineralogical models for the mantle and the outer core match the observed velocities to around 1%. In no other large volume of the Earth does such a difference exist. There have been a number of arguments put forward over the years to account for the difference, but none have been universally accepted and our inability to explain the seismic velocities of the inner core remains an uncomfortable truth. Here, we present results from ab initio molecular dynamics calculations performed at 360 GPa and core temperatures on hcp and fcc iron, and on fcc-Fe alloyed with nickel and hcp-Fe alloyed with silicon. The calculated shear modulus, and therefore seismic velocities, of pure hcp-Fe reduces dramatically just prior to melting, providing an elegant explanation for the observed velocities. Calculations on fcc-Fe show no such strong reduction in VS, with a transformation to an hcp-type structure prior to melting; addition of 6.5 atm% and 13 atm% Ni to fcc-Fe raises the temperature of this transition. When silicon is added to hcp-Fe, the pre-melting behaviour is found to be very similar to that of pure hcp-Fe with a strong nonlinear shear weakening just before melting and a corresponding reduction in VS. Because temperatures range from T/Tm = 1 at the inner-outer core boundary to T/Tm ≈ 0.99 at the centre, this strong nonlinear effect on VS should occur in the inner core, providing a compelling explanation for the low VS observed.

Functional traits determine tree growth and ecosystem productivity of a tropical montane forest: Insights from a long-term nutrient manipulation experiment.

PubMed

Báez, Selene; Homeier, Jürgen

2018-01-01

Trait-response effects are critical to forecast community structure and biomass production in highly diverse tropical forests. Ecological theory and few observation studies indicate that trees with acquisitive functional traits would respond more strongly to higher resource availability than those with conservative traits. We assessed how long-term tree growth in experimental nutrient addition plots (N, P, and N + P) varied as a function of morphological traits, tree size, and species identity. We also evaluated how trait-based responses affected stand scale biomass production considering the community structure. We found that tree growth depended on interactions between functional traits and the type or combination of nutrients added. Common species with acquisitive functional traits responded more strongly to nutrient addition, mainly to N + P. Phosphorous enhanced the growth rates of species with acquisitive and conservative traits, had mostly positive effects on common species and neutral or negative effects in rare species. Moreover, trees receiving N + P grew faster irrespective of their initial size relative to trees in control or to trees in other treatment plots. Finally, species responses were highly idiosyncratic suggesting that community processes including competition and niche dimensionality may be altered under increased resource availability. We found no statistically significant effects of nutrient additions on aboveground biomass productivity because acquisitive species had a limited potential to increase their biomass, possibly due to their generally lower wood density. In contrast, P addition increased the growth rates of species characterized by more conservative resource strategies (with higher wood density) that were poorly represented in the plant community. We provide the first long-term experimental evidence that trait-based responses, community structure, and community processes modulate the effects of increased nutrient availability on biomass productivity in a tropical forest. © 2017 John Wiley & Sons Ltd.

Glucose Uptake and Its Effect on Gene Expression in Prochlorococcus

PubMed Central

Gómez-Baena, Guadalupe; López-Lozano, Antonio; Gil-Martínez, Jorge; Lucena, José Manuel; Diez, Jesús; Candau, Pedro; García-Fernández, Jose Manuel

2008-01-01

The marine cyanobacteria Prochlorococcus have been considered photoautotrophic microorganisms, although the utilization of exogenous sugars has never been specifically addressed in them. We studied glucose uptake in different high irradiance- and low irradiance-adapted Prochlorococcus strains, as well as the effect of glucose addition on the expression of several glucose-related genes. Glucose uptake was measured by adding radiolabelled glucose to Prochlorococcus cultures, followed by flow cytometry coupled with cell sorting in order to separate Prochlorococcus cells from bacterial contaminants. Sorted cells were recovered by filtration and their radioactivity measured. The expression, after glucose addition, of several genes (involved in glucose metabolism, and in nitrogen assimilation and its regulation) was determined in the low irradiance-adapted Prochlorococcus SS120 strain by semi-quantitative real time RT-PCR, using the rnpB gene as internal control. Our results demonstrate for the first time that the Prochlorococcus strains studied in this work take up glucose at significant rates even at concentrations close to those found in the oceans, and also exclude the possibility of this uptake being carried out by eventual bacterial contaminants, since only Prochlorococcus cells were used for radioactivity measurements. Besides, we show that the expression of a number of genes involved in glucose utilization (namely zwf, gnd and dld, encoding glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and lactate dehydrogenase, respectively) is strongly increased upon glucose addition to cultures of the SS120 strain. This fact, taken together with the magnitude of the glucose uptake, clearly indicates the physiological importance of the phenomenon. Given the significant contribution of Prochlorococcus to the global primary production, these findings have strong implications for the understanding of the phytoplankton role in the carbon cycle in nature. Besides, the ability of assimilating carbon molecules could provide additional hints to comprehend the ecological success of Prochlorococcus. PMID:18941506

Recent Additions for 1999

EPA Science Inventory

December 8, 1999

Summary Of The U.S. EPA Colloquium On a Framework for Human Health Risk Assessment
EPA/600/R-99/001 and EPA/600/R-98/155
The U.S. ...

Observations of the Ultraviolet Spectra of Carbon White Dwarfs

NASA Technical Reports Server (NTRS)

Wagner, G. A.

1982-01-01

Strong ultraviolet carbon lines were detected in additional white DC (continuous visual spectra) dwarfs using the IUE. These lines are not seen in the ultraviolet spectrum of the cool DC star Stein 2051 B. The bright DA white dwarf LB 3303 has a strong unidentified absorption near lambda 1400.

Lewis base catalyzed aldol additions of chiral trichlorosilyl enolates and silyl enol ethers.

PubMed

Denmark, Scott E; Fujimori, Shinji; Pham, Son M

2005-12-23

[structures: see text] The consequences of double diastereodifferentiation in chiral Lewis base catalyzed aldol additions using chiral enoxysilanes derived from lactate, 3-hydroxyisobutyrate, and 3-hydroxybutyrate have been investigated. Trichlorosilyl enolates derived from the chiral methyl and ethyl ketones were subjected to aldolization in the presence of phosphoramides, and the intrinsic selectivity of these enolates and the external stereoinduction from chiral catalyst were studied. In the reactions with the lactate derived enolate, the strong internal stereoinduction dominated the stereochemical outcome of the aldol addition. For the 3-hydroxyisobutyrate- and 3-hydroxybutyrate derived enolates, the catalyst-controlled diastereoselectivities were observed, and the resident stereogenic centers exerted marginal influence. The corresponding trimethylsilyl enol ethers were employed in SiCl4/bisphosphoramide catalyzed aldol additions, and the effect of double diastereodifferentiation was also investigated. The overall diastereoselection of the process was again controlled by the strong external influence of the catalyst.

Generalization of Associations of Kidney-Related Genetic Loci to American Indians

PubMed Central

Haack, Karin; Almasy, Laura; Laston, Sandra; Lee, Elisa T.; Best, Lyle G.; Fabsitz, Richard R.; MacCluer, Jean W.; Howard, Barbara V.; Umans, Jason G.; Cole, Shelley A.

2014-01-01

Summary Background and objectives CKD disproportionally affects American Indians, who similar to other populations, show genetic susceptibility to kidney outcomes. Recent studies have identified several loci associated with kidney traits, but their relevance in American Indians is unknown. Design, setting, participants, & measurements This study used data from a large, family-based genetic study of American Indians (the Strong Heart Family Study), which includes 94 multigenerational families enrolled from communities located in Oklahoma, the Dakotas, and Arizona. Individuals were recruited from the Strong Heart Study, a population-based study of cardiovascular disease in American Indians. This study selected 25 single nucleotide polymorphisms in 23 loci identified from recently published kidney-related genome-wide association studies in individuals of European ancestry to evaluate their associations with kidney function (estimated GFR; individuals 18 years or older, up to 3282 individuals) and albuminuria (urinary albumin to creatinine ratio; n=3552) in the Strong Heart Family Study. This study also examined the association of single nucleotide polymorphisms in the APOL1 region with estimated GFR in 1121 Strong Heart Family Study participants. GFR was estimated using the abbreviated Modification of Diet in Renal Disease Equation. Additive genetic models adjusted for age and sex were used. Results This study identified significant associations of single nucleotide polymorphisms with estimated GFR in or nearby PRKAG2, SLC6A13, UBE2Q2, PIP5K1B, and WDR72 (P<2.1 × 10-3 to account for multiple testing). Single nucleotide polymorphisms in these loci explained 2.2% of the estimated GFR total variance and 2.9% of its heritability. An intronic variant of BCAS3 was significantly associated with urinary albumin to creatinine ratio. APOL1 single nucleotide polymorphisms were not associated with estimated GFR in a single variant test or haplotype analyses, and the at-risk variants identified in individuals with African ancestry were not detected in DNA sequencing of American Indians. Conclusion This study extends the genetic associations of loci affecting kidney function to American Indians, a population at high risk of kidney disease, and provides additional support for a potential biologic relevance of these loci across ancestries. PMID:24311711

The Variable Transition State in Polar Additions to Pi Bonds

ERIC Educational Resources Information Center

Weiss, Hilton M.

2010-01-01

A vast majority of polar additions of Bronsted acids to alkynes involve a termolecular transition state. With strong acids, considerable positive charge is developed on carbon and Markovnikov addition predominates. In less acidic solutions, however, the reaction is much slower and the transition state more closely resembles the olefinic product.…

Tigers Need Cover: Multi-Scale Occupancy Study of the Big Cat in Sumatran Forest and Plantation Landscapes

PubMed Central

Sunarto, Sunarto; Kelly, Marcella J.; Parakkasi, Karmila; Klenzendorf, Sybille; Septayuda, Eka; Kurniawan, Harry

2012-01-01

The critically endangered Sumatran tiger (Panthera tigris sumatrae Pocock, 1929) is generally known as a forest-dependent animal. With large-scale conversion of forests into plantations, however, it is crucial for restoration efforts to understand to what extent tigers use modified habitats. We investigated tiger-habitat relationships at 2 spatial scales: occupancy across the landscape and habitat use within the home range. Across major landcover types in central Sumatra, we conducted systematic detection, non-detection sign surveys in 47, 17×17 km grid cells. Within each cell, we surveyed 40, 1-km transects and recorded tiger detections and habitat variables in 100 m segments totaling 1,857 km surveyed. We found that tigers strongly preferred forest and used plantations of acacia and oilpalm, far less than their availability. Tiger probability of occupancy covaried positively and strongly with altitude, positively with forest area, and negatively with distance-to-forest centroids. At the fine scale, probability of habitat use by tigers across landcover types covaried positively and strongly with understory cover and altitude, and negatively and strongly with human settlement. Within forest areas, tigers strongly preferred sites that are farther from water bodies, higher in altitude, farther from edge, and closer to centroid of large forest block; and strongly preferred sites with thicker understory cover, lower level of disturbance, higher altitude, and steeper slope. These results indicate that to thrive, tigers depend on the existence of large contiguous forest blocks, and that with adjustments in plantation management, tigers could use mosaics of plantations (as additional roaming zones), riparian forests (as corridors) and smaller forest patches (as stepping stones), potentially maintaining a metapopulation structure in fragmented landscapes. This study highlights the importance of a multi-spatial scale analysis and provides crucial information relevant to restoring tigers and other wildlife in forest and plantation landscapes through improvement in habitat extent, quality, and connectivity. PMID:22292063

Tigers need cover: multi-scale occupancy study of the big cat in Sumatran forest and plantation landscapes.

PubMed

Sunarto, Sunarto; Kelly, Marcella J; Parakkasi, Karmila; Klenzendorf, Sybille; Septayuda, Eka; Kurniawan, Harry

2012-01-01

The critically endangered Sumatran tiger (Panthera tigris sumatrae Pocock, 1929) is generally known as a forest-dependent animal. With large-scale conversion of forests into plantations, however, it is crucial for restoration efforts to understand to what extent tigers use modified habitats. We investigated tiger-habitat relationships at 2 spatial scales: occupancy across the landscape and habitat use within the home range. Across major landcover types in central Sumatra, we conducted systematic detection, non-detection sign surveys in 47, 17×17 km grid cells. Within each cell, we surveyed 40, 1-km transects and recorded tiger detections and habitat variables in 100 m segments totaling 1,857 km surveyed. We found that tigers strongly preferred forest and used plantations of acacia and oilpalm, far less than their availability. Tiger probability of occupancy covaried positively and strongly with altitude, positively with forest area, and negatively with distance-to-forest centroids. At the fine scale, probability of habitat use by tigers across landcover types covaried positively and strongly with understory cover and altitude, and negatively and strongly with human settlement. Within forest areas, tigers strongly preferred sites that are farther from water bodies, higher in altitude, farther from edge, and closer to centroid of large forest block; and strongly preferred sites with thicker understory cover, lower level of disturbance, higher altitude, and steeper slope. These results indicate that to thrive, tigers depend on the existence of large contiguous forest blocks, and that with adjustments in plantation management, tigers could use mosaics of plantations (as additional roaming zones), riparian forests (as corridors) and smaller forest patches (as stepping stones), potentially maintaining a metapopulation structure in fragmented landscapes. This study highlights the importance of a multi-spatial scale analysis and provides crucial information relevant to restoring tigers and other wildlife in forest and plantation landscapes through improvement in habitat extent, quality, and connectivity.

Justice in Health Care Decision-Making: Patients’ Appraisals of Health Care Providers and Health Plan Representatives

PubMed Central

Fondacaro, Mark; Frogner, Bianca; Moos, Rudolf

2010-01-01

This study describes the development of two versions of a Health Care Justice Inventory (HCJI). One version focuses on patients’ interactions with their providers (HCJI-P) and the other focuses on patients’ interactions with the representatives of their health plans (HCJI-HP). Each version of the HCJI assesses patients’ appraisals of their interactions (with either their Provider or representatives of their Health Plan) along three common dimensions of procedural justice: Trust, Impartiality, and Participation. Both the Provider and Health Plan scales assess indices that are relatively independent of patients’ demographic characteristics. In addition, patients’ appraisals of their interactions with their provider were only moderately related to their appraisals of their interactions with representatives of their health plan, indicating that the Provider and Health Plan scales tap distinct aspects of patients’ overall experience with the health care system. Overall, procedural justice dimensions were significantly related to patient satisfaction in both the Provider and the Health Plan contexts. As predicted, procedural justice factors were more strongly tied to patient satisfaction in the Provider than in the Health Plan context, and health care decisions based on distributive justice principles of Need (rather than Equity or Equality) were most closely tied to patient satisfaction in both contexts. PMID:16021741

The partitioning of copper among selected phases of geologic media of two porphyry copper districts, Puerto Rico

USGS Publications Warehouse

Learned, R.E.; Chao, T.T.; Sanzolone, R.F.

1981-01-01

In experiments designed to determine the manner in which copper is partitioned among selected phases that constitute geologic media, we have applied the five-step sequential extraction procedure of Chao and Theobald to the analysis of drill core, soils, and stream sediments of the Rio Vivi and Rio Tanama porphyry copper districts of Puerto Rico. The extraction procedure affords a convenient means of determining the trace-metal content of the following fractions: (1) Mn oxides and "reactive" Fe oxides; (2) "amorphous" Fe oxides; (3) "crystalline" Fe oxides; (4) sulfides and magnetite; and (5) silicates. An additional extraction between steps (1) and (2) was performed to determine organic-related copper in stream sediments. The experimental results indicate that apportionment of copper among phases constituting geologic media is a function of geochemical environment. Distinctive partitioning patterns were derived from the analysis of drill core from each of three geochemical zones: (a) the supergene zone of oxidation; (b) the supergene zone of enrichment; and (c) the hypogene zone; and similarly, from the analysis of; (d) soils on a weakly leached capping; (e) soils on a strongly leached capping; and (f) active stream sediment. The experimental results also show that geochemical contrasts (anomaly-to-background ratios) vary widely among the five fractions of each sampling medium investigated, and that at least one fraction of each medium provides substantially stronger contrast than does the bulk medium. Fraction (1) provides optimal contrast for stream sediments of the district; fraction (2) provides optimal contrast for soils on a weakly leached capping; fraction (3) provides optimal contrast for soils on a strongly leached capping. Selective extraction procedures appear to have important applications to the orientation and interpretive stages of geochemical exploration. Further investigation and testing of a similar nature are recommended. ?? 1981.

Strong refraction near the Venus surface - Effects observed by descent probes

NASA Technical Reports Server (NTRS)

Croft, T. A.

1982-01-01

The telemetry signals from Pioneer Venus probes indicated the strong downward refraction of radio waves. As the probes descended, the strength of the direct signal decreased because of absorption and refractive defocusing. During the last 30 km of descent there was a second measured component in addition to the direct signal. Strong atmospheric reaction is important in strengthening echoes that are scattered toward the earth. Such surface-reflected signals are good indicators of horizontal winds.

Bonded exciplex formation: electronic and stereoelectronic effects.

PubMed

Wang, Yingsheng; Haze, Olesya; Dinnocenzo, Joseph P; Farid, Samir; Farid, Ramy S; Gould, Ian R

2008-12-18

As recently proposed, the singlet-excited states of several cyanoaromatics react with pyridine via bonded-exciplex formation, a novel concept in photochemical charge transfer reactions. Presented here are electronic and steric effects on the quenching rate constants, which provide valuable support for the model. Additionally, excited-state quenching in poly(vinylpyridine) is strongly inhibited both relative to that in neat pyridine and also to conventional exciplex formation in polymers, consistent with a restrictive orientational requirement for the formation of bonded exciplexes. Examples of competing reactions to form both conventional and bonded exciplexes are presented, which illustrate the delicate balance between these two processes when their reaction energetics are similar. Experimental and computational evidence is provided for the formation of a bonded exciplex in the reaction of the singlet excited state of 2,6,9,10-tetracyanoanthracene (TCA) with an oxygen-substituted donor, dioxane, thus expanding the scope of bonded exciplexes.

Self-Assembly of Measles Virus Nucleocapsid-like Particles: Kinetics and RNA Sequence Dependence.

PubMed

Milles, Sigrid; Jensen, Malene Ringkjøbing; Communie, Guillaume; Maurin, Damien; Schoehn, Guy; Ruigrok, Rob W H; Blackledge, Martin

2016-08-01

Measles virus RNA genomes are packaged into helical nucleocapsids (NCs), comprising thousands of nucleo-proteins (N) that bind the entire genome. N-RNA provides the template for replication and transcription by the viral polymerase and is a promising target for viral inhibition. Elucidation of mechanisms regulating this process has been severely hampered by the inability to controllably assemble NCs. Here, we demonstrate self-organization of N into NC-like particles in vitro upon addition of RNA, providing a simple and versatile tool for investigating assembly. Real-time NMR and fluorescence spectroscopy reveals biphasic assembly kinetics. Remarkably, assembly depends strongly on the RNA-sequence, with the genomic 5' end and poly-Adenine sequences assembling efficiently, while sequences such as poly-Uracil are incompetent for NC formation. This observation has important consequences for understanding the assembly process. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Production of gluten and germ by ethanol fermentation of raw corn

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-01-01

The Illinois ethanol fuel industry has grown to be an important part of our state's economy over the past 10 years. It provides an additional market for Illinois' abundant corn production, provides many industrial jobs, and substitutes a home-grown renewable energy resource for imported oil. More than 30 percent of all gasoline sold in Illinois contains 10 percent ethanol. The economics of producing ethanol from corn is strongly affected by the byproduct value and by the energy required in the production process. This document reports on efforts to research a new microbial process that would improve the ethanol fermentation processmore » in both these areas. The new process allows direct fermentation of corn starch to ethanol without the usual requirement of cooking the corn. This reduces the amount of energy needed for production and recovers the protein-containing gluten and oil-containing germ with all of the original food value intact.« less

Religious Beliefs and Cancer Screening Behaviors among Catholic Latinos: Implications for Faith-based Interventions

PubMed Central

Allen, Jennifer D.; Leyva, Bryan; Torres, María Idalí; Ospino, Hosffman; Tom, Laura; Rustan, Sarah; Bartholomew, Amanda

2014-01-01

Although most U.S. Latinos identify as Catholic, few studies have focused on the influence of this religious tradition on health beliefs among this population. This study explores the role of Catholic religious teachings, practices, and ministry on cancer screening knowledge, attitudes and behaviors among Latinos. Eight focus groups were conducted with 67 Catholic Latino parishioners in Massachusetts. Qualitative analysis provided evidence of strong reliance on faith, God, and parish leaders for health concerns. Parishes were described as vital sources of health and social support, playing a central role in the community's health. Participants emphasized that their religious beliefs promote positive health behaviors and health care utilization, including the use of cancer screening services. In addition, they expressed willingness to participate in cancer education programs located at their parishes and provided practical recommendations for implementing health programs in parishes. Implications for culturally appropriate health communication and faith-based interventions are discussed. PMID:24858865

Static axisymmetric equilibria in general relativistic magnetohydrodynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nunez, Manuel

2008-01-15

While the definition of static equilibria is not clear in a general relativistic context, in many cases of astrophysical interest a natural 3+1 split exists which allows us to define physically meaningful spatial and temporal coordinates. We study the possibility of axisymmetric magnetohydrodynamic equilibria in this setting. The presence of a nontrivial shift velocity provides a constraint not present in the Newtonian case, while the momentum equation may be set in a Grad-Shafranov-like form with the presence of additional terms involving the space-time metric coefficients. It is found that whenever the magnetic field or the shift velocity possesses poloidal component,more » the existence of even local static equilibria demands that the metric parameters satisfy such strong conditions that these equilibria are extremely unlikely. Only very particular cases such as purely toroidal fields and shifts yield existence of equilibria, provided we are able to choose arbitrarily the plasma pressure and density.« less

Emotion and Perception: The Role of Affective Information

PubMed Central

Zadra, Jonathan R.; Clore, Gerald L.

2011-01-01

Visual perception and emotion are traditionally considered separate domains of study. In this article, however, we review research showing them to be less separable that usually assumed. In fact, emotions routinely affect how and what we see. Fear, for example, can affect low-level visual processes, sad moods can alter susceptibility to visual illusions, and goal-directed desires can change the apparent size of goal-relevant objects. In addition, the layout of the physical environment, including the apparent steepness of a hill and the distance to the ground from a balcony can both be affected by emotional states. We propose that emotions provide embodied information about the costs and benefits of anticipated action, information that can be used automatically and immediately, circumventing the need for cogitating on the possible consequences of potential actions. Emotions thus provide a strong motivating influence on how the environment is perceived. PMID:22039565

Colorado Learning Difficulties Questionnaire:Validation of a parent-report screening measure

PubMed Central

Willcutt, Erik G.; Boada, Richard; Riddle, Margaret W.; Chhabildas, Nomita; DeFries, John C.; Pennington, Bruce F.

2011-01-01

This study evaluated the internal structure and convergent and discriminant evidence for the Colorado Learning Difficulties Questionnaire (CLDQ), a 20-item parent-report rating scale that was developed to provide a brief screening measure for learning difficulties. CLDQ ratings were obtained from parents of children in two large community samples and two samples from clinics that specialize in the assessment of learning disabilities and related disorders (total N = 8,004). Exploratory and confirmatory factor analyses revealed five correlated but separable dimensions that were labeled reading, math, social cognition, social anxiety, and spatial difficulties. Results revealed strong convergent and discriminant evidence for the CLDQ Reading scale, suggesting that this scale may provide a useful method to screen for reading difficulties in both research studies and clinical settings. Results are also promising for the other four CLDQ scales, but additional research is needed to refine each of these measures. PMID:21574721

Temperature-independent fiber-Bragg-grating-based atmospheric pressure sensor

NASA Astrophysics Data System (ADS)

Zhang, Zhiguo; Shen, Chunyan; Li, Luming

2018-03-01

Atmospheric pressure is an important way to achieve a high degree of measurement for modern aircrafts, moreover, it is also an indispensable parameter in the meteorological telemetry system. With the development of society, people are increasingly concerned about the weather. Accurate and convenient atmospheric pressure parameters can provide strong support for meteorological analysis. However, electronic atmospheric pressure sensors currently in application suffer from several shortcomings. After an analysis and discussion, we propose an innovative structural design, in which a vacuum membrane box and a temperature-independent strain sensor based on an equal strength cantilever beam structure and fiber Bragg grating (FBG) sensors are used. We provide experimental verification of that the atmospheric pressure sensor device has the characteristics of a simple structure, lack of an external power supply, automatic temperature compensation, and high sensitivity. The sensor system has good sensitivity, which can be up to 100 nm/MPa, and repeatability. In addition, the device exhibits desired hysteresis.

Viewing the functional consequences of traumatic brain injury by using brain SPECT.

PubMed

Pavel, D; Jobe, T; Devore-Best, S; Davis, G; Epstein, P; Sinha, S; Kohn, R; Craita, I; Liu, P; Chang, Y

2006-03-01

High-resolution brain SPECT is increasingly benefiting from improved image processing software and multiple complementary display capabilities. This enables detailed functional mapping of the disturbances in relative perfusion occurring after TBI. The patient population consisted of 26 cases (ages 8-61 years)between 3 months and 6 years after traumatic brain injury.A very strong case can be made for the routine use of Brain SPECT in TBI. Indeed it can provide a detailed evaluation of multiple functional consequences after TBI and is thus capable of supplementing the clinical evaluation and tailoring the therapeutic strategies needed. In so doing it also provides significant additional information beyond that available from MRI/CT. The critical factor for Brain SPECT's clinical relevance is a carefully designed technical protocol, including displays which should enable a comprehensive description of the patterns found, in a user friendly mode.

Soil and leaf litter metaproteomics—a brief guideline from sampling to understanding

PubMed Central

Keiblinger, Katharina M.; Fuchs, Stephan; Zechmeister-Boltenstern, Sophie; Riedel, Katharina

2016-01-01

The increasing application of soil metaproteomics is providing unprecedented, in-depth characterization of the composition and functionality of in situ microbial communities. Despite recent advances in high-resolution mass spectrometry, soil metaproteomics still suffers from a lack of effective and reproducible protein extraction protocols and standardized data analyses. This review discusses the opportunities and limitations of selected techniques in soil-, and leaf litter metaproteomics, and presents a step-by-step guideline on their application, covering sampling, sample preparation, extraction and data evaluation strategies. In addition, we present recent applications of soil metaproteomics and discuss how such approaches, linking phylogenetics and functionality, can help gain deeper insights into terrestrial microbial ecology. Finally, we strongly recommend that to maximize the insights environmental metaproteomics may provide, such methods should be employed within a holistic experimental approach considering relevant aboveground and belowground ecosystem parameters. PMID:27549116

A three-dimensional cathode matrix with bi-confinement effect of polysulfide for lithium-sulfur battery

NASA Astrophysics Data System (ADS)

Song, Ren-Sheng; Wang, Bo; Ruan, Ting-Ting; Wang, Lei; Luo, Hao; Wang, Fei; Gao, Tian-Tian; Wang, Dian-Long

2018-01-01

Soluble polysulfide shuttling is still the main cause of restricting the development of lithium-sulfur (Li-S) battery. Here, we propose a novel three-dimensional reduced graphene oxide@sulfur/nitrogen-doped porous carbon polyhedron/carbon nanotubes (rGO@S/NCP/CNTs) composite with bi-confinement effect of polysulfide as an effective cathode material. In rGO@S/NCP/CNTs, NCP provides physical confinement for sulfur and soluble polysulfide by its abundant micropores and mesopores, while oxygen functional groups of rGO provide strong chemical confinement to soluble polysulfide. Additionally, CNTs with one-dimensional conductivity enable facile transport of electrons. Therefore, the resulting rGO@S/NCP/CNTs composite shows an obvious enhancement in cycling performance for Li-S battery, and reversible capacities up to 738 mAh g-1 and 660 mAh g-1 over 100 and 200 cycles are remained at 0.2 C rate.

Measuring health care process quality with software quality measures.

PubMed

Yildiz, Ozkan; Demirörs, Onur

2012-01-01

Existing quality models focus on some specific diseases, clinics or clinical areas. Although they contain structure, process, or output type measures, there is no model which measures quality of health care processes comprehensively. In addition, due to the not measured overall process quality, hospitals cannot compare quality of processes internally and externally. To bring a solution to above problems, a new model is developed from software quality measures. We have adopted the ISO/IEC 9126 software quality standard for health care processes. Then, JCIAS (Joint Commission International Accreditation Standards for Hospitals) measurable elements were added to model scope for unifying functional requirements. Assessment (diagnosing) process measurement results are provided in this paper. After the application, it was concluded that the model determines weak and strong aspects of the processes, gives a more detailed picture for the process quality, and provides quantifiable information to hospitals to compare their processes with multiple organizations.

The NASA Lewis Research Center SBIR program: An assessment

NASA Technical Reports Server (NTRS)

Grimes, Hubert H.; Metzger, Marie E.; Kim, Walter S.

1993-01-01

An assessment was made of the NASA Lewis Small Business Innovation Research (SBIR) Program for the years 1983 to 1989. The assessment was based on the study of 99 Phase 1 contracts and 39 Phase 2 contracts. The overall impact of SBIR was found to be very positive, contributing strongly to many NASA programs. In addition, many successful efforts were commercialized benefiting the small business, federal agencies, and the aerospace industry. The program was evaluated in terms of contract quality, innovativeness, comparison to the state-of-the-art, achievement of goals, difficulty, and impact. Program difficulties were also identified, which could suggest possible program improvements. Much of the information gained in this assessment provided a basis for a SBIR data base which will be updated every year. This data base is computerized and will provide an excellent source of information about past SBIR efforts and company capabilities.

Progress toward Kelvin-Helmholtz instabilities in a High-Energy-Density Plasma on the Nike laser

NASA Astrophysics Data System (ADS)

Harding, E. C.; Drake, R. P.; Gillespie, R. S.; Grosskopf, M. J.; Huntington, C. M.; Aglitskiy, Y.; Weaver, J. L.; Velikovich, A. L.; Plewa, T.; Dwarkadas, V. V.

2008-04-01

In the realm of high-energy-density (HED) plasmas, there exist three primary hydrodynamic instabilities of concern: Rayleigh-Taylor (RT), Richtmyer-Meshkov (RM), and Kelvin-Helmholtz (KH). Although the RT and the RM instabilities have been readily observed and diagnosed in the laboratory, the KH instability remains relatively unexplored in HED plasmas. Unlike the RT and RM instabilities, the KH instability is driven by a lifting force generated by a strong velocity gradient in a stratified fluid. Understanding the KH instability mechanism in HED plasmas will provide essential insight into oblique shock systems, jets, mass stripping, and detailed RT-spike development. In addition, our KH experiment will help provide the groundwork for future transition to turbulence experiments. We present 2D FLASH simulations and experimental data from our initial attempts to create a pure KH system using the Nike laser at the Naval Research Laboratory.

A Bibliometric History of the Journal of Psychology Between 1936 and 2015.

PubMed

Tur-Porcar, Ana; Mas-Tur, Alicia; Merigó, José M; Roig-Tierno, Norat; Watt, John

2018-05-19

The Journal of Psychology: Interdisciplinary and Applied is a leading international journal in psychology dating back to 1935. This study examines its publications since its creation utilizing a bibliometric analysis. The primary objective is to provide a complete overview of the key factors affecting the journal. This analysis includes such key issues as the publication and citation structure of the journal, its most cited articles, and the leading authors, institutions, and countries referenced in the journal. The work uses the Scopus database to classify the bibliographic material. Additionally, the analysis provides a graphical mapping of the bibliographic data by using visualization of similarities viewer software. This software uses several bibliometric techniques including co-citation, bibliographic coupling and co-occurrence of keywords. The Journal of Psychology is strongly connected to most of the current leading journals in psychology, and currently has a 5-year impact factor of 1.77 (Thomson Reuters, 2015 Journal Citation Reports).

Nano-antenna in a photoconductive photomixer for highly efficient continuous wave terahertz emission

PubMed Central

Tanoto, H.; Teng, J. H.; Wu, Q. Y.; Sun, M.; Chen, Z. N.; Maier, S. A.; Wang, B.; Chum, C. C.; Si, G. Y.; Danner, A. J.; Chua, S. J.

2013-01-01

We report highly efficient continuous-wave terahertz (THz) photoconductive antenna based photomixer employing nano-gap electrodes in the active region. The tip-to-tip nano-gap electrode structure provides strong THz field enhancement and acts as a nano-antenna to radiate the THz wave generated in the active region of the photomixer. In addition, it provides good impedance matching to the THz planar antenna and exhibits a lower RC time constant, allowing more efficient radiation especially at the higher part of the THz spectrum. As a result, the output intensity of the photomixer with the new nano-gap electrode structure in the active region is two orders of magnitude higher than that of a photomixer with typical interdigitated electrodes. Significant improvement in the THz emission bandwidth was also observed. An efficient continuous wave THz source will greatly benefit compact THz system development for high resolution THz spectroscopy and imaging applications. PMID:24100840

Challenges of climate change: an Arctic perspective.

PubMed

Corell, Robert W

2006-06-01

Climate change is being experienced particularly intensely in the Arctic. Arctic average temperature has risen at almost twice the rate as that of the rest of the world in the past few decades. Widespread melting of glaciers and sea ice and rising permafrost temperatures present additional evidence of strong Arctic warming. These changes in the Arctic provide an early indication of the environmental and societal significance of global consequences. The Arctic also provides important natural resources to the rest of the world (such as oil, gas, and fish) that will be affected by climate change, and the melting of Arctic glaciers is one of the factors contributing to sea level rise around the globe. An acceleration of these climatic trends is projected to occur during this century, due to ongoing increases in concentrations of greenhouse gases in the Earth's atmosphere. These Arctic changes will, in turn, impact the planet as a whole.

Breast self-examination pamphlets: a content analysis grounded in fear appeal research.

PubMed

Kline, K N; Mattson, M

2000-01-01

In this study, we used the topic of breast self-examination (BSE) to illustrate how content analysis of promotional texts (already in existence, in the process of being created, or both) can provide supplementary data to that derived from audience analysis. Specifically, we used content analysis to isolate messages in BSE pamphlets that are consistent with the variables of severity, susceptibility, response efficacy, and self-efficacy, identified by existing fear appeal research and supported by other persuasion research as critical to the construction of effective health promotion messages. We then used statistical analyses to describe the relation among these 4 message variables. Our findings suggested that BSE pamphlets contain an unbalanced proportion of threat to efficacy arguments. Additionally, the efficacy messages were substantively weak. We contrasted these messages against the relatively strong mammography arguments contained in these pamphlets. We then provided recommendations for formulating stronger persuasive arguments in BSE promotional materials.

Electroweak baryogenesis from a dark sector

NASA Astrophysics Data System (ADS)

Cline, James M.; Kainulainen, Kimmo; Tucker-Smith, David

2017-06-01

Adding an extra singlet scalar S to the Higgs sector can provide a barrier at tree level between a false vacuum with restored electroweak symmetry and the true one. This has been demonstrated to readily give a strong phase transition as required for electroweak baryogenesis. We show that with the addition of a fermionic dark matter particle χ coupling to S , a simple UV-complete model can realize successful electroweak baryogenesis. The dark matter gets a C P asymmetry that is transferred to the standard model through a C P portal interaction, which we take to be a coupling of χ to τ leptons and an inert Higgs doublet. The C P asymmetry induced in left-handed τ leptons biases sphalerons to produce the baryon asymmetry. The model has promising discovery potential at the LHC, while robustly providing a large enough baryon asymmetry and correct dark matter relic density with reasonable values of the couplings.

Cesium iodide alloys

DOEpatents

Kim, H.E.; Moorhead, A.J.

1992-12-15

A transparent, strong CsI alloy is described having additions of monovalent iodides. Although the preferred iodide is AgI, RbI and CuI additions also contribute to an improved polycrystalline CsI alloy with outstanding multispectral infrared transmittance properties. 6 figs.

The Global Climate Anomaly in 1940-1942

NASA Astrophysics Data System (ADS)

Brönnimann, S.; Luterbacher, J.; Staehelin, J.; Svendby, T. M.

2003-12-01

An unprecedented climatic anomaly occurred in the tropics and in the Northern Hemisphere in 1940-1942. During a strong and prolonged El Niño [Bigg & Inoué, QJRMS 118 (1992), 125], extremely cold winters were observed in Europe, accompanied by very warm temperatures in Alaska and large parts of the Arctic and a cold North Pacific. The anomalies were strong (comprising the two coldest European winters of the 20th century) and extraordinarily persistent. In addition, exceptionally high values of total ozone are reported [Langlo, Geofys. Publ. 18/6 (1952)], pointing to an anomalous stratospheric circulation. Events of this magnitude have a strong economical and environmental impact; the 1940s anomaly even affected World War II. Studying this anomaly in detail contributes to (1) document the extent of 20th century climate variability, (2) understand large-scale coupling processes between the tropics and the extratropics and between the troposphere and the stratosphere and (3) develop tools to analyze past upper-level climate variability prior to 1948, i.e., the reanalysis period. For this study we have compiled, digitized, and re-evaluated several tens of thousands of temperature and pressure profiles from aircraft and radiosonde ascents up to 50 hPa [Brönnimann, Int. J. Clim. 23 (2003), 769]. The upper-air data were supplemented with data from the Earth's surface and used to statistically reconstruct monthly upper-level fields for the extratropical Northern Hemisphere up to 100 hPa [Brönnimann & Luterbacher, Clim. Dyn., submitted]. Although the quality of the reconstructed stratospheric fields is not comparable to more recent data, it is sufficient to allow a broad characterization of the circulation at 100 hPa during the early 1940s. In addition to upper-air data, several total ozone series from the 1940s were re-evaluated [Brönnimann et al., QJRMS 129 (2003), 2819], providing further information on the stratosphere. In this paper we present an analysis of these new data sets and compare the results to climate model data. It is demonstrated that the climate anomaly at the ground was accompanied in the lower stratosphere by a weak polar vortex and warm temperatures over the polar region, Eurasia, and the North Pacific. The total ozone data show a peak in 1940-1942 in all available records, at sites as far apart as China, North America, central Europe, and the Arctic. The co-occurrence of warm tropical SSTs (due to El Niño), a weak polar vortex and warm lower stratosphere over polar regions, and a total ozone increase is in agreement with findings by van Loon and Labitzke [Mon. Wea. Rev. 115 (1987), 357]. Using the 290-yr control run of the Community Climate System Model CCSM-2.0 provided by UCAR we show that such large-scale coupling events are related to an exceptionally large difference between tropical and northern-extratropical SSTs such as during strong El Niños. The coupling most likely proceeds through a change in planetary wave activity in the northern extratropics that manifests itself in a strong Aleutian low and a weak Icelandic low and in a disturbance of the polar vortex in the stratosphere. The 1940-1942 climate anomaly is not well known among scientists, but it is unprecedented in strength, yet exemplary in character, providing a unique opportunity to study large-scale climate variability.

Detailed observations of the source of terrestrial narrowband electromagnetic radiation

NASA Technical Reports Server (NTRS)

Kurth, W. S.

1982-01-01

Detailed observations are presented of a region near the terrestrial plasmapause where narrowband electromagnetic radiation (previously called escaping nonthermal continuum radiation) is being generated. These observations show a direct correspondence between the narrowband radio emissions and electron cyclotron harmonic waves near the upper hybrid resonance frequency. In addition, electromagnetic radiation propagating in the Z-mode is observed in the source region which provides an extremely accurate determination of the electron plasma frequency and, hence, density profile of the source region. The data strongly suggest that electrostatic waves and not Cerenkov radiation are the source of the banded radio emissions and define the coupling which must be described by any viable theory.

Life cycles of persistent anomalies. II - The development of persistent negative height anomalies over the North Pacific Ocean

NASA Technical Reports Server (NTRS)

Dole, Randall M.; Black, Robert X.

1990-01-01

Consideration is given to the potential sources for the development of cases defined by strong and persistent negative height anomalies over the central North Pacific. The analyses of Dole (1986) are extended by providing a more complete synoptic description of the developments and additional diagnostic analysis to identify dynamical mechanisms responsible for the developments. The synoptic characteristics of the developments are reviewed and the barotropic and baroclinic processes of the developments are analyzed. The reproducibility and representativeness of the results are examined. The observed characteristics suggest that the large-scale flow anomalies develop as a result of an instability of three-dimensional wintertime mean flow.

Decentralized Quasi-Newton Methods

NASA Astrophysics Data System (ADS)

Eisen, Mark; Mokhtari, Aryan; Ribeiro, Alejandro

2017-05-01

We introduce the decentralized Broyden-Fletcher-Goldfarb-Shanno (D-BFGS) method as a variation of the BFGS quasi-Newton method for solving decentralized optimization problems. The D-BFGS method is of interest in problems that are not well conditioned, making first order decentralized methods ineffective, and in which second order information is not readily available, making second order decentralized methods impossible. D-BFGS is a fully distributed algorithm in which nodes approximate curvature information of themselves and their neighbors through the satisfaction of a secant condition. We additionally provide a formulation of the algorithm in asynchronous settings. Convergence of D-BFGS is established formally in both the synchronous and asynchronous settings and strong performance advantages relative to first order methods are shown numerically.

NMR relaxometry study of cement hydration in the presence of different oxidic fine fraction materials.

PubMed

Nestle, Nikolaus

2004-01-01

NMR relaxometry has been applied to study hydrating cements for about 25 years now. The most important advantage over other experimental approaches is the possibility to conduct non-destructive measurements with a time resolution of minutes. NMR relaxometry data thus can help to identify details in the time course of cement hydration that possibly would be overlooked in other experiments with lower temporal resolution. Time-resolved information on cement hydration kinetics can provide interesting insights into the impact of oxidic additive materials on cement hydration. For PbO, a very strong delay was observed which then was systematically studied. An explanation for this delay is suggested.

Federal tax-exemption requirements for joint ventures between nonprofit hospital providers and for-profit entities: form over substance?

PubMed

Young, Gary J

2004-01-01

This article discusses the IRS rule on hospital joint ventures and related legal developments. The central thesis is that the IRS's emphasis on operational control is misplaced from both a legal and a policy perspective, and reflects a decidedly strong preference for the form of a joint venture's governance over the substance of its charitable and community service activities. More specifically, the article challenges the IRS position that the rule is a corollary of existing tax law principles. Additionally, social science research is presented to demonstrate that the rule is not likely to promote, and may in fact undermine, United States health policy objectives.

Incentives for knowledge sharing: impact of organisational culture and information technology

NASA Astrophysics Data System (ADS)

Lyu, Hongbo; Zhang, Zuopeng Justin

2017-10-01

This research presents and examines an analytical model of knowledge management in which organisational culture dynamically improves with knowledge-sharing and learning activities within organisations. We investigate the effects of organisational incentives and the level of information technology on the motivation of knowledge sharing. We derive a linear incentive reward structure for knowledge sharing under both homogeneous and heterogeneous conditions. In addition, we show how the organisational culture and the optimum linear sharing reward change with several crucial factors, and summarise three sets of methods (strong IT support, congruent organisational culture, and effective employee assessment) to complement the best linear incentive. Our research provides valuable insights for practitioners in terms of implementing knowledge-management initiatives.

Strong Cosserat Elasticity in a Transversely Isotropic Polymer Lattice

NASA Astrophysics Data System (ADS)

Rueger, Z.; Lakes, R. S.

2018-02-01

Large size effects are experimentally measured in lattices of triangular unit cells: about a factor of 36 in torsion rigidity and 29 in bending rigidity. This nonclassical phenomenon is consistent with Cosserat elasticity, which allows for the rotation of points and distributed moments in addition to the translation of points and force stress of classical elasticity. The Cosserat characteristic length for torsion is ℓt=9.4 mm ; for bending, it is ℓb=8.8 mm ; these values are comparable to the cell size. Nonclassical effects are much stronger than in stretch-dominated lattices with uniform straight ribs. The lattice structure provides a path to the attainment of arbitrarily large effects.

Two-point motional Stark effect diagnostic for Madison Symmetric Torus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ko, J.; Den Hartog, D. J.; Caspary, K. J.

2010-10-15

A high-precision spectral motional Stark effect (MSE) diagnostic provides internal magnetic field measurements for Madison Symmetric Torus (MST) plasmas. Currently, MST uses two spatial views - on the magnetic axis and on the midminor (off-axis) radius, the latter added recently. A new analysis scheme has been developed to infer both the pitch angle and the magnitude of the magnetic field from MSE spectra. Systematic errors are reduced by using atomic data from atomic data and analysis structure in the fit. Reconstructed current density and safety factor profiles are more strongly and globally constrained with the addition of the off-axis radiusmore » measurement than with the on-axis one only.« less

Interaction of proflavine with DNA studied by colloid surface enhanced resonance Raman spectroscopy

NASA Astrophysics Data System (ADS)

Koglin, E.; Séquaris, J.-M.

1986-03-01

The interaction of the mutagenic highly fluourescing proflavine (3,6-diaminoacridine: PF) dye with calf thymus DNA has been studied by Surface Enhanced Resonance Raman Scattering (SERRS). Since the Ag-colloids almost completely quenche the strong fluorescence it is possible to obtain excellent vibrational spectra in a wide frequency range providing valuable information about the intercalation. The intercalation does not affect the vibrational frequencies of the proflavine dye. On the other hand, intensity changes are observed in some of the ring- and NH 2-modes of proflavine upon intercalation. This Raman hypochromism is characteristic for ring stacking interactions and in the SERRS spetroscopy for an additional effects of the dye orientation to the surface.

The Environmental Management Project Manager`s Handbook for improved project definition

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-02-01

The United States Department of Energy (DOE) is committed to providing high quality products that satisfy customer needs and are the associated with this goal, DOE personnel must possess the knowledge, skills, and abilities to ensure successful job performance. In addition, there must be recognition that the greatest obstacle to proper project performance is inadequate project definition. Without strong project definition, DOE environmental management efforts are vulnerable to fragmented solutions, duplication of effort, and wastes resources. The primary means of ensuring environmental management projects meet cost and schedule milestones is through a structured and graded approach to project definition, whichmore » is the focus of this handbook.« less

Catalytic processes in the atmospheres of earth and Venus

NASA Technical Reports Server (NTRS)

Demore, W. B.; Yung, Y. L.

1982-01-01

Photochemical processes in planetary atmospheres are strongly influenced by catalytic effects of minor constituents. Catalytic cycles in the atmospheres of Earth and Venus are closely related. For example, chlorine oxides (ClOx) act as catalysts in the two atmospheres. On earth, they serve to convert odd oxygen (atomic oxygen and ozone) to molecular oxygen. On Venus they have a similar effect, but in addition they accelerate the reactions of atomic and molecular oxygen with carbon monoxide. The latter process occurs by a unique combination of ClOx catalysis and sulful dioxide photosensitization. The mechanism provides an explanation for the very low extent of carbon dioxide decomposition by sunlight in the Venus atmosphere.

Evaluation of the non-Gaussianity of two-mode entangled states over a bosonic memory channel via cumulant theory and quadrature detection

NASA Astrophysics Data System (ADS)

Xiang, Shao-Hua; Wen, Wei; Zhao, Yu-Jing; Song, Ke-Hui

2018-04-01

We study the properties of the cumulants of multimode boson operators and introduce the phase-averaged quadrature cumulants as the measure of the non-Gaussianity of multimode quantum states. Using this measure, we investigate the non-Gaussianity of two classes of two-mode non-Gaussian states: photon-number entangled states and entangled coherent states traveling in a bosonic memory quantum channel. We show that such a channel can skew the distribution of two-mode quadrature variables, giving rise to a strongly non-Gaussian correlation. In addition, we provide a criterion to determine whether the distributions of these states are super- or sub-Gaussian.

MRO's High Resolution Imaging Science Experiment (HiRISE): Education and Public Outreach Plans

NASA Technical Reports Server (NTRS)

Gulick, V.; McEwen, A.; Delamere, W. A.; Eliason, E.; Grant, J.; Hansen, C.; Herkenhoff, K.; Keszthelyi, L.; Kirk, R.; Mellon, M.

2003-01-01

The High Resolution Imaging Experiment, described by McEwen et al. and Delamere et al., will fly on the Mars 2005 Orbiter. In conjunction with the NASA Mars E/PO program, the HiRISE team plans an innovative and aggressive E/PO effort to complement the unique high-resolution capabilities of the camera. The team is organizing partnerships with existing educational outreach programs and museums and plans to develop its own educational materials. In addition to other traditional E/PO activities and a strong web presence, opportunities will be provided for the public to participate in image targeting and science analysis. The main aspects of our program are summarized.

Clinical lesson: eosinophilic oesophagitis, a new diagnosis to swallow

PubMed Central

Lamb, C A; Kanakala, V; Stirling, R W; Attwood, S E A

2010-01-01

Eosinophilic oesophagitis (EoE) is a recently described condition that has gained increasing recognition over the past 5 years. Despite this, many clinicians remain unaware of EoE, often leading to diagnostic delay and therefore significant morbidity. The diagnosis of EoE should be considered in any patient with a history of intermittent or continuous dysphagia, or oesophageal food impaction. It should be strongly suspected in young patients, particularly men, presenting with dysphagia and a history of atopy. Here, three patients are presented that highlight common features of EoE. In addition, a clinical review of the worldwide literature is provided to heighten physician awareness and understanding of the condition. PMID:28839538

Evidence for impact ionization in vanadium dioxide

DOE PAGES

Holleman, Joshua; Bishop, Michael M.; Garcia, Carlos; ...

2016-10-17

Pump-probe optical spectroscopy was used to investigate charge carrier multiplication via impact ionization in the M 1 insulating phase of VO 2. By comparing the transient reflectivities of the film when pumped at less than and then more than twice the band-gap energy, we observed an enhancement of the ultrafast response with the higher energy pump color while the film was still transiently in the insulating phase. We additionally identified multiple timescales within the charge dynamics and analyzed how these changed when the pump and probe wavelengths were varied. This experiment provided evidence that impact ionization acts efficiently as amore » carrier multiplication process in this prototypical strongly-correlated insulator.« less

Influence of a MoOx interlayer on the open-circuit voltage in organic photovoltaic cells

NASA Astrophysics Data System (ADS)

Zou, Yunlong; Holmes, Russell J.

2013-07-01

Metal-oxides have been used as interlayers at the anode-organic interface in organic photovoltaic cells (OPVs) to increase the open-circuit voltage (VOC). We examine the role of MoOx in determining the maximum VOC in a planar heterojunction OPV and find that the interlayer strongly affects the temperature dependence of VOC. Boron subphthalocyanine chloride (SubPc)-C60 OPVs that contain no interlayer show a maximum VOC of 1.2 V at low temperature, while those with MoOx show no saturation, reaching VOC > 1.4 V. We propose that the MoOx-SubPc interface forms a Schottky junction that provides an additional contribution to VOC at low temperature.

Numerically robust and efficient nonlocal electron transport in 2D DRACO simulations

NASA Astrophysics Data System (ADS)

Cao, Duc; Chenhall, Jeff; Moses, Greg; Delettrez, Jacques; Collins, Tim

2013-10-01

An improved implicit algorithm based on Schurtz, Nicolai and Busquet (SNB) algorithm for nonlocal electron transport is presented. Validation with direct drive shock timing experiments and verification with the Goncharov nonlocal model in 1D LILAC simulations demonstrate the viability of this efficient algorithm for producing 2D lagrangian radiation hydrodynamics direct drive simulations. Additionally, simulations provide strong incentive to further modify key parameters within the SNB theory, namely the ``mean free path.'' An example 2D polar drive simulation to study 2D effects of the nonlocal flux as well as mean free path modifications will also be presented. This research was supported by the University of Rochester Laboratory for Laser Energetics.

Genetic insights into the mechanisms of Fgf signaling

PubMed Central

Brewer, J. Richard; Mazot, Pierre; Soriano, Philippe

2016-01-01

The fibroblast growth factor (Fgf) family of ligands and receptor tyrosine kinases is required throughout embryonic and postnatal development and also regulates multiple homeostatic functions in the adult. Aberrant Fgf signaling causes many congenital disorders and underlies multiple forms of cancer. Understanding the mechanisms that govern Fgf signaling is therefore important to appreciate many aspects of Fgf biology and disease. Here we review the mechanisms of Fgf signaling by focusing on genetic strategies that enable in vivo analysis. These studies support an important role for Erk1/2 as a mediator of Fgf signaling in many biological processes but have also provided strong evidence for additional signaling pathways in transmitting Fgf signaling in vivo. PMID:27036966

Key Process Uncertainties in Soil Carbon Dynamics: Comparing Multiple Model Structures and Observational Meta-analysis

NASA Astrophysics Data System (ADS)

Sulman, B. N.; Moore, J.; Averill, C.; Abramoff, R. Z.; Bradford, M.; Classen, A. T.; Hartman, M. D.; Kivlin, S. N.; Luo, Y.; Mayes, M. A.; Morrison, E. W.; Riley, W. J.; Salazar, A.; Schimel, J.; Sridhar, B.; Tang, J.; Wang, G.; Wieder, W. R.

2016-12-01

Soil carbon (C) dynamics are crucial to understanding and predicting C cycle responses to global change and soil C modeling is a key tool for understanding these dynamics. While first order model structures have historically dominated this area, a recent proliferation of alternative model structures representing different assumptions about microbial activity and mineral protection is providing new opportunities to explore process uncertainties related to soil C dynamics. We conducted idealized simulations of soil C responses to warming and litter addition using models from five research groups that incorporated different sets of assumptions about processes governing soil C decomposition and stabilization. We conducted a meta-analysis of published warming and C addition experiments for comparison with simulations. Assumptions related to mineral protection and microbial dynamics drove strong differences among models. In response to C additions, some models predicted long-term C accumulation while others predicted transient increases that were counteracted by accelerating decomposition. In experimental manipulations, doubling litter addition did not change soil C stocks in studies spanning as long as two decades. This result agreed with simulations from models with strong microbial growth responses and limited mineral sorption capacity. In observations, warming initially drove soil C loss via increased CO2 production, but in some studies soil C rebounded and increased over decadal time scales. In contrast, all models predicted sustained C losses under warming. The disagreement with experimental results could be explained by physiological or community-level acclimation, or by warming-related changes in plant growth. In addition to the role of microbial activity, assumptions related to mineral sorption and protected C played a key role in driving long-term model responses. In general, simulations were similar in their initial responses to perturbations but diverged over decadal time scales. This suggests that more long-term soil experiments may be necessary to resolve important process uncertainties related to soil C storage. We also suggest future experiments examine how microbial activity responds to warming under a range of soil clay contents and in concert with changes in litter inputs.

Genetics of Adverse Reactions to Haloperidol in a Mouse Diallel: A Drug–Placebo Experiment and Bayesian Causal Analysis

PubMed Central

Crowley, James J.; Kim, Yunjung; Lenarcic, Alan B.; Quackenbush, Corey R.; Barrick, Cordelia J.; Adkins, Daniel E.; Shaw, Ginger S.; Miller, Darla R.; de Villena, Fernando Pardo-Manuel; Sullivan, Patrick F.; Valdar, William

2014-01-01

Haloperidol is an efficacious antipsychotic drug that has serious, unpredictable motor side effects that limit its utility and cause noncompliance in many patients. Using a drug–placebo diallel of the eight founder strains of the Collaborative Cross and their F1 hybrids, we characterized aggregate effects of genetics, sex, parent of origin, and their combinations on haloperidol response. Treating matched pairs of both sexes with drug or placebo, we measured changes in the following: open field activity, inclined screen rigidity, orofacial movements, prepulse inhibition of the acoustic startle response, plasma and brain drug level measurements, and body weight. To understand the genetic architecture of haloperidol response we introduce new statistical methodology linking heritable variation with causal effect of drug treatment. Our new estimators, “difference of models” and “multiple-impute matched pairs”, are motivated by the Neyman–Rubin potential outcomes framework and extend our existing Bayesian hierarchical model for the diallel (Lenarcic et al. 2012). Drug-induced rigidity after chronic treatment was affected by mainly additive genetics and parent-of-origin effects (accounting for 28% and 14.8% of the variance), with NZO/HILtJ and 129S1/SvlmJ contributions tending to increase this side effect. Locomotor activity after acute treatment, by contrast, was more affected by strain-specific inbreeding (12.8%). In addition to drug response phenotypes, we examined diallel effects on behavior before treatment and found not only effects of additive genetics (10.2–53.2%) but also strong effects of epistasis (10.64–25.2%). In particular: prepulse inhibition showed additivity and epistasis in about equal proportions (26.1% and 23.7%); there was evidence of nonreciprocal epistasis in pretreatment activity and rigidity; and we estimated a range of effects on body weight that replicate those found in our previous work. Our results provide the first quantitative description of the genetic architecture of haloperidol response in mice and indicate that additive, dominance-like inbreeding and parent-of-origin effects contribute strongly to treatment effect heterogeneity for this drug. PMID:24240528

The Psychological Characteristics of Experiences That Influence Science Motivation and Content Knowledge

ERIC Educational Resources Information Center

Bathgate, Meghan; Schunn, Christian

2017-01-01

While motivational changes towards science are common during adolescence, our work asks which perceived classroom experiences are most strongly related to these changes. Additionally, we examine which experiences are most strongly associated with learning classroom content. In particular, using self-reports from a sample of approximately 3000…

Chokka-Chaffa' Kilimpi', Chikashshiyaakni' Kilimpi': Strong Family, Strong Nation

ERIC Educational Resources Information Center

Deacon, Zermarie; Pendley, Joy; Hinson, Waymon R.; Hinson, Joshua D.

2011-01-01

To encourage the health and well-being of American Indian (AI) communities, it is first necessary to understand the meaning of health for particular tribes. As such, this investigation reports on the meaning of health and well-being for Chickasaw families. Findings from this investigation additionally highlight ways in which characteristics of…

ANZA Seismic Network- From Monitoring to Science

NASA Astrophysics Data System (ADS)

Vernon, F.; Eakin, J.; Martynov, V.; Newman, R.; Offield, G.; Hindley, A.; Astiz, L.

2007-05-01

The ANZA Seismic Network (http:eqinfo.ucsd.edu) utilizes broadband and strong motion sensors with 24-bit dataloggers combined with real-time telemetry to monitor local and regional seismicity in southernmost California. The ANZA network provides real-time data to the IRIS DMC, California Integrated Seismic Network (CISN), other regional networks, and the Advanced National Seismic System (ANSS), in addition to providing near real-time information and monitoring to the greater San Diego community. Twelve high dynamic range broadband and strong motion sensors adjacent to the San Jacinto Fault zone contribute data for earthquake source studies and continue the monitoring of the seismic activity of the San Jacinto fault initiated 24 years ago. Five additional stations are located in the San Diego region with one more station on San Clemente Island. The ANZA network uses the advance wireless networking capabilities of the NSF High Performance Wireless Research and Education Network (http:hpwren.ucsd.edu) to provide the communication infrastructure for the real-time telemetry of Anza seismic stations. The ANZA network uses the Antelope data acquisition software. The combination of high quality hardware, communications, and software allow for an annual network uptime in excess of 99.5% with a median annual station real-time data return rate of 99.3%. Approximately 90,000 events, dominantly local sources but including regional and teleseismic events, comprise the ANZA network waveform database. All waveform data and event data are managed using the Datascope relational database. The ANZA network data has been used in a variety of scientific research including detailed structure of the San Jacinto Fault Zone, earthquake source physics, spatial and temporal studies of aftershocks, array studies of teleseismic body waves, and array studies on the source of microseisms. To augment the location, detection, and high frequency observations of the seismic source spectrum from local earthquakes, the ANZA network is receiving real-time data from borehole arrays located at the UCSD Thornton Hospital, and from UCSB's Borrego Valley and Garner Valley Downhole Arrays. Finally the ANZA network is acquiring data from seven PBO sites each with 300 meter deep MEMs accelerometers, passive seismometers, and a borehole strainmeter.

Molecular signatures for the phylum Synergistetes and some of its subclades.

PubMed

Bhandari, Vaibhav; Gupta, Radhey S

2012-11-01

Species belonging to the phylum Synergistetes are poorly characterized. Though the known species display Gram-negative characteristics and the ability to ferment amino acids, no single characteristic is known which can define this group. For eight Synergistetes species, complete genome sequences or draft genomes have become available. We have used these genomes to construct detailed phylogenetic trees for the Synergistetes species and carried out comprehensive analysis to identify molecular markers consisting of conserved signature indels (CSIs) in protein sequences that are specific for either all Synergistetes or some of their sub-groups. We report here identification of 32 CSIs in widely distributed proteins such as RpoB, RpoC, UvrD, GyrA, PolA, PolC, MraW, NadD, PyrE, RpsA, RpsH, FtsA, RadA, etc., including a large >300 aa insert within the RpoC protein, that are present in various Synergistetes species, but except for isolated bacteria, these CSIs are not found in the protein homologues from any other organisms. These CSIs provide novel molecular markers that distinguish the species of the phylum Synergistetes from all other bacteria. The large numbers of other CSIs discovered in this work provide valuable information that supports and consolidates evolutionary relationships amongst the sequenced Synergistetes species. Of these CSIs, seven are specifically present in Jonquetella, Pyramidobacter and Dethiosulfovibrio species indicating a cladal relationship among them, which is also strongly supported by phylogenetic trees. A further 15 CSIs that are only present in Jonquetella and Pyramidobacter indicate a close association between these two species. Additionally, a previously described phylogenetic relationship between the Aminomonas and Thermanaerovibrio species was also supported by 9 CSIs. The strong relationships indicated by the indel analysis provide incentives for the grouping of species from these clades into higher taxonomic groups such as families or orders. The identified molecular markers, due to their specificity for Synergistetes and presence in highly conserved regions of important proteins suggest novel targets for evolutionary, genetic and biochemical studies on these bacteria as well as for the identification of additional species belonging to this phylum in different environments.

Examination Of A Strong Downslope Warming Wind Event Over The Larsen Ice Shelf In Antarctica Through Modeling And Aircraft Observations

NASA Astrophysics Data System (ADS)

Grosvenor, D. P.; Choularton, T. W.; Gallagher, M. W.; Lachlan-Cope, T. A.; King, J. C.

2009-12-01

The high mountains of the Antarctic Peninsula (AP) provide a climatic barrier between the west and east. The east side is generally blocked from the warmer oceanic air of the west and is consequently usually under the influence of colder continental air. On occasion, however, air from the west can cross the barrier in the form of strong winds travelling down the eastern slopes, which are also very warm and dry due to adiabatic descent. They penetrate onto the Larsen ice shelves where they lead to above zero surface temperatures and are therefore likely to encourage surface melting. Crevasse propagation due to the weight of accumulated meltwater is currently thought to have been the major factor in causing the near total disintegration of the Larsen B ice shelf in 2002. In January 2006 the British Antarctic Survey performed an aircraft flight over the Larsen C ice shelf on the east side of the AP, which sampled a strong downslope wind event. Surface flux measurements over the ice shelf suggest that the sensible heat provided by the warm jets would be likely to be negated by latent heat losses from ice ablation. The main cause of any ice melting was likely to be due to shortwave radiation input. However, the warming from the jets is still likely to be important by acting as an on/off control for melting by keeping air temperatures above zero. In addition, the dryness of the winds is likely to prevent cloud cover and thus maximize exposure of the ice shelf to solar energy input. This case study has been modeled using the WRF mesoscale model. The model reproduces the strong downslope winds seen by the aircraft with good comparisons of wind speed and temperature profiles through the wind jets. Further comparisons to surface station data have allowed progress towards achieving the best set up of the model for this case. The modeling agrees with the results of the aircraft study in suggesting that solar radiation input is likely to provide the largest amount of energy for melting of the ice surface. The modeling provides insight into the physics of the downslope winds. They are driven by descent of air from above the mountain. This mechanism is different from that often perceived to occur in the AP region, whereby air from below the mountain crest rises over the obstacle and descends on the lee side. In the latter case, stronger cross-mountain winds lead to a greater likelihood of strong downslope winds. Instead, the situation is one where hydraulic flow over the mountain seems to occur as a symptom of both a low level inversion and gravity wave breaking higher up. These create critical layers so that the fluid depth at the mountain crest is tuned to the wavelength of the gravity waves resulting in the downslope winds. The wavelength depends on wind speed and atmospheric stability. Thus stronger cross mountain winds may not necessarily lead to strong downslope winds, since the wavelength may then be detuned to the fluid depth at the mountain crest.

Moral Bargain Hunters Purchase Moral Righteousness When it is Cheap: Within-Individual Effect of Stake Size in Economic Games

PubMed Central

Yamagishi, Toshio; Li, Yang; Matsumoto, Yoshie; Kiyonari, Toko

2016-01-01

Despite the repeatedly raised criticism that findings in economic games are specific to situations involving trivial incentives, most studies that have examined the stake-size effect have failed to find a strong effect. Using three prisoner’s dilemma experiments, involving 479 non-student residents of suburban Tokyo and 162 students, we show here that stake size strongly affects a player’s cooperation choices in prisoner’s dilemma games when stake size is manipulated within each individual such that each player faces different stake sizes. Participants cooperated at a higher rate when stakes were lower than when they were higher, regardless of the absolute stake size. These findings suggest that participants were ‘moral bargain hunters’ who purchased moral righteousness at a low price when they were provided with a ‘price list’ of prosocial behaviours. In addition, the moral bargain hunters who cooperated at a lower stake but not at a higher stake did not cooperate in a single-stake one-shot game. PMID:27296466

The Feedback-Related Negativity and the P300 Brain Potential Are Sensitive to Price Expectation Violations in a Virtual Shopping Task.

PubMed

Schaefer, Alexandre; Buratto, Luciano G; Goto, Nobuhiko; Brotherhood, Emilie V

A large body of evidence shows that buying behaviour is strongly determined by consumers' price expectations and the extent to which real prices violate these expectations. Despite the importance of this phenomenon, little is known regarding its neural mechanisms. Here we show that two patterns of electrical brain activity known to index prediction errors-the Feedback-Related Negativity (FRN) and the feedback-related P300 -were sensitive to price offers that were cheaper than participants' expectations. In addition, we also found that FRN amplitude time-locked to price offers predicted whether a product would be subsequently purchased or not, and further analyses suggest that this result was driven by the sensitivity of the FRN to positive price expectation violations. This finding strongly suggests that ensembles of neurons coding positive prediction errors play a critical role in real-life consumer behaviour. Further, these findings indicate that theoretical models based on the notion of prediction error, such as the Reinforcement Learning Theory, can provide a neurobiologically grounded account of consumer behavior.

STRONG ORACLE OPTIMALITY OF FOLDED CONCAVE PENALIZED ESTIMATION.

PubMed

Fan, Jianqing; Xue, Lingzhou; Zou, Hui

2014-06-01

Folded concave penalization methods have been shown to enjoy the strong oracle property for high-dimensional sparse estimation. However, a folded concave penalization problem usually has multiple local solutions and the oracle property is established only for one of the unknown local solutions. A challenging fundamental issue still remains that it is not clear whether the local optimum computed by a given optimization algorithm possesses those nice theoretical properties. To close this important theoretical gap in over a decade, we provide a unified theory to show explicitly how to obtain the oracle solution via the local linear approximation algorithm. For a folded concave penalized estimation problem, we show that as long as the problem is localizable and the oracle estimator is well behaved, we can obtain the oracle estimator by using the one-step local linear approximation. In addition, once the oracle estimator is obtained, the local linear approximation algorithm converges, namely it produces the same estimator in the next iteration. The general theory is demonstrated by using four classical sparse estimation problems, i.e., sparse linear regression, sparse logistic regression, sparse precision matrix estimation and sparse quantile regression.

Mental Imagery and Visual Working Memory

PubMed Central

Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage. PMID:22195024

Mental imagery and visual working memory.

PubMed

Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.

Memristive crypto primitive for building highly secure physical unclonable functions

NASA Astrophysics Data System (ADS)

Gao, Yansong; Ranasinghe, Damith C.; Al-Sarawi, Said F.; Kavehei, Omid; Abbott, Derek

2015-08-01

Physical unclonable functions (PUFs) exploit the intrinsic complexity and irreproducibility of physical systems to generate secret information. The advantage is that PUFs have the potential to provide fundamentally higher security than traditional cryptographic methods by preventing the cloning of devices and the extraction of secret keys. Most PUF designs focus on exploiting process variations in Complementary Metal Oxide Semiconductor (CMOS) technology. In recent years, progress in nanoelectronic devices such as memristors has demonstrated the prevalence of process variations in scaling electronics down to the nano region. In this paper, we exploit the extremely large information density available in nanocrossbar architectures and the significant resistance variations of memristors to develop an on-chip memristive device based strong PUF (mrSPUF). Our novel architecture demonstrates desirable characteristics of PUFs, including uniqueness, reliability, and large number of challenge-response pairs (CRPs) and desirable characteristics of strong PUFs. More significantly, in contrast to most existing PUFs, our PUF can act as a reconfigurable PUF (rPUF) without additional hardware and is of benefit to applications needing revocation or update of secure key information.

Infrared singularities in Landau gauge Yang-Mills theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alkofer, Reinhard; Huber, Markus Q.; Schwenzer, Kai

2010-05-15

We present a more detailed picture of the infrared regime of Landau-gauge Yang-Mills theory. This is done within a novel framework that allows one to take into account the influence of finite scales within an infrared power counting analysis. We find that there are two qualitatively different infrared fixed points of the full system of Dyson-Schwinger equations. The first extends the known scaling solution, where the ghost dynamics is dominant and gluon propagation is strongly suppressed. It features in addition to the strong divergences of gluonic vertex functions in the previously considered uniform scaling limit, when all external momenta tendmore » to zero, also weaker kinematic divergences, when only some of the external momenta vanish. The second solution represents the recently proposed decoupling scenario where the gluons become massive and the ghosts remain bare. In this case we find that none of the vertex functions is enhanced, so that the infrared dynamics is entirely suppressed. Our analysis also provides a strict argument why the Landau-gauge gluon dressing function cannot be infrared divergent.« less

Investigating the Relationship between Ocean Surface Currents and Seasonal Precipitation in the Western United States

NASA Astrophysics Data System (ADS)

Chiang, F.; AghaKouchak, A.

2017-12-01

While many studies have explored the predictive capabilities of teleconnections associated with North American climate, currently established teleconnections offer limited predictability for rainfall in the Western United States. A recent example was the 2015-16 California drought in which a strong ENSO signal did not lead to above average precipitation as was expected. From an exploration of climate and ocean variables available from satellite data, we hypothesize that ocean currents can provide additional information to explain precipitation variability and improve seasonal predictability on the West Coast. Since ocean currents are influenced by surface wind and temperatures, characterizing connections between currents and precipitation patterns has the potential to further our understanding of coastal weather patterns. For the study, we generated gridded point correlation maps to identify ocean areas with high correlation to precipitation time series corresponding to climate regions in the West Coast region. We also used other statistical measures to evaluate ocean `hot spot' regions with significant correlation to West Coast precipitation. Preliminary results show that strong correlations can be found in the tropical regions of the globe.

Memristive crypto primitive for building highly secure physical unclonable functions.

PubMed

Gao, Yansong; Ranasinghe, Damith C; Al-Sarawi, Said F; Kavehei, Omid; Abbott, Derek

2015-08-04

Physical unclonable functions (PUFs) exploit the intrinsic complexity and irreproducibility of physical systems to generate secret information. The advantage is that PUFs have the potential to provide fundamentally higher security than traditional cryptographic methods by preventing the cloning of devices and the extraction of secret keys. Most PUF designs focus on exploiting process variations in Complementary Metal Oxide Semiconductor (CMOS) technology. In recent years, progress in nanoelectronic devices such as memristors has demonstrated the prevalence of process variations in scaling electronics down to the nano region. In this paper, we exploit the extremely large information density available in nanocrossbar architectures and the significant resistance variations of memristors to develop an on-chip memristive device based strong PUF (mrSPUF). Our novel architecture demonstrates desirable characteristics of PUFs, including uniqueness, reliability, and large number of challenge-response pairs (CRPs) and desirable characteristics of strong PUFs. More significantly, in contrast to most existing PUFs, our PUF can act as a reconfigurable PUF (rPUF) without additional hardware and is of benefit to applications needing revocation or update of secure key information.

Memristive crypto primitive for building highly secure physical unclonable functions

PubMed Central

Gao, Yansong; Ranasinghe, Damith C.; Al-Sarawi, Said F.; Kavehei, Omid; Abbott, Derek

2015-01-01

Physical unclonable functions (PUFs) exploit the intrinsic complexity and irreproducibility of physical systems to generate secret information. The advantage is that PUFs have the potential to provide fundamentally higher security than traditional cryptographic methods by preventing the cloning of devices and the extraction of secret keys. Most PUF designs focus on exploiting process variations in Complementary Metal Oxide Semiconductor (CMOS) technology. In recent years, progress in nanoelectronic devices such as memristors has demonstrated the prevalence of process variations in scaling electronics down to the nano region. In this paper, we exploit the extremely large information density available in nanocrossbar architectures and the significant resistance variations of memristors to develop an on-chip memristive device based strong PUF (mrSPUF). Our novel architecture demonstrates desirable characteristics of PUFs, including uniqueness, reliability, and large number of challenge-response pairs (CRPs) and desirable characteristics of strong PUFs. More significantly, in contrast to most existing PUFs, our PUF can act as a reconfigurable PUF (rPUF) without additional hardware and is of benefit to applications needing revocation or update of secure key information. PMID:26239669

STRONG ORACLE OPTIMALITY OF FOLDED CONCAVE PENALIZED ESTIMATION

PubMed Central

Fan, Jianqing; Xue, Lingzhou; Zou, Hui

2014-01-01

Folded concave penalization methods have been shown to enjoy the strong oracle property for high-dimensional sparse estimation. However, a folded concave penalization problem usually has multiple local solutions and the oracle property is established only for one of the unknown local solutions. A challenging fundamental issue still remains that it is not clear whether the local optimum computed by a given optimization algorithm possesses those nice theoretical properties. To close this important theoretical gap in over a decade, we provide a unified theory to show explicitly how to obtain the oracle solution via the local linear approximation algorithm. For a folded concave penalized estimation problem, we show that as long as the problem is localizable and the oracle estimator is well behaved, we can obtain the oracle estimator by using the one-step local linear approximation. In addition, once the oracle estimator is obtained, the local linear approximation algorithm converges, namely it produces the same estimator in the next iteration. The general theory is demonstrated by using four classical sparse estimation problems, i.e., sparse linear regression, sparse logistic regression, sparse precision matrix estimation and sparse quantile regression. PMID:25598560

The Feedback-Related Negativity and the P300 Brain Potential Are Sensitive to Price Expectation Violations in a Virtual Shopping Task

PubMed Central

Schaefer, Alexandre; Buratto, Luciano G.; Goto, Nobuhiko; Brotherhood, Emilie V.

2016-01-01

A large body of evidence shows that buying behaviour is strongly determined by consumers’ price expectations and the extent to which real prices violate these expectations. Despite the importance of this phenomenon, little is known regarding its neural mechanisms. Here we show that two patterns of electrical brain activity known to index prediction errors–the Feedback-Related Negativity (FRN) and the feedback-related P300 –were sensitive to price offers that were cheaper than participants’ expectations. In addition, we also found that FRN amplitude time-locked to price offers predicted whether a product would be subsequently purchased or not, and further analyses suggest that this result was driven by the sensitivity of the FRN to positive price expectation violations. This finding strongly suggests that ensembles of neurons coding positive prediction errors play a critical role in real-life consumer behaviour. Further, these findings indicate that theoretical models based on the notion of prediction error, such as the Reinforcement Learning Theory, can provide a neurobiologically grounded account of consumer behavior. PMID:27658301

New Insights into the Puzzling P-Cygni Profiles of Magnetic Massive Stars

NASA Astrophysics Data System (ADS)

Erba, Christiana; David-Uraz, Alexandre; Petit, Véronique; Owocki, Stanley P.

2017-11-01

Magnetic massive stars comprise approximately 10% of the total OB star population. Modern spectropolarimetry shows these stars host strong, stable, large-scale, often nearly dipolar surface magnetic fields of 1 kG or more. These global magnetic fields trap and deflect outflowing stellar wind material, forming an anisotropic magnetosphere that can be probed with wind-sensitive UV resonance lines. Recent HST UV spectra of NGC 1624-2, the most magnetic O star observed to date, show atypically unsaturated P-Cygni profiles in the Civ resonant doublet, as well as a distinct variation with rotational phase. We examine the effect of non-radial, magnetically-channeled wind outflow on P-Cygni line formation, using a Sobolev Exact Integration (SEI) approach for direct comparison with HST UV spectra of NGC 1624-2. We demonstrate that the addition of a magnetic field desaturates the absorption trough of the P-Cygni profiles, but further efforts are needed to fully account for the observed line profile variation. Our study thus provides a first step toward a broader understanding of how strong magnetic fields affect mass loss diagnostics from UV lines.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiang, Chia-Ying; Cackett, Edward M.; Miller, Jon M.

Broad Fe K emission lines have been widely observed in the X-ray spectra of black hole systems as well as in neutron star systems. The intrinsically narrow Fe K fluorescent line is generally believed to be part of the reflection spectrum originating in an illuminated accretion disk which is broadened by strong relativistic effects. However, the nature of the lines in neutron star low-mass X-ray binaries (LMXBs) has been a matter of debate. We therefore obtained the longest, high-resolution X-ray spectrum of a neutron star LMXB to date with a 300 ks Chandra High Energy Transmission Grating Spectrometer (HETGS) observationmore » of Serpens X-1. The observation was taken under the “continuous clocking” mode, and thus was free of photon pile-up effects. We carry out a systematic analysis and find that the blurred reflection model fits the Fe line of Serpens X-1 significantly better than a broad Gaussian component does, implying that the relativistic reflection scenario is much preferred. Chandra HETGS also provides a highest spectral resolution view of the Fe K region and we find no strong evidence for additional narrow lines.« less

Searching for flavor labels in food products: the influence of color-flavor congruence and association strength.

PubMed

Velasco, Carlos; Wan, Xiaoang; Knoeferle, Klemens; Zhou, Xi; Salgado-Montejo, Alejandro; Spence, Charles

2015-01-01

Prior research provides robust support for the existence of a number of associations between colors and flavors. In the present study, we examined whether congruent (vs. incongruent) combinations of product packaging colors and flavor labels would facilitate visual search for products labeled with specific flavors. The two experiments reported here document a Stroop-like effect between flavor words and packaging colors. The participants were able to search for packaging flavor labels more rapidly when the color of the packaging was congruent with the flavor label (e.g., red/tomato) than when it was incongruent (e.g., yellow/tomato). In addition, when the packaging color was incongruent, those flavor labels that were more strongly associated with a specific color yielded slower reaction times and more errors (Stroop interference) than those that were less strongly tied to a specific color. Importantly, search efficiency was affected both by color/flavor congruence and association strength. Taken together, these results therefore highlight the role of color congruence and color-word association strength when it comes to searching for specific flavor labels.

Synthesis and mechanistic studies of curcumin analog-based oximes as potential anticancer agents.

PubMed

Qin, Hua-Li; Leng, Jing; Youssif, Bahaa G M; Amjad, Muhammad Wahab; Raja, Maria Abdul Ghafoor; Hussain, Muhammad Ajaz; Hussain, Zahid; Kazmi, Syeda Naveed; Bukhari, Syed Nasir Abbas

2017-09-01

The incidence of cancer can be decreased by chemoprevention using either natural or synthetic agents. Apart from synthetic compounds, numerous natural products have exhibited promising potential to inhibit carcinogenesis in vivo. In this study, α, β-unsaturated carbonyl-based anticancer compounds were used as starting materials to synthesize new oxime analogs. The findings from the antiproliferative assay using seven different human cancer cell lines provided a clear picture of structure-activity relationship. The oxime analogs namely 7a and 8a showed strong antiproliferative activity against the cell lines. The mechanistic effects of compounds on EGFR-TK kinases and tubulin polymerization and BRAF V 600E were investigated. In addition, the efficacy of compounds in reversing the efflux-mediated resistance developed by cancer cells was also studied. The compounds 5a and 6a displayed potent activity on various targets such as BRAF V 600E and EGFR-TK kinases and also exhibited strong antiproliferative activity against different cell lines hence showing potential of multifunctional anticancer agents. © 2017 John Wiley & Sons A/S.

Adaptive divergence despite strong genetic drift: genomic analysis of the evolutionary mechanisms causing genetic differentiation in the island fox (Urocyon littoralis)

PubMed Central

FUNK, W. CHRIS; LOVICH, ROBERT E.; HOHENLOHE, PAUL A.; HOFMAN, COURTNEY A.; MORRISON, SCOTT A.; SILLETT, T. SCOTT; GHALAMBOR, CAMERON K.; MALDONADO, JESUS E.; RICK, TORBEN C.; DAY, MITCH D.; POLATO, NICHOLAS R.; FITZPATRICK, SARAH W.; COONAN, TIMOTHY J.; CROOKS, KEVIN R.; DILLON, ADAM; GARCELON, DAVID K.; KING, JULIE L.; BOSER, CHRISTINA L.; GOULD, NICHOLAS; ANDELT, WILLIAM F.

2016-01-01

The evolutionary mechanisms generating the tremendous biodiversity of islands have long fascinated evolutionary biologists. Genetic drift and divergent selection are predicted to be strong on islands and both could drive population divergence and speciation. Alternatively, strong genetic drift may preclude adaptation. We conducted a genomic analysis to test the roles of genetic drift and divergent selection in causing genetic differentiation among populations of the island fox (Urocyon littoralis). This species consists of 6 subspecies, each of which occupies a different California Channel Island. Analysis of 5293 SNP loci generated using Restriction-site Associated DNA (RAD) sequencing found support for genetic drift as the dominant evolutionary mechanism driving population divergence among island fox populations. In particular, populations had exceptionally low genetic variation, small Ne (range = 2.1–89.7; median = 19.4), and significant genetic signatures of bottlenecks. Moreover, islands with the lowest genetic variation (and, by inference, the strongest historical genetic drift) were most genetically differentiated from mainland gray foxes, and vice versa, indicating genetic drift drives genome-wide divergence. Nonetheless, outlier tests identified 3.6–6.6% of loci as high FST outliers, suggesting that despite strong genetic drift, divergent selection contributes to population divergence. Patterns of similarity among populations based on high FST outliers mirrored patterns based on morphology, providing additional evidence that outliers reflect adaptive divergence. Extremely low genetic variation and small Ne in some island fox populations, particularly on San Nicolas Island, suggest that they may be vulnerable to fixation of deleterious alleles, decreased fitness, and reduced adaptive potential. PMID:26992010

Spectral editing of weakly coupled spins using variable flip angles in PRESS constant echo time difference spectroscopy: Application to GABA

NASA Astrophysics Data System (ADS)

Snyder, Jeff; Hanstock, Chris C.; Wilman, Alan H.

2009-10-01

A general in vivo magnetic resonance spectroscopy editing technique is presented to detect weakly coupled spin systems through subtraction, while preserving singlets through addition, and is applied to the specific brain metabolite γ-aminobutyric acid (GABA) at 4.7 T. The new method uses double spin echo localization (PRESS) and is based on a constant echo time difference spectroscopy approach employing subtraction of two asymmetric echo timings, which is normally only applicable to strongly coupled spin systems. By utilizing flip angle reduction of one of the two refocusing pulses in the PRESS sequence, we demonstrate that this difference method may be extended to weakly coupled systems, thereby providing a very simple yet effective editing process. The difference method is first illustrated analytically using a simple two spin weakly coupled spin system. The technique was then demonstrated for the 3.01 ppm resonance of GABA, which is obscured by the strong singlet peak of creatine in vivo. Full numerical simulations, as well as phantom and in vivo experiments were performed. The difference method used two asymmetric PRESS timings with a constant total echo time of 131 ms and a reduced 120° final pulse, providing 25% GABA yield upon subtraction compared to two short echo standard PRESS experiments. Phantom and in vivo results from human brain demonstrate efficacy of this method in agreement with numerical simulations.

Duck hepatitis A virus structural proteins expressed in insect cells self-assemble into virus-like particles with strong immunogenicity in ducklings.

PubMed

Wang, Anping; Gu, Lingling; Wu, Shuang; Zhu, Shanyuan

2018-02-01

Duck hepatitis A virus (DHAV), a non-enveloped ssRNA virus, can cause a highly contagious disease in young ducklings. The three capsid proteins of VP0, VP1 and VP3 are translated within a single large open reading frame (ORF) and hydrolyzed by protease 3CD. However, little is known on whether the recombinant viral structural proteins (VPs) expressed in insect cells could spontaneously assemble into virus-like particles (VLPs) and whether these VLPs could induce protective immunity in young ducklings. To address these issues, the structural polyprotein precursor gene P1 and the protease gene 3CD were amplified by PCR, and the recombinant proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures and immunogenicity. The recombinant proteins expressed in Sf9 cells were detected by indirect immunofluorescence assay and Western blot analysis. Electron microscopy showed that the recombinant proteins spontaneously assembled into VLPs in insect cells. Western blot analysis of the purified VLPs revealed that the VLPs were composed with the three structural proteins. In addition, vaccination with the VLPs induced high humoral immune response and provided strong protection. Therefore, our findings may provide a framework for development of new vaccines for the prevention of duck viral hepatitis. Copyright © 2018 Elsevier B.V. All rights reserved.

The puzzling first-order phase transition in water–glycerol mixtures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Popov, Ivan; Greenbaum; Sokolov, Alexei P.

2015-06-05

Over the last decade, discussions on a possible liquid-liquid transition (LLT) have strongly intensified. The LLT proposed by several authors focused mostly on explaining the anomalous properties of water in a deeply supercooled state. However, there have been no direct experimental observations yet of LLT in bulk water in the so-called 'no man's land', where water exists only in the crystalline states. Recently, a novel experimental strategy to detect LLT in water has been employed using water-glycerol (W-G) mixtures, because glycerol can generate a strong hindrance for water crystallization. As a result, the observed first-order phase transition at a concentrationmore » of glycerol around c(g) approximate to 20 mol% was ascribed to the LLT. Here we show unambiguously that the first order phase transition in W-G mixtures is caused by the ice formation. We provide additional dielectric measurements, applying specific annealing temperature protocols in order to reinforce this conclusion. We also provide an explanation, why such a phase transition occurs only in the narrow glycerol concentration range. These results clearly demonstrate the danger of analysis of phase-separating liquids to gain better insights into water dynamics. These liquids have complex phase behavior that is affected by temperature, phase stability and segregation, viscosity and nucleation, and finally by crystallization, that might lead to significant misinterpretations.« less

Semiempirical modeling of Ag nanoclusters: New parameters for optical property studies enable determination of double excitation contributions to plasmonic excitation

DOE PAGES

Gieseking, Rebecca L.; Ratner, Mark A.; Schatz, George C.

2016-06-03

Quantum mechanical studies of Ag nanoclusters have shown that plasmonic behavior can be modeled in terms of excited states where collectivity among single excitations leads to strong absorption. However, new computational approaches are needed to provide understanding of plasmonic excitations beyond the single-excitation level. We show that semiempirical INDO/CI approaches with appropriately selected parameters reproduce the TD-DFT optical spectra of various closed-shell Ag clusters. The plasmon-like states with strong optical absorption comprise linear combinations of many singly excited configurations that contribute additively to the transition dipole moment, whereas all other excited states show significant cancellation among the contributions to themore » transition dipole moment. The computational efficiency of this approach allows us to investigate the role of double excitations at the INDO/SDCI level. The Ag cluster ground states are stabilized by slight mixing with doubly excited configurations, but the plasmonic states generally retain largely singly excited character. The consideration of double excitations in all cases improves the agreement of the INDO/CI absorption spectra with TD-DFT, suggesting that the SDCI calculation effectively captures some of the ground-state correlation implicit in DFT. Furthermore, these results provide the first evidence to support the commonly used assumption that single excitations are in many cases sufficient to describe the optical spectra of plasmonic excitations quantum mechanically.« less

Phase Partitioning from Theanol Blend Gasolines

EPA Science Inventory

In recent years, the use of ethanol and other alcohols as motor fuel additives has increased. Additionally, ethanol production has expanded due to the potential use of ethanol as a primary fuel source. Historical patterns of gasoline composition show strong dependency on regulato...

A compact clinical instrument for quantifying suppression.

PubMed

Black, Joanne M; Thompson, Benjamin; Maehara, Goro; Hess, Robert F

2011-02-01

We describe a compact and convenient clinical apparatus for the measurement of suppression based on a previously reported laboratory-based approach. In addition, we report and validate a novel, rapid psychophysical method for measuring suppression using this apparatus, which makes the technique more applicable to clinical practice. By using a Z800 dual pro head-mounted display driven by a MAC laptop, we provide dichoptic stimulation. Global motion stimuli composed of arrays of moving dots are presented to each eye. One set of dots move in a coherent direction (termed signal) whereas another set of dots move in a random direction (termed noise). To quantify performance, we measure the signal/noise ratio corresponding to a direction-discrimination threshold. Suppression is quantified by assessing the extent to which it matters which eye sees the signal and which eye sees the noise. A space-saving, head-mounted display using current video technology offers an ideal solution for clinical practice. In addition, our optimized psychophysical method provided results that were in agreement with those produced using the original technique. We made measures of suppression on a group of nine adult amblyopic participants using this apparatus with both the original and new psychophysical paradigms. All participants had measurable suppression ranging from mild to severe. The two different psychophysical methods gave a strong correlation for the strength of suppression (rho = -0.83, p = 0.006). Combining the new apparatus and new psychophysical method creates a convenient and rapid technique for parametric measurement of interocular suppression. In addition, this apparatus constitutes the ideal platform for suppressors to combine information between their eyes in a similar way to binocularly normal people. This provides a convenient way for clinicians to implement the newly proposed binocular treatment of amblyopia that is based on antisuppression training.

Application of the Haines Index in the fire warning system

NASA Astrophysics Data System (ADS)

Kalin, Lovro; Marija, Mokoric; Tomislav, Kozaric

2016-04-01

Croatia, as all Mediterranean countries, is strongly affected by large wildfires, particularly in the coastal region. In the last two decades the number and intensity of fires has been significantly increased, which is unanimously associated with climate change, e.g. global warming. More extreme fires are observed, and the fire-fighting season has been expanded to June and September. The meteorological support for fire protection and planning is therefore even more important. At the Meteorological and Hydrological Service of Croatia a comprehensive monitoring and warning system has been established. It includes standard components, such as short term forecast of Fire Weather Index (FWI), but long range forecast as well. However, due to more frequent hot and dry seasons, FWI index often does not provide additional information of extremely high fire danger, since it regularly takes the highest values for long periods. Therefore the additional tools have been investigated. One of widely used meteorological products is the Haines index (HI). It provides information of potential fire growth, taking into account only the vertical instability of the atmosphere, and not the state of the fuel. Several analyses and studies carried out at the Service confirmed the correlation of high HI values with large and extreme fires. The Haines index forecast has been used at the Service for several years, employing European Centre for Medium Range Weather Forecast (ECMWF) global prediction model, as well as the limited-area Aladin model. The verification results show that these forecast are reliable, when compared to radiosonde measurements. All these results provided the introduction of the additional fire warnings, that are issued by the Service's Forecast Department.

The first does the work, but the third time's the charm: the effects of massed repetition on episodic encoding of multimodal face-name associations.

PubMed

Mangels, Jennifer A; Manzi, Alberto; Summerfield, Christopher

2010-03-01

In social interactions, it is often necessary to rapidly encode the association between visually presented faces and auditorily presented names. The present study used event-related potentials to examine the neural correlates of associative encoding for multimodal face-name pairs. We assessed study-phase processes leading to high-confidence recognition of correct pairs (and consistent rejection of recombined foils) as compared to lower-confidence recognition of correct pairs (with inconsistent rejection of recombined foils) and recognition failures (misses). Both high- and low-confidence retrieval of face-name pairs were associated with study-phase activity suggestive of item-specific processing of the face (posterior inferior temporal negativity) and name (fronto-central negativity). However, only those pairs later retrieved with high confidence recruited a sustained centro-parietal positivity that an ancillary localizer task suggested may index an association-unique process. Additionally, we examined how these processes were influenced by massed repetition, a mnemonic strategy commonly employed in everyday situations to improve face-name memory. Differences in subsequent memory effects across repetitions suggested that associative encoding was strongest at the initial presentation, and thus, that the initial presentation has the greatest impact on memory formation. Yet, exploratory analyses suggested that the third presentation may have benefited later memory by providing an opportunity for extended processing of the name. Thus, although encoding of the initial presentation was critical for establishing a strong association, the extent to which processing was sustained across subsequent immediate (massed) presentations may provide additional encoding support that serves to differentiate face-name pairs from similar (recombined) pairs by providing additional encoding opportunities for the less dominant stimulus dimension (i.e., name).

Measuring Critical Care Providers' Attitudes About Controlled Donation After Circulatory Death.

PubMed

Rodrigue, James R; Luskin, Richard; Nelson, Helen; Glazier, Alexandra; Henderson, Galen V; Delmonico, Francis L

2018-06-01

Unfavorable attitudes and insufficient knowledge about donation after cardiac death among critical care providers can have important consequences for the appropriate identification of potential donors, consistent implementation of donation after cardiac death policies, and relative strength of support for this type of donation. The lack of reliable and valid assessment measures has hampered research to capture providers' attitudes. Design and Research Aims: Using stakeholder engagement and an iterative process, we developed a questionnaire to measure attitudes of donation after cardiac death in critical care providers (n = 112) and examined its psychometric properties. Exploratory factor analysis, internal consistency, and validity analyses were conducted to examine the measure. A 34-item questionnaire consisting of 4 factors (Personal Comfort, Process Satisfaction, Family Comfort, and System Trust) provided the most parsimonious fit. Internal consistency was acceptable for each of the subscales and the total questionnaire (Cronbach α > .70). A strong association between more favorable attitudes overall and knowledge ( r = .43, P < .001) provides evidence of convergent validity. Multivariable regression analyses showed that white race ( P = .002) and more experience with donation after cardiac death ( P < .001) were significant predictors of more favorable attitudes. Study findings support the utility, reliability, and validity of a questionnaire for measuring attitudes in critical care providers and for isolating targets for additional education on donation after cardiac death.

Links between Soil Fungal Diversity and Plant and Soil Properties on the Loess Plateau

PubMed Central

Yang, Yang; Dou, Yanxing; Huang, Yimei; An, Shaoshan

2017-01-01

Previous studies have revealed inconsistent correlations between fungal diversity and plant/soil properties from local to global scales. Here, we investigated the internal relationships between soil fungal diversity and plant/soil properties on the Loess Plateau following vegetation restoration, using Illumina sequencing of the internal transcribed spacer 2 (ITS2) region for fungal identification. We found significant effects of land use types (Af, Artificial forest; Ns, Natural shrub; Ag, Artificial grassland; Ng, Natural grassland; Sc, slope cropland) on soil fungal communities composition, and the dominant phyla were Ascomycota, Basidiomycota, and Zygomycota, which transitioned from Basidiomycota-dominant to Ascomycota-dominant community due to vegetation restoration. The Chao1 richness, Shannon’s diversity and ACE indices were significantly influenced by land use types with the order of Ns > Af > Ng > Ag > Sc, and the total number of OTUs varied widely. In contrast, Good’s coverage and Simpson’s diversity indicated no significant difference among land use types (p > 0.05). Correlation analysis showed that plant and soil properties were closely related to fungal diversity regardless of land use types. In addition, soil organic carbon (SOC) and Hplant (plant richness, Shannon-Wiener index) were strong driving factors that explained fungal diversity. As revealed by the structural equation model (SEM) and generalized additive models (GAMs), fungal diversity was directly and indirectly affected by soil and plant properties, respectively, providing evidence for strong links between soil fungal diversity and plant and soil properties on the Loess Plateau. PMID:29163460

Links between Soil Fungal Diversity and Plant and Soil Properties on the Loess Plateau.

PubMed

Yang, Yang; Dou, Yanxing; Huang, Yimei; An, Shaoshan

2017-01-01

Previous studies have revealed inconsistent correlations between fungal diversity and plant/soil properties from local to global scales. Here, we investigated the internal relationships between soil fungal diversity and plant/soil properties on the Loess Plateau following vegetation restoration, using Illumina sequencing of the internal transcribed spacer 2 (ITS2) region for fungal identification. We found significant effects of land use types (Af, Artificial forest; Ns, Natural shrub; Ag, Artificial grassland; Ng, Natural grassland; Sc, slope cropland) on soil fungal communities composition, and the dominant phyla were Ascomycota, Basidiomycota , and Zygomycota , which transitioned from Basidiomycota -dominant to Ascomycota -dominant community due to vegetation restoration. The Chao1 richness, Shannon's diversity and ACE indices were significantly influenced by land use types with the order of Ns > Af > Ng > Ag > Sc, and the total number of OTUs varied widely. In contrast, Good's coverage and Simpson's diversity indicated no significant difference among land use types ( p > 0.05). Correlation analysis showed that plant and soil properties were closely related to fungal diversity regardless of land use types. In addition, soil organic carbon (SOC) and H plant (plant richness, Shannon-Wiener index) were strong driving factors that explained fungal diversity. As revealed by the structural equation model (SEM) and generalized additive models (GAMs), fungal diversity was directly and indirectly affected by soil and plant properties, respectively, providing evidence for strong links between soil fungal diversity and plant and soil properties on the Loess Plateau.

Three-photon imaging of ovarian cancer

NASA Astrophysics Data System (ADS)

Barton, Jennifer K.; Amirsolaimani, Babak; Rice, Photini; Hatch, Kenneth; Kieu, Khanh

2016-02-01

Optical imaging methods have the potential to detect ovarian cancer at an early, curable stage. Optical imaging has the disadvantage that high resolution techniques require access to the tissue of interest, but miniature endoscopes that traverse the natural orifice of the reproductive tract, or access the ovaries and fallopian tubes through a small incision in the vagina wall, can provide a minimally-invasive solution. We have imaged both rodent and human ovaries and fallopian tubes with a variety of endoscope-compatible modalities. The recent development of fiber-coupled femtosecond lasers will enable endoscopic multiphoton microscopy (MPM). We demonstrated two- and three-photon excited fluorescence (2PEF, 3PEF), and second- and third-harmonic generation microscopy (SHG, THG) in human ovarian and fallopian tube tissue. A study was undertaken to understand the mechanisms of contrast in these images. Six patients (normal, cystadenoma, and ovarian adenocarcinoma) provided ovarian and fallopian tube biopsies. The tissue was imaged with three-dimensional optical coherence tomography, multiphoton microscopy, and frozen for histological sectioning. Tissue sections were stained with hematoxylin and eosin, Masson's trichrome, and Sudan black. Approximately 1 μm resolution images were obtained with an excitation source at 1550 nm. 2PEF signal was absent. SHG signal was mainly from collagen. 3PEF and THG signal came from a variety of sources, including a strong signal from fatty connective tissue and red blood cells. Adenocarcinoma was characterized by loss of SHG signal, whereas cystic abnormalities showed strong SHG. There was limited overlap of two- and three- photon signals, suggesting that three-photon imaging can provide additional information for early diagnosis of ovarian cancer.

The ambiguity of drought events, a bottleneck for Amazon forest drought response modelling

NASA Astrophysics Data System (ADS)

De Deurwaerder, Hannes; Verbeeck, Hans; Baker, Timothy; Christoffersen, Bradley; Ciais, Philippe; Galbraith, David; Guimberteau, Matthieu; Kruijt, Bart; Langerwisch, Fanny; Meir, Patrick; Rammig, Anja; Thonicke, Kirsten; Von Randow, Celso; Zhang, Ke

2016-04-01

Considering the important role of the Amazon forest in the global water and carbon cycle, the prognosis of altered hydrological patterns resulting from climate change provides strong incentive for apprehending the direct implications of drought on the vegetation of this ecosystem. Dynamic global vegetation models have the potential of providing a useful tool to study drought impacts on various spatial and temporal scales. This however assumes the models being able to properly represent drought impact mechanisms. But how well do the models succeed in meeting this assumption? Within this study meteorological driver data and model output data of 4 different DGVMs, i.e. ORCHIDEE, JULES, INLAND and LPGmL, are studied. Using the palmer drought severity index (PDSI) and the mean cumulative water deficit (MWD), temporal and spatial representation of drought events are studied in the driver data and are referenced to historical extreme drought events in the Amazon. Subsequently, within the resulting temporal and spatial frame, we studied the drought impact on the above ground biomass (AGB) and gross primary production (GPP) fluxes. Flux tower data, field inventory data and the JUNG data-driven GPP product for the Amazon region are used for validation. Our findings not only suggest that the current state of the studied DGVMs is inadequate in representing Amazon droughts in general, but also highlights strong inter-model differences in drought responses. Using scatterplot-studies and input-output correlations, we provide insight in the origin of these encountered inter-model differences. In addition, we present directives of model development and improvement in scope of Amazon forest drought response modelling.

Evidence that Magnetic Navigation and Geomagnetic Imprinting Shape Spatial Genetic Variation in Sea Turtles.

PubMed

Brothers, J Roger; Lohmann, Kenneth J

2018-04-23

The canonical drivers of population genetic structure, or spatial genetic variation, are isolation by distance and isolation by environment. Isolation by distance predicts that neighboring populations will be genetically similar and geographically distant populations will be genetically distinct [1]. Numerous examples also exist of isolation by environment, a phenomenon in which populations that inhabit similar environments (e.g., same elevation, temperature, or vegetation) are genetically similar even if they are distant, whereas populations that inhabit different environments are genetically distinct even when geographically close [2-4]. These dual models provide a widely accepted conceptual framework for understanding population structure [5-8]. Here, we present evidence for an additional, novel process that we call isolation by navigation, in which the navigational mechanism used by a long-distance migrant influences population structure independently of isolation by either distance or environment. Specifically, we investigated the population structure of loggerhead sea turtles (Caretta caretta) [9], which return to nest on their natal beaches by seeking out unique magnetic signatures along the coast-a behavior known as geomagnetic imprinting [10-12]. Results reveal that spatial variation in Earth's magnetic field strongly predicts genetic differentiation between nesting beaches, even when environmental similarities and geographic proximity are taken into account. The findings provide genetic corroboration of geomagnetic imprinting [10, 13]. Moreover, they provide strong evidence that geomagnetic imprinting and magnetic navigation help shape the population structure of sea turtles and perhaps numerous other long-distance migrants that return to their natal areas to reproduce [13-17]. Copyright © 2018 Elsevier Ltd. All rights reserved.

Social determinants and polio 'endgame': a qualitative study in high risk districts of India.

PubMed

Dasgupta, Rajib; Chaturvedi, Sanjay; Adhish, S Vivek; Ganguly, Kalyan K; Rai, Sanjay; Sushant, Leena; Arora, N K

2008-05-01

To understand the perceptions and likely determinants that facilitate or act as barriers in implementing additional strategies for polio eradication: (a) accelerated delivery of mOPV1 (monovalent polio vaccine type 1); (b) use of IPV (inactivated polio vaccine); and (c) provision of incentives. QUALITATIVE. Rapid appraisal procedures (RAP) were adopted to derive the reality by synthesizing multiple sources of information; search for opinions, motivations, behaviors and attitudes of key stakeholders within their organizational and socio-cultural matrix. Two districts of Uttar Pradesh - Moradabad and J P Nagar. Total 244 interactions were conducted; 33 interviews and 4 focussed group discussions (FGD) conducted with providers; 33 mothers (<5 years) and 10 leaders were interviewed; 8 FGD were conducted with mothers of under-fives. Informal interactions (156) were also conducted with village pradhans, religious leaders, parents, businessmen, journalists (Hindi and Urdu media), mobilizers, vaccinators and supervisors. Providers expressed reservation regarding accelerated rounds of OPV; scientific rationale of accelerated rounds is not clear to parents and leaders. Although technical advantages of introducing IPV exist, issues of logistical difficulties and injection safety emerged strongly. Providers and communities indicated a clear 'no' to the cash incentives but argued for developmental issues. Resistance to the program has declined over time but still the program is perceived as the "government's need, not ours". The polio eradication program is critically poised, an opportunity to intensify efforts for reducing inequities in health services and improve access of all children to the PHC services. Ongoing dialogue with local communities and strong political commitment would be essential to translate the technological innovations into a sustainable program.

Investigation of the seasonal variations of aerosol physicochemical properties and their impact on cloud condensation nuclei number concentration

NASA Astrophysics Data System (ADS)

Logan, Timothy S.

Aerosols are among the most complex yet widely studied components of the atmosphere not only due to the seasonal variability of their physical and chemical properties but also their effects on climate change. The three main aerosol types that are known to affect the physics and chemistry of the atmosphere are: mineral dust, anthropogenic pollution, and biomass burning aerosols. In order to understand how these aerosols affect the atmosphere, this dissertation addresses the following three scientific questions through a combination of surface and satellite observations: SQ1: What are the seasonal and regional variations of aerosol physico-chemical properties at four selected Asian sites? SQ2: How do these aerosol properties change during transpacific and intra-continental long range transport? SQ3: What are the impacts of aerosol properties on marine boundary layer cloud condensation nuclei number concentration? This dissertation uses an innovative approach to classify aerosol properties by region and season to address SQ1. This is useful because this method provides an additional dimension when investigating the physico-chemical properties of aerosols by linking a regional and seasonal dependence to both the aerosol direct and indirect effects. This method involves isolating the aerosol physico-chemical properties into four separate regions using AERONET retrieved Angstrom exponent (AEAOD) and single scattering co-albedo (o oabs) to denote aerosol size and absorptive properties. The aerosols events are then clustered by season. The method is first applied to four AERONET sites representing single mode aerosol dominant regions: weakly absorbing pollution (NASA Goddard), strongly absorbing pollution (Mexico City), mineral dust (Solar Village), and biomass burning smoke (Alta Floresta). The method is then applied to four Asian sites that represent complicated aerosol components. There are strong regional and seasonal influences of the four aerosol types over the selected four Asian sites. A strongly absorbing mineral dust influence is seen at the Xianghe, Taihu, and SACOL sites during the spring months (MAM) as given by coarse mode dominance. There is a shift towards weakly absorbing pollution (sulfate) and biomass (OC) aerosol dominance in the summer (JJA) and autumn (SON) months as given by a strong fine mode influence. A winter season (DJF) shift toward strongly fine mode, absorbing particles (BC and OC) is observed at Xianghe and Taihu. At Mukdahan, a strong fine mode influence is evident year round with weakly and strongly absorbing biomass particles dominant in the autumn and winter months, respectively, while particles exhibit variable absorption during the spring season. To address SQ2, four cases are selected in Asia to investigate how the optical properties of Asian aerosol plumes change during transport across the remote Pacific Ocean. In addition, six strong smoke events are selected to investigate how the physical and chemical properties of biomass smoke aerosols change during transport in North America. From four selected Asian cases, it was shown by DC-8 aircraft in situ measurements that the Asian plumes contained varying amounts of mineral dust and pollution aerosols during transport. In addition, backward trajectory analysis identified two main dust source regions (Gobi and Taklamakan deserts) and urban/industrial pollution regions in central and eastern China. During the anomalously active wildfire season of 2012 in North America, strong smoke events were observed over the Northern Great Plains region by the Grand Forks, North Dakota, AERONET site and selected as cases. The spectral dependences of absorption aerosol optical depth (AAOD) and o oabs illustrated the varying absorption of the smoke plumes due to carbonaceous particle influences. The AAOD parameter was found to be primarily influenced by aerosol particle size while ooabs was more sensitive to the carbonaceous content. The aerosols likely contain strongly absorbing carbonaceous particles generated from the flaming combustion mode. The cases represented complex mixtures of the flaming and smoldering combustion phases. Lastly, SQ3 is addressed by using a multi-platform dataset from the Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) Graciosa, Azores, 2009-2010 field campaign. The seasonal aerosol particle volume and number size distributions, AOD, and AEAOD during the CAP-MBL campaign have shown that a low overall mean AOD440 of 0.12 denoted a clean environment over this region that typically contains MBL sea salt. In terms of aerosol volume, a bimodal signal was prominent where the coarse mode influence (r ≥ 1 μm) dominated that of the fine mode (r < 1 μm) throughout the year. However, there are considerable continental fine mode aerosols advected to the Azores region during summer months, including Saharan mineral dust, volcanic ash, biomass smoke, and pollution from North American as identified by HYSPLIT backward trajectories. These aerosol types have been shown to have impacts on MBL cloud condensation nuclei (CCN) that are likely different from coarse mode marine aerosols (e.g., sea salt) (Remillard et al. 2014; Wood et al. 2014). The alternating presence of dominant clean air masses with periodic episodes of polluted air masses will provide a substantial variety in aerosol properties during the summer. This will provide a great opportunity to investigate the interactions between aerosol and cloud properties in terms of the aerosol indirect effect (AIE).

Insights into the Anaerobic Biodegradation Pathway of n-Alkanes in Oil Reservoirs by Detection of Signature Metabolites

PubMed Central

Bian, Xin-Yu; Maurice Mbadinga, Serge; Liu, Yi-Fan; Yang, Shi-Zhong; Liu, Jin-Feng; Ye, Ru-Qiang; Gu, Ji-Dong; Mu, Bo-Zhong

2015-01-01

Anaerobic degradation of alkanes in hydrocarbon-rich environments has been documented and different degradation strategies proposed, of which the most encountered one is fumarate addition mechanism, generating alkylsuccinates as specific biomarkers. However, little is known about the mechanisms of anaerobic degradation of alkanes in oil reservoirs, due to low concentrations of signature metabolites and lack of mass spectral characteristics to allow identification. In this work, we used a multidisciplinary approach combining metabolite profiling and selective gene assays to establish the biodegradation mechanism of alkanes in oil reservoirs. A total of twelve production fluids from three different oil reservoirs were collected and treated with alkali; organic acids were extracted, derivatized with ethanol to form ethyl esters and determined using GC-MS analysis. Collectively, signature metabolite alkylsuccinates of parent compounds from C1 to C8 together with their (putative) downstream metabolites were detected from these samples. Additionally, metabolites indicative of the anaerobic degradation of mono- and poly-aromatic hydrocarbons (2-benzylsuccinate, naphthoate, 5,6,7,8-tetrahydro-naphthoate) were also observed. The detection of alkylsuccinates and genes encoding for alkylsuccinate synthase shows that anaerobic degradation of alkanes via fumarate addition occurs in oil reservoirs. This work provides strong evidence on the in situ anaerobic biodegradation mechanisms of hydrocarbons by fumarate addition. PMID:25966798

Differential responses to guano fertilization among tropical tree species with varying functional traits.

PubMed

Young, Hillary S; McCauley, Douglas J; Dirzo, Rodolfo

2011-02-01

Seabirds often cause significant changes to soil properties, and seabird-dominated systems often host unique plant communities. This study experimentally (1) examined species-specific responses to seabird guano gradients, (2) considered the role that differential functional traits among species play in altering plant response to guano, and (3) investigated the implications of seabird guano on range-expanding species. Using a greenhouse fertilization experiment, we examined how guano fertilization affects the growth and functional traits of four tree species dominant in the Pacific Islands: Cocos nucifera, Pisonia grandis, Scaevola sericea, and Tournefortia argentea. In these systems, seabirds are frequently found in association with three of these four species; the remaining species, C. nucifera, is a recently proliferating species commonly found in the region but rarely associated with seabirds. We determined that responses to guano addition differed significantly between species in ways that were consistent with predictions based on differing functional traits among species. Notably, we demonstrated that C. nucifera showed no growth responses to guano additions, whereas all seabird-associated plants showed strong responses. These results provide experimental evidence of differential species response to guano additions, suggesting that differences in species functional traits may contribute to changes in plant communities in seabird-dominated areas, with seabird-associated species garnering performance advantages in these high-nutrient environments. Among these species, results also suggest that C. nucifera may have a competitive advantage in low-nutrient environments, providing an unusual example of how a range-expanding plant species can profit from low-nutrient environments.

Strong motion instrumentation of an RC building structure

USGS Publications Warehouse

Li, H.-J.; Celebi, M.

2001-01-01

The strong-motion instrumentation scheme of a reinforced concrete building observed by California Strong-Motion Instrumentation Program (CSMIP) is introduced in this paper. The instrumented building is also described and the recorded responses during 1994 Northridge earthquake are provided.

Measurement and optimization of the light collection uniformity in strongly tapered PWO crystals of the PANDA detector

NASA Astrophysics Data System (ADS)

Diehl, Stefan; Bremer, Daniel; Brinkmann, Kai-Thomas; Dormenev, Valery; Eissner, Tobias; Novotny, Rainer W.; Rosenbaum, Christoph; Zaunick, Hans-Georg; PANDA Collaboration

2017-06-01

The uniformity of the light collection is a crucial parameter for detectors based on inorganic scintillation crystals to guarantee a response proportional to the deposited energy. Especially in case of tapered crystals, like they are widely used to realize a 4π geometry of electromagnetic calorimeters (EMC) in high energy physics experiments, a strong non-uniformity is introduced by an additional focusing of the scintillation light due to the tapered geometry. The paper will discuss the determination and the reduction of the non-uniformity in strongly tapered lead tungstate crystals as used for the construction of the electromagnetic calorimeter of the PANDA detector at the future Facility for Antiproton and Ion Research (FAIR). Among different concepts for an uniformization a single de-polished lateral side face provided the optimum result with a remaining non-uniformity below 5% in good agreement with similar studies for the CMS ECAL at LHC. The impact on the achievable energy resolution in the energy regime of photons below 800 MeV is discussed in detail in comparison to GEANT4 simulations. The comparison of the response of two arrays with polished and de-polished crystals, respectively, shows in the latter case a significant improvement of the constant term of the parametrization of the energy resolution down to 0.5% accompanied by only very slight increase of the statistical term.

Retinotopic patterns of functional connectivity between V1 and large-scale brain networks during resting fixation

PubMed Central

Griffis, Joseph C.; Elkhetali, Abdurahman S.; Burge, Wesley K.; Chen, Richard H.; Bowman, Anthony D.; Szaflarski, Jerzy P.; Visscher, Kristina M.

2016-01-01

Psychophysical and neurobiological evidence suggests that central and peripheral vision are specialized for different functions. This specialization of function might be expected to lead to differences in the large-scale functional interactions of early cortical areas that represent central and peripheral visual space. Here, we characterize differences in whole-brain functional connectivity among sectors in primary visual cortex (V1) corresponding to central, near-peripheral, and far-peripheral vision during resting fixation. Importantly, our analyses reveal that eccentricity sectors in V1 have different functional connectivity with non-visual areas associated with large-scale brain networks. Regions associated with the fronto-parietal control network are most strongly connected with central sectors of V1, regions associated with the cingulo-opercular control network are most strongly connected with near-peripheral sectors of V1, and regions associated with the default mode and auditory networks are most strongly connected with far-peripheral sectors of V1. Additional analyses suggest that similar patterns are present during eyes-closed rest. These results suggest that different types of visual information may be prioritized by large-scale brain networks with distinct functional profiles, and provide insights into how the small-scale functional specialization within early visual regions such as V1 relates to the large-scale organization of functionally distinct whole-brain networks. PMID:27554527

Extreme events in total ozone over the Northern mid-latitudes: an analysis based on long-term data sets from five European ground-based stations

NASA Astrophysics Data System (ADS)

Rieder, Harald E.; Jancso, Leonhardt M.; Rocco, Stefania Di; Staehelin, Johannes; Maeder, Joerg A.; Peter, Thomas; Ribatet, Mathieu; Davison, Anthony C.; de Backer, Hugo; Koehler, Ulf; Krzyścin, Janusz; Vaníček, Karel

2011-11-01

We apply methods from extreme value theory to identify extreme events in high (termed EHOs) and low (termed ELOs) total ozone and to describe the distribution tails (i.e. very high and very low values) of five long-term European ground-based total ozone time series. The influence of these extreme events on observed mean values, long-term trends and changes is analysed. The results show a decrease in EHOs and an increase in ELOs during the last decades, and establish that the observed downward trend in column ozone during the 1970-1990s is strongly dominated by changes in the frequency of extreme events. Furthermore, it is shown that clear ‘fingerprints’ of atmospheric dynamics (NAO, ENSO) and chemistry [ozone depleting substances (ODSs), polar vortex ozone loss] can be found in the frequency distribution of ozone extremes, even if no attribution is possible from standard metrics (e.g. annual mean values). The analysis complements earlier analysis for the world's longest total ozone record at Arosa, Switzerland, confirming and revealing the strong influence of atmospheric dynamics on observed ozone changes. The results provide clear evidence that in addition to ODS, volcanic eruptions and strong/moderate ENSO and NAO events had significant influence on column ozone in the European sector.

Enzyme architecture: optimization of transition state stabilization from a cation-phosphodianion pair.

PubMed

Reyes, Archie C; Koudelka, Astrid P; Amyes, Tina L; Richard, John P

2015-04-29

The side chain cation of R269 lies at the surface of l-glycerol 3-phosphate dehydrogenase (GPDH) and forms an ion pair to the phosphodianion of substrate dihydroxyacetone phosphate (DHAP), which is buried at the nonpolar protein interior. The R269A mutation of GPDH results in a 110-fold increase in K(m) (2.8 kcal/mol effect) and a 41,000-fold decrease in k(cat) (6.3 kcal/mol effect), which corresponds to a 9.1 kcal/mol destabilization of the transition state for GPDH-catalyzed reduction of DHAP by NADH. There is a 6.7 kcal/mol stabilization of the transition state for the R269A mutant GPDH-catalyzed reaction by 1.0 M guanidinium ion, and the transition state for the reaction of the substrate pieces is stabilized by an additional 2.4 kcal/mol by their covalent attachment at wildtype GPDH. These results provide strong support for the proposal that GPDH invests the 11 kcal/mol intrinsic phosphodianion binding energy of DHAP in trapping the substrate at a nonpolar active site, where strong electrostatic interactions are favored, and obtains a 9 kcal/mol return from stabilizing interactions between the side chain cation and transition state trianion. We propose a wide propagation for the catalytic motif examined in this work, which enables strong transition state stabilization from enzyme-phosphodianion pairs.

Hydrazine-enhanced NO conversion in a pulsed corona discharge plasma (PCDP) reactor: Behaviors and mechanism

NASA Astrophysics Data System (ADS)

Hong, Liu; Chen, De-Zhen; Yin, Li-Jie; Chen, Hui; Wang, Du; Hu, Yu-Yan

2016-09-01

The NO conversion efficiency in a pulsed corona discharge plasma (PCDP) reactor in the presence of a new additive, hydrazine hydrate (N2H4.H2O), was studied, and the reaction mechanism was analyzed. The NO conversion efficiency reached 62.5%, and the NO conversion Energy Yield (EY) reached 20.9 gNO/kWh, which is higher than that obtained using water or ammonia additives under the same conditions. The predominant elementary reactions and radicals, as well as the mechanism by which the additive enhanced the NO conversion process, were determined by comparing experimental data with theoretical simulation results and by performing a sensitivity analysis. After the addition of N2H4.H2O, the N2H4 reacts with radicals generated in the PCDP reactor to form a large quantity of strongly reducing species with NH2 as the predominant component, which can directly reduce NO to N2 and effectively prevent the generation of N2O. Compared with the traditional PCDP-based De-NOx process in which nitric acid is generated by oxidation with an additional neutralization step required, this new PCDP-based De-NOx process with N2H4.H2O addition is superior because NO is mostly reduced to N2. The study provides a basis for the application of N2H4.H2O as a synergist to improve NO abatement in a PCDP reactor.

First Satellite Observations of Lower Tropospheric Ammonia and Methanol

NASA Technical Reports Server (NTRS)

Beer, Reinhard; Shephard, Mark W.; Kulawik, Susan S.; Clough, Shepard A.; Eldering, Annmarie; Bowman, Kevin W.; Sander, Stanley P.; Fisher, Brendan M.; Payne, Vivienne H.; Luo, Mingzhao;

Detection of sub-threshold periodic signal by multiplicative and additive cross-correlated sine-Wiener noises in the FitzHugh-Nagumo neuron

NASA Astrophysics Data System (ADS)

Yao, Yuangen; Ma, Chengzhang; Wang, Canjun; Yi, Ming; Gui, Rong

2018-02-01

We study the effects of multiplicative and additive cross-correlated sine-Wiener (CCSW) noises on the performance of sub-threshold periodic signal detection in the FitzHugh-Nagumo (FHN) neuron by calculating Fourier coefficients Q for measuring synchronization between sub-threshold input signal and the response of system. CCSW noises-induced transitions of electrical activity in the FHN neuron model can be observed. Moreover, the performance of sub-threshold periodic signal detection is achieved at moderate noise strength, cross-correlation time and cross-correlation strength of CCSW noises, which indicate the occurrence of CCSW noises-induced stochastic resonance. Furthermore, the performance of sub-threshold signal detection is strongly sensitive to cross-correlation time of CCSW noises. Therefore, the performance can be effectively controlled by regulating cross-correlation time of CCSW noises. These results provide a possible mechanism for amplifying or detecting the sub-threshold signal in the nervous system.

Training the approximate number system improves math proficiency.

PubMed

Park, Joonkoo; Brannon, Elizabeth M

2013-10-01

Humans and nonhuman animals share an approximate number system (ANS) that permits estimation and rough calculation of quantities without symbols. Recent studies show a correlation between the acuity of the ANS and performance in symbolic math throughout development and into adulthood, which suggests that the ANS may serve as a cognitive foundation for the uniquely human capacity for symbolic math. Such a proposition leads to the untested prediction that training aimed at improving ANS performance will transfer to improvement in symbolic-math ability. In the two experiments reported here, we showed that ANS training on approximate addition and subtraction of arrays of dots selectively improved symbolic addition and subtraction. This finding strongly supports the hypothesis that complex math skills are fundamentally linked to rudimentary preverbal quantitative abilities and provides the first direct evidence that the ANS and symbolic math may be causally related. It also raises the possibility that interventions aimed at the ANS could benefit children and adults who struggle with math.

Absorption-enhanced imaging through scattering media using carbon black nano-particles: from visible to near infrared wavelengths

NASA Astrophysics Data System (ADS)

Tanzid, Mehbuba; Hogan, Nathaniel J.; Robatjazi, Hossein; Veeraraghavan, Ashok; Halas, Naomi J.

2018-05-01

Imaging through scattering media can be improved with the addition of absorbers, since multiply-scattered photons, with their longer path length, are absorbed with a higher probability than ballistic photons. The image resolution enhancement is substantially greater when imaging through isotropic scatterers than when imaging through an ensemble of strongly forward-scattering particles. However, since the angular scattering distribution is determined by the size of the scatterers with respect to the wavelength of incident light, particles that are forward scatterers at visible wavelengths can be isotropic scatterers at infrared (IR) wavelengths. Here, we show that substantial image resolution enhancement can be achieved in the near-infrared wavelength regime for particles that are forward scattering at visible wavelengths using carbon black nanoparticles as a broadband absorber. This observation provides a new strategy for image enhancement through scattering media: by selecting the appropriate wavelength range for imaging, in this case the near-IR, the addition of absorbers more effectively enhances the image resolution.

On the interplay of gas dynamics and the electromagnetic field in an atmospheric Ar/H2 microwave plasma torch

NASA Astrophysics Data System (ADS)

Synek, Petr; Obrusník, Adam; Hübner, Simon; Nijdam, Sander; Zajíčková, Lenka

2015-04-01

A complementary simulation and experimental study of an atmospheric pressure microwave torch operating in pure argon or argon/hydrogen mixtures is presented. The modelling part describes a numerical model coupling the gas dynamics and mixing to the electromagnetic field simulations. Since the numerical model is not fully self-consistent and requires the electron density as an input, quite extensive spatially resolved Stark broadening measurements were performed for various gas compositions and input powers. In addition, the experimental part includes Rayleigh scattering measurements, which are used for the validation of the model. The paper comments on the changes in the gas temperature and hydrogen dissociation with the gas composition and input power, showing in particular that the dependence on the gas composition is relatively strong and non-monotonic. In addition, the work provides interesting insight into the plasma sustainment mechanism by showing that the power absorption profile in the plasma has two distinct maxima: one at the nozzle tip and one further upstream.

First satellite observations of lower tropospheric ammonia and methanol

NASA Astrophysics Data System (ADS)

Beer, Reinhard; Shephard, Mark W.; Kulawik, Susan S.; Clough, Shepard A.; Eldering, Annmarie; Bowman, Kevin W.; Sander, Stanley P.; Fisher, Brendan M.; Payne, Vivienne H.; Luo, Mingzhao; Osterman, Gregory B.; Worden, John R.

2008-05-01

The Tropospheric Emission Spectrometer (TES) on the EOS Aura satellite makes global measurements of infrared radiances which are used to derive profiles of species such as O3, CO, H2O, HDO and CH4 as routine standard products. In addition, TES has a variety of special modes that provide denser spatial mapping over a limited geographical area. A continuous-coverage mode (called ``transect'', about 460 km long) has now been used to detect additional molecules indicative of regional air pollution. On 10 July 2007 at about 05:37 UTC (13:24 LMST) TES conducted such a transect observation over the Beijing area in northeast China. Examination of the residual spectral radiances following the retrieval of the TES standard products revealed surprisingly strong features attributable to enhanced concentrations of ammonia (NH3) and methanol (CH3OH), well above the normal background levels. This is the first time that these molecules have been detected in space-based nadir viewing measurements that penetrate into the lower atmosphere.

Compatibility of switchgrass as an energy crop in farming systems of the southeastern USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bransby, D.I.; Rodriguez-Kabana, R.; Sladden, S.E.

1993-12-31

The objective of this paper is to examine the compatibility of switchgrass as an energy crop in farming systems in the southeastern USA, relative to other regions. In particular, the issues addressed are (1) competition between switchgrass as an energy crop and existing farm enterprises, based primarily on economic returns, (2) complementarity between switchgrass and existing farm enterprises, and (3) environmental benefits. Because projected economic returns for switchgrass as an energy crop are highest in the Southeast, and returns from forestry and beef pastures (the major existing enterprises) are low, there is a very strong economic incentive in this region.more » In contrast, based on current information, economic viability of switchgrass as an energy crop in other regions appears doubtful. In addition, switchgrass in the southeastern USA would complement forage-livestock production, row crop production and wildlife and would provide several additional environmental benefits. It is concluded that the southeastern USA offers the greatest opportunity for developing switchgrass as an economically viable energy crop.« less

High performance addition-type thermoplastics (ATTs) - Evidence for the formation of a Diels-Alder adduct in the reaction of an acetylene-terminated material and a bismaleimide

NASA Technical Reports Server (NTRS)

Pater, R. H.; Soucek, M. D.; Chang, A. C.; Partos, R. D.

1991-01-01

Recently, the concept and demonstration of a new versatile synthetic reaction for making a large number of high-performance addition-type thermoplastics (ATTs) were reported. The synthesis shows promise for providing polymers having an attractive combination of easy processability, good toughness, respectable high temperature mechanical performance, and excellent thermo-oxidative stability. The new chemistry involves the reaction of an acetylene-terminated material with a bismaleimide or benzoquinone. In order to clarify the reaction mechanism, model compound studies were undertaken in solutions as well as in the solid state. The reaction products were purified by flash chromatography and characterized by conventional analytical techniques including NMR, FT-IR, UV-visible, mass spectroscopy, and high pressure liquid chromatography. The results are presented of the model compound studies which strongly support the formation of a Diels-Alder adduct in the reaction of an acetylene-terminated compound and a bismaleimide or benzoquinone.