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The application of open standards to enhance the interoperability of geoscience information

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International Journal of Digital Earth 2010年第S1期3卷 14-30页

作者： G.Percivall Open Geospatial Consortium HerndonVAUSA

We can adequately study broad global issues and policies only by taking geosciences into *** research and decision-making must share and make effective use of interdisciplinary data sources,models,and *** impedes sharing of data and computing *** from the Open Geospatial Consortium(OGC)and other organizations are the basis for successfully deploying a seamless,distributed information infrastructure for the *** specifications now adopted by the OGC consensus process are the result of OGC interoperability *** OGC standards,deployment architectures,and interoperability initiatives are described showing how the OGC standards baseline has been developed and applies to the geosciences.

关键词： geosciences interoperability open standards Open Geospatial Consortium geoinformatics geospatial data integration Digital Earth architecture spatial data infrastructure data exchange models

An adaptive Markov chain algorithm applied over map-matching of vehicle trip GPS data

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Geo-Spatial Information Science 2021年第3期24卷 484-497页

作者： Bilge Kaan Karamete Louai Adhami Eli Glaser Engineering GeospatialKinetica DB IncArlingtonVAUSA

Markov chains have frequently been applied to match the probable routes with a set of GPS trip data that a pilot vehicle is emitting over a specific graph road network. This class of mapmatching (MM) algorithms presently demonstrates and involve statistical and ad-hoc measures to drive the Markov chain transitional probabilities in picking the best route combinations constrained over the graph road network. In this study, we have devised an adaptive scheme to modify the Markov Chain (MC) kernel window as we move along the GPS samples to reduce the mistakes that can happen by the use of narrower MC widths. The measure for temporarily increasing the MC window width is chosen to be the ratio between the geodesic distance of current route to the actual geodesic distance between each pair of GPS samples. This adaptive use of MC has shown to have hardened the results significantly with tolerable computational cost increase. The details of the overall algorithm are depicted by the example routes extracted from various vehicle trips and the results are shown to validate the usefulness of the algorithm in practice.

关键词： Hidden Markov chain(HMC) map-matching(MM) graph networks

Machine learning nonequilibrium electron forces for spin dynamics of itinerant magnets

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npj Computational Materials 2023年第1期9卷 2026-2035页

作者： Puhan Zhang Gia-Wei Chern Department of Physics University of VirginiaCharlottesvilleVA 22904USA

We present a generalized potential theory for conservative as well as nonconservative forces for the Landau-Lifshitz magnetizationdynamics. Importantly, this formulation makes possible an elegant generalization of the Behler-Parrinello machine learning (ML)approach, which is a cornerstone of ML-based quantum molecular dynamics methods, to the modeling of force fields in adiabatic spindynamics of out-of-equilibrium itinerant magnetic systems. We demonstrate our approach by developing a deep-learning neuralnetwork that successfully learns the electron-mediated exchange fields in a driven s-d model computed from the nonequilibriumGreen’s function method. We show that dynamical simulations with forces predicted from the neural network accurately reproducethe voltage-driven domain-wall propagation. Our work also lays the foundation for ML modeling of spin transfer torques and opens aavenue for ML-based multi-scale modeling of nonequilibrium dynamical phenomena in itinerant magnets and spintronics.

关键词： dynamics nonequilibrium forces

Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,Virginia,USA

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Journal of Forestry Research 2020年第4期31卷 1255-1270页

作者： Lauren V.Austin Alexander Silvis W.Mark Ford Karen E.Powers Department of Fish and Wildlife Conservation Virginia TechBlacksburgVA 24061USA Resource Environmental Solutions WarrentonVA 20187USA U.S.Geological Survey Virginia Cooperative Fish and Wildlife Research UnitBlacksburgVA 24061USA Biology Department Radford UniversityRadfordVA 24141USA

Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat *** wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn *** examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),Virginia,*** was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)***,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy *** results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians.

关键词： Appalachian mountains Bats False-positive occupancy Prescribed fire Wildfire

Amino Acid Export in Plants： A Missing Link in Nitrogen Cycling

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Molecular Plant 2011年第3期4卷 453-463页

作者： Sakiko Okumoto Guillaume Pilot 549 Latham Hall Virginia Tech Blacksburg VA 24061 USA 209 Latham Hall Virginia Tech Blacksburg VA 24061 USA

The export of nutrients from source organs to parts of the body where they are required （e.g. sink organs） is a fundamental biological process. Export of amino acids, one of the most abundant nitrogen species in plant long-distance transport tissues （i.e. xylem and phloem）, is an essential process for the proper distribution of nitrogen in the plant. Phys- iological studies have detected the presence of multiple amino acid export systems in plant cell membranes. Yet, surpris- ingly little is known about the molecular identity of amino acid exporters, partially due to the technical difficulties hampering the identification of exporter proteins. In this short review, we will summarize our current knowledge about amino acid export systems in plants. Several studies have described plant amino acid transporters capable of bi-directional, facilitative transport, reminiscent of activities identified by earlier physiological studies. Moreover, recent expansion in the number of available amino acid transporter sequences have revealed evolutionary relationships between amino acid exporters from other organisms with a number of uncharacterized plant proteins, some of which might also function as amino acid exporters. In addition, genes that may regulate export of amino acids have been discovered. Studies of these putative transporter and regulator proteins may help in understanding the elusive molecular mechanisms of amino acid export in plants.

关键词： Nitrogen amino acids membrane transport.

SARS-CoV-2 triggers Dickkopf-1(Dkk-1)modulation of T helper cells and lung pathology in mice

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Genes & Diseases 2024年第4期11卷 9-12页

作者： Yifan Wu Freedom M.Green Stephen A.Shaw Lauren J.Bonilla Shannon E.Ronca Maria Elena Bottazzi Farrah Kheradmand Jill E.Weatherhead Department of Pathology&Immunology One Baylor PlazaHoustonTX 77030USA Department of Pediatrics One Baylor PlazaHoustonTX 77030USA Department of Medicine One Baylor PlazaHoustonTX 77030USA National School of Tropical Medicine One Baylor PlazaHoustonTX 77030USA Molecular Virology&Microbiology One Baylor PlazaHoustonTX77030USA Biologyof Inflammation Center Baylor College of MedicineOne BaylorPlazaHoustonTX77030USA Michael E.DeBakey va Center for Translational Research on Inflammatory Diseases HoustonTX 77030USA

Severe acute respiratory syndrome coronavirus 2(SARSCov-2)is the etiologic agent of the coronavirus disease 19(COVID-19)*** viral infections like SARS-CoV-2,a robust anti-viral type 1 immune response,including upregulation of type 1 CD4+T helper cells(Th1),is required for effective viral clearance while minimizing end-organ pathology and collateral tissue damage.

关键词： pathology acute respiratory

Stable oligonucleotide-functionalized gold nanosensors for environmental biocontaminant monitoring

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Journal of Environmental Sciences 2017年第12期29卷 49-59页

作者： Maria V.Riquelme Weinan Leng Marcos Carzolio Amy Pruden Peter Vikesland Via Department of Ciuil ancl Environmental Engineering Virginia TechBlacksburgVA 24061United States Department of Statistics Virginia TechBlacksburgVA 24061United States

The global propagation of environmental biocontaminants such as antibiotic resistant pathogens and their antibiotic resistance genes（ARGs） is a public health concern that highlights the need for improved monitoring strategies. Here, we demonstrate the environmental stability and applicability of an oligonucleotide-functionalized gold nanosensor. The mec A ARG was targeted as model biocontaminant due to its presence in clinically-relevant pathogens and to its emergence as an environmental *** A-specific nanosensors were tested for antibiotic resistance gene（ARG） detection in ARG-spiked effluent from four wastewater treatment plants（WWTPs）. The mec A-specific nanosensors showed stability in environmental conditions and in high ionic strength（[MgCl_2] 〈 50 m M）, and high selectivity against mismatched targets. Spectrophotometric detection was reproducible with an LOD of 70 pM（≈ 4 × 10~7 genes/μL）, even in the presence of interferences associated with non-target genomic DNA and complex WWTP effluent. This contribution supports the environmental applicability of a new line of cost-effective, field-deployable tools needed for wide-scale biocontaminant monitoring.

关键词： Stable oligonucleotide-functionalized gold nanosensors for environmental biocontaminant monitoring LOD DNA

CD40 stimulation as a molecular adjuvant for cancer vaccines and other immunotherapies

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Cellular & Molecular Immunology 2022年第1期19卷 14-22页

作者： Timothy N.J.Bullock Department of Pathology University of VirginiaCharlottesvilleVAUSA

The substantial advances attained by checkpoint blockade immunotherapies have driven an expansion in the approaches used to promote T cell access to the tumor microenvironment to provide targets for checkpoint *** in any T cell response to a tumor antigen is the capacity of dendritic cells to initiate and support such ***,the rationale and early immunobiology of CD40 as a master regulator of dendritic cell activation is reviewed,with further contextualization and appreciation for the role of CD40 stimulation not only in cancer vaccines but also in other contemporary immune-oncology approaches.

关键词： CD40 vaccine CD40L T cell dendritic cell

Involvement of autophagy in alcoholic liver injury and hepatitis C pathogenesis

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World Journal of Gastroenterology 2011年第20期17卷 2507-2514页

作者： Natalia A Osna Paul G Thomes Terrence M Donohue University of Nebraska Medical Center VA Medical Center

This review describes the principal pathways of macroautophagy (i.e. autophagy), microautophagy and chaperone-mediated autophagy as they are currently known to occur in mammalian cells. Because of its crucial role as an accessory digestive organ, the liver has a particularly robust autophagic activity that is sensitive to changes in plasma and dietary components. Ethanol consumption causes major changes in hepatic protein and lipid metabolism and both are regulated by autophagy, which is significantly affected by hepatic ethanol metabolism. Ethanol exposure enhances autophagosome formation in liver cells, but suppresses lysosome function. Excessive ethanol consumption synergizes with hepatitis C virus (HCV) to exacerbate liver injury, as alcohol-consuming HCV patients frequently have a longer course of infection and more severe manifestations of chronic hepatitis than abstinent HCV patients. Alcohol-elicited exacerbation of HCV infection pathogenesis is related to modulation by ethanol metabolism of HCV replication. Additionally, as part of this mechanism, autophagic proteins have been shown to regulate viral (HCV) replication and their intracel-lular accumulation. Because ethanol induces autophagosome expression, enhanced levels of autophagic proteins may enhance HCV infectivity in liver cells of alcoholics and heavy drinkers.

关键词： Autophagy Iysosome Autophagosome Hepatitis C virus Hepatitis C virus replication cycle Ethanol