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Journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo R g Barrocas william M Landing Robert J M Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

From thermal conductive to thermal insulating:Effect of carbon vacancy content on lattice thermal conductivity of ZrC_(x)

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Journal of Materials Science & Technology 2021年第23期82卷 105-113页

作者： Yue Zhou william.g.Fahrenholtz Joseph graham gregory E.Hilmas Department of Materials Science and Engineering Missouri University of Science and TechnologyRollaMO 65409USA

Lattice thermal conductivities of zirconium carbide(ZrC_(x),x=1,0.75 and 0.5)ceramics with different carbon vacancy concentrations were calculated using a combination of first-principles calculations and the Debye-Callaway *** gruneisen parameters,Debye temperatures,and phonon group velocities were deduced from phonon dispersions of ZrC_(x) determined using first-principles *** addition,the effects of average atomic mass,grain size,average atomic volume and Zr isotopes on the lattice thermal conductivities of ZrC_(x) were analyzed using phonon scattering *** lattice thermal conductivity decreased as temperature increased for ZrC,ZrC_(0.75) and ZrC_(0.5)(Zr2 C),and decreased as carbon vacancy concentration ***,ZrC_(x) can be tailored from a thermal conducting material for ZrC with high lattice thermal conductivity to a thermal insulating material for ZrC_(0.5) with low lattice thermal ***,it opens a window to tune the thermal properties of ZrC_(x) by controlling the carbon vacancy content.

关键词： Zirconium carbide Lattice thermal conductivity Theoretical study First-principle calculations

ALTERATION IN ENTEROCYTE gENE EXPRESSION MAY EXPLAIN STRUCTURAL AND FUNCTIONAL CHANgES FOLLOWINg gLUTAMINE SUPPLEMENTED PARENTERAL NUTRITION

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Chinese Medical Sciences Journal 1999年第2期14卷 112-116页

作者： JiangZhuming,MD LiuYuewu,MD,phd MaYongxian,MD BaiManxi,MD,phd QiangBoqing,phd RobertSmith,MD DepartmentofSurgery PekingUnionMedicalCollegeHospitalBeijing100730 MolecularBiologyLaboratoryofChineseAcademyofMedicalSciences Beijing100730 JoslinDiabeticCenter DepartmentofSurgeryMassachusettsGeneralHospitalandBrighamandWomen＇sHospitalHarvardMedicalSchool

Following extensive bowel resection, the intestinal tract undergoes a variety of adaptive responses to enhance bowel function. The purpose of this study was to determine the effect of glutamine-supplemented parenteral nutrition on mucosal cellularity and gut function. In addition, enterocyte gene expression of two relevant systems was also characterized and related to the structural and functional changes that occurred. Male Wistar rats underwent a 60% small bowel resection and jugular vein catheterization and were randomized into two groups. The control group (n = 10) received a standard intravenous nutritional solution and the study group (n = 10) received a similar solution but enriched with alanylglutamine dipeptide. After 7 days blood was taken for amino acid analysis, and bowel was harvested to determine mucosal morphology and expression of mucosal cell glutaminase and IgF-I mRNA. Mesentery lymphnodes were cultured to determine the presence of bacteria and thus access bacteria translocation. Serum glutamine concentration and mucosal architecture were maintained in the study group compared to the controls. Seventy percent of lymphnodes were cultured positive in control vs. only 20% in the study group (P

关键词： Parenteral Nutrition Animals Dipeptides Enterocytes gene Expression glutaminase Ileum Insulin-Like growth Factor I Intestinal Mucosa Intestine, Small Jejunum Male RNA, Messenger Rats Rats, Wistar Research Support, Non-U.S. gov't

A carbon- and oxygen-isotope record of recent environ- mental change from Qinghai Lake, NE Tibetan Plateau

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Chinese Science Bulletin 2003年第14期48卷 1463-1468页

作者： A.C.g.henderson J.A.Holmes ZHANgJiawu M.J.Leng L.R.Carvalho EnvironmentalChangeResearchCentre(ECRC) DepartmentofGeographyUniversityCollegeLondon26BedfordWayLondonWC1H0APUK CenterforAridEnvironmentandPaleoclimateResearch NationalLaboratoryofWesternChina'sEnvironmentalSystemsLanzhouUniversityLanzhou730000China NERCIsotopegeosciencesLaboratory(NIgL) BritishGeologicalSurveyKeyworthNottingham.NG125GGUK Presentaddress:CentreforEcologyandHydrology(CEH) EdinburghBushEstatePenicuikMidlothianEH260OB.UK

A c. 300-year oxygen and carbon isotope record derived from fine-grained and ostracod carbonate from Qinghai Lake testifies to dramatic interannual tointerdecadal limnological change. Fine-grained carbonates, which are mainly authigenic, are likely to have formed in the epilimnion of the lake and their isotopic composition reflects the summer temperature and, more importantly, the isotopic composition of the near-surface waters, which is mainly a function of evaporative concentration. Ostracod shells are secreted in the benthos of the lake, and their isotopic composition reflects summer bottom-water conditions, together with fractionation effects, which may differ between species. Differences betweencontemporaneous values from authigenic carbonates and ostracod shells may provide an indication of stratification within the lake and variations in effective precipitation over the northeast part of the Tibetan Plateau over the past 300 years. A period of moderate evaporative concentration, from about 300 to 100 yr BP, was interrupted by a marked wet phase from ～100 to 40 yr BP, which was in turnfollowed by a return to drier conditions in the most recent part of the *** increase in ? 18O values in the latter part of the record accords well withinstrumental records of lake-level lowering and salinity increase since about 1955 AD.

关键词：中国西藏东北部环境变化碳同位素氧同位素季风古气候青海湖

ShapeShifter： a novel approach for identifying and quantifying stable lariat intronic species in RNAseq data

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Frontiers of Electrical and Electronic Engineering in China 2018年第3期6卷 267-274页

作者： Allison J Taggart william.g.Fairbrother Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRI 02912USA Center for Computational Molecular Biology Brown UniversityProvidenceRI 02912USA

Background： Most intronic lariats are rapidly turned over after splicing. However, new research suggests that some introns may have additional post-splicing functions. Current bioinformatics methods used to identify lariats require a sequencing read that traverses the lariat branchpoint. This method provides precise branchpoint sequence and position information, but is limited in its ability to quantify abundance of stabilized lariat species in a given RNAseq sample. Bioinformatic tools are needed to better address these emerging biological questions. Methods： We used an unsupervised machine learning approach on sequencing reads from publicly available ENCODE data to learn to identify and quantify lariats based on RNAseq read coverage shape. Results： We developed ShapeShifter, a novel approach for identifying and quantifying stable lariat species in RNAseq datasets. We learned a characteristic ＂lariat＂ curve from ENCODE RNAseq data and were able to estimate abundances for introns based on read coverage. Using this method we discovered new stable introns in these samples that were not represented using the older, branchpoint-traversing read method. Conclusions： ShapeShifter provides a robust approach towards detecting and quantifying stable lariat species.

关键词： splicing RNA lariat

Assessing gully erosion and rehabilitation using multi temporal LiDAR DEMs:Case study from the great Barrier Reef catchments,Australia

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International Soil and Water Conservation Research 2024年第1期12卷 184-199页

作者： Sana Khan Rebecca Bartley Anne Kinsey-henderson Aaron Hawdon The Commonwealth Scientific and Industrial Research Organisation(CSIRO) Environment1 James Cook DrDouglas4814Australia The Commonwealth Scientific and Industrial Research Organisation(CSIRO) EnvironmentGPO Box 2583BrisbaneQLD4001Australia

Millions of dollars are being spent on gully rehabilitation to help reduce excess fine sediment delivery to the great Barrier Reef(gBR).There is an urgent need for(i)prioritisation of active gullies for rehabilitation and(ii)the development of methodologies to inform the effectiveness of *** this study we analyse DEMs of Difference derived from 0.5 m resolution 2-3 year interval multi-temporal LiDAR data collected pre and post rehabilitation at three variable gully morphologies in the Burdekin *** analysis indicates that the highest annual average fine sediment erosion rates for the untreated control gullies occur at the linear gully(53.38 t ha^(-1)y^(-1))followed by linear-alluvial gully(34.24 t ha^(-1)y^(-1))and least at the alluvial gully(14.41 t ha^(-1)y^(-1)).The proportional loss or export of fine sediment from the gullies in their un-treated condition ranges from∼68 to 90%of what is eroded,and when the gullies are treated the proportion of fine sediment that is retained in the gully proportional to what is eroded increases to∼60%at all *** pre-treatment baseline erosion rates,and additional post treatment LiDAR captures,it is difficult to quantify the treatment *** results offer insights in the erosion mechanisms within different geomorphic gully morphologies and rehabilitation effects in these erosional *** study provides crucial knowledge of gully dynamics that can be coupled with other lines of evidence for better prioritisation of rehabilitation in the gBR catchments.

关键词： Digital elevation models (dis)connectivity Restoration geomorphic change detection geomorphic effectiveness gIS

Localized treatments using commercial dust and liquid formulations of fipronil against Coptotermes formosanus （Isoptera： Rhinotermitidae） in the laboratory

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Insect Science 2014年第2期21卷 174-180页

作者： Bal K. gautam gregg henderson Cai Wang Department of Entomology Louisiana State University LA 70803 USA

Use of proper application methods and formulations of termiticides are im- portant to reduce their negative impact to the environment. In this study, we conducted laboratory experiments to determine the effect of localized treatments with commercial dust and liquid formulations of fipronil against Formosan subterranean termites, Coptoter- mes formosanus Shiraki. The test arena consisted of a specially designed 16-chambered structure with a center chamber connected to 5 foraging chambers that themselves were connected to 10 additional foraging chambers. One peripheral chamber received a liquid or dust treatment and termites were released in the center chamber. Results showed that 〉 91% of the termites were dead within the 9-d test period despite the localized treatment of only 1 foraging chamber. Termites that were still alive after 9 d were transferred to an untreated dish and held for 10 more days. The majority of those termites were dead and the rest were moribund on day 19. Regardless of the specific dish treated, both formulations of fipronil were found to be highly efficacious. Termites did not exhibit repellency to either formulation. Our results suggest that localized （or spot） treatment with either commer- cially available dust or liquid formulations of fipronil can be a viable option for control of a termite infestation where complete soil drenching is not desirable.

关键词： Formosan subterranean termites nonrepellent termiticide soil treatment,spot treatment termite control

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural Regeneration Research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam M.R.groh Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton g.R.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Comparison of closure measurements with finite element model results in an underground coal mine in central Utah

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International Journal of Mining Science and Technology 2019年第1期29卷 9-15页

作者： william.g.Pariseau Michael K.McCarter Jessica M.Wempen Department of Mining Engineering University of Utah

Quantitative analysis of mine-wide subsidence at the kilometer scale and details of stress distribution about an advancing longwall face are estimated using an adaptation of the finite element method. The method is well suited to the tasks at hand. For greater realism, variability of strata properties is taken into account as are the effects of joints and cleats on elastic moduli and strengths. Evolution of pillar stress and entry closure remote from the face is readily quantified in a series of analyses that simulate face advance. Computed results compare favorably with the evolution of closure measurements about an instrumented pillar in a two-entry headgate. The appropriateness of the finite element method is confirmed. This method is based on first principles that avoid empirical schemes of uncertain applicability and numerical models ‘‘calibrated" by fitting computer output to mine measurements.

关键词： Finite element modeling Longwall mining Mine subsidence Stress modeling

Recycled asphalt shingle modified asphalt mixture design and performance evaluation

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 205-214页

作者： He Wang Punyaslok Rath william.g.uttlar Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Department of Civil and Environmental Engineering University of MissouriColumbiaMO 65211USA

The inclusion of recycled asphalt shingles(RAS)in asphalt mixtures has become increasingly common;however,the underlying design principles vary significantly by *** primary objectives of this study included:(1)evaluating the‘binder availability’concept for RAS mixtures through a carefully designed laboratory experiment;(2)demonstrating a balanced mixture performance testing approach for the design of RAS mixtures;and(3)evaluating the field data of RAS mixtures placed in the Midwest region of the *** asphalt mixture designs with RAS contents of 0,2.5%and 5.0%,which were designed to have nearly identical volumetric characteristics,were *** binder availability was determined to be approximately 100%in the two RAS mixtures *** addition,Hamburg wheel tracking and disk-shaped compact tension tests were conducted to evaluate the high-and low-temperature mixture *** expected,the addition of RAS significantly improved the rutting ***-shaped compact tension(DC(T))test results demonstrated that a soft base binder effectively permitted the design of thermal-crack-resistant RAS *** investigations indicated that the performance of pavement surfaces containing RAS was similar to that of surfaces containing only reclaimed asphalt pavement or virgin *** study also highlights a performanceengineered mix design approach,which is currently being adopted by several agencies in the Midwest(e.g.,Illinois Toll way,Missouri DOT,etc.)and can provide mix designers a reliable approach for designing innovative asphalt mixtures with higher recycling levels and a modern,heterogeneous ***,the proposed approach may prove to be a simpler,more mixture-centric alternative to the primary method suggested in AASHTO PP78-17,which recommends arbitrary VMA bumping plus binder extraction,recovery,and advanced binder testing.

关键词： Pavement Recycled asphalt shingles RAS DC(T) Cracking