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Characterization of colonic dendritic cells in normal and colitic mice

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World journal of Gastroenterology 2005年第40期11卷 6338-6347页

作者： Sheena m Cruickshank Nicholas r English Peter j Felsburg Simon r Carding Institute of molecular and Cellular Biology Antigen Presentation research Group Department of Clinical Science

AIm： recent studies demonstrating the direct involvement of dendritic cells （DC） in the activation of pathogenic T cells in animal models of inflammatory bowel disease identify DC as important antigen presenting cells in the colon. However, very little is known about the properties of colonic DC. mETHODS： Using immunohistochemistry, electron microscopy and flow cytometry we have characterized and compared colonic DC in the colon of healthy animals and interleukin-2-deficient （IL2-/-） mice that develop colitis. rESULTS： In the healthy colon, DC resided within the lamina propria and in close association with the basement membrane of colonic villi. Type i myeloid （CD11c^＋, CD11b^＋, B220, CD8） DC made up the largest （40-45%） population and all DC expressed low levels of CD80, CD86, and CD40, and had high endooltic activity consistent with an immature phenotype. In colitic IL2-/- mice, colonic DC numbers increased four- to five-fold and were localized within the epithelial layer and within aggregates of T and B cells. They were also many more DC in mesenteric lymph nodes （mLN）. The m.j.r.ty （〉85%） of DC in the colon and mLN of IL2./ mice were type 1 myeloid, and expressed high levels of mHC class II, CD80, CD86, CD40, DEC 205, and CCr5 molecules and were of low endocytic activity consistent with mature DC. CONCLUSION： These findings demonstrate striking changes in the number, distribution and phenotype of DC in the inflamed colon. Their intimate association with lymphocytes in the colon and draining lymph nodes suggest that they may contribute directly to the ongoing inflammation in the colon.

关键词： Colonic dendritic cells Interleukin 2 Colitis

Analysis of antisym metric cross-ply laminates using high-order shear deformation theories:a meshless approach

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Acta mechanica Sinica 2020年第5期36卷 1078-1098,I0003页

作者： D.E.S.rodrigues j.Belinha L.m.j.S.Dinis r.m.Natal jorge Institute of Science and Innovation in mechanical and Industrial Engineering 4200-465 PortoPortugal Department of mechanical Engineering School of EngineeringPolytechnic of Porto(ISEP)4200-072 PortoPortugal Department of mechanical Engineering Faculty of EngineeringUniversity of Porto(FEUP)4200-465 PortoPortugal

For many years finite element method(FEm)was the chosen numerical method for the analysis of composite ***,in the last 20 years,the scientific community has witnessed the birth and development of several meshless methods,which are more flexible and equally accurate numerical *** meshless method used in this work is the natural neighbour radial point interpolation method(NNrPIm).In order to discretize the problem domain,the NNrPIm only requires an unstructured nodal ***,using the Voronoi mathematical concept,it enforces the nodal connectivity and constructs the background integration *** NNrPIm shape functions are constructed using the radial point interpolation *** this work,the displacement field of composite laminated plates is defined by high-order shear deformation *** the end,several antisymmetric cross-ply laminates were analysed and the NNrPIm solutions were compared with the *** obtained results show the efficiency and accuracy of the NNrPIm formulation.

关键词： Antisymmetric cross-ply laminates High-order shear deformation theories meshless methods Naturalneighbour radial point interpolation method(NNrPIm)

Turbulent Inlet Conditions modeling using Large-eddy Simulations

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Computer modeling in Engineering & Sciences 2015年第2期104卷 105-132页

作者： m.m.r.Damasceno j.m.Vedovoto A.da Silveira-Neto UFU UberlandiaMGBrazil

Turbulence is a phenomenon which presents peculiarities when it is experimented or *** occurs due to its complexity and high sensibility to the inlet conditions of the turbulent flow fields,as well as the presence of a large range of time and length scales.A simplification for this situation is obtained with the use of approximations and turbulence *** the present work,the Largeeddy Simulations methodology was applied,aiming the modeling of the previously mentioned complexity,which consists in using a filter to resolve the large scales while the remaining scales were determined by classical and dynamic Smagorinsky *** different approximations for the inlet conditions were applied:white noise,random Flow Generation(rFG)and Synthetic Eddy method(SEm).It was possible to realize that the use of the dynamic Smagorinky model and the rFG or SEm methodologies resulted in a better characterization of the studied flow.

关键词： turbulent inlet conditions turbulence models large-eddy simulations

Adaptive Window Based 3-D Feature Selection for multispectral Image Classification Using Firefly Algorithm

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Computer Systems Science & Engineering 2023年第1期44卷 265-280页

作者： m.rajakani r.j.Kavitha A.ramachandran Full Time research Scholar Department of Electronics and Communication EngineeringUniversity College of EngineeringPanruti607106India Department of Electronics and Communication Engineering University College of EngineeringPanruti607106India Department of Computer Science and Engineering University College of EngineeringPanruti607106India

Feature extraction is the most critical step in classification of multispectral *** classification accuracy is mainly influenced by the feature sets that are selected to classify the *** the past,handcrafted feature sets are used which are not adaptive for different image *** overcome this,an evolu-tionary learning method is developed to automatically learn the spatial-spectral features for classification.A modified Firefly Algorithm(FA)which achieves maximum classification accuracy with reduced size of feature set is proposed to gain the interest of feature selection for this *** extracting the most effi-cient features from the data set,we have used 3-D discrete wavelet transform which decompose the multispectral image in all three *** selecting spatial and spectral features we have studied three different approaches namely overlapping window(OW-3DFS),non-overlapping window(NW-3DFS)adaptive window cube(AW-3DFS)and Pixel based *** multiclass Support Vector machine(mSVm)is used for classification *** con-ducted on madurai LISS IV multispectral image exploited that the adaptive win-dow approach is used to increase the classification accuracy.

关键词： multispectral image modifiedfireﬂy algorithm 3-D feature extraction feature selection multiclass support vector machine classification

Overcoming maladaptive plasticity through plastic compensation

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Current Zoology 2013年第4期59卷 526-536页

作者： matthew r.j. mOrrIS Sean m. rOGErS Department of Biological Sciences University of Calgary Calgary AB Canada T2N 1N4

most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plas- ticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes （standing genetic variation, genetic compensation） and two of which do not （standing epigenetic variation, plastic compensation）. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for under- standing evolutionary change

关键词： Homeostasis Canalization Ecological speciation Standing genetic variation Genetic compensation Countergradi-ent variation

rescattering of stimulated raman side scattering in nonuniform plasmas

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matter and radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.Chen W.B.Yao C.Z.Xiao j.F.myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

rescattering of stimulated raman side scattering(SrSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SrSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SrSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SrSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SrSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Selenoprotein expression is regulated at multiple levels in prostate cells

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Cell research 2006年第12期16卷 940-948页

作者： Cheryl m rebsch Frank j Penna Ⅲ Paul r Copeland Department of molecular Genetics Microbiology and immunology Department of molecular Genetics Microbiology and immunologyThe Cancer Institute of New JerseyUMDNJ-Robert Wood Johnson Medical School675 Hoes LanePiscatawayNJ 08854USA

Selenium supplementation in a population with low basal blood selenium levels has been reported to decrease theincidence of several cancers including prostate *** on the clinical findings,it is likely that the antioxidantfunction of one or more selenoproteins is responsible for the chemopreventive effect,although low molecular weightseleno-compounds have also been posited to selectively induce apoptosis in transformed *** address the effects ofselenium supplementation on selenoprotein expression in prostate cells,we have undertaken an analysis of antioxidantselenoprotein expression as well as selenium toxicity in non-tumorigenic prostate epithelial cells(rWPE-1)and prostatecancer cells(LNCaP and PC-3).Our results show that two of the glutathione peroxidase family members(GPX1 andGPX4)are highly induced by supplemental selenium in prostate cancer cells but only slightly induced in rWPE-1 *** addition,GPX1 levels are dramatically lower in PC-3 cells as compared to rWPE-1 or LNCaP ***2 proteinand mrNA,however,are only detectable in rWPE-1 *** the three selenium compounds tested(sodium selenite,sodium selenate and selenomethionine),only sodium selenite shows toxicity in a physiological range of *** and in contrast to previous studies,rWPE-1 cells were significantly more sensitive to selenitethan either of the prostate cancer cell *** results demonstrate that selenoproteins and selenium metabolism areregulated at multiple levels in prostate cells.

关键词： prostate selenium selenoproteins glutathione peroxidase selenocysteine

Differences in sensitivity of native and exotic fish species to changes in river temperature

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Current Zoology 2011年第6期57卷 852-862页

作者： r.S.E.W. LEUVEN A.j. HENDrIKS m.A.j. HUIjBrEGTS H.j.r. LENDErS j. mATTHEWS VAN DEr VELDE radboud University Nijmegen Institute for Water and Wetland Research Department of Environmental Science Heyendaal- seweg 135 NL-6525 AJ Nijmegen The Netherlands radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 NL-2300 RA Leiden The Netherlands

This paper describes the effects that temperature changes in the rhine river distributaries have on native and exotic fish diversity. Site-specific potentially affected fractions （PAFs） of the regional fish species pool were derived using species sensitivity distributions （SSDs） for water temperature. The number of fish species in the river distributaries has changed remarkably over the last century. The number of native rheophilous species declined up until 1980 due to anthropogenic disturbances such as commercial fishing, fiver regulation, migration barriers, habitat deterioration and water pollution. In spite of progress in river re- habilitation, the native rheophilous fish fauna has only partially recovered thus far. The total number of species has strongly in- creased due to the appearance of more exotic species. After the opening of the rhine-main-Danube waterway in 1992, many fish species originating from the Ponto-Caspian area colonized the rhine basin. The yearly minimum and maximum river tempera- tures at Lobith have increased by circa 4 ~C over the period 1908-2010. Exotic species show lower PAFs than native species at both ends of the temperature range. The interspecific variation in the temperature tolerance of exotic fish species was found to be large. Using temporal trends in river temperature allowed past predictions of PAFs to demonstrate that the increase in maximum river temperature negatively affected a higher percentage of native fish species than exotic species. Our results support the hy- pothesis that alterations of the river rhine＇s temperature regime caused by thermal pollution and global wanning limit the full recovery of native fish fauna and facilitate the establishment of exotic species which thereby increases competition between native and exotic species. Thermal refuges are important for the survival of native fish species under extreme summer or winter temperature conditions

关键词： Aquatic invaders Global warming Heat discharges Lethal temperature river rhine Thermal heterogeneity

Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher michael j.Lamonte Andrea Z.LaCroix Eleanor m.Simonsick Steven P.Hooker Humberto Parada jr. john Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(mL),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several mL VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVm)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:measured VO_(2max)is a strong predictor of *** mL can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology mortality