检索结果-南通市图书馆

Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin g.Willson Lauren E.Cox Justin L.Hart Daniel C.Dey Department of geography University of AlabamaTuscaloosaAL 35487USA Department of Environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an EF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,pght penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Novel Single Switch High gain DC-DC Converter Topology for Renewable Energy Systems

引用

Energy Engineering 2021年第2期118卷 199-209页

作者： g.Indira Kishore M.Premkumar Ramesh Kumar Tripathi Chandra Sekhar Nalamati gMR Institute of Technology RajamSrikakulamAndhra Pradesh532127India Motilal Nehru National Institute of Technology AllahabadUttar Pradesh211004India

Renewable energy with sources such as photovoltaic(PV)or fuel cells can be utilized for the generation of elec-trical *** these sources generate fewer voltage values and therefore require high gain converters to match with DC bus voltage in *** high gain converters can be implemented with switched capacitors to meet the required DC bus *** capacitors operate in a series and parallel combination during switch-ing operation and produce high static gain,limits reverse voltage that appears across the components.A novel converter is proposed that satisfies all the features such as high voltage gain,only one switch,forces less potential stress cross the components,ripple current is *** features of the proposed converter are verified through MATLAB/SIMULINK.

关键词： DC-DC converter high gain renewable energy switched capacitors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Coupling virio-and bacterioplankton populations with environmental variable changes in the Bohai Sea

引用

Acta Oceanologica Sinica 2020年第6期39卷 72-83页

作者： Caixia Wang Lin Wu Yibo Wang James S.Paterson James g.Mitchell Xiaoke Hu Key Laboratory of Coastal Biology and Bioresource Utilization Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Ocean School Yantai UniversityYantai 264003China College of Science and Engineering Flinders UniversityAdelaideSA 5001Australia

Uncovering the role of environmental factors and finding critical factors which harbor significant fractions in governing microbial communities remain key questions in coastal marine *** detect the interactions between environmental factors and distributions of virio-and bacterioplankton in trophic coastal areas,we used flow cytometry to investigate the abundance of virio-and bacterioplankton covering 31 stations in the Bohai Sea of *** results suggested that the average abundance of total virus(TV)in winter(~2.29×108 particles/mL)was slightly lower than in summer(~3.83×108 particles/mL).The mean total bacterial abundance(TB)was much lower in winter(~2.54×107 particles/mL)than in summer(~5.43×107 particles/mL).Correlation analysis via redundancy analysis(RDA)and network analysis among virioplankton,bacterioplankton and environmental factors revealed that the abundances of viral and bacterial subpopulations depend on environmental *** winter,only temperature significantly influenced the abundances of virio-and *** summer,in addition to temperature,both salinity and nutrient(SiO2)had a remarkable impact on the distribution of virioand *** results showed a clear seasonal and trophic pattern throughout the whole water system,which revealed that temperature and eutrophication may play crucial roles in microbial distribution pattern.

关键词： virioplankton bacterioplankton flow cytometry network Bohai Sea

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MAT1 correlates with molecular subtypes and predicts poor survival in breast cancer

引用

Chinese Journal of Cancer Research 2018年第3期30卷 351-363页

作者： Hanxiao Xu Xianguang Bai Shengnan Yu Qian Liu Richard g Pestell Kongming Wu Department of Oncology Tongji Hospital of Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Medical School of Pingdingshan University Pingdingshan 467000 China Pennsylvania Center for Cancer and Regenerative Medicine Wynnewood PA 19096 USA

Objective：Menage a trois 1（MAT1）is a targeting subunit of cyclin-dependent kinase-activating kinase and general transcription factor IIH kinase,which modulates cell cycle,transcription and DNA *** dysregulation is responsible for diseases including *** further explore the role of MAT1 in breast cancer,we investigated the pathways in which MAT1 might be involved,the association between MAT1 and molecular subtypes,and the role of MAT1 in clinical outcomes of breast cancer ***：We conducted immunohistochemistry staining on tissue microarray and immunofluorescence staining on sections of MAT1 stable breast cancer ***,we performed Kyoto Encyclopedia of genes and genomes pathway analysis,correlation analysis and prognosis analysis on public ***：MAT1 was involved in multiple pathways including normal physiology signaling and disease-related ***,MAT1 positively correlated with the protein status of estrogen receptor and progesterone receptor,and was enriched in luminal-type and human epidermal growth factor receptor 2-enriched breast cancer in comparison with basal-like subtype at both m RNA and protein *** analysis revealed significant association between MAT1 m RNA amount and epithelial markers,mesenchymal markers,cancer stem cell markers,apoptosis markers,transcription markers and ***,the results of immunofluorescence stain indicated that MAT1 overexpression enhanced the protein abundance of epidermal growth factor receptor,vimentin,sex determining region Y-box 2 and sine oculis homeobox homolog ***,Kaplan-Meier Plotter analysis reflected that MAT1 could serve as a prognostic biomarker predicting worse relapse-free survival and metastasis-free ***：MAT1 is correlated with molecular subtypes and is associated with unfavorable prognosis for breast cancer patients.

关键词： Menage a trois 1(MAT1) breast cancer molecular subtypes prognosis proliferation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New Findings of Latest Early Olenekian(Early Triassic)Fossils in South Primorye,Russian Far East,and Their Stratigraphical Significance

引用

Journal of Earth Science 2021年第3期32卷 554-572页

作者： Yuri D.Zakharov Liana g.Bondarenko Alexander M.Popov Olga P.Smyshlyaeva Far Eastern geological Institute Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

Information on latest early Olenekian(latest Smithian)ammonoids is available apparently from only seven regions of the world,including South *** Smithian evidences on this topic are recorded from the West SMID(abbreviation from the Russian name of the quarry:"Building Materials and Details"),East SMID and golyj Cape areas in South *** provides additional information on systematic composition of latest Smithian ammonoid,as well as conodont and brachiopod assemblages from the recently identified Shimanskyites shimanskyi Zone,located between lower Olenekian Anasibirites nevolini Zone and upper Olenekian Tirolites subcassianus *** are many common ammonoid species in the Shimanskyites shimanskyi Zone and the underlying Anasibirites nevolini Zone,e.g.,Prosphingitoides sp.,Arctoceras septentrionale(Diener),Churkites syskoi Zakharov et Shigeta,Submeekoceras?subhhydaspis(Kiparisova),Prionites markevichi Zakharov et Smyshlyaeva,?Anasibirites?simanenkoi Zakharov et Smyshlyaeva,Xenoceltites?subvariocostatus Zakharov et Smyshlyaeva,and Mianwaliites zimini Zakharov et *** base of the Shimanskyites shimanskyi Zone,marked by a negativeδ13Corg excursion in the Kamenushka-2 Section by our previous study,coincides with the FO(first occurrence)of ammonoids Shimanskyites shimanskyi Zakharov et Smyshlyaeva and glyptophiceras ***(Waagen)and conodont Hindeodella budurovi *** zone is characterized additionally by some fossils common for the overlying upper Olenekian Tirolites subcassianus Zone:ammonoids of the genus Kamenushkaites,brachiopods Bittnerihyris margaritovi(Bittner)and Lepismatina *** conodont?Neogondolella?(=?Borinella)jubata *** latest Smithian ammonoids recorded from the Shimanskyites shimanskyi Zone totally consist of 30 taxa belonging to 11 families(Sageceratidae,Ussuiriidae,Aspenitidae,Paranannitidae,Arctoceratidae,Proptychitidae,?galfetitidae,Prionitidae,?Kashmiritidae,Xenoceltitidae and Palaeophyllitidae).Th

关键词： ammonoids conodonts brachiopods biostratigraphy Smithian Russia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A note on the estimation of variance for big BAF sampling

引用

Forest Ecosystems 2020年第4期7卷 819-832页

作者： Jeffrey H.gove Timothy g.gregoire Mark J.Ducey Thomas B.Lynch USDA Forest Service Northern Research Station271 Mast RoadDurham NH03824USA. School of Forestry&Environmental Studies Yale University360 Prospect StNew Haven CT06511USA. Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham NH03824USA. Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater OK74078USA.

Background:The double sampling method known as“big BAF sampling”has been advocated as a way to reduce sampling effort while still maintaining a reasonably precise estimate of volume.A well-known method for variance determination,Bruce’s method,is customarily used because the volume estimator takes the form of a product of random ***,the genesis of Bruce’s method is not known to most foresters who use the method in ***:We establish that the Taylor series approximation known as the Delta method provides a plausible explanation for the origins of Bruce’s *** were conducted on two different tree populations to ascertain the similarities of the Delta method to the exact variance of a ***,two alternative estimators for the variance of individual tree volume-basal area ratios,which are part of the estimation process,were compared within the overall variance estimation ***:The simulation results demonstrate that Bruce’s method provides a robust method for estimating the variance of inventories conducted with the big BAF *** simulations also demonstrate that the variance of the mean volume-basal area ratios can be computed using either the usual sample variance of the mean or the ratio variance estimators with equal accuracy,which had not been shown previously for Big BAF ***:A plausible explanation for the origins of Bruce’s method has been set forth both historically and mathematically in the Delta *** most settings,there is evidently no practical difference between applying the exact variance of a product or the Delta method—either can be used.A caution is articulated concerning the aggregation of tree-wise attributes into point-wise summaries in order to test the correlation between the two as a possible indicator of the need for further covariance augmentation.

关键词： Bitterlich sampling Delta method Double sampling Forest inventory Horizontal point sampling Variance of a product

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An approximate point-based alternative for the estimation of variance under big BAF sampling

引用

Forest Ecosystems 2021年第3期8卷 439-457页

作者： Thomas B.Lynch Jeffrey H.gove Timothy g.gregoire Mark J.Ducey Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA USDA Forest Service Northern Research Station271 Mast RoadDurham 03824NHUSA Yale School of Environment Yale University360 Prospect StNew Haven 06511CTUSA Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham 03824NHUSA

Background:A new variance estimator is derived and tested for big BAF(Basal Area Factor)sampling which is a forest inventory system that utilizes Bitterlich sampling(point sampling)with two BAF sizes,a small BAF for tree counts and a larger BAF on which tree measurements are made usually including DBHs and heights needed for volume ***:The new estimator is derived using the Delta method from an existing formulation of the big BAF estimator as consisting of three sample *** new formula is compared to existing big BAF estimators including a popular estimator based on Bruce’s ***:Several computer simulation studies were conducted comparing the new variance estimator to all known variance estimators for big BAF currently in the forest inventory *** simulations the new estimator performed well and comparably to existing variance ***:A possible advantage of the new estimator is that it does not require the assumption of negligible correlation between basal area counts on the small BAF factor and volume-basal area ratios based on the large BAF factor selection trees,an assumption required by all previous big BAF variance estimation *** this correlation was negligible on the simulation stands used in this study,it is conceivable that the correlation could be significant in some forest types,such as those in which the DBH-height relationship can be affected substantially by density perhaps through *** derived a formula that can be used to estimate the covariance between estimates of mean basal area and the ratio of estimates of mean volume and mean basal *** also mathematically derived expressions for bias in the big BAF estimator that can be used to show the bias approaches zero in large samples on the order of 1n where n is the number of sample points.

关键词： Bitterlich sampling Delta method Double sampling Estimator bias Forest inventory Horizontal point sampling Variance of a product Volume basal area ratio Covariance estimation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Intrahepatic vascular changes in non-alcoholic fatty liver disease: potential role of insulin-resistance and endothelial dysfunction

引用

World Journal of gastroenterology 2017年第37期23卷 6777-6787页

作者： Marcos Pasarín Juan g Abraldes Eleonora Liguori Beverley Kok Vincenzo La Mura Hepatic Hemodynamic Laboratory Liver UnitHospital ClinicIDIBAPS(Institut d'Investigacions Biomèdiques August Pi i Sunyer) University of Barcelona Cirrhosis Care Clinic Division of Gastroenterology(Liver Unit)CEGIIR University of Alberta Internal Medicine IRCCS San Donato Department of Biomedical Sciences for HealthUniversity of Milan

Metabolic syndrome is a cluster of several clinical conditions characterized by insulin-resistance and high cardiovascular risk. Non-alcoholic fatty liver disease is the liver expression of the metabolic syndrome, and insulin resistance can be a frequent comorbidity in several chronic liver diseases, in particular hepatitis C virus infection and/or cirrhosis. Several studies have demonstrated that insulin action is not only relevant for glucose control, but also for vascular homeostasis. Insulin regulates nitric oxide production, which mediates to a large degree the vasodilating, antiinflammatory and antithrombotic properties of a healthy endothelium, guaranteeing organ perfusion. The effects of insulin on the liver microvasculature and the effects of IR on sinusoidal endothelial cells have been studied in animal models of non-alcoholic fatty liver disease. The hypotheses derived from these studies and the potential translation of these results into humans are critically discussed in this review.

关键词：非酒精的脂肪肝疾病 Endothelial 机能障碍胰岛素抵抗新陈代谢的症候群

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tissue-specific Temporal Exome Capture Revealed Muscle-specific genes and SNPs in Indian Buffalo(Bubalus bubalis)

引用

genomics, Proteomics & Bioinformatics 2012年第2期10卷 107-113页

作者： Subhash J.Jakhesara Viral B.Ahir Ketan B.Padiya Prakash g.Koringa Dharamshibhai N.Rank Chaitanya g.Joshi Department of Animal Biotechnology College of Veterinary Science&Animal HusbandryAnand Agricultural UniversityAnand 388001India Department of Animal genetics and Breeding College of Veterinary Science&Animal HusbandryAnand Agricultural UniversityAnand 388001India

Whole genome sequencing of buffalo is yet to be completed, and in the near future it may not be possible to identify an exome （coding region of genome） through bioinformatics for designing probes to capture it. In the present study, we employed in solution hybridization to sequence tissue specific temporal exomes （TST exome） in buffalo. We utilized cDNA prepared from buffalo muscle tissue as a probe to capture TST exomes from the buffalo genome. This resulted in a prominent reduction of repeat sequences （up to 40%） and an enrichment of coding sequences （up to 60%）. Enriched targets were sequenced on a 454 pyro-sequencing platform, generating 101,244 reads contain- ing 24,127,779 high quality bases. The data revealed 40,100 variations, of which 403 were indels and 39,218 SNPs containing 195 nonsyn- onymous candidate SNPs in protein-coding regions. The study has indicated that 80% of the total genes identified from capture data were expressed in muscle tissue. The present study is the first of its kind to sequence TST exomes captured by use of cDNA molecules for SNPs found in the coding region without any prior sequence information of targeted molecules.

关键词： Hybridization Exome SNP, Bubalus bubalis Temporal gene expression 454 Sequencing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Uncertainty-aware Workflow for Keyhole Surgery Planning using Hierarchical Image Semantics

引用

Visual Informatics 2018年第1期2卷 26-36页

作者： Christina gillmann Robin g.C.Maack Tobias Post Thomas Wischgoll Hans Hagen University of Kaiserslautern Erwin-Schroedinger-Strasse 167663 Kaiserslautern Wright State University 3640 Colonel Glenn HwyDaytonOH

Keyhole surgeries become mcreasingly important in clinical daily routine as they help minimizing the damage of a patient's healthy *** planning of keyhole surgeries is based on medical imaging and an important factor that influences the surgeries**** to the image reconstruction process,medical image data contains uncertainty that exacerbates the planning of a keyhole *** this paper we present a visual workflow that helps clinicians to examine and compare different surgery paths as well as visualizing the patientsJ affected *** analysis is based on the concept of hierarchical image semantics,that segment the underlying image data with respect to the input images'uncertainty and the users understanding of tissue *** can define arbitrary surgery paths that they need to investigate *** defined paths can be queried by a rating function to identify paths that fulfill user-defined *** workflow allows a visual inspection of the affected tissues and its ***,the workflow includes a linked view system indicating the three-dimensional location of selected surgery paths as well as how these paths affect the patients *** show the effectiveness of the presented approach,we applied it to the planning of a keyhole surgery of a brain tumor removal and a kneecap surgery.

关键词： Wsual Analytics Workflow Uncertainty sualization Keyhole Surgery Planning

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：