检索结果-南通市图书馆

Tree wave migration across an elevation gradient in the Altai Mountains,Siberia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Mountain Science 2017年第3期14卷 442-452页

作者： Viacheslav I.KHARUK Sergei T.IM Maria L.DVINSKAYA kenneth j.ranson Il'ya A.PETROV Sukachev Institute of Forest SB RAS KrasnoyarskRussia Siberian Federal University KrasnoyarskRussia M.F.Reshetnev Siberian State Aerospace University KrasnoyarskRussia NASA's Goddard Space Flight Center GreenbeltMarylandUSA

The phenomenon of tree waves （hedges and ribbons） formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberian pine （Pinus sibirica） forms hedges on windward slopes and ribbons on the leeward ones. Hedges were formed by prevailing winds and oriented along winds direction. Ribbons were formed by snow blowing and accumulating on the leeward slope and perpendicular to the prevailing winds, as well as to the elevation gradient. Hedges were always linked with microtopography features, whereas ribbons were not. Trees are migrating upward by waves and new ribbons and hedges are forming at or near tree line, whereas at lower elevations ribbons and hedges are being transformed into dosed forests. Time series of high-resolution satellite scenes （from 1968 to 2OLO） indicated an upslope shift in the position ribbons averaged 155＋26 m （or 3-7 m yr^-1） and crown closure increased （about 35%-90%）. The hedges advance was limited by poor regeneration establishment and was negligible. Regeneration within the ribbon zone was approximately 2.5 times （5060 vs 2120 ha^-1） higher then within the hedges zone. During the last four decades, Siberian pine in both hedges and ribbons strongly increased its growth increment, and recent tree growth rate for 50 year-old trees was about twice higher than those recorded for similarly-aged trees at the beginning of the 20^th century. Hedges and ribbons are phenomena that are widespread within the southern and northern Siberian Mountains.

关键词： Ribbon forest Hedges Siberian forests Alpine treeline Tree waves Siberian pine AltaiMountains

Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik j.Persson Magnus Ekstrom Sean P.Healey Zhiqiang Yang johan Holmgren Eva Lindberg kenneth Nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson Ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

Circulating tumor cells shielded with extracellular vesicle-derived CD45 evade T cell attack to enable metastasis

在线全文

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第5期9卷 2114-2131页

作者： Chuan Yang Xueping Wang kenneth K.W.To Caimei Cui Min Luo Shaocong Wu Lamei Huang Kai Fu Can Pan Zeyu Liu Teng Fan Caibo Yang Fang Wang Liwu Fu State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060P.R.China School of Pharmacy Faculty of MedicineThe Chinese University of Hong KongHong KongChina LABVIV Technology(Shenzhen)Co. LtdShenzhen 518057China

Circulating tumor cells(CTCs)are precursors of distant metastasis in a subset of cancer patients.A better understanding of CTCs heterogeneity and how these CTCs survive during hematogenous dissemination could lay the foundation for therapeutic prevention of cancer *** remains elusive how CTCs evade immune surveillance and elimination by immune *** this study,we unequivocally identified a subpopulation of CTCs shielded with extracellular vesicle(EVs)-derived CD45(termed as CD45^(+)CTCs)that resisted T cell attack.A higher percentage of CD45^(+)CTCs was found to be closely correlated with higher incidence of metastasis and worse prognosis in cancer ***,CD45^(+)tumor cells orchestrated an immunosuppressive milieu and CD45^(+)CTCs exhibited remarkably stronger metastatic potential than CD45−CTCs in ***,CD45 expressing on tumor surfaces was shown to form intercellular CD45-CD45 homophilic interactions with CD45 on T cells,thereby preventing CD45 exclusion from TCR-pMHC synapse and leading to diminished TCR signaling transduction and suppressed immune ***,these results pointed to an underappreciated capability of EVs-derived CD45-dressed CTCs in immune evasion and metastasis,providing a rationale for targeting EVs-derived CD45 internalization by CTCs to prevent cancer metastasis.

关键词： CD45 metastasis prevention

Small-molecule agents for cancer immunotherapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第3期14卷 905-952页

作者： Fang Wang Kai Fu Yujue Wang Can Pan Xueping Wang Zeyu Liu Chuan Yang Ying Zheng Xiaopeng Li Yu Lu kenneth Kin Wah To Chenglai Xia jianye Zhang Zhi Shi Zeping Hu Min Huang Liwu Fu State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineGuangdong Esophageal Cancer InstituteGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China School of Pharmaceutical Sciences Tsinghua-Peking Center for Life SciencesBeijing Frontier Research Center for Biological StructureTsinghua UniversityBeijing 100084China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Department of Cell Biology&Institute of Biomedicine National Engineering Research Center of Genetic MedicineMOE Key Laboratory of Tumor Molecular BiologyGuangdong Provincial Key Laboratory of Bioengineering MedicineCollege of Life Science and TechnologyJinan UniversityGuangzhou 510632China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology NMPA and State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences and the Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhou 511436China School of Pharmacy The Chinese University of Hong KongHong Kong 999077China Affiliated Foshan Maternity and Child Healthcare Hospital Southern Medical UniversityFoshan 528000China

Cancer immunotherapy,exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy,is revolutionizing cancer *** induce long-term tumor regression and overall survival benefit in many types of *** the advances in our knowledge about the tumor immune microenvironment,remarkable progress has been made in the development of small-molecule drugs for *** molecules targeting PRR-associated pathways,immune checkpoints,oncogenic signaling,metabolic pathways,cytokine/chemokine signaling,and immune-related kinases have been extensively *** of smallmolecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor ***,we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.

关键词： Cancer immunotherapy Small-molecule agents Immune checkpoints Oncogenic signaling Metabolic pathways Cytokine/chemokine signaling Antitumor immunity Tumor immune microenvironment

Global wild rice germplasm resources conservation alliance:World Wild-Rice Wiring

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2024年第4期17卷 516-518页

作者： Xiaoming Zheng Disna Ratnasekera jiayu Fan Robert j.Henry Beng-Kah Song kenneth M.Olsen Bal Krishna joshi Maria Celeste N.Banaticla-Hilario Tonapha Pusadee Adane Getachew Melaku Yeyinou Laura Estelle Loko Koukham Vilayheuang Gavers K.Oppong Samuel Aduse Poku Peterson W.Wambugu Song Ge Aldo Merotto junior Ohn Mar Aung Ramaiah Venuprasad Ajay Kohli Wenbin Zhou Qian Qian National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Sanya National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesBeijing 100081China International Rice Research Institute DAPO Box 7777Metro Manila 4031Philippines Department of Agricultural Biology Faculty of AgricultureUniversity of RuhunaMatara 81000Sri Lanka Yazhouwan National Laboratory No.8 Huanjin RoadYazhou DistrictSanya CityHainan Province 572024China Hainan University Haikou 570228China ARC Centre of Excellence for Plant Success in Nature and Agriculture University of QueenslandBrisbaneQLD4072Australia School of Science Monash University Malaysia47500 Bandar SunwaySelangor 47500Malaysia Department of Biology Washington University in St.LouisSt.LouisMO 63130-4899USA National Agriculture Genetic Resources Center(Genebank) KhumaltarPO Box 3055KathmanduNepal Plant Biology Division Insttute of Biological SciencesUniversity of the Pilippines Los BanosLos BanosLaguna 4031Philippines Division of Agronomy Department of Plant and Soil SciencesFaculty of AgricultureChiang Mai UniversityChiang Mai 50200Thailand Bio and Emerging Technology Institute Addis Ababa 1165Ethiopia National University of Sciences TechnologiesEngineering and Mathematics(UNSTIM)Dassa-ZouméBP 14Benin National Genebank Rice and Cash Crops Research CenterNAFRIVientiane 0605Lao PDR Plant Sciences and the Bioeconomy Rothamsted ResearchHarpenden AL52JQUK UK Future Food Beacon of Excellence and School of Biosciences and University of Nottingham Nottingham LE125RDUK Department of Plant and Environmental Biology University of GhanaAccraGhana Kenya Agricultural and Livestock Research Organization Genetic Resources Research InstituteNairobi 00200Kenya Institute of Botany Chinese Academy of SciencesBeijing 100093China Federal University of Rio Grande do Sul UFRGSPorto Alegre 91501-970RSBrazil Department of Agricultur

Wild relatives of crop are key genetic resources serving as diversity reservoirs for crop improvement under changing ***(Oryza sativa)is one of the most important crops in the world,providing staple food for half of the world's *** rice is thus a critical germplasm resource for sustained global food security,ensuring high production yields,improved quality,and stress resistance in the face of climate *** rice is closely related to domesticated rice and has a rich genetic diversity and exceptional adaptability to extreme *** has played a pivotal role in the history of rice hybridization and has become a key resource for rice breeding *** identification of wild-type cytoplasmic male sterility resources paved the way for the achievement of the“three lines”goal in hybrid rice,leading to a significant increase in rice *** addition,the use of resistance alleles found in wild rice is making rice production more resilient to losses caused by environmental ***,wild rice germplasm resources are threatened due to habitat destruction and other anthropogenic *** the same time,the lack of centralized distribution of wild rice has hampered the sharing of basic information on wild rice resources and the utilization and conservation of wild rice in each country,as well as collaboration among scientists.

关键词： germplasm breeding crops

Diabetes mellitus as a risk factor for gastrointestinal cancer among American veterans

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World journal of Gastroenterology 2009年第42期15卷 5274-5278页

作者： M Mazen jamal Eugene j Yoon kenneth j Vega Mehrtash Hashemzadeh kenneth j Chang Division of Gastroenterology Veterans Affairs(VA) Medical CenterLong BeachCA 90822United States Division of Gastroenterology Department of Internal MedicineCollege of MedicineUniversity of CaliforniaIrvine Medical CenterOrangeCA 92868United States Division of Gastroenterology University of Florida/JacksonvilleJacksonvilleFL 32207United States

AIM:To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus(DM) .METHODS:Eligibility for this study included patients with type 2 DM(ICD-9 code 250.0) who were discharged from Department of Veteran Affairs hospitals between 1990 and ***-matched control patients without DM were selected from the same patient treatment files during the same *** information included age,sex and *** diagnoses included known risk factors based on their ICD-9 *** multivariate logistic regression,the occurrence of biliary and pancreatic cancer was compared between case subjects with DM and controls without ***:A total of 1172496 case and control subjects were *** mean age for study and control subjects was 65.8 ± 11.3 and 64.8 ± 12.6 years,*** frequency of pancreatic cancer in subjects with DM was increased(0.9%) in comparison to control subjects(0.3%) with an OR of 3.22(95% CI:3.03-3.42) .The incidence of gallbladder andextrahepatic biliary cancers was increased by twofold in diabetic patients when compared to *** OR and 95% CI were 2.20(1.56-3.00) and 2.10(1.61-2.53) ,***:Our study demonstrated that patients with DM have a threefold increased risk for developing pancreatic cancer and a twofold risk for developing biliary cancer.

关键词： Diabetes mellitus Pancreatic neoplasms Adenocarcinoma Gallbladder neoplasms

Power regulation of kinematic control inputs for forward flying Drosophila

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2014年第6期30卷 809-818页

作者： kenneth MacFarlane Imraan Faruque j.Sean Humbert 3181 Glenn L Martin Hall University of MarylandCollege Park MD 20742 USA

The choices of insect wing kinematic programs is not well understood,particularly the mechanism by which an insect selects a distortion to achieve flight control.A methodology to evaluate prospective kinematic control inputs is presented based on the reachable states when control actuation was constrained to a unit of *** method implements a computationally-derived reduced order model of the insect’s flight dynamics combined with calculation of power *** kinematic inputs are evaluated based on this criterion for a Drosophila size insect in forward *** bias is shown to be the dominant control input using this power normalized evaluation measure.

关键词： Flight control Control Drosophila Power

Intraocular lens power calculation in eyes with previous corneal refractive surgery

在线全文

学校读者我要写书评

暂无评论

Eye and Vision 2018年第1期5卷 172-181页

作者： Giacomo Savini kenneth j.Hoffer G.B.Bietti Eye Foundation RomeItaly. Stein Eye Institute University of CaliforniaLos AngelesCAUSA.3 St.Mary’s Eye CenterSanta MonicaCAUSA

Background:This review aims to explain the reasons why intraocular lens(IOL)power calculation is challenging in eyes with previous corneal refractive surgery and what solutions are currently available to obtain more accurate ***:After IOL implantation in eyes with previous LASIK,PRK or RK,a refractive surprise can occur because (i)the altered ratio between the anterior and posterior corneal surface makes the keratometric index invalid;(ii)the corneal curvature radius is measured out of the optical zone;and (iii)the effective lens position is erroneously predicted if such a prediction is based on the post-refractive surgery corneal *** methods are currently available to obtain the best refractive outcomes in these eyes,even when the perioperative data(*** corneal power and surgically induced refractive change)are not *** this review,we describe the most accurate methods based on our clinical ***:IOL power calculation after myopic corneal refractive surgery can be calculated with a variety of methods that lead to relatively accurate outcomes,with 60 to 70%of eyes showing a prediction error within 0.50 diopters.

关键词： Cataract Intraocular lens power LASIK PRK Excimer laser Corneal surgery Keratometry

Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris Koch kenneth j.Reimer Environmental Sciences Group Royal Military College of Canada

Fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a major compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the major arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus Fungi HPLC-ICP-MS XAS imaging