检索结果-南通市图书馆

Phylogenetic patterns of shrub communities along the longitudinal and latitudinal gradients on the northeastern Qinghai–Tibetan Plateau

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2020年第5期17卷 1106-1114页

作者： XIAO yuan-ming YANG Lu-cun nie Xiu-qing LI Chang-bin XIONG Feng ZHOU Guo-ying Northwest Institute of Plateau Biology Chinese Academy of SciencesXining 810008China Key Laboratory of Tibetan Medicine Research Chinese Academy of SciencesXining 810008China Qinghai Key Laboratory of Qinghai-Tibet Plateau Biological Resources Xining 810008China University of Chinese Academy of Sciences Beijing 100049China

Biodiversity distribution patterns are a basic and long-standing but crucial aspect of ecology research.These patterns form the primary source of data used to develop biodiversity protection practices,especially in mountain ecosystems.Shrubs comprise one of the main types of vegetation on the Qinghai–Tibetan Plateau,where they serve vital ecological functions.In this study,we used a community phylogenetic approach to examine the distribution patterns of shrub communities along the longitudinal and latitudinal gradients on the northeastern Qinghai–Tibetan Plateau.We observed significant latitudinal trends in both the phylogenetic diversity(PD)and net relatedness index(NRI)values of shrub communities,such that the former decreased and the latter increased with increasing latitude.However,no significant PD,NRI and nearest taxon index(NTI)distribution patterns were observed along a longitudinal gradient.A further analysis revealed that the combination of temperature-related and precipitation-related climate variables most strongly affected the PD,NRI and NTI values of shrub communities,indicating that the latitudinal patterns in the PD,NRI and NTI of a shrub community may be determined mainly by interactions with these climate factors.

关键词： Phylogenetic diversity Phylogenetic community structure Shrub communities Qinghai–Tibetan Plateau Net Relatedness Index Nearest Taxon Index

在线全文

学校读者我要写书评

暂无评论

双表型鼻腔鼻窦肉瘤8例临床病理分析

临床与实验病理学杂志 2020年第8期36卷 924-927页

作者：聂洪婷翟长文袁存存王纾宜复旦大学附属眼耳鼻喉科医院病理科上海200031

目的探讨双表型鼻腔鼻窦肉瘤(biphenotypic sinonasal sarcoma,BSNS)的临床病理特征、诊断、鉴别诊断。方法回顾性分析8例BSNS的临床病理、免疫表型特点,其中5例采用荧光原位杂交(fluorescence in situ hybridization,FISH)技术检测Pax-... 详细信息

目的探讨双表型鼻腔鼻窦肉瘤(biphenotypic sinonasal sarcoma,BSNS)的临床病理特征、诊断、鉴别诊断。方法回顾性分析8例BSNS的临床病理、免疫表型特点,其中5例采用荧光原位杂交(fluorescence in situ hybridization,FISH)技术检测Pax-3基因分离情况。结果8例BSNS中男性3例,女性5例;发病年龄26~74岁,中位年龄58岁。临床多表现为鼻塞、鼻出血、眼痛及面部肿胀等。眼观:肿瘤灰白色桑葚样。镜检:形态较一致的梭形细胞在黏膜上皮下呈浸润性生长,并牵拉表面上皮致上皮内陷,近上皮处细胞较密集;肿瘤细胞排列呈束状、鱼骨状,可侵犯骨组织;细胞核呈波浪状,胞质嗜伊红,坏死及核分裂象不明显。间质内可见血管外皮瘤样结构,伴有胶原变性。免疫表型:肿瘤细胞S-100(8/8)、Calponin(8/8)、MSA(7/8)、SMA(7/8)、FXⅢa(8/8)均阳性;Ki-67增殖指数较低(2%~5%)。5例Pax-3分离探针检测均呈阳性,支持BSNS的诊断。所有病例均获得随访,随访时间8~31个月,2例术后复发,6例未见复发。结论BSNS是一种具有神经及肌源性分化特征的低度恶性软组织肉瘤,并伴有Pax-3基因重排,结合形态、免疫表型及分子学改变可明确诊断。

关键词：软组织肿瘤鼻腔鼻窦肉瘤 Pax-3 双表型

Tidal Bore Dynamics Around the Similar Right-Angle Shoreline in the Qiantang Estuary,China

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2022年第5期36卷 827-838页

作者： WANG Qiu-shun PAN cun-hong CHEN Fu-yuan Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020China Zhejiang Provincial Key Laboratory of Estuary and Coast Hangzhou 310020China

Tidal bores are a unique hydrodynamic phenomenon during flood tide in the Qiantang Estuary.The tidal bore propagation around the similar right-angle shoreline is rarely documented in tidal estuaries.To investigate tidal bores around this shoreline,a hydrodynamic model combined with a theoretical method is employed to reveal the characteristics of the bore propagation.The theoretical solution of the tidal bore intensity is deduced to illustrate the relationship of the incident tidal bores and the back-flow bores during the propagation.The hydrodynamic model based on shallow water equation is employed to perform the simulation of tidal bores in the estuary.Model results with respect to the bore height and the propagation speed of tidal bores have a favourable agreement with field data.The tidal bore dynamics in the neighborhood of the similar right-angle shoreline are elucidated.The characteristics of tidal bores in terms of water surface,velocity,bore steepness and the intensity are illustrated and the back-flow bore is analyzed by numerical and theoretical methods around the similar right-angle shoreline.The height of the back-flow bore relative to the incident tidal bore ranges from 1.05 to 1.77.Model result reveals that the ambient water depth and the shape of the similar right-angle shoreline are contributed to the back-flow bore formation.

关键词： back-flow bore numerical model shallow water equation Qiantang Estuary tidal bores

A novel machine learning approach(svm Somatic) to distinguish somatic and germline mutations using next-generation sequencing data

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2021年第2期42卷 246-249页

作者： Yu-Fang Mao Xi-Guo yuan Yu-Peng cun School of Computer Science and Technology Xidian UniversityXi'anShaanxi 710071China iFlora Bioinformatics Center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

DEAR EDITOR,Somatic mutations are a large category of genetic variations,which play an essential role in tumorigenesis. Detection of somatic single nucleotide variants(SNVs) could facilitate downstream analysis of tumorigenesis. Many computational methods have been developed to detect SNVs, but most require normal matched samples to differentiate somatic SNVs from the normal state, which can be difficult to obtain.

关键词： data A novel machine learning approach svm Somatic

在线全文

学校读者我要写书评

暂无评论

红冬蛇菰提取物抗氧化及抑制亚硝化作用研究

天然产物研究与开发 2017年第12期29卷 2081-2086页

作者：张声源庄远杯罗铝铿陈一村聂华嘉应学院医学院梅州514031 汕头大学医学院汕头515041

对红冬蛇菰不同溶剂提取物的抗氧化活性及抑制亚硝化作用进行比较研究。采用DPPH法、ABTS法和普鲁士蓝法分别测定各提取物的自由基清除能力和铁离子还原力,以评价红冬蛇菰的抗氧化能力;采用盐酸萘乙二胺法和α-萘胺法分别测定红冬蛇菰... 详细信息

对红冬蛇菰不同溶剂提取物的抗氧化活性及抑制亚硝化作用进行比较研究。采用DPPH法、ABTS法和普鲁士蓝法分别测定各提取物的自由基清除能力和铁离子还原力,以评价红冬蛇菰的抗氧化能力;采用盐酸萘乙二胺法和α-萘胺法分别测定红冬蛇菰各提取物对亚硝酸盐的清除率和对亚硝胺合成的阻断率,以评价红冬蛇菰的抑制亚硝化作用。实验结果表明,红冬蛇菰各提取物中乙酸乙酯提取物清除DPPH自由基(IC_(50)=0.06±0.001 mg/mL)和ABTS自由基(IC_(50)=0.07±0.001 mg/mL)能力以及对铁离子还原能力最强,并显著强于其他提取物(P<0.01),其中清除ABTS自由基的能力显著高于Vc(IC_(50)=0.10±0.002 mg/mL)(P<0.01);在模拟人体胃液的条件下(pH 3.0,温度37℃),各提取物能有效地清除亚硝酸盐以及阻断亚硝胺合成,并随着反应质量浓度增加清除率和阻断率增大最后趋于平缓,其中乙酸乙酯提取物对亚硝酸盐的清除能力(IC_(50)=1.91±0.022 mg/mL)和亚硝胺合成的阻断能力(IC_(50)=8.44±0.091 mg/mL)均显著强于其他提取物(P<0.01)。红冬蛇菰提取物属天然产物,具有较好的抗氧化活性和抑制亚硝化作用,因此在抗氧化剂的研究方面具有潜在的开发利用价值,同时极有可能是一种新的防癌抗癌天然保健品。

关键词：红冬蛇菰抗氧化抑制亚硝化自由基 DPPH

Accuracy Comparison of Gridded Historical Cultivated Land Data in Jiangsu and Anhui Provinces

在线全文

学校读者我要写书评

暂无评论

Chinese Geographical Science 2017年第2期27卷 273-285页

作者： yuan cun YE Yu TANG Chanchan FANG Xiuqi School of Geography Beijing Normal UniversityBeijing 100875China Encyclopedia of China Publishing House Beijing 100037China Key Laboratory of Environment Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China

The spatial resolution of source data, the impact factor selection on the grid model and the size of the grid might be the main limitations of global land datasets applied on a regional scale. Quantitative studies of the impacts of rasterization on data accuracy can help improve data resolution and regional data accuracy. Through a case study of cropland data for Jiangsu and Anhui provinces in China, this research compared data accuracy with different data sources, rasterization methods, and grid sizes. First, we investigated the influence of different data sources on gridded data accuracy. The temporal trends of the History Database of the Global Environment(HYDE), Chinese Historical Cropland Data(CHCD), and Suwan Cropland Data(SWCD) datasets were more similar. However, different spatial resolutions of cropland source data in the CHCD and SWCD datasets revealed an average difference of 16.61% when provincial and county data were downscaled to a 10 × 10 km^2 grid for comparison. Second, the influence of selection of the potential arable land reclamation rate and temperature factors, as well as the different processing methods for water factors, on accuracy of gridded datasets was investigated. Applying the reclamation rate of potential cropland to grid-processing increased the diversity of spatial distribution but resulted in only a slightly greater standard deviation, which increased by 4.05. Temperature factors only produced relative disparities within 10% and absolute disparities within 2 km^2 over more than 90% of grid cells. For the different processing methods for water factors, the HYDE dataset distributed 70% more cropland in grid cells along riverbanks, at the abandoned Yellow River Estuary(located in Binhai County, Yancheng City, Jiangsu Province), and around Hongze Lake, than did the SWCD dataset. Finally, we explored the influence of different grid sizes. Absolute accuracy disparities by unit area for the year 2000 were within 0.1 km^2 at a 1 km^2 grid size, a 25% improvement over the 10 km^2 grid siz

关键词：精确性评估空间分辨率处理格子的方法格子尺寸历史的时期

在线全文

学校读者我要写书评

暂无评论

一类二维非局部椭圆问题的有限元方法

湘潭大学自然科学学报 2010年第3期32卷 9-12页

作者：周鸿旋喻海元聂存云闽江学院软件学院福建福州350011 湘潭大学数学与计算科学学院湖南湘潭411105 湖南工程学院理学院湖南湘潭411104

针对一类具有非局部边界的二维椭圆问题,利用微分方程的叠加原理,将方程化为带Dirichlet边界的非齐次方程和带积分边界的齐次方程,采用等参双线性有限元方法分别进行离散,得到该问题的有限元解;进一步,对相应有限元解进行误差分析,得到... 详细信息

针对一类具有非局部边界的二维椭圆问题,利用微分方程的叠加原理,将方程化为带Dirichlet边界的非齐次方程和带积分边界的齐次方程,采用等参双线性有限元方法分别进行离散,得到该问题的有限元解;进一步,对相应有限元解进行误差分析,得到其最优L2模估计,数值实验验证了理论结果的正确性.

关键词：非局部边界椭圆问题等参双线性有限元误差估计

Effect of acid phosphatase produced by Trichoderma asperellum Q1 on growth of Arabidopsis under salt stress

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2017年第6期16卷 1341-1346页

作者： ZHAO Lei LIU Qun ZHANG Ya-qing CUI Qing-yu LIANG yuan-cun Institute of Environment and Ecology Shandong Normal University Jinan 250014 P.R. China College of Life Science Shandong Normal University Jinan 250014 P.R. China College of Plant Protection Shandong Agricultural University Tai'an 271018 P.R. China

Salt stress is a major environmental factor that inhibits crop growth.Trichoderma spp.are the most efficient biocontrol fungi and some of the strains can stimulate plant growth.Phosphate solubilization is known as one of the main mechanisms in promoting plant growth,but the underlying mechanisms of phosphate solubilization in the salinity still need to be explored.The Trichoderma asperellum Q1 isolated and identified in our lab is a beneficial rhizosphere biocontrol fungus with a high phosphate solubilization activity.It could produce acid and alkaline phosphatases when using insoluble organic phosphorus as the sole phosphorus source,the salt stress increased the phosphorus-solubilization ability of the strain and the activities of the two enzymes.Furthermore,an acid phosphatase was purified from the fermentation broth by ammonium sulphate precipitation,ion-exchange,and gel filtration chromatography.Its molecular weight was 55 k Da as determined by SDS-PAGE.The purified acid phosphatase was used to investigate growth performance of Arabidopsis thaliana by plate assay and the result showed that it contributed to Arabidopsis growth by transforming organic phosphate into a soluble inorganic form under salt stress.To our knowledge,this is the first report on acid phosphatase purification from T.asperellum and its function in regulation of plant growth under salt stress.

关键词： Trichoderma asperellum Arabidopsis thaliana acid phosphatase plant-growth promotion salt stress

在线全文

学校读者我要写书评

暂无评论

全过程人民民主的理论演进与基本特征

江西财经大学学报 2023年第1期 3-11页

作者：肖存良袁峰复旦大学马克思主义学院上海200433 上海市委党校马克思主义学院上海200237

从马克思主义视野出发,全过程人民民主经历了自身的理论演进过程。马克思恩格斯指出,资产阶级民主属于有限民主,代替这种民主的新型民主应该将民主贯穿全部政治、经济和社会生活中。列宁在领导俄国革命过程中创立了苏维埃民主,并把党的... 详细信息

从马克思主义视野出发,全过程人民民主经历了自身的理论演进过程。马克思恩格斯指出,资产阶级民主属于有限民主,代替这种民主的新型民主应该将民主贯穿全部政治、经济和社会生活中。列宁在领导俄国革命过程中创立了苏维埃民主,并把党的领导与苏维埃民主建设有机复合。中国共产党继承了马克思主义民主理论,把民主贯穿政党、政治、经济和社会中,创立了全过程人民民主。全过程人民民主是一种复合民主,其实现离不开党的领导,需要把党的领导与人民民主有机复合。

关键词：全过程人民民主马克思主义人民民主