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Molecular Related Indexes Assessment and Traits Correlation Analysis of Turbot(Scophthalmus maximus L.) by Using SSR Marker Correlation Coefficient in Turbot
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作者 Yu MA Yulong HU +1 位作者 Liyong XU Weiji WANG 《Agricultural Science & Technology》 CAS 2014年第6期895-900,共6页
Five molecular related indexes: MOL, SIM, d2, H0and PIC of 15 turbot parent pairs were estimated by using 10 SSR loci, which were used in correlation analysis with growth traits, DIL and DIW, of family filial from tho... Five molecular related indexes: MOL, SIM, d2, H0and PIC of 15 turbot parent pairs were estimated by using 10 SSR loci, which were used in correlation analysis with growth traits, DIL and DIW, of family filial from those 15 parent pairs.DIL and DIW were regressed on the MOL, SIM, d2, H0and PIC. Results showed MOL of five SSR loci(12, 17, 24, 81 and 85) and SIM of five loci(17, 21, 24, 81and 85) all shared significant positive correlation with DIL(r=0.482, P=0.035 and r=0.479, P=0.035, respectively); H0of six SSR loci(11, 17, 21, 24, 26 and 85) had significant positive correlation with DIW(r=0.551, P=0.017); PIC of two SSR loci(9and 26) had significant positive(r=0.519, P=0.024) correlation with DIL, while that and of four loci(17, 24, 27 and 85) had significant negative correlation(r=-0.519,P=0.024), with DIL. This present study suggested that filial growth expression could be predicted by using molecular related indexes in turbot breeding practice, and the accuracy of prediction depends on more SSR loci, especially associated with QTL. 展开更多
关键词 TURBOT MICROSATELLITE Molecular related indexes Heterosis prediction
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Genetic analysis of morphological index and its related taxonomic traits for classification of indica 被引量:1
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《Chinese Rice Research Newsletter》 1999年第3期1-2,共2页
The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popu... The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popula-tion derived from anther culture of ZYQ8/JX17 F,a typical inter-subspecies hybrid,was used to investigate the six taxonomictraits,i.e.leaf hairiness(LH),color of hullwhen heading(CHH),hairiness of hull(HH),length of the first and second panicle internode(LPI),length/width of grain(L/W),andphenol reaction(PH).The morphological in- dex(MI)was also calculated.Based on themolecular linkage map constructed from this 展开更多
关键词 LPI MI Genetic analysis of morphological index and its related taxonomic traits for classification of indica length
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Science Citation Index Expanded Journal Lists related to neurosciences & neuroimaging
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《Neural Regeneration Research》 SCIE CAS CSCD 2011年第17期1346-1360,共15页
SCIENCE CITATION INDEX EXPANDED-NEUROSCIENCES-JOURNAL LIST Total journals: 245 1. ACS CHEMICAL NEUROSCIENCE Monthly ISSN: 1948-7193 AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, USA, DC, 20036 · Science Cita... SCIENCE CITATION INDEX EXPANDED-NEUROSCIENCES-JOURNAL LIST Total journals: 245 1. ACS CHEMICAL NEUROSCIENCE Monthly ISSN: 1948-7193 AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, USA, DC, 20036 · Science Citation Index Expanded · BIOSIS Previews 展开更多
关键词 BIOSIS NEUROIMAGING ISSN ACTA Science Citation index Expanded Journal Lists related to neurosciences
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Evaluating the Health Risks of Pneumonia from Airborne Bacterial Communities Using 16S rDNA Sequences of Pneumonia-related Pathogens 被引量:2
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作者 GUO Jian Guo KONG Qi +2 位作者 LIU Ce KANG Tai Sheng QIN Chuan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2021年第4期265-271,共7页
Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populat... Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populations,particularly for pneumonia.Methods We developed a method to evaluate risks from airborne microorganisms,guided by the principle that closer evolutionary relationships reflect similar biological characteristics,and thus used16 S rDNA sequences of 10 common pneumonia-related bacterial pathogens.We calculated a risk of breath-related(Rbr)index of airborne bacterial communities and verified effectiveness with artificial flora and a clinical project.Results We suggested applying Rbr80 to evaluate the health risks of airborne bacterial communities that comprise 80% of dominant operational taxonomic units(OTUs).The feasibility of Rbr80 was confirmed by artificial flora and by pneumonia data from a hospital.A high Rbr80 value indicated a high risk of pneumonia from airborne bacterial communities.Conclusion Rbr80 is an effective index to evaluate the pneumonia-associated risk from airborne bacteria.Values of Rbr80 greater than 15.40 are considered high risk. 展开更多
关键词 Airborne bacteria The risk of breath related index(Rbr) PNEUMONIA Health risk
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Comparison of different surrogate markers of muscle mass for the diagnosis of sarcopenia in patients with colorectal cancer
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作者 Jia-Le Li Qi Zhou +6 位作者 Qi-WenWang De-Cheng Luo Jiang-Hong Huang Xin-Long Yu Si-Zhi Liang Shuang-Yi Tang Jia-Liang Gan 《Journal of Nutritional Oncology》 2024年第1期25-36,共12页
Background:This study compared the validity of the creatinine-to-cystatin C ratio(CCR),sarcopenia index(SI),and relative skeletalmuscle index(RSMI)as predictors of sarcopenia in patients with colorectal cancer(CRC)and... Background:This study compared the validity of the creatinine-to-cystatin C ratio(CCR),sarcopenia index(SI),and relative skeletalmuscle index(RSMI)as predictors of sarcopenia in patients with colorectal cancer(CRC)and explored their impact on the patient prognosis.Methods:We retrospectively studied patients with CRC who underwent surgical intervention at the Department of Colorectal and Anal Surgery,situatedwithin the First Affiliated Hospital of GuangxiMedical University.The investigation spanned from January 2015 to December 2017,encompassing a cohort of patients subject to surgical management forCRC during this period.Pearson’s correlation analysis was employed to evaluate the relationships between the CCR,SI,RSMI,and skeletal muscle index(SMI)and the patient prognosis.Receiver operating characteristic(ROC)curves were generated to evaluate the predictive precision of these biomarkers and ascertain the optimal cutoff values.Multivariate logistic regression analysis was conducted to pinpoint the independent factors linked with sarcopenia.Survival analyses,contingent on different surrogate markers of muscle mass and sarcopenia,were performed utilizing the Kaplan-Meier method alongside the log-rank test.Results:Weenrolled 815 patientswithCRC(522 male and 293 female patients)whowere eligible for the analysis.In accordancewith the guidelines set forth by the International Consensus on Sarcopenia,sarcopenia was diagnosed in a collective total of 503 patients.A Pearson’s correlation coefficient(r)analysis demonstrated that the CCR,SI,and RSMI were positively correlated with the SMI.In both male and female patients,the RSMI(male:r=0.400,P<0.001;female:r=0.640,P<0.001)was more strongly correlated with the SMI than with the CCR(male:r=0.203,P<0.001;female:r=0.192,P<0.001)or SI(male:r=0.335,P<0.001;female:r=0.285,P<0.001).In male patients,the areas under the ROC curves(AUC)for the CCR,SI,and RSMI were 0.596[(95%confidence interval(CI)=0.545-0.647)],0.648(95%CI=0.599-0.698),and 0.681(95%CI=0.629-0.733),respectively.In female patients,the AUC for the CCR,SI,and RSMI were 0.615(95%CI=0.551-0.680),0.660(95%CI=0.598-0.722),and 0.772(95%CI=0.719-0.825),respectively.A multivariable logistic regression analysis demonstrated that the CCR remained an influential factor for sarcopenia after correcting for confounding[odds ratio(OR)=0.993,95%CI=0.986-1.000,P=0.038].The SI and RSMI also remained influential factors for sarcopenia after correcting for confounding factors(OR=0.983,95%CI=0.972-0.994,P=0.002;and OR=0.401,95%CI=0.320-0.502,P<0.001,respectively).The groups characterized by low CCR and SI demonstrated notably reduced overall survival compared with their counterparts with high CCR and SI(P=0.007 and P=0.001,respectively),whereas the RSMI and sarcopenia did not exhibit a significant correlation with survival(P=0.608 and P=0.062,respectively).Conclusions:The CCR,SI,and RSMI all have predictive value for sarcopenia in patients with CRC.TheRSMI was a better predictor of sarcopenia than either the CCR or SI in both male and female patientswith CRC.However,the RSMI did not have any significant value for predicting the prognosis of patients with CRC.Subsequent prospective investigations are warranted to elucidate a superiormarker or amalgamation thereof,capable of accurately prognosticating sarcopenia and the overall prognosis in individuals diagnosed with CRC.Such studies should aim to meticulously evaluate a comprehensive array of potential markers,considering their individual and collective predictive value in delineating the clinical trajectory of CRC patients.By conducting rigorous prospective analyses,researchers can strive to uncover novel insights into the complex interplay between sarcopenia and CRC outcomes,thereby facilitating the development of more precise prognostic models and tailored therapeutic approaches. 展开更多
关键词 Colorectal cancer Creatinine-to-cystatin C ratio Sarcopenia index Relative skeletal muscle index SARCOPENIA
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RELATIVE BRIGHTNESS INDEX AND IT'S CLIMATIC SIGNIFICANCE FROM LACUSTRINE SEDIM ENT OF NAPAHAI LAKE,NORTHWESTERN YUNNAN PLATEAU,CHINA 被引量:1
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作者 YINYong FANGNian-qiao 《Chinese Geographical Science》 SCIE CSCD 2002年第3期249-253,共5页
Information on the palaeoenvironm ent from Late Pleistocene to Holocen e in northwestern Yannan Plateau has been deduced from a study of a 28.81m-long core taken from Napahai Lake.The results from Relative Brightness ... Information on the palaeoenvironm ent from Late Pleistocene to Holocen e in northwestern Yannan Plateau has been deduced from a study of a 28.81m-long core taken from Napahai Lake.The results from Relative Brightness In-dex(RBI )as well as those from the lithological analyses of bulk sediments,total organic carbon and granulometric analy-ses have been used to reconstruct the environmental and climatic evoluti on of the area.The ages were provided by three 14 C datings.The record suggested a climate fluctuation between warm-dry a nd cool-wet from ca.57to 32ka B.P.,which led a shallowing and swamping of the l ake.The water level again increased quickly at ca.32ka B.P.,reached it’ s peak during LGM(Last Glacial Maximum,ca.18-20ka B.P.)and remained relative high until ca.15ka B.P.The high wa-ter level at LGM is attributed to cold-wet conditions.The area experienced an abrupt and unstable climatic ch anges dur-ing the transition period from15to 10ka B.P.with a dominated littoral en vironment.Awarm-dry climate led to the contrac-tion of the lake during the Holocene a nd reed-swamps became dominant.After a minor wet-cool pulse during the L ate Holocene,the modern climate became to be established. 展开更多
关键词 relative brightress index total organic carbon particle size PALAEOCLIMATE napahai lake
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The Existence of Solutions for a Class of Schr¨odinger Equations via Morse Index Theory
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作者 LI Jia-yang WANG Qi 《Chinese Quarterly Journal of Mathematics》 2022年第3期274-280,共7页
In this paper,with the relative Morse index,we will study the existence of solutions of(1.1)under the assumptions that V satisfies some weaker conditions than those in[2].
关键词 Relative Morse index Morse theory Schr¨odinger equations
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Analysis on Factors Causing Project Delays in Road and Highways Sector in India Using Relative Ranking Index Technique
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作者 Siddesh K.Pai Neeraj Anand Ankur Mittal 《Journal of Construction Research》 2021年第2期43-48,共6页
On-time completion of road infrastructure projects is a critical goal.When projects were not completed on schedule and real construction progress is slower than expected,the inconvenience and disruption to business ac... On-time completion of road infrastructure projects is a critical goal.When projects were not completed on schedule and real construction progress is slower than expected,the inconvenience and disruption to business access increases.On time completion is linked to economic and social welfare,as well as safety.Construction delays continue to be a typical occurrence,despite the need of prompt completion.A literature study is conducted in this context in order to learn more about the causes and factors that contribute to delays.Following a thorough review of the literature,it was determined that a questionnaire survey is the most effective and trustworthy way for gathering information about the causes and quantifying delays caused by emergent factors.The Relative Importance Index(RII)method was used to analyze the data,and the reasons for the delay were prioritized according to their importance.This study focuses on the emergent concerns/causes and reasons of concern in road infrastructure projects,as well as how to priorities these issues sequentially during the planning stage.This study survey can assist construction companies doing business in India in understanding the essential or sensitive issues that require special attention in order to conduct their businesses smoothly in this country while employing appropriate project management practices. 展开更多
关键词 Relative importance index Issues of concern Delay factors Road Construction projects
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Assessing the socio-cultural impact of urban revitalisation using Relative Positive Impact Index(RPII)
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作者 Shahim Abdurahiman A.K.Kasthurba Affa Nuzhat 《Built Heritage》 CSCD 2024年第1期67-83,共17页
Urban heritage is a vital resource that connects communities to their local identity.Unplanned developments and rapid urbanisation often harm the authenticity of historic areas,disrupting the cultural fabric and alter... Urban heritage is a vital resource that connects communities to their local identity.Unplanned developments and rapid urbanisation often harm the authenticity of historic areas,disrupting the cultural fabric and altering their character.This study introduces the Relative Positive Impact Index(RPll),a novel technique for assessing the socio-cultural impacts of urban revitalisation.The significance of RPII lies in its ability to quantitatively evaluate the impacts on the cultural fabric and integrity of historic urban areas,which is crucial for sustainable urban development.The study's objective is to apply RPII in evaluating qualitative socio-cultural characteristics in historic urban areas,with a focus on four main criteria and 16 sub-criteria,in the case of the Kuttichira precinct.The methodology integrates the analysis of published literature,a quantitative survey mapping the stakeholders'perception,and qualitative insights.This approach facilitates an in-depth understanding of how urban revitalisation affects local socio-cultural dynamics,preserving the authenticity and character of historic areas.The study reveals that the revitalisation project in Kuttichira positively impacts the socio-cultural fabric of the area,maintaining cultural integrity and addressing social challenges.These findings offer valuable insights for sustainable urban development and policymaking in historic areas.The study recommends the application of RPll in other urban precincts for comparative analysis and further development of urban development practices,contributing to informed urban policy and planning decisions. 展开更多
关键词 urban revitalisation socio-cultural impact relative positive impact index urban heritage sustainability
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不同采伐干扰方式对热带山地雨林谱系结构的影响 被引量:12
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作者 卜文圣 许涵 +3 位作者 臧润国 丁易 张俊艳 林明献 《林业科学》 EI CAS CSCD 北大核心 2014年第4期15-21,共7页
以海南岛热带山地雨林老龄林及经过择伐和皆伐后自然恢复约40年的次生林为研究对象,通过群落学调查和样地环境因子测定,分析不同干扰方式对群落组成及谱系结构的影响,探讨不同干扰方式下环境因素对群落谱系结构的影响。结果表明:历经40... 以海南岛热带山地雨林老龄林及经过择伐和皆伐后自然恢复约40年的次生林为研究对象,通过群落学调查和样地环境因子测定,分析不同干扰方式对群落组成及谱系结构的影响,探讨不同干扰方式下环境因素对群落谱系结构的影响。结果表明:历经40年的恢复,2种方式干扰后自然恢复次生林不同径级(1≤DBH<5 cm为幼树、5≤DBH<10 cm为小树、DBH≥10 cm为成年树)树种的丰富度已接近老龄林水平,其幼树、小树的多度显著高于老龄林,但其胸高断面积依旧显著低于老龄林;从老龄林、择伐后恢复的次生林到皆伐后恢复的次生林,群落幼树和总体的谱系结构由聚集转向发散,而成年树的谱系结构则恰好相反,小树的谱系结构基本上是随机的;在老龄林中,群落各个径级的谱系结构均随着海拔的升高由发散转向聚集;在择伐后恢复的次生林中,除成年树外,群落的谱系结构随土壤含水量的增加由聚集转向发散;在皆伐后恢复的次生林中,幼树的谱系结构随土壤有机质含量的增加由发散转向聚集,而小树和成年树的谱系结构则由聚集转向发散。 展开更多
关键词 群落组配 干扰体系 环境筛 采伐方式 净谱系亲缘关系指数 径级结构
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一种改进的异构链路协同预测算法研究 被引量:3
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作者 盛权为 汪一百 高阳 《计算机工程与应用》 CSCD 北大核心 2017年第15期155-163,共9页
现有的链路预测方法仅考虑单种链路类型预测或多种链路类型的独立预测,经常使得预测结果不够准确。为此,研究了异构信息网络中多种链路类型的协同预测问题。根据源节点的相似节点和目标节点的相似节点之间的当前链路信息,提出了同质连... 现有的链路预测方法仅考虑单种链路类型预测或多种链路类型的独立预测,经常使得预测结果不够准确。为此,研究了异构信息网络中多种链路类型的协同预测问题。根据源节点的相似节点和目标节点的相似节点之间的当前链路信息,提出了同质连接原理,设计了一种针对不同类型节点的相关性指标,用于描述不同类型节点间的链路存在概率,并将其与传统的邻近性指标相结合拓展到异构链路预测中。然后,将异构信息网络中的被标记数据和无标记数据融合起来,提出一种异构链路协同预测算法(Heterogeneous Collective Link Prediction,HCLP),通过获得不同类型链路间的各种复杂关系,结合互补性预测信息,实现多种链路类型的协同预测。基于真实场景的实验结果表明,所提的链路协同预测方法可有效提升异构信息网络的链路预测性能。 展开更多
关键词 异构信息网络 相关性指标 同质连接 链路存在概率 协同预测 邻近性指标
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基于不同尺度和模型的小秦岭谱系结构研究 被引量:1
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作者 牛帅 毕帅帅 +4 位作者 王雪颖 韩军旺 贾宏汝 叶永忠 袁志良 《河南农业大学学报》 CSCD 北大核心 2017年第4期495-502,共8页
为探索研究尺度、零模型与群落谱系结构的关系,在小秦岭自然保护区建立1 hm^2样地,运用约束型、非约束型零模型分别从10、20、25 m 3个研究尺度上分析群落谱系结构,结果表明:(1)非约束型模型下,谱系结构聚集;约束型模型下,10、20 m尺度... 为探索研究尺度、零模型与群落谱系结构的关系,在小秦岭自然保护区建立1 hm^2样地,运用约束型、非约束型零模型分别从10、20、25 m 3个研究尺度上分析群落谱系结构,结果表明:(1)非约束型模型下,谱系结构聚集;约束型模型下,10、20 m尺度上,谱系聚集,25 m尺度上谱系分散。对比发现,随研究尺度增大,谱系聚集程度降低,趋于分散,可能是由于环境异质性对物种分布的影响程度降低,密度制约作用增强所致。(2)空间因子对谱系结构的影响远远大于地形因子,随研究尺度增加,空间因子及地形因子的解释量逐渐增大。地形的不同营造了不同的空间差异,二者密切相关。因此,空间因子是影响谱系结构形成的直接因素,而地形因子是间接因素。 展开更多
关键词 谱系结构 地形因子 空间因子 净谱系亲缘关系指数 最近种间亲缘关系指数
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ENVIRONMENTAL RELATIVE BURDEN INDEX:A STREAMLINED LIFE CYCLE ASSESSMENT METHOD FOR FACILITIES POLLUTION PREVENTION
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作者 Deborah E.Dickerson 《Journal of Green Building》 2016年第1期95-107,共13页
This paper describes a new semi-quantitative streamlined life cycle assessment(SLCA)method,the Environmental Relative Burden Index(ERBI),for describing and ranking the relative environmental burdens associated with fa... This paper describes a new semi-quantitative streamlined life cycle assessment(SLCA)method,the Environmental Relative Burden Index(ERBI),for describing and ranking the relative environmental burdens associated with facility operations and maintenance options.The long-range goal is for this ERBI method to serve as a pollution-prevention decision support tool for facilities managers,when faced with competing operations and maintenance alternatives.The specific application pre-sented in this paper evaluates asbestos-containing materials(ACM)and lead-based paint(LBP)management options in public school facilities.The ERBI methodol-ogy is adapted from previous streamlined semi-quantitative LCA methodologies and is described in detail.The ERBI is then employed to evaluate the relative environmental impacts of six management strategies for these hazardous building materials:management in-situ,encapsulation/containment,and full abatement/disposal,for both ACM and LBP.SLCA goal definition,system boundaries,ERBI matrix,and overall ERBI Ratings(RERB)for each material management strategy are presented.The ERBI can be a useful tool in prioritizing building maintenance alternatives,especially in cases where detailed quantitative data are unavailable. 展开更多
关键词 Life Cycle Assessment buildings maintenance environmental hazards Environ-mental Relative Burden index(ERBI)
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A Study on the Multi-Compartment Linear Circulation Pharmacokinetic Model for the Targeting Drug Delivery System
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作者 张志荣 永井恒司 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第2期81-87,共7页
By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentratio... By analyzing the observed phenomena and the data collected in the study, a multi-compartment linear circulation model for targeting drug delivery system was developed and the function formulas of the drug concentration-time in blood and target organ by computing were figured out. The drug concentration-time curve for target organ can be plotted with reference to the data of drug concentration in blood according to the model. The pharmacokinetic parameters of the drug in target organ could also be obtained. The practicability of the model was further checked by the curves of drug concentration-time in blood and target organ(liver) of liver-targeting nanoparticles in animal tests. Based on the liver drug concentration-time curves calculated by the function formula of the drug in target organ, the pharmacokinetic behavior of the drug in target organ(liver) was analyzed by statistical moment, and its pharmacokinetic parameters in liver were obtained. It is suggested that the (relative targeting index( can be used for quantitative evaluation of the targeting drug delivery systems. 展开更多
关键词 Pharmacokinetic model for targeting drug delivery systems Multi-compartment linear circulation pharmacokinetic model Relative targeting index
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川西亚高山暗针叶林及其采伐次生林林下分层谱系结构 被引量:10
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作者 陈欢欢 许格希 +7 位作者 马凡强 刘顺 张淼淼 曹向文 陈健 赵广东 杨洪国 史作民 《林业科学》 EI CAS CSCD 北大核心 2020年第7期1-11,共11页
【目的】研究川西亚高山不同演替阶段森林群落的林下乔灌草层次谱系结构及对其驱动的生态学过程,为川西林区森林生物多样性保护与生态系统修复提供理论依据。【方法】利用川西亚高山原始暗针叶林(以下简称原始林)及其在1950—1969年和1... 【目的】研究川西亚高山不同演替阶段森林群落的林下乔灌草层次谱系结构及对其驱动的生态学过程,为川西林区森林生物多样性保护与生态系统修复提供理论依据。【方法】利用川西亚高山原始暗针叶林(以下简称原始林)及其在1950—1969年和1970—1989年采伐后形成的天然次生林(以下简称次生林)的林下(不包括主林层,因其树种组成相对单一)乔灌草群落生态学调查资料,基于APGⅢ谱系框架,构建不同演替阶段森林群落的乔灌草系统发育树,选用广泛使用的谱系多样性指数——净亲缘指数(NRI)和最近类群指数(NTI),量化和评估不同演替阶段林型的乔灌草分层谱系结构及对其驱动的生态学过程。【结果】原始林亚林层物种组成谱系离散(NRI<0;NTI<0),即共存物种亲缘相疏,而原始林其他层次(草本层、灌木层与小乔木层)物种组成倾向于谱系聚集(NRI>0;NTI>0),即共存物种亲缘相近;2个不同采伐年代形成的次生林的草本层和亚林层的谱系结构呈现出林型间相似但层次间相反的模式(草本层:谱系离散;亚林层:谱系聚集),灌木层和小乔木层则表现为层间相似但林型间相反的模式(1950—1969年:谱系聚集;1970—1989年代:谱系离散);不同演替阶段森林群落的林下乔灌草NRI与NTI均极显著正相关(0.698≤R2≤0.769,P<0.001);不同演替阶段森林群落的林下乔灌草分层谱系结构(NRI与NTI)与物种多样性(香侬多样性指数H′)的关联分析绝大部分未通过显著性检验,但林下乔灌草谱系结构与H′的局部多项式回归分析发现,原始林和1970—1989年采伐后次生林中的H′与NRI、H′与NTI的相关变化趋势表现出相似的波峰-波谷变化模式。【结论】川西亚高山原始暗针叶林及其采伐次生林的林下乔灌草层次谱系结构在层次间和林型间存在差异性。环境过滤是驱动原始林中草本层、灌木层和小乔木层物种谱系组成的主要生态学过程,竞争互斥则塑造亚林层中的物种谱系组成。次生林的林下乔灌草层次谱系结构及对其驱动的生态学过程大致与原始林相反,表现为环境过滤主导亚林层的谱系结构,竞争互斥主导草本层的谱系结构。川西亚高山不同演替阶段森林群落的林下乔灌草层次谱系多样性与物种多样性相互独立。 展开更多
关键词 净亲缘指数与最近类群指数 生态位理论 乔灌草层次 谱系结构 暗针叶林
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常绿阔叶林谱系多样性对幼苗存活率的影响 被引量:8
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作者 陈英 《植物生态学报》 CAS CSCD 北大核心 2009年第6期1084-1089,共6页
密度制约机制对于维护生物多样性有非常重要的作用。随着对密度制约机制的深入研究,人们逐渐认识到:不仅在种内存在密度制约效应,亲缘关系相近的物种之间也可能表现出密度制约效应。Webb在2000年提出的NRI(净种间亲缘关系指数)、NTI(净... 密度制约机制对于维护生物多样性有非常重要的作用。随着对密度制约机制的深入研究,人们逐渐认识到:不仅在种内存在密度制约效应,亲缘关系相近的物种之间也可能表现出密度制约效应。Webb在2000年提出的NRI(净种间亲缘关系指数)、NTI(净最近种间亲缘关系指数)考虑了比较全面的谱系信息,获得了广泛的应用。该文采用NRI、NTI来代表种间关系,并用Logistic回归模型来分析了谱系因子对浙江省开化县古田山自然保护区24hm2永久监测样地中501个幼苗样方死亡率的影响。通过对6次幼苗调查数据的分析表明:不仅相同物种密度对于幼苗的死亡率有显著影响,当密度达到一定水平时,谱系因子同样也对幼苗的死亡率有显著影响——苗区中个体间的亲缘关系越近,幼苗个体的死亡率越高。 展开更多
关键词 密度制约 谱系多样性 净种间亲缘关系指数 LOGISTIC回归 幼苗死亡率
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Combining Ability and Genetic Effects of Germination Traits of Brassica napus L.Under Waterlogging Stress Condition 被引量:5
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作者 CHENG Yong GU Min +3 位作者 CONG Ye ZOU Chong-shun ZHANG Xue-kun WANG Han-zhong 《Agricultural Sciences in China》 CAS CSCD 2010年第7期951-957,共7页
Cross combinations from six rapeseed cultivars and lines were evaluated under waterlogging stress condition in order to understand the genetic mechanism of waterlogging tolerance of Brassica napus L.and provide reason... Cross combinations from six rapeseed cultivars and lines were evaluated under waterlogging stress condition in order to understand the genetic mechanism of waterlogging tolerance of Brassica napus L.and provide reasonable improvement programs.There were six germination traits investigated on combining ability and heritability using complete diallel crossing method designed for 30 combinations from those six cultivars and lines.The traits included relative root length,stem length,fresh weight per plant,survival rate,electrical conductivity,and vigor index.After flooding treatment,the six traits of parents and F1 were analyzed.The general combining ability(GCA) and special combining ability(SCA) of germination traits were analyzed using Griffing I method.Among 30 cross combinations,the GCA was significantly different among six waterlogging resistance traits.The SCA of these traits was significantly different except the SCA of electrical conductivity.As a representative trait of waterlogging tolerance in rapeseed,relative vigor index had the highest narrow heritability and relatively low broad heritability.The cultivars Zhongshuang 9 and P79 had higher tolerance potential to waterlogging stress.It can be concluded that combining ability and genetic effects of relative vigor index during germination stage could be used to identify the waterlogging tolerance of rapeseed in breeding program. 展开更多
关键词 Brassica napus L. relative vigor index waterlogging tolerance germination trait combining ability diallel crossing
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Relative active tectonics evaluation using geomorphic and drainage indices, in Dadra and Nagar Haveli, western India 被引量:4
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作者 Naveen Kumar Rakesh K.Dumka +1 位作者 Kapil Mohan Sumer Chopra 《Geodesy and Geodynamics》 CSCD 2022年第3期219-229,共11页
The present study area,Dadra and Nagar Haveli,contains several lineaments and traces of active faults.The various aspect of the geomo rphic analysis,i.e.,stream length(SL) gradient,hypsometric integral(HI),basin shape... The present study area,Dadra and Nagar Haveli,contains several lineaments and traces of active faults.The various aspect of the geomo rphic analysis,i.e.,stream length(SL) gradient,hypsometric integral(HI),basin shape(BS),valley floor(VF),have been applied to evaluate the relative index of active tectonics(RIAT) of the Damanganga watershed.The high and low zones of tectonic activity have been identified based on the geomorphic analysis of the watershed.After evaluation of all indices,three classes,class IIhigh(1.3 ≤RIAT <1.5),class Ⅲ-moderate(1.5 ≤RIAT <1.8),and class Ⅳ-low(1.8 ≤RIAT),have been obtained to outline the degree/gradation of comparative tectonic activities in the study area.The appraised outcome of the RIAT dispersal is also well reinforced by the geomorphic evidence in the field.The collective outcomes of geomorphic evidence,such as stream deflection and analysis of lineament,deflection of streams,and geomorphic indices,conceal that the Damanganga watershed is affected by tectonic activity. 展开更多
关键词 Active tectonics Geomorphic indices Relative index of active tectonics(RIAT) Drainage indices
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Phylogenetic patterns of shrub communities along the longitudinal and latitudinal gradients on the northeastern Qinghai–Tibetan Plateau 被引量:1
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作者 XIAO Yuan-ming YANG Lu-cun +3 位作者 NIE Xiu-qing LI Chang-bin XIONG Feng ZHOU Guo-ying 《Journal of Mountain Science》 SCIE CSCD 2020年第5期1106-1114,共9页
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 mo... 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. 展开更多
关键词 Phylogenetic diversity Phylogenetic community structure Shrub communities Qinghai–Tibetan Plateau Net relatedness index Nearest Taxon index
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Influence of form and quantity of chromium on the development and survival of two silkworm(Bombyx mori L.)races 被引量:1
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作者 FrederickB.Tucker WANGKai-xiong +1 位作者 LUShun-lin XULi-jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第6期744-748,共5页
Growth inhibitory activity has proven important in Qiufeng×Baiyu and Qingsong×Haoyue silkworm larvae. The consumption of mulberry leaves was reduced in both silkworm races while Qiufeng×Baiyu larvae s... Growth inhibitory activity has proven important in Qiufeng×Baiyu and Qingsong×Haoyue silkworm larvae. The consumption of mulberry leaves was reduced in both silkworm races while Qiufeng×Baiyu larvae showed the higher reduction in leaf consumption. From the results obtained, it was revealed that even at low concentrations of 400 mg/L of either Cr(Ⅲ) or Cr(Ⅵ) ions, growth of Qiufeng × Baiyu and Qingsong × Haoyue was significantly depressed. Depression in relative growth index(RGI) and high death rate in both silkworm races indicated that the different concentrations of the two ions used caused their growth inhibitions. Through linear regression analysis, the EC 50 (concentration of the compound that caused 50% reduction) was interpolated for both tested compounds. EC 50 (mg/L) of Cr (Ⅲ) ions in Qiufeng × Baiyu and Qingsong × Haoyue were 800 and 600 respectively. EC 50 (mg/L) of Cr(Ⅵ) ions in Qiufeng × Baiyu and Qingsong × Haoyue was 600 and 316 respectively. According to the analysis of relative growth index, and an analysis of linear regression technique for measuring the growth of the silkworm races, it was indicated that the form of Cr affected growth rates, growth inhibition responses of the larvae, and toxicological effects. Thus, form and quantity of Cr accumulating in silkworms reared with contaminated leaves are likely to influence their population dynamics. 展开更多
关键词 CHROMIUM relative growth index antifeedant activity BIOASSAY
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