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Mate-choice copying： Status quo and where to go

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Current Zoology 2015年第6期61卷 1073-1081页

作者： Klaudia WITTE nina KNIEL Ilka Maria KURECK Research Group of Ecology and Behavioral Biology Institute of Biology University of Siegen 57068 Siegen Germany

Mate-choice copying is a fascinating and widespread mate-choice strategy. Individuals gather public information about potential mates by observing others during sexual interactions and choose or reject the same individual as a mate as the observed individual did before. The influence of copying behavior on an individual＇s mate choice can be so strong that socially acquired information can override genetically based preferences for certain phenotypes. Thus, mate-choice copying enforces dy- namic processes in sexual selection. Here, we review the current state of research on mate-choice copying and focus on sex-specific aspects. We present evidence that mate-choice copying can support the evolution of novel sexual ornaments, and we discuss potential costs of mate-choice copying when public information is not reliable. Moreover, we discuss the conflict faced by males that copy since mate-choice copying increases sperm competition. In conclusion we suggest interesting topics for future research in mate-choice copying .

关键词： Mate-choice copying Public information Audience effect Sperm competition Novel ornaments

Host preference of the major strains of Plum pox virus--Opinions based on regional and world-wide sequence data

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Journal of Integrative Agriculture 2017年第3期16卷 510-515页

作者： nina Sihelská Miroslav Glasa Zdeno W Subr Biomedical Research Center Institute of Virology Slovak Academy of Sciences Bratislava 84505 Slovak Republic

Plum pox virus（PPV）causes sharka-the most serious viral disease of stone fruit *** is wide spread in Europe and Mediterranean Basin,its incidence has been further approved in Asia and both *** PPV strains have been recognized until now（PPV-D,PPV-M,PPV-Rec,PPV-EA,PPV-C,PPV-T,PPV-W,PPV-CR,and PPV-An）,forming molecularly distinct entities,however,only partially differentiable by their biological or epidemiological *** most strict virus-host linkages under natural conditions have been detected for strains naturally infecting cherries（PPV-C and PPV-CR）.However,although less stringent but still clear host preference is observed also for three epidemiologically most important strains（PPV-D/plum/apricot,PPV-M/peach,and PPV-Rec/plum）.So far no genetic marker has been mapped in the PPV genome,which responsibility for the host specificity/preference could be explicitly *** this review,we focus on the host preference of three major PPV strains as evidenced by analysis of an extensive dataset of PPV isolates of Slovak and world-wide ***,we discuss several performed relevant experiments and further possible research procedures aimed to better understand the genetic determinants and mechanisms of the host preference of this potyvirus.

关键词： sharka Prunus virus-host interactions

An Integrated Causal Path Identification Method

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Wuhan University Journal of Natural Sciences 2019年第4期24卷 305-313页

作者： fEI nina YANG Youlong School of Mathematics and Statistics Xidian University

finding causality merely from observed data is a fundamental problem in science. The most basic form of this causal problem is to determine whether X leads to Y or Y leads to X in the case of joint observation of two variables X, Y. In statistics, path analysis is used to describe the direct dependence between a set of variables. But in fact, we usually do not know the causal order between variables. However, ignoring the direction of the causal path will prevent researchers from analyzing or using causal models. In this study, we propose a method for estimating causality based on observed data. first, observed variables are cleaned and valid variables are retained. Then, a direct linear non-Gaussian acyclic graph models(DirectLiNGAM) estimates the causal order K between variables. The third step is to estimate the adjacency matrix B of the causal relationship based on K. Next, since B is not convenient for model interpretation, we use adaptive lasso to prune the causal path and variables. further, a causal path graph and a recursive model are established. finally, we test and debug the recursive model, obtain a causal model with good fit, and estimate the direct, indirect and total effects between causal variables. This paper overcomes the randomness assigning causal order to variables. This study is different from the researcher’s understanding of his own model by generating some form of simulation data. The simplest and relatively unsmooth statistical learning method used in this study has obvious advantages in the field of interpretable machine learning.

关键词： observed variable path analysis causal order Direct LiNGAM causal path graph causal effect

A Modified T-test feature Selection Method and Its Application on the HapMap Genotype Data

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Genomics, Proteomics & Bioinformatics 2007年第3期5卷 242-249页

作者： nina Zhou Lipo Wang School of Electrical and Electronic Engineering Nanyang Technological University Singapore

Single nucleotide polymorphisms （SNPs） are genetic variations that determine the differences between any two unrelated individuals. Various population groups can be distinguished from each other using SNPs. for instance, the HapMap dataset has four population groups with about ten million SNPs. for more insights on human evolution, ethnic variation, and population assignment, we propose to find out which SNPs are significant in determining the population groups and then to classify different populations using these relevant SNPs as input features. In this study, we developed a modified t-test ranking measure and applied it to the HapMap genotype data. firstly, we rank all SNPs in comparison with other feature importance measures including f-statistics and the informativeness for assignment. Secondly, we select different numbers of the most highly ranked SNPs as the input to a classifier, such as the support vector machine, so as to find the best feature subset corresponding to the best classification accuracy. Experimental results showed that the proposed method is very effective in finding SNPs that are significant in determining the population groups, with reduced computational burden and better classification accuracy.

关键词： SNP modified t-test f-statistics SVM

females choose gentle, but not healthy or macho males in Campbell dwarf hamsters （Phodopus campbelli Thomas 1905）

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Current Zoology 2017年第5期63卷 545-554页

作者： Konstantin A. ROGOVIN Anastasiya M. KHRUSHCHOVA Olga N. SHEKAROVA nina A. VASlLIEVA nina Yu VASILIEVA A.N. Severtsov Institute of Ecology and EvoLution RAS Leninskii prospect 33 Moscow 119071 Russia

Androgen-dependent male sexual traits （STs） as well as immunocompetence are theoreticallyassumed to be key indicators of a male＇s quality for the mate-choosing female. We studied matechoice by sexually motivated （SM） females of Campbell＇s dwarf hamsters. females chose between2 tethered male siblings that differed in expression of STs. Males were unrelated to the female andable to contact and copulate with her. In both males, we measured sex-related morphology ofbody mass, mid-ventral specific skin gland, ano-genital distance, and external testicular *** also estimated levels of blood testosterone and cortisol, specific T- and B-cell immune re-sponses to antigens, as well as aggressive and sexual dominance in sibling males through add-itional encounter experiments with another SM female （male sibs could freely compete for thefemale）. We found that SM females chose a partner among 2 male sibs and spent over 80% of theirtime on average with the preferred male compared with the non-preferred one. Her choice was notassociated with the first visit of the chosen male, with a higher expression of sex-related traits,higher levels of blood testosterone, or with aggressive dominance. The choice was not associatedwith the intensity of T-cell immune response to phitohemagglutinin （PHA）. Instead there was a ten-dency for a negative relationship with the expression of STs and B-cell response to the antigenchallenge. The only character that unambiguously influenced female choice was the non-aggressive male to female grooming during sexual contact. There was no difference in breedingsuccess between preferred and non-preferred males paired with virgin females.

关键词： Campbell's dwarf hamsters, female mate choice, immunocompetence handicap, male-male aggression, sexual traits,testosterone.

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一种新型重度铬污染土壤修复技术

科技创新与应用 2024年第13期14卷 30-34页

作者：蒋妮娜李东李林高然重庆远达烟气治理特许经营有限公司科技分公司重庆401122 重庆大学环境与生态学院重庆400044

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原... 详细信息

我国退役铬化工企业的土壤铬污染严重,部分土壤六价铬浓度可高达10^(3)~10^(4)mg·kg^(-1),对植物生长、人类活动产生了不良影响。常用的铬污染土壤修复方法有还原修复技术、生物修复技术、酸淋洗-还原联合修复技术,用稀酸溶液加上还原剂将土壤中的六价铬浸出、还原。但酸溶液对难提取六价铬的溶解效果有限,且易引起土壤侵蚀等次生环境问题。碱性条件下重度铬污染土壤淋洗和还原的修复工艺能有效解决酸淋洗存在的土壤溶蚀、钙流失、含盐量大幅增加以及其他重金属浸出浓度超标等次生环境问题,且该技术通过碱淋洗还原工艺显著提高难提取六价铬的提取和还原效率,该研究形成经济可行、易于推广的铬污染土壤修复技术路线。

关键词：污染土壤修复重度铬六价铬

Item-level forecasting for E-commerce Demand with High-dimensional Data Using a Two-stage feature Selection Algorithm

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Journal of Systems Science and Systems Engineering 2022年第2期31卷 247-264页

作者： Hongyan Dai Qin Xiao nina Yan Xun Xu Tingting Tong Business School Central University of Finance and EconomicsBeijing 100081China Department of Management Operationsand MarketingCollege of Business AdministrationCalifornia State UniversityStanislausTurlockCA95382United States Institute of Supply Chain Analytics&International Business College Dongbei University of Finance and EconomicsDalian 116025China

With the rapid development of information technology and fast growth of Internet users,e-commerce nowadays is facing complex business environment and accumulating large-volume and highdimensional *** brings two challenges for demand ***,e-merchants need to find appropriate approaches to leverage the large amount of data and extract forecast features to capture various factors affecting the ***,they need to efficiently identify the most important features to improve the forecast accuracy and better understand the key drivers for demand *** solve these challenges,this study conducts a multi-dimensional feature engineering by constructing five feature categories including historical demand,price,page view,reviews,and competition for e-commerce demand forecasting on *** then propose a two-stage random forest-based feature selection algorithm to effectively identify the important features from the high-dimensional feature set and avoid *** test our proposed algorithm with a large-scale dataset from the largest e-commerce platform in *** numerical results from 21,111 items and 109 million sales observations show that our proposed random forest-based forecasting framework with a two-stage feature selection algorithm delivers 11.58%,5.81%and 3.68%forecast accuracy improvement,compared with the Autoregressive Integrated Moving Average(ARIMA),Random forecast,and Random forecast with one-stage feature selection approach,respectively,which are widely used in literature and *** study provides a useful tool for the practitioners to forecast demands and sheds lights on the B2C e-commerce operations management.

关键词： forecasting e-commerce high-dimensional feature feature selection

裂褶菌发酵西洋参工艺优化及体外抗氧化能力研究

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食品工业科技 2024年第7期45卷 142-151页

作者：王崑仑管立军高扬严松李家磊季妮娜李波周野黑龙江省农业科学院食品加工研究所黑龙江哈尔滨150086 黑龙江省食品加工重点实验室黑龙江哈尔滨150086 黑龙江省农业科学院大豆研究所黑龙江哈尔滨150086

为提高西洋参的经济价值,本研究以西洋参为原料,利用裂褶菌固态发酵西洋参,提高西洋参中活性成分的含量,并对发酵工艺进行优化。本研究以西洋参中总人参皂苷含量为指标,先从3种裂褶菌菌株中筛选出2号菌株作为固态发酵西洋参用菌。再对... 详细信息

为提高西洋参的经济价值,本研究以西洋参为原料,利用裂褶菌固态发酵西洋参,提高西洋参中活性成分的含量,并对发酵工艺进行优化。本研究以西洋参中总人参皂苷含量为指标,先从3种裂褶菌菌株中筛选出2号菌株作为固态发酵西洋参用菌。再对影响裂褶菌西洋参发酵物的总人参皂苷含量的4个因素(发酵温度、裂褶菌接种量、pH和发酵时间)进行单因素实验。在此结果基础上,利用响应面Box-Behnken试验设计进一步优化裂褶菌固态发酵西洋参工艺,确定优化后的工艺条件为:裂褶菌接种量10.90%,发酵温度31℃、发酵时间10 d,发酵pH5.9。在上述条件下,裂褶菌西洋参发酵物的总人参皂苷含量为10.28%,粗多糖含量为12.85%,总黄酮含量为0.67%,均比未发酵西洋参的高。并且大分子人参皂苷Rb1、Rg_(2)和Re含量降低,小分子人参皂苷Rg_(1)、Rc、Rb_(2)、>、Rd、Rg3、s-Rh_(2)、r-Rh_(2)和拟人参皂苷CK含量升高。其中,稀有人参皂苷Rg_(3)、s-Rh_(2)、r-Rh_(2)和拟人参皂苷CK为新出现皂苷。体外抗氧化实验表明裂褶菌西洋参发酵物的DPPH和ABTS^(+)自由基清除能力的IC_(50)值分别为31365和10910μg/mL,均强于未发酵西洋参。本研究证明了裂褶菌固态发酵西洋参提高了总人参皂苷、粗多糖、总黄酮和稀有人参皂苷的含量,增强了抗氧化能力,为西洋参的开发利用提供数据支持。

关键词：西洋参裂褶菌固态发酵响应面人参皂苷抗氧化

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关于新时代弘扬科学精神工作的几点思考

今日科苑 2024年第4期 78-85页

作者：董亚峥张亦旒鲍妮娜中国科协科学技术传播中心北京100012

新时代在解决科技支撑发展、公民科学素质进一步提升等问题时,弘扬科学精神都是重要的内容。文章分析了关于科学精神的理论研究和社会实践面临的挑战,从科学精神的概念体系入手,分析了新时代弘扬科学精神的关注重点,并对具体工作提出建... 详细信息

新时代在解决科技支撑发展、公民科学素质进一步提升等问题时,弘扬科学精神都是重要的内容。文章分析了关于科学精神的理论研究和社会实践面临的挑战,从科学精神的概念体系入手,分析了新时代弘扬科学精神的关注重点,并对具体工作提出建议,包括弘扬科学家精神、一流学术传统构建、人类命运共同体构建、文化自信等内容。

关键词：科学精神科学家精神一流学术传统人类命运共同体文化自信