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Sex differences in cognition and their relationship to male mate choice

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Current Zoology 2019年第3期65卷 285-293页

作者： Jason KEAGY Ross MINTER Robin M.TINGHITEELLA Department of Animal Biology School of Integrative Biology University of Illinois at Urbana-Champaign Urbana IL USA Linda Crnic Institute for Down Syndrome University of Colorado School of Medicine Aurora CO USA Department of Biological Sciences University of DenverDenverCOUSA

Male cognition has gained recognition as an important potential player in sexual selection. A number of studies have found positive correlations between male sexual signals and cognitive performance an d/or female pref ere nces for males with better cog nitive performance, although other studies have not fou nd these relati on ships. Sex roles can differ dramatically, and sex differen ces in selection on cog nition likely follow from the different tasks associated with these sex roles. Here, using threespine stickleback Gasterosteus aculeatus, a species with clearly diverge nt sex roles and mutual mate choice, we focus on the cognitive trait inhibitory control because males must differentially respond to reproductive females versus other sticklebacks while defending territories and refrain from eating eggs and fry while performing paternal care. We presented fish with a detour task four times over a period of 7 days, allowing us to assess initial inhibitory control and improvement over time. We ask 1) whether there are sex differences in inhibitory control and 2) whether male mate choice is associated with female inhibitory control. Although males outperformed females on three different measures of detour task performance across four trials, these differences were largely explained by males being less neophobic than females. Females took more trials to successfully solve the detour task, even after accounting for sex differences in neophobia. Female cognitive abilities, however, were unrelated to the vigor with which males courted them. The equivocal results regarding sex differences in cognitive ability suggest further study given the very different selection pressures each sex experiences.

关键词： cognition detour task mutual mate choice sexual selection threespine stickleback

Potato farmers’ preference for agricultural insurance in China: An investigation using the choice experimental method

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Journal of Integrative Agriculture 2020年第4期19卷 1137-1148页

作者： HUANG Ze-ying Alec ZUO SUN Jun-mao GUO Yan-zhi Institute of Food and Nutrition Development Ministry of Agriculture and Rural AffairsBeijing 100081P.R.China Centre for Global Food and Resources University of AdelaideAdelaide 5005Australia

Potato insurance plays an important role in transferring agricultural risks to promote the potato staple strategy. Understanding farmers’ real preferences for potato insurance attributes is important to improve the potato insurance. In this study, a choice experiment was designed with attributes such as peril, minimum compensation ratio for production loss, types of crops covered by insurance, annual premium per mu after subsidy, and complexity of claims procedures. We constructed a mixed logit model based on a questionnaire survey of 362 potato farmers’ choices of insurance attributes from 24 villages in Dingxi City of Gansu Province using random sampling. The results show that:(1) farmers prefer agricultural insurance with widely perils including output price drop and input cost risk;(2) farmers who have suffered plant disease and insect and pest damage are willing to pay a high premium for the insurance with a high compensation ratio and several types of crops covered;full-time farmers and large-scale farmers preferred insurance products with low complexity of claims procedures. Therefore, new potato insurance design could be considered specifically for different farmer groups such as those who had previous disaster experiences, and large-or small-scale farm operations.

关键词： agricultural insurance choice experimental method potato attributes preferences

Wrap choice during fundoplication

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World Journal of Gastroenterology 2019年第48期25卷 6876-6879页

作者： Simon R Bramhall Moustafa M Mourad Department of Surgery The County HospitalHereford HR12ERUnited Kingdom Department of Surgery Worcester Royal InfirmaryWorcester WR51DDUnited Kingdom

Gastro-oesphageal reflux disease is an increasing health burden.The mainstay of treatment has conventionally been medical therapy but since the introduction of laparoscopic surgery laparoscopic anti-reflux surgery has been increasingly used for intractable symptoms or in patients unwilling to take long term medication.The Nissen 360 degree wrap has traditionally been considered the gold standard operation but can be associated with significant complications.These complications include“gas bloat”and dysphagia and can occur relatively frequently.Various modifications have been described to the original operation and some of these have been described.In addition alternative wraps have been described which seem to have a reduced incidence of complications associated with their use.This editorial discusses the various types of wrap that can be performed and the minimum requirements of the surgical technique.The evidence from a recent meta-analysis of the randomised data has suggested that an anterior wrap is associated with a lower rate of complications and gives just as good control of reflux symptoms.The advantages and disadvantages of an anterior wrap are discussed.The lack of long term follow up data concerns some practitioners and at the moment the choice of wrap carried out still rests with the individual surgeon.

关键词： Fundoplication Wrap Laparoscopic Reflux disease choice

Key Factors Affecting Farmers’ choice of Corn Reduction under the China’s New Agriculture Policy in the ‘Liandaowan’ Areas, Northeast China

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Chinese Geographical Science 2019年第6期29卷 1039-1051页

作者： LIU Shiwei ZHANG Pingyu LIU Wenxin HE Xiuli Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China School of Geographical Sciences Southwest UniversityChongqing 400715China

Farmers are the main land managers, and their production decisions crucially affect crop outputs and farmland preservation.Understanding the motivations and factors underlying farmers’ decision making is a fundamental to implementation polices of government.This study analyzed factors that influence farmers’ choice of corn reduction under the China’s new agriculture policy in the ‘Liandaowan’ areas of Northeast China.This study collected data from 106 randomly selected households in 34 villages in ‘Liandaowan’ areas of Northeast China using a semi-structured questionnaire.Results showed that the Chinese corn structural adjustment plan confronted with many constraints, and most of farmers insist on planting corn.Drought and low accumulated temperature, no suitable substitution crop, farmers’ preferences, farmers’ education and age, relatively high comparative benefit of corn, the availability of machinery and technical assistance, subsidies and low family incomes all influence farmers’ choice of corn substitution.Based on our experimental results, we derived important policy implications for promoting corn structural adjustment incorporate increase crop diversity, promote soybean and corn rotation, provide adequate agricultural extension services, and increase the corn substitution subsidies and improve farmers’ income.

关键词： agriculture policy crop choice decision making impacts Northeast China

Demonstrating mate choice copying in spiders requires further research

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Current Zoology 2020年第2期66卷 215-216页

作者： R.Tucker GILMAN Kasey FOWLER-FINN Eileen A.HEBETS School of Earth and Environmental Sciences The University of ManchesterManchesterUK Department of Biology Saint Louis UniversitySt.LouisUSA School of Biological Sciences University of Nebraska-LincolnLincolnNEUSA

Mate choice copying-when individuals learn to prefer mates or mate types that have been chosen by others-can influence trait evo-lution and speciation(Varela et al.2018;Dion et al.2019).Most examples of mate choice copying are from fish,birds,and mammals including humans(Varela et al.2018).However,2 invertebrate examples-fruit flies and wolf spiders-have been used to argue that the phenomenon may be phylogenetically widespread,and perhaps the rule rather than the exception in nature(Varela et al.2018).Here,we revisit the evidence for mate choice copying in wolf spiders(Fowler-Fimn et al.2015)in light of new data(Gilman et al.2018).Then,we discuss why mate choice copying is a phenomenon that is likely to occur in wolf spiders,and why this deserves attention.

关键词： invertebrates mate choice copying Schizocosa sexual selection speciation spiders

Reproductive health and rights in the COVID-19 era:Why and how are rights and choices still the answer?

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Asian pacific Journal of Reproduction 2022年第4期11卷 155-157页

作者： Md Anwer Hossain Department of Population Sciences Faculty of Social SciencesUniversity of DhakaDhaka-1000Bangladesh

Amidst the coronavirus disease 2019(COVID-19)pandemic,the concern over the potential‘baby boom’or‘baby bust’had drawn renewed attention across the globe[1-3].However,historically alarmism over fertility rates gave rise to restrictive and coercive policies with an aim of‘controlling the population’that violated people’s sexual and reproductive health and rights(SRHR).In this perspective,the author argued that whether countries of the world face a COVID-19-induced short-term baby boom or bust,the solution lies in prioritizing the rights and choices of all people,especially their SRHR;not in adopting target-oriented population policies or coercive family planning programs.

关键词： priori fertility choice

choice of Species in China's Plantation Forestry

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北京林业大学学报 1992年第S2期14卷 15-24页

作者： Shen GuofangForest Resources College, Beijing Forestry University

This paper reviews the new developments in the choice of tree species for China’s plantation forestry in relation to forest regionalization and site classification. After a brief discussion on the fundamental principles of choosing species,it gives the statistical data of the species composition of established forest plantations and recommendation for suitable tree species for plantations in some important forestry regions. Results of studies in 3 different cases have been given to illustrate the research approach in choice of tree species in accordance with the planting sites.

关键词： choice of species forest regionalization site classification

Structural choice based on knowledge discovery system

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Journal of Harbin Institute of Technology(New Series) 2002年第3期9卷 263-266页

作者： XING Fangliang(邢方亮) WANG Guangyuan(王光远) College of Civil Engineering Harbin Institute of Technology Harbin 150090 China College of Civil Engineering Harbin Institute of Technology Harbin 150090 China

Structural choice is a significant decision having an important influence on structural function, social economics, structural reliability and construction cost. A Case Based Reasoning system with its retrieval part constructed with a KDD subsystem, is put forward to make a decision for a large scale engineering project. A typical CBR system consists of four parts: case representation, case retriever, evaluation, and adaptation. A case library is a set of parameterized excellent and successful structures. For a structural choice, the key point is that the system must be able to detect the pattern classes hidden in the case library and classify the input parameters into classes properly. That is done by using the KDD Data Mining algorithm based on Self Organizing Feature Maps (SOFM), which makes the whole system more adaptive, self organizing, self learning and open.

关键词： knowledge discovery in database data mining self-organizing feature maps structural choice

Coordination Costs, Market Size, and the choice of Technology

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2019年第1期14卷 131-148页

作者： Haiwen Zhou Department of Economics Old Dominion University Norfolk VA 23529 USA

Impact of coordination costs and market size on a firm's choice of technology is studied in a general equilibrium model in which finns engage in oligopolistic competition. A firm establishes an organizational hierarchy to coordinate its production. First, it is shown that an increase in market size leads a firm to choose a more specialized technology. Second, surprisingly, a robust result is that an increase in the level of coordination efficiency leads a firm to choose a less specialized technology.

关键词： division of labor coordination efficiency technology choice hierarchy market size