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Journal of Integrative Agriculture 2015年第11期14卷 2203-2217页

作者： kevin Chen WANG Xin-xin SONG Hai-ying Beijing Office International Food Policy Research Institute School of Economics and International Trade Zhejiang University of Finance and Economics International Business Administration College Zhejiang International Studies University

Food safety has received a great deal of attention in both developed and developing countries in recent years. In China, the numerous food scandals and scares that have struck over the past decade have spurred significant food safety regulatory reform, which has been increasingly oriented towards the public-private partnership model adopted by the Europe Union＇s （EU） food safety regulatory system. This paper analyzes the development of both the EU＇s and China＇s food safety regu- latory systems, identifies the current challenges for China and additionally considers the role of public-private partnership. The success of co-regulation in the food regulatory system would bring significant benefits and opportunities for China. Finally, this paper recommends additional measures like training and grants to improve the private＇s sector effectiveness in co-regulating China＇s food safety issues.

关键词： food safety co-regulation public-private partnership Food Safety Law of China European Union China

Computer-animated stimuli to measure motionsensitivity： constraints on signal design in theJacky dragon

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Current Zoology 2017年第1期63卷 75-84页

作者： kevin L. Woo Guillaume RIEUCAU Darren BURKE SUNY Empire State College Metropolitan Center 325 Hudson Street New York NY 10013-1005 USA Department of Biological Sciences Florida International University 3000 Northeast 151 St North Miami FL 33181 USA School of Psychology University of Newcastle 10 Chittaway Road Ourimbah New South Wales 2258Australia

Identifying perceptual thresholds is critical for understanding the mechanisms that underlie signalevolution. Using computer-animated stimuli, we examined visual speed sensitivity in the Jackydragon Amphibolurus muricatus, a species that makes extensive use of rapid motor patterns in so-cial communication. First, focal lizards were tested in discrimination trials using random-dot kine-matograms displaying combinations of speed, coherence, and direction. Second, we measuredsubject lizards＇ ability to predict the appearance of a secondary reinforcer （1 of 3 differentcomputer-generated animations of invertebrates： cricket, spider, and mite） based on the directionof movement of a field of drifting dots by following a set of behavioural responses （e.g., orientingresponse, latency to respond） to our virtual stimuli. We found an effect of both speed and coher-ence, as well as an interaction between these 2 factors on the perception of moving ***, our results showed that Jacky dragons have acute sensitivity to high speeds. We then em-ployed an optic flow analysis to match the performance to ecologically relevant motion. Our resultssuggest that the Jacky dragon visual system may have been shaped to detect fast motion. Thispre-existing sensitivity may have constrained the evolution of conspecific displays. In contrast,Jacky dragons may have difficulty in detecting the movement of ambush predators, such as snakesand of some invertebrate prey. Our study also demonstrates the potential of the computer-animated stimuli technique for conducting nonintrusive tests to explore motion range and sensitiv-ity in a visually mediated species.

关键词： Amphibolurus muricatus, Jacky dragon, motion sensitivity, random-dot kinematograms, signal evolution, virtualstimuli.

Relationship Between Built Environment, Socio-economic Factors and Carbon Emissions from Shopping Trip in Shenyang City, China

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Chinese Geographical Science 2017年第5期27卷 722-734页

作者： LI Jing LO kevin ZHANG Pingyu GUO Meng Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Department of Geography Hong Kong Baptist University School of Geographical Science Northeast Normal University

Promoting active travel behavior and decreasing transport-related carbon dioxide （CO2） emissions have become a priority in many Chinese cities experiencing rapid urban sprawl and greater automobile dependence. However, there are few studies that holistically examine the physical and social factors associated with travel CO2 emissions. Using a survey of 1525 shoppers conducted in Shenyang, China, this study estimated shopping-related travel CO2 emissions and examined how the built environment and individual socioeconomic characteristics contribute to shopping travel behavior and associated C02 emissions. We found that, firstly, private car trips generate nearly eight times more carbon emissions than shopping trips using public transport, on average. Second, there was sig- nificant spatial autocorrelation with CO2 emissions per trip, and the highest carbon emissions were clustered in the inner suburbs and between the first and second circumferential roads. Third, shopping travel CO2 emissions per trip were negatively correlated with sev- eral built environment features including population density, the quantity of public transport stations, road density, and shop density. They were also found to be significantly related to the individual socio-eeonomic characteristics of car ownership, employment status, and education level using a multinomial logistic regression model. These empirical findings have important policy implications, assisting in the development of measures that contribute to the sustainability of urban transportation and meet carbon mitigation targets.

关键词： transport carbon emission travel behavior built environment socio-economic factors shopping trips China

The effects of sun exposure on carotenoid accumulation and oxidative stress in the retina of the House Finch(Haemorhous mexicanus)

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Chinese Birds 2016年第1期7卷 56-67页

作者： Matthew B.Toomey kevin J.McGraw School of Life Sciences Arizona State University Department of Pathology and Immunology Washington University Medical School

Background: Diet-derived carotenoid pigments are concentrated in the retinas of birds and serve a variety of functions, including photoprotection. In domesticated bird species(e.g., chickens and quail), retinal carotenoid pigmentation has been shown to respond to large manipulations in light exposure and provide protection against photodamage. However, it is not known if or how wild birds respond to ecologically relevant variation in sun ***: We manipulated the duration of natural sunlight exposure and dietary carotenoid levels in wild-caught captive House Finches(Haemorhous mexicanus), then measured carotenoid accumulation and oxidative stress in the ***: We found no significant effects of sun exposure on retinal levels of carotenoids or lipid peroxidation, in replicate experiments, in winter(Jan–Mar) and spring/summer(May–June). Dietary carotenoid supplementation in the spring/summer experiment led to significantly higher retinal carotenoid levels, but did not affect lipid peroxidation. Carotenoid levels differed significantly between the winter and spring/summer experiments, with higher retinal and lower plasma carotenoid levels in birds from the later ***: Our results suggest that variation in the duration of exposure to direct sunlight have limited influence on intraspecific variation in retinal carotenoid accumulation, but that accumulation may track other seasonal–environmental cues and physiological processes.

关键词： Carotenoids Haemorhous mexicanus House Finch Photostress Vision

Prediction of Weyl semimetal and antiferromagnetic topological insulator phases in Bi_(2)MnSe_(4)

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npj Computational Materials 2019年第1期5卷 867-873页

作者： Sugata Chowdhury kevin F.Garrity Francesca Tavazza Materials Measurement Laboratory National Institute for Standards and TechnologyGaithersburgMD 20899USA

Three-dimensional materials with strong spin–orbit coupling and magnetic interactions represent an opportunity to realize a variety of rare and potentially useful topological phases with broken time-reversal *** this work,we use first principles calculations to show that the recently synthesized material Bi_(2)MnSe_(4) displays a combination of spin–orbit-induced band inversion,also observed in non-magnetic topological insulator Bi2PbSe4,with magnetic interactions,leading to several topological *** bulk form,the ferromagnetic phase of Bi_(2)MnSe_(4) has symmetry protected band crossings at the Fermi level,leading to either a nodal line or Weyl semimetal,depending on the direction of the *** to the combination of time reversal symmetry plus a partial translation,the ground state layered antiferromagnetic phase is instead an antiferromagnetic topological *** surface of this phase intrinsically breaks time-reversal symmetry,allowing the observation of the half-integer quantum anomalous Hall ***,we show that in thin film form,for sufficiently thick slabs,Bi_(2)MnSe_(4) becomes a Chern insulator with a band gap of up to 58 *** combination of properties in a stoichiometric magnetic material makes Bi_(2)MnSe_(4) an excellent candidate for displaying robust topological behavior.

关键词： topological insulator symmetry

Spatial Patterns of Car Sales and Their Socio-economic Attributes in China

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Chinese Geographical Science 2017年第5期27卷 684-696页

作者： LIU Daqian LO kevin SONG Wei XIE Chunyan Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China Department of Geography Hong Kong Baptist UniversityHong Kong 999077China Department of Geography and Geosciences University of LouisvilleLouisville KY 40292USA FAW-Volkswagen Automotive Company Ltd. Changehun 130061China

Using data from the Economic Advisory Center of the State Information Center(SIC), we examined the spatial patterns of car sales in China at the prefectural level in 2012. We first analyzed the spatial distributions of car sales of different kinds of automakers(foreign automakers, Sino-foreign joint automakers, and Chinese automakers), and then identified spatial clusters using the local Moran's indexes. Location quotient analysis was applied to examine the relative advantage of each type of automaker in the local markets. To explain the variations of car sales across cities, we collected several socioeconomic variables and conducted regression analyses. Further, factor analysis was used to extract independent variables to avoid the problem of multicollinearity. By incorporating a spatial lag or spatial error in the models, we calibrated our spatial regression models to address the spatial dependence problem. The analytical results show that car sales varied significantly across cities in China, and most of the cities with higher car sales were the developed cities. Different automakers exhibit diverse spatial patterns in terms of car sales volume, spatial clusters, and location quotients. The scale and incomes factor were extracted and verified as the two most significant and positive factors that shape the spatial distributions of car sales, and together with the spatial effect, explained most of the variations of car sales across cities.

关键词： car sales spatial clusters Location Quotient socio-economic attributes China

Drought Planning Research in the United States: An Overview and Outlook

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International Journal of Disaster Risk Science 2013年第2期4卷 51-58页

作者： Xinyu Fu Zhenghong Tang Jianjun Wu kevin McMillan Community and Regional Planning Program College of ArchitectureUniversity of Nebraska-LincolnLincolnNE 68588USA Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875China School of Natural Resources University of Nebraska-LincolnLincolnNE 68588USA

Drought is widely known as an insidious hazard due to its complex and unique characteristics. Drought disasters have brought tremendous economic losses and significant social and environmental impacts to communities across the globe. To further understand the hazard drought poses and provide insights into planning for drought preparedness, this article conducts a thorough literature review of drought hazard and drought planning frameworks within the United States. Two main approaches and three major forms of drought planning are discussed and summarized. Based on this review, a preliminary overview of drought planning status in the United States is presented. This study provides insight into major drought planning literature and establishes a link with drought mitigation and adaptation. The article concludes with discussion and implication for future drought planning and a future research outlook.

关键词： drought hazard insight

Virtual screening of inorganic materials synthesis parameters with deep learning

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npj Computational Materials 2017年第1期3卷 14-22页

作者： Edward Kim kevin Huang Stefanie Jegelka Elsa Olivetti Department of Materials Science and Engineering MITCambridgeMAUSA Department of EECS and CSAIL MITCambridgeMAUSA

Virtual materials screening approaches have proliferated in the past decade,driven by rapid advances in first-principles computational techniques,and machine-learning *** comparison,computationally driven materials synthesis screening is still in its infancy,and is mired by the challenges of data sparsity and data scarcity:Synthesis routes exist in a sparse,highdimensional parameter space that is difficult to optimize over directly,and,for some materials of interest,only scarce volumes of literature-reported syntheses are *** this article,we present a framework for suggesting quantitative synthesis parameters and potential driving factors for synthesis *** use a variational autoencoder to compress sparse synthesis representations into a lower dimensional space,which is found to improve the performance of machine-learning *** realize this screening framework even in cases where there are few literature data,we devise a novel data augmentation methodology that incorporates literature synthesis data from related materials *** apply this variational autoencoder framework to generate potential SrTiO_(3) synthesis parameter sets,propose driving factors for brookite TiO_(2) formation,and identify correlations between alkali-ion intercalation and MnO_(2) polymorph selection.

关键词： synthesis variational inorganic

Feedback Control for Ecosystem Management:The Case of Wolf-Elk-Hunting Dynamics in the US Mountain West

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Journal of Mountain Science 2014年第4期11卷 850-865页

作者： kevin MACKSAMIE Jeffrey WAGNER Juan C.COCKBURN Black River Systems Company Inc. 162 Genesee Street Utica New York 13507 USA Department of Economics Rochester Institute of Technology 92 Lomb Memorial Drive Rochester NY 14623 USA Department of Computer Engineering Rochester Institute of Technology 83 Lomb Memorial Drive Rochester NY 14623USA

The purpose of this paper is to explore the promise of utilizing some relatively new feedback control techniques in ecosystem management. First, we set forth a basic ecological-economic model of a predator-prey-hunting system in which both the predator and prey have use(flow) and non-use(stock) value and when the predator can inflict transboundary damages. We then use new data from the US Mountain West to show how a particular feedback approach—linear parameter-varying(LPV) control—can be utilized in this context. Our LPV model is able to quantify the cost of managing disturbances that inevitably arise as a manager tries to keep the actual path of the system "close" to its optimum. The results suggest management strategies in mountain ecosystems that feature large, mammalian carnivores.

关键词： Feedback control Linear parameter Optimal vontrol Robust control Predator-prey Recreational hunting

Digestive retention times for Allen’s swamp monkey and L’Hoest’s monkey: data with implications for the evolution of cercopithecine digestive strategy

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Integrative Zoology 2012年第2期7卷 183-191页

作者： kevin P.BLAINE Joanna E.LAMBERT Department of Anesthesia Stanford University Medical CenterStanfordCaliforniaUSA Department of Ecological Anthropology University of Texas at San AntonioSan AntonioTexasUSA

Primates access energy from plant fiber via bacterial fermentation in either a modified forestomach(‘foregut’),a caecocolic(‘hindgut’)chamber of the large intestine,or *** digestive retention times allow for more complete fermentation;as such,primates that consume an herbivorous diet high in fiber are expected to have both relatively and absolutely longer retention times than those mammals that rely on more readily digestible plant foods,such as *** used particulate markers to measure the digestive retention times of captive Allen’s swamp monkeys[Allenopithecus nigroviridis(Pocock,1907)](n=3)and L’Hoest’s monkey(Cercopithecus lhoesti ***,1899)(n=2).Results indicate mean retention times of 23.2-29.4 h and 23.2-24.0 h for *** and ***,*** from this study,in combination with previously published data on digestive retention times in other primate species,indicate that cercopithecines differ from other primate taxa by having lengthier retention times that can be predicted by body mass *** data are consistent with the hypothesis that relatively lengthy retention times are a primitive trait for Cercopithecinae.

关键词： Cercopithecinae digestive retention time evolution of diet fermentation plant fiber