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competition for food in 2 populations of a wild-caught fish

current Zoology 2018年第5期64卷 615-622页

作者： pierre j.c. chuard Grant E. BROWN james W.A. GRANT Research School of Biology The Australian National University Canberra ACT 0200 Australia Departmentof Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec Canada H4B 1R6

Aggressive behavior when competing for resources is expected to increase as the ratio of competitors-to-resource ratio （cRR） units increases. Females are expected to be more aggressive than males when competing for food when body size is more strongly related to reproductive suc- cess in females than in males, whereas aggression is predicted to decrease under high ambient predation risk by natural selection. Under the risk allocation model, however, individuals under high ambient predation risk are expected to be more aggressive, and forage more in the absence of imminent risk than their low risk counterparts. An interaction between adult sex ratio （i.e., adult males/females）, ambient predation risk （high vs. low）, and sex on intrasexual competition for mates in Trinidadian guppies Poecilia reticulata has been shown. The interaction suggested an increase in aggression rates as cRR increased, except for males from the high predation population. To compare the patterns of competition for food versus mates, we replicated this study by using food patches. We allowed 4 male or 4 female guppies from high and low predation populations to com- pete for 5, 3, or 1 food patches. The foraging rate was higher in a high rather than low ambient pre- dation risk population. Surprisingly, cRR, sex, and population of origin had no effect on aggression rates. Despite other environmental differences between the 2 populations, the effect of ambient predation risk may be a likely explanation for differences in foraging rates. These results highlight the importance for individuals to secure food despite the cost of competition and predation.

关键词： aggression competitor-to-resource ratio foraging Poecifia reticulata population differences predation risk sex

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Local predation risk shapes spatial and foraging neophobia patterns in Trinidadian guppies

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current Zoology 2016年第5期62卷 457-462页

作者： chris K. ELVIDGE pierre j.c. chuard Grant E. BROWN Department of Biology Concordia University 7141 Sherbrooke St. West Montreal QC H4B 1R6 Canada

The ＂dangerous niche＂ hypothesis posits that neophobia functions to reduce the cost of habitat use among animals exposed to unknown risks. For example, more dangerous foraging or higher competi- tion may lead to increased spatial neophobia. Likewise, elevated ambient predation threats have been shown to induce phenotypically plastic neophobic predator avoidance. In both cases, neophobia is argued to reduce the cost of living associated with ecological uncertainty. Here, we test the hypothesis that ambient predation shapes both neophobic predator avoidance and spatial and foraging neophobia in Trinidadian guppies. Guppies were exposed to a novel foraging arena paired with a known cue （conspecific alarm cue）, a novel cue （lemon odor）, or a stream water control in three streams differing in ambient predation risk. We demonstrate that guppies from a high-predation-risk stream exhibited risk-averse foraging patterns regardless of the chemical stimulus presented （high spatial neophobia） and that those from a low-predation-risk stream were only risk-averse when the foraging arenas were paired with conspecific alarm cue （lower spatial neophobia）. Those tested in the intermediate- predation-risk stream were consistently intermediate to the high-risk vs. low-risk populations. Our study suggests that ambient predation risk shapes both neophobic predator avoidance and space-use pat- terns and that neophobia may function as a ＂generalized＂ response to ecological uncertainty.

关键词： phenotypic plasticity predator recognition foraging predator recognition predator-prey interactions Trinidadian guppies.

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Biomarkers in Barrett's esophagus and esophageal adenocarcinoma:Predictors of progression and prognosis

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World journal of Gastroenterology 2010年第45期16卷 5669-5681页

作者： chin-Ann j Ong pierre Lao-Sirieix Rebecca c Fitzgerald MRc cancer cell Unit Hutchison-MRC Research CentreCambridgeCB20XZUnited Kingdom

Barrett’s esophagus is a well-known premalignant lesion of the lower esophagus that is characterized by intestinal metaplasia of the squamous epithelium. It is clinically important due to the increased risk (0.5% per annum) of progression to esophageal adenocarcinoma (EA), which has a poor outcome unless diagnosed early. The current clinical management of Barrett’s esophagus is hampered by the lack of accurate predictors of progression. In addition, when patients develop EA, the current staging modalities are limited in stratifying patients into different prognostic groups in order to guide the optimal therapy for an individual patient. Biomarkers have the potential to improve radically the clinical management of patients with Barrett’s esophagus and EA but have not yet entered mainstream clinical practice. This is in contrast to other cancers like breast and prostate for which biomarkers are utilized routinely to inform clinical decisions. This review aims to highlight the most promising predictive and prognostic biomarkers in Barrett’s esophagus and EA and to discuss what is required to move the field forward towards clinical application.

关键词： Barrett’s esophagus Esophageal adenocar cinoma Esophageal dysplasia Prognosis

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An integrated approach to site-specific management zone delineation

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Frontiers of Agricultural Science and Engineering 2018年第4期5卷 432-441页

作者： Yuxin MIAO David j.MULLA pierre c.ROBERT Precision Agriculture center Department of SoilWater and ClimateUniversity of Minnesota

Dividing fields into a few relatively homogeneous management zones(MZs) is a practical and costeffective approach to precision agriculture. There are three basic approaches to MZ delineation using soil and/or landscape properties, yield information, and both sources of information. The obj.c.ive of this study is to propose an integrated approach to delineating site-specific MZ using relative elevation, organic matter, slope, electrical conductivity, yield spatial trend map, and yield temporal stability map(ROSE-YSTTS) and evaluate it against two other approaches using only soil and landscape information(ROSE) or clustering multiple year yield maps(cMYYM). The study was carried out on two no-till corn-soybean rotation fields in eastern Illinois, USA. Two years of nitrogen(N) rate experiments were conducted in Field B to evaluate the delineated MZs for site-specific N management. It was found that in general the ROSE approach was least effective in accounting for crop yield variability(8.0%–9.8%), while the cMYYM approach was least effective in accounting for soil and landscape(8.9%–38.1%), and soil nutrient and pH variability(9.4%–14.5%). The integrated ROSE-YSTTS approach was reasonably effective in accounting for the three sources of variability(38.6%–48.9%, 16.1%–17.3% and 13.2%–18.7% for soil and landscape, nutrient and pH, and yield variability, respectively), being either the best or second best approach. It was also found that the ROSE-YSTTS approach was effective in defining zones with high,medium and low economically optimum N rates. It is concluded that the integrated ROSE-YSTTS approach combining soil, landscape and yield spatial-temporal variability information can overcome the weaknesses of approaches using only soil, landscape or yield information,and is more robust for MZ delineation. It also has the potential for site-specific N management for improved economic returns. More studies are needed to further evaluate their appropriateness for precision N

关键词： economically optimum nitrogen rate fuzzy cluster analysis precision nitrogen management site-specific management soil landscape property yield map

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InterStoreDB:A Generic Integration Resource for Genetic and Genomic Data

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journal of Integrative Plant Biology 2012年第5期54卷 345-355页

作者： christopher G. Love Ambrose E. Andongabo jun Wang pierre W. c. carion christopher j.Rawlings Graham j. King Ludwig Institute for cancer Research Centre for Medical Research Royal Melbourne Hospital Royal Parade Parkville Victoria 3050 Australia Department of Biomathematics and Bioinformatics Rothamsted Research Harpenden Herts AL5 2JQ UK Queen Mary University of London Charterhouse Square London EC1M 6BQ UK Southern cross Plant Science Southern Cross University P.O. Box 157 Lismore NSW 2480 Australia

Associating phenotypic traits and quantitative trait loci （QTL） to causative regions of the underlying genome is a key goal in agricultural research. InterStoreDB is a suite of integrated databases designed to assist in this process. The individual databases are species independent and generic in design, providing access to curated datasets relating to plant populations, phenotypic traits, genetic maps, marker loci and QTL, with links to functional gene annotation and genomic sequence data. Each component database provides access to associated metadata, including data provenance and parameters used in analyses, thus providing users with information to evaluate the relative worth of any associations identified. The databases include cropStoreDB, for management of population, genetic map, QTL and trait measurement data, SeqStoreDB for sequence-related data and AlignStoreDB, which stores sequence alignment information, and allows navigation between genetic and genomic datasets. Genetic maps are visualized and compared using the cMAP tool, and functional annotation from sequenced genomes is provided via an EnsEMBL-based genome browser. This framework facilitates navigation of the multiple biological domains involved in genetics and genomics research in a transparent manner within a single portal. We demonstrate the value of InterStoreDB as a tool for Brassica research. InterStoreDB is available from： http：//***

关键词： QTL bioinformatics databases.

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isoAOT40:An improved ozone exposure index based on the Annual Ozone Spectrum Profile(AO3SP)

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journal of Forestry Research 2022年第6期33卷 1949-1955页

作者： Evgenios Agathokleous costas j.Saitanis Stefanos Agathokleous chrysanthos Savvides Vicent calatayud pierre Sicard collaborative Innovation center On Forecast and Evaluation of Meteorological Disasters(cIc-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044People’s Republic of China Research center for Global changes and Ecosystem carbon Sequestration&Mitigation School of Applied MeteorologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Lab of Ecology and Environmental Science Agricultural University of AthensIera Odos 7511855 AthensGreece The cyprus Institute NicosiaCyprus Department of Labour Inspection Ministry of Labour and Social InsuranceNicosiaCyprus Fundación cEAM Parque TecnológicoC/Charles R.Darwin14PaternaSpain ARGANS 260 route du Pin MontardBiotFrance

Abstarct In recognition of the rising threats of groundlevel ozone(O_(3))pollution to forests,agricultural crops,and other types of vegetation,accurate and realistic risk assessment is urgently *** accumulated O_(3)exposure over a concentration threshold of 40 nmol mol-1(AOT40)is the most commonly used metric to investigate O3 exposure and its effects on vegetation and to conduct vegetation risk *** is also used by international regulatory authorities for deriving critical levels and setting standards to protect vegetation against surface O_(3).However,fixed periods of the growing season are used universally,yet growing seasons vary with latitudes and elevations,and the periods of plant lifespan also differ among annual ***,we propose the concept of the Annual O_(3)Spectrum Profile(AO_(3)SP)and apply it to calculate the profile of AOT40 throughout the year(AAOT40SP,Annual AOT40 Spectrum Profile)using the International Organization for Standardization(ISO)weeks as a shorter window ISO-based accumulated *** moving time periods of three(for crops)or six(for forests)months,the i so AOT40 behavior throughout the year can be examined as a diagnostic tool for O_(3)risks in the short-or long-term during the lifecycle of local *** this analysis,AOT40(i so AOT40)that is most representative for the local conditions and specific situations can be identified,depending on the exact growing season and lifecycle of the target *** applied this novel approach to data from five background monitoring stations located at different elevations in *** results show that the AAOT40SP approach can be used for improved and more realistic assessment of O3 risks to *** AO_(3)SP approach can also be applied using metrics other than AOT40(exposure-or flux-based),adding a new dimension to the way O_(3)risk to vegetation is assessed.

关键词： Air pollution AOT40 index Ozone risk assessment critical levels Vegetation exposure metric

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Studying beta diversity: ecological variation partitioning by multiple regression and canonical analysis

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journal of Plant Ecology 2008年第1期1卷 3-8页

作者： pierre Legendre Departement de sciences biologiques Universite´de Montre´alCP 6128succursale Centre-villeMontre´alQue´becCanada H3C 3J7

Aims Beta diversity is the variation in species composition among sites in a geographic *** diversity is a key concept for understanding the functioning of ecosystems,for the conservation of biodiversity and for ecosystem *** present report describes how to analyse beta diversity from community composition and associated environmental and spatial data *** Beta diversity can be studied by computing diversity indices for each site and testing hypotheses about the factors that may explain the variation among ***,one can carry out a direct analysis of the community composition data table over the study sites,as a function of sets of environmental and spatial *** analyses are carried out by the statistical method of partitioning the variation of the diversity indices or the community composition data table with respect to environmental and spatial *** partitioning is briefly described *** findings Variation partitioning is a method of choice for the interpretation of beta diversity using tables of environmental and spatial *** diversity is an interesting‘currency’for ecologists to compare either different sampling areas or different ecological communities cooccurring in an *** must be based upon unbiased estimates of the variation of the community composition data table that is explained by the various tables of explanatory *** adjusted coefficient of determination provides such an unbiased estimate in both multiple regression and canonical redundancy *** partitioning,one can test the significance of the fractions of interest and plot maps of the fitted values corresponding to these fractions.

关键词： Adjusted coefficient of determination beta diversity biodiversity canonical redundancy analysis community composition variation partitioning

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Volumetric Vector-Based Representation for Indirect Illumination caching

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journal of computer Science & Technology 2010年第5期25卷 925-932页

作者： Romain Pacanowski Xavier Granier christophe Schlick pierre Poulin cEA-cESTA BP2 Le Barp33114France AcM INRIA Bordeaux Sud-Ouest/LaBRI-Bordeaux University Talence33405France State Key Lab of cAD&cG Zhejiang University LIGUM Dept.I.R.O.Universite de MontrealMontreal QCH3C 3J7Canada

This paper introduces a caching technique based on a volumetric representation that captures low-frequency indirect *** structure is intended for efficient storage and manipulation of *** is based on a 3D grid that stores a fixed set of irradiance *** preprocessing,this representation can be built using almost any existing global illumination *** rendering,the indirect illumination within a voxel is interpolated from its associated irradiance vectors,and is used as additional local light *** with other techniques,the 3D vector-based representation of our technique offers increased robustness against local geometric variations of a *** thus demonstrate that it may be employed as an efficient and high-quality caching data structure for bidirectional rendering techniques such as particle tracing or photon mapping.

关键词： caching for global illumination photon mapping particle tracing

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An Efficient Bio-inspired Oxygen Reduction Reaction catalyst:MnO_(x)Nanosheets Incorporated Iron Phthalocyanine Functionalized Graphene

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能源与环境材料（英文） 2021年第3期4卷 474-480页

作者： Xing Wu Yi cheng jean-pierre Veder San Ping jiang Department of Environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China National Engineering Technology Research center for control and Treatment of Heavy-metal Pollution Changsha 410083China john de Laeter centre Curtin UniversityPerth WA 6102Australia Fuels and Energy Technology Institute Curtin UniversityPerth WA 6102Australia

Oxygen reduction reaction(ORR)catalysts play a critical role in energy storage and conversion devices and have been attracted enormous interests,and however,it remains challenging to develop highly active cheap catalysts in a simple and green *** by the heme-copper oxidases(HOcs),in which the ORR active center is originated from the incorporation of Fe-N_(4)with copper atom,we here developed a fine manganese oxide nanosheets(MnO_(x)NSs)integrated with iron phthalocyanine(FePc)anchored on highly conductive graphene(MnO_(x)/FePc-G)through a green route only involve ethanol as the *** bio-inspired catalyst MnO_(x)/Fe Pc-G demonstrated high ORR activity with a half-wave potential(E_(1/2))of 0.887 V,about 57 mV more positive than that of Pt/*** the current density(j)at 0.9 V is about 1.9 m A cm^(-2),which is three times of Pt/c and *** importantly,the bio-inspired systems show superior stability in comparison to commercial Pt/c,showing a potential of 0.863 V to deliver a j of 3 mA cm^(-2)after 18000 s polarization,about 80 mV higher than that of 0.783 V for Pt/*** high activity is contributed by the integration of the Fe Pc and MnO_(x)NSs that plays the role to assist the cleavage of the O_(2)*** approach provides a new evidence to develop highly efficient ORR catalysts through imitate the naturally involved systems through a simple route.

关键词： bio-inspired heme-copper oxidases iron phthalocyanine MnO_(x)nanosheets oxygen reduction reaction

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Variance reduction for generalized likelihood ratio method by conditional Monte carlo and randomized Quasi-Monte carlo methods

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journal of Management Science and Engineering 2022年第4期7卷 550-577页

作者： Yijie Peng Michael c.Fu jiaqiao Hu pierre L’Ecuyer Bruno Tuffin Peking University Beijing100871China University of Maryland College ParkMD20742USA Stony Brook University Stony BrookNY11794-3600USA University of Montreal MontrealQuebecH3T 1J4Canada INRIA Univ RennesCNRSIRISACampus de Beaulieu35042Rennes CedexFrance

The generalized likelihood ratio(GLR)method is a recently introduced gradient estimation method for handling discontinuities in a wide range of sample *** put the GLR methods from previous work into a single framework,simplify regularity conditions to justify the unbiasedness of GLR,and relax some of those conditions that are difficult to verify in ***,we combine GLR with conditional Monte carlo methods and randomized quasi-Monte carlo methods to reduce the *** experiments show that variance reduction could be significant in various applications.

关键词： Simulation Stochastic gradient estimation conditional Monte carlo Randomized quasi-Monte carlo

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