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Variation in sexual dimorphism and assortative mating do not predict genetic divergence in the sexually dimorphic Goodeid fish Girardinichthys multiradiatus

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current Zoology 2012年第3期58卷 440-452页

作者： c. MAcIAS GARcIA G smith c. GONZALEZ ZUARTH J. A. GRAVES M. G. RITcHIE Departamento de Ecologia Evolutiva Instituto de Ecologia UNAM A. E 70-275 C. E 04510 M6xico DE M6xico School of Biology University of St Andrews St Andrews Fife KY16 9TH Scotland UK

Sexual dimorphism is often used as a proxy for the intensity of sexual selection in comparative studies of sexual selection and diversification. The Mexican Goodeinae are a group of livebearing freshwater fishes with large variation between species in sexual dimorphism in body shape. Previously we found an association between variation in morphological sexual dimorphism between species and the amount of gene flow within populations in the Goodeinae. Here we have examined if mor- phological differentiation within a single dimorphic species is related to assortative mating or gene flow between populations. In the Amarillo fish Girardinichthys multiradiatus studies have shown that exaggerated male fins are targets of female preferences. We find that populations of the species differ in the level of sexual dimorphism displayed due to faster evolution of differences in male than female morphology. However, this does not predict variation in assortative mating tests in the laboratory; in fact dif- ferences in male morphology are negatively correlated with assortative mating. Microsatellite markers reveal significant genetic differences between populations. However, gene flow is not predicted by either morphological differences or assortative mating. Rather, it demonstrates a pattern of isolation by distance with greater differentiation between watersheds. We discuss the caveats of predicting behavioural and genetic divergence from so-called proxies of sexual selection [current Zoology 58 （3）： 440-452, 2012].

关键词： Sexual dimorphism Assortative mating Genetic distance Speciation Viviparous fish

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Prediction of dispersed phase holdup in pulsed disc and doughnut solvent extraction columns under different mass transfer conditions

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chinese Journal of chemical Engineering 2016年第2期24卷 226-231页

作者： Yong Wang Kathryn H.smith Kathryn Mumford Teobaldo f.Grabin Zheng Li Geoffrey W.Stevens Particulate fluids Processing centre Department of Chemical and Biomolecular EngineeringThe University of Melbourne

Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns （PDDc） have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDc has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDc were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. chem. Res.,27 （1988）,131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDc （i.e. the plate spacing）, the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. chem. Res.,34 （1995） 3925-3940] was refitted to the PDDc data. New constants have been presented for each hold- up correlation for a PDDc based on regression analysis using published holdup data from PDDcs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer.

关键词： Solvent extraction Liquid extraction Pulsed disc and doughnut columns Solvent extraction column design Holdup Dispersed phase holdup Hydrodynamics of extraction columns

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Early Results of Urothelial carcinoma Screening in a Risk Population of coke Workers:Urothelial carcinoma among coke Workers

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Biomedical and Environmental Sciences 2010年第4期23卷 300-304页

作者： GIBERTI c GALLO f ScHENONE M GENOVA A Department of Surgery Division of Urology San Paolo Hospital Savona Italy Service of Industrial Medicine Italiana Coke Industry S.r.l

Objective To present the protocol and the early results of a urothelial carcinoma （Uc） screening analysis performed in a risk population of coke workers. Methods Between June 2006 and October 2008, 171 male workers （mean age 43 years）, employed in a Ligurian coke plant （Italiana coke S.r.l） and exposed to polycyclic aromatic hydrocarbons （PAHs） for a median period of 16 years, underwent screening for Uc. Urological evaluation included medical history, physical examination, routine laboratory tests, urine analysis, urinary cytology and ucyt＋ assay. In the event of signs and symptoms suggestive of Uc or positive urinary tests, the workers were also subjected to urinary ultrasonography and cystoscopy with biopsy of any suspicious lesions. Results Regarding the laboratory tests, 19/171 （11%） ucyt＋ samples were considered inadequate and were excluded from the outcomes assessment. Overall, urine analysis, cytology and ucyt＋ were positive in 18/152 （12%） subjects who showed no evidence of Uc at the scheduled check-ups. No significant association was identified between marker positivity and occupational activity. conclusions Our results fail to show an increased risk of Uc among the coke workers evaluated. However, they will need to be confirmed in the future by a larger enrollment and a longer follow-up in order to assess the definitive risk for Uc after exposure to coke.

关键词： Bladder cancer Screening Occupation Risk factor Urinary markers

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Modelling the daily risk of Ebola in the presence and absence of a potential vaccine

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Infectious Disease Modelling 2020年第1期5卷 905-917页

作者： Stéphanie M.c.Abo Robert smith Department of Applied Mathematics The University of WaterlooWaterlooCanada Department of Mathematics and faculty of Medicine The University of Ottawa150 Louis-Pasteur PvtOttawaONK1N6N5Canada

Ebola virus d one of the deadliest viral diseases,with a mortality rate around 90%d damages the immune system and organs,with symptoms including episodic fever,chills,malaise and *** Recombinant Vesicular Stomatitis Virus-based candidate vaccine(rVSV-ZEBOV)has demonstrated clinical efficacy against Ebola in ring-vaccination clinical *** order to evaluate the potential effect of this candidate vaccine,we developed risk equations for the daily risk of Ebola infection both currently and after *** risk equations account for the basic transmission probability of Ebola and the lowered risk due to various protection protocols:vaccination,hazmat suits,reduced contact with the infected living and dead *** space was sampled using Latin Hypercube Sampling,a statistical method for generating a near-random sample of parameter *** found that at a high transmission rate of Ebola(i.e.,if the transmission rate is greater than 90%),a large fraction of the population must be vaccinated(>80%)to achieve a 50%decrease in the daily risk of *** a vaccine is introduced,it must have at least 50%efficacy,and almost everyone in the affected areas must receive it to effectively control outbreaks of *** results indicate that a low-efficacy Ebola vaccine runs the risk of having vaccinated people be overconfident in a weak vaccine and hence the possibility that the vaccine could make the situation worse,unless the population can be sufficiently educated about the necessity for high vaccine uptake.

关键词： Ebola virus disease Mathematical model Risk equations Latin hypercube sampling Eradication

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Inherent complexities of a Multi-stakeholder Approach to Building community Resilience

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International Journal of Disaster Risk Science 2020年第1期11卷 32-45页

作者： Josephine Adekola Denis fischabcher-smith Moira fischabcher-smith finance Accounting and RiskGlasgow Caledonian UniversityGlasgow G40BAScotlandUK college of Social Sciences University of GlasgowGlasgow G128QQScotlandUK

Enhancing community resilience has increasingly involved national and regional governments adopting a multi-stakeholder approach because of the potential interagency benefits. This has led to questions about how best to involve stakeholder groups in translating community resilience policies into practice. This exploratory study contributes to this discussion by addressing two key areas that are fundamental in the concerted effort to build community resilience to natural hazards:(1) stakeholder understanding of community resilience as a concept;and(2) the difficulties associated with the processes of risk assessment and preparedness that stakeholders face locally in building community resilience. Data were collected through semistructured interviews with 25 practitioners and experts within Scotland’s resilience community, and were analyzed through an inductive approach to thematic analysis. These data show how the interpretation of community resilience differs across stakeholder groups. Analysis of the data reveals challenges around the nature of the risk assessment and its role in shaping risk perception and communication. Significant complications occur in communicating about low probability-high consequence events, perceived territoriality, competing risk prioritizations, and the challenges of managing hazards within a context of limited resources. The implications of these issues for policy and practice are also discussed.

关键词： community disaster preparedness community resilience Multi-stakeholder approach Natural hazards Risk assessment

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computer-aided morphometry of liver inflammation in needle biopsies

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World Journal of Gastroenterology 2005年第44期11卷 6995-7000页

作者： N Dioguardi B franceschini c Russo f Grizzi Scientific Direction

AIM: To introduce a computer-aided morphometric method for quantifying the necro-inflammatory phase in liver biopsy specimens using fractal geometry and Delaunay's ***: Two-micrometer thick biopsy sections taken from 78 chronic hepatitis c virus-infected patients were immunohistochemically treated to identify the inflammatory cells. An automatic computer-aided image analysis system was used to define the inflammatory cell network defined on the basis of Delaunay's triangulation,and the inflammatory cells were geometrically classified as forming a cluster (an aggregation of a minimum of three cells) or as being irregularly distributed within the tissue. The phase of inflammatory activity was estimated using Hurst's ***: The proposed automatic method was rapid and objective. It could not only provide rigorous results expressed by scalar numbers, but also allow the state of the whole organ to be represented by Hurst's exponent with an error of no more than 12%.cONcLUSION: The availability of rigorous metrical measures and the reasonable representativeness of the status of the organ as a whole raise the question as to whether the indication for hepatic biopsy should be revised by establishing clear rules concerning the contraindications suggested by its invasiveness and subjective interpretation.

关键词： Biopsy Grading Image analysis fractal geometry Topography Delaunay

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Variable retention harvesting in the Douglas-fir region

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Ecological Processes 2020年第1期9卷 83-92页

作者： Jerry f.franklin Daniel c.Donato School of Environmental and forest Science College of the EnvironmentUniversity of WashingtonSeattleWA 98195USA Washington Department of Natural Resources OlympiaWA 98504USA

Variable retention harvesting evolved in the Douglas-fir region of the Pacific Northwest gradually in response to increasing dissatisfaction with the ecological consequences of clear-cutting,from the standpoint of wildlife habitat and other important forest *** is a harvesting technique that can provide for retention(continuity)of such structures as large and old live trees,snags,and *** retention is based on the natural model of the biological legacies that are typically left behind following natural disturbances,such as wildfire,wind,and *** retention is also an important technique for fulfilling the first silvicultural principle of ecological forestry,that of providing for continuity in structure,function,and composition between forest *** history and current application of variable retention approaches on forests in western Washington and Oregon states(USA),where many of the fundamental concepts were first developed and applied,is described in this article.

关键词： Biological legacies Ecological forestry Biodiversity conservation Long-term sustainability Washington and Oregon states

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Modelling and mapping third dimension in a spatial database

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International Journal of Digital Earth 2011年第6期4卷 505-520页

作者： f.Donera c.Bıyık Department of Geomatics Engineering Gumushane UniversityGumushaneTurkey Department of Geomatics Engineering Karadeniz Technical UniversityTrabzonTurkey

In this paper,an overview of phases for modelling and mapping third dimension of spatial objects in a database is presented based on a selected spatial database management system(DBMS).These phases include(1)defining a spatial reference system for representing three-dimensional(3D)objects with real-world coordinates,(2)geometric modelling of 3D objects in the database,(3)3D spatial indexing for fast accessing/querying the 3D data,3D spatial queries and representation of 3D ***,a case study is performed to assess needs,possibilities and potential limitations of 3D data modelling in the spatial database.

关键词： spatial database geo-data 3D data modelling GIS digital earth

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Strain Hardening and Strain Rate Sensitivity Behaviors of Advanced High Strength Steels

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Journal of Iron and Steel Research International 2013年第6期20卷 68-74页

作者： f Ozturk A Polat S Toros R c Picu Department of Mechanical Engineering Nigde University Department of Mechanical Aerospace and Nuclear Engineering Rensselaer Polytechnic InstituteTroy 12180 New York USA

The mechanical properties of commercial dual phase （DP）, transformation induced plasticity （TRIP）, and high strength low alloy （HSLA-340） steel sheets are investigated and compared at various strain rates ranging from 0.001 7to 0.17 s-1 at ambient *** steel outperforms the other two materials , having comparable ductility and twice as large strength relative to DP *** has larger strength and much larger ductility than *** exceuent ductility of TRIP800is due to its high strain hardening capability , which promotes stable plastic *** is observed that the strain hardening rate in TRIP800does not decrease to zero at failure , as common in most materials in which failure is preceded by necking.

关键词： steel advanced high strength steel HSLA DP TRIP hardening

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Novel Heat Transfer Issues Associated with the Design and Safe Operation of the MEGAPIE Spallation Source Target

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Journal of Thermal Science 2007年第1期16卷 63-78页

作者： Brian L.smith Thermal Hydraulics Laboratory Paul Scherrer InstituteSwitzerland

critical heat transfer problems are discussed in the context of the operation of a spallation source target, which represents a first demonstration of the feasibility of an innovative concept for generating energy using a particle accelerator. Within the framework of the umbrella project MEGAPIE, an R＆D support group was organized to take responsibility for target cooling. This involved the use of advanced numerical methods - computational fluid Dynamics （cfD） and finite Element Method （fEM） - validated against suitable experimental data, and by means of appropriate benchmarking exercises. The design studies using cfD resulted in an optimum flow configuration being defined for the coolant circulation. flow visualization tests were undertaken using a glass/water test section, with the velocity field mapped using optical and ultrasonic measuring techniques. These were followed by heat transfer tests, using the actual target materials （lead-bismuth-eutectic coolant and steel confinement）. further cfD/fEM work to analyze operational transients and accident sequences was also carded out, and is described in the paper.

关键词： computational fluid dynamics finite element method liquid-metal coolant spallation source target

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