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social interactions in a solitary carnivore

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Current Zoology 2017年第4期63卷 357-362页

作者： l. Mark ElBROCH Howard QUIGlEY Panthera 8 West 40th Street 18th Floor New York NY 10018 USA

In total, 177 of 245 terrestrial carnivores are described as solitary, and much of carnivore ecology is built on the assumptions that interactions between adult solitary carnivores are rare. We employed Global Positioning system （GPs） technology and motion-triggered cameras to test predictions of land-tenure territoriality and the resource dispersion hypothesis in a territorial carnivore, the puma Puma concolor. We documented 89 independent GPs interactions, 60% of which occurred at puma kills （n=53）, 59 camera interactions, 11 （17%） of which captured courtship behaviors, and 5 other interactions （1 F-F, 3 M-F, and 1 M-M）. Mean minimum weekly contact rates were 5.5 times higher in winter, the season when elk Cervus elaphus were aggregated at lower elevations and during which puma courtship primarily occurred. In winter, contacts rates were 0.6_＋ 0.3 （standard devi- ation （sD）） interactions/week vs. 0.1 _＋ 0.1 （sD） interactions/week during summer. The preponder- ance of interactions at food sources supported the resource dispersion hypothesis, which predicts that resource fluxes can explain temporary social behaviors that do not result in any apparent benefits for the individuals involved. Conspecific tolerance is logical when a prey is so large that the predator that killed it cannot consume it entirely, and thus, the costs of tolerating a conspecific sharing the kill are less than the potential costs associated with defending it and being injured. Puma aggregations at kills numbered as high as 9, emphasizing the need for future research on what explains tolerance among solitary carnivores.

关键词： carnivores competition Puma concolor resource dispersion hypothesis social interactions tolerance.

Mixed-Vehicular Aggregated Transportation Network Design Considering En-route Recharge service Provision for Electric Vehicles

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Journal of systems science & Complexity 2018年第5期31卷 1329-1349页

作者： ZHANG Xiang WAllER s Travis school of Civil and Environmental Engineering University of New South Wales Australia

This paper addresses the transportation network design problem （NDP） wherein the dis- tance limit and en-route recharge of electric vehicles are taken into account. specifically, in this work, the network design problem aims to select the optimal planning policy from a set of infrastructure design scenarios considering both road expansions and charging station allocations under a specified construction budget. The user-equilibrium mixed-vehicular traffic assignment problem with en-route recharge （MVTAP-ER） is formulated into a novel convex optimization model and extended to a newly developed bi-level program of the aggregated NDP integrating recharge facility allocation （NDP-RFA）. In the algorithmic framework, a convex optimization technique and a tailored CA are adopted for, respectively, solving the subproblem MVTAP-ER and the primal problem NDP-RFA. systematic ex- periments are conducted to test the efficacy of the proposed approaches. The results highlight the impacts of distance limits and budget levels on the project selection and evaluation, and the benefits of considering both road improvement policy and recharge service provision as compared to accounting for the latter only. The results also report that the two design objectives, to respectively minimize the total system travel time and vehicle miles travelled, are conflicting for certain scenarios.

关键词： Aggregated network design problem mixed-vehicular traffic assignment recharge facilityallocation transport system optimization.

sYNTHEsIs,CHARACTERIZATION,THERMAl DEGRADATION AND ElECTRICAl CONDUCTIVITY OF OlIGO[2-(2-HYDROXYPHENYlIMINOMETHYlBENZYlIDENE)AMINOPHENOl]AND OlIGOMER-METAl COMPlEXEs

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Chinese Journal of Polymer science 2008年第2期26卷 131-143页

作者： Ismet Kaya süleyman Çulhaoglu Department of Chemistry Faculty of science and Arts Çanakkale Onsekiz Mart University TR 17020 Çanakkale Turkey

The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between 50-90℃.The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were *** the optimum reaction conditions,yield of the products were found to be 67.72% and 61.49% for air O_2 and NaOCl oxidants *** structures of the monomer ...

关键词： Air oxygen NaOCl Oligo[2-(2-hydroxyphenyliminomethylbenzylidene)aminophenol] Oxidative polycondensation Themal analysis Electrical conductivity Antibacterial activities.

Optimization of wear parameters of binary Al-25Zn and Al-3Cu alloys using design of experiments

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1465-1472页

作者： sreejith J s.Ilangovan Department of Mechanical Engineering Amrita School of Engineering

Zinc-aluminum alloys have been used as bearing materials in the past. In recent years, binary Al-Zn alloys and Al-Zn-Cu alloys are being used as an alternative to the Zn-Al alloys for bearing applications. In this study, both binary Al-25 Zn and Al-3 Cu were prepared using stir casting process. Homogenization of the as-cast alloys was performed at 350oC for 8 h and then, the alloys were furnace-cooled to 50oC. The homogenization led to the removal of the dendritic structure of the as-cast alloys. After homogenization, wear parameters optimization was carried out using Taguchi technique. For this purpose, l9 orthogonal array was selected, and the control parameters selected are load, velocity, and sliding distance. The optimum parametric condition was obtained using signal-to-noise(s/N) ratio analysis, and specific wear rate(sWR) is the selected response. The "smaller-the-better" is the goal of the experiment for s/N ratio analysis. After the optimization, confirmation tests were carried out using analysis of variance(ANOVA) from the developed regression equation. Finally, wear mechanism studies were conducted using scanning electron microscopy(sEM) and energy-dispersive X-ray spectroscopy(EDX) images.

关键词： specific wear rate micro-hardness Taguchi technique signal-to-noise ratio analysis of variance aluminum-zinc alloy aluminum-copper alloy

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肝硬化合并新型冠状病毒感染的研究进展

中国感染与化疗杂志 2024年第4期24卷 476-483页

作者：王雅婷张策吕梦瑶申川赵彩彦河北医科大学第三临床医学院石家庄050051 河北医科大学第二医院消化内科河北医科大学第三医院感染科河北省感染性疾病临床医学研究中心河北省重大传染病诊治与应急防控重点实验室

由新型冠状病毒(新冠病毒)引发的新冠病毒感染(COVID-19)至今仍呈全球流行,虽然其对人类的威胁在逐渐减弱,但老年人、免疫功能缺陷人群以及伴有严重基础疾病患者的重症率、病死率仍高于一般人群。肝硬化是一种进展期慢性肝病,全球共有1... 详细信息

由新型冠状病毒(新冠病毒)引发的新冠病毒感染(COVID-19)至今仍呈全球流行,虽然其对人类的威胁在逐渐减弱,但老年人、免疫功能缺陷人群以及伴有严重基础疾病患者的重症率、病死率仍高于一般人群。肝硬化是一种进展期慢性肝病,全球共有1.12亿例患者,每年约200万例死于失代偿并发症及肝细胞癌[1],造成了沉重的健康和经济负担。肝硬化患者因存在免疫功能障碍,感染新冠病毒后将加快患者肝硬化病程,促进急性失代偿事件的发生[2]。尽管对COVID-19的认识不断增加,但有关肝硬化合并COVID-19这一特殊人群的具体管理流程仍在不断探索和优化中。因此,本文就肝硬化患者合并COVID-19的流行病学、发病机制、高危因素及预后评估、临床特点、治疗及疫苗预防的进展展开综述。

关键词：肝硬化新型冠状病毒感染治疗

Tourism versus nature conservation: reconciliation of common interests and objectives——an analysis through Picos de Europa National Park

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Journal of Mountain science 2018年第11期15卷 2505-2516页

作者： lóPEZ Iván PARDO Mercedes Department of Psychology and sociology University of Zaragoza Department of social Analysis University Carlos Ⅲ of Madrid

Nature tourism and particularly tourism in national parks have acquired significant importance in contemporary societies. Post-Fordist consumers have reevaluated the meanings of ‘nature' and ‘natural spaces' and now avoid standardization to seek singularity. Tourism in national parks is a consequence of this tendency and has both positive and negative aspects. The purpose of this sociological research is to describe the most relevant conflicts in the Picos de Europa National Park(spain) involving the park's conservation, local economic development,and tourism. seven in-depth interviews and three focus groups were addressed to key local *** this research were identified three chief areas of existing or potential inter-related conflicts and the main actors interacting with them. The first is on population, particularly, the negative consequences of depopulations on the local socio-economic development and the environment. A second source of conflicts identified is caused by the difficult conciliation between commercial exploitation and conservation of the protected natural area. More precisely, this specific form of tourism positively contributes to the economy of local communities whilst problems can arise for the conservation goals of National Parks. Thirdly, in this research is also analyzed the institutional governance and the inter and intra-governmental conflicts as well as with the Park's management body. These findings provide important information for the improved management of tourism and conflicting interests in natural parks.

关键词： National parks Environmental conservation Nature tourism Mountain traditional economy Picos de Europa spain

Ca2+ signaling during vertebrate somitogenesis

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Acta Pharmacologica sinica 2006年第7期27卷 781-790页

作者： sarah E WEBB Andrew l MIllER Department of Biology the Hong Kong University of Science and TechnologyClear Water BayHong Kong SARChina

A variety of Ca2+signals,in the form of intercellular pulses and waves,have beenreported to be associated with the various sequential stages of somitogenesis:from convergent extension and the formation of the paraxial mesoderm;during thepatterning of the paraxial mesoderm to establish segmental units;throughout theformation of the morphological boundaries that delineate the segmental units,andfinally from within the maturing somites as they undergo subsequent develop-ment and *** to both the technical challenges presented in imag-ing intact,developing embryos,and the subtle nature of the Ca2+transientsgenerated,they have proved to be difficult to ***,a combinationof cultured cell preparations and improvements in explant and whole embryo im-aging techniques has begun to reveal a new and exciting class of developmentalCa2+*** this chapter,we review the small,but expanding,number ofreports in the literature and attempt to identify common characteristics of thesomitogenic Ca2+transients,such as their mode of generation,as well as theirspatial and temporal *** may help to elucidate the significance andfunction of these intriguing Ca2+transients and thus integrate them into the com-plex signaling networks that orchestrate early developmental events.

关键词： Ca2+ signaling somitogenesis zebrafish Xenopus mouse chick

Aircraft Measurements of Cloud–Aerosol Interaction over East Inner Mongolia

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Advances in Atmospheric sciences 2017年第8期34卷 983-992页

作者： Yuhuan lü Hengchi lEI Jiefan YANG Wuqing Meteorological Observatory ofTianjin Tianjin 301700 China Key laboratory of Cloud-Precipitation Physics and severe storm Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China

To investigate the potential effects of aerosols on the microphysical properties of warm clouds, airborne observational data collected from 2009 to 2011 in Tongliao, Inner Mongolia, China, were statistically analyzed in this study. The results demonstrated that the vertical distribution of the aerosol number concentration（N_a） was similar to that of the clean rural continent. The average aerosol effective diameter（D_e） was maintained at approximately 0.4 μm at all levels. The data obtained during cloud penetrations showed that there was a progressive increase in the cloud droplet concentration（N_c） and liquid water content（lWC） from outside to inside the clouds, while the Nawas negatively related to the Ncand lWC at the same height. The fluctuation of the N_a, Ncand lWC during cloud penetration was more obvious under polluted conditions（Type 1） than under clean conditions（Type 2）. Moreover, the wet scavenging of cloud droplets had a significant impact on the accumulation mode of aerosols, especially on particles with diameters less than 0.4 μm. The minimum wet scavenging coefficient within the cloud was close to 0.02 under Type 1 conditions, while it increased to 0.1 under Type 2 conditions,which proved that the cloud wet scavenging effect under Type 1 conditions was stronger than that under Type 2 ***, cloud droplet spectra under Type 1 conditions were narrower, and their horizontal distributions were more homogeneous than those under Type 2 conditions.

关键词： aircraft observation aerosol warm cloud microphysical properties

星源照射多基地雷达系统目标定位建模及精度分析

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现代雷达 2024年第4期46卷 22-33页

作者：董晴刘杰毛永飞吕争李晓蕊中国空间技术研究院遥感卫星总体部北京100094

星源照射多基地雷达系统由一个星载发射源与多个接收站组成,这种一发多收的雷达系统定位精度较单星定位精度高。因为工作体制和构型原因,一发多收雷达系统的定位精度受多种因素影响。为理清多基地雷达系统定位精度的影响因素,文中给出... 详细信息

星源照射多基地雷达系统由一个星载发射源与多个接收站组成,这种一发多收的雷达系统定位精度较单星定位精度高。因为工作体制和构型原因,一发多收雷达系统的定位精度受多种因素影响。为理清多基地雷达系统定位精度的影响因素,文中给出一种典型的一发多收雷达系统定位模型;其次,从几何稀释因子(GDOP)角度出发,对比不同接收站数量对定位精度的影响,发现雷达系统接收站数量为三收或四收时系统效费比较高;然后,研究了不同探测构型所对应的一发三收雷达系统定位精度,发现顶角为120°的Y形布局方式下系统定位精度最优;最后,给出了系统定位精度随目标高度的变化。

关键词：星源照射多基地雷达定位精度接收站数量布局方式