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Sexual Dimorphism of the Jilin Clawed Salamander,Onychodactylus zhangyapingi,(Urodela:Hynobiidae:Onychodactylinae) from Jilin Province,China 被引量:2
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作者 Jianli XIONG Xiuying liU +2 位作者 Xiaomei ZHANG mengyun li Yao MIN 《Asian Herpetological Research》 SCIE CSCD 2016年第3期220-226,共7页
Sexual dimorphism in size and shape is common in many organisms, and is a key evolutionary feature. In this study, we analyzed morphometric data of the Jilin clawed salamander Onychodactylus zhangyapingi, an endemic C... Sexual dimorphism in size and shape is common in many organisms, and is a key evolutionary feature. In this study, we analyzed morphometric data of the Jilin clawed salamander Onychodactylus zhangyapingi, an endemic Chinese salamander, to examine sexual size and shape dimorphism. The morphometric data included 14 characteristics of 13 females and 11 males and was analyzed using univariate and multivariate methods. Our results showed that sexual dimorphism occurs not only in body size, but also in body shape. Males have a longer snout-vent length than females, a rarely reported pattern of male-biased sexual size dimorphism. Females have a larger space between the axilla and groin than males, while males have longer and larger tails compared to females. The sexual dimorphism in body size and shape can be explained by existing theories, but there is little data for the mating system, behavior, reproduction, or ecology of O. zhangyapingi, so further studies are required. 展开更多
关键词 sexual mating evolutionary Jilin endemic reproduction longer univariate multivariate explained
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城市创业对经济增长的影响探究 被引量:6
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作者 李梦云 廖理 王正位 《经济学报》 CSSCI 2021年第1期1-28,共28页
经济增长的关键驱动因素一直受到学术界和政策界的广泛关注。近年来,我国出台了一系列创业激励政策希望推动经济增长。因此,本文聚焦于创业与经济增长这两个重要议题,实证分析城市创业水平对经济增长的影响。本文利用国内市级行政单位... 经济增长的关键驱动因素一直受到学术界和政策界的广泛关注。近年来,我国出台了一系列创业激励政策希望推动经济增长。因此,本文聚焦于创业与经济增长这两个重要议题,实证分析城市创业水平对经济增长的影响。本文利用国内市级行政单位每年的创业数据及经济增长数据,选取实缴制改为认缴制政策作为外生冲击,运用双重差分方法证明了创业水平对经济增长的驱动作用。随后,通过双重差分分阶段检验比较了创业对经济增长影响的时间变化规律,并进行了渠道检验和一系列稳健性检验。本文的工作补充了创业与经济增长的相关研究,同时也能够为相关政策制定提供指导意见。 展开更多
关键词 创业 经济增长 认缴制政策
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Morphological Characteristics of the Dorsal Skin of Two Hynobiids and Their Adaptive Role in Aquatic and Terrestrial Habitats 被引量:1
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作者 Jianli XIONG Chongshan DAI +2 位作者 mengyun li Wen DENG Jichang li 《Asian Herpetological Research》 SCIE 2013年第1期62-67,共6页
The morphological characteristics of the dorsal skin of trunk in two species of hynobiid salamanders, Batrachuperus pinchonii and Hynobius chinensis were examined by light microscopy. The basic structures of the skin ... The morphological characteristics of the dorsal skin of trunk in two species of hynobiid salamanders, Batrachuperus pinchonii and Hynobius chinensis were examined by light microscopy. The basic structures of the skin in the two species are similar and consist of two layers: epidermis and dermis. The epidermis consists of stratum corneum, stratum intermedium and stratum germinativum, while the dermis is composed of a stratum spongiosum and stratum compactum. However, some species-specific variation has been identified (e.g., the distribution of capillary vessels and gland cells, and the thickness of skin). H. chinensis is a terrestrial species and only lives in water during breeding period, but B. pinchonii is aquatic and remains aquatic throughout its lifetime. The differences in the distribution of capillary vessels and gland cells are related to their different habitats, and show a morphological adaptation. 展开更多
关键词 hynobiid salamander SKIN morphology ADAPTATION HABITAT
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Impacts of strong El Ninon summertime near-surface ozone over China 被引量:1
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作者 mengyun li Yang Yang +2 位作者 Pinya Wang Dongsheng Ji Hong liao 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第4期13-18,共6页
利用全球大气化学三维模式(GEOS-Chem)模拟研究两次强厄尔尼诺事件(1997/98和2015/16)对中国夏季近地面臭氧(O_(3))浓度的影响.结果表明1997/98年厄尔尼诺事件发展期夏季中国东北区域O_(3)浓度升高,最大值超过6ppb,这主要归因于高温晴... 利用全球大气化学三维模式(GEOS-Chem)模拟研究两次强厄尔尼诺事件(1997/98和2015/16)对中国夏季近地面臭氧(O_(3))浓度的影响.结果表明1997/98年厄尔尼诺事件发展期夏季中国东北区域O_(3)浓度升高,最大值超过6ppb,这主要归因于高温晴朗低湿等气象因素导致O_(3)化学生成升高.此外,两次厄尔尼诺事件发展期夏季O_(3)浓度在中国南部均增加了3ppb,这与盛行季风减弱导致中国南方O_(3)局地积累有关.相反,在两次强厄尔尼诺衰减期夏季,中国大部分地区O_(3)浓度下降伴随着海温模态转变为拉尼娜事件.这表明厄尔尼诺在调节中国近地面O_(3)浓度中发挥着重要作用. 展开更多
关键词 厄尔尼诺 臭氧 GEOS-CHEM
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Energy-aware fuzzy job-shop scheduling for engine remanufacturing at the multi-machine level
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作者 Jiali ZHAO Shitong PENG +3 位作者 Tao li Shengping LV mengyun li Hongchao ZHANG 《Frontiers of Mechanical Engineering》 SCIE CSCD 2019年第4期474-488,共15页
The rise of the engine remanufacturing industry has resulted in increased possibilities of energy conservation during the remanufacturing process,and scheduling could exert significant effects on the energy performanc... The rise of the engine remanufacturing industry has resulted in increased possibilities of energy conservation during the remanufacturing process,and scheduling could exert significant effects on the energy performance of manufacturing systems.However,only a few studies have specifically addressed energy-efficient scheduling for remanufacturing.Considering the uncertain processing time and routes and the operation characteristics of remanufacturing,we used the crankshaft as an illustrative case and built a fuzzy job-shop scheduling model to minimize the energy consumption during remanufacturing.An improved adaptive genetic algorithm was developed by using the hormone modulation mechanism to deal with the scheduling problem that simultaneously involves parallel machines,batch machines,and uncertain processing routes and time.The algorithm demonstrated superior performance in terms of optimal value,run time,and convergent generation in comparison with other algorithms.Computational results indicated that the optimal scheduling scheme is expected to generate 1.7 kW∙h of energy saving for the investigated problem size.In addition,the scheme could improve the energy efficiency of the crankshaft remanufacturing process by approximately 5%.This study provides a basis for production managers to improve the sustainability of remanufacturing through energy-aware scheduling. 展开更多
关键词 remanufacturing scheduling adaptive genetic algorithm energy efficiency sustainable remanufacturing hormone modulation mechanism
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