Weiwoboidae fam.nov.of 'Higher' Fulgoroidea (Hemiptera:Fulgoromorpha) from the Eocene Deposits of Yunnan,China     

Lin Qibin  Jacek Szwedo  Huang Diying  Adam Stroiński 《《地质学报》英文版》2010,84(4):751-755

<正>A new family of so-called‘higher' planthoppers,Weiwoboidae fam.nov.,from the Lower Eocene of Yunnan is described.A new monotypic genus,Weiwoboa gen.nov.,with Weiwoboa meridiana sp.nov.is also described and illustrated.The characters of tegmen venation of the new family,its evolution,and supposed relationships are briefly discussed.  相似文献   

一个新的正规定则     

王柳  张庆德 《成都信息工程学院学报》2006,21(Z1):98-103

证明了单位圆内亚纯函数族F,若不正规,则存在一个函数列在开平面上的任意紧子集上一致收敛于一个非常数的亚纯函数,并应用它得到一个新的正规定则:设F为区域D内的一亚纯函数族,若对每一f∈F,fnf′≠1(n≥2),则F在区域D内正规.  相似文献   

凡纳滨对虾家系淡水耐受性状与生长性状的关系   总被引：2，自引：0，他引：2       下载免费PDF全文

杨海朋  胡超群  张吕平  任春华  王艳红 《热带海洋学报》2014,33(4):69-76

本研究对亲本来自不同遗传背景的10个凡纳滨对虾家系进行了淡水应激试验和淡化培育试验,分别测定了其淡水应激存活率和淡化培育过程中的各项生长性状指标,并研究了凡纳滨对虾家系淡水耐受性与其淡化培育过程中生长性状的关系。结果显示:1)10个凡纳滨对虾家系淡水应激存活率存在极显著差异(p0.01),由高到低为TF-1(68%)DG-1(58%)HX-2(56%)SD-1(50.5%)TF-2(38%)=DG-2(38%)DF-1(35%)SD-2(34%)DF-2(33%)HX-1(27%);2)淡化培育过程中,10个凡纳滨对虾家系之间的淡化培育存活率由高到低为TF-1(51%)SD-1(44%)DG-1(40%)TF-2(36%)HX-2(29%)SD-2(25%)DG-2(20%)DF-2(17%)DF-1(16%)HX-1(13%),存在极显著差异(p0.01),体重增长率、特定生长率和体长增长率10个家系之间存在显著性差异(p0.05),而且不同家系的饵料系数之间也存在显著性差异(p0.05);3)获得的家系TF-1的淡水应激存活率(68%)、淡化培育存活率(51%)、体重增长率(17.54mg·d–1)、特定生长率(6.68)和体长增长率(0.53mm·d–1)都高于其他家系,饵料系数(0.82)与其他家系相比则最低;4)淡水应激存活率与淡化培育存活率及体长增长率存在极显著的相关性(r0.8,p0.01),与平均增重率、特定生长率、饵料系数存在一定的相关性(0.5|r|0.8,p0.05)。研究表明:凡纳滨对虾仔虾的淡水应激存活率反映了虾苗的耐淡能力,可作为选择淡化培育用虾苗的一个重要指标;家系TF-1为进一步选育出耐淡能力更强和生长更快的新品系提供了基础。  相似文献   

Effect of culture methods on individual variation in the growth of sea cucumber Apostichopus japonicus within a cohort and family     

邱天龙  张立斌  张涛  柏雨岑  杨红生 《中国海洋湖沼学报》2014,32(4):737-742

There is substantial individual variation in the growth rates of sea cucumber Apostiehopus japonicus individuals. This necessitates additional work to grade the seed stock and lengthens the production period. We evaluated the influence of three culture methods （free-mixed, isolated-mixed, isolated-alone） on individual variation in growth and assessed the relationship between feeding, energy conversion efficiency, and individual growth variation in individually cultured sea cucumbers. Of the different culture methods, animals grew best when reared in the isolated-mixed treatment （i.e., size classes were held separately）, though there was no difference in individual variation in growth between rearing treatment groups. The individual variation in growth was primarily attributed to genetic factors. The difference in food conversion efficiency caused by genetic differences among individuals was thought to be the origin of the variance. The level of individual growth variation may be altered by interactions among individuals and environmental heterogeneity. Our results suggest that, in addition to traditional seed grading, design of a new kind of substrate that changes the spatial distribution of sea cucumbers would effectively enhance growth and reduce individual variation in growth of sea cucumbers in culture.  相似文献   

Mapping family connectedness across space and time     

Caglar Koylu  Diansheng Guo  Alice Kasakoff  John W. Adams 《制图学和地理信息科学》2013,40(1):14-26

Understanding the structure and evolution of family networks embedded in space and time is crucial for various fields such as disaster evacuation planning and provision of care to the elderly. Computation and visualization can potentially play a key role in analyzing and understanding such networks. Graph visualization methods are effective in discovering network patterns; however, they have inadequate capability in discovering spatial and temporal patterns of connections in a network especially when the network exists and changes across space and time. We introduce a measure of family connectedness that summarizes the dynamic relationships in a family network by taking into account the distance (how far individuals live apart), time (the duration of individuals’ coexistence within a neighborhood), and the relationship (kinship or kin proximity) between each pair of individuals. By mapping the family connectedness over a series of time intervals, the method facilitates the discovery of hot spots (hubs) where family connectedness is strong and the changing patterns of such spots across space and time. We demonstrate our approach using a data set of nine families from the US North. Our results highlight that family connectedness reflects changing demographic processes such as migration and population growth.  相似文献   

Manoeuvring the middle ground: Social mobility and the renegotiation of gender and family obligations among Chinese Singaporeans     

Kristina Göransson 《Norsk geografisk tidsskrift. Norwegian journal of geography》2013,67(4):249-258

The article examines Singaporeans' experiences of upward social mobility and how traditional gender roles within the family are renegotiated and reinterpreted in Singapore. When the former British colony gained independence in 1965 its post-colonial government embarked on an ambitious modernization programme, under which villages were demolished and residents relocated to new high-rise estates, farmland gave way to factories, the education system was reformed, and women entered the workforce. The transformation has been accompanied by a rapid upward social mobility, whereby Singaporeans born in the midst of the transformation, in the period 1960s – 1980s, lived remarkably different lives compared with preceding generations. The article is an ethnographic analysis of how Singaporean middle-class women and men, who have experienced rapid upward social mobility, handle and negotiate changing expectations regarding gender and intergenerational support. The analytical framework is constructed around the concepts of social mobility, modernity, and spaces of contestation and negotiation. The ethnographic data illuminate how traditional family values, such as filial piety, are contested and renegotiated. The data also show how social mobility intersects with other forms of mobility, such as the spatial movement involved in urbanization. Women entering the labour force have to spend their days away from home and can no longer fully attend to their elderly family members and/or young children. However, spatial movement in the sense of increased access to transportation and communication has also enabled members of extended families to maintain their ‘urban kinship network’ without having to live together.  相似文献   

涉及一个微分多项式分担值的正规定则     

鲍文竹  张兆迎 《成都信息工程学院学报》2010,25(2):210-212

应用正规族理论及Zalcman引理,推广了Yuntong Li和Yongxing Gu一个亚纯函数正规性的定理,得到了下面的定理,即：设罗为复平面上一区域D上的亚纯函数族,k,n≥k＋2为正整数,a为非零有穷复数,L（f^n）的表达式为a0（f^n）^k）＋a1（f^n）^（k-1）＋…＋ak（fn）,其中a0≠0,a1,…,ak为复数,对任意的f,g∈F,L（fn）,L（gn）在D内分担a,则矿在D上正规．  相似文献   

Orbital properties of Jupiter-family comets     

Brian G. Marsden 《Planetary and Space Science》2009,57(10):1098-1105

The history of “comet families”, in particular the Jupiter comet family, is reviewed, together with ways in which the Jupiter family has been defined. New criteria are proposed, particularly with regard to distinguishing Jupiter-family comets (JFCs) from centaurs. The effect of nongravitational forces on JFCs is also discussed.  相似文献   

旅游商业化背景下家的空间重构 ——以西双版纳傣族园傣家乐为例   总被引：1，自引：0，他引：1  

郑诗琳  朱竑  唐雪琼 《热带地理》2016,36(2):225-236

旅游地的特色民居被改建为家庭旅馆,家的属性和内涵发生改变,影响着旅游地的文化生态。然而,当前研究仅将家庭旅馆视为“商业机构”,忽视了其具备的原本“家”的属性。家作为人文地理研究的新议题,受到了文化地理学的关注;但相比于国外丰富的家的地理学研究,国内的学术研究仍较为缺乏。以云南省西双版纳傣族园傣家乐为案例,通过观察法和访谈法,从“家”的视角出发解读作为“商业化的家”的傣家乐内部空间重构过程和动因,并关注其对空间内涵的影响。研究发现：家空间的重构是旅游活动主体之间互动协商的产物,游客对于家的消费和居民对于家的营造交织作用,共同推进了家空间的重构。傣族园傣家乐主人的家空间重构过程是从空间功能转化―空间扩增―空间异化―空间营销的渐变。游客是傣楼空间重构的主导力量,是家的空间消费主体,其凝视诉求和消费喜好直接推动了家的空间转变。傣家乐主人是家空间重构的建构主体,他们的文化背景和对家的舒适性诉求带来了家的空间属性多元化和复杂化的转变。家空间的变化不仅导致了傣家乐主人和游客在家空间的身份展演多元化和对空间认知多样化的变化,亦让家成为一个兼具有经济、文化消费、社会关系建立及多重身份展演的多元化、复杂化的社会空间。  相似文献   

Oil charge history of Paleogene–Eocene reservoir in the Termit Basin (Niger)     

J. Liu  G. Zhang  Z. Li  Y. Tang  H. Xiao  H. Lai 《Australian Journal of Earth Sciences》2019,66(4):597-606

A total of 73 oils from the sandstone reservoir of Paleocene–Eocene Sokor 1 Formation in the Termit Basin (eastern Niger) were analysed to investigate the distribution characteristics of biomarkers. Most of the oil samples are quite similar in their organic geochemical characteristics and should have been derived from the same source bed/source kitchen. The homogenisation temperatures of aqueous inclusions in Paleocene–Eocene reservoir of the Termit Basin vary with a range of 76–125?°C. By combining the homogenisation temperatures with the burial and geothermal histories reconstructed by 1-dimensional basin modelling, the timing and episode of oil charge can be obtained, i.e. 13 to 0?Ma for Paleocene–Eocene reservoirs in the Termit Basin. Two presentative geochemical parameters, i.e. Ts / (Ts?+?Tm) and 2,4-dibenzothiophene/1,4-dibenzothiophene (2,4-DMDBT/1,4-DMDBT) were applied to trace the oil migration direction and filling pathway. The preferred oil-filling points in the northwest section of the Termit Basin were determined, and the promising exploratory targets were proposed for further oil exploration in this region.  相似文献