Theoretical consideration of effect of fishing mortality on growth and reproduction of fish populations

Summary An increase in fish mortality due to fishing can theoretically change the growth and reproduction of fish populations from the viewpoint of adaptation. We address the issue of how an iteroparous fish should convert surplus energy into somatic growth and reproduction at each age under given conditions of mortality. A model of life history, which maximizes the net reproductive rate using the discrete maximum principle, is improved employing a new relationship between body weight and surplus energy which we have recently proposed. The model is applied to the North Sea plaicePleuronectes platessa, for which it has been reported that the average length of young fish had increased whereas that of old ones had decreased for some decades. Although the model cannot directly explain the former phenomenon, the two phenomena can be interpreted as a change in the optimal life history due mainly to an increase in mortality.     

重塑大学生就业观

随着我国高等教育事业的发展 ,高校的不断扩招 ,就业形势越来越严峻。“先就业 ,后择业 ,再创业”的择业观为各高校所倡行 ,但这种择业观中隐含了不少弊病。从目前我国高校就业形势来看我们认为应当从社会要求、诚信教育、职业理想及规划等方面对学生进行引导和教育 ,在此基础上秉承“先择业 ,后就业 ,再择岗”的择业观 ,才比较符合现实。     

武汉大学女性教职工婚姻生活调查分析

从武汉大学女教职工关于婚姻生活的满意度、夫妻关系、家庭地位以及家务劳动等方面可以窥见到目前我国高校女教职工婚姻生活质量。     

项目管理:基于生命周期和基于职能活动的管理

对应着项目的"一次性"和"多项活动复合性"的本质特征,项目管理有两种基本模式,即基于生命周期的项目管理和基于职能活动的项目管理,二者的内容体系不同,各有优劣,模式的选用要综合考虑项目的具体性质和企业的发展现状.     

从诗歌创作中看埃米莉·迪金森的智慧人生

沿着埃米莉·迪全森极具个人色彩的人生经历，简要分析了她三首短小却意义深远的诗歌。指出长年沉浸在孤独、沉思中的诗人，所写诗句不仅清新、优美，那些有血、有肉、有灵的篇章更凝结着诗人的心血，也折射出她一生的智慧和情感。诗人坚持用自己的艺术形式和审美标准创作的诗歌必将会深深影响和启迪着读者的心智．     

加强政府诚信建设的制度探讨

政府诚信是政府为政之本。政府诚信受观念、环境、制度、体制等诸多因素制约。从制度层面揭示政府诚信建设的制度需求、制度缺陷,会为政府相关制度的创新提供对策与思路。     

Person, Perception, and Place: What Matters to Health and Quality of Life

Interest in understanding how characteristics associated with where people live, in addition to the characteristics of the people themselves, affect health outcomes has risen sharply in recent years. While much of the research examining this question focus on teasing apart effects of place and individual on outcomes, less attention has been paid to examining how individuals’ perceptions of where they live may provide some clues to better understanding the influence of place on outcomes. We present findings from analysis undertaken that incorporate the subjective responses of individuals, residing in three socially contrasting neighbourhoods, to their local environment. Our first question addressed whether perceptions related to neighbourhood and city of residence matter to self rated health and quality of life independent of individual characteristics, while the second question examined whether the perceptions and individual characteristics are modified by the neighbourhood socio-economic context. Our results show that perceived neighbourhood characteristics, in addition to individual sociodemographic factors, are significant correlates of self rated health and quality of life. Moreover, we show that the type of perceived neighbourhood characteristics and the magnitude of their influence on self rated health and quality of life vary depending on whether they live in high- versus low-socioeconomic status neighbourhoods.

中国城市化发展对粮食生产影响分析

1990年之后,我国粮食生产变动较大,同时我国城市化的两个主要方面——人口城市化和土地利用城市化继续迅速发展,分别表现为:粮食总产量波动很大,人均粮食产量呈减少趋势;人口城市化保持快速推进,导致农业劳动力数量减少、素质弱化;土地利用的城市化发展速度更快,造成耕地面积减少、质量不断降低。数据分析显示,我国目前粮食生产仍主要依靠劳动力和耕地两大基本要素的投入,因此城市化的上述发展特征,将对中国粮食生产造成不利影响。     

胡仔生平新考

胡仔的《苕溪渔隐丛话》是宋代的一部重要诗话总集。该书的价值不仅体现在文献方面，其间也有胡仔自己精到的品诗论人之语，惜前人对此罕有论及。欲探求胡仔的诗学观点，必先对其本人做以清楚的了解。然《宋史》未为其立传，学界的间或之论亦凌乱和残缺。文章通过对相关资料进行整合，并利用新的文献资料，对胡仔的生平做了较为完整清晰的勾勒，从而为胡仔的诗学批评理论研究奠定基础。