北京市农业保险发展模式的改进

为了完善北京市政策性农业保险制度,在北京市政策性农业再保险方式模拟研究的基础上,依据可持续发展要求,对“北京模式”进行改进,设计了由原保险公司购买再保险,并由政府予以扶持的“小改进”方案和实行三级巨灾风险保障的“北京新模式”。动态模拟结果表明,与政府购买再保险方式和“小改进”方案相比较,“北京新模式”既能实现保险公司持续经营,又有利于提高政府资金运作效率,是一种较优的政策性农业保险发展模式。     

Spatial cognition mechanism of health: The relationship between perceived accessibility of medical facilities and health and health behaviour

There is no consistent conclusion on the impact of improving the physical accessibility of medical facilities/resources on the utilisation of medical facilities and health outcomes, which may be due to neglecting the role of spatial cognition of physical facilities, which will be directly related to health behaviour and outcomes. This article uses China Migrants Dynamic Survey to examine the relationship between perceived accessibility of medical facilities and health and health behaviour. The results show that perceived accessibility is positively associated with health and related behaviour. The higher the perceived accessibility to the medical facilities, the better the subjective and objective health status of migrant residents. Similarly, the more positive the preventive and healthcare-seeking behaviour is. This study suggests that public policymakers need to intervene in residents' spatial cognition of medical resources around their neighbourhoods to enhance the collective benefits of medical facilities.     

阴雨寡照灾害对云南烤烟的种植风险预测

阴雨寡照灾害在未来将具有"空间+时间动态性"的变化特征.笔者根据烤烟种植适宜性指标和阴雨寡照等级指标,利用1981-2010年连续30年的逐日气象观测资料和2021-2050年全球气候模式HadGEM2-ES的RCPs排放情景预估结果,结合灾害系统理论,采用多元回归、"距平逼近"插值和栅格运算等方法,分析阴雨寡照灾害对...     

全球金融危机中的我国金融业及农业风险分析*

摘要：产业结构的变动是国民经济发展的重要特征,投入产出模型是检验经济中各产业的相互联系,进而分析一个国家或地区的宏观经济运行情况的一种经济数量分析方法。面对全球金融危机,本文运用投入产出表对金融产业与其他产业结构进行关联分析是深刻揭示金融产业结构内在机理的重要方法。本文选用了中间投入率、影响力系数、感应力系数三个指标来分析在全球金融危机中,北京、上海金融业的发展问题。研究发现,金融危机对于中国经济产业的直接冲击不会太大,但是对北京、上海的冲击可能是相对严重的。当前需要注意截断房地产开发业金融业的强烈作用,同时维护农业的发展。关键词：金融危机,投入产出;中间投入率,中国;北京;上海     

贵州省辣椒渍涝气象指数保险研究及应用

为促进贵州辣椒渍涝灾害气象指数保险业务的开展,降低农户受渍涝导致的经济损失风险,根据笔者制定出的渍涝等级标准处理贵州省84个国家气象站30年间降水量数据,得出各站点各级渍涝灾害频率,以及各站点的纯保险费率。利用克里金差值绘制出各级渍涝灾害频率分布图以及纯保险费率分布图,可以明显看出受渍涝灾害影响较大的辣椒种植地区主要集中于西南部以及南部部分区域;受渍涝灾害影响较小的辣椒种植地区主要在贵州西部、北部以及东部部分区域。纯保险费率较高的地区主要在贵州西南部以及东南部分地区,当免赔额不同时纯保险费率会有较大差距。辣椒渍涝气象指数保险在贵州有着较好的发展前景,不仅可以降低农户受渍涝灾害损失的风险,还能促进贵州辣椒产业持续稳定增长。     

农田土壤中氮的环境指标研究

氮肥的大量不合理施用使农田氮素成了农业面源污染的重要因子,然而关于农田氮素对环境污染的标准并没有系统的介绍。笔者分别从农田土壤氮素盈余、农田径流总氮、铵态氮、硝态氮等方面着手,介绍农田土壤中氮对环境产生的影响。土壤中氮素富集会加大农田土壤氮流失至水体的风险和数量。农田生态系统中氮素通过氨挥发、地表径流、下渗淋失等进入到环境,其盈余主要以气态、可溶态等形态对环境造成污染。综述国内外相关研究得到:农田径流损失的氮以可溶态为主,其中水稻田面水氮浓度超过30 mg/L会促使土壤矿质态氮部分释放,增加土壤溶液中矿质态氮含量,增加农田土壤氮流失风险;土壤无机N含量达到60 mg/kg时能满足作物的正常生长,超过此值,N素流失风险增加,多余的土壤NO3-N将会引起较大的环境风险。化肥使用量控制在150~180 kg/(hm~2·a)之内,可以有效控制化肥氮的损失污染。土壤氮素盈余、农田径流总氮、铵态氮、硝态氮等可作为农田土壤中氮的环境指标。     

Analysis of project financing risk distribution Based on Investor

By analyzing the kinds of risk and participants in project financing in ject financing risk distribution through the game theory analysis is studied. The this paper, the optimal principle of proauthors use the fuzzy analytic hierarchy process to establish the participants risk matrix, then, solve the matrix through Hungarian Algorithm according to the principle of risk effective distribution. After optimization,the best one who should undertake the risk will be decided.     

磁场处理对油菜种子生长发育影响的研究

研究了不同强度的磁场处理对油菜种子发芽率、发芽势的影响。结果表明,磁场为0～795 mT处理油菜种子,将会增大种子的发芽势和发芽率;在620～795 mT对油菜种子的发芽势和发芽率有最佳的促进效果。当磁场强度超过795 mT时,会对种子的发芽势和发芽率产生抑制作用。     

What drives university students to practice social distancing? Evidence from South Korea and Vietnam

As COVID-19 has caused unprecedented social change, governments are implementing several social measures to control transmission. Among them, social distancing is being enforced in almost all countries and is effective in preventing infection. Based on the importance of social distancing, this study identifies factors influencing the intention towards social distancing. The research model was developed by introducing risk perception in the theory of planned behaviour. To examine the proposed model, a survey was conducted with 339 university students from two countries, South Korea and Vietnam. The data were analysed using the partial least squares method. The results show that social distancing attitude and perceived behavioural control significantly influence social distancing intention. The findings indicate that both affective risk perception and cognitive risk perception serve as imperative factors in the formation of social distancing attitudes, subjective norms and perceived behavioural control. However, subjective norms and nationality do not affect social distancing intention. Based on the results, suggestions are made for policymakers to establish effective social measures.     

农业产业化经营中对农业保险的需求分析

农业产业化经营是社会主义新农村建设的有效途径,也是解决"三农"问题的重要组织形式,但农业产业化经营中面临着市场风险、技术风险与自然风险等一系列风险,使农业产业化进程中的不确定性大大增加,因此用建立配套的农业保险机制来规避风险,将对整个农业和农村的持续发展起到积极作用。     

啤酒酵母中乙醇脱氢酶基因Ⅰ的扩增与表达

乙醛是导致啤酒风味丧失的物质。当乙醛的含量超过15mg/L时,啤酒就会产生腐烂的青草味,影响口感。为了解决啤酒酵母菌株乙醛产量过高的问题,本研究拟在啤酒酵母中增加乙醇脱氢酶I(alcoholdehydrogenasⅠe,ADHⅠ)的拷贝数及其相应的表达量,使更多乙醛转变成为乙醇,从而达到改善啤酒风味的目的。     

The release of transgenic plants from containment, and the move towards their widespread use in agriculture

Summary The use of transgenic plants in breeding makes it possible to utilise a wide variety of novel genes from unrelated plants, microbes and animals. Because of the diversity of genes that have now become available for modifying crop plants, it is agreed internationally that there should be a risk assessment before transgenic plants are grown outside the laboratory or glasshouse. Various aspects are considered in a risk assessment including any non-target effects of the transgene, changes in plant persistence and invasiveness, and the possibility of movement of the transgenes to wild populations by cross pollination. It is generally argued that the need for risk assessment and regulation should be determined by an analysis of certain products of transformation, rather than a risk assessment being required for all plants modified by the process of transformation. A possible consequence of considering the product only, however, could be that some of the products of conventional breeding may need to be assessed by the risk assessment procedures developed for transgenic plants. There are discussions with interest groups on the use of transgenic plants in the environment and in food products. It is likely that some form of labelling will be required for certain foods containing ethically-sensitive genes. There is little doubt that transgenic plants will make a significant contribution to agriculture in the coming decades. Developments in the patenting of genes, release regulations, food labelling, consumer reaction etc., will influence the rate of progress and should be considered in the strategic planning of plant breeding programmes.     

Study on Influence of the Requirement on the Capital Adequacy to Bank''s Yields

In this paper, the model of the maximum utility of profit margin of commercial banks under the credit risk and the interest risk is reformulated with full consideration of the profile of the losses of bad debts for the commercial banks. The influence of the requirement in the capital adequacy by the central bank to the commercial banks on bank's yields is studied.Analysis shows that considering the risk loss and risk cost of the commercial bank,enhancing the capital adequacy to commercial bank will increase margin profit of commercial bank with decreasing absolute risk avoidance under the Ross concep.     

新收获小麦生芽粒及其对降落数值的影响

小麦生芽粒包括萌动粒及较为严重的发芽小麦,当生芽率大于10％时,对小麦的工艺品质、储藏品质、加工品质都会造成影响.生芽后,会产生大量的α—淀粉酶,而降落数值能反映α-淀粉酶活性及小麦发芽损坏程度.通过选取陕西地区2013年新收获小麦并检测其生芽率和降落数值,发现降落数值低于150 s的占37.5％,在200 s～300 s之间的占62.5％,而且随着生芽率的增加,降落数值呈下降趋势,此试验对加强储藏条件的选择和控制,减少储藏期间的损失提供参考.     

Cause and Consequence in Maize Planting Dates in Germany

An important part of agricultural adaptation is the timing of crop sowing dates, affecting yields and the level of risk incurred during a particular season. Cold stress is especially relevant in maize, Zea mays L., so that the timing of planting in the spring is a tactical response to short‐term weather, but is also subject to strategic planning with regard to longer‐term climate. Both factors compare the potential implications of cold stress to the additional yield obtainable through earlier planting. New cultivars suited to growing conditions in Europe and generally increasing spring temperatures have enabled earlier planting, but it is still dependent on short‐term weather during the planting period. In the context of field‐level decision‐making, a panel regression is used to estimate the relationship between weekly local temperature and precipitation and planting dates at specific sites throughout Germany. Next, localised weather data and planting behaviour are linked to yields at the district (Landkreis) level to show the effects of planting date on yield. Based on these relationships optimal planting dates are explored with some associated costs and benefits. Results show a trend towards earlier planting that follows observed increasing spring temperatures and the availability of more cold‐tolerant cultivars but this advance is buffered by the increasing severity of minimum temperatures during a critical period. Earlier planting potentially increases yield but this is offset by additional management costs and risk. A robust and simple depiction of farmer behaviour in climatic, technological and economic context can help to understand trends in crop management and productivity that effect agricultural landscapes.     

绿茶酸牛乳保藏过程中品质变化研究

对绿茶酸牛乳保藏过程中的品质变化进行研究。绿茶酸牛乳在4℃冷藏条件下,其功能性成分叶绿素、茶多酚、游离氨基酸的含量逐渐减少;在保存6 d时,挥发性风味物质以芳香阈值较高的醛类、酸类等为主。确定绿茶酸牛乳的最佳饮用时间为4℃冷藏条件下保存5～6 d,超过此期限,绿茶酸牛乳的营养价值下降。     

平房仓真空抽取诱捕器测虫试验

在储粮最易受害虫感染的夏季,在仓内设置真空抽取(负压吸出)诱捕器,将落入陷阱诱捕器的储粮害虫通过管道由仓外负压吸出,可以快速地检测害虫种类及密度,既能提前发现储粮害虫,又减少了进仓感染害虫的几率,为储备粮安全储存奠定了基础。     

Selection for fast germination in rapeseed (Brassica napus L. and B. Campestris L.)

Summary Eleven populations of Brassica napus L. and twelve populations of B. campestris L. were subjected to three cycles of selection for fast germination at 2°C and at 25°C. The seeds from the selected populations, and unselected control populations grown in the same environment as the selected populations, were examined for germination behaviour at 2°C and 25°C, and for growth behaviour at 10°C. The populations in both species responded differently in terms of germination behaviour to selection for fast germination. In most of the populations that did respond positively to selection, selection practised at 2°C was superior to selection at 25°C in improving percent germination at 2°C, and was as good as the selection at 25°C in improving germination rate at the higher temperature. Selection for fast germination had no effect on growth characteristics of B. napus and B. campestris populations grown at 10°C. Thus, selection for fast germination at one low temperature may lead to improvement in germination characteristics over a range of temperatures, but will not necessarily lead to improved growth performance of the selected populations.     

Crossability between tritordeum and triticale

Seed set over three years in crosses between three tritordeums used as female parents and four triticale lines, showed that there are significant differences in crossability attributable to both parents and that most of these differences are consistent over the three years. When used as the female parent tritordeum line HT67 had an average seed set of 29.62%, tritordeum line HT9 an average of 12.73%, and tritordeum line HT31 an average of only 6.58% averaged over the four triticales lines used as pollinators. These data show genotype effect that is highly significant (P < 0.001) both for tritordeum and triticale genotypes and highly significant (P < 0.001) female ×year, male × year and female × pollinator interactions. The behaviour of F₁ tritordeum hybrids when crossed with one of the triticale pollinators supports the conclusion that the parents' crossability behaviour is genetically controlled. Analysis of segregation ratio of F₂ hybrids plants from high and low crossability tritordeum genotypes crossed with the same triticale pollinator genotype is consistent with 9:3:3:1 ratio. This revised version was published online in August 2006 with corrections to the Cover Date.     

风险分析在农产品质量安全管理中的应用

通过对风险分析的发展历程、基本内涵、特征以及国际组织和国内开展农产品质量安全风险分析的情况研究,认识了风险分析在农产品质量安全管理中的应用。结果表明：风险分析在WTO工作中的作用至关重要。它是制定农产品安全标准和解决国际农产品贸易争端的依据。风险分析将成为制定农产品安全政策,解决一切农产品安全事件的宏观管理模式。在认识到中国开展农产品质量安全风险分析的重要性基础上,提出了建立中国农产品质量安全风险分析制度的建议。