北京市农产品加工企业效益的决定因素分析

本文利用抽样调查数据,借助多元回归模型对北京市农产品加工业经济效益和社会效益的决定因素进行了分析,回归结果表明:新增投资、技术人员比例、资源与能源的消耗等对企业的经济效益有显著的正影响;而企业产值、是否加入行业协会、是否与农户签订有购销合同、是否国家级龙头企业等因素会显著影响企业的社会效益;此外,行业类型、所有制形式、企业所处区域等对北京市农产品加工业的社会效益和经济效益都有重要影响.     

干旱胁迫下烟草脯氨酸杂种优势及相关基因差异表达分析

为探讨干旱胁迫下烟草脯氨酸杂种优势的分子遗传基础,以抗旱性差异较大的7个烟草品种及其组配的10个杂交组合为材料,采用盆栽试验设置干旱胁迫处理,进行了烟草脯氨酸杂种优势及其相关基因差异表达分析。结果表明,干旱胁迫下烟草脯氨酸含量在胁迫早期持续增加,第14天后开始下降;杂交组合间脯氨酸含量性状杂种优势差异明显,中亲优势最高40.35、最低-51.66;强优势组合中脯氨酸合成关键酶基因P5CS和δ-OAT相对表达量明显高于弱优势组合,分别是弱优势组合的2.10倍、1.87倍;脯氨酸杂种优势与P5CS基因相对表达量在旺长期持续干旱7 d时存在显著正相关关系,与δ-OAT基因相对表达量在伸根期持续干旱14 d、旺长期持续干旱7 d和14 d呈显著或极显著的相关关系,相关系数分别为0.93、0.98和-0.96。结果显示,脯氨酸合成关键酶基因δ-OAT和P5CS的时序性上调或下调表达是相应时期烟草脯氨酸含量性状杂种优势形成的分子基础。     

用Pearson-Ⅲ概率分布推算梅州春旱的重现期

用Pearson-Ⅲ型分布对梅州市春季（3—5月）的逐年降水量进行拟合,试图计算春季各月和整个春季降水总量在不同重现期下的极小值,从而得出它们在不同重现期下的干旱程度。结果表明：春季5年一遇的降水量极小值为371．45mm,10年一遇的降水量极小值为308．98mm,50年一遇的降水量极小值为217．74mm,100年一遇的降水量极小值为190．73mm。另外通过对春季不同降雨量的重现期计算,并与实况相验证,发现拟合结果是可信的。此外还计算了梅州市2002年春季干旱的重现期为：3月份约5．4年,4月份20．7年,5月份约40．7年,而整个春季干旱的重现期则为181年,表明2002年的春季干旱确实是近百年来少见的。     

改革开放30年农业院校食品安全的教学与科研发展状况

为了解中国改革开放30年,农业院校食品安全的教学与科研发展状况,介绍食品质量与安全专业的教学、科研和机构设置。食品质量与安全专业已经成为我国高等农业院校的特色专业,该专业成为培养食品质量与安全领域高素质人才的基地,成为食品质量与安全领域科技成果的主要产出单位。     

湘江近年枯季低水位的原因及解决对策

受气候变化和人类活动的影响,近年来湘江汛后连续出现干旱和超低水位,严重影响了长株潭城市群生产和生活用水安全。分析了超低水位出现的原因;根据地区供水、用水和节水潜力,提出了解决干旱缺水的工程和非工程措施。研究表明：流域降雨量少是湘江连续出现低水位最主要原因,人类活动影响是多方面的,通过采用综合措施,可以解决湘江枯季低水位及地区用水问题。     

基于特征空间的遥感干旱监测方法综述

遥感干旱监测是干旱监测中一个很有潜力的发展方向,其中研究比较多的是遥感特征空间法。为此介绍了几种具有代表性的遥感特征空间方法,并将其分为3大类,即LST NDVI特征空间法、NIR Red特征空间法和NIR SWIR特征空间法。深入地分析它们的基本原理、方法和适用范围,对各类干旱监测方法存在的问题和发展趋势进行了探讨,指出下一步的研究方向。     

Child bystanding: A risk factor for injury and identifying its’ determinants on midwestern agricultural operations

Background

Agriculture is considered among the most dangerous occupations and has consistently ranked among the top three. Production processes, associated with this occupation, place at risk not only workers but also others who live on the operations. We evaluated the incidence and determinants of associated bystander injuries in the Regional Rural Injury Study-II (RRIS-II).

Methods

The RRIS-II followed 32,601 people (∼85% of eligible) from rural communities in the Midwest for 1999 and 2001, using six-month recall periods, and identified their injury events. Demographic, injury, and exposure data were collected through comprehensive and case-control computer-assisted telephone interviews. Multivariate logistic regression analyses were used to estimate the risk of child bystanding and agricultural injury, while controlling for potentially confounding variables.

Results

Nearly 60% of all 425-child injury cases (<20 years) responded to sometimes/frequently bystanding in six out of seven different agricultural environments (e.g., workshops, animal areas, etc.) Multivariate regression analyses, with odds ratios and 95% confidence intervals, showed increased odds of injury for bystanding near used (1.5; 1.1, 1.9) or stored (1.4; 1.1, 1.8) machinery, and near fields and barnyards (1.4; 1.0, 1.9). Further, multivariate analyses revealed increased odds of bystanding for parental beliefs, such as: child age (1.4; 1.0, 2.0) near stored equipment. Parental levels of strictness were also evaluated and showed decreased odds of bystanding when the parents were not strict about the child's wearing a seatbelt near used equipment (0.5; 0.3, 1.0). Households with only one child had decreased odds of bystanding for five of the exposures while there was an increased odds of bystanding near animals for households with five or more children.

Conclusions

Although parents cannot child-proof their operations, it is important for them to understand the apparent odds of and risks associated with bystanding. Children can have injury odds similar to adults in this environment; therefore, it is necessary to examine parental factors that may be associated with children's likelihood of bystanding in high-risk work environments.     

关于农场农机网络信息管理系统

黑龙江八一农垦大学精准农业技术研究中心根据友谊农场农机管理现代化的需求,进一步提高大规模集约化现代化农业生产水平,提高农机管理水平,结合互联网络技术,与友谊农场农机管理部门合作,为友谊农场开发一套“农机管理网络信息系统”。该系统可以实现异地网络数据库访问和浏览,实现友谊农场农机网络化的管理,提高农机管理的科技水平,为友谊农场的农业现代化发展奠定了基础。     

Market penetration of ethanol

This research examines in detail the technology and economics of substituting ethanol for gasoline. This endeavor examines three issues. First, the benefits of ethanol/gasoline blends are examined, and then the technical problems of large-scale implementation of ethanol. Second, ethanol production possibilities are examined in detail from a variety of feedstocks and technologies. The feedstocks are the starch/sugar crops and crop residues, while the technologies are corn wet mill, dry grind, and lignocellulosic fermentation. Examining in detail the production possibilities allows the researchers to identity the extent of technological change, production costs, byproducts, and GHG emissions. Finally, a U.S. agricultural model, FASOMGHG, is updated which predicts the market penetration of ethanol given technological progress, variety of technologies and feedstocks, market interactions, energy prices, and GHG prices.FASOMGHG has several interesting results. First, gasoline prices have a small expansionary impact on the U.S. ethanol industry. Both agricultural producers’ income and cost both increase with higher energy prices. If wholesale gasoline is $4 per gallon, the predicted ethanol market penetration attains 53% of U.S. gasoline consumption in 2030. Second, the corn wet mill remains an important industry for ethanol production, because this industry also produces corn oil, which could be converted to biodiesel. Third, GHG prices expand the ethanol industry. However, the GHG price expands the corn wet mill, but has an ambiguous impact on lignocellulosic ethanol. Feedstocks for lignocellulosic fermentation can also be burned with coal to generate electricity. Both industries are quite GHG efficient. Finally, U.S. government subsidies on biofuels have an expansionary impact on ethanol production, but may only increase market penetration by an additional 1% in 2030, which is approximately 6 billion gallons.