影响蓖麻种子萌发因子的研究

对蓖麻种子萌发进行温度、水分、播种深度、种皮等处理试验，结果表明，温度和播种深度显著影响蓖麻种子萌发，其中土壤温度低和覆土厚是导致蓖麻种子萌发缓慢的主要因子;种皮的存在有利于菌麻种子萌发;土壤水分含量在10％以上能满足蓖麻种子萌发。     

15%保丰1号种衣剂拌种防治小麦白粉病田间药效试验

进行了 1 5 %保丰 1号种衣剂不同使用剂量与多菌灵、三唑酮及空白对照对小麦白粉病的田间药效试验。结果表明 :1 5 %保丰 1号种衣剂能有效防治小麦白粉病 ,其防效优于三唑酮和多菌灵 ,以 1 5 %保丰 1号种衣剂 40 0g有效成分拌 1 0 0kg小麦种子对白粉病的防效最佳     

To be or not to be: Control and balancing of type I and type II errors

The various costs of Type I and Type II errors of inference from data are discussed. Unfortunately, other things equal, Types I and II errors are inversely related. Six methods of minimizing Type I error in studies are presented, each of which may be employed even after data are collected. Type II errors may also be minimized by a combination of study design and analytic means. Although some of these techniques must be built into the study others can be undertaken when beginning work on a data set. Only one of these techniques will increase Type I error, and those involving data reduction may decrease both types of error.     

我国种子行政执法责任制度分析

我国种子产业进入快速发展阶段并取得显著成效,我国种业的安全发展离不开种子行政执法工作的保驾护航,种子行政执法年对种子行政执法有了更高的要求,而种子行政执法责任制度则是对种子行政执法工作的最后一道保障防线。目前我国种子行政执法责任制度的发展还很不完善,相应的责任制度还没有完全建立,已有的责任制度在运行施行上也面临诸多问题,这是利益博弈与规制俘获的产物,更是公众参与机制不健全的体现。分析种子行政执法的责任分解制度、责任考评制度、责任监督制度、责任追究制度以及公众参与作为运行保障措施,以期能完善我国种子行政执法责任制度,规范种子行政执法工作。     

人道主义旗帜下的民族主义走向——论赛珍珠《龙子》的战争视角

作为一部支持中国抗战的长篇小说,《龙子》不仅是对日军暴行的揭露,也是对一切暴力的反思。《龙子》自觉透视战争背景下民族意识的觉醒与高涨,冷静地揭示民族主义扭曲发展对人性的伤害,并从人道主义的高度思考民族主义的走向。这种观照战争的视角充分显示了赛珍珠独到的眼光和见地。     

一部真实再现中国人民抗日战争历史的扛鼎之作--论赛珍珠的长篇小说《龙子》

赛珍珠的长篇小说<龙子>忠实记录了日军在华的种种残暴行径,真实再现了中国人在抗日战争初期、中期的心路历程,真切反映了中国人民反抗日本侵略的英雄壮举,同时,深刻反省了战争扭曲人性所带来的严重恶果.可以说,<龙子>是一部真实再现中国人民英勇抗战的史诗.     

濒危植物蒙古扁桃种子特性及萌发生理研究

本文对蒙古扁桃种子特性及萌发影响因素进行了初步研究。实验结果表明:蒙古扁桃千粒重为157.9±4.5g,去除内果皮后,种子较易萌发;活种子的吸水力较高,从开始浸泡起,前2h是种子快速吸胀期;通过用TTC法测种子活力可知,去除果皮后,蒙古扁桃种子活力高达100%;用TTC法测种子萌发过程中脱氢酶活性时,可知脱氢酶的活性很高,且在不同萌发时间,脱氢酶的活性不一,吸胀后3h脱氢酶的活性最高,高达89.7%。室温、自然光照下,蒙古扁桃种子发芽率为86.67%;在1—2cm深的土壤中,种子出苗率可达100%,超过3cm,显著下降;蒙古扁桃种子萌发时土壤的最适湿度为15%—25%,低于15%或高于25%出苗率显著下降;土壤湿度对幼苗存活率有极显著影响,湿度为20.26%时,幼苗死亡率高达50%。     

Sex stratification in the workplace: Male-female differences in economic returns to occupation

Employing data from the 1974–1977 NORC General Social Surveys, I investigate differences in the earnings attainment of currently employed white men and women age 25 to 64. I focus special attention on the explanatory effects of job characteristics other than those traditionally employed in prestige and status-defined earnings models. The results, based on a multivariate regression analysis and a regression standardization procedure, suggest that a nontrivial portion of the earnings gap between men and women is due to women's concentration in jobs which are low-paying and heavily female and because women are less likely than men to exercise authority in their jobs or to control the means of production. Including these factors in an earnings model statistically increases women's earnings as a percentage of men's by over 7%, accounting for approximately 13% of the earnings gap. Net of these job characteristics, gender differences in industry distribution are not substantively important in explaining why women earn less than men, accounting for only 0.4% of the earnings gap. When single women's earnings are adjusted to take account of their occupational concentration, 10% of the male-single female earnings gap is explained, providing preliminary evidence that the job characteristics I specify are not mere proxies for work experience. Including job characteristics as measures of the context of employment thus usefully extends the human capital and prestige or statusdefined models traditionally employed in explanations of the male-female earnings differential.     

Supply Chains in Sub‐Saharan Africa: A Decision Support System for Small‐Scale Seed Entrepreneurs*

It is necessary to infuse a consistent supply of improved seed varieties into local sub‐Saharan African crop production to improve low crop yields. The best distribution channel for the improved seed varieties may be small‐scale commercial seed companies, but local entrepreneurs struggle to determine whether such businesses are viable. Using a multi‐echelon supply chain approach, a decision support system (DSS) was designed to help African seed entrepreneurs make informed decisions about small‐scale seed chain businesses. Specifically, entrepreneurs make decisions about where to locate seed enterprises, with which farmers to contract, and where to store seed. Optimization and simulation modeling are used to evaluate infrastructure variables such as distance, transportation cost, and storage loss and cost in three development level areas. Currently, the decision tool is used in Mozambique, Malawi, Kenya, and Tanzania. The model has supported the start‐up of at least 17 small seed companies that are now introducing improved seed varieties into villages and farms. The DSS applies decision science research in a humanitarian application and offers important managerial implications about supply chain infrastructure to nongovernmental organizations and humanitarian groups. Such applications are vital as groups such as USAID, the Gates Foundation, and the International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT) continue to move toward micro‐enterprise, value chain, and market‐oriented development programs.