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141.
This article presents an overlooked case of research misconduct and violations of basic principles of medical and business ethics. When Bayer’s Cutter Laboratories realized that their blood products, Factor VIII and IX or antihemophiliac factor (AHF), were contaminated with human immunodeficiency virus (HIV), the financial investment in the product was considered too high to destroy the inventory. Cutter misrepresented the results of its own research and sold the contaminated AHF to overseas markets in Asia and Latin America without the precaution of heat treating the product recommended for eliminating the risk. As a consequence, hemophiliacs who infused the HIV-contaminated Factor VIII and IX tested positive for HIV and developed AIDS. 相似文献
142.
《Journal Of Human Behavior In The Social Environment》2013,23(3-4):177-194
SUMMARY The Secondary Traumatic Stress Scale (STSS; Bride, Robinson, Yegidis, & Figley, 2004) is an easy to administer 17-itemself-report measure of secondary trauma. Bride et al. (2004) reported a measure of three domains of traumatic stress specifically associated with secondary exposure to trauma: intrusion, avoidance, and arousal. The STSS was reported to have high levels of internal consistency reliability and indicated evidence of convergent, discriminant, and factorial validity. The purpose of this paper is to examine the reliability and validity of the STSS with a national, random sample of mental health social workers. To assess the fit of the data to the three-factor structure proposed by Bride et al., a confirmatory factor analysis was performed on data from 275 social workers who indicated exposure to client trauma. The model fit the data adequately although high factor intercorrelations strongly suggest a unidimensional scale. Subsequent confirmatory factor analysis of a unidimensional scale and a second order factor analysis yielded similar results. Findings indicate the need for further scale validation. Challenges remain for measuring and distinctly differentiating between secondary trauma symptoms of arousal, avoidance, and intrusion. Implications and suggestions for future research are discussed. 相似文献
以子博弈完美纳什均衡作为分析工具,分析了电子商务与物流服务发展的不均衡现象,并将网购过程中卖方与快递企业之间的讨价还价过程与贴现因子联系起来,通过模型在节假日期间的应用,从贴现因子对均衡解的影响分析了卖方与快递企业的利益变化。最终得出结论,贴现因子是影响卖方与快递企业所承担的快递费用的重要因素并提出了相应建议。 相似文献
144.
We propose a semiparametric approach for the analysis of case–control genome-wide association study. Parametric components are used to model both the conditional distribution of the case status given the covariates and the distribution of genotype counts, whereas the distribution of the covariates are modelled nonparametrically. This yields a direct and joint modelling of the case status, covariates and genotype counts, and gives a better understanding of the disease mechanism and results in more reliable conclusions. Side information, such as the disease prevalence, can be conveniently incorporated into the model by an empirical likelihood approach and leads to more efficient estimates and a powerful test in the detection of disease-associated SNPs. Profiling is used to eliminate a nuisance nonparametric component, and the resulting profile empirical likelihood estimates are shown to be consistent and asymptotically normal. For the hypothesis test on disease association, we apply the approximate Bayes factor (ABF) which is computationally simple and most desirable in genome-wide association studies where hundreds of thousands to a million genetic markers are tested. We treat the approximate Bayes factor as a hybrid Bayes factor which replaces the full data by the maximum likelihood estimates of the parameters of interest in the full model and derive it under a general setting. The deviation from Hardy–Weinberg Equilibrium (HWE) is also taken into account and the ABF for HWE using cases is shown to provide evidence of association between a disease and a genetic marker. Simulation studies and an application are further provided to illustrate the utility of the proposed methodology. 相似文献
145.
企业技术创新的风险研究 总被引:1,自引:0,他引:1
周勇 《西安建筑科技大学学报(社会科学版)》2001,20(1):37-39,53
技术创新是一项高风险的活动,本文对技术创新中存在的风险因素及其在各阶段的主要表现进行了系统的分析和论述,并提出了风险防范的几项措施. 相似文献
146.
黄金贵 《浙江大学学报(人文社会科学版)》2002,32(1):39-45
识同是决定同义词辨释优劣高下的首要问题.在认识"一义相同"是同义词识同的标准后,就要解决如何识别一群词"一义相同"的问题.不少的研究者曾提出许多识同方法,但都由于不明同义词的正确界说和误解等义词而不能成功.事实上,从词义的相同程度,同义词可分理性意义等同而附加意义有异的异称词和理性意义有同中之异的一般同义词. 对前一类,可围绕异名别称,用"同一概念"和"同一对象"两种识同法;对后一类,可围绕一个词义的主要、基本部分相同,用"浑言通义"识同法;还应该运用可共用于这两类的文献训诂材料识同法、古人替换使用识同法. 相似文献
147.
市场预测支持系统的预测模型研究 总被引:1,自引:0,他引:1
本文运用模糊数学和统计相关的理论,预测支持系统确定预测量的相关因子,分析了建造预测模型的过程,给出了待预测量的预测模型,并验证之。 相似文献
148.
149.
影响川南浅丘区田坎玉米产量的气候条件分析 总被引:1,自引:0,他引:1
利用积分回归方法分析气候因子对川南浅丘区田坎玉米产量的影响。结果表明 ,日照、温度及降雨日数是影响田坎玉米产量的主要因子。苗期的高温 ,生育中期光照不足及灌浆成熟期的雨日偏多均不利于提高田坎玉米产量 相似文献
150.
BOOST-PFC电路反馈环节的优化设计 总被引:1,自引:0,他引:1
介绍了平均电流控制BOOST─PFC电路的原理,建立了电流环和电压环的小信号简化模型,讨论了双环反馈环节的设计原则和方法,提出最优设计的思想和数学模型,并以一种BOOST─PFC电路为例进行优化设计,计算模拟结果显示优化后有关指标好于优化前。 相似文献