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11.
We examine the challenges of governance facing organizations that pursue a social mission through the use of market mechanisms. These hybrid organizations, often referred to as social enterprises, combine aspects of both charity and business at their core. In this paper we distinguish between two ideal types of such hybrids, differentiated and integrated, and we conceptualize two key challenges of governance they face: accountability for dual performance objectives and accountability to multiple principal stakeholders. We revisit the potential and limitations of recently introduced legal forms to address these challenges. We then theorize about the importance of organizational governance and the role of governing boards in particular, in prioritizing and aligning potentially conflicting objectives and interests in order to avoid mission drift and to maintain organizational hybridity in social enterprises. Finally, we discuss future research directions and the implications of this work for rethinking traditional categories of organizations, namely business and charity. 相似文献
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《Journal of Statistical Computation and Simulation》2012,82(8):1463-1478
In some situations, an appropriate quality measure uses three or more discrete levels to classify a product characteristic. For these situations, some control charts have been developed based on statistical criteria regardless of economic considerations. In this paper, we develop economic and economic statistical designs (ESD) for 3-level control charts. We apply the cost model proposed by Costa and Rahim.[Economic design of X charts with variable parameters: the Markov chain approach, J Appl Stat 28 (2001), 875–885] Furthermore, we assume that the length of time that the process remains in control is exponentially distributed which allows us to apply the Markov chain approach for developing the cost model. We apply a genetic algorithm to determine the optimal values of model parameters by minimizing the cost function. A numerical example is provided to illustrate the performance of the proposed models and to compare the cost of the pure economic and ESD for three-level control charts. A sensitivity analysis is also conducted in this numerical example. 相似文献
14.
In late 2009 China launched an innovative, voluntary programme that by 2011 had extended pension coverage to 326.4 million people in the rural sector, including contributors and beneficiaries. It requires one contribution per year and provides a flat‐rate benefit and a contributions‐related benefit through a contributory individual account, with a government guarantee that the benefit will continue for life. The programme encourages participation of persons who do not pay income taxes, and thus have no tax incentive to participate, by providing substantial government subsidies. As a further incentive, old‐age benefits are provided to older parents when all their adult children participate in the contributory programme. 相似文献
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Using In Vitro High‐Throughput Screening Data for Predicting Benzo[k]Fluoranthene Human Health Hazards
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Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods. 相似文献
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摘 要:应用儿童长处与困难(SDQ)问卷(父母版),采用分层随机抽样方法,对惠州市1528名3-6岁儿童的情绪与行为问题进行调查。研究发现:惠州市3-6岁儿童情绪与行为问题异常情况比较严峻,儿童心理健康状况值得重视;不同地域、年龄学前儿童存在不同的情绪与行为问题,需要分类干预。其中农村儿童的情绪与行为问题异常情况尤为严重,需要得到广泛的关注和解决。 相似文献
18.
Angela Swift Joan Webster Annette Mary Conroy Sue Hampton Sarah Jane Kirby Lee Minuzzo Rebecca Kimble 《Women and birth : journal of the Australian College of Midwives》2014,27(3):163-167
BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable. 相似文献
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Methods for a sequential test of a dose-response effect in pre-clinical studies are investigated. The objective of the test procedure is to compare several dose groups with a zero-dose control. The sequential testing is conducted within a closed family of one-sided tests. The procedures investigated are based on a monotonicity assumption. These closed procedures strongly control the familywise error rate while providing information about the shape of the dose-responce relationship. Performance of sequential testing procedures are compared via a Monte Carlo simulation study. We illustrae the procedures by application to a real data set. 相似文献
20.
提出在并联机构中应用一种1移动3转动半开式滑槽球副结构,该运动副将1个移动副和1个球副集成为一个复合的运动副,可以缩短并联机构中支链的尺寸链,有助于提高并联机构精度。基于半开式滑槽球副设计了一种3自由度(3-DOF)PSP三轴并联平台,通过对此机构进行的运动分析和支链的精度分析,导出各个支链的逆解方程,同时根据影响支链运动精度的各个因素给出支链系统误差的线性补偿方程,证明此并联机构具有易于控制、运动精度高的优势。 相似文献