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191.
This article examines the contract design decisions of three federal agencies—the Departments of Health and Human Services, Defense, and Homeland Security—using five years of data from the Federal Procurement Data System. Three basic contract design elements are charted—type (fixed price versus cost reimbursement), length, and value—across simple to complex products. All three agencies use short‐term, fixed‐price contracts for the majority of the purchases that they make. This basic contract design allows agencies to tap the benefits of competition: innovation and cost‐efficiency. However, the Departments of Defense and Homeland Security often dramatically increase the length and value of contracts through modifications to initial agreements. This approach forgoes the benefits of competition and may expose the agency to the risk of cost overruns, delivery delays, and diminished product quality.  相似文献   
192.

Purpose

This article provides a critical review of the state of research on the gang membership-violent victimization relationship.

Methods

This study examines a comprehensive list of published quantitative studies that have assessed the relationship between gang membership and violent victimization.

Results

By examining strengths and weaknesses of the design features of various studies, this article identifies theoretical, conceptual, methodological, and statistical issues that should be considered when interpreting the causal effect of gang membership on violent victimization. Some of the methodological and design issues discussed include, but are not limited to, consequences of failing to establish temporal order, failure to conduct sensitivity analyses to determine treatment effects, use of bootstrapping methods with propensity score analysis, measurement of violent victimization, and corrections for dependence in matched samples of gang and non-gang members.

Conclusion

Suggestions for future research are provided that will help advance the empirical study of the gang membership-violent victimization nexus.  相似文献   
193.
As the challenges of maintaining (or, in the US case, attaining) affordable universal coverage multiply, the debate about what constitutes "real" reform intensifies in Western health care systems. The reality of reform, however, lies in the eyes of myriad beholders who variously enshrine consumer responsibility, changes in payment systems, reorganization, and other strategies -- or some encompassing combination of all of the above -- as the essential ingredient(s). This debate, increasingly informed by the agendas of health services researchers and health policy analysts, arguably serves as much or more to becloud as to clarify the practical options policy makers face and remains severely imbalanced with respect to the institutional sectors on which it concentrates, the fields of knowledge on which it draws, and the roles it envisions for markets and the state.  相似文献   
194.
This article describes the use of an anti-Stokes luminescent material (upconverter), yttrium vanadate doped with ytterbium and erbium (YVO(4):Er,Yb), for the development of latent fingermarks on a range of non-porous surfaces. Anti-Stokes luminescent materials emit light at shorter wavelengths than the excitation wavelength. This property is unusual in both natural and artificial materials commonly found as exhibits in forensic science casework. As a result, fingermark detection techniques based on anti-Stokes luminescence are potentially extremely sensitive and selective. Latent fingermarks on non-luminescent and inherently luminescent substrates, including Australian polymer banknotes (a well-known 'difficult' surface), were developed with YVO(4):Er,Yb by dry powder and wet powder techniques. The effectiveness of YVO(4):Er,Yb for fingermark detection was compared with that of cyanoacrylate fuming and of sodium yttrium tetrafluoride doped with ytterbium and erbium (NaYF(4):Er,Yb). The results illustrate some benefit of luminescent up-converting phosphors over traditional luminescence techniques for the detection of latent fingermarks.  相似文献   
195.
Other papers in this edition of the European Journal of Criminal Policy and Research use mainly statistics collected through the European Sourcebook on Crime and Justice Statistics but there are many other sources of international statistics collected by different agencies for different purposes. This paper critically examines the main current and planned collections of comparative data within the European community and wider international bodies. Full Web references are given of available questionnaires and publications where these exist. It also discusses the importance of comparative data generally and pitfalls in its interpretation and examines the guidelines published by international bodies to assist with data collection on crime and justice. Finally, the future of comparative data collections is discussed and recommendations are made.  相似文献   
196.
正Dear Readers,Forum is a column that provides a space for varying perspectives on contemporary Chinese society.We invite you to submit personal viewpoints on past and current topics(in either English or Chinese).yanwei@bjreview.com Please provide your name and address along with your comments Deng Xiaoping’s role as the father of reform in modern China is historically secure.In his vast biography of the Chinese leader published in 2011,American academic  相似文献   
197.
198.
Moral Foundations Theory posits five distinct foundations of morality: Harm/Care, Fairness/Reciprocity, In-group/Loyalty, Authority/Respect, and Purity/Sanctity. In combination, this should yield between four-to-six moral signatures—distinct combinations or patterns of support for these aspects of morality. We extend previous research by examining the replicability of these moral signatures in a New Zealand-based national sample (n = 3,635). Latent Profile Analysis identified four distinct moral signatures: Individuators, Moderates, Neutrals, and High Moralists. We integrate these moral signatures within the Dual Process Model (DPM) framework and show that Social Dominance Orientation predicts membership in the Neutral moral signature (moderate/lukewarm support for multiple moral foundations); whereas Right-Wing Authoritarianism predicts membership in the High Moralist signature (undifferentiated high support across moral foundations). These findings were observed controlling for Big-Six personality and various demographics. Thus, the authoritarian and dominance-based motives identified by the DPM independently predict categorical differences in the signatures people use to judge morality.  相似文献   
199.
Forensic fractographic features of bone reliably establish crack propagation in perimortem injuries. We investigated if similar fracture surface features characterize postmortem fractures. Experimentally induced peri- and postmortem fractures were used to assess if fractographic features vary as bone elasticity decreases during the postmortem interval (PMI). Thirty-seven unembalmed, defleshed human femoral shafts from males and females aged 33–81 years were fractured at varying PMIs with a drop test frame using a three-point bending setup and recorded with a high-speed camera. Vital statistics, cause of death, PMI length, temperature, humidity, collagen percentage, water loss, fracture energy, and fractography scores were recorded for each sample. Results showed that fractographic features associated with perimortem fractures were expressed in PMIs up to 40,600 accumulated degree hours (ADH), or 60 warm weather days. Hackle was the most consistently expressed feature, occurring in all fractures regardless of ADH. The most variable characteristics were wake features (78.4%) and arrest ridges (70.3%). Collagen percentage did not correlate strongly with ADH (r = −0.04, p = 0.81); however, there was a strong significant correlation between ADH and water loss (r = 0.74, p < 0.001). Multinomial logistic regression showed no association between fractographic feature expression and ADH or collagen percentage. In conclusion, forensic fractographic features reliably determine initiation and directionality of crack propagation in experimentally induced PMIs up to 40,600 ADH, demonstrating the utility of this method into the recent postmortem interval. This expression of reliable fractographic features throughout the early PMI intimates these characteristics may not be useful standalone features for discerning peri- versus postmortem fractures.  相似文献   
200.
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