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141.
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   
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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   
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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   
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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   
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The need to grasp the complexity of contemporary China is more urgent than ever The year 2021 is a big year for the People's Republic of China. Midyear will see the 100 th anniversary of the founding of the Communist Party of China. It will also mark one of the nation's centennial goals, referred to over the last few years, when the country achieves a moderately prosperous status. A lot of planning has already gone into how things will happen in July. At least, within China, there will be a lot going on.  相似文献   
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A PEOPLE'S PARTY     
As an organization, there can be few in modern history that have had so much impact on the world as the Communist Party of China (CPC). Since 1949, it has been the ruling party in a country whose population comprises a fifth of humanity. That alone means it merits attention and study. But in addition to this, over that time, it has also seen the People's Republic of China (PRC) grow from a country with huge developmental and economic challenges to the world's second largest economy, and one of its great modern powers. In this way, the CPC has become increasingly important for the outside world to understand as the impact of the country's economic growth increases.  相似文献   
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