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11.
Starting in 2006, respondents in the biennial U.S. Health and Retirement Study were asked to submit biomarkers every other wave and were notified of several results. Rates of undiagnosed high blood pressure and diabetes according to these biomarkers were 1.5 % and 0.7 %, respectively. An intent-to-treat analysis suggests that collection and notification had small effects on the average respondent and may have reduced health care utilization. Among respondents who received notification of potentially dangerous biomarker levels, subsequent rates of new diagnosis and associated pharmaceutical usage increased by 20 to 40 percentage points, an order of magnitude above baseline. High blood glucose A1C was associated with a 2.2 % drop in weight and an increase in exercise among respondents without a previous diagnosis of diabetes. Notifications appear also to have altered health behaviors by spouses, suggesting household responses to health maintenance. Biomarker collection seems to have altered circumstances for an interesting minority of HRS respondents.  相似文献   
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机械产品的设计一直注重于市场需求和产品功能的开发,随着科学和技术的发展,环境因素变得越来越重要。 提出一种基于功能一环境一结构分析( FESA)与TRIZ的机械产品创新设计方法,通过分析机械产品结构之间的功能要素 以及功能要素与环境要素的相互作用关系,确定机械产品中存在的问题。建立根原因模型图,寻找结构设计上的不足和 缺陷,利用TRIZ创新理论来实现机械产品的改进创新。通过污水处理系统的创新设计实例验证了该方法的可行性。  相似文献   
14.
湘鄂川黔革命根据地是长江南岸的最后一块红色根据地,是在全国其他各路红军离开原有根据地后,由红二、六军团会师后建立的,为我国革命战争的胜利起到了不可忽视的作用。文章以"扩红运动"为研究维度,从三个方面进行深刻论析。面对国民党的"围剿"、根据地内反动势力的迫害以及薄弱的地方武装力量,"扩红运动"的组织发动显得迫切需要。"扩红运动"的组织发动不仅对打击封建反动势力、维护苏维埃政权、壮大革命队伍、策应红军长征,以及保卫土地革命成果、扩大中国共产党的影响有着重要的历史意义,而且还对当今密切党群关系、处理民族关系、加强军队建设等都有着重要的现实意义。  相似文献   
15.
In the partial degree bounded edge packing problem (PDBEP), the input is an undirected graph \(G=(V,E)\) with capacity \(c_v\in {\mathbb {N}}\) on each vertex v. The objective is to find a feasible subgraph \(G'=(V,E')\) maximizing \(|E'|\), where \(G'\) is said to be feasible if for each \(e=\{u,v\}\in E'\), \(\deg _{G'}(u)\le c_u\) or \(\deg _{G'}(v)\le c_v\). In the weighted version of the problem, additionally each edge \(e\in E\) has a weight w(e) and we want to find a feasible subgraph \(G'=(V,E')\) maximizing \(\sum _{e\in E'} w(e)\). The problem is already NP-hard if \(c_v = 1\) for all \(v\in V\) (Zhang in: Proceedings of the joint international conference on frontiers in algorithmics and algorithmic aspects in information and management, FAW-AAIM 2012, Beijing, China, May 14–16, pp 359–367, 2012). In this paper, we introduce a generalization of the PDBEP problem. We let the edges have weights as well as demands, and we present the first constant-factor approximation algorithms for this problem. Our results imply the first constant-factor approximation algorithm for the weighted PDBEP problem, improving the result of Aurora et al. (FAW-AAIM 2013) who presented an \(O(\log n)\)-approximation for the weighted case. We also study the weighted PDBEP problem on hypergraphs and present a constant factor approximation if the maximum degree of the hypergraph is bounded above by a constant. We study a generalization of the weighted PDBEP problem with demands where each edge additionally specifies whether it requires at least one, or both its end-points to not exceed the capacity. The objective is to pick a maximum weight subset of edges. We give a constant factor approximation for this problem. We also present a PTAS for the weighted PDBEP problem with demands on H-minor free graphs, if the demands on the edges are bounded by polynomial. We show that the PDBEP problem is APX-hard even for bipartite graphs with \(c_v = 1, \; \forall v\in V\) and having degree at most 3.  相似文献   
16.
Quality-of-life studies have a 50-year history and inherited the tradition of the “social indicators” movement, born in the United States during the sixties and involving scholars and researchers, supported by the public administration and interested in gathering and analysing data aimed at studying non-economic components of societal wellbeing. The idea of quantifying “symptoms” (indicators) of living conditions has been launched by Italian statistician and criminologist, Alfredo Niceforo, who has been recognised as the pioneer of social-indicators concept. Moreover, with his book on Les indices numérique de la civilisation et du progrès, he may be considered the originator of an approach of comprehensive welfare and quality of life measurement as it is the concern of modern social indicators and quality of life.  相似文献   
17.
The longstanding focus of elite athletes on top sports entails disadvantages hampering their later entry to the world of work. In order to successfully contribute their outstanding personality traits to a later job, athletes are thus particularly required to care for their employability. Contributing to this, the author carried out a competency balancing with top athletes. This coaching method significantly decreased the athletes’ need for self-information. Evaluation further showed indications of increased clarity and certainty of occupational goals as well as work satisfaction.  相似文献   
18.
A simple connected graph G with 2n vertices is said to be k-extendable for an integer k with \(0<k<n\) if G contains a perfect matching and every matching of cardinality k in G is a subset of some perfect matching. Lakhal and Litzler (Inf Process Lett 65(1):11–16, 1998) discovered a polynomial algorithm that decides whether a bipartite graph is k-extendable. For general graphs, however, it has been an open problem whether there exists a polynomial algorithm. The new result presented in this paper is that the extendability problem is co-NP-complete.  相似文献   
19.
We revise existing and introduce new mixed-integer programming models for the Multiprocessor scheduling problem with communication delays. The basis for both is the identification of two major modeling strategies one of which can be considered ordering-based, and the other assignment-based. We first reveal redundancies in the encoding of feasible solutions found in present formulations and discuss how they can be avoided. For the assignment-based approach, we propose new inequalities that lead to provably stronger continuous relaxations and better performance in practice. Moreover, we derive a third, novel modeling strategy and show how to more compactly linearize assignment formulations with quadratic constraints. In a comprehensive experimental comparison of representative models that reflect the state-of-the-art in terms of strength and size, we evaluate not only running times but also the obtained lower and upper bounds on the makespan for the harder instances of a large scale benchmark set.  相似文献   
20.
Klassen messen     
The article investigates whether Austrian sociological research empirically addressed social class conceptions between 1945 and 1990. Contrary to the German reception, we find that, indeed, during the whole period scientific publications analyzed social relations and social change from a class perspective with an empirical approach. We embed this research in its historical context in order to work out the implicit explanations given concerning the existence of social inequalities. Moreover, we work out if post-World War II Austrian class analysis did link its work to the Austro-Marxist tradition that flourished between the two World Wars. The empirical focus of the article lies on scientific publications with an empirical approach to social classes and social change.  相似文献   
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