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191.
This study focuses on the role of public capital stock in contributing to interstate differences in productive efficiency in manufacturing. Our motivation is to assess the role of public capital as a source of persistent regional variations in efficiency, and thus determine if public infrastructure policies might reasonably be expected to alter the competitive environment of a state's manufacturing sector. We use a stochastic frontier production function model, explicitly incorporating infrastructure capital, to examine the relative performance of the aggregate manufacturing sector across states and over time. We calculate an index of productive efficiency and estimate the determinants of statewide variations in it. These results show that variations in per capita infrastructure stocks significantly affect manufacturing efficiency. Considering the behavior of public capital as both a direct and an indirect input furthers our understanding of the role of infrastructure and its implications for regional economic development policies.  相似文献   
192.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.

Key points

  • Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
  • Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
  • These metrological principles also apply to individuation of unique objects in general.
  相似文献   
193.
大学是创新和社会进步的源泉   总被引:1,自引:0,他引:1  
大学是创新和社会进步的源泉。大学不仅可以支持并推动知识进步,更重要的贡献在于新发明和创新。由于大学长期关注基础性研究,因而比其他机构更容易开展创新活动。大学通过创新提高人们的生活水平、推动经济发展,进而推动社会的进步。易于创新的研究环境必须具有必要的内外部条件。内部条件主要有三个:一是要选对人;二是要时刻处于技术的前沿;三是要寻找那种跨越性的技术。外部条件主要有两个:一是大学与业界应互相尊重、相辅相成,形成双赢局面;二是创新的转化需要为技术突破提供肥沃的土壤和精心的照料。  相似文献   
194.
Coleman D  Casey JT 《危机》2007,28(4):198-203
The treatment processes associated with reduced suicidal ideation have received little research attention. This study evaluates the influence on suicidal ideation of theory-based intrapsychic processes: maladaptive cognition and defensive style. Thirty-three community mental health patients completed questionnaires at two time points. Decreases in automatic thoughts were a strong correlate of decreased suicidal ideation, and decreases in immature defenses were a moderate strength correlate. These relationships remained significant even when controlling for initial level of depression. The theorized mechanisms of cognitive-behavioral and psychodynamic therapy had the expected effects on suicidal ideation. The strong association of decreased maladaptive cognitions with decreased suicidal ideation supports further development of cognitive-behavioral suicide interventions and clinical use of cognitive interventions. Psychodynamic processes in suicidal ideation and behavior warrant further exploration.  相似文献   
195.
Milk maids     
Lee-St John J 《Time》2007,169(18):65
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196.
197.
Psychological Injury and Law - The extent to which persons may feign or malinger psychological symptoms is an important concern for civil litigation, specifically in the context of personal injury....  相似文献   
198.
Correspondence in value orientation between parents and their offspring may be due to actual transmission processes between generations, but it may also be due to influences from the general value context in society that are common to parents and their offspring. This common value context is referred to as Zeitgeist. The present study deals with one family relationship value (i.e., parents’ and adolescents’ obligations toward the family). Participants were 1,252 immigrant and 726 national adolescent–parent dyads from 10 Western countries. There were significant relationships between the value placed on family obligations among parents and offspring, and these were independent of gender. Zeitgeist effects, both intergenerational and intragenerational, were found. The strength of these Zeitgeist effects depended on the basis for defining Zeitgeist, either a person’s own ethnic group or the wider community including both nationals and immigrants. For explaining national adolescents’ acceptance of their family obligations, both the ethnic and the national Zeitgeist played a role, whereas in the immigrant groups only the ethnic Zeitgeist played a significant role. In short, in an immigration context it makes sense to distinguish the influence of a person’s own ethnic group from the influence of the wider community, including other ethnic groups. Explanations are suggested and implications are discussed.
Paul VedderEmail:
  相似文献   
199.
John R. Thelin 《Society》2018,55(6):556-559
Most colleges and universities in the United States face serious questions about missions, money, and morale in the 21st century. Some recent excellent books are useful for showing divergent perspectives on these problems. To one extreme, an historian tends to see that lack of planning has been an unexpected, enduring positive force. To another extreme, a high profile state university president draws on innovations in structure to deal with changes in demographics and academic fields. This review essay provides a balanced exploration of the disparate approaches, leading to the conclusion that American higher education is in need of a substantive "New Deal" in purposes and policies.  相似文献   
200.
We examine whether the existence of civil society in Georgia has promoted social and institutional trust in the population. As much of the literature suggests, Georgia is different from its neighbors in that civil society development is more advanced. Does participation in civil society lead to more social and institutional trust? Using survey data from the Caucasus Barometer and the World Values Survey, we find that attitudes regarding social and institutional trust are more developed in Georgia than in its neighbors, and that activity in voluntary organizations is positively associated with social and institutional trust in Georgia.  相似文献   
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