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201.
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   
202.
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   
203.
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   
204.
Milk maids     
Lee-St John J 《Time》2007,169(18):65
  相似文献   
205.
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   
206.
207.
This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three “parent” devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical “daughter” devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent–daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain.  相似文献   
208.
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   
209.
This paper analyses contrasting discourses of ‘climate-smart agriculture’ (CSA) for their implications on control over and access to changing resources in agriculture. One of the principal areas of contestation around CSA relates to equity, including who wins and who loses, who is able to participate, and whose knowledge and perspectives count in the process. Yet to date, the equity implications of CSA remain an under-researched area. We apply an equity framework centred on procedure, distribution and recognition, to four different discourses. Depending on which discourses are mobilised, the analysis helps to illuminate: (1) how CSA may transfer the burden of responsibility for climate change mitigation to marginalised producers and resource managers (distributive equity); (2) how CSA discourses generally fail to confront entrenched power relations that may constrain or block the emergence of more ‘pro-poor’ forms of agricultural development, adaptation to climate change, or carbon sequestration and storage (procedural equity); (3) how CSA discourses can have tangible implications for the bargaining power of the poorest and most vulnerable groups (recognition). The paper contributes to work showing the need for deeper acknowledgement of the political nature of the transformations necessary to address the challenges caused by a changing climate for the agricultural sector.  相似文献   
210.
Straka  John W.  Straka  Brenda C. 《Policy Sciences》2020,53(4):779-802
Policy Sciences - Persistent policy failures have been examined in recent years with a focus on the role of political systems. We evaluate the growth of dysfunctional policymaking in the U.S. and...  相似文献   
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