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51.
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.
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Self-determination theory emphasizes the importance of school-based autonomy and belongingness to academic achievement and psychological adjustment,
and the theory posits a model in which engagement in school mediates the influence of autonomy and belongingness on these
outcomes. To date, this model has only been evaluated on academic outcomes. Utilizing short-term longitudinal data (5-month
timeframe) from a set of secondary schools in the rural Midwest (N = 283, M age = 15.3, 51.9% male, 86.2% White), we extend the model to include a measure of positive adjustment (i.e., hope). We also
find a direct link between peer-related belongingness (i.e., peer support) and positive adjustment that is not mediated by
engagement in school. A reciprocal relationship between academic autonomy, teacher-related belongingness (i.e., teacher support)
and engagement in learning is supported, but this reciprocal relationship does not extend to peer-related belongingness. The
implications of these findings for secondary schools are discussed.
相似文献
Mark J. Van RyzinEmail: |
55.
This research analyzes the individual-level factors associated with public support for the private provision of public goods and services. Given that privatization requires the transfer of authority from public to private entities, we argue that beliefs about private companies are an important and overlooked source of heterogeneity in explaining public policy preferences toward privatization. We test this expectation using survey data from the 2014 Cooperative Congressional Election Study. We find that support for privatization is associated with positive beliefs about the motivation of private companies and with favorable views about corporate accountability relative to the accountability of government. Opposition to privatization is associated with beliefs about corporate influence in politics. Preferences for limited government are also associated with support for privatization. These results highlight the potential for beliefs about private companies to serve as a group heuristic in political reasoning and the ability of citizens to make reasoned choices on complex public policy issues. 相似文献
56.
The mismatch between the housing needs of persons with a disability and the housing programs designed to accommodate those needs is an important housing policy concern. The U.S. Department of Housing and Urban Development (HUD) sponsors several programs designed to improve the housing conditions of persons with a disability, but we know little about the characteristics of persons with a disability, among those receiving federal housing assistance, or the degree to which persons with a disability are served by HUD-sponsored housing programs that are designed to meet the needs of persons with a disability. Our study relies on administrative data from HUD and the U.S. Census Bureau to address this research gap. We find that many persons with a disability are served by HUD-sponsored programs that are not designated for persons with a disability, even when disability accommodations have been requested, and a similarly large share of persons with a disability live in potentially eligible low-income households that do not receive HUD assistance. 相似文献
57.
Mark Sandford 《Regional & Federal Studies》2017,27(1):63-82
Initial analyses of the ‘devolution deals’ that form the cornerstone of current efforts to devolve power within England assess the policy against conventional governance criteria: accountability, transparency, and the quality of governance systems. In fact, English devolution policy has little connection with territorial governance. Instead, it closely resembles a contractual process, with central government determining the terms on which it will outsource specified programmes and projects to local governments, complete with requirements for ‘business readiness’, implementation plans, evaluation requirements, and future joint working. Accountability, governance and even geography take second place to the aim of improving central policy outcomes via a contract-style relationship. This perspective is styled ‘post-territorial devolution’: it accounts more effectively for the shape of the policy so far than traditional governance perspectives, which are often laced with normative positions. 相似文献
58.
Recent case studies and large-N survey evidence has confirmed long-suspected shortages of public sector “policy capacity”. Studies have found that government policy workers in various jurisdictions differ considerably with respect to types of policy work they undertake, and have identified uneven capacity for policy workers to access and apply technical and scientific knowledge to public issues. This suggests considerable difficulties for government’s ability to meet contemporary policy and governance challenges. Despite growing attention to these matters, studies have not examined the “elite” policy workers many governments recruit to address these capacity shortages. Using an established survey instrument, this study of two Canadian recruitment programs provides the first comparative analysis of elite policy recruits, as policy workers. Three research questions anchor the study: (1) What is the profile of these actors? (2) What types of policy work do “elite” policy analysts actually engage in? (3) How does their policy work compare by recruitment program? The article provides fresh comparative data on the nature of elite policy work and policy analytical capacity, but, more importantly, a crucial baseline for future comparative study of how elite recruitment may facilitate “supply-side” capacity gains expected from recruitment programs. 相似文献
59.
Explanations for national success in science and technology typically focus on domestic institutions and policies. However, that line of research has yet to identify any particular set of institutions or policies that explain variation in national innovation rates across cases or over time. This article offers new evidence that the problem with domestic institutions approaches stems from their failure to consider international security factors. Specifically, this article finds a positive effect for U.S. security alliances on innovation. This finding is robust across different specifications and periods of analysis. While countries that ally militarily with the United States are found to realize benefits in economy‐wide, indigenous innovation, such an effect is not observed in military technologies. This suggests that alliances may substitute for being on the frontier in military technologies. Therefore, this article contributes not just to debates over S&T competitiveness, but also to alliance formation. 相似文献
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