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61.
62.
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks.  相似文献   
63.
64.
Volatile organic compounds (VOCs) are by-products of cadaveric decomposition and are responsible for the odor associated with decomposing remains. The direct link between VOC production and individual postmortem microbes has not been well characterized experimentally. The purpose of this study was to profile VOCs released from three postmortem bacterial isolates (Bacillus subtilis, Ignatzschineria indica, I. ureiclastica) using solid-phase microextraction arrow (SPME Arrow) and gas chromatography–mass spectrometry (GC-MS). Species were inoculated in headspace vials on Standard Nutrient Agar and monitored over 5 days at 24°C. Each species exhibited a different VOC profile that included common decomposition VOCs. VOCs exhibited upward or downward temporal trends over time. Ignatzschineria indica produced a large amount of dimethyldisulfide. Other compounds of interest included alcohols, aldehydes, aromatics, and ketones. This provides foundational data to link decomposition odor with specific postmortem microbes to improve understanding of underlying mechanisms for decomposition VOC production.  相似文献   
65.
Objectives

While block randomized designs have become more common in place-based policing studies, there has been relatively little discussion of the assumptions employed and their implications for statistical analysis. Our paper seeks to illustrate these assumptions, and controversy regarding statistical approaches, in the context of one of the first block randomized studies in criminal justice—the Jersey City Drug Market Analysis Project (DMAP).

Methods

Using DMAP data, we show that there are multiple approaches that can be used in analyzing block randomized designs, and that those approaches will yield differing estimates of statistical significance. We develop outcomes using both models with and without interaction, and utilizing both Type I and Type III sums-of-squares approaches. We also examine the impacts of using randomization inference, an approach for estimating p values not based on approximations using normal distribution theory, to adjust for possible small N biases in estimating standard errors.

Results

The assumptions used for identifying the analytic approach produce a comparatively wide range of p values for the main DMAP program impacts on hot spots. Nonetheless, the overall conclusions drawn from our re-analysis remain consistent with the original analyses, albeit with more caution. Results were similar to the original analyses under different specifications supporting the identification of diffusion of benefits effects to nearby areas.

Conclusions

The major contribution of our article is to clarify statistical modeling in unbalanced block randomized studies. The introduction of blocking adds complexity to the models that are estimated, and care must be taken when including interaction effects in models, whether they are ANOVA models or regression models. Researchers need to recognize this complexity and provide transparent and alternative estimates of study outcomes.

  相似文献   
66.
67.
While having a purpose in life has been theorized as a developmental asset, the extent to which adolescents cultivate a meaningful sense of direction is not well understood. In the present study, cluster analysis was used to classify adolescents by levels of purpose exploration and commitment. The sample (N = 318; 55% female) consisted of youth aged 14–18 and was predominantly White/non-Hispanic (76.3%). Results supported four meaningful yet distinguishable profiles of youth purpose that are largely consistent with theories on identity formation: Achieved, Foreclosed, Uncommitted, and Diffused. Hypothesized linkages with affect and hope were established across the profiles such that positive emotions and goal-directed thinking were most apparent among Achieved and Foreclosed youth and least apparent among Diffused and Uncommitted youth. Overall, findings demonstrate the inherent complexity in adolescents’ engagement with purpose and suggest a correspondence between stronger commitments to purpose and youths’ sense of personal agency and well-being.  相似文献   
68.
Research on the mechanisms by which interparental conflict (IPC) affects child depression suggests that both parenting and children’s conflict appraisals play important roles, but few studies have explored the role of general cognitive style or included both parenting and cognitions in the same design. Moreover, the effects of IPC on minority children are not well understood. In this longitudinal study, parenting was examined as a mediator of the relation between increasing IPC and change in depression. General cognitive style was included as a moderator. The combined influence of parenting and cognitions was also explored. A racially and ethnically diverse sample of 88 fifth and sixth graders from two urban schools reported their cognitive style, depressive symptoms, and perceptions of conflict and parenting at two time points separated by one year. Parental warmth/rejection mediated the relation between IPC and depression, and general cognitive style acted as a moderator. Parenting, cognitive style, and IPC did not significantly interact to predict change in depression over time. Findings indicate that both parenting and children’s general cognitive style play a role in understanding the impact of increasing IPC on children’s well-being.  相似文献   
69.
This essay investigates the political economy of sexuality through an interpretation of sex shows for foreigners in Bangkok, Thailand. Reading these performances as both symptoms of, and analytical commentaries on, Western consumer desire, the essay suggests the ‘pussy shows’ parody the mass production that was a hallmark of Western masculine identity under Fordism. This reading makes a case for the erotic generativity of capitalism, illuminating how Western, post-Fordist political economy of the post-1970s generated demand for these erotic services in Asia and how Western, heterosexual masculine desire is integrated into global capitalist circuits.  相似文献   
70.
Organizational culture is widely considered to be one of the most significant factors in reforming and modernizing public administration and service delivery. This article documents the findings of a literature review of existing qualitative and quantitative instruments for the exploration of organizational culture. Seventy instruments are identified, of which 48 could be submitted to psychometric assessment. The majority of these are at a preliminary stage of development. The study's conclusion is that there is no ideal instrument for cultural exploration. The degree to which any measure is seen as "fit for purpose" depends on the particular reason for which it is to be used and the context within which it is to be applied.  相似文献   
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