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1.
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   
2.
Few cases of natural sudden death presenting as an undiagnosed lymphoma have been reported in the literature, especially in adolescents. Herein we provide a report of sudden death caused by undiagnosed classic Hodgkin lymphoma (cHL). We describe an 18-year-old female who collapsed after several weeks of weight loss, decreased appetite, and dyspnea. At autopsy, a bulky mass arising in the mediastinum and neck compressed the esophagus and trachea, surrounded the great vessels, obliterated the pericardial sac, and infiltrated the myocardium. The lungs were collapsed and large pleural effusions were present. The tumor burden, which weighed at least 2710 g in aggregate, was entirely above the diaphragm. Microscopic examination of the masses showed features typical for nodular sclerosis cHL including large bands of sclerosis, numerous Hodgkin/Reed-Sternberg (HRS) cells, and an eosinophil-rich mixed inflammatory cell infiltrate. Immunohistochemical stains showed the HRS cells to be uniformly positive for CD30 and CD15 and negative for CD3, CD20, CD45, and PAX5. This case exemplifies a rare sudden natural death due to previously undiagnosed cHL in a young patient.  相似文献   
3.
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations.  相似文献   
4.
Amidst calls for more scrutiny of the failure of infrastructure public–private partnerships (PPPs), uncertainty about how we can measure failure remains, and little systematic evidence illuminates its likelihood. Our mixed‐methods design explores the notion of failure and identifies the conditions under which it happens. The first phase of our research employs documentary analysis and semistructured expert interviews, and identifies project cancellation as capturing the most severe occurrences of failure. A second phase statistically analyzes a unique World Bank data set capturing the provisions of over 4,000 infrastructure PPPs launched between 1990 and 2015 in 89 countries. We find robust evidence supporting the theoretical claim that PPPs are less likely to be canceled in countries with more veto points among their political institutions to restrain politicians from intervening in policy implementation. Cancellation is a rare, but valid indicator of failure, and the importance of veto players clarifies how political risk operates in this context.  相似文献   
5.

China’s rise as a global power corresponded with a diminution of Taiwanese diplomacy, which has left Central America as the last region to host a continuous bloc of countries that recognize the ROC. In this article, we argue that China’s success in gaining diplomatic recognition from Taiwan’s former allies has largely resulted from China's economic policy, specifically its promises of large-scale infrastructure projects and the integration of Central American economies with Chinese markets. However, there are limits to how far China has advanced in gaining full recognition from the region. The competing political and economic interests of China, Taiwan, the United States, and the Central American countries themselves, continue to influence patterns of diplomatic switching. More specifically, we argue that the threat of punitive measures from the United States combined with a turn in Taiwanese diplomacy toward assistance efforts to combat Covid-19 may deter future switching in the short to medium-term. Our analysis offers case studies of four Central American countries (Costa Rica, Panama, El Salvador and Nicaragua) to illustrate the multi-year processes by which China’s economic strategy leads to diplomatic switching and examine the paths ahead for the remaining holdouts facing the prospect of economic and political penalties by the United States.

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6.
An extensive body of research documents how governing parties generally suffer electoral defeats. Varying explanations have been offered, most of which touch upon the liabilities of policy responsibility. Although media coverage is generally acknowledged as one of these liabilities, few empirical studies have examined how news content affect government support. Based on the fact that voters get their information about politics, policies and societal issues from the media, this article studies how the constant stream of negative news influences incumbent support over a 20-year period in Denmark. Modeling a previously untested argument on the cost of ruling, it shows that the accumulation of bad news throughout tenure exerts a substantial effect on government support.  相似文献   
7.

There is strong evidence that chronic, systemic inflammation hastens onset of the diseases of old age that ultimately lead to death. Importantly, several studies suggest that childhood adversity predicts chronic inflammation. Unfortunately, this research has been plagued by retrospective reports of childhood adversity, an absence of controls for adult stressors, and a failure to investigate various competing models of the link between childhood adversity and chronic inflammation. The present study was designed to address these limitations. Using 18 years of data collected from 413 African Americans (58% female) included in the Family and Community Health Study, hierarchical regression analyses provided support for a nuanced early life sensitivity explanation for the link between early adversity and adult chronic inflammation. Controlling for health risk behaviors and adult SES, late childhood (ages 10–12) adversity amplified the association between adult adversity (age 29) and chronic inflammation. This interaction operated in a domain-specific fashion. Harsh parenting amplified the relation between intimate partner hostility and inflammation, whereas early discrimination amplified the relation between adult discrimination and inflammation. These findings suggest that individuals may be primed to respond physiologically to adverse adult circumstances that resemble those experienced earlier in life.

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8.
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.  相似文献   
9.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined.  相似文献   
10.
This study is the first to examine the background level of male DNA on underpants worn by females in the absence of sexual contact. Here, we examined 103 samples from the inside front of underpants from 85 female volunteers. Samples were examined for the presence of male DNA using NGM SElect and PowerPlex Y23 kits. Only five samples gave a “complete” Y-STR profile, even though 83.5% of our volunteers cohabited with a male. In all cases where a partner reference sample was available, the Y-STR profile matched the cohabiting partner. We have demonstrated that a Y-STR profile is not expected on the inside front of underpants worn by females after social contact alone. The results of this study are informative for evaluating the significance of a Y-STR profile on underpants in cases of alleged sexual assault.  相似文献   
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