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111.
The preservation of teeth that have been exposed to a heat source is a key factor in order to keep their value as evidence. This research paper presents some methods under development for the analysis of dental evidence after exposure to high temperatures; it also establishes age related alterations of young and aged teeth which have been exposed to direct heat. A total of thirty permanent healthy teeth (young=15 and old=15) were submitted to direct heat (n=14) and to a controlled raise of temperature (n=16); they were embedded in polymethylmetacrilate. For the macroscopic study, blocks were cut in half, polished and their surfaces were digitalized. Subsequently, blocks were put in slides, worn away and observed through a photomicroscope. The study of the colorimetric pattern was done by Corel Photo Paint 12.0 and Image J. software. All teeth submitted to the gradual raise of temperature presented a degree of structural damage lower than those exposed to direct heat. The internal surface of young teeth exposed to direct heat showed lines of fracture oblique to the long axis of the tooth; in contrast, a reticular pattern was observed on aged teeth. All teeth exposed to direct heat showed some matte-black coloration areas, while those submitted to a gradual increment of temperature showed a greyish colour in the enamel and a chalky-white in the cementum. By using both thermal treatments in young teeth, the amelodentinal junction was lost, thus preserving the integrity of each tissue. In aged teeth, the separation of this junction was produced because of the breakdown of the dentine. Microscopically, in teeth exposed to direct heat, it was neither possible to differentiate the dentin from the cementum, nor to distinguish the incremental lines of the latter; while in those submitted to a controlled increment of temperature, the corresponding morphology in the tissues was observed. A significant statistical difference was obtained for black colour among young and aged teeth exposed to direct heat, as well as among the means of all colours obtained from the teeth exposed to both treatments. The structural changes observed allow locating a tooth in the studied age groups. Our results show the viability of the applied method for the processing of samples, allowing their preservation as evidence during an indefinite time.  相似文献   
112.
Recent scholarship on transnational business governance has begun to examine public-private interactions and the active role of governments. We make two key contributions that integrate and expand this literature. First, in juxtaposition to functionalist accounts, we foreground the fundamentally political and often contentious character of these interactions. As private transnational governance schemes and standards “hit the ground,” private-public interactions, we argue, are embedded in national political arenas and tied to domestic distributional struggles among competing regulatory coalitions. Building upon multiple empirical streams of research, we develop a political-strategic framework that maps the diversity of Southern government responses (substitute, adopt, repurpose, replace, or reject) to transnational private governance. Our framework shows that government responses are a function of both strategic fit with domestic industrial capabilities and structures, and strength of developmental state capacity. Second, our proposed framework adopts the vantage point of Global South governments and industries, particularly how development challenges and strategic options within global value chains affect their understanding of, and responses to, transnational schemes and standards. This is an important corrective to a Northern bias in the private governance literature.  相似文献   
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114.
Provisions for a parliamentary investiture vote have become increasingly common in parliamentary democracies. This article shows that investiture provisions were largely introduced when new constitutions were written or old ones fundamentally redesigned. It also shows that the constitutions that endowed executives with strong legislative agenda powers also endowed parliaments with strong mechanisms to select the executive. It is argued that constitution makers’ decisions can be seen in principal–agent terms: strong investiture rules constitute an ex ante mechanism of parliamentary control – that is, a mechanism to minimise adverse selection and reduce the risk of agency loss by parliament. The findings have two broad implications: from a constitutional point of view, parliamentary systems do not rely exclusively on ex post control mechanisms such as the no confidence vote to minimise agency loss; parliamentarism, at least today and as much as presidentialism, is the product of conscious constitutional design and not evolutionary adaptation.  相似文献   
115.
Psychological distress has been inconsistently associated with sexual risk behavior in youth, suggesting additional factors, such as substance use, may explain this relationship. The mediating or moderating role of substance use on the relationship between psychological distress and sexual risk behaviors was prospectively examined over the four high school years in a sample of urban youth (N = 850; 80% African American; 50% female). Growth curve modeling was used to estimate changes in sexual risk across adolescence and to test its association to psychological distress symptoms and frequency of substance use. Substance use was associated with psychological distress. Greater psychological distress was associated with increased sexual intercourse frequency, decreased condom use, and increased number of partners. Substance use fully mediated the relationship between psychological distress and intercourse frequency and condom use, and partially mediated the relationship between psychological distress and number of partners. We found no differences in mediation by sex or race/ethnicity and no evidence to support moderation of psychological distress and substance use on sexual risk. Findings suggest that psychological distress is associated with sexual risk because youth with greater psychological distress are also more likely to use substances. Practical implications for adolescent HIV/STI prevention are discussed.  相似文献   
116.
Although the recognition of the adoptive rights of LGBT (lesbian, gay, bisexual, and transgender) couples is a socially salient topic, cross-national variation regarding this issue has been largely underexplored in social science research. With the aid of configurational analysis, this article fills this gap and shows the conditions that explain the recognition of the adoptive rights of homosexual couples in the countries of the EU-27. It is argued that two different paths led to this outcome. All countries where adoptive rights were recognized had higher degrees of secularization and lower levels of social homophobia. In addition, in Northern European countries, the Protestant background and absence of conservative governments for a certain time period seemed to be the determinant. However, for the remaining European countries that recognized these rights, rising levels of gender equality appeared to have a more salient role.  相似文献   
117.
Scholars have long explored why presidential rhetoric is important and how it matters for public leadership and policy-making. However, relatively few works have considered the role that emotion plays in leadership communication and no research has conducted a thorough examination of the various types of emotions invoked in presidential rhetoric, their frequency, or how they have shaped presidential discourse over time. In this study, presidential speeches across 13 administrations (1933–2011) are examined to provide a first assessment of the extent to which US presidents have invoked fear, anger, and hope across policy domains and key types of speeches.  相似文献   
118.
This article considers the influential work of Ana Mendieta. Focusing on her siluetas series, Muñoz describes Mendieta's art as performing a modality of brownness that leaves resonant indentions on the world, what he calls vital materialist after-burns. Mendieta's after-burns are read alongside the poet's of Négritude and their investment in a critical élan vital that speaks to the historical precariousness of dispossessed people. The artist's work is explained as a meditation on a critical brownness that is theorized as the sharing out of the unshareable, the invaluable and the incalculable.?Mendieta's intervention is ultimately described as the work of offering a brown sense of the world in which singularities flow into a politically enabling common.  相似文献   
119.
Abstract

According to international relations scholars, an important change taking place in the post-Cold War context concerns the lethality of non-state armed groups (NSAGs). Underlying this observation is the conventional assumption that non-state violence is intrinsically illegitimate. This article shifts the analysis of violence away from the terrain of legitimacy, which tends to moralise the difference between state and non-state forces, and towards the terrain of work, where their violence features as part and not separate from a shared political economy. I propose the notion of violence work as a resourceful analytic into the dialectics of everyday violence and the complex processes of value production in social life. Against the background of the extreme cruelty attributed to transnational gangs in Central America, I argue that their violence work is expressive of prevailing modes of accumulating wealth in the region. Drawing on multi-sited fieldwork in Honduras, Guatemala, El Salvador and Mexico, I show how gang violence work animates a system of economic cooperation that engages a wide array of subjects who traverse state/non-state and legal/illegal divides.  相似文献   
120.
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