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61.
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.  相似文献   
62.
The nations of the world are generally shaped by a cultural diversity, which must be preserved. This leads to a fundamental and essential defense of indigenous groups and their human rights. The purpose of this article is to highlight the importance of defending human rights of indigenous cucapa, natives settled in the northeast of the state of Baja California in the Delta of the Colorado River, especially with regards to their fishing rights, which is their main source of food and survival. The environmental laws that have been issued in the country have greatly affected them, banning commercial fishing in some areas and totally in many other areas, adding to that a not to subtle performance by the appropriate regulation authorities, preventing them from fishing sea bass, hence their consumption and marketing, which is reflected in their socioeconomic status. For this reason and in response to this violation of their human rights, women have decided to enter a cucapa womb strike, which threatens the existence of the tribe by not reproducing.  相似文献   
63.
Traditional methods for bone pulverization typically generate heat, risking stability of DNA sample. SPEX? has developed cryogenic grinders which introduce liquid nitrogen to cool the sample and aid in the grinding process. In this study, the Freezer Mill 6970 EFM was used with two DNA extraction methods and routine downstream STR analysis procedures. DNA from as little as 0.1 g of bone powder was used to develop full STR profiles after freezer mill pulverization, and the method was reproducible. Further, no contamination was detected upon cleaning/reuse of the sample vials. There were no significant differences in DNA yield, STR alleles detected, or peak heights using the freezer mill as compared to traditional grinding, and successful DNA profiles were achieved from as low as 0.1 g of bone powder with this method. Overall, this work indicates that this cryogenic mill method may be used as a viable alternative to traditional tissue grinders.  相似文献   
64.
This study aimed to develop and to assess an algorithm to facilitate lip print visualization, and to digitally analyze lip prints on different supports, by superimposition. It also aimed to classify lip prints according to sex. A batch image processing algorithm was developed, which facilitated the identification and extraction of information about lip grooves. However, it performed better for lip print images with a uniform background. Paper and glass slab allowed more correct identifications than glass and the both sides of compact disks. There was no significant difference between the type of support and the amount of matching structures located in the middle area of the lower lip. There was no evidence of association between types of lip grooves and sex. Lip groove patterns of type III and type I were the most common for both sexes. The development of systems for lip print analysis is necessary, mainly concerning digital methods.  相似文献   
65.
66.
The population grows and ages. Older adults, which is the group of people sixty years of age and older, increasingly represents a numerically larger group. Therefore, the legal rules are issued, and must be of such a nature that adequately protects them. In particular labor standards in Mexico, containing general provisions, but are emissive in relation to work of older adults subordinate.  相似文献   
67.
Stephen Dovers (ed.): Australian Environmental History: Essays and Cases . Melbourne: Oxford University Press, 1994.

Tim Flannery: The Future Eaters: An Ecological History of Australasian Lands and People . Chatswood, NSW: Reed Books, 1994. Distributed in the USA by George Braziller Inc., New York.

Stephen J. Pyne: Burning Bush: A Fire History of Australia , New York: Henry Holt, 1991.  相似文献   
68.
ABSTRACT

The usefulness of performance indicators increases when organizations compare their data. However, most discussions have failed to emphasize two lines of action that could improve the relevance of such comparisons: a) agreement among service managers on the indicators to be used in the evaluation; b) homogenization of the indicators to be used by organizations, and of the process used to calculate them. In this context, this paper proposes a methodology based on the participation of and consensus among managers, which helps to standardize the construction and presentation of performance indicators. The aim of this proposal is to improve the comparative evaluation of organizations. Finally, in order to test the proposal, a practical application is carried out on the local culture departments of nine large municipalities in southern Spain.  相似文献   
69.
ABSTRACT

The search for enhanced transparency and accountability in government organizations has inspired studies to identify the key factors that facilitate greater disclosure of public financial information. With the advantages provided by the meta-analysis technique, applied to a sample of studies, we identify the most significant factors and incentives underlying the decisions adopted by public managers on policy strategies regarding information transparency and public responsibility. Our study shows the variables analyzed to be positively associated with the disclosure of public financial information, but also that this depends on the context in which the research is carried out. The most influential variables were the moderator variables of the administrative culture and of the measurement unit for the variables.  相似文献   
70.
This review article offers a critical assessment of Ato Quayson's Cambridge History of Postcolonial Literature (2012), engaging in passing with a debate between postcolonial theorists that appeared also in 2012 in the New Literary History (43.1 & 2). It posits that the History presents postcolonial literature, and indeed postcolonial studies, as much too settled fields, a view clearly at odds both with their genesis and with that reflected in the essays in NLH.  相似文献   
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