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261.
Existing research rarely considers important ethnic subgroup variations in violent behaviors among Latino youth. Thus, their risk for severe violent behaviors is not well understood in light of the immense ethnic and generational diversity of the Latino population in the United States. Grounded in social control theory and cultural analyses of familism, we examine differences in the risk for severe youth violence, as well its associations with family cohesion, parental engagement, adolescent autonomy, household composition, and immigrant generation among Mexican (n = 1,594), Puerto Rican (n = 586), Cuban (n = 488), and non-Latino Black (n = 4,053), and White (n = 9,921) adolescents with data from the National Longitudinal Study of Adolescent Health. Results indicate a gradient of risk; White youth had the lowest risk for severe violence and Puerto Rican youth had the highest risk compared to all other racial/ethnic subgroups. Within-group analysis indicates that family factors are not universally protective or risk-inducing. While family cohesion decreased the risk of severe violence among all groups, parental engagement was associated with increased risk among Blacks and Whites, and adolescent autonomy was associated with increased risk among Puerto Ricans and Cubans. In addition, Cuban and White adolescents who lived in single parent households or who did not live with their parents, had higher risk for severe violent behaviors than their counterparts who lived in two parent households. Among Latinos, the association of immigrant generation was in opposite directions among Mexicans and Cubans. We conclude that family and immigration factors differentially influence risk for violence among Latino subgroups and highlight the significance of examining subgroup differences and developing intervention strategies that are tailored to the needs of each ethnic subgroup.  相似文献   
262.
The three Rio Conventions—the United Nations Framework Convention on Climate Change, the Convention on Biological Diversity, and the United Nations Convention to Combat Desertification—face the challenge to create synergies at different levels. The objective of this article is to describe how we have assessed synergies between the Rio Conventions at the project level in the forest sector. Since the complexity of the decision problem is high, we adopted the Multicriteria Decision Aid approach, which can provide a broad insight into the decision problem and find a compromise solution to a problem with multidimensional and conflicting criteria including social, economic and environmental features. The ELECTRE TRI model was used for assessing synergies at the project level, and has been a useful tool to quantify the performance of afforestation and reforestation projects into three categories (synergistic, reasonably synergistic, and not synergistic). For the first time, afforestation and reforestation projects have been assessed in a comprehensive way through decision criteria that reflect global and local interests using a non-compensatory multicriteria method.  相似文献   
263.
Spectral analysis and ARMA models have been the most common weapons of choice for the detection of cycles in political time series. Controversies about cycles, however, tend to revolve around an issue that both techniques are badly equipped to address: the possibility of irregular cycles without fixed periodicity throughout the entire time series. This has led to two main consequences. On the one hand, proponents of cyclical theories have often dismissed established statistical techniques. On the other hand, proponents of established techniques have dismissed the possibility of cycles without fixed periodicity. Wavelets allow the detection of transient and coexisting cycles and structural breaks in periodicity. In this article, we present the tools of wavelet analysis and apply them to the study of two lingering puzzles in the political science literature: the existence of cycles in election returns in the United States and in the severity of major power wars.  相似文献   
264.
Using desorption/ionization techniques such as easy ambient sonic-spray ionization mass spectrometry (EASI-MS), it is possible to analyze documents of Brazilian vehicles for authenticity, providing a chemical profile directly from the surface of each document. A method for the detection of counterfeit documents is described, and the falsification procedure is elucidated. Forty authentic and counterfeit documents were analyzed by both positive and negative ion modes, EASI(±)-MS. EASI(+)-MS results identified the presence of (bis(2-ethylhexyl)phthalate plasticizer and of dihexadecyldimethylammonium biocide in both types of documents. For EASI(-)-MS results, the 4-octyloxybenzoic acid additive ([M + H](+): m/z 249) is present only in counterfeit documents. It was also found that counterfeit vehicle documents are produced via Laserjet printers. Desorption/ionization techniques, such as EASI-MS, offer therefore, an intelligent way to characterize the counterfeiting method.  相似文献   
265.
Recent information from various sources suggests that a new illicit drug, called "oxi", is being spread across Brazil. It would be used in the smoked form and it would look like to crack cocaine: usually small yellowish or light brown stones. As fully released in the media, "oxi" would differ from crack cocaine in the sense that crack would contain carbonate or bicarbonate salts whereas "oxi" would include the addition of calcium oxide and kerosene (or gasoline). In this context, this work presents a chemical profiling comparative study between "oxi" street samples seized by the Civil Police of the State of Acre (CP/AC) and samples associated with both international and interstate drug trafficking seized by the Brazilian Federal Police in Acre (FP/AC). The outcome of this work assisted Brazilian authorities to stop inaccurate and alarmist releases on this issue. It may be of good use by the forensic community in order to better understand matters in their efforts to guide local law enforcement agencies in case such claims reach the international illicit market.  相似文献   
266.
After the train bombing in Madrid (Spain) on 11 March 2004, methenamine was detected in some of the specimens of Goma-2 ECO dynamite submitted to the forensic laboratories when analyzed by gas chromatography coupled with mass spectrometry detection (GC-MS). Methenamine is synthesized from formaldehyde and ammonia through a condensation reaction. However, neither methenamine nor any of these compounds were used to manufacture Goma-2 ECO dynamite. Four different experiments were designed in order to explain the presence of methenamine detected in the dynamite samples analyzed. In the first one, GC-MS was used to analyze the individual components of Goma-2 ECO provided by the manufacturer and the components mixed in a raw paste. Methenamine was detected in the manufacturer's ammonium nitrate and in the raw paste. The other experiments were designed to find the precursors sources for methenamine generation in Goma-2 ECO. Results revealed that these sources could be ammonium nitrate for ammonia and sawdust for formaldehyde. Under heating conditions, dynamite could produce these precursors, which could condense in the injection port of the GC-MS system and generate methenamine. However, methenamine was not always detected in these dynamites. This was explained by the existence of two opposite effects: (a) dynamite stability makes difficult that ammonium nitrate releases ammonia and (b) there is a gradual loss of formaldehyde in sawdust along the time. Both effects can prevent the formation of an amount of methenamine large enough to be detected.  相似文献   
267.
The identification process of a mass grave from the Spanish Civil War (1936-1939) is presented. The presumed location of the grave, as well as the presumed number and identities of the persons buried in the grave were obtained exclusively from witnesses' and relatives' testimonies. In agreement with the testimonies, the grave was located at the indicated location and five skeletons were exhumed. Also in agreement with the testimonies, the osteological and DNA study led investigators to propose the identification of two kin groups, a father and his son and a pair of brothers. But the genetic study did not support the identification of a fifth man presumed to have been buried in the grave. The differences and similarities between this case and another case reported earlier are discussed.  相似文献   
268.
The purpose of this study is to clarify the chronology of different stages of dental development, according to Demirjian, in a sample of Spanish children, which will enable us to build a database that will be used as a reference in regard to the dental development of individuals of our socio-geographic environment. In the same studied sample, a calculation of the dental age according to Demirjian was carried out. This study was conducted in a final sample consisting of 1010 orthopantograms, corresponding to Spanish children (485 boys and 525 girls) ages 2-16. Comparing the age of onset of the different stages among the children, evidence was found that girls had an earlier general development than boys. These differences were only statistically significant in teeth and concrete stages. The canine teeth revealed greater gender dimorphism, with significant differences in all stages compared with the upper canines. The method proposed by Demirjian for dental age calculation resulted in a significant overestimation of dental age in relation to the chronological age in boys (average of 0.87 years) and girls (average of 0.55 years). Data from this study may be used as reference for dental maturity, as well as a standard for estimating age in Spanish children.  相似文献   
269.
In Germany, both the number of patients treated in forensic psychiatric hospitals and the average inpatient treatment period have been increasing for over thirty years. Biographical and clinical factors, e.g., the number of prior offences, type of offence, and psychiatric diagnosis, count among the factors that influence the treatment duration and the likelihood of discharge. The aims of the current study were threefold: (1) to provide an estimate of the German forensic psychiatric patient population with a low likelihood of discharge, (2) to replicate a set of personal variables that predict a relatively high, as opposed to a low, likelihood of discharge from forensic psychiatric hospitals, and (3) to describe a group of other factors that are likely to add to the existing body of knowledge. Based on a sample of 899 patients, we applied a battery of primarily biographical and other personal variables to two subgroups of patients. The first subgroup of patients had been treated in a forensic psychiatric hospital according to section 63 of the German legal code for at least ten years (long-stay patients, n=137), whereas the second subgroup had been released after a maximum treatment period of four years (short-stay patients, n=67). The resulting logistic regression model had a high goodness of fit, with more than 85% of the patients correctly classified into the groups. In accordance with earlier studies, we found a series of personal variables, including age at first admission and type of offence, to be predictive of a short or long-stay. Other findings, such as the high number of immigrants among the short-stay patients and the significance of a patient's work time before admission to a forensic psychiatric hospital, are more clearly represented than has been observed in previous research.  相似文献   
270.
In recent years, both scientific and judicial sources have highlighted the need for more knowledge about minutiae variability, in order to improve their statistical application to fingerprint identification. In line with this trend toward improving our knowledge of this subject, the aim of the present study was to calculate the frequency with which 20 types of minutiae appeared in 2780 fingerprint impressions obtained from 278 individuals from two Argentinian population samples (100 individuals from Ramal and 178 from Puna-Quebrada). The different types of minutiae were located, identified, and quantified visually in two areas on the fingerprint, the inside and outside of a circle, the radius of which cut fifteen ridges perpendicularly, starting from the center cut of the axes defining the sectors. The non-equiprobability found in both population samples for the different minutiae types studied demonstrated that the evidential weight provided by these characteristics is not the same when applied in identification processes, whether used quantitatively (numerical standard) or qualitatively (holistic method). The results obtained for both populations were compared statistically with those published previously for a Spanish population sample, which had been collected using the same methodology. This comparison has enabled us to demonstrate, for the first time, the existence of significant differences between populations in minutiae frequencies, independently from the main pattern type.  相似文献   
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