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101.
The 608-bp hypervariable region 1 (HV1) sequences from 36 local dogs were analyzed to characterize the population genetic structure of canid mitochondrial DNA (mtDNA). Sixteen haplotypes were identified. A 417-bp segment of this sequence was compared with GenBank sequences from a geographically representative sample of 201 dogs, two coyotes, and two wolves. Sixty-six haplotypes were identified including 62 found only in domestic dogs. Fourteen of these correspond to the 16 local haplotypes and were among the most frequent haplotypes. The local sample was judged to be representative of the much broader geographic sample. No correlation was observed between local haplotypes and the owner's characterization of dog breed. A 60-bp variation "hotspot" within the canid HV1 was identified as a potentially valuable molecular tool, particularly for assaying limited or degraded DNA samples.  相似文献   
102.
A series of validation experiments was performed for a Y chromosome specific STR multiplex system following the suggestions made by the Technical Working Group DNA Analysis Methods (TWGDAM). The multiplex PCR products were detected on Perkin-Elmer 373 and 377 automated sequencers using two labeling colors. No problems regarding the stability, robustness and sensitivity of the Y STR multiplex were observed. Mixture studies revealed a cut off rate similar to autosomal STRs for mixtures of male DNAs and no interference of any female admixture. The comparison of the Y STR results to the autosomal typing results for 56 nonprobative semen stains and swabs, showed a slightly higher success rate in detecting the semen donor’s alleles for the Y STR multiplex. Two examples are shown to illustrate the usefulness of Y STR typing for DNA mixtures. In one case the Y STR results confirmed an isolated exclusion; in the other case, the interpretation of a mixture was clarified since the Y STR results proved the presence of DNA from at least two semen donors. Y STR typing is a valuable addition to the forensic DNA testing panel.  相似文献   
103.
Chioqueta AP  Stiles TC 《危机》2007,28(2):67-73
In this study we examined the role of psychological buffers (life satisfaction, self-esteem, perception of family cohesion, and perception of social support) in the development of hopelessness and suicidal ideation. The participants were 314 university students, 71 males and 243 females, who were asked to complete a battery of instruments measuring the psychological buffers mentioned above. The results of a set of hierarchical multiple regression analyses suggested that life satisfaction and self-esteem are independent predictors of lower levels of hopelessness, while perception of social support seems to be the major predictor of lower levels of suicidal ideation independent of depression and hopelessness severity. Thus, hopelessness seems to be minimized by the level of life satisfaction and level of self-esteem exhibited by the individuals, while the key factor to the mitigation of suicidal ideas seems to be perception of social support.  相似文献   
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Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
106.
This paper explores the political field that has opened up in the wake of the recent civil war in Nepal. We focus on cultural-political developments in agrarian districts, where some of the most intriguing openings, and indeed the most pernicious closures, can be witnessed (as opposed to the national-state restructuring that commands more media and popular attention). Our research asks what spaces open up in the emerging political field at the district scale to entrench or transform dominant cultural codes and sedimented histories of socio-economic inequality. Preliminary research identifies specific sectors of local governance that have emerged as significant sites of struggle over the shape and meaning of ‘democracy’, namely forest management and infrastructure development. The primary contribution of the paper lies in specifying an analytical approach to the study of ‘post-conflict’ governance at the local scale via three conceptual terrains of inquiry – governance and planning, political subjectivity, and cultural politics. The ultimate objective is to develop a framework for assessing the conditions of possibility for a democratic restructuring of economy and society to accompany the official political institutions of liberal democracy.  相似文献   
107.
This paper analyses contrasting discourses of ‘climate-smart agriculture’ (CSA) for their implications on control over and access to changing resources in agriculture. One of the principal areas of contestation around CSA relates to equity, including who wins and who loses, who is able to participate, and whose knowledge and perspectives count in the process. Yet to date, the equity implications of CSA remain an under-researched area. We apply an equity framework centred on procedure, distribution and recognition, to four different discourses. Depending on which discourses are mobilised, the analysis helps to illuminate: (1) how CSA may transfer the burden of responsibility for climate change mitigation to marginalised producers and resource managers (distributive equity); (2) how CSA discourses generally fail to confront entrenched power relations that may constrain or block the emergence of more ‘pro-poor’ forms of agricultural development, adaptation to climate change, or carbon sequestration and storage (procedural equity); (3) how CSA discourses can have tangible implications for the bargaining power of the poorest and most vulnerable groups (recognition). The paper contributes to work showing the need for deeper acknowledgement of the political nature of the transformations necessary to address the challenges caused by a changing climate for the agricultural sector.  相似文献   
108.
Although activity involvement has been linked to positive youth development, the value that adolescents place on these activities (i.e., how much they enjoy the activities, find them important, and spend time on them) has received less attention. The purpose of the present study was to examine the bidirectional longitudinal association between engagement in valued activities and adolescent positive adjustment (optimism, purpose in life, and self-esteem), as well as investigate a possible underlying mechanism for this link. High school students (N = 2,270, 48.7 % female) from Ontario, Canada completed questionnaires annually in grades 10, 11, and 12. Auto-regressive cross-lagged path analyses were conducted over time, controlling for gender, parental education, and academic grades. Greater engagement in valued activities predicted higher optimism, purpose, and self-esteem over time. Importantly, the results did not support an alternate hypothesis of selection effects, in that adolescents who were better adjusted were not more likely than their peers to engage in valued activities over time. We also found that the longitudinal associations between valued activities and positive adjustment may be due partly to an underlying effect of increased positive mood. Thus, engagement in valued activities appears to be important for adolescent positive adjustment, and may help to foster thriving. Communities, educators, and parents should actively support and encourage adolescents to develop valued activities, and seek to ensure that there are ample opportunities and resources available for them to do so.  相似文献   
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This article demonstrates the analytical advantages of studying not only the degree to which people oppose immigration in a country, but also the character of their opposition. Using Latent Class Analysis and data from the European Social Survey, Nordic patterns and trends are examined with the aim of identifying different kinds of immigration attitudes and how they develop in different national contexts. The Nordic countries are interesting to compare as, while they are similar in many respects, they also diverge significantly from each other in areas theoretically considered important to the formation of attitudes towards immigration. Studying the character of immigration opposition reveals five different types of immigration attitudes. These are differently distributed between the Nordic countries as well as over time, and include nativist opposition (opposition only towards immigrants of ethnic/racial groups other than that of the majority population) and economic opposition (opposition that entails a separation between immigrants considered to be an economic resource and an economic burden). By demonstrating how immigration opposition in the Nordic countries varies not only in degree but also in character, the article contributes to a deeper understanding of the nature of immigration opposition as well as of how different attitudinal profiles evolve under different contextual circumstances.  相似文献   
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