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61.
A method based on profiling of dye components by electrospray ionization mass spectrometry (ESI/MS) is described for the characterization of ballpoint pen inks. The method involves benzyl alcohol (30 microL) extraction of ink from paper. The extracts of ink lines 1 and 5 mm in length are used for direct ESI/MS analysis in positive and negative modes, respectively. The instrumental analysis takes 3 min. Basic and acid dyes in the inks are detected in the positive and negative modes, respectively, with each dye yielding one or two characteristic ion peaks. The mass spectrum, which is mainly a compositional signature of the dyes in the ink, was not affected by the type of paper from which the ink was extracted, or by natural ageing of the ink on document in the absence of light. However, exposure to fluorescent illumination caused dealkylation of polyalkylated basic dyes and resulted in changes in the homologous distribution of the dyes. In this study, a total of 44 blue inks, 23 black inks, and 10 red inks have been analyzed, and the mass spectra were used to establish a searchable library. ESI/MS analysis provides a simple and fast way to compare ink specimens and in combination with on-line library search permits rapid screening of inks for forensic document investigations.  相似文献   
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Self-determination theory (SDT) distinguishes between autonomous and controlled reasons for people’s behavior and essentially states that beneficial effects for individuals’ psychosocial adjustment will accrue when behavior is guided by autonomous (rather than controlled) motives. The present study tested this assumption in the area of adolescents’ identity styles. In a sample of mid-adolescents (N = 247; 53% female), it was found that the motives for using an information-oriented or a normative identity style explained additional variance beyond the identity styles as such in two of the adjustment outcomes examined. Specifically, autonomous motives underlying these two identity styles were positively related to commitment and personal well-being, whereas controlled motives were negatively related to these same adjustment outcomes. Perceived autonomy-supportive parenting was examined as a possible antecedent of the motives behind identity styles. Consistent with hypotheses, it was found that autonomy-supportive parenting was positively related to autonomous motives and negatively to controlled motives underlying identity styles. Implications for future research on the motivational dynamics behind identity development are discussed.  相似文献   
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Hundreds of transnational private governance organizations (TPGOs) have emerged in recent decades to govern social and environmental conditions of production using voluntary standards. A debate persists over whether the ties among different TPGOs and other organizations create a professional community that affects the behavior of TPGOs. To help resolve this debate, we analyze multiple ties among agriculture TPGOs to offer a more robust exploration of community structures and their potential effects for three forms of TPGO behavior – coordination, collaboration, and isomorphism. Our aggregate measure of ties reveals a thin community dominated by older TPGOs and TPGOs advancing a broad notion of sustainability that were created by Solidaridad, the World Wildlife Fund, and/or Unilever. The clearest community structures are built from ties that exhibit the potential for not actual collaboration, coordination, and isomorphism. Thus, while there exists convergence toward an emergent TPGO‐community, obstacles remain to more intense behavioral effects for TPGOs.  相似文献   
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This article attempts to understand how control over land (power in practice) is built, achieved and contested in the context of land transfers involving pressures over possession rights in Santiago del Estero in northern Argentina. Here new forms of land control – due to expansion of the speculative, soy and cattle frontiers – are changing and involve new relationships while using novel mechanisms to gain and maintain control. The article adopts the notion of shifting ‘frontiers of land control’ as an analytical lens, following Lund and Peluso (2011). We can say that the process of soy and cattle expansion into the new frontiers happens through a group of different mechanisms which range from voluntary purchase to violent evictions. As shifts in land control in the frontier involve pressures on possession rights, we observe different mechanisms of control, mainly in the direction of dispossession and enclosure. The paper adds to the debate on ‘land grabbing’ by (a) showing how domestic investors operate to advance industrial agriculture and (b) showing how this frontier advances in a context of (rather unsecured) possession rights where rights are being shifted through transfers (sales, leases, evictions) and compensation mechanisms as well as conflict and judicial procedures.  相似文献   
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Changes in personality traits in late adolescence and young adulthood are believed to co-occur with changes in identity, but little research is available that supports this hypothesis. The present study addressed this relatively understudied area of research by examining longitudinal associations of Big Five personality traits (i.e., Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness) with dimensions of identity formation (i.e., identification with commitment and exploration in depth) in the domain of education. For this purpose, we used four annual waves of longitudinal data on 485 Belgian late adolescents (87.4% female; mean age at T1 = 18.6 years) covering a 3-year period. Multivariate growth models revealed that changes in Big Five personality traits were related to changes in identification with commitment and exploration in depth. Cross-lagged panel models uncovered that, except for Openness, all Big Five traits predicted educational identity dimensions. Educational identity dimensions only predicted Neuroticism. In addition, adolescents with higher levels on the personality trait of Conscientiousness faced fewer study delays. In sum, the present study adds to the growing literature that explores the antecedents, correlates, and consequences of personality trait development by uncovering the interplay of personality traits, educational identity dimensions, and academic progress in late adolescents.  相似文献   
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Based on current theories of depression, reciprocal links between loneliness and depressive symptoms are expected to occur. However, longitudinal studies on adolescent samples are scarce and have yielded conflicting results. The present five-wave longitudinal study from mid- to late adolescence (N=428, M age at T1=15.22 years; 47% female) examined the direction of effect between loneliness and depressive symptoms, using cross-lagged path analysis. In addition, the robustness of these prospective associations was tested by examining the role of the Big Five personality traits (i.e., extraversion, conscientiousness, agreeableness, neuroticism, and openness) as explaining factors and moderators. Results indicated that loneliness and depressive symptoms influenced one another reciprocally, and these reciprocal associations were not attributable to their mutual overlap with personality traits. In addition, neuroticism was found to be a moderator, in that the bidirectional effects between loneliness and depressive symptoms were only found in adolescents high in neuroticism. Practical implications are discussed, and suggestions for future research are outlined.  相似文献   
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Journal of Youth and Adolescence - Over the last few years, the protective role of parental monitoring on adolescent adjustment (i.e., active parental efforts aimed at setting limits and tracking...  相似文献   
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Until recently, smallholder farmers in the Transkei area had very limited access to a profitable market outlet for their wool. In response, the South African wool industry built shearing sheds, managed by a local association that sells directly to the brokers. This article investigates the effect of joint wool marketing through the shearing shed on the farmers' revenue from wool. A three-step regression model of the revenue from wool indicates that the farmers selling through the shearing shed obtain better financial results as compared to those who use alternative channels. This analysis shows how new institutional arrangements may contribute to economic development.  相似文献   
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