376 research outputs found

    A Longitudinal Analysis of Volunteerism Activities for Individuals Educated in Public and Private Schools

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    Previous studies offer evidence that U.S. public and private high schools differentially influence volunteerism in adolescence. However, these studies are typically cross-sectional and only consider whether the individual volunteered or not. We address patterns of volunteering from adolescence into adulthood and the kind of volunteering activity in which individuals engage. We also theorize that distinctive civic values within public and private schools together with their respective organizational ties to other civic organizations channel students into particular volunteering activities. Relying on a longitudinal, nationally-representative sample of U.S. adolescents, we track volunteering from adolescence into young adulthood and identify the types of volunteering activities in which respondents engage. Results demonstrate that the likelihood of volunteering changes through the life course, and students from different schooling backgrounds systematically sort into specific volunteering activities as our theories predict

    E-Cadherin mediates UVR- and calcium-induced melanin transfer in human skin cells

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    yesSkin pigmentation is directed by epidermal-melanin units, characterized by long-lived and dendritic epidermal melanocytes (MC) that interact with viable keratinocytes (KC) to contribute melanin to the epidermis. Previously we reported that MC:KC contact is required for melanosome transfer, that this can be enhanced by filopodial and by UVR/UVA irradiation, which can up-regulate melanosome transfer via Myosin X-mediated control of MC filopodia. Both MC and KC express Ca2+-dependent E-cadherins. These homophilic adhesion contacts induce transient increases in intra-KC Ca2+, while ultraviolet radiation (UVR) raises intra-MC Ca2+ via calcium selective ORAI1 ion channels; both are associated with regulating melanogenesis. However, how Ca2+ triggers melanin transfer remains unclear, and here we evaluated the role of E-Cadherin in UVR-mediated melanin transfer in human skin cells. MC and KC in human epidermis variably express filopodia-associated E-Cadherin, Cdc42, VASP and β-catenin, all of which were upregulated by UVR/UVA in human MC in vitro. Knockdown of E-cadherin revealed that this cadherin is essential for UVR-induced MC filopodia formation and melanin transfer. Moreover, Ca2+ induced a dose-dependent increase in filopodia formation and melanin transfer, as well as increased β-catenin, Cdc42, Myosin X, and E-Cadherin expression in these skin cells. Together these data suggest that filopodial proteins and E-Cadherin, which are upregulated by intracellular (UVR-stimulated) and extracellular Ca2+ availability, are required for filopodia formation and melanin transfer. This may open new avenues to explore how Ca2+ signalling influences human pigmentation

    Biochemical and aggregation analysis of Bence Jones proteins from different light chain diseases

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    Deposition of immunoglobulin light chains is a result of clonal proliferation of monoclonal plasma cells that secrete free immunoglobulin light chains, also called Bence Jones proteins (Bence Jones proteins). These Bence Jones proteins are present in circulation in large amounts and excreted in urine in various light chain diseases such as light chain amyloidosis (AL), light chain deposition disease (LCDD) and multiple myeloma (MM). BJP from patients with AL, LCDD and MM were purified from their urine and studies were performed to determine their secondary structure, thermodynamic stability and aggregate formation kinetics. Our results show that LCDD and MM proteins have the lowest free energy of folding while all proteins show similar melting temperatures. Incubation of the BJP at their melting temperature produced morphologically different aggregates: amyloid fibrils from the AL proteins, amorphous aggregates from the LCDD proteins and large spherical species from the MM proteins. The aggregates formed under in vitro conditions suggested that the various proteins derived from patients with different light chain diseases might follow different aggregation pathways

    In Vitro Aggregation Behavior of a Non-Amyloidogenic λ Light Chain Dimer Deriving from U266 Multiple Myeloma Cells

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    Excessive production of monoclonal light chains due to multiple myeloma can induce aggregation-related disorders, such as light chain amyloidosis (AL) and light chain deposition diseases (LCDD). In this work, we produce a non-amyloidogenic IgE λ light chain dimer from human mammalian cells U266, which originated from a patient suffering from multiple myeloma, and we investigate the effect of several physicochemical parameters on the in vitro stability of this protein. The dimer is stable in physiological conditions and aggregation is observed only when strong denaturating conditions are applied (acidic pH with salt at large concentration or heating at melting temperature Tm at pH 7.4). The produced aggregates are spherical, amorphous oligomers. Despite the larger β-sheet content of such oligomers with respect to the native state, they do not bind Congo Red or ThT. The impossibility to obtain fibrils from the light chain dimer suggests that the occurrence of amyloidosis in patients requires the presence of the light chain fragment in the monomer form, while dimer can form only amorphous oligomers or amorphous deposits. No aggregation is observed after denaturant addition at pH 7.4 or at pH 2.0 with low salt concentration, indicating that not a generic unfolding but specific conformational changes are necessary to trigger aggregation. A specific anion effect in increasing the aggregation rate at pH 2.0 is observed according to the following order: SO4−≫Cl−>H2PO4−, confirming the peculiar role of sulfate in promoting protein aggregation. It is found that, at least for the investigated case, the mechanism of the sulfate effect is related to protein secondary structure changes induced by anion binding

    How do religious norms diffuse? Institutional translation and international change in a post-secular world society

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    This article draws from Habermasian post-secular theory to broaden the scope of Constructivist research on norm dynamics beyond its current Western-centric focus. In an increasingly post-secular world society, we conceptualize the mechanism of institutional translation to explain processes of norm diffusion whereby culturally situated ‘thick’ norms acquire a ‘thinner’ ethical status via a dialogical process of normative contestation across diverse ethical perspectives. Institutional translation differs from, but also complements, mechanisms of norm diffusion, such as persuasion and localization, by illustrating how norms conceived and promoted by non-Western religious-based actors can acquire global legitimacy within the institutions of the international liberal order. The article investigates the explanatory value of this framework through an empirical analysis of two contrasting cases of norm promotion by the Organization of Islamic Conference at the United Nations. The first case considers the global diffusion of the norm of dialogue of civilizations as an example of successful institutional translation. The second case illustrates the failed diffusion of the norm against th

    Correlations, Causes and the Logic of Obscuration: Donor Shaping of Dominant Narratives in Indonesia's Irrigation Development

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    This article analyses policy trends in Indonesian irrigation, particularly during the last five decades, from the perspective of dominant narratives, as authored, suggested and pushed by international donors. It argues that international donors' adherence to ‘deferred maintenance’ as the core element of irrigation policy problem framing does not match with farmers' and the irrigation agency staff perceptions and practices. The logic of obscuration and the discursive manoeuvers that maintain it are analysed. The article concludes that there is space for more profound conceptual contestation and for alternative actions pathways even within the ‘dominant paradigm’ to address management problems more effectively

    Comparison of health conditions treated with traditional and biomedical health care in a Quechua community in rural Bolivia

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    <p>Abstract</p> <p>Background</p> <p>The objective of the present study was to reveal patterns in the treatment of health conditions in a Quechua-speaking community in the Bolivian Andes based on plant use data from traditional healers and patient data from a primary health care (PHC) service, and to demonstrate similarities and differences between the type of illnesses treated with traditional and biomedical health care, respectively.</p> <p>Methods</p> <p>A secondary analysis of plant use data from semi-structured interviews with eight healers was conducted and diagnostic data was collected from 324 patients in the community PHC service. Health conditions were ranked according to: (A) the percentage of patients in the PHC service diagnosed with these conditions; and (B) the citation frequency of plant use reports to treat these conditions by healers. Healers were also queried about the payment modalities they offer to their patients.</p> <p>Results</p> <p>Plant use reports from healers yielded 1166 responses about 181 medicinal plant species, which are used to treat 67 different health conditions, ranging from general symptoms (e.g. fever and body pain), to more specific ailments, such as arthritis, biliary colic and pneumonia. The results show that treatment offered by traditional medicine overlaps with biomedical health care in the case of respiratory infections, wounds and bruises, fever and biliary colic/cholecystitis. Furthermore, traditional health care appears to be complementary to biomedical health care for chronic illnesses, especially arthritis, and for folk illnesses that are particularly relevant within the local cultural context. Payment from patients to healers included flexible, outcome contingent and non-monetary options.</p> <p>Conclusion</p> <p>Traditional medicine in the study area is adaptive because it corresponds well with local patterns of morbidity, health care needs in relation to chronic illnesses, cultural perceptions of health conditions and socio-economic aspects of health care. The quantitative analysis of plant use reports and patient data represents a novel approach to compare the contribution of traditional and biomedical health care to treatment of particular health conditions.</p
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