936 research outputs found
ESR dating of a toxodon tooth from a Brazilian karstic cave
No full textA pre-molar of a Toxodon platensis (sp), a large mammal that inhabited the forests of Southeast Brazil during quaternary times, was dated by electron spin resonance (ESR). Enamel and dentine were separated giving the following archeological doses (AD): (4.0 ± 0.8) and (11 ± 2) Gy, respectively. This difference was explained by the higher content of Uranium in dentine (25.1 ± 0.3) ppm as compared to enamel (0.37 ± 0.03) ppm. Taking account of the internal dose contribution to the AD, the age obtained is (6.7 ± 1.3) ky BP for dentine and (5.0 ± 1.6) ky BP for enamel
Proteomic characterization of human LMNA-related congenital muscular dystrophy muscle cells
Get PDFLMNA-related congenital muscular dystrophy (L-CMD) is caused by mutations in the LMNA gene, encoding lamin A/C. To further understand the molecular mechanisms of L-CMD, proteomic profiling using DIA mass spectrometry was conducted on immortalized myoblasts and myotubes from controls and L-CMD donors each harbouring a different LMNA mutation (R249W, del.32 K and L380S). Compared to controls, 124 and 228 differentially abundant proteins were detected in L-CMD myoblasts and myotubes, respectively, and were associated with enriched canonical pathways including synaptogenesis and necroptosis in myoblasts, and Huntington's disease and insulin secretion in myotubes. Abnormal nuclear morphology and reduced lamin A/C and emerin abundance was evident in all L-CMD cell lines compared to controls, while nucleoplasmic aggregation of lamin A/C was restricted to del.32 K cells, and mislocalization of emerin was restricted to R249W cells. Abnormal nuclear morphology indicates loss of nuclear lamina integrity as a common feature of L-CMD, likely rendering muscle cells vulnerable to mechanically induced stress, while differences between L-CMD cell lines in emerin and lamin A localization suggests that some molecular alterations in L-CMD are mutation specific. Nonetheless, identifying common proteomic alterations and molecular pathways across all three L-CMD lines has highlighted potential targets for the development of non-mutation specific therapies. [Abstract copyright: Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.
Education Mitigates the Relationship of Stress and Mental Disorders Among Rural Indian Women
Get PDFCo-author Apurv Soni is a medical student at UMass Medical School.BACKGROUND: Common mental disorders (CMD) are a constellation of mental health conditions that include depression, anxiety, and other related nonpsychotic affective disorders. Qualitative explanatory models of mental health among reproductive-aged women in India reveal that distress is strongly associated with CMD. The relationship of perceived stress and CMD might be attenuated or exacerbated based on an individual's sociodemographic characteristics. OBJECTIVES: To screen for Common Mental Disorders (CMD) among reproductive-aged women from rural western India and explore how the relationship between perceived stress and CMD screening status varies by sociodemographic characteristics. METHODS: Cross-sectional survey of 700 women from rural Gujarat, India. CMD screening status was assessed using Self-Reported Questionnaire 20 (SRQ-20). Factors associated with CMD screening status were evaluated using multivariable logistic regression. Effect modification for the relationship of perceived stress and CMD screening status was assessed using interaction terms and interpreted in terms of predicted probabilities. FINDINGS: The analytic cohort included 663 women, with roughly 1 in 4 screening positive for CMD (157, 23.7%). Poor income, low education, food insecurity, and recurrent thoughts after traumatic events were associated with increased risk of positive CMD screen. Perceived stress was closely associated with CMD screening status. Higher education attenuated the relationship between high levels of stress and CMD screening status (82.3%, 88.8%, 32.9%; P value for trend: 0.03). Increasing income and age attenuated the link between moderate stress and CMD. CONCLUSIONS: Our findings suggest a high burden of possible CMD among reproductive-aged women from rural western India. Higher education might mitigate the association between elevated stress and CMD. Future efforts to improve mental health in rural India should focus on preventing CMD by enhancing rural women's self-efficacy and problem-solving capabilities to overcome challenging life events and stressors, thereby reducing the risk of CMD
Broad phenotypic spectrum and genotype-phenotype correlations in GMPPB-related dystroglycanopathies : an Italian cross-sectional study
Get PDFBackground: Dystroglycanopathy (alpha-DG) is a relatively common, clinically and genetically heterogeneous category of congenital forms of muscular dystrophy (CMD) and limb-girdle muscular dystrophy (LGMD) associated with hypoglycosylated alpha-dystroglycan. To date, mutations in at least 19 genes have been associated with alpha-DG. One of them, GMPPB, encoding the guanosine-diphosphate-mannose (GDP-mannose) pyrophosphorylase B protein, has recently been associated with a wide clinical spectrum ranging from severe Walker-Warburg syndrome to pseudo-metabolic myopathy and even congenital myasthenic syndromes. We re-sequenced the full set of known disease genes in 73 Italian patients with evidence of either reduced or nearly absent alpha-dystroglycan to assess genotype-phenotype correlations in this cohort. We used innovative bioinformatic tools to calculate the effects of all described GMPPB mutations on protein function and attempted to correlate them with phenotypic expressions. Results: We identified 13 additional cases from 12 families and defined seven novel mutations. Patients displayed variable phenotypes including less typical pictures, ranging from asymptomatic hyperCKemia, to arthrogryposis and congenital clubfoot at birth, and also showed neurodevelopmental comorbidities, such as seizures and ataxic gait, as well as autism-spectrum disorder, which is seldom described in clinical reports of dystroglycanopathies. We also demonstrated that few mutations recur in the Italian GMPPB-mutated population and that alterations of protein stability are the main effects of GMPPB missense variants. Conclusion: This work adds to the data on genotype-phenotype correlations in alpha-DG and offers new bionformatic tools to provide the conceptual framework needed to understand the complexity of these disorders.Peer reviewe
Association of common mental disorder symptoms with health and healthcare factors among women in rural western India: results of a cross-sectional survey
No full textFirst author Apurv Soni is a medical student in the MD/PhD Program at UMass Medical School.OBJECTIVES: Information about common mental disorders (CMD) is needed to guide policy and clinical interventions in low-income and middle-income countries. This study's purpose was to characterise the association of CMD symptoms with 3 inter-related health and healthcare factors among women from rural western India based on a representative, cross-sectional survey. SETTING: Surveys were conducted in the waiting area of various outpatient clinics at a tertiary care hospital and in 16 rural villages in the Anand district of Gujarat, India. PARTICIPANTS: 700 Gujarati-speaking women between the ages of 18-45 years who resided in the Anand district of Gujarat, India, were recruited in a quasi-randomised manner. PRIMARY AND SECONDARY OUTCOMES MEASURES: CMD symptoms, ascertained using WHO's Self-Reporting Questionnaire-20 (SRQ-20), were associated with self-reported (1) number of healthcare visits in the prior year; (2) health status and (3) portion of yearly income expended on healthcare. RESULTS: Data from 658 participants were used in this analysis; 19 surveys were excluded due to incompleteness, 18 surveys were excluded because the participants were visiting hospitalised patients and 5 surveys were classified as outliers. Overall, 155 (22·8%) participants screened positive for CMD symptoms (SRQ-20 score ≥8) with most (81.9%) not previously diagnosed despite contact with healthcare provider in the prior year. On adjusted analyses, screening positive for CMD symptoms was associated with worse category in self-reported health status (cumulative OR=9.39; 95% CI 5·97 to 14·76), higher portion of household income expended on healthcare (cumulative OR=2·31; 95% CL 1·52 to 3.52) and increased healthcare visits in the prior year (incidence rate ratio=1·24; 95% CI 1·07 to 1·44). CONCLUSIONS: The high prevalence of potential CMD among women in rural India that is unrecognised and associated with adverse health and financial indicators highlights the individual and public health burden of CMD.MD/Ph
Whose story is it anyway? The ethics of narration and the narration of ethics in Summertime and Die Sneeuslaper
No full textIncludes bibliographical references.This dissertation analyses and compares the narrative strategies in J.M. Coetzee’s Summertime and Marlene van Niekerk’s Die sneeuslaper and considers the implications of these strategies for the authors’ exploration of the ethics of writing. Much has been written about the literary oeuvres of both Coetzee and Van Niekerk, including studies of the translations of Van Niekerk’s Afrikaans novels into English. There are few “interlingual” comparative studies of contemporary works in Afrikaans and English, however, and certainly none to my knowledge which compares the work of Coetzee and Van Niekerk. My contribution to the conversation about Coetzee’s and Van Niekerk’s work, but also to an increasingly multilingual and interconnected South African literary criticism, will be a comparison of one recent work by each of these two authors, written in English and Afrikaans respectively. I draw on the theories of Bakhtin, Barthes and Levinas to consider the ethical dimension of texts in which “double-voicedness”, a questioning not only of existence, but of the self is fore grounded in the content and narrative structure; where there is a shift in focus from the author to the reader (“the birth of the reader”) and “utterances” are made with the response of “the other” in mind
Elevated serum endothelin-1 is an independent predictor of coronary microvascular dysfunction in non-obstructive territories in patients with coronary artery disease
Get PDFEndothelin-1 contributes to the constrictor response of the coronary arteries in patients with ischemia with normal coronary arteries. There is thus increasing evidence that endothelin-1 plays a role in coronary microvascular dysfunction (CMD). We investigated whether elevated endothelin-1 is associated with CMD in patients with coronary artery disease (CAD). We prospectively studied 49 consecutive CAD patients with 1- or 2-vessel disease (age 71 +/- 10 years, 43 males). Myocardial blood flow (MBF) was measured by O-15-water PET/CT at rest and during stress, and the coronary flow reserve (CFR) was calculated by dividing the stress MBF by the rest MBF. A CFR of less than 2.0 in non-obstructive regions was defined as a marker of CMD. Eighteen out of 49 (37%) CAD patients had CMD. Endothelin-1 in patients with CMD was significantly higher than in those without CMD (2.27 +/- 0.81 vs. 1.64 +/- 0.48 pg/mL, P = 0.001). Accordingly, univariate ROC analysis showed that the continuous endothelin-1 levels significantly discriminated between the presence and absence of CMD (area under the curve = 0.746 [95%CI 0.592-0.899]). The dichotomous treatment of elevated endothelin-1 as 1.961 pg/mL or more yielded the optimal discriminatory capacity, with a sensitivity of 72.2% and a specificity of 71.0%. High endothelin-1 was still a significant predictor of CMD after adjusting for diabetes mellitus (odds ratio = 6.64 [1.75-25.22], P = 0.005). Endothelin-1 is associated with CMD in non-obstructive territories in patients with CAD, suggesting that endothelin-1 is a potential target for treating CMD in CAD patients
Viabilidade econômico-financeira de um conjunto de alternativas para auxiliar no processo de decisão – caso real de um empreendimento imobiliário
Get PDFTCC (Graduação) - Universidade Federal de Santa Catarina. Centro Socioeconômico. Curso de Ciências ContábeisA oportunidade de compra de um terreno rural reuniu 17 amigos que formaram uma sociedade empresarial para adquirir a terra e constituir um condômino rural. A vontade de fazer desta aquisição um lugar de prazer e diversão mostrou-se mais trabalhosa e dispendiosa do que o imaginado e por isso alguns sócios pretendem desistir do negócio. Com base nas informações contábeis da empresa Taquaras Empreendimentos Imobiliários Ltda. (nome fictício criado para preservar o sigilo da empresa), procurou-se estabelecer valores e índices de rentabilidade os quais atendesse o retorno esperado pelos sócios. Esta análise econômico-financeira visou enfatizar a necessidade de uma visão contábil para a tomada de decisão empresarial, utilizando técnicas de administração financeira, dados contábeis e demais fatores relevantes para uma decisão segura aos interessados. Foram elaboradas planilhas para a análise dos dados coletados e base de cálculo dos indicadores. Cenários foram criados para explanar as melhores possibilidades do negócio, baseado na TMA, TIR, VPL e payback. Estas alternativas indicadas partiram dos valores efetivos até outubro de 2009, conforme atos e fatos concretizados pela empresa. Cada cenário provou atender às expectativas dos sócios em seu tempo, garantindo o retorno desejado. Valores e prazos foram simulados e os índices obtidos indicam a viabilidade econômico-financeira do projeto em todas as alternativas elaboradas
Simulating the Effect of Lifetime Non-uniformity on Solar Cell Performance Using cmd-PC1D 6 and Griddler 2
No full textAbstractIn this paper we present a novel approach to investigate the influence of non-uniformity in the minority carrier lifetime of c-Si wafers on solar cell efficiency. By using a combination of one-dimensional device modelling (cmd-PC1D 6) and finite element circuit modelling (Griddler 2) we are able to simulate the total IV characteristics of a solar cell based on input from minority carrier lifetime images. With suitable input regarding the optical properties, doping profiles, recombination behaviour and sheet resistance of the passivated and metallized surfaces involved this combined model can be used to predict the total cell efficiency of mc-Si solar cells and other cells with significant lateral variations in wafer quality. Several artificial test cases are investigated in order to determine the sensitivity of the method and the magnitude of the effect of lifetime distribution. We find that using the weighted average of the two-diode parameters J01, J02 and Jlight in most cases provides a good description of total cell performance, correctly describing the IV parameters within an error of ∼0.1 - 0.2% relative as compared to simulations taking the complete lateral distribution over the wafer into account. The deviation was however observed to be up to 1.5% for extreme, artificial cases. By instead assuming an average carrier lifetime over the wafer larger errors are observed, due to the non-linear relation between the two-diode parameters and the bulk lifetime
Study of the process e+e−→KS0KL0 in the center-of-mass energy range 1004–1060 MeV with the CMD-3 detector at the VEPP-2000 e+e− collider
Get PDFAbstractThe e+e−→KS0KL0 cross section has been measured in the center-of-mass energy range 1004–1060 MeV at 25 energy points using 6.1×105 events with KS0→π+π− decay. The analysis is based on 5.9 pb−1 of an integrated luminosity collected with the CMD-3 detector at the VEPP-2000 e+e− collider. To obtain ϕ(1020) meson parameters the measured cross section is approximated according to the Vector Meson Dominance model as a sum of the ρ,ω,ϕ-like amplitudes and their excitations. This is the most precise measurement of the e+e−→KS0KL0 cross section with a 1.8% systematic uncertainty
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