2,348 research outputs found
Ferromagnetism in Ga1-xMnxP: evidence for inter-Mn exchange mediated by localized holes within a detached impurity band
Journal ArticleWe report an energy gap for hole photoexcitation in ferromagnetic Ga1-xMnxP that is tunable by Mn concentration (x ≤ 0:06) and by compensation with Te donors. For x ~ 0:06, electrical transport is dominated by excitation across this gap above the Curie temperature (TC) of 60 K and by thermally activated hopping below TC. Magnetization measurements reveal a moment of 3:9 ± 0:4μB per substitutional Mn while the large anomalous Hall signal demonstrates that the ferromagnetism is carrier mediated. In aggregate these data indicate that ferromagnetic exchange is mediated by holes localized in a Mn-derived band that is detached from the valence band
Análise de metilxantinas em dezesseis progĂŞnies de erva mate extraĂdas por diĂłxido de carbono supercrĂtico.
A Ilex paraguariensis apresenta grande potencial de utilização pela diversidade de seus compostos quĂmicos. Dentre os principais grupos de compostos presentes em erva mate citam-se as metilxantinas, com predominância de cafeĂna, teobromina e traços de teofilina. Na quantificação convencional destes compostos utiliza-se extração com solvente orgânico que expressa o conteĂşdo total de cafeĂna presente na amostra. Como forma alternativa de obtenção das metilxantinas pode-se utilizar a extração por fluĂdo supercrĂtico (EFSC). Esta extração caracteriza-se pela obtenção de produtos de elevada qualidade, sem as inconveniĂŞncias de resĂduos de solventes e alterações nas propriedades do extrato presente na extração convencional. O objetivo deste trabalho foi quantificar metilxantinas presentes nas amostras de dezesseis progĂŞnies oriundas de quatro procedĂŞncias (IvaĂ/PR, BarĂŁo de Cotegipe/RS, Quedas do Iguaçu/PR e Cascavel/PR), cultivadas em trĂŞs localidades (IvaĂ/PR, Rio Azul/PR e Guarapuava/PR) utilizando a extração por solventes orgânicos e pela EFSC usando como solvente o CO2. As metilxantinas foram quantificadas por HPLC e espectrometria comparando-se com padrĂŁo. Os teores mĂ©dios de metilxantinas, correspondendo Ă soma de cafeĂna e teobromina, foram de 19,112 mg/100 g nas progĂŞnies de IvaĂ/PR, 8,906 mg/100 g nas progĂŞnies de Rio Azul/PR e de 12,796 mg/100 g nas progĂŞnies de Guarapuava/PR. Ao compararmos a extração supercrĂtica com a extração convencional de cafeĂna os valores mĂ©dios encontrados foram de 2,808±0,7 % para IvaĂ/PR, 1,537±0,2 % em Rio Azul/PR e 1,728±0,5 % para Guarapuava/PR. A EFSC usando o diĂłxido de carbono como solvente aliada Ă análise HPLC mostrou-se eficiente na caracterização e quantificação das metilxantinas presentes nas amostras analisadas.Seção: Controle de Qualidade/ Composição QuĂmica. Feira do AgronegĂłcio da Erva-mate, 1., 2003, ChapecĂł. Integrar para promover o agronegĂłcio da erva-mate
Pop-Up Class: Defending Immigrants\u27 Rights in the Aftermath of President Trump\u27s Executive Order
https://larc.cardozo.yu.edu/event-invitations-2017/1004/thumbnail.jp
Vascular risk factors for male and female urgency urinary incontinence at age 68 years from a British birth cohort study
OBJECTIVE: To investigate the prevalence of urgency urinary incontinence (UUI) at age 68 years and the contribution of vascular risk factors to male and female UUI pathogenesis in addition to the associations with raised body mass index (BMI). SUBJECTS AND METHODS: In all, 1 762 participants from the Medical Research Council (MRC) National Survey for Health and Development birth cohort who answered the International Consultation on Incontinence Questionnaire short form (ICIQ-SF), at age 68 years, were included. Logistic regression was used to estimate associations between UUI and earlier life vascular risk factors including: lipid status, diabetes, hypertension, BMI, previous stroke or transient ischaemic attack (TIA) diagnosis; adjusting for smoking status, physical activity, co-presentation of stress UI symptoms, educational attainment; and in women only, type of menopause, age at period cessation, and use of hormone replacement therapy (HRT). RESULTS: UUI was reported by 12% of men and 19% of women at age 68 years. Female sex, previous stroke or TIA diagnosis, increased BMI and hypertension (in men only) at age 60-64 years were independent risk factors for UUI. Female sex, increased BMI, and a previous diagnosis of stroke/TIA increased the relative risk of more severe UUI symptoms. Type and timing of menopause and HRT use did not alter the estimated associations between UUI and vascular risk factors in women. CONCLUSION: Multifactorial mechanisms lead to UUI and vascular risk factors may contribute to the pathogenesis of bladder overactivity in addition to higher BMI. Severe UUI appears to be a distinct presentation with more specific contributory mechanisms than milder UUI
Could Reduced Fluid Intake Cause the Placebo Effect Seen in Overactive Bladder Clinical Trials? Analysis of a Large Solifenacin Integrated Database
Objective
To assess the hypothesis that patients receiving placebo in overactive bladder (OAB) trials who experience less benefit from “treatment” continue with behavioral modifications such as fluid restriction, whereas those on active treatment adopt more normal drinking patterns. This may manifest itself as a reduction in micturition frequency (MF).
Materials and Methods
We interrogated a large integrated database containing pooled patient data from 4 randomized, placebo-controlled phase III OAB solifenacin studies. A statistical correction was applied to MF to remove the influence of fluid intake.
Results
Pooled analysis using patient-level data from 3011 patients and accounting for the studies within the models showed that all patients voided progressively less total urine per 24 hours during treatment than at baseline. However, reduction in total urine volume voided per 24 hours was larger in patients receiving placebo vs those on solifenacin; with a substantial decrease in 24-hour urine output in the placebo group from baseline to week 4, which was not the case in active groups. After correcting MF for volume voided for each patient using the statistical correction and averaging the corrected MF per treatment arm, the placebo effect almost disappeared. Patients on solifenacin voided less often, with a statistically significant increase in volume voided each time they voided, vs placebo.
Conclusion
Assuming volume voided is a good surrogate measure for fluid intake, this analysis shows that fluid restriction almost completely explains the reduction in MF in the placebo group. In contrast, patients receiving active treatment adopt more normal drinking patterns once they start to perceive improvement in their OAB symptoms
The impact of free trade agreements on Middle East and North Africa exports of intermediate and final goods
This paper is the first to analyse the impact of free trade agreements (FTAs) and the harmonisation of rules of origin (RoO) on Middle East and North African (MENA) countries’ exports differentiating between final and in-termediate goods for a global sample of trade partners. Data on exports from four MENA countries (Egypt, Jordan, Morocco and Tunisia) to 61 destinations over the period 1995– 2016 are used to estimate a structural gravity model applying a Poisson Pseudo Maximum Likelihood (PPML) estimator. Moreover, the paper esti-mates the effect of the progressive adoption of the Pan- European- Mediterranean RoO. Results show that FTAs have been overall successful in increasing MENA ex-ports. This is particularly true for FTAs that eliminate protection on agricultural products. In contrast to the ex-isting literature, we find that the agreements concluded with European countries raise MENA exports, whereas no significant impact is found for the application of the Pan- European RoO
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The Isolation, Differentiation, and Survival In Vivo of Multipotent Cells from the Postnatal Rat filum terminale
Neural stem cells (NSCs) are undifferentiated cells in the central nervous system (CNS) that are capable of self-renewal and can be induced to differentiate into neurons and glia. Current sources of mammalian NSCs are confined to regions of the CNS that are critical to normal function and surgically difficult to access, which limits their therapeutic potential in human disease. We have found that the filum terminale (FT), a previously unexplored, expendable, and easily accessible tissue at the caudal end of the spinal cord, is a source of multipotent cells in postnatal rats and humans. In this study, we used a rat model to isolate and characterize the potential of these cells. Neurospheres derived from the rat FT are amenable to in vitro expansion in the presence of a combination of growth factors. These proliferating, FT-derived cells formed neurospheres that could be induced to differentiate into neural progenitor cells, neurons, astrocytes, and oligodendrocytes by exposure to serum and/or adhesive substrates. Through directed differentiation using sonic hedgehog and retinoic acid in combination with various neurotrophic factors, FT-derived neurospheres generated motor neurons that were capable of forming neuromuscular junctions in vitro. In addition, FT-derived progenitors that were injected into chick embryos survived and could differentiate into both neurons and glia in vivo
Is there a link between overactive bladder and the metabolic syndrome in women? : A systematic review of observational studies
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.To conduct a systematic review to determine whether there is an association between metabolic syndrome (MetS) and lower urinary tract symptoms (LUTS) or overactive bladder (OAB) in women. We systematically reviewed English language observational studies on the effect of MetS (or component factors) on the presence of OAB or LUTS in women. We searched PubMed, Web of Science and The Cochrane Library with no date restrictions, checked reference lists and undertook citation searches in PubMed and Google Scholar. Studies were assessed for risk of bias. Because of heterogeneity, results were not pooled, but are reported narrativelyPeer reviewe
Young and Early Career Investigators: Report from a Global HIV Vaccine Enterprise Working Group
The scientific challenges facing HIV-1 vaccine development are unprecedented in the history of vaccinology. As a result, investigators, funders, and other stakeholders generally agree that “game-changing” ideas are required. While innovation can certainly arise from investigators at all career stages, young and early-career investigators, defined as those under 40 years of age or within 10 years of their final degree or clinical training, are especially key contributors of novel and transformative ideas. Young and early-career investigators bring energy, enthusiasm, and fresh perspectives that are unbiased by prevailing dogma and that are essential to scientific progress
Variação no teor de cafeĂna em dezesseis progĂŞnies de erva-mate (Ilex paraguariensis St. Hil.) cultivadas em trĂŞs municĂpios do Paraná.
A erva mate (Ilex paraguariensis S. Hil.) Ă© utilizada como bebida tradicional na regiĂŁo sul do Brasil, e tem sido pesquisada pela diversidade de sua composição quĂmica. Dos constituintes quĂmicos relacionados a esta espĂ©cie destacam-se metilxantinas: cafeĂna, teobromina e teofilina. Este trabalho teve como objetivo analisar a variação na concentração de cafeĂna em progĂŞnies de erva mate correlacionando com procedĂŞncia e local de cultivo. Dezesseis progĂŞnies de quatro procedĂŞncias (IvaĂ/PR, BarĂŁo de Cotegipe/RS, Quedas do Iguaçu/PR e Cascavel/PR) foram selecionadas entre as mais produtivas de teste de progĂŞnies, cultivadas em trĂŞs áreas experimentais nos municĂpios de IvaĂ/PR, Rio Azul/PR e Guarapuava/PR. Amostras de trĂŞs blocos foram coletadas entre os meses de julho/setembro de 2001, selecionadas, estabilizadas e secas em estufa com circulação de ar a 45ÂşC. Determinou-se a porcentagem de cafeĂna por espectrofotometria, apĂłs extração com clorofĂłrmio. Utilizou-se Teste de Tukey com 5% de significância. As mĂ©dias encontradas para cafeĂna foram de 0,675 ± 0,146% em IvaĂ, 0,576 ± 0,103% em Rio Azul e 0,741 ± 0,189% em Guarapuava, com diferenças significativas entre as localidades de Rio Azul e Guarapuava. Em relação Ă s procedĂŞncias, diferenças significativas, somente foram obtidas nos teores de cafeĂna da procedĂŞncia de Cascavel com IvaĂ. Nas trĂŞs localidades as diferenças entre as progĂŞnies com maiores e menor teor de cafeĂna foram marcantes. Conclui-se que dentro dos parâmetros observados houve diferença na concentração de cafeĂna entre as dezesseis progĂŞnies avaliadas, sendo que a localidade e a procedĂŞncia tambĂ©m influenciaram significativamente na concentração de cafeĂna em erva mate.Seção: Controle de Qualidade/ Composição QuĂmica. Feira do AgronegĂłcio da Erva-mate, 1., 2003, ChapecĂł. Integrar para promover o agronegĂłcio da erva-mate
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