4,044 research outputs found

    Relativistic quantum motion of spin-0 particles under the influence of non-inertial effects in the cosmic string space-time

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    We study solutions for the Klein-Gordon equation with vector and scalar potentials of the Coulomb types under the influence of non-inertial effects in the space-time of topological defects. We also investigate a quantum particle described by the Klein-Gordon oscillator in the background space-time generated by a string. An important result obtained is that the non-inertial effects restrict the physical region of the space-time where the particle can be placed. In addition, we show that these potentials can form bound states for the relativistic wave equation equation in this kind of background.Comment: arXiv admin note: text overlap with arXiv:1608.0669

    Gender, socio-economic status and metabolic syndrome in middle-aged and old adults.

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    BACKGROUND: Studies that addressed social and economic determinants of cardiovascular diseases, consistently showed an increase prevalence of the individual features of metabolic syndrome in the lower socio-economic strata. Thus, this study aimed to evaluate the association between social class and metabolic syndrome in a sample of urban middle-aged and old Portuguese adults. METHODS: We evaluated 1962 subjects (1207 women and 755 men) aged 40 or more years. Marital status, education, occupation, menarche age and height distribution were used as socioeconomic indicators. Metabolic syndrome was defined according to the ATP III, by the presence of at least three of the following characteristics: waist circumference > 102 cm in men and > 88 cm in women; triglycerides > or = 150 mg/dl; HDL cholesterol or = 130/85 mm Hg; and fasting glucose > or = 110 mg/dl. Proportions were compared using the chi square test or Fisher's exact test. Odds ratios (OR) and 95% confidence intervals (95% CI) were computed using unconditional logistic regression to estimate the magnitude of the associations. RESULTS: Metabolic syndrome was significantly more frequent in females (24.9 vs. 17.4, p < 0.001). In females, the odds favoring metabolic syndrome significantly increased with age and in unfavorable social class as described by occupation, and decreased with education level. In males, metabolic syndrome was significantly more frequent in the 60-69 years age class (OR = 1.82; 95%CI: 1.02-3.26) when compared to those in the 40-49 years age class. Concerning other socioeconomic indicators no significant associations were found. CONCLUSION: This study showed that gender influenced the association of socio-economic status indicators with metabolic syndrome. Females in lower social classes, as defined by education and occupational classification, more frequently presented metabolic syndrome, no such association was found in males

    Klein-Gordon oscillator in a topologically nontrivial space-time

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    In this study, we analyze solutions of the wave equation for scalar particles in a space-time with nontrivial topology. Solutions for the Klein--Gordon oscillator are found considering two configurations of this space-time. In the first one, it is assumed the S1×R3S^{1}\times R^{3} space where the metric is written in the usual inertial frame of reference. In the second case, we consider a rotating reference frame adapted to the circle S1. We obtained compact expressions for the energy spectrum and for the particles wave functions in both configurations. Additionally, we show that the energy spectrum of the solution associated to the rotating system has an additional term that breaks the symmetry around E=0E = 0

    Detecting transit signatures of exoplanetary rings using SOAP3.0

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    CONTEXT. It is theoretically possible for rings to have formed around extrasolar planets in a similar way to that in which they formed around the giant planets in our solar system. However, no such rings have been detected to date. AIMS: We aim to test the possibility of detecting rings around exoplanets by investigating the photometric and spectroscopic ring signatures in high-precision transit signals. METHODS: The photometric and spectroscopic transit signals of a ringed planet is expected to show deviations from that of a spherical planet. We used these deviations to quantify the detectability of rings. We present SOAP3.0 which is a numerical tool to simulate ringed planet transits and measure ring detectability based on amplitudes of the residuals between the ringed planet signal and best fit ringless model. RESULTS: We find that it is possible to detect the photometric and spectroscopic signature of near edge-on rings especially around planets with high impact parameter. Time resolution \leq 7 mins is required for the photometric detection, while 15 mins is sufficient for the spectroscopic detection. We also show that future instruments like CHEOPS and ESPRESSO, with precisions that allow ring signatures to be well above their noise-level, present good prospects for detecting rings.Comment: 13 pages, 16 figures, 2 tables , accepted for publication in A&

    Occupational stress and coping resources in physiotherapists: a survey of physiotherapists in three general hospitals

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    Objectives - To identify occupational stressors and coping resources in a group of physiotherapists, and to analyse interactions between subjective levels of stress, efficacy in stress resolution and coping resources used by these professionals. Design - A sample of 55 physiotherapists working in three general hospitals in Portugal completed the Coping Resources Inventory for Stress, the Occupational Stressors Inventory and two subjective scales for stress and stress resolution. Main results - Most physiotherapists perceived that they were moderately stressed (19/55, 35%) or stressed (20/55, 36%) due to work, and reported that their efficacy in stress resolution was moderate (25/54, 46%) or efficient (23/54, 42%). Issues related to lack of professional autonomy, lack of organisation in the hierarchical command chain, lack of professional and social recognition, disorganisation in task distribution and interpersonal conflicts with superiors were identified as the main sources of stress. The most frequently used coping resources were social support, stress monitoring, physical health and structuring. Perceived efficacy in stress resolution was inversely related to perceived level of occupational stress (r = −0.61, P < 0.01). Significant correlations were found between several coping resources and the perceived level of stress and efficacy in stress resolution. Associations between problem solving, cognitive restructuring and stress monitoring and both low levels of perceived stress and high levels of perceived efficacy were particularly strong. Implications for practice - The importance of identifying stressors and coping resources related to physiotherapists’ occupational stress, and the need for the development of specific training programmes to cope with stress are supported

    Parâmetros de qualidade tecnológica de grãos em seis genótipos de feijão-caupi cultivados em regime irrigado.

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    O presente trabalho foi conduzido na Embrapa Semi-Árido, em Petrolina, PE, com o objetivo de avaliar a qualidade tecnológica em genótipos de feijão-caupi em regime irrigado. Foram avaliadas as seguintes variáveis: porcentagem de embebição de água antes do cozimento (PEANC), porcentagem de embebição de água após o cozimento (PEAPC), determinação da taxa de expansão volumétrica dos grãos após o cozimento (EV) e porcentagem de grãos inteiros após o cozimento (PGI). Os quadrados médios de tratamento foram significativos (p<0,05) pelo teste F para as variáveis PEANC e PGI. O 'Canapu' apresentou o maior valor para PEANC, deferindo significativamente dos demais tratamentos. A variável PEANC variou de 116,8% a 134,3%. A PEAPC variou de 78,7% a 90,3%, tendo sido maior para a linhagem PC 95-05-12-2-2, que diferiu significativamente da cultivar IPA 206. Apenas a correlação fenotípica entre Peapc x EV foi significativa, tendo sido negativa. No geral, estes resultados são indicativos de que as linhagens selecionadas na Embrapa Semi-Árido apresentam qualidade tecnológica de grãos aceitáveis pelo mercado, sendo que um esforço maior deverá ser enfatizado no sentido de elevar a porcentagem de embebição antes do cozimento para níveis próximos ao 'Canapu', que é um tipo bastante aceito pelo mercado
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