504 research outputs found

    High-precision transit observations of the exoplanet WASP-13b with the RISE instrument

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    WASP-13b is a sub-Jupiter mass exoplanet orbiting a G1V type star with a period of 4.35 d. The current uncertainty in its impact parameter (0 < b < 0.46) results in poorly defined stellar and planetary radii. To better constrain the impact parameter, we have obtained high-precision transit observations with the rapid imager to search for exoplanets (RISE) instrument mounted on 2.0-m Liverpool Telescope. We present four new transits which are fitted with a Markov chain Monte Carlo routine to derive accurate system parameters. We found an orbital inclination of 85°.2 ± 0°.3 resulting in stellar and planetary radii of 1.56 ± 0.04 R⊙ and 1.39 ± 0.05RJup, respectively. This suggests that the host star has evolved off the main sequence and is in the hydrogen-shell-burning phase. We also discuss how the limb darkening affects the derived system parameters. With a density of 0.17ρJ, WASP-13b joins the group of low-density planets whose radii are too large to be explained by standard irradiation models. We derive a new ephemeris for the system, T0= 245 5575.5136 ± 0.0016 (HJD) and P= 4.353 011 ± 0.000 013 d. The planet equilibrium temperature (Tequ= 1500 K) and the bright host star (V= 10.4 mag) make it a good candidate for follow-up atmospheric studies

    A transit timing analysis of seven RISE light curves of the exoplanet system HAT-P-3

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    We present seven light curves of the exoplanet system HAT-P-3, taken as part of a transit timing programme using the rapid imager to search for exoplanets instrument on the Liverpool Telescope. The light curves are analysed using a Markov chain Monte Carlo algorithm to update the parameters of the system. The inclination is found to be i= 86.75+0.22−0.21 °, the planet-star radius ratio to be Rp/R★= 0.1098+0.0010−0.0012 and the stellar radius to be R★= 0.834+0.018−0.026 R⊙, consistent with previous results but with a significant improvement in the precision. Central transit times and uncertainties for each light curve are also determined, and a residual permutation algorithm is used as an independent check on the errors. The transit times are found to be consistent with a linear ephemeris, and a new ephemeris is calculated as Tc(0) = 245 4856.701 18 ± 0.000 18 HJD and P= 2.899 738 ± 0.000 007 d. Model timing residuals are fitted to the measured timing residuals to place upper mass limits for a hypothetical perturbing planet as a function of the period ratio. These show that we have probed for planets with masses as low as 0.33 and 1.81 M⊕ in the interior and exterior 2:1 resonances, respectively, assuming the planets are initially in circular orbits

    Land-Use and Legislation-Based Methodology for the Implementation of Sustainable Drainage Systems in the Semi-Arid Region of Brazil

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    This is the final version. Available on open access from MDPI via the DOI in this recordIn developing countries, the urbanisation process occurs with empirical urban management, a high increase of impermeable areas, and a lack of connection between water resource management and planning. In Brazil, concentrated rainfall and ineffective urban drainage systems add to this context and may impact the population with flash floods. Although sustainable drainage systems (SuDS) are widely used for flood mitigation, it is still not very well known how those strategies behave in semi-arid regions, where most of the time the weather is very dry. In Brazil, flood mitigation still mostly involves structural measures such as larger pipes or channels, with limited guidance for SuDS use due to the great resistance to change by citizens and managers. This study sought to analyse the efficacy of SuDS in Campina Grande, a semi-arid region of Brazil. A land-use and legislation-based methodology was developed with physical, climate, hydrological and governance data for three catchments and 312 sub-catchments in 30 applications and simulations. Simulations suggest that these strategies would be appropriate for semi-arid regions, with reductions in the flooded area, flooding volume, and impacts. This study is of relevance for cities with a similar climate to reach a sustainable level of urban drainage services, supporting the integration of urban planning and water resources management.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (Capes

    Avaliação das técnicas de massagem e ordenha no tratamento do ingurgitamento mamário por termografia

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    OBJETIVO: evaluar los métodos de masaje y bombeo en el tratamiento de la congestión mamaria posparto a través de la termografía. MÉTODO: el estudio se realizó en el Banco de Leche Humana de un hospital en Curitiba, Brasil. Se seleccionaron al azar 16 mujeres en periodo de lactancia con congestión con clasificación lobar, ampular y glandular, moderada e intensa. Se compararon los patrones diferenciales de temperatura, antes y después del tratamiento por medio de masaje y bombeo. RESULTADOS: se encontró un degradado negativo de 0,3°C de temperatura entre el pre y post-tratamiento en el grupo experimental. Las mamas con intensa congestión eran 0,7°C más caliente en comparación a aquellos con congestión moderada. CONCLUSIÓN: el masaje y el bombeo electromecánico fueron superiores a los métodos manuales cuando se evaluaron por termografía. REBEC: U1111-1136-9027.OBJETIVO: avaliar técnicas de massagem e ordenha no tratamento do ingurgitamento mamário puerperal, por meio da termografia. MÉTODO: a pesquisa foi realizada no Banco de Leite Humano de um hospital de Curitiba, Brasil. Selecionaram-se, aleatoriamente, 16 lactantes com ingurgitamento com classificação lobar, ampolar e glandular moderado e intenso. Compararam-se os padrões diferenciais de temperatura, antes e após o tratamento realizado, por meio de massagem e ordenha. RESULTADOS: constatou-se um gradiente negativo de 0,3ºC de temperatura entre o pré e o pós-tratamento no grupo experimental. Mamas com ingurgitamento intenso foram 0,7ºC mais quentes quando comparadas com ingurgitamento moderado. CONCLUSÃO: a massagem e ordenha eletromecânicas são superiores às manuais, quando avaliadas por termografia. REBEC: U1111-1136-9027.OBJECTIVE: to evaluate techniques of massage and pumping in the treatment of postpartum breast engorgement through thermography. METHOD: the study was conducted in the Human Milk Bank of a hospital in Curitiba, Brazil. We randomly selected 16 lactating women with engorgement with the classification lobar, ampullary and glandular, moderate and intense. We compared the differential patterns of temperature, before and after the treatment by means of massage and pumping. RESULTS: we found a negative gradient of 0.3°C of temperature between the pre- and post-treatment in the experimental group. Breasts with intense engorgement were 0.7°C warmer when compared with moderate engorgement. CONCLUSION: massage and electromechanical pumping were superior to manual methods when evaluated by thermography. REBEC: U1111-1136-9027

    Oral health status of 12-year-old school children in Khartoum state, the Sudan; a school-based survey

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    <p>Abstract</p> <p>Background</p> <p>Few studies have investigated the prevalence of dental caries among school children in the past decades in Sudan rendering it difficult to understand the status and pattern of oral health.</p> <p>Methods</p> <p>A school-based survey was conducted using stratified random cluster sampling in Khartoum state, Sudan. Data was collected through interviews and clinical examination by a single examiner. DMFT was measured according to WHO criteria. Gingival index (GI) of Loe & Silness and Plaque index (PI) of Silness & Loe were used.</p> <p>Results</p> <p>The mean DMFT for 12-year-olds was found to be 0.42 with a significant caries index (SiC) of 1.4. Private school attendees had significantly higher DMFT (0.57) when compared to public school attendees (0.4). The untreated caries prevalence was 30.5%. In multivariate analysis caries experience (DMFT > 0) was found to be significantly and directly associated with socioeconomic status. The mean GI for the six index teeth was found to be 1.05 (CI 1.03 – 1.07) and the mean PI was 1.30 (CI 1.22 – 1.38).</p> <p>Conclusion</p> <p>The prevalence of caries was found to be low. The school children with the higher socioeconomic status formed the high risk group.</p

    Targeting pathogen metabolism without collateral damage to the host

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    The development of drugs that can inactivate disease-causing cells (e.g. cancer cells or parasites) without causing collateral damage to healthy or to host cells is complicated by the fact that many proteins are very similar between organisms. Nevertheless, due to subtle, quantitative differences between the biochemical reaction networks of target cell and host, a drug can limit the flux of the same essential process in one organism more than in another. We identified precise criteria for this â €network-based' drug selectivity, which can serve as an alternative or additive to structural differences. We combined computational and experimental approaches to compare energy metabolism in the causative agent of sleeping sickness, Trypanosoma brucei, with that of human erythrocytes, and identified glucose transport and glyceraldehyde-3-phosphate dehydrogenase as the most selective antiparasitic targets. Computational predictions were validated experimentally in a novel parasite-erythrocytes co-culture system. Glucose-transport inhibitors killed trypanosomes without killing erythrocytes, neurons or liver cells
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