927 resultados para free range type


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High spectral resolution (R similar to 40 000) and signal-to- noise ratio observations of five high Galactic latitude early- type stars taken from the Edinburgh-Cape (EC) Faint Blue Object Survey are presented. These were required to complete a magnitude range-limited survey of young B-type objects with 11 <V <15. Of the five stars, four were rejected on the grounds that they are either subluminous (subdwarf or horizontal branch), were part of a binary system or possessed colours later than the (U - B) = -0.5 cut-off employed. The remaining star in the data set, EC 19596-5356, is found to exhibit normal young B-type stellar properties. A kinematic analysis reveals that an origin in the Galactic disc appears likely for all the stars in the sample. Some statistics are drawn about the number density of young stars in the Galactic halo.

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High-resolution (R approximate to 40 000) echelle spectroscopic observations of 13 high-latitude early-type stars are presented. These stars comprise the final part of a complete magnitude range limited sample based on low-resolution spectroscopy of targets drawn from the Palomar-Green survey. The magnitude range under consideration is 13 less than or equal to B-PG less than or equal to 14.6, corresponding to an approximate distance limit for main-sequence B-type objects of 5 less than or equal to d less than or equal to 40 kpc. Three stars are found to be apparently normal, young stars, based on their positions on the (T-eff, log g) diagram, normal abundance patterns and relatively large projected rotational velocities. A further star, PG 1209+263, was found to belong to the chemically peculiar (CP) silicon star class of objects. The remainder are evolved subluminous stars lying on post- horizontal branch (post-HB) tracks, with the exception of PG 2120+062, which appears to be in a post-asymptotic giant branch evolutionary stage. For the young stars in the sample, we have derived distance and age estimates through comparison of the atmospheric parameters with recent theoretical evolutionary models. We discuss formation scenarios by comparing times-of- flight and evolutionary time-scales. It is found that all stars could have formed in the Galactic disc and been ejected from there soon after their birth, with the exception of PG 1209+263. The adopted proper motion is found to be a crucial factor in the kinematical analysis. We also present some number densities for young B-type halo stars, which indicate that they are extremely scarce objects.

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Aims/hypothesis: Patients with type 1 diabetes mellitus are more susceptible than healthy individuals to exercise-induced oxidative stress and vascular endothelial dysfunction, which has important implications for the progression of disease. Thus, in the present study, we designed a randomised double-blind, placebo-controlled trial to test the original hypothesis that oral prophylaxis with vitamin C attenuates rest and exercise-induced free radical-mediated lipid peroxidation in type 1 diabetes mellitus. Methods: All data were collected from hospitalised diabetic patients. The electron paramagnetic resonance spectroscopic detection of spin-trapped a-phenyl-tert-butylnitrone (PBN) adducts was combined with the use of supporting markers of lipid peroxidation and non-enzymatic antioxidants to assess exercise-induced oxidative stress in male patients with type 1 diabetes (HbA1c 7.9±1%, n=12) and healthy controls (HbA1c 4.6±0.5%, n=14). Following participant randomisation using numbers in a sealed envelope, venous blood samples were obtained at rest, after a maximal exercise challenge and before and 2 h after oral ingestion of 1 g ascorbate or placebo. Participants and lead investigators were blinded to the administration of either placebo or ascorbate treatments. Primary outcome was the difference in changes in free radicals following ascorbate ingestion. Resuts: Six diabetic patients and seven healthy control participants were randomised to each of the placebo and ascorbate groups. Diabetic patients (n=12) exhibited an elevated concentration of PBN adducts (p<0.05 vs healthy, n=14), which were confirmed as secondary, lipid-derived oxygen-centred alkoxyl (RO•) radicals (a nitrogen=1.37 mT and aßhydrogen=0.18 mT). Lipid hydroperoxides were also selectively elevated and associated with a depression of retinol and lycopene (p<0.05 vs healthy). Vitamin C supplementation increased plasma vitamin C concentration to a similar degree in both groups (p<0.05 vs pre-supplementation) and attenuated the exercise-induced oxidative stress response (p<0.05 vs healthy). There were no selective treatment differences between groups in the primary outcome variable. Conclusions/ interpretation: These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.

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We present optical and near-infrared photometry and spectroscopy of the Type Ia SN 2003cg, which exploded in the nearby galaxy NGC 3169. The observations cover a period between -8.5 and +414 d post-maximum. SN 2003cg is a normal but highly reddened Type Ia event. Its B magnitude at maximum B-max = 15.94 +/- 0.04 and Delta m(15)(B)(obs) = 1.12 +/- 0.04 [Delta m(15)(B)(intrinsic) = 1.25 +/- 0.05]. Allowing R-V to become a free parameter within the Cardelli et al. extinction law, simultaneous matches to a range of colour curves of normal SNe Ia yielded E(B - V) = 1.33 +/- 0.11, and RV = 1.80 +/- 0.19. While the value obtained for R-V is small, such values have been invoked in the past, and may imply a grain size which is small compared with the average value for the local interstellar medium.

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Background. Accurate quantification of the prevalence of human immunodeficiency virus type 1 (HIV-1) drug resistance in patients who are receiving antiretroviral therapy (ART) is difficult, and results from previous studies vary. We attempted to assess the prevalence and dynamics of resistance in a highly representative patient cohort from Switzerland. Methods. On the basis of genotypic resistance test results and clinical data, we grouped patients according to their risk of harboring resistant viruses. Estimates of resistance prevalence were calculated on the basis of either the proportion of individuals with a virologic failure or confirmed drug resistance (lower estimate) or the frequency-weighted average of risk group-specific probabilities for the presence of drug resistance mutations (upper estimate). Results. Lower and upper estimates of drug resistance prevalence in 8064 ART-exposed patients were 50% and 57% in 1999 and 37% and 45% in 2007, respectively. This decrease was driven by 2 mechanisms: loss to follow-up or death of high-risk patients exposed to mono- or dual-nucleoside reverse-transcriptase inhibitor therapy (lower estimates range from 72% to 75%) and continued enrollment of low-risk patients who were taking combination ART containing boosted protease inhibitors or nonnucleoside reverse-transcriptase inhibitors as first-line therapy (lower estimates range from 7% to 12%). A subset of 4184 participants (52%) had 1 study visit per year during 2002-2007. In this subset, lower and upper estimates increased from 45% to 49% and from 52% to 55%, respectively. Yearly increases in prevalence were becoming smaller in later years. Conclusions. Contrary to earlier predictions, in situations of free access to drugs, close monitoring, and rapid introduction of new potent therapies, the emergence of drug-resistant viruses can be minimized at the population level. Moreover, this study demonstrates the necessity of interpreting time trends in the context of evolving cohort populations.

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Introduction Health promotion (HP) aims to enhance good health while preventing ill-health at three levels of activity; primary (preventative), secondary (diagnostic) and tertiary (management).1 It can range from simple provision of health education to ongoing support, but the effectiveness of HP is ultimately dependent on its ability to influence change. HP as part of the Community Pharmacy Contract (CPC) aims to increase public knowledge and target ‘hard-to-reach’ individuals by focusing mainly on primary and tertiary HP. The CPC does not include screening programmes (secondary HP) as a service. Coronary heart disease (CHD) is a significant cause of morbidity and mortality in the UK. While there is evidence to support the effectiveness of some community pharmacy HP strategies in CHD, there is paucity of research in relation to screening services.2 Against this background, Alliance Pharmacy introduced a free CHD risk screening programme to provide tailored HP advice as part of a participant–pharmacist consultation. The aim of this study is to report on the CHD risk levels of participants and to provide a qualitative indication of consultation outcomes. Methods Case records for 12 733 people who accessed a free CHD risk screening service between August 2004 and April 2006 offered at 217 community pharmacies were obtained. The service involved initial self-completion of the Healthy Heart Assessment (HHA) form and measurement of height, weight, body mass index, blood pressure, total cholesterol and highdensity lipoprotein levels by pharmacists to calculate CHD risk.3 Action taken by pharmacists (lifestyle advice, statin recommendation or general practitioner (GP) referral) and qualitative statements of advice were recorded, and a copy provided to the participants. The service did not include follow-up of participants. All participants consented to taking part in evaluations of the service. Ethical committee scrutiny was not required for this service development evaluation. Results Case records for 10 035 participants (3658 male) were evaluable; 5730 (57%) were at low CHD risk (<15%); 3636 (36%) at moderate-to-high CHD risk (≥15%); and 669 (7%) had existing heart disease. A significantly higher proportion of male (48% versus 30% female) participants were at moderate- to-high risk of CHD (chi-square test; P < 0.005). A range of outcomes resulted from consultations. Lifestyle advice was provided irrespective of participants’ CHD risk or existing disease. In the moderate-to-high-risk group, of which 52% received prescribed medication, lifestyle advice was recorded for 62%, 16% were referred and 34% were advised to have a re-assessment. Statin recommendations were made in 1% of all cases. There was evidence of supportive and motivational statements in the advice recorded. Discussion Pharmacists were able to identify individuals’ level of CHD risk and provide them with bespoke advice. Identification of at-risk participants did not automatically result in referrals or statin recommendation. One-third of those accessing the screening service had moderate-to-high risk of CHD, a significantly higher proportion of whom were men. It is not known whether these individuals had been previously exposed to HP but presumably by accessing this service they may have contemplated change. As effectiveness of HP advice will depend among other factors on ability to influence change, future consultations may need to explore patients’ attitude towards change in relation to the Trans Theoretical Model4 to better tailor HP advice. The high uptake of the service by those at moderate-to-high CHD risk indicates a need for this type of screening programme in community pharmacy, perhaps specifically to reach men who access medical services less.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Há uma grande lacuna no conhecimento da biologia e corologia de Nyctinomops aurispinosus. Nesta comunicação, nós apresentamos o registro mais austral deste molossídeo, realizado na cidade de Curitiba (25° 25' S e 49° 15' W, 920 m), estado do Paraná, Brasil, e sumarizamos a distribuição geográfica conhecida para a espécie na América do Sul.

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The holographic imaging of rigid objects with diode lasers emitting in many wavelengths in a sillenite Bi12TiO20 photorefractive crystal is both theoretically an experimentally investigated. It is shown that, due to the multi-wavelength emission and the typically large free spectral range of this light source, contour fringes appear on the holographic image corresponding to the surface relief, even in single-exposure recordings. The influence of the number of emitted modes on the fringe width is analysed, and the possible applications of the contour fringes in the field of optical metrology are pointed out.

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An accurate estimate of machining time is very important for predicting delivery time, manufacturing costs, and also to help production process planning. Most commercial CAM software systems estimate the machining time in milling operations simply by dividing the entire tool path length by the programmed feed rate. This time estimate differs drastically from the real process time because the feed rate is not always constant due to machine and computer numerical controlled (CNC) limitations. This study presents a practical mechanistic method for milling time estimation when machining free-form geometries. The method considers a variable called machine response time (MRT) which characterizes the real CNC machine's capacity to move in high feed rates in free-form geometries. MRT is a global performance feature which can be obtained for any type of CNC machine configuration by carrying out a simple test. For validating the methodology, a workpiece was used to generate NC programs for five different types of CNC machines. A practical industrial case study was also carried out to validate the method. The results indicated that MRT, and consequently, the real machining time, depends on the CNC machine's potential: furthermore, the greater MRT, the larger the difference between predicted milling time and real milling time. The proposed method achieved an error range from 0.3% to 12% of the real machining time, whereas the CAM estimation achieved from 211% to 1244% error. The MRT-based process is also suggested as an instrument for helping in machine tool benchmarking.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A numerical study of mass conservation of MAC-type methods is presented, for viscoelastic free-surface flows. We use an implicit formulation which allows for greater time steps, and therefore time marching schemes for advecting the free surface marker particles have to be accurate in order to preserve the good mass conservation properties of this methodology. We then present an improvement by using a Runge-Kutta scheme coupled with a local linear extrapolation on the free surface. A thorough study of the viscoelastic impacting drop problem, for both Oldroyd-B and XPP fluid models, is presented, investigating the influence of timestep, grid spacing and other model parameters to the overall mass conservation of the method. Furthermore, an unsteady fountain flow is also simulated to illustrate the low mass conservation error obtained.

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In this paper we present a finite difference MAC-type approach for solving three-dimensional viscoelastic incompressible free surface flows governed by the eXtended Pom-Pom (XPP) model, considering a wide range of parameters. The numerical formulation presented in this work is an extension to three-dimensions of our implicit technique [Journal of Non-Newtonian Fluid Mechanics 166 (2011) 165-179] for solving two-dimensional viscoelastic free surface flows. To enhance the stability of the numerical method, we employ a combination of the projection method with an implicit technique for treating the pressure on the free surfaces. The differential constitutive equation of the fluid is solved using a second-order Runge-Kutta scheme. The numerical technique is validated by performing a mesh refinement study on a pipe flow, and the numerical results presented include the simulation of two complex viscoelastic free surface flows: extrudate-swell problem and jet buckling phenomenon. © 2013 Elsevier B.V.