992 resultados para 198-1209
Resumo:
Objectives Impaired muscle function is common in knee osteoarthritis (OA). Numerous biochemical molecules have been implicated in the development of OA; however, these have only been identified in the joint and serum. This study compared the expression of interleukin (IL-15) and Forkhead box protein-O1 (FoxO1) in muscle of patients with knee OA asymptomatic individuals, and examined whether IL-15 was also present in the joint and serum. Method Muscle and blood samples were collected from 19 patients with diagnosed knee OA and 10 age-matched asymptomatic individuals. Synovial fluid and muscle biopsies were collected from the OA group during knee replacement surgery. IL-15 and FoxO1were measured in the skeletal muscle. IL-15 abundance was also analysed in the serum of both groups and synovial fluid from the OA group. Knee extensor strength was measured and correlated with IL-15 and FoxO1 in the muscle. Results FoxO1 protein expression was higher (p=0.04), whereas IL-15 expression was lower (p=0.02) in the muscle of the OA group. Strength was also lower in the OA group, and was inversely correlated with FoxO1 expression. No correlation was found between IL-15 in the joint, muscle or serum. Conclusion Skeletal muscle, particularly the quadriceps, is affected in people with knee OA where elevated FoxO1 protein expression was associated with reduced muscle strength. While IL-15 protein expression in the muscle was lower in the knee OA group, no correlation was found between the expression of IL-15 protein in the muscle, joint and serum, which suggests that inflammation is regulated differently within these tissues.
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C17H19N302, monoclinic, P21, a = 5.382 (1), b = 17.534(4), c = 8.198(1)/L ,8 = 100.46(1) °, Z= 2, d,, = 1.323, dc= 1.299 Mg m-3, F(000) = 316, /~(Cu .Ka) = 0.618 mm -1. R = 0.052 for 1284 significant reflections. The proline-containing cispeptide unit which forms part of a six-membered ring deviates from perfect planarity. The torsion angle about the peptide bond is 3.0 (5) ° and the peptide bond length is 1.313 (5)A. The conformation of the proline ring is Cs-Cf~-endo. The crystal structure is stabilized by C-H... O interactions.
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Multiaction learning automata which update their action probabilities on the basis of the responses they get from an environment are considered in this paper. The automata update the probabilities according to whether the environment responds with a reward or a penalty. Learning automata are said to possess ergodicity of the mean if the mean action probability is the state probability (or unconditional probability) of an ergodic Markov chain. In an earlier paper [11] we considered the problem of a two-action learning automaton being ergodic in the mean (EM). The family of such automata was characterized completely by proving the necessary and sufficient conditions for automata to be EM. In this paper, we generalize the results of [11] and obtain necessary and sufficient conditions for the multiaction learning automaton to be EM. These conditions involve two families of probability updating functions. It is shown that for the automaton to be EM the two families must be linearly dependent. The vector defining the linear dependence is the only vector parameter which controls the rate of convergence of the automaton. Further, the technique for reducing the variance of the limiting distribution is discussed. Just as in the two-action case, it is shown that the set of absolutely expedient schemes and the set of schemes which possess ergodicity of the mean are mutually disjoint.
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The distribution of relative velocities between colliding particles in shear flows of inelastic spheres is analysed in the Volume fraction range 0.4-0.64. Particle interactions are considered to be due to instantaneous binary collisions, and the collision model has a normal coefficient of restitution e(n) (negative of the ratio of the post- and pre-collisional relative velocities of the particles along the line joining the centres) and a tangential coefficient of restitution e(t) (negative of the ratio of post- and pre-collisional velocities perpendicular to line joining the centres). The distribution or pre-collisional normal relative velocities (along the line Joining the centres of the particles) is Found to be an exponential distribution for particles with low normal coefficient of restitution in the range 0.6-0.7. This is in contrast to the Gaussian distribution for the normal relative velocity in all elastic fluid in the absence of shear. A composite distribution function, which consists of an exponential and a Gaussian component, is proposed to span the range of inelasticities considered here. In the case of roughd particles, the relative velocity tangential to the surfaces at contact is also evaluated, and it is found to be close to a Gaussian distribution even for highly inelastic particles.Empirical relations are formulated for the relative velocity distribution. These are used to calculate the collisional contributions to the pressure, shear stress and the energy dissipation rate in a shear flow. The results of the calculation were round to be in quantitative agreement with simulation results, even for low coefficients of restitution for which the predictions obtained using the Enskog approximation are in error by an order of magnitude. The results are also applied to the flow down an inclined plane, to predict the angle of repose and the variation of the volume fraction with angle of inclination. These results are also found to be in quantitative agreement with previous simulations.
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Purpose In many countries, both the number of older people in need of care and the number of employed caregivers of elderly relatives will increase over the next decades. The purpose of this paper is to examine the extent to which perceived organizational, supervisor, and coworker support for eldercare reduce employed caregivers’ strain and weaken the relationship between eldercare demands and strain. Design/methodology/approach Survey data were collected from 100 employed caregivers from one organization. Findings Results showed that eldercare demands were positively related to strain, and perceived organizational eldercare support (POES) was negatively related to strain. In addition, high POES weakened the relationship between eldercare demands and strain. Research limitations/implications The cross-sectional design and use of self-report scales constitute limitations of the study. Practical implications POES is a resource for employed caregivers, especially when their eldercare demands are high. Originality/value This research highlights the relative importance of different forms of perceived support for reducing employed caregivers’ strain and weakening the relationship between eldercare demands and strain.
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Career adaptability is a psychosocial construct that reflects individuals' resources for managing career tasks and challenges. This study investigated the effects of demographic characteristics and three sets of individual difference variables (Big Five personality traits, core self-evaluations, and temporal focus) on changes over time in career adaptability and its dimensions (concern, control, curiosity, and confidence). Data came from 659 full-time employees in Australia who participated in two measurement waves six months apart. Results showed that age and future temporal focus predicted change in overall career adaptability. In addition, age, education, extraversion, neuroticism, openness to experience, core self-evaluations, and future temporal focus differentially predicted change over time in one or more of the four career adaptability dimensions. While the lagged effects found in this study were generally small, the findings suggest that certain individual difference characteristics predispose employees to experience change in career adaptability over time.
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Childhood and education in Grodno and Lemberg; poor family background; active as soccer player; acting school of Max Reinhardt in Berlin; engagements in Munich, Zurich and Frankfurt; visit to Poland and short engagement with Yiddish theater troupe; description of theater in Weimar Germany; activities in "Juedischer Kulturbund" after 1933; main role in Kulturbund performance of "Nathan the Wise".
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* Plant response to drought is complex, so that traits adapted to a specific drought type can confer disadvantage in another drought type. Understanding which type(s) of drought to target is of prime importance for crop improvement. * Modelling was used to quantify seasonal drought patterns for a check variety across the Australian wheatbelt, using 123 yr of weather data for representative locations and managements. Two other genotypes were used to simulate the impact of maturity on drought pattern. * Four major environment types summarized the variability in drought pattern over time and space. Severe stress beginning before flowering was common (44% of occurrences), with (24%) or without (20%) relief during grain filling. High variability occurred from year to year, differing with geographical region. With few exceptions, all four environment types occurred in most seasons, for each location, management system and genotype. * Applications of such environment characterization are proposed to assist breeding and research to focus on germplasm, traits and genes of interest for target environments. The method was applied at a continental scale to highly variable environments and could be extended to other crops, to other drought-prone regions around the world, and to quantify potential changes in drought patterns under future climates.
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A method has been presented for constructing non-separable solutions of homogeneous linear partial differential equations of the type F(D, D′)W = 0, where D = ∂/∂x, D′ = ∂/∂y, Image where crs are constants and n stands for the order of the equation. The method has also been extended for equations of the form Φ(D, D′, D″)W = 0, where D = ∂/∂x, D′ = ∂/∂y, D″ = ∂/∂z and Image As illustration, the method has been applied to obtain nonseparable solutions of the two and three dimensional Helmholtz equations.
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A direct method of preparing cast aluminium alloy-graphite particle composites using uncoated graphite particles is reported. The method consists of introducing and dispersing uncoated but suitably pretreated graphite particles in aluminium alloy melts, and casting the resulting composite melts in suitable permanent moulds. The optical pretreatment required for the dispersion of the uncoated graphite particles in aluminium alloy melts consists of heating the graphite particles to 400° C in air for 1 h just prior to their dispersion in the melts. The effects of alloying elements such as Si, Cu and Mg on the dispersability of pretreated graphite in molten aluminium have also been reported. It was found that additions of about 0.5% Mg or 5% Si significantly improve the dispersability of graphite particles in aluminium alloy melts as indicated by the high recoveries of graphite in the castings of these composites. It was also possible to disperse upto 3% graphite in LM 13 alloy melts and retain the graphite particles in a well distributed fashion in the castings using the pre-heat-treated graphite particles. The observations in this study have been related to the information presently available on wetting between graphite and molten aluminium in the presence of different elements and our own thermogravimetric analysis studies on graphite particles. Physical and mechanical properties of LM 13-3% graphite composite made using pre-heat-treated graphite powder, were found to be adequate for many applications, including pistons which have been successfully used in internal combustion engines.
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Few-layer graphene films were grown by chemical vapor deposition and transferred onto n-type crystalline silicon wafers to fabricate graphene/n-silicon Schottky barrier solar cells. In order to increase the power conversion efficiency of such cells the graphene films were doped with nitric acid vapor and an antireflection treatment was implemented to reduce the sunlight reflection on the top of the device. The doping process increased the work function of the graphene film and had a beneficial effect on its conductivity. The deposition of a double antireflection coating led to an external quantum efficiency up to 90% across the visible and near infrared region, the highest ever reported for this type of devices. The combined effect of graphene doping and antireflection treatment allowed to reach a power conversion efficiency of 8.5% exceeding the pristine (undoped and uncoated) device performance by a factor of 4. The optical properties of the antireflection coating were found to be not affected by the exposure to nitric acid vapor and to remain stable over time.