7,246 research outputs found
Emerging key roles for P2X receptors in the kidney
P2X ionotropic non-selective cation channels are expressed throughout the kidney and are activated in a paracrine or autocrine manner following the binding of extracellular ATP and related extracellular nucleotides. Whilst there is a wealth of literature describing a regulatory role of P2 receptors (P2R) in the kidney, there are significantly less data on the regulatory role of P2X receptors (P2XR) compared with that described for metabotropic P2Y. Much of the historical literature describing a role for P2XR in the kidney has focused heavily on the role of P2X1R in the autoregulation of renal blood flow. More recently, however, there has been a plethora of manuscripts providing compelling evidence for additional roles for P2XR in both kidney health and disease. This review summarizes the current evidence for the involvement of P2XR in the regulation of renal tubular and vascular function, and highlights the novel data describing their putative roles in regulating physiological and pathophysiological processes in the kidney
Can fundamental movement skill mastery be increased via a six week physical activity intervention to have positive effects on physical activity and physical self-perception?
Previous research has suggested a positive relationship between fundamental movement skills (FMS) mastery and physical activity (PA) level. Research conducted on interventions to improve FMS mastery is equivocal and further research is needed.An intervention group of 82 children (35 boys and 47 girls) and a control group of 83 children (42 boys and 41 girls) were recruited from Years 4 and 5 (mean age ± SD = 8.3 ± 0.4 years) of two schools in Central England. The intervention included a combination of circuits and dancing to music. Pre and post intervention tests were conducted. Tests included: subjective assessment of eight FMS; objective measurement of two FMS; four day pedometer step count recording; height and mass for Body Mass Index (BMI); and the completion of Harter et al.'s (1982) self-perception questionnaire.Following a two (pre to post) by two (intervention and control group) mixed-model ANOVA it was highlighted that the intervention group improved mastery in all eight FMS, and increased both daily steps and physical self-perception.It can be concluded that focussing one Physical Education (PE) lesson per week on the development of FMS has had a positive benefit on FMS, PA level and physical self-perception for the children in this study
Birth, death and diffusion of interacting particles
Individual-based models of chemical or biological dynamics usually consider
individual entities diffusing in space and performing a birth-death type
dynamics. In this work we study the properties of a model in this class where
the birth dynamics is mediated by the local, within a given distance, density
of particles. Groups of individuals are formed in the system and in this paper
we concentrate on the study of the properties of these clusters (lifetime,
size, and collective diffusion). In particular, in the limit of the interaction
distance approaching the system size, a unique cluster appears which helps to
understand and characterize the clustering dynamics of the model.Comment: 15 pages, 6 figures, Iop style. To appear in Journal of Physics A:
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High Pressure Effects on Thermal Properties of MgO
Using the non-empirical Variational Induced Breathing (VIB) model, the
thermal properties of periclase (MgO) under high pressures and temperatures are
investigated using molecular dynamics, which includes all anharmonic effects.
Equations of state for temperatures up to 3000K and pressures up to 310 GPa
were calculated. Bulk modulus, thermal expansivity, Anderson-Gruneisen
parameter, thermal pressure, Gruneisen parameter and their pressure and
temperature dependencies are studied in order to better understand high
pressure effects on thermal properties. The results agree very well with
experiments and show that the thermal expansivity decreases with pressure up to
about 100 GPa (=0.73), and is almost pressure and temperature independent
above this compression. It is also effected by anharmonicity at zero pressure
and temperatures above 2500K. The thermal pressure changes very little with
increasing pressures and temperatures, and the Gruneisen parameter is
temperature independent and decreases slightly with pressure.Comment: Geophys. Res. Lett., in press, 7 pages, 4 figures, uuencoded ps fil
Refractive Index of Humid Air in the Infrared: Model Fits
The theory of summation of electromagnetic line transitions is used to
tabulate the Taylor expansion of the refractive index of humid air over the
basic independent parameters (temperature, pressure, humidity, wavelength) in
five separate infrared regions from the H to the Q band at a fixed percentage
of Carbon Dioxide. These are least-squares fits to raw, highly resolved spectra
for a set of temperatures from 10 to 25 C, a set of pressures from 500 to 1023
hPa, and a set of relative humidities from 5 to 60%. These choices reflect the
prospective application to characterize ambient air at mountain altitudes of
astronomical telescopes.Comment: Corrected exponents of c0ref, c1ref and c1p in Table
Caution is required in the implementation of 90-day mortality indicators for radiotherapy in a curative setting: A retrospective population-based analysis of over 16,000 episodes
Background: 90-day mortality (90DM) has been proposed as a clinical indicator in radiotherapy delivered in a curative setting. No large scale assessment has been made. Its value in allowing robust comparisons between centres and facilitating service improvement is unknown. Methods: All radiotherapy treatments delivered in a curative setting over seven years were extracted from the local electronic health record and linked to cancer registry data. 90DM rates were assessed and factors associated with this outcome were investigated using logistic regression. Cause of death was identified retrospectively further characterising the cause of 90DM. Results: Overall 90DM was 1.25%. Levels varied widely with diagnosis (0.20%-5.45%). Age (OR 1.066, 1.043-1.073), year of treatment (OR 0.900, 0.841-0.969) and diagnosis were significantly associated with 90DM on multi-variable logistic regression. Cause of death varied with diagnosis; 50.0% post-operative in rectal cancer, 40.4% treatment-related in head and neck cancer, 59.4% disease progression in lung cancer. Conclusion: Despite the drive to report centre level comparative outcomes, this study demonstrates that 90DM cannot be adopted routinely as a clinical indicator due to significant population heterogeneity and low event rates. Further national investigation is needed to develop a meaningful robust indicator that delivers appropriate comparisons and drive improvements in care
Electronic structure investigation of the cubic inverse perovskite Sc3AlN
The electronic structure and chemical bonding of the recently discovered
inverse perovskite Sc3AlN, in comparison to ScN and Sc metal have been
investigated by bulk-sensitive soft x-ray emission spectroscopy. The measured
Sc L, N K, Al L1, and Al L2,3 emission spectra are compared with calculated
spectra using first principle density-functional theory including dipole
transition matrix elements. The main Sc 3d - N 2p and Sc 3d - Al 3p chemical
bond regions are identified at -4 eV and -1.4 eV below the Fermi level,
respectively. A strongly modified spectral shape of 3s states in the Al L2,3
emission from Sc3AlN in comparison to pure Al metal is found, which reflects
the Sc 3d - Al 3p hybridization observed in the Al L1 emission. The differences
between the electronic structure of Sc3AlN, ScN, and Sc metal are discussed in
relation to the change of the conductivity and elastic properties.Comment: 11 pages, 5 picture
How universal is the fractional-quantum-Hall edge Luttinger liquid?
This article reports on our microscopic investigations of the edge of the
fractional quantum Hall state at filling factor . We show that the
interaction dependence of the wave function is well described in an
approximation that includes mixing with higher composite-fermion Landau levels
in the lowest order. We then proceed to calculate the equal time edge Green
function, which provides evidence that the Luttinger exponent characterizing
the decay of the Green function at long distances is interaction dependent. The
relevance of this result to tunneling experiments is discussed.Comment: 5 page
The effects of booster sessions on self-management interventions for chronic musculoskeletal pain: a systematic review and meta-analysis of randomised controlled trials
Our objective was to investigate the effectiveness of booster sessions after self-management interventions as a means of maintaining self-management behaviours in the treatment of chronic musculoskeletal pain. We searched MEDLINE, EMBASE, Science Citation Index, Cochrane Central Register of Controlled Trials and PsycINFO. Two authors independently identified eligible trials and collected data. We calculated the odds ratio (OR) for the analyses of dichotomous data, and standardised mean differences (SMD) with 95% confidence interval (CI) for continuous variables. Our search identified 14 studies with a total of 1695 patients. All studies were at high risk of bias and provided very low quality evidence. For the primary outcomes, booster sessions had no evidence of an effect on improving patient-reported outcomes on physical function (SMD-0.13, 95%CI -0.32 to -0.06; P=0.18), pain-related disability (SMD-0.16, 95%CI -0.36 to 0.03; P=0.11) and pain self-efficacy (SMD 0.15, 95%CI -0.07 to 0.36; P=0.18). For the secondary outcomes, booster sessions caused a significant reduction in patient-reported pain catastrophising (SMD-0.42, 95%CI -0.64 to -0.19; P=0.0004), and no evidence of an effect on patient-reported pain intensity, depression, coping or treatment adherence. There is currently little evidence that booster sessions are an effective way to prolong positive treatment effects or improve symptoms of long-term musculoskeletal conditions following self-management interventions. However, the studies were few with high heterogeneity, high risk of bias and overall low quality of evidence. Our review argues against including booster sessions routinely to self-management interventions for the purpose of behaviour maintenance
The Role of Habit, Childhood Consumption, Familiarity and Attitudes Across Seafood Consumption Segments in Australia
Australian consumers hold very favorable attitudes toward seafood, with key drivers to consumption being taste, convenience, diet variety, and health benefits. Nevertheless, despite these positive attitudes, seafood consumption remains below many other countries. In this article, we investigate the influence of habit including regular childhood consumption, familiarity with seafood, and attitudes toward seafood on seafood consumption and consumption occasions. Habit and lack of familiarity with seafood were found to lead to lower levels of seafood consumption, whereas positive attitudes toward seafood were associated with more regular seafood consumption. People who consumed seafood on a regular basis as a child were more likely to be more familiar with seafood and be in the habit of consuming seafood in adulthood. Patterns of childhood consumption occasions were found to be associated with adult consumption occasions. Based on these findings, we discuss possible strategies and behavioral interventions for further investigation, which are grounded in habit theory and are aimed at changing seafood eating habits, increasing childhood consumption, and reducing the lack of familiarity with seafood
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