Research suggests that inflammation may partially mediate the link between supportiveness of social relationships and physical health. However, cultural differences between Asians and European ...Americans in the nature of relationships and in seeking social support suggest that there may be cultural differences in the relation between supportive relationships and proinflammatory activity. One hundred and twenty-one young adult participants completed assessments of support from their close relationships (parents, romantic partner, and close friends) and provided oral mucosal transudate samples for assessment of the proinflammatory cytokines interleukin-6 (IL-6) and the type II soluble receptor for tumor necrosis factor-α (sTNFαRII). As predicted, more supportive relationships were related to lower levels of IL-6 among European Americans, but not among Asian Americans. There were no relations to sTNFαRII in either group. We conclude that associations between supportive relationships and inflammatory activity may differ in ways that reflect cultural differences in the construal of relationships and social support.
Antioxidant activity of some seaweed from the gulf of Thailand Boonchumi, W. (Chiang Mai Univ. (Thailand). Dept. of Biology); Peerapornpisal, Y. (Chiang Mai Univ. (Thailand). Dept. of Biology); Kanjanapothi, D. (Chiang Mai Univ. (Thailand). Dept. of Pharmacology) ...
International journal of agriculture and biology,
01/2011, Letnik:
13, Številka:
1
Journal Article
Recenzirano
Four species of seaweed, Sargassum binderi Sonder, Amphiroa sp., Turbinaria conoides (J. Agardh) Kuzting and Halimeda macroloba Decaisne, were collected from the Gulf of Thailand. Seaweeds were ...extracted with water or ethanol and examined for phenolic compounds and antioxidant activities by measuring the scavenging activity of both ABTS and DPPH radicals. In general, the aqueous extracts (AE) showed higher antioxidant activities and phenolic contents than ethanolic extracts (EE). Therefore, AE were chosen for three additional assays: superoxide anion scavenging assay, anti-lipid peroxidation in liver homogenate and reducing power. T. conoides extract showed the highest antioxidation activity in all assays. Therefore, the dried T. conoides had a potential to antioxidative agent in nutraceutical products.
High nucleation density and crystalline diamond films were deposited on a mirror-polished Si(100) substrate by horizontal microwave plasma chemical vapor deposition using a two step process ...consisting of positive direct current (dc) bias enhanced nucleation and growth. Optical emission spectroscopy was employed to investigate
in situ the plasma emission characterization during positive biasing process. Emission lines from the Balmer series of atomic hydrogen, molecular hydrogen, CH, C
2, and Ar were observed in the visible and ultraviolet ranges when CH
4, H
2, and Ar were used as the reactant gases. The dependence of plasma emission spectra on the deposition parameters, such as biasing voltage, methane concentration and working pressure was investigated. The relative concentrations of neutral atomic hydrogen were estimated by using the Ar emission at 750.4 nm as an actinometer. A significant variation in the emission intensity of the radicals was measured with a change in the biasing voltage. The correlation between the spectra of some species and the quality of diamond films was studied. The results show that CH and C
2 both were important precursor in the diamond deposition, while C
2 was associated with the presence of amorphous phase in the films during positive dc biasing process.
Context. Cosmic rays (CRs) can be studied through the galaxy-wide gamma-ray emission that they generate when propagating in the interstellar medium. The comparison of the diffuse signals from ...different systems may inform us about the key parameters in CR acceleration and transport. Aims. We aim to determine and compare the properties of the cosmic-ray-induced gamma-ray emission of several Local Group galaxies. Methods. We use 2 years of nearly continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to search for gamma-ray emission from M 31 and M 33. We compare the results with those for the Large Magellanic Cloud, the Small Magellanic Cloud, the Milky Way, and the starburst galaxies M 82 and NGC 253. Results. We detect a gamma-ray signal at 5σ significance in the energy range 200 MeV–20 GeV that is consistent with originating from M 31. The integral photon flux above 100 MeV amounts to (9.1 ± 1.9stat ± 1.0sys) × 10-9 ph cm-2 s-1. We find no evidence for emission from M 33 and derive an upper limit on the photon flux >100 MeV of 5.1 × 10-9 ph cm-2 s-1 (2σ). Comparing these results to the properties of other Local Group galaxies, we find indications of a correlation between star formation rate and gamma-ray luminosity that also holds for the starburst galaxies. Conclusions. The gamma-ray luminosity of M 31 is about half that of the Milky Way, which implies that the ratio between the average CR densities in M 31 and the Milky Way amounts to ξ = 0.35 ± 0.25. The observed correlation between gamma-ray luminosity and star formation rate suggests that the flux of M 33 is not far below the current upper limit from the LAT observations.
We report on the multiwavelength observations of the bright, long gamma-ray burst GRB 110731A, by the Fermi and Swift observatories, and by the MOA and GROND optical telescopes. The analysis of the ...prompt phase reveals that GRB 110731A shares many features with bright Large Area Telescope bursts observed by Fermi during the first three years on-orbit: a light curve with short time variability across the whole energy range during the prompt phase, delayed onset of the emission above 100 MeV, extra power-law component and temporally extended high-energy emission. In addition, this is the first GRB for which simultaneous GeV, X-ray, and optical data are available over multiple epochs beginning just after the trigger time and extending for more than 800 s, allowing temporal and spectral analysis in different epochs that favor emission from the forward shock in a wind-type medium. The observed temporally extended GeV emission is most likely part of the high-energy end of the afterglow emission. Both the single-zone pair transparency constraint for the prompt signal and the spectral and temporal analysis of the forward-shock afterglow emission independently lead to an estimate of the bulk Lorentz factor of the jet Gamma ~ 500-550.
How stress gets under the skin Ortiz, Manuel S; Willey, Joshua F; Chiang, Jessica J
Revista medíca de Chile
142, Številka:
6
Journal Article
Recenzirano
Odprti dostop
How psychological stress gets under the skin and contributes to increase the odds for the onset and progression of chronic diseases has been object of abundant research. In this literature review, ...evidence about the role that both acute (natural phenomenon, marital conflict, a social evaluative task) and chronic stress (stress at work, and the perception of being discriminated) as well as interpersonal stress have on physical health, is examined. Behavioral (lack of physical activity, smoking, lack of adherence) and physiological (dysregulation of the hypothalamic-pituitary-adrenal axis, sympathetic-adrenal-medullary axis, immune system and inflammatory response) mechanisms through which psychological stress may contribute to the onset and progression of cardiovascular disease (altering blood pressure, heart rate reactivity, hemoconcentration and pro-coagulation function), and two key processes involved in cancer progression (angiogenesis and metastasis) are discussed. Finally, how social support may moderate the association among psychological stress and physical health is described.
The purpose of this study is to compare the angular and spatial distributions of therapeutic-energy proton beams obtained from the FLUKA, GEANT4 and MCNP6 Monte Carlo codes. The Monte Carlo ...simulations of proton beams passing through two thin targets and a water phantom were investigated to compare the primary and secondary proton fluence distributions and dosimetric differences among these codes. The angular fluence distributions, central axis depth-dose profiles, and lateral distributions of the Bragg peak cross-field were calculated to compare the proton angular and spatial distributions and energy deposition. Benchmark verifications from three different Monte Carlo simulations could be used to evaluate the residual proton fluence for the mean range and to estimate the depth and lateral dose distributions and the characteristic depths and lengths along the central axis as the physical indices corresponding to the evaluation of treatment effectiveness.
The results showed a general agreement among codes, except that some deviations were found in the penumbra region. These calculated results are also particularly helpful for understanding primary and secondary proton components for stray radiation calculation and reference proton standard determination, as well as for determining lateral dose distribution performance in proton small-field dosimetry. By demonstrating these calculations, this work could serve as a guide to the recent field of Monte Carlo methods for therapeutic-energy protons.
•Monte Carlo simulation for angular & spatial distributions of therapeutic proton.•Thin targets and water phantom cases investigated using FLUKA, GEANT4 and MCNP6.•Comparing the primary and secondary proton fluences and dosimetric differences.•Inter-code discrepancies were found in the penumbra region.•Results of lateral dose distributions are useful in proton small-field dosimetry.
The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to detect photons with energies from asymptotically =20 MeV to >300 GeV. The pre-launch ...response functions of the LAT were determined through extensive Monte Carlo simulations and beam tests. The point-spread function (PSF) characterizing the angular distribution of reconstructed photons as a function of energy and geometry in the detector is determined here from two years of on-orbit data by examining the distributions of gamma rays from pulsars and active galactic nuclei (AGNs). Above 3 GeV, the PSF is found to be broader than the pre-launch PSF. We checked for dependence of the PSF on the class of gamma -ray source and observation epoch and found none. We also investigated several possible spatial models for pair-halo emission around BL Lac AGNs. We found no evidence for a component with spatial extension larger than the PSF and set upper limits on the amplitude of halo emission in stacked images of low- and high-redshift BL Lac AGNs and the TeV blazars 1ES0229 + 200 and 1ES0347-121.
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