2,926 research outputs found
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An investigation of the differential effects of two dimensions of spokesman credibility as they interact with consumer involvement with brand choice.
Complete genome sequence of BK polyomavirus subtype Ib-1 detected in a kidney transplant patient with BK viremia using shotgun sequencing
We report here the complete genome sequence of polyomavirus BK subtype Ib-1, isolate AR11, identified in urine from a human kidney transplant recipient with a clinical diagnosis of BK viremia. The AR11 isolate is closely related to reference strain human polyomavirus 1 isolate J2B-2 with 99% identity
Development of thermally formed glass optics for astronomical hard x-ray telescopes
The next major observational advance in hard X-ray/soft gamma-ray astrophysics will come with the implementation of telescopes capable of focusing 10-200 keV radiation. Focusing allows high signal-to-noise imaging and spectroscopic observations of many sources in this band for the first time. The recent development of depth-graded multilayer coatings has made the design of telescopes for this bandpass practical, however the ability to manufacture inexpensive substrates with appropriate surface quality and figure to achieve sub-arcminute performance has remained an elusive goal. In this paper, we report on new, thermally-formed glass micro-sheet optics capable of meeting the requirements of the next-generation of astronomical hard X-ray telescopes
W/SiC x-ray multilayers optimized for use above 100 keV
We have developed a new depth-graded multilayer system comprising W and SiC layers, suitable for use as hard x-ray reflective coatings operating in the energy range 100-200 keV. Grazing-incidence x-ray reflectance at E = 8 keV was used to characterize the interface widths, as well as the temporal and thermal stability in both periodic and depth-graded W/SiC structures, whereas synchrotron radiation was used to measure the hard x-ray reflectance of a depth-graded multilayer designed specifically for use in the range E ~150-170 keV. We have modeled the hard x-ray reflectance using newly derived optical constants, which we determined from reflectance versus incidence angle measurements also made using synchrotron radiation, in the range E = 120-180 keV. We describe our experimental investigation in detail, compare the new W/SiC multilayers with both W/Si and W/B4C films that have been studied previously, and discuss the significance of these results with regard to the eventual development of a hard x-ray nuclear line telescope
Using coupled micropillar compression and micro-Laue diffraction to investigate deformation mechanisms in a complex metallic alloy Al13Co4
In this investigation, we have used in-situ micro-Laue diffraction combined with micropillar compression of focused ion beam milled Al13Co4 complex metallic alloy to study the evolution of deformation in Al13Co4. Streaking of the Laue spots showed that the onset of plastic flow occured at stresses as low as 0.8 GPa, although macroscopic yield only becomes apparent at 2 GPa. The measured misorientations, obtained from peak splitting, enabled the geometrically necessary dislocation density to be estimated as 1.1 x 1013 m-2
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Subclinical myocardial disease by cardiac magnetic resonance imaging and spectroscopy in healthy HIV/Hepatitis C virus-coinfected persons.
Objective The contribution of hepatitis C virus (HCV) infection to the risk of heart failure in human immunodeficiency virus (HIV)-coinfected persons is unknown. The objective was to characterize cardiac function and morphology in HIV-treated coinfected persons. Methods In a cross-sectional study, HIV-infected patients virologically suppressed on antiretroviral therapy without known cardiovascular disease or diabetes mellitus underwent cardiac magnetic resonance imaging and spectroscopy for measures of cardiac function, myocardial fibrosis, and steatosis. Results The study included 18 male patients with a median age of 44 years. Of these, 10 had untreated HCV coinfection and eight had HIV monoinfection. Global systolic and diastolic function in the cohort were normal, and median myocardial fat content was 0.48% (interquartile range 0.35-1.54). Left ventricular (LV) mass index and LV mass/volume ratio were significantly greater in the HIV/HCV-coinfected group compared with the HIV-monoinfected group. In the HIV-monoinfected group, there was more myocardial fibrosis as measured by extracellular volume fraction. Conclusions There were differences between HIV/HCV-coinfected and HIV-monoinfected patients in cardiac structure and morphology. Larger studies are needed to examine whether HIV and HCV independently contribute to mechanisms of heart failure
First NuSTAR Limits on Quiet Sun Hard X-Ray Transient Events
We present the first results of a search for transient hard X-ray (HXR)
emission in the quiet solar corona with the \textit{Nuclear Spectroscopic
Telescope Array} (\textit{NuSTAR}) satellite. While \textit{NuSTAR} was
designed as an astrophysics mission, it can observe the Sun above 2~keV with
unprecedented sensitivity due to its pioneering use of focusing optics.
\textit{NuSTAR} first observed quiet Sun regions on 2014 November 1, although
out-of-view active regions contributed a notable amount of background in the
form of single-bounce (unfocused) X-rays. We conducted a search for quiet Sun
transient brightenings on time scales of 100 s and set upper limits on emission
in two energy bands. We set 2.5--4~keV limits on brightenings with time scales
of 100 s, expressed as the temperature T and emission measure EM of a thermal
plasma. We also set 10--20~keV limits on brightenings with time scales of 30,
60, and 100 s, expressed as model-independent photon fluxes. The limits in both
bands are well below previous HXR microflare detections, though not low enough
to detect events of equivalent T and EM as quiet Sun brightenings seen in soft
X-ray observations. We expect future observations during solar minimum to
increase the \textit{NuSTAR} sensitivity by over two orders of magnitude due to
higher instrument livetime and reduced solar background.Comment: 11 pages, 7 figures; accepted for publication in The Astrophysical
Journa
DNA repair biomarkers XPF and phospho-MAPKAP kinase 2 correlate with clinical outcome in advanced head and neck cancer.
BackgroundInduction chemotherapy is a common therapeutic option for patients with locoregionally-advanced head and neck cancer (HNC), but it remains unclear which patients will benefit. In this study, we searched for biomarkers predicting the response of patients with locoregionally-advanced HNC to induction chemotherapy by evaluating the expression pattern of DNA repair proteins.MethodsExpression of a panel of DNA-repair proteins in formalin-fixed paraffin embedded specimens from a cohort of 37 HNC patients undergoing platinum-based induction chemotherapy prior to definitive chemoradiation were analyzed using quantitative immunohistochemistry.ResultsWe found that XPF (an ERCC1 binding partner) and phospho-MAPKAP Kinase 2 (pMK2) are novel biomarkers for HNSCC patients undergoing platinum-based induction chemotherapy. Low XPF expression in HNSCC patients is associated with better response to induction chemoradiotherapy, while high XPF expression correlates with a worse response (pâ=â0.02). Furthermore, low pMK2 expression was found to correlate significantly with overall survival after induction plus chemoradiation therapy (pâ=â0.01), suggesting that pMK2 may relate to chemoradiation therapy.ConclusionsWe identified XPF and pMK2 as novel DNA-repair biomarkers for locoregionally-advanced HNC patients undergoing platinum-based induction chemotherapy prior to definitive chemoradiation. Our study provides insights for the use of DNA repair biomarkers in personalized diagnostics strategies. Further validation in a larger cohort is indicated
15 kDa Granulysin versus GM-CSF for monocytes differentiation: analogies and differences at the transcriptome level
<p>Abstract</p> <p>Background</p> <p>Granulysin is an antimicrobial and proinflammatory protein with several isoforms. While the 9 kDa isoform is a well described cytolytic molecule with pro-inflammatory activity, the functions of the 15 kDa isoform is less well understood. Recently it was shown that 15 kDa Granulysin can act as an alarmin that is able to activate monocytes and immature dendritic cells. Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) is a growth factor widely used in immunotherapy both for <it>in vivo </it>and <it>ex vivo </it>applications, especially for its proliferative effects.</p> <p>Methods</p> <p>We analyzed gene expression profiles of monocytes cultured with 15 kDa Granulysin or GM-CSF for 4, 12, 24 and 48 hours to unravel both similarities and differences between the effects of these stimulators.</p> <p>Results</p> <p>The analysis revealed a common signature induced by both factors at each time point, but over time, a more specific signature for each factor became evident. At all time points, 15 kDa Granulysin induced immune response, chemotaxis and cell adhesion genes. In addition, only 15 kDa Granulsyin induced the activation of pathways related to fundamental dendritic cell functions, such as co-stimulation of T-cell activation and Th1 development. GM-CSF specifically down-regulated genes related to cell cycle arrest and the immune response. More specifically, cytokine production, lymphocyte mediated immunity and humoral immune response were down-regulated at late time points.</p> <p>Conclusion</p> <p>This study provides important insights on the effects of a novel agent, 15 kDa granulysin, that holds promise for therapeutic applications aimed at the activation of the immune response.</p
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