1,923 research outputs found

    X-ray Emitting GHz-Peaked Spectrum Galaxies: Testing a Dynamical-Radiative Model with Broad-Band Spectra

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    In a dynamical-radiative model we recently developed to describe the physics of compact, GHz-Peaked-Spectrum (GPS) sources, the relativistic jets propagate across the inner, kpc-sized region of the host galaxy, while the electron population of the expanding lobes evolves and emits synchrotron and inverse-Compton (IC) radiation. Interstellar-medium gas clouds engulfed by the expanding lobes, and photoionized by the active nucleus, are responsible for the radio spectral turnover through free-free absorption (FFA) of the synchrotron photons. The model provides a description of the evolution of the spectral energy distribution (SED) of GPS sources with their expansion, predicting significant and complex high-energy emission, from the X-ray to the gamma-ray frequency domain. Here, we test this model with the broad-band SEDs of a sample of eleven X-ray emitting GPS galaxies with Compact-Symmetric-Object (CSO) morphology, and show that: (i) the shape of the radio continuum at frequencies lower than the spectral turnover is indeed well accounted for by the FFA mechanism; (ii) the observed X-ray spectra can be interpreted as non-thermal radiation produced via IC scattering of the local radiation fields off the lobe particles, providing a viable alternative to the thermal, accretion-disk dominated scenario. We also show that the relation between the hydrogen column densities derived from the X-ray (N_H) and radio (N_HI) data of the sources is suggestive of a positive correlation, which, if confirmed by future observations, would provide further support to our scenario of high-energy emitting lobes.Comment: 29 pages, 3 figures, 6 tables; to appear in ApJ. A few clarifications included, according to referee's suggestion

    Evaluating PET-CT in the detection and management of recurrent cervical cancer: Systematic reviews of diagnostic accuracy and subjective elicitation

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    Background: Positron emission tomography-computed tomography (PET-CT) is recommended to triage women for exenterative surgery and surveillance after treatment for advanced cervical cancer. Objective: To evaluate diagnostic accuracy of additional whole body PET-CT compared with CT/magnetic resonance imaging (MRI) alone in women with suspected recurrent/persistent cervical cancer and in asymptomatic women as surveillance. Design: Systematic reviews. Subjective elicitation to supplement diagnostic information. Search strategy/Selection criteria/Data collection and analysis: Searches of electronic databases were performed to June 2013. Studies in women with suspected recurrent/persistent cervical cancer and in asymptomatic women undergoing follow up with sufficient numeric data were included. We calculated sensitivity, specificity and corresponding 95% confidence intervals. Meta-analyses employed a bivariate model that included a random-effects term for between-study variations (CT studies) and univariate random effects meta-analyses (PET-CT studies) for sensitivity and specificity separately. Subjective elicitation: Prevalence of recurrence and the accuracy of imaging elicited using the allocation of points technique. Coherence of elicited subjective probabilities with estimates in the literature examined. Results: We identified 15 relevant studies; none directly compared additional PET-CT with MRI or CT separately. Most CT and MRI studies used older protocols and the majority did not distinguish between asymptomatic and symptomatic women. Meta-analysis of nine PET-CT studies in mostly symptomatic women showed sensitivity of 94.8 (95% CI 91.2-96.9), and specificity of 86.9% (95% CI 82.2-90.5). The summary estimate of the sensitivity of CT for detection of recurrence was 89.64% (95% CI 81.59-94.41) and specificity was 76% (95% CI 43.68-92.82). Meta-analysis for MRI test accuracy studies was not possible because of clinical heterogeneity. The sensitivity and specificity of MRI in pelvic recurrence varied between 82 and 100% and between 78 and 100%, respectively. Formal statistical comparisons of the accuracy of index tests were not possible. Subjective elicitation provided estimates comparable to the literature. Subjective estimates of the increase in accuracy from the addition of PET-CT were less than elicited increases required to justify the use in PET-CT for surveillance. Conclusion: Evidence to support additional PET-CT is scarce, of average quality and does not distinguish between application for surveillance and diagnosis. Guidelines recommending PET-CT in recurrent cervical cancer need to be reconsidered in the light of the existing evidence base

    Positron emission tomography/computerised tomography imaging in detecting and managing recurrent cervical cancer: systematic review of evidence, elicitation of subjective probabilities and economic modelling.

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    © Queen’s Printer and Controller of HMSO 2013. This work was produced by Meads et al. under the terms of a commissioning contract issued by the Secretary of State for Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising.Cancer of the uterine cervix is a common cause of mortality in women. After initial treatment women may be symptom free, but the cancer may recur within a few years. It is uncertain whether it is more clinically effective to survey asymptomatic women for signs of recurrence or to await symptoms or signs before using imaging.National Institute for Health Research Health Technology Assessment programm

    The flow direction of interstellar neutral H from SOHO/SWAN

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    Interstellar neutral hydrogen flows into the heliosphere as a mixture of the primary and secondary populations from two somewhat different directions due to splitting occurring in the magnetized outer heliosheath. The direction of inflow of interstellar neutral H observed in the inner heliosphere, confronted with that of the unperturbed flow of interstellar neutral helium, is important for understanding the geometry of the distortion of the heliosphere from axial symmetry. It is also needed for facilitating remote-sensing studies of the solar wind structure based on observations of the helioglow, such as those presently performed by SOHO/SWAN, and in a near future by IMAP/GLOWS. In the past, the only means to measure the flow direction of interstellar hydrogen were spectroscopic observations of the helioglow. Here, we propose a new method to determine this parameter based on a long series of photometric observations of the helioglow. The method is based on purely geometric considerations and does not depend on any model and absolute calibration of the measurements. We apply this method to sky maps of the helioglow available from the SOHO/SWAN experiment and derive the mean flow longitude of interstellar hydrogen. We obtain 253.1\degr \pm 2.8\degr, which is in perfect agreement with the previously obtained results based on spectroscopic observations.Comment: Accepted for Ap

    Isomer shift and magnetic moment of the long-lived 1/2+^{+} isomer in 3079^{79}_{30}Zn49_{49}: signature of shape coexistence near 78^{78}Ni

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    Collinear laser spectroscopy has been performed on the 3079^{79}_{30}Zn49_{49} isotope at ISOLDE-CERN. The existence of a long-lived isomer with a few hundred milliseconds half-life was confirmed, and the nuclear spins and moments of the ground and isomeric states in 79^{79}Zn as well as the isomer shift were measured. From the observed hyperfine structures, spins I=9/2I = 9/2 and I=1/2I = 1/2 are firmly assigned to the ground and isomeric states. The magnetic moment μ\mu (79^{79}Zn) = -1.1866(10) μN\mu_{\rm{N}}, confirms the spin-parity 9/2+9/2^{+} with a νg9/21\nu g_{9/2}^{-1} shell-model configuration, in excellent agreement with the prediction from large scale shell-model theories. The magnetic moment μ\mu (79m^{79m}Zn) = -1.0180(12) μN\mu_{\rm{N}} supports a positive parity for the isomer, with a wave function dominated by a 2h-1p neutron excitation across the N=50N = 50 shell gap. The large isomer shift reveals an increase of the intruder isomer mean square charge radius with respect to that of the ground state: δrc279,79m\delta \langle r^{2}_{c}\rangle^{79,79m} = +0.204(6) fm2^{2}, providing first evidence of shape coexistence.Comment: 5 pages, 4 figures, 1 table, Accepeted by Phys. Rev. Lett. (2016

    Chemical composition of atherosclerotic plaques of apoE/LDLR-double knockout mice by synchrotron radiation FTIR microspectroscopy

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    Atherosclerosis is a multietiological inflammatory disease of large and medium-sized arteries of increasing incidence in westernized countries. The aim of this study was to identify the biochemical changes during the progression of atherosclerosis by synchrotron radiation Fourier transform infrared microspectroscopy in atheromas of apoE/LDLR//LDLR^{-//-} mice fed egg-rich diet supplemented or not with angiotensin converting enzyme inhibitor perindopril. Synchrotron radiation Fourier transform infrared microspectroscopy technique was used to obtain information at high spatial resolution about the distribution of proteins (C-N, N-H, CO for amide I and amide II bands), lipids (CH2CH_2, CH3CH_3 bands) as well as mineral deposits (calcium carbonates and phosphates). Total contents of lipids and proteins were found to be significantly lower in animals treated with the diet and perindopril. An increase in saturation level of lipids was observed in animals fed with egg-rich diet when compared to the normal diet and perindopril treatment, which did not inhibit this effect. Moreover, a significant change in the secondary structure of proteins (ratio between absorption bands 1634 cm1cm^{-1}/1656 cm1cm^{-1} attributed to β-type and α-type, respectively) was observed in both experimental groups in comparison with the control. Principal component analysis was used to analyse the recorded spectra. It has revealed that higher content of phosphates (wavenumber range 950-1020 cm1cm^{-1}) was observed between egg-rich diet fed animals and the control group

    Probing the N = 32 shell closure below the magic proton number Z = 20: Mass measurements of the exotic isotopes 52,53K

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    The recently confirmed neutron-shell closure at N = 32 has been investigated for the first time below the magic proton number Z = 20 with mass measurements of the exotic isotopes 52,53K, the latter being the shortest-lived nuclide investigated at the online mass spectrometer ISOLTRAP. The resulting two-neutron separation energies reveal a 3 MeV shell gap at N = 32, slightly lower than for 52Ca, highlighting the doubly-magic nature of this nuclide. Skyrme-Hartree-Fock-Boguliubov and ab initio Gorkov-Green function calculations are challenged by the new measurements but reproduce qualitatively the observed shell effect.Comment: 5 pages, 5 figure

    Особенности художественного отображения агрессии, направленной против Азербайджана

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    [EN]: The micromammals remains from the Late Pleistocene site of the cave of El Castillo studied here in detail, came from the Aurignacian levels 18b and 18c (dated in 40.000-45.000 BP), level 19, and the Musterian levels 20b, 20c, 20d, 20e (dated in 41.000-49.000 BP), 21a and 21b. The micromammal association is the following: Erinaceus europaeus, Crocidura russula, Sorex coronatus, Sorex minutus, Neomys fodiens, Talpa europaea, Galemys pyrenaicus, cf. Miniopterus schreibersii, Chiroptera indet., Pliomys lenki, Microtus arvalis – Microtus agrestis, Microtus lusitanicus, Microtus oeconomus, Chionomys nivalis, Arvicola terrestris, Apodemus sylvaticus – Apodemus flavicollis and Lepus sp. Most of these species are in the present fauna of Cantabria, except Pliomys lenki that got extinct in the last third of the Upper Pleistocene, and Microtus oeconomus that disappeared from the Iberian Peninsula during the Holocene, in historical times, and is nowadays present in northern Euroasiatic regions. There is a great continuity of most of the taxa in all the levels. The faunal association seems to indicate a mainly open environment, in general with wet meadows (and few dry meadows), with good vegetation cover in the soil, with perhaps also some tree-covered areas, and some watercourses. The thermophiles indicators are very scarce, which could indicate that the climate could be a lesser temperate than other Upper Pleistocene periods and the present-day climate in the area.[ES]: El material de micromamíferos del yacimiento del Pleistoceno Superior de la cueva de El Castillo, objeto de estudio detallado en este trabajo, proviene de los niveles auriñacienses 18b y 18c (datados en 40.000-45.000 BP), nivel 19, y niveles musterienses 20b, 20c, 20d, 20e (datados en 41.000-49.000 BP), 21a y 21b. La asociación de micromamíferos es la siguiente: Erinaceus europaeus, Crocidura russula, Sorex coronatus, Sorex minutus, Neomys fodiens, Talpa europaea, Galemys pyrenaicus, cf. Miniopterus schreibersii, Chiroptera indet., Pliomys lenki, Microtus arvalis – Microtus agrestis, Microtus lusitanicus, Microtus oeconomus, Chionomys nivalis, Arvicola terrestris, Apodemus sylvaticus – Apodemus flavicollis y Lepus sp. La mayoría de estas especies están presentes en la fauna actual de Cantabria, excepto Pliomys lenki que se extinguió en el último tercio del Pleistoceno Superior, y Microtus oeconomus, que persistió en la península ibérica durante el Holoceno bien avanzado hasta su desaparición en tiempos históricos, y que actualmente está en regiones euroasiáticas más septentrionales. Hay una gran continuidad de la gran mayoría de los taxones en todos los niveles. La fauna en su conjunto parece indicar un medio predominantemente abierto, por lo general de praderas húmedas (y en mucha menor medida praderas secas) con una buena cobertura vegetal a nivel del suelo, en el que habría también algunas zonas arboladas o boscosas, y algún curso de agua. Los indicadores termófilos son escasos y poco abundantes, lo que podría indicar que el clima podría ser algo menos templado que en otros periodos del Pleistoceno Superior y quizás también que actualmente en la zona.Peer Reviewe

    The Role of Platelet Factor 4 in Local and Remote Tissue Damage in a Mouse Model of Mesenteric Ischemia/Reperfusion Injury

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    The robust inflammatory response that occurs during ischemia reperfusion (IR) injury recruits factors from both the innate and adaptive immune systems. However the contribution of platelets and their products such as Platelet Factor 4 (PF4; CXCL4), during the pathogenesis of IR injury has not been thoroughly investigated. We show that a deficiency in PF4 protects mice from local and remote tissue damage after 30 minutes of mesenteric ischemia and 3 hours of reperfusion in PF4-/- mice compared to control B6 mice. This protection was independent from Ig or complement deposition in the tissues. However, neutrophil and monocyte infiltration were decreased in the lungs of PF4-/- mice compared with B6 control mice. Platelet-depleted B6 mice transfused with platelets from PF4-/- mice displayed reduced tissue damage compared with controls. In contrast, transfusion of B6 platelets into platelet depleted PF4-/- mice reconstituted damage in both intestine and lung tissues. We also show that PF4 may modulate the release of IgA. Interestingly, we show that PF4 expression on intestinal epithelial cells is increased after IR at both the mRNA and protein levels. In conclusion, these findings demonstrate that may PF4 represent an important mediator of local and remote tissue damage

    Impact of FTO genotypes on BMI and weight in polycystic ovary syndrome : a systematic review and meta-analysis

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    Aims/hypothesis FTO gene single nucleotide polymorphisms (SNPs) have been shown to be associated with obesity-related traits and type 2 diabetes. Several small studies have suggested a greater than expected effect of the FTO rs9939609 SNP on weight in polycystic ovary syndrome (PCOS). We therefore aimed to examine the impact of FTO genotype on BMI and weight in PCOS. Methods A systematic search of medical databases (PubMed, EMBASE and Cochrane CENTRAL) was conducted up to the end of April 2011. Seven studies describing eight distinct PCOS cohorts were retrieved; seven were genotyped for SNP rs9939609 and one for SNP rs1421085. The per allele effect on BMI and body weight increase was calculated and subjected to meta-analysis. Results A total of 2,548 women with PCOS were included in the study; 762 were TT homozygotes, 1,253 had an AT/CT genotype, and 533 were AA/CC homozygotes. Each additional copy of the effect allele (A/C) increased the BMI by a mean of 0.19 z score units (95% CI 0.13, 0.24; p = 2.26 × 10−11) and body weight by a mean of 0.20 z score units (95% CI 0.14, 0.26; p = 1.02 × 10−10). This translated into an approximately 3.3 kg/m2 increase in BMI and an approximately 9.6 kg gain in body weight between TT and AA/CC homozygotes. The association between FTO genotypes and BMI was stronger in the cohorts with PCOS than in the general female populations from large genome-wide association studies. Deviation from an additive genetic model was observed in heavier populations. Conclusions/interpretation The effect of FTO SNPs on obesity-related traits in PCOS seems to be more than two times greater than the effect found in large population-based studies. This suggests an interaction between FTO and the metabolic context or polygenic background of PCOS
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