325 research outputs found

    Mantle wedge temperatures and their potential relation to volcanic arc location

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    The mechanisms underpinning the formation of a focused volcanic arc above subduction zones are debated. Suggestions include controls by: (i) where the subducting plate releases water, lowering the solidus in the overlying mantle wedge; (ii) the location where the mantle wedge melts to the highest degree; and (iii) a limit on melt formation and migration imposed by the cool shallow corner of the wedge. Here, we evaluate these three proposed mechanisms using a set of kinematically-driven 2D thermo-mechanical mantle-wedge models in which subduction velocity, slab dip and age, overriding-plate thickness and the depth of decoupling between the two plates are systematically varied. All mechanisms predict, on the basis of model geometry, that the arc-trench distance, D, decreases strongly with increasing dip, consistent with the negative D-dip correlations found in global subduction data. Model trends of sub-arc slab depth, H, with dip are positive if H is wedge-temperature controlled and overriding-plate thickness does not exceed the decoupling depth by more than 50 km, and negative if H is slab-temperature controlled. Observed global H-dip trends are overall positive. With increasing overriding plate thickness, the position of maximum melting shifts to smaller H and D, while the position of the trenchward limit of the melt zone, controlled by the wedge's cold corner, shifts to larger H and D, similar to the trend in the data for oceanic subduction zones. Thus, the limit imposed by the wedge corner on melting and melt migration seems to exert the first-order control on arc position

    Reduction of myocardial infarction by postischemic administration of the calpain inhibitor A-705253 in comparison to the Na(+)/H(+) exchange inhibitor Cariporide (R) in isolated perfused rabbit hearts

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    The calpain inhibitor A-705253 and the Na(+)/H(+) exchange inhibitor Cariporide (R) were studied in isolated perfused rabbit hearts subjected to 60 min occlusion of the ramus interventricularis of the left coronary artery (below the origin of the first diagonal branch), followed by 120 min of reperfusion. The inhibitors were added to the perfusion fluid solely or in combination at the beginning of reperfusion. Hemodynamic monitoring and biochemical analysis of perfusion fluid from the coronary outflow were performed. Myocardial infarct size and area at risk (transiently not perfused myocardium) were determined from left ventricular slices after a special staining procedure with Evans blue and 2,3,5-triphenyltetrazolium chloride. The infarcted area (dead myocardium) was 72.7 +/- 4.0% of the area at risk in untreated controls, but was significantly smaller in the presence of the inhibitors. The largest effect was observed with 10(-6) M A-705253, which reduced the infarcted area to 49.2 +/- 4.1% of the area at risk, corresponding to a reduction of 33.6%. Cariporide (R) at 10(-6) M reduced the infarct size to the same extent. The combination of both inhibitors, however, did not further improve cardioprotection. No significant difference was observed between the experimental groups in coronary perfusion, left ventricular pressure, heart rate, or in the release of lactate dehydrogenase and creatine kinase from heart muscle

    High-contrast imaging constraints on gas giant planet formation - The Herbig Ae/Be star opportunity

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    Planet formation studies are often focused on solar-type stars, implicitly considering our Sun as reference point. This approach overlooks, however, that Herbig Ae/Be stars are in some sense much better targets to study planet formation processes empirically, with their disks generally being larger, brighter and simply easier to observe across a large wavelength range. In addition, massive gas giant planets have been found on wide orbits around early type stars, triggering the question if these objects did indeed form there and, if so, by what process. In the following I briefly review what we currently know about the occurrence rate of planets around intermediate mass stars, before discussing recent results from Herbig Ae/Be stars in the context of planet formation. The main emphasis is put on spatially resolved polarized light images of potentially planet forming disks and how these images - in combination with other data - can be used to empirically constrain (parts of) the planet formation process. Of particular interest are two objects, HD100546 and HD169142, where, in addition to intriguing morphological structures in the disks, direct observational evidence for (very) young planets has been reported. I conclude with an outlook, what further progress we can expect in the very near future with the next generation of high-contrast imagers at 8-m class telescopes and their synergies with ALMA.Comment: Accepted by Astrophysics and Space Science as invited short review in special issue about Herbig Ae/Be stars; 12 pages incl. 5 figures, 2 tables and reference

    Bulk micromegas detectors for large TPC applications

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    A large volume TPC will be used in the near future in a variety of experiments including T2K. The bulk Micromegas detector for this TPC is built using a novel production technique particularly suited for compact and robust low mass detectors. The capability to pave a large surface with a simple mounting solution and small dead space between modules is of particular interest for these applications. We have built several large bulk Micromegas detectors (27 x 26 cm2) and we have tested them in the former HARP field cage setup with a magnetic field. Cosmic ray data have been acquired in a variety of experimental conditions. Good detector performances and space point resolution have been achieved

    Analysis of the modes of energy consumption of the complex of an incoherent scattering of the institute of ionosphere of national academy of sciences and the ministry of education and science of Ukraine

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    ĐŁ ĐŽĐ°ĐœŃ–Đč статті прДЎстаĐČĐ»Đ”ĐœŃ– Ń€Đ”Đ·ŃƒĐ»ŃŒŃ‚Đ°Ń‚Đž Đ°ĐœĐ°Đ»Ń–Đ·Ńƒ Ń€Đ”Đ¶ĐžĐŒŃ–ĐČ Đ”ĐœĐ”Ń€ĐłĐŸŃĐżĐŸĐ¶ĐžĐČĐ°ĐœĐœŃ ĐșĐŸĐŒĐżĐ»Đ”Đșсу ĐœĐ”ĐșĐŸĐłĐ”Ń€Đ”ĐœŃ‚ĐœĐŸĐłĐŸ Ń€ĐŸĐ·ŃŃ–ŃĐœĐœŃ Đ†ĐœŃŃ‚ĐžŃ‚ŃƒŃ‚Ńƒ Ń–ĐŸĐœĐŸŃŃ„Đ”Ń€Đž НАН і МОН ĐŁĐșŃ€Đ°Ń—ĐœĐž Đ· ĐŒĐ”Ń‚ĐŸŃŽ ĐČĐžŃ€Ń–ŃˆĐ”ĐœĐœŃ ĐżŃ€ĐŸĐ±Đ»Đ”ĐŒĐž піЮĐČĐžŃ‰Đ”ĐœĐœŃ Đ”ĐœĐ”Ń€ĐłĐŸĐ”Ń„Đ”ĐșтоĐČĐœĐŸŃŃ‚Ń– ĐœĐ°ŃƒĐșĐŸĐČĐŸ-ĐŽĐŸŃĐ»Ń–ĐŽĐœĐŸĐłĐŸ ĐșĐŸĐŒĐżĐ»Đ”Đșсу та стĐČĐŸŃ€Đ”ĐœĐœŃ Đ”ĐœĐ”Ń€ĐłĐŸĐ”Ń„Đ”ĐșтоĐČĐœĐŸŃ— ŃĐžŃŃ‚Đ”ĐŒĐž ДлДĐșŃ‚Ń€ĐŸĐżĐŸŃŃ‚Đ°Ń‡Đ°ĐœĐœŃ, яĐșĐ° Đ·Đ°Đ±Đ”Đ·ĐżĐ”Ń‡ĐžŃ‚ŃŒ стіĐčĐșу Ń€ĐŸĐ±ĐŸŃ‚Ńƒ ĐœĐ°ŃƒĐșĐŸĐČĐŸĐłĐŸ ĐŸĐ±Đ»Đ°ĐŽĐœĐ°ĐœĐœŃ ĐŽĐ»Ń ĐČĐžĐșĐŸĐœĐ°ĐœĐœŃ ĐŽĐŸŃĐ»Ń–ĐŽĐœĐžŃ†ŃŒĐșох ĐżŃ€ĐŸĐłŃ€Đ°ĐŒ НАН ĐŁĐșŃ€Đ°Ń—ĐœĐž. ĐžĐżĐžŃĐ°ĐœĐ° ŃĐžŃŃ‚Đ”ĐŒĐ° ДлДĐșŃ‚Ń€ĐŸĐ¶ĐžĐČĐ»Đ”ĐœĐœŃ ĐșĐŸĐŒĐżĐ»Đ”Đșсу та Ń€Đ”Đ¶ĐžĐŒĐž Đ”ĐœĐ”Ń€ĐłĐŸŃĐżĐŸĐ¶ĐžĐČĐ°ĐœĐœŃ ĐșĐŸĐŒĐżĐ»Đ”Đșсу. ĐžĐżĐžŃĐ°ĐœĐŸ ĐżŃ€ĐžŃŃ‚Ń€ĐŸŃ— Ń€Đ°ĐŽĐ°Ń€ĐœĐŸŃ— ŃĐžŃŃ‚Đ”ĐŒĐž, Đ° таĐșĐŸĐ¶ ĐœĐ°ĐčĐ±Ń–Đ»ŃŒŃˆ ĐżĐŸŃ‚ŃƒĐ¶ĐœŃ– ŃĐżĐŸĐ¶ĐžĐČачі ДлДĐșŃ‚Ń€ĐŸĐ”ĐœĐ”Ń€ĐłŃ–Ń—, яĐșі ŃĐżĐŸĐ¶ĐžĐČають ДлДĐșŃ‚Ń€ĐŸĐ”ĐœĐ”Ń€ĐłŃ–ŃŽ ĐœĐ° Đ”ĐșŃĐżĐ”Ń€ĐžĐŒĐ”ĐœŃ‚Đ°Đ»ŃŒĐœŃ– і ĐłĐŸŃĐżĐŸĐŽĐ°Ń€ŃŃŒĐșі ĐżĐŸŃ‚Ń€Đ”Đ±Đž. ĐŸŃ€ĐŸĐ°ĐœĐ°Đ»Ń–Đ·ĐŸĐČĐ°ĐœĐŸ Đ”ĐœĐ”Ń€ĐłĐŸŃĐżĐŸĐ¶ĐžĐČĐ°ĐœĐœŃ ĐșĐŸĐŒĐżĐ»Đ”Đșсу ĐœĐ”ĐșĐŸĐłĐ”Ń€Đ”ĐœŃ‚ĐœĐŸĐłĐŸ Ń€ĐŸĐ·ŃŃ–ŃĐœĐœŃ Đ·Đ° 2013 р. ĐžŃ‚Ń€ĐžĐŒĐ°ĐœĐŸ і прДЎстаĐČĐ»Đ”ĐœĐŸ графіĐșĐž ŃĐ”Ń€Đ”ĐŽĐœŃŒĐŸŃ— ŃĐżĐŸĐ¶ĐžĐČĐ°ĐœĐŸŃ— ĐżĐŸŃ‚ŃƒĐ¶ĐœĐŸŃŃ‚Ń– (ŃĐ”Ń€Đ”ĐŽĐœŃŒĐŸĐŽĐŸĐ±ĐŸĐČĐžĐč ĐżĐŸĐșĐ°Đ·ĐœĐžĐș) і ŃĐ”Ń€Đ”ĐŽĐœŃŒĐŸŃ— ŃĐżĐŸĐ¶ĐžĐČĐ°ĐœĐŸŃ— ĐżĐŸŃ‚ŃƒĐ¶ĐœĐŸŃŃ‚Ń– ĐČ Ń€Đ”Đ¶ĐžĐŒŃ– ĐČĐžĐŒŃ–Ń€ŃŽĐČĐ°ĐœŃŒ. ĐžĐżĐžŃĐ°ĐœĐ° ĐŽĐŸŃ†Ń–Đ»ŃŒĐœŃ–ŃŃ‚ŃŒ ĐżŃ€ĐŸĐČĐ”ĐŽĐ”ĐœĐœŃ Ń€ĐŸĐ±Ń–Ń‚ Đ· ĐŸĐżŃ‚ĐžĐŒŃ–Đ·Đ°Ń†Ń–Ń— Đ”ĐœĐ”Ń€ĐłĐŸĐżĐŸŃŃ‚Đ°Ń‡Đ°ĐœĐœŃ ĐœĐ°ŃƒĐșĐŸĐČĐŸ-ĐŽĐŸŃĐ»Ń–ĐŽĐœĐŸĐłĐŸ ĐșĐŸĐŒĐżĐ»Đ”Đșсу Đ†ĐœŃŃ‚ĐžŃ‚ŃƒŃ‚Ńƒ Ń–ĐŸĐœĐŸŃŃ„Đ”Ń€Đž. Đ—Đ°ĐżŃ€ĐŸĐżĐŸĐœĐŸĐČĐ°ĐœĐŸ ĐŒĐŸĐ¶Đ»ĐžĐČі Đ·Đ°Ń…ĐŸĐŽĐž ĐŽĐ»Ń Đ·ĐœĐžĐ¶Đ”ĐœĐœŃ Đ”ĐșĐŸĐœĐŸĐŒŃ–Ń‡ĐœĐŸŃ— ĐČĐ°Ń€Ń‚ĐŸŃŃ‚Ń– ĐżŃ€ĐŸĐČĐ”ĐŽĐ”ĐœĐœŃ Đ”ĐșŃĐżĐ”Ń€ĐžĐŒĐ”ĐœŃ‚Ń–ĐČ Đ· ĐŽĐŸŃĐ»Ń–ĐŽĐ¶Đ”ĐœĐœŃ Ń–ĐŸĐœĐŸŃŃ„Đ”Ń€Đž ĐœĐ°ŃƒĐșĐŸĐČĐŸ-ĐŽĐŸŃĐ»Ń–ĐŽĐœĐŸĐłĐŸ ĐșĐŸĐŒĐżĐ»Đ”Đșсу ĐœĐ”ĐșĐŸĐłĐ”Ń€Đ”ĐœŃ‚ĐœĐŸĐłĐŸ Ń€ĐŸĐ·ŃŃ–ŃĐœĐœŃ. ĐŸŃ€ĐŸĐČĐ”ĐŽĐ”ĐœĐŸ Đ°ĐœĐ°Đ»Ń–Đ· Ń€ĐŸĐ±Ń–Ń‚ ŃŃƒŃ‡Đ°ŃĐœĐžŃ… Đ°ĐČŃ‚ĐŸŃ€Ń–ĐČ Đ· ĐŒĐ”Ń‚ĐŸŃŽ ĐżĐŸĐșĐ°Đ·Đ°Ń‚Đž, Ń‰ĐŸ піЮĐČĐžŃ‰Đ”ĐœĐœŃ ДфДĐșтоĐČĐœĐŸŃŃ‚Ń– Ń„ŃƒĐœĐșŃ†Ń–ĐŸĐœŃƒĐČĐ°ĐœĐœŃ ŃĐžŃŃ‚Đ”ĐŒ ДлДĐșŃ‚Ń€ĐŸĐżĐŸŃŃ‚Đ°Ń‡Đ°ĐœĐœŃ є Đ°ĐșŃ‚ŃƒĐ°Đ»ŃŒĐœĐŸŃŽ ĐżŃ€ĐŸĐ±Đ»Đ”ĐŒĐŸŃŽ ŃŃƒŃ‡Đ°ŃĐœĐžŃ… ĐŽĐŸŃĐ»Ń–ĐŽĐ¶Đ”ĐœŃŒ.This article presents the results of the analysis of the energy consumption modes of the incoherent scattering complex of the Institute of Ionosphere of the National Academy of Sciences and the Ministry of Education and Science of Ukraine to solve the problem of increasing the energy efficiency of a research complex and creating an energy efficient power supply system that will ensure the sustainability of scientific equipment for research programs of the National Academy of Sciences of Ukraine. The system of power supply of the complex and modes of power consumption of the complex are described. The devices of the radar system are described, as well as the most powerful consumers of electricity, which consume electricity for experimental and economic needs. The energy consumption of the incoherent scattering complex in 2013 is analyzed. Graphs of the average power consumption (daily average) and average power consumption in measurement modes were obtained and presented. The feasibility of work to optimize the energy supply of the research complex of the institute of the ionosphere is described. Possible measures are proposed to reduce the economic cost of conducting experiments on the study of the ionosphere of an incoherent scattering research complex. The analysis of the works of modern authors i s carried out in order to show that increasing the efficiency of the power supply systems is an actual problem of modern research

    Measurement of the Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction

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    The Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction is measured in a data sample corresponding to 0.41fb−1fb^{-1} of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2ÎČ\beta measurement from B0→J/ψKS0B^0\to J/\psi K_S^0 The time-integrated branching fraction is measured to be BF(Bs0→J/ψKS0)=(1.83±0.28)×10−5BF(B_s^0\to J/\psi K_S^0)=(1.83\pm0.28)\times10^{-5}. This is the most precise measurement to date

    Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays

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    A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity

    Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays

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    Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.Comment: 15 pages, 10 figures; minor revisions on May 23, 201

    Search for the lepton-flavor-violating decays Bs0→e±Ό∓ and B0→e±Ό∓

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    A search for the lepton-flavor-violating decays Bs0→e±Ό∓ and B0→e±Ό∓ is performed with a data sample, corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions at √s=7  TeV, collected by the LHCb experiment. The observed number of Bs0→e±Ό∓ and B0→e±Ό∓ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(Bs0→e±Ό∓)101  TeV/c2 and MLQ(B0→e±Ό∓)>126  TeV/c2 at 95% C.L., and are a factor of 2 higher than the previous bounds
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