58 research outputs found

    Transformations in the grain boundary ensemble of M1 copper subjected to equal-channel angular pressing during recrystallization annealing

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    The grain structure of M1 copper subjected to equal-channel angular pressing (ECAP) and subsequent annealing at 593K for 1 h is studied by means of transmission electron microscopy and scanning electron microscopy with the diffraction of backscattered electron

    First Measurement of Chiral Dynamics in \pi^- \gamma -> \pi^- \pi^- \pi^+

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    The COMPASS collaboration at CERN has investigated the \pi^- \gamma -> \pi^- \pi^- \pi^+ reaction at center-of-momentum energy below five pion masses, sqrt(s) < 5 m(\pi), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t' < 0.001 (GeV/c)^2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3\pi-invariant mass m(3\pi) = sqrt(s) were extracted. The absolute cross section was determined in seven bins of s\sqrt{s} with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.Comment: 10 pages, 5 figure

    Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS

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    The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda and anti-lambda produced in the current fragmentation region exhibit different behaviours as a function of x and xF . The measured x and xF dependences of D^lambda_LL are compatible with zero, while D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the frame of recent model calculations.Comment: 13 pages, 7 figure

    Azimuthal asymmetries of charged hadrons produced by high-energy muons scattered off longitudinally polarised deuterons

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    Azimuthal asymmetries in semi-inclusive production of positive (h^+) and negative hadrons (h^-) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle phi of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all phi-modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h^+ and h^- within the statistical errors. The dependencies of the phi-modulated terms versus the Bjorken momentum fraction x, the hadron fractional momentum z, and the hadron transverse momentum p_h^T were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudinal double-spin hadron asymmetries, measured in semi-inclusive deep-inelastic scattering. The x dependence of the sin phi-modulation term is less pronounced than that in the corresponding HERMES data. All other dependencies of the phi-modulation amplitudes are consistent with zero within the statistical errors.Comment: 12 pages, 11 Figures; revision 1 signs in Eq 5 corrected, polishe

    Информационная ценность однократно измеренного при поступлении в ОРИТ проадреномедуллина в крови у пациентов с септическим шоком

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    The objective: to assess the information value of proadrenomedullin (PAM), once measured upon admission to ICU in predicting mortality and differential diagnosis of septic and hypovolemic shock.Subjects and Methods. A prospective cohort retrospective study was carried out. 134 patients in a state of shock were included in the study. Of these, 125 patients had septic shock; 9 ‒ hypovolemic one. The diagnosis of septic shock was established according to the Sepsis-3 criteria. To compare hypovolemic and septic shock, blood levels of proadrenomedullin (PAM), procalcitonin (PCT) and lactate were tested in 9 patients with obvious hypovolemic shock. Samples (venous blood) were collected within 24 hours from the moment the vasopressors began to be used in ICU or by the ambulance team (EMS).Results. The ROC analysis showed comparable predictive value with APACHE II, SOFA and lactate scales in patients with septic shock with cut-off &gt; 4.23 nmol/L. The range of PAM values in patients with septic shock was Me 4.56 (2.9‒6.7) in patients with hypovolemic shock – Me 0.6 (0.1‒1.4).Conclusion. Proadrenomedullin can be used for differential diagnosis of septic shock and hypovolemic shock. Blood levels greater than 2.9 nmol/L are of absolute value for the diagnosis of septic shock. Procalcitonin is inferior to PAM within the range of 1.0–6.45 ng/ml. PAM unlike SCT is a statistically significant predictor of global outcome in septic shock along with lactate and scales. But such scales as SOFA and ARACНE-II are more laborious in comparison with testing proadrenomedullin blood level.Цель: оценка информационной ценности однократно измеренного при поступлении в отделение реанимации и интенсивной терапии (ОРИТ) проадреномедуллина (ПАМ) в прогнозировании летального исхода и дифференциальной диагностики септического и гиповолемического шока.Материал и методы. В когортное проспективно-ретроспективное исследование включено 134 пациента в состоянии шока: 125 ‒ септического и 9 – гиповолемического. Гиповолемический и септический шок сравнивали по содержанию в крови ПАМ, прокальцитонина (ПКТ) и лактата. Взятие биоматериала (венозной крови) производили в течение 24 ч от момента начала применения вазопрессоров в ОРИТ или бригадой скорой медицинской помощи.Результаты. ROC-анализ показал прогностическую ценность ПАМ, сопоставимую со шкалами APACHE-II, SOFA и лактатом у больных с септическим шоком при cut off &gt; 4,23 нмоль/л. Разброс значений ПАМ составил: у больных с септическим шоком ‒ Me 4,56 (2,9–6,7) нмоль/л, у больных с гиповолемическим шоком ‒ Me 0,6 (0,1–1,4) нмоль/л.Заключение. ПАМ может быть использован для дифференциальной диагностики септического с гиповолемическим шоком. Абсолютное значение в отношении диагностики септического шока имеет уровень в крови, превышающий 2,9 нмоль/л. ПКТ уступает ПАМ в разграничении септического шока с гиповолемическим в диапазоне значений – 1,0–6,45 нг/мл. ПАМ, в отличие от ПКТ, обладает статистически значимой предикацией глобального исхода при септическом шоке наряду с лактатом и шкалами. Но использование таких шкал, как SOFA и АРАСНЕ-II, более трудоемко по сравнению с определением ПАМ в крови

    Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets

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    This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible modifications arising during this process.Comment: 10 pages, 14MB, accepted by FAIR STI in May 2009, editors: Inti Lehmann (chair), Andrea Bersani, Yuri Lobanov, Jost Luehning, Jerzy Smyrski, Technical Coordiantor: Lars Schmitt, Bernd Lewandowski (deputy), Spokespersons: Ulrich Wiedner, Paola Gianotti (deputy

    Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering

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    First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities.Comment: 13 pages, 4 figures, updated to the published versio

    Quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering

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    Double-spin asymmetries for production of charged pions and kaons in semi-inclusive deep-inelastic muon scattering have been measured by the COMPASS experiment at CERN. The data, obtained by scattering a 160 GeV muon beam off a longitudinally polarised NH_3 target, cover a range of the Bjorken variable x between 0.004 and 0.7. A leading order evaluation of the helicity distributions for the three lightest quarks and antiquark flavours derived from these asymmetries and from our previous deuteron data is presented. The resulting values of the sea quark distributions are small and do not show any sizable dependence on x in the range of the measurements. No significant difference is observed between the strange and antistrange helicity distributions, both compatible with zero. The integrated value of the flavour asymmetry of the helicity distribution of the light-quark sea, \Delta u-bar - \Delta d-bar, is found to be slightly positive, about 1.5 standard deviations away from zero.Comment: 13 pages, 5 figure
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