Interplay of magnetism and superconductivity in EuFe2_{2}(As1−x_{1-x}Px_{x})2_{2} single crystals probed by muon spin rotation and 57{}^{57}Fe M\"ossbauer spectroscopy

We present our results of a local probe study on EuFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$ single crystals with $x$=0.13, 0.19 and 0.28 by means of muon spin rotation and ${}^{57}$Fe M\"ossbauer spectroscopy. We focus our discussion on the sample with $x$=0.19 viz. at the optimal substitution level, where bulk superconductivity ($T_{\text{SC}}=28$ K) sets in above static europium order ($T^{\text{Eu}}=20$K) but well below the onset of the iron antiferromagnetic (AFM) transition ($\sim$100 K). We find enhanced spin dynamics in the Fe sublattice closely above $T_{\text{SC}}$ and propose that these are related to enhanced Eu fluctuations due to the evident coupling of both sublattices observed in our experiments.Comment: Contribution to the 13th International Conference on Muon Spin Rotation, Relaxation and Resonance (MuSR2014

EXTERNAL HEAT EXCHANGER IN THE PROCESS OF CONVECTIVE DRINKING OF LUBRICATES

Розглянуто особливості конвективного сушіння деревинних матеріалів (пиломатеріалів, чорнових меблевих заготовок, паркетної фризи тощо). Проведено теоретичні дослідження процесів тепломасоперенесення, внаслідок чого отримано рівняння визначення інтенсивності випаровування вологи з одної поверхні сушіння, коефіцієнта теплообміну за різних режимів руху теплоносія (агента сушіння), а також час сушіння деревини у першому періоді (періоді постійної швидкості сушіння). Розв'язано диференціальні рівняння перенесення тепла для тривіального тіла. Рівняння перенесення тепла доповнено новим членом, який враховує від'ємне джерело теплоти внаслідок об'ємного випаровування частинок рідини (води) у пограничному шарі. Розглянуто визначення конвективного теплообміну для одномірного тіла, а також балансове рівняння теплоти, розв'язане відносно коефіцієнта конвективного теплообміну. Наведено значення співвідношень інтенсивності сушіння до інтенсивності випаровування води з відкритої поверхні для різних режимів сушіння деревини. За результатами аналізу власних досліджень, а також інших учених обґрунтовано роль термодинамічних характеристик деревини під час сушіння пиломатеріалів. Проаналізовано параметри, які впливають на тепло- і масоперенесення під час конвективного сушіння, дано відповідь на питання пришвидшення процесу відведення води з вологого матеріалу, без його гальмування.Рассмотрены особенности конвективной сушки древесных материалов (пиломатериалов, черновых мебельных заготовок, паркетной фризы и т.д.). Проведены теоретические исследования процессов тепломассопереноса, в результате чего получено уравнение для определения интенсивности испарения влаги с одной поверхности сушки, коэффициента теплообмена при различных режимах движения теплоносителя (агента сушки), а также время сушки древесины в первом периоде (периоде постоянной скорости сушки). Решены дифференциальные уравнения переноса тепла для тривиального тела. Уравнение переноса тепла дополнено новым членом, который учитывает отрицательный источник теплоты в результате объемного испарения частиц жидкости (воды) в пограничном слое. Рассмотрены определения конвективного теплообмена для одномерного тела, а также балансовое уравнение теплоты решено относительно коэффициента конвективного теплообмена. Приведены значения соотношений интенсивности сушки к интенсивности испарения воды с открытой поверхности для различных режимов сушки древесины. По результатам анализа собственных исследований, а также других ученых обоснована роль термодинамических характеристик древесины при сушке пиломатериалов. Проведен анализ параметров, влияющих на тепло- и массоперенос при конвективной сушке, дан ответ на вопрос ускорения процесса отвода воды из влажного материала, без его торможения.The features of convective drying of wood materials (lumber, rough furniture preparations, parquet friezes, etc.) are considered in the work. Theoretical studies of heat transfer processes have been carried out, resulting in the equation for determining the intensity of evaporation of moisture from one surface of drying, the heat transfer coefficient under different modes of movement of the heat carrier (drying agent), as well as the drying time of the wood in the first period (the period of constant drying rate). The differential equations of transfer of heat for a trivial body are solved. The heat transfer equation is supplemented by a new member that takes into account the negative heat source as a result of volumetric evaporation of liquid particles (water) in the boundary layer. The definition of convective heat transfer for a one-dimensional body, as well as the balance equation of heat, is solved with respect to the coefficient of convective heat transfer. The values of the ratios of drying intensity to the intensity of evaporation of water from the open surface for different drying conditions are given. Due to the analysis of own research, as well as various scientists, the role of thermodynamic characteristics of wood during drying of sawn timber is substantiated. The analysis of the parameters that influence the heat and mass transfer during convective drying is carried out, the answer to the question of speeding up the process of drawing water from a wet material without its inhibition is given

Survival rate in multifocal atherosclerosis patients who underwent surgical carotid and coronary territories revascularisation

Aim - short-term outcomes of cerebral and coronary artery revascularisation surgeries performed with different methods and different timing have been well studied, but the long-term outcomes have not. The study aim was to determine the long-term survival rates in patients with combined atherosclerotic cerebral and coronary artery lesions who underwent surgical revascularisation of both territories. We evaluated the survival functions of six groups of patients with combined atherosclerotic cerebral and coronary artery lesions who underwent revascularisation using different methods in different sequences and at different time periods of both territories. Survival in each group was determined from postoperative Day 30 by using the Kaplan–Meier method and compared by using the log-rank test. Survival was also compared among the groups in which alternative methods of carotid and coronary territories revascularisation were used. The 5-year survival rates were similar between patients who underwent endovascular revascularisation of both territories (cerebral and coronary arteries stenting) or combined surgery (coronary arteries stenting + carotid endarterectomy). The 5–10-year survival rate was higher in patients who underwent combined surgery than in the other patients (p=0.026). The main causes of death in all groups were cardiac or cerebral events. The 10-year survival rates did not significantly differ between patients who underwent cerebral artery stenting prior to coronary artery bypass grafting and those who underwent simultaneous carotid endarterectomy + coronary artery bypass grafting (p=0.532). The results of this study can be useful for selecting the tactics of surgical cerebral and coronary artery revascularisation, identifying the sequence of respective surgeries and time management. Цель исследования - определение отдаленной выживаемости больных сочетанным атеросклеротическим поражением церебральных и коронарных артерий, перенесших хирургическую реваскуляризацию обоих бассейнов. Исследование функции выживания проведено в шести группах пациентов с сочетанным атеросклеротическим поражением церебральных и коронарных артерий, которым проведена реваскуляризация обоих бассейнов разными методами в различной последовательности и в различные сроки. В каждой группе проводили анализ функции выживаемости, начиная с 30 дня послеоперационного периода, используя оценку Каплана–Мейера. Сравнение функций выживаемости в разных группах проводили по логранговому критерию (logrank test) Сравнение функций выживаемости проводилось в группах пациентов, которым применены альтернативные методики реваскуляризации каротидного и коронарного бассейнов. На протяжении первых 5 лет после проведения реваскуляризации каротидного и коронарного бассейнов функция выживаемости практически не отличалась у пациентов, которым проведены эндоваскулярные операции для реваскуляризации обоих бассейнов (стентирование церебральных и коронарных артерий) и гибридные операции (стентирование коронарных артерий+каротидная эндартерэктомия). В период 5-10 лет после оперативного вмешательства лучше выживали пациенты после гибридных операций (р=0,026). Основными причинами смерти пациентов явились кардиальные и церебральные события, незначительная часть пациентов умирала от других причин. Выживаемость пациентов на протяжении 10 лет после операции практически не отличалась при проведении стентирования церебральных артерий перед аорто-коронарным шунтированием и при симультантной операции каротидная эндартериэктомия+аортокоронарное шунтирование (р=0,532)

Distant field BHB stars and the mass of the Galaxy II: Photometry and spectroscopy of UKST candidates 16<B<19.5, 11<R<52 kpc

This is the second in a series of papers presenting a new calculation of the mass of the Galaxy based on radial velocities and distances for a sample of faint 16 < B < 21.3 field blue horizontal-branch (BHB) stars. We present accurate BV CCD photometry and spectra for 142 candidate A-type stars selected from ub_jr photometry of UK Schmidt telescope plates in six high-Galactic-latitude fields. Classification of these candidates produces a sample of 60 BHB stars at distances of 11-52 kpc from the Sun (mean 28 kpc), with heliocentric line-of-sight velocities accurate to 15 km/s, and distance errors < 10%. We provide a summary table listing coordinates and velocities of these stars. The measured dispersion of the radial component of the Galactocentric velocity for this sample is 108+-10 km/s, in agreement with a recent study of the distant halo by Sirko and coworkers. Measurements of the Ca II K line indicate that nearly all the stars are metal-poor with a mean [Fe/H] = -1.8 with dispersion 0.5. Subsequent papers will describe a second survey of BHBs to heliocentric distances 70 < R < 125 kpc and present a new estimate of the mass of the Galaxy.Comment: 16 pages, 15 figures. Accepted for publication in MNRA

Prognostic factors of intracranial purulent-septic complications of combat-related gunshot penetrating skull and brain wounds.

Purpose – to ana­lyze the structure of intracranial purulent-septic complications (IPSC), determine the factors influencing development of purulent-septic complications in patients with combat-related gunshot penetrating skull and brain wounds (CRPSBW), determine the effect of intracranial PSC on patients’ outcomes. A prospective analysis of results of exa­mination and treatment of 121 patients was performed. All patients had gunshot penetrating skull and brain wounds sustained in combat conditions during a local armed conflict in the Eastern Ukraine. Evaluation of treatment outcome included analysis of mortality in 1 month (survived/died) and dichotomous Glasgow Outcome Scale (GOS) score in 12 months (favorable/unfavorable outcome). 121 wounded men aged 18 to 56 (average, 34.1±9.1) were included in the study. Intracranial purulent-septic complications (IPSC) were diagnosed in 14 (11.6%) gunshot CRPSBW patients. The following prognostic factors had statistically significantly correlation with the risk of intracranial purulent-septic complications development: wound liquorrhea on admission (p = 0.043), intraventricular hemorrhage (p = 0.007), bone fragments left in the wound (p = 0.0152), and  duration of inflow-outflow wound drainage for more than 3 days (p= 0.0123). Intracranial PSC patients had mortality rate of 50%, and only 14.3% of those patients had a favorable outcome according to GOS score in one year. Presence of intracranial PSC had statistically significant association with mortality rate (p=0.0091) and GOS score in one year (p=0.0001)

Detection of the ellipsoidal and the relativistic beaming effects in the CoRoT-3 lightcurve

CoRoT-3b is a 22 Jupiter-mass massive-planet/brown-dwarf object, orbiting an F3-star with a period of 4.3 days. We analyzed the out-of-transit CoRoT-3 red-channel lightcurve obtained by the CoRoT mission and detected the ellipsoidal modulation, with half the orbital period and amplitude of 59+/-9 ppm (parts per million) and the relativistic beaming effect, with the orbital period and an amplitude of 27+/-9 ppm. Phases and amplitudes of both modulations were consistent with our theoretical approximation.Comment: Published in Astronomy & Astrophysics. 5 pages, 2 figure

Experimental and numerical investigation of the reflection coefficient and the distributions of Wigner's reaction matrix for irregular graphs with absorption

We present the results of experimental and numerical study of the distribution of the reflection coefficient P(R) and the distributions of the imaginary P(v) and the real P(u) parts of the Wigner's reaction K matrix for irregular fully connected hexagon networks (graphs) in the presence of strong absorption. In the experiment we used microwave networks, which were built of coaxial cables and attenuators connected by joints. In the numerical calculations experimental networks were described by quantum fully connected hexagon graphs. The presence of absorption introduced by attenuators was modelled by optical potentials. The distribution of the reflection coefficient P(R) and the distributions of the reaction K matrix were obtained from the measurements and numerical calculations of the scattering matrix S of the networks and graphs, respectively. We show that the experimental and numerical results are in good agreement with the exact analytic ones obtained within the framework of random matrix theory (RMT).Comment: 15 pages, 8 figure

Correlations due to localization in quantum eigenfunctions of disordered microwave cavities

Non-universal correlations due to localization are observed in statistical properties of experimental eigenfunctions of quantum chaotic and disordered microwave cavities. Varying energy {E} and mean free path {l} enable us to experimentally tune from localized to delocalized states. Large level-to-level Inverse Participation Ratio (IPR I_{2}) fluctuations are observed for the disordered billiards, whose distribution is strongly asymmetric about . The density auto-correlations of eigenfunctions are shown to decay exponentially and the decay lengths are experimentally determined. All the results are quantitatively consistent with calculations based upon nonlinear sigma-models.Comment: 4 pages, LaTex, 5 .jpg figures. This paper with 5 embedded postscript figures available (PS,PDF) at http://sagar.physics.neu.edu/preprints

Explicitly solvable cases of one-dimensional quantum chaos

We identify a set of quantum graphs with unique and precisely defined spectral properties called {\it regular quantum graphs}. Although chaotic in their classical limit with positive topological entropy, regular quantum graphs are explicitly solvable. The proof is constructive: we present exact periodic orbit expansions for individual energy levels, thus obtaining an analytical solution for the spectrum of regular quantum graphs that is complete, explicit and exact