Acceleration of the precession frequency for optically-oriented electron spins in ferromagnetic/semiconductor hybrids

Time-resolved Kerr rotation measurements were performed in InGaAs/GaAs quantum wells nearby a doped Mn delta layer. Our magneto-optical results show a typical time evolution of the optically-oriented electron spin in the quantum well. Surprisingly, this is strongly affected by the Mn spins, resulting in an increase of the spin precession frequency in time. This increase is attributed to the variation in the effective magnetic field induced by the dynamical relaxation of the Mn spins. Two processes are observed during electron spin precession: a quasi-instantaneous alignment of the Mn spins with photo-excited holes, followed by a slow alignment of Mn spins with the external transverse magnetic field. The first process leads to an equilibrium state imprinted in the initial precession frequency, which depends on pump power, while the second process promotes a linear frequency increase, with acceleration depending on temperature and external magnetic field. This observation yields new information about exchange process dynamics and on the possibility of constructing spin memories, which can rapidly respond to light while retaining information for a longer period.Comment: 7 pages, 5 figure

Predictive scales and ECG indicators in the acute stroke period

The features of the ECG in patients with different values of the SAPS and APACHE II scales in the acute period of stroke were investigated. Despite the fact that the APACHE II and SAPS scales do not include ECG parameters, a number of ECG parameters significantly differ in patients with acute stroke at different values according to these scales. The prognosis aggravation according to the studied scales was not always accompanied by the same type of ECG parameters changes. Survived patients with high APACHE II scores were characterized by high dysmorphic values of ECG amplitude parameters. Died patients with high risks on both scales showed an increase in dysmorphism in many ECG parameters. The scientific novelty of the study is in the detection of ECG features at different values of the SAPS and APACHE II scales in the acute period of stroke.Изучены особенности ЭКГ у пациентов при разных значениях шкал SAPS и APACHE II в остром периоде инсульта. Несмотря на то, что шкалы APACHE II и SAPS не включают в себя параметры ЭКГ, у пациентов с острым инсультом при различных значениях по данным шкалам ряд показателей ЭКГ достоверно отличались. Ухудшение прогноза по изученным шкалам не всегда сопровождалось однотипными изменениями показателей ЭКГ. Выжившие пациенты с высокими значениями по шкале APACHE II характеризовались большими показателями дизморфности амплитудных значений ЭКГ. Умершие пациенты с высокими рисками по обеим шкалам демонстрировали увеличение дизморфности по многим показателям ЭКГ. Научная новизна исследования заключается в обнаружении особенностей ЭКГ при различных рисках осложнений по шкалам SAPS и APACHE II в остром периоде инсульта

NEW APPROACH TO ADDITIONAL LEFT-TURN SECTIONS OF THE TRAFFIC SIGNAL REGULATION

Introduction. The paper describes methods of using the additional left-turn phase of regulation. The authors view the main foreign and domestic methods used in the specialization of the left turn in a separate phase of regulation. To propose a new approach to the specialization of the left-turn direction in a separate phase of regulation the authors investigate one of the most loaded intersections in Voronezh and determine the main characteristics of the traffic flow. Therefore, the authors suggest new parameters in choosing of the necessary method of traffic organization at controlled intersections.Methods and materials. The paper analyses the main methods, which were conditionally related to two approaches: the accident rate of the site and the characteristics of the traffic flow (speed and intensity of the left-turn flow). The authors explained that the new approach, which took into account such parameters as speed, vehicle delays and queue length, allowed effectively controlling the intersection due to the optimal choice of the necessary traffic organization method and due to the result of changes in the parameters by combining the intensity of the left-turn flow and forward flow.Results. The authors developed the approach to the additional left-turn section introduction at the controlled intersection based on a comparison of the left-turn intensity and forward flow and on the analysis of changes in the main characteristics of the traffic flow (speed, vehicle delays and queue length).Discussion and conclusions. The authors concluded that it is necessary to use the proposed approach at the stage of modeling, design and reorganization of the regulated area on the basis of changes in the main characteristics of the traffic flow