Influence of the photon - neutrino processes on magnetar cooling

The photon-neutrino processes $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$, $\gamma \to \nu \bar \nu$ and $\gamma \gamma \to \nu \bar \nu$ are investigated in the presence of a strongly magnetized and dense electron-positron plasma. The amplitudes of the reactions $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$ and $\gamma \gamma \to \nu \bar \nu$ are obtained. In the case of a cold degenerate plasma contributions of the considering processes to neutrino emissivity are calculated. It is shown that contribution of the process $\gamma \gamma \to \nu \bar \nu$ to neutrino emissivity is supressed in comparision with the contributions of the processes $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$ and $\gamma \to \nu \bar \nu$. The constraint on the magnetic field strength in the magnetar outer crust is obtained.Comment: 8 pages, LaTeX, 2 PS figures, based on the talk presented by D.A. Rumyantsev at the XV International Seminar Quarks'2008, Sergiev Posad, Moscow Region, May 23-29, 2008, to appear in the Proceeding

Charged Rotating Black Holes in Equilibrium

Axially symmetric, stationary solutions of the Einstein-Maxwell equations with disconnected event horizon are studied by developing a method of explicit integration of the corresponding boundary-value problem. This problem is reduced to non-leaner system of algebraic equations which gives relations between the masses, the angular momenta, the angular velocities, the charges, the distance parameters, the values of the electromagnetic field potential at the horizon and at the symmetry axis. A found solution of this system for the case of two charged non-rotating black holes shows that in general the total mass depends on the distance between black holes. Two-Killing reduction procedure of the Einstein-Maxwell equations is also discussed.Comment: LaTeX 2.09, no figures, 15 pages, v2, references added, introduction section slightly modified; v3, grammar errors correcte

Pedagogical conditions of interethnic relations correction in educational environment

© 2016 Shibankova et al.The research urgency is conditioned by the strengthening of the role of educational institutions in the process of interaction between representatives of different cultures and religions, by the creation of favorable socio-psychological climate. Within the study of the educational environment, the authors identify its properties, conditioning the warning of students to be involved in radical and extremist activities. The authors conducted a sociological study of the level of students’ ethnic tolerance (Kazan, Russia). The results of the study identify the need for correction of inter-ethnic relations that reduce their tension. The authors developed four levels of pedagogical conditions for correction of interethnic relations in educational environment (conceptual, contextual, technological, cadre). The paper is intended for researchers, teachers, psychologists, sociologists, dealing with the problems of preventive measures against ideology of extremism and for security in an educational environment

Сравнительная оценка заживления раны при использовании локального лоскута и полнослойного кожного трансплантата в реконструктивно-восстановительной хирургии головы и шеи

Objective: to present a comparative analysis of wound healing process and to evaluate the clinical effectiveness of using a local flap and a full-thickness skin graft in reconstructive surgery of head and neck skin tumors.Materials and methods. There were analyzed the results of 524 patients’ treatments in the Yaroslavl Regional Clinical Oncological Hospital over the period from 2000 to 2013. For 478 patients skin tumors excisions were performed by the reconstruction with a local flap, and for 46 patients – with a full-thickness skin graft. While making an assessment of wound healing it was considered the dynamics of clinical symptomatology, clinical laboratory measurements, the results of local thermometry, of bacteriological and morphological studies, as well as the results of wound-tensiometry studies. As a comparison of averages, they used Student’s t-test, Mann–Whitney test, χ2 test and Fisher’s exact test with statistically significant results at p < 0,05.Results. Comprehensive assessment of wound healing after skin tumors excisions of the head and neck with the elimination of the formed defect by using a local flap or a full-thickness skin graft showed that there was a vibrant local inflammatory reaction in both groups of patients up to 5–7 days after the operation. It was determined not only clinically, but also by objective criteria which characterized the wound healing process. Moreover, the hallmark of plastic reconstruction by skin graft was moderate intensity of local inflammation with the background of perceivable trophic abnormalities. Ultimately, the defined characteristics of wound healing process were as-sociated with a high incidence of complicated wound healing, up to 52.2 % using the skin graft and 33.1 % – the local flap. There were prevailed graft trophism problems in the complications structure in the form of partial or complete necrosis, which were particularly characterized for wound closing by free graft. From oncology position indicated wound risks were accompanied sufficiently high 5-year survival rate (81.8 and 93.9 %, respectively). Generally, choosing reconstructive surgery tactics to close the skin defect of the head and neck and considering a smaller percentage of complications it is preferred to use a local flap, in comparison with a free skin graft.Цель исследования – представить сравнительную характеристику течения раневого процесса и оценить клиническую эффективность использования локального лоскута и полнослойного кожного трансплантата в реконструктивной хирургии новообразований кожи головы и шеи.Материалы и методы. Проанализированы результаты лечения 524 пациентов в Ярославской областной клинической онкологической больнице в период с 2000 по 2013 г., среди которых 478 больным было выполнено иссечение новообразования кожи с реконструкцией локальным лоскутом, 46 – полнослойным кожным трансплантатом. При оценке заживления раны учитывали динамику клинической симптоматики, клинико-лабораторных показателей, данные локальной термометрии, бактериологического и морфологического исследований, а также ранотензиометрии. Для сравнения средних величин использовали t-критерий Стьюдента, критерий Манна–Уитни, критерий χ2 и точный критерий Фишера со статистической значимостью результатов при p < 0,05.Результаты. Комплексная оценка заживления раны после иссечения новообразования кожи головы и шеи с ликвидацией образовавшегося дефекта с помощью локального лоскута или полнослойного кожного трансплантата показала, что в обеих группах больных до 5–7 сут после операции наблюдалась выраженная местная воспалительная реакция. Она определялась не только клинически, но и посредством объективных критериев, характеризующих течение раневого процесса. При этом отличительной чертой пластики полнослойной кожей была умеренная выраженность локального воспаления на фоне ощутимых трофических нарушений. Выявленные особенности течения раневого процесса были сопряжены с высокой частотой встречаемости осложненного заживления раны, достигающей 52,2 % при закрытии раны кожным трансплантатом и 33,1 % – локальным лоскутом. В структуре осложнений превалировали проблемы, связанные с трофикой лоскута, в виде частичного или полного его некроза, которые были особенно характерны для закрытия раны свободной кожей. С онкологических позиций указанные риски со стороны раны сопровождались достаточно высокой 5-летней выживаемостью (81,8 и 93,9 % соответственно). В целом при выборе тактики выполнения реконструктивной операции для закрытия дефекта кожи головы и шеи с учетом меньшего процента осложнений предпочтительно использование локального лоскута по сравнению с пластикой свободным кожным трансплантатом

ЗАЖИВЛЕНИЕ РАНЫ И КЛИНИЧЕСКАЯ РЕЗУЛЬТАТИВНОСТЬ ПЕРВИЧНОГО ШВА В ХИРУРГИИ НОВООБРАЗОВАНИЙ МЯГКИХ ТКАНЕЙ ГОЛОВЫ И ШЕИ

Analyzed the results of treatment of 584 patients operated on for soft tissue tumors of the head and neck with the elimination of the defect formed by directly comparing the edges of wounds by primary suture. Taking into account the level of the wound by M.I. Kuzin et al. (1977), the dynamics of clinical and laboratory results, morphological, biological research, local thermometry and vulnotenziometry. Statistical significance was estimated using the Student's t-test, Mann–Whitney U-test, and criteria χ2 and Fisher with certainty changes in p < 0.05. Found that in the majority of patients kept the wound heals biologically programmed tissue reactions. At the same time, high bacterial contamination of integumentary tissues in the area of operations, especially against the background of the malignant tumor was a risk factor for the development of wound complications in 18 % of patients. The observed the oncological impact was characterized by the five-year survival at 90.6 ± 1.9 %. The 4.5 ± 1.9 % of patients had a direct link to death from malignant tumor.Анализированы результаты лечения 584 пациентов, оперированных по поводу опухоли мягких тканей головы и шеи с ликвидацией образовавшегося дефекта путем прямого сопоставления краев раны наложением первичного шва. С учетом стадийности раневого процесса по М.И. Кузину с соавт. (1977) представлена динамика результатов клинико-лабораторного, морфологического, бактериологического исследований, локальной термометрии и ранотензиометрии. Статистическая значимость оценивалась посредством t-критерия Стьюдента, критериев Манна–Уитни, χ2 и Фишера с достоверностью изменений при p < 0,05. Установлено, что у большинства больных заживление раны укладывалось в рамки биологически запрограммированных ткане- вых реакций. В то же время высокая бактериальная контаминация покровных тканей в зоне операции, особенно на фоне злокачественной опухоли, являлась фактором риска для развития раневых осложнений у 18 % пациентов. Наблюдаемая при этом онкологическая результативность характеризовалась 5-летней выживаемостью на уровне 90,6 ± 1,9 %. У 4,5 ± 1,9 % больных летальный исход имел прямую связь со злокачественной опухолью.

Fine-tuning of Silica Coating Procedure for Preparation of Biocompatible and Bright Pbs/Sio2 Qds

Near-infrared semiconductor PbS quantum dots (QDs) with emission in biological transparency window are promising material for in vivo biolabelling and deep-tissue imaging of biological specimen. Among various approaches that render initially hydrophobic and toxic QDs biocompatible, the growth of a silica shell on the QD surface represents an efficient method to minimize QD toxicity. Nevertheless, it is important to preserve QDs emission properties after the silica coating procedure. Here we report on the optimal parameters of this procedure which allow to obtain a stable silica shell and maintain the optical properties of initial PbS QDs. Furthermore, we show that PbS QDs with the optimal SiO2 shell retain their luminescence quantum yield even after condensation into a solid film. Thus, our procedure can become a basis in development of bright, receptor-targeted NIR fluorescent probes for in vivo tumor imaging. Keywords: quantum dot, SiO2 shell, bioimagin

Electric field of a pointlike charge in a strong magnetic field and ground state of a hydrogenlike atom

In an external constant magnetic field, so strong that the electron Larmour length is much shorter than its Compton length, we consider the modification of the Coulomb potential of a point charge owing to the vacuum polarization. We establish a short-range component of the static interaction in the Larmour scale, expressed as a Yukawa-like law, and reveal the corresponding "photon mass" parameter. The electrostatic force regains its long-range character in the Compton scale: the tail of the potential follows an anisotropic Coulomb law, decreasing away from the charge slower along the magnetic field and faster across. In the infinite-magnetic-field limit the potential is confined to an infinitely thin string passing though the charge parallel to the external field. This is the first evidence for dimensional reduction in the photon sector of quantum electrodynamics. The one-dimensional form of the potential on the string is derived that includes a delta-function centered in the charge. The nonrelativistic ground-state energy of a hydrogenlike atom is found with its use and shown not to be infinite in the infinite-field limit, contrary to what was commonly accepted before, when the vacuum polarization had been ignored. These results may be useful for studying properties of matter at the surface of extremely magnetized neutron stars.Comment: 45 pages, 6 figures, accepted to Phys. Rev.

Formation of "Lightnings" in a Neutron Star Magnetosphere and the Nature of RRATs

The connection between the radio emission from "lightnings" produced by the absorption of high-energy photons from the cosmic gamma-ray background in a neutron star magnetosphere and radio bursts from rotating radio transients (RRATs) is investigated. The lightning length reaches 1000 km; the lightning radius is 100 m and is comparable to the polar cap radius. If a closed magnetosphere is filled with a dense plasma, then lightnings are efficiently formed only in the region of open magnetic field lines. For the radio emission from a separate lightning to be observed, the polar cap of the neutron star must be directed toward the observer and, at the same time, the lightning must be formed. The maximum burst rate is related to the time of the plasma outflow from the polar cap region. The typical interval between two consecutive bursts is ~100 s. The width of a single radio burst can be determined both by the width of the emission cone formed by the lightning emitting regions at some height above the neutron star surface and by a finite lightning lifetime. The width of the phase distribution for radio bursts from RRATs, along with the integrated pulse width, is determined by the width of the bundle of open magnetic field lines at the formation height of the radio emission. The results obtained are consistent with the currently available data and are indicative of a close connection between RRATs, intermittent pulsars, and extreme nullers.Comment: 24 pages, no figures, references update

STUDY OF THE ORGANIC LUMINOPHORES PHOTOSTABILITY IN POROUS SILICON MICROCAVITIES

The work is devoted to the study of the photostability of the pyrimidine derivatives and conjugated organic polymers of the PPV class embedded in a porous silicon microcavity