Thermal radiation and near-field energy density of thin metallic films

We study the properties of thermal radiation emitted by a thin dielectric slab, employing the framework of macroscopic fluctuational electrodynamics. Particular emphasis is given to the analytical construction of the required dyadic Green's functions. Based on these, general expressions are derived for both the system's Poynting vector, describing the intensity of propagating radiation, and its energy density, containing contributions from non-propagating modes which dominate the near-field regime. An extensive discussion is then given for thin metal films. It is shown that the radiative intensity is maximized for a certain film thickness, due to Fabry-Perot-like multiple reflections inside the film. The dependence of the near-field energy density on the distance from the film's surface is governed by an interplay of several length scales, and characterized by different exponents in different regimes. In particular, this energy density remains finite even for arbitrarily thin films. This unexpected feature is associated with the film's low-frequency surface plasmon polariton. Our results also serve as reference for current near-field experiments which search for deviations from the macroscopic approach

Shape-dependence of near-field heat transfer between a spheroidal nanoparticle and a flat surface

We study the radiative heat transfer between a spheroidal metallic nanoparticle and a planar metallic sample for near- and far-field distances. In particular, we investigate the shape dependence of the heat transfer in the near-field regime. In comparison with spherical particles, the heat transfer typically varies by factors between 1/2 and 2 when the particle is deformed such that its volume is kept constant. These estimates help to quantify the deviation of the actual heat transfer recorded by a near-field scanning thermal microscope from the value provided by a dipole model which assumes a perfectly spherical sensor

Magnetic phase diagram and transport properties of FeGe_2

We have used resistivity measurements to study the magnetic phase diagram of the itinerant antiferromagnet FeGe_2 in the temperature range from 0.3->300 K in magnetic fields up to 16 T. In contrast to theoretical predictions, the incommensurate spin density wave phase is found to be stable at least up to 16 T, with an estimated critical field \mu _0H_c of ~ 30 T. We have also studied the low temperature magnetoresistance in the [100], [110], and [001] directions. The transverse magnetoresistance is well described by a power law for magnetic fields above 1 T with no saturation observed at high fields. We discuss our results in terms of the magnetic structure and the calculated electronic bandstructure of FeGe_2. We have also observed, for the first time in this compound, Shubnikov-de Haas oscillations in the transverse magnetoresistance with a frequency of 190 +- 10 T for a magnetic field along [001].Comment: 13 pages, RevTeX, 7 postscript figures, to appear in Journal of Physics: Condensed Matte

Dissipative Van der Waals interaction between a small particle and a metal surface

We use a general theory of the fluctuating electromagnetic field to calculate the friction force acting on a small neutral particle, e.g., a physisorbed molecule, or a nanoscale object with arbitrary dispersive and absorptive dielectric properties, moving near a metal surface. We consider the dependence of the electromagnetic friction on the temperature $T$, the separation $d$, and discuss the role of screening, non-local and retardation effects. We find that for high resistivity materials, the dissipative van der Waals interaction can be an important mechanism of vibrational energy relaxation of physisorbed molecules, and friction for microscopic solids. Several controversial topics related to electromagnetic dissipative shear stress is considered. The problem of local heating of the surface by an STM tip is also briefly commented on.Comment: 11 pages, No figure

ВНУТРИПОЛОСТНАЯ ТЕРАПИЯ ОЗОНИРОВАННЫМ АНТИСЕПТИЧЕСКИМ РАСТВОРОМ В КОМПЛЕКСНОМ ЛЕЧЕНИИ ПАЦИЕНТОВ С ИНФИЦИРОВАННЫМИ ПОЛОСТНЫМИ ОБРАЗОВАНИЯМИ ПЕЧЕНИ

Application   in  the   treatment of  patients  with  infected  cavitary  formations  liver intracavitary therapy ozonated antiseptic allowed  significantly  speed  up the  recovery  of liver function, reduce  the  time of hospital  treatment, to accelerate the  elimination  of the abscess  cavity.Применение в лечении у пациентов с инфицированными полостными образованиями печени внутриполостной терапии озонированным антисептическим раствором позволило достоверно ускорить  восстановление функции печени,  уменьшить сроки стационарного лечения, ускорить ликвидацию полости абсцесса

ЭТИОЛОГИЧЕСКИЕ ФАКТОРЫ РАЗВИТИЯ АБСЦЕССОВ ПЕЧЕНИ

Liver abscesses of various origins are the group of severe purulent diseases of the liver and it is considered one of the difficult problems of the hepatobiliary system. The article presents the current data on the causes and microbiological composition of pathogens liver abscesses.Абсцессы печени различного генеза являются группой тяжелых гнойных заболеваний печени и считаются одной из сложных проблем гепатобилиарной системы. В статье приведены современные данные о причинах развития и микробиологическом составе возбудителей абсцессов печени

Electromagnetic field correlations near a surface with a nonlocal optical response

The coherence length of the thermal electromagnetic field near a planar surface has a minimum value related to the nonlocal dielectric response of the material. We perform two model calculations of the electric energy density and the field's degree of spatial coherence. Above a polar crystal, the lattice constant gives the minimum coherence length. It also gives the upper limit to the near field energy density, cutting off its $1/z^3$ divergence. Near an electron plasma described by the semiclassical Lindhard dielectric function, the corresponding length scale is fixed by plasma screening to the Thomas-Fermi length. The electron mean free path, however, sets a larger scale where significant deviations from the local description are visible.Comment: 15 pages, 7 figure files (.eps), \documentclass[global]{svjour}, accepted in special issue "Optics on the Nanoscale" (Applied Physics B, eds. V. Shalaev and F. Tr\"ager

The use of role-play as a model of teaching palliative care to interns in general medical practice

Contemporary medical higher education, especially the postgraduate training of physicians, requires a creative teaching approach to train a competent health care professional. The use of interactive role-play teaching method assists in strengthening the link between practical and theoretical skills, which is especially relevant in teaching of palliative medicine. The paper is aimed at evaluation of the possibility of improving the effectiveness of the training of medical interns, using the role-play technique. To evaluate the impact of such interactive teaching methods as role- play in teaching of palliative care, we analyzed the effectiveness of teaching of 162 interns from 2014 to 2020. Subgroup I (n=82) involved medical interns who had in-class experience with role play technique. Subgroup II (n=80) involved interns for whom role-play teaching approach was not utilized. The findings of the analysis have revealed that the use of role-play teaching model in Subgroup I increased the academic success rate of interns to 94.7% (p≤0.05) in contrast to 81.3% (p≤0.2) in Subgroup II. Moreover, interns of Subgroup I rated the work of the teacher higher (8.2 points), compared to Subgroup II, where the score was 6.9 points. Therefore, the use of role-play as one of the interactive teaching methods in the postgraduate training of interns can improve the basic knowledge in patient care management in both theoretical and practical part of the training, which further improves professional progress and necessitates greater use of this method of interactive training in the postgraduate study

ОСОБЕННОСТИ ОСТРЫХ НАРУШЕНИЙ МОЗГОВОГО КРОВООБРАЩЕНИЯ В РОССИЙСКОЙ ФЕДЕРАЦИИ И КИТАЙСКОЙ НАРОДНОЙ РЕСПУБЛИКЕ (по данным нескольких крупных сосудистых центров)

The study focuses on comparison and analysis of the work of big stroke units in the Russian Federation and the People’s Republic of China specialized in the medical care for patients with acute stroke. 522 patients were surveyed in Russia’s and China’s regional stroke units. In the Russian Federation, patients being treated in the «City Hospital No.26» (SaintPetersburg) took part in the study. In China patients of the First Affiliated Hospital of the Chongqing Medical University, Central Hospital Jiang jin, Regional People’s Hospital Yubei district, Regional People’s Hospital Bishan (Chongqing Province). The analysis of differences was performed by the following parameters: personality traits, age, gender, level of education, income, health insurance category, profession, employment, professional activities over the last year, place of residence of the patient, features of the stroke, time during the first symptoms of stroke to hospitalization, kinds of medical services, the main risk factors and value of prevention before stroke.Исследование посвящено сравнительному анализу работы крупных сосудистых центров в Российской Федерации и Китайской Народной Республике по оказанию помощи пациентам с острым нарушением мозгового кровообращения (ОНМК). Был проведен опрос 522 пациентов в региональных сосудистых центрах РФ и КНР. В РФ в исследовании приняли участие пациенты, находящиеся на лечении в СПбГБУЗ «Городская больница № 26»; в КНР – пациенты Первой клинической больницы медицинского университета Чунцина, Центральной больницы Цзян Цзинь, Региональной народной больницы Юйбэй, Региональной народной больницы Бишань (провинция Чунцин). Был проведен анализ различий по следующим показателям: личностные факторы пациента, возраст, пол, уровень образования, уровень дохода, вид медицинского страхования, профессия, занятость, профессиональная деятельность в течение последнего года, место жительства пациента, особенности заболевания, время с момента появления первых симптомов до госпитализации, спектр оказываемых медицинских услуг, основные факторы риска и объем профилактики инсульта до заболевания

Van der Waals-Casimir-Polder interaction of an atom with a composite surface

We study the dispersion interaction of the van der Waals and Casimir-Polder (vdW-CP) type between a neutral atom and the surface of a metal by allowing for nonlocal electrodynamics, i.e. electron diffusion. We consider two models: (i) bulk diffusion, and (ii) diffusion in a surface charge layer. In both cases the transition to a semiconductor is continuous as a function of the conductivity, unlike the case of a local model. The relevant parameter is the electric screening length and depends on the carrier diffusion constant. We find that for distances comparable to the screening length, vdW-CP data can distinguish between bulk and surface diffusion, hence it can be a sensitive probe for surface states.Comment: v2: expanded references, statements on current status in the field. 10 pages, 6 figure