Current-controlled sedimentation in the north-western Weddell Sea

The sedimentary basins of the north-western Weddell Sea are characterized by a variety of contourite drifts. This study is aimed at their identification, spatial mapping and temporal evolution and based on the integration of a large amount of seismic data collected by different countries including the recent data of the Russian Antarctic Expedition. Most of the drifts in the region being studied are classified as separated, confined, plastered or sheeted. The chain of sediment wave fields is mapped in the western and northern Powell Basin. The earliest contourite drifts started to form in the Early Miocene or, possibly, in the Late Oligocene. The changes in the depositional pattern in the Middle Miocene and then in the Late Pliocene are thought to have resulted from successive intensification of the bottom currents. Контуритовые наносы, формируемые придонными течениями, могут использоваться для изучения циркуляции водных масс, так как по их параметрам и характеру распространения можно судить о направленности и относительной энергии придонных течений. В данной работе рассматриваются контуритовые наносы в северо-западной части моря Уэдделла, приводится схема распространения наносов и их классификация, а также реконструируется циркуляция водных масс в глубоководных бассейнах района. Исследования основаны на обобщении и интерпретации сейсмических данных отечественных и зарубежных экспедиций, большая часть которых доступна из международной библиотеки сейсмических данных по Антарктике. В результате анализа сейсмических данных в районе исследований в диапазоне глубин от 2000 до 4500 м выявлены отделенные, ограниченные, пластерные и покровные контуритовые наносы.  Зарождение донных течений в северо-западной части моря Уэдделла  началось с раскрытия бассейна Пауэлл, и развитие самых ранних  контуритовых наносов предполагается 24–23 млн лет назад. В среднем миоцене и в позднем плиоцене отмечается усиление интенсивности донных течение и более широкое развитие контуритовых наносов.

Kharkiv region of Ukraine in the aspect of a polycentric development model

This article is devoted to the analysis of a model of regional development of Kharkiv region of Ukraine, which is monocentric, and the rationale for the formation of polycentrism in the region. The city of Kharkiv and urban areas as centers of growth in the region are considered in the articl

Transport properties of the azimuthal magnetorotational instability

The magnetorotational instability (MRI) is thought to be a powerful source of turbulence in Keplerian accretion disks. Motivated by recent laboratory experiments, we study the MRI driven by an azimuthal magnetic field in an electrically conducting fluid sheared between two concentric rotating cylinders. By adjusting the rotation rates of the cylinders, we approximate angular velocity profiles ω ∝ r q . We perform direct numerical simulations of a steep profile close to the Rayleigh line q & −2 and a quasiKeplerian profile q ≈ −3/2 and cover wide ranges of Reynolds (Re ≤ 4 · 104 ) and magnetic Prandtl numbers (0 ≤ Pm ≤ 1). In the quasi-Keplerian case, the onset of instability depends on the magnetic Reynolds number, with Rmc ≈ 50, and angular momentum transport scales as √ PmRe2 in the turbulent regime. The ratio of Maxwell to Reynolds stresses is set by Rm. At the onset of instability both stresses have similar magnitude, whereas the Reynolds stress vanishes or becomes even negative as Rm increases. For the profile close to the Rayleigh line, the instability shares these properties as long as Pm & 0.1, but exhibits a markedly different character if Pm → 0, where the onset of instability is governed by the Reynolds number, with Rec ≈ 1250, transport is via Reynolds stresses and scales as Re2 . At intermediate Pm = 0.01 we observe a continuous transition from one regime to the other, with a crossover at Rm = O(100). Our results give a comprehensive picture of angular momentum transport of the MRI with an imposed azimuthal field

Differential diagnosis and effective therapy for sore throat

Sore throat is a common complaint, which can be caused by a typical viral pharyngitis, or it can be rooted in a life-threatening disease such as epiglottitis or inflammation of the cellular spaces in the throat and neck. The doctor should take a closer look at a patient with a sore throat, immediately make a differential diagnosis and prescribe adequate treatment, including surgical intervention, if necessary.The article discusses the most common causes of a sore throat, including various types of pharyngitis, paratonsillar abscess, parapharyngeal abscess, retropharyngeal abscess, epiglottitis.Viral pharyngitis has a favourable prognosis, resolves without intervention and complications, but bacterial and fungal pharyngitis have a more severe course. Streptococcal pharyngitis caused by group A в-hemolytic streptococcus holds a dominant position in bacterial etiology and requires the use of antibiotic therapy. The differential diagnosis of streptococcal pharyngitis is based on the modified Centor scores in the routine clinical practice. Antibiotic therapy for streptococcal pharyngitis includes a 10-day course of unprotected penicillins. If a patient has an allergic reaction to penicillins, it is recommended to use clindamycin or clarithromycin. The surgical intervention combined with intramuscular or intravenous antibiotic therapy is recommended for the treatment of purulent processes in the cellular spaces of the neck. These diseases can have life-threatening complications, which include neurological damage, the spread of purulent process in the mediastinum with the development of mediastinitis, laryn-geal stenosis, sepsis, necrotizing fasciitis, jugular vein thrombosis and erosion of the carotid artery. The third generation cephalosporins and protected penicillins are recommended for the treatment of epiglottitis, and respiratory fluoroquinolones are used, if a patient has a history of allergic reactions to penicillins. In severe cases with symptoms of stenosis, intubation can be performed in addition to the use of antibiotics

Helium Porosity Formation in Vanadium Alloys of V-Ti-Cr, V-W-Zr and V-W-Ta Systems in Comparison with Binary Alloys

Vanadium alloys are considered candidates for use as structural materials of fusion reactors. A large amount of helium will be accumulated in such materials. The presence of helium in the materials may result in gas swelling. This paper presents the results on helium porosity formation researches in V–Ti–Cr, V–W–Zr and V–W–Ta alloys obtained by means of TEM. Samples were irradiated by 40 keV Не+ ions up to dose of 5 ⋅ 1020m−2 at 923 K. Alloy V–4%Ti–4%Cr has a smallest helium swelling among the ternary alloys and its swelling is significantly lower than swelling of dual V–Ti and V–Cr alloys. The swelling of the ternary V–2%W–1%Zr alloy is more than 3 times less than the swelling of vanadium, several times less than that of V–W alloys and slightly lower than the swelling of V– Zr alloys. Swelling increases by a factor of 1.5 with increasing of Zr content to 2% in the ternary V–2%W–1%Zr alloy. Similarly, gas swelling of ternary V–2%W–1%Ta alloy is significantly lower than that for binary V–W and V–Ta alloys. Assumptions are made about the possible mechanisms of the effect of alloying elements in vanadium on helium porosity formation. Keywords: vanadium alloys, swelling, helium, radiation resistance

On the relationship between auroral and nebular oxygen line intensities in spectra of HII regions

We investigate relationships between observed auroral and nebular oxygen line fluxes in spectra of HII regions. We find a relation that is metallicity-dependent at low metallicities, but becomes independent of metallicity (within the uncertainties of the available data) above 12+logO/H ~ 8.25, i.e. there is one-to-one correspondance (the ff - relation) between auroral and nebular oxygen line fluxes in spectra of high-metallicity HII regions. The ff - relation allows one to estimate the flux in the auroral line from strong oxygen line measurements. This solves the problem of the electron temperature (and, consequently, abundance) determination in high-metallicity HII regions. The ff - relation confirms the basic idea of the empirical method, proposed by Pagel et al. (1979) a qurter of a century ago, that the oxygen abundance in HII region can be estimated from the strong oxygen lines measurements only.Comment: 4 pages, 2 figures, accepted for publication in Astronomy and Astrophysic

Study of psychological status of tsu students from exercise therapy group

The present article contains the results of ascertaining study, aimed at identification of the psychological characteristics of students engaged in groups of exercise therapy. It has been established that students with poor health differ greatly in psychometric characteristics from the group of students who do not have any problems with their health. These differences are most pronounced in the findings obtained by means of questionnaires of constructive thinking and level of subjective control. Students who train in the groups of exercise therapy, need special forms of organization of the educational process involving psychological methods

Super Star Clusters in the Blue Dwarf Galaxy UM 462

I present optical observations of the Blue Compact Dwarf Galaxy UM 462. The images of this galaxy show several bright compact sources. A careful study of these sources has revealed their nature of young Super Star Clusters. The ages determined from the analysis of the stellar continuum and $H\alpha$ are between few and few tens Myr. The total star formation taking place into the clusters is about 0.05 $\mathrm{M_{\odot}/yr}$. The clusters seem to be located at the edges of two large round-like structures, possibly shells originated in a previous episode of star formation. The sizes of the shells compare well with the ages of the clusters. Evidence for the presence of an evolved underlying stellar population is found.Comment: 8 pages, 6 figure

Mapping the properties of blue compact dwarf galaxies: integral field spectroscopy with PMAS

(Abridged) We perform integral field spectroscopy of a sample of Blue compact dwarf (BCD) galaxies with the aim of analyzing their morphology, the spatial distribution of some of their physical properties (excitation, extinction, and electron density) and their relationship with the distribution and evolutionary state of the stellar populations. Integral field spectroscopy observations of the sample galaxies were carried out with the Potsdam Multi-Aperture Spectrophotometer (PMAS) at the 3.5 m telescope at Calar Alto Observatory. An area 16 arcsec x 16 arcsec in size was mapped with a spatial sampling of 1 arcsec x 1 arcsec. We obtained data in the 3590-6996 Angstroms spectral range, with a linear dispersion of 3.2 Angstroms per pixel. From these data we built two-dimensional maps of the flux of the most prominent emission lines, of two continuum bands, of the most relevant line ratios, and of the gas velocity field. Integrated spectra of the most prominent star-forming regions and of whole objects within the FOV were used to derive their physical parameters and the gas metal abundances. Six galaxies display the same morphology both in emission line and in continuum maps; only in two objects, Mrk 32 and Tololo 1434+032, the distributions of the ionized gas and of the stars differ considerably. In general the different excitation maps for a same object display the same pattern and trace the star-forming regions, as expected for objects ionized by hot stars; only the outer regions of Mrk 32, I Zw 123 and I Zw 159 display higher [SII]/Halpha values, suggestive of shocks. Six galaxies display an inhomogeneous dust distribution. Regarding the kinematics, Mrk 750, Mrk 206 and I Zw 159 display a clear rotation pattern, while in Mrk 32, Mrk 475 and I Zw 123 the velocity fields are flat.Comment: 27 pages, 11 figures; Accepted for publication in A&