THE DEPENDENCE OF THE CHAIN BRANCHING DEGREE ON MOLECULAR WEIGHT: FRACTAL ANALYSIS

The fractal analysis methodology allows the clear structural identification of both chemical and physical factors controlling a chain branching degree. The effective number of branching centers per one macromolecule m is controlled by four factors: polymer molecular weight, MW, maximal “chemical” density of reactive centers, cch, dimension of non-screening surface of macromolecular coil, du, and its fractal dimension, D. The presented research allows the determination of the critical value, Dcr = 1.10, the lower of which branching degree is equal to zero (i.e., branching does not occur

The interaction of dark matter cusp with the baryon component in disk galaxies

In this paper we examine the effect of the formation and evolution of the disk galaxy on the distribution of dark halo matter. We have made simulations of isolated dark matter (DM) halo and two component (DM + baryons). N-body technique was used for stellar and DM particles and TVD MUSCL scheme for gas-dynamic simulations. The simulations include the processes of star formation, stellar feedback, heating and cooling of the interstellar medium. The results of numerical experiments with high spatial resolution let us to conclude in two main findings. First, accounting of star formation and supernova feedback resolves the so-called problem of cusp in distribution of dark matter predicted by cosmological simulations. Second, the interaction of dark matter with dynamic substructures of stellar and gaseous galactic disk (e.g., spiral waves, bar) has an impact on the shape of the dark halo. In particular, the in-plane distribution of dark matter is more symmetric in runs, where the baryonic component was taken into account.Comment: 7 pages, 6 figure

Scanning MOKE investigation of ion-beam-synthesized silicide films

Fe ions with an energy of 40 keV were implanted into Si plates with the fluence varying in the range of (1.6-3.0) × 10 17 ion/cm 2 in the external magnetic field. Scanning magnetooptical Kerr effect (MOKE) studies have shown that all samples possess uniaxial anisotropy. Both the coercive field and the anisotropy field increase with fluence. It was suggested that induced anisotropy is caused by inverse magnetostriction. © 2011 Elsevier B.V. All rights reserved

BVRI Surface Photometry of Isolated Spiral Galaxies

A release of multicolor broad band (BVRI) photometry for a subsample of 44 isolated spirals drawn from the Catalogue of Isolated Galaxies (CIG) is presented. Total magnitudes and colors at various circular apertures, as well as some global structural/morphological parameters are estimated. Morphology is reevaluated through optical and sharp/filtered R band images, (B-I) color index maps, and archive near-IR JHK images from the Two-Micron Survey. The CAS structural parameters (Concentration, Asymmetry, and Clumpiness) were calculated from the images in each one of the bands. The fraction of galaxies with well identified optical/near-IR bars (SB) is 63%, while a 17% more shows evidence of weak or suspected bars (SAB). The sample average value of the maximum bar ellipticity is 0.4. Half of the galaxies in the sample shows rings. We identify two candidates for isolated galaxies with disturbed morphology. The structural CAS parameters change with the observed band, and the tendencies they follow with the morphological type and global color are more evident in the redder bands. In any band, the major difference between our isolated spirals and a sample of interacting spirals is revealed in the A-S plane. A deep and uniformly observed sample of isolated galaxies is intended for various purposes including (i) comparative studies of environmental effects, (ii) confronting model predictions of galaxy evolution and (iii) evaluating the change of galaxy properties with redshift.Comment: 44 pages, 9 figures and 7 tables included. To appear in The Astronomical Journal. For the 43 appendix figures 4.1-4.43 see http://www.astroscu.unam.mx/~avila/Figs4.1_4.43.tar.gz (7.2 Mb tar.gz file

The relationship of fracture toughness coefficients and geophysical characteristics of rocks of hydrocarbon deposits

This paper contains the results of laboratory tests to determine the fracture toughness coefficient KIC of rocks for terrigenous and carbonate objects by three methods. The tests were carried out by different methods due to the lack of a standard method for determining the fracture toughness characteristics of rocks in Russia. We used the following methods for determining the KIC coefficient: the extension of core specimens with an annular fracture, the action of a concentrated load on a beam specimen with a fracture and the method of bending semi-circular samples with a fracture according to ISRM recommendations. The paper presents the relationship of the fracture toughness coefficients with the P-wave velocity and porosity. The obtained dependencies characterize the general trend of changing for the studied parameter and can be used in the design of hydraulic fracturing in the fields for which tests were conducted

Merging of Components in Close Binaries: Type Ia Supernovae, Massive White Dwarfs, and Ap stars

The "Scenario Machine" (a computer code designed for studies of the evolution of close binaries) was used to carry out a population synthesis for a wide range of merging astrophysical objects: main-sequence stars with main-sequence stars; white dwarfs with white dwarfs, neutron stars, and black holes; neutron stars with neutron stars and black holes; and black holes with black holes.We calculate the rates of such events, and plot the mass distributions for merging white dwarfs and main-sequence stars. It is shown that Type Ia supernovae can be used as standard candles only after approximately one billion years of evolution of galaxies. In the course of this evolution, the average energy of Type Ia supernovae should decrease by roughly 10%; the maximum and minimum energies of Type Ia supernovae may differ by no less than by a factor of 1.5. This circumstance should be taken into account in estimations of parameters of acceleration of the Universe. According to theoretical estimates, the most massive - as a rule, magnetic - white dwarfs probably originate from mergers of white dwarfs of lower mass. At least some magnetic Ap and Bp stars may form in mergers of low-mass main sequence stars (<1.5 mass of the Sun) with convective envelopes.Comment: 15 pages, 4 figure

Нарушения функции внешнего дыхания при различных формах легочной патологии

The most common lung function abnormalities in patients with respiratory diseases have been reviewed in the article. Ventilation disorders with change in the lung volumes, bronchial obstruction and hypoxemia are typical for patients with pneumonia. Lung compliance reduction, inconsistency of ventilation, and ventilation perfusion mismatch could be found in chronic non-obstructive bronchitis. Chronic obstructive pulmonary disease is associated with bronchial obstruction which is defined as decreased forced expiratory volume for 1 sec (FEV1) and forced expiratory flows at different levels of forced vital capacity (FVC) and increased airway resistance. Asthma is associated with reversible change in expiratory flows, such as FEV1 and peak expiratory flow, due to bronchial hyperresponsiveness. Residual volume (RV) could increase in patients with acute asthma attack. Emphysema is characterized by changes in lung volumes, primarily due to increased RV; lung diffusing capacity (DLCO) could decrease and the lung perfusion could change. Mixed (obstructive and restrictive) lung ventilation disorders could be diagnosed in patients with chronic purulent lung diseases. Patients with disseminated lung lesions could demonstrate decreased lung compliance, reduced lung volumes, decreased DLCO and hypoxemia without hypercapnia.Представлены наиболее типичные нарушения функции внешнего дыхания (ФВД) у больных пульмонологического профиля. При пневмонии нарушается вентиляция, страдают легочные объемы, имеют место нарушения бронхиальной проходимости, развивается артериальная гипоксемия. При хроническом необструктивном бронхите выявляются некоторое снижение растяжимости легких, нарушения равномерности вентиляции, признаки нарушения вентиляционно-перфузионных отношений. У пациентов с хронической обструктивной болезнью легких (ХОБЛ) бронхиальная обструкция имеет генерализованный характер, что выражается в снижении объема форсированного выдоха за 1-ю секунду (ОФВ1), уменьшении объемной скорости потока на различных уровнях форсированной жизненной емкости легких и увеличении бронхиального сопротивления. Существенные изменения претерпевают легочные объемы, особенно остаточный объем (ООЛ) и общая емкость (ОЕЛ) легких. При бронхиальной астме (БА) регистрируется преходящее лабильное изменение скоростных параметров спирометрии (ОФВ1, пиковая скорость выдоха), обусловленное бронхиальной гиперреактивностью. В период обострения БА также регистрируется увеличение ООЛ. У лиц с эмфиземой легких нарушения ФВД проявляются изменением структуры ОЕЛ за счет увеличения ООЛ. Снижается диффузионная способность легких (DLCO), отмечаются нарушения перфузии. У пациентов с хроническими нагноительными заболеваниями легких отмечаются нарушения вентиляции по смешанному типу (рестриктивные и обструктивные). Для диссеминированных заболеваний легких характерно уменьшение растяжимости легких и легочных объемов, снижение DLCO, развитие артериальной гипоксемии (без гиперкапнии)

The Multiplicity of Main Sequence Turnoffs in Globular Clusters

We present color-magnitude diagrams of globular clusters for models with self-enrichment and pre-enrichment. The models with self-enrichment turn out to have two or more main sequence turnoff points in the color-magnitude diagram if the fraction of mass lost by the globular cluster under supernova explosions does not exceed 95-97%. The models with pre-enrichment can have only one main sequence turnoff point. We argue that the cluster wCen evolved according to a self-enrichment scenario.Comment: 13 pages, 7 figure

Role of stem cell transplant in CD30+ PTCL following frontline brentuximab vedotin plus CHP or CHOP in ECHELON-2

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of aggressive non-Hodgkin lymphomas, the majority of which have high relapse rates following standard therapy. Despite use of consolidative stem cell transplant (SCT) following frontline therapy, there remains no consensus on its utility. The double-blind randomized phase 3 ECHELON-2 study (#NCT01777152; clinicaltrials.gov) demonstrated improved progression-free survival (PFS) and overall survival with frontline brentuximab vedotin plus cyclophosphamide, doxorubicin, and prednisone (A+CHP). Herein, we conducted an exploratory subgroups analysis of the impact of consolidative SCT on PFS in patients with previously untreated CD30+ PTCL (ALK- anaplastic large cell lymphoma [ALCL] and non-ALCL) who were in complete response (CR) after frontline treatment with A+CHP or cyclophosphamide, doxorubicin, vincristine, and prednisone. Median PFS follow-up was 47.57 months. The PFS hazard ratio was 0.36, equating to a 64% reduction in the risk of a PFS event in patients who underwent SCT. The median PFS in patients who underwent SCT was not reached, vs 55.66 months in patients who did not undergo SCT. PFS results favored the use of SCT in both ALK- ALCL and non-ALCL subgroups. These data support the consideration of consolidative SCT in patients with CD30+PTCL who achieve CR following treatment with A+CHP