25 research outputs found
Anti-corruption policy in a socio-cultural space: indicators and actual strategies
The paper proposes a discussion of an essence, modern interpretation and directions of counteraction to corruption interaction. The paper analyzes wide (sociological) and narrow (formal-legal) approaches to the interpretation of corruption interaction, examines the causes and forms that activate the development of corruption in the post-Soviet space. The authors singled out and analyzed key aspects of the modern anticorruption policy carried out in Russia at the beginning of the 21st century. The author's vision of the content of the anti-corruption legislation is separately argued, specific proposals are formulated to improve the legislation in the conditions of an unstable legal system and a transitional state, and the basic guidelines for its further development are determined
Depth-Resolved Composition and Electronic Structure of Buried Layers and Interfaces in a LaNiO/SrTiO Superlattice from Soft- and Hard- X-ray Standing-Wave Angle-Resolved Photoemission
LaNiO (LNO) is an intriguing member of the rare-earth nickelates in
exhibiting a metal-insulator transition for a critical film thickness of about
4 unit cells [Son et al., Appl. Phys. Lett. 96, 062114 (2010)]; however, such
thin films also show a transition to a metallic state in superlattices with
SrTiO (STO) [Son et al., Appl. Phys. Lett. 97, 202109 (2010)]. In order to
better understand this transition, we have studied a strained LNO/STO
superlattice with 10 repeats of [4 unit-cell LNO/3 unit-cell STO] grown on an
(LaAlO)(SrAlTaO) substrate using soft x-ray
standing-wave-excited angle-resolved photoemission (SWARPES), together with
soft- and hard- x-ray photoemission measurements of core levels and
densities-of-states valence spectra. The experimental results are compared with
state-of-the-art density functional theory (DFT) calculations of band
structures and densities of states. Using core-level rocking curves and x-ray
optical modeling to assess the position of the standing wave, SWARPES
measurements are carried out for various incidence angles and used to determine
interface-specific changes in momentum-resolved electronic structure. We
further show that the momentum-resolved behavior of the Ni 3d eg and t2g states
near the Fermi level, as well as those at the bottom of the valence bands, is
very similar to recently published SWARPES results for a related
LaSrMnO/SrTiO superlattice that was studied using the
same technique (Gray et al., Europhysics Letters 104, 17004 (2013)), which
further validates this experimental approach and our conclusions. Our
conclusions are also supported in several ways by comparison to DFT
calculations for the parent materials and the superlattice, including
layer-resolved density-of-states results
Using Heavy Quark Spin Symmetry in Semileptonic Decays
The form factors parameterizing the B_c semileptonic matrix elements can be
related to a few invariant functions if the decoupling of the spin of the heavy
quarks in B_c and in the mesons produced in the semileptonic decays is
exploited. We compute the form factors as overlap integral of the meson
wave-functions obtained using a QCD relativistic potential model, and give
predictions for semileptonic and non-leptonic B_c decay modes. We also discuss
possible experimental tests of the heavy quark spin symmetry in B_c decays.Comment: RevTex, 22 pages, 2 figure
Spallative ablation of dielectrics by X-ray laser
Short laser pulse in wide range of wavelengths, from infrared to X-ray,
disturbs electron-ion equilibrium and rises pressure in a heated layer. The
case where pulse duration is shorter than acoustic relaxation time
is considered in the paper. It is shown that this short pulse may cause
thermomechanical phenomena such as spallative ablation regardless to
wavelength. While the physics of electron-ion relaxation on wavelength and
various electron spectra of substances: there are spectra with an energy gap in
semiconductors and dielectrics opposed to gapless continuous spectra in metals.
The paper describes entire sequence of thermomechanical processes from
expansion, nucleation, foaming, and nanostructuring to spallation with
particular attention to spallation by X-ray pulse
Generalized Chaplygin gas model: Cosmological consequences and statefinder diagnosis
The generalized Chaplygin gas (GCG) model in spatially flat universe is
investigated. The cosmological consequences led by GCG model including the
evolution of EoS parameter, deceleration parameter and dimensionless Hubble
parameter are calculated. We show that the GCG model behaves as a general
quintessence model. The GCG model can also represent the pressureless CDM model
at the early time and cosmological constant model at the late time. The
dependency of transition from decelerated expansion to accelerated expansion on
the parameters of model is investigated. The statefinder parameters and
in this model are derived and the evolutionary trajectories in plane are
plotted. Finally, based on current observational data, we plot the evolutionary
trajectories in and planes for best fit values of the parameters of
GCG model. It has been shown that although, there are similarities between GCG
model and other forms of chaplygin gas in statefinder plane, but the distance
of this model from the CDM fixed point in diagram is shorter
compare with standard chaplygin gas model.Comment: 10 pages, 5 figures, accepted in Astrophys Space Sci. (2011
Green function techniques in the treatment of quantum transport at the molecular scale
The theoretical investigation of charge (and spin) transport at nanometer
length scales requires the use of advanced and powerful techniques able to deal
with the dynamical properties of the relevant physical systems, to explicitly
include out-of-equilibrium situations typical for electrical/heat transport as
well as to take into account interaction effects in a systematic way.
Equilibrium Green function techniques and their extension to non-equilibrium
situations via the Keldysh formalism build one of the pillars of current
state-of-the-art approaches to quantum transport which have been implemented in
both model Hamiltonian formulations and first-principle methodologies. We offer
a tutorial overview of the applications of Green functions to deal with some
fundamental aspects of charge transport at the nanoscale, mainly focusing on
applications to model Hamiltonian formulations.Comment: Tutorial review, LaTeX, 129 pages, 41 figures, 300 references,
submitted to Springer series "Lecture Notes in Physics
First clinical experience of venous reconstruction with autologous vascular prosthesis from the sickle ligament of the liver with partial portosystemic bypass surgery
AiM oF StUDy Presentation of our own first clinical experience of venous reconstruction in portosystemic bypass surgery with the use of autologous vascular prostheses of the falciform ligament of the liver in the splenorenal position in a patient with portal hypertension syndrome in the outcome of liver cirrhosis of viral etiology. MAtERiAl AnD MEtHoDS Clinical observation of a patient born in 1978 with a diagnosis of cirrhosis of the liver of viral etiology (HCV) Child-Pugh A (6). MELD 10 points. Inactive phase. Intrahepatic portal hypertension syndrome. Esophageal varices grade III according to A. G. Scherzinger, gastric varices type I (GOV1) according to Sarin. Condition after repeated recurrent esophageal-gastric bleeding. Due to the high risk of another bleeding, as a secondary prevention of esophageal-gastric bleeding, partial splenorenal anastomosis of “H” - type was performed with the use of an autologous vascular prosthesis of the falciform ligament of the liver in the splenorenal position. RESUltS A flap measuring 60.0x20.0 mm was cut from the falciform ligament of the patient’s liver. From the latter, after adjusting the size of the graft to the individual needs of the patient, an autologous conduit was formed. It was used as an insert in the formation of an “H” - type splenorenal anastomosis with the imposition of two end-to-side anastomoses between the splenic vein and one end of the conduit and between the left renal vein and the other end of the conduit. The patency of the anastomosis was checked using intraoperative sonography. In a satisfactory condition, the patient was discharged for outpatient follow-up treatment at the place of residence. At the moment of writing the article, the follow-up period was 8 months. The bleeding did not recur. No varicose veins were found in the esophagus and stomach during control endoscopic examinations. The patency of the splenorenal shunt was confirmed by ultrasound dopplerography. ConClUSion The first clinical experience of venous reconstruction with portosystemic bypass surgery using as a possible replacement of autologous vascular prostheses of the falciform ligament of the liver in the splenorenal position in a patient with portal hypertension syndrome in the outcome of cirrhosis of the liver of viral etiology gives hope for the possibility of further successful testing of this method of splenorenal bypass surgery to reduce the risk of bleeding from varicose veins
Clinical and anatomical substantiation of access to the splenic and left renal veins in the operation of distal splenorenal anastomosis
AIM oF StUDy Development in an anatomical experiment of a technique for operative access to the splenic and left renal veins during distal splenorenal bypass surgery with justification of the possibility of its successful application in clinical conditions. MAtERIAl AnD MEtHoDS In the conditions of an anatomical experiment on 40 unfixed corpses of adults of both genders, objective volumetric and spatial indicators in surgical wounds were studied in two variants of exposure of retroperitoneal space vessels, as the first stage of distal splenorenal anastomosis. In clinical conditions in 40 patients with portal hypertension of various genesis, during the operation of distal splenorenal anastomosis, the wide exposure of the anterior surface of the pancreas, spleen, left renal veins and most of their branches was performed using the original method of partial left - sided medial visceral rotation, followed by an objective assessment of the volume-spatial parameters of access. Measurements were performed using a medical goniometer in relation to the mobilized areas of the left renal and splenic veins. Statistical processing of the study results was carried out using the method of variation statistics. To identify statistically significant differences, the Student's t-test was used for disjoint samples. RESUltS An original method of operative access to the splenic and left renal veins was developed during the operation of distal splenorenal bypass by lifting the internal organs of the left flank of the abdominal cavity from the posterior abdominal wall and diverting them to the right. In the anatomical experiment in the original method of partial left-sided medial visceral rotation, all indicators were better (depth of the wound is less and the angles of operative activity and the inclination of the axis of operative activity - larger) than with a classic approach of intraoperative intraperitoneal access via transverse incision in the mesentery of the transverse colon. Despite the various variants of vascular architectonics and various anthropometric indicators of patients, there were no any forced refusal of distal splenorenal bypass surgery or unintentional damage to both the vessels themselves and the pancreas, specific complications associated with the implementation of the proposed operative approach to the vessels of the left retroperitoneal space, including damage to the spleen and ischemia of the descending colon, in any of 40 clinical cases. ConClUSIon The suggested option of operative access to the splenic, left renal veins and their branches at the first stage of performing distal splenorenal anastomosis in patients with portal hypertension of various genesis provides convenient spatial relations in the operating wound; creates comfortable conditions for performing the main surgical technique - applying vascular anastomosis; has a minimal risk of developing specific complications associated with the approach to the vessels of the left retroperitoneal space