845 research outputs found
Methods of predicting relapsing hemorrhage.
In this article the authors presented their own original methods for predicting ulcerous gastroduodenal bleeding defended by Patent of Ukraine. The implementation of these procedures led to substantial lowing of recurrent hamorrhage rate – more than twice. All methods have pathogenetic foundation and are based on ulcerogenesis mechanisms revealed during the longlasting complex clinical and experimental research. In such a way surgeons obtain some possibilities of early diagnostics of bleeding relapses and adequate treatment and effective hemorrhage prevention accordingly.
Limit cycles of orthogonal projection onto the set of the most remote
The problem of finding the limit polygonal cycles of orthogonal projection onto the most remote set in the plane is discussed. As a simplest case we have considered projections onto the remote side of the triangle. A criterion of existence and analytical formulas for limit triangular cycles is described. We construct the set of initial points of the sequence converging to the triangular cycle. The examples of limit polygonal cycles are presented. Numerical calculations are performed.Рассмотрена задача нахождения предельных многоугольных циклов при ортогональном проектировании на наиболее удаленное множество из конечного набора выпуклых компактных множеств на плоскости. В качестве простейшего случая построены предельные циклы проектирования на наиболее удаленную сторону треугольника. Предложены критерий существования и аналитические формулы для предельных треугольных циклов. Описано множество начальных точек последовательности, сходящейся к треугольному циклу. Представлены примеры многоугольных циклических контуров. Проведены численные расчеты для треугольников
All-dielectric hybrid silicon/Ge2Sb2Te5 optical metasurfaces for tunable and switchable light control in the near infrared
This is the final version.We report a novel reconfigurable metasurface based on the combination of all-dielectric arrays of
silicon meta-atoms, with deeply subwavelength (< λ0/150) Ge2Sb2Te5 layers. Our approach allows to selectively
and individually control electric and magnetic resonances.Engineering and Physical Sciences Research Council (EPSRC
Methods of predicting relapsing hemorrhage.
In this article the authors presented their own original methods for predicting ulcerous gastroduodenal bleeding defended by Patent of Ukraine. The implementation of these procedures led to substantial lowing of recurrent hamorrhage rate – more than twice. All methods have pathogenetic foundation and are based on ulcerogenesis mechanisms revealed during the longlasting complex clinical and experimental research. In such a way surgeons obtain some possibilities of early diagnostics of bleeding relapses and adequate treatment and effective hemorrhage prevention accordingly
Photoconductivity of CdS-CdSe granular films: influence of microstructure
We study experimentally the photoconductivity of CdS-CdSe sintered granular
films obtained by the screen printing method. We mostly focus on the
dependences of photoconductivity on film's microstructure, which varies with
changing heat-treatment conditions. The maximum photoconductivity is found for
samples with compact packing of individual grains, which nevertheless are
separated by gaps. Such a microstructure is typical for films heat-treated
during an intermediate (optimal) time. In order to understand whether the
dominant mechanism of charge transfer is identical with the one in
monocrystals, we perform temperature measurements of photoresistance.
Corresponding curves have the same peculiar nonmonotonic shape as in CdSe
monocrystals, from which we conclude that the basic mechanism is also the same.
It is suggested that the optimal heat-treatment time appears as a result of a
competition between two mechanisms: improvement of film's connectivity and its
oxidation. Photoresistance is also measured in vacuum and in helium atmosphere,
which suppress oxygen and water absorption/chemisorption at intergrain
boundaries. We demonstrate that this suppression increases photoconductivity,
especially at high temperatures.Comment: 12 pages, 8 figures, final versio
Vapour-liquid coexistence in many-body dissipative particle dynamics
Many-body dissipative particle dynamics is constructed to exhibit
vapour-liquid coexistence, with a sharp interface, and a vapour phase of
vanishingly small density. In this form, the model is an unusual example of a
soft-sphere liquid with a potential energy built out of local-density dependent
one-particle self energies. The application to fluid mechanics problems
involving free surfaces is illustrated by simulation of a pendant drop.Comment: 8 pages, 6 figures, revtex
BWO based imaging for control of MWCNTs polymer composites homogeneity
Terahertz imaging system based on backward wave oscillator for the defectoscopy of composites in the industry is presented. At a frequency of 874 GHz images of multiwall carbon nanotube agglomerates in a composite are obtained. The possibility of detecting inhomogeneities using level filtering is shown
Orbital Magnetoresistance in the LaSrCuO System
Measurements of resistivity, Hall effect, and magnetoresistance have been
made on seven c-axis oriented thin-film specimens of La(2-x)Sr(x)CuO(4) with
values of x from 0.048 to 0.275, and one specimen that also contains Nd. The
orbital magnetoresistance is found not to be proportional to the square of the
tangent of the Hall angle except for values of x near 0.15 above about 80K. For
smaller values of x the temperature dependence of the magnetoresistance is
different, but quite similar in the various specimens, in spite of large
differences in resistivity, Hall coefficient, and Hall angle.Comment: LaTeX, 14 pages, 4 embedded color eps figure
Structural phase control of (LaNdSr)CuO thin films by epitaxial growth technique
Epitaxial growth of (LaNdSr)CuO thin films was
studied by pulsed-laser deposition technique on three different substrates,
SrTiO (100), LaSrAlO (001), and YAlO (001). The
(Nd,Sr,Ce)CuO-type structure appears at the initial growth stage on
SrTiO (100) when the film is deposited under the growth conditions
optimized for (La,Sr)CuO. This (Nd,Sr,Ce)CuO-type structure can
be eliminated by increasing the substrate temperature and the laser repetition
frequency. Films on LaSrAlO (001) maintain a LaCuO-type structure
as bulk samples, but those on YAlO (001) show phase separation into
LaCuO- and NdCuO-type structures. Such complicated results are
explained in terms of the competition between lattice misfit and thermodynamic
conditions. Interestingly the films with LaCuO-type structure prepared
on SrTiO and LaSrAlO show different surface structures and transport
properties. The results indicate the possibility of controlling charge stripes
of (LaNdSr)CuO as was demonstrated in
(La,Ba)CuO thin films by Sato et al. (Phys. Rev. B {\bf 62}, R799
(2000)).Comment: 5 pages, 6 EPS figure, accepted for publication in Phys. Rev.
Natural chain-breaking antioxidants and their synthetic analogs as modulators of oxidative stress
Oxidative stress is associated with the increased production of reactive oxygen species or with a significant decrease in the effectiveness of antioxidant enzymes and nonenzymatic defense. The penetration of oxygen and free radicals in the hydrophobic interior of biological membranes initiates radical disintegration of the hydrocarbon “tails” of the lipids. This process is known as “lipid peroxidation”, and the accumulation of the oxidation products as peroxides and the alde-hydes and acids derived from them are often used as a measure of oxidative stress levels. In total, 40 phenolic antioxidants were selected for a comparative study and analysis of their chain-breaking antioxidant activity, and thus as modulators of oxidative stress. This included natural and natural-like ortho-methoxy and ortho-hydroxy phenols, nine of them newly synthesized. Applied experimental and theoretical methods (bulk lipid autoxidation, chemiluminescence, in silico methods such as density functional theory (DFT) and quantitative structure–activity relationship ((Q)SAR) modeling) were used to clarify their structure–activity relationship. Kinetics of non-inhibited and inhibited lipid oxidation in close connection with inhibitor transformation under oxidative stress is considered. Special attention has been paid to chemical reactions resulting in the initiation of free radicals, a key stage of oxidative stress. Effects of substituents in the side chains and in the phenolic ring of hydroxylated phenols and biphenols, and the concentration were discussed
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