546 research outputs found
IMMUNOMODULATORY EFFECT OF SOTALOL HYDROHLORIDE UNDER ACUTE STRESS
It was established that acute stress in period induction of the local and systemic immune response to thymus-dependent antigen caused an inhibition of expression of delayed-type hypersensitivity reactions, did not effect on antibody production in the regional lymph node under the local response and suppressed of antibody production in the spleen under the systemic immune response. Administration of sotalol hydrochloride (antagonist of beta-adrenoceptors with peripheral action) canceled these changes, that points to participate in their implementation of immunosuppressive signals from the peripheral beta-adrenergic receptors
Mutual Fund Theorem for continuous time markets with random coefficients
We study the optimal investment problem for a continuous time incomplete
market model such that the risk-free rate, the appreciation rates and the
volatility of the stocks are all random; they are assumed to be independent
from the driving Brownian motion, and they are supposed to be currently
observable. It is shown that some weakened version of Mutual Fund Theorem holds
for this market for general class of utilities; more precisely, it is shown
that the supremum of expected utilities can be achieved on a sequence of
strategies with a certain distribution of risky assets that does not depend on
risk preferences described by different utilities.Comment: 17 page
Clinical Experience of Luminescent Diagnostics of Precancerous Diseases and Cervical Cancer
The article summarizes the experience of using luminescent diagnostics with the use of ytterbium porphyrin complexes in gynecology and oncology. A pharmaceutical composition based on the Yb complex of 2,4-dimethoxyhematoporphyrin IX was used as the luminescent markers within the infrared range. The determination of luminescence characteristics (luminescence intensity) was carried out using a laserfiber fluorimeter in the range of 900-1100 nm. A new method for diagnosis of cervical disease has been proposed. The method of luminescent diagnostics allows to conduct a survey of a large number of patients in a short time. The method of luminescent diagnostics using the ytterbium complexes of porphyrins is not invasive. The method can be used as a screening. Differences between normal and pathologically altered cervical tissue have been identified and differences between pathological changes in the cervix HSIL (CIN II, CIN III) and cervical cancer are reliable.
Keywords: Cervical cancer, squamous cell carcinoma, diagnosis of cervical cancer, squamous intraepithelial lesions of high grade – HSIL, luminescent diagnostics, luminescing in the near infrared (NIR) spectral region, porphyrins, ytterbium complexes of porphyrins
Therapeutic complement targeting in ANCA-associated vasculitides and thrombotic microangiopathy
Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) are a group of systemic autoimmune disorders characterized by necrotizing inflammation of medium-to-small vessels, a relative paucity of immune deposits, and an association with detectable circulating ANCAs. AAVs include granulomatosis with polyangiitis (renamed from Wegener's granulomatosis), microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome). Until recently, AAVs have not been viewed as complement-mediated disorders. However, recent findings predominantly from animal studies demonstrated a crucial role of the complement system in the pathogenesis of AAVs. Complement activation or defects in its regulation have been described in an increasing number of acquired or genetically driven forms of thrombotic microangiopathy. Coinciding with this expanding spectrum of complement-mediated diseases, the question arises as to which AAV patients might benefit from a complement-targeted therapy. Therapies directed against the complement system point to the necessity of a genetic workup of genes of complement components and regulators in patients with AAV. Genetic testing together with pluripotent stem cells and bioinformatics tools may broaden our approach to the treatment of patients with aggressive forms of AAV
Differential Form Valued Forms and Distributional Electromagnetic Sources
Properties of a fundamental double-form of bi-degree for are
reviewed in order to establish a distributional framework for analysing
equations of the form where
is the Hodge-de Rham operator on forms on .
Particular attention is devoted to singular distributional solutions that arise
when the source is a singular form distribution. A constructive
approach to Dirac distributions on (moving) submanifolds embedded in is developed in terms of (Leray) forms generated by the geometry of the
embedding. This framework offers a useful tool in electromagnetic modeling
where the possibly time dependent sources of certain physical attributes, such
as electric charge, electric current and polarization or magnetization, are
concentrated on localized regions in space.Comment: 40 page
High frequency magnetic oscillations of the organic metal -(ET)ZnBr(CHCl) in pulsed magnetic field of up to 81 T
De Haas-van Alphen oscillations of the organic metal
-(ET)ZnBr(CHCl) are studied in pulsed magnetic
fields up to 81 T. The long decay time of the pulse allows determining reliable
field-dependent amplitudes of Fourier components with frequencies up to several
kiloteslas. The Fourier spectrum is in agreement with the model of a linear
chain of coupled orbits. In this model, all the observed frequencies are linear
combinations of the frequency linked to the basic orbit and to the
magnetic-breakdown orbit .Comment: 6 pages, 4 figure
Luminescence in anion-deficient hafnia nanotubes
Hafnia-based nanostructures and other high-k dielectrics are promising
wide-gap materials for developing new opto- and nanoelectronics devices. They
possess a unique combination of physical and chemical properties such as
insensitivity to electrical and optical degradation, radiation damage
stability, a high specific surface area, and an increased concentration of the
appropriate active electron-hole centers. The present paper aims to investigate
the structural, optical, and luminescent properties of anodized
non-stoichiometric nanotubes. As-grown amorphous hafnia nanotubes and
nanotubes annealed at 700{\deg}C with a monoclinic crystal lattice served as
samples. It has been shown that the bandgap for direct allowed
transitions amounts to eV for amorphous and eV for
monoclinic nanotubes. For the first time, we have studied the features of the
intrinsic cathodoluminescence and photoluminescence of the obtained nanotubular
structures with an atomic deficiency in the anion sublattice at
temperatures of 10 and 300 K. A broad emission band with a maximum of 2.3-2.4
eV has been revealed. We have also conducted an analysis of the kinetic
dependencies of the observed photoluminescence for synthesized samples
in the millisecond range at room temperature. It showed that there are several
types of optically active capture and emission centers based on vacancy states
in the and positions with different coordination numbers and
a varied number of localized charge carriers (, , and ). The
uncovered regularities can be used to optimize the functional characteristics
of developed-surface luminescent media based on nanotubular and nanoporous
modifications of hafnia.Comment: 15 pages, 6 figures, 3 tables, 50 reference
Quantum oscillations in the linear chain of coupled orbits: the organic metal with two cation layers theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2))
Analytical formulae for de Haas-van Alphen (dHvA) oscillations in linear
chain of coupled two-dimensional (2D) orbits (Pippard's model) are derived
systematically taking into account the chemical potential oscillations in
magnetic field. Although corrective terms are observed, basic (alpha) and
magnetic breakdown-induced (beta and 2beta - alpha) orbits can be accounted for
by the Lifshits-Kosevich (LK) and Falicov-Stachowiak semiclassical models in
the explored field and temperature ranges. In contrast, the 'forbidden orbit'
beta - alpha amplitude is described by a non-LK equation involving a product of
two classical orbit amplitudes. Furthermore, strongly non-monotonic field and
temperature dependence may be observed for the second harmonics of basic
frequencies such as 2alpha and the magnetic breakdown orbit beta + alpha,
depending on the value of the spin damping factors. These features are in
agreement with the dHvA oscillation spectra of the strongly 2D organic metal
theta- theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2)).Comment: to be published in Europhysics Letters (2012
Diffuse-Charge Dynamics in Electrochemical Systems
The response of a model micro-electrochemical system to a time-dependent
applied voltage is analyzed. The article begins with a fresh historical review
including electrochemistry, colloidal science, and microfluidics. The model
problem consists of a symmetric binary electrolyte between parallel-plate,
blocking electrodes which suddenly apply a voltage. Compact Stern layers on the
electrodes are also taken into account. The Nernst-Planck-Poisson equations are
first linearized and solved by Laplace transforms for small voltages, and
numerical solutions are obtained for large voltages. The ``weakly nonlinear''
limit of thin double layers is then analyzed by matched asymptotic expansions
in the small parameter , where is the
screening length and the electrode separation. At leading order, the system
initially behaves like an RC circuit with a response time of
(not ), where is the ionic diffusivity, but nonlinearity
violates this common picture and introduce multiple time scales. The charging
process slows down, and neutral-salt adsorption by the diffuse part of the
double layer couples to bulk diffusion at the time scale, . In the
``strongly nonlinear'' regime (controlled by a dimensionless parameter
resembling the Dukhin number), this effect produces bulk concentration
gradients, and, at very large voltages, transient space charge. The article
concludes with an overview of more general situations involving surface
conduction, multi-component electrolytes, and Faradaic processes.Comment: 10 figs, 26 pages (double-column), 141 reference
Anomalous terahertz photoconductivity caused by the superballistic flow of hydrodynamic electrons in graphene
Light incident upon materials can induce changes in their electrical
conductivity, a phenomenon referred to as photoresistance. In semiconductors,
the photoresistance is negative, as light-induced promotion of electrons across
the band gap enhances the number of charge carriers participating in transport.
In superconductors, the photoresistance is positive because of the destruction
of the superconducting state, whereas in normal metals it is vanishing. Here we
report a qualitative deviation from the standard behavior in metallic graphene.
We show that Dirac electrons exposed to continuous wave (CW) terahertz (THz)
radiation can be thermally decoupled from the lattice by 50~K which activates
hydrodynamic electron transport. In this regime, the resistance of graphene
constrictions experiences a decrease caused by the THz-driven superballistic
flow of correlated electrons. We analyze the dependencies of the negative
photoresistance on the carrier density, and the radiation power and show that
our superballistic devices operate as sensitive phonon-cooled bolometers and
can thus offer a picosecond-scale response time. Beyond their fundamental
implications, our findings underscore the practicality of electron
hydrodynamics in designing ultra-fast THz sensors and electron thermometers.Comment: 7 pages, 3 figure
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