86 research outputs found
Association between low-grade chronic inflammation and depressed left atrial compliance in heart failure with preserved ejection fraction : a retrospective analysis
Relationship between mitral leaflets angles, left ventricular geometry and mitral deformation indices in patients with ischemic mitral regurgitation: imaging by echocardiography and cardiac magnetic resonance
Chronic ischemic mitral regurgitation (IMR) is associated with a markedly worse prognosis after myocardial infarction (MI).The study aimed to evaluate the relationship between anterior and posterior mitral leaflet angle (MLA) values, left ventricle remodeling and severity of ischaemic mitral regurgitation (IMR). Methods: Forty-two patients (age 63.5 ± 9.7 years, 36 men) with chronic IMR (regurgitant volume, RV > 20 ml; >6 months after MI) underwent transthoracic echocardiography (TTE) and cardiovascular magnetic resonance (CMR) imaging. Anterior and posterior MLA, determined by echocardiography, were correlated with indices of LV remodeling, mitral apparatus deformation and IMR severity by CMR. The anterior and posterior MLA was 25.41 ± 4.28 and 38.37 ± 8.89° (mean ± SD). In 5 patients (11.9%) the posterior MLA was ≥45°. There was a significant correlation between anterior MLA and RV (r = 0.74, P = 0.01). For patients with RV > 30 ml this correlation was stronger (r = 0.97, P = 0.005) and, in addition, there was a correlation between the RV and posterior MLA (r = 0.90, P = 0.037), between tenting area and posterior MLA (r = 0.90, P = 0.04), and between tenting area and anterior MLA (r = 0.82, P = 0.08). With regard to LV remodeling parameters, there was weaker but significant correlation between posterior MLA and LV end-diastolic volume index (r = 0.35, P = 0.031), LV end-systolic volume index (r = 0.37, P = 0.021), stroke volume (r = 0.35, P = 0.03), sphericity index (r = 0.33, P = 0.041). Anterior MLA correlated with wall motion score index (r = 0.41, P = 0.019). Besides, there was a correlation between posterior MLA and left atrial volume (r = 0.41, P = 0.012). Measurement of anterior and posterior MLA may play an important role in evaluating patients with IMR
Relativistic Effects in the Scalar Meson Dynamics
A separable potential formalism is used to describe the and
interactions in the scalar-isoscalar states in the energy range
from the threshold up to 1.4 GeV. Introduction of relativistic
propagators into a system of Lippmann-Schwinger equations leads to a very good
description of the data ( per one degree of freedom). Three
poles are found in this energy region: fo(500) ( MeV,
MeV), fo(975) ( MeV, MeV) and
fo(1400) ( MeV, MeV). The fo(975) state can be
interpreted as a bound state. The fo(500) state may be
associated with the often postulated very broad scalar resonance under the
threshold (sometimes called or meson). The
scattering lengths in the and channels have also been
obtained. The relativistic approach provides qualitatively new results (e.g.
the appearance of the fo(500)) in comparison with previously used
nonrelativistic approach.Comment: 30 pages in LaTeX + 5 figures available on request. Preprint Orsay No
IPNO/TH 93-3
Realistic Equations of State for the Primeval Universe
Early universe equations of state including realistic interactions between
constituents are built up. Under certain reasonable assumptions, these
equations are able to generate an inflationary regime prior to the
nucleosynthesis period. The resulting accelerated expansion is intense enough
to solve the flatness and horizon problems. In the cases of curvature parameter
\kappa equal to 0 or +1, the model is able to avoid the initial singularity and
offers a natural explanation for why the universe is in expansion.Comment: 32 pages, 5 figures. Citations added in this version. Accepted EPJ
Epigenetic regulation of S100 protein expression
S100 proteins are small, calcium-binding proteins whose genes are localized in a cluster on human chromosome 1. Through their ability to interact with various protein partners in a calcium-dependent manner, the S100 proteins exert their influence on many vital cellular processes such as cell cycle, cytoskeleton activity and cell motility, differentiation, etc. The characteristic feature of S100 proteins is their cell-specific expression, which is frequently up- or downregulated in various pathological states, including cancer. Changes in S100 protein expression are usually characteristic for a given type of cancer and are therefore often considered as markers of a malignant state. Recent results indicate that changes in S100 protein expression may depend on the extent of DNA methylation in the S100 gene regulatory regions. The range of epigenetic changes occurring within the S100 gene cluster has not been defined. This article reviews published data on the involvement of epigenetic factors in the control of S100 protein expression in development and cancer
Influence of mitochondrial genome rearrangement on cucumber leaf carbon and nitrogen metabolism
The MSC16 cucumber (Cucumis sativus L.) mitochondrial mutant was used to study the effect of mitochondrial dysfunction and disturbed subcellular redox state on leaf day/night carbon and nitrogen metabolism. We have shown that the mitochondrial dysfunction in MSC16 plants had no effect on photosynthetic CO2 assimilation, but the concentration of soluble carbohydrates and starch was higher in leaves of MSC16 plants. Impaired mitochondrial respiratory chain activity was associated with the perturbation of mitochondrial TCA cycle manifested, e.g., by lowered decarboxylation rate. Mitochondrial dysfunction in MSC16 plants had different influence on leaf cell metabolism under dark or light conditions. In the dark, when the main mitochondrial function is the energy production, the altered activity of TCA cycle in mutated plants was connected with the accumulation of pyruvate and TCA cycle intermediates (citrate and 2-OG). In the light, when TCA activity is needed for synthesis of carbon skeletons required as the acceptors for NH4+ assimilation, the concentration of pyruvate and TCA intermediates was tightly coupled with nitrate metabolism. Enhanced incorporation of ammonium group into amino acids structures in mutated plants has resulted in decreased concentration of organic acids and accumulation of Glu
Estimation of the width of microfracture in coals
Na podstawie wykonanych analiz mikroszczelinowatości, przepuszczalności i porowatości wykonano analizę rozwartości mikroszczelin przy określonym ciśnieniu nadkładu. Wyliczono porowatość szczelinową oraz porowatość matrycy. Przepuszczalność analizowanych próbek węgli określono jako szczelinową i wyznaczono trzy charakterystyczne przebiegi zamykania się szczelin pod wpływem ciśnienia nadkładu.On the basis of performed analyzes of microfractures, permeabilities and porosities, the analysis of the microfracture width was done at a given overburden pressure. Fracture and matrix porosity were calculated. The permeability of the analyzed coal samples was determined as a fracture, and three characteristic courses of closing the fracture under the influence of overburden pressure were determined
Non-linear optimization methods for small earthquake locations
The problem of locating mine tremors using P-wave arrival times is revisited in the paper. A multidimensional, global, non-linear, constrained optimization method is used as a minimization algorithm for tremor location.In order to see the general properties of the minimized function a few images showing its basins of attractions have been constructed. These pictures enable us to choose efficient algorithms needed to solve location problems. The classical genetic algorithm, pure random search and the most efficient multistart algorithm have been tested. Local minimization methods should be introduced to the location procedure to increase the efficiency of tremor location
New interpretation of reservoir and filtration properties of the Carpathian sandstones
Na podstawie 388 próbek reprezentujących piaskowce karpackie wykonano analizy przepuszczalności intergranularnej, porowatości i przepuszczalności szczelinowej, analizy granulometryczne. Próbki te zostały poddane analizom pod względem procesów diagenetycznych i ich wpływu na właściwości zbiornikowe. Przestrzeń porowa piaskowców karpackich jest wykształcona w procesie przemian diagenetycznych porowatości pierwotnej. Dominującą rolę w jej ewolucji odegrała kompakcja mechaniczna i cementacja. Zaznacza się również wpływ rozpuszczania na rozwój porowatości wtórnej. Przeprowadzone badania rzuciły nowe światło na charakter przestrzeni porowej oraz możliwości filtracyjne karpackich piaskowców o umiarkowanych porowatościach. O ile wartości przepuszczalności intergranularnych są w ogromnej większości niskie lub bardzo niskie, wykluczające w wielu przypadkach potencjalną produkcję z tego typu kolektorów o tyle zasięg i skala zeszczelinowania otwierają nowe możliwości interpretacji parametrów zbiornikowych i filtracyjnych tego typu utworów.On the base of 388 samples of the Carpathian sandstones analyses of intergranular and fracture permeability and porosity were performed, as well as granulometric analyses and investigations of diagenesis processes. Pore space of these sandstones was created by diagenetic processes. Mechanical compaction and cementation dominates but dissolution played role in creating of secondary porosity. Conducted investigations thrown a new light on filtration properties of moderate porosity sandstones. Intergranular permeability are very low but fracture porosity can reach relatively high values (up to 50 mD) in great part of investigated sandstones. This fact opens new opportunities in exploration of such type of sandstones in the Carpathian flysch
The determination of the specific heat capacity of coal based on literature data
W artykule omówiono wpływ właściwości węgla na jego pojemność cieplną właściwą. Przedstawiono literaturowe funkcje na określanie pojemności cieplnej właściwej węgla w zależności od temperatury i zawartości w nim części lotnych. Dla rozpatrywanych funkcji przeprowadzono obliczenia dla kilku węgli o znanych właściwościach, zestawiając otrzymane wyniki w formie zależności pojemność cieplna- temperatura. Przedstawiono wyniki analizy otrzymanych zależności oraz sugestie co do zakresu ich stosowalności.The article discusses the coal properties having influence on its specific heat capacity. The literature correlations for the determination the specific heat capacity of coal, depending on the temperature and the volatile matter content, are presented. To examine the correlation, calculations for several coals of known properties were made and obtained results are showed in the form of a specific heat – temperature diagram. The received results of the analysis of correlations and suggestions for its range of application are presented
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