34 research outputs found
The Evolution of Meson Masses in a Strong Magnetic Field
Spectra of hadrons are investigated in the framework of the
Hamiltonian obtained from the relativistic path integral in external
homogeneous magnetic field. The spectra of all 12 spin-isospin s-wave states,
generated by and mesons with different spin projections, are
studied both analytically and numerically on the lattice as functions of
(magnetic field) . Results are in agreement and demonstrate three types of
behavior, with characteristic splittings predicted by the theory.Comment: 29 pages, 7 figures, 1 tabl
Improving Methodological Approach to Measures Planning for Hydraulic Fracturing in Oil Fields
Goal of the research is development of an integrated approach to the planning of hydraulic fracturing (HF) treatment taking into account geo-technical, hydrodynamic, technological and economic criteria for the selection of wells for inclusion in the programs of HF with increasing importance of economic criteria.
Stages of formation of the program for HF of the oil company are selected, systematized and analyzed. It is shown that high potential effectiveness of enhanced oil recovery method in fields with hard-to-recover reserves, on the one hand, and the complexity and high cost of application, on the other, determine the need to optimize the parameters of this business process at all stages of implementation and improve its planning methods. The priority directions for improving the hydraulic fracturing planning were justified: a clear definition of the criterion for the payback period of hydraulic fracturing activities, taking into account their technological features, improving the procedure for calculating the costs of implementing this technology and improving the reasonableness of selecting candidate wells for inclusion in the hydraulic fracturing program.
Feasibility of using an additional criterion in the formation of hydraulic fracturing programs â marginal minimum cost-effective wall capacity â has been shown and a method for calculating it has been developed. The use of this criterion will allow to take into account not only technological limitations, but also limits of economic efficiency of conducting hydraulic fracturing at each specific well and, at the preliminary selection of candidate wells, exclude a priori unprofitable measures.
It is advisable to take into account proposed directions for improving planning of hydraulic fracturing in the development of corporate regulatory documents, which will help to improve the quality of planning geological and technical measures, minimize investment risks, make more rational use of oil companies' resources for improving oil recovery, choosing the best management decision
The System of Neutrophil Elastase and the Plasma Level of MMP-7 in Children with Pulmonary Arterial Hypertension and Chronic Cor Pulmonale
A significant increase in the activity of neutrophil elastase (NE) and anti-NE-protection in the plasma were detected in children having bronchopulmonary dysplasia (BPD) complicated by pulmonary arterial hypertension (PAH) and chronic cor pulmonale (CCP). The changes revealed were more pronounced in patients with CCP. The plasma concentration of the NE was slightly reduced, which was probably associated with the activation of anti-NE and an increase in the α1-antitrypsin level. A gradual increase was noted in the plasma level of the matrix metalloproteinase-7 (MMP-7) in patients with an increase in the severity of the condition. In patients with cystic fibrosis (with and without CCP), the pronounced increase in the MMP-7 level was observed. In patients with cystic fibrosis (CF), even without the additional complication with PAH and CCP, the MMP-7 level was significantly higher than in those with congenital broncho-pulmonary malformations (CBPM). The difference was increased in those patients with PAH and reached a maximum in those with CCP
Analysis of supply chain in investment activity in the Russian Agricultural complex
The article analyzes supply chain in investment attractiveness and capital supply chain in investments in the Russian agro-industrial complex. The authors analyze the current state of the Russian agro-industrial complex, study supply chain in investments in fixed assets in the agricultural sector, and identify the growth rates of the components of GDP productio
PSYCHOPHYSIOLOGIC AND IMMUNOLOGIC CHARACTERISTICS IN PATIENTS WITH BRONCHIAL ASTHMA AND IN HEALTHY MEN WITH DIFFERENT FUNCTIONAL ASYMMETRY OF THE HEMISPHERES OF THE BRAIN
On the basis of the analysis of own and literary data, proved the interaction psychophysiologic and immunologic parameters in healthy people and in patients with bronchial asthma. The main accent was made on the investigation of the role of the functional asymmetry of a brain, as the base phenomenon defining features of mental, vegetative and immunologic activity
Correlation between Antioxidant Enzymes Activity and Intraerythrocyte Concentration of Fe, Mg, Zn, Cu in Pulmonary Arterial Hypertension and Cor Pulmonale in Children with Congenital Lung Disease and Cystic Fibrosis
Significant changes in the levels of the potential prooxidant Cu (increase) and the antioxidant Zn (decrease) in plasma were revealed in children having bronchopulmonary dysplasia (BPD) complicated by pulmonary arterial hypertension (PAH) and chronic cor pulmonale (CCP) when compared with the control. The Zn / Cu ratio in the blood plasma of patients with BPD, especially in CCP, was found to be lower than in the control group (p<0.001). This could indicate the activation of the prooxidant processes; simultaneously, the total antioxidant status (AOS) decreased. No significant increase in the intracellular free (âionizedâ (i)) form of magnesium (iMg) was found; in fact, the concentration of iFe in all the patient groups was higher than in the control. An increase in the iCu and iZn levels (nonprotein-bound) was observed in the blood cells of the affected children. A significant increase in the glutathione peroxidase activity in the CCP patients may indicate an accumulation of organic peroxides, and partially compensate for the lesser activity of superoxide dismutase (SOD) and other antioxidants. The Zn / Cu and iZn/ iCu ratios were reduced in patients with CCP when compared with patients with PD without CCP
H2AX phosphorylation at the sites of DNA double-strand breaks in cultivated mammalian cells and tissues
A sequence variant of histone H2A called H2AX is one of the key components of chromatin involved in DNA damage response induced by different genotoxic stresses. Phosphorylated H2AX (ÎłH2AX) is rapidly concentrated in chromatin domains around DNA double-strand breaks (DSBs) after the action of ionizing radiation or chemical agents and at stalled replication forks during replication stress. ÎłH2AX foci could be easily detected in cell nuclei using immunofluorescence microscopy that allows to use ÎłH2AX as a quantitative marker of DSBs in various applications. H2AX is phosphorylated in situ by ATM, ATR, and DNA-PK kinases that have distinct roles in different pathways of DSB repair. The ÎłH2AX serves as a docking site for the accumulation of DNA repair proteins, and after rejoining of DSBs, it is released from chromatin. The molecular mechanism of ÎłH2AX dephosphorylation is not clear. It is complicated and requires the activity of different proteins including phosphatases and chromatin-remodeling complexes. In this review, we summarize recently published data concerning the mechanisms and kinetics of ÎłH2AX loss in normal cells and tissues as well as in those deficient in ATM, DNA-PK, and DSB repair proteins activity. The results of the latest scientific research of the low-dose irradiation phenomenon are presented including the bystander effect and the adaptive response estimated by ÎłH2AX detection in cells and tissues
Cohesin Protects Genes against ÎłH2AX Induced by DNA Double-Strand Breaks
Chromatin undergoes major remodeling around DNA double-strand breaks (DSB) to promote repair and DNA damage response (DDR) activation. We recently reported a high-resolution map of ÎłH2AX around multiple breaks on the human genome, using a new cell-based DSB inducible system. In an attempt to further characterize the chromatin landscape induced around DSBs, we now report the profile of SMC3, a subunit of the cohesin complex, previously characterized as required for repair by homologous recombination. We found that recruitment of cohesin is moderate and restricted to the immediate vicinity of DSBs in human cells. In addition, we show that cohesin controls ÎłH2AX distribution within domains. Indeed, as we reported previously for transcription, cohesin binding antagonizes ÎłH2AX spreading. Remarkably, depletion of cohesin leads to an increase of ÎłH2AX at cohesin-bound genes, associated with a decrease in their expression level after DSB induction. We propose that, in agreement with their function in chromosome architecture, cohesin could also help to isolate active genes from some chromatin remodelling and modifications such as the ones that occur when a DSB is detected on the genome