Estimation of the Operating Parameters of Miniature Radioisotope Thermoelectric Power Unit Based on the Th-228 Isotope

The article considers the construction of a miniature radioisotope power unit based on thermoelectric conversion of thermal energy released during nuclear decay. It is proposed to use thin fluoropolymer films (membranes) as a dielectric heat-insulating material. The results of numerical simulation of a prototype of a miniature radioisotope thermoelectric battery unit based on the thorium-228 isotope in the ANSYS program are presented. The geometry of the system has been optimized. It was established that the temperature of the source can reach about 1033 K, and the efficiency of the considered battery unit can reach 16.8%, which corresponds to modern power supplies of this type

Microbiological monitoring of a multidisciplinary medical organization: the basis of strategic planning in the framework of the implementation of epidemiological safety

Relevance. Monitoring of antibiotic resistance and the frequency of isolation of microorganisms at the regional level in each medical organization is of paramount importance for the implementation of epidemiological safety. Objective.  To identify the main microbiological trends based on the analysis of the microflora of patients in a single — profile hospital in order to implement weaknesses in strategic planning activities.  Materials and methods. A comprehensive analysis of the pharmacoepidemiological results of the consumption of antimicrobial drugs with calculated drug resistance indices and microbiological monitoring data demonstrated the presence of weaknesses and strengths for the strategic development of a multidisciplinary hospital at the regional level in terms of epidemiological safety.  Results . Statistically significant differences in the microbiological structure of pathogens are predetermined by the profile of medical care. The main trends in the change in the microflora of a multidisciplinary hospital as a whole are the prevalence of fungal and gram-negative pathogens over gram-positive ones. The presence of a relatively high index of consumpion of cephalosporins of 3–4 generations, fluoroquinolones, carbapenems, protected penicillins determines the high drug resistance index of Klebsiella pneumoniae (0.86) and characterizes the main microbiological trends of a multidisciplinary clinic.  Conclusion. Risk stratification by the level of multidrug-resistant pathogens, the use of deterrent strategies for prescribing antimicrobials, the implementation of educational modules, the evaluation of the effectiveness and monitoring of the risk stratification program with in the framework of antimicrobial technologies, the analysis of microbial landscape data using decision support programs are the main tasks of the functioning of a multidisciplinary team of specialists in a multidisciplinary clinic to control antibiotic resistance

Морфофункциональные изменения в структуре зон коры надпочечников крыс под влиянием алкогольной интоксикации и антиоксиданта

Burdenko State Medical Academy of Voronezh, Voronezh, Russia, Conferinţa Știinţifică Internaţională ”Probleme actuale ale morfologiei” dedicată сentenarului profesorului B.Z. Perlin, Chişinău, 20-22 septembrie 2012Studies have shown that prolonged involuntary alcohol intoxication causes significant structural and functional reorganization of the cortex of the adrenal glands. Natural antioxidant α-tocopherol has a modifying influence on changes in the cells of the adrenal glands cortex in case of alcoholization, with the intensity and direction of this effect depends on whether the use of alcohol is being continued. Исследования показали, что длительная непроизвольная алкогольная интоксикация приводит к значительной структурной и функциональной реорганизации коры надпочечников. Природный антиоксидант α-токоферол имеет модифицирующее влияние на изменения в клетках коры надпочечников железы в случае алкоголизации, интенсивность и направленность этого влияния зависит от того, продолжается ли употребление алкоголя

DFT study of dihydrogen addition to molybdenum π-heteroaromatic complexes: a prerequisite step for the catalytic hydrodenitrogenation process

International audienceThe range of molybdenum hydride complexes that are sought to participate in the important catalytic hydrodenitrogenation process (HDN) of nitrogen containing polycyclic aromatic hydrocarbons were evaluated by DFT studies. The previously synthesized stable (η6-quinoline)Mo(PMe3)3 complex 1N, in which molybdenum is bonded to the heterocyclic ring, was chosen as a model. The hydrogenation of the quinone heterocycle, which was postulated as the initial step in the overall HDN reaction, is found to occur via three consecutive steps of the oxidative addition of dihydrogen to Mo in 1N. Successive transfer of hydrogen atoms from the metal to the heterocycle leads to the ultimate formation of the tetrahydrido molybdenum intermediate Mo(PMe3)4H413 and 2,2,3,3-tetrahydroquinoline C9H11N 14. All the involved intermediates and transition states have been fully characterized by DFT. This computational modeling of the hydrogenation of quinoline, as a part of extended HDN catalytic processes, provides a fundamental understanding of such mechanism

Photonuclear Reactions of Three-Nucleon Systems

We discuss the available data for the differential and the total cross section for the photodisintegration of $^3$He and $^3$H and the corresponding inverse reactions below $E_\gamma = 100$ MeV by comparing with our calculations using realistic $NN$ interactions. The theoretical results agree within the errorbars with the data for the total cross sections. Excellent agreement is achieved for the angular distribution in case of $^3$He, whereas for $^3$H a discrepancy between theory and experiment is found.Comment: 11 pages (twocolumn), 12 postscript figures included, uses psfig, RevTe

Femtometer Toroidal Structures in Nuclei

The two-nucleon density distributions in states with isospin $T=0$, spin $S$=1 and projection $M_S$=0 and $\pm$1 are studied in $^2$H, $^{3,4}$He, $^{6,7}$Li and $^{16}$O. The equidensity surfaces for $M_S$=0 distributions are found to be toroidal in shape, while those of $M_S$=$\pm$1 have dumbbell shapes at large density. The dumbbell shapes are generated by rotating tori. The toroidal shapes indicate that the tensor correlations have near maximal strength at $r<2$ fm in all these nuclei. They provide new insights and simple explanations of the structure and electromagnetic form factors of the deuteron, the quasi-deuteron model, and the $dp$, $dd$ and $\alpha d$ $L$=2 ($D$-wave) components in $^3$He, $^4$He and $^6$Li. The toroidal distribution has a maximum-density diameter of $\sim$1 fm and a half-maximum density thickness of $\sim$0.9 fm. Many realistic models of nuclear forces predict these values, which are supported by the observed electromagnetic form factors of the deuteron, and also predicted by classical Skyrme effective Lagrangians, related to QCD in the limit of infinite colors. Due to the rather small size of this structure, it could have a revealing relation to certain aspects of QCD.Comment: 35 pages in REVTeX, 25 PostScript figure

First Results on 12Lambda-C production at DAPHNE

Lambda-hypernuclei are produced and studied, with the FINUDA spectrometer, for the first time at an e+e- collider: DAPHNE, the Frascati phi-factory. The slow negative kaons from phi(1020) decay are stopped in thin (0.2 g/cm^2) nuclear targets, and Lambda-hypernuclei formation is detected by measuring the momentum of the outgoing pi^-. A preliminary analysis on 12Lambda-C shows an energy resolution of 1.29 MeV FWHM on the hypernuclear levels, the best obtained so far with magnetic spectrometers at hadron facilities. Capture rates for the ground state and the excited ones are reported, and compared with previous experiments.Comment: 15 pages, 5 figures. v2: one reference updated. Accepted for publication in Phys. Lett.

Nuclear astrophysics with radioactive ions at FAIR

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes