Prophylaxis of infection in region of the surgical intervention performance in laparoscopic cholecystectomy

Objective. To estimate the efficacy of prophylactic method for regional infection while performance of laparoscopic cholecystectomy, using simultaneous application of container for removal of the specimen and a two-ring wound protector of the wound. In accordance to the literature data, the infection rate in laparoscopic cholecystectomy conduction constitutes 2.4 - 9.6%. Materials and methods. The work was based on experience of performance of 759 laparoscopic cholecystectomies during the period of 2015 - 2018 yrs. There were performed 679 operations with the second class of microbial contamination, 17 - with the third one and 6 - with the fourth. In 21 patients the conversion into laparotomy was applied. The patients with third and fourth classes of microbial contamination of wounds were divided into two groups: the first - 61 patients, in whom a container was used for the specimen removal, and the second - 19 patients, in whom the method of combined application of container and the wound protector was applied for removal of the specimen. Results. Infection of region of the surgical intervention performance in laparoscopic cholecystectomy was revealed in 41 (5.40%) of 759 patients.In surgical interventions In surgical interventions, referring to second class of microbial contamination , the infection rate in the surgical intervention region have constituted 2,5%, while referring to the third class - 11.76%, and the fourth class - 34.92%. Conversion in laparoscopic cholecystectomy is accompanied with high rate of the wound infection - 38.09%. Conclusion. Application of the method of combined usage of container for removal of preparation and a two-ring protector of the wound in the third and the fourth classes of the wounds while performance of laparoscopic cholecystectomy have permitted to lower the infection rate in region of the surgical intervention performance from 37.70 to 5.26%

The peculiarities of cross-correlation between two secondary precursors - radon and magnetic field variations, induced by stress transfer changes

A model of precursor manifestation mechanisms, stimulated by tectonic activity and some peculiarities of observer strategy, whose main task is the effective measurement of precursors in the spatial area of their occurrence on the Earth's daylight, are considered. In particular, the applicability of Dobrovolsky's approximation is analyzed, when an unperturbed medium (characterized by the simple shear state) and the area of tectonic activity (local inhomogeneity caused by the change only of shear modulus) are linearly elastic, and perturbation, in particular, surface displacement is calculated as a difference of the solutions of two independent static problems of the theory of elasticity with the same boundary condition on the surface. Within the framework of this approximation a formula for the spatial distribution (of first component) of magnetic field variations caused by piezomagnetic effect in the case of perturbed regular medium, which is in simple shear state is derived. Cogent arguments in favor of linear dependence between the radon spatial distribution and conditional deformation are obtained. Changes in magnetic field strength and radon concentrations were measured along a tectonomagnetic profile of the total length of 11 km in the surroundings of the "Academician Vernadsky" Station on the Antarctic Peninsula (W 64{\deg}16', S 65{\deg}15'). Results showed a positive correlation between the annual surface radon concentration and annual changes of magnetic field relative to a base point, and also the good coincidence with theoretical calculation.Comment: 27 pages, 11 figures, 3 tables (a substantially revised and extended edition; v3 -- some analysis of recent publications added

Study of the properties of self-sustaining nuclear chain reaction in the fuel-containing masses of the "Ukryttya" object for the case of varying velocity of water inflow

The main peculiarities of ignition and development of self-sustaining nuclear chain reaction (SCR) in fuel-containing masses (FCM) of Chernobyl "Ukryttya" were studied for the case of varying velocity of water incoming into the system or its outcoming. On the basis of analysis and numerical solution of the corresponding system of differential equations for the main characteristics of the system, it was shown that the variations of water inflow could lead to very sufficient and various changes in SCR development comparing to possible modes at constant velocities of water inflow. In particular, the calculations show that the neutron bursts with great amplitude could take place in the system under definite sufficiently reasonable physical conditions. It was also shown that the increase of velocity of water inflow into the FCM in the mode of constant oscillations can lead to transition into "beyond critical" state which is the subcritical state with big quantity of water

Study of ignition possibility, development and properties of self-sustaining nuclear chain reaction in the fuel-containing masses of the object “Ukryttya”

Main characteristic properties of ignition and development of self-sustaining nuclear chain reaction (SCR) in the fuel-containing masses (FCM) of the object “Ukryttya”, and also the main properties of SCR for a number of its typical essentially possible modes were studied. System of differential equations for the main physical quantities describing FCM was formulated. Numerical analysis and calculations according to this system show that the main possible modes of SCR are exponential growth of the neutron flux, mode of the solitary neutron flux burst of differing strength, and also mode of the neutron flux oscillations. Mode of the flux oscillations is of great interest and exhibits various properties. According to calculations, the neutron flux burst of extremely high strength appears to be possible under some likely and reasonable physical conditions in presence of the sufficient accumulation of fissile materials. But the most realistic and close to the experiment mode of SCR appears to be the mode of slow growth of the neutron flux progressively, as the system is flooded by water, and further subsequent transition into the mode of the neutron flux oscillations in the neighbourhood of the critical state

Radon in Antarctica

The paper reviews results of radon measurements obtained in Antarctic research stations in the last 40 years by both active and passive radon monitors. A brief description of the radon laboratory set-up in the Ukrainian Academician Vernadsky station on the Antarctic Peninsula (W 64°16′, S 65°15′), where radon is measured by two types of etched track Rn dosimeter and 4 types of continuous radon monitoring devices is presented. Some selected results of research work are described related to: (i) analysis of radon storms, defined as an abrupt increase of 222Rn during the occurrence of a cyclone, and its applicability for the study of the transport of air masses of continental origin to Antarctica; (ii) a study of the correlation of changes of radon concentration and geomagnetic field induced by tectonic activity and its application to predicting tectonomagnetic anomalies, and (iii) verification of a newly developed theoretical model based on noise analysis of the measured radon signal for earthquake prediction. Suggestions for future utilization of radon for basic research in Antarctica (and not only in Antarctica) conclude the contribution

Protective Effect of Germanium Citrate in Endotoxin-induced Ovarian Dysfunction in Mice.

Now it is known that endotoxin of gram-negative bacteria – lipopolysaccharide (LPS) is associated with disturbances of reproductive function in women. To simulate an ovarian dysfunction in endotoxemia and to explore a possible protective action of germanium (Ge) citrate obtained via nanotechnology we used LPS administration into female mice (3 mg/kg). Treatment with LPS caused patho­logical changes in mouse ovaries at 24h post-injection: an impairment of oocyte maturation in vitro, DNA damage in granulosa cells (as estimated by DNA-comet assay) and a decrease in their viability by increasing both necrosis and apoptosis. Pretreatment of mice with Ge citrate (i.p. 100 mkg/kg, 2 injections: 24 h and 1 h before LPS) was effective to reduce genotoxic stress and cell death. Ge citrate administration to LPS-treated mice significantly enhanced oocyte quality (as indicated by improvement in oocyte maturation) that may be due to cytoprotective effect of this compound on surrounding follicular cells. Our results support potential therapeutic application of Ge citrate to improve reproductive function in endotoxemia

The peculiarities of cross-correlation between two secondary precursors - radon and magnetic field variations, induced by tectonic activity

A model of precursor manifestation mechanisms, stimulated by tectonic activityand some peculiarities of observer strategy, whose main task is the effective measurement of precursors in the spatial area of their occurrence on the Earth\u27s daylight, are considered. In particular, the applicability of Dobrovolsky\u27s approximation is analyzed, when an unperturbed medium (characterized by the simple shear state) and the area of tectonic activity (local inhomogeneity caused by the change only of shear modulus) are linearly elastic, and perturbation, in particular, surface displacement is calculated as a difference of the solutions of two independent static problems of the theory of elasticity with the same boundary condition on the surface. Within the framework of this approximation a formula for the spatial distribution (offirst component) of magnetic field variations caused by piezomagnetic effect in the case of perturbed regular medium, which is in simple shear state is derived. Cogent arguments in favor of linear dependence between the radon spatial distribution and conditional deformation are obtained. Changes in magnetic field strength and radon concentrations were measured along a tectonomagnetic profile of the total length of 11 km in the surroundings of the "Academician Vernadsky" Station on the Antarctic Peninsula (W 64 16\u27, S 6515\u27). Results showed a positive correlation between the annual surface radonconcentration and annual changes of magnetic field relative to a base point, and also the good coincidence with theoretical calculation