Possible toxicity of the aquatic environment of the cooling reservoir at the Zaporizhzhia Nuclear Power Plant (Ukraine) has been investigated to control and prevent pollution of its ecosystem in ...conditions of significant anthropogenic pressure. The biological test method was used to determine the chronic water toxicity of the cooling reservoir using Ceriodaphnia affinis Lilljeborg (Cladocera, Crustacea) as a test object. The criterion for chronic toxicity was a statistically significant decrease in survival and fertility of the Ceriodaphnia in the experiment compared to control over the three consecutive litters for 7 days. The reliability of the differences between the control and the experimant was determined by the methods of variation statistics. The prerequisite for studying ecotoxicity of the aquatic environment of the investigated water body was the increased copper and zinc content in water, which was established by preliminary studies of the hydrochemical regime of the reservoir. During the experimental period, no pathological changes in the experimental daphnia were detected. The obtained results allow to conclude that there was no toxic effect of the aquatic environment on the biota of the cooling reservoir and the possibility of using the method of biological amelioration can ensure the stabilization of its ecosystem. The research results can be used in the development and justification of methods for stabilizing the ecosystems of cooling reservoirs and managing bioproductivity for the purpose of their economic development.
The upgraded Large Hadron Collider beauty (LHCb) detector will provide data taken in Run3 at the instantaneous luminosity of proton-proton collisions increased to 2⋅1033 cm-2s-1 at energies of up to ...14 TeV. To ensure the safe operation of the experiment, a new beam and background Radiation Monitoring System (RMS-R3) was built. RMS-R3 is based on metal-foil detector technology developed at the Institute for Nuclear Research, National Academy of Sciences of Ukraine (Kyiv, Ukraine). The system comprises four detector modules with two sensors in each. Their frequency response is proportional to the flux of incident charged particles. The modules are located around the beam pipe at a distance of 2.2 m from the interaction point. The results measured during the Run3 in 2022 testify to the reliable operation of the system. Applying the asymmetry method, high-accuracy data were obtained on the localization of the interactions region and the beam and background contribution.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
For the feasibility studies of spatially fractionated hadron therapy prototypes of the equipment for hadron minibeams shaping and monitoring have been designed, built and tested. The collimators ...design was based on Monte Carlo simulations (Gate v.6.2). Slit and matrix collimators were used for minibeams shaping. Gafchromic films, micropixel detectors Timepix in a hybrid as well as metal mode were tested for measuring hadrons intensity distribution in minibeams. An overall beam profile was measured by the metal microstrip detector. The performance of a mini-beams shaping and monitoring equipment was characterized exploring low energy protons at the KINR Tandem generator as well as high energy carbon and oxygen ion beams at HIT (Heidelberg). The results demonstrate reliable performance of the tested equipment for shaping and imaging hadron mini-beam structures.
The ZnS:Mn, Mg powder is fabricated by self-propagating high-temperature synthesis with the simultaneous introduction of Mn and Mg impurities. It is found that the simultaneous introduction of Mn and ...Mg impurities leads to the nonuniform distribution of manganese forming regions with a lower and higher Mn concentration. In the latter case, the manganese ions form paramagnetic clusters. At the same time, numerous centers of self-activated luminescence form in the synthesized ZnS:Mn, Mg due to mechanical stress and lattice strain. Additional annealing leads to a more uniform Mn distribution in the formed ZnS:Mn, Mg phosphor, which is accompanied by an increase in the intensity of the manganese photoluminescence band and quenching of the self-activated luminescence band.
Introduction. The key feature of the economy development in the 21st century is digitalization – the transition to a digital economy. Digital is considered an economy based on digital computer ...technology (also called the Internet economy, new economy, or web economy). The rapid proliferation of digital technologies accelerates the pace of development of international economic relations: increasing of competition in national and international markets, liberalization of economic policies of states, especially in developed countries. Purpose. The purpose of the research is to analyze main trends of e-business development and what impact does e-business have on national economies and world economy in general. Results. The article deals with the main trends of the influence that the development of e-business on the world economy has. Thus, the United States and China have been and remain leaders among the countries in terms of the capacity of the e-commerce market, however, India and the countries of Latin America are actively involved in this trend. The rapid development of e-business is gaining in the poorly developed countries where in recent years there has been a tendency to increase the share of the population with access to the Internet. It should be noted that the positive results from the development of e-business for national economies have both quantitative (value) and qualitative character, in particular, new technologies considerably facilitate business procedures, which is confirmed by the increase of the place in the Doing Business rating for countries where e-commerce is developing at a fast pace. Conclusions. The development of e-business accelerates economic growth, so new players are rapidly selecting a part of the market from countries that have exhausted their potential for rapid growth (Latin America vs. Europe). E-business influences all spheres of economic relations and one of its key advantages is simplification of business (as evidenced by examples of countries such as the US, China, and India). Thus, in the era of the digital economy, the development of electronic business has evolved from an opportunity into a necessity – the necessity of constant development in order to remain competitive in the world economic arena.
Fine ZnS:Cu, obtained by method of self-propagating high-temperature synthesis was investigated. As flux in the mixture NaCl was used, Zn and S were taken in stoichiometric ratio; Cu concentration in ...charge consisted ~1.5 wt.%. Using SEM data, it was established that obtained ZnS:Cu consists from two fractions—first with particles sizes ~10 μm and more, and other with sizes 50–500 nm. It was established that composition of ZnS:Cu fractions was essentially different. According to EDS data, Cu concentration in particles of fraction with 50–500 nm sizes consists ~2 wt.%, and in particles with sizes ~10 μm and more the presence of Cu was not detected. The reasons that lead to the selective doping of particles in dependence on their size and also the role of NaCl in processes undergoing during synthesis of material are discussed.
From year to year, wide spread of gastroesophageal reflux disease (GERD) is attracting greater attention of specialists in the field of this pathology diagnosis and treatment. In-depth studies on ...etiological and pathogenetic factors in the GERD development are being conducted. Of particular interest is the role of humoral factors, one of which is vasoactive intestinal peptide (VIP). There are currently no data on the dynamics of this hormone during surgical treatment of GERD.
The aim of the study was to examine the dynamics of plasma VIP during surgical treatment of GERD and its influence on the lower esophageal sphincter (LES) function.
Materials and methods. Surgical treatment in the Nissen modification was performed for 35 patients with GERD. There were 26 women (74.3 %), men – 9 (25.7 %). mean age – 55.3 ± 11.3 years. Comparison group – 20 apparently healthy individuals: women – 14 (70.0 %); men – 6 (30.0 %), mean age – 56.7 ± 10.6 years. VIP was measured in venous blood plasma by an enzyme immunoassay (Vasoactive intestinal peptide ELISA, S-1201, BCM Diagnostics) using an immunoenzyme complex ImmunoChem-2100 (USA). The sampling of the studied samples in the main group was carried out before the operation and 2–3 months post-surgery.
Results. In the main group before the surgery, the level of VIP was 3.1 ± 1.1 ng/ml, after the surgery – 2.2 ± 1.0 ng/ml. In the comparison group, VIP was determined at the level of 2.1 ± 1.1 ng/ml. In GERD before the surgery, the VIP level was statistically different from the indicators in the comparison group and from postoperative values. After surgical treatment, VIP values were decreased to the level of apparently healthy individuals. There was a positive correlation between the VIP level and acid exposure time (AET), the total number of refluxes, the number of reflux events longer than 5 minutes, the maximum duration of refluxes and the degree of esophageal inflammation.
Conclusions. In the surgical treatment of GERD, the statistically significant decrease in the VIP level to that of apparently healthy individuals is determined. The moderate positive correlation between the levels of VIP, AET, the average number of refluxes, the number of reflux events longer than 5 minutes, and the maximum duration of refluxes confirms the inhibitory effect of VIP on LES tone. The relationship between the degree of esophageal inflammation and the VIP level confirms the indirect, through the action of VIP, inhibitory effect of the esophagitis severity on the LES tone.
Characterization studies of the metal micro-detector TimePix measuring dose distribution at the Minibeam Radiation Therapy setup (Bio-Medical Beamline ID17, ESRF) were performed. The results obtained ...for high intensity synchrotron radiation minibeams illustrate an excellent performance of the TimePix providing in real time 2D image of the dose distribution over many beams in a 14×14mm2 area. Peak-to-Valley–Dose–Ratios measured by TimePix and gafhromic films agree well.
Design of collimators and their effectiveness for the purposes of the fractionated mini-beam hadron radiation therapy were evaluated by Monte Carlo simulations. The calculations have been performed ...for proton, carbon and oxygen ion beams at the energies relevant for medical applications. Micropixel metal and hybrid detectors were tested for measuring charged particles intensity distribution in multi-beam structures shaped by slit or matrix collimators exploring low energy proton beam at the Tandem generator (INR NASU, Kyiv). The results obtained illustrate reliable performance of the designed collimators as well as hybrid and metal microdetectors for measuring and imaging in real time the proton intensity distribution over mini-beam structures.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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