The Modeling of the Fan-Cooler Systems of the Containment VVER 440 V213 NPP

Doktorská dizertačná práca sa zaoberá problematikou zostavenia modelu existujúcich ventilačných systémov jadrového bloku VVER440/V213 v režimoch pokrývajúcich nie len oblasť normálnej prevádzky bloku na výkone, ale aj abnormálnej prevádzky a havarijných stavov bloku, ktoré sa významne odlišujú od návrhových podmienok týchto systémov. Práca sa zaoberá zostavením a popisom pokročilého modelu, ktorý je schopný predikovať správanie sa týchto systémov pri ich prípadnej prevádzke počas havarijných režimov bloku. Predstavený model je súčasťou širšieho modelu LEAKBOX, ktorý sa zaoberá modelovaním procesov v hermetickej zóne jadrového bloku VVER 440 počas havarijných režimov spojených s malým únikom chladiva.The topic of the thesis regards of problems of compilation the model of existing fan-cooler systems of VVER440/V213 NPP. These systems can be operated not only normal operation conditions but also during abnormal and accidental operation of the plant, which are significantly different from those operating conditions for which were systems dedicated and designed. An advanced model, compiled as one of the subjects of this thesis, capable to predict behaviour of these systems during accidental conditions of the plant, is described within this paper. The advanced model is a part of LEAKBOX model. LEAKBOX model represents a superordinated program dedicated to modelling overall VVER 440/V213 containment response during accidental conditions of the plant focusing onto small coolant leakage in to the containment.

Results of the winter waterbird census in Slovakia in 2019–2022

A total of 75 (59–69 annually) waterbird species with 129 541–166 543 ( =146 567) individuals were recorded during the January censuses in 2019–2022 in Slovakia. There were found no significant differences in species richness between the years. The most abundant species were Anas platyrhynchos (44.5–53.9% of all registered birds), Anser albifrons (6.8–17.7%) and Aythya fuligula (8.8–10.8%). A. platyrhynchos and A. fuligula were also the species with the lowest interannual variability in the number of individuals recorded. On the other hand, Calidris alpina, C. minuta, Cygnus columbianus, Hydrocoloeus minutus and Numenius arquata were registered only in one year, and C. minuta and C. columbianus were recorded for the first time in Slovakia in January. The overall wintering waterbird assemblage can be considered stable in terms of bird numbers in 2019–2022. However, several species (Aix galericulata, A. sponsa, Alopochen aegyptiaca, Mareca penelope and M. strepera) showed an increase in wintering individuals

The Proposal of Structure for Workplaces with Palletizing Robot

Abstract The article describes design of structure palletizing robot workplace. There is described a composition of work and criteria for selection of palletizing robot. End of the article are shown the typical structure of the palletizing workstations

Metabolomic analysis reveals changes in plasma metabolites in response to acute cold stress and their relationships to metabolic health in cold-acclimatized humans

Cold exposure results in activation of metabolic processes required for fueling thermogenesis, potentially promoting improved metabolic health. However, the metabolic complexity underlying this process is not completely understood. We aimed to analyze changes in plasma metabolites related to acute cold exposure and their relationship to cold-acclimatization level and metabolic health in cold-acclimatized humans. Blood samples were obtained before and acutely after 10–15 min of ice-water swimming (<5 °C) from 14 ice-water swimmers. Using mass spectrometry, 973 plasma metabolites were measured. Ice-water swimming induced acute changes in 70 metabolites. Pathways related to amino acid metabolism were the most cold-affected and cold-induced changes in several amino acids correlated with cold-acclimatization level and/or metabolic health markers, including atherogenic lipid profile or insulin resistance. Metabolites correlating with cold-acclimatization level were enriched in the linoleic/α-linolenic acid metabolic pathway. N-lactoyl-tryptophan correlated with both cold-acclimatization level and cold-induced changes in thyroid and parathyroid hormones. Acute cold stress in cold-acclimatized humans induces changes in plasma metabolome that involve amino acids metabolism, while the linoleic and α-linolenic acid metabolism pathway seems to be affected by regular cold exposure. Metabolites related to metabolic health, thermogenic hormonal regulators and acclimatization level might represent prospective molecular factors important in metabolic adaptations to regular cold exposure.ISSN:2218-198

An In Vitro Corrosion Study of Open Cell Iron Structures with PEG Coating for Bone Replacement Applications

Iron-based substrates with polyethylene glycol coating were prepared as possible materials for biodegradable orthopedic implants. Biodegradable materials that provide mechanical support of the diseased tissue at the time of implanting and then disappear gradually during the healing process are sometimes favored instead of permanent implants. The implant degradation rate should match the time of the tissue regrowth. In this work, the degradation behavior of iron-based foams was studied electrochemically during immersion tests in Hanks’ solution. The corrosion rate of the polyethylene glycol-coated samples increased and the corrosion potential shifted to more negative values. This indicates an enhanced degradation rate as compared to the uncoated material, fulfilling the goal of being able to tune the degradation rate. It is the interfacial interaction between the hydrophilic polymer layer and the iron surface that is responsible for the enhanced oxidation rate of iron

Cold Exposure Distinctively Modulates Parathyroid and Thyroid Hormones in Cold-Acclimatized and Non-Acclimatized Humans

Cold-induced activation of thermogenesis modulates energy metabolism, but the role of humoral mediators is not completely understood. We aimed to investigate the role of parathyroid and thyroid hormones in acute and adaptive response to cold in humans. Examinations were performed before/after 15 minutes of ice-water swimming (n = 15) or 120 to 150 minutes of cold-induced nonshivering thermogenesis (NST) applied to cold-acclimatized (n = 6) or non-acclimatized (n = 11) individuals. Deep-neck brown adipose tissue (BAT) was collected from non-acclimatized patients undergoing elective neck surgery (n = 36). Seasonal variations in metabolic/hormonal parameters of ice-water swimmers were evaluated. We found that in ice-water swimmers, PTH and TSH increased and free T3, T4 decreased after a 15-minute winter swim, whereas NST-inducing cold exposure failed to regulate PTH and free T4 and lowered TSH and free T3. Ice-water swimming-induced increase in PTH correlated negatively with systemic calcium and positively with phosphorus. In non-acclimatized men, NST-inducing cold decreased PTH and TSH. Positive correlation between systemic levels of PTH and whole-body metabolic preference for lipids as well as BAT volume was found across the 2 populations. Moreover, NST-cooling protocol-induced changes in metabolic preference for lipids correlated positively with changes in PTH. Finally, variability in circulating PTH correlated positively with UCP1/UCP1, PPARGC1A, and DIO2 in BAT from neck surgery patients. Our data suggest that regulation of PTH and thyroid hormones during cold exposure in humans varies by cold acclimatization level and/or cold stimulus intensity. Possible role of PTH in NST is indicated by its positive relationships with whole-body metabolic preference for lipids, BAT volume, and UCP1 content