314 research outputs found
On the Rational Type 0f Moment Angle Complexes
In this note it is shown that the moment angle complexes Z(K;(D^2,,S^1))
which are rationally elliptic are a product of odd spheres and a diskComment: This version avoids the use of an incorrect result from the
literature in the proof of Theorem 1.3. There is some text overlap with
arXiv:1410.645
Using Strategy Improvement to Stay Alive
We design a novel algorithm for solving Mean-Payoff Games (MPGs). Besides
solving an MPG in the usual sense, our algorithm computes more information
about the game, information that is important with respect to applications. The
weights of the edges of an MPG can be thought of as a gained/consumed energy --
depending on the sign. For each vertex, our algorithm computes the minimum
amount of initial energy that is sufficient for player Max to ensure that in a
play starting from the vertex, the energy level never goes below zero. Our
algorithm is not the first algorithm that computes the minimum sufficient
initial energies, but according to our experimental study it is the fastest
algorithm that computes them. The reason is that it utilizes the strategy
improvement technique which is very efficient in practice
Genetic markers of Munc13 protein family member, BAIAP3, are gender-specifically associated with anxiety and benzodiazepine abuse in mouse and man
Anxiety disorders and substance abuse, including benzodiazepine use disorder, frequently occur together. Unfortunately, treatment of anxiety disorders still includes benzodiazepines, and patients with an existing comorbid benzodiazepine use disorder or a genetic susceptibility for benzodiazepine use disorder may be at risk of adverse treatment outcomes. The identification of genetic predictors for anxiety disorders, and especially for benzodiazepine use disorder, could aid the selection of the best treatment option and improve clinical outcomes. The brain-specific angiogenesis inhibitor I–associated protein 3 (Baiap3) is a member of the mammalian uncoordinated 13 (Munc13) protein family of synaptic regulators of neurotransmitter exocytosis, with a striking expression pattern in amygdalae, hypothalamus and periaqueductal gray. Deletion of Baiap3 in mice leads to enhanced seizure propensity and increased anxiety, with the latter being more pronounced in female than in male animals. We hypothesized that genetic variation in human BAIAP3 may also be associated with anxiety. By using a phenotype-based genetic association study, we identified two human BAIAP3 single-nucleotide polymorphism risk genotypes (AA for rs2235632, TT for rs1132358) that show a significant association with anxiety in women and, surprisingly, with benzodiazepine abuse in men. Returning to mice, we found that male, but not female, Baiap3 knockout (KO) mice develop tolerance to diazepam more quickly than control animals. Analysis of cultured Baiap3 KO hypothalamus slices revealed an increase in basal network activity and an altered response to diazepam withdrawal. Thus, Baiap3/BAIAP3 is gender specifically associated with anxiety and benzodiazepine use disorder, and the analysis of Baiap3/BAIAP3-related functions may help elucidate mechanisms underlying the development of both disorders
INFLUENCE EXERTED BY SOMATIC PATHOLOGY ON RISKS OF OCCUPATIONAL LUNG FIBROSIS IN WORKERS EMPLOYED AT REFRACTORY PRODUCTION
Occupational lungs and bronchial pathology occurs not only under exposure to dusts, their aerosol structure and aggression, but also depends on individual properties of a body. The latter can determine either increased body resistance or susceptibility to occupational pathology occurrence. Our research goal was to determine influence exerted by somatic pathology on occupational lung fibrosis occurrence as well as to estimate prevalence of risk factors for cardiovascular and metabolic pathology occurrence in workers employed at refractory production. At the first stage 449 workers employed at refractory production were examined at a periodical medical examination (PME). Patients' average age was 41.59 ± 0.45 and average work experience was 14.47 ± 0.39 years. At the second stage 172 workers were examined at an occupational pathology center; 75 out of them were workers who had silicosis and were included into the test group and the remaining 97 workers didn't have any occupational pathology and were included into the reference group. Both groups were comparable as per sex (p = 0.0052) and work experience under exposure to dusts (p = 0.862). Workers examined at a PME most frequently had overweight and obesity (68 %). Arterial hypertension (AH) prevalence amounted to 19.5%; carbohydrate metabolism disorders, 19.8 %; 48.1 % workers had hypercholesterolemia. Patients with silicosis had certain disorders significantly more frequently than workers with long work experience but without any occupational pathologies; those disorders were AH, cardiac muscle hypertrophy in the left ventricle, ischemic heart disease, heart rate disorders, as well as mixed (obstructive and restrictive) breath mechanics disorders. We determined some factors that authentically produced certain effects on occupational lung fibrosis occurrence in workers employed at refractory production. Median time of silicosis occurrence was significantly shorter (by 11.5 years) among workers with severe AH, arrhythmia (by 13 years), lower hemoglobin in blood (by 11.5 years). Besides, silicosis occurred significantly earlier (by 10.8) among women than among men. © 2020 Obukhova T.Yu., Budkar' L.N., Gurvich V.B., Solodushkin S.I., Shmonina O.G., Karpova E.A.,. All Rights Reserved
Manifestation of systemic toxicity in rats after a short-time inhalation of lead oxide nanoparticles
Outbred female rats were exposed to inhalation of lead oxide nanoparticle aerosol produced right then and there at a concentration of 1.30 ± 0.10 mg/m3 during 5 days for 4 h a day in a nose-only setup. A control group of rats were sham-exposed in parallel under similar conditions. Even this short-time exposure of a relatively low level was associated with nanoparticles retention demonstrable by transmission electron microscopy in the lungs and the olfactory brain. Some impairments were found in the organism’s status in the exposed group, some of which might be considered lead-specific toxicological outcomes (in particular, increase in reticulocytes proportion, in δ-aminolevulinic acid (δ-ALA) urine excretion, and the arterial hypertension’s development). © 2020 by the authors. Licensee MDPI, Basel, Switzerland.Funding: This work was funded by the budget of the Ekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers
Toxic effects of low-level long-term inhalation exposures of rats to nickel oxide nanoparticles
Rats were exposed to nickel oxide nanoparticles (NiO-NP) inhalation at 0.23 ± 0.01 mg/m3 for 4 h a day 5 times a week for up to 10 months. The rat organism responded to this impact with changes in cytological and some biochemical characteristics of the bronchoalveolar lavage fluid along with a paradoxically little pronounced pulmonary pathology associated with a rather low chronic retention of nanoparticles in the lungs. There were various manifestations of systemic toxicity, including damage to the liver and kidneys; a likely allergic syndrome as indicated by some cytological signs; transient stimulation of erythropoiesis; and penetration of nickel into the brain from the nasal mucous membrane along the olfactory pathway. Against a picture of mild to moderate chronic toxicity of nickel, its in vivo genotoxic effect assessed by the degree of DNA fragmentation in nucleated blood cells (the RAPD test) was pronounced, tending to increasing with the length of the exposure period. When rats were given orally, in parallel with the toxic exposure, a set of innocuous substances with differing mechanisms of expected bioprotective action, the genotoxic effect of NiO-NPs was found to be substantially attenuated. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.For modeling chronic intoxication development under low-level but long-term inhalation exposures to NiO nanoparticles, the experiments were carried out on outbred white female rats from our own breeding colony with an initial body weight of 150–220 g, with a minimum of 12 animals in exposed and control groups. Rats were housed in conventional conditions, breathed unfiltered air, and were fed standard balanced food. The experiments were planned and implemented in accordance with the “International guiding principles for biomedical research involving animals” developed by the Council for International Organizations of Medical Sciences (1985) and were approved by the Ethics Committee of the Ekaterinburg Medical Research Center Medical for Prophylaxis and Health Protection in Industrial Workers
New Insights into the mineralogy of the Atlantis II deep metalliferous sediments, Red Sea
The Atlantis II Deep of the Red Sea hosts the largest known hydrothermal ore deposit on the ocean floor and the only modern analog of brine pool-type metal deposition. The deposit consists mainly of chemical-clastic sediments with input from basin-scale hydrothermal and detrital sources. A characteristic feature is the millimeter-scale layering of the sediments, which bears a strong resemblance to banded iron formation (BIF). Quantitative assessment of the mineralogy based on relogging of archived cores, detailed petrography, and sequential leaching experiments shows that Fe-(oxy)hydroxides, hydrothermal carbonates, sulfides, and authigenic clays are the main “ore” minerals. Mn-oxides were mainly deposited when the brine pool was more oxidized than it is today, but detailed logging shows that Fe-deposition and Mn-deposition also alternated at the scale of individual laminae, reflecting short-term fluctuations in the Lower Brine. Previous studies underestimated the importance of nonsulfide metal-bearing components, which formed by metal adsorption onto poorly crystalline Si-Fe-OOH particles. During diagenesis, the crystallinity of all phases increased, and the fine layering of the sediment was enhanced. Within a few meters of burial (corresponding to a few thousand years of deposition), biogenic (Ca)-carbonate was dissolved, manganosiderite formed, and metals originally in poorly crystalline phases or in pore water were incorporated into diagenetic sulfides, clays, and Fe-oxides. Permeable layers with abundant radiolarian tests were the focus for late-stage hydrothermal alteration and replacement, including deposition of amorphous silica and enrichment in elements such as Ba and Au
Electron microscopy study on the transport of lead oxide nanoparticles into brain structures following their subchronic intranasal administration in rats
White outbred female rats were exposed intranasally to 50-µL of suspension of lead oxide nanoparticles (PbO NPs) at a concentration of 0.5 mg/mL thrice a week during six weeks. A control group of rats was administered deionized water in similar volumes and conditions. The developed intoxication was manifested by altered biochemical and cytochemical parameters, as well as behavioral reactions of animals. Using electron microscopy and energy-dispersive X-ray spectroscopy techniques, we revealed deposition of PbO NPs in the olfactory bulb, but not in basal ganglia, and an increase in the number of axons with damage to the myelin sheath in the tissues of olfactory bulb and basal ganglia, changes in the ultrastructure of mitochondria of neurons in the tissues of olfactory bulb and basal ganglia of the brain, and differences in the mitochondrial profile of neurons in different regions of the rat brain. Our results collectively suggest that the central nervous system may be a target of low-level toxicity of lead oxide nanoparticles. © 2022, The Author(s).Ural Federal University Program of DevelopmentYekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial WorkersMinistry of Education and Science of the Russian Federation, MinobrnaukaThe research funding from Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers for funding the experimental materials and facilities is gratefully acknowledged. The research funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority–2030 Program) for experiment implementation and analysis of its results is gratefully acknowledged
Comparative and Combined In Vitro Vasotoxicity of Nanoparticles Containing Lead and Cadmium
In vitro toxicological experiments were performed on an endothelial cell line exposed to different doses of spherical nanoparticles of cadmium and/or of lead sulfides with mean diameter 37 ± 5 nm and 24 ± 4 nm, respectively. Toxic effects were estimated by Luminescent Cell Viability Assay, endothelin-1 concentration and cell size determination. Some dose-response relationships were typically monotonic (well approximated with hyperbolic function) while others were bi- or even 3-phasic and could be described within the expanded hormesis paradigm. The combined toxicity type variated depending on the effect it was assessed by. © The Author(s) 2021
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