14 research outputs found

    A Tailing Dump as Industrial Deposit; Study of the Mineralogical Composition of Tailing Dump of the Southern Urals and the Possibility of Tailings Re-Development

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    It is found that regions with depleted, or on the verge of depletion, of mineral resources are subject to additional pressures due to intensifying social and environmental problems. This paper proposes the development of the mining industry, reducing the dependence of the economy on the sharp volatility of the raw materials market in a period of global shocks by addressing social and environmental problems in regions with a depleting mineral resource base. It is assumed that the geotechnology development from simple mineral extraction to technologies providing a full cycle of georesources development with industrial waste recycling contributes to the resource provision of sustainable development. The material and mineralogical composition of the four tailing dumps (Uchalinskiy, Buribayskiy, Sibayskiy and Gaiskiy Ore-Processing plants have been studied) united with the similarity of the processed raw materials, and as a consequence, the similar enrichment technology has been studied and established. An approximate estimate of valuable components left in industrial wastes was made. The possibility of valuable component extraction (e.g., gold) from tailings using double agitation cyanidation was substantiated. There is no necessity of obligatory grinding of tailings to increase the recovery rate of valuable components. It was experimentally determined that the extraction of gold from tailings is 75.9–82.14% and depends on the investigated technogenic raw material. It has been proved that industrial waste can be recycled for the purpose of the resource provision of sustainable development. The need for further, more detailed studies of industrial formations has been identified. This will help to identify patterns of valuable component distribution in the industrial mass and to study its extraction possibilities in more details

    Catheter ablation for atrial fibrillation after an unsuccessful surgical ablation and biological prosthetic mitral valve replacement: A pilot study

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    Background: Patients with mitral valve (MV) disease and atrial fibrillation (AF) undergo simultaneous prosthetic valve replacement and radiofrequency (RF) ablation procedure; however, this combinational procedure restores sinus rhythm (SR) in only 68–82% of the cases. In patients with ineffective surgical ablation, the use of a biological prosthetic valve might not only be a good choice to perform safe catheter ablation procedure in the left atrium (LA), but also provide a way to discontinue administration of oral anticoagulants. The objective of this study was to assess the efficacy of catheter ablation for AF after MV replacement with a biological prosthesis and an ineffective surgical ablation procedure. Methods: Ten consecutive patients aged 48 ± 7 years were enrolled in this study. All patients had long-persistent AF associated with a rheumatic valve disease, which was treated by MV replacement with a biological prosthesis and a surgical RF ablation procedure. In the late postoperative period, all the patients had recurrent hemodynamically significant AF, which required repeated cardioversions. From 1 year to 3 years after the surgery, catheter ablation was performed, including reisolation of pulmonary veins (PVs) with the ablation of ganglionic plexi or linear lesions on the roof of the LA and mitral isthmus. The efficacy was assessed at 3 months, 6 months, and 12 months after the procedure. Results: Restoration of SR during ablation was achieved in all of the cases. In 6–9 months, all the patients were free of arrhythmia. LA stunning manifested by the absence or decrease of the “A” wave in the transmitral flow and the retrograde wave in the PV flow was observed in nine patients with SR. In five of the patients, LA contractile function was restored in 1–6 months. Prosthetic valve dysfunction was not detected in any of the patients. Conclusion: Catheter ablation is an effective method for AF treatment following an ineffective surgical RF ablation procedure and biological prosthetic MV replacement. The use of bioprosthetic MVs allows for performing safe catheter ablation without subsequent prosthetic dysfunction

    Silicon–Gold Nanoparticles Affect Wharton’s Jelly Phenotype and Secretome during Tri-Lineage Differentiation

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    Multiple studies have demonstrated that various nanoparticles (NPs) stimulate osteogenic differentiation of mesenchymal stem cells (MSCs) and inhibit adipogenic ones. The mechanisms of these effects are not determined. The aim of this paper was to estimate Wharton’s Jelly MSCs phenotype and humoral factor production during tri-lineage differentiation per se and in the presence of silicon–gold NPs. Silicon (SiNPs), gold (AuNPs), and 10% Au-doped Si nanoparticles (SiAuNPs) were synthesized by laser ablation, characterized, and studied in MSC cultures before and during differentiation. Humoral factor production (n = 41) was analyzed by Luminex technology. NPs were nontoxic, did not induce ROS production, and stimulated G-CSF, GM-CSF, VEGF, CXCL1 (GRO) production in four day MSC cultures. During MSC differentiation, all NPs stimulated CD13 and CD90 expression in osteogenic cultures. MSC differentiation resulted in a decrease in multiple humoral factor production to day 14 of incubation. NPs did not significantly affect the production in chondrogenic cultures and stimulated it in both osteogenic and adipogenic ones. The major difference in the protein production between osteogenic and adipogenic MSC cultures in the presence of NPs was VEGF level, which was unaffected in osteogenic cells and 4–9 times increased in adipogenic ones. The effects of NPs decreased in a row AuNPs > SiAuNPs > SiNPs. Taken collectively, high expression of CD13 and CD90 by MSCs and critical level of VEGF production can, at least, partially explain the stimulatory effect of NPs on MSC osteogenic differentiation

    On the Development and Application of Multiple Cases for Accreditation of Health Care Professionals

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    The sequence for the development of the multiple case methodology (training technology) for accreditation of health care professionals has been presented. The multidimensionality of cases allows to cover all functions of professional standards. To improve the technique reliability, the multiple-choice tests have been offered. The requirement of local independence of tasks has been implemented. The results of approbation of cases with participation of 114 graduates (6th year) of 5 medical universities have been analysed. The interpretation of the analysis results and their use for assessing the professional readiness of health care professionals have been offered

    Gut Microbiota as a Mediator of Essential and Toxic Effects of Zinc in the Intestines and Other Tissues

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    The objective of the present study was to review the existing data on the association between Zn status and characteristics of gut microbiota in various organisms and the potential role of Zn-induced microbiota in modulating systemic effects. The existing data demonstrate a tight relationship between Zn metabolism and gut microbiota as demonstrated in Zn deficiency, supplementation, and toxicity studies. Generally, Zn was found to be a significant factor for gut bacteria biodiversity. The effects of physiological and nutritional Zn doses also result in improved gut wall integrity, thus contributing to reduced translocation of bacteria and gut microbiome metabolites into the systemic circulation. In contrast, Zn overexposure induced substantial alterations in gut microbiota. In parallel with intestinal effects, systemic effects of Zn-induced gut microbiota modulation may include systemic inflammation and acute pancreatitis, autism spectrum disorder and attention deficit hyperactivity disorder, as well as fetal alcohol syndrome and obesity. In view of both Zn and gut microbiota, as well as their interaction in the regulation of the physiological functions of the host organism, addressing these targets through the use of Zn-enriched probiotics may be considered an effective strategy for health management
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