48 research outputs found

    Proposal for a Listening Comprehension Oriented Classroom -With focus on interpretation practise-

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    © 2016 American Chemical Society.Interaction of 4,5-dimethyl-2-(2-oxo-1,2-diphenyl)ethoxy-1,3,2-dioxaphospholane, bearing a carboxyl group in the γ-position with respect to the phosphorus atom and obtained from d,l-butanediol, with hexafluoroacetone (CCl4, -40 °C) leads to the simultaneous formation of regio- and stereoisomeric cage-like phosphoranes with phosphorus-carbon and phosphorus-oxygen bonds with a high stereoselectivity (>95%), whose structure was determined by 1D and 2D NMR spectroscopy and XRD. When stored as a solution in dichloromethane for one month, the PCO-isomer rearranges into the thermodynamically more stable POC-isomer of the cage-like phosphorane. Mild hydrolysis of the PCO/POC-isomers proceeds with a high chemoselectivity and leads to the formation of P(IV)-dioxaphospholane derivatives. Acidic hydrolysis of the POC-isomer leads to the formation of an oxirane derivative with an unexpectedly high stereoselectivity (>95%). DFT calculations (using the PBE functional) allowed us to obtain structures and energies of the initial phospholane, reaction products (PCO/POC-isomers), and an intermediate P(V)-oxaphosphirane

    Research of the wastewater treatment method for the production of wood-chip building materials in the presence of nanostructured heterogeneous catalys

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    ABSTRACT: Introduction. Phenols and petroleum products are common wastewater contaminants in many industries. Due to their persistence and toxicity in the natural environment, an efficient waste disposal technology is needed. Ozonation in the presence of heterogeneous catalysts is one of the advanced methods for treating wastewater from these toxicants. Since most catalysts are expensive, they are being sought on the basis of transition metals and their oxides, which have high activity and relatively low cost. In this regard, the Scientific and Educational Center for Innovative Technologies (SECIT) of USPTU carried out work on the search for an effective and affordable catalyst for the deep oxidation of phenol and petroleum products in wastewater under the influence of ozone. Methods and materials. To study catalytic ozonation, we used model waste water containing phenol and oil products at concentrations of 8 and 30 mg/dm3, respectively. Ozonation was carried out in the presence of fresh (1) and spent (2) NiO–MoO3 catalyst deposited in the form of a film on cylindrical Al2O3 granules weighing 0.5 – 2 g. Results. Optimal conditions of ozonation have been found (1), within 10 min of the decomposition process in its presence, COD decreased by 25% compared to the oxidation process with a catalyst (2), and by 40% compared to classical ozonolysis. It was found that the optimal loading of catalyst (1) is 1 g, duration is 35 min, pH = 8.5, temperature – 22 – 30оC, ozone dose – 5 g/dm3. Discussion. At catalyst dosages of less than 1 g/dm3 , the low efficiency of removing phenol and hydrocarbons is probably due to a lack of the adsorption surface of the catalyst. Conclusion. The studied method of purification allows to reduce the content of phenol and oil products to the standard indicator of drinking water quality (0.001 and 0.05 mg/dm3, respectively), COD by 96% and solve the problem of the harmful effects of these toxicants on ecosystems

    Protease Activated Receptor Signaling Is Required for African Trypanosome Traversal of Human Brain Microvascular Endothelial Cells

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    Human African trypanosomiasis, or sleeping sickness, occurs when single-cell trypanosome protozoan parasites spread from the blood to brain over the blood-brain barrier (BBB). This barrier is composed of brain microvascular endothelial cells (BMECs) especially designed to keep pathogens out. Safe drugs for treating sleeping sickness are lacking and alternative treatments are urgently required. Using our human BMEC BBB model, we previously found that a parasite protease, brucipain, induced calcium activation signals that allowed this barrier to open up to parasite crossing. Because human BMECs express protease-activated receptors (PARs) that trigger calcium signals in BMECs, we hypothesized a functional link between parasite brucipain and BMEC PARs. Utilizing RNA interference to block the production of one type of PAR called PAR-2, we hindered the ability of trypanosomes to both open up and cross human BMECs. Using gene-profiling methods to interrogate candidate BMEC pathways specifically triggered by brucipain, several pathways that potentially link brain inflammatory processes were identified, a finding congruent with the known role of PAR-2 as a mediator of inflammation. Overall, our data support a role for brucipain and BMEC PARs in trypanosome BBB transmigration, and as potential triggers for brain inflammation associated with the disease

    Principles of Projecting Preschool Education Institutions

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     This article describes the principles of projecting of preschool facilities, sanatorium-type kindergartens in the village, the scope of services for kindergartens located in rural areas, the development of plans (analytical schemes) depending on their typ

    Pedagogical and Psychological Principles of the Formation of Communication Culture Between Teacher and Student

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    This article is devoted to the basis of improving behavior and communication culture between the attitudes of teachers and students. Mainly, the article is outlined for the educators and learners of the Institutes and Universities

    Challenges in Diagnostics and Management of Atypical Hemolytic Uremic Syndrome Associated with Acute Intestinal Infection in Adolescent: Clinical Case

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    Background. Acute intestinal infections (AII) caused by Shiga-like toxin-producing Escherichia coli and accompanied by hemolytic uremic syndrome (HUS) development are characterized by rapid progression and poor prognosis. Bloody diarrhea (hemorrhagic colitis) requires timely medical treatment both at young age and at adolescence. The severe course of HUS affected by AII caused by enterohaemorrhagic Escherichia coli requires additional medical attention and timely renal replacement therapy (hemodialysis).Clinical Case Description. The description and analysis of the severe course of HUS affected by AII in 14 years old adolescent girl is presented. There were some difficulties during diagnostics and thus the pathogenetic therapy onset was delayed. Differential diagnosis between typical and atypical HUS was performed. The disease was characterized by rapid progression of acute kidney injury, cerebrovascular disease and ischemia, multiple organ dysfunction syndrome and disseminated intravascular coagulation resulting in fatal case.Conclusion. Atypical HUS is the most frequent cause of multiple organ dysfunction syndrome alongside with acute kidney injury. The challenges of early diagnostics of atypical GUS in childhood are not fully solved nowadays and require additional attention of pediatricians. The clinical case of atypical GUS complicated by intestinal infection caused by enterohaemorrhagic Escherichia coli is described in this article. The severity of the disease course was due to the early manifestation of extrarenal symptoms and multiple organ failure
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