59 research outputs found

    Электрохимические свойства наночастиц серебра на графитовом электроде

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    В настоящей работе было показано, что наночастицы серебра, полученные при молярном соотношении реагентов [AgNO3]: [Na3C6H5O7] = 1:1 в условии отсутствии стабилизатора с высоким молекулярным весом, обладают максимальной электрохимической активностью, что связано с неполным восстановлением ионов серебра. Этот факт соотносится с данными УФ-спектроскопии. Наночастицы серебра, полученные в избытке восстановителя при молярном соотношении реагентов [AgNO3]: [Na3C6H5O7] = 1:5 электрохимически неактивны, что также соответствует данным УФ- спектроскопии. Увеличение активности наночастиц серебра происходит в условии увеличения диапазона изменения потенциала, что может быть вызвано образованием перекиси водорода, обладающей активационной способностью. В данной работе установлены оптимальные условия, в которых наночастицы серебра являются наиболее электрохимически активны

    Detection of CRISPR cassettes and cas genes in the Arabidopsis thaliana genome

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    The state of the art in the evolution of plant viruses allows the genetic foundations of antiviral immunity in higher (including the most important crops) plants to be categorized as one of the most pressing issues of genetics and selection. According to the endosymbiotic theory, mitochondria descended from alphaproteobacteria that had been absorbed but not degraded by the host cell. The discovery of CRISPR-Cas systems (clustered regularly interspaced short palindromic repeats (CRISPR)-associated proteins), which implement the adaptive immunity function in prokaryotes, raises the question whether such a mechanism of antiviral protection could be caught up by evolution and used by representatives of eukaryotes (in particular, plants). The purpose of this work was to analyze the complete sequences of nuclear, mitochondrial, and chloroplast genomes of Arabidopsis thaliana in order to search for genetic elements similar to those in CRISPR-Cas systems of bacteria and archaea. As a result, in silico methods helped us to detect a locus of regularly intermittent short direct repeats in the mitochondrial genome of A. thaliana ecotypes. The structure of this locus corresponds to the CRISPR locus of the prokaryotic adaptive antiviral immune system. The probable connection between the locus found in the mitochondrial genome of the higher plant and the function of adaptive immunity is indicated by a similarity between the spacer sequences in the CRISPR cassette found and the genome of Cauliflower mosaic virus affecting Arabidopsis plants. Sequences of repeats and spacers of CRISPR cassettes in Arabidopsis C24 and Ler lines are perfectly identical. However, the locations of the CRISPR locus in the mitochondrial genomes of these lines differ significantly. The CRISPR cassette in the Col-0 line was found to be completely broken as a result of four deletions and one insertion. Although cas genes were not detected in the mitochondrial genome of the studied Arabidopsis ecotypes, their presence was detected in the nuclear genome. Both cas genes and numerous CRISPR cassettes were found on all the five chromosomes in the nuclear genome of the Col-0 ecotype. The results suggest the existence of a system of adaptive immunity in plants, which is similar to the CRISPR immunity of bacteria and archaea

    ANALIZA STANJA NAPREZANJA OBLOGE OKNA NA KONTAKTNOJ ZONI ANHIDRITA I KAMENE SOLI

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    The main question of this paper is the stress-strain state prediction of the vertical shaft’s combined lining located at the interface of two layers of dolomite and salt. The study predicts geomechanical processes at the contact of the dolomite layer and the salt layer in the vicinity of the vertical shaft’s expanded section, taking into account the operating life of a vertical shaft is equal to 50 years. The results combined lining’s stress-strain state, represented as a four – layer medium, where the external layer is concrete, and the three inner layers are used to account for the heterogeneity of cast-iron tubing and are compared with the results received when taking into account the pipe structure. The solution of the problem was carried out in a three-dimensional statement. The calculation of the tubing lining, considering its actual geometry, will increase the accuracy of the forecast of the stress state of the lining, which in turn will favourably affect the justification of its parameters.Glavna problematika ovoga rada očituje se u predviđanju stanja naprezanja – deformacije kombinirane obloge vertikalnoga okna smještene na kontaktu dvaju slojeva dolomita i soli. Studija predviđa geomehaničke procese na kontaktu dolomitnoga sloja i sloja soli u blizini proširenoga presjeka vertikalnoga okna, uzimajući u obzir radni vijek okna od 50 godina. Rezultati stanja naprezanja – deformacija kombinirane četveroslojne obloge, gdje je vanjski sloj beton, a tri unutarnja sloja od lijevanoga željeza, uzimajući u obzir heterogenost, uspoređeni su s rezultatima dobivenim kada je u obzir uzeta isključivo struktura cijevi. Rješenje problema provedeno je u trodimenzionalnome sustavu. Proračun obloge cijevi, uzimajući u obzir stvarnu geometriju, povećat će točnost predviđanja stanja naprezanja obloge, što upućuje na važnost parametara obloge

    A facility to Search for Hidden Particles (SHiP) at the CERN SPS

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    A new general purpose fixed target facility is proposed at the CERN SPS accelerator which is aimed at exploring the domain of hidden particles and make measurements with tau neutrinos. Hidden particles are predicted by a large number of models beyond the Standard Model. The high intensity of the SPS 400~GeV beam allows probing a wide variety of models containing light long-lived exotic particles with masses below O{\cal O}(10)~GeV/c2^2, including very weakly interacting low-energy SUSY states. The experimental programme of the proposed facility is capable of being extended in the future, e.g. to include direct searches for Dark Matter and Lepton Flavour Violation.Comment: Technical Proposa

    On-Line Student Modeling for Coached Problem Solving Using Bayesian Networks

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    This paper describes the student modeling component of ANDES, an Intelligent Tutoring System for Newtonian physics. ANDES' student model uses a Bayesian network to do long-term knowledge assessment, plan recognition and prediction of students' actions during problem solving. The network is updated in real time, using an approximate anytime algorithm based on stochastic sampling, as a student solves problems with ANDES.The information in the student model is used by ANDES' Help system to tailor its support when the student reaches impasses in the problem solving process. In this paper, we describe the knowledge structures represented in the student model and discuss the implementation of the Bayesian network assessor. We also present a preliminary evaluation of the time performance of stochastic sampling algorithms to update the network

    Успешное применение комбинированной экстракорпоральной поддержки жизнеобеспечения при лечении новой коронавирусной инфекции, осложненной развитием полиорганной дисфункции у беременной

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    Pregnant and postpartum women are at a higher risk of infection with SARS-CoV-2 as well as a higher risk of adverse outcomes for the mother and fetus. Standard approaches to the management of COVID-19-associated multiple organ dysfunction may not always be implemented in this category of patients. In the clinical case of a patient, who developed multiple organ dysfunction syndrome (severe ARDS, coagulopathy) associated with COVID-19 in the postpartum period, we demonstrate the successful use of combined extracorporeal life support that included veno-venous extracorporeal membrane oxygenation, therapeutic plasma exchange and renal replacement therapy with the universal oXiris set.Беременные и родильницы подвержены более высокому риску заражения новой коронавирусной инфекцией и неблагоприятным исходам как для матери, так и для плода. Стандартные подходы к ведению полиорганной дисфункции, ассоциированной с COVID-19, не всегда могут быть осуществлены в этой группе больных за счет измененной физиологии дыхательной системы у беременных и неблагоприятного влияния на плод. На примере пациентки, у которой на фоне COVID-19 развился синдром множественной органной дисфункции (острый респираторный дистресс-синдром тяжелой степени (PaO2/FiO 2 96), коагулопатия), продемонстрировано успешное применение в послеродо­вом периоде комбинированной экстракорпоральной поддержки жизнедеятельности, сочетающей в себе вено-венозную экстракорпоральную мембранную оксигенацию, терапевтический плазмообмен и заместительную почечную терапию с использованием универсального сета oXiris

    Методические рекомендации Российской некоммерческой общественной организации «Ассоциация анестезиологов-реаниматологов», Межрегиональной общественной организации «Альянс клинических химиотерапевтов и микробиологов», Межрегиональной ассоциации по клинической микробиологии и антимикробной химиотерапии (МАКМАХ), общественной организации «Российский Сепсис Форум» «Диагностика и антимикробная терапия инфекций, вызванных полирезистентными штаммами микроорганизмов» (обновление 2022 г.)

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    Strains of microorganisms characterized by resistance to antimicrobial drugs used in medical organizations continue to spread In most regions of the world including Russia. It is clear that it affects both the effectiveness of antimicrobial therapy and tactics and strategy of its use not only in adults patients but also in children. The pandemic of coronavirus infection, in addition, highlighted the growing problems in treatment of invasive mycoses, the dose adjustment of antibiotics during sorption and dialysis therapy methods. These circumstances made it necessary to make adjustments to Guidelines on Diagnostics and Antimicrobial Therapy of Infections Caused by Multiresistant Strains of Microorganisms, which were prepared by a group of leading Russian experts in 2020 [1]. The submitted version of the recommendations was approved on 25.03.2022 at a joint meeting of the working group with representatives of public organizations: Association of Anesthesiologists-Intensivists, the Interregional Non-Governmental Organization Alliance of Clinical Chemotherapists and Microbiologists, the Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy (IACMAC), and NGO Russian Sepsis Forum. These recommendations reflect an interdisciplinary consensus opinion on approaches to the diagnosis and antimicrobial therapy of infections caused by multiresistant microorganisms. They are based on data from publications obtained from randomized trials as well as based on international clinical guidelines with a high degree of evidence.It is rational to use the Guidelines for determining the tactics of empirical and etiotropic therapy of the most severe infections.В большинстве регионов мира, в том числе и в России, продолжают распространяться штаммы микроорганизмов, характеризующиеся устойчивостью к используемым в медицинских организациях антимикробным препаратам. Понятно, что это закономерно влияет как на эффективность антимикробной терапии, так и на тактику и стратегию ее применения не только у взрослых, но и у детей. Пандемия коронавирусной инфекции, кроме того, высветила нарастающие проблемы с лечением инвазивных микозов, подбором дозирования антибактериальных средств при использовании методов сорбционной и диализной терапии. Эти обстоятельства обусловили необходимость внести коррективы в Методические рекомендации «Диагностика и антимикробная терапия инфекций, вызванных полирезистентными штаммами микроорганизмов», которые были подготовлены группой ведущих российских экспертов в 2020 г. [1]. Представляемый вариант рекомендаций был утвержден 25.03.2022 г. на совместном заседании рабочей группы с представителями общественных организаций: Российской некоммерческой общественной организации «Ассоциация анестезиологов-реаниматологов», Межрегиональной общественной организации «Альянс клинических химиотерапевтов и микробиологов», Межрегиональной ассоциации по клинической микробиологии и антимикробной химиотерапии (МАКМАХ), общественной организации «Российский Сепсис Форум». Данные рекомендации отражают междисциплинарное консенсусное мнение о подходах к диагностике и антимикробной терапии инфекций, вызванных полирезистентными микроорганизмами. В их основу положены данные из публикаций, полученные в ходе рандомизированных исследований, а также положения, изложенные в международных клинических рекомендациях, имеющие высокую степень доказательности.Изложенные в Рекомендациях положения целесообразно использовать при определении тактики эмпирической и этиотропной терапии наиболее тяжелых инфекций

    A facility to Search for Hidden Particles (SHiP) at the CERN SPS

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    A new general purpose fixed target facility is proposed at the CERN SPS accelerator which is aimed at exploring the domain of hidden particles and make measurements with tau neutrinos. Hidden particles are predicted by a large number of models beyond the Standard Model. The high intensity of the SPS 400~GeV beam allows probing a wide variety of models containing light long-lived exotic particles with masses below O{\cal O}(10)~GeV/c2^2, including very weakly interacting low-energy SUSY states. The experimental programme of the proposed facility is capable of being extended in the future, e.g. to include direct searches for Dark Matter and Lepton Flavour Violation

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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