50 research outputs found
Электрохимические свойства наночастиц серебра на графитовом электроде
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
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
The effect of cutting conditions on power inputs when machining
Any technological process involving modification of material properties or product form necessitates consumption of a certain power amount. When developing new technologies one should take into account the benefits of their implementation vs. arising power inputs. It is revealed that procedures of edge cutting machining are the most energy-efficient amongst the present day forming procedures such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc, such as physical and technical methods including electrochemical, electroerosion, ultrasound, and laser processing, rapid prototyping technologies etc. An expanded formula for calculation of power inputs is deduced, which takes into consideration the mode of cutting together with the tip radius, the form of the replaceable multifaceted insert and its wear. Having taken as an example cutting of graphite iron by the assembled cutting tools with replaceable multifaceted inserts the authors point at better power efficiency of high feeding cutting in comparison with high-speed cutting
Detection of gene clusters for biodegradation of alkanes and aromatic compounds in the Rhodococcus qingshengii VKM Ac-2784D genome
Bacterial species of the genus Rhodococcus are known to be efficient degraders of hydrocarbons in contaminated soil. They are also employed for bioremediation of polluted environments. These bacteria are widely met in soil, water and living organisms. Previously, we have isolated the Rhodococcus qingshengii strain VKM Ac-2784D from the rhizosphere of couch grass growing on oil-contaminated soil. This strain can effectively degrade oil and some model compounds (naphthalene, anthracene and phenanthrene). The results of phylogenetic analysis show that this strain belongs to the species R. qingshengii. To understand the catabolic properties of this strain, we have studied its gene clusters possessing such properties. The alkane destruction genes are represented by two clusters and five separate alkB genes. The destruction of aromatic compounds involves two stages, namely central and peripheral. The R. qing shengii VKM Ac-2784D genome contains four out of eight known central metabolic pathways for the destruction of aromatic compounds. The structure of the gene clusters is similar to that of the known strains R. jostii RHA1 and R. ru ber Chol-4. The peripheral pathways include the genes encoding proteins for benzoic acid destruction. The presence of biphenyl 2,3-dioxygeneses as well as gene clusters of benzoate and 2-hydroxypentandienoate pathways suggests that R. qingshengii VKM Ac-2784D could degrade polychlorinated biphenyls. The biodegradation ability can be enhanced by biosurfactants, which are known to be synthesized by Rhodococcus. The R. qingshengii VKM Ac-2784D genome contains the otsA, otsB, treY, treZ genes. The bioinformatics data are supported by the previous biochemical experiments that allow a mixture of species with a wide variation of metabolic pathways to be obtained
Estimating the cutting force when skiving with a radius cutter
The paper considers the method of determining the components of the cutting force under cutting completed with a radius cutter. The authors provide the design of the experimental study. The authors provide the data on the cutting force change in the process of turning with a radius cutter according to the cutting edge inclination, cutting depth and supply obtained experimentally and calculated analytically. The paper also provides the results of experimental work approximation and theoretical error checking related to experimental data
A facility to Search for Hidden Particles (SHiP) at the CERN SPS
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 (10)~GeV/c,
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
Успешное применение комбинированной экстракорпоральной поддержки жизнеобеспечения при лечении новой коронавирусной инфекции, осложненной развитием полиорганной дисфункции у беременной
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
A facility to Search for Hidden Particles (SHiP) at the CERN SPS
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 (10)~GeV/c, 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
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.)
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
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 (10)~GeV/c, 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