The investigation of hydrogen accumulation in zirconium alloy by thermostimulated gas evolution method

Thermostimulated gas evolution from zirconium alloy saturated by hydrogen E_125 versus deformation degree has been studied. Samples of zirconium were subjected to straining with relative lengthening 2,5; 5,0 and 10,0 %, then they were saturated with hydrogen by electrolyte method at current density 0,5 A/sm2 during 4 hours. Or vice versa, they were first saturated with hydrogen being subjected to deformation afterwards. The deformation of alloy samples results in trap formation with different energies of hydrogen bond. In this case both bond energy and hydrogen quantity caught in traps depends on both deformation size and succession of «deformation-saturation» actions. The values of hydrogen bond energies in traps are estimated. Types of traps are defined

Bovine hypodermosis is highly prevalent in Kazakhstan: Results of a first serological study

Background and Aim: Recent information on the occurrence of bovine hypodermosis in Kazakhstan is limited to the results of a few clinical studies in the northern and eastern regions. A first serological study aimed to obtain more data on its geographical distribution and to estimate the prevalence in this country. Materials and Methods: Serum samples collected from 891 dairy cows on 30 dairy farms in eight Kazakh provinces during the winter season 2015/2016 were examined for antibodies to Hypoderma spp. first-stage larval antigen using a commercially available enzyme-linked immunosorbent assay (IDEXX Bovine Hypodermosis Serum Antibody Test). Results: Overall, 73.6% (95% confidence interval: 70.6%–76.5%) of the cows sampled were seropositive for Hypoderma, and antibody-positive cows were found in 28 of 30 farms and in seven of eight provinces. Conclusion: The results suggest a high prevalence of bovine hypodermosis in Kazakhstan, for which the socioeconomic changes in agriculture and village life following the country’s independence are considered to be responsible

Intestinal parasitic pathogens of dogs from homeless animal shelters (Nur-Sultan, Kazakhstan)

shelter, dog, coprological study, prevalence, intestinal parasitesFaecal samples of 114 stray dogs older than one year of age and kept at the central animal shelter in Nur-Sultan City were examined by the Fuelleborn method for gastrointestinal parasites. Faecal stages of 6 different helminth and 2 protozoan parasites were detected in 49 (42.9%) of the samples: Toxascarisleonina eggs were most prevalent (29.8%) followed by Toxocaracanis (4.4%) and taeniid eggs, possibly of Echinococcus sp. eggs (4.4%), Dipylidiumcaninum egg capsules (3.6%), Trichurisvulpis eggs (1.8%), ancylostomatid eggs (1.8%). Cystoisosporacanisoocysts and Sarcocystis sp. sporocysts were detected in 4.4% and 0.9% of the samples, respectively. Mixed infections with T. leonina and other parasites were found in 17 cases (14.9%). These results showed that control of parasite infections in the animal shelter should be strongly improved, also to prevent the infection of humans with zoonotic parasites

Best Practices of Engineering Training in World Leading Universities

В статье-обзоре освещаются лучшие образовательные практики инженерно-технической подготовки в ведущих зарубежных университетах. Рассматривается современный контекст инженерно-технической подготовки, анализируются ожидания и запросы различных участников образовательного процесса, в том числе представителей промышленности. Основной задачей исследования являлось изучение лучших образовательных практик ведущих зарубежных университетов в области инженерно-технической подготовки, анализ образовательных политик университетов и поддерживающих их реализацию мероприятий. Обсуждаются нововведения в образовательной политике вузов, чей опыт инженерно-технической подготовки определяется новыми задачами реформирования образовательных программ посредством внедрения новых технологий активного, проектного, проблемного обучения с целью формирования у студентов ключевых профессиональных и востребованных межотраслевых профессионально значимых компетенций. Приводятся примеры организации учебного процесса в зарубежных университетах в сотрудничестве с работодателями, а также интегрированная в реальную производственную деятельность подготовка профессорско-преподавательского состава. Выводы авторов относительно изменений современного состояния инженерно-технической подготовки в ведущих зарубежных университетах представлены в рекомендательном ключе с целью возможного пилотирования и интеграции лучших практик в образовательную деятельность по подготовке инженеров в российских университетах.The paper reviews best educational practices in engineering training provided by world leading universities. Modern landscape of engineering training and education has been viewed; expectations and needs of different stakeholders of educational process have been considered, including those of industry representatives. The main purpose of our research is to study the educational practices of the world leading universities in engineering training, to analyze educational policies and training measures supporting their realisation. There are considered the innovations in educational policies of the universities whose experience in engineering training is determined by new objectives of reforming degree programmes via integrating new technologies of active, project-based, and problem-based learning in order to develop students’ key professional competences and generic skills. The examples of curriculum planning in collaboration with employers are viewed. The university staff training integrated into real industry operating is considered. The authors’ conclusions on the changes in the current state of engineering training are presented in the form of advice, with the orientation towards prospective piloting and integration of the best practices into engineering education in Russian universities

Стандартные образцы для градуировки анализатора водорода при высокой концентрации

The study discusses the issues of improving the accuracy of measuring high hydrogen concentrations in the development of storage materials in the hydrogen energy industry. The purpose of the study was to develop reference materials for calibration of the hydrogen analyzers at high concentrations. The main methods for determining the hydrogen content in materials were analyzed. It was established that the extraction method in an inert gas medium has found the widest application. The main methods for determining the hydrogen content in materials are analyzed, it is established that the extraction method in an inert gas medium has found the widest application. The need for calibration of analyzers on reference materials with a high hydrogen concentration was noted. Reference materials of titanium alloy VT-1-0 with hydrogen concentration up to (4.0±0.1) wt.% have been developed. The optimal parameters for the analysis were selected. On the example of the hydrogen analyzer RHEN602 (LECO, USA), calibration was carried out on the developed reference materials to obtain a calibration dependence. The reliability of the obtained calibration curve with the application of stoichiometric zirconium hydride was estimated. The confidence interval of the resulting calibration curve was ±10 %. It has been established that the calibration on the developed materials makes it possible to analyze materials with a hydrogen content of 0.5 to 4.0 wt.%. The practical significance of the study lies in the development of reference materials that can be applied to calibrate hydrogen analyzers operating on the principle of melting in an inert gas medium at a high hydrogen concentration.В данном исследовании рассматриваются вопросы повышения точности при измерении высоких концентраций водорода при разработке материалов-накопителей в водородной энергетике. Цель исследования – разработка стандартных образцов для градуировки анализаторов водорода при высоких концентрациях. Проанализированы основные методы определения содержания водорода в материалах, установлено, что экстракционный метод в среде инертного газа нашел наиболее широкое применение. Отмечена необходимость градуировки анализаторов по стандартным образцам с высокой концентрацией водорода. Разработаны стандартные образцы из титанового сплава ВТ-1-0 с концентрацией водорода до (4,0±0,1) масс.%. Подобраны оптимальные параметры проведения анализа. На примере анализатора водорода RHEN602 (LECO, США) проведена градуировка по разработанным стандартным образцам с получением градуировочной зависимости. Оценена надежность полученной градуировочной прямой с использованием стехиометрического гидрида циркония. Доверительный интервал полученной градуировочной прямой составил ±10 %. Установлено, что проведение градуировки по разработанным образцам позволяет проводить анализ материалов с содержанием водорода от 0,5 до 4,0 масс.%. Практическая значимость исследования заключается в разработке стандартных образцов, которые могут быть применены для проведения градуировки анализаторов водорода, работающих по принципу плавления в среде инертного газа, при высокой концентрации водорода.

Trichinellosis dissemination among wild carnivores in the Republic of Kazakhstan: A 10-year study

Background and Aim: Trichinellosis is caused by a species of roundworm called Trichinella and is an invasive disease causing severe medical, veterinary, and socioeconomic problems worldwide. More than 100 mammalian species are Trichinella hosts. Among domestic animals, pigs and dogs are prone to trichinellosis. An essential aspect of controlling the spread of infection is to identify the number and level of infections in wild carnivores in the country. However, the number, habitats, and movements of wild animal Trichinella hosts in Kazakhstan have not been reported yet. This study aimed to monitor the wild animal habitat nearby the settlements for tracking the trichinellosis speading among carnivores. Materials and Methods: Wild carnivorous animals were captured in seven regions of the Republic of Kazakhstan. The carcasses of corsacs, wolves, foxes, wild boars, and badgers were studied. Muscle tissue samples from spontaneously infected wild animals were collected. The digestion method in “GASTROS-2M” was used to isolate Trichinella spp. from animal muscles. The species of the parasite was determined by a polymerase chain reaction for 5S spacer of Trichinella ribosomal DNA with subsequent sequencing by Senger. Statistical analysis methods were performed for average value in Microsoft Excel 2010. Results: The results of the research showed that among 155 animals wolves (20.4%) and foxes (26.7%) were the most infected with invasive Trichinella larvae. The invasion intensity was 503.6% in foxes and 289.7% in wolves. However, badgers (164%), wild boars (0%), and corsacs (0%) presented lower invasion levels. Using specific primers, larvae samples were identified as Trichinella nativa. Conclusion: The results of monitoring revealed the spread of trichinosis among wild animals: wolves, foxes, badgers. The Karaganda, Kostanay, Western Kazakhstan, and Akmola regions had the largest distribution of wild animals infected with trichinellosis. In total, 20% of the 155 studied animals were infected. The greatest invasion intensity was typical for wolves, foxes and badgers. It is necessary to monitor the spread of trichinellosis among wild carnivores to control the epidemiological situation and reduce the level of spontaneous infection among animals. Regular monitoring of habitats and carnivores must be conducted within the country and in the border areas

СИНТЕЗ И СТРУКТУРА КОМПЛЕКСОВ ХЛОРИДА И БРОМИДА МЕДИ(II) С 4,5-ДИХЛОРИЗОТИАЗОЛ-N-(2-ГИДРОКСИЭТИЛ)-3-КАРБОКСАМИДОМ

Copper(II) chloride and bromide complexes with 4,5-dihlorizotiazol-N-(2-hydroxyethyl)-3-carboxamide (L) with the compositions [CuLHal2 ]n , where Hal = Cl– , Br– , are synthesized. The X-ray analysis revealed that the ligand is coordinated to the copper(II) atoms tridentate by the nitrogen atom of the heterocycle and two exocyclic oxygen atoms to form polymer chains. The copper bromide complex showed a synergistic effect in the compositions of insecticides Kerber and Vitan. Разработаны методики синтеза комплексов галогенидов меди(II) с 4,5-дихлоризотиазол-N-(2-гидрокси- этил)-3-карбоксамидом (L) состава [CuLHal2 ]n , где Hal = Cl– , Br– . Методом рентгеноструктурного анализа установлено, что лиганд координируется к атомам меди(II) тридентатно атомом азота гетероцикла и двумя экзоциклическими атомами кислорода, с образованием полимерных цепочек. Комплекс бромида меди проявил синергический эффект в композициях с инсектицидами Кербер и Витан.

Carotid endarterectomy in Russia. What if current guidelines do not answer difficult questions?

This literature review covers the publications of Russian vascular surgeons in recent years and deals with debatable issues of carotid surgery, including: 1. What is the best technique for carotid endarterectomy (CEA)? 2. Why does restenosis of the internal carotid artery (ICA) develop and how to eliminate it? 3. How to operate on bilateral ICA stenosis? 4. Should carotid glomus be preserved? 5. Is CEA safe in the acute phase of cerebrovascular accident (CVA)? 6. Is CEA safe in elderly patients? 7. How to operate on patients with combined internal carotid and coronary artery involvement? The evidence presented in this publication makes it possible to draw the following conclusions: 1. When choosing a CEA technique, the classical technique with patch angioplasty should be avoided due to the high risk of ICA restenosis. 2. To eliminate ICA restenosis, carotid angioplasty with stenting (CAS) should be used. When performing primary CEA with ICA transposition over the hypoglossal nerve, reCEA can be used 3. In the absence of contraindications, bilateral ICA stenosis can be operated at the same time using CEA. 4. CEA with carotid glomus preservation is the operation of choice in the treatment of patients with hemodynamically significant ICA stenosis due to the elimination of the risks of postoperative hypertension and the formation of hemorrhagic transformation. 5. If there are indications for cerebral revascularization in the most acute period of stroke, CEA should be abandoned in favor of CAS. 6. In old age, CAS is the safest treatment strategy. 7. In the presence of a combined ICA and coronary involvement, the choice of treatment tactics should be carried out only by a multidisciplinary commission, taking into account the risk stratification of adverse cardiovascular events

Многоцентровое исследование по изучению течения резистентной артериальной гипертензии после классической и эверсионной каротидной эндартерэктомии

Aim of study. Analysis of the dynamics of resistant arterial hypertension (RAH) and the spectrum of adverse cardiovascular events in patients after classical carotid endarterectomy (CEE) with preservation of carotid body (CB) and eversion CEE with CB transection.Material and methods. This cohort, comparative, retrospective, open-label study from January 2014 to December 2020 included 761 patients with hemodynamically significant stenosis of the internal carotid arteries (ICA) and RH lasting more than 3 years. Depending on the implemented revascularization strategy, 2 groups were formed: Group 1: 38.0% (n=289) — classical CEE with plasty of the reconstruction zone with a patch (made of diepoxy-treated xenopericardium or synthetic); Group 2: 62% (n=472) — eversion CEE with CB transection. To study the dynamics of systolic blood pressure (SBP) in the preoperative period for 4 days, and in the postoperative period, blood pressure was measured for 10 days (during the period when the patient was in intensive care - according to daily monitoring of blood pressure; in the department - 10 times per day, daily). The average SBP figures for all patients were taken into account when constructing a graph of BP fluctuations.Results. In the postoperative period, the groups were comparable in the frequency of the following events: death (group 1: 0.34% (n=1), group 2: 0.63% (n=3); p=0.98; OR 0.54; 95% CI 0.05–5.21), myocardial infarction (group 1: 0.34% (n=1), group 2: 0.84% (n=4); p=0.71; OR 0, 40; 95% CI 0.04–3.65), ischemic stroke (group 1: 0.34% (n=1), group 2: 1.27% (n=6); p=0.36; OR 0.26; 95% CI 0.03–2.25), hemorrhagic transformation (group 1: 0%, group 2: 0.84% (n=4); p=0.29; OR 0.17; 95% CI 0.009–3.35). However, in terms of the number of all complications (death + myocardial infarction + ischemic stroke + hemorrhagic transformation) presented as a combined endpoint, patients after eversion CEE with CB transection were three times superior to classical surgery (group 1: 1.03% (n=3 ), group 2: 3.60% (n=17); p=0.05; OR 0.28; 95% CI 0.08–0.9).Conclusion. The choice of a revascularization strategy in patients with hemodynamically significant ICA stenosis should be personalized and based on the conclusion of a multidisciplinary consultation, and not only on the preferences of the operating surgeon. In patients with RH, it is more expedient to use classical CEE with plasty of the reconstruction zone with a patch in view of the preservation of the CB during this operation. The intersection of the latter with eversion CEE provokes labile hypertension, progression of RAH and a statistically significant increase in the number of all unfavorable cardiovascular events. Thus, the use of carotid body preserving CEE in patients with RAH confirms the therapeutic mechanism of this manipulation in achieving the target SBP level. Цель. Анализ динамики резистентной артериальной гипертензии (РАГ) и спектра неблагоприятных кардиоваскулярных событий у пациентов после классической каротидной эндартерэктомии (КЭЭ) с сохранением каротидного гломуса (КГ) и эверсионной КЭЭ с отсечением КГ.Материал и методы. В данное когортное сравнительное ретроспективное открытое исследование за период с января 2014 г. по декабрь 2020 г. вошел 761 пациент с гемодинамически значимыми стенозами внутренних сонных артерий (ВСА) и РАГ длительностью более 3 лет. В зависимости от реализованной стратегии реваскуляризации были сформированы две группы: 1-я группа: 38,0% (n=289) — классическая КЭЭ с пластикой зоны реконструкции заплатой (из диэпоксиобработанного ксеноперикарда или синтетическая); 2-я группа: 62% (n=472) — эверсионная КЭЭ с отсечением КГ. Для изучения динамики систолического артериального давления (САД) в дооперационном периоде в течение 4 суток, а в послеоперационном периоде в течение 10 суток измерялось артериальное давление — АД (в период нахождения пациента в реанимации — по данным суточного мониторинга АД; в отделении — 10 раз в сутки ежедневно). Средние цифры САД по всем больным учитывали при построении графика колебания АД.Результаты. В послеоперационном периоде группы оказались сопоставимы по частоте следующих событий: смерть (группа 1: 0,34% (n=1), группа 2: 0,63% (n=3); р=0,98; ОШ 0,54; 95% ДИ 0,05–5,21), инфаркт миокарда (группа 1: 0,34% (n=1), группа 2: 0,84% (n=4); р=0,71; ОШ 0,40; 95% ДИ 0,04–3,65), ишемический инсульт (группа 1: 0,34% (n=1), группа 2: 1,27% (n=6); р=0,36; ОШ 0,26; 95% ДИ 0,03– 2,25), геморрагическая трансформация (группа 1: 0%, группа 2: 0,84% (n=4); р=0,29; ОШ 0,17; 95% ДИ 0,009–3,35). Однако по числу всех осложнений (смерть + инфаркт миокарда + ишемический инсульт + геморрагическая трансформация), представленных в виде комбинированной конечной точки, пациенты после эверсионной КЭЭ с пересечением КГ превосходили классическую операцию в 3 раза (группа 1: 1,03% (n=3), группа 2: 3,60% (n=17); р=0,05; ОШ 0,28; 95% ДИ 0,08–0,9).Заключение. Выбор стратегии реваскуляризации у пациентов с гемодинамически значимым стенозом внутренних сонных артерий должен быть персонифицированным и основываться на заключении мультидисциплинарного консилиума, а не только на предпочтениях оперирующего хирурга. У пациентов с резистентной артериальной гипертензией более целесообразно применение классической каротидной эндартерэктомии с пластикой зоны реконструкции заплатой ввиду сохранения каротидного гломуса во время данной операции. Пересечение последнего при эверсионной каротидной эндартерэктомии провоцирует лабильную артериальную гипертензию, прогрессирование резистентной артериальной гипертензии и статистически значимое возрастание числа всех неблагоприятных кардиоваскулярных событий. Таким образом, применение гломус-сберегающей каротидной эндартерэктомии у пациентов с резистентной артериальной гипертензией подтверждает лечебный механизм данной манипуляции в достижении целевого уровня систолического артериального давления.