Elliptical motions of stars in close binary systems

Motions of stars in close binary systems with a conservative mass exchange are examined. It is shown that Paczynski-Huang model widely used now for obtaining the semi-major axis variation of a relative stars orbit is incorrect, because it brings about large mistakes. A new model suitable for elliptical orbits of stars is proposed. Both of reactive and attractive forces between stars and a substance of the flowing jet are taken into account. A possibility of a mass exchange at presence of accretion disk is considere

Primitive neuroectodermal tumor of the zygomaticoorbital complex: a rare location and ways of surgical repair of the area

Primitive neuroectodermal tumor in the zygomaticoorbital region is a rare neoplasm of the head and neck. Due to the necessity for wide radical excision of a primary tumor, there may be serious functional and cosmetic disorders that substantially affect quality of life in patients. Restoration of this region is one of the challenges of reconstructive surgery because of the specific features of the relief of bone structures. The paper describes a clinical case of the site of primitive neuroectodermal tumor in the zygomaticoorbital complex and a method for repairing postresectional defect and completely recovering the function of the organ of vision and aesthetic parameters of the face

Difficulties in differential diagnosis between obstructive and non-obstructive azoospermia

Introduction. The difference between obstructive and non-obstructive azoospermia (OA and NOA) is important for the choice of treatment tactics and adequate counseling of a married couple.Objective. To describe, analyze, and classify possible challenges in differentiating between two types of azoospermiaMaterials and methods. The retrospective review of database on surgical sperm retrieval attempts performed our hospital (n = 754). A subpopulation of 216 patients who were preliminary diagnosed with OA, was selected for further analysis. All patients had testicular pathology data following sperm retrieval attempt. Rate of reclassification was assessed as a primary outcome. Reclassified cases were further analyzed to find a possible reason for incorrect differential diagnosis.Results. Among 216 patients with initially suspected OA, 131 (60.6%) had evidence of spermatogenic dysfunction on pathological examination of seminiferous tubules. Multivariate regression analysis showed that only regular exposure to high temperatures was an independent predictor of NOA detection in patients with normal endocrine and clinical parameters (OR = 1.989; 95% CI = 1.101 – 3.595). Analysis of the decision tree showed that patients with inhibin B levels below 93 pg/ml had the highest risk of an incorrect initial diagnosis (82.6%).Conclusions. Differential diagnosis of OA and NOA is not such a simple task. Any case of azoospermia against the background of normal semen volume by default should be considered as a case of NOA if there is no anamnestic or clinical data clearly indicating obstruction. Regular exposure to high temperature is likely to cause azoospermia in men with initially severe disorders of spermatogenesis. Finally, the reference values of inhibin B offered by most laboratories are not intended to assess reproductive function

Association of hypertriglyceridemia with risk factors for cardiovascular and renal complications in individuals with high cardiovascular risk

Aim. To study clinical and functional manifestations of hypertriglyceridemia and its association with risk factors for cardiovascular and renal complications in individuals with high cardiovascular risk.Material and methods. The study included 272 patients (129 men and 143 women; mean age, 53,9±13,7 years) with a high cardiovascular risk, which was stratified using Systematic Coronary Risk Evaluation (SCORE) model by the presence of cardiovascular disease, and/or diabetes, and/or age ≥65 years, and/or blood pressure (BP) >180/110 mm Hg, and/or total cholesterol (TC) level >8,0 mmol/l. All study participants underwent clinical and paraclinical examination. Serum content of triglycerides (TGs) ≥1,7 mmol/L was considered hypertriglyceridemia (HTG). Depending on TG level, the entire sample was divided into 2 following subgroups: subgroup 1 (n=178) — serum triglycerides ≤1,6 mmol/l; subgroup 2 (n=94) — serum triglycerides ≥1,7 mmol/l, i.e. HTG.Results. We revealed significantly more persons with obesity (46,8%) and type 2 diabetes (28,7%) in HTG subgroup. There were 56,3% and 36,1% patients of HTG subgroup with hypertension (HTN) and coronary artery disease (CAD), respectively. A mid-high TG level (from 1,7 to 2,3 mmol/l) in the subgroup of patients with HTG was detected in 38,3% of cases. The serum content of TG from 2,3 to 5,6 mmol/l was detected in 54,2% of patients. TG level ≥5,6 mmol/l was detected in 7,5% of cases. In the subgroup of patients with HTG, high levels of systolic, diastolic and central (aortic) BP, body mass index, phosphorus, creatinine, cystatin C, estimated glomerular filtration rate (eGFR), and carotid intima-media thickness (IMT) were detected significantly more common. In the general sample, a significant direct relationship between TG concentration and cystatin C (r=0,168) and an inverse (negative) relationship with eGFR (r=-0,220) was obtained.Conclusion. Elevated serum TG levels are often observed in individuals with obesity, type 2 diabetes, hypertension and CAD. Patients with HTG had a pronounced cardiovascular and renal risk, including a significant increase in BP and carotid IMT, high levels of total cholesterol, low-density lipoprotein cholesterol, phosphorus, creatinine, cystatin C, and a decrease in eGFR. HTG was associated with an increase in serum cystatin C and a deterioration in renal nitrogen excretion

Влияние ограниченных ожогов кожи на течение и исход ингаляционной травмы

Introduction Inhalation injury (ini) makes burn disease more severe. However, it remains unexplored what is the minimum area of the burn that can significantly aggravate of the course of ini.The objective was to compare the incidence of acute respiratory failure (arf), pneumonia, and mortality between patients with ini and ini with superficial skin burns up to 3% total body surface area (tbsa).Material and methods 125 patients with ini and i–ii degree skin burns up to 3% tbsa were allocated into 4 groups: ini without skin burns, ini with burns up to 1% tbsa, up to 2%, and up to 3% tbsa.Results In the group with ini and skin burns up to 2%, the number of arf, pneumonia cases, and deaths did not statistically significantly differ from the ini group, however in group of ini and burns of more than 2% tbsa, there were more of those complications.Conclusion Skin burns of i–ii degree over 2% tbsa increase the incidence of acute respiratory failure, pneumonia, and death in patients with ini.РЕЗЮМЕ Известно, что ингаляционная травма (ИТ) ухудшает течение ожоговой болезни у тяжелообожженных. Однако остается неизвестным, как небольшие ожоги влияют на течение ИТ.ЦЕЛЬ Сравнительное изучение частоты острой дыхательной недостаточности (ОДН), пневмонии и смертельных исходов у пациентов с ИТ и ИТ с поверхностными ожогами кожи до 3% поверхности тела (п.т.).МАТЕРИАЛ И МЕТОДЫ 125 пациентов с ИТ и ожогами кожи I–II степени до 3% п.т. были распределены на четыре группы: ИТ без ожогов кожи, с ожогами до 1% п.т., до 2% п.т., до 3% п.т.РЕЗУЛЬТАТЫ В группах с ИТ и ожогами кожи до 2% п.т. число наблюдений ОДН, пневмонии и случаев смертельных исходов статистически значимо не отличалось от группы ИТ, а в группе ИТ и ожогами свыше 2% п.т. их было больше.ВЫВОДЫ Ожоги кожи I–II степени свыше 2% п.т. увеличивают частоту развития острой дыхательной недостаточности, пневмонии и случаев смертельных исходов у пациентов с ингаляционной травмой

НЕКОТОРЫЕ ТЕНДЕНЦИИ МИРОВОГО РЫНКА РЗМ И ПЕРСПЕКТИВЫ РОССИИ

The paper presents a review of some trends observed on the world market of rare-earth elements (REE). This review takes into account actual changes in the commercial and industrial policy of China and the current trends of REE consumption. Main characteristics of the modern REE markets are considered. The paper provides an assessment of world production volumes, world trade and prices. The article describes the REE market behavior in 2000–2020 and provides a forecast of main indicators and prices up to 2020. It contains a description of current world REE resources, production and trade over the main countries. In addition, the prices and the main buyers of REE are specified indicating the forecast of consumption. The prospects of the Russian REE market are estimated taking into account the «Development of the Rare and Rare-Earth Elements Industry» subprogram implemented as part of the State Program of the Russian Federation «Industry Development and Competitiveness Improvement». The purpose of the subprogram is to create a competitive rare-earth industry of an integrated production cycle in the Russian Federation in order to satisfy the needs of the domestic defense industry complex, civil industries and enter the foreign markets. It is noted that this subprogram should be upgraded with regard to changes in the market conditions and development of rare-earth elements production in the Russian Federation including by means of statutory, non-tariff and technical regulation. Loparite and apatite will remain the main sources of rare-earth elements as raw materials for industrial processing in Russia in the near future, while REE production from apatite will increase. It is emphasized that the prospects of REE development in Russia consist not so much in increasing the primary production as in establishing new plants consuming rare-earth products.Представлен анализ некоторых направлений развития мирового рынка редкоземельных металлов (РЗМ) с учетом происходящих изменений в торгово-промышленной политике Китая и тенденций потребления РЗМ. Рассматриваются основные характеристики современных рынков РЗМ, дана оценка объемов мирового производства, мировой торговли и цен. Описана динамика рынков в 2000–2017 гг. и сделан прогноз основных показателей и цен до 2020 г. Дан обзор современных мировых запасов РЗМ, производства и торговли по основным странам. Приведены цены и основные покупатели РЗМ, а также прогноз потребления. Сделана оценка перспектив отечественного рынка РЗМ с учетом выполнения в России подпрограммы «Развитие промышленности редких и редкоземельных металлов» государственной программы РФ «Развитие промышленности и повышение ее конкурентоспособности». Целью подпрограммы являлось создание в РФ конкурентоспособной редкоземельной промышленности полного технологического цикла для удовлетворения потребностей отечественного оборонно-промышленного комплекса, гражданских отраслей промышленности и выхода на зарубежные рынки. Отмечается необходимость актуализировать эту подпрограмму с учетом изменения рыночной конъюнктуры и развития производства редкоземельных металлов на территории РФ в промышленности, в том числе путем нормативного, нетарифного и технического регулирования. Основными источниками редкоземельного сырья в России для промышленной переработки на бли жайший период останутся лопарит и апатит, при этом производство РЗМ из апатита будет увеличиваться. Подчеркнуто, что перспективы развития РЗМ в РФ заключаются не столько в росте производства первичной продукции, сколько в создании новых производств, потребляющих редкоземельную продукцию.

Innovative Technics of Managing Engineers' Global Competencies

Higher education modernization in the CIS countries takes place under the conditions of dynamic changes in economy and society. These changes are determined by the social and economic development of the country and the world globalization processes - cross-border intercultural communication, knowledge transparency, and the establishment of information society. Educational globalization is a continuous process of creating a unified global educational system, in which the distinctions between its member educational systems are being blended

ИССЛЕДОВАНИЯ ПО ИЗВЛЕЧЕНИЮ ЦЕРИЯ ИЗ РАСТВОРОВ КОНЦЕНТРАТОВ РЕДКОЗЕМЕЛЬНЫХ МЕТАЛЛОВ ЭЛЕКТРОХИМИЧЕСКИМ И ЭКСТРАКЦИОННЫМ МЕТОДАМИ

In order to extract cerium from rare-earth metals (REM) recovered from Russian raw materials, the following modern domestic equipment was selected: OXITRON-58L-O2 diaphragm electrolyzer manufactured by LLC «Delfin Aqua» with the purpose of Ce(III) to Ce(IV) oxidation; EC-10FA centrifugal extractor manufactured by LLC «LIT» with the purpose of Ce(IV) extraction from the sum of REM. These units were used in the studies performed to identify conditions that would lead to cerium oxidation to a 4-valent state with the electrochemical method as well as to recover and clean Ce(IV) from rare-earth metals with the solvent extraction method. The experiments were performed with standardized test solutions of cerium nitrate and process solutions obtained using loparite concentrate from the Solikamsk Magnesium Plant. The conditions were identified and equipment operation modes were designed in order to enable the chosen electrolyzer model to achieve a degree of cerium oxidation in REM process solutions over 99 % at power consumption below 0,8 kW/h per 1 kg of CeO2, and extract cerium from REM concentrate solution using the laboratory cascade of 20 centrifugal extractors with further production of 99,6 % pure CeO2.Осуществлен выбор современного отечественного оборудования для извлечения церия из концентратов редкоземельных металлов (РЗМ), выделенных из российского сырья: диафрагменный электролизер OКСИТРОН-58Л-О2, изготовленный ООО «Делфин Аква», для проведения процесса окисления Ce(III) до Ce(IV); экстрактор центробежного типа модели ЭЦ-10ФА производства ООО «ЛИТ» для извлечения Ce(IV) из суммы РЗМ. На данном оборудовании проведены исследования режимов окисления церия до 4-валентного состояния электрохимическим методом, а также извлечения и очистки Се(IV) от РЗМ методом жидкостной экстракции. Эксперименты выполнены на модельных растворах нитрата церия и технологических растворах, полученных из лопаритового концентрата Соликамского магниевого завода. Определены условия и разработаны режимы работы оборудования, позволяющие на выбранной модели электролизера достичь степени окисления церия в технологических растворах РЗМ более чем на 99 % при расходе электроэнергии не более 0,8 кВт/ч на 1 кг СеО2, а на лабораторном каскаде из 20 экстракторов центробежного типа выделить церий из раствора концентрата РЗМ и получить СеО2 чистотой 99,6 %

Сравнительная оценка микробиологического статуса бронхиального содержимого донора и реципиента при трансплантации легких

This study was aimed at investigation of relationships between bronchial washing culture in post-transplant recipient and bronchial flora of the lung donor. Methods. A comparative analysis of bronchial washing cultures from 30 post-transplant lung recipients was performed. All lung donors were stratified to ideal, suboptimal and marginal donors according to the lung transplant suitability. Results. As a result, development of post-transplant pulmonary complications was directly related to bacterial flora of the donor lung. The incidence of pneumonia in post-transplant patients was 3.3% after transplantation of ideal donor lungs, 20% after transplantation of suboptimal donors lungs and 100% after transplantation of marginal donor lungs. Conclusion. The rate of pneumonia in transplanted lungs was directly related to bronchial flora in the donor lungs. This should be taken into account when planning antibacterial therapy after lung transplantation.Представлен анализ результатов микробиологического исследования бронхиальных смывов потенциальных доноров легких (n = 60). Материалы и методы. Проведен сравнительный анализ микробиологического статуса реципиентов (n = 30) после трансплантации легких. Все доноры легких по степени пригодности легочного трансплантата были разделены на 3 группы: «идеальные», субоптимальные и маргинальные. Результаты. По результатам анализа показана прямая зависимость развития легочных осложнений в посттрансплантационном периоде от микрофлоры донора легких. Частота развития пневмонии у пациентов группы «идеальных» доноров легких в посттрансплантационном периоде составила 3,3 %, субоптимальных доноров – 20 %, маргинальных – 100 %. Заключение. Установлена корреляция развития пневмонии в трансплантированных легких в зависимости от микрофлоры донора, что необходимо учитывать при планировании антибактериальной терапии в посттрансплантационном периоде

Surgical treatment analysis in patients with anterior cerebral artery rupture in the acute period of subarachnoid hemorrhage Hunt-Hess IV-V

The article contains the analysis of surgical treatment cases in patients with the anterior cerebral artery rupture who underwent surgery in the acute period of subarachnoid hemorrage Hunt-Hess IV-V. Assessment of clinical outcomes by the basic neurological scales such as (Rivermead, Rankin, NIHSS, Fisher) was also presented as well as the search of good, satisfactory and bad outcome predictors for those patients.Представлен анализ случаев хирургического лечения пациентов с разрывом аневризм передней мозговой артерии, оперированных в острейшем периоде субарахноидального кровоизлияния, с тяжестью состояния по шкале Hunt-Hess IV-V. Проведена оценка клинических исходов по основным неврологическим шкалам (Ривермид, Рэнкин, NIHSS, Fisher), а также выполнен поиск предикторов хорошего, удовлетворительного и плохого исходов для указанной категории пациентов