Аналитическое и экспериментальное исследование деформации деталей шарошечного долота

Distribution of load between the cutting elements of the roller cutter drill bit depends on several factors, among them on the stiffness of the drilling-bit assembly. To deduce the dependencies of the stiffness of the drilling-bit assembly on the drill bit design and the point of application of the external load, the scheme of static interaction of the rolling cutter drill bit with the non-deformable bottom hole is considered. The calculation results allow to conclude, that the vertical stiffness of the drilling bit assembly has a maximum value at the contact with the bottom hole of the middle teeth rows of the roller cutters. For verification of the results of the analytical calculations the experimental measurements of the vertical movements of the rolling cutters of the roller cutter drill bit at the contact of those with bottom hole with the teeth of the different teeth rows have been made. The proposed methodology can be used to optimize the design of the roller cutter drill bits at the blueprint stage.La distribución de la carga entre los elementos de un armamento de broca de rodillo depende de varios factores, incluida la rigidez del nudo de rodillo. Para obtener las dependencias de la rigidez de una junta de rodillo en el diseño de la broca y el punto de aplicación de una carga externa, se considera un esquema de interacción estática de una broca de rodillo con una cara no deformable. Los resultados del cálculo nos permiten concluir que la rigidez vertical del nudo del rodillo tiene un valor máximo en contacto con la parte inferior de los bordes centrales del cono del rodillo. Para verificar los resultados de los cálculos analíticos, se realizaron mediciones experimentales del movimiento vertical de los conos de bits cuando estaban en contacto con los dientes de varias coronas. La técnica propuesta se puede utilizar para optimizar el diseño de las brocas de rodillo en la etapa de diseño.Распределение нагрузки по элементам вооружения шарошечного долота зависит от ряда факторов, в том числе от жесткости шарошечного узла. Для получения зависимостей жесткости шарошечного узла от конструкции долота и точки приложения внешней нагрузки рассматривается схема статического взаимодействия шарошечного долота с недеформируемым забоем. Результаты расчетов позволяют сделать вывод о том, что вертикальная жесткость шарошечного узла имеет максимальное значение при контакте с забоем средних венцов шарошки. С целью проверки результатов аналитических расчетов проведены экспериментальные измерения вертикального перемещения шарошек долота при контакте их с забоем зубками различных венцов. Предлагаемая методика может использоваться для оптимизации конструкции шарошечных долот на стадии их проектирования

Neutrophil granulocytes: participation in homeostatic and reparative processes. Part II

A supportive homeostatic function of neutrophilic granulocytes is accomplished in the physiology of diverse tissues and body systems. Neutrophils are found along the entire female reproductive tract (FRT), gradually declining in numbers from the upper parts towards the vagina. At the same time, both quantity and activity of FRT mucosal neutrophils are controlled by hormonal changes at different phases of menstrual cycle. Tissue neutrophils serve as an important source of broad-spectrum proteolytic enzymes such as matrix metalloproteinases and elastase necessary for extracellular matrix remodeling as well as vascular endothelial growth factor (VEGF) required for physiological FRT angiogenesis. During pregnancy, decidual neutrophils play a prominent role in vascular remodeling in pregnant uterus as well as development of maternal-fetal immune tolerance. The influx of neutrophils into the intestinal mucosa due to its trauma or infection not only ensures defense against pathogens, but also leads to increased proliferation of intestinal epithelial cells. Neutrophilic granulocytes elicit signals and events protective for the epithelium by marking them with a “hypoxic signature” to trigger transcription of the gene set responsible for production of mucins, mucin-modifying peptides, antimicrobial proteins, в-defensins, ultimately contributing to lesion healing and recovery of epithelial barrier function. “Inflammatory hypoxia” initiated by neutrophils and subsequent stabilization of the transcription factor hypoxia-induced factor (HIF) in intestinal epithelial cells trigger mechanisms of self-limited and resolved inflammation, which prevent excessive accumulation of neutrophils in the intestinal lumen and development of chronic inflammatory process. Neutrophilic granulocytes dominate in the oral cavity mucosa and comprise more than 95% of total leukocyte population recruited into the gingival sulcus and gingival fluid. Neutrophils maintain physiological amount and stability of symbiotic microflora composition in dental and gingival biofilms, counteracting pathogenic bacteria via phagocytosis, degranulation and extracellular trap formation, thereby ensuring healthy state in periodontal structures. Finally, similar to some other congenital disorders affecting neutrophil quantity and functions it was shown that in case of leukocyte adhesion deficiency type 1 (LAD-1) pathogenesis of periodontitis may not only be associated with a defect in their protective effector activity, but also with altered immunoregulatory function of tissue neutrophils

Neutrophil granulocytes: participation in homeostatic and reparative processes. Part I

After exiting from the bone marrow (BM) into the circulation, mature neutrophil granulocytes undergo a set of sequential phenotypic and physiological changes collectively called “aging” in the absence of inflammation, by constitutively sensing prime signals from commensal microbiota and acquiring higher functional alertness in case of activation upon tissue damage or pathogen invasion. Physiological aging of blood neutrophils and their subsequent return to the BM result in signals modulating size and function of the hematopoietic niche. Circadian physiological infiltration of BM by neutrophils contributes to maintaining baseline level of circulating hematopoietic progenitor cells capable of regeneration and immune surveillance. Apart from the BM, neutrophils actively enter other healthy tissues, probably exerting some effects on their baseline physiologic state. Using lung tissue, it has been shown that neutrophils can “govern” action of gene set regulating cell growth, migration, proliferation, differentiation, and carcinogenesis. Neutrophils participate in destruction of endometrial tissues during desquamation phase as well as subsequent repair and physiological angiogenesis during proliferative phase of the menstrual cycle; promote wall rupture of the preovulatory ovarian follicle and oocyte exit; contribute to degradation and resorption of the corpus luteum in pregnancy failure; play an important physiological role in vascular remodeling in pregnant uterus and developing maternal immune tolerance to semi-allogeneic fetus. Neutrophils actively migrating to the surface of intestinal epithelium during local infection and/or damage stimulate epithelial restitution and recovery of its barrier function. On the other hand, neutrophils recruited into the oral cavity regulate quantitative and qualitative composition of microbial communities in oral biofilms, and ensure healthy state of periodontal structures. Being a major player and regulator in healing of skin wounds at early stage, inflammation, neutrophils not only destroy potential pathogens, but also participate in cleansing wounds from cell debris, produce cytokines, enzymes, and growth factors affecting further stages in repair process. Both apoptosis and NETosis underlying neutrophil death greatly contribute to wound healing. However, dysregulation and imbalance in both apoptosis and NETosis may lead to unfavorable consequences as well as developing chronic non-healing wounds

High-pole LED lighting system

Different kinds of design of the 25-meter high-pole LED lighting system with 16 or 9 LED Street Lights “Phoenix” mounted on its crown (corona) have been suggested. The crown consists of two tiers. Some luminaries (8 or 4 pcs.) are installed on the first tier at an angle 1, while the other half is on the second tier at an angle 2 relative to the horizon plane. Based on the lighting simulation results, optimal luminaire orientation angles were defined as α₁ = 30° and α₂ = 50°, which provides uniform illumination of an area 100x100 m by size with the average luminance level 9.25 lu

Разнообразие субпопуляций регуляторных Т-клеток

Regulatory T-lymphocytes play a central role in the immunological tolerance system. To date, existence of many different subpopulations of regulatory T-cells have been described. However, a number of questions related to the function, differentiation, and homeostasis of these subpopulations in a body remain unclear. Interactions between the previously discovered pairs of helper and regulatory T-lymphocytes require further study. The main topic is identification and establishment of the functions of regulatory memory cells. Interstitial migration of activated regulatory T-lymphocytes is also a promising direction. In this review, we summarized the main findings in multiple subsets of regulatory T-lymphocytes, discussed unclear data that will require further studies, and  showed an application for regulatory T-lymphocytes in medicine.Регуляторные Т-лимфоциты являются центральными клетками системы иммунологической толерантности. В настоящее время описано существование множества различных субпопуляций регуляторных Т-клеток (Treg), однако большое количество вопросов, касающихся функционального назначения, путей дифференцировки и гомеостаза этих субпопуляций в организме, остаются неизученными. Продемонстрированные ранее пары хелперов и соответствующих им регуляторных Т-лимфоцитов требуют дальнейшего изучения их взаимодействий друг с другом. Актуальной темой является идентификация и установление функций клеток регуляторной памяти. Тканевая миграция активированных регуляторных Т-лимфоцитов также является перспективным направлением. В этом обзоре собраны и систематизированы данные о различных субпопуляциях регуляторных Т-лимфоцитов, выделены актуальные вопросы данной тематики, требующие дальнейшего изучения, а также затронуты пути развития области в клинической медицине

Роль нейтрофилов в патогенезе ишемического инсульта

Background. Immune responses and inflammation play an important role in the pathogenesis of ischemic stroke.Aim. To analyze the involvement of neutrophils in the pathogenesis of ischemic stroke.Results. Data on the contribution of neutrophil granulocytes to the development of local sterile inflammation and secondary brain injury in acute ischemic stroke were summarized. Mechanisms of neutrophil influence on thrombosis, neutrophil extracellular trap formation (NETosis), protease release, and direct interaction with platelets with subsequent formation of platelet-leukocyte aggregates were discussed. Available information on the effectiveness of reperfusion therapy and an association of changes in neutrophil activity with development of infectious complications of stroke were presented. In addition, research data were presented on the contribution of neutrophils to atherogenesis, which is one of the most important etiological factors in ischemic stroke. The review showed that the contribution of neutrophils to the pathogenesis of ischemic stroke is associated with implementation of their secretory, regulatory, and phagocytic functions, as well as with NETosis.Conclusion. It was shown that neutrophils are involved in the pathogenesis of ischemic stroke and modulate a response to treatment.Актуальность. Иммунные реакции и воспалительный процесс играют важную роль в патогенезе ишемического инсульта.Цель. На основании научных публикаций проанализировать вовлеченность нейтрофилов в патогенез ишемического инсульта.Результаты. Обобщены данные о вкладе нейтрофильных гранулоцитов в развитие локального асептического воспаления и вторичного повреждения мозга при остром инсульте. Обсуждены механизмы влияния нейтрофилов на процесс тромбообразования, образование нейтрофильных внеклеточных ловушек (нетоз), высвобождение протеаз и прямое взаимодействие с тромбоцитами с образованием лейкоцитарно-тромбоцитарных агрегатов. Приведены имеющиеся сведения об эффективности реперфузионной терапии, а также ассоциации изменений активности нейтрофилов с развитием инфекционных осложнений инсульта. Представлены данные исследований о вкладе нейтрофилов в атерогенез, являющийся одним из важнейших этиологических факторов ишемического инсульта. Показано, что участие нейтрофилов в патогенезе ишемического инсульта связано с реализацией их секреторных, регуляторных, фагоцитарных функций и с нетозом.Заключение. Установлено, что нейтрофилы принимают активное участие в патогенезе ишемического инсульта и модулируют ответ на лечение

Сравнительное исследование эффективности инвестиций в инновации на примере электроэнергетических компаний группы «Газпром»

The results of energy companies development in Russia in 2005-2009 are studied using the proposed efficiency model based on DEA analysis theory statements. The model lets estimate the efficiency of usage of own and attracted investment aimed at innovative development of companies. It is proposed to research efficiency of energy companies using the parameter of total investment used for several years for supporting the company activity, development and introduction of innovative technologies. The model was used for comparison of productive efficiency of companies belonging to JSC Gazprom and detection of differences in the usage rate of own and attracted investment resources applied for development and supporting the working state of facilities.Результаты развития энергетических компаний в России в 2005-2009 гг. изучены с помощью предлагаемой модели эффективности, построенной на положениях теории DEA-анализа. Модель позволила оценить эффективность использования собственных и привлекаемых инвестиций, направляемых на инновационное развитие компаний. Предлагается исследовать эффективность энергетических компаний с применением параметра суммарных инвестиций, направляемых в течение ряда лет на поддержание деятельности компании, развитие и внедрение инновационных технологий. С помощью модели сопоставлена производственная эффективность компаний ОАО «Газпром», обнаружены различия в степени использовании собственных и привлекаемых инвестиционных ресурсов, направляемых на развитие и поддержание мощностей в рабочем состоянии