Stand-alone hydropower plants based on magnetoelectric generator and transistor converters

В докладе рассматриваются вопросы разработки мини-ГЭС на базе синхронного генератора с постоянными магнитами и с активным выпрямителем и инвертором напряжения в качестве преобразователей энергии. Обсуждаются вопрос выбора силовых частей, структура системы управления и синтез регуляторов активного выпрямителя напряжения. Приведены результаты применения наблюдателя тока нагрузки АВН.The report discusses the development of mini-hydro -based synchronous permanent magnet generator and active rectifier and inverter voltage as energy converters . Discussed the question of choice of power units, control system structure and synthesis of active rectifier voltage regulators . The results of application of the load current observer VAR

Research the methods of construction positional ac drive

В докладе рассматриваются вопросы построения позиционных электроприводов переменного тока. Обсуждаются различные варианты построения структуры системы управления и синтеза регуляторов. Приведены результаты теоретических исследований системы позиционирования с частотно-регулируемым асинхронным электроприводом.The report below concentrates on the construction of positional AC drives. There discussed the various methods of construction the structure of control system and the synthesis of controllers. There presented the results of theoretical researches positional system with frequency-controlled induction motor drive

АТРЕЗИЯ ТОЛСТОЙ КИШКИ В СОЧЕТАНИИ С БОЛЕЗНЬЮ ГИРШПРУНГА: РЕДКОЕ КЛИНИЧЕСКОЕ НАБЛЮДЕНИЕ

Introduction. Hirschsprung’s disease is a congenital anomaly characterized by the absence of ganglion cells in submucosal and intramuscular layers of intestinal wall that leads to the intestinal obstruction. 70–80 % of cases are isolated malformation but it can be combined with chromosomal abnormalities and other malformations. Coexistence of Hirschsprung’s disease with intestinal atresia is extremely rare. It can cause significant difficulties in diagnostics and treatment.Material and methods. Patient A, a boy, was transferred to the surgical department at the age of two days with a history of intestinal obstruction. He had abdominal X-ray studies: intestinal obstruction. The contrast enema showed microcolon that was coiled in the pelvis. Patient was prepared to the surgical treatment. Intraoperatively colonic atresia was identified at 10 sm from the ileocecal valve. A double colostomy was performed to the child and biopsy on the level of mucous fistula was taken. Histological study showed the aganglionosis of the distal colon. At the age of 4 months, the patient underwent Soave-Swenson endorectal pullthrough procedure with intraoperative extended express-biopsy that confirmed the absence of ganglion cells in whole distal bowel. The aganglionic part was resected, the ileocecal valve with the part of the colon of 10 cm long was mobilized and the endorectal bringing the colon down to the perineum was performed by Soave – Swenson. Postoperative recovery was uneventful.Results. A high index of suspicion is required to promptly diagnose Hirschsprung’s disease in a child with colonic atresia despite the rare combination of these two anomalies. In this case the histological study allowed to recognize association of colonic atresia with Hirschsprung’s disease and helped to avoid complications after further surgery.Conclusions. Early detection of coexisting of these two anomalies helps to prevent the development of serious postoperative complications. Введение. Болезнь Гиршпрунга – врожденное заболевание, которое характеризуется отсутствием нервных ганглиев в подслизистом и межмышечном слоях кишечной стенки, приводящее к нарушению пассажа содержимого по желудочно-кишечному тракту. В 70–80 % случаев является изолированным пороком развития, однако может сочетаться с хромосомными патологиями и другими аномалиями. Сочетание болезни Гиршпрунга с атрезией тонкой или толстой кишки встречается довольно редко и может вызвать значительные трудности в диагностике и лечении.Материал и методы. Мальчик А. был переведен в стационар в возрасте 2 суток жизни с клиникой низкой кишечной непроходимости. Обследован рентгенологически: картина кишечной непроходимости. При ирригографии, помимо картины микроколона, обращало на себя внимание необычное расположение толстой кишки в малом тазу. Подготовлен к оперативному лечению. Интраоперационно выявлена атрезия толстой кишки на расстоянии 10 см от илеоцекального угла. Ребенку наложена двойная колостома, взята биопсия отводящей и приводящей кишки. По гистологическому заключению – аганглиоз отключенной кишки. В 4 месяца выполнена радикальная операция. Интраоперационно произведена расширенная экспресс-биопсия толстой кишки, ганглии выявлены только в приводящем отделе. Аганглионарный участок резецирован, мобилизован илеоцекальный угол с участком толстой кишки длиной 10 см и произведено эндоректальное низведение толстой кишки на промежность по Soave – Swenson. Послеоперационный период – без хирургических осложнений.Результаты. Несмотря на довольно редкое сочетание этих двух патологий, при оперативном лечении по поводу атрезии толстой кишки необходимо помнить о вероятности аганглиоза отводящего отдела. В данном случае гистологическое исследование участка отводящей кишки позволило рано выявить сочетание порока с болезнью Гиршпрунга и избежать возможных осложнений при последующем оперативном вмешательстве. Выводы. Раннее выявление сочетания двух аномалий позволит предупредить развитие тяжелых послеоперационных осложнений.

Измерение температурного и напряженно-деформированного состояний трубного образца при воздействии локальных стохастических температурных пульсаций

Provding a high level of durability of heat exchange equipment of water-cooled reactors under local stochastic temperature pulsations is an important scientific and technical problem for the nuclear power industry. Temperature pulsations produced by mixing non-isothermal coolant flows with high temperature gradient are most dangerous. This work is an experimental study of temperature and stress-strain state of a tube sample under local stochastic temperature pulsations caused by mixing of coolant flows.To solve the problems posed, a Y-junction with «counter injection» was built, which was included in the thermal-hydraulic research facility. The design of the Y-junction allows study of the thermal-hydraulic characteristics and durability of tube samples made of austenitic steel of 60 × 5 мм. Some tube samples had developed for measuring the temperature, stress-strain state of tube material and temperature field of coolant flow in mixing zone of single-phase coolants with different temperatures. Measuring tube samples were equipped with micro thermocouples and strain gauges.The experimental data of temperature pulsations, time-averaged temperature field in the coolant flow and on the outer surface of the sample were obtained, and statistical and spectral correlation characteristics of temperature pulsations were analyzed. According to results of measuring the relative strain, values of stresses were calculated.Devices and research techniques are developed. The combination of coolant flows parameters that provide thermal load of the metal surface at the highest level of stress intensity amplitude was obtained. The study results are used to verify the method for evaluating fatigue of reactor installations materials under stochastic temperature pulsations.Обеспечение ресурса теплообменного оборудования водоохлаждаемых реакторных установок при случайных пульсациях температуры является важной научно-технической задачей атомной энергетики. Наиболее опасны термопульсации, вызываемые смешением потоков рабочих сред при высоких градиентах температуры. Целью работы являлось экспериментальное исследование температурного и напряженно-деформированного состояний трубного образца при воздействии локальных термопульсаций, обусловленных смешением потоков теплоносителя.Для решения поставленных задач изготовлен тройниковый узел типа «встречный впрыск», включенный в состав теплофизического исследовательского стенда. Конструкция узла позволяет проводить исследования теплогидравлических и ресурсных характеристик трубных образцов 60 × 5 мм, изготовленных из сталей аустенитного класса. Разработаны средства измерения температурного, напряженно-деформированного состояний трубного образца и температурного поля потока теплоносителя в зоне смешения однофазных сред с различной температурой. Измерительные модели оснащены микротермопарами и тензорезисторами. В результате исследований получены массивы экспериментальных данных, содержащих реализации термопульсаций, осредненные во времени профили температуры потока и наружной поверхности трубного образца, статистические и спектрально-корреляционные характеристики термопульсаций. По результатам измерения относительных деформаций определены значения усталостных напряжений.Разработаны устройства и методики исследования. Установлены комбинации режимных параметров, обеспечивающих термосиловое нагружение поверхности металла с наиболее высоким уровнем амплитуд переменных напряжений. Полученные данные используются для верифицирования метода оценки усталостной долговечности конструкционных материалов реакторных установок при случайных термопульсациях

Stimulation of homology-directed gene targeting at an endogenous human locus by a nicking endonuclease

Homologous recombination (HR) is a highly accurate mechanism of DNA repair that can be exploited for homology-directed gene targeting. Since in most cell types HR occurs very infrequently (∼10−6 to 10−8), its practical application has been largely restricted to specific experimental systems that allow selection of the few cells that become genetically modified. HR-mediated gene targeting has nonetheless revolutionized genetics by greatly facilitating the analysis of mammalian gene function. Recent studies showed that generation of double-strand DNA breaks at specific loci by designed endonucleases greatly increases the rate of homology-directed gene repair. These findings opened new perspectives for HR-based genome editing in higher eukaryotes. Here, we demonstrate by using donor DNA templates together with the adeno-associated virus (AAV) Rep78 and Rep68 proteins that sequence- and strand-specific cleavage at a native, predefined, human locus can also greatly enhance homology-directed gene targeting. Our findings argue for the development of other strategies besides direct induction of double-strand chromosomal breaks to achieve efficient and heritable targeted genetic modification of cells and organisms. Finally, harnessing the cellular HR pathway through Rep-mediated nicking expands the range of strategies that make use of AAV elements to bring about stable genetic modification of human cells

Optimization of insect cell based protein production processes - online monitoring, expression systems, scale-up

Due to the increasing use of insect cell based expression systems in research and industrial recombinant protein production, the development of efficient and reproducible production processes remains a challenging task. In this context, the application of online monitoring techniques is intended to ensure high and reproducible product qualities already during the early phases of process development. In the following chapter, the most common transient and stable insect cell based expression systems are briefly introduced. Novel applications of insect cell based expression systems for the production of insect derived antimicrobial peptides/proteins (AMPs) are discussed using the example of G. mellonella derived gloverin. Suitable in situ sensor techniques for insect cell culture monitoring in disposable and common bioreactor systems are outlined with respect to optical and capacitive sensor concepts. Since scale-up of production processes is one of the most critical steps in process development, a conclusive overview is given about scale up aspects for industrial insect cell culture processes

Designer Gene Delivery Vectors: Molecular Engineering and Evolution of Adeno-Associated Viral Vectors for Enhanced Gene Transfer

Gene delivery vectors based on adeno-associated virus (AAV) are highly promising due to several desirable features of this parent virus, including a lack of pathogenicity, efficient infection of dividing and non-dividing cells, and sustained maintenance of the viral genome. However, several problems should be addressed to enhance the utility of AAV vectors, particularly those based on AAV2, the best characterized AAV serotype. First, altering viral tropism would be advantageous for broadening its utility in various tissue or cell types. In response to this need, vector pseudotyping, mosaic capsids, and targeting ligand insertion into the capsid have shown promise for altering AAV specificity. In addition, library selection and directed evolution have recently emerged as promising approaches to modulate AAV tropism despite limited knowledge of viral structure–function relationships. Second, pre-existing immunity to AAV must be addressed for successful clinical application of AAV vectors. “Shielding” polymers, site-directed mutagenesis, and alternative AAV serotypes have shown success in avoiding immune neutralization. Furthermore, directed evolution of the AAV capsid is a high throughput approach that has yielded vectors with substantial resistance to neutralizing antibodies. Molecular engineering and directed evolution of AAV vectors therefore offer promise for generating ‘designer’ gene delivery vectors with enhanced properties

Exchange of functional domains between a bacterial conjugative relaxase and the integrase of the human adeno-associated virus

Endonucleases of the HUH family are specialized in processing single-stranded DNA in a variety of evolutionarily highly conserved biological processes related to mobile genetic elements. They share a structurally defined catalytic domain for site-specific nicking and strand-transfer reactions, which is often linked to the activities of additional functional domains, contributing to their overall versatility. To assess if these HUH domains could be interchanged, we created a chimeric protein from two distantly related HUH endonucleases, containing the N-terminal HUH domain of the bacterial conjugative relaxase TrwC and the C-terminal DNA helicase domain of the human adeno-associated virus (AAV) replicase and site-specific integrase. The purified chimeric protein retained oligomerization properties and DNA helicase activities similar to Rep68, while its DNA binding specificity and cleaving-joining activity at oriT was similar to TrwC. Interestingly, the chimeric protein could catalyse site-specific integration in bacteria with an efficiency comparable to that of TrwC, while the HUH domain of TrwC alone was unable to catalyze this reaction, implying that the Rep68 C-terminal helicase domain is complementing the TrwC HUH domain to achieve site-specific integration into TrwC targets in bacteria. Our results illustrate how HUH domains could have acquired through evolution other domains in order to attain new roles, contributing to the functional flexibility observed in this protein superfamily.This work was supported by the Medical Research Council (MRC) grant MR/N022890/1 to EH and grant 1001764 to RML; National Institutes of Health (NIH) grant RO1-GM09285 to CRE; Spanish Ministry of Economy and competitiveness (MINECO) grant BIO2013-46414-P to ML and AFM is supported by a Doc.Mobility fellowship from the Swiss National Science Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript