Optical and structural properties of the GaAs heterostructures grown using AlGaAs superlattice buffer layer on compliant Si(100) substrates with the preformed porous-Si (por-Si) layer

360 nm and 700 nm thick GaAs layers were grown by MO MOCVD growth technique directly on compliant Si (100) substrate and on supper-lattice (SL) AlGaAs buffer layer. The XRD study revealed better structural quality for the sample grown on SL / por-Si buffer. AFM study revealed a smoother sample surface with blocks of more regular rectangular shape and larger size as well. Photoluminescence spectra of the samples revealed an energy shift of PL maximum intensity for both samples. Sample grown on SL buffer also showed higher PL intensity corresponding to better crystalline perfection

Kinetics and mechanism of the pudovik reaction in the azomethine series: II.1 Hydrolysis and catalysis in the reaction of dialkyl phosphites with benzalaniline

A 31P NMR study show that diisopropyl phosphite and benzalaniline do not react with each other as individual components. Adduct formation is made possible by partial hydrolysis of the dialkyl phosphite

НОВАЯ ВЫСЕВАЮЩАЯ СИСТЕМА ДЛЯ ДИФФЕРЕНЦИРОВАННОГО ВНЕСЕНИЯ МИНЕРАЛЬНЫХ УДОБРЕНИЙ

The existing sowing systems (SS) of machines for fertilizers application not fully provide quality of introduction of mineral fertilizers. Unevenness and instability of application reach 20-40 percent at demanded to 15 percent. The SS equipped with glow coil of original design was offered for ensuring necessary quality of mineral fertilizers distribution across the field at their intra soil differentiated introduction. Flow rate of SS was regulated with the help of the executive mechanism with the linear actuator and a reducer modified for work with the block of control and management according to the prescription map. Researches were conducted on purpose: estimating of operability of new SS, with the new drive for change of frequency of rotation of the coil; establishments of functional dependences between flow rate of SS, i.e. ability to provide its necessary range of change of doses at the differentiated introduction of fertilizers; estimates of quality of work of experimental SS for the differentiated introduction of mineral fertilizers. Researches were carried out both in laboratory and field conditions. Functional dependence of flow rate of SS on number of turns of coils is received. It is established also that flow rate of SS directly depends on percent of opening of the actuator and frequency of rotation of the sowing coil. The minimumtime of transfer from one to other dose equals 0.9 seconds. It is established that at SS with the three experimental coil devices unevenness of seeding between devices makes 4.5 persent. Instability of seeding does not exceed 3 persent. The maximum values of unevenness of seeding between 3 sowing devices and instability of seeding between replications are received when opening of the actuator was 40 persent, and frequency of rotation - 22 rpm, which nevertheless, also meet requirements for the sowing systems.Существующие высевающие системы (ВС) машин для внесения минеральных удобрений не в полной мере обеспечивают качество их процесса: неравномерность внесения достигает 20-40 процентов при требуемой 15 процентов. Для обеспечения необходимого качества распределения минеральных удобрений по полю при дифференцированном внесении предложили ВС, оснащенную штифтовой катушкой оригинальной конструкции. Секундную подачу ВС регулировали с помощью исполнительного механизма с линейным актуатором и бесступенчатым редуктором, откорректированным для работы с блоком контроля и управления в соответствии с картой-заданием. Целью исследований стали оценка работоспособности новой ВС с приводом для изменения частоты вращения катушки, определение функциональных зависимостей между секундной подачей ВС и необходимым диапазоном изменения доз для качественного дифференцированного внесения удобрений. Исследования проводили как в лабораторных, так и в полевых условиях. Получили функциональную зависимость секундной подачи ВС от числа оборотов катушек. Определили, что она напрямую зависит от степени открытия актуатора и частоты вращения высевающей катушки. Минимальное время перехода с одной дозы на другую при 10-процентном открытии актуатора составляет 0,9 секунды. Установили, что у ВС с тремя экспериментальными катушечными аппаратами неравномерность высева между аппаратами составляет 4,5 процента, неустойчивость высева не превышает 3 процентов. Максимальные значения неравномерности высева 3 катушечных высевающих аппаратов и неустойчивости высева между повторностями получены при открытии актуатора на 40 процентов и частоте вращения 22 об/мин

ELM triggering conditions for the integrated modeling of H-mode plasmas

Recent advances in the integrated modeling of ELMy H-mode plasmas are presented. A model for the H-mode pedestal and for the triggering of ELMs predicts the height, width, and shape of the H-mode pedestal and the frequency and width of ELMs. Formation of the pedestal and the L-H transition is the direct result of ExB flow shear suppression of anomalous transport. The periodic ELM crashes are triggered by either the ballooning or peeling MHD instabilities. The BALOO, DCON, and ELITE ideal MHD stability codes are used to derive a new parametric expression for the peeling-ballooning threshold. The new dependence for the peeling-ballooning threshold is implemented in the ASTRA transport code. Results of integrated modeling of DIII-D like discharges are presented and compared with experimental observations. The results from the ideal MHD stability codes are compared with results from the resistive MHD stability code NIMROD.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France

Scalable Production and Purification of Adeno-Associated Viral Vectors (AAV).

Here we describe methods for the production of adeno-associated viral (AAV) vectors by transient transfection of HEK293 cells grown in serum-free medium in orbital shaken bioreactors and the subsequent purification of vector particles. The protocol for expression of AAV components is based on polyethyleneimine (PEI) mediated transfection of a 2-plasmid system and is specified for production in milliliter to liter scales. After PEI and plasmid DNA (pDNA) complex formation the diluted cell culture is transfected without a prior concentration step or medium exchange. Following a 3-day batch process, cell cultures are further processed using different methods for lysis and recovery. Methods for the purification of viral particles are described, including iodixanol gradient purification, immunoaffinity chromatography, and ultrafiltration, as well as quantitative PCR to quantify vector titer

Association of polymorphisms near the FOXC2 gene with the risk of varicose veins in ethnic Russians

© The Author(s) 2015.Objective: To investigate the association of polymorphisms located near the FOXC2 gene with the risk of varicose veins in ethnic Russians. Methods: Allele, genotype, and haplotype frequencies were determined in the sample of 474 patients with primary varicose veins and in the control group of 478 individuals without a history of chronic venous disease. Results: Polymorphisms rs7189489, rs4633732, and rs1035550 showed the association with the increased risk of varicose veins, but none of the observed associations remained significant after correction for multiple testing. Haplotype analysis revealed the association of haplotype rs7189489 C–rs4633732 T–rs34221221 C–rs1035550 C–rs34152738 T–rs12711457 G with the increased risk of varicose veins (OR = 2.67, P = 0.01). Conclusions: Our results provide evidence that the studied polymorphisms do not play a major role in susceptibility to varicose veins development in the Russian population

Polymorphisms in the MTHFR and MTR genes and the risk of varicose veins in ethnical Russians

© 2016 Informa UK Limited, trading as Taylor & Francis GroupObjectives: The objective of this study was to study the association of polymorphisms MTHFR C677T (rs1801133) and MTR A2756G (rs1805087) with the risk of varicose veins in ethnical Russians. Methods: We genotyped 475 patients with varicose veins, 168 individual without chronic venous disease, and the population-based group of 896 subjects. Association was studied using logistic regression analysis adopting co-dominant, additive, recessive, and dominant models of inheritance. Results: None of the polymorphisms showed a statistically significant association with the risk of varicose veins. Conclusions: Our results provide evidence that the studied polymorphisms do not contribute to genetic susceptibility to varicose veins in ethnical Russians

Polymorphisms in the MTHFR and MTR genes and the risk of varicose veins in ethnical Russians

© 2016 Informa UK Limited, trading as Taylor & Francis Group.Objectives: The objective of this study was to study the association of polymorphisms MTHFR C677T (rs1801133) and MTR A2756G (rs1805087) with the risk of varicose veins in ethnical Russians. Methods: We genotyped 475 patients with varicose veins, 168 individual without chronic venous disease, and the population-based group of 896 subjects. Association was studied using logistic regression analysis adopting co-dominant, additive, recessive, and dominant models of inheritance. Results: None of the polymorphisms showed a statistically significant association with the risk of varicose veins. Conclusions: Our results provide evidence that the studied polymorphisms do not contribute to genetic susceptibility to varicose veins in ethnical Russians

Surgical Aid to Patients with Hepatopancreatobiliary Situations in Precovid Period and under Persistent Relapse of New Coronavirus Infection SARS-CoV-2

Introduction. The third wave of the new coronavirus infection (COVID-19) pandemic warrants total mobilisation of healthcare and social resources. In this respect, a pressing issue remains the provision of routine and emergency surgical care in patients with hepatopancreatobiliary diseases.Materials and methods. A retrospective analysis of the surgical outcomes in 5,040 hepatopancreatobiliary patients was carried out; this accounted for 51.1 % of the total abdominal surgeries.Results and discussion. Biliary lithiasis and its complications — choledocholithiasis with obstructive jaundice and residual choledocholithiasis — (54.4 %) as well as acute calculous cholecystitis (18.7 %) were operated most frequently. A sharp decrease over all hepatopancreatobiliary nosologies was registered for the surgical interventions in first pandemic year 2020. Thus, the median annual number of operations for biliary lithiasis and its complications was 550 (482–592 year-range) in the precovid period, while dropping to only 321 at the onset of pandemic (p <0.05). A first sixmonth survey of year 2021 revealed a growth of surgical activity for all hepatopancreatobiliary nosologies.Conclusion. Hepatopancreatobiliary operations prevail (54.4 % cases) in the total structure of level 3 abdominal surgical interventions. A high annual rate of surgical operations over nearly all hepatopancreatobiliary nosologies was interrupted in the first year of the new coronavirus infection outbreak. Meanwhile, the first half of 2021 showed a clear tend towards restoring the precovid statistical indicators, despite the stressful conditions of persistently relapsing COVID-19 that surgical facilities had faced