Use of accelerated helium-3 ions for determining oxygen and carbon impurities in some pure materials

Methods are developed for the determination of O impurity in Be and Si carbide and concurrent determination of C and O impurities in Si and W by irradiation with accelerated He-3 ions and subsequent activity measurements of C-11 and F-18 formed from C and O with the aid of a gamma-gamma coincidence spectrometer. Techniques for determining O in Ge and Ga arsenide with radiochemical separation of F-18 are also described

Phase transitions and phase diagram of the ferroelectric perovskite NBT-BT by anelastic and dielectric measurements

The complex elastic compliance and dielectric susceptibility of (Na_{0.5}Bi_{0.5})_{1-x}Ba_{x}TiO_{3} (NBT-BT) have been measured in the composition range between pure NBT and the morphotropic phase boundary included, 0 <= x <= 0.08. The compliance of NBT presents sharp peaks at the rhombohedral/tetragonal and tetragonal/cubic transitions, allowing the determination of the tetragonal region of the phase diagram, up to now impossible due to the strong lattice disorder and small distortions and polarizations involved. In spite of ample evidence of disorder and structural heterogeneity, the R-T transition remains sharp up to x = 0.06, whereas the T-C transition merges into the diffuse and relaxor-like transition associated with broad maxima of the dielectric and elastic susceptibilities. An attempt is made at relating the different features in the anelastic and dielectric curves to different modes of octahedral rotations and polar cation shifts. The possibility is also considered that the cation displacements locally have monoclinic symmetry, as for PZT near the morphotropic phase boundary.Comment: 11 pages, 9 figures, submitted to Phys. Rev.

Wave diffraction problems on periodical sets of heterogeneities in the stratified media

The universal approach to solving the diffraction problems on the periodical set of heterogeneities in the stratified media is proposed. The infinite periodic grating consisting of thin conducting bands embedded into a dielectric plate is considered as an example. The boundary value problem for the quasi-periodic potential functions is equivalent to the pair summatorial functional equation for the Floquet coefficients. At first, it is advisable to solve the auxiliary diffraction problem for the stratified medium in the case when the heterogeneities are moved off. The heterogeneities generate the field perturbation; it is a solution of a similar pair equation. Secondly, we need to define new unknown variables in such way that the pair equation should have the standard form. To get this result we propose to use the boundary value conditions on the heterogeneities. Then the other conditions on the media interface can be transformed to standard form. The dual equation is equivalent to regular infinite set of linear algebraic equations for the coefficients of decomposition of the electromagnetic field by Floquet harmonics. In the case of elastic waves the wave diffraction problems on the periodical sets of heterogeneities can be reduced to vector dual summatorial functional equations. The electromagnetic wave diffraction problems on the periodical knife grating was investigated by analogous scheme

Kinetics of fragmentation and dissociation of two-strand protein filaments: Coarse-grained simulations and experiments.

While a significant body of investigations have been focused on the process of protein self-assembly, much less is understood about the reverse process of a filament breaking due to thermal motion into smaller fragments, or depolymerization of subunits from the filament ends. Indirect evidence for actin and amyloid filament fragmentation has been reported, although the phenomenon has never been directly observed either experimentally or in simulations. Here we report the direct observation of filament depolymerization and breakup in a minimal, calibrated model of coarse-grained molecular simulation. We quantify the orders of magnitude by which the depolymerization rate from the filament ends koff is larger than fragmentation rate k- and establish the law koff/k- = exp[(ε‖ - ε⊥)/kBT] = exp[0.5ε/kBT], which accounts for the topology and energy of bonds holding the filament together. This mechanism and the order-of-magnitude predictions are well supported by direct experimental measurements of depolymerization of insulin amyloid filaments.This research was supported by the ERC, EPSRC, BBSRC, and the Newman Foundation.This is the author accepted manuscript. The final version is available from the American Institute of Physics via http://dx.doi.org/10.1063/1.496236

Applying Aniline for P-doping of PEDOT:PSS Films to Improve Their Conductivity and Efficiency of Perovskite Solar Cells

Poly(3,4- ethylenedioxythiophene):polystyrene sulfonate (PEDOT: PSS) is responsible for hole extraction efficiency and hole transport in the perovskite solar cell structure. The inclusion of PSS reduces the conductivity of the PEDOT films, which inhibits hole transport and results in a low photo current of the perovskite solar cell. In this work, an aniline solution was used as an additive in the PEDOT: PSS thin film to increase electrical conductivity. Two different methods were used to incorporate the additive: surface and volume treatment. The results show that the surface treatment with aniline solution can significantly increase the conductivity of PEDOT: PSS film. Moreover, the photoconversion efficiency of the perovskite solar cell with such a PEDOT: PSS layer is increased 1.5 times compared to the untreated one

ВАКЦИНОПРОФИЛАКТИКА КОРИ У ДЕТЕЙ С ПАТОЛОГИЕЙ ЦЕНТРАЛЬНОЙ НЕРВНОЙ СИСТЕМЫ

The data on the current vaccination process and specific antibody in 212 children with pathology of nervous systems in age from 1 year to 6 years old, vaccinated against measles. The comparison group consisted of 36 children without neurological disease. 86 children (40,6%) were vaccinated measles – mumps vaccine, and 126 children (59,4%) only measles vaccine. Post-vaccination period in 77,8% immunized against measles, was uneventful, layering intercurrent infections was noted in 22,2% of vaccine’s, and demonstrated the development of viral respiratory infections, bronchitis, otitis media and exacerbation of underlying disease. It is shown that the level of specific antibody to measles in children with pathology of nervous systems at 30 days after vaccination was 5,04±0,16 log 2, which did not differ from the comparison group (5,88±0,31 log 2). No significant differences in the level of antibody in a smooth and complicated course of vaccination period were found. Immunization of children with disorders of the nervous system of live vaccines is quite effective and leads to the formation of protective antibody titers in all vaccinated.Представлены данные по течению вакцинального процесса и специфическому антителообразованию у 212 детей в возрасте от 1 года до 6 лет, вакцинированных против кори отечественной дивакциной (паротитно-коревой) – 86 детей (40,6%) и монокоревой вакциной – 126 детей (59,4%). Патологию центральной нервной системы имели 170 детей (80,2%), группу сравнения составили 42 практически здоровых ребенка. Поствакцинальный период у детей, иммунизированных против кори, протекал гладко в 77,8% случаев, из них у 84,8% – бессимптомно. Достоверного отличия в течение вакцинального процесса в зависимости от вида вакцины не выявлено. Осложненное течение наблюдалось у 47 (22,2%) привитых, достоверно чаще в группе с неврологической патологией (p&lt;0,05), проявилось ОРВИ, острым бронхитом, отитом, пневмонией, обострением аллергодерматита. Среднегеометрическая величина титров противокоревых антител у детей с патологией ЦНС на 30-й день после вакцинации составила 5,04±0,16log 2, что не отличалось от группы сравнения (5,88±0,31log2). Достоверных различий в уровне антителообразования при гладком и осложненном течении вакцинального периода не выявлено. При использовании дивакцины к 30-му дню вакцинального периода титры антител к кори были достоверно выше, чем при использовании монокоревой вакцины (5,69±0,24 log2 и 4,71±0,21 log2; p&lt;0,05)

SPECIES DIVERSITY OF THE VIR COLLECTION OF GRAIN LEGUME GENETIC RESOURCES AND ITS USE IN DOMESTIC BREEDING

The world’s genebanks hold 7.5 million germplasm accessions of plant genetic resources (PGR). One of the qualitative characteristics of the PGR collections is the species diversity, in particular, the presence of crop wild relatives (CWR), which makes it possible to widen the use of gene pools in the breeding process. The collection of the Vavilov Institute (VIR) is one of the most diverse holdings in the number of plant species. A survey is provided here of the species diversity in VIR’s grain legume collection, and its use in domestic breeding practice is analyzed. Comparison of this diversity with the state of PGR exploitation in the world makes it possible to assess the prospects of more efficient utilization of gene pool potential, especially for species that are unjustifiably cultivated on a too small scale or even neglected as crops in this country. The VIR collection of grain legumes incorporates 196 species from 9 genera of the family Fabaceae. This number includes cultigens and CWR. The cultivars of 21 species of grain legumes listed in the State Register of Breeding Achievements (2018) are adapted to the soil and climate conditions of this country. However, the species diversity of the collection could be used more efficiently in domestic plant breeding and crop production. This concerns both underutilized crops in Russia (broad beans, lima beans and grass pea) and those whose adaptive potential is adjusted only to certain and limited areas of the Russian Federation (Tepary beans and Vigna spp.). It is also necessary to exploit more efficiently species of the wild flora, both for direct utilization as pastures, green manure or phytoremediation crops and for introgressive breeding and domestication (Vicia benghalensis L., V. narbonensis L., Lathyrus sylvestris L., Lupinus hartwegii Lindl., etc.). Incorporation of crop wild relatives into the breeding process is promising for crop improvement in a number of aspects: for example, to increase resistance to diseases, pests, abiotic stressors, etc

ОЦЕНКА ЭФФЕКТИВНОСТИ ВНЕДРЕНИЯ НОВОГО КЛИНИКО-ОРГАНИЗАЦИОННОГО ПОДХОДА К ВТОРИЧНОЙ ПРОФИЛАКТИКЕ АРТЕРИАЛЬНОЙ ГИПЕРТЕНЗИИВ СИСТЕМЕ ПЕРВИЧНОЙ МЕДИКО-САНИТАРНОЙ ПОМОЩИ

The purpose. We aimed to develop, implement and evaluate the efficiency of a novel clinical and organization approach to the medical prevention of cardiovascular diseases in primary health care settings.Material and methods. The comparative assessment of the results of dispensary observation of patients with AH was conducted in the main group (n=308) who underwent a novel prevention program and in the control group (n=240) who were under the usual supervision of a general practitioner. The mean age of the patients in the groups was 59.0±10.8 and 57.5±10.47 years respectively. The basis of the novel prevention technology is the assessment of cardiovascular risk and the development of patients’ itinerary at the pre-hospital stage using the medical information system. Results. In the group with AH who underwent a novel prevention program, a number of patients who had achieved the target systolic and diastolic blood pressure and target cholesterol level was significantly higher than in the control group. The patients of the main group visited a hospital for AH decompensation significantly less frequent. The patients in the main group were more compliant with diagnostic tests and consultations of the specialists as compared to the patients in the control group. The patients of the main group more often attended the classes of the School of Health included into the prevention program. The duration of the observation period was 12±6.5 months.Conclusion. The study proved that the individual prevention program at the pre-hospital stage reduced the prevalence and the severity degree of cardiovascular risk factors and increased the number of patients who had reached the target values of the controlled risk factors after 12±6.5 months of observation. It is achieved by the compliance with requirements of the Russian guidelines and the higher adherence of patients to the preventive measures.Цель. Оценка эффективности нового клинико-организационного подхода к медицинской профилактике артериальной гипертензии (АГ) в первичном звене здравоохранения.Материалы и методы. Проведена сравнительная оценка результатов диспансерного наблюдения группы пациентов с АГ в количестве 308 человек (основная группа), получивших наблюдение по новой технологии медицинской профилактики, и 240 пациентов контрольной группы, которые находились под обычным диспансерным наблюдением участкового врача. Средний возраст пациентов в группах составил 59,0±10,8 и 57,5±10,47 лет соответственно. В основе новой технологии профилактики − оценка сердечно-сосудистого риска и разработка маршрута пациента на доврачебном этапе с применением медицинской информационной системы.Результаты. В группе пациентов с АГ, получивших наблюдение по новой технологии медицинской профилактики, достоверно чаще отмечалось достижение целевого уровня систолического артериального давления (САД) и диастолического артериального давления (ДАД), целевого уровня холестерина (ХС), чем в контрольной группе. Статистически значимо ниже было количество обращений в поликлинику с декомпенсацией АГ. В основной группе исследования отмечался более высокий процент исполнения диагностических исследований и консультаций специалистов в сравнении с контрольной. Пациенты основной группы чаще посещали занятия Школы здоровья, включенные в профилактическую программу. Продолжительность наблюдения 12±6,5 месяцев.Заключение. В исследовании доказано, что назначение индивидуальной программы профилактических мероприятий на доврачебном этапе через 12±6,5 месяцев наблюдения снижает распространенность и степень выраженности факторов риска сердечно-сосудистых заболеваний, повышает долю пациентов, достигших целевых значений управляемых факторов риска. Это достигается за счет соблюдения требований российских рекомендаций и большей приверженности пациентов к профилактическим мероприятиям

Tobacco smoking-associated genome-wide DNA methylation changes in the EPIC study.

Epigenetic changes may occur in response to environmental stressors, and an altered epigenome pattern may represent a stable signature of environmental exposure