Дослідження структурних особливостей взаємодії S-протеїну SARS-CoV-2 з ліпідними мембранами методом малокутового розсіяння нейтронів

The effect of SARS-CoV-2 coronavirus S-protein on the structural parameters of the model lipid membrane on dimyristoylphosphatidylcholine (DMPC) systems with cholesterol and melatonin impurities was studied by the method of small angle neutron scattering. It is shown that an increase in the concentration of melatonin in the lipid membrane leads to a decrease in the thickness of the lipid bilayer, and an increase in the concentration of cholesterol leads to an increase in it. It has been suggested that increasing the concentration of melatonin in the membrane prevents the interaction of coronaviral S-protein with the lipid membrane of the cell. In the presence of cholesterol impurities in the system, the interaction of the lipid membrane with the active part of the S-protein occurs depending on the phase state of the lipid. Thus, when the lipid is in the gel phase (at 10 ° C), the active part of the S-protein does not change the structural parameters of the lipid bilayer, i.e. the interaction between the lipid membrane and the active part of the S-protein does not occur. At 37 ° C, when the lipid is in the liquid crystalline phase, the addition of RBD SARS-CoV-2 in the system DMPC / 30% Cholesterol / D2O leads to a decrease in membrane thickness, indicating the interaction of S-protein with the membrane. Pages of the article in the issue: 127 - 130 Language of the article: UkrainianМетодом малокутового розсіяння нейтронів проведено дослідження впливу S-протеїну коронавірусу SARS-CoV-2 на структурні параметри модельної ліпідної мембрани на системах диміристоїлфосфатидилхоліну (ДМФХ) з домішками холестерину та мелатоніну. Висунуто припущення, що збільшення концентрації мелатоніну в мембрані запобігає взаємодії коронавірусного S-протеїну з ліпідною мембраною клітини. За присутності домішок холестерину в системі взаємодія ліпідної мембрани з активною частиною S-протеїну відбувається залежно від фазового стану ліпіду: у випадку гель-фази взаємодія не відбувається, а у рідкокристалічній фазі додавання RBD SARS-CoV-2 в систему призводить до зменшення товщини мембрани

Verificação do apoio gerencial da trajetória profissional e educacional dos alunos no ambiente educacional sociocultural da universidade

The relevance of the study is determined by the processes of modernization of vocational education and the transition to the educational standards of the third generation, which open up new opportunities for students and teachers. Step-by-step management support of professional and educational trajectory of students requires organizational conditions and the development of technology for its practical implementation. Identifying the level of motivation in students when choosing a future profession allows assessing the level of inclusion of students in educational and cognitive activities and determining how far it is from the optimal motivational level, which allows the student achieving their goals, advancing in professional and personal development. At the initial stage of diagnosis, the analysis of professional experience of students, successes and problems in the training practice of the first year of training is carried out, at the next stage, the results of research activities on the results of the second year of training are analyzed. Activity-practical criterion, indicators of which are formed professional skills, primary professional experience, being in a sense the total overall performance indicator of professional and personal development of students, also changes qualitatively in the direction of improvement.La relevancia del estudio está determinada por los procesos de modernización de la educación vocacional y la transición a los estándares educativos de la tercera generación, que abren nuevas oportunidades para estudiantes y profesores. El apoyo paso a paso de la gestión de la trayectoria profesional y educativa de los estudiantes requiere condiciones organizativas y el desarrollo de tecnología para su implementación práctica. Identificar el nivel de motivación en los estudiantes al elegir una profesión futura permite evaluar el nivel de inclusión de los estudiantes en actividades educativas y cognitivas y determinar qué tan lejos está del nivel motivacional óptimo, lo que permite al estudiante alcanzar sus metas, avanzando en lo profesional y en el desarrollo peronal. En la etapa inicial del diagnóstico, el análisis de la experiencia profesional de los estudiantes, los éxitos y los problemas en la práctica de capacitación del primer año se lleva a cabo. En la siguiente etapa, se analizan los resultados de las actividades de investigación sobre los resultados del segundo año de capacitación. El criterio práctico de la actividad, cuyos indicadores son habilidades profesionales formadas, experiencia profesional primaria, siendo en cierto sentido el indicador de rendimiento global total del desarrollo profesional y personal de los estudiantes, también cambia cualitativamente en la dirección de la mejora.A relevância do estudo é determinada pelos processos de modernização do ensino profissional e pela transição para os padrões educacionais da terceira geração, que abrem novas oportunidades para alunos e professores. O apoio passo a passo da gestão da trajetória profissional e educacional dos alunos requer condições organizacionais e o desenvolvimento de tecnologia para sua implementação prática. Identificar o nível de motivação dos alunos na escolha de uma profissão futura para avaliar o nível de inclusão de alunos em actividades educativas e cognitivas e determinar o quão longe é o nível motivacional ideal, que permite que o aluno a alcançar seus objetivos, o progresso na profissional e no desenvolvimento peronal. Na fase inicial do diagnóstico, ocorre a análise da experiência profissional dos alunos, sucessos e problemas na prática do primeiro ano de treinamento. Na etapa seguinte, são analisados os resultados das atividades de pesquisa sobre os resultados do segundo ano de treinamento. O critério prático da atividade, cujos indicadores são habilidades profissionais treinadas, experiência profissional primária, sendo de certa forma o indicador do desempenho global total do desenvolvimento profissional e pessoal dos estudantes, também muda qualitativamente na direção da melhoria

Impact of uniaxial strain and doping on oxygen diffusion in CeO2

Doped ceria is an important electrolyte for solid oxide fuel cell applications. Molecular dynamics simulations have been used to investigate the impact of uniaxial strain along the directions and rare-earth doping (Yb, Er, Ho, Dy, Gd, Sm, Nd, and La) on oxygen diffusion. We introduce a new potential model that is able to describe the thermal expansion and elastic properties of ceria to give excellent agreement with experimental data. We calculate the activation energy of oxygen migration in the temperature range 900-1900K for both unstrained and rare-earth doped ceria systems under tensile strain. Uniaxial strain has a considerable effect in lowering the activation energies of oxygen migration. A more pronounced increase in oxygen diffusivities is predicted at the lower end of the temperature range for all the dopants considered

Quaternary Selenides EuLnCuSe3: Synthesis, Structures, Properties and In Silico Studies

In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu+2Ln+3Cu+1Se3 composition. Crystal structures of the obtained compounds were refined by the derivative difference minimization (DDM) method from the powder X-ray diffraction data. The structures are found to belong to orthorhombic space groups Pnma (structure type Ba2MnS3 for EuLaCuSe3 and structure type Eu2CuS3 for EuLnCuSe3, where Ln = Sm, Gd, Tb, Dy, Ho and Y) and Cmcm (structure type KZrCuS3 for EuLnCuSe3, where Ln = Tm, Yb and Lu). Space groups Pnma and Cmcm were delimited based on the tolerance factor t’, and vibrational spectroscopy additionally confirmed the formation of three structural types. With a decrease in the ionic radius of Ln3+ in the reported structures, the distortion of the (LnCuSe3) layers decreases, and a gradual formation of the more symmetric structure occurs in the sequence Ba2MnS3 → Eu2CuS3 → KZrCuS3. According to magnetic studies, compounds EuLnCuSe3 (Ln = Tb, Dy, Ho and Tm) each exhibit ferrimagnetic properties with transition temperatures ranging from 4.7 to 6.3 K. A negative magnetization effect is observed for compound EuHoCuSe3 at temperatures below 4.8 K. The magnetic properties of the discussed selenides and isostructural sulfides were compared. The direct optical band gaps for EuLnCuSe3, subtracted from the corresponding diffuse reflectance spectra, were found to be 1.87– 2.09 eV. Deviation between experimental and calculated band gaps is ascribed to lower d states of Eu2+ in the crystal field of EuLnCuSe3, while anomalous narrowing of the band gap of EuYbCuSe3 is explained by the low-lying charge-transfer state. Ab initio calculations of the crystal structures, elastic properties and phonon spectra of the reported compounds were performed. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding: The research was supported by the Tyumen region within the framework of the grant agreement in the form of a grant to non-profit organizations no. 89-don dated 07.12.2020. This study was supported by the Ministry of Science and Higher Education of the Russian Federation (project no. FEUZ-2020-0054). This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 720000Ф.99.1.БЗ85АА13000). The work was conducted within the framework of the budget project № 0287-2021-0013 for the Institute of Chemistry and Chemical Technology SB RAS

From where did the 2009 'swine-origin' influenza A virus (H1N1) emerge?

The swine-origin influenza A (H1N1) virus that appeared in 2009 and was first found in human beings in Mexico, is a reassortant with at least three parents. Six of the genes are closest in sequence to those of H1N2 'triple-reassortant' influenza viruses isolated from pigs in North America around 1999-2000. Its other two genes are from different Eurasian 'avian-like' viruses of pigs; the NA gene is closest to H1N1 viruses isolated in Europe in 1991-1993, and the MP gene is closest to H3N2 viruses isolated in Asia in 1999-2000. The sequences of these genes do not directly reveal the immediate source of the virus as the closest were from isolates collected more than a decade before the human pandemic started. The three parents of the virus may have been assembled in one place by natural means, such as by migrating birds, however the consistent link with pig viruses suggests that human activity was involved. We discuss a published suggestion that unsampled pig herds, the intercontinental live pig trade, together with porous quarantine barriers, generated the reassortant. We contrast that suggestion with the possibility that laboratory errors involving the sharing of virus isolates and cultured cells, or perhaps vaccine production, may have been involved. Gene sequences from isolates that bridge the time and phylogenetic gap between the new virus and its parents will distinguish between these possibilities, and we suggest where they should be sought. It is important that the source of the new virus be found if we wish to avoid future pandemics rather than just trying to minimize the consequences after they have emerged. Influenza virus is a very significant zoonotic pathogen. Public confidence in influenza research, and the agribusinesses that are based on influenza's many hosts, has been eroded by several recent events involving the virus. Measures that might restore confidence include establishing a unified international administrative framework coordinating surveillance, research and commercial work with this virus, and maintaining a registry of all influenza isolates

Применение удобрений пролонгированного действия при выращивании рассады земляники садовой

Timeliness. Currently, the Russian Federation has a high demand in healthy planting material of garden strawberries. The benefits of using fertilizers when growing strawberry seedlings have been proven by numerous studies. However, a comparative study of the effect of new fertilizers and methods of their application is very limited. In this regard, studies aimed at identifying the effectiveness of the use of prolonged-acting fertilizers in the production of garden strawberry planting material in protected soil conditions are relevant.Methods. Adapted to non-sterile conditions, ex vitro healthy garden strawberry plants were planted in a peat substrate of Veltorf LLC (recipe No. 5c/2) with the addition of Pg mix starter fertilizer with the structure NPK 14-16-18 + microelements (1.5 g/l of substrate). At the same time, prolonged-acting fertilizers were introduced into the substrate in the recommended concentrations: FertiPro Gran 1M (1.25 g/l of substrate), Ruscote 5-6M (3.0 g/l of substrate), Basacote Plus 6M (4.0 g/l of substrate), control peat substrate without fertilizers, PG mix standard.Results. It has been established that for the Karmen crop with an average runner-forming ability, the effectiveness of applying FertiPro Gran 1M fertilizer to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 3.5–3.8 times compared to the control. At the same time, the yield of marketable seedlings is 95% compared to 70% in the control. For the Jūnija smaids crop with a high vine-forming ability, the effectiveness of all experimental variants with the application of FertiPro Gran 1M, Ruscote and Basacote Plus fertilizers to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 1,9-2,5 times compared to the control. At the same time, the yield of marketable seedlings is 94-96% compared to 65% in the control.Conclusion. The introduction of long–acting fertilizers FertiPro Gran, Ruscote and Basacote Plus into the peat substrate with the addition of Pg mix starter fertilizer allowed a 2.3 – 3.8-fold increase in the number of runners obtained and 1.9-3.5-fold increase in the number of sockets obtained compared to the control without fertilizers. Актуальность. В настоящее время в Российской Федерации существует высокая потребность в оздоровленном посадочном материале земляники садовой. Преимущество применения удобрений при выращивании рассады земляники были доказаны многочисленными исследованиями. Однако сравнительное изучение действия влияния новых удобрений и методов их применения очень ограничено. В связи с этим, исследования направленные на выявление эффективности использования удобрений пролонгированного действия при производстве посадочного материала земляники садовой в условиях защищенного грунта являются актуальными.Методы. Адаптированные к нестерильным условиям оздоровленные еx vitro растения земляники садовой высаживали в торфяной субстрат компании ООО Велторф (рецепт № 5с/2) с добавлением стартового удобрения Pg mix со структурой NPK 14-16- 18 – микроэлементы (1,5 г/л субстрата). При этом в состав субстрата вводили удобрения пролонгированного действия в рекомендованных концентрациях FertiPro Gran 1М (1,25 г/л субстрата), Ruscote 5-6М (3,0 г/л субстрата), Basacote Plus 6М (4,0 г/л субстрата), контроль торфяной субстрат без удобрений, эталон PG mix.Результаты. Установлено, что для сорта Karmen со средней усообразовательной способностью выявлена эффективность внесения в субстрат удобрения FertiPro Gran 1М, при применении которого на 180 сутки выращивания в 3,5-3,8 раз увеличивается количество усов и розеток по сравнению с контролем и при этом выход товарной рассады составляет 95 % по сравнению с 70% в контроле. Для сорта Jūnija smaids с высокой усообразовательной способностью выявлена эффективность всех опытных вариантов с внесением в субстрат удобрений FertiPro Gran 1М, Ruscote и Basacote Plus при применении которых на 180 сутки выращивания в 1,9-2,5 раза увеличивается количество усов и розеток по сравнению с контролем и при этом выход товарной рассады составляет 94-96% по сравнению с 65% в контроле.Заключение. Внесение удобрений пролонгированного действия FertiPro Gran, Ruscote и Basacote Plus в торфяной субстрат с добавлением стартового удобрения Pg mix позволило 2,3-3,8 раз увеличить количество полученных усов и в 1,9- 3,5 раз полученных розеток по сравнению с контролем без удобрений.

Симультанное хирургическое лечение больных почечно-клеточным раком с конкурирующей патологией сердца

The authors analyze the immediate results of 8 simultaneous operations, 4 of these under conditions of artificial circulation, in patients with renal cell carcinoma concomitant with heart diseases. The immediate results were satisfactory, with good functional parameters. Due to simultaneous operations the incidence of intra- and postoperative cardiovascular complications is reduced, the progress of the tumor process between different stages of treatment is arrested, early radical interventions for tumor removal becomes possible, and the hospitalization period is shorter in comparison with staged operations.

Ab initio studies of structures and properties of small potassium clusters

We have studied the structure and properties of potassium clusters containing even number of atoms ranging from 2 to 20 at the ab initio level. The geometry optimization calculations are performed using all-electron density functional theory with gradient corrected exchange-correlation functional. Using these optimized geometries we investigate the evolution of binding energy, ionization potential, and static polarizability with the increasing size of the clusters. The polarizabilities are calculated by employing Moller-Plesset perturbation theory and time dependent density functional theory. The polarizabilities of dimer and tetramer are also calculated by employing large basis set coupled cluster theory with single and double excitations and perturbative triple excitations. The time dependent density functional theory calculations of polarizabilities are carried out with two different exchange-correlation potentials: (i) an asymptotically correct model potential and (ii) within the local density approximation. A systematic comparison with the other available theoretical and experimental data for various properties of small potassium clusters mentioned above has been performed. These comparisons reveal that both the binding energy and the ionization potential obtained with gradient corrected potential match quite well with the already published data. Similarly, the polarizabilities obtained with Moller-Plesset perturbation theory and with model potential are quite close to each other and also close to experimental data.Comment: 33 pages including 10 figure

Extended Thromboprophylaxis with Betrixaban in Acutely Ill Medical Patients

Background Patients with acute medical illnesses are at prolonged risk for venous thrombosis. However, the appropriate duration of thromboprophylaxis remains unknown. Methods Patients who were hospitalized for acute medical illnesses were randomly assigned to receive subcutaneous enoxaparin (at a dose of 40 mg once daily) for 10±4 days plus oral betrixaban placebo for 35 to 42 days or subcutaneous enoxaparin placebo for 10±4 days plus oral betrixaban (at a dose of 80 mg once daily) for 35 to 42 days. We performed sequential analyses in three prespecified, progressively inclusive cohorts: patients with an elevated d-dimer level (cohort 1), patients with an elevated d-dimer level or an age of at least 75 years (cohort 2), and all the enrolled patients (overall population cohort). The statistical analysis plan specified that if the between-group difference in any analysis in this sequence was not significant, the other analyses would be considered exploratory. The primary efficacy outcome was a composite of asymptomatic proximal deep-vein thrombosis and symptomatic venous thromboembolism. The principal safety outcome was major bleeding. Results A total of 7513 patients underwent randomization. In cohort 1, the primary efficacy outcome occurred in 6.9% of patients receiving betrixaban and 8.5% receiving enoxaparin (relative risk in the betrixaban group, 0.81; 95% confidence interval [CI], 0.65 to 1.00; P=0.054). The rates were 5.6% and 7.1%, respectively (relative risk, 0.80; 95% CI, 0.66 to 0.98; P=0.03) in cohort 2 and 5.3% and 7.0% (relative risk, 0.76; 95% CI, 0.63 to 0.92; P=0.006) in the overall population. (The last two analyses were considered to be exploratory owing to the result in cohort 1.) In the overall population, major bleeding occurred in 0.7% of the betrixaban group and 0.6% of the enoxaparin group (relative risk, 1.19; 95% CI, 0.67 to 2.12; P=0.55). Conclusions Among acutely ill medical patients with an elevated d-dimer level, there was no significant difference between extended-duration betrixaban and a standard regimen of enoxaparin in the prespecified primary efficacy outcome. However, prespecified exploratory analyses provided evidence suggesting a benefit for betrixaban in the two larger cohorts. (Funded by Portola Pharmaceuticals; APEX ClinicalTrials.gov number, NCT01583218. opens in new tab.