Synthesis and Characterization of Large Stereoregular Organosiloxane Cycles

The large stereoregular phenyltrimethylsiloxysiloxane macrocycles of general formula [PhSi(OSiMe3)O]n (n=6 and 12) have been selectively obtained with high yields by trimethylsilylation of cage-like oligophenylmetallasiloxanes (OPMS) which we described earlier. The compounds 3 (n=6) and 4 (n=12) have been characterized by NMR-spectroscopy method and by single crystal X-ray analysis. This investigation showed unambiguously that the siloxane macrocycles keep their size and configuration (the same as in the initial OPMS) during the trimethylsilylation. Thus a synthetic route for obtaining large stereoregular siloxane macrocycles has been developed

Atomic and electronic structure of nanostructured few-layer graphene with self-aligned boundaries synthesized on SiC/Si(001) wafers

This work was partially supported by the Russian Academy of Sciences, Russian Foundation for Basic Research (grant № 17-02-01139, 17-02-01291), Beijing Institute of Technology Research Fund Program for Young Scholars, and Science Foundation Ireland

Systematic study of niobium thermal treatments for superconducting radio frequency cavities employing x ray photoelectron spectroscopy

The structural and chemical composition of the surface layer 100 140 nm of niobium radiofrequency cavities operating at cryogenic temperature has enormous impact on their superconducting characteristics. During the last years, cavities treated with a new thermal processing recipe, so called nitrogen infusion, have demonstrated an increased efficiency and high accelerating gradients. The role and importance of nitrogen gas has been a topic of many debates. In the present work we employ variable energy synchrotron x ray photoelectron spectroscopy XPS , to study the niobium surface subjected to the following treatments vacuum annealing at 800 C, nitrogen infusion, and vacuum heat treatment as for the infusion process but without nitrogen supply. Careful analysis of XPS energy distribution curves revealed a slightly increased thickness of the native oxide Nb2O5 for the infused samples amp; 8764;3.8 nm as compared to the annealed one amp; 8764;3.5 nm which indicates insignificant oxygen incorporation into niobium during 120 C baking and no effect of nitrogen on the formation of oxides or other niobium phases. By conducting an additional in situ annealing experiment and analyzing the niobium after the failed infusion process, we conclude that the vacuum furnace hygiene particularly during the high temperature stage is the prerequisite for success of any treatment recip

A photochemical approach for a fast and self-limited covalent modification of surface supported graphene with photoactive dyes

Herein, we report a simple method for a covalent modification of surface supported graphene with photoactive dyes. Graphene was fabricated on cubic-SiC/Si(001) wafers due to their low cost and suitability for mass-production of continuous graphene fit for electronic applications on millimetre scale. Functionalisation of the graphene surface was carried out in solution via white light induced photochemical generation of phenazine radicals from phenazine diazonium salt. The resulting covalently bonded phenazine-graphene hybrid structure was characterised by scanning tunnelling microscopy (STM) and spectroscopy (STS), Raman spectroscopy and density functional theory (DFT) calculations. It was found that phenazine molecules form an overlayer, which exhibit a short range order with a rectangular unit cell on the graphene surface. DFT calculations based on STM results reveal that molecules are standing up in the overlayer with the maximum coverage of 0.25 molecules per graphene unit cell. Raman spectroscopy and STM results show that the growth is limited to one monolayer of standing molecules. STS reveals that the phenazine-graphene hybrid structure has a band gap of 0.8 eV

Vaginal infections in patients of childbearing age: ways for optimization of treatment in the outpatient setting

Despite the considerable success in managing the medical process and medical screening of women of childbearing age, the treatment of vaginal infection remains an urgent problem that requires periodic correction of the prescribed therapy. This made the authors conduct a study, which was aimed at investigating the optimization aspects of the comprehensive therapy regimens for vaginal infections (VI) that combine the use of etiotropic drugs with the extract of Aloe Barbadenis Multi-Gyn ActiGel and systemic enzyme therapy as compared to the prescription of monotherapeutic etiotropic regimen. The study evaluated the effectiveness of different treatment regimens of VIs based on the dynamics of clinical and laboratory parameters, as well as the safety and tolerability of different therapies based on the registration of adverse events.Based on the study results, we would advise to include the plant extract of Aloe Barbadenis Multi-Gyn ActiGel and Wobenzym into the therapy of patients with VIs induced by the  vaginal dysbiosis and caused by bacterial vaginosis and candidiasis vulvovaginitis-associated microorganisms to improve the elimination of the pathogen and provide a normal titre of lactobacilli with preservation of their functional activity, which eventually restores the impaired vaginal microcenosis and maintains a normal vaginal flora and simultaneously provides a high safety and good tolerability of the proposed treatment regimen

Systematic study of niobium thermal treatments for superconducting radio frequency cavities employing x-ray photoelectron spectroscopy

The structural and chemical composition of the surface layer (100–140 nm) of niobium radiofrequency cavities operating at cryogenic temperature has enormous impact on their superconducting characteristics. During the last years, cavities treated with a new thermal processing recipe, so-called nitrogen infusion, have demonstrated an increased efficiency and high accelerating gradients. The role and importance of nitrogen gas has been a topic of many debates. In the present work we employ variable-energy synchrotron x-ray photoelectron spectroscopy (XPS), to study the niobium surface subjected to the following treatments: vacuum annealing at 800 °C, nitrogen infusion, and vacuum heat treatment as for the infusion process but without nitrogen supply. Careful analysis of XPS energy-distribution curves revealed a slightly increased thickness of the native oxide Nb2O5 for the infused samples (∼3.8 nm) as compared to the annealed one (∼3.5 nm) which indicates insignificant oxygen incorporation into niobium during 120 °C baking and no effect of nitrogen on the formation of oxides or other niobium phases. By conducting an additional in-situ annealing experiment and analyzing the niobium after the failed infusion process, we conclude that the vacuum furnace hygiene particularly during the high-temperature stage is the prerequisite for success of any treatment recipe

Association of inflammatory markers and poor outcome in diabetic patients presenting with ST segment elevation myocardial infarction

Yulia Belenkova,1,2 Viktoria Karetnikova,1,2 Aleksey Diachenko,2 Olga Gruzdeva,1 Olga Blagoveshchenskaya,3 Tatiana Molodtsova,3 Evgenya Uchasova,1 Olga Barbarash1,2 1Federal State Budgetary Institution Research Institute for Complex Issues of Cardiovascular Diseases, Siberian Branch of the Russian Academy of Medical Sciences, 2State Budgetary Educational Institution of Higher Professional Education Kemerovo State Medical Academy of the Russian Ministry of Health, 3State Budgetary Healthcare Institution Kemerovo Regional Clinical Hospital, Kemerovo, Russian Federation Objective: Carbohydrate metabolism disorders (CMD) significantly impact the development and progression of all forms of ischemic heart disease, and inflammation is regarded as a general pathogenetic link between CMD and ischemic heart disease. Methods: A total of 601 patients with ST segment elevation myocardial infarction (MI) (STEMI), admitted within 24 hours from the onset of symptoms during 1 year, were included in this registry study. The blood levels of inflammation markers were measured at days 10–14 with further follow up at 1 year. Results: The analysis of acute-phase percutaneous coronary intervention impact on the 1-year outcomes showed that endovascular revascularization significantly improved the 1-year prognosis of STEMI patients both with and without CMD. The analysis of inflammation markers showed significantly higher levels of interleukin (IL)-6 and sCD40L in MI patients with diabetes mellitus, and impaired glucose tolerance. Additionally, the patients with impaired glucose tolerance had significantly higher IL-12 levels. In the diabetic MI patients, the odds ratio of a poor 1-year outcome was high for patients with a high Killip classification of acute heart failure upon admission. Conclusion: Persistent inflammation in STEMI patients with CMD undergoing percutaneous coronary intervention might be responsible for vascular complications within 1 year after MI. Comorbid diabetes mellitus or impaired glucose tolerance can amplify the significance of the inflammatory response for the development of adverse 1-year outcomes. Keywords: carbohydrate metabolism disorders, inflammation percutaneous coronary intervention&nbsp