Novel mechanism for temperature-independent transitions in flexible molecules: role of thermodynamic fluctuations

Novel physical mechanism is proposed for explanation of temperature-independent transition reactions in molecular systems. The mechanism becomes effective in the case of conformation transitions between quasi-isoenergetic molecular states. It is shown that at room temperatures, stochastic broadening of molecular energy levels predominates the energy of low frequency vibrations accompanying the transition. This leads to a cancellation of temperature dependence in the stochastically averaged rate constants. As an example, physical interpretation of temperature-independent onset of P2X_3 receptor desensitization in neuronal membranes is provided.Comment: 4 pages, 1 figur

Electron spin resonance study on Mo-SiO₂ and Mo-TiO₂ with adsorbed benzene

The study is devoted to ESR-investigation of the primary processes upon chemisorption of benzene molecules onto the molybdenum supported on dispersed SiO₂ and TiO₂ samples. It has been confirmed that benzene chemisorption onto the Mo⁶⁺ species results in one-electron transfer in the ground state and paramagnetic species formation, namely reduced molybdenum species (Mo⁵⁺ species) and radicals of benzene. Computer treatment of ESR experimental data revealed that there are several types of Mo⁵⁺ species and benzene radicals, the assignment of which is proposed

Towards Time - Dynamics for Bosonic Systems in Quantum Statistical Mechanics

Consider a one-dimensional lattice boson system with the Hamiltonian in a finite box Λ, H_Λ = K_Λ + U_Λ. Here K_Λ is the kinetic energy and U_Λ is the potential energy corresponding to a finite-range pair interaction. For a class of states T of the infinite system, we prove the existence of the limit T_t(A) = lim_(Λ→Z) T(e^(itH_Λ)*Ae^(-itH_Λ)) for any t ϵ R^4 and any local observable A. Thereby a family {T_t, t ϵ R^4} of locally normal states is determined which describes the time-evolution of the initial state T

Экспериментальные исследования формирования акустической волны электромагнитно-акустическим преобразователем

В статті розглянуті результати експериментальних досліджень формування акустичної хвилі електромагнітно-акустичним ЕМА перетворювачем із гребінчастим методом збудження, виходячи з параметрів, які впливають на формування акустичної хвилі. Досліджено можливість введення ультразвукової хвилі за допомогою системи паралельно розташованих ниток-випромінювачів. Проведено експериментальні дослідження формування акустичної хвилі ЕМА перетворювачем, отримані експериментальні дані по зміні вихідного сигналу залежно від величини зазору між випромінювачем і поверхнею об'єкта контролю й сили струму через нитки-випромінювачі. Показано гарну збіжність результатів теоретичних і експериментальних досліджень.The article touches upon the results of experimental researches of acoustic wave formation by electromagnetic-acoustic EMA transducer with pectinate method of excitation based on the parameters that influence on the formation of acoustic wave. The ability of introducing ultrasound waves through a system of parallel arranged filament emitters is investigated. The Experimental researches of acoustic wave formation by electromagnetic-acoustic EMA transducer are made, the experimental data about the change of the output signal depending on the size of the gap between the emitter and the surface of the object of control and current strength through the filament emitters are received. A good results’ convergence of theoretical and experimental researches is demonstrated.В статье рассмотрены результаты экспериментальных исследований формирования акустической волны электромагнитно-акустическим ЭМА преобразователем с гребенчатым методом возбуждения, исходя из параметров, которые влияют на формирование акустической волны. Исследована возможность введения ультразвуковой волны с помощью системы параллельно расположенных нитей-излучателей. Проведены экспериментальные исследования формирования акустической волны ЭМА преобразователем, полученные экспериментальные данные по изменению выходного сигнала в зависимости от величины зазора между излучателем и поверхностью объекта контроля и силы тока через нити-излучатели. Показано хорошую сходимость результатов теоретических и экспериментальных исследований

Features of diagnostics of gastroesophageal and duodenogastric reflux in patients with complicated forms of peptic ulcer.

Purpose – to improve the results of surgical treatment of duodenal ulcer due to preoperative diagnosis of concomitant reflux disease and its correction. Before surgery, 46 patients with complicated forms of peptic  ulcer disease underwent pH monitoring and 23 – impedance-pH monitoring. Pathological gastroesophageal reflux was found in 58 cases. Before surgery, esophageal pH monitoring was performed in 46 patients with complicated forms of peptic ulcer disease. Against the background of hyper – and normacidity of the stomach in 39 patients pathological acidic gastroesophageal reflux disease with a significant increase of De Meester index was confirmed. Impedance-pH monitoring was performed before surgery in 23 patients with complicated forms of peptic ulcer and concomitant gastroesophageal reflux. Erosive form of gastroesophageal reflux disease was confirmed endoscopically in all patients with hyperacidity (17) and normal acidity (6) of the stomach. In 19 cases pathological gastroesophageal reflux disease was found. In 13 cases the cause of disorders in anti-reflux barrier was a diaphragmatic hernia of I-II degree. Gastroesophageal reflux disease was caused by increased intragastric pressure due to ulcer stenosis in 6 patients. pH- monitoring in patients with acidic gastroesophageal reflux allows to establish a pathological or physiological reflux. Conducting impedance-pH monitoring allows to determine the number of reflux episodes and their qualitative characteristics (acidic or alkaline; liquid, gas or mixed), as well as to determine the indications for a differentiated approach in the treatment of gastroesophageal reflux

EPIDEMIOLOGICAL FEATURES OF MELANOMA SKIN CANCER AND SURVIVAL OF ONCOLOGY PATIENTS IN KRASNODAR REGION

Aim. To assess the effectiveness of preventive, diagnostic and therapeutic work of the oncological service of Krasnodar Region, analyze the epidemiological features of morbidity, mortality, indicators reflecting the diagnosis (the proportion of early detection, neglect) in patients with melanoma skin cancer for the period 2007–2017, and the survival of cancer patients in Krasnodar Region for the period 2007–2016.Materials and methods. Subjects of the study were patients with newly diagnosed melanoma skin cancer in Krasnodar Region for the period 2007–2017. Using an automated information and analytical system the Population Cancer Registry, survival of 3 961 patients with melanoma skin cancer for the period 2007–2016 was analyzed. Standardized rates of morbidity and mortality were calculated according to the accepted world standard with the same age groupings. Statistical processing of data according to the studied indicators was carried out using statistical software packages Statistica. The reliability of the difference in the relative indicators was determined by the t test of the Student, the significance level was adopted as p <0.05.Results. For the period from 2007 to 2017, there has been a significant trend towards an increase in the incidence of melanoma skin cancer of the population of Krasnodar Region. The incidence of melanoma skin cancer in Krasnodar Region is higher than the average for the Russian Federation, which may be due to the presence of an increased level of insolation. During the analyzed period there has been a decrease in the indicator of neglect. With the increase in the stage of melanoma skin cancer, the survival rates both in general among all the diseased and among patients of working age are decreasing. The highest rates of observed and adjusted survival in patients with melanoma skin cancer reduce in the first three years from the date of diagnosis. The indicators of the observed and corrected survival of men of working age with melanoma skin cancer are lower than in women of working age. The indicators of the observed and corrected survival of women of working age with melanoma skin cancer are higher than among the population of all age groups.Сonclusion. The study showed a high level of early diagnosis and quality of treatment for patients with melanoma skin cancer in the Krasnodar Region, as positive trends in the rates of observed and adjusted survival of patients were noted

Ce-doped Li6Ln(BO3)3 (Ln = Y, Gd) Single crystals fibers grown by micro-pulling down method and luminescence properties

Ce3+-doped borate crystal fibers of Li6Gd(BO 3)3 (LGBO) and Li6Y(BO3)3 (LYBO) compositions are grown by the micro-pulling down (μ-PD) method for potential application in developing new neutron detectors. The ternary equilibrium diagram of Li2O-Gd2O3-B 2O3 is drawn and the preparations of homogeneous mixed LGBO and LYBO powders and growth conditions for single crystal fibers are discussed. Absorption, excitation and X-ray luminescence spectra are investigated. Absolute light yield derived from energy spectra and kinetic decay curves measured under α- and γ-scintillations of Ce 3+-doped LGBO and LYBO single crystal fibers is provided. © 2012 Elsevier B.V. All rights reserved

Limitations and opportunities of cancer treatment in the COVID-19 pandemic

The COVID-19 pandemic has affected all medical fields and brought up a lot of serious problems. The features of the COVID-19 infection in patients with cancer are important to understand. According to many articles, patients with cancer are more vulnerable to COVID-19 infection. Patients undergoing anticancer treatment have 1-4% morbidity rate. Patients with hematological diseases and lung cancer are at higher risk of SARS-CoV-2 infection and also have more severe symptoms and complications. In this article we discuss the effect of the tumors on the immune system and comprehend the pathogenesis of the coronavirus disease according to its impact on the immunity. Moreover, in the review we analyze available data about the influence of the different types of cancer therapy (chemotherapy, target therapy, radiotherapy and immunotherapy) on the severity of the COVID-19 infection. Evidence on the effect of chemotherapy on severity and mortality from COVID-19 is contradictory. Whereas there are some authors concluding that chemotherapy treatment is not affecting the severity of COVID-19 disease, there are also some works where the connection between these facts was established. At the same time target therapy, radio- and immunotherapy most likely do not worsen the SARS-CoV-2 infection and are not associated with the development of complications. But it’s important to say that the amount of data available for today is insufficient to make a unambiguous conclusion

Antithrombotic therapy in patients with atrial flutter before planned cardioversion

Резюме. Вступ: фібриляція/тріпотіння передсердь (ФП, ТП) - порушення ритму серця, на фоні яких зростає ризик життєнебезпечних ускладнень – кардіоемболічного інсульту, тромбоемболії легеневої артерії. Рекомендації щодо ведення хворих з ФП-ТП, з тривалістю пароксизму понад 48 годин, вимагають антикоагулянтної терапії. З метою периманіпуляційної підготовки пацієнтів з ТП до відновлення синусового ритму (СР) методом черезстравохідної електрокардіостимуляції (ЧСЕКС) використовують пероральні антикоагулянти - антагоністи вітаміну К (варфарин), нові оральні антикоагулянти (ривароксабан). Ціль дослідження: порівняти ефективність та безпечність варфарину та ривароксабану у хворих з ТП перед проведенням планової кардіоверсії методом ЧСЕКС. Матеріали та методи: 42 хворим на ішемічну хворобу серця з супутньою артеріальною гіпертензією та пароксизмом ТП неклапанної етіології тривалістю >48 год, розділеним на 2 групи, призначали варфарин (КГ), в еквівалентних для досягнення цільового МНВ дозах, або ривароксабан (ДГ) 20 мг. Проводили загальноклінічне, ехокардіоскопічне (ЕхоКС) обстеження. Тромботичний ризик оцінювали за шкалою CHA2DS2-VASc, геморагічний ризик - за шкалою HAS-BLED, клінічну симптоматику - за шкалою EHRA. Ритм відновлювали ЧСЕКС. Результати: у пацієнтів ДГ , на відміну від пацієнтів КГ (термін з підбором цільового МНВ складав 30,76±0,62 днів), спостерігалось скорочення терміну підготовки (згідно рекомендацій 21 день), у динаміці спостерігалося зменшення вираженості симптомів за EHRA. За результатами ЧСЕКС у хворих ДГ відновлено СР у 15 хворих, у 6 хворих переведено в ФП. У хворих КГ, СР - відновлено у 6 хворих, у 10 хворих - ФП. Висновок: застосування ривароксабану з метою периманіпуляційної підготовки до планової кардіоверсії шляхом ЧСЕКС призводить до скорочення термінів підготовки, зменшує ризик розвитку проявів серцевої недостатності, сприяє відновленню СР у пацієнтів з ТП. Abstract. Introduction: atrium flutter and fibrillation are the heart rhythm disorders that increase the risk of life-dangerous complications, e.g. cardioembolic stroke, pulmonary embolism. Recommendations for managing patients with atrial fibrillation – atrial flutter, with paroxysm duration over 48 hours, demand anticoagulant therapy. Oral anticoagulants, which are the antagonists of K vitamin (Varpharin) and the new oral anticoagulants (Rivaroxaban), are used during the per-manipulative procedure of patients with atrial flutter before restoring the sinus rhythm with transesophageal cardiac pacing. Aim: the present investigation aims to compare efficiency and safety of Varpharin and Rivaaroxaban in treatment patients with atrial flutter before planned cardioversion with transesophageal heart pacing. Materials and methods: Varpharin (control group) – in doses equivalent for reaching the target МНВ – or Rivaroxaban (research group), 20 mg., were prescribed to 42 patients with coronary heart disease, concomitant arterial hypertension, and non-valvular paroxysm of atrial flutter with more than 48-hour duration, divided into two groups. There was held the general clinical, echocardioscopy examination. Thrombotic Risk Factor Assessment was made according to the CHA2DS2-VASc scale, Hemorrhagic Risk Factor Assessment was performed according to the HAS-BLED scale, and clinical symptoms assessment was made according to the EHRA scale. The heart rhythm was restored with the transesophageal heart pacing. Results: the per-manipulative procedure of the patients of research group (21 days were suggested according to the guidelines) shortened, unlike the patients of control group (the period of target МНВ selection had made 30,76±0,62days), the reduction of the symptoms severity by EHRA was considered in dynamics. According to the results of transesophageal heart pacing, the heart rhythm of 15 research group patients restored, and 6 research group patients had atrial fibrillation. Among the patients of the control group, 6 had their heart rhythm restored, as 10 patients had the atrial fibrillation. Conclusions: the use of Rivaroxaban during the per-manipulative procedure before planned cardioversion with transesophageal heart pacing causes shortening of the per-manipulative period, reduces the risk of development of symptoms of heart failure, helps to restore the heart rhythm of the patients with atrium flutter

Model of demand for labor in the urfo pharmaceutical market

The purpose of the study is to comprehensive assessment of the structure of demand for labor in the pharmaceutical market of the URFO to build empirical functions of the demand for labor resources for pharmaceutical specialists with different qualifications.Цель исследования – комплексная оценка структуры спроса на труд на фармацевтическом рынке УрФО для построения эмпирических функций спроса на трудовые ресурсы для фармацевтических специалистов с разной квалификацией