Peculiarities of electronic heat capacity of thulium cuprates in pseudogap state

Precise calorimetric measurements have been carried out in the 7 - 300 K temperature range on two ceramic samples of thulium 123 cuprates TmBa2Cu3O6.92 and TmBa2Cu3O6.70. The temperature dependence of the heat capacity was analyzed in the region where the pseudogap state (PGS) takes place. The lattice contribution was subtracted from the experimental data. The PGS component has been obtained by comparing electronic heat capacities of two investigated samples because the PGS contribution for the 6.92 sample is negligible. The anomalous behavior of the electronic heat capacity near the temperature boundary of PGS was found. It is supposed that this anomaly is due to peculiarities in N(E) function where N is the density of electronic states and E is the energy of carriers of charge.Comment: 12 pages, 3 Postscript figure

Normal-state resistivity anisotropy in underdoped RBa_2Cu_3O_{6+x} crystals

We have revealed new features in the out-of-plane resistivity rho_c of heavily underdoped RBa_2Cu_3O_{6+x} (R=Tm,Lu) single crystals, which give evidence for two distinct mechanisms contributing the c-axis transport. We have observed a crossover towards "metal-like" (d rho_c/d T > 0) behavior at the temperature T_m which quickly increases with decreasing doping. The "metal-like" conductivity contribution dominates at T < T_m and provides a saturation of the resistivity anisotropy, rho_c / rho_{ab}. The antiferromagnetic ordering is found to block this "metal-like" part of the c-axis conductivity and complete decoupling of CuO_2 planes, which may be the reason of superconductivity disappearance.Comment: RevTex, 4 pages including 4 eps figures. To be published in Phys.Rev.Let

Нерешенные вопросы диагностики рестриктивного типа вентиляционных нарушений

The aim of this study was to determine diagnostic value of an algorithm for restrictive ventilation disorders recommended by the American Thoracic and European Respiratory Society. Methods. We analyzed pulmonary function tests of 148 patients with interstitial lung disease with increased lung elasticity and without airways obstruction. A specific type of restrictive disorders referred to as «non-classic», because it does not match existing diagnostic criteria, was observed in most patients (n = 86). The recommended diagnostic algorithm had low sensitivity (0.42) mainly due to a low informative value of spirometry (VC was within a normal range in 80% of patients with non-classic restrictive pattern).С целью определения эффективности алгоритма диагностики рестриктивного типа вентиляционных нарушений, рекомендованного Американским торакальным и Европейским респираторным обществами, проанализированы результаты легочных функциональных тестов у больных (n = 148) интерстициальными заболеваниями легких с отсутствием признаков обструкции дыхательных путей и повышенной эластичностью легких. В большинстве случаев (n = 86) наблюдался вариант рестриктивных нарушений, названный неклассическим, поскольку он не удовлетворял существующим диагностическим критериям. При использовании рекомендованного к применению алгоритма диагностики рестриктивного типа вентиляционных нарушений продемонстрирована низкая чувствительность (0,42). Основной причиной тому была недостаточная информативность спирометрии – у 80 % больных с неклассическим рестриктивным паттерном жизненной емкости легких показатели оставались в пределах нормальных значений

Problem of spreading fake information in the Internet space analysis

Modern Internet space is filled with various kinds of information, including unreliable, fake information. In the current socio-cultural, socio-political, and socio-economic conditions, we should expect further increase in the spread of fakes and, as a consequence, their negative impact on people’s lives. The article analyses results of a sociological study on the attitude of the Kursk region population to fakes spread in the Internet space. The empirical basis of the study is the results of the online questionnaire survey conducted in September 2022 in the Kursk region. The sample population of the study was 521 people living in the territory of Kursk and Kursk region. Fakes are becoming a real part of life in modern society. Residents of the region are constantly faced with inaccurate information. They recognize its danger and note that fakes nevertheless “attract” their attention. The current situation requires additional measures development to regulate dissemination of information in the Internet space

Low-Dose Ionizing Radiation Affects Mesenchymal Stem Cells via Extracellular Oxidized Cell-Free DNA: A Possible Mediator of Bystander Effect and Adaptive Response

We have hypothesized that the adaptive response to low doses of ionizing radiation (IR) is mediated by oxidized cell-free DNA (cfDNA) fragments. Here, we summarize our experimental evidence for this model. Studies involving measurements of ROS, expression of the NOX (superoxide radical production), induction of apoptosis and DNA double-strand breaks, antiapoptotic gene expression and cell cycle inhibition confirm this hypothesis. We have demonstrated that treatment of mesenchymal stem cells (MSCs) with low doses of IR (10 cGy) leads to cell death of part of cell population and release of oxidized cfDNA. cfDNA has the ability to penetrate into the cytoplasm of other cells. Oxidized cfDNA, like low doses of IR, induces oxidative stress, ROS production, ROS-induced oxidative modifications of nuclear DNA, DNA breaks, arrest of the cell cycle, activation of DNA reparation and antioxidant response, and inhibition of apoptosis. The MSCs pretreated with low dose of irradiation or oxidized cfDNA were equally effective in induction of adaptive response to challenge further dose of radiation. Our studies suggest that oxidized cfDNA is a signaling molecule in the stress signaling that mediates radiation-induced bystander effects and that it is an important component of the development of radioadaptive responses to low doses of IR

Маркеры повреждения головного мозга при тяжелой сочетанной травме

The paper describes a clinical case of early enteral feeding with an immune formula in a patient with significant heart failure after cardiosurgical intervention who is on venoarterial extracorporeal membrane oxygenation. The safety and efficiency of nutritional support were monitored, by estimating blood acid-base balance and oxygenation level and by controlling the residual gastric volume, which enabled the volume of the given enteral mixture to be increased up to 2600 kcal by day 3, by providing the body&#8217;s energy needs determined by calculation techniques. On postoperative day 4 when hemodynamic parameters were satisfactory, extracorporeal membrane oxygenation was disconnected; following 7 days the patient was weaned from artificial ventilation. The length of intensive care unit stay was 14 days. The patient was discharged from hospital in a satisfactory condition. Thus, early enteral feeding may be a safe and effective method of nutritional support in patients on extracorporeal circulation. Key words: extracorporeal membrane oxygenation, early enteral feeding, immune nutrition, cardiosurgery.Представлен обзор литературы о механизмах формирования энцефалопатии при тяжелой сочетанной травме без превалирования тяжелой ЧМТ: гемодинамические нарушения, повреждение эндотелия, апоптоз и антиапоптоз. Предложенные маркеры тяжести повреждения головного мозга могут быть использованы в качестве компонентов комплексной диагностики посттравматической энцефалопатии. Ключевые слова: сочетанная травма, энцефалопатия, диагностика, маркеры повреждения головного мозга

Schwann Cell Precursors Generate the Majority of Chromaffin Cells in Zuckerkandl Organ and Some Sympathetic Neurons in Paraganglia

In humans, neurosecretory chromaffin cells control a number of important bodily functions, including those related to stress response. Chromaffin cells appear as a distinct cell type at the beginning of midgestation and are the main cellular source of adrenalin and noradrenalin released into the blood stream. In mammals, two different chromaffin organs emerge at a close distance to each other, the adrenal gland and Zuckerkandl organ (ZO). These two structures are found in close proximity to the kidneys and dorsal aorta, in a region where paraganglioma, pheochromocytoma and neuroblastoma originate in the majority of clinical cases. Recent studies showed that the chromaffin cells comprising the adrenal medulla are largely derived from nerve-associated multipotent Schwann cell precursors (SCPs) arriving at the adrenal anlage with the preganglionic nerve fibers, whereas the migratory neural crest cells provide only minor contribution. However, the embryonic origin of the ZO, which differs from the adrenal medulla in a number of aspects, has not been studied in detail. The ZO is composed of chromaffin cells in direct contact with the dorsal aorta and the intraperitoneal cavity and disappears through an autophagy-mediated mechanism after birth. In contrast, the adrenal medulla remains throughout the entire life and furthermore, is covered by the adrenal cortex. Using a combination of lineage tracing strategies with nerve- and cell type-specific ablations, we reveal that the ZO is largely SCP-derived and forms in synchrony with progressively increasing innervation. Moreover, the ZO develops hand-in-hand with the adjacent sympathetic ganglia that coalesce around the dorsal aorta. Finally, we were able to provide evidence for a SCP-contribution to a small but significant proportion of sympathetic neurons of the posterior paraganglia. Thus, this cellular source complements the neural crest, which acts as a main source of sympathetic neurons. Our discovery of a nerve-dependent origin of chromaffin cells and some sympathoblasts may help to understand the origin of pheochromocytoma, paraganglioma and neuroblastoma, all of which are currently thought to be derived from the neural crest or committed sympathoadrenal precursors

Assessing the impact off chemicals on the job in the production off synthetic rubber

The aim was to evaluate the impact of complex chemical compounds, including carcinogens released during the manufacture of synthetic rubber on the health of workers.Целью исследований явилась оценка воздействия комплекса химических со-единений, в том числе канцерогенных, выделяющихся при производстве синтетического каучука, на здоровье работающих