ВЕРОЯТНОСТНО-СТАТИСТИЧЕСКАЯ ОЦЕНКА ШЕРОХОВАТОСТИ ПОВЕРХНОСТИ ЭЛЕКТРОИМПУЛЬСНО ПОЛИРОВАННЫХ ДЕТАЛЕЙ

The paper presents methodology and results of investigations pertaining to profilograms of specimen surfaces being polished using electric pulse method and being made of steel 10 и 20Х13 with the help of correlative transformation. It has been established that in the process of polishing topography formation is initiated due to simultaneous surfacing of micro- and sub-micro-irregularities with equal probability and equal intensity. The obtained mechanism for topography formation is justified by the fact that break-down of gas-vapor shell takes place with equal probability as on the micro-profile top so in its cavities on the polished surface in the zones of accidental  non-homogeneity of electric field.Приведены методика и результаты исследования профилограмм электроимпульсно полированных поверхностей образцов из сталей 10 и 20Х13 с помощью корреляционного преобразования. Установлено, что в процессе полирования формирование топографии поверхности происходит за счет одновременного с равной вероятностью и равной интенсивностью сглаживания микро- и субмикронеровностей поверхности. Выявленный механизм формирования топографии обусловлен тем, что пробой парогазовой оболочки происходит с равной вероятностью как на вершинах, так и во впадинах микропрофиля обрабатываемой поверхности в областях случайных неоднородностей электрического поля.

МЕХАНИЗМ АНОДНОГО РАСТВОРЕНИЯ КОРРОЗИОННОСТОЙКИХ И КОНСТРУКЦИОННЫХ УГЛЕРОДИСТЫХ СТАЛЕЙ В УСЛОВИЯХ ЭЛЕКТРОИМПУЛЬСНОГО ПОЛИРОВАНИЯ

In this article were suggested the schemes of anode processes, taking into account the nature of metals, anion structure, pH solution of electrolyte and anode potential by electropulse polishing of corrosion- resisting and structural carbon steels.It is shown and experimentally confirmed, that under conditions of electropulse polishing of anode dissolving of metals, which are contained into corrosion-resisting and structural carbon steels, carried out according to mechanism of complex formation through a set of series and series-parallel of intermediate stages. In the 1st stage on the surface of metals adsorption complexes with participation of chemisorption molecules of water are formed. In the next stages anions of electrolyte’s solution and molecules of water take part. In final stage of dissolving on the surface of anode soluble compounds are formed, which by transition into solution into simple ions are dissociated. It is determined that by electrical-impulse polishing in dissolving of components of corrosion-resisting carbon steels the important role play chemical processes, and anode dissolving of metals take place in the field of mixed electrochemical and diffusion kinetics . Diffusion limitations appear as a result of difficult ion mass transfer through surface salt, oxide and hydro-oxide and absorption-phase coatings.Предложены схемы анодных процессов, учитывающие природу металлов, анионный состав, pH раствора электролита и анодный потенциал при электроимпульсном полировании коррозионностойких и конструкционных углеродистых сталей.Показано и экспериментально подтверждено, что в условиях электроимпульсного полирования анодное растворение металлов, входящих в состав коррозионностойких и конструкционных углеродистых сталей, происходит по механизму комплексообразования через ряд последовательных или последовательно-параллельных промежуточных стадий. На первой стадии на поверхности металлов образуются адсорбционные комплексы с участием хемосорбированных молекул воды. В последующих стадиях принимают участие анионы раствора электролита и (или) молекулы воды. На заключительной стадии растворения на поверхности анода образуются растворимые в воде соединения, которые при переходе в раствор диссоциируют на простые ионы.Установлено, что при электроимпульсном полировании в растворении компонентов коррозионностойких и конструкционных углеродистых сталей значительную роль играют химические процессы, а анодное растворение металлов происходит в области смешанной электрохимической и диффузионной кинетики. Диффузионные ограничения возникают в результате затрудненного ионного массопереноса через поверхностные солевые, оксидные и гидроксидные адсорбционно-фазовые пленки

ИССЛЕДОВАНИЕ МОРФОЛОГИИ И ХИМИЧЕСКОГО СОСТАВА ЭЛЕКТРОИМПУЛЬСНО ПОЛИРОВАННОЙ ПОВЕРХНОСТИ УГЛЕРОДИСТЫХ И КОРРОЗИОННОСТОЙКИХ СТАЛЕЙ

The paper presents results of the investigations pertaining to morphology and chemical composition of thin surface layer of structural carbon and corrosion-resistant steel after the process of electro-impulse polishing. It has been established that removal of metal being polished occurs due to anode processes on the treated surface that leads to formation of surface films that can have different nature and thicknesses.  The paper reveals that under conditions of electro-impulse polishing anodic dissolution of steel takes place with direct participation of anions of electrolyte solution.Приведены результаты исследования морфологии и химического состава тонкого поверхностного слоя конструкционных углеродистых и коррозионностойких сталей после электроимпульсного полирования. Установлено, что съем металла при полировании происходит в результате протекания на обрабатываемой поверхности анодных процессов, приводящих к формированию поверхностных пленок, которые могут иметь различную природу и толщину. В условиях электроимпульсного полирования анодное растворение сталей происходит с непосредственным участием анионов раствора электролита

Headache in juvenile myoclonic epilepsy

The objective of this study was to assess the prevalence of and risk factors for primary headaches in juvenile myoclonic epilepsy (JME). Headache was classified in 75 patients with JME using a questionnaire, and its prevalence was correlated with the literature on the general population and clinical data. Headache was present in 47 patients. Thirty-one had migraine [20 migraine without aura (MO), 11 migraine with aura (MA)]. Fourteen patients with migraine had tension-type headache (TTH) in addition. Sixteen had only TTH. Comparison with the general population revealed a significantly higher prevalence of migraine (RR 4.4), MO (3.6), MA (7.3) and TTH (3.4) in JME. Risk factors for migraine and MO were female gender and for MA family history of migraine in first-degree relatives. Migraine and MA were associated with fairly controlled generalized tonic clonic seizures, MO with absences. Together with its strong genetic background, JME appears to be an attractive homogenous subtype of epilepsy for genetic research on migraine

Network analysis of human glaucomatous optic nerve head astrocytes

<p>Abstract</p> <p>Background</p> <p>Astrocyte activation is a characteristic response to injury in the central nervous system, and can be either neurotoxic or neuroprotective, while the regulation of both roles remains elusive.</p> <p>Methods</p> <p>To decipher the regulatory elements controlling astrocyte-mediated neurotoxicity in glaucoma, we conducted a systems-level functional analysis of gene expression, proteomic and genetic data associated with reactive optic nerve head astrocytes (ONHAs).</p> <p>Results</p> <p>Our reconstruction of the molecular interactions affected by glaucoma revealed multi-domain biological networks controlling activation of ONHAs at the level of intercellular stimuli, intracellular signaling and core effectors. The analysis revealed that synergistic action of the transcription factors AP-1, vitamin D receptor and Nuclear Factor-kappaB in cross-activation of multiple pathways, including inflammatory cytokines, complement, clusterin, ephrins, and multiple metabolic pathways. We found that the products of over two thirds of genes linked to glaucoma by genetic analysis can be functionally interconnected into one epistatic network via experimentally-validated interactions. Finally, we built and analyzed an integrative disease pathology network from a combined set of genes revealed in genetic studies, genes differentially expressed in glaucoma and closely connected genes/proteins in the interactome.</p> <p>Conclusion</p> <p>Our results suggest several key biological network modules that are involved in regulating neurotoxicity of reactive astrocytes in glaucoma, and comprise potential targets for cell-based therapy.</p

INVESTIGATIONS OF MORPHOLOGY AND CHEMICAL COMPOSITION OF ELECTRO-IMPULSE POLISHED SURFACE OF CARBON AND CORROSION-RESISTANT STEEL

The paper presents results of the investigations pertaining to morphology and chemical composition of thin surface layer of structural carbon and corrosion-resistant steel after the process of electro-impulse polishing. It has been established that removal of metal being polished occurs due to anode processes on the treated surface that leads to formation of surface films that can have different nature and thicknesses.  The paper reveals that under conditions of electro-impulse polishing anodic dissolution of steel takes place with direct participation of anions of electrolyte solution

MECHANIZM OF ANODE DISSOLVING OF CORROSION-RESISTING AND STRUCTURAL CARBON STEELS UNDER ELECTROPULSE POLISHING

In this article were suggested the schemes of anode processes, taking into account the nature of metals, anion structure, pH solution of electrolyte and anode potential by electropulse polishing of corrosion- resisting and structural carbon steels.It is shown and experimentally confirmed, that under conditions of electropulse polishing of anode dissolving of metals, which are contained into corrosion-resisting and structural carbon steels, carried out according to mechanism of complex formation through a set of series and series-parallel of intermediate stages. In the 1st stage on the surface of metals adsorption complexes with participation of chemisorption molecules of water are formed. In the next stages anions of electrolyte’s solution and molecules of water take part. In final stage of dissolving on the surface of anode soluble compounds are formed, which by transition into solution into simple ions are dissociated. It is determined that by electrical-impulse polishing in dissolving of components of corrosion-resisting carbon steels the important role play chemical processes, and anode dissolving of metals take place in the field of mixed electrochemical and diffusion kinetics . Diffusion limitations appear as a result of difficult ion mass transfer through surface salt, oxide and hydro-oxide and absorption-phase coatings

Determination of aryl-porphyrins binding constants to biological structures by indirect spectral approach

Молекулярная биофизик

Interferon titer and the 2',5'-oligoadenylate-synthetase activity in rat thymus lymphocytes in conditions of Omeprazol-caused hypergastrinemia

The aim of this work was the determination of rat thymocytes response to hypergastrinemia evoked by hypoacidity and multiprobiotic «Symbiter® acidophilic concentrated» (symbiter) treatment via the estimation of the interferon (IFN) titer and 2', 5'-oligoadenylate (OA)-synthetase activity in lymphocytes. 2', 5'-OA-synthetase is the IFN-induced enzyme. Methods. The micromethod of IFN titer determination by antiviral activity, spectrophotometrical method of 2', 5'-OA-synthetase activity determination. Results. It was shown that the IFN production by cultivated thymocytes is amplified while the 2', 5'-OA-synthetase activity decreases in these cells in conditions of hypoacidity caused by the 28-days omeprazol treatment. The treatment of animals by symbiter against a background of hypoacidity causes the augmentation of IFN production by thymocytes, but does not stimulate the 2', 5'-OA-synthetase activity. The IFN production by thymocytes in response to IFN inducers (PHA and cycloferone) in vitro is intensified comparatively to the control at hypoacidity and symbiter treatment. Conclusions. The multiprobiotic symbiter exhibits interferonogenic properties. The IFN synthesis in response to induction in vitro is intensified in comparison with healthy animals at both hypoacidity and symbiter treatment while the 2', 5'-OA-synthetase acivity in thymocytes decreases

PRODUCTIVITY OF WINTER WHEAT AND METHODS OF TILLAGE

The article considers opportunities and results of winter wheat cultivation using different methods of tillage under insufficient and unstable humidity of the south of Russia. The experiments were carried out as steady trials with the use of different machinery able to cultivate the soil for winter wheat at various depth, including non-tillage variants.  We have obtained the results of biometric characteristics of winter wheat and its productivity in the conditions of 2012-2013 years. The analysis of received data shows that biometric characteristics of winter wheat vary depending on variants of tillage. Winter wheat grown on the cultivated soil showed poor biometric characteristics and reduced its productivity on 20-30% in comparison with a non-tillage variant.   A correlation analysis has been carried out to determine effect of tillage on winter wheat biometric characteristics and on productivity. Such characteristics as mass of straw with spike, number of productive spikes, mass of grain, number of seeds per spike possess a significant statistic correlation (the co-efficient is more than±0,815). Winter wheat gave its largest yields in non-tillage variants. It exceeded its productivity in non-tillage variants on 13-29% which tells about potential of the studied technology of winter wheat production and the correlation analysis proves it. The correlation between winter wheat biometric characteristics and productivity in a non-tillage variant is determined by a co-efficient of correlation of 0,739-1,0. The total influence of considered winter wheat biometric characteristics on its productivity was assessed by a co-efficient of multiple correlation (R) and a co-efficient of determination R2, which were 0,886-0,999 and 0,784-0,999 for low power methods of tillage