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Abstract

The aim of study is to analyze the tDCS influence on stress-induced disorders in rats with low stress sustainability and endurance. The animals with a low stress sustainability and endurance were divided into 3 groups: the comparison 1, the comparison 2 and the main. The control group consisted of intact rats. The rats of the comparison group 1 were subjected to orthostatic stress 24 hours after the 1st forced swimming test. The rats of the comparison group 2 and the main one were conducted the 2nd forced swimming test on the 7th day of the experiment, and 24 hours later they were subjected to the orthostatic stress. Rats of the main group got tDCS sessions after the 1st forced swimming test. The development of the orthostatic stress is accompanied by an increase in plasma content the following components: adrenaline by 88.9%, ACTH in 10.5 times, corticosterone by 70.1%, IL-1β by 178.2%, IL-6 in 6.7 times, IL-10 by 37.1% in comparison with intact animals. The usage of tDCS in rats with low stress sustainability and endurance increased the swimming duration by 47.7%. During the OS it was also accompanied by a decrease in plasma content: adrenaline in 1.4 times, ACTH in 8.2 times, corticosterone in 1.4 times, IL-1β in 1.5 times, IL-6 in 2.2 times, IL-10 in 1.2 times, relative to the comparison group 2. The obtained data showed the essential effect of tDCS on stress-related changes in the content of cytokines and hormones of blood.

Introduction Transcranial electrical stimulation using weak current may be a promising tool to modulate cerebral activity in a noninvasive, and to some extent reversible, selective way [ 1 ]. Transcranial direct current stimulation (tDCS) is a useful noninvasive technique that imposes a weak direct electrical current (1-2 mA) to modulate the activity of neurons in the brain. The experiments suggested that electrodes placed on the head can produce noticeable neurological changes depending on the current direction [ 2 ]. The current results in an electric field

. Treatment of depression with transcranial direct current stimulation (tDCS): a review. Exp. Neurol. 2009; 219 (1): 14–19.73 83. Zyss T. Przezczaszkowa stymulacja stałoprądowa tDCS i inne pokrewne techniki w terapii zaburzeń psychicznych. Psychiatr. Pol. 2010: 44 (4) s.505-518 84. Caetano SC, Fonseca M, Olvera RL, Nicoletti M, Hatch JP, Stanley JA et al. Proton spectroscopy study of the left dorsolateral prefrontal cortex in pediatric depressed patients. Neurosc. Lett. 2005; 384 (3): 321–326 85. Andrade C. Transcranial direct current stimulation for refractory auditory

-auswertung in der Stoffwirtschaft. VEB, Leipzig, 1974 (edition in Russian, 1977) Polanowski S.: Errors arising from relating the piston TDC to zero points of derivatives of ship engine cylinder pressure function (in Polish, abstract in English). Proceedings of KONES Conference 2000, (saved in Warsaw Institute of Aeronautics) Polanowski S.: Main sources of measurement errors of mean indicated pressure of ship engines in service conditions (in Polish, abstract in English). Journal of KONES, 1995, (saved in Warsaw Institute of Aeronautics) Polanowski S., Errors in Toking

, with moderate humidity (⁓50%). Before the matches, a 20-min standardized warm-up was performed, which incorporated continuous running and displacement, followed by joint mobility. Then, explosive exercises were performed, such as strides, changes of direction and skipping. A short break was provided to hydrate and then specific technical tasks were carried out. Match-play analysis Running-demands data registered included total distance covered (TD), distance covered at velocities faster than 18 km·h -1 (TDC >18km·h -1 ), total accelerations (Accel) and decelerations

Abstract

A cylinder liner and piston ring running under starved lubrication near the top dead centre (TDC) and bottom dead centre (BDC) cause abnormal friction and wear during operation of a marine diesel engine. The method of laser texturing is proposed to improve the surface friction property under this condition. Spherical crown pits with different parameters were formed on the surface of samples by femtosecond laser processing. The BDC and TDC conditions of oil starvation were simulated in a reciprocating friction and wear experiment, and a numerical model of surface texture lubrication based on the Reynolds equation was established. The influence of the distribution density, diameter, and depth parameters of the texture on the surface properties was studied. In the BDC condition, compared with the untextured surface, the average coefficient of friction (COF) can be reduced by up to 24% and the average friction force can be reduced by up to 18%. In the TDC condition, the COF can be reduced by up to 19%, and the average friction force can be reduced by up to 18%. Therefore, the textures with various parameters should be arranged in different positions on the cylinder liner; more attention should be paid to the optimisation of diameter in the texture of the cylinder liner near the BDC, whereas more attention should be paid to the optimisation of distribution density in the texture of the cylinder liner near the TDC

Abstract

The aim of analysis presented in the article is results of measurements of torsional deflections of a crankshaft of three-cylinder internal combustion diesel engine. The wavelets of the run of torsional twists were processed by decomposition to harmonics using FFT. In order to exactly recognize all dynamic aspects of gas forces acting during working stroke, decomposition was done in two ways: first one relaying on records encompassing one working cycle (two revolutions), the second one based at separated periods encompassing angular an interval from TDC (Top Dead Centre) of one cylinder to TDC of subsequent in firing order. For three-cylinder engine, width of the interval is 240 degrees of crank angle. In order to obtain reliable results, torsional deflection signals acquisitions were recorded numerous times including changes of outer conditions (temperature, atmospheric pressure) and different values of the engine loads. The main goal of conducted experiments was looking for an answer of a question if exist any differences between frequency spectrums of harmonics of run of full cycle ( two revolutions) and the same cycle divided by three separate intervals. Analysis was conducted in order to state any possibility of diagnostic signals acquisition caused by abnormalities of combustion process. Results were presented in form of comparison of frequency spectra taken from full cycle and divided intervals.

Abstract

A spark-ignited Rapid Compression Machine (RCM) has been used to investigate the influences of the different proportions of methane-propane mixtures on the combustion characteristics at knock threshold operating condition. First, the threshold operating points of the mixtures have been obtained and the results indicated that the piston driving pressure reduces from 142 bars to 90 bars as the propane content in the mixture increases. As a spark plug was fitted in this RCM, the optimum spark timing was also investigated. It was established that spark timing should be set synchronize with the piston at TDC, due to the free movement of the piston. In most RCMs, piston can move toward TDC following the equilibria of forces due to the absence of con-rod. Finally, knock intensity of the different mixtures has been studied. Pre-heating system in RCM with and without trace heating system; effects of flow-rate and lambda variations on peak pressure, ignition delay time and ARR; threshold operating conditions of pure methane, 90% methane and 10% propane, 80% methane and 20% propane, 70% methane and 30% propane; effect of driving pressure on the knocking intensity for mixture of methane and propane for heavy and light knockings are presented in the article.

Abstract

Research of efficient and ecological parameters was carried out with compression ignition (CI) engine using diesel fuel and additionally supplied hydrogen and oxygen (HHO) gas mixture. HHO gas is produced by electrolysis when the water was dissociating. At constant engine’s brake torque and with increasing HHO gas volumetric concentration in taken air up to 0.2%, engine efficient indicators varies marginally, however, with bigger HHO concentration these parameters becomes worse. HHO increases smokiness, but it decreases NOx concentration in exhaust gas. Numerical analysis of combustion process using AVL BOOST software lets to conclude that hydrogen, which is found in HHO gas, ignites faster than diesel fuel and air mixture. Hydrogen combustion before TDC makes a negative work and it changes diesel fuel combustion process – diesel ignition delay phase becomes shorter, kinetic (premixed) combustion phase intensity gets smaller.

Abstract

Several studies have indicated that the prevalence of unhealthy body weight in individuals with autism spectrum disorder (ASD) is high. It is unclear whether factors related to the weight status of children and adolescents with ASD are the same or different from factors associated with the weight status of typically developing children (TDC). The objective of this review was to identify key factors associated with the higher rates of unhealthy weight observed in individuals with ASD and create a structural model, which could be used for future autism intervention research. This review summarizes the current state of knowledge on the genetic basis of obesity in ASD, special treatment (behavioral and medical, including diet and psychotropic medications), psychological (depression and anxiety) as well as somatic comorbid disorders such as feeding problems, sensory processing disorders, gastrointestinal problems and sleep disorders, physical activity and sedentary behaviors, loneliness and social isolation, and family functioning (maternal depression and stress).