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Herein, experimental observation of the pressure‐induced softening of the zone‐edge transverse acoustical (TA(X)ze) phonon in the zincblende indium antimonide is for the first time reported. Experimental data allow for determination of Grüneisen parameter for the TA(X)ze phonon mode. The density‐functional theory calculations performed within quasiharmonic approximation at 0 K also reveal the softening of the TA(X)ze at high pressure, although the experimental value of its frequency shift is almost three times smaller than the theoretical one. In contrast, pressure dependences of optical phonons are well reproduced in our calculations. Similar calculations for GaSb and InP result in good agreement with available experimental data for optical and, as opposed to InSb, also for TA(X)ze phonons. The fact that the quasiharmonic theory works well for GaSb and InP may suggest that anharmonicity of acoustical phonons in these compounds is insignificant at room temperature. The possibility of enhanced anharmonicity of TA(X)ze phonon in InSb is discussed. The pressure of transition derived from experimentally determined shift of TA(X)ze frequency for InSb does not fit the recently proposed model of Weinstein working well for over 20 semiconductors, which also shows the specificity of InSb especially in comparison to other cubic III–V semiconductors. [ABSTRACT FROM AUTHOR]

Introduction Internet addiction disorder (IAD) is characterized by an individual’s inability to control his/her Internet use, which may result in marked distress and functional impairment. Systematic reviews show that excessive screen-time is negatively associated with well-being and positively associated with reduced quality of life in young people. There is growing evidence that IAD is related to comorbidities such as depression but relatively little is known about fatigue in adolescents with IAD. Objectives Accumulating evidence suggests that fatigue is a central component of IAD. Depression is also related to IAD. However, there is a lack of evidence regarding whether there is a strong correlation between the severity of IAD and the rate of depression. Our objectives were to describe depression and fatigue in adolescents diagnosed with IAD. Methods Study included 94 participants with IAD and 88 controls, all aged 12–17 years. Depression was assessed by the Beck Depression Inventory Scale (Georgian version), and fatigue by the Pediatric Quality of Life Initiative (Georgian version) multidimensional fatigue scale. Results Adolescents with severe IAD are 5.63 times more likely to show symptoms of moderate or severe depression than children with mild or moderate Internet addiction. Those with severe IAD showed 6.62 times more cognitive fatigue, 7.81 times higher sleep/rest fatigue and 11.11 times higher general fatigue than children with mild and moderate Internet addiction. Conclusions IAD can lead to depression and fatigue, which can affect adolescent’s psychological and social well-being. Mechanisms for prevention and ongoing support are needed for adolescents and their families. Disclosure No significant relationships.

Paediatric epilepsy is a multifaceted neurological disorder with various aetiologies. Up to 30% of patients are considered drug-resistant. The background impact of interfering inflammatory and neuronal pathways has been closely linked to paediatric epilepsy. The characteristics of the inflamed state have been described not only in epilepsies, which are considered prototypes of an inflammatory pathophysiology, but also in patients with drug-resistant epilepsy, especially in epileptic encephalopathies. The imbalance of different cytokine levels was confirmed in several epileptic models. Chemokines are new targets for exploring neuroimmune communication in epileptogenesis, which control leukocyte migration and have a possible role in neuromodulation. Additionally, prostaglandin E2 (PGE2) is an important effector molecule for central neural inflammatory responses and may influence drug responsiveness. We measured the serum interictal quantitative levels of chemokines (CCL2, CCL4, CCL11) and PGE2 in correlation with the seizure frequency and severity in controlled and intractable childhood epilepsies. Our refractory seizure group demonstrated significantly increased concentrations of eotaxin (CCL11) compared to the controlled epilepsy group. The higher level of CCL11 was correlated with an increased seizure frequency, while the PGE2 levels were associated with the severity of seizure and epilepsy, supporting the findings that proinflammatory cytokines may contribute to epileptogenesis and possibly have a role in developing seizure resistance.

Purpose. The quality of passenger’s and good’s transportation by a magnetically levitated train (MLT) is a key criterion for evaluating its consumer properties. The dynamics of a train’s electromechanical subsystem (EMS) has a decisive influence on this quality. Non-stationary modes of this subsystem’s motion, such as a speed increase, service and emergency braking, as well as the passage of the tunnel are especially critical. Therefore, the train’s motion in such modes is limited by acceptable safety standards. Based on this, the purpose of this study is to assess the dynamic qualities and load of the train in the above-mentioned non-stationary modes. Methodology. At the present stage, the main and most universal tool for analyzing and synthesizing processes in systems is their mathematical and, in particular, computer modelling. On this basis, the work was done by conducting a series of experiments with computer model of EMS MLT dynamics. This computer model was obtained as a result of the relevant transformation of the corresponding mathematical model into it. The mentioned computer model was programmatically recorded in the input language of the Mathematica computer mathematics system. Findings. The obtained results of modelling are presented in graphical form and reflect the train's motion in the modes of acceleration, the passage through a tunnel, as well as service and emergency braking. The control by the train's electromechanical subsystem in all considered transient modes of motion, with the exception of emergency braking, is carried out by changing the voltage feeding of the linear synchronous motor’s armature’s winding according to one or another law. Therefore, during modelling the train’s motion in each of these modes, frequency, amplitude-frequency, and phase-frequency control options for the motor’s armature’s voltage changing were considered. Analysis of the simulation results made it possible to estimate the MLT’s dynamic qualities in various non-stationary modes of motion and its load in their process. Originality. The research suggests setting the priority of the holistic consideration of non-stationary modes of MLT's EMS's motion. Practical value. The main manifestation of the practical value of the work is the possibility, in the case of using its results, of significant increasing in the efficiency of dynamic studies of MLT while reducing their resource intensity.

Introduction Internet addiction disorder (IAD) is defined as one of the commonest disorder in children and adolescents affecting 40 percent of them. Although it does not cause mental disorders it is known that IAD is commonly related with attention deficit and hyperactivity disorder (ADHD). The best approach to asses attention is recording of event related potentials (ERPs) especially late response like P300. There are growing evidence regarding assessment of attention in IAD with different questionnaires but less is known about evidence received with more valid measurements like P300. Objectives The aim of our study was to measure attention parameters in IAD subjects by using the most valid test–latency and amplitude of P300. We have examined 70 children with IAD aged 5-18 years. Children were divided into two groups: Group 1 (40 children) was matched as a study group including children with IAD and group 2 controls (30 children) without IAD and without ADHD. Methods IAD was assessed by Young IAD scale. Children with Young scale less than 20 and with IQ less than 85 were excluded from the study. Recording of P300 was done by international protocol using oddball paradigm method. Statistical analysis was done by SSPS 26. Results In study group increase in P300 latency was found (mean range 350-375 msc) while amplitude was normal (p

Purpose. The implementation of the magnetically levitated train’s (MLT) levitation force (LF) occurs during the interaction between fields of superconducting train’s (STC) and short-circuited track’s contours (STC), which are included in to levitation module (LU). Based on this, the purpose of this study is to obtain a correct description of such interaction. Methodology. At the present stage, the main and most universal tool for the analysis and synthesis of processes and systems is their mathematical and, in particular, computer modeling. At the same time, the radical advantages of this tool make even more important the precision of choosing a specific methodology for research conducting. This is particularly relevant in relation to such large and complex systems as MLT. For this reason, the work pays special attention to the reasoned choice of the selective features of the research paradigm. Findings. The analysis results of existing versions of LF implementation’s models show that each of them, along with the advantages, also has significant drawbacks. In this regard, one of the main results of the study should be the construction of this force implementation’s mathematical model, which preserves the advantages of the mentioned versions, but free from their shortcomings. The rationality of application, for the train’s LF researching, of an integrative holistic paradigm, which assimilates the advantages of the electric circuit's and magnetic field's theory’s, is reasonably justified in work. Originality. The scientific novelty of the research – in priority of such a paradigm’s and the corresponding version’s of the LF’s implementation’s model’s creating. Practical value. The main manifestation of the practical significance of the work is the possibility, in the case of using its results, to significantly increase the effectiveness of dynamic MLT research while reducing their resource costing.

Purpose. Traction force implementation (TFI) by the motor of magnetic levitation train (MLT) occurs in the process of electric-to-kinetic energy transformation at interaction of inductor and armature magnetic fields. Ac-cordingly, the aim of this study is to obtain a correct description of such energy transformation. Methodology. At the present stage, a mathematical and, in particular, computer simulation is the main and most universal tool for analysis and synthesis of processes and systems. At the same time, radical advantages of this tool make the precision of selection of a particular research methodology even more important. It is especially important for such a large and complex system as MLT. Therefore the special attention in the work is given to the rationale for choosing the research paradigm selective features. Findings. The analysis results of existing TFI process model versions indicate that each of them has both advantages and disadvantages. Therefore, one of the main results of this study was the creation of a mathematical model for such process that would preserve the advantages of previous versions, but would be free from their disadvantages. The work provides rationale for application (for the purposes of research of train motor TFI) of the integrative holistic paradigm, which assimilates the advantages of the theory of electric circuit and magnetic field. Originality. The priority of creation of such paradigm and corresponding version of FI model constitute the originality of the research. Practical value. The main manifestation of practical value of this research in the opportunity, in case of use of its results, for significant increase in efficiency of MLT dynamic studies, on the condition that their generalized costs will not rise.

Purpose. The basic criterion of the magnetically suspended train's consumer estimation is a quality of its mechanical motion. This motion is realized in unpredictable conditions and, for purposefulness preservation, should adapt to them. Such adaptation is possible only within the limits of system’s dynamic sufficiency. Sufficiency is understood as presence at system of resources, which allow one to realize its demanded motions without violating actual restrictions. Therefore presence of such resources is a necessary condition of preservation of required purposefulness of train's dynamics, and verification of the mentioned sufficiency is the major component of this dynamic research. Methodology. Methods of the set theory are used in work. Desirable and actual approachability spaces of the train are found. The train is considered dynamically sufficient in zones of the specified spaces overlapping. Findings. Within the limits of the accepted treatment of train's dynamic sufficiency, verification of its presence, as well as a stock (or deficiency) of preservations can be executed by the search and the subsequent estimation of such overlapping zones. Operatively (directly during motion) it can be realized on the train's ODC with use, for example, of computer mathematics system Mathematica. It possesses extensive opportunities of highly efficient and, at the same time, demanding an expense concerning small resources information manipulation. The efficiency of using of created technique is illustrated on an example of vehicle's acceleration research. Calculation is executed with use of the constructed computer model of interaction of an independent traction electromagnetic subsystem of an artifact with its mechanical subsystem. Originality. The technique of verification of the high-speed magnetically suspended train's dynamic sufficiency is developed. The technique is highly efficient, it provides sufficient presentation and demands an expense of the moderate resources at use (especially in cases of not too high dimensions of spaces of conditions and decision-making of system). Practical value. The technique can be used with success during dynamic research, including the magnetically suspended trains.

The arrangements of electro-dynamic transport systems with the flat track structure are described and the fluctuations and stability of levitation motion of their vehicles are evaluated. It is shown that under rational choice of main parameters of the systems a stable levitation motion of the vehicles in straight-line and curvilinear sections of the track is provided.

The method of constructing the goal-directed dynamics of magnet-levitation train is offered. The components of its motion are divided on useful and parasitic. Their situation is expected unpredictable.

The technique of hierarchic construction of magnetic levitated train motion is offered. Its advantages and expediency of three-leveled system regulator were grounded. The global algorithm of its work is constructed.