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Mastering toilet training skills in childhood is considered an important developmental determinant. Acquiring proper toilet skills in children with developmental disorders is often delayed. The aim of this paper is to present possible problems that occur in children with intellectual disability, autism spectrum disorder, and cerebral palsy during toilet training, as well as to indicate the interventions that have proven to be effective in this domain. The paper points out the specifics of each of the treated clinical pictures regarding mastering toilet training skills. Behavioral interventions were specially addressed, and it was emphasized that they should be individualized based on the physical limitations and cognitive status of a child. Effective interventions include reinforcement, prompting, extinction, demonstrations, visual schedules, and others derived from treatment programs for children with developmental disorders.

The possibility of substitution of road transport of dangerous goods by rail was investigated through the analysis of transport costs. Transport costs in the transport of dangerous goods in road traffic in the work of computers are based on generally accepted methods and available data. Also, the costs were calculated if the transport would take place by rail on those routes and for one number for which it would be expedient. It was used with appropriate statistical methods to determine some dangerous goods by transport routes.

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Post-sintering of magnesium titanate ceramics by hot isostatic pressing (HIP) in an oxygen-free atmosphere significantly alters various electrical properties of the product. In particular, the sintered material becomes a semiconductor. The aims of this paper are: to extend our investigations of the electrical properties of this material by expanding the frequency range of measurements, to design interpolation formulas for the frequency dependence of the complex relative permittivity, and to propose HIP-sintered magnesium titanate as a material for thermistors that have a negative-temperature-coefficient resistance (NTCR), as well as for varistors. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 32005 and Grant no. ON 172057]

We present a design of a high-gain quad array of nonuniform helical antennas. The design is obtained by optimization of a 3-D numerical model of four nonuniform helical antennas placed above a ground plane, including a model of a feeding network, utilizing the method of moments with higher-order basis functions. The gain of one optimal nonuniform helical antenna can be about 2.5 dB higher than the gain of a uniform helical antenna of the same axial length. Creating a 2×2 array further increases the gain up to about 6 dB. The resulting quad array fits into a box whose dimensions are 2.5×3.3×3.3 wavelengths, and the gain in the main radiating direction is about 20.5 dBi in the frequency range from 0.9 GHz to 1.1 GHz. The design is verified by measurements of a prototype of the quad array.

The cavernous hemangiomas are the most common intra orbital tumors found in adults of the middle age. Although histological benign, they can encroach on intra orbital or the adjacent structures (optic nerve) and be considered anatomically or positional malignant. We present a case report of orbital cavernous hemangioma of right orbit in young women after pregnancy, from Topola near Kragujevac (Central Serbia) with visual compromise and it's by trans-nasal endoscopic surgical management. Our patient was controlled and treated with the symptomatic therapy, topical therapy with artificial tears and surgical treatment. Our patient has optimal visual acuity of affected right eye after surgical treatment of orbital tumor. Surgical treatment of symptomatic orbital cavernous hemangioma is safe and effective, so that the cosmetic results are the important parameter to evaluate the clinical outcome.

Introduction. The trans-isomer of resveratrol is the active ingredient of Poligonum cuspidatum, known for its medicinal properties and traditionally used in the treatment of neuropsychiatric disorders. It is also found abundantly in the skin of red grapes and red wine. Previous studies have suggested that trans-resveratrol demonstrates a variety of pharmacological activities including antioxidant, anti-inflammatory, as well as neuroprotective properties and procognitive effects. Objective. The goal of the present study was to examine the influence of trans-resveratrol on behavior in rats and its antidepressant properties. Methods. Male Wistar rats were treated intraperitoneally (i.p.) with the increasing doses of trans-resveratrol (5, 10 and 20 mg/kg) or vehicle (dimethyl sulfoxide - DMSO), 30 minutes before testing of the spontaneous locomotor activity or forced swimming. For the experiments, the behavior of the animals was recorded by a digital camera, and the data were analyzed by one-way ANOVA, followed by Tukey post-hoc test. Results. Testing of spontaneous locomotor activity, after the application of vehicle or increasing doses of trans-resveratrol, showed no statistically significant difference between groups (p>0.05). In the forced swim test, one-way ANOVA indicated statistically significant effects of trans-resveratrol (p0.05). Conclusion. The results from our study suggest that trans-resveratrol produces significant effects in the central nervous system. After single application, it has acute antidepressant effects, but without influence on locomotor activity. [Projekat Ministarstva nauke Republike Srbije, br. TR31020 i br. 175076]

Magnesium (Mg) is an essential element that catalyses more than 300 enzyme systems. Its effects on the central nervous system are exhibited through the blocking of activity of N-methyl D-aspartat (NMDA) receptors and potentiating of GABA-ergic neurotransmission. Due to the vast importance of these two neurotransmission systems in the fine regulation of the central integrative function activity, the aim of this research was to test the anxiolytic and antidepressive effects of magnesium, after acute and repeated application, and its influence on general behavioural parameters. In this research Wistar albino rats were treated with increasing doses of Mg chloride 6-hydrate (MgCl 10, 20, 30 mg/kg). In order to determine anxiolytic and antidepressive properties of magnesium two models were used: elevated plus maze (EPM) and forced swim test (FST). Behavioural parameters (stillness and mobility) were recorded during acute and repeated administration of the active substance. Results of EPM testing showed no significant difference between groups, p>0.05. After acute application of increasing doses of magnesium chloride hydrate in FST, we showed the statistically significant difference in immobility time between the group of animals treated with Mg and the control group treated with the solvent, p

Benzodiazepines are well established as inhibitory modulators of memory processing. This effect is especially prominent when applied before the acquisition phase of a memory task. This minireview concentrates on the putative subtype selectivity of the acquisition-impairing action of benzodiazepines. Namely, recent genetic studies and standard behavioral tests employing subtype-selective ligands pointed to the predominant involvement of two subtypes of benzodiazepine binding sites in memory modulation. Explicit memory learning seems to be affected through the GABAA receptors containing the α1 and α5 subunits, whereas the effects on procedural memory can be mainly mediated by the α1 subunit. The pervading involvement of the α1 subunit in memory modulation is not at all unexpected because this subunit is the major subtype, present in 60% of all GABAA receptors. On the other hand, the role of α5 subunits, mainly expressed in the hippocampus, in modulating distinct forms of memory gives promise of selective pharmacological coping with certain memory deficit states.

The aim of the study was to investigate the morphology of mesothelial cells of the peritoneum of patients with terminal renal failure (TRF), taken by the biopsy immediately before the onset of peritoneal dialysis (PD), and to compare it with the findings in patients with PD. The samples were prepared in the way standard for light microscopy and transmission electron microscopy. In patients with TRF intracytoplasmatic inclusions could be observed, unusual protrusions of mesothelial apical surfaces, deformation of mesothelial cells and their detachment from the basal membrane, as well as the dilatated cisternae of granulated endoplasmatic reticulum with filamentous structures in some of them. In patients on PD cytoplasmic protrusions of different shapes and contents were observed at the surface of mesothelial cells, multiplication of basal membrane, occurrence of young forms of mesothelial cells as well as the detachment of those cells from the basal lamina.

In the Church of Saint Stephen in Duljevo, not far from Budva (Paštrovići) an interesting composition of the founders (ktetores) has been preserved. In accordance with an early Serbian tradition, it was painted on the southern wall in the western bay of the naos (drawing 1), and it is possible that it extended over the southern part of the western wall that was demolished very long ago. The Duljevo composition of the founders now depicts the images of the patron saint of the church, Saint Stephen, the First Martyr, painted on the southern side of the south-west pilaster, and the presentations of the two rulers to the west of him (drawing 2). The patron saint of the church who was the protector of the Serbian medieval state and its rulers, is represented in a deacon's sticharion, with a censer in his hands, blessing the founders. The ruler in his prime approaches the First Martyr, presenting him with a model of the church (drawing 2, figs. 1, 2)...

Altered by repairs and largely concealed by later additions, the walls of the exonarthex in the cathedral Church of St. George near Berane (Vasojevići), now reveal very little of their earlier fresco decoration. There was the developed cycle of a frescoed menology depicted in the higher zones of the walls, whereas in the lowest zone were the images of saints archangels and the portraits of rulers. Judging by analogies that can be established with similar Serbian monuments of that epoch, the vault probably depicted the Ecumenical Councils...

This article is intended to present the latest scientific findings about the interception of frequency hoping signals. The probability of intercepting frequency hopping signals by means of modern search receivers or scanning direction finders is calculated on a general basis and with particular attention to multichannel receivers and overlapping search and frequency hopping ranges. The article also deals in detail with the timing of the receiver sequence coinciding with the hopper sequence. For the sake of simplicity, ideal conditions are assumed.

We present a design of reflector impulse radiating antenna (IRA) with six feeding arms and a printed tapered balun that also provides broadband matching to a $50 ~\Omega $ system. The design is obtained by thorough numerical analysis and optimization. Six feeding arms provide a lower input impedance while maintaining the same boresight gain in comparison to an IRA with four arms. By placing the balun in the antisymmetry plane of the antenna, boresight gain is practically intact and the resulting antenna construction is rigid. In order to increase the power handling for continuous-wave excitations, the resistors between the arms and the reflector are omitted yielding an antenna that can handle at least hundreds of watts. The compromises that arise when omitting the resistors are discussed. The results are verified by comparing the measurements of the fabricated prototype to the results obtained by the numerical analysis. [ABSTRACT FROM AUTHOR]

We present a general approach for antenna design and optimization based on consensus of results from a number of independently trained deep neural networks (DNNs). The aim of using the consensus is to reduce the uncertainty of results from a single DNN. The approach leads to several orders of magnitude faster antenna optimization and design compared to the optimization based on a full-wave solver and allows a compromise between the analysis speed and its accuracy. The used DNNs are multilayer perceptrons (MLP) with multiple fully connected hidden layers. As an example, we consider the Yagi–Uda antenna with four design parameters and optimize it for the maximal forward gain. The training of neural networks is done on datasets of several sizes, up to 1 million antenna samples. The samples are generated either randomly or at a uniform grid over the design space using the method of moments. [ABSTRACT FROM AUTHOR]

Two general approaches to multiminima optimization are considered. The first approach is based on repetition of a single minima method (e.g., the Nelder-Mead simplex applied to the best solution in a set of random trials). The second approach is based on a coarse estimation of local minima using initial set of points and local optimization starting from these local minima (e.g., random search as a generator of the initial set of points and Nelder-Mead simplex as a local optimizer). A comparison of various optimization algorithms has been done on one analytical problem and two well-known examples of antenna design. It is found that: a) the multiminima method based on coarse estimation enables finding more minima with smaller number of iterations than that based on repetition, b) the best multiminima methods are comparable with the best single minima methods in a number of iterations needed for finding the global minima, and c) the multiminima method based on coarse estimation restarted with different weighting coefficients of multiobjective cost function enables efficient Pareto optimization. Index Terms--Automated design, black-box optimization functions, heuristic multiminima antenna optimization, hybrid optimization algorithms, Nelder-Mead simplex, Pareto front.

A novel high-precision model of a custom-made coaxial chamber used for broadband measurement of the relative complex permittivity at microwave frequencies is presented. The model is based on a surface integral-equation formulation of the method of moments tailored for bodies of revolution. All singular integrals encountered in the numerical analysis are calculated in a unified way with a novel integral transformation, which enables the precision of up to 12 significant digits using the 64-bit representation of real numbers. The dielectric parameters are estimated from the reflection-coefficient measurement of the chamber with a disk-shaped dielectric sample by comparison of the measured data with the high-precision numerical analysis of the chamber. The complete measurement procedure is illustrated and verified using samples of known dielectric properties. [ABSTRACT FROM AUTHOR]

An approach to singularity cancelation by a variable transformation of Green’s function in 2-D case, having log($R$) singularity, is outlined. It is intended for the method of moments analysis of 2-D structures of both curvilinear and flat cross sections. If the transformation is used with Legendre or Chebyshev polynomials as entire-domain basis functions, all involved integrals can be calculated with high precision using Gauss–Legendre quadrature. The optimal parameter of the transformation, having the minimal number of integration samples needed to reach 14-digit precision, is provided. Error estimations are presented for calculated current distributions on strips up to 400 wavelengths wide, analyzed with up to 1500 entire-domain basis functions. [ABSTRACT FROM AUTHOR]

We present a design of a high-gain quad array of nonuniform helical antennas. The design is obtained by optimization of a 3-D numerical model of four nonuniform helical antennas placed above a ground plane, including a model of a feeding network, utilizing the method of moments with higher-order basis functions. The gain of one optimal nonuniform helical antenna can be about 2.5 dB higher than the gain of a uniform helical antenna of the same axial length. Creating a 2×2 array further increases the gain up to about 6 dB. The resulting quad array fits into a box whose dimensions are 2.5×3.3×3.3 wavelengths, and the gain in the main radiating direction is about 20.5 dBi in the frequency range from 0.9 GHz to 1.1 GHz. The design is verified by measurements of a prototype of the quad array. [ABSTRACT FROM AUTHOR]