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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.

Colorado State University, Department of Electrical and Computer Engineering, Fort Collins, CO, USA; e-mail: notaros@colostate.edu, anamanic@engr.colostate.edu, elene.chobanyan@colostate.edu University of Belgrade, School of Electrical Engineering, Belgrade, Serbia; e-mail: milanilic@etf.rs, olcan@etf.rs ICT College, Belgrade, Serbia; e-mail: miroslav@ieee.org Abstract  Hybrid higher order numerical methods for electromagnetic modeling are presented based on the method of moments in surface and volume integral equation formulations, finite element method, and diakoptic domain decomposition.

We present an approach for modeling of human bodies in crowds for the analysis of channel parameters in wireless body area networks. The approach uses distributed surface impedances with method of moments based on surface integral-equation formulation. It significantly reduced the computer resources needed for the electromagnetic analysis, and keeps the final results accurate in a statistical sense.

We outline an implementation of out-of-core direct solver for method of moments-based electromagnetic code. It is designed and executed on a computer cluster where each node has one or more graphical processing units. The algorithm employs simultaneously multi-node parallelism of a cluster architecture and multi-processor parallelism of graphical processing units. This accelerates the overall analysis and allows solving larger problems. The complexity of the solvable problems is limited only with computer resources of the cluster. We perform numerical experiments on a cluster with 8 nodes and with 2 graphical processing units per node. The achieved efficiency of multi-node solution is around 80%. As an illustration of the efficiency of the approach, the radiation pattern of a microstirp antenna on a helicopter fuselage, and monostatic radar cross section of a global hawk are provided, as well as the simulation times.

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.

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.

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. Os hemangiomas cavernosos são os tumores intraorbitais mais comuns encontrados em adultos de meia-idade. Embora histológico benigno, eles podem invadir a área orbital ou intraorbital ou ainda as estruturas adjacentes (nervo óptico) e ser considerado anatomicamente ou posicional maligno. Apresentamos um relato de caso de hemangioma cavernoso orbital da órbita direita em mulheres jovens após a gravidez, a partir de Topola perto Kragujevac (Central Sérvia), com comprometimento visual e medicado por tratamento cirúrgico endoscópico transnasal. O paciente foi controlado e tratado com terapia, terapia tópica sintomático de lágrimas artificiais e tratamento cirúrgico. Nosso paciente tem acuidade visual ideal do olho direito afetada após o tratamento cirúrgico de tumor orbital. O tratamento cirúrgico do sintomático hemangioma cavernoso orbital é segura e eficaz, de modo que os resultados cosméticos são o parâmetro importante para avaliar o resultado clínico.

The method of moments (MoM) has been established as a powerful general tool for discretizing integral equations arising in numerical analysis of radiating and scattering structures. In MoM techniques based on the volume integral equation (VIE) approach, a structure is represented by a distribution of unknown volume polarization and conduction currents radiating in free space. MoM techniques based on the surface integral equation (SIE) approach treat electric and magnetic equivalent surface currents as unknowns in the numerical process. However, one general way to enhance the practical applicability and efficiency of both the MoM-VIE and MoM-SIE techniques is by means of the diakoptic method (E. Chobanyan, D. I. Olcan, M. M. Ilic, and B. M. Notaros, “Combining Diakoptic, VIE-MoM, and SIE-MoM Approaches in Analysis of Dielectric Scatterers,” Proc. 2013 IEEE Antennas and Propagation Society International Symposium).

♦ Objective Uremia is known to be followed by changes in the serous membranes of pleura, pericardium, and peritoneum. During continuous ambulatory peritoneal dialysis (CAPD), the peritoneum is exposed to altered body conditions as well as to the influence of dialysate. The aim of the present study was to examine the ultrastructure of the mesothelial cells in CAPD patients, and to compare the findings with those from studies of the peritoneum in uremic controls. Paracrystalline intracytoplasmic inclusions in mesothelial cells were objects of special interest. ♦ Methods Biopsies of human parietal peritoneum were studied. These were taken from 12 uremic patients during catheter implantation before the start of CAPD, and from 7 CAPD patients during catheter removal for infection or malfunction. The samples were prepared in the standard way to be studied by transmission electron microscopy (TEM). ♦ Results Paracrystalline intracytoplasmic inclusions were seen in mesothelial cells only by TEM. They appear as filamentous structures at the outer part of the inclusions, and as pearl-like structures at the core of the inclusions. Sacculate dilatations of rough endoplasmic reticulum cisternae with partly destroyed membranes and only few ribosomes were also seen, with and without densely osmiophilic filaments within the cisternae. We have found paracrystalline intracytoplasmic inclusions in mesothelial cells from uremic and CAPD patients both. According to the literature, these changes are present in one third of biopsies from uremic patients. Until now, however, they have not been mentioned in CAPD patients.

We present a model of human body for full-wave numerical analysis of contact electrostatic discharge. The model is based on frequency-dependent surface resistance distributed over the surface of the body, which models the measured parameters of human tissue. The numerical analysis is done by method of moments with surface integral-equation formulation in the frequency domain. The results for currents and fields in time domain are obtained using discrete (inverse) Fourier transform and frequency-domain data. The flexibility of the proposed model is tested and discussed by comparing the numerical results to the standard waveform of current in electrostatic discharge. The results for magnetic field, in the vicinity of the discharge, are compared to those found in the literature. The model predicts correctly both waveforms and peak values for currents and magnetic fields.

A diakoptic technique combining the finite element method (FEM) and the method of moments (MoM), and using dual sets of higher order basis functions is proposed for analysis of 3D electromagnetic radiation and scattering structures. These bases enable efficient modeling and significant reductions in the total number of unknowns, while satisfying the natural relation between curl-conforming and divergence-conforming quantities when closing the FEM domain by a MoM surface. The new diakoptic FEM-MoM technique is validated in an example of an array of 4×4 dielectrically coated spherical metallic scatterers.

We quantify the discrepancy between radar cross section (RCS) of long cylindrical scatterers and RCS of infinite structure with the same cross-section. The scatterers are made of perfect electric conductor and are excited so that vector of electric field is perpendicular to the cylinder axis. We use method of moments (MoM) for numerical analysis. The results show that if the cylinder is longer than 10 wavelengths, the 3-D RCS can be predicted with mean squared discrepancy less than 1 dB using 2-D analysis.

We outline an algorithm for block-sparse GPU accelerated out-of-core solver. The algorithm takes advantage of the block-sparsity that exists in method of moment analysis of composite electromagnetic systems with multiple materials. The efficiently of the proposed algorithm is demonstrated on the example of Luneburg lenses up to 40 wavelengths diameter. The approach yields speedup of up to 8 times, compared to general-purpose GPU accelerated out-of-core solver.

Forenzična genetika: Teorija i aplikacija

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.

Background There are three kinds of allosteric modulators acting through the benzodiazepine (BZ) binding site of the GABAA receptor: positive (agonist), neutral (antagonist), and negative (inverse agonist) modulators. Agonists and inverse agonists commonly exert bidirectional influences on observed behavioral parameters. In the present study we have investigated the modulation of behavioral responses to environmental novelty in two unconditioned paradigms: spontaneous locomotor activity (SLA) and forced swim test (FST), elicited by DMCM (methyl-6,7dimethoxy-4-ethyl-beta-carboline-3-carboxylate), a nonselective inverse agonist, in the dose range that previously did not produce anxiogenic effects and convulsions.

We present comparison of Differential evolution and Cuckoo search for optimization of linear antenna array of Hertzian dipoles. The amplitudes of excitations are optimized in order to minimize sidelobe levels. The results are compared for 42 elements array, with 20 optimization variables. The conclusion is that classic Differential evolution provides better convergence for this particular problem than standard Cuckoo search.

Full wave analysis of arbitrary structures in frequency domain is presented, as applied in WIPL-D Pro, software for 3D EM simulation. Currents induced over metallic structures and equivalent currents placed over material boundaries are found by solving electric field integral equation (EFIE) and PMCHW integral equations, respectively. High efficiency of the method is achieved by a) combining the Galerkin testing with higher order bases to obtain the symmetrical matrix equation of reduced size, and b) parallelization performed at CPU and/or GPU, for matrix fill and incore or out-of-core matrix solution.

We increase the computation and memory capabilities of GPU in-core solver by using block LU decomposition, RAM for storing the whole matrix and VRAM for storing currently used block(s) of data. Using up to 3 GPUs gives parallelization efficiency of up to 70%. The matrix of EM problems with 50 000 unknowns can be LU decomposed within 4 minutes on a PC with used GPUs.

Kardiovaskularne bolesti (KVB) su vodeca grupa bolesti, narocito u razvijenom svetu sa vise od milijardu obolelih i preko 40% svih uzroka smrti radno aktivnog stanovnistva. U toj grupi arterijska hipertenzija (HTA) zauzima prvo mesto kao najmasovnija nezarazna bolest covecanstva (World Hypertension League) . Arterijska hipertenzija jedno je od najopasnijih masovnih oboljenja modernog doba, sa znacajnim mortalitetom i invaliditetom i nemerljivim socijalnim posledicama u svetu i kod nas. U populaciji iznad 20 godina starosti ona je zastupljena cak kod 10–20% slucajeva. Cesto HTA protice decenijama asimptomatski, neotkrivena klinicki („tihi ubica“) koju demaskira neka od cesto fatalnih komplikacija: moždani udar, infarkt miokarda, akutna srcana insuficijencija, iznenadna smrt itd. . Veliki je broj etioloskih faktora koji uticu na pojavu esencijalne arterijske hipertenzije. U savremenom dobu nezaobilazni pratilac svih tokova razvoja civilizacije je stres i on postaje sve bitniji faktor uticaja na zdravstveno stanje stanovnistva. Tesko je proceniti koliki je stepen uticaja stresa pre svega zbog njegove kvantitativne, ali i kvalitativne nemerljivosti. Međutim, mnoge nedoumice na pocetku 21. veka možda ce izbaciti pitanje uticaja stresa i pitanje njegove kontrole u prvi plan. Esencijalna HTA definitivno je kompleksan metabolickohipertenzivnoarteriosklerotski sindrom sa visokim intraarterijskim pritiskom kao osnovnom karakteristikom. U njemu se preplicu razni metabolicki poremecaji, a udruženi sa određenim strukturnim promenama rezultiraju ubrzanom aterosklerozom i disfunkcijom ciljnih organa . Evropske (Europen Society of Hypertension – ESH i Europen Society of Cardiology – ESC) i americke preporuke (Joint National Committee – JNC VII) razlikuju se u vezi definicije i klasifikacije hipertenzije (tabele 1 i 2). Stres se može opisati kao fizicka i psihicka reakcija organizma na svaki potencijalno stetan faktor. Stres je stanje dugotrajne napetosti usled koje se javljaju fizioloske, psihosomatske reakcije cija je posledica pogorsavanje zdravstvenog stanja, osecaj frustracije, mentalna i fizicka iscrpljenost . Reakcija stresa je opsta, nespecificna, stereotipna i odvija se preko hipotalamohipofiznoadrenalne osovine sa porastom kortikosteroida u plazmi i kao takav stres je celovit biopsihosocijalni odgovor organizma na ugrožavanje i narusavanje njegove homeostaze . Na osnovu ukrstanja navedenih patofizioloskih mehanizama nastanka hipertenzije i stresa nije tesko zakljuciti da između ova dva stanja postoji izvesna uzrocno-posledicna veza. Shodno navedenom, u poslednje vreme sve cesce se u anglosaksonskoj medicini srecemo sa hipertenzijom uzrokovanom stresom (stress induced hypertension) kao posebnim klinickim entitetom.

25th ECNP Congress 13-17 October 2012 • Vienna, Austria Basic and clinical neuroscience – Animal behaviour

We compare results for EM transients calculated using frequency domain analysis coupled with FFT with and without frequency-domain rational-function interpolation, in order to reduce the total number of frequency samples needed for accurate calculation of transients. To further reduce the total analysis time, we use zero-padding, for all frequencies where excitation spectrum is negligible. The proposed approach is applied to a problem of finding transient EM fields within metallic resonator with high Q-factor. The presented results show that time-domain response can be calculated more efficiently, with preserving the overall accuracy, if the proposed rational-function interpolation in frequency domain is used.

We present acceleration for numerical solving of electromagnetic (EM) problems by using method of moments (MoM) and NVIDIA graphics processing units (GPU). Three stages of MoM are accelerated: matrix fill, solution of complex linear equations and post-processing. The results show that GPUs can be efficiently used for EM simulations.

The paper presents efficient technique for full wave 3D EM modeling of electrically large arrays. Basically it consists in two steps: 1) the network parameters (Y,Z,S) of the array are calculated together with its radiation patterns when each of the elements is active, while all other elements are short-circuited; 2) radiation patterns are obtained by arbitrary combinations of feeding voltages by post-processing data from the first step. 3D EM modeling is facilitated decomposing the problem having geometrical symmetry and asymmetrical excitation into four fully symmetrical problems of quarter size. Matrix solution is accelerated using graphical processor unit (GPU). Thus, array problems of 400 and 900 microstrip patch antennas become doable in 6 hours and 1 day, respectively.

We present results for frequency-domain MoM simulations of electrically large structures using out-of-core solver accelerated with multiple GPUs on a single personal computer. The structures analyzed in order to demonstrate the efficiency of proposed out-of-core solver are Cassegrain reflector antenna with up to 240 λ reflector diameter and Luneburg lens, up to 16 λ diameter, excited with a half-wavelength dipole. The acceleration of out-of-core solver is up to 10 times with one GPU compared to a standard CPU, or up to 20 times when using 3 GPUs.

By using the WIPL-D Time Domain Solver (TDS) to analyze the performance of the unloaded ice cream cone monopole (ICC) and the resistively loaded cone RC, it is shown that the ICC offers higher efficiency without the complications of resistive loading. It was also shown that the pulse response was improved by using a less abrupt junction at the interface between the coaxial line and the ground plane.

The principal objective of the work presented here is to demonstrate the proof-of-concept of coupling a higher-order finite element method (FEM) with a higher-order surface integral equation (SIE) method of moments (MoM) using the diakoptic approach. The diakoptic MoM-SIE approach has been successfully used for the electromagnetic (EM) analysis of microwave transmission lines, large scatterers, and antenna arrays [1], [2]. The diakoptic approach in this work uses coefficients calculated by a higher-order FEM code [3] and a higher-order MoM code [4], [5], and combines them to obtain the solution of the original EM problem. We briefly present the theory behind the concept and results for a case where the proposed approach is successfully applied with some diakoptic subsystems being solved using the FEM and the others using the MoM-SIE formulation.

Diakoptic surface integral-equation formulation is used to efficiently simulate large antenna arrays, modeled as 3D EM structures. The significant accelerations and storage reductions are achieved, when compared to the classical MoM-SIE. Both near field and far field (radiation pattern) of the arrays, calculated using DSIE, match the results calculated using MoM-SIE very well (the maximal relative error is about 1% calculated with respect to peak values). The future work will include diakoptic boundaries with common walls, application of DSIE to optimization of complex EM structures and calculation of EM time-domain responses, and hybridization with other numerical techniques such as finite elements and volume integral-equation formulation.

Modern design procedure of antennas, microwave components and EMC facilities usually includes full wave analysis of composite metallic and dielectric structures in frequency domain. One of the methods that can be used for such full wave analysis is method of moments (MoM) applied to surface integral equations (SIEs).

21st Congress of the European-College-of-Neuropsychopharmacology 2008, Barcelona Poster sessions Basic and clinical neuroscience – Cognitive neuroscience

The canonical particle swarm optimization (PSO) algorithm is known to be very good solution for EM optimization problems. In this paper we present results for a few modifications of the PSO algorithm (fully informed PSO algorithm and repeated PSO algorithm) when they are applied to the optimization of a broadside antenna array. The aim is to find out if and under what circumstances these modifications can give better results than the canonical PSO algorithm. According to obtained results, the well set-up canonical PSO algorithm (with appropriately chosen parameters), outperforms its modifications for EM optimization problems. The number of particles in the swarm seems to be proportional to both the number of dimensions of the optimization problem and the number of iterations.

The improvement of the efficiency of the time-domain analysis using frequency-domain response and the Fourier transform is achieved by adjusting the current expansion at each frequency and by interpolating the results in the frequency domain. The future work will include investigation of the minimal number of frequency samples needed for the interpolation, a non-uniform sampling in the frequency domain and the search for the optimal interpolation technique.

We investigate uniformly-wound helical antennas above ground conductors of various shapes, with aim to determine factors that improve the antenna radiation pattern and gain. We show that the characteristics of helical antennas with large spillover fields can be improved using ground conductors (reflectors). This is achieved by intercepting unwanted radiation and redirecting it favorably. (8 pages)

A diakoptic surface integral-equation formulation is applied to 2-D transversal magnetic (TM) scattering problems. The diakoptic formulation is based on the equivalence (Huygens') principle. The aim of the diakoptic formulation is to reduce the CPU time needed for the electromagnetic analysis and the memory needed for the data storage without compromising the final results. The proposed diakoptic formulation is illustrated on two examples of 2-D TM scatterers. The calculated radar cross-section (RCS), CPU time, and storage requirements are compared to those of the classic method of moments (MoM). (7 pages)

We present an efficient and accurate approach for calculating time-domain responses of antennas mounted on electrically large platforms, such as airplanes, spacecrafts, ships, tanks, etc. The approach is based on the proficient frequency-domain analysis coupled with the inverse Fourier transform, in order to obtain time-domain responses. For the basic frequency-domain analysis we use method of moments (MoM) with higher-order basis functions and Galerkin testing procedure [3], incorporated in the WIPL-D Pro software package. If the analyzed antenna is mounted on the large platform the rigorous MoM analysis needs a lot of computer resources. However, the number of unknown coefficients for the approximation of the current distribution, needed in the frequency analysis, can be drastically reduced without loosing the accuracy significantly [4]. We utilize that fact for the calculation of time-domain responses. (6 pages)

We present a numerically efficient technique for simulating RCS from trees and forests. Furthermore, we included other objects positioned (potentially hidden) in forests and the finite real ground below. The exploration of forest density, real finite ground plane, and operating frequency is done. The software tool WIPL-D Pro v6.0 is used for all simulations.

This paper presents optimization of a helical antenna with a truncated-cone reflector. We have found that the dimensions of the truncated-cone reflector and the dimensions of the helical antenna need to be optimized simultaneously to obtain the optimal design. Furthermore, we have found that the truncated-cone reflector can significantly increase the gain of the helical antenna compared to a circular or a square flat reflector. A set of diagrams is made to enable simple design of helical antennas with truncated-cone reflectors. Finally, the results are experimentally verified.