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Temporal leakage occurs when the time-domain response of a linear electromagnetic system is computed from frequency-domain data using the inverse discrete Fourier transform. Although the temporal leakage occurs in most practical cases, this phenomenon is not recognized in the literature covering electromagnetics, antennas, and microwaves. The purpose of the paper is to demonstrate and explain the temporal leakage. [ABSTRACT FROM AUTHOR]

The method of moments (MoM), applied to surface integral equations (SIEs) in the frequency domain, enables very accurate analysis of composite metallic and dielectric structures. Particularly, on a desktop PC, the electrical size of solvable problems is very limited by memory and time resources. This limit can be significantly extended by using advanced techniques, which are shortly revealed. The focus of the paper is to present results that illustrate current possibilities of MoM/SIEs solution on a desktop PC: (1) monostatic RCS of a cube of side 80 λ, (2) beam steering of an array of 30 by 30 microstrip patch antennas at 9.2 GHz, and (3) beam steering of 4 by 4 patch antennas at 5 GHz, placed on a 19 m long helicopter. [ABSTRACT FROM AUTHOR]

In Romania there is one of most powerful seismic activity region from Europe, known as Vrancea. In the past 300 years, a single major seismic event occurred with an epicenter outside this area (1916). This paper starts from going over all major seismic events, with a magnitude of over 6 degrees on Richter's scale, which were documented. Was tested the most plausible statistic behavioral model and was determined the probabilities for future large scale earthquakes, by different time horizons. [ABSTRACT FROM AUTHOR]

This article investigates the influence of milling process on properties of printed microwave circuits. Furthermore, design guidelines are proposed for optimizing the milling process by leaving large unmilled copper surfaces on the board without deteriorating circuit performance. The proposed concepts are experimentally verified. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:264-270, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25724 [ABSTRACT FROM AUTHOR]

The present paper examines the failure criteria of layered composites with orthotropic properties in the homogeneous temperature field. The composite has modeled by two mechanically equivalent families of fibres. The paper formulates constitutive equations in terms of intrinsic "preferred" directions, which are defined by the orientation of fibers at any point of the composite. A uniformly heated, thermoelastic solid undergoes distortion as well as volume change because it experiences differential expansions in different directions. This effect is more complicated if, in addition of being anisotropic, the material is inhomogeneous, as in the case with laminated materials. In order to illustrate the influence of temperature on the failure of this group of materials constitutive equations are derived and adopted for use in failure criteria, without the influence of temperatures, and with the influence of increased temperature. [ABSTRACT FROM AUTHOR]

Analysis of output quality of power transmitters is possible in position when characteristics are determined earlier. This is the reason why we focused on determination of these characteristics for a concrete power hydro-transmitter. This means that the investigation task primarily consisted of determination of functional characteristics, defining of the sliding curves and temperature regimes of a concrete hydrodynamic clutch. Results of velocity and pressure field investigations in the working space of this clutch, obtained by use of the same test setup, are the basis for determination and analysis of the functional characteristics, sliding curves and temperature regimes. In this work we also analyzed function of the hydrodynamic transmitter in assembly with an internal combustion engine, as well as a process of acceleration and deceleration of a vehicle with this assembly in it. [ABSTRACT FROM AUTHOR]

This paper studies problems of hard facing of damaged and initially cracked mechanical engineering heavy parts of complex geometry such as large rams of air powered drop hammers. During long-term exploitation, these parts are subjected to thermal fatigue due to cyclic temperature changes and variable impact compression. Taking into consideration high ram costs and difficulties to purchase ram, the necessity of its reparation becomes obvious. The choices of the most suitable technologies of hard facing and welding of an initially cracked ram are also studied here. Besides the techno-economic analysis, an energetic analysis is performed as an additional criterion in assessment of the proposed technology. [ABSTRACT FROM AUTHOR]

Classical benzodiazepines (BZs) exert anxiolytic, sedative, hypnotic, muscle relaxant, anticonvulsive, and amnesic effects through potentiation of neurotransmission at GABAA receptors containing α1, α2, α3 or α5 subunits. Genetic studies suggest that modulation at the α1 subunit contributes to much of the adverse effects of BZs, most notably sedation, ataxia, and amnesia. Hence, BZ site ligands functionally inactive at GABAA receptors containing the α1 subunit are considered to be promising leads for novel, anxioselective anxiolytics devoid of sedative properties. In pursuing this approach, we used two-electrode voltage clamp experiments in Xenopus oocytes expressing recombinant GABAA receptor subtypes to investigate functional selectivity of three newly synthesized BZ site ligands and also compared their in vivo behavioral profiles. The compounds were functionally selective for α2-, α3-, and α5-containing subtypes of GABAA receptors (SH-053-S-CH3 and SH-053-S-CH3-2′F) or essentially selective for α5 subtypes (SH-053-R-CH3). Possible influences on behavioral measures were tested in the elevated plus maze, spontaneous locomotor activity, and rotarod test, which are considered primarily predictive of the anxiolytic, sedative, and ataxic influence of BZs, respectively. The results confirmed the substantially diminished ataxic potential of BZ site agonists devoid of α1 subunit-mediated effects, with preserved anti-anxiety effects at 30 mg/kg of SH-053-S-CH3 and SH-053-S-CH3-2′F. However, all three ligands, dosed at 30 mg/kg, decreased spontaneous locomotor activity, suggesting that sedation may be partly dependent on activity mediated by α5-containing GABAA receptors. Hence, it could be of importance to avoid substantial agonist activity at α5 receptors by candidate anxioselective anxiolytics, if clinical sedation is to be avoided.Neuropsychopharmacology (2008) 33, 332–339; doi:10.1038/sj.npp.1301403; published online 28 March 2007 [ABSTRACT FROM AUTHOR]

Abstract: In the previous study of the rat frontal cortex slices oxygen consumption (QO2), polarographically determined using the biological oxygen monitor, a moderate respiratory depressant action of midazolam ex vivo (1.0mg/kg) has been observed. Antagonist of the benzodiazepine binding site, flumazenil, blocked the effect of the agonist. However, midazolam–γ-aminobutyric acid (GABA) interactions pointed to the possibility that a part of midazolam action is independent of the classical GABA potentiation. To test this presumption, GABAA receptor antagonists bicuculline and picrotoxin were administered. Both blockers antagonized the QO2 reducing effect of the combination of per se effective doses of midazolam (1.0mg/kg) and GABA (5×10−4 mol/l), as well as of GABA (5×10−4 mol/l) itself. However, neither effects of midazolam (1.0mg/kg) on its own, nor those of midazolam in presence of the physiological, per se ineffective, concentration of GABA (10−6 mol/l), were susceptible to antagonism. These results show that ex vivo influence of midazolam on cerebral metabolic activity should be partly ascribed to some of its cellular mechanisms probably associated to the GABA modulation, but distinct from the standard GABA-potentiating effects of benzodiazepines. [Copyright &y& Elsevier]

Copyright of ZOR: Mathematical Methods of Operations Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

OP08.06: Assessing quality standards in measurement of uterine artery pulsatility index at 11 to 13+6 weeks of gestation, multicentric study To assess the quality of the measurement of the uterine artery pulsatility index (UtA-PI) at 11 to 13+6 gestational weeks, at the time of pre-eclampsia screening. Centres should routinely monitor the quality of UtA-PI measurements used to estimate the pre-eclampsia screening risk and should provide individualised feedback to sonographers of their measures of central tendency and dispersion to ensure consistent and improved performance. [Extracted from the article]

This paper proposes a method for efficient identification of instruction-dependent sources on a printed circuit board (PCB) by localizing magnetic field sources from a limited number of measurements around the PCB. We first excite the processor by generating an artificial leakage signal at a specific frequency that is directly related to processor instructions. Then, we collect all three components of the magnetic field, but only at locations around the edge of the board. Furthermore, we model these magnetic field sources and then solve a forward–backward optimization problem using the model and measured data to identify the locations of the magnetic field sources, the magnitudes of the moments, and their orientations. The localization results are first verified using simulations, then tested when noise is added to the simulation results, and finally verified against measurements on field-programmable gate array (FPGA) and internet of things (IoT) development boards. The results show that the number of strong magnetic field sources on a board depends on the instructions used to excite the board. Furthermore, the results show that the proposed localization algorithm can accurately identify those sources, regardless of the frequency at which the measurements are conducted and the instruction pairs that are executed. Finally, the proposed method can significantly reduce the number of measurement points and the time needed to identify magnetic field sources on a PCB. [ABSTRACT FROM PUBLISHER]

Various studies reported beneficial effects of dehydroepiandrosterone (DHEA) and its sulphate (DHEAS), the neurosteroids involved in various brain functions, on synaptic plasticity, neuronal survival, memory, learning and behavior. This study aimed to investigate the behavioral profile of acute DHEA treatment by using active avoidance (AA) task, primarily predictive of the effects on the retrieval-based learning, and by applying forced swim test (FST), for assessment of antidepressant-like potential. Adult male Wistar rats received intraperitoneal injections of either DHEA (2, 10, 20 mg/kg) or solvent, 30 min prior to testing. DHEA, in a manner resembling an inverted U shape, influenced the retrieval imposed to rats in AA paradigm. The significant improvement of the performance in the retention session was observed following 10 mg/kg DHEA treatment and it was not due to the changes in the motor activity, as indicated by unaltered locomotor parameters (inter-trial crossing). Moreover, 10 mg/kg of DHEA significantly decreased the duration of immobility in FST, demonstrating antidepressant-like effects. The capability of bicuculline (2 mg/kg) to antagonize the effects of DHEA has been evaluated simultaneously. The retrieval-facilitating as well as antidepressant-like effects of 10 mg/kg DHEA were counteracted by bicuculline, a competitive antagonist of GABA A receptors, suggesting involvement of GABAergic system. These results support administration of DHEA as potential therapeutic strategy for treating depression and related cognitive impairments, but emphasized the importance of adequate dosing, as DHEA levels that are too high or too low may not be beneficial. [ABSTRACT FROM AUTHOR]

A novel diakoptic method based on volume integral equation (VIE) modeling of subsystems is proposed for 3-D electromagnetic analysis. The theoretical foundation of the method is the surface and volume equivalence principles, as it combines the VIE and surface integral equation (SIE) formulations, in conjunction with the method of moments (MoM). The method breaks the original structure into a number of nonoverlapping closed-region subsystems that contain inhomogeneous dielectric materials and an open-region subsystem. Each subsystem is analyzed completely independently applying the double higher order large-domain Galerkin generalized MoM-VIE-SIE (VSIE) or MoM-SIE solvers. The final solution is obtained from diakoptic matrices expressing linear relations between the electric and magnetic equivalent surface current coefficients on diakoptic surfaces. The proposed VSIE-diakoptic method is validated, evaluated, and discussed in several characteristic examples. The examples demonstrate that the diakoptic method substantially increases the efficiency of the conventional MoM-VIE approach. When compared with the pure MoM-VIE double higher order technique, the diakoptic approach enables very considerable accelerations and memory savings, while fully preserving the accuracy of the analysis. [ABSTRACT FROM PUBLISHER]

Aim To determine correlation between central corneal thickness (CCT) and applanation intraocular pressure (IOP) in normal patients with primary open angle glaucoma and patients with ocular hypertension. Methods Two-year retrospective study designed to determine correlation between CCT and IOP. Records of 121, patients were included in the study. Inclusion criteria were: IOP higher than 22 mm Hg for a group with ocular hypertension but without functional, morphological damage and progression, diagnosis of glaucoma for a group with open-angle glaucoma and normal ophthalmological results for a control group. Patients who were mono-oculus, patients with secondary glaucoma and who had surgical treatment were excluded. The patients were selectively grouped according to types of glaucoma, by gender and age. The IOP values were measured by Goldman's applanation tonometer, CCT values were determined using ultrasonic pachymeter, in the period from January 2011 to December 2012. Results Of total 121 subjects, 51 had primary open angle glaucoma (POAG), 40 had ocular hypertension (OHT) and 30 had normal ophthalmological findings (control group). The CCT values in OHT group 529.37+/-25.18 µm were greater than of both POAG, 501.02+/-14.04 µm and control group, 497.37+/-14.90 gm. The IOP values in OHT group were 20.25+/- 3.62 mm Hg, and in POAG group were 18.25+/-2.70 mm Hg, while in the control group they were 13.53+/- 3.62 mm Hg. Conclusion Determination of CCT in patients with glaucoma is crucial, considering its impact on IOP values, which represents a parameter in glaucoma diagnosis, as well as monitoring further progress of ocular hypertension and patients diagnosed with glaucoma. [ABSTRACT FROM AUTHOR]

Abstract: There are several modulatory sites at GABAA receptors, which mediate the actions of many drugs, among them benzodiazepine. Three kinds of allosteric modulators act through the benzodiazepine binding site: positive (agonist), neutral (antagonist), and negative (inverse agonist). The goal of the present study was to examine the influence of the inverse agonist methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM) acting on α GABAA receptor and compare its dose-response effects on memory and depression-like behavior. We independently studied the effects of DMCM (0.05–1.0mg/kg) on retention versus acquisition of active avoidance and depression-like behavior in the forced swim test. Throughout the study, drugs were given intraperitoneally, 30min before testing. ANOVA has showed that treatment with DMCM significantly affected retrieval of avoidance response (p <0.05), exerted promnesic effects in inverted U-shape manner. Dunnett''s test indicated that the DMCM avoidance-facilitatory dose was 0.1mg/kg. At the dose facilitating retrieval of avoidance memory, DMCM significantly (p <0.05, comparison of regression coefficients by Student''s t-test) and progressively increased acquisition rate during 5 days training, compared to the saline group. In forced swim test, ANOVA indicated statistically significant effects of DMCM (p <0.05). Dunnett''s analysis showed that DMCM significantly decreased immobility time at the dose of 0.1mg/kg, exerted acute antidepressant-like effects. Our results experimentally support the findings that under certain circumstances, nonselective benzodiazepine site inverse agonists, produce memory-enhancing and antidepressant-like effects. The molecular and neuronal substrates linking the actions of specific GABA-benzodiazepine receptor complex subunits remains to be further elucidated. [Copyright &y& Elsevier]

Dental education is regarded as a complex, demanding and often stressful pedagogical procedure. Undergraduates, while enrolled in programmes of 4–6 years duration, are required to attain a unique and diverse collection of competences. Despite the major differences in educational systems, philosophies, methods and resources available worldwide, dental students’ views regarding their education appear to be relatively convergent. This paper summarizes dental students’ standpoint of their studies, showcases their experiences in different educational settings and discusses the characteristics of a positive academic environment. It is a consensus opinion that the ‘students’ perspective’ should be taken into consideration in all discussions and decisions regarding dental education. Moreover, it is suggested that the set of recommendations proposed can improve students’ quality of life and well-being, enhance their total educational experience and positively influence their future careers as oral health physicians. The ‘ideal’ academic environment may be defined as one that best prepares students for their future professional life and contributes towards their personal development, psychosomatic and social well-being. A number of diverse factors significantly influence the way students perceive and experience their education. These range from ‘class size’, ‘leisure time’ and ‘assessment procedures’ to ‘relations with peers and faculty’, ‘ethical climate’ and ‘extra-curricular opportunities’. Research has revealed that stress symptoms, including psychological and psychosomatic manifestations, are prevalent among dental students. Apparently some stressors are inherent in dental studies. Nevertheless, suggested strategies and preventive interventions can reduce or eliminate many sources of stress and appropriate support services should be readily available. A key point for the Working Group has been the discrimination between ‘teaching’ and ‘learning’. It is suggested that the educational content should be made available to students through a variety of methods, because individual learning styles and preferences vary considerably. Regardless of the educational philosophy adopted, students should be placed at the centre of the process. Moreover, it is critical that they are encouraged to take responsibility for their own learning. Other improvements suggested include increased formative assessment and self-assessment opportunities, reflective portfolios, collaborative learning, familiarization with and increased implementation of information and communication technology applications, early clinical exposure, greater emphasis on qualitative criteria in clinical education, community placements, and other extracurricular experiences such as international exchanges and awareness of minority and global health issues. The establishment of a global network in dental education is firmly supported but to be effective it will need active student representation and involvement. [ABSTRACT FROM AUTHOR]