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In this work, we demonstrate the high efficiency of optical emission spectroscopy to estimate the etching profile of silicon structures in SF6/C4F8/O2 plasma. The etching profile is evaluated as a ratio of the emission intensity of the oxygen line (778.1 nm) to the fluorine lines (685.8 nm and 703.9 nm). It was found that for the creation of directional structures with line sizes from 13 to 100 µm and aspect ratio from ≈ 0.15 to ≈ 5 the optimal intensities ratio is in the range of 2-6, and for structures from 400 to 4000 µm with aspect ratio from ≈ 0.03 to ≈ 0.37 it is in the range 1.5-2. Moreover, the influence of the process parameters on the etching rate of silicon, the etching rate of aluminum, the inclination angle of the profile wall of the etched window, the selectivity of silicon etching with respect to aluminum, and the influence on the overetching (Bowing effect) of the structure was investigated.

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According to global data, there is a male reproductive potential decrease. Pathogenesis of male infertility is often associated with autoimmunity towards sperm antigens essential for fertilization. Antisperm autoantibodies (ASAs) have immobilizing and cytotoxic properties, impairing spermatogenesis, causing sperm agglutination, altering spermatozoa motility and acrosomal reaction, and thus preventing ovum fertilization. Infertility diagnosis requires a mandatory check for the ASAs. The concept of the blood-testis barrier is currently re-formulated, with an emphasis on informational paracrine and juxtacrine effects, rather than simple anatomical separation. The etiology of male infertility includes both autoimmune and non-autoimmune diseases but equally develops through autoimmune links of pathogenesis. Varicocele commonly leads to infertility due to testicular ischemic damage, venous stasis, local hyperthermia, and hypoandrogenism. However, varicocelectomy can alter the blood-testis barrier, facilitating ASAs production as well. There are contradictory data on the role of ASAs in the pathogenesis of varicocele-related infertility. Infection and inflammation both promote ASAs production due to "danger concept" mechanisms and because of antigen mimicry. Systemic pro-autoimmune influences like hyperprolactinemia, hypoandrogenism, and hypothyroidism also facilitate ASAs production. The diagnostic value of various ASAs has not yet been clearly attributed, and their cut-levels have not been determined in sera nor in ejaculate. The assessment of the autoimmunity role in the pathogenesis of male infertility is ambiguous, so the purpose of this review is to show the effects of ASAs on the pathogenesis of male infertility.

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The hippocampal theta rhythm (4-12 Hz) is one of the most important electrophysiological processes in the hippocampus, it participates in cognitive hippocampal functions, such as navigation in space, novelty detection, and declarative memory. We use neural network modeling to study the mechanism of theta rhythm emergence in the CA1 microcircuitry. Our model of the CA1 field includes biophysical representation of major cell types related to the theta rhythm emergence: excitatory pyramidal cells and two types of inhibitory interneurons, PV+ basket cells and oriens lacunosum-moleculare (OLM) cells. The main inputs to the CA1 cells come from the entorhinal cortex via perforant pathway, the CA3 field via Schaffer collaterals, and the medial septum via fimbria-fornix. By computer simulations we investigated the influence of each input, intrinsic parameters of neurons, and connections between neurons on phase coupling between the theta rhythm and the firing of pyramidal, PV+ basket and OLM cells in the CA1. We found that the input from the CA3 field via Schaffercollaterals plays a major role in the formation of phase relations that have been observed in experiments in vivo. The direct input from the medial septum participates in the formation of proper phase relations, but it is not crucial for the production of the theta rhythm in CA1 neural populations.

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Archaeogenetic studies have described the formation of Eurasian 'steppe ancestry' as a mixture of Eastern and Caucasus hunter-gatherers. However, it remains unclear when and where this ancestry arose and whether it was related to a horizon of cultural innovations in the 4th millennium BCE that subsequently facilitated the advance of pastoral societies in Eurasia. Here we generated genome-wide SNP data from 45 prehistoric individuals along a 3000-year temporal transect in the North Caucasus. We observe a genetic separation between the groups of the Caucasus and those of the adjacent steppe. The northern Caucasus groups are genetically similar to contemporaneous populations south of it, suggesting human movement across the mountain range during the Bronze Age. The steppe groups from Yamnaya and subsequent pastoralist cultures show evidence for previously undetected farmer-related ancestry from different contact zones, while Steppe Maykop individuals harbour additional Upper Palaeolithic Siberian and Native American related ancestry.

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We used stable water suspensions of copper oxide particles with mean diameter 20 nm and of particles containing copper oxide and element copper with mean diameter 340 nm to assess the pulmonary phagocytosis response of rats to a single intratracheal instillation of these suspensions using optical, transmission electron, and semi-contact atomic force microscopy and biochemical indices measured in the bronchoalveolar lavage fluid. Although both nano and submicron ultrafine particles were adversely bioactive, the former were found to be more toxic for lungs as compared with the latter while evoking more pronounced defense recruitment of alveolar macrophages and especially of neutrophil leukocytes and more active phagocytosis. Based on our results and literature data, we consider both copper solubilization and direct contact with cellular organelles (mainly, mitochondria) of persistent particles internalized by phagocytes as probable mechanisms of their cytotoxicity.

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Stable suspensions of nanogold (NG) and nanosilver (NS) with mean particle diameter 50 and 49 nm, respectively, were prepared by laser ablation of metals in water. To assess rat's pulmonary phagocytosis response to a single intratracheal instillation of these suspensions, we used optical, transmission electron, and semi-contact atomic force microscopy. NG and NS were also repeatedly injected intraperitoneally into rats at a dose of 10 mg/kg (0.5 mg per mL of deionized water) three times a week, up to 20 injections. A group of rats was thus injected with NS after oral administration of a "bioprotective complex" (BPC) comprised of pectin, multivitamins, some amino acids, calcium, selenium, and omega-3 PUFA. After the termination of the injections, many functional and biochemical indices and histopathological features of the spleen, kidneys and liver were evaluated for signs of toxicity, and accumulation of NG or NS in these organs was measured. From the same rats, we obtained cell suspensions of different tissues for performing the RAPD test. It was demonstrated that, although both nanometals were adversely bioactive in all respects considered in this study, NS was more noxious as compared with NG, and that the BPC tested by us attenuated both the toxicity and genotoxicity of NS.

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UNLABELLED: The aim is to perform our eight-year experience on prenatal (matemal) screening for Down syndrome (DS). METHODS: Pregnant women underwent screening in second trimester (ST2) - 14(+4)-19(+3) gestational week using serum AFP and free beta-hCG biochemical markers. A more sensitive first trimester test has been implemented in 11(+0)-13(+6) gestational weeks since the end of 2009. This combined screening test (CST1) was based on US measurements of NT (nuchal translucency) and NB (nasal bones) supplemented by biochemical markers of serum free beta-hCG and PAPP-A. Uniform methodology, web-based software and system for laboratory quality control had been used. False positive ratios for DS were estimated at cut-offs 1/250 for Down syndrome and 1/100 for Edwards syndrome. RESULTS: The test was performed on 17 468 pregnant women: 13 016 by biochemical screening 2 test (BHS2) and 4452 by first trimester test CST1. High risk for a chromosome disorder by BHS2 test was found in 1097 (8,4%) cases (5,96% < 35 years and 21,13% > 35 years). 7 fetuses were diagnosed with chromosome disease (5 fetuses with trisomy 21,1 - trisomy 18 and 1 - triploid); false positive were 1090 (8,4%). High risk for a chromosome disorder by CST1 test was found in 102 (2,3%) cases. 4 affected fetuses were diagnosed (3 with trisomy 21 and 1 with trisomy 13). Verified diagnosis for DS by first and second trimester tests were 43% (3 out of 7 cases) with 57% false negative results and 45,5% (6 out of 11 cases) with 54,5% false negative results respectively. Description of biochemical values/MoMs and US measurements are applied. CONCLUSIONS: We comment on the importance of US measurements in CST1 test and correct analysis of biochemical and US markers in counseling of every individual patient, beyond final risk number.

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UNLABELLED: Performance of 2,5 year experience onprenatal (maternal) screening by integrated risk for Down syndrome and Edwards syndrome is presented in pregnant women underwent first (11(+0)-13(+6) g.w) and second trimester screening (14(+4)-19(+3) g.w), assessed by an integrated risk. Since the end of 2010 the most common strategy has been combination of both risks after contingent screening approach (serummarkers and US measurments from first test with indication to second trimester screening if the risk is intermediate or high and CVS diagnosis has been refused). Serummarkers were measured by fluorimetric immunoassay (Delfia) and risks were calculated using LifeCycle 3.2 software. RESULTS: The test was performed on 491 women, less than 4452 and 13 016 women first and second trimester respectively. We found highrisk for a chromosome disorder in 32 (6,5%) cases: 19 (6,35%) women < 35 and 13 (6,7%) women > 35). Diagnosis of a chromosome diseases was found in 4 fetuses out of 32 (12,5%): 3 fetuses with trisomy 21 and 1 with trisomy 18. False positive results were found in 28 out of 491 (5,7%) women. Verified diagnosis on lyfor DS was found in 3 out of 4 cases (75% sensitivity), and false negative results in 25%. Discussion is focused on the comparison of the screening approaches - the sensitivity, limitation sand the step wise sequential testing way with integrated risk of achieving a high performance of screening.

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The aim of this report is to present and discuss the results from diagnostic amniocenteses, performed in Varna. The test started as a part of a prophylaxis program for pregnant women with calculated high risk for chromosomal disorders after a screening test. Amniocentesis was performed in total of 283 pregnant women. Of all patients who underwent the screening test, amniocentesis was performed in 1.55% of women under 36 years of age and 5.0% of women over 36 years. In the selected group with calculated high risk for chromosomal disorder these percentages were 28.5% and 26% respectively. Fetal chromosomal disorder was found in 5% (in 7 out of 141) in women under 36 and 3.82% (in 7 out of 83) in women over 36 years. Genetic tests (DNA and cytogenetic analysis) of amniocytes revealed chromosomal disorders in 16 (5.65%) fetuses (8 with trisomy 21, 3 with trisomy 18, 1 with trisomy 13, 1 case with triploidy, 3 cases with structural chromosomal rearrangement). Three additional amniocenteses were performed, indicated by family history of monogenic disorder (thalassaemia, spinal muscular atrophy). The effect of the introduced method for prenatal diagnosis, its interaction with the screening tests and their future as genetic prophylaxis program are discussed.

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We consider the problem of what is being optimized in human actions with respect to various aspects of human movements and different motor tasks. From the mathematical point of view this problem consists of finding an unknown objective function given the values at which it reaches its minimum. This problem is called the inverse optimization problem. Until now the main approach to this problems has been the cut-and-try method, which consists of introducing an objective function and checking how it reflects the experimental data. Using this approach, different objective functions have been proposed for the same motor action. In the current paper we focus on inverse optimization problems with additive objective functions and linear constraints. Such problems are typical in human movement science. The problem of muscle (or finger) force sharing is an example. For such problems we obtain sufficient conditions for uniqueness and propose a method for determining the objective functions. To illustrate our method we analyze the problem of force sharing among the fingers in a grasping task. We estimate the objective function from the experimental data and show that it can predict the force-sharing pattern for a vast range of external forces and torques applied to the grasped object. The resulting objective function is quadratic with essentially non-zero linear terms.

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We develop a new oscillatory model that combines consecutive selection of objects and discrimination between new and familiar objects. The model works with visual information and fulfils the following operations: (1) separation of different objects according to their spatial connectivity; (2) consecutive selection of objects located in the visual field into the attention focus; (3) extraction of features; (4) representation of objects in working memory; (5) novelty detection of objects. The functioning of the model is based on two main principles: the synchronization of oscillators through phase-locking and resonant increase of the amplitudes of oscillators if they work in-phase with other oscillators. The results of computer simulation of the model are described for visual stimuli representing printed words.

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A new mechanism to control attention focus formation and switching in the model of selective attention is suggested and studied. The model is based on an oscillatory neural network (ONN) with the star-like architecture and phase shifts in connections between oscillators. Attention is modelled as a dynamical mode of partial synchronisation between a particular subgroup of oscillators and the central oscillator (CO). A new theoretical method to study full and partial synchronisation in the system is presented. Equations for the frequency of synchronisation are derived which allow the programming of the dynamical behaviour of the system depending on the parameters. In particular, we show that phase shifts in connections between oscillators provide an efficient mechanism of attention control.

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