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The article present the clinical observation of 4 year old boy with scrotal hypospadias. Previous surgery management had unsatisfactory results due to complications of the cyst of the prostatic utricle. Laparoscopic removal of the cyst of the prostatic utricle was performed. The next step was urethral plastic. The results of the operation were satisfactory. A brief review of the literature is provided.

Acoustic, optical, and acousto-optic properties of amorphous germanium-, selenium-, silicon-, and tellurium-based alloys have been studied. The velocities of longitudinal acoustic waves and acousto-optic figure of merit were measured for amorphous tellurium-based alloys at wavelength λ = 3.39 μm. Acousto-optic figure of merit of a germanium single crystal was studied under diffraction on longitudinal acoustic modes along the [110] and [111] crystal directions.

Empirical studies in democracies have revealed some degree of causal relationship between public opinion and foreign policy. A look at the relationship between the evolution of Russian foreign poli...

Attenuated total reflection infrared spectroscopy is used to determine the free charge carrier concentration in arrays of silicon nanowires with characteristic transverse sizes of 50–100 nm and a length of the order of 10 μm formed on lightly doped crystalline p-type silicon by metal-assisted chemical etching and subjected to the additional thermal-diffusion doping of boron at temperatures of 850–1000°C. It is found that the free hole concentration in arrays varies from 5 × 1018 to 3 × 1019 cm–3 depending on the annealing temperature and is maximal at temperatures of 900–950°C. These results can be used to extend the range of potential application of silicon nanowires in photonics, sensorics, and thermoelectric power converters.

This article aims at contributing to the current debate over the effects of illicit transnational activities on states. Recent avenues of conceptualizing transnational organized crime call for defining it as an economic activity with the scope of profit, rather than a criminal activity. Illicit transnational business activities largely follow the trends in development of legal business. The transnational criminal enterprises emerged in parallel to the growth of multinational corporations, making use of the same opportunities as legal business did. The article discusses violence by illicit enterprises and reviews current theoretical debate on the linkages between illicit enterprises and the state. The paper then proceeds with an empirical analysis of the effects of the presence of illicit enterprises on state weakness. We have hypothesized that weak states may have higher presence of criminal businesses. The findings generally confirm significant correlation between the two variables. State fragility is positively correlated with the presence of organized crime. Testing these results against empirical evidence partially confirms the findings. However, this correlation might be weakened by the observation that the presence of illicit enterprises alone does not determine state fragility or strength.

Semitransparent composites with glass microspheres are promising modern materials. In particular, they contribute to the increase of the efficiency of heat-insulating coatings. An experimental study of the transmission and scattering of infrared radiation (at wavelengths from 2 to 25 μm) by a sodium borosilicate glass microsphere powder is presented. The spectra, angular-scattering patterns, and the degree of polarization of scattered radiation were studied.

We report on the effect of phosphorus doping of silicon nanowires (SiNWs) on the photoinduced heating processes. SiNWs samples were prepared by metal-assisted chemical etching of low boron-doped crystalline silicon (c-Si) wafers followed with thermo-diffusional doping with phosphorous (P) up to 1020 cm-3. We establish that the P-doping (n-type) results in effective heat conduction along SiNWs toward the c-Si substrate during laser heating. Partial phase transition in P-doped SiNWs under intense photoheating was detected by means of Raman spectroscopy and photoluminescence. The observed doping effects were explained by a contribution of charge carriers (electrons) to the heat distribution along SiNWs and partial screening of the crystal lattice potential. The obtained results can be useful for the development of new photonic and optoelectronic devices based on SiNWs.

The infrared optical properties of anisotropic mesoporous silicon films containing free charge carriers (holes) are studied experimentally and theoretically. The results of simulation of the optical properties of the produced samples in the effective-medium approximation show a heavy dependence of the birefringence, reflection anisotropy, and dichroism on the concentration of free charge carriers. The unsteady behavior of the differential transmittance recorded for the samples at mutually perpendicular polarization directions of light are attributed to the effect of charge carriers with a concentration on the order of 1019 cm–3. The results of the study suggest that anisotropic silicon nanostructures are promising materials for infrared photonics and terahertz engineering.

Aim. To improve the long-term outcomes of patients with atrial fibrillation (AF) after cardioembolic stroke by creating and testing a comprehensive ambulatory monitoring system.Material and methods. The present study included 139 AF patients after cardioembolic stroke for the period 2016-2019, of which 80 (57,55%) were women and 59 (42,45%) were men. The mean age of the patients was 72,25±6,33years. Before the hospital discharge, all patients signed an informed consent and were randomized into two groups. Patients of the group I (n=72) were followed up during the year in accordance with a specially developed comprehensive ambulatory monitoring system. This system included a rehabilitation program created individually for each patient, monthly visits to a physician-researcher, during which a complex of diagnostic tests was carried out. Also, the changes of complaints, symptoms, and medical adherence were assessed. The latter was corrected. A physician talked with the patient's relatives about the need to comply with the recommended medication regimen, supporting the motivation for treatment. Patients of group II (n=67) were followed up at the primary care level in accordance with the current program, and a control visit to was performed for them once — after 12 months.Results. After one-year follow-up, a significant decrease in all-cause mortality was obtained in the first group in comparison with the second one: 3 (4,17%) and 18 (26,87%) deaths, respectively (p=0,021).In addition, in group II, a relationship was found between the death and absence of anticoagulant therapy (odds ratio, 7,68; 95% confidence interval, 1,59-37,03; p=0,01). The ROC analysis confirmed the relationship between the absence of anticoagulant therapy and death, while the regression quality was good (area under the curve, 0,77, sensitivity — 94,74%, specificity — 59,17%).Conclusion. Comprehensive ambulatory monitoring program for AF patients after cardioembolic stroke has proven high effectiveness, and its widespread practice is an urgent task of modern healthcare.

The advances of biomedicine include the new technologies, diagnosis and treatment techniques, as well as the practical use of new types of biological targets, in particular, nucleic acids. Genomic deoxyribonucleic acid (DNA), extracellular DNA (exDNA) and microbiome DNA obtained from different types of samples (tissues, blood and its derivatives, feces, etc.) are used as objects of genetic research. The use of new technologies for DNA analysis required the development of standardized methods for processing biological samples in order to obtain high-quality DNA samples. The research uses various methods for collecting, preparing samples and storing various DNA-containing biomaterials and isolated DNA, as well as methods for assessing the quality of samples and biobank standards. It is obvious that the use of uniform standards will allow large-scale genetic research on the basis of biobanks and research laboratories. Specialists from professional organizations such as International Society for Biological and Environmental Repositories (ISBER), Biobanking and BioMolecular Resources Research Infrastructure-European Research Infrastructure Consortium (BBMRI-ERIC), European, Middle Eastern & African Society for Biopreservationa and Biobanking (ESBB) and the Russian National Association of Biobanks and Biobanking Professionals.

Aberrant methylation of gene promoter regions is the main epigenetic change characterizing colorectal cancer. Methylation levels of 42 CpG-sites of promoter regions of the MGMT, APC and CDH13 genes in colorectal cancer were studied in comparison with methylation levels of the adjacent normal tissue in 25 patients. Pyrosequencing showed an increase in methylation levels of promoter regions of the MGMT, APC and CDH13 genes in tumor samples by 3 to 5 times. These tumor samples were screened for activating SNP-mutations in the KRAS (40 %), NRAS (0 %) and BRAF (0 %) oncogenes. SNP-mutations in the KRAS gene were accompanied by hypermethylation of one or more promoters of the studied genes. Association of this epigenetic index with tumor metastasis was proved. The data on an increase in methylation of the promoter regions of oncosupressor genes can be used as sensitive prognostic markers of progression and metastasis of colorectal cancer.

The feasibility of using Prevention-N-E, a newly developed and tested biological product, in comparison with the previously tested PS-6 preparation in the adaptive technology of keeping specialized beef cattle of imported breeding, had been scientifically substantiated and experimentally proved. Against the background of the use of drugs in animals of the 1st and 2nd experimental groups, the incidence of the digestive and respiratory organs decreased by 1.4 and 2.3 times, the recovery time reduced by 3.36 and 4.88 days, accordingly, compared with the control (P st and 2nd experimental groups exceeded in live weight control subjects by 6.6 and 9.2 kg, rearing by 10.4 and 14.8 kg, and fattening by 14.2 and 22.2 kg respectively. In the cuts of the carcasses of bulls of the 1st and 2nd experimental groups, there was a bigger amount of the highest grade flesh: in spin-breast – by 1.0 and 1.0 kg, in the lumbar – by 0.2 and 0.4 kg, and in the hip – by 2.3 and 4.2 kg, rather than in the control.

Arrays of silicon nanowires (SiNWs) of about 100 nm in diameter formed by metal-assisted chemical etching of crystalline silicon (c-Si) substrates were studied regarding efficiency of optical interactions in them. Strong scattering in the SiNW arrays results in enhanced photon lifetime in them, which was evidenced by measurement of the cross-correlation function for femtosecond pulses scattered by the SiNW arrays. This effect results in an order of magnitude growth of efficiency such processes as spontaneous Raman scattering and third-harmonic (TH) generation compared to the signals for c-Si. Using (110) oriented c-Si substrate we managed to make well-oriented tilted SiNWs demonstrating strongly anisotropy of the TH and coherent anti-Stokes Raman scattering signals. In particular, efficiencies of these processes differ significantly when incident radiation propagates along or perpendicular to the SINWs. The obtained results could be explained by variations of the local fields in SiNWs and scattering cross-section.

Burns (combustio) - tissue damage arising from thermal, chemical, electrical or radiation exposure. Burn disease – a complex violation of the organs and systems, developing due to extensive burns. The cause of burn disease is the loss of all types of the skin functions, loss of plasma, the collapse of red blood cells, as well as metabolic disorders. The probability of development, severity, and prognosis in this pathology are determined by the age of the patient, the General condition of his body and some other factors, but the leading role is played by the area of the lesion. 500 thousand animals are burned according to statistics in Russia for the year, and as a rule, mortality among burned animals is more than 11%. Treatment includes antibiotic therapy, infusion, and detoxification therapy, correction of all organs and systems. Treatment of burns of the first and second degree is most often limited to the local use of drugs that reduce pain sensitivity, promote faster tissue regeneration and help prevent infection, which leads to lengthening of healing processes and other complications. In the case of third and fourth-degree burns, regular thorough cleaning of the affected areas is also necessary, sometimes surgical intervention is required. Today, burns are widespread, so the search for effective treatments remains relevant. In this paper, we describe the etiology, pathogenesis of burns of small pets, the definition of the most effective and cost-effective method of treatment. The task of the research was also to determine the degree of burns and diagnosis of burns.

Silicon nanowire (SiNW) arrays formed by metal-assisted chemical etching of boron low-doped crystalline silicon (c-Si) substrates were studied regarding enhanced efficiency of optical interactions in them. Along with high diffuse reflection of the structures under study, Raman and third-harmonic signals exhibited an order of magnitude growth compared to c-Si response in the near-infrared spectral region. Changes in the orientation dependencies of the third-harmonic intensity with SiNW length increase promoted the explanation of the optical peculiarities of SiNW arrays. Cross-correlation of the scattered radiation function evidenced that the effects could be explained by enhanced photon lifetime inside mesoscopic structure of SiNW arrays due to multiple scattering. Hence a correlation between the photon lifetime and the Raman and third-harmonic efficiency in SiNWs was revealed.

In the article the calculation formulas for determination of unloadings (finishings loadings) of wheels and bendings of a spring suspension of 8-wheel electric locomotive DS 3 with the hauling transmission of the second kind at the transmission of tractive forces from the bogies to the body through sloping tractions are presented. Numerical calculations are executed on the example of mainline freight-and-passenger electric locomotive DS 3.

Artificial anisotropic optical media based on nanostructured silicon formed by electrochemical porosifying of Si substrates are investigated. Strong birefringence and dichroism of surface silicon-hydrogen bonds vibrations are found in the infrared spectral range. A comprehensive analysis of the absorption bands corresponding to the deformation and stretching modes is performed. The experimental results are discussed in terms of an effective medium model, taking into account the morphological anisotropy of Si nanocrystals in porous Si layers. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In-plane birefringent porous Si (PSi) layers formed from heavily boron-doped (110) Si wafers are investigated by using polarization-resolved infrared absorption (IR) spectroscopy. The absorption by free charge carriers and by Si-Hx (x = 1, 2, 3) surface bond vibrations are found to exhibit strong anisotropy (dichroism), which originates from the form anisotropy of Si nanocrystals assembling (110) PSi layers. The free carrier absorption dichroism is explained by using the effective medium approximation and classical Drude model and considering additional carrier scattering in anisotropically shaped Si nanocrystals. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Birefringence in porous silicon layers prepared with different etching currents on a (110) substrate is studied by IR Fourier spectroscopy. The spectra exhibit beats in the intensity of transmitted and reflected radiation due to the summation of the intensities of the ordinary and extraordinary waves interfering in the porous layer. An analysis of the spectra shows the layers to exhibit properties of a negative uniaxial crystal with the optical axis lying in the layer plane. The difference between the refractive indices of the ordinary and extraordinary waves for a layer with a porosity of 80% reaches 18%. The experimental data are in agreement with the calculations based on the effective-medium approximation, which takes into account the anisotropy of silicon nanocrystal arrangement in a porous layer.

e15066Background: Aberrant methylation of CpG sites within promoter regions of cancer-related genes is an important epigenetic event in carcinogenesis. The frequency of methylation changes of diffe...

Strong polarization-sensitive anisotropy of the optical absorption in the visible and infrared spectral range is observed in porous silicon (PSi) layers formed from bulk (110) Si wafers. It is shown that the anisotropy of the absorption via band-to-band and intraband (Drude-like) electronic transitions is consistent with the strong birefringence of these layers. Both phenomena are described by a model considering the form anisotropy in the (110) PSi layer assembled from nonspherical Si nanocrystals. We show that the anisotropic shape of the nanocrystals results in polarization-sensitive absorption by their surface silicon-hydrogen bonds. This allows an exact assignment of the stretching modes of silicon monohydride in the infrared absorption spectra of the PSi layers.

Electrochemically nanostructured Si films with surface orientation (110) prepared at different current density were investigated by Fourier transform infrared spectroscopy. The spectra exhibit beats of interference fringes arisen from the summation of intensities of ordinary and extraordinary waves which interfere in the film. The investigated films are shown to exhibit properties of a negative uniaxial crystal (no > ne) with optical axis lying in the surface plane along [001] direction. The value of birefringence reaches 18% for nanostructured Si films with porosity of 80%. Experimental data agree with calculations based on the effective media approximation for anisotropically spaced Si nanocrystals.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Porous-silicon (PS) based multilayer periodic structures with photonic bandgaps (PBGs) and PS single layers that have a strong in-plane birefringence are produced by the electrochemical nanostructuring of crystalline silicon wafers of different crystallographic orientations. Calculations and experiments demonstrate the possibility of improving phase matching for second optical harmonic generation in PS-based PBG structures. Multilayer structures made of birefringent PS exhibit polarization-tunable (dichroic) PBGs, which offer much promise for various optical applications. Improved phase matching was experimentally demonstrated for second-harmonic generation in birefringent PS, suggesting that PBG and birefringent PS structures may serve to phase-match and enhance wave-mixing processes in nonlinear optical materials embedded in the pores of these matrices.