Modal Phenomena of Surface and Bulk Polaritons in Magnetic- Semiconductor Superlattices

We discuss peculiarities of bulk and surface polaritons propagating in a composite magnetic-semiconductor superlattice influenced by an external static magnetic field. Three particular configurations of magnetization, namely, the Voigt, polar, and Faraday geometries, are considered. In the long-wavelength limit, involving the effective medium theory, the proposed superlattice is described as an anisotropic uniform medium defined by the tensors of effective permittivity and effective permeability. The study is carried out in the frequency band where the characteristic resonant frequencies of underlying constitutive magnetic and semiconductor materials of the superlattice are different but closely spaced. The effects of mode crossing and anti-crossing in dispersion characteristics of both bulk and surface polaritons are revealed and explained with an assistance of the concept of Morse critical points from the catastrophe theory

Justification of stripping and development of a modular mine site for a combined coal mining method in Kuzbass on the example Baikaimskaya mine site

The article considers one actual method for development coal deposits in the Kuzbass by open-underground mining. The scientific and practical advantages of the proposed method due to the use of common infrastructure of coal mine and a modular mine site (subsequently transformed into a mining and technological structure operating according to the mine – longwall scheme) are presented. Currently, a development strategy for Kuzbass until 2035 has been developed. As part of the strategy, a draft program for subsoil use is being formed in the coal industry department. The program should take into account all the positive and negative aspects associated with coal mining in cities and municipal areas and also their prospects. In the Kuznetsk coal basin, 42 mines and 52 opencast mines are mining, of which 12 enterprises use partially unified infrastructure. According to the results of open-underground mining work conducted by the laboratory of the Institute of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences (Institute of Coal SB RAS), the list of sites includes favorable mining and geological conditions with incidence angles of up to 18 degrees. As open-pit coal production increases, many sites encounter such a parameter as maximum allowable (boundary) strip ratio. At the stage of preparing the feasibility study for the development of a coal deposit, this coefficient is calculated first of all, since duration of enterprise’s work and its economic component depend on it. In order to increase parameters, it is necessary to carry out transition from open works to underground. As a result, coal mine will not work at a loss, providing production with an economically disadvantageous strip ratio

Variability in interpretation of chest radiographs among Russian clinicians and implications for screening programmes: observational study.

OBJECTIVE: To determine variability in interpretation of chest radiographs among tuberculosis specialists, radiologists, and respiratory specialists. DESIGN: Observational study. SETTING: Tuberculosis and respiratory disease services, Samara region, Russian Federation. PARTICIPANTS: 101 clinicians involved in the diagnosis and management of pulmonary tuberculosis and respiratory diseases. MAIN OUTCOME MEASURES: Interobserver and intraobserver agreement on the interpretation of 50 digital chest radiographs, using a scale of poor to very good agreement (kappa coefficient: < or = 0.20 poor, 0.21-0.40 fair, 0.41-0.60 moderate, 0.61-0.80 good, and 0.81-1.00 very good). RESULTS: Agreement on the presence or absence of an abnormality was fair only (kappa = 0.380, 95% confidence interval 0.376 to 0.384), moderate for localisation of the abnormality (0.448, 0.444 to 0.452), and fair for a diagnosis of tuberculosis (0.387, 0.382 to 0.391). The highest levels of agreement were among radiologists. Level of experience (years of work in the specialty) influenced agreement on presence of abnormalities and cavities. Levels of intraobserver agreement were fair. CONCLUSIONS: Population screening for tuberculosis in Russia may be less than optimal owing to limited agreement on interpretation of chest radiographs, and may have implications for radiological screening programmes in other countries

SIMULTANEOUS OPERATIONS TACTICS IN PATIENTS WITH VENTRAL HERNIAS

Objectives - to improve treatment results in patients with ventral hernia and the concurrent surgical diseases by means of the designed surgery tactics. Material and methods. The treatment of 834 patients with ventral hernia, aged from 18 up to 82 years, was analyzed. The group consisted of 196 men (23.5%) and 638 women (76.5%). According to the European Hernia Society (EHS) classification of postoperative ventral hernias the gate types were distributed in patients as follows: W1 - in 132 patients (15.8%), W2 - in 397 (47.6%), W3 - in 305 (36.6%), in 243 (29.1%) cases the hernias were recurrent. 394 (47.2%) patients had 597 simultaneous interventions. The treatment tactics for the patients with hernias and associated diseases was defined according to the designed classification. For the abdominal wall repair the 2 variants of the "tension-free" mesh repair technique were used. Results. Forced simultaneous interventions were performed in 34 patients when the intestinal loops adherent to the scar were situated in the hernia sac. In 27 cases the postoperative ventral hernia was combined to the intestinal fistulas, located out of the hernia area. 12 patients underwent herniolaparotomy conditioned by the intra-abdominal intestinal fistulas closure and small hernias size. To prevent the compartment syndrome in 3 patients with splanchnoptosis the right part of the colon was resected. 103 patients had the planned simultaneous operations including the laparoscopic cholecystectomy in 19 cases, 114 patients underwent the panniculectomy. The preventional appendectomy was performed in patients with the recurrent large hernias. In 140 cases the omentum resection was done due to the signs of the chronical strangulation and omentitis. Postoperative pulmonary artery thromboembolia was the death cause for 3 (0.4%) patients. Only 8 (0.9%) patients suffered the partial hernia recurrence. Conclusion. In patients with hernias the simultaneous operations are conditioned by the pathogenesis and do not affect the severity and frequency of wound complications in the postoperative period. A condition for the simultaneous interventions in patients with hernias is the necessary implementation of the combined techniques of the ventral tension-free mesh hernioplasty

Detection of rifampicin and izoniazid resistance in Mycobacterium tuberculosis strains from Samara Region (Central Russia)

Recently high rates of tuberculosis incidence and prevalence are observed in civilian and prisons sectors in Russia. One of the main reasons for high morbidity levels and ineffectiveness of treatment is wide spreading of drug resistant Mycobacterium tuberculosis strains, but accurate and comprehensive information on levels of drug resistance among strains circulating in Central Russia is unavailable. Rifampicin and izoniazid resistance detection in TB isolates from Samara (Central Russia) civilian and prison TB hospitals and dispensaries in 2000–2002 by revealing mutations in rpoB, katG and inhA genes using Macroarray technique. Methods: A total of 342 M. tuberculosis isolates were tested using Macroarray method. It is based on multiplex amplification of rpoB, katG and inhA genes fragments (with three pairs of biotin labeled primers) following by dothybridization with normal and mutant oligonucleotide probes (fragments of rpoB, katG and inhA genes in which mutations occur) immobilized on nylon membrane strips. Mycobacterial DNA was extracted by heating of cell suspensions following by chloroform extraction. Streptavidin-alkaline phosphatase color development system was used for visualization of results

Особенности фармакотерапии специфических и неспецифических инфекций респираторного тракта в лечебных учреждениях Самарской области

Irrational administration of antimicrobials, incorrect regimens and dosing provide occurrence of adverse effects with minimal therapeutic results and development of drug resistance including anti-tuberculosis drugs. The study was designed to detect information sources on drug therapy used by general practitioners and TB specialists, to establish stereotypical models of antibacterial drug administration in prevalent upper and lower airway diseases at the Samara region and to substantiate the supposition about unreasonable empiric administration of anti-tuberculosis drugs in a respiratory patient without microbiological confirmation as a probable cause of drug resistant tuberculosis. A cross-sectional study based on a special questionnaire was performed in 425 general practitioners in primary care facilities, hospitals and in TB specialists at the Samara region. The questionnaire contained several clinical situations and their solving and the respondents should choose the most suitable ones. Results demonstrated that majority of the practitioners (80 %, or 340 / 425 cases) widely use advertising information regarding antimicrobials. Several doctors (1.7 %) chose antibacterial drugs to treat acute respiratory viral infection, 0.8 to 1.6 % of doctors certainly decided to administer anti-tuberculotics in non-TB respiratory diseases such as acute bronchitis, chronic obstructive pulmonary disease, communityacquired pneumonia and acute tonsillitis, and approximately one fifth of the practitioners thought to administer antituberculotics in these diseases (18.4 % (78 / 425) – rifampicin, 21.2 % (90 / 425) – isoniasid).Нерациональное назначение антибактериальных средств и неверно выбранные схемы и дозировки способствуют развитию побочных эффектов (при минимальном терапевтическом эффекте) и возникновению лекарственной устойчивости к препаратам основных групп антибиотиков, в т. ч. и к противотуберкулезным препаратам. В цели исследования входило определить источники информации по схемам лечения, используемым врачами общей лечебной сети и фтизиатрами противотуберкулезной службы, выявить стереотипные модели назначения антибактериальных препаратов, используемых в Самарской области для лечения наиболее распространенных заболеваний верхних и нижних дыхательных путей, и обосновать положение о том, что возможными предпосылками возникновения лекарственной устойчивости к противотуберкулезным препаратам может служить бездоказательное эмпирическое назначение таких препаратов при наличии у больного симптомов респираторного заболевания с неподтвержденной туберкулезной этиологией. Одномоментное исследование, в основе которого лежало применение специально разработанного вопросника, было проведено среди 425 врачей первичного медицинского звена, терапевтов стационаров и фтизиатров противотуберкулезных учреждений Самарской области. Вопросник содержал описание нескольких клинических ситуаций, респонденты должны были выбрать наиболее подходящие для этих ситуаций ответы. Результаты исследования показали, что рекламная информация по назначению антибиотиков, предоставляемая фармацевтическими компаниями, широко – в 80 % (340 / 425) случаев – используется большинством врачей. Небольшая группа врачей (1,7 %) выбрала назначение антибиотиков для лечения острого респираторного заболевания; от 0,8 % до 1,6 % врачей указали, что непременно назначат противотуберкулезные препараты для лечения четырех заболеваний дыхательных путей нетуберкулезной этиологии (острого бронхита, хронической обструктивной болезни легких, внебольничной пневмонии и острого тонзиллита), примерно пятая часть врачей не исключает назначения противотуберкулезных препаратов (18,4 %, (78 / 425) – Рифампицин; 21,2 % (90 / 425) – Изониазид) при лечении перечисленных заболеваний