Registration of CBS Effects from Wedge-shaped Samples Containing Particles of Alumina

The paper looks at recent results of research dealing with a coherent backscattering (CBS) on the particles of alumina. It was developed a system of registration of CBS with a tunable dynamic sample. During the experiment the transport mean free path over the width of the peak of angular profile of signal intensity of CBS was determined. Moreover, new scientific data about the CBS’s profiles from randomly inhomogeneous environments were obtained

Free Bicommutative Algebras

2000 Mathematics Subject Classification: Primary 17A50, Secondary 16R10, 17A30, 17D25, 17C50.Algebras with identities a(bc)=b(ac), (ab)c=(ac)b is called bicommutative. Bases and the cocharacter sequence for free bicommutative algebras are found. It is shown that the exponent of the variety of bicommutaive algebras is equal to 2

Interband electron Raman scattering in a quantum wire in a transverse magnetic field

Electron Raman scattering (ERS) is investigated in a parabolic semiconductor quantum wire in a transverse magnetic field neglecting by phonon-assisted transitions. The ERS cross-section is calculated as a function of a frequency shift and magnetic field. The process involves an interband electronic transition and an intraband transition between quantized subbands. We analyze the differential cross-section for different scattering configurations. We study selection rules for the processes. Some singularities in the Raman spectra are found and interpreted. The scattering spectrum shows density-of-states peaks and interband matrix elements maximums and a strong resonance when scattered frequency equals to the "hybrid" frequency or confinement frequency depending on the light polarization. Numerical results are presented for a GaAs/AlGaAs quantum wire.Comment: 8 pages, 5 figure

Risk of acquired drug resistance during short-course directly observed treatment of tuberculosis in an area with high levels of drug resistance.

BACKGROUND: Data on the performance of standardized short-course directly observed treatment (DOTS) of tuberculosis (TB) in areas with high levels of drug resistance and on the potential impact of DOTS on amplification of resistance are limited. Therefore, we analyzed treatment results from a cross-sectional sample of patients with TB enrolled in a DOTS program in an area with high levels of drug resistance in Uzbekistan and Turkmenistan in Central Asia. METHODS: Sputum samples for testing for susceptibility to 5 first-line drugs and for molecular typing were obtained from patients starting treatment in 8 districts. Patients with sputum smear results positive for TB at the end of the intensive phase of treatment and/or at 2 months into the continuation phase were tested again. RESULTS. Among 382 patients with diagnoses of TB, 62 did not respond well to treatment and were found to be infected with an identical Mycobacterium tuberculosis strain when tested again; 19 of these patients had strains that developed new or additional drug resistance. Amplification occurred in only 1.2% of patients with initially susceptible or monoresistant TB strains, but it occurred in 17% of those with polyresistant strains (but not multidrug-resistant strains, defined as strains with resistance to at least isoniazid and rifampicin) and in 7% of those with multidrug-resistant strains at diagnosis. Overall, 3.5% of the patients not initially infected with multidrug-resistant TB strains developed such strains during treatment. Amplification of resistance, however, was found only in polyresistant Beijing genotype strains. CONCLUSIONS: High levels of amplification of drug resistance demonstrated under well-established DOTS program conditions reinforce the need for implementation of DOTS-Plus for multidrug-resistant TB in areas with high levels of drug resistance. The strong association of Beijing genotype and amplification in situations of preexisting resistance is striking and may underlie the strong association between this genotype and drug resistance

Применение экстракорпоральных систем протезирования функций печени при острой декомпенсированной печеночной недостаточности

The aim of the study: to evaluate the efficacy of extracorporeal liver support systems in patients with acute liver failure of various etiologies.Material and methods. The study included 117 patients with acute liver failure of various etiologies. The main group consisted of 71 patients who received complex intensive therapy, including MARS-therapy and hemodiafiltration. The comparison group included 46 patients who received albumin dialysis (24 patients) and hemodiafiltration (22 patients) alone. The mean age of the patients was 34±5.6 years, the majority (56.4%) were men. Dynamic assessment of patients' severity was performed using Sequential Organ Failure Assessment (SOFA) and Model for End-Stage Liver Disease (MELD) scales.Results. A more significant reduction of SOFA and MELD scores was noted as early as by day 10 of intensive therapy in the main group with sequential use of extracorporeal liver detoxification methods — to 2.7±0.2 vs. 8.3±0.5 points (P=0.021) on SOFA and to 16.7±0.4 vs. 23.4±1.4 points (P=0.023) MELD scales. The use of a comprehensive approach to extracorporeal detoxification in acute decompensated liver failure increased the regression rate of multiple organ failure from 51.2 to 74.6% and reduced mortality from 47.8 to 25.4% (χ2=6.266; df=1; P=0.013). At the same time, the cumulative proportion of survivors depending on the type of complication within 30 days was 88.4% in the main group and 69.0% in the comparison group (χ2=4.164; df=1; P=0.042).Conclusion. A comprehensive approach to extracorporeal detoxification is highly effective, providing a more significant reduction of SOFA and MELD scores, increasing the proportion of regression of multiple organ dysfunction and reducing mortality.Цель исследования: выявить эффективность систем экстракорпоральной поддержки печени у пациентов с острой печеночной недостаточностью различного генеза.Материал и методы. В исследование включили 117 пациентов с острой печеночной недостаточностью различного генеза. Основную группу составили 71 пациент, которые получали комплексную интенсивную терапию, включая применение MARS-терапии и гемодиафильтрацию. В группу сравнения включили 46 пациентов, которым применены изолированно альбуминовый диализ — 24 пациента и гемодиафильтрация — 22 пациента. Средний возраст пациентов составил 34±5,6 лет, большинство (56,4%) были мужчины. Динамическую оценку тяжести состояния пациентов проводили по оценочным шкалам Sequential Organ Failure Assessment (SOFA) и Model for End-Stage Liver Disease (MELD).Результаты. Более существенное снижение показателей по шкалам SOFA и MELD отмечено уже к 10 суткам интенсивной терапии в основной группе при последовательном использовании методов экстракорпоральной детоксикации печени по шкале SOFA — до 2,7±0,2 против 8,3±0,5 баллов (p=0,021) и MELD — до 16,7±0,4 против 23,4±1,4 баллов (p=0,023). Применение комплексного подхода к экстракорпоральной детоксикации при острой декомпенсированной печеночной недостаточности позволило увеличить долю регресса полиорганной недостаточности с 51,2 до 74,6%, сократить летальность с 47,8 до 25,4% (χ2=6,266; df=1; p=0,013). При этом кумулятивная доля выживших в зависимости от типа осложнения в сроки до 30 суток составила при 88,4% — в основной группе и 69,0% — в группе сравнения (χ2=4,164; df=1; p=0,042).Заключение. Комплексный подход к экстракорпоральной детоксикации имеет высокую эффективность, обеспечивая более существенное снижение баллов по шкалам SOFA и MELD, позволяет увеличить долю регресса полиорганной дисфункции и сократить летальность

Preparation and analysis of Pr-Ga-Al alloys

Pr-Ga-Al alloys were prepared from individual metals Pr, Ga, Al purified from oxide films in an inert atmosphere of the glove box. The metals were mixed in a certain proportion in crucibles and annealed at 832.4±1.7 °C and 366.2±6.3 °C for 19 hours and 53 hours re-spectively. Three ingots were obtained with different praseodymium content. X-ray phase analysis showed that the dominant phase of these alloys is PrGa6. A formation of Pr(GaAl)2 solid solution was also detected

The microbial load and the severity of morphological changes in the prostate during infection with various titers of uropathogens: a comparison of data from an animal model study

Introduction. It has been established in an animal model that coagulase-negative staphylococci (Staphylococcus haemolyticus) and anaerobes (Peptococcus niger) cause the development of an acute inflammatory process in the prostate when inoculated with 103 CFU/ml. At the same time, data have been published indicating the pathogenic potential of these microorganisms on a titer of 102 CFU/ml. But it was confirmed for the model of acute obstructive pyelonephritis. In addition, the characteristics of the formation of the inflammatory response at different times were determined, which require detailed verification and comparative characteristics with those during infection with a causative uropathogen (Escherichia coli).Objective. Based on the results of the experiment, to carry out: 1) an evaluation of the relationship between the dynamics of microbial load and the degree of pathomorphological changes in prostate tissues during infection with various uropathogens in a titer of 103 CFU/ml; 2) an evaluation of the degree of microbial load and severity of histological changes in prostate tissues on follow-up day 7 with transurethral infection with various uropathogens in a subpathogenic titer of 102 CFU/ml; 3) a fundamental comparative analysis of the indicators of contamination and the severity of inflammatory changes on follow-up day 7 after the inoculation of various uropathogens in titers of 102 and 103 CFU/ml.Materials and methods. The animal model was performed using the FELASA and ARRIVE guidelines. Lab animals: 20 New Zealand rabbits. Uropathogens: E. coli, S. haemolyticus, and P. niger. Infectious titers: 102.3 cfu/ml. Uropathogen inoculation technique: topical transurethral. Randomization: all laboratory animals were divided into 4 groups depending on the uropathogen (3 experimental, 1 control). Follow-up periods: day 1, 3, 7 and 14 for a titer of 103 CFU/ml, and day 7 for a titer of 102 CFU/ml. At the end of the follow-up, euthanasia and autopsy were performed with the extraction of the urogenital organ complex. Hereafter, biopsies were taken from various parts of the prostate. Cultural and histological studies of prostate tissues were carried out using standard methods. The results were analyzed using Statistica 10.2 (StatSoft Inc., Tulsa, OK, USA) and GraphPad Prism 9 (GraphPad Software Inc., Graphpad Holdings LLC, San Diego, CA, USA) programs through descriptive and nonparametric statistics.Results. Bacterial contamination of prostate tissue was determined in all cases of infection with differences (p < 0.05) in some indicators between the E. coli and P. niger groups at different observation periods, but only in the case of inoculation of the test titer of 103 CFU/ml. Histological evaluation of prostate tissues after inoculation with 103 CFU/ml verified the presence of acute destructive changes in the prostate from the follow-up day 1, which were more pronounced in the S. haemolyticus and E. coli groups. However, similar characteristics of the development of the inflammatory process in the form of hyper-eosinophilic infiltration in the early stages and pronounced congestion of the prostatic glands were identified in the S. haemolyticus and P. niger groups. Comparison of trends in dynamic changes of microbial load (rise / decline) and severity of pathological changes (increase / resolution) in prostate tissues in established follow-up periods showed the presence of relative synchronization of trends (from days 1 to 7) in the S. haemolyticus and P. niger groups, and complete synchronization in the E. coli group. When comparing the median microbial load of the prostate on the follow-up day 7, no intergroup (p > 0.05) differences were found both in cases of infection with a titer of 103 CFU/ml, and when compared with the data on contamination for a test titer of 102 CFU/ml, at the same time observations. At once, when E. coli and S. haemolyticus were infected at a subpathogenic titer of 102 CFU/ml, inflammatory changes were recorded that had a mild diffuse character, in relation to those after inoculation of these pathogens in a titer of 103 CFU/ml. In turn, P. niger induced the development of low-intensity focal alteration in isolated areas of prostate tissues.Conclusions. Detailed analysis of culture and histological data showed that E. coli, S. haemolyticus and P. niger have significant pathogenic potential at titer of 103 CFU/ml. In turn, when the titer decreases to 102 CFU/ml, E. coli and S. haemolyticus retain their pathogenic potential, but the severity of the inflammatory reaction is significantly reduced. It was also found that a change in bacterial contamination affects the severity of the inflammatory process in all groups during seven follow-up days at a given test titer