A method for calculating the productivity of cable communications networks

A probabilistic-mathematical instrument was used to develop a method fo

Optical echo in photonic crystals

The dynamics of photonic wavepacket in the effective oscillator potential is studied. The oscillator potential is constructed on a base of one dimensional photonic crystal with a period of unit cell adiabatically varied in space. The structure has a locally equidistant discrete spectrum. This leads to an echo effect, i.e. the periodical reconstruction of the packet shape. The effect can be observed in a nonlinear response of the system. Numerical estimations for porous-silicon based structures are presented for femtosecond Ti:Sapphire laser pump.Comment: 4 page

Sex, Age, and Socioeconomic Differences in Nonfatal Stroke Incidence and Subsequent Major Adverse Outcomes

BACKGROUND AND PURPOSE: Data about variations in stroke incidence and subsequent major adverse outcomes are essential to inform secondary prevention and prioritizing resources to those at the greatest risk of major adverse end points. We aimed to describe the age, sex, and socioeconomic differences in the rates of first nonfatal stroke and subsequent major adverse outcomes. METHODS: The cohort study used linked Clinical Practice Research Datalink and Hospital Episode Statistics data from the United Kingdom. The incidence rate (IR) ratio of first nonfatal stroke and subsequent major adverse outcomes (composite major adverse cardiovascular events, recurrent stroke, cardiovascular disease-related, and all-cause mortality) were calculated and presented by year, sex, age group, and socioeconomic status based on an individual's location of residence, in adults with incident nonfatal stroke diagnosis between 1998 and 2017. RESULTS: A total of 82 774 first nonfatal stroke events were recorded in either primary care or hospital data-an IR of 109.20 per 100 000 person-years (95% CI, 108.46-109.95). Incidence was significantly higher in women compared with men (IR ratio, 1.13 [95% CI, 1.12-1.15]; P<0.001). Rates adjusted for age and sex were higher in the lowest compared with the highest socioeconomic status group (IR ratio, 1.10 [95% CI, 1.08-1.13]; P<0.001). For subsequent major adverse outcomes, the overall incidence for major adverse cardiovascular event was 38.05 per 100 person-years (95% CI, 37.71-38.39) with a slightly higher incidence in women compared with men (38.42 versus 37.62; IR ratio, 1.02 [95% CI, 1.00-1.04]; P=0.0229). Age and socioeconomic status largely accounted for the observed higher incidence of adverse outcomes in women. CONCLUSIONS: In the United Kingdom, incidence of initial stroke and subsequent major adverse outcomes are higher in women, older populations, and people living in socially deprived areas

Nonlinear acoustic waves in channels with variable cross sections

The point symmetry group is studied for the generalized Webster-type equation describing non-linear acoustic waves in lossy channels with variable cross sections. It is shown that, for certain types of cross section profiles, the admitted symmetry group is extended and the invariant solutions corresponding to these profiles are obtained. Approximate analytic solutions to the generalized Webster equation are derived for channels with smoothly varying cross sections and arbitrary initial conditions.Comment: Revtex4, 10 pages, 2 figure. This is an enlarged contribution to Acoustical Physics, 2012, v.58, No.3, p.269-276 with modest stylistic corrections introduced mainly in the Introduction and References. Several typos were also correcte

The impact of self-isolation on the socio-psychological state of a person: research results

Based on the analysis of the results of the survey conducted by the authors through a service such as Google Forms, some aspects of the impact of the COVID-19 coronavirus pandemic on the socio-psychological state of a person are considered. The sample of respondents can be described as spontaneous. The age of respondents in the range from 14 to 71 years, these are residents of different states, localities, differing in the nature of leading activities and social status. However, the results of the study demonstrate that place, age, status and other characteristics are not crucial in terms of socio-psychological well-being during the pandemic. Among the main problems faced by the population in the conditions of the pandemic are limited contacts and movement, difficulties with the organization of school-age children’s studies, loss of work and reduced income, fear for their health and the health of loved ones

Lattice Boltzmann simulations in microfluidics: probing the no-slip boundary condition in hydrophobic, rough, and surface nanobubble laden microchannels

In this contribution we review recent efforts on investigations of the effect of (apparent) boundary slip by utilizing lattice Boltzmann simulations. We demonstrate the applicability of the method to treat fundamental questions in microfluidics by investigating fluid flow in hydrophobic and rough microchannels as well as over surfaces covered by nano- or microscale gas bubbles.Comment: 11 pages, 6 figure

Initial stage of formation of spontaneous invasive populations of garden lupine (lupinus polyphyllus lindl.) at the northern limit of its secondary distribution range in the veps forest nature park

A weed plant of the species Lupinus polyphyllus was found in settlements located on the territory of the natural park «Vepssky forest» of the Leningrad regio

Клинико-лабораторная характеристика микобактериоза у лиц, живущих с ВИЧ, и клинический случай тяжелого течения генерализованного микобактериоза

Relevance. In the context of HIV epidemic, the number of cases of mycobacteriosis has increased.The objective was to study clinical and laboratory characteristics of mycobacteriosis in HIV patients; to present a clinical case of severe generalized mycobacteriosis.Methods and materials. Retrospective analysis of 48 cases from the archives of the St. Petersburg State Budgetary Healthcare Institution «S. P. Botkin Clinical Infectious Diseases Hospital» over the period from 2016 to 2018 was performed. The inclusion criterion was newly diagnosed mycobacteriosis. The following parameters were evaluated: HIV infection duration and stage; antiretroviral therapy (ART) duration; the primary syndrome and form of mycobacteriosis; laboratory and instrumental findings; causative pathogen verification methods.Results. Median number of CD4-lymphocytes (CD4 + ) was 6.9 cell/pl. In 33.3 % of patients, HIV infection was diagnosed within 1 year before the detection of mycobacteriosis. The primary syndromes were: febrile-toxic syndrome (72.9 %), bronchopulmonary syndrome (29.2 %), diarrhea syndrome (18.8 %), abdominal pain syndrome (10.4 %). Generalized myco-bacteriosis was diagnosed in 65.3 % patients. Anemia was registered in in 96 % patients, leukopenia — in 43.8 % patients. Lymphadenopathy of various localization was the most common instrumental finding (75 %). The diagnosis was confirmed bacteriologically in 70.8 % cases. Mycobacterium avium complex group was predominant (62.5 %). There were 18.8 % deaths.Conclusion. Mycobacteriosis developed in patients with advanced immunodeficiency. Clinical and laboratory findings were nonspecific. There was a trend towards generalization of infection. The proportion of deaths indicates the high importance of mycobacteriosis in the structure of mortality in HIV patients. Введение. В условиях эпидемии ВИЧ-инфекции растет число случаев микобактериоза.Цель — оценить клинико-лабораторные данные микобактериоза у пациентов с ВИЧ-инфекцией; представить клинический случай тяжелого течения генерализованного микобактериоза.Методы и материалы. Ретроспективный анализ 48 случаев по материалам из архива СПбГБУЗ «Клиническая инфекционная больница им. С. П. Боткина» за 2016 — 2018 гг. Критерий включения — впервые установленный диагноз микобактериоза. Оценивали длительность и стадию ВИЧ-инфекции; длительность антиретровирусной терапии; ведущий симптомокомплекс и форму микобактериоза; данные лабораторных, инструментальных исследований; методы верификации возбудителя.Результаты. Медиана числа CD4-лимфоцитов: 6,9 кл/мкл. У 33,3 % пациентов ВИЧ-инфекция диагностирована в течение 1 года до выявления микобактериоза. Ведущие синдромы: лихорадочно-интоксикационный (72,9 %), бронхопульмональный (29,2 %), диарейный (18,8 %), синдром абдоминальных болей (10,4 %). У 65,3 % пациентов диагностирован генерализованный микобактериоз. У 96 % пациентов наблюдалась анемия, у 43,8 % — лейкопения. Наиболее частыми инструментальными данными был синдром лимфаденопатии различной локализации (75 %). Диагноз подтвержден бактериологически в 70,8 % случаев. Преобладали бактерии группы Mycobacterium avium complex (62,5 %). Летальные исходы были в 18,8 % случаев.Заключение. Микобактериоз развивался у лиц с глубоким иммунодефицитом. Клиническая и лабораторная картина неспецифична. Отмечалась склонность к генерализации инфекции. Доля летальных исходов указывает на высокую значимость микобактериоза в структуре летальности пациентов с ВИЧ-инфекцией.

Efficacy and safety of the use of rebamipide in the scheme of triple eradication therapy of Helicobacter pylori infection: a prospective randomized comparative study

Purpose of the study. To evaluate the effectiveness and safety of the use of rebamipide as part of the triple eradication therapy (ET) scheme of Helicobacter pylori infection. Materials and methods. A prospective, randomized comparative study included 94 patients with uncomplicated H. pylori-associated stomach / duodenal ulcer. In the process of randomization, patients are divided into three groups depending on the intended therapy. The first group (n=36) received a classical triple scheme of the first-line ET (omeprazole 20 mg twice a day, amoxicillin 1000 mg twice a day, clarithromycin 500 mg twice a day) for 10 days. Patients of the second group (n=33) were assigned a classical triple scheme of ET with the inclusion of rebamipide (omeprazole 20 mg twice a day, amoxicillin 1000 mg twice a day, clarithromycin 500 mg twice a day, rebamipide 100 mg 3 times a day day) for 10 days. Patients of the third group (n=25) were assigned a classical triple scheme of ET with the inclusion of rebamipide (omeprazole 20 mg twice a day, amoxicillin 1000 mg twice a day, clarithromycin 500 mg twice a day, rebamipide 100 mg 3 times a day) in for 10 days, with the prolongation of the administration of rebamipide for the next 20 days. The effectiveness of ET was determined by the respiratory test after 6 weeks after the end of treatment. Adverse events were recorded by patients in specially developed diaries. All patients with gastric ulcer at the 6th week underwent a histological examination of the biopsy specimens of the antrum and the body of the stomach, assessing the inflammatory activity of the process on a point system in accordance with the updated Sydney system. Results and discussion. Efficiency of H. pylori eradication in the first group was 77.7% (ITT), 82.3% (PP), in the second group - 81.8% (ITT), 84.4% (PP), and in the third group - 84% (ITT), 87.5% (PP). The use of rebamipide in the triple ET regimen was associated with an increase in H. pylori eradication efficiency, both with simultaneous use with the scheme [odds ratio (OR) 1.16; 95% confidence interval (CI) 0.32-4.24], and with subsequent prolonged admission (OR 1.5, 95% CI 0.34-6.7). A somewhat more pronounced dynamics of the epithelization of erosive and ulcerative changes in the mucous membrane of the stomach and duodenum to the 21st and 28th days in the third group of patients was noted. The incidence of adverse events between the groups was comparable: 22.2% in the first group, 24.2% in the second group and 20% in the third group. In the pathomorphological evaluation of biopsy specimens of patients with gastric ulcer at the 6th week after the treatment, significant differences were revealed between the first and third groups in terms of the inflammatory activity in the antrum stomach (2±0.63 vs. 1.4±0.52; p=0,0399). The conclusion. The inclusion of rebamipide in the classical triple scheme of H. pylori ET increases the effectiveness of treatment and does not affect the safety profile. In the post-eradication period, it is advisable to continue the use of rebamipide to potentiate the repair of the gastric mucosa and regress the inflammatory processes

Evaluation of the efficacy and safety of the hybrid scheme for eradication therapy of Helicobacter pylori infection

The aim is to conduct a comprehensive comparative study of the efficacy and safety of the hybrid scheme of eradication therapy (ET) in patients with peptic ulcer of the stomach or duodenum associated with Helicobacter pylori. Materials and methods. In a prospective, randomized comparative study, 180 patients were divided into three equal groups of 60 people, depending on the prescribed 10-day ET regimen. Group 1 - the standard triple scheme (omeprazole, amoxicillin and clarithromycin); group 2 - four-component therapy with preparations of bismuth (omeprazole, tetracycline, metronidazole, bismuth tricalium dicitrate); group 3 - hybrid scheme (first 5 days: omeprazole and amoxicillin, the next 5 days: omeprazole, amoxicillin, clarithromycin, metronidazole). The effectiveness of ET was determined with the help of a breath test a month after the end of therapy. Adverse events were recorded by patients in specially developed diaries. Pharmacoeconomic analysis was carried out using the "cost-effectiveness" method with calculation of the CER coefficient. Results and discussion. The effectiveness of standard triple therapy was 73.3% (ITT), 75.9% (PP); four-component therapy with bismuth preparations - 78.3% (ITT), 82.4% (PP); hybrid scheme - 85% (ITT), 91% (PP). Hybrid therapy proved to be significantly more effective than standard triple therapy with a odds ratio (OR) of 3.25; 95% confidence interval (CI) 1.08-9.73 (p=0.043, χ2=4.75, p-level=0.029298). The incidence of adverse events with the use of triple, four-component and hybrid ET regimens was 15; 18.3 and 28.3% respectively. The OR of at least one adverse event in patients receiving a hybrid ET regimen compared with triple therapy was 2.24 (95% CI 0.91-5.53, p=0.0823, χ2=3.14, p-level=0.076394), and compared with the four-component therapy - 1.76 (95% CI 0.74-4.17, p=0.2804, χ2=1.68, p-level=0.194924). According to the results of the pharmacoeconomic analysis, the most profitable from an economic point of view was a hybrid ET scheme with a CER of 20.1. The conclusion. Hybrid therapy showed the greatest effectiveness in comparison with the triple and four-component ET regimens, however, the incidence of side effects in patients receiving the hybrid ET scheme was higher, although it remained within the acceptable level for use in clinical practice. Pharmacoeconomic analysis also showed the advisability of designating a hybrid ET scheme. The obtained data allow to draw a conclusion about the necessity of further study of the efficiency and safety of the hybrid ET scheme