Major Challenges in clinical management of TB/HIV coinfected patients in Eastern Europe compared with Western Europe and Latin America

Objectives: rates of TB/HIV coinfection and multi-drug resistant (MDR)-TB are increasing in Eastern Europe (EE). We aimed to study clinical characteristics, factors associated with MDR-TB and predicted activity of empiric anti-TB treatment at time of TB diagnosis among TB/HIV coinfected patients in EE, Western Europe (WE) and Latin America (LA). Design and methods: between January 1, 2011, and December 31, 2013, 1413 TB/HIV patients (62 clinics in 19 countries in EE, WE, Southern Europe (SE), and LA) were enrolled. Results: significant differences were observed between EE (N = 844), WE (N = 152), SE (N = 164), and LA (N = 253) in the proportion of patients with a definite TB diagnosis (47%, 71%, 72% and 40%, p<0.0001), MDR-TB (40%, 5%, 3% and 15%, p<0.0001), and use of combination antiretroviral therapy (cART) (17%, 40%, 44% and 35%, p<0.0001). Injecting drug use (adjusted OR (aOR) = 2.03 (95% CI 1.00-4.09), prior anti-TB treatment (3.42 (1.88-6.22)), and living in EE (7.19 (3.28-15.78)) were associated with MDR-TB. Among 585 patients with drug susceptibility test (DST) results, the empiric (i.e. without knowledge of the DST results) anti-TB treatment included ≥3 active drugs in 66% of participants in EE compared with 90-96% in other regions (p<0.0001). Conclusions: in EE, TB/HIV patients were less likely to receive a definite TB diagnosis, more likely to house MDR-TB and commonly received empiric anti-TB treatment with reduced activity. Improved management of TB/HIV patients in EE requires better access to TB diagnostics including DSTs, empiric anti-TB therapy directed at both susceptible and MDR-TB, and more widespread use of cART

On the interplay between Babai and Černý’s conjectures

Motivated by the Babai conjecture and the Černý conjecture, we study the reset thresholds of automata with the transition monoid equal to the full monoid of transformations of the state set. For automata with n states in this class, we prove that the reset thresholds are upperbounded by 2n2 -6n + 5 and can attain the value (Formula presented). In addition, we study diameters of the pair digraphs of permutation automata and construct n-state permutation automata with diameter (formula presented). © Springer International Publishing AG 2017

Influence of fiber type and matrix composition on adhesive strength in fiber reinforced concrete

Introduction. The purpose of the article is to determine the influence of the steel fiber profile and the composition of the matrix on their adhesion in dispersed reinforced concrete.Materials and methods. Studies have been carried out using the test methods set out in national standards. To determine the characteristics of the adhesion strength of fibers with a matrix, an original technique developed at SPbGASU was used.Results. The degree of influence of the geometric shape of steel fibers – anchor and wave profile on the adhesion strength characteristic is determined. The adhesion strength of steel fiber with cement and concrete matrix was assessed (Cement: Sand = 1:1, Cement: Sand = 1:2 and Cement: Sand = 1:3). The influence of the volume fraction of the cement paste on the characteristic of the adhesion strength of the steel fiber with the matrix has been experimentally proven.Conclusions. The experimental data obtained confirm the effectiveness of dispersed reinforcement through the use of anchor fibers in combination with a rationally selected composition of the concrete matrix

Evaluation of dispersion reinforcement in concrete in terms of strength and crack resistance

Introduction. The purpose of the study was to evaluate the effectiveness of dispersed concrete reinforcement in terms of strength and crack resistance.Materials and methods. When conducting research, test methods were used, regulated by the provisions of national standards, equipment specially designed for this study was used.Results. The results of testing fiber-reinforced concretes made using low-modulus and high-modulus fibers are presented.Discussion and conclusions. As a result of the analysis of the data presented, it is shown that in order to assess the effectiveness and the correct choice of reinforcing fibers, it is not enough to characterise fiber-reinforced concrete only by tensile strength in bending. For a more accurate assessment, it is proposed to use crack resistance characteristics, for example, the critical stress intensity factor, or to supplement the description of the advantages of dispersed reinforcement with the features of the behavior of fiber-reinforced concrete under load

Incidence of cancer and overall risk of mortality in individuals treated with raltegravir-based and non-raltegravir-based combination antiretroviral therapy regimens

Objectives: There are currently few data on the long-term risk of cancer and death in individuals taking raltegravir (RAL). The aim of this analysis was to evaluate whether there is evidence for an association. Methods: The EuroSIDA cohort was divided into three groups: those starting RAL-based combination antiretroviral therapy (cART) on or after 21 December 2007 (RAL); a historical cohort (HIST) of individuals adding a new antiretroviral (ARV) drug (not RAL) to their cART between 1 January 2005 and 20 December 2007, and a concurrent cohort (CONC) of individuals adding a new ARV drug (not RAL) to their cART on or after 21 December 2007. Baseline characteristics were compared using logistic regression. The incidences of newly diagnosed malignancies and death were compared using Poisson regression. Results: The RAL cohort included 1470 individuals [with 4058 person-years of follow-up (PYFU)] compared with 3787 (4472 PYFU) and 4467 (10 691 PYFU) in the HIST and CONC cohorts, respectively. The prevalence of non-AIDS-related malignancies prior to baseline tended to be higher in the RAL cohort vs. the HIST cohort [adjusted odds ratio (aOR) 1.31; 95% confidence interval (CI) 0.95–1.80] and vs. the CONC cohort (aOR 1.89; 95% CI 1.37–2.61). In intention-to-treat (ITT) analysis (events: RAL, 50; HIST, 45; CONC, 127), the incidence of all new malignancies was 1.11 (95% CI 0.84–1.46) per 100 PYFU in the RAL cohort vs. 1.20 (95% CI 0.90–1.61) and 0.83 (95% CI 0.70–0.99) in the HIST and CONC cohorts, respectively. After adjustment, there was no evidence for a difference in the risk of malignancies [adjusted rate ratio (RR) 0.73; 95% CI 0.47–1.14 for RALvs. HIST; RR 0.95; 95% CI 0.65–1.39 for RALvs. CONC] or mortality (adjusted RR 0.87; 95% CI 0.53–1.43 for RALvs. HIST; RR 1.14; 95% CI 0.76–1.72 for RALvs. CONC). Conclusions: We found no evidence for an oncogenic risk or poorer survival associated with using RAL compared with control groups.Peer reviewe

ПРИМЕНЕНИЕ ИТЕРАЦИОННОГО ДИНАМИЧЕСКОГО ПРОГРАММИРОВАНИЯ В ЗАДАЧАХ СИНТЕЗА ОПТИМАЛЬНОГО УПРАВЛЕНИЯ С ПОЛНОЙ ОБРАТНОЙ СВЯЗЬЮ

This paper presents a generalization of iterative dynamic programming using Luus-Jakola optimization procedure applied to the solution of optimal feed-back control for nonlinear deterministic systems. Iterative dynamic programming is realized. Efficiency of proposed method is tested on the software complex developed by the authors in C++; a model example of chemical process control is presented.В работе предложено обобщение процедуры итерационного динамического программирования с применением последовательной редукции множества допустимых решений (метода Luus-Jakola) на задачи оптимального управления нелинейными непрерывными детерминированными системами с полной обратной связью. Оно включает поиск коэффициентов представления закона управления функцией насыщения, учитывающей ограничения на величину управления, содержащей в качестве аргумента сумму произведений ортонормированных функций, образующих базисную систему. На основе предложенного алгоритма разработан комплекс программ, эффективность которого продемонстрирована на модельном примере управления химическим процессом

ПРИМЕНЕНИЕ ГИБРИДНОГО МЕТОДА СЛУЧАЙНОГО ПОИСКА В ЗАДАЧАХ ОПТИМИЗАЦИИ ЭЛЕМЕНТОВ ТЕХНИЧЕСКИХ СИСТЕМ

This paper presents a modification of the Luus-Jaakola global optimization method, which belongs to the class of metaheuristic algorithms. A hybrid method is suggested, using a combination of random search methods: Luus-Jaakola method, adaptive random search method and best trial method. The obtained method is applied to the optimization of parameters of different engineering systems. This class of problems appears during the design of aerospace and aeronautical structures; its goal is the cost or weight minimization of the construction. These problems belong to the class of constrained global optimization problems, where the level surface of the objective function has uneven relief and there is a large number of variables. This means that the classical optimization methods prove to be inefficient and these problems should be solved using metaheuristic optimization methods, which provide sufficient accuracy at reasonable operating time. In this paper, the constrained global optimization problem is solved using the penalty method. Thus, the problem of exterior penalty function optimization is considered, where the penalty coefficients are chosen in such a way as to avoid the violation of the constraints. Two applied problems are considered in the paper: the determination of the high-pressure vessel parameters and the anti rattle spring parameters determination. Using the suggested algorithm, a software complex was developed, which allows us to solve engineering optimization problems. The results obtained using the suggested methods were compared with the results obtained using the non-modified Luus-Jaakola method in order to demonstrate the efficiency of the suggested hybrid random search method.В работе предложена модификация метода случайного поиска с последовательной редукцией области исследования (метода Luus – Jaakola), относящегося к классу метаэвристических методов поиска глобального экстремума. Предложен гибридный метод глобальной оптимизации, основанный на совместном использовании метода случайного поиска с последовательной редукцией области исследования, метода адаптивного случайного поиска и метода поиска наилучшей пробы. Полученный модифицированный метод применен для решения прикладных инженерных задач оптимизации параметров технических систем. Этот класс задач возникает при проектировании ракетно-космических и авиационных конструкций. Целью таких задач является минимизация стоимости или веса рассматриваемой конструкции. Подобные задачи представляют собой задачи условной глобальной оптимизации со сложным рельефом поверхностей уровня целевой функции и с большим числом переменных, что делает применение классических методов глобальной оптимизации малоэффективным, в то время как использование метаэвристических методов позволяет получить достаточно точное решение за приемлемое время. В работе решение задачи глобальной условной оптимизации происходит с использованием метода внешних штрафов. Выполняется переход к задаче оптимизации вспомогательной целевой функции, при этом параметры штрафа подбираются так, чтобы выполнялись наложенные ограничения, определяющие множество допустимых решений. В работе рассмотрены две прикладные задачи: определение параметров сосуда высокого давления и определение параметров натяжной/компрессионной пружины. На основе предложенного алгоритма разработан комплекс программ, решающих данные прикладные задачи, результаты работы которого сравниваются с результатами работы немодифицированного метода случайного поиска с последовательной редукцией области исследования и другими метаэвристическими алгоритмами. Сравнение полученных результатов демонстрирует эффективность предложенного метода

IMPROVEMENT OF TREATMENT OF UNFORMED DUODENAL AND HIGH JEJUNAL FISTULAS

This article shows many years of surgical experience of treatment of unformed duodenal and high jejunal fistulas using specific combined methods in main treatment group. The review covers the period from 2000 to 2016 years, which includes treatment of 132 patients who suffered from unformed duodenal and high jejunal fistulas. The research was conducted on the basis of the Republic Clinical hospital of G.G. Kuvatov in Bashkortostan. We followed the purpose of analysis and evaluation of the structure and quantity of early postoperative complications, including purulent-septic complications, as well as postoperative lethality, by comparing the main and control groups of treated patients, who received different kinds of therapy of unformed duodenal and jejunal fistulas. The treatment complex (main treatment group) consists of local use of collagen to strengthen intestinal sutures; selective injections of angioprotectors to blood vessels to improve microcirculation and trophic tissues; laser and antibiotic therapy for better eradication of microorganisms. The obtained results showed that the technique developed by us allowed to reduce the frequency of inconsistency of intestinal sutures, the number of newly formed intestinal fistula and purulent-septic complications in the treatment of patients with unformed duodenal and high jejunal fistulas