Evidence for photochemical transformations in porous silicon

The dynamics of the variation of photoluminescence intensity (PLI) of porous silicon (PS) samples subjected to laser irradiation (337 nm, 3.7 mW) during their ageing in air has been studied. The PLI turned out to increase rapidly under UV irradiation and to flatten out in several hours. The subsequent irradiation leads to intensity degradation, which may be explained by the luminescence fatigue effect. At the same time, the PLI of the unilluminated sample almost does not change during the experiment. It turned out that the anomaly as a small surge down is observed on the PLI evolution curve at the stage of the initial monotonous increase of PLI after a short-time (1 to 2 minutes) interruption of the laser illumination of the sample, whereas this anomaly is a surge up at the stage of the monotonous fall of the PLI curve. In the case of a long-time (tens of hours) discontinuation of illumination, the anomaly was similar for all the portions of the PLI curve. The described results are explained by effect of two competing factors which are the luminescence fatigue and light-induced formation of unstable (molecular) chemical bonds that can transform to the stable atomic ones

Surgical management of a dog bite in a patient with comorbidities. Case study

Millions of people worldwide require urgent medical care annually due to bites and injuries inflicted by wild or domestic animals. Injured patients most frequently suffer from extensive and deep wounds resulting in traumatic shock of different degrees. The extensive wounds are characterized by severe damage to fascial muscles, tendons, bones, major vessels and nerve trunks. Therefore, the management of patients attacked by wild or domestic animals includes the elimination of life-threatening conditions and the application of various techniques and methods of reconstructive plastic surgery and their combinations to preserve the injured areas of the body (most commonly limbs). In each particular case, the prognosis and the choice of the most effective reconstructive surgery technique for the treatment of a wound defect depend on the state of the deep structures of the injured limb. The «reconstructive ladder principle» ensures the selection of the most appropriate treatment strategy, as it focuses on the nature of the injury and the patient’s overall health status, thus providing an adequate assessment of all possible surgical risks, general postoperative complications and challenges in wound healing. This algorithm allows prioritizing the most beneficial techniques from simple to difficult, as well as considering the «second line» methods. The «second line» methods are defined as simpler techniques that may be applied in case of some complications occurring after the administration of the primary method. Some additional difficulties may be experienced throughout the period of wound management in children and the elderly, in patients with complicated comorbidities and exacerbation of chronic diseases. This article presents a case study of a patient undergoing the treatment for an extensive and deep bite wound that is complicated by acute coronary syndrome and severe cardiogenic shock in the early postoperative period. Щорічно в світі до клінік невідкладної медицини звертаються десятки тисяч постраждалих з приводу укусів як домашніх, так і диких тварин. Дуже часто травмовані пацієнти мають значні за площею та глибиною рани та різний за ступенем тяжкості травматичний шок. Для великих укушених ран часто характерні тяжкі ураження фасцій, м’язів, сухожилок, кісток, магістральних судин і нервових стовбурів. Як наслідок, під час лікування постраждалих від нападу тварин нерідко доводиться усувати небезпечні для життя стани для збереження травмованих ділянок тіла (найчастіше — кінцівок), застосовувати різні техніки і методики реконструктивної пластичної хірургії та їх комбінації. Саме статус глибоких структур ураженої кінцівки найчастіше визначає прогноз у конкретному випадку та найперспективніший спосіб реконструктивного лікування ранового дефекту. Для вибору оптимальної тактики ведення укушених ран доцільно застосовувати «алгоритм реконструктивних сходинок». Його концепція враховує найімовірніші ризики під час оперативних втручань та післяопераційних ускладнень як з боку рани, так і щодо загального стану пацієнта, зумовлені характером ушкодження і актуальним статусом хворого. Зазначений алгоритм дає змогу обрати кращий із методів, розглядаючи їх за пріоритетом (від простішого до складнішого) та з урахуванням «резервних» методів. До останніх відносять простіші способи, які застосовують у разі появи ускладнень при використанні первинно обраного. Часто менеджмент пацієнта ускладнює дитячий або похилий вік, наявність складної супутньої патології, загострення хронічних захворювань під час лікування ран. Наведено випадок лікування великих глибоких укушених ран у пацієнта з виразною супутньою патологією

СТРУКТУРНО-ФУНКЦИОНАЛЬНЫЙ АНАЛИЗ ОПУХОЛЕВЫХ ГЕНОМОВ И РАЗРАБОТКА ТЕСТ-СИСТЕМ ДЛЯ РАННЕЙ ДИАГНОСТИКИ, ПРОГНОЗА ТЕЧЕНИЯ И ОПТИМИЗАЦИИ ТЕРАПИИ ЗЛОКАЧЕСТВЕННЫХ НОВООБРАЗОВАНИЙ

The article discusses results of the structural and functional analysis of molecular genetic abnormalities in various malignant tumors. Investigations have discovered more than 20 new markers for sporadic breast cancer. Several of them formed the test system, allowing the diagnosis with a specificity of 100%. Appearance of TMPRSS2/ERG4 chimeric gene is a frequent tumor-specific event, its expression is correlated with more aggressive forms of prostate cancer, may serve as a molecular marker for tumor cells and androgen assessment of tumor response to hormonal therapy. The effective systems for the early diagnosis of cervix and endometrium cancer were developed as well. Mutations in the VHL, deletions of chromosome 3 and methylation of several genes can predict the course and selection of effective therapy of clear cell kidney cancer. a number of molecular markers were identified for early diagnosis and prognosis of recurrence of bladder cancer. For diagnosis, prognosis and treatment of brain tumors we developed an effective complex system of markers. Protocol of molecular genetics investigation reveals the cause of the disease by more than 90% of patients with retinoblastoma. In order to study abnormal methylation in tumor genomes an innovative technology AFLOAT has been developed that allows to efficiently identify new markers with diagnostic value. Test systems of molecular genetic and epigenetic markers for early diagnosis and prognosis as well as for cancer therapy optimization have shown to be effective, have been approved for use in clinical practice and are being introduced into practical healthcare.Рассматриваются результаты структурно-функционального анализа молекулярно-генетических нарушений при различных злокачественных опухолях. Исследования позволили обнаружить более 20 новых маркеров для спорадического рака молочной железы, из которых сформированы тест-системы, позволяющие проводить диагностику со специфичностью 100%. Образование химерного гена TMPRSS2/ERG4 является частым опухоль-специфическим событием, его экспрессия коррелирует с более агрессивными формами рака предстательной железы может служить молекулярным маркером  андрогенчувствительности опухолевых клеток и оценки ответа опухоли на гормональную терапию. Разработаны эффективные системы для ранней диагностики рака шейки матки и эндометрия. Мутации гена VHL, делеции хромосомы 3 и метилирование ряда генов позволяет прогнозировать течение и подбор эффективной терапии светлоклеточного рака почки. Для ранней диагностики, прогноза течения и рецидивирования рака мочевого пузыря определен целый ряд молекулярных маркеров. Для диагностики, прогноза и лечения опухолей мозга разработана эффективная комплексная система маркеров. Протокол молекулярно-генетического  исследования позволяет обнаружить причину заболевания более чем у 90% пациентов с ретинобластомой.  Для исследования аномального метилирования в опухолевых геномах разработана инновационная технология AFLOAT, позволяющая эффективно выявлять новые маркеры, имеющие диагностическое значение. Тест-системы молекулярно-генетических и эпигенетических маркеров для ранней диагностики, прогноза течения и оптимизации терапии злокачественных новообразований показали свою эффективность, получили разрешение на использование в клинической практике и в настоящее время активно внедряются в практическое здравоохранение.

Nonlinear effects in resonant layers in solar and space plasmas

The present paper reviews recent advances in the theory of nonlinear driven magnetohydrodynamic (MHD) waves in slow and Alfven resonant layers. Simple estimations show that in the vicinity of resonant positions the amplitude of variables can grow over the threshold where linear descriptions are valid. Using the method of matched asymptotic expansions, governing equations of dynamics inside the dissipative layer and jump conditions across the dissipative layers are derived. These relations are essential when studying the efficiency of resonant absorption. Nonlinearity in dissipative layers can generate new effects, such as mean flows, which can have serious implications on the stability and efficiency of the resonance

Single shock and periodic sawtooth-shaped waves in media with non-analytic nonlinearities

The review of new mathematical models containing non-analytic nonlinearities is given. These equations have been proposed recently, over the past few years. The models describe strongly nonlinear waves of the first type, according to the classification introduced earlier by the authors. These models are interesting because of two reasons: (i) equations admit exact analytic solutions, and (ii) solutions describe the real physical phenomena. Among these models are modular and quadratically cubic equations of Hopf, Burgers, Korteveg-de Vries, Khokhlov-Zabolotskaya and Ostrovsky-Vakhnenko type. Media with non-analytic nonlinearities exist among composites, meta-materials, inhomogeneous and multiphase systems. Some physical phenomena manifested in the propagation of waves in such media are described on the qualitative level of severity

DETERMINATION OF DIRECTION TO RECONSTRUCTION OF GROUNDING SYSTEM

Purpose. In paper the most efficient and economical way for bringing the grounding system of power facilities into compliance with requirements of normative parameters was determined. Methodology. The determination was based on the comparison of the calculated values of touch voltage and length of additional electrodes for reconstruction of grounding system by two ways. To calculate the software based on the method of point current source which located in the three-layer soil, method guidance potential, Gauss method and the method of ordinary least squares was used. Results. For three possible cases amount of material and labor costs for the reconstruction and modernization of the grounding system while maintaining the equipotent grounding system and allowable touch voltage was defined. Originality. For the first time the effectiveness the reconstruction of grounding system for requirements of touch voltage, not to her of resistance, both in terms of electrical safety and in terms of material and labor costs proved. Practical value. The implementation of results saves a national scale funds for modernization and reconstruction of existing grounding systems of power facilities

Modification of structure and super conducting properties of Y-Ba-Cu-O films by laser emission

There was investigated the change of Y-Ba-Cu-O structure of monocrystallic films and polycrystallic facings under the effect of laser radiation (1,06 µm, 4 ms). The obtained results indicate the threshold character of changes of their superconductivy properties. As certain radiation energies it is possible to observe improvement of superconductivy properties