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The results of experimental data of studies of reinforced concrete structures made of light high-strength concrete in a wide range of reinforcement coefficients (0.015-0.036) are presented. Experimental studies of a series of beam-type reinforced concrete structures made of light high-strength concrete were carried out according to the fi rst and second groups of limiting states to substantiate the use of such structures in hydraulic engineering. It should be noted that the complex technical solutions for a floating bulkhead are under development for the construction of a gravity-type foundation (including an abutment in an earth dam). Recommendations on the use of the obtained results of experimental studies in hydraulic engineering building including when designing a reinforced concrete structure of a dry floating bulkhead for the construction of a gravity-type foundation made of lightweight high-strength concrete are given.

Experimental data demonstrate dependence of wave breaking type on wave amplitude-frequency-phase structure that is determined by nonlinear wave transformation. The spilling and plunging breaking waves are differed in the symmetry of the wave profile and the ratio of the amplitudes of the 1st and 2nd harmonics in breaking wave. The wave profile symmetry, in turn, is determined by the phase shift between these harmonics. In spilling breaking waves, it is close to zero, which corresponds to symmetrical waves. In plunging breaking waves, the phase shift is negative, which corresponds to the forward shifted 2nd harmonic. The ratio of the amplitudes of the 1st and 2nd harmonics in spilling breaking waves is less than that in plunging breaking waves. The periodic energy exchange between harmonics during near resonant triad wave interactions is the reason for the change in the types of wave breaking for waves propagating above a gentle inclined bottom. Due to the different structure, plunging breaking waves contribute to the erosion of the cross-shore underwater profile, while spilling breaking waves contribute to the accumulation of sand on it.

The goal of this study was to describe and validate a muscle specific method to evaluate the anaerobic threshold in a working muscle based on the simultaneous measurement of EMG activity and the deoxyhemoglobin content (ATHHb-EMG). The study involved males with different fitness levels. During the cycling (n = 40) and ski double poling (n = 9) incremental ramp tests, blood lactate concentration, and muscle deoxyhemoglobin content and EMG activity were measured. Some participants were involved in the cycling test-retest study (n = 11). In cycling and double poling tests, close and significant correlations (r = 0.89 – 0.92, P < 0.002) were found between lactate threshold (a marker of the anaerobic threshold at the organism level) and the ATHHb-EMG (a marker of the AT at the working muscle level). The coefficient of variation of the ATHHb-EMG in the cycling test-retest was low (~3%). The muscle specific ATHHb-EMG demonstrates low variability and is appropriate to detect the fitness level and training-induced increase in aerobic performance in a working muscle. The emergence on the market of miniature EMG amplifiers and near-infrared spectrometers opens wide possibilities for using our method in laboratory studies and in field tests.

Based on the data of Voluntary Observing Ship (VOS) Program of the Black Sea waves in 1950–2007, the wave climate variability and its relation to the main climatic indices is analyzed by the example of the maximum annual wave heights. Climatic indices characterizing the North Atlantic, Atlantic Multi-Decadal and Pacific Decadal oscillations, as well as fluctuations of the East Atlantic-Western Russia teleconnection pattern are considered. It is shown that the methods based on the wavelet analysis, particularly the spavlet analysis and the method of the wavelet correlations proposed by the authors, have doubtless advantages since they permit to reveal fine structure of the nonstationary process in variability both of the wave heights and the climatic indices, the features of various fluctuations’ periods, and to analyze relationships between the climatic indices’ changes and the wave heights. Due to these methods, determined are the main periods of variability in the anomalies of the maximum annual wave heights associated with a) the North Atlantic Oscillation (about 28–25, 14–16 and 6–6.5 years); b) the Atlantic Multi-Decadal Oscillation (50, 25 and about 14–16 years); c) the Pacific Decadal Oscillation (about 12.5–10 years) and d) the East Atlantic-Western Russia pattern fluctuation (about 66–67, 14–16 and 7–7.5 years). Significant low-frequency impact of fluctuations of the East Atlantic-Western Russia teleconnection pattern upon the Black Sea wave climate is shown for the first time.

The article analyzes a number of indicators characterizing the environmental and economic state of the region. It is established that the state of the environment has already moved from the category of exogenous parameters for the economic system into the category of intra-economic characteristics, which, first of all, changes the structure and nature of methods of analysis and assessment of the impact of pollution on the environment. The method of hierarchical analysis, which allows to systematize the elements of environmental and economic security of the region, is applied. The mathematical support of the method of analysis hierarchies is considered. To assess the quality of environmental and economic security of the region a hierarchy is built, which provides for the allocation of the criteria of the upper and lower levels. It is proved that the economic basis of regional environmental-economic interests is the ownership of natural resources, and the environmental basis is the integrity of ecosystems in the region. It is proved that the formation and improvement of the mechanism of security should be based on the coordination of environmental and economic interests and the resolution of contradictions between them. The authors proposed an original software product for the justification of the safety parameters of ecological and economic systems. The structure and parameters of the developed decision support system, allowing to carry out the convolution of the group of economic and environmental factors that influence the quality of management decisions, are considered. The hierarchical model built allows the decision maker to form a system of ranked indicators that determine the level of environmental safety of regional environmental-economic systems, and provide a reasoned choice of project alternatives.

Based on experimental data, we study the possibility of parametrizing the spatial variation in the phase shift (biphase) between the first and second nonlinear harmonics of wave motion during wave transformation over an inclined bottom in the coastal zone. It is revealed that the biphase values vary in the range [–π/2, π/2]. Biphase variations rigorously follow fluctuations in amplitudes of the first and second harmonics and the periodicity of energy exchange between them. Wave breaking influences the biphase value, retaining its variations in the negative domain in the range [–π/2, 0]. The formula applied in modern practice to calculate the biphase, which depends on the Ursell number, is incorrect for calculating the biphase for wave evolution in the coastal zone, because it does not take into account periodic energy exchange between the nonlinear harmonics. We propose a linear approximation of the biphase values from the size of the ratio of the current distance to the coast to the possible spacial duration of the exchange period, which is determined by the dispersion relation. We reveal the dependence of biphase variations on the wave transformation scenario and demonstrate the possibility of constructing a separate parameterization of the biphase for each scenario. Our research and the obtained biphase parameterizations can be used to simulate the sea state in the coastal zone, as well as in problems of predicting the development of coasts under the impact of storm waves.

The outcomes of our laboratory experiments corroborate hypotheses advanced earlier, dedicated to the mechanism of origination of abnormally high waves under the development of spectral instability. We have clarified the characteristics of spectral instability development including the dependences of the value of the downshift of the spectral maximum and distances at which it occurs on the steepness of waves and width of the initial spectrum. In addition, we have revealed the dependence of the number of abnormal waves on the fraction of spectral energy transferred to the low-frequency range and on the stage of spectral instability development. Our results offer the basis for creating a statistical model of the origination of abnormally high waves.

The ultrasound treatment of curved contours and complex surfaces is considered. Appropriate design approaches are discussed. As examples, automated ultrasound treatment processes are presented.

The regularities of the local reflection of long waves from underwater slopes with different inclinations were investigated using the data of a laboratory experiment that was performed at a scale of 1 : 20 compared to the full-scale conditions. It is shown that the coefficient of the local reflection of waves decreases with the distance from the coast. The dissipation of the wave energy significantly reduces the local reflection coefficient near the shoreline and at the most remote sea point of the underwater slope. This leads to the existence of maximum of the local reflection coefficient at the boundary of the wave breaking. The presence of peculiarities of the bottom topography, such as an underwater bar or trench, can also significantly change the local reflection coefficient and influence its values in the offshore part of the underwater slope.

On the basis of field experiments and numerical modeling, we show that coastal zones are classifiable according to manifestations of wind wave nonlinearity, which herein is recognized as periodic energy exchange between the first and second nonlinear wave harmonics depending on the average bottom slope and the Iribarren and Ursell numbers. The results offer a basis for developing vulnerability criteria for the coastal zone taking into account its nonlinear dynamics.

We show the possibility of obtaining UV luminescence from 5d-4f transitions of rare-earth ions in the BaY2F8: (Yb3+, Pr3+, Ce3+) crystal under upconversion excitation by standard laser diodes with lasing wavelengths of 960, 808, and 840 nm. Various upconversion mechanisms of pumping for populating the higher-lying energy levels of the active ions, as well as methods of adaptation of the active medium BaY2F8: (Yb3+, Pr3+, Ce3+) to these mechanisms, are considered.

Цель: Изучить эффективность золедроновой кислоты в терапии постменопаузального остеопороза (ПМО) с учетом полиморфизма гена фарнезилдифосфат-синтетазы (FDPS). Методы исследования: клинический, определение биохимических маркеров костного метаболизма (БМКР) - электрохемилюминесцентным методом («Хоффманн-Ла Рош ЛТД», Швейцария). Измерение МПК проводили с помощью двухэнергетической рентгеновской абсорбциометрии позвонков поясничной области (L1-L4) и шейки бедренной кости (Neck left, Neck total left). Молекулярно-генетический (определение однонуклеотидного полиморфизма гена FDPS (rs2297480) - методом «примыкающих проб» с анализом кривых плавления (ЗАО «НПФ ДНК-Технология, Россия)). Результаты. Обследовано 225 женщин с постменопаузальным остеопорозом. Средний возраст составил 59 (5466) лет. Средняя продолжительность периода постменопаузы 7 (2-13) лет. ИМТ=27,2(23,6-29,05) кг/м2. Распределение аллелей (АА:АС:СС) составило 55,1(n=144):39,5(n=103):5, 4(n=14). Базальные уровни биохимических маркеров костного ремоделирования (БМКР) соответствовали периоду постменопаузы и статистически значимо не различались в зависимости от генотипа FDPS. Средние показатели МПК в поясничном отделе позвоночника и/или шейке бедра соответствовали остеопорозу. Всем пациенткам проводили терапию золедроновой кислотой (zol) в дозе 5 мг в виде внутривенной инфузии 1 раз в 12 месяцев в течение 2 лет. Дополнительно все пациенты получали кальций 1000 мг/сут и витамин Д3 800МЕ/сут. Реакция БМКР на инфузию zol различалась в зависимости от генотипа FDPS. Через 6 месяцев после 1-ой инфузии достоверно более выраженное снижение B-Crosslaps 92 (91-93)% отмечено у пациентов с С/С генотипом (p=0,056), по сравнению с 82% у носителей аллеля А (p=0.07). Через 9 месяцев после инфузии B-Crosslaps у носителей аллеля А повышались до 75%, остеокальцина - 44,4% от исходного. Тогда как у носителей генотипа C/C как B-Crosslaps - (87%), так и osteocalcine -(53,6%) оставались по-прежнему низкими (р=0,056). К 12 месяцу после инфузии уровни B-Crosslaps и osteocalcin у носителей аллеля A повышались и соответствовали премено-паузальным значениям, тогда как у носителей С/С генотипа оставались в пределах ниже нижней границы нормы для пременопаузы. У пациентов с СС генотипом на фоне выраженного снижения БМКР после 2ой инфузии золедроновой кислоты произошло снижение МПК на 5,6%. Выводы. Различная реакция на терапию золедроновой кислотой у пациенток с ПМО связана с полиморфизмом гена FDPS (rs2297480). Для пациентов с генотипом С/С характерно «гиперторможение» костного обмена в ответ на терапию золедроновой кислотой, что возможно, было причиной отрицательной динамики МПК в поясничном отделе позвоночника на втором году терапии золедроновой кислотой.

Osteoporosis and atherosclerosis are the most socially significant chronic non-infectious diseases. This is due to their high prevalence and medical, social and economic consequences from osteoporotic bone fractures and myocardial infarction and stroke as a result of cardiovascular diseases (CVD). The level of estrogen is essential for the formation and maintenance of bone mass in women. The sharp decline in estrogen levels after bilateral ovariectomy plays the role of trigger factor in the development of complex disorders of the bone and the cardiovascular system. Pathogenetically justified approach to the correction of the estrogen-deficient states is the use of hormone replacement therapy (HRT). To study the effect of HRT on the cardiovascular system and bone mineral density (BMD) we examined 50 women with surgical menopause which received HRT for more than a 10-year period. We studied the anthropometric and biochemical parameters (blood cholesterol and its fractions, fasting blood glucose), performed Doppler ultrasonography of head and neck vessels with measurement of pulse velocity, dual-energy x-ray absorptiometry (DEXA) for BMD estimation. Examination was carried out twice - in the early period after the operation (the first year) and after 10 years. Analysis of the cardio-vascular system and the BMD has demonstrated more severe atherosclerotic vascular changes and a greater decrease in BMD in patients who discontinued use of HRT. The severity of atherosclerosis and the level of the BMD were dependent on HRT use.

Results of comparative study of cryoplasmic therapy applied at complex treatment of 168 patients with disseminated intravascular coagulation syndrome were presented. In 56 patients complex therapy included cryosupernatant plasma (CSNP) and 112 patients received fresh frozen plasma (FFP). Study of coagulation and fibrinolysis system showed that restoration of fibrinolysis activity, physiologic anticoagulants and normalization of plasma fibrinogen levels occurred sooner when CSNP was used. Application of CSNP promoted the relaxation of disease severity, prevention of thrombotic complications and decrease of lethality (by 14.2%) to a greater extent as compared to FFP use.

Continuous wavelet analysis was used to study the spectral characteristics of the m. vastus lateralis electromyographic activity in two I : rhythmic knee-joint extensions and cycling. Wavelet analysis of surface electromyograms (EMGs) recorded during cyclic contractions of the same muscle during the two types of movements showed differences in the pattern of changes in the timefrequency characteristics of the signal during a single cycle of movements with different loads, as well as differences in the slow variations of spectral characteristics related to the development of muscle fatigue during the tests. It was shown that, during cycling at low loads (the beginning of the test) the EMG activity peaked during the second half of the muscle contraction (the angle in the knee joint was ≈140°); the increase in the load at the end of the test led to a shift of the peak to the beginning of the active phase of movement, while the median frequency of the instant wavelet spectra during the muscle contraction remained almost unchanged. During knee-joint extension, the maximum EMG activity was observed at the very end of the active phase of movement for all loads, and the median frequency significantly increased with increasing angle at the knee joint. The long-term time course of the EMG intensity growth during these tests also differed, whereas the changes in the wavelet-spectrum median frequencies were practically the same: they increased during both tests.

The spatio-temporal variability of individual storm waves in the coastal zone is studied. Wave chronograms were presented as sums of the first and second harmonics with amplitudes slowly varying in time, which are envelopes for the waves of the corresponding frequency bands. The amplitude-frequency structure of individual waves was estimated from the variations in the amplitude of the envelopes. Bi-spectral analysis was applied to estimate the phase composition of the waves. It is shown that, in the initial stage of transformation, the fluctuations of the waves of the first and second harmonics are synchronous. The amplitudes of the second harmonics are proportional to the squared amplitudes of the first harmonics. Thus, a simple model is possible for the description of individual waves based, for example, on the generalization of the Stokes theory. As the waves approach the coast, the ratio of the amplitudes of the first and second harmonics in individual waves varies in time chaotically, thus it is not possible to describe individual waves on the basis of a simple model. The main cause of the chaotic variation of the amplitudes is the backward transfer of energy from the highest harmonics to the first harmonics due to the sub-near resonant triad interaction close to the resonance. The phase composition of individual waves depends on the distance propagated by the waves and on the stage (main or backward) of the energy exchange between the nonlinear harmonics.

Цель: провести анализ переносимости терапии золедроновой кислотой у постменопаузальных женщин с остеопорозом. Материал и методы. В открытое проспективное исследование в течение 36 месяцев были включены женщины с постменопаузальным остеопорозом, получающие терапию золедроновой кислотой (n=225). Проводились оценка соматического статуса, лабораторные и инструментальные исследования (клинический анализ крови, биохимический анализ крови, общий анализ мочи, биохимические маркеры костного ремоделирования (БМКР) сыворотки крови: B-CrossLaps - маркер резорбции, остеокальцин - маркер костеобразования, остеоденситометрия (двухэнергетическая рентгеновская абсорбциометрия) определение минеральной плотности кости (МПК) в поясничном отделе позвоночника (L1-L4) и шейке бедра (Neck). Результаты. 225 женщин с диагностированным постменопаузальным остеопорозом, получали антирезорбтивную терапию золедроновой кислотой (ЗК) (5 мг, в/в, капельно, 1 раз в год). Дополнительно из этой когорты были сформированы подгруппы женщин, которым проводили в/в инфузию во второй (n=90) и в третий (n=30) раз. Медиана возраста обследованных составила 59 (54-66) лет. Наиболее частыми нежелательными являются симптомы реакции острой фазы: гриппоподобный синдром, костно-мышечные проявления, гипертермия, слабость. Причем, у всех пациентов СРОФ развились, через 12-24 часа после инфузии ЗК. В день проведения внутривенной инфузии и последующие 2 дня 48,9% (n=110) пациентам проводили профилактику реакции острой фазы (РОФ) парацетамолом по схеме: 1000 мг х 3 р/д, 3 дня. Среди тех, кому не проводили профилактику, РОФ развилась у 65,3% (n=75) и у 34,7% (n=40) пациенток нежелательных явлений отмечено не было. В общей сумме, у 48,4% (n=109) пациенток были зафиксированы симптомы реакции острой фазы различной тяжести. В структуре РОФ преобладали слабость-26%, озноб - 23,4%, боли в костях и мышцах - 28,4%, гипертермия - 20,9%. Продолжительность симптомов РОФ у пациенток без профилактики СРОФ до 3 дней отмечена у 68% (n=51), 3-7 дней у 25,3% (n=19), более 7 дней у 6,7% (n=5). У большинства пациенток без профилактики (77,3%) отмечалась легкая степень тяжести симптомов, 2-средняя степень тяжести диагностирована у 16% (n=12) пациенток и 3-тяжелая степень проявлений РОФ была отмечена у 6,7% (n=5). Симптомы РОФ (СРОФ) на фоне профилактики развивались в 1,7 раз реже и отмечались у 39% (n=43) пациенток. У пациенток, которым проводили профилактику, продолжительность СРОФ до 3 дней, наблюдалась у 67,4% (n=29) и 3-7 дней у 32,6% (n=14). После проведения профилактики нами была зарегистрирована в основном легкая 62,8% (n=27) и умеренная степень тяжести СРОФ - 34,9% (n=15). Тяжелая степень РОФ отмечена только у 1 пациентки (2,3%). В структуре РОФ преобладали слабость, озноб, боли в костях и мышцах, гипертермия (р