203 research outputs found
The value of polymorphism + 3725G / C TLR4 gene as a marker of liver fibrosis progression in patients with chronic hepatitis C
As a rule, chronic hepatitis C is manifested by the development of successive stages of liver fibrosis with the formation of eventually cirrhosis and liver cancer. However, in some patients the fibrosis progresses slowly, while in others there is a rapid formation of cirrhosis, which causes high mortality among such patients. According to published data, despite a fairly large number of studies regarding liver cirrhosis in chronic hepatitis C, factors contributing to liver fibrogenesis have not been definitively determined. The available data are quite contradictory. In this article, we review studies have assessed the TLR4 + 3725G/C gene polymorphism as a factor that may influence the rate of fibrotic progression. The research will build new approach for avoiding fast fibrogenesis
ЕФЕКТИВНІСТЬ ВИКОРИСТАННЯ АЛЬФАКАЛЬЦИДОЛУ ДЛЯ КОРЕКЦІЇ ВТОРИННОГО ГІПЕРПАРАТИРЕОЗУ У ХВОРИХ НА ХРОНІЧНУ ХВОРОБУ НИРОК У ДОДІАЛІЗНОМУ ПЕРІОДІ
Метою дослідження стало вивчення поширеності вторинного гіперпаратиреозу (ВГПТ) у хворих на ХХН в додіалізному періоді та дослідження ефективності лікування ВГПТ з використанням низьких доз активного метаболіту вітаміну Д – альфакальцидолу.
Матеріали та методи дослідження. Обстежено 45 хворих на ХХН в додіалізному періоді. Вивчали рівень паратгормону, загального та іонізованого кальцію, фосфору в сироватці крові, також визначали антропометричні показники. Отримані результати порівнювали із цільовими рівнями та залежно від стадії ХХН згідно з рекомендаціями NKF-K/DOQI 2003.
Результати дослідження. Рівень ПТГ в обстежених хворих коливався від 0,3 до 953,8 пг/мл, середній рівень становив – (234,49±34,99) пг/мл, середній рівень загального кальцію становив (2,08±0,06) ммоль/л, іонізованого кальцію – (0,74±0,07) ммоль/л, фосфору – (1,62±0,11) ммоль/л. Аналіз показників кальціє- фосфорного гомеостазу до й після лікування основної групи хворих під впливом лікування альфакальцидолом виявив достовірне підвищення рівня іонізованого кальцію та зниження рівня ПТГ на 51 %.
Висновки. Встановлено, що вторинний гіперпаратиреоз (ВГПТ) зустрічається у близько 65 % осіб в додіалізній стадії хронічної хвороби нирок. Визначено ефективність лікування ВГПТ низькими дозами альфакальцидолу, порівняно зі стандартною терапією карбонатом кальцію в загально прийнятій дозі. Доведено позитивну динаміку клінічних та біохімічних проявів ВГПТ під впливом лікування низькими дозами альфакальцидолу
Особливості транспорту заряду в полімерних композитах поліметилметакрилат – поліанілін
The influence of polymer matrix of polymethyl methacrylate (PMMA) on the specific conductivity, percolation threshold, energy of activation of charge transport in polymer composites PMMA − polyaniline (PAN) was studied.
Concentration dependence of the electrical conductivity of composites reveals percolation behavior with the low value of percolation threshold within 2 % content of polyaniline. It is found that in the polymer composites PMMA - PAN the specific conductivity increases by more than 8−9 orders of magnitude compared to the original matrix.
On the base of temperature dependence of the specific conductivity of the obtained composites, it is concluded that PMMA polymer matrix does not change the semiconductor nature of PAN conductivity in the composite but effects on the activation parameters of the charge transport.
From ESR spectra, it found that the presence of a polymeric matrix causes significant delocalization of the charge along the macrochains of the dielectric polymeric matrix.перколяції, енергію активації транспорту заряду в полімерних композитах ПММА– поліанілін (ПАН).
Встановлено, що в композитах ППМА – ПАН за наявності електропровідного полімеру питома провідність зростає більше ніж на 8−9 порядків порівняно з вихідною матрицею ПММА, при цьому концентраційна залежність електропровідності виявляє перколяційну поведінку із низьким значенням порогу перколяції в межах 2 % вмісту ПАН.
На основі температурної залежності питомого опору встановлено, що полімерна матриця ПММА не змінює напівпровідникового характеру провідності ПАН в композиті. але чинить вплив на активаційні параметри перенесення заряду.
З даних ЕПР спектроскопії встановлено, що наявність полімерної матриці зумовлює значну делокалізацію заряду вздовж макроланцюгів діелектричної полімерної матриці
Схеми гібридних приводів візків дощувальних машин із використанням альтернативних джерел енергії
Then analysis of the operation of modern multi-bearing sprinkling machines has shown that for irrigation needs and movement of sprinkling technics when in use for watering different types of drives and energy sources are used, in particular diesel fuel and electrical power.
Most sprinkling machines move whren irrigating with the help of electric motors of self-propelled carts, which are supplied by power generators of low power (up to 20 kW), which are driven by a diesel engine, and water to the car is fed from a stationary electrified pumping station.
There is an option for moving sprinkling machines with the help of hydraulic motors mounted on the carts, which are driven by hydraulic fluid supplied to them by a hydraulic pump from a diesel engine drive.
As the electrified pumping stations of irrigation systems were designed for the pressure of 0.6 … 0.8 MPa at the point of connection of a sprinkling machine, while today the sprinkling machines operate at pressure of 0.3 … 0.4 MPa, that is, there is a possibility of using the so-called excess pressure of 0.2 … 0,3 MPa for obtaining some additional energy at the place of connection of a sprinkling machine without redesigning and laying additional pipelines or power transmission lines. It is important to direct this extra energy for moving sprinkling machines.
The purpose of the research is to develop the circuits of hybrid drives with the use of alternative energy sources to reduce fuel consumption for irrigation by circular, frontal and frontal-circular sprinkling machines.
Analysis of previous research. In the course of previous research at the Institute of Water Problems and Land Reclamation of NAAS it has been established the possibility of using a full-flow hydro turbine as an energy source to feed the drives of the support carts of a multifunctional sprinkling electrified circular machines. The use of a full-flow hydro turbine, powered by the energy of irrigation water flow, makes it possible to do without a diesel generator, and thus without the fuel burn for its operation. Along with that, the sprinkling machines, whose power is provided only by the energy of irrigation water flow (from the irrigation pipeline), cannot move without performing watering. This is a disadvantage that prevents the implementation of technological regulations for watering by such types of sprinkling machines.
Research results. The results of the calculations of the power required for the movement of circular sprinkling machines of various modifications have shown that the use of excess energy of irrigation water in the pipeline at the input of a sprinkling machine with a hydroturbine drive, as a power source for the electric drive or the hydraulic drive for the movement of support carts, requires an increase in pressure in the irrigation network up to 4 m, and taking into account the possible losses of pressure at the connection points and in view of providing a water energy reserve the increase in pressure should be up to 10 m. In this case, the turbine drive with water consumption from 50 to 100 l / s can provide a power within the range of 4.0 to 8.0 kW.
Based on the results of the calculations, we obtained the initial data for the development of the circuits of hybrid drives of sprinkling machines at existing irrigation systems using alternative energy sources. Also we proposed different circuits of hybrid drives of carts, which can be applied on modern multi-support sprinkling machines.
Conclusions. 1. It has been established that modern sprinkling machines operate at a pressure of 0.3-0.4 MPa, while the existing electrified pump stations are designed for pressure in a closed irrigation network of 0.6-0.8 MPa, which gives the possibility of obtaining additional energy for moving sprinkling machines by means of a hybrid drive.
2. It has been established that a hybrid drive with a flow rate from 50 to 100 l/s can provide a capacity within 4.0-8.0 kW.
3. The turbine capacity for moving a sprinkling machine in length from 200 to 500 m, which should be up to 10 kW, has been grounded.
4. It has been obtained the initial data for the development of circuits of hybrid drives of sprinkling machine at the existing irrigation systems using alternative sources of energy. The flow rate of a sprinkling machine should not be less than 50 l/s and the minimum pressure at the connection point of a sprinkling machine should be 0.48 MPa.
5. The circuits of the hybrid drives of sprinkling machine carts with the use of a full-flow turbine have been developed, which will enable to increase the efficiency of existing irrigation systems by providing the excess energy of water pressure in the pipeline network of existing irrigation systems, as well as to provide energy and material resources savings in the range of 20-30%.Обґрунтовано вихідні дані щодо розроблення схем гібридних приводів дощувальних машин на діючих зрошувальних системах із використанням альтернативних джерел енергії.
Наведено схеми застосування повнопроточної гідротурбіни як джерела енергії для приводів опорних візків багатоопорних дощувальних маши
First Results of the Phase II SIMPLE Dark Matter Search
We report results of a 14.1 kgd measurement with 15 superheated droplet
detectors of total active mass 0.208 kg, comprising the first stage of a 30 kgd
Phase II experiment. In combination with the results of the neutron-spin
sensitive XENON10 experiment, these results yield a limit of |a_p| < 0.32 for
M_W = 50 GeV/c2 on the spin-dependent sector of weakly interacting massive
particle-nucleus interactions with a 50% reduction in the previously allowed
region of the phase space formerly defined by XENON, KIMS and PICASSO. In the
spin-independent sector, a limit of 2.3x10-5 pb at M_W = 45 GeV/c2 is obtained.Comment: 4 pages, 4 figures; PRL-accepted version with corrected SI contour
(Fig. 4
Highly efficient acoustooptic diffraction in Sn2P2S6 crystals
We have studied the acoustooptic (AO) diffraction in Sn2P2S6 crystals and
found that they manifest high values of AO figure of merit. The above crystals
may therefore be used as highly efficient materials in different AO
applications.Comment: 5 pages, 1 figur
Зміни показників фізичного стану жінок 19–35-літнього віку при самостійних заняттях оздоровчими видами фізичної культури
The article represents the comparative analysis results of physical data of 19–35 year-old women before and after 4 months self-training with using of different health-improving kinds of physical culture (athletic gymnastic, swimming, shaping).Представлены результаты сравнительного анализа морфофункциональных показателей женщин 19–35 лет до и после самостоятельных занятий различными оздоровительными видами физической культуры (атлетическая гимнастика, плавание, шейпинг).Сравнительный анализ показателей физического состояния до и после эксперимента выявил наличие общих и специфических особенностей проявления тренировочного эффекта в условиях занятий различными видами физической культуры.Надані результати порівняного аналізу морфо-функціональних показників жінок 19–35 років до та після занять різними оздоровчими видами фізичної культури (атлетична гімнастика, плавання, шейпінг). Порівняльний аналіз показників фізичного стану до і після експерименту виявив наявність загальних і специфічних особливостей прояву тренувального ефекту в умовах занять різними видами фізичної культури
First Dark Matter Limits from a Large-Mass, Low-Background Superheated Droplet Detector
We report on the fabrication aspects and calibration of the first large
active mass ( g) modules of SIMPLE, a search for particle dark matter
using Superheated Droplet Detectors (SDDs). While still limited by the
statistical uncertainty of the small data sample on hand, the first weeks of
operation in the new underground laboratory of Rustrel-Pays d'Apt already
provide a sensitivity to axially-coupled Weakly Interacting Massive Particles
(WIMPs) competitive with leading experiments, confirming SDDs as a convenient,
low-cost alternative for WIMP detection.Comment: Final version, Phys. Rev. Lett. (in press
Prospects for SIMPLE 2000: A large-mass, low-background Superheated Droplet Detector for WIMP searches
SIMPLE 2000 (Superheated Instrument for Massive ParticLE searches) will
consist of an array of eight to sixteen large active mass ( g)
Superheated Droplet Detectors(SDDs) to be installed in the new underground
laboratory of Rustrel-Pays d'Apt. Several factors make of SDDs an attractive
approach for the detection of Weakly Interacting Massive Particles (WIMPs),
namely their intrinsic insensitivity to minimum ionizing particles, high
fluorine content, low cost and operation near ambient pressure and temperature.
We comment here on the fabrication, calibration and already-competitive first
limits from SIMPLE prototype SDDs, as well as on the expected immediate
increase in sensitivity of the program, which aims at an exposure of 25
kg-day during the year 2000. The ability of modest-mass fluorine-rich detectors
to explore regions of neutralino parameter space beyond the reach of the most
ambitious cryogenic projects is pointed out.Comment: 19 pages, 10 figures included. New Journal of Physics, in pres
Regulation of free radical processes in healthy volunteers during experimental hyperthermia and in patients with coronary artery disease during summer heat waves
Background. In view of the worsening forecast for global temperature rise worldwide, it seems relevant to study the effects of abnormal heat waves on systemic regulatory processes in people with chronic diseases, in particular coronary artery disease (CAD).Aims. This study aimed to investigate the effect of hyperthermia on oxidative stress parameters in patients with various severity of CAD and in healthy subjects.Materials and methods. We studied the level of malonic dialdehyde (MDA) and the activity of Cu,Zn-containing superoxide dismutase (Cu,Zn-SOD) in healthy subjects under conditions of 30-day long simulated hyperthermia and in patients with different severity of CAD after the summer heat wavesResults. We revealed signs of oxidative stress in healthy volunteers during model hyperthermia that manifested as an increase in content of MDA in blood plasma. At the same time we observed increasing activity of Cu,Zn-SOD in erythrocytes that utilizes reactive oxygen species. The increase of Cu,Zn-SOD activity started with a certain latency what also can be explained by de novo enzyme biosynthesis induction. We also studied oxidative stress parameters in patients at high and moderate cardiovascular risk according to the SCORE risk chart with uncomplicated CAD course and in patients with complicated CAD with severe coronary damage according to angiography during the summer heat waves. We observed accumulation of MDA in blood plasma and increasing activity of erythrocyte Cu,Zn-SOD in patients with uncomplicated CAD. At the same time we noted that accumulation of MDA in blood plasma was not followed by any increase in activity of red blood cell Cu,Zn-SOD in patients with severe complicated CAD. This fact indicates dysregulation of free radical processes in patients with severe course of CAD during the heat waves.Conclusions. The dysregulation of free-radical processes in patients with a severe clinical course of CAD has been revealed
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