Ефективні епоксидні зв`язуючі і склопластики для відновлення та посилення будівельних конструкцій

A study of the effectiveness of surfactants and organosilicon substances use to improve the technological properties of epoxy binder, adhesion and strength properties and reduce the residual stresses of cured epoxy polymers in order to create an epoxy binder for the manufacture of the fiberglass. The optimal composition has been developed, which allowed to obtain glass-reinforced materials with high deformation and strength properties.Проведено дослідження ефективності застосування поверхнево-активних та кремнійорганічних речовин для покращення технологічних властивостей епоксидного зв’язуючого, адгезійно-міцнісних властивостей та зниження залишкових напружень отверджених епоксиполімерів з метою створення епоксидного зв’язуючого для виготовлення склопластиків. Розроблений оптимальний склад, що дозволив отримати склоармовані матеріали з підвищеними деформаційно-міцнісними властивостями

Vacancies and their complexes in FCC metals

The formation energies of vacancies and their complexes in copper and nickel at zero and finite temperatures are calculated by the embedded-atom method in the quasi-harmonic approximation. The role of temperature effects in the formation of various atomic configurations of intrinsic point defects is studiedyesBelgorod State Universit

Slope stability monitoring from microseismic field using polarization methodology

International audienceNumerical simulation of seismoacoustic emission (SAE) associated with fracturing in zones of shear stress concentration shows that SAE signals are polarized along the stress direction. The proposed polarization methodology for monitoring of slope stability makes use of three-component recording of the microseismic field on a slope in order to pick the signals of slope processes by filtering and polarization analysis. Slope activity is indicated by rather strong roughly horizontal polarization of the respective portion of the field in the direction of slope dip. The methodology was tested in microseismic observations on a landslide slope in the Northern Tien-Shan (Kyrgyzstan)

The Influence Of Avena Sativa Extract On Redox Processesand Fatty Acid Composition Of Lipids In Geese Tissues

The use of antioxidants in bird feeding helps to eliminate the harmful influence of negative factors of various etiologies. Feeding down the natural antioxidant additives has a number of advantages if compared with traditional synthetic additives. In the grass of common oat, in addition to known bioflavonoids, there were found more compound matters of phenol nature - avenantramids, which were characterized with 10-30 times higher antioxidant activity than other natural antioxidants. The purpose of this research was to find out the influence of the extract of common oat Avene Satíva on the state of the redox system and the fatty acid composition of the lipids of liver and heart tissues and skeletal muscle of the geese. In the day-old age, according to the principle of analogues, 2 groups of geese (control and experimental) were formed, each of them consisted of 26 birds. The aqueous solution of oat extract was added to the standard diet of the experimental group of geese from the 7th till the 56th day. This interval in the ontogenesis of geese includes periods of physiological stress due to the formation of a contour and juvenile feathers. The effectiveness of the Krebs cycle was evaluated by the activity of its dehydrogenases, antioxidant system was evaluated by the composition of the end products of lipids peroxide oxidation and the activity of antioxidant enzymes. At the same time, the fatty acid composition of lipids as a substrate of biological and peroxide oxidation was determined in these tissues. Coincidently, the live weight and the formation of the geese coat were controlled. It was established that oat extract stabilized the redox system of geese during the whole period of the experiment in all studied tissues. From the 28th day, the antioxidant activity of the tissues of liver and myocard of the experimental group of geese was significantly higher. At the end of the experiment, the unsaturation of fatty acids, which is defined as the total equivalent concentration of relatively multiple bonds, increased by 11.7% in the liver, by 7.22% - in the myocardium, due to the increase in the content of polyunsaturated fatty acids, primarily arachidonic (by 29.2% and 21.5% respectively), and in the liver the increase of docosahexaenoic acid was also observed (by 34.2%). The comparative analysis of the state of coat in the investigated groups of geese indicated the significant differences and confirms better results of the geese of the experimental groups. Thus, it is proposed to conduct similar research on wild species of birds, for which the state of feather coat plays a vital role

Fatty acid composition of tissue lipsds goslings and goose embryons

The changes in the fatty acid composition of the lipid in the brain tissues and geese liver and their embryos from 22-th embryonic day until 14-th day of postnatal period have been investigated. The fatty acid composition of tissues was quantified by methods of gas-liquid chromatography. The index of fatty acids unsaturation was calculated as equivalent concentration of unsaturated fatty acids relative to double bonds. Experience has shown that in the brain of geese high content of unsaturated fatty acids and level of their unsaturation occurs in 22-day-old embryos. From the 22nd to 28th day of embryogenesis the total content of unsaturated fatty acids in the brain tissues of embryos has decreased by 37.3 %, and the level of unsaturation of fatty acids — by 44.4 %. The transition to postnatal development (from the 28th day of embryogenesis to 1 st day of postnatal period) was characterized by a stable content of unsaturated fatty acids in the brain. However, the degree of unsaturation of fatty acids has decreased by 8.0 %. The content of unsaturated fatty acids in the liver of 22-days embryos compared with the brain tissues was higher by 13.9 %, while the level of unsaturation fatty acids in the liver, as compared with the brain was lower by 17.8 %. From the 22nd day of embryogenesis to the 1st day of postnatal development gradual increase in the content of unsaturated fatty acids in the liver was traced, while the level of their unsaturation in this period remained unchanged. A high content of unsaturated fatty acids was found in the liver of 1 day-old goslings, which is 15.8 % higher than the corresponding figure 22 day-old embryos. The first week of postnatal development was characterized by decrease in the content of unsaturated fatty acids in the liver by 25.0 %, and their level of unsaturation — by 21.62 %. The study results showed that one of the mechanisms of prooxidant- antioxidant balance support within the transition from of embryogenesis to postnatal development is to reduce the unsaturation of lipid fatty acids. This mechanism is realized in the brain of geese from hatching eggs of different quality. The support prooxidant-antioxidant balance in the liver by means of reducing the unsaturation of fatty acids is less effective and is mostly defined by fatty acid composition of lipids of geese hatching eggs

ПІДВИЩЕННЯ ЕФЕКТИВНОСТІ ЕЛЕКТРОКОАГУЛЯЦІЙНОЇ ОЧИСТКИ СТІЧНИХ ВОД МОЛОКОЗАВОДІВ ШЛЯХОМ ДОДАВАННЯ ЛУГУ

Experimental studies have been conducted to increase the efficiency of electrocoagulation treatment of dairy wastewater by adding alkali of different chemical nature and physical states. The comparative characteristics of the use of sodium hydroxide NaOH (in the form of 5% aqueous solution) and calcium oxide CaO (in the form of powder) are given. It has been shown that the use of CaO is more effective. It is established that the addition of CaO powder to wastewater after electrocoagulation to pH = 9.0-9.5, compared with NaOH solution, can increase the degree of purification by the following indicators: chemical oxygen demand (COD), transparency, orthophosphate ion concentration (PO43-), the concentration of ammonium ions (NH4+). This completely removes the ether-soluble substances (ESS). It was found that the addition of CaO after electrocoagulation can reduce the density of electric current from 50 A/m2 to 30 A/m2 (40%). The degree of purification remains quite high (98-99%). This saves electricity and has a positive effect on the environmental and economic assessment of technology. It is established that the following technological parameters are optimal for electrocoagulation wastewater treatment of dairies: electric current density 30-50 A/m2; processing time 5-7 minutes; the amount of CaO 0.5 g/dm3; pH of water after alkalization 9.0-9.5. As a result of the conducted research regularities of influence of the quantity of the added CaO and indicator of pH of sewage on the volume of the formed slime after electrocoagulation are established. Mathematical dependences of this influence, which have a polynomial character, are determined. It is proved that the use of powdered CaO in comparison with the use of NaOH solution can improve the physicochemical properties of the formed sludge. This is due to the nature of the added alkali, as well as the fact that solid crystalline particles of CaO, adsorbed on amorphous particles of coagulant, cause increased ability of sludge to sedimentation and compactionПроведені експериментальні дослідження щодо підвищення ефективності електрокоагуляційної очистки стічних вод молокозаводів шляхом додавання лугу різної хімічної природи та агрегатного стану. Наведена порівняльна характеристика застосування натрію гідроксиду NaOH (у вигляді 5% водного розчину) та кальцію оксиду СаО (у вигляді порошку). Показано, що використання CaO є більш ефективним. Встановлено, що додавання в стічну воду порошку CaO після електрокоагуляції до рН = 9,0-9,5, в порівнянні з розчином NaOH, дозволяє підвищити ступінь очистки за такими показниками: хімічне споживання кисню (ХСК), прозорість, концентрація ортофосфт-іонів (PO43-), концентрація іонів амонію (NH4+). При цьому практично повністю видаляються етеророзчинні речовини (ЕРР). Встановлено, що додавання CaO після електрокоагуляції зменшує густину електричного струму з 50 А/м2 до 30 А/м2 (на 40%). При цьому ступінь очистки від усіх досліджених забруднювачів залишається достатньо високим (98-99%). Це забезпечує економію електричної енергії та позитивно впливає на еколого-економічну оцінку технології. Встановлено, що для електрокоагуляційної очистки стічних вод молокозаводів оптимальними є такі технологічні параметри: густина електричного струму 30-50 А/м2; час обробки стічної води 5-7 хвилин; кількість доданого СаО 0,5 г/дм3; рН води після підлужування 9,0-9,5. В результаті проведених досліджень встановлені закономірності впливу кількості доданого СаО та показника рН стічної води на об’єм утвореного шламу після електрокоагуляції. Визначені математичні залежності цього впливу, які мають поліноміальний характер. Доведено, що використання порошкоподібного CaO в порівнянні з застосуванням розчину NaOH дозволяє покращити фізико-хімічні властивості утвореного шламу. Це пов’язано з природою доданого лугу, а також з тим, що тверді кристалічні частинки CaO, адсорбуючись на аморфних частинках коагулянту, зумовлюють підвищену здатність шламу до седиментації та ущільнення

C-fos expression and cell proliferation in mice after exposure to nanosecond repetitively-pulsed X-rays

В статье указано Rostov, Vladimir V

Dissolved organic matter and microbial carbon of Protocalcic Chernozems of different land management

Water-extractable organic matter is the most active and mobile form of soil carbon. The other active fraction and extremely biolabile is the carbon constituent of microorganisms. Both of these fractions play an essential role in agrocenoses and in the global carbon cycle on our planet. The aim of the work was to estimate the carbon content of water-extractable organic matter as well as that of microbial origin in typical chernozems (Protocalcic Chernozems) of different land-use types. Protocalcic Chernozem samples taken from the fields of long-term experiments with different types of land use were investigated: a permanent bare fallow for 55 years (since 1964); conventional tillage – four-field crop rotation, first rotation; direct seeding – crop rotation similar to direct seeding, first rotation; a 21-year fallow (since 1998) after 34 years of bare fallow (since 1964). We determined the carbon content of water-extractable organic matter and the carbon content of microbial origin. In the studied series of variants, the proportion of carbon of water-extractable organic matter in the total amount of organic matter in the upper horizon (0–15 cm) was 0.69, 0.85, 1.01, and 0.98%, respectively, while that of carbon of microbial origin was 0.27, 0.55, 0.53, and 1.52%. It was noted that against the background of increasing the content of total organic carbon in direct seeding variant, compared with the traditional soil treatment, the microbial biomass in this variant does not increase. The fallow variant, unlike all other types of land use, is characterized by a higher proportion of microbial carbon, in contrast to the carbon of water-extractable organic matter

The role of cardiac MRI in risk stratification for sudden cardiac death in patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a prevalent genetic heart disease with a worldwide prevalence. Its estimated incidence in young individuals is approximately 1 case per 500 population. HCM in adults can be clinically diagnosed through visualization, either via 2D echocardiography or cardiac magnetic resonance (CMR) imaging, where the maximum thickness of any left ventricular (LV) segment, measured in end-diastolic phase, is 15 mm in the absence of other hypertrophy causes. Aim. To demonstrate the role and diagnostic capabilities of CMR as a powerful diagnostic tool for detecting and evaluating sudden cardiac death (SCD) risk factors in patients with HCM. Materials and methods. From January 2022 to September 2023, 236 CMR examinations were conducted and analyzed at the Diagnostic Radiology Department of Amosov National Institute of Cardiovascular Surgery in patients with suspected HCM. All examinations were performed on a magnetic resonance tomograph “Toshiba Vantage Titan 1.5T” until May 2023, and “Canon Vantage Orian 1.5T” from May to September 2023, with ECG and respiratory synchronization as well as intravenous injection of gadolinium-based contrast agent (Gadovist 1.0) at a dose of 0.1 mL/kg body weight. Statistical and mathematical data processing was performed by using the Statistica 6.0 (StatSoft Inc., USA) application package. Results. The mean age of the examined patients was 41 ± 28 years, there were 142 male (60 %) and 94 (40 %) female patients. Symmetric non-obstructive HCM was identified in 39 patients (16.5 %) and 184 patients (78.0 %) had asymmetric obstructive HCM. Apical HCM was diagnosed in 4 patients (1.5 %), and midventricular HCM – in 9 patients (4.0 %) including one patient with a combination of midventricular and apical forms. Risk factors for SCD were identified in 60 patients (25.4 %) with myocardial thickness exceeding 30 mm, 8 patients (3.3 %) with apical aneurysm, 4 patients (1.6 %) with reduced LV systolic function (LV ejection fraction <50 %), and 164 patients (69.4 %) with pathological late gadolinium enhancement. Conclusions. CMR is a modern, high-precision and powerful diagnostic method that plays a key role in identifying and assessing SCD risk factors in patients with HCM. CMR helps to identify HCM patients at high SCD risk who may benefit from preventive measures such as implantable cardioverter-defibrillator therapy

NOVOSIBIRSK REGION PROGRAM OF THE LIVER TRANSPLANTATION IN CHILDREN

The aim of the study was to analyze the early and late outcomes of pediatric liver transplantation (LTx) program in the Novosibirsk region. Material and Methods. The retrospective study included 24 patients aged 72 ± 74.8 months (from 4 to 212 months, median – 20 months) with a body weight of 21.7 ± 18.1 kg (from 4.5 to 55 kg, median – 12.5 kg). Two (8.3 %) cadaveric whole liver grafts, 19 (79.2 %) living donor liver grafts, and 3 (12.5 %) cadaveric liver fragments (reduced-size or split-liver) were transplanted. Results. The features of vascular and biliary reconstruction in different types of LTx are discussed. The incidence of vascular and biliary complications was 8.3 and 20.8%, respectively. The patients stayed in the intensive care unit for 9 ± 5.1 days (from 4 to 22 days, median 8 days) and total length of hospital stay was for 40 ± 25.4 days (from 19 to 136 days, median 32 days). Two (8.3 %) recipients had early graft dysfunction. Perioperative mortality (up to 90 days) was absent. The overall 5-year patient and graft survival rates were 95 and 88 %, respectively. Conclusion. The Novosibirsk region has a pediatric LTx program with outcomes comparable to the data of the leading world and Russian centers