Lanthanum-Gallium Tantalate Crystals and their Electrophysical Characterization

Lanthanum-gallium tantalate single crystal (La3Ta0.5Ga5.5O14, langatate, LGT) is a perspective piezoe-lectric material as an active component of pressure sensors. An investigation of the growth conditions in-fluence (the growth atmosphere) on the electrophysical сharacterization of LGT, obtained in different at-mospheres (Ar, Ar + O2) was carried out. The frequency dependences of the relative dielectric constant (ε11/ε0) and of the admittance depend on the growth atmosphere. The langatate electrophysical сharacteri-zation in alternating electric fields were analyzed by means of the impedance spectr oscopy method. The behavior of short circuit currents in specimens of polar cuts of LGT single crystals with the same material electrodes without preliminary polarization is described. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3628

Changes of RB/ZR ratio in the forebrain in experimental blast-induced traumatic brain injury

Damage to the brain is a common cause of injuries, not only in combat but also in peacetime. It ranks second in the structure of morbidity after injuries to the extremities by shells. And due to recent events in Ukraine and around the world, the relevance of the study of the pathogenesis of blast-induced traumatic brain injury (bTBI) is growing.Of particular interest are changes in the balance of macronutrients and micronutrients in the brain. After all, it is known that their role is extremely important for the normal functioning of neurons, and the established imbalance is essential for the diagnosis and treatment of various diseases, including mild bTBI. The aim of the study was to establish changes in the ratio of Rb/Zr in the forebrain of rats with bTBI on the 1st day of the post-traumatic period

Changes of Rb/Sr ratio in the forebrain in experimental bTBI

Introduction. Explosive injury occurs due to the impact on the human body of the shock wave, toxic products of the explosion, shells, shrapnel from ammunition. The impact of the blast wave, as the main factor in the damage, causes changes in all body systems, but the most dangerous is brain damage. Even mild blast-induced traumatic brain injury (bTBI) leads to significant functional changes in the brain, in the pathogenesis of which biometals play an integral role, but this issue requires careful study. The aim of the study was to establish changes in the ratio of Rb/Sr in the forebrain of rats with bTBI on the 1st day of the post-traumatic period. Materials and methods: The study involved 12 adult male Wistar rats, weighing 220-270 g, aged 6-7 months, which were kept in standard conditions and diet of the DSMU vivarium

Экспериментальное исследование влияния ионизирующего излучения на минерализацию эмали различных функциональных групп зубов, как возможный этиологический фактор возникновения лучевого кариеса

Targets and goals. Using the method of Raman spectroscopy to study the mineralization of various anatomical and topographic zones of teeth of different functional groups before and after exposure to radiation factor at a dose of 2-70 Gy, to identify the degree of direct exposure to ionizing radiation on the tooth enamel. Methods. In this preclinical in vitro study on 40 model test objects of teeth removed according to clinical indications (incisors, premolars, molars) irradiated with an X-ray biological apparatus LNK-268 (RAP-100-10), voltage 70 kV, beam current 8 mA , dose rate of 22.7 Gy/min. The teeth were irradiated with a dose of 2 Gy, 20 Gy, 70 Gy and 110 Gy. Using the APK InSpectr M with a probe radiation wavelength of 532 nm, test objects (tooth enamel) measured the mineralization of the tooth enamel, using the intensity index of the Raman line hydroxyl appatite (x=963 cm-1) in relative units before and after irradiation of the teeth. At the same time was made the collection and processing of the information received. The measurements were carried out perpendicular to the tooth surface in the contact-stable position of the object (tooth) to the radiation source. To quantify the intensity of Raman radiation (in relative units), indicators at the maximum and minimum of the power of its Raman line and indicators of fluorescence intensity (M cf. relative) were measured as a test to assess the hygienic condition of the tooth surface). the difference obtained in the Raman line of hydroxy lappatite (relative units) was taken as the intensity of Raman for enamel, dentin and cement of the studied teeth (M cf.). Results. As a result, a qualitative and quantitative analysis of the content and distribution of hydroxyapatite in the structures of hard dental tissues (enamel, dentin, cement) was carried out before and after exposure to radiation factor in a dose of 2-110 Gr. There were no significant differences in the mineralization of hard dental tissues, regardless of the radiation dose. Conclusion. The high sensitivity and rapidity of the method was revealed, the possibility of quantitative processing of the results of the study online, which allows recommending it to assess the degree of mineralization/demineralization of the tooth, the effectiveness of remineralizing drugs and methods for their use, including for patients receiving radiation therapy for malignant tumors of the maxillofacial region.Цели и задачи. Методом Рамановской спектроскопии исследовать минерализацию различных анатомо-топографических зон зубов различных функциональных групп до и после воздействия лучевого фактора в дозе 2-70 Гр, выявить степень прямого воздействия ионизирующего излучения на эмаль зубов. Методы. В настоящем доклиническом исследовании in vitro 40 модельных тест-объектов зубов, удаленных по клиническим показаниям (резцы, премоляры, моляры), облучали на биологической рентгеновской установке ЛНК-268 (РАП-100-10; напряжение 70 кВ, ток пучка 8 мА, мощность дозы 22,7 Гр/мин). Облучение проводили в дозах 2, 20, 70 и 110 Гр. С помощью АПК «ИнСпектр М» с длиной волны зондирующего излучения 532 нм измеряли минерализацию эмали до и после облучения по показателю интенсивности Рамановской линии гидроксилапатита (х=963 см-1) в относительных единицах. Измерения проводили перпендикулярно поверхности зуба в контактно-стабильном положении зуба к источнику излучения. Для количественной оценки интенсивности Рамановского излучения (в отн. ед.) измеряли показатели в максимуме и минимуме мощности его Рамановской линии и показатели интенсивности флюоресценции (М ср. в отн.ед) как тест оценки гигиенического состояния поверхности зуба (по Александрову М.Т., 2008). Полученную разницу по Рамановской линии гидроксилапатита (отн. ед.) принимали за интенсивность Рамана для эмали, дентина и цемента исследуемых зубов (М ср.). Результаты. В исследовании проведен качественный и количественный анализ содержания и распределения гидроксилапатита в структурах твердых тканей зубов (эмаль, дентин, цемент) до и после воздействия лучевого фактора. Не выявлено существенных различий минерализации твердых тканей зубов независимо от дозы облучения. Заключение. Выявлена высокая чувствительность и экспрессность метода, возможность количественной обработки в режиме «онлайн» результатов исследования, что позволяет рекомендовать его для оценки степени минерализации/деминерализации зуба, эффективности реминерализирующих препаратов и методов их применения, в том числе для пациентов, получающих лучевую терапию по поводу злокачественных новообразований челюстно-лицевой области

New data on lithology, organic geochemistry and accumulation conditions of the Bazhenov formation in Western Siberia

This paper presents data on lithological composition, distribution, reservoir properties, geochemistry of organic matter and genesis of carbonate rocks of the Bazhenov formation within the central part of Western Siberia (the region of the Khantei hemianteclise). The following types of carbonates are distinguished: a) primary biogenic – shell rock interlayers and residues of coccolith; b) dia- and catagenetic – in varying degrees, recrystallized rocks with coccoliths, nodules and aporadiolarites; c) catagenetic – cracks healed with calcite in limestone of the foot of the Bazhenov formation. It was determined that the crystallization of the carbonate material of nodules took place in various conditions: in the bottom part of the sediments and in the later stages of diagenesis. The source of calcite for nodules was calcareous nanoplankton or bivalve shells. The carbonate content of the cuts decreases in the following sequence: Yuzhno-Yagunsky → Povkhovsky → Novortyagunsky → Druzhny areas, which are associated both with facial features and various physicochemical conditions of diagenesis and catagenesis. Transformation of organic matter increases in the northeast direction from South Yagunsky to Povkhovsky area, which is confirmed by molecular parameters of catagenesis. The carbonate rocks of the bottom part of the Bazhenov formation in the South Yagunsky area are similar in structure to the main oil-bearing reservoirs of the Salym and Krasnoleninsky fields

The historical essay of the department of Pathological Physiology of Dnepropetrovsk Medical Academy

The article presents historical information about the deve­lopment of the department of Pathological Physiology of Dnepropetrovsk medical academy, about chiefs of the depart­ment and their contribution to the development of the department from its foundation (1918) up to the present (2016). The areas of scientific research, the most significant achievements as well as changes in the provision of educational process are described