16 research outputs found
НЕЙРОПРОТЕКТИВНЫЕ ЭФФЕКТЫ СУЛЬФАТИРОВАННЫХ ПОЛИСАХАРИДОВ ИЗ МОРСКИХ ВОДОРОСЛЕЙ
Currently, neurodegenerative diseases (NDD) occupy a significant place in the structure of disease of the elderly, which dictates the need to find new and effective treatment and prevention of this pathology. At the heart of NDD development is a violation of the metabolism and the conformational change of cellular proteins with subsequent accumulation and aggregation of their in certain groups of neurons. The immediate cause of the death of the affected neurons in NDD is initiated by intracellular proteins apoptosis, during which a large number of neurotransmitter glutamate is released. The consequence of an imbalance in the synthesis and release of neurotransmitters are related the memory impairment, motor coordination and cognitive abilities of human. Based on the analysis of the extensive literature domestic and predominantly foreign authors of the last decade the modern data on the effect of sulfated polysaccharides (SPS) of algae in vivo and in vitro in degenerative processes of the nervous system. Found that due to its multi-point impact, SPS have on the body antioxidant, anti-inflammatory, antiapoptotic, antihyperlipidemic, anti-toxic effects. Consequently, SPS can arrest a number of secondary pathological effects observed in neurodegenerative diseases (oxidative stress, inflammation, the phenomenon of increased neuronal apoptosis, toxic effects etc.). Varieties of pathogenic mechanisms underlying NDD makes possible the combined use of neuroprotective compounds acting sequentially in different stages of a pathological process. Accumulated a lot of experimental evidence to assume that the SPS may be the basis for the creation of next-generation drugs for the treatment of neurodegenerative diseases. В настоящее время нейродегенеративные заболевания (НДЗ) занимают значительное место в структуре заболеваемости лиц пожилого возраста, что диктует необходимость поиска новых эффективных средств лечения и профилактики этой патологии. В основе развития НДЗ лежит нарушение метаболизма и изменение конформации клеточных белков с последующим накоплением и агрегацией их в определенных группах нейронов. Непосредственной причиной гибели пораженных нейронов при НДЗ является инициированный внутриклеточными белками апоптоз, в ходе которого освобождается большое количество медиатора глутамата. Следствием дисбаланса в синтезе и выделении соответствующих нейромедиаторов являются нарушения памяти, координации движений и мыслительных способностей человека. На основании анализа обширной литературы отечественных и преимущественно зарубежных авторов последнего десятилетия представлены современные данные о действии сульфатированных полисахаридов (СПС) из морских водорослей in vivo и in vitro при дегенеративных процессах нервной системы. Установлено, что благодаря своему многоточечному воздействию, СПС оказывают на организм антиоксидантное, противовоспалительное, антиапоптотическое, антигиперлипидемическое, антитоксическое действие. Вследствие этого СПС могут купировать ряд вторичных патологических эффектов, наблюдаемых при нейродегенеративных заболеваниях (окислительный стресс, воспалительный процесс, явление повышенного апоптоза нейронов, токсические эффекты и пр.). Многообразие патогенетических механизмов, лежащих в основе НДЗ, обусловливает возможность сочетанного применения нейропротективных соединений, действующих последовательно на разных этапах патологического процесса. Накоплено достаточно много экспериментальных данных, позволяющих считать, что СПС могут быть основой для создания лекарственных препаратов нового поколения для лечения нейродегенеративных заболеваний.
Mathematical modelling of elastic vibrations arising from four-body impact interaction
This paper presents a mathematical model of elastic vibrations arising from shock interaction in a four-body system. The resulting model has two applications: the study of linear elastic interaction and the study of nonlinear elastic interaction. The linear elastic body model is presented in analytical form. In the transition to nonlinear interaction, it is difficult to represent the model in analytical approximation. The application of numerical algorithms has made it possible to obtain solution of a nonlinear problem with a specified accuracy sufficient for the simulated process. The model is intended for the description of the behavior of the device for measuring the modulus of elasticity of soil by the stamp method. An algorithm is developed to obtain the displacement and acceleration of the falling load and the loading die. Under laboratory conditions, an experiment with a test rig capable of measuring the acceleration of a loading die during shock-elastic interaction with the falling load is conducted. The measuring part is a three-axis accelerometer sensor connected to a four-channel analog-digital converter, which transmits the data to a mobile device with the developed specialized software. The sampling frequency of the measuring system is 12 kHz for each of the four channels. Polyurethane was used as a nonlinear element of the system, the approximate stiffness of which was determined experimentally by measuring deformations under a given load. When comparing the experimental results with the simulation results, the numerical model parameters were optimized by an algorithm based on gradient descent, which was based on maximizing the correlation coefficient between the theoretical and experimental data
Two-dimensional clusters in digital metallographic images of steel’s ferritic-pearlitic microstructure
Study of neutron-rich isotopes near N=152 shell closure using Timepix type detectors integrated into the mass separator MASHA
The MASHA facility [1–3] was developed as a high precision mass-spectrometer for heavy and super heavy elements with masses up to 450 a.m.u. It uses ISOL (Isotope Separation On-Line) method. Its unique properties opens great prospective for the investigation of neutron-rich nuclei produced in multinucleon transfer reactions. Mainly nuclei near the neutron N = 126 and N = 152 shell closures are of great interest. This region of nuclei is not so far thoroughly enough investigated while its research has direct relation to the synthesis of super heavy elements. As is known the island of stability close to super heavy elements (Z = 112–118) exists due to the shell effects in nuclei. More detailed investigation of these shell effects can greatly help in the synthesis of next super heavy elements. Heavy neutron rich radon isotopes were produced in the multinucleon transfer reaction 40Ar + 232Th at Flerov Laboratory of Nuclear Reactions, Dubna. Radon isotopes with given masses were detected using two types of detectors: a multi-strip well-type detector (made in Canberra) and a position-sensitive quantum counting hybrid pixel detector of the Timepix type [4]. The latter detector has an array of 256x256 square pixels each with a pitch size of 55 um for the full sensitive area 14x14mm2. Radon isotopes implanted into the detector emit then alpha and beta particles until they reach the stable or long-lived isotopes at the end of their decay chains. The positions of radon isotopes, the tracks, times and energies of the beta particles were measured and analyzed. New software for the particle recognition and data analysis of the results obtained from the experiment was developed and used. It has been proven that MASHA + Timepix setup is a powerful instrument for investigation of neutron-rich isotopes far from stability limits
The using of thermal analysis methods for study of pore formation in the system resol phenol-formaldehyde resin – Ethylene glycol – p-toluenesulfonyl chloride
Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique: a test case of the Mars Express Phobos fly-by
The closest ever fly-by of the Martian moon Phobos, performed by the European Space Agency's Mars Express spacecraft, gives a unique opportunity to sharpen and test the Planetary Radio Interferometry and Doppler Experiments (PRIDE) technique in the interest of studying planet-satellite systems. Aims. The aim of this work is to demonstrate a technique of providing high precision positional and Doppler measurements of planetary spacecraft using the Mars Express spacecraft. The technique will be used in the framework of Planetary Radio Interferometry and Doppler Experiments in various planetary missions, in particular in fly-by mode. Methods. We advanced a novel approach to spacecraft data processing using the techniques of Doppler and phase-referenced very long baseline interferometry spacecraft tracking. Results. We achieved, on average, mHz precision (30 mu m/s at a 10 s integration time) for radial three-way Doppler estimates and sub-nanoradian precision for lateral position measurements, which in a linear measure (at a distance of 1.4 AU) corresponds to similar to 50 m