Модель минно-взрывной травмы

Цель. Создание доступной модели минно-взрывной травмы различной степени тяжести у крыс. Материалы и методы. Взрывное повреждение мягких тканей бедра крыс моделировали с помощью строительно-монтажного пистолета (СМП) и специально разработанной стойки, которая обеспечивала фиксацию СМП во время выстрела. Для имитации повреждения от поражающих элементов в стволе СМП размещали стальные осколки. Результаты. Макроскопическая оценка повреждений показала, что они имеют признаки, характерные для поражения мягких тканей ударной волной, струей пламени, поражающими элементами. Показана возможность варьировать степень поражения тканей за счет мощности порохового заряда, отсутствия или наличия поражающих элементов. Выводы. Предложенная модель воспроизводит минно-взрывную травму и может быть использована в любой научно-исследовательской лаборатории, занимающейся вопросами экспериментальной медицины

Теплофизические свойства и структура отложений на поверхностях нагрева энергетического оборудования

The paper shows influence of heating surface material, design peculiarities, operational conditions of heat exchangers and water-chemical regime on chemical and structural composition of deposits, their heat conduction and porosity.Показано влияние материала поверхности нагрева, конструктивных особенностей, условий эксплуатации теплообменных устройств и водно-химического режима на химический и структурный состав отложений, их теплопроводность и пористость

The Role of Interdiffusion and Spatial Confinement in the Formation of Resonant Raman Spectra of Ge/Si(100) Heterostructures with Quantum-Dot Arrays

The phonon modes of self-assembled Ge/Si quantum dots grown by molecular-beam epitaxy in an apparatus integrated with a chamber of the scanning tunneling microscope into a single high-vacuum system are investigated using Raman spectroscopy. It is revealed that the Ge-Ge and Si-Ge vibrational modes are considerably enhanced upon excitation of excitons between the valence band $\Lambda_3$ and the conduction band $\Lambda_1$ (the E1 and E1 + $\Delta_1$ transitions). This makes it possible to observe the Raman spectrum of very small amounts of germanium, such as one layer of quantum dots with a germanium layer thickness of 10 \r{A}. The enhancement of these modes suggests a strong electron-phonon interaction of the vibrational modes with the E1 and E1 + $\Delta_1$ excitons in the quantum dot. It is demonstrated that the frequency of the Ge-Ge mode decreases by 10 cm^-1 with a decrease in the thickness of the Ge layer from 10 to 6 \r{A} due to the spatial-confinement effect. The optimum thickness of the Ge layer, for which the size dispersion of quantum dots is minimum, is determined.Comment: 14 pages, 9 figure

Specific means of communication of people with hearing impairment: origins and prospects of use

В статье рассматриваются проблемы использования специфических средств коммуникации в образовании лиц с нарушением слуха на разных этапах развития сурдопедагогики.To design a new Master's degree education program, the article deals with the issues of application of specific communication means in the education of persons with hearing impairment at different stages of development of surdopedagogy laying stress on the importance of their correct usage in the practice of the modern school for children with hearing impairment and explores the tendencies of the market of education services

Right Isomerism of the Brain in Inversus Viscerum Mutant Mice

Left-right (L-R) asymmetry is a fundamental feature of higher-order neural function. However, the molecular basis of brain asymmetry remains unclear. We recently reported L-R asymmetry of hippocampal circuitry caused by differential allocation of N-methyl-D-aspartate receptor (NMDAR) subunit GluRε2 (NR2B) in hippocampal synapses. Using electrophysiology and immunocytochemistry, here we analyzed the hippocampal circuitry of the inversus viscerum (iv) mouse that has a randomized laterality of internal organs. The iv mouse hippocampus lacks L-R asymmetry, it exhibits right isomerism in the synaptic distribution of the ε2 subunit, irrespective of the laterality of visceral organs. This independent right isomerism of the hippocampus is the first evidence that a distinct mechanism downstream of the iv mutation generates brain asymmetry

ДЕВИТАЛИЗИРОВАННЫЕ СОСУДИСТЫЕ ПРОТЕЗЫ: ИССЛЕДОВАНИЕ IN VIVO

Porcine intrathoracic arteries were devitalized by application of low temperatures and electron beam irradiati- on. The resulted connective tissues vascular scaffolds could be used as the prosthesis of small diameter arteries (≤6 mm). Biocompatibility, immunogenicity degree and thrombogenicity were estimated in the study. Results of electron microscopy are presented. Described treatment reduces an immunogenicity of xenoarteries, their ade- quate functioning during 6 months was shown by means of experimental surgeries. Для девитализации внутренних грудных артерий свиней использовали низкие температуры и облучение потоком электронов. Полученные соединительнотканные сосудистые скаффолды в данном исследовании были использованы в качестве протезов артерий малого диаметра (≤6 мм). В работе изучали биосовме- стимость, степень иммуногенности, тромбогенность девитализированных артерий. Приведены результа- ты электронной микроскопии. Показано снижение иммуногенности девитализированных ксеноартерий. Экспериментальные операции продемонстрировали их адекватное функционирование в течение 6 мес.

Kinetics of ATP release following compression injury of a peripheral nerve trunk

Compression and/or contusion of a peripheral nerve trunk can result in painful sensations. It is possible that release of ATP into the extracellular space may contribute to this symptom. In the present study, we used real-time measurements of ATP-induced bioluminescence together with electrophysiological recordings of compound action potentials to follow changes in the extracellular ATP concentration of isolated rat spinal roots exposed to mechanical stimuli. Nerve compression for about 8 s resulted in an immediate release of ATP into the extracellular space and in a decrease in the amplitude of compound action potentials. On average, a rise in ATP to 60 nM was observed when nerve compression blocked 50% of the myelinated axons. After the compression, the extracellular concentration of ATP returned to the resting level within a few minutes. The importance of ecto-nucleotidases for the recovery period was determined by exposure of isolated spinal roots to high concentrations of ATP and by use of inhibitors of ecto-nucleotidases. It was observed that spinal roots have a high capacity for ATP hydrolysis which is only partially blocked by βγ-methylene ATP and ARL 67156. In conclusion, acute nerve compression produces an increase in the extracellular concentration of ATP and of its metabolites which may be sufficient for activation of purinergic P2 and/or P1 receptors on axons of nociceptive afferent neurons

Absorption of Terahertz Radiation in Ge/Si(001) Heterostructures with Quantum Dots

The terahertz spectra of the dynamic conductivity and radiation absorption coefficient in germanium-silicon heterostructures with arrays of Ge hut clusters (quantum dots) have been measured for the first time in the frequency range of 0.3-1.2 THz at room temperature. It has been found that the effective dynamic conductivity and effective radiation absorption coefficient in the heterostructure due to the presence of germanium quantum dots in it are much larger than the respective quantities of both the bulk Ge single crystal and Ge/Si(001) without arrays of quantum dots. The possible microscopic mechanisms of the detected increase in the absorption in arrays of quantum dots have been discussed.Comment: 9 pages, 4 figures; typos correcte

Colocalized Structural and Functional Changes in the Cortex of Patients with Trigeminal Neuropathic Pain

Background: Recent data suggests that in chronic pain there are changes in gray matter consistent with decreased brain volume, indicating that the disease process may produce morphological changes in the brains of those affected. However, no study has evaluated cortical thickness in relation to specific functional changes in evoked pain. In this study we sought to investigate structural (gray matter thickness) and functional (blood oxygenation dependent level – BOLD) changes in cortical regions of precisely matched patients with chronic trigeminal neuropathic pain (TNP) affecting the right maxillary (V2) division of the trigeminal nerve. The model has a number of advantages including the evaluation of specific changes that can be mapped to known somatotopic anatomy. Methodology/Principal Findings: Cortical regions were chosen based on sensory (Somatosensory cortex (SI and SII), motor (MI) and posterior insula), or emotional (DLPFC, Frontal, Anterior Insula, Cingulate) processing of pain. Both structural and functional (to brush-induced allodynia) scans were obtained and averaged from two different imaging sessions separated by 2–6 months in all patients. Age and gender-matched healthy controls were also scanned twice for cortical thickness measurement. Changes in cortical thickness of TNP patients were frequently colocalized and correlated with functional allodynic activations, and included both cortical thickening and thinning in sensorimotor regions, and predominantly thinning in emotional regions. Conclusions: Overall, such patterns of cortical thickness suggest a dynamic functionally-driven plasticity of the brain. These structural changes, which correlated with the pain duration, age-at-onset, pain intensity and cortical activity, may be specific targets for evaluating therapeutic interventions