96 research outputs found

    Interrelation of cerebral vessels reactivity and state of central afferent inductive structures at chronic mercury intoxication

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    The following groups were examined under clinical condition: the 1st group (47 persons) - the employees with a long work period working at the Joint-Stock Company "Sayanskchimplast" exposed to mercury compound. The mean age - 49,2 ± 4,4 years old, the mean working period -18,1 ± 5,6 years. The 2nd group (51 persons) consisted of the employees working at the Joint-Stock Company "Usolyechimprom" in Irkutsk Region with the diagnosis of chronic mercury intoxication (CMI), the mean age - 42,7 ± 4,3 years old and the mean time period of exposure to mercury - 12,3 ± 2,7 years. The postcontact period amounted 8,5 ± 2,6 years. The examination data of 26 persons (males) who were not exposed to the harmful production factors were used as the control one. All the persons examined were subjected to the ultrasonic dopplerography of the extracranial vessels and the registration of the somatosensoric induced potentials. This study allowed to assess the state of the cerebral hemodinamics manifested as the autoregulation disorder of the brain bloodflow along the metabolic contour in the employees examined in both groups. It should be noted the presence of the change correlation in the state of the central afferent inductive structures consisting in growing the time period of the central conductive capability, that is, the conductance from the lower sections of the stem up to the brain cortex and the functional change in the metabolic diameter regulation of the cerebral vessels in the patients exposed to the metallic mercury at the production. As compared with the control the more expressed index change of the somatosensoric induced potentials were registered in the subgroup of the patients in the postponed period of chronic mercury intoxication with the revealed regulation disorders of the cerebral vessels. The change were found to correlate with the impulse conductance disorders at the level of the thalamic and cortical structures. The attention should be paid that the change revealed were registered in the group of the patients exposed to the metallic mercury at the production but without the revealed diagnosis of chronic mercury intoxication with allow to consider the presence of the changes in the state of the conductive structures in this group of the patients examined

    EVALUATION OF EFFICIENCY OF BIOLOGICAL FEEDBACK TRAINING IN PATIENTS WITH LOCAL VIBRATION-INDUCED DISEASE

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    The article describes the evaluation of efficiency of the temperature-myographic training in the patients with vibration-induced disease after the local vibration exposure based on the data of the thermometry, the dosed cold sample, the rheography of the upper extremities, the algesimetry, the pallaesthesimetry, the psychological examination to control the changes in the neuropathic pain, the electroneuromyography. It was shown that the training effectively influenced the manifestations of the angiodystonic syndrome as well as to restore the nervous-muscular conducti-vity at the upper and. the lower extremities

    The use of Soluble Products of Wood Oxidative Catalytic Delignification as Binders for Obtaining Fuel Briquettes

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    Методом ИКС изучен функциональный состав растворимых продуктов каталитической делигнификации древесины осины и пихты Н2О2 в среде разбавленной уксусной кислоты. Растворимые продукты имеют высокую долю кислородсодержащих функциональных групп, и их термическая обработка при 160 °С в течение 2 ч дает возможность получать связующее с показателями вязкости, соответствующими промышленным смолам, применяемым для производства древесных плитных материалов. Определены оптимальные технологические параметры получения древесных топливных брикетов с высокой прочностью при использовании растворимых продуктов делигнификации: содержание связующего в пресс-массе 40–50 % мас.; температура прессования 90 °С; давление прессования 13 МПаThe functional composition of soluble products of aspen and fir woods catalytic delignification by H2O2 in a medium of dilute acetic acid was studied by FTIR method. Soluble products have a high content of oxygenated functional groups and their thermal treatment at 160 °C for 2 hours makes it possible to obtain a binding agent with viscosities relevant industrial resins used for the production of wood-panel materials. The optimum technological parameters for obtaining the wood fuel briquettes with high strength characteristics with the use of soluble delignification products were established: the binder content in the press-mass – 40-50 % wt .; pressing temperature – 90 °C; compaction pressure – 13 MP

    OPPORTUNITIES OF USE OF THE BIOFEEDBACK METHOD IN REHABILITATION OF PATIENTS WITH OCCUPATIONAL DISEASES CAUSED BY CHEMICAL AND PHYSICAL FACTORS

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    The article shows the opportunity of use of biomonitoring in patients with exogenous toxic encephalopathy in the remote period of chronic mercury intoxication. (CMI) and with, vibration disease caused by local vibration. The efficiency of the biofeedback method was assessed on the basis of the data of electroencephalography, auditory, visual and somatosensoric generated potentials, electroneuromyography, thermometry, dosed cold test and. rheography. Biofeedback training in people with. CMI caused decrease of total brain changes in EEG, improvement of amplitude indices at of the brain generated potentials, in people with vibration disease it caused decrease of manifestation of angiodistonic syndrome and. restoration of neuromuscular conductivity

    Structure impact in antenna effect of novel upper rim substituted tetra-1,3-diketone calix[4]arenes on Tb(III) green and Yb(III) NIR-luminescence

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    © 2016 Elsevier Ltd.Two novel calix[4]arene macrocyclic ligands functionalized with four 1,3-diketone groups at the upper and hydroxyl (3) or propyloxy-groups (6) at the lower rims were synthesized and characterized using NMR, IR spectroscopy, mass spectrometry, and elemental analysis. UV-vis spectrophotometry and ESI mass spectrometry studies indicate 1:1 complex formation of ligands 3 and 6 with Ln(III) (Ln=Tb, Yb) in alkaline DMF solutions resulted from coordination of Ln(III) with 1,3-diketonate groups. Luminescence study of Ln(III) complexes with 3 and 6 reveals significant difference in antenna effects of their deprotonated forms on both Tb(III)- and Yb(III)-centered luminescence. Comparison of ligand-centered emission for ligands 3 and 6 points to the latter as more efficient antenna for Tb(III) and Yb(III). Different conformational behavior of ligands 3 and 6 in alkaline media is assumed as a reason for the experimentally observed difference in sensitization pathways in Ln(III) complexes with 3 and 6

    The Use of Chemically Modified Hydrolytic Lignins as Binders in the Obtaining of Wood Composites

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    Проведено исследование по возможности использования образцов химически модифицированного щелочной и окислительной обработкой гидролизного лигнина в качестве связующих при получении древесных композитов. Изучен функциональный состав и термостабильность исходного и химически модифицированных образцов гидролизного лигнина. Установлено, что для получения топливных брикетов с высокой плотностью и водостойкостью целесообразно использовать связующее из лигнина, обработанного пероксидом водорода. Для получения древесных плитных материалов с высокой прочностью на изгиб и низким водопоглощением предложено использовать в качестве связующего гидролизный лигнин, обработанный щелочью. Путем экспериментальной и математической оптимизации определены параметры процесса прессования, обеспечивающие получение древесных плитных материалов с высокими физико-механическими характеристиками при использовании в качестве связующего гидролизного лигнина модифицированного NaOHA study on the possibility of using samples of hydrolytic lignin chemically modified by alkaline and oxidative treatment as a binder in the production of wood composites was carried out. The functional composition and thermal stability of samples of initial and hydrolyzed lignin treated with alkali and hydrogen peroxide have been studied. It was found that in order to obtain fuel briquettes with high density and water resistance, it is advisable to use a binder from lignin treated with hydrogen peroxide. To obtain wood-based board materials with high bending strength and low water absorption, it is proposed to use hydrolytic lignin treated with alkali as a binder. By experimental and mathematical optimization, the parameters of the pressing process, which ensure the production of wood-based board materials with high physical and mechanical characteristics using hydrolytic lignin modified with NaOH as a binder, were determine

    High performance magneto-fluorescent nanoparticles assembled from terbium and gadolinium 1,3-diketones

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    © The Author(s) 2017.Polyelectrolyte-coated nanoparticles consisting of terbium and gadolinium complexes with calix[4]arene tetra-diketone ligand were first synthesized. The antenna effect of the ligand on Tb(III) green luminescence and the presence of water molecules in the coordination sphere of Gd(III) bring strong luminescent and magnetic performance to the core-shell nanoparticles. The size and the core-shell morphology of the colloids were studied using transmission electron microscopy and dynamic light scattering. The correlation between photophysical and magnetic properties of the nanoparticles and their core composition was highlighted. The core composition was optimized for the longitudinal relaxivity to be greater than that of the commercial magnetic resonance imaging (MRI) contrast agents together with high level of Tb(III)-centered luminescence. The tuning of both magnetic and luminescent output of nanoparticles is obtained via the simple variation of lanthanide chelates concentrations in the initial synthetic solution. The exposure of the pheochromocytoma 12 (PC 12) tumor cells and periphery human blood lymphocytes to nanoparticles results in negligible effect on cell viability, decreased platelet aggregation and bright coloring, indicating the nanoparticles as promising candidates for dual magneto-fluorescent bioimaging

    Numerical Optimization of the Process of Cellulose Isolation by Peroxide Delignification of Birch Wood in Acetic Acid-Water Medium in the Presence of TiO₂ Catalyst

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    Показана возможность получения качественного целлюлозного продукта путем пероксидной делигнификации древесины березы в среде уксусная кислота – вода в присутствии катализатора TiO2 при температуре 100 °C. Установлено влияние условий делигнификации (концентрации пероксида водорода и уксусной кислоты, гидромодуля) на выход и состав целлюлозных продуктов. Проведена математическая оптимизация процесса с применением полного факторного эксперимента. Найдены оптимальные условия получения из древесины березы целлюлозного продукта с содержанием остаточного лигнина ≤ 1 мас.%: концентрация СН3СООН 23,8 мас.%, концентрация Н2О2 4,9 мас.%, гидромодуль 14,9, температура 100 °C, продолжительность 4 ч. В оптимальных условиях процесса делигнификации выход целлюлозного продукта с содержанием целлюлозы 92,5 мас.% составил 49,9 мас.%The possibility of isolation of high-quality cellulose by peroxide delignification of birch wood in an acetic acid-water medium in the presence of a TiO2 catalyst at a temperature of 100 °C was shown. The influence of the process conditions (concentration of hydrogen peroxide and acetic acid, liquid/wood ratio (LWR)) on the yield and composition of cellulose products was established. Numerical optimization of the process was carried out using a full factorial experiment. The optimal conditions for isolation from birch wood a cellulose product with residual lignin content of ≤ 1 wt.% are: СН3СООН concentration 23.8 wt.%, Н2О2 concentration 4.9 wt.%, LWR14.9, temperature 100 °C, time 4 h. Under these optimal conditions, the yield of a cellulose product with a cellulose content of 92.5 wt.% was 49.9 wt.
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