193 research outputs found
Thermodynamics and kinetics of boundary friction
No full textA deterministic theory describing the behavior of an ultrathin lubricant film between two atomically-smooth solid surfaces is proposed.
For the description of lubricant state the parameter of excess volume arising due to chaotization of solid medium structure in the
course of melting is introduced. Thermodynamic and shear melting are described. Dependences of friction force
on temperature of lubricant, shear velocity of rubbing surfaces, and pressure upon surfaces are analyzed.
Within the framework of a simple tribological model the stick-slip mode of friction, when the lubricant periodically melts and
solidifies, is described. The obtained results are qualitatively compared with the experimental data.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/1808
Дослідження потужності електричної активності утворень мозку за умов пілокарпін-індукованої спонтанної судомної активності = The investigation of brain structures magnitude in conditios of pilocarpine-induced spontaneous activity
No full textKopyova N. V., Lyashenko S. L., Topal M. M. Дослідження потужності електричної активності утворень мозку за умов пілокарпін-індукованої спонтанної судомної активності = The investigation of brain structures magnitude in conditios of pilocarpine-induced spontaneous activity. Journal of Education, Health and Sport. 2015;5(8):159-176. ISSN 2391-8306. DOI 10.5281/zenodo.28046
http://dx.doi.org/10.5281/zenodo.28046
http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%288%29%3A159-176
https://pbn.nauka.gov.pl/works/607585
Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665X. Archives 2011–2014 http://journal.rsw.edu.pl/index.php/JHS/issue/archive
Deklaracja.
Specyfika i zawartość merytoryczna czasopisma nie ulega zmianie.
Zgodnie z informacją MNiSW z dnia 2 czerwca 2014 r., że w roku 2014 nie będzie przeprowadzana ocena czasopism naukowych; czasopismo o zmienionym tytule otrzymuje tyle samo punktów co na wykazie czasopism naukowych z dnia 31 grudnia 2014 r.
The journal has had 5 points in Ministry of Science and Higher Education of Poland parametric evaluation. Part B item 1089. (31.12.2014).
© The Author (s) 2015;
This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland and Radom University in Radom, Poland
Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium,
provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License
(http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited.
This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non commercial
use, distribution and reproduction in any medium, provided the work is properly cited.
The authors declare that there is no conflict of interests regarding the publication of this paper.
Received: 05.06.2015. Revised 15.07.2015. Accepted: 12.08.2015.
УДК 612.017.1:612.8.062;612.821.7+616.853
ДОСЛІДЖЕННЯ ПОТУЖНОСТІ ЕЛЕКТРИЧНОЇ АКТИВНОСТІ УТВОРЕНЬ МОЗКУ ЗА УМОВ ПІЛОКАРПІН-ІНДУКОВАНОЇ СПОНТАННОЇ СУДОМНОЇ АКТИВНОСТІ
THE INVESTIGATION OF BRAIN STRUCTURES MAGNITUDE IN CONDITIOS OF PILOCARPINE-INDUCED SPONTANEOUS ACTIVITY
Н. В. Копйова, С. Л. Ляшенко, *М. М. Топал
N. V. Kopyova, S. L. Lyashenko, *M. M. Topal
Одеський національний медичний університет, Одеса;
*Одеський національний університет ім. І. І. Мечникова, Одеса
Odessa National Medical University, Odessa;
*Odessa I. I. Mechnikov National University, Odessa
Summary
The article deals with the results of the trials devoted to pilocarpine-induced spontaneous seizure activity pathophysiologic mechanisms investigation. With this aim the main factors determining spontaneous seizure onset were studied as well as hippocampus and frontal cortex pathogenetic role was investigated in conditions pilocarpine-induced chronic epileptogenesis. Status epilepticus development and its duration were shown to be the main factors determining pilocarpine-induced spontaneous seizures. Hippocampal hyperactivation was found to precede the spontaneous seizures formation that afterwards followed by the brain frontal cortex f the electrical activity strengthening. These brain structures electrical activity hyperactivation occurs due to a- and d-rhythms.
Key words: pilocarpine, spontaneous seizures, the hippocampus, cerebral cortex, the power of the electrical activity, pathophysiologic mechanisms.
Резюме
В роботі наведені результати досліджень, присвячених з'ясуванню патофізіологічних механізмів спонтанної судомної активності, індукованої введенням пілокарпіну. З цією метою вивчали основні чинники, що визначають розвиток спонтанних судом, а також з'ясовували патогенетичну роль гіпокампу і фронтальної кори в умовах пілокарпін-викликаного хронічного епілептогенезу. Показано, що розвиток епілептичного статусу, а також його тривалість детермінують формування спонтанних пілокарпін-викликаних судомних реакцій. Визначено, що формуванню спонтанних судом передує гіперактивація нейронів гіпокампу, слід за чим посилюється електрична активність фронтальної кори мозку. Посилення електричної активності зазначених утворень мозку відбувається за рахунок a- та d-діапазонів.
Ключові слова: пілокарпін, спонтанні судоми, гіпокамп, кора мозку, потужність електричної активності, патофізіологічні механізми.
Резюме
ИЗУЧЕНИЕ МОЩНОСТИ ЭЛЕКТРИЧЕСКОЙ АКТИВНОСТИ СТРУКТУР МОЗГА В УСЛОВИЯХ ПИЛОКАРПИН-ИНДУЦИРОВАННОЙ СПОНТАННОЙ СУДОРОЖНОЙ АКТИВНОСТИ. В работе приведены результаты исследований, посвященных выяснению патофизиологических механизмов спонтанной судорожной активности, индуцированной введением пилокарпина. С этой целью изучали основные факторы, определяющие развитие спонтанных судорог, а также выясняли патогенетическую роль гиппокампа и фронтальной коры в условиях пилокарпин-вызванного хронического эпилептогенеза. Показано, что развитие эпилептического статуса, а также его продолжительность детерминируют формирование спонтанных пилокарпин-вызванных судорожный реакций. Выяснено, что формированию спонтанных судорог предшествует гиперактивация нейронов гиппокампа, за которой потом следует усиление электрической активности фронтальной коры мозга. Усиление электрической активности отмеченных структур мозга происходит за счет a- и d-диапазонов.
Ключевые слова: пилокарпин, спонтанные судороги, гиппокамп, кора мозга, мощность электрической активности, патофизиологические механизмы.Kopyova N. V., Lyashenko S. L., Topal M. M. Дослідження потужності електричної активності утворень мозку за умов пілокарпін-індукованої спонтанної судомної активності = The investigation of brain structures magnitude in conditios of pilocarpine-induced spontaneous activity. Journal of Education, Health and Sport. 2015;5(8):159-176. ISSN 2391-8306. DOI 10.5281/zenodo.28046
http://dx.doi.org/10.5281/zenodo.28046
http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%288%29%3A159-176
https://pbn.nauka.gov.pl/works/60758
Dioxomolybdenum(VI) and dioxotungsten(VI) complexes supported by an amido ligand
No full textStepwise addition of one equivalent of n-butyllithium and trimethylsilyl chloride to 2-tert-butylmercaptoaniline affords the new ligand 1-(Me(3)SiNH)-2-(t- BuS)C(6)H(4)(LH), that reacts with one equivalent of butyllithium to its lithium salt LLi. Dioxodichloromolybdenum [MoO(2)Cl(2)] and dioxodichlorotungsten dimethoxyethane [WO(2)Cl(2)(dme)] react in tetrahydrofuran solution at low temperature with two equivalents LLi to monomeric dioxomolybdenum(VI) [MoO(2)L(2)] (1) and dioxotungsten(VI) complex [WO(2)L(2)] (2) employing two bidentate amido thioether ligands. The crystallographic determination of the molecular structures of 1 and 2 show evidence for M center dot center dot center dot S contacts. The reaction of [ MoO2Cl2] with LLi in tetrahydrofuran solution at room temperature leads next to 1 to two compounds where silyl group migration from nitrogen to oxygen atoms occurs forming [Mo(= NL')(2)(OSiMe)(2)] (3) and [Mo(= NL')(2)(OSiMe(3))L] (4, L' = N-2-t-BuSC(6)H(4)) as determined by NMR spectroscopy. Compound 4 was isolated in low yield and its molecular structure determined by X-ray crystallography. Higher yields of a bisimido complex can be obtained by the direct reaction of one equivalent of LLi with [Mo(NAr)(2)Cl(2)(dme)] (Ar = 2,6-Me(2)C(6)H(4)) forming [Mo(NAr)(2)LCl] (5)
Oxo-molybdenum and oxo-tungsten complexes of Schiff bases relevant to molybdoenzymes
No full textA series of octahedral dioxomolybdenum(VI) complexes of the type [MoO(2)L(2)] {L = 4-Ar-pent-2-en-ol; L(i-Pr2Ph) with Ar = 2,6-diisopropylphenyl (1); L(Me2Ph) with Ar = 2,6-dimethylphenyl (2), L(MePh) with Ar = 2-methylphenyl (3) and with Ar = phenyl (4)} and dioxotungsten(VI) compounds [WO(2)L(2)] {L(i-Pr2Ph) (5); L(Me2Ph) (6) and L(MePh) (7)} with Schiff bases have been synthesized as models for oxotransferases. Spectroscopic characterization in solution shows with the sterically encumbered ligands L(i-Pr2)Ph and L(Me2Ph) isomerically pure products whereas the ligand with only one substituent in ortho position at the aromatic ring L(MePh) revealed a dynamic mixture of three isomers as confirmed by variable temperature NMR spectroscopy. Single crystal X-ray diffraction analyses of compounds 1, 2 and 4 showed them to be in the N, N-trans conformation consistent with the larger steric demand at nitrogen. Oxygen atom transfer (OAT) properties towards trimethylphosphine were investigated leading to the isolation of two mononuclear molybdenum(IV) compounds [MoO(PMe(3))(L(Me2Ph)) 2] (8) and [MoO(PMe(3))(L(MePh))(2)] (9) as confirmed by spectroscopic and crystallographic means. The kinetics of OAT between complex [MoO(2)(L(Me2Ph))(2)] (2) and PMe3 was investigated by UV/Vis spectroscopy under pseudo-fist-order conditions revealing single-step reactions with Eyring values of Delta H(not equal) = + 60.79 kJ mol(-1) and Delta S(not equal) = -112 J mol(-1) K(-1) and a first-order dependence of phosphine consistent with a slow nucleophilic attack of the phosphine showing the octahedral geometries of this system to be unfavorable for OAT. Compound 1 showed no OAT reactivity towards PMe(3) emphasizing the influence of sterical properties. Furthermore, the reactivity of the reduced compounds [MoO(PMe(3))(L(Me2Ph))(2)] (8) and [MoO(PMe3)(L(MePh))(2)] (9) towards molecular oxygen was investigated leading, in the case of 8, to the substitution of PMe(3) by O(2) under formation of the peroxo compound [MoO(O(2))(L(Me2Ph))(2)] (10). In contrast, the analogous reaction employing 9 led to oxidation forming the dioxo compound [MoO(2)(L(MePh))(2)] (3).Deutsche Forschungsgemeinschaft [MO 963/2
HE-4(PI+/,PI+/P)H-3 AND HE-4(PI+/,PI+/2P2N) REACTIONS INDUCED BY PIONS OF 120, 135 AND 156 MEV
No full text
STUDY OF THE (PI-P H-3), (PI-2P 2N) AND (3PN) REACTIONS INDUCED BY PIONS ON HE-4 AT 156 MEV
No full textComment on friction between a viscoelastic body and a rigid surface with random self-affine roughness
No full textS.189401111Nr.1
Mechanics of adhesive contacts: experiment and theory
No full textThis article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in AIP Conference Proceedings 2167, 020201 (2019) and may be found at https://doi.org/10.1063/1.5132068.Adhesive contacts between steel indenters and a layer of soft transparent rubber have been studied experimentally and numerically. Experiments were carried out using a setup allowing for slow exact positioning of the indenter in both normal and tangential direction and observing the contact area with a camera placed under the rubber layer. Indentation of flat-ended cylindrical punches showed that Boundary Element simulations very accurately describe experimental results. Changing velocity allowed determining the importance of viscoelastic effects on the adhesive contact
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