22 research outputs found

    Effect of particle size on the surface properties and morphology of ground flax

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    Flax fibers were ground with a ball-mill and four fractions with different size ranges were collected by sieving. These were tested for water sorption, degree of polymerization (DP), copper number, hydroxyl number and analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and inverse gas chromatography (IGC). Significant differences were found between the properties of the flax fiber and those of the ground versions, including fragmentation of fibers, increase of water sorption, copper number, hydroxyl number and surface O/C ratio, and decrease of DP, crystallite size and dispersive component of surface energy (gammasd). Some parameters depended on the particle size: O/C ratio and hydroxyl number had local maxima at 315-630 μm, while gammasd increased steadily with the decrease of particle size. These relationships were explained by fiber disintegration, destruction of waxy surface layer, exposure of cellulosic components, increase of surface area and crystalline imperfections

    Intracranial neuronal ensemble recordings and analysis in epilepsy

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    Pathological neuronal firing was demonstrated 50 years ago as the hallmark of epileptically transformed cortex with the use of implanted microelectrodes. Since then, microelectrodes remained only experimental tools in humans to detect unitary neuronal activity to reveal physiological and pathological brain functions. This recording technique has evolved substantially in the past few decades; however, based on recent human data implying their usefulness as diagnostic tools, we expect a substantial increase in the development of microelectrodes in the near future. Here, we review the technological background and history of microelectrode array development for human examinations in epilepsy, including discussions on of wire-based and microelectrode arrays fabricated using micro-electro-mechanical system (MEMS) techniques and novel future techniques to record neuronal ensemble. We give an overview of clinical and surgical considerations, and try to provide a list of probes on the market with their availability for human recording. Then finally, we briefly review the literature on modulation of single neuron for the treatment of epilepsy, and highlight the current topics under examination that can be background for the future development

    Magyar Gyógypedagógia 19 (1931) 01-04

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    A Magyar Gyógypedagógiai Társaság folyóirata 19. évfolyam, 1-4. szám, Budapest, 1931. Havi folyóirat a fogyatékosok (siketnémák, vakok, szellemileg gyengék, beszédhibások, idegesek, epileptikusok és nyomorékok) ügyeinek tárgyalására. 1939-től beolvadt a Magyar gyógypedagógiai tanárok közlönyébe

    Region-Selective Control of the Thalamic Reticular Nucleus via Cortical Layer 5 Pyramidal Cells

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    Corticothalamic pathways, responsible for the top-down control of the thalamus, have a canonical organization such that every cortical region sends output from both layer 6 (L6) and layer 5 (L5) to the thalamus. Here we demonstrate a qualitative, region-specific difference in the organization of mouse corticothalamic pathways. Specifically, L5 pyramidal cells of the frontal cortex, but not other cortical regions, establish monosynaptic connections with the inhibitory thalamic reticular nucleus (TRN). The frontal L5–TRN pathway parallels the L6–TRN projection but has distinct morphological and physiological features. The exact spike output of the L5-contacted TRN cells correlated with the level of cortical synchrony. Optogenetic perturbation of the L5–TRN connection disrupted the tight link between cortical and TRN activity. L5-driven TRN cells innervated thalamic nuclei involved in the control of frontal cortex activity. Our data show that frontal cortex functions require a highly specialized cortical control over intrathalamic inhibitory processes

    Sárospataki turizmusfejlesztési tanulmányok 2022.

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    Zemplénben 1997-ben, a Magyar Turizmus Rt. K+F Igazgatósága – a főbb térségi aktorokkal egyeztetett és elfogadtatott - turizmusfejlesztési terv készítésére vonatkozó megbízásával kezdődött meg az a politikai és szakmai együttgondolkodás, mely 2 évtized múltán elvezetett a tokaji részen 72 települést magába foglaló Tokaj és Nyíregyháza turisztikai térség kijelöléséhez és a Tokaj-Zemplén Térség Fejlesztési Program elindításához. A Zemplén Régió Fejlesztése Sorozat 2011-es indulása óta ezen hatodik tanulmánykötet ismételten a turizmus közösségi fejlesztésének folyamatait, eredményeit tekinti át, idén a sárospataki, már megvalósult, vagy a megvalósulás, tervezés stádiumában lévő turisztikai fejlesztésekre fókuszálva

    In vivo validation of the electronic depth control probes.

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    In this article, we evaluated the electrophysiological performance of a novel, high-complexity silicon probe array. This brain-implantable probe implements a dynamically reconfigurable voltage-recording device, coordinating large numbers of electronically switchable recording sites, referred to as electronic depth control (EDC). Our results show the potential of the EDC devices to record good-quality local field potentials, and single- and multiple-unit activities in cortical regions during pharmacologically induced cortical slow wave activity in an animal model
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