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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Efectos de una tarea de condicionamiento por evitación activa sobre los eventos fásicos del sueño Rem en rata

Buller Peralta, Ingrid January 2014 (has links)
Magíster en ciencias biológicas y médicas / El sueño REM puede dividirse en dos clases de actividad. El sueño REM tónico estaría caracterizado por actividad hipocampal sostenida en banda theta y atonía muscular, mientras que la actividad fásica corresponde a episodios breves de eventos tales como trenes de actividad theta de alta frecuencia, movimientos oculares rápidos, mioclonías musculares, incremento de la frecuencia cardiaca y respiratoria, ondas ponto-genículo-occipitales (en gatos y humanos) y, en ratas particularmente, ondas pontinas y movimiento de la musculatura de vibrisas. Si bien, como estadío global, se ha asociado al sueño REM con la consolidación de memorias emocionales, evidencias del incremento de las ondas pontinas luego de un condicionamiento por evitación activa apuntan a una mayor relevancia de los eventos fásicos para este tipo de aprendizaje. Así, se propuso estudiar los efectos de la adquisición de una tarea de evitación activa sobre los movimientos fásicos de vibrisas, contracciones de musculatura nucal y eventos fásicos de theta, mediante de la cuantificación de cambios en su densidad por minuto de sueño REM en un grupo de ratas. Los resultados demostraron incrementos significativos de los eventos fásicos musculares (movimientos de vibrisas y contracciones de nuca) en el grupo que adquirió el aprendizaje de evitación activa, mientras que se observó un aumento significativo de los eventos fásicos de theta en el grupo control diseñado para medir estrés por exposición al estímulo aversivo. Ambos incrementos ocurrieron de forma sostenida luego de la exposición a sus respectivos protocolos, e independientes de las variaciones en la distribución temporal del sueño REM. Los hallazgos obtenidos permiten sugerir que: 1) los eventos fásicos musculares del sueño REM serían indicadores de consolidación de una memoria emocional cuyo aprendizaje implica control de un estresor, y 2) los eventos fásicos de theta darían cuenta de la imposibilidad de manejar un evento aversivo mediante la conducta y, en último término, indicarían el nivel de estrés sufrido por el sujeto. En conjunto, los resultados apuntan a una manifestación diferencial de los eventos fásicos del sueño REM durante el procesamiento de la experiencia emocional de la vigilia previa, de modo que el nivel de estrés sufrido y la capacidad de ejercer control sobre posibles amenazas activaría mecanismos de generadores antagónicos. / According to the tonic-phasic model, rapid eye movement (REM) sleep can be categorized in two types of activity. Tonic REM sleep, featured by the classical muscular atonia and sustained hippocampal theta activity, can be briefly interrupted by phasic events such as high frequency theta bursts, rapid-eye movements, muscular twitches or limbs myoclonia, increased respiratory and cardiac activity, ponto-geniculo-occipital waves, and pontine waves and whiskers movements in rats. Even when, as a whole, REM sleep has been associated to emotional memories consolidation, growing evidence on increased P-wave activity after active avoidance conditioning suggests greater importance of phasic events for this kind of emotional learning. Thus, this investigation aimed to study the effects of the active avoidance task acquisition over phasic whisker movements, nuchal twitches and theta phasic events, measuring their density per minute of REM sleep in rats. The results demonstrate significant increases of phasic muscle events (whisker and nuchal twitches) in the active avoidance learning group, whereas phasic theta events were significantly augmented in the group designed for the aversive stimulus stress control. Both increments were sustained through the sleep phase recordings after exposure to their respective protocols, and showed independence from the REM sleep`s temporal distribution shifts. These findings suggest that: 1) REM sleep`s phasic muscle events could be physiological markers of an emotional memory consolidation which involves control of an aversive stimulus, and 2) Theta phasic events could indicate the inability of behavioral control over an aversive stimulus and, ultimately, the stress level of the subject. Altogether, the results appoint to a differential phasic event expression during REM sleep processing of previous emotional situations, so that the stress level and the experienced control level over menaces activate antagonists neural generating mechanisms.
2

Mitwirkendes Verschulden bei Eigentumsansprüchen /

Köhling, Franz Schulze. January 1935 (has links)
Thesis (doctoral)--Universität Marburg.
3

The detection of REM and Wake sleep stages by using EOG signals

Wang, Yen-shi 18 July 2008 (has links)
To detect REM and wake stages in sleep, this study generates feature variables from the correlation of two-channel EOG signals and the amplitude of LEOG signal. By using the VQ method to quantize these signals into different codewords and by calculating the number of appearances of these codewords, we are able to establish a feature vector for every epoch of the recorded EOG signals. Via a three-stage process, the personalized classification accuracy for REM and wake sleep stages are about 95% and 86%, respectively. By combining these personalized classifiers to perform REM and wake stages detection for other unseen individuals, the classification accuracy for REM and wake sleep stages, the classification accuracy become 85% and 92%. However, the sensitivity for the wake stage detection is merely 52%.
4

Da obrigação propter rem. / Propter rem obligation

Bunazar, Mauricio Baptistella 22 March 2013 (has links)
O objetivo desta dissertação é analisar o instituto da obrigação propter rem à luz do direito positivo brasileiro. Com isso, pretende-se fornecer uma descrição dogmaticamente coerente do instituto. Para atingir esse objetivo, foram analisadas categorias jurídicas que, em sede de obrigação propter rem, são controvertidas, entre as quais, destacam-se a renúncia e o abandono liberatório / The aim of this dissertation is to analyze the institute of the propter rem obligation through the light of the Brazilian positive Law. With that, it intends to provide a dogmatically consistent description of the institute. To achieve this goal, there were analyzed legal categories that, in place of propter rem obligation, are issued; including, the waiver and the discharging relinquishment that are stood out.
5

Da obrigação propter rem. / Propter rem obligation

Mauricio Baptistella Bunazar 22 March 2013 (has links)
O objetivo desta dissertação é analisar o instituto da obrigação propter rem à luz do direito positivo brasileiro. Com isso, pretende-se fornecer uma descrição dogmaticamente coerente do instituto. Para atingir esse objetivo, foram analisadas categorias jurídicas que, em sede de obrigação propter rem, são controvertidas, entre as quais, destacam-se a renúncia e o abandono liberatório / The aim of this dissertation is to analyze the institute of the propter rem obligation through the light of the Brazilian positive Law. With that, it intends to provide a dogmatically consistent description of the institute. To achieve this goal, there were analyzed legal categories that, in place of propter rem obligation, are issued; including, the waiver and the discharging relinquishment that are stood out.
6

Sleep in a naturalistic environment and the influence of the calendar week

Sedgwick, Philip Martin January 2000 (has links)
No description available.
7

Qualitative and quantitative SEM margin analysis of Ormocer restorations in molars and premolars - 4 year long observation / Qualitative und quantitative REM Randanalyse von Ormocer Zahnrestaurationen in Molaren und Premolaren - 4 jährige Observation

Veryha, Katarzyna January 2011 (has links) (PDF)
The most important aim of restorative therapy in dentistry is to achieve a restoration that remains dense from bacteria and this way from tooth pulp irritation as well. Patients on the other hand appreciate and expect additionally good aesthetics. This way the decision which material the practitioner should chose very often still causes dilemmas. The aim of this 4 year long study was to evaluate the Admira filling material, that belongs to ormocer group and its future in the area of restorative dentistry. SEM analysis of fillings margins followed on epoxy resin casts (achieved from impressions taken at each of the control appointments) and showed that after four years of clinical observation more than 90 percent of the restoratives margins remained perfectly adapted. Due to technical reasons the examination followed only in the enamel area and as a result this study is not answering the question of margin quality within the dentin. / Celem współczesnych materiałów odtwórczych w stomatologii zachowawczej jest na pierwszym miejscu zapewnienie doskonałego połączenia ich z tkankami twardymi zęba, zaròwno szkliwem jak i zębiną. Z drugiej jednak strony pojawiają się wysokie oczekiwania pacjentów jeśli chodzi o estetykę wypełnień. Wszystko to prowadzi nierzadko do dylematów lekarza stomatologa i trudności w wyborze odpowiedniego materiału do odbudowy uszkodzonych tkanek zęba. Celem tej pracy była ocena materiału do wypełnień Admira, należącego do grupy ormocerów i skuteczności jego zastosowania. Analiza adaptacji brzeżnej wypełnień została przeprowadzona na modelach z żywicy epoksydowej, uzyskanych z wycisków pobieranych podczas każdej z wizyt kontrolnych w skaningowym mikroskopie elektronowym. Wykazała ona, iż po okresie fizjologicznego obciążenia wypełnień w jamie ustnej w przeciągu 4 lat ponad 90 procent z nich nadal charakteryzowało się doskonałą adaptacją brzeżną. Z przyczyn technicznych zbadana została tylko jakość połączenia w obrębie szkliwa i w związku z tym praca ta nie udziela odpowiedzi na pytanie o jakość połączenia w obrębie zębiny, które jak wiadomo jest słabsze.
8

Pharmacogenetic Inhibition of the Subcoeruleus Region Influences REM Sleep and Cataplexy in Narcoleptic Mice

Sanghera, Karan Paul 27 November 2013 (has links)
Introduction: Cataplexy - the sudden involuntary loss of skeletal muscle tone – is a defining feature of narcolepsy. The current study aimed to determine if cataplexy is influenced by direct manipulation of REM sleep circuitry. We did this by pharmacogenetically inhibiting the REM sleep center, subcoeruleus (Sub-C). Methods: Inhibitory DREADD (hM4D-Gi) was bilaterally targeted to the Sub-C in hypocretin knockout mice (n=7). Intraperitoneal administration of clozapine-n-oxide was used to inhibit Sub-C cells expressing hM4D-Gi. Electrophysiological and behavioral criteria were used to characterize cataplexy and REM sleep. Results: Sub-C inhibition increased REM sleep and cataplexy amounts (p<0.05). Sub-C inhibition increased time spent in cataplexy amounts by increasing the number of cataplexy attacks (p<0.05). This intervention triggered increases in basal muscle tone during REM sleep, but had negligible effects on muscle tone during cataplexy (p>0.05). Conclusion: Pharmacogenetic manipulation of the Sub-C suggest that REM sleep and cataplexy are mediate by similar neural mechanism.
9

Pharmacogenetic Inhibition of the Subcoeruleus Region Influences REM Sleep and Cataplexy in Narcoleptic Mice

Sanghera, Karan Paul 27 November 2013 (has links)
Introduction: Cataplexy - the sudden involuntary loss of skeletal muscle tone – is a defining feature of narcolepsy. The current study aimed to determine if cataplexy is influenced by direct manipulation of REM sleep circuitry. We did this by pharmacogenetically inhibiting the REM sleep center, subcoeruleus (Sub-C). Methods: Inhibitory DREADD (hM4D-Gi) was bilaterally targeted to the Sub-C in hypocretin knockout mice (n=7). Intraperitoneal administration of clozapine-n-oxide was used to inhibit Sub-C cells expressing hM4D-Gi. Electrophysiological and behavioral criteria were used to characterize cataplexy and REM sleep. Results: Sub-C inhibition increased REM sleep and cataplexy amounts (p<0.05). Sub-C inhibition increased time spent in cataplexy amounts by increasing the number of cataplexy attacks (p<0.05). This intervention triggered increases in basal muscle tone during REM sleep, but had negligible effects on muscle tone during cataplexy (p>0.05). Conclusion: Pharmacogenetic manipulation of the Sub-C suggest that REM sleep and cataplexy are mediate by similar neural mechanism.
10

Vindicatio incertae partis ihre Bedeutung für die Erkenntnis der geschichtlichen Entwicklung des klassischen dinglichen Verfahrens.

Cromme, Ingrid, January 1971 (has links)
Inaug.-Diss.--Heidelberg. / Vita. Bibliography: p. i-x.

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