Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvi, 157 p.; also includes graphics (some col.) Includes bibliographical references (p. 146-157).

Thesis (Ph. D.)--University of Chicago, Dept. of Biochemistry and Molecular Biology, December 2002. / Includes bibliographical references. Also available on the Internet.

Thèse (Ph. D.)--Université Laval, 2003. / Bibliogr.: f. 293-345. Publ. aussi en version électronique.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2006. / On t.p. "F̳u̳" is superscript. Includes bibliographical references (leaves 131-161). Also available in electronic version.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 86-98).

No description available.

Signal transduction via the phosphoinositide (PI) second messenger system has key roles in the development and plasticity of the neocortex. The present study localized PI responses to individual cortical layers in slices of developing rat somatosensory cortex. The acetylcholine agonist carbachol and the glutamate agonist trans-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD) were used to stimulate PI turnover. The PI responses were compared to the distribution of the corresponding PI-linked receptors in order to investigate the regional ontogeny of PI coupling to receptors in relation to neural development. The method for assessing PI turnover was modified from Hwang et al. (1990). This method images the PI response autoradiographically through the localizaton of [3H]cytidine that has been incorporated into the membrane-bound intermediate, cytidine diphosphate diacylglycerol. In each age group (postnatal days 4-30), carbachol resulted in more overall labeling than ACPD. For both agonists, the response peaked on postnatal day 10 (P10) and was lowest in the oldest age group. The laminar distribution of the carbachol PI response from P4-P16 corresponded fairly well with the laminar distribution of [3H]quinuclidinyl benzilate binding (Fuchs, 1995). However, in the subplate layer the carbachol response was strong while receptor binding was minimal. The carbachol response decreased after postnatal day 10, while the overall levels of receptor binding continued to increase. From P5 - P14, PI-linked metabotropic glutamate receptors are most concentrated in layer IV (Blue et al., 1997), whereas only on P6 was there a correspondingly high ACPD-initiated PI response in this layer. Unlike receptors, the PI response was strong in upper V (P4 - P12) and within layers II/III (P8 - P16). From P4 - P21, the subplate showed relatively high PI labeling compared to receptor binding. The several differences between the distribution of PI response and receptors suggest spatiotemporal heterogeneity of receptor coupling to second messenger systems.

Au cours de ces dernières années, les progrès technologiques dans le domaine dumicro-usinage sur silicium ont permis le développement de Micro/Nano SystèmesÉlectro Mécaniques (M/NEMS) pour réaliser des capteurs ou des actionneurs.Dans le domaine des NEMS, dont les dimensions sont par définition submicroniques,les propriétés obtenues permettent de viser des applications en analyse biochimiqueou biomédicale. Il a été démontré que ces nano capteurs de masse (ou de force)atteignent des résolutions de l’ordre du zeptogramme (10−21 g) ou du picoNewtonce qui permet d’envisager des diagnostics précoces de certains cancers.Tous ces systèmes utilisent `a l’heure actuelle des moyens d’actionnement et dedétection électriques: de nombreuses équipes ont néanmoins démontré que la photoniqueactionne et détecte des mouvements de très faibles amplitudes, de l’ordredu femtomètre. Cette technologie hybride, circuit photonique associé au M/NEMS,offre potentiellement un gain de performance important par rapport aux moyens detransduction électromécanique.L’objectif de la thèse est le développement de la transduction optomécanique afinde détecter le déplacement de résonateurs NEMS. Un simple modèle analytique estproposé avec le support d’un simulation numérique. Les performances de transductionoptique sont comparées aux caractéristiques de la transduction électrique. Lacomparaison se base sur des critères objectifs (sensibilité, bruit, encombrement) puisde proposer des structures optomécaniques originales. Un banc de caractérisationoptique et mécanique est développé pour la caractérisation des échantillons dans unenvironnement contrôlé. Des mesures sur des composants fabriqués permettent demieux appréhender les contraintes de dimensionnement et, de façon plus général, latransduction optomécanique appliqué aux dispositifs NEMS. / During several last years, technological advances in the field of silicon micromachininghave initiated the industrial growth of Micro/Nano Electro Mechanical Systems(M/NEMS) for fabricating sensors or actuators.In the field of NEMS with sub-micron sizes, the properties allow for targeting applicationsin biomedical or biochemical analyses. It has been demonstrated that thesenano mass (or force) sensors achieve resolutions of the order of zeptogram (10−21 g)or picoNewton, hence allowing early diagnosis of certain cancers.Transduction schemes of these systems are currently based on electrical principles:many teams have nevertheless shown that photonics operates and detects tiny displacementin the order of femtometer. This hybrid technology, photonic circuitassociated with M/NEMS, potentially offers a significant improvement compared toelectrical transduction.The purpose of the thesis consists of developing the optomechanical transductionfor NEMS resonators displacement. A simple analytical model is presented togetherwith a numerical simulation. The performance of optical detection is compared toelectrical detection features. The comparison is based on objective criteria (sensitivity,noise, crowding) for designing original optomechanical structures. A dedicatedbench has been developed for the optical and mechanical characterizations of thesamples placed in a controlled environment. Measurements on fabricated devicesallow a better understanding of the design constrains and, more in general, of theoptomechanical detection applied to NEMS.i

published_or_final_version / Zoology / Doctoral / Doctor of Philosophy