• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 357
  • 187
  • 98
  • 67
  • 47
  • 18
  • 16
  • 11
  • 9
  • 9
  • 9
  • 9
  • 9
  • 9
  • 7
  • Tagged with
  • 993
  • 300
  • 157
  • 154
  • 123
  • 101
  • 98
  • 91
  • 77
  • 76
  • 75
  • 70
  • 64
  • 55
  • 50
  • 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.
221

Optical Fibre-Based Hydrophone and Critical Ignition in Detonation Cells

Cheevers, Kevin 06 October 2021 (has links)
This thesis is composed of two distinct parts. The first part of this work addresses the problem of critical ignition behind a decaying shock wave in the context of cellular detonations. Low-pressure (4.1 kPa) shock tube experiments were performed in a thin rectangular channel using the highly-unstable mixture of CH4 + 2O2 and the weakly-unstable mixture of 2H2 + O2 + 7Ar, with Schlieren visualization of the flow field. The dynamics of the lead shock in a detonation cell was reconstructed from measurements of the lead shock position and curvature. The post-shock state and the expansion rate along the path of a Lagrangian particle crossing the lead shock at any given point in the cell cycle were evaluated with the shock jump and shock change equations. The chemical evolution behind the shock was then integrated using a detailed chemistry model. Quenching of the post-shock reaction zone was found within the first half of the detonation cell for both mixtures, with quenching occurring earlier in the highly unstable mixture. Simplified models derived from 1-step and 2-step chemistry models very accurately predict the quenching of the post-shock reactions and the evolution of the ignition delay through the cell. The second part describes the assembly and characterization of a fibre-optic probe hydrophone (FOPH) for the measurement of shock waves associated with blast-induced neuro-trauma. Compared to traditional polyvinylidene difluoride (PVDF) hydrophones, the assembled FOPH has a higher bandwidth and smaller active diameter, which are comparable to the characteristic time and thickness of shock waves associated with blast-induced neuro-trauma. However, the sensitivity of FOPHs are substantially lower than traditional hydrophones. We assemble a FOPH and provide detailed calculations and measurements of its sensitivity (0.66 mV/MPa) , noise floor, and spatial resolution. The 150 MHz bandwidth, limited by the photodetector, is sufficient for resolving shock waves with over-pressures of up to 174 kPa with 3 measurement points. Experimental measurements of the system noise gives a floor of 260 Pa/√Hz . A detailed noise analysis finds that the system is limited by photodetector noise (215 Pa/√Hz), which is 4x the fundamental shot noise limit, closely followed by a laser noise of 150 Pa/√Hz. We conclude that the system noise floor is insufficient for resolved measurements of the post-shock pressure in the range associated with blast-induced neuro-trauma. From our noise analysis, we quantify the sensitivity enhancement required for resolving this regime, and we conclude that sensitivity-enhancing fibre-coatings could provide a sufficient increase in sensitivity.
222

Self-Formation of Optic Cups and Storable Stratified Neural Retina from Human ESCs / ヒトES細胞からの眼杯および保存可能な多層網膜組織の自己組織化

Nakano, Tokushige 23 January 2014 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第12800号 / 論医博第2072号 / 新制||医||1001(附属図書館) / 80844 / (主査)教授 髙橋 淳, 教授 吉村 長久, 教授 江藤 浩之 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
223

Brain Mechanisms Underlying Integration of Optic Flow and Vestibular Cues to Self-motion / オプティカルフローと自己運動知覚に関する前庭情報の統合の神経基盤

Uesaki, Maiko 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(文学) / 甲第20828号 / 文博第758号 / 新制||文||655(附属図書館) / 京都大学大学院文学研究科行動文化学専攻 / (主査)教授 蘆田 宏, 教授 板倉 昭二, 教授 Anderson James Russell, 准教授 ALTMANN Christian / 学位規則第4条第1項該当 / Doctor of Letters / Kyoto University / DFAM
224

Electrophysiology of Optic Nerves in Methylglyoxal Treated Mice

Vaughan, Parker Andrew 07 June 2020 (has links)
No description available.
225

Isolation of microglia from goldfish brain

Houalla, Tarek. January 2001 (has links)
No description available.
226

Temporal changes in the ability of degenerating pathways to be penetrated by regenerating axons in the goldfish

Paré, Michel, 1958- January 1983 (has links)
No description available.
227

Studies of early neural regeneration in the visual system of the goldfish

Lowenger, Elizabeth. January 1986 (has links)
No description available.
228

The Effects of Perception-Action Coupling on Compromised Human Locomotion: A Proposed Research Program

De Melo, Kristen January 2021 (has links)
There is considerable evidence suggesting an innate linkage between the human perceptual and motor systems, which evolve together and assist one another in the production and coordination of movement. A major contributor to this relationship is optic flow, providing movement variables such as navigation, obstacle avoidance, and depth perception. The absence of optic flow leads to the decoupling of perception and action, which has been shown to contribute to decrements in human movement (i.e., negatively impacted locomotion and posture, and slower adaptation to gait perturbations). Despite the importance of maintaining this linkage, optic flow manipulations are often found to be underrepresented in locomotion literature when specifically related to rehabilitation training (i.e., treadmills). This may be a contributor to the lengthy and exhaustive treatment plans. The literature has shown instances where reintroducing optic flow into training protocols has shown larger gait improvements in shorter times than typical ambulation protocols, however, the strength of the perception-action linkage in adulthood is still not well understood and its impact not yet fully explored. Therefore, the current research program aims to fill this gap by evaluating how the reintroduction of optic flow into atypical gait training protocols in both healthy and gait-compromised individuals may provide evidence that could be used to enhance rehabilitative outcomes. This series of conceptually related experiments explores outcome enhancements through neuromuscular level changes (Study One), the recalibration process of perception-action given newly acquired physical constraints (Study Two), and on larger scale gait cycle performances in a rehabilitation setting (Study Three). It is hypothesized that perception- action coupling will lead to increases in neuromuscular elicitation in the absence of voluntary movement (Study One), assist the recalibration process to improve measures of spatial awareness and atypical gait parameters (Study Two), and finally, improve rehabilitative outcomes in a spinal cord injury (SCI) ambulation protocol, both objectively (i.e., gait parameters, dynamic balance, SCI measures) and subjectively (i.e., questionnaires) (Study Three). / Thesis / Master of Science (MSc)
229

Telencephalic Terminals in the Major Retinal Synaptic Lamina of the Goldfish Optic Tectum

Airhart, Mark J., Kriebel, Richard M. 17 June 1985 (has links)
Light and electron microscopic degeneration studies were used to examine the telencephalotectal pathway in goldfish. Both techniques showed that each telencephalic lobe sent bilateral projections to several tectal laminae. Degenerating synaptic terminals and fibers were observed in the major retinal projection lamina as well as in other tectal laminae. The terminals contained round to oval synaptic vesicles, asymmetric synapses and contacted relatively small postsynaptic profiles.
230

Layered Illumination : Changeable expressions in woven textile using optic fibers.

Haapalainen, Norea January 2022 (has links)
This work sets out to explore changeability in woven expressions using optic fibers in an interior context for home environment. The primary motive is to investigate how optic fibers can change the expression of a woven textile through its color and placement in the structure. The work was conducted with a trial and error-method by sketching, weaving samples, etching the optic fibers, and exploring how the fibers changed the expression and properties of the woven textile. Experiments with displaying the textiles in the intended environment were conducted in order to experience the effect of color and expression changeability. With the optic fibers the expressions repurpose weave structures and patterns, connecting them to the craft of weaving. The result is three double woven textiles with two stages each, activated and unactivated. In the activated state, the optic fibers brings new expressions through color and pattern from a white textile, which is the unactivated stage.

Page generated in 0.0279 seconds