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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

Transformation of Muscle Architecture at the Fiber Bundle Level to Fit Parametric B-spline Volumes: Extensor carpi radialis brevis and longus

Ravichandiran, Mayoorendra 27 July 2010 (has links)
Most models of the musculoskeletal system incorporate individual or groups of muscles as a series of line segments, assuming all fiber bundles within a muscle have the same length and moment arm, and do not account for architectural differences throughout the muscle volume. The purpose was to develop an algorithm to fit digitized fiber bundle data from one specimen into muscle volume and intramuscular nerve distribution data from seven other specimens of extensor carpi radialis longus (ECRL) and brevis (ECRB). Coherent Point Drift (CPD) algorithm was successfully adapted for this purpose. The intramuscular nerve distribution and fiber bundle architecture was modeled in all the muscle volumes. ECRL was found to have two neuromuscular compartments, superficial and deep, while ECRB was found to have two, three or four, in a proximal to distal direction depending on the number of primary nerve branches.
2

Transformation of Muscle Architecture at the Fiber Bundle Level to Fit Parametric B-spline Volumes: Extensor carpi radialis brevis and longus

Ravichandiran, Mayoorendra 27 July 2010 (has links)
Most models of the musculoskeletal system incorporate individual or groups of muscles as a series of line segments, assuming all fiber bundles within a muscle have the same length and moment arm, and do not account for architectural differences throughout the muscle volume. The purpose was to develop an algorithm to fit digitized fiber bundle data from one specimen into muscle volume and intramuscular nerve distribution data from seven other specimens of extensor carpi radialis longus (ECRL) and brevis (ECRB). Coherent Point Drift (CPD) algorithm was successfully adapted for this purpose. The intramuscular nerve distribution and fiber bundle architecture was modeled in all the muscle volumes. ECRL was found to have two neuromuscular compartments, superficial and deep, while ECRB was found to have two, three or four, in a proximal to distal direction depending on the number of primary nerve branches.
3

Involvement of urinary bladder Connexin43 and the circadian clock in coordination of diurnal micturition rhythm / 膀胱のコネキシン43と概日時計は日内排尿リズムに関与している

Negoro, Hiromitsu 23 July 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第17826号 / 医博第3824号 / 新制||医||999(附属図書館) / 30641 / 京都大学大学院医学研究科医学専攻 / (主査)教授 渡邉 大, 教授 村井 俊哉, 教授 柳田 素子 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
4

Design of Confocal Microendscopy for Fallopian Tube Imaging and Detection of Esophageal Cancer

Wu, Tzu-Yu January 2015 (has links)
This work presents several major developments related to a fluorescence confocal microendoscope technology that can provide instantaneous cellular level images from selected depths of tissue inside the human body. The confocal microendoscope systems discussed employ fiber-optic based imaging catheters coupled to custom built slit-scan confocal microscopes. One major new development involves the design, development, and testing of a new flexible confocal microgastroscope (CMG) system for imaging the esophagus. This new system has the potential to aid in the early detection of esophageal cancer. It consists of a new optical scan unit mounted on an endoscopy cart and a new flexible catheter that can be inserted through the instrument channel of a commercial gastroscope. The CMG system has higher spatial resolution and larger field of view than the previous generation clinical confocal microendoscopes in our lab. In addition, the new CMG system can be operated over a greater wavelength range than its predecessor. Central to the CMG system is the design, construction, and testing of a new distal miniature objective that enables high-quality microendoscopy. The miniature objective, built with all glass spherical surfaces, achieves diffraction-limited performance over a 486 to 1000 nm spectral range. The wide achromatic range of this lens allows the CMG system to be used with a variety of contrast agents including agents in the NIR region. In addition, the new miniature objective can be mounted on existing confocal microendoscopes in our lab such as the ovarian clinical confocal microlaparoscope and our laboratory based experimental system. Finally, a new confocal microlaparoscope with an articulating catheter capable of imaging inside the distal portion of fallopian tubes is presented. This instrument is intended to allow the detection of early stage ovarian cancer originating inside the fallopian tube. The new microlaparoscope is compatible with 5 mm trocars and includes a thin 2.2 mm diameter articulating distal tip consisting of a bare fiber bundle and an automated dye delivery system. The distal tip of this new endoscope can be articulated through simple wrist movements and locked in place at a given angle if desired. The thin distal tip and the ability to control the angle of the tip provide the size and flexibility needed to image inside the curved and delicate structures of the fallopian tube. Preliminary imaging results from the new CMG system, the achromatized miniature objective, and the new articulating confocal microlaparoscope are presented to demonstrate the performance and the potential of each system towards the overall goal of in vivo imaging and disease diagnosis.
5

Integrated Multi-Spectral Fluorescence Confocal Microendoscope and Spectral-Domain Optical Coherence Tomography Imaging System for Tissue Screening

Makhlouf, Houssine January 2011 (has links)
A multi-modality imaging system intended for clinical utilization has been developed. It is constructed around an existing fiber-bundle-based fluorescence confocal microendoscope. Additional imaging modalities have been implemented to expand the capabilities of the system and improve the accuracy of disease diagnosis. A multi-spectral mode of operation is one such modality. It acquires fluorescence images of a biological sample across a spectral range of sensitivity and explores the collected image data at any specified wavelength within that spectral range. Cellular structures can be differentiated according to their spectral properties. The relative distribution and concentration of the different cellular structures can potentially provide useful pathologic information about the imaged tissue. A spectral-domain optical coherence tomography (SDOCT) modality is another imaging technique integrated into the system. It provides a cross-sectional imaging perspective that is comparable to microscopic images obtained from histology slides and complementary to the en face view obtained from the confocal imaging modality. The imaging system uses a parallelized architecture (fiber-optic bundle, line of illumination) to increase the data acquisition speed. A one-dimensional scan is needed to capture 2D images in the confocal modality or a 3D data cube (two spatial dimensions and one spectral dimension) in the multi-spectral mode of operation. No scanning is required to capture a 2D OCT image. The fiber-bundle design is particularly critical for the SDOCT modality as it paves the way to novel fast endoscopic OCT imaging that has a high potential for translation into the clinic. The integrated multi-modality imaging system can readily switch between different imaging modalities, which will make it a powerful diagnostic tool in a clinical environment. It can provide valuable information about the morphology, the spectral and biochemical features, and the macroscopic architecture of tissue. It is believed that fast and accurate disease diagnosis can potentially be made based on all these characteristics.
6

Coincidência de aplicações em fibrados com base circulo e fibra garrafa de Klein. / Coincidence of maps on Klein bottle Fiiber bundles over the Ciircle.

Silva, Weslem Liberato 03 March 2009 (has links)
Sejam K, a garrafa de Klein, e K M S^ um fibrado com base S^ e fibra K. Neste trabalho estudamos o seguinte problema: dadas aplicações f, g : M M que preservam fibra sobre S^, quando o par (f, g) pode ser deformado, por uma homotopia que preserva fibra sobre S^, a um par de aplicações (f^{\'} , g^{\'} ) livre de coincidência? / Let K be the Klein bottle and let K M S be a Klein bottle bundle over S 1 . In this work we study the following question: given a pair of fiber preserving maps over S^ , when can it be deformed by a fiberwise homotopy over S into a pair of coincidence free fiber preserving maps over S^, (f^{\'} , g^{\'} ) ?
7

Deformabilidade sobre S^1 a livre de ponto fixo para auto-aplicações de T-fibrados e Reidemeister sobre S^1 / Deformability over S^1 of self-maps of T-bundles into a fixed point free map and Reidemeister over S^1

Prado, Gustavo de Lima 25 March 2010 (has links)
Classificação das auto-aplicações de fibrados, com fibra toro, que preservam fibra sobre o círculo, com a propriedade de poderem ser deformadas sobre o círculo a uma aplicação livre de ponto fixo. Ainda, investigamos a relação entre o número de Reidemeister sobre o círculo e a propriedade acima / Classification of all fiber-preserving self-maps of torus bundles over the circle by the property of being able to deform them over the circle into a fixed point free map by a fiberwise homotopy over the circle. We also investigate the relationship between Reidemeister number over the circle and the property above
8

The Complete Structure of Linear and Nonlinear Deformations of Frames on a Hilbert Space

Agrawal, Devanshu 01 May 2016 (has links)
A frame is a possibly linearly dependent set of vectors in a Hilbert space that facilitates the decomposition and reconstruction of vectors. A Parseval frame is a frame that acts as its own dual frame. A Gabor frame comprises all translations and phase modulations of an appropriate window function. We show that the space of all frames on a Hilbert space indexed by a common measure space can be fibrated into orbits under the action of invertible linear deformations and that any maximal set of unitarily inequivalent Parseval frames is a complete set of representatives of the orbits. We show that all such frames are connected by transformations that are linear in the larger Hilbert space of square-integrable functions on the indexing space. We apply our results to frames on finite-dimensional Hilbert spaces and to the discretization of the Gabor frame with a band-limited window function.
9

Ultrathin Single and Multi-Channel Fiberscopes for Biomedical Imaging

Kano, Angelique Lynn January 2009 (has links)
Ultrathin fiberscopes typically have an imaging channel and an illumination channeland are available in diameters ranging from 0.5 mm to 2.5 mm. The minimum diam-eter can be reduced by combining the illumination and imaging paths into a singlefiberoptic channel. Constructing a single channel fiberscope requires a technique ofilluminating the tissue, while minimizing the Fresnel reflections and scatter withinthe common illumination and detection channel.A single channel fiberscope should image diffusely reflected light from tissue illu-minated with light filtered for the visible wavelength range (450 - 650 nm). Simplycombining the illumination and collection paths via a beamsplitter results in a lowobject to background signal ratio. The low contrast image is due to a low collectionefficiency of light from the ob ject as well as a high background signal from the Fresnelreflection at the proximal surface of the fiber bundle, where the illumination enters thefiber bundle. The focus of the dissertation is the investigation of methods to reducethe background signal from the proximal surface of the fiber bundle. Three systemswere tested. The first system uses a coherent fiber bundle with an AR-coating on theproximal face. The second system incorporates crossed polarizers into the light path.In addition, a technique was developed, whereby a portion of the image numericalaperture is devoted to illumination and a portion to image signal detection. Thistechnique is called numerical aperture sharing (NA sharing).This dissertation presents the design, construction, testing, and comparison ofthe three single channel fiberscopes. In addition, preliminary results of a study aimedat the usefulness of broadband diffuse reflectance imaging for the identification andtracking of disease progression in mouse esophagus are presented.
10

Deformabilidade sobre S^1 a livre de ponto fixo para auto-aplicações de T-fibrados e Reidemeister sobre S^1 / Deformability over S^1 of self-maps of T-bundles into a fixed point free map and Reidemeister over S^1

Gustavo de Lima Prado 25 March 2010 (has links)
Classificação das auto-aplicações de fibrados, com fibra toro, que preservam fibra sobre o círculo, com a propriedade de poderem ser deformadas sobre o círculo a uma aplicação livre de ponto fixo. Ainda, investigamos a relação entre o número de Reidemeister sobre o círculo e a propriedade acima / Classification of all fiber-preserving self-maps of torus bundles over the circle by the property of being able to deform them over the circle into a fixed point free map by a fiberwise homotopy over the circle. We also investigate the relationship between Reidemeister number over the circle and the property above

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