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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.
361

Safety limit estimation for cataract induced by ultraviolet radiation /

Dong, Xiuqin, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.
362

Prevention of complications in pediatric cataract surgery /

Kugelberg, Maria, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
363

Posterior capsule opacification and postoperative endophthalmitis following cataract surgery : predictive and protective factors /

Wejde, Gisela, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 6 uppsatser.
364

The role of kynurenine and UV light in lens protein modification

Parker, Nicole Renee. January 2005 (has links)
Thesis (Ph.D.)--University of Wollongong, 2005. / Typescript. EMBARGOED - This thesis is subject to a 12 month embargo (07/03/06 to 07/03/07) and may only be viewed and copied with the permission of the author. For further information please Contact the Archivist. Includes bibliographical references: leaf 236-266.
365

Cataract from ultraviolet radiation in the mouse /

Meyer, Linda Maren. January 2005 (has links)
Licentiatavhandling (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 3 uppsatser.
366

Regulation of the redox-mediated platelet-derived growth factor (PDGF) mitogenic function in human lens epithelial cells

Wang, Yin. January 2008 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Mar. 31, 2009). PDF text: x, 186 p. : ill. ; 8 Mb. UMI publication number: AAT 3331460. Includes bibliographical references. Also available in microfilm and microfiche formats.
367

Interactive tutorials in the marketing of digital cameras : how tutorials benefit consumers & retailers /

Eckert, Andrew C. January 2008 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (leaf 30).
368

Superoxide dismutase 1 and cataract

Olofsson, Eva, January 2009 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 4 uppsatser.
369

Exploration of Ray Mapping Methodology in Freeform Optics Design for Non-Imaging Applications

Ma, Donglin January 2015 (has links)
This dissertation investigates various design metrologies on designing freeform surfaces for LED illumination applications. The major goal of this dissertation is to study designing freeform optical surfaces to redistribute the radiance (which can be simplified as intensity distribution for point source) of LED sources for various applications. Nowadays many applications, such as road lighting systems, automotive headlights, projection displays and medical illuminators, require an accurate control of the intensity distribution. Freeform optical lens is commonly used in illumination system because there are more freedoms in controlling the ray direction. Design methods for systems with rotational and translational symmetry were well discussed in the 1930's. However, designing freeform optical lenses or reflectors required to illuminate targets without such symmetries have been proved to be much more challenging. For the simplest case when the source is an ideal point source, the determination of the freeform surface in a rigorous manner usually leads to the tedious Monge-Ampère second order nonlinear partial different equation, which cannot be solved with standard numerical integration techniques. Instead of solving the differential equation, ray mapping is an easier and more efficient method in controlling one or more freeform surfaces for prescribed irradiance patterns. In this dissertation, we investigate the ray mapping metrologies in different coordinate systems to meet the integrability condition for generating smooth and continuous freeform surfaces. To improve the illumination efficiency and uniformity, we propose a composite ray mapping method for designing the total internal reflective (TIR) freeform lens for non-rotational illumination. Another method called "double pole" ray mapping method is also proposed to improve system performance. The ray mapping designs developed for the point source do not work well for extended sources, we have investigated different design methodologies including optimization method, deconvolution method and feedback modification method to design freeform optical surfaces for extended sources.
370

A Multi-Resolution Foveated Laparoscope

Qin, Yi January 2015 (has links)
Laparoscopic surgery or minimally invasive surgery has great advantages compared with the conventional open surgery, such as reduced pain, shorter recovery time and lower infection rate. It has become a standard clinical procedure for cholecystectomy, appendectomy and splenectomy. The state-of-the-art laparoscopic technologies suffer from several significant limitations, one of which is the tradeoff of the limited instantaneous field of view (FOV) for high spatial resolution versus the wide FOV for situational awareness but with diminished spatial resolution. Standard laparoscopes lack the ability to acquire both wide-angle and high-resolution images simultaneously through a single scope. During the surgery, a trained assistant is required to manipulate the laparoscope. The practice of frequently maneuvering the laparoscope by a trained assistant can lead to poor or awkward ergonomic scenarios. This type of ergonomic conflicts imposes inherent challenges to laparoscopic procedures, and it is further aggravated with the introduction of single port access (SPA) techniques to laparoscopic surgery. SPA uses one combined surgical port for all instruments instead of using multiple ports in the abdominal wall. The grouping of ports raises a number of challenges, including the tunnel vision due to the in-line arrangement of instruments, poor triangulation of instruments, and the instrument collision due to the close proximity to other surgical devices. A multi-resolution foveated laparoscope (MRFL) was proposed to address those limitations of the current laparoscopic surgery. The MRFL is able to simultaneously capture a wide-angle view for situational awareness and a high-resolution zoomed-in view for fine details. The high-resolution view can be scanned and registered anywhere within the wide-angle view, enabled by a 2D optical scanning mechanism. In addition, the high-resolution probe has optical zoom and autofocus capabilities, so that the field coverage can be dynamically varied while keep the same focus distance as the wide-angle probe. Moreover, the MRFL has a large working distance compared with the standard laparoscopes, the wide-angle probe has more than 8x field coverage than a standard laparoscope. On the other hand, the high-resolution probe has 3x spatial resolution than a standard one. These versatile capabilities are anticipated to have significant impacts on the diagnostic, clinical and technical aspects of minimally invasive surgery. In this dissertation, the development of the multi-resolution foveated laparoscope was discussed in detail. Starting from the refinement of the 1st order specifications, system configurations, and initial prototype demonstration, a customized dual-view MRFL system with fixed optical magnifications was developed and demonstrated. After the in-vivo test of the first generation prototype of the MRFL, further improvement was made on the high-resolution probe by adding an optical zoom and auto-focusing capability. The optical design, implementation and experimental validation of the MRFL prototypes were presented and discussed in detail.

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