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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.
101

Induced responses of Gnaphalium vira-vira and Gnaphalium luteo-album to UV-B radiation

Burgueno, Pedro Osvaldo Cuadra January 1996 (has links)
No description available.
102

Mechanisms underlying UVR-induced melanogenesis

Carsberg, Catherine Jane January 1994 (has links)
No description available.
103

Gene expression studied by in situ hybridization in cutaneous neoplasia and following insult to skin

Smith, Martin Damian January 1994 (has links)
No description available.
104

Assay of DNA photoproducts

Bowden, Gemma M. January 1995 (has links)
No description available.
105

Hyperspectral imaging using ultraviolet light

Porter, Michael A. 12 1900 (has links)
The LINEATE IMAGING NEAR ULTRAVIOLET SPECTROMETER (LINUS) instrument has been used to remotely detect and measure sulfur dioxide (SO2). The sensor was calibrated in the lab, with curves of growth created for the 0.29 0.31 æ - spectral range of the LINUS sensor. Field observations were made of a coal burning plant in St. Johnâ s, Arizona at a range of 537 m. The Salt River Coronado plant stacks were emitting on average about 100 ppm and 200 ppm from the left and right stacks respectively. Analysis of the LINUS data matched those values within a few percent. Possible uses for this technology include remote verification of industry emissions and detection of unreported SO2 sources.
106

The pathophysiology of UVA-light induced hyperalgesia

Themistocleus, Andreas Constantinos 08 September 2009 (has links)
D.Phil. Faculty of Health Sciences, University of the Witwatersrand, 2009 / In this thesis I describe the development of an animal model of sustained hyperalgesia induced by exposure to ultraviolet (UV) A light to the rat’s tail, and the role of the Cfibre barrage and peripheral afferent fibre sensitization in this model of hyperalgesia. Exposure of rats’ tails to UVA-light caused hyperalgesia to a noxious thermal challenge, immersion of the rats’ tails into 49°C water, and a noxious mechanical challenge, application of a static force of 3.9N by a bar algometer onto the rats’ tails. The hyperalgesia to the thermal challenge lasted eight days and hyperalgesia to the mechanical challenge continued for up to 16 days. Despite the sustained hyperalgesia, rats exposed to UVA-light showed no overt signs of morbidity as they gained weight normally and were mobile throughout the study. Histological examination of rat tail tissue showed mild, chronic inflammation in rats exposed to UVA-light and in rats that had their tails covered with a protective layer of aluminium foil during UVA-light exposure. This inflammation was therefore not responsible for the behavioural hyperalgesia. To investigate the role of C-fibre barrage in the development of hyperalgesia after UVA-light exposure, I pre-emptively blocked C-fibre activation during UVA-light exposure with the local anaesthetic bupivacaine. Injection of bupivacaine (1ml of 0.5%), into the base of the tail prevented the development of thermal hyperalgesia to tail immersion in 49°C water. However, it did not prevent the development of hyperalgesia to a noxious punctate challenge. Thus the sustained mechanical hyperalgesia did not depend on the activation of the C-fibre barrage, but thermal hyperalgesia did depend on the activation of a C-fibre barrage during the conditioning event of UVA-light exposure. Lastly, in rats anaesthetised with enflurane, I examined the responses of coccygeal primary afferent fibres to noxious thermal and mechanical stimulation after UVA-light exposure of their receptive fields on the tail. I investigated only pure nociceptive afferents and ignored those afferents that responded to challenges in the noxious and non-noxious ranges. The peak firing rates and areas under the curve of post-challenge histograms, a measure of neuronal firing over time, of Ad- and C-fibres were increased when noxious blunt and punctate challenges were applied to the rats’ tails after UVA-light exposure, showing that Ad- and C-fibres that encode for noxious mechanical challenges were sensitized. The peak firing rate of C-fibres that were responsive to noxious thermal challenges were not increased after UVA-light exposure. Therefore, thermal hyperalgesia was probably mediated by sensitization of central nervous system neurones. In summary, I developed a model of sustained mechanical and thermal hyperalgesia caused by UVA-light exposure of the rat tail. The thermal hyperalgesia was initiated by the C-fibre barrage, while mechanical hyperalgesia did not depend on the C-fibre barrage and peripheral afferent sensitization of Ad- and C-fibres could account for the mechanical hyperalgesia.
107

Improvement of Ultraviolet Protection of Polyester Nonwoven -A Study of Volvos Parcel Shelves

LUNDIN, ELIN, HÄGG TURESSON, MIKAELA January 2014 (has links)
The parcel shelf in a car is one of the things that are most exposed to ultraviolet light and heat. The sunlight causes ultraviolet radiation and excessive heat to this area. This can cause the material to degrade, fade or drift in colour. The parcel shelf production is today divided between three producers. This requires a good contact and cooperation between the different actors. As the automobile industry is a very complex industry, high demand is required of everyone involved. The goal of this study was to find improvements that could lead to a better ultraviolet and heat protection. Volvo Cars provided material and the experiments were held on their test facility. The tests were conducted based on the Volvo Cars requirements and methods. A Weather-Ometer is used to simulate the ultraviolet light and heat, the same way a parcel shelf is exposed to outdoors. Chemical analyses are used to determine whether there is any difference in the material when it is aged in a Weather-Ometer or not. The parcel shelf is made of needle punched, dispersed dyed polyester. The results showed that the present parcel shelf material does indeed show a colour shift after ageing. The authors present a number of suggestions to improve the material's characteristics. For example, Volvo could consider using an acrylic non-woven instead of polyester. Dyes that withstand ultraviolet radiation better can also be chosen and a variety of ultraviolet absorbers can be added. 2-(2-hydroxy-5-carboxy-phenyl)-2H-benzotriazole, Tinuvin P, 327 [2-(2-hydroxy-5-methyl-phenyl) 2H-benzotriazole, 2-(3,5-butyl-6-hydroxy)-2H-2-chloro-benzotriazole respectively] and 2,4-dihydroxy-benzophenone are example of absorbers that can be added to make the ultraviolet resistance better. / Program: Textilingenjörsutbildningen
108

Deep ultraviolet solid-state laser development /

Dutton, David A. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 71-72). Also available on the World Wide Web.
109

The ultraviolet absorption spectra of lignin and related compounds

Glading, Ralph E. (Ralph Edmond) 01 January 1940 (has links)
No description available.
110

The action of ultraviolet light on lignin

Forman, Loren Verne January 1940 (has links)
No description available.

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