Typescript (photocopy) / xii, 285 leaves [16] leaves of plates (some col.) : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1982

Thesis (Ph.D.) -- University of Adelaide, Dept. of Physics, 1982. / Typescript (photocopy).

At late times during the infection of human KB cells with Adenovirus type 2 (Ad 2), the ultraviolet (uv) sensitivity of transcription was assayed by DNA-RNA hybridization across the length of the genome. Assuming that the majority of the nuclear transcripts at this time of infection are read from the rightward transcribing DNA strand, the resulting plot of the surviving fraction of viral transcription vs. genome position indicates two transcription units are responsible for the transcription from selected DNA restriction fragments of the genome were also obtained. The uv inactivation cross sections generated from such curves identified a long, uv sensitive transcript originating from the major late promoter at approximately 17 map units, and a shorter, less uv sensitive from approximately 63 map units on the genome. The shorter transcription unit accounts for about one third to a half of the viral nuclear RNA synthesized from the right hand 30 to 40% of the genome. The majority of the late viral nuclear transcripts, however, originated at approximately 17 map units and terminated at around 60-70 map units. Similar experiments examining the uv sensitivity of cytoplasmic poly A RNA production at various sites across the length of the genome are consistent with two rightward transcribing transcription units expressed during late Ad 2 infection. The transcriptional organization of late Ad 2 gene expression was also approached through uv transcription unit mapping experiments by examining the uv sensitivities of the synthesis of late Ad 2 proteins for which the approximate gene locations are known. The effect of uv on Ad 2 nuclear transcription was also reflected at the polypeptide level indicating two transcription units are responsible for the synthesis of mRNA coding for late viral proteins. The differential radiosensitivities of late protein synthesis confirmed the relative gene positions on the Ad 2 genome. / Thesis / Master of Science (MS)

No description available.

Exposure to UV radiation is known to result in the development of skin cancer and the use of protectants m the form of topically applied sunscreens is becoming widespread. The compounds used within sunscreen formulations are subject to stringent tests and must be approved for use by such bodies as COLIPA (EC), or the FDA (U.S.). Despite these testing procedures the photochemical and photophysical properties of many of the active ingredients are poorly understood and not well documented. This study presents the results of detailed photophysical investigations of two sunscreen agents. Menthyl anthranilate is currently approved for use m commercially available formulations by the FDA, and N-acetyl-menthyl anthranilate has been synthesised as an analogue of N-acetyl-homomenthyl anthranilate, a compound approved for use by COLIPA until 1989. This work has highlighted some disturbing properties of these compounds. Following absorption of light both compounds fluoresce m UV-A region. Population of the triplet state also occurs to a significant extent, producing long lived species which are readily quenched by oxygen generating singlet oxygen, a potentially damaging species that has been linked to DNA damage. Furthermore, the triplet state energy of N-acetyl-menthyl anthranilate has been shown to be -315 kJmol(^-1)"', high enough to sensitise the formation of thymine dimers m the skin, another potential source of DNA damage. A thorough understanding of the behaviour of sunscreen formulations m contact with skin is vital. In vivo studies are made difficult due to restrictions in the sampling methods for currently used spectroscopic techniques such as UV and fluorescence. This work demonstrates the use of infixed spectroscopy, utilising an ATR probe and a flat ATR crystal, to analyse sunscreen formulations present on skin at normal usage levels. The technique has been used successfully to identify the individual active components within the formulations, probe the water-resistance properties and monitor changes that occur within the formulations following irradiation. A relationship between the IR absorbance values and Sun Protection Factor (SPF) values of any given formulation has been demonstrated and this has been used to test the water resistance claims of the manufacturers.

[no abstract submitted] / Science, Faculty of / Zoology, Department of / Graduate

With the increasing interest in the indoor air environment over the last 30 years has come the need for control devices that can improve the quality of air that people breath. To answer this need, many devices have been developed and are currently in use. This thesis utilizes Ultra-violet light to eradicate the bacteria. A portable unit was constructed that contains the light bulb and fan. Two different trials were conducted: Controlled Laboratory trials and Fish Culture Room Trials. The Controlled Laboratory Experiments were conducted in order to test the effect that the Ultra-violet unit had on known cultures of bacteria while the Fish Culture Room Trials were conducted to test the chambers affect on a real indoor situation. The Ultra-violet unit was effective in eradicating the known cultures that were tested, and was less effective in the real indoor setting. As the density of bacteria increased, the effectiveness of the chamber increased, for the real indoor setting. The contact time of the chamber could be adjusted to improve effectiveness. More testing is necessary to fully evaluate the potential of a portable Ultra-violet disinfection chamber. / Master of Science

No description available.

No description available.

No description available.