Base teórica A deficiência da Vitamina D é um problema mundial, e têm sido associada com inúmeras doenças. Este hormônio pode ser obtido através da alimentação e através da produção na pele pela exposição à radiação ultravioleta B (R-UVB), sendo que a principal fonte é a exposição aos R-UVB. Objetivo Nossos objetivos foram avaliar a prevalência de deficiência da vitamina D de acordo com a estação do ano e seus fatores associados em adultos jovens e saudáveis, na cidade de Porto Alegre, RS, Brasil. Métodos Policiais militares de Porto Alegre, foram convidados a participar do estudo, amostras de sangue foram coletadas no primeiro dia de cada estação, refletindo desta forma a estação que antecedeu a coleta, para dosagem de 25(OH)D3, e PTH plasmáticos, cálcio total, creatinina e albumina no soro foram determinadas no outono. A UV-R foi mensurada a partir da radiação solar por meio de um radiômetro, calculando-se as doses diárias para eritema (D-Ery) e para resposta fotobiológica para síntese da vitamina D na pele humana (D-VitD). Resultados Nossos resultados mostraram uma variação sazonal de 25(OH)D3 (P = 0.000) nos indivíduos estudados, sendo fortemente influenciada pela média da R-UV nos 30 e 45 dias que antecederam as coletas, demonstrando o importante papel da R-UV na produção da vitamina D. A prevalência de 25(OH)D3 abaixo de 20ng/mL variou com as estações (p=0.000), tendo sido nula ou baixa no final do verão e primavera, no entanto, essa prevalência aumentou no final do outono (22%) e inverno (8.7%). Já 6 a prevalência de 25(OH)D3 < 30ng/mL foi alta em todas as estações do ano: inverno (70%), primavera (68%), verão (44%) e especialmente no outono(88%). O único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de UV-R no período que antecedeu a coleta. Conclusão A prevalência de deficiência de vitamina variou de acordo com a estação, em adultos jovens do sexo masculino, na região sul do Brasil, e o único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de R-UV no período que antecedeu a coleta. Palavras chave: Vitamina D, Deficiência de Vitamina D, Radiação ultravioleta, Radiação ultravioleta B. / Background Vitamin D deficiency is a worldwide problem, and has been associated with various diseases. This steroid can be obtained by food intake or by skin production, when exposed to UVB-R. Objective Our aims were to evaluate the prevalence of vitamin D deficiency according to the season and its associated factors in young adults, in Porto Alegre, RS, Brazil. Methods Young men were invited to participate, blood samples were collected on the first day of each season for 25(OH)D3 measurement, and PTH (parathyroid hormone) in plasma, total calcium, creatinine, and albumin in serum were determined in the autumn. UV-R was measured from solar radiation by means of a radiometer, calculating daily doses for erythema (D-Ery) and for photobiological response to vitamin D synthesis in human skin (D-VitD). Results Our results have shown a seasonal variation of 25(OH) D3(P=0.000) in young and healthy men, living in a semitropical region, who were strongly influenced by the mean UV-R in the 30 and 45 days previous, demonstrating the important role of UVR- induced skin production of vitamin D. The prevalence of 25(OH)D3 below 20ng/mL varied with the seasons (p=0.000), having been nil or low in late summer and spring. However, this prevalence increased in late autumn (22%) and winter (8.7%). The prevalence of 25(OH)D3<30ng/mL was high in all seasons of the year: winter (70%), spring (68%), summer (44%) and especially in autumn (88%). Conclusions 8 The prevalence of vitamin deficiency varied according to the season, in young and healthy male adults, in Southern Brazil, and the only factor independently associated with 25(OH)D3 levels was the amount of UV-R in the period prior to collection.

Base teórica A deficiência da Vitamina D é um problema mundial, e têm sido associada com inúmeras doenças. Este hormônio pode ser obtido através da alimentação e através da produção na pele pela exposição à radiação ultravioleta B (R-UVB), sendo que a principal fonte é a exposição aos R-UVB. Objetivo Nossos objetivos foram avaliar a prevalência de deficiência da vitamina D de acordo com a estação do ano e seus fatores associados em adultos jovens e saudáveis, na cidade de Porto Alegre, RS, Brasil. Métodos Policiais militares de Porto Alegre, foram convidados a participar do estudo, amostras de sangue foram coletadas no primeiro dia de cada estação, refletindo desta forma a estação que antecedeu a coleta, para dosagem de 25(OH)D3, e PTH plasmáticos, cálcio total, creatinina e albumina no soro foram determinadas no outono. A UV-R foi mensurada a partir da radiação solar por meio de um radiômetro, calculando-se as doses diárias para eritema (D-Ery) e para resposta fotobiológica para síntese da vitamina D na pele humana (D-VitD). Resultados Nossos resultados mostraram uma variação sazonal de 25(OH)D3 (P = 0.000) nos indivíduos estudados, sendo fortemente influenciada pela média da R-UV nos 30 e 45 dias que antecederam as coletas, demonstrando o importante papel da R-UV na produção da vitamina D. A prevalência de 25(OH)D3 abaixo de 20ng/mL variou com as estações (p=0.000), tendo sido nula ou baixa no final do verão e primavera, no entanto, essa prevalência aumentou no final do outono (22%) e inverno (8.7%). Já 6 a prevalência de 25(OH)D3 < 30ng/mL foi alta em todas as estações do ano: inverno (70%), primavera (68%), verão (44%) e especialmente no outono(88%). O único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de UV-R no período que antecedeu a coleta. Conclusão A prevalência de deficiência de vitamina variou de acordo com a estação, em adultos jovens do sexo masculino, na região sul do Brasil, e o único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de R-UV no período que antecedeu a coleta. Palavras chave: Vitamina D, Deficiência de Vitamina D, Radiação ultravioleta, Radiação ultravioleta B. / Background Vitamin D deficiency is a worldwide problem, and has been associated with various diseases. This steroid can be obtained by food intake or by skin production, when exposed to UVB-R. Objective Our aims were to evaluate the prevalence of vitamin D deficiency according to the season and its associated factors in young adults, in Porto Alegre, RS, Brazil. Methods Young men were invited to participate, blood samples were collected on the first day of each season for 25(OH)D3 measurement, and PTH (parathyroid hormone) in plasma, total calcium, creatinine, and albumin in serum were determined in the autumn. UV-R was measured from solar radiation by means of a radiometer, calculating daily doses for erythema (D-Ery) and for photobiological response to vitamin D synthesis in human skin (D-VitD). Results Our results have shown a seasonal variation of 25(OH) D3(P=0.000) in young and healthy men, living in a semitropical region, who were strongly influenced by the mean UV-R in the 30 and 45 days previous, demonstrating the important role of UVR- induced skin production of vitamin D. The prevalence of 25(OH)D3 below 20ng/mL varied with the seasons (p=0.000), having been nil or low in late summer and spring. However, this prevalence increased in late autumn (22%) and winter (8.7%). The prevalence of 25(OH)D3<30ng/mL was high in all seasons of the year: winter (70%), spring (68%), summer (44%) and especially in autumn (88%). Conclusions 8 The prevalence of vitamin deficiency varied according to the season, in young and healthy male adults, in Southern Brazil, and the only factor independently associated with 25(OH)D3 levels was the amount of UV-R in the period prior to collection.

Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-09-19T14:46:51Z No. of bitstreams: 2 Tese - Rangel Magalhães Luzin - 2018.pdf: 3753425 bytes, checksum: 3ac739156d95f6ef2de370e5c5ce093c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-20T11:32:29Z (GMT) No. of bitstreams: 2 Tese - Rangel Magalhães Luzin - 2018.pdf: 3753425 bytes, checksum: 3ac739156d95f6ef2de370e5c5ce093c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-20T11:32:29Z (GMT). No. of bitstreams: 2 Tese - Rangel Magalhães Luzin - 2018.pdf: 3753425 bytes, checksum: 3ac739156d95f6ef2de370e5c5ce093c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-08-29 / It is known that sun exposure is one of the factors that contribute greatly to the appearance of skin cancer. Cancer cases have arisen annually on the planet and many of these cases have direct correlation with sun exposure. Knowing that both UVA and UVB radiation are harmful to health when the person is overexposed, the need arises for the use of devices to protect the skin and one of these ways and already recognized by the scientific community is through the prophylactic use of protectors solar power. Thus, this work proposes the synthesis, structural characterization, thermal stability verification, molar absorptivity calculation and in vitro UVB protection factor (PFUVB) calculated by the spectrophotometric method described by Mansur of new compounds derived from structures analogous to natural products. The structural planning was based on triazine derivatives (they are already commercially used with relative efficiency) and the use of chalcones, which are structures that besides having double bonds and conjugated aromatic structures that favor the absorption of the ultraviolet radiation, are studied compounds for various purposes and present in various plants, thus constituting a natural structure. In the planning, the choice of such structures was also due to the synthesis of compounds of high molar mass (above 900 daltons), contributing to safe structures, with low toxicity probability, low skin permeation and in compliance with the demands of the current legislation. The data obtained in the work reinforce the success of the same, where we had for the prototypes synthesized, molar absorptions superior to commercial filters. Establishing a​​research with the use of chalcones in safe and efficient sunscreens. / É sabido que a exposição solar é um dos fatores de grande contribuição para o surgimento do câncer. Casos de câncer tem surgido anualmente no planeta e muitos desses casos tem direta correlação com a exposição solar. Sabendo que tanto a radiação UVA quanto a UVB são nocivas à saúde quando o indivíduo é exposto em demasia, surge a necessidade do uso de artifícios para a proteção da pele e uma dessas maneiras e já reconhecida pelo meio científico é através do uso profilático de protetores solares. Assim este trabalho se propôs a síntese, caracterização estrutural, verificação de estabilidade térmica, cálculo de absortividade molar e fator de proteção solar UVB (FPUVB) in vitro calculado pelo método espectrofotométrico descrito por Mansur de novos compostos derivados de estruturas análogas a produtos naturais. O planejamento estrutural foi baseado nos derivados triazínicos (pois já são de uso comercial com relativa eficiência) e o uso de chalconas, que são estruturas que além de possuir duplas ligações e estruturas aromáticas conjugadas que favorecem a absorção da radiação ultravioleta, são compostos bastante estudados para diversos fins e presente em vários vegetais, constituindo assim uma estrutura natural. No planejamento, a escolha de tais estruturas se deu também pela síntese de compostos de alta massa molar (acima de 900 Daltons), contribuindo para estruturas seguras, com probabilidade de baixa toxicidade, baixa permeação cutânea e atendendo aos reclames das legislações vigentes. Os dados obtidos no trabalho reforçam o sucesso do mesmo, onde tivemos para os protótipos sintetizados, absorções molares superiores a filtros comerciais. Estabelecendo assim uma nova linha de pesquisas com a utilização de chalconas em filtros solares seguros e eficientes.

Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-16T18:33:24Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_CarlaMariaUggeriNegretto.pdf: 1746117 bytes, checksum: 50d675658fbe05428861169424e0b28b (MD5) / Made available in DSpace on 2018-08-16T18:33:24Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_CarlaMariaUggeriNegretto.pdf: 1746117 bytes, checksum: 50d675658fbe05428861169424e0b28b (MD5) Previous issue date: 2014-03-28 / Vitamin E is an important agent in the prevention of skin aging, which is associated with oxidative stress generated, mainly, by free radicals. It is considered a potent antioxidant, which acts protecting membranes against lipid peroxidation. As most of the antioxidants, vitamin E has low water solubility and high sensitivity to light, heat, and oxygen, representing a problem in the preparation of cosmetic formulations. The incorporation of this important antioxidant to a nanostructure is a promising system capable of protecting the drug against degradation and making the formulation stable and acceptable for cosmetic use. Among the various nanostructured systems, we can highlight the nanostructured lipid carriers (NLC), since they present occlusive adhesive properties increasing the bioavailability of the drug in the skin. In this context, various analytical methods can be used to determine and quantify nanostructured vitamin E. Among these methods, we highlight UV spectrophotometry and UV derivative spectrophotometry (UVD) because they have low cost, are easy to use, and are simple to read the results. It is also important to evaluate the antioxidant power of these nanostructures through assays such as the ferric-reducing antioxidant power (FRAP), which is considered a simple, reproducible and inexpensive assay. The objectives of this study were to characterize the vitamin E – loaded nanoestrutured lipid carriers (NCL-VITE), to develop and to validate methods using UV and UVD spectrophotometry for the quantitative determination of vitamin E in NLC, to compare the analytical methods, and to evaluate the antioxidant activity of vitamin E and NCL-VITE, using FRAP assay. The characterization of NCL-VITE samples showed particle size of 169.20 ± 1.01 nm, 0.11 ± 0.01 polydispersity index (PDI) and zeta potential -25.50 mV ± 3.84. The analytical parameters studied in the validation by UV and UVD spectrophotometry indicated specificity, linearity, precision, accuracy and robustness of both methods. Likewise, the antioxidant activity of vitamin E and NCL-VITE evaluated using the FRAP assay was considered acceptable. We can conclude that the NCL-VITE showed good homogeneity and average diameter in acceptable range. All these features enabled the sample to be used in the development and validation of the methods. The UV and UVD spectrophotometry were considered analytical methods that can be applied with safety and reliability in the determination of NCL-VITE. Moreover, the FRAP assay showed to be simple and with good reproduction regarding vitamin E and NCL-VITE. / A vitamina E representa um importante agente na prevenção do envelhecimento cutâneo que está associado ao estresse oxidativo gerado, principalmente, pelos radicais livres. É considerada um potente antioxidante, agindo como protetor das membranas contra a lipoperoxidação. Como grande parte dos antioxidantes, a vitamina E apresenta baixa solubilidade em água e elevada sensibilidade á luz, calor e oxigênio, fazendo de seu uso um problema na elaboração de formulações cosméticas. Com isso, a incorporação deste importante antioxidante a uma nanoestrutura representa um promissor sistema capaz de proteger o fármaco contra a degradação tornando a formulação estável e aceitável para o uso cosmético. Dentre os mais variados sistemas nanoestruturados destacam-se os transportadores lipídicos nanoestruturados (NLCs) por apresentarem, principalmente, propriedades adesivas e oclusivas aumentando assim, a biodisponibilidade do fármaco na pele. Dentro deste contexto, vários métodos analíticos podem ser utilizados para identificar e quantificar a vitamina E nanoestruturada, dentre eles a espectrofotometria ultravioleta (UV) e espectrofotometria ultravioleta derivada (UVD) que se destacam pelo custo baixo, fácil utilização e interpretação simples dos resultados. Evidencia-se também a importância da avaliação do poder antioxidante destas nanoestruturas através de ensaios como o FRAP (poder antioxidante por redução do ferro) considerado um ensaio simples, reprodutível e pouco dispendioso. Os objetivos deste estudo foram caracterizar as suspensões de NCLs contendo vitamina E (NVITE), desenvolver e validar métodos através da espectrofotometria UV e UVD para a determinação quantitativa de vitamina E nos NLCs, comparar os métodos analíticos e avaliar a atividade antioxidante da vitamina E e da NVITE através do ensaio FRAP. Como resultado da caracterização das amostras de NVITE, estas apresentaram tamanho de partícula de 169,20 nm ± 1,01, índice de polidispersão (PDI) 0,11 ± 0,01 e potencial zeta -25,50 mV ± 3,84. Os parâmetros analíticos estudados na validação por espectrofotometria UV e UVD indicaram especificidade, linearidade, precisão, exatidão e robustez de ambos os métodos. Da mesma forma, a capacidade antioxidante da vitamina E e da NVITE feita através do ensaio FRAP foi considerada satisfatória. Concluiu-se que a NVITE analisada apresentou boa homogeneidade e diâmetro médio em escala aceitável, sendo que todas estas características a capacitaram para o uso no desenvolvimento e validação dos métodos. A espectrofotometria UV e UVD foram consideradas métodos analíticos que podem ser aplicados com segurança e confiabilidade na determinação das NVITE e o ensaio FRAP demonstrou ser simples, e com boa reprodutibilidade no que se refere a vitamina E e a NVITE.

Orientador: Carlos Kenichi Suzuki / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-05T09:52:20Z (GMT). No. of bitstreams: 1 Marcuz_Nadia_M.pdf: 2618186 bytes, checksum: bf57e53a2d504fb7eb70931387caa188 (MD5) Previous issue date: 2005 / Resumo: O tratamento por plasma térmico de resíduos hospitalares gera como subproduto um material vitrocerâmico com alto poder de bloquear radiação ultravioleta e infravermelho próximo. A composição deste material apresenta como elementos majoritários cálcio, silício, ferro, alumínio e oxigênio. O objetivo deste trabalho é compreender a cinética de devitrificação das múltiplas fases do vitrocerâmico pelo controle do tratamento térmico e o seu efeito na absorção de radiação ultravioleta. Determinou-se por análise térmica diferencial as temperaturas de fusão e recristalização. Amostras vítreas obtidas por fusão a 1300 °C seguido por resfriamento rápido foram tratadas termicamente para induzir a devitrificação. Através da técnica de difração de raios-X identificou-se três estruturas cristalinas, Mg(Al,Fe)2O4, Ca(Ti,Mg,Al)(Si,Al)2O6 e NaAlSiO4, e determinou-se o tamanho médio e quantidade dos cristalitos presentes nessas fases com as diferentes temperaturas de tratamento térmico. As fases cristalinas formadas exercem influência na absorção óptica na faixa de ultravioleta, possibilitando a aplicação deste vitrocerâmico como agente ativo em bloqueadores ultravioleta comerciais. Medidas de transmitância óptica mostraram que o crescimento das fases Ca(Ti,Mg,Al)(Si,Al)2O6 e NaAlSiO4 induziram um fator de redução de 55% para 6% nos valores de transmitâncias ópticas no espectro ultravioleta (290 a 400 nm). A relevância deste trabalho revela-se no controle da formação das fases cristalinas do material que contribuem efetivamente na absorção da radiação ultravioleta / Abstract: A glass-ceramic material generated by plasma treatment of hospital waste has a remarkable property to block ultraviolet and near infrared radiation. The main composition elements of such a glass-ceramic are: calcium, silicon, iron, aluminum and oxygen. The objective of the present research is to understand the kinetics of devitrification of multiple phases by the control of thermal treatment conditions, and their effect on the ultraviolet absorption. The melting and crystallization temperatures of the glass-ceramic material were determined by differential thermal analysis. Vitreous samples were obtained by melting the as-received material at 1300 °C, followed by quenching. Afterwards, samples were thermally treated, inducing controlled crystallization. By X-ray diffraction technique, three crystalline phases were identified: Mg(Al,Fe)2O4, Ca(Ti,Mg,Al)(Si,Al)2O6 and NaAlSiO4. Average size and concentration of the crystallites were also determined. The formed crystalline phases have strong influence in the optical absorbance at ultraviolet band, which allows this glass-ceramic to be used as an active agent in commercial ultraviolet blockers. Optical transmittance measurements showed that the growth of nano-order crystalline phases Ca(Ti,Mg,Al)(Si,Al)2O6, and NaAlSiO4 reduced the optical transmittance from a factor of 55% to 6% at the ultraviolet band (290 to 400 nm). The relevance of this work is shown on the effect of size and concentration of crystalline phases, that contributes to the optical absorption of ultraviolet radiation / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Lorsque l’on veut sonder les structures internes de sources astronomiques non résolues par nos instruments modernes, la technique de la spectropolarimétrie a démontré etre une méthode à la fois indépendante et complémentaire des analyses spectrales et temporelles. Dans cette thèse, j’explore de façon théorique le signal de polarisation résultant des Noyaux Actifs de Galaxies (NAG en français, AGN en anglais), dans lesquels on suppose que l’énergie radiative principale est crée paraccrétion autour d’un trou noir super-massif et qu’une partie importante des échappements de matère se fait sous la forme de vents d’éjection. Selon le Schéma Unifié des NAG, l’émission radiative résultante est fortement anisotrope, due au confinement des photons par un corps de poussère obscurcissant situé au niveau du plan équatorial. Les radiations sont donc forcées de s’échapper dans les directions polaires, photo-ionisant au passage les vents d’éjection coniques. Cette configuration asymétrique permet de justifier la dichotomie observationnelle des NAG en fonction de leur inclinaison spatiale; cependant, leurs propriétés difèrent aussi en fonction de la bande énergétique d’observation. Donc, afin de vérifier la stabilité du moèle unifié, il est nécessaire de le tester sur de multiples échelles de longueur d’onde afin d’en déduire de fortes contraintes morphologiques. / When probing the inner structures of unresolved astrophysical sources, spectropolarimetry has proven to be a solid tool, both independent and complementary to spectral and timing analyses. In this thesis, I theoretically explore the polarization of Active Galactic Nuclei (AGN), which are powered by accretion onto supermassive black holes and often reveal significant mass outflows. Their emission is strongly anisotropic and the standard model of AGN postulates that the anisotropy is caused by a confinement of the radiation in the funnel of an obscuring body of circumnuclear dust; the radiation is thus forced to escape along the funnel where it photo-ionizes conically shaped outflows. The asymmetrical configuration explains an observational dichotomy where AGN properties are characterized according to the observer’s line-of-sight. However, AGN observations differ significantly from one waveband to another and the broadband validity of the unified model has to be tested by a method that gives strong constraints on the AGN morphology. In this thesis, I subsequently investigate how morphological and composition constraints on the different substructures in thermal, radio-quiet Active Galactic Nuclei can be deduced from optical, UV and X-ray polarization properties.

We have observed our Universe in many different wavelengths, from gamma ray to radiowaves and have observed countless stars, galaxies, and everything else in between. These measurements slowly add to our understanding of what our Universe is, how it formed, and where it is heading next. In Chapter 2 we introduce the Ultraviolet GAlactic Plane Survey (UVGAPS), which produced a high resolution map of the Milky Way’s Galactic plane in the NUV using the Galaxy Evolution Explorer (GALEX), an orbiting ultraviolet space telescope operated by NASA and Caltech between 2003-2013. Of the many astrophysical phenomena observable in ultraviolet wavelengths, we choose to focus on a few interesting objects: red clump stars and OB type stars, and the Galactic dust that impacts them. We use an image source extractor to obtain the NUV photometry and apply several cuts to clean the data. We present a catalog of 2,843,399 objects with GALEX NUV band mea- surements. Despite the difference in observing strategy and analysis pipeline, we find good agreement between previously targeted GALEX observations and the UVGAPS catalog in overlapping regions. The data were cross matched to Gaia DR2 and Pan-STARRS DR2, two visible-band surveys that have considerable coverage of the Galactic Plane. We characterize matched objects in color-magnitude and color-color space to highlight a range of objects, from main sequence stars to binaries detected with these data. Although core helium-burning red clump (RC) stars are faint at ultraviolet wavelengths, their ultraviolet-optical color is a unique and accessible probe of their physical properties. In Chapter 3, using data from the GALEX All Sky Imaging Survey, Gaia DR2, and the SDSS APOGEE DR14 survey, we find that spectroscopic metallicity is strongly correlated with the location of a RC star in the UV-optical color magnitude diagram. The RC has a wide spread in (NUV - G)0 color of over 4 magnitudes compared to a 0.7-magnitude range in (G BP - G RP )0 . We propose a photometric, dust-corrected, ultraviolet-optical (NUV - G)0 - [Fe/H] color-metallicity relation using a sample of 5,175 RC stars from APOGEE. We show that this relation has a scatter of 0.16 dex and is easier to obtain for large, wide-field samples than spectroscopic metallicities. Importantly, the effect may be comparable to the spread in RC color attributed to extinction in other studies. In Chapter 4 we extend our RC analysis to UVGAPS and include new age and mass measurements. We find that RC stars separate into two distinct populations in the thin and thick disk. Thick disk stars tend to be old, low mass stars while thin disk stars are more heterogeneous, containing mostly young, massive stars but also some old, low-mass stars typical of the thick disk. These last two chapters are just two of many projects that UVGAPS enables.

Solar-blind Ultraviolet cameras are used to detect missile plumes and perform the detection of corona on high voltage electrical lines. This study investigates the influence of the spectral transfer function of a specific solar-blind Ultraviolet camera upon Ultraviolet energy measurement results. In addition to the spectral transfer response investigated, is the influence of other related factors, including the specific camera operation and design. The possibility that the particular camera‟s measurements are being influenced by its own spectral transfer function, is initially investigated by using a simplified model. The objective of the model was to determine if the hypothesis is possible. In addition to the spectral transfer function of the camera, other factors that could influence camera measurements were also investigated in the literature. Included are highlights from other research conducted utilising this type of camera for high voltage electrical purposes, as well as comments for further research. Subsequently experiments were executed to characterise the camera, including the determination of the spectral transfer function of the specific camera, taking into considering limitations of the camera and related equipment. Derived from the spectral transfer of the camera and the other experiments and literature, a proposed method of calibration is presented, as well as suggestions for the improvement of the camera and better utilisation thereof. / Son-blind ultraviolet kameras word gebruik om missiel uitlaat gasse sowel as korona op hoogspannings kraglyne op te spoor. Die studie ondersoek die invloed van die spektrale oordragfunksie van „n spesifieke son-blind ultraviolet kamera op ultraviolet energie meetingsresultate. Addisioneel tot die spektrale response geondersoek, is die invloed van ander verwante faktore op metings insluitend die spesifieke kamera se werking en ontwerp. Die moontlikheid dat die spesifieke kamera se metings beïnvloed word deur sy eie spektrale oordragfunksie, word aanvanklik eers ondersoek aan die hand van ‟n eenvoudige model. Die doel van die model is om te bepaal of die hipotese moontlik is. Addisioneel tot die spektrale oordragfunksie van die kamera, word ander faktore wat die kamerametings kon beïnvloed het, ook ondersoek in die literatuur. Ingesluit is hoogtepunte van ander navorsing wat die tipes kameras gebruik vir hoogspannings elektriese doeleindes, plus kommentaar vir verdere navorsing. Vervolgens is eksperimente uitgevoer om die kamera te karakteriseer, insluitend die bepaling van die spesifieke kamera se spektrale oordragfunksie, met inagneming van die beperkings van kamera en verwante toerusting. Afgelei uit die spektrale oordragfunksie van die kamera en die ander eksperimente en literatuurstudie, is „n voorgestelde kalibrasiemetode aangebied, asook voorstelle vir die verbetering en die kamera en meer effektiewe gebruik daarvan. / Dissertation (MEng (Electronic Engineering))--University of Pretoria, 2015. / Electrical, Electronic and Computer Engineering / MEng (Electronic Engineering) / Unrestricted

L'effet de l'orientation des carottes durant l'exposition aux rayons UV-C sur la résistance à Botrytis cinerea et l'accumulation de phytoalexine, la 6-méthoxymelléine (6-MM), ainsi que la nature de cette résistance ont été étudiés pour 2 cultivars de carotte (Carochoice et Sun 255). Les carottes ont été exposées aux rayons UV-C suivant 2 orientations : i) l'orientation verticale où la face latérale était couverte ou non de papier aluminium, et ii) l'orientation horizontale où les carottes étaient tournées 2 ou 4 fois. Les doses hormiques pour les orientations verticale et horizontale étaient de 8.1 et 5.4 kJ.m" respectivement. La résistance et l'accumulation de la 6-MM étaient maximales lorsque les carottes orientées horizontalement étaient exposées à une dose de 5.4 kJ.m'2 et tournées 2 ou 4 fois. Il a été également montré que la 6-MM joue un rôle clé dans la résistance des carottes induite suite aux traitements UV-C et que la variété Carochoice, qui accumule plus de 6-MM, serait plus résistance à Botrytis cinerea et répond mieux aux traitements aux UV-C que la variété Sun 255. La résistance induite par l'application des rayons UV-C est locale, ce qui suggère que toute la surface des carottes doit être exposée aux radiations pour que la résistance induite soit maximale.

Master of Science / Department of Chemical Engineering / Larry E. Erickson / The damage that can be inflicted by ultraviolet radiation has gained widespread interest. Traditionally sunscreens are made of organic and inorganic components that block two of the three types of ultraviolet radiation, UVA and UVB. This report is a literature review of several articles that have investigated the effects of inorganic UV filters; specifically titanium dioxide and cerium dioxide. There are concerns about absorption of titanium dioxide into the skin and the adverse reactions that could occur, but it was found that there is little to no absorption. Similarly the photostability of titanium dioxide is a concern; this was found to be remedied in part by a surface treatment to the titanium dioxide. The combination of titanium dioxide and carnauba wax was also studied and found to enhance the properties of both the organic and inorganic filters. Ceria was studied as a possible replacement for titanium dioxide. It was found to have similar ultraviolet shielding properties while minimizing the photocatalytic activity and photocytotoxicity seen in titanium dioxide.