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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.
221

Remote sensing of sulfur dioxide (SO2)using the Lineate Imaging Near-Ultraviolet Spectrometer (LINUS) /

Khoo, Sing Soong. January 2005 (has links) (PDF)
Thesis (M.S. in Systems Engineering (EW))--Naval Postgraduate School, March 2005. / Thesis Advisor(s): Richard M. Harkins, Richard C. Olsen. Includes bibliographical references (p. 53). Also available online.
222

Secondary structure in three tRNA's as studied by D2O and cyclodextrin perturbation of their ultraviolet spectra

Hoffman, Jerald Lee, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
223

Rôle de la glutathion peroxydase dans la réponse cellulaire aux rayons ultraviolets B /

Cossette, Chantal. January 1997 (has links)
Thèse (M.Sc.) -- Université Laval, 1997. / Bibliogr.: f. 60-76. Publié aussi en version électronique.
224

Ultraviolet inactivation and optimized recovery strategies for viruses on fresh produce

Fino, Viviana R. January 2007 (has links)
Thesis (M.S.)--University of Delaware, 2007. / Principal faculty advisor: Kalmia Kniel, Dept. of Animal & Food Sciences. Includes bibliographical references.
225

Effect of transmittance and suspended soils on the efficacy of UV disinfection of bacterial contaminants in water

Ha Thi Nguyen. January 1999 (has links) (PDF)
Errata pasted onto front end-paper. Bibliography: leaves 113-120. To obtain robust and quantitative data on the influence of UV absorption and suspended solids on UV disinfection an experimental study using commercial disinfection technology was undertaken.
226

Modification of organic polymers with vacuum ultraviolet radiation from inert gas plasmas rotating in a magnetic field /

Chen, Jian-Xin. January 1990 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1990. / Typescript. Includes bibliographical references (leaves 72-75).
227

Estudo dos marcadores cutâneos indicadores de risco para carcinoma basocelular

Chinem, Valquiria Pessoa [UNESP] 10 June 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-10Bitstream added on 2014-06-13T19:15:37Z : No. of bitstreams: 1 chinem_vp_me_botfm.pdf: 1046536 bytes, checksum: b5e64bea756306e2b54ffb56b99c094a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O carcinoma basocelular é a neoplasia maligna mais comum em humanos e sua incidência vem aumentando nas últimas décadas. Sua grande frequência gera significativo ônus ao sistema de saúde configurando problema de saúde pública. Apesar das baixas taxas de mortalidade e de rara ocorrência de metástases, o tumor pode apresentar comportamento invasivo local e recidivas após o tratamento, gerando importante morbidade. Exposição à radiação ultravioleta representa o principal fator de risco ambiental associado a sua gênese. Entretanto, descrevem-se outros elementos de risco como: fototipos claros, idade avançada, história familiar de carcinomas de pele, olhos e cabelos claros, sardas na infância e imunossupressão, além de aspectos comportamentais como: exercício profissional exposto ao sol, atividade rural e queimaduras solares na juventude. Entre 30% e 75% dos casos esporádicos estão associados à mutação do gene patched hedgehog, mas outras alterações genéticas são ainda descritas. A neoplasia é comumente encontrada concomitantemente a lesões cutâneas relacionadas à exposição solar crônica como: queratoses actínicas, lentigos solares e telangiectasias faciais. A prevenção do carcinoma basocelular está baseada no conhecimento de fatores de risco, no diagnóstico e tratamento precoces além da adoção de medidas específicas, principalmente nas populações susceptíveis. Os autores apresentam uma revisão da epidemiologia do carcinoma basocelular / The basal cell carcinoma is the most common malignant human neoplasm, and its incidence has increased over the last decades. Its high frequency generates significative costs to the health system constituting a public health problem. Despite the low mortality rates and rare occurrences of metastases, the tumor may present local invasive behavior and relapses after treatment, producing a significant morbidity rate. Exposure to ultraviolet radiation is the most important environmental risk factor associated to its genesis. However, other risk factors are also described such as: fair skin types, aging, family history of skin cancer, fair hair and light eyes, freckles in childhood, and imunosuppression. Behavioral aspects like occupational sun exposure, rural activity, and sunburns at young age are also risk factors. Between 30% and 60% of sporadic cases are associated to patched hedgehog gene mutation, but further genetic changes are also described. This neoplasm is frequently accompanied by cutaneous lesions associated to chronic solar exposure such as: actinic keratosis, solar lentigo, and facial telangectasias. Prevention of basal cell carcinoma is based on the knowledge of risk factors, early detection and treatment, besides the adoption of specific measures mainly in susceptible populations. The authors present a revision of the epidemiology of basal cell carcinoma
228

Aspects of olefinic coordination chemistry

Denning, R. G. January 1964 (has links)
No description available.
229

Ultraviolet specular reflectance, electronic absorption and the excitation of fluorescence in single crystals of anthracene

Wright, W H January 1966 (has links)
From introduction: The Fluorescence Excitation Spectrum or anthracene is known to vary considerably with the age and condition or the crystal. This thesis represents an attempt to improve the understanding of these variations. To put the problem on a quantitative basis it was found necessary to know both the ultraviolet reflection and absorption spectra. Reports of the reflection spectrum appear to have been confined to the case of polarised incident light. In addition the reflectivity measurements are always reported for a freshly cleaved surface. For these reasons the reflectivity of anthracene for various conditions of the reflecting surface was measured with unpolarised light. These varying reflectivities were used to further knowledge of the chemical processes at the crystal surface, as well as being used directly in the calculation of fluorescence excitation spectra. Reflection spectra with a- and b- crystallographic axis polarisations were also obtained. Since such spectra are reported in the literature it was possible, by comparison, to conclude that the experimental methods used in this thesis yielded valid results. The polarised measurements were used to obtain optical constants for the crystal. In the interests of readability most of the complicated process of converting the reflectivities to optical constants is dealt with in three appendices to the thesis.
230

Determination of the effects of sunlight and UV irradiation on the structure, viability and reapplication frequency of the biopesticide cryptophlebia leucotreta granulovirus in the protection against false codling moth infestation of citrus crops

Mwanza, Patrick January 2015 (has links)
Cryptophlebia leucotreta granulovirus (CrleGV-SA) is a baculovirus specifically pathogenic to the citrus pest false codling moth, Thaumatotibia leucotreta. CrleGV- SA is formulated as a commercial biopesticide, Cryptogran® (River Bioscience, South Africa). The virus has a stable, proteinaceous crystalline occlusion body (OB) that protects the nucleocapsid. The major limitation to the use of baculoviruses is their susceptibility to the ultraviolet (UV) component of sunlight, which rapidly and greatly reduces their efficacy as biopesticides. The UVA and UVB components are the most destructive to biological organisms. To date no publication has reported the effect of UV on the structure and virulence of CrleGV, or the effectiveness of the OB as a UV protectant. In this study the effect of UV irradiation on the structure and infectivity of pure CrleGV-SA and Cryptogran® was investigated using scanning electron microscopy (SEM), Raman spectroscopy, qPCR, and bioassays. The project included laboratory and field studies. In the laboratory, CrleGV-SA and Cryptogran® were exposed to either UVA or UVB for periods of 24 hours to 7 days before analysis. In the field, Cryptogran® was applied to trees in a citrus orchard with young fruit. The fruit were collected from 24 hours to 28 days after application and bioassays conducted to assess the effect of sunlight over time on virus structure and efficacy when applied to the northern or southern sides of the trees. No surface morphological changes to the virus were detected using SEM. However, small compositional changes were detected by Raman spectroscopy. qPCR and bioassays demonstrated that UV irradiation damaged the viral DNA, greatly reducing the infectivity of pure CrleGV-SA and Cryptogran®. Exposure to UVB reduced the virulence of the virus more than UVA. The field studies revealed that the activity of CrleGV-SA decreased more on the northern side of the trees than on the southern side.

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