Spelling suggestions: "subject:"[een] UV"" "subject:"[enn] UV""
91 |
Understanding the Effect of Wastewater Flocs Properties on UV Disinfection KineticsArmioun, Shaghayegh 20 November 2013 (has links)
Wastewater microbial flocs can protect microorganisms from inactivation by UV light. This effect is detected as tailing at high UV doses in the UV dose response curve. A double-layer structure composed of an inner compact core surrounded by a loose outer layer was proposed by earlier studies to describe UV resistance of microbial flocs. Due to limited oxygen diffusion into the compact cores, the UV inactivation of compact cores and microbial flocs under anaerobic conditions needed to be addressed. The UV disinfection kinetics under anaerobic culturing condition was nearly identical to that of the aerobic study. Moreover, the role of iron concentration on the differences in the UV inactivation kinetics of flocs and cores was assessed. The increase in UV absorbance of floc material due to iron addition could dominate the UV disinfection kinetics of flocs and cores such that they exhibited similar UV disinfection kinetics.
|
92 |
TC-NER dans le gène de l'ARN ribosomal 35S chez Saccharomyces cerevisiaeZeledon, Carlos January 2013 (has links)
Divers agents environnementaux peuvent causer des dommages à l’ADN qui, si non réparés, peuvent mener à des mutations et éventuellement le cancer. Des mécanismes de réparation sont donc nécessaires afin de maintenir l’intégrité du génome. Un de ces mécanismes est la réparation par excision de nucléotides (NER) qui va réparer des dommages qui causent une distorsion dans l’hélice d’ADN comme ceux formés par les rayons UV. La NER se divise en deux sous-voies : la réparation global du génome (GGNER), responsable de réparer l’ADN transcriptionnelement inactif ainsi que le brin nontranscrit de gènes actifs, et la réparation couplée à la transcription(TC-NER), responsable de réparer le brin transcrit de gènes actifs. La TC-NER ne diffère de la GG-NER que par la méthode de reconnaissance du dommage et va réparer les dommages plus rapidement que la GG-NER. Chez Saccharomyces cerevisiae, les gènes de l’ARN ribosomal peuvent exister en 2 états distinct dans la cellule, soit actifs et transcrits par l’ARN polymerase I ou soit inactifs et recouverts de nucléosomes. Des études ont démontré que suite à une irradiation aux UV, il y avait fermeture des gènes ribosomaux actifs et réouverture au fur et à mesure que les dommages sont réparés. De plus, il a été démontré, qu’après irradiation, il y avait une présence plus importante d’ARN polymerase I au début du gène qu’à la fin. Ces évidences suggèrent que la TC-NER va réparer les dommages au début du gène et que son influence va diminuer au fur et à mesure qu’on avance dans le gène. Ainsi, les travaux présentés dans ce mémoire vise à évaluer l’impact de la TC-NER sur la cinétique de réparation de l’ADN ribosomal. À cet effet, une série d'extension d’amorces ont été effectuées dans différentes régions du gène de l’ARN ribosmal 35S. Ces analyses ont montré que la réparation des dommages UV au début du gène est médiée par la TCNER alors que plus loin dans le gène, la réparation est médiée en plus grande partie par la GG-NER. De plus, l’analyse de la réparation dans la région terminatrice de la transcription a montré que la TC-NER s’arrête au site principal de terminaison T1 dans une souche WT. Alors que dans une souche ayant un défaut dans le terminaison de la transcription, rpal2A, la TC-NER arrête au site terminaison secondaire T2. Dans une autre souche déficiente dans la terminaison, nsi1[triangle], le TC-NER n’est pas détectable après le site T1, mais une réparation plus rapide est observée après le site T2. [symboles non conformes]
|
93 |
The effects of water treatment works on chlorine decay and THM formationHua, Fang January 2000 (has links)
No description available.
|
94 |
Measurements of Atmospheric Ozone, NO2, OClO, and BrO at 80°N using UV Visible SpectroscopyAdams, Cristen 06 December 2012 (has links)
The motivation for this thesis was to study chemical and dynamical processes in the Arctic stratosphere, using data from two ground-based spectrometers (GBSs). The GBSs took atmospheric trace gas measurements at the Polar Environment Atmospheric Research Laboratory (PEARL), which is located at Eureka, Nunavut, Canada (80.05°N, 86.42°W) and operated by the Canadian Network for the Detection of Atmospheric Change. The University of Toronto GBS took measurements at Eureka on a campaign basis from 1999 2011. The PEARL GBS was installed permanently at Eureka in 2006 and has taken measurements during the sunlit part of the year since then.
GBS and other ground based ozone and NO2 column measurements were compared with Atmospheric Chemistry Experiment (ACE) and Optical Spectrograph and Infra Red Imaging System (OSIRIS) satellite measurements above Eureka. Ozone from all instruments agreed within 9.2%, while NO2 from most instruments, including the GBS, agreed to within 20%.
On 1 August 2008, a solar eclipse of 98% totality passed over Eureka. GBS NO2 increased to 1.84 times normal levels. This agrees with a ratio of 1.91 that was calculated using a photochemical model, adjusted for reduced sunlight during the eclipse.
In spring/winter 2011, up to 47% (250 DU) ozone loss was calculated using GBS and modeled passive ozone. This was the largest ozone loss in the 11 year GBS measurement record. GBS OClO was elevated, indicating chlorine activation and NO2 was low, suggesting denitrification. GBS, satellite, and chemical transport model data were used to investigate the 2011 vortex breakup. NOx transport led to middle stratosphere ozone loss within an anticyclone. Furthermore, isolated, or “frozen-in”, vortex and lower-latitude airmasses were observed following the vortex breakup.
Stratospheric BrO was retrieved from spring 2008 GBS zenith sky measurements, using an optimal estimation technique. GBS BrO was compared with OSIRIS and Ozone Monitoring Instrument (OMI) satellite data. Discrepancies are partly attributed to bromine explosions in the boundary layer. New off axis GBS measurements taken in spring 2010 are sensitive to boundary layer bromine. The combination of GBS stratospheric and tropospheric BrO measurements will be useful for future estimates of the Arctic bromine budget.
|
95 |
Identification and Characterization of a Novel CK2-MSK2 Iinteraction in the UV ResponseJacks, Kellie A. 11 April 2011 (has links)
CK2 is a ubiquitous serine/threonine protein kinase implicated in numerous cellular processes as well as in tumorigenesis. CK2 is composed of two catalytic (αα, αα’, α’α’) subunits and two regulatory (ββ) subunits that assemble to form the active CK2 holoenzyme. CK2 has been shown to phosphorylate, interact with, and regulate other proteins, including other protein kinases. CK2 substrates can be initially bound by the CK2β regulatory subunit, which acts as a docking site to facilitate phosphorylation and mediate CK2 substrate specificity. In a screen to identify novel CK2β interacting proteins, I identified three novel CK2β interactors, including the mitogen- and stress-activated kinase 2 (MSK2), which I pursued for further characterization.
MSK2, and the closely related isoform MSK1, are nuclear kinases that are activated following mitogen stimulation or cellular stress, including UV radiation, by the ERK1/2 and p38-MAPK signaling cascades, respectively. However, factors that differentially regulate MSK1 and MSK2 have not been well characterized. In my thesis, I demonstrate that CK2, which contributes to NF-κB activation following UV radiation in a p38-dependent manner, physically interacts with MSK2 but not MSK1 and that CK2 inhibition specifically impairs UV-induced MSK2 kinase activation. A putative site of CK2 phosphorylation was mapped to MSK2 residue serine-324 and when substituted to alanine (S324A) also compromised MSK2 activity. RNA interference-mediated depletion of MSK2 in human MDA-MB-231 cells, but not MSK1 depletion, resulted in impaired UV-induced phosphorylation of NF-κB p65 at serine-276 in vivo, which was restored by the ectopic expression of MSK2 but not by MSK2-S324A. Furthermore, UV-induced p65 transactivation capacity was dependent on MSK2, MSK2 residue S324, and p65-S276. These results suggest that MSK1 and MSK2 are differentially regulated by CK2 during the UV response and that MSK2 is the major protein kinase responsible for the UV-induced phosphorylation of p65 at S276 that positively regulates NF-κB activity in MDA-MB-231 cells.
|
96 |
Measurements of Atmospheric Ozone, NO2, OClO, and BrO at 80°N using UV Visible SpectroscopyAdams, Cristen 06 December 2012 (has links)
The motivation for this thesis was to study chemical and dynamical processes in the Arctic stratosphere, using data from two ground-based spectrometers (GBSs). The GBSs took atmospheric trace gas measurements at the Polar Environment Atmospheric Research Laboratory (PEARL), which is located at Eureka, Nunavut, Canada (80.05°N, 86.42°W) and operated by the Canadian Network for the Detection of Atmospheric Change. The University of Toronto GBS took measurements at Eureka on a campaign basis from 1999 2011. The PEARL GBS was installed permanently at Eureka in 2006 and has taken measurements during the sunlit part of the year since then.
GBS and other ground based ozone and NO2 column measurements were compared with Atmospheric Chemistry Experiment (ACE) and Optical Spectrograph and Infra Red Imaging System (OSIRIS) satellite measurements above Eureka. Ozone from all instruments agreed within 9.2%, while NO2 from most instruments, including the GBS, agreed to within 20%.
On 1 August 2008, a solar eclipse of 98% totality passed over Eureka. GBS NO2 increased to 1.84 times normal levels. This agrees with a ratio of 1.91 that was calculated using a photochemical model, adjusted for reduced sunlight during the eclipse.
In spring/winter 2011, up to 47% (250 DU) ozone loss was calculated using GBS and modeled passive ozone. This was the largest ozone loss in the 11 year GBS measurement record. GBS OClO was elevated, indicating chlorine activation and NO2 was low, suggesting denitrification. GBS, satellite, and chemical transport model data were used to investigate the 2011 vortex breakup. NOx transport led to middle stratosphere ozone loss within an anticyclone. Furthermore, isolated, or “frozen-in”, vortex and lower-latitude airmasses were observed following the vortex breakup.
Stratospheric BrO was retrieved from spring 2008 GBS zenith sky measurements, using an optimal estimation technique. GBS BrO was compared with OSIRIS and Ozone Monitoring Instrument (OMI) satellite data. Discrepancies are partly attributed to bromine explosions in the boundary layer. New off axis GBS measurements taken in spring 2010 are sensitive to boundary layer bromine. The combination of GBS stratospheric and tropospheric BrO measurements will be useful for future estimates of the Arctic bromine budget.
|
97 |
Studying polymer degradation at a molecular level via soft ionisation mass spectrometryBennet, Francesca, Chemical Sciences & Engineering, Faculty of Engineering, UNSW January 2009 (has links)
The present study employs a range of soft-ionisation mass spectrometry techniques to study the degradation of model compounds of poly(methyl methacrylate), poly(n-butyl acrylate) and poly(2-hydroxyethyl methacrylate) under conditions designed to simulate the worst-case scenario that would be experienced by a polymer used in a surface coating on a steel roof. Vinyl-terminated and saturated polymers were degraded for periods of up to 2 years under simulated solar radiation at a temperature of 95??C, temperature of 95 ??C in the dark, and simulated solar radiation at 35??C. Similar degradation mechanisms were observed under heat and UV radiation. The presence of UV radiation accelerated the degradation occurring at high temperature, and vice versa. The combination of heat and UV radiation is far more detrimental to the polymers than either of these conditions alone. Both vinyl-terminated and saturated pMMA degraded under UV radiation at 95??C, whereas under conditions of UV radiation alone or high temperature alone, the saturated polymer was found to be stable. The vinyl-terminated pMMA degrades in all cases via the formation of ethylene oXide-type end groups, which subsequently rearrange under the expulsion of formaldehyde and 2-oxo-propionic acid methyl ester. This is in contrast to all previous literature, in which pMMA degrades via depolymerisation and is stable at 95??C. Degradation of pBA included a degradation mechanism similar to that of pMMA in addition to other polymer fragments, some of which cannot be assigned. pBA (both saturated and vinyl-terminated) showed a tendency to crosslink under all degradation conditions in this study. Only saturated pHEMA was stable under thermal degradation. In all other cases, pHEMA showed some degradation, but displayed a much greater tendency to crosslink rapidly. Terminal vinyl bonds were shown in all cases to be a weak point in the polymer with respect to degradation. pMMA was found to be the least reactive of these polymers. pHEMA showed some small degradation but had a greater tendency to crosslink via the hydroxyethyl side groups. pBA does not have any such reactive groups, and its crosslinking reaction may be explained via the acrylate backbone, or the longer alkyl ester group.
|
98 |
Transferência do nifedipino para o leite materno em lactantes hipertensas. / Transfer of nifedipine to breast milk in hypertensive lactant women.Malfará, Bianca Nayra 31 October 2017 (has links)
Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-11-28T23:49:33Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-11-30T18:58:21Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-04T14:43:23Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-05T14:11:15Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-11T18:47:11Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-14T11:25:04Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-14T13:50:33Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Submitted by BIANCA NAYRA MALFARA null (bia_malfara@yahoo.com.br) on 2017-12-21T12:31:27Z
No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Approved for entry into archive by Maria Irani Coito null (irani@fcfar.unesp.br) on 2018-01-12T18:49:09Z (GMT) No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5) / Made available in DSpace on 2018-01-12T18:49:09Z (GMT). No. of bitstreams: 1
dissertacao_bianca_nayra_malfara_nov_28_2017.pdf: 1786217 bytes, checksum: 0ba0c54c5baf2896a8498af722318646 (MD5)
Previous issue date: 2017-10-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente estudo foi avaliar a transferência do nifedipino para o leite materno no estado de equilíbrio em lactantes hipertensas tratadas com comprimidos de liberação controlada na dose de 20 mg a cada 12 horas. Nossa hipótese de trabalho foi a de que o polimorfismo genético ABCG2 c.421C>A pudesse alterar a razão de concentração de nifedipino no leite/plasma (L/P) das lactantes portadoras de pelo menos um alelo raro. Foram investigadas 15 pacientes com hipertensão arterial sistêmica durante atendimento pré-natal no Serviço de Ginecologia e Obstetrícia da Faculdade de Medicina de Ribeirão Preto, da Universidade de São Paulo. No período de quinze a trinta dias pós-natal e após pelo menos 15 dias de tratamento com o nifedipino (estado de equilíbrio), foram coletadas simultaneamente amostras de sangue e leite materno. As concentrações de nifedipino plasmáticas e no leite materno foram avaliadas por cromatografia líquida de alta eficiência com detecção por ultravioleta (CLAE-UV). O método de determinação do nifedipino no plasma foi linear no intervalo de 10 a 150 ng/mL e no leite de 5 a 100 ng/mL. Os métodos mostraram detectabilidade, linearidade, precisão, exatidão e estabilidade compatíveis com a determinação do nifedipino em pacientes em uso crônico do fármaco. A concentração de nifedipino no plasma das lactantes variou de 11,8 a 178,1 ng/mL (mediana: 46,0 ng/mL). A concentração no leite materno humano foi similar à encontrada no plasma, variando de 5,2 a 93,8 ng/mL (mediana: 13,9 ng/mL). Não houve correlação positiva entre a concentração de nifedipino no plasma e no leite materno (p=0,3936). A razão de concentrações leite/plasma variou de 0,06 a 2,52 e não apresentou correlação com o índice de massa corpóreo (p=0,6290), idade (p=0,1071) ou clearance de creatinina (p=0,4427). Não houve influência de ABCG2 421C>A nas 15 pacientes investigadas na razão L/P, mas a investigação de um número maior de pacientes é necessária para concluir essa análise. / 1480500
|
99 |
Irrigação de hortaliças utilizando efluente secundário desinfectado por radiação solar / Irrigation of vegetables using secondary effluent disinfected by solar radiationSales, Mariana Alexandre de Lima [UNESP] 16 April 2018 (has links)
Submitted by MARIANA ALEXANDRE DE LIMA SALES (mal_sales@hotmail.com) on 2018-06-12T12:50:35Z
No. of bitstreams: 1
SALES, M. A. L..pdf: 7923463 bytes, checksum: aea4ad742d611dfc186574ff6757fc13 (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-06-12T13:46:52Z (GMT) No. of bitstreams: 1
sales_mal_dr_botfca.pdf: 7897015 bytes, checksum: b7243b1e5eb4c54c46e59e28fe2cedc0 (MD5) / Made available in DSpace on 2018-06-12T13:46:52Z (GMT). No. of bitstreams: 1
sales_mal_dr_botfca.pdf: 7897015 bytes, checksum: b7243b1e5eb4c54c46e59e28fe2cedc0 (MD5)
Previous issue date: 2018-04-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Associar o tratamento de água residuária doméstica (ARD) ao o uso pela agricultura familiar pode ser uma alternativa viável para a sustentabilidade ambiental no meio agrícola. No entanto, ainda são necessários diversos estudos sobre a reutilização desta água. O experimento foi realizado no Departamento de Engenharia Rural, Faculdade de Ciências Agronômicas (FCA) – Universidade Estadual Paulista (UNESP), Fazenda Experimental Lageado, no município de Botucatu, São Paulo, o qual consistiu em verificar diferentes porcentagens (0, 25, 50, 75 e 100%) de água residuária doméstica tratada, na lâmina total de irrigação e qual a relação desta com a produção, considerando a qualidade microbiológica dos produtos. Os objetivos deste trabalho foram avaliar a influência dos tratamentos estudados no entupimento da fita gotejadora, no solo e nas culturas da cebolinha ‘todo ano’, salsa ‘graúda portuguesa’ e abobrinha ‘italiana’ tanto na produção agrícola, quanto na presença de E. coli. O delineamento estatístico adotado foi em DIC (delineamento inteiramente casualizado), cada tratamento consistiu de cinco linhas laterais de irrigação, com espaçamento de 0,8 m entre linhas e de 0,3 m entre gotejadores, onde havia um emissor por planta para as culturas de cebolinha ‘todo ano’ e salsa ‘graúda portuguesa’, porém para a cultura da abobrinha ‘italiana’ o espaçamento foi de 1,2 m entre plantas. Os resultados obtidos na pesquisa foram: no solo observou-se algumas mudanças nas características químicas, notando tanto aumento como diminuição nos níveis de determinados nutrientes. O sistema de irrigação apresentou uma redução nos coeficientes de uniformidade, no entanto ainda ficaram próximos a 90%. Em relação às culturas estudadas, no geral houve um aumento linear nos valores observados em função da água residuária doméstica tratada por radiação solar - ARD-TRS nos parâmetros de altura média da planta, número médio de talos, diâmetro médio do maior talo, diâmetro médio da touceira e massa da matéria fresca e seca, para as culturas de cebolinha ‘todo ano’ e salsa ‘graúda portuguesa’, enquanto que para a abobrinha ‘italiana’ foram determinados: número médio de frutos por plantas, tamanho médio do fruto, diâmetro médio do fruto, peso do maior fruto, e peso da matéria fresca e seca. Estes dados de produção foram submetidos à análise de variância através do Teste de LSD (least significant difference test – teste da diferença mínima significativa) de Fisher aos níveis de 1 ou 5% de probabilidade, observando-se diferenças significativas entre os tratamentos. A contagem de E. coli tanto na água residuária doméstica tratada por radiação solar, encontram-se dentro do padrão estabelecido respectivamente pela World Health Organization - WHO (1989). Porém as análises dos vegetais demonstraram que em alguns tratamentos houve contaminação acima do recomendado pela legislação da Agência Nacional de Vigilância Sanitária - ANVISA n. 12 da, de 02 de janeiro de 2001, demonstrando a necessidade de verificar outras possíveis causas de contaminação ou reativação dos microrganismos. Logo conclui-se que, a aplicação de água residuária doméstica tratada por radiação solar é uma prática válida, pois em todas as porcentagens de ARD-TRS na lâmina apresentaram aumento na produção, sendo uma alternativa viável para os produtores, pois não representa risco sanitário para o irrigante.
|
100 |
Biogenní aminy v pivu / Biogenic amines in beerČiháková, Dagmar January 2016 (has links)
This thesis deals with the technological process of brewing beer, describes the raw materials needed for its production, and points out the useful and harmful substances contained in beer as biogenic amines (BA). Furthermore, there are described the issues of biogenic amines in food and primarily in beer, which is a histamine, putrescine, cadaverine, tyramine and tryptamine. In the practical section BA was determined in lager bottom-fermented beers from local microbreweries and large industrial breweries.
Beer is according to legislation considered as a safe food containing a variety of healthful nutrients such as B vitamins, proteins, carbohydrates, minerals, soluble fiber and polyphenolic merged, which have anticarcinogenic, antioxidant and antimicrobial effects. On the other hand, in beer we can find harmful substances such as alcohol, heavy metals, N-nitrosamines, aromatic hydrocarbons, polychlorinated biphenyls, nitrates and biogenic amines.
In the second part of the research are summarized the issues of BA in certain foods and beverages, their chemical structure, the way how they are created and their negative effects on the human body. BA are natural, biologically active substances that are essential for the human organism. Their excessive amount in beer is toxic for the human organism. Ethanol contained in the beer decreases the activity of the enzyme monoamine oxidase, and this leads to reduced degradation of BA. Intoxication of BA can cause headaches, vomiting, hypertension, allergic reactions, rashes and even loss of consciousness, therefore, should be the content of these substances monitored.
In the practical part of this theses the samples of bottom-fermented beers were analyzed. The first group of samples included unfiltred and unpsaterized beers from microbreweries. In the second group there were filtered and pasteurized beers from large breweries. HPLC determined BA in beer (histamine, putrescine, cadaverine, tyramine and tryptamine). The resulting values indicate that the domestic beers contain biogenic amines in very small concentrations, thus satisfy the legislative standarts. The results were also compared between the two groups of samples. These samples showed that the beer from microbreweries is not contaminated as originally was expected. It shows good technological processes in the manufacture of beer in such small devices.
|
Page generated in 0.0451 seconds