<p>Osobe kojima su transplantirani organi imaju povećan rizik pojave malignih oboljenja, među kojima dominiraju maligni tumori kože. Smatra se da je osnovni razlog primena imunosupresivne terapije, ali jo&scaron; nije sasvim jasan mehanizam i nivo dejstva različitih imunosupresiva. Važan uticaj na nastanak većine malignih tumora kože ima ultraljubičasto (UV) zračenje koje izaziva pojačano starenje kože u vidu histolo&scaron;ki prepoznatljivog fotoo&scaron;tećenja, sa odlikama razvoja elastoze i limfocitne infiltracije. U na&scaron;oj zemlji do sada nisu sprovođena istraživanja rizika pojave maligniteta kože kod transplantiranih pacijenata, ne postoje podaci o njihovoj incidenci, uticaju imunosupresivne terapije i drugim potencijalnim faktorima rizika. U dostupnoj literaturi nema objavljenih radova iz oblasti analize histolo&scaron;kog fotoo&scaron;tećenja kože kod osoba na imunosupresivnoj terapiji. Ciljevi ove studije preseka bili su utvrđivanje učestalosti, vrste i lokalizacije premalignih i malignih lezija kože kod pacijenata nakon transplantacije bubrega, povezanosti njihove pojave sa dužinom, vrstom i režimom primene imunosupresivne terapije i sa histolo&scaron;ki verifikovanim fotoo&scaron;tećenjem perilezionalne kože. U studiju je uključeno 66 pacijenata kojima je transplantiran bubreg (primaoci organskog transplantata &ndash; POT). Relevantni podaci su prikupljeni putem upitnika i iz medicinske dokumentacije, kliničko-dermoskopskim pregledom kože uočene suspektne lezije su bioptirane u cilju postavljanja dijagnoze i utvrđivanja histolo&scaron;kih parametara fotoo&scaron;tećenja, a u studiju su uključeni i maligni tumori kože POT ispitanika uklonjeni u periodu od prethodnih 5 godina ali nakon transplantacije. Radi komparacije prisutnih faktora rizika i stepena fotoo&scaron;tećenja kože sa op&scaron;tom populacijom formirana je kontrolna grupa (KG) ispitanika kojima je prethodno bioptirana koža, bez oboljenja bubrega i bez imunosupresije, slična po polu i životnoj dobi sa onim POT ispitanicima kojima je urađena biopsija. Za svaku leziju iz POT grupe obezbeđene su po 2 lezije iz KG, tako da je pojedinim ispitanicima POT grupe analizirano vi&scaron;e lezija, dok je u KG 1 ispitanik &ndash; 1 lezija. Osnovno oboljenje bubrega do započinjanja dijalize kod ispitanika POT grupe prosečno je trajalo 7,67 godina, u strukturi oboljenja bubrega dominirao je hronični glomerulonefritis sa 31,8%, a ispitanici su na dijalizi bili prosečno 4,54 godine. Prosečna životna dob ispitanika u momentu transplantacije iznosila je 42,5 godina, 60,6% imalo je isključivo kadaveričnu transplantaciju, a prosečno trajanje jatrogene imunosupresije iznosilo je 4,89 god. U POT grupi bioptirane su 33 lezije, među kojima su od značaja za studiju bile 2 (6,1%) aktinične keratoze (AK), 3 (9,1%) displastična nevusa (DN), 1 (3,0%) melanom (MM), 3 (9,1%) skvamocelularna karcinoma (SCK) i 6 (18,2%) bazocelularnih karcinoma (BCK). U POT grupi učestalost MM bila je 1,5%, učestalost SCK 4,5%, učestalost BCK 9,1%, dok je utvrđeni relativan rizik pojave MM u POT populaciji 227 puta veći, BCK 316 puta veći, a SCK 805 puta veći nego u op&scaron;toj populaciji. Relativan rizik nastanka AK i DN nije određen zbog izostanka zvanične registracije u op&scaron;toj populaciji. POT grupa i KG nisu se statistički značajno razlikovale po Ficpatrikovom fototipu kože, profesionalnoj izloženosti UV zračenju, upotrebi solarijuma, broju solarnih opekotina, ličnoj anamnezi malignih tumora kože i konzumiranju cigareta. Pripadnici KG su se značajno vi&scaron;e rekreativno izlagali UV zračenju, če&scaron;će koristili sredstva za za&scaron;titu od sunčevog zračenja, če&scaron;će imali bliske srodnike sa malignim tumorima kože, če&scaron;će konzumirali alkohol, značajno veći broj ispitanika KG imao je pregled kompletne kože i informaciju o merama prevencije od strane lekara, dok 50% ispitanika POT grupe nije znalo da su pod povećanim rizikom pojave maligniteta kože. U stepenu elastoze među grupama nije postojala statistički značajna razlika, dok je limfocitna infiltracija bila marginalno izrazitija u POT grupi bez obzira na vrstu lezije. U POT grupi utvrđena je statistički značajna povezanost prisustva malignog tumora sa većim stepenom perilezionalne limfocitne infiltracije i elastoze. U KG utvrđena je statistički značajna povezanost prisustva malignog tumora sa većim stepenom limfocitne infiltracije, dok nije bilo statistički značajne razlike u stepenu perilezionalne elastoze. U studiji je utvrđeno da osobe nakon transplantacije bubrega imaju statistički značajno veći rizik nastanka BCK, SCK i MM kože u odnosu na op&scaron;tu populaciju, sa najče&scaron;ćom lokalizacijom ovih tumora u predelu glave. Dužina primene imunosupresivne terapije uop&scaron;teno nije statistički značajno uticala na pojavu premalignih i malignih tumora kože, ali je kumulativna doza pojedinih imunosupresiva poput ciklosporina i azatioprina imala statistički značajan uticaj na pojavu premalignih i malignih lezija kože. Dužina imunosupresije je statistički značajno uticala na stepen elastoze, ali je imala marginalan uticaj na stepen perilezionalne limfocitne infiltracije.</p> / <p>Organ transplant recipients are at an increased risk of developing malignancies, with the predominance of malignant skin tumors. The main cause is considered to be the administration of immunosuppressive therapy, but the mechanism and effect levels of different immunosuppressive agents are still not completely clear. Ultraviolet (UV) rays also influence the development of malignant skin tumors, causing increased skin aging with histologically recognisable photo damage, with its hallmark being development of elastosis and lymphocytic infiltration. No research on the topic of risks of malignant skin tumors in transplant patients has been done in our country, there is no data on their incidence, or on the effects of immunosuppressive agents and other potential risk factors. There are also no published studies in the field of hystological photo damage analysis in patients on immunosuppressive therapy. The aims of this study were to establish the rates of occurance, types and localisation of premalignant and malignant skin lesions in kidney transplant recipients (KTR) and to associate their advent with the length, type and regimen of immunosuppressive therapy. A total of 66 KTR patients were enrolled in the study. Relevant information was gathered through a specially constructed questionnaire and from the medical records, followed by combined clinical and dermoscopic skin examination to detect suspicious lesions which were biopsied in order to determine the histopathologic diagnosis of the lesion and perilesional degree of photo damage. The study also encompassed malignant skin tumors of KTR patients that have been removed in the last 5 years, but after the transplantation. For the sake of comparison of the risk factors and the levels of photo damage with the general population, an age and sex - matched control group (CG) of patients with previous skin biopsy but without kidney disease and immunosuppression was formed. For each lesion from KTR group, 2 lesions from CG were provided, meaning that some KTR patients had several lesions analysed, whereas in the CG only 1 lesion per patient was analyzed. The average duration of underlying kidney diseases in KTR was 7,67 years, the most frequent being chronic glomerulonephritis (31,8%), and an average duration of dialysis was 4,54 years. The mean age at transplantation was 42,5 years, with 60,6% of the KTR having exclusively cadaveric graft. The mean duration of the iatrogenic immunosuppression was 4,89 years. In the KTR group a total of 33 lesions were biopsied, 2 of which were actinic keratoses (AK) (6,1%), 3 were dysplastic nevi (DN) (9,1%), 1 melanoma (MM) (3,0%), 3 squamous cell carcinomas (SCC) (9,1%) and 6 basal cell carcinomas (BCC) (18,2%). The estimated frequency of MM was 1,5%, SCC 4,5%, BCC 9,1%, and the estimated relative risk of MM in KTR being 227, BCC 316, and SCC 805 times higher compared to the general population. The relative risk of AK and DN development could not have been estimated as there are no official records in the general population. The KTR and CG were not significantly different judging by the Fitzpatrick skin phototype, occupational UV exposure, sunbed usage, personal history of skin cancers, or smoking. The controls were recreationally more exposed to UV rays, used sun protective measures more frequently, had more relatives with skin cancers and consumed alcohol more frequently. A significantly greater number of controls had had complete skin examination and protective measures counceling by the doctor, while 50% of KTR patients did not even know that they were at an increased risk of malignant skin tumor development. There was no significant difference in elastosis levels among the groups, whereas the lymphocitic infiltration was only marginally greater in the KTR group. A significant association between the level of perilesional photodamage and developement of malignant tumors was estimated for the KTR group, whereas in the CG only the perilesional lymphocitic infiltration was strongly associated to malignant lesions. The study results suggest that KTR patients have a significantly higher risk of BCC, SCC and MM development in comparison with the general population, the most common localisation being in the head region. The duration of the immunosuppressive therapy had no significant effect on the premalignant and malignant tumors development, whereas the cummulative dose of certain immunosuppressives (such as cyclosporine and azathioprine) affected the development notably. The duration of immunosuppression statistically influenced the elastosis levels, but had only a marginal influence on the perilesional lymphocitic infiltration levels.</p>

HPLC has been used and can quickly determine several ions simultaneously. The method of determination described for transition metals [Cr(III), Fe(III), Ni(II), Co(II), Cu(II), Zn(II), Cd(II), Mn(II)] and [Ca(II), Pb(II)] using HPLC with UV-VIS detection is better than the PAR complexation method commonly used. The effects of both eluent pH and detector wavelength were investigated. Results from using different pHs and wavelengths, optional analytical conditions for the separation of [Ni(II), Co(II), Cu(II)], [Cr(III), Fe(III), Ca(II), Ni(II), Cu(II)], and [Ca(II), Zn(II), Pb(II)] in one injection, respectively, are described. The influence of adding different concentrations of Na_2EDTA solvent to the sample is shown. Detection limits, linear range, and the comparisons between this study and a post-column PAR method are given.

Cette thèse présente des reconstructions de l'irradiance totale et spectrale durant les 400 dernières années à l'aide des modèles pour l'irradiance totale et l'irradiance spectrale dans l'ultraviolet développés à l'Université de Montréal. Tous deux sont basés sur la simulation de l'émergence, de la fragmentation et de l'érosion des taches solaires, qui permet d'obtenir une distribution de l'aire des taches sombres et des facules brillantes en fonction du temps. Ces deux composantes sont principalement responsables de la variation de l'irradiance sur l'échelle de temps de la décennie, qui peut être calculée en sommant leur émissivité à celle de la photosphère inactive. La version améliorée du modèle d'irradiance solaire spectrale MOCASSIM inclut une extension de son domaine spectral entre 150 et 400 nm ainsi que de son domaine temporel, débutant originalement en 1874 et couvrant maintenant la période débutant en 1610 jusqu'au présent. Cela permet de reconstruire le spectre ultraviolet durant le minimum de Maunder et de le comparer à celui du minimum de 2009. Les conclusions tirées de cette étude spécifient que l'émissivité dans l'ultraviolet était plus élevée en 2009 que durant le minimum de Maunder, que le niveau de base de la photosphère non magnétisée contribuait pour environ les deux tiers de cette différence et que les structures magnétiques restantes étaient responsables pour le tiers restant. Le modèle d'irradiance totale a vu son domaine temporel étendu sur la même période et une composante représentant le réseau magnétique de façon réaliste y a été ajoutée. Il a été démontré que les observations des 30 dernières années ne sont bien reproduites qu'en incluant la composante du Soleil non magnétisé variable à long terme. Le processus d'optimisation des paramètres libres du modèle a été effectué en minimisant le carré de la somme de l'écart journalier entre les résultats des calculs et les données observées. Les trois composites disponibles, soit celui du PMOD (Physikalisch Meteorologisches Observatorium Davos), d'ACRIM (ACtive Radiometer Irradiance Monitor) et du IRMB (Institut Royal Météorologique de Belgique), ne sont pas en accord entre eux, en particulier au niveau des minima du cycle d'activité, et le modèle permet seulement de reproduire celui du PMOD avec exactitude lorsque la composante variable à long terme est proportionnelle au flux radio à 10.7 cm. Toutefois, en utilisant des polynômes de Lagrange pour représenter la variation du Soleil inactif, l'accord est amélioré pour les trois composites durant les minima, bien que les relations entre le niveau minimal de l'irradiance et la longueur du cycle précédent varient d'un cas à l'autre. Les résultats obtenus avec le modèle d'irradiance spectrale ont été utilisés dans une étude d'intercomparaison de la réponse de la photochimie stratosphérique à différentes représentations du spectre solaire. Les simulations en mode transitoire d'une durée de 10 jours ont été effectuées avec un spectre solaire constant correspondant soit à une période d'activité minimale ou à une période d'activité maximale. Ceci a permis d'évaluer la réponse de la concentration d'ozone à la variabilité solaire au cours d'un cycle et la différence entre deux minima. En plus de ceux de MOCASSIM, les spectres produits par deux modèles ont été utilisés (NRLSSI et MGNM) ainsi que les données de SIM et SOLSTICE/SORCE. La variabilité spectrale de chacun a été extraite et multipliée à un spectre de base représentant le minimum d'activité afin de simuler le spectre au maximum d'activité. Cela a été effectué dans le but d'isoler l'effet de la variabilité seule et d'exclure celui de la valeur absolue du spectre. La variabilité spectrale d'amplitude relativement élevée des observations de SORCE n'a pas provoqué l'inversion de la réponse de l'ozone à hautes altitudes obtenues par d'autres études, ce qui peut être expliqué par la nature même du modèle utilisé ainsi que par sa limite supérieure en altitude. Finalement, la réponse de l'ozone semble être à peu près proportionnelle à la variabilité de l'intégrale du flux pour lambda<241 nm. La comparaison des concentrations d'ozone obtenues avec les spectres originaux au minimum d'activité démontre que leur différence est du même ordre de grandeur que la variabilité entre le minimum et le maximum d'un cycle typique. Le problème du choix de la reconstruction de l'irradiance à utiliser pour les simulations climatiques dans le passé demeure non résolu. / This thesis presents reconstructions of the total and spectral solar irradiance for the last 400 years produced with the improved versions of the models for total and spectral solar irradiance in the ultraviolet developed at Université de Montréal. Both are based on the simulation of sunspot emergence, fragmentation and erosion, which produces a time-evolving area distribution of dark spots and bright faculae. These two components are the main drivers of irradiance decadal variations and this quantity can be calculated by summing their emissivity to that of the quiet photosphere. The improved version of the model for spectral irradiance, MOCASSIM, includes an extension of its spectral domain between 150 and 400 nm and of its temporal domain, with reconstructions now starting in 1610 instead of 1874. This allows to reconstruct the UV spectrum during the Maunder minimum and to compare it to the spectrum during the minimum of 2009. The conclusions of this study state that the Sun was slightly brighter during the recent minimum and that the slowly-varying quiet Sun contribution accounts for about two thirds of this difference, whereas remnant magnetic structure decay products account for the other third. The model for total irradiance was also extended further in the past, with reconstructions now starting in 1610. Also, a realistic network component was added. This was expected to help reproduce the observations spanning the last 30 years, especially the varying level of the irradiance during minimum activity. It was shown that the inclusion of a slowly-varying quiet Sun component was necessary to account for the observations. The free parameters of the model were adjusted by minimizing the sum of the daily squared difference between the model's output and the observations. The three available composites, from the PMOD (Physikalisch Meteorologisches Observatorium Davos), ACRIM (ACtive Radiometer Irradiance Monitor) and IRMB (Institut Royal Météorologique de Belgique) teams, do not agree between them, especially considering the minima of the activity cycle. The only composite reproduced in a satisfactory manner by the model when the variable quiet Sun component is proportionnal to the radio flux at 10.7 cm is the PMOD composite. However, using Lagrange polynomials to represent this component helps improve the agreement at minimum activity for all composites, even though the relation between the irradiance during the minima and the length of the preceding cycle varies from one to another. The results obtained with MOCASSIM were used during an intercomparison study of the photochemical response in the stratosphere to different representations of the solar spectrum. Transient simulations of duration 10-days were performed with a constant solar spectrum corresponding to either a maximum or minimum activity period. This allowed to estimate the response in stratospheric ozone to the solar variability over a cycle or between two minima. The spectra obtained with MOCASSIM were used along with those from two other models, NRLSSI and MGNM, and the SIM and SOLSTICE/SORCE data. The spectral variability from each data set was multiplied to a common baseline spectrum to produce the high activity spectrum in order to isolate the effet of the variability only, and to exclude the effect of the absolute spectral calibration. The high spectral variability of the SORCE data in the UV did not induce a negative response in ozone at high altitude, as obtained by various other studies. This is explained by the nature of the model and by its limited vertical extent. Finally, the ozone response is approximately proportional to the integrated UV flux below 241 nm. The comparison of the ozone concentration at minimum activity obtained with the original spectra shows that the difference is of the same magnitude as the response over a solar cycle. The problem of choosing a solar spectral irradiance reconstruction for climatic simulations in the past remains unsolved.

The aim of the diploma thesis was to find optimal conditions of high pressure liquid chromatography for the detection and quantification of two common nucleotides, namely adenosine diphosphate and adenosine triphosphate, as well as to perform an analysis of these in real life samples of citrus fruits and plant extracts. Further aim of the project was to determine the limits of detection and quantification of adenosine diphosphate and adenosine triphosphate under the optimized conditions and using these to compare the sensitivity of given detectors. To achieve this HPLC-UV, capillary HPLC-DAD and HPLC-MS apparatus were used. With the help of HPLC with UV detection and capillary HPLC with diode array detector, the calibration curves of the mixture of analytes were measured and the limits of detection as well as quantification of adenosine diphosphate and adenosine triphosphate were determined. Separation of the analytes up to the base line using HPLC-UV and capillary HPLC-DAD was achieved under the conditions of ion pairing chromatography. Column C18 was chosen as an appropriate column. The mobile phase included phosphate buffer, acetonitrile and tetrabutylammonium bisulphate as an ion pairing reagent. The separation was performed with gradient elution. Conditions for analysis using LC-MS were...

A luz ultravioleta (UV) bloqueia a replicação e transcrição devido à formação de lesões que distorcem o DNA. Descobrimos que a depleção da quinase ATR promove a indução precoce de apoptose após irradiação com luz UVB em fibroblastos humanos imortalizados com SV40 e que mesmo células proficientes em reparo de DNA e síntese translesão foram incapazes de alcançar a mitose após depleção de ATR. Essa quinase também representa um alvo promissor para sensibilizar tumores com mutações em p53 ao quimioterápico cisplatina e ao indutor de estresse oxidativo cloroquina. Além do bloqueio da replicação, danos no DNA bloqueiam a síntese de RNA. Utilizamos sequenciamento para mapear RNA nascentes e analisar a recuperação da transcrição em escala genômica. Genes mais longos são mais inibidos por luz UV, mas o nível de expressão gênica não contribui para a recuperação da transcrição. Além disso, o reparo de DNA é similar entre genes com recuperação da transcrição distinta e outras regulações, além da remoção de lesões no DNA, devem existir para que a síntese de RNA recomece. / Ultraviolet (UV) light stalls replication and transcription due to the formation of lesions that distort DNA. We found that ATR silencing promotes early induction of apoptosis after UVB light in human fibroblasts immortalized with SV40 and even cells proficient in DNA repair and translesion synthesis were unable to reach mitosis after ATR depletion. This kinase is also a promising target for sensitizing tumors with p53 mutations to chemotherapeutic that block replication, such as cisplatin, and the oxidative stress inducer chloroquine. In addition to blocking the replication, DNA damage arrest the synthesis of RNA. We used next-generation sequencing to map and analyze the nascent RNA transcription recovery genome-wide. We confirmed that longer genes are more inhibited following UV light, however, the level of gene expression does not contribute to the recovery of transcription. Moreover, DNA repair is similar among genes with different recovery of transcription and further regulation, besides DNA damage removal, must exist to promote resumption of RNA synthesis.

Em decorrência da destruição da camada de ozônio pela poluição, a incidência da radiação ultravioleta sobre a Terra tem aumentado, e consequentemente, o número de casos de câncer de pele tem elevado cada vez mais. Diversos estudos têm demonstrado que os danos causados pela radiação solar à pele são causados frequentemente pela geração de radicais livres e ativação de mediadores do processo inflamatório. Estudos têm concluído que os filtros solares são capazes de penetrarem na pele e agirem como fontes de formação de espécies reativas de oxigênio (EROs) quando submetidos à radiação ultravioleta, o que leva a uma preocupação de que as moléculas fotoprotetoras podem ser geradoras de EROs ao invés de prevenir a formação dessas espécies pelo bloqueio da radiação solar. Desta forma, o objetivo deste estudo foi avaliar os efeitos dos filtros solares 3- benzofenona (3-BZ), octilmetoxicinamato (OMC) e salicilato de octila (OS) na pele de camundongos sem pêlos submetida ou não à radiação UVB. Além disso, a retenção cutânea dos filtros solares foi avaliada in vitro utilizando pele de orelha de porco em células de difusão e in vivo em pele de camundongos sem pêlos. Os resultados de retenção cutânea in vitro demonstraram que a formulação gel creme promoveu maior retenção dos filtros solares na pele em comparação às formulações loção e creme. Além disso, a 3-BZ apresentou a maior retenção na pele quando comparadas as retenções dos filtros solares veiculados na mesma formulação. Todos os filtros solares penetraram na pele de camundongos sem pêlos após 1 hora da aplicação da formulação gel creme, o que garantiu a presença dos filtros solares na derme e epiderme no momento da exposição à radiação UVB. A formulação adicionada dos filtros solares preveniu em 76% a depleção de GSH induzida pela radiação UVB. Entretanto, o tratamento dos animais com a formulação contendo os filtros solares não foi capaz de impedir o aumento das atividades da metaloproteinase-9 e mieloperoxidases induzido pela radiação. Além disso, a utilização da formulação adicionada dos filtros solares em associação à exposição à radiação UVB provocou uma diminuição da atividade da enzima antioxidante superóxido dismutase presente na pele. Desta forma, considerando os parâmetros avaliados neste estudo, a formulação fotoprotetora parece não proteger a pele contra os danos causados pela radiação UVB quanto deveria. Além disso, estes filtros parecem ser instáveis frente à radiação o que comprometendo assim a eficácia e segurança dos mesmos. / Due to the destruction of the ozone layer by pollution, the incidence of ultraviolet radiation on Earth has enlarged and, consequently, the number of cases of skin cancer has increased even more. Several studies have shown that the damages caused by solar radiation to the skin are usually caused by free radical generation and activation of inflammatory mediators. Several studies have concluded that sunscreens are able to penetrate the skin and act as sources of formation of reactive oxygen species (ROS) under ultraviolet radiation exposition, leading, therefore, to the concern regarding the possibility of sunscreen molecules generate ROS instead of preventing the formation of these species by blocking sunlight. Thus, the aim of this study was to evaluate the effects of benzophenone-3 (3-BZ), octylmethoxycinnamate (OMC) and octyl salicylate (OS) sunscreens in the skin of hairless mice exposed or not to UVB radiation. Furthermore, the sunscreen skin retention was in vitro assessed using pig ear skin in diffusion cells and in vivo assessed using hairless mice. The results demonstrated that the cream gel rendered higher epidermal concentrations of the evaluated filters compared to the lotion and cream formulations. Comparing the skin retention amounts of each filter in the same formulation, 3-BZ showed higher skin retention ability than OMC and OS. In addition, all sunscreens penetrated the skin of hairless mice after 1 hour of the applied gel cream formulation, which guaranteed the presence of sunscreen in the dermis plus epidermis at the time of UVB exposure. The formulation of sunscreens prevented by 76% the GSH depletion induced by UVB radiation. However, the treatment of the animals with the sunscreens loaded-formulation was not able to inhibit the increase of metalloproteinase-9 and myeloperoxidase activities induced by radiation. Furthermore, the use of sunscreens loaded-formulation in combination with UVB radiation exposition caused the decrease in the amounts of the superoxide dismutase antioxidant enzyme present in skin. Thus, considering the parameters evaluated in this study, the sunscreens loaded-formulation does not seem to effectively protect skin against damages caused by UVB radiation as it was supposed to. Moreover, these filters seem to be unstable against the radiation and thus compromising their efficacy and safety.

Este trabalho apresenta resultados de ensaios de fissuramento sob tensão (FST) realizados em geomembranas de polietileno (PE) virgens e degradadas em laboratório. As geomembranas foram degradadas pela exposição à radiação ultravioleta, por envelhecimento térmico em estufa com circulação de ar, e pela compatibilidade química com soda cáustica e com vinhaça. Os resultados destes ensaios demonstram que os processos de degradação a que as geomembranas foram submetidas podem ser considerados catalisadores do fenômeno de FST, pois ocorreram reduções de resistência ao FST da ordem de 50 a 60%, com exceção para a amostra em compatibilidade química com vinhaça, que obteve aumento de 17% na resistência ao FST / This work presents results of stress cracking tests (SC) accomplished in virgin and degraded polyethylene (PE) geomembranes at laboratory. Geomembranes were degraded by exposition to ultraviolet radiation, by thermal aging in oven with circulation of air, and by chemical compatibility with sodium hydroxide and with leachate of alcohol production. The results of these tests demonstrate that the degradation processes of the geomembranes were submitted can be considered catalysts of the phenomenon of SC, because they happened resistance reductions to stress crack resistance of the order from 50 to 60%, with exception for the sample in chemical compatibility with leachate of alcohol production, that had an increase of 17% in the stress crack resistance

A remoção de microrganismos patogênicos através da desinfecção é uma necessidade para diminuir a incidência de doenças na população humana relacionadas com poluição fecal. A desinfecção sequencial tem grande potencial na remoção de microrganismos, quando comparada com a desinfecção convencional (um desinfetante). Neste trabalho buscou-se comparar a resistência de microrganismos indicadores de bactérias - E. coli e coliformes totais - e bactérias esporuladas - Clostridium perfringens quanto à desinfecção sequencial empregando cloro seguido de radiação ultravioleta e ozônio seguido de radiação ultravioleta; e à desinfecção convencional utilizando-se os mesmos desinfetantes aplicados individualmente em esgoto sanitário tratado previamente em reator UASB. Os ensaios foram realizados em batelada. As dosagens de cloro aplicadas foram de 10, 20 e 30 mg\'CL IND.2\'/L; de ozônio foram de 5,6; 11 e 16,5 mg\'O IND.3\'/L, ambos para os tempos de contato 10, 20 e 30 minutos. Na desinfecção sequencial com cloro foram aplicadas as doses de 1, 5 e 10 Wh/\'M POT.3\' de radiação UV; com ozônio, as doses de radiação foram variadas de 0,5 a 10 Wh/\'M POT.3\'. Na desinfecção sequencial de cloro-UV, foram removidos 2,5 e 5,2 log de C. perfringens e coliformes totais, respectivamente contra 1,5 e 4,2 log na desinfecção convencional para os mesmos microrganismos. Na desinfecção com cloro, a ordem decrescente de resistência foi: C. perfringens > coliformes totais > E. coli. Para ozônio seguido de UV, C. perfringens apresentou maior resistência e, em alguns ensaios, E. coli apresentou-se mais resistente que coliformes totais. A ação do ozônio mostrou-se notável para a melhoria da qualidade do esgoto tratado avaliada pela diminuição das concentrações de sólidos suspensos totais, sólidos totais, absorbância em comprimento de onda de 254 nm e da DQO, diferentemente do esgoto clorado no qual ocorreu o aumento nos valores destas variáveis físico-químicas. A ação da radiação ultravioleta foi potencializada quando aplicada sequencialmente ao cloro e ao ozônio. / The removal of pathogenic microorganisms through disinfection is a necessity to decrease the incidence of diseases in the human population related to fecal pollution. Sequential disinfection has a great potential on the removal of microorganisms when compared to conventional disinfection (single disinfectant). This work compared the resistance of indicators microorganisms of bacteria - E. coli and total coliforms - and spore-forming bacteria - Clostridium perfringens concerning the sequential and conventional disinfections. The sequential disinfection initially employed chlorine followed by ultraviolet radiation and ozone followed by ultraviolet radiation. The conventional disinfection utilized the same disinfectants individually applied in sanitary sewage previously treated in UASB reactor. The tests were made in batch. The chlorine dosages applied were 10, 20 and 30 mg\'CL IND.2\'/L; ozone were 5,6; 11 and 16,5 mg\'O IND.3\'/L, both for the contact times 10, 20 and 30 minutes. In the sequential disinfection with chlorine dosages of 1, 5 and 10 Wh/\'M POT.3\' of UV radiation were applied; with ozone, the dosages of radiation varied from 0,5 to 10 Wh/\'M POT.3\'. In the sequential disinfection with UV-chlorine were inactived 2,5 and 5,2 log of C. perfringens and total coliforms respectively, against 1,5 and 4,2 log in the conventional disinfection for the same microorganisms. In the chlorine disinfection, the decreasing resistance order was: C. perfringens > total coliforms > E. coli. In the ozone disinfection followed by UV, C. perfringens manifested more resistance and, in some assays, E. coli was more resistant than total coliforms. The action of ozone was outstanding for the improvement of treated sewage quality assessed by the decreasing of total suspended solids concentration, total solids absorbance at a wavelength of 254 nm and of DQO, differently from the chlorine sewage in which occurred an increase of the values of the physical-chemical variables. The ultraviolet radiation action was potentiated when sequentially applied to chlorine and to ozone.

A proposta desta pesquisa foi avaliar a aplicação do processo oxidativo avançado (POA), peróxido de hidrogênio (\'H IND.2\'O IND.2\') e radiação ultravioleta (UV), como pós-tratamento de um reator anaeróbio utilizado para tratar efluentes de branqueamento de indústrias de celulose kraft. O principal objetivo do pós-tratamento químico foi aumentar a biodegradabilidade e a remoção de compostos recalcitrantes nos efluentes. O tratamento biológico foi realizado por meio de reator anaeróbio horizontal de leito fixo (RAHLF), em escala de bancada, seguido pelo tratamento \'H IND.2\'O IND.2\'/UV dos efluentes. As doses do agente oxidante variaram de 50 a 500 mg \'H IND.2\'O IND.2\'/L e as aplicações de energia pela lâmpada de radiação ultravioleta foram variadas, principalmente, de 3,8 a 15,0 kWh por \'M POT.3\' de efluente tratado. Desta forma, amostras de efluentes foram coletadas de duas indústrias brasileiras de celulose kraft branqueada, originando respectivamente duas fases experimentais. Na primeira fase, o RAHLF apresentou boa estabilidade de operação, obtendo adequadas eficiências de remoção de DQO (61 ± 3%), COT (69 ± 9%), \'DBO IND.5\' (90 ± 5%) e AOX (55 ± 14%). Todavia, não ocorreu boa remoção dos compostos de absorbância na \'UV IND.254\'. Além disso, houve aumento de constituintes da lignina do afluente para o efluente do RAHLF. Por sua vez, o pós-tratamento com \'H IND.2\'O IND.2\'/UV no efluente anaeróbio proporcionou eficiência de remoção variada nos parâmetros DQO (0 a 11%), \'UV IND.254\' (16 a 35%), lignina (0 a 29%) e AOX (23 a 54%). Em relação a melhoria da biodegradabilidade, todas as dosagens de \'H IND.2\'O IND.2\' estudadas promoveram aumento na relação \'DBO IND.5\'/DQO. Para uma relação \'DBO IND.5\'/DQO média inicial igual a 0,09, correspondente ao efluente do RAHLF, o maior aumento obtido foi de 131% aplicando 500 mg \'H IND.2\'O IND.2\'/L e 7,5 kWh/\'M POT.3\'. O tratamento conjugado biológico e químico foi necessário para atingir ao padrão europeu de emissão de AOX (< 0,4 kg AOX por tonelada de polpa de celulose seca produzida). Na segunda fase, o RAHLF apresentou alguns problemas operacionais, tais como entupimento nas conexões e quebras do reator de vidro, pelo possível aumento da carga orgânica volumétrica aplicada presente nos efluentes coletados na segunda indústria de celulose. O pós-tratamento com \'H IND.2\'O IND.2\'/UV mostrou menor desempenho nessa fase experimental, o que pode ser explicado também pelo maior teor de matéria orgânica residual, lignina, alcalinidade e íons cloretos ainda remanescentes nos efluentes tratados biologicamente. Visando complementar os estudos, testes em reatores aeróbios nos efluentes do RAHLF, tratados e não tratados pelos processos \'H IND.2\'O IND.2\'/UV, foram avaliados. Os resultados demonstraram que os melhores resultados (menor tempo de aeração necessário para atingir a mesma concentração dos parâmetros avaliados) foram alcançados pelos reatores que receberam efluentes previamente tratados pelo POA. Uma avaliação simplificada do custo operacional associado com a aplicação do tratamento \'H IND.2\'O IND.2\'/UV, em escala plena, indicou um custo de R$ 1,87 por \'M POT.3\' de efluente tratado. / The purpose of this research was to assess the application of the advanced oxidation processes (AOP), hydrogen peroxide (\'H IND.2\'O IND.2\') and ultraviolet radiation (UV), as post-treatment for an anaerobic reactor used to treat bleaching effluents from kraft pulp mills. The main objective of the chemical post-treatment was to increase the biodegradability and remove recalcitrant compounds from the wastewater. The biological treatment was performed in a fixed bed anaerobic horizontal reactor (FBAHR), in bench scale, followed by \'H IND.2\'O IND.2\'/UV treatment of the effluents. The oxidizer dosage varied from 50 to 500 mg \'H IND.2\'O IND.2\'/L while the energy applied by the UV lamp ranged, mainly, from 3.8 to 15.0 kWh per \'M POT.3\' of treated effluent. This way, wastewater samples were collected from two brazilian bleached kraft pulp mills thus the results were reported as two different experimental phases. In the first phase the FBAHR showed good operational stability and reached the expected removal efficiencies for COD (61 ± 3%), TOC (69 ± 9%), \'BOD IND.5\' (90 ± 5%) and AOX (55 ± 14%). However, the anaerobic treatment did not provide good removal of compounds indicated by \'UV IND.254\' absorbency. Furthermore, there was an increase of lignin from the affluent to effluent of the FBAHR. In its turn the \'H IND.2\'O IND.2\'/UV post-treatment provided a wide range of removal depending upon the dosage: COD (0 to 11%), \'UV IND.254\' (16 to 35%), lignin (0 to 29%) and AOX (23 to 54%). Regarding to the improvement in biodegradability, all dosages of \'H IND.2\'O IND.2\' applied in this work promoted an increase in the \'BOD IND.5\'/COD ratio. For an average initial \'BOD IND.5\'/COD ratio equal to 0.09, which corresponds to the FBAHR effluent, the greatest increase was 131% with 500 mg \'H IND.2\'O IND.2\'/L and 7.5 kWh/\'M POT.3\'. It was necessary to couple the anaerobic and the oxidative treatment to reach the current European allowable AOX emission load (< 0.4 kg AOX per ton of produced dried cellulose pulp). During the second phase of the experiments, the FBAHR had operational problems as plugging of the tubes and cracking of the reactor wall that may be partially attributed to the higher organic load applied, as the effluents from the second mill were stronger. The AOP post-treatment also had lower performance during this experimental phase, which may be explained by the higher concentration of the organic matter, lignin, alkalinity and chloride ions, still present in the biologically treated effluents. To complete the experiments samples from effluents of the FBAHR and AOP process were submitted to aerobic assays. By tests done in aerobic reactors in the FBAHR effluents, treated and non-treated by the processes \'H IND.2\'O IND.2\'/UV, it was verified that the best results, shorter aeration time requirement to reach the same concentration of the evaluated parameters, were obtained from reactors that received previously treated by AOP effluents. A simplified evaluation of the operational cost associated with the use of the tested AOP, in full scale, indicated a cost of R$ 1.87 per \'M POT.3\' of treated effluent.

Estudaram-se soluções para o pós-tratamento de efluentes de reatores UASB e de lagoas de estabilização visando à utilização em irrigação de culturas agrícolas. Nesta aplicação, normalmente são desejáveis bons níveis de remoção de sólidos em suspensão e graus elevados de desinfecção, além da conservação dos principais nutrientes. No caso do efluente de reatores UASB em escala real, foram construídas unidades em escala piloto envolvendo sedimentação, filtração e radiação UV. No primeiro experimento, o efluente dos reatores UASB passou por filtro de areia pressurizado em alta taxa e por reator UV de fluxo contínuo. Nesta etapa a concentração de sólidos em suspensão (SST) no efluente dos reatores UASB teve média de 233 mg/L, devido a problemas operacionais, sendo que o filtro apresentou eficiência média de 60% de remoção de sólidos em suspensão. Porém, como o filtrado apresentou absorbância ainda elevada, média de 0,476 cm-¹, a desinfecção UV resultou ineficiente e a contagem de coliformes do efluente final incompatível com o uso agronômico pretendido. No segundo experimento, o efluente dos reatores UASB recebeu tratamento complementar passando por decantador de alta taxa e filtração em leito de manta geotêxtil, seguindo finalmente para a desinfecção UV. A concentração de SST no efluente dos reatores UASB, sanados os problemas operacionais da ETE teve valor médio de 82 mg/L. Com essa concentração afluente relativamente baixa, o decantador lamelar demonstrou-se pouco eficiente e apresentou efluente com SST médio de 67 mg/L. No entanto, foi bastante útil para conter picos de concentração de sólidos no efluente dos reatores UASB, protegendo a etapa posterior de filtração. No efluente do filtro de manta geotêxtil, o SST médio foi de apenas 7 mg/L., ABS (254nm) de 0,245 cm-1 e Turbidez de 11 UNT. A desinfecção do efluente por radiação ultravioleta com dose recebida de 2,44 W.h/m³, resultou satisfatória com média geométrica de 1,12x101 NMP/100mL de E coli. No caso do efluente de sistema de lagoas de estabilização em escala real, aplicou-se pós-tratamento em escala piloto composto de filtro de areia pressurizado de alta taxa seguido de desinfecção por hipoclorito de sódio. A concentração de SST no efluente da lagoa facultativa teve média de 117 mg/L, enquanto que a média no efluente do filtro foi de 87 mg/L. Para concentrações de cloro dosado de 2,9; 6,2 e 11,7 mg/L, as médias geométricas das densidades de E coli no efluente final resultaram 1,13x10² NMP/100mL, 1,01x101 NMP/100mL e valor não detectado pelo método, respectivamente. Concluiu-se que é possível aplicar pós-tratamentos relativamente simples aos efluentes de reatores UASB e de lagoas de estabilização, quando se deseja uso agronômico e as principais condições operacionais destas unidades puderam ser avaliadas. / It was studied the application of a simple and economical post-treatment of effluent from wastewater treatment plant for the purpose of use on irrigation of agricultural crops. The research was conducted in two different wastewater treatment plants, (1) WTP UASB reactors with two application of post-treatment: (1.1) Post treatment with a sand bed filter pressurized at high-rate followed by ultraviolet disinfection. In this step, the concentration of suspended solids (TSS) in the effluent from the UASB reactor was 233 mg/L, the filter had efficiencies of 60% removal of suspended solids in the effluent from the UASB reactor, however, was not an appropriate result for effective disinfection of the effluent in the ultraviolet reactor. Absorbance values reached an average of 0.476 cm-¹. (1.2) Post-treatment at a high rate clarifier and on geotextile bed filtration to apply the ultraviolet disinfection. The concentration of TSS in the UASB reactor effluent has an average value of 82 mg/L, the concentration of the same parameter in the effluent from the clarifier was 67 mg/L and effluent of the filter geotextile, 7 mg/L. The system removed 91% of TSS in the effluent of the UASB reactor. In this experiment there was obtained a post-treated effluent with ABS (254nm) of 0.245 cm-1 and a turbidity of 11 NTU. The disinfection of the effluent by ultraviolet radiation with a dose received of 2.44 W.h/m³, obtained satisfactory results with geometric mean of 1.12x101 NMP/100mL E coli. (2) WTP by stabilization ponds with post-treatment in a pressurized sand filter followed by highrate disinfection by sodium hypochlorite solution. A TSS concentration in the effluent from facultative pond had an averaged 117 mg/L, the concentration of the same parameter in the effluent of the filter was 87 mg/L. With application of 2.88 mgCl2/L resulted in 1.13x10² NMP/100mL E coli, for the application of 6.2 and 11.7 mg/L chlorine was obtained 1.01x101 NMP/100mL E coli and ND, respectively.