This work provides overview of creating of a simple driver for the BIOS flash memory by accessing the physical computer memory. Although, the BIOS is one of a system's core components, there is no standardized update mechanism approach. Purpose of thesis is to create module driver by taking advantage of existing interface subsystem MTD, to suggest and implement driver for one specific device to Linux kernel operating system. Also explains technique allowing write access to registers of the flash memory with utilization of configuration file.

Made available in DSpace on 2015-04-14T13:09:13Z (GMT). No. of bitstreams: 1 419311.pdf: 1361781 bytes, checksum: b2420e6628557cca585fc9b340850f47 (MD5) Previous issue date: 2008-03-27 / O presente estudo foi desenvolvido em uma ?rea elevada do Escudo Sul-Riograndense localizada entre os Munic?pios de S?o Jer?nimo e Bar?o do Triunfo e teve como objetivo descrever a composi??o, ciclos de atividade sazonal, padr?es alimentares e reprodutivos de uma taxocenose de escamados. O per?odo de amostragem ocorreu de abril de 2004 a abril de 2006, onde os escamados foram procurados ativamente na ?rea (PV) e recolhidos por colaboradores residentes (CR). Considerando os dois m?todos aplicados, foram amostradas tr?s esp?cies de Amphisbaenidae, seis esp?cies de lagartos (Anguidae (1), Gymnophtalmidae (1), Scincidae (1) e Teiidae (3)) e 24 esp?cies de serpentes (Colubridae (20), Elapidae (1), Lepthotyphlopidae (1) e Viperidae (2)), totalizando 33,7 % da fauna de escamados do Rio Grande do Sul. Para as duas esp?cies mais freq?entes de Amphisbaenidae, Amphisbaena munoai e Anops kingii foi observado um padr?o unimodal de distribui??o sazonal, dimorfismo sexual no comprimento rostro cloacal (CRC) (f?meas > machos, Teste-t p < 0,001) e um ciclo reprodutivo sazonal ocorrendo na primavera e ver?o. Ambas as esp?cies apresentaram diversas categorias alimentares na composi??o de suas dietas, entretanto t?rmites (Isoptera) parecem compor um elemento base. Dados reprodutivos foram analisados para as duas esp?cies mais freq?entes de lagartos, Cnemidophorus lacertoides e Cercosaura schreibersii, que apresentaram reprodu??o tipicamente sazonal ocorrendo na primavera e ver?o. Em ambas as esp?cies, f?meas maduras apresentaram CRC significativamente maiores que machos (Teste t; p < 0,001). Por outro lado, machos maduros de ambas as esp?cies apresentaram comprimento e largura da cabe?a (Ancova; p < 0,001) maiores do que f?meas. Foram capturadas 325 serpentes, sendo as mais freq?entes: Bothrops pubescens (27,69%), Philodryas patagoniensis (12,31%), Philodryas olfersii (12%) e Tantilla melanocephala (8,62%), que juntas corresponderam a 60,62% do total da amostra. Utilizando-se apenas as serpentes capturadas por PV, pode-se observar correla??o significativa entre a freq??ncia relativa de serpentes ativas/m?s e a temperatura (Anova, p < 0,001) e, de car?ter inverso, foi observada correla??o significativa (Anova, p < 0,001) entre a freq??ncia relativa de serpentes capturadas abrigadas/m?s e a temperatura. Foram obtidas informa??es sobre a dieta de 17 esp?cies e anf?bios anuros (incluindo girinos) foi o item alimentar mais utilizado. O per?odo reprodutivo foi marcadamente sazonal ocorrendo na primavera e ver?o. Analisando a dieta das esp?cies de serpentes foi observado o primeiro registro de ofiofagia para Echinanthera occipitalis (= Taeniophallus occipitalis), que ingeriu um exemplar de Tantilla melanocephala. Por ocasi?o dos trabalhos de campo foi redescoberta a esp?cies de anf?bio anuro Melanophryniscus pachyrhynus conhecida at? ent?o por apenas dois s?ntipos coletados no sul do Brasil a cerca de 100 anos atr?s. A esp?cie foi redescrita e teve sua distribui??o geogr?fica ampliada.

Made available in DSpace on 2014-12-17T14:10:23Z (GMT). No. of bitstreams: 1 DiegoMB_DISSERT_capa_ate_pag68.pdf: 4934333 bytes, checksum: f6bbf7a59936a1c62765b29338c9cb20 (MD5) Previous issue date: 2011-03-25 / It is estimated that the Brazilian karst areas sum about 200.000 km2. The caves, one of the main components of karst, are important windows into the biological studies on hypogean environments. In Rio Grande do Norte are known 563 caves, and 476 of them are in the municipalities of Bara?na, Felipe Guerra, Governador Dix-Sept Rosado, Apodi and Mossor?, the Western region of the State. However, like in the rest of the country, the cave fauna of the State is still poorly understood. This study used data from invertebrates harvested in 47 caves and aimed to analyze the effect of environmental change between the dry and rainy seasons in the communities of cave invertebrates, characterize these communities and evaluate the relationships between morphological and biotic variables of the caves and surroundings, and to define priority areas for conservation of cave environments of the study area from biotic parameters. Strong effects were found in the community structure of cave invertebrates due environmental changes between seasons, with values of total richness, abundance, diversity and ecological complexity significantly higher in the rainy season. It was possible to assess how the morphology of the cave and the external environment variables affect the biotic system, so that the variety of resources, forest cover in the vicinity, the area of the cave and its entrance were the variables that best explained the structure communities of cave invertebrates in the region. High values of total richness of invertebrates (36,62 ? 14,04 spp / cave) and troglomorphic species (61 species, mean 1,77 ? 2,34 spp / cave) were found and, given the biological relevance in the context of the area national and the imminent anthropogenic pressures existing, we defined four priority areas for actions aiming cave biodiversity conservation in the region. / Estima-se que as ?reas c?rsticas brasileiras perfa?am cerca de 200 mil km2. As cavernas, um dos principais componentes do relevo c?rstico, s?o uma importante janela para a realiza??o de estudos biol?gicos sobre os ambientes hip?geos. No Rio Grande do Norte s?o conhecidas 563 cavidades, sendo que 476 delas encontram-se nos munic?pios de Bara?na, Felipe Guerra, Governador Dix-Sept Rosado, Apodi e Mossor?, regi?o Oeste do Estado. No entanto, a exemplo do restante do pa?s, a fauna cavern?cola do RN ainda ? pobremente conhecida. O presente estudo utilizou dados de coletas de invertebrados realizadas em 47 cavernas e teve como objetivos analisar o efeito das altera??es ambientais entre as esta??es seca e chuvosa nas comunidades de invertebrados cavern?colas, caracterizar essas comunidades e avaliar as rela??es entre vari?veis bi?ticas e morfol?gicas das cavernas e do entorno, bem como definir ?reas priorit?rias para a conserva??o de ambientes cavern?colas da ?rea de estudo a partir de par?metros bi?ticos. Foram encontrados fortes efeitos sobre a estrutura das comunidades de invertebrados cavern?colas em fun??o das mudan?as ambientais entre as esta??es, com valores de riqueza total, abund?ncia, diversidade e complexidade ecol?gica significativamente maiores na esta??o chuvosa. Foi poss?vel avaliar como a morfologia da caverna e vari?veis do ambiente externo influenciam as vari?veis bi?ticas do sistema, de forma que a variedade de recursos, a cobertura florestal no entorno, a ?rea da caverna e de suas entradas foram as vari?veis que melhor explicaram a estrutura das comunidades de invertebrados cavern?colas da regi?o. Foram encontrados elevados valores de riqueza total de invertebrados (36,62 ? 14,04 spp/caverna) e de esp?cies trogl?bias (61 esp?cies, m?dia de 1,77 ? 2,34 spp/caverna) e, diante da relev?ncia biol?gica da ?rea no contexto nacional e das iminentes press?es antr?picas existentes, foram definidas quatro ?reas priorit?rias para a??es de conserva??o da biodiversidade cavern?cola regional.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T23:07:11Z No. of bitstreams: 1 IaponiraSalesDeOliveira_TESE.pdf: 7423751 bytes, checksum: d1f0076be8615e4ab0d4436b4bd0fb6a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-14T00:22:33Z (GMT) No. of bitstreams: 1 IaponiraSalesDeOliveira_TESE.pdf: 7423751 bytes, checksum: d1f0076be8615e4ab0d4436b4bd0fb6a (MD5) / Made available in DSpace on 2017-03-14T00:22:33Z (GMT). No. of bitstreams: 1 IaponiraSalesDeOliveira_TESE.pdf: 7423751 bytes, checksum: d1f0076be8615e4ab0d4436b4bd0fb6a (MD5) Previous issue date: 2016-06-30 / Historicamente, a agricultura praticada na regi?o semi?rida do nordeste brasileiro ? n?made, itinerante ou migrat?ria; os agricultores desmatam, queimam, fertilizam o solo, plantam por um curto per?odo e migram para outras ?reas, onde repetem a mesma pr?tica, al?m de utilizarem uma quantidade significativa de agroqu?micos para o combate de pragas. Esta atividade tem provocado perda significativa de qualidade de vida e da biodiversidade local. No contexto da biodiversidade, destacam-se os Anf?bios Anuros, que compreendem os sapos, r?s, pererecas e jias, s?o relevantes nas cadeias e teias ecol?gicas, especialmente por serem bioindicadores de qualidade ambiental e biocontroladores de popula??es de insetos, estabelecendo um controle natural de pragas em ?reas agr?colas. Apesar de suas import?ncias, nas duas ?ltimas d?cadas t?m ocorrido decl?nio e desaparecimento de algumas esp?cies de Anuros no Brasil e em todo o mundo, por seres sens?veis; uma vez que s?o sens?veis a mudan?as ambientais. A redu??o de esp?cies pode ser decorrente de a??es antr?picas relacionadas ? devasta??o de ?reas naturais para utiliza??o agr?cola, garimpos ou pastagens. Nesse contexto, inexistem estudos que abordem as intera??es e reconhecimento de comunidades agr?colas e os anf?bios anuros, em especial em regi?o semi?rida do nordeste brasileiro, a exemplo daquelas sob influ?ncia da Bacia Hidrogr?fica do Rio S?o Francisco, onde comunidades vivem da agricultura e pecu?ria como principais atividades econ?micas, utilizando a ?gua daquele rio para irriga??o. A regi?o de Itaparica e respectivos sistemas agr?colas constituem parte de um projeto de pesquisa amplo e binacional, Brasil ? Alemanha (INNOVATE Project), o qual tem por objetivo geral identificar os m?ltiplos usos da ?gua do reservat?rio e analisar as inova??es referentes ao manejo dos recursos aqu?ticos e terrestres, e de cujo subprojeto, SP-4 - Biodiversidade e Servi?os do Ecossistema, esta tese ? decorrente. Neste cen?rio e contexto, o objetivo geral desta tese foi registrar, descrever e analisar qualitativamente o conhecimento de comunidades locais sobre as esp?cies de anf?bios anuros e sua biologia, visando o reconhecimento destes como biocontroladores de insetos pragas nos sistemas agr?colas, em substitui??o aos agroqu?micos, a fim de promover a conserva??o dos anuros e melhorar a qualidade de vida dos agricultores locais, em prol da sustentabilidade. As comunidades estudadas, Petrol?ndia e Itacuruba, est?o situadas ?s margens do m?dio Rio S?o Francisco, Estado de Pernambuco, onde o trabalho de campo foi efetuado durante quatro excurs?es, duas a cada um dos munic?pios estudados, entre os meses de novembro/2012 a abril/2013. Foram entrevistados 369 agricultores, com idades entre 18 e 65 anos, todos do sexo masculino, sobre as pr?ticas agr?colas e biologia das esp?cies de anf?bios anuros. Para a identifica??o das esp?cies de anf?bios anuros, foram inicialmente realizados est?mulos visuais, com o aux?lio de fotografias de esp?cies comuns em ?reas de caatinga. Este m?todo serviu para nortear os entrevistados contextualmente, assegurando que as entrevistas fossem direcionadas ao mesmo objeto (esp?cies de anf?bios anuros), a fim de coletar dados etnobiol?gicos precisos. Posteriormente, as esp?cies de anf?bios anuros mais citadas nas entrevistas foram coletadas atrav?s de busca ativa ao longo das ?reas agr?colas e Caatinga circunvizinha (parte dos dados secund?rios do Innovate Project). Para caracterizar os locais de reprodu??o e desenvolvimento dos anf?bios anuros nas ?reas agr?colas, foram elaborados mapas orais, obtidos a partir de turn?s guiadas com os agricultores que citaram a exist?ncia de s?tios reprodutivos em suas ?reas de cultivo, os quais foram georreferenciados. Os agricultores reconheceram e nomearam oito etnoesp?cies, que correspondem a 13 esp?cies de anf?bios anuros, bem como seus principais locais de reprodu??o e desenvolvimento. A partir destas informa??es, foram elaborados dois mapas georreferenciados, relacionados principalmente aos locais de reprodu??o, os quais demonstram 13 s?tios de reprodu??o em Itacuruba e seis em Petrol?ndia/PE. As respostas dos agricultores tamb?m possibilitaram identificar os valores atribu?dos aos anf?bios nas ?reas agr?colas, por meio do conhecimento acerca dos seus h?bitos alimentares, ao citarem que os anf?bios comem principalmente insetos (65% dos agricultores de Petrol?ndia, n=238; 58% em Itacuruba, n=131), demonstrando conhecimento acerca da participa??o destes animais no equil?brio ambiental e poss?vel controle de pragas agr?colas. N?o se constataram diferen?as de concep??o local, quanto ? import?ncia dos anf?bios no controle de pragas, entre sistemas irrigados e n?o irrigados. Os agricultores de Petrol?ndia (83%, n=238) e de Itacuruba (78%, n=131) relataram ter identificado, por observa??es in loco, que os anf?bios se alimentam de pragas agr?colas locais, possibilitando inferir que s?o biocontroladores dessas pragas. Tamb?m foram bastante enf?ticos ao afirmarem que os anf?bios devem ser preservados (78%, n=238 em Petrol?ndia; 73%, n=131 em Itacuruba), principalmente por se alimentarem de insetos pragas, e por n?o constituir amea?a ?s comunidades agr?colas. Estas respostas possibilitaram a elabora??o de uma cartilha ilustrada, em literatura de Cordel, a qual ser? distribu?da e divulgada em escolas, cooperativas agr?colas e associa??es comunit?rias dos munic?pios estudados, como instrumento de populariza??o da Ci?ncia sobre a import?ncia dos anf?bios no biocontrole de pragas agr?colas, em substitui??o ao uso de Agroqu?micos. Entretanto, apesar de os agricultores locais destacarem a import?ncia dos anf?bios e de sua preserva??o para controle de insetos pragas, ainda n?o os aceitam como aliados no controle natural de pragas em substitui??o aos agroqu?micos. A populariza??o da Ci?ncia por meio do Cordel Ilustrado ? o primeiro passo em prol da sustentabilidade por meio de alternativas vi?veis e pr?ticas agr?colas sustent?veis, que visem ? conserva??o das esp?cies e das atividades locais. / Historically, agriculture in the semiarid region of northeastern Brazil is nomadic, traveling or migration ; farmers deforestation, burn, fertilize the soil, plant for a short period and migrate to other areas where repeat the same practice , and use significant amounts of pesticides for combating pests. This activity has caused significant loss of quality of life and local biodiversity. In the context of biodiversity, Amphibian Anura stand out, which include frogs, toads and jewelry, are relevant in chains and ecological webs, especially because they are bio-indicators of environmental quality and biocontrol of insect populations, establishing a natural control pests in agricultural areas. Despite their importance in the last two decades there has been decline and disappearance of some species of Anura in Brazil and around the world; since they are sensitive to environmental changes, reducing species may be due to human activities related to the devastation of natural areas for use of agricultural land, mining or pasture. In this context, there are no studies that address on the interactions and recognition of agricultural communities and amphibians, especially in semi-arid region of northeastern Brazil, like those under the influence of River Basin San Francisco, where communities living from agriculture and livestock as main economic activities using the water of this river for irrigation. Itaparica region and their agricultural systems are part of a broad research project and binational, Brazil - Germany (INNOVATE Project), which has the objective to identify the multiple reservoir water uses and analyze innovations for the management of resources water and land, and whose subproject, SP-4 - Biodiversity and Ecosystem Services, this thesis is integral. In this scenario and context, the general objective of this thesis was to record, describe and qualitatively analyze the knowledge of local communities on the species of amphibians and their biology, aimed at recognizing these as insect biocontrol pests in agricultural systems in place to agrochemicals, to promote the conservation of frogs and improve the quality of life of local farmers for sustainability. The communities studied, Petrol?ndia and Itacuruba, are situated to the average margins S?o Francisco River, State of Pernambuco, where the fieldwork was carried out for four trips, two to each of the cities studied, between the months from November / 2012 to April / 2013. A total of 369 male farmers were interviewed, whose ages ranged from 18 to 65 years old.They were asked about agricultural practices and biology of species of amphibians. For the identification of the species, they were initially made visual stimuli, with the help of photographs of common species in areas of caatinga. This method served to guide respondents contextually, ensuring that the interviews were directed to the same object (anurans) in order to collect accurate data ethnobiological. Later, the species of amphibians most mentioned in the interviews were collected by active search throughout the agricultural areas and Caatinga surrounding (part of secondary data from Project Innovate). To characterize the breeding sites and development of anurans in agricultural areas were prepared oral maps obtained from conducted tours to farmers who cited the existence of breeding sites in their areas of cultivation, which were georeferenced. Local farmers recognized and named eight ethnospecies, which correspond to 13 species of amphibians, as well as major sites of reproduction and development. From this information, we were prepared two georeferenced maps, mainly related to breeding sites, which show 13 breeding sites in Itacuruba six in Petrol?ndia / PE. The responses of farmers also possible to identify the values assigned to amphibians in the agricultural areas, through knowledge about their eating habits, to cite that amphibians eat mostly insects (65% of farmers Petrol?ndia, n = 238; 58% in Itacuruba, n = 131), demonstrating knowledge of the participation of these animals in the environmental balance and can control agricultural pests. Not found-site design differences, the importance of amphibians in pest control, between irrigated and non-irrigated systems. Farmers Petrol?ndia (83%, n = 238) and Itacuruba (78%, n = 131) reported having identified by observations on the spot that amphibians feed on local agricultural pests, making it possible to infer that are biocontrol of these pests. They were also quite emphatic in stating that amphibians should be preserved (78%, n = 238 in Petrol?ndia, 73%, n = 131 in Itacuruba), mainly feed on insect pests, and not pose a threat to agricultural communities. These responses allowed for the creation of an illustrated booklet in Cordel literature, which will be distributed and disseminated in schools, agricultural cooperatives and community associations of municipalities studied, such as the Science popularization instrument on the importance of amphibians in biocontrol of agricultural pests, replacing the use of agrochemicals. However, although local farmers stress the importance of Amphibian and its preservation to control insect pests, they do not accept them as allies in natural pest control to replace agrochemicals. The popularization of science through the Cordel Illustrated is the first step towards sustainability by sustainable agricultural and viable alternatives practices aimed at the conservation of species and local activities.

Diese Arbeit untersucht die Dauer von Bootvorgängen auf Linux-Systemen vom Einschalten des Rechners bis zur Benutzeranmeldung. Zeitintensive Abschnitte des Bootvorganges werden untersucht und Methoden zur Beschleunigung diskutiert. Dies beinhaltet eine Analyse verschiedener BIOS Versionen, der Kernel-Initialisierung und unterschiedliche Ansätze, Dienste zu starten. Es werden Startvorgänge eines gewöhnlichen Desktop-Systems mit einem eingebetteten VIA EPIA-ML-6000EA Mini-ITX System verglichen. / This research project evaluates startup times of the linux boot process from power-on until user login. Time consuming parts of the boot process are investigated and methods how to speed up the whole process are discussed. It includes an analysis and comparison of different BIOSes, the kernel startup sequence and different approaches to start user space services. This project also compares the startup times of everyday desktop systems with the EPIA-ML6000EA Mini-ITX board, an embedded x86-compatible system.

Made available in DSpace on 2014-12-17T15:03:17Z (GMT). No. of bitstreams: 1 FernandaLC.pdf: 619525 bytes, checksum: b172a729547f262e355961911646e833 (MD5) Previous issue date: 2007-03-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The technology of anaerobic reactors for sanitary wastewater treatment has been extensively developed in Brazil, and today it is practically consolidated. They present several advantages, such as low construction and operating costs, and low sludge production, the anaerobic reactors are an attractive alternative to minimize problematic lack of basic sanitation in urban areas, and also of the rural areas. The anaerobic filters have been widely used in Brazil. It produces an effluent with low concentration of organic matter and solids suspended, besides conserving the nutrients, therefore, it is good for use in irrigation, but the practice must be associated with knowledge of the pathogens presence. The main objective of this study was to evaluate the efficiency of anaerobic filters in removal faecal coliforms and helminth eggs, and to verify if the effluent can be used for agricultural purposes, according to the World Organization of Health (WHO, 1989). The protocol used to enumerate helminths eggs was the modified Bailenger method, (Ayres and Mara, 1996) recommended by WHO for evaluation of raw effluent and treated effluent. The membrane filtration method was utilized to determine the concentrations of faecal coliforms. Three different systems of sewer treatment composed by anaerobic filters were analyzed. The results, in a general analysis, showed that all the researched systems reached a larger removal than 93% to helminth eggs, resulting in an effluent with smaller average than 1 egg/L. One of these systems, Sistema RN, reached a larger removal than 99%, confirming the good performance of the anaerobic filters in removal helminths eggs. Even with low concentrations of eggs in the influent, the filters were capable to remove this parameter efficiently. About faecal coliforms, it was observed for all the researched systems an effluent with 106 CFU/100mL. The high concentrations to faecal coliforms in the effluent just allow reuse for restricted irrigation, in agreement with the guidelines of WHO. Although the researched systems have not removed faecal coliforms efficiently, the results indicated a good efficiency of the anaerobic filters in removal helminth eggs / A tecnologia de reatores anaer?bios para o tratamento de esgoto sanit?rio vem sendo extensivamente desenvolvida no Brasil, e hoje encontra-se praticamente consolidada. Apresentando diversas vantagens, como baixos custos de constru??o e opera??o, e baixa produ??o de lodo, os reatores anaer?bios s?o uma alternativa bastante atrativa para a mitiga??o dos problemas de saneamento b?sico urbano, e tamb?m das ?reas rurais. Os filtros anaer?bios v?m sendo bastante aplicados no Brasil. Sua utiliza??o produz um efluente com baixa concentra??o de mat?ria org?nica e s?lidos suspensos, al?m de conservar os nutrientes, sendo por isso muito bom para irriga??o com fins produtivos, desde que sejam resguardados os cuidados com a presen?a de organismos patog?nicos. Este trabalho teve por objetivo avaliar a efici?ncia de filtros anaer?bios na remo??o de coliformes fecais e ovos de helmintos, e verificar se os mesmos atendem ?s recomenda??es sanit?rias para reuso em irriga??o, segundo a Organiza??o Mundial de Sa?de - OMS (WHO, 1989). Para enumera??o dos ovos de helmintos foi utilizada a t?cnica de Bailenger modificada (Ayres e Mara, 1996), que deu origem ? metodologia atualmente recomendada pela OMS para avalia??o de ?guas residu?rias brutas e tratadas. Para determina??o de coliformes fecais foi utilizado o m?todo da membrana filtrante. Foram analisados tr?s diferentes sistemas de tratamento de esgoto compostos por filtros anaer?bios. Numa an?lise geral dos resultados, observou-se que todos os sistemas pesquisados atingiram efici?ncia maior que 93% para remo??o de ovos de helmintos, resultando em um efluente final com valor m?dio menor que 1 ovo/L. Um dos sistemas, o Sistema RN, alcan?ou uma remo??o maior que 99%, confirmando o bom desempenho dos filtros anaer?bios na remo??o de ovos de helmintos. Mesmo com baixas concentra??es de ovos no afluente, os filtros foram capazes de remover eficientemente este par?metro. Em rela??o ? contagem de coliformes fecais, foi observado, para todos os sistemas pesquisados um efluente final com cerca de 106 UFC/100mL. As altas concentra??es de coliformes fecais no efluente dos filtros permitem a reutiliza??o apenas para irriga??o restrita, de acordo com as diretrizes da OMS. Apesar dos sistemas pesquisados n?o removerem eficazmente coliformes fecais, os resultados encontrados no presente estudo indicaram uma boa efici?ncia dos filtros anaer?bios na remo??o de ovos de helmintos

Les métaux lourds et les radionucléides sont présents dans différents écosystèmes du monde à cause de contaminations naturelles ou des activités anthropiques. L’utilisation de micro-organismes pour restaurer ces écosystèmes pollués, processus connu sous le nom de bioremédiation, suscite beaucoup d’intérêt, spécialement aux pH proches de la neutralité. Les minéraux de fer qui encroûtent les bactéries neutrophiles du fer, notamment les Oxydes de Fer Biogéniques (BIOS en anglais), ont une structure très faiblement cristalline, qui en plus de leur grande surface et réactivité font d’eux d’excellents supports pour le piégeage de polluants inorganiques. Dans cette thèse nous avons étudié les différents mécanismes de piégeage de l’uranium uranium par la bactérie neutrophile Sphaerotilus natans, choisie comme modèle bactérien de micro-organismes du fer capables de filamenter en formant des gaines. S. natans peut croître sous forme de cellules individuelles ou formant des filaments. Ces derniers ont été utilisés pour étudier la biosorption d’U(VI) et sa sorption sur les BIOS. De plus, la sorption d’U(VI) sur les analogues abiotiques de ces minéraux de fer a été testée. Afin d’utiliser les filaments de S. natans pour piéger l’U(VI), il était nécessaire d’identifier les facteurs induisant la filamentation de S. natans. L’influence de l’oxygène a été établie en utilisant des techniques de biologie moléculaire et nos résultats ont démontré que tandis qu’en condition d’oxygène saturé elle croît sous forme de cellules individuelles, une diminution modérée d’oxygène à ~ 3 mg O2.L-1 la fait croître sous la forme désirée, des filaments de S. natans.Les BIOS attachés aux filaments de S. natans ainsi que ses analogues abiotiques ont été analysés pas XAS au seuil K du Fe. Les deux matériaux identifiés sont des phosphates de fer(III) amorphes avec une faible proportion de fer(II), qui présentent une réactivité élevée pour le piégeage de polluants inorganiques. L’EXAFS au seuil LIII de l’U a montré la même structure pour les couches O, tandis que celles P, Fe et C étaient différentes en fonction des sorbants. Une étude intégrée qui combine des techniques expérimentales avec des calculs de spéciation a permis de décrire les isothermes d’adsorption de l’U(VI) en utilisant un modèle de complexation de surface. Ces résultats suggèrent que les groupes phosphoryles et carboxyles sont les groupes fonctionnels principaux pour la biosorption d’U(VI) par des filaments de S. natans. Les résultats de cette thèse vont aider à comprendre les processus contrôlant l’immobilisation de l’U(VI), soit par la biosorption sur S. natans, la sorption sur les BIOS ou la sorption sur les phosphates de fer, et en conséquence le devenir de l’U en conditions neutres / Heavy metals and radionuclides are present in some ecosystems worldwide due to natural contaminations or anthropogenic activities. The use of microorganisms to restore those polluted ecosystems, a process known as bioremediation, is of increasing interest, especially under near-neutral pH conditions. Iron minerals encrusting neutrophilic iron-related bacteria, especially Bacteriogenic Iron Oxides (BIOS), have a poorly crystalline structure, which in addition to their large surface area and reactivity make them excellent scavengers for inorganic pollutants. In this PhD work we studied the different mechanisms of uranium scavenging by the neutrophilic bacterium Sphaerotilus natans, chosen as a model bacterium for iron-related sheath-forming filamentous microorganisms. S. natans can grow as single cells and filaments. The latter were used to investigate U(VI) biosorption and U(VI) sorption onto BIOS. In addition, uranium sorption onto the abiotic analogues of such iron minerals was assessed. In order to use S. natans filaments for U(VI) scavenging, it was necessary to identify factors inducing S. natans filamentation. The influence of oxygen was ascertained by using molecular biology techniques and our results revealed that while saturated oxygen conditions resulted in single cell growth, a moderate oxygen depletion to ~ 3 mg O2.L-1 led to the desired filamentous growth of S. natans. BIOS attached to S. natans filaments as well as the abiotic analogues were analysed by XAS at Fe K-edge. Both materials were identified as amorphous iron(III) phosphates with a small component of Fe(II), with a high reactivity towards scavenging of inorganic pollutants. In addition, EXAFS at the U LIII-edge revealed a common structure for the O shells, while those for P, Fe and C were different for each sorbent. An integrated approach combining experimental techniques and speciation calculations made it possible to describe U(VI) adsorption isotherms by using a surface complexation model. These results suggested the role of phosphoryl and carboxyl groups as the main functional groups involved in the U(VI) biosorption by S. natans. The results of this PhD work will help to better understand the processes governing U(VI) immobilization, either by S. natans biosorption, sorption onto BIOS or sorption onto iron phosphates, an thus the fate of uranium in near-neutral pH environments

Fluoride in drinking water can lead to a crippling disease called fluorosis. As there is no cure for fluorosis, prevention is the only means of controlling the disease and research into fluoride remediation is critical. This work begins by providing a new approach to assessing fluoride remediation strategies using a combination of groundwater chemistry, saturation indices, and multivariate statistics based on the results of a large groundwater survey performed in a fluoride-contaminated region of India. From the Indian groundwater study, it was noted that one technique recommended for defluoridation involved using hydrous ferric oxide (HFO) as a solid phase sorbent for fluoride. This prompted investigation of bacteriogenic iron oxides (BIOS), a biogenic form of HFO, as a means of approaching bioremediation of fluoride. Batch sorption experiments at ionic strengths ranging from 0.001 to 0.1 M KNO3 and time course kinetic studies with BIOS and synthetic HFO were conducted to ascertain total sorption capacities (ST), sorption constants (Ks), and orders of reaction (n), as well as forward (kf) and reverse (kr) rate constants. Microcosm titration experiments were also conducted with BIOS and HFO in natural spring water from a groundwater discharge zone to evaluate fluoride sorption under field conditions. This thesis contributes significant, new information regarding the interaction between fluoride and BIOS, advancing knowledge of fluoride remediation and covering new ground in the uncharted field of fluoride bioremediation.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-09-15T12:14:46Z No. of bitstreams: 1 2011 - Daiane Ouvernay Fernandes da Silva.pdf: 7586481 bytes, checksum: 5a97593f1df40687d3039aaf482f7a65 (MD5) / Made available in DSpace on 2016-09-15T12:14:46Z (GMT). No. of bitstreams: 1 2011 - Daiane Ouvernay Fernandes da Silva.pdf: 7586481 bytes, checksum: 5a97593f1df40687d3039aaf482f7a65 (MD5) Previous issue date: 2011-06-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study investigated the relationship between species of frogs, lizards, gradients environmental and insularity. We could detect a strong relationship between lizards in open habitats and anthropic as well as a strong influence of the area to the richness and abundance of lizards, rather than habitat heterogeneity. The community was the most diverse State Park Cunhambebe. The lizards of island environments of the Sepetiba Bay showed a strong relationship between abundance and area, supporting the hypothesis of Ecological Release. The species Cycloramphus sp., Thoropa miliaris, Hylodes asper, H. phyllodes, Phasmahyla cruzi and Scinax trapicheiroi are those with lower values of tolerance of distance from this physiognomy and sometimes only occur in this environment. / Neste estudo foram investigadas as rela??es entre esp?cies de anf?bios anuros, lagartos, gradientes ambientais e insularidade. Nota-se uma forte rela??o dos lagartos com ambientes abertos e antr?picos, bem como uma forte influ?ncia da ?rea para a riqueza e abund?ncia dos lagartos, mais que a heterogeneidade de habitats. A comunidade mais diversa foi a do Parque Estadual do Cunhambebe. Os lagartos de ambientes insulares da Ba?a de Sepetiba demonstraram forte rela??o entre abund?ncia e ?rea, corroborando com a hip?tese de Libera??o ecol?gica. As esp?cies Cycloramphus sp., Thoropa miliaris, Hylodes asper, H. phyllodes, Phasmahyla cruzi e Scinax trapicheiroi s?o as que possuem menores valores de toler?ncia de dist?ncia da cachoeira e, algumas vezes, s? ocorrem neste ambiente

Fluoride in drinking water can lead to a crippling disease called fluorosis. As there is no cure for fluorosis, prevention is the only means of controlling the disease and research into fluoride remediation is critical. This work begins by providing a new approach to assessing fluoride remediation strategies using a combination of groundwater chemistry, saturation indices, and multivariate statistics based on the results of a large groundwater survey performed in a fluoride-contaminated region of India. From the Indian groundwater study, it was noted that one technique recommended for defluoridation involved using hydrous ferric oxide (HFO) as a solid phase sorbent for fluoride. This prompted investigation of bacteriogenic iron oxides (BIOS), a biogenic form of HFO, as a means of approaching bioremediation of fluoride. Batch sorption experiments at ionic strengths ranging from 0.001 to 0.1 M KNO3 and time course kinetic studies with BIOS and synthetic HFO were conducted to ascertain total sorption capacities (ST), sorption constants (Ks), and orders of reaction (n), as well as forward (kf) and reverse (kr) rate constants. Microcosm titration experiments were also conducted with BIOS and HFO in natural spring water from a groundwater discharge zone to evaluate fluoride sorption under field conditions. This thesis contributes significant, new information regarding the interaction between fluoride and BIOS, advancing knowledge of fluoride remediation and covering new ground in the uncharted field of fluoride bioremediation.