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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Efeito do volume de terra no desenvolvimento das plantas de feijão e milho, na absorção do fósforo e no valor L (³²P) / Effect of soil volume on bean and corn plant growth, P uptake and L value (³²P).

Mendes, Fernanda Latanze 28 June 2006 (has links)
Estudou-se em casa-de-vegetação o efeito do volume de terra no desenvolvimento das plantas de feijão e milho, na absorção de fósforo pelas culturas e na determinação do P isotopicamente trocável (Valor L), em função do periódo de desenvolvimento dessas culturas e dois níveis de fertilidade do solo quanto ao fósforo. Avaliou-se também o efeito do P na planta proveniente da semente no cálculo do Valor L (L: valor L calculado sem descontar o P proveniente da semente e L (-Ps): valor L calculado descontando o P proveniente da semente). O estudo foi realizado com Latossolo Vermelho-amarelo em vasos plásticos contendo: 0,5; 1,0; 2,0; 4,0; 8,0; 12,0 e 18,0 L de terra; com e sem adubação de P (50 mg kg-1 terra de P) e colhendo as plantas em dois períodos: 30 e 50 dias após a germinação. O delineamento experimental foi inteiramente casualizado com 3 repetições no esquema fatorial 7x2x2. As variações nos períodos de colheita e níveis de fertilidade são representadas por: E1F1 (30 dias, sem adubação), E1F2 (30 dias, adubado), E2F1 (50 dias, sem adubação) e E2F2 (50 dias, adubado). A concentração de P nas plantas não foi um parâmetro adequado para estabelecer o estado nutricional das plantas e os vasos de 0,5 e 1,0 L tiveram desenvolvimento prejudicado e conseqüentemente no conteúdo de P, não sendo também adequados para determinação do valor L. Houve efeito do P na planta proveniente da semente no valor L para volumes de terra menor que 4,0 L para plantas de feijão e 8,0 L para plantas de milho. O volume de terra de 2,0 L é recomendado para estudos do valor L e L (-Ps) em plantas de feijão para as seguintes variáveis: E1F1, E1F2, E2F1 e em plantas de milho para E1F1 e E2F1. Para valor L e L (- Ps) em plantas de feijão para E2F2 e em plantas de milho para E1F2 e E2F2, recomenda-se o volume de terra de 4,0 L. A maior produção de massa seca e de conteúdo de P em plantas de feijão E1F2 foram obtidos com 12,0 L. Vasos com volume de terra de 13,0 L são os indicados para avaliação do desenvolvimento em plantas de milho E1F2 e E2F1. Com 14,0 L de terra obteve-se o maior conteúdo de P e massa seca em plantas de feijão E1F2 e conteúdo de P em plantas de milho E1F1. O volume de terra de 15,0 L é indicado para conteúdo de P em plantas de milho E1F2. Para a obtenção da máxima produção de massa seca em feijão em ambos os solos e épocas (E2F1 e E2F2) e milho no solo adubado e 50 dias (E2F2), assim como para conteúdo de P para feijão no E2F1 e E2F2 e milho E2F2, há necessidade de se usar vaso com volume de terra maior que 18,0 L. / The effect of soil volume on the growth of bean and corn crop, phosphorus uptake and isotopically exchangeable P (L value), as affected by the plant growing period and two soil P fertility level were studied in green house. The effect of seed derived P in the plant on the L value (L: L value calculated without discounting the seed derived P and L (- Ps): L value calculated discounting the seed derived P) was also evalueted. The study was carried out in plastic pots containing: 0.5; 1.0, 2.0, 4.0, 8.0, 12.0 and 18.0 L of Red Yellow Latosol, with and without P addition (50 mg kg-1 soil P) and harvesting the plants in two periods: 30 and 50 days after seeding. The experimental design was completely randomized with 3 replications in 7x2x2 factorial scheme. The variations in harvest period and soil P fertility level are presented as: E1F1 (30 days, without P application), E1F2 (30 days, with P), E2F1 (50 days, without P) and E2F2 (50 days, with P). The plant P concentration was not an adequate parameter for establishing the plant nutritional state. The plants of 0.5 and 1.0 L pots had their growth limited, which consequently affected the P content, therefore also not being adequate for the L value determination. There was effect of seed derived P on L value for soil volumes smaller than 4.0 L for bean plants, and 8.0 L for corn plants. The 2.0 L soil volume is recommended for L and L (-Ps) values studies with bean plants to the following variables: E1F1, E1F2, E2F1 and with corn plants to E1F1 and E2F1. For L and L (-Ps) values in beans plants to E2F2 and with corn plants to E1F2 and E2F2, the 4.0 L soil volume is recommended. The highest dry matter weight and P content in E1F2 bean plants were obtained with 12.0 L soil volume. Pots with 13.0 L soil are indicated for growth evaluation of E1F2 and E2F1 corn plants. The highest P content and dry matter weigh of E1F2 bean plants and E1F1 corn plants P content were obtained with 14.0 L soil volume. The 15.0 L soil volume is suggested for the P content study with E1F2 corn plants. For obtaining maximum dry matter yield of bean plants in both soils and growth periods (E2F1 and E2F2) and of corn in P fertilized soil harvesting at 50 days (E2F2), as well as for P content of E2F1 and E2F2 bean plants and E2F2 corn plants, pots with larger soil volume than 18.0 L should be used.
132

Self-Adaptive Honeypots Coercing and Assessing Attacker Behaviour / Paradigme de pot de miel adaptatif permettant d'étudier et d'évaluer le comportement et compétences des pirates informatiques

Wagener, Gérard 22 June 2011 (has links)
Les communautés de la sécurité informatique parlent de "pirates informatiques", mais en réalité, très peu est connu au sujet de leurs compétences. Durant la dernière décennie, le nombre d'attaques a augmenté de façon exponentielle et les pots de miels ont été alors introduits afin de recueillir des informations sur les attaquants. Ces pots de miel viennent en des saveurs différentes en fonction de leur potentiel d'interaction. Cette thèse abordera le paradigme des pots de miel adaptatifs pouvant changer leur comportement dans l’intention de tromper les attaquants en dévoilant le plus de renseignements possibles sur eux-mêmes. Plutôt que d'être autorisé simplement pour effectuer des attaques, les attaquants sont confrontés à des interférences stratégiques. En utilisant des critères mesurables, les compétences et les capacités de l'attaquant peuvent être évaluées par des pots de miel adaptatifs. Nous avons modélisé les interactions des attaquants. L'idée clé derrière la modélisation des interactions des attaquants élaborée dans cette thèse est d'utiliser la théorie des jeux pour définir la configuration d'un pot de miel adaptatif. Nous avons utilisé des mécanismes d'apprentissage par renforcement dans le but de trouver le meilleur comportement face à des attaquants. Un pot de miel adaptatif est capable d'adopter des stratégies comportementales au niveau de l’exécution de commandes par l'attaquant. Nos résultats expérimentaux montrent que ces stratégies dépendent des paramètres contextuels qui peuvent ainsi servir pour construire des pots de miel intelligents / Information security communities are always talking about "attackers" but in reality very little is known about their skills.In the last decade the number of attacks has increased exponentially and honeypots were introduced in order to gather information about attackers. Honeypots come in different flavors with respect to their interaction potential. Choosing the best trade-off between attacker freedom and honeypot restrictions is challenging. In this dissertation, we address the issue ofself-adaptive honeypots that can change their behavior and lure attackers into revealing as much information as possible about themselves. Rather than being allowed simply to carry out attacks, attackers are challenged by strategic interference from adaptive honeypots. The observation of the attackers' reactions is particularly interesting and, using derivedmeasurable criteria, the attacker's skills and capabilities can be assessed by the honeypot operator. We formally model the interactions of attackers with a compromised system. The key idea is to leverage game-theoretic concepts to define the configuration and reciprocal actions of high-interaction honeypots. We have also leveraged reinforcement learningmachine learning in order to arrive at the best behavior when facing attackers. Our experimental results show that behavioral strategies are dependent on contextual parameters and can serve as advanced building blocks forintelligent honeypots
133

Untersuchungen zur Vermehrbarkeit und zur Wachstumsregulierung von neu in den europäischen Markt einführbaren australischen Pflanzen

Marx, Peggy 16 April 2004 (has links)
Die vorliegende Arbeit zeigt die Möglichkeiten einer Kultur australischer Akazien als Topfpflanzen. Im ersten Teil werden in einer umfangreichen Literaturübersicht ökologische Standortbedingungen und bisherige nationale und internationale Veröffentlichungen über australische Akazien und zur Kultur weiterer australischer Pflanzen dargestellt. Untersuchungen zur generativen Vermehrung an 12 Akazienarten beinhalten verschiedene Saatgutvorbehandlungsmethoden: mechanische Beschädigung, Vorquellen, Behandlung mit konzentrierter Schwefelsäure, dem Seed Starter "Smoky Water" sowie die Behandlung mit hohen Temperaturen. Die mechanische Beschädigung des Saatgutes erzielt bei der Mehrzahl der untersuchten Akazienarten eine hohe Keimrate bei kurzer Keimdauer. Die Behandlung mit Seed Starter zeigt dagegen keine keimungsfördernde Wirkung. Praktische Versuche zur vegetativen Vermehrung durch Stecklinge beziehen sich auf unterschiedliche Stecklingsarten, Vermehrungstermine, Alter der Mutterpflanzen sowie verschiedene Stecklingsbehandlungen mit Bewurzelungshormonen und die Lagerung der Stecklinge. Es wird gezeigt, dass diese bisher problematische Vermehrungsmethode durch die Verwendung juvenilen Mutterpflanzenmaterials deutlich verbessert werden kann. Ferner konnte ein positiver Einfluss der Lagerung von Stecklingen auf die Bewurzelungsraten dargestellt werden. Vorteile bei der Bewurzelung und teilweise im weiteren Wachstum erzielte die Anwendung von IBS als Bewurzelungshormon. Versuche zur In-vitro-Kultur zeigen die Möglichkeit der In-vitro-Vermehrung und In-vitro-Bewurzelung der Akazienarten sowie die unproblematische Überführung in vivo für Acacia retinodes. Der Einfluss der Vermehrungsmethoden und -arten auf die weitere Entwicklung der Akazien wird im Teil der Wachstumssteuerungsmöglichkeiten untersucht. Es erfolgt die Darstellung der klimatischen Ansprüche und die Wirkung einiger kulturtechnischer Maßnahmen, beispielsweise die Anwendung von Hemmstoffen, Stutzen und Wurzelkürzen. Entscheidend für eine zeitige Blütenknospenbildung ist die Vermehrung über adultes Stecklingsmaterial. Die Kultur unter Zusatzlicht führt zu einem kompakten Habitus und einer verbesserten Blühinduktion. Die Blütenentwicklung kann durch das Absenken der Temperatur gefördert werden. Das Kürzen der Wurzeln beeinträchtigt die weitere Entwicklung der Pflanzen nicht. Durch Stutzen kann der Austrieb nicht gefördert werden; die Wirkung auf die Pflanzenhöhe erfolgt in Abhängigkeit vom Stutztermin. Abschließend werden Kulturschemata ausgewählter australischer Akazien als Blattpflanzen und blühende Topfpflanzen dargestellt. / This study was conducted to examine the suitability of the Australian acacias species for pot plant production. A comprehensive overall review of national and international literature was first carried out on ecological conditions of the habitat and cultivation of some Australian plants. The seed germination of 12 Acacia species was studied following a manual chipping treatment, exposure to hot water, concentrated sulphuric acid, the seed starter "Smoky water" and high temperature scarification. The manual chipping treatment resulted in a faster and improved germination rate. The seed treated with "Smoky water" showed no increase in germination rate. In-vitro-culture of acacia species was examined. In-vitro-propagation and in-vitro-rooting of acacia species was carried out. Acacia retinodes is adaptable to resettlement from in vitro to in vivo. Practical examinations of propagation included different types of cuttings, times of propagation, age of mother plants, treatment with root hormones and the storage of cuttings. The use of juvenile plant material for cuttings resulted in increased rooting percentages. Storage of cuttings had a positive influence on rooting rates. Treatment with indole butyric acid (IBA) promoted rooting and future plant growth. The portion of the study on growth manipulation examined the effects of using differing kinds and methods of propagation, different environmental conditions and technical manipulations such as growth regulator applications and the pruning of stems and roots. The propagation of cuttings from adult plant material is decisive for inflorescence bud formation. Increasing light intensity and day length produced a compact plant and improved floral initiation. Lowing temperatures can increase flower development. The development of the plants is not affected by root pruning. Pruning stems can not stimulate branching, however, depending on the time of application, pruning stems does promote plant growth. The crop management of special Australian acacia species as pot plants or flowering pot plants is described on charts in conclusion of the study.
134

Gerenciamento de pot?ncia reativa em sistemas de distribui??o utilizando controlador fuzzy de fator de pot?ncia

Vianna, Marcelo Pinto 20 March 2009 (has links)
Made available in DSpace on 2015-04-14T13:56:15Z (GMT). No. of bitstreams: 1 412367.pdf: 787019 bytes, checksum: 03a6312b4b2842e6cdfc928ff5fbb9ec (MD5) Previous issue date: 2009-03-20 / Esta disserta??o aborda o gerenciamento de pot?ncia reativa em sistemas de distribui??o, utilizando o conceito de controle centralizado de fator de pot?ncia como uma fun??o do DMS (Distribution Management System). A metodologia desenvolvida utiliza dois controladores fuzzy em cascata para coordenar a opera??o de bancos de capacitores e geradores s?ncronos existentes na rede de distribui??o de m?dia tens?o, com o objetivo de assegurar uma faixa adequada de fator de pot?ncia e pot?ncia reativa, utilizando como vari?veis de controle a viola??o do fator de pot?ncia, a sensibilidade dos equipamentos e a posi??o dos dispositivos de controle. A metodologia foi implementada no toolbox de l?gica fuzzy do Matlab. O controle de tens?o foi realizado de forma local pelos reguladores de tens?o e pelo transformador com mudan?a de tap da subesta??o. As viola??es de fator de pot?ncia e os n?veis de tens?o e carregamento s?o verificados por uma rotina de fluxo de pot?ncia. S?o apresentados os resultados e an?lises das simula??es de dois sistemas testes de distribui??o que demonstraram a efic?cia do modelo proposto para manter os limites operacionais dentro de faixas adequadas tanto para a concession?ria de energia como para os consumidores.
135

Vulnerabilidade extrema e pot?ncia de vida: o homo sacer contempor?neo em face da bio?tica / Extreme vulnerability and potency of life: the contemporary homo sacer in the face of bioethics

Carvalho, Ricardo Geraldo de 05 February 2018 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2018-04-13T12:06:15Z No. of bitstreams: 1 RICARDO GERALDO DE CARVALHO.pdf: 1527876 bytes, checksum: 40e81b9802f1d77c6211d92205fe80d1 (MD5) / Made available in DSpace on 2018-04-13T12:06:15Z (GMT). No. of bitstreams: 1 RICARDO GERALDO DE CARVALHO.pdf: 1527876 bytes, checksum: 40e81b9802f1d77c6211d92205fe80d1 (MD5) Previous issue date: 2018-02-05 / A presentifica??o do fen?meno religioso na realidade da finitude humana, enquanto possibilidade de transforma??o em condi??es de absoluta adversidade ou de extremo sofrimento, procurar? desvelar profundamente a vida, a temporalidade, as emo??es e a f? esperan?osa que anima os seres humanos a superar situa??es extremas que atentam contra a vida. Nesta perspectiva, surge um questionamento: de que maneira uma pessoa em situa??o de sofrimento consegue humanamente re-significar sua finitude atrav?s do fen?meno religioso que permeia a rela??o entre iman?ncia e transcend?ncia? A resposta a essa quest?o vir? a partir de reflex?o te?rica pr?pria ao campo da bio?tica, da teologia como, ainda, da filosofia, em especial, das formula??es relativas ? absoluta exclus?o humana presente na contemporaneidade, provenientes da teoria de Giorgio Agamben acerca do Homo Sacer. Configura-se uma realidade que est? al?m da possibilidade de controle das pessoas, por se tratar de uma conjectura globalizante, segundo a qual um conceito mais abrangente de vulnerabilidade faz-se necess?rio. Destarte, o fen?meno religioso iluminado pelo ?evangelho? da Vida deduz que ao sofrimento pode-se dar sentido, de modo a tornar-se acontecimento de salva??o, ao respeitar a vida e orientar o ser humano para o seu desenvolvimento integral. Em realidades de sofrimento, ? poss?vel constatar-se que na manifesta??o da pot?ncia de vida, a pessoa desenvolve a pedagogia da resili?ncia e tangencia de forma adequada a conting?ncia das circunst?ncias existenciais; com liberdade interior ativa, reconhece sua humanidade e de outrem. / A presentifica??o do fen?meno religioso na realidade da finitude humana, enquanto possibilidade de transforma??o em condi??es de absoluta adversidade ou de extremo sofrimento, procurar? desvelar profundamente a vida, a temporalidade, as emo??es e a f? esperan?osa que anima os seres humanos a superar situa??es extremas que atentam contra a vida. Nesta perspectiva, surge um questionamento: de que maneira uma pessoa em situa??o de sofrimento consegue humanamente re-significar sua finitude atrav?s do fen?meno religioso que permeia a rela??o entre iman?ncia e transcend?ncia? A resposta a essa quest?o vir? a partir de reflex?o te?rica pr?pria ao campo da bio?tica, da teologia como, ainda, da filosofia, em especial, das formula??es relativas ? absoluta exclus?o humana presente na contemporaneidade, provenientes da teoria de Giorgio Agamben acerca do Homo Sacer. Configura-se uma realidade que est? al?m da possibilidade de controle das pessoas, por se tratar de uma conjectura globalizante, segundo a qual um conceito mais abrangente de vulnerabilidade faz-se necess?rio. Destarte, o fen?meno religioso iluminado pelo ?evangelho? da Vida deduz que ao sofrimento pode-se dar sentido, de modo a tornar-se acontecimento de salva??o, ao respeitar a vida e orientar o ser humano para o seu desenvolvimento integral. Em realidades de sofrimento, ? poss?vel constatar-se que na manifesta??o da pot?ncia de vida, a pessoa desenvolve a pedagogia da resili?ncia e tangencia de forma adequada a conting?ncia das circunst?ncias existenciais; com liberdade interior ativa, reconhece sua humanidade e de outrem.
136

Samarium(II) mediated radical cascades of keto esters for the generation of molecular complexity

Plesniak, Mateusz January 2018 (has links)
A highly regio- and diastereoselective approach towards complex 6-membered lactones was developed using allyl/propargyl benzyl ethers and delta keto esters. Crucially, the classical ET reagent SmI2 gave unsatisfactory results and it was necessary to develop and screen new Sm(II) cyclopentadienyl complexes to deliver high selectivity in the transformation. The methodology was extended to a one-pot approach to complex cycloheptanols using SmI2-H2O in a second stage of the process. Samarium(II) folding cascades were developed where simple, linear starting materials are converted to complex polycyclic architectures bearing multiple stereocentres. It was found that, depending on the sidechain in the starting material, it was possible to achieve four different pathways from the common radical intermediate. Crucially, transannular 1,5-HAT from tertiary and benzylic positions was observed to give diverse products. A proposed 1,5-HAT facilitated SmI2-mediated 6-membered lactone radical cyclisations for the first time without an activating proton donor additive. Enantioselective samarium(II) mediated cyclisation cascades were achieved, where simple beta keto esters are converted to complex polycyclic architectures bearing up to five contiguous stereocentres with high diastereo- and enantiocontrol. In the process, a simple and easy to prepare chiral aminodiol was employed which could be recycled after the reaction. Unprecedented, enantioselective transannular radical cascades allowed access to unique 3- dimensional scaffolds inaccessible by other synthetic methods.
137

Gamma-Borylated allylic acetates as 3 carbons functionalized units : synthesis and applications / Acétates allyliques Gamma-borylés comme unités fonctionnalisés 3-carbone : synthèse et applications

Kukkadapu, Krishna Kishore 06 June 2013 (has links)
Les boranes vinyliques,les acides boroniques vinyliques et les boronates vinyliques sont des organoboranes où la différence d'électronégativité entre le carbone et le bore est très faible[C (2. 55)-B (2. 04)] et la liaison entre ces deux atomes est donc peu polaire. Les propriétés caractéristiques du bore permettent de réaliser une grande variété de réactions dans différentes conditions. Beaucoup de groupes de recherche ont exploré les applications synthétiques des organoboranes en synthèse organique. Par exemple les boranes vinyliques peuvent être transformés en les alcènes correspondants par protonolyse,ils peuvent être facilement oxydés avec H2O2 en présence de base(addition d'un groupe hydroxyle sur la double liaison) pour donner des produits cis-anti Markovnikov. Ils peuvent aussi subir des réactions d'addition pour donner des alcools allyliques ou des cycloadditions [4+2] pour former deux nouvelles liaisons carbone- carbone via des réactions de Diels-Alder. Les acides vinylboroniques peuvent être transformés en halogénures vinyliques via une halogénolyse,réagir via une réaction de cyclisation radicalaire utilisant la méthode catalytique de Corey en présence d'un initiateur de réaction radicalaire pour obtenir des diols 1,3- ou 1,4. Ils peuvent participer à des réactions de couplage au palladium de type Suzuki pour former de nouvelles liaisons carbone-carbone. Ils peuvent réagir avec des anhydrides pour donner différentes cétones insaturatées via des catalyses au palladium ou au rhodium . Les acides vinylboroniques ont aussi été utilisés pour la formation de nouvelles liaisons carbone-azote , carbone-oxygène , carbone-fluor via des réactions catalysées au palladium ou au cuivre. Les boronates vinyliques ont été employés pour former de nouvelles liaisons carbone-carbone via des couplages de Suzuki- Miyaura. Ils sont employés dans la réaction multicomposant de Petasis pour donner des hétérocycles azotés fonctionnalisés. Ils participent aux réactions de métathèse croisée pour donner des boronates vinyliques hautement fonctionnalisés , ils réagissent facilement avec des carbènes générés à partir de diazos pour donner des cyclopropanes et ceci à travers des catalyses au palladium et au rhodium. Les boronates vinyliques, en réaction avec des oxides de nitrile subissent des réactions de cycloaddition 1,3-dipolaire pour donner des isoxazoles . Les boronates vinyliques ont aussi été utilisés comme nucléophiles en réaction d'allylation avec catalyse au cuivre ou au palladium. Les transformations précédentes des organoboranes fournissent des précurseurs importants pour la synthèse totale de molécules bioactives complexes qui ont été utilisées dans les domaines de la médecine, de l'agrochimie, des composés pharmaceutiques et de la chimie fine. Les organoboranes peuvent être synthétisés facilement et ceci les rend particulièrement précieux comme intermédiaires clés en synthèse organique. / Vinylboranes, vinylboronic acids and vinylboronates are organoboranes where the electro negativity difference between carbon and boron bond is very low [C (2. 55)-B (2. 04)] and the bond between them is less polar. The characteristic features of borane allow performing wide range of reactions under different conditions. Several research groups explored the synthetic applications of organoboranes in organic synthesis. For example vinylboranes can be transformed to their corresponding alkenes via protonolysis,can be easily oxidized by hydrogen peroxide in presence of base(addition of hydroxy group at double bond)to result cis-,anti Markovnikov products also participate in addition reactions to give allylic alcohols,they undergo[4+2]cyclo adition reactions to form two new carbon- carbon bonds via Diels- Alder reaction. Vinylboronic acids can be transformed to vinylhalides via halogenolysis,react via boron-tethered radical cyclisation using Corey’s catalytic tributyl-stannane method in presence of radical initiator to afford 1,3- or 1,4-diols,participates in palladium catalyzed Suzuki cross coupling reactions to give characteristic carbon-carbon bond,react with anhydrides to result various unsaturated ketones via palladium and rhodium catalysis,vinylboronic acids were also used for the synthesis of new carbon-nitrogen,carbon- oxygen, carbon-fluoine bonds via palladium and copper catalysis. Vinylboronates were used to synthesize new carbon-carbon bonds via Suzuki- Miyaura cross coupling reaction under palladium catalysis, participates in Petasis multicomponent reaction to give functionalized nitrogen based heterocycles, they undergo olefin cross-metathesis to afford highly functionalized vinylboronate deivaives, readily react with carbene generated from diazo compounds to afford cyclopropane derivatives under palladium and rhodium catalysis. Vinylboronates on treatment with arylnitrile oxides undergo 1,3-dipolar cyclo addition reaction to give isoxazole derivatives, vinylboronates were also used as nucleophiles in allylation with copper and palladium catalysisThe above transformations of organoboranes provide important precursors for building complex bioactive molecules which were developed as medicine, agrochemicals, pharmaceuticals and fine chemicals. Organoboranes can be easily synthesized and this easy access for preparation made them useful key intermediates for organic synthesis. Vinylboranes can be synthesized via hydroboration of alkynes with alkylboranes,vinylboronic acids can be synthesized via hydroboration of alkynes with alkoxyboranes followed by hydrolysis where as vinylboronates were synthesized from organometallic reagents by transmetallation with trimethyl orthoborate,also prepared from hydroboration of alkynes with alkoxyboranes. Grafting a substitution in the allylic position of vinyl boronates confers to these units a high degree of versatility to their use in organic synthesis. -substitue.
138

Uso do iodeto de pot?ssio no tratamento da esporotricose em felinos dom?sticos (Felis catus domesticus, linnaeus, 1758) naturalmente infectados:an?lise cl?nica e das fun??es hep?ticas, renal e tireoidiana / Use of potassium iodide in felines (Felis catus domesticus) sporotrichosis treatment: clinical observations, and liver, kidney and thyroid evaluations

Sena, Priscila das Merc?s de 31 May 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-09-20T13:24:55Z No. of bitstreams: 1 2011 - Priscila das merces de sena.pdf: 7709054 bytes, checksum: f76077cb7fca550b09f80cf277852e82 (MD5) / Made available in DSpace on 2016-09-20T13:24:55Z (GMT). No. of bitstreams: 1 2011 - Priscila das merces de sena.pdf: 7709054 bytes, checksum: f76077cb7fca550b09f80cf277852e82 (MD5) Previous issue date: 2011-05-31 / The Spotrhrix schenckii is widely dispersed in nature, especially in temperate and tropical climates. Sporotrichosis is the most common human subcutaneousmycosis in Latin America. In domestic feline, tissues can be found with a abundance of this parasite, fact that it is not usual in other species, so becoming a significantzoonoticagent. The objective in this study was to evaluate the regressiontimeoftheclinical disease, the side effects with Potassium Iodide (KI) administration, in dosis of 10 and 20mg/kg of weight, also evaluation the total T4 hormone concentrations, as well as the possible alterations of hemogram, and renal and hepatic serum biochemistrybyusingthismedication. Were used in this experimentation 14 domestic cats (Felis catusdomesticus), 11 males and three females, with indefinite race, and a mean age of 3.7 years old and average weight of 3.9 kg, with the disease sporotrichosis, all from Rio de Janeiro city. The animal selection was done through the confirmation of the sporotrichosis disease, by collecting material and conducting to mycological culture procedure. The animals were divided into two groups randomly: group I (10 mg of KI/ kg of weight), and group II (20 mg of KI/ kg of weight). Clinical and laboratory evaluations were performed in all cats in the study. Besides the total T4, the following laboratory tests were performed: hemogram, urea, creatinine, alkaline phosphatase, alanine-aminotransferase, gamma-glutamyltransferase, aspartate-aminotransferase. All tests were repeated every 15 days, and clinical evaluation was performed daily. This study concluded after comparison between the two groups that weren?t significant alterations in time regression of disease, as well as in that laboratorial analysis, but there were differences in side effects, so, dosis of 10 mg / kg of weight, once daily was the most right treatment of feline sporotrichosis / O Spotrhrix schenckii, agente etiol?gico da esporotricose,? amplamente disperso na natureza, especialmente em ambientes de climas temperados e tropicais. A esporotricose ? a micose subcut?nea humana mais comum na Am?rica Latina, e o felino tem potencial zoon?tico significativo. O objetivo deste trabalho foi avaliar o tempo de regress?o da doen?a cl?nica e as fun??es hep?tica, renal e tiroideana, com uso do iodeto de pot?ssio (IK) nas doses de 10 ou 20 mg/kg de peso, para tratamento da micose. Foram utilizados 14 felinos dom?sticos (Felis catus domesticus), sendo 11 machos e tr?s f?meas, ra?a indefinida, com idade m?dia de 3,7 anos e peso m?dio 3,9 kg, portadores da doen?a e provenientes do Munic?pio do Rio de Janeiro. A sele??o dos animais foi realizada atrav?s da confirma??o da doen?a, por meio da coleta de material e realiza??o de cultura micol?gica. Os animais foram divididos em dois grupos, de forma aleat?ria: grupo I (dose de 10 mg de IK/kg de peso) e grupo II (dose de 20 mg de IK/kg de peso), com m?dia do tempo de tratamento de 63 dias. Avalia??o cl?nica e laboratorial foi realizada em todos os gatos do estudo. Al?m do T4 total, os seguintes exames laboratoriais foram realizados: hemograma, ur?ia, creatinina, fosfatase alcalina, alanina-aminotransferase, gama-glutamiltransferase, aspartato-aminotransferase. Todos os exames foram repetidos a cada 15 dias, do in?cio ao final dotratamento e avalia??o cl?nica foi realizada diariamente. Este estudo concluiu, comparando-se os dois grupos, que n?o houve diferen?a estatisticamente significativa no tempo de regress?o da doen?a, mas houve diferen?as nos efeitos colaterais. Os animais do grupo I que apresentaram v?mitos e diarr?ia foram em n?mero de dois e os animais do grupo II apresentaram efeits colaterais cmo v?mitos, diarr?ia, prostra??o, anorexia, desidrata??o, febre, saliva??o, pelagem seca.Sendo a dose de 10 mg/kg, uma vez ao dia, a mais adequada para o tratamento de esporotircose felina, pois n?o provocou altera??es cl?nicas, laboratoriais e hormonais significativas
139

Monitorage et Détection d'Intrusion dans les Réseaux Voix sur IP

Nassar, Mohamed 31 March 2009 (has links) (PDF)
La Voix sur IP (VoIP) est devenue un paradigme majeur pour fournir des services de télécommunications flexibles tout en réduisant les coûts opérationnels. Le déploiement à large échelle de la VoIP est soutenu par l'accès haut débit à l'Internet et par la standardisation des protocoles dédiés. Cependant, la VoIP doit également faire face à plusieurs risques comprenant des vulnérabilités héritées de la couche IP auxquelles s'ajoutent des vulnérabilités spécifiques. Notre objectif est de concevoir, implanter et valider de nouveaux modèles et architectures pour assurer une défense préventive, permettre le monitorage et la détection d'intrusion dans les réseaux VoIP.<br /><br />Notre travail combine deux domaines: celui de la sécurité des réseaux et celui de l'intelligence artificielle. Nous renforcons les mécanismes de sécurité existants en apportant des contributions sur trois axes : Une approche basée sur des mécanismes d'apprentissage pour le monitorage de trafic de signalisation VoIP, un pot de miel spécifique, et un modèle de corrélation des évenements pour la détection d'intrusion. Pour l'évaluation de nos solutions, nous avons développés des agents VoIP distribués et gérés par une entité centrale. Nous avons développé un outil d'analyse des traces réseaux de la signalisation que nous avons utilisé pour expérimenter avec des traces de monde réel. Enfin, nous avons implanté un prototype de détection d'intrusion basé sur des règles de corrélation des événements.
140

Functional Dendritic Materials using Click Chemistry : Synthesis, Characterizations and Applications

Antoni, Per January 2008 (has links)
Förfrågan efter nya och mer avancerade applikationer är en pågående process vilket leder till en konstant utveckling av nya material. För att förstå relationen mellan en applikations egenskaper och dess sammansättning krävs full förståelse och kontroll över materialets uppbyggnad. En sådan kontroll över uppbyggnaden hos material hittas i en undergrupp till dendritiska polymerer som kallas dendrimerer. I den här doktorsavhandlingen belyses nya metoder för att framställa dendrimer med hjälp av selektiva kemiska reaktioner. Sådana selektiva reaktioner kan hittas inom konceptet klickkemi och har i detta arbete kombinerats med traditionell anhydrid- och karbodiimidmedierad kemi. Denna avhandling diskuterar en accelererad tillväxtmetod, dendrimerer med inre och yttre reaktiva grupper, simultana reaktioner och applikationer baserade på dessa dendritiska material. En accelererad tillväxtmetod har utvecklats baserad på AB2- och CD2-monomerer. Dessa monomerer tillåter tillväxt av dendrimerer utan att använda sig av skyddsgruppkemi eller aktivering av ändgrupper. Detta gjordes genom att kombinera kemoselektiviteten hos klickkemi tillsammans med traditionell syraklorid kopplingar. Dendrimerer med inre alkyn- eller azidfunktionalitet syntetiserades genom att använda AB2C-monomerer. Den dendritiska tillväxten skedde med hjälp av karbodiimidmedierad kemi. Monomererna som användes bär på en C-funktionalitet, alkyn eller azid, och på så sätt byggs får interiören i de syntetiserade dendrimeren en inneburen aktiv funktionell grupp. Ortogonaliteten hos klickkemi användes för att sammanfoga monomerer till en dendritisk struktur. Traditionell anhydridkemi- och klickemireaktioner utfördes samtidigt och på så sätt kunde dendritiska strukturer erhållas med färre antal uppreningssteg. En ljusemitterande dendrimer syntetiserades genom att koppla azidfunktionella dendroner till en alkynfunktionell cyclenkärna. Europiumjoner inkorporerades i kärnan varpå dendrimerens fotofysiska egenskaper analyserades. Mätningarna visade att den bildade triazolen hade en sensibiliserande effekt på europiumjonen. Termiska studier på några av de syntetiserade dendrimerer utfördes för att se om några av dem kunde fungera som templat vid framställning av isoporösa filmer. / The need for new improved materials in cutting edge applications is constantly inspiring researchers to developing novel advanced macromolecular structures. A research area within advanced and complex macromolecular structures is dendrimers and their synthesis. Dendrimers consist of highly dense and branched structures that have promising properties suitable for biomedical and electrical applications and as templating materials. Dendrimers provide full control over the structure and property relationship since they are synthesized with unprecedented control over each reaction step. In this doctoral thesis, new methodologies for dendrimer synthesis are based on the concept of click chemistry in combination with traditional chemical reactions for dendrimer synthesis. This thesis discusses an accelerated growth approach, dendrimers with internal functionality, concurrent reactions and their applications. An accelerated growth approach for dendrimers was developed based on AB2- and CD2-monomers. These allow dendritic growth without the use of activation or deprotection of the peripheral end-groups. This was achieved by combining the chemoselective nature of click chemistry and traditional acid chloride reactions. Dendrimers with internal azide/alkyne functionality were prepared by adding AB2C monomers to a multifunctional core. Dendritic growth was obtained by employing carbodiimide mediated chemistry. The monomers carry a pendant C-functionality (alkyne or azide) that remains available in the dendritic interior resulting in dendrimers with internal and peripheral functionalities. The orthogonal nature of click chemistry was utilized for the simultaneous assembly of monomers into dendritic structures. Traditional anhydride chemistry and click chemistry were carried out concurrently to obtain dendritic structures. This procedure allows synthesis of dendritic structures using fewer purification steps. Thermal analyses on selected dendrimers were carried out to verify their use as templates for the formation of honeycomb membranes. Additionally, a light emitting dendrimer was prepared by coupling of azide functional dendrons to an alkyne functional cyclen core. A Europium ion was incorporated into the dendrimer core, and photophysical measurements on the metal containing dendrimer revealed that the formed triazole linkage possesses a sensitizing effect. / QC 20100629

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