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Estudo espectroscópico de anticorpos empregando-se superfícies SERS-ativas visando o desenvolvimento de imunossensores / Spectroscopic study of antibodies employing SERS-active surfaces for the development of immunosensorsRaquel Mariano de Almeida 15 April 2016 (has links)
Este estudo empregou anticorpos que podem ser peças chaves no eventual desenvolvimento de imunossensores, devido as suas características de seletividade e consequente determinação de espécies de interesse em análises clínicas, ambiental, saúde publica, entre outros. Para isto, foram feitos estudos de espectros Raman e SERS de anticorpos inteiros e/ou fragmentados (IgG humana, anti-IgG humana (H+L) e anti-IgG humana (Fab2)). Com isto, foram conhecidos os principais modos vibracionais destas biomoléculas que são úteis para a proposta de se construir imunossensores. Ambas as técnicas fornecem informações a respeito da estrutura secundária de proteínas. Quando há a imobilização dessas biomoléculas sobre superfícies SERS-ativas, é possível determinar a sua orientação. Considerando-se que na técnica SERS existe a possibilidade de se detectar uma molécula, por meio de hot spots, é importante que as imunoglobulinas estejam sem impurezas como, por exemplo, a albumina e transferrina no caso de anticorpos provenientes do soro humano. Assim, foram feitos experimentos de purificação dos anticorpos por meio de colunas de afinidade contendo proteína A, G ou uma mistura de A e G imobilizadas e, também, separação baseada no ponto isoelétrico. Testou-se a capacidade de ligação (quimissorção) de IgG humana ou de seus fragmentos F(ab)\' sobre superfícies de ouro por meio da técnica QCM-D. Para o estudo de superfícies SERS-ativas foram sintetizadas nanopartículas de ouro (NP-Au), com a aquisição de espectros de extinção no UV-Vis e obtenção de imagens MEV para caracterizá-las. Também, foram feitas variações no preparo de nanocubos de ouro (NC-Au) para obtenção de nanobastões de ouro (NB-Au), tendo-se em vista que estruturas com pontas favorecem a intensificação do sinal Raman em superfícies SERS-ativas. Por fim, considerando-se a existência de diversas ligações S-S, principalmente na região denominada dobradiça, no espectro SERS de IgGh diluída e do fragmento F(ab)\' constatou-se o surgimento de uma banda característica de C-S em 679 cm-1. Por isso, foi feita uma proposta da possível orientação desses anticorpos não fragmentados para que assumissem uma orientação sobre as superfícies SERS-ativas com características semelhantes às dos fragmentos F(ab)\'. / This study used antibodies that can be key elements in the possible evelopment of immunosensors, due to its selectivity and the consequent determination of species of interest in clinical analysis, environmental, public health, among others. For this, Raman and SERS spectra studies were made of whole and/or fragmented antibodies (human IgG, anti-human IgG (H + L) and anti-human IgG (Fab2)). With this, it were known the main vibrational modes of these biomolecules, useful for the proposal to assemble immunosensors. Both techniques provide information on the secondary structure of proteins. When these biomolecules are immobilized on SERS-active surfaces, it is possible to determine their orientation. Considering that, in the SERS technique, it is possible to detect a molecule through hot spots, it is important that the immunoglobulins are free of impurities, such as albumin and transferrin in the case of antibodies from human serum. Thus, purification experiments of antibodies were made via affinity columns containing protein A, G or a mixture of A and G immobilized and also separation based on isoelectric point. It was tested the binding capacity (chemisorption) of human IgG or its F(ab)\' on gold surfaces by means of QCM-D technique. For the study of SERS-active surfaces of gold nanoparticles were synthesized (Au-NP), with the acquisition of extinction spectra in the UV-Vis and obtaining SEM images to characterize them. Also, changes were made in the preparation of nanocubes gold (Au-NC) to obtain gold nanorods (Au-NR), having in view that ends with structures favor the enhancement of Raman signal on SERS-active surfaces. Finally, considering the existence of various S-S links, particularly in the region called hinge, in the SERS spectrum of diluted hIgG and F(ab)\', it was found the display of a characteristic band C-S 679 cm-1. Therefore, a proposal was made about the possible direction of these non-fragmented antibodies to assume an orientation on the SERS-active surfaces with similar characteristics to the F(ab)\'
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Conception, synthèse et développement de nouveaux composés antituberculeux selon une approche par fragments / Design, synthesis and development of novel antituberculosis agents by fragment-based approachTran, Ngoc Chau 26 June 2015 (has links)
En 1993, l’Organisation Mondiale de la Santé déclarait que la tuberculose était « une urgence de santé publique mondiale ». Plus de 20 ans après, cette maladie infectieuse causée par Mycobacterium tuberculosis, reste toujours un problème à l’échelle de la planète. Malgré des progrès très importants enregistrés dans la lutte contre la tuberculose dans le monde, l’OMS estime que 9 millions de personnes ont contracté cette maladie en 2013 et que 1,5 million sont morts durant cette même année. De plus, l'émergence de la tuberculose multirésistante nécessite le développement de nouveaux outils et de nouvelles stratégies thérapeutiques. Récemment, deux nouveaux composés, bedaquiline et delamanid ont reçu une autorisation temporaire d’utilisation dans le but de renforcer l’arsenal thérapeutique. Néanmoins, il existe toujours la possibilité que la bactérie puisse rapidement développer des résistances liées au mécanisme d’action de ces nouveaux médicaments. C’est pour toutes ces raisons que l’arsenal thérapeutique doit être renforcé. Ce travail de thèse repose sur la découverte et l'optimisation de nouveaux composés antituberculeux selon des approches dont le point de départ commun est le criblage de petites molécules appelées fragments.La première partie de ce manuscrit présente la continuité d’un travail démarré au cours de la thèse de Baptiste Villemagne et qui a pour but de potentialiser l’activité de l'éthionamide, un médicament antituberculeux utilisé pour le traitement de seconde intention. Le répresseur transcriptionnel EthR a été validé comme élément clé dans la bioactivation de l’éthionamide. Les inhibiteurs de cette cible, développés selon une approche par fragments ont permis de potentialiser l'activité de l'éthionamide in vitro. Cependant, la faible stabilité microsomale de ces composés a limité leur utilisation in vivo. L’étude de la métabolisation du composé tête de série et la modification structurale de ce dernier a permis le développement des nouveaux inhibiteurs d’EthR présentant des propriétés pharmacocinétiques et physico-chimiques désormais acceptables pour la réalisation de tests in vivo.La deuxième partie de cette thèse s’est concentrée sur la synthèse d’inhibiteurs de MabA, une β-cétoacyl-ACP réductase mycobactérienne participant à la synthèse des acides gras à longue chaîne, précurseurs des acides mycoliques qui sont les constituants majeurs de la paroi mycobactérienne. Cette enzyme a été montrée comme étant indispensable à la survie de la bactérie mais aucun inhibiteur à ce jour n’a été identifié. Le criblage d’une chimiothèque de fragments sur MabA a été réalisé via deux tests différents (un test d’affinité pour la cible (TSA) et un test enzymatique). Les hits ainsi identifiés ont été resynthétisés et testés dans un test fonctionnel. Les étapes d’optimisation de l’activité des hits reconfirmés sont ainsi décrites. Ces résultats ont permis de développer des composés présentant des activités de l’ordre du micromolaire. Dans la troisième partie, un travail de conception et de synthèse de nouveaux fragments, visant à compléter la chimiothèque actuelle a été effectué. Les fragments originaux contenant un motif isoxazoline ont été synthétisés à partir d’alcènes et d’aldoximes utilisés en tant que synthons de départ, selon une réaction de cycloaddition 1,3-dipolaire. L’analyse conformationnelle de ces fragments a permis de montrer que ces structures venaient enrichir l’espace de la diversité, notamment par l’introduction d'un motif permettant le déploiement des substituants dans les trois dimensions de l’espace. La solubilité expérimentale de ces fragments a été également mesurée et nous avons pu montrer que ces molécules étaient adaptées au criblage. / In 1993, the World Health Organization (WHO) declared Tuberculosis (TB) as a global public health emergency. Over 20 years later, this infectious disease caused by Mycobacterium tuberculosis, remains a major public health problem. Despite the significant progress in the fight against TB worldwide, WHO estimates that 9 million people contracted the disease in 2013 and 1.5 million died in that year. In addition, the emergence of multidrug-resistant tuberculosis (MDR-TB) requires the development of new tools and new therapeutic strategies. Recently, two new compounds, bedaquiline and delamanid were approved in MDR-TB treatment in order to strengthen the actual MDR-TB chemotherapy. Nevertheless, there is always the possibility that the tubercle bacillus can quickly develop resistance related to the mechanism of action of these new drugs. Therefore, the actual therapeutic arsenal must be strengthened. This thesis is based on the discovery and optimization of new anti-TB compounds starting from the screening of small molecules called fragments.The first part of this thesis is the continuation of the research project which was started during the thesis of Baptiste Villemagne. This work aims to develop compounds that can boost the activity of ethionamide, a second-line drug used to treat MDR-TB. The transcriptional repressor EthR has been validated as a key element in the bioactivation of ethionamide. EthR inhibitors were identified using a fragment-based approach and were optimized to potentiate the activity of ethionamide in vitro. However, the low microsomal stability of the lead compound has limited its use in vivo. The metabolism study of the lead compound and key structural modifications allowed a development of new potent EthR inhibitors having acceptable pharmacokinetic and physico-chemical properties for in vivo testing.The second part of this thesis focused on the synthesis of MabA inhibitors. MabA is a mycobacterial β-ketoacyl-ACP reductase involved in the synthesis of long-chain fatty acids, precursors of mycolic acids, which are major constituents of the mycobacterial cell wall. This enzyme has been shown to be essential for the survival of the bacteria but until now no inhibitor has been identified. Screening of a library of fragment molecules on MabA was performed via two different assays (affinity assay using TSA and an enzymatic assay). The identified hits were re-synthesized and tested in a functionnal assay. The optimization steps to improve the activity of the hits are also described. Compounds with activity in the micromolar range were discovered.In the third part, a design and synthesis of new fragments is described. The aim of this project is to build a collection of original fragments showing a 3D-structure scaffold amenable for rapid derivatization. The fragments that contain an original isoxazoline motif were synthesized from alkenes and aldoxime as starting building-blocks by using 1,3-dipolar cycloaddition. The conformational analysis of these structures has shown that they were, as expected, able to deploy substituents in the 3D space. The experimental solubility of these fragments was also measured and the results demonstrated that these molecules are suitable for the screening against new biological targets to help kick-start hit discovery program.
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Geoprocessamento e an?lise ambiental para determina??o de corredores de h?bitat na Serra da Conc?rdia, Vale do Para?ba RJ / Geoprocessing and environmental analysis to corridors delimitation in Serra da Conc?rdia, Vale do Para?ba - RJCaldas, Aiga Jucy Fuchshuber da Silva 28 June 2006 (has links)
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Previous issue date: 2006-06-28 / The principal goal of this paper is the formulation of a methodology that allowed the
delimitation of the more suitable areas to corridors on Serra da Conc?rdia, Para?ba River
Valley, Rio de Janeiro State, using geoprocessing tools. The fragmentation status and the
permanent preservation areas status were processed and analysed. Were also processed the
soils, the use of the land, the legal destination of the areas, slope, aspect and surfaces
curvature, generating thematics maps on a 1:50.000 scale. The steps were produced with the
softwares Arcview, Armap, Arcinfo, GPS Track Maker e PCOrd. There were determined
weights between zero and one to the attributes of the themes according to their suitability of
forest recovering. These themes were then processed with map algebra to generate the areas
according to their potential for the establishment of corridors. To evaluate the dynamics of the
forest recovering in the period between 1985 and 2004 were used images of different sensors.
There were found six soils classes, the most representative of them Cambissolos H?plicos tb
distrt?ficos, that in association with Latossolo Vermelho-Amarelo distr?fico occupies 79,8%
of the area. The secondary forests occupy the south faces of the hills much more than the
north faces. The stages medium and advanced of the secondary forests represent about 49% of
the area and are distributed in 72 fragments, two of them bigger than 1.000 ha. The permanent
preservation areas represent 53% of Serra da Conc?rdia, being 62.3% of them recovered with
secondary forest vegetation. There was a real increment of about 200 ha in the forested areas
between 1985 and 2004. The distance among the fragments is small, only one of them is farer
than 350 meters, which facilitates dispersion. However the fragments outlines are very
irregulars and they have larges border areas, making them more vulnerables. The
methodology used to generate the more suitable areas for corridors was efficient. / O objetivo principal deste trabalho foi elaborar metodologia que permitisse determinar as
?reas mais adequadas para instala??o de corredores de h?bitat na regi?o da Serra da
Conc?rdia, Vale do Para?ba, Estado do Rio de Janeiro, utilizando ferramentas de
geoprocessamento. Foram levantados e analisados a situa??o atual da fragmenta??o florestal e
das ?reas de preserva??o permanente da regi?o, al?m dos solos e do uso da terra. A partir do
modelo digital de eleva??o foram derivados os temas de declividade, faces de orienta??o e a
curvatura das superf?cies, todos na escala 1:50.000. Foram utilizando os programas Arcview,
Armap, Arcinfo, GPS Track Maker e PCOrd. Todos os temas selecionados foram convertidos
para o formato matricial e para seus atributos foram estabelecidos pesos com valores entre 0 e
1, de acordo com a sua adequabilidade para recupera??o natural da vegeta??o florestal com a
finalidade de formar corredores. Estes temas foram posteriormente processados atrav?s de
?lgebra de mapa para determinar as ?reas com maior potencial para estabelecimento de
corredores de vegeta??o. Para avalia??o da din?mica da cobertura florestal no per?odo de
1985 a 2004 foram utilizadas imagens de diferentes sensores. Foram encontradas seis classes
de solos, das quais a mais representativa ? a dos Cambissolos H?plicos tb distrt?ficos, que
associado ao Latossolo Vermelho-Amarelo distr?fico ocupa 79,8% da ?rea. A vegeta??o
florestal est? mais presente na face sul do que na face norte das vertentes. A vegeta??o
secund?ria nos est?gios m?dio e avan?ado de regenera??o representa cerca de 49% da ?rea e
est? distribu?da em 72 fragmentos, dois dos quais maiores que 1.000 ha. As ?reas de
preserva??o permanente ocupam 53% da Serra, estando 62,3% cobertos por vegeta??o
secund?ria nos est?gios m?dio e avan?ado de regenera??o. As regi?es ciliares s?o as ?reas de
preserva??o permanente menos preservadas. No per?odo de 1985 a 2004 houve um aumento
real de aproximadamente 200 ha de ?rea de florestas. A dist?ncia entre os fragmentos ?
pequena, apenas um est? a mais de 350m, o que facilita a dispers?o de prop?gulos e de
indiv?duos. No entanto, os contornos dos fragmentos s?o bastante irregulares, com grande
?rea de borda, o que os deixa mais vulner?veis. A metodologia utilizada mostrou-se eficiente
para escolha das ?reas mais adequadas para estabelecimento de corredores de h?bitat.
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Prédiction des résidus impliqués dans le noyau du repliement et classification structurale de fragments protéiques en interaction.Prudhomme, Nicolas 09 November 2009 (has links) (PDF)
Nous avons développé un algorithme de prédiction des résidus impliqués dans le noyau du repliement par des approches couplées. La prédiction des Most Interacting Residues (MIR) est associée aux méthodes d'analyse structurale par fragments, les Tightened End Fragments (TEF) et d'alignement multiple. Cet algorithme a été développé sur une banque de protéines à faible identité en séquence appartenant à une famille bien documentée, les immunoglobulines. Les résultats obtenus sont comparés à ceux produits par d'autres techniques similaires, mais aussi à ceux provenant d'études expérimentales. Comme résultat nous avons pu voir qu'il existe une bonne corrélation entre les résidus prédits par notre méthode et les données expérimentales. Dans une deuxième partie, nous avons généré une banque de multimères biologiques dans le but de développer un outil de prédiction de la structure quaternaire. La banque est validée par le programme DiMoVo utilisant la représentation des protéines par tesselation de Voronoï. Afin d'analyser les modes d'interaction entre domaines, les différents complexes ont été découpés en fragments par la méthode des Tightened End Fragments. Nous avons développé un algorithme permettant d'inclure chaque fragment dans un cylindre, afin de pouvoir caractériser le fragment par une hauteur et un rayon. Ces fragments ont ensuite été classés sur ces critères structuraux et les interactions de différentes classes de fragments au sein des interfaces protéines-protéines ont été comptabilisées. On observe que les classes ne sont pas utilisées de façon homogène dans les interactions protéines-protéines.
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Développement d'un dispositif expérimental basé sur la<br />digitalisation des signaux et dédié à la caractérisation des<br />fragments de fission et des neutrons prompte émisVarapai, Nathallia 07 December 2006 (has links) (PDF)
Ce travail de thèse décrit la mise en place d'un dispositif expérimental basé sur la digitalisation des signaux et dédié à l'étude des neutrons prompts de fission émis en coincidence avec les fragments de fission lors de la fission spontanée du 252Cf. Ce dispositif comprend une chambre à ionisation utilisée pour la détection des fragments de fission ainsi qu'un scintillateur liquide de type NE213 pour la détection des neutrons prompts. Nous montrons comment l'analyse délicate des signaux digitalisés nous a permis de déterminer à la fois les distributions en masse et en énergie cinétique des fragments de fission ainsi que le spectre en énergie et la multiplicité des neutrons de fission
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Propriétés et Modes de désexcitation des noyaux chauds observés dans la réaction 36Ar sur 58Ni avec le détecteur INDRA.Nalpas, Laurent 14 November 1996 (has links) (PDF)
Les collisions d'ions lourds aux énergies de Fermi conduisent à la formation de noyaux chauds. <br />Selon l'énergie d'excitation mise en jeu, plusieurs modes de décroissance sont observés, en particulier une émission de fragments complexes (Z>2), dont l'origine est encore mal comprise. <br />Le GANIL permet d'explorer sur une large gamme en énergie, entre 32 et 95 MeV/u, la fonction d'excitation du système Ar+Ni depuis l'« évaporation » jusqu'à la «vaporisation » complète des noyaux chauds en particules légères (neutrons, isotopes de H, He). <br />L'analyse des mécanismes de réaction a montré, pour des petits paramètres d'impact, la domination des collisions binaires très inélastiques. <br />Ces dernières ont motivé une analyse en deux sources, des événements bien mesurés par le détecteur INDRA, à l'aide d'une méthode de reconstruction fondée sur l'«arbre minimum». <br />Des énergies d'excitation voisines de 20 MeV/A sont atteintes, à 95 MeV/u, dans les collisions centrales. <br />Pour les collisions violentes, le partage de l'énergie n'est plus équilibrée entre les deux partenaires, le quasiprojectile ayant une énergie d'excitation par nucléon plus élevée que la quasi-cible. <br />Entre 2 et 8 MeV/A d'énergie d'excitation totale du système, correspond une phase de production importante de fragments de masses intermédiaires qui sature autour de 10 MeV/A. <br />Le déclin du régime de «multifragmentation», au-delà de 15 MeV/A, coïncide avec la probabilité croissante d'observer la «vaporisation» des deux noyaux chauds, dont le seuil se situe aux environs de 8 MeV/A. <br />Par ailleurs, l'augmentation régulière de la température extraite des rapports isotopiques He-Li en fonction de l'énergie d'excitation du quasi-projectile suggère une évolution progressive des modes de décroissance des noyaux chauds, en accord avec les prédictions de modèles statistiques. <br />Aucun signe d'une transition de phase du premier ordre de type liquide-gaz n'est observé pour ces noyaux légers.
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Los fragmentos de Lucilio en la "edición" inédita de Antonio Agustín: estudio y comentarioMiralles Maldonado, José Carlos 28 October 1993 (has links)
En los manuscritos 7901 y 7902 de la Biblioteca Nacional de Madrid se nos han conservado unos "Fragmenta ueterum scriptorum Latinorum", recopilados por el humanista español Antonio Agustín (1517-1586. Tras los fragmentos de algunos poetas latinos se nos han transmitido algunos comentarios métricos y textuales, elaborados por el humanista italiano Gabriele Faerno (1510-1561). El objetivo de nuestro trabajo es analizar las aportaciones de estos humanistas a la Crítica Textual de los fragmentos de Lucilio. / In the manuscripts 7901 and 702 from the Biblioteca Nacional of Madrid we find a collection of "Fragmenta ueterum scriptorum Latinorum" gathered by the Spanish humanist Antonio Agustín (1517-1586). After the fragments of some poets there are some metrical and textual notes to the fragments, written by the Italian humanist Gabriele Faerno (1510-1561). The aim of our work is to analyze the contributions of these scholars to the textual criticism of Lucilius' fragments.
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Towards of a theory of reconstructing ancient librariesMamoli, Myrsini 22 May 2014 (has links)
The library was one of the most important institutions in the Hellenistic and Roman city, as evidenced in the writings of ancient authors, and the building remains of libraries found throughout the Greco-Roman world, from Asia Minor to France and from Africa to Northern Greece. Yet, the library remains one of the least easily identifiable building forms and one of the most difficult to reconstruct, because unlike architectural types such as the temple, stoa, or theater, the library exhibits significant variety in design, scale and monumentality and the use of different component elements.
In reconstructing libraries, scholars often rely on a prescribed set of assumptions about components and their arrangement that limit our ability to identify libraries and understand their diversity of arrangement. This dissertation proposes shape grammars as an effective computational methodology to identify, understand, and reconstruct ancient libraries of diverse and variant scale, design and monumentality. The work presents a comprehensive documentation of known and identified libraries, reviews the design principles of the architectural form of ancient libraries, and on the basis of this historical analysis proposes a shape grammar for the formal specification of ancient Greek and Roman libraries.
The library grammar encodes the design principles of ancient libraries in ninety-one rules
that are grouped in two major parts: the first generates the main hall of the library and its interior design, and the second generates the complete layout of the library including additional porticoes, peristyles, exedras, gardens and propylon. The application of the rules generates libraries of diverse scales and monumentality: libraries known in the corpus and as well as hypothetical libraries.
The dissertation presents grammatical derivations for the seventeen known and identified libraries. These derivations, depending on the degree of preservation of the building remains of libraries, function as an evaluative tool for the validity of the grammar or for the reconstructions proposed by traditional research. In many cases, they point to different possibilities in the identification of the building remains related to libraries among remains of different phases or remains belonging to neighboring buildings, and suggest variant scenarios of reconstruction that might not stand out using traditional techniques of reconstruction. The metadata of the rules in the grammar and the derivations are used in a frequency analysis that provides a probabilistic model as an effective and systematic guide in identifying, evaluating and predicting the architectural form of libraries: the main hall and the threshold are identified as mandatory architectural components, the niches and focal point as most likely, and the podium with a colonnade as less likely to occur in a library. Less frequently, the library is a whole complex with exedras, a monumental entry and additional rooms that function as auditoria, banquet halls or offices.
Moreover, the work presents the derivations of possible libraries and evaluates the rules applied to generate them based on the frequency analysis. In the end, the work concludes
whether these buildings are libraries, non-libraries or exceptional libraries.
Lastly, this dissertation assesses the opportunities and challenges that emerge in using shape grammars to identify and reconstruct libraries and also the value and impact of using formal computational methods in the systematic exploration of variations in reconstruction of the archaeological record.
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Gene therapy with interferon alpha and the angiogenic inhibitor, vasostatin, in neuroendocrine tumors of the digestive system /Liu, Minghui, January 2007 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2007. / Härtill 4 uppsatser.
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Importância da matriz na estrutura de comunidade de besouros carpófilos em paisagem fragmentada / Importance of matrix in the community structure carpophiles beetles in fragmented landscapeAraujo, Lucimar Soares de 22 February 2010 (has links)
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Previous issue date: 2010-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Understand how the distribution and the movement behavior of animals interact with landscape structure to generate patterns of distribution is the main goal of landscape ecology. We assume that the main source of biodiversity of the carpophiles beetles (Coleoptera) in the Zona da Mata (Minas Gerais - Brazil) are the remnants of original vegetation - forest fragments, and that different types of matrix show differences in permeability of this fauna, whether by micro-climatic characteristics that allow the persistence of organisms from the wood, either to differences in the availability of resources, enabling the establishment of these insects in the array. Therefore, we sampled nine forest fragments that were surrounded with the following matrices: three with coffee plantation, three with Eucalyptus plantation and three with pasture. In these environments the beetles were collected and measured the variables to test the hypothesis that resource availability, environmental conditions and habitat heterogeneity are determinants of the distribution of beetles. Carpophile beetles answered to the distance inside the forest differently depending on the type of matrix, but none of the environmental variables explained this response. The abundance of beetles decreases with distance from forest in pasture matrix, and did not change in matrix of the coffee and Eucalyptus plantation. The richness of beetles decreased in pasture matrix, did not change in Eucaliptus plantation matrix, but increased with distance from of the forest in coffee plantation. These patterns are importants for understanding the dynamics of populations that disperse between fragments and thus reduce the chance of extinction and maintain the diversity within the forest fragments. In addition, our results it is impotant to discuss the determinants of the diversity of these insects in agro-forest landscape, evaluating components that operate in the regulation of species in a community marked by human action. / Entender como a distribuição e o comportamento de movimento dos animais interagem com a estrutura da paisagem para gerar padrões de distribuição é o principal objetivo da ecologia de paisagens. Neste trabalho, partimos do pressuposto de que a principal fonte de biodiversidade de besouros carpófilos (Coleoptera) na região da Zona da Mata (no estado de Minas Gerais) são os remanescentes da cobertura vegetal original - os fragmentos florestais, e que diferentes tipos de matriz apresentam diferenças de permeabilidade a esta fauna, seja por características micro-climáticas que permitam a permanência de organismos vindos da floresta, seja por diferenças na disponibilidade de recursos, que permitam o estabelecimento destes insetos na matriz. Para isso foram amostrados nove fragmentos florestais que faziam limite com as seguintes matrizes: três com cafezal, três com eucaliptal e três com pastagem. Nesses ambientes foram coletados os besouros, e medidas as variáveis para testar a hipótese de que disponibilidade de recurso, condições ambientais e heterogeneidade do hábitat são determinantes da distribuição de besouros. Besouros carpófilos responderam à distância do interior da floresta de forma diferente dependendo do tipo de matriz, porém nenhuma das variáveis ambientais explicou esta resposta. A abundância de besouros diminui com a distância da floresta em matriz de pastagem e não se alterou em matriz de cafezal e eucalipto. A riqueza de besouros diminuiu em matriz de pastagem, não se alterou em matriz de eucaliptal, porém aumentou com a distância da floresta em matriz de cafezal. Esses padrões são fundamentais para o conhecimento da dinâmica das populações que se dispersam entre os fragmentos e, dessa forma, reduzem a chance de sua extinção e mantém a diversidade dentro dos fragmentos florestais. Além disso, permite discorrer sobre os determinantes da diversidade desses insetos na paisagem agro-florestal, avaliando os componentes que atuam na regulação das espécies numa comunidade marcada pela ação humana.
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