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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.
1

Možnosti určení geografického původu živočišných a rostlinných produktů pomocí stabilních izotopů kyslíku, vodíku a uhlíku. Izotopový signál keratinu krunýře želv / The possibilities of determining the geographic origin of plant and animal products by means of stable isotopes of oxygen, hydrogen and carbon. Isotope signature in keratin of tortoise´s shell

DRTINOVÁ, Martina January 2011 (has links)
This biological study is focused on the possibility of using stable isotope analyses to determine the geographic origin of plants and mainly animals especially tortoises. In the experiment nineteen tortoises were divided into two groups which were fed by isotopically different food and water for one year. The samples of keratin from their shells were collected before and after the experiment. Then the samples were analysed for the ratio of particular isotopes using isotope ratio mass spectrometry.
2

A Biogeochemistry Approach to Geographic Origin and Mortuary Arrangement at the Talgua Cave Ossuaries, Olancho, Honduras

Warner, Monica Michelle 07 May 2016 (has links)
Isotopic assays, including stable carbon, stable oxygen, and radiogenic strontium were measured for 37 individuals from the Talgua cave ossuaries to understand human movement and mortuary practice during Formative Period Honduras. Likelihood assignment models demonstrated that the individuals had diverse childhood geographic origins within the surrounding valleys. This shows that different kin or ethnic groups from diverse geographic origins were utilizing the ossuaries. Five possible ‘non-local’ individuals were identified from the radiogenic strontium and stable oxygen isotope datasets, suggesting minimal human movement into northeast Honduras from outside Lower Central America. The low number of ‘non-local’ individuals at Talgua Caves also suggests that trade items were acquired by down-the-line exchange processes rather than through a long-distance trade connection. This type of trade network and bioarchaeological evidence of limited ‘non-local’ individuals at Talgua Caves suggests the surrounding region was culturally distinct from Mesoamerica during the Formative Period.
3

Levantamento florístico e colonização micorrízica em dois remanescentes de cerrado típico e em plantas ruderais no município de Três Lagoas-MS

Neto, Maria José [UNESP] 30 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-30Bitstream added on 2014-06-13T19:05:40Z : No. of bitstreams: 1 neto_mj_dr_ilha.pdf: 993776 bytes, checksum: 2b507122c2d5ec15ebaf77777529b841 (MD5) / Universidade Estadual Paulista (UNESP) / Este trabalho foi realizado em dois remanescentes de Cerrado sentido restrito conhecidos por Reserva do Exército e Parque Municipal Capivaras; e numa área urbanizada denominada Vila Piloto, localizados no Município de Três Lagoas - MS. Nesta última foi realizado o levantamento de plantas ruderais. Nas três áreas fez-se o levantamento da diversidade florística e coletou-se amostras de plantas em fase jovem para verificação de colonização micorrízica arbuscular. Amostras compostas de solo também foram coletadas para contagem de esporos e análise das características químicas do solo. A área de Reserva do Exército mostrou um total de 397 espécies, distribuídas em 241 gêneros e 70 famílias. Das 44 espécies submetidas à análise de colonização micorrízica, 17 tiveram muito alta, 18 alta, oito baixa e uma ausente. O Parque Capivaras exibiu 449 espécies, distribuídas em 277 gêneros e 96 famílias. Das 44 espécies submetidas à análise de colonização micorrízica, 22 tiveram muito alta, 15 alta, uma baixa e seis ausente. Para a Vila Piloto foram identificadas 344 espécies distribuídas em 201 gêneros e 61 famílias, três espécimes determinados apenas em nível de gênero, das 344 espécies 281 são nativas do Brasil e 76 são típicas de cerrado ou cerradão. Das 50 espécies de plantas ruderais escolhidas para verificação da colonização micorrízica, 27 exibiram colonização muito alta, três alta, duas média, onze baixa e sete espécies não apresentaram colonização micorrízica. Os solos das áreas estudadas se apresentam com teores médios para alumínio e matéria orgânica. A média de esporos por 100g de solos foi de 53 para o Exército e 48 para o Parque Capivaras, permitindo sugerir que as áreas estão em equilíbrio. Para a Vila Piloto os resultados da amostragem do solo para os dois pontos coletados revelaram uma fertilidade que pode ser... / This research was accomplished in two restricted sense cerrado remnants, one of them known as the Military Reserve and the other the Municipal Park of Capivaras. The other area was in an urbanized region named Vila Piloto, located in Três Lagoas - MS County, where a floristic survey of ruderal plants was made. In all three areas, a survey of floristic biodiversity was done and samples of young plants were collected to verify arbuscular mychorhizal colonization. Soil samples were also taken for counting spores and for analyzing its chemical characteristics. The Military Reserve displayed a total of 397 species, distributed in 241 genera and 70 families. Of the 44 species submitted to mychorrhizal colonization analyses, 17 were very high, 18 high, eight low and one absent. The Capivaras Park displayed 449 species, distributed in 277 genera and 96 families. Of the 44 species submitted to the mychorhizal colonization analysis, 22 had very high, 15 high, one had low and six had no colonization. For Vila Piloto, 344 species were identified and distributed in 201 genera and 61 families, and three specimens determined only in the genus level. Of the 344 species, 281 are natives to Brazil and 76 are typical of Cerrado or Cerradão. Fifty species from ruderal plants were chosen for verification of the mychorhizal colonization, of which 27 species displayed very high colonization, three high, two medium, eleven low and seven species did not present mychorhizal colonization. The soil of the studied area has medium content for aluminum and organic material. The average number of spores per 100g of soil was 53 for the Reserve and 48 for the Park, suggesting that the areas were in equilibrium. The results from Vila Piloto soil samples collected from two points revealed a fertility that can be considered higher than the typical Cerrado and an average number of FMA spores of 152 per 100g of dry soil ... (Complete abstract click electronic access below)
4

[pt] ANÁLISE MULTIELEMENTAR E DE RAZÕES ISOTÓPICAS COMO FERRAMENTAS DE DENOMINAÇÃO DE ORIGEM GEOGRÁFICA DE VINHOS BRASILEIROS / [en] MULTIELEMENTAL ANALYSIS AND OF ISOTOPIC RATIOS LIKE AS TOOL OF BRAZILIAN WINES GEOGRAPHIC ORIGIN

18 November 2021 (has links)
[pt] A busca de níveis superiores de qualidade, tempo e competitividade é uma preocupação constante das agências econômicas e no setor agro - alimentar não poderia ser diferente. Um crescente número de pesquisas tem sido publicado detalhando o uso de técnicas analíticas para a determinação do conteúdo mineral, razões isotópicas ou de ambos como descritores geográficos de diferentes produtos agrícolas desde alimentos frescos até produtos processados. A pesquisa de vinhos no Brasil ainda é muito restrita aos pólos produtores de vinhos do país. E, a maior parte dos trabalhos tem como o objetivo a análise de parâmetros clássicos de controle de qualidade, sendo recente em nosso país a pesquisa envolvendo o desenvolvimento e/ou aplicações de metodologias que possam caracterizar o vinho e sua região produtora. Técnicas espectrométricas, como a ICP-OES, ICP-MS, são as mais utilizadas para este propósito e, foram utilizadas neste trabalho. Pela primeira vez o estudo das razões isotópicas de boro e chumbo foi aplicado aos vinhos brasileiros. A análise e classificação dos componentes principais (PCCA) e a análise de agrupamentos (CA), foram utilizadas no processamento dos dados. As regiões Sul e Nordeste puderam ser definidas utilizando tanto os dados da caracterização inorgânica quanto os isotópicos, mas não o suficiente para se definir as regiões produtoras de vinhos do Rio Grande do Sul, em especial o Vale dos Vinhedos. Ficou claro neste trabalho que o emprego da estatística multivariada aos dados obtidos através das determinações inorgânicas e isotópicas é uma poderosa ferramenta analítica. / [en] The search for higher levels of quality, time and competitiveness is a constant concern of economic agencies and agro - food could not be different. A growing body of research has been published detailing the use of analytical techniques for determining the mineral content, isotopic ratios or both as geographical descriptors of different agricultural products from fresh food to processed products. A search of wines in Brazil is still very restricted to the poles wine producers in the country. And, most of the work has as objective the analysis of classical parameters of quality control, and recent research in our country involving the development and / or application of methodologies that characterize the wine and its producing region. Spectrometric techniques such as ICP-OES, ICP-MS, are the most used for this purpose and were used in this study. For the first time the study of the isotopic ratios of lead and boron was applied to the Brazilian wines. The analysis and classification of the major components (PCCA) and cluster analysis (CA) were used for data processing. The South and Northeast could be identified using data from both inorganic as the isotopic characterization, but not enough to define the wine producing regions of Rio Grande do Sul, particularly the Valley of the Vineyards. It became clear in this study that the use of multivariate statistical data obtained through the inorganic and isotopic determinations is a powerful analytical tool.
5

Les supports de peintures en bois dans les anciens Pays-Bas méridionaux de 1450 à 1650 : analyses dendrochronologiques et archéologiques / Wood painting supports in the southern part of the ancient Low Countries from 1450 to 1650 : dendrochronological and archaeological analyses

Fraiture, Pascale 05 July 2007 (has links)
Résumé L'examen archéologique et dendrochronologique des panneaux peints permet dappréhender les caractéristiques techniques relatives à la fabrication des supports de peinture. Puisque le corpus duvres couvre deux siècles de peinture dans les anciens Pays-Bas méridionaux, les analyses mettent en évidence les permanences ou les évolutions techniques de la mise en uvre du bois, et peuvent dès lors contribuer à une histoire matérielle de lart. Parallèlement, il est indispensable dintégrer la confection des supports dans un cadre plus large de production, en relation avec le contexte politique, économique et religieux de la région et de la période couvertes par notre étude. Le corpus duvres sur lequel repose cette thèse compte 143 peints datés entre 1450 et 1650. Quil sagisse de retables ou de panneaux de chevalet, tous ont été confectionnés et peints sur le territoire des Pays-Bas méridionaux, principalement dans des centres tels que Bruges, Bruxelles ou Louvain, aux XVe et XVIe siècles, ainsi quAnvers, aux XVIe et XVIIe siècles. La majeure partie des tableaux est issue du marché libre qui se développe dès la fin du XVe siècle dans les différents centres urbains ; quelques peintures de commande sy ajoutent. À lépoque qui nous occupe, le marché des panneaux peints est en pleine expansion. Au XVIe siècle, la demande en peintures de chevalet explose : posséder des tableaux fait partie des préoccupations de la bourgeoisie, même modeste. Au long de la période envisagée, le statut du panneau peint est ainsi passé de produit dexception (uvres de commande) à celui de produit usuel (panneaux de chevalet disponibles en grandes quantités sur le marché libre). Au XVIIe siècle, Anvers devient le fournisseur en peintures pour toutes les grandes villes dEurope. Au-delà dune meilleure compréhension ponctuelle de la chaîne opératoire de la fabrication des supports de peinture, des investigations dordre plus général ont été menées, pour replacer la réalisation du panneau destiné à être peint dans un contexte de production en pleine mutation. Laccroissement de la production de peintures sur bois dans les Pays-Bas méridionaux principalement au nord du pays soulève la question de lapprovisionnement en chêne, essence exclusive pour la confection des supports, dautant que la couverture forestière régionale est clairsemée et compte peu dindividus aux qualités requises pour la production de planches de panneaux. Ce constat conduit à sinterroger sur les sources qui ont permis de répondre à la demande en planches par les villes flamandes et brabançonnes. Dans ce contexte, il convenait également de prendre en considération les conséquences éventuelles sur lapprovisionnement en bois allochtone des bouleversements politiques et religieux qui secouèrent lEurope entière, à partir du troisième tiers du XVIe siècle et jusquaux traités de Westphalie au milieu du XVIIe siècle. Comme la période couverte par notre recherche (de la fin du moyen âge au début de lépoque moderne) est marquée par dimportantes évolutions techniques, il était intéressant de mesurer limpact que ces progrès ont pu avoir dans le domaine de la production des panneaux peints, et en particulier sur le débitage des planches nécessaires à leur confection. Dès lors, il était utile de sinterroger sur les conséquences de la scission survenue entre les Pays-Bas du Nord, grands spécialistes du sciage des planches, et ceux du Sud, qui dépendaient en grande partie de leurs voisins hollandais pour leur approvisionnement. Le développement considérable de la demande en peintures de chevalet a nécessairement conduit à une augmentation tout aussi importante de la demande en supports prêts à être peints. Des documents darchives attestent dailleurs que les artisans du bois ne parvenaient plus à honorer les innombrables demandes. Il était donc justifié de sinterroger sur les moyens quils ont mis en uvre pour améliorer leur productivité et leur rentabilité. À côté de ces constatations dordre contextuel, et plus concrètement, le matériel détude a nécessité le développement dune méthodologie propre à lexamen dendrochronologique des panneaux peints. Les résultats enregistrés et discutés tout au long de ce travail ont permis déclairer les apports et les limites de lapplication de cette discipline à des objets tels que les supports de peinture. Ils ont également mené à la constitution dun nouveau référentiel dendrochronologique adapté à la datation de peintures sur bois des anciens Pays-Bas. Abstract Archaeological and dendrochronological analyses of panel paintings yield results with respect to the technical characteristics related to the fabrication of the painting supports. Since the corpus of works studied covered two centuries of painting in the southern part of the ancient Low Countries, such analyses demonstrate persistence or technical development in woodworking, and thus contribute to the material history of art. Similarly, it is indispensable to integrate the production of supports within the broader framework of production, in relation to the political, economic and religious context of the region during the period covered by this study. The corpus of works on which this thesis is based comprises 143 panel paintings dated between 1450 and 1650. Whether altarpieces or easel paintings, all were created and painted in the southern Low Countries, principally in centres such as Bruges, Brussels and Leuven, during the 15th and 16th centuries, as well as in Antwerp, during the 16th and 17th centuries. The majority of the paintings are the result of the open market which developed at the end of the 15th century in different urban centres; several paintings made on order have also been studied. During the period of interest, the market for panel painting was in full expansion. In the 16th century, the demand for easel painting exploded: to own paintings was one of the interests of the bourgeoisie, even if modest. During this period, the status of the panel painting thus changed from being a rare commodity (works by order) to widespread (easel paintings available in large quantities on the open market). In the 17th century, Antwerp became the source of paintings for all of the large cities in Europe. Beyond a better, but episodic, understanding of the production sequence to prepare painting supports, investigation at a broader scale has also been carried out in order to place the production of panels destined to be painted within the context of production in full transformation. The rise in the production of paintings on wood in the southern Low Countries mainly in the northern part of the country raises the questions of procurement of oak, the exclusive material for supports, since the regional forest cover was sparse and had few trees with the qualities required for the production of panel planks. This observation led to investigation of the sources of wood responding to the demand for planks by Flemish and Brabant towns. In this context, it was also appropriate to consider the possible consequences of political and religious upheavals on non-local wood procurement from the last third of the 16th century to the Westphalia treaties in the middle of the 17th century. As the period examined in this research (end of the Middle Ages to the beginning of the Modern Era) is marked by significant technological developments, the impact of this progress in the area of panel painting production, and in particular on the cutting techniques of planks needed for their supports, was addressed. As a result, it was useful to examine the consequence of the scission between the northern Low Countries, specialists in sawing planks, and the southern part, which depended in large part on their Dutch neighbours for procurement. The considerable development in the demand for easel paintings necessarily led to an equally important increase in the demand for supports ready to be painted. Archival documents also show that wood artisans were no longer able to meet the innumerable requests. It was thus relevant to investigate the means they employed to improve their productivity and profitability. Next to these contextual observations, and more concretely, the material studied required the development of a methodology specific to the dendrochronological analysis of panel paintings. The results recorded and discussed throughout this thesis allow clarification of the contribution and limits of the application of this discipline to objects such as painting supports. They have also led to the construction of a new dendrochronological frame of reference adapted to the dating of paintings on wood in the ancient Low Countries.
6

Évaluation du Potentiel des Rapports Isotopiques Stables du Strontium et du Plomb pour l'Origine Géographique et l'Authenticité des Produits Alimentaires / Assessing the Potential of Stable Isotope Ratios of Strontium and Lead for Geographical Origin and Authenticity of Food Products

Polekh-Epova, Ekaterina 04 May 2018 (has links)
L'authenticité et la traçabilité des aliments gagnent un intérêt croissant au cours de la dernière décennie puisque la connaissance de la provenance des aliments est considérée comme une garantie supplémentaire de leur qualité. Les consommateurs ont également des inquiétudes et des préoccupations par l'origine de la nourriture qu'ils consomment car divers produits sont sujets à l'adultération ou à la fausse dénomination. L'intérêt accru à l’égard de la protection des consommateurs et de la lutte antifraude ont entraîné un accroissement de la recherche scientifique appliquée et le développement d'outils efficaces pour contrôler l'authenticité des produits alimentaires. Entre techniques analytiques appliquées à l'authenticité et à la traçabilité des aliments, les méthodes les plus prometteuses sont basées sur les empreintes d'éléments lourds mesurées par la spectroscopie atomique. La spectrométrie de masse à multicollection à couplage à plasma induit (MC-ICP-MS) est reconnue comme la méthode optimale pour effectuer des mesures de haute précision de nombreux éléments du tableau périodique en contrôlant simultanément les rapports entre leurs isotopes stables. Cette étude présente une nouvelle stratégie analytique basée sur des isotopes stables non-traditionnels combinés avec des éléments traces déterminés par ICP-MS. Les avantages de combiner les informations de deux systèmes isotopiques, l'un traçant le sol (Sr), et l'autre traçant la pollution environnementale ambiante (Pb), ont permis d'obtenir de nouvelles informations exceptionnelles sur la traçabilité et l'authenticité des matrices alimentaires sélectionnées : vins de Bordeaux, jambons secs et thé. En utilisant des techniques analytiques complémentaires telles que les empreintes des élémentaires traditionnelles, la spécification régionale, ainsi que le traçage du processus de préparation des aliments sont possibles. Traitée par la chimiométrie, cette approche analytique constitue un nouvel outil efficace et prometteur pour détecter des fraudes alimentaires, y compris l’imitation de produits de grande valeur, l’étiquetage erroné et la substitution par des produits moins cher. / Food authenticity and traceability have received an increasing interest during the last decade since the knowledge of food provenance is regarded as an additional warranty of its quality. The world's globalization brought to the consumers is more and more concerned with the origin of the food they eat because various products are subjected to adulteration or false denomination. The augmentative interest in anti-fraud and consumer protection has led to the extension of scientific research and development of effective tools of food authenticity control. Among the analytical technics applied to food authenticity and traceability, one of the most rapidly developing and promising method is based on fingerprinting of heavy elements detected by atomic spectroscopy. The multicollection inductively coupled plasma mass spectrometry (MC-ICP-MS) is recognized as a method of choice for the high precision measurement of numerous elements of the periodic table as well as ratios of their stable isotopes. This study present a new analytical strategy based on combined non-traditional stable isotopes and trace elements determination by ICP-MS. The benefits of combining information from two isotopic systems, one tracing the soil (Sr), and the other tracing environmental ambient pollution (Pb), allowed to obtain an exceptional new information about traceability and authenticity of selected food matrixes: prestigious Bordeaux wines, dry-cured hams and tea. Using complementary analytical techniques such as traditional elemental fingerprinting, the regional specification, as well as tracing of the food preparation process are possible. When combined with chemometrics, these analytical advances constitute an efficient and promising tool to detect food frauds, including adulteration of high value products with cheaper substitutes, forgery and falsification.

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