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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.
41

Variability Of Sediment Nutrients And Benthic Macro-Invertebrates In Recreational Fishing Ponds

Stubbs, Tyler James 09 December 2011 (has links)
The overall objective of this study was to identify trends of sediment nutrients and benthic macro-invertebrates in recreational fishing ponds. The Ekman dredge and the Yabby pump, also were compared for benthic macro-invertebrate sampling effectiveness. Large ranges in the coefficient of variation for Pw (52 – 123.9), C:N (13.4 – 124), density (61.5 – 98.5), and diversity (67 – 142) indicated significant spatial variability within and among ponds. Invertebrate familial diversity was the only variable that did not show any significant temporal variation (H = 4.31, P = 0.230). Results from the gear comparison indicated no differences between the Ekman dredge and Yabby pump (3 pulls); however, showed the Ekman dredge was more effective than the Yabby pump (12 pulls) (Z = -1.796, P = 0.073) indicating potential gear saturation. Although these data supported no discernable patterns between sediment nutrients and macro-invertebrates, it provided an opportunity to detail an operational framework for future studies.
42

Nonlinear Mechanical and Actuation Characterization of Piezoceramic Fiber Composites

Williams, Robert Brett 23 April 2004 (has links)
The use of piezoelectric ceramic materials for structural actuation is a fairly well developed practice that has found use in a wide variety of applications. However, actuators with piezoceramic fibers and interdigitated electrodes have risen to the forefront of the intelligent structures community due to their increased actuation capability. However, their fiber-reinforced construction causes them to exhibit anisotropic piezomechanical properties, and the required larger driving voltages make the inherent piezoelectric nonlinearities more prevalent. In order to effectively utilize their increased performance, the more complicated behavior of these actuators must be sufficiently characterized. The current work is intended to provide a detailed nonlinear characterization of the mechanical and piezoelectric behavior of the Macro Fiber Composite actuator, which was developed at the NASA Langley Research Center. The mechanical behavior of this planar actuation device, which is both flexible and robust, is investigated by first developing a classical lamination model to predict its short-circuit linear-elastic properties, which are then verified experimentally. The sensitivity of this model to variations in constituent material properties is also studied. Phenomenological models are then used to represent the measured nonlinear short-circuit stress-strain response to various in-plane mechanical loads. Piezoelectric characterization begins with a nonlinear actuation model whose material parameters are determined experimentally for monotonically increasing electric fields. Next, the response of the actuator to a sinusoidal electric field input is measured under various constant mechanical loads and field amplitudes. From this procedure, the common linear piezoelectric strain coefficients are presented as a function of electric field amplitude and applied stress. In addition, a Preisach model is developed that uses the collected data sets to predict the hysteretic piezoelectric behavior of the MFC. Lastly, other related topics, such as manufacturing, cure kinetics modeling and linear thermoelasticity of the Macro Fiber Composite, are covered in the appendices. / Ph. D.
43

Framing a Kidnapping: Frame Convergence between Online Newspaper Coverage and Reader Discussion Posts of Three Kidnapped Romanian Journalists

Constantinescu, Ana R. 24 May 2006 (has links)
In late March 2005, three Romanian journalists were kidnapped by an obscure group of Iraqi militants near Baghdad. Several unusual details about the circumstances of the kidnapping prompted the Romanian media to investigate the speculation regarding the authenticity and motives of this high profile case. This thesis project extends framing theory to incorporate macro-level frames such as cynicism, speculation and metacommunication as dominant reporting styles in this evolving democracy. A systematic content analysis was performed on 255 news stories spanning 75 days from Evenimentul Zilei and Jurnalul National. Additionally, 2,941 of their subsequent online reader discussion posts were content analyzed using the same categories as the news stories to serve as a point of comparison between media reports and public discussion about this bizarre case. Results support evidence of generic media framing and extend the theory to demonstrate media's reliance on speculation and metacommunication as overarching reporting styles. Online deliberation between readers in this evolving democracy demonstrates difficulties in citizens' abilities to emerge from the spiral of cynicism characteristic of the post-communist Romania. While media establish the issues for public dialogue, they do not appear responsible for setting the tone. / Master of Arts
44

ERP Software implementation: An integrative framework

Al-Mudimigh, A.S., Zairi, Mohamed, Al-Mashari, M. January 2001 (has links)
No / ERP implementation is a socio-technical challenge that requires a fundamentally different outlook from technologically-driven innovation, and will depend on a balanced perspective where the organisation as a total system is considered. ERP implementation is considered to rely on behavioural processes and actions. It is a process that involves macro-implementation at the strategic level, and micro-implementation at the operational level. This therefore means that implementation in the context of ERP systems is not possible through an ON/OFF approach whereby deployment of the new systems will necessarily yield the desired and expected results. Understanding the implementation process through a balanced perspective will therefore prevent any unpleasant surprises, and will ensure and guide the change process to be embedded in a painless fashion. The balanced perspective means that socio-technical considerations must be borne in mind; the strategic, tactical and operational steps clearly defined; and the expected benefits evaluated and tracked through creating seamless and solid integration. This paper proposes an integrative framework for ERP implementation based on an extensive review of the factors and the essential elements that contribute to success in the context of ERP implementation.
45

Estudo matemático do mecanismo de regulação da esquistossomíase / Mathematical study of the mechanism of regulation of schistosomiasis

Yang, Hyun Mo 16 October 1990 (has links)
Neste trabalho foram estudados dois mecanismos de regulação de esquistossomíase: a nível de hospedeiro intermediário (Modelo de May) e a nível de hospedeiro definitivo (Modelo de Imunidade Concomitante por período de incubação). Estudou-se como ambos os modelos comportam se quando da introdução de um modelo de regulação para a população do hospedeiro intermediário. Verificou-se que o modelo de regulação por imunidade concomitante é muito mais robusto, pois além de ajustar melhor a curva de prevalência fornece uma região de estabilidade para os parâmetros epidemiológicos muito maior. / In this work two mechanisms for the regulation of the schistosomiasis were studied. In one model the regulation takes place at the intermediate host (May Model) and in the other model the regulation takes place at the definitive host (concomitant Immunity) . In both models the regulation of the intermediate host population was also included. It was found that regulation in the definitive host is much more robust than the regulation on the intermediate host allowing for a much greater range of the epidemiological parameters. Also the model of regulation on the definitive host allows for a very good fit of the prevalence curve.
46

O Juquery: sua implantação, projeto arquitetônico e diretrizes para uma nova intervenção / The Juquery: their location, architectural design and guidelines for a new intervention

Pizzolato, Pier Paolo Bertuzzi 18 April 2008 (has links)
A dissertação, seguindo a linha da evolução construtiva, analisa o desenvolvimento arquitetônico, tanto do ponto de vista estético quanto histórico, do Complexo Hospitalar do Juquery desde a administração do Dr. Franco da Rocha até os dias de hoje. A finalidade é realizar uma leitura desse espaço em vista de possíveis modificações por influências e dinâmicas sócio-urbanas dentro do contexto da Macro-metrópole paulistana, preparando-o, por meio de novos usos como, por exemplo, projetos sociais - para sua reinvenção como pólo indutor da transformação das cidades no Vale do Rio Juqueri. / This dissertation analyses the architectonical development of Juquery Hospitalar Complex, since the administration of Dr. Franco da Rocha until nowadays. The aim of this analysis is provide a provide a structure through which can be thought the possible modifications the Complex can suffer because the socio-urban dynamics, making it able to receive new uses and keeping it as POLO INDUTOR of the cities in the Rio Juquery Valley.
47

Rikbaktsa: um estudo  de parentesco e organização social / Rikbaktsa: a study of kinship and social organization

Pires, Paula Wolthers de Lorena 04 December 2009 (has links)
Esta dissertação de mestrado tem como objeto de pesquisa a população indígena Rikbaktsa, ou Canoeiros, como são conhecidos na região. Localizados no sudoeste amazônico, a noroeste do estado de Mato Grosso (Bacia do Juruena), têm um contingente populacional de aproximadamente 1200 habitantes. São filiados ao tronco lingüístico Macro-Jê e dividem-se em metades exogâmicas agnáticas organizadas em clãs patrilineares. O estudo em questão constitui-se de uma ampla pesquisa bibliográfica, revisão e sistematização dos dados Rikbaktsa, procurando colocar em diálogo os textos e materiais já produzidos sobre esta população, bem como estabelecer comparações com pesquisas realizadas sobre outras etnias Jê-Bororo. Uma ferramenta computacional (MaqPar) também contribuiu para produzir novas descrições sobre o sistema empírico de aliança Rikbaktsa. Deste modo, procurou-se debater a fundo temas relacionados à organização e morfologia social, pertencimento Rikbaktsa ao tronco lingüístico Macro-Jê e sistema de parentesco e terminologia. / This masters thesis has the Rikbaktsa indigenous society, or Canoeiros - as they are locally known - as the research object. Located on the southwest of the Amazonian range, on the north-west of the state of Mato Grosso, the Rikbaktsa people comprise a population of approximately 1200 individuals. They are filiated to the linguist trunk of Macro-Jê and are equally divided into exogamic moieties organized into fatherhood clans. This research consist of an ample bibliographic account as well as a review and systematization of available data on the Rikbaktsa people, aiming not only to expose research and materials that has been produced regarding this society but also to establish a comparative interpretation with research carried out with other Jê-Bororo ethnic groups. In addition, a computational tool (MaqPar) has contributed to the production of new descriptions about the empirical system of alliance Rikbaktsa. Thus, this research has envisaged a thorough discussion of the social organization and morphology, the Macro-Jê linguist trunk within the Rikbaktsa society and its system of kinship along with the terminology associated.
48

Recuperação da centralidade da cidade de São Paulo / Recovery of São Paulo centrality

Silva, Luis Octavio Pereira Lopes de Faria e 11 April 2008 (has links)
Discussão sobre a recuperação da condição central da colina onde se iniciou a cidade de São Paulo, através de sua atualização e potencialização pela arquitetura e desenho urbano. A atualização do Centro velho paulistano passa pela consideração de várias escalas, entre as quais a que decorre da nova dimensão da aglomeração humana de São Paulo (a macro-metrópole paulista), a escala do vale do rio Tamanduateí e a escala local. A desobrigação de o Centro velho paulistano manter todas as funções centrais metropolitanas, expandindo-as a partir da consideração da macro-metrópole, permitiu retomar o Centro Tradicional em suas funções essenciais. Defende-se a recuperação dessas funções centrais mitigadas no decorrer do século XX no Centro velho, a saber, sede do poder político municipal, estadual e da universidade, além de habitação e espaços dedicados à religião. O Centro velho é visto como o Centro da Polis paulistana, comparável ao que era o Forum para a cidade romana. É apresentado um processo de projeto que investiga a forma que o Centro atualizado pode ter e o resultado é visto como intermediário. As diretrizes que se obtém do processo prospectivo e a busca em si são vistas como contribuições para um projeto que é necessariamente coletivo. / The present thesis is a discussion on the recovery of a central condition of the hill where the city of São Paulo was founded, by updating it and involving it through architecture and urban design. Updating the old paulistano Center requires the appreciation of several scales, one of them being the one that considers the new dimension of human agglomeration in São Paulo (the paulista macro-metropolis), the scale of the Tamanduateí river valley and the local scale. Once the maintenance of all metropolitan central functions in the old Center of São Paulo is not necessary anymore, as these functions are already spread to other areas of the macro-metropolis, this enables the Traditional Center to recover its essential functions. We advocate the recovery of these central functions - the seat of state and of the city political power, the university, in addition to housing and places dedicated to religion - which have mitigated throughout the XXth century in the old Center. The old Center is considered the Center of São Paulo Polis, similar to what the Forum had been for the Roman city. This work comprises a designing process that investigates the form that the refurbished Center could have and the result of this process is still intermediate. The route obtained with the designing process and the search itself are seen as contributions for a project that is, necessarily, a collective work.
49

NMR δομικός χαρακτηρισμός του macro τομέα του ιού Mayaro και μελέτες αλληλεπίδρασης με ADPr

Μελέκης, Ευστάθιος 13 January 2015 (has links)
Οι macro τομείς αποτελούν μία οικογένεια δομών, συντηρημένη εξελικτικά σε πολλά είδη οργανισμών. Ομόλογά τους βρίσκονται σε βακτήρια, αρχαία, ασπόνδυλα, φυτά καθώς και σε θηλαστικά. Η βιολογική τους λειτουργία δεν έχει αποσαφηνιστεί πλήρως αλλά το βασικό βιοχημικό τους χαρακτηριστικό είναι η ύπαρξη μιας θετικά φορτισμένης κοιλότητας η οποία χρησιμεύει ως σημείο πρόσδεσης της διφωσφορικής αδενικής ριβόζης (ADPr). Ο macro τομέας αποτελεί επίσης μέρος των μη δομικών πρωτεϊνών ιών, οι οποίοι φέρουν ως γενετικό υλικό νοηματικό μονόκλωνο RNA. Τέτοιου είδους ιοί είναι και οι άλφα ιοί στους οποίους ανήκει και ο ιός Mayaro. Στην παρούσα εργασία, πραγματοποιείται δομική μελέτη του macro τομέα του ιού Mayaro. Με χρήση της τεχνολογίας του ανασυνδυασμένου DNA, ο πρωτεϊνικός τομέας εκφράστηκε σε μεγάλες ποσότητες και κατέστη δυνατή η μελέτη του με τη χρήση πολυπυρηνικής/πολυδιάστατης φασματοσκοπίας πυρηνικού μαγνητικού συντονισμού. Η NMR δομή του macro τομέα του ιού Mayaro επιλύθηκε σε υψηλή διακριτικότητα (tf=1.03+/-9.7*10e-2, RMSD=0.90+/-0.15 και RMSD=1.44+/-0.14 για τα άτομα της πολυπεπτιδικής αλυσίδας και τα βαρέα άτομα αντίστοιχα) και αποκάλυψε μια αβα σάντουιτς δομή στο κέντρο της οποίας σχηματίζεται μια εκτεταμένη β-πτυχωτή επιφάνεια. Στη συνέχεια πραγματοποιήθηκαν πειράματα αλληλεπίδρασης, τα οποία αποκάλυψαν ότι το ADPr αποτελεί προσδέτη στο macro τομέα του ιού Mayaro. / Macro domains are a family of structures, evolutionarily conserved in many kinds of organisms such as bacteria, archaea, invertebrates, plants and mammals. Their biological function is not fully elucidated but their key biochemical feature seems to be the binding of the Adenosine Diphosphate ribose(ADPr). Macro domain is also found in non-structural proteins of several positive strand RNA viruses like Mayaro virus, a member of the genus of Alphavirus. In the present study, a structural analysis of the macro domain of virus Mayaro is being performed. Using the technology of recombinant DNA, the macro domain was expressed in high yield, making the analysis by multinuclear/multidimensional Nuclear Magnetic Resonance possible. The NMR solution structure of the macro domain od virus Mayaro was determined in high resolution(tf=1.03+/-9.7*10e-2, RMSD=0.90+/-0.15 and RMSD=1.44+/-0.14 for backbone and heavy atoms respectively) and revealed a well folded 3-Layer(aba)Sandwich structure in the center of which, an extended beta sheet is formed. Furthermore, interaction experiments were performed which revealed that the ADPr is a ligand for the macro domain of virus Mayaro.
50

Avaliação sazonal de Carotenóides provitamina A (alfa- e beta caroteno) e vitamina E ( alfa- tocoferol) em macroalgas marinhas pertencentes ao gênero Cryptonemia / Seasonal evaluation of provitamin A carotenoids (alpha and beta-carotene) and vitamin E (alpha tocopherol) in seaweeds of the genus Cryptonemia

Nascimento, Rômulo Malta January 2009 (has links)
NASCIMENTO, Rômulo Malta. Avaliação sazonal de Carotenóides provitamina A (alfa- e beta caroteno) e vitamina E ( alfa- tocoferol) em macroalgas marinhas pertencentes ao gênero Cryptonemia. 2009. 77 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2009 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-21T14:32:00Z No. of bitstreams: 1 2009_dis_rmnascimento.pdf: 395771 bytes, checksum: 5ea80d85afb63aef84af0ad763c70f0d (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-21T14:32:18Z (GMT) No. of bitstreams: 1 2009_dis_rmnascimento.pdf: 395771 bytes, checksum: 5ea80d85afb63aef84af0ad763c70f0d (MD5) / Made available in DSpace on 2016-07-21T14:32:18Z (GMT). No. of bitstreams: 1 2009_dis_rmnascimento.pdf: 395771 bytes, checksum: 5ea80d85afb63aef84af0ad763c70f0d (MD5) Previous issue date: 2009 / The objective of this research project was to investigate the existence of seasonal variation of both provitamin A carotenoids ( and carotene) and vitamin E ( and tocopherol) in two species of red marine macroalgae, Cryptonemia luxurians and C. crenulata. The alga samples were collected monthly from January to December of 2007, during the low tides of Pacheco Beach, Caucaia, Ceará. The alga samples were dehydrated at 40°C for 15 h. The dried alga material was crushed into a fine powder and then submitted into the procedures of extraction with methanol, saponification with potassium hydroxide and partition with n-hexane. For simultaneous analyses of carotenoids and tocopherols the HPLC system consisted of a Waters Spherisorb-Hichrom S5 ODS-2 (4.6 x 250 mm) column and a mobile phase of MeOH: THF (95:5, v/v), delivered at 1.5 mL min -1 , with detection at 450 nm and 292 nm, respectively. In both species belonging to the genre Cryptonemia were detected  and carotene throughout all the sampling months. In general, both species contained larger concentrations of carotene than carotene. Despite the macroalgae analyzed belonged to the same genre, it was possible to verify a variation in the concentrations of provitamin A carotenoids throughout the year. C. luxurians was elected as a better source of vitamin A than C. crenulata. Among the isomers of vitamin E, tocopherol showed the higher concentrations. C. luxurians showed the highest levels of both tocopherols. According to these results, C. luxurians and C. crenulata oven-dried at 40°C for 15 h are possibly better sources of vitamin E than vitamin A. To verify the seasonal behavior of the concentrations of provitamin A carotenoids and vitamin E, grouping analysis was utilized. Based upon the results of this analysis it was established that tocopherol concentrations showed a more substantiated variation in the macroalgae within the seasons of the year as well as among the two species. On the other hand, the provitamin A carotenoids, exhibited more stable concentrations considering the species and the seasons. Nevertheless, only with subsequent studies it will be possible to determine the factors and its influence on the variation of provitamin A carotenoids and vitamin E contents of the analyzed species. / O objetivo do presente trabalho foi investigar a existência de variação sazonal nos conteúdos de carotenóides provitamina A ( e caroteno) e vitamina E ( e tocoferol) em duas espécies de macroalgas marinhas vermelhas, Cryptonemia luxurians e C. crenulata. As algas foram coletadas mensalmente de janeiro a dezembro de 2007, durante as marés baixas na Praia do Pacheco, Caucaia, Ceará. Em laboratório as algas foram desidratadas em estufa a 40°C por 15 horas. O material desidratado foi triturado até a obtenção de um pó fino e, em seguida, submetido aos procedimentos de extração com metanol, saponificação com hidróxido de potássio e partição em n-hexano. Para a análise simultânea de carotenóides e tocoferóis, por cromatografia líquida de alta eficiência, uma coluna Waters Spherisorb-Hichrom S5 ODS-2 (4,6 x 250 mm) e fase móvel de MeOH: THF (95:5, v/v), com fluxo de 1,5 mL min -1 foram utilizadas, com detecção em 450 nm e 292 nm, respectivamente. Em ambas as espécies pertencentes ao gênero Cryptonemia foram detectados e caroteno ao longo dos meses de coleta. De uma maneira geral, as duas espécies apresentaram maiores teores de caroteno que caroteno. Apesar de as macroalgas analisadas pertencerem ao mesmo gênero, foi possível verificar uma variação nos teores de carotenóides provitamina A ao longo do ano entre as espécies. C. luxurians pode ser eleita como melhor fonte de vitamina A que C. crenulata. Dentre os isômeros da vitamina E, tocoferol apresentou as maiores concentrações. C. luxurians exibiu os maiores teores de ambos os tocoferóis. De acordo com os resultados obtidos no presente estudo, as macroalgas marinhas C. luxurians e C. crenulata desidratadas em estufa a 40°C por 15 horas possivelmente são melhores fontes de vitamina E do que de vitamina A. Para avaliar o comportamento sazonal dos teores de  e caroteno e  e tocoferol, foi utilizada a análise de agrupamentos. A partir dessa análise constatou-se que os teores de tocoferóis apresentaram variação mais proeminente, tanto entre as estações do ano como entre as espécies, quando comparados com os carotenóides provitamina A, os quais demonstraram maior estabilidade nos teores por espécie e por estação do ano. Entretanto, somente a partir de estudos posteriores será possível determinar quais fatores e sua influência na variação dos teores de carotenóides provitamina A e vitamina E das espécies analisadas.

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