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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.
211

Evaluating The Validity Of The PEAK-E Assessment and the Efficacy of the PEAK-E Curriculum in a Single-case Evaluation

Gutknecht, Kylie Frances 01 May 2016 (has links)
The present study evaluated the utility of the methods outlined in the Promoting the Emergence of Advanced Knowledge Relational Training System Equivalence Module (PEAK-E) through a single-case evaluation. Validity, reliability, and effectiveness were the variables explored to assess the degree to which the assessment was able to identify appropriate skills for targeted intervention, and the degree to which the programs were efficacious in teaching the targeted skills. Baseline results suggested that the programs identified through the PEAK-E assessment were not within the participants’ repertoires prior to the intervention. Following the implementation of 9 programs across three participants with autism, mastery was achieved for all of the directly trained relations, and all targeted derived relations emerged for 8 of the 9 programs
212

Um estudo da emergência de gêneros no Facebook / A study on the genres emergence on Facebook

Lima Neto, Vicente de January 2014 (has links)
LIMA NETO, Vicente de. Um estudo da emergência de gêneros no facebook. 2014. 313f. – Tese (Doutorado) – Universidade Federal do Ceará, Departamento de Letras Vernáculas, Programa de Pós-graduação em Linguística, Fortaleza (CE), 2014. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2015-06-03T15:23:41Z No. of bitstreams: 1 2014_tese_vlneto.pdf: 6741088 bytes, checksum: c8c2887b869763a6df67d580216e326c (MD5) / Approved for entry into archive by Márcia Araújo(marcia_m_bezerra@yahoo.com.br) on 2015-06-05T11:00:10Z (GMT) No. of bitstreams: 1 2014_tese_vlneto.pdf: 6741088 bytes, checksum: c8c2887b869763a6df67d580216e326c (MD5) / Made available in DSpace on 2015-06-05T11:00:10Z (GMT). No. of bitstreams: 1 2014_tese_vlneto.pdf: 6741088 bytes, checksum: c8c2887b869763a6df67d580216e326c (MD5) Previous issue date: 2014 / This research aims at investigating criteria which mark the emergence of discourse genres phenomenon present in social network, especially on Facebook. Such genres take place in digital support, as well as in their generic blends that constitute language practices on the web. This study is led by a Bakhtinian language conception (BAKHTIN, 1929) and a social rhetoric genre perspective (MILLER, 1984; 1994; BAZERMAN, 2005). Besides, in search for a concept of emergence, this investigation was based on the Complexity Theory which supports the Complex Adaptive System (LARSEN-FREEMAN, 2008). In order to achieve its aim, this research was divided into two methodological parts: firstly, we selected 331 updated posts out of Facebook news feed from April 2011 to December 2012, which standard criteria were laid on the fact that these latter presented 100 shares and 100 likes. Secondly, we took a sample out of this corpus, divided it into eight questionnaires developed in to the Google Docs tool, each one carrying, at least, three posts. After that, we posted these same posts on Facebook for two months, so that the network users throughout the five regions of Brazil could post their opinion over the genres therein presented. At last, this study found 575 users’ answers to be helpful to map eight discourse genres characteristics under emergence on Facebook. Based on these latter ones, we propose six criteria to define emergence as a stage through which a genre pass toward standardization. Such a stage denotes, on one hand, a type of recurrence of recognized, accepted and socially practiced standards. On the other hand, this same stage denotes amorphous elements, under its modeling and recognition process by the community: the remix process, finishing, links, rapid saturation, lack of consent over the name and genres proposes. / Esta pesquisa tem como objetivo investigar os critérios que balizam o fenômeno da emergência de gêneros discursivos que se manifestam nas redes sociais, mais especificamente no Facebook, tomando como base o suporte digital e as mesclas genéricas que constituem as práticas de linguagem na web. Nossa investigação é conduzida por uma concepção de linguagem de base epistemológica bakhtiniana (BAKHTIN, 1929) e por uma perspectiva sociorretórica de gêneros (MILLER, 1984; 1994; BAZERMAN, 2005). Além disso, em busca de um conceito de emergência, apoiamo-nos na perspectiva da Teoria da Complexidade, que dá guarida aos Sistemas Adaptativos Complexos (LARSEN-FREEMAN, 2008). Para alcançar o objetivo, tivemos dois momentos metodológicos: no primeiro, selecionamos 331 postagens no mural de notícias do Facebook atualizadas no período de abril de 2011 a dezembro de 2012, cujos critérios básicos eram o de que tivessem pelo menos 100 compartilhamentos e 100 curtições. No segundo, extraímos uma amostra desse corpus, dividimo-la em oito questionários desenvolvidos na ferramenta Google Docs, cada um com pelo menos três postagens, e os divulgamos no Facebook pelo período de dois meses, para que os usuários da rede espalhados pelas cinco regiões do Brasil nos dessem suas impressões sobre os gêneros que ali ganham morada. Ao fim, tivemos 575 sujeitos, cujas respostas nos ajudaram a mapear as características de oito gêneros discursivos em emergência no Facebook e, com base nelas, propor seis critérios para definir a emergência como um estágio por que passa um gênero em direção à estandardização, estágio este que denota, de um lado, certa recorrência de padrões já reconhecidos, aceitos e praticados socialmente e, de outro, elementos amorfos, em processo de moldagem e de tipificação pela comunidade: o processo de remix, o acabamento, os links, a rápida saturação, a falta de consenso sobre o nome e a falta de consenso sobre os propósitos dos gêneros.
213

Contrôle de processus dynamiques par systèmes multi-agents adaptatifs : application au contrôle de bioprocédés / Self-adaptive Multi-Agent Systems to Control Dynamic Processes : an application on bioprocesses control

Videau, Sylvain 06 July 2011 (has links)
Cette thèse a pour cadre le contrôle auto-adaptatif de procédés biologiques et son objectif est de permettre l'application de ce contrôle à une grande variété de problèmes distincts en évitant la phase usuelle de leur modélisation. Les bioprocédés sont des systèmes complexes, hautement dynamiques et parvenir à les contrôler en vue d'obtenir une production définie se révèle une tâche difficile. De plus, les incertitudes liées aux mesures et le manque de connaissances des réactions biologiques précises se déroulant à l'intérieur même du bioprocédé, font que les méthodes usuelles mises en œuvre pour contrôler un bioprocédé particulier doivent être largement re-calibrées dès qu'il s'agit d'adapter ce contrôle à un bioprocédé différent. L'apport de cette thèse est de proposer une approche informatique de cette problématique, centrée sur l'utilisation de Systèmes Multi-Agents Adaptatifs (AMAS). Les propriétés auto-organisatrices de tels systèmes, ainsi que leur conception centrée sur les comportements locaux, permettent d'appréhender la complexité des procédés biologiques et de fournir un système apte à leur contrôle sans nécessiter d'informations détaillées sur ceux-ci, tout en étant capable de s'adapter à leurs dynamiques. Deux systèmes multi-agents adaptatifs distincts, répondant chacun à un ensemble de contraintes différentes, ont permis d'étudier la faisabilité et l'apport de cette approche au domaine du contrôle de procédés. L'aboutissement est un modèle AMAS générique qui est associé à chaque variable contrôlable du procédé afin d'apprendre et de déterminer les actions de contrôle pour atteindre les objectifs définis par l'utilisateur. Les agents observent en temps réel l'évolution des variables du procédé pour en extraire les informations nécessaires à son contrôle. Le système de contrôle établit alors une contextualisation des contrôles à appliquer qui devient indépendante de la connaissance du bioprocédé. Ce contrôle auto-adaptatif a été évalué sur un ensemble de problèmes de contrôle de systèmes dynamiques, notamment celui d'un bioprocédé simulé, et les résultats obtenus sont analysés dans ce mémoire / This work aims at creating a self-adaptive approach to control bioprocesses while still being generic enough to be applied on a wide range of problems without relying on their modeling. Bioprocesses are complex and highly dynamic systems, and controlling them to reach a user-defined objective is a difficult task. Furthermore, the limited amount of available measures and the lack of a precise biological knowledge of what is happening inside the bioprocess lead usual control approaches to be recalibrated before being applied on a different bioprocess. The benefit of this work is a computer-based approach relying on the Adaptive Multi-Agent Systems (AMAS) theory. The objectives of adaptability and genericity are reached thanks to the self-organization of such systems and their design focusing on the local behavior of the agents, dealing with the complexity of such a problem without needing an extensive amount of information on the system to control.Two distinct multi-agent systems, defined by a specific set of constraints, were created to study the feasibility and benefits of such an approach. The outcome is a generic AMAS model, associated with each controllable variable, which learns the actions to apply in order to fulfill user-defined objectives. Agents observe in real-time the evolution of the variables and extract the information needed to control the target system. The AMAS is then able to contextualize the control without modeling the behavior of the system to control itself.This self-adaptive control was evaluated on a set of problems involving the control of dynamic systems, such as bioprocesses, and the associated results are analyzed
214

A emergência do sistema olivícola no Estado do Rio Grande do Sul

Rodrigues, Rodrigo Maldonado January 2016 (has links)
As preocupações, desejos e necessidades dos consumidores à jusante tendem a guiar, cada vez mais, as iniciativas dos produtores à montante e esta é uma realidade também na agricultura, com a seleção de alimentos mais saudáveis, saborosos e com valor agregado por parte dos compradores, gerando um ambiente propício para produtos com estas características. O azeite extra virgem de oliva, cujas características se enquadram nos novos hábitos alimentares, vem assumindo uma posição de destaque entre os consumidores do mundo todo e não é diferente no Brasil. A despeito da pouca tradição na produção olivícola, o Brasil e em especial o Rio Grande do Sul, ao longo da última década tem iniciado uma produção concreta deste alimento, o qual vem chegando lentamente às gôndolas dos supermercados locais e nacionais gozando de uma reputação excelente. Diante, portanto, da possível emergência deste sistema de produção agrícola, da demanda potencial deste produto e da possibilidade de satisfazê-la por meio da produção local em contraposição às importações, entendeu-se que um estudo deste fenômeno recente e por conseguinte pouco analisado pode lançar as bases teóricas para a sua compreensão. Assim, teorias ligadas à governança foram utilizadas para a identificação da organização e coordenação do sistema. Para a análise dos elementos básicos do sistema, o referencial teórico utilizado foi o de sistemas complexos e para a compreensão da relação dos elementos básicos na formação de um sistema complexo, aplicou-se o ferramental da economia institucional evolucionária. Em função deste referencial teórico e da problemática a ser trabalhada, optou-se por um método reconhecidamente institucional com uma abordagem qualitativa, ou seja, um estudo de caso em modo exploratório, realizando entrevistas com participantes considerados chave no sistema e submetendo posteriormente os dados colhidos no campo aos dados secundários e ao referencial teórico. Os resultados encontrados apontam para um gradual florescimento da organização do sistema, com a coordenação não mercadológica do setor, entende-se governança, a cargo dos governos estadual e federal, mas não foram encontrados, até o momento, indícios de uma governança por parte da base, isto é, dos produtores. No que tange ao relacionamento dos elementos para a emergência do sistema, verificou-se que esta se dá por meio das trocas de informações constantes e transações que ocorrem entre os agentes e a economia local, influenciando uns aos outros em uma dinâmica base-topo e no sentido inverso, topo-base, quando o sistema reage às influências e inicia a estimular as estruturas de governança e infra-estrutura institucional. Nesta perspectiva, entende-se que os elementos do sistema que está efetivamente emergindo foram caracterizados, bem como sua relação com a economia local e que é imprescindível, para os participantes, que este sistema complexo seja entendido e tratado como tal, com intervenções adequadas, de modo que possa, desta forma, propiciar ganhos a todos os envolvidos. / Consumers concerns, desires and necessities in downstream tend to increasingly guide initiatives of producers in the upstream and this is a reality also in agriculture, with the selection of healthier, tastier, and with higher market value food, which generates a welcoming environment for products with such characteristics. Extra virgin olive oil, whose characteristics fit in the new dietary habits, has been assuming a highlighted position among consumers from the whole world, which is not different in Brazil. Despite having little tradition in olive cultivation, Brazil, especially the state of Rio Grande do Sul, has started since the last decade a solid production of this product, which has slowly reached national and international supermarkets’ shelves while receiving an excellent reputation. Therefore, with the possible emergence of this agricultural production system, and by the high demand of the product as well as the possibility of fulfilling this demand through local production instead of imports, we assume that a study about this recent, and consequently little studied, phenomenon can provide theoretical basis for its comprehension. Hence, governance theories were used to identify the system’s organization and coordination. In order to analyze basic elements of the system, the theoretical background used was that of complex systems; for the comprehension of the basic elements’ relation in the formation of a complex system, the apparatus of institutional-evolutionary economics was applied. Having in mind this theoretical background and the problem studied, we opted for a method acknowledgedly institutional with a qualitative approach i.e. an exploratory case study conducting interviews with participants considered as fundamental in the system, submitting afterwards the data collected in field to the secondary data and the theoretical background. The results obtained point to a gradual blooming of the system’s organization, with coordination not subjected to the market action of the sector, by which is understood governance, of Federal and State responsibility. However, until the moment evidences were not found of a governance of the base i.e. the producers. In reference to the relationship of the elements for the system’s emergence, it was verified that this occurs by means of constant information exchange and transactions that occur between the agents and the local economy. The agents and the local economy influence each other reciprocally in a bottom-up dynamics and in the reverse, topdown, when the system reacts to influences and begins to stimulate governance structures and institutional infrastructure. In this perspective, it is understood that the system’s elements that are effectively emerging were characterized, as well as their relation with local economy. It is crucial for the participants that this complex system can be understood and treated as so, with adequate interventions in a way that it can propitiate gains to all parts involved.
215

Testes para avaliar o potencial fisiológico de sementes de beterraba

Silva, Josué Bispo da [UNESP] 27 March 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-27Bitstream added on 2014-06-13T18:45:35Z : No. of bitstreams: 1 silva_jb_dr_jabo.pdf: 199072 bytes, checksum: 14fd74baadfa1ee3eebbb79f63e6a4fa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) / O uso de testes de vigor é imprescindível na avaliação do potencial fisiológico das sementes produzidas e comercializadas por uma empresa. O trabalho, dividido em duas etapas, teve por objetivo estudar diferentes testes para avaliar o potencial fisiológico de sementes de beterraba. Com base nos resultados, concluiu-se que os testes de EA, EASS-20, EASS-40 e DC podem ser utilizados para avaliar o potencial fisiológico de sementes de beterraba; o uso de soluções salinas apresenta vantagem sobre o procedimento tradicional; o ajuste do TA das sementes no teste de deterioração controlada deve ser feito pelo método do substrato úmido. / The use of vigor tests is essential to evaluate the physiological potential of seed lots produced and selled by a company. The work, separated in two stages, aimed to study different vigor tests to evaluate the physiological potential of beetroot seeds. With base in the results, it was concluded that EA, EASS-20, EASS-40 and DC tests can be used to evaluate the physiological potential of beet seeds; the use of solutions presents advantage on the traditional procedure; the adjustment of seed MC in the controlled deterioration test would be done by the method of humid substratum.
216

Beyond Reductionism and Emergence: A Study of the Epistemic Practices in Gene Expression Research

January 2016 (has links)
abstract: A central task for historians and philosophers of science is to characterize and analyze the epistemic practices in a given science. The epistemic practice of a science includes its explanatory goals as well as the methods used to achieve these goals. This dissertation addresses the epistemic practices in gene expression research spanning the mid-twentieth century to the twenty-first century. The critical evaluation of the standard historical narratives of the molecular life sciences clarifies certain philosophical problems with respect to reduction, emergence, and representation, and offers new ways with which to think about the development of scientific research and the nature of scientific change. The first chapter revisits some of the key experiments that contributed to the development of the repression model of genetic regulation in the lac operon and concludes that the early research on gene expression and genetic regulation depict an iterative and integrative process, which was neither reductionist nor holist. In doing so, it challenges a common application of a conceptual framework in the history of biology and offers an alternative framework. The second chapter argues that the concept of emergence in the history and philosophy of biology is too ambiguous to account for the current research in post-genomic molecular biology and it is often erroneously used to argue against some reductionist theses. The third chapter investigates the use of network representations of gene expression in developmental evolution research and takes up some of the conceptual and methodological problems it has generated. The concluding comments present potential avenues for future research arising from each substantial chapter. In sum, this dissertation argues that the epistemic practices of gene expression research are an iterative and integrative process, which produces theoretical representations of the complex interactions in gene expression as networks. Moreover, conceptualizing these interactions as networks constrains empirical research strategies by the limited number of ways in which gene expression can be controlled through general rules of network interactions. Making these strategies explicit helps to clarify how they can explain the dynamic and adaptive features of genomes. / Dissertation/Thesis / Doctoral Dissertation Philosophy 2016
217

Biomechanical Constraints on Molar Emergence in Primates

January 2017 (has links)
abstract: Across primates, molar-emergence age is strongly correlated to life-history variables, such as age-at-first-reproduction and longevity. This relationship allows for the reconstruction of life-history parameters in fossil primates. The mechanism responsible for modulating molar-emergence age is unknown, however. This dissertation uses a biomechanical model that accurately predicts the position of molars in adults to determine whether molar emergence is constrained by chewing biomechanics throughout ontogeny. A key aspect of chewing system configuration in adults is the position of molars: the distal-most molar is constrained to avoid tensile forces at the temporomandibular joint (TMJ). Using three-dimensional data from growth samples of 1258 skulls, representing 21 primate species, this research tested the hypothesis that the location and timing of molar emergence is constrained to avoid high and potentially dangerous tensile forces at the TMJ throughout growth. Results indicate that molars emerge in a predictable position to safeguard the TMJ during chewing. Factors related to the size of the buffer zone, a safety feature that creates greater stability at the TMJ during biting, account for a large portion of both ontogenetic and interspecific variation in the position of emergence. Furthermore, the rate at which space is made available in the jaws and the duration of jaw growth both determine the timing of molar emergence. Overall, this dissertation provides a mechanical and developmental model for explaining temporal and spatial variation in molar emergence and a framework for understanding how variation in the timing of molar emergence has evolved among primates. The findings suggest that life history is related to ages at molar emergence through its influence on the rate and duration of jaw growth. This dissertation provides support for the functionally integrated nature of craniofacial growth and has implications for the study of primate life history evolution and masticatory morphology in the fossil record. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2017
218

Assessing Performance, Role Sharing, and Control Mechanisms in Human-Human Physical Interaction for Object Manipulation

January 2017 (has links)
abstract: Object manipulation is a common sensorimotor task that humans perform to interact with the physical world. The first aim of this dissertation was to characterize and identify the role of feedback and feedforward mechanisms for force control in object manipulation by introducing a new feature based on force trajectories to quantify the interaction between feedback- and feedforward control. This feature was applied on two grasp contexts: grasping the object at either (1) predetermined or (2) self-selected grasp locations (“constrained” and “unconstrained”, respectively), where unconstrained grasping is thought to involve feedback-driven force corrections to a greater extent than constrained grasping. This proposition was confirmed by force feature analysis. The second aim of this dissertation was to quantify whether force control mechanisms differ between dominant and non-dominant hands. The force feature analysis demonstrated that manipulation by the dominant hand relies on feedforward control more than the non-dominant hand. The third aim was to quantify coordination mechanisms underlying physical interaction by dyads in object manipulation. The results revealed that only individuals with worse solo performance benefit from interpersonal coordination through physical couplings, whereas the better individuals do not. This work showed that naturally emerging leader-follower roles, whereby the leader in dyadic manipulation exhibits significant greater force changes than the follower. Furthermore, brain activity measured through electroencephalography (EEG) could discriminate leader and follower roles as indicated power modulation in the alpha frequency band over centro-parietal areas. Lastly, this dissertation suggested that the relation between force and motion (arm impedance) could be an important means for communicating intended movement direction between biological agents. / Dissertation/Thesis / Doctoral Dissertation Biomedical Engineering 2017
219

The Physics of Open Ended Evolution

January 2017 (has links)
abstract: What makes living systems different than non-living ones? Unfortunately this question is impossible to answer, at least currently. Instead, we must face computationally tangible questions based on our current understanding of physics, computation, information, and biology. Yet we have few insights into how living systems might quantifiably differ from their non-living counterparts, as in a mathematical foundation to explain away our observations of biological evolution, emergence, innovation, and organization. The development of a theory of living systems, if at all possible, demands a mathematical understanding of how data generated by complex biological systems changes over time. In addition, this theory ought to be broad enough as to not be constrained to an Earth-based biochemistry. In this dissertation, the philosophy of studying living systems from the perspective of traditional physics is first explored as a motivating discussion for subsequent research. Traditionally, we have often thought of the physical world from a bottom-up approach: things happening on a smaller scale aggregate into things happening on a larger scale. In addition, the laws of physics are generally considered static over time. Research suggests that biological evolution may follow dynamic laws that (at least in part) change as a function of the state of the system. Of the three featured research projects, cellular automata (CA) are used as a model to study certain aspects of living systems in two of them. These aspects include self-reference, open-ended evolution, local physical universality, subjectivity, and information processing. Open-ended evolution and local physical universality are attributed to the vast amount of innovation observed throughout biological evolution. Biological systems may distinguish themselves in terms of information processing and storage, not outside the theory of computation. The final research project concretely explores real-world phenomenon by means of mapping dominance hierarchies in the evolution of video game strategies. Though the main question of how life differs from non-life remains unanswered, the mechanisms behind open-ended evolution and physical universality are revealed. / Dissertation/Thesis / Doctoral Dissertation Physics 2017
220

Disponibilidade de minerais, germinação e vigor de sementes de milho

Magalhães, Stefânia Caixeta [UNESP] 23 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-23Bitstream added on 2014-06-13T18:57:40Z : No. of bitstreams: 1 magalhaes_sc_me_jabo.pdf: 624079 bytes, checksum: 37a746a1dac768fd2d8f6dcc974b9b8d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A maioria dos métodos utilizados para estimar o vigor de amostras de sementes são qualitativos, portanto sujeito a erros do avaliador e de interpretação dos resultados. Metodologias quantitativas podem constituir alternativas mais confiáveis. Este trabalho teve como objetivo verificar se os níveis de alguns minerais armazenados nas sementes e disponibilizados durante etapas iniciais do processo de germinação constituem indicadores sensíveis e confiáveis do nível de vigor de sementes de milho. Vinte lotes de milho foram avaliados pelos testes de germinação, de condutividade elétrica, frio e de emergência da plântula. Após 12 h, 24 h, 36 h e 48 h do início da germinação, foram avaliados também as concentrações de fósforo inorgânico (Pi), fósforo, cálcio, potássio e magnésio por meio das técnicas de análise de injeção em fluxo (FIA) e de espectrometria de emissão ótica acoplada a plasma de argônio induzido (ICP-OES). Para estas análises, os minerais foram extraídos de amostras moídas com água a 95ºC, agitadas por 30 minutos e centrifugadas. Concluiu-se que as concentrações de Pi, P, Ca, Mg e K, extraídos pelo método da água aquecida, em sementes de milho híbrido após determinados períodos de germinação, permitiram agrupar amostras de lotes de sementes de forma idêntica à permitida pelos resultados obtidos com vários testes utilizados para avaliar o nível de vigor de amostras de sementes. Nesse trabalho isso foi verificado pelas avaliações dos níveis de Pi após 12 h e 48 h, de P após 12 h, 36 h e 48 h, de Ca após 24 h, 36 h e 48 h, de Mg após 36 h e 48 h e de K após 36 h e 48 h de germinação. / Most of the traditional methods used for seed vigor evaluation are qualitative and, as such, prone to errors and results misinterpretation. Quantitative methods may constitute more reliable alternatives. The aim of this work was to verify if the concentrations of some minerals stored in the seeds and made available during the initial stages of the germination process constitute sensitive and reliable indicators of the level of corn seed vigor. Twenty seed lots were evaluated by means of the germination, electrical conductivity, cold and seedling field emergence tests. Additionally, the concentrations of inorganic phosphorus, phosporus, calcium, potassium and magnesium at 12 h, 24 h, 36 h and 48 h after the initiation of the germination process were also evaluated by means of the injection analysis in flow (FIA) and the spectrometry of optic emission coupled to plasma of induced argon (ICP-OES) techniques. For these analyses grinded seed samples were extracted with water at 95ºC, agitated for 30 minutes and centrifuged . It was concluded that the concentrations of Pi, P, Ca, Mg and K, extracted by the warm water method, in hybrid corn seeds after certain stages of the germination process, allowed the rating the of seed lots in a way similar to that obtained with the results of several other seed vigor tests. Specifically, this was achieved by evaluating the concentratrions of Pi after 12 h and 48 h, of P after 12 h, 36 h and 48 h, of Ca after 24 h, 36 h and 48 h, of Mg after 36 h and 48 h and of K after 36 h and 48 h after the beginning of the germination process.

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