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Ecossistemas de inovação e empreendedorismo: uma contribuição de análise na Rede AGROINNCUBA / Ecosystems of innovation and entrepreneurship: a contribution of qualitative analysis in the AGROINNCUBA NetworkAraujo, Níddia Mari Alves de 14 December 2018 (has links)
Visando o crescimento de empresas de base tecnológica, nota-se um movimento de cooperação entre Universidades, incubadoras de empresas, parques científicos e outros segmentos da sociedade nacional e internacional, com o objetivo de conectar e estimular redes de conhecimento para que o empreendedorismo seja fomentado de forma eficiente e proporcione a geração de empresas estruturadas e sadias a médio e longo prazo. O principal objetivo desse trabalho foi buscar contribuir com o estudo de como são gerados os ambientes chamados de ecossistemas de inovação, uma vez que o foco esteve voltado para uma pesquisa qualitativa, através da análise de depoimentos, de parte dos atores envolvidos em estudo de caso ligado à rede internacional de incubadoras e parques científicos/tecnológicos do sistema agroalimentar, denominada AGROINNCUBA e apoiada pelo Programa CYTED. Após a análise e observação dos discursos dos coordenadores e responsáveis pelas incubadoras de empresas vinculadas à AGROINNCUBA, pôde-se perceber que o fomento do empreendedorismo de fato ocorre no ecossistema a que incubadoras de empresas e parques estão inseridos. Ao final, foram confirmadas as hipóteses iniciais, uma vez que: a) o estudo de caso sugere que as incubadoras e parques científicos e ou tecnológicos da rede constituem parte de um ecossistema de inovação e que a o vínculo com centros de pesquisa e universidades mostrou-se vital para o seu bom funcionamento e, b) que a Rede AGROINNCUBA é formada por um conjunto de membros mais maduros e outro conjunto com membros ainda em consolidação. A interação entre esses dois grupos foi considerada saudável e produtiva no sentido de se buscarem processos de evolução e compartilhamento de curvas de experiências. / Aiming at the growth of technology-based companies, there is a movement of cooperation between universities, business incubators, science parks and other segments of national and international society, with the objective of connecting and stimulating knowledge networks so that entrepreneurship is fostered efficiently and provide the generation of structured and healthy companies in the medium and long term. The main objective of this work was to contribute to the study of how the so-called ecosystems of innovation are generated, once the focus was on a qualitative research, through the analysis of statements, on the part of the actors involved in a case study linked to the international network of incubators and science / technology parks of the agro-food system, named AGROINNCUBA and supported by the CYTED Program. After analyzing and observing the speeches of the coordinators and managers of the incubators of companies linked to AGROINNCUBA, it was possible to see that the promotion of entrepreneurship actually occurs in the ecosystem to which business incubators and parks are inserted. In the end, the initial hypotheses were confirmed, since: a) the case study suggests that incubators and science and technology parks in the network are part of an innovation ecosystem with strong links with research centers and universities. This connection was vital to the genesis and its proper functioning and, b) that the AGROINNCUBA Network is formed by a group of more mature members and another group with members still in consolidation. The interaction between these two groups was considered healthy and productive in order to look for processes of evolution and sharing of experience curves.
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MIGRAÇÃO, ESTABILIZAÇÃO E SATURAÇÃO DE CARBONO EM SISTEMAS DE MANEJO DO SOLO EM REGIÃO SUBTROPICAL E TROPICAL / CARBON MIGRATION, STABILIZATION AND SATURATION IN TILLAGE SYSTEMS FROM SUB- AND TROPICAL REGIONSBriedis, Clever 16 December 2015 (has links)
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Previous issue date: 2015-12-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / No till system (NT), associated to crop rotations with high and varied residues input, has been a very important tool to restore the soil organic carbon (C) stock depleted by long-term soil tillage, like conventional till (CT). However, there is no clear understanding about the potential to soil accumulate C, especially for high weathered soils. It was hypothesized that continuous residue input and less macroaggregation turnover in NT promote greater C accumulation and stabilization, which is the direction to reach the C saturation potential. Furthermore, it was hypothesized that SOC-poor deep soil layers have greater potential to extra C accumulation than at surface layers, and that the nutrient scarcity could be a drive force to C accumulation in subsoil. Therefore, the objectives of this study were: (i) improve the knowledge regarding the mechanisms that govern the C stabilization in different tillage systems (NT vs. CT) and the potential to these tillage systems accumulate C; (ii) evaluate the C stabilization in soil layers with different C saturation deficits and; (iii) assess the C-residue migration into soil organic matter (SOM) fractions in a laboratory incubation experiment. Results showed greater C accumulation in NT than that in PC, both in labile and bound to minerals SOM fractions. Additionally, the bound to minerals SOM fraction fitted to saturation model (asymptotic) for all three sites and indicated that actual soil C is far from the estimated potential to C accumulation. The incubation experiment showed greater CO2-C emission in the 0-20 than that in the 40-100 cm layer. It was related to greater labile SOC, and better fertility attributes in the surface layer, which promoted greater microbial activity. Besides, the C-residue conversion into soil C was greater in the surface soil layer, indicating that the soil microbiota in this layer was more efficient in C cycling. The low pH and the nutrient scarcity of P, Ca2+ e Mg2+ in the 20-40 and 40-100 cm layer were the driving force decreasing microorganism activity and thus, limiting C conversion in deep soil layers. Labile SOM fraction had greater accumulation in the 0-20 cm layer, as a response to a smaller C saturation deficit in this layer. However, C in bound to minerals SOM fraction was specially accumulated in the 20-40 and 40-100 cm layers, indicating that C saturation deficits in deep soil layers stimulate C accumulation in more stabilized SOM fractions. All three sites showed high C accumulation capacity, and the C saturation in the SOM fraction bound to mineral for all 0-20 cm layer will be in 104, 103 and 63 years for Ponta Grossa, Londrina and Lucas do Rio Verde, respectively. Overall sites, C accumulation potential followed: native vegetation > NT > CT. / O sistema plantio direto (PD), fundamentado na rotação de culturas com elevada e variada adição de resíduos, tem sido uma estratégia muito importante para a recuperação dos estoques de carbono (C) orgânico do solo perdidos em decorrência do manejo inadequado do solo. Todavia, ainda são escassas as informações a respeito do potencial máximo que os solos, especialmente os altamente intemperizados, possuem em acumular C. A hipótese desse trabalho foi que a adição constante de resíduos e a manutenção dos macroagregados no PD promove o acúmulo e maior estabilização de C no solo, tornando-se assim, o caminho para atingir o potencial de saturação. Preconizamos também, que as camadas mais profundas do solo possuem maior potencial em armazenar C e esse acúmulo pode ser controlado pela escassez de nutrientes. Dessa forma, os objetivos desse trabalho foram: (1) entender os mecanismos que governam a estabilização e o potencial de acúmulo de C em solos sob PD comparados ao preparo convencional (PC) em experimentos sob sistemas de manejo do solo de longa duração; (2) avaliar a estabilização de C em camadas de solo que apresentam diferentes déficits de saturação de C em experimento de incubação a partir de amostras de solos dos tratamentos sob PD; (3) avaliar a migração do C adicionado via resíduo para diferentes frações da matéria orgânica do solo (MOS). O estudo foi realizado em experimentos de longa duração em sistemas de manejo. Os locais selecionados para o estudo foram Ponta Grossa (PG), Londrina (LDN) e Lucas do Rio Verde (LRV). O tempo de implantação dos experimentos de manejo no momento da coleta de solo era de 29, 23 e 8 anos para PG, LDN e LRV, respectivamente. Todos os solos foram classificados como Latossolos e o teor de argila de cada área era de 650, 710 e 402 g kg-1 em PG, LDN e LRV, respectivamente. Os resultados evidenciaram que o PD, em relação ao PC, proporcionou maior acúmulo de C, tanto em frações lábeis da MOS quanto nas associadas aos minerais. Além disso, a fração associada aos minerais se ajustou ao modelo de saturação de C nos três locais de estudo e foi constatado que os níveis atuais de C estão distantes da saturação. O experimento de incubação mostrou maior emissão de C-CO2 na camada de 0-20, comparada com a de 40-100 cm, e este fato está associado ao maior conteúdo de C lábil e ao maior nível da fertilidade da camada superficial do solo, promovendo a maior atividade microbiana. A eficiência da conversão do C derivado do resíduo cultural em C do solo foi superior na camada superficial, indicando que a microbiota do solo nessa camada foi mais eficaz na ciclagem do C. A escassez dos nutrientes P, Ca2+ e Mg2+ nas camadas de 20-40 e 40 a 100 cm de profundidade atuaram como um fator controlador da atividade microbiana resultando em menor eficiência na conversão em C do solo quando comparada com a camada de 0-20 cm de profundidade. A fração lábil da MOS teve maior acúmulo de C na camada de 0-20 cm, em resposta ao menor déficit de saturação nessa camada, além do melhor nível de fertilidade do solo nesta camada favorecendo o acúmulo de C nas frações mais sensíveis da MOS. Entretanto, na fração associada aos minerais, o acúmulo de C foi superior nas camadas de 20-40 e 40-100 cm de profundidade, demonstrando que o déficit de saturação de C em camadas profundas favorece o acúmulo de C nas frações mais estabilizadas. Os solos dos três locais estudados demonstraram elevada capacidade de acúmulo de C, e a estimativa para a completa saturação de C na fração associada aos minerais na camada de 0-20 cm, é 104, 103 e 63 anos, para Ponta Grossa, Londrina e Lucas do Rio Verde, respectivamente. Nos três locais de estudo, o potencial máximo de acúmulo de C seguiu a ordem: vegetação nativa > PD > PC.
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Empreendimentos econômicos solidários: sistematização da experiência de formação da incubadora Co-Labora / Solidary economic enterprises: systematization of the formation experience of the Co-Labora incubatorBellissimo, Daniel Yacoub 07 November 2016 (has links)
As incubadoras universitárias têm se constituído nas principais universidades brasileiras desde o fim da década de 1990. Elas trabalham dentro da linha de economia solidária, no desenvolvimento de cooperativas populares ou empreendimentos econômicos solidários e, durante esse trabalho, enfrentam diversos desafios. Um deles é conseguir contribuir com tais empreendimentos em suas dimensões empresa - uma gestão atenta à qualidade do produto ou serviço, aos processos e operações para sua maior eficiência, à sua inserção no mercado e à melhor organização dos seus recursos financeiros e não-financeiros; e associativa - uma gestão atenta à importância de sua missão social, à manutenção de sua vitalidade associativa, aos processos para que a democracia prevaleça e ao seu enraizamento na comunidade e no seu setor de atuação de forma cooperativa. Este trabalho avaliou o desenvolvimento de uma incubadora recém-formada, nos seus dois anos iniciais, na USP campus Ribeirão Preto, com a análise voltada para sua estrutura, equipe, metodologia e atuação junto aos empreendimentos incubados, percebendo as condições favorecedoras e desafiadoras de uma incubação que de fato contribua com ambas as dimensões. O método utilizado foi o de sistematização de experiências, considerado apropriado para construir a linha do tempo da incubadora, constituir os principais marcos e eixos do trabalho realizado e promover a reflexão crítica dos fatos e experiências levantados. Os resultados indicam que houve dificuldade na integração entre as dimensões empresa e associativa na atuação junto aos grupos incubados, com destaque ou maior ênfase para uma dimensão ou outra ao longo do tempo, devido principalmente aos acúmulos da equipe com maior participação naquele momento. Além disso, a percepção dos membros da incubadora foi avaliada por meio de entrevistas estruturadas, e indicou que alguns creditam tal enfoque em uma dimensão ou na outra por conta das demandas do grupo naquele momento, outros para qual fosse a constituição e formação da equipe mais próxima do trabalho e ainda porque indivíduos específicos de cada grupo pudessem demandar abordagens distintas. Por fim, concluiu-se que a incubadora produziu efeitos positivos e negativos devido a essa dificuldade no equilíbrio entre ambas as dimensões nos trabalhos realizados e que, com essa informação, as incubadoras universitárias pelo país podem buscar maior integração entre elas e, assim, atingir através de seus trabalhos com os empreendimentos solidários maior eficiência econômica e felicidade humana. / The university incubators have been constituted in the main Brazilian universities since the end of the 1990s. They work within the solidarity economy line, in the development of popular cooperatives and solidarity economy enterprises, and during this work, face several challenges. One of them is their capability to achieve contributions to the solidarity enteprises in their company dimension - a careful management to product quality or service, processes and operations to their greater efficiency, its insertion in the market and the best organization of its financial and non-financial resources; and their associative dimension - a management attentive to the importance of its social mission, the maintenance of its associative vitality, processes that makes democracy prevails and its rootedness in the community and its industry, in a cooperative manner. This study evaluated the development of a newly formed incubator in its first two years, at USP campus Ribeirao Preto, with focused analysis of its structure, staff, methodology and performance with the incubated enterprises, realizing that favor and challenging conditions of an incubation that actually contribute to both dimensions. The method used was the systematization of experiences, considered appropriate to construct the time line of the incubator, constitute major milestones and axes of the work and promote critical reflection of the facts and experiences raised. The results indicate that there were difficulties in integration between the company and associative dimensions in performance with the incubated groups, highlighting or with greater emphasis on one dimension or another over time, mainly due to the accumulations of the team with greater participation at that time. Moreover, the perception of the members of the incubator was evaluated through structured interviews, and indicated that some credited an approach focused in one dimension or the other because of the demands of the group at that time, others for which was the establishment and training of staff nearest to the work and because specific individuals of each group might require different approaches. Finally, it was concluded that the incubator has had positive and negative effects due to the difficulty in balancing both dimensions in the performed work, and with this information, the university incubators around the country may seek greater integration between them and thus achieve, through their work with solidarity enterprises, greater economic efficiency and human happiness.
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Mineralização de fósforo do adubo verde e sua absorção por plantas de arroz / Mineralization of green manure phosphorus and its absorption by rice plantsMarsola, Tatiana 14 March 2008 (has links)
Em sistemas de plantio direto, o material vegetal incorporado libera fósforo solúvel no solo, porém, sua absorção por plantas subseqüentes ainda é pouco conhecida. Parte do fósforo nos tecidos vegetais está na forma de compostos insolúveis, que precisam ser mineralizados para serem absorvidos pelas plantas. Os objetivos deste trabalho foram estabelecer a melhor época de aplicação de 32P para marcação de plantas de adubo verde; determinar as formas de P nas plantas; determinar as principais formas de fósforo no solo após a incorporação de diferentes espécies de adubo verde; estimar a eficiência dos adubos verdes no fornecimento de P para plantas de arroz, e determinar a relação entre as formas de P nas plantas de adubo verde e sua mineralização no solo. Os experimentos foram conduzidos em duas etapas. Na Etapa 1 foram marcadas com 32P plantas de aveia-preta, milheto e nabo forrageiro na semeadura e aos 14, 28 e 42 dias. Estas plantas foram incubadas e utilizadas como adubo verde no cultivo de arroz. As plantas de arroz apresentaram eficiência de utilização de P semelhantes para adubos verdes marcados até 28 dias, podendo ser utilizada uma atividade 75% menor para marcação dessas espécies. Na etapa 2 foram cultivadas plantas de aveia-preta, crotalária e nabo forrageiro marcadas com 32P aos 14 dias. Foi verificado que a maioria do P nas plantas está na forma solúvel, correspondendo em média 67% do 32Pt. Essas plantas foram incubadas por 20, 40 e 60 dias e cultivadas plantas de arroz. A eficiência de utilização do P proveniente de adubo verde foi maior para incubação por 20 e 60 dias, diminuindo consideravelmente para incubação por 40 dias. Foram determinadas as frações de P no solo incubado com adubo verde nos diferentes períodos de incubação, utilizando o método de Hedley. A fração Pi-resina e P-NaHCO3, que correspondem ao P-lábil, apresentaram as maiores atividades específicas, demonstrando que a maior parte do P solúvel do adubo verde são encontrados nessas frações. A fração Po-NaOH apresentou as maiores concentrações de P, enquanto as menores foram encontradas na fração P-HCl / In no-tillage systems, plant materials incorporated into soil release soluble phosphorus, but its absorption by subsequent plants is not completely clarified. A fraction of phosphorus in vegetal tissues is in the form of insoluble species, which require mineralization to be absorbed by plants. The aims of this work were to establish the best period for 32P application for green manure labeling; to determine the forms of P in plants and in soil after incorporation of different green manures; to estimate the efficiency of green manures for supplying phosphorus to rice plants and to determine the relationship between the P species in green manure and their mineralization in soil. The experiments were carried out in two steps. In the first, plants of black oat, millet and turnip were labeled with 32P at sowing and after 14, 28 and 42 days. These plants were incubated and used as green manure for rice plants. The rice plants showed similar utilization efficiencies of P form green manure plants labeled up to 28 days, making possible the use of a 75% lower activity to label these plants. In step two, black oat, sunnyhemp and turnip plants labeled with 32P after 14 days from sowing were grown. It was verified that the more significant fraction of P in plants is in the soluble form, corresponding in average 67% of 32Pt. These plants were incubated for 20, 40 and 60 days before culturing rice plants. The utilization efficiency of P from green manure sources was higher when the material was incubated for 20 and 60 days, being considerably reduced for 40 days incubation. The P-fractions in the soil incubated with green manure in different periods were determined by the Hedley method. The Pi-resin and P-NaHCO3 fractions, which correspond to labile P, showed the highest specific activities, because the most significant part of the soluble P was found in these fractions. The Po-NaOH fraction showed the highest concentrations of P, while the lowest amounts were in the P-HCl fraction
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Hibridização in situ em espermatozóides bovinos tratados com DNA exógeno: estudo experimental / In situ hybridization in bovine sperm treated with exogenous DNA: an experimental study.Cavalcanti, Paulo Varoni 17 December 2010 (has links)
Muitas das técnicas utilizadas para gerar animais transgênicos são caras e laboriosas. Neste contexto, a transferência gênica mediada por espermatozóides (TGME) pode ser uma alternativa para a produção em larga escala de animais transgênicos. Estudos de SMGT têm seu foco no número de cópias de DNA incorporada pelo espermatozóide. Por isso, há pouca informação disponível sobre como as moléculas de DNA se comportam durante o processo de fecundação e quais os efeitos dos protocolos de TGME sobre a célula espermática. Neste sentido, com o objetivo de avaliar a existência de sitio de integração preferencial das moléculas exógenas de DNA no genoma hospedeiro, utilizamos a hibridização in situ para acompanhar a veiculação do transgene durante o processo de fecundação. Foram avaliadas as membranas acrossomais, plasmática e potencial de membrana mitocondrial de espermatozóides submetidos a TGME. Para isso, o sêmen de três diferentes touros foram submetidos ao gradiente de Percoll 45-90%. As células viáveis foram incubadas com o vetor recombinante pCX-EGFP (0, 250, 500 ou 1000ng/106 células) seguidas ou não de eletroporação (300v, 35µF e 0,25ms). Os espermatozóides tratados foram utilizados para a produção in vitro de embriões. Os embriões foram cultivados por sete dias até o estágio de blastocisto. Espermatozóides e embriões produzidos in vitro foram submetidos ao ensaio de hibridização in situ, com metodologia descrita Whyte et al. (2000). O potencial de membrana mitocondrial (PMM), integridade de membrana acrossomal (MA) e plasmática (MP) foram avaliados por citometria de fluxo (Guava Technologies, Hayward, CA, USA) utilizando as sondas fluorescentes JC1, FITC-PSA e PI (Molecular Probes), respectivamente. Os dados foram analisados pelo teste paramétrico ANOVA (teste LSD) usando o programa estatístico SAS for Windows, com nível de significância de 5%. A hibridização in situ não foi possível em espermatozóides bovinos, pois não houve hibridação da sonda controle. Blastocistos oriundos de espermatozóides incubados com DNA exógeno apresentaram integração de forma difusa, embriões oriundos de espermatozóides eletroporados apresentaram integração pontual. As diferentes concentrações de DNA não exerceram efeitos deletérios nas MP ou PMM, a adição de 500ng de DNA causou aumento de lesão na MA (p<0,05). A eletroporação não afeta a MP e MA, mais apresenta grande efeito no PMM causando redução da função mitocondrial. Este estudo conclui que maiores esforços são necessários para elucidar o comportamento das moléculas exógenas de DNA durante o processo de fecundação e quais são os efeitos da TGME sobre a célula espermática. / Most techniques used to produce transgenic animals are laborious and expensive. In this manner, sperm mediated gene transfer (SMGT) may be a viable alternative for long-scale production of transgenic animals. Many SMGT studies have focused the DNA internalization and number of DNA copies incorporated by spermatozoa. However, limited data is available about how foreign DNA molecules behave during fertilization and the direct effects of the SMGT technique on sperm cells. Hence, in order to monitor the existence of preferential integration sites by the exogenous DNA at the host genome, in situ hybridization was used to track the transgene conveyance during in vitro fertilization. In addition, acrosome and plasmatic membrane integrity and mitochondrial membrane potential of sperm cells subjected to SMGT were assessed. Briefly, thawed semen from three different bulls was submitted to a 45- 90% Percoll gradient. Viable cells were incubated with recombinant PCX-EGFP vector (0, 250, 500 or 1000ng/106 sperm cells) or incubated and electroporated (300V, 35µF and 0.25ms). Treated sperm cells were then used for in vitro production of embryos. Embryos were in vitro cultured for 7 days until blastocyst stage. Treated spermatozoa and in vitro produced blastocysts were submitted to in situ hybridization assay, as described by Whyte et al. (2000). The mitochondrial membrane potential (MMP), acrosomal membrane (AM) and plasmatic membrane (PM) integrity were assessed by flow cytometry (Guava Technologies, Hayward, CA, USA) using JC1, FITC-PSA and PI probes (Molecular Probes), respectively. Data were analyzed by parametric ANOVA (LSD test) using SAS for Windows software, at a 5% level. The transgene was not observed at the bovine spermatozoa because the control probe could not be hybridized. In situ hybridization revealed that blastocysts produced from incubated sperm cells had a diffuse foreign DNA integration while blastocysts produced from electroporated sperm cells had a punctual DNA integration. No deleterious effects of exogenous DNA concentrations on PM or MMP were observed. However, the addition of 500ng of exogenous DNA caused sperm AM injury (P<0.05). Electroporation did not affect PM or AM integrity, but it had a great effect on MMP, which may cause a reduction of mitochondrial function. This study suggest that more efforts are needed to elucidate the behavior of exogenous DNA during fertilization and the effects of SMGT in bovine sperm cells.
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Recomendação de calagem para alguns solos do Estado do AmazonasBatista, Iza Maria Paiva 30 September 2014 (has links)
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Previous issue date: 2014-09-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Upland soils Amazonas state is characterized by having pH and Al3+ at
levels that limit the good yields. The objective of this study was to evaluate the
chemical changes in function in soils of the addition of different levels of limestone and
estimate quantities needed corrective to reach pH arable. We used a completely
randomized block design with three replications. The treatments consisted of a factorial
3 x 7 by matching three textural classes (medium texture, clay, and much clay) with
seven levels of limestone (0, 1.0, 2.0, 4.0, 6.0, 8, 0 to 10 t ha-1). After 56 days of
incubation, the pH values were determined in water; this was plotted versus liming and
adjusted polynomial regression models, to determine the quantity of lime necessary to
achieve pH 5.5; 6.0 and 6.5. At that time, it was determined the Al3+ content, Ca2+,
Mg2+, K and H + Al and from these values calculated the base saturation (V%). The
efficiency of liming by incubation curve method was evaluated in experiments
conducted in a greenhouse through the effect of different rates of lime in the production
of MSPA and MSR in the corn and bean crops. The treatments were arranged in a
completely randomized design in a factorial 2 x 7, combining two soil (Ultisol and
Oxisol) and seven levels of limestone (0, 1.0, 2.0, 4.0, 6.0, 8.0 and 10 t ha-1), with four
replications. The data MSPA, MSR and content of P, K, Ca, Mg, Zn, Fe, Mn and Cu in
the shoots were adjusted regression models and then estimated the limestone,
corresponding to the ESM. The soil showed high significance indices with the amount
of lime to raise the pH of the soil, and the levels of 0.3; 2.2 and 4.0; 2.6; 4.4 and 6.1;
2.2; 4.0 and 5.8 t ha-1 of lime in medium textured soils, clayey and much clayey are
recommended to achieve the pH 5.5; 6.0 and 6.5, respectively. The recommendation of
1.5; 2.6 to 2.2 t ha-1 was sufficient to reduce Al3+ and the doses of 3.7; 4.7 and 4.6 t ha-
1 increasing the saturation to levels appropriate for crop development, corresponding to
water pH around 6.3; 6.0 and 6.5 in medium textured soils, clayey and much clayey,
respectively. The quantities of limestone corresponding to maximum economic yield
MSPA and MSR both corn as the beans are close to the amount recommended by the
method of incubation curve required to achieve the pH acceptable for cultivation and
these doses have not reduced below the deficiency of the content absorption during the
first 60 days of cultivation. / Os solos de terra firme do estado do Amazonas caracterizam-se por
apresentar pH e Al3+ em níveis que limitam o bom rendimento das culturas. Objetivouse
com o presente estudo, avaliar as modificações químicas nos solos em função da
adição de diferentes níveis de calcário e estimar quantidades necessárias de corretivo
para atingir pH agricultável. Utilizou-se um delineamento em blocos inteiramente
casualizados, com três repetições. Os tratamentos foram constituídos de um fatorial 3 x
7, combinando três classes texturais (textura média, argilosa e muito argilosa) com sete
doses de calcário (0; 1,0; 2,0; 4,0; 6,0; 8,0 e 10 t ha-1). Após 56 dias de incubação,
determinaram-se os valores de pH em água, este foi plotado versus doses de calcário e
ajustados a modelos de regressão polinomial, para determinar a quantidade de calcário
necessária para atingir os valores de pH 5,5; 6,0 e 6,5. Nessa época, determinaram-se os
teores de Al3+, Ca2+, Mg2+, K e H+Al e a partir desses valores calculou-se o índice de
saturação por bases (V%). A eficiência da recomendação de calagem pelo método da
curva de incubação foi avaliada em experimentos conduzidos em casa de vegetação por
meio do efeito de diferentes doses de calcário na produção de MSPA e MSR nas
culturas do milho e feijão. Os tratamentos foram dispostos em delineamento
inteiramente casualizado num esquema fatorial 2 x 7, combinando dois solos (Argissolo
e Latossolo) e sete doses de calcário (0; 1,0; 2,0; 4,0; 6,0; 8,0 e 10 t ha-1), com quatro
repetições. Os dados de MSPA, MSR e conteúdo de P, K, Ca, Mg, Zn, Fe, Mn e Cu na
parte aérea das plantas, foram ajustados a modelos de regressão e posteriormente
estimadas as doses de calcário, correspondentes à MEE. Os solos estudados revelaram
altos índices de significância com a necessidade de calcário para elevar o pH dos solos,
sendo as doses de 0,3; 2,2 e 4,0; 2,6; 4,4 e 6,1; 2,2; 4,0 e 5,8 t ha-1 de calcário nos solos
de textura média, argilosa e muito argilosa são recomendadas para atingirem o pH 5,5;
6,0 e 6,5, respectivamente. A recomendação de 1,5; 2,6 e 2,2 t ha-1 foi suficiente para
reduzir o Al3+ e as doses de 3,7; 4,7 e 4,6 t ha-1 elevando a saturação por bases a níveis
adequados para o desenvolvimento das culturas, correspondendo a pH em água em
torno de 6,3; 6,0 e 6,5 nos solos de textura média, argilosa e muito argilosa,
respectivamente. As quantidades de calcário correspondente ao máximo rendimento
econômico de MSPA e MSR tanto no milho quanto no feijão aproximam-se da
quantidade recomendada pelo método da curva de incubação necessária para atingir o
pH aceitáveis para cultivo e essas doses não reduziram abaixo do teor de deficiência a
absorção durante os 60 dias de cultivo.
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Étude expérimentale et intégrative des coûts et bénéfices de la viviparité chez le lézard vivipareBleu, Josefa 02 November 2011 (has links) (PDF)
La viviparité, qui consiste à mettre au monde directement des jeunes vivants, a évolué de nombreuses fois à partir de l'oviparité, qui consiste à pondre des oeufs, en particulier chez les lézards et les serpents (les squamates). Ce groupe est celui où l'on observe le plus grand nombre d'évolutions indépendantes de la viviparité, ainsi que des évolutions récentes et à des niveaux taxonomiques faibles. Le lézard vivipare est une des rares espèces au sein de laquelle l'oviparité et la viviparité coexistent. J'ai donc utilisé cette espèce pour mon étude sur les coûts et les bénéfices de la viviparité. Je me suis d'abord intéressée aux ajustements de l'investissement dans la reproduction ainsi qu'aux coûts de la gestation. J'ai observé une absence d'ajustement post-ovulatoire de la taille de portée, de la masse de portée et de la masse du jeune. Cependant, j'ai montré que les femelles ajustent ces paramètres en fonction de leur environnement pendant la vitellogenèse, ainsi qu'en fonction de leur corpulence et de leur date de mise bas de l'année passée. J'ai ensuite étudié les coûts de la gestation de manière expérimentale, en contrôlant les accouplements, en manipulant la taille de portée, et en comparant des femelles ovipares à des femelles vivipares. Ces études ont mis en évidence, selon le contexte, des effets de la gestation sur le système immunitaire, sur le comportement de thermorégulation, sur l'endurance, et sur la perte de poids des femelles ; mais pas d'effet sur leur survie après la mise bas. L'étude comparative a montré que les coûts de la reproduction sont plus importants pour les femelles ovipares que les vivipares avant la gestation. Par ailleurs, la gestation est une période non seulement associée à des coûts mais aussi à des effets maternels. J'ai montré que la croissance des jeunes après la naissance dépend de la taille de portée pendant la gestation. Cependant, comme c'est souvent le cas, le mécanisme de cet effet maternel n'est pas connu. Afin de mettre en évidence les facteurs à l'origine des effets maternels, j'ai développé une approche expérimentale qui repose sur l'incubation in vitro d'embryons de lézards vivipares. Les résultats préliminaires sont prometteurs étant donné que ce processus permet d'obtenir des jeunes vivants. Finalement, j'ai montré l'existence d'effets de l'âge grand-maternel chez les lézards vivipares. Il s'agit de la première mise en évidence d'effets de l'âge grand-maternel en populations naturelles.
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C5a Receptor Expression in Severe Sepsis and Septic ShockFurebring, Mia January 2005 (has links)
<p>In patients with sepsis, the activation of the cascade systems, for example the complement system with the generation of C5a, is followed by a state of immunosuppression with impaired bactericidal capacity caused by suppression of the neutrophil granulocytes. To inhibit the C5a-induced systemic inflammatory and the following anti-inflammatory responses, different anti-C5a strategies have been successful in experimental models of sepsis. In animals and in healthy volunteers after injection of lipopolysaccharide (LPS), an up-regulation of the C5a receptor (C5aR) has been reported. Before designing clinical studies, it was of importance to increase the knowledge of C5a and C5aR regulation in humans. </p><p>At the time when the diagnosis of severe sepsis or septic shock can be established clinically, granulocyte C5aR expression, analysed by flow cytometer, was shown to be reduced, whereas monocyte C5aR expression was unchanged. There was a correlation between granulocyte C5aR expression and the severity of disease, as measured by the APACHE II score. </p><p><i>Ex vivo</i> incubation of whole blood with LPS resulted in a reduction in granulocyte C5aR expression. Such a reduction was not found in isolated cells, indicating that the effect was mediated via plasma factors, such as C5a, IL-8 and TNF-α which all were shown to reduce C5aR expression <i>ex vivo</i>.</p><p>Although there was a trend between chemotaxis, as measured by migration in a modified Boyden chamber, and C5aR expression on granulocytes from patients with severe sepsis or septic shock or from healthy individuals, the correlation failed to reach statistical significance.</p><p>It is concluded that granulocyte C5aR expression is affected by several plasma factors and that a reduction is clinically evident at the time of the sepsis diagnosis. Reduced granulocyte C5aR expression is associated with an impaired chemotaxis but does not alone limit the chemotactic response.</p>
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C5a Receptor Expression in Severe Sepsis and Septic ShockFurebring, Mia January 2005 (has links)
In patients with sepsis, the activation of the cascade systems, for example the complement system with the generation of C5a, is followed by a state of immunosuppression with impaired bactericidal capacity caused by suppression of the neutrophil granulocytes. To inhibit the C5a-induced systemic inflammatory and the following anti-inflammatory responses, different anti-C5a strategies have been successful in experimental models of sepsis. In animals and in healthy volunteers after injection of lipopolysaccharide (LPS), an up-regulation of the C5a receptor (C5aR) has been reported. Before designing clinical studies, it was of importance to increase the knowledge of C5a and C5aR regulation in humans. At the time when the diagnosis of severe sepsis or septic shock can be established clinically, granulocyte C5aR expression, analysed by flow cytometer, was shown to be reduced, whereas monocyte C5aR expression was unchanged. There was a correlation between granulocyte C5aR expression and the severity of disease, as measured by the APACHE II score. Ex vivo incubation of whole blood with LPS resulted in a reduction in granulocyte C5aR expression. Such a reduction was not found in isolated cells, indicating that the effect was mediated via plasma factors, such as C5a, IL-8 and TNF-α which all were shown to reduce C5aR expression ex vivo. Although there was a trend between chemotaxis, as measured by migration in a modified Boyden chamber, and C5aR expression on granulocytes from patients with severe sepsis or septic shock or from healthy individuals, the correlation failed to reach statistical significance. It is concluded that granulocyte C5aR expression is affected by several plasma factors and that a reduction is clinically evident at the time of the sepsis diagnosis. Reduced granulocyte C5aR expression is associated with an impaired chemotaxis but does not alone limit the chemotactic response.
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Comparative reproductive strategies between long-tailed ducks and king eiders at Karrak Lake, Nunavut: use of energy resources during the nesting seasonLawson, Shona Louise 21 September 2006
Energy demands can be particularly high in arctic-nesting birds that face harsh, unpredictable conditions during the breeding season. Consequences of these demands, particularly energy-partitioning during egg laying and incubation, are fundamentally important for arctic nesters. This study investigated differences in breeding strategies between Long-tailed Duck (<i>Clangula hyemalis</i>) and King Eider (<i>Somateria spectabilis</i>) in the central Canadian arctic. The focus was on ecological variables and influences of variation in nutrient resources used during incubation and egg production. Research was done at Karrak Lake, Nunavut, where both species nest sympatrically at relatively high densities, permitting comparative research about breeding strategies.<p>This study used stable-carbon (d13C) and nitrogen (d15N) isotope analysis to investigate origins and allocation of endogenous (stored) and exogenous (external) nutrients used in egg production. Remote temperature sensors were placed in nests to estimate and compare incubation rhythms and gain insight into capital and income incubating strategies of both species. Results suggest that breeding Long-tailed Ducks and King Eiders used a mixed breeding strategy, that is they relied on both exogenous and endogenous resources for reproduction. Close correspondence between d13C and d15N values of egg components and potential diet items indicated that King Eiders allocated exogenous nutrients for egg production (albumen 98.1%, yolk protein 96.8%, whole yolk 98.4%, and yolk lipids 84%). Female King Eiders relied on endogenous nutrients for incubation, as evidenced by high incubation constancy (96%). Conversely, the range of d13C values in components of Long-tailed Duck eggs and d13C values of diet items suggested that although some females allocated endogenous reserves for egg production, most females allocated exogenous resources for egg production (albumen 98.5%, yolk protein 78.3%, whole yolk 84.9%, and yolk lipids 38.3%). Long-tailed Duck females had an 84% incubation constancy, suggesting less reliance on endogenous nutrients for incubation than was estimated for female King Eiders. Knowledge about the relative importance of endogenous reserves and exogenous nutrients for egg production and incubation may help direct management decisions to specific winter/staging and or breeding areas used by King Eiders and Long-tailed Ducks.
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