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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.
261

Turismo e patrim?nio cultural: pol?ticas, a??es e interven??es no munic?pio de Natal-RN / Tourism and cultural heritage: political actions and intervention in Natal-RN

Morais, Lucil?ia Lima de 29 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-04T12:39:41Z No. of bitstreams: 1 LucileiaLimaDeMorais_DISSERT.pdf: 4308046 bytes, checksum: fa947339f8c2b51271bb3170c84d1082 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-12T13:36:59Z (GMT) No. of bitstreams: 1 LucileiaLimaDeMorais_DISSERT.pdf: 4308046 bytes, checksum: fa947339f8c2b51271bb3170c84d1082 (MD5) / Made available in DSpace on 2017-07-12T13:36:59Z (GMT). No. of bitstreams: 1 LucileiaLimaDeMorais_DISSERT.pdf: 4308046 bytes, checksum: fa947339f8c2b51271bb3170c84d1082 (MD5) Previous issue date: 2016-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O estudo tem como objetivo principal compreender os fatores que tem dificultado na funcionaliza??o tur?stica do centro hist?rico de Natal entre os anos de 1976 a 2015, per?odo em que foram elaboradas relevantes pol?ticas p?blicas para a preserva??o do patrim?nio cultural brasileiro e que continham em seu discurso a valoriza??o tur?stica de bens culturais. A metodologia do trabalho foi baseada na an?lise das principais a??es e pol?ticas de turismo e de cultura que ocorreram no centro hist?rico de forma a entender se h? ou n?o uma intersec??o entres as pol?ticas p?blicas e refletir sobre as a??es deliberadas pelos diversos atores presentes na regi?o hist?rica da cidade. Foram realizadas entrevistas com representantes do poder p?blico local, iniciativa privada, sociedade civil e turistas por meio de roteiros de entrevistas n?o estruturados. Trata-se de um estudo transversal, de car?ter descritivo e explorat?rio, onde foi selecionada a t?cnica de an?lise de conte?do para o tratamento dos dados. Percebeu-se que as a??es de preserva??o, apesar de contemplar em seus objetivos a promo??o da atividade tur?stica em centros hist?ricos, n?o conseguem transpor a fase de inventaria??o e diagn?sticos ou se restringem a implanta??o de projetos de forma isolada e sem continuidade, estacionando em etapas consideradas preliminares na avalia??o de pol?ticas p?blicas. Observou-se tamb?m que n?o h? uma gest?o tur?stica do patrim?nio cultural e n?o existe uma a??o espec?fica de promo??o tur?stica do corredor cultural de Natal como ? realizado com o segmento de sol e praia. A ?rea j? est? dotada de projetos suficientes para a sua valoriza??o hist?rica, tur?stica e cultural, no entanto, o conflito de interesse entre os ?rg?os de preserva??o e demais secretarias, a burocracia e o desconhecimento da legisla??o espec?fica por parte dos formuladores de a??es na regi?o hist?rica ainda s?o os principais entraves para a funcionalidade tur?stica no centro hist?rico de Natal. / The main objective of the study is to understand the factors that have hampered the functionalisation of the historical center of Natal between 1976 and 2015, during which time relevant public policies for the preservation of the Brazilian cultural heritage were elaborated to cultural valurization. The methodology of the work was based on the analysis of the main actions and policies of tourism and culture that occurred in the historic center in order to understand whether or not there is an intersection between public policies and reflect on the deliberate actions of the various actors present in the historical region of the city. Interviews were conducted with representatives of local government, private sector, civil society and tourists through unstructured interviews. This is a cross-sectional, descriptive and exploratory study, where the content analysis technique was selected for the treatment of the data. It was noticed that preservation actions, although contemplating in their objectives the promotion of tourist activity in historical centers, can not transpose the inventory and diagnostic phase or are restricted to the implementation of projects in isolation and without continuity, partaking in stages considered preliminary in the evaluation of public policies. It was also observed that there is no tourism management of cultural heritage and there is no specific action of tourist promotion of the cultural corridor of Natal as it is carried out with the segment of sun and beach. The area is already endowed with sufficient projects for its historical, tourist and cultural valorization, however, the conflict of interest between the preservation agencies and other secretariats, the bureaucracy and the lack of knowledge of the specific legislation by the formulators of actions in the region historic are still the main obstacles to the tourist function in the historical center of Natal.
262

An?lise da cin?tica de oxig?nio e da frequ?ncia card?aca de recupera??o ap?s teste de esfor?o cardiopulmonar em obesas / Analysis of oxygen kinetics and heart rate recovery after cardiopulmonary exercise test in obese women

Lima, Davi Fialho Silva 19 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-04T22:45:45Z No. of bitstreams: 1 DaviFialhoSilvaLima_DISSERT.pdf: 7992805 bytes, checksum: c9ae57ed3d2a37526fb2c44c2d463bfd (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-14T00:07:17Z (GMT) No. of bitstreams: 1 DaviFialhoSilvaLima_DISSERT.pdf: 7992805 bytes, checksum: c9ae57ed3d2a37526fb2c44c2d463bfd (MD5) / Made available in DSpace on 2017-10-14T00:07:17Z (GMT). No. of bitstreams: 1 DaviFialhoSilvaLima_DISSERT.pdf: 7992805 bytes, checksum: c9ae57ed3d2a37526fb2c44c2d463bfd (MD5) Previous issue date: 2017-06-19 / Introdu??o: A capacidade funcional ? prejudicada pela obesidade e pode ser avaliada por testes f?sicos que examinam a a??o sincronizada dos sistemas cardiovascular, respirat?rio e musculoesquel?tico. O comportamento cardiovascular e respirat?rio, medido por FC (frequ?ncia card?aca) e cin?tica de oxig?nio, por exemplo, no per?odo de recupera??o do exerc?cio tem mostrado ser um bom indicador de sa?de cardiovascular, reestabelecimento de reservas energ?ticas e equil?brio auton?mico em saud?veis e cardiopatas. Entretanto, n?o se conhece o comportamento da cin?tica de oxig?nio e da FCR (FC de recupera??o) em obesos sem doen?a card?aca diagnosticada. Objetivo: Analisar o comportamento da cin?tica de oxig?nio e FCR e ap?s teste de esfor?o cardiopulmonar em obesas. Materiais e M?todos: Estudo observacional, transversal com 32 volunt?rias, analisadas no teste de esfor?o cardiopulmonar (TECP), alocadas por conveni?ncia nos grupos obesidade (GO, N=16) e n?o obesas (GNOB, N=16). Realizadas avalia??es cl?nica, antropom?trica e de adiposidade e espirom?trica inicial. O TECP cl?nico padr?o foi realizado usando protocolo de rampa individualizado, sendo tomadas as medidas ventilat?rias e metab?licas (breath-?by-?breath), com registro das vari?veis de interesse no repouso (2?) e 5? iniciais de recupera??o (3 minutos-?recupera??o ativa, 2 minutos-?recupera??o passiva). A cin?tica de recupera??o foi calculada por modelo de regress?o linear da curva de decl?nio do VO2 durante o primeiro minuto de recupera??o em fun??o do tempo (T? e VO2/t) e a frequ?ncia FCR obtida pela diferen?a da FC no pico do teste e a FC no primeiro minuto de recupera??o. Resultados: os grupos foram homog?neos quanto ? idade, altura e medidas espirom?tricas. Diferen?as significativas foram encontradas na FCR (p=0,041) e VO2pico (p<0,001) entre os grupos. A cin?tica do VO2 apresentou diferen?a significativa no T? de VO2 (p=0,003) e VO2/t (p=0,041). Observou-?se que o VO2pico (0,59), IMC (-?0,16) e CQ (0,18) justificam a vari?ncia do VO2/t em 72%. Foi atestada uma colinearidade negativa entre as medidas de adiposidade de CQ e IMC. Conclus?o: Obesos jovens t?m respostas lentificadas da cin?tica de recupera??o do VO2 e FC em rela??o a n?o obesas, sugerindo que obesos t?m preju?zo na restaura??o dos estoques energ?ticos ou circulat?rios no m?sculos perif?ricos e disfun??o auton?mica, e que tais altera??es podem contribuir para a instala??o de doen?as cardiovasculares e o aumento da taxa de morbi-?mortalidade nesta popula??o. / Introduction: Functional capacity is impaired by obesity and can be assessed by physical tests that examine a synchronized action of the cardiovascular, respiratory and musculoskeletal systems. Cardiovascular and respiratory behavior, measured by HR (heart rate) and oxygen kinetics, for example, during the period of exercise recovery has been considered as indicator of cardiovascular health, reestablishment of energy reserves and autonomic balance in healthy and patients with heart disease. However, the behavior of oxygen kinetics and HRR (recovery HR) in obese patients without diagnosed heart disease is not known. Aim: To analyze the pattern of oxygen kinetics and HRR after cardiopulmonary exercise test in obese women. Materials and Methods: a cross-?sectional study with 32 volunteer women, analyzed in the cardiopulmonary exercise test (CPX), allocated for convenience into obesity (GO, N=16) and non-?obese (GNO, N=16) group. We performed a clinical, anthropometric and adiposity and spirometry evaluation. The standard clinical CPX was assessed, (individualized ramp protocol), being done as ventilatory and metabolic measures (breath-?by-?breath), with a recording of interest variables at the rest (2?) and 5 initial (3' active recovery, 2'passive recovery). Oxygen kinetic after exercise was calculated by linear regression model of the decline slope of VO2 over time during the first minute of recovery (T?, VO2/t), and the HRR obtained by the difference between HR at the peak of the test and the HR at the first minute of recovery. Results: groups were homogeneous regarding age, height and spirometric measurements. Significant differences were found in the HRR (p=0,041) and VO2peak (p<0,001) between the groups. The oxygen kinetics presented a significant difference in the T? of VO2 (p=0,003) and VO2/t (p=0,041). It was observed that VO2peak (0,59), BMI (-?0,16) and HC (0,18) justified the variance of VO2/t in 72%. A negative colinearity between the HC and BMI adiposity measures was attested. Conclusion: young obese has delayed response of VO2 recovery kinetics and HRR regards no obese it suggests that obese has circulatory or reestablishment of energy reserves impairment on peripheral muscles and autonomic dysfunction, and it?s may contribute to the establishment of cardiovascular diseases, and increased morbidity and mortality rate in this population.
263

Express?o de GABA e plasticidade do fen?tipo neuroqu?mico e morfol?gico de c?lulas da Zona Subventricular p?s-natal

Sequerra, Eduardo Bouth January 2008 (has links)
Submitted by Helmut Patrocinio (hell.kenn@gmail.com) on 2017-11-09T01:14:16Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Eduardo_Sequerra_2008_TESE.pdf: 15865584 bytes, checksum: fcfa610e8add1f0dd217541746ae3a44 (MD5) / Approved for entry into archive by Ismael Pereira (ismael@neuro.ufrn.br) on 2017-11-09T11:57:09Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Eduardo_Sequerra_2008_TESE.pdf: 15865584 bytes, checksum: fcfa610e8add1f0dd217541746ae3a44 (MD5) / Made available in DSpace on 2017-11-09T11:57:29Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Eduardo_Sequerra_2008_TESE.pdf: 15865584 bytes, checksum: fcfa610e8add1f0dd217541746ae3a44 (MD5) Previous issue date: 2008 / A zona subventricular (SVZ) ? um s?tio de cont?nua neurog?nese em mam?feros p?s-natos e adultos. Ao longo de toda a vida, os progenitores neuronais gerados destinam-se ao bulbo olfat?rio (BO) para onde migram atrav?s da via migrat?ria rostral (RMS). Uma vez no BO, os novos neur?nios se diferenciam em neur?nios GABA?rgicos que integram-se ? circuitaria local. A express?o de GABA inicia ainda na zona germinativa. Essa express?o precoce poderia levar a hip?tese de que estes progenitores j? estariam comprometidos com o fen?tipo GABA?rgico. Por?m, para demonstrar seu comprometimento GABA?rgico, um dos passos necess?rios ? mostrar que a descarboxilase do ?cido glut?mico (GAD), a enzima que sintetiza GABA em neur?nios maduros, est? presente nestas c?lulas. Nesta tese mostramos que a express?o e atividade enzim?tica de GAD, s?o muito baixas na SVZ. Revelamos que o GABA presente em neur?nios imaturos da SVZ prov?m de uma via de s?ntese alternativa, a via da putrescina. Para analisar a import?ncia do GABA proveniente de putrescina para estas c?lulas realizamos a inibi??o farmacol?gica de sua s?ntese atrav?s da administra??o de DFMO. Observamos que o tratamento com DFMO regula positivamente a express?o de GAD na SVZ e RMS. Mostramos tamb?m que os neuroblastos da SVZ que expressam GABA s?o realmente pl?sticos quanto a sua escolha de fen?tipo neuroqu?mico. Quando explantes de SVZ s?o co-cultivados com fatias de telenc?falo embrion?rio dorsal, s?tio de gera??o de neur?nios glutamat?rgicos, uma subpopula??o se diferencia em neur?nios GABA?rgicos e outra menor em glutamat?rgicos. Sugerimos, portanto, que a via da putrescina permite que neur?nios imaturos sintetizem GABA sem, no entanto, haver comprometimento com o fen?tipo GABA?rgico. Esta produ??o de GABA parece ser importante para a migra??o de neuroblastos da SVZ, embora n?o tenhamos tido sucesso em mostrar um papel na prolifera??o com o decr?scimo na produ??o do precursor putrescina. Mostramos que a libera??o de GABA de putrescina parece ter um papel em inibir a express?o de GAD nestes neuroblastos. Em contrapartida, a subregula??o desta sinaliza??o levaria ao comprometimento pelo fen?tipo GABA?rgico. Se mudarmos os sinais apresentados ?s c?lulas da SVZ, como ?queles presentes na VZ do telenc?falo embrion?rio, pelo menos uma de suas subpopula??es ? capaz de mudar seu destino fenot?pico, e diferenciar-se em neur?nios glutamat?rgicos piramidais. / The subventricular zone (SVZ) is proliferative epithelium that continuously gives rise to new neurons in postnatal and adult mammals. The neurons generated in the SVZ migrate through the rostral migratory stream (RMS) where they differentiate in GABAergic interneurons. A characteristic of these neuron precursors is that they start to express GABA while they are still in the SVZ. This fact can lead to the conclusion that at this time they are already commited to the GABAergic phenotype. However, to affirm this one has to show that the origin of GABA in these cells is the same as in mature neurons. One of the most important steps to define GABAergic commitment in neurons is to demonstrate the expression of glutamic acid decarboxylase (GAD), the synthetic enzyme for GABA in mature neurons. Here we show that SVZ cells display low levels of GAD immunocytochemistry and enzyme activity as compared with the olfactory bulb. We also show that these cells are able to synthesize GABA using an alternative source, the putrescine pathway. To test the importance of putrescine made GABA in vivo, we pharmacolgically inhibited putrescine synthesis through DFMO administration. We observed that this treatment lead to an increase of GAD expression in the SVZ and RMS. We also show here that SVZ cells can display phenotypic plasticity. Co-culturing SVZ explants and dorsal telencephalic slices, a spot of glutamatergic neurogenesis, we observed that a subpopulation of SVZ derived neurons differentiated into GABAergic neurons and another into glutamatergic pyramidal neurons. Our working hypothesis is that the putrescine pathway is a mechanism to synthesize GABA without commitment to the GABAergic phenotype. The release of putrescine derived GABA inhibits GAD expression leaving these neuroblasts in an undifferentiated state. The inhibition of putrescine synthesis caused an upregulation of GAD expression which would lead to GABAergic commitment. If we present these neuroblasts with different signals, as those present in the embryonic dorsal telencephalon, they would show plasticity in their phenotypic fate and differentiate into other neurochemical and morphological phenotypes, one of which is the glutamatergic pyramidal neuron.
264

Síntese e caracterização do sistema nanoestruturado Sr1-XLaxTi1-yFeyO3: Aplicação como sensor de gás / Synthesis and characterization of nanostructured system Sr1-XLaxTi1-yFeyO3: application as gas sensor

Carlos Augusto Escanhoela Júnior 07 May 2015 (has links)
Os materiais de estrutura perovskita compreendem um vasto grupo de compostos cuja estrutura na sua forma mais simples pode ser representada pela f&oacute;rmula qu&iacute;mica ABO3. Uma das principais vantagens que a estrutura perovskita apresenta &eacute; o alto grau de flexibilidade em acomodar uma grande variedade de &aacute;tomos nos s&iacute;tios A e B, permitindo um maior controle de suas propriedades f&iacute;sicas e qu&iacute;micas bem como a manuten&ccedil;&atilde;o de sua estrutura b&aacute;sica, mesmo para altas concentra&ccedil;&otilde;es de &aacute;tomos substituintes. Devido estas propriedades, estes materiais t&ecirc;m sido aplicados com sucesso como capacitores, varistores, fotoeletrodos, mem&oacute;riasferroel&eacute;tricas e sensores de gases. Nas &uacute;ltimas d&eacute;cadas, tem sido reportada a utiliza&ccedil;&atilde;o do titanato de estr&ocirc;ncio (SrTiO3, ST) na forma de filmes finos e espessos como sensor de g&aacute;s oxig&ecirc;nio em altas temperaturas (&gt;500 &deg;C). Recentemente, foi mostrado que o titanato de estr&ocirc;ncio dopado com Fe apresentava uma excelente sensibilidade ao g&aacute;s oz&ocirc;nio. Entretanto, neste trabalho, somente uma composi&ccedil;&atilde;o foi caracterizada e nem todas as propriedades importantes em rela&ccedil;&atilde;o a esta aplica&ccedil;&atilde;o foram completamente exploradas. Neste contexto, esta tese de doutorado teve como objetivo verificar o efeito da substitui&ccedil;&atilde;o do &aacute;tomo de estr&ocirc;ncio pelo lant&acirc;nio e do tit&acirc;nio pelo Ferro no composto SrTiO3 na forma de p&oacute; e filmes finos nanoestruturados com a finalidade de verificar o efeito destas substitui&ccedil;&otilde;es nas propriedades sensoras do material. Inicialmente, com o objetivo de avaliar a influ&ecirc;ncia da adi&ccedil;&atilde;o de La na estrutura do composto ST, amostras na forma de p&oacute; do sistema Sr1-xLaxTiO3.(SLT) foram preparadas atrav&eacute;s do m&eacute;todo dos precursores polim&eacute;ricos. Posteriormente, pelo mesmo m&eacute;todo, foram sintetizadas amostras do sistema SrTi1-xFexO3 (STF) e Sr1-XLaxTi1-yFeyO3 (SLTF). A partir das amostras na forma de p&oacute; e na forma de solu&ccedil;&atilde;o, filmes finos e espessos foram respectivamente obtidos atrav&eacute;s das t&eacute;cnicas de deposi&ccedil;&atilde;o por feixe de el&eacute;trons (EBD) e spin-coating (SC). As amostras nanoestruturadas na forma de p&oacute; e na forma de filmes foram caracterizadas por difra&ccedil;&atilde;o de raios X, espectroscopia de absor&ccedil;&atilde;o de raios X (XANES) na borda K do Ti e do Fe e espectroscopia de fotoel&eacute;trons excitados por raios X (XPS). A an&aacute;lise morfol&oacute;gica foi realizada atrav&eacute;s das t&eacute;cnicas de microscopia eletr&ocirc;nica de varredura (MEV) e microscopia de for&ccedil;a at&ocirc;mica (MFA). As amostras do sistema STF e SLTF na forma de filmes finos foram avaliadas em rela&ccedil;&atilde;o &agrave; sensibilidade aos gases O3, NO2, NH3 e CO. Os resultados indicaram que os filmes do sistema SLTF depositados pela t&eacute;cnica de deposi&ccedil;&atilde;o por feixe de el&eacute;trons apresentam uma maior sensibilidade ao g&aacute;s oz&ocirc;nio, enquanto o filme de mesma composi&ccedil;&atilde;o depositado pelo m&eacute;todo de spin-coating apresentou uma melhor estabilidade e tempo de recupera&ccedil;&atilde;o em rela&ccedil;&atilde;o a este mesmo g&aacute;s. / The perovskite structure materials comprise a large group of compounds with the structure in simple form can be represented by the ABO3. chemical formula. The main advantage that the perovskite structure presents is the high degree of flexibility to accommodate a wide variety of atoms in sites A and B, allowing a greater control of physical and chemical properties of the material, maintaining its structure even for a high concentrations of substituent\'s. Due to these properties, these materials have been successfully applied as capacitors, varistors, photoelectrodes, ferroelectric memories and gas sensors. In the last decade, strontium titanate (SrTiO3, ST) in the form of thin and thick films have been reported as oxygen gas sensor at higher temperatures (&gt; 500 &deg;C). Recently, strontium titanate doped with Fe was used as the first ozone sensor. However, the work was carried out only with a certain composition and some important properties for this application have not been fully exploited. In this context, this PhD thesis aimed to the synthesis of strontium titanate system in powder form and nanostructured thin films with the substitution of Sr for La and Ti for Fe. In order to verify the effect of these substitutions in material properties initially Sr1-xLaxTiO3 (SLT) samples were prepared in powder form by the polymeric precursor method in order to evaluate the influence of the addition of La in the structure of the compound ST. Subsequently, samples were synthesized from SrTi1-x Fex O3 (STF) and Sr1-XLaxTi1-yFeyO3 (SLTF) systems through the polymeric precursors, which were used for the deposition of thin and thick films, which were respectively obtained through electron beam deposition techniques (EBD) and spin-coating (SC). Samples in the form of nanostructured powder and thin films were characterized by X-ray diffraction, X-ray absorption spectroscopy (XANES) at Ti and Fe K-edges and by X-ray photoelectron spectroscopy (XPS). Morphological analysis was performed using the scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The STF and SLTF samples in a thin film form were evaluated towards their sensitivity to O3, NO2, NH3 and CO gases. The results indicated that SLTF films deposited by electron beam deposition technique exhibit higher sensitivity to ozone gas. However the same composition deposited by spin-coating showed a better stability and recovery time relative to the same gas.
265

Estudo da comunidade de bact?rias diazotr?ficas do g?nero Burkholderia em associa??o com cana-de-a??car e descri??o de Burkholderia silvatlantica / Community study of the of Burkholderia diazotrophic bacteria in association with sugarcane and description of Burkholderia silvatlantica

Perin, Liamara 15 February 2007 (has links)
Made available in DSpace on 2016-04-26T19:39:29Z (GMT). No. of bitstreams: 1 2007- Liamara Perin.pdf: 5126010 bytes, checksum: 0973e83f604e8d397ec95ef00c19da99 (MD5) Previous issue date: 2007-02-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The sugarcane crop in Brazil occupies almost six million hectares and it is economically important for the generation of jobs and energy production. Among the Poaceas species, it is the crop that receives more contributions from the biological nitrogen fixation, however until this moment it is unknown what organisms are responsible for the best results observed. Innumerable genuses of diazotrophic bacteria were found in association with sugarcane, among them the genus Burkholderia. However little is known about this genus in association with sugarcane. The objective of this study was to isolate and to characterize diazotrophic Burkholderia bacteria in association with sugarcane, and to describe a new species of diazotrophic Burkholderia bacteria. For that, samples of plants were collected in four crop areas, in different Brazilian states, for counting and isolating the bacteria community using the culture medias LGI and JMV. The isolates were characterized physiological, morphologically and molecularly. Sixty-four Burkholderia diazotrophic isolates were gotten that presented versatile metabolism, and the majority differing from the analyzed species patterns. Only five isolates were identified by the ARDRA technique, two belonging to B. tropica species and three to B. unamae. A big group, with 32 isolates, presented the same restriction profile by the ARDRA technique and differed from the analyzed species. The sequencing of the 16S rDNA region of two of these isolates showed that they don t belong to the already described species. This group, from sugarcane plants together with similar maize and pineapple isolates, was described as a new species named B. silvatlantica. The characterization of this new Burkholderia specie was confirmed by the hybridization DNA: DNA technique, presenting only 30% of similarity with the closest species, and the sequencing of the 16S rDNA region. B. Silvatlantica fixed nitrogen in microaerophilic conditions, and it had no capacity of inorganic phosphate solubilization, it did not produce vegetal hormones and had no nodulation capacity in leguminous. These results confirmed that Burkholderia is a rich genus in diazotrophics species and colonize different habitats. / A cultura da cana-de-a??car no Brasil ocupa mais de seis milh?es de hectares sendo importante economicamente pela gera??o de empregos e bastante promissora para a produ??o de energia. Dentre as Poaceas (gram?neas), ? a cultura que mais recebe contribui??es da fixa??o biol?gica de nitrog?nio, por?m ainda n?o se sabe ou n?o se conhece qual ou quais organismos s?o respons?veis pelos melhores resultados observados. In?meros g?neros de bact?rias diazotr?ficas foram encontrados em associa??o com cana-de-a??car, dentre eles o g?nero Burkholderia, at? o momento pouco estudado em associa??o com esta cultura. O objetivo deste estudo foi isolar e caracterizar bact?rias diazotr?ficas do g?nero Burkholderia em associa??o com cana-de-a??car e descrever uma nova esp?cie de bact?ria diazotr?fica do g?nero Burkholderia. Para tal, foram coletadas amostras de plantas em canaviais de quatro estados brasileiros para contagem e isolamento da comunidade de bact?rias utilizando os meios de cultura LGI e JMV. Os isolados foram caracterizados fisiologicamente, morfologicamente e molecularmente. Foram obtidos 64 isolados diazotr?ficos do g?nero Burkholderia, que apresentaram metabolismo vers?til e diferiram dos padr?es das esp?cies analisadas. Apenas cinco isolados foram identificados pela t?cnica de ARDRA, dois pertenceram a esp?cie B. tropica e tr?s a B. unamae. Um grande grupo, com 32 isolados, apresentou mesmo perfil de restri??o pela t?cnica de ARDRA e diferiu das esp?cies analisadas. O sequ?nciamento da regi?o 16S rDNA de dois destes isolados mostrou que eles n?o pertencem ?s esp?cies j? descritas. Este grupo obtido de plantas de cana-de-a??car, juntamente com isolados similares, obtidos de milho e abacaxi, foi descrito como uma nova esp?cie de nome B. silvatlantica. A nova esp?cie de Burkholderia foi confirmada pelos experimentos de hibridiza??o DNA:DNA, com apenas 30% de similaridade com a esp?cie mais pr?xima. B. silvatlantica fixou nitrog?nio em condi??es microaerof?licas, n?o apresentou capacidade de solubiliza??o de fosfato inorg?nico, n?o produziu horm?nios vegetais e n?o apresentou capacidade de nodula??o em leguminosas. Estes resultados confirmaram que o g?nero Burkholderia ? rico em esp?cies diazotr?ficas e est?o presentes em diferentes habitats.
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Leguminosas forrageiras tropicais cultivadas sob n?veis de sombreamento. / Tropical forage legumes grown under increasing shade levels.

Rocha, Norberto Silva 04 September 2008 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-12T11:26:17Z No. of bitstreams: 1 2008 - Norberto Silva Rocha.pdf: 1212597 bytes, checksum: 348564fc2134bb9135658be25a94d180 (MD5) / Made available in DSpace on 2017-06-12T11:26:17Z (GMT). No. of bitstreams: 1 2008 - Norberto Silva Rocha.pdf: 1212597 bytes, checksum: 348564fc2134bb9135658be25a94d180 (MD5) Previous issue date: 2008-09-04 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ - FAPERJ / This research was carried on at Universidade Federal Rural do Rio de Janeiro, at DNAP/IZ, Forage and Pasture Department, Serop?dica, Rio de Janeiro State, Brazil. Four tropical forage legumes cultivation were assessed: (Calopogonium mucunoides (calopo), Pueraria phaseoloides (puero), Macrotyloma axillare (archer) and Neonotonia wightii (perennial soybean)) submitted under artificial increasing shade levels (0, 30, 50 and 70% shade) during rainy and dry seasons. Randomized blocks experimental design with four replications and 4x4 factorial arrangement was performed. The qualitative variable (species) by SNK test at 5% probability as well as the quantitative one (shade) by regression statistic analysis were evaluated. The estimated parameters were: dry matter production (DMP), crude protein level (CP), crude protein production (CPP), neutral detergent fiber (NDF), cellulose (CEL), hemicellulose (HEM) and lignin (LIG), leaf/steam ratio (RL/S) and also mineral composition (calcium (Ca), phosphorus (P) and potassium (K)). Puero and the archer presented the biggest PMS during rainy and dry season, respectively. Gains on legumes DMP according to increasing shade levels during both evaluation periods were observed. Exclusively during rainy season, highest DMP under 30% shade level was presented by calopo. The puero and the archer presented bigger PMS while submitted to 50% shading treatment, during both evaluation periods. At 70% in rainy season as at 50% in dry one, highest DMP by perennial soybean was demonstrated. The biggest CP contents were observed by puero species and perennial soybean in both evaluation periods. For the CP content, only during dry season an increment has been seen according to the shading levels. The biggest CPP has been observed with the puero on the rainy season and with the archer on the dry one. The smallest and biggest NDF and CEL contents were observed with the species calopo and puero, respectively, during rainy seasons. On this evaluation the HEM and LIG contents did not varied (P>0.05) among legumes. During dryness, perennial soybean presented lowers NDF, CEL and HEM contents, while the biggest contents were observed on puero. For the shading levels purpose, it has been observed an increase on the NDF, CEL and HEM contents with the shading improvement on both evaluation seasons. No effect on LIG were observed on species or shading levels, during both seasons. Calopo and perennial soybean presented bigger RL/S on the rainy season and during the dry one bigger RL/S was shown with the perennial soybean. Regarding shading effects over RL/S values, a reduction related to studied treatments have been observed. For the mineral composition there was no difference on the Ca and P contents for the legumes focused on this study, however a lower K content was got by archer during rainy season. On dry season, the Archer obtained bigger P content and lower Ca and K ones. No difference on P and K contents for puero and perennial soybean legumes. A bigger Ca content was obtained by perennial soybean during that time. The increasing shading levels leads to increments on Ca, P and K contents, during both evaluated periods. Under an intensified shading level the biggest increase was observed on the studied minerals. Nevertheless, the best result for the tropical forage legumes cultivation, submitted to different shading levels, was presented on the 50% shade level, where the biggest DMP concentration, intermediate gains in fiber composition and increment to the forage have occurred under this condition. / O experimento foi conduzido na Universidade Federal Rural do Rio de Janeiro, no Setor de Forragicultura e Pastagem do DNAP/IZ, Serop?dica, RJ. Foi estudado o cultivo de quatro leguminosas forrageiras tropicais (Calopogonium mucunoides (calopog?nio), Pueraria phaseoloides (kudzu tropical), Macrotyloma axillare (macrotiloma) e Neonotonia wightii (soja perene)) submetidas a n?veis de sombreamento artificiais (0, 30, 50 e 70% de sombra), durante os per?odos das ?guas e seca. O delineamento experimental foi em blocos ao acaso com esquema fatorial 4x4, com quatro repeti??es. A vari?vel qualitativa (esp?cie) foi estudada utilizando-se o teste SNK a 5% de probabilidade, e a vari?vel de car?ter quantitativo (sombreamento) foi avaliada por meio de an?lise de regress?o. Os par?metros avaliados foram: produ??o de mat?ria seca (PMS), teor de prote?na bruta (PB), produ??o de prote?na bruta (PPB), a composi??o da fra??o fibrosa (fibra em detergente neutro (FDN), fibra em detergente ?cido (FDA), celulose (CEL), hemicelulose (HEM), lignina (LIG)), a rela??o folha/haste (RF/H) e a composi??o mineral: c?lcio (Ca), f?sforo (P) e pot?ssio (K). O kudzu tropical e o macrotiloma apresentaram as maiores PMS durante os per?odos das ?guas e seca, respectivamente. Foram observados incrementos na PMS das leguminosas estudadas em fun??o dos n?veis de sombreamento, durante os dois per?odos de avalia??o. O calopog?nio apresentou maior PMS sob o n?vel de 30% de sombra, sendo somente avaliado no per?odo das ?guas. O kudzu tropical e o macrotiloma apresentaram maior PMS quando submetidas ao tratamento de 50% de sombreamento, durante os dois per?odos de avalia??o. A soja perene apresentou maior PMS sob o n?vel de 70% na ?poca das ?guas e no tratamento de 50% no per?odo seco. Os maiores teores de PB foram obtidos pelas esp?cies kudzu tropical e soja perene nos dois per?odos de avalia??o. Para o teor de PB, somente durante o per?odo seco foi observado incremento em fun??o dos n?veis de sombreamento. A maior PPB foi observada para o kudzu tropical na ?poca das ?guas e para o macrotiloma na ?poca seca do ano. Os menores e os maiores teores de FDN e CEL foram observados nas esp?cies calopog?nio e kudzu tropical, respectivamente, durante a esta??o das ?guas. Nesta avalia??o os teores de HEM e LIG n?o diferiram (P>0,05) entre as leguminosas. No per?odo seco, a soja perene apresentou os menores teores de FDN, CEL e HEM, sendo observado os maiores teores no kudzu tropical. Para o efeito dos n?veis de sombreamento, foi observado aumento no teor de FDN, CEL e HEM ? medida que o sombreamento foi intensificado, nos dois per?odos de avalia??o. N?o foram observados efeitos da esp?cie e dos n?veis de sombreamento para o teor de LIG, durante as duas esta??es do ano. O calopog?nio e a soja perene apresentaram maior RF/H na ?poca das ?guas e, durante a seca foi observado maior RF/H na soja perene. Quanto ao efeito dos n?veis de sombreamento sobre a RF/H foi observada redu??o nesses valores em fun??o dos tratamentos estudados, durante os dois per?odos de avalia??o. Quanto a composi??o mineral n?o houve diferen?a entre os teores de Ca e P para as leguminosas estudadas, entretanto o menor teor de K foi obtido pelo macrotiloma, durante o per?odo das ?guas. Na ?poca seca, o macrotiloma obteve maior teor de P e menores teores de Ca e K. N?o houve diferen?a entre os teores de P e K para as leguminosas kudzu tropical e soja perene. O maior teor de Ca foi obtido pela soja perene neste per?odo. Os n?veis crescentes de sombreamento acarretaram incremento nos teores de Ca, P e K, durante os dois per?odos avaliados. Sob o n?vel de sombreamento mais intenso foi observado o maior incremento dos minerais estudados. Contudo, a melhor resposta obtida para o cultivo de leguminosas forrageiras tropicais, submetidas a diferentes intensidades de sombreamento, foi apresentada sob o n?vel de 50% de sombra, onde concentraram maior PMS, acr?scimos intermedi?rios na composi??o fibrosa e incremento de minerais ?s forrageiras quando produzidas nessa condi??o.
267

Efici?ncia da inocula??o de Herbaspirillum seropedicae estirpe ZAE94 em dois gen?tipos de milho (Zea mays) / Efficiency of inoculation of Herbaspirillum seropedicae ZAE94 strain in two genotypes of maize (Zea mays)

BREDA, Farley Alexandre da Fonseca 24 February 2014 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-20T19:46:54Z No. of bitstreams: 1 2014 - Farley Alexandre da Fonseca Breda.pdf: 375196 bytes, checksum: 7001327c707e778b8396891ebff2285d (MD5) / Made available in DSpace on 2017-06-20T19:46:54Z (GMT). No. of bitstreams: 1 2014 - Farley Alexandre da Fonseca Breda.pdf: 375196 bytes, checksum: 7001327c707e778b8396891ebff2285d (MD5) Previous issue date: 2014-02-24 / CAPES / Currently with the constant demand for increased productivity and successive increasing in the prices of fertilizers, especially nitrogen, new technologies are being studied. One that has been highlighted due to low cost of deployment and promising results is the biological nitrogen fixation in grasses. The aim of this work was to study the effect of inoculation of diazotrophic bacteria Herbaspirillum seropedicae strain ZAE94 in two maize genotypes selected for the climatic conditions and low fertility soils, and the ability to reduce the use of nitrogen fertilizers, as well as increasing crop productivity. To this end, two experiments were implanted, one during the off-season and another in the harvesting of agricultural year 2012/2013. In both experiments the maize hybrids (BRS 1030 and BRS 1060) were inoculated with the ZAE94 strain, following the experimental design of a randomized block design with a factorial 2 x 2 x 3, comprising the inoculation, genotype and fertilization respectively, with six replicates. The variables analyzed were the average yield, weight of 1000 grains, content and accumulation of nitrogen in the grain and nitrogen use efficiency of fertilizer. The results were tested for normality and homogeneity, were subjected to analysis of variance, and when significant treatments, these were subjected to medium testing, using test t at 10%. For all variables the hybrid BRS 1030 was greater than the BRS 1060. For the inoculation factor and in the off-season, it was observed a triple interaction for weight of 1,000 grains; and when the inoculation is associated with the highest nitrogen rate it promoted an increase in the productivity of the hybrid BRS 1060. In harvesting period, regardless of genotype and fertilizer used, it was observed that inoculating the seed of hybrids was always better than without inoculation. For efficiency of nitrogen fertilizer usage it was observed that, in general, the BRS 1030 was more efficient than the BRS 1060. / Atualmente com a constante demanda pelo aumento de produtividade e os sucessivos aumentos nos pre?os dos fertilizantes, principalmente os nitrogenados, novas tecnologias vem sendo estudadas. Uma que vem se destacando devido ao seu baixo custo de implanta??o e os seus promissores resultados ? a fixa??o biol?gica de nitrog?nio em gram?neas. O objetivo dessa disserta??o foi estudar o efeito da inocula??o da bact?ria diazotr?fica Herbaspirillum seropedicae estirpe ZAE94, em dois gen?tipos de milho selecionados devido sua adapta??o a condi??es clim?ticas e solos de baixa fertilidade, e quanto ? capacidade de reduzir o uso de fertilizantes nitrogenados, bem como, incrementar a produtividade da cultura. Para tal, foram implantados dois experimentos um no per?odo da safrinha e outro na safra do ano agr?cola 2012/2013. Em ambos os experimentos os h?bridos de milho (BRS 1030 e BRS 1060) foram inoculados com a estirpe ZAE94, seguindo o delineamento experimental em blocos ao acaso com o fatorial de 2 x 2 x 3, sendo os fatores inocula??o, gen?tipo e aduba??o respectivamente, com 6 repeti??es. As vari?veis analisadas foram produtividade m?dia, peso de 1.000 gr?os, teor e ac?mulo de nitrog?nio nos gr?os e efici?ncia do uso do nitrog?nio fertilizante. Os resultados foram testados quanto a normalidade e homogeneidade, logo ap?s submetidos ? analise de vari?ncia e quando significativo, os mesmos foram submetidos ao teste de media. O teste de m?dia utilizado foi o teste t, a 10%. Para todas as vari?veis analisadas o h?brido BRS 1030, foi superior a BRS 1060. Para o fator inocula??o, no per?odo da safrinha, foi observada uma intera??o tripla para o peso de 1.000 gr?os, onde quando a inocula??o foi associada a maior dose de nitrog?nio ela promoveu um aumento na produtividade do h?brido BRS 1060. No per?odo da safra, independente do gen?tipo e da aduba??o utilizada observou-se que inocular a semente dos h?bridos e sempre melhor do que n?o realizar a inocula??o. Para efici?ncia do uso do nitrog?nio fertilizante foi observado que, de forma geral, o BRS 1030 foi mais eficiente do que o BRS 1060.
268

Atividade das enzimas nitrogenase e nitrato redutase em plantas de feijoeiro oriundas de sementes com diferentes teores de molibd?nio. / Activities of nitrogenase and nitrate reductase enzymes in common bean plants originating from seeds with different molybdenum concentrations.

Almeida, Fernanda Fatima Delgado de 11 February 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-07-07T13:07:27Z No. of bitstreams: 1 2010 - Fernanda Delgado Almeida.pdf: 626850 bytes, checksum: 3a7edfb868e6c7a04004c0ce79c36a91 (MD5) / Made available in DSpace on 2017-07-07T13:07:27Z (GMT). No. of bitstreams: 1 2010 - Fernanda Delgado Almeida.pdf: 626850 bytes, checksum: 3a7edfb868e6c7a04004c0ce79c36a91 (MD5) Previous issue date: 2010-02-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Seeds with high molybdenum (Mo) concentration can provide amounts of the nutrient highly enough to guarantee an adequate plant growth. An essay and two experiments were carried out in pots to evaluate the effect of Mo concentration in seeds of common bean (Phaseolus vulgaris L.) on the assimilation of N from the soil and the biological N2 fixation (BNF), through measuring the activities of the nitrogenase and nitrate reductase enzymes and the contribution of the BNF by the 15N isotope dilution, at different plant growth stages. The substrate was A horizon of Argisol (Hapludult) in 10 kg pots. Seeds of the cultivar Carioca enriched or not with Mo were tested. The essay had a 2x3 factorial design: two seed Mo concentrations (low and high) and three N sources (without N, inoculated and mineral N), with two replicates. Plants were harvested at 42 days after emergence (DAE). High concentration of Mo in seeds increased shoot dry mass, the nitrate reductase activity and shoot N accumulation, but reduced nodule number. The experiment 1 had a 2x2x4 factorial design: two seed Mo concentrations (low and high), two N sources (inoculated and mineral N) and four dates of harvest (20, 34, 45 and 55 DAE), with five replicates. An extra treatment was included, with seeds with high Mo concentration, inoculation and Mo added to the soil, with four harvests. No effect of Mo added to the soil was identified, as compared to the high seed Mo. High seed Mo increased the leaf area and shoot dry mass at the four times of harvest, and the pod mass at 55 DAE, at both N sources. Seeds with high Mo concentration increased the nitrate reductase activity at 45 DAE under mineral N, and nitrogenase activity at 20 and 45 DAE under inoculation. High Mo seeds increased shoot N accumulation at both N sources at pod filling stage. The experiment 2 had a 2x2x2 factorial design: two seed Mo concentrations (low and high), two N sources (inoculated and mineral N) and two dates of harvest (38 and 51 DAE), with five replicates. The soil was previously fertilized with 15N-enriched urea. Non-nodulating bean, sunflower and sorghum were used as control plants. At 51 DAE, plants originating from high Mo seeds had higher shoot mass at both N sources, but lower nodule number under mineral N. High Mo seed increased nitrate reductase activity at 51 DAE at both N sources, and nitrogenase activity at 38 DAE in inoculated plants. High Mo seeds increased shoot N accumulation at both N sources. High Mo seeds improved the contribution of the BNF at the pod filling stage, as estimated by the 15N isotope dilution technique. It is concluded that common bean seeds enriched with Mo stimulate the assimilation of N from the soil and the BNF, increasing the accumulation of biomass / Sementes com elevadas concentra??es de molibd?nio (Mo) podem fornecer quantidades do nutriente suficientes para garantir adequado crescimento ?s plantas. Foram conduzidos um ensaio e dois experimentos com objetivo de avaliar o efeito do teor de Mo em sementes de feijoeiro (Phaseolus vulgaris L.) na assimila??o do N do solo e na fixa??o biol?gica do N2 (FBN), atrav?s da mensura??o das atividades das enzimas nitrogenase e nitrato redutase, e da contribui??o da FBN pela dilui??o isot?pica de 15N, em diferentes est?dios de desenvolvimento vegetal. O substrato foi horizonte A de Argissolo em vasos de 10 kg, utilizando-se sementes da cultivar Carioca enriquecidas ou n?o com Mo. O ensaio teve arranjo fatorial 2x3: dois teores de Mo na semente (baixo e alto) e tr?s fontes de N (sem N, inoculado e N mineral), com duas repeti??es e coleta aos 42 dias ap?s emerg?ncia (DAE). O alto Mo da semente aumentou a atividade da nitrato redutase, a massa e a acumula??o de N na parte a?rea, mas reduziu o n?mero de n?dulos. O experimento 1 teve arranjo fatorial 2x2x4: dois teores de Mo na semente (baixo e alto), duas fontes de N (inoculado e N mineral) e quatro ?pocas de coleta (20, 34, 45 e 55 DAE), com cinco repeti??es. Foi inclu?do um tratamento extra, com sementes com alto Mo, inocula??o e adi??o de Mo ao solo. N?o foi identificado efeito do Mo adicionado ao solo quando comparado com o alto Mo na semente. O alto Mo na semente aumentou a ?rea foliar e a massa de parte a?rea nas quatro ?pocas de coleta, e a massa de vagem aos 55 DAE, nas duas fontes de N. Sementes com alto Mo aumentaram a atividade da nitrato redutase aos 45 DAE sob N mineral, e a atividade da nitrogenase aos 20 e 45 DAE sob inocula??o. Sementes com alto Mo aumentaram a acumula??o de N na parte a?rea nas duas fontes de N no est?dio de enchimento das vagens. O experimento 2 teve arranjo fatorial 2x2x2: dois teores de Mo na semente (alto e baixo), duas fontes de N (inoculado e N mineral) e duas coletas (38 e 51 DAE), com cinco repeti??es. O solo foi previamente adubado com ur?ia enriquecida com 15N. O feij?o n?o nodulante, girassol e sorgo serviram como plantas controle. Aos 51 DAE, plantas oriundas de sementes com alto Mo tiveram maior massa de parte a?rea nas duas fontes de N, mas menor n?mero de n?dulos sob N mineral. O alto Mo nas sementes aumentou a atividade da nitrato redutase aos 51 DAE, nas duas fontes de N, e a atividade da nitrogenase aos 38 DAE nas plantas inoculadas. Sementes com alto Mo aumentaram a acumula??o de N na parte a?rea nas duas fontes de N. Sementes com alto Mo aumentaram a contribui??o da FBN no est?dio de forma??o das vagens. Conclui-se que sementes de feijoeiro enriquecidas com Mo estimulam tanto a assimila??o do N do solo quanto a FBN, aumentando a acumula??o de biomassa e de N do feijoeiro.
269

Silenciamento g?nico por miRNA do transportador OsAMT1.3 e seu efeito sobre a efici?ncia de absor??o de am?nio (Oryza sativa L.) / Transporter OsAMT1.3 gene silencing by miRNA and its effects in the ammonium efficiency uptake (Oryza sativa L.)

JACQUES, Marcela de Lemos Neves 30 May 2014 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-07-26T18:47:21Z No. of bitstreams: 1 2014 - Marcela Jacques de Lemos Neves.pdf: 434472 bytes, checksum: c9817e97c5d136299acb936ad4b87b6f (MD5) / Made available in DSpace on 2017-07-26T18:47:21Z (GMT). No. of bitstreams: 1 2014 - Marcela Jacques de Lemos Neves.pdf: 434472 bytes, checksum: c9817e97c5d136299acb936ad4b87b6f (MD5) Previous issue date: 2014-05-30 / FAPERJ / The main goal of this study was evaluate the effect of downregulation of the ammonium transporter OsAMT1.3 in the ammonium uptake through the high affinity system, as well as the effects on nitrogen metabolism. To perform the OsAMT1.3 gene silencing, it was used the artificial micro RNA (amiRNA) technology. In this system, the OsAMT1.3 coding region sequence (cds) is inserted in W marcelaMD3 website and putatives amiRNAs to silencing OsAMT1.3 were made. The amiRNA was inserted by PCR using the pNW55 vector as template. The amiRNA was inserted in the IRS154 vector using the T4 DNA ligase. The IRS154 plus amiRNA was cloned in the E. coli by electroporation. After rice transformation of Nipponbare variety through Agrobacterium and Hygromycin selection, 14 lineages were obtained. Six lineages showed high seed production and only one lineage with abnormal growth. After seed production in a greenhouse, the lineages L1, L2 and L6 were selected to further experiments evaluating the effects of OsAMT1.3 downregulation. First, the lineages selected were evaluated about the levels of OsAMT1.3 downregulation. The rice lineages transformed with amiRNA showed lower level of OsAMT1.3 expression compared to control plants, however, different levels of OsAMT1.3 downregulation was observed. The lineage L1 showed lower levels of OsAMT1.3 downregulation, L2 and L6 showed higher levels of OsAMT1.3 downregulation. The lineages L1, L2 and L6 as well as IRS control plant (transformed with empty vector) were grown in growth chamber at 30 days after germination, and the treatments used were: N starvation for three days, resupply with 0.15 mM of NH4+-N (low level) and 2.0 mM of NH4+-N (high level). The lineages L1, L2 and L6 showed lower NH4+ uptake with 0.15 mM of NH4+-N compared to control plants (IRS), on the other hand, the plants grown with 2.0 mM of of NH4+-N did not show NH4+ uptake differences, except L1. The expression of OsAMT1.1, OsAMT1.2 and OsAMT1.3 ammonium transporters were upregulated with 0.15 mM of NH4+-N in the control plants (IRS); in the lineages L1, L2 and L6 showed downregulation of the OsAMT1.1, OsAMT1.2 and OsAMT1.3 genes. The lower NH4+ uptake with 0.15 mM of NH4+-N resulted in lower levels of NH4+-N and Amino-N in the roots in the lineages, while the NH4+-N and Amino-N in the plants grown with 2.0 mM of NH4+-N was minimally changed. The results indicate that OsAMT1.3 downregulation leads to OsAMT1.1 and OsAMT1.2 downregulation as well, decreasing the NH4+ uptake. Despite the OsAMT1.3 lower expression compared to OsAMT1.1 and OsAMT1.2, the OsAMT1.3 transporter may be involved in the nitrogen uptake efficiency in low levels of NH4+. / O objetivo deste trabalho foi estudar o efeito do silenciamento do gene do transportador OsAMT1.3 em arroz sobre a habilidade das plantas em absorver o N-NH4+ atrav?s do sistema de alta afinidade, bem como os reflexos sobre o metabolismo de nitrog?nio. Para o silenciamento do gene OsAMT1.3 foi usada a tecnologia do miRNA artificial (amiRNA). Para tanto, a sequ?ncia codante do gene (cds) OsAMT1.3 ? inserida no sistema WMD3 que indica sequ?ncias de amiRNA?s para silenciar o pr?prio OsAMT1.3. A inser??o do amiRNA foi feita por PCR usando o vetor pNW55 como molde. O miRNA foi inserido no vetor IRS154 por corte e liga??o usando a enzima T4 DNA ligase. O produto da liga??o foi introduzido em E. coli por eletropora??o. Ap?s a transforma??o de arroz da variedade Nipponbare mediada por Agrobacterium. A sele??o das plantas transformadas foi feita com o antibi?tico Higromicina. No total foram obtidas 14 linhagens transformadas. Para confirmar que as plantas mutantes possuiam a constru??o, foi realizado o teste com a folha bandeira em solu??o de higromicina. Seis linhagens apresentaram boa produ??o de sementes e houve uma linhagem com crescimento anormal. Ap?s a multiplica??o das linhagens em casa de vegeta??o, foram selecionadas as linhagens L1, L2 e L6 para os experimentos de an?lise dos efeitos do silenciamento do gene OsAMT1.3. Primeiramente, as linhagens selecionadas foram avaliadas quanto ao n?vel de silenciamento do gene OsAMT1.3. As linhagens de arroz transformadas apresentaram maior n?vel de silenciamento do gene OsAMT1.3 quando comparadas ?s plantas controle, no entanto, diferentes n?veis de silenciamento foram observados. A linhagem L1 apresentou menor n?vel de silenciamento do gene OsAMT1.3, enquanto L2 e L6 apresentaram maior silenciamento. As linhagens L1, L2 e L6 e a planta controle IRS (transformada com o vetor vazio) foram cultivadas em c?mara de crescimento at? os 30 dias ap?s a germina??o, com a aplica??o dos seguintes tratamentos: sem N por tr?s dias, ressuprimento com 0,15 mM de N-NH4+ ap?s tr?s dias de priva??o de N (baixa dose) e 2,0 mM de N-NH4+ constante (alta dose). As linhagens L1, L2 e L6 apresentaram menor absor??o de NH4+ com 0,15 mM de N-NH4+ quando comparadas com as plantas controle (IRS), enquanto as plantas cultivadas com 2,0 mM de N-NH4+ n?o apresentaram diferen?as na absor??o de NH4+. A express?o dos genes dos transportadores de NH4+ OsAMT1.1, OsAMT1.2 e OsAMT1.3 foi induzido pelo tratamento com 0,15 mM de N-NH4+ nas plantas controle (IRS), enquanto as linhagens transformadas apresentaram repress?o dos genes OsAMT1.1, OsAMT1.2 e OsAMT1.3. A menor absor??o de NH4+ com 0,15 mM de N-NH4+ causou menor n?vel de N-NH4+ e N-amino nas ra?zes das linhagens transformadas, enquanto nas plantas com 2,0 mM de N-NH4+ houve pouca altera??o nos conte?dos de N-NH4+ e N-amino. Os resultados indicam que o silenciamento do gene OsAMT1.3 provoca regula??o negativa dos transportadores OsAMT1.1 e OsAMT1.2, alterando a absor??o de NH4+. Apesar do gene OsAMT1.3 ser menos expresso que os genes OsAMT1.1 e OsAMT1.2, o transportador OsAMT1.3 pode estar envolvido na efici?ncia de absor??o em baixas doses de NH4+.
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Jonsson, Åsa, Maathz, Carl-Philip January 2005 (has links)
Vår kandidatarbetstid har resulterat i nio stycken småfilmer som är till för att ge mer information om BTH och regionen för nyfikna. Fyra av dessa filmer innerhåller lite mer information om region, boende/kommunikationer, skolan och det studiesociala. Syftet med dessa fyra filmer är att blanda in BTH på olika sätt, att man sätter skolan som en röd tråd även i region och bostadsfrågorna. Vi gjorde även fyra stycken studentintervjuer, för att visa vad nuvarande studenter tycker om bostadsmöjligheterna och det studiesociala mm. Vi ville även visa att det finns folk från Kiruna i norr till Lund i Söder, som går på skolan, och att det finns många olika typer av människor som du får möjlighet att lära känna om du börjar studera här. Det blir variation och man tar till sig det som sägs på ett annat sätt, än i de mer traditionella informationsfilmerna. Sist men inte minst så gjorde vi en mässfilm som innehåller bilder och ord från de fyra informationsfilmerna, och som ska fånga upp ett intresse på kort tid. I den här mässfilmen har vi även inkluderat en showreel som visar några utav de projekt som har gjorts av studenter på BTH. / Our work with the Bachelors thesis has resulted in nine short informational movies which have as a purpose to give information about BTH ( Blekinge Institute of Technology ), and the region to interested people. Four of these movies include information on the region, living/transportation, the school and the social amenities provided for the students. We have also made four movies about different students from BTH. We want to show that there are students from Kiruna in the north to Lund in the south, and that there are many different kinds of people you can meet when you begin your time as a student here. Due to the fact that there are nine different movies there will be variation, and you will accept the information in a better way than in traditional informational movies. Last but not least, we made an event movie which does not include a speaker text but instead communicates through the clips and the music in it. In this movie there is also a showreel with different projects from students on BTH. / Detta är en reflektionsdel till en digital medieproduktion.

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