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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Conséquences de l'incompatibilité végétative et de l'infection virale sur l'écologie et l'évolution de l'interaction Cryphonectria parasitica X Cryphonectria Hypovirus

Brusini, Jérémie 09 July 2009 (has links)
Le système d'incompatibilité végétative a été décrit chez tous des champignons (Eumycètes) comme intervenant dans la limitation des fusions somatiques entre conspécifiques. Chez les champignons la fusion somatique est uniquement possible entre individus de même GCV (Groupe de Compatibilité Végétative). Comme tous les systèmes de reconnaissance du soi, le fonctionnement du système d'incompatibilité végétative des champignons est basé sur une grande diversité allélique. Cette thèse propose d'étudier la relation qui semble exister entre cette diversité des gènes impliqués dans l’incompatibilité végétative des champignons et la pression parasitaire exercée par des éléments cytoplasmiques délétères (ou DCE) transmis lors des fusions somatiques. Trois problématiques ont été abordées, avec trois approches différentes : (1) une approche conceptuelle générale portant sur l’évolution des systèmes de reconnaissance du soi, (2) une approche de modélisation sur le maintien de la diversité en GCV de la population de champignon par un DCE et (3) une approche expérimentale, pour étudier d’une part la perméabilité de la barrière d‘incompatibilité végétative et d’autre part l’interaction C. parasitica/CHV et les liens existant entre transmission et virulence du CHV. Ces études ont permis de montrer l'importance de la perméabilité de la barrière d'incompatibilité végétative à la fois au niveau du maintien de la diversité génétique de la population d'hôte et au niveau de la prévalence des DCE. Il semblerait donc que les DCE évoluent vers des niveaux de virulence faible du fait de la limitation de leur transmission par le système d'incompatibilité végétative de leur hôte. Nos résultats expérimentaux suggèrent que lorsque la diversité en GCV de la population d'hôte est faible, la virulence des DCE pourrait évoluer suivant le modèle du trade-off impliquant une évolution vers un niveau de virulence intermédiaire optimal. Ces travaux permettent donc de mieux comprendre les mécanismes agissant sur l'écologie et l'évolution des interactions champignon/DCE qui, au vu de cette étude, apparaissent comme de bon modèles pour l’étude des systèmes hôtes/parasites. / Vegetative incompatibility systems have been described in Fungi as controlling somatic fusion between conspecifics. For fungi, only fungi of the same vc type can fuse together. As other self recognition systems, this system involved high allelic diversity at specific genes. The issue of this work is to study the cause and effect relationship between the evolution of vegetative incompatibility systems and the selective pressure drove by cytoplasmic deleterious elements, transmitted during somatic fusion. Three problematics with three different approach were done : (1) a conceptual general framework on the evolution of self recognition systems (2) a theoretical work on the maintenance of vc type diversity by DCE and (3) an experimental work on the study of relationship between transmission and virulence in the C. parasitica/CHV host-parasite system. Ours results showed the key role of the permeability of the vegetative incompatibility barrier both for vc type diversity maintenance and on DCE prevalence. DCE would evolve toward avirulence in response to the transmission limitation by host incompatibility systems. Experimental work suggested a positive link between virulence and transmission in some population of CHV when host present a low vc type diversity, which could allow the evolution of the DCE toward an intermediate optimal virulence. This study would shed some light on mechanisms acting on the ecology and the evolution of fungi/DCE interaction which, according to our results, would be good study models for works on host-parasite systems.
212

Sediment removal from urban runoff using seep berms and vegetative filtration

Hamade, Firas Nadim 13 January 2014 (has links)
Previous field demonstration projects in metro-Atlanta have shown that seep berms, which are elongated sedimentation basins at the outlet of a disturbed land area, can provide high suspended sediment trap efficiencies with respect to coarse sediments on construction sites having drainage areas greater than five acres. Previous literature has shown that vegetative filter strips are efficient traps for fine suspended sediment in stormwater runoff. A combination of a seep berm and vegetative filter in series was studied in this thesis as an erosion control measure with quantification of its flow resistance and sediment removal efficiency. First, a field demonstration project was implemented to evaluate seep berms as a viable erosion control measure through a side-by-side comparison with the more commonly-used silt fences on construction sites with drainage areas less than five acres in metro Atlanta. High suspended sediment trap efficiencies were recorded for the seep berm on two separate sites, and the seep berm was shown to be superior to silt fences with respect to sediment control in the site runoff. Then a vegetative filter was studied in the laboratory in a specially-built flume for that purpose. The relationship between vegetative drag coefficient and various parameters reflecting flow conditions and vegetation density in steady, uniform open channel flow was studied in the flume. Both rigid, emergent vegetation and submerged, flexible vegetation were studied at two different plant densities. The application of porous media flow concepts to open channel flow through vegetation resulted in a collapse of data for vegetative drag coefficient for the various vegetation types and densities into a single relationship when plotted against vegetative stem Reynolds number. Point velocity and turbulence intensity profiles at different locations in the vegetative filter were recorded with an acoustic Doppler velocimeter to observe the turbulence structure of the flow and its effects on vegetative drag and settling of sediment. A sediment slurry consisting of a suspension of fine sand was fed into the flume, and an automated sampler was used to measure suspended sediment concentrations along the vegetative filter length for a series of discharges from which sediment flux and trap efficiency could be determined. Experimental data for trap efficiency were plotted against a dimensionless settling efficiency for each type of vegetation and density. These relationships, along with the one developed for the coefficient of drag, were applied in a numerical design technique that allows designers to determine the flow depth, velocity and trap efficiency of a vegetative filter of known dimensions for a given flow rate, sediment grain size distribution, slope, and vegetation density. In a typical design example, the combined trap efficiency proved that a seep berm followed by a vegetative filter can be a very effective erosion control measure.
213

Obrat nadzemní biomasy dominanty ostřicového slatiniště / Turnover of aboveground biomass of the dominant of a sedge fen

MEJDOVÁ, Markéta January 2012 (has links)
Annotation This thesis is part of Project of the Grant Agency of the Czech Republic No. P504/11/1151 (Role of plants in the greenhouse gas budget of a sedge fen) aims at estimating the turnover of aboveground biomass of Carex acuta L. in a flooded part of the Wet Meadows near Třeboň. The biomass turnover was estimated using both destructive and non-destructive types of measurement and was assessed separately for generative and vegetative tillers, which markedly differ in their life cycles. Vegetative tillers last throughout the vegetation season. Generative tillers have a fast development at the beginning of the vegetatin season but die out soon after seed development. They disapper from the stand in mid-July. Vegetative shoots reached their maximum aboveground biomass at the end of June. The average dry weight of all leaves produced so far was 1,51 g per tiller and the average dry weight of all aboveground biomass produced per tiller was 2,28 g. The turnover coefficient was 1,39 year-1 and 1,01 year-1 for leaves and whole tillers, respectively. Also generative shoots reached their maximum aboveground biomass at the end of June. The average dry weight of aboveground biomass produced so far was 1,95 g per tiller. The turnover coefficient was 1, 38 year-1and 1,10 year-1.
214

Padrões de crescimento e produção de cultivares de pereiras europeias sobre portaenxertos de marmeleiro / Standards of growth and production of cultivars of european pear trees on quince rootstocks

Machado, Bruno Dalazen 07 October 2014 (has links)
Made available in DSpace on 2016-12-06T17:42:05Z (GMT). No. of bitstreams: 1 PGPV14DA009.pdf: 2537608 bytes, checksum: 52becf46e22999496c3c26525a0865d0 (MD5) Previous issue date: 2014-10-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The culture of pear (Pyrus communis L.), has great potential for expansion in Southern Brazil due to climate and soil conditions. The lack of information regarding the (s) best (s) combination (s) of european pear cultivars scion and quince rootstocks as vegetative aspect and productive potential has limited the cultivation of pear in the country. In this contexto, the objetive was to evaluate the agronomic aspects of vegetative and productive cultivars scioneuropean pear (Pyrus communis. L) grafted on quince rootstocks (Cydonia oblonga. L) in médium systems, super and high planting densities, at conditions the conditions of the Santa Catarina plateau. The experiments were conducted in the área of company experimental Agrícola Fraiburgo S/A, located in Urupema, state of Santa catarina, during the cropping cycles 2011/12, 12/23 and 13/14. In Chapter I, we used three systems, characterized as average (2500 plants ha¯¹), high (5000 plants ha¯¹) and super (7500 plants ha¯¹) densities. In médium density system, the combinations evaluated among european pear cultivars and quince rootstocks were: Abbè Fetel/Adams Conference/Adams, Clapp s Favourite/EMA, Santa Maria/Adams, rocha/Adams, Packham s Triumph/Adams, Decana du Comice/Adams e Packam s Triumph/EMA. In high density planting combinations were evaluated: Conference/EMC, Clapp s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William s/EMC e Packham s/EMA. In the super density, evaluated the combinations: Rocha/Adams, Santa Maria/Adams, Packam s Triumph/EMC, Abbè Fetel/EMC, Abbè Fetel/Adams and Rocha/EMC. In Chapter II, we evaluated the compartibility of grafting, which consisted in the analysis of growth and vascular grafting connection in the following combinations: Abbè Fetel/Adams, Decana du Comice/Adams, Clapp s Favourite/EMA, Rocha/Adams, Packham s Triumph/EMA and Santa Maria/Adams density of 2500 plants ha¯¹ and Rocha/EMC, Abbè Fetel/EMC and William s/EMC density of 5000 plants ha¯¹. In chapter III, we evaluated the distribution of the root system of diferente combinations of european pear cultivars scion and quince rootstocks at planting density of 2500 plants ha¯¹ with the following combinations: Abbè Fetel/Adams, Clapp s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Decana du Comice/Adams and Packham s Triumph/EMA and density of 5000 plants ha¯¹: Conference/EMC, Clapp s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William s/EMC e Packham s Triumph/EMA. The combination Abbè Fetel/Adams is more vigorou, reporting low yield in médium super system and planting density. The combination Santa Maria grafted on quince Adams gives intermediate vegetative growth of plants and high producrtivity in médium system and super planting density. Combinations Clapp s Favourite/EMA and William s/EMC are incompatible with quince rootstocks of tested, it is possible to observe a clear discontinuity in the region of vascular graft union. Santa Maria and Rocha grafted on quince Adams exhibit a continous vascular union between cultivar and rootstock, with no symptoms of vascular disruption at any level. In planting density of 2500 plants ha¯¹, to jointly analyse the six combinations of european pear cultivars and quince rootstocks throught the spatial distribution of root length at depth, there was a higher concentration of roots in the first 40 cm of depth. Regarding the effective depth, it was observed that up to 40 cm depth concentrate 80% of the total root for all combinations of the average and six combinations evaluated, 83% of root geowth is located on the respective depth. Regarding the effective distance, it was observed that the distance at which are 80% of total root length was 80 cm for all combinations exceptd the Clapp s FAvourite/EMA, which the effective distance was 100 cm. Irt was observed that the average of the six combinations,86% of root growth in horizontal distance located up to 80 cm. Already at a density of 5000 plants ha¯¹ jointly analyzing the six combinations of euroepean pears cultivars and rootstocks quince, it was observed that the greatest concentration of the first roots 40 cm deep, about 90% of the distribution root. Regarding combinations evaluated, it was observed that cv. Packham s Triumph grafted on quince EMA provided greater root growth, and may infer that their combination, compared to the other, exploring a greater volume of soil in the planting density of 5000 plants ha¯¹ and is able to check out the shoot of plant vigor. Regarding the effective depth, it was observed that up to 30 cm deep focus 80% of total root length, evaluated for all combinations except the comnbination William s/EMC that got in this depth, only 60% of root volume. For this combination in particular, has been considered effective depth of 40 cm. As the density of 2500 plants ha¯¹ at a density of 5000 ha¯¹ plants, the major root length also concentrated in the largest amount of available nutrientes and water to the roots region, which should ensure a greater capacity of the plant cultivation of the soil, and thus greater absorption of water nutrients / A cultura da pereira (Pyrus communis. L), possui potencial de expansão em algumas regiões do sul do Brasil, devido às condições climáticas e de solo. A despeito disso, a carência de informações a respeito da(s) melhor(es) combinação(ões) entre cultivares copa de pereiras europeias e portaenxertos de marmeleiro quanto ao aspecto vegetativo e ao potencial produtivo tem limitado a produção de pera no país. Neste contexto, o objetivo do trabalho foi avaliar agronomicamente os aspectos vegetativos e produtivos de cultivares copa de pereiras europeias (Pyrus communis. L) enxertadas sobre portaenxertos de marmeleiro (Cydonia oblonga. L) em sistemas de média, alta e super densidades de plantio, nas condições edafoclimáticas da região do planalto catarinense. Os experimentos foram conduzidos na área experimental da empresa Agrícola Fraiburgo S/A, localizada na cidade de Urupema, estado de Santa Catarina, durante os ciclos de cultivo 2011/12, 12/13 e 13/14. No capítulo I, utilizou-se três sistemas, caracterizados como média (2500 plantas ha-1), alta (5000 plantas ha-1) e super (7500 plantas ha-1) densidades de plantio. No sistema de média densidade, as combinações avaliadas entre cultivares de pereiras europeias e portaenxertos de marmeleiro foram: Abbè Fetel/Adams, Conference/Adams, Clapp´s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Packham´s Triumph/Adams, Decana du Comice/Adams e Packham´s Triumph/EMA. Na alta densidade de plantio, foram avaliadas as combinações: Conference/EMC, Clapp´s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William´s/EMC e Packham´s Triumph/EMA. Já na super densidade, avaliaram-se as combinações: Rocha/Adams, Santa Maria/Adams, Packham´s Triumph/EMC, Abbè Fetel/EMC, Abbè Fetel/Adams e Rocha/EMC. No capítulo II, avaliou-se a compatibilidade de enxertia, que consistiu na análise de crescimento e conexão vascular no ponto de enxertia das seguintes combinações: Abbè Fetel/Adams, Decana du Comice/Adams, Clapp´s Favourite/EMA, Rocha/Adams, Packham´s Triumph/EMA e Santa Maria/Adams na densidade de 2500 plantas ha-1 e Rocha/EMC, Abbè Fetel/EMC e William´s/EMC para a densidade de 5000 plantas ha-1. No capítulo III, avaliou-se a distribuição do sistema radicular das diferentes combinações de cultivares copa de pereiras europeias e portaenxertos de marmeleiro. Na densidade de plantio de 2500 plantas ha-1, utilizou-se as seguintes combinações: Abbè Fetel/Adams, Clapp´s Favourite/EMA, Santa Maria/Adams, Rocha/Adams, Decana du Comice/Adams e Packham´s Triumph/EMA enquanto que na densidade de 5000 plantas ha-1: Conference/EMC, Clapp´s Favourite/EMA, Rocha/EMC, Abbè Fetel/EMC, William´s/EMC e Packham´s Triumph/EMA. A combinação Abbè Fetel/Adams é mais vigorosa, reportando baixo rendimento em sistema de média e super densidade de plantio. A combinação Santa Maria enxertada sobre o marmeleiro Adams, confere crescimento vegetativo intermediário às plantas e alta produtividade em sistema de média e super densidade de plantio. As combinações Clapp´s Favourite/EMA e William´s/EMC são incompatíveis com os portaenxertos de marmeleiros testados, sendo possível observar uma clara descontinuidade vascular na região de união do enxerto. Santa Maria e Rocha enxertadas sobre o marmeleiro Adams, apresentam uma união vascular contínua entre cultivar e portaenxerto, não havendo sintomas de descontinuidade vascular em nenhum nível. Para a densidade de plantio de 2500 plantas ha-1, observou-se maior concentração de raízes nos primeiros 40 cm de profundidade. Em relação à profundidade efetiva, observou-se que até 40 cm de profundidade concentram-se 80% do comprimento total de raízes para todas as combinações e que na média das seis combinações avaliadas, 83% da concentração radicular localiza-se na respectiva profundidade. Em relação à distância efetiva, observou-se que a distância na qual se encontram 80% do comprimento total de raízes foi 80 cm para todas as combinações, com exceção da Clapp´s Favourite/EMA, a qual a distância efetiva foi 100 cm. Foi possível observar que na média das seis combinações, 86% da concentração radicular na distância horizontal localiza-se até 80 cm. Já na densidade de 5000 plantas ha-1, analisando conjuntamente as seis combinações de cultivares de pereiras europeias e portaenxertos de marmeleiro, observou-se que há maior concentração de raízes nos primeiros 40 cm de profundidade, cerca de 90 % de toda a distribuição do sistema radicular. Em relação às combinações avaliadas, observou-se que a cv. Packham´s Triumph enxertada sobre o marmeleiro EMA proporcionou maior crescimento de raízes, podendo inferir que a respectiva combinação, comparada às demais, explora um maior volume de solo na densidade de plantio de 5000 plantas ha-1. Em relação à profundidade efetiva, observou-se que até 30 cm de profundidade se concentram 80 % do comprimento total de raízes, para todas as combinações avaliadas, com exceção da combinação William´s/EMC que obteve na respectiva profundidade, apenas 60% de volume radicular. Para esta combinação, a profundidade considerada efetiva foi de 40 cm. Assim como na densidade de 2500 plantas ha-1, na densidade de 5000 plantas ha-1, o maior comprimento radicular também concentrou-se na região de maior quantidade de água e nutrientes disponíveis às raízes, o que deve assegurar à planta maior capacidade de exploração do solo e, por conseguinte, maior absorção de água e nutrientes
215

Možnosti kultivace orchideje Macodes petola technikami in vitro / In vitro cultivation possibilities of orchid Macodes petola

SVOBODOVÁ, Simona January 2007 (has links)
The orchid family covers 90 percent of the rarest plants under protection all over the world. The ecological and economic value of orchids has aroused public awareness. Since vegatitve propagation methods are available, development of in vitro methods are essential for conservation and commercialization of plants. Purposes work was elaboration progress of vegetative multiplication for tropical orchid Macodes petola in conditions in vitro. At research were proof 4 methods, which distinguish in using desinfection, in operating time and in using different nutritive mediums.
216

Efektivita spolupráce rodiny a zdravotnických pracovníků v péči o apalického pacienta. / Effectiveness of cooperation family and health workers in care of apalic coma.

LIŠKOVÁ, Kristina January 2011 (has links)
People can differ in their attitudes toward apalic syndrome patients. Health care staff, however, would always be professional. They deal with a human being, a person who can sense. This fact should form a framework for both health care professionals and patients´ families. Especially nurses should be very sensitive, calm and good-tempered so that they could take adequate care of apalic patients. The empiric part of the thesis was elaborated through qualitative and quantitative research survey. The qualitative method, an interview, was used in the first phase of the survey. The data were collected through semi-structured interviews with the family members of apalic patients and the nurses of health care facilities. Although the interviews for the family members and the nurses differed in some parts, they contained common identification questions and specific information. The interviews were anonymous and consisted of 16 questions for the family members and 10 questions for the nurses.
217

Influência do estresse hídrico, riqueza e abundância de espécies nativas sobre o potencial invasor de uma Poaceae exótica / Influence of desiccation, species richness and species abundance on invasiveness of a exotic Poaceae

MICHELAN, Thaísa Sala 28 May 2011 (has links)
Made available in DSpace on 2014-07-29T16:21:17Z (GMT). No. of bitstreams: 1 Dissertacao parte 1 Thaisa Sala Michelan.pdf: 38222 bytes, checksum: 2f8d3a6cb8df8f1c42d663b0b5323ef6 (MD5) Previous issue date: 2011-05-28 / Exotic species represent strong threats to biodiversity. This concern is especially valid in freshwater ecosystems due to their high biodiversity and the highest rates of extinction, compared with terrestrial and marine ecosystems. The increasing habitat complexity provided by the presence of macrophytes may partially explain the high diversity of aquatic ecosystems. However, depending on the density and other particular characteristics of these plant, the diversity may be negatively affected. In this context, Urochloa subquadripara, a species native to Africa, is an aquatic macrophyte weed occurring in various natural and artificial aquatic ecosystems in America. In a small scale, the occurrence of this exotic species increases with reducing natives species richness; however, in a large scale U. subquadripara invades sites with more richness of native species. This controversy is typical of observational studies in invasion biology and it demand experiments to test effects of abiotic and biotic resistance on the invasive potential of this exotic. Accordingly, two experiments were conducted in order to test the following hypotheses: (i) the regeneration and colonization of U. subquadripara decreases with increasing time of exposure to dry, (ii) fragments of the apical part of this species, when compared with those of the basal part, have higher viability and colonization potential (first experiment) and (iii) the invasiveness of aquatic environments by U. subquadripara is negatively influenced by the richness and abundance of native species (second experiment). Our results supported all of our hypotheses: U. subquadripara showed high resistance to desiccation, and the fragments of the apical part were those which had higher viability and colonization potential. In addition, both richness and abundance of native species affected negatively the invasive potential of this exotic macrophyte. The second experiment demonstrated that the effect of richness and abundance limited the development of U. subquadripara, although such effect was not sufficient to prevent the invasion of macrophyte communities by this species. Based on these results, it appears that the population growth of U. subquadripara is greater in disturbed sites, mainly those affected by drought, which in general, have lower abundance and diversity of native species. / Espécies exóticas representam fortes ameaças à biodiversidade. Essa preocupação é especialmente válida em ecossistemas aquáticos continentais em função da elevada biodiversidade e das maiores taxas de extinção, quando comparados com ecossistemas terrestres e marinhos. O aumento da complexidade dos habitats promovido pela presença de macrófitas aquáticas pode explicar em parte a elevada diversidade dos ecossistemas aquáticos. No entanto, dependendo das densidades e de outras características espécies-específicas dessas plantas, a diversidade pode ser negativamente afetada. Nesse contexto, Urochloa subquadripara, espécie nativa da África, é uma macrófita aquática infestante de vários ecossistemas aquáticos naturais e artificiais na América. Em pequena escala espacial, a ocorrência dessa exótica aumenta com a redução do número de espécies nativas, já em grande escala U. subquadripara invade locais com maior riqueza de espécies nativas. Essa controvérsia é típica de estudos observacionais em biologia de invasões sendo necessária a realização de experimentos para testar efeitos da resistência abiótica e biótica sobre o potencial invasor de exóticas. Nesse sentido, foram realizados dois experimentos, com o objetivo de testar as seguintes hipóteses: (i) a regeneração e colonização de U. subquadripara diminui com o aumento do tempo de exposição a seca; (ii) os fragmentos da parte apical dessa espécie, quando comparados com aqueles da parte basal, apresentam maior viabilidade e potencial de colonização (primeiro experimento) e (iii) a invasibilidade de ambientes aquáticos por U. subquadripara é influenciada negativamente pela riqueza e abundância de espécies nativas (segundo experimento). De modo geral, todas as hipóteses foram aceitas: U. subquadripara apresentou alta resistência a dessecação, sendo que os fragmentos da parte apical foram os que apresentaram maior viabilidade e potencial de colonização e tanto a riqueza como a abundância de espécies afetaram negativamente o potencial invasor dessa exótica. Esse último experimento demonstrou que, apesar de limitar o desenvolvimento de U. subquadripara, o efeito da riqueza e abundância de nativas não é suficiente para impedir a invasão de comunidades de macrófitas por essa espécie. Com base nesses resultados, infere-se que o crescimento populacional de U. subquadripara é maior em locais perturbados, principalmente por distúrbios como a seca que, em geral, também apresentam menor abundância e diversidade de espécies nativas.
218

Produção do cuidado a pacientes com condições neurológicas muito graves: contribuições interdisciplinares para uma fundamentação teórica / Care for patients with very severe neurological conditions: interdisciplinary contributions to a theoretical framework

Marilia Bense Othero 31 August 2016 (has links)
A assistência aos pacientes com doenças neurológicas de longa duração não é reconhecida na produção científica brasileira; entende-se por doença neurológica de longa duração: doenças neurológicas de curso longo, fase final de difícil identificação, com sintomas variados e condição de dependência moderada ou grave e comprometimento cognitivo de difícil avaliação. Neste estudo, foram consideradas as seguintes condições: estado vegetativo persistente, estado mínimo de consciência e síndrome do encarceramento (ou síndrome de locked-in). Em busca bibliográfica, verificou-se que não há artigo em língua portuguesa sobre o tema. No cotidiano, a assistência é focada em higiene e observação clínica. Entretanto, na perspectiva do Cuidado, algo mais é necessário ao se pensar este tipo de prática, para a promoção da dignidade humana. Os objetivos deste estudo são: relatar uma prática junto a pessoas com doenças neurológicas de longa duração focada no seu resgate biográfico, e fundamentar a mesma de maneira interdisciplinar, a partir do Cuidado como categoria reconstrutiva. É uma pesquisa qualitativa, na qual foram utilizados primariamente registros de um diário de campo da primeira autora, sobre intervenções em Terapia Ocupacional com esta população; a partir destes, foram produzidas narrativas e reflexões sobre a metodologia de intervenção. A partir do resgate biográfico, busca-se resgatar a condição de sujeito do paciente neurológico muito grave. Na segunda etapa, tem-se a fundamentação teórica numa perspectiva interdisciplinar; o conceito de Cuidado é a referência principal, compreendido como o sentido existencial da experiência de adoecimento. Também foi utilizado o referencial da psicanálise de orientação freudiana e lacaniana para aprofundamento teórico dos achados empíricos descritos através de narrativas. A reconstrução da biografia do paciente ocorre por diversas perspectivas, mas especialmente pela estimulação sensorial - não com foco de recuperação neurológicas, mas a partir do repertório do paciente e em busca da validação de sua condição de sujeito. Junto com uma detalhada avaliação e acompanhamento, o terapeuta faz um monitoramento contínuo, propondo atividades e dando especial atenção ás reações observadas, para que possa nomeá-las ou traduzi-las, bem como discriminar os estímulos agradáveis e desagradáveis; isto também possibilita ampliação das possibilidades de encontro deste sujeito com o mundo. Os conceitos psicanalíticos: estágio do espelho, real, lalíngua e constituição do sujeito apresentam-se como fundamentais para a compreensão das experiências empíricas vividas e, posteriormente, elaboração de uma fundamentação teórica. Memória, história, identidade, dignidade e subjetividade qualificam a prática junto a pessoas com doenças neurológicas de longa duração. A despeito das reações neurológicas apresentadas, tal prática possibilita a reconstrução de um cotidiano significativo e as teorias psicanalíticas de orientação freudiana e lacaniana constituem importante marco para fundamentação da reconstrução da assistência / The care of people with Long Term Neurological Conditions (LTNC) isn´t recognized in the Brazilian Palliative Care scientific production; in daily basis, the assistance is focussed on hygiene´s care and clinical observation. However, from the perspective of palliative care, something more is needed, to promote the dignity of the human person. To describe an occupational therapy intervention for patients with LTNC based on biographical rescue. Records and field diaries of an Occupational Therapy intervention promoted by the first author were used to produce narratives and reflections about this intervention´s methodology. The concept of Comprehensive Care is the main reference, designed as care interested in the existential sense of the illness process. It was also used the framework of Freud´s and Lacan´s psychoanalysis for theoretical studies of the empirical findings reported through narratives. The beginning of the reconstruction of the patient´s biography occurs by several perspectives, especially through sensory stimuli related to prior patient´s occupational repertoire. Along with the detailed evaluation, the therapist does a careful and continuous monitoring, proposing activities, giving special attention to their reactions, being able to discriminate what pleases or not, and expanding the possibilities of encounter of people with LTNC and the environment which surround them. The psychoanalytic concepts: mirror stage, real, lalangue and subject´s constitution had major importance to understand the empirical experiences and to develop a theoretical basis. Memory, history, identity, dignity, and subjectivity qualify the practice of occupational therapist with people with LTNC. Regardless of neurological reactions presented by the patients this practice helps reconstructing the meanings of the daily life of person with so severe disability. Sensory stimuli are shown as potential tools for a reconfiguration of the assistance with someone seriously affected by a neurological disease. Psychoanalytic theories of Freudian and Lacanian orientation are also an important framework for the reconstruction assistance
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Functional Characterization of RFL as a Regulator of Rice Plant Architecture

Deshpande, Gauravi M January 2014 (has links) (PDF)
Poaceae (or Gramineae) belong to the grass family and is one of the largest families among flowering plants on land. They include some of the most important cereal crops such as rice (Oryza sativa), barley (Hordeum vulgare), wheat (Triticum aestivum), maize (Zea mays), and sorghum (Sorghum bicolor). The characteristic bushy appearance of grass plants, including cereal crops, is formed by the activities of axillary meristems (AMs) generated in the leaf axil. These give rise to tillers from the basal nodes which recapitulate secondary growth axis and AMs are formed during vegetative development. On transition to flowering the apical meristem transforming to an inflorescence meristem (IM) which produces branches from axillary meristem. These IM gives rise to branches that ultimately bear florets. Vegetative branching/tillering determines plant biomass and influences the number of inflorescences per plant. While inflorescence branching determines the number of florets and hence seeds. Thus the overall activity of axillary meristems plays a key role in determining plant architecture during both vegetative and reproductive stages. In Arabidopsis, research on the plant specific transcription factor LEAFY (LFY) has pioneered our understanding of its regulatory functions during transition from vegetative to reproductive development and its role in specifying a floral meristem (FM) identity to the newly arising lateral meristems. In the FM LFY activates other FM genes and genes for floral organ patterning transcription factors. LFY is strongly expressed throughout the young floral meristems from the earliest stages of specification but is completely absent from the IM (Weigel et al., 1992). LFY expression can also be detected at low levels in the newly emerging leaf primordia during the vegetative phase, and these levels gradually increase until the floral transition (Blazquez et al., 1997; Hempel et al., 1997). In rice, the LFY ortholog-RFL/APO2 is expressed predominantly in very young branching panicles/ inflorescence meristems (Kyozuka et al., 1998; Prasad et al., 2003) while in the vegetative phase RFL is expressed at axils of leaves (Rao et al., 2008). In rice FMs expression is restricted to primordia of lodicules, stamens, carpels and ovules (Ikeda-Kawakatsu et al., 2012). Knockdown of RFL activity or loss of function mutants show delayed flowering and poor panicle branching with reduced number of florets and lower fertility (Rao et al., 2008, Ikeda-Kawakatsu et al., 2012). In some genotypes reduced vegetative axillary branching is also compromised (Rao et al., 2008). On the other hand RFL overexpression leads to the early flowering, attributing a role as an activator for the transition of vegetative meristems to inflorescence meristems (Rao et al., 2008). Thus, RFL shows a distinct developmental expression profile, has unique mutant phenotypes as compared to Arabidopsis LFY thus indicating a divergence in functions. We have used various functional genomics approaches to investigate regulatory networks controlledby RFL in the vegetative axillary meristems and in branching panicles with florets. These regulatory effects influence tillering and panicle branching, thus contributing to rice plant architecture. RFL functions in axillary meristem Vegetative AMs are secondary shoot meristems whose outgrowth determines plant architecture. In rice, AMs form tillers from basal nodes and mutants with altered tillering reveal that an interplay between transcription factors and the phytohormones - auxin, strigolactone underpins this process. We probed the relationship between RFL and other factors that control AM development. Our findings indicate that the derangements in AM development that occur on RFL knockdown arise from its early effects during specification of these meristems and also later effects during their outgrowth of AM as a tiller. Overall, the derailments of both steps of AM development lead to reduced tillering in plants with reduced RFL activity. Our studies on the gene expression status for key transcription factor genes, genes for strigolactone pathway and for auxin transporters gave an insight on the interplay between RFL, LAX1 and strigolactone signalling. Expression levels of LAX1 and CUC genes, that encode transcription factors with AM specification functions, were modulated upon RFL knockdown and on induction of RFL:ΔGR fusion protein. Thus our findings imply a likely, direct activating role for RFL in AM development that acts in part, through attaining appropriate LAX1 expression levels. Our data place meristem specification transcription factors LAX1 and CUC downstream to RFL. Arabidopsis LFY has a predominant role in conferring floral meristem (FM) identity (Weigel et al., 1992; Wagner, 2009; Irish, 2010; Moyroud et al., 2010). Its functions in axillary meristems were not known until recently. The latter functions were uncovered with the new LFYHARA allele with only partial defects in floral meristem identity (Chahtane et al., 2013). This mutant allele showed LFY can promote growth of vegetative AMs through its direct target REGULATOR OF AXILLARY MERISTEMS1 (RAX1), a R2R3 myb domain factor (Chahtane et al., 2013). These functions for Arabidopsis LFY and RAX1 in AMs development are parallel to and redundant with the pathway regulated by LATERAL SUPPRESSOR (LAS) and REGULATOR OF AXILLARY MERISTEM FORMATION1 (ROX1) (Yang et al., 2012; Greb et al., 2003). Interestingly, ROX1 is orthologous to rice LAX1 and our data show LAX1 expression levels in rice panicles and in culms with vegetative AMs is dependent on the expression status of RFL. Thus, we speculate that as compared to Arabidopsis AM development, in rice the LFY-dependent and LFY-independent regulatory pathways for AMs development are closely linked. In Arabidopsis, CUC2 and CUC3 genes in addition to their role in shoot meristem formation and organ separation play a role in AM development possibly by defining a boundary for the emerging AM. These functions for the Arabidopsis CUC genes are routed through their effects on LAS and also by mechanisms independent of LAS (Hibara et al., 2006; Raman et al., 2008). These data show modulation in RFL activity using the inducible RFL:∆GR protein leads to corresponding expression changes in CUC1/CUC2 and CUC3 genes expression in culm tissues. Thus, during rice AM development the meristem functions of RFL and CUC genes are related. Consequent to specification of AM the buds are kept dormant. Bud outgrowth is influenced by auxin and strigolactone signalling pathways. We investigated the transcript levels, in rice culms of genes involved in strigolactone biosynthesis and perception and found the strigolactone biosynthesis gene D10 and hormone perception gene are significantly upregulated in RFL knockdown plants. Further, bioassays were done for strigolactone levels, where we used arbuscular mycorrhiza colonization assay as an indicator for strigolactone levels in wild type plants and in RFL knockdown plants. These data validate higher strigolactone signalling in RFL knockdown plants. To probe the relationship between RFL and the strigolactone pathway we created plants knocked down for both RFL and D3. For comparison of the tillering phenotype of these double knockdown plants we created plants with D3 knockdown alone. We observed reduced tillering in plants with knockdown of both RFL and D3 as compared to the tiller number in plants with knockdown of D3 alone. These data suggest that RFL acts upstream to D3 of control bud outgrowth. As effects of strigolactones are influenced by auxin transport we studied expression of OsPIN1 and OsPIN3 in RFL knockdown plants. Their reduced expression was correlated with auxin deficiency phenotypes of the roots in RFL knockdown plants. These data in conjunction with observations on OsPIN3 the gene expression modulation by the induction of RFL:∆GR allow us to speculate on a relationship between RFL, auxin transport and strigolactones with regard to bud outgrowth. We propose that the low tillering phenotype of RFL knockdown plants arises from weakened PATS, consequent to low levels of PIN1 and PIN3, coupled with moderate increase in strigolactones. Taken together, our findings suggest functions for RFL during AM specification and tiller bud outgrowth. RFL functions in panicle branching Prior studies on phenotypes of RFL knockdown or loss of function mutants suggested roles for RFL in transition to flowering, inflorescence meristem development, emergence of lateral organs and floral organ development (Rao et al., 2008; Ikeda-Kawakatsu et al., 2012). It has been speculated that RFL acts to suppress the transition from inflorescence meristem to floral meristem through its interaction with APO1 (Ikeda-Kawakatsu et al., 2012). The downstream genes regulated by RFL in these processes have not yet been elucidated. To identify direct targets of RFL in developing panicles we adopted ChIP-seq coupled with studies on gene expression modulation on induction of RFL. For the former we raised polyclonal anti-sera and chromatin from branching panicles with few florets. For gene expression modulation studies, we created transgenics with a T-DNA construct where an artificial miRNA against 3’UTR specifically knocked endogenous RFL and the same T-DNA had a second expression cassette for generation of a chemically inducible RFL-ΔGR protein that is not targeted by amiR RFL. Our preliminary ChIP-seq data in the wild type panicle tissues hints that RFL binds to hundreds of loci across the genome thus providing first glimpse of direct targets of RFL in these tissues. These data, while preliminary, were manually curated to identify likely targets that function in flowering, we summarize here some key findings. Our study indicates a role of RFL in flowering transition by activating genes like OsSPL14 and OsPRMT6a. Recent studies indicate that OsSPL14 directly binds to the promoter of OsMADS56 or FTL1, the rice homologs of SOC1 and FT to promote flowering (Lu et al., 2013). As RFL knockdown plants show highly reduced expression of OsMADS50/SOC1 and for RFT1 (Rao et al., 2008), and we show here RFL can bind and induce OsSPL14 expression we suggest the RFL¬OsSPL14 module can contribute to the transition of the SAM to flowering. Further, OsSPL14 in the young panicles directly activates DENSE AND ERECT PANICLE1 (DEP1) to control panicle length (Lu et al., 2013). Thus RFL-OsSPL14-DEP1 module could explain the role of RFL in controlling panicle architecture (Rao et al., 2008; Ikeda-Kawakatsu et al., 2012). Thus RFL plays a role in floral transition and this function is conserved across several LFY homologs. Our data ChIP-seq in the wild type tissue and gene expression modulation studies in transgenics also give molecular evidences for the role of RFL in suppression of floral fate. The direct binding of RFL to OsMADS17, OsYABBY3, OsMADS58 and HD-ZIP-IV loci and the changes in their transcript levels on induction of RFL support this hypothesis. Once the transition from SAM to FM takes place, we speculate RFL represses the conversion of inflorescence branch meristems to floral fate by negatively regulating OsYABBY3, HD-ZIP class IV and OsMADS17 that can promote differentiation. These hypotheses indicate a diverged function for RFL in floral fate repression. Arabidopsis LFY is known to activate the expression of AGAMOUS (AG), whose orthologs in rice are OsMADS3 and OsMADS58. Our studies confirm conservation with regard to RFL binding to cis elements at OsMADS58 locus that is homologous to Arabidopsis AG. But importantly we show altered consequences of this binding on gene expression. We find RFL can suppress the expression of OsMADS58 which we speculate can promote a meristematic fate. Further, we also present the abnormal upregulation of floral organ fate genes on RFL downregulation. These data too indicate functions of RFL, are in part, distinct from the role of Arabidopsis LFY where it works in promoting floral meristem specification and development. These inferences are supported by our data that rice gene homologs for AP1, AP3 and SEP3 are not directly regulated by RFL, unlike their direct regulation by Arabidopsis LFY during flower development. We also report the expression levels of LAX1, FZP, OsIDS1 and OsMADS34 genes involved in meristem phase change and IM branching are RFL dependent. This is consistent with its role in the suppression of determinacy, thereby extending the IM activity for branch formation. But as yet we do not know if these effects are direct. Together, our data report direct targets of RFL that contribute to its functions in meristem regulation, flowering transition, and suppression of floral organ development. Overall, our preliminary data on RFL chromatin occupancy combined with our detailed studies on the modulation of gene expression provides evidence for targets and pathways unique to the rice RFL during inflorescence development. Comparative analysis of genes downstream to RFL in vegetative tillers Vs panicles Tillers and panicle branches arise from the axillary meristems at vegetative and reproductive stages, respectively, of a rice plant and overall contribute to the plant architecture. Some regulatory factors control branching in both these tissues - for example, MOC1 and LAX1. Mutants at these loci affect tillers and panicle branch development thus indicating common mechanisms control lateral branch primordia development (Li et al., 2003; Komatsu et al., 2003; Oikawa and Kyozuka, 2009). Knockdown of RFL activity or loss-of-function mutants cause significantly reduced panicle branching and in few instances, reduction in vegetative axillary branching (Rao et al., 2008; Ikeda- Kawakatsu et al., 2012). We took up the global expression profiling of RFL knockdown plants compared to wild type plants in the axillary meristem and branching panicle tissue. These data provide a useful list of potential targets of RFL in axillary meristem and branching panicle tissue. The comparative analysis of the genes affected in the two tissues indicates only a subset of genes is affected by RFL in both the vegetative axillary meristems and branching panicle. These genes include transcription factors (OsSPL14, Zn finger domain protein, and bHLH domain protein), hormone signalling molecules (GA2 ox9) and cell signalling (LRR protein) as a set of genes activated by RFL in both tissues. On the other hand, these comparative expression profiling studies also show distinct set of genes deregulated by RFL knockdown in these two tissues therefore implicating RFL functions have a tissue-specific context. The genes deregulated only in axillary meristem tissue only include D3- involved in the perception of strigolactone, OsMADS34 speculated to have a role in floral transition and RCN1 involved in transition to flowering. On the other hand, the genes – CUC1, OsMADS3, OsMADS58 involved in organ development and floral meristem determination were found to be deregulated only in panicle tissues of RFL knockdown plants. These data point towards presence of distinct mechanisms for the development of AMs as tillers versus the development of panicle axillary as rachis branches. Overall, these data implicate genes involved in transition to flowering, axillary meristem development and floral meristem development are controlled by RFL in different meristems to thereby control plant architecture and transition to flowering.
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Etude des effets d’une élévation de température sur la croissance et le développement du pêcher : conséquences sur la qualité des fruits / Effect of a temperature rise on peach growth and development : Consequences on fruit quality

Adra, Fatima 12 July 2017 (has links)
Le dernier rapport du GIEC confirme clairement des projections climatiques prévoyant une augmentation des températures et de leur variabilité à la fin du XXIème siècle. Les effets de ces changements sur la production et la qualité des fruits ont été étudiés dans le cadre du projet CAQ40(INRA). Les expérimentations menées sur des pêchers en pot placés sous différents climats (témoin,+2°C et +5°C), ont permis d’identifier les processus (phénologie, développement, croissance,photosynthèse, métabolisme) les plus sensibles à l’élévation des températures et leurs conséquences sur le développement et la composition des fruits et la pérennité de la production.L’élévation de température a augmenté la demande climatique entraînant une diminution du potentiel hydrique des arbres, ce qui a pu entrainer une concentration des composés d’intérêt dans le fruit. La réduction du taux de photosynthèse des feuilles dans des conditions de forte température est liée à une inhibition de la photosynthèse par les températures élevées et à un contrôle stomatique lié au statut hydrique.Après floraison, l’élévation de température accélère la croissance végétative, induisant une mise en place de la surface foliaire anticipée. Cette croissance végétative précoce a eu pour conséquence (i) une dynamique très rapide d’élongation des axes en pousse longue (ii) une dominance apicale plus marquée, (iii) une diminution de la ramification des axes axillaires,contrairement aux traitements thermiques plus tardifs qui ont eu un effet défavorable sur l’initiation et la différenciation des bourgeons floraux réduisant le potentiel de production l’année suivante.En outre, l’augmentation de température après floraison a entraîné un raccourcissement très marqué de la durée de croissance du fruit, avec une date de récolte anticipée de près de 3semaines. Ce raccourcissement de la durée de croissance du fruit a entraîné une diminution du flux entrant de carbone dans le fruit, pénalisant sa croissance et sa qualité. Le climat très différent entre les deux années expérimentales a entrainé une forte variabilité de la composition des fruits entre les deux années d’expérimentation. En 2014, une élévation de température précoce ou continue a conduit à récolter des fruits de petites tailles ayant des concentrations et des teneurs en saccharose plus importantes. En 2015, la durée de développement entre floraison et maturité était encore plus courte qu’en 2014 ce qui pouvait être lié au climat plus chaud de 2015 et les fruits ont été moins sucrés et plus acides que ceux de 2014. Toutefois, l’élévation des températures en fin de développement en 2015 a augmenté les teneurs et les concentrations en hexoses et en sorbitol liées à un effet concentration mais également à un effet sur le métabolisme. L’élévation des températures en milieu et en fin de cycle a également favorisé l’accumulation d’acide malique et citrique. Les fortes températures n’ont pas eu beaucoup d’effet sur la vitamine C et ont soit augmenté ou diminué les teneurs en composés phénoliques. Les effets d’une élévation de la température sur le métabolisme sont donc très dépendants du stade de développement du fruit.L’utilisation de modèle à l’échelle du fruit (Virtual Fruit) et à l’échelle de l’arbre (QualiTree)pourrait permettre de simuler à la fois l’effet de l’environnement et des pratiques culturales sur la croissance et la qualité du fruit, et donner une vision plus intégrée du fonctionnement de la plante sous contraintes environnementales. / The latest IPCC report clearly confirms the climate projections for increasing temperaturesand their variability at the end of the 21st century. The effects of climate changes in fruit yield andquality have been studied in a project funded by INRA (project CAQ40, Metaprogramme ACCAF).Experiments carried out on potted peaches placed in different climates (control, +2 ° C and + 5 ° C),allowed the identification of the processes (phenology, development, growth, photosynthesis,metabolism) most sensitive to rising temperatures and their consequences on the development andcomposition of fruits and the sustainability of production.Higher temperature has increased the demand for water, leading to a decrease in the waterpotential of the trees, which may have led to a concentration of the compounds of interest in thefruit. The reduction of leaf photosynthesis under high temperature conditions was related to theinhibition of photosynthesis by high temperatures and stomatal control related to water status.After flowering, the rise in temperature accelerates the vegetative growth, triggering a more rapidestablishment of leaf area. This early vegetative growth resulted in: (i) very rapid dynamics ofelongation of the axes in long shoot (ii) a more pronounced apical dominance, (iii) a decrease in theaxillary axial branching. In contrast the later heat treatment had an adverse effect on the initiationand differentiation of floral buds reducing the production potential in the following year.In addition, the increase in temperature after flowering resulted in a marked shortening ofthe fruit growth period, with an expected harvest date almost 3 weeks earlier. This shortening offruit growth duration has led to a decrease in the flow of carbon entering the fruit, penalizing itsgrowth and quality. The very different climates between the two experimental years resulted in ahigh variability in fruit composition between the two years of experimentation. In 2014, increasedtemperature during the early stage of fruit development or continuously led to the harvest ofsmaller fruit with higher concentrations and higher sucrose content. In 2015, the time durationbetween flowering and maturity was even shorter than in 2014, which could be linked to thewarmer climate of 2015. In 2015 fruits were less sweet and acidic than those of 2014. However, therise of temperatures at the end of fruit development in 2015 increased the levels andconcentrations of hexoses and sorbitol; this increase was partially due to a concentration effect butalso to an effect on fruit metabolism. Increased temperatures in the middle and at the end of fruitdevelopment also favoured the accumulation of malic and citric acid. The high temperatures did nothave much effect on vitamin C and either increased or decreased the levels of phenolic compounds.The effects of an increase in temperature on the metabolism are therefore very dependent on thestage of fruit development.The use of a Fruit‐scale model and a tree‐level (QualiTree) model could simulate both the effect ofthe environment and cultural practices on the growth and quality of the fruit, and give a moreintegrated view of the plant's functioning under environmental constraints.

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