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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.
11

Responses of accessions of Austrodanthonia spp. to factors associated with soil acidity

Islam, Mohammed Anowarul January 2003 (has links)
Pasture plants already adapted to acidic soil conditions are required as part of an integrated approach (with lime amelioration) to managing acid soils on the Tablelands of New South Wales, Australia. The objective of this thesis is to evaluate the usefulness of Austrodanthonia species for this purpose. The material evaluated in this study was collected during a previous survey of the distribution of Austrodanthonia on the Central, Southern and Monaro Tablelands of New South Wales. It was hypothesised that the genus Austrodanthonia has a wide range of tolerance to acid soils. A series of experiments that provided information on the growth and physiology of Austrodanthonia in relation to soil acidity, with a view to the identification and eventual domestication of the most promising plant material have been conducted through pot, hydroponics and field investigations. Firstly, soils were acidified or limed to obtain a range of soil pH and Al concentrations. This experiment showed that adding aluminium sulfate and calcium carbonate followed by washing excess salts with water is a simple, rapid and convenient method for adjusting soil pH for pot experiments. The pH of the amended soils remained relatively unchanged eight months after treatment. The experimental set-up also resulted in a wide range of soluble Al (2-52 mg/kg) across the soils. The relative Al-tolerance of 183 accessions from 15 Austrodanthonia species was tested in a pot experiment using a range of soil pH. Emergence, survival and growth of all accessions were drastically reduced by high soil acidity (pH 3.9, P < 0.001). About 11% of plants emerged at pH 3.9, whereas at pH 4.4 and 5.3, ~72% of plants emerged. Accessions exhibited large variation within and between species in their tolerance to soil acidity. From the species/accessions tested, 49 accessions from eight species were selected for further study (on the basis of being more acid tolerant). Hydroponic experiments conducted in the glasshouse evaluated: (i) formulation of nutrient solution with a stable pH, (ii) effectiveness of the formulation using tap water and deionised water and (iii) estimation of free ion activities of Al and Mn in the nutrient solution and their effects on Austrodanthonia growth. These experiments showed that a NO3-N/NH4-N ratio of 9:4 is the most appropriate ratio to obtain a stable pH 4.0 without affecting plant growth; that there was little difference between tap water and deionised water on the ionic effects of Al and Mn, and plant-size did not play a role on accession survival and that accessions of Austrodanthonia could grow well within a wide range of pH (3.5-5.5), Al (50-250 �M) and Mn (100-2000 �M). Growth of Austrodanthonia accessions declined under high acidity (pH < 3.5) and Al (300 �M), but tolerated high concentrations of Mn (2000 �M). Root-tips stained with hematoxylin grouped accessions in a similar way to the pot and hydroponic experiments for most of the accessions tested. The intensity of root staining with hematoxylin and the differential distribution of Al in the shoots and roots provided an indication that different tolerance mechanisms may be involved with Austrodanthonia accessions. It appears that both exclusion and internal mechanisms may operate for Al- and Mn-tolerance. A field experiment was conducted at Carcoar (33037�S, 149013�E, elevation 800 m) using gradients in soil pH and Al available on-site to grow selected accessions of Austrodanthonia. The accessions exhibited a range of responses to soil acidity. The accession responses to acidity from the pot and hydroponic experiments were similar to those obtained in the field, especially where Al was present as a low Al-challenge. Overall, this study shows that Austrodanthonia exhibits a wide range of acid tolerance between species and accessions within species. Among the species tested, A. duttoniana and A. fulva appeared to have the greatest commercial potential, because of their productivity and acid tolerance. The variability that exists in the accessions may be exploitable in breeding and selection programs for improved cultivars.
12

Tolerância de variedades de cana-de-açúcar (Saccharum spp.) à toxidez por alumínio em solução / Tolerance of sugarcane (Saccharum spp.) varieties to aluminum toxicity in solution

Oliveira, Mariane de Souza 24 February 2012 (has links)
Made available in DSpace on 2016-06-02T18:55:23Z (GMT). No. of bitstreams: 1 4194.pdf: 5569130 bytes, checksum: ebe68f310cd510f98aabaf88b820d952 (MD5) Previous issue date: 2012-02-24 / Universidade Federal de Minas Gerais / The influence of toxic aluminum (Al) on root development and absorption of water and nutrients has been identified as a major cause of low productivity of many soils. The theoretical and experimental study on the tolerance of varieties of sugarcane to adverse conditions of extreme acidity and, especially, high Al saturation, is still inconclusive The objectives of this study were: to develop and propose an experimental protocol for the study tolerance of varieties of sugarcane to Al in solution and to study the sensitivity of nine varieties of sugarcane (RB928064, RB966928, RB937570, RB855156, RB855453, RB935744, RB867515, RB925345, SP813250) to Al stress solution through a series of analyzes: (a) review the allocation of the Al at the tip roots, (b) observation of the root apices and (c) root growth; identify the main changes in the root; identify the critical dose to the Al root growth and identify the most efficient method for the classification of varieties on the Al in solution. The experiment was conducted in laboratory conditions in a completely randomized design with three replications. After the germination period, the mini-stalks of sugarcane were acclimated in tanks with nutrient solution. After six days, the mini-cuttings were transferred to containers with nutrient solution and increasing doses of Al (0, 130, 380, 500, 800, 1000, 1400, 2000, 3000 and 4000 &#956;mol L -¹), where they remained for six days and subsequently were removed for analyzes. The development of the experimental protocol was efficient for the evaluation of tolerance and its main factors were germination method, selecting the range of Al concentration in solution and the methods of tolerance assessment. The varieties differed in Al tolerance according to the analyzes. The main changes of the tip root were mucilage production, loss of epidermal cells of the root cap and its disintegration, and brown staining of root tips. The root elongation rate (TAR) depended on the interaction between variety and concentration of Al, and, for the varieties studied, the critical value ranged from 130 to 3000 &#956;mol L-¹. The TAR method was considered more efficient to evaluate the tolerance of varieties of sugarcane to Al in solution and in accordance with this method the varieties were classified as tolerance in the following order: RB928064 > RB935744 > RB855453 = RB966928 > RB925345 = RB867515 > SP813250 > RB855156 > RB937570. / A influência da toxidez por alumínio (Al) sobre o desenvolvimento do sistema radicular e a absorção de água e de nutrientes tem sido apontada como uma das principais causas da baixa produtividade de muitos solos. O referencial teórico e experimental sobre a tolerância de variedades de cana-de-açúcar a condições adversas de acidez extrema e, principalmente, à alta saturação por Al, ainda é inconclusivo Os objetivos deste estudo foram: desenvolver e sugerir um protocolo experimental para o estudo da tolerância de variedades de cana-de-açúcar ao Al em solução; estudar a sensibilidade de 9 variedades de cana-de-açúcar (RB928064, RB966928, RB937570, RB855156, RB855453, RB935744, RB867515, RB925345 e SP813250) ao estresse por Al em solução através de um conjunto de análises: (a) exame da alocação do Al na extremidade das raízes; (b) observação do ápice radicular e (c) crescimento radicular; identificar as principais alterações na raiz; identificar a dose crítica de Al ao crescimento radicular e identificar o método mais eficiente para a classificação das variedades quanto ao Al em solução. O experimento foi conduzido em condições de laboratório em delineamento inteiramente casualizado, com três repetições. Após o período de germinação, os mini-toletes de cana-de-açúcar foram aclimatados em tanques com solução nutritiva. Após seis dias, os mini-toletes foram transferidos para recipientes com solução nutritiva e doses crescentes de Al (0, 130, 380, 500, 800, 1000, 1400, 2000, 3000 e 4000 &#956;mol L-¹), onde permaneceram por seis dias e posteriormente foram retirados para análises. O desenvolvimento do protocolo experimental foi eficiente para a avaliação da tolerância e seus principais fatores foram método de germinação, seleção da faixa de concentração de Al em solução e os métodos de avaliação da tolerância. As variedades apresentaram diferenças quanto à tolerância ao Al de acordo com as análises realizadas. As principais alterações dos ápices radiculares foram a produção de mucilagem, perda de células epidérmicas da coifa, desintegração da coifa e coloração parda. A taxa de alongamento radicular (TAR) dependeu da interação entre variedade e concentração de Al, sendo que, para as variedades estudadas, o valor crítico variou de 130 a 3000 &#956;mol L-1. O método de TAR foi considerado o mais eficiente para a avaliação da tolerância de variedades de cana-de-açúcar ao Al em solução e de acordo com esse método as variedades foram classificadas quanto a tolerância na seguinte ordem: RB928064 > RB935744 > RB855453 = RB966928 > RB925345 = RB867515 > SP813250 > RB855156 > RB937570.
13

Distribuição do neuroepitélio olfatório em concha média e superior em cadáveres humanos / Distribution of olfactory neuroepithelium in the middle and superior turbinate of human cadavers

Pinna, Fabio de Rezende 03 September 2008 (has links)
INTRODUÇÃO: A biópsia do neuroepitélio olfatório (NeuO) oferece perspectivas para aplicações terapêuticas tanto em doenças do olfato como doenças neurodegenerativas. Uma coleta bem sucedida desse tecido in vivo ainda não é rotina, devido á carência de estudos sobre a distribuição do NeuO em conchas superior (CS) e média (CM). Neste trabalho, descrevemos a distribuição do NeuO na CS e CM em cadáveres a partir da retirada integral dessas estruturas e posterior análise histológica por coloração de hematoxilina e eosina (HE) e imunoistoquímica. Além disso, também analisamos a influência do sexo, idade e lateralidade no grau de presença do NeuO nas CS e CM. CASUÍSTICA E MÉTODOS: Estudo anatômico prospectivo realizado de março de 2006 a janeiro de 2008. A CS e a CM foram endoscopicamente retiradas de um total de 25 cadáveres frescos com menos de 12 horas de óbito. Cada concha foi seccionada na metade de seu comprimento ântero-posterior. Assim, cada um dos 25 cadáveres deu origem a oito fragmentos de mucosa de regiões anatômicas distintas, totalizando 200 lâminas para análise tanto por coloração de HE como por reação de imunoistoquímica. Nas lâminas coradas por HE, classificamos a distribuição do NeuO em graus 0, 1, 2, 3, 4, sendo que a análise foi realizada por 3 patologistas de forma cega. Para imunoistoquímica, só obtivemos positividade com a proteína S-100. A concordância entre os três patologistas foi avaliada aos pares utilizando-se o coeficiente de Kappa. A distribuição do NeuO foi analisada de acordo com a idade, sexo, tempo de óbito, simetria entre as fossas nasais e acurácia da imunoistoquímica. RESULTADOS: Pela HE na CS, o NeuO esteve presente em 82,9% das vezes e, na CM, em 17,1%. Na CS, o NeuO foi detectado em 82,9 % das lâminas, 4,9 vezes a prevalência na CM, que foi de 17,1 % das lâminas (p < 0,001). Pela imunoistoquímica, foi possível encontrar NeuO em um total de 15 fragmentos. Desses, 10 (20%) eram da metade posterior da CS e cinco (7,6%) da metade anterior da CS. Pelo cálculo da razão de prevalência, temos que a chance de encontrar NeuO é 4,9 vezes maior na CS do que na CM (IC95%: 3,3 7,4). Dos 15 fragmentos com marcação positiva para proteína S-100, sete corresponderam aos que tinham uma distribuição grau 3 (>50% e 75%) pela HE e outros sete aos que tinham uma distribuição grau 4 (acima de 75%). Somente um fragmento teve marcação positiva para imunoistoquímica no grupo 2 (entre 26 e 50%) na HE. A proteína S-100 apresentou uma sensibilidade de 13,5% e especificidade de 100% para detecção de NeuO. Não houve diferença estatisticamente significante na prevalência de NeuO quando os fragmentos foram divididos de acordo com o sexo, idade de óbito e lado da fossa nasal. No entanto, ao analisarmos a presença de NeuO de acordo com o grau de distribuição entre cada lado, não se percebe uma concordância. CONCLUSÕES: A quantidade total de NeuO foi simetricamente distribuída entre as fossas nasais, mas não houve uma concordância entre os lados quanto à maneira como o NeuO está distribuído. O NeuO apresenta maior probabilidade de ser encontrado na metade posterior de CS. A HE é um método eficaz para distinção entre NeuO e epitélio respiratório, devido a grande concordância entre três patologistas distintos. / INTRODUCTION: Olfactory neuroepithelium (ON) biopsy provides perspectives for several therapeutic applications, both in disorders of olfaction and in neurodegenerative diseases. Successful in vivo collection of ON is still not routine, due to a dearth of studies on ON distribution in the superior and middle turbinate (ST and MT respectively). This study describes the distribution of ON in cadaver ST and MT as determined by complete endoscopic removal of turbinates and histological analysis with hematoxylin and eosin (H&E) and immunohistochemical staining. We also analyzed the influence of gender, age, and naris side on the extent to which ON is present in the superior and middle turbinate. CASE SELECTION AND METHODS: We conducted a prospective anatomical study from March 2006 to January 2008. The superior and middle turbinates of 25 fresh cadavers (less than 12 hours post-mortem) were removed endoscopically. Each turbinate was halved into anterior and posterior fragments. Eight anatomically distinct fragments were therefore obtained from each of the 25 cadavers for a total of 200 specimens, which were analyzed through H&E staining and immunohistochemistry. Hematoxylin and eosin-stained slides were subjected to blind examination by three independent pathologists; ON distribution was graded on a fivepoint numeric scale (grade 0, 1, 2, 3, or 4). Immunohistochemistry was only positive through S-100 staining. Pairwise agreement between pathologists was assessed by means of the Kappa coefficient. The distribution of ON was analyzed regarding age, gender, time elapsed between death and specimen harvesting, symmetry between nares, and accuracy of immunohistochemistry results. RESULTS: In H&E-stained slides, olfactory neuroepithelium was present in 82.9% of ST and 17.1% of MT specimens; prevalence in the superior turbinate was therefore 4.9-fold greater (p < 0.001). Immunohistochemical analysis was able to identify ON in 15 fragments, 10 of which (20%) were from the posterior half of the superior turbinate; the remaining five specimens (7.6%) were from the anterior ST. According to prevalence ratio, the odds of finding ON are 4.9 times greater in superior turbinate than in the middle turbinate (CI, 95%; 3.37.4). Of the 15 immunohistochemistry-positive fragments, seven were assigned distribution grade 3 (>50% and 75% presence of ON) on H&E staining seven others were graded 4 (>75% presence of ON). A single immunohistochemistrypositive fragment was found to have grade 2 ON distribution (i.e., it contained 26% to 50% olfactory neuroepithelium) on H&E staining. S-100 staining showed a sensitivity of 13.5% and specificity of 100% for ON detection. There was no statistically significant difference in ON prevalence when fragments were compared according to gender, age at time of death, and naris side. However, when we analyzed ON presence according to the degree of ON distribution in each side, we found no concordance. CONCLUSIONS: Total ON was distributed symmetrically between nares, but we found no concordance between sides in the manner in which ON is distributed. ON is most likely to be found in the posterior half of the superior turbinate. Hematoxylin and eosin (H&E) staining is an effective method for distinguishing ON from respiratory epithelium, as shown by high inter-rater agreement among three independent pathologists
14

Distribuição do neuroepitélio olfatório em concha média e superior em cadáveres humanos / Distribution of olfactory neuroepithelium in the middle and superior turbinate of human cadavers

Fabio de Rezende Pinna 03 September 2008 (has links)
INTRODUÇÃO: A biópsia do neuroepitélio olfatório (NeuO) oferece perspectivas para aplicações terapêuticas tanto em doenças do olfato como doenças neurodegenerativas. Uma coleta bem sucedida desse tecido in vivo ainda não é rotina, devido á carência de estudos sobre a distribuição do NeuO em conchas superior (CS) e média (CM). Neste trabalho, descrevemos a distribuição do NeuO na CS e CM em cadáveres a partir da retirada integral dessas estruturas e posterior análise histológica por coloração de hematoxilina e eosina (HE) e imunoistoquímica. Além disso, também analisamos a influência do sexo, idade e lateralidade no grau de presença do NeuO nas CS e CM. CASUÍSTICA E MÉTODOS: Estudo anatômico prospectivo realizado de março de 2006 a janeiro de 2008. A CS e a CM foram endoscopicamente retiradas de um total de 25 cadáveres frescos com menos de 12 horas de óbito. Cada concha foi seccionada na metade de seu comprimento ântero-posterior. Assim, cada um dos 25 cadáveres deu origem a oito fragmentos de mucosa de regiões anatômicas distintas, totalizando 200 lâminas para análise tanto por coloração de HE como por reação de imunoistoquímica. Nas lâminas coradas por HE, classificamos a distribuição do NeuO em graus 0, 1, 2, 3, 4, sendo que a análise foi realizada por 3 patologistas de forma cega. Para imunoistoquímica, só obtivemos positividade com a proteína S-100. A concordância entre os três patologistas foi avaliada aos pares utilizando-se o coeficiente de Kappa. A distribuição do NeuO foi analisada de acordo com a idade, sexo, tempo de óbito, simetria entre as fossas nasais e acurácia da imunoistoquímica. RESULTADOS: Pela HE na CS, o NeuO esteve presente em 82,9% das vezes e, na CM, em 17,1%. Na CS, o NeuO foi detectado em 82,9 % das lâminas, 4,9 vezes a prevalência na CM, que foi de 17,1 % das lâminas (p < 0,001). Pela imunoistoquímica, foi possível encontrar NeuO em um total de 15 fragmentos. Desses, 10 (20%) eram da metade posterior da CS e cinco (7,6%) da metade anterior da CS. Pelo cálculo da razão de prevalência, temos que a chance de encontrar NeuO é 4,9 vezes maior na CS do que na CM (IC95%: 3,3 7,4). Dos 15 fragmentos com marcação positiva para proteína S-100, sete corresponderam aos que tinham uma distribuição grau 3 (>50% e 75%) pela HE e outros sete aos que tinham uma distribuição grau 4 (acima de 75%). Somente um fragmento teve marcação positiva para imunoistoquímica no grupo 2 (entre 26 e 50%) na HE. A proteína S-100 apresentou uma sensibilidade de 13,5% e especificidade de 100% para detecção de NeuO. Não houve diferença estatisticamente significante na prevalência de NeuO quando os fragmentos foram divididos de acordo com o sexo, idade de óbito e lado da fossa nasal. No entanto, ao analisarmos a presença de NeuO de acordo com o grau de distribuição entre cada lado, não se percebe uma concordância. CONCLUSÕES: A quantidade total de NeuO foi simetricamente distribuída entre as fossas nasais, mas não houve uma concordância entre os lados quanto à maneira como o NeuO está distribuído. O NeuO apresenta maior probabilidade de ser encontrado na metade posterior de CS. A HE é um método eficaz para distinção entre NeuO e epitélio respiratório, devido a grande concordância entre três patologistas distintos. / INTRODUCTION: Olfactory neuroepithelium (ON) biopsy provides perspectives for several therapeutic applications, both in disorders of olfaction and in neurodegenerative diseases. Successful in vivo collection of ON is still not routine, due to a dearth of studies on ON distribution in the superior and middle turbinate (ST and MT respectively). This study describes the distribution of ON in cadaver ST and MT as determined by complete endoscopic removal of turbinates and histological analysis with hematoxylin and eosin (H&E) and immunohistochemical staining. We also analyzed the influence of gender, age, and naris side on the extent to which ON is present in the superior and middle turbinate. CASE SELECTION AND METHODS: We conducted a prospective anatomical study from March 2006 to January 2008. The superior and middle turbinates of 25 fresh cadavers (less than 12 hours post-mortem) were removed endoscopically. Each turbinate was halved into anterior and posterior fragments. Eight anatomically distinct fragments were therefore obtained from each of the 25 cadavers for a total of 200 specimens, which were analyzed through H&E staining and immunohistochemistry. Hematoxylin and eosin-stained slides were subjected to blind examination by three independent pathologists; ON distribution was graded on a fivepoint numeric scale (grade 0, 1, 2, 3, or 4). Immunohistochemistry was only positive through S-100 staining. Pairwise agreement between pathologists was assessed by means of the Kappa coefficient. The distribution of ON was analyzed regarding age, gender, time elapsed between death and specimen harvesting, symmetry between nares, and accuracy of immunohistochemistry results. RESULTS: In H&E-stained slides, olfactory neuroepithelium was present in 82.9% of ST and 17.1% of MT specimens; prevalence in the superior turbinate was therefore 4.9-fold greater (p < 0.001). Immunohistochemical analysis was able to identify ON in 15 fragments, 10 of which (20%) were from the posterior half of the superior turbinate; the remaining five specimens (7.6%) were from the anterior ST. According to prevalence ratio, the odds of finding ON are 4.9 times greater in superior turbinate than in the middle turbinate (CI, 95%; 3.37.4). Of the 15 immunohistochemistry-positive fragments, seven were assigned distribution grade 3 (>50% and 75% presence of ON) on H&E staining seven others were graded 4 (>75% presence of ON). A single immunohistochemistrypositive fragment was found to have grade 2 ON distribution (i.e., it contained 26% to 50% olfactory neuroepithelium) on H&E staining. S-100 staining showed a sensitivity of 13.5% and specificity of 100% for ON detection. There was no statistically significant difference in ON prevalence when fragments were compared according to gender, age at time of death, and naris side. However, when we analyzed ON presence according to the degree of ON distribution in each side, we found no concordance. CONCLUSIONS: Total ON was distributed symmetrically between nares, but we found no concordance between sides in the manner in which ON is distributed. ON is most likely to be found in the posterior half of the superior turbinate. Hematoxylin and eosin (H&E) staining is an effective method for distinguishing ON from respiratory epithelium, as shown by high inter-rater agreement among three independent pathologists
15

Untersuchung von osteoarthrotisch geschädigten Kiefergelenken an geeigneten Knockout-Maus-Modellen / Analysis of Osteoarthritis in the Temporomandibular Joints of Suitable Knockout Mouse Models

Gajjar, Hetal 03 July 2012 (has links)
No description available.

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