No description available.

No description available.

Origin of renal osteodystrophy and cardiovascular complications are multifactorial. This complications are caused by disorders of calcium - phosphate metabolism already at the beginning of patient's irreversible renal failure. The factors playing the most important part in the development o renal ostedystrophy and are hypocalcemia and increasing serum phosphate levels associated with a declining glomerulal filtration. Two main types of renal osteodystrophy can be described - high turnover bone disease and low turnover disease. High turnover forms of renal osteodystrophy are characterized by rapid bone turnover caused by abnormally high PTH levels. The two types of high turnover renal osteodystrophy are predominant hyperparathyroid bone disease, and mixed uremic osteodystrophy. Low turnover forms of renal osteodystrophy are characterized by a dramatic drop in the rate of bone remodeling, caused by oversuppression of PTH and/or by aluminum accumulation. The bones become thin and overly flexible, and bowing may occur. The two types of low turnover renal osteodystrophy are low turnover uremic osteodystrophy and aluminum-related bone disease. Patients who have end-stage renal disease with increased serum phosphate levels and calciumphosphate products are associated with an increased prevalence of ectopic...

Los sedimentos de edad Cenozoico en el sur de Peru, son respuestas de una compleja interaccion de geodinamica activa y sedimentacion, de los cuales es conspicuo de la tectonica de los Andes Centrales. Mediante la combinacion de analisis multi-metodos en minerales pesados detriticos, es posible restringir la historia de levantamiento y exhumacion de los bordes de cuencas sedimentarias en el sur de Peru. Los resultados revelan que los sedimentos cenozoicos en el sur de Peru son deltas de grano grueso depositados desde hace 30 Ma, y son consecuencia de levantamientos simultaneos de la Cordillera de la Costa y la Cordillera Occidental.

The Taimyr Peninsula is a key element in the circum-Arctic region and represents thenorthern margin of the Siberian Craton. The Taimyr Peninsula is a late Paleozoic fold andthrust belt and preserves late Paleozoic through Mesozoic siliciclastic sedimentarysuccessions and providing an ideal location to investigate the Paleozoic to Mesozoictectonic evolution associated with the Uralian orogeny, the Siberian Trap magmatism andopening of Amerasia Basin within a circum-Arctic framework. Multiple methods areadopted, including petrography, heavy mineral analysis and detrital zircon U-Pbgeochronology for provenance investigation, apatite fission track dating for revealingthermal history and balanced cross section for understanding the deformation style ofTaimyr.The results of this thesis indicate that the Late Carboniferous to Permian sediments ofsouthern Taimyr were deposited in a pro-foreland basin of the Uralian orogen during theUralian orogeny. In the Triassic, the siliciclastic deposits still show a strong Uraliansignature but the initiation of Siberian Trap-related input begins to be significant. Erosionof the Uralian orogen has reached a deep metamorphic level. By Late Jurassic andCretaceous time, the deposition setting of southern Taimyr is an intracratonic basin.Erosion and input from Uralian sources waned while greater input from SiberianTrap-related rocks of the Taimyr region dominated. The Taimyr Peninsula underwent atleast three cooling and uplifting episodes: 280 Ma, 250 Ma and 220 Ma, corresponding tothe Uralian orogeny, the Siberian Traps and the late Triassic transpression. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: In press. Paper 3: Manuscript. Paper 4: Manuscript.</p>

Origin of renal osteodystrophy and cardiovascular complications are multifactorial. This complications are caused by disorders of calcium - phosphate metabolism already at the beginning of patient's irreversible renal failure. The factors playing the most important part in the development o renal ostedystrophy and are hypocalcemia and increasing serum phosphate levels associated with a declining glomerulal filtration. Two main types of renal osteodystrophy can be described - high turnover bone disease and low turnover disease. High turnover forms of renal osteodystrophy are characterized by rapid bone turnover caused by abnormally high PTH levels. The two types of high turnover renal osteodystrophy are predominant hyperparathyroid bone disease, and mixed uremic osteodystrophy. Low turnover forms of renal osteodystrophy are characterized by a dramatic drop in the rate of bone remodeling, caused by oversuppression of PTH and/or by aluminum accumulation. The bones become thin and overly flexible, and bowing may occur. The two types of low turnover renal osteodystrophy are low turnover uremic osteodystrophy and aluminum-related bone disease. Patients who have end-stage renal disease with increased serum phosphate levels and calciumphosphate products are associated with an increased prevalence of ectopic...

The focus of the current project was to establish an improved and reliable protocol for somatic embryogenesis in 1) Pinus taeda and Pinus palustris; pine species of high value for commercial applications and germplasm conservation supported through breeding programs at The Virginia Department of Forestry (Chapter III); and 2) Pinus oocarpa; an economically important pine species in the southern half of Mexico and Central America (Chapter IV). In addition, 3) the study of the gene expression analysis of developmental stages of both somatic and zygotic embryos of P. taeda was compared to assess developmental fidelity at the molecular level (Chapter V). By testing four basal media combined with different plant growth regulator combinations, we have established stable embryogenic cultures from high value families of P. taeda and P. palustris using the tissue culture medium 1218 (Pullman et al 2005) in combination with an auxin:citokinin ratio at 10:5 (molar). However, optimization of the protocols for the maturation and further conversion of somatic embryos to seedlings requires further work. For P. oocarpa, we hypothesized that somatic embryo induction may be possible by mimicking natural seed-embryo developmental conditions, and a new tissue culture medium, based on the mineral content of the seed nutritive tissue (megagametophyte), was formulated. The novel culture medium (PO) was tested in combination with different plant growth regulator concentrations for the initiation of somatic embryogenesis from fresh collections of P. oocarpa immature zygotic embryos. Additionally, the established embryogenic cultures were able to mature and germinate, to our knowledge resulting in the first report of the production of P. oocarpa plantlets through somatic embryogenesis. PO medium also has the potential to be used successfully for other tropical pine species which today suffer from suboptimal somatic embryogenesis protocols. The fundamental study of molecular regulation of embryo development showed that under the current maturation conditions, P. taeda somatic embryos were temporally similar in gene expression to zygotic embryos of the same species. However, potentially important differences were found and results could potentially explain the low germination success during somatic embryogenesis. More research is still needed to further explore the natural environment of developing seed embryos to improve the somatic embryogenesis protocols and to enable full integration of this clonal propagation method into the breeding programs for pines. / Ph. D.

No description available.

Made available in DSpace on 2016-12-08T16:44:50Z (GMT). No. of bitstreams: 1 PGPV15MA166.pdf: 4773861 bytes, checksum: 9bfc4ce3c3a8177c7734f700f76de164 (MD5) Previous issue date: 2015-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed: 1) to determine the diferences of growth rate, concentration, contente and mineral relations int in the fruit between Fuji (with low susceptibility ti bitter pit) and Catarina (with high susceptibility to bitter pit) apples; 2) to assess the mineral gradiente of Ca, Mg and K in diferente regions of Gala apples; 3) to identify the best tissue sampling method (peel and pulp) in the distal region of the fruit to quantify the concentrations of Ca and Mg in total and soluble fractions, to segregate gala apples for the occurence of bitter pit; and 4) to identify minerals and physic-chemical atributes related to the occurrence of bitter pit in Gala apples. In the first chapter, Fuji and Catarina apples were harvested in a comercial orchard in São Joaquim, SC. The fruits were harvested weekly from 40 to 131 days after full bloom (DAFB), and subsequently every 15 days up to 188 DAFB. Fruit were evaluated for fresh mass (g) and concentrations (mg kg¯¹ fw) and contentes (mg fruit¯¹) of Ca, Mg, L and N. concetrations of Ca, Mg, K and N were evaluated in the proximal, medial and distal regions of the fruit. In the second chapter, two experiments were carried out. in the first experimente, Gala apples were harvested in Fraiburgo, SC. Fruit were cut longitudinally, divided into 12 regions (nine for the pulp and three to peel), and then analyzed for concentrations of Ca, Mg and K in total and soluble fractions. In the second experimente, Gala apples were harvested in Guarapuava, PR. Fruit were dicided into lots without and with incidence of bitter pit and evaluated for physico-chemical atributes (pH, soluble solids contente, titratable acidity firmness) and Ca and Mg concentrations (in the total soluble fractions of the distal region of the fruit). In Chapter I, the results show that Catarina apple fruit has a higher growth rate than Fuji . Along the fruit growth, theaverage concentration of Ca was higher in Fuji than in Catarina the three regions: proximal, medial and distal. The highest N/Ca, (K+Mg)/Ca and (Mg+K+N)/Ca ratios occurred in Catarina at the distal region. The canonical discriminant analysis (CDA) showed that Ca concentration, regardless of the best atribute to segregte between the two cultivars. In Chapter II, experimente I, the results showed that the concentrations of Ca, Mg and K in the total fraction were higher in the skin than in the flesh, while the concentrations of theses mineral in the soluble fraction were higher in the flesh than in the skin. The total concentrations of Ca, Mg and K are lower in the córtex than in the skin. In addition, the córtex has a longitudinal gradiente, with the highest total concentrations of Ca, Mg and K in the proximal region of the fruit. The Mg/Ca, K/Ca and (K+Mg)/Ca ratios were higher in all tissues evaluated at the distal region of the fruit. In the second experimente, fruits with bitter pit had higher titratable acidity, lower pH and lower firmness, as well as high Mg/Ca ratio in the total and soluble fractions of the flesh. The ACD showed that the Mg/Ca ratio in soluble fraction of the flesh and the Mg in total fraction of the flesh for mineral atributes, and titratable acidity for the physico-chemical atributes, promoted a better segregation between fruit without and with bitter pit / Este trabalho teve por objetivos: 1) determinar as diferenças entre maçãs Fuji (com baixa suscetibilidade ao bitter pit ) e Catarina (com alta suscetibilidade ao bitter pit ) para a taxa de crescimento do fruto, concentrações, conteúdos e relações minerais; 2) determinar o gradiente mineral de Ca, Mg e K existente nas diferentes regiões em maçãs Gala ; 3) determinar qual o método de amostragem de tecidos do fruto (casca e polpa) na região distal, para quantificação das concentrações nas frações total e solúvel de Ca e Mg, mais indicado para segregar maçãs Gala quanto à ocorrência de bitter pit ; e 4) identificar atributos minerais e físico-químicos relacionados à ocorrência de bitter pit em maçãs Gala . No primeiro capítulo, utilizou-se maçãs Fuji e Catarina , provenientes de um pomar comercial do município de São Joaquim, SC. Os frutos foram colhidos semanalmente dos 40 aos 131 dias após a plena floração (DAPF), e posteriormente em intervalos de 15 dias até os 188 DAPF. Estes frutos foram avaliados quanto a massa fresca (g), concentrações (mg kg-1 massa fresca) e conteúdos (mg fruto-1) de Ca, Mg, K e N. As concentrações de Ca, Mg, K e N foram avaliadas nas regiões proximal, mediana e distal dos frutos. No segundo capítulo, foram realizados dois experimentos. No experimento I, utilizou-se maçãs Gala , provenientes do município de Fraiburgo, SC. Os frutos foram cortados longitudinalmente, separados em 12 regiões (nove para a polpa e três para casca) e analisados quanto às concentrações de Ca, Mg e K nas frações total e solúvel. No experimento II, maçãs Gala , provenientes do município de Guarapuava, PR, foram separados em lotes sem e com a incidência de bitter pit e avaliados para parâmetros físico-químicos (pH, sólidos solúveis, acidez titulável e firmeza de polpa) e minerais (Ca e Mg, nas frações total e solúvel da região distal do fruto). No primeiro capítulo, maçãs Catarina tiveram crescimento superior à Fuji . Na média dos valores avaliados ao longo do crescimento dos frutos, a concentração de Ca foi superior na Fuji nas três regiões, proximal, mediana e distal. As maiores relações N/Ca, 6 (K+Mg)/Ca e (K+Mg+N)/Ca foram encontradas para a cultivar Catarina na região distal. A análise canônica discriminante (ACD) mostrou que a concentração de Ca, independente da região do fruto, é o atributo que melhor promove segregação entre as duas cultivares. No segundo capítulo, experimento I, observou-se que as concentrações de Ca, Mg e K na fração total são superiores no tecido da casca, e na fração solúvel são maiores na polpa. As concentrações totais de Ca, Mg e K são inferiores na região do córtex. Além disto, esta região apresenta um gradiente longitudinal, onde as maiores concentrações totais de Ca, Mg e K encontram-se na região proximal dos frutos. As relações Mg/Ca, K/Ca e (K+Mg)/Ca foram superiores, em todos os tecidos avaliados, na região distal. No experimento II, frutos com bitter pit apresentaram maior acidez titulável, menor pH e menor firmeza de polpa, assim como alta relação Mg/Ca nas frações total e solúvel da polpa. A ACD indicou que a relação Mg/Ca solúvel na polpa e o Mg total na polpa para os atributos minerais, e a acidez titulável para os atributos físicoquímicos, promovem melhor segregação entre frutos sem e com bitter pit

Les laves d'arc ont une géochimie complexe du fait de l'hétérogénéité des magmas primitifs et de leur transformation dans la croûte. L'identification des magmas primitifs dans les arcs continentaux est difficile du fait de l'épaisseur de la croûte continentale, qui constitue un filtre mécanique et chimique à l'ascension des magmas. En Équateur, cette problématique est particulièrement critique du fait de la grande épaisseur de la croûte (≈ 50-60 km) et de la rareté des magmas primitifs arrivant en surface. Cette thèse a pour but de déterminer la composition des liquides primitifs dans l'arc équatorien, à l'échelle de l'arc entier, et à celle de deux édifices volcaniques : le Pichincha et le Tungurahua. Elle vise également à mieux comprendre comment ces liquides primitifs évoluent à travers la croûte continentale. En Équateur, le pendage, le relief et l'âge de la plaque plongeante varient du nord au sud de l'arc. Ainsi, la première partie de la thèse aborde la question de l'influence de ces paramètres sur la géochimie des magmas, via une étude sur roches totales couvrant la totalité de l'arc. Elle confirme les variations géochimiques décrites à travers l'arc par les études précédentes : augmentation de la teneur en éléments incompatibles et diminution de l'enrichissement en éléments "mobiles" d'est en ouest. L'étude identifie des variations géochimiques le long du front volcanique (e.g., rapport Ba/Th), liées au changement de nature des fluides métasomatiques, qui sont aqueux au centre de l'arc (environ 0,5°S) et silicatés au Nord et possiblement au Sud. Ce changement est attribué à la jeunesse du plancher océanique dans le nord de l'arc, qui pourrait promouvoir la fusion de la plaque plongeante. Enfin, il semble que la contamination par la croûte inférieure augmente vers le sud du front volcanique. Dans un deuxième temps, les produits émis par le Tungurahua lors de ses derniers 3000 ans d'activité sont étudiés. À cette échelle de temps, les paramètres tectoniques de la première étude sont constants. Ce travail détaille le rôle de la croûte dans la production des magmas différenciés, qui sont systématiquement associés à des éruptions plus explosives. Elle conclut que les andésites ont des compositions isotopiques hétérogènes (206Pb/204Pb = 18,834 - 19,038), acquises en profondeur (manteau ou croûte inférieure), qui se restreignent lors de la différenciation des andésites en dacites (206Pb/204Pb = 18,965 - 19,030), par cristallisation fractionnée et assimilation de la croûte supérieure locale (7-9 %). Enfin, la troisième partie de la thèse se focalise sur l'hétérogénéité des magmas primitifs. Des études sur minéraux individuels ont été effectuées au Pichincha et au Tungurahua, et montrent que la majorité des minéraux sont en déséquilibre avec la roche hôte (jusqu'à 8600 ppm en 206Pb/204Pb). Au Pichincha, la diversité des minéraux échantillonnés permet d'identifier la diversité des liquides mantelliques (206Pb/204Pb = 18,816 - 19,007), qui s'alignent dans les espaces Pb-Pb. Comme dans le cas des roches totales du Tungurahua, l'assimilation crustale écrase cette diversité isotopique lors de la différenciation des liquides primitifs, dont la signature n'est pas préservée dans les roches. Au Tungurahua, les minéraux individuels montrent que l'hétérogénéité des signatures est acquise en profondeur. L'analyse de deux lots d'olivines met en évidence une signature radiogénique dans les liquides primitifs du Tungurahua, interprétée comme la présence de croûte délaminée dans la source mantellique du Tungurahua. Enfin, l'étude de lots d'olivines provenant de sept volcans équatoriens montre qu'il n'existe pas de signature primitive unique dans l'arc. La totalité de l'hétérogénéité isotopique des magmas est héritée du manteau (206Pb/204Pb = 18,583 - 19,000). Les compositions des liquides primitifs sont ensuite déviées par la contamination crustale, dans la majorité des cas, vers des signatures plus radiogéniques. / Arc lavas display a complex geochemistry resulting from the heterogeneity of primitive magmas and their transformation within the crust. Identifying primitive magma compositions in continental arcs is challenging because continental crust is thick and acts as a mechanical and chemical filter for ascending magmas. This issue is particularly criticial in Ecuador owing to the great thickness of the continental crust (≈ 50-60 km) and the scarcity of erupted primitive magmas. This thesis aims to determine the composition of primitive silicate melts in the Ecuadorian arc, on the scale of the whole arc, as well as on the scale of two volcanic edifices: the Pichincha and the Tungurahua. This study also intends to better understand how those primitive melts evolve during their journey through the continental crust. In Ecuador, slab dip, relief and age change from north to south. Hence, the first part of the PhD focuses on the influence of those parameters on magma geochemistry, through a whole rock study covering the entire arc. It confirms the across-arc geochemical variations described by previous studies: an increase of incompatible element contents and a decrease of fluid-mobile over fluid-immobile element ratios from west to east. We identify along-arc geochemical variations in the volcanic front (e.g. Ba/Th), related to the changing nature of metasomatic fluids, which are aqueous fluids at the centre of the arc (around 0.5°S) and silicate melts to the north and probably to the south. This change may be due to the subduction of a younger and warmer oceanic crust to the north, which might promote slab melting. Lastly, it seems that deep crustal contamination increases towards the south of the volcanic front. Secondly, volcanic products emitted for the last 3,000 years at Tungurahua are studied. On this timescale, the tectonic parameters of the first study are constant. This work details the role of continental crust in the production of differentiated magmas, which are systematically associated with more explosive eruptions. We conclude that andesites have heterogeneous isotopic compositions (206Pb/204Pb = 18.834 - 19.038), acquired at depth (mantle or deep crust), that homogeneize through andesite differentiation to dacite (206Pb/204Pb = 18.965 - 19.030) by fractional crystallization and assimilation of the local upper crust (7-9 %). Lastly, the third part of the PhD focuses on the heterogeneity of primitive magmas. We study individual minerals from Pichincha and Tungurahua volcanoes and show that most minerals are in disequilibrium with their host rock (up to 8,600 ppm for 206Pb/204Pb). The diversity of Pichincha minerals allows the identification of mantle melt diversity (206Pb/204Pb = 18.816 - 19.007), with compositions forming a tight trend in Pb-Pb isotope spaces. As for Tungurahua whole rocks, crustal assimilation erases the diversity of primitive melt isotope signatures through differentiation, so that primitive melt signatures are not preserved in whole rock samples. At Tungurahua, individual minerals show that the heterogeneity of isotope compositions is acquired at depth. The analysis of two olivine fractions reveals the existence of a radiogenic signature in the mantle source of Tungurahua volcano, interpreted as the presence of delaminated crust within the mantle beneath its edifice. Finally, olivine fractions from seven Ecuadorian volcanoes highlight the fact that no unique primitive signature exists in the arc. Isotopic heterogeneity is entirely inherited from the mantle (206Pb/204Pb = 18.583 - 19.000). Primitive melt compositions are then shifted by continental crust contamination which, in most cases, results in more radiogenic signatures.