973 resultados para Howard Phillips Lovecraft


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Native from south eastern Australia, Eucalyptus globulus is the main species in eucalypts plantations in Portugal. The most serious foliar disease in eucalypt plantations is linked to Mycosphaerella senso lato, which affects young trees in the juvenile phase foliage causing leaf necrosis. This disease results in reduced growth rate of the host and lower wood volume, thus causing significant productivity losses. The most common name for this disease was Mycosphaerella Leaf Disease that became inappropriate when most of the pathogens on eucalypts were re-distributed into several genera. The term "Eucalyptus Leaf Disease Complex" is now more appropriate. The overall aim of this thesis was to investigate the Eucalyptus Leaf Disease Complex in Portugal, focusing on species diversity, taxonomy and the role played by each species in the disease complex on Eucalyptus globulus. Literature on the Eucalyptus Leaf Disease Complex was reviewed and the species were distributed into several genera. A survey based on symptomatic leaves collected from several Eucalyptus globulus plantations and characterized by morphological and molecular tools provided an overview of species incidence and of the most frequent species in the disease complex. The present work reveals additional species of Mycosphaerella senso lato associated with eucalypt plantations in Portugal. Thus, five new records of Teratosphaeria and phylogenetically related species were added to the Iberian Peninsula, namely, Neodevriesia hilliana, for the first time on Myrtaceae; Quasiteratosphaeria mexicana, Teratosphaericola pseudoafricana, Teratosphaeria pluritubularis and Teratosphaeria lusitanica, a new species. Furthermore, new anamorphic structures were found and two new combinations were made. Regarding other genera, some species were observed for the first time, such as Cladosporium cladosporioides, Fusicladium eucalypti, Mycosphaerella madeirae, in the mainland. In addition to leave diseases, Teratosphaeria gauchensis was found causing a severe stem and trunk canker on Eucalyptus globulus. The aggressiveness of several species was compared to evaluate each species individually in the complex, permitting to distinguish different behaviours, from primary to secondary pathogens. Cladosporium cladosporioides, M. communis and M. lateralis, appeared to be more aggressive than Teratosphaeria nubilosa. In fact, contrary to the prevailing views on this disease complex, Teratosphaeria nubilosa is not the only species responsible for the disease, which clearly involves a complex of species acting together.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tissue-to-tissue interfaces are commonly present in all tissues exhibiting structural, biological and chemical gradients serving a wide range of physiological functions. These interfaces are responsible for mediation of load transfer between two adjacent tissues. They are also important structures in sustaining the cellular communications to retain tissueâ s functional integration and homeostasis. [1] All cells have the capacity to sense and respond to physical and chemical stimulus and when cultured in three-dimensional (3D) environments they tend to perform their function better than in two-dimensional (2D) environments. Spatial and temporal 3D gradient hydrogels better resemble the natural environment of cells in mimicking their extracellular matrix. [2] In this study we hypothesize that differential functional properties can be engineered by modulation of macromolecule gradients in a cell seeded threedimensional hydrogel system. Specifically, differential paracrine secretory profiles can be engineered using human Bone Marrow Stem Cells (hBMSCâ s). Hence, the specific objectives of this study are to: assemble the macromolecular gradient hydrogels to evaluate the suitablity for hBMSCâ s encapsulation by cellular viability and biofunctionality by assessing the paracrine secretion of hBMSCâ s over time. The gradient hydrogels solutions were prepared by blend of macromolecules in one solution such as hyaluronic (HA) acid and collagen (Col) at different ratios. The gradient hydrogels were fabricated into cylindrical silicon moulds with higher ratio solutions assembled at the bottom of the mould and adding the two solutions consecutively on top of each other. The labelling of the macromolecules was performed to confirm the gradient through fluorescence microscopy. Additionally, AFM was conducted to assess the gradient hydrogels stiffness. Gradient hydrogels characterization was performed by HA and Col degradation assay, degree of crosslinking and stability. hBMSCâ s at P3 were encapsulated into each batch solution at 106 cells/ml solution and gradient hydrogels were produced as previously described. The hBMSCâ s were observed under confocal microscopy to assess viability by Live/Dead® staining. Cellular behaviour concerning proliferation and matrix deposition was also performed. Secretory cytokine measurement for pro-inflammatory and angiogenesis factors was carried out using ELISA. At genomic level, qPCR was carried out. The 3D gradient hydrogels platform made of different macromolecules showed to be a suitable environment for hBMSCâ s. The hBMSCâ s gradient hydrogels supported high cell survival and exhibited biofunctionality. Besides, the 3D gradient hydrogels demonstrated differentially secretion of pro-inflammatory and angiogenic factors by the encapsulated hBMSCâ s. References: 1. Mikos, AG. et al., Engineering complex tissues. Tissue Engineering 12,3307, 2006 2. Phillips, JE. et al., Proc Natl Acad Sci USA, 26:12170-5, 2008

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O gênero Coccoloba está representado na Amazônia brasileira por 23 espécies: Coccoloba acuminata Kunth, C. arborescens (Vell.) R. A. Howard, C. ascendens Duss ex Lindau, C. brasiliensis Nees & Mart., C. charitostachya Standl., C. conduplicata Maguire, C. coronata Jacq., C. declinata (Vell.) Mart., C. densifrons Mart. ex Meisn., C. excelsa Benth., C. gentryi R. A. Howard, C. latifolia Lam., C. lehmannii Lindau, C. lucidula Benth., C. marginata Benth., C. mollis Casar., C. ovata Benth., C. paraensis Meisn., C. parimensis Benth., C. ramosissima Wedd., C. savannarum Standl., C. striata Benth. e C. tenuiflora Lindau, dentre as quais apenas C. paraensis ocorre exclusivamente na Amazônia brasileira, C. charitostachya, C. conduplicata, C. coronata, C. gentryi, C. lehmanni e C. savannarum, são citadas pela primeira vez para o Brasil. As características de maior relevância taxonômica são a posição do pecíolo em relação à ócrea, ramificação da inflorescência, tamanhos relativos das brácteas e ocréolas, perianto frutífero e pericarpo. São apresentadas chaves de identificação, descrições e ilustrações, bem como comentários sobre a distribuição geográfica, hábitats e dados fenológicos para todas as espécies estudadas.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

[Excerto] Há quem advogue que a publicidade pode ser encarada como um sismógrafo (Sodré, 2006) ou um espelho da sociedade (Foz, 1984). Ambas as metáforas pecam por mecanicismo e univocidade. A publicidade abala tanto quanto é abalada e servir de espelho não é a sua vocação actual. Ela declina retratar tanto o produto como o público, público que, por sua vez, dispensa rever-se na publicidade. Procura, antes pelo contrário, a sensação de espanto e o sentimento de estranheza. Muita da publicidade actual, quiçá a melhor, não imita, mas alucina, não argumenta, mas seduz, nem sequer insinua, insinua-se, através da pele e dos sentidos (Kherckove, 1997). Esta dinâmica não se reduz a dois lados com o seu pêndulo de ecos e reflexos. A actividade publicitária não decorre de uma agência isolada que produz efeitos externos. Parte específica de um todo, integra uma configuração que convoca a sociedade, a cultura e a vida quotidiana (Lears, 1994).A actividade publicitária constitui um“mundo”, no sentido de Howard S. Becker (1988), ou um“campo”, no sentido de Pierre Bourdieu (1976; 1984; 1992). À semelhança da ciência e da arte, a actividade publicitária logrou alguma autonomia, que, por ser mais recente, não é menos complexa. Alberga sistemas de posições e disposições, recursos e percursos, regras e enredos, cooperação e conflito, legitimidades e instâncias de reconhecimento.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Identidades digitais: Howard Reingold; Comunidades virtuais; Desencarnação (desimbodiment); Sherry Turkle; Papéis sociais virtuais. O second self e o efeito Pessoa. Identidade no ciberespaço: Projeto 1: Identidade social virtual; Projeto 2: Digitalização da existência / experiência social; Projeto 3: Fetichização do consumo digital; Projeto 4: O cidadão enredado. Katherine Hayles: pós-humano. Subjetividade e identidade. Tecnologias da transcendência corporal. Projeto 5: Perfis de utilizadores e tipos de redes sociais. Projeto 6: Nuvens Semânticas na Blogosfera. Projeto 7: Dados pessoais e diferença social. Projeto 8: Identidade e privacidade. Projeto 9: Bancos de dados e bancos da alta finança . Projeto 10: Segurança e identidade democrática.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dissertação de mestrado em Comunicação, Arte e Cultura