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Male Reproductive Apparatus and Spermatophore Morphology of the Hermit Crabs Pagurus brevidactylus and P. criniticornis (Anomura, Paguridae)

FANTUCCI, Marina Zilio; MANTELATTO, Fernando Luis
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.31%
Spermatozoa of most crustacean species are nonmotile and are packed into spermatophores. In Decapoda, spermatophores are highly variable in morphology and can be useful in the solving of taxonomic and systematic questions, especially among the Anomura. In this study, the morphology and morphometry of the spermatophores of the western Atlantic hermit crabs Pagurus brevidactylus and P criniticornis are described. The abdomen of fresh male specimens was dissected to expose the reproductive system and to extract the spermatophores, which were analyzed by stereoscopic, light, and scanning electron microscopy. The vas deferens can be divided macroscopically in three regions, all of them containing spermatophores. Tripartite spermatophores are composed of an elongated cylindrical main ampulla, a triangular accessory ampulla, a narrow cylindrical peduncle, and a round pedestal. Dimensions of the spermatophore components are positively correlated to the size of the crab. Morphological patterns observed in this study resemble those of other pagurid hermit crabs investigated to date. The morphological character distribution confirms classifications based on adult morphology and molecular analysis. J. Morphol. 272:1271-1280, 2011. (C) 2011 Wiley-Liss...

Spermatophore and Gonopore Morphology of the Southwestern-Atlantic Hermit Crab Pagurus exilis (Benedict, 1892) (Anomura, Paguridae)

SCELZO, Marcelo A.; FANTUCCI, Marina Z.; MANTELATTO, Fernando L.
Fonte: ACAD SINICA INST ZOOLOGY Publicador: ACAD SINICA INST ZOOLOGY
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.34%
Marcelo A. Scelzo, Marina Z. Fantucci, and Fernando L. Mantelatto (2010) Spermatophore and gonopore morphology of the southwestern-Atlantic hermit crab Pagurus exilis (Benedict, 1892) (Anomura, Paguridae). Zoological Studies 49(3): 421-433. The form and function of the spermatophore have been used as a complementary tool in studies of the reproductive biology and systematics of hermit crabs. In this context, we describe the spermatophore and gonopore morphology of Pagurus exilis. The spermatophores were extracted from the distal part of the vas deferens of specimens collected in Argentina and Brazil. The spermatophores were composed of 3 major regions: a main ampulla (with a sperm capsule inside and an accessory ampulla at the base), a stalk, and a pedestal. Each spermatophore had a distinct dorsolateral suture line around the ampulla, where the rupture occurs to release the sperm. The spermatophore total length was 1.5 times the main ampulla length. The main ampulla was oval and slightly flattened. A triangular accessory ampulla extended from the main ampulla base to the pedestal on 1 side, and contained no to several sperm. The stalk is short and flattened, and as wide as the main ampulla. One to 3 spermatophores were found attached to each pedestal...

Paleoamerican Morphology in the Context of European and East Asian Late Pleistocene Variation: Implications for Human Dispersion Into the New World

HUBBE, Mark; HARVATI, Katerina; NEVES, Walter
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.36%
Early American crania show a different morphological pattern from the one shared by late Native Americans. Although the origin of the diachronic morphological diversity seen on the continents is still debated, the distinct morphology of early Americans is well documented and widely dispersed. This morphology has been described extensively for South America, where larger samples are available. Here we test the hypotheses that the morphology of Early Americans results from retention of the morphological pattern of Late Pleistocene modern humans and that the occupation of the New World precedes the morphological differentiation that gave rise to recent Eurasian and American morphology. We compare Early American samples with European Upper Paleolithic skulls, the East Asian Zhoukoudian Upper Cave specimens and a series of 20 modern human reference crania. Canonical Analysis and Minimum Spanning Tree were used to assess the morphological affinities among the series, while Mantel and Dow-Cheverud tests based on Mahalanobis Squared Distances were used to test different evolutionary scenarios. Our results show strong morphological affinities among the early series irrespective of geographical origin, which together with the matrix analyses results favor the scenario of a late morphological differentiation of modern humans. We conclude that the geographic differentiation of modern human morphology is a late phenomenon that occurred after the initial settlement of the Americas. Am J Phys Anthropol 144:442-453...

Influence of a narrow depth gradient and season on the morphology, phenology, and epibiosis of the brown alga Sargassum cymosum

JACOBUCCI, G. B.; GUETH, A. Z.; TURRA, A.; LEITE, F. P. P.
Fonte: CAMBRIDGE UNIV PRESS Publicador: CAMBRIDGE UNIV PRESS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.31%
Temporal and spatial fluctuations of environmental parameters are normally assigned as causes of variations in morpho-phenological characters of seaweeds and in their epibionts, but formal tests of such hypotheses are lacking, especially in narrow gradients. The present study evaluated the influence of a very small depth gradient (1 to 3 m) and of subtle seasonality characteristic of tropical areas on morpho-phenological traits and on the occurrence of sessile epiphytic organisms using a controlled orthogonal sampling design in a sublittoral population of the tropical brown alga Sargassum cymosum. Four temporal samples were obtained over a one-year period at three depths using nine replicates. The wet weight, maximum length, number of primary and secondary branches, and proportion of secondary branches with receptacles were recorded. Epibiosis was estimated by visual evaluation of percentage cover on secondary branches. Algal morphology varied as a function of the period of the year (weaker effect) and depth (stronger effect) but in different ways for each variable analysed. In general, fronds tended to be shorter, heavier, and more ramified in shallower areas. In relation to time, the morphological characters tended mostly to present higher values in January (summer) and/or April (autumn). Frequency of receptacles did not depend on algal morphology and depth at all but varied in time...

Aspectos evolutivos da história de vida e estrutura da casca do ovo de lagartos tropiduríneos; Evolutive aspects of life history and eggshell morphology of Tropidurinae lizards

Nunes, Renata Brandt
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/08/2010 PT
Relevância na Pesquisa
36.31%
Em lagartos, componentes de história de vida apresentam grande plasticidade fenotípica e evoluem de maneira correlacionada. O número de ovos, por exemplo, tende a ser correlacionado positivamente com o tamanho corpóreo das fêmeas grávidas, tanto em linhagens evolutivas quanto entre indivíduos, embora alguns tipos de hábito pareçam restringir ninhadas maiores. Há indícios de que outros fatores, como componentes climáticos, ou latitude, também sejam determinantes das características de história de vida do grupo, tanto por questões de fisiologia termal quanto ecológicas. Componentes climáticos influenciam ainda diferentes aspectos da reprodução em lagartos, como por exemplo a estrutura e morfologia da casca dos ovos de Squamata, conforme indicam diferenças nestas características entre linhagens de lagartos ovíparos. Neste contexto, o presente trabalho investigou aspectos evolutivos da história de vida de lagartos da subfamília Tropidurinae, e sua relação com componentes climáticos e latitude, através de métodos filogenéticos comparativos. Observou-se que o número de ovos da ninhada é positivamente correlacionado com o tamanho corpóreo ao longo da linhagem dos tropiduríneos. Por outro lado, esse padrão não é observado no caso de hábito escansorial e utilização de frestas de rochas...

Partitioning the relative fitness effects of diet and trophic morphology in the threespine stickleback

Bolnick, Daniel I.; Araujo, Marcio S.
Fonte: Evolutionary Ecology Ltd Publicador: Evolutionary Ecology Ltd
Tipo: Artigo de Revista Científica Formato: 439-459
ENG
Relevância na Pesquisa
36.4%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Background: Numerous models show that if morphology and diet are correlated, frequency-dependent competition will lead to fitness differences among phenotypically dissimilar individuals within a species.Hypothesis: Selection acts primarily on diet, and only indirectly on morphology via its correlation with diet.Field sites and organism: British Columbia, Canada; 340 individual threespine stickleback (Gasterosteus aculeatus) from McNair Lake and 430 individuals from First Lake.Measurements: Stable isotopes (delta C-13 and delta N-15; a proxy for diet); trophic morphology (quantitative traits and geometric shape variables); and growth rates (RNA/DNA ratios; a proxy for the component of fitness arising from competitive or foraging ability).Analysis: Linear and quadratic regression of growth rate on stable isotopes and morphological variables to calculate the relationship between growth (a fitness proxy) and diet and/or morphology. When both morphology and isotopes affected growth rates, we used a path analysis to separate their effects.Conclusions: In the McNair Lake population, growth was dependent primarily on diet type and only indirectly on trophic morphology. In a second population...

Detection of highways in high resolution images using Mathematical Morphology techniques

Ishikawa, A. S.; Silva, E. A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
36.34%
This paper seeks to apply a routine for highways detection through the mathematical morphology tools in high resolution image. The Mathematical Morphology theory consists of describing structures geometric presents quantitatively in the image (targets or features). This explains the use of the Mathematical Morphology in this work. As high resolution images will be used, the largest difficulty in the highways detection process is the presence of trees and automobiles in the borders tracks. Like this, for the obtaining of good results through the use of morphologic tools was necessary to choose the structuring element appropriately to be used in the functions. Through the appropriate choice of the morphologic operators and structuring elements it was possible to detect the highways tracks. The linear feature detection using mathematical morphology techniques, can contribute in cartographic applications, as cartographic products updating.

Estudo do controle de tamanho e morfologia de nanopartículas de materiais inorgânicos via síntese hidrotérmica; Size and morphology control of inorganic nanoparticle by hidrothermal synthesis

Nathália Medeiros Carneiro
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/07/2012 PT
Relevância na Pesquisa
36.34%
O controle do tamanho e da morfologia dos nanomateriais abre novas perspectivas quanto a novas propriedades e sua aplicação nas mais diversas áreas como eletrônica, física e medicina. Com a redução do tamanho, a superfície dos nanomateriais passa a exercer um papel importante sobre sua reatividade. Nanomateriais de óxidos individuais de ferro, cobre, zinco, hidróxido de cobalto, hidróxido de níquel, óxidos binários, como: ferro-cobalto e ferro-níquel e hidróxido de cobalto-níquel foram sintetizados através do método hidrotérmico. A etapa de síntese inicial consistiu na síntese de óxido de ferro monitorando-se tamanho e morfologia através dos fatores: contra-íon (NO3 ou Cl), pH do meio, tempo de reação e concentração de reagentes. Foram obtidas amostras de hematita (Fe2O3) e amostras com uma mistura de hematita e goethita (FeOOH) com morfologias que variam de esferas a bastões. As curvas de magnetização apresentadas são características de materiais antiferromagnéticos e ferromagnéticos fracos. A mesma síntese com variação apenas do fator contra-íon foi aplicada a níquel e cobalto, levando a formação dos hidróxidos correspondentes na forma de placas hexagonais. A mesma síntese aplicada a cobre resulta na mistura dos óxidos CuO e Cu2O na forma de placas...

Influence of a narrow depth gradient and season on the morphology, phenology, and epibiosis of the brown alga Sargassum cymosum

JACOBUCCI, G. B.; GUETH, A. Z.; TURRA, A.; LEITE, F. P. P.
Fonte: CAMBRIDGE UNIV PRESS Publicador: CAMBRIDGE UNIV PRESS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.31%
Temporal and spatial fluctuations of environmental parameters are normally assigned as causes of variations in morpho-phenological characters of seaweeds and in their epibionts, but formal tests of such hypotheses are lacking, especially in narrow gradients. The present study evaluated the influence of a very small depth gradient (1 to 3 m) and of subtle seasonality characteristic of tropical areas on morpho-phenological traits and on the occurrence of sessile epiphytic organisms using a controlled orthogonal sampling design in a sublittoral population of the tropical brown alga Sargassum cymosum. Four temporal samples were obtained over a one-year period at three depths using nine replicates. The wet weight, maximum length, number of primary and secondary branches, and proportion of secondary branches with receptacles were recorded. Epibiosis was estimated by visual evaluation of percentage cover on secondary branches. Algal morphology varied as a function of the period of the year (weaker effect) and depth (stronger effect) but in different ways for each variable analysed. In general, fronds tended to be shorter, heavier, and more ramified in shallower areas. In relation to time, the morphological characters tended mostly to present higher values in January (summer) and/or April (autumn). Frequency of receptacles did not depend on algal morphology and depth at all but varied in time...

Relationships between dendritic morphology, spatial distribution and firing patterns in rat layer 1 neurons

Santos,D.V.V.; Costa,K.M.; Vaz,M.C.G.; Silva Filho,M. Da
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
36.34%
The cortical layer 1 contains mainly small interneurons, which have traditionally been classified according to their axonal morphology. The dendritic morphology of these cells, however, has received little attention and remains ill defined. Very little is known about how the dendritic morphology and spatial distribution of these cells may relate to functional neuronal properties. We used biocytin labeling and whole cell patch clamp recordings, associated with digital reconstruction and quantitative morphological analysis, to assess correlations between dendritic morphology, spatial distribution and membrane properties of rat layer 1 neurons. A total of 106 cells were recorded, labeled and subjected to morphological analysis. Based on the quantitative patterns of their dendritic arbor, cells were divided into four major morphotypes: horizontal, radial, ascendant, and descendant cells. Descendant cells exhibited a highly distinct spatial distribution in relation to other morphotypes, suggesting that they may have a distinct function in these cortical circuits. A significant difference was also found in the distribution of firing patterns between each morphotype and between the neuronal populations of each sublayer. Passive membrane properties were...

The inter-relationship between inoculum concentration, morphology, rheology and erythromycin productivity in submerged cultivation of Saccharopolyspora erythraea

Ghojavand,H.; Bonakdarpour,B.; Heydarian,S. M.; Hamedi,J.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
36.34%
Submerged cultivation of Saccharopolyspora erythraea, at different initial spore concentrations, was carried out to study the inter-relationship between inoculum concentration, morphology, rheology and erythromycin production. Pellet morphology was dominant in runs at 10³ and 10(4) spore/ml initial spore concentrations, whereas there was a significant presence of clump morphology in runs at initial spore concentrations of 10(5)-10(7) spore/ml. The S. erythraea cultivation broths exhibited Newtonian rheology in runs at initial spore concentrations of 10³ and 10(4) spore/ml, whereas at higher initial spore concentrations the rheological data could be fitted with the power law model. Runs in which clump morphology was predominant resulted in the highest erythromycin productivities. The findings of the present work suggest that the predominance of clump morphology, smaller sized clumps and, in the case of non-Newtonian S. erythraea cultivation broths, a decrease in viscosity enhance erythromycin production.

Clay nanoparticles effects on performance and morphology of poly(vinylidene fluoride) membranes

Morihama,A. C. D.; Mierzwa,J. C.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 EN
Relevância na Pesquisa
36.34%
In this study, a comparison between neat poly(vinylidene fluoride) (PVDF) membrane and composite (PVDF-Nanoclay and PVDF-PVP-Nanoclay) membranes is presented. All membranes were synthesized by the phase inversion process, using 18% PVDF, n-methylpyrrolidone as solvent and water as the non-solvent. Demineralized water cross-flow permeation tests were conducted to evaluate the membranes performance. Scanning electron microscopy (SEM) images of the membranes surface and cross-section and water contact angle measurements were used to estimate additives effects on membranes morphology. The results indicate that dopant addition affected membrane permeate flux and morphology. The 4% nanoclay composite membrane resulted in the highest ultrapure water permeability (0.9130 m³.m-2.h-1.MPa-1), lower hydraulic resistance (3.27´10+12.m-1), lower contact angle (87.1º) and highest surface porosity (0.95%). Furthermore, it was verified that the membrane surface porosity increased with increasing clay nanoparticles concentrations. It was observed that the morphology of the membranes with clay nanoparticle addition is characterized by a thin surface layer, with macro-pores, a thin bottom layer, which has a sponge-like structure with micro-pores and a thick intermediate layer...

An analysis of meander bend morphology in the tidal-fluvial transition zone

Eastwood, Jack V. L.
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
36.41%
Previous qualitative work had shown that a straight–meandering–straight morphology exists within the tidal-fluvial transition zone of estuarine systems, whereas delta systems exhibit a progressive straightening towards the river mouth. The present study sought to determine if the straight–meandering–straight zone was, in fact, a unique trait of estuarine channels. Additionally the study determined if the straight-meandering-straight morphology had a predictable meander shape and location within the tidal-fluvial transition zone. 17 estuarine channels and 19 deltaic channels with moderate to significant tidal influence were analysed for the study. The sinuosity index, radius of curvature, meander shape, and meander skewness for each channel bend were determined using high resolution satellite imagery (NASA Landsat 7, Google Earth). Quantitative measurements were obtained using Universal Desktop Ruler v.2.5 software. Results were plotted against distance, expressed as a normalized percent of the total length of the tidal-fluvial transition, to allow comparisons between systems with vastly different dimensions. Seven estuarine channels showed the straight-meandering-straight morphology or a variation on it. 13 deltaic channels did not show the straight–meandering–straight morphology...

Systematic and palaeobiological implications of postcranial morphology in the Diprotodontidae (Marsupialia).

Camens, Aaron B.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2010
Relevância na Pesquisa
36.38%
This thesis is focused on the information that can be gained from examining diprotodontid forelimb and hindlimb anatomy in a morphological, functional, palaeobiological, and phylogenetic context. This research is complemented through a study of diprotodontid fossil trackways, allowing testing of the hypotheses developed through study of skeletal anatomy, as well as providing insights into the palaeobiology of taxa that are not evident through study of skeletal anatomy. The discovery of an articulated hindlimb of Euowenia grata, from the Warburton River, allowed an investigation of the functional capabilities of this taxon (Chapter 2). It is shown that the development of the graviportal limb morphology exemplified by Diprotodon optatum was already well underway during the early Pliocene in E. grata. It is also suggested that the hindlimb morphology of E. grata is indicative of the ability to rear up against trees. In addition, the pedal digits of Pliocene diprotodontines demonstrate a similar degree of reduction to that seen later Pleistocene taxa such as D. optatum. Pliocene trackways from the Warburton River in central Australia, representing the oldest known Australian mammal trackways, are described in Chapter 3. The track-maker is identified as Euowenia grata...

The effect of lunate morphology on the 3-dimensional kinematics of the carpus

Bain, G.I.; Clitherow, H.D.S.; Millar, S.; Fraysse, F.; Costi, J.J.; Eng, K.; McGuire, D.T.; Thewlis, D.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
36.34%
PURPOSE: To assess carpal kinematics in various ranges of motion in 3 dimensions with respect to lunate morphology. METHODS: Eight cadaveric wrists (4 type I lunates, 4 type II lunates) were mounted into a customized platform that allowed controlled motion with 6 degrees of freedom. The wrists were moved through flexion-extension (15°-15°) and radioulnar deviation (RUD; 20°-20°). The relative motion of the radius, carpus, and third metacarpal were recorded using optical motion capture methods. RESULTS: Clear patterns of carpal motion were identified. Significantly greater motion occurred at the radiocarpal joint during flexion-extension of type I wrist than a type II wrist. The relative contributions of the midcarpal and radiocarpal articulations to movement of the wrist differed between the radial, the central, and the ulnar columns. During wrist flexion and extension, these contributions were determined by the lunate morphology, whereas during RUD, they were determined by the direction of wrist motion. The midcarpal articulations were relatively restricted during flexion and extension of a type II wrist. However, during RUD, the midcarpal joint of the central column became the dominant articulation. CONCLUSIONS: This study describes the effect of lunate morphology on 3-dimensional carpal kinematics during wrist flexion and extension. Despite the limited size of the motion arcs tested...

Tailoring vessel morphology in vivo

Gould, Daniel Joseph
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
36.4%
Tissue engineering is a rapidly growing field which seeks to provide alternatives to organ transplantation in order to address the increasing need for transplantable tissues. One huge hurdle in this effort is the provision of thick tissues; this hurdle exists because currently there is no way to provide prevascularized or rapidly vascularizable scaffolds. To design thick, vascularized tissues, scaffolds are needed that can induce vessels which are similar to the microvasculature found in normal tissues. Angiogenic biomaterials are being developed to provide useful scaffolds to address this problem. In this thesis angiogenic and cell signaling and adhesion factors were incorporated into a biomimetic poly(ethylene glycol) (PEG) hydrogel system. The composition of these hydrogels was precisely tuned to induce the formation of differing vessel morphology. To sensitively measure induced microvascular morphology and to compare it to native microvessels in several tissues, this thesis developed an image-based tool for quantification of scale invariant and classical measures of vessel morphology. The tool displayed great utility in the comparison of native vessels and remodeling vessels in normal tissues. To utilize this tool to tune the vessel response in vivo ...

Characterization of the dental morphology of a Portuguese sample from the 19th and 20th centuries

Moreira, Luís Miguel do Carmo Rocha Marado
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
36.36%
A morfologia dentária analisa um conjunto de caracteres vastamente estudados cuja variação é determinada maioritariamente por diversidade genética. Essa variação, expressa nas frequências dos traços em cada amostra, difere entre populações em abrangentes escalas geográficas. Deste modo permite que as relações biológicas entre amostras sejam calculadas estatisticamente. O Arizona State University Dental Anthropology System (ASUDAS) e outros métodos complementares foram usados para registar a morfologia dentária e oral de 600 indivíduos identificados (300 de cada sexo), de duas coleções (Trocas Internacionais e Escolas Médicas) da Universidade de Coimbra, que pereceram em Portugal nos finais do século XIX, e inícios a meados do século XX. Estas frequências da morfologia dentária foram analisadas e comparadas com outras de diversos autores, com o objetivo de inferir as relações biológicas com outras amostras e os efeitos do fluxo génico em Portugal ao longo do tempo. As consequências de outros fatores na morfologia dentária da amostra e no seu registo também foram analisadas. Análise de componentes principais, tau-b de Kendall, rho de Spearman, chi quadrado de Pearson, H de Kruskall-Wallis, U de Mann-Whitney e Z-ratio foram os testes estatísticos usados. A precisão média (precisão geral: 89.4%; precisão com margem de um grau: 96.0%; precisão na presença/ausência: 94.5%) no registo dos caracteres não-métricos dentários foi adequada. Apenas o tuberculum dentale apresentou pouca fiabilidade na repetição...

Patterns of association between canopy-morphology and understorey assemblages across temperate Australia

Fowler-Walker, M.; Gillanders, B.; Connell, S.; Irving, A.
Fonte: Academic Press Ltd Elsevier Science Ltd Publicador: Academic Press Ltd Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
36.34%
Patterns of association between canopy and understorey vegetation have been described over 1000s of km according to the presence and absence of algal canopies and the different types of canopies. However, the degree to which morphological variation of the canopy is correlated with patterns in the understorey algal assemblage is unknown. We tested the hypothesis that variation in the morphology of Ecklonia radiata, growing in monospecific canopies, is associated with variation in the structure of understorey assemblages at regional scales across temperate Australia. We found that the morphology of kelp did correlate with the structure of understorey assemblages, over broad spatial scales, particularly that of surface area/volume ratio and measures of stipe width. These canopy-understorey associations revealed two ‘types’ of kelp forest; one characteristic of Western and South Australia and the other of Eastern Australia. We suggest that future research on causal relationships between morphology and understorey assemblages of algae consider the potential importance that morphology may have on mechanisms such as light penetration and physical abrasion by fronds. Whilst correlations between the understorey and morphology do not demonstrate causality...

Tailoring fungal morphology of Aspergillus niger MYA 135 by altering the hyphal morphology and the conidia adhesion capacity: biotechnological applications

Colin, Veronica Leticia; Baigori, Mario Domingo; Pera, Licia Maria
Fonte: Springer Publicador: Springer
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
Relevância na Pesquisa
36.38%
Current problems of filamentous fungi fermentations and their further successful developments as microbial cell factories are dependent on control fungal morphology. In this connection, this work explored new experimental procedures in order to quantitatively check the potential of some culture conditions to induce a determined fungal morphology by altering both hyphal morphology and conidia adhesion capacity. The capacity of environmental conditions to modify hyphal morphology was evaluated by examining the influence of some culture conditions on the cell wall lytic potential of Aspergillus niger MYA 135. The relative value of the cell wall lytic potential was determined by measuring a cell wall lytic enzyme activity such as the mycelium-bound β-N-acetyl-Dglucosaminidase (Mb-NAGase). On the other hand, the quantitative value of conidia adhesion was considered as an index of its aggregation capacity. Concerning microscopic morphology, a highly negative correlation between the hyphal growth unit length (lHGU) and the specific Mb-NAGase activity was found (r = −0.915, P < 0.001). In fact, the environment was able to induce highly branched mycelia only under those culture conditions compatible with specific Mb-NAGase values equal to or higher than 190 U gdry.wt -1. Concerning macroscopic morphology...

Morphology of arbuscular mycorrhizas in Tabebuia avellanedae Lorentz ex Griseb. (Bignoniaceae); Morfologia de micorrizas arbusculares em Tabebuia avellanedae Lorentz ex Griseb. (Bignoniaceae)

Paulilo, Maria Terezinha Silveira; Universidade Federal de Santa Catarina; Moratelli, Eliane Maria; Universidade Federal de Santa Catarina; Dalla Costa, Murilo; Universidade Federal de Santa Catarina; Santos, Marisa; Universidade Federal de Santa Catarina
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; substrato de cultivo inoculado.; Substratum inoculated. Formato: application/pdf
Publicado em 01/01/2007 POR
Relevância na Pesquisa
36.36%
O conhecimento sobre o tipo de morfologia de micorrizas arbusculares é importante uma vez que a função fisiológica das estruturas micorrízicas e reações de defesa do hospedeiro podem apresentar diferenças entre as morfologias Arum e Paris. As raízes de plântulas de Tabebuia avellanedae, colonizadas tanto por população nativa presente no solo de mata utilizado no cultivo ou provindos de inoculação do solo de mata com Glomus clarum e Glomus tunicatum, apresentaram micorrizas arbusculares tanto com morfologia tipo Arum como morfologia tipo Paris, caracterizando uma morfologia do tipo intermediário. A presença de morfologia intermediária poderia ser ecologicamente vantajosa, pois traria aos hospedeiros os benefícios apresentados pelas morfologias Arum e Paris.; The knowledge about de morphology of arbuscular mycorrhizas is important since the physiological function of mycorrhizal structure and defense reactions of host can show differences between the Arum and Paris type morphology. Root seedlings of Tabebuia avellanedae, colonized both by native or inoculated (Glomus clarum and Glomus tunicatum) arbuscular mycorrhizal fungi showed both Arum and Paris type of morphology, characterizing an interrnediary type of morphology. This kind of morphology can bring ecological important since the hosts could take benefit of the advantages of each type of morphology.