999 resultados para Harbor structures


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The necessity of the insertion of the capital of Rio Grande do Norte in the world-wide commercial scene and its claim as the seat of political power, in ends of nineteenth and beginning of twentieth century, determined the direction of urban interventions undertaken by government to restructure the city. In that matter, there were several actions of improvements and embellishment in Natal, which had, as a starting point, the adequacy works of the port, located in the Ribeira quarter, with the aim of ending the physical isolation that reinforced its economic stagnation. Besides the problems faced in the opening bar of the Potengi River, and would complement the required improvements, other barriers demonstrate the tension established between the physic-geographic field and the man: the flooded and slope which connected Cidade Alta and Ribeira the first two quarters of the city.The execution of these works demanded knowledge whose domain and application it was for engineering. But, how the actions done for the engineers, in sense to transform natural areas into constructed spaces made possible the intentional conformation of the quarter of the Ribeira in a commercial and politician-administrative center, in the middle of the XIX century and beginning of the XX? Understand, therefore, the employment effects of technology on the physical-geographical Ribeira, is the objective of this work that uses theoretical and methodological procedures of Urban Environmental History, by analyzing the relationship between the environment and the man, mediated by knowledge and use of technologies. The documental research was used, as primary sources, the Messages of the Provincial Assembly Government that later became the Legislative Assembly of Rio Grande do Norte reports and articles on specialized publications, in addition to local newspapers. The work is structured in five chapters. First, some comments about Urban Environmental History (Chapter 1) supplemented with analysis of the conceptual construction of nature in the Contemporary Era and its application in the city (chapter 02), the following chapters (03 and 04) deal with the rise of engineers as a active group in the Brazilian government frameworks and their vision about the nature inside the urban environment and it is studied how the professional technicians dealt with the improvement work of the harbor and in the shock with the natural forces. Other works that would complement this "project" of modernization and had had natural obstacles to be removed the Ribeira flood and slope constitute the subject of the fifth chapter. Finally, some final considerations retake the initial discussions aiming an association between the technique and the nature as junction elements inside the process of constitution of a Modern Natal

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[EN] Sediment materials play an important role on the dynamic response of large structures where fluid-soil-structure interaction is relevant and materials of that kind are present. Dam-reservoir systems and harbor structures are examples of civil engineering constructions where those effects are significant.

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The necessity of the insertion of the capital of Rio Grande do Norte in the world-wide commercial scene and its claim as the seat of political power, in ends of nineteenth and beginning of twentieth century, determined the direction of urban interventions undertaken by government to restructure the city. In that matter, there were several actions of improvements and embellishment in Natal, which had, as a starting point, the adequacy works of the port, located in the Ribeira quarter, with the aim of ending the physical isolation that reinforced its economic stagnation. Besides the problems faced in the opening bar of the Potengi River, and would complement the required improvements, other barriers demonstrate the tension established between the physic-geographic field and the man: the flooded and slope which connected Cidade Alta and Ribeira the first two quarters of the city.The execution of these works demanded knowledge whose domain and application it was for engineering. But, how the actions done for the engineers, in sense to transform natural areas into constructed spaces made possible the intentional conformation of the quarter of the Ribeira in a commercial and politician-administrative center, in the middle of the XIX century and beginning of the XX? Understand, therefore, the employment effects of technology on the physical-geographical Ribeira, is the objective of this work that uses theoretical and methodological procedures of Urban Environmental History, by analyzing the relationship between the environment and the man, mediated by knowledge and use of technologies. The documental research was used, as primary sources, the Messages of the Provincial Assembly Government that later became the Legislative Assembly of Rio Grande do Norte reports and articles on specialized publications, in addition to local newspapers. The work is structured in five chapters. First, some comments about Urban Environmental History (Chapter 1) supplemented with analysis of the conceptual construction of nature in the Contemporary Era and its application in the city (chapter 02), the following chapters (03 and 04) deal with the rise of engineers as a active group in the Brazilian government frameworks and their vision about the nature inside the urban environment and it is studied how the professional technicians dealt with the improvement work of the harbor and in the shock with the natural forces. Other works that would complement this "project" of modernization and had had natural obstacles to be removed the Ribeira flood and slope constitute the subject of the fifth chapter. Finally, some final considerations retake the initial discussions aiming an association between the technique and the nature as junction elements inside the process of constitution of a Modern Natal

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The necessity of the insertion of the capital of Rio Grande do Norte in the world-wide commercial scene and its claim as the seat of political power, in ends of nineteenth and beginning of twentieth century, determined the direction of urban interventions undertaken by government to restructure the city. In that matter, there were several actions of improvements and embellishment in Natal, which had, as a starting point, the adequacy works of the port, located in the Ribeira quarter, with the aim of ending the physical isolation that reinforced its economic stagnation. Besides the problems faced in the opening bar of the Potengi River, and would complement the required improvements, other barriers demonstrate the tension established between the physic-geographic field and the man: the flooded and slope which connected Cidade Alta and Ribeira the first two quarters of the city.The execution of these works demanded knowledge whose domain and application it was for engineering. But, how the actions done for the engineers, in sense to transform natural areas into constructed spaces made possible the intentional conformation of the quarter of the Ribeira in a commercial and politician-administrative center, in the middle of the XIX century and beginning of the XX? Understand, therefore, the employment effects of technology on the physical-geographical Ribeira, is the objective of this work that uses theoretical and methodological procedures of Urban Environmental History, by analyzing the relationship between the environment and the man, mediated by knowledge and use of technologies. The documental research was used, as primary sources, the Messages of the Provincial Assembly Government that later became the Legislative Assembly of Rio Grande do Norte reports and articles on specialized publications, in addition to local newspapers. The work is structured in five chapters. First, some comments about Urban Environmental History (Chapter 1) supplemented with analysis of the conceptual construction of nature in the Contemporary Era and its application in the city (chapter 02), the following chapters (03 and 04) deal with the rise of engineers as a active group in the Brazilian government frameworks and their vision about the nature inside the urban environment and it is studied how the professional technicians dealt with the improvement work of the harbor and in the shock with the natural forces. Other works that would complement this "project" of modernization and had had natural obstacles to be removed the Ribeira flood and slope constitute the subject of the fifth chapter. Finally, some final considerations retake the initial discussions aiming an association between the technique and the nature as junction elements inside the process of constitution of a Modern Natal

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The increase in harbor seal (Phoca vitulina richardsi) abundance, concurrent with the decrease in salmonid (Oncorhynchus spp.) and other fish stocks, raises concerns about the potential negative impact of seals on fish populations. Although harbor seals are found in rivers and estuaries, their presence is not necessarily indicative of exclusive or predominant feeding in these systems. We examined the diet of harbor seals in the Umpqua River, Oregon, during 1997 and 1998 to indirectly assess whether or not they were feeding in the river. Fish otoliths and other skeletal structures were recovered from 651 scats and used to identify seal prey. The use of all diagnostic prey structures, rather than just otoliths, increased our estimates of the number of taxa, the minimum number of individuals and percent frequency of occurrence (%FO) of prey consumed. The %FO indicated that the most common prey were pleuronectids, Pacific hake (Merluccius productus), Pacific stag-horn sculpin (Leptocottus armatus), osmerids, and shiner surfperch (Cymatogaster aggregata). The majority (76%) of prey were fish that inhabit marine waters exclusively and fish found in marine and estuarine areas (e.g. anadromous spp.) which would indicate that seals forage predominantly at sea and use the estuary for resting and opportunistic feeding. Salmonid remains were encountered in 39 samples (6%); two samples contained identifiable otoliths, which were determined to be from chi-nook salmon (O. tshawytscha). Because of the complex salmonid composition in the Umpqua River, we used molecular genetic techniques on salmonid bones retrieved from scat to discern species that were rare from those that were abundant. Of the 37 scats with salmonid bones but no otoliths, bones were identified genetically as chinook or coho (O. kisutch) salmon, or steelhead trout (O. mykiss) in 90% of the samples.

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Marine mammal diet is typically characterized by identifying fish otoliths and cephalopod beaks retrieved from stomachs and fecal material (scats). The use and applicability of these techniques has been the matter of some debate given inherent biases associated with the method. Recent attempts to identify prey using skeletal remains in addition to beaks and otoliths are an improvement; however, difficulties incorporating these data into quantitative analyses have limited results for descriptive analyses such as frequency of occurrence. We attempted to characterize harbor seal (Phoca vitulina) diet in an area where seals co-occur with several salmon species, some endangered and all managed by state or federal agencies, or both. Although diet was extremely variable within sampling date, season, year, and between years, the frequency and number of individual prey were at least two times greater for most taxa when prey structures in addition to otoliths were identified. Estimating prey mass in addition to frequency and number resulted in an extremely different relative importance of prey in harbor seal diet. These data analyses are a necessary step in generating estimates of the size, total number, and annual biomass of a prey species eaten by pinnipeds for inclusion in fisheries management plans.

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Diversity of particle-attached and free-living marine bacteria in Victoria Harbor, Hong Kong, and its adjacent coastal and estuarial environments was investigated using DNA fingerprinting and clone library analysis. Denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA genes showed that bacterial communities in three stations of Victoria Harbor were similar, but differed from those in adjacent coastal and estuarine stations. Particle-attached and free-living bacterial community composition differed in the Victoria Harbor area. DNA sequencing of 28 bands from DGGE gel showed Alphaproteobacteria was the most abundant group, followed by the Bacteroidetes, and other Proteobacteria. Bacterial species richness (number of DGGE bands) differed among stations and populations (particle-attached and free-living; bottom and surface). BIOENV analysis indicated that the concentrations of suspended solids were the major contributing parameter for the spatial variation of total bacterial community structure. Samples from representative stations were selected for clone library (548 clones) construction and their phylogenetic distributions were similar to those of sequences from DGGE. Approximately 80% of clones were affiliated to Proteobacteria, Bacteroidetes and Cyanobacteria. The possible influences of dynamic pollution and hydrological conditions in the Victoria Harbor area on the particle-attached and free-living bacterial community structures were discussed.

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Diversity of particle-attached and free-living marine bacteria in Victoria Harbor, Hong Kong, and its adjacent coastal and estuarial environments was investigated using DNA fingerprinting and clone library analysis. Denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA genes showed that bacterial communities in three stations of Victoria Harbor were similar, but differed from those in adjacent coastal and estuarine stations. Particle-attached and free-living bacterial community composition differed in the Victoria Harbor area. DNA sequencing of 28 bands from DGGE gel showed Alphaproteobacteria was the most abundant group, followed by the Bacteroidetes, and other Proteobacteria. Bacterial species richness (number of DGGE bands) differed among stations and populations (particle-attached and free-living; bottom and surface). BIOENV analysis indicated that the concentrations of suspended solids were the major contributing parameter for the spatial variation of total bacterial community structure. Samples from representative stations were selected for clone library (548 clones) construction and their phylogenetic distributions were similar to those of sequences from DGGE. Approximately 80% of clones were affiliated to Proteobacteria, Bacteroidetes and Cyanobacteria. The possible influences of dynamic pollution and hydrological conditions in the Victoria Harbor area on the particle-attached and free-living bacterial community structures were discussed.

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Mode of access: Internet.

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The fusion of a protein of interest to a large-affinity tag, such as the maltose-binding protein (MBP), thioredoxin (TRX), or glutathione-S-transferase (GST), can be advantageous in terms of increased expression, enhanced solubility, protection from proteolysis, improved folding, and protein purification via affinity chromatography. Unfortunately, crystal growth is hindered by the conformational heterogeneity induced by the fusion tag, requiring that the tag is removed by a potentially problematic cleavage step. The first three crystal structures of fusion proteins with large-affinity tags have been reported recently. All three structures used a novel strategy to rigidly fuse the protein of interest to MBP via a short three- to five-amino acid spacer. This strategy has the potential to aid structure determination of proteins that present particular experimental challenges and are not conducive to more conventional crystallization strategies (e.g., membrane proteins). Structural genomics initiatives may also benefit from this approach as a way to crystallize problematic proteins of significant interest.

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Bacterial chaperonin, GroEL, together with its co-chaperonin, GroES, facilitates the folding of a variety of polypeptides. Experiments suggest that GroEL stimulates protein folding by multiple cycles of binding and release. Misfolded proteins first bind to an exposed hydrophobic surface on GroEL. GroES then encapsulates the substrate and triggers its release into the central cavity of the GroEL/ES complex for folding. In this work, we investigate the possibility to facilitate protein folding in molecular dynamics simulations by mimicking the effects of GroEL/ES namely, repeated binding and release, together with spatial confinement. During the binding stage, the (metastable) partially folded proteins are allowed to attach spontaneously to a hydrophobic surface within the simulation box. This destabilizes the structures, which are then transferred into a spatially confined cavity for folding. The approach has been tested by attempting to refine protein structural models generated using the ROSETTA procedure for ab initio structure prediction. Dramatic improvements in regard to the deviation of protein models from the corresponding experimental structures were observed. The results suggest that the primary effects of the GroEL/ES system can be mimicked in a simple coarse-grained manner and be used to facilitate protein folding in molecular dynamics simulations. Furthermore, the results Sur port the assumption that the spatial confinement in GroEL/ES assists the folding of encapsulated proteins.