134 resultados para conhecimento físico


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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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This work investigates the using of kitchens of the apartments of PLANO 100 in Natal-RN, through one method s set of the functional and behavior evaluation. The theme was selected through of the emergence of the many questions that sought to understand what manners how individuals relates to the constructed space, what was the possible changes caused by these relation, also verifying how this space interferes in a daily life of theirs users. This research to search answers what to improve of the study s object and in futures production s architectonic too. The used approach combined an overview of new kinds of familiar arrangements and the evolution process of the brazilian s kitchens within social context of Brazil, with APO (Post-Occupation Evaluation), techniques through a physical space survey, questionnaires and interviews with users. Beyond to APO s implements were applied behavior setting s techniques too, what presented the most knowledge about to satisfactions levels pointed by the users

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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It is important to evaluate the quality of water for proper management of these resources, since the increase of environmental degradation and the multiple use of water resources are decreasing the quality of water consumed by living beings. The objective of this study was to characterize the phytoplankton community and its variations during periods of dray and rain in Jiqui Lake located in Parnamirim, RN. It was also aimed to analyze the physical and chemical factors of this environment, in order to contribute to the knowledge of water quality used for human consumption. The collection of water samples were carried out in September 2008 to August 2009. The collection of the phytoplankton community was carried out in four sampling sites (surface, bottom, margin of the lake without macrophytes and site dominated by macrophytes). Phytoplankton was collected using plankton net of 20m. The analysis of nutrients and identification of phytoplankton were performed in the laboratory. The results indicate that concentration of chlorophyll a was high in the bottom with mean value of 1.07 μgL-1 (SD ± 1.61). During the study period there was a dominance of the following species: Euglena gracilis, Trachelomonas sp, Cyclotellas sp, Gomphonema apuncto, Navicula cuspidata var. cuspidata, Navicula sp, Rhopalodia gibba. There was homogeneity between limnological values in the four study sites, with significant difference between the periods of drought and rain. The Jiqui Lake is considered oligotrophic due to its low concentrations of chlorophyll a, high transparency and low levels of nutrients. The values of BOD and chlorophyll a concentration remained below the permitted standards existing for freshwaters in Brazil, thus the water from Lake Jiqui is of good quality, suitable for human consumption.

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Galactans are polysaccharides sulfated present in the cell wall of red algae. Carrageenans are galactans well known in the food industry as gelling polysaccharides and for induce inflammatory process in rodents as animal model. The extraction of polysaccharides from A. multifida has been carried out by proteolysis and precipitation in different volumes of acetone, which produced three fractions (F1, F2, and FT). Chemical and physical analyses revealed that these fractions are sulfated galactan predominantly. Results of the antioxidant activity assays showed that all of these fractions have antioxidant activity and that was associated with sulfate content of the analysis of reducing power and total antioxidant capacity. However, these fractions were not effective against lipid peroxidation. The fraction FT presented higher activity on the APTT test at 200 μg (> 240 s). The assessment of the hemolytic activity showed that the FT fraction has the best activity, increasing lyses by the complement system to 42.3% (50 μg) (p< 0,001). The fraction FT showed the best yield, anticoagulant and hemolytic activity between the three fractions and therefore it was choose for the in vivo studies. The Inflammation assessment using the FT fraction (50 mg / kg MB) showed that the cellular migration and the IL-6 production increased 670.1% (p< 0,001) and 531.8% (p< 0,001), respectively. These results confirmed its use as an inflammation inducer in animal model. Cytotoxicity assay results showed that all fractions have toxic effects on 3T3 and HeLa cells after exposition of 48 hours, except when 100 μg for both F1 and FT were used. These results arise the discussion whether these polysaccharides it should be used as additive in foods, cosmetics and medicines.

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This study examines the physical and chemical composition and the pharmacological effects of brown seaweed FRF 0.8 Lobophora variegata. Fractionation of the crude extract was done with the concentration of 0.8 volumes of acetone, obtaining the FRF 0.8. The physicochemical characterization showed that it was a fucana sulfated. Anti-inflammatory activity was assessed by paw edema model by the high rates of inhibition of the edema and the best results were in the fourth hour after induction (100 ± 1.4% at the dose of 75 mg / kg) and by the strong inhibitory activity of the enzyme myeloperoxidase (91.45% at the dose of 25 mg / kg). The hepataproteção was demonstrated by measurements of enzymatic and metabolic parameters indicative of liver damage, such as bilirubin (reduction in 68.81%, 70.68% and 68.21% for bilirubin total, direct and indirect, respectively at a dose of 75 mg / kg), ALT, AST and γ-GT (decrease of 76.93%, 44.58% and 50% respectively at a dose of 75 mg / kg) by analysis of histological slides of liver tissue, confirming that hepatoprotective effect the polymers of carbohydrates, showing a reduction in tissue damage caused by CCl4 and the inhibition of the enzyme complex of cytochrome P 450 (increasing sleep time in 54.6% and reducing the latency time in 71.43%). The effectiveness of the FRF 0.8 angiogenesis was examined in chorioallantoic membrane (CAM) of fertilized eggs, with the density of capillaries evaluated and scored, showing an effect proangigênico at all concentrations tested FRF (10 mg- 1000 mg). The FRF showed antioxidant activity on free radicals (by inhibiting Superoxide Radical in 55.62 ± 2.10%, Lipid Peroxidation in 100.15 ± 0.01%, Hydroxyl Radical in 41.84 ± 0.001% and 71.47 Peroxide in ± 2.69% at concentration of 0.62 mg / mL). The anticoagulant activity was observed with prolongation of activated partial thromboplastin time (aPTT) at 50 mg (> 240 s), showing that its action occurs in the intrinsic pathway of the coagulation cascade. Thus, our results indicate that these sulfated polysaccharides are an important pharmacological target

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Worldwide, families Carangidae and Rachycentridae represent one of the groups most important commercial fish, used for food, and great potential for marine aquaculture. However, the genetic bases that can underpin the future cultivation of these species, cytogenetic between these aspects are very weak. The chromosomal patterns have provided basic data for the exploration of biotechnological processes aimed at handling chromosomal genetic improvement, such as induction of polyploidy, androgenesis and ginogenesis, as well as obtaining monosex stocks and interspecific hybridizations. This paper presents a comprehensive cytogenetic survey in 10 species, seven of the family Carangidae and the monotypic family Rachycentridae. Classical cytogenetic analysis and in situ mapping of multigene sequences were employed, and additionally for the genus Selene and morphotypes of Caranx lugubris, comparisons were made using geometric morphometrics. In general, conservative species exhibit a marked chromosome number (2n=48). Although present in large part, different karyotypic form, retain many characteristics typical of chromosomal Order Perciformes, the high number of elements monobrachyal, Ag-NORs/18S rDNA sites and heterochromatin simply reduced, preferably centromeric. The main mechanisms involved in karyotypic diversification are the pericentric inversions, with secondary action of centric fusions. In addition to physical mapping and chromosome detail for the species are presented and discussed patterns of intra-and interspecific diversity, cytotaxonomic markers. This data set provides a better understanding of these patterns caryoevolutyonary groups and conditions for the development of protocols based on Biotechnology for chromosomal manipulation Atlantic these species

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There are ores of clay in Piauí State that are used for red structural ceramics, which are naturally contaminated with calcareous vein. This is one thing that impedes its exploration in an adequate way, especially for tile production. The present work aims at verifying the influence of the calcareous contents in the technological structural ceramics area, seeking to determine a maximum permissible calcareous proportion/contents in the ceramic mass using the patterns of the local industry production. For the consecution of this paper, it was characterized the clay and calcareous material by FRX, DRX, TGA and DTA. It was also configurated by extrusion and burnt in the temperatures of 850°C, 900°C, 950°C and 1000°C pieces of the corpus with 0, 5, 10, 15 e 20% of calcareous proportion. After that, it was carried out technological samples of linear retraction, water absortion, apparent porosity, specific apparent mass and mechanic resistance. The results showed the possibility of using calcareous in the ceramic mass and in some cases the technological properties got better

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Physical-chemical properties of Ti are sensible to the presence of interstitial elements. In the case of thermochemical treatments plasma assisted, the influence of different active species is not still understood. In order to contribute for such knowledge, this work purposes a study of the role played by the active species atmosphere into the Ar N2 CH4 carbonitriding plasma. It was carried out a plasma diagnostic by OES (Optical Emission Spectroscopy) in the z Ar y N2 x CH4 plasma mixture, in which z, y and x indexes represent gas flow variable from 0 to 4 sccm (cm3/min). The diagnostic presents abrupt variations of emission intensities associated to the species in determined conditions. Therefore, they were selected in order to carry out the chemical treatment and then to investigate their influences. Commercial pure Ti disks were submitted to plasma carbonitriding process using pre-established conditions from the OES measurements while some parameters such as pressure and temperature were maintained constant. The concentration profiles of interstitial elements (C and N atoms) were determined by Resonant Nuclear Reaction Analysis (NRA) resulting in a depth profile plots. The reactions used were 15N(ρ,αγ)12C and 12C(α,α)12C. GIXRD (Grazing Incidence X-Ray Diffraction) analysis was used in order to identify the presence of phases on the surface. Micro-Raman spectroscopy was used in order to qualitatively study the carbon into the TiCxN1 structure. It has been verified which the density species effectively influences more the diffusion of particles into the Ti lattice and characteristics of the layer formed than the gas concentration. High intensity of N2 + (391,4 nm) and CH (387,1 nm) species promotes more diffusion of C and N. It was observed that Hα (656,3 nm) species acts like a catalyzer allowing a deeper diffusion of nitrogen and carbon into the titanium lattice.

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The titanium and titanium alloys are widely used as biomaterial in biomedical device and so research have been developed aiming to improve and/or better to understand interaction biomaterial/biological environment. The process for manufacturing of this titanium implants usually involves a series of thermal and mechanical processes which have consequence on the final product. The heat treatments are usually used to obtain different properties for each application. In order to understand the influence of these treatments on the biological response of the surface, it was done, in this work, different heat treatments in titanium and analyzed their influence on the morphology, adhesion and proliferation of the pre-osteoblastic cells (MC3T3-E1). For such heat-treated titanium disks were characterized by optical microscopy, contact angle, surface energy, roughness, microhardness, X-ray diffraction and scanning through the techniques (BSE, EDS and EBSD). For the analysis of biological response were tested by MTT proliferation, adhesion by crystal violet and β1 integrin expression by flow cytometry. It was found that the presence of a microstructure very orderly, defined by a chemical attack, cells tend to stretch in the same direction of orientation of the material microstructure. When this order does not happen, the most important factor influencing cell proliferation is the residual stress, indicated by the hardness of the material. This way the disks with the highest level state of residual stress also showed increased cell proliferation

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This research was motivated by the requirement of asbestos s replacement in building systems and the need to generate jobs and income in the country side of the state of Bahia, Brazil. The project aimed at using fibers from licuri leaves (syagrus coronata), an abundant palm in the region, to produce composites appropriate for the sustainable production of cement fibre reinforced products in small plants. The composites were produced in laboratory using Portland cement CP-II-F32, sand, water, licuri palm fiber contents of 1.0, 1.5 and 2.0% by weight of binder (two different fiber length) and metakaolin. The latter was chosen as an additional binder for its efficiency to reduce the alkalinity of cementitious matrixes therefore preventing the degradation of vegetable fibers. The characterization of the composite components was carried out by sieving and laser particle size analyses, thermal analysis, fluorescence and X-ray diffraction. The composites performance was evaluated by 3- point-bending tests, compressive strength, ultrasound module of elasticity, free and restrained shrinkage, water capillarity absorption and apparent specific gravity. It has been found that the addition of fibers increased the time to onset of cracking over 200.00% and a 25% reduction in cracks opening in the restrained shrinkage test. The capillary absorption reduced about 25% when compared to fiber-free composites. It was also observed with regard to flexural strength, compressive strength and specific gravity, that the addiction of fibers did not affect the composite performance presenting similar results for compounds with and without fibers. In general it can be stated that the reinforced composite fibers of palm licuri presents physical and mechanical characteristics which enable them to be used in the intended proposals of this research

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The state of Rio Grande do Norte presents a great potentiality for the production of ceramic tiles because of having natural raw material in quantity and quality making its economical exploration possible, beyond the great energetic differential of the state, the natural gás. This works aims to study the influence of the dolomite and granulometry concentration and calcinations temperature in the obtaining of formulations for porous coverings which have to be coherent to the project,s specifications. The experiments have involved the physical-chemical and mineralogical characterizations of raw materials and mechanical tests in the dry and burnt proof bodies preceding a mixture experiment planning with the use of the response surface methodology, in order to get the best raw materials combinations to produce a ceramic mass with specific properties. The twelve ceramic masses studied in this work were prepared by the via dry process, characterized, shaped by uniaxial pressing and sinterized in the temperatures of 940ºC, 1000ºC, 1060ºC, 1120ºC and 1180ºC, using a fast burning cycle. The crystalline phases formed during the sintering in the temperatures in study have revealed the presence of anorthite and diopside beyond quartz with a remaining phase. These phases were the main responsible ones by the physical- mechanical properties of the sinterized proof bodies. The proof bodies after the sintering stage have presented water absorption higher than 10% and a good dimensional stability in all studied temperatures. However, the flexural breaking strength results in the temperatures of 940ºC, 1000ºC and 1060ºC, under the temperature zone of the vitrification of ceramic whiteware do not reach the flexural breaking strength specific for the porous wall tile (15 MPa), but in the temperature of 1120ºC next to the vitrification temperature zone, some whiteware ceramic (formulations) has reached the specified value for the porous wall tile. The results of this work have showed that the studied raw materials have great importance for used in the production of porous wall tiles (BIII)

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Introdução: Os hormônios estrogênicos possuem importante papel na defesa contra as espécies reativas do oxigênio, fato que se evidencia na maior incidência de doenças cardiovasculares e neurodegenerativas após a menopausa. O exercício físico melhora as defesas antioxidantes, contudo em altas cargas e em baixas concentrações de estrógeno possui efeito aditivo ao dano oxidativo. O ácido α-lipóico possui uma ampla gama de ação antioxidante e poderia contribuir para diminuição do dano nestas condições. Objetivo: O objetivo deste estudo é caracterizar a ação do ácido α-lipóico sobre a adaptação antioxidante e funções reprodutivas de ratas submetidas a natação moderada. Material e métodos: Os animais foram submetidos a natação diária (1 hora) e sacrificados após 30, 60 e 90 dias. Os animais foram divididos em controles sedentários e exercitados; suplementados (ácido α-lipóico 100mg/Kg/dia) sedentários e exercitados e animais ovariectomizados e suplementados com ácido lipóico. Avaliou-se diariamente o ciclo estral e os seguintes marcadores de estresse oxidativos foram mensurados em fígado e sangue: atividade enzimática da SOD, GPx e CAT, além do SRAT e GSH. Resultados: O protocolo de exercício aumentou a duração do ciclo estral no grupo controle exercitado, sobretudo na fase diestral. Neste mesmo grupo, houve diminuição da lipoperoxidação com melhora da atividade antioxidante da SOD e GPx. O grupo exercitado e suplementado não apresentou alteração na duração do ciclo estral e manteve os benefícios sobre o sistema antioxidante antes observado nos animais exercitados. A suplementação antioxidante juntamente com a natação em períodos superiores a 30 dias, diminuiu o processo de adaptação antioxidante quando comparado aos animais somente exercitados. Nos animais ovariectomizados, o exercício e a suplementação com ácido lipóico não promoveu adaptação antioxidante ao contrário dos demais grupos. Conclusão: O aumento na duração do ciclo estral e a melhora nos marcadores de estresse oxidativo seriam uma resposta adaptativa frente ao exercício moderado. O ácido lipóico impediu a alteração no ciclo induzida pelo exercício, mas preservou a melhoria no sistema antioxidante. A depleção estrogênica provocada pela ovariectomia eleva o potencial de dano oxidativo gerado pelo exercício. A ação antioxidante do LA na presença de estrógeno diminuiu excessivamente o dano oxidativo, comprometendo a adaptação antioxidante a natação. Nos animais ovariectomizados, contudo, o AL promoveu adaptação antioxidante ao exercício

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analisar o efeito do treinamento aeróbio periodizado sobre a aptidão cardiorrespiratória e respostas afetivas em mulheres com síndrome dos ovários policísticos (SOP) e II) investigar se o exercício aeróbio realizado na zona de prazer para essa população atende a recomendação do American College of Sports Medicine (ACSM) no que se refere à intensidade para melhoria da saúde. Metodologia: foram incluídas mulheres na faixa etária entre 18 e 34 anos, com diagnóstico de SOP de acordo com o Consenso de Rotterdam. Para o subestudo I, oito pacientes sedentárias participaram de 16 semanas de treinamento aeróbio com incrementos mensais de intensidade: fase 1 = 60-70% da frequência cardíaca máxima (FCmax); fase 2 = 70-75% da FCmax; fase 3 = 75-80% da FCmax; fase 4 = 80-85% da FCmax. A intervenção foi realizada três vezes por semana, 40 minutos por sessão. Em todas as sessões foram registradas as respostas afetivas (Feeling Scale -5/+5) e a percepção subjetiva do esforço (escala de Borg CR 6-20). Antes e após a intervenção, as voluntárias realizaram teste ergoespirométrico. Para o subestudo II, 11 pacientes realizaram duas sessões de exercício aeróbio na zona de prazer, sendo registrados parâmetros relativos à demanda física através de receptor de GPS (Global Positioning System) de pulso com cardiofrequencímetro acoplado. As pacientes foram instruídas a realizar 40 minutos de exercício guiadas pelas âncoras verbais bom e muito bom (+3 e +5 na Feeling Scale). Resultados: no subestudo I, após 16 semanas de treinamento, houve aumento da aptidão cardiorrespiratória máxima (17,3%) e submáxima (21,5%). As respostas afetivas variaram entre bom (+3,1 ± 0,8) e razoavelmente bom xi (1,0 ± 0,9) e a percepção subjetiva do esforço entre muito leve a leve (10,2 ± 0,7) e um pouco difícil (12,7 ± 0,6) durante a intervenção. No subestudo II, as pacientes exercitaram-se a ~72,5 ± 6% da FC máxima, ~78,5 ± 6% da FC no limiar anaeróbio e passaram > 95% do tempo em intensidade moderada (~82%) e vigorosa (~16%) durante as sessões experimentais. Em média, as voluntárias reportaram as sessões como fácil (percepção subjetiva do esforço da sessão ~2,2 ± 0,7). Conclusões: o programa de treinamento aeróbio periodizado aumentou a aptidão cardiorrespiratória das pacientes analisadas e foi percebido como uma intervenção prazerosa. Adicionalmente, exercício aeróbio realizado de forma prazerosa atende a recomendação do ACSM no que se refere à intensidade para melhoria da saúde