947 resultados para mono-sized granules


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Physical activity has been scientifically discussed as fundamental in the process of healthy ageing. Hence, this study aimed at determining the factors that influence older people to perform physical activities. The complete IPAQ (International Physical Activity Questionnaire) was applied to a population-based sample consisting of 364 elderly persons in the city of Botucatu, São Paulo, Brazil. Days of physical activity performed by the older people were considered by taking into account household and leisure activities. Models for count data were fitted by including socio-demographic variables as well as those related to life satisfaction. It was shown that housework physical-activity performance is associated with female, who predominantly showed to be more active in all levels. Male seemed to be more predisposed to perform lighter recreation, sports and leisure-time physical activities, such as walking. Additionally, poor schooling showed to be decisive for not performing physical activities both at home and during leisure.

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Protocols for rapid habitat evaluation and the biotic indices used in biomonitoring of streams in Brazil provide useful information about water quality and modifications in the ecosystem. However, the interpretation of their results is limited. Previous studies pointed out the low sensitivity of those indices to measure the quality of low-order streams, since they only measure organic impacts. Environmental degradation of these streams is mainly related to impacts caused by landscape change, such as erosion, siltation, channel change, loss of riparian vegetation, and reduction in water flow. The streams of the Serra do Japi are under some of these impacts, caused by agricultural activities. In this study, we evaluated whether the reduction of natural characteristics in these environments would decrease water quality. The Protocol of Habitat Diversity was affected by the impacts of agricultural activities. However, the other three biotic indices: Biological Monitoring Working Party Score System, Average Score Per Taxon, and Index of Benthic Community were not as sensitive to those impacts, since they all indicated a high water quality. An adaptation of the attributes and the scoring system is suggested for defining better policies for the conservation of this area.

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Medium and large-sized mammals control invertebrate and vertebrate populations and are important seed dispersers. These animals are losing their territory and living range due to deforestation and the fragmentation of natural areas, particularly in the Atlantic Forest and Cerrado. The Private Reserve of Natural Heritage (PRNH) Amadeu Botelho is isolated from other forest fragments and is thus a wildlife refuge in the region of Jaú, central-western region of state of São Paulo, southeastem Brazil. Animals as such as the puma (Puma concolor), ocelot (Leopardus pardalis) and jaguarundi (Puma yagouaroundi) have been sighted in the reserve by wildlife guards and residents. This reserve, which belongs to “Santo Antônio dos Ipês” farm, is surrounded by several plantations, and is very close to the center of the city of Jaú. In addition to surveying the mammal species in the reserve, this study diagnosed the influence of the farm’s activities and the proximity to the center of the municipality of Jaú on the fauna under study

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Protecting a network against link failures is a major challenge faced by network operators. The protection scheme has to address two important objectives - fast recovery and minimizing the amount of backup resources needed. Every protection algorithm is a tradeoff between these two objectives. In this paper, we study the problem of segment protection. In particular, we investigate what is the optimal segment size that obtains the best tradeoff between the time taken for recovery and minimizing the bandwidth used by the backup segments. We focus on the uniform fixed-length segment protection method, where each primary path is divided into fixed-length segments, with the exception of the last segment in the path. We observe that the optimal segment size for a given network depends on several factors such as the topology and the ratio of the costs involved.

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This document style is intended for reading onscreen. It creates a two-page spread that fits on a single screen (of 1024 x 768 pixels), with type that remains readable at 75% magnification. It includes design and typographic settings to accommodate common text elements: headings, subtitles, extracts, etc. The font is Lucida Sans Unicode, set single-spaced. It is a sans serif font, which allows for greater readability at smaller sizes and onscreen. The basic text size is 11 point. The font is engi¬neered with a tall line-height, so that even set “solid” (i.e., single-spaced) there is ample “leading” between the lines for clear reading. The overall design is “left aligned”—that is all titles, subtitles, headings, etc. are lined up on the left margin. Paragraphs are justified, for easier reading; titles, headings, references, captions, and endnotes are not justified. The two files attached to this documents are: Screen SansSerif file.doc = a blank MS Word file with these page and type specifications already loaded. Enter (or paste) your text into this file and Save under a new name. Screen SansSerif template.dot = an MS Word template; use this to create a new blank document. Templates are generally stored in a folder in Program Files > Microsoft Office > Templates The main document contains sample pages and specifications for the type, margins, settings, etc.

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Many animal species make use of ultraviolet (UV) light in a number of behaviors, such as feeding and mating. The goldfish (Carassius auratus) is among those with a UV photoreceptor and pronounced UV sensitivity. Little is known, however, about the retinal processing of this input. We addressed this issue by recording intracellularly from second-order neurons in the adult goldfish retina. In order to test whether cone-driven horizontal cells (HCs) receive UV cone inputs, we performed chromatic adaptation experiments with mono- and biphasic HCs. We found no functional evidence of a projection from the UV-sensitive cones to these neurons in adult animals. This suggests that goldfish UV receptors may contact preferentially triphasic HCs, which is at odds with the hypothesis that all cones contact all cone-driven HC types. However, we did find evidence of direct M-cone input to monophasic HCs, favoring the idea that cone-HC contacts are more promiscuous than originally proposed. Together, our results suggest that either UV cones have a more restricted set of post-synaptic partners than the other three cone types, or that the UV input to mono- and biphasic HCs is not very pronounced in adult animals.

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This work aims to evaluate the cytocompatibility of injectable and moldable restorative biomaterials based on granules of dense or porous biphasic calcium phosphates (BCPs) with human primary mesenchymal cells, in order to validate them as tools for stem cell-induced bone regeneration. Porous hydroxyapatite (HA) and HA/beta-tricalcium phosphate (beta-TCP) (60: 40) granules were obtained by the addition of wax spheres and pressing at 20 MPa, while dense materials were compacted by pressing at 100 MPa, followed by thermal treatment (1100 degrees C), grinding, and sieving. Extracts were prepared by 24-h incubation of granules on culture media, with subsequent exposition of human primary mesenchymal cells. Three different cell viability parameters were evaluated on the same samples. Scanning electron microscopy analysis of the granules revealed distinct dense and porous surfaces. After cell exposition to extracts, no significant differences on mitochondrial activity (2,3-bis(2-methoxy-4-nitro-5-sulfophenly)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide) or cell density (Crystal Violet Dye Elution) were observed among groups. However, Neutral Red assay revealed that dense materials extracts induced lower levels of total viable cells to porous HA/beta-TCP (P < 0.01). Calcium ion content was also significantly lower on the extracts of dense samples. Porogenic treatments on BCP composites do not affect cytocompatibility, as measured by three different parameters, indicating that these ceramics are well suited for further studies on future bioengineering applications.

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The monodentate cis-[Ru(phen)(2)(hist)(2)](2+) 1R and the bidentate cis-[Ru(phen)(2)(hist)](2+) 2A complexes were prepared and characterized using spectroscopic (H-1, (H-1-H-1) COSY and (H-1-C-13) HSQC NMR, UV-vis, luminescence) techniques. The complexes presented absorption and emission in the visible region, as well as a tri-exponential emission decay. The complexes are soluble in aqueous and non-aqueous solution with solubility in a buffer solution of pH 7.4 of 1.14 x 10(-3) mol L-1 for (1R + 2A) and 6.43 x 10(-4) mol L-1 for 2A and lipophilicity measured in an aqueous-octanol solution of -1.14 and -0.96, respectively. Photolysis in the visible region in CH3CN converted the starting complexes into cis-[Ru(phen)(2)(CH3CN)(2)](2+). Histamine photorelease was also observed in pure water and in the presence of BSA (1.0 x 10(-6) mol L-1). The bidentate coordination of the histamine to the ruthenium center in relation to the monodentate coordination increased the photosubstitution quantum yield by a factor of 3. Pharmacological studies showed that the complexes present a moderate inhibition of AChE with an IC50 of 21 mu mol L-1 (referred to risvagtini, IC50 181 mu mol L-1 and galantamine IC50 0.006 mu mol L-1) with no appreciable cytotoxicity toward to the HeLa cells (50% cell viability at 925 mu mol L-1). Cell uptake of the complexes into HeLa cells was detected by fluorescence confocal microscopy. Overall, the observation of a luminescent complex that penetrates the cell wall and has low cytotoxicity, but is reactive photochemically, releasing histamine when irradiated with visible light, are interesting features for application of these complexes as phototherapeutic agents.

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A new method for analysis of scattering data from lamellar bilayer systems is presented. The method employs a form-free description of the cross-section structure of the bilayer and the fit is performed directly to the scattering data, introducing also a structure factor when required. The cross-section structure (electron density profile in the case of X-ray scattering) is described by a set of Gaussian functions and the technique is termed Gaussian deconvolution. The coefficients of the Gaussians are optimized using a constrained least-squares routine that induces smoothness of the electron density profile. The optimization is coupled with the point-of-inflection method for determining the optimal weight of the smoothness. With the new approach, it is possible to optimize simultaneously the form factor, structure factor and several other parameters in the model. The applicability of this method is demonstrated by using it in a study of a multilamellar system composed of lecithin bilayers, where the form factor and structure factor are obtained simultaneously, and the obtained results provided new insight into this very well known system.

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It is known that current trends on bone bioengineering seek ideal scaffolds and explore innovative methods to restore tissue function. In this way, the objective of this study was to evaluate the behavior of anorganic bovine bone as osteoblast carrier in critical-size calvarial defects. MC3T3-E1 osteoblast cells (1x10(5) cells/well) were cultured on granules of anorganic bovine bone in 24-well plates and after 24 h these granules were implanted into rat critical-size calvarial defects (group Biomaterial + Cells). In addition, other groups were established with different fillings of the defect: Blood Clot (negative control); Autogenous Bone (positive control); Biomaterial (only granules) and Cells (only MC3T3-E1 cells). After 30 days, the animals were euthanized and the calvaria were technically processed in order to allow histological and morphometric analysis. It was possible to detect blood vessels, connective tissue and newly formed bone in all groups. Particularly in the Biomaterial + Cells group, it was possible to observe a profile of biological events between the positive control group (autogenous bone) and the group in which only anorganic bovine granules were implanted. Altogether, the results of the present study showed that granules of anorganic bovine bone can be used as carrier to osteoblasts and that adding growth factors at the moment of implantation should maximize these results.

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[EN]This work presents the measurements made to define the temperature−composition curves for a set of binary systems composed of several pyridinium-based ionic liquids (ILs) [bpy][BF4] and [bYmpy][BF4] (Y = 2,3,4) with mono- and dihaloalkanes (Cl and Br) in the temperature interval [280−473] K and at atmospheric pressure. With the exception of the short chain dichloroalkanes (1,1- and 1,2-), all the compounds present some degree of immiscibility with the ionic liquids selected.

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Synthese und Charakterisierung neuer funktionalisierter Mono- und Bis-tetrahydro-pyrrolo[3,4-b]carbazole als potentielle DNA-Liganden In der Carbazol-Chemie sollen neue anellierte Verbindungen mit potentieller DNA-Affinität und damit verbundener Antitumoraktivität entwickelt werden. Auf molekularer Ebene sind DNA-Interkalation oder DNA-Rinnenbindung zu erwarten. Darauf aufbauend wurden in Anlehnung an literaturbekannte Cytostatika Mono- und Bis-tetrahydropyrrolo[3,4-b]carbazole synthetisiert, die zur Entwicklung neuer Leitstrukturen bzw. -substanzen beitragen können.In der vorliegenden Arbeit wurde als synthetische Schlüsselreaktion die in unserem Arbeitkreis etablierte Indol-2,3-chinodimethan-Diels-Alder-Reaktion mit geeigneten cyclischen Mono- und Bismaleinimiden als Dienophilen weiterführend genutzt. Auf Grund des Aufbaus von künftigen Struktur-Wirkungsbeziehungen wurden variable Linker zwischen die beiden zu verbindenden Pyrrolotetrahydrocarbazole eingeführt. Diese waren aliphatischer und diamidischer Natur. Diamidische Strukturelemente wurden im Hinblick auf die Entwicklung neuer Peptidomimetika eingeführt. Deren Synthese gelang zum einen über die gemischte Säureanhydrid-Methode und zum anderen über die Azolid-Methode. Die Struktursicherung der als Cycloaddukte erhaltenen Tetrahydrocarbazole erfolgte mittels Standardverfahren (1D-, 2D-NMR-, IR-Spektroskopie und Massenspektrometrie).Enantiomere bzw. Diastereomere chiraler Wirkstoffe unterscheiden sich stark in ihren pharmakologischen Eigenschaften, deshalb müssen Verfahren entwickelt werden, um diese Substanzen gegebenenfalls auch in enantiomerenreiner Form darstellen zu können. Die Racemate der Monotetrahydrocarbazole und die Racemate sowie die dazu diastereomeren meso-Formen der Bistetrahydrocarbazole, die bei der Reaktion entstehen, konnten erstmals mittels chiraler HPLC analytisch getrennt werden.In einer der Synthese ergänzten theoretischen Studie wurde Computer-Molecular-Modelling zur Problematik der Diels-Alder-Reaktion durchgeführt, außerdem wurden kraftfeld-mechanische Berechnungen zur Konformationsanalyse der 'einfachen' Monotetrahydro-carbazole herangezogen und darauf aufbauend schließlich einfache DNA-Docking-Experimente zur ersten Abschätzung des DNA-Binde-Verhaltens der synthetisierten Verbindungen vorgenommen.