28 resultados para Scientific community


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A catalyst of great interest to the scientific community tries to unite the structure of ordered pore diameter from mesoporous materials with the properties of stability and acid activity to microporous zeolites. Thus a large number of materials was developed in the past decades, which although being reported as zeolites intrinsically they fail to comply with some relevant characteristics to zeolites, and recently were named zeolitic materials of high accessibility. Among the various synthesis strategies employed, the present research approaches the synthesis methods of crystallization of silanized protozeolitic units and the method of protozeolitic units molded around surfactant micelles, in order for get materials defined as hierarchical zeolites and micro-mesoporous hybrid materials, respectively. As goal BEA/MCM-41 hybrid catalysts with bimodal pore structure formed by nuclei of zeolite Beta and cationic surfactant cetyltrimethylammonium were developed. As also was successfully synthesized the hierarchical Beta zeolite having a secondary porosity, in addition to the typical and uniform zeolite micropores. Both catalysts were applied in reactions of catalytic cracking of high density polyethylene (HDPE), to evaluate its properties in catalytic activity, aiming at the recycling of waste plastics to obtain high value-added raw materials and fuels. The BEA/MCM-41 hybrid materials with 0 days of pre-crystallization did not show enough properties for use in catalytic cracking reactions, but they showed superior catalytic properties compared to those ordered mesoporous materials of Al-MCM-41 type. The structure of Beta zeolite with hierarchical porosity leads the accessibility of HDPE bulky molecules to active centers, due to high external area. And provides higher conversion to hydrocarbons in the gasoline range, especially olefins which have great interest in the petrochemical industry

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The game industry has been experiencing a consistent increase in production costs of games lately. Part of this increase refers to the current trend of having bigger, more interactive and replayable environments. This trend translates to an increase in both team size and development time, which makes game development a even more risky investment and may reduce innovation in the area. As a possible solution to this problem, the scientific community is focusing on the generation of procedural content and, more specifically, on procedurally generated levels. Given the great diversity and complexity of games, most works choose to deal with a specific genre, platform games being one of the most studied. This work aims at proposing a procedural level generation method for platform/adventure games, a fairly more complex genre than most classic platformers which so far has not been the subject of study from other works. The level generation process was divided in two steps, planning and viusal generation, respectively responsible for generating a compact representation of the level and determining its view. The planning stage was divided in game design and level design, and uses a goaloriented process to output a set of rooms. The visual generation step receives a set of rooms and fills its interior with the appropriate parts of previously authored geometry

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The loss of Earth´s biodiversity is a major concern for the international scientific community and megadiverse countries like Brazil are paramount for discussions about the overall situation of the planet. The Caatinga biome is probably one of the most threatened in Brazil and the implementation of Conservation Units (CU) represents a measure for protecting its natural resources and biodiversity. The Station Ecological of Seridó (ESEC-Serido) is one of the few CU in the Caatinga of Rio Grande do Norte State (NE Brazil) and interacts with several neighboring communities and settlements. However the ESEC does not integrate environmental perception feedback from the local communities in its management plan. Considering this, the present articles aims at identifying the perceptions and concepts of such communities regarding environmental issues and biodiversity as well as indicate strategies to improve the administration of this CU. In order to achieve these goals, a review of the specialized literature was carried out and a research tool based on Environmental Perception was developed in the form of structured interviews applied to the persons from communities neighboring the ESEC. These interviews were later processed through content analysis. The concepts and perceptions obtained through this analysis show that the people from the environs are aware of the main problems faced by ESEC-Seridó, as well as the strategies to address them

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Currently the interest in large-scale systems with a high degree of complexity has been much discussed in the scientific community in various areas of knowledge. As an example, the Internet, protein interaction, collaboration of film actors, among others. To better understand the behavior of interconnected systems, several models in the area of complex networks have been proposed. Barabási and Albert proposed a model in which the connection between the constituents of the system could dynamically and which favors older sites, reproducing a characteristic behavior in some real systems: connectivity distribution of scale invariant. However, this model neglects two factors, among others, observed in real systems: homophily and metrics. Given the importance of these two terms in the global behavior of networks, we propose in this dissertation study a dynamic model of preferential binding to three essential factors that are responsible for competition for links: (i) connectivity (the more connected sites are privileged in the choice of links) (ii) homophily (similar connections between sites are more attractive), (iii) metric (the link is favored by the proximity of the sites). Within this proposal, we analyze the behavior of the distribution of connectivity and dynamic evolution of the network are affected by the metric by A parameter that controls the importance of distance in the preferential binding) and homophily by (characteristic intrinsic site). We realized that the increased importance as the distance in the preferred connection, the connections between sites and become local connectivity distribution is characterized by a typical range. In parallel, we adjust the curves of connectivity distribution, for different values of A, the equation P(k) = P0e

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Complex systems have stimulated much interest in the scientific community in the last twenty years. Examples this area are the Domany-Kinzel cellular automaton and Contact Process that are studied in the first chapter this tesis. We determine the critical behavior of these systems using the spontaneous-search method and short-time dynamics (STD). Ours results confirm that the DKCA e CP belong to universality class of Directed Percolation. In the second chapter, we study the particle difusion in two models of stochastic sandpiles. We characterize the difusion through diffusion constant D, definite through in the relation h(x)2i = 2Dt. The results of our simulations, using finite size scalling and STD, show that the diffusion constant can be used to study critical properties. Both models belong to universality class of Conserved Directed Percolation. We also study that the mean-square particle displacement in time, and characterize its dependence on the initial configuration and particle density. In the third chapter, we introduce a computacional model, called Geographic Percolation, to study watersheds, fractals with aplications in various areas of science. In this model, sites of a network are assigned values between 0 and 1 following a given probability distribution, we order this values, keeping always its localization, and search pk site that percolate network. Once we find this site, we remove it from the network, and search for the next that has the network to percole newly. We repeat these steps until the complete occupation of the network. We study the model in 2 and 3 dimension, and compare the bidimensional case with networks form at start real data (Alps e Himalayas)

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Prospecting pharmacological active polysaccharides from agricultural byproducts, such as corncobs, is an underexplored practice in the scientific community. Thus, this work aims to expand knowledge about pharmacological activities of polysaccharides extracted from corncobs. From corn cob flour a extract was obtained by ultrasound waves in an alkaline medium, and the end of the process the product was termed PECC (polysaccharidic extract from corncobs). This extract was physicochemical characterized and evaluated by in vitro assays as an antioxidant, cytotoxic, anticoagulant and imunomodulator agent. Results indicated significant activity metal chelating by PECC, and the use of PECC in cell culture cells showed no toxic effects to normal cell lines, but toxic action against HeLa tumor cells due promoting cell death by apoptosis. In addition, other pharmacological effects were observed, the PECC decreased nitric oxide (NO) production by activated macrophages, and prolonged blood clotting time through APTT assay. Then methanolic, ethanolic and ketone fractions were obtained from fractionation of PECC polysaccharides. Five methanolic fractions, six ethanolic fractions and two ketones were obtained; and all fractions were evaluated for antioxidant, cytotoxic, anticoagulant, immunomodulatory activities. E1.4 fraction exhibited significant metal chelating effect, a toxic action to induce apoptosis in HeLa cells, decreased NO production by activated macrophages, and extended blood clotting time. These results showed that the PECC pharmacological active polysaccharides would be present in the fraction E1.4. From fractionation of E1.4 polysaccharide six subfractions with different sizes were obtained: <3; 3-10; 10-30; 30-50; 50-100 and >100 KDa. About 80% of E1.4 polysaccharides had lower size to 10 KDa, and all the subfractions showed over 61% sugar in their chemical compositions. These subfractions exhibited different monosaccharide compositions, but xylose was presented in all of them. The subfractions exhibited distinct pharmacological effects in in vitro assays. Smaller subfractions (<30 KDa) had highest metal chelating activity and greater toxic action in tumor cells. The intermediate fractions (between 30-100 KDa) decreased more NO production of activated macrophages, for other side, the larger size (>100 KDa) modulated a greater number of inflammatory cytokines, and the had greatest anticoagulant effect. Therefore, when analyzing all the results together it is evident that the PECC pharmacological polysaccharides are heteroxylans, and were concentrated in E1.4 fraction, and heteroxilanas pharmacological effects depends on their molecular size. Thus, corncobs could be used as source from molecules with biotechnology potential

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In the shallow continental shelf in Northeastern Rio Grande do Norte - Brazil, important underwater geomorphological features can be found 6km from the coastline. They are coral reefs, locally known as “parrachos”. The present study aims to characterize and analyze the geomorphological feature as well as the ones of the benthic surface, and the distribution of biogenic sediments found in parrachos at Rio do Fogo and associated shallow platforms, by using remote sensing products and in situ data collections. This was made possible due to sedimentological, bathymetric and geomorphological maps elaborated from composite bands of images from the satellite sensors ETM+/Landsat-7, OLI/Landsat-8, MS/GeoEye and PAN/WordView-1, and analysis of bottom sediments samples. These maps were analyzed, integrally interpreted and validated in fieldwork, thus permitting the generation of a new geomorphological zoning of the shallow shelf in study and a geoenvironmental map of the Parrachos in Rio do Fogo. The images used were subject to Digital Image Processing techniques. All obtained data and information were stored in a Geographic Information System (GIS) and can become available to the scientific community. This shallow platform has a carbonate bottom composed mostly by algae. Collected and analyzed sediment samples can be classified as biogenic carbonatic sands, as they are composed 75% by calcareous algae, according to the found samples. The most abundant classes are green algae, red algae, nonbiogenic sediments (mineral grains), ancient algae and molluscs. At the parrachos the following was mapped: Barreta Channel, intertidal reefs, submerged reefs, the spur and grooves, the pools, the sandy bank, the bank of algae, sea grass, submerged roads and Rio do Fogo Channel. This work presents new information about geomorphology and evolution in the study area, and will be guiding future decision making in the handling and environmental management of the region

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The correct distance perception is important for executing various interactive tasks such as navigation, selection and manipulation. It is known, however, that, in general, there is a significant distance perception compression in virtual environments, mainly when using Head-Mounted Displays - HMDs. This perceived distance compression may bring various problems to the applications and even affect in a negative way the utility of those applications that depends on the correct judgment of distances. The scientific community, so far, have not been able to determine the causes of the distance perception compression in virtual environments. For this reason, it was the objective of this work to investigate, through experiments with users, the influence of both the field-of-view - FoV - and the distance estimation methods on this perceived compression. For that, an experimental comparison between the my3D device and a HMD, using 32 participants, seeking to find information on the causes of the compressed perception, was executed. The results showed that the my3D has inferior capabilities when compared to the HMD, resulting in worst estimations, on average, in both the tested estimation methods. The causes of that are believed to be the incorrect stimulus of the peripheral vision of the user, the smaller FoV and the smaller immersion sense, as described by the participants of the experiment.

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The reformist movements in the field of mental health have pointed battle flags, among which the prioritization of production of mental health care out of the asylum environment should be highlighted, aiming the reduction of psychiatric beds, greater control over the hospitalization, family co-participation and the rescue of the citizenship of the social players involved. With the progressive reduction of asylum beds, associated with a lot of structural problems in the health services, the occurrence of crises outside the hospital environment has been increasingly frequent, thus giving the family an important therapeutic role. In face of this scenario, there is an urgent need to understand the social construction of the care for psychiatric emergencies, identifying the meanings assigned by family members to their constituent aspects. This study seeks to answer the following research question: what are the social representations of family members about the care of psychiatric emergencies in the city of Mossoró, Rio Grande do Norte? Therefore, the aim is to analyze the social representations of family members about the care of psychiatric emergencies in the city of Mossoró, Rio Grande do Norte. This is an exploratory and descriptive study, with a mixed approach, making use of multimethods: for collection, the semi-structured interview and the Technique of Free Association of Words; for data analysis, the Thematic Analysis of Bardin and its steps was used, with the informational support of the softwares ALCESTE (Analyse Lexicale par Contexte d'un Ensemble de Segments de Texte) and Iramuteq (Interface de R pour les Analyses Multidimensionnelles de Textes et de Questionnaires); and the theoretical support of social representations. The study participants totaled 72, and they were selected from the following criteria: older than18 years, with degree of kinship with users suffering from some mental and behavioral disorder, and who have already witnessed a situation of crisis, rescued by the SAMU or other means and taken to the psychiatric hospital or general emergency room. Preliminary results point out: 1.Previous note of the research project with the aim to disseminate it in the scientific community and ensure the intellectual property of the work; 2.The contextual analysis of the care for emergencies in the study place. Reflection about the phenomenon provide a name to the care for the psychiatric emergencies, which is called immediate context; the technical and operational aspects that influence the care, as a specific/ general context; and mental health policies in Brazil are identified as metacontext; 3. The systematic review from randomized clinical trials in the databases PubMed, COCHRANE, LILACS, SciELO and SCIRUS, with the use of the descriptors: ‘Physical restraint’, ‘Psychiatric emergency services’, ‘Restraint’, ‘Physical and Emergency Services’, ‘Psychiatric’. Only one work met the search protocol criteria: a short-term essay that records limited results about the proportion of people who are in restraint and seclusion. It does not show statistically significant results in relation to indications, contraindications and risks of the use of physical restraint; 4. The social representations of the care for psychiatric emergencies. The study results point to the presence of five thematic categories: 1. feeling in the face of the crisis/care; 2. thoughts and perspectives about the crisis/care; 3. centrality of care in the medical- medication-hospitalization triad; 4. the thinking/acting in the face of the use of physical restraint and police force; 5. periodicity of crises. The central core of the representation is in the first category, whilst the peripheral elements are in the third and fifth categories. The contrast zone is in the second and fourth categories. The sadness is the most prominent element of the structure. The social representations about the care for psychiatric crises are at a time of transition between the hegemonic and reformist models, with the traditional aspects being predominant, but already showing peripheral and contrast elements that point to a possible change in the representational field.

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Although efficient from a technical point of view, mortar layers that make up the traditional masonry coating (slurry mortar, plaster and plaster) have to be in contradiction with the new construction technologies and more efficient methods of consumption and work rationalization. From an environmental point of view, the recovery of waste into new composites for the building has been a growing strand of studies in the scientific community, may prove to be a cost-effective solution in some cases. Thus, this research proposes the development of a mortar Decorative Coating Monolayer (RDM), for use in facades, produced on site, incorporating tempered glass waste (RVT) in the cement matrix, as a partial substitute for aggregate. Therefore, we adopted the binder respect / aggregate of 1: 6 (by volume), consistency index 250mm ± 20, sand substitution levels of glass waste 20%, 50% and 80% and relative water / cement varied in many traits. Two additives were used, a polymer, styrene-butadiene-based, and other chemical, besides mineral and silica fume inorganic pigment in colors red, yellow and blue. Mechanical tests were carried out on fresh pasta and hardened, as well as for the applied coating on masonry, so as to demonstrate the feasibility of the material. In addition, it verified the adequacy of the RDM built environment by means of thermal tests. The results demonstrated the feasibility of the proposed RDM with significantly higher values when compared to norms, especially the dash-added replacement content of 20% and addition of pigment in red. Therefore, the study shows the scientific community as an incentive to the use of technological innovations in construction, increasing the range of alternatives available for housing production, with the proposition of a material that achieves the desired functionality and obtain environmental gain, and may be adopted on construction sites as an alternative industrialized mortars.

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The spread of wireless networks and growing proliferation of mobile devices require the development of mobility control mechanisms to support the different demands of traffic in different network conditions. A major obstacle to developing this kind of technology is the complexity involved in handling all the information about the large number of Moving Objects (MO), as well as the entire signaling overhead required to manage these procedures in the network. Despite several initiatives have been proposed by the scientific community to address this issue they have not proved to be effective since they depend on the particular request of the MO that is responsible for triggering the mobility process. Moreover, they are often only guided by wireless medium statistics, such as Received Signal Strength Indicator (RSSI) of the candidate Point of Attachment (PoA). Thus, this work seeks to develop, evaluate and validate a sophisticated communication infrastructure for Wireless Networking for Moving Objects (WiNeMO) systems by making use of the flexibility provided by the Software-Defined Networking (SDN) paradigm, where network functions are easily and efficiently deployed by integrating OpenFlow and IEEE 802.21 standards. For purposes of benchmarking, the analysis was conducted in the control and data planes aspects, which demonstrate that the proposal significantly outperforms typical IPbased SDN and QoS-enabled capabilities, by allowing the network to handle the multimedia traffic with optimal Quality of Service (QoS) transport and acceptable Quality of Experience (QoE) over time.

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The urban expansion problem of Baía Formosa, a southern edge city of de Rio Grande do Norte eastern coast, which has been presented in other coast Brazilian towns, specially on those with tourist activities increase. Therefore, this situation brings huge concerns to their inhabitants, to their technical /scientific community and to the governments, because of the conflicts of interest and of the growth of urban problems that this has been created. At Baía Formosa, the situation is aggravated because the city is confined, once around it, there are large private proprieties, environmental preservation area and the sea, at the eastern edge. The objectives of this study are the analyses of this city expansion process in order to obtain adequate alternatives and defining methodology to apply in other urban nucleus that are subjected to similar situations. Of course, presents social relations, environmental conditions and promoting local population insertion should be considered in order that enjoin this process and contributing to a better social balance. This case study has used bibliography research, field data, maps and soil occupation recorders and photographs of the area, besides the primary data gathering by surveys carried out with many social actors. The present analysis shows that the urban expansion observed today is featured by a recent unsustainable model, which attacks the environment and brings either farm conflicts. On the other hand, the ecological tourism can represent an alternative in order to achieve an adequate expansion form, without forgetting the several structural parameters necessary to support the sustainable activities

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The production of waste from urban and industrial activities is one of the factors of environmental contamination and has aroused attention of the scientific community, in the sense of its reuse. On the other hand, the city of Salvador/Ba, with approximately 262 channels, responsible for storm water runoff, produces every year, by the intervention of cleaning and clearing channels, a significant volume of sediments (dredged mud), and thus an appropriate methodology for their final destination. This study aims to assess the influence of incorporation of these tailings in arrays of clay for production of interlocked block ceramic, also known as ceramic paver. All the raw materials from the metropolitan region of Salvador (RMS) were characterized by x-ray fluorescence, x-ray diffraction, thermal analysis (TG and TDA), particle size analysis and dilatometry. With the use of statistical experimental planning technique, ternary diagram was defined in the study region and the analyzed formulations. The specimens were prepared with dimensions of 60x20x5mm³, by uniaxial pressing of 30 MPa and after sintering at temperatures of 900°, 1000º and 1100ºC the technological properties were evaluated: linear shrinkage, water absorption, apparent porosity, apparent specifies mass, flexural rupture and module. For the uniaxial compression strength used cylindrical probe body with Ø 50 mm. The standard mass (MP) was prepared with 90% by weight of clay and 10% by weight of Channel sediment (SCP), not being verified significant variations in the properties of the final product. With the incorporation of 10% by weight of manganese residue (PFM) and 10% by weight of the Ceramic waste (RCB) in the mass default, in addition to adjusting the plasticity due to less waste clay content, provided increased linear firing shrinkage, due the significant concentration of K2O, forming liquid phase at low temperature, contributing to decreased porosity and mechanical resistance, being 92,5 MPa maximum compressive strength verified. After extract test leachate and soluble, the piece containing 10% of the PFM, was classified as non-hazardous and inert material according to NBR10004/04 ABNT. The results showed the feasibility on using waste, SCP, RCB and PFM clay mass, at temperatures above 900ºC, paver ceramic production, according to the specifications of the technical standards, so that to exceed the 10% of the PFM, it becomes imperative to conduct studies of environmental impacts