Utilização de resíduo lignocelulósico na obtenção de chapa de madeira aglomerada homogênea e compósito reforçado com fibra de vidro-E

This research is about the use of the coconut´s endocarp (nucifera linn) and the waste of derivatives of wood and furniture as raw material to technological use. In that sense, the lignocellulosic waste is used for manufacture of homogeneous wood sheet agglomerate (LHWS) and lignocellulosic load which take part of a polymeric composite with fiber glass E (GFRP-WC). In the manufacturing of the homogeneous wood sheet agglomerate (LHWS), it was used mamona´s resin as waste s agglutinating element. The plates were taken up in a hydraulic press engine, heated, with temperature control, where they were manufactured for different percentage of waste wood and coconuts nucífera linn. Physical tests were conducted to determine the absorption of water, density, damp grade (in two hours and twenty-four hours), swelling thickness (in two hours and twenty-four hours), and mechanical tests to evaluate the parallel tensile strength (internal stick) and bending and the static (steady) flexural. The physical test´s results indicate that the LHWS can be classified as bonded wood plate of high-density and with highly water resistant. In the mechanical tests it was possible to establish that LHWS presents different characteristics when submitted to uniaxial tensile and to the static (steady) flexural, since brittle and elasticity module had a variation according to the amount of dry endocarp used to manufacture each trace of LHWS. The GFRP-WC was industrially manufactured by a hand-lay-up process where the fiber glass E was used as reinforcement the lignocellulósic´s waste as load. The matrix was made with ortofitalic unsaturated polyester resin. Physical and mechanical tests were performed in presence of saturated humidity and dry. The results indicated good performance of the GFRP-WC, as traction as in flexion in three points. The presence of water influenced the modules obtained in the flexural and tensile but there were no significant alteration in the properties analyzed. As for the fracture, the analysis showed that the effects are more harmful in the presence of damp, under the action of loading tested, but despite this, the fracture was well defined starting in the external parts and spreading to the internal regions when one when it reaches the hybrid load

Efeito da adição do poli(etileno acrilato de metila) (ema) e da fibra de linter de algodão nas propriedades do poli(tereftalato de etileno) reciclado (petrec)

The development of new materials to fill the demand of technological advances is a challenge for many researchers around the world. Strategies such as making blends and composites are promising alternatives to produce materials with different properties from those found in conventional polymers. The objective of this study is to evaluate the effect of adding the copolymer poly(ethylene methyl acrylate) (EMA) and cotton linter fibers (LB) on the properties of recycled poly(ethylene terephthalate) (PETrec) by the development of PETrec/EMA blend and PETrec/EMA/LB blend composite. In order to improve the properties of these materials were added as compatibilizers: Ethylene - methyl acrylate - glycidyl methacrylate terpolymer (EMA-GMA) and maleic anhydride grafted polyethylene (PE-g-MA). The samples were produced using a single screw extruder and then injection molded. The obtained materials were characterized by thermogravimetry (TG), melt flow index (MFI) mensurements, torque rheometry, pycnometry to determinate the density, tensile testing and scanning electron microscopy (SEM). The rheological results showed that the addition of the EMA copolymer increased the viscosity of the blend and LB reduces the viscosity of the blend composite. SEM analysis of the binary blend showed poor interfacial adhesion between the PETrec matrix and the EMA dispersed phase, as well as the blend composite of PETrec/EMA/LB also observed low adhesion with the LB fiber. The tensile tests showed that the increase of EMA percentage decreased the tensile strength and the Young s modulus, also lower EMA percentage samples had increased the elongation at break. The blend composite showed an increase in the tensile strength and in the Young`s modulus, and a decrease in the elongation at break. The blend formulations with lower EMA percentages showed better mechanical properties that agree with the particle size analysis which showed that these formulations presented a smaller diameter of the dispersed phase. The blend composite mechanical tests showed that this material is stronger and stiffer than the blend PETrec/EMA, whose properties have been reduced due to the presence of EMA rubbery phase. The use of EMA-GMA was effective in reducing the particle size of the EMA dispersed phase in the PETrec/EMA blend and PE-g-MA showed evidences of reaction with LB and physical mixture with the EMA

Desenvolvimento de bioblendas poliméricas a partir de gelatina bovina e de tilápia com amido de milho

The natural raw materials acquired special importance beside the mineral raw materials with the need for using alternative sources to oil, because they can be used to produce biopolymers. Gelatin, produced from the denaturation of collagen, and starch, an abundant polysaccharide in various plants, are examples of biopolymers which have several technological applications, especially in films. The objective of this work is to produce polymeric bioblends with gelatin and corn starch using two types of gelatin: commercial bovine gelatin and gelatin produced from mechanically separated flesh of tilapia (Oreochromis niloticus). For the extraction of tilapia gelatin 3 distinct pretreatments, followed by extraction in distilled water under heating were performed. The properties of gelatin extracted were similar to bovine gelatin, and the differences can be explained by the difference in extraction processes and sources. Blends of commercial gelatin and starch were produced in an internal mixer from a Haake torque rheometer, to study the behavior of the gelatin mixture with starch, thus, the same compositions were processed by twin screw extrusion, to define the mixing parameters. Subsequently, the extrusion of blends of tilapia gelatin and corn starch was carried out in the same twin screw extruder. The physico-chemical, rheological and morphological properties of the blends with thermoplastic starch and gelatin were studied. It was found that various properties vary linearly with increasing concentration of the components. The blends produced are immiscible, and among the two gelatins, tilapia gelatin showed a better interfacial adhesion with the corn starch. Regarding the morphology, gelatins formed the dispersed phase in all compositions studied, even in compositions rich in starch. Can be concluded that the procedure for tilapia gelatin extraction is feasible and advantageous, and the increasing in its scale to a reactor of 30 liters is possible, with a satisfactory yield. The bioblends of bovine gelatin/corn starch and tilapia gelatin/corn starch were successfully produced, and the processing conditions were appropriate

Detecção de interface em tanques de petróleo usando transmissores de nível e controladores Fuzzy

This work presents a proposal to detect interface in atmospheric oil tanks by installing a differential pressure level transmitter to infer the oil-water interface. The main goal of this project is to maximize the quantity of free water that is delivered to the drainage line by controlling the interface. A Fuzzy Controller has been implemented by using the interface transmitter as the Process Variable. Two ladder routine was generated to perform the control. One routine was developed to calculate the error and error variation. The other was generate to develop the fuzzy controller itself. By using rules, the fuzzy controller uses these variables to set the output. The output is the position variation of the drainage valve. Although the ladder routine was implemented into an Allen Bradley PLC, Control Logix family it can be implemented into any brand of PLCs

Efeito antibacteriano de tecidos têxteis revestidos por prata através da técnica de deposição por plasma

In this study, it has been investigated the influence of silver film deposition onto 100% polyester woven and non-woven, on the survival of Escherichia coli and Staphylococcus aureus in contact with these surfaces. The treatment was performedin a chamber containing the working gas at low pressure (~ 10-2 mbar). Some process parameters such as as voltage: 470 V; pressure: 10-2 mbar; current : 0.40 A and gas flow: 6 and 10 cm3/min were kept constant. For the treatments with purêargon plasma using a flow of 6 and 10 cm3/min, different treatment times were evaluated, such as, 10 , 20, 30, 40, 50 and 60 minutes. Contact angle (sessile drop), measurements were used to determine the surface tension of the treated fabrics and its influence on the bacteria grow as weel as the possibilities of a biofilm formation. The formation of a silver film, as well as the amount of this element was verified byEDX technique. The topography was observed through scanning electron microscopy (SEM) to determine the size of silver grains formed on the surfaces of the fabric and assess homogeneity of treatment. The X-ray diffraction (XRD) was used to analyze the structure of silver film deposition. The woven fabric treatments enabled the formation of silver particulate films with particle size larger than the non-woven fabrics. With respect to bacterial growth, all fabrics were shown to be bactericidal for Staphylococcus aureus (S. aureus), while for the Escherichia coli (E. coli), the best results were found for the non-woven fabric (TNT) treated with a flow of 10 cm3/min to both bacteria

Adesão, proliferação e genotoxicidade celular de celulose bacteriana modificada por plasma

Bacterial cellulose (BC) has a wide range of potential applications, namely as temporary substitute skin in the treatment of skin wounds, such as burns, ulcers and grafts. Surface properties determine the functional response of cells, an important factor for the successful development of biomaterials. This work evaluates the influence of bacterial cellulose surface treatment by plasma (BCP) on the cellular behavior and its genotoxicity potential. The modified surface was produced by plasma discharge in N2 and O2 atmosphere, and the roughness produced by ion bombardment characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cell adhesion, viability and proliferation on BCP were analysed using crystal violet staining and the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium (MTT) method. Genotoxicity was evaluated using the comet and cytokinesis block micronucleus assay. The results show that the plasma treatment changed surface roughness, producing an ideal cell attachment, evidenced by more elongated cell morphology and improved proliferation. The excellent biocompatibility of BCP was confirmed by genotoxicity tests, which showed no significant DNA damage. The BCP has therefore great potential as a new artificial implant

Avaliação de efeitos biológicos de antiinflamatórios derivados do ácido propiônico através de modelos experimentais em nível molecular e celular

Derivatives of propionic acid NSAIDs are irreversible inhibitors of cyclooxygenase enzyme widely used. The aim of this study was to evaluate, through different experimental models, biological effects of derivatives of propionic acid (fenoprofen, naproxen, ibuprofen and ketoprofen) in cellular and molecular level. The labeling of blood constituents with technetium-99m (99mTc) and morphological analysis of erythrocytes of blood of rats, as well as growth, survival of cultures of Escherichia coli (E. coli) and the assessment of bacterial plasmid electrophoretic profiles were models used for experimental evaluation of possible biological effects of antiinflammatory drugs. The results show that, in general, anti-inflammatory drugs evaluated were not able to alter the labeling of blood constituents with 99mTc, the morphology of red blood cells from blood of rats, as well as the growth of cultures of E. coli and the electrophoretic profile of plasmid DNA. However, naproxen appears to cytotoxic effect on bacterial cultures, plasmids and genotoxic effects in reducing the action of stannous chloride in cultures of E. coli. The use of experimental fast performance and low cost was important for assessment of biological effects, contributing to a better understanding of the properties of propionic acid derivatives studied. anti-inflammatory, blood constituents, technetium-99m, stannous chloride, Escherichia coli; DNA

Resiliência e adesão ao tratamento em pacientes com lúpus eritematoso sistêmico

Universidade Federal do Rio Grande do Norte

Identificação e fatores de virulência de Candida spp isoladas da cavidade bucal de transplantados renais do hospital universitário Onofre Lopes em Natal-RN

Despite Candida species are often human commensals isolated from various oral sites such as: tongue, cheek and palatal mucosa plus subgingival region, there are some properties linked to the organism commonly known as virulence factors which confer them the ability to produce disease. Oral candidiasis is one of the main oral manifestations reported in literature related to kidney transplant patients. The objectives of the present study were to identify and investigate virulence factors of yeasts isolated from the oral cavity of kidney transplant recipients admitted at the Hospital Universitário Onofre Lopes, in Natal RN. Seventy Candida species isolated from 111 kidney transplant recipients were investigated in this study. Identification of the isolates was performed by using the evidence of germ tube formation, hypertonic broth, tolerance to grow at 42°C, micromorphology and biochemical profiles. We observed a high rate of isolation of yeasts from the oral cavity of kidney transplant recipients (63.1%) being C. albicans was the most prevalent species. Oral candidiasis was diagnosed in 14.4% of transplant recipients. We evaluated virulence properties of the isolates regarding to: biofilm formation on polystyrene microplates as well as XTT reduction, adherence to acrylic resin and human buccal epithelial cells and proteinase activity. Most isolates were able to form biofilm by the method of adhesion to polystyrene. All isolates of Candida spp. remained viable during biofilm formation when analyzed by the method of XTT reduction. The number of CFU attached to the acrylic resin suggested high adherence for C. parapsilosis. C. albicans isolates showed higher median adherence to human buccal epithelial cells than non-C. albicans Candida isolates. Nevertheless, this difference was not statistically significant. C. dubliniensis showed low ability to adhere to plastic and epithelial cells and biofilm formation. Proteolytic activity was observed for all the isolates investigated, including the unique isolate of C. dubliniensis. There was a statistically significant association between proteinase production and the presence of oral candidiasis. Studies related to oral candidiasis in renal transplant recipients are limited to clinical and epidemiological data, but investigations concerning Candida spp. virulence factor for this group of individuals are still scarce. We emphasize the importance of studies related to virulence factors of yeasts isolated from this population to contribute to the knowledge of microbiological aspects of oral candidiasis

Ethopoiésis e Heavy Metal: Subjetivação e consumo na cena de Natal-RN

Our research intends to comprehend the configuration of the resistance (Foucault) as the stylization of life in the contemporary world, taking Heavy Metal as the specific object of study. We believe that Heavy Metal is an ethopoietical device which admits practices of freedom withstanding the reified moral habits since the beginning of the socialization. This is reflected, mainly, in the creation of new individual and communal ways to stylize the life. We also suggest an expansion of Foucault s concept of resistance, considering the idea of consumer society described by Zygmunt Bauman. Our hypothesis understands that the contact with the underground of Heavy Metal provides new ethical manners (Foucault), where the individual take the Heavy Metal as a way of life. At this point, the consumption becomes a key-word since the participation in the underground of Heavy Metal is a way of consumption out of the rules of marketing a practice of freedom, a way of particular existence , being different in both mode and duration

Efeito da cloração da água de beber e do nível energético da ração sobre o ganho de peso e consumo de água em frangos de corte

Dois experimentos foram realizados com o objetivo de pesquisar o efeito da adição de cloro à água de beber e dos diferentes níveis de energia na ração sobre o ganho de peso e consumo de água em frangos de corte. No experimento 1, as aves foram alimentadas com dois níveis de energia metabolizável na ração (2900 e 3200 kcal EM/kg) em cada fase da criação. Foi observado que o nível energético não influi no consumo de água e no ganho de peso dos frangos de corte. No experimento 2, o nível de energia metabolizável da ração foi de 3200 kcal EM/kg e a água de beber foi clorada com hipoclorito de sódio a 11%, correspondendo a 5 ppm de cloro. O consumo de água foi menor nas aves que receberam água clorada. Apesar de o consumo de água ter sido menor, não houve redução no ganho de peso das aves que receberam hipoclorito de sódio. A adição de cloro à água de beber melhorou os índices bacteriológicos. Os resultados obtidos nestes experimentos evidenciam que os níveis energéticos das rações testadas não influenciaram o consumo de água dos frangos de corte; entretanto, a adição de cloro reduziu a ingestão de água, porém sem influir no ganho de peso nas aves tratadas.

Avaliação do nível de ruído em colhedoras combinadas

O presente trabalho teve o objetivo de determinar os níveis de pressão sonora nas cabines de colhedoras combinadas, por meio do uso de um medidor de nível de pressão sonora. Foram avaliadas as colhedoras New Holland TC-57, SLC 6200 e Massey Ferguson 3640, sendo determinado o nível de ruído na cabine do operador. O delineamento adotado foi o inteiramente casualizado, com 12 tratamentos e três repetições. Os resultados obtidos evidenciam que todas as colhedoras estudadas apresentaram ruído acima do nível máximo estabelecido pelas normas técnicas.

Da leitura da poesia à poesia da leitura: a contribuição da poesia para o Ensino Médio

La poésie occupe, à l école, une place réduite et, la plupart du temps, est reléguée à des dates commémoratives ou, quand utilisée, sert de pretexte à l étude de la grammaire et du vocabulaire. Cette thèse a comme objectif de réfléchir sur l importance de l enseignement de La littérature, et plus spécialement, celui de la poésie dans l enseignement secondaire. A comme principal objectif de montrer la place de la poésie dans l'enseignement secondairepour la formation socio-linguistique, cognitive et affective dês élèves. De plus, tente de démystifier l' idée qu'il est impossible de lire de La littérature et, en particuler, de la poésie, avec des adolescents.Il s agit de proposer des projets afin de travailler de manière adéquate la lecture de poésies en salle de classe par le biais de stratégies productives de lectures littéraires comme celles qui promeuvent la rencontre entre le lecteur et le texte. Pour cela, nous avons réalisé une expérience dans une école publique de l état Du Rio Grande do Norte, dans la commune de Natal, avec des élèves adolescents âgés de 14 à 18 ans. L' expérience a consisté en douze cours de lecture de poésies. Nous avons utilisé, comme instruments de collectes de données, des entrevues, des cahiers de classe et des questionnaires. Les références théoriques adoptées consistent en une bibliographie qui fait référence aux études d esthétique de La réception et de la coopération interprétative comme l ont formulées Jauss (1979), Iser (1996) et Eco (2002); la conception de lecteur et le processus de lecture selon Smith (1989); le socio-interactionnisme de Vigotski (1999; 2000); la médiation (lecture par degré ou scaffolding), de Graves et Graves (1995); la psychologie de l adolescence de Becker (1999), Carvajal (2001) e Gutierra(2003). Les résultats montrent l importance de la présence du médiateur dans La formation du lecteur, sachant qu en plus de contribuer et de potentialiser l intéraction entre le texte et le lecteur, l adhésion des élèves est améliorée. L expérience de vivre la poésie en salle de classe avec dês adolescents sujets de cette recherche, a prouvé qu il est possible, dans l enseignement secondaire, et malgré les difficultés, de réaliser um travail avec la poésie

Literatura e educação :ação argumentativa na discussão de histórias

The focus of this thesis is the discussion of stories from the fairy tales genre in reading classes of Children´s Literature. Its main purpose is to investigate the argumentative action in the mediation pedagogic process.The evidence from this study is that the argumentative action is a fundamental component of teacher´s mediation as far as story discussion is concerned. The concept of mediation in this thesis comes from principles of interacionist Psychology articulated with THE theory of argumentation. It is understood that argumentative action is a process that objectives to obtain and to intensify the interlocuter´s adhesion through speech. The analysis of the story discussion activity is based on Psycholinguistic, particularly on the study of prevision ability; on the Theory of reception with special reference to the theory of the aesthetic effect, which considers the reader´s reactions and reader´s replies to the text; and on sociocognitive conflict study highlighting conflicts modalities brought up by the discussion of texts. The corpus analysed is composed by discussion episodes of stories from reading classes of Children´s Literature realized through participative observation.The subjects were children aged five-six years old from a public pre-school located in Natal-RN, Brazil. The study highlights mediation acts of argumentative nature such as direct question; illustrations from the book; rereading that were used by the teacher-researcher in story discussion. Among its conclusions it is revealed that argumentative action in stories discussion favors and intensifies the agreement of children´s to the activity. It increases the interaction between text and reader; it favours children´s organization and explicitation of their thoughts. The analysed material shows children´s exposing their ability to argue when having adequade scaffolding by an argumentative mediator the teacher

Corpo e beleza: uma análise das produções da educação física, em nível de mestrado

Talking about body and beauty seems fairly familiar to physical education. We understand that the body language in the area provides many meanings over the appearance, beauty and aesthetics, thus requiring the need of criticism and the need to interrogate her to realize how physical education has been re-signified. For this purpose, considering the multiplicity of meanings that surround the body and beauty, we discussed the implications that this brings to the area of Physical Education, analyzing the conception of body and beauty in the studies in this area, at the masters level, from some questions: What conceptions of body and beauty have been discussed in the studies of physical education at the masters level? What is the relationship between the meanings of body and beauty products analyzed and identified in the models of beauty outlined in Physical Education? We understand the importance of this research and its contribution to the epistemological analysis of existing studies. And, mainly because there is a lack of studies that discuss these productions. For construction of this text and for our reflections, we rely on thoughts like David Le Breton, Claude Levi- Strauss, Michel Foucault, Maurice Merleau-Ponty, Ana Marcia Silva, Carmen Smith, Isabel Mendes, Karenin Porpino Nobrega and flounder. The present study is characterized as a qualitative research, and content analysis proposed by Laurence Bardin (1977) for data processing. The corpus was composed of eight essays in the area of Physical Education, published in the CAPES Theses Database for the period 2004 to 2008, selected from the subject and body beauty. The initial reading allowed us to select meaningful units and guide our discussions on two main themes, which make up the two chapters of the work. In the first chapter, entitled Body, beauty and culture, as evidenced understandings of body, nature and culture that are present in the work is considered. In the second chapter, Standard Body Transformations and beauty, we present the concepts of body and beauty found in the dissertation, focusing on the mutability of representations of the models of beauty in body singularities in the relations of power-knowledge and the importance given the body in society, especially with regard to physical education professionals. We have thus found that, considering the dissertations analyzed, the understanding of body and beauty has been resignified, when dealing with other aesthetic conceptions that consider the uniqueness expressed in the human body and the culture of which the individual belongs