Propagação de danos em sistemas cooperativos: propriedades termodinâmicas

High-precision calculations of the correlation functions and order parameters were performed in order to investigate the critical properties of several two-dimensional ferro- magnetic systems: (i) the q-state Potts model; (ii) the Ashkin-Teller isotropic model; (iii) the spin-1 Ising model. We deduced exact relations connecting specific damages (the difference between two microscopic configurations of a model) and the above mentioned thermodynamic quanti- ties which permit its numerical calculation, by computer simulation and using any ergodic dynamics. The results obtained (critical temperature and exponents) reproduced all the known values, with an agreement up to several significant figures; of particular relevance were the estimates along the Baxter critical line (Ashkin-Teller model) where the exponents have a continuous variation. We also showed that this approach is less sensitive to the finite-size effects than the standard Monte-Carlo method. This analysis shows that the present approach produces equal or more accurate results, as compared to the usual Monte Carlo simulation, and can be useful to investigate these models in circumstances for which their behavior is not yet fully understood

Influência do tratamento periodontal sobre os níveis da proteína c-reativa ultrassensível em pacientes com insuficiência renal crônica em fase de prétransplante

The present study evaluated the influence of non-surgical periodontal treatment on the levels of C- reactive protein (hsCRP) in patients with chronic renal failure (CRF) in pretransplant. We conducted a controlled and randomized trial to evaluate the periodontal condition and plasma concentrations of hsCRP, albumin and transferrin in 56 dialysis patients divided into two groups: experimental and control. The study was conducted at the dental clinic of Family and Community Health s Unit (USFC), located in Onofre Lopes University Hospital (HUOL), Federal University of Rio Grande do Norte (UFRN), from December 2010 to November 2011. Severe periodontitis was the type of periodontal disease more common, affecting 78.6% of patients. Periodontal conditions, evaluated through the means of probing depth, clinical attachment level, bleeding index and plaque index, proved to be uniform for both groups at the initial examination. There were no differences in levels of inflammatory markers between the two groups. The analysis of the concentrations of hsCRP allowed classifying study participants as at high risk of developing cardiovascular disease. After completion of periodontal treatment in the experimental group, there was a statistically significant reduction of the mean of all periodontal parameters assessed; however this improvement of periodontal health was not accompanied by changes in the levels of hsCRP, albumin and transferrin in the evaluation time. Given this, the periodontal treatment did not promote the reduction of systemic inflammatory burden and risk of cardiovascular complications in patients with CRF

Caracterização e aplicação de vermicultura natural e quimicamente modificada na adsorção de azul de metileno

Chemical modification of clays has been extremely studied in the search for improvements of their properties for use in various areas, such as in combating pollution by industrial effluents and dyes. In this work, the vermiculite was chemically modified in two ways, characterized and evaluated the adsorption of methylene blue dye. First was changed with the addition of a surfactant (hexadecyltrimethylammonium bromide, BHTA) making it an organophilic clay and then by adding an acid (HCl) by acid activation. Some analyzes were performed as X-ray fluorescence (FRX), X-ray diffraction (DRX), adsorption isotherms of methylene blue dye, infrared (FTIR) , scanning electron microscopy (SEM), thermal gravimetric analysis and spectroscopy energy dispersive (EDS). Analysis by FRX of natural vermiculite indicates that addition of silicon and aluminum, clay presents in its structure the magnesium, calcium and potassium with 16 % organic matter cations. The DRX analyzes indicated that the organic vermiculite was an insertion of the surfactant in the space between the lamellae, vermiculite and acid partial destruction of the structure with loss of crystallinity. The adsorption isotherms of methylene blue showed that there was a significant improvement in the removal of dye to the vermiculite with the addition of cationic surfactant hexadecyltrimethylammonium bromide and treatment with acid using HCl 2 mol/L. In acid vermiculites subsequently treated with surfactant, the adsorption capacity increased with respect to natural vermiculite, however was much lower compared vermiculite modified with acid and surfactant separately. Only the acidic vermiculite treated with surfactant adjusted to the Langmuir model. As in the infrared spectrometry proved the characteristics of natural vermiculite. In the organic vermiculite was observed the appearance of characteristic bands of CH3, CH2, and (CH3)4N. Already on acid vermiculite, it was realized a partial destruction with decreasing intensity of the characteristic band of vermiculite that is between 1074 and 952 cm-1. In the SEM analysis, it was observed that there was partial destruction to the acid treatment and a cluster is noted between the blades caused by the presence of the surfactant. The TG shows that the higher mass loss occurs at the beginning of the heating caused by the elimination of water absorbed on the surface between layers. In the organic vermiculite also observed a loss of mass between 150 and 300 °C caused decomposition of the alkylammonium molecules (surfactants)

Consumo c(l)iente: abordagem do gênero anúncio publicitário em livros didáticos de língua portuguesa do ensino médio

Portuguese language textbooks, according to what has been preconized on the official document to education, have been configured on discursive genres imported from diverse spheres of human activity. Adverts, genre of ample social circulation, spread from the Advertising sphere to the schools and started being approached by these collectaneas as an object and a tool for teaching. Therefore, this research deals with the approach of ads in Portugese textbooks. These discursive practices matter for the impact or appeal they exert over the (new) consumers, among which High School students; for their representation in the capitalist system, which guides us on our relationships and social practices; and for the mix of languages that end up at their composition, once they encapsulate the spirit of our time, par excellence, the one from the verbal-visual genres. To understand the treatment given to these advertising pieces, from questions/commentaries related to them, two collections were selected by the Programa Nacional do Livro Didático – Textbook National Program (PNLD 2012) among the ones more used by public High Schools in Natal/RN. From Applied Linguistics, from mestizo, nomadic and inter/transdisciplinary identity (MOITA LOPES, 2009), this study falls within the discursive chain of the interpretive tradition of historical-cultural approach (FREITAS, 2010) and names the Bakhtin Circle and its language‟s dialogical conception as inescapable partners. The data of the colletaneas show that the genre approach can happen as concrete utterance, as linguistic artifact and as hybrid, at work with questions and without questions, with the predominance of its occurrence in the portion of the volume devoted to the study of grammar. In the literature chapters and production/interpretation of compositions, it insert is incipient or it doesn‟t happen in the volume. Such a provision has implications for multiliteracies (ROJO, 2012) of the citizen student, once the lack or the abundance of critical reading proposals for this genre, that demand from the student the exercise of knowledge that is necessary to the construction of linguistic and social meanings, can be responsible for guide to a more conscious consumerism (material and cultural) by the chief customers of the work under review. The approaches of the genres seems to indicate a gradual transition that such material have undergone, which means, from the focus on clauses to the focus on utterances, or even the approach as linguistic artifact to hybrid and the concrete utterance, in search of overcoming the traditional tendency of taking advantage of formal aspects of the language, to the detriment of enunciative ones, and for coming into harmony with the guidelines and parameters of teaching in contemporary times, bringing the school duties close to the rights in life.

Sonho e cura: o culto de Asclépio em Epidauro entre os séculos IV e II a. C.

Profound changes have marked Greek society from the fourth century B.C.. Conquests, wars and epidemics altered drastically the Greek’s posture regarding his public life, his conception of gods and hence the construction of their spaces, whether sacred or profane. Through the fonts, we perceived that the cult of god Asklepeios turned very popular, in this context, for the peculiar way that the god relates to his devotees, through the dreams. We know that the dream was held, for the Greeks, as a space of real existence, it was sacred, and could be accessed in the healing rituals of Asklepios. Our work intends, thereby, to understand the curious and peculiar oniric space, mainly through the inscriptions, architectural structures of the sanctuary and the ancient texts that refer to the context of the period, because we understand that this space was the essential condition for the popularization of the cult, it placed the individual in direct contact with the divinity, a rare closeness between men and gods accepted by the greek imagery until then.

Desenvolvimento de novos biolubrificantes hidráulicos derivados dos óleos de maracujá e de moringa in natura e epoxidados

With the increasing environmental awareness, maximizing biodegradability and minimizing ecotoxicity is the main driving force for new technological developments. Thus, can be developed new biodegradable lubricants for use in environmentally sensitive areas. The aim of this study was to obtain new bio-lubricants from passion fruit (Passiflora edulis Sims f. flavicarpa Degener) and moringa (Moringa oleifera Lamarck) epoxidized oils and develop a new additive package using experimental design for their use as a hydraulic fluid. In the first stage of this work was performed the optimization of the epoxidation process of the oils using fractional experimental design 24-1 , varying the temperature, reaction time, ratio of formic acid and hydrogen peroxide. In the second step was investigated the selectivity, thermodynamics and kinetics of the reaction for obtaining the two epoxides at 30, 50 and 70 °C. The result of the experimental design confirmed that the epoxidation of passion fruit oil requires 2 hours of reaction, 50 °C and a ratio H2O2/C=C/HCOOH (1:1:1). For moringa oil were required 2 hours reaction, 50 °C and a ratio of H2O2/C=C/HCOOH (1:1:1.5). The results of the final conversions were equal to 83.09% (± 0.3) for passion fruit oil epoxide and 91.02 (±0,4) for moringa oil epoxide. Following was made the 23 factorial design to evaluate which are the best concentrations of corrosion inhibitor and anti-wear (IC), antioxidant (BHA) and extreme pressure (EP) additives. The bio-lubricants obtained in this step were characterized according to DIN 51524 (Part 2 HLP) and DIN 51517 (Part 3 CLP) standards. The epoxidation process of the oils was able to improve the oxidative stability and reduce the total acid number, when compared to the in natura oils. Moreover, the epoxidized oils best solubilized additives, resulting in increased performance as a lubricant. In terms of physicochemical performance, the best lubricant fluid was the epoxidized moringa oil with additives (EMO-ADI), followed by the epoxidized passion fruit oil with additives (EPF-ADI) and, finally, the passion fruit in natura oil without additives (PFO). Lastly, was made the investigation of the tribological behavior under conditions of boundary lubrication for these lubricants. The tribological performance of the developed lubricants was analyzed on a HFRR equipment (High Frequency Reciprocating Rig) and the coefficient of friction, which occurs during the contact and the formation of the lubricating film, was measured. The wear was evaluated through optical microscopy and scanning electron microscopy (SEM). The results showed that the addition of extreme pressure (EP) and anti-wear and corrosion inhibitor (CI) additives significantly improve the tribological properties of the fluids. In all assays, was formed a lubricating film that is responsible for reducing the coefficient of metal-to-metal wear. It was observed that the addition of EP and IC additives in the in natura vegetable oils of passion fruit and moringa did not favor a significant reduction in wear. The bio-lubricants developed from passion fruit and moringa oils modified via epoxidation presented satisfactory tribological properties and shown to be potential lubricants for replacement of commercial mineral-based fluids.

Características bioativas, funcionais e efeito protetor do resíduo desidratado de camu-camu (Myrciaria dubia H.B.K. (McVaugh)) sobre doenças degenerativas utilizando modelos in vivo C. elegans

Camu-camu (Myrciaria dubia H.B.K. (McVaugh)) is a native Amazon fruit, recognized worldwide as one of the main natural sources of ascorbic acid. Due to its great acidity, this fruit is generally consumed after processing into juice or as ingredient in food preparations. As a co-product of the camu-camu processing, a significant amount of agroindustrial residue is generated. Despite the studies showing the bioactive value and biological potential of the fruit, few studies have approached the possible processing techniques, transformation and preservation of camu-camu fruits and its agroindustrial pomace. Therefore, the present work has the objective of evaluating two different drying processes applied to camu-camu pomace (peel and seeds with residual pulp), freeze drying and hot air drying, in order to obtain a functional fruit product. This thesis was divided into three stages: the first one shows the studies related to the freeze drying and hot air drying, where we demonstrated the impact of the selected drying techniques on the bioactive components of camu-camu, taking the fresh pomace as the control group. Among the investigated conditions, the groups obtained at 50ºC and 4 m/s (SC50) and 80ºC and 6 m/s (SC80) were selected as for further studies, based on their ascorbic acid final content and Folin-Ciocalteau reducing capacity. In addition to SC50 and SC80, the fresh pomace (RF) and freeze dried (RL) samples were also evaluated in these further stages of the research. Overall, the results show higher bioactive concentration in the RF samples, followed by RL, SC50 and SC80. On the second step of the research, the antioxidant, antimicrobial and antienzymatic activities were evaluated and the same tendency was observed. It was also reported, for the first time in the literature, the presence of syringic acid in dried camu-camu pomace. In the third and final stage of the research, it was investigated the effect of dried camu-camu on aging and neuroprotective disorders, using the in vivo model C.elegans. It was observed that camu-camu extracts were able to modulate important signaling genes relevant to thermal and oxidative stresses (p < 0.05). The polar acid, polar basic and polar neutral fractions obtained from the low molecular extracts of SC50 were able to extend the lifespan of wild type N2 C. elegans in 20% and 13% (p < 0.001). Results also showed that the paralysis induced by the β1-42 amyloid was significantly (p < 0.0001) retarded in CL4176 worms. Similarly, the camu-camu extracts attenuated the dopaminergic induction associated to Parkinson’s disease. Finally, a global analysis of the data presented here reveal that the camu-camu pomace, a co-product obtained from the industrial processing of a native Brazilian fruit, is a relevant natural source of health relevant compounds. This thesis, shows for the first time, the multifunctionality of camu-camu pomace, a natural resource still underexploited for scientific, commercial and technological purposes.

Química em cena: uma proposta para formação inicial de professores de química

In educational observed difficulty in train teachers to meet the medium and higher education needs, and one reason for this is the different experiences in the training of educators in relation to those found in the classroom. So often arise criticisms related to relevance and efficiency of degree courses, as regards the performance of its natural mission, which weakens the teacher training. Thus, improving the quality of education is very dependent on the initiatives of teachers, creating teaching alternatives to strengthen their performance in school. From this reflection, it is concluded that teacher training needs new educational proposals that qualify, and so can promote the formation of his students more adequately. Among the educational proposals as alternatives to initial teacher training may use the scientific theater (TC). Considering this possibility, this work has been proposed as investigate and discuss the influence of TC combined with experimentation in the initial training of future teachers in Chemistry who participate in the Groups Fanatics chemistry Theatre (UERN) and Chemistry on Stage (UFRN). Therefore, there was, in a first stage, theatrical essays based on the theater of the oppressed, and written dramaturgical scripts, a collaborative proposal. To incorporate experimentation in chemistry to theater rehearsals, there was a systematic literature search and after content analysis, were selected categories, materials and reagents easily accessible, easy procedures and implementation with low risk of accidents and easy care chemical waste. In the second part we identified: a) the beliefs of student teachers in the use of TC ally trial for initial training of chemistry teachers; b) the influence of TC ally to trial on learning of chemical concepts of high school students who attended the shows; c) the reasons for using or not TC ally to trial by chemistry teachers who participated in the TC group and currently work in the classroom. In this study, questionnaires and interviews were used, compounds, respectively, by a Likert scale and open questions. Quantitative data were analyzed by classical statistics the media, using as centrality measures the average, the concordance argument and the average deviation. Qualitative data were discussed according to content analysis, with categories that emerged from reading the answers. These analyzes concluded that the licensees have a positive view on the use of scientific theater for disclosure of the chemical for use in the learning of chemical concepts, pedagogical and disciplinary knowledge, and to form promotion strategy for research and extension at the University. They credit improvements in their initial training on the use of scientific theater combined with experimentation. The TC provides motivation for the construction of conceptual thinking in an informal way of chemical communication, allowing the student to expand their knowledge, not only favoring the phenomenological approach, but also the construction of chemical knowledge and the internalization of scientific concepts.

Translocação bacteriana para o pulmão na icterícia obstrutiva experimental em ratos

RESUMO: Objetivo: Tem sido demonstrado que a icterícia obstrutiva provoca depressão do sistema imunológico, mudança no padrão de colonização bacteriana dos intestinos e passagem de bactérias da luz intestinal para a circulação porta e sistêmica. Estudo experimental em ratos procurou observar a possibilidade de translocação bacteriana para os pulmões após a ligadura do colédoco. Método: Foram utilizados 20 ratos Wistar pesando de 178 a 215g, separados aleatoriamente em dois grupos iguais. Nos ratos do grupo I foi feita a ligadura do colédoco e nos do grupo II apenas a manipulação do colédoco com pinça atraumática (sham operation). No sétimo dia de observação os animais foram mortos com superdose de anestésico, sangue foi colhido para dosagem de bilirrubinas e os pulmões ressecados sob condições assépticas. Metade de cada pulmão foi homogeneizada e semeada em meios de cultura ágar McConkey e ágar sangue. A outra metade serviu para exame histopatológico –coloração hematoxilina e eosina. Os dados foram analisados pelo teste t, com significância 0,05. Resultados: revelaram bilirrubina total em média 18,7±3,6 no grupo I e 0,7±0,2 no grupo II. No grupo I foram isoladas colônias de Klebsiela sp nos pulmões de 30% dos animais e E. coli em 20%, e os escores histopatológicos atingiram a média 6,2±2,08. No grupo II não foram detectadas bactérias nos pulmões e os escores do exame histopatológico atingiram 1,8±1,16. A diferença dos dados analisados mostrou-se significativa (p<0,05). Conclusões: Concluiu-se que a icterícia obstrutiva por ligadura do colédoco em ratos provocou translocação de germes Gram-negativos para os pulmões e resultou em alterações histopatológicas significativas.

Repercussões do tempo operatório em pulmões de ratos idosos

A duração das operações pode representar um fator importante para uma série de complicações pós-operatórias, especialmente para os indivíduos idosos. Objetivo: estudar a repercussão nos pulmões, de operações de diferentes tempos de duração. Métodos: Vinte ratos idosos (18 meses) e 20 jovens (3 meses) foram separados aleatoriamente em grupos A e B respectivamente. Os grupos foram divididos em A1, A2, A3, A4, B1, B2, B3 and B4, com cinco ratos cada. Os animais foram anestesiados com pentobarbital (20mg/Kg) intraperitoneal. No subgrupo A1 e B1 foi feita operação com duração de 30 minutos, nos grupos A2 and B2 60 minutos, em A3 and B3 a operação foi feita em 120 minuto e os animais A4 e B4 (controle) não foram operados. O procedimento consistiu de laparotomia xifopubiana que foi aberta e fechada tantas vezes quanto necessário para atingir os tempos estipulados. Após o quinto dia pós-operatório os animais foram mortos com superdose de anestésico e biópsias de ambos os pulmões foram realizadas. Os achados histopatológicos foram transformados em escores. Resultados: os grupos de ratos jovens atingiram os escores: A1= escore 6, A2=11; A3=28; A4=5. Os ratos idosos tiveram os escores: B1=12; B2=34; B3=51 e B4=6. A análise estatística revelou diferenças significantes entre os escores dos grupos A e B. Conclusões: O tempo prolongado nas operações realizadas em ratos idosos contribuiu para o aparecimento de alterações pulmonares de modo significante. Quanto maior o tempo operatório, mais intensas e mais freqüentes as complicações pulmonares

Infecção hospitalar em pacientes cirúrgicos de hospital universitário

Analisar fatores intercorrentes e a incidência da infecção em pacientes operados no Hospital Universitário da UFRN. Métodos: Foram estudados, através de protocolo previamente estabelecido, 3.120 pacientes internados que se submeteram a procedimentos cirúrgicos no período de janeiro de 1999 a outubro de 2002. Resultados: O índice de infecção hospitalar foi de 5,9%, e a topografia de maior incidência foi a ferida operatória (3,7%). Infecção respiratória ocorreu em 1,2%, urinária em 0,6% e bacteremia em 0,1%. O índice de infecção comunitária foi de 9,2%, predominando infecção urinária (5%) e respiratória (2,1%). Quanto ao grau de contaminação das feridas operatórias, as feridas limpas (1479) apresentaram infecção em 2,9%, as feridas limpascontaminadas (1277) em 6,0% dos casos, as feridas contaminadas (270) em 15,1%, e as ferida infectadas (94) resultaram em infecção em 30,75% dos casos. Conclusão: Concluiu-se que a incidência de infecção cirúrgica foi compatível com os índices na literatura mundial. A partir desses dados, ratifica-se a importância de medidas de controle de infecção hospitalar de forma sistemática, como vem sendo realizado no hospital onde o estudo foi realizado