Ecogenômica de archaea e monitoramento de comunidades de procariotos redutores de sulfato: aplicações na indústria de petróleo e gás

The human activities responsible for the ambient degradation in the modern world are diverse. The industrial activities are preponderant in the question of the impact consequences for brazilian ecosystems. Amongst the human activities, the petroliferous industry in operation in Potiguar Petroliferous Basin (PPB) displays the constant risk of ambient impacts in the integrant cities, not only for the human populations and the environment, but also it reaches the native microorganisms of Caatinga ground and in the mangrove sediment. Not hindering, the elaboration of strategies of bioremediation for impacted areas pass through the knowledge of microbiota and its relations with the environment. Moreover, in the microorganism groups associated to oil, are emphasized the sulfate-reducing prokaryotes (SRP) that, in its anaerobic metabolism, these organisms participate of the sulfate reduction, discharging H2S, causing ambient risks and causing the corrosion of surfaces, as pipelines and tanks, resulting in damages for the industry. Some ancestries of PRS integrate the Archaea domain, group of microorganisms whose sequenced genomes present predominance of extremophilic adaptations, including surrounding with oil presence. This work has two correlated objectives: i) the detection and monitoring of the gene dsrB, gift in sulfate-reducing prokaryotes, through DGGE analysis in samples of mDNA of a mangrove sediment and semiarid soil, both in the BPP; ii) to relate genomic characteristics to the ecological aspects of Archaea through in silico studies, standing out the importance to the oil and gas industry. The results of the first work suggest that the petrodegraders communities of SRP persist after the contamination with oil in mangrove sediment and in semiarid soil. Comparing the populations of both sites, it reveals that there are variations in the size and composition during one year of experiments. In the second work, functional and structural factors are the probable cause to the pressure in maintenance of the conservation of the sequences in the multiple copies of the 16S rDNA gene. Is verified also the discrepancy established between total content GC and content GC of the same gene. Such results relating ribosomal genes and the ambient factors are important for metagenomic evaluations using PCR-DGGE. The knowledge of microbiota associated to the oil can contribute for a better destination of resources by the petroliferous industry and the development of bioremediation strategies. Likewise, search to lead to the best agreement of the performance of native microbiota in biogeochemical cycles in Potiguar Petroliferous Basin ecosystem

A saúde psíquica de quem faz saúde: uma análise crítica sobre a humanização direcionada ao profissional de saúde

It is noticeable that pressure, tension and overwork are frequent in health professionals routine. The work related to the ward area demands deep attention and surveillance. Because of that, it is essential to have a specific look at the humanization directed at health professionals, considering that taking care of other human beings is the essence of their job. This study has analyzed the psychic health levels, as well as the stress health professionals are submitted to, providing a debate about the humanization in 06 public hospitals (03 of them awarded by actions of humanization, and 03 not awarded) in Rio Grande do Norte state, Brazil. A study with 126 active health professionals (doctors, nurses, psychologists, nutritionists and social workers) in ward areas in their respective institutions was carried out. The thesis presented, with multi-disciplinary characteristic, counted on the support of statisticians (to calculate samples and data analysis), psychologists, social workers and administrators (linked to the human resources sector in each hospital). A cross-sectional study was performed, taking into consideration both quantitative and qualitative factors. The tools used for that were a semistructured questionnaire with socio-demographic characteristics, work and humanization; Lipp's Stress Symptoms Inventory for Adults (ISSL), and the Goldberg s General Health Questionnaire (QSG). The workers are predominantly women (84,9%), married (54,8%), between 46 and 55 years old (40,5%), working in the same institution for more than 20 years (22,2%), and between 16 and 20 years (20,6%), respectively. They work 40 hours a week (71,4%) and have multiple jobs (61,9%). Although most of these individuals global psychic health is in a good level, there are a significant number of people that is gradually getting worse concerning psychic stress (F1) showed by QSG (54,7%), and stress showed by ISSL(42,1%). Observing the categories, nurses (41,5%). Nutritionists (20,8%), doctors and social workers (18,9%), were among the most affected. About general health (F6), 63% of the awarded hospitals and 70% of the not awarded ones, presented good health levels (ranging from 5 to 50%). It was also noticed that, in the groups mentioned above, 25 and 20% respectively, were inserted in scores between 55 to 90%, what means that they are in worsening phase. The fact that the hospital is awarded or well recognized doesn t interfere in health professionals stress level and in their psychic health. Through what was heard from these individuals, it was possible to verify that they know little about humanization, once few of them identify or know that the service they offer is in an adoption process by Ministerial Policies. It was also detected the necessity of developing actions aimed at worker s health. Such results showed the importance of have more investments in programs that are directed to workers well-being, because they deal with other people s health and it is known that it is difficult for them to offer high-quality assistance if there are not suitable physical, psychological and material conditions to help them develop their jobs. As a warning, it is fair to say that investments in actions that provide humanized care to health professionals, mainly concerning preventive care for their health and life quality in their work

Origem física das curvas sigmoidais respiratórias pressão-volume: recrutamento alveolar e elasticidade não-linear

An important unsolved problem in medical science concerns the physical origin of the sigmoidal shape of pressure volume curves of healthy (and some unhealthy) lungs. Such difficulties are expected because the lung, which is the most important structure in the respiratory system, is extremely complex. Its rheological properties are unknown and seem to depend on phenomena occurring from the alveolar scale up to the thoracic scale. Conventional wisdom holds that linear response, i.e., Hooke s law, together with alveolar overdistention, play a dominant role in respiration, but such assumptions cannot explainthe crucial empirical sigmoidal shape of the curves. In this doctorate thesis, we propose an alternative theory to solve this problem, based on the alveolar recruitment together with the nonlinear elasticity of the alveoli. This theory suggests that recruitment may be the predominant factor shaping these curves in the entire range of pressures normally employed in experiments. The proposed model correctly predicts the observed sigmoidal pressure volume curves, allowing us to discuss adequately the importance of this result, as well as its implications for medical practice

Estado nutricional antropométrico, composição corporal e pressão arterial em adolescentes

Os objetivos deste trabalho foram: (1) estimar as prevalências de excesso de peso e de gordura corporal, obesidade central e pressão arterial elevada (PAE) em adolescentes beneficiários do Programa Nacional de Alimentação Escolar (PNAE) da rede municipal de ensino de Natal-RN; (2) verificar a associação entre variáveis antropométricas e de composição corporal com a pressão arterial, a maturação sexual e a história familiar positiva de fatores de risco para doença cardiovascular (FRDCV); (3) comparar dois padrões de referência para classificação do excesso de peso em adolescentes; e (4) propor equações preditivas de massa gorda (MG) e massa livre de gordura (MLG) baseadas nos perímetros corporais. Trata-se de um estudo transversal, com 526 adolescentes beneficiários do PNAE, em Natal, Brasil. O tamanho da população de estudo foi definido por amostragem aleatória, em dois estágios, e ponderada segundo número de alunos de cada escola. No primeiro estudo, o excesso de peso foi determinado por Índice de Massa Corporal (IMC), a gordura corporal estimada por dobras cutâneas e a obesidade central por perímetro abdominal. A pressão arterial elevada foi classificada conforme a American Academy of Pediatrics. As prevalências foram apresentadas em valores relativos e efeito do desenho. Realizou-se uma análise fatorial para sintetizar o conjunto de variáveis antropométricas visando identificar fatores comuns. Extraíram-se dois fatores: (1) padrão excesso de adiposidade e (2) padrão adiposidade central elevada. Para avaliar a associação entre os padrões de adiposidade corporal com pressão arterial elevada, faixa etária, maturação sexual e história familiar de FRDCV utilizou-se a Razão de Chances e respectivo intervalo de confiança de 95% e regressão logística. No segundo estudo, calculou-se a sensibilidade e a especificidade do excesso de peso classificado segundo o IOTF e a World Health Organization WHO em relação ao excesso de adiposidade corporal; e a estatística Kappa para medir a concordância entre os dois padrões de referência. No terceiro estudo, foram elaborados modelos preditivos de MG e MLG com base em nove perímetros corporais, utilizando a bioimpedância Byodinamics 450 como padrão de referência. Para tanto foram selecionados 218 adolescentes eutróficos, segundo o IMC a partir do estudo transversal. As equações foram estimadas por regressão linear múltipla, considerando a idade e os perímetros corporais. Os resultados apontaram que 14,1% dos meninos e 15,7% das meninas tinham excesso de peso; 15,3% dos meninos e 11,6% das meninas tinham excesso de gordura corporal e dentre os meninos 14,3% tinham pressão arterial elevada e as meninas, 21,4%. Todos os efeitos do desenho foram inferiores a 2,5%. Nos meninos, o padrão excesso de adiposidade foi associado à história familiar positiva de FRDCV (ORajust=2,60; 1,09-6,22), maturação sexual (ORajust=2,92; 1,04-8,22) e PAE (ORajust=3,66; 1,34-9,94). Os meninos com 12 anos e mais apresentaram 6,1 vezes mais chance de apresentar padrão adiposidade central elevada do que os adolescentes com 10 a 11 anos (IC95% 2,32-16,04), assim como os púberes apresentaram 3,2 vezes este mesmo padrão em relação aos pré-púberes (IC95%1,14-8,85). A partir da comparação entre os dois padrões de referencia de classificação do excesso de peso por meio do IMC, observou-se que a sensibilidade foi de 79,3% para o critério IOTF e de 88,9% para WHO e a especificidade foi de 94,7% e 89,9%, respectivamente. O nível de concordância foi maior para o critério IOTF (Kappa=0,70 x Kappa=0,64). Em relação à construção das equações preditivas de gordura corporal, do total de 106 meninos e 112 meninas, foram desenvolvidas duas equações para estimar MG e duas para MLG, considerando o sexo. No sexo masculino, a equação para estimar a MG incluiu as variáveis idade, punho, quadril e perímetro abdominal (R2=0,552; AIC=416,04) e MLG, idade, punho e antebraço (R2=0,869; AIC=578,24). Enquanto que no feminino, MG foi estimada pelas variáveis punho, perímetro do abdômen, do quadril, da coxa proximal e da panturrilha (R2=0,838; AIC=415,36); e a MLG por idade, punho, perímetro do abdômen, do quadril e da panturrilha (R2=0,878; AIC=512,48). Conclui-se que os adolescentes tinham elevada prevalência de excesso de adiposidade corporal e de pressão arterial elevada. Tanto o padrão excesso de adiposidade quanto adiposidade central elevada constituem-se em padrões de risco. O padrão excesso de adiposidade foi associado à pressão arterial, história familiar positiva de FRDCV e maturação sexual em meninos. O critério IOTF mostrou-se menos sensível, mais específico, com maior nível de concordância e maior probabilidade de identificar corretamente o excesso de gordura corporal nos adolescentes avaliados. Quatro equações foram desenvolvidas para a estimativa da MG e MLG em adolescentes. As equações desenvolvidas para estimar a MG no sexo feminino e MLG para ambos os sexos apresentaram valores elevados de coeficiente de determinação ajustados e, portanto, são as preferenciais. Este estudo foi realizado com a participação de equipe multidisciplinar composta por professores da área de Nutrição, Endocrinologia Pediátrica, Estatística, Educação Física, discentes do Curso de Graduação em Nutrição e residentes em Pediatria

Associação da frequência alélica dos polimorfismos dos genes do sistema renina angiotensina com a força muscular e pressão arterial de idosas

Physiological changes induced by the aging process is dynamic and progressive, reducing the adaptability and independence of older people and may be influenced by genetic and environmental factors. Thus the aim of this thesis was to investigate the association between polymorphism of the ACE gene ID and the phenotypes of muscular strength and blood pressure of 62 elderly Brazilian (67.35 ± 5.66 years) during a 16-week program of supervised training. The elderly women were stratified by age, with the group 1 (G1, n = 34) <70 years and group 2 (G2 n = 28) ≥ 70 years, and in three groups by ACE, ACE-II (n = 8) ACE- DD (n = 35) and ACE-ID (n = 19). The level of muscle strength was evaluated by the method of maximum repetitions and measures of blood pressure (BP) were measured before and after training (PAPré1 and PAPós1) and before and after each training session (PAPre2 and PAPós2), in place of training. DNA samples were isolated from peripheral blood leukocytes polymorphism and insertion / deletion (ID) of the ACE gene (rs1800795) was genotyped by polymerase chain reaction (PCR) plus PCR-confirmatory. The genotype distribution of the polymorphism ID attended the prerogatives of Hardy-Weitíherg. There was variation in power levels before and after training and the age between groups (t-test) and the ACE polymorphism (ANOVA) (p <0.05). Depending on the results it was concluded that resistance training helps to reduce SBP and increased muscle strength of upper and lower limbs when considering the age and ACE polymorphism. In this study the Elderly carriers of the D allele were more reactive to changes in BP resistance training. This study was multidisciplinary project involving researchers in the areas Medical, Physical Education, Pharmacy, Nutrition, Gerontology and Statistics. This fulfilled the requirements of the multidisciplinary Graduate Program in Health Sciences

Tratamento de fístulas enterocutâneas através de sistema a vácuo com alta pressão e dieta oral normal

Enterocutaneous fistulas are associated with prolonged hospital stay, high morbidity/mortality, and increase in hospital costs. This study aims to describe the use of a vacuum system and normal oral diet in dealing with this problem. Methods: Seventy-four consecutive patients with recent and defined external postoperative fistulas were analyzed. Abdominal imaging was used to exclude abscess and distal obstruction. The fistula tract was sealed with Foley catheter, connected to a negative pressure flask, changed daily for 5, 10 or 15 days, as necessary. Normal oral diet was permitted. Results: No patient died. Serum albumin and transferrin showed significantly higher levels at the end of treatment than at the beginning. The moderate and low-output fistulas had the best results (97% closed). Forty-eight (65%) fistulas closed after five days, 16(22%) after 10 days and 4(5%) after 15 days. Treatment failed in 6(8%) patients, who subsequently underwent surgery. Only one patient with low-output did not close her fistula. The cost of the treatment was US$ 41.75/day and it was considered cost effective. Conclusions: The vacuum system demonstrated good results in the treatment of fistulas. It included simplicity, low cost, short hospital stay, absence of skin breakdown, normal eating, good nutrition and activity patterns

Assistência de enfermagem e o risco para úlceras de pressão medido pela Escala de Braden em unidade de terapia intensiva

The problem facing the incidence of pressure ulcers (UP) in the hospital environment especially in the intensive care unit (ICU), although it is an old and frequent event in our professional practice, it is not notified in the researches as much as it should be. We observed a tendency to invest in therapeutical and in studies about the production of sophisticated new bandages. Few, however, are the investments in research on preventive measures in order to prevent or at least slow down the development of lesions. In this sense, the study aimed to analyze the correlation between nursing care and the risk of developing UP measured by the Braden scale in ICU patients. This is a descriptive study of longitudinal quantitative approach. The project obtained a favourable opinion from the Ethics Committee of HUOL (no 486/10). Data collection was carried out in the Hospital of Unimed in Natal during six months in 2011. The sample was of 32 patients hospitalized in ICU for over four days. The results were processed in SPSS 15.0 for descriptive statistics and inferential statistics. We identified that, only 9.4% of our sample developed UP, being predominantly male, elderly people aged above 60 years, Caucasian, with diagnostic hypothesis at the time of hospitalization of sepsis, were clinical patients, who presented hemodynamic instability, using orotracheal tube (TOT), enteral probe (SNE), vesical probe delay (SVD) and had values of albumin and hemoglobin levels below normal. In addition, these patients had a longer hospital stay, longer usage of TOT, SNE, SVD, increased use of sedation and drain than those who did not develop UP and were all at risk for developing these injuries second Braden scores. 66.7% of the lesions developed were located in the sacral region, limiting the degree I and all patients that developed were considered serious, 100.0% of them have evolved since the death. Small were the differences between the averages of Braden scores between patients with and without UP, 11,9+2,4 against 12,4+2,6 with p = 0.627. The clinical aspects of the patients in the study were instrumental in the development of UP, once, these findings were statistically significant through the Mann-Whitney test, and appropriateness of nursing conduct was decisive for the prevention of pressure ulcers in critical patients, since many were those classified as at risk (28) and few who have developed lesions (03)

Validação de instrumentos para avaliação da habilidade e do conhecimento acerca da medida da pressão arterial

This study aimed to validate tools for evaluating the ability and knowledge about blood pressure (BP) among nursing students. It is a cross-sectional, descriptive, quantitative and methodological study accomplished at the Universidade Federal do Rio Grande do Norte (UFRN), Universidade do Estado do Rio Grande do Norte (UERN) and a private university of the state. The sample consisted of 27 judges of research selected from the inclusion criteria: nursing, teachers of the semiology and/or semiotics discipline, with at least 1 year of experience, being from UFRN, EEN, UERN and private university of the state and and agree to participate voluntarily with the signing of the consent form. The research was development in three stages: construction of two instruments based on the scientific literature, resulting in a structured checklist consists of 28 items and a knowledge questionnaire with 12 questions; submission of the instruments to the judges, in the period from June to September 2012, which should evaluate each item in appropriate , appropriate with changes and inappropriate , addition to making an overall assessment of each instrument based on 10 requirements; validation and verification to the level of agreement among the judges, through the application of Kappa and Content Validity Index (CVI). Was used the consensus level greater than 0.61 (good) to the Kappa index and greater than 0.75 for CVI. Was approved by the Ethics in Research / HUOL. After being coded and tabulated, the data were analyzed using descriptive statistics. Of the 27 judges who evaluated the instrument, 77.8% are female, with a mean age of 36.6 (± 9.0) years, 63.0% worked in UFRN, 74.1% had academic master and 63.0% worked exclusively on teaching. Average length of teaching experience was 7.9 (± 8.0) years and in the semiology and/or semiotics discipline of 5.5 (± 6.7) years. In the judgment of structured checklist and questionnaire of knowledge about blood pressure mensurement any item/question was considered inappropriate since all obtained level of agreement within the indices established (CVI> 0,75 E Kappa> 0.61). In relation to structured checklist, of those 28 items present, 9 showed perfect concordance index (CVI = 1.00, Kappa = 1.00) and another 19 were considered appropriate with changes, especially with regard to clarity and vocabulary. In the questionnaire of knowledge, among the 12 questions that comprised, 7 had perfect concordance index and the others were considered appropriate with changes as requirements as clarity, vocabulary, and feasible sequence of instructional topics. In terms of a overall evaluating of instruments, the structured checklist got CVI of 0.94 and Kappa of 0.89 and the knowledge questionnaire, CVI of 0.97 and a kappa of 0.94. Both instruments proved to be valid as to their content, configuring it as clear and objective tools of assessment of knowledge and ability on blood pressure, being of nursing students as well as others students and health professionals, since the use of valid measures seeking to reduce the risk of distorting the results

Úlceras de pressão: um estudo com pacientes de unidade de terapia intensiva

To characterize patients according to gender, age category, internment time, diagnostical hypothesis and location of the pressure ulcer; to identify the susceptibility conditions, intrinsical and extrinsical factors present on ICU patients and to verify on the existence of association between the susceptibility conditions and the intrinsecal and extrinsecal factors on the occurrence of PU. Methods: It is a descriptive study, of longitudinal design of the panel type, with quantitative approach, performed on two ICU s of a private hospital located in Natal/RN, with 40 patients interned at these units. The data collection was performed on all three shifts through a structured observation and physical exam of the patients' skin form seeking to identify the presence of PU. Results: The greatest occurence of PU was on individuals of the male gender (70%) when compared to the female gender (30%), that difference being statistically significant (p=0,0267), with the male gender presenting 4,3 times greater chance of developing PU than the female; the predominant age category was from 60 years of age on (85%), 60,0% presented 1 to 2 PU s after 7 (seven) days of permanence in the ICU s, the predominant diagnostical hypothesis on the patients with PU were the respiratory diseases (42,3%) and the most frequent locations of PU were the sacral region (40,0%) and heels (36,0%). 25 PU s of stage I were diagnosed on 50,0% of the followed patients, with general incidence of 50,0% on both ICUs. from the 88 variables researched, 75 were identified on the patients from the study, being the predominant conditions (anemia, hypotension, leukocytosis, other diseases hypertension blood pressure, cardiac insuffience, pneumonia - and ansiolythic), the intrinsecal factors (diminished muscular strenght and/or mass, discrete edema, totally compromised mobile coordination and total inability for movement on the bed) and the extrinsecal factors (inadequate mattress type, permanence on a single position for >2 hours, shearing/friction force, bed clothes with folds that leave marks on the body, pressure force) predominated on patients with PU. The male gender variables (p=0,0267,OR=4,3), sedation (p=0,0006,OR=4,1), psychomotive agitation (p=0,0375,OR=5,8) and leukocytosis (p=0,0285,OR=5,0) presented a significant statistical diference when analyzed independently. We verified an association of 17,3%, statistically significant (p=0,0384), between the susceptibility conditions (anemia, leukocytosis and hypotension), the intrinsecal factors (age equal or above 60 years, diminished/absent pain sensibility and smooth, fine or delicate skin) and the extrinsecal factors (inadequate mattress, pressure forces, shearing/friction force, permanence on a single position for more than 2 hours, elevation between 30 to 45 degrees and inadequate bed clothes' conditions), with a chance ratio of 4,6 times the risk of occurrence of PU on the patients that presented the referred association. Conclusion: The incidence of PU detected on the ICU-interned patients was high and we made evident the existence of association between the susceptibility conditions, the intrinsecal and extrinsecal factors on the occurrence of PU s on the ICUinterned patients, and thus we accept the alternative hypothesis proposed on the study

Proposta de algoritmo para detecção de vazamentos em oleodutos utilizando análise freqüencial de sinais de pressão

Pipeline leak detection is a matter of great interest for companies who transport petroleum and its derivatives, in face of rising exigencies of environmental policies in industrialized and industrializing countries. However, existing technologies are not yet fully consolidated and many studies have been accomplished in order to achieve better levels of sensitivity and reliability for pipeline leak detection in a wide range of flowing conditions. In this sense, this study presents the results obtained from frequency spectrum analysis of pressure signals from pipelines in several flowing conditions like normal flowing, leakages, pump switching, etc. The results show that is possible to distinguish between the frequency spectra of those different flowing conditions, allowing recognition and announce of liquid pipeline leakages from pressure monitoring. Based upon these results, a pipeline leak detection algorithm employing frequency analysis of pressure signals is proposed, along with a methodology for its tuning and calibration. The proposed algorithm and its tuning methodology are evaluated with data obtained from real leakages accomplished in pipelines transferring crude oil and water, in order to evaluate its sensitivity, reliability and applicability to different flowing conditions

Controlador preditivo generalizado multi-modelo aplicado ao controle de pressão arterial

Postsurgical complication of hypertension may occur in cardiac patients. To decrease the chances of complication it is necessary to reduce elevated blood pressure as soon as possible. Continuous infusion of vasodilator drugs, such as sodium nitroprusside (Nipride), would quickly lower the blood pressure in most patients. However, each patient has a different sensitivity to infusion of Nipride. The parameters and the time delays of the system are initially unknown. Moreover, the parameters of the transfer function associated with a particular patient are time varying. the objective of the study is to develop a procedure for blood pressure control i the presence of uncertainty of parameters and considerable time delays. So, a methodology was developed multi-model, and for each such model a Preditive Controller can be a priori designed. An adaptive mechanism is then needed for deciding which controller should be dominant for a given plant

Controle inteligente de pressão para uma rede sem reservatório de abastecimento urbano de água

The sanitation companies from Brazil has a great challenge for the XXI century: seek to mitigate the rate of physical waste (water, chemicals and electricity) and financial waste caused by inefficient operating systems drinking water supply, considering that currently we already face, in some cases, the scarcity of water resources. The supply systems are increasingly complex as they seek to minimize waste and at the same time better serve the growing number of users. However, this technological change is to reduce the complexity of the challenges posed by the need to include users with higher quality and efficiency in services. A major challenge for companies of water supplies is to provide a good quality service contemplating reducing expenditure on electricity. In this situation we developed a research by a method that seeks to control the pressure of the distribution systems that do not have the tank in your setup and the water comes out of the well directly to the distribution system. The method of pressure control (intelligent control) uses fuzzy logic to eliminate the waste of electricity and the leaks from the production of pumps that inject directly into the distribution system, which causes waste of energy when the consumption of households is reduced causing the saturation of the distribution system. This study was conducted at Green Club II condominium, located in the city of Parnamirim, state of Rio Grande do Norte, in order to study the pressure behavior of the output of the pump that injects water directly into the distribution system. The study was only possible because of the need we had to find a solution to some leaks in the existing distribution system and the extensions of the respective condominium residences, which sparked interest in developing a job in order to carry out the experiments contained in this research

Utilização de RNA´s na construção do diagrama de vida constante de probabilidade de materiais compósitos

The static and cyclic assays are common to test materials in structures.. For cycling assays to assess the fatigue behavior of the material and thereby obtain the S-N curves and these are used to construct the diagrams of living constant. However, these diagrams, when constructed with small amounts of S-N curves underestimate or overestimate the actual behavior of the composite, there is increasing need for more testing to obtain more accurate results. Therewith, , a way of reducing costs is the statistical analysis of the fatigue behavior. The aim of this research was evaluate the probabilistic fatigue behavior of composite materials. The research was conducted in three parts. The first part consists of associating the equation of probability Weilbull equations commonly used in modeling of composite materials S-N curve, namely the exponential equation and power law and their generalizations. The second part was used the results obtained by the equation which best represents the S-N curves of probability and trained a network to the modular 5% failure. In the third part, we carried out a comparative study of the results obtained using the nonlinear model by parts (PNL) with the results of a modular network architecture (MN) in the analysis of fatigue behavior. For this we used a database of ten materials obtained from the literature to assess the ability of generalization of the modular network as well as its robustness. From the results it was found that the power law of probability generalized probabilistic behavior better represents the fatigue and composites that although the generalization ability of the MN that was not robust training with 5% failure rate, but for values mean the MN showed more accurate results than the PNL model

Análise da magnetohidrodinâmica com transferência de calor em canais de placas paralelas via transformação integral

The main goal of the present work is related to the dynamics of the steady state, incompressible, laminar flow with heat transfer, of an electrically conducting and Newtonian fluid inside a flat parallel-plate channel under the action of an external and uniform magnetic field. For solution of the governing equations, written in the parabolic boundary layer and stream-function formulation, it was employed the hybrid, numericalanalytical, approach known as Generalized Integral Transform Technique (GITT). The flow is sustained by a pressure gradient and the magnetic field is applied in the direction normal to the flow and is assumed that normal magnetic field is kept uniform, remaining larger than any other fields generated in other directions. In order to evaluate the influence of the applied magnetic field on both entrance regions, thermal and hydrodynamic, for this forced convection problem, as well as for validating purposes of the adopted solution methodology, two kinds of channel entry conditions for the velocity field were used: an uniform and an non-MHD parabolic profile. On the other hand, for the thermal problem only an uniform temperature profile at the channel inlet was employed as boundary condition. Along the channel wall, plates are maintained at constant temperature, either equal to or different from each other. Results for the velocity and temperature fields as well as for the main related potentials are produced and compared, for validation purposes, to results reported on literature as function of the main dimensionless governing parameters as Reynolds and Hartman numbers, for typical situations. Finally, in order to illustrate the consistency of the integral transform method, convergence analyses are also effectuated and presented

Desenho e Construção de um protótipo gerador de jato de plasma frio a pressão atmosférica para aplicações biomédicas

Research for better performance materials in biomedical applications are constants. Thus recent studies aimed at the development of new techniques for modification of surfaces. The low pressure plasma has been highlighted for its versatility and for being environmentally friendly, achieving good results in the modification of physic chemical properties of materials. However, it is requires an expensive vacuum system and cannot able to generate superficial changes in specific regions. Furthermore, it is limits their use in polymeric materials and sensitive terms due to high process temperatures. Therefore, new techniques capable of generating cold plasma at atmospheric pressure (APPJ) were created. In order to perform surface treatments on biomaterials in specific regions was built a prototype capable of generating a cold plasma jet. The prototype plasma generator consists of a high voltage source, a support arm, sample port and a nozzle through which the ionized argon. The device was formed to a dielectric tube and two electrodes. This work was varied some parameters such as position between electrodes, voltage and electrical frequency to verify the behavior of glow discharges. The disc of titanium was polished and there was a surface modification. The power consumed, length, intensity and surface modifications of titanium were analyzed. The energy consumed during the discharges was observed by the Lissajous figure method. To check the length of the jets was realized with Image Pro Plus software. The modifications of the titanium surfaces were observed by optical microscopy (OM ) and atomic force microscopy (AFM ). The study showed that variations of the parameters such as voltage, frequency and geometric position between the electrodes influence the formation of the plasma jet. It was concluded that the plasma jet near room temperature and atmospheric pressure was able to cause modifications in titanium surface