RESUMO Os fenômenos que envolvem a dinâmica de gases rarefeitos para fluxo de gases em micro-canais têm sido fonte de estudo em várias pesquisas. A Equação de Boltzmann descreve tais fenômenos sendo que a partir da sua simplificação surge a teoria cinética para a dinâmica dos gases rarefeitos. Os modelos cinéticos apresentam resultados sólidos e é abordado, neste estudo, em uma versão analítica através do método de ordenadas discretas. Dessa maneira, exploramos um modelo mais próximo da realidade, comparando os valores numéricos gerados por quatro modelos cinéticos derivados de maneira unificada da Equação Linearizada de Boltzmann. Em termos de viscosidade e condutividade térmica os modelos são confrontados baseados na estatística não paramétrica para problemas da dinâmica de gases rarefeitos resultantes do movimento de transferência de massa. Além disso, utiliza-se a interação gás-superfície definida pelo núcleo de Cercignani-Lampis ao longo de um canal para placas heterogêneas.

ABSTRACT The phenomena that involve the rarefied gas dynamics for gas flow in micro-channels have been a source of study in several studies. The Boltzmann Equation describes such phenomena, and from its simplification comes the kinetic theory for the dynamics of rarefied gases. The kinetic models present reliable results and are analyzed in this study under an analytical version using the discrete ordinate method. Therefore, we explore a model closer to reality, comparing the numerical values generated by four kinetic models derived in a unified way from Boltzmann’s Linearized Equation. In terms of viscosity and thermal conductivity, the models are compared based on non-parametric statistics for problems with rarefied gas dynamics resulting from the mass transfer movement. Also, the gas-surface interaction defined by the Cercignani-Lampis nucleus along a channel for heterogeneous plates is used.

Abstract Objective: The aim of this study was to compare the differences in the levels of physical activity practiced during the weekdays and weekends in obese postmenopausal women. Method: 117 post-menopausal women aged between 50 and 79 were evaluated. To estimate the percentage of body fat the Dual-Energy X-ray Absorptiometry was used. The assessment of physical activity level was obtained using a tri-axial accelerometer. Results: There was a significant increase in physical activity-light and a significant decrease in physical activity moderate, vigorous, moderate-vigorous and overall number of counts at the weekend compared to the weekdays. The physical activity moderate-vigorous reduced by an average of 38.6% (p < 0.001) at the weekend compared to the weekdays. Conclusion: Obese post-menopausal women presented decreasing physical activity moderate, vigorous, moderate-vigorous and overall number of counts at the weekends compared to the weekdays and an increase in physical activity light.

Resumo Objetivo: Comparar as diferenças nos níveis de atividade física feitas durante a semana e fins de semana em mulheres pós-menopáusicas com obesidade. Método: Foram avaliadas 117 mulheres na pós-menopausa com idade entre 50 e 79 anos. Para o cálculo do percentual de gordura corporal foi utilizado raios-X absorciometria de dupla energia. Se obteve a evolução do nível de atividade física por um acelerómetro triaxial. Resultados: Houve um aumento significativo na atividade física leve e uma diminuição significativa na atividade física moderada, vigorosa, moderada a vigorosa e o número total de contagens no fim de semana em comparação com a semana. Atividade física moderada a vigorosa foi reduzida por uma média de 38.6% (p < 0.001) no fim de semana em comparação com a semana. Conclusão: As mulheres obesas na pós menopausa apresentaram uma diminuição da atividade física moderada, vigorosa, moderada a vigorosa e o no número total de contagens nos fins de semana em comparação com a semana e aumento da atividade física suave.

Resumen Objetivo: Comparar las diferencias en los niveles de actividad física practicada durante los días de semana y fines de semana en las mujeres obesas posmenopáusicas. Método: Se evaluaron 117 mujeres post-menopáusicas de edades comprendidas entre 50 y 79 años. Para calcular el porcentaje de grasa corporal se utilizó la absorciometría de rayos X de doble energía. Se obtuvo la evaluación del nivel de actividad física mediante un acelerómetro triaxial. Resultados: Hubo un aumento significativo en la actividad física suave y una disminución significativa en la actividad física moderada, vigorosa, moderada-vigorosa y el número total de recuentos en el fin de semana en comparación con los días de la semana. La actividad física moderada-vigorosa se redujo en un promedio del 38.6% (p < 0.001) en el fin de semana en comparación con los días de la semana. Conclusión: Las mujeres obesas posmenopáusicas presentaron disminución de la actividad física moderada, vigorosa, moderada-vigorosa y el número total de recuentos en los fines de semana en comparación con los días de la semana y un aumento de actividad física suave.

Pancreatoduodenectomy continues to have a high rate of complications. The most common and severe complications are intra or postoperative bleeding, pancreatic fistulae and derangements of gastric emptying. Each of these requires a great deal of clinical suspicion and an multidisciplinary management. This is a review of these complications, their clinical manifestations and their management.

A pesar de Ia disminución observada en Ias cifras de mortalidad de Ia pancreatoduodenectomía, continúa siendo una intervención asociada a una alta tasa de complicaciones. Las más comunes y asociadas a una mayor morbimortalidad son: el sangrado intra y post operatorio, Ia fístula pancreática y trastornos asociados al vaciamiento gástrico. Cada una de Ios eventos anteriores, requiere de un alto grado de sospecha clínica y de un manejo de tipo multidisciplinario. En este reporte se analizan Ias complicaciones anteriormente descritas, sus manifestaciones clínicas y Ios principios de su manejo.

Background: Sleeve gastrectomy is replacing gastric banding in the management of morbid obesity. Aim: To report the results of sleeve gastrectomy performed simultaneously with the extraction of a gastric band. Material and Methods: We report ten patients aged 34 to 53 years (nine women) operated between 2008 and 2009. Results: The main indication for sleeve gastrectomy was the failure of the gastric band. No complications were recorded and patients were discharged 72 hours after the procedure. Conclusions: Sleeve gastrectomy can be carried out simultaneously with the extraction of a gastric band, without increasing operative complications.

Introducción: La Gastrectomía Vertical ha reemplazado a la banda gástrica en el manejo de un importante número de pacientes portadores de obesidad. El objetivo de este trabajo es mostrar los resultados de una serie de pacientes, en los que se realizó una Gastrectomía Vertical posterior a la extracción de una banda gástrica en un mismo tiempo operatorio. Método: La serie incluye a 10 pacientes operados entre Mayo de 2008 y Noviembre de 2009. La principal indicación de la Gastrectomía Vertical fue el fracaso de la banda como tratamiento de la obesidad. Resultados: En los 10 pacientes estudiados, la gastrectomía se pudo efectuar sin mayores dificultades ni diferencias con respecto al procedimiento habitual. No existieron complicaciones post operatorias, siendo la totalidad de los pacientes dados de alta dentro de las 72 horas. Conclusión: La Gastrectomía Vertical representa una alternativa de manejo en pacientes portadores de una banda gástrica con indicación de extracción de esta, ya sea por fracaso o por síntomas asociados a su presencia. El procedimiento puede efectuarse de manera segura en el mismo acto operatorio y sus resultados son comparables a los observados cuando la técnica se efectúa en pacientes que no han sido intervenidos previamente.

Single photon emission computed tomography and computed tomography (SPECT/CT), integrates a gamma camera and a CT scan and is effective for the location of parathyroid adenomas. We report a 55 years old male and a 80 years old female with primary hyperparathyroidism. In both cases the 99mTc-Sestamibi parathyroid scintigraphy detected a functioning nodule whose presence was confirmed with SPECT/CT.

El SPECT/CT integra una gamacámara y un escáner radiológico en un solo equipo híbrido que fusiona la imagen de la cintigrafía SPECT (tomografía computada de fotón único) con la imagen morfológica obtenida con un escáner de baja intensidad, sin movilizar al paciente, en una perfecta correspondencia anátomo-funcional, permitiendo identificar con exactitud la localización de un adenoma paratiroideo. Se describen dos pacientes con hiperparatiroidismo primario, con ecotomografía convencional negativa, donde el SPECT/CT demostró la localización exacta de adenomas de ubicación no habitual.

Background: Autoimmune pancreatitis is a special form of chronic pancreatitis, more common in men and usually presenting as obstructive jaundice or abdominal pain. It may be associated with other immunological disorders and sometimes it is possible to find positive serological markers. Typical images show pancreatic enlargement with focal or diffuse stenosis of the pancreatic duct but sometimes it presents as a focal pancreatic mass that is difficult to differentiate from pancreatic carcinoma. Aim: To report ten cases of autoimmune pancreatitis. Material and Methods: Retrospective review of clinical records of 10 patients aged 26 to 56 years (six males) with autoimmune pancreatitis. Results: The clinical presentation was obstructive jaundice in six cases, acute pancreatitis in two, persistent increase in serum amylase and Upase in one, and permanent abdominal pain and weight loss in one. On imaging studies, a circumscribed mass was founded in six patients. An endoscopic retrograde colangiopancreatography was performed in four patients showing an abnormal pancreatic duct in all. Six patients were operated and tissue for pathological study was obtained in five, showing inflammatory infiltration. Vive patients were treated with steroids with a good clinical response. Conclusions: Autoimmune pancreatitis must be borne in mind in the differential diagnosis of pancreatic lesions.

Este trabalho teve por objetivo avaliar a atividade residual da mistura formulada dos herbicidas (imazethapyr+imazapic), marca comercial Only, para a cultura do sorgo granífero, cv. BR 304, semeado em rotação, após um, dois e três anos com arroz irrigado, no sistema de produção Clearfield® (CL). Os experimentos foram conduzidos em campo, em área da Universidade Federal de Pelotas, município de Capão do Leão-RS. Considerou-se o arroz como a cultura principal, o azevém como cultura sucessora e o sorgo como substituinte do arroz no sistema de rotação. À exceção da primeira semeadura de arroz, em cada ano, todas as culturas foram conduzidas pelo sistema direto. O delineamento experimental foi o de blocos ao acaso, com quatro repetições. Os tratamentos foram arranjados em esquema fatorial, em que o fator A comparou resíduo em diferentes ambientes (anos de cultivo de arroz CL) e o B avaliou o efeito de doses sobre o residual dos herbicidas. O arroz semeado foi o cv. IRGA 422 CL, e os tratamentos herbicidas foram doses da mistura formulada de (imazethapyr+imazapic) a 0, (75+25), (112,5+37,5) e (150+50) g ha-1, acrescidos de Dash a 0,5% v/v. Os experimentos ou ambientes foram denominados de A1, A2 e A3, respectivamente para um, dois e três anos de cultivo de arroz irrigado pelo sistema CL. Como espécie indicadora da presença de resíduos dos herbicidas utilizou-se o sorgo granífero, cv. BR 304. As variáveisresposta consideradas foram: população e estatura média das plantas, rendimento biológico, peso de mil grãos e produtividade do sorgo. Quanto a estatura de plantas e peso de mil grãos, ocorreu interação entre os fatores ambiente e dose dos herbicidas; já para as demais variáveis verificou-se significância estatística somente para doses dos herbicidas. Concluise que o cultivo de arroz irrigado no sistema de produção CL deixa resíduos dos herbicidas (imazethapyr+imazapic) no solo, capazes de causar danos irrecuperáveis ao sorgo cultivado em safra subsequente ao arroz.

The objective of this research was to evaluate the field persistence of the herbicide Only (imazethapyr+imazapic), to grain sorghum, planted in rotation after one, two or three years of Clearfield® (CL) rice. The field study was carried out at Universidade Federal de Pelotas, Capão do Leão, state of Rio Grande do Sul. Clearfield rice was established as the main crop, Italian ryegrass as a succession crop and grain sorghum, as a rotation crop after CL rice. Except for the first rice crop, all the other cultures were planted as no-till rice. Ryegrass plants were burned down in every experiment using glyphosate (760 g a.e. ha-1). The experimental design was a factorial with treatments arranged in a complete randomized design, with four replications, where factor A was the number of CL rice seasons and B was the herbicide rate. The rice cultivar was IRGA 422 CL, and the herbicide treatments were Only (imazethapyr+imazapic) at 0; (75+25); (112.5+37.5) and (150+50) g ha-1. Adjuvant Dash was added to the herbicide at 0.5% v/v. The experiments were labeled as A1, A2 or A3, respectively, for one, two or three years of CL rice. Grain sorghum, cv. BR 304, was planted as a bioindicator of herbicide residue. The following parameters were evaluated: plant population, plant height; above ground biomass, 1000-grain weight and grain yield. As for grain sorghum plant height and 1000-seed weight, an interaction was observed between the different environments (years of CL rice) and herbicide rate (imazethapyr+imazapic). For the other parameters, only effect for herbicide rat was detected. The results suggested that all grain sorghum parameters were affected by the herbicides (imazethapyr+ imazapic) in the soil. Grain sorghum injury increased with herbicide rate. In conclusion, grain sorghum, planted in rotation with rice is affected by the residue of the herbicide Only (imazethapyr+imazapic) applied to Clearfield® rice.

The objective of this research was to improve Glucose-6-phosphate dehydrogenase (G6PD) production by Saccharomyces cerevisiae W303-181, which carry the plasmid YEpPGK-G6PD, by varying the following cultivation conditions: pH value (4.8, 5.7 and 6.6); inoculum concentration (0.1, 0.6 and 1.1 g/L) and initial glucose concentration (20.0, 30.0 and 40.0 g/L). The effect of those variables on G6PD production capability was studied by the application of response surface statistical analysis. The results showed that the highest G6PD production (1594.2 U/L), specific activity (1189.7 U/g cell) and productivity (45.6 U/L.h) occurred at pH 4.8, inoculum concentration of 0.1 g/L and initial glucose concentration of 20.0 g/L, under agitation of 150 rpm at 30ºC after 36 h. In this work, the strain expressed about 21 fold more activity than the wild S. cerevisiae strain, being an attractive and promising new source of this enzyme.

Este trabalho teve por objetivo avaliar a atividade residual da mistura comercial (imazethapyr+imazapic) sobre azevém semeado em sucessão em áreas antes cultivadas com arroz Clearfield® (CL) por um, dois ou três anos consecutivos. Os experimentos foram conduzidos em campo, no município de Capão do Leão, RS. O arroz cv. IRGA 422 CL foi considerado cultura principal, e o azevém, variedade indefinida, cultura sucessora. O delineamento experimental utilizado foi o de blocos ao acaso, com quatro repetições. Os tratamentos foram arranjados em esquema fatorial, em que o fator A, dentro da mesma safra, comparou resíduos de (imazethapyr+imazapic) em um, dois e três anos de cultivo de arroz CL, e o fator B avaliou o efeito de dose sobre a atividade residual do herbicida. Os blocos foram constituídos por quatro unidades experimentais, que haviam recebido a mistura (imazethapyr+imazapic) nas doses de 0; 25+75; 37,5+112,5; e 50+150 g ha-1, acrescidos de Dash a 0,5% v/v. A análise conjunta dos dados, gerados nos três ambientes (A1, A2 e A3), acusou interação entre dose herbicida (imazethapyr+imazapic) e ambientes para as variáveis-resposta estatura de plantas e rendimento biológico. Para as variáveis peso de grãos e poder germinativo, as diferenças ocorreram somente entre as doses do herbicida. Os resultados demonstram que todas as variáveis-resposta avaliadas foram alteradas negativamente pela presença de resíduos da mistura (imazethapyr+imazapic) no solo, sendo maiores as injúrias com o incremento da dose. Foi observado que o cultivo de arroz irrigado no sistema CL deixa resíduos dos herbicidas (imazethapyr+imazapic) no solo, capazes de causar danos ao azevém cultivado em sucessão. Além disso, o sistema de sucessão envolvendo o arroz CL e azevém requer intervalos superiores a 180 dias entre a aplicação inicial do herbicida na primeira cultura e a semeadura do cultivo sucessor.

The aim of this study was to evaluate the residual activity of the prepackage mix of the herbicide Only (imazethapyr+imazapic) in a Clearfield (CL) rice production system during one, two or three rice seasons. The study was carried out in the field at Centro Agropecuário da Palma/Universidade Federal de Pelotas, Rio Grande do Sul, southern Brazil. Ryegrass (Lolium multiflorum) was planted after CL rice, cv. IRGA 422 CL. CL rice was considered as the main crop (summer) and ryegrass was planted following CL rice. The experimental design was a randomized complete block, with four replications. The treatments were arranged as a factorial: factor A, during the same season, compared herbicide residues during one, two or three years of CL rice and factor B, for herbicide rates. Herbicide (imazethapyr+imazapic) was applied at (0; 25+75; 37,5+112,5; 50+150) g ha-1 with surfactant Dash being added at 0.5% v/v. The results showed interaction between CL rice seasons and the herbicide rate for the variables plant height and biomass. All variables tested were affected by herbicide (imazethapyr+imazapic) residue and the effect was more severe at higher rates. Grain weight and germination percentage were only affected by the herbicide rates. The results showed also that the residue of herbicides (imazethapyr+imazapic) applied to CL rice may stay in the soil and affect ryegrass plants cultivated following CL rice. CL rice production system with herbicides (imazethapyr+imazapic) requires periods longer than 180 days for planting ryegrass as a successional crop.

Histiocytic necrotizing lymphadenitis (HNL), also known as Kikuchi 5 disease is a rare condition of unknown etiology. Patients present with cervical lymph node enlargement, fever and malaise. The diagnosis is made by excision biopsy. However, this entity must be distinguished from both reactive processes and malignant tumors such as lymphoma. The clinical course is self limited with spontaneous resolution within a few months. We report three patients with the disease. A 37 year-old woman with a 4 months history of a painless submaxillary mass of 2.5 cm diameter, attached to the deep tissues of the neck. The mass was excised and the biopsy report was HNL. After 26 months of follow up, the patient is asymptomatic. A 30 year-old woman with a history of 2 months of a painless lateral cervical mass and aspiration biopsy was reported as suspicious for lymphoma. An excision biopsy was performed, that was reported as HNL. In both patients, lymphoma was ruled out by immunohistochemistry. A 33 year-old woman with a 3 weeks history of an asymptomatic lateral cervical mass. Biopsy was reported as HNL. This condition must be included in the differential diagnosis of cervical asymptomatic masses. The clinician must be aware of it to avoid long-term, costly treatments

Background: Postoperative hypocalcemia is one of the most common complications of thyroid surgery. It is related to the type of disease (malignant or benign), the number of identified parathyroid glands during the surgical procedure, and the surgeon's experience. Total thyroidectomy is the procedure of choice in our hospital for benign and malignant thyroid disease, but it can increase the incidence of complications. Aim: To evaluate the incidence of postoperative hypocalcemia in patients subjected to a total thyroidectomy. Material and methods: Two studies were performed. A retrospective review of medical records of 448 patients subjected to total thyroidectomy, looking for serum calcium levels of less than 8 mg/dl and clinical signs of hypocalcemia. In a second study, 45 patients were followed with measurements of preoperative and postoperative serum calcium levels. Results: In the retrospective study, only 136 records had reliable information. Clinical signs of hypocalcemia were registered in 14% of patients and a low serum calcium level was detected in 50%. In the prospective study, 42% of patients had a postoperative low serum calcium level and seven patients (15%) had symptoms. Patients were handled with oral calcium and calcitriol in some cases. Ninety nine percent of patients had normal serum calcium levels two moths after surgery. Conclusions: In this series, the rate of postoperative hypocalcemia after total thyroidectomy is similar to internaitonal reports

Trace element concentrations in water from São Francisco River using Particle Induced X-ray Emission (PIXE) and Synchroton Total Reflection X-ray Fluorescence (STXRF) techniques are measured. The main objective of this work was to characterize and to monitor the trace elements in the water of São Francisco River, as well as to provide valuable information about the levels of metallic ions pollutants. Water samples were collected monthly at five locations along the course of the river from July 2003 to April 2004. As an internal standard, 11.6 ppm of Yttrium was added to 10 ml of the water sample. The PIXE and TXRF measurements were performed at the Ion Beams and Materials Laboratory (LAMFI) and the Brazilian National Synchrotron Light Laboratory (LNLS), using a proton beam and a polychromatic X-ray beam, respectively. Si(Li) detectors were used to collect the X-ray spectra. Due to the excellent detection limits of the PIXE and STXRF analysis, up to 15 elements were quantified. The highest total content of Cr, As, Cu and Zn detected in river water are above the limits recommended by the environmental legislation.

Concentrations of trace metallic element as well as macronutrients were measured in water and plants from pond water. The aquatic macrophyte Salvinia sp. was evaluated for its trace metals removal potential in river water under laboratory conditions. The experiment were performed using several healthy acclimatized plants Salvinia sp. The water and grown plants were collected from ponds. For the trace element removal´s test, 30-35 grams of fresh aquatic plants were grown in river water into a greenhouse for ten weeks. Control plants were also grown during the experiment. Every two weeks, both plants and water samples were collected. After the end of each experiment, the growth rate was calculated. Trace element concentrations in plants and pond water were obtained using TXRF techniques. Values for the elements (K, Ca, Ti, Fe, Cr, Mn, Cu, Zn and Sr) concentrations in plant dry weight have been obtained after deducting metal contents of control plants. For each trace element, the aquatic Salvinia sp. plant showed to possess different affinity for the incorporation of the metals in its biomass. Results suggest the use of aquatic macrophytes Salvinia sp. for metal abatement in dilute wastewaters.

This work presents an experimental study of purification of a biogas by removal of its hydrogen sulphide (H2S) content. The H2S was removed by means of chemical absorption in an iron-chelated solution catalyzed by Fe/EDTA, which converts H2S into elemental sulphur (S). Preparation of the catalyst solution and the results of biogas component absorption in the catalyst solution (0.2 mol/L) are presented. These results are compared with those for physical absorption into pure water under similar conditions. Experimental results demonstrate that, under the same experimental conditions, a higher percentage of H2S can be removed in the catalytic solution than in water. In a continuous counter current using adequate flow-rate phases contact at room temperature and low gas pressure, the results demonstrate that is possible to totally remove the H2S from the biogas with the prepared catalytic solution.

PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. Thirteen centers from Argentina, Brazil and Mexico participat ed during 1999-2000; they collected 1,806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1%) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3%) were penicillin-resistant and 79 (15.3%) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5%) and erythromycin (31.2%) resistance. Of 77 erythromycin-resistant S. pneumoniae tested for resistance genotype, 43 possessed mef(A), 33 possessed erm(B) and 1 possessed both erm(B) and mef(A) mechanism. All S. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. Among H. influenzae isolates, 88 (16.9%) produced b-lactamase, ranging from 11% (Brazil) to 24.5% (Mexico). Among M. catarrhalis isolates, 138 (98.6%) produced b-lactamase. Twenty-four (8.7%) of the S. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefA (n=18), ermTR (n=5) and ermB (n=1). All H. influenzae, M. catarrhalis and S. pyogenes were fully susceptible to telithromycin. Methicillin resistance was found in 26.5% of the S. aureus isolates (Argentina 15%; Mexico 20%; Brazil 31.3%). Telithromycin was effective against 97.7% of methicillin-susceptible isolates. PROTEKT confirms that antibacterial resistance is an emerging problem in Latin America. The previously reported high levels of pneumococcal resistance to the b-lactam and macrolides were exceeded. New agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy.