ABSTRACT Objective To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group. Methods A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded. Results The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups. Conclusion Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.

RESUMO Frente à crescente necessidade de recuperar o meio ambiente e seus recursos naturais, atualmente a reciclagem e reutilização dos materiais torna-se uma das soluções sustentáveis mais visadas. Neste cenário, o processamento de compósitos particulados de alumínio em matriz termoplástica de polietileno de baixa densidade (PEBD), provenientes da reciclagem de embalagens longa vida, apresenta-se de maneira atrativa para a obtenção de matéria prima para a construção civil, na fabricação de telhas de baixo peso, associado a baixo custo e elevada disponibilidade, dentre outras aplicações. Este trabalho tem por objetivo estudar as propriedades e o comportamento do compósito de polietileno de baixa densidade/alumínio reciclados. Com este objetivo, foi realizada a avaliação morfológica do compósito a partir de microscopia óptica (MO), microscopia eletrônica de varredura (MEV) e espectroscopia por energia dispersiva de raios X (EDS), bem como avaliados os comportamentos térmico e mecânico deste material após estes terem sido submetidos à climatização higrotérmica e por radiação ultravioleta (UV). Para a avaliação térmica foram empregadas técnicas de análise termogravimétrica (TGA) e calorimetria exploratória diferencial (DSC). As propriedades mecânicas foram avaliadas por análise dinâmico-mecânica (DMA) e ensaios de tração e impacto. A partir dos resultados obtidos por meio deste trabalho pode-se concluir que o intemperismo envolvendo umidade e radiação UV pode influenciar nos desempenhos térmico e mecânico do compósito de Alumínio/PEBD, porém, foi observado que esta influência não é suficiente para inviabilizar a utilização destes materiais na construção civil, garantindo este mercado para o compósito de PEBD/Al.

ABSTRACT Face the growing need to restore the environment and its natural resources, currently the recycling and reuse of materials becomes one of the most important sustainable solution. In this scenario, the processing of aluminum particulate composite with low density polyethylene thermoplastic matrix (LDPE) from recycling packages, presents an attractive way to obtain raw materials for the building industry, in the manufacturing of lightweight roof tiles, associated with low cost and high availability, among other applications. This work aims to study the properties and behavior of recycled low density polyethylene/aluminum composite. In order to do this, they were performed composite morphology assessment through optical microscopy (OM), scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS), as well as were evaluated the thermal and mechanical behavior of this material after being subjected to hygrothermal and ultraviolet conditioning (UV). For the thermal evaluation was performed thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The mechanical properties were evaluated by dynamic mechanical analysis (DMA) and tensile and impact tests. From the results obtained from this study it can be concluded that the moisture involving weathering and UV radiation can influence the thermal and mechanical performance of the composite aluminum / LDPE, but it was observed that this influence was not enough to prevent the use of these materials in construction, ensuring this market for LDPE / Al composite.

Tubos de aço são transportados diariamente em todo o mundo, por caminhão, trem ou navio. Conseqüentemente, danos de transporte, podem ocorrer com freqüência e regularidade. O tipo de dano particular selecionado para este estudo foi o de trinca por fadiga, o qual é considerado como um dos mais críticos. Neste trabalho foram estudados tubos de aço fabricados de acordo com os requisitos da norma API 5L [1]. Foram efetuadas caracterizações químicas, mecânicas e metalográficas de um tubo com diâmetro 609,6 mm e espessura 15,87 mm grau X-65. A simulação do transporte por navio de tubos de aço foi feita submetendo-se seções de tubo com comprimento igual a 0,1 metro, a ciclos de fadiga por meio de máquina servo-hidráulica. Foi possível concluir que em tubos soldados, a região adjacente ao cordão de solda é a mais crítica, e que quando o posicionamento do tubo na carga é efetuado de maneira que a solda fique apoiada sobre alguma superfície rígida, a ocorrência de trinca por fadiga torna-se possível principalmente se os procedimentos de manuseio, carregamento e transporte não forem executados da maneira como recomendada pelos fabricantes de tubos e pela norma API [2].

Steel pipes are daily transported all over the world by truck, train or ship. Consequently, shipping damages may occur frequent and regularly. The particular damage selected for this study was fatigue cracking, that is considered as the more critical one. In this job were studied steel pipes manufactured according to the requirements of the specification API 5L [1]. Chemical, mechanical and micrographic characterizations were made in a pipe size Ø 609.6 mm x 15.87 mm grade X-65. For the simulation of a ship transportation of steel pipes, pipe lengths sections of 0.1 meter were submitted to fatigue cycles from a servo-hydraulic machine. It was possible to conclude that in welded pipes, the weld region adjacent to the weld toe is the more critical and when the pipe positioning at the vessel result in to be the weld in contact with rigid surface, the occurrence of fatigue cracking is possible mainly if the handling, loading and transportation procedures were not executed as recommended by the pipe manufacturers and by the API specification.

Titanium alloys have several advantages over ferrous and non-ferrous metallic materials, such as high strengthto-weight ratio and excellent corrosion resistance. A blended elemental titanium powder metallurgy process has been developed to offer low cost commercial products. The process employs hydride-dehydride (HDH) powders as raw material. In this work, results of the Ti-35Nb alloy sintering are presented. This alloy due to its lower modulus of elasticity and high biocompatibility is a promising candidate for aerospace and medical use. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by isochronal sintering between 900 up to 1600 °C, in vacuum. Sintering behavior was studied by means of microscopy and density. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. Samples sintered at high temperatures display a fine plate-like alpha structure and intergranular beta. A few remaining pores are still found and density above 90% for specimens sintered in temperatures over 1500 °C is reached.