Técnica para redução de tempo no cálculo de autovalores e autovetores aplicados a problemas de fonte fixa em transporte de nêutrons

In this work, a mathematical technique to accelerate the eigenvalue calculations, originally proposed for the Analytical Discrete Ordinates method (ADO), is applied to the coarse-mesh method Modified Spectral Deterministic (MSD), used in neutron shielding problems (fixed-source) in one-dimensional geometry. This technique consists in an arrangement of the neutron transport equation which leads to a reduced eigenvalue calculation on the intranodal analytical solution, where only the positive half of the eigenvalues and its respective eigenvectors are calculated, hence reducing the methods execution time. Precision and performance tests were performed in 2 model-problems, reducing around 80% of the execution time. All the codes were developed using the programming language C++.Neste trabalho, uma técnica matemática para acelerar os cálculos de autovalores, originalmente proposto para o método Analytical Discrete Ordinates (ADO), é aplicado para o método de malha grossa Modified Spectral Deterministic (MSD), usado em problemas de blindagem de nêutrons (fonte-fixa) em geometria unidimensional. Esta técnica consiste no arranjo da equação de transporte de nêutrons que leva a cálculos reduzidos de autovalores, onde são calculados apenas os autovalores positivos e seus respectivos autovetores, consequentemente reduzindo o tempo de execução do método. Testes de precisão e performance são realizados em 2 problemas-modelo, onde foram reduzidos cerca de 80% do tempo de execução. Todos os códigos foram desenvolvidos usando a linguagem de programação C++

Diagnóstico inicial da presença de metais pesados em sedimento e em organismos bentônicos da ilha de Itacolomi, PR

O presente trabalho teve como objetivo fazer um diagnóstico inicial da presença de cádmio (Cd), aresênio (As), mercúrio (Hg) e chumbo (Pb) na ilha de Itacolomi no litoral do Paraná. A análise foi feita a partir da coleta das espécies Anisotremus surinamensis (Bloch, 1791), Holocentrus adscensionis (Osbeck, 1765), Echinometra lucunter (Linnaeus, 1758) e a camada superficial de sedimento marinho em quatro pontos ao redor da ilha de Itacolomi. As amostras foram abertas utilizando a digestão ácida e analisadas em um espectrômetro de absorção atômica. As concentrações médias obtidas no presente estudo foram de 0,435 µg.g-1 para o Cd, 0,296 µg.g-1 para o Hg; o As não foi detectado e o Pb ficou abaixo do limite de quantificação para o tecido muscular da espécie H. adscensionis. Para a espécie A. surinamensis, as concentrações médias foram de 0,785 µg.g-1 para o As, enquanto para os metais Cd, Hg e Pb, as médias ficaram abaixo do limite de quantificação, também para o tecido muscular. No ouriço do mar E. lucunter o tecido gonadal apresentou as médias de 6,118 µg.g-1 para o As, 0,205 µg.g-1 para o Hg, enquanto o Cd e o Pb apresentaram médias abaixo do limite de quantificação. Na análise da presença de metais pesados no sedimento superficial, ficou evidenciado um valor médio de 0,5047 µg.g-1 para o Cd, valor médio de 3,2752 µg.g-1 para o As, 0,2235 µg.g-1 para o Hg e 0,4038 µg.g-1 para o Cu. Os resultados apresentados neste trabalho, demonstraram a presença de metais pesados abaixo dos limites estabelecidos para consumo humano (Cd e As= 1 µg.g-1; Hg = 0,5 µg.g-1; Pb = 2 µg.g-1)

Valor de predição da ultrassonografia cerebral em recém-nascidos pré-termo para alteração de desenvolvimento neuropsicomotor aos 12 meses de idade corrigida

OBJETIVO: verificar o valor preditivo da ultrassonografia transfontanelar em recém-nascidos prematuros na determinação das alterações do desenvolvimento neuropsicomotor. MÉTODO: coorte prospectivo. Foram estudados 99 recém-nascidos prematuros com peso de nascimento menor ou igual a 1800 gramas e idade gestacional abaixo de 37 semanas que fizeram ultrassom transfontanelar no período neonatal durante internação em UTI. Para avaliação do desenvolvimento neuropsicomotor utilizou-se o Teste de Denver II. Na análise bivariada utilizou-se o teste do qui-quadrado e na análise multivariada, regressão logística onde foram detectadas associações entre características sócio-econômicas e a variável resposta. Finalmente foi realizada análise para avaliação de valores preditivos positivos e negativos. RESULTADOS: população composta de crianças com 12 meses de idade corrigida, com média de peso de nascimento de 1320 gramas e idade gestacional média de 31 semanas e 3 dias. Alterações ultra-sonográficas estiveram presentes em 49,4% das crianças. Dos testes realizados, 34,3% tiveram resultados desfavoráveis. Dos fatores de risco para alteração de desenvolvimento, alterações ultra-sonográficas cerebrais e renda familiar mostram-se estatisticamente significantes. O valor preditivo positivo dos exames ultra-sonográficos transfontanelares para alterações de desenvolvimento neuropsicomotor, foi de 51,02 % e o negativo, 82%. Acrescentando-se a variável renda familiar às alterações ultra-sonográficas transfontanelares, o valor preditivo positivo aumentou para 90% e o negativo reduziu-se para 71,91%. CONCLUSÃO: acredita-se que o acréscimo à análise da variável renda familiar é boa alternativa para aumentar a capacidade de predizer o desenvolvimento de prematuros com alterações ultra-sonográficas transfontanelares.OBJECTIVE: verify the predictive value of transfontanellar ultrasonic exams in premature babies on determination of altered neural psychomotor development. METHOD: prospective cohort.: Ninety-nine premature infants with birth weights of 1800 g or less and gestational ages of less than 37 weeks who had had neonatal transfontanellar ultrasound scans when they were in intensive care were studied. The Denver II test was used to assess neurodevelopment. The chi-square test and logistic regression were used in the bivariate and multivariate analyses, respectively, and revealed associations between the socioeconomic characteristics and dependent variable. Lastly, an analysis was carried out to determine positive and negative predictive values. RESULTS: the population consisted of children with a corrected age of 12 months, average birth weight of 1320 g and average gestational age of 31 weeks and 3 days. Ultrasound abnormalities were detected in 49.4% of the children. Of the tests carried out, 34.3% yielded unfavorable results. Among the risk factors for delayed development, abnormal ultrasound results and family income were statistically significant. The positive and negative predictive values of the transfontanellar ultrasound scans for altered neurodevelopment were 51,02 % and 82 %, respectively. When the variable"family income" was used together with"altered ultrasound results", the positive predictive value increased to 90% and the negative predictive value fell to 71.91%. CONCLUSION: inclusion of"family income" is an effective way of increasing the predictive value of abnormal transfontanellar ultrasound results for altered neurodevelopment in premature infants

Malignant Alveolar Neoplasm in a 10-Month-Old French Bulldog

Background: Malignant tumors are the main cause of death or euthanasia in animals. The oral cavity ranking fourth in number of occurrences. Epidemiological studies with dogs suggest that canine cancer kills 40-50% of individuals aged over 10 years. In view of the interest of academics and professionals in the healthcare of dogs and cats, this paper reports the case of a 10-month-old bitch, which, despite being a young animal, was affected alveolar rhabdomyosarcoma of abrupt evolution. Case: A 10-month-old French Bulldog bitch, weighing 10 kg, was referred to a veterinary hospital in the city of Rio de Janeiro for care. It had a history of mouth bleeding, after chewing a solid mineral material, edema in the region of the right maxilla, and protusion of the gland of the third eyelid. As the clinical examination also revealed a fracture of the maxillary canine, anti-inflammatory and antibiotics were prescribed, to be administered by the owner once a day for 7 days. During the next clinical examination, carried out one week later, an edema was found in the right region of the mouth, which proved difficult to examine. As the patient had already eaten, an appointment was made for the following day for an intervention int he operating room, where the animal could be anesthetized for better observation of the effected region. Blood was collected for hemogram, urea, creatinine, alkaline phosphatase, ALT, and GGT, and an 8 h food fasting and a 4 h water fasting were recommended. On that date, once the dog had been taken to the operating room, was administered the pre anesthesia, in addition to anesthetic induction and manutention. Upon examining the oral cavity, several loose molars were found on the right side, in addition to a tumoral aspect of the gum; thus, it was decided to collect a small sample of the tumoral mass for histopathology. The surgical specimen was placed in a formalin solution and sent to the laboratory for histopathological processing and diagnosis. One week later, the tumor mass was larger and the edema in the right region of the mouth was much larger than on the day of the procedure. Thus, a computerized tomography was requested to further investigate the alterations that had occurred in such a short time. Due to the results of the histopathology and the CT, an immunohistochemical test was suggested which determined the cell profile and morphology and confirmed the diagnosis of alveolar rhabdomyosarcoma according to clinical suspicion. The animal remained in the veterinary hospital for a further 48 h, during which the clinical condition worsened, with the animal suffering heavy bleeding. As the patient was no longer capable of oral intake of food or water, the decision was made with the consent of the owners to induce a painless death to alleviate the suffering of the animal. However, the owners did not authorize a necropsy. Discussion: Veterinary physicians should be conscious of the treatment of serious illnesses that will not result in a benefit for the patient. They should know when to stop the treatment to not cause further pain and suffering to the animals and their owners. Many of the interventions which aim to treat severe malignant neoplasia will not promote an improvement in quality of life or significantly extend the patient’s survival, and do not justify the suffering they entail. A painless death remains the best alternative in such cases. Keywords: cancer, malignant neoplasm, alveolar rhabdomyosarcoma, oral cavity

Development of a biaxial tensile device in the plane for monotonic mechanical tests and cruciform specimens / Desenvolvimento de um dispositivo de tração biaxial no plano para ensaios mecânicos monotônicos e de corpos de prova cruciformes

This work deals with the development of a coupling device for performing biaxial tensile tests with cruciform specimens. For the project, a methodology consisting of six phases was used, that is, informational design, conceptual design, preliminary design, detailed design, manufacturing and testing. Thus, the design and sizing of two coupling devices was carried out, and the model chosen for manufacturing was based on that proposed by Rohr, Harwick, and Nahme. In addition, the design, sizing and fabrication of cruciform specimens in MDF and PS, with geometry similar to that of ISO 16842:2014, was also carried out for the device validation tests. The tests were divided into 1) device stiffness test and 2) specimen deformation test for equibiaxial testing. The proposed test setup was designed to test cruciform specimens with dimensions up to 350 x 350 x 4 mm and support a maximum vertical load of up to 30 kN

Nutritional supplementation and growth after hospital discharge in very low birthweight newborns: Randomized controlled trial / Suplementação nutricional e crescimento de recém-nascidos de muito baixo peso após alta hospitalar: Ensaio clínico randomizado

Background Evidence is insufficient to show whether fortification has any effect on growth in preterm infants after discharge. Objective to verify whether VLBW preterm infants who are supplemented with multicomponent present greater anthropometric measurements than those not supplemented. Study Design Parallel randomized controlled trial. A computer-generated random number table was used to allocate the participants. Participants Preterm infants discharged from the NICU of a University Hospital from northeast, Brazil, weighing less than 1,500 g exclusively breastfed at discharge and followed up until they reached 6 months corrected gestational age.  Intervention intervention group received Nestlé® PreNan® formula, fractionated in 2 g of powder, mixed with the mother's milk twice a day. Control group was exclusively breastfed. Follow-up was conducted until the infants reached 6 months corrected gestational age (CGA). Outcomes Growth of the anthropometrics parameters weight, head circumference (HC) and lenth with 6 months of corrected age.  Mixed effects model for longitudinal data was used. Interaction according to sex was detected and ajusted. Results Weight gain was significantly higher in the intervention group. This effect was verified only for males (p = 0.001). No statistically significant association was observed between the intervention and the head circumference or length (p = 0.211; 0.597). The weaning rate at the end of follow-up was similar in both groups. Conclusions Breastmilk supplementation may improve the weight gain of very low birthweight preterm infants up to six months corrected gestational age. This effect differed by sex and was considered significant only for males