Abstract: A procedure for the study of the flow-induced vibration (FIV) phenomenon of pipes conveying turbulent Newtonian fluid flow is proposed. A numerical model that considers the fluid-structure interaction through the bidirectional coupling between these physical domains is used. The Finite Volume and Finite Element methods, respectively, are used to solve the fluid-dynamic and structural domains. The model considers: (i) periodicity condition for quickly obtaining a fully developed turbulent flow, (ii) WMLES S Omega model for turbulence, (iii) pipe with linear elastic material, and (iv) large displacements theory. The model is implemented in ANSYS 2019 R1 software. Three water flow conditions in a clamped-clamped horizontal PVC pipe with 20.4 mm internal diameter are simulated. The results show the same velocity effects on the amplitude and frequency vibration reported by experimental and analytical studies, validating the proposed procedure.

Resumen: Se propone un procedimiento para estudiar el fenómeno de vibración inducida por flujo (FIV) en tuberías que transportan fluido newtoniano en régimen turbulento. Se usa un modelo numérico que considera la interacción fluido-estructura a través del acoplamiento bidireccional entre estos dominios físicos. Se emplean los métodos de Volúmenes Finitos y Elementos Finitos para resolver los dominios fluidodinámico y estructural, respectivamente. Se considera: (i) condición de periodicidad para obtener rápidamente un flujo turbulento totalmente desarrollado, (ii) modelo WMLES S-Omega para la turbulencia, (iii) tubería de material elástico lineal, y (iv) teoría de grandes desplazamientos. El modelo se implementa en el software ANSYS 2019 R1. Se simulan tres condiciones de flujo de agua en una tubería horizontal biempotrada de PVC de 20.4 mm de diámetro interno. Los resultados muestran los mismos efectos de la velocidad sobre la amplitud y frecuencia de vibración que los reportados en estudios experimentales y analíticos, validando el procedimiento propuesto.

Resumo Animais cativos exibem a estereotipia pacing em resposta a múltiplos fatores, os quais incluem a incapacidade de escapar da exposição ao público. As técnicas de enriquecimento ambiental podem minimizar a expressão do pacing. Usando uma abordagem individual, nós investigamos se a extensão de tempo que dois machos e uma fêmea de onça-pintada (Panthera onca) dispendem com pacing variou em função do número de visitantes e testamos a eficácia da canela e da pimenta-do-reino na redução do pacing. A extensão de tempo em pacing aumentou significativamente com o número de visitantes para todos os indivíduos. Apesar da diferença entre os machos com relação à idade e às condições no cativeiro, ambos devotaram ao pacing menos tempo após a administração das duas especiarias, o que indica a adequabilidade dessas como técnicas de enriquecimento. Para a fêmea, o tempo médio dispendido com pacing não variou entre os tratamentos. Nossos resultados respaldam a validade da realização de abordagens individuais, uma vez que essas podem revelar o grau de eficácia dos estímulos olfativos na minimização de estereotipias independentemente de características particulares.

Abstract Captive animals exhibit stereotypic pacing in response to multiple causes, including the inability to escape from human contact. Environmental enrichment techniques can minimize pacing expression. By using an individual-based approach, we addressed whether the amount of time two males and a female jaguar (Panthera onca) devote to pacing varied with the number of visitors and tested the effectiveness of cinnamon and black pepper in reducing pacing. The amount of time that all jaguars engaged in pacing increased significantly with the number of visitors. Despite the difference between the males regarding age and housing conditions, both devoted significantly less time to pacing following the addition of both spices, which indicates their suitability as enrichment techniques. Mean time devoted to pacing among the treatments did not differ for the female. Our findings pointed out to the validity of individual-based approaches, as they can reveal how suitable olfactory stimuli are to minimizing stereotypies irrespective of particular traits.

Tuberous breasts, denominated like this by Rees and Aston, and also called areolar complex hernia by Bass, Snoopy deformity by Gruber, tubular breasts by Williams, inferior pole hypoplasia by Brink, tight base breasts by Puckett, are a malformation of breast with inferior quadrants alteration that produce an areolar herniation and protrusion (in fifty per cent of the cases), and elevation of the infamammary fold; they are rarely hypertrophic and with asymmetries in two thirds of the patients. Authors present the surgical strategy to solve this pathology just using high cohesive silicone gel anatomical implants without needing of glandular flap tailoring. By this way, surgical morbidity is diminished offering stable results and high patient satisfaction.

Las mamas tuberosas, denominadas así por Rees y Aston, y también llamadas hernias del complejo areolar (Bass), Snoopy deformity (Gruber), mamas tubulares (Williams), hipoplasia del polo inferior (Brink) o mamas de base estrecha (Puckett), son una malformacion en el desarrollo del volumen mamario en los cuadrantes inferiores con hernia areolar secundaria (placa areolar y músculo mamilar débiles), areola ancha y protruida (en la mitad de los casos), ascenso del surco submamario, mamas hipotróficas y raramente hipertróficas, con asimetrías en las dos terceras partes de las pacientes. Presentamos la estrategia quirúrgica adecuada para resolver esta patología utilizando solo implantes anatómicos de gel cohesivo sin necesidad de tallar colgajos glandulares. De esta manera, disminuimos la morbilidad quirúrgica, ofreciendo resultados estables y con alta satisfaccion por parte de las pacientes.

An analysis was made of the problem of the high percentage of course failure in the science area within the agricultural engineering career of the University of Concepción in Chile. For this, two questionnaires were selected and contrasted after application to four groups of students. The results suggested that besides not having the basic concepts that a given course requires, the students did not have study habits and positive attitude to studying. All this prevent students to assimilate the subjects and pass the courses. It is concluded that the greatest problems confronted by the students are lack of reading and note-taking skills, inadequate programming of their time, failure to concentrate, and lack of adequate study areas.

En este trabajo se analiza el problema del alto porcentaje de alumnos reprobados en los cursos del área de ciencias en la carrera de Ingeniería Civil Agrícola de la Universidad de Concepción en Chile. Para este estudio se seleccionaron y contrastaron dos encuestas que se aplicaron a cuatro grupos de estudiantes. Los resultados obtenidos indican que aparte de no tener los conocimientos básicos que requiere el curso, los estudiantes tampoco poseen hábitos y actitudes propias para el estudio. Todo esto no permite a los alumnos asimilar las materias y aprobar estos cursos. Se concluye que los mayores problemas que enfrentan los estudiantes, son la falta de técnicas adecuadas para leer y tomar apuntes, la inadecuada distribución de su tiempo, la falta de concentración y la falta de sitios adecuados para estudiar.

The present study was carried out in order to compare the effects of administration of organic (methylmercury, MeHg) and inorganic (mercury chloride, HgCl 2 ) forms of mercury on in vivo dopamine (DA) release from rat striatum. Experiments were performed in conscious and freely moving female adult Sprague-Dawley (230-280 g) rats using brain microdialysis coupled to HPLC with electrochemical detection. Perfusion of different concentrations of MeHg or HgCl 2 (2 µL/min for 1 h, N = 5-7/group) into the striatum produced significant increases in the levels of DA. Infusion of 40 µM, 400 µM, or 4 mM MeHg increased DA levels to 907 ± 31, 2324 ± 156, and 9032 ± 70% of basal levels, respectively. The same concentrations of HgCl 2 increased DA levels to 1240 ± 66, 2500 ± 424, and 2658 ± 337% of basal levels, respectively. These increases were associated with significant decreases in levels of dihydroxyphenylacetic acid and homovallinic acid. Intrastriatal administration of MeHg induced a sharp concentration-dependent increase in DA levels with a peak 30 min after injection, whereas HgCl 2 induced a gradual, lower (for 4 mM) and delayed increase in DA levels (75 min after the beginning of perfusion). Comparing the neurochemical profile of the two mercury derivatives to induce increases in DA levels, we observed that the time-course of these increases induced by both mercurials was different and the effect produced by HgCl 2 was not concentration-dependent (the effect was the same for the concentrations of 400 µM and 4 mM HgCl 2 ). These results indicate that HgCl 2 produces increases in extracellular DA levels by a mechanism differing from that of MeHg.

Aim: To know the number of patients that are admitted in the hospital with TED or those who have developed it during their stay, analyzing how to manage this disease and make a basis for a prospective study of this disease. Methods: It is a descriptive and retrospective study of TED diagnosed patients during their stay at the Hospital Clínico San Carlos of Madrid for a 6 month period. Data related with epidemiologic records, diagnosis, treatment and complications of patients with Deep-Vein Thrombosis (DVT), Pulmonary Thromboembolism (PTE) or both (DVT+PTE) are collected. Results: From October 1st of 2003 to March 31st of 2004, 239 patients were diagnosed with TED (64 DVT, 125 PTE y 51 DVT + PTE) when they were discharged from our hospital, with an average age of 73.2 years (standar desviation 13.64). We classify as risky factors with significative statistical diferences chemotherapy, acute myocardium infarction and obesity. It has not been found any relation between the treatment used and the development of hemorrage. Patients with previous episodies of TED had more frequent hemorragies than those without such records. Hypokinesia in the right ventricle shown on the echocardiogram supposed a gloomy prognosis of the death for TED as well as the development of DVT + PTE. Conlusion: In more than a 50% of patients, TED was PTE and more than a 60% were women. It is important to obtain information about these patients because 2/3 of them are admitted to internal medicine. Chemotherapy, AIM and obesity were factors significatively associated to DVT, PTE and DVT + PTE. Hypokinesia in the right ventricle shown on the echocardiogram supposed a gloomy prognosis for TED as well as the development of DVT + PTE.

Objetivo: Conocer el número de pacientes que ingresan o que desarrollan durante su ingreso en un hospital ETEV, analizar el manejo de esta enfermedad y sentar las bases para un estudio prospectivo de dicha enfermedad. Métodos: Se trata de un estudio descriptivo retrospectivo de pacientes diagnosticados de ETEV durante su ingreso en el Hospital Clínico San Carlos de Madrid en un período de 6 meses. Se recogen los datos relacionados con antecedentes epidemiológicos, diagnóstico, tratamiento y complicaciones de los pacientes con trombosis venosa profunda (TVP), tromboembolismo pulmonar (TEP) o ambas (TVP + TEP). Resultados: Del 1 de octubre de 2003 al 31 de marzo de 2004, 239 pacientes fueron diagnosticados de ETEV (64 TVP, 125 TEP y 51 TVP + TEP) al alta en nuestro hospital con una edad media de 73,2 años (desviación estándar 13,64). Como factores de riesgo con diferencias estadísticamente significativas detectamos la quimioterapia, el infarto agudo de miocardio y la obesidad. No se ha observado relación entre el tipo de tratamiento utilizado y la aparición de hemorragia. Los pacientes con episodios previos de ETEV presentaron hemorragias más frecuentemente que aquellos sin dichos antecedentes. La hipocinesia de ventrículo derecho en el ecocardiograma fue un factor de mal pronóstico para la muerte por ETEV así como la aparición de TVP + TEP. Conclusión: En más del 50% de los pacientes la ETEV era TEP y más del 60% eran mujeres. Es importante disponer de información sobre estos pacientes, ya que 2/3 ingresan en medicina interna. La quimioterapia, el IAM y la obesidad fueron factores que se asociaron a TVP, TEP y TVP + TEP de forma significativa, respectivamente. La hipocinesia de ventrículo derecho en el ecocardiograma fue un factor de mal pronóstico para la muerte por ETEV así como la coincidencia de TVP + TEP.

We describe the management and clinical outcome of three pregnancies whose fetal lung maturity test in amniotic fluid showed an immature lecithin/sphingomyelin (L/S) ratio (< 2) but presence of phosphatidylglycerol. Here we reviewed the ability of both tests to predict fetal lung maturity. It has been reported that in the presence of phosphatidylglycerol when L/S ratio is greater than 2 the probability of hyaline membrane disease in the neonate is nearly cero. However, in those cases with L/S index between 1.5 and 1.9 the probability of the disease reaches to 3.4%. In these patients we recommend, if allowed by the maternal and fetal condition, to delay pregnancy interruption for one week.

Reportamos el manejo y evolución de tres embarazos cuyo estudio de índices de madurez pulmonar en el líquido amniótico mostró lecitina/esfingomielina (L/E) inmaduro (< 2) con fosfatidilglicerol presente. Agregamos una revisión respecto de la capacidad de ambos test de predecir madurez pulmonar. Se ha descrito que cuando el fosfatidilglicerol está presente, aquellas pacientes con un índice de L/E > 2 tiene una probabilidad cercana a cero de presentar enfermedad de membrana hialina neonatal. Por el contrario aquellos casos en los que el índice L/E presenta entre 1,5 y 1,9 la probabilidad de desarrollar la enfermedad es de un 3,4%. Para este último grupo recomendamos que, si la condición fetal y materna lo permiten, la interrupción del embarazo sea diferida en una semana

In order to improve the results given by Autoregressive Moving-Average (ARMA) modeling for the monthly accumulated rainfall series taken at 19 observatories of the Iberian Peninsula, a Discrete Linear Transfer Function Noise (DLTFN) model was applied taking the local pressure series (LP), North Atlantic sea level pressure series (SLP)and North Atlantic sea surface temperature (SST) as input variables, and the rainfall series as the output series. In all cases, the performance of the DLTFN models, measured by the explained variance of the rainfall series, is better than the performance given by the ARMA modeling. The best performance is given by the models which take the local pressure as the input variable, followed by the sea level pressure models and the sea surface temperature models. Geographically speaking, the models fitted to those observatories located in the west of the Iberian Peninsula work better than those on the north and east of the Peninsula. Also, it was found that there is a region located between 0°N and 20°N, which shows the highest cross-correlation between SST and the peninsula rainfalls. This region moves to the west and northwest off the Peninsula when the SLP series are used.

Con el objeto de mejorar los resultados proporcionados por los modelos Autorregresivo - Media Móvil (ARMA) ajustados a las precipitaciones mensuales acumuladas registradas en 19 observatorios de la Península Ibérica se han usado modelos de función de transferencia (DLTFN) en los que se han empleado como variable independiente la presión local (LP), la presión a nivel del mar (SLP) o la temperatura de agua del mar (SST) en el Atlántico Norte. En todos los casos analizados, los resultados obtenidos con los modelos DLTFN, medidos mediante la varianza explicada por el modelo, han sido mejores que los resultados proporcionados por los modelos ARMA. Los mejores resultados han sido dados por aquellos modelos que usan la presión local como variable de entrada, seguidos por los modelos que emplean la presión a nivel del mar, siendo los modelos que emplean la temperatura del agua del mar los que peores resultados proporcionan. Con referencia a la situación geográfica, los modelos ajustados a los observatorios localizados al oeste de la Península dan mejores resultados que los ajustados a los observatorios situados al norte y este de la misma. Asimismo se ha encontrado que existe una región en el Atlántico Norte situada entre los paralelos 0º y 20°N donde la temperatura del agua parece tener alguna influencia sobre las precipitaciones peninsulares. Esta región se traslada hacia el norte cuando se emplean presiones a nivel del mar, a la vez que se intensifica su influencia.