Multi-fluid flows with the particle finite element method

Particle methods are those in which the problem is represented by a discrete number of particles. Each particle moves accordingly with its own mass and the external/internal forces applied on it. In this paper the Particle Finite Element Method based on finite element shape functions is used to solve the continuous fluid mechanics equations in the case of heterogeneous density. To evaluate the external applied forces to each particle, the incompressible Navier–Stokes equations are solved at each time step using a Lagrangian formulation. All the information in the fluid is transmitted via the particles. All kinds of density heterogeneous fluids and multiphase flows with internal interfaces including or not free-surfaces, breaking waves and fluid separations may be easily solved with this methodology.&nbsp

The Particle Finite Element Method for multi-fluid flows

This paper presents the Particle Finite Element Method (PFEM) and its application to multi-fluid flows. Key features of the method are the use of a Lagrangian description to model the motion of the fluid particles (nodes) and that all the information is associated to the particles. A mesh connects the nodes defining the discretized domain where the governing equations, expressed in an integral form, are solved as in the standard FEM.We have extended the method to problems involving several different fluids with the aim of exploiting the fact that Lagrangian methods are specially well suited for tracking any kind of interfaces

Numerical simulations of negatively buoyant jets in an immiscible fluid using the Particle Finite Element Method

Negatively buoyant jets consist in a dense fluid injected vertically upward into a lighter ambient fluid. The numerical simulation of this kind of buoyancy‐driven flows is challenging as it involves multiple fluids with different physical properties. In the case of immiscible fluids, it requires, in addition, to track the motion of the interface between fluids and accurately represent the discontinuities of the flow variables. In this paper, we investigate numerically the injection of a negatively buoyant jet into a homogenous immiscible ambient fluid using the Particle Finite Element Method and compare the two‐dimensional numerical results with experiments on the injection of a jet of dyed water through a nozzle in the base of a cylindrical tank containing rapeseed oil. In both simulations and experiments, the fountain inlet flow velocity and nozzle diameter have been varied to cover a wide range of Froude Fr and Reynolds Re numbers ( 0.1 < Fr < 30, 8 < Re < 1350), reproducing both weak and strong laminar fountains. The flow behaviors observed for the different numerical simulations fit in the regime map based on the Re and Fr values of the experiments, and the maximum fountain height is in good agreement with the experimental observations, suggesting that particle finite element method is a useful tool for the study of immiscible two‐fluid systems

Efectos adversos de la vacunación contra el virus del papiloma humano

ResumenObjetivoDescribir las reacciones adversas más frecuentes producidas por la vacunación contra el virus del papiloma humano (VPH).DiseñoEstudio descriptivo transversal mediante encuesta telefónica.EmplazamientoSistema Sanitario Público de Andalucía.ParticipantesMujeres vacunadas frente al VPH en Andalucía, seleccionadas por muestreo aleatorio simple con representatividad provincial.MedicionesSe realizaron 3.135 llamadas telefónicas por el servicio público “Salud Responde” dependiente de teleoperadores con supervisión de personal sanitario.Resultados principalesDe las 2.880 llamadas que cumplían criterio de inclusión, se consiguió encuestar a 1.207 personas (41,9% de respuesta). De las 2.124 encuestas realizadas tuvieron algún tipo de reacción adversa (fiebre, inflamación, dolor o enrojecimiento) en 467 dosis (22%): el 6,6% fue fiebre, el 49,5% inflamación, el 72,4% dolor, y el 6% enrojecimiento.ConclusionesSe puede decir que es una vacuna segura, lo que concuerda con lo recogido en su ficha técnica y en la literatura.AbstractObjectiveTo describe the most frequent adverse reactions produced by the human papillomavirus (HPV) vaccine.DesignCross-sectional descriptive study using a telephone survey.SettingA province in the Andalusian Public Health System.ParticipantsFemales vaccinated against HPV in Andalusia, selected by simple random sampling representative of the province.Main measurementsA total of 3,135 telephone calls were made by the public service “Health Answers” using telephone operators supervised by health personnel.ResultsOf the 2,880 calls that fulfilled the inclusion criteria, 1,207 people (41.9% response) took part in the survey. Of the 2,124 surveys made there was some type of adverse reaction (fever, inflammation, pain or rash) in 467 doses (22%): 6.6% was fever, 49.5% inflammation, 72.4% pain, and 6% a rash.ConclusionsIt can be said that HPV vaccine is safe, which is in agreement with that published in the summary of the product characteristics and in the literature

Fossil Groups Origins III. Characterization of the sample and observational properties of fossil systems

(Abridged) Fossil systems are group- or cluster-sized objects whose luminosity is dominated by a very massive central galaxy. In the current cold dark matter scenario, these objects formed hierarchically at an early epoch of the Universe and then slowly evolved until present day. That is the reason why they are called {\it fossils}. We started an extensive observational program to characterize a sample of 34 fossil group candidates spanning a broad range of physical properties. Deep $r-$band images were taken for each candidate and optical spectroscopic observations were obtained for $\sim$ 1200 galaxies. This new dataset was completed with SDSS DR7 archival data to obtain robust cluster membership and global properties of each fossil group candidate. For each system, we recomputed the magnitude gaps between the two brightest galaxies ($\Delta m_{12}$) and the first and fourth ranked galaxies ($\Delta m_{14}$) within 0.5 $R_{{\rm 200}}$. We consider fossil systems those with $\Delta m_{12} \ge 2$ mag or $\Delta m_{14} \ge 2.5$ mag within the errors. We find that 15 candidates turned out to be fossil systems. Their observational properties agree with those of non-fossil systems. Both follow the same correlations, but fossils are always extreme cases. In particular, they host the brightest central galaxies and the fraction of total galaxy light enclosed in the central galaxy is larger in fossil than in non-fossil systems. Finally, we confirm the existence of genuine fossil clusters. Combining our results with others in the literature, we favor the merging scenario in which fossil systems formed due to mergers of $L^\ast$ galaxies. The large magnitude gap is a consequence of the extreme merger ratio within fossil systems and therefore it is an evolutionary effect. Moreover, we suggest that at least one candidate in our sample could represent a transitional fossil stage.Comment: 14 pages, 11 figures, accepted for publication in A&

El yacimiento arqueológico de El Saucedo (Talavera La Nueva, Toledo): balance y perspectivas

En este artículo presentamos una síntesis de los trabajos de investigación, conservación y difusión reali-zados en el yacimiento de b'l Saucedo hasta el presente, así como un esbozo de los planes de actuación para el futuro

Acinic cell carcinoma of the parotid gland with four morphological features

Acinic cell carcinoma arising in salivary glands is a rare tumor, accounting for 2% to 5% of the primary neoplasms of the parotid gland. When these tumors are well-differentiated, the neoplasia has innocuous aspect, due to the similarity to normal parotid tissue. This makes the diagnosis difficult. Initially the malignancy of this tumor was uncertain; however, recent studies have declared it as malignant. The female / male ratio is 3:2. The nodule usually presents as solitary and well defined shape. Several authors have used different terms to describe histomorphological patterns of these tumors. Four descriptive categories (solid, microcystic, papillary-cystic and follicular) are useful for pathologists. Here we report a case of a 49 yr old man with a left parotid nodule of 5 cm. Parotidectomy was performed at the Hospital Universitario Miguel Servet, in Zaragoza (Spain). The microscopy showed a tumor with acinic semblance, having the four morphologic patterns previously described. The morphological and immunohistochemical study was consistent with the diagnosis of acinic cell carcinoma

¿Cuánta desigualdad en exposición a alta polución por PM10 es demasiada para considerarla ambientalmente injusta? Una evaluación para grupos vulnerables en dos grandes ciudades españolas

Inequality in the environmental conditions or burden (negative externalities, hazards, discomfort, etc.) between places and people is an issue of growing interest. Many of works, using a variety of approaches, conclude that there is often discrimination and injustice. However, from the public decision-making and governance perspective, one question needs a clear answer: how much inequality is there? Is this too much, and therefore unfair, and does it justify public action? This paper looks at this question in a case study on the threat posed by air pollution in Madrid and Barcelona (Spain), by examining the spatial distribution of several vulnerable population groups and their potential exposure to high concentrations of PM10 in the atmosphere, and using an affordable method involving GIS and statistical techniques. Adopting an explicitly impartial operating criterion makes it possible to measure the amount of inequality for each population group and determine more objectively if it significantly exceeds the baseline criterion. This would make it more accurate for citizens and decision-makers alike to better assess the possible inequitiesLas desigualdades en la afección o carga ambiental (externalidades negativas, peligros, malestar, etc.) entre lugares y personas son un tema de creciente interés. Se han publicado abundantes estudios, utilizando métodos diversos, en los que se concluye que, a menudo, existe discriminación e inequidad. Ahora bien, desde el punto el punto de vista de la formación de decisiones públicas y de la gobernanza una pregunta sigue siendo necesario responder con claridad: cuánta desigualdad existe y si ésta es demasiada para ser calificada de injusta y justificar, por tanto, la acción pública. En este artículo se aborda esa cuestión a partir de un estudio de caso relativo al peligro por polución del aire en Madrid y Barcelona (España). A tal fin se examina la distribución espacial de varios grupos de población vulnerables y su exposición potencial a alta concentración de PM10 en la atmósfera, usando un método razonable que implica el uso de SIG y técnicas estadísticas. La adopción de un criterio operativo y explícito de imparcialidad posibilita medir la cantidad de desigualdad para cada grupo de población y determinar si ésta excede significativamente al criterio de referencia. Ello facilita una valoración más certera de la situación por los ciudadanos y los decisores públicosThis research was supported by the Spanish Ministry of Economy, Industry and Competitiveness project grant CSO2014-55535-