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Focused Assessment with Sonography for Trauma (commonly abbreviated as FAST) is considered for patients with blunt abdominal trauma as the gold standard for accident assessment in site. This method is increasingly used even by not radiologists professionals, as well as by nurses who works in emergency settings. This systematic review is aimed at evaluating the effectiveness of ultrasound FAST performed by nurses in emergencies department. Seven databases of primary and secondary literature as well as three national journals relevant to the field were consulted. The review was conducted between March and August 2011 developing 9 search strings. Articles have been critically reviewed by two authors independently. No restriction on language or time of publication have been used. A total of 4767 documents were displayed, of those only 4 were considered to be reviewed. A total of 1035 FAST ultrasound performed by nurses were included. The results show that the use of ultrasound FAST performed by trained nurses is very effective, with a sensitivity of 84% (95% CI 72.1-92.2) and a specificity of 97.37% (95% CI 92.55-99.10) . Practice execution time was an average of 156 seconds (2.6 minutes), median time of 138 seconds (range = 76 to 357). Just one study specified the training course that nurses were required to attend. To sum up, FAST ultrasound performed by nurses have an important role in emergencies management as well as in triage setting as valid screening tool.

Triphasic waves (TWs) are a distinctive, although non-specific EEG pattern, which are quite frequently encountered and sometimes difficult to interpret. Although initially considered pathognomonic of hepatic encephalopathy, TWs have been described in association with a large number of conditions. TWs may occur in encephalopathies (metabolic or structural) or as an ictal pattern. Nonepileptic TWs with sharply contoured morphology may resemble epileptic patterns encountered in nonconvulsive status epilepticus (NCSE), thus leading to misinterpretation and overinterpretation of this pattern as ictal, if only the EEG is considered. An electroclinical response to benzodiazepines and the evaluation of consciousness impairment should be considered when interpreting TWs. Evaluating only the EEG without considering also clinical and laboratory findings is not only useless and meaningless, but may even lead to serious consequences.

Sloshing of fluids with a free surface contained in liquid storage tanks is numerically simulated by an arbitrary Lagrangian-Eulerian formulation. The fluid is considered viscous and Newtonian, while the flow is assumed laminar and incompressible. A partitioned and distributed computational code is employed, which solves three instances each time step: (i) the determination of the fluid state, given by the Navier–Stokes equations, (ii) the displacement of the free surface, and (iii) the update of the position of the internal nodes of the mesh, that is deformed as a consequence of the free surface displacement. The purpose of the work is verifying the applicability of the method to sloshing problems with known solutions, as well as the resolution of some practical examples. Numerical examples include validations against analytical solutions, where the wave period and damping rate are well captured, comparisons with reference results from other authors and a sample of sloshing induced by seismic actions.

The unsteady flow around a 155 mm projectile governed by the Navier-Stokes (NS) equations is numerically solved with a Large Eddy Simulation (LES) scheme, together with the SubGrid Scale (SGS) solved by a Smagorinsky model and the van Driest near-wall damping. The computed results are obtained in the subsonic flow regime for a viscous and incompressible Newtonian fluid in order to determine the axial drag coefficient, and they are validated against experimental data. The problem was solved by a monolithic finite element code for parallel computing on a Beowulf cluster. Fil: Garibaldi, J.. Ministerio de Defensa. Instituto de Investigaciones Científicas y Técnicas para la Defensa; Argentina Fil: Storti, Mario Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Battaglia, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: D'elia, Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

A meshless method is presented for the solution of the incompressible fluid flow equation using a lagrangian formulation. The interpolated function are those used in the moving least square approximations and the time integration is introduced in a semi-implicit way by a fractional step method. Both classical stabilization terms used in incompressible Navier-Stokes equations are unnecessary: numerical diffusion for convective terms are unnecessary due to the lagrangian formulation, and stabilization of pressure due to the incompressibility constraint for equal order interpolations is eliminated using the fractional step method.

Se describe la formulación de un modelo computacional para determinar, bajo condiciones invíscidas, el flujo tridimensional alrededor de la pala de una turbina eólica de eje horizontal. Dicho modelo se basa en la representación mediante paneles de una pala rígida, delgada, torsionada y de envergadura finita. A estos paneles se asocian hilos vorticosos rectos, que conforman el sistema ligado a la pala, y un sistema de hilos vorticosos libres, que presentan trayectorias helicoidales de radios no constantes, que determinan una estela de configuración fija. Las velocidades inducidas por el sistema vorticoso completo son calculadas por la aplicación de la ley de Biot-Savart. Se presenta la metodología seguida para el cálculo de las distribuciones de circulación, velocidades inducidas y resultantes y cargas aerodinámicas a lo largo de la envergadura y cuerda de una pala de geometría definida, bajo una determinada condición de viento y rotación uniformes, sin la consideración de los efectos de interferencia. This work describes the formulation of a computational model to detemine, under inviscid conditions, the tri-dimensional flow field around the blade of an horizontal-axis wind turbine. The model is based upon a panel representation of a rigid, thin and twisted blade of finite span.The distribution of circulation is originated by a system of straight bound vortices associated to the blade and a system of free vortex filaments, having helical paths with non-constant radii, that generates a prescribed fixed wake. The velocities induced by that vortex system are calculated by the Biot-Savart law. The methodology followed in order to calculate the span and chordwise distributions of circulation, induced velocities and aerodynamic loads is presented for a blade whose geometry and working conditions are defined, without considering the interference effects.

Presentamos un esquema de discretización basado en la formulación Petrov-Galerkin para, problemas de reacción-advección-difusión. El esquema presentado exhibe superconvergencia, (valores exactos en los nodos) para una cierta clase restringida de problemas unidimensionales, de la misma forma que ocurre con SUBG cuando el parámetro de upwind es elegido a través de la "función mágica". Estos resultados son extendidos a sistemas de ecuaciones. Como caso particular mostramos la aplicación a las ecuaciones simplificadas que rigen los flujos viscosos en sistemas de rotación (capa límite de Eckman). Se presentan ejemplos numéricos uni- y bidimensionales, con y sin fuente, y también en el contexto de la capa límete de Eckman.

En trabajos recientes se han propuesto un método de dominio fijo y sin paramétros de regularización para tratar el problema de transmisión del calor con cambio de fase. En este trabajo se estudia la aplicación de la familia de métodos x de integración temporal a esa misma discretización. Particular atención se dedica al método explicito,para el cual es imprecindible el agregado de la matriz de capacidad de interfase a la matriz de capacidad clásica. El criterio de elección del paso de tiempo para obtener estabilidad es simple y confiable. Finalmente se presentan ejemplos numéricos que permiten comparar la efieciencia de los diferentes esquemas analizados.

Son considerados flujos alrededor de perfiles aerodinámicos que evolucionan en el tiempo en forma rígida. Para evitar el uso de mallas deformables la ecuación potencial completa es transformada a un sistema de referencia no-inercial donde el dominio de integración es fijo. En este sistema las ecuaciones son discretizadas y resueltas por un método de minimización en direcciones dadas por los vectores de Lanczos. Para casos con sustentación se tiene en cuenta la vorticidad concentrada en el borde de fuga siguiendo el modelo de Giesing-Maskeli el cual, para frecuencias reducidas muy pequeñas, es equivalente a la condición de Kutta-Joukowski estacionaria. Varios ejemplos numéricos son presentados. In this work inviscid irrotational flows around aerodynamic profiles which experiment rigid motions are studied. To avoid the use of deformable grids the fuli potential equation is transformed to a non-inertial frame of reference where the domain of integration is fixed. The problem is discretized in this frame of reference and the resulting system of equations is resolved via a minimization along Lanczos vectors algorithm. In lift problems, the vorticity concentrated in the wake is taken account. This vorticity is produced in the trailing edge foilowing the model of Giesing & Maskeil, which reduces to the steady Kutta-Joukowski condition for low reduced frequencies. Finally several numerical examples are presented.