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Damage formation is investigated in GaAs implanted with 1 MeV Si ions to ion fluences from 3 × 10¹² to 5 × 10¹⁵ cm⁻² at room temperature. Under the conditions applied, amorphization of the implanted layers does not occur. The weakly damaged layers are studied by applying different experimental techniques including Rutherford backscattering spectrometry in channeling configuration, x-ray diffraction, in situ curvature measurement, optical subgap spectroscopy, and transmission electron microscopy. The results are evaluated and quantitatively connected with each other. Damage formation is described as a function of the ion fluence using a common defect evolution model. Point defects and defect clusters have to be taken into account in the ion fluence range of main interest up to 2 × 10¹⁵ cm⁻². Point defects contribute by a factor of about 8 more to both perpendicular strain and in-plane stress than defect clusters. When the concentration of point defects or the induced strain reaches a critical value, defect clusters form, which ensures that no further increase of perpendicular strain occurs. This reveals a clear driving force for cluster formation. The microstructure of the defect clusters cannot be determined from the results. As₃Ga₂ interstitial clusters are supposed. A remarkable decrease of the shear modulus of the implanted layers below the value of pristine GaAs by ≈ −35% is observed. Surprisingly, the change of shear modulus already sets in at a very low damage level of a few percent

Una vez valorada la indicación del tratamiento antiagregante y el riesgo tromboembólico en anteriores entradas, este último, bajo niveles de evidencia III o IV, debemos conocer y valorar el riesgo hemorrágico del procedimiento al que será sometido el paciente si decidimos no suspender los antiplaquetarios con el fin de llegar al último punto del proceso de decisión con todos los argumentos necesarios para, desde un punto de vista multidisciplinario, individualizando e informando adecuadamente al paciente, consensuar la decisión de retirar o continuar la terapia antiagregante.

This study is a good demonstration on how complementary EFD and CFD can provide a powerful and advanced tool in analyzing complex industrial flows. Results are presented from a cooperative study between INSEAN and IIHR about wave and flow field measurement about a surface combatant with focus on the 3D ship wave breaking. At Fr-0.35, free-surface near and far fields have been measured, as well as the velocity in some transversal planes under the bow and shoulder wave. CFD computations have also been used to complete and extend EFD data and to understand some particular features of the flow, such as location of vortices near the free-surface and scars.