We report a scanning tunnelling microscopy investigation of the emission of dislocations around nanoindentations in the form of dislocation arrangements previously called hillocks , consisting of two pairs of Shockley partial dislocations, each encompassing a stacking fault. The spatial arrangement and size distribution of hillocks around the nanoindentation traces are studied. We show that standard dislocation theory for an isotropic continuum can be used to describe the stability of the hillocks, their size and spatial distribution and the broadening of the (...) corresponding extended dislocations near the surface. A model is proposed in which hillocks originate from the split into dislocations partials of primary perfect dislocation loops punched into the crystal by the scanning tunnelling microscope tip. This model implies the operation of a novel dislocation mechanism involving long-range transport of matter across the surface. (shrink)

The consideration of racial differences in the biology of disease and treatment options is a hallmark of modern medicine. However, this time-honored medical tradition has no scientific basis, and the premise itself, that is, the existence of biological differences between the commonly known races, is false inasmuch as races are only sociocultural constructions. It is time to rid medical research of the highly damaging exercise of searching for supposed racial differences in the biological manifestations of disease. The practice not only (...) condoned but required by the National Institutes of Health of utilizing racial identification as a demographic characteristic with assumed biological implications is at best badly flawed, and at worst unintentionally contributes to perpetuating the fallacy of natural differences between persons of different skin color, which has been used in the past to advance the cause of racial discrimination. (shrink)

The consideration of racial differences in the biology of disease and treatment options is a hallmark of modern medicine. However, this time-honored medical tradition has no scientific basis, and the premise itself, that is, the existence of biological differences between the commonly known races, is false inasmuch as races are only sociocultural constructions. It is time to rid medical research of the highly damaging exercise of searching for supposed racial differences in the biological manifestations of disease. The practice not only (...) condoned but required by the National Institutes of Health of utilizing racial identification as a demographic characteristic with assumed biological implications is at best badly flawed, and at worst unintentionally contributes to perpetuating the fallacy of natural differences between persons of different skin color, which has been used in the past to advance the cause of racial discrimination. (shrink)

The aim of this research was to delimit the predictive and mediational model of resilience between character strengths to predict flourishing, in a sample of undergraduate students. After signing their informed consent, 642 university students completed three validated scales. Using an ex post facto design, regression, structural modeling, and mediation analyses were carried out, in order to construct a multi-causal predictive model. Results indicated a consistent predictive direct effect of character strengths on resilience and flourishing and of resilience on flourishing. (...) As hypothesized, resilience also showed a mediating effect on the relationship between character strengths and flourishing. Additionally, results also revealed that the reactive and proactive factors of resilience were explained by different character strengths, reinforcing the idea that the two directions are complementary and necessary. Finally, several implications were established for the practice of positive psychology. (shrink)

Este artículo de homenaje a la Profesora Yolanda Ruano se divide en dos partes. En la primera discuto las críticas que ella realizara a mi libro sobre la diosa Fortuna en las que avanzaba su propio análisis de las complejas relaciones entre razón y fortuna en el pensamiento occidental. En la segunda parte, desde el punto de vista del “giro icónico” en humanidades y ciencias sociales, analizo el caso concreto del auge y desaparición de la diosa Fortuna en la iconografía (...) política de la ciudad de Berlín. A lo largo del siglo XIX la diosa Fortuna desaparece de la escena berlinesa y es sustituida por la diosa Niké o Victoria, que popularmente se interpreta como un Ángel de la Victoria. Este es el marco de la infancia de Walter Benjamin, quien más tarde expresará su visión de la historia con un otro ángel completamente distinto, el Angelus Novus de Paul Klee. (shrink)