Abstract This theoretical and experimental work deals with the power law evolution followed by the natural frequency f 0 of a hanging, heavy and flexible plate as a function of its length L. When the plate length L is small enough, it behaves as an elastic plate whose weight can be neglected: it is well known that f 0 evolves as a function of L − 2. Nevertheless, when the plate length is increased, the mass has to be taken into account, and the previous evolution is not valid anymore. In the case of long elastic plates, f 0 ∼ L − 1 / 2, just like hanging chains. These two power laws depend on the ratio L / L c, where L c is a critical length that writes as a function of the plate mass and the flexural rigidity. After the theory is developed and the plate motion equation is solved using a Galerkin expansion, we find the theoretical evolution of the natural frequencies as a function of length. Experiments were performed with three distinct materials and the natural frequency was systematically measured for a wide length interval. Our data points fit the above-mentioned limit cases and the intermediate case was calculated thanks to our Galerkin expansion.

Una causa común de morbilidad y mortalidad atribuible a la anestesia es la intubación dificultosa o fallida. Si se identifica previamente a los pacientes en condiciones de riesgo, un anestesista con un equipo preparado puede estar presente para enfrentarse a este problema. Los anestesistas deben tener el conocimiento y entrenamiento en seleccionar racionalmente los métodos de manejo de la vía aérea y realizarlos rápidamente y secuencialmente como sea requerido. Se desarrollan las distintas técnicas que se deben considerar en esta situación.

A common cause of morbidity and mortality attributable to anaesthesia is difficult or failed intubation. If those patients in whom intubation proves difficult could be identified in advanced, it could be arranged that an anesthetist properly equipped could be present to deal with the problem. Anesthetists are advised to become knowledgeable and skillful in selected rational methods of airway management and institute them sequentially and rapidly as required. The techniques to consider in this situation are reviewed