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Deafness, with its personal and social burden, has certainly accompanied mankind since the beginning of its existence, meaning that various natural aids to hearing, the cupped human hand the first among them, have assuredly been in use since antiquity. Ear trumpets were essentially the first totally artificial type of hearing aid. The actual history of ear trumpets seems to have begun in the seventeenth century, when written evidence on the matter first appears. The French Jesuit Jean Leurechon, in his Recreation Mathematique of 1624, first mentions funnel-like objects as sound amplifiers, while Sir Francis Bacon, in his Sylva Sylvarum, published in 1627, clearly states that similar objects were already in use as aids to hearing. Giovanni Battista della Porta, in his oft-cited Magiae Naturalis of 1589, offers only a vague and inconclusive description of an aid that would once again imitate natural shell forms and can only be considered as one of the first published references to sound amplification. This work focuses on the contribution of Galileo’s disciple Paolo Aproino who, around 1612–13, presented to Galileo, and through this latter to the court of the Grand duke of Tuscany, an auditory instrument that amplified sound, together with his pioneering experimental studies in the field. Using the experimental method taught by Galileo, Aproino was able to test various forms and materials, deciding upon the final design of the instrument that he then supplied to Galileo in order to construct a metal prototype. This trumpet-like linear ear horn seemed to obtain good results in sound amplification, even though it entailed a certain amount of sound distortion that somewhat reduced the intelligibility of speech. Although Aproino never produced any publications on the matter, his findings became known and impressed the scientific and literary milieu of his time and could therefore have been the initial spur for the future development of sound amplification in the following years. [ABSTRACT FROM PUBLISHER]

Abstract: The dynamic response of piles to seismic loading is explored by means of an extensive parametric study based on a properly calibrated Beam-on-Dynamic-Winkler-Foundation (BDWF) model. The investigated problem consists of a single vertical cylindrical pile, modelled as an Euler–Bernoulli beam, embedded in a subsoil consisting of two homogeneous viscoelastic layers of sharply different stiffness resting on a rigid stratum. The system is subjected to vertically propagating seismic S waves, in the form of a transient motion imposed on rock outcrop. Several accelerograms recorded in Italy are employed as input motions in the numerical analyses. The paper highlights the severity of kinematic pile bending in the vicinity of the interface separating the two soil layers. In addition to factors already investigated such as layer stiffness contrast, relative soil–pile stiffness, interface depth and intensity of ground excitation, the paper focuses on additional important factors, notably soil material damping, stiffness of Winkler springs and frequency content of earthquake excitation. Existing predictive equations for assessing kinematic pile bending at soil layer interfaces are revisited and new regression analyses are performed. A synthesis of findings in terms of a set of simple equations is provided. The use of these equations is discussed through examples. [Copyright &y& Elsevier]

This article presents a study which aims at analyzing the policies and the tactics of two European medium sized city regions to apply a sustainable sound pattern of development. Both cities are located in industrialized areas: Bochum in the Valley of Ruhr in Germany and Modena in the region of Emilia-Romagna. Similarities can be detected such as the environmental threats and the common cultural and political context. The article compares these cases and provides contrasts and similarities stemming from the two different developmental patterns.