The celestial mechanics of Leibniz in the light of Newtonian criticism

By the middle of the nineteenth century science was developing into a profession demanding advanced training and devotion to research. American institutions, however, were still better suited to an earlier stage of popular science. Many of the difficulties and frustrations for would-be scientists created by the time lag in institutional change are illustrated in the career of Cleveland Abbe. In the fifteen years between 1856 and 1871 his attempts to become an astronomer touched upon many significant aspects of American science as a profession, including the American observatory movement, the creation of graduate education, government support for science, and the tension between the joint goals of the increase and the diffusion of knowledge.     

The adoption of self-induction by telephony, 1886–1889

Through 1886 to 1889 understanding of the mechanism of telephone transmission was transformed from an electrostatic and traditional view to an electrodynamic one conforming with Maxwell's scheme. Observed at the level of commercial application this painful adjustment occurred via a sequence of controversies connected with self-induction—on techniques of telephony, on electrical measurement, on lightning conductors and on matters of professional ethics—in which the parts played by evidence, by theory, and by authority were strangely mixed. The well-known confrontation of O. Heaviside and W. H. Preece was at the centre of the debate. An open division between traditionalists and progressives amongst electrical engineers was provoked, and the effectiveness of mathematical theory as against pure pragmatism at the practical level had in the end to be conceded.     

Structural basis of bacterial defense against g-type lysozyme-based innate immunity

Gram-negative bacteria can produce specific proteinaceous inhibitors to defend themselves against the lytic action of host lysozymes. So far, four different lysozyme inhibitor families have been identified. Here, we report the crystal structure of the Escherichia coli periplasmic lysozyme inhibitor of g-type lysozyme (PliG-Ec) in complex with Atlantic salmon g-type lysozyme (SalG) at a resolution of 0.95 Å, which is exceptionally high for a complex of two proteins. The structure reveals for the first time the mechanism of g-type lysozyme inhibition by the PliG family. The latter contains two specific conserved regions that are essential for its inhibitory activity. The inhibitory complex formation is based on a double ‘key-lock’ mechanism. The first key-lock element is formed by the insertion of two conserved PliG regions into the active site of the lysozyme. The second element is defined by a distinct pocket of PliG accommodating a lysozyme loop. Computational analysis indicates that this pocket represents a suitable site for small molecule binding, which opens an avenue for the development of novel antibacterial agents that suppress the inhibitory activity of PliG.