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THERE is probably no one among those listening to me this evening who does not know, or who has not realised through personal experience, the importance of the problem of detonation in internal combustion engine technique. Indeed, since petrol engines have been working on the Beau do Rochas cycle, the phenomenon of “knocking” has been an obstacle—which has gradually been driven into the background, it is true, but which is really insurmountable—to the increase in compression which is recommended by thermodynamics and which experience has shown to produce an increase in output equal to, and even slightly in excess of, the calculated theoretical value.

The measurement of small deflections, the most important duty of measurement technics in aeronautical research, may be executed very simply and rapidly by a scratch record of the motions—in as far as possible in natural size— on a suitable inscribing surface, the record being subsequently analysed under the microscope or lens or by microphotographic means. A whole series of measuring instruments of the scratch recording type have been evolved to serve the most diverse purposes in aeronautical research. These are described in this report, the degree of accuracy obtainable in each case being examined.

The Council of the Air Registration Board announces the issue of Notice to Licensed Aircraft Engineers and to Owners to Civil Aircraft, No. 10, Issue 4, dated January 1, 1950, which reads as follows:

M Alayrac gives here the further results of his investigations of irrotational three dimensional flow of which he has already written in Publications Scientifiques Nos. 3 and 13 (cf. abstracts in AIRCRAFT ENGINEERING, Vol. IV, Nos. 38 and 42, March and December, 1932). The examples already dealt with show that the flow about a finite surface even with high aspect ratio differs very widely from uniplanar flow. The final purpose of the work is not, however, to find the sole flow, with given velocity at infinity and finite velocity at every point, for this flow being non‐productive of resistance is of no interest from the point of view of aero‐dynamics, but it is defined as the search for flows with points, lines or surfaces of infinite velocity which have no sense in perfect fluids but which are acceptable in viscous fluids, the regions of infinite velocity being replaced by regions of turbulence.

Author's preference for use of term magnetofluidmechanics instead of magnctohydromechanics; résumé of main principles; applications of the science in astronautics.

The following abstract of the report issued by the board appointed by the Secretary of Commerce to investigate an accident to a Lockheed 14‐H aeroplane on January 10, 1938, is taken from the “ Air Commerce Bulletin,” Vol. 9, No. 8, February 15, 1938 :—

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee. Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics and publications of other similar research bodies as issued

The purpose of this paper is to extend the h-index framework to the case that articles are counted fractionally.

Three restrictions related to the standard h-index are explained: as the standard h-index is a natural number it is a rather coarse indicator; if a scientist has published a relatively small number of publications then the h-index is completely determined by the number of publications; the standard h-index cannot be applied if publications are counted fractionally, or when magnitude values smaller than one occur.

We recall solutions we proposed in earlier publications regarding the first two problems (the use of the interpolated h-index and of the pseudo h-index) and add a new proposal to solve the third problem. The relation between the recently introduced window/field-normalized h-type index (hwf-index) and the interpolated h-index is described. A real-world example proves the feasibility of this proposal.

Colleagues have shown that the h-index and its variations have fatal flaws and hence should never be used. Yet, not everyone agrees with this opinion.

Assuming that the h-index still has some value, this paper introduces a refinement of the interpolated h-index, called the generalized interpolated h-index. In this way the h-index framework is extended to incorporate, for instance, the case that fractional counting for publications and citations is applied.

THE universal topic of the moment in England is the apparent decision of the British Government to obtain aeroplanes for the Royal Air Force from the United States.

Stent malapposition is one of the most significant precursors of stent thrombosis and restenosis. Adverse haemodynamics may play a key role in establishing these diseases, although numerical studies have used idealised drug transport models to show that drug transport from malapposed drug-eluting stent struts can be significant. This paper aims to study whether drug transport from malapposed struts is truly significant. Another aim is to see whether a streamlined strut profile geometry – with a 61% smaller coating but a 32% greater coating-tissue contact area – can mitigate the adverse haemodynamics associated with stent malapposition while enhancing drug uptake.

Two- and three-dimensional computational fluid dynamics simulations were used in this study. Unlike past simulations of malapposed drug-eluting stent struts, a qualitatively validated drug-transport model which simulates the non-uniform depletion of drug within the drug coating was implemented.

It was shown that even a 10-µm gap between the strut and tissue dramatically reduces drug uptake after 24 h of simulated drug transport. Furthermore, the streamlined strut profile was shown to minimise the adverse haemodynamics of malapposed and well-apposed stent struts alike and enhance drug uptake.

Unlike prior numerical studies of malapposed stent struts, which did not model the depletion of drug in the drug coating, it was found that stent malapposition yields negligible drug uptake. The proposed semicircular-profiled strut was also shown to be advantageous from a haemodynamic and drug transport perspective.