In 1959 Ernst Mayr challenged the relevance of mathematical models to evolutionary studies and was answered by JBS Haldane in a witty and convincing essay. Fifty years on, I conclude that the importance of mathematics has in fact increased and will continue to do so.

We examine market making behavior of dealers for a sample of 55,988 corporate bonds, many of which trade infrequently. Dealers have a substantially higher propensity to offset trades within the same day rather than committing capital for longer periods, particularly for riskier and less actively traded bonds. Dealers’ holding periods do not decline with liquidity, and in fact are lowest for som...

A routine detailed ultrasound examination performed at 20 weeks' gestation demonstrated the presence of nuchal thickening as an apparently isolated finding. The concentration of maternal alpha-fetoprotein was normal and the risk of Down's syndrome was 1 in 6800. Amniocentesis was performed and chromosome analysis showed the karyotype 46,XY, del(11)(q23) found in Jacobsen syndrome. Fetal autopsy...

AND EXTANT U-Pb SYSTEMATICS IN THE EARLY SOLAR SYSTEM. Qing-Zhu Yin, Yuri Amelin, and Benjamin Jacobsen, Department of Geology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA ([email protected], [email protected]), Research School of Earth Sciences, Australian National University, Building 61, Mills Road, Canberra, ACT 0200, Australia (yuri.amelin@anu...

We describe a 34-year-old male patient with Jacobsen syndrome associated with a broad spectrum of anomalies and an increased susceptibility to infections. Features commonly seen in Jacobsen syndrome were short stature, mental retardation, congenital heart disease, cryptorchidism, strabismus, distal hypospadia glandis, and mild thrombocytopenia. Chromosome analysis disclosed a mosaic 46,XY,del(1...

Robert Jacobsen, Bd. 1: Biographische Skizzen, hrsg. vom Museum Würth durch Lothar Romain undC. Sylvia Weber, Sigmaringen (Thorbecke) 1992, 119 S.
 2: Werke aus 50 Jahren, und C. 135 S.

Jacobsen distributor, he knows that the sale doesn't end with delivery. In fact, it's just beginning. The rest of it depends upon his ability to give you fast service whenever it's needed. He knows that when your equipment is out for service, it's like having no equipment at all. That's why your Jacobsen distributor goes out of his way to offer you the best service in the business. From normal ...