In this paper we consider two related objects: singular positive semidefinite Hankel block–matrices and associated degenerate truncated matrix Hamburger moment problems. The description of all solutions of a degenerate matrix Hamburger moment problem is given in terms of a linear fractional transformation. The case of interest is the Hamburger moment problem whose Hankel block–matrix admits a p...

Recent studies of dietary habits in children and adolescents performed in Spain show that a high percentage of the daily energy intake corresponds to fat (42.0-43.0%). These findings show an excessive contribution of saturated fatty acids and also a considerable supply of trans fatty acids. These compounds are formed generally during partial hydrogenation of vegetable oils, a process that conve...

In this paper Viktor Hamburger [5] and Rita Levi-Montalcini [6] collaborated to examine the effects of limb transplantation [7] and explantation on neural development [8]. In 1947 Hamburger invited Levi-Montalcini to his lab at Washington University [9] in St. Louis to examine this question. Independently, each had previously arrived at opposing conclusions based on the same data. Hamburger con...

In 1951 Viktor Hamburger [4] and Howard Hamilton created an embryonic staging series from a combination of photographs and drawings from other researchers. The Hamburger?Hamilton stages are a sequence of images depicting 46 chronological stages in chick [5] development. The images begin with a fertilized egg [6] and end with a fully developed chick [5]. The Hamburger-Hamilton staging series was...