The apid cuckoo bees of the Cape Verde Islands (Republic of Cape Verde) are reviewed and five species recognized, representing two genera. The ammobatine genus Chiasmognathus Engel (Nomadinae: Ammobatini), a specialized lineage of cleptoparasites of nomioidine bees is recorded for the first time. Chiasmognathus batelkaisp. n. is distinguished from mainland African and Asian species. The genus T...

The Extended Engel Expansion is an algorithm that leads to unique series expansions of q-series. Various examples related to classical partition theorems, including the RogersRamanujan identities, have been given recently. The object of this paper is to show that the new and elegant Rogers-Ramanujan generalization found by Garrett, Ismail, and Stanton also ts into this framework. This not only ...

The Extended Engel Expansion is an algorithm that leads to unique series expansions of q-series. Various examples related to classical partition theorems, including the Rogers-Ramanujan identities, have been given recently. The object of this paper is to show that the new and elegant Rogers-Ramanujan generalization found by Garrett, Ismail, and Stanton also ts into this framework. This not only...

By relating Engel curves and social learning, we explain the existence of differently shaped Engel curves—an interesting phenomenon in the theory of demand. A formal approach to cultural learning within a population of consumers accounts for some cognitive foundations of these demand patterns. We find that a changing influence of an individual’s role models due to her increasing income, which e...

On the observation of mesospheric air inside the arctic stratospheric polar vortex in early 2003 A. Engel, T. Möbius, H.-P. Haase, H. Bönisch, T. Wetter, U. Schmidt, I. Levin, T. Reddmann, H. Oelhaf, G. Wetzel, K. Grunow, N. Huret, and M. Pirre Institut für Atmosphäre und Umwelt, J. W. Goethe Universität Frankfurt, Frankfurt, Germany Institut für Umweltphysik, Ruprecht – Karls Universität Heide...

This paper revisits Ernst Engel’s (1857) original article in which he systematically investigated the relationship between consumption expenditure and income. While he is mainly remembered today for the discovery of Engel’s law, we highlight how Engel addressed in a particular way the issue of the relation between statistical empirical analysis and economic theorizing. Inspired by an inductive ...

a famous theorem of schur states that for a group $g$ finiteness of $g/z(g)$‎ ‎implies the finiteness of $g'.$ the converse of schur's theorem is an interesting problem which has been considered by some‎ ‎authors‎. ‎recently‎, ‎podoski and szegedy proved the truth of the converse of schur's theorem for capable groups‎. ‎they also established an explicit bound for the index of the center of such...