Summary This ongoing Dutch study into the school careers of young children in primary schools has focused in part on the influence of school and class organisation on linguistic and cognitive development. In the first year of the study, data on the school and class characteristics were gathered in 28 primary schools by means of questionnaires, interviews, journals and observation. A multi-level analysis shows that differences in pupil achievements between classes already exist at the beginning of primary school, but that (...) these differences are, to a large extent, explained by the characteristics of the pupils? backgrounds. The Dutch vocabulary of pupils at the end of their first year is mainly determined by earlier linguistic achievement and the ethnicity and SES of the pupil, rather than the school or class organisation. The scores on a performance intelligence test (block patterns) at the end of the first year could not be exclusively explained by the pupils? background characteristics but also by some school characteristics. (shrink)

A geometric formulation of the gravitation theory in the spacetime R × S 3 is given. A linear connection is introduced on the tangent bundle T(R × S 3 ) and then the connection coefficients and the Riemann curvature tensor are calculated. It is shown that their expressions differ from those of Carmeli and Malin [Found. Phys.17, 407 (1987)] by supplementary terms due to the noncommutativity of derivatives used on the spacetime R × S 3 . The Einstein field equations (...) are written as usually and a comparison with other results is given. Finally, some observations about a possible gauge theory of gravitation in the spacetime R × S 3 are made. (shrink)

Mathematical modeling is a convenient way for characterization of complex ecosystems. This approach was applied to study the dynamics of zooplankton in Lake Sevan (Armenia) at different stages of anthropogenic eutrophication with the use of a novel method called discrete modeling of dynamical systems with feedback (DMDS). Simulation demonstrated that the application of this method helps in characterization of inter- and intra-component relationships in a natural ecosystem. This method describes all possible pairwise inter-component relationships like “plus–plus,” “minus–minus,” “plus–minus,” “plus–zero,” “minus–zero,” (...) and “zero–zero” that occur in most ecosystems. Based on the results, a working hypothesis was formulated. It was found that the sensitivity to weak external influence in zooplanktons was the greatest during the mid period of eutrophication in Lake Sevan, whereas in the final stages of eutrophication, an outbreak in the biomass production of cyanobacteria was evident. To support this approach, a weak external disturbance in the form of magnetic storm was used to see its effect on species Daphnia longispina sevanica. A statistically significant correlation between the frequency of magnetic storms and the number of this species was revealed and an increase in the number of toxic cyanobacteria species as a consequence of eutrophication. This paper, for the first time, suggests a DMDS method, to diagnose impact of anthropogenic eutrophication on environment. (shrink)

Keine ausführliche Beschreibung für "Über das Wesen der Naturgesetze" verfügbar.

A lyrical variation on vv. 27–30, the present passage is, at the same time, a new version of Hec. 631–7. A comparison is instructive in various respects, but Hel. 27 f. will not be quoted in justification of what L gives in vv. 236 f. This wording raises the following objections: the last word, , is outside the metre and not easily attached to the following colon, the beginning of which naturally coincides with the new sentence and new idea If, (...) then, is obelized—and this seems unavoidable—the words. (shrink)

Due to its extraordinary predictive power and the great generality of its mathematical structure, quantum theory is able, at least in principle, to describe all the microscopic and macroscopic properties of the physical world, from the subatomic to the cosmological level. Nevertheless, ever since the Copen hagen and Gottingen schools in 1927 gave it the definitive formu lation, now commonly known as the orthodox interpretation, the theory has suffered from very serious logical and epistemologi cal problems. These shortcomings were immediately (...) pointed out by some of the principal founders themselves of quantum theory, to wit, Planck, Einstein, Ehrenfest, Schrodinger, and de Broglie, and by the philosopher Karl Popper, who assumed a position of radical criticism with regard to the standard formulation of the theory. The aim of the participants in the workshop on Open Questions in Quantum Physics, which was held in Bari (Italy), in the Department of Physics of the University, during May 1983 and whose Proceedings are collected in the present volume, accord ingly was to discuss the formal, the physical and the epistemo logical difficulties of quantum theory in the light of recent crucial developments and to propose some possible resolutions of three basic conceptual dilemmas, which are posed respectively ~: (a) the physical developments of the Einstein-Podolsky-Rosen argument and Bell's theorem, i. e. (shrink)

First published in 2002. Routledge is an imprint of Taylor & Francis, an informa company.