Koinonia in die stad: Verhoudinge in die groter stadsgemeentes van die Gereformeerde kerke

Koinonia in the city: Relations in the larger urban congregations of the Reformed churchesKoinonia is of vital importance for the church. It is not only a Biblical injunction, but also, sociologically speaking, a prerequisite for the preservation of faith in theChristian community. Therefore it is imperative that the church’s ministry encourages koinonia. This is especially true for the church in an urban context, where relational networks have been severely impaired. The traditional pattern of ministry of churches in the Reformed tradition, the shepherd-flock model, does not succeed in stimulating koinonia under these circumstances. Therefore, the choice is rather made for the body of Christ-model, with complementary koinonia-groupings as theory of practice

The conduction pathway of potassium channels is water free under physiological conditions.

Ion conduction through potassium channels is a fundamental process of life. On the basis of crystallographic data, it was originally proposed that potassium ions and water molecules are transported through the selectivity filter in an alternating arrangement, suggesting a "water-mediated" knock-on mechanism. Later on, this view was challenged by results from molecular dynamics simulations that revealed a "direct" knock-on mechanism where ions are in direct contact. Using solid-state nuclear magnetic resonance techniques tailored to characterize the interaction between water molecules and the ion channel, we show here that the selectivity filter of a potassium channel is free of water under physiological conditions. Our results are fully consistent with the direct knock-on mechanism of ion conduction but contradict the previously proposed water-mediated knock-on mechanism

Properties of 3-manifolds for relativists

In canonical quantum gravity certain topological properties of 3-manifolds are of interest. This article gives an account of those properties which have so far received sufficient attention, especially those concerning the diffeomorphism groups of 3-manifolds. We give a summary of these properties and list some old and new results concerning them. The appendix contains a discussion of the group of large diffeomorphisms of the $l$-handle 3-manifold.Comment: 20 pages. Plain-TeX, no figures, 1 Table (A4 format

Is it more feeling or thinking? The influence of affective and cognitive attitude on adolescents' intention to engage in binge drinking

Previous work has revealed that interventions aiming to reduce adolescent binge drinking commonly focus on cognitive attitudes, but are insufficiently effective in changing binge-drinking intentions. The focus on these cognitive attitudes might be the reason for this insufficient success. That is, other work has revealed that affective attitudes have a stronger influence on binge-drinking intention than cognitive attitudes. However, this relation has so far only been found among traditional college students and pre-vocational school students, therewith neglecting another important population at risk, namely vocational community college students. This study examines whether affective attitudes are also significantly stronger influencers of binge-drinking intentions among vocational community college students. Using a sample of 298 vocational community college students (Mage = 17.63), the current study shows that affective attitudes were more strongly related to vocational community college students' intention to engage in binge drinking than cognitive attitudes. This finding indicates that the effectiveness of interventions targeting adolescent binge drinking can be improved by incorporating content elements concerning affective attitudes

An Analysis of the Representations of the Mapping Class Group of a Multi-Geon Three-Manifold

It is well known that the inequivalent unitary irreducible representations (UIR's) of the mapping class group $G$ of a 3-manifold give rise to ``theta sectors'' in theories of quantum gravity with fixed spatial topology. In this paper, we study several families of UIR's of $G$ and attempt to understand the physical implications of the resulting quantum sectors. The mapping class group of a three-manifold which is the connected sum of $\R^3$ with a finite number of identical irreducible primes is a semi-direct product group. Following Mackey's theory of induced representations, we provide an analysis of the structure of the general finite dimensional UIR of such a group. In the picture of quantized primes as particles (topological geons), this general group-theoretic analysis enables one to draw several interesting qualitative conclusions about the geons' behavior in different quantum sectors, without requiring an explicit knowledge of the UIR's corresponding to the individual primes.Comment: 52 pages, harvmac, 2 postscript figures, epsf required. Added an appendix proving the semi-direct product structure of the MCG, corrected an error in the characterization of the slide subgroup, reworded extensively. All our analysis and conclusions remain as befor