Semiconductor effective charges from tight-binding theory

We calculate the transverse effective charges of zincblende compound semiconductors using Harrison's tight-binding model to describe the electronic structure. Our results, which are essentially exact within the model, are found to be in much better agreement with experiment than previous perturbation-theory estimates. Efforts to improve the results by using more sophisticated variants of the tight-binding model were actually less successful. The results underline the importance of including quantities that are sensitive to the electronic wavefunctions, such as the effective charges, in the fitting of tight-binding models.Comment: 4 pages, two-column style with 2 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#jb_t

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Asian New Religious Movements as global cultural systems

Asian New Religious Movements are attracting converts in every continent. They offer members a comprehensive cultural system of beliefs, rituals, daily routines, diet, dress styles and patterns of relationship. While often based on pre-modern Asian values and practices, these are accepted by converts from a global sweep of cultures without modification. As agents promoting the truly global application of holistic cultural systems, they warrant our attention

Physiological suitability of six West African gramineous borers (Lepidoptera: Noctuidae, Pyralidae) for development of Cotesia species complex (Hymenoptera: Braconidae)

Three gregarious, endoparasitic braconids, a Kenyan strain of Cotesia sesamiae, and the exotic Cotesia flavipes and Cotesia chilonis were imported into Benin as candidates for biological control of stem- and cob borers of maize and stemborers of millet. Host acceptability and host suitability of six gramineous borers occurring in western Africa, the noctuids Sesamia calamistis, Sesamia poephaga, Busseola fusca, the crambid Coniesta ignefusalis, and the pyralids Eldana saccharina and Mussidia nigrivenella, to these parasitoids were evaluated to test the hypothesis that new associations were superior over old association parasitoid-host relationships. All hosts were accepted by all Cotesia spp., except M. nigrivenella, which was not attacked by C. chilonis. Parasitoid progeny developed successfully in S. calamistis, S. poephaga and C. ignefusalis. S. calamistis was the most suitable host in terms of duration of developmental time, brood size and mortality of parasitoid progeny. It was concluded that because of its host specificity, the old association parasitoid C. sesamiae would have the highest chance of establishment in cereal systems in West Afric

Applications of the ACGT Master Ontology on Cancer

In this paper we present applications of the ACGT Master Ontology (MO) which is a new terminology resource for a transnational network providing data exchange in oncology, emphasizing the integration of both clinical and molecular data. The development of a new ontology was necessary due to problems with existing biomedical ontologies in oncology. The ACGT MO is a test case for the application of best practices in ontology development. This paper provides an overview of the application of the ontology within the ACGT project thus far

Amplification of a radially-polarised beam in an Yb:YAG thin slab

Amplification of an axially-symmetric, doughnut-shaped radially-polarised beam at 1030nm in a diode-bar-pumped double-pass thin Yb:YAG slab amplifier architecture without degradation in polarisation purity is demonstrated. Preliminary experiments yielded a small-signal gain of 9dB for 50W of incident pump power while maintaining the polarisation purity of the seed beam

Reviews

Review of After the Freeze: New Zealand Unions in the Economy, Keeping Employees Informed, The Future of Work, Wage Indexation - a Study of Australian Wage Issues 1975 - 1980, How Labour Markets Work, Case Studies in Adjustment, Open Cut: The Working Class in an Australian Mining Town, Industrial Accidents and Nightwork in the Manufacturing Sector, The Behavioural Sciences and Industrial Relations: Some Problems of Integratio