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The tradition which has assumed since the past century the central role of practical work in science education, is argued in this paper. The author reviews the assumptions that justify the educational benefits of practical work, and he does a critical scrutiny of its use and misuse in science education

Changing French Orientalism

Cataloged from PDF version of article.The article focuses on the story of the opera "Tarare," which became prevalent throughout Europe from 1760 to 1780. She examines the story of the opera, which centers the life of a Christian noblewoman who was abducted by an oriental potentate and must be rescued by her lover. However, the author points out that opera illustrate the complex discursive genealogy of French political, social, and philosophical concerns in the final quarter of the 18th century

Role of Insects and Diseases in a Jack Pine Provenance Study

Two jack pine plantations were established at the Cloquet Forestry Center, Cloquet, Minnesota, in 1942 and 1943, using trees originating from 22 sites in the United States and 10 in Canada. From 1945 to 1953 the incidence of attack by insects and diseases was recorded individually for all trees, and in 1980-1981 the diameter and form of both living and dead trees were recorded. There were differences in the incidence of attack by the pests and in tree response to early injury among the various seed sources. In 1980 and in 1981 there were differences in tree form resulting from insect and both living and dead pest-free trees had the best form. The diameter increases from 1955 to 1980-1981 were almost identical for all categories with the exception of the dead pest-free trees which had the smallest diameters

Triple mode Cepheid masses

Unconventional composition structures are proposed to explain the periods of the triple mode Cepheid aC And. A strong Cepheid wind appears to enrich helium in the convection zones down to about 60,000 K or 70,000 K. Then some downward partial mixing occurs to the bottom of a layer with about 1-q = .0005 of the stellar mass. It was found that AC And was not unlike anomalous Cepheids. However, masses of betwen one and two solar masses are suggested and the population is more likely a type two

A Low Cost Remote Sensing System Using PC and Stereo Equipment

A system using a personal computer, speaker, and a microphone is used to detect objects, and make crude measurements using a carrier modulated by a pseudorandom noise (PN) code. This system can be constructed using a personal computer and audio equipment commonly found in the laboratory or at home, or more sophisticated equipment that can be purchased at reasonable cost. We demonstrate its value as an instructional tool for teaching concepts of remote sensing and digital signal processing.Comment: Accepted for publication in American Journal of Physic

Modeling Quantum Optical Components, Pulses and Fiber Channels Using OMNeT++

Quantum Key Distribution (QKD) is an innovative technology which exploits the laws of quantum mechanics to generate and distribute unconditionally secure cryptographic keys. While QKD offers the promise of unconditionally secure key distribution, real world systems are built from non-ideal components which necessitates the need to model and understand the impact these non-idealities have on system performance and security. OMNeT++ has been used as a basis to develop a simulation framework to support this endeavor. This framework, referred to as "qkdX" extends OMNeT++'s module and message abstractions to efficiently model optical components, optical pulses, operating protocols and processes. This paper presents the design of this framework including how OMNeT++'s abstractions have been utilized to model quantum optical components, optical pulses, fiber and free space channels. Furthermore, from our toolbox of created components, we present various notional and real QKD systems, which have been studied and analyzed.Comment: Published in: A. F\"orster, C. Minkenberg, G. R. Herrera, M. Kirsche (Eds.), Proc. of the 2nd OMNeT++ Community Summit, IBM Research - Zurich, Switzerland, September 3-4, 201

The New Intergovernmentalism: European Integration in the Post-Maastricht Era

The post-Maastricht period is marked by an integration paradox. While the basic constitutional features of the European Union have remained stable, EU activity has expanded to an unprecedented degree. This form of integration without supranationalism is no exception or temporary deviation from traditional forms of European integration. Rather, it is a distinct phase of European integration, what is called ‘the new intergovernmentalism’ in this article. This approach to post-Maastricht integration challenges theories that associate integration with transfers of competences from national capitals to supranational institutions and those that reduce integration to traditional socioeconomic or security-driven interests. This article explains the integration paradox in terms of transformations in Europe's political economy, changes in preference formation and the decline of the ‘permissive consensus’. It presents a set of six hypotheses that develop further the main claims of the new intergovernmentalism and that can be used as a basis for future research.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1111/jcms.1221

More from the horse's mouth: What scientists say about science as a social practice

This research study sought to identify prominent features of the nature of science (NOS) embedded in authentic scientific inquiry. Fourteen well-established scientists from different parts of the world, working in experimental or theoretical research, in both traditional fields such as astrophysics and rapidly growing research fields such as molecular biology, participated as the informants of the study. The descriptions of their practices revealed eight prominent categories of NOS features. In an earlier paper of ours, we have reported four categories under the two themes: (1) the methods of scientific investigation and (2) the role and status of scientific knowledge. In this paper, we focus on the remaining four categories under the theme: social dimensions of science. Scientists' descriptions of their practices have 'put some flesh on the bones' of the assertion that science is socially and culturally embedded. These descriptions also have considerable potential for development into interesting case studies as teaching resources to enhance and enrich students' understanding of NOS. © 2010 Taylor & Francis.postprin

Weathering microenvironments on feldspar surfaces: implications for understanding fluid-mineral reactions in soils

The mechanisms by which coatings develop on weathered grain surfaces, and their potential impact on rates of fluid-mineral interaction, have been investigated by examining feldspars from a 1.1 ky old soil in the Glen Feshie chronosequence, Scottish highlands. Using the focused ion beam technique, electron-transparent foils for characterization by transmission electron microscopy were cut from selected parts of grain surfaces. Some parts were bare whereas others had accumulations, a few micrometres thick, of weathering products, often mixed with mineral and microbial debris. Feldspar exposed at bare grain surfaces is crystalline throughout and so there is no evidence for the presence of the amorphous 'leached layers' that typically form in acid-dissolution experiments and have been described from some natural weathering contexts. The weathering products comprise sub-μm thick crystallites of an Fe-K aluminosilicate, probably smectite, that have grown within an amorphous and probably organic-rich matrix. There is also evidence for crystallization of clays having been mediated by fungal hyphae. Coatings formed within Glen Feshie soils after ∼1.1 ky are insufficiently continuous or impermeable to slow rates of fluid-feldspar reactions, but provide valuable insights into the complex weathering microenvironments on debris and microbe-covered mineral surfaces

Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to Microlophium carnosum and Drepanosiphum platanoidis Schrank

This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. Concentrations of Zn in two aphid species are dependant on species and exposure