Staying in the science stream: patterns of participation in A-level science subjects in the UK.

This paper describes patterns of participation and attainment in A-level physics, chemistry and biology from 1961 to 2009. The A-level has long been seen as an important gateway qualification for higher level study, particularly in the sciences. This long term overview examines how recruitment to these three subjects has changed in the context of numerous policies and initiatives that seek to retain more young people in the sciences. The results show that recruitment to the pure sciences has stagnated, general trends have hardly varied and the track record of government policy in influencing change is not strong. There is no evidence for increasing achievement gaps between the sexes at A-level and even national policy requiring that all young people study science up to the age of 16 appears to have had little impact on recruitment at this leve

Deterministic Dynamics and Chaos: Epistemology and Interdisciplinary Methodology

We analyze, from a theoretical viewpoint, the bidirectional interdisciplinary relation between mathematics and psychology, focused on the mathematical theory of deterministic dynamical systems, and in particular, on the theory of chaos. On one hand, there is the direct classic relation: the application of mathematics to psychology. On the other hand, we propose the converse relation which consists in the formulation of new abstract mathematical problems appearing from processes and structures under research of psychology. The bidirectional multidisciplinary relation from-to pure mathematics, largely holds with the "hard" sciences, typically physics and astronomy. But it is rather new, from the social and human sciences, towards pure mathematics

The sciences in America, circa 1880

For many years American science in the late 19th century was regarded as an intellectual backwater. This view derived from the assumption that the health of American science at the time was equivalent to the condition of pure science, especially pure physics. However, a closer look reveals that there was considerable vitality in American scientific research, especially in the earth and life sciences. This vitality is explainable in part by the natural scientific resources of the American continent but also in part by the energy given science from religious impulses, social reformism, and practicality. Furthermore, contrary to recent assumptions, the federal government was a significant patron of American science. The portrait of American science circa 1880 advanced in this article suggests that the nation's scientific enterprise was characterized by pluralism of institutional support and motive and that such pluralism has historically been the normal mode

Entanglement monotones and maximally entangled states in multipartite qubit systems

We present a method to construct entanglement measures for pure states of multipartite qubit systems. The key element of our approach is an antilinear operator that we call {\em comb} in reference to the {\em hairy-ball theorem}. For qubits (or spin 1/2) the combs are automatically invariant under SL(2,\CC). This implies that the {\em filters} obtained from the combs are entanglement monotones by construction. We give alternative formulae for the concurrence and the 3-tangle as expectation values of certain antilinear operators. As an application we discuss inequivalent types of genuine four-, five- and six-qubit entanglement.Comment: 7 pages, revtex4. Talk presented at the Workshop on "Quantum entanglement in physical and information sciences", SNS Pisa, December 14-18, 200

The effects of nanoclay on mechanical properties of high density polyethylene and polypropylene materials

Polymeric materials find usage in most places in daily life. Expected features vary depending on the use of these materials. Composite material can be formed by combining one or more different materials. Physical and chemical properties of a new produced composite material can be improved with the addition of additives and fillers to polymer materials. The addition of additives and fillers improve one or more properties at the same time, despite that, it may lead to deteriorate another property. Therefore, it is necessary to investigate the mechanical and thermal properties of these produced composite structures. This study was carried out by nanoclay addition to high density polyethylene (HDPE) and polypropylene (PP) materials. Nanoclay additions were made to the polymer matrix at mass ratios of 5% and 10%. Tensile test, tear test and the Izod impact tests were performed. It has been observed that the tensile strengths of HDPE composites decreased whereas PP composites increased with respect to the pure products. Also, the tear strengths of composites decreased compared to pure products. In the Izod impact tests, all notched specimens were broken. The values of impact strength of the PP composites were not changed in the notched Izod impact tests, whereas the HDPE composites showed a decrease. © 2018 Polish Academy of Sciences Institute of Physics. All rights reserved