Novel Circuit Fabrication Techniques for Reduced Environmental Impact

This paper proposes a novel technique for low cost circuit manufacture which it is hoped will offer significant reduction in environmental impact, both in terms of production process, and end of life. The technique is to use a pattern printed on paper by conventional offset lithographic techniques to form interconnection circuitry. Initial research is concentrating on the selection of appropriate conductive inks, and substrate materials. At present, components are attached using conductive adhesives, but the feasibility of placing components during the final printing pass, and using a form of conductive ink to provide the bond, is investigated

Isolating LCDs at end-of-life using active disassembly technology: A feasibility study

The European Union draft Waste Electrical and Electronic Equipment (WEEE) directive calls for the removal and separate treatment of liquid crystal displays (LCD). This aspect of the legislation will potentially have an important impact upon the future `End of Life' (EoL) processing of much WEEE. Active Disassembly using Smart Materials (ADSM) has been proven to have applicability in self-dismantling, nondestructive and rapid disassembly of small electronic products. This paper investigates the technical feasibility of removing LCD screens from IT communication products using ASDM technology. In this paper an option is suggested to cleanly separate LCD screens from printed circuit boards, utilizing an LCD bracket made from `shape memory polymer'. The case study products employed are Nokia Japanese J-Phones. Demonstration experiments with initial results are presented, and future developments discussed. SMB glass transformation temperatures (Tg) and time efficiency in disassembly are considered

Radiocarbon dating of methane and carbon dioxide evaded from a temperate peatland stream

Streams draining peatlands export large quantities of carbon in different chemical forms and are an important part of the carbon cycle. Radiocarbon (14C) analysis/dating provides unique information on the source and rate that carbon is cycled through ecosystems, as has recently been demonstrated at the air-water interface through analysis of carbon dioxide (CO2) lost from peatland streams by evasion (degassing). Peatland streams also have the potential to release large amounts of methane (CH4) and, though 14C analysis of CH4 emitted by ebullition (bubbling) has been previously reported, diffusive emissions have not. We describe methods that enable the 14C analysis of CH4 evaded from peatland streams. Using these methods, we investigated the 14C age and stable carbon isotope composition of both CH4 and CO2 evaded from a small peatland stream draining a temperate raised mire. Methane was aged between 1617-1987 years BP, and was much older than CO2 which had an age range of 303-521 years BP. Isotope mass balance modelling of the results indicated that the CO2 and CH4 evaded from the stream were derived from different source areas, with most evaded CO2 originating from younger layers located nearer the peat surface compared to CH4. The study demonstrates the insight that can be gained into peatland carbon cycling from a methodological development which enables dual isotope (14C and 13C) analysis of both CH4 and CO2 collected at the same time and in the same way

Monoamine oxidase-A modulates apoptotic cell death induced by staurosporine in human neuroblastoma cells

Monoamine oxidases (MAOs) are mitochondrial enzymes which control the levels of neurotransmitters in the brain and dietary amines in peripheral tissues via oxidative deamination. MAO has also been implicated in cell signalling. In this study, we describe the MAO-A isoform as functional in apoptosis induced by staurosporine (STS) in human dopaminergic neuroblastoma cells (SH-SY5Y). Increased levels of MAO-A activity were induced by STS, accompanied by increased MAO-A protein and activation of the initiator of the intrinsic pathway, caspase 9, and the executioner caspase 3. MAO-A mRNA levels were unaffected by STS, suggesting that changes in MAO-A protein are due to post-transcriptional events. Two unrelated MAO-A inhibitors reduced caspase activation. STS treatment resulted in sustained activation of the mitogen-activated protein kinase pathway enzymes extracellular regulated kinase, c-jun terminal kinase and p38, and depletion of the anti-apoptotic protein Bcl-2. These changes were significantly reversed by MAO inhibition. Production of reactive oxygen species was increased following STS exposure, which was blocked by both MAO inhibition and the antioxidant N-acetylcysteine. Therefore our data provide evidence that MAO-A, through its production of reactive oxygen species as a by-product of its catalytic activity on the mitochondrial surface, is recruited by the cell to enhance apoptotic signalling

In-service Initial Teacher Education in the Learning and Skills Sector in England: Integrating Course and Workplace Learning

The aim of the paper is to advance understanding of in-service learning and skills sector trainee teachers’ learning and propose ways of improving their learning. A conceptual framework is developed by extending Billett’s (International Journal of Educational Research 47:232–240, 2008) conceptualisation of workplace learning, as a relationally interdependent process between the opportunities workplaces afford for activities and interactions and how individuals engage with these, to a third base of participation, the affordances of the initial teacher education course. Hager and Hodkinson’s (British Educational Research Journal 35:619–638, 2009) metaphor of ‘learning as becoming’ is used to conceptualise the ways trainees reconstruct learning in a continuous transactional process of boundary crossing between course and workplace. The findings of six longitudinal case studies of trainees’ development, and evidence from other studies, illustrate the complex interrelationships between LSS workplace affordances, course affordances and trainee characteristics and the ways in which trainees reconstruct learning in each setting. The experience of teaching and interacting with learners, interactions with colleagues, and access to workplace resources and training are important workplace affordances for learning. However, some trainees have limited access to these affordances. Teaching observations, course activities and experiences as a learner are significant course affordances. Trainees’ beliefs, prior experiences and dispositions vary and significantly influence their engagement with course and workplace affordances. It is proposed that better integration of course and workplace learning through guided participation in an intentional workplace curriculum and attention to the ways trainees choose to engage with this, together with the use of practical theorising has the potential to improve trainee learning

A Class of upwind methods for Conservation Laws

Various new methods for the solution of hyperbolic systems of conservation laws in one, two and three space dimensions are developed. All are explicit, conservative timemarching methods that are second order accurate in space and time in regions of smooth flow and make use of local Riemann problems at intercell boundaries. In one space dimension, the Weighted Average Flux (w af ) approach of Toro is extended to generate a scheme that is stable with timesteps twice as large as those allowed by the stability conditions of the original scheme. A Riemann problem based extension of the Warming-Beam scheme is considered. Total Variation Diminishing (t v d ) conditions are enforced for both schemes. Numerical results for the Euler Equations of Gas Dynamics are presented. In two and three space dimensions, finite volume versions of the waf scheme on Cartesian grids are derived for the linear advection equation. Two two dimensional schemes are found that are second order accurate in space and time. One of these is extended for the solution of nonlinear systems of hyperbolic conservation laws in two separate ways. The resulting schemes are tested on the Shallow Water equations. The equivalent three dimensional schemes are also discussed. The two dimensional schemes are then extended for use on structured, body-fitted grids of quadrilaterals and one of these extensions is used to demonstrate the phenomena of Mach reflection of shallow water bores.Ph

Design of Virtual Tutoring Agents for a Virtual Biology Experiment

Virtual learning environments (VLEs) may possess many advantages over traditional teaching methods in skills training that offer empowerment of constructing the skills by freely exploring a VLE. However, a conflict between the free exploration and ensuring the learning tasks tackled emerges in the learning process. A strategy to balance the conflict is to employ virtual tutoring agents to scaffold the learning tasks. This research has been carried out to investigate the issues of design and utility of a virtual tutoring agent system in a VLE to allow higher education (university based) students to practise immunology laboratory experiments, which simulates a well known immunochemical assay in the Life Sciences area, namely a Radio Immunoassay. This paper discusses the classification of category of the virtual agents in a VLE and focuses on the design of tutoring agents. Three types of the tutoring agents have been selected and implemented in the Radio Immunoassay simulation. The considered points in programming the virtual tutoring agents and their tasks are presented in this paper. A formative evaluation studies have been carried out and discussed to verify the designed virtual tutoring agents are satisfied to the target students' needs. Keywords Design of virtual tutoring agent, agent-based virtual learning environments, agent-based virtual environment for biology experiment, agent-based training software in biology, intelligent virtual laboratory, interactive learning software

Modeling Non-Force-Free and Deformed Flux Ropes in Titan’s Ionosphere

Previous work at Titan presented a set of 85 flux ropes detected during Cassini flybys of Titan from 2005 to 2017. In that study a force‐free model was used to determine the radii and axial magnetic field of the flux ropes. In this work we apply non‐force‐free models. The non‐force‐free model shows an improvement in the number of flux ropes that can be fitted with a model, along with improved uncertainties and χ2 values. A number of asymmetries and features in the magnetometer data cannot be reproduced by either model; therefore, we deform the force‐free model to show that small deformations can replicate these features. One such deformation is to use an elliptical cross section, which replicates a plateau in magnetic field strength along with asymmetries on either side of the center of the flux ropes. Additionally, we explore the properties of bending a flux rope, where we find that minimum variance analysis becomes increasingly degenerate with bending, along with a slight bend causing the switching of the axial field direction from intermediate to maximum variance direction. We conclude that the flux ropes at Titan show aspects of developing flux ropes, compared to other planetary bodies, which exhibit more agreement to the force‐free assumptions of mature flux ropes