Promoting independent learning skills using video on digital language laboratories

This is the author's PDF version of an article published in Computer assisted language learning ©2006. The definitive version is available at http://www.informaworld.com/The article discusses the potential for developing independent learning skills using the digital language laboratory with particular reference to exploiting the increasingly available resource of digital video. It investigates the potential for recording and editing video clips from online sources and digitalising clips from analogue recordings and reflects on the current status quo regarding the complex copyright regulations in this area. It describes two pilot self-access programmes based on video clips which were undertaken with University College Chester undergraduates and reflects on the value of the experience for students in developing a wide range of language skills as well as independent learning skills using their feedback on the experience

The calibration of photographic and spectroscopic films: Reciprocity failure and thermal responses of IIaO film at liquid nitrogen temperatures

Reciprocity failure was examined for IIaO spectroscopic film. The results indicate reciprocity failure occurs at three distinct minimum points in time; 15 min, 30 min and 90 min. The results are unique because theory suggests only one minimum reciprocity failure point should occur. When incubating 70mm IIaO film for 15 and 30 min at temperatures of 30, 40, 50, and 60 C and then placing in a liquid nitrogen bath at a temperature of -190 C the film demonstrated an increase of the optical density when developed at a warm-up time of 30 min. Longer warm-up periods of 1, 2 and 3 hrs yield a decrease in optical density of the darker wedge patterns; whereas, shorter warm-up times yield an overall increase in the optical densities

Massive Electrodynamics and Magnetic Monopoles

Including torsion in the geometric framework of the Weyl-Dirac theory we build up an action integral, and obtain from it a gauge covariant (in the Weyl sense) general relativistic massive electrodynamics. Photons having an arbitrary mass, electric, and magnetic currents (Dirac's monopole) coexist within this theory. Assuming that the space-time is torsionless, taking the photons mass zero, and turning to the Einstein gauge we obtain Maxwell's electrodynamics.Comment: LaTex File, 9 pages, no figure

Even With Rehydration, Preservation in Ethanol Influences the Mechanical Properties of Bone and How Bone Responds to Experimental Manipulation

Typically, bones are harvested at the time of animal euthanasia and stored until mechanical testing. However, storage methods are not standardized, and differential effects on mechanical properties are possible between methods. The goal of this study was to investigate the effects that two common preservation methods (freezing wrapped in saline-soaked gauze and refrigerating ethanol fixed samples) have on bone mechanical properties in the context of an in vitro ribosylation treatment designed to modify mechanical integrity. It was hypothesized that there would be an interactive effect between ribose treatment and preservation method. Tibiae from twenty five 11week old female C57BL/6 mice were separated into 2 preservation groups. Micro-CT scans of contralateral pairs assessed differences in geometry prior to storage. After 7weeks of storage, bones in each pair of tibiae were soaked in a solution containing either 0M or 0.6M ribose for 1week prior to 4 point bending tests. There were no differences in any cortical geometric parameters between contralateral tibiae. There was a significant main effect of ethanol fixation on displacement to yield (-16.3%), stiffness (+24.5%), strain to yield (-13.9%), and elastic modulus (+18.5%) relative to frozen specimens. There was a significant main effect of ribose treatment for yield force (+13.9%), ultimate force (+9.2%), work to yield (+22.2%), yield stress (+14.1%), and resilience (+21.9%) relative to control-soaked bones. Postyield displacement, total displacement, postyield work, total work, total strain, and toughness were analyzed separately within each preservation method due to significant interactions. For samples stored frozen, all six properties were lower in the ribose-soaked group (49%-68%) while no significant effects of ribose were observed in ethanol fixed bones. Storage in ethanol likely caused changes to the collagen matrix which prevented or masked the embrittling effects of ribosylation that were seen in samples stored frozen wrapped in saline-soaked gauze. These data illustrate the clear importance of maintaining hydration if the eventual goal is to use bones for mechanical assessments and further show that storage in ethanol can alter potential to detect effects of experimental manipulation (in this case ribosylation)

Struggling for food in a time of crisis: A comment on Caplan in this issue

This commentary sets Caplan’s arguments about food banks and food poverty in the broader context of changes to the welfare state, the ‘charitization’ of state welfare and the need to address food poverty within a framework of dignity rather than charity

The free surface of superfluid 4He at zero temperature

The structure and energetics of the free surface of superfluid $^4$He are studied using the diffusion Monte Carlo method. Extending a previous calculation by Vall\'es and Schmidt, which used the Green's function Monte Carlo method, we study the surface of liquid $^4$He within a slab geometry using a larger number of particles in the slab and an updated interatomic potential. The surface tension is accurately estimated from the energy of slabs of increasing surface density and its value is close to one of the two existing experimental values. Results for the density profiles allow for the calculation of the surface width which shows an overall agreement with recent experimental data. The dependence on the transverse direction to the surface of other properties such as the two-body radial distribution function, structure factor, and one-body density matrix is also studied. The condensate fraction, extracted from the asymptotic behavior of the one-body density matrix, shows an unambiguous enhancement when approaching the surface.Comment: RevTex, 11 pages, accepted in Phys. Rev.

Health Impacts Model

This report presents the draft outline of the CORFU Health Impacts Model. The model consists of assessing the risk to human health in four steps: Hazard identification Hazard characterisation (or dose-response assessment) Exposure assessment Risk characterisation The health impacts model has four components. The first of these is the risk to human life component, and adapts a model developed in the FLOODsite project to estimate the number of deaths and injuries that could be caused by flooding. The next component relates to waterborne diseases and illnesses that can be assessed by means of a Quantitative Microbial Risk Assessment. Thirdly, the model takes account of other diseases (such as those transmitted by vectors) and suggests the use of relative risk information to estimate the impact of this disease. A similar approach is suggested to consider the mental health impacts of flooding. Finally, the report describes how the health risks could be characterised using the Disability Adjusted Life Year (DALY).The work described in this publication was supported by the European Community’s Seventh Framework Programme through the grant to the budget of CORFU Collaborative Research on Flood Resilience in Urban Areas, Contract 244047

Rasch Analysis, Dimensionality, and Scoring of the Neuropsychiatric Inventory Irritability and Aggression Subscales in Individuals With Traumatic Brain Injury

Objectives To develop, for versions completed by individuals with traumatic brain injury (TBI) and an observer, a more precise metric for the Neuropsychiatric Inventory (NPI) Irritability and Aggression subscales using all behavioral item ratings for use with individuals with TBI and to address the dimensionality of the represented behavioral domains. Design Rasch and confirmatory factor analyses of retrospective baseline NPI data from 3 treatment studies. Setting Postacute rehabilitation clinic. Participants NPI records (N = 525) consisting of observer ratings (n = 287) and self-ratings (n = 238) by participants with complicated mild, moderate, or severe TBI at least 6 months postinjury. Interventions Not applicable. Main Outcome Measures Frequency and severity ratings from NPI Irritability/Lability and Agitation/Aggression subscales. Results Confirmatory factor analyses of both observer and participant ratings showed good fit for either a 1-factor or a 2-factor solution. Consistent with this, the Rasch model also fit the data well with aggression items indicating the more severe end of the construct and irritability items populating the milder end. Conclusions Irritability and aggression appear to represent different levels of severity of a single construct. The derived Rasch metric offers a measure of this construct based on responses to all specific items that is appropriate for parametric statistical analysis and may be useful in research and clinical assessments of individuals with TBI

Discrete Laplace Cycles of Period Four

We study discrete conjugate nets whose Laplace sequence is of period four. Corresponding points of opposite nets in this cyclic sequence have equal osculating planes in different net directions, that is, they correspond in an asymptotic transformation. We show that this implies that the connecting lines of corresponding points form a discrete W-congruence. We derive some properties of discrete Laplace cycles of period four and describe two explicit methods for their construction

The Path Integral Monte Carlo Calculation of Electronic Forces

We describe a method to evaluate electronic forces by Path Integral Monte Carlo (PIMC). Electronic correlations, as well as thermal effects, are included naturally in this method. For fermions, a restricted approach is used to avoid the ``sign'' problem. The PIMC force estimator is local and has a finite variance. We applied this method to determine the bond length of H$_2$ and the chemical reaction barrier of H+H$_2\longrightarrow$H$_2$+H. At low temperature, good agreement is obtained with ground state calculations. We studied the proton-proton interaction in an electron gas as a simple model for hydrogen impurities in metals. We calculated the force between the two protons at two electronic densities corresponding to Na ($r_s=3.93$) and Al ($r_s=2.07$) using a supercell with 38 electrons. The result is compared to previous calculations. We also studied the effect of temperature on the proton-proton interaction. At very high temperature, our result agrees with the Debye screening of electrons. As temperature decreases, the Debye theory fails both because of the strong degeneracy of electrons and most importantly, the formation of electronic bound states around the protons.Comment: 18 pages, 10 figure