Risk reduction: Recontexualizing health as a physical education curriculum

While there is sufficient evidence to suggest that physical activity is inversely related to lifestyle diseases, researchers are far from being certain that this evidence extends to children. Nevertheless, the school physical education curriculum has been targeted as an institutional agency that could have a significant impact on health during childhood and later during adulthood if individuals could be habituated to assume a physically active lifestyle. The purpose of this article is to examine the recontextualization of biomedical knowledge into an ideology of healthism in which health is conceived as a controllable certainty and used as a pedagogical construction to transform school physical education. Using a Foucauldian perspective, we explore how the atomized biomedical model of chemical and physical relationships is constructed, reproduced, and perpetuated to service and empower the discourse and the practices of researchers and scholars. In this process the sociological or cultural aspects of public health are marginalized or ignored. As a result of this examination, alternative approaches are proposed that engage the limitations of the biomedical model and openly consider the insights that are available from the social sciences regarding what participation in physical activity means to individuals.

Blur adaptation explained by a norm-based model of contrast adaptation

Adapting to blurred images makes in-focus images look too sharp, and vice-versa (Webster et al, 2002 Nature Neuroscience 5 839 - 840). We asked how such blur adaptation is related to contrast adaptation. Georgeson (1985 Spatial Vision 1 103 - 112) found that grating contrast adaptation followed a subtractive rule: perceived (matched) contrast of a grating was fairly well predicted by subtracting some fraction k(~0.3) of the adapting contrast from the test contrast. Here we apply that rule to the responses of a set of spatial filters at different scales and orientations. Blur is encoded by the pattern of filter response magnitudes over scale. We tested two versions - the 'norm model' and 'fatigue model' - against blur-matching data obtained after adaptation to sharpened, in-focus or blurred images. In the fatigue model, filter responses are simply reduced by exposure to the adapter. In the norm model, (a) the visual system is pre-adapted to a focused world and (b) discrepancy between observed and expected responses to the experimental adapter leads to additional reduction (or enhancement) of filter responses during experimental adaptation. The two models are closely related, but only the norm model gave a satisfactory account of results across the four experiments analysed, with one free parameter k. This model implies that the visual system is pre-adapted to focused images, that adapting to in-focus or blank images produces no change in adaptation, and that adapting to sharpened or blurred images changes the state of adaptation, leading to changes in perceived blur or sharpness.

Bio-inspired carbon electro-catalysis for the oxygen reduction reaction

We report the synthesis, characterisation and catalytic performance of two nature-inspired biomass-derived electro-catalysts for the oxygen reduction reaction in fuel cells. The catalysts were prepared via pyrolysis of a real food waste (lobster shells) or by mimicking the composition of lobster shells using chitin and CaCO3 particles followed by acid washing. The simplified model of artificial lobster was prepared for better reproducibility. The calcium carbonate in both samples acts as a pore agent, creating increased surface area and pore volume, though considerably higher in artificial lobster samples due to the better homogeneity of the components. Various characterisation techniques revealed the presence of a considerable amount of hydroxyapatite left in the real lobster samples after acid washing and a low content of carbon (23%), nitrogen and sulphur (<1%), limiting the surface area to 23 m2/g, and consequently resulting in rather poor catalytic activity. However, artificial lobster samples, with a surface area of ≈200 m2/g and a nitrogen doping of 2%, showed a promising onset potential, very similar to a commercially available platinum catalyst, with better methanol tolerance, though with lower stability in long time testing over 10,000 s.

Interaction of quinolone antibiotics with the human intestinal CACO-2 cell model

The transport of a group of quinolone antibiotics across the human intestinal model, Caco-2 cells, was investigated. It was found that the transport of the quinolones generally correlated with the lipophilicity of the compounds, indicating the passive diffusional transcellular processes were involved. However, it was observed that the transport in both directions apical-to-basolateral and basolateral-to-apical was not equivalent, and polarised transport occurred. For all the quinolones studied except, BMS-284756-01, it was found that the basolateral-to-apical transport was significantly greater than the apical-to-basolateral transport. This finding suggested that the quinolones underwent a process of active secretion. The pKas and logPs for the quinolones were determined using potentiometric titrations. The measured logP values were compared with those determined using theoretical methods. The theoretical methods for calculating logP including the Moriguchi method correlated poorly with the measured logP values. Further investigations revealed that there may be an active transporter involved in the apical-to-basolateral transport of quinolones as well. This mechanism was sensitive to competing quinolones, but, it was unaffected by the metabolic inhibitor combination of sodium azide (15mM) with 2-deoxy-D-glucose (50mM). The basolateral-to-apical transport of quinolones was found to be sensitive to inhibition by a number of different inhibitors. The metabolic inhibitors, sodium azide (15mM) with 2-deoxy-D-glucose (50mM) and 2,4-dinitrophenol (1mM), were able to reduce the basolateral-to-apical transport of quinolones. A reduction in temperature from 37°C to 2°C caused an 80-fold decrease in the transport of gatifloxacin in both directions, however, this effect was not sufficient to abolish the greater basolateral-to-apical secretion. As with apical-to-basolateral transport, it was found that quinolones competed with gatifloxacin for basolateral-to-apical transport, both ofloxacin (100μM) and norfloxacin (100μM) significantly (P<0.003) decreased the basolateral-to-apical transport of gatifloxacin; however, ciprofloxacin (100μM and 300μM) had no effect. A number of inhibitors of various transport systems were also investigated. It was found that the anion transport inhibitor, probenecid (100 μM) had a significant inhibitory effect on the basolateral-to-apical transport of ciprofloxacin (P=0.039), while the cation transport inhibitor cimetidine (100μM and 500μM) had no effect. The organic anion exchange inhibitor 4,4'diisothiocyanostilbene-2-2' -disulphonic acid DIDS (400μM) also had a significant inhibitory effect (P=O.O 13). The PgP inhibitor and anion exchange inhibitor verapamil (400Mμ) was able to completely abolish the basolateral-to-apical secretion of gatifloxacin and bring it into line with the apical-to-basolateral flux. In conclusion, the apical-to-basolateral and basolateral-toapical transport of quinolones involved an active component. The basolateral-to-apical secretion was abolished by a verapamil (400μM), a bisubstrate for PgP and the anion transporter.

Lead time reduction for new products

The research, which was given the terms of reference, "To cut the lead time for getting new products into volume production", was sponsored by a company which develops and manufactures telecommunications equipment. The research described was based on studies made of the development of two processors which were designed to control telephone exchanges in the public network. It was shown that for each of these products, which were large electronic systems containing both hardware and software, most of their lead time was taken up with development. About half of this time was consumed by activities associated with redesign resulting from changes found to be necessary after the original design had been built. Analysing the causes of design changes showed the most significant to be Design Faults. The reasons why these predominated were investigated by seeking the collective opinion from design staff and their management using a questionnaire. Using the results from these studies to build upon the works of other authors, a model of the development process of large hierarchical systems is derived. An important feature of this model is its representation of iterative loops due to design changes. In order to reduce the development time, two closely related philosophies are proposed: By spending more time at the early stages of development (detecting and remedying faults in the design) even greater savings can be made later on, The collective performance of the development organisation would be improved by increasing the amount and speed of feedback about that performance. A trial was performed to test these philosophies using readily available techniques for design verification. It showed that about an 11 per cent saving would be made on the development time and that the philosophies might be equally successfully applied to other products and techniques.

Discriminative training of the hidden vector state model for semantic parsing

In this paper, we discuss how discriminative training can be applied to the hidden vector state (HVS) model in different task domains. The HVS model is a discrete hidden Markov model (HMM) in which each HMM state represents the state of a push-down automaton with a finite stack size. In previous applications, maximum-likelihood estimation (MLE) is used to derive the parameters of the HVS model. However, MLE makes a number of assumptions and unfortunately some of these assumptions do not hold. Discriminative training, without making such assumptions, can improve the performance of the HVS model by discriminating the correct hypothesis from the competing hypotheses. Experiments have been conducted in two domains: the travel domain for the semantic parsing task using the DARPA Communicator data and the Air Travel Information Services (ATIS) data and the bioinformatics domain for the information extraction task using the GENIA corpus. The results demonstrate modest improvements of the performance of the HVS model using discriminative training. In the travel domain, discriminative training of the HVS model gives a relative error reduction rate of 31 percent in F-measure when compared with MLE on the DARPA Communicator data and 9 percent on the ATIS data. In the bioinformatics domain, a relative error reduction rate of 4 percent in F-measure is achieved on the GENIA corpus.

Optimal input/output reduction in production processes

While conventional Data Envelopment Analysis (DEA) models set targets for each operational unit, this paper considers the problem of input/output reduction in a centralized decision making environment. The purpose of this paper is to develop an approach to input/output reduction problem that typically occurs in organizations with a centralized decision-making environment. This paper shows that DEA can make an important contribution to this problem and discusses how DEA-based model can be used to determine an optimal input/output reduction plan. An application in banking sector with limitation in IT investment shows the usefulness of the proposed method.

Representing the assessment process for psychodynamic psychotherapy within a computerized model of human classification

This research describes a computerized model of human classification which has been constructed to represent the process by which assessments are made for psychodynamic psychotherapy. The model assigns membership grades (MGs) to clients so that the most suitable ones have high values in the therapy category. Categories consist of a hierarchy of components, one of which, ego strength, is analysed in detail to demonstrate the way it has captured the psychotherapist's knowledge. The bottom of the hierarchy represents the measurable factors being assessed during an interview. A questionnaire was created to gather the identified information and was completed by the psychotherapist after each assessment. The results were fed into the computerized model, demonstrating a high correlation between the model MGs and the suitability ratings of the psychotherapist (r = .825 for 24 clients). The model has successfully identified the relevant data involved in assessment and simulated the decision-making process of the expert. Its cognitive validity enables decisions to be explained, which means that it has potential for therapist training and also for enhancing the referral process, with benefits in cost effectiveness as well as in the reduction of trauma to clients. An adapted version measuring client improvement would give quantitative evidence for the benefit of therapy, thereby supporting auditing and accountability. © 1997 The British Psychological Society.

Granular superconductors:from the nonlinear σ model to the Bose-Hubbard description

We modify a nonlinear σ model (NLσM) for the description of a granular disordered system in the presence of both the Coulomb repulsion and the Cooper pairing. We show that under certain controlled approximations the action of this model is reduced to the Ambegaokar-Eckern-Schön (AES) action, which is further reduced to the Bose-Hubbard (or “dirty-boson”) model with renormalized coupling constants. We obtain an effective action which is more general than the AES one but still simpler than the full NLσM action. This action can be applied in the region of parameters where the reduction to the AES or the Bose-Hubbard model is not justified. This action may lead to a different picture of the superconductor-insulator transition in two-dimensional systems.

Mathematical Model and Simulation of a Pneumatic Apparatus for In-Drilling Alignment of an Inertial Navigation Unit during Horizontal Well Drilling

Conventional methods in horizontal drilling processes incorporate magnetic surveying techniques for determining the position and orientation of the bottom-hole assembly (BHA). Such means result in an increased weight of the drilling assembly, higher cost due to the use of non-magnetic collars necessary for the shielding of the magnetometers, and significant errors in the position of the drilling bit. A fiber-optic gyroscope (FOG) based inertial navigation system (INS) has been proposed as an alternative to magnetometer -based downhole surveying. The utilizing of a tactical-grade FOG based surveying system in the harsh downhole environment has been shown to be theoretically feasible, yielding a significant BHA position error reduction (less than 100m over a 2-h experiment). To limit the growing errors of the INS, an in-drilling alignment (IDA) method for the INS has been proposed. This article aims at describing a simple, pneumatics-based design of the IDA apparatus and its implementation downhole. A mathematical model of the setup is developed and tested with Bloodshed Dev-C++. The simulations demonstrate a simple, low cost and feasible IDA apparatus.

Dimension Reduction of the Explanatory Variables in Multiple Linear Regression

2002 Mathematics Subject Classification: 62J05, 62G35.

Psychotherapy and social change:utilizing principles of cognitive-behavioral therapy to help develop new prejudice-reduction interventions

We propose that key concepts from clinical psychotherapy can inform science-based initiatives aimed at building tolerance and community cohesion. Commonalities in social and clinical psychology are identified regarding (1) distorted thinking (intergroup bias and cognitive bias), (2) stress and coping (at intergroup level and intrapersonal level), and (3) anxiety (intergroup anxiety and pathological anxiety). On this basis we introduce a new cognitive-behavioral model of social change. Mental imagery is the conceptual point of synthesis, and anxiety is at the core, through which new treatment-based approaches to reducing prejudice can be developed. More generally, we argue that this integration is illustrative of broader potential for cross-disciplinary integration in the social and clinical sciences, and has the potential to open up new possibilities and opportunities for both disciplines.

A low mortality, high morbidity Reduced Intensity Status Epilepticus (RISE) model of epilepsy and epileptogenesis in the rat

Animal models of acquired epilepsies aim to provide researchers with tools for use in understanding the processes underlying the acquisition, development and establishment of the disorder. Typically, following a systemic or local insult, vulnerable brain regions undergo a process leading to the development, over time, of spontaneous recurrent seizures. Many such models make use of a period of intense seizure activity or status epilepticus, and this may be associated with high mortality and/or global damage to large areas of the brain. These undesirable elements have driven improvements in the design of chronic epilepsy models, for example the lithium-pilocarpine epileptogenesis model. Here, we present an optimised model of chronic epilepsy that reduces mortality to 1% whilst retaining features of high epileptogenicity and development of spontaneous seizures. Using local field potential recordings from hippocampus in vitro as a probe, we show that the model does not result in significant loss of neuronal network function in area CA3 and, instead, subtle alterations in network dynamics appear during a process of epileptogenesis, which eventually leads to a chronic seizure state. The model’s features of very low mortality and high morbidity in the absence of global neuronal damage offer the chance to explore the processes underlying epileptogenesis in detail, in a population of animals not defined by their resistance to seizures, whilst acknowledging and being driven by the 3Rs (Replacement, Refinement and Reduction of animal use in scientific procedures) principles.

Perception of global image contrast is predicted by the same spatial integration model of gain control as detection and discrimination

How are the image statistics of global image contrast computed? We answered this by using a contrast-matching task for checkerboard configurations of ‘battenberg’ micro-patterns where the contrasts and spatial spreads of interdigitated pairs of micro-patterns were adjusted independently. Test stimuli were 20 × 20 arrays with various sized cluster widths, matched to standard patterns of uniform contrast. When one of the test patterns contained a pattern with much higher contrast than the other, that determined global pattern contrast, as in a max() operation. Crucially, however, the full matching functions had a curious intermediate region where low contrast additions for one pattern to intermediate contrasts of the other caused a paradoxical reduction in perceived global contrast. None of the following models predicted this: RMS, energy, linear sum, max, Legge and Foley. However, a gain control model incorporating wide-field integration and suppression of nonlinear contrast responses predicted the results with no free parameters. This model was derived from experiments on summation of contrast at threshold, and masking and summation effects in dipper functions. Those experiments were also inconsistent with the failed models above. Thus, we conclude that our contrast gain control model (Meese & Summers, 2007) describes a fundamental operation in human contrast vision.

Semi-supervised Gaussian process latent variable model with pairwise constraints

In machine learning, Gaussian process latent variable model (GP-LVM) has been extensively applied in the field of unsupervised dimensionality reduction. When some supervised information, e.g., pairwise constraints or labels of the data, is available, the traditional GP-LVM cannot directly utilize such supervised information to improve the performance of dimensionality reduction. In this case, it is necessary to modify the traditional GP-LVM to make it capable of handing the supervised or semi-supervised learning tasks. For this purpose, we propose a new semi-supervised GP-LVM framework under the pairwise constraints. Through transferring the pairwise constraints in the observed space to the latent space, the constrained priori information on the latent variables can be obtained. Under this constrained priori, the latent variables are optimized by the maximum a posteriori (MAP) algorithm. The effectiveness of the proposed algorithm is demonstrated with experiments on a variety of data sets. © 2010 Elsevier B.V.