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LEGO storytelling:an initial observational study to enable children to become partners in their own assessment
No full textThis paper will explore the validity of an approach to assessment by reporting initial findings from pre study work with young children who have been observed playing with LEGO in a nursery setting. It will demonstrate how these interactions have informed our views on children as potential participants in their own assessment using traditional construction toys and the ways new technology could be used to truly listen and assess knowledge through the valuable medium of storytelling. Initial observations highlighted the following interesting aspects: (i) In the classroom, many of the “live” conversations that took place between the practitioner and the child were relatively shallow, rushed and interrupted. (ii) Video recordings of children enacting stories do not serve as the basis of a learning conversation as the children don't remember the story and are distracted by their own presence in the video. (iii) The children built stories with ready made objects and elemental objects rather than the more abstract bricks.Keywords: Innovation, technology, research projects, assessment, storytelling LEGO, young children, Scottish Curriculum. <br/
Peak cardiac power output, measured noninvasively, is a powerful predictor of outcome in chronic heart failure
No full textBackground-The cardiac output (CO) response to exercise and other invasively derived hemodynamic variables has beeh variably described to provide better prognostication than peak Vo(2) in patients with chronic heart failure. Using noninvasive measurements of CO during exercise, we compared the prognostic value of peak CO and cardiac power to peak Vo(2) in chronic heart failure patients.Method and Results-One hundred seventy-one consecutive patients with chronic heart failure underwent symptom limited bicycle exercise with noninvasive estimation Of CO using an inert gas rebreathing method. An accurate measure of peak CO was obtained in 148 patients (85% of patients; mean age, 53 +/- 14 years; 80% male; left ventricular ejection fraction, 24 +/- 12%; ischemic etiology, 34%). Peak cardiac power was derived from the product of the peak mean arterial blood pressure and CO divided by 451. End points consisted of death, urgent heart transplant, or left ventricular assist device implantation. Duration of follow-up averaged 337 +/- 252 days (median, 295 days). Univariate and multivariate analysis were performed. The variables analyzed included peak Vo(2) peak CO, peak cardiac power, VE/VCO2 slope, and Vo(2) at anaerobic threshold. Event-free survival for the entire cohort was 83% with 5 deaths, 4 left ventricular assist device implants, and 16 urgent transplants. Peak Vo(2) was 12.9 +/- 4.5 mL/kg per min, and peak cardiac power was 1.7 +/- 0.9 W. Peak Vo(2), peak CO, peak cardiac power, VE/VCO2 slope, and Vo(2) at anaerobic threshold were predictive of outcome on univariate analysis. On multivariate analysis, peak cardiac power and peak CO were predictive of outcome with peak cardiac power being the most powerful independent predictor of outcome (P=0.01).Conclusions-Peak cardiac power, measured noninvasively, is an independent predictor Of Outcome that can enhance the prognostic power of peak Vo(2) in the evaluation of patients with heart failure. (Circ Heart Fail. 2009;2:33-38.)</p
Covert collusion? American and South African relations during the Angolan civil war, 1974-1976
No full textThe traditional focus regarding the Angolan Civil War, 1974 – 1976, has been on the nature of Soviet and Cuban involvement, the American response to communist activities, and South Africa’s invasion. A point often mentioned, but rarely elaborated upon in the literature, is the degree to which the USA encouraged South Africa to intervene in the Angolan conflict. This paper investigates the extent and nature of American collusion with South Africa in the civil war, and the degree of complicity of senior American officials. The paper argues that on balance, the evidence suggests that senior elements of the United States executive branch, covertly and informally, colluded with South Africa. South African politicians overestimated the depth and extent of American support for its intervention, and when the USA ceased its assistance, they felt betrayed by Kissinger
Artificial neural networks for mapping regional-scale upland vegetation from high spatial resolution imagery
No full textUpland vegetation represents an important resource that requires frequent monitoring. However, the heterogeneous nature of upland vegetation and lack of ground data require classification techniques that have a high degree of generalization ability. This study investigates the use of artificial neural networks as a means of mapping upland vegetation from remotely sensed data. First, the optimum size of support to map upland vegetation was estimated as being less than 4m, which suggested that soft classification techniques and high spatial resolution IKONOS imagery were required. The use of high spatial resolution imagery for regional-scale areas has introduced new challenges to the remote sensing community, such as using limited ground data and mapping land-cover dynamics and variation over large areas. This work then investigated the utility of artificial neural networks ( ANN) for regional-scale upland vegetation from IKONOS imagery using limited ground data and to map unseen data from remote geographical locations. A Multiple Layer Perceptron was trained with pixels from an IKONOS image using early stopping; however, despite high classification accuracies when calculated for pixels from an area where training pixels were extracted, the networks did not produce high accuracies when applied to unseen data from a remote area
Artists’ Television: Interruptions–Interventions
No full textPartridge's chapter Investigates the incidence and approach of video art upon broadcast TV in the UK and Europe from Schum (1968) to TV Interventions, Channel 4 1990
Optimisation of the Anti-Trypanosoma brucei Activity of the Opioid Agonist U50488
No full textScreening of the Sigma-Aldrich Library of Pharmacologically Active Compounds (LOPAC) against cultured Trypanosoma brucei, the causative agent of African sleeping sickness, resulted in the identification of a number of compounds with selective antiproliferative activity over mammalian cells. These included (+)-(1R,2R)-U50488, a weak opioid agonist with an EC50 value of 59 nm as determined in our T. brucei in vitro assay reported previously. This paper describes the modification of key structural elements of U50488 to investigate structure-activity relationships (SAR) and to optimise the antiproliferative activity and pharmacokinetic properties of this compound.</p
Inhibitors of the kinase IspE:structure-activity relationships and co-crystal structure analysis
No full textEnzymes of the non-mevalonate pathway for isoprenoid biosynthesis are therapeutic targets for the treatment of important infectious diseases. Whereas this pathway is absent in humans, it is used by plants, many eubacteria and apicomplexan protozoa, including major human pathogens such as Plasmodium falciparum and Mycobacterium tuberculosis. Herein, we report on the design, preparation and biological evaluation of a new series of ligands for IspE protein, a kinase from this pathway. These inhibitors were developed for the inhibition of IspE from Escherichia coli, using structure-based design approaches. Structure-activity relationships (SARs) and a co-crystal structure of Aquifex aeolicus IspE bound to a representative inhibitor validate the proposed binding mode. The crystal structure shows that the ligand binds in the substrate-rather than the adenosine 5'-triphosphate (ATP)-binding pocket. As predicted, a cyclopropyl substituent occupies a small cavity not used by the substrate. The optimal volume occupancy of this cavity is explored in detail. In the co-crystal structure, a diphosphate anion binds to the Gly-rich loop, which normally accepts the triphosphate moiety of ATP. This structure provides useful insights for future structure-based developments of inhibitors for the parasite enzymes.</p
Interpreting transient photocurrents as a signature of the density of states distribution:the profound importance of the short-time decay
No full textWe present a study exploring the fidelity of recovery of the density of states from transient photocurrents for different distributions of traps based on computer simulation of transient photocurrent decay (TPC). The most important result of the work is that much of the information on the form of the density of states (DOS) over an energy range of up to 0.5 eV depth, is contained in the detailed form of the initial decay of the photocurrent on a timescale <10-10 s in which we might expect only the shallowest traps to have an affect. To illustrate this point, we demonstrate that substantially different DOS distributions (exponential, Gaussian, rectangular) can be made to give apparently identical TPC decays over several orders of magnitude of time after an initial trapping phase in which there are only small differences in the shape of the response. Recombination effects may also be included. Nevertheless, using a Fourier transform TPC analytical method we can make a distinction between such DOS distributions, provided the short-time initial decay is included
Future integration of silicon electronics with miniature piezoelectric ultrasonic transducers and arrays
No full textThe long-established pace of progress in semiconductor electronics, expressed by Moore's Law, has led to new opportunities in medical ultrasound imaging. Traditionally, ultrasound systems have separated the transducer array from most of the electronic instrumentation, with multicore physical cabling in between. This avoids problems with electrical power, functional density, and communication bandwidth. However, it is far from ideal in terms of cost, ergonomics, and the need to interface instrumentation and the transducer with the cable, and it causes particular difficulties with miniature devices. Given these issues, and the relatively slow progress in front-end transducer technology, integration of the transducer with electronics is certain to increase, most likely at a pace governed by financial investment, development of electronics for other applications, and the realisation of high volume ultrasound applications. This paper therefore considers motivations for increased integration, technical barriers, and relevant new techniques, particularly related to microelectromechanical systems (MEMS). Increased integration will rely on advances in integrated circuit (IC) electronics, device assembly, and microsystems engineering, with key constraints being the packaging of a system in a small volume and the power supply. System partitioning will determine where functionality will reside physically within the imaging hardware and software. This paper considers relevant recent developments in academic research and industry, with a particular focus on medical applications. IC design is important because it defines parameters such as power consumption. 45 nm ICs are now in high volume production but the present relatively small ultrasound market makes adoption difficult. Ingenuity in exploiting existing technology cost-effectively and bespoke engineering where required are likely to be important for integration of piezoelectric material with electronics technology and functionality will correspond with different layers in a device. In this paper, examples are selected from the authors' work to illustrate progress and suggest how MEMS roadmaps and application demands may relate to future systems
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