Critical thinking in asynchronous online discussions: examining the role of the student facilitator

This paper is part of a larger study that investigates the types of facilitation techniques exhibited by student facilitators and how these techniques may foster in-depth levels of critical thinking in asynchronous online discussions. Data were collected from ten discussion forums, involving education major students. The top 30% of forums in terms of the most number of in-depth critical thinking incidences were first identified (i.e., higher-level group). Next, the bottom 30% forums were identified as the lower-level critical thinking group. Results indicated that student facilitators in the higher-level group acknowledged the participants’ contributions, and posted more questions than their counterparts in the lower-level forums. Facilitators in the high-level group also tended to pose questions throughout the entire discussion, unlike those in the lower-level group who only posted questions at the start of the discussion. Six types of questioning techniques were found. Directions for future research are proposed.postprin

Actively deployable mobile services for adaptive web access

2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

A review of 10 children on continuous ambulatory peritoneal dialysis

The experience of continuous ambulatory peritoneal dialysis in children of the Queen Mary Hospital for the past 11 years was reviewed. Seven boys and three girls (aged 4.3 to 15.9 years) were treated for a mean of 27 months (range 5 to 58 months). There was significant biochemical improvement and patients led an active life on continuous ambulatory peritoneal dialysis. The commonest complications were peritonitis, occurring on average once per 10 patient-months and mostly due to Staphylococcus spp. The median catheter survival time was 30 months. There were two technique failures due to fungal peritonitis which necessitated transfer to haemodialysis due to fungal peritonitis. The only mortality was due to concurrent cardiac disease. This review supports that children with renal failure in Hong Kong can be maintained on long term dialysis with a reasonable quality of life. However, significant morbidity due to infective and mechanical complications still exists. Continuous ambulatory peitonitis dialysis remains a temporary treatment modality while patients are waiting for renal transplantation.published_or_final_versio

Left ventricular mechanics in repaired tetralogy of Fallot with and without pulmonary valve replacement: analysis by three-dimensional speckle tracking echocardiography

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Left ventricular torsional mechanics and myocardial iron load in beta-thalassaemia major: a potential role of titin degradation

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Dynamic dyssynchrony and impaired contractile reserve of the left ventricle in beta-thalassaemia major: an exercise echocardiographic study

BACKGROUND: Performance of the left ventricle during exercise stress in thalassaemia patients is uncertain. We aimed to explore the phenomenon of dynamic dyssynchrony and assess contractile reserve in patients with beta-thalassaemia major and determine their relationships with myocardial iron load. METHODS AND RESULTS: Thirty-two thalassaemia patients (16 males), aged 26.8+/-6.9 years, without heart failure and 17 healthy controls were studied. Their left ventricular (LV) volumes, ejection fraction, systolic dyssynchrony index (SDI), and myocardial acceleration during isovolumic LV contraction (IVA) were determined at rest and during submaximal bicycle exercise testing using 3-dimensional and tissue Doppler echocardiography. Myocardial iron load as assessed by T2* cardiac magnetic resonance in patients were further related to indices of LV dyssynchrony and contractile reserve. At rest, patients had significantly greater LV SDI (p4.6%, control+2SD) increased from baseline 25% to 84% in patients. Delta SDI(exercise-baseline) correlated with exercise-baseline differences in LV ejection fraction (p<0.001) and stroke volume (p = 0.006). Compared with controls, patients had significantly less exercise-induced increase in LV ejection fraction, cardiac index, and IVA (interaction, all p<0.05) and had impaired contractile reserve as reflected by the gentler IVA-heart rate slope (p = 0.018). Cardiac T2* in patients correlated with baseline LV SDI (r = -0.44, p = 0.011) and IVA-heart rate slope (r = 0.36, p = 0.044). CONCLUSIONS: Resting LV dyssynchrony is associated with myocardial iron load. Exercise stress further unveils LV dynamic dyssynchrony and impaired contractile reserve in patients with beta-thalassaemia major.published_or_final_versio

The fetal mouse is a sensitive genotoxicity model that exposes lentiviral-associated mutagenesis resulting in liver oncogenesis

This article is available open access through the publisher’s website at the link below. Copyright @ 2013 The American Society of Gene & Cell Therapy.Genotoxicity models are extremely important to assess retroviral vector biosafety before gene therapy. We have developed an in utero model that demonstrates that hepatocellular carcinoma (HCC) development is restricted to mice receiving nonprimate (np) lentiviral vectors (LV) and does not occur when a primate (p) LV is used regardless of woodchuck post-translation regulatory element (WPRE) mutations to prevent truncated X gene expression. Analysis of 839 npLV and 244 pLV integrations in the liver genomes of vector-treated mice revealed clear differences between vector insertions in gene dense regions and highly expressed genes, suggestive of vector preference for insertion or clonal outgrowth. In npLV-associated clonal tumors, 56% of insertions occurred in oncogenes or genes associated with oncogenesis or tumor suppression and surprisingly, most genes examined (11/12) had reduced expression as compared with control livers and tumors. Two examples of vector-inserted genes were the Park 7 oncogene and Uvrag tumor suppressor gene. Both these genes and their known interactive partners had differential expression profiles. Interactive partners were assigned to networks specific to liver disease and HCC via ingenuity pathway analysis. The fetal mouse model not only exposes the genotoxic potential of vectors intended for gene therapy but can also reveal genes associated with liver oncogenesis.Imperial College London, the Wellcome Trust, and Brunel University

Binary orbits as the driver of γ-ray emission and mass ejection in classical novae

Classical novae are the most common astrophysical thermonuclear explosions, occurring on the surfaces of white dwarf stars accreting gas from companions in binary star systems. Novae typically expel �10,000 solar masses of material at velocities exceeding 1,000 km/s. However, the mechanism of mass ejection in novae is poorly understood, and could be dominated by the impulsive flash of the thermonuclear runaway, prolonged optically thick winds, or binary interaction with the nova envelope. Classical novae are now routinely detected in GeV gamma-rays, suggesting that relativistic particles are accelerated by strong shocks in nova ejecta. Here we present high-resolution imaging of the gamma-ray-emitting nova V959 Mon at radio wavelengths, showing that its ejecta were shaped by binary motion: some gas was expelled rapidly along the poles as a wind from the white dwarf, while denser material drifted out along the equatorial plane, propelled by orbital motion. At the interface between the equatorial and polar regions, we observe synchrotron emission indicative of shocks and relativistic particle acceleration, thereby pinpointing the location of gamma-ray production. Binary shaping of the nova ejecta and associated internal shocks are expected to be widespread among novae, explaining why many novae are gamma-ray emitters