6,606 research outputs found

    Teaching Teachers for the Future (TTF) Project: Development of the TTF TPACK survey instrument

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    This paper presents a summary of the key findings of the TTF TPACK Survey developed and administered for the Teaching the Teachers for the Future (TTF) Project implemented in 2011. The TTF Project, funded by an Australian Government ICT Innovation Fund grant, involved all 39 Australian Higher Education Institutions which provide initial teacher education. TTF data collections were undertaken at the end of Semester 1 (T1) and at the end of Semester 2 (T2) in 2011. A total of 12881 participants completed the first survey (T1) and 5809 participants completed the second survey (T2). Groups of like-named items from the T1 survey were subject to a battery of complementary data analysis techniques. The psychometric properties of the four scales: Confidence - teacher items; Usefulness - teacher items; Confidence - student items; Usefulness- student items, were confirmed both at T1 and T2. Among the key findings summarised, at the national level, the scale: Confidence to use ICT as a teacher showed measurable growth across the whole scale from T1 to T2, and the scale: Confidence to facilitate student use of ICT also showed measurable growth across the whole scale from T1 to T2. Additional key TTF TPACK Survey findings are summarised

    A note on the calculation of the effective range

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    The closed form of the first order non-linear differential equation that is satisfied by the effective range within the variable phase formulation of scattering theory is discussed. It is shown that the conventional method of determining the effective range, by fitting a numerical solution of the Schr\"odinger equation to known asymptotic boundary conditions, can be modified to include the first order contribution of a long range interaction.Comment: 4 page

    Self-aligned fabrication process for silicon quantum computer devices

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    We describe a fabrication process for devices with few quantum bits (qubits), which are suitable for proof-of-principle demonstrations of silicon-based quantum computation. The devices follow the Kane proposal to use the nuclear spins of 31P donors in 28Si as qubits, controlled by metal surface gates and measured using single electron transistors (SETs). The accurate registration of 31P donors to control gates and read-out SETs is achieved through the use of a self-aligned process which incorporates electron beam patterning, ion implantation and triple-angle shadow-mask metal evaporation

    The variable phase method used to calculate and correct scattering lengths

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    It is shown that the scattering length can be obtained by solving a Riccati equation derived from variable phase theory. Two methods of solving it are presented. The equation is used to predict how long-range interactions influence the scattering length, and upper and lower bounds on the scattering length are determined. The predictions are compared with others and it is shown how they may be obtained from secular perturbation theory.Comment: 7 pages including 3 figure

    Fractal-like Distributions over the Rational Numbers in High-throughput Biological and Clinical Data

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    Recent developments in extracting and processing biological and clinical data are allowing quantitative approaches to studying living systems. High-throughput sequencing, expression profiles, proteomics, and electronic health records are some examples of such technologies. Extracting meaningful information from those technologies requires careful analysis of the large volumes of data they produce. In this note, we present a set of distributions that commonly appear in the analysis of such data. These distributions present some interesting features: they are discontinuous in the rational numbers, but continuous in the irrational numbers, and possess a certain self-similar (fractal-like) structure. The first set of examples which we present here are drawn from a high-throughput sequencing experiment. Here, the self-similar distributions appear as part of the evaluation of the error rate of the sequencing technology and the identification of tumorogenic genomic alterations. The other examples are obtained from risk factor evaluation and analysis of relative disease prevalence and co-mordbidity as these appear in electronic clinical data. The distributions are also relevant to identification of subclonal populations in tumors and the study of the evolution of infectious diseases, and more precisely the study of quasi-species and intrahost diversity of viral populations

    Bias spectroscopy and simultaneous SET charge state detection of Si:P double dots

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    We report a detailed study of low-temperature (mK) transport properties of a silicon double-dot system fabricated by phosphorous ion implantation. The device under study consists of two phosphorous nanoscale islands doped to above the metal-insulator transition, separated from each other and the source and drain reservoirs by nominally undoped (intrinsic) silicon tunnel barriers. Metallic control gates, together with an Al-AlOx single-electron transistor, were positioned on the substrate surface, capacitively coupled to the buried dots. The individual double-dot charge states were probed using source-drain bias spectroscopy combined with non-invasive SET charge sensing. The system was measured in linear (VSD = 0) and non-linear (VSD 0) regimes allowing calculations of the relevant capacitances. Simultaneous detection using both SET sensing and source-drain current measurements was demonstrated, providing a valuable combination for the analysis of the system. Evolution of the triple points with applied bias was observed using both charge and current sensing. Coulomb diamonds, showing the interplay between the Coulomb charging effects of the two dots, were measured using simultaneous detection and compared with numerical simulations.Comment: 7 pages, 6 figure

    Preparation of anti-vicinal amino alcohols: asymmetric synthesis of D-erythro-Sphinganine, (+)-spisulosine and D-ribo-phytosphingosine

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    Two variations of the Overman rearrangement have been developed for the highly selective synthesis of anti-vicinal amino alcohol natural products. A MOM-ether directed palladium(II)-catalyzed rearrangement of an allylic trichloroacetimidate was used as the key step for the preparation of the protein kinase C inhibitor D-erythro-sphinganine and the antitumor agent (+)-spisulosine, while the Overman rearrangement of chiral allylic trichloroacetimidates generated by asymmetric reduction of an alpha,beta-unsaturated methyl ketone allowed rapid access to both D-ribo-phytosphingosine and L-arabino-phytosphingosine

    Validity of Criteria for Dementia in Older People With Intellectual Disability

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    Objective: Valid definitions of dementia should discriminate dementia from other forms of cognitive impairment such as intellectual disability (ID). We aimed to evaluate the usefulness of criteria for dementia and mild cognitive impairment (MCI) in ID, including predictive validity, and inter-rater reliability. / Method: We assessed 222 participants in a survey of older adults with ID without Down syndrome at two time points for dementia (T1 and T2). Mean follow-up period was 2.9 years. Dementia diagnoses were made according to International Classification of Diseases, Tenth Revision, Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition), Diagnostic criteria for psychiatric disorders for use with adults with learning disabilities (DC-LD) criteria. At follow-up (T2), raters were blind to initial diagnosis. Predictive validity was determined by comparing odds ratios (ORs) of death, or of having a “poor outcome” (i.e., either dying or being diagnosed with dementia at T2). / Results: All dementia criteria showed substantial inter-rater reliability (Îș > 0.68) and high specificity (∌95%). Dementia cases at T1 were more likely to have died at T2 than those with no dementia (33.3% versus 14.9%; OR: 2.85; 95% confidence interval (95% CI): 1.12–7.22) and to have a “poor outcome” (77.8% versus 27.6%; OR: 9.18; 95% CI: 3.43–24.53). At least two dementia cases at T1 were false positives. Those with “MCI” at T1 were similar to “no dementia” cases in terms of poor outcomes at T2. / Conclusion: Dementia diagnostic criteria show substantial reliability and satisfactory validity in ID. The diagnoses were, however, less stable than in the general population and some caution is advisable in those with more severe ID or additional sensory disability. MCI definitions require further consideration in the ID population
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