Peer Learning in Virtual Schools

This is the published version. Copyright 2014 Canadian Network for Innovation in EducationThis article is about peer-to-peer learning amongst students within K–12 virtual schools. This issue is examined through a case study of experiences of three students with disabilities enrolled in one virtual school and that of their parents, teachers, and school administrators. The article is framed around variability in learners’ aptitudes for peer-to-peer learning, in the design of the learning environment and what it affords for interpersonal interactions, and in the context where that learning design is implemented (and whether or not it promotes peer-to-peer learning). Each of these areas of variability impacted whether or not peer-to-peer learning occurred

Ultra-fast calorimetry study of Ge₂Sb₂Te₅ crystallization between dielectric layers

Phase changes in chalcogenides such as Ge2Sb2Te5 can be exploited in non-volatile random-access memory, with fast crystallization crucial for device operation. Ultra-fast differential scanning calorimetry, heating at rates up to 40,000K s-1, has been used to study the crystallization of amorphous Ge2Sb2Te5 with and without sandwich layers of ZnS-SiO2. At heating rates up to 1000K s-1, the sandwich layers retard crystallization, an effect attributed to crystallization-induced stress. At greater heating rates (>or = 5000K s-1), and consequently higher crystallization temperatures, the stress is relaxed, and sandwich layers catalyze crystallization. Implications for memory-device performance are discussed

The Scaled Arrival of K-12 Online Education: Emerging Realities and Implications for the Future of Education

Bioinfo PublicationsDramatic increases in K—12 online education for all students, including those in traditionally underserved populations, necessi2 tate a reconceptualization in the way educators plan and implement instruction. In this article the authors examine the complex array of variables and implementation models that must be accounted for during the pivot from a purely brick-and-mortar educational sys2 tem to one that makes use of both virtual and blended environ2 ments. The authors call for enhanced emphasis on instructional goals and design principles, rather than the capabilities of available technology. They conclude that educational leaders and researchers must play a role in three key areas: using technology to enhance the accessibility and usability of curricular materials to meet the needs of different types of learners, advancing the understanding and practices of in-service and pre-service teachers through preparation that focuses on online learning, and fostering collaboration between educational researchers and technology innovators and developers to build a research base that will inform K—12 online education

Scotland, Catalonia and the “right” to self-determination: a comment suggested by Kathryn Crameri’s “Do Catalans Have the Right to Decide?

No abstract available

Slopes To Prevent Trapping of Bubbles in Microfluidic Channels

The idea of designing a microfluidic channel to slope upward along the direction of flow of the liquid in the channel has been conceived to help prevent trapping of gas bubbles in the channel. In the original application that gave rise to this idea, the microfluidic channels are parts of micro-capillary electrophoresis (microCE) devices undergoing development for use on Mars in detecting compounds indicative of life. It is necessary to prevent trapping of gas bubbles in these devices because uninterrupted liquid pathways are essential for sustaining the electrical conduction and flows that are essential for CE. The idea is also applicable to microfluidic devices that may be developed for similar terrestrial microCE biotechnological applications or other terrestrial applications in which trapping of bubbles in microfluidic channels cannot be tolerated. A typical microCE device in the original application includes, among other things, multiple layers of borosilicate float glass wafers. Microfluidic channels are formed in the wafers, typically by use of wet chemical etching. The figure presents a simplified cross section of part of such a device in which the CE channel is formed in the lowermost wafer (denoted the channel wafer) and, according to the present innovation, slopes upward into a via hole in another wafer (denoted the manifold wafer) lying immediately above the channel wafer. Another feature of the present innovation is that the via hole in the manifold wafer is made to taper to a wider opening at the top to further reduce the tendency to trap bubbles. At the time of reporting the information for this article, an effort to identify an optimum technique for forming the slope and the taper was in progress. Of the techniques considered thus far, the one considered to be most promising is precision milling by use of femtosecond laser pulses. Other similar techniques that may work equally well are precision milling using a focused ion beam, or a small diamond-tipped drill bit

Reviews

The following publications have been reviewed by the mentioned authors;Beginning Graphical Communication by M. Jordan, B. Hawtin and A. Neil, reviewed by John LeesArt Related Topics by Bob Nunn and Chris Locke, reviewed by A. CharltonHandbook for Art and Design Students by Robin Jesson, reviewed by John LancasterDrawing and Cognition Descriptive and Experimental Studies of Graphic Production Processes by Peter Van Sommers, reviewed by Pamela M. SchenkThe Student's Guide to Western Calligraphy an Illustrated Survey by Joyce Irene Whalley, reviewed by John LancasterSource Directory for Authentic Indian, Eskimo and Aleut Arts and Crafts by the Indian Arts and Crafts BoardMarianne Straub by Mary Schoeser, reviewed by Kim GreerMisha Black by Avril Blake, reviewed by Kim Greer'Working in Crafts' - A National Survey by the Crafts Council, reviewed by L. SayerDirectory of Design Expertise by the Design Council, reviewed by R. Smit

Some highlights of research on aging with invertebrates, 2010

This annual review focuses on invertebrate model organisms, which continue to yield fundamental new insights into mechanisms of aging. This year, the budding yeast has been used to understand how asymmetrical partitioning of cellular constituents at cell division can produce a rejuvenated offspring from an aging parent. Blocking of sensation of carbon dioxide is shown to extend fly lifespan and to mediate the lifespan-shortening effect of sensory exposure to fermenting yeast. A new study of daf-16, the key forkhead transcription factor that mediates extension of lifespan by mutants in the insulin-signalling pathway in Caenorhabditis elegans, demonstrates that expression of tissue-specific isoforms with different patterns of response to upstream signalling mediates the highly pleiotropic effects of the pathway on lifespan and other traits. A new approach to manipulating mitochondrial activity in Drosophila, by introducing the yeast NADH-ubiquinone oxidoreductase, shows promise for understanding the role of mitochondrial reactive oxygen species in aging. An exciting new study of yeast and mammalian cells implicates deterioration of the nuclear pore, and consequent leakage of cytoplasmic components into the nucleus, as an important cause of aging in postmitotic tissues. Loss of, or damage to, chromosome-associated histones is also implicated in the determination of lifespan in yeast, worms and fruit flies. The relationship between functional aging, susceptibility to aging-related disease and lifespan itself are explored in two studies in C. elegans, the first examining the role of dietary restriction and reduced insulin signalling in cognitive decline and the second profiling aggregation of the proteome during aging. The invertebrates continue to be a power house of discovery for future work in mammals

Secondary and tertiary budbreak release is enhanced by extended dormancy chilling in 'Shiraz' grapevines

Limited information exists regarding the dormancy of secondary and tertiary buds within the compound bud of grapevines. We were interested to evaluate how extended chilling duration would affect the budbreak percentage of all three bud orders within the compound bud. Dormant potted 'Shiraz' grapevines, with thirty retained buds per vine, were placed in a cool room at 4 °C over a 20-month period to extend dormancy. Vines were then systematically removed over five dates and placed in a controlled growth environment to assess budbreak percentages and cane tissue concentrations of abscisic acid and cytokinins. Budbreak was hastened by at least 13 d with vines receiving any extra chilling compared to no initial chilling. Furthermore, the firstly observed correlative inhibition of basal buds was apparently removed with chilling. Removal of correlative inhibition within the compound bud with increased chilling duration was also observed with the increases of secondary (doubles) and tertiary (triples) buds breaking simultaneously with the primary bud at each node. This resulted in 91 % of the nodes having two developing shoots and 56 % of the nodes presenting three developing shoots by the end of the experiment. Furthermore, a sigmoidal relationship between percent secondary buds and chilling duration was observed. Possible phytohormone connections were observed with the decline of ABA as secondary and tertiary buds broke at 414 d of chilling and depletion of the CKs, which coincided with the greatest rate of primary bud break after 242 d of chilling. Other possible involvement of ABA and Cis-type cytokinin interactions with secondary and tertiary bud dormancy is discussed. The results suggest future investigations into secondary and tertiary bud release within the grapevine using similar techniques may help to better understand the biochemical mechanisms associated with dormancy

The implications of brexit for UK agriculture

A multi-authored briefing paper prepared for the Yorkshire Agricultural Society/The Farmer Scientist Network to inform the debate on the EU referendum in relation to agriculture