Promoting reflection in asynchronous virtual learning spaces: tertiary distance tutors' conceptions

Increasingly, universities are embedding reflective activities into the curriculum. With the growth in online tertiary education, how effectively is reflection being promoted or used in online learning spaces? Based on the notion that teachers’ beliefs will influence their approaches to teaching, this research sought to understand how a group of distance tutors at the UK Open University conceptualised reflection. It was hoped that these findings would illuminate their approaches to promoting reflection as part of their online pedagogies. Phenomenographic analysis indicated that these tutors conceptualised reflection in four qualitatively different ways. Furthermore, the data suggested that these educators held a combination of two conceptions: one that understood the origin of being reflective and one that understood the purpose of reflection. Analysis of structural aspects of these conceptions offered insight into tutors’ own perspectives for what is needed to make online learning environments fertile territory for reflective learning

Regulation of the Pax6 : Pax6(5a) mRNA ratio in the developing mammalian brain

BACKGROUND: Early in mammalian brain development cell proliferation generates a population of progenitor cells whose subsequent divisions produce increasing numbers of postmitotic neurons. Pax6 affects both processes and it has been suggested that this changing role is due at least in part to changes in the relative concentrations of its two main isoforms, (i) Pax6 and (ii) Pax6(5a), created by insertion of a 42 bp exon (exon 5a) into one of the two DNA-binding domains. Crucially, however, no previous study has determined whether the ratio between Pax6 and Pax6(5a) transcripts alters during mammalian neurogenesis in vivo. RESULTS: Using RNase protection assays, we show that Pax6 transcripts are 6–10 times more prevalent than Pax6(5a) transcripts early in neurogenesis in the murine telencephalon, diencephalon and hindbrain and that the ratio later falls significantly to about 3:1 in these regions. CONCLUSION: These changes in vivo are similar in magnitude to those shown previously to alter target gene activity in vitro and might, therefore, allow the single mammalian Pax6 gene to carry out different functions at different times in mammalian brain development

Positive autoregulation of the transcription factor Pax6 in response to increased levels of either of its major isoforms, Pax6 or Pax6(5a), in cultured cells

<p>Abstract</p> <p>Background</p> <p>Pax6 is a transcription factor essential for normal development of the eyes and nervous system. It has two major isoforms, Pax6 and Pax6(5a), and the ratios between their expression levels vary within narrow limits. We tested the effects of overexpressing either one or other isoform on endogenous Pax6 expression levels in Neuro2A and NIH3T3 cells.</p> <p>Results</p> <p>We found that both isoforms caused an up-regulation of endogenous Pax6 expression in cells with (Neuro2A) or without (NIH3T3) constitutive Pax6 expression. Western blots showed that cells stably transfected with constructs expressing either Pax6 or Pax6(5a) contained raised levels of both Pax6 and Pax6(5a). Quantitative RT-PCR confirmed an increase in levels of <it>Pax6(5a) </it>mRNA in cells containing Pax6-expressing constructs and an increase in levels of <it>Pax6 </it>mRNA in cells containing Pax6(5a)-expressing constructs. The fact that the introduction of constructs expressing only one isoform increased the cellular levels of not only that isoform but also the other indicates that activation of the endogenous <it>Pax6 </it>locus occurred. The ratio between the levels of the two isoforms was maintained close to physiological values. The overexpression of either isoform in neuroblastoma (Neuro2A) cell lines also promoted morphological change and an increase in β-III-tubulin expression, indicating an increase in neurogenesis.</p> <p>Conclusion</p> <p>Our results demonstrate that Pax6 can up-regulate production of Pax6 protein from an entire intact endogenous <it>Pax6 </it>locus in its genomic environment. This adds to previous studies showing that Pax6 can up-regulate reporter expression driven by isolated <it>Pax6 </it>regulatory elements. Furthermore, our results suggest that an important function of positive feedback might be to stabilise the relative levels of Pax6 and Pax6(5a).</p

Dexterous Orbital Servicing System (DOSS)

The Dexterous Orbiter Servicing System (DOSS) is a dexterous robotic spaceflight system that is based on the manipulator designed as part of the Flight Telerobotics Servicer program for the Space Station Freedom and built during a 'technology capture' effort that was commissioned when the FTS was cancelled from the Space Station Freedom program. The FTS technology capture effort yielded one flight manipulator and the 1 g hydraulic simulator that had been designed as an integrated test tool and crew trainer. The DOSS concept was developed to satisfy needs of the telerobotics research community, the space shuttle, and the space station. As a flight testbed, DOSS would serve as a baseline reference for testing the performance of advanced telerobotics and intelligent robotics components. For shuttle, the DOSS, configured as a movable dexterous tool, would be used to provide operational flexibility for payload operations and contingency operations. As a risk mitigation flight demonstration, the DOSS would serve the International Space Station to characterize the end to end system performance of the Special Purpose Dexterous Manipulator performing assembly and maintenance tasks with actual ISSA orbital replacement units. Currently, the most likely entrance of the DOSS into spaceflight is a risk mitigation flight experiment for the International Space Station

Potato cyst nematodes Globodera rostochiensis and G. pallida

Innovate UK. Grant Number: 105653 (RESOLVE) Rural and Environment Science and Analytical Services Division. Grant Number: WP2.1 Scottish Funding Council. Grant Number: ODA GCRF XFC105Taxonomy: Phylum Nematoda; class Chromadorea; order Rhabditida; suborder Tylenchina; infraorder Tylenchomorpha; superfamily Tylenchoidea; family Heteroderidae; subfamily Heteroderinae; Genus Globodera. Biology: Potato cyst nematodes (PCN) are biotrophic, sedentary endoparasitic nematodes. Invasive (second) stage juveniles (J2) hatch from eggs in response to the presence of host root exudates and subsequently locate and invade the host. The nematodes induce the formation of a large, multinucleate syncytium in host roots, formed by fusion of up to 300 root cell protoplasts. The nematodes rely on this single syncytium for the nutrients required to develop through a further three moults to the adult male or female stage. This extended period of biotrophy?between 4 and 6 weeks in total?is almost unparalleled in plant?pathogen interactions. Females remain at the root while adult males revert to the vermiform body plan of the J2 and leave the root to locate and fertilize the female nematodes. The female body forms a cyst that contains the next generation of eggs. Host range: The host range of PCN is limited to plants of the Solanaceae family. While the most economically important hosts are potato (Solanum tuberosum), tomato (Solanum lycopersicum), and aubergine (Solanum melongena), over 170 species of Solanaceae are thought to be potential hosts for PCN (Sullivan et al., 2007). Disease symptoms: Symptoms are similar to those associated with nutrient deficiency, such as stunted growth, yellowing of leaves and reduced yields. This absence of specific symptoms reduces awareness of the disease among growers. Disease control: Resistance genes (where available in suitable cultivars), application of nematicides, crop rotation. Great effort is put into reducing the spread of PCN through quarantine measures and use of certified seed stocks. Useful websites: Genomic information for PCN is accessible through WormBase ParaSite.Publisher PDFPeer reviewe

Normal ventral telencephalic expression of Pax6 is required for normal development of thalamocortical axons in embryonic mice

<p>Abstract</p> <p>Background</p> <p>In addition to its well-known expression in dorsal telencephalic progenitor cells, where it regulates cell proliferation and identity, the transcription factor Pax6 is expressed in some ventral telencephalic cells, including many postmitotic neurons. Its functions in these cells are unknown.</p> <p>Results</p> <p>We generated a new floxed allele of <it>Pax6 </it>and tested the consequences of a highly specific ventral telencephalic depletion of Pax6. We used the <it>Six3</it>^{<it>A1A2</it>}-<it>Cre </it>allele that drives production of Cre recombinase in a specific region of Pax6-expression close to the internal capsule, through which thalamic axons navigate to cerebral cortex. Depletion in this region caused many thalamic axons to take aberrant routes, either failing to turn normally into ventral telencephalon to form the internal capsule or exiting the developing internal capsule ventrally. We tested whether these defects might have resulted from abnormalities of two structural features proposed to guide thalamic axons into and through the developing internal capsule. First, we looked for the early pioneer axons that project from the region of the future internal capsule to the thalamus and are thought to guide thalamocortical axons to the internal capsule: we found that they are present in conditional mutants. Second, we examined the development of the corridor of Islet1-expressing cells that guides thalamic axons through ventral telencephalon and found that it was broader and less dense than normal in conditional mutants. We also examined corticofugal axons that are thought to interact with ascending thalamocortical axons, resulting in each set providing guidance to the other, and found that some are misrouted to lateral telencephalon.</p> <p>Conclusion</p> <p>These findings indicate that ventral telencephalic Pax6 is important for formation of the Islet1-expressing corridor and the thalamic and cortical axons that grow through it. We suggest that Pax6 might affect thalamic axonal growth indirectly via its effect on the corridor.</p

Mesothelioma mortality in Great Britain from 1968 to 2001.

BACKGROUND: The British mesothelioma register contains all deaths from 1968 to 2001 where mesothelioma was mentioned on the death certificate. AIMS: To present summary statistics of the British mesothelioma epidemic including summaries by occupation and geographical area. METHODS: Standardized mortality ratios (SMRs) were calculated for local authorities, unitary authorities and counties. Temporal trends in SMRs were also examined. Proportional mortality ratios (PMRs) were calculated using the Southampton (based on the 1980 standard occupational classification) coding scheme. Temporal trends in PMRs were also examined. RESULTS: The annual number of mesothelioma deaths has increased from 153 in 1968 to 1848 in 2001. Current deaths in males account for about 85% of the cases. The areas of West Dunbartonshire (SMR 637), Barrow-in-Furness (593), Plymouth (396) and Portsmouth (388) have the highest SMRs over the period 1981-2000. The occupations with the highest PMRs are metal plate workers (PMR 503), vehicle body builders (526), plumbers and gas fitters (413) and carpenters (388). CONCLUSIONS: These data reinforce earlier findings that geographical areas and occupations associated with high exposure to asbestos in the past continue to drive the mesothelioma epidemic in Great Britain. However, the trends over time suggest a change in the balance of risk away from traditional asbestos exposure industries to industries where one could describe the exposure as secondary, such as plumbers and gas fitters, carpenters, and electricians

Gravitational Radiation from Preheating with Many Fields

Parametric resonances provide a mechanism by which particles can be created just after inflation. Thus far, attention has focused on a single or many inflaton fields coupled to a single scalar field. However, generically we expect the inflaton to couple to many other relativistic degrees of freedom present in the early universe. Using simulations in an expanding Friedmann-Lema\^itre-Robertson-Walker spacetime, in this paper we show how preheating is affected by the addition of multiple fields coupled to the inflaton. We focus our attention on gravitational wave production--an important potential observational signature of the preheating stage. We find that preheating and its gravitational wave signature is robust to the coupling of the inflaton to more matter fields.Comment: 7 pages, 8 figures, v2 submission version, thank you for comments