170 research outputs found

    Learning from the early adopters: developing the digital practitioner

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    This paper explores how Sharpe and Beetham’s Digital Literacies Framework which was derived to model students’ digital literacies, can be applied to lecturers’ digital literacy practices. Data from a small-scale phenomenological study of higher education lecturers who used Web 2.0 in their teaching and learning practices are used to examine if this pyramid model represents their motivations for adopting technology-enhanced learning in their pedagogic practices. The paper argues that whilst Sharpe and Beetham’s model has utility in many regards, these lecturers were mainly motivated by the desire to achieve their pedagogic goals rather than by a desire to become a digital practitioner

    Bodies, technologies and action possibilities: when is an affordance?

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    Borrowed from ecological psychology, the concept of affordances is often said to offer the social study of technology a means of re-framing the question of what is, and what is not, ‘social’ about technological artefacts. The concept, many argue, enables us to chart a safe course between the perils of technological determinism and social constructivism. This article questions the sociological adequacy of the concept as conventionally deployed. Drawing on ethnographic work on the ways technological artefacts engage, and are engaged by, disabled bodies, we propose that the ‘affordances’ of technological objects are not reducible to their material constitution but are inextricably bound up with specific, historically situated modes of engagement and ways of life

    Integrated tunneling sensor for nanoelectromechanical systems

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    Transducers based on quantum mechanical tunneling provide an extremely sensitive sensor principle, especially for nanoelectromechanical systems. For proper operation a gap between the electrodes of below 1nm is essential, requiring the use of structures with a mobile electrode. At such small distances, attractive van der Waals and capillary forces become sizable, possibly resulting in snap-in of the electrodes. The authors present a comprehensive analysis and evaluation of the interplay between the involved forces and identify requirements for the design of tunnelingsensors. Based on this analysis, a tunnelingsensor is fabricated by Si micromachiningtechnology and its proper operation is demonstrated

    Comprehensive characterization of molecular interactions based on nanomechanics

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    Molecular interaction is a key concept in our understanding of the biological mechanisms of life. Two physical properties change when one molecular partner binds to another. Firstly, the masses combine and secondly, the structure of at least one binding partner is altered, mechanically transducing the binding into subsequent biological reactions. Here we present a nanomechanical micro-array technique for bio-medical research, which not only monitors the binding of effector molecules to their target but also the subsequent effect on a biological system in vitro. This label-free and real-time method directly and simultaneously tracks mass and nanomechanical changes at the sensor interface using micro-cantilever technology. To prove the concept we measured lipid vesicle (approximately 748*10(6) Da) adsorption on the sensor interface followed by subsequent binding of the bee venom peptide melittin (2840 Da) to the vesicles. The results show the high dynamic range of the instrument and that measuring the mass and structural changes simultaneously allow a comprehensive discussion of molecular interactions

    Claudin-1 Is a p63 Target Gene with a Crucial Role in Epithelial Development

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    The epidermis of the skin is a self-renewing, stratified epithelium that functions as the interface between the human body and the outer environment, and acts as a barrier to water loss. Components of intercellular junctions, such as Claudins, are critical to maintain tissue integrity and water retention. p63 is a transcription factor essential for proliferation of stem cells and for stratification in epithelia, mutated in human hereditary syndromes characterized by ectodermal dysplasia. Both p63 and Claudin-1 null mice die within few hours from birth due to dehydration from severe skin abnormalities. These observations suggested the possibility that these two genes might be linked in one regulatory pathway with p63 possibly regulating Claudin-1 expression. Here we show that silencing of ΔNp63 in primary mouse keratinocytes results in a marked down-regulation of Claudin-1 expression (−80%). ΔNp63α binds in vivo to the Claudin-1 promoter and activates both the endogenous Claudin-1 gene and a reporter vector containing a –1.4 Kb promoter fragment of the Claudin-1 gene. Accordingly, Claudin-1 expression was absent in the skin of E15.5 p63 null mice and natural p63 mutant proteins, specifically those found in Ankyloblepharon–Ectodermal dysplasia–Clefting (AEC) patients, were indeed altered in their capacity to regulate Claudin-1 transcription. This correlates with deficient Claudin-1 expression in the epidermis of an AEC patient carrying the I537T p63 mutation. Notably, AEC patients display skin fragility similar to what observed in the epidermis of Claudin-1 and p63 null mice. These findings reinforce the hypothesis that these two genes might be linked in a common regulatory pathway and that Claudin-1 may is an important p63 target gene involved in the pathogenesis of ectodermal dysplasias

    Facilitation or Competition? Tree Effects on Grass Biomass across a Precipitation Gradient

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    Savanna ecosystems are dominated by two distinct plant life forms, grasses and trees, but the interactions between them are poorly understood. Here, we quantified the effects of isolated savanna trees on grass biomass as a function of distance from the base of the tree and tree height, across a precipitation gradient in the Kruger National Park, South Africa. Our results suggest that mean annual precipitation (MAP) mediates the nature of tree-grass interactions in these ecosystems, with the impact of trees on grass biomass shifting qualitatively between 550 and 737 mm MAP. Tree effects on grass biomass were facilitative in drier sites (MAP≤550 mm), with higher grass biomass observed beneath tree canopies than outside. In contrast, at the wettest site (MAP = 737 mm), grass biomass did not differ significantly beneath and outside tree canopies. Within this overall precipitation-driven pattern, tree height had positive effect on sub-canopy grass biomass at some sites, but these effects were weak and not consistent across the rainfall gradient. For a more synthetic understanding of tree-grass interactions in savannas, future studies should focus on isolating the different mechanisms by which trees influence grass biomass, both positively and negatively, and elucidate how their relative strengths change over broad environmental gradients. © 2013 Moustakas et al

    Real-Time, Real World Learning—Capitalising on Mobile Technology

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    This chapter explores the adoption of Web 2.0 technologies to promote active learning by students and to both mediate and enhance classroom instruction. Web 2.0 refers to open source, web-enabled applications (apps) that are driven by user-manipulated and user-generated content (Kassens-Noor, 2012). These apps are often rich in user participation, have dynamic content, and harness the collective intelligence of users (Chen, Hwang, & Wang, 2012). As such, these processes create “active, context based, personalised learning experiences” (Kaldoudi, Konstantinidis, & Bamidis, 2010, p. 130) that prioritise learning ahead of teaching. By putting the learner at the centre of the education process educators can provide environments that enhance employability prospects and spark a passion for learning that, hopefully, lasts a lifetime. As such, we critique an active learning approach that makes use of technology such as mobile applications (apps), Twitter, and augmented reality to enhance students’ real world learning. Dunlap and Lowenthal (2009) argue that social media can facilitate active learning as they recreate informal, free-flowing communications that allow students and academics to connect on a more emotional level. Furthermore, their use upskills students in the technical complexities of the digital world and also the specialised discourses that are associated with online participation, suitable for real world learning and working (Fig. 16.1). Three case studies explore the benefits of Web 2.0 processes. The first details the use of Twitter chats to connect students, academics, and industry professionals via online synchronous discussions that offer a number of benefits such as encouraging concise writing from students and maintaining on-going relationships between staff, students, and industry contacts. The second details a location-based mobile app that delivers content to students when they enter a defined geographical boundary linked to an area of a sports precinct. Finally, we explore the use of augmented reality apps to enhance teaching in Human Geography and Urban Studies

    A Membrane Fusion Protein αSNAP Is a Novel Regulator of Epithelial Apical Junctions

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    Tight junctions (TJs) and adherens junctions (AJs) are key determinants of the structure and permeability of epithelial barriers. Although exocytic delivery to the cell surface is crucial for junctional assembly, little is known about the mechanisms controlling TJ and AJ exocytosis. This study was aimed at investigating whether a key mediator of exocytosis, soluble N-ethylmaleimide sensitive factor (NSF) attachment protein alpha (αSNAP), regulates epithelial junctions. αSNAP was enriched at apical junctions in SK-CO15 and T84 colonic epithelial cells and in normal human intestinal mucosa. siRNA-mediated knockdown of αSNAP inhibited AJ/TJ assembly and establishment of the paracellular barrier in SK-CO15 cells, which was accompanied by a significant down-regulation of p120-catenin and E-cadherin expression. A selective depletion of p120 catenin effectively disrupted AJ and TJ structure and compromised the epithelial barrier. However, overexpression of p120 catenin did not rescue the defects of junctional structure and permeability caused by αSNAP knockdown thereby suggesting the involvement of additional mechanisms. Such mechanisms did not depend on NSF functions or induction of cell death, but were associated with disruption of the Golgi complex and down-regulation of a Golgi-associated guanidine nucleotide exchange factor, GBF1. These findings suggest novel roles for αSNAP in promoting the formation of epithelial AJs and TJs by controlling Golgi-dependent expression and trafficking of junctional proteins

    Promoting community socio-ecological sustainability through technology: A case study from Chile

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    The importance of community learning in effecting social change towards ecological sustainability has been recognised for some time. More recently, the use of Information and Communication Technology (ICT) tools to promote socio-ecological sustainability has been shown to have potential in community education for sustainable development (ESD). The effective design and use of technology for community learning implies an understanding of a range of cross- dimensional factors including: socio-cultural characteristics and needs of the target audience; considerations of available and culturally responsive types of technology; and non-formal pedagogical ESD strategies for community empowerment. In addition, both technology itself and social communities are dynamically evolving and complex entities. This article presents a case study which evaluated the potential of ICT for promoting ecological literacy and action competence amongst community members in southern Chile. The case study addressed the ecological deterioration of a lake, which is having deep social, economic, recreational and cultural implications locally. The authors’ research involved developing a theoret- ical framework for the design, implementation and use of ICT for community learning for sustainability. The framework was based on key ideas from ESD, ICT and community education, and was underpinned by a systems thinking approach to account for the dynamism and complexity of such settings. Activity theory provided a frame to address overarching socio-cultural elements when using technology as a mediating tool for community learning. The authors’ findings suggest that the use of an ICT tool, such as a website, can enhance ecological literacy in relation to a local socio-ecological issue
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