1,491 research outputs found

    Social Presence, Identity, and Online Learning Research: Research Development and Needs

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    Scholars across many disciplines have grappled with questions of what it means for a person to be and interact online. Who are we when we go online? How do others know we are there and how do they perceive us? Within the context of online learning, scholarly questions tend to reflect more specific concerns focused on how well people can learn in a setting limited to mediated interactions lacking various communication cues. For example, how can a teacher and students come to know each other if they cannot see each other? How can they effectively understand and communicate with each other if they are separated by space and, in many instances, time? These concerns are related to issues of social presence and identity, both of which are complex, multi-faceted, closely interrelated constructs

    Luminosities of H alpha emitting regions in a pair of interacting galaxies in the Bootes void

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    Luminosities of H alpha emission from a pair of interacting galaxies in the low density environment of the Bootes void are presented. CG 692 (IRAS 1519+5050) has an H alpha luminosity of 2 x 10(exp 42) ergs s(exp -1), indicating a star formation rate of 18.4 solar mass yr(exp -1). Individual extranuclear H alpha regions have luminosities of approximately 10(exp 40) ergs s(exp -1). These luminosities are similar to those found for H II regions in bright, late-type galaxies in more densely populated parts of the Universe

    Marketing, the past and corporate heritage

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    Argues for a more expansive conceptualisation of the past’s relevance in, and for, marketing. Such a differentiated approach to the past is pregnant with possibilities in terms of advancing scholarship apropos temporal agency in marketing along with consumption practices. Symptomatic of this perspective is the increased mindfulness of the rich palate of past-related concepts. Significantly, the corporate heritage notion - because of its omni-temporal nature - represents a distinct and meaningful vector on the past by coalescing the past, present and future into a new type of temporality. As such, the authors reason this expansive conceptualisation of ‘the past-in-marketing’ is both timely and efficacious. Whilst sensitive of the importance of the historical method in marketing and the history of marketing scholarship and practice per se. This broader marketing approach to and of the past highlights the ideational and material manifestations of the past-in-the-present and an envisaged past-in-the future

    Properties of Ly-alpha and Gamma Ray Burst selected starbursts at high redshifts

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    Selection of starbursts through either deep narrow band imaging of redshifted Ly-alpha emitters, or localisation of host galaxies of gamma-ray bursts both give access to starburst galaxies that are significantly fainter than what is currently available from selection techniques based on the continuum (such as Lyman-break selection). We here present results from a survey for Ly-alpha emitters at z=3, conducted at the European Southern Observatory's Very Large Telescope. Furthermore, we briefly describe the properties of host galaxies of gamma-ray bursts at z>2. The majority of both Ly-alpha and gamma-ray burst selected starbursts are fainter than the flux limit of the Lyman-break galaxy sample, suggesting that a significant fraction of the integrated star formation at z~3 is located in galaxies at the faint end of the luminosity function.Comment: invited talk, 6 pages, 3 figures, to appear in ``Starbursts from 30 Doradus to Lyman Break Galaxies'', eds. R. de Grijs, R. M. Gonzalez Delgado, Astrophysics & Space Science Library Series, Kluwer (in press

    A companion to a quasar at redshift 4.7

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    There is a growing consensus that the emergence of quasars at high redshifts is related to the onset of galaxy formation, suggesting that the detection of concentrations of gas accompanying such quasars should provide clues about the early history of galaxies. Quasar companions have been recently identified at redshifts up to z≈3z \approx 3. Here we report observations of Lyman-α\alpha emission (a tracer of ionised hydrogen) from the companion to a quasar at zz=4.702, corresponding to a time when the Universe was less than ten per cent of its present age. We argue that most of the emission arises in a gaseous nebula that has been photoionised by the quasar, but an additional component of continuum light -perhaps quasar light scattered from dust in the companion body, or emission from young stars within the nebula- appears necessary to explain the observations. These observations may be indicative of the first stages in the assembly of galaxy-sized structures.Comment: 8 pages, 4 figures, plain LaTeX. Accepted for publication in Natur

    "We did not know what was wrong"-Barriers along the care cascade among hospitalized adolescents with HIV in Gaborone, Botswana

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    High mortality among adolescents with HIV reflects delays and failures in the care cascade. We sought to elucidate critical missed opportunities and barriers to care among adolescents hospitalized with HIV at Botswana's tertiary referral hospital. We enrolled all HIV-infected adolescents (aged 10-19 years) hospitalized with any diagnosis other than pregnancy from July 2015 to January 2016. Medical records were reviewed for clinical variables and past engagement in care. Semi-structured interviews of the adolescents (when feasible) and their caregivers explored delays and barriers to care. Twenty-one eligible adolescents were identified and 15 were enrolled. All but one were WHO Clinical Stage 3 or 4. Barriers to diagnosis included lack of awareness about perinatal HIV infection, illness or death of the mother, and fear of discrimination. Barriers to adherence to antiretroviral therapy included nondisclosure, isolation, and mental health concerns. The number of hospitalized HIV-infected adolescents was lower than expected. However, among those hospitalized, the lack of timely diagnosis and subsequent gaps in the care cascade elucidated opportunities to improve outcomes and quality of life for this vulnerable group
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