34 research outputs found

    Crystal and melt inclusion timescales reveal the evolution of magma migration before eruption

    Get PDF
    Volatile element concentrations measured in melt inclusions are a key tool used to understand magma migration and degassing, although their original values may be affected by different re-equilibration processes. Additionally, the inclusion-bearing crystals can have a wide range of origins and ages, further complicating the interpretation of magmatic processes. To clarify some of these issues, here we combined olivine diffusion chronometry and melt inclusion data from the 2008 eruption of Llaima volcano (Chile). We found that magma intrusion occurred about 4 years before the eruption at a minimum depth of approximately 8 km. Magma migration and reaction became shallower with time, and about 6 months before the eruption magma reached 3–4 km depth. This can be linked to reported seismicity and ash emissions. Although some ambiguities of interpretation still remain, crystal zoning and melt inclusion studies allow a more complete understanding of magma ascent, degassing, and volcano monitoring data.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore)Published versio

    3,3′-Diindolylmethane Induces G1 Arrest and Apoptosis in Human Acute T-Cell Lymphoblastic Leukemia Cells

    Get PDF
    Certain bioactive food components, including indole-3-carbinol (I3C) and 3,3′-diindolylmethane (DIM) from cruciferous vegetables, have been shown to target cellular pathways regulating carcinogenesis. Previously, our laboratory showed that dietary I3C is an effective transplacental chemopreventive agent in a dibenzo[def,p]chrysene (DBC)-dependent model of murine T-cell lymphoblastic lymphoma. The primary objective of the present study was to extend our chemoprevention studies in mice to an analogous human neoplasm in cell culture. Therefore, we tested the hypothesis that I3C or DIM may be chemotherapeutic in human T-cell acute lymphoblastic leukemia (T-ALL) cells. Treatment of the T-ALL cell lines CCRF-CEM, CCRF-HSB2, SUP-T1 and Jurkat with DIM in vitro significantly reduced cell proliferation and viability at concentrations 8- to 25-fold lower than the parent compound I3C. DIM (7.5 µM) arrested CEM and HSB2 cells at the G1 phase of the cell cycle and 15 µM DIM significantly increased the percentage of apoptotic cells in all T-ALL lines. In CEM cells, DIM reduced protein expression of cyclin dependent kinases 4 and 6 (CDK4, CDK6) and D-type cyclin 3 (CCND3); DIM also significantly altered expression of eight transcripts related to human apoptosis (BCL2L10, CD40LG, HRK, TNF, TNFRSF1A, TNFRSF25, TNFSF8, TRAF4). Similar anticancer effects of DIM were observed in vivo. Dietary exposure to 100 ppm DIM significantly decreased the rate of growth of human CEM xenografts in immunodeficient SCID mice, reduced final tumor size by 44% and increased the apoptotic index compared to control-fed mice. Taken together, our results demonstrate a potential for therapeutic application of DIM in T-ALL

    Eaten out of house and home:impacts of grazing on ground-dwelling reptiles in Australian grasslands and grassy woodlands

    Get PDF
    Large mammalian grazers can alter the biotic and abiotic features of their environment through their impacts on vegetation. Grazing at moderate intensity has been recommended for biodiversity conservation. Few studies, however, have empirically tested the benefits of moderate grazing intensity in systems dominated by native grazers. Here we investigated the relationship between (1) density of native eastern grey kangaroos, Macropus giganteus, and grass structure, and (2) grass structure and reptiles (i.e. abundance, richness, diversity and occurrence) across 18 grassland and grassy Eucalyptus woodland properties in south-eastern Australia. There was a strong negative relationship between kangaroo density and grass structure after controlling for tree canopy cover. We therefore used grass structure as a surrogate for grazing intensity. Changes in grazing intensity (i.e. grass structure) significantly affected reptile abundance, reptile species richness, reptile species diversity, and the occurrence of several ground-dwelling reptiles. Reptile abundance, species richness and diversity were highest where grazing intensity was low. Importantly, no species of reptile was more likely to occur at high grazing intensities. Legless lizards (Delma impar, D. inornata) were more likely to be detected in areas subject to moderate grazing intensity, whereas one species (Hemiergis talbingoensis) was less likely to be detected in areas subject to intense grazing and three species (Menetia greyii, Morethia boulengeri, and Lampropholis delicata) did not appear to be affected by grazing intensity. Our data indicate that to maximize reptile abundance, species richness, species diversity, and occurrence of several individual species of reptile, managers will need to subject different areas of the landscape to moderate and low grazing intensities and limit the occurrence and extent of high grazing

    The affordances of 3D and 4D digital technologies for computerized facial depiction

    Get PDF
    3D digital technologies have advanced rapidly over recent decades and they can now afford new ways of interacting with anatomical and cultural artefacts. Such technologies allow for interactive investigation of visible or non-observable surfaces, haptic generation of content and tactile experiences with digital and physical representations. These interactions and technical advances often facilitate the generation of new knowledge through interdisciplinary and sympathetic approaches. Scientific and public understanding of anatomy are often enhanced by clinical imaging technologies, 3D surface scanning techniques, 3D haptic modelling methods and 3D fabrication systems. These digital and haptic technologies are seen as non-invasive and allow scientists, artists and the public to become active investigators in the visualisation of, and interaction with, human anatomy, remains and histories. Face Lab is a Liverpool John Moores University research group that focuses on creative digital face research; specifically the further development of a 3D computerized craniofacial depiction system, utilizing 3D digital technologies in facial analysis and identification of human remains for forensic investigation, or historical figures for archaeological interpretation. This chapter explores the affordances of such interactions for the non-destructive production of craniofacial depiction, through a case-study based exploration of Face Lab workflow

    Microbial carcinogenic toxins and dietary anti-cancer protectants

    Get PDF

    Evidence-based Kernels: Fundamental Units of Behavioral Influence

    Get PDF
    This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior–influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of its components would render it inert. Existing evidence shows that a variety of kernels can influence behavior in context, and some evidence suggests that frequent use or sufficient use of some kernels may produce longer lasting behavioral shifts. The analysis of kernels could contribute to an empirically based theory of behavioral influence, augment existing prevention or treatment efforts, facilitate the dissemination of effective prevention and treatment practices, clarify the active ingredients in existing interventions, and contribute to efficiently developing interventions that are more effective. Kernels involve one or more of the following mechanisms of behavior influence: reinforcement, altering antecedents, changing verbal relational responding, or changing physiological states directly. The paper describes 52 of these kernels, and details practical, theoretical, and research implications, including calling for a national database of kernels that influence human behavior

    Challenges and trends in comparative higher education: an editorial

    No full text
    [Introduction] International comparative higher education research has proliferated since its institutionalization as an interdisciplinary field in the 1960s and 1970s (Jarausch 1985) and has gained special momentum in the 1990s (Teichler 1996). On the one hand, the benefits of comparative research approaches in international higher education have been repeatedly emphasized (Altbach and Kelly 1985; Teichler 1996; Rhoades 2001). These include, for example, increasing the capacity to generalize about a greater number of units under analysis, the capacity of a systematic comparison to illuminate the dynamics of a particular system better than a single-system study as well as highlighting knowledge gaps. On the other hand, methodological debates about comparing higher education internationally and how best to compare them emerged hand-in-hand with the field’s growth in popularity. Although the logic of international comparative research does not differ from research undertaken just within one country (Teichler 1996; Goedebuure and Van Vught 1996), some problems are posed in an especially complicated and intractable fashion (Hantrais 2009; Smelser 1976/2013), because of the focus on units that are dissimilar as well as similar (to be comparable). This poses specific challenges to international comparative research. [Continues, please see the article]nonPeerReviewe
    corecore