10 research outputs found

    Americans’ Global Warming Beliefs and Attitudes

    Get PDF
    This report presents results from a national study of what Americans understand about how the climate system works, and the causes, impacts, and potential solutions to global warming. Among other findings, the study identifies a number of important gaps in public knowledge and common misconceptions about climate change. Educational levels: Graduate or professional, Undergraduate upper division, Undergraduate lower division, General public

    Mineral magnetism of dusty olivine:A credible recorder of pre-accretionary remanence

    Get PDF
    The magnetic properties of olivine-hosted Fe-Ni particles have been studied to assess the potential of “dusty olivine” to retain a pre-accretionary remanence in chondritic meteorites. Both body-centered (bcc) and face-centered cubic (fcc) Fe-Ni phases were formed by reduction of a terrestrial olivine precursor. The presence of Ni complicates the magnetic properties during heating and cooling due to the fcc-bcc martensitic transition. First-order reversal curve (FORC) diagrams contain a central ridge with a broad coercivity distribution extending to 600 mT, attributed to non-interacting single-domain (SD) particles, and a “butterfly” structure extending to 250 mT, attributed to single-vortex (SV) states. SD and SV states were imaged directly using electron holography. The location of the SD/SV boundary is broadly consistent with theoretical predictions. A method to measure the volume of individual SD particles using electron holography is presented. Combining the volume information with constraints on coercivity, we calculate the thermal relaxation characteristics of the particles and demonstrate that the high-coercivity component of remanance would remain stable for 4.6 Ga, even at temperatures approaching the Curie temperature of pure Fe. The high coercivity of the particles, together with the chemical protection offered by the surrounding olivine, is likely to make them resistant to shock remagnetization, isothermal remagnetization and terrestrial weathering, making dusty olivine a credible recorder of pre-accretionary magnetic fields

    Do Americans Understand That Global Warming Is Harmful to Human Health? Evidence From a National Survey

    Get PDF
    Background: Global warming has significant negative consequences for human health, with some groups at greater risk than others. The extent to which the public is aware of these risks is unclear; the limited extant research has yielded discrepant findings. Objectives: This paper describes Americans' awareness of the health effects of global warming, levels of support for government funding and action on the issue, and trust in information sources. We also investigate the discrepancy in previous research findings between assessments based on open- versus closed-ended questions. Methods: A nationally representative survey of US adults (N = 1275) was conducted online in October 2014. Measures included general attitudes and beliefs about global warming, affective assessment of health effects, vulnerable populations and specific health conditions (open- and closed-ended), perceived risk, trust in sources, and support for government response. Findings: Most respondents (61%) reported that, before taking the survey, they had given little or no thought to how global warming might affect people's health. In response to a closed-ended question, many respondents (64%) indicated global warming is harmful to health, yet in response to an open-ended question, few (27%) accurately named one or more specific type of harm. In response to a closed-ended question, 33% indicated some groups are more affected than others, yet on an open-ended question only 25% were able to identify any disproportionately affected populations. Perhaps not surprising given these findings, respondents demonstrated only limited support for a government response: less than 50% of respondents said government should be doing more to protect against health harms from global warming, and about 33% supported increased funding to public health agencies for this purpose. Respondents said their primary care physician is their most trusted source of information on this topic, followed by the Centers for Disease Control and Prevention, the World Health Organization, and their local public health department. Conclusions: Most Americans report a general sense that global warming can be harmful to health, but relatively few understand the types of harm it causes or who is most likely to be affected. Perhaps as a result, there is only moderate support for an expanded public health response. Primary care physicians and public health officials appear well positioned to educate the public about the health relevance of climate chang

    Deficits in neurite density underlie white matter structure abnormalities in first-episode psychosis

    Get PDF
    Background: Structural abnormalities across multiple white matter tracts are recognised in people with early psychosis, consistent with dysconnectivity as a neuropathological account of symptom expression. We applied advanced neuroimaging techniques to characterise microstructural white matter abnormalities for a deeper understanding of the developmental aetiology of psychosis. Methods: Thirty-five first-episode psychosis patients, and 19 healthy controls, participated in a quantitative neuroimaging study using Neurite Orientation Dispersion and Density Imaging (NODDI), a multi-shell diffusion-weighted MRI technique that distinguishes white matter fibre arrangement and geometry from changes in neurite density. Fractional anisotropy (FA) and mean diffusivity images were also derived. Tract-based spatial statistics compared white matter structure between patients and controls and tested associations with age, symptom severity and medication. Results: Patients with first-episode psychosis had lower regional FA in multiple commissural, corticospinal, and association tracts. These abnormalities predominantly colocalized with regions of reduced neurite density, rather than aberrant fibre bundle arrangement (orientation dispersion index). There was no direct relationship with active symptomatology. FA decreased and orientation dispersion index increased with age in patients, but not controls, suggesting accelerated effects of white matter geometry change. Conclusions: Deficits in neurite density appear fundamental to abnormalities in white matter integrity in early psychosis. In the first application of NODDI in psychosis, we found that processes compromising axonal fibre number, density, and myelination, rather than processes leading to spatial disruption of fibre organisation, are implicated in the aetiology of the disorder. This accords with a neurodevelopmental origin of aberrant brain-wide structural connectivity predisposing individuals to psychosis

    A novel retinoblastoma therapy from genomic and epigenetic analyses

    Get PDF
    Retinoblastoma is an aggressive childhood cancer of the developing retina that is initiated by the biallelic loss of the RB1 gene. To identify the mutations that cooperate with RB1 loss, we performed whole-genome sequencing of retinoblastomas. The overall mutational rate was very low; RB1 was the only known cancer gene mutated. We then evaluated RB1’s role in genome stability and considered nongenetic mechanisms of cancer pathway deregulation. Here we show that the retinoblastoma genome is stable, but multiple cancer pathways can be epigenetically deregulated. For example, the proto-oncogene SYK is upregulated in retinoblastoma and is required for tumor cell survival. Targeting SYK with a small-molecule inhibitor induced retinoblastoma tumor cell death in vitro and in vivo. Thus, RB1 inactivation may allow preneoplastic cells to acquire multiple hallmarks of cancer through epigenetic mechanisms, resulting directly or indirectly from RB1 loss. These data provide novel targets for chemotherapeutic interventions of retinoblastoma

    La calidad de la educaciĂłn como parte del problema: educaciĂłn escolar y desigualdad en Chile

    No full text
    corecore