3,663 research outputs found

    Is cannabis use a contributory cause of psychosis?

    Get PDF
    Objective: To assess whether cannabis use in adolescence and young adulthood is a contributory cause of schizophreniform psychosis in that it may precipitate psychosis in vulnerable individuals. Method: We reviewed longitudinal studies of adolescents and young adults that examined the relations between self-reported cannabis use and the risk of diagnosis with a psychosis or of reporting psychotic symptoms. We also reviewed studies that controlled for potential confounders, such as other forms of drug use and personal characteristics that predict an increased risk of psychosis. We assessed evidence for the biological plausibility of a contributory causal relation. Results: Evidence from 6 longitudinal studies in 5 countries shows that regular cannabis use predicts an increased risk of a schizophrenia diagnosis or of reporting symptoms of psychosis. These relations persisted after controlling for confounding variables, such as personal characteristics and other drug use. The relation did not seem to be a result of cannabis use to self-medicate symptoms of psychosis. A contributory causal relation is biologically plausible because psychotic disorders involve disturbances in the dopamine neurotransmitter systems with which the cannabinoid system interacts, as demonstrated by animal studies and one human provocation study. Conclusion: It is most plausible that cannabis use precipitates schizophrenia in individuals who are vulnerable because of a personal or family history of schizophrenia

    Electron multiplication CCD detector technology advancement for the WFIRST-AFTA coronagraph

    Get PDF
    The WFIRST-AFTA (Wide Field InfraRed Survey Telescope-Astrophysics Focused Telescope Asset) is a NASA space observatory. It will host two major astronomical instruments: a wide-field imager (WFI) to search for dark energy and carry out wide field near infrared (NIR) surveys, and a coronagraph instrument (CGI) to image and spectrally characterize extrasolar planets. In this paper, we discuss the work that has been carried out at JPL in advancing Electron Multiplying CCD (EMCCD) technology to higher flight maturity, with the goal of reaching a NASA technology readiness level of 6 (TRL-6) by early-to-mid 2016. The EMCCD has been baselined for both the coronagraph's imager and integral field spectrograph (IFS) based on its sub-electron noise performance at extremely low flux levels - the regime where the AFTA CGI will operate. We present results from a study that fully characterizes the beginning of life performance of the EMCCD. We also discuss, and present initial results from, a recent radiation test campaign that was designed and carried out to mimic the conditions of the WFIRST-AFTA space environment in an L2 orbit, where we sought to assess the sensor's end of life performance, particularly degradation of its charge transfer efficiency, in addition to other parameters such as dark current, electron multiplication gain, clock induced charge and read noise

    Novel polymorphisms influencing transcription of the human CHRM2 gene in airway smooth muscle

    Get PDF
    Muscarinic receptors are a functionally important family of G-protein-coupled receptors. Using a combination of rapid amplification of 5′ cDNA ends and reporter gene assays, we characterized the 5′ untranslated region of the CHRM2 gene as expressed in human airway smooth muscle (HASM) cells. A splice site is present 46 bp upstream from the ATG start codon. Five exons with alternative splicing patterns are present upstream of this splice site, separated by introns ranging from 87 bp to > 145 kb. There is evidence for the gene being under the control of a TATA-less promoter with Sp1, GATA, and activator protein-2 binding sites. Multiple transcription start sites (TSSs) were identified. We identified a novel 0.5-kb hypervariable region located 648 bp upstream of the most 5′ TSS, a multiallelic (CA) tandem repeat 96 bp downstream of the most 5′ TSS, and a common C→A SNP located 136 bp upstream of the most 5′ TSS. Functional studies in primary HASM cells and the BEAS-2B cell line demonstrated highest promoter activity to be upstream of the most 3′ TSS, with potential repressor elements operating in a cell type-dependent manner, located upstream of the most 5′ TSS. We present functional data to show that the CA repeat may influence the transcription of the gene in HASM and BEAS-2B cells.peer-reviewe

    Evaluation of a workplace suicide prevention program in the Australian manufacturing industry : protocol for a cluster-randomised trial of MATES in manufacturing

    Get PDF
    Males are at higher risk of death by suicide than females in Australia, and among men, blue-collar males are at higher risk compared to other working males. In response, MATES in Construction developed a workplace suicide prevention program for the construction sector in 2007 that has been widely implemented in Australia. In the current project, this program is being adapted and trialled in the manufacturing sector. The common aims of MATES programs are to improve suicide prevention literacy, help-seeking intentions, and helping behaviours. The program will be evaluated using a cluster randomised-controlled trial design with waitlist controls across up to 12 manufacturing worksites in Australia. We hypothesise that after 8 months of the MATES in Manufacturing program, there will be significantly greater improvements in help-seeking intentions (primary outcome) compared to waitlist controls. The project is led by Deakin University in collaboration with the University of Melbourne, and in partnership with MATES in Construction and a joint labour-management Steering Group. Trial registration: The trial was registered retrospectively with the Australian New Zealand Clinical Trials Registry on 25 January 2022 (ACTRN12622000122752)

    Upgrade of the Glasgow photon tagging spectrometer for Mainz MAMI-C

    Full text link
    The Glasgow photon tagging spectrometer at Mainz has been upgraded so that it can be used with the 1500 MeV electron beam now available from the Mainz microtron MAMI-C. The changes made and the resulting properties of the spectrometer are discussed.Comment: 20 pages, 12 figure

    Empowerment or Engagement? Digital Health Technologies for Mental Healthcare

    Get PDF
    We argue that while digital health technologies (e.g. artificial intelligence, smartphones, and virtual reality) present significant opportunities for improving the delivery of healthcare, key concepts that are used to evaluate and understand their impact can obscure significant ethical issues related to patient engagement and experience. Specifically, we focus on the concept of empowerment and ask whether it is adequate for addressing some significant ethical concerns that relate to digital health technologies for mental healthcare. We frame these concerns using five key ethical principles for AI ethics (i.e. autonomy, beneficence, non-maleficence, justice, and explicability), which have their roots in the bioethical literature, in order to critically evaluate the role that digital health technologies will have in the future of digital healthcare

    Technology advancement of the CCD201-20 EMCCD for the WFIRST coronagraph instrument: sensor characterization and radiation damage

    Get PDF
    The Wide Field InfraRed Survey Telescope-Astrophysics Focused Telescope Asset (WFIRST-AFTA) mission is a 2.4-m class space telescope that will be used across a swath of astrophysical research domains. JPL will provide a high-contrast imaging coronagraph instrument—one of two major astronomical instruments. In order to achieve the low noise performance required to detect planets under extremely low flux conditions, the electron multiplying charge-coupled device (EMCCD) has been baselined for both of the coronagraph’s sensors—the imaging camera and integral field spectrograph. JPL has established an EMCCD test laboratory in order to advance EMCCD maturity to technology readiness level-6. This plan incorporates full sensor characterization, including read noise, dark current, and clock-induced charge. In addition, by considering the unique challenges of the WFIRST space environment, degradation to the sensor’s charge transfer efficiency will be assessed, as a result of damage from high-energy particles such as protons, electrons, and cosmic rays. Science-grade CCD201-20 EMCCDs have been irradiated to a proton fluence that reflects the projected WFIRST orbit. Performance degradation due to radiation displacement damage is reported, which is the first such study for a CCD201-20 that replicates the WFIRST conditions. In addition, techniques intended to identify and mitigate radiation-induced electron trapping, such as trap pumping, custom clocking, and thermal cycling, are discussed

    First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV

    Full text link
    A direct measurement of the helicity dependence of the total photoabsorption cross section on the proton was carried out at MAMI (Mainz) in the energy range 200 < E_gamma < 800 MeV. The experiment used a 4π\pi detection system, a circularly polarized tagged photon beam and a frozen spin target. The contributions to the Gerasimov-Drell-Hearn sum rule and to the forward spin polarizability γ0\gamma_0 determined from the data are 226 \pm 5 (stat)\pm 12(sys) \mu b and -187 \pm 8 (stat)\pm 10(sys)10^{-6} fm^4, respectively, for 200 < E_\gamma < 800 MeV.Comment: 6 pages, 3 figures, 3 table

    The helicity amplitudes A1/2_{1/2} and A3/2_{3/2} for the D13(1520)_{13}(1520) resonance obtained from the γ⃗p⃗→pπ0\vec{\gamma} \vec{p} \to p \pi^0 reaction}

    Full text link
    The helicity dependence of the γ⃗p⃗→pπ0\vec{\gamma} \vec{p} \to p \pi^0 reaction has been measured for the first time in the photon energy range from 550 to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4π\pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. These data are predominantly sensitive to the D13(1520)D_{13}(1520) resonance and are used to determine its parameters.Comment: 5 pages, 4 figure

    Eating Paradise: Food as Coloniality and Leisure

    Get PDF
    Sandals Resorts’ Gourmet Discovery Dining programme continues the company’s practice of marketing difference by combining tourism with the commodification of food from non-Western cultures (Dodman and Rhiney 2008). The article draws on bell hooks’ (1992) concept of ‘eating the other’ and the analysis undertakes an interdisciplinary approach that combines visual analysis with Anibal Quijano’s (2007) concept of modernity/coloniality. The discussion explores the trends of global multiculturalism that have been adopted by Sandals in a hybridized cut and mix approach to selling a packaged ideal of the Caribbean. The visual techniques devised to create a culinary holiday package are overlaid onto a manufactured and homogenised or McDonaldized (Ritzer and Liska 1997) Caribbean that provides insight into the way in which global neoliberal multiculturalism is framed by ongoing colonial relations after formal colonial rule has ended in the Caribbean region
    • …
    corecore