61 research outputs found

    Knowledge and Beliefs Associated with Environmental Health Literacy: A Case Study Focused on Toxic Metals Contamination of Well Water

    Get PDF
    Environmental health literacy (EHL) is developing as a framework that can inform educational interventions designed to facilitate individual and collective action to protect health, yet EHL measurement poses several challenges. While some studies have measured environmental health knowledge resulting from interventions, few have incorporated skills and self-efficacy. In this study, a process-focused EHL instrument was developed, using the Newest Vital Sign (NVS) health literacy instrument as a model and tailoring it for the context of private well contamination with toxic metals. Forty-seven (47) participants, including undergraduate students and residents of communities with contaminated well water, piloted a prototype EHL instrument alongside NVS. Results suggested a moderate degree of correlation between NVS and the EHL prototype, and significant differences in scores were observed between students and residents. Responses to a self-efficacy survey, tailored for drinking water contaminated with arsenic, revealed significant differences between students and residents on items related to cost and distance. In response to open-ended questions, participants identified a range of potential environmental contaminants in drinking water and deemed varied information sources as reliable. This study highlights differences in knowledge and self-efficacy among students and residents and raises questions about the adequacy of EHL assessments that mimic formal education approaches

    Integrated single- and two-photon light sheet microscopy using accelerating beams

    Get PDF
    The authors thank the UK Engineering and Physical Sciences Research Council (grant EP/J01771/X) and the European Union project FAMOS (FP7 ICT, contract no. 317744) for funding. P.P. acknowledges funding by the Estonian Research Council (grants PUTJD8 and PUT369).We demonstrate the first light sheet microscope using propagation invariant, accelerating Airy beams that operates both in single- and two-photon modes. The use of the Airy beam permits us to develop an ultra compact, high resolution light sheet system without beam scanning. In two-photon mode, an increase in the field of view over the use of a standard Gaussian beam by a factor of six is demonstrated. This implementation for light sheet microscopy opens up new possibilities across a wide range of biomedical applications, especially for the study of neuronal processes.Publisher PDFPeer reviewe

    A Plasmodium falciparum Histone Deacetylase Regulates Antigenic Variation and Gametocyte Conversion

    Get PDF
    SummaryThe asexual forms of the malaria parasite Plasmodium falciparum are adapted for chronic persistence in human red blood cells, continuously evading host immunity using epigenetically regulated antigenic variation of virulence-associated genes. Parasite survival on a population level also requires differentiation into sexual forms, an obligatory step for further human transmission. We reveal that the essential nuclear gene, P. falciparum histone deacetylase 2 (PfHda2), is a global silencer of virulence gene expression and controls the frequency of switching from the asexual cycle to sexual development. PfHda2 depletion leads to dysregulated expression of both virulence-associated var genes and PfAP2-g, a transcription factor controlling sexual conversion, and is accompanied by increases in gametocytogenesis. Mathematical modeling further indicates that PfHda2 has likely evolved to optimize the parasite’s infectious period by achieving low frequencies of virulence gene expression switching and sexual conversion. This common regulation of cellular transcriptional programs mechanistically links parasite transmissibility and virulence

    Higher gametocyte production and mosquito infectivity in chronic compared to incident Plasmodium falciparum infections.

    Get PDF
    Plasmodium falciparum gametocyte kinetics and infectivity may differ between chronic and incident infections. In the current study, we assess parasite kinetics and infectivity to mosquitoes among children (aged 5-10 years) from Burkina Faso with (a) incident infections following parasite clearance (n = 48) and (b) chronic asymptomatic infections (n = 60). In the incident infection cohort, 92% (44/48) of children develop symptoms within 35 days, compared to 23% (14/60) in the chronic cohort. All individuals with chronic infection carried gametocytes or developed them during follow-up, whereas only 35% (17/48) in the incident cohort produce gametocytes before becoming symptomatic and receiving treatment. Parasite multiplication rate (PMR) and the relative abundance of ap2-g and gexp-5 transcripts are positively associated with gametocyte production. Antibody responses are higher and PMR lower in chronic infections. The presence of symptoms and sexual stage immune responses are associated with reductions in gametocyte infectivity to mosquitoes. We observe that most incident infections require treatment before the density of mature gametocytes is sufficient to infect mosquitoes. In contrast, chronic, asymptomatic infections represent a significant source of mosquito infections. Our observations support the notion that malaria transmission reduction may be expedited by enhanced case management, involving both symptom-screening and infection detection
    corecore