111 research outputs found

    Prenatal exposure to pyrethroid pesticides and childhood behavior and executive functioning

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    Several previous studies of pyrethroid biomarkers and behavior have reported associations between concurrent pyrethroid levels and adverse behavioral problems in children. One geospatial study reported associations between prenatal exposure to pyrethroids and autism. However, the association between prenatal pyrethroid biomarkers and childhood behavior is unknown. The Mount Sinai Children's Environmental Health Center is a prospective birth cohort with urinary pyrethroid biomarkers during pregnancy and behavioral measurements at 4, 6, and 7–9 years of age. Primiparous women were enrolled between 1998 and 2002. 162 mother/child pairs with complete exposure and behavioral outcomes data were used to investigate associations between detectable levels of prenatal pyrethroid metabolites and scores on the Behavioral Assessment System for Children and the Behavior Rating Inventory of Executive Function. Overall, detection frequencies of pyrethroid metabolites were low (<30%). In longitudinal mixed models, detectable levels of 3-PBA during pregnancy were associated with worse Internalizing (β −4.50, 95% CI −8.05, −0.95), Depression (β −3.21, 95% CI −6.38, −0.05), Somatization (β −3.22, 95% CI −6.38, −0.06), Behavioral Regulation (β −3.59, 95% CI −6.97, −0.21), Emotional Control (β −3.35, 95% CI −6.58, −0.12), Shifting (β −3.42, 95% CI −6.73, −0.11), and Monitoring (β −4.08, 95% CI −7.07, −1.08) scales. Detectable levels of cis-DCCA were associated with worse Externalizing (β −4.74, 95% CI −9.37, −0.10), Conduct Problems (β −5.35, 95% CI −9.90, −0.81), Behavioral Regulation (β −6.42, 95% CI −11.39, −1.45), and Inhibitory Control (β −7.20, 95% CI −12.00, −2.39). Although detection frequencies of pyrethroid metabolites were low, we found suggestive evidence that prenatal exposure to 3-PBA and cis-DCCA may be associated with a variety of behavioral and executive functioning deficits

    Prenatal exposure to organophosphates, paraoxonase 1, and cognitive development in childhood

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    Background: Prenatal exposure to organophosphate pesticides has been shown to negatively affect child neurobehavioral development. Paraoxonase 1 (PON1) is a key enzyme in the metabolism of organophosphates. Objective: We examined the relationship between biomarkers of organophosphate exposure, PON1, and cognitive development at ages 12 and 24 months and 6-9 years. Methods: The Mount Sinai Children's Environmental Health Study enrolled a multiethnic prenatal population in New York City between 1998 and 2002 (n = 404). Third-trimester maternal urine samples were collected and analyzed for organophosphate metabolites (n = 360). Prenatal maternal blood was analyzed for PON1 activity and genotype. Children returned for neurodevelopment assessments ages 12 months (n = 200), 24 months (n = 276), and 6-9 (n = 169) years of age. Results: Prenatal total dialkylphosphate metabolite level was associated with a decrement in mental development at 12 months among blacks and Hispanics. These associations appeared to be enhanced among children of mothers who carried the PON1 Q192R QR/RR genotype. In later childhood, increasing prenatal total dialkyl- and dimethylphosphate metabolites were associated with decrements in perceptual reasoning in the maternal PON1 Q192R QQ genotype, which imparts slow catalytic activity for chlorpyrifos oxon, with a monotonic trend consistent with greater decrements with increasing prenatal exposure. Conclusion: Our findings suggest that prenatal exposure to organophosphates is negatively associated with cognitive development, particularly perceptual reasoning, with evidence of effects beginning at 12 months and continuing through early childhood. PON1 may be an important susceptibility factor for these deleterious effects

    Imaging Spectroscopy of a White-Light Solar Flare

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    We report observations of a white-light solar flare (SOL2010-06-12T00:57, M2.0) observed by the Helioseismic Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). The HMI data give us the first space-based high-resolution imaging spectroscopy of a white-light flare, including continuum, Doppler, and magnetic signatures for the photospheric FeI line at 6173.34{\AA} and its neighboring continuum. In the impulsive phase of the flare, a bright white-light kernel appears in each of the two magnetic footpoints. When the flare occurred, the spectral coverage of the HMI filtergrams (six equidistant samples spanning \pm172m{\AA} around nominal line center) encompassed the line core and the blue continuum sufficiently far from the core to eliminate significant Doppler crosstalk in the latter, which is otherwise a possibility for the extreme conditions in a white-light flare. RHESSI obtained complete hard X-ray and \Upsilon-ray spectra (this was the first \Upsilon-ray flare of Cycle 24). The FeI line appears to be shifted to the blue during the flare but does not go into emission; the contrast is nearly constant across the line profile. We did not detect a seismic wave from this event. The HMI data suggest stepwise changes of the line-of-sight magnetic field in the white-light footpoints.Comment: 14 pages, 7 figures, Accepted by Solar Physic

    Prenatal exposure to organophosphorus pesticides and childhood neurodevelopmental phenotypes

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    Prenatal exposure to organophosphorus pesticides (OPs) has been associated with different neurodevelopmental outcomes across different cohorts. A phenotypic approach may address some of these differences by incorporating information across scales and accounting for the complex correlational structure of neurodevelopmental outcomes. Additionally, Bayesian hierarchical modeling can account for confounding by collinear co-exposures. We use this framework to examine associations between prenatal exposure to OPs and behavior, executive functioning, and IQ assessed at age 6–9 years in a cohort of 404 mother/infant pairs recruited during pregnancy. We derived phenotypes of neurodevelopment with a factor analysis, and estimated associations between OP metabolites and these phenotypes in Bayesian hierarchical models for exposure mixtures. We report seven factors: 1) Impulsivity and Externalizing, 2) Executive Functioning, 3) Internalizing, 4) Perceptual Reasoning, 5) Adaptability, 6) Processing Speed, and 7) Verbal Intelligence. These, along with the Working Memory Index, were standardized and scaled so that positive values reflected positive attributes and negative values represented adverse outcomes. Standardized dimethylphosphate metabolites were negatively associated with Internalizing factor scores (β^ − 0.13, 95% CI − 0.26, 0.00) but positively associated with Executive Functioning factor scores (β^ 0.18, 95% CI 0.04, 0.31). Standardized diethylphosphate metabolites were negatively associated with the Working Memory Index (β^ − 0.17, 95% CI − 0.33, − 0.03). Associations with factor scores were generally stronger and more precise than associations with individual instrument-specific items. Factor analysis of outcomes may provide some advantages in etiological studies of childhood neurodevelopment by incorporating information across scales to reduce dimensionality and improve precision

    Global Properties of Solar Flares

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    The Galactic Environment of the Sun: Interstellar Material Inside and Outside of the Heliosphere

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    Search for long-lived neutral particles in pp collisions at s√=13 TeV that decay into displaced hadronic jets in the ATLAS calorimeter

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    This paper describes a search for pairs of neutral, long-lived particles decaying in the ATLAS calorimeter. Long-lived particles occur in many extensions to the Standard Model and may elude searches for new promptly decaying particles. The analysis considers neutral, long-lived scalars with masses between 5 and 400 GeV, produced from decays of heavy bosons with masses between 125 and 1000 GeV, where the long-lived scalars decay into Standard Model fermions. The analysis uses either 10.8 fb−1 or 33.0 fb−1 of data (depending on the trigger) recorded in 2016 at the LHC with the ATLAS detector in proton–proton collisions at a centre-of-mass energy of 13 TeV. No significant excess is observed, and limits are reported on the production cross section times branching ratio as a function of the proper decay length of the long-lived particles

    Statistical comparison of algorithms

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    A "reference" algorithm or instrument and its various "distortions" are considered, where the distortions carry some valid information about the reference. The objective is to combine data from the reference and the distortions together in some manner in order to extract information from both the reference, as well as the distortions, and produce improved inference about the true reference algorithm. This is illustrated in terms of m precipitation radars and semiparametric estimation of the reference distribution and the distortion parameters
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