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We have deduced the emission probability of the 447-keV γ ray from the ϵ+β+ decay of Ceg137 (9.0 h) relative to that of the 254-keV γ ray from the Cem137 (34.4 h) decay in transient equilibrium. The time-dependent factor in transient equilibrium was applied following the Bateman equation for a radioactive decay chain. The isotope was produced via the La139(p,3n)Cem,g137 reaction by bombarding natLa with a proton beam from the 88-in. cyclotron at Lawrence Berkeley National Laboratory. γ-ray intensities were measured using an HPGe detector. The emission probability for the 447-keV γ ray deduced in this work is 1.21(3) (that is 1.21 ± 0.03) per hundred parent decays, which differs significantly from an earlier published value of 2.24(10). We identify the source of this discrepancy to be an incorrect use of the time-dependent factor. Additionally, we have deduced the emission probability of the 504-keV γ ray from the decay of Yg85 (2.68 h) relative to that of the 232-keV γ ray from the Srm85 (1.127 h) decay in transient equilibrium. The isotope was produced via the Sr86(p,2n)Yg85 reaction by bombarding SrCO386 with a proton beam at the same facility. The study confirms the assumption of the time-dependent correction for recommending the emission probability of the 504-keV γ ray in the literature. Our work highlights the importance of explicit description by authors of any time-dependent correction they have made when reporting γ-ray intensities for nuclides in transient equilibrium. The need and significance of accurate and precise decay data of Ceg137 and Yg85 in basic science and medicine is briefly outlined.

Peroxynitrates are responsible for global scale transport of reactive nitrogen. Recent laboratory observations suggest that they may also play an important role in delivery of nutrients to plant canopies. We measured eddy covariance fluxes of total peroxynitrates (ΣPNs) and three individual peroxynitrates (APNs ≡ PAN + PPN + MPAN) over a ponderosa pine forest during the Biosphere Effects on AeRosols and Photochemistry EXperiment 2009 (BEARPEX 2009). Concentrations of these species were also measured at multiple heights above and within the canopy. While the above-canopy daytime concentrations are nearly identical for ΣPNs and APNs, we observed the downward flux of ΣPNs to be 30–60% slower than the flux of APNs. The vertical concentration gradients of ΣPNs and APNs vary with time of day and exhibit different temperature dependencies. These differences can be explained by the production of peroxynitrates other than PAN, PPN, and MPAN within the canopy (presumably as a consequence of biogenic VOC emissions) and upward fluxes of these PN species. The impact of this implied peroxynitrate flux on the interpretation of NOx fluxes and ecosystem N exchange is discussed.

Using measurements from the NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) experiment, we show that methyl peroxy nitrate (CH3O2NO2) is present in concentrations of ~5–15 pptv in the springtime arctic upper troposphere. We investigate the regional and global effects of CH3O2NO2 by including its chemistry in the GEOS-Chem 3-D global chemical transport model. We find that at temperatures below 240 K inclusion of CH3O2NO2 chemistry results in decreases of up to ~20 % in NOx, ~20 % in N2O5, ~5 % in HNO3, ~2 % in ozone, and increases in methyl hydrogen peroxide of up to ~14 %. Larger changes are observed in biomass burning plumes lofted to high altitude. Additionally, by sequestering NOx at low temperatures, CH3O2NO2 decreases the cycling of HO2 to OH, resulting in a larger upper tropospheric HO2 to OH ratio. These results may impact some estimates of lightning NOx sources as well as help explain differences between models and measurements of upper tropospheric composition.

Background: Sleep problems are regularly reported in people with intellectual disabilities. Recent years have seen a substantial increase in studies comparing sleep in people with intellectual disabilities to control participants, with an increase in the use of validated, objective measures. Emerging patterns of differences in sleep time and sleep quality warrant pooled investigation. Methods: A systematic search was conducted across three databases (Ovid Embase, PsycInfo and Medline) and returned all papers comparing sleep in people with intellectual disabilities to a control group, published since the last meta‐analysis on the topic. A quality framework was employed to rate the risk of bias across studies. Separate meta‐analyses of sleep duration and sleep quality were conducted. Subgrouping compared findings for those studies with participants with genetic syndromes or neurodevelopmental conditions and those with heterogeneous intellectual disability. Results: Thirteen new papers were identified and combined with those from the previous meta‐analysis to provide 34 papers in total. Quality of studies was generally rated highly, though sampling provided risk of bias and adaptive functioning was rarely measured. People with intellectual disability associated with genetic syndromes or neurodevelopmental conditions sleep for shorter time periods (standardised mean difference =.26) and experience worse sleep quality (standardised mean difference =.68) than their peers. People with intellectual disability of heterogeneous origin show no difference in sleep time but have poorer sleep quality. There was some evidence that age moderated these effects. Conclusions: People with intellectual disability have poorer sleep than those without. Subtle patterns suggest that aetiology of intellectual disability moderates the topography of these difficulties, with further work needed to differentiate common and distinct mechanisms across groups. [ABSTRACT FROM AUTHOR]

Berry, oomycete, pathogenicity, Peronosporales Keywords: berry; oomycete; pathogenicity; Peronosporales EN berry oomycete pathogenicity Peronosporales 1 3 3 09/28/23 20230701 NES 230701 Twenty-two root samples from raspberry plants exhibiting symptoms consistent with I Phytophthora i infection, i.e. cane wilt, chlorotic leaves, and blackened roots, were collected from two farms in Perthshire, Scotland, in November 2021 (Fig. [Extracted from the article]