654 research outputs found

    Bis(benzimidazolium) naphthalene-1,5-disulfonate trihydrate

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    The title compound, 2C7H7N2 +·C10H6O6S2 2−·3H2O, consists of two crystallographically independent benzimidazolium cations, two independent naphthalene-1,5-disulfonate dianions (both generated by inversion) and three water mol­ecules. These components construct an infinite three-dimensional framework in the crystal structure via O—H⋯O and N—H⋯O hydrogen bonds

    Radial Angular Momentum Transfer and Magnetic Barrier for Short-Type Gamma-Ray Burst Central Engine Activity

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    Soft extended emission (EE) following initial hard spikes up to 100 seconds was observed with {\em Swift}/BAT for about half of short-type gamma-ray bursts (SGRBs). This challenges the conversional central engine models of SGRBs, i.e., compact star merger models. In the framework of the black hole-neutron star merger models, we study the roles of the radial angular momentum transfer in the disk and the magnetic barrier around the black hole for the activity of SGRB central engines. We show that the radial angular momentum transfer may significantly prolong the lifetime of the accretion process and multiple episodes may be switched by the magnetic barrier. Our numerical calculations based on the models of the neutrino-dominated accretion flows suggest that the disk mass is critical for producing the observed EE. In case of the mass being 0.8M\sim 0.8M_{\odot}, our model can reproduce the observed timescale and luminosity of both the main and EE episodes in a reasonable parameter set. The predicted luminosity of the EE component is lower than the observed EE with about one order of magnitude and the timescale is shorter than 20 seconds if the disk mass being 0.2M\sim 0.2M_{\odot}. {\em Swift}/BAT-like instruments may be not sensitive enough to detect the EE component in this case. We argue that the EE component would be a probe for merger process and disk formation for compact star mergers.Comment: 9 pages, 3 figures, accepted for publication in Ap

    Poly[(acetato-κ2 O,O′)aqua­(μ4-1H-benzimidazole-5,6-dicarboxyl­ato-κ5 N 3:O 5,O 5′:O 5,O 6:O 6′)praseodymium(III)]

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    In the title complex, [Pr(C9H4N2O4)(C2H3O2)(H2O)]n, the PrIII ion is coordinated by five O atoms and one N atom from four benzimidazole-5,6-dicarboxyl­ate ligands, two O atoms from an acetate ligand and one water mol­ecule, giving a tricapped trigonal-prismatic geometry. The benzimidazole-5,6-dicarboxyl­ate and acetate ligands connect the PrIII ions, forming a layer in the ac plane; the layers are further linked by N—H⋯O and O—H⋯O hydrogen bonding and π–π stacking inter­actions between neighboring pyridine rings [the centroid–centroid distance is 3.467 (1) Å], assembling a three-dimensional supra­molecular network. The acetate methyl group is disordered over two positions with site-occupancy factors of 0.75 and 0.25

    (9H-Carbazol-9-ylmeth­yl)diethyl­amine

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    The asymmetric unit of the title compound, C17H20N2, contains two mol­ecules, whose bond lengths and angles differ only slightly. In the crystal, neighbouring mol­ecules form pillar structures via edge-to-face π–π stacking inter­actions [edge-to-face distances = 3.538 (3) and 3.496 (3)Å]

    Influence of lifestyle on suboptimal health: Insights from a national cross-sectional survey in China

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    Background: Suboptimal health status (SHS) is a non-clinical or pre-disease state between optimal/ideal health and disease. While its etiology remains unclear, lifestyle is considered one of the most important risk factors. We aimed to examine the effects of lifestyles on SHS through a nationwide survey in China. Methods: We conducted a cross-sectional survey in 148 cities across China between 20 June and 31 August 2022, on 30 505 participants from rural and urban communities gathered through stratified quota sampling. We measured SHS with the Short-Form Suboptimal Health Status Questionnaire (SHSQ-SF). We gathered information on participants\u27 lifestyles (ie, smoking, alcohol consumption, breakfast habits, weekly food delivery frequency, intermittent fasting, sleep duration and physical activities) through face-to-face interview. We determined the relationship between lifestyle and SHS logistic regression analysis by based on odds ratios (ORs) and 95% confidence intervals (CIs). Results: We included 22 897 participants (female: 13 056, male: 9841), 12 108 (52.88%) of whom reported exposure to SHS. After adjusting for demographic characteristics, individuals who currently smoked (OR = 1.165; 95% CI = 1.058-1.283) and those who drank alcohol (OR = 1.483; 95% CI = 1.377.1.596) were at a higher risk of SHS than those who have never done either. In a dose-response way, takeaway food consumption was associated with a higher risk of SHS, while increased frequency of breakfast and mild-intensity exercise conversely reduced said risk. Individuals with shorter sleep duration had a higher risk of SHS when compared to those who slept for more than seven hours per day. Conclusions: We observed a relatively high prevalence of SHS across China, highlighting the importance of lifestyle in health promotion. Specifically, adopting healthy dietary habits, engaging in regular physical activity, and ensuring high-quality sleep are key in preventing SHS. Registration: Chinese Clinical Trial Registry (ChiCTR2200061046)
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