79 research outputs found
Sensitivity of desert dust emissions to model horizontal grid spacing during the Bodélé Dust Experiment 2005
The impact of model horizontal grid spacing on meteorology and dust emissions in the Bodélé depression was investigated during the well-documented period of the Bodélé Dust Experiment 2005 (BoDEx 2005). Five horizontal grid spacing ranging from 100 km to 5 km were tested. The main conclusion of these sensitivity tests is that the meteorology of the Bodélé depression is quite insensitive to model horizontal grid spacing below 50 km in agreement with Todd et al.'s (2008b) results. Below 50 km, dust emissions also appear relatively insensitive to model mesh size, the influence of model horizontal grid spacing on dust emissions tending towards an asymptotic behavior as model mesh size is reduced
Bis(3-acetyl-6-methyl-2-oxo-2H-pyran-4-olato)bisÂ(dimethyl sulfoxide)nickel(II)
In the title compound, [Ni(C8H7O4)2{(CH3)2SO}2], the NiII atom is located on a crystallographic centre of symmetry and has a distorted octaÂhedral coordination geometry of type MO6. The bidentate dehydroÂacetic acid (DHA) ligands occupy the equatorial plane of the complex in a trans configuration, and the dimethyl sulfoxide (DMSO) ligands are weakly coordinated through their O atoms in the axial positions
2,4-Dichloro-6-({2-[(3,5-dichloro-2-hyÂdroxyÂbenzylÂidene)amino]ÂethÂyl}iminoÂmethÂyl)phenol
The title molÂecule, C16H12Cl4N2O2, lies about an inversion center. The symmetry-unique part of the molÂecule contains an intraÂmolecular OâHâŻN hydrogen bond. In the crystal, molÂecules are arranged in corrugated layers parallel to (-101). Weak ÏâÏ stacking interÂactions, with a centroidâcentroid diatance of 3.7923â
(13)â
Ă
, are present
2-[N-(4-{4-[(2-HyÂdroxy-5-methÂoxyÂbenzylÂidene)amino]ÂbenzÂyl}phenÂyl)carboximidoÂyl]-4-methÂoxyÂphenol
In the title Schiff base, C29H26N2O4, the complete molecule is generated by a crystallographic twofold axis and is V-shaped. The planes of the benzene rings of the central diphenylÂmethane unit make a dihedral angle of 78.11â
(4)° while adjacent benzene and 5-methÂoxyÂsalicylÂidene rings are twisted with respect to each other by a dihedral angle of 11.84â
(8)°. The Schiff base is in the enolâimino form and an intraÂmolecular OâHâŻN hydrogen bond is observed
Research response to coronavirus disease 2019 needed better coordination and collaboration: a living mapping of registered trials
Objectives: Researchers worldwide are actively engaging in research activities to search for preventive and therapeutic interventions against coronavirus disease 2019 (COVID-19). Our aim was to describe the planning of randomized controlled trials (RCTs) in terms of timing related to the course of the COVID-19 epidemic and research question evaluated. Study Design and Setting: We performed a living mapping of RCTs registered in the WHO International Clinical Trials Registry Platform. We systematically search the platform every week for all RCTs evaluating preventive interventions and treatments for COVID-19 and created a publicly available interactive mapping tool at https://covid-nma.com to visualize all trials registered. Results: By August 12, 2020, 1,568 trials for COVID-19 were registered worldwide. Overall, the median ([Q1âQ3]; range) delay between the first case recorded in each country and the first RCT registered was 47 days ([33â67]; 15â163). For the 9 countries with the highest number of trials registered, most trials were registered after the peak of the epidemic (from 100% trials in Italy to 38% in the United States). Most trials evaluated treatments (1,333 trials; 85%); only 223 (14%) evaluated preventive strategies and 12 postacute period intervention. A total of 254 trials were planned to assess different regimens of hydroxychloroquine with an expected sample size of 110,883 patients. Conclusion: This living mapping analysis showed that COVID-19 trials have relatively small sample size with certain redundancy in research questions. Most trials were registered when the first peak of the pandemic has passed
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