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141.
Large-scale evacuations are a recurring theme on news channels, whether in response to major natural or manmade disasters. The role of warning dissemination is a key part in the success of such large-scale evacuations and its inadequacy in certain cases has been a ‘primary contribution to deaths and injuries’ (Hayden et al., 2007). Along with technology-driven ‘official warning channels’ (e.g. sirens, mass media), the role of unofficial channel (e.g. neighbours, personal contacts, volunteer wardens) has proven to be significant in warning the public of the need to evacuate. Although post-evacuation studies identify the behaviours of evacuees as disseminators of the warning message, there has not been a detailed study that quantifies the effects of such behaviour on the warning message dissemination. This paper develops an Agent-Based Simulation (ABS) model of multiple agents (evacuee households) in a hypothetical community to investigate the impact of behaviour as an unofficial channel on the overall warning dissemination. Parameters studied include the percentage of people who warn their neighbours, the efficiency of different official warning channels, and delay time to warn neighbours. Even with a low proportion of people willing to warn their neighbour, the results showed considerable impact on the overall warning dissemination. 相似文献
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Dr. Vladimir V. Shilovskikh Alexandra A. Timralieva Pavel V. Nesterov Dr. Alexander S. Novikov Dr. Petr A. Sitnikov Prof. Elizaveta A. Konstantinova Prof. Alexander I. Kokorin Prof. Ekaterina V. Skorb 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16603-16610
In the last two decades, a large number of self-assembled materials were synthesized and they have already found their way into large-scale industry and science. Hydrogen-bond-based supramolecular adducts are found to have unique properties and to be perfect host structures for trapping target molecules or ions. Such chemical systems are believed to resemble living matter and can substitute a living cell in a number of cases. Herein, a report on an organic material based on supramolecular assembly of barbituric acid and melamine is presented. Surprisingly, the structure is found to host and stabilize radicals under mild conditions allowing its use for biological applications. The number of free radicals is found to be easily tuned by changing the pH of the environment and it increases when exposed to light up to a saturation level. We describe a preparation method as well as stability properties of melamine–barbiturate self-assembly, potentiometric titration, and hydrogen ions adsorption data and EPR spectra concerning the composite. 相似文献
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The one-pot, three-step, four-component Ugi-IMDAF reaction with 5-hydroxymethylfurfural provides simple access to hydroxymethyl-substituted epoxyisoindolones in a diastereoselective and stereospecific manner. The protocol avoids the transfer or isolation of isocyanides, and the broad scope was illustrated by the synthesis of 22 different compounds bearing various substituents on the heterocyclic core. 相似文献
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Dr. Jana Hudecová Dr. Josef Kapitán Prof. Martin Dračínský Pavel Michal Dr. Václav Profant Prof. Petr Bouř 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(59):e202202045
The histidine residue has an exceptional affinity for metals, but solution structure of its complexes are difficult to study. For zinc and nickel complexes, Raman and Raman optical activity (ROA) spectroscopy methods to investigate the link between spectral shapes and the geometry were used. The spectra were recorded and interpreted on the basis of ionic equilibria, molecular dynamics, ab initio molecular dynamics, and density functional theory. For zwitterionic histidine the dominant tautomer was determined by the decomposition of experimental spectra into calculated subspectra. An octahedral structure was found to prevail for the ZnHis2 complex in solution, in contrast to a tetrahedral arrangement in the crystal phase. The solution geometry of NiHis2 is more similar to the octahedral structure found by X-ray. The Raman and ROA structural determinations of metal complexes are dependent on extensive computations, but reveal unique information about the studied systems. 相似文献
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Annals of Global Analysis and Geometry - We study a natural class of LCK manifolds that we call integrable LCK manifolds: those where the anti-Lee form $$\eta $$ corresponds to an integrable... 相似文献