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When social groups compete for members, the resulting dynamics may be understandable with mathematical models. We demonstrate that a simple ordinary differential equation (ODE) model is a good fit for religious shift by comparing it to a new international data set tracking religious nonaffiliation. We then generalize the model to include the possibility of nontrivial social interaction networks and examine the limiting case of a continuous system. Analytical and numerical predictions of this generalized system, which is robust to polarizing perturbations, match those of the original ODE model and justify its agreement with real-world data. The resulting predictions highlight possible causes of social shift and suggest future lines of research in both physics and sociology. 相似文献
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A Visible‐Light‐Mediated Radical Smiles Rearrangement and its Application to the Synthesis of a Difluoro‐Substituted Spirocyclic ORL‐1 Antagonist 下载免费PDF全文
Dr. James J. Douglas Haley Albright Martin J. Sevrin Dr. Kevin P. Cole Prof. Corey R. J. Stephenson 《Angewandte Chemie (International ed. in English)》2015,54(49):14898-14902
A visible‐light‐mediated radical Smiles rearrangement has been developed to address the challenging synthesis of the gem‐difluoro group present in an opioid receptor‐like 1 (ORL‐1) antagonist that is currently in development for the treatment of depression and/or obesity. This method enables the direct and efficient introduction of the difluoroethanol motif into a range of aryl and heteroaryl systems, representing a new disconnection for the synthesis of this versatile moiety. When applied to the target compound, the photochemical step could be conducted on 15 g scale using industrially relevant [Ru(bpy)3Cl2] catalyst loadings of 0.01 mol %. This transformation is part of an overall five‐step route to the antagonist that compares favorably to the current synthetic sequence and demonstrates, in this specific case, a clear strategic benefit of photocatalysis. 相似文献
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Chris L. Vonnegut Airlia M. Shonkwiler Muhammad M. Khalifa Dr. Lev N. Zakharov Prof. Darren W. Johnson Prof. Michael M. Haley 《Angewandte Chemie (International ed. in English)》2015,54(45):13318-13322
Treatment of 2‐ethynylanilines with P(OPh)3 gives either 2,2‐diphenoxy‐2‐λ5‐phosphaquinolines or 2‐phenoxy‐2‐λ5‐phosphaquinolin‐2‐ones under transition‐metal‐free conditions. This reaction offers access to an underexplored heterocycle, which opens up the study of the fundamental nature of the N?PV double bond and its potential for delocalization within a cyclic π‐electron system. This heterocycle can serve as a carbostyril mimic, with application as a bioisostere for pharmaceuticals based on the 2‐quinolinone scaffold. It also holds promise as a new fluorophore, since initial screening reveals quantum yields upwards of 40 %, Stokes shifts of 50–150 nm, and emission wavelengths of 380–540 nm. The phosphaquinolin‐2‐ones possess one of the strongest solution‐state dimerization constants for a D–A system (130 M ?1) owing to the close proximity of a strong acceptor (P?O) and a strong donor (phosphonamidate N? H), which suggests that they might hold promise as new hydrogen‐bonding hosts for optoelectronic sensing. 相似文献
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