J Occup Environ Med
September 2020
Objective: In Philadelphia, a scrapyard fire generated PM2.5 concentrations >1000 μg/m. We assessed whether this was associated with pediatric emergency department visits for respiratory diagnoses.
View Article and Find Full Text PDFChildren with special health care needs (CSHCN) use relatively high quantities of healthcare resources and have overall higher morbidity than the general pediatric population. Embedding clinical pharmacists into the Patient-Centered Medical Home (PCMH) to provide comprehensive medication management (CMM) through collaborative practice agreements (CPAs) for children, especially for CSHCN, can improve outcomes, enhance the experience of care for families, and reduce the cost of care. Potential network infrastructures for collaborative practice focused on CSHCN populations, common language and terminology for CMM, and clinical pharmacist workforce estimates are provided.
View Article and Find Full Text PDFThe photophysical properties of oligosilanes show unique conformational dependence due to σ-electron delocalization. The excited states of the SAS, AAS, and AEA conformations of peralkylated n-hexasilanes, in which the SiSiSiSi dihedral angles are controlled into a syn (S), anti (A), or eclipsed (E) conformation, were investigated by using UV absorption, magnetic circular dichroism (MCD), and linear dichroism spectroscopy. Simultaneous Gaussian fitting of all three spectra identified a minimal set of transitions and the wavenumbers, oscillator strengths, and MCD B terms in all three compounds.
View Article and Find Full Text PDFUnlike π-electron chromophores, the peralkylated n-tetrasilane σ-electron chromophore resembles a chameleon in that its electronic spectrum changes dramatically as its silicon backbone is twisted almost effortlessly from the syn to the anti conformation (changing the SiSiSiSi dihedral angle ω from 0 to 180°). A combination of UV absorption, magnetic circular dichroism (MCD), and linear dichroism (LD) spectroscopy on conformationally controlled tetrasilanes 1-9, which cover fairly evenly the full range of angles ω, permitted a construction of an experimental correlation diagram for three to four lowest valence electronic states. The free chain tetrasilane n-Si4 Me10 (10), normally present as a mixture of three enantiomeric conformer pairs of widely different angles ω, has also been included in our study.
View Article and Find Full Text PDFA molecular rotor in which a naphthalene rotator is attached through a silicon atom to three fatty acid chains has been synthesized, and Langmuir-Blodgett techniques were used to deposit on silica surfaces monolayers of its calcium salt, both neat and diluted with stearic acid salts. The monolayer films have been characterized by ellipsometry and Fourier transform infrared (FT-IR) grazing-incidence attenuated total internal reflection (GATR) spectroscopy on Si-SiO(2) and by UV-vis absorption spectroscopy on SiO(2). The measurements were combined with calculations of the electronic (INDO/S) and vibrational (DFT) transition moment directions to deduce the average orientation of the rotor molecules, including the naphthalene ring, relative to the surface.
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