Rural Residence Associated with Receipt of Recommended Post-Discharge COPD Care among a Cohort of U.S. Veterans.

Rationale: Individuals with chronic obstructive pulmonary disease (COPD) in rural areas experience inequitable access to care.

Objective: To assess whether rural residence is associated with receipt of recommended post-discharge COPD care.

Methods: We conducted a cohort study of all U.

The Impact of Changing Race-Specific Equations for Lung Function Tests among Veterans with Chronic Obstructive Pulmonary Disease.

The American Thoracic Society recommended a single reference equation for spirometry, but the impact on patients is not known. To estimate the effect of changing to a single reference equation among veterans with chronic obstructive pulmonary disease (COPD). A cross-sectional study was conducted including veterans aged ⩾40 to ⩽89 years with COPD and spirometry results from 21 facilities between 2010 and 2019.

Area-Level Socioeconomic Disadvantage and Health Care Spending: A Systematic Review.

Importance: Publicly available, US Census-based composite measures of socioeconomic disadvantage are increasingly being used in a wide range of clinical outcomes and health services research. Area Deprivation Index (ADI) and Social Vulnerability Index (SVI) are 2 of the most commonly used measures. There is also early interest in incorporating area-level measures to create more equitable alternative payment models.

Unraveling Excited State Dynamics of a Single-Stranded DNA-Assembled Conjugated Polyelectrolyte.

Conformational templating of conjugated polyelectrolytes with single-stranded DNAs (ssDNAs) has the prospect of tailoring excited state dynamics for specific optoelectronic applications. We use ultrafast time-resolved infrared spectroscopy to study the photophysics of a cationic polythiophene assembled with different ssDNAs, inducing distinct conformations (flexible disordered structures vs more rigid complexes with increased backbone planarity). Intrachain polarons are always produced upon selective excitation of the polymer, the extent being dependent on backbone torsional order.

Sleep Testing and Mortality in a Propensity-matched Cohort of Patients with Chronic Obstructive Pulmonary Disease.

Many advocate the application of propensity-matching methods to real-world data to answer key questions around obstructive sleep apnea (OSA) management. One such question is whether identifying undiagnosed OSA impacts mortality in high-risk populations, such as those with chronic obstructive pulmonary disease (COPD). Assess the association of sleep testing with mortality among patients with COPD and a high likelihood of undiagnosed OSA.

Resolving the Chemical Formula of Nesquehonite via NMR Crystallography, DFT Computation, and Complementary Neutron Diffraction.

Nesquehonite is a magnesium carbonate mineral relevant to carbon sequestration envisioned for carbon capture and storage of CO . Its chemical formula remains controversial today, assigned as either a hydrated magnesium carbonate [MgCO  ⋅ 3H O], or a hydroxy- hydrated- magnesium bicarbonate [Mg(HCO )OH ⋅ 2H O]. The resolution of this controversy is central to understanding this material's thermodynamic, phase, and chemical behavior.

Gaining Insights on the Interactions of a Class of Decorated (2-([2,2'-Bipyridin]-6-yl)phenyl)platinum Compounds with c-Myc Oncogene Promoter G-Quadruplex and Other DNA Structures.

Organometallic molecules offer some of the most promising scaffolds for interaction with G-quadruplex nucleic acids. We report the efficient synthesis of a family of organoplatinum(II) complexes, featuring a 2-([2,2'-bipyridin]-6-yl)phenyl tridentate (N N C) ligand, that incorporates peripheral side-chains aiming at enhancing and diversifying its interaction capabilities. These include a di-isopropyl carbamoyl amide, a morpholine ethylenamide, two enantiomeric proline imides and an oxazole.

Predicting the Mechanism and Products of CO Capture by Amines in the Presence of HO.

An extensive correlated molecular orbital theory study of the reactions of CO with a range of substituted amines and HO in the gas phase and aqueous solution was performed at the G3(MP2) level with a self-consistent reaction field approach. The G3(MP2) calculations were benchmarked at the CCSD(T)/CBS level for NH reactions. A catalytic NH reduces the energy barrier more than a catalytic HO for the formation of HNCOOH and HCO.

Predicting plasma conditions necessary for synthesis of γ-AlO nanocrystals.

Nonthermal plasma (NTP) offers a unique synthesis environment capable of producing nanocrystals of high melting point materials at relatively low gas temperatures. Despite the rapidly growing material library accessible through NTP synthesis, designing processes for new materials is predominantly empirically driven. Here, we report on the synthesis of both amorphous alumina and γ-Al2O3 nanocrystals and present a simple particle heating model that is suitable for predicting the plasma power necessary for crystallization.

Describing angular momentum conventions in circularly polarized optically pumped NMR in GaAs and CdTe.

The physical phenomena governing hyperpolarization through optical pumping of conduction electrons continue to be explored in multiple semiconductor systems. One early finding has been the asymmetry between the optically pumped nuclear magnetic resonance (OPNMR) signals when generated by different circular polarizations (i.e.

Preferential SO Adsorption in Mg-MOF-74 from a Humid Acid Gas Stream.

The preferential adsorption of SO versus water in Mg-MOF-74 from a humid SO gas stream has been investigated via materials studies and nuclear magnetic resonance (NMR). Mg-MOF-74 has been synthesized and subsequently loaded simultaneously with water vapor and SO (62-96 ppm) in an adsorption chamber at room temperature over a time period of 4 days with a sample taken every 24 h. Each sample was analyzed by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA)-mass spectrometry, and scanning electron microscopy-energy-dispersive spectroscopy.

Structural and Photophysical Templating of Conjugated Polyelectrolytes with Single-Stranded DNA.

A promising approach to influence and control the photophysical properties of conjugated polymers is directing their molecular conformation by templating. We explore here the templating effect of single-stranded DNA oligomers (ssDNAs) on cationic polythiophenes with the goal to uncover the intermolecular interactions that direct the polymer backbone conformation. We have comprehensively characterized the optical behavior and structure of the polythiophenes in conformationally distinct complexes depending on the sequence of nucleic bases and addressed the effect on the ultrafast excited-state relaxation.

CYP2J19 mediates carotenoid colour introgression across a natural avian hybrid zone.

It has long been of interest to identify the phenotypic traits that mediate reproductive isolation between related species, and more recently, the genes that underpin them. Much work has focused on identifying genes associated with animal colour, with the candidate gene CYP2J19 identified in laboratory studies as the ketolase converting yellow dietary carotenoids to red ketocarotenoids in birds with red pigments. However, evidence that CYP2J19 explains variation between red and yellow feather coloration in wild populations of birds is lacking.

Resonance Raman study of the J-type aggregation process of a water soluble perylene bisimide.

Perylene bisimides (PBIs) are dyes known for combining high absorption and emission in the visible region with thermal and photochemical stability. H-bond-directed aggregation driven by free imide groups has been reported to promote the uncommon J-type aggregate formation of PBIs. J-aggregates are highly desired thanks to their bathochromically shifted narrow absorption and fluorescence due to excitonic coupling, together with hyperchromicity and superradiance compared to the monomer.

NMR Crystallography: Evaluation of Hydrogen Positions in Hydromagnesite by C{ H} REDOR Solid-State NMR and Density Functional Theory Calculation of Chemical Shielding Tensors.

Solid-state NMR measurements coupled with density functional theory (DFT) calculations demonstrate how hydrogen positions can be refined in a crystalline system. The precision afforded by rotational-echo double-resonance (REDOR) NMR to interrogate C- H distances is exploited along with DFT determinations of the C tensor of carbonates (CO ). Nearby H nuclei perturb the axial symmetry of the carbonate sites in the hydrated carbonate mineral, hydromagnesite [4 MgCO ⋅Mg(OH) ⋅4 H O].

Silica-Supported Sterically Hindered Amines for CO Capture.

Most studies exploring the capture of CO on solid-supported amines have focused on unhindered amines or alkylimine polymers. It has been observed in extensive solution studies that another class of amines, namely sterically hindered amines, can exhibit enhanced CO capacity when compared to their unhindered counterparts. In contrast to solution studies, there has been limited research conducted on sterically hindered amines on solid supports.

The "Missing" Bicarbonate in CO Chemisorption Reactions on Solid Amine Sorbents.

We have identified a hydrated bicarbonate formed by chemisorption of CO on both dimethylaminopropylsilane (DMAPS) and aminopropylsilane (APS) pendant molecules grafted on SBA-15 mesoporous silica. The most commonly used sequence in solid-state NMR, C CPMAS, failed to detect bicarbonate in these solid amine sorbent samples; here, we have employed a Bloch decay ("pulse-acquire") sequence (with H decoupling) to detect such species. The water that is present contributes to the dynamic motion of the bicarbonate product, thwarting CPMAS but enabling direct C detection by shortening the spin-lattice relaxation time.

Structured Growth of Metal-Organic Framework MIL-53(Al) from Solid Aluminum Carbide Precursor.

The conventional synthesis of metal-organic frameworks (MOFs) through soluble metal-salt precursors provides little control over the growth of MOF crystals. The use of alternative metal precursors would provide a more flexible and cost-effective strategy for direction- and shape-controlled MOF synthesis. Here, we demonstrate for the first time the use of insoluble metal-carbon matrices to foster directed growth of MOFs.

N Solid State NMR Spectroscopic Study of Surface Amine Groups for Carbon Capture: 3-Aminopropylsilyl Grafted to SBA-15 Mesoporous Silica.

Materials composed of high-porosity solid supports, such as SBA-15, containing amine-bearing moieties inside the pores, such as 3-aminopropylsilane (APS), are envisioned for carbon dioxide capture; solid-state N NMR can be highly informative for studying chemisorption reactions. Two N-enriched samples with different APS loadings were studied to probe the identity of the pendant molecules and structure of the chemisorbed CO species. N cross-polarization magic-angle spinning NMR provides unique information about the amines, whether they are rigid or dynamic, by measuring contact time curves and rotating frame, T(N), relaxation.

Salt-induced thermochromism of a conjugated polyelectrolyte.

We report here the photophysical properties of a water-soluble conjugated polythiophene with cationic side-chains. When dissolved in aqueous buffer solution (PBS, phosphate buffered saline), there is ordering of the polymer chains due to the presence of the salts, in contrast to pure water, where a random-coil conformation is adopted at room temperature. The ordering leads to a pronounced colour change of the solution (the absorption maximum shifts from 400 nm to 525 nm).

A flow-through, elevated-temperature and -pressure NMR apparatus for in-situ CO sequestration studies.

We report an apparatus for in-situ nuclear magnetic resonance (NMR) studies of chemical reactions of dissolved CO with minerals (rock or powder) under continuous flow. The operating range of the apparatus is 18-150°C and 1-140bar. A flow pump is used to circulate a CO-water solution, with a heated mixing vessel where CO gas equilibrates with a water solution.

A combined experimental setup for OP and ODNMR.

Instrumentation for optically-pumped and optically-detected nuclear magnetic resonance (OPNMR and ODNMR) has been developed and implemented as a single experimental apparatus to study semiconductors such as GaAs and CdTe. These two measurement schemes use many of the same components for experiments. Here we describe, in two parts, the apparatus that can record such measurements and give examples of representative data.

Spectroscopic Characterization of Adsorbed CO on 3-Aminopropylsilyl-Modified SBA15 Mesoporous Silica.

Multiple chemisorption products are found from the interaction of CO with the solid-amine sorbent, 3-aminopropyl silane (APS), bound to mesoporous silica (SBA15) using solid-state NMR and FTIR spectroscopy. We employed a combination of both N{C} rotational-echo double-resonance (REDOR) NMR and C{N} REDOR to determine the chemical identity of these products. N{C} REDOR measurements are consistent with a single C-N pair and distance of 1.