The Association of Black Cardiologists (ABC) Cardiovascular Implementation Study (CVIS): A Research Registry Integrating Social Determinants to Support Care for Underserved Patients.

African Americans, other minorities and underserved populations are consistently under- represented in clinical trials. Such underrepresentation results in a gap in the evidence base, and health disparities. The ABC Cardiovascular Implementation Study (CVIS) is a comprehensive prospective cohort registry that integrates social determinants of health.

Effect of β-blocker Therapy on Hospital Readmission and Mortality in Heart Failure Patients With Concurrent Cocaine Use.

Background: β-Blockers are first-line agents for reduction in symptoms, hospitalization, and mortality in patients with heart failure having reduced ejection fraction (HFrEF). However, the safety and efficacy of continuous β-blocker therapy (BBT) in patients who actively use cocaine remain controversial, and available literature is limited. We aimed to evaluate the effect of BBT on hospital readmission and mortality in patients having HFrEF with concurrent cocaine use.

Risk factors for acute non-ST-segment elevation myocardial infarction in a population sample of predominantly African American patients with chest pain and normal coronary arteries.

Background: We sought to investigate the relationship between echocardiographic left ventricular hypertrophy (LVH) and acute non-ST-elevation segment myocardial infarction (NSTE-MI) in patients with chest pain and angiographically normal coronary arteries.

Methods: Retrospective analysis of patients admitted for acute chest pain in a large urban hospital serving predominantly African American patients.

Results: 131 (of 700) patients had normal coronary arteries or only minimal luminal irregularities (ie, <10% luminal narrowing) on cardiac angiography and available cardiac biomarker data to define the presence or absence of MI.

Evidence for nanoscale two-dimensional Co clusters in CoPt3 films with perpendicular magnetic anisotropy.

The length scale of the local chemical anisotropy responsible for the growth-temperature-induced perpendicular magnetic anisotropy of face-centered cubic CoPt(3) alloy films was investigated using polarized extended x-ray absorption fine structure (EXAFS). These x-ray measurements were performed on a series of four (111) CoPt(3) films epitaxially grown on (0001) sapphire substrates. The EXAFS data show a preference for Co-Co pairs parallel to the film plane when the film exhibits magnetic anisotropy, and random chemical order otherwise.

Local structure of uncapped and capped InGaN/GaN quantum dots.

The local structure around the indium atoms in uncapped and capped In(x)Ga(1-x)N quantum dots has been studied by In K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. The samples were grown by metal organic vapour phase epitaxy. The EXAFS was successfully applied to study the structural properties of buried quantum dots which are not optically active.

The local electronic structure of alpha-Li3N.

New theoretical and experimental investigations of the occupied and unoccupied local electronic densities of states (DOS) are reported for alpha-Li(3)N. Band-structure and density-functional theory calculations confirm the absence of covalent bonding character. However, real-space full-multiple-scattering (RSFMS) calculations of the occupied local DOS find less extreme nominal valences than have previously been proposed.

End-to-end stacking and liquid crystal condensation of 6 to 20 base pair DNA duplexes.

Short complementary B-form DNA oligomers, 6 to 20 base pairs in length, are found to exhibit nematic and columnar liquid crystal phases, even though such duplexes lack the shape anisotropy required for liquid crystal ordering. Structural study shows that these phases are produced by the end-to-end adhesion and consequent stacking of the duplex oligomers into polydisperse anisotropic rod-shaped aggregates, which can order into liquid crystals. Upon cooling mixed solutions of short DNA oligomers, in which only a small fraction of the DNA present is complementary, the duplex-forming oligomers phase-separate into liquid crystal droplets, leaving the unpaired single strands in isotropic solution.

Sample-angle feedback for diffraction anomalous fine-structure spectroscopy.

Diffraction anomalous fine-structure (DAFS) experiments measure Bragg peak intensities as continuous functions of photon energy near a core-level excitation. Measuring the integrated intensity at each energy makes the experiments prohibitively slow; however, in many cases DAFS can be collected quickly by measuring only the peak intensity at the center of the rocking curve. A piezoelectric-actuator-driven stage has been designed and tested as part of a sample-angle feedback circuit for locking onto the maximum of the rocking curve while the energy is scanned.

Zinc and mechanical prowess in the jaws of Nereis, a marine worm.

Higher animals typically rely on calcification to harden certain tissues such as bones and teeth. Some notable exceptions can be found in invertebrates: The fangs, teeth, and mandibles of diverse arthropod species have been reported to contain high levels of zinc. Considerable quantities of zinc also occur in the jaws of the marine polychaete worm Nereis sp.

Direct determination of epitaxial interface structure in Gd2O3 passivation of GaAs.

Obtaining accurate structural information on epitaxial films and interfaces is nowhere more critical than in semiconductor passivation layers, where details of the atomic structure and bonding determine the nature of the interface electronic states. Various non-destructive methods have been used to investigate the structure of films and interfaces, but their interpretation is model-dependent, leading occasionally to wrong conclusions. We have developed a new X-ray method for the direct determination of epitaxial structures, coherent Bragg rod analysis (COBRA).

Direct separation of short range order in intermixed nanocrystalline and amorphous phases.

Diffraction anomalous fine-structure (DAFS) and extended x-ray absorption fine-structure (EXAFS) measurements were combined to determine short range order (SRO) about a single atomic type in a sample of mixed amorphous and nanocrystalline phases of germanium. EXAFS yields information about the SRO of all Ge atoms in the sample, while DAFS determines the SRO of only the ordered fraction. We determine that the first-shell distance distribution is bimodal; the nanocrystalline distance is the same as the bulk crystal, to within 0.

Growth induced magnetic and chemical anisotropy in CoPt3 alloy films.

We report the results of polarized Co EXAFS experiments on a series of CoPt3 films grown by molecular beam epitaxy on (100) MgO singe crystal substrates over a range of temperatures from 473 K to 1073 K. These samples exhibit substantial perpendicular magnetic anisotropy that is strongly dependent on the substrate growth temperature Tg. We measure a preference for in-plane Co-Co pairs that is correlated with the magnetic properties.