Rationally designed laterally-condensed-catalysts deliver robust activity and selectivity for ethylene production in acetylene hydrogenation.

Future carbon management strategies require storage in elemental form, achievable through a sequence of CO hydrogenation reactions. Hydrogen is recycled from molecular intermediates by dehydrogenation, and side product acetylene selectively hydrogenated to ethylene. Existing Pd alloy catalysts for gas purification underperform in concentrated feeds, necessitating novel concepts.

Interpreting ultrafast electron transfer on surfaces with a converged first-principles Newns-Anderson chemisorption function.

We study the electronic coupling between an adsorbate and a metal surface by calculating tunneling matrix elements Had directly from first principles. For this, we employ a projection of the Kohn-Sham Hamiltonian upon a diabatic basis using a version of the popular projection-operator diabatization approach. An appropriate integration of couplings over the Brillouin zone allows the first calculation of a size-convergent Newns-Anderson chemisorption function, a coupling-weighted density of states measuring the line broadening of an adsorbate frontier state upon adsorption.

Physics-inspired machine learning of localized intensive properties.

Machine learning (ML) has been widely applied to chemical property prediction, most prominently for the energies and forces in molecules and materials. The strong interest in predicting energies in particular has led to a 'local energy'-based paradigm for modern atomistic ML models, which ensures size-extensivity and a linear scaling of computational cost with system size. However, many electronic properties (such as excitation energies or ionization energies) do not necessarily scale linearly with system size and may even be spatially localized.

Recurrent Co-Option and Recombination of Cytokine and Three Finger Proteins in Multiple Reproductive Tissues Throughout Salamander Evolution.

Reproductive proteins evolve at unparalleled rates, resulting in tremendous diversity of both molecular composition and biochemical function between gametes of different taxonomic clades. To date, the proteomic composition of amphibian gametes is largely a molecular mystery, particularly for Urodeles (salamanders and newts) for which few genomic-scale resources exist. In this study, we provide the first detailed molecular characterization of gametes from two salamander species ( and ) that are models of reproductive behavior.

Subvalent mixed SiGe oligomers: (ClSi)Ge and Cl(MeEtN)SiGe(SiCl).

(ClSi)Ge (1; 91%) is accessible from GeCl, the SiCl/[BuN]Cl silylation system, and excess SiCl. A key intermediate step involves Cl sequestration with AlCl in the course of the reaction between the first-formed germanide [(ClSi)Ge] and SiCl. The related adduct Cl(MeEtN)SiGe(SiCl) (2; quantitative conversion) was prepared either by amine-induced cleavage of 1 or by a bottom-up synthesis starting from GeCl and SiCl.

Active discovery of organic semiconductors.

The versatility of organic molecules generates a rich design space for organic semiconductors (OSCs) considered for electronics applications. Offering unparalleled promise for materials discovery, the vastness of this design space also dictates efficient search strategies. Here, we present an active machine learning (AML) approach that explores an unlimited search space through consecutive application of molecular morphing operations.

Improved Projection-Operator Diabatization Schemes for the Calculation of Electronic Coupling Values.

We address a long-standing ambiguity in the DFT-based projection-operator diabatization method for charge transfer couplings in donor-acceptor systems. It has long been known that the original method yields diabats which are not strictly fragment-localized due to mixing arising from basis-set orthogonalization. We demonstrate that this can contribute to a severe underestimation of coupling strengths and a spurious dependence on the choice of the basis set.

Mapping Materials and Molecules.

The visualization of data is indispensable in scientific research, from the early stages when human insight forms to the final step of communicating results. In computational physics, chemistry and materials science, it can be as simple as making a scatter plot or as straightforward as looking through the snapshots of atomic positions manually. However, as a result of the "big data" revolution, these conventional approaches are often inadequate.

Atomic structures and orbital energies of 61,489 crystal-forming organic molecules.

Data science and machine learning in materials science require large datasets of technologically relevant molecules or materials. Currently, publicly available molecular datasets with realistic molecular geometries and spectral properties are rare. We here supply a diverse benchmark spectroscopy dataset of 61,489 molecules extracted from organic crystals in the Cambridge Structural Database (CSD), denoted OE62.

Towards density functional approximations from coupled cluster correlation energy densities.

(Semi)local density functional approximations (DFAs) are the workhorse electronic structure methods in condensed matter theory and surface science. The correlation energy density ϵ(r) (a spatial function that yields the correlation energy E upon integration) is central to defining such DFAs. Unlike E, ϵ(r) is not uniquely defined, however.

Chemical diversity in molecular orbital energy predictions with kernel ridge regression.

Instant machine learning predictions of molecular properties are desirable for materials design, but the predictive power of the methodology is mainly tested on well-known benchmark datasets. Here, we investigate the performance of machine learning with kernel ridge regression (KRR) for the prediction of molecular orbital energies on three large datasets: the standard QM9 small organic molecules set, amino acid and dipeptide conformers, and organic crystal-forming molecules extracted from the Cambridge Structural Database. We focus on the prediction of highest occupied molecular orbital (HOMO) energies, computed at the density-functional level of theory.

Generalized molecular solvation in non-aqueous solutions by a single parameter implicit solvation scheme.

In computer simulations of solvation effects on chemical reactions, continuum modeling techniques regain popularity as a way to efficiently circumvent an otherwise costly sampling of solvent degrees of freedom. As effective techniques, such implicit solvation models always depend on a number of parameters that need to be determined earlier. In the past, the focus lay mostly on an accurate parametrization of water models.

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities.

Trichlorosilylated tetrelides [(Cl Si) E] have been prepared by adding 1 equiv of a soluble Cl salt to (Cl Si) Si (E=Si) or 4 Si Cl /GeCl (E=Ge). To assess their donor qualities, the anions [(Cl Si) E] (E=C, Si, Ge) have been treated with BCl , AlCl , and GaCl . Both BCl and GaCl give 1:1 adducts with the anionic centers.

TFAM overexpression reduces pathological cardiac remodeling.

Heart failure (HF) is a functional lack of myocardial performance due to a loss of molecular control over increases in calcium and ROS, resulting in proteolytic degradative advances and cardiac remodeling. Mitochondria are the molecular powerhouse of cells, shifting the sphere of cardiomyocyte stability and performance. Functional mitochondria rely on the molecular abilities of safety factors such as TFAM to maintain physiological parameters.

A Matter of Life and Death: End-of-Life Simulation to Develop Confidence in Nursing Students.

The use of simulation to provide end-of-life (EOL) education is a means to enhance self-efficacy levels among nursing students. The purpose of this exploratory study was to evaluate self-efficacy levels of nursing students and recent graduate nurses following an EOL simulation experience. Data were obtained using the Simulation Effectiveness Tool developed by Medical Education Technologies, Inc.

Behavioral interventions for antipsychotic medication-associated obesity: a randomized, controlled clinical trial.

Objective: To demonstrate the effectiveness of a Diabetes Prevention Program-inspired 12-month behavioral intervention for patients with severe mental illness (SMI) and medication-associated obesity.

Method: This randomized, controlled, parallel, superiority study screened 225 volunteers from November 2005 to August 2008 at the VA Greater Los Angeles Healthcare System. 122 outpatients with DSM-IV-diagnosed SMI taking antipsychotic medications who had ≥ 7% weight gain or body mass index (BMI) > 25 were randomized by computer-generated number to Lifestyle Balance treatment intervention (n = 60) or usual care control (n = 62) groups.

Development, implementation, and evaluation of an institutional daily awakening and spontaneous breathing trial protocol: a quality improvement project.

Introduction: While one controlled trial found that a daily awakening and spontaneous breathing trial (DA-SBT) decreases time on mechanical ventilation (MV), there is a paucity of real-world data surrounding the development, implementation, and impact of DA-SBT protocols. We describe a multidisciplinary process improvement effort in 2, 10-bed medical intensive care units (MICUs) at a 330-bed academic medical center that focused on the development, implementation, and evaluation of a new DA-SBT protocol.

Methods: A DA-SBT protocol, developed using results from a nursing survey literature and available institutional resources, was implemented after extensive clinician education and institution of quality reminders to boost use.

Ergometric performance during exercise training in men with intermittent claudication.

Objective: To determine and describe changes in weekly work, power, exercise times, and recovery times during an exercise training intervention in men with peripheral arterial disease (PAD) and intermittent calf claudication.

Design: Tracking of weekly exercise training parameters involved repeated measures over time in one group of participants. Other outcomes of this pilot study used a one-group, pretest-posttest design.

Preamputation evaluation of lower-limb skeletal muscle perfusion with H(2) (15)O positron emission tomography.

Objective: To establish whether muscle blood flow (MBF) measurements with O-water positron emission tomography could reliably identify patients with critical limb ischemia and detect and quantify a distal deficit in skeletal MBF in these cases.

Design: O-water positron emission tomography scans were performed at rest or during unloaded ankle plantar and dorsiflexion exercise of the diseased leg in 17 subjects with leg ischemia or on a randomly selected leg of 18 age-matched healthy control subjects. TcPO2 was evaluated with Novametrix monitors and perfusion of skin topically heated to 44 degrees C and adjacent nonheated areas with a Moor Instruments laser Doppler imaging scanner.

Effects of exercise training on calf tissue oxygenation in men with intermittent claudication.

Objective: To determine the effects of exercise training on calf tissue oxygenation in men with peripheral arterial disease and intermittent calf claudication.

Design: This pilot study was prospective and longitudinal and used a one-group, pretest-posttest design.

Setting: Tertiary care medical center for veterans.

Preamputation evaluation of limb perfusion with laser Doppler imaging and transcutaneous gases.

We studied 31 subjects with severe leg ischemia and 29 age-matched nonischemic control subjects to compare preamputation assessments of leg ischemia using laser Doppler imaging (LDI), transcutaneous partial pressure of oxygen (TcPO(2)), and transcutaneous partial pressure of carbon dioxide (TcPCO(2)). TcPO(2) and TcPCO(2) were evaluated with Novametrix Medical Systems, Inc, monitors (Wallingford, Connecticut) and perfusion (flux) of skin topically heated to 44 degrees C, and adjacent nonheated areas were evaluated with a Moor Laser Doppler Imager (Moor Instruments, Ltd; Devon, England). LDI flux of heated areas, its ratio to nonheated areas, and TcPO(2) (not TcPCO(2)) were lower in ischemic subjects than in control subjects.

Scanning laser-Doppler imaging of leg- and foot-skin perfusion in normal subjects: analysis of age, gender, site, and laser-type effects.

Objectives: To report normal values of skin perfusion in healthy subjects in three age groups using a laser Doppler imager; to determine differences attributable to gender, age, site, and use of red or near-infrared lasers; and to correlate transcutaneous oxygen with laser flux values.

Design: Flux and transcutaneous oxygen were measured at ten sites in the lower extremity in 60 subjects from three age groups. Heated and unheated sites were scanned with red and near-infrared lasers.