Electrocatalysts for Zinc-Air Batteries Featuring Single Molybdenum Atoms in a Nitrogen-Doped Carbon Framework.

Bifunctional catalysts can facilitate two different electrochemical reactions with conflicting characteristics. Here, a highly reversible bifunctional electrocatalyst for rechargeable zinc-air batteries (ZABs) is reported featuring a "core-shell structure" in which N-doped graphene sheets wrap around vanadium molybdenum oxynitride nanoparticles. Single Mo atoms are released from the particle core during synthesis and anchored to electronegative N-dopant species in the graphitic shell.

Dispersion and stability mechanism of Pt nanoparticles on transition-metal oxides.

The heterogeneous catalysts of Pt/transition-metal oxides are typically synthesized through calcination at 500 °C, and Pt nanoparticles are uniformly and highly dispersed when hydrogen peroxide (HO) is applied before calcination. The influence of HO on the dispersion and the stability of Pt nanoparticles on titania-incorporated fumed silica (Pt/Ti-FS) supports was examined using X-ray absorption fine structure (XAFS) measurements at the Pt L and Ti K edges as well as density functional theory (DFT) calculations. The local structural and chemical properties around Pt and Ti atoms of Pt/Ti-FS with and without HO treatment were monitored using in-situ XAFS during heating from room temperature to 500 °C.

Reduction of Transition-Metal Columbite-Tantalite as a Highly Efficient Electrocatalyst for Water Splitting.

We successfully report a liquid-liquid chemical reduction and hydrothermal synthesis of a highly stable columbite-tantalite electrocatalyst with remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance in acidic media. The reduced FeMnNbTaO (CTr) electrocatalyst shows a low overpotential of 84.23 mV at 10 mA cm and 103.

Crystallization of Transition-Metal Oxides in Aqueous Solution beyond Ostwald Ripening.

The crystallization mechanism of transition-metal oxides (TMOs) in a solution was examined based on ZnO crystallization using in-situ x-ray absorption fine structure (XAFS) measurements at the Zn K edge and semi-empirical quantum chemistry (SEQC) simulations. The XAFS results quantitatively determine the local structural and chemical properties around a zinc atom at successive stages from Zn(NO) to ZnO in an aqueous solution. The results also show that a zinc atom in Zn(NO) ions dissolves in a solution and bonds with approximately three oxygen atoms at room temperature (RT).

Mechanical Properties and Chemical Durability of Nafion/Sulfonated Graphene Oxide/Cerium Oxide Composite Membranes for Fuel-Cell Applications.

To improve both the mechanical and chemical durability of Nafion membranes for polymer electrolyte membrane fuel-cells (PEMFCs), Nafion composite membranes containing sulfonated graphene oxide (SGO) and cerium oxide (CeO; ceria) were prepared by solution casting. The structure and chemical composition of SGO were investigated by FT-IR and XPS. The effect of the sulfonation, addition of SGO and ceria on the mechanical properties, proton conductivity, and chemical stability were evaluated.

Clinical Application of Modified Burns Wean Assessment Program Scores at First Spontaneous Breathing Trial in Weaning Patients from Mechanical Ventilation.

Background: The purpose of this study was to evaluate the clinical application of modified Burns Wean Assessment Program (m-BWAP) scoring at first spontaneous breathing trial (SBT) as a predictor of successful liberation from mechanical ventilation (MV) in patients with endotracheal intubation.

Methods: Patients requiring MV for more than 72 hours and undergoing more than one SBT in a medical intensive care unit (ICU) were prospectively enrolled over a 3-year period. The m-BWAP score at first SBT was obtained by a critical care nursing practitioner.

Association between Medical Costs and the ProVent Model in Patients Requiring Prolonged Mechanical Ventilation.

Background: The purpose of this study was to determine whether components of the ProVent model can predict the high medical costs in Korean patients requiring at least 21 days of mechanical ventilation (prolonged mechanical ventilation [PMV]).

Methods: Retrospective data from 302 patients (61.6% male; median age, 63.

Clinical Utility of Rapid Pathogen Identification for Detecting the Causative Organisms in Sepsis: A Single-Center Study in Korea.

Purpose: The aim of this pre- and postintervention cohort study was evaluating how effectively rapid pathogen identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) detected the causative organisms in sepsis.

Methods: All consecutive adult patients who had bacteremia within 72 h of intensive care unit admission and met ≥2 quick Sequential Organ Failure Assessment criteria at intensive care unit admission were analyzed. The patients whose microorganisms were identified via MALDI-TOF MS between March 2014 and February 2016 formed the postintervention group.

Clinical Application of the Quick Sepsis-Related Organ Failure Assessment Score at Intensive Care Unit Admission in Patients with Bacteremia: A Single-Center Experience of Korea.

Background: We evaluated the clinical usefulness of the quick Sepsis-Related Organ Failure Assessment (qSOFA) score (based on the 2016 definition of sepsis) at intensive care unit admission in Korean patients with bacteremia.

Methods: We retrospectively analyzed clinical data from 236 patients between March 2011 and February 2016. In addition to the qSOFA, the Modified Early Warning score (MEWS) and systemic inflammatory response syndrome (SIRS) criteria were calculated.

Amorphous Cobalt Phyllosilicate with Layered Crystalline Motifs as Water Oxidation Catalyst.

The development of a high-performance oxygen evolution reaction (OER) catalyst is pivotal for the practical realization of a water-splitting system. Although an extensive search for OER catalysts has been performed in the past decades, cost-effective catalysts remain elusive. Herein, an amorphous cobalt phyllosilicate (ACP) with layered crystalline motif prepared by a room-temperature precipitation is introduced as a new OER catalyst; this material exhibits a remarkably low overpotential (η ≈ 367 mV for a current density of 10 mA cm ).

Clinical application of the ProVent score in Korean patients requiring prolonged mechanical ventilation: A 10-year experience in a university-affiliated tertiary hospital.

Purpose: We evaluated the clinical usefulness of a prognostic scoring system ("the ProVent score") in Korean patients requiring prolonged mechanical ventilation.

Material And Methods: We retrospectively analyzed the data of 184 patients in a medical intensive care unit of a tertiary care hospital between January 2004 and December 2013.

Results: The patients' median age was 65 years, and 66.

Outcomes and prognostic factors in patients with prolonged acute mechanical ventilation: A single-center study in Korea.

Purpose: The purpose of the study is to evaluate outcomes and objective parameters related to poor prognosis in patients who were defined as prolonged acute mechanical ventilation (PAMV; ventilator care ≥96 hours) in the medical intensive care unit of a university-affiliated tertiary care hospital in Korea.

Material And Methods: We analyzed retrospectively clinical data gathered from the medical records on day 4 of MV between 2008 and 2013. In total, 311 were categorized as PAMV.

Animal models of periventricular leukomalacia.

Periventricular leukomalacia, specifically characterized as white matter injury, in neonates is strongly associated with the damage of pre-myelinating oligodendrocytes. Clinical data suggest that hypoxia-ischemia during delivery and intrauterine or neonatal infection-inflammation are important factors in the etiology of periventricular leukomalacia including cerebral palsy, a serious case exhibiting neurobehavioral deficits of periventricular leukomalacia. In order to explore the pathophysiological mechanisms of white matter injury and to better understand how infectious agents may affect the vulnerability of the immature brain to injury, novel animal models have been developed using hypoperfusion, microbes or bacterial products (lipopolysaccharide) and excitotoxins.

Local structural and optical properties of ZnO nanoparticles.

This study examined the local structural and optical properties of ZnO nanoparticles (NPs) with mean diameters of 4.5 and 70 nm using extended X-ray absorption fine structure (EXAFS) measurements at the Zn K edge and photoluminescence (PL) measurements. EXAFS revealed that the average bond length of atomic pairs in the NPs was shorter than that of the powder.