Registered Nurse Staffing and Inpatient Outcomes in Korean Long-Term Care Hospitals.

Background/objectives: There is a relative lack of specific research on registered nurse (RN) staffing in long-term care hospitals in the Republic of Korea. This study investigated the association between RN staffing levels and inpatient outcomes in long-term care hospitals in the Republic of Korea.

Methods: Nationwide data of long-term care hospitals from the Health Insurance Review and Assessment Services website were used to analyze the association between registered nurse staffing levels and 7 inpatient outcome indicators.

Evidence of a magnetic transition in atomically thin CrTiCT MXene.

Two-dimensional (2D) transition metal carbides and nitrides known as MXenes have shown attractive functionalities such as high electronic conductivity, a wide range of optical properties, versatile transition metal and surface chemistry, and solution processability. Although extensively studied computationally, the magnetic properties of this large family of 2D materials await experimental exploration. 2D magnetic materials have recently attracted significant interest as model systems to understand low-dimensional magnetism and for potential spintronic applications.

Electronic and optical characterization of 2D TiC and NbC (MXene) thin films.

Two-dimensional (2D) transition metal carbides and/or nitrides (MXenes) are a new class of 2D materials, with extensive opportunities for property tailoring due to the numerous possibilities for varying chemistries and surface terminations. Here, TiAlC and NbAlC MAX phase epitaxial thin films were deposited on sapphire substrates by physical vapor deposition. The films were then etched in LiF/HCl solutions, yielding Li-intercalated, 2D TiCT and NbCT films, whose terminations, transport and optical properties were characterized.

Tailoring manganese oxide with atomic precision to increase surface site availability for oxygen reduction catalysis.

Controlling the structure of catalysts at the atomic level provides an opportunity to establish detailed understanding of the catalytic form-to-function and realize new, non-equilibrium catalytic structures. Here, advanced thin-film deposition is used to control the atomic structure of LaSrMnO, a well-known catalyst for the oxygen reduction reaction. The surface and sub-surface is customized, whereas the overall composition and d-electron configuration of the oxide is kept constant.

Polar Oxides without Inversion Symmetry through Vacancy and Chemical Order.

One synthetic modality for materials discovery proceeds by forming mixtures of two or more compounds. In transition metal oxides (TMOs), chemical substitution often obeys Vegard's principle, and the resulting structure and properties of the derived phase follow from its components. A change in the assembly of the components into a digital nanostructure, however, can stabilize new polymorphs and properties not observed in the constituents.

Control of electronic properties of 2D carbides (MXenes) by manipulating their transition metal layers.

In this study, a transition from metallic to semiconducting-like behavior has been demonstrated in two-dimensional (2D) transition metal carbides by replacing titanium with molybdenum in the outer transition metal (M) layers of MC and MC MXenes. The MXene structure consists of n + 1 layers of near-close packed M layers with C or N occupying the octahedral site between them in an [MX]M arrangement. Recently, two new families of ordered 2D double transition metal carbides MXenes were discovered, M'M''C and M'M''C- where M' and M'' are two different early transition metals, such as Mo, Cr, Ta, Nb, V, and Ti.

Control of functional responses via reversible oxygen loss in La₁-xSrxFeO₃-δ films.

La0.3 Sr0.7 FeO3-δ films undergo dramatic changes in electronic and optical properties due to reversible oxygen loss induced by low-temperature heating.

Fluorination of epitaxial oxides: synthesis of perovskite oxyfluoride thin films.

While the synthesis of ABO3 perovskite films has enabled new strategies to control the functionality of this material class, the chemistries that have been realized in thin film form constitute only a fraction of those accessible to bulk chemists. Here, we report the synthesis of oxyfluoride films, where the incorporation of F may provide a new means to tune physical properties in thin films by modifying electronic structure. Fluorination is achieved by spin coating a poly(vinylidene fluoride) (PVDF) solution onto oxygen-deficient films.

Plasmon response of a quantum-confined electron gas probed by core-level photoemission.

We demonstrate the existence of quantized "bulk" plasmons in ultrathin magnesium films on Si(111) by analyzing plasmon-loss satellites in core-level photoemission spectra, recorded as a function of the film thickness d. Remarkably, the plasmon energy is shown to vary as 1/d2 all the way down to three atomic layers. The loss spectra are dominated by the n=1 and n=2 normal modes, consistent with the excitation of plasmons involving quantized electronic subbands.