Epidemiologic trends of patients who visited nationwide emergency departments: a report from the National Emergency Department Information System (NEDIS) of Korea, 2018-2022.

OBJECTIVE: : This study analyzed trends in emergency department (ED) visits in South Korea using the National Emergency Department Information System (NEDIS) data from 2018 to 2022. METHODS: : This was a retrospective observational study using data from the NEDIS database from 2018 to 2022. Age- and sex-standardized ED visits per 100,000 population, as well as age- and sex-standardized rates for mortality, admission, and transfer, were calculated. RESULTS: : The standardized ED visits per 100,000 population was approximately 20,000 from 2018 to 2019 and decreased to about 18,000 in 2022. The standardized mortality rate ranged from 1.4% to 1.7%. The admission rate (18.4%-19.4%) and the transfer rates (1.6%-1.8%) were similar during the study period. Approximately 5.5% of patients were triaged as Korean Triage and Acuity Scale score 1 or 2. About 91% of patients visited the ED directly and 21.7% of patients visited the ED with an ambulance. The ED length of stay was less than 6 hours in 90.3% of patients and the ED mortality rate was 0.6%. Acute gastroenteritis was the most common diagnosis. Respiratory virus symptoms, such as fever and sore throat, were also common chief complaints. CONCLUSION: : ED visits decreased during the 5-year period, while admission, transfer, and death rates remained relatively stable.

Ferroelectric Field-Effect-Transistor Integrated with Ferroelectrics Heterostructure.

To address the demands of emerging data-centric computing applications, ferroelectric field-effect transistors (Fe-FETs) are considered the forefront of semiconductor electronics owing to their energy and area efficiency and merged logic-memory functionalities. Herein, the fabrication and application of an Fe-FET, which is integrated with a van der Waals ferroelectrics heterostructure (CuInP2 S6 /α-In2 Se3 ), is reported. Leveraging enhanced polarization originating from the dipole coupling of CIPS and α-In2 Se3 , the fabricated Fe-FET exhibits a large memory window of 14.5 V at VGS = ±10 V, reaching a memory window to sweep range of ≈72%. Piezoelectric force microscopy measurements confirm the enhanced polarization-induced wider hysteresis loop of the double-stacked ferroelectrics compared to single ferroelectric layers. The Landau-Khalatnikov theory is extended to analyze the ferroelectric characteristics of a ferroelectric heterostructure, providing detailed explanations of the hysteresis behaviors and enhanced memory window formation. The fabricated Fe-FET shows nonvolatile memory characteristics, with a high on/off current ratio of over 106 , long retention time (>104 s), and stable cyclic endurance (>104 cycles). Furthermore, the applicability of the ferroelectrics heterostructure is investigated for artificial synapses and for hardware neural networks through training and inference simulation. These results provide a promising pathway for exploring low-dimensional ferroelectronics.

Two-Dimensional CIPS-InSe van der Waal Heterostructure Ferroelectric Field Effect Transistor for Nonvolatile Memory Applications.

Channel current conduction modulation with the spontaneous polarization of ferroelectric films in ferroelectric field-effect transistors (FeFETs) has been widely investigated. Low interface quality and thermodynamic instability owing to the presence of dangling bonds in the conventional ferroelectrics have limited the memory retention and endurance of FeFETs. This, in turn, prevents their commercialization. However, the atomically thin nature of 2D ferroelectric, semiconducting, and insulating films facilitate the achievement of trap-free interfaces as van der Waal heterostructures (vdWHs) to develop FeFETs with long data retention and endurance characteristics. Here, we demonstrate a 2D vdWH FeFET fabricated with ferroelectric CuInP2S6 (CIPS), hexagonal boron nitride (h-BN) as the dielectric, and InSe as the ferroelectric semiconductor channel. The device shows an excellent performance as nonvolatile memory (NVM) with its large memory window (4.6 V at a voltage sweep of 5 V), high drain current on/off ratio (>104), high endurance, and long data retention (>104 s). These results demonstrate the considerable potential of vdWHs for the development of FeFETs for logic and NVM applications.

Unstable pathological fracture of the odontoid process caused by Langerhans cell histiocytosis.

STUDY DESIGN: A case report and literature review. OBJECTIVE: To illustrate the spontaneous resolution of unstable pathological fracture of the odontoid process of the C2 caused by Langerhans cell histiocytosis (LCH) in early childhood. SUMMARY OF BACKGROUND DATA: The involvement of atlantoaxial LCH is very rare and its treatment is unfamiliar to surgeons. Therefore, the management of pediatric LCH of the odontoid process and the C2 body is challenging and must be adapted according to the patient's needs; it could range from observation to surgical intervention. METHODS: A case of pathological fracture of the odontoid process with torticollis diagnosed with LCH of the odontoid process and C2 body and involving right femur in early childhood is presented. A histopathological study showed LCH. The patient underwent brace immobilization and systemic chemotherapy. RESULTS: The patient showed successful bony remodeling without LCH recurrence on CT. The neck pain was resolved, and there was no limitation in neck movement. CONCLUSION: Immobilization and systemic chemotherapy with close observation are adequate for the management of patients despite the unstable pathological fracture of the odontoid process.