Dong Hwan

Background: Numerous studies have explored factors impacting osteoarthritis (OA), but its relationship with height remains uncertain. This study investigates the relationship between height and osteoarthritis risk in South Korea. Methods: Participants aged 50 or older who underwent health screenings in 2009 were selected from the National Health Insurance System database. A total of 1,138,904 subjects were divided into height quartiles (Q1–Q4) based on age and gender. Cox proportional hazard models were used to assess knee osteoarthritis incidence risk, with the shortest quartile (Q1) as the reference. Results: After adjusting for age, sex, income, smoking, drinking, exercise, hypertension, diabetes mellitus, dyslipidemia, and body mass index (BMI), no significant difference in OA incidence risk based on height was observed. However, when adjusted for weight instead of BMI, we observed a gradual decrease in hazard ratio with increasing height. The hazard ratio for the tallest group was 0.787 (95% CI, 0.781~0.795). Similar results were obtained in all subgroups. Conclusions: Compared to previous studies, our findings present a clear distinction. Therefore, there may be racial differences in the association between height and knee OA risk, and our study provides evidence that, in East Asian populations, taller individuals have a reduced risk of knee OA.

We synthesized novel polyelectrolytes based on naphthalene diimide with quaternary amine featuring hydroxyl groups at the side chain, along with different counteranions (PF-NDIN-Br-OH and PF-NDIN-I-OH) for polymer solar cell (PSC) application as the interlayer. The polyelectrolytes establish a beneficial interface dipole through the ionic moieties and synergistic effects arising from the hydroxyl groups located at the side chain. Incorporating polyelectrolytes as the cathode interlayer resulted in an enhancement of the power conversion efficiency (PCE). The PCE of the device with PF-NDIN-Br-OH increased from 8.96% to 9.51% compared to the ZnO-only device. The best PCE was obtained with the device based on PF-NDIN-I-OH, up to 9.59% resulting from the Jsc enhancement. This outcome implies a correlation between the performance of the device and the synergistic effects observed in polyelectrolytes containing hydroxyl groups in the side chain, along with larger anions when employed in PSCs.

In previous studies, difficulties were encountered in measuring changes within high-pressure vessels owing to limitations such as sensor connectors and sensor failures under high-pressure conditions. In addition, polymer–gas mixtures experience instantaneous gas desorption upon exiting high-pressure vessels owing to pressure differentials, leading to measurement errors. In this study, a device using magnetic sensors was developed to measure the real-time changes in gas-saturated polymers inside pressure vessels. Experiments on polymethyl methacrylate gas adsorption were conducted with parameters including pressure at 5 MPa and temperatures ranging from −20 to 40 °C for 60 and 180 min. It was observed that at −20 °C, the maximum magnetic field force density and deflection were 391.53 μT and 5.83 mm, respectively, whereas at 40 °C, deflection did not occur, with a value of 321.79 μT. Based on gas saturation experiments, a new model for deflection in high-pressure atmospheres is proposed. Additionally, an ANSYS analysis was conducted to predict the changes in Young's modulus based on gas saturation. In previous studies, mechanical properties were measured outside the pressure vessel, resulting in an error due to a pressure difference, while the proposed method is characterized by the ability to directly measure polymer behavior according to gas saturation in high-pressure vessels using a magnetic sensor in real time. Therefore, it is possible to predict polymer behavior, making it easy to control variables in high-pressure polymer processes.

Astrocytes in the brain contribute to various essential functions, including maintenance of the neuronal framework, survival, communication, metabolic processes, and neurotransmitter levels. Leucine-rich repeat kinase 2 (LRRK2) is associated with the pathogenesis of Parkinson's disease (PD). LRRK2 is expressed in neurons, microglia, and astrocytes and plays diverse roles in these cell types. We aimed to determine the effects of mutant human G2019S-LRRK2 (GS-hLRRK2) in rat primary astrocytes (rASTROs). Transfection with GS-hLRRK2 significantly decreased cell viability compared to transfection with the vector and wild-type human LRRK2 (WT-hLRRK2). GS-hLRRK2 expression significantly reduced the levels of nerve growth factor and increased the levels of proinflammatory cytokines (interleukin-1β and tumor necrosis factor α) compared to the vector and WT-hLRRK2 expression. Furthermore, GS-hLRRK2 expression in rASTROs promoted astrogliosis, which was characterized by increased expression of glial fibrillary acidic protein and vimentin. Treatment with the conditioned medium of G2019S LRRK2-expressing rASTROs decreased N27 cell viability compared to treatment with that of WT-hLRRK2-expressing rASTROs. Consequently, the regulation of the dopamine synthesis pathway was affected in N27 cells, thereby leading to altered levels of tyrosine hydroxylase, dopamine transporter, Nurr1, and dopamine release. Overall, the G2019S LRRK2 mutation disrupted astrocyte function, thereby aggravating PD progression.

Lee, Dong Hwan MD, PhD ; Kim, Yun Hwan MD ; Baek, Jaeyoon MD ; Kim, Seon Ae PhD Kim, Seok Jung MD, PhD Abstract

Department of Korean Medicine Rehabilitation, Haeundae Jaseng Hospital of Korean Medicine, 793 Haeun-daero, Haeundae-gu, Busan 48102, Republic of Korea

Division of Infectious Diseases, Department of Internal Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14066, Republic of Korea

Abstract To investigate disparities in sensitisation to Staphylococcus aureus enterotoxin A/B (SEA/SEB) and olfactory function in patients

Recent progress in hand gesture recognition has introduced several natural and intuitive approaches to drone control. However, effectively maneuvering drones in complex environments remains challenging. Drone movements are governed by four independent factors: roll, yaw, pitch, and throttle. Each factor includes three distinct behaviors—increase, decrease, and neutral—necessitating hand gesture vocabularies capable of expressing at least 81 combinations for comprehensive drone control in diverse scenarios. In this paper, we introduce a new set of hand gestures for precise drone control, leveraging an RGB camera sensor. These gestures are categorized into motion-based and posture-based types for efficient management. Then, we develop a lightweight hand gesture recognition algorithm capable of real-time operation on even edge devices, ensuring accurate and timely recognition. Subsequently, we integrate hand gesture recognition into a drone simulator to execute 81 commands for drone flight. Overall, the proposed hand gestures and recognition system offer natural control for complex drone maneuvers.

Abstract This bicenter retrospective analysis included 162 patients who had undergone prostate biopsy following prebiopsy MRI, excluding