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Introduction: Parkinson's disease (PD) is characterized by motor and cognitive impairments that often manifest as distinct motor subtypes: Postural Instability Gait Difficulty (PIGD) and Tremor-Dominant (TD). Motor–cognitive interference, especially under dual-task (DT) walking conditions, may vary by subtype, providing insights into specific impairments. This study explored DT interference effects in PD subtypes, focusing on the potential impact of self-reported physical activity, which may help mitigate subtype-specific impairments and improve motor–cognitive function. Methods: PD patients classified as PIGD or TD and healthy controls completed single-task (ST) and DT walking assessments involving different cognitive tasks (Serial Subtraction, Auditory Stroop, and Clock Task). Physical activity levels were evaluated using the CHAMPS questionnaire, analyzing the self-reported frequency and duration of weekly exercise-related activities. Results: Interference effects were significantly different between PD patients and controls, with the PIGD group showing greater motor impairment under high cognitive load, primarily affecting gait, than the TD and control groups. Performance differences between groups diminished as cognitive load increased. Self-reported physical activity does not significantly moderate motor performance under DT conditions, suggesting that activity levels in this sample are insufficient to offset motor–cognitive interference. However, like group affiliation, physical activity directly influences motor performance during DT conditions, indicating that both factors independently impact motor–cognitive function in PD. Discussion: These findings suggest that DT assessments help differentiate PD motor subtypes, as group differences were minimal in ST conditions. While physical activity is associated with general improvements in motor ST and DT performance in PD and controls, the lack of a significant moderating effect from self-reported exercise-related physical activity indicates that current activity levels may not be high enough to counter motor–cognitive interference. More intensive or DT-specific exercise may be required to reduce interference effects. Future research should examine the role of structured physical activity programs, potentially incorporating DT training, to evaluate their impact on motor–cognitive interference in PD. [ABSTRACT FROM AUTHOR]

Background and objectives: The use of polymeric nanoparticles (NPs) in drug delivery systems offers the advantages of enhancing drug efficacy and minimizing side effects; Methods: In this study, L-threonine polyurethane (LTPU) NPs have been fabricated by water-in-oil-in-water emulsion and solvent evaporation using biodegradable and biocompatible LTPU. This polymer was pre-synthesized through the use of an amino acid-based chain extender, desaminotyrosyl L-threonine hexyl ester (DLTHE), where urethane bonds are formed by poly(lactic acid)-poly(ethylene glycol)-poly(lactic acid) (PLA-PEG-PLA) triblock copolymer and 1,6-hexamethylene diisocyanate (HDI). LTPU is designed to be degraded by hydrolysis and enzymatic activity due to the presence of ester bonds and peptide bonds within the polymer backbone. LTPU NPs were fabricated by water-in-oil-in-water double emulsion solvent evaporation methods; Results: The polymerization of LTPU was confirmed by 1H-NMR, 13C-NMR, and FT-IR spectroscopies. The molecular weights and polydispersity, determined with GPC, were 28,800 g/mol and 1.46, respectively. The morphology and size of NPs, characterized by DLS, FE-SEM, TEM, and confocal microscopy, showed smooth and spherical particles with diameters less than 200 nm; Conclusions: In addition, the drug loading, encapsulation efficiency, and drug release profiles, using UV-Vis spectroscopy, showed the highest encapsulation efficiency with 2.5% carboplatin and sustained release profile. [ABSTRACT FROM AUTHOR]

The incidence of right-turning pedestrian accidents is increasing in South Korea. Most of the accidents occur when a large vehicle is turning right, and the main cause of the accidents was found to be the driver's limited field of vision. After these accidents, the government implemented a series of institutional measures with the objective of preventing such accidents. However, despite the institutional arrangements in place, pedestrian accidents continue to occur. We focused on the many limitations that autonomous vehicles, like humans, can face in such situations. To address this issue, we propose a right-turn pedestrian collision avoidance system by installing a LiDAR sensor in the center of the intersection to facilitate pedestrian detection. Furthermore, the urban road environment is considered, as this provides the optimal conditions for the model to perform at its best. During this research, we collected data on right-turn accidents using the CARLA simulator and ROS interface and demonstrated the effectiveness of our approach in preventing such incidents. Our results suggest that the implementation of this method can effectively reduce the incidence of right-turn accidents in autonomous vehicles. [ABSTRACT FROM AUTHOR]

Electron beam velocity spread influences the instantaneous bandwidth of a two-stage tapered gyrotron travelling wave tube amplifier. During the velocity spreads, the electron phase-mixing induces frequency-dependent sharp gain dip in the amplifier. The changes in the magnetic field profile, circuit length, velocity spread, and the beam axial velocity cause shifting or lowering of the gain dips. An analytical expression reveals the correlation between these parameters and bandwidth.