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BackgroundCognitive training using virtual reality (VR) may result in motivational and playful training for patients with mild cognitive impairment and mild dementia. Fully immersive VR sets patients free from external interference and thus encourages patients with cognitive impairment to maintain selective attention. The enriched environment, which refers to a rich and stimulating environment, has a positive effect on cognitive function and mood. ObjectiveThe aim of this study was to investigate the feasibility and usability of cognitive training using fully immersive VR programs in enriched environments with physiatrists, occupational therapists (OTs), and patients with mild cognitive impairment and mild dementia. MethodsThe VR interface system consisted of a commercialized head-mounted display and a custom-made hand motion tracking module. We developed the virtual harvest and cook programs in enriched environments representing rural scenery. Physiatrists, OTs, and patients with mild cognitive impairment and mild dementia received 30 minutes of VR training to evaluate the feasibility and usability of the test for cognitive training. At the end of the test, the usability and feasibility were assessed by a self-report questionnaire based on a 7-point Likert-type scale. Response time and finger tapping were measured in patients before and after the test. ResultsParticipants included 10 physiatrists, 6 OTs, and 11 patients with mild cognitive impairment and mild dementia. The mean scores for overall satisfaction with the program were 5.75 (SD 1.00) for rehabilitation specialists and 5.64 (SD 1.43) for patients. The response time of the dominant hand in patients decreased after the single session of cognitive training using VR, but this was not statistically significant (P=.25). There was no significant change in finger tapping in either the right or left hand (P=.48 and P=.42, respectively). None of the participants reported headaches, dizziness, or any other motion sickness after the test. ConclusionsA fully immersive VR cognitive training program may be feasible and usable in patients with mild cognitive impairment and mild dementia based on the positive satisfaction and willingness to use the program reported by physiatrists, OTs, and patients. Although not statistically significant, decreased response time without a change in finger tapping rate may reflect a temporary increase in attention after the test. Additional clinical trials are needed to investigate the effect on cognitive function, mood, and physical outcomes.

Temporal and spatial tuning of the refractive index of optical thin films is desired for flat optics applications. The redistribution of mobile ions in mixed ionic-electronic conductors (MIEC) has been demonstrated to serve as a viable means for achieving optical tuning down to the nanoscale. Here we studied the dynamic range of the optical tuning achievable in the refractive index, in the MIEC oxide – PrxCe1−x O2−δ (PCO), for x = 0.1, 0.2 and 0.4, at 500 °C, by in-situ spectrophotometry. Significant increases in the modulation of both the imaginary and real optical constants in the visible and the adjacent spectra were obtained for increased doping levels. Device employing an electrochemical titration method was implemented to modulate the oxygen concentration, and thereby the optical transmission of PCO. Incorporation of a patterned top electrode allowed for the demonstration of spatial control of PCO thin film properties by in-situ video imaging of the optical switching process. The electrochemically induced optical state is shown to remain non-volatile upon quenching the device to room temperature under applied bias.

Background/Objectives: The objective of this study was to develop a novel quantitative disability assessment tool for patients with idiopathic Parkinson's disease (IPD). Methods: A total of 47 patients with IPD were recruited from two hospitals. A specialist in Rehabilitation Medicine utilized the modified Schwab and England Activities of Daily Living Scale (mSEADL) as a reference, conducting a comprehensive medical chart review and an in-depth interview. The novel-developed disability measurement was calculated as ((mSEADL during the on-state) × (time of on-state)) + ((mSEADL during the off-state) × (time of off-state))/(waking time). Additionally, the degree of disability was assessed using the Korean version of the Modified Barthel Index during the on-state. Results: Twenty-four participants (51.1%) exhibited the off-state during waking hours. In patients exhibiting an off-state, the mSEADL score was significantly lower during the off-state than during the on-state (p < 0.05). The novel-developed disability measurement demonstrated a higher correlation coefficient with the reference mSEADL (0.960) than with the K-MBI (0.808), with statistical significance (p < 0.05). Conclusions: The results demonstrated that larger IPD patients exhibited an on–off phenomenon with greater dependency during the off-state. Therefore, the on–off phenomenon should be considered when evaluating disability in patients with IPD, with methods such as the novel-developed disability measurement tool in this study. [ABSTRACT FROM AUTHOR]

Backgound: Although cognitive control is essential for efficient gait, the associations between cognitive and motor networks regarding gait in individuals with Parkinson's disease (PD) remain to be determined. Herein, we enrolled 28 PD and 28 controls to compare internetwork coupling among cognitive and motor networks and examine its relationship with single- and dual-task gait performance in PD. Methods: The dorsal attention network (DAN), left and right frontoparietal control networks (FPNs), sensorimotor network, and lateral motor network were identified using resting-state functional magnetic resonance imaging data. The time taken to complete a 10-m walk test during cognitive or physical dual-tasks in PD was calculated representing gait performance. Results: We observed that the internetwork couplings between the DAN and motor networks and between the motor networks decreased whereas those between the left FPN and DAN and motor networks increased in PD compared to controls using a permutation test. There was no significant correlation between the internetwork couplings and single- and dual-task gait performance in PD. Nevertheless, improved cognitive dual-task performance showed a positive correlation with the DAN and left FPN coupling and a negative correlation with the DAN and lateral motor network coupling in a good performance group. The opposite relationship was observed in the poor cognitive dual-task performance group. Conclusion: Our findings suggest a neural mechanism of cognitive control on gait to compensate for reduced goal-directed attention in PD who maintain cognitive dual-task performance. [ABSTRACT FROM AUTHOR]

The interaction between ambient oxygen and the metal oxide surface is central to various electrochemical devices. Solid oxide fuel cell cathodes and semiconducting metal oxide gas sensors are two prominent examples. Parallels between these two systems are highlighted in this perspective. In both cases, the presence of foreign surface species has been found to significantly alter the interactions of the metal oxides' surfaces with oxygen. On the one hand, interactions are hindered due to the presence of certain impurities, such as the degradation of fuel cell cathode by Si‐species that originate from processing or from operating environments. On the other hand, electrochemically active noble metal additives have been intentionally used to tune the sensor response of metal oxides. In the case of electrochemically active additives, the need for operando spectroscopies to elucidate the mechanism is discussed. Electronic coupling of the surface additive with the metal oxide is found to play a central role in both cases. We use these results to demonstrate that insights gained from either field can be effectively applied to the other. [ABSTRACT FROM AUTHOR]