Functional Electrochemistry: On-Nerve Assessment of Electrode Materials for Electrochemistry and Functional Neurostimulation
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PROVIDER: S-EPMC10914184 | biostudies-literature | 2024 Jan
REPOSITORIES: biostudies-literature
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Project description:BackgroundSpatial neglect is a neurocognitive disorder that affects perception, representation, and/or motor planning. Neglect dyslexia in spatial neglect after right hemisphere damage may co-occur with, or be dissociated from, other spatial neglect signs. Previous neglect dyslexia research focused on word-level stimuli and reading errors. Using single words for assessment may leave some people with neglect dyslexia undiagnosed, and assessment materials that are closer to texts read in real life may better capture neglect dyslexia.MethodThe authors tested reading in 67 right hemisphere stroke survivors with 4 types of text materials: words, phrases, an article, and a menu.ResultsAccuracy on reading the menu and article texts was significantly poorer than reading the words and phrases. The hypothesis that assessment materials with ecological validity such as reading a menu and reading an article may be more challenging than reading single words and phrases was supported.ConclusionResults suggest that neglect dyslexia assessment after stroke should include text materials comparable to those read in everyday life. Increasing the spatial extent of training materials in future research might also yield better functional generalization after right brain stroke.
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Project description:Conventional electrodes in typical photodetectors only conduct electrical signals and introduce high optical reflection, impacting the optical-to-electrical conversion efficiency. The created surface solar harvester with a multi-functional folded electrode (MFFE) realizes both a three-dimensional Schottky junction with a larger light detecting area as well as low optical reflection from 300 nm (ultra-violet light) to 1100 nm (near-infrared light) broadly without an additional anti-reflection layer. The MFFE needs silicon etching following the lithography process. The metal silver was deposited over structured silicon, completing the whole device simply. According to the experimental results, the width ratio of the bottom side to the top side in MFFE was 15.75, and it showed an optical reflection of 5-7% within the major solar spectrum of AM1.5G by the gradient refractive index effect and the multi-scattering phenomenon simultaneously. While the perovskite materials were deposited over the MFFE structure of the solar harvester, the three-dimensional electrode with lower optical reflection benefitted the perovskite solar cell with a larger detecting area and an additional anti-reflection function to absorb solar energy more efficiently. In this concept, because of the thin stacked film in the perovskite solar cell, the solar energy could be harvested by the prepared Schottky junction of the solar harvester again, except for the optical absorption of the perovskite materials. Moreover, the perovskite materials deposited over the MFFE structure could not absorb near-infrared (NIR) energies to become transparent. The NIR light could be harvested by the light detecting junction of the solar harvester to generate effective photocurrent output additionally for extending the detection capability of perovskite solar cell further. In this work, the concept of integration of a conventional perovskite solar cell with a silicon-based solar harvester having an MFFE structure was proposed and is expected to harvest broadband light energies under low optical reflection and enhance the solar energy conversion efficiency.
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