In eight right-handed healthy males aged 9.6-12.9 years, changes in the frontal cerebral concentrations of oxygenated, deoxygenated, and total hemoglobin, as well as in tissue oxygenation index and cytochrome oxidase aa(3) were measured by near-infrared spectroscopy. The males were evaluated using a trail-making test with four test cycles interrupted by relax breaks. During the first cycle of this task, a significant increase in deoxygenated hemoglobin was documented in the left frontal region. In the extended course of the test, a significant increase in oxygenated and total hemoglobin was observed on both sides, indicating an increase in cerebral blood volume. However, only on the left side was an increase in deoxygenated hemoglobin documented. In children, changes in cerebral oxygenation induced by a cognitive task could be measured by near-infrared spectroscopy. In a short and extended attention task, a lateralized increase in oxygen consumption was documented by an increase in deoxygenated hemoglobin. In an extended attention task, an increase in oxygenated and total hemoglobin was recorded additionally in both frontal brain regions, indicating a compensatory increase in cerebral perfusion. Further studies are required to examine the significance of this technique in testing differences in children with neurobehavioral disabilities.
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http://dx.doi.org/10.1016/j.pediatrneurol.2003.12.010 | DOI Listing |
Neuroscience
January 2025
Kansai University of Health Sciences, Faculty of Health Sciences, Department of Physical Therapy, 2-11-1 Wakaba Sennangun Kumatori, Osaka 590-0482, Japan; Graduate School of Kansai University of Health Sciences, Graduate School of Health Sciences, 2-11-1 Wakaba Sennangun Kumatori, Osaka 590-0482, Japan.
Elderly adults may have poorer recall ability than young adults and may not fully enjoy the effects of motor imagery. To understand the age bias of the effect of motor imagery on hand dexterity, we evaluated brain activation and spinal motor nerve excitability. Brain activation was evaluated from changes in oxygenated hemoglobin concentration, while spinal motor nerve excitability was evaluated from F-waves in eight young (mean age 21.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Key Laboratory of Spectral Imaging Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119 China. Electronic address:
Non-optically active water quality parameters (NAWQPs) are essential for surface water quality assessments, although automated monitoring methods are time-consuming, include labor-intensive chemical pretreatment, and pose challenges for high spatiotemporal resolution monitoring. Advancements in spectroscopic techniques and machine learning may address these issues. We integrated ultraviolet-visible-near infrared absorption spectroscopy with physical-chemical measurements to predict total nitrogen (TN), dissolved oxygen (DO), and total phosphorus (TP) in the Yangtze River Basin, China.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Marshall Laboratory of Biomedical Engineering, International Cancer Center, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Laboratory of Evolutionary Theranostics (LET), School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen University, Shenzhen 518055, China.
The introduction of fluorescence imaging (FLI) in near-infrared II sub-channels (NIR-IIb, 1500-1700 nm) has revolutionized the ability to explore complex patho-physiological settings . Despite the transformative potentials, the development of organic NIR IIb dyes encounters considerable difficulties, and only a limited number of such fluorophores have been developed so far. This review systematically introduces design strategies of organic NIR-IIb fluorophores classified by molecular scaffolds, mainly including cyanine dyes and D-A-D small molecule dyes.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
January 2025
Department of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, U.K.
Many different types of nanoparticles have been developed for photothermal therapy (PTT), but directly comparing their efficacy as heaters and determining how they will perform when localized at depth in tissue remains complex. To choose the optimal nanoparticle for a desired hyperthermic therapy, it is vital to understand how efficiently different nanoparticles extinguish laser light and convert that energy to heat. In this paper, we apply photothermal mass conversion efficiency (η ) as a metric to compare nanoparticles of different shapes, sizes, and conversion efficiencies.
View Article and Find Full Text PDFOpt Express
January 2025
The perceived colors of silicon-on-insulator (SOI) wafers with etched Si surface layers of thickness 90 nm to 30 nm vary from turquoise to purple to golden. Measured reflectance curves spanning ultraviolet, visible, and near infrared wavelengths have an amplitude modulated oscillatory pattern. Multilayer reflectance calculations indicate the oscillatory pattern results from the 2 µm thick buried SiO layer which functions as a nearly lossless reflective Fabry-Perot etalon in the near infrared where SiO and Si are transparent.
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