Monitoring of local oxygen pressure in brain white matter (tip(O2)) and of local hemoglobin oxygen saturation (rS(O2)) with near-infrared spectroscopy (NIRS) are increasingly employed techniques in neurosurgical intensive care units. Using frequency-based mathematical methods, the authors sought to ascertain whether both techniques contained similar information. Twelve patients treated in the intensive care unit were included (subarachnoid hemorrhage, n = 3; traumatic brain injury, n = 9). A tip(O2) probe and an NIRS sensor were positioned over the frontal lobe with the most pathologic changes on initial computed tomography scan. The authors calculated coherence of tip(O2) and rS(O2) ts overall density distribution, its distribution per data set, and its time evolution. The authors identified a band of significantly correlated frequencies (from 0 to 1.3 x 10(3) Hz) in more than 90% of the data sets for coherence and overall density distribution. Time evolution showed slow but marked changes of significant coherence. By means of spectral analysis the authors show that tip(O2) and rS(O2)signals contain similar information, albeit using completely different registration methodologies.
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http://dx.doi.org/10.1097/00004647-200205000-00012 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
State Key Lab of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, Sun Yat-sen University, Guangzhou 510275, China.
Optical responses of twisted bilayer graphene at targeted wavelengths can be amplified by leveraging energy levels of van Hove singularities (VHS) via tuning periods of moiré superlattices. Therefore, precise control of twist angles as well as the moiré superlattices is necessary for fabricating integrated optoelectronic devices such as photodetectors and emitters. Although recent advances in twist angle control help the observation of correlated states in twisted magic-angle graphene structures, the impact of such precise control on enhanced optical absorption is still under investigation.
View Article and Find Full Text PDFFront Psychiatry
January 2025
Department of Psychiatry, Nara Medical University School of Medicine, Kashihara, Japan.
Aim: Functional neuroimaging studies have suggested that prefrontal cortex dysfunction occurs in individuals with autism spectrum disorder (ASD). Near-infrared spectroscopy (NIRS) is a noninvasive optical tool used to investigate oxygenation and hemodynamic responses in the cerebral cortex by measuring changes in oxygenated hemoglobin. Previous studies using NIRS have suggested that male children with ASD exhibit reduced hemodynamic responses in the dorsolateral prefrontal cortex; however, only a few studies examined this response in adults with ASD.
View Article and Find Full Text PDFLuminescence
January 2025
Department of Physics, IMN, Universidad de La Laguna, San Cristobal de La Laguna, Santa Cruz de Tenerife, Spain.
Er-doped BaF single crystals were investigated with two primary aims: first, to probe the infrared emissions from the I level (around 1.0 μm) under 1500-nm excitation and, second, to use the crystal to enhance the efficiency of silicon-based solar cells through upconversion mechanism. Upon excitation at 1500 nm, the upconversion emission spectrum of the Er-doped BaF single crystals, recorded in the range of 480-1080 nm, exhibited two well-structured visible bands at 538 and 650 nm, along with a strong near infrared emission at 971 nm.
View Article and Find Full Text PDFJ Biophotonics
January 2025
School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
Motor dysfunction of the upper limbs following a stroke predominantly arises from abnormal motor patterning caused by the disrupted balance of inter-cortical communication within motor-associated cortical regions. Temporal analysis offers a more precise reflection of the cortical functional state in affected patients. This study employed fNIRS to capture hemodynamic responses among 20 stroke patients and 19 healthy controls in both resting and Baduanjin task state.
View Article and Find Full Text PDFPsychother Res
January 2025
Department of Psychology, University of Haifa, Haifa, Israel.
Objective.: There is a growing consensus that interpersonal processes are key to understanding psychotherapy. How might that be reflected in the brain? Recent research proposes that inter-brain synchrony is a crucial neural component of interpersonal interaction.
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