A simple and compact fiber optic sensor based on a two-core fiber is demonstrated for high-performance measurements of refractive indices (RI) of liquids. In order to demonstrate the suitability of the proposed sensor to perform high-sensitivity sensing in a variety of applications, the sensor has been used to measure the RI of binary liquid mixtures. Such measurements can accurately determine the salinity of salt water solutions, and detect the water content of adulterated alcoholic beverages. The largest sensitivity of the RI sensor that has been experimentally demonstrated is 3,119 nm per Refractive Index Units (RIU) for the RI range from 1.3160 to 1.3943. On the other hand, our results suggest that the sensitivity can be enhanced up to 3485.67 nm/RIU approximately for the same RI range.
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http://dx.doi.org/10.3390/s131014200 | DOI Listing |
Neuro Oncol
January 2025
Department of Neurology, Division of Infectious Diseases, Washington University School of Medicine, St. Louis MO 63110 USA.
Background: The intestinal microbiota regulates normal brain physiology and the pathogenesis of several neurological disorders. While prior studies suggested that this regulation operates through immune cells, the underlying mechanisms remain unclear. Leveraging two well characterized murine models of low-grade glioma (LGG) occurring in the setting of the neurofibromatosis type 1 (NF1) cancer predisposition syndrome, we sought to determine the impact of the gut microbiome on optic glioma progression.
View Article and Find Full Text PDFCureus
December 2024
Cornea and Refractive Surgery, Al-Shifa Trust Eye Hospital, Rawalpindi, PAK.
Background: Glaucoma, particularly open-angle glaucoma (OAG), is a leading cause of irreversible blindness, associated with optic nerve damage, retinal ganglion cell death, and visual field defects. Corneal biomechanical properties and cellular components, such as corneal nerve and keratocyte densities assessed by in vivo confocal microscopy (IVCM), may serve as biomarkers for glaucoma progression. This study aimed to explore the relationship between corneal nerve parameters, keratocyte density, and optical coherence tomography (OCT)-derived retinal nerve fiber layer (RNFL) thickness in primary open-angle glaucoma (POAG) patients and controls.
View Article and Find Full Text PDFAnal Chem
January 2025
School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, Liaoning 116024, China.
A highly sensitive trace gas sensing system based on carbon black absorption enhanced photoacoustic (PA) spectroscopy (PAS) is reported. A carbon black sheet and a fiber-optic cantilever microphone (FOCM) are integrated to form a fiber-optic cantilever spectrophone (FOCS). The gas concentration is obtained by measuring the acoustic wave amplitude generated by the carbon black sheet, which absorbs the laser passing through the interest gas.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
January 2025
Department of Ophthalmology, Ankara Bilkent City Hospital, University of Health Sciences, Ankara, Turkey.
Purpose: In this study, it was planned to compare the macular ganglion cell analysis (GCA) and peripapillary retinal nerve fiber layer (pRNFL) of the patients with preperimetric glaucoma (PPG), early stage glaucoma (EG) and the control group.
Methods: This retrospective study included a total of 103 eyes: 38 from EG patients, 30 from PPG patients, and 35 from healthy individuals at Ankara Bilkent City Hospital Glaucoma Unit between January 2018 and September 2021. Eyes were categorized into control, PPG, and EG groups based on visual field (VF) classification.
Exp Neurol
January 2025
Brain and Mind Research Institute, Department of Biology, University of Ottawa, Ottawa, Ontario, Canada. Electronic address:
Spasticity is a common comorbidity of spinal cord injury (SCI), disrupting motor function and resulting in significant discomfort. While elements of post-SCI spasticity can be assessed using pre-clinical SCI models, the robust measurement of spasticity severity can be difficult due to its periodic and spontaneous appearance. Electrical stimulation of sensory afferents can elicit spasticity-associated motor responses, such as spasms; however, placing surface electrodes on the hindlimbs of awake animals can induce stress or encumbrance that could influence the expression of behaviour.
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