We propose and demonstrate a highly sensitive refractive index (RI) sensor based on a novel fiber-optic multi-mode interferometer (MMI), which is formed with a femtosecond-laser-induced in-core negative refractive index modified line in a standard single mode fiber. The proposed MMI structure is directly written with femtosecond laser in one step, which removes the splicing process needed in conventional MMI fabrication and also significantly improves the robustness. This device exhibits a high sensitivity to surrounding refractive index, with a maximum sensitivity up to 10675.9 nm/RIU at the RI range of 1.4484-1.4513. The distinct advantages of high sensitivity, compact, robust and assembly-free all-fiber structure make it attractive for real physical, chemical and biological sensing.
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http://dx.doi.org/10.1364/OE.25.029896 | DOI Listing |
Sci Rep
December 2024
Department of Breast, The First Hospital of Hunan University of Chinese Medicine, Changsha, 410007, China.
The association between the dietary inflammatory index (DII) and visual impairment remains unclear. This study aimed to investigate the relationship between the DII and non-refractive visual impairment among US populations. A cross-sectional analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2008, including dietary information and visual impairment assessment.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Guangdong Provincial Key Laboratory of Photonics Information Technology, Guangdong University of Technology, Guangzhou 510006, China.
The in situ and label-free detection of molecular information in biological cells has always been a challenging problem due to the weak Raman signal of biological molecules. The use of various resonance nanostructures has significantly advanced Surface-enhanced Raman spectroscopy (SERS) in signal enhancement in recent years. However, biological cells are often immersed in different formulations of culture medium with varying refractive indexes and are highly sensitive to the temperature of the microenvironment.
View Article and Find Full Text PDFIndian J Ophthalmol
January 2025
Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India.
Purpose: The primary objective was to evaluate the clinical response of refractory cases of fungal keratitis to topical 1% posaconazole therapy.
Methods: Prospective longitudinal non-randomized open label dual-cohort study of 70 eyes of refractory fungal keratitis, 35 were recruited as posaconazole treatment (PCZ) group for topical 1% posaconazole therapy and compared to 35 eyes on conventional antifungal therapy. Study parameters included demographic and treatment details, visual acuity, comprehensive slit-lamp biomicroscopy, clinical photography, ASOCT at recruitment and weekly (week 1, 2, 3 and 4 after treatment initiation).
Ophthalmic Physiol Opt
December 2024
Optometry and Vision Sciences Research Group, Aston University, Birmingham, UK.
Purpose: To propose a novel artificial intelligence (AI)-based virtual assistant trained on tabular clinical data that can provide decision-making support in primary eye care practice and optometry education programmes.
Method: Anonymised clinical data from 1125 complete optometric examinations (2250 eyes; 63% women, 37% men) were used to train different machine learning algorithm models to predict eye examination classification (refractive, binocular vision dysfunction, ocular disorder or any combination of these three options). After modelling, adjustment, mining and preprocessing (one-hot encoding and SMOTE techniques), 75 input (preliminary data, history, oculomotor test and ocular examinations) and three output (refractive, binocular vision status and eye disease) features were defined.
Biosens Bioelectron
December 2024
College of Information Science and Engineering, Northeastern University, Shenyang, 110819, China; Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao, 066004, China.
A novel dual-parameter optical fiber biosensor based on surface plasmon resonance (SPR) for simultaneous measurement of urea and uric acid concentrations is proposed in this paper. Based on the principle of positive and negative electric combination, ZnO nanoparticles is selected as the matrix for immobilizing urease and uricase with selective recognition ability, which can also be used as a sensitizing material to increase the refractive index detection sensitivity of SPR by 22%. Then, Nafion ion exchange membrane was introduced to wrap the urea sensing area to avoid crosstalk caused by the overlap of adjacent sensing areas.
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