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Fringe projection profilometry (FPP) based on structured light is widely used for three-dimensional (3D) shape measurement due to its non-contact nature and high accuracy. However, in practical measurement scenarios, the surface reflectivity of objects varies significantly, leading to a mix of specular and diffuse reflections. This results in the coexistence of underexposed and overexposed areas, which remains a challenging issue in FPP. To address this problem, a dual-strategy-guided two-dimensional (2D) wavelet transform is proposed for high dynamic range (HDR) 3D shape measurement. The proposed method introduces two natural and intuitive strategies derived from the wavelet function expressions and the spectral intensity (energy) distributions to guide the local rotation of the wavelet spectrum for fringe analysis. Additionally, the measurement system employs one projector (single projection) and one camera (single shot) for phase calculation. Simulations and experiments have been conducted to verify the feasibility of the proposed method. In the experimental evaluation, the standard plane and different HDR scenes were measured for quantitative analysis. A comparison of the results with other methods was also performed. The results demonstrated that the proposed method provides what we believe to be a novel solution for single-exposure HDR 3D shape measurement.
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http://dx.doi.org/10.1364/OE.557918 | DOI Listing |
JAMA Neurol
September 2025
Department of Radiology, University of Washington, Seattle.
Importance: Recent longitudinal studies in patients with unruptured intracranial aneurysms (UIAs) suggested that aneurysm wall enhancement (AWE) on magnetic resonance imaging (MRI) predicts growth and rupture. However, because these studies were limited by small sample size and short follow-up duration, it remains unclear whether this radiological biomarker has predictive value for UIA instability.
Objective: To determine the 4-year risk of instability of UIAs with AWE and investigate whether AWE is an independent predictor of UIA instability.
ACS Chem Neurosci
September 2025
Chemical and Biomolecular Engineering Dept, University of California, Los Angeles, Los Angeles, California 90095, United States.
Simulations in three dimensions and time provide guidance on implantable, electroenzymatic glutamate sensor design; relative placement in planar sensor arrays; feasibility of sensing synaptic release events; and interpretation of sensor data. Electroenzymatic sensors based on the immobilization of oxidases on microelectrodes have proven valuable for the monitoring of neurotransmitter signaling in deep brain structures; however, the complex extracellular milieu featuring slow diffusive mass transport makes rational sensor design and data interpretation challenging. Simulations show that miniaturization of the disk-shaped device size below a radius of ∼25 μm improves sensitivity, spatial resolution, and the accuracy of glutamate concentration measurements based on calibration factors determined .
View Article and Find Full Text PDFEnviron Toxicol Chem
September 2025
Statistical Ecotoxicology, University of Bayreuth, Bayreuth, Germany.
Several micro- and nanoplastic particle (MNP) traits, like polymer type, size, and shape, have been shown to influence MNP toxicity. However, the direction and strength of these moderating effects are often unclear, and generalizations from single studies are challenging to establish. Meta-analyses increase generalizability and derive more accurate and precise effect size estimates by combining measurements from published studies.
View Article and Find Full Text PDFJ Chem Phys
September 2025
Fakultät Physik, Technische Universität Dortmund, D-44221 Dortmund, Germany.
The dynamics of the different constituents of the ionic liquid 1-hexyl-3-methylimidazolium chloride (HmimCl) is investigated using nuclear magnetic resonance including chlorine relaxometry, line shape analysis, and proton-detected diffusometry, as well as frequency-dependent shear mechanical measurements. This combination of techniques is useful to probe the individual motions of the anions and the cations, and the sample's overall flow response. The 35Cl- dynamics appears to be close to the structural (or α-) relaxation as seen by rheology.
View Article and Find Full Text PDFJ Chem Phys
September 2025
Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang Province 310027, China.
Sum-frequency generation vibrational spectroscopy (SFG-VS) has been well-established as a unique spectroscopic probe to interrogate the structure, interaction, and dynamics of molecular interfaces, with sub-monolayer sensitivity and broad applications. Sub-1 cm-1 High-Resolution Broadband SFG-VS (HR-BB-SFG-VS) has shown advantages with high spectral resolution and accurate spectral line shape. However, due to the lower peak intensity for the long picosecond pulse used in achieving sub-wavenumber resolution in the HR-BB-SFG-VS measurement, only molecular interfaces with relatively strong signal have been studied.
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