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Hydrogel optical fibers are utilized for continuous glucose sensing in real time. The hydrogel fibers consist of poly(acrylamide-co-poly(ethylene glycol) diacrylate) cores functionalized with phenylboronic acid. The complexation of the phenylboronic acid and cis-diol groups of glucose enables reversible changes of the hydrogel fiber diameter. The analyses of light propagation loss allow for quantitative glucose measurements within the physiological range.

Current 2D windshield head-up displays can lead to driver distractions due to a shift of gaze from the road towards a small area of the windshield. Customizable mixed reality real-time head-up displays can increase safety in transportation due to the holographic road obstacles being aligned with the road scene. Based on accelerated parallel processing algorithms, a 4K spatial light modulator, virtual Gabor lenses and a He-Ne laser, 3D holographic road signs appear within 1.15 seconds in the driver’s gaze on the road.

Identifying road obstacles hidden from the driver's field of view can ensure road safety in transportation. Current driver assistance systems such as 2D head‐up displays are limited to the projection area on the windshield of the car. An augmented reality holographic point cloud video projection system is developed to display objects aligned with real‐life objects in size and distance within the driver's field of view. Light Detection and Ranging (LiDAR) point cloud data collected with a 3D laser scanner is transformed into layered 3D replay field objects consisting of 400 k points. GPU‐accelerated computing generated real‐time holograms 16.6 times faster than the CPU processing time. The holographic projections are obtained with a Spatial Light Modulator (SLM) (3840×2160 px) and virtual Fresnel lenses, which enlarged the driver's eye box to 25 mm × 36 mm. Real‐time scanned road obstacles from different perspectives provide the driver a full view of risk factors such as generated depth in 3D mode and the ability to project any scanned object from different angles in 360°. The 3D holographic projection technology allows for maintaining the driver's focus on the road instead of the windshield and enables assistance by projecting road obstacles hidden from the driver's field of view. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been a rising interest in utilizing functionalized porous polymers for sensor applications. By incorporating functional groups into nanostructured materials like hydrogels, nanosheets, and nanopores, exciting new opportunities have emerged for biomarker detection. The ability of functionalized polymers to undergo physical changes and deformations makes them perfect for modulating optical signals. This chemical mechanism enables the creation of biocompatible sensors for in situ biomarker measurement. Here a comprehensive overview of the current publication trends is provided in functionalized polymers, encompassing functional groups that can induce measurable physical deformations. It explores various materials categorized based on their detection targets, which include proteins, carbohydrates, ions, and deoxyribonucleic acid. As such, this work serves as a valuable reference for the development of functionalized polymer‐based sensors. [ABSTRACT FROM AUTHOR]

Inspection of pipeline infrastructure is an essential part of pipeline integrity management to prevent from leakage and flow reduction is of great importance in water, gas, and oil distribution. However, current methods are limited in low resolution and low accuracy that fail to 3D reconstructions of pipelines. In this work, a theoretical laser propagation model based on a free-form laser profilometry method is established, and a fully functional laser system that incorporates a conic mirror within an integrated optical system containing all the elements necessary to retrieve the displacement information. The developed optical device exhibit high resolution, high accuracy, and high acquisition speed comparing with current technologies. Furthermore, the device can be completely sealed to be protected from the pipeline environment. This work paves the path towards autonomous laser scanners for underwater pipeline inspection. [ABSTRACT FROM AUTHOR]

Abstract: Dynamic structural coloration in Tmesisternus isabellae beetle elytra is a unique example of Bragg stack‐based wavelength tuning in response to external stimuli. The underlying principles could guide the design of quantitative optical stimuli‐responsive polymers. Existing nanofabrication techniques to create such materials are costly, time‐consuming, and require high expertise. This study reports a nanofabrication method to produce slanted Bragg stack structures in poly(acrylamide‐co‐poly(ethylene glycol) diacrylate) hydrogel films by combining laser interference lithography and silver halide chemistry in a cost‐effective and rapid process (≈10 min). The Bragg stacks consist of silver bromide nanocrystal multilayers having a lattice spacing of ≈200 nm. Upon broadband light illumination, the Bragg stacks diffract a narrow‐band peak at 520 nm at ≈10° with respect to the normal incidence. The lattice spacing of the hydrogel films can be modulated by external stimuli to shift the Bragg peak for dynamic quantitative measurements. To demonstrate the utility of this method, the Bragg stacks are functionalized with phenylboronic acid molecules. Bragg peak shift analysis allows reversible glucose sensing within a physiological dynamic range (0.0–20.0 mmol L−1) having a sensitivity of 0.2 mmol L−1. The developed Bragg stacks may have application in portable, wearable, and implantable real‐time medical diagnostics at point‐of‐care settings. [ABSTRACT FROM AUTHOR]