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A Liquid Crystal Tunable Filter-Based Hyperspectral LiDAR System and Its Application on Vegetation Red Edge Detection
摘要： In this letter, a hyperspectral light detection and ranging (HSL) with 10-nm spectral resolution was designed and tested using a supercontinuum laser source. The major difference between the prototyped HSL and similar instruments was that a liquid crystal tunable ?lter (LCTF) was installed before the avalanche photodiode detector and utilized as a spectroscopic device. The design allowed continuous wavelength selection of the backscattered echoes in the time dimension. Moreover, for general accuracy evaluation of range measurement and spectral measurement, laboratory experiments for vegetation red edge detection were performed using the prototyped HSL to assess its feasibility on agriculture application. Yellow and green leaves from aloe and dracaena plants were measured by the LCTF-HSL for detecting the corresponding “red edge” position. Spectral pro?les measured by an SVC-HR-1024 spectrometer which is designed by SVC company were used as a reference to evaluate the measurements of HSL. The comparison results showed that the red edge positions extracted from the two individual measurements were similar, thus indicating that the LCTF-based high-resolution HSL was effective for this application.
关键词： red edge,liquid crystal tunable ?lter (LCTF),Hyperspectral light detection and ranging (LiDAR) (HSL)
更新于2025-09-09 09:28:46
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Identification and characterization of a core set of <scp>ROS</scp> wave‐associated transcripts involved in the systemic acquired acclimation response of Arabidopsis to excess light
摘要： Systemic acquired acclimation (SAA) plays a key role in optimizing growth and preventing damages associated with fluctuating or abrupt changes in the plant environment. To be effective, SAA has to occur at a rapid rate and depend on rapid signaling pathways that transmit signals from affected tissues to all parts of the plant. Although recent studies identified several different rapid systemic signaling pathways that could mediate SAA, very little is known about the extent of their involvement in mediating transcriptomic responses. Here we reveal that the systemic transcriptomic response of plants to excess light stress is extensive in its context and involves an early (2 minute) and transient stage of transcript expression that includes thousands of genes. This early response is dependent on the respiratory burst oxidase homolog D protein, and the function of the reactive oxygen species (ROS) wave. We further identify a core set of transcripts associated with the ROS wave and suggest that some of these transcripts are involved in linking ROS with calcium signaling. Priming of a systemic leaf to become acclimated to a particular stress during SAA involves thousands of transcripts that display a rapid and transient expression pattern driven by the ROS wave.
关键词： Arabidopsis thaliana,H2O2 signaling,systemic signaling,Reactive oxygen species (ROS) wave,Transcriptomics,light stress,MYB30,systemic acquired acclimation (SAA),WRKY
更新于2025-09-09 09:28:46
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Wirelessly Operated, Implantable Optoelectronic Probes for Optogenetics in Freely Moving Animals
摘要： Recording and interrogating brain activities using optical methods have become emerging technologies in neuroscience. Traditional tools for optogenetic stimulation in the deep brain are mostly based on implantable fibers, imposing constraints on the animal movement. Recently developed microscale light-emitting diodes (micro-LEDs), which can be wirelessly operated, serve as injectable light sources that directly interact with neural systems. Here, we exploit a wirelessly controlled, implantable system for optogenetic studies in behaving animals. Thin-film indium gallium nitride (InGaN)-based blue micro-LEDs transferred onto flexible probes are injected into the animal brain and optically activate channelrhodopsin-2 expressing neurons. A customized circuit module with a battery is employed to modulate the micro-LED, which is remotely controlled at a distance up to 50 m via 2.4-GHz radio frequency communications. The systems are implemented on freely moving mice, and demonstrate optogenetic modulation of locomotive behaviors in vivo. Moreover, independent and synchronous control of multiple animals is accomplished with the communication unit in the design circuit. The proposed system provides the potential for advanced optical neural interfaces and offers solutions to study complicated animal behaviors in neuroscience research.
关键词： optogenetics,Implantable devices,micro-light-emitting diodes (LEDs),wireless operation
更新于2025-09-09 09:28:46
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Sb <sub/>2</sub> O <sub/>3</sub> /Sb <sub/>2</sub> S <sub/>3</sub> Heterojunction Composite Thin Film Photoanode Prepared via Chemical Bath Deposition and Post-Sulfidation
摘要： Novel visible-light-driven Sb2O3/Sb2S3 photoelectrodes were synthesized via chemical bath deposition and post-sul?dation. An enhanced photocurrent density of 0.35 mA/cm2 at 1.23 V vs. RHE under simulated sunlight was achieved, compared to 0.008 mA/cm2 at 1.23 V vs. RHE for pure Sb2O3. The great improvement in the photoelectrochemical (PEC) performance bene?ts from the enhanced light absorbance and charge transfer ef?ciency attributable to the combination of Sb2S3. The Sb2O3/Sb2S3 heterojunction strategy shows potential for visible-light-driven photoelectrochemical water splitting.
关键词： heterojunction,photoelectrochemical,Sb2O3/Sb2S3,visible-light-driven,water splitting
更新于2025-09-09 09:28:46
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Impact of Overlapping Fe/TiO <sub/>2</sub> Prepared by Sol-Gel and Dip-Coating Process on CO <sub/>2</sub> Reduction
摘要： Fe-doped TiO2 (Fe/TiO2) film photocatalyst was prepared by sol-gel and dip-coating process to extend its photoresponsivity to the visible spectrum. To promote the CO2 reduction performance with the photocatalyst, some types of base materials used for coating Fe/TiO2, which were netlike glass fiber and Cu disc, were investigated. The characterization of prepared Fe/TiO2 film coated on netlike glass fiber and Cu disc was analyzed by SEM and EPMA. In addition, the CO2 reduction performance of Fe/TiO2 film coated on netlike glass disc, Cu disc, and their overlap was tested under a Xe lamp with or without ultraviolet (UV) light, respectively. The results show that the concentration of produced CO increases by Fe doping irrespective of base material used under the illumination condition with UV light as well as that without UV light. Since the electron transfer between two overlapped photocatalysts is promoted, the peak concentration of CO for the Fe/TiO2 double overlapping is approximately 1.5 times as large as the Fe/TiO2 single overlapping under the illumination condition with UV light, while the promotion ratio is approximately 1.1 times under that without UV light.
关键词： UV light,Fe-doped TiO2,visible spectrum,photocatalyst,dip-coating,sol-gel,CO2 reduction
更新于2025-09-09 09:28:46
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Daylight Spectrum Index: A New Metric to Assess the Affinity of Light Sources with Daylighting
摘要： The current scenario of colorimetry shows a wide variety of different metrics which do not converge in the assessment of the color rendering of light sources. The limitations of the Color Rendering Index have promoted the emergence of new metrics, such as the Color Quality Scale. As in the case of the previous metric, these new concepts are based on the analysis of the deviation of different color samples in a color space, contrasting the results with those obtained with a light source reference, which can vary depending on the color temperature. Within this context, the Daylight Spectrum Index is proposed. This new concept aims to determine the affinity with daylighting of electric light sources, comparing the resulting spectral power distributions of the lamps studied and that observed under natural light. The affinity of an electric light source with daylighting allows for lower energy consumption due to the better performance of human vision. The new metric proposed is evaluated following the results obtained from 80 surveys, demonstrating the usefulness of this new concept in the quanti?cation of color rendering of LED lamps and the affinity of electric light sources with daylighting.
关键词： light spectra,light sources,color rendition,colorimetry,energy savings,daylighting
更新于2025-09-04 15:30:14
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Novel blue light emitting poly(arylene ether)s under the influence of guest concentrations in host-guest systems: Synthesis, electrochemical and photophysical properties
摘要： A series of novel blue (poly-arylene ether)s polymers based on the anthracene derivatives as the guest material, and the hole transfer carbazole dervatives as the host material have been successfully synthesized by nucleophilic polycondensation. The obtained polymers exhibited high glass transition temperatures (Tg) ranging from 180 to 255 °C and decomposition temperatures (Td) ranging from 358 to 477 °C. Number average molecular weight (Mn) ranged from 3.12 × 104 to 7.20 × 104, and polydispersity indices (PDI) ranged from 1.25 to 2.10. Cyclic voltammetry investigation inform that these polymers possess LUMO energy levels ranging from ?2.29 to ?2.46 eV. In case of thin films state, all the polymers emit blue luminance with the emission maximum peaks ranging from 442 to 448 nm. The electroluminescent devices based on the these polymers with a configuration of ITO/PEDOT:PSS/polymer/TmPyPB/LiF/Al emitted blue light with CIE chromaticity coordinates of (0.15, 0.10).
关键词： Polymer Light Emitting Diodes,Ether Linkage,Blue Light Emission,Anthracene,Carbazole
更新于2025-09-04 15:30:14
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[Paper] A 3-D Display Pipeline: Capture, Factorize, and Display the Light Field of a Real 3-D Scene
摘要： Inspired by pioneering work on modern light field displays, we developed a prototype display in which three liquid crystal display (LCD) panels are stacked in front of a backlight. The stacked LCD panels constitute a set of semi-transparent layers, which modulate the out-going light rays. Even though only three layers are used, this display can emit a light field, i.e., a dense set of many multi-view images, in different viewing directions simultaneously. We established a process pipeline from capture to display of the light field of a real 3-D scene. We analyzed the amount of pop-out and motion parallax that can be presented by the display using a given light field data. We used a light field camera (Lytro Illum) and a multi-view camera (ViewPLUS ProFUSIOIN 25) to capture the light field, which was then factorized into layer representations to be displayed. We show several successful results using our prototype display.
关键词： light field,non-negative tensor factorization,image based rendering,3-D display,light field camera
更新于2025-09-04 15:30:14
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Impact of black silicon on light- and elevated temperature-induced degradation in industrial passivated emitter and rear cells
摘要： Light and elevated‐temperature induced degradation (LeTID) is currently a severe issue in passivated emitter and rear cells (PERC). In this work, we study the impact of surface texture, especially a black silicon (b‐Si) nanostructure, on LeTID in industrial p‐type mc‐Si PERC. Our results show that during standard LeTID conditions the b‐Si cells with atomic‐layer‐deposited aluminum oxide (AlOx) front surface passivation show no degradation despite the presence of a hydrogen‐rich AlOx/SiNx passivation stack on the rear. Furthermore, b‐Si solar cells passivated with silicon nitride (SiNx) on the front lose only 1.5%rel of their initial power conversion efficiency, while the acidic‐textured equivalents degrade by nearly 4%rel under the same conditions. Correspondingly, clear degradation is visible in the internal quantum efficiency (IQE) of the acidic‐textured cells, especially in the ~850 to 1100‐nm wavelength range confirming that the degradation occurs in the bulk, while the IQE remains nearly unaffected in the b‐Si cells. The observations are supported by spatially resolved photoluminescence (PL) maps, which show a clear contrast in the degradation behavior of b‐Si and acidic‐textured cells, especially in the case of SiNx front surface passivation. The PL maps also suggest that the magnitude of LeTID scales with surface area of the texture, rather than wafer thickness that was recently reported, although the b‐Si cells are slightly thinner (140 vs 165 μm). The results indicate that b‐Si has a positive impact on LeTID, and hence, benefits provided by b‐Si are not limited only to the excellent optical properties, as commonly understood.
关键词： passivated emitter and rear cells,multicrystalline silicon,light‐induced degradation,black silicon,solar cells,light‐ and elevated temperature‐induced degradation
更新于2025-09-04 15:30:14
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Application of Analytic Technique Using Green Light Parallel-Polarized Light Images in Various Skin Diseases
摘要： Ordinary photography may not fully represent patients’ skin status, but digital photography using a consistent and appropriate light-emitting diode (LED) illuminator could provide more objective and reliable images and colorimetric data. Previous studies have shown that parallel-polarized light (PPL) images taken with green LED show more significant quantitative differences, depending on the state of the skin, than those taken with white LED. This study aimed to determine the skin diseases appropriate for an analytic technique using PPL images taken with green and white LEDs.
关键词： green light,parallel-polarized light images,analytic technique,skin diseases
更新于2025-09-04 15:30:14