bluuebunny/crossref_metadata_2025 huggingface dataset:
Compressive Learning Holography with LPTNet
Authors: Kravets Vladislav , Stern Adrian
Published: September 2024

Learned compressive sensing involves data-driven methods for both designing the sensing mechanism and reconstructing the signal. Here we describe a learned compressive holography method utilizing our recently introduced LPTNet.
Polarized microscopy based on liquid crystals and a polarization camera: new tools for studying oocytes
Authors: Restrepo-Martínez Alejandro , Alcalde Juan José , Betancur Giovanni Restrepo
Published: September 2024

A strategy combining liquid crystal retarders and a polarization camera with an optical microscope was developed. Results show of the meiotic spindle oocyte, indicating stage of maturation.
Damping analysis of optical fiber inverted pendulum seismometer with rubber ring
Authors: Zhang Wentao , Huang Yiqian , Huang Wenzhu
Published: September 2024

Using a rubber ring as the damping element, the sensitivity of the optical fiber inverted pendulum seismometer increases from 1250.3 rad/g to 1715.7 rad/g, along with effective mitigation of the resonance peak.
Design and fabrication of wider angle field of view hybrid DOEs for a compact imaging optics
Authors: Rhee Hyug-Gyo , Hoang Anh Nguyen Nu , Ghim Young-Sik
Published: September 2024

Hybrid DOEs, which are diffraction pattern arrays fabricated on curved refractive optical elements, have the ability to widen the field of view angle, and improve optical performance and make a compat imaging optics, by combining refraction and diffraction. However, manufacturing a high resolution diffraction pattern array is challenging. We provides a method to manufacture hybrid DOEs with wider field of view and superior performance in both diffraction efficiency and resolution.
Random Illumination Microscopy using a few light grid illuminations
Authors: Barbault Pierre , Idier Jérôme , Allain Marc , Mangeat Thomas , Labouesse Simon , Sentenac Anne
Published: September 2024

Random Illumination Microscopy (RIM) usually forms a super-resolved reconstruction of the sample from the statistics of hundreds of images obtained under speckled illuminations. We show that RIM approach is also effective when a few specific light grids are used for illuminating the sample. This combination improves the temporal resolution of RIM while keeping a good robustness to illumination distortion.
Trace Determination of Cardiac Troponin I Using a Label-Free Fiber Optical Localized Surface Plasmon Resonance Biosensors
Authors: Chiang Chang-Yue , Chen Chien-Hsing , Wang Chien-Tsung , Wu Chin-Wei , Chiang Hsing-Yu
Published: September 2024

This work proposes a carboxyl-graphene-oxide-based fiber optic localized surface plasmon resonance biosensor which employed anti-Cardiac Troponin I (anti-cTnI) as the recognition element to detect the cTnI-protein in 10 min with a limit of detection (LOD) of 5.8 pM, which meets the acceptable LOD for clinical testing of 0.04 ng/mL.
Spatiotemporal digital holography microscopy fringes addresses new challenges in biological microfluidic imaging
Authors: Ferraro Pietro , Wang Zhe , Bianco Vittorio , Maffettone Pier Luca
Published: September 2024

Space-Time Digital Holography (STDH) enables high-resolution biological imaging by reassembling holographic interference fringes. For imaging the flowing cells within microfluidic channel, STDH breaks through depth of focus limits and smartly adapts to microfluidic speed.
Effect of Dye Concentration on the Spatial Coherence Measured by the Use of a Fresnel Zone Plate
Authors: Han M. , Na J. , Jung H. , Jeong Y.
Published: September 2024

A random laser was generated by irradiating a medium containing Rhodamine 6G (Rh6G) as the gain material and TiO2 as the scattering material with a frequency-doube Nd:YAG laser. The random laser light was focused by a Fresnel zone plate (FZP) and the size of the laser beam at the focal plane was measured to determine the relationship between the concentration of the gain material and the degree of coherence of the beam at the focal plane. As the concentration of the gain medium increased from 2.1 mM to 6.3 mM, the size of the beam focused at the focal plane tended to increase linearly by approximately 25%.
Configuration simplification and data reduction in a DAS system for monitoring large infrastructures
Authors: Lu Xin , Krebber Katerina
Published: September 2024

The distributed acoustic sensor based on an imbalanced Mach-Zehnder interferometer with a 3×3 coupler is simplified by using a balanced detector instead of three identical photodetectors. The obtained data is reduced by two third accordingly.
Laser Tomography Error Analysis for Laser Tomography Adaptive Optics System
Authors: Han S. G. , Joo J. Y. , Lee C. , Lee J. H.
Published: September 2024

LTAO (Laser Tomography Adaptive Optics), there are errors occur from adaptive optics and those due to laser tomography. This paper focuses on the analysis of errors under various operational conditions in laser tomography.
Imaging thermal gradients on a Li-ion battery cell during operation using frequency-domain phosphor thermometry
Authors: Bonilla Joel Lopez , Graichen Henrik-Christian , Beyrau Frank , Boye Gunar , Fond Benoit
Published: September 2024

Phosphor thermometry is applied on a mechanically loaded Li-ion pouch cell battery during operation. Using an optimised frequency domain method. Temperature images were obtained with a precision better than 0.1°C, revealing thermal patterns on the battery during charging and discharging.
High-speed 1-D Raman scattering measurement in transient hydrogen jets issued by a single-hole injector
Authors: Wu Bin , Wu Hao , Ben Houidi Moez , Sharma Priybrat , Cenker Emre , AlRamadan Abdullah S. , Roberts William L. , Magnotti Gaetano
Published: September 2024

Quantitative 1-D measurement of H2 mole fraction in transient jets is reported. By using the pulse-burst laser along with the EMCCD cameras operated in subframe burst gating mode, repetition rate of 50 kHz is achieved.
Temperature Dependent Determination of the S-Branch N2-H2O Broadening Coefficient
Authors: Misoi Henry , Hölzer Jonas I. , Seeger Thomas
Published: September 2024

The S-branch N2-H2O Raman broadening coefficients were determined from time resolved RCARS experiments up to 1900 K. Use of these linewidths for combustion diagnostics are expected to improve accuracy of temperature and mixture composition determination.
Photon-counting Fluorescence Imaging of Tobacco Cultured Cells using Transport of Intensity Equation
Authors: Matsuda Shiori , Shoda Marin , Yoneda Naru , Kumar Manoj , Matoba Osamu
Published: September 2024

In this paper, a three-dimensional fluorescent imaging using the transport of intensity equation using photon-counting image sensor is investigated by applying it to tobacco cultured cells. Experimental results showed that numerical refocusing is implemented when average number of photons per pixel is 26.
Optical Characterization of Thin Films from Transmission Data using Deep Learning
Authors: Ballester Manuel , Würsch Christoph , Marquez Emilio , Willomitzer Florian , Katsaggelos A. K.
Published: September 2024

We present a novel Deep Learning technique based on a CNN-LSTM architecture that directly performs the optical characterization of thin-film materials from their UV-VIS-IR transmission spectra.
Holographic Generation of a Cylindrical Vector Beam at the Tip of a Few-Mode Fiber
Authors: Cifuentes Angel , Varga Miguel , Molina-Terriza Gabriel
Published: September 2024

Controlling light at the tip of a multimode fiber holds great potential for sensing applications. Here, we present how by measuring the transmission matrix, we may produce a cylindrical vector beam at the fiber tip.
Non-Invasive and Noise-Robust Confocal Wavefront Shaping
Authors: Aizik Dror , Levin Anat
Published: September 2024

We use a double modulation of both excitation and emission light to correct aberration and image through thick scattering tissue. The approach is noise robust and successfully images weak fluorescent neurons inside brain tissue.
Full-Field OCT Assisted by Woofer-Tweeter Sensorless AO Approach for Large Field-of-View High-Resolution Clinical Retinal Imaging
Authors: Callet Clémentine , Bertrand Maxime , Cai Yao , Paques Michel , Grieve Kate , Mecê Pedro
Published: September 2024

Full Field OCT assisted by a plug’n’play woofer-tweeter sensorless AO approach enables large FOV high-resolution in vivo retinal imaging with a robust clinical-adapted system, paving the way towards new studies on patients.
High Refresh Rate Display Integrated with Adaptive Optics Retinal Imaging and Eye-tracking
Authors: Moon Benjamin , Linebach Glory , Yang Angelina , Jenks Samantha K. , Rucci Michele , Poletti Martina , Rolland Jannick P.
Published: September 2024

By integrating an external display operating at 360 Hz with an Adaptive Optics Scanning Laser Ophthalmoscope for human foveal imaging, we demonstrate color stimulus delivery at high spatial and temporal resolution with sub-arcminute eye-tracking uncertainty.
Hybrid Scanning Lensless Imaging by Diffractive Neural Field
Authors: Liu Yifei , Song Weizhi , Zhou You , Xiong Bo , Cao Xun
Published: September 2024

We report a lensless imaging strategy that achieves pixel-super-resolution and high-accuracy reconstruction by employing hybrid scanning and self-supervised learning.
Fringe pattern analysis using deep learning and physical priors
Authors: Yin Wei , Feng Shijie
Published: September 2024

We propose a deep-learning-based fringe pattern analysis method that employs physical priors. It can achieve accurate and efficient single-shot phase reconstruction and exhibits strong generalization capability to unseen samples.
Photon Transport Through the Adult Human Head
Authors: Gradauskas Vytautas , Radford Jack , Mitchell Kevin J. , Nerenberg Samuel , Starshynov Ilya , Faccio Daniele
Published: September 2024

Transmitting photons through an adult human head could enable non-invasive imaging deep inside the brain. We present numerical simulations and experimental measurements of photons transmitted diametrically through an adult human head.
Noninvasive Phase Imaging through Dynamically Scattering Media with Temporal Averaging
Authors: Matsuda Naoki , Tanida Jun , Naruse Makoto , Horisaki Ryoichi
Published: September 2024

We propose and demonstrate a method for noninvasive imaging of complex amplitude objects hidden behind dynamically scattering media. This method integrates a temporal averaging process and phase retrieval with a variable coded aperture.
Intelligent Quantum Sensing with Computational Neuromorphic Imaging
Authors: Wang Chutian , Gupta Madhav , Chu Zhiqin , Lam Edmund Y.
Published: September 2024

This work presents a solution that leverages the synergy of diamond quantum sensing and computational neuromorphic imaging, which brings high precision and a significant computation time reduction. It gives impetus to the advancement of more intelligent quantum sensing and computing capacity.
Surpassing the Wavefront Sensor Dynamic Range with Neuromorphic Temporal Diversity Measurements
Authors: Wang Chutian , Zhu Shuo , Zhang Pei , Lam Edmund Y.
Published: September 2024

We demonstrate the utilization of the computational neuromorphic imaging paradigm to acquire temporal diversity measurements, which proves advantageous in over-coming the dynamic range limitations of Shack-Hartmann wavefront sensors for ultra-fast large-gradient turbulence diagnosis.
Single-pixel-cameras under Photon Noise: which Gain (or Loss) as compared to Point-scanning, for Hadamard and Cosine Positive Modulation?
Authors: Scotté Camille , Galland Frédéric , Rigneault Hervé
Published: September 2024

We theoretically, numerically and experimentally assess the signal-to-noise ratio of some classes of single-pixel cameras, under Poisson noise. This leads to decision rules for when and how to use single-pixel cameras instead of point-scanning.
Differentiable chief-ray tracing simulator for coded-aperture spectral imaging
Authors: Paillet L. , Rouxel A. , Carfantan H. , Monmayrant A. , Lacroix S.
Published: September 2024

We introduce an end-to-end differentiable simulation framework for designing Coded-Aperture Snapshot Spectral Imagers (CASSI) and exploring acquisition strategies. By leveraging automatic differentiation, we dimension the optical system and optimize the coded aperture, enhancing imaging quality and facilitating effective co-design of the instrument.
Limitations of Hyperspectral Imaging from RGB Images: A Data Perspective
Authors: Fu Qiang , Souza Matheus , Choi Eunsue , Shin Suhyun , Baek Seung-Hwan , Heidrich Wolfgang
Published: September 2024

Recent progress in spectral reconstruction from RGB images with deep learning seems promising for snapshot hyperspectral imaging. However, we show that significant limitations do exist arising from the lack of diversity in the prevailing datasets.
Permutation Transient Attention Encoder for None-Line-of-Sight Imaging
Authors: Yue Wenjie , Chen Xiaxu , Liu Gangping , Wang Chutian , Lam Edmund Y. , Ke Jun
Published: September 2024

This paper introduces Permutation Transient Attention Encoders as a novel and efficient approach for NLOS reconstruction. Our method, utilizing Transient Attention Blocks and Permute-MLP, enhances transient feature extraction and offers more discrimi-native feature representations than existing approaches.
Twin Bessel Beams for Depth-Resolved Microscopy
Authors: Dong Xin , Shi Minghui , He Hongsen , Wong Kenneth Kin-Yip
Published: September 2024

We demonstrated twin Bessel beams with a z-to-x linear mapping relationship with R2 = 0.9976 in a range of 55 μm, improved by 72%, which potentially provides ability to resolve the depth in volumetric imaging.
ICE-TIDE: Implicit Cryo-ET Imaging and Deformation Estimation
Authors: Debarnot Valentin , Kishore Vinith , Righetto Ricardo D. , Dokmanić Ivan
Published: September 2024

We present ICE-TIDE, a method for cryogenic electron tomography (cryo-ET) that simultaneously aligns observations and reconstructs a high-resolution volume. The alignment of tilt series in cryo-ET is a major problem limiting the resolution of reconstructions. ICE-TIDE relies on an efficient coordinate-based implicit neural representation of the volume which enables it to directly parameterize deformations and align the projections. Furthermore, the implicit network acts as an effective regularizer, allowing for high-quality reconstruction at low signal-to-noise ratios as well as partially restoring the missing wedge information. This document is based on the preprint [1].
a
Metalens-based snapshot ptychography
Authors: Wang Xiao , Chen Ni , Wang Chengyu , Froech Johannes , Majumdar Arka , Brady David J.
Published: September 2024

We demonstrate a wavefront camera using a metalens. The metalens consists of a 5 by 5 array of overlapping focal apertures. We use a hybrid neural phase retrieval algorithm to image remote complex valued fields.
Computational correction of scanner non-linearity in 3D microscopy
Authors: Zhukova Lena , Artigas Roger , Carles Guillem
Published: September 2024

Optical profilometers use axial scanning to measure object heights, and non-linear movement of the scanner yields measurement errors. We show a computational method to correct for non-linearity errors, thereby increasing measurement precision without added components.
Effects of Intraocular Straylight on Temporal Contrast Sensitivity
Authors: Casado Pilar , Collados Victoria , Avila Francisco , Ares Jorge
Published: September 2024

This research evaluated temporal contrast sensitivity in a young population at different levels of straylight. The results showed an improvement in temporal contrast sensitivity in the presence of a glare source.
Design of narrowband mid-infrared metamaterial perfect absorbers (MPAs) based on nanoscale cross-shaped resonators
Authors: Chabbar S. , Beaudin G. , Therrien H. , Charette P. G.
Published: September 2024

Metamaterial perfect absorbers (MPAs) are subwavelength structures offering powerful light/matter interaction characteristics. This technology could pave the way for cost-effective and compact hyperspectral MID-IR filters, making the "spectral fingerprint region" more accessible for atmospheric sensing.
Development of a Hyperspectral System for real-time high throughput Bioprocess Monitoring
Authors: Mc Girr Padraig , Hill Breandan , Pollard Robert
Published: September 2024

Integrating nanophotonic sensors into the bioprocessing industry requires capturing spectral information on multiplexed assays. Using hyperspectral imaging, the spatial performance of these sensors can be characterized to determine their suitability for multiplexed biological measurements.
Jacobian Control Surfaces
Authors: Locher Maik , Eaglesham Ewan , Courtial Johannes
Published: September 2024

By controlling the Jacobian of a surface, we propose an improved compact view rotator aimed to aid in the treatment of torsional diplopia. Theoretical ray trace simulations are used to demonstrate the feasibility.
Silicon-Based 3-D Imaging with Terahertz Light-Field
Authors: Sadkaoui Hamadi , Conde Miguel Heredia , Andree Marcel , Prabhu Arjith Chandra , Kutaish Abdulraouf , Hamzeh Ehsan , Pfeiffer Ullrich R.
Published: September 2024

Terahertz (THz) light-field imaging offers a solution for material identification and imaging of opaque objects. This paper explores THz techniques, including coherence-based approaches and light-field methods, showcasing experimental setups and results.
Rotation Aperture Synthesis for Flat and Conformal Imaging
Authors: McAvenue Andrew S. , Carles Guillem , Harvey Andrew R.
Published: September 2024

We present proof-of-concept demonstration of high-resolution aperture-synthetic imaging that enables high-resolution imaging from flat camera modules. The order-of-magnitude reduction in the depth of camera modules has potential applications ranging from mobile-phone cameras to remote sensing from space.
Hybrid antiresonant negative-curvature optical fibers: theoretical analysis and sensing application
Authors: Karmakar Dipanjan , Dhar Anirban , Jain Deepak
Published: September 2024

In this paper we developed the understanding of a guidance mechanism of hybrid antiresonant negative-curvature fiber. We elucidated how the loss and cutoff wavelengths of core-guided modes depend on the lattice tube thickness and diameter for this fiber. We also derived an approximate expression to calculate the cutoff wavelengths for this hybrid antiresonant negative-curvature (core having higher refractive index than cladding) fiber. Finally, we explored the application of hybrid antiresonant fiber, proving its superior sensing capabilities compared to conventional hollow-core antiresonant fiber.
Non-Abelian braiding in three-fold degenerate subspace and the acceleration
Authors: Liu Hongzhi , Huang Jiayi , Han Zhiwei , Liang Jiahao , Chen Ziyuan , Fu Zhaoxin , He Zerui , Ming Yue , Lv Qingxian , Du Yanxiong
Published: September 2024

Non-Abelian braiding operations of quantum states have attracted substantial attention due to their great potentials for realizing topological quantum computations. The adiabatic version of quantum braiding is robust against systematic errors, yet will suffer from decoherence and dephasing effects due to a long evolution time. In this paper, we propose to realize the braiding process in a three-fold degenerate subspace of a seven-level system, where the non-Abelian effect can be detected by changing the orders of the braiding. We accelerate the adiabatic control through adding auxiliary coupling terms according to a shortcut to adiabatic theory for the non-Abelian case. Furthermore, by generalizing the parallel adiabatic passages, adiabatic control can be accelerated through only reshaping the original control waveforms and the effective pulses area will be significantly reduced. Therefore, the proposed schemes may provide an experimentally feasible way to investigate the non-Abelian braiding in atomic systems and the waveguide systems.
SUPER excitation of quantum emitters is a multi-photon process
Authors: Vannucci Luca , Gregersen Niels
Published: September 2024

The swing-up of quantum emitter population (SUPER) scheme allows to populate the excited state of a quantum emitter with near-unity fidelity using two red-detuned laser pulses. Its off-resonant yet fully coherent nature has attracted significant interest in quantum photonics as a valuable tool for preparing single-photon sources in their excited state on demand while simultaneously ensuring straightforward spectral filtering of the laser. However, the physical understanding of this mechanism in terms of energy exchange between the electromagnetic field and the emitter is still lacking. Here, we present a fully quantized model of the swing-up excitation and demonstrate that it is in fact a multi-photon process, where one of the modes loses two or more photons while the other gains at least one. Our findings provide an unexpected physical interpretation of the SUPER scheme and unveil a new non-linear interaction between single emitters and multiple field modes.
Quantum ghost imaging microscopy depth-of-field study
Authors: Davenport Dominique , Eshun Audrey , Demory Brandon , Kiannejad Shervin , Mos Paul , Lin Yang , Wayne Michael , Jeppson Sam , Wilson Ashleigh , Bond Tiziana , Rushford Mike , Boley Charles , Bruschini Claudio , Charbon Edoardo , Laurence Ted A.
Published: September 2024

Quantum ghost imaging approaches have been proposed to enhance biological microscopy, for example, using 2D visible detectors to provide IR images or providing additional dimensions of spatial or spectral information. Toward the goal of making such imaging schemes practical, we compare image quality and depth-of-field between traditional images and ghost images at the same excitation levels. We measure how image quality and depth-of-field depend on the parameters of the entangled light produced using type-I spontaneous parametric down-conversion (SPDC). We use a pair of time-synchronized, photon-timing single-photon avalanche diode (SPAD) array detectors to capture two distinct microscope imaging paths simultaneously on a photon-pair-by-photon-pair basis: one in a traditional imaging pathway and the other a quantum ghost imaging pathway. We calculate the depth-of-field, resolution, contrast, and signal-to-noise ratio (SNR) through the parameter space of a β-Barium Borate (BBO) type-I bulk non-linear crystal length and angle. Our results provide a basis for choosing parameters for quantum ghost imaging with type-I SPDC sources.
Femtosecond laser-induced black silicon: a dual application in photodetection and surface-enhanced Raman scattering
Authors: Wang Xuan , Zhao Bing , Nivas Jijil , Zhao Xiaona , Du Wenhan , Amoruso Salvatore
Published: September 2024

A multifunctional structured silicon with enhanced optical and photoelectric properties has been processed by femtosecond (fs) laser in ambient air. The structured surface decorated with Au nanoparticles (NPs) exhibits excellent infrared absorption properties related to localized surface plasmon resonance (LSPR) coupled to microstructures. Over 75% absorption is achieved at 1550 nm, which is three orders of magnitude higher than that of unprocessed Si. The absorption enhancement results in increased photocurrent response in n + -n junction diodes, exhibiting a responsivity of 125 mA/W and an external quantum efficiency (EQE) of 10% at 1550 nm, for a bias voltage of 10 V. Moreover, the structured Si is also tested as a surface-enhanced Raman spectroscopy (SERS) substrate showing a strong signal under 638 nm excitation with Raman enhancement factors (EFs) as high as 108. In particular, the capability of detecting Raman analyte down to 10−11 M for RhB and 10−10 M for 4-MBA is demonstrated, simultaneously assessing the enhanced near-field due to the LSPR originating from the processed surface roughness leading to the valuable performances achieved by the n + -n junction diodes. These results offer a new path toward the elaboration of high-efficiency applications of Si structured surfaces in the fields of photoelectric sensing and detection.
Self-starting mode-locking in an all-PM Yb-doped fiber laser oscillator enabled by a 3x3 nonlinear optical lossy loop mirror: erratum
Authors: Pielach Mateusz , Jamrozik Agnieszka , Krupa Katarzyna , Stepanenko Yuriy
Published: September 2024

This erratum corrects an error in Fig. 4 of the original publication [Opt. Express 31, 42136 (2023)10.1364/OE.505449] caused by incorrect values of the vertical axis in logarithmic scale. The correction does not influence the conclusions of the original article, nor does it impact any parameter of the laser oscillator.
Exploration of a vapor cell optical frequency standard scheme implemented using Doppler-free spectroscopy
Authors: Zhang Ang , Zhang Yuechen , Zhao Weihao , Tian Yuan , Zhang Yi , Gu Sihong , Chen Jiehua
Published: September 2024

We implement a compact optical frequency standard scheme with laser frequency locked to the 5S1/2 (F = 2) − 6P3/2 (F′ = 3) transition of the second excited state of 87Rb atoms in a 3 mm cubic glass cell, using a Doppler-free saturated absorption spectroscopy. The experimental results show the frequency stability at the level of 2.2 × 10−12 at 1 s. Furthermore, we conduct an experimental study on the effect of a repump laser on the frequency performance of the saturated absorption spectroscopy optical frequency standard, providing valuable experimental results with reference values for implementing this type of optical atomic clock.
Integrated terahertz topological valley-locked power divider with arbitrary power ratios
Authors: Wang Wen-Ya , Ren Hang , Xu Zhao-Hua , Chen Hong , Li Yuanzhen , Xu Su
Published: September 2024

Integrated power dividers (PDs) are essential in terahertz (THz) communication and radar systems, but miniaturization often leads to performance degradation due to fabrication inaccuracies and sharp bends. Topological photonics offers a solution to these issues, yet creating THz power dividers with arbitrary splitting ratios remains challenging. We present a design methodology for on-chip topological THz power dividers with customizable splitting ratios using valley-locked photonic crystals. These crystals feature a tri-layered structure with two distinct valley Chern number layers and an intermediate semimetal layer. Utilizing the Jackiw–Rebbi model, we show that the characteristic impedance of the valley-locked photonic crystals, and thus the power division ratio, can be tuned by adjusting the semimetal layer width. Our approach is validated through simulations and experiments for both equal (1:1) and unequal (4:9) power ratios. This method enables efficient navigation around sharp bends and robust THz on-chip connectivity.
High-sensitivity miniaturized spectrometers using photonic crystal slab filters
Authors: Wu JingJun , Tang Feng , Wei Cong , Chen Fujia , Chen Peng , Liu Shuangli , Li Ang , Pan Shilong , Ye Xin , Ma Jun , Wang Pan , Chen Hongsheng , Yang Yihao , Zhu Rihong , Zheng Wanguo , Yang Zongyin
Published: September 2024

Miniaturized spectrometers have emerged as pivotal tools in numerous scientific and industrial applications, offering advantages such as portability, cost-effectiveness, and the capability for onsite analysis. Despite these significant benefits, miniaturized spectrometers face critical challenges, particularly in sensitivity. Reduced dimensions often lead to compromises in optical path length and component quality, which can diminish detection limits and limit their applications in areas such as low-light-level measurements. Here we developed a compact spectrometer that integrates an array of photonic crystal slab filters with band-stop spectral transmission characteristics into an image sensor. Compared to traditional gratings or bandpass filter strategies, where each detector can only read light of a single wavelength component, our band-stop strategy allows each detector to read the light of all wavelengths except the band-stop wavelength. This maximizes energy extraction from incident signals, significantly improving the sensitivity of the spectrometer. Spectral reconstruction is achieved mathematically using pre-calibrated band-stop responses combined with a single coded image. Our spectrometer delivers a spectral resolution of 1.9 nm and demonstrates sensitivity more than ten times greater than that of conventional grating spectrometers during fluorescence spectroscopy of Ascaris lumbricoides. The design is fully compatible with complementary metal–oxide–semiconductor (CMOS) technology, allowing for mass production at low costs and thus promising broad deployment in sensitive applications.
Electrically tunable metasurface in TN LC configuration with enhanced quality factor and metaatom-induced alignment
Authors: Chang Xin , Pivnenko Mike , Singh Angadjit , Wu Weijie , Dai Peng , Shrestha Pawan , Chu Daping
Published: September 2024

Dynamic metasurface with subwavelength dimensions has emerged as a key optical technology in recent years. Although various active tuning mechanisms are being proposed, liquid crystal-based dynamic metasurface remains attractive due to its large index variation, electrical tunability, reliability, and mass fabricability. In this work, we report a dynamic metasurface for amplitude modulation in reflection, with twisted nematic liquid crystal configuration to reduce broadband reflection in the off state. The metasurface consists of coupled subwavelength grating fingers, which provide alignment for the liquid crystal without the need for an additional alignment material or process. The alignment of liquid crystal materials was examined between crossed polarizers, and the twist of nematic liquid crystal was confirmed. The coupled grating fingers exhibit a resonance quality factor of 27 at telecommunication wavelength and an amplitude modulation depth of 8 times of the minimum at 1630 nm. This work highlights the potential of liquid crystal-based tunable metasurface, combining polarization control via liquid crystal and spectrum control via metasurface. Furthermore, it also shows a way in which the interaction between liquid crystal and metasurface is used for an alignment layer-free cell assembly process.
Efficient perovskite light-emitting diodes on a flexible substrate
Authors: Zhang Dandan , Liu Leishi , Zhu Teng , Liu Yuan
Published: September 2024

The surface properties of target substrates are crucial for the in situ crystallization and growth of metal halide perovskite films fabricated by the anti-solvent method. In this work, a high-quality quasi-2D perovskite film with various-n phases is fabricated on the commonly used poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) by introducing a branched polyethylenimine (PEI) modifying layer. PEI suppresses the influence of acidic surface of the PEDOT:PSS and regulates the components of the perovskite film, increasing the proportion of large-n phases. Additionally, PEI reduces the formation of defects in perovskite films, leading to higher photoluminescence quantum efficiency and longer photoluminescence lifetime. Based on this high-quality perovskite film, a flexible light-emitting diode with an ultimate current efficiency of 63.2 cd/A is achieved, nearly twofold higher than that of the device (35.1 cd/A) without a PEI modifying layer.
Holographic image denoising for dense droplet field using conditional diffusion model
Authors: Zhang Hang , Wang Yu , Wu Yingchun , Zhang Letian , Wang Boyi , Zhao Yue , Wu Xuecheng
Published: September 2024

The Letter delves into an approach to holographic image denoising, drawing inspiration from the generative paradigm. It introduces a conditional diffusion model framework that effectively suppresses twin-image noises and speckle noises in dense particle fields with a large depth of field (DOF). Specific training and inference configurations are meticulously outlined. For evaluation, the method is tested using calibration dot board data and droplet field data, encompassing gel atomization captured via inline holography and aviation kerosene swirl spray through off-axis holography. The performance is assessed using three distinct metrics. The metric outcomes, along with representative examples, robustly demonstrate its superior noise reduction, detail preservation, and generalization capabilities when compared to two other methods. The proposed method not only pioneers the field of generative holographic image denoising but also highlights its potential for industrial applications, given its reduced dependency on high-quality training labels.
Simulating diffusion and repulsion of charges in single photon semiconductor detectors
Authors: Ballester Manuel , Kaspar Jaromir , Massanés Francesc , Vija Alexander Hans , Katsaggelos Aggelos K.
Published: September 2024

We introduce a novel Monte Carlo approach for simulating charge propagation in semiconductor detectors, accounting for Coulomb repulsion and diffusion over time.
Experimental Evaluation of Photothermal Conversion Magnetite Nanofluids under the Influence of Dynamic Magnetic Field
Authors: Alcalde-Castro Juan Jose , Álvarez-Gil Laura , Restrepo-Martínez Alejandro
Published: September 2024

The study investigates improved energy conversion efficiency in solar thermal systems using an oscillating magnetic field in nanofluid applications. Three concentrations of magnetite/ethylene glycol nanoparticles and ethylene glycol alone are evaluated.
Convective Asymmetries in Thermal Blooming Experiments
Authors: Lane Jeremiah S. , Akers Benjamin F.
Published: September 2024

Simulation and experiment of steady-state thermal blooming of a laser within a confined propagation chamber are compared. The global fluid response to asymmetric laser heating induces local asymmetries in the beam irradiance profile after propagation.
A comparison of EEG encoding models using audiovisual stimuli and their unimodal counterparts
Authors: Desai Maansi , Field Alyssa M. , Hamilton Liberty S.
Published: September 2024

Communication in the real world is inherently multimodal. When having a conversation, typically sighted and hearing people use both auditory and visual cues to understand one another. For example, objects may make sounds as they move in space, or we may use the movement of a person’s mouth to better understand what they are saying in a noisy environment. Still, many neuroscience experiments rely on unimodal stimuli to understand encoding of sensory features in the brain. The extent to which visual information may influence encoding of auditory information and vice versa in natural environments is thus unclear. Here, we addressed this question by recording scalp electroencephalography (EEG) in 11 subjects as they listened to and watched movie trailers in audiovisual (AV), visual (V) only, and audio (A) only conditions. We then fit linear encoding models that described the relationship between the brain responses and the acoustic, phonetic, and visual information in the stimuli. We also compared whether auditory and visual feature tuning was the same when stimuli were presented in the original AV format versus when visual or auditory information was removed. In these stimuli, visual and auditory information was relatively uncorrelated, and included spoken narration over a scene as well as animated or live-action characters talking with and without their face visible. For this stimulus, we found that auditory feature tuning was similar in the AV and A-only conditions, and similarly, tuning for visual information was similar when stimuli were presented with the audio present (AV) and when the audio was removed (V only). In a cross prediction analysis, we investigated whether models trained on AV data predicted responses to A or V only test data similarly to models trained on unimodal data. Overall, prediction performance using AV training and V test sets was similar to using V training and V test sets, suggesting that the auditory information has a relatively smaller effect on EEG. In contrast, prediction performance using AV training and A only test set was slightly worse than using matching A only training and A only test sets. This suggests the visual information has a stronger influence on EEG, though this makes no qualitative difference in the derived feature tuning. In effect, our results show that researchers may benefit from the richness of multimodal datasets, which can then be used to answer more than one research question.
Effects of Schistosoma haematobium infection and treatment on the systemic and mucosal immune phenotype, gene expression and microbiome: A systematic review
Authors: Mertelsmann Anna M. , Bowers Sheridan F. , Wright Drew , Maganga Jane K. , Mazigo Humphrey D. , Ndhlovu Lishomwa C. , Changalucha John M. , Downs Jennifer A.
Published: September 2024

Background

Urogenital schistosomiasis caused by Schistosoma haematobium affects approximately 110 million people globally, with the majority of cases in low- and middle-income countries. Schistosome infections have been shown to impact the host immune system, gene expression, and microbiome composition. Studies have demonstrated variations in pathology between schistosome subspecies. In the case of S. haematobium, infection has been associated with HIV acquisition and bladder cancer. However, the underlying pathophysiology has been understudied compared to other schistosome species. This systematic review comprehensively investigates and assimilates the effects of S. haematobium infection on systemic and local host mucosal immunity, cellular gene expression and microbiome.

Methods

We conducted a systematic review assessing the reported effects of S. haematobium infections and anthelmintic treatment on the immune system, gene expression and microbiome in humans and animal models. This review followed PRISMA guidelines and was registered prospectively in PROSPERO (CRD42022372607). Randomized clinical trials, cohort, cross-sectional, case-control, experimental ex vivo, and animal studies were included. Two reviewers performed screening independently.

Results

We screened 3,177 studies and included 94. S. haematobium was reported to lead to: (i) a mixed immune response with a predominant type 2 immune phenotype, increased T and B regulatory cells, and select pro-inflammatory cytokines; (ii) distinct molecular alterations that would compromise epithelial integrity, such as increased metalloproteinase expression, and promote immunological changes and cellular transformation, specifically upregulation of genes p53 and Bcl-2; and (iii) microbiome dysbiosis in the urinary, intestinal, and genital tracts.

Conclusion

S. haematobium induces distinct alterations in the host’s immune system, molecular profile, and microbiome. This leads to a diverse range of inflammatory and anti-inflammatory responses and impaired integrity of the local mucosal epithelial barrier, elevating the risks of secondary infections. Further, S. haematobium promotes cellular transformation with oncogenic potential and disrupts the microbiome, further influencing the immune system and genetic makeup. Understanding the pathophysiology of these interactions can improve outcomes for the sequelae of this devastating parasitic infection.
Nursing staff’s attitudes towards the prevention of adverse events among hospitalized people with dementia: Protocol of qualitative systematic review and evidence synthesis
Authors: Catalán Lucía , Pot Anne Margriet , Pepper Amy , Harrison Dening Karen , Oliveira Déborah
Published: September 2024

Introduction

People with dementia are more likely than people without dementia to be hospitalized and to experience in-hospital preventable adverse events, such as falls, skin injury, and infection, compared to other hospitalized groups. Negative attitudes towards people with dementia are common among acute healthcare workers and have been linked to a cascade of negative adverse events in this population. However, no qualitative systematic review has ever been conducted to synthesize the existing evidence in this area, which hampers the development of preventative measures.

Aim

This is a protocol for a qualitative systematic review aimed at exploring and synthesizing existing qualitative evidence regarding the attitudes of nursing staff towards the prevention of adverse events among hospitalized people with dementia.

Methods

Literature searches will be performed in PubMed, CINAHL, PsycINFO, Web of Science, Biblioteca Virtual de Salud, Scopus, The Cochrane Library, and Google Scholar. The references of eligible studies will be checked for eligibility. All primary qualitative or mixed-methods studies with a qualitative component published in peer-reviewed academic journals in English, Portuguese, or Spanish will be eligible. There will be no limitations to the date of publication. The selection process will be conducted independently by two researchers using the software Rayyan and then compared and discussed. Any disagreements regarding eligibility will be discussed among the entire research team and resolved via consensus. Methodological quality will be assessed using Cochrane’s guidance. A meta-aggregative approach will be employed to extract and synthesize the evidence using the software package QARI from the JBI. The confidence in the findings will be graded using ConQual.

Implications

This review will help identify and better understand specific attitudinal and psychosocial aspects that influence nursing care delivery for people with dementia in hospital settings. Such data can be used to generate novel explanatory models of nursing behaviors in dementia care, as well as capacity building and training to enhance hospital care for people with dementia globally.
Smartphone region-wise image indoor localization using deep learning for indoor tourist attraction
Authors: Hirokawa Higa Gabriel Toshio , Stuqui Monzani Rodrigo , da Silva Cecatto Jorge Fernando , Balestieri Mariano de Souza Maria Fernanda , de Moraes Weber Vanessa Aparecida , Pistori Hemerson , Matsubara Edson Takashi
Published: September 2024

Smart indoor tourist attractions, such as smart museums and aquariums, require a significant investment in indoor localization devices. The use of Global Positioning Systems on smartphones is unsuitable for scenarios where dense materials such as concrete and metal blocks weaken GPS signals, which is most often the case in indoor tourist attractions. With the help of deep learning, indoor localization can be done region by region using smartphone images. This approach requires no investment in infrastructure and reduces the cost and time needed to turn museums and aquariums into smart museums or smart aquariums. In this paper, we propose using deep learning algorithms to classify locations based on smartphone camera images for indoor tourist attractions. We evaluate our proposal in a real-world scenario in Brazil. We extensively collect images from ten different smartphones to classify biome-themed fish tanks in the Pantanal Biopark, creating a new dataset of 3654 images. We tested seven state-of-the-art neural networks, three of them based on transformers. On average, we achieved a precision of about 90% and a recall and f-score of about 89%. The results show that the proposal is suitable for most indoor tourist attractions.
The impact of liquidity risk and credit risk on bank profitability during COVID-19
Authors: Haris Muhammad , Yao HongXing , Fatima Hijab
Published: September 2024

The COVID-19 outbreak caused a massive setback to the stability of financial system due to emergence of several other risks with COVID, which significantly influenced the continuity of profitable banking operations. Therefore, this study aims to see that how differently the liquidity risk and credit risk influenced the banking profitability during Covid-19 (Q12020 to Q42021) than before COVID (Q12018 to Q42019). The study employs pooled OLS, and OLS fixed & random effects models, to analyze the panel data on a sample of 37 banks currently operating in Pakistan. The results depict that liquidity risk has a positive and significant relationship with return on assets and return on equity, but insignificant relationship with net interest margin. Credit risk has a negative and significant relationship with return on assets, return on equity, and net interest margin. The study also applies quantile regression to address the normality issue in data. The quantile regression results are consistent with pooled OLS, and OLS fixed and random effects results. The study makes valuable suggestions for regulators, policymakers, and others users of financial institutional data. The current study will help to set policies for efficient management of LR and CR.
Stable biomarker discovery in multi-omics data via canonical correlation analysis
Authors: Pusa Taneli , Rousu Juho
Published: September 2024

Multi-omics analysis offers a promising avenue to a better understanding of complex biological phenomena. In particular, untangling the pathophysiology of multifactorial health conditions such as the inflammatory bowel disease (IBD) could benefit from simultaneous consideration of several omics levels. However, taking full advantage of multi-omics data requires the adoption of suitable new tools. Multi-view learning, a machine learning technique that natively joins together heterogeneous data, is a natural source for such methods. Here we present a new approach to variable selection in unsupervised multi-view learning by applying stability selection to canonical correlation analysis (CCA). We apply our method, StabilityCCA, to simulated and real multi-omics data, and demonstrate its ability to find relevant variables and improve the stability of variable selection. In a case study on an IBD microbiome data set, we link together metagenomics and metabolomics, revealing a connection between their joint structure and the disease, and identifying potential biomarkers. Our results showcase the usefulness of multi-view learning in multi-omics analysis and demonstrate StabilityCCA as a powerful tool for biomarker discovery.
Factors related to the intention of choosing shared E-scooters for metro transfer: A survey study integrating weather perception into satisfaction evaluation from Changsha
Authors: Lin Chenyue , Xue Xingjian , Zhu Zhixuan , Luo Yue , Song Rui
Published: September 2024

Shared E-scooter (SE) travel is a low-carbon transportation method that can be further enhanced by integrating with metro systems. This study aims to quantify the impact of the built environment, attitude preferences, weather perception, and other factors on the evaluation and intention to use the "SE-metro transfer" travel mode, as well as how to efficiently and concisely measure and model these effects. Empirical analysis was conducted using questionnaire data from Changsha, China, with 683 participants surveyed. Three satisfaction models were established and compared based on the Technology Acceptance Model (TAM), and an optimal M2 model was expanded to incorporate users’ subjective perceptions of weather, proposing a method to simplify questionnaire length. The study found that well-designed vehicles and infrastructure, along with necessary supporting facilities, play important roles in enhancing SE usage. However, there are still many areas for optimization in Changsha’s SE policies. Despite the advantages of SE in terrain and physical fitness, which have significantly expanded and changed their user base compared to traditional shared bicycles, there is still much potential to adapt to the middle-aged and older user groups. The results of this study can provide valuable insights for professionals and government officials in designing systems, constructing infrastructure, and formulating policies.