bluuebunny/crossref_metadata_2025 huggingface dataset:
Trapping two types of particles using a single optical fiber Bessel beam
Authors: Tang Xiaoyun , Ma Liang , Zhang Yaxun , Zhang Yu , Liu Zhihai
Published: November 2021

We propose and experimentally demonstrate the simultaneous trapping of a high-refractive-index particle and a low-refractive-index particle by using a single fiber optical Bessel beam. The experimental and simulated results verify the stable trapping.
Speech Quality Estimation of an FBG Sensor-based Contact Microphone in Noisy Environment
Authors: Jha Chandan Kumar , Bhattacharjee Sankha Subhra , Chauhan Jainish Nileshkumar , Chakraborty Arup Lal , George Nithin V.
Published: November 2021

We present the design of an FBG sensor-based contact microphone and compare its speech quality to that of a calibrated measurement microphone using perceptual evaluation of speech quality score and spectrogram analysis in noisy environment.
Graphene oxide diaphragm for acoustic fiber sensing
Authors: Monteiro Catarina S. , Silva Susana O. , Santos José Lúıs , Frazão Orlando
Published: November 2021

A fiber sensor composed by a graphene oxide membrane at the tip of a capillary is presented. The graphene oxide membrane acts as a low-reflectivity mirror, distanced from a single mode fiber forming a low finesse Fabry-Perot interferometer. The response of the sensor to acoustic pressure with varying frequency is studied in the range between 5 and 45 kHz, attaining a minimum signal to noise ratio of 14 dB.
10-Million-Cycle Fatigue Test of Fiber Bragg Grating Sensors Packaged into Glass-Fiber Composites
Authors: Huang Mengjiao , Wang Zun , Pan Liu , Wei Rongyao , Liu Zheng , Zhu Pingyu , Soto Marcelo A.
Published: November 2021

The strain response of fiber Bragg grating sensors packaged into glass-fiber composites is investigated in a 10-million-cycle fatigue test. Results demonstrate that after a 27-day test the sensors provide strain measurements showing no accuracy degradation.
Strain Transfer Estimation for Complex Surface-Bonded Optical Fibers in Distributed Sensing Applications
Authors: Bastianini Filippo , Bocheński Paweł , Di Sante Raffaella , Falcetelli Francesco , Marini Diego , Bolognini Gabriele
Published: November 2021

The strain transfer mechanism in surface-bonded optical fibers for distributed sensing is analyzed. A novel and practical methodology to apply conventional analytical models to complex cable geometries is proposed and verified experimentally.
Random Bragg-grating-based tunable random fiber laser with a full-open cavity
Authors: Lv Bing , Zhang Wentao , Miao Shuaijie , Huang Wenzhu , Li Fang
Published: November 2021

A full-open-cavity random fiber laser with compact structure and hundreds of picometers tuning range is proposed. A tunable optical bandpass filter is used in the TRFL for spectral filtering and to choose different laser wavelengths.
Fading-free polarization-sensitive optical fiber sensing
Authors: Wang Xuefeng , Zhao Can , Wu Hao , Tang Ming
Published: November 2021

A novel polarization-based forward transmission system without signal fading is proposed for vibration detection. This system promises potential application in perimeter security and physical parameters measurement.
Resonator with circularly polarization maintaining fiber to suppress polarization fluctuation for resonator fiber optic gyro
Authors: Wang Zhuo , Wang Guochen , Cheng Yu , Gao Wei
Published: November 2021

Resonator with circularly birefringent fiber is designed and applied in resonator fiber optic gyro. The application realizes the suppression of polarization fluctuation between two eigenstate of polarization in resonator, thereby improving long-term stability of gyro.
Enhanced Optical Fiber Lasers and Optical Fiber Sensors Assisted by Micro-drilled Optical Fibers
Authors: Perez-Herrera R. A. , Bravo M. , Roldan-Varona P. , Leandro D. , Cobo L. Rodriguez , Lopez-Higuera J. M. , Lopez-Amo M.
Published: November 2021

Enhanced OFS assisted by micro-drilled optical fibers acting as mirrors are demonstrated. Strain sensitivity improved more than one order of magnitude in comparison with FBG sensors using a 50 μm-waist micro-drilled taper as distributed reflector.
Effect of gamma radiation on the sensing characteristics of FPs and FBGs
Authors: Li Zhuoyue , Xiao Yaqin , Ran Zengling , Yang Tingting , He Xiu , Xiao Yanbo , Shen Feng , Rao Yunjiang , He Zhengxi , Zhu Jialiang , He Peng , Xu Sijie , Chu Wangwei , Zeng Debiao
Published: November 2021

The sensing characteristics of Fabry-Perot interferometers (FPIs) and fiber Bragg gratings (FBGs) after irradiation were studied, in which pressure sensitivity of FPI was stable while temperature sensitivity curves of the irradiated FBG did not coincide.
Demonstration of Strategic-Grade Noise in an Optically Gated Laser-Driven Fiber Optic Gyroscope
Authors: Wheeler Jonathan M. , Digonnet Michel J. F.
Published: November 2021

Dynamic phase biasing in a fiber optic gyroscope (FOG) using square-wave or serrodyne modulation introduces periodic spikes in the optical output that induce noise and drift. We report a laser-driven FOG in which these spikes are removed optically to achieve a record angular random walk of 62 μdeg/√h.
Miniature Fiber-Optic Temperature Sensor with All-Sapphire Structure and Its Field Evaluation
Authors: Yang Shuo , Van Hout Daniel , de Clerck Albrey , Su Xu , Gillespie John , Shi Guannan , Wang Anbo , Ng Wing , Zhu Yizheng
Published: November 2021

This paper presents a miniature all-sapphire-fiber Fabry-Perot temperature sensor and its evaluation in the exhaust flow of a Honeywell turbofan engine. The sensor demonstrates reliable and fast response as compared to a commercial thermocouple.
Challenging the Limits of Interferometric Fiber Sensor Sensitivity with the Optical Harmonic Vernier Effect
Authors: Gomes André D. , Ferreira Marta S. , Bierlich Jörg , Kobelke Jens , Rothhardt Manfred , Bartelt Hartmut , Frazão Orlando
Published: November 2021

We discuss the novel concept of harmonics of the Vernier effect for optical fiber sensors as a tool to break the limits of conventional optical Vernier effect currently used. The new effect provides enhancements scalable with the harmonic order.
Ultrahigh refractive index sensitivity with a reflective fibre optic microcavity in-line interferometer
Authors: Eftimov Tinko , Mikulic Predrag , Arapova Alla , Bock Wojtek J.
Published: November 2021

We report the study of a reflective micro in-line Mach-Zehnder fibre optic interferometer. Sensitivities to surrounding refractive index varying from -12950 to -23000 nm/r.i.u. were obtained for the micro-fibre optic dip SRI sensor.
Temperature gradient sensing using LPGs with non-identic halves
Authors: Eftimov T. , Koffi N’G. , Lesage F.J. , Mikulic P. , Bock W.J. , Akue M.H.
Published: November 2021

In this paper we present theoretical and experimental study of the response to thermal gradients of fiber optic long period gratings (LPG) whose halves have different periods. We have performed theoretical simulations and experimental measurements. LPGs from standard SMF-28 fibers were fabricated by the arc induced method.
Gain-assisted plasmonic/dielectric nanoshells in Optical Tweezers: Non-linear optomechanics and thermal effects
Authors: Polimeno P. , Patti F. , Infusino M. , Sánchez J. , Iatì M. A. , Saija R. , Volpe G. , Maragò O. M. , Veltri A.
Published: November 2021

We study theoretically the optomechanics of a dyed dielectric/metallic nanoshell in Optical Tweezers in a counter-propagating configuration. In addition, we consider the thermophoretic effects due to the interaction between the incident radiation and the nanoparticle metallic component.
Clustering of Janus particles under the effect of optical forces driven by hydrodynamic fluxes
Authors: Callegari Agnese , Mousavi S. Masoumeh , Kasianiuk Iryna , Kasyanyuk Denis , Velu Sabareesh K. P. , Biancofiore Luca , Volpe Giovanni
Published: November 2021

Hydrodynamic fluxes generated by Janus particles in an optical potential drive reversible clustering of colloids.
Cross-Seeding of Amyloid-β in an Optically Controlled Thermophoretic Trap
Authors: Fanselow B. , Hartmann F. , Zschocke M. , Thalheim T. , Adler J. , Huster D. , Cichos F.
Published: November 2021

Processes such as secondary nucleation or fragmentation play a fundamental role in the formation and growth of amyloid fibrils. Here, we show that under physiological conditions those usually rare events occur nearly certain.
Optical trapping dynamics under femtosecond pulsed excitation: A comparative study with particles of different sizes
Authors: Devi Anita , Yadav Sumit , De Arijit Kumar
Published: November 2021

We present a comparative study on optical trapping dynamics for particles of different sizes. . The trapped particles’ confinement time is found to be nicely correlated with the axial trap stiffness.
Non-invasive optoacoustic imaging of tau in P301L mice
Authors: Vagenknecht Patrick , Dean-Ben Xose Luis , Gerez Juan Atilio , Chen Zhenyue , Nitsch Roger M , Klohs Jan , Razansky Daniel , Ni Ruiqing
Published: November 2021

Abnormal tau accumulation plays an important role in Alzheimer’s disease and frontotemporal dementia. There is a gap in preclinical high-resolution imaging of tau. Here we showed non-invasive whole-brain optoacoustic tau imaging in P301L tau mice.
3D OCT characterization and quantification of refractive indices of bacteria and biofilms with antibiotic interventions
Authors: Zaki Farzana R. , Sudhir Kavya , Won Jungeun , Monroy Guillermo L. , Choi Honggu , Chaney Eric J. , Spillman Darold R. , Boppart Stephen A.
Published: November 2021

Using 3D OCT, we have quantified the refractive indices of ear-infection causing bacteria and biofilms with antibiotics interventions. This approach reveals changing optical properties of bacteria in biofilms following the delivery of antibiotics.
Multispectral in ovo imaging of intracellular and extracellular EGFR using paired-agent principles
Authors: Torres Veronica C. , Wang Lei , Hodge Sassan , Solanki Allison , McMahon Nathan , Tichauer Kenneth M. , Gibbs Summer L. , Samkoe Kimberley S.
Published: November 2021

The chicken chorioallantoic membrane is a promising xenograft tumor model to quantify intracellular and extracellular EGFR concentration as demonstrated through multispectral and paired-agent imaging approaches.
Continuously streaming compressed high-speed photography using time delay integration
Authors: Park Jongchan , Gao Liang
Published: November 2021

An imaging system capable of acquiring high-resolution data at a high speed is in demand. However, the amount of optical information captured by a modern camera is limited by the data transfer bandwidth of electronics, resulting in a reduced spatial and temporal resolution. To overcome this problem, we developed continuously streaming compressed high-speed photography, which can record a dynamic scene with an unprecedented space-bandwidth-time product. By performing compressed imaging in a time-delay-integration manner, we continuously recorded a 0.85 megapixel video at 200 kHz, corresponding to an information flux of 170 gigapixels per second.
Simulations of Compensated-Beacon Adaptive Optics using a Fresnel Wavefront Sensor
Authors: Follansbee Joshua H. , Crepp Justin R. , Banet Matthias T. , Radosevich Cameron J. , Spencer Mark F.
Published: November 2021

This paper uses wave-optics simulations to perform compensated-beacon adaptive optics using least-squares phase reconstruction with Fresnel and Shack-Hartmann wavefront sensors. Overall, the two noiseless sensors perform comparably for weak to mod- erately strong scintillation conditions.
Improving Tolerance to Atmospheric Turbulence Effects in FSO Quantum Communications by Adaptive Optics
Authors: Nafria Vijay , Djordjevic Ivan B.
Published: November 2021

We demonstrate that adaptive optics (AO) can be used to improve tolerance to atmospheric turbulence in free-space optical (FSO) quantum communications. Both the overall secret-key rate and quantum bit-error rate for BB84 protocol have been significantly improved by the AO.
Assessment of Visibility from Aerosol Number Concentration
Authors: Fiorino Steven , Keefer Kevin , Jagoda Daniel
Published: November 2021

In this paper we describe a method to quantify visibility distance based on aerosol number concentration in the size spectrum 5nm to 2.5μm (PM2.5). This method allows complete automation of visibility assessments in weather observations.
Classification of Turbulence-Degraded Imagery Using Neural Networks
Authors: LeMaster Daniel A. , Leung Steven , Mendoza-Schrock Olga L.
Published: November 2021

A more realistic simulation is used to evaluate claims made in a recently published work on object classification for turbulence degraded imagery.
Fast Statistical Testing of Scintillated, Speckled Irradiance
Authors: Burrell Derek , Beason Melissa
Published: November 2021

We propose statistical metrics to quickly evaluate speckle’s influence on atmospheric wavefront sensing. Integrating over multiple pupil-plane speckle re- alizations, we find that the skewness in irradiance is ideally 1.
Silicon Interference Solar Cells: Targeted and Broadband Wavelength Absorption Enhancement in Ultrathin Absorbers
Authors: Durmaz Zeynep , Husein Sebastian , Saive Rebecca
Published: November 2021

Computational demonstration of an interference solar cell design which enhances absorption in <13 μm silicon absorbers for 300-1100 nm wavelengths, yielding a 19% current density increase compared to silicon heterojunction solar cells of similar thickness.
Fabrication and characterization of intermediate band CdTe quantum dot solar cells
Authors: Deligiannakis Vasilios , Begliarbekov Milan , Cheng Piphat , Kuskovsky Igor , Tamargo Maria C
Published: November 2021

An intermediate band solar cell (IBSC) device based on type-II CdTe/ZnCdSe sub-monolayer quantum dots is presented. I-V and two step photon measurements are compared to a reference solar cell and show improved properties for the IBSCs.
Alkyl Substituent Engineering for Efficient Photoconversion Efficiency in Small Molecular Organic Photovoltaics
Authors: Suzuki Mitsuharu , Yamada Hiroko
Published: November 2021

The recent surge in the efficiency of organic photovoltaic devices (OPVs) largely hinges on the reduction of energy loss (Eloss) that leads to improvements in open-circuit voltage (VOC). However, there are still many unclarified factors regarding the relationship between the molecular structure and VOC, hampering the establishment of widely applicable, effective principles for the design of active-layer materials. In this contribution, we examined the origin of the large VOC shifts induced by minor structural differences in end-alkyl substituents on a series of anthracene-based p-type compounds.
New Architecture and Bonding Process for III-V//Si Tandem Solar Cells
Authors: Nguyen Phuong-Linh , Chancerel François , Baranek Philippe , Höhn Oliver , Lackner David , Dimroth Frank , Faustini Marco , Collin Stéphane , Cattoni Andrea
Published: November 2021

We propose an easy and low-cost bonding method for III-V//Si tandem solar cells, based on conductive sol-gel-derived and hybrid materials. The design enables current matching and photon recycling. First prototypes have been demonstrated successfully.
Bend sensing with flexible, wavelength-tunable random laser
Authors: Lee Seungsu , Kim Hansol , Jeong Yoonchan
Published: November 2021

We present a flexible random laser with unique properties, such as curvature-dependent wavelength tunability, easy and low-cost fabrication, and flexibility with the application in an optical bend sensor.
Design Considerations for Fit-for-Purpose SERS Sensors
Authors: Tay Li-Lin , Hulse John
Published: November 2021

Surface enhanced Raman scattering (SERS) sensors provide tremendous sensitivity and specificity enabling a large number of analytical applications. They work well with analytes that have good affinity towards the plasmonic nanostructures that support SERS. For molecules that have little or no affinity to the nanostructures, additional surface functionalization is necessary. Carrying out surface functionalization within a highly confined plasmonic nanocavity is challenging and a number of factors must be taken into account in the design of SERS devices. Here, we highlight the general design considerations for fit-for-purpose SERS devices in order to meet the operational requirement of a user.
Improved Gas-Phase Infrared Analysis of Nitrobenzene using Nanoporous Silica Preconcentrator
Authors: Day Coco , Hutter Tanya
Published: November 2021

Gas-phase infrared (IR) is often insufficiently sensitive to detect low-vapor-pressure explosives. A nanoporous silica preconcentrator was used to achieve a three-fold sensitivity enhancement of gas-phase IR for nitrobenzene.
Compressed-sensing white light interferometry
Authors: Liu Qiang , Li Shimin , Zhou Da-Peng , Jing Zhenguo , Peng Wei
Published: November 2021

We propose a compressed sensing based white light interferometry. Utilizing a programmable semiconductor laser source, the time-varying interferometric spectra of an Fabry-Pérot sensing head can be compressively sampled and effectively reconstructed, realizing high- speed absolute vibration measurement.
Mid-infrared biosensors with grating coupled graphene based hyperbolic metamaterial
Authors: Cynthia Sarah , Ahmed Rajib , Islam Sharnali , Ali Khaleda , Hossain Mainul
Published: November 2021

Metal based plasmonic biosensors suffer from high losses in the mid-IR wavelengths, limiting detection sensitivity. Graphene based hyperbolic metamaterials offer strong, tunable, mid-IR localized plasmons, suitable for detecting nanometric biomolecules with high sensitivity.
Luminol chemiluminescence enhancement via the localized surface plasmon resonance in metal nanoparticles
Authors: Dadadzhanov D.R. , Kirichek K. , Kurshanov D.A. , Gladskikh I.A. , Sapunova A.A. , Bukatin A. , Toropov N.A. , Vartanyan T.A.
Published: November 2021

Plasmon-enhanced chemiluminescence of luminol spread over an array of supported silver nanoparticles was investigated. The maximum enhancement factor was obtained when the plasmon absorption band of silver nanoparticles was overlapped with the luminol chemiluminescence band.
Fluid flow measurement using LPG fiber optic sensor
Authors: Yana L , Mosquera L , Loayza F
Published: November 2021

An LPG sensor attached to a bar in a cantilever configuration is used to measure the speed of the water that flows in a pipe, when a 600-liter tank is emptied.
Fast Magnetic Field Sensing Utilizing Magnetic Fluid as the Cladding of Infiltrated Photonic Crystal Fiber
Authors: Azad Saeed , Izquierdo Ricardo , Ung Bora
Published: November 2021

A photonic crystal fiber infiltrated with magnetic fluid is proposed for measuring magnetic field in harsh and hard to reach places. Experimental results indicated a fast response and showed a good fit with simulations.
Dynamic Tunability of Sensitivity of Graphene based Surface Plasmon Resonance Sensor
Authors: Wei Tingyi , Reid Jeremy L. , Gollapalli Ravi P. , Vickery Derrick , Thompson D. Brian , Gren Cameron K.
Published: November 2021

The effect of electrical bias across the SPR sensor surface to dynamically tune its refractive index is investigated. This technique provides a dynamic sensor surface and a handle to enhance and tune the sensor sensitivity.
Electro-Plasmonic Biosensors for Ultrasensitive Imaging of Electric Field Dynamics and Bioelectric Cell Signaling
Authors: Habib Ahsan , Zhu Xiangchao , Can Uryan I. , McLanahan Maverick L. , Zorlutuna Pinar , Yanik Ahmet A.
Published: November 2021

Plasmonic biosensing is the gold standard technique for label-free detection of molecular accumulation. Here, we introduce a unique electro-plasmonic biosensing technique enabling contactless measurement of electric field dynamics and bioelectric signals with unprecedented spatiotemporal resolution.
The Pulse Shape Effect on Signal-to-Noise Ratio for φ-OTDR Systems
Authors: Uyar Faruk , Nehir Anıl , Kartaloglu Tolga , Özbay Ekmel , Ozdur Ibrahim
Published: November 2021

We experimentally investigate the effect of the probe pulse shape on the performance of φ-OTDR based distributed vibration sensors by comparing the SNR values for rectangular, Gaussian and triangular pulses.
Proton Bragg Peak Detection with Perfluorinated Polymer Fibre
Authors: Olusoji Olugbenga J. , Penner Crystal , Bélanger-Champagne Camille , Kam Wern , Hoehr Cornelia , O’Keeffe Sinead
Published: November 2021

Perfluorinated polymer fibre are tested to characterise the Bragg Peak of a 69 MeV proton beam for comparison to Marcus chamber results. This paper presents the potential of perfluorinated polymer fibre in relative proton dosimetry applications.
Filter-coated Raman fiber bundle probe and deep neural networks for oral cancer diagnostics
Authors: Gebrekidan Medhanie Tesfay , Braeuer Andreas Siegfried
Published: November 2021

Fibers can be coated individually with optical filters and bundled to detect Raman spectrum with two excitation and detection channels. Deep neural networks purify Raman spectra and identify oral squamous cell carcinoma (OSCC) with an accuracy of 95%.
Towards low timing jitter photon number-resolved Digital Silicon Photomultiplier
Authors: Berretta Davide , Incoronato Alfonso , Sesta Vincenzo , Villa Federica
Published: November 2021

We discuss the design of an innovative general-purpose Digital Silicon Photomultiplier (d-SiPM) with 32 × 32 SPADs, aiming at improving dynamic range and readout timing jitter, by means of a mixed-signal architecture.
Wearable devices for remote monitoring of transcutaneous tissue oxygenation
Authors: Cascales Juan Pedro , Roussakis Emmanuel , Greenfield Daniel , Witthauer Lilian , Goss Avery , Li Xiaolei , Marks Haley L , Chen Yenyu , Evans Conor L
Published: November 2021

We have developed wireless wearable devices to monitor tissue oxygenation transcutaneously by detecting the phosphorescence lifetime and intensity of an oxygen sensing film, paired with machine learning. The devices have been tested in vivo.
Direct Single-Particle Detection and Sizes Recognition of Adenovirus with Whispering-Gallery Mode Resonances
Authors: Toropov Nikita , Osborne Eleanor , Joshi Lovleen Tina , Vollmer Frank
Published: November 2021

We demonstrate detection of single particles of adenovirus attaching to a whispering gallery mode resonator without linkers and antibodies. Instead of conventional methods of achieving selectivity via antibodies, we propose to distinguish viral particles through correlation of resonance line changes with virus size.
Phase preserving passive spectral enhancement of short optical pulses
Authors: Crockett Benjamin , Cortés Luis Romero , Konatham Saikrishna Reddy , Azaña José
Published: November 2021

We demonstrate that frequency-domain passive amplification of optical pulses through the Talbot effect preserves the phase information, enabling an enhanced reconstruction of the complex-field temporal waveform, with resolutions down to ~2ps.
Memory assessment of nonlinear optical waveguides using standard DSP
Authors: Hansen Henrik Enggaard , Girouard Peter David , Frandsen Lars H. , Oxenløwe Leif K. , Forchhammer Søren , Yankov Metodi P.
Published: November 2021

Linear equalization is used to assess the impact of memory effects on 10 Gb/s OOK signals induced by wavelength conversion in a deuterated amorphous silicon wave-guide. A longer equalizer is required for higher pump powers.
Low Bandwidth Detection of High Data Rate Nyquist Signals
Authors: Meier Janosch , Misra Arijit , Preußler Stefan , Schneider Thomas
Published: November 2021

We propose a new signal demultiplexing technique for rectangular, high-bandwidth Nyquist data, that neither for the sampling, nor the electrical signal processing needs any high- bandwidth devices. The method is suitable for integration on any platform.
Photonic convolutional accelerator and neural network in the Tera-OPs regime based on soliton crystal Kerr microcombs
Authors: Tan M. , Xu X. , Wu J. , Boes A. , Corcoran B. , Nguyen T. , Chu S. T. , Little B. E. , Morandotti R. , Lowery A.J. , Mitchell A. , Hicks D. , Moss D. J.
Published: November 2021

We report a new approach to ONNs based on integrated Kerr micro-combs that is programmable, highly scalable and capable of reaching ultra-high speeds. We demonstrate a single neuron perceptron at 11.9 Giga-OPS at 8 bits per OP, or 95.2 Gbps. We then demonstrate a convolutional accelerator operating beyond 11 TeraOPs/s. We test the perceptron on handwritten-digit recognition and cancer-cell detection — achieving over 90% and 85% accuracy, respectively.
Tilted-Beam-Enabled Optical Equalization for PAM-4 Transmission in VCSEL-MMF Links
Authors: Li Shanglin , Mojaver Hassan Rahbardar , Liboiron-Ladouceur Odile
Published: November 2021

A tilted-beam-enabled optical equalization scheme efficiently extends the VCSEL-MMF channel bandwidth. A proof-of-principle PAM-4 transmission over MMF shows a 60% power penalty improvement over a conventional central launch.
Blind Equalization for Coherent Optical Communications Based on Variational Inference
Authors: Lauinger Vincent , Buchali Fred , Schmalen Laurent
Published: November 2021

We propose a novel equalization technique for coherent optical communications, which can improve the performance of existing linear equalizers, in particular for probabilistic shaping, and enables powerful neural-network-based equalizers.
Impact of Laser Phase Noise on Optimizing the Constellation Size for Probabilistically Shaped Signals
Authors: Zhang Qiulin , Shu Chester
Published: November 2021

Probabilistically shaped signals with intermediate constellation sizes are found to be relatively tolerant to laser phase noise. We demonstrate experimentally that PS-100 QAM is superior to PS-256 QAM for 200-kHz sum linewidth heterodyne detection.
PIC-based Binary-Weighting Parallel Digital-to-Analog Converter
Authors: Meng Jiawei , Miscuglio Mario , George Jonathan , Babakhani Aydin , Sorger Volker J.
Published: November 2021

Here, we introduce a novel parallel binary-weighed digital-to-analog converter on a silicon photonic integrated platform with a sample efficiency exceeding 120 G-samples per second. And an about 1 square millimeter footprint.
Optical PRBS Generation with Threefold Bandwidth of the Employed Electronics and Photonics
Authors: Singh Karanveer , Meier Janosch , Preußler Stefan , Kress Christian , Scheytt J. Christoph , Schneider Thomas
Published: November 2021

We present the optical generation of a 300 Gbaud PRBS-7 data signal based on time-division multiplexing of Nyquist sinc-pulse sequences. The employed electronic and photonic components need only one-third of the final bandwidth.
Dual-frequency Optoelectronic Oscillator Incorporating Multiband Microwave Photonic Filter in a Single Cavity
Authors: Liu Ling , Jin Xian , Ning Tigang , Chen Lawrence R. , Capmany José
Published: November 2021

We propose a dual-frequency optoelectronic oscillator based on a single cavity. Using optical spectral slicing, we can obtain tunable dual-frequency outputs simultaneously and alternate switching between single-frequency and dual-frequency outputs.
A Simple Parity-Time-Symmetric Optoelectronic Oscillator Based on All-Fiber Coupling
Authors: Özgün Ege , Uyar Faruk , Kartaloglu Tolga , Ozbay Ekmel , Ozdur Ibrahim
Published: November 2021

We experimentally demonstrate a simple parity-time-symmetric optoelectronic oscillator based on all-fiber coupling with single-mode microwave oscillation at 9.5 GHz possessing a phase noise value of –116.2 dBc/Hz at 10 kHz offset.
Assembly of infectious Kaposi’s sarcoma-associated herpesvirus progeny requires formation of a pORF19 pentamer
Authors: Naniima Peter , Naimo Eleonora , Koch Sandra , Curth Ute , Alkharsah Khaled R. , Ströh Luisa J. , Binz Anne , Beneke Jan-Marc , Vollmer Benjamin , Böning Heike , Borst Eva Maria , Desai Prashant , Bohne Jens , Messerle Martin , Bauerfeind Rudolf , Legrand Pierre , Sodeik Beate , Schulz Thomas F. , Krey Thomas
Published: November 2021

Herpesviruses cause severe diseases particularly in immunocompromised patients. Both genome packaging and release from the capsid require a unique portal channel occupying one of the 12 capsid vertices. Here, we report the 2.6 Å crystal structure of the pentameric pORF19 of the γ-herpesvirus Kaposi’s sarcoma-associated herpesvirus (KSHV) resembling the portal cap that seals this portal channel. We also present the structure of its β-herpesviral ortholog, revealing a striking structural similarity to its α- and γ-herpesviral counterparts despite apparent differences in capsid association. We demonstrate pORF19 pentamer formation in solution and provide insights into how pentamerization is triggered in infected cells. Mutagenesis in its lateral interfaces blocked pORF19 pentamerization and severely affected KSHV capsid assembly and production of infectious progeny. Our results pave the way to better understand the role of pORF19 in capsid assembly and identify a potential novel drug target for the treatment of herpesvirus-induced diseases.
SARS-CoV-2 vaccine uptake in a multi-ethnic UK healthcare workforce: A cross-sectional study
Authors: Martin Christopher A. , Marshall Colette , Patel Prashanth , Goss Charles , Jenkins David R. , Ellwood Claire , Barton Linda , Price Arthur , Brunskill Nigel J. , Khunti Kamlesh , Pareek Manish
Published: November 2021

Background

Healthcare workers (HCWs) and ethnic minority groups are at increased risk of COVID-19 infection and adverse outcomes. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is now available for frontline UK HCWs; however, demographic/occupational associations with vaccine uptake in this cohort are unknown. We sought to establish these associations in a large UK hospital workforce.

Methods and findings

We conducted cross-sectional surveillance examining vaccine uptake amongst all staff at University Hospitals of Leicester NHS Trust. We examined proportions of vaccinated staff stratified by demographic factors, occupation, and previous COVID-19 test results (serology/PCR) and used logistic regression to identify predictors of vaccination status after adjustment for confounders. We included 19,044 HCWs; 12,278 (64.5%) had received SARS-CoV-2 vaccination. Compared to White HCWs (70.9% vaccinated), a significantly smaller proportion of ethnic minority HCWs were vaccinated (South Asian, 58.5%; Black, 36.8%; p < 0.001 for both). After adjustment for age, sex, ethnicity, deprivation, occupation, SARS-CoV-2 serology/PCR results, and COVID-19-related work absences, factors found to be negatively associated with vaccine uptake were younger age, female sex, increased deprivation, pregnancy, and belonging to any non-White ethnic group (Black: adjusted odds ratio [aOR] 0.30, 95% CI 0.26–0.34, p < 0.001; South Asian: aOR 0.67, 95% CI 0.62–0.72, p < 0.001). Those who had previously had confirmed COVID-19 (by PCR) were less likely to be vaccinated than those who had tested negative. Limitations include data being from a single centre, lack of data on staff vaccinated outside the hospital system, and that staff may have taken up vaccination following data extraction.

Conclusions

Ethnic minority HCWs and those from more deprived areas as well as younger staff and female staff are less likely to take up SARS-CoV-2 vaccination. These findings have major implications for the delivery of SARS-CoV-2 vaccination programmes, in HCWs and the wider population, and should inform the national vaccination programme to prevent the disparities of the pandemic from widening.
Retinoic acid treatment recruits macrophages and increases axonal regeneration after optic nerve injury in the frog Rana pipiens
Authors: De La Rosa-Reyes Valeria , Duprey-Díaz Mildred V. , Blagburn Jonathan M. , Blanco Rosa E.
Published: November 2021

Retinoic acid (RA) plays major roles during nervous system development, and during regeneration of the adult nervous system. We have previously shown that components of the RA signaling pathway are upregulated after optic nerve injury, and that exogenous application of all-trans retinoic acid (ATRA) greatly increases the survival of axotomized retinal ganglion cells (RGCs). The objective of the present study is to investigate the effects of ATRA application on the macrophages in the optic nerve after injury, and to determine whether this affects axonal regeneration. The optic nerve was crushed and treated with PBS, ATRA and/or clodronate-loaded liposomes. Nerves were examined at one and two weeks after axotomy with light microscopy, immunocytochemistry and electron microscopy. ATRA application to the optic nerve caused transient increases in the number of macrophages and microglia one week after injury. The macrophages are consistently labeled with M2-type markers, and have considerable phagocytic activity. ATRA increased ultrastructural features of ongoing phagocytic activity in macrophages at one and two weeks. ATRA treatment also significantly increased the numbers of regenerating GAP-43-labeled axons. Clodronate liposome treatment depleted macrophage numbers by 80%, completely eliminated the ATRA-mediated increase in axonal regeneration, and clodronate treatment alone decreased axonal numbers by 30%. These results suggest that the success of axon regeneration is partially dependent on the presence of debris-phagocytosing macrophages, and that the increases in regeneration caused by ATRA are in part due to their increased numbers. Further studies will examine whether macrophage depletion affects RGC survival.
Regular testing of asymptomatic healthcare workers identifies cost-efficient SARS-CoV-2 preventive measures
Authors: Sanchez-Taltavull Daniel , Castelo-Szekely Violeta , Murugan Shaira , Hamley Jonathan I. D. , Rollenske Tim , Ganal-Vonarburg Stephanie C. , Büchi Isabel , Keogh Adrian , Li Hai , Salm Lilian , Spari Daniel , Yilmaz Bahtiyar , Zimmermann Jakob , Gerfin Michael , Roldan Edgar , Beldi Guido ,   UVCM-COVID researchers
Published: November 2021

Protecting healthcare professionals is crucial in maintaining a functioning healthcare system. The risk of infection and optimal preventive strategies for healthcare workers during the COVID-19 pandemic remain poorly understood. Here we report the results of a cohort study that included pre- and asymptomatic healthcare workers. A weekly testing regime has been performed in this cohort since the beginning of the COVID-19 pandemic to identify infected healthcare workers. Based on these observations we have developed a mathematical model of SARS-CoV-2 transmission that integrates the sources of infection from inside and outside the hospital. The data were used to study how regular testing and a desynchronisation protocol are effective in preventing transmission of COVID-19 infection at work, and compared both strategies in terms of workforce availability and cost-effectiveness. We showed that case incidence among healthcare workers is higher than would be explained solely by community infection. Furthermore, while testing and desynchronisation protocols are both effective in preventing nosocomial transmission, regular testing maintains work productivity with implementation costs.
In-silico study of accuracy and precision of left-ventricular strain quantification from 3D tagged MRI
Authors: Berberoğlu Ezgi , Stoeck Christian T. , Moireau Philippe , Kozerke Sebastian , Genet Martin
Published: November 2021

Cardiac Magnetic Resonance Imaging (MRI) allows quantifying myocardial tissue deformation and strain based on the tagging principle. In this work, we investigate accuracy and precision of strain quantification from synthetic 3D tagged MRI using equilibrated warping. To this end, synthetic biomechanical left-ventricular tagged MRI data with varying tag distance, spatial resolution and signal-to-noise ratio (SNR) were generated and processed to quantify errors in radial, circumferential and longitudinal strains relative to ground truth. Results reveal that radial strain is more sensitive to image resolution and noise than the other strain components. The study also shows robustness of quantifying circumferential and longitudinal strain in the presence of geometrical inconsistencies of 3D tagged data. In conclusion, our study points to the need for higher-resolution 3D tagged MRI than currently available in practice in order to achieve sufficient accuracy of radial strain quantification.
Longitudinal analysis of sociodemographic, clinical and therapeutic factors of HIV-infected individuals in Kinshasa at antiretroviral therapy initiation during 2006-2017
Authors: Ngongo Nadine Mayasi , Darcis Gilles , Nanituna Hippolyte Situakibanza , Mambimbi Marcel Mbula , Maes Nathalie , Mashi Murielle Longokolo , Bepouka Izizag Ben , Moutschen Michel , Lepira Bompeka François
Published: November 2021

Background

The benefits of antiretroviral therapy (ART) underpin the recommendations for the early detection of HIV infection and ART initiation. Late initiation (LI) of antiretroviral therapy compromises the benefits of ART both individually and in the community. Indeed, it promotes the transmission of infection and higher HIV-related morbidity and mortality with complicated and costly clinical management.

This study aims to analyze the evolutionary trends in the median CD4 count, the median time to initiation of ART, the proportion of patients with advanced HIV disease at the initiation of ART between 2006 and 2017 and their factors.

Methods and findings

HIV-positive adults (≥ 16 years old) who initiated ART between January 1, 2006 and December 31, 2017 in 25 HIV care facilities in Kinshasa, the capital of DRC, were eligible. The data were processed anonymously. LI is defined as CD4≤350 cells/μl and/or WHO clinical stage III or IV and advanced HIV disease (AHD), as CD4≤200 cells/μl and/or stage WHO clinic IV. Factors associated with advanced HIV disease at ART initiation were analyzed, irrespective of year of enrollment in HIV care, using logistic regression models.

A total of 7278 patients (55% admitted after 2013) with an average age of 40.9 years were included. The majority were composed of women (71%), highly educated women (68%) and married or widowed women (61%). The median CD4 was 213 cells/μl, 76.7% of patients had CD4≤350 cells/μl, 46.1% had CD4≤200 cells/μl, and 59% of patients were at WHO clinical stages 3 or 4. Men had a more advanced clinical stage (p <0.046) and immunosuppression (p<0.0007) than women.

Overall, 70% of patients started ART late, and 25% had AHD. Between 2006 and 2017, the median CD4 count increased from 190 cells/μl to 331 cells/μl (p<0.0001), and the proportions of patients with LI and AHD decreased from 76% to 47% (p< 0.0001) and from 18.7% to 8.9% (p<0.0001), respectively.

The median time to initiation of ART after screening for HIV infection decreased from 40 to zero months (p<0.0001), and the proportion of time to initiation of ART in the month increased from 39 to 93.3% (p<0.0001) in the same period.

The probability of LI of ART was higher in married couples (OR: 1.7; 95% CI: 1.3–2.3) (p<0.0007) and lower in patients with higher education (OR: 0.74; 95% CI: 0.64–0.86) (p<0.0001).

Conclusion

Despite increasingly rapid treatment, the proportions of LI and AHD remain high. New approaches to early detection, the first condition for early ART and a key to ending the HIV epidemic, such as home and work HIV testing, HIV self-testing and screening at the point of service, must be implemented.
Genetic predispositions moderate the effectiveness of tobacco excise taxes
Authors: Slob Eric A. W. , Rietveld Cornelius A.
Published: November 2021

Background

Tobacco consumption is one of the leading causes of preventable death. In this study, we analyze whether someone’s genetic predisposition to smoking moderates the response to tobacco excise taxes.

Methods

We interact polygenic scores for smoking behavior with state-level tobacco excise taxes in longitudinal data (1992-2016) from the US Health and Retirement Study (N = 12,058).

Results

Someone’s genetic propensity to smoking moderates the effect of tobacco excise taxes on smoking behavior along the extensive margin (smoking vs. not smoking) and the intensive margin (the amount of tobacco consumed). In our analysis sample, we do not find a significant gene-environment interaction effect on smoking cessation.

Conclusions

When tobacco excise taxes are relatively high, those with a high genetic predisposition to smoking are less likely (i) to smoke, and (ii) to smoke heavily. While tobacco excise taxes have been effective in reducing smoking, the gene-environment interaction effects we observe in our sample suggest that policy makers could benefit from taking into account the moderating role of genes in the design of future tobacco control policies.
Incidence of fraud and adulterations in ASEAN food/feed exports: A 20-year analysis of RASFF’s notifications
Authors: Owolabi Iyiola Oluwakemi , Olayinka Joshua Akinlolu
Published: November 2021

This paper explored the occurrence of food fraud and adulterations (FFA) in exports from the Association of South- East Asia Nations (ASEAN), with implications on food chain and international trade. Data from European Union Rapid Alert System for Food and Feed (EU RASFF) about FFA notifications on ASEAN exports for a period of 20 years (2000–2020) were extracted and analyzed. Results from this study revealed that of all ten ASEAN member countries, seven had cases of FFA notified in the database with Thailand (n = 47, 32%) and the Philippines (n = 37, 26%) receiving the highest frequency of notifications in the region. There was a statistical significance difference in frequency of notifications received on products from these seven countries with herbs and spices ranking highest (n = 22, 15%). Highest notifications of FFA on ASEAN exports came from the United Kingdom (n = 31, 21%). All the seven countries experienced border rejections and consequent destruction of food products especially on exports from Indonesia where 95% of product with FFA were border rejected. Border rejections on products from these countries were significantly different. Therefore, a thorough implementation system, appropriate testing and constantly updating each country’s FFA database could aid actions in curtailing future events.
Factors affecting brain structure in smoking-related diseases: Chronic Obstructive Pulmonary Disease (COPD) and coronary artery disease
Authors: Spilling Catherine A. , Dhillon Mohani-Preet K. , Burrage Daniel R. , Ruickbie Sachelle , Baker Emma H. , Barrick Thomas R. , Jones Paul W.
Published: November 2021

Background

Changes in brain structure and cognitive decline occur in Chronic Obstructive Pulmonary Disease (COPD). They also occur with smoking and coronary artery disease (CAD), but it is unclear whether a common mechanism is responsible.

Methods

Brain MRI markers of brain structure were tested for association with disease markers in other organs. Where possible, principal component analysis (PCA) was used to group markers within organ systems into composite markers. Univariate relationships between brain structure and the disease markers were explored using hierarchical regression and then entered into multivariable regression models.

Results

100 participants were studied (53 COPD, 47 CAD). PCA identified two brain components: brain tissue volumes and white matter microstructure, and six components from other organ systems: respiratory function, plasma lipids, blood pressure, glucose dysregulation, retinal vessel calibre and retinal vessel tortuosity. Several markers could not be grouped into components and were analysed as single variables, these included brain white matter hyperintense lesion (WMH) volume. Multivariable regression models showed that less well organised white matter microstructure was associated with lower respiratory function (p = 0.028); WMH volume was associated with higher blood pressure (p = 0.036) and higher C-Reactive Protein (p = 0.011) and lower brain tissue volume was associated with lower cerebral blood flow (p<0.001) and higher blood pressure (p = 0.001). Smoking history was not an independent correlate of any brain marker.

Conclusions

Measures of brain structure were associated with a range of markers of disease, some of which appeared to be common to both COPD and CAD. No single common pathway was identified, but the findings suggest that brain changes associated with smoking-related diseases may be due to vascular, respiratory, and inflammatory changes.
An assessment of a conservation strategy to increase garden connectivity for hedgehogs that requires cooperation between immediate neighbours: A barrier too far?
Authors: Gazzard Abigail , Boushall Anne , Brand Emma , Baker Philip J.
Published: November 2021

Urban areas are associated with high levels of habitat fragmentation. For some terrestrial species with limited climbing abilities, property boundaries can pose a significant problem by limiting access to residential gardens. The West European hedgehog (Erinaceus europaeus) has declined markedly in the UK but is commonly found in areas of human habitation, including residential gardens. ‘Hedgehog Street’ is a public engagement campaign aimed at recruiting volunteers (‘Hedgehog Champions’) to create access points (‘hedgehog highways’) across garden boundaries to improve habitat connectivity. In this study, we used a series of questionnaire surveys to explore motivations for and obstacles to the creation of highways. Householders were more likely to have created a highway if they were already aware of the Hedgehog Street campaign, if their garden contained a high number of wildlife-friendly features and if they considered watching wildlife to be important. Hedgehog Champions created, on average, 1.69 highways each with 52.0% creating none; this would equate to an estimated >120,000 across all registered Champions. In comparison, 6.1–29.8% of non-Champions stated that they had made a highway. However, most highways had been created in boundaries that could already be traversed via naturally occurring holes: only 11.4% of garden boundaries could be traversed, and 3.2% of gardens accessed, just via a hedgehog highway. In addition, only 5.0% of gardens were considered totally inaccessible to hedgehogs. The most common reasons cited for not having made a highway were that householders’ gardens were already accessible to hedgehogs followed by concerns relating to boundary ownership and / or communicating with neighbours. Future studies need to identify strategies for overcoming these obstacles to maximize citizen engagement, particularly with those householders who are not innately “wildlife-friendly”, and to quantify the degree to which networks of highways affect patterns of individual movement and, ultimately, populations.