bluuebunny/crossref_metadata_2025 huggingface dataset:
Nano Tweaks to Ultrafast Non-Equilibrium Dynamics
Authors: Dai Linjie , Greenham Neil C
Published: December 2024

Understanding and control of ultrafast non-equilibrium processes in semiconductors are key to leveraging quantum states. Here, we demonstrate the manipulation of interactions between carriers, phonons, and spins using quantum confinement and symmetry breaking through nanomorphology.
Bioplastic Diffraction Gratings Fabricated from Crab Shells: Performance at Varying Chitosan Concentrations
Authors: Gumayan Efren G. , Dimzon Ian Ken D. , Guerrero Raphael A.
Published: December 2024

We report the diffraction performance of bioplastic diffraction gratings fabricated from crab shell waste. Soft lithography is employed to fabricate grating replicas with different chitosan concentrations. First-order output from diffraction experiments confirms the fidelity of the replication process. Diffraction efficiencies are comparable with values obtained from grating replicas based on silicone.
Femtosecond Laser Ablated blind-Holes by Different Micromachining Parameters in Solid Oxide Fuel Cells
Authors: Baba Mohamed A. , Lemieszek Bartlomiej , Sriubas Mantas , Khatmi Gazy , Abakevičienė Brigita , Tamulevičius Sigitas , Molin Sebastian , Tamulevičius Tomas
Published: December 2024

To meet expectations for sustainable technology, The efficacy of solid
oxide fuel cell (SOFC) induced by femtosecond laser micromachining. A
scanning electron microscope and impedance electrochemical
spectroscopy assessed the SOFC. The structured cell performed 18
percent superior to the reference cell.
OAM degree of coherence
Authors: Pokharel Sushil , Korotkova Olga
Published: December 2024

A new scalar quantity, Orbital Angular Momentum (OAM) Degree of Coherence (DOC), is introduced to characterize radial correlations in a random beam among various OAM modes, in similarity with previously introduced EM DOC.
Hot Atoms and Light Cooperating
Authors: Hensley Hagan , Larsen Braden , Thompson James K.
Published: December 2024

Here we demonstrate a limited-infrastructure cavity QED platform by probing transits of thermal Rb atoms through a narrow optical cavity. We detail our progress towards resolving single-atom transits and creating a non-classical source of light.
Exploration of Soliton Rain and Bound-State Soliton Regimes in MXene-Coated EDF Fiber Lasers
Authors: Diachenko Radomyr , Lee Kwanil
Published: December 2024

This research explores unconventional regimes like soliton rain and bound-state soliton in EDF fiber lasers with MXene-coated etched optical fibers, aiming for ultrafast pulse generation and high repetition rates.
Evidencing the Hanle Effect with Polarization Spectroscopy for the D2 Line of Cesium
Authors: Jiménez Gabriel , Mejía Jose , Portela Mayerlin Núñez
Published: December 2024

Hanle effect is evidenced in a polarization spectroscopy scheme for the cesium D2 line. The effect is observed in the anisotropy signal for the F = 4 → F′ = 5 hyperfine transition. Results are promising for applications in quantum magnetometry.
Simulating Solar Eclipse Shadow Bands Utilizing a Spatial Light Modulator
Authors: Conry Jessica , Harrington Amber
Published: December 2024

This study simulates shadow bands observed during solar eclipses using a low-power HeNe laser, a null mask, and a phase mask displayed on a spatial light modulator, replicating atmospheric conditions in a controlled laboratory environment.
A Study on Axial Resolution Improvement Using Wiener Filter in SS-OCT Based Digital Photonic Sensor
Authors: Yamauchi Takanori , Sono Naoki , Goto Hiroki , Shirahata Takuma , Kotake Nobuki
Published: December 2024

In this research, we improved the axial resolution of a non-contact ranging system using a swept-source optical sensor and Wiener filter, traditionally applied in radar signal processing, and examined the wavelength dependency of the resolution.
Enhanced zero-phonon line emission from an ensemble of W centers in circular Bragg grating cavities
Authors: Veetil Vijin Kizhake , Ebadollahi Nikki , Song Junyeob , Katzenmeyer Aaron M. , Namboodiri Pradeep N. , Pomeroy Joshua M. , Davanco Marcelo , Srinivasan Kartik , Pelton Matthew
Published: December 2024

We fabricated circular Bragg grating cavities containing an ensemble of silicon color centers. For cavities whose modes are resonant with the zero-phonon line emission of the color centers, we observed a 5.5-fold enhancement in the emitted intensity combined with a 1.3-fold increase in the decay rate.
Laser Beam Interaction With Rough Surfaces: a New Tool to Simulate Dynamic Laser Speckle
Authors: Tonti Filippo , Moresco Michele , Miglio Andrea
Published: December 2024

Analyzing speckle interference patterns generated by laser illumination on rough or contaminated surfaces poses challenges for advanced optical systems. We introduce an algorithm to simulate static and dynamic speckle phenomena, critical for optimizing optical performance.
Probing the Oxidation levels of Low-Density Lipoprotein Using the Z-scan Technique
Authors: Abu-Safe Husam H.
Published: December 2024

The oxidation levels of low-density lipoprotein (LDL) using the z-scan method was investigated. The LDL samples were oxidized using copper sulfate. The amplitude of the z-scan signal modeled the changes in the oxidization levels.
Combining HHG with an RF Frequency Comb Generator for High Frequency (>60 GHz), Element-Specific Spectroscopy
Authors: Tanksalvala Michael , Kos Anthony , Wisser Jacob , Diddams Scott , Nembach Hans T , Shaw Justin M
Published: December 2024

We have developed a tabletop-scale instrument to perform element-specific spectroscopic studies, such as x-ray detected ferromagnetic resonance spectroscopy, at high frequencies (>60 GHz) by combining an RF frequency comb generator with a high-harmonic generation source.
A Coherent and Efficient One-Dimensional Atom
Authors: Javadi Alisa , Tomm Natasha , Antoniadis Nadia O. , Janovitch Marcelo , Brunelli Matteo , Schott Rudiger , Valentin Sascha R. , Wieck Andreas D. , Ludwig Arne , Potts Patrick P. , Warburton Richard J.
Published: December 2024

We achieve 99.2% extinction in cavity transmission using a quantum dot, enabling optical nonlinearities at the fundamental limit, between two photons. We observe a g2(0) = 587 for transmitted photons, the strongest reported to date.
A microscope for observing intracellular transport with molecular resolution on molecular timescales
Authors: Axelrod Jeremy J. , Marti G. Edward , Chu Steven
Published: December 2024

We demonstrate an optical microscope that localizes gold nanoparticles to under 1 nm in 10 µs with illumination conditions compatible with live cell imaging. This enables molecular-scale measurements of molecular motor dynamics in intracellular transport.
Simulating Quantum State Revival with Paraxial Beam Propagation
Authors: Khatiwada Pawan , Yu Daniel , Yu Edward , Qian Xiao-Feng
Published: December 2024

We explore the equivalence between paraxial optical beam propagation and 2D harmonic oscillator evolution. The phenomenon of quantum state revival of harmonic oscillator is shown to be simulated with the propagation of a focusing beam.
Impact of pressure on the magnetocaloric effect in InSb quantum wire: Rashba SOI and crossed electromagnetic field
Authors: Priyanka  , Sharma Rinku
Published: December 2024

The impact of hydrostatic pressure on the magnetocaloric effect in an InSb quantum wire has been investigated. First, eigenenergies are obtained using the diagonalization method, then entropy and magnetic entropy (magnetocaloric effect) are calculated numerically.
High Efficiency Inverse-Designed Grating Coupler in a Suspended Gallium Arsenide Platform
Authors: Granmoe Austin , Sun Shuo
Published: December 2024

In this talk, I will present our recent simulation results that showcase an inverse-designed grating coupler in a suspended gallium arsenide (GaAs) platform that achieves higher coupling efficiencies than state-of-the-art.
Generation of temperature-insensitive polarization-entangled photon pairs in a single-domain crystal
Authors: Chin Jia Boon , Prato Diane , Ling Alexander
Published: December 2024

Noncritical Birefringent Phasematched Type-II Spontaneous Parametric Downconversion in single-domain KTiOPO4 was used to generate temperature-insensitive polarization-entangled photon pairs. The idler wavelength drifted by 10nm and entanglement visibility remained > 95% over a temperature change of 70°C.
Europium-Doped Niobate-Based Phosphors for Enhanced Red Emission in Phosphor-Converted White LEDs
Authors: Poria Kanishk , Deopa Nisha , Shahi Jangvir Singh
Published: December 2024

Europium-doped niobate-based phosphors were synthesized via solid-state reaction, exhibiting promising luminescent properties. These phosphors demonstrate efficient red emission under near-UV/blue excitation, making them strong candidates for enhancing color rendering in white LEDs.
Electrically Tunable SERS Substrate Using Gold Nanopyramids on Graphene
Authors: Portes Ary V. R. , Teixeira Felipe M. F. , Marques Talles E. M. , Ramirez Jhonattan C.
Published: December 2024

This work presents electrically tunable SERS devices, consisting of gold nanopyramids on a graphene-coated dielectric substrate. Simulations reveal significant improvements in absorbance and precise modulation of field enhancement, offering promising avenues for biosensing applications.
Exploration of the Hong-Ou-Mandel Effect with Cavity QED Single-photon Sources
Authors: McCollum Caden , Dudones Lexi , Mirza Imran
Published: December 2024

We use the quantum jump approach to study two-photon interference effects with cavity quantum electrodynamics (cQED) single photon sources arranged against a 50-50 beam splitter.
Fiber Optic Interferometer Estimating Conditions of the Measured Metal Surfaces
Authors: Rychert Karolina , Sokołowski Patryk , Łubiński Jacek
Published: December 2024

The research aims to explore the potential of fiber optic distance measurement through reflected light analysis on surfaces from real-life machine contacts, including stainless steel. Conducted measurements enable the evaluation of abrasion of machine components. Range of mesurments was 10 to 500 um making fiber optic an ideal method of measurment.
Development of a High-Speed Light Scattering Measurement Technique for Analyzing Light Field Imaging of a Single Microparticle
Authors: Shigyo Kazuki , Ito Yusuke , Imaki Masaharu , Kotake Nobuki
Published: December 2024

We introduce a novel method to measure angular scattering of light from microparticles at high speeds using a lens-array, enabling light field measurements without mechanical scanning, and improving efficiency and accuracy.
Fourier-Domain Mode-Locked Laser-Based Depth-Resolved Vibrometry Indicates Involvement of Superficial Hair in the Sound Detection of Snapping Shrimp
Authors: Spellauge Tillmann , Bonesi Marco , Shepherd Jami , Radford Craig A. , Vanholsbeeck Frédérique
Published: December 2024

We present a Depth-resolved vibrometry system using a Fourier-domain mode-locked laser based optical coherence tomography system. We further present the first measurements of mechanical responses of snapping shrimp superficial hair to acoustic particle motion stimuli.
A Novel Deep Learning Framework for Enhanced Acute Lymphoblastic Leukemia Detection
Authors: Ahmadsaidulu Shaik , Kanase Akash Suresh , Jain Puneet Kumar , Banoth Earu
Published: December 2024

In this work a deep-learning model using enhanced YOLOv8(You Only Look Once) for classifying Acute Lymphoblastic Leukemia (ALL) and other normal cells. Achieving 98% accuracy for ALL and 91% for combined (ALL & Normal) classification enhances clinical decision-making.
Ultra-low Loss Highly Multi-mode Hollow-core Anti-resonant Fiber Designs
Authors: Al Mahfuz Mohammad , Habib Md Selim
Published: December 2024

We present a next-generation ultra-low loss highly multi-mode hollow-core anti-resonant fiber design with strong-inhibited mode-coupling properties. The fiber supports >50 distinct spatial modes with losses under 100 dB/km.
Temporal entanglement and wavepacket shaping based on the interference of two photons through a beam splitter
Authors: Tian Zhaohua , Liu Qi , Tian Yu , Gu Ying
Published: December 2024

We analytically study the interference of two photons with different temporal shapes through a beam splitter (BS), then propose its application in temporal entanglement and shaping of photons
Bi-chromatic Intensity Squeezing at Telecom Wavelength using Four-Wave Mixing in Rb Vapor
Authors: Niu Ziqi , Wen Jianming , Zhang Chuanwei , Du Shengwang , Novikova Irina
Published: December 2024

We optimized four-wave mixing gain in a double-ladder system in Rb vapor, and observed more than 2dB of two-mode intensity squeezing between amplified 795nm probe and generated 1324nm conjugate optical fields.
Achieving High-Fidelity Bell States Through Interferometric Short-Pulsed Laser Techniques
Authors: Tomis  , Narayanan V.
Published: December 2024

We present a method for creating Bell states by an interferometric approach with a short-pulsed laser. A Bell state was created by type-II spontaneous parametric down-conversion (SPDC), achieving a fidelity and visibility close to ~ 90%.
Collinear Optical 2D Coherent Spectroscopy with 5-kHz Repetition Rate Femtosecond Laser
Authors: Revesz Stephen , Gatamov Rustam , Misiara Adolfo , Li Hebin
Published: December 2024

We demonstrate optical two-dimensional coherent spectroscopy in a collinear geometry on rubidium vapor with time-integrated fluorescence detection using a low-repetition rate femtosecond laser for both excitation and as reference with a pulse shaper.
Spectral and Temporal Characteristization of UV Resonant Dispersive Waves
Authors: Kincaid Chelsea , Kaufman Brian , Allum Felix , Godínez José , Britton Mathew , Bain Matthew , Chini Michael , Forbes Ruaridh , Larsen Kirk A.
Published: December 2024

Using rare gas-filled hollow-core-fibers we generate tunable UV pulses with bandwidths that support few-cycle duration via Resonant Dispersive Wave emission, which are temporally compressed and characterized using a home-built SD-FROG, demonstrating few-femtosecond pulse widths.
Magneto-Optical Effects in NaGdF4 Nanorods
Authors: Esmaeili Shahriar , Rajil Navid , Hazrathosseini Ayla , Yi Zhenhuan , Hemmer Philip , Scully Marlan
Published: December 2024

Exploring the magneto-optical effects of NaGdF4:Yb/Er nanorods, this study employs hydrothermal synthesis and polarized light to unveil the potential of these nanoparticles in advanced sensing and optical device applications.
Portable lensfree imaging platform based on prior-guided phase retrieval
Authors: Zheng Shenghao , Guo Cheng
Published: December 2024

We presented a portable lensfree imaging platform that can achieve complex wavefield reconstruction with multi-distance intensity measurements. In our platform, 400 LEGO bricks and a bare CMOS sensor chip are integrated into a lensfree in-line holographic imaging system, where a motor and a set of gear modules from LEGO are designed to control the axial movement of a sample to generate multi-plane intensity patterns. In data processing, the intensity images are calculated in a computer to show the retrieved amplitude and phase of the sample. In addition, we propose a prior-guided phase retrieval algorithm to realize a data-efficient recovery, where only two intensity images are required to perform high-fidelity imaging performance. Experimental results of different kinds of samples are given to prove the effectiveness of our platform. We believe that our portable lensfree platform will provide a low-cost DIY microscope for hands-on science experiments.
Enabling Precision Astronomical Spectroscopy with Laser Frequency Combs
Authors: Fredrick Connor
Published: December 2024

We describe the design and long-term performance of the 30 GHz optical frequency comb used as the primary calibration source of the Habitable Zone Planet Finder (HPF) spectrograph, a system used for one of the most demanding spectroscopic applications in astronomy, the detection of planets beyond our solar system through Doppler spectroscopy.
Quantum-Enhanced Two Photon Interactions Beyond the Photon Pairs Regime
Authors: Dickinson T. , Afxenti I. , Astrauskaite G. , Hirsch L. , Nerenberg S. , Jedrkiewicz O. , Gatti A. , Faccio D. , Müllenbroich C. , Clerici M. , Caspani L.
Published: December 2024

Quantum-enhanced two-photon interactions driven by parametric down-conversion (PDC) were mainly investigated in the photon pairs regime. We report the observation of nonclassical effects in the stimulated PDC regime, beyond the standard one-photon-per-mode threshold.
Single-Photon Source in Silicon Nitride Photonics for Quantum Key Distribution
Authors: Senichev Alexander , Martin Zachariah O. , Peana Samuel , Lagutchev Alexei S. , Boltasseva Alexandra , Shalaev Vladimir M.
Published: December 2024

We present an evaluation of quantum emitters formed at the interface of nitrogen-rich silicon nitride and silicon dioxide, demonstrating their potential as single-photon sources for quantum photonic applications, focusing on polarization-based quantum key distribution.
Utilizing light-matter re-coupling to enhance and control the superfluorescence in a semiconductor overdamped ring microcavity
Authors: Cao Beibei , Li Hantao , Dong Chengwei , Liu Wenyuan , Jin Jingjing , Jie Qi
Published: December 2024

In this paper, we study the propagation and time-evolution behavior of superfluorescence in an overdamped semiconductor ring microcavity. By introducing a re-coupling mechanism between the unidirectionally propagating superfluorescence and the cooperative exciton state with a specified Gaussian spatial distribution, we can compress the width of the photoluminescence (PL) pulse in both temporal and spatial scales. Using realistic parameters from perovskite superlattice materials, we observe that the maximum intensity increases twofold compared to the ordinary radiation behavior observed in planar microcavity systems. This offers an alternative approach to achieving the desired PL. By controlling the excitation density distribution, the dissipation rate, and the length of the ring cavity, we can manipulate the spatial position and the corresponding temporal evolution of the PL pulse at micrometer and picosecond scales, which holds significant potential for various applications.
In situ characterization of two unknown ultrashort laser pulses using four-wave mixing in gas
Authors: Nambu Noa , Nie Zan , Marsh Ken , Joshi Chan
Published: December 2024

Accurate characterization of two ultrashort laser pulses is of great interest in many ultrafast pump-probe experiments. We demonstrate a method based on four-wave mixing (FWM) in a gas which could be easily implemented into many existing pump-probe setups with minimal modifications for accurate, in situ characterization of both unknown pulses. This technique is tested on pairs of unknown pulses at wavelengths of 400/800 nm, and 266/400 nm. We measured the spectrogram of the pulse generated through FWM of the two unknown pulses by scanning the delay between two unknown pulses. The retrieval algorithm converges to accurately predict the intensity and the phase profiles of both unknown pulses with a trace error of < 1% and the accuracy is verified using an independent pulse characterization device.
InGaAs/GaAs metamorphic buffer for laser power converter applications
Authors: Pan Huadong , Wang Jun , Chen Xiangliu , Chen Yongji , Mou Zhiqiang , Yang Huomu , Deng Guoliang , Gou Yudan
Published: December 2024

This paper investigated the optimization of InGaAs/GaAs metamorphic buffer and its application to LPCs (laser power converters). Firstly, InGaAs (18%) metamorphic buffer with step (S), step + overshoot (SO), step + reverse (SR), and step + reverse + overshoot (SRO) structures were investigated by X-ray, AFM and TEM, respectively. Moreover, an InGaAs (24%) SRO buffer structure with a relaxation of 94.5% and a surface roughness of 5.4 nm were obtained. Further, 1064 nm InGaAs metamorphic LPCs were grown and fabricated on InGaAs (24%) SRO buffer with an efficiency of 44.2%, and the reliability of these metamorphic LPCs was demonstrated by operating it at 190°C for 1174 hours.
Angle-insensitive broadband transparent microwave absorber with high shielding effectiveness
Authors: Wu Yanghui , Fu Chen , Jiang Yutong , Bian Jing , Gu Wenhua
Published: December 2024

In this work, a specially designed multilayer indium tin oxide (ITO) mesh structure metasurface was proposed as a microwave absorber, achieving both excellent angle-insensitive broadband absorption and high shielding effectiveness (SE). It features gradually changing surface resistance (Rs), to expand the absorption bandwidth while maintaining high SE. Also, a folded square ring metasurface was designed to effectively suppress surface wave grating lobes, as well as to reduce the unit size of the metasurface and thus the absorber. What is more, an additional top dielectric layer was used to stabilize the absorption and SE under an oblique incidence condition (≤45°). As a result, an ultra-broadband miniaturized transparent absorber was realized, with an absorption of >80% in a 2.10–14.65 GHz frequency band (150% relative bandwidth) and a SE of >20 dB in 1–12 GHz at normal incident. The relative thickness of the absorber is only ∼0.117λ0, and the unit size of the metasurface is only 0.083λ0. The broadband absorption mechanism of the multilayer absorber was analyzed from the aspects of resonance frequency, surface current distribution, and equivalent circuit. In general, the proposed absorber showed angle-insensitive ultra-wideband absorption with high SE at the same time, implying a wide range of applications.
Observation of complete energy transfer by orthogonally polarized Raman scattering in a high-birefringence fiber
Authors: Hao Qiang , Liu Yang , Li Xuexue , Luo Peng , Zeng Heping
Published: December 2024

This study reports the observation of complete orthogonally polarized Raman scattering (OPRS) in a 1.0-km high-birefringence fiber (HBF). An incident pump pulse at 1560 nm with an energy of 2.48 nJ and a duration of less than 100 fs is aligned along the slow axis of the HBF. Initially, the incident pump pulse generates a Raman soliton and experiences soliton self-frequency shift (SSFS) along the slow axis. When the energy of the incident pump pulse reaches 0.74 nJ, the Raman soliton in the slow axis induces and amplifies a new, to the best of our knowledge, spectral component referred to as generated pulse in the fast axis through OPRS. Subsequently, the two orthogonally polarized pulses trap each other through cross-phase modulation, temporally overlap, and copropagate along the fiber until the energy of the Raman soliton in the slow axis is depleted. Finally, the generated pulse in the fast axis autonomously undergoes the SSFS process, extending beyond 1770 nm. Notably, the second OPRS process is observed as the energy of the incident pump pulse reaches 1.55 nJ.
Polarization-insensitive and compact single-mode filter on a 340 nm silicon-on-insulator platform
Authors: Wen Chengfeng , Liu Weixi , Song Lijia , Li Huan , Dai Daoxin , Shi Yaocheng
Published: December 2024

In this paper, we propose and demonstrate an integrated polarization-insensitive single-mode filter (SMF) on a 340 nm silicon-on-insulator (SOI) platform, by introducing two lateral coupling waveguides to couple high-order modes from central single-mode waveguide to lateral waveguides. The experimental results show that the excess loss is <0.29 dB and the extinction ratio is >20 dB with a broad bandwidth of 136 nm for the fabricated SMF with a compact footprint of <13 µm.
Continuously tunable low-loss phase shifter using weak-dispersion spoof surface plasmon polaritons
Authors: Fan Yi , He Pei Hang , Liu Yiwen , Zhang Hao Chi , Cui Tie Jun
Published: December 2024

We propose a continuously tunable low-loss phase shifter based on weak-dispersion spoof surface plasmon polariton (SSPP) waveguide. Unlike traditional designs of SSPP devices that rely on the strong-dispersion property, we address the high insertion loss issue by leveraging the weak-dispersion region of SSPP. A detailed study reveals the relation between the waveguide length, phase shift, and insertion loss of SSPP. Based on the weak-dispersion SSPP structure, we design an active SSPP unit by integrating a varactor to tune the phase continuously. Experimental results show that continuous phase shifts up to 258° are achieved with an insertion loss less than 0.016 dB per degree at the designed frequency of 8.5 GHz. Compared to the traditional phase shifters, the proposed design exhibits significant performance.
Adaptive decorrelation compensation approach in digital-image-correlation-assisted phase-sensitive optical coherence tomography
Authors: Dong Bo , Bai Yulei , He Zhaoshui , Xie Shengli
Published: December 2024

This work demonstrates that the phase-based decorrelation compensation method outperforms the amplitude-based approach in low signal-to-noise ratio (SNR) regions of phase-sensitive optical coherence tomography (PhS-OCT). Building on this finding, an adaptive decorrelation compensation approach for digital-image-correlation (DIC)-assisted PhS-OCT is introduced. This method utilizes the maximum correlation coefficient from amplitude maps to adaptively determine the need for secondary tracking of decorrelated displacement using the phase-based approach. It significantly improves decorrelation compensation quality while minimizing impacts on computational efficiency. A tensile testing experiment was conducted to validate the method, with results showing that the proposed adaptive compensation method enables previously unmeasurable low SNR regions to become measurable by adaptively retracking only 21.7% of the area.
Long distance calls: Negligible information loss of little auk social vocalisations due to high frequency propagation losses
Authors: Osiecka Anna N. , Bryndza Przemysław , Briefer Elodie F. , Wojczulanis-Jakubas Katarzyna
Published: December 2024

How well does the information contained in vocal signals travel through the environment? To assess the efficiency of information transfer in little auk (Alle alle, an Arctic seabird) calls over distance, we selected two of the social call types with the highest potential for individuality coding. Using available recordings of known individuals, we calculated the apparent source levels, with apparent maximum peak sound pressure level (ASPL) of 63 dB re 20 μPa at 1 m for both call types. Further, we created a sound attenuation model using meteorological data collected in the vicinity of the little auk colony in Hornsund, Spitsbergen. Using this model, we modelled the calls to reflect higher frequency filtering and sound level loss occurring during spherical spreading in perfect local conditions, down to the putative hearing threshold of the species, calculated to equal ASPL of signals “propagated” to roughly one kilometre. Those modelled calls were then used in a permuted discriminant function analysis, support vector machine models, and linear models of Beecher’s information statistic, to investigate whether transmission loss will affect the retention of individual information of the signal. Calls could be correctly classified to individuals above chance level independently of the distance, down to and over the putative physiological hearing threshold. Interestingly, the information capacity of the signal did not decrease with its filtering and attenuation. While this study touches on signal properties purely and cannot provide evidence of the actual use by the animals, it shows that little auk signals can theoretically travel long distances with negligible information loss, and supports the hypothesis that vocalisations could facilitate long-distance communication in the species.
Cost-effectiveness of comparative survey designs for helminth control programs: Post-hoc cost analysis and modelling of the Kenyan national school-based deworming program
Authors: Minnery Mark , Okoyo Collins , Morgan Grace , Wang Andrew , Johnson Olatunji , Fronterre Claudio , Montresor Antonio , Campbell Suzy J. , Mwandawiro Charles , Diggle Peter
Published: December 2024

Background

Soil-transmitted helminths (STH) and schistosomiasis comprise the most wide-spread NTDs globally. Preventative chemotherapy is a cost-effective approach to controlling morbidity of both diseases, but relies on large scale surveys to determine and revise treatment frequency. Availability of detailed information on survey costs is limited despite recent methodological surveying innovations. We micro-costed a survey of STH and schistosomiasis in Kenya, and linked results to precision estimates of competing survey methods to compare cost-efficiency.

Methods

Costs from a 2017 Kenyan parasitological survey were retrospectively analyzed and extrapolated to explore marginal changes when altering survey size, defined by the number of schools sampled and the number of samples taken per school. Subsequent costs were applied to simulated precision estimates of model-based geostatistical (MBG) and traditional survey designs. Cost-precision was calculated for a range of survey sizes per method. Four traditional survey design scenarios, based around WHO guidelines, were selected to act as reference cases for calculating incremental cost-effectiveness ratios (ICERs) for MBG design.

Findings

MBG designed surveys showed improved cost-precision, particularly if optimizing number of schools against samples per school. MBG was found to be more cost-effective under 87 of 92 comparisons to reference cases. This comprised 14 situations where MBG was both cheaper and more precise, 42 which had cost saving with precision trade off (ICERs; $8,915-$344,932 per percentage precision lost); and 31 more precise with increased cost (ICERs; $426-$147,748 per percentage precision gained). The remaining 5 comparisons represented extremes of MBG simulated site selection, unlikely to be applied in practice.

Interpretation

Efficiency gains are possible for deworming surveys when considering cost alone, such as through minimizing sample or analysis costs. However further efficiency maximization is possible when designing surveys using MBG given its improved precision and ability to optimize the balance between number of schools and sample size per school.
Dose-response effects of multiple Ascaris suum exposures and their impact on lung protection during larval ascariasis
Authors: Amorim Chiara Cássia Oliveira , Nogueira Denise Silva , Gazzinelli-Guimarães Ana Clara , Leal-Silva Thais , Barbosa Fernando Sérgio , Oliveira Fabrício Marcus Silva , Kraemer Lucas Rocha , de Almeida Raquel Martins , Souza Jorge Lucas Nascimento , Dias Magalhães Luisa Mourão , Russo Remo Castro , Caliari Marcelo Vidigal , Gaze Soraya , Bueno Lilian Lacerda , Fujiwara Ricardo Toshio
Published: December 2024

Background

Human ascariasis is the most prevalent geohelminthiasis worldwide, affecting approximately 446 million individuals. In regions with endemic prevalence, the majority of infected adults are frequently exposed to the parasite and tend to have a low parasite load. Further studies are necessary to provide more evidence on the dynamics of infection and to elucidate the possible mechanisms involved in regulating protection, especially during the acute phase, also known as larval ascariasis. The aim of this study is to compare the impact of lung function between single and multiple infections in a murine model.

Methods

We infected BALB/c mice considering the frequency of exposures: single-exposure—SI; twice-exposures—RE 2x and thrice-exposures—RE 3x, and considering the doses of infection: 25 eggs—RE 25; 250 eggs—RE 250 and 2,500 eggs—RE 2500, followed by infection challenge with 2,500 eggs. From this, we evaluated: parasite burden in lungs, cellular and humoral response, histopathological and physiological alterations in lungs.

Results

The main results showed a reduction of parasite burden in the reinfected groups compared to the single-infected group, with protection increasing with higher exposure and dose. Furthermore, the RE 250 group exhibited a decrease of parasite burden close to RE 2500, but with less tissue damage, displaying the most favorable prognosis among the reinfected groups.

Conclusion

Our research indicates a dose-dependent relationship between antibody production and the intensity of the immune response required to regulate the parasite burden.
Mathematical modelling to estimate the impact of maternal and perinatal healthcare services and interventions on health in sub-Saharan Africa: A scoping review
Authors: Collins Joseph H. , Cambiano Valentina , Phillips Andrew N. , Colbourn Tim
Published: December 2024

Introduction

Mathematical modelling is a commonly utilised tool to predict the impact of policy on health outcomes globally. Given the persistently high levels of maternal and perinatal morbidity and mortality in sub-Saharan Africa, mathematical modelling is a potentially valuable tool to guide strategic planning for health and improve outcomes.

Methods

The aim of this scoping review was to explore the characteristics of mathematical models and modelling studies evaluating the impact of maternal and/or perinatal healthcare interventions or services on health-related outcomes in the region. A search across three databases was conducted on 2nd November 2023 which returned 8660 potentially relevant studies, from which 60 were included in the final review. Characteristics of these studies, the interventions which were evaluated, the models utilised, and the analyses conducted were extracted and summarised.

Results

Findings suggest that the popularity of modelling within this field is increasing over time with most studies published after 2015 and that population-based, deterministic, linear models were most frequently utilised, with the Lives Saved Tool being applied in over half of the reviewed studies (n = 34, 57%). Much less frequently (n = 6) models utilising system-thinking approaches, such as individual-based modelling or systems dynamics modelling, were developed and applied. Models were most applied to estimate the impact of interventions or services on maternal mortality (n = 34, 57%) or neonatal mortality outcomes (n = 39, 65%) with maternal morbidity (n = 4, 7%) and neonatal morbidity (n = 6, 10%) outcomes and stillbirth reported on much less often (n = 14, 23%).

Discussion

Going forward, given that healthcare delivery systems have long been identified as complex adaptive systems, modellers may consider the advantages of applying systems-thinking approaches to evaluate the impact of maternal and perinatal health policy. Such approaches allow for a more realistic and explicit representation of the systems- and individual- level factors which impact the effectiveness of interventions delivered within health systems.
Applying a cytochrome c oxidase I barcode for Leishmania species typing
Authors: Mata-Somarribas Carlos , Cardoso das Graças Grazielle , de Oliveira R. Pereira Luiza , Côrtes Boité Mariana , Motta Cantanhêde Lilian , Braga Filgueira Camila Patrício , Fallas Adrián , Quirós-Rojas Leana , Morelli Karina A. , Ferreira Gabriel Eduardo Melim , Cupolillo Elisa
Published: December 2024

Species delimitation has always been a challenge for taxonomists and for Leishmania studies there is no exception. Herein we attempt to display the usefulness of the mitochondrial gene Cytochrome Oxidase I–coI in classical and barcode-based approaches for Leishmania characterization. A total of 228 samples were analyzed, comprising 28 Leishmania related taxa, mainly from cultures of the Oswaldo Cruz Foundation`s Leishmania Collection. Primers were designed for amplification of coI; sequences were analyzed by distance-based indicators and both the Neighbor Joining and NeighborNet as species grouping techniques. Automatic Barcode Gap Discovery was applied to define species delimitation while for the character-based analysis a software for Barcoding with Logic formulas was employed. Final sequences of 486 bp with 238 parsimonious sites were aligned and edited. Robust groups were formed for most of the genus species, distinctive nucleotide positions in the barcode sequence were observed for 11 of them. A good agreement between the techniques applied and the original characterization was observed. Few species were not distinguished by coI: (i) L. (V.) peruviana, L. (V.) lindenbergi, and L. (V.) utingensis; (ii) L. (L.) venezuelensis and (iii) L. colombiensis and L. equatorensis with identical sequences. Some of these taxa have been, at one time or another, classified as controversial and, for most of them, a higher number of isolates should be studied to properly infer their taxonomic status. CoI represents a mitochondrial target that stands out as a taxonomically important asset with multiple advantages over other genes. This paper corresponds to the first report of coI analysis in Leishmania, a potentially advantageous target for the characterization of this parasite.
Needle in a haystack: Harnessing AI in drug patent searches and prediction
Authors: Ribeiro Leonardo Costa , Muzaka Valbona
Published: December 2024

The classification codes granted by patent offices are useful instruments for simplifying the bewildering variety of patents in existence. They are singularly unhelpful, however, in locating a specific subgroup of patents such as that of drug-related pharmaceutical patents for which no classification codes exist. Taking advantage of advances in artificial intelligence and in natural language processing in particular, we offer a new method of identifying chemical drug-related patents in this article. The aim is primarily that of demonstrating how the proverbial needle in a haystack was identified, namely through leveraging the superb pattern-recognition abilities of the BERT (Bidirectional Encoder Representations from Transformers) algorithm. We build three different databases to train our algorithm and fine-tune its abilities to identify the patent group in question by exposing it to additional texts containing structures that are much more likely to be present in them, until we obtain the highest possible F1-score, combined with an accuracy of 94.40%. We also demonstrate some possible uses of the algorithm. Its application to the US patent office database enables the identification of potential chemical drug patents up to ten years before drug approval, whereas its application to the German patent office reveals the regional nature of drug R&D and patenting strategies. The hope is that both the method proposed and its applications will be further refined and expanded forthwith.
Resinous included phloem as a key indicator of authentic or fake agarwood
Authors: Feng Jian , Liu Yangyang , Liu Peiwei , Yang Yun , Xie Anzhen , Wei Jianhe
Published: December 2024

Agarwood, the resinous wood of the genus Aquilaria Lam. and Gyrinops Gaertn. of the family Thymelaeaceae, is a very valuable traditional medicinal material and spice. Due to the high economic value of agarwood, unscrupulous merchants have led to the prevalence of fake agarwood in the trade market in pursuit of high profits. Therefore, it is crucial to explore the characteristics of agarwood and establish a simple and rapid method to identify authenticity. This study compared the authenticity of the microstructure of agarwood from different producing areas with that of artificially simulated fake agarwood. The included phloem of authentic agarwood contains brown to brownish resin. And these resins were naturally and stably distributed. The fake agarwood is divided into two categories: one itself is non-agarwood wood (without included phloem), and the other is artificially counterfeiting. However, the filling of resin in the included phloem of agarwood did not occur after artificially simulated counterfeiting treatments. Of the 18 commercially available samples, 10 had the same microstructure as agarwood, but six of them were not completely filled with resin in the included phloem. Therefore, the resinous included phloem is a key characteristic structure of agarwood. It can be used as a basis for authenticity identification of agarwood. This will provide a convenient and rapid method for promoting and popularizing agarwood authentication in trade, customs enforcement, CITES management, and other fields.
Randomized controlled trial of a pilot PrEP linkage intervention for individuals leaving incarceration in a southern state: Design and baseline characteristics
Authors: Horton Heather , Marshall S. Alexandra , Gu Mofan , Tody Brooklyn , Jackson Timikia , Zaller Nick
Published: December 2024

Objective

We report baseline characteristics of a pilot intervention, PrEP-Link, which uses a community health worker (CHW) model to provide navigation to PrEP, the daily HIV preventative medication, and other medical and social services upon release from incarceration.

Trial design and methods

This pilot study uses a randomized controlled trial design. The control group receives enhanced standard of care, and the intervention receives enhanced standard of care plus personalized navigation services from the CHW for up to one year. PrEP-Link is modeled after the Transitions Clinic Program, where a CHW who has lived experience of incarceration builds close relationships with individuals and community partners. After COVID-19 restrictions prevented recruitment within local jails, recruitment for this study took place in local reentry centers which house individuals as they near completion of their jail or prison sentence. Data are collected at baseline, 6 months, and 12 months. Planning and reporting was guided by the CONSORT 2010 checklist.

Results

We enrolled 80 participants between September 2021 and April 2023. Thirty-nine participants were assigned to the control group and forty-one to the intervention group. Data collected at baseline included measures of PrEP usage, HIV risk, drug and alcohol use, healthcare usage, and history of incarceration. Analysis of baseline characteristics show comparability of both demographic and HIV-related risk factors between the two arms.

Conclusions

At baseline, participants had high clinical indication for potential PrEP benefit, particularly with respect to self-reported intravenous drug use and condomless sex. Participants responded with high PrEP acceptability within both study arms. Participants reported low preventative healthcare utilization at baseline. Barriers to accessing PrEP among the study population are significant. Results of this pilot RTC will help inform CHW lead PrEP-linkage interventions for people leaving incarceration.
High-throughput Kinetics using capillary Electrophoresis and Robotics (HiKER) platform used to study T7, T3, and Sp6 RNA polymerase misincorporation
Authors: Carter Zachariah I. , O’Brien William B. , Lund Sean , Gardner Andrew F.
Published: December 2024

T7 RNA Polymerase (RNAP) is a widely used enzyme with recent applications in the production of RNA vaccines. For over 50 years denaturing sequencing gels have been used as key analysis tools for probing the nucleotide addition mechanisms of T7 RNAP and other polymerases. However, sequencing gels are low-throughput limiting their utility for comprehensive enzyme analysis. Here, we report the development of HiKER; (High-throughput Kinetics using Capillary Electrophoresis and Robotics) a high-throughput pipeline to quantitatively measure enzyme kinetics. We adapted a traditional polymerase misincorporation assay for fluorescent detection at scale allowing rapid estimates of RNAP misincorporation in different experimental conditions. Using this platform with an OT-2 robotics system, ~1500 time points were collected in a single workday. T7 RNAP exhibited dramatic differences in both observed rate constant and amplitude depending on the mismatch examined. An average misincorporation frequency of ~45 misincorporations per million bases was estimated using HiKER and is consistent with previous studies. Misincorporation time courses for T3 RNAP and Sp6 RNAP were also collected and appeared similar to T7 RNAP suggesting conserved kinetic mechanisms. However, differences between the RNAPs were observed in extension from base mismatch experiments. This platform is affordable, open-source, and broadly applicable to many enzymes.
Instant prediction of scientific paper cited potential based on semantic and metadata features: Taking artificial intelligence field as an example
Authors: Zhu Hou , Shuhuai Li
Published: December 2024

With the continuous increase in the number of academic researchers, the volume of scientific papers is also increasing rapidly. The challenge of identifying papers with greater potential academic impact from this large pool has received increasing attention. The citation frequency of a paper is often used as an objective indicator to gauge the academic influence of the paper. The task of citation frequency prediction based on historical citation data in previous studies can achieve high accuracy. However, it can only be executed after the paper has been published for a period. The delay is not conducive to timely discovery of papers with high citation frequency. In this paper, we propose a novel method for predicting cited potential of a paper based on the metadata and semantic information, which can predict the cited potential of academic paper instantly once it has been published. Specifically, the semantic information, such as abstract, semantic span and semantic inflection, is extracted to enhance the ability of the prediction model based on machine learning. To prove the effectiveness and rationality of cited potential prediction model, we conduct two experiments to validate the model and find the most effective combination of input information. The empirical experiments show that the prediction accuracy of our proposed model can reach 88% for the instant prediction of citation.
Prevalence and severity of alopecia lesions on gray bats, Myotis grisescens, peaks during lactation
Authors: Cable Ashleigh B. , Kinsella Megan , Gerhold Richard , Hamrick Elizabeth , Holliday Cory , Ogle Chris , Stinson II Robert T. , Thames Dustin , Willcox Emma V.
Published: December 2024

We observed multiple gray bats (Myotis grisescens) in 2022 with large patches of fur loss (i.e., alopecia) on the dorsal surface of their body. Alopecia in wildlife has been linked to multiple possible factors and often is a sign of suboptimal health. In 2023, we designed an experiment to compare prevalence of alopecia in gray bats across various reproductive stages, characterize the severity of alopecia lesions, and determine the ectoparasites and microbiota present on the regions of fur loss. We harp-trapped four summer gray bat roosts 2–3 times between 11 April–30 August 2023 and collected skin swabs and scrapes from each bat with alopecia. We determined the severity of the alopecia lesions on a scale 0–7 by summing the degree of redness (0–2), skin condition (0–1), and percentage of fur loss (0–4). We cultured the skin swabs for fungal and bacterial growth and examined skin scrapes under a microscope to determine the presence of subcutaneous mites. We found no evidence that subcutaneous mites cause the fur loss. We determined that prevalence of alopecia in M. grisescens varies throughout the summer. Prevalence is highest for female bats that are or recently were lactating, reaching an average of 6% ± 6 SD (0–15% range) of captured females exhibiting fur loss during the pup rearing period. Alopecia is most prevalent in male bats in early summer (1% ± 2 SD; 0–4% range). Lactating females had more severe cases than males and were often associated with skin redness due to unknown causes. Bats with alopecia did not differ in body condition, determined from body mass, from bats without alopecia. Future studies could investigate the role of stress in possible autoimmune responses contributing to alopecia. Conservation strategies aimed at reducing stress and supporting nutritional requirements during the summer are likely beneficial to M. grisescens.