bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Femtosecond Optical Parametric Generation in Group-Velocity-Matched MgO:PPLN at 10 MHz
Authors: Sukeert  , Pizzurro S. , Esteban-Martin A. , Gotti R. , Carrà L. , Piccinno G. , Agnesi A. , Pirzio F. , Kumar S. Chaitanya , Ebrahim-Zadeh M.
Published: March 2023

We report single-pass optical parametric generation of femtosecond pulses in the near- and mid-infrared with 58% average power conversion efficiency at 10 MHz repetition rate by exploiting group-velocity-matched interaction in a 42-mm-long MgO:PPLN crystal.
Widely tunable Solid State laser light source for precise time domain Coherent Raman measurements
Authors: Sylvester Jeremy , Neupane Chandra , Singhapurage Helani A. S. , Mudiyanselage Dinusha M.S.R. , Ganikhanov Feruz
Published: March 2023

We detail a lab-built femtosecond pulse solid-state source of laser-light with continuous tuning from 1030-1350 nm and resultant time-domain CARS measurements on KTP crystal with spectral resolution (<0.1 cm-1) and nearly 80 dB dynamic range.
Reduced Alignment Sensitivity and Pulsed Operation of Ho3+:YAG Laser Porro Resonators
Authors: Goth Katharina , Griesbeck Michael , Eitner Madeleine , Eichhorn Marc , Kieleck Christelle
Published: March 2023

We present a Ho3+:YAG laser resonator with two crossed Porro prisms showing an improved alignment stability by a factor of up to 200. In a length-optimized single-Porro- ended design, 60 ns long 0.8 mJ pulses are generated.
Real-Time High-Resolution Longwave IR Dual-Comb Spectroscopy Based on Cr:ZnS Laser Platform
Authors: Vasilyev Sergey , Muraviev Andrey , Konnov Dmitrii , Smolski Viktor , Peppers Jeremy , Mirov Mike , Moskalev Igor , Barnakov Yury , Vodopyanov Konstantin , Mirov Sergey
Published: March 2023

We report dual-comb spectroscopy with highly coherent broadband combs spanning 6– 12 µm produced via optical rectification of sub-three-cycle Cr:ZnS laser pulses. Real-time (~1sec) acquisition of broadband molecular spectra with the sub-Doppler resolution was demonstrated.
All passive Tm:YLF/KGW Raman Laser emit 1.1mJ at 2196nm
Authors: Gelbach Nachmen , Honig Menachem , Nahear Rotem , Noach Salman
Published: March 2023

All passive Tm:YLF/KGW Raman laser at 2196 and 2262 nm is presented. Pulse energy of 1.1mJ was achieved, the highest energy per pulse reported using KGW at the SWIR with high conversion efficiency of 33%.
Raman Combining of Fiber Lasers in the 1.55-μm Regime
Authors: Yu C. X. , Khitrov V. , P. Pax G. Allen , Messerly M. , Dawson J.
Published: March 2023

We successfully demonstrate Raman combination of fiber lasers in the 1.55-μm regime at the 100-W average power level. We achieved diffraction-limited 4.5-mJ, 2-ns pulses at 20 kHz PRF.
Comprehensive characterization of optical materials and coatings through direct absorption and scattered light measurements
Authors: Mühlig Ch. , Trost M. , Bublitz S.
Published: March 2023

Non-destructive assessment of sub-surface damage (SSD) by absorption and/or scatter loss detection is an attractive alternative to classic approaches like etching in order to evaluate the impact of polishing or figuring techniques on the laser induced damage (LIDT) behavior.
High Fidelity Replication of Two-Photon Polymerized Nanopatterned Tags via Molding Assisted Pattern Transfer
Authors: Jaiswal Arun , Rani Sweta , Singh Gaurav Pratap , Palwe Ajinkya , Saxena Sumit , Shukla Shobha
Published: March 2023

A sequential combination of two-photon lithography and molding process has been utilized to develop large-scale production of nanopatterned tags.
Narrow Linewidth, Filtered-Superfluorescent High Power Source with Linear Polarization
Authors: Koo Joonhoi , Kim Dong Joon , Jun Seung Won , Jeong Hwanseong , Lee Kwanghyun , Lee Jung Hwan , Jo Minsik
Published: March 2023

We investigate a linearly polarized superfluorescent(SFS) source using a 0.1 nm-filtered ASE of a semiconductor optical amplifier. The SFS source is amplified up to 2 kW by PM-fiberized amplifiers at 1065 nm region.
Applications of Polycrystalline YAG for LHPG Single Crystal YAG Fiber Lasers
Authors: Kim Hyunjun , Hay Randall S. , Averett Kent L. , Gibson Daniel J. , Schlup Andrew P. , Drazin John W. , Gray Benjamin A. , Corns Randall G. , Turner Robert E. , Bowers Cynthia T. , Doyle Kathryn M.
Published: March 2023

LHPG method is used to grow high optical quality single crystal fibers. For LHPG, polycrystalline ceramics can play important roles as feedstocks and cladding on the single crystal fibers.
Optical Properties of a Wedged Thin-Disk Amplifier
Authors: Ewers Benjamin , Augsburger Matthias , Sachs Lennert , Fischer Alexander , Lorbeer Raoul-Amadeus
Published: March 2023

Our wedged thin-disk laser introduces in-place multi-pass amplification with a simplified optical setup. This coincides with additional aberrations which are introduced by the asymmetric wedge geometry. We characterize our system aberrations in an amplifier configuration.
Thermal aberrations of higher-order OAM beams using compact end-pumped crystal rod MOPA’s
Authors: Harrison Justin , Forbes Andrew , Naidoo Darryl
Published: March 2023

For power scaling of twisted light carrying orbital angular momentum (OAM) of l = 2, the presence of vertical astigmatism in end-pumped MOPAs - due to asymmetric thermal aberrations - results in the separation of phase singularities.
Mid-IR Spectral and Laser Properties Comparison of Cr:ZnSe and Cr:Zn1-xMnxSe (x ≈ 0.05, 0.1, 0.2, 0.3) Single Crystals
Authors: Říha A. , Jelínková H. , Doroshenko M. E. , Němec M. , Šulc J. , Vyhlídal D. , Čech M. , Kovalenko N. O.
Published: March 2023

Temperature dependences of Cr2+ spectral and laser characteristics of Cr:ZnSe and Cr:Zn1-xMnxSe (x≈0.05, 0.1, 0.2, and 0.3) single crystals are compared and reported for ~1.73 μm laser excitation. Slope efficiency of ~44% at 78 K with pulse duration of ~140 ns was demonstrated.
Metasurface Dichroic Mirrors: Application to Low Quantum Defect Lasers
Authors: Georgiev Kaloyan , Kamali Khosro Zangeneh , Xu Lei , Rahmani Mohsen , Miroshnichenko Andrey , Neshev Dragomir , Buchvarov Ivan
Published: March 2023

We demonstrate the design and implementation of optical metasurface mirror with a steep spectral change of its reflection. Using it as a resonator pump mirror of an Yb-laser, stable operation is obtained without its damage.
Efficient Plasmonic Nanostructuring with Laser Annealing by Utilizing an Industrial Pulsed Fiber Laser Source
Authors: Ntemogiannis Dimitrios , Floropoulos Panagiotis , Karoutsos Vagelis , Poulopoulos Panagiotis , Alexandropoulos Dimitris
Published: March 2023

Plasmonic nanoparticles were grown via Laser annealing of silver ultrathin films by means of a pulsed fiber laser that enables efficient large scale plasmonic nanostructuring with high resolution patterning at the mm range.
Self-injection locking of two Fabry-Pérot laser diodes to a single integrated microresonator
Authors: Chermoshentsev Dmitry A. , Shitikov Artem E. , Lonshakov Evgeny A. , Grechko Georgy V. , Sazhina Ekaterina A. , Kondratiev Nikita M. , Masalov Anatoly V. , Bilenko Igor A. , Lvovsky Alexander I. , Ulanov Alexander E.
Published: March 2023

We investigate the dual-laser self-injection locking of two Fabry-Pérot laser diodes to different modes of an integrated Si3N4 microresonator. We observe different phenomena, like nonlinear interaction, simultaneous stabilization and coherent addition of output signal.
Enhanced Single-Frequency Lasing at 2.05 μm Based on a Highly Absorptive Tm/Ho-codoped Saturable Absorber
Authors: Zhang Lu , Sheng Quan , Zhang Junxiang , Fu Shijie , Shi Wei , Yao Jianquan
Published: March 2023

Using highly absorptive Tm/Ho-codoped fiber based saturable absorber to enhance the mode selection, a 2.05 μm single-frequency Tm-doped ring-cavity fiber laser with a record output power of over 200 mW is experimentally demonstrated.
Mid-infrared Er:YAP vortex laser
Authors: Gu Jie , Huang Lu , Zhou Wei , Ma Rui , Yao Weichao , Fan Dianyuan , Liu Jun
Published: March 2023

We demonstrate the direct generation of vortex beam in a mid-infrared Er:YAP laser with the annular pumping scheme. The operation wavelength can be switched from 2795 nm to 2921 nm by adjusting the pump power.
Compact opto-mechanical accelerometers for space applications
Authors: Sanjuan Jose , Guo Xiangyu , Hines Adam , Nelson Andrea , Valdes Guillermo , Wang Pengzhuo , Guzman Felipe
Published: March 2023

We present compact fused silica mechanical resonators paired with interferometric read-outs and highly-stable lasers to enable ultra-low noise accelerometry, which is key for space geodesy, inertial navigation, orbit determination, and planetary seismometry.
Investigation to the passively Q-switched laser analytical model with pump beam quality
Authors: Cho Chun-Yu , Shr Je-Hau , Lin Xin-Cheng
Published: March 2023

Modeling of PQS laser with spatial dependence is investigated to show that the threshold power will be significantly different when the pump beam quality was included. Energy scaling to millijoule is further demonstrated for verification.
Time-Frequency analysis of laser-produced underwater acoustic signals interaction across the water-air interface
Authors: Yellaiah J.
Published: March 2023

This study employs time-frequency analysis to visualize underwater acoustic signals (UAS) propagation and interaction across the water-air interface for experimental and numerical simulations. Experimentally acquired laser-generated UAS data was used as input for simulations.
Arterial pulsation modulates the optical attenuation coefficient of skin
Authors: Dominguez C. Tolentino , Martinelli M. Bigatão , Bachmann Luciano , Cardoso George C.
Published: March 2023

Photoplethysmographic (PPG) signals arise from the modulation of light reflectivity on the skin due to changes of physiological origin. Imaging plethysmography (iPPG) is a video-based PPG method that can remotely monitor vital signs in a non-invasive manner. iPPG signals result from skin reflectivity modulation. The origin of such reflectivity modulation is still a subject of debate. Here, we have used optical coherence tomography (OCT) imaging to find whether iPPG signals may result from skin optical properties being directly or indirectly modulated by arterial transmural pressure propagation. The light intensity across the tissue was modeled through a simple exponential decay (Beer–Lambert law) to analyze in vivo the modulation of the optical attenuation coefficient of the skin by arterial pulsation. The OCT transversal images were acquired from a forearm of three subjects in a pilot study. The results show that the optical attenuation coefficient of skin changes at the same frequency as the arterial pulsation due to transmural pressure propagation (local ballistographic effect), but we cannot discard the contribution of global ballistographic effects.
Mobile Lidar Scanning in Dynamic Urban Environments: Challenges and Applications
Authors: Hebel Marcus , Borgmann Björn , Gehrung Joachim , Arens Michael
Published: March 2023

We present recent research conducted with the lidar-equipped experimental vehicle MODISSA. Applications include real-time object detection and large-scale 3D mapping. We contribute our experiences and general thoughts on operating mobile lidar sensors in urban environments.
High-Definition Lidar 3D Sensing System
Authors: McMackin Lenore , Baca Christopher L. , Sage Gerald F. , Wong Rebecca , Hillard Jacob
Published: March 2023

We present results from a Lidar-based high definition 3D mapping system designed and built through optimization of a large software-controllable parameter space combining high throughput multi-channel optics with noise resistant digital encoding and processing.
Detection of the Orbital Angular Momentum State of Light using Sinusoidally-shaped Phase Grating
Authors: Dezfouli Ali Mardan , Abramović Denis , Rakić Mario , Skenderović Hrvoje
Published: March 2023

Using phase-only spatial light modulator a unique sinusoidally-shaped phased grating for efficient, robust and nearly alignment free detection of the orbital angular momentum (OAM) of optical vortices up to OAM=150 is demonstrated.
Full Spectral control in a One-Dimensional Solid State Random Laser
Authors: Kumar Bhupesh , Homri Ran , Sebbah Patrick
Published: March 2023

We report temperature-induced, narrow linewidth wavelength-tunable random lasing in 1D solid-state random laser. First, random laser is operated in a single-mode regime using the iterative pump optimization method. After that temperature-induced change in the refractive index of the PMMA-DCM layer leads to wavelength tunability.
Non-Redundant Array of Serpentine Optical Phased Array Beamsteering Tiles for 3-D Computational Lidar Imaging
Authors: Wagner K. , Dostart N. , Philbrick C. , Zhang B. , Brand M. , Feldkhun D. , Popović M.
Published: March 2023

A 2-dimensional non-redundant array of frequency-shifted beams transmitted by 2-D wavelength-beamsteering Si-photonic serpentine optical phased-array tiles interfere pairwise to produce traveling fringes. Detected backscatter probes the 3-D spatial Fourier components and enables Fourier synthetic-aperture LIDAR 3-D imaging of the illuminated target.
Nonlinear Self-Channeling of Ultrashort Pulses through Atmospheric Turbulence
Authors: Helle Michael H. , DiComo Gregory , Englesbe Alexander , Isaacs Joshua , Mamonau Aliaksandr , Kaganovich Dmitri , Fischer Richard , Peñano Joseph
Published: March 2023

We will present a comprehensive investigation of nonlinear self-channeling in atmospheric turbulence. In particular, experimental, theoretical and numerical results show the ability of a nonlinear self-channeling beam to resist turbulence-induced spreading and scintillation.
TARDIS Turbulence Profile Measurement Capability Summary and 2022 Data Collection Update
Authors: Zuraski Steven M. , McCrae Jack E. , Fiorino Steven T.
Published: March 2023

Long range imagery systems are negatively affected by atmospheric turbulence. This paper summarizes a novel method for quantifying that turbulence strength profile along the viewed path, and presents most recent data collection results
Tunable ultra-narrow linewidth diode laser for multiple metastable rare gas pumping
Authors: Han Jinliang , Zhang Jun , Shan Xiaonan , Peng Hangyu , Zhang Yawei , Qin Li , Wang Lijun
Published: March 2023

We present what we believe to be a novel external cavity feedback structure based on a double-layer laser diode array with volume Bragg grating (VBG). Diode laser collimation and external cavity feedback result in a high-power and ultra-narrow linewidth diode laser pumping source with a central wavelength of 811.292 nm, spectral linewidth of 0.052 nm, and output power exceeding 100 W, with external cavity feedback and electro-optical conversion efficiencies exceeding 90% and 46%, respectively. The temperature of VBG is controlled to tune the central wavelength from 811.292 nm to 811.613 nm, covering the Kr* and Ar* absorption spectra. We believe this is the first report of an ultra-narrow linewidth diode laser that can pump two metastable rare gases.
Controlling of the bidirectional amplifier chain for optical frequency distribution based on a two-dimensional noise detector
Authors: Krehlik Przemysław , Śliwczyński Łukasz , Turza Krzysztof , Salwik Karol , Buczek Łukasz
Published: March 2023

In the paper we present a solution for controlling the chain of bidirectional optical amplifiers, intended for long-haul fiber links used to distribute signals produced by optical atomic clocks. The solution is based on a dedicated two-channel noise detector, which allows independent measurement of the noise contributions related to interferometric signal fading and additive wideband noise. New signal quality metrics, based on two-dimensional noise detector, allows to distribute properly the needed gain among the chained amplifiers. Experimental results performed both in laboratory conditions and on a real 600 km-long link, confirming proper operation of proposed solutions, are presented.
Penrose tiling-inspired graphene-covered multiband terahertz metamaterial absorbers
Authors: Didari-Bader Azadeh , Saghaei Hamed
Published: March 2023

In this work, we propose two different graphene-covered nanostructured metamaterial absorbers inspired by Penrose tiling. These absorbers allow spectrally tunable absorption within the terahertz spectrum corresponding to 0.2-20 THz. We have conducted finite-difference time-domain analyses to determine the tunability of these metamaterial absorbers. The proposed structures, Penrose models 1 and 2, perform differently from each other due to their design characteristics. Penrose model 2 reaches a perfect absorption at 8.58 THz. In addition, the relative absorption bandwidth calculated at full-wave at half-maximum in Penrose model 2 varies between 5.2% and 9.4%, which characterizes the metamaterial absorber as a wideband absorber. Also, we can observe that as we increase the Fermi level of graphene from 0.1 to 1 eV, the absorption bandwidth and relative absorption bandwidth both increase. Our findings show the high tunability of both models through varying graphene’s Fermi level, the graphene’s thickness, the substrate’s refractive index, and the proposed structures’ polarization. We can further observe multiple tunable absorption profiles that may find applications in designer infrared absorbers, optoelectronic devices, and THz sensors.
On-axis deflectometric system for freeform surface measurement
Authors: Zhu Shengtai , Wang Daodang , Kang Wenjun , Liang Rongguang
Published: March 2023

We propose an on-axis deflectometric system for the accurate measurement of freeform surfaces with large slope ranges. A miniature plane mirror is attached on the illumination screen to fold the optical path and achieve the on-axis deflectometric testing. Due to the existence of the miniature folding mirror, the deep-learning method is applied to recover the missing surface data in a single measurement. Low sensitivity to the calibration error of system geometry and high testing accuracy can be achieved with the proposed system. The feasibility and accuracy of the proposed system have been validated. The system is low in cost and simple in configuration, and it provides a feasible way for the flexible and general testing of freeform surfaces, with a significant potential of the application in on-machine testing.
Diode-pumped visible lasing in femtosecond-laser-written Pr:LiLuF4 waveguide
Authors: Baiocco Davide , Lopez-Quintas Ignacio , Vázquez de Aldana Javier R. , Tonelli Mauro , Tredicucci Alessandro
Published: March 2023

In this Letter we report the realization of a femtosecond-laser-written diode-pumped Pr:LiLuF4 visible waveguide laser. The waveguide studied in this work consisted of a depressed-index cladding, whose design and fabrication were optimized to minimize the propagation loss. Laser emission has been achieved at 604 nm and 721 nm, with output power of 86 mW and 60 mW, respectively, and slope efficiencies of 16% and 14%. In addition, we obtained, for the first time in a praseodymium-based waveguide laser, stable continuous-wave laser operation at 698 nm (3 mW of output power and 0.46% of slope efficiency), corresponding to the wavelength necessary for the clock transition of the strontium-based atomic clock. The waveguide laser emission at this wavelength is mainly in the fundamental mode (i.e., the larger propagation constant mode) showing a nearly Gaussian intensity profile.
Experiments Showing Incompleteness of Wave Descriptions of Classical Wave Experiments
Authors: Peng Hui
Published: March 2023

Young’s double slit experiments revived the wave theory of light. The standard interpretation is that the light behaves as waves before and after passing through the double slit. Feynman called the double slit experiment the only mystery in quantum mechanics. In this article, we experimentally show the novel universal phenomena: (1) each of the fringes of the interference patterns are produced independently and partially; (2) within macro-distance from a diaphragm, the light rays behave as photons and produces a non-interference pattern; while near the screen, the photons produce an orthogonal interference pattern; (3) The non-interference pattern evolves to the orthogonal interference pattern gradually in the same experiment; (4) The non-interference patterns and the orthogonal interference patterns can show on the screen simultaneously; (5) The convex lens stops the further evolution. The experiments: (1) challenge the wave theories of light; (2) violate both Bohr’s complementarity principle and wave particle duality; (3) provide profound phenomena for developing optics and for studying the nature of light; (4) suggest that a complete theory should be able to consistently interpret all phenomena, including the non-interference pattern, the interference pattern, and the evolution from the non-interference to the interference pattern in the same experiment.
Structured illumination-based super-resolution live-cell quantitative FRET imaging
Authors: Luo Zewei , Wu Ge , Kong Mengting , Chen Zhi , Zhuang Zhengfei , Fan Junchao , Chen Tongsheng
Published: March 2023

Förster resonance energy transfer (FRET) microscopy provides unique insight into the functionality of biological systems via imaging the spatiotemporal interactions and functional state of proteins. Distinguishing FRET signals from sub-diffraction regions requires super-resolution (SR) FRET imaging, yet is challenging to achieve from living cells. Here, we present an SR FRET method named SIM-FRET that combines SR structured illumination microscopy (SIM) imaging and acceptor sensitized emission FRET imaging for live-cell quantitative SR FRET imaging. Leveraging the robust co-localization prior of donor and accepter during FRET, we devised a mask filtering approach to mitigate the impact of SIM reconstruction artifacts on quantitative FRET analysis. Compared to wide-field FRET imaging, SIM-FRET provides nearly twofold spatial resolution enhancement of FRET imaging at sub-second timescales and maintains the advantages of quantitative FRET analysis in vivo. We validate the resolution enhancement and quantitative analysis fidelity of SIM-FRET signals in both simulated FRET models and live-cell FRET-standard construct samples. Our method reveals the intricate structure of FRET signals, which are commonly distorted in conventional wide-field FRET imaging.
Synchronous climate hazards pose an increasing challenge to global coffee production
Authors: Richardson Doug , Kath Jarrod , Byrareddy Vivekananda M. , Monselesan Didier P. , Risbey James S. , Squire Dougal T. , Tozer Carly R.
Published: March 2023

Global coffee production is at risk from synchronous crop failures, characterised by widespread concurrent reductions in yield occurring in multiple countries at the same time. For other crops, previous studies have shown that synchronous failures can be forced by spatially compounding climate anomalies, which in turn may be driven by large-scale climate modes such as the El Niño Southern Oscillation (ENSO). We provide a systematic analysis of spatially compounding climate hazards relevant to global coffee production. We identify 12 climate hazards from the literature, and assess the extent to which these hazards occur and co-occur for the top 12 coffee producing regions globally. We find that the number of climate hazards and compound events has increased in every region between 1980 and 2020. Furthermore, a clear climate change signature is evident, as the type of hazard has shifted from overly cool conditions to overly warm. Spatially compounding hazards have become particularly common in the past decade, with only one of the six most hazardous years occurring before 2010. Our results suggest that ENSO is the primary mode in explaining annual compound event variability, both globally and regionally. El Niño-like sea-surface temperatures in the Pacific Ocean are associated with decreased precipitation and increased temperatures in most coffee regions, and with spatially compounding warm and dry events. This relationship is reversed for La Niña-like signatures. The Madden Julian Oscillation also shows a strong association with climate hazards to coffee, with increased activity in the Maritime Continent related to a global increase in the number of cold or wet hazards and a decrease in the number of warm or dry hazards. With climate change projections showing a continued rise in temperatures in the tropics is likely, we suggest that coffee production can expect ongoing systemic shocks in response to spatially compounding climate hazards.
Feasibility and usability of a very low-cost bubble continuous positive airway pressure device including oxygen blenders in a Ugandan level two newborn unit
Authors: Hedstrom Anna B. , Nyonyintono James , Saxon Eugene A. , Nakamura Heidi , Namakula Hilda , Niyonshaba Beatrice , Nakakande Josephine , Simpson Noelle , Vaughan Madeline , Wollen Alec , Mubiri Paul , Waiswa Peter , Coffey Patricia S. , Batra Maneesh
Published: March 2023

Background

Preterm birth and resulting respiratory failure is a leading cause of newborn death- the majority of which occur in resource-constrained settings and could be prevented with bubble continuous positive airway pressure (bCPAP). Commercialized devices are expensive, however, and sites commonly use improvised devices utilizing 100% oxygen which can cause blindness. To address this, PATH and a multidisciplinary team developed a very low-cost bCPAP device including fixed-ratio oxygen blenders.

Objective

We assessed feasibility of use of the device on neonatal patients as well as the usability and acceptability of the device by healthcare workers. This study did not evaluate device effectiveness.

Methods

The study took place in a Ugandan level two unit. Neonates with respiratory failure were treated with the bCPAP device. Prospective data were collected through observation as well as likert-style scales and interviews with healthcare workers. Data were analyzed using frequencies, means and standard deviation and interviews via a descriptive coding method. Retrospectively registered via ClinicalTrials.gov number NCT05462509.

Results

Fourteen neonates were treated with the bCPAP device in October—December 2021. Patients were born onsite (57%), with median weight of 1.3 kg (IQR 1–1.8). Median treatment length was 2.5 days (IQR 2–6). bCPAP was stopped due to: improvement (83%) and death (17%). All patients experienced episodes of saturations >95%. Median time for device set up: 15 minutes (IQR 12–18) and changing the blender: 15 seconds (IQR 12–27). After initial device use, 9 out of 9 nurses report the set-up as well as blender use was “easy” and their overall satisfaction with the device was 8.5/10 (IQR 6.5–9.5). Interview themes included the appreciation for the ability to administer less than 100% oxygen, desire to continue use of the device, and a desire for additional blenders.

Conclusions

In facilities otherwise using 100% oxygen, use of the bCPAP device including oxygen blenders is feasible and acceptable to healthcare workers.

Trial registration

ClinicalTrials.gov, Identifier NCT05462509.
Factors influencing the motivation of maternal health workers in conflict setting of Mogadishu, Somalia
Authors: Sheikh Naima Said , Gele Abdi
Published: March 2023

Motivated health workers play an important role in delivering high-quality maternal health services, especially in low-income countries where maternal mortality rates are high, and shortages of human resource for health is prevalent. The aim of this study is to investigate maternal health workers’ motivation in three tertiary hospitals in Mogadishu Somalia. We used a semi-structured questionnaire that was validated and widely used in Sub-Saharan Africa to collect data from 220 health workers across three tertiary hospitals in Mogadishu between February and April 2020. Health worker motivation was measured using seven constructs: general motivation, burnout, job satisfaction, intrinsic job satisfaction, organizational commitment, conscientiousness, timeliness and attendance. A multiple linear regression analysis was performed to determine the predictors of health worker motivation. The results show that male health workers have a higher work motivation, with a mean score of 92.75 (SD 21.31) versus 90.43 (SD 21.61) in women. As regards to profession, significant correlation was found between health workers’ motivation and being an assistant (coeff, 6.873, p = 0.001), nurse (coeff, 5.111, p = 0.000), physicians (coeff, 2.898 p = 0.042), pediatric assistants (coeff, 2.878, p = 0.048), midwife (coeff, 3.822, P = 0.01), and others (supervisor and pharmacist) (coeff, 5.623, P = 0.001). Unexpectedly, the gynecologists and midwives were the least motivated groups among the different professions, with mean scores of 83.63, (SD: 27.41) and 86.95 (SD: 21.08), respectively. Of the aforementioned seven motivation constructs, the highest mean motivation scores (from 1–5) were observed in conscientiousness and intrinsic job satisfaction. These results highlight the importance of targeted interventions that increase female health workers’ motivation, particularly gynecologists and midwives. This can be done by providing non-financial incentives, in addition to encouraging their participation in the decision-making process. Further research is needed to investigate the effect of a lack of motivation among gynecologists and midwives on maternal health in Somalia.
Immunogenicity and safety of concomitant and sequential administration of yellow fever YF-17D vaccine and tetravalent dengue vaccine candidate TAK-003: A phase 3 randomized, controlled study
Authors: Tricou Vianney , Essink Brandon , Ervin John E. , Turner Mark , Escudero Ian , Rauscher Martina , Brose Manja , Lefevre Inge , Borkowski Astrid , Wallace Derek
Published: March 2023

Background

Yellow fever (YF) vaccination is often mandatory for travelers to YF-endemic areas. The areas with risk of YF partially overlap with those of dengue, for which there is currently no recommended vaccine available for dengue-naïve individuals. This phase 3 study assessed the immunogenicity and safety of concomitant and sequential administration of YF (YF-17D) and tetravalent dengue (TAK-003) vaccines in healthy adults aged 18–60 years living in areas of the US non-endemic for either virus.

Methods

Participants were randomized 1:1:1 to receive the following vaccinations at Months 0, 3, and 6, respectively: YF-17D+placebo, TAK-003, and TAK-003 (Group 1); TAK-003+placebo, TAK-003, and YF-17D (Group 2); or YF-17D+TAK-003, TAK-003, and placebo (Group 3). The primary objective was to demonstrate non-inferiority (upper bound of 95% confidence interval [UB95%CI] of difference <5%) of YF seroprotection rate one month following concomitant administration of YF-17D and TAK-003 (Group 3) compared with YF-17D plus placebo (Group 1). The secondary objectives included demonstration of non-inferiority of YF and dengue geometric mean titers (GMTs) (UB95%CI for GMT ratio <2.0), and safety.

Results

900 adults were randomized. YF seroprotection rates one month post-YF-17D (Month 1) were 99.5% and 99.1% in Group 1 and 3, respectively, and non-inferiority was demonstrated (UB95%CI = 2.69% i.e. <5%). Non-inferiority was also demonstrated for GMTs against YF one month post-YF-17D, and against DENV-2, -3, and -4 (UB95%CI <2), but not DENV-1 (UB95%CI: 2.22), one month post-second TAK-003 vaccination. Adverse event rates following TAK-003 were consistent with previous results, and no important safety risks were identified.

Conclusions

In this study, YF-17D vaccine and TAK-003 were immunogenic and well tolerated when sequentially or concomitantly administered. The non-inferiority of immune responses to YF-17D and TAK-003 was demonstrated for concomitant administration of the 2 vaccines compared to separate vaccination, except against DENV-1 but with GMTs similar to those observed in other TAK-003 trials.

Trial registration

ClinicalTrials.gov identified: NCT03342898.
Knowledge and information sources towards Helicobacter pylori in Jordan
Authors: Alaridah Nader , F. Jarrar Raba’a , M. Joudeh Rayan , Aljarawen Mallak , Jum’ah Mohammad , Nassr Hasan , Riad AlHmoud Raad , Allouzi Abdullah , M. Wadi Eslam , H. A. Abu-Humaidan Anas
Published: March 2023

In 2017, the Jordanian Ministry of Health reported that gastric cancer was one of Jordan’s most diagnosed cancers. Gastric cancer is often linked toHelicobacter pylori, one of the foremost risk factors. Despite the high prevalence ofH.pyloriin Jordan, no information is available regarding the general population’s awareness of the harmful effects of this pathogen. The study aims to assess the knowledge and the impact of the source of knowledge onH.pyloriamong the general population in Jordan. A cross-sectional study involving 933 participants was conducted between May and July of 2021. After meeting the inclusion criteria and consenting to participate in this study, participants completed the questionnaire. An interview-based questionnaire covered the following sections: sociodemographic data and knowledge related toH.pyloriinfection. 63% of the participants had a high level of education, 70.5% got their information aboutH.pyloriinfection from non-medical sources, and 68.7% had a low level of knowledge. Working in the medical field, attaining information from medical resources, and having a history of self-reported or family member ofH.pyloriinfection showed a significant association with a high level of knowledge. The Mann-Whitney U test showed that the mean ranks of all knowledge items in the medical source group significantly exceed those of the non-medical source group (p-values < 0.05). In Jordan, the awareness ofH.pyloriwas unsatisfying, like in other countries. Nevertheless, misconceptions in knowledge aboutH.pyloriwere identified and further awareness must be spread and advocated. Close observation of the non-medical sources of information is essential for delivering sufficient amount of knowledge to the general population.
Revision of Potamobates Champion, 1898 (Hemiptera: Heteroptera: Gerridae) and description of a new genus for P. thomasi Hungerford, 1937
Authors: Floriano Carla Fernanda Burguez , Moreira Felipe Ferraz Figueiredo , Bispo Pitágoras da Conceição
Published: March 2023

Potamobates Champion, 1898 (Hemiptera: Heteroptera: Gerridae) heretofore included 18 species distributed from southern Mexico to Peru. They display a distinct morphology, especially regarding the projections of abdominal segment VIII. Specific identification and delimitation are difficult, and the genus lacks a thorough revision and evaluation of inter- and intraspecific variation. Here, we revise Potamobates, redescribe and/or illustrate known species, and describe P. molanoi Floriano and Moreira, sp. nov. and Brailovskybates Floriano and Moreira, gen. nov. The new genus is erected for P. thomasi Hungerford, 1937 and is characterized by the following features: (1) abdomen elongated, longer than the mesothorax; (2) abdominal spiracles positioned at the center of the segments; (3) male abdominal segment VIII without projections; (4) male pygophore and proctiger not rotated in relation to the longitudinal axis of the body; (5) female abdominal tergum VIII subequal in length and width; (6) and posterior margin of female abdominal sternum VII not produced medially, with a pair of lateral projections.
Medical students’ perception of resilience and of an innovative curriculum-based resilience skills building course: A participant-focused qualitative analysis
Authors: Nair Bhavana , Otaki Farah , Nair Avantika Fiza , Ho Samuel B.
Published: March 2023

Background

Medicine is one of the most demanding academic fields with an extensive curriculum that entails plenty of potential stressors. There is sufficient evidence that medical students are more prone to psychological distress when compared to their peer group of other disciplines. Despite the established need to prioritize resilience skills building within the medical curriculum, very few medical programmes in the Middle East and North Africa region (MENA) proactively empower the students to help themselves in sustaining their mental health. The purpose of the current study is to explore the perception of medical students in Dubai, United Arab Emirates (UAE) regarding their understanding of, and personal experience with building resilience, and their engagement with the content of an innovative curriculum-based resilience skills building course, designed in alignment with the constructivism theory of education.

Method

The current study utilized a qualitative phenomenological research design. The curriculum-based resilience skills building course, that was investigated as part of this study, is offered at a medical school in Dubai, UAE. A total of 37 students submitted reflective essays about resilience building, in general, and the respective course, in specific. The collected data was inductively analysed following a six-step framework.

Findings

The qualitative analysis generated three interlinked themes, namely: Awareness, Application, and Appraisal.

Conclusion

This study showed that integrating a resilience skills building course into medical curricula is likely to be positively appraised by the students, where it raises their level of awareness and likelihood of proactively applying the learned concepts in their daily lives. This is especially true when the course is anchored in constructivism experiential learning theory and designed to foster self-directed learning.
Opioid prescribing and social deprivation: A retrospective analysis of prescribing for CNCP in Liverpool CCG
Authors: Begley Emma K. , Poole Helen M. , Sumnall Harry R. , Frank Bernhard F. , Montgomery Catharine
Published: March 2023

Background

Treating Chronic Non-Cancer Pain (CNCP) with long-term, high dose and more potent opioids puts patients at increased risk of harm, whilst providing limited pain relief. Socially deprived areas mapped from Index of Multiple Deprivation (IMD) scores show higher rates of high dose, strong opioid prescribing compared to more affluent areas.

Objective

To explore if opioid prescribing is higher in more deprived areas of Liverpool (UK) and assess the incidence of high dose prescribing to improve clinical pathways for opioid weaning.

Design and setting

This retrospective observational study used primary care practice and patient level opioid prescribing data for N = 30,474 CNCP patients across Liverpool Clinical Commissioning Group (LCCG) between August 2016 and August 2018.

Method

A Defined Daily Dose (DDD) was calculated for each patient prescribed opioids. DDD was converted into a Morphine Equivalent Dose (MED) and patients stratified according to high (≥120mg) MED cut off. The association between prescribing and deprivation was analysed by linking GP practice codes and IMD scores across LCCG.

Results

3.5% of patients were prescribed an average dose above 120mg MED/day. Patients prescribed long-term, high dose, strong opioids were more likely to be female, aged 60+, prescribed three opioids and reside in the North of Liverpool where there is a higher density of areas in the IMD most deprived deciles.

Conclusion

A small but significant proportion of CNCP patients across Liverpool are currently prescribed opioids above the recommended dose threshold of 120mg MED. Identification of fentanyl as a contributor to high dose prescribing resulted in changes to prescribing practice, and reports from NHS pain clinics that fewer patients require tapering from fentanyl. In conclusion, higher rates of high dose opioid prescribing continue to be evident in more socially deprived areas further increasing health inequalities.
Computational modeling of human multisensory spatial representation by a neural architecture
Authors: Domenici Nicola , Sanguineti Valentina , Morerio Pietro , Campus Claudio , Del Bue Alessio , Gori Monica , Murino Vittorio
Published: March 2023

Our brain constantly combines sensory information in unitary percept to build coherent representations of the environment. Even though this process could appear smooth, integrating sensory inputs from various sensory modalities must overcome several computational issues, such as recoding and statistical inferences problems. Following these assumptions, we developed a neural architecture replicating humans’ ability to use audiovisual spatial representations. We considered the well-known ventriloquist illusion as a benchmark to evaluate its phenomenological plausibility. Our model closely replicated human perceptual behavior, proving a truthful approximation of the brain’s ability to develop audiovisual spatial representations. Considering its ability to model audiovisual performance in a spatial localization task, we release our model in conjunction with the dataset we recorded for its validation. We believe it will be a powerful tool to model and better understand multisensory integration processes in experimental and rehabilitation environments.
Movement ecology of diploid and triploid grass carp in a large reservoir and upstream tributaries
Authors: Hessler Tyler M. , Chapman Duane C. , Paukert Craig P. , Jolley Jeffrey C. , Byrne Michael E.
Published: March 2023

Grass carp Ctenopharyngodon idella, is an herbivorous fish originally brought to North America from Asia in 1963 to control nuisance aquatic vegetation. Since their arrival, detrimental alterations to aquatic ecosystems have sometimes occurred in waterways where they were initially stocked and into which they have escaped. The movements of grass carp from lentic systems into tributaries required for spawning is poorly understood, and understanding environmental conditions associated with upstream migrations may aid in management of the species. We stocked 43 fertile diploid and 43 sterile triploid grass carp implanted with acoustic transmitters into Truman Reservoir, Missouri, USA between January 2017 and October 2018 to characterize movements during spring and summer when spawning conditions occur. Twenty fish (11 diploid/9 triploid) exhibited upstream migration behavior in the Osage River, a major tributary, in 2018 and 2019. Migration primarily occurred in April and May, during high discharge events associated with increasing river stage when water temperatures were between 15 and 28°C. Observed migrations ranged from 3.0–108 river km in length, and six individuals were observed making multiple upstream migrations in one season. Eleven fish initiated upstream migrations while in the lentic main body of the reservoir. These findings provide some evidence for upstream migrations by diploid and triploid grass carp as well both lake and river residents. Evidence of similar upstream migration behavior by both diploid and triploid grass carp suggests that triploids may be suitable surrogates for diploids for study of movement ecology. Removal efforts in tributaries targeting periods of increasing river stage during spring may provide the best opportunity of encountering large concentrations of grass carp.
Associations of 5-year changes in alcoholic beverage intake with 5-year changes in waist circumference and BMI in the Coronary Artery Risk Development in Young Adults (CARDIA) study
Authors: Butler J. Lauren , Gordon-Larsen Penny , Steffen Lyn M. , Shikany James M. , Jacobs David R. , Popkin Barry M. , Poti Jennifer M.
Published: March 2023

Objective

This study aimed to shed light on contradictory associations of alcohol intake with waist circumference (WC) and body mass index (BMI) by examining 5-yr changes in alcohol intake in relation to 5-yr WC and BMI changes.

Methods

This prospective study included 4,355 participants (1,974 men and 2,381 women) enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study at baseline (1985–1986) and followed over 25 years (2010–2011). Longitudinal random effects linear regression models were used to test whether changes in drinking (defined categorically) as starting to drink, increasing, decreasing, stable drinking or stopping drinking (versus stable non-drinking) over a series of 5-yr periods were associated with corresponding 5-yr WC and BMI changes. Associations with 5-yr changes (defined categorically as starting, stable or stopping) in drinking level (i.e., light/moderate and excessive) and 5-yr changes (defined categorically as increasing, no change, or decreasing) by beverage type (i.e., beer, wine and liquor/mixed drinks) were also examined.

Results

In men, compared to stable non-drinking, decreasing total alcohol intake was associated with lower 5-yr WC (β:-0.62 cm; 95% CI: -1.09, -0.14 cm) and BMI gains (β:-0.20 kg/m2; 95% CI: -0.30, -0.03 kg/m2) and stopping excessive drinking was associated with lower 5-yr WC gains (β:-0.77 cm; 95% CI: -1.51, -0.03 cm). In women, compared to those with stable non-drinking habits, starting light/moderate drinking was associated with lower 5-yr WC (β: -0.78 cm; 95% CI: -1.29, -0.26 cm) and BMI gains (β:-0.42 kg/m2; 95% CI: -0.64, -0.20 kg/m2). Increasing wine intake was associated with a lower 5-yr BMI gain (β:-0.27 kg/m2; 95% CI: -0.51, -0.03 kg/m2). Decreasing liquor/mixed drink (β:-0.33 kg/m2; 95% CI: -0.56, -0.09 kg/m2) intake was associated with lower 5-yr WC (β:-0.88 cm; 95% CI: -1.43, -0.34 cm) and BMI (β:-0.33 kg/m2; 95% CI: -0.56, -0.09 kg/m2) gains.

Conclusions

Associations of alcohol intake with obesity measures are complex. In women, wine and liquor/mixed drink intakes had contrasting associations with WC and BMI change. In men, decreasing weekly alcoholic beverage intake with an emphasis on stopping excessive consumption may be beneficial in managing WC and BMI gains.
The effects of sociocultural changes on epistemic thinking across three generations in Romania
Authors: Ionescu Amalia , Furdui Raluca , Gavreliuc Alin , Greenfield Patricia M. , Weinstock Michael
Published: March 2023

When people experience abrupt social change, from less education to more, from less technology use to more, from a homogeneous to a heterogeneous social environment, can their epistemic thinking adapt? When divergent opinions suddenly come to be valued, does epistemic thinking shift from absolute to more relativistic? We investigate whether and how these sociocultural shifts have produced changes in epistemic thinking in Romania, a country that fell from communism and started democracy in 1989. Our 147 participants were from Timisoara and fell into three groups, each experiencing the shift at a different point in their development: (i) born in 1989 or later, experiencing capitalism and democracy throughout life (N = 51); (ii) 15- to 25-years-old in 1989 when communism fell (N = 52); (iii) 45 or older in 1989 when communism fell (N = 44). As hypothesized, absolutist thinking was less frequent and evaluativist thinking, a relativistic epistemological mode, was more frequent the earlier in life a cohort was exposed to the post-communist environment in Romania. As predicted, younger cohorts experienced greater exposure to education, social media, and international travel. Greater exposure to education and social media were significant factors in the decline of absolutist thinking and the rise of evaluativist thinking across the generations.