bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of CLT in Promoting Learner Autonomy in English Language Classrooms: A Case Study on Bangladeshi Tertiary Education
Authors: Fuad A.F.M Sadman Sakib
Published: May 2023

Exploratory in nature, this study aims to discover how CLT is interconnected with learner autonomy and whether it effectively propagates autonomy in tertiary-level ELT classrooms of Bangladesh. A mixed-method approach is followed to conduct this research. Two separate sets of questionnaires have been developed and distributed among the tertiary teachers and students to collect the quantitative data. Additionally, the qualitative data is extracted from the semi-structured interviews of the tertiary students. The major findings of this current study conclude with four essential themes: collaborative learning, teachers’ role in tertiary CLT classrooms, autonomous learners, and freedom of learning with CLT. Moreover, the detailed analysis of these themes evaluates Bangladeshi tertiary students’ stance on CLT and affirms that CLT is quite sufficiently promoting learner autonomy in tertiary ELT classes. At last, the study concludes with a set of recommendations for tertiary teachers so that they can be more efficient in replicating CLT methods in language classrooms to ensure the everlasting display of autonomy.
Effect of Moringa Leaves Ethanolic Extract (Moringa oleifera, Lam.) on Testicles Histopathological Structure in Metabolic Syndrome Rat Model
Authors: Aji Febriagi Bayu , Setyawan Novan Adi , Hakim Fikar Arsyad , Pesik Riza Novierta
Published: May 2023

Introduction: Metabolic syndrome was a collection of various disorders that can significantly increase the risk of experiencing insulin resistance, atherosclerotic cardiovascular disease, vascular complications, and diabetes mellitus. The detrimental effect of this condition has led to the development of various treatments options, such as Moringa leaves extract (Moringa oleifera), which was suspected to have ameliorative effects. Therefore, this study aimed to determine the effect of Moringa leaves extract on the histopathological appearance of the testes of Wistar rats induced with metabolic syndrome.

Methods: This was an experimental design study, with a post-test-only control group, involving 30 Wistar rats (Rattus norvegicus). Metabolic syndrome was induced in the samples through the administration of high-fat and fructose feeds along with streptozotocin and nicotinamide. Furthermore, the moringa leaves extract was administered to the treatment groups in different doses of 150, 250, and 350 mg/kg BW. Testicular histopathological damage scores were then assessed on each group. The Kruskal-Wallis test which followed by Mann-Whitney test was used to determine the significant differences between the groups, while the correlation was analyzed using Spearman test.

Results: There were significant differences in the histopathological scores between the treatment and control groups. Furthermore, the Wistar rats treated with Moringa extract showed better histopathological scores (2.1±0.64) compared to those without the treatment (2.7±0.54), p<0.05. The results also showed that higher doses of the extract significantly correlated with better outcome in testicular histopathological structure of metabolic syndrome rat model (p=0.000, r=-0.396).

Conclusion: Moringa leaves ethanolic extract treatment improved testicular histopathological appearance in Wistar rats induced with metabolic syndrome.
The impact of self-reinforcing and self-undermining policy feedback on Mexican social policy: the end of the conditional cash transfer programme
Authors: Ramírez Viviana , Velázquez Leyer Ricardo
Published: May 2023

The conditional cash transfer programme (CCT) for poor families was terminated in Mexico in 2019. CCTs seek to fight poverty under a social investment logic by promoting the formation of human capital through the compliance of behavioural conditionalities. The programme – the first of its kind introduced at national level – accomplished several achievements and was maintained and developed by three successive federal administrations. As the backbone of anti-poverty policy for more than two decades, its achievements included delivering positive results to a significant proportion of the population; and triggering the expansion of social policy beyond social insurance. As a result, it was emulated by governments across the globe. A programme of these characteristics would have been expected to generate path dependency and policy stability, yet it was swiftly terminated with practically no opposition. This article applies a framework of historical institutionalism to analyse the feedback effects developed during the duration of the programme from the perspectives of beneficiaries, in order to contribute to the explanation of its termination. The research is based on qualitative empirical data from interviews with former beneficiaries. Our findings show that self-undermining mechanisms linked to a ‘hard’ design and implementation of conditionalities counterbalanced the self-reinforcing mechanisms derived from the benefits supplied by the programme, causing beneficiaries to become apathetic towards its continuity or termination. Conclusions yield theoretical insights that might serve to examine policy feedback in similar contexts, as well as lessons for policymakers regarding the design and implementation of social programmes.
3 kW forward-pumped fiber laser via pump recycler
Authors: Lin Weixuan , Bussières-Hersir Marie-Hélène , Auger Mathieu , Vincelette André , Rochette Martin
Published: May 2023

We report a single-end forward-pumped fiber laser with a record high
output power of 3 kW. The laser is assembled exclusively from
commercially widespread components such as the Yb-doped fiber with
core/cladding diameter of 20/400 µm, pump laser diodes at an
emission wavelength of 915 nm, and a signal and pump fiber
combiner that serves as the pump recycler. The record high power
arises from the combination of the 915 nm pumping and pump
recycler with an effective reflectivity of 78%, increasing
simultaneously the thresholds for stimulated Raman scattering and
transverse mode instability (TMI). The length of the oscillator was
also varied experimentally from 20 m to 5 m, showing a
contrast of up to 19% in the TMI threshold. This shows the importance
of accurately partitioning the Yb-doped fiber length in between the
oscillator and amplifier sections to minimize the impact of TMI.
Few-mode erbium-doped fiber with trench and weak coupling for mode gain equalization based on layered-doping technology
Authors: Zhao Qi , Tang Jianjun , Xie Yuheng , Feng Lipeng , Dou Tianqi
Published: May 2023

A few-mode erbium-doped fiber (FM-EDF) with a step refractive index and
trench structure is designed and proposed to realize the modal gain
equalization of a few-mode erbium-doped fiber amplifier (FM-EDFA). The
layered-doping technology is used to reduce the mode gain difference
(DMG). The doping radius and doping concentration are adjusted to
obtain the optimum FM-EDF structure. When the designed FM-EDF is
applied to the FM-EDFA, the DMG of the whole C-band is less than
0.15 dB and the DMG is less than 0.12 dB at
1550 nm. The minimum refractive index difference (Δneff) between modes can be calculated
according to the refractive index and radius of the fiber core; i.e., 1.35×10−3, which will greatly reduce the
coupling between modes in a practical application. Tolerances in the
fiber manufacturing process are also considered for reliable FM-EDFA
performance. When the doping radius and concentration of each doping
layer fluctuate by ±15% based on the precise value, the
maximum DMG increases to 1.8 dB. In general, DMG can maintain a
small value, which is beneficial for application in optical
communications systems.
Quantitative phase-amplitude surface determination in reflection differential interference contrast profilometry
Authors: Postnikov A. V.
Published: May 2023

An approach for measuring the surface profile of the samples with
reflection variations using the Nomarski differential interference
method is presented. The system is analyzed with Jones’s matrices
tool, and polarization effects of a non-polarizing beam splitter are
taken into account. Equations are also developed to allow the
determination of the surface profile from interference intensity when
the sample reflectively is not uniform. The validity and accuracy of
the measurement are verified by measuring the adhered silicon
cantilever on a substrate with high reflectivity. This
method is expected to be a valuable tool to inspect elements of
micromechanics and microsystems.
Impact of experimental setup parameters on the measurement of articular cartilage optical properties in the visible and short near-infrared spectral bands
Authors: Kafian-Attari Iman , Nippolainen Ervin , Bergmann Florian , Mirhashemi Arash , Paakkari Petri , Foschum Florian , Kienle Alwin , Töyräs Juha , Afara Isaac O.
Published: May 2023

There is increasing research on the potential application of diffuse optical spectroscopy and hyperspectral imaging for characterizing the health of the connective tissues, such as articular cartilage, during joint surgery. These optical techniques facilitate the rapid and objective diagnostic assessment of the tissue, thus providing unprecedented information toward optimal treatment strategy. Adaption of optical techniques for diagnostic assessment of musculoskeletal disorders, including osteoarthritis, requires precise determination of the optical properties of connective tissues such as articular cartilage. As every indirect method of tissue optical properties estimation consists of a measurement step followed by a computational analysis step, there are parameters associated with these steps that could influence the estimated values of the optical properties. In this study, we report the absorption and reduced scattering coefficients of articular cartilage in the spectral band of 400-1400 nm. We assess the impact of the experimental setup parameters, including surrounding medium, sample volume, and scattering anisotropy factor on the reported optical properties. Our results suggest that the absorption coefficient of articular cartilage is sensitive to the variation in the surrounding medium, whereas its reduced scattering coefficient is invariant to the experimental setup parameters.
Tunable plasmonic tweezers based on graphene nano-taper for nano-bio-particles manipulation: numerical study
Authors: Khorami Ali Asghar , Barahimi Behdad , Vatani Sare , Javanmard Athar Sadat
Published: May 2023

We take advantage of graphene nano-taper plasmons to design tunable plasmonic tweezers for neuroblastoma extracellular vesicles manipulation. It consists of Si/SiO2/Graphene stack topped by a microfluidic chamber. Using plasmons of isosceles-triangle-shaped graphene nano-taper with a resonance frequency of 6.25 THz, the proposed device can efficiently trap the nanoparticles. The plasmons of graphene nano-taper generate a large field intensity in the deep sub-wavelength area around the vertices of the triangle. We show that by engineering the dimensions of the graphene nano-taper and an appropriate choice of its Fermi energy, the desired near-field gradient force for trapping can be generated under relatively low-intensity illumination of the THz source when the nanoparticles are placed near the front vertex of the nano-taper. Our results show that the designed system with graphene nano-taper of L = 1200 nm length and W = 600 nm base size and THz source intensity of I = 2 mW/µm2, can trap polystyrene nanoparticles with diameters of D = 140, 73, and 54 nm, and with trap stiffnesses of ky = 9.9 fN/nm, ky = 23.77 fN/nm, and ky = 35.51 fN/nm at Fermi energies of Ef = 0.4, 0.5, and 0.6 eV, respectively. It is well known that the plasmonic tweezer as a high-precision and non-contact means of control has potential applications in biology. Our investigations demonstrate that the proposed tweezing device with L = 1200 nm, W = 600 nm, and Ef = 0.6 eV can be utilized to manipulate the nano-bio-specimens. So that, at the given source intensity, it can trap the neuroblastoma extracellular vesicles, which are released by neuroblastoma cells and play an important role in modulating the function of neuroblastoma cells and other cell populations, as small as 88 nm at the front tip of isosceles-triangle-shaped graphene nano-taper. The trap stiffness for the given neuroblastoma extracellular vesicle is obtained as ky = 17.92 fN/nm.
Microscopy with heralded Fock states
Authors: Gieysztor Maria , Nepinak Joshua , Pugh Christopher J. , Kolenderski Piotr
Published: May 2023

We consider a microscopy setting where quantum light is used for illumination. Spontaneous parametric down conversion (SPDC) is used as a source of a heralded single photon, which is quantum light prepared in a Fock state. We present analytical formulas for the spatial mode tracking along with the heralded and non-heralded mode widths. The obtained analytical results are supported by numerical calculations and the following discussion taking into account realistic setup parameters such as finite-size optics and finite-size single-photon detectors. This allows us to observe that the diffraction limit can be approached with simultaneous alleviation of the photon loss leading to increased signal-to-noise ratio – a factor limiting practical applications of quantum light. Additionally, it is shown that the spatial resolution can be manipulated by carefully preparing the amplitude and phase of the spatial mode profile of the single photon at the input to the microscope objective. Here, the spatial entanglement of the biphoton wavefunction or adaptive optics can be applied for spatial mode shaping. Analytical dependencies between the incident and focused spatial mode profiles parameters are provided.
Measuring small displacements of an optical point source with digital holography
Authors: Zhou Chaohui , Xin Jun , Li Yanan , Lu Xiao-Ming
Published: May 2023

The image of an optical point source is blurred due to light diffraction so that estimating small displacements of the point source with direct imaging demands elaborate processing on the observation data of a camera. Using quantum parameter estimation, we show that for the imaging systems with a real point spread function, any measurement basis constituted by a complete set of real-valued spatial-mode functions is optimal for estimating the displacement. For small displacements, we can concentrate the information about the value of displacement to the measurement of a few spatial modes, which can be selected in terms of the Fisher information distribution. We use digital holography with a phase-only spatial light modulator to implement two simple estimation strategies that are mainly based on the projection measurement of two spatial modes and the readout of a single pixel of a camera.
Zero-order free holographic optical tweezers
Authors: Yun Xue , Liang Yansheng , He Minru , Guo Linquan , Zhang Xinyu , Zhao Tianyu , Bianco Piero R. , Lei Ming
Published: May 2023

Holographic optical tweezers (HOTs) use spatial light modulators (SLM) to modulate light beams, thereby enabling the dynamic control of optical trap arrays with complex intensity and phase distributions. This has provided exciting new opportunities for cell sorting, microstructure machining, and studying single molecules. However, the pixelated structure of the SLM will inevitably bring up the unmodulated zero-order diffraction possessing an unacceptably large fraction of the incident light beam power. This is harmful to optical trapping because of the bright, highly localized nature of the errant beam. In this paper and to address this issue, we construct a cost-effective, zero-order free HOTs apparatus, thanks to a homemade asymmetric triangle reflector and a digital lens. As there is no zero-order diffraction, the instrument performs excellently in generating complex light fields and manipulating particles.
Strong interlayer coupling in p-Te/n-CdSe van der Waals heterojunction for self-powered photodetectors with fast speed and high responsivity
Authors: Hu Yanjie , Song Xiaohui , Jia Dongliang , Su Wanhan , Lv Xiaojing , Li Lin , Li Xueping , Yan Yong , Jiang Yurong , Xia Congxin
Published: May 2023

Self-driven photodetectors, which can detect optical signals without external voltage bias, are highly attractive in the field of low-power wearable electronics and internet of things. However, currently reported self-driven photodetectors based on van der Waals heterojunctions (vdWHs) are generally limited by low responsivity due to poor light absorption and insufficient photogain. Here, we report p-Te/n-CdSe vdWHs utilizing non-layered CdSe nanobelts as efficient light absorption layer and high mobility Te as ultrafast hole transporting layer. Benefiting from strong interlayer coupling, the Te/CdSe vdWHs exhibit stable and excellent self-powered characteristics, including ultrahigh responsivity of 0.94 A W-1, remarkable detectivity of 8.36 × 1012 Jones at optical power density of 1.18 mW cm-2 under illumination of 405 nm laser, fast response speed of 24 µs, large light on/off ratio exceeding 105, as well as broadband photoresponse (405-1064 nm), which surpass most of the reported vdWHs photodetectors. In addition, the devices display superior photovoltaic characteristics under 532 nm illumination, such as large Voc of 0.55 V, and ultrahigh Isc of 2.73 µA. These results demonstrate the construction of 2D/non-layered semiconductor vdWHs with strong interlayer coupling is a promising strategy for high-performance and low-power consumption devices.
Simple and compact high-power continuous-wave deep ultraviolet source at 261 nm based on diode-pumped intra-cavity frequency doubled Pr:LiYF4 green laser
Authors: Feng Kai , Wang Dong , Zhu Yizhen , Xu Bin , Chen Zhong , Baesso Mauro Luciano , Catunda Tomaz
Published: May 2023

We report the recent progress on diode-pumped high-power continuous-wave Pr:LiYF4 (YLF) green laser and deep ultraviolet (DUV) laser generation via intracavity frequency doubling. Using two InGaN blue diode lasers as pump source to form a double-end pumping geometry, in this work, we have demonstrated a green laser at 522 nm with a maximum output power of 3.42 W, which is believed to be the highest power ever achieved in all-solid-state Pr3+ lasers in this specific spectral region. Moreover, by intracavity frequency doubling of the achieved green laser, we have further obtained a DUV laser at about 261 nm with a maximum output power of 1.42 W, which is far higher than previous results. The watt-level 261-nm laser paves the way towards the realization of simple and compact DUV source for a variety of applications.
Noise analysis of the atomic superheterodyne receiver based on flat-top laser beams
Authors: Wang Zheng , Jing Mingyong , Zhang Peng , Yuan Shaoxin , Zhang Hao , Zhang Linjie , Xiao Liantuan , Jia Suotang
Published: May 2023

Since its theoretical sensitivity is limited by quantum noise, radio wave sensing based on Rydberg atoms has the potential to replace its traditional counterparts with higher sensitivity and has developed rapidly in recent years. However, as the most sensitive atomic radio wave sensor, the atomic superheterodyne receiver lacks a detailed noise analysis to pave its way to achieve theoretical sensitivity. In this work, we quantitatively study the noise power spectrum of the atomic receiver versus the number of atoms, where the number of atoms is precisely controlled by changing the diameters of flat-top excitation laser beams. The results show that under the experimental conditions that the diameters of excitation beams are less than or equal to 2 mm and the read-out frequency is larger than 70 kHz, the sensitivity of the atomic receiver is limited only by the quantum noise and, in the other conditions, limited by classical noise. However, the experimental quantum-projection-noise-limited sensitivity this atomic receiver reaches is far from the theoretical sensitivity. This is because all atoms involved in light-atom interaction will contribute to noise, but only a fraction of them participating in the radio wave transition can provide valuable signals. At the same time, the calculation of the theoretical sensitivity considers both the noise and signal are contributed by the same amount of atoms. This work is essential in making the sensitivity of the atomic receiver reach its ultimate limit and is significant in quantum precision measurement.
Impact of aerosols on the polarization patterns of full-sky background radiation
Authors: Li Shuai , Wang Rui , Dai Congming , Xu Wenqing , Zhan Jie
Published: May 2023

Regarding aerosol particle-laded turbid atmospheres, full-sky background radiation polarization patterns can be adversely affected, an important factor limiting their effective near-ground observation and acquisition. We established a multiple-scattering polarization computational model and measurement system and conducted the following three tasks. (a) We thoroughly analyzed the impact of aerosol scattering characteristics on polarization distributions, calculating the degree of polarization (DOP) and angle of polarization (AOP) patterns for a more comprehensive set of atmospheric aerosol compositions and aerosol optical depth (AOD) values than calculated in previous studies. (b) We assessed the uniqueness of the DOP and AOP patterns as a function of AOD. (c) By employing a new polarized radiation acquisition system for measurements, we demonstrated that our computational models are more representative of the DOP and AOP patterns under actual atmospheric conditions. We found that under a clear sky without clouds, the impact of the AOD on the DOP was detectable. With increasing AOD, the DOP decreased, and the decreasing trend became increasingly obvious. When the AOD was above 0.3, the maximum DOP did not exceed 0.5. The AOP pattern did not change notably and remained stable, except for the contraction point at the sun position under an AOD of 2.
Dual-branch fusion model for lensless imaging
Authors: Zhang Yinger , Wu Zhouyi , Xu Yunhui , Huangfu Jiangtao
Published: May 2023

A lensless camera is an imaging system that replaces the lens with a mask to reduce thickness, weight, and cost compared to a lensed camera. The improvement of image reconstruction is an important topic in lensless imaging. Model-based approach and pure data-driven deep neural network (DNN) are regarded as two mainstream reconstruction schemes. In this paper, the advantages and disadvantages of these two methods are investigated to propose a parallel dual-branch fusion model. The model-based method and the data-driven method serve as two independent input branches, and the fusion model is used to extract features from the two branches and merge them for better reconstruction. Two types of fusion model named Merger-Fusion-Model and Separate-Fusion-Model are designed for different scenarios, where Separate-Fusion-Model is able to adaptively allocate the weights of the two branches by the attention module. Additionally, we introduce a novel network architecture named UNet-FC into the data-driven branch, which enhances reconstruction by making full use of the multiplexing property of lensless optics. The superiority of the dual-branch fusion model is verified by drawing comparison with other state-of-the-art methods on public dataset (+2.95dB peak signal-to-noise (PSNR), +0.036 structural similarity index (SSIM), −0.0172 Learned Perceptual Image Patch Similarity (LPIPS)). Finally, a lensless camera prototype is constructed to further validate the effectiveness of our method in a real lensless imaging system.
Dynamic analysis of PAM-4 IM/DD OAM-based MGDM transmission enabled by mode-group filter approach
Authors: Zhang Jianbo , Wu Xiong , Lau Alan Pak Tao , Li Zhaohui , Lu Chao
Published: May 2023

Mode-group-division multiplexing (MGDM)-based intensity modulation direct detection (IM/DD) transmission is an attractive approach to increase the capacity for short-reach optical communication. In this Letter, a simple but versatile scheme of mode group (MG) filtering for MGDM IM/DD transmission is proposed. The scheme is applicable to any mode basis in the fiber, and it satisfies the needs of low complexity, low power consumption, and high system performance. By employing the proposed MG filter scheme, a total raw bit rate of a 152-Gb/s multiple-input-multiple-output (MIMO)-free IM/DD co-channel simultaneous transmit and receive system based on two orbital angular momentum (OAM) MGs, each carrying a 38-GBaud four-level pulse amplitude modulation (PAM-4) signal, is experimentally demonstrated over a 5-km few-mode fiber (FMF). The bit error ratios (BERs) of the two MGs are below the 7% hard-decision forward error correction (HD-FEC) BER threshold at 3.8×10-3, using simple feedforward equalization (FFE). Furthermore, the dependability and robustness of such MGDM links are of great significance. Thus, the dynamic evaluation of BER and signal-to-noise ratio (SNR) for each MG is tested over 210 minutes under different conditions. In the dynamic cases, all the BER results using the proposed scheme can be below 1×10-3, which further confirms the stability and feasibility of our proposed MGDM transmission scheme.
Highly polarized light emission from hybrid of quantum dots and plasmons in the intermediate coupling regime
Authors: Lan Xinhui , Shi Xiuqi , Zhang Lan , Guo Qianqian , Zou Zhen , Zhu Guangpeng , Li Xiang , Du Wei , Wang Tao
Published: May 2023

Colloidal semiconductor quantum dots (QDs), with a size tunable bandgap and remarkably high quantum efficiency, have been recognized as ideal light sources in quantum information and light emitting devices. For light sources, besides the emission intensity and spectral profile, the degree of polarization (DoP) is an essential parameter. Here, by embedding a monolayer of QDs inside the nanogap between a bottom Au mirror and a top Ag nanowire, we have demonstrated highly polarized light emission from the QDs with an average DoP of 0.89. In addition to the anisotropic photoluminescence (PL) intensity, the PL spectra are distinct at different polarizations, with an asymmetric spectral shape or even two-peak features. Such an anisotropic emission behavior arises from the coupling between the QDs and the largely confined and polarization-dependent gap-plasmons in the Au/QD/Ag nanocavities in the intermediate coupling regime. Our results demonstrate the possibility of achieving highly polarized light sources by coupling spherical QDs to single anisotropic plasmonic nanocavities, to provide new opportunities in the future design of polarized QD-based display devices.
Asymmetric phase modulation of light with parity-symmetry broken metasurfaces
Authors: Genevet Patrice , Mikheeva Elena , Colom Remi , Achouri Karim , Overvig Adam , Binkowski Felix , Duboz Jean-Yves , Cueff Sebastien , Fan Shanhui , Burger Sven , Alu Andrea
Published: May 2023

Optical components interact with light through radiative channels, and as such they experience
intrinsic losses, giving rise to complex-valued eigenfrequencies and singularities. Spatial inversion symmetry breaking -implemented herein by controlling the coupling efficiency between input and output radiative channels of metasurfaces- lifts the directional degeneracy of reflection zeros, and introduces a complex singularity with a positive imaginary part for full 2π-phase modulation of light. Our work establishes a general framework to predict and study the response of resonant systems in photonics and metaoptics.
Photonic integrated spiking neuron chip based on a self-pulsating DFB laser with a saturable absorber
Authors: Shi Yuechun , Xiang Shuiying , Guo Xingxing , Zhang Yahui , Wang Hongji , Zheng Dianzhuang , Zhang Yuna , Han Yanan , Zhao Yong , Zhu Xiaojun , Chen Xiangfei , Li Xun , Hao Yue
Published: May 2023

We proposed and experimentally demonstrated a simple and novel photonic spiking neuron based on a distributed feedback (DFB) laser chip with an intracavity saturable absorber (SA). The DFB laser with an intracavity SA (DFB-SA) contains a gain region and an SA region. The gain region is designed and fabricated by the asymmetric equivalent π-phase shift based on the reconstruction-equivalent-chirp technique. Under properly injected current in the gain region and reversely biased voltage in the SA region, periodic self-pulsation was experimentally observed due to the Q-switching effect. The self-pulsation frequency increases with the increase of the bias current and is within the range of several gigahertz. When the bias current is below the self-pulsation threshold, neuronlike spiking responses appear when external optical stimulus pulses are injected. Experimental results show that the spike threshold, temporal integration, and refractory period can all be observed in the fabricated DFB-SA chip. To numerically verify the experimental findings, a time-dependent coupled-wave equation model was developed, which described the physics processes inside the gain and SA regions. The numerical results agree well with the experimental measurements. We further experimentally demonstrated that the weighted sum output can readily be encoded into the self-pulsation frequency of the DFB-SA neuron. We also benchmarked the handwritten digit classification task with a simple single-layer fully connected neural network. By using the experimentally measured dependence of the self-pulsation frequency on the bias current in the gain region as an activation function, we can achieve a recognition accuracy of 92.2%, which bridges the gap between the continuous valued artificial neural networks and spike-based neuromorphic networks. To the best of our knowledge, this is the first experimental demonstration of a photonic integrated spiking neuron based on a DFB-SA, which shows great potential to realizing large-scale multiwavelength photonic spiking neural network chips.
Differential in-hospital mortality and intensive care treatment over time: Informing hospital pathways for modelling COVID-19 in South Africa
Authors: Jamieson Lise , Van Schalkwyk Cari , Nichols Brooke E. , Meyer-Rath Gesine , Silal Sheetal , Pulliam Juliet , Blumberg Lucille , Cohen Cheryl , Moultrie Harry , Jassat Waasila
Published: May 2023

There are limited published data within sub-Saharan Africa describing hospital pathways of COVID-19 patients hospitalized. These data are crucial for the parameterisation of epidemiological and cost models, and for planning purposes for the region. We evaluated COVID-19 hospital admissions from the South African national hospital surveillance system (DATCOV) during the first three COVID-19 waves between May 2020 and August 2021. We describe probabilities and admission into intensive care units (ICU), mechanical ventilation, death, and lengths of stay (LOS) in non-ICU and ICU care in public and private sectors. A log-binomial model was used to quantify mortality risk, ICU treatment and mechanical ventilation between time periods, adjusting for age, sex, comorbidity, health sector and province. There were 342,700 COVID-19-related hospital admissions during the study period. Risk of ICU admission was 16% lower during wave periods (adjusted risk ratio (aRR) 0.84 [0.82–0.86]) compared to between-wave periods. Mechanical ventilation was more likely during a wave overall (aRR 1.18 [1.13–1.23]), but patterns between waves were inconsistent, while mortality risk in non-ICU and ICU were 39% (aRR 1.39 [1.35–1.43]) and 31% (aRR 1.31 [1.27–1.36]) higher during a wave, compared to between-wave periods, respectively. If patients had had the same probability of death during waves vs between-wave periods, we estimated approximately 24% [19%-30%] of deaths (19,600 [15,200–24,000]) would not have occurred over the study period. LOS differed by age (older patients stayed longer), ward type (ICU stays were longer than non-ICU) and death/recovery outcome (time to death was shorter in non-ICU); however, LOS remained similar between time periods. Healthcare capacity constraints as inferred by wave period have a large impact on in-hospital mortality. It is crucial for modelling health systems strain and budgets to consider how input parameters related to hospitalisation change during and between waves, especially in settings with severely constrained resources.
Prioritizing interventions for cholera control in Kenya, 2015–2020
Authors: Boru Waqo , Xiao Shaoming , Amoth Patrick , Kareko David , Langat Daniel , Were Ian , Ali Mohammad , Sack David A. , Lee Elizabeth C. , Debes Amanda K.
Published: May 2023

Kenya has experienced cholera outbreaks since 1971, with the most recent wave beginning in late 2014. Between 2015–2020, 32 of 47 counties reported 30,431 suspected cholera cases. The Global Task Force for Cholera Control (GTFCC) developed a Global Roadmap for Ending Cholera by 2030, which emphasizes the need to target multi-sectoral interventions in priority cholera burden hotspots. This study utilizes the GTFCC’s hotspot method to identify hotspots in Kenya at the county and sub-county administrative levels from 2015 through 2020. 32 of 47 (68.1%) counties reported cholera cases during this time while only 149 of 301 (49.5%) sub-counties reported cholera cases. The analysis identifies hotspots based on the mean annual incidence (MAI) over the past five-year period and cholera’s persistence in the area. Applying a MAI threshold of 90th percentile and the median persistence at both the county and sub-county levels, we identified 13 high risk sub-counties from 8 counties, including the 3 high risk counties of Garissa, Tana River and Wajir. This demonstrates that several sub-counties are high level hotspots while their counties are not. In addition, when cases reported by county versus sub-county hotspot risk are compared, 1.4 million people overlapped in the areas identified as both high-risk county and high-risk sub-county. However, assuming that finer scale data is more accurate, 1.6 million high risk sub-county people would have been misclassified as medium risk with a county-level analysis. Furthermore, an additional 1.6 million people would have been classified as living in high-risk in a county-level analysis when at the sub-county level, they were medium, low or no-risk sub-counties. This results in 3.2 million people being misclassified when county level analysis is utilized rather than a more-focused sub-county level analysis. This analysis highlights the need for more localized risk analyses to target cholera intervention and prevention efforts towards the populations most vulnerable.
Prevalence, intensity and associated risk factors of soil-transmitted helminth infections among individuals living in Bata district, Equatorial Guinea
Authors: Ribado Meñe Gertrudis , Dejon Agobé Jean Claude , Momo Besahà Juan Carlos , Abaga Ondo Ndoho Florentino , Abdulla Salim , Adegnika Ayôla Akim
Published: May 2023

Background

Soil transmitted Helminths (STH) infections remain a public health concern worldwide, particularly in tropical and subtropical areas where these diseases are highly endemic. Knowing the prevalence and risk factors of the disease is crucial for efficient STH control strategies in endemic areas. The scarcity of epidemiological data on STH for Equatorial Guinea has motivated the decision to perform the present study.

Methods

A cluster-based cross-sectional study was carried out in Bata district from November 2020 to January 2021. Stool samples were collected for the diagnostic of STH infections using Kato-Katz technique. Descriptive statistics was performed for determination of STH prevalence and intensity, while logistic regression models were used to assess the risk factors associated with STH infections.

Results

A total of 340 participants were included in the study with a mean age of 24 years (SD = 23.7) and 1.2 female-to-male sex-ratio. The overall prevalence of any STH was 60% (95%CI: 55–65). The most prevalent species were Ascaris lumbricoides (43%, 95%CI: 37–48) and Trichuris trichiura (40%, 95%CI: 35–46). Intensity of infection were mainly light to moderate. A trend of association was observed between age and any STH infection (overall p-value = 0.07), with a significant difference observed between children aged 5–14 years as compared to those aged 1–4 (aOR 2.12; 95%CI: 1.02–4.43, p-value = 0.04), while locality was significantly associated with STH infection (overall p-value<0.001) with a higher odds observed for peri-urban area as compared to urban area (aOR 4.57; 95%CI: 2.27–9.60, p-value<0.001).

Conclusion

Bata district is a high STH transmission area, where school-aged children and peri-urban areas are associated with a higher risk of any STH infection. This situation calls for a full implementation of the WHO recommendations for STH control; mass drug administration of anthelminthic twice a year to the whole population with great attention to school age children, and prioritizing peri-urban areas where safe water, improve sanitation, and hygiene education should be implemented to achieve a better control.
The oldest plans to scale of humanmade mega-structures
Authors: Crassard Rémy , Abu-Azizeh Wael , Barge Olivier , Brochier Jacques Élie , Preusser Frank , Seba Hamida , Kiouche Abd Errahmane , Régagnon Emmanuelle , Sánchez Priego Juan Antonio , Almalki Thamer , Tarawneh Mohammad
Published: May 2023

Data on how Stone Age communities conceived domestic and utilitarian structures are limited to a few examples of schematic and non-accurate representations of various-sized built spaces. Here, we report the exceptional discovery of the up-to-now oldest realistic plans that have been engraved on stones. These engravings from Jordan and Saudi Arabia depict ‘desert kites’, humanmade archaeological mega-traps that are dated to at least 9,000 years ago for the oldest. The extreme precision of these engravings is remarkable, representing gigantic neighboring Neolithic stone structures, the whole design of which is impossible to grasp without seeing it from the air or without being their architect (or user, or builder). They reveal a widely underestimated mental mastery of space perception, hitherto never observed at this level of accuracy in such an early context. These representations shed new light on the evolution of human discernment of space, communication, and communal activities in ancient times.
Multi-ancestry genome- and phenome-wide association studies of diverticular disease in electronic health records with natural language processing enriched phenotyping algorithm
Authors: Joo Yoonjung Yoonie , Pacheco Jennifer A. , Thompson William K. , Rasmussen-Torvik Laura J. , Rasmussen Luke V. , Lin Frederick T. J. , Andrade Mariza de , Borthwick Kenneth M. , Bottinger Erwin , Cagan Andrew , Carrell David S. , Denny Joshua C. , Ellis Stephen B. , Gottesman Omri , Linneman James G. , Pathak Jyotishman , Peissig Peggy L. , Shang Ning , Tromp Gerard , Veerappan Annapoorani , Smith Maureen E. , Chisholm Rex L. , Gawron Andrew J. , Hayes M. Geoffrey , Kho Abel N.
Published: May 2023

Objective

Diverticular disease (DD) is one of the most prevalent conditions encountered by gastroenterologists, affecting ~50% of Americans before the age of 60. Our aim was to identify genetic risk variants and clinical phenotypes associated with DD, leveraging multiple electronic health record (EHR) data sources of 91,166 multi-ancestry participants with a Natural Language Processing (NLP) technique.

Materials and methods

We developed a NLP-enriched phenotyping algorithm that incorporated colonoscopy or abdominal imaging reports to identify patients with diverticulosis and diverticulitis from multicenter EHRs. We performed genome-wide association studies (GWAS) of DD in European, African and multi-ancestry participants, followed by phenome-wide association studies (PheWAS) of the risk variants to identify their potential comorbid/pleiotropic effects in clinical phenotypes.

Results

Our developed algorithm showed a significant improvement in patient classification performance for DD analysis (algorithm PPVs ≥ 0.94), with up to a 3.5 fold increase in terms of the number of identified patients than the traditional method. Ancestry-stratified analyses of diverticulosis and diverticulitis of the identified subjects replicated the well-established associations between ARHGAP15 loci with DD, showing overall intensified GWAS signals in diverticulitis patients compared to diverticulosis patients. Our PheWAS analyses identified significant associations between the DD GWAS variants and circulatory system, genitourinary, and neoplastic EHR phenotypes.

Discussion

As the first multi-ancestry GWAS-PheWAS study, we showcased that heterogenous EHR data can be mapped through an integrative analytical pipeline and reveal significant genotype-phenotype associations with clinical interpretation.

Conclusion

A systematic framework to process unstructured EHR data with NLP could advance a deep and scalable phenotyping for better patient identification and facilitate etiological investigation of a disease with multilayered data.
Digital tools for delivery of dementia education for caregivers of persons with dementia: A systematic review and meta-analysis of impact on caregiver distress and depressive symptoms
Authors: Scerbe Andrea , O’Connell Megan E. , Astell Arlene , Morgan Debra , Kosteniuk Julie , Panyavin Ivan , DesRoches Andrea , Webster Claire
Published: May 2023

Continuing education for dementia has been shown to be beneficial by improving informal caregiver knowledge, dementia care, management, and caregiver physical and mental health. Technology-based dementia education has been noted to have equivalent effects as in-person education, but with the added benefit of asynchronous and/or remote delivery, which increases accessibility. Using Cochrane review methodology, this study systematically reviewed the literature on technology-based dementia education and its impacts on caregivers. Technology-based delivery included dementia education delivered via the Internet, telephone, telehealth, videophone, computer, or digital video device (DVD). In the review, twenty-eight studies were identified with fourteen included in a meta-analysis, and these data revealed a significant small effect of technologically based dementia education on reducing caregiver depression, and a medium effect on reducing caregiver distress in response to caregivers’ observations of behavioral problems displayed by persons with dementia. No evidence was found for a significant effect of the educational intervention on caregiver burden or self-efficacy, which are known to be gendered aspects of caregiving. None of the studies included in the meta-analysis reported separate outcomes for male and female care providers, which has implications for gendered caregiving norms and aspects of care.

Registration number: PROSPERO 2018 CRD42018092599.
Skin microbiome alterations in upper extremity secondary lymphedema
Authors: Campbell Adana-Christine , Fei Teng , Baik Jung Eun , Park Hyeung Ju , Shin Jinyeon , Kuonqui Kevin , Brown Stav , Sarker Ananta , Kataru Raghu P. , Mehrara Babak J.
Published: May 2023

Lymphedema is a chronic condition that commonly occur from lymphatic injury following surgical resection of solid malignancies. While many studies have centered on the molecular and immune pathways that perpetuate lymphatic dysfunction, the role of the skin microbiome in lymphedema development remains unclear. In this study, skin swabs collected from normal and lymphedema forearms of 30 patients with unilateral upper extremity lymphedema were analyzed by 16S ribosomal RNA sequencing. Statistical models for microbiome data were utilized to correlate clinical variables with microbial profiles. Overall, 872 bacterial taxa were identified. There were no significant differences in microbial alpha diversity of the colonizing bacteria between normal and lymphedema skin samples (p = 0.25). Notably, for patients without a history of infection, a one-fold change in relative limb volume was significantly associated with a 0.58-unit increase in Bray-Curtis microbial distance between paired limbs (95%CI = 0.11,1.05, p = 0.02). Additionally, several genera, including Propionibacterium and Streptococcus, demonstrated high variability between paired samples. In summary, we demonstrate high compositional heterogeneity in the skin microbiome in upper extremity secondary lymphedema, supporting future studies into the role of host-microbe interactions on lymphedema pathophysiology.
Selecting police super-recognisers
Authors: Dunn James D. , Towler Alice , Kemp Richard I. , White David
Published: May 2023

People vary in their ability to recognise faces. These individual differences are consistent over time, heritable and associated with brain anatomy. This implies that face identity processing can be improved in applied settings by selecting high performers–‘super-recognisers’ (SRs)–but these selection processes are rarely available for scientific scrutiny. Here we report an ‘end-to-end’ selection process used to establish an SR ‘unit’ in a large police force. Australian police officers (n = 1600) completed 3 standardised face identification tests and we recruited 38 SRs from this cohort to complete 10 follow-up tests. As a group, SRs were 20% better than controls in lab-based tests of face memory and matching, and equalled or surpassed accuracy of forensic specialists that currently perform face identification tasks for police. Individually, SR accuracy was variable but this problem was mitigated by adopting strict selection criteria. SRs’ superior abilities transferred only partially to body identity decisions where the face was not visible, and they were no better than controls at deciding which visual scene that faces had initially been encountered in. Notwithstanding these important qualifications, we conclude that super-recognisers are an effective solution to improving face identity processing in applied settings.
Isolation and identification of hyaluronan-degrading bacteria from Japanese fecal microbiota
Authors: Akazawa Hazuki , Fukuda Itsuko , Kaneda Haruna , Yoda Shoichi , Kimura Mamoru , Nomoto Ryohei , Ueda Shuji , Shirai Yasuhito , Osawa Ro
Published: May 2023

Hyaluronan (HA) is a high-molecular-weight glycosaminoglycan and widely distributed in all connective tissues and organs with diverse biological functions. HA has been increasingly used as dietary supplements targeted to joint and skin health for humans. We here first report isolation of bacteria from human feces that are capable of degrading HA to lower molecular weight HA oligosaccharides (oligo-HAs). The bacteria were successfully isolated via a selective enrichment method, in which the serially diluted feces of healthy Japanese donors were individually incubated in an enrichment medium containing HA, followed by the isolation of candidate strains from streaked HA-containing agar plates and selection of HA-degrading strains by measuring HA using an ELISA. Subsequent genomic and biochemical assays identified the strains asBacteroides finegoldii,B.caccae,B.thetaiotaomicron, andFusobacterium mortiferum. Furthermore, our HPLC analysis revealed that the strains degraded HA to oligo-HAs of various lengths. Subsequent quantitative PCR assay targeting the HA degrading bacteria showed that their distribution in the Japanese donors varied. The evidence suggests that dietary HA is degraded by the human gut microbiota with individual variation to oligo-HAs components, which are more absorbable than HA, thereby exerting its beneficial effects.