bluuebunny/crossref_metadata_2025 huggingface dataset:
Facilitating choice when engaging young people with disabilities: reflections from co-researcher training
Authors: Nicholson Emma , Mimmo Laurel , Christophers Lauren , Costa Sa Maria Elena , MacKeogh Trish
Published: August 2024

Background

A collaborative approach is critical in inclusive research and should incorporate taking time to build relationships with co-researchers based on trust and shared understanding. Involvement can often be seen as tokenistic and in order to avoid this, it is important to provide opportunities for people to exercise choice throughout the research process.

Main body

The current paper outlines learnings from a co-researcher training process for young people with disabilities to identify the ways in which meaningful choice can be facilitated with this group. While conducting training of co-researchers in topics such as research methods, we were continuously led by the group with regards to the directions that the sessions took and promoted problem solving with the group to accommodate the unique needs of all members. The overall aim of a wider project was to develop research capacity in a group of young people with disabilities through co-researcher training and this paper will report on learnings from this work with regards to how we sought to provide opportunities for the co-researchers to exercise choice within research projects. Feedback from the group of young people highlighted the variety of needs and expectations that must be accommodated in such a process and therefore, allowing them to dictate the extent and manner of their engagement is key. Young people with disabilities are a heterogeneous group and therefore, some methodologies and ways of working required adaptation in order to facilitate meaningful choice and engagement for all.

Conclusion

Providing meaningful opportunities for demonstrating their choices, in relation to elements of research projects, is a critical component of facilitating a rights-based approach when conducting co-research and requires researchers to cede some level of control over the research process to co-researchers. This can be difficult to achieve in practice and researchers must continuously reflect on their own practice and be willing to change and adapt throughout the process.
Actinomyces funkei bacteraemia and infected pulmonary cavities in an intravenous drug user: a case report
Authors: Perinpanathan Tanaraj , Beckett Katherine , Smith Chris
Published: August 2024

Background

Actinomyces spp. are most commonly found in human commensal flora; however, they have also been shown to cause suppurative infections. We present a case of a rare Actinomyces funkei bacteraemia from an infected deep vein thrombosis in a patient who went on to develop pulmonary cavities secondary to septic emboli. Infected thrombi and septic emboli have been associated with other Actinomyces spp. in the literature, often posing a diagnostic challenge and, in some cases, causing drastic clinical deterioration in patients. The literature regarding Actinomyces funkei is scarce and to our knowledge there are no reports of a relationship between this Actinomyces subspecies and infected thrombi or septic emboli.

Case presentation

The patient was a 39-year-old known intravenous drug user who presented with a groin injecting site sinus and systemic symptoms. The bacteria was first observed by gram staining of a blood culture sample after 48 h of incubation and the species was identified using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) as Actinomyces funkei. Sputum cytology/histology with cell block revealed a branching gram-positive species suspicious of slow growing bacteria or fungus. CT imaging of his lower limb and chest revealed an extensive DVT with inflammatory changes and pulmonary cavities respectively. The patient was treated with Ceftriaxone before being discharged with a 6-month course of Linezolid. He made a good recovery with reduction in size of the cavitating lung lesions on follow-up imaging.

Conclusions

This case report presents a difficult-to-diagnose bacterial infection in an intravenous drug user, complicated by bacteraemia and secondary septic emboli. Relatively little is known about Actinomyces funkei, and therefore this report aims to increase clinician awareness of diagnosis, management, and complications.
Untrammeling the wilderness: restoring natural conditions through the return of human-ignited fire
Authors: Boerigter Clare E. , Parks Sean A. , Long Jonathan W. , Coop Jonathan D. , Armstrong Melanie , Hankins Don L.
Published: August 2024

Historical and contemporary policies and practices, including the suppression of lightning-ignited fires and the removal of intentional fires ignited by Indigenous peoples, have resulted in over a century of fire exclusion across many of the USA’s landscapes. Within many designated wilderness areas, this intentional exclusion of fire has clearly altered ecological processes and thus constitutes a fundamental and ubiquitous act of trammeling. Through a framework that recognizes four orders of trammeling, we demonstrate the substantial, long-term, and negative effects of fire exclusion on the natural conditions of fire-adapted wilderness ecosystems. In order to untrammel more than a century of fire exclusion, the implementation of active programs of intentional burning may be necessary across some wilderness landscapes. We also suggest greater recognition and accommodation of Indigenous cultural burning, a practice which Tribes used to shape and maintain many fire-adapted landscapes for thousands of years before Euro-American colonization, including landscapes today designated as wilderness. Human-ignited fire may be critical to restoring the natural character of fire-adapted wilderness landscapes and can also support ecocultural restoration efforts sought by Indigenous peoples.
Adaptive wildfire spread prediction for complex terrain: modeling the effectiveness of sprinkler systems
Authors: Kim Jaekyoung , Ahn Junghyeon , Kang Junsuk
Published: August 2024

Background

Because the threat of wildfires to global ecosystems and society continues to rise, this study provides an experimental simulation framework that assesses the spread and reduction of wildfires to evaluate the effectiveness of adaptation methods in reducing their impact. The process entails selecting a vulnerable wildfire area and adaptation method, then generating the computational fluid dynamics (CFD) model. Monitoring data are then used to configure the model, set boundary conditions, and simulate the fire. The effectiveness of the adaptation method in minimizing damage in the area of interest is evaluated by comparing simulations with and without the chosen adaptation method. Our focus area was a natural recreational forest in Wonju, Gangwon-do, Korea, and our adaptation method was a water sprinkler system.

Results

Our framework provides aims to provide an experimental means of assessing the wildfire spread path and spread area based on exogenous variables of wind speed, wind direction, relative humidity, and more. The sprinkler adaptation had a reduction effect of 20% in the wildfire spread rate for the 10-h period, which refers to the time limit of the simulation after ignition. We revealed that at higher wind speeds, the fire primarily follows the wind direction; whereas at lower wind speeds, the fire is more influenced by the topography. Additionally, 60 min after ignition, the adaptation methods can suppress wildfire spread by > 70%. Notably, sprinklers reduce smoke concentrations by up to 50% (ppm) over the affected area.

Conclusions

This study demonstrates the potential effectiveness of a comprehensive CFD model in mitigating wildfire spread using sprinkler systems as an experimental analysis. Key results include a 20% reduction in wildfire within 10 h of ignition, significant influence of wind speed on spread patterns, and a reduction of smoke concentrations, improving air quality. These findings highlight the potential of CFD-based frameworks to enhance wildfire response strategies. However, it is important to note that this study’s limitations include the lack of experimental or measured fire behavior data, which should be considered when interpreting the effectiveness of the CFD model.
Validation of angiography-derived Murray law-based quantitative flow reserve (μQFR) against pressure-derived instantaneous wave-free ratio for assessing coronary lesions, a single-center study in Egypt
Authors: Samaan Amir Anwar , Mostafa Amir , Wahba Sherif Lotfy , Kerlos Matteo , Elamragy Ahmed Adel , Shelbaya Khaled , Elsobky Yasmin , Hassan Mohamed
Published: August 2024

Background

Instantaneous wave-free ratio (iwFR) is a well-validated method for functional evaluation of intermediate coronary lesions. A recently developed Murray law-based QFR (µQFR) allows wire-free FFR estimation using a high-quality single angiographic projection. We aim to determine the diagnostic accuracy of µQFR as compared to wire-based iwFR for physiological assessment of coronary lesions in a sample of Egyptian patients.

Results

Over a one-year period, patients who previously underwent iwFR assessment of an intermediate coronary stenosis (40–90%) were retrospectively included. μQFR analysis was then performed offline using a dedicated artificial intelligence (AI)-aided computation software. All the measurements were performed blinded to iwFR results, and the agreement between iwFR and μQFR values was tested. Forty-nine patients (mean age 57.9 ± 9 years, 72.9% males) were included. Mean value of iwFR and μQFR was 0.90 ± 0.075 and 0.79 ± 0.129, respectively. There was a significant moderate positive linear correlation between μQFR and iwFR (r = 0.47, p = 0.001; 95% CI 0.22–0.68) with moderate-to-substantial agreement between the two methods (Kappa 0.6). In assessing the diagnostic accuracy of μQFR, the receiver operating characteristic (ROC) curve yielded an area under the curve (AUC) of 0.84 (95% CI 0.717–0.962) for predicting functionally significant lesions defined as iwFR < 0.89. The sensitivity and specificity of μQFR < 0.8 for detecting physiological significance of coronary lesions were 89% and 74% with positive and negative predictive values of 70 and 91%, respectively.

Conclusion

µQFR has good diagnostic accuracy for predicting functionally significant coronary lesions with moderate correlation and agreement with the gold standard iwFR. Angiography-derived µQFR could be a promising tool for improving the utilization of physiology-guided revascularization.
Evacuation
Authors: Adey Peter
Published: August 2024

In Evacuation, Peter Adey examines the politics, aesthetics, and practice of moving people and animals from harm during emergencies. He outlines how the governance and design of evacuation are recursive, operating on myriad political, symbolic, and affective levels in ways that reflect and reinforce social hierarchies. Drawing on a wide range of case studies, from the retrieval of wounded soldiers from the battlefield during World War I and escaping the World Trade Center on 9/11 to the human and animal evacuations in response to the 2009 Australian bushfires and the 2010 Haiti earthquake, Adey demonstrates that evacuation is not an equal process. Some people may choose not to move while others are forced; some may even be brought into harm through evacuation. Often the poorest, racialized, and most marginalized communities hold the least power in such moments. At the same time, these communities can generate compassionate, creative, and democratic forms of care that offer alternative responses to crises. Ultimately, Adey contends, understanding the practice of evacuation illuminates its importance to power relations and everyday governance.
The Use of Augmented Reality as an Educational Tool in Minimally Invasive Transforaminal Lumbar Interbody Fusion
Authors: Schmidt Franziska A. , Hussain Ibrahim , Boadi Blake , Sommer Fabian J. , Thomé Claudius , Härtl Roger
Published: August 2024

BACKGROUND AND OBJECTIVES:

One of the major challenges in training neurosurgical and orthopedic residents the technique for minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is the lack of visualization of surgical landmarks (pedicle, pars, lamina). This is due to the limited access to the bony spine through a tubular retractor, in addition to a smaller working corridor or patient-specific factors such as bony overgrowth, disk space collapse, and listhesis. These factors increase the possibility for surgical error and prolonged surgery time. With augmented reality (AR), relevant surgical anatomy can be projected directly into the user's field of view through the microscope. The purpose of this study was to assess the utility, accuracy, efficiency, and precision of AR-guided MIS-TLIF and to determine its impact in spine surgery training.

METHODS:

At 2 centers, 12 neurosurgical residents performed a one-level MIS-TLIF on a high-fidelity lumbar spine simulation model with and without AR projection into the microscope. For the MIS-TLIF procedures with AR, surgical landmarks were highlighted in different colors on preoperative image data. These landmarks were visualized in the spinal navigation application on the navigation monitor and in the microscope to confirm the relevant anatomy. Postprocedural surveys (National Aeronautics and Space Administration Task Load Index) were given to the residents.

RESULTS:

Twelve residents were included in this trial. AR-guided procedures had a consistent impact on resident anatomical orientation and workload experience. Procedures performed without AR had a significantly higher mental demand (
P = .003) than with AR. Residents reported to a significantly higher rate that it was harder work for them to accomplish their level of performance without AR (
P = .019).

CONCLUSION:

AR can bring a meaningful value in MIS teaching and training to confirm relevant anatomy in situations where the surgeon will have less direct visual access. AR used in surgical simulation can also speed the learning curve.
Code and Data Repository for frvcpy: An Open-Source Solver for the Fixed Route Vehicle Charging Problem
Authors: Kullman Nicholas , Froger Aurelien , Mendoza Jorge , Goodson Justin
Published: August 2024

The software and data in this repository are a snapshot of the software and data that were used in the research reported on in the paper frvcpy: An Open-Source Solver for the Fixed Route Vehicle Charging Problem by N. Kullman, A. Froger, JE Mendoza, and J. Goodson. The snapshot is based on this SHA in the development repository.
Code and Data Repository for alfonso: Matlab Package for Nonsymmetric Conic Optimization
Authors: Papp Dávid , Yıldız Sercan
Published: August 2024

The software in this repository is a snapshot (last revised on 2020/07/20) of the software that was used in the research reported in the paper alfonso: Matlab package for nonsymmetric conic optimization by Dávid Papp and Sercan Yıldız.
Code and Data Repository for AILS-II: An Adaptive Iterated Local Search Heuristic for the Large-Scale Capacitated Vehicle Routing Problem
Authors: Máximo Vinícius R. , Cordeau Jean-François , Nascimento Mariá C. V.
Published: August 2024

AILS-II is an Adaptive Iterated Local Search (AILS) meta-heuristic that embeds adaptive strategies to tune diversity control parameters. These parameters are the perturbation degree and the acceptance criterion. They are key parameters to ensure that the method escapes from local optima and keeps an adequate level of exploitation and exploration of the method. Its implementation is in JAVA language.
Advising Entrepreneurs: Optimal Recommendation of Alternatives
Authors: Wang Zeya , Rahmani Morvarid , Ramachandran Karthik
Published: August 2024

Problem definition: Facing emergent business challenges, entrepreneurs often seek guidance from experienced advisors. When multiple alternatives could potentially solve the entrepreneur’s problem, advisors can lead the entrepreneur’s exploration by choosing which alternative(s) to suggest and in what sequence. Methodology/results: We develop a dynamic game-theoretic model that captures the sequential interaction between an advisor and an entrepreneur. The advisor chooses how to recommend alternative solutions, and the entrepreneur chooses which solution to try. The trial’s success depends on the viability of a solution and the entrepreneur’s execution capability. When a trial of a recommended solution fails, the belief about the viability of the solution is updated. Managerial implications: Our analysis reveals that the advisor should strategically recommend alternatives based on the entrepreneur’s execution capability, trial costs, and correlation between alternatives (among other factors). When the trial of the first alternative fails, the advisor should readily offer a new alternative if the entrepreneur’s capability is either very high or very low. Otherwise, the advisor should encourage the entrepreneur to try the same solution multiple times. In order to motivate and sustain the entrepreneur’s exploration over time and across solutions, the advisor may find it optimal to recommend inferior solutions before superior ones (e.g., when trial costs are different or the entrepreneur can improve her capability with experience) or recommend multiple solutions simultaneously (e.g., when there is correlation between alternatives).

Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0361 .
Error Propagation in Asymptotic Analysis of the Data-Driven (s, S) Inventory Policy
Authors: Zhang Xun , Ye Zhi-Sheng , Haskell William B.
Published: August 2024

Estimating Optimal Inventory Policies: Moving Beyond SAA and Empirical Process Theory

In “Error Propagation in Asymptotic Analysis of the Data-Driven (s,S) Inventory Policy,” Zhang, Ye, and Haskell dive into the class multiperiod stochastic inventory control in a data-driven setting. They investigate the statistical properties of the data-driven $(s, S)$-policy obtained by recursively computing the empirical cost-to-go functions. In this setting, the empirical cost-to-go functions for the estimated parameters are not i.i.d. sums because of the error propagation. They establish a novel asymptotic representation for multi-sample $U$-processes in terms of i.i.d. sums. This representation enables them to apply empirical process theory to derive the influence functions of the estimated parameters and to establish joint asymptotic normality. Based on these results, they also propose an entirely data-driven estimator of the optimal expected cost and derive its asymptotic distribution. They demonstrate some useful applications of their asymptotic results, including sample size determination and interval estimation.
Cardiac autonomic regulation during submaximal exercise in women with fibromyalgia
Authors: Schamne Julio Cezar , Santos Pamela Souza , Cavalcante Victor Henrique Vieira , Gonçalves Felippi , Cristina-Souza Gislaine , Marinho Alisson Henrique , Senoski Saulo , Bertuzzi Romulo , Okuno Nilo Massaru , Lima-Silva Adriano Eduardo
Published: August 2024

Fibromyalgia (FM) patients present impaired cardiac autonomic regula-tion during maximal exercise; however, it is unknown whether these al-terations also manifest during submaximal exercise. The aim of this study was to compare the on-transient heart rate (HR) response and HR variability during a constant-load submaximal cycling exercise between FM and control (CON) women. Ten women with FM (age: 45.2±9.3 years) and 10 age-matched CON women (age: 48.4±6.1 years) performed a 15-min cycling exercise, with the work rate fixed at 50% of the individual peak power output attained in a maximal graded exercise test. The time intervals between consecutive heartbeats were recorded regularly during the exercise for subsequent analysis of on-transient HR response and HR variability indices. The on-transient HR time constant was simi-lar (p=0.83) between the FM (41.0±14.1 sec) and CON (42.2±10.4 sec). During the 5–10 and 10–15 min of exercise, HR variability indices indi-cating sympathetic and parasympathetic activities were similar (p>0.05) between FM and CON groups. In conclusion, women with FM present-ed a normal cardiac autonomic response to submaximal cycling exer-cise. These findings have clinical relevance, as submaximal exercises are commonly prescribed for FM patients.
Electro-optical intensity and phase modulations of a racetrack micro-resonator based on a LiNbO3-silicon hybrid waveguide covered by electro-optical polymers
Authors: Ma Tao , Wang Huan , Liu Heng
Published: August 2024

Rapid developments of 5G have led to ever-increasing demands for high-performance modulators. To improve modulation performances, an electro-optical (EO) modulator based on a racetrack micro-resonator (RMR) covered by EO polymers is demonstrated. The RMR-based EO modulator consists of LiNbO3-silicon hybrid waveguides (LSHWs) and an EO polymer coating. The finite element method (FEM) is used to obtain the transmission and modulation characteristics of the LSHWs-RMR. The simulation results show that the EO modulator based on the LSHWs-RMR has an EO wavelength tuning (λEO) of 32 pm/V and a phase shift per volt (φEO) of −0.0376rad/V for the quasi-TE mode. For the quasi-TM mode, there is a λEO of 40 pm/V and a φEO of −0.0350rad/V. The calculated Vπ⋅L for the quasi-TE and quasi-TM modes are 0.45V⋅cm and 0.40V⋅cm, respectively. The proposed EO modulator based on the LSHWs-RMR has potential application prospects in coherent optical fiber communication systems, comb generators for generating multiple optical frequencies in dense wavelength division multiplexing optical fiber systems, and electro-optical frequency shifters for laser beams.
Open-loop optimization method based on the GRU and dual-grating demodulation principle for a PZT based optical voltage sensor
Authors: Liu Cirui , He Yanxiao , Sun Weidong , Zhang Xinghong , He Xuefeng , Xiong Haoyu
Published: August 2024

Distributed online monitoring of grid voltage is crucial for ensuring power quality, providing a foundational data layer for effective grid management. Piezoelectric grating optical voltage sensing presents a cost-effective solution with high bandwidth and long-distance transmission capabilities. This paper introduces an open-loop optimization approach that leverages the gate recurrent unit (GRU) and dual-grating demodulation principles to enhance the real-time response accuracy and extend the measurement range of piezoelectric-based optical voltage sensors. Experiments conducted within a 2.8 kV sensing range analyze the voltage response and spectral characteristics. After applying corrections, the sensor achieves a linearity of 99.93%, with a maximum deviation of 2.07% and a maximum hysteresis of 3.33%. This method significantly enhances real-time response accuracy and optimizes the utilization of the sensor’s nonlinear measurement range, advancing the application of optical voltage sensors in power grids.
Effect of laser ablation of substrate on the morphology of the laser cladding layer
Authors: Chen Yongqian , Qiu Jinqian , Liu Jialin , Yang Aohui , Lin Zhibin , Chen Xin , Jia Xianshi , Li Kai , Guo Shirui , Cui Yinghao , Zheng Bo , Lai Yang , Wu Xiwang , Cui Lujun
Published: August 2024

How to accurately and effectively modulate the morphology of the laser cladding layer is very important in the field of laser surface strengthening. In this paper, the surface morphology and roughness of the cladding substrate are accurately controlled by the nanosecond laser ablation process, and its influence on the morphology of the cladding layer is analyzed. Before laser cladding, a nanosecond laser was used to perform ablation pretreatment on the surface of 45 steel substrate. The analysis results show that when the laser power exceeds the ablation threshold, the substrate surface forms a microsphere structure caused by the melting–solidification process. At the same time, a linear relation between the substrate surface roughness and the laser power was obtained. Subsequently, a laser cladding experiment was performed on the roughened substrate surface, and the morphology of the cladding layer was analyzed. The results show that after the substrate is ablated by a nanosecond laser, the cladding angle, dilution rate, and cladding depth of the cladding layer decrease with the increase of the substrate surface roughness, and the clad width and clad height increase with the increase of the surface roughness. The results show that the surface roughness of the substrate can be accurately controlled by the laser ablation method, which can help to optimize the macroscopic morphology of the laser cladding layer and obtain a cladding coating with better performance.
High-quality Mid-infrared Chalcogenide Ring Resonator
Authors: Lu Bright , Xu Bo , Krueper Greg , Zohrabi Mo , Gopinath Juliet T. , Park Wounjhang
Published: August 2024

We report Ge23Sb7S70 chalcogenide ring resonators with up to 8 × 104 quality factors operating around 3.6 µm wavelength fabricated through e-beam lithography. Their rib waveguide geometry can be engineered to support close-to-zero dispersion modes needed for mid-infrared microcomb generation.
20 µm resolution multipixel ghost imaging with high-energy x-rays
Authors: Sefi O. , Ben Yehuda A. , Klein Y. , Sobol Z. , Bloch S. , Schwartz H. , Cohen E. , Shwartz S.
Published: August 2024

Hard x-ray imaging is indispensable across diverse fields owing to its high penetrability. However, the resolution of traditional x-ray imaging modalities, such as computed tomography (CT) systems, is constrained by factors including beam properties, the limitations of optical components, and detection resolution. As a result, the typical resolution in commercial imaging systems that provide full-field imaging is limited to a few hundred microns, and scanning CT systems are too slow for many applications. This study advances high-photon-energy imaging by extending the concept of computational ghost imaging to multipixel ghost imaging with x-rays. We demonstrate a remarkable resolution of approximately 20 µm for an image spanning 0.9 by 1 cm2, comprised of 400,000 pixels and involving only 1000 realizations. Furthermore, we present a high-resolution CT reconstruction using our method, revealing enhanced visibility and resolution. Our achievement is facilitated by an innovative x-ray lithography technique and the computed tiling of images captured by each detector pixel. Importantly, this method maintains reasonable timeframes and can be scaled up for larger images without sacrificing the short measurement time, thereby opening intriguing possibilities for noninvasive high-resolution imaging of small features that are invisible with the present modalities.
Competition between turbulence and thermal blooming of coherent vortex beam array propagating in non-Kolmogorov marine atmosphere
Authors: Yang Bowen , Yu Hong , Hu Hanyin , Zhong Zheqiang , Zhang Bin
Published: August 2024

The competition between turbulence and thermal blooming significantly affects the propagation characteristics of laser beams in the atmosphere. Here, taking the propagation of a vortex beam array in a non-Kolmogorov marine atmosphere as an example, we have quantitatively analyzed the competition between turbulence and thermal blooming. The atmospheric coherence length is adopted to evaluate the turbulence strength, while a modified thermal distortion parameter is developed to evaluate the thermal blooming strength of vortex beam arrays in non-Kolmogorov turbulence. Results indicate that, in strong turbulence, there is a significant variation in the beam characteristics at the target plane as the spectral power law index increases, whereas this relationship exhibits a smoother change in weak turbulence. More interestingly, our results suggest that for a fixed aperture of laser emission systems, increasing the initial power density may not always lead to a higher average power density at the target plane, and there exists an optimal value no matter what the intensity of the turbulence is, i.e., weak, moderate, and strong turbulence. We hope these results may provide useful guidance for laser communication, laser power transmission, etc.
Free-space optical communication link using a single Laguerre-Gaussian beam with tunable radial and azimuthal spatial indices generated by an integrated concentric circular antenna array
Authors: Song Hao , Zhou Huibin , Zou Kaiheng , Zhang Runzhou , Su Xinzhou , Pang Kai , Song Haoqian , Duan Yuxiang , Minoofar Amir , Bock Robert , Zach Shlomo , Tur Moshe , Willner Alan E.
Published: August 2024

We experimentally demonstrate a 10-Gbit/s free-space communication link using a single Laguerre-Gaussian (LG) beam with tunable radial and azimuthal modal indices generated by a photonic integrated circuit comprising two concentric uniform circular antenna arrays (UCAs). To tune the azimuthal modal indices ℓ of the generated beam, the azimuthal phase gradient inside each UCA is tuned. To tune the radial mode p of the generated beam, the amplitude ratio and phase difference between the two concentric UCA are tuned. To implement the above functions, the integrated device is composed of (a) two concentric UCAs where the inner (outer) UCA has 4 (8) optical antennas, (b) one Mach-Zehnder interferometer to control the amplitude ratio between the two UCAs, (c) one phase shifter to control the phase distribution between the two UCAs, and (d) phase shifters to control the azimuthal phase gradient of the inner and outer UCA. In our experiment, (a) the two modal indices of the generated beam are independently tuned (ℓ ={0,+1},p={0,1}), (b) the measured mode purity of the generated beam ranges from 23% to 38% among different target LG modes, and (c) a 10-Gbit/s chip-to-free-space optical link carried by the generated tunable LG beam is demonstrated.
Performance analysis and experimental evaluation of modulating retroreflector and UAV based free space optical transmission systems
Authors: Chen Chao , Ji Jianhua , Zhao Hongwei , Song Yufeng
Published: August 2024

This paper introduces a novel unmanned aerial vehicle (UAV) based free space optical (FSO) communication system that integrates differential detection with a modulating retro-reflector (MRR) to enhance performance. We provide a comprehensive analysis of the system's performance, taking into account critical factors including atmospheric path loss, non-zero boresight pointing error, atmospheric turbulence, and angle of arrival (AoA) fluctuations induced by UAV orientation fluctuations. To facilitate this analysis, we have derived the probability density function (PDF) and cumulative distribution function (CDF) for the end-to-end signal-to-noise ratio (SNR) under these channel conditions. Our study presents new closed-form solutions for pivotal performance metrics: outage probability (OP), average bit error rate (ABER), and ergodic capacity (EC), which are corroborated through Monte Carlo simulations. Additionally, we perform asymptotic analyses to gain deeper insights into the behavior of OP, ABER, and EC. A pioneering experimental setup has been constructed to empirically validate the communication performance of our proposed system. The numerical findings underscore the presented system's feasibility and the significant impact of atmospheric turbulence and pointing errors on system performance. Moreover, our experimental results indicate that the proposed system outperforms current UAV-based MRR FSO systems under identical conditions.
Difference of two sinc Schell-model cross-spectral density matrices
Authors: Li Jiachang , Mei Zhangrong
Published: August 2024

We propose a convenient method for modeling what we believe to be novel classes of cross-spectral density (CSD), in which the difference between two CSD matrices belonging to the same class represents a supposed novel valid CSD matrix under sufficient conditions. Using such a method, we introduce what we think is a new class of CSD matrix relating to the difference of two sinc Schell-model CSD matrices, and derive the sufficient conditions for the non-negative definiteness of the resulting CSD matrix. The statistical characteristics of such electromagnetic stochastic beams propagating in free space were investigated using weighted superposition and numerical simulation methods. It is demonstrated that this new light fields with any admissible choice of source parameters possess very peculiar evolution characteristics. The results illustrate new opportunities for study new classes of electromagnetic stochastic beams.
Amplitude-boosting attack against practical discrete-modulated continuous-variable quantum key distribution
Authors: Wu Mingze , Bian Yiming , Li Junhui , Yu Song , Zhang Yichen
Published: August 2024

Discrete-modulated continuous-variable quantum key distribution offers significant practical deployment advantages due to its straightforward state preparation and high compatibility with coherent optical communication systems. However, security analysis and parameter estimation of discrete-modulated protocol are different with Gaussian-modulated protocols, which could cause different practical security problems. Herein, we investigate the amplitude-boosting attack against discrete-modulated continuous-variable quantum key distribution systems and assess its impact on system performance. Our findings reveal that this attack could cause overestimation of secret key rate perceived by Alice and Bob, thereby opening a security loophole, and the vulnerability could be severer than Gaussian modulation. Additionally, we summarize defensive countermeasures, marking a crucial step towards enhancing the practical security of discrete-modulated continuous-variable quantum key distribution.
Chaos-driven seven-core optical transmission scheme based on DNA full information chained analog-transcription
Authors: Chen Gengyin , Liu Bo , Ren Jianxin , Mao Yaya , Song Xiumin , Wu Xiangyu , Chen Shuaidong , Ullah Rahat , Qi Zhipeng , Wu Yongfeng , Sun Tingting , Li Ying , Zhao Lilong , Wang Feng
Published: August 2024

This paper proposes a chaos-driven seven-core optical transmission scheme based on DNA full information chained analog-transcription. Unlike traditional deoxyribonucleic acid (DNA) coded encryption schemes in the bit dimension, this scheme uses chaotic sequences to generate perturbed bit streams corresponding to the initial bit stream. These two sets of bit streams are encoded from a set of DNA double-stranded sequences, which are then intertwined into a single-stranded DNA containing all the information through the full-information class transcription algorithm proposed in this paper. Finally, the DNA decoding process is driven by a set of sequences derived from another chaotic model to transform the DNA sequence containing all information back into a bit sequence for subsequent transmission. Additional chaotic sequences interfere with the subcarriers, symbols, and constellation angles. Moreover, to maintain spectral efficiency, hiding the key in the frame header allows for the dynamic simultaneous transmission of signal and key. The transmission of encrypted 16 quadrature amplitude modulation-orthogonal chirp division multiplexing (16QAM-OCDM) signals is experimentally demonstrated at a net bit rate of 51.72 Gb/s over 2 km weakly coupled seven-core fiber. At the receiving end, the correct key decoder is able to accurately recover the data, while the bit error ratio (BER) at the illegal receiving end is 0.5. Finally, quantitative experiments validate the receiver-side decryption algorithm, showing that the proposed encryption scheme achieves a large key space of 10397. The key can be fully decoded when the optical power is above -20dBm. This scheme significantly enhances the security and flexibility of the communication system, making it a promising candidate for future optical communication physical layer encryption.
Design and experimental research of orbital angular momentum multiplexing holography based on optical diffraction neural network
Authors: Geng Shuai , Xu Ping , Sun Yiling , Yang Tuo , Huang Haixuan , Zhang Xulin , Wang Mengyu , Li Xiongchao , Xiao Yufei , Xu Haidong , Wu Yuanyang , Li Hongguang , Di Yutong
Published: August 2024

The orbital angular momentum (OAM) multiplexing holography has the advantages of large information capacity and high security, and has important application value in holographic storage, optical encryption, and optical computing. However, as the number of multiplexing channels increases, this technology suffers from deterioration in image quality, which limits its application scope. This article proposes an innovative design that introduces an optical diffractive neural network (ODNN) into OAM multiplexing holography, establishes a scientific image quality evaluation function, applies an end-to-end optimization method, and designs OAM multiplexing holograms in parallel, significantly improving the image quality of OAM holography. The design results show that compared to classical methods, the ODNN method proposed in this paper has improved diffraction efficiency and signal-to-noise ratio by 29% and 19%, respectively, and reduced mean square error and variance by 10% and 43%, respectively. Moreover, high-quality multi-channel OAM multiplexing holography has been achieved through experiments. The design method proposed in this article provides an efficient and practical way for future OAM multiplexing holographic technology to further enhance information capacity and improve security.
Ultralow thermal conductivity of 2D Dion–Jacobson (PDA)(FA)n − 1PbnI3n + 1 perovskite films
Authors: Yang Wei , Chen Xiangyu , Yuan Mingqian , Geng Zhiming , Zhao Hongyuan , Wang Huan , Zeng Zhongle , Chai Nianyao , Yue Yunfan , Zhao Fengyi , Li Sheng , Lu Minghui , Chen Yanfeng , Yan Xuejun , Wang Xuewen
Published: August 2024

Two-dimensional (2D) perovskites exhibit enhanced thermal stability compared to three-dimensional perovskites, especially the emerging 2D Dion–Jacobson (DJ) phase perovskite. However, the heat transfer mechanisms in DJ phase perovskites are rarely reported. Herein, we determine thermal conductivities of (PDA)(FA)
n 
− 1Pb
n
I3n
 
+ 1 films with n = 1−6 by time-domain thermoreflectance. The measured results indicate that the thermal conductivities of these films are extremely low, showing a trend from decline to rise with increasing n values, and reaching to the lowest when n = 2. We measure the propagation of acoustic phonons in films with n = 1−3 by time-domain Brillouin scattering and find phonon velocity plays a key role in the thermal conductivity, which can be explained by the mismatch of spring constants between the inorganic layer and the organic layer using the bead-spring model. The gradually increasing thermal conductivity for larger n values is attributed to the gradual transformation of the grain orientation from horizontal to vertical, which is demonstrated by the grazing-incidence wide-angle x ray scattering (GIWAXS) results. Our work deepens the understanding of the thermal transport process in 2D DJ phase perovskite films and provides insights into thermal management solutions for their devices.
Depth-prior-based LiDAR point cloud de-noising method leveraging range-gated imaging
Authors: Yang Zhaopeng , Liu Xiaoquan
Published: August 2024

Light Detection and Ranging (LiDAR) has been widely adopted in modern self-driving vehicles and mobile robotics, providing 3D information of the scene and surrounding objects. However, LiDAR systems suffer from many kinds of noise, and its noisy point clouds degrade downstream tasks. Existing LiDAR point cloud de-noising methods are time-consuming or cannot deal with the noise caused by occlusions or penetrating transparent surfaces. In this paper, we introduce a depth-prior-based LiDAR point clouds de-noising method to deal with all types of noise in LiDAR point clouds in real time. The depth prior is derived from the fundamental principles of range-gated imaging and divides the depth of field into three parts, which can provide an effective depth signal. The LiDAR point cloud, which is acquired in synchronization with gated images, is projected into a depth map, and points whose depth is inconsistent with the depth prior can be regarded as noise and can be removed, finally. We conduct an ablation study and compare the proposed method with existing de-noising methods using the Gated2Depth dataset, which is to our knowledge the first long-range-gated dataset specifically designed for 3D detection in adverse weather conditions and includes all the necessary data. The results demonstrated that the proposed method achieves superior performance across all metrics.
Computational ghost imaging enhanced by degradation models for under-sampling
Authors: Zhang Haoyu , Cao Jie , Cui Huan , Zhou Chang , Yao Haifeng , Hao Qun , Wang Yingbo
Published: August 2024

Computational ghost imaging (CGI) allows two-dimensional (2D) imaging by using spatial light modulators and bucket detectors. However, most CGI methods attempt to obtain 2D images through measurements with a single sampling ratio. Here, we propose a CGI method enhanced by degradation models for under-sampling, which can be reflected by results from measurements with different sampling ratios. We utilize results from low-sampling-ratio measurements and normal-sampling-ratio measurements to train the neural network for the degradation model, which is fitted through self-supervised learning. We obtain final results by importing normal-sampling-ratio results into the neural network with optimal parameters. We experimentally demonstrate improved results from the CGI method using degradation models for under-sampling. Our proposed method would promote the development of CGI in many applications.
Compact and broadband polarization beam splitter based on a bridged hybrid plasmonic waveguide coupler on a thin-film lithium niobate
Authors: Shen Xiwei , She Xuan , Huang Fei , Liu Hongshuo , Shu Xiaowu
Published: August 2024

We propose a compact and broadband polarization beam splitter (PBS) based on a thin-film lithium niobate. The hybrid plasmonic waveguide (HPW) is used as a bridge in a three-waveguide coupler to achieve large birefringence. A degree of phase-matching is introduced for optimization. The proposed PBS exhibits a 125-nm bandwidth (1495–1620 nm) of polarization extinction ratio (PER) over 20 dB or an 85-nm bandwidth (1515–1600 nm) of PER over 25 dB, with a device length of only 81 μm. An ultra-low insertion loss of 0.04 dB is achieved around the wavelength of 1550 nm. In addition, the proposed device exhibits high robustness of the fabrication tolerance.
Optical orbital angular momentum analogy to the Stern–Gerlach experiment
Authors: Dudley Angela , Sephton Bereneice , Nguyen Thien-An , Brady Nathan S. , Slussarenko Sergei , Alfano Robert R. , Forbes Andrew , Padgett Miles J. , Milione Giovanni , Lavery Martin P. J.
Published: August 2024

Symmetry breaking has been shown to reveal interesting phenomena in
physical systems. A notable example is the fundamental work of Otto
Stern and Walther Gerlach [Stern and Zerlach, Z. Physik 9,
349 (1922)10.1007/BF01326983] nearly 100 years ago
demonstrating a spin angular momentum (SAM) deflection that differed
from classical theory. Here we use non-separable states of SAM and
orbital angular momentum (OAM), known as vector vortex modes, to
demonstrate how a classical optics analogy can be used to reveal this
non-separability, reminiscent of the work carried out by Stern and
Gerlach. We show that by implementing a polarization insensitive
device to measure the OAM, the SAM states can be deflected to
spatially resolved positions.
Speckle reduced holographic display system with a jointly optimized rotating phase mask
Authors: Lee Eunbi , Jo Youngjin , Nam Seung-Woo , Chae Minseok , Chun Chen , Kim Youngjin , Jeong Yoonchan , Lee Byoungho
Published: August 2024

Speckle noise degrades image quality in systems with coherent light sources, which must be overcome in holographic displays. In this Letter, we introduce a holographic display system with a rotating phase mask for speckle noise reduction. The rotating phase mask works in a similar way as a conventional rotating diffuser, but its pattern is jointly optimized with the spatial light modulator to maintain the contrast of the reconstructed image. The effectiveness of our system is verified through both numerical simulations and a tabletop prototype, reducing the speckle contrast by 38.8% while preserving the image quality.
Citizen Developer als Katalysatoren für die Entwicklung mitarbeitergetriebener Innovationen
Authors: Leible Stephan , Simic Dejan , Gücük Gian-Luca , von Brackel-Schmidt Constantin
Published: August 2024

Die rasante Entwicklung digitaler Technologien hat den Bedarf an schneller und effizienter Softwareentwicklung in Organisationen verstärkt. In diesem Kontext haben No- und Low-Code Plattformen (NLCPs) transformative Potenziale entfaltet, indem sie Mitarbeitenden ohne umfassende Programmierkenntnisse und außerhalb der IT-Abteilung ermöglichen, eigenständig digitale Innovationen zu entwickeln. Diese Mitarbeitenden, als Citizen Developer (CD) bezeichnet, nutzen NLCPs als primäre digitale Tools, was Organisationen ermöglicht, ihre Innovationsfähigkeit durch den Einbezug von CD in das Konzept von mitarbeitergetriebenen Innovationen bottom-up zu fördern. Dieser Artikel untersucht die Problematik an der Schnittstelle zwischen Ideengenerierung und -umsetzung, bei der reguläre Mitarbeitende zwar Ideen entwickeln, diese aber mangels Programmierkenntnissen nicht ohne Unterstützung, beispielsweise der IT-Abteilung, umsetzen können. Durch eine systematische Literaturrecherche wurden die Befähigung von CD zur Entwicklung von mitarbeitergetriebenen Innovationen sowie die dabei auftretenden Wirkfaktoren analysiert. Zu den zentralen Erkenntnissen zählen die Identifizierung und Beschreibung von jeweils vier Förderfaktoren (zum Beispiel geringere Einstiegshürden) und Hemmfaktoren (zum Beispiel begrenzte Funktionalität von NLCPs) im Bottom-up-Entwicklungsprozess von CD. Zudem wurden fünf praxisorientierte Handlungsempfehlungen zur Integration von NLCPs für CD in Organisationen abgeleitet. Diese Empfehlungen umfassen die Etablierung eines IT-Governance-Rahmenwerks, die Förderung CD-unterstützender Organisationsstrukturen, der Sicherstellung von IT-Kollaboration und abteilungsübergreifender Zusammenarbeit sowie das Angebot von Schulungsmaßnahmen. Darüber hinaus wurden fünf Anwendungsbereiche generativer künstlicher Intelligenz ermittelt, die CD unterstützen und befähigen können. Diese umfassen die Beschreibung und Generierung von Programmcode, die Erstellung von Prototypen(-designs), die Automatisierung von Routineaufgaben sowie die Unterstützung kreativer Prozesse zur Lösungsfindung.
Fast-spiking interneuron detonation drives high-fidelity inhibition in the olfactory bulb
Authors: Burton Shawn D. , Malyshko Christina M. , Urban Nathaniel N.
Published: August 2024

Inhibitory circuits in the mammalian olfactory bulb (OB) dynamically reformat olfactory information as it propagates from peripheral receptors to downstream cortex. To gain mechanistic insight into how specific OB interneuron types support this sensory processing, we examine unitary synaptic interactions between excitatory mitral and tufted cells (MTCs), the OB projection neurons, and a conserved population of anaxonic external plexiform layer interneurons (EPL-INs) using pair and quartet whole-cell recordings in acute mouse brain slices. Physiological, morphological, neurochemical, and synaptic analyses divide EPL-INs into distinct subtypes and reveal that parvalbumin-expressing fast-spiking EPL-INs (FSIs) perisomatically innervate MTCs with release-competent dendrites and synaptically detonate to mediate fast, short-latency recurrent and lateral inhibition. Sparse MTC synchronization supralinearly increases this high-fidelity inhibition, while sensory afferent activation combined with single-cell silencing reveals that individual FSIs account for a substantial fraction of total network-driven MTC lateral inhibition. OB output is thus powerfully shaped by detonation-driven high-fidelity perisomatic inhibition.