bluuebunny/crossref_metadata_2025 huggingface dataset:
Lower Cranial Nerve Schwannomas: Cohort Study and Systematic Review
Authors: Carlstrom Lucas P. , Bauman Megan M. J. , Oushy Soliman , Perry Avital , Brown Paul D. , Peris-Celda Maria , Van Gompel Jamie J. , Graffeo Christopher S. , Link Michael J.
Published: October 2023

BACKGROUND AND OBJECTIVES:

Schwannomas originating from the lower cranial nerves (LCNS) are rare and pose a significant surgical challenge. Resection is the mainstay treatment; however, risk of treatment morbidity is considerable, and the available literature regarding differential treatment outcomes in this vulnerable population is sparse.

METHODS:

A single-institution cohort study and systematic literature review of LCNS were performed.

RESULTS:

Fifty-eight patients were included: 34 underwent surgical resection and 24 underwent stereotactic radiosurgery (SRS). The median age at diagnosis was 48 years (range 17-74). Presenting symptoms were dysphagia (63%), dysarthria/hypophonia (47%), imbalance (33%), and hearing loss/tinnitus (30%). Tumor size was associated with surgical resection, as compared with initial SRS (4.1 cm vs 1.5 cm, P = .0001). Gross total resection was obtained in 52%, with tumor remnants predominantly localized to the jugular foramen (62%). Post-treatment worsening of symptoms occurred in 68% of surgical and 29% of SRS patients (P = .003). Postoperative symptoms were mostly commonly hypophonia/hoarseness (63%) and dysphagia (59%). Seven patients (29%) had new neurological issues after SRS treatment, but symptoms were overall milder. The median follow-up was 60 months (range 12-252); 98% demonstrated meaningful clinical improvement. Eighteen surgical patients (53%) underwent adjuvant radiation at a median of 5 months after resection (range 2-32). At follow-up, tumor control was 97% in the surgical cohort and 96% among SRS patients.

CONCLUSION:

Although LCNS resection is potentially morbid, most postoperative deficits are transient, and patients achieve excellent tumor control—particularly when paired with adjuvant SRS. For minimally symptomatic patients undergoing surgical intervention, we advise maximally safe resection with intracapsular dissection to preserve nerve integrity where possible. For residual or as a primary treatment modality, SRS is associated with low morbidity and high rates of long-term tumor control.
On-Call Workload Differences in Neurosurgery: Resident Call “Weather” and a Departure from Colored Cloud Labels
Authors: Tan Hao , Bowden Stephen G. , Siler Dominic A. , O'Neill Brannan E. , Shahin Maryam N. , Fecker Adeline L. , Fleming-Sheffels Samantha , Han Seunggu Jude , Selden Nathan R. , Winer Jesse , Orina Josiah N.
Published: October 2023

BACKGROUND AND OBJECTIVES:

Labeling residents as “black” or “white” clouds based on perceived or presumed workloads is a timeworn custom across medical training and practice. Previous studies examining whether such perceptions align with objective workload patterns have offered conflicting results. We assessed whether such peer-assigned labels were associated with between-resident differences in objective, on-call workload metrics in three classes of neurosurgery junior residents. In doing so, we introduce more inclusive terminology for perceived differences in workload metrics.

METHODS:

Residents were instructed to complete surveys to identify “sunny”, “neutral”, and “stormy” residents, reflecting least to greatest perceived workloads, of their respective classes. We retrospectively reviewed department and electronic medical records to record volume of on-call work over the first 4 months of each resident's 2nd postgraduate academic year. Inter-rater agreement of survey responses was measured using Fleiss' kappa. All statistical analyses were performed with a significance threshold of P < .05.

RESULTS:

Across all classes, there was strong inter-rater agreement in the identification of stormy and sunny residents (Kappa = 1.000, P = .003). While differences in on-call workload measures existed within each class, “weather” designations did not consistently reflect these differences. There were significant intraclass differences in per shift consult volume in two classes (P = .035 and P = .009); however, consult volume corresponded to a resident's weather designations in only one class. Stormy residents generally saw more emergencies and, in 2 classes, performed more bedside procedures than their peers.

CONCLUSION:

Significant differences in objective on-call experience exist between junior neurosurgery residents. Self- and peer-assigned weather labels did not consistently align with a pattern of these differences, suggesting that other factors contribute to such labels.
Effectiveness of resveratrol as a hepatoprotector in a rat model of paracetamol-induced liver injury
Authors: Dezena Renan Marcel Bonilha , Schiavon Sthéfani , Landi Matheus Arnosti , Da Silva Gustavo Henrique , Gonçalves Gisele Mara Silva
Published: October 2023

Objective: Evaluate the effectiveness of resveratrol as a hepatoprotector in a rat model of paracetamol-induced liver injury and its biodistribution to understand its pharmacokinetics. Methodology: As an experimental approach, animals were divided into the test group with 4 subgroups and the control group with 4 subgroups. Animals of the "treated" group were subjected to resveratrol pre-treatment for eight days, followed by intoxication with a high dose of paracetamol on the 8th day. Animals were euthanized to collect the blood and liver tissue samples 24 and 72 h after the last administration. Hepatoprotective activity was evaluated through serum levels of glycogen and hepatic enzymes, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP), histological and morphometric analysis of the liver tissue. For biodistribution analysis, different organs (organs, kidneys, heart and lungs) were collected and macerated, and resveratrol was quantified using high-performance liquid chromatography. Statistical analyses of morphometry, transaminases and alkaline phosphatase measurements, and biodistribution results were performed using GraphPad Prism® 3.0. Differences between groups were compared using ANOVA, followed by the Bonferroni test. Statistical significance was set at p < 0.05.
Does endogenous feline leukemia virus occur as a risk factor?: A molecular characterization study from Türkiye
Authors: Koç BT , Oğuzoğlu TÇ
Published: October 2023

Feline leukemia virus (FeLV) is a feline retrovirus that causes various effects on cat health. FeLV, along with other retroviruses, has altered in terms of molecular structure and pathogenetic and clinical status due to integration into the host genome. In this study, we aimed to determine the presence of enFeLV in the indoor-cats and provide a comparison with potential exFeLV prevalence. Additionally, we aimed to investigate the relationship between positive cases of enFeLV and risk factors including age, gender, breed. We collected 200 samples from domestic cats in Turkey for molecular diagnosis and characterization of en- or exFeLV. Amplified products were purified and sequenced using the Sanger method. According to the phylogenetic tree, our sequences constituted two main clusters that were divergent from each other in Group-2 enFeLVs. The unit of “Health status” in the overall population comprised 161 healthy and 39 diseased cats according to clinical diagnosis. In diseased cats, 17 were found to be enFeLV positive (17/39; 43.6%). “Gender”, “age”, and “breed” were not found to be risk factors for the presence of enFeLV among domestic cats in this study. With regards to the outcomes of the study, we submit that both variants of FeLV should be tested prior to initiating a vaccination program.
A Bioconductor workflow for processing, evaluating, and interpreting expression proteomics data
Authors: Hutchings Charlotte , Dawson Charlotte S. , Krueger Thomas , Lilley Kathryn S. , Breckels Lisa M.
Published: October 2023

Background: Expression proteomics involves the global evaluation of protein abundances within a system. In turn, differential expression analysis can be used to investigate changes in protein abundance upon perturbation to such a system. Methods: Here, we provide a workflow for the processing, analysis and interpretation of quantitative mass spectrometry-based expression proteomics data. This workflow utilizes open-source R software packages from the Bioconductor project and guides users end-to-end and step-by-step through every stage of the analyses. As a use-case we generated expression proteomics data from HEK293 cells with and without a treatment. Of note, the experiment included cellular proteins labelled using tandem mass tag (TMT) technology and secreted proteins quantified using label-free quantitation (LFQ). Results: The workflow explains the software infrastructure before focusing on data import, pre-processing and quality control. This is done individually for TMT and LFQ datasets. The application of statistical differential expression analysis is demonstrated, followed by interpretation via gene ontology enrichment analysis. Conclusions: A comprehensive workflow for the processing, analysis and interpretation of expression proteomics is presented. The workflow is a valuable resource for the proteomics community and specifically beginners who are at least familiar with R who wish to understand and make data-driven decisions with regards to their analyses.
Models for the retention of duplicate genes and their biological underpinnings
Authors: Assis Raquel , Conant Gavin , Holland Barbara , Liberles David A. , O'Reilly Malgorzata M. , Wilson Amanda E.
Published: October 2023

Gene content in genomes changes through several different processes, with gene duplication being an important contributor to such changes. Gene duplication occurs over a range of scales from individual genes to whole genomes, and the dynamics of this process can be context dependent. Still, there are rules by which genes are retained or lost from genomes after duplication, and probabilistic modeling has enabled characterization of these rules, including their context-dependence. Here, we describe the biology and corresponding mathematical models that are used to understand duplicate gene retention and its contribution to the set of biochemical functions encoded in a genome.
A narrative review of adaptive testing and its application to medical education
Authors: Burr Steven A. , Gale Thomas , Kisielewska Jolanta , Millin Paul , Pêgo José M. , Pinter Gergo , Robinson Iain M. , Zahra Daniel
Published: October 2023

Adaptive testing has a long but largely unrecognized history. The advent of computer-based testing has created new opportunities to incorporate adaptive testing into conventional programmes of study. Relatively recently software has been developed that can automate the delivery of summative assessments that adapt by difficulty or content. Both types of adaptive testing require a large item bank that has been suitably quality assured. Adaptive testing by difficulty enables more reliable evaluation of individual candidate performance, although at the expense of transparency in decision making, and requiring unidirectional navigation. Adaptive testing by content enables reduction in compensation and targeted individual support to enable assurance of performance in all the required outcomes, although at the expense of discovery learning. With both types of adaptive testing, candidates are presented a different set of items to each other, and there is the potential for that to be perceived as unfair. However, when candidates of different abilities receive the same items, they may receive too many they can answer with ease, or too many that are too difficult to answer. Both situations may be considered unfair as neither provides the opportunity to demonstrate what they know. Adapting by difficulty addresses this. Similarly, when everyone is presented with the same items, but answer different items incorrectly, not providing individualized support and opportunity to demonstrate performance in all the required outcomes by revisiting content previously answered incorrectly could also be considered unfair; a point addressed when adapting by content. We review the educational rationale behind the evolution of adaptive testing and consider its inherent strengths and limitations. We explore the continuous pursuit of improvement of examination methodology and how software can facilitate personalized assessment. We highlight how this can serve as a catalyst for learning and refinement of curricula; fostering engagement of learner and educator alike.
New trends in science communication fostering evidence-informed policymaking
Authors: Szüdi Gábor , Bartar Pamela , Weiss Gorazd , Pellegrini Giuseppe , Tulin Marina , Oomen Tessa
Published: October 2023

This article aims to assess novel trends in science communication relating to how policymakers in the field of innovation and digitalisation policy consume and use scientific findings. We investigate the mutual influence that science communication and policy have on each other and answer the question how emerging science communication trends in the science-policy nexus might influence the use of scientific findings in the policymaking process. By using Google and the largest scholarly repositories, Google Scholar, ResearchGate, and Academia.edu, from 1st March to 31st May 2020, we reviewed policy documents and academic literature containing relevant information on the evolution of characteristics of global, European, and national science communication activities and the interrelated policy responses to identify the most relevant current trends in the evidence-to-policy process alongside three key challenges; trust, translation, and timing. The three identified main trends are (1) a stronger engagement between science and policy, (2) more open, reliable, and accountable science communication practices with policymakers, and (3) the increasing digitalisation and visualisation of science communication. We deepened our investigation by conducting online semi-structured interviews with relevant policy stakeholders at the international and national level between 1st May and 31st July 2020. With the support of the European Commission and building on the existing network of partners, we identified decision-makers and advisors with relevant experience in fields related to innovation and digitalisation policy working in four countries that represent different levels of generalized social trust: Austria, Italy, Hungary, and the Netherlands, and at the international/European Union level. After an online consultation process with a global set of policymakers, these theoretical findings were translated to policy recommendations showcasing possible solutions in science communication that may be initiated, strengthened, or continued by policy stakeholders in order to reach a more effective and efficient uptake of scientific findings in evidence-informed policymaking.
GROWTH REGULATORS THAT INCREASE SOYAN PRODUCTIVITY
Authors: Daminova Anisa , Sibgatullova Adylya
Published: October 2023

Plant growth regulators have a wide spectrum of physiological activity. Thanks to their action, resistance of soybean plants to adverse environmental factors, diseases, growth, development and quality is observed. Soy is the most widely used oilseed in the world. The world annual production of soybeans exceeds 260 million tons. It is the main edible plant and the main source of vegetable protein worldwide.The global demand for soybeans is constantly growing as its seeds provide essential proteins, oils and nutraceuticals. In an effort to meet the increased demand for this crop, it has become necessary to introduce cultural practices that promote adaptation to difficult environmental conditions, can improve soybean tolerance to abiotic stress and increase yields. Plant growth regulators are mainly used for this purpose due to their critical role in plant growth and development. One of the main growth regulators are such phytohormones as: auxins, gibberellins, cytokinins, brassinolides, ethylene, abscisic and jasmonic acid. Each of the groups of phytohormones produces its own characteristic action, which is similar in plants of different species. Cell division and elongation, which underlie all processes of growth and morphogenesis, are under the control of auxins and cytokines in plants, so their complete absence can lead to death. These compounds generally have a positive effect on the morphology, physiology and quality of the soybean crop. They are also able to regulate and control to a large extent the processes of growth and differentiation of plant cells. It should be noted that these phytohormones are required in small amounts for the activation and regulation of morphogenetic processes in soybean and other agricultural plants.
Conjunto de Boas Práticas Baseadas na Avaliação de Risco para a Padronização Nacional em Ambientes Computacionais
Authors: Henriques Felipe da Rocha , Viana Filho Carlos Roberto Gonçalves , Lintomen Marcelo , Teles Carlos Alberto Martins de Souza , De Assis Laura Silva
Published: October 2023

Atualmente, homens, empresas privadas e públicas, junto com vários dispositivos, têm estado cada vez mais conectados. Esse cenário, no entanto, exige maiores responsabilidades relacionadas à segurança, uma vez que vulnerabilidades em computadores pessoais, servidores, softwares e dispositivos podem expor dados pessoais, fornecer desvios financeiros, interromper a produção, colocando em risco a segurança da infraestrutura crítica de países. No Brasil, a aprovação da nova lei brasileira de proteção de dados torna a segurança crucial e parte dos requisitos iniciais para o desenvolvimento ou manutenção de um sistema. Assim, a validação desses requisitos para certificar seu cumprimento da solicitação se torna de grande importância. Neste trabalho, propomos uma padronização para o cenário brasileiro para avaliação de riscos em ambientes computacionais. Considera-se uma metanálise para avaliar a proposta e, com base nos resultados obtidos, verificamos que a adaptação de padrões internacionais para o cenário brasileiro é uma boa alternativa para implantação em larga escala, o que pode levar à redução de custo e tempo para empresas.
Using shape-memory alloy staples to treat comminuted manubrium sterni fractures: A case report
Authors: Zhang Min , Jiang Wei , Wang Ze-Xue , Zhou Zhi-Ming
Published: October 2023

Rehabilitation of lower limb amputation in developing countries is quite challenging. Though there are basic to highly advanced prostheses available in India, the set-up is still facing difficulties in developing countries. Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations. In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India. Currently, India is advancing well in the rehabilitation field, but further studies are required to provide more evidence and recommendation.
Gouty tenosynovitis with compartment syndrome in the hand: A case report
Authors: Lee Dong Yun , Eo SuRak , Lim SooA , Yoon Jung Soo
Published: October 2023

Rehabilitation of lower limb amputation in developing countries is quite challenging. Though there are basic to highly advanced prostheses available in India, the set-up is still facing difficulties in developing countries. Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations. In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India. Currently, India is advancing well in the rehabilitation field, but further studies are required to provide more evidence and recommendation.
Application of the Analytic Hierarchy Process for Solving Social Wicked Problems
Authors: Minutolo Marcel
Published: October 2023

It is my pleasure to be guest editor for the special topics section of the International Symposium of the Analytic Hierarchy Process (ISAHP2022). Peer-reviewed papers from this symposium will be published in IJAHP in the special topics section of this issue and following issues as they become accepted for publication. In listening to the speakers at the 2022 International Symposium of the Analytic Hierarchy Process, it became clear how many of society’s problems are “wicked” and in need of a rigorous process whereby they can be disaggregated and discussed without involving stakeholders’ emotions. Many of the social challenges that the world faces today are “wicked problems” as defined by Camillus (2016). The term "wicked problem" was coined by Rittel and Webber (1973). It refers to complex and ill-structured problems that are difficult to define, have multiple interrelated causes and effects, and often lack a clear solution. Understanding wicked problems is crucial, as they often involve issues related to sustainability, environmental, social and governance (ESG) concerns, and conflict resolution.  Wicked problems are characterized by several key attributes that make them particularly challenging to solve.
In Permanent Evolution: An Epilogue
Authors: Wardaya Baskara T.
Published: October 2023

Abstract: Using Pierre Nora's notion (1989) that memory "remains in permanent evolution, open to the dialectic of remembering and forgetting, … vulnerable to manipulation and appropriation, susceptible to being long dormant and periodically revived," this paper demonstrates that memories of Indonesia's anti-communist purge beginning in 1965 continue to fluctuate between remembering and forgetting. While vulnerable to manipulation and appropriation, memories of the purge are also susceptible to periods of dormancy and revival. Against this backdrop, members of the Indonesian civil society attempt to produce "different kinds of memories" of the purge. They pursue the attempts through different kinds of initiatives, including music, art performances, studies on demographic changes, and hosting educational fora. Further research is needed to explore similar initiatives to study how the permanent evolution of the memories of the 1965-66 purge continues to produce negotiation between the purge's different narratives and their respective adherents.
Futures of Care: Care Technologies and Graphic Medicine
Authors: Venkatesan Sathyaraj , Ancy A Livine
Published: October 2023

abstract: Assistive care technologies, developed to replace, support, or extend human capabilities and to address the surging demands of care, have been gaining prominence recently. The current trend summons a posthuman approach through decentering the privileged role of humans in several spaces of caregiving, such as hospitals and eldercare homes. The existence of these cutting-edge assistive technologies, exciting as they are, hints at a possible future when the distinction between humans and technology will be blurred, thus transforming care relations. However, these technological advances carry equal promises and dangers. While care robots may reduce the burden of caregiving, they also threaten to minimize human contact with vulnerable populations. This critical assessment reviews technological advances in care and close-reads several single-panel cartoons to theorize the impact of technologies on caring relations. The article also examines the neoliberal underpinnings of such technologies and the moral dangers of their unreflective use.
Apophenic Inventions: Chance and the Dismantling of Anthropocentrism in Stanisław Lem’s Fiction
Authors: Bartolotta Simona
Published: October 2023

ABSTRACT: This paper examines how Stanisław Lem’s speculative writings configure the idea of chance as a challenge to anthropocentric thinking. Texts examined include tales from The Cyberiad , one of the faux reviews from A Perfect Vacuum , and Lem’s two detective novels The Investigation and The Chain of Chance —which, as the paper argues, in fact fully participate in the same cognitive tasks that in Lem’s literary-philosophical system are attributed to science fiction, concerning the expansion of possibilities of thought and the questioning, and possibly even the reinvention, of ingrained ideas and conceptions. By analysing the structural and theoretical role that chance plays in these texts, and chiefly drawing from scientific and philosophical application of probability theory, this paper demonstrates that Lem’s thought and oeuvre pivot on a complex web of connections between the idea of chance, the limits of anthropocentrism, and the question of tellability.
Analysis of the effect of optical thickness on polarization in a sea fog stratified environment
Authors: Bai Xuemei , Qu Ying , Duan Jin , Xie Guofang , Fu Qiang , Zhang Su , Zhan Juntong
Published: October 2023

Since there are usually multiple layers present in a real-world sea fog environment, and because previous studies have tended to analyze sea fog as a single layer rather than as refined layered sea fog, this paper splits sea fog into two categories: water fog and salt fog double-layer environments. By adjusting the optical thickness of the two layers of media, we may investigate the issue of the law governing the transmission of polarized light. In this paper, the analysis is mainly carried out through a simulation and experimental tests. The simulation portion is based mostly on the improved layered Monte Carlo approach, which builds a simulation model more appropriate for multilayer non-spherical media by using the accumulation principle to determine the scattering and transmission properties between layers. The tests are conducted by altering the double-layer medium’s optical thickness, incoming wavelength, and polarization state, and then getting the polarization information of visible light after transmission through the complicated environment. The findings demonstrate that the optical thickness of the sea fog double-layer media affects polarized light transmission in a non-negligible way. Longer wavelength polarized light may keep polarization information better as the optical thickness increases, and circularly polarized light has polarization-preserving properties that are superior to linearly polarized light. By contrasting the simulation findings with the experimental data, the consistency of the two conclusions is confirmed, and the study offers a helpful resource for the transmission of polarized light in the sea fog environment.
Super-resolution imaging through scattering media based on improved triple correlation recursion and deterministic iterative estimation
Authors: Liu Yang , Cui Guangmang , Shi Shigong , Xiang Qinlei , Zhao Jufeng , Hou Changlun
Published: October 2023

Iterative phase retrieval algorithms are commonly used in computational techniques and optimization methods to obtain the reconstruction of objects hidden behind opaque scattering media. However, these methods are susceptible to converging to incorrect local minima, and the calculation results tend to be unstable. In this paper, a triple-correlation-based super-resolution imaging (TCSI) framework is proposed to achieve single-shot imaging of unknown objects hidden behind the scattering medium. The amplitude spectrum of the object is obtained by a speckle correlation (SC) method. Iterative relaxation recursion (IRR) sufficiently extracts object information from the triple correlation (TC) of the speckle patterns, serving as the prior initial guess for the iterative estimation algorithm (IE) to obtain a deterministic phase spectrum. Blur correction (BC) is then applied to the diffraction-limited image to achieve super-resolution imaging. Experimental results demonstrate that the flexible framework could effectively overcome the influence of speckle resolution and outperform traditional methods in terms of performance. Our approach provides a basis for non-invasively visualizing various samples behind scattering media.
Optimization technology for DCF dispersion compensation based on cascaded fiber Bragg grating
Authors: Wang Chong , Zhou Mengting , Song Kun , Li Miaomiao , Yi Yi , Wu Jiahui
Published: October 2023

A cascaded fiber Bragg grating (FBG) structure is proposed to reduce
the dispersion of optical signals in single-mode fibers. Using the
OptiSystem software for simulation, the three compensation schemes
(precompensation, postcompensation, and symmetric compensation) of
dispersion-compensated optical fiber (DCF) are analyzed, and the
results show that the best of the three schemes is the
postcompensation structure. For the postcompensation scheme, the
influence of the coding method and duty cycle on the system is
analyzed, and then the fiber grating is cascaded behind the
transmitter to obtain a narrow linewidth of the optical signal and
minimize the reflectivity sidelobe, and a chirped fiber grating is
connected in front of the receiver to compensate for the dispersion of
the channel residue. With or without cascaded FBGs, system performance
at different input powers and different transmission distances is
discussed. The results show that cascading fiber gratings can improve
the performance of the system.
High-accuracy reconstruction of Stokes vectors via spatially modulated polarimetry using deep learning at low light field
Authors: Zhang Xinxin , Liu Lihui , Li Yanqiu , Ning Tianlei , Zhao Zhe
Published: October 2023

Polarization measurement is generally performed in scenes with a low signal-to-noise ratio (SNR) such as remote sensing and biological tissue detection. The spatially modulated polarimeter can satisfy the real-time measurement requirements in low SNR scenes by establishing the mapping between photon spatial distribution and polarization information. However, accurately measuring the polarization state under low-light illumination becomes highly challenging owing to the interference of background noise. In this paper, a deep learning method is proposed and applied to the high-accuracy reconstruction of polarization information at low light field. A reinforced two-layer deep convolutional neural network is designed to respectively extract global and local features of noise in this method. Accurate photon spatial distribution can be obtained by fusing and processing these features. Experimental results illustrate the excellent accuracy achieved by the proposed method with a maximum average value of the absolute measured error below 0.04. More importantly, the proposed method is well-performed for the reconstruction of Stokes vectors at low light fields of various levels without requiring changes to the model, enhancing its practicality and simplicity.
Method for a deflection-type refractometer measuring the fringe shift by using linear Fresnel zone plates
Authors: Amani Alireza , Tan YiDong
Published: October 2023

This study describes the design and performance of a deflection-type refractometer based on measuring the fringe shift from the Fresnel diffraction pattern to solve some major limitations of conventional differential refractometers, such as measurement range, resolution, zero balancing, and monitoring analysis. The refractometer apparatus comprises a coherent light source, linear Fresnel zone plate, measuring cell, and image capture device mounted on a movable platform. The distance measurement unit is configured to detect fringe deflection due to the difference in refractive index between the sample and the reference. To achieve this, distance measurements with an accuracy of a few nanometers by using the local frequency method and fringe shift measurement method are quite feasible. The uncertainty in this technique is determined by the smallest change in the longitudinal displacement of the image for which the CCD camera can detect a change in pixel position. The refractive index is obtained with a highly extended measurement range of at least ±0.4RIU and precision of the order of 2×10−4RIU. A numerical comparison between computer simulation of the diffraction patterns that occur when the linear Fresnel zone plate is illuminated by a plane light traveling parallel to thezaxis.
Photonic beamforming using a quantum-dash optical frequency comb source
Authors: Xie Yuxuan , Khalil Mostafa , Sun Hao , Moosabhoy Sehr , Liu Jiaren , Lu Zhenguo , Poole Philip J. , Weber John , Chen Lawrence R.
Published: October 2023

We demonstrate photonic beamforming using a quantum-dash (QD) optical
frequency comb (OFC) source.
Thanks to the 25 GHz free
spectral range (FSR) and up to 40 comb lines available from the QD
OFC, we can implement phased antenna arrays (PAAs) with directional
radiation and scanning. We consider two types of PAAs: a uniform
linear array (ULA) and a uniform planar array (UPA). By selecting
different comb lines with a programmable optical filter, we can tune
the FSR of the OFC source and realize a discrete scanning function. We
evaluate the beam squint of the ULAs, and the results show that we can
achieve broadband operation. Finally, we show that we can achieve both
directional radiation and scanning simultaneously using the UPA.
TE/TM mode electro-optic conversion based on a titanium diffusion lithium niobate waveguide with a polarization-maintained fiber structure
Authors: Li Yang , Yang Zuoxin , Chen Huajiang , Liu Runhao , Peng Jiahao , Fu Fangheng , Yang Tiefeng , Guan Heyuan , Yang Xu , Di Hongwei , Lu Huihui
Published: October 2023

For the development of photonic integrated circuits and lithium niobate (LiNbO3, LN) optical waveguide technology, the implementation and application of polarization devices based on LN are also becoming more widespread, where titanium (Ti)-diffused LN waveguides form the basis of many important electro-optic (EO) integrated optical devices. Moreover, utilizing polarization conversion has the potential to enhance both the effectiveness and capacity of optical transmission. Thus, we have presented an EO polarization mode converter packaging with PANDA polarization-maintaining optical fibers (PMFs) in the broadband wavelength range (1440–1620 nm) to obtain the multiwavelength modulation, featuring the wavelength tunability. Additionally, the fabricated device is able to achieve transverse electric (TE) to transverse magnetic (TM) mode conversion efficiently with the applied voltage of  ±, which provides high conversion efficiency. Importantly, our device also features a high-frequency response of about 600 MHz with overall insertion loss below 5 dB. The rapid development of LN-based polarization devices holds great promise for chip-integrated systems in the field of polarization telecommunication.
Quasi-TPPs/Fano resonance systems based on an MDM waveguide structure and its sensing application
Authors: Lu Yunqing , Zhou Yongqiang , Cheng Di , Li Mengmeng , Xu Yuexin , Xu Ji , Wang Jin
Published: October 2023

In this paper, quasi-Tamm plasmon polaritons (TPPs)/Fano resonance systems based on metal–dielectric–metal (MDM) waveguides are proposed. TPPs are surface electromagnetic modes formed at the interface between a metal and a one-dimensional dielectric photonic crystal (PhC). A metal plasmonic Bragg reflector (PBR) in a MDM waveguide is equivalent to a dielectric PhC, which is realized by periodic MDM waveguide width modulation and leads to the photonic bandgap. By introducing a thin Ag baffle and a PBR in MDM waveguide core, the quasi-TPPs are excited at the interface between the Ag baffle and the PBR, when the phase-matching condition is met. The proposed structure can be fabricated with focused ion beam or electron beam direct-writing lithography, avoiding complex fabrication procedures of manufacturing dielectric PhC by filling the MDM waveguide core with different dielectric materials. Furthermore, an MDM waveguide side-coupled resonator system is constructed to generate Fano resonance by placing a PBR on the side of the MDM waveguide and an Ag baffle in the waveguide core. The Fano resonance originates from the interference between a broad continuum state provided by the Ag baffle and a discrete state provided by quasi-TPPs. The sensing performance of the Fano resonance system is investigated. In this design, the open PBR structure replaces the traditional closed resonant cavity, which makes it more convenient to contact with analytes. The numerical simulations demonstrate that a high sensitivity of 1500 nm/RIU and figure of merit value of 4.08×105 are achieved.
Enhancing the external quantum efficiency of Schottky barrier photodetectors through thin copper films
Authors: Seok Jongeun , Jin Yeonghoon , Yu Kyoungsik
Published: October 2023

Silicon-based Schottky barrier photodetectors (SBPDs) are a cost-effective alternative to compound semiconductor-based photodetectors by extending the silicon’s photodetection range to the near-infrared (NIR) region. However, SBPDs still suffer from low quantum yield due to poor absorption in a metal layer and low emission efficiency of hot electrons. This study investigates the use of thin copper (Cu) films as a means of improving the performance of SBPDs operating in the NIR region. Our results show that thin-film Cu SBPDs present a higher external quantum efficiency (EQE) compared to other metal SBPDs due to their low Schottky barrier height and long mean free path. Notably, at a bias of −3 V, the thinnest Cu SBPDs exhibit an EQE of the order of 1% at 1510 nm.
Transmission of optical communication signals through ring core fiber using perfect vortex beams
Authors: Villalba Nelson , Melo Cristóbal , Ayala Sebastián , Mancilla Christopher , Valenzuela Wladimir , Figueroa Miguel , Baradit Erik , Lin Riu , Tang Ming , Walborn Stephen P. , Lima Gustavo , Saavedra Gabriel , Cañas Gustavo
Published: October 2023

Orbital angular momentum can be used to implement high capacity data transmission systems that can be applied for classical and quantum communications. Here we experimentally study the generation and transmission properties of the so-called perfect vortex beams and the Laguerre-Gaussian beams in ring-core optical fibers. Our results show that when using a single preparation stage, the perfect vortex beams present less ring-radius variation that allows coupling of higher optical power into a ring core fiber. These results lead to lower power requirements to establish fiber-based communications links using orbital angular momentum and set the stage for future implementations of high-dimensional quantum communication over space division multiplexing fibers.
FDM-assisted opposite two-way OA-CEAS system employing four lasers for simultaneous multi-species detection
Authors: Gao Guangzhen , Yang Yubing , Wang Xuan , Yang Hui , Cai Tingdong
Published: October 2023

An FDM-assisted opposite two-way OA-CEAS system is reported in this paper. Compared with the traditional OA-CEAS system with one-way transmission configuration, the new system has two main advantages. One of the advantages is that four lasers can be employed for simultaneous measurements of multiple species in this system. Another advantage is the combination of the silver-coated concave spherical mirror and the narrow bandpass filter employed to realize the opposite two-way transmission in the optical cavity which can also serve as a re-injection mirror and optical enhancement gotten for free in the system. The performance of the system is demonstrated by simultaneous measurements of CO, CO2, C2H4, and CH4. This work highlights a new strategy for simultaneous detection by using four lasers in a single optical integrated cavity, which can improve the utilization rate of the optical cavity and reduce the cost for multiple gas species sensing.
Quantum-dot color wheel for projection displays
Authors: Yan Yinguo , Xiao Yuze , Cai Junhu , Zhang Yushuo , Ye Yun , Xu Sheng , Yan Qun , Guo Tailiang , Chen Enguo
Published: October 2023

A color wheel (CW) is one of the most essential devices for
contemporary projection displays because it provides the color
initialization definition and determines the color performance of the
whole system. However, conventional color wheels remain limited in
terms of color performance and efficiency because of the
light-absorbing material and time sequential color generation. Quantum
dots, found in 1981 and known as a kind of quasi-zero-dimensional
nanomaterial, exhibit excellent features for displays due to their
quantum confinement effect, which won the 2023 Nobel Prize in
Chemistry. Inspired by this, the paper systematically demonstrates a
quantum-dot color wheel (QD-CW) device through theoretical derivation,
simulation analysis, and experimental verification. The theoretical
model to define the duty circle ratio is presented for the QD-CW and
verified by Monte Carlo ray-tracing simulation. In terms of
experimental verification, the QD-CW device is realized by multiple
rounds of a photolithography process, and then assembled into a blue
laser pumped projection prototype for full-color display. The
chromaticity coordinates of white-balanced output are finally located
at (0.317,0.338), which matches well with a standard D65 source. The
color gamut area of the QD-CW device reaches 116.6% NTSC, and the
average light conversion efficiency (LCE) of the prepared QD-CW is
57.0%. The proposed QD-CW device has ∼40% higher color gamut area and 1.2× higher LCE than a conventional CW
device. These exciting findings show a groundbreaking approach to
color generation in projection displays, which are expected to shed
light on other high-quality display applications.
Voltage-tunable optical parametric oscillator with an alternating dispersion dimer integrated on a chip
Authors: Pidgayko Dmitry , Tusnin Aleksandr , Riemensberger Johann , Stroganov Anton , Tikan Alexey , Kippenberg Tobias J.
Published: October 2023

Optical parametric oscillators enable the conversion of pump light to new frequency bands using nonlinear optical processes. Recent advances in integrated nonlinear photonics have led to the creation of compact, chip-scale sources via Kerr-nonlinearity-induced parametric oscillations. While these sources have provided broadband wavelength tuning, the ability to tune the emission wavelength via dynamically altering the dispersion has not been attained so far. Here we present a voltage-tunable, on-chip integrated optical parametric oscillator based on an alternating-dispersion dimer, allowing us to tune the emission over nearly 20 THz near 1550 nm. Unlike previous approaches, our device eliminates the need for a widely tunable pump laser source and provides efficient pump filtering at the drop port of the auxiliary ring. Integration of this scheme on a chip opens up the possibility of compact and low-cost voltage-tunable parametric oscillators with diverse application possibilities.
Point-by-Point Compression of CO2 Infrared Laser for Fabrication of Waist-Enlarged Long Period Fiber Bragg Gratings
Authors: Yu Jia , Bai Chen , Zhang Weiguang , Mei Chao , Guo Zilong , Fan zhaojin , Tan Tan Zhenkun , Li Feng , Lv Jing , Guo Jiajun , yang liuqing
Published: October 2023

We propose a method using CO2 laser irradiation to heat and squeeze a standard SMF-28 fiber, forming long-period fiber gratings (LPFGs). By controlling the motor’s squeezing speed and time, we can increase the cladding diameter of optical fibers from 125 μm to a maximum of 160 μm. This expanded structure allows the formation of LPFGs with a minimum period length of 0.325 mm. This method produces LPFGs with larger waist diameters and shorter periods than traditional tapering methods, exhibiting more spectral transmission peaks with a maximum bandwidth less than 3 nm.
Health care workers’ perceptions and bias toward men as HIV clients in Malawi and Mozambique: A qualitative study
Authors: Dovel Kathryn , Paneno Rose , Balakasi Kelvin , Hubbard Julie , Magaço Amílcar , Phiri Khumbo , Coates Thomas , Cornell Morna
Published: October 2023

Men are underrepresented in HIV services throughout sub-Saharan Africa. Little is known about health care worker (HCW) perceptions of men as clients, which may directly affect the quality of care provided, and HCWs’ buy-in for male-specific interventions. Focus group discussions (FGDs) were conducted in 2016 with HCWs from 15 facilities across Malawi and Mozambique and were originally conducted to evaluate barriers to universal treatment (not HCW bias). FGDs were conducted in local languages, recorded, translated to English, and transcribed. For this study, we focused on HCW perceptions of men as HIV clients and any explicit bias against men, using inductive and deductive coding in Atlas.ti v.8, and analyzed using constant comparison methods. 20 FGDs with 154 HCWs working in HIV treatment clinics were included. Median age was 30 years, 59% were female, and 43% were providers versus support staff. HCWs held strong explicit bias against men as clients. Most HCWs believed men could easily navigate HIV services due to their elevated position within society, regardless of facility-level barriers faced. Men were described in pejorative terms as ill-informed and difficult clients who were absent from health systems. Men were largely seen as “bad clients” due to assumptions about men’s ‘selfish’ and ‘prideful’ nature, resulting in little HCW sympathy for men’s poor use of care. Our study highlights a strong explicit bias against men as HIV clients, even when gender and bias were not the focus of data collection. As a result, HCWs may have little motivation to implement male-specific interventions or improve provider-patient interactions with men. Framing men as problematic places undue responsibility on individual men while minimizing institutional barriers that uniquely affect them. Bias in local, national, and global discourses about men must be immediately addressed.
Evaluation of a device to detect neonatal hypothermia in a clinical setting in Ghana
Authors: McAbee Lauren , Mundagowa Paddington T. , Agbinko-Djobalar Babbel , Gyebi Owusu Prince , Sackey Adziri , Sagoe-Moses Isabel , Sacks Emma , Sakyi Kwame Sarfo , Dail Robin B. , Kanyangarara Mufaro
Published: October 2023

Neonatal hypothermia poses an increased risk of infection, hypoglycemia, metabolic dysfunction, and mortality, particularly in preterm or low birthweight (LBW) infants. However, early detection of hypothermia and prompt thermoregulation can mitigate these effects thus, the need for continuous neonatal temperature monitoring. The BEMPU TempWatch is a small bracelet designed for continuous temperature monitoring for neonates. When the body temperature falls below 36.5˚C, the bracelet generates an alarm sound and flashes an orange light, indicating hypothermia. This study aimed to assess the validity of the BEMPU TempWatch in detecting hypothermia in a clinical setting in Ghana using sensitivity and specificity. Additionally, the study sought to identify factors associated with misclassification using logistic regression analysis. A standardized questionnaire collected information about the mother, pregnancy, delivery, and neonate. The BEMPU TempWatch was placed on the wrist of the neonate, and over a 24-hour follow-up period, a nurse took 4-hourly axillary temperature readings using a digital thermometer. Whenever the device’s alarm sounded, a nurse immediately checked and recorded the axillary temperature, undertook necessary clinical actions, and rechecked after 30 minutes. Among the 249 neonates included in the study, 57.0% were female, 12.5% were extremely LBW, and 13.7% were extremely preterm. Based on 1,973 temperature readings, the sensitivity of the BEMPU TempWatch in detecting hypothermia was 67.8%, and the specificity was 95.9%. The sensitivity was lower among neonates being treated in incubators (58.4%) compared to those not (82.7%). Sensitivity was higher among neonates with LBW (1,500–2,500g) (73.5%) than very or extremely LBW neonates (<1,500g) (62.8%). The results showed that the BEMPU TempWatch had significantly fewer misclassifications among neonates who were not treated in an incubator, received only breastmilk, and were not born extremely preterm. Further studies are warranted to evaluate the effectiveness of the BEMPU TempWatch on neonatal health outcomes.