bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a postnatal period of interdependent neurogenesis and apoptosis in peripheral neurons
Authors: Kaminski Catherine L. , Banik Debarghya Dutta , Schmitd Ligia B. , Pierchala Brian A.
Published: November 2024

During neurogenesis, excessive numbers of neurons are produced in most regions of the central and peripheral nervous systems. Nonessential neurons are eliminated by apoptosis, or programmed cell death. This has been most thoroughly characterized in the peripheral nervous system (PNS) where targets of innervation play a key role in this process. As maturing neurons project axons towards their targets of innervation, they become dependent upon these targets for survival. Survival factors, also called neurotrophic factors, are produced by targets, inhibit apoptosis cascades, and promote further growth and differentiation. Because neurotrophic factors are limited, as is target size, neurons that do not correctly and efficiently innervate targets undergo apoptosis ( Levi-Montalcini, 1987; Davies, 1996). Thus, excessive neurogenesis acts to ensure that sufficient numbers of neurons are produced during development. In the superior cervical ganglion (SCG), this process of neurogenesis and subsequent apoptosis is reported to be complete by postnatal day 3-4 (P3-P4) in mice. Surprisingly, we observed significant numbers of apoptotic neurons out to P14, and neurogenesis was still present at P14 as well. In both the SCG and geniculate ganglion (GG), postnatal neurogenesis was dependent on apoptosis because little or no postnatal neurogenesis was observed in Bax-/- mice, in which apoptosis is eliminated. These results indicate that both neurogenesis and apoptosis continue to occur well after birth in peripheral ganglia, and that neurogenesis depends on apoptosis, suggesting that neurogenesis continues postnatally to replace neurons that are eliminated during synaptic refinement.
Relevance of Competency Based Education for Architectural Education in India
Authors: Kohale Nikhil , Kini Pradeep , Mohammed Ciraj
Published: November 2024

Background A holistic architectural education is the culmination of learning knowledge, skills, attitudes, and values, which eventually reflects in the quality of graduates. Even though different schools of thought have made various kinds of qualitative contributions towards the evolution of architectural education in India, it has largely been dominated by the quantitative and technical aspects of its regulating framework. Architects engage with the demanding contradictions between responsibilities of an ethical nature, the dynamic challenges of practice, and the intricacies of architectural imagination. The aesthetical and imaginative foundations of the field make it incumbent upon the architects to possess a balance of ecumenical proficiencies for accountability and personalization. The purpose of the study is to identify relevant attributes of Competency Based Education (CBE) that can be adopted for architectural education in India. Methods This research follows a narrative review approach and a descriptive-analytic method to broadly understand the attributes of CBE and its potential relevance to architectural education in India. 323 articles were searched on various search strings based on their relevance to the inquiry. 76 documents written in English language were included and appraised through the Scale of the Assessment for Narrative Review Articles (SANRA) tool to avoid any risk of bias. The PRISMA 2020 checklist and flow diagram has been used to report the findings of this narrative review. Result The study identifies eight critical parameters of CBE with respect to its definitions, origins, transitions, regulatory environment, characteristics, approaches and implications on teaching-learning, frameworks and models of assessment; and challenges, which makes a case for the relevance of CBE for architectural education in India, which hasn’t been explored yet. Conclusion The broader expectations of ‘being competent’ can be addressed through a conscious adoption of strategies of relevant attributes of CBE which can encourage building attitudes and temperament for life-long learning.
The macroeconomic determinants of trade openness in Latin American countries: A panel data analysis
Authors: Morán Santamaría Rogger Orlando , Llonto Caicedo Yefferson , Cúneo Fernández Francisco Eduardo , Nikolays Pedro Lizana Guevara , Percy Junior Castro Mejía , Pérez Pérez Milagros Judith , Vela Meléndez Lindon , Montenegro López Moises Elias
Published: November 2024

Background Trade openness shows a positive impact on economic growth, supported by economic theory, and export diversification and economic complexity show a positive dynamic in trade openness in the world; however, a specificity is generated in South American countries. Therefore, the objective of the research is to analyse the macroeconomic determinants of trade openness in Latin American countries. Methods The research approach was quantitative and explanatory using panel data methodology from the databases of the World Bank, Harvard University and the Economic Commission for Latin America and the Caribbean for the period 2000-2020. Results The fixed effects panel data model showed that the variables that had a negative impact on trade openness were GDP, the economic complexity index and the logistic performance index, while the variables that had a positive impact were exports of high-tech products (a proxy for innovation), exports, imports, research and development expenditure and interregional trade in goods. Conclusions Therefore, during the analysis period of 2000-2020 in South America, based on the panel data analysis under fixed effects, a total of 8 countries had a negative impact on trade openness, and only the economies of Chile, French Guiana, and Brazil had a positive impact on trade openness; these economies are characterized by their better performance in the economic complexity index, their higher percentage of budget for research and development expenses, and their trade policies oriented towards the industrialization of their value-added products.
Selfies, narcissism and oral health a cross - sectional study among adolescents and young adults in Mangaluru - India.
Authors: Prabhu Preeti , Pai Mithun , Yellapurkar Shweta , Natarajan Srikant , Mahuli Amit Vasant
Published: November 2024

Background Selfies have been defined as “a photograph that one has taken of oneself, and are a continuing growing trend among Millennials and Gen Z”. Narcissism refers to a personality trait of an extraordinary self-awareness and adoration. Studies have shown a close relationship between selfie-taking behavior, narcissism and oral health. Hence, a study was conducted with aim of assessing correlations between perceived health, perceived oral health, selfie-taking behavior, narcissism and oral health behavior in an adolescent population. Methods An analytical cross-sectional questionnaire study was designed using relevant literature for collating information on sociodemographic characteristics, frequency of dental visits, selfie-taking behavior and perceived oral health. Oral health examination was performed to assess decay and plaque using DMFT index and Plaque index. Narcissism was assessed using The Five-Factor Narcissism Inventory Short Form. Results The study included a sample of 163 participants. The associations between selfies taken per day and perceived oral health was statistically significant (p value 0.047*). Binary logistic regression models were constructed, which were significant for perceived oral health and grandiose fantasy. Plaque Scores showed significant corelations between indifference, manipulativeness, thrill seeking and age. Step forward binary regression demonstrated a significant odds ratio for grandiose narcissism followed by selfie-taking behavior Conclusion This study revealed a correlation between perceived oral health and selfie-taking behaviour. Further studies are required to assess selfie-taking behaviour and oral health.
A Bioconductor/R Workflow for the Detection and Visualization of Differential Chromatin Loops
Authors: Flores JP , Davis Eric , Kramer Nicole , Love Michael I , Phanstiel Douglas H
Published: November 2024

Background Chromatin loops play a critical role in gene regulation by connecting regulatory loci and gene promoters. The identification of changes in chromatin looping between cell types or biological conditions is an important task for understanding gene regulation; however, the manipulation, statistical analysis, and visualization of data sets describing 3D chromatin structure is challenging due to the large and complex nature of the relevant data sets. Methods Here, we describe a workflow for identifying and visualizing differential chromatin loops from Hi-C data from two biological conditions using the ‘mariner’, ‘DESeq2’ and ‘plotgardener’ Bioconductor/R packages. The workflow assumes that Hi-C data has been processed into ‘.hic’ or ‘.cool’ files and that loops have been identified using an existing loop-calling algorithm. Results First, the ‘mariner’ package is used to merge redundant loop calls and extract interaction frequency counts. Next, ‘DESeq2’ is used to identify loops that exhibit differential contact frequencies between conditions. Finally, ‘plotgardener’ is used to visualize differential loops. Conclusion Chromatin interaction data is an important modality for understanding the mechanisms of transcriptional regulation. The workflow presented here outlines the use of ‘mariner’ as a tool to manipulate, extract, and aggregate chromatin interaction data, ‘DESeq2’ to perform differential analysis of these data across conditions, samples, and replicates, and ‘plotgardener’ to explore and visualize the results.
The influence of dental fluorosis on shear bond strength: a systematic review protocol
Authors: Kallala Rim , Gassara Yosra , Dhraief Yasmine , Touzi Soumaya , Harzallah Belhassen
Published: November 2024

Dental fluorosis, a condition characterized by enamel hypoplasia caused by excessive fluoride intake, can potentially affect the adhesion of dental materials. This systematic review aimed to assess the influence of dental fluorosis on shear bond strength (SBS) and to provide clinical recommendations. A comprehensive search of electronic databases was conducted, followed by a rigorous selection process to include relevant in vitro studies. The quality of the included studies was assessed and data were extracted for analysis. Based on these findings, it is recommended to consider alternative bonding techniques or to use specific dental materials for fluorosis-affected teeth. Further research is needed to elucidate the mechanisms underlying the potential impact of dental fluorosis on shear bond strength and develop more targeted clinical strategies.
A Validated Trigonelline-Based Method for the Standardization and Quality Control of Trigonella foenum-graecum L.
Authors: Aldholmi Mohammed , Ahmad Rizwan , Hago Salma , Alabduallah Ali
Published: November 2024

Background Fenugreek, or Trigonella foenum-graecum L, is an edible and medicinal plant of the Fabaceae family. Fenugreek seeds contain a variety of phytochemicals, including proteins, lipids, amino acids, vitamins, flavonoids, steroidal saponins, coumarin, and alkaloids. Trigonelline TG is a bioactive plant alkaloid initially extracted from fenugreek seeds. A substantial portion of fenugreek’s health benefits may rely on the presence of TG. This study addresses the research gap for a fast, green, and economical method for quantifying trigonelline (TG) in fenugreek. Methods Fenugreek seeds from various origins were extracted using three green solvents: acetone (ACt), ethanol (EtOH), and water (H2O). The UPLCMSMS method was developed and validated using a green mobile phase of H2O: EtOH, and an r2-value of 0.999 in the linearity range of 0.1-500 ppb was adopted. The method was validated with an accuracy of 98.6% for trace analysis of TG using a small amount (10 mg) of fenugreek samples from five different origins. Results The average extract yield (±SD) was 5.36±6.3, with the highest extract yield observed in H2O. The ESI (+ve) of the UPLCMSMS resulted in the fragmentation pattern (m/z) 138→94.10→92.05→78.20. The TG quantification revealed an average TG concentration of 181.4, with the highest amount of TG in H2O extract (392.7±132.4 ppb), followed by EtOH (91.9±83.3 ppb) and ACt (59.5±30.9 ppb). The TG amount observed in the validation step substantiated the efficiency and reproducibility of the developed method. Conclusions The method may be used as an effective tool for a green, rapid, economical, and eco-friendly extraction and quantification of TG in diverse matrices of pharmaceutical, cosmeceutical, herbal, and food products.
Ethiopia's Potato Seed System: Regulatory Challenges, Quality Assurance Issues, and Pathways for Improvement ─ A mini review
Authors: Tessema Lemma , Seid Ebrahim
Published: November 2024

Background Ethiopia’s potato seed system is currently hindered by a disjointed regulatory framework, insufficient quality assurance processes, and a lack of collaboration among stakeholders, which collectively impede agricultural productivity and food security. The regulatory environment is characterized by inconsistent seed certification practices and a dependence on informal seed sources, negatively affecting the quality of potato seeds available to farmers. Although potatoes play a crucial role in global food security by providing high yields compared to other staple crops, the sector grapples with significant challenges due to bureaucratic inefficiencies, limited technical expertise, and the widespread presence of counterfeit seeds throughout the value chain. Methods To tackle these challenges, this mini-review outlines potential improvements, stressing the necessity for a unified regulatory framework tailored to the unique issues of vegetatively propagated crops. For this reason, we have used different literature source from web of science, Pubmed, Google Scholar, ResearchGate and other scientific websites. We have documented the most relevant information focusing on potato seed system, regulatory frameworks, quality assurance bottlenecks and pathways for improvement across the seed value chain. Results our paper highlights key recommendations that includes enhancing training for regulatory staff, investing in research for disease-resistant varieties, and bolstering public-private partnerships to encourage innovation and resource sharing. Furthermore, improving traceability in the seed supply chain is essential for maintaining seed quality and integrity. Conclusions This review calls for a comprehensive strategy that fosters stakeholder engagement and promotes sustainable practices to rejuvenate Ethiopia’s potato seed system, thereby supporting the livelihoods of millions of smallholder farmers and strengthening national food security through integrated seed sector development and capacity improvement of the seed regulatory body as well as smallholder farmers.
Knowledge and uptake of contraceptive and other sexual reproductive health services among in-school adolescents in three South African townships: Baseline findings from the Girls Achieve Power (GAP Year) Trial
Authors: Pleaner Melanie , Kutywayo Alison , Beksinska Mags , Mabetha Khuthala , Naidoo Nicolette , Mullick Saiqa
Published: November 2024

Background South African adolescents experience barriers to sexual and reproductive health (SRH) knowledge and uptake. This study provides insight into contraceptive and other SRH service knowledge, perceptions, and uptake among adolescents in high HIV prevalence settings. Methods A baseline cross sectional survey was conducted among 3432 grade 8s enrolled into the Girls Achieve Power (GAP Year) trial from 26 public high schools across three South African townships (Soweto, Thembisa and Khayelitsha) (2017 - 2018). An interviewer-led survey collected information on SRH knowledge and perceptions; an audio computer-assisted self-interviewing technique gathered SRH service uptake. Descriptive analysis indicates frequency distribution of socio-demographics and knowledge, uptake and perceptions of SRH services. Chi-square test tested for associations between age and sex and selected variables that measure SRH knowledge and uptake. Results In total, 2383 participants completed both survey components. Of these, 63.1% (n=1504) were female and 81.4% (n=1938) aged 12-14. Almost a fifth (18.3%, n=436) had ever had sex and less than 1% had accessed SRH services in the last year. Of the 157 females who had ever had sex, 50.9% had ever used contraception. Of those who had sex in the last three months, 59.0% reported using a contraceptive method. Condom use was inconsistent: almost all females said they had not used or could not remember if a condom was used at last sex. Conclusion This paper contributes to the evidence strengthening learner SRH education, including the national Integrated School Health Programme. Key themes include the need for age-appropriate, differentiated comprehensive sexuality education (CSE) for the range of ages found in the same grade in South African schools. Education on different contraceptive methods, informed decision-making, and emergency contraception is key. School-based interventions should embrace integrated HIV, STI, and pregnancy prevention messages. Closer links with health services need to be constantly fostered and reinforced.
Impact of Green Tea Consumption and Its Extracts on Fat Reduction and Weight Loss
Authors: Ptak Anita , Szyc Michał
Published: November 2024

Introduction: Obesity and overweight are major health problems and challenges in the world today. It is the task of modern pharmacology, medicine and dietetics to search for new therapeutic methods to reduce body weight and body fat. Green tea has been a focus of research on its effects on weight reduction for many years. This article will analyse the available studies on the effectiveness of green tea on body weight and body fat reduction in obese and overweight people. Aim of the study: The aim of this review is to analyse the available literature in order to answer the question of whether green tea and green tea extracts (GTE) have an effect on weight loss, body fat reduction and associated metabolic processes.Materials and method: For a comprehensive review on the effects of green tea on weight and body fat reduction, we reviewed studies and literature available in databases such as PubMed and Google Scholar by searching through keywords such as ‘green tea’, ‘obesity’, ‘fat’, ‘weight loss’, ‘matcha’.Conclusion: green tea and its isolated substances such as epigallocatechin-3-O-gallate (EGCG) appear to have a positive effect on weight and body fat reduction in obese and overweight individuals. It is likely that consumption of green tea extract increases fat oxidation during exercise. In addition, supplementation had a positive effect in a group of diabetics, polycystic ovary syndrome and metabolically stressed patients. The best effects from supplementation were obtained by those who additionally had physical activity. It is suggested that research on green tea, especially on matcha, should continue, as very little reliable research has been produced on this topic
Heterogeneous Complementarity and Team Design: The Case of Real Estate Agents
Authors: Xu Yan , Hu Mantian , Chu Junhong , Ching Andrew T.
Published: November 2024

Heterogeneous complementarity between workers with different (unobserved) characteristics significantly impacts teamwork and the design of effective teams.
Rheumatoid arthritis: a rare cause of pachymeningitis and optic neuritis
Authors: Gondal Muhammad Umer Riaz , Graves Josette , Khan Haider , Baig Mohammad , Khan Toqeer , Khalid Fatima , Pagolu Pavani
Published: November 2024

Introduction: Rheumatoid pachymeningitis and optic neuritis are rare complications of rheumatoid arthritis (RA) and are a diagnosis of exclusion. Case description: A 75-year-old male with a history of seronegative RA presented to the emergency department with left eye pain and blurry vision lasting two days. He had been diagnosed with seronegative RA around nine months previously. His blood pressure was elevated at 204/75 mmHg upon arrival. Physical examination revealed left conjunctival injection, mild ptosis, painful extraocular movements and tenderness over the orbit and sinuses. Initial treatments included painkillers and intravenous labetalol, which alleviated his symptoms and decreased his blood pressure. Laboratory tests showed a C-reactive protein of 2.5 mg/dl and an erythrocyte sedimentation rate of 32 mm/h, with other blood work unremarkable. A computed tomography (CT) angiogram of the head and neck showed no high-grade stenosis. Given his RA history, initial concerns included scleritis. A magnetic resonance imaging (MRI) of the brain and orbit revealed inflammation around the left optic nerve, and pachymeningitis at the left cerebral convexity and interhemispheric fissure, suggesting hypertrophic pachymeningitis. An ophthalmologic examination was unremarkable. Treatment was adjusted to include pulse doses of intravenous methylprednisolone for optic neuritis, resulting in significant pain relief. Though inadequate for complete testing, a lumbar puncture indicated an inflammatory disorder with elevated glucose (199 mg/dl), protein (109 mg/dl), and unremarkable WBC/RBC and Gram staining. Cytology and culture were unremarkable. The most likely diagnosis at this point was rheumatological meningitis and rheumatological optic neuritis. The patient improved markedly with high-dose steroids over four days and was discharged on prednisone. Conclusion: In cases of optic neuritis and pachymeningitis, RA should remain on the differential in patients with or without a prior diagnosis.
Can you diagnose immune thrombocytopenia in myeloma? A case of thrombocytopenia in a patient with multiple myeloma
Authors: Diogo Cláudia , Fernandes Carolina , Cunha Sandra , Luz Luís , Santos João Gaião , Monteiro Joana Raquel
Published: November 2024

Multiple myeloma (MM) is the second most common haematological malignancy, the diagnosis of which has doubled in recent years. Immune thrombocytopenia consists of isolated thrombocytopenia secondary to antibody mediated peripheral platelet destruction. In most cases, there is no identifiable cause (primary immune thrombocytopenia). Its association with multiple myeloma is rare. Early recognition of this association is essential for raising awareness among clinicians, allowing for a rapid differential diagnosis and therapeutic optimization, reducing side effects and improving prognosis. Thus, we present a clinical case of concomitant immune thrombocytopenia and MM, whose initial presentation was thrombocytopenia. This clinical case is the first case among thirteen described in the literature in which chemotherapy was the initial treatment for both pathologies, as seen in this review.
Interventional Pain Management in Degenerative Spine Disorders: A Case Report
Authors: Hutagalung Muhammad Bayu Zohari
Published: November 2024

Low back pain (LBP) is a common health issue affecting a significant portion of the population, particularly adults aged 35-55 years. Nearly 70-80% of individuals in developed countries experience LBP at some point in their lives. We reported a 54-year-old female presenting with LBP persisting for one year. Her pain predominantly occurs during walking, is limited to 100 meters, and is characterized by gripping sensations in the thigh and calf, exacerbated by positional changes but relieved with rest. Imaging revealed anterior listhesis of the L4 vertebral body relative to L5 (<25%) and multiple bulging discs at various lumbar levels, most notably severe at L4-5 with moderate central and severe bilateral neural foraminal stenosis. The patient underwent Selective Nerve Root Block (SNRB) and facet joint blocks with local anesthetic and steroid medication, resulting in a reduction of pain complaints and decreased leg numbness post-intervention. Understanding and addressing specific spinal pathologies in this case was expected to guide effective treatment strategies to alleviate symptoms and improve patient function.
Integrating services
Authors: McClean Andrew
Published: November 2024

Andrew McClean explores the benefits of introducing audiology services in-house or via a third party
NHS delays causing sight loss
Authors: McClean Andrew
Published: November 2024

Andrew McClean finds out about the AOP's new national eye health campaign
Going green: How Coopervision is leading the way in transforming contact lens wear into a sustainable choice
Authors: Walsh Karen , Riggs Paul
Published: November 2024

Optometrist and Global Professional Affairs Director Karen Walsh and Paul Riggs, Science and Sustainability Director, CooperVision, take a look at the rising demand for sustainable products and how CooperVision is leading the industry with an innovative model for sustainability designed to reduce the contact lens manufacturer's environmental impact and meet this demand, now and in the future
Seeing clearly
Authors: Gudwin Ella
Published: November 2024

Ella Gudwin outlines the benefits of better global eye health and calls for eye care professionals to get involved
Presbyond
Authors: Jones Nabila , Sisó-Fuertes Irene , Hamid Amir , O'Donnell Clare
Published: November 2024

Dr Nabila Jones, Dr Irene Sisó-Fuertes, Mr Amir Hamid and Dr Clare O'Donnell present a case study showing the patient journey and expected outcomes with the laser blended vision, or Presbyond, technique
Full of beans
Authors: White Emma
Published: November 2024

Emma White talks to Austrian eyewear brand Rolf Spectacles about the company's award-winning kids’ collection, new limited-edition frames and its commitment to creating honest and sustainable eyewear
Controlling the cataract flow
Authors: Harvey Bill
Published: November 2024

Bill Harvey learns much from a recent online webinar, hosted by Thea Pharmaceuticals, which looked at measures being adopted to address the backlog of cataract operations since the pandemic
Challenging headwinds
Authors: Jones Simon
Published: November 2024

Record sales for Inspecs but instability in Europe hurts the bottom line. Simon Jones reports
Styles by Safilo
Authors: McCarthy-McClean Andrew
Published: November 2024

Andrew McCarthy-McClean previews autumn/winter 2023 collections from Safilo's licensed brands
Failing to learn from teachers: the Social Work Early Career Framework in England
Authors: Hanley Joe , Rowe Jan
Published: November 2024

This article presents a critical analysis of the Social Worker Early Career Framework in England, planned for national roll-out in September 2026 to replace the Assessed and Supported Year in Employment for children and family social workers. The Social Worker Early Career Framework is based on the existing Teacher Early Career Framework in England, launched nationally in 2021. The article argues that both the problematic experience of its counterpart in teaching and the existing evidence around similar initiatives already implemented in social work suggest that the Social Worker Early Career Framework is highly unlikely to achieve its stated aims. These discussions are followed by a consideration of why the Social Worker Early Career Framework is being introduced despite this existing evidence. It is suggested that a relatively small, opaque and overlapping policy network dominating children’s services reform in England provides a possible explanation.
Design and FDTD simulation of a remote-controllable visible-light plasmonic waveguide and refractive-index-sensitive switch
Authors: Yang Peng , Jiao Jiasheng , Chen Yu , Ouyang Fangping
Published: November 2024

In this paper, a plasmonic switch based on metal-insulator-metal (MIM) waveguide structure is proposed, whose transmission characteristics can be remotely controlled by a rake switch design. The distance from the remote control unit to the bus waveguide is more than 1 um and still maintains a very high efficiency. The refractive-index-dependent transmission spectrum of this filter was simulated using the finite-difference time-domain method. The results show that the on/off switching of wave propagation in the bus waveguide can be achieved by changing the refractive index of the control unit 1 µm away from the bus waveguide. A change in refractive index of only 0.2 is required to simultaneously control the switching off and on of four waves in the waveguide in the visible band, with corresponding switching ratios of 40.5, 74.3, 48.6, and 15.1, showing great potential for applications in refractive index sensors and remotely controllable band stop filters.
Analytical Z-scan model for multiphoton absorption in inhomogeneous media
Authors: Kessi Ferhat
Published: November 2024

This work presents an analytical model for multiphoton absorption in inhomogeneous materials, developed within the framework of the Z-scan technique using the weak nonlinearity approximation. The model addresses arbitrary order n of multiphoton absorption processes and considers linear variations in material properties. Three cases are investigated: purely axial, purely radial, and combined axial and radial inhomogeneities in the absorption coefficient. Simulations reveal distinct normalized transmittance profiles for each case, demonstrating the significant impact of linearly varying inhomogeneities on multiphoton absorption. The purely axial case shows symmetric, broad dips in transmittance centered at the focal point, while the purely radial case exhibits narrower, more localized absorption profiles. The combined case demonstrates a synergistic effect, resulting in enhanced absorption.
Multiring polygon super-geometric beam generation based on the quasi-frequency- degeneracy state of a multiaxial super-geometric mode laser
Authors: Liu Lu , Wang Fuyong
Published: November 2024

Novel structured modes with a multiring polygon shape are anticipated in the quasi-frequency-degenerate (QFD) cavity, and their counterpart modes are multiaxial super-geometric (MASG) modes in the frequency-degenerate (FD) cavity. The multiring polygon super-geometric modes are numerically constructed by extending their decomposed multiaxial geometric (MAG) modes in the FD state to the modes in the QFD state, implying that they are a kind of special transverse mode in the QFD laser cavity. Then, the characteristics of the multiring polygon super-geometric modes are investigated under different parameters. Studying the multiring polygonal-shaped optical modes may broaden the application areas of structured light, such as particle trapping and manipulation.
Deep-red planar waveguide laser operation of Eu3+:KY(WO4)2 layers
Authors: Baillard Amandine , Bae Ji Eun , Ceballos Mailyn , Loiko Pavel , Solé Rosa Maria , Aguiló Magdalena , Díaz Francesc , Brasse Gurvan , Mateos Xavier , Camy Patrice
Published: November 2024

We report on the first deep-red europium planar waveguide laser. It employs 30-µm thick heavily-doped 11.5 at.% Eu:KY(WO4)2 layers grown by liquid phase epitaxy on undoped substrates using K2W2O7 as a solvent. When pumped with a green laser at 532 nm, the Eu-waveguide laser delivers a maximum output power of 7 mW at 704.7 nm with a slope efficiency of 9.5%, a laser threshold of 21 mW, and linear polarization. The waveguide propagation losses are as low as 0.05 dB/cm. The morphology, vibronic, and spectroscopic properties of the epitaxial layers are also studied. In the deep red, for the 5D0 → 7F4 transition, the stimulated-emission cross-section reaches 1.76 × 10−20 cm2 at 704.7 nm for light polarization
E
|| Np, and the luminescence lifetime of the 5D0 manifold is 472 µs.
Minimizing matrix effect in uranium polymetallic ores by orthogonal non-confocal femtosecond-nanosecond laser induced breakdown spectroscopy
Authors: Zhu Huihui , Dong Xuelin , Feng Lei , Zhang Yubo , Wu Zhuo , Lü Tao
Published: November 2024

To mitigate the negative impact of the matrix effect on the quantification in uranium polymetallic ores using laser induced breakdown spectroscopy (LIBS), we employed orthogonal non-confocal femtosecond-nanosecond (fs-ns) LIBS to minimize matrix effects. The fs pulse laser pre-ablates to form aerosol particles, which are subsequently broken down by the following ns pulse laser and emitted atomic spectra. The dynamic characteristics were recorded using the time-resolved pump-probe shadowgraph technique. The relative sensitivity factors (RSFs) of Dy, Th, Nb, and Y obtained by fs-ns LIBS are more stable, with correlation coefficients (r) of the fitted curves all above 0.977. For ns-LIBS, the values of r were 0.827, 0.63, 0.947, and 0.975, respectively. When the characteristic spectral line Th I 330.42 nm was selected to predict the Th concentration, for fs-ns LIBS and ns-LIBS, the regression coefficients (R2) were 0.91 and 0.47, and the relative errors were 8.14% and 22.02%, respectively. This confirms that fs-ns LIBS may effectively minimize matrix effects, improve the accuracy of elemental quantification, and even overcome the shortage of matrix-matched standard samples.
Research on target recognition of multispectral streak tube imaging lidar system using multimodal convolutional neural network
Authors: Li Wenhao , Zhai Yu , Li Longfei , Liu Kun , Shi Qihan , Wang Jin , Han Shaokun
Published: November 2024

A new multispectral streak tube imaging lidar is proposed to address the shortcomings of the traditional streak tube imaging lidar which can only provide single wavelength reflection information of the target. The accuracy of the depth map is improved by fusing the reconstructed depth images. To implement the target classification task, a dataset based on depth images and intensity images was first built, which consists of 240 targets with a total of 20 classes. Then, a multimodal neural network model was designed to classify the targets based on the characteristics of the dataset. The target classification ability of three methods which are depth images, depth images + intensity images and depth images + 3 intensity images are compared. The experimental results show that the proposed method can effectively improve the target recognition accuracy, which is increased from 85.19% to 90.47%.
Effects of dissipation rates on dispersive waves and mode families in microresonators with avoided mode-crossing
Authors: Jiao Chen , Xu Xin , Liu Xinyu , Ye Huichun , Jin Xueying , Chen Dong , Pan Chengliang , Xia Haojie
Published: November 2024

In microresonators with avoided mode-crossing, the dispersive waves and mode families can be affected by dissipation rates, which also cause different hysteresis of the dispersive waves. Based on the Lugiato-Lefever equations and the single-mode dispersive wave model, the effects of dissipation rates on dispersive waves and mode families in microresonators are investigated. Results showed that the dispersive wave power curve exhibits hysteresis because of the avoided mode-crossing and the frequency shift curves can be convex, contrary to the absence of hysteresis. Moreover, the distribution of the two mode families in the microresonator is different at various detuning frequencies due to the dispersive wave, and it is relatively flat in the hysteresis state. The dispersive wave power and frequency shift are varied due to the different dissipation rates. The power of the two mode families decreases with the increase in mode dissipations. The results are significant for investigating dissipative Kerr solitons associated with dispersive waves in microresonators with avoided mode-crossing in practice.
Sensitivity enhancement of time-gated Raman spectroscopy by reducing the systematic noise of residual fluorescence background
Authors: Wang Zhenyou , Fang Guangyou
Published: November 2024

Fluorescence interference is a pervasive challenge in Raman spectroscopy, often limiting its broader application. Time-gated Raman spectroscopy offers a more universal solution by temporally separating Raman signals from fluorescence; however, it faces significant challenges when dealing with samples that exhibit short fluorescence lifetimes. Achieving high time resolution to effectively distinguish these signals typically requires advanced detectors that are not only costly but also difficult to source commercially, often resulting in substantial residual fluorescence that diminishes overall signal quality. In this work, we identified that the dominant noise in time-gated Raman spectroscopy is wavelength-to-wavelength fluctuation noise, which cannot be reduced by simply extending the collection time. Through our analysis, we discovered that this noise is linearly proportional to the fluorescence background and remains consistent across different time windows when collected using the time-correlated single-photon counting (TCSPC) technology. Recognizing this consistent pattern, we developed a novel, to the best of our knowledge, method to effectively remove this noise by leveraging the time-resolved fluorescence spectrum. For example, in the case of sesame oil excited with a 532 nm laser, it is typically difficult to obtain a recognizable Raman spectrum when the gate width exceeds 300 ps. However, using our method, we were able to achieve a decent signal even with a gate width of 4 ns. By correcting the Raman spectrum using the captured pure fluorescence spectrum, we achieve up to a 23-fold improvement in the signal-to-noise ratio (SNR). This innovation significantly reduces the dependence on high-cost, high-time-resolution detectors, potentially expanding the adoption and applicability of time-gated Raman spectroscopy across various fields.
High-fidelity digital–analog hybrid RoF fronthaul link enabled by nonlinear radio signal shaping
Authors: Cheng Chen , Yang Bang , Tang Jianwei , Hao Yaguang , Xu Zhaopeng , Liang Junpeng , Wu Qi , Gong Siyu , Fan Linsheng , Xiang Qian , Zhang Qun , Li Xueyang , Yao Yong , Wei Jinlong , Yang Yanfu
Published: November 2024

We propose a simple and effective method to enhance the fidelity of radio signals in a digital-analog radio-over-fiber (DA-RoF) system by introducing nonlinearity into the transmitted signal. This nonlinearity is introduced via an arctangent function for radio signal shaping (RSS), while the corresponding tangent function is used for signal recovery. Nonlinear shaping spreads near-zero amplitude signals and compresses far-from-zero ones. After nonlinear recovery, noise in near-zero signals is suppressed, while noise in far-from-zero signals is amplified. Since the radio signal follows a Gaussian distribution, with most amplitudes near zero, the overall SNR is improved. In our experiments, we demonstrate the proposed radio signal shaping technology using a DA-RoF system based on intensity modulation with a direct detection communication system, achieving a 1.8-dB SNR gain. We achieve an SNR of 34.17 dB for QAM-1024 signals at a DA-RoF symbol rate of 104 Gbaud over 1 km of fiber. This corresponds to a CPRI-equivalent rate of 1560 Gbps and an equivalent fronthaul channel capacity of 294.85 Gbps. Our proposed scheme offers a promising solution for high-fidelity, high-capacity RoF links in Beyond 5G (B5G) and 6G networks.
Optimization of fs-laser-induced voxels in nonlinear materials via over-correction of spherical aberration
Authors: Lapointe Jerome , Pouliot Samuel , Dupont Albert , Guérineau Théo , Gaulin Joseph , Pelletier Étienne , Delarosbil Jean-Luc , Lafrenière-Greig Jonathan , Olivier Loïc , Gagnon Stéphane , Messaddeq Younes , Vallée Réal
Published: November 2024

In this Letter, over-correction of spherical aberration is used to counteract nonlinear effects such as Kerr self-focusing and plasma effects, resulting in more spherical and small-sized femtosecond laser-inscribed voxels within nonlinear materials. By strategically redirecting marginal focusing rays toward the beginning of the laser modification zone, the induced plasma prevents any rays from causing a structural modification beyond this zone, irrespective of any focus elongation caused by nonlinear effects. The method has been effectively validated across a range of materials, including ZnS, ZnSe, BIG, GeS4, and SiO2. A significant outcome is the achievement of quasi-spherical and (sub-)micrometer voxels in highly nonlinear materials. These findings open avenues for single-mode active waveguides and high-resolution patterning within nonlinear materials. The experiments are performed using a microscope objective equipped with a correction collar, a widely available tool in laboratories, highlighting the potential and versatility of the technique.
Bound state of asymmetric pure-quartic solitons in motion
Authors: Zhang Chunxiang , Deng Zhixiang , Ma Rui , Lu Haiyang , Fan Dianyuan , Liu Jun
Published: November 2024

In this Letter, we investigate the binding mechanism and motion dynamics of the bound state consisting of two pure-quartic solitons (PQSs) with unequal intensities and find that their movement occurs as an entity under the Raman self-frequency shift. By calculating the forces that induce the relative motion between the unequal PQSs, we derive the balanced conditions for maintaining a near-constant separation and the constant phase profile between them. The predictions are validated by the numerical simulations. Our work provides insights into the intrinsic features of symmetry-broken localized structures in nonlinear–dispersive systems, stimulating interest in asymmetric multi-soliton states with intriguing dynamics.
High-specificity SERS sensing with magnet-powered hierarchically structured micromotors
Authors: Fan Xingce , Zhao Xing , Tang Xiao , Li Guoqun , Wei Yunjia , Chen Dexiang , Kong Fan , Lan Leilei , Wang Jiawei , Hao Qi , Qiu Teng
Published: November 2024

This work reports a hierarchically structured micromotor (HSM) surface-enhanced Raman scattering (SERS) platform comprising 3D tubular configurations with nanostructured outer walls. The HSMs can be powered by an external magnetic field in solution to enrich molecules with promoted adsorption efficiency. The nanostructured outer wall serves as containers to collect molecules and produce strong localized surface plasmon resonance to intensify Raman of the enriched molecules. Further coupling of HSMs after molecular enrichment can produce additional plasmonic hotspots at the sites where the molecules were enriched, providing a solution to manipulate molecules to enter the plasmonic hotspot region. Moreover, functionalizing specific molecules on the outer wall of HSMs enables high-specificity SERS sensing for benzaldehyde (BA) and Cu2+ ions in liquid. This SERS platform demonstrates great potential for practical applications in biochemical analysis and environmental monitoring, offering a rapid and sensitive tool for detecting low-concentration analytes in liquid.
Dissipation-induced nonreciprocal magnon entanglement and one-way steering in waveguide electromagnonics
Authors: Lü Rongguang , Zhan Huiping , Kong Deyi , Wang Fei
Published: November 2024

We propose a scheme to generate nonreciprocal entanglement and one-way steering between two distant ferrimagnetic microspheres in waveguide electromagnonics, where the magnon modes of two yttrium iron garnet (YIG) spheres are simultaneously coupled to each other through coherent and dissipative interactions. By matching the coherent interaction with its corresponding dissipative counterpart, unidirectional coupling between two magnon modes can be realized, and then in the presence of significant Kerr nonlinearities, we can obtain strong entanglement and one-way steering. Depending on the direction of the microwave propagation, the long-distance entanglement and steering can be generated nonreciprocally. Our work presents a novel, to the best of our knowledge, approach for generating nonreciprocal quantum correlations, which may find potential applications in chiral quantum networking.
Structured illumination microscopy based on Kramers–Kronig relations for quantitative phase reconstruction
Authors: Wang Yiran , Li Yutong , Li Ziyang , Zhou Xuyang , Ji Yu , Liu Gangshan , Zhao Pengtao , Yang Shurui , Liu Zhengjun , Liu Shutian
Published: November 2024

Structured illumination microscopy (SIM) is a widely applied fluorescence super-resolution imaging technique. It can also serve as high-throughput imaging in coherent imaging systems. However, coherent SIM requires additional qualitative/quantitative phase imaging methods to acquire phase information. This paper proposes a structured illumination microscopy technique based on the Kramers–Kronig relations (KK-SIM) that achieves quantitative phase imaging without the need for extra technical assistance and relies solely on the spatial-domain intensity images reconstructed through conventional SIM. KK-SIM utilizes a non-iterative approach to recover intensity into amplitude and phase, maintaining SIM’s high acquisition speed and reconstruction efficiency. Our work enables high-throughput quantitative phase imaging using conventional SIM experimental setups and data post-processing, making SIM suitable for label-free, noninvasive dynamic observation.
Parallel generation of multi-channel broadband chaos by a long-cavity FP laser with optical feedback
Authors: Li Qingtian , Jia Zhiwei , Wang Anbang , Wang Yuncai
Published: November 2024

Parallel generation of multi-channel chaos is critical to applications, and the key challenge is the simultaneous generation of broadband chaos with multiple channels and low correlation. Here, we experimentally demonstrate a parallel broadband chaos generation scheme using a single long-active-cavity Fabry–Perot (LC-FP) semiconductor laser under optical feedback. The active-cavity length is designed to be 1500 μm, so the power spectrum of chaos is expanded and flattened by the mode-beating effect. The experimental result shows that all-mode chaos with a bandwidth of 33.76 GHz and a spectrum flatness of ±2.5 dB is obtained. Furthermore, eight-channel chaotic signals with bandwidth larger than 27 GHz and correlation coefficients smaller than 0.1 are parallelly generated using optical filtering, where the spectrum flatness is about ±4 dB.
Exploring photon-number-encoded high-dimensional entanglement from a sequentially excited quantum three-level system
Authors: Vajner Daniel A. , Kewitz Nils D. , von Helversen Martin , Wein Stephen C. , Karli Yusuf , Kappe Florian , Remesh Vikas , Covre da Silva Saimon F. , Rastelli Armando , Weihs Gregor , Anton-Solanas Carlos , Heindel Tobias
Published: November 2024

The sequential resonant excitation of a two-level quantum system
results in the emission of a state of light showing time-entanglement
encoded in the photon-number basis: notions that can be extended to
three-level quantum systems as discussed in a recent proposal
[ Opt.
Lett. 48, 6332
(2023)10.1364/OL.506403 ]. Here, we report the
experimental implementation of a sequential two-photon resonant
excitation process of a solid-state three-level system, constituted by
the biexciton, exciton, and ground states of a semiconductor quantum
dot. The resulting light state exhibits entanglement in time and
energy, encoded in the photon-number basis, which could be used in
quantum information applications, e.g., dense information encoding or
quantum communication protocols. By performing energy- and
time-resolved correlation experiments in combination with extensive
theoretical modeling, we are able to partially retrieve the
entanglement structure of the generated state and extract an upper
bound for the fidelity to the entangled target state of F≤70% before loss.