bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra-high-capacity band and space division multiplexing backbone EONs: multi-core versus multi-fiber
Authors: Arpanaei Farhad , Zefreh Mahdi Ranjbar , Natalino Carlos , Lechowicz Piotr , Yan Shuangyi , Rivas-Moscoso José M. , González de Dios Óscar , Fernández-Palacios Juan Pedro , Rabbani Hami , Brandt-Pearce Maite , Sánchez-Macián Alfonso , Hernández José Alberto , Larrabeiti David , Monti Paolo
Published: October 2024

Both multi-band and space division multiplexing (SDM) independently represent cost-effective approaches for next-generation optical backbone networks, particularly as data exchange between core data centers reaches the petabit-per-second scale. This paper focuses on different strategies for implementing band and SDM elastic optical network (BSDM EON) technology and analyzes the total network capacity of three sizes of backbone metro-core networks: ultra-long-, long-, and medium-distance networks related to the United States, Japan, and Spain, respectively. Two BSDM strategies are considered, namely, multi-core fibers (MCFs) and BSDM based on standard single-mode fiber (SSMF) bundles of multi-fiber pairs (BuMFPs). For MCF-based BSDM, we evaluated the performance of four manufactured trench-assisted weakly coupled (TAWC) MCFs with 4, 7, 13, and 19 cores. Simulation results reveal that, in the regime of ultra-low (UL) loss and inter-core crosstalk (ICXT), MCF-based throughput can be up to 14% higher than SSMF BuMFP-based BSDM when the core pitch exceeds 43 µm and the loss coefficient is lower than that of standard single-mode fibers. However, increasing the number of cores with (non-)standard cladding diameters, UL loss, and ICXT coefficient is not beneficial. As core counts increase up to 13 for non-standard cladding diameters (<230µm), the core pitch and loss coefficient also increase, leading to degraded performance of MCF-based BSDM compared to SSMF BuMFP-based BSDM. The results indicate that, in scenarios with 19 MFPs, SSFM BuMFP-based BSDM outperforms 19-core MCF-based scenarios, increasing the throughput by 55% to 73%, from medium-backbone networks to ultra-long ones.
Automation of multi-layer multi-domain transport networks and the role of AI [Invited]
Authors: González de Dios Óscar , Armingol Robles Pablo , Roelens Liesbeth , Muñiz-Da-Costa Alejandro , de Miguel Ignacio , Durán Barroso Ramón J. , Fernández-Palacios Juan Pedro
Published: October 2024

With increasing demand for customized connectivity, transport networks must evolve towards autonomous and customer-driven network management. This paper presents a comprehensive overview of network autonomy and the challenges associated with evolving toward higher levels of autonomy. Moreover, various use cases of artificial intelligence in network automation in IP-over-DWDM transport networks are also analyzed, in particular related to traffic prediction, quality of transmission, anomaly detection, network planning, and proactive failure management. Additionally, the role of generative AI in network operation is explored. Central to our discussion is a proposed control architecture based on open and standard SDN APIs, which incorporates network slicing for multi-layer transport networks and enables real-time access to normalized data, facilitating autonomous network operation.
Quadri-wave lateral shearing interferometry: a versatile tool for quantitative phase imaging
Authors: Xie Jun , Xie Hui , Kong Cheng Zhen , Ling Tong
Published: October 2024

Quantitative phase imaging (QPI) has emerged as a powerful tool in label-free bioimaging, in situ microstructure characterization for advanced manufacturing, and high-speed imaging of material property changes. Among various QPI methods, quadri-wave lateral shearing interferometry (QWLSI) stands out for its unique advantages in compactness, robustness, and high temporal resolution, making it an ideal choice for a wide range of applications. The compact design of QWLSI allows for easy integration with existing microscopy systems, while its robustness is manifested in the ability to maintain precise interferometric sensitivity even in high-vibration environments. Moreover, QWLSI also enables single-shot measurements that facilitate the capture of fast dynamic processes. This paper provides an in-depth exploration of the technical aspects of QWLSI, focusing on the evolution of its optical system and the primary algorithms used in wavefront reconstruction. The review also showcases significant applications of QWLSI, with a particular emphasis on its contributions to biomedical imaging. By discussing the advantages, limitations, and potential future developments of QWLSI, this paper aims to provide a comprehensive overview of this powerful QPI technique and its impact on various research fields.
Addressing high-performance data sparsity in metasurface inverse design using multi-objective optimization and diffusion probabilistic models
Authors: Zhang Zezhou , Yang Chuanchuan , Qin Yifeng , Zheng Zhihai , Feng Jiqiang , Li Hongbin
Published: October 2024

Recent advancements in deep learning, particularly generative networks capable of producing high-freedom structures, have significantly enhanced the precise generation of meta-atoms. However, these methodologies typically rely on an abundance of high-performance data, which remains scarce in many practical design scenarios. To bridge this gap, our study introduces what we believe to be a novel approach that synergistically combines multi-objective optimization algorithms with an enhanced diffusion model featuring an attention mechanism, termed MetaDiffusion-Att. Using the complex design task of dual-polarized, wide-angle incidence, and broadband low-emissivity electromagnetic glass as an application example, we demonstrate the effectiveness of our method through qualitative and quantitative experiments. The introduced multi-objective optimization method significantly captures more high-performance samples while ensuring high degrees of freedom, compared to currently widely used generic dataset construction methods. The MetaDiffusion-Att model, improved by the introduced attention mechanism, significantly outperforms conventional WGAN-GP and conditional VAE methods in generation accuracy and quality under small datasets. Furthermore, the proposed method exhibits extrapolation capabilities, generating new structures with performance surpassing that of the dataset, further enriching the design space. This framework provides a promising solution for the inverse design of metasurfaces in challenging scenarios with sparse high-performance samples.
Single-photon 3D imaging of room-scale scenes through scattering media
Authors: Zeng Jianwei , Li Wei , Zhou Yijun , Xu Feihu
Published: October 2024

Light detection and ranging (LiDAR) utilizes eye-safe laser beams to perceive the world in three-dimensional (3D) detail, offering machines and computers with an accurate representation of their surroundings. This technology is widely employed in metrology, environmental monitoring, archaeology, and robotics. However, the presence of scattering media in the optical path, such as fog, dust, or translucent plates, will cause light scattering and occlude direct observation of the scene. To address scattering distortions, conventional methods require the prior knowledge of the scattering media or the target location, limiting their applicability outside the laboratory. Leveraging single-photon sensitivity and time-gated technology, single photon LiDAR emerges as a promising solution for active scattering imaging. In this study, we construct a single-photon LiDAR prototype and demonstrate its capability to perform 3D imaging of a room-scale (1.1 m × 1.1 m × 4 m) hidden scene behind a ground glass diffuser located approximately 50 meters away from the imaging system. Incorporating phase function to construct the forward model and considering the system-induced temporal broadening, our method is capable of producing reliable results behind various scattering layers. The results indicate potential applications such as remote non-invasive testing and detection in challenging scenarios.
Phase-transition metamaterial smart window for radiative cooling and privacy protection
Authors: Wu Linsong , Chen Shujing , Lin Chengyou
Published: October 2024

This paper proposes a smart window for radiative cooling with adjustable transparency by leveraging the phase transition property of VO2. The proposed smart window exhibits daytime visible light transmission and near-infrared light reflection, all-day radiative cooling, and a nighttime privacy protection feature. It comprises a bottom layer of VO2/Ag/VO2 and top cubic two-dimensional SiO2 gratings, with structural parameters optimized by the genetic algorithm to ensure excellent optical performance. In the daytime, 75.4% visible light transmittance and 87.8% near-infrared reflectance can be achieved by utilizing the dielectric state of VO2. It also achieves low light transmission of 9.8% by using the metallic state of VO2, which is suitable for nighttime privacy protection. Furthermore, it has an all-day outside emissivity of 98.2% for radiative cooling, together with a low inside emissivity of 1.9% for effectively inhibiting the radiation heat transfer. In addition, the proposed structure is insensitive to the angles of incidence and the polarization of light, making it advantageous for radiative cooling. During the daytime, it reduces the temperature by 17.7 K compared to a glass of equal thickness when the non-radiative heat coefficient is 12 W/m2/K. At night, it achieves a cooling power of 124.7 W/m2, achieving a cooling effect of 8.9 K below ambient temperature. The proposed smart window is promising for various application scenarios for radiative cooling and privacy protection and could be used as windows for buildings and vehicles.
Chiral sensing via dielectric waveguide-nanoparticle array interactions
Authors: Nouri Hamed , Nader Askarpour Amir , Dehkhoda Parisa , Tavakoli Ahad
Published: October 2024

Identifying the handedness of chiral materials in small quantities remains a significant challenge in biochemistry. Nanophotonic structures offer a promising solution by enhancing weak chiroptical responses through increased optical chirality. Utilizing a silicon-based approach for chiral sensing on a photonic integrated platform is highly desirable. In this study, we explore the interaction between a dielectric waveguide and silicon nanoparticles for detecting the handedness of chiral analytes. A chiral core induces polarization rotation of wavefields traveling along a dielectric waveguide with a square cross-section. This polarization rotation affects waveguide coupling differently depending on the left- or right-handed arrangement of nanoparticles around the waveguide, enabling enantiomer detection through discernible transmission differences. From a basic design to more practical structures, we investigate configurations that maintain the same working principles. Theoretical results based on the transfer matrix method corroborate the numerical simulations.
Performance evaluation of a two-stage few-mode EDFA for high-capacity SDM systems
Authors: Lozada Astrid , Olivares Ricardo , Jara Nicolás , Morales Patricia , Feris Bárbara Dumas , Leiva Ariel , Saavedra Gabriel , Bórquez-Paredes Danilo
Published: October 2024

Space division multiplexing (SDM) systems using few-mode fibers (FMF) are essential for next-generation fiber optic communications. Optical amplifiers with low noise, minimal differential modal gain (DMG), and minimal differential spectral gain (DSG) are essential for these systems. In this work, we present a method to design and optimize a two-stage few-mode erbium-doped fiber amplifier (FM-EDFA) using a joint DMG-DSG minimization approach. This methodology involves the pumping profile design and the gain flattening filter design. Simulation results show the two-stage FM-EDFA achieves DMG and DSG below 2.8 dB and 0.42 dB, respectively, with an optical signal-to-noise ratio above 19 dB across the C-band, enabling a system capacity of 48.6 Tbps. This work reveals the effectiveness of this two-stage FM-EDFA for optical amplification in the context of SDM systems.
Adaptive generation of optical single-sideband signal with dually modulated EML
Authors: Zhao Shuhua , Bo Tianwai , Tan Zhongwei , Dong Yi
Published: October 2024

The optical single sideband (SSB) transmitter based on dual modulation of an electro-absorption modulation laser (D-EML) has attracted considerable attention for its capability of monolithic integration and high output power. A model-based modulation method has been developed recently for generating high-quality optical SSB signals with this D-EML scheme. However, this method requires accurate characterization of the EML’s chirps and pre-compensation for frequency responses of all-optical/electrical components, as well as the path difference between two driving signals. This imposes notable requirements on the transmitter characterization in practical applications. In this paper, we propose an adaptive method to approach the required responses of the pre-compensation filters for this optical SSB transmitter. This method avoids cumbersome device characterization and shows great resilience to the variation of system parameters. By using the proposed adaptive method, we generate a 56 Gb/s optical SSB orthogonal frequency-division multiplexed signal with the sideband suppression power ratio exceeding 21 dB. It is convenient with this method to switch the devices, i.e., directly modulated laser (DML) or electro-absorption modulator (EAM), to be pre-compensated for the optical SSB signal generation. Moreover, this method exhibits good tolerance to the path delay (±15 ps) between DML and EAM, as well as modulation depth. We also successfully transmit this signal over 80 km long standard single-mode fiber.
Tunable silicon integrated quantum light source with on-chip FSR-free filters
Authors: Jin Zhanping , Ren Qirui , Liu Dongning , Ren Xiaosong , Huang Yidong , Zhang Wei
Published: October 2024

In this work, we design and fabricate a telecom band quantum light source (QLS) on a silicon photonic chip, which integrates a piece of a long silicon waveguide as the nonlinear medium for spontaneous four-wave mixing (SFWM) and five narrow FSR-free bandpass filters based on a grating-assisted contra-directional coupler (GACDC). Two optical filtering functions of the silicon integrated QLS have been demonstrated. First, the QLS supports two tunable outputs of photon pair generations by four GACDC filters. A wavelength tunable range of 6 nm is demonstrated. Second, one GACDC bandpass filter is designed as an on-chip pump filter before the silicon waveguide. The performances of the QLSs with and without the on-chip pump filter are measured and compared. It shows that the on-chip pump filter has the effect to enhance the performance of the QLS by suppressing the Raman noise photons generated when a pump light propagated in optical fibers before it is injected into the chip. These results show that FSR-free filters would play important roles in developing silicon integrated QLSs.
Integrated subwavelength bimodal interferometer using a multilayer hyperbolic metamaterial
Authors: Máñez-Espina Luis M. , Martínez Alejandro
Published: October 2024

Bimodal interferometry can be implemented in a photonic integrated waveguide by inserting structures supporting—at least—two modes to connect an input and an output single-mode waveguide. The length of the bimodal section is inversely proportional to the index difference between the involved modes, which can be quite small in multimode dielectric waveguides. We propose and numerically demonstrate an ultrashort bimodal interferometer by embedding a multilayer hyperbolic metamaterial in a subwavelength gap separating two dielectric waveguides. We use the large index difference (>1.5) between the bulk and the plasmonic-guided modes of the metamaterial to reduce the total length of the interferometer to less than 1 µm. Our system, which is potentially fabricable with standard nanofabrication tools, could be used to build ultra-compact integrated bimodal interferometers for signal processing and biosensing.
Quasi-distributed acoustic sensing based on optical path difference demodulation for high-frequency and large-amplitude using an optical fiber interferometer array
Authors: Zheng Hongkun , Ma Lingmei , Li Caiyun , Liu Zechao , Zhu Chen , Zhuang Yiyang
Published: October 2024

The phase-sensitive optical time domain reflectometry scheme has attracted great research interest in distributed acoustic sensing (DAS) but suffers from a trade-off between the dynamic range and signal frequency. In this paper, an optical path difference (OPD) demodulation method is applied to an interferometer array composed of an ultra-weak fiber Bragg grating (UWFBG) array and an imbalanced Michelson interferometer to solve this problem. As far as we know, this is the first time that OPD demodulation has been applied to DAS. The UWFBG array is interrogated by a frequency-modulated pulse, and the acoustic signal sensed by the fiber between any two adjacent UWFBGs can be retrieved by demodulating the variation of residual OPD of the interferometer formed by them. The proposed method is analyzed theoretically and validated experimentally; compared with the phase demodulation method, a 100-times boost in bandwidth is achieved for a signal with an amplitude of 0.4 µε. Results also show that the proposed method offers increasing signal-to-noise ratios as the frequency increases.
Spectral broadening of μJ-level pulses around 8 μm in a Germanium-based multi-pass scheme
Authors: Gucci Francesco , Baserga Alessandro , Moretti Luca , Gatti Davide , Corti Matteo , Manzoni Cristian , Cerullo Giulio , Marangoni Marco , Vesco Guglielmo
Published: October 2024

A 2.6-fold spectral broadening of mid-infrared femtosecond μJ-level pulses has been achieved using an unfolded multi-pass configuration of germanium plates and zinc selenide lenses. This method maintains a throughput higher than 60% while preserving the spatial quality and the temporal duration of the input beam. Numerical simulations match the experimental results and show the potential to tailor the parameters of the cell to obtain different spectra.
Lithium niobate electro-optical modulator based on ion-cut wafer scale heterogeneous bonding on patterned SOI wafers
Authors: Li Zhuoyun , Chen Yang , Wang Shuxiao , Xu Fan , Xu Qiang , Zhang Jianmin , Zhu Qiannan , Yue Wencheng , Ou Xin , Cai Yan , Yu Mingbin
Published: October 2024

This paper presents the design, fabrication, and characterization of a high-performance heterogeneous silicon on insulator (SOI)/thin film lithium niobate (TFLN) electro-optical modulator based on wafer-scale direct bonding followed by ion-cut technology. The SOI wafer has been processed by an 8 inch standard fabrication line and cut into 6 inch for direct bonding with TFLN. The hybrid SOI/LN electro-optical modulator operated at the wavelength of 1.55 μm is composed of couplers on the Si layer and a Mach–Zehnder interferometer (MZI) structure on the LN layer. The fabricated device exhibits a stable value of the product of half-wave voltage and length (V
π
L) of around 2.9  V·cm. It shows a good low-frequency electro-optic response flatness and supports 96 Gbit/s data transmission for the NRZ format and 192 Gbit/s data transmission for the PAM-4 format.
Strong photoluminescence enhancement from a WS2 atomic layer integrated on a metallic nanogroove array with intermediate plasmon–exciton coupling
Authors: Su Yingwen , Lu Hua , Li Dikun , Wang Chunyu , Zhao Jianlin
Published: October 2024

The coupling between surface plasmons and excitons in transition metal dichalcogenides (TMDs) plays crucial roles in light emission, nonlinear optics, and quantum information processing. However, the intermediate plasmon–exciton coupling has not been reported in the TMD-integrated metallic nanoarray. Herein, we demonstrate the intermediate coupling behavior between surface plasmons in the silver nanogroove array and excitons in 2D layered tungsten disulfide (WS2). The results show that the reflection spectra of the silver nanogroove array possess an obvious reflection dip at the wavelength of ∼630  nm due to the generation of surface plasmons. The experiment results are well consistent with the numerical simulations. When the silver nanoarray is integrated with a trilayer WS2, there exists a distinct coupling between surface plasmons and A excitons in WS2. The temporal coupled-mode theory analysis shows that the plasmon–exciton coupling locates in the intermediate plasmon–exciton coupling region. The intermediate coupling can give rise to the strong photoluminescence (PL) enhancement of 48-fold in WS2. The wavelength of the PL peak presents a red shift with the increase of the temperature. This work paves a new pathway for the generation of plasmon–exciton coupling and the PL enhancement in atomic-layer TMDs.
Celebrating leadership and innovation—introducing a new interview series with pioneering women in optics and photonics
Authors: Yang Lan
Published: October 2024

Photonics Research Editor-in-Chief Lan Yang introduces the new interview article series.
Environmental DNA as a complementary tool for biodiversity monitoring: A multi-technique and multi-trophic approach to investigate cetacean distribution and feeding ecology
Authors: Afonso Luís , Costa Joana , Correia Ana Mafalda , Valente Raul , Lopes Eva , Tomasino Maria Paola , Gil Ágatha , Oliveira-Rodrigues Cláudia , Sousa Pino Isabel , López Alfredo , Suarez-Bregua Paula , Magalhães Catarina
Published: October 2024

The use of environmental DNA (eDNA) to assess the presence of biological communities has emerged as a promising monitoring tool in the marine conservation landscape. Moreover, advances in Next-Generation Sequencing techniques, such as DNA metabarcoding, enable multi-species detection in mixed samples, allowing the study of complex ecosystems such as oceanic ones. We aimed at using these molecular-based techniques to characterize cetacean communities, as well as potential prey on the northern coast of Mainland Portugal. During four seasonal campaigns (summer 2021 to winter 2022/2023), seawater samples were collected along with visual records of cetacean occurrence. The eDNA isolated from 64 environmental samples was sequenced in an Illumina platform, with universal primers targeting marine vertebrates. Five cetacean species were identified by molecular detection: common dolphin (Delphinus delphis), bottlenose dolphin (Tursiops truncatus), Risso’s dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena) and fin whale (Balaenoptera physalus). Overall, except for the latter (not sighted during the campaigns), this cetacean community composition was similar to that obtained through visual monitoring, and the complementary results suggest their presence in the region all year round. In addition, the positive molecular detections of Balaenoptera physalus are of special relevance since there are no records of this species reported on scientific bibliography in the area. The detection of multiple known prey of the identified dolphins indicates an overlap between predator and prey in the study area, which suggests that these animals may use this coastal area for feeding purposes. While this methodological approach remains in a development stage, the present work highlights the benefits of using eDNA to study marine communities, with specific applications for research on cetacean distribution and feeding ecology.
ESPressoscope: A small and powerful approach for in situ microscopy
Authors: Li Ethan , Saggiomo Vittorio , Ouyang Wei , Prakash Manu , Diederich Benedict
Published: October 2024

Microscopy is essential for detecting, identifying, analyzing, and measuring small objects. Access to modern microscopy equipment is crucial for scientific research, especially in the biomedical and analytical sciences. However, the high cost of equipment, limited availability of parts, and challenges associated with transporting equipment often limit the accessibility and operational capabilities of these tools, particularly in field sites and other remote or resource-limited settings. Thus, there is a need for affordable and accessible alternatives to traditional microscopy systems. We address this challenge by investigating the feasibility of using a simple microcontroller board not only as a portable and field-ready digital microscope, but furthermore as a versatile platform which can easily be adapted to a variety of imaging applications. By adding a few external components, we demonstrate that a low-cost ESP32 camera board can be used to build an autonomous in situ platform for digital time-lapse imaging of cells. Our prototype of this approach, which we call ESPressoscope, can be adapted to applications ranging from monitoring incubator cell cultures in the lab to observing ecological phenomena in the sea, and it can be adapted for other techniques such as microfluidics or spectrophotometry. Our prototype of the ESPressoscope concept achieves a low power consumption and small size, which makes it ideal for field research in environments and applications where microscopy was previously infeasible. Its Wi-Fi connectivity enables integration with external image processing and storage systems, including on cloud platforms when internet access is available. Finally, we present several web browser-based tools to help users operate and manage our prototype’s software. Our findings demonstrate the potential for low-cost, portable microscopy solutions to enable new and more accessible experiments for biological and analytical applications.
Pedagogical strategies for teaching nursing theories in undergraduate students: A scoping review protocol
Authors: Demagny-Warmoes Aurélie , Quindroit Paul , Colson Sébastien
Published: October 2024

From a pedagogical point of view, there is a great deal of creativity and practice in teaching conceptual models and nursing theories. However, there seems to be no synthesis of knowledge regarding the pedagogical methods used to teach them. The purpose of this scoping review is to map the available literature on the teaching of nursing conceptual models and theories in undergraduate nursing education. The scoping review will be developed in accordance with the JBI scoping review methodology and the PRISMA scoping review checklist. The aim of the results is to map the available literature data that can serve as inspiration and a foundation for the development of specific courses on conceptual models and theories in nursing sciences. This scoping review will be served as the basis for a study that will be described and explored the integration of nursing knowledge into bachelor of nursing curricula.
Population and transmission dynamics model to determine WHO targets for eliminating Hepatitis C virus in Thailand
Authors: Astley Jennifer , Saralamba Sompob , Poovorawan Kittiyod , White Lisa Jane , Aguas Ricardo , Pan-ngum Wirichada
Published: October 2024

Background

Hepatitis C Virus is endemic to many areas of Thailand, whose population structure is tending towards older age groups as birth rate and mortality decrease. With around 790,000 cases in 2019, prevalence is still relatively high, but the World Health Organisation has called for elimination of HCV by 2030.

Methods

An age structured compartmental transmission model was used to explore the effectiveness of screening strategies with respect to WHO elimination goals, as well as the effect of changing population structure on the success or failure of such strategies.

Results

Population structure did not appear to affect the timeline of elimination targets and screening individuals over the age of 30 at a high (50% per year) coverage could bring forward achievement of the incidence elimination target by four years compared to baseline (approximately 6% per year). Achievement of mortality elimination targets was not reached until after the end of the simulation (2040), and intensive screening strategies did not appear to lead to incidence elimination by 2030.

Conclusion

The model suggested that with age-targeted screening programmes incidence elimination could be brought forward by several years. However, WHO elimination goals may not be met by 2030.
First evidence of microplastic inhalation among free-ranging small cetaceans
Authors: Dziobak Miranda K. , Fahlman Andreas , Wells Randall S. , Takeshita Ryan , Smith Cynthia , Gray Austin , Weinstein John , Hart Leslie B.
Published: October 2024

Plastic is a ubiquitous environmental contaminant, resulting in widespread exposure across terrestrial and marine spaces. In the environment, plastics can degrade into microparticles where exposure has been documented in a variety of fauna at all trophic levels. Human epidemiological studies have found relationships between inhaled microplastics and oxidative stress and inflammation. Previous studies of bottlenose dolphins (Tursiops truncatus) have reported prevalent exposure to plasticizing chemicals (e.g., phthalates) as well as particle loads in gastrointestinal tracts, but exposure from inhalation has not yet been studied. The objective of this study was to determine if inhalation is a viable route of microplastic exposure for free-ranging dolphins. Exhalation samples were opportunistically collected from dolphins residing in Sarasota Bay, Florida (n = 5) and Barataria Bay, Louisiana (n = 6) during catch-and-release health assessments to screen for microplastic particles. All dolphin samples contained at least one suspected microplastic particle, and polymer composition was determined for 100% of a subset (n = 17) of samples. Additional studies are warranted to better understand the extent of inhaled microplastics, as well as to explore impacts, given potential risks to lung function and health.
Development of a toolkit to help parents/caregivers manage feeding problems in autistic children: A protocol for a realist synthesis and toolkit co-design
Authors: Connor Zoe L. , Atkinson Lou , Bryant-Waugh Rachel , Maidment Ian , Blissett Jacqueline
Published: October 2024

Many autistic children have feeding problems, typically eating a limited range of foods. Feeding problems affect quality of life, health, and development. Research suggests that parents are often unsure when to or whether to seek help. When they do, local provision of help across the UK is often lacking. A toolkit could offer a tailored, accessible, and scalable early intervention to support parents. We aim to develop the blueprint of a toolkit to help parents/caregivers manage feeding problems in their autistic children. Medical Research Council guidance on developing complex interventions informs three successive work packages:

Realist review: a literature search and analysis using realist theory of logic to construct programme theory(s) in line with RAMESES (Realist And Meta-narrative Evidence Syntheses: Evolving Standards) guidance.

Realist evaluation: interviews of three groups: autistic children, young people and adults (experts), parents/caregivers of autistic children (parents), and professionals who help parents manage feeding problems (professionals) across the UK. Analysis of verbatim interview transcripts using realist theory of logic to refine programme theory(s).

Co-design of the toolkit blueprint: behaviour change theory applied to the programme theory(s) will generate candidate components for the online tool. A blueprint (a detailed textual outline) will be co-designed.

A participatory research team of experts, parents, and professionals will be involved in each work package. Where consensus is needed it will be reached by asynchronous nominal group technique. A PPI (public and patient involvement) advisory group of experts and parents will ensure the project is relevant, respectful, and accessible. Findings of each step will be disseminated via journal publications, conferences, social media, as well as PPI-co-produced webinars and a dissemination event. On completion, this project will provide the foundation for the subsequent development and refinement of the prototype toolkit.
A pilot study examining periodontally healthy middle-aged humans and monkeys display different levels of alveolar bone resorption, gingival inflammatory infiltrate, and salivary microbiota profile
Authors: Lin Bingpeng , Pathak Janak L. , Gao Hongbin , Zhou Zijun , Ser Hooi-Leng , Wu Lihong , Lee Learn-Han , Wang Lijing , Chen Jianming , Zhong Mei
Published: October 2024

Background

Monkeys are an appropriate model for periodontal research owing to their similar dental anatomy and physiology unlike humans. Extensive literature exists on pathological periodontitis in monkeys and humans, although concerns regarding whether healthy middle-aged monkeys and humans display the same periodontal and oral microbial status remains unclear.

Aims and objectives

The current study aimed to compare alveolar bone resorption, gingival inflammatory infiltrate, and salivary microbiota profile in periodontally healthy middle-aged humans and monkeys.

Methods

CBCT examination and histological analysis were performed to compare the periodontal status in middle-aged healthy humans and monkeys. Oral saliva16S rRNA sequencing was performed to analyze the oral microbial profile.

Results

The alveolar resorption was compared between humans and monkeys, to determine the periodontal health. The percentage attachment of attachment loss was more around the posteriors teeth in humans when compared to monkeys (p<0.05). The degree of gingival inflammation was analyzed in both the groups, the expression of CD 34,45was higher in humans. 16S rRNA analysis demonstrated less diversity of salivary microorganisms in humans than in monkeys. The relative abundance of Aggregatibacter, Haemophilus, Gemella, and Porphyromonas at the genus level was significantly less in humans than in monkeys (p(<0.05).

Conclusion

The periodontally healthy middle-aged humans and monkeys display different alveolar bone resorption and gingival inflammatory infiltrate levels. Furthermore, the salivary microbiota profile showed distinctly different oral microbiomes in these two primates. Our results suggest that the difference in alveolar bone status and gingival inflammatory infiltrate in healthy humans and monkeys might be associated with the diversity of the oral microbiome.
Decoupling analysis of economic development and human well-being: A case study of the Qinghai-Xizang Plateau, China
Authors: Fan Weiguo , Chen Kehan , Chen Nan , Mengmeng Meng , Wang Xuechao
Published: October 2024

Clarifying the relationship between economic development and human well-being is conducive to promoting high-quality economic development. This study focused on 16 prefecture-level cities in the Qinghai-Xizang Plateau region. The critic weighting method assessed the 2007–2018 human well-being index (HWI). The Tapio decoupling model allowed the study of the human well-being decoupling state. Finally, the drivers of decoupling between economic development and human well-being were analyzed using the Logarithmic Mean Divisia Index method. The results indicated that (1) almost all cities in the study region had an upward 2007–2018 HWI trend, but there were significant differences in growth magnitude and change trend. (2) Economic development and human well-being in the study region in 2007–2018 had expansion negative decoupling, thus, human well-being increased with economic growth, but not as fast as gross domestic product. 9 cities in 2007 showed weak decoupling, expansion connection, and expansion negative decoupling, increasing to 13 cities by 2018, indicating that human well-being development gradually improved from 2007 to 2018. (3) For most cities, the economic scale effect was the most influential factor in the decoupling of economic development and human well-being. Therefore, this study provided policy recommendations for decoupling economic development and human well-being.
Incidence of Occult Hepatitis B Infection (OBI) and hepatitis B genotype characterization among blood donors in Cameroon
Authors: Mbencho Macqueen Ngum , Hafza Nourhane , Cao Le Chi , Mingo Victorine Ndiwago , Achidi Eric A. , Ghogomu Stephen Mbigha , Velavan Thirumalaisamy P.
Published: October 2024

Background

Occult hepatitis B infection (OBI) is characterized by the presence of hepatitis B virus (HBV) DNA at low levels in serum (<200 IU/mL) with a negative hepatitis B surface antigen (HBsAg) test. OBI remains a major challenge to blood safety, particularly in HBV-endemic regions like Cameroon, where HBV detection relies solely on HBsAg testing. This cross-sectional study aimed to investigate the actual incidence and genotype characteristics of OBI in Cameroonian blood donors.

Methods

Between March and June 2023, samples were collected from 288 HBsAg-negative blood donors aged 18 to 55 years and analysed for antibodies against the HBV core (anti-HBc) and surface antigens (anti-HBs). Following DNA extraction from the serum samples, qualitative nested PCR and quantitative real-time PCR were used to detect HBV viral DNA and viral load respectively. For positive samples, sequencing of a fragment of the S gene was performed to identify the circulating HBV genotypes.

Results

The findings revealed that 58% (n = 167/288) of blood donors tested positive for anti-HBc, 29% (n = 83/288) tested positive for anti-HBs, and 26% (n = 75/288) being positive for both anti-HBc and anti-HBs. Occult hepatitis was confirmed in 4.5% of the blood donors, all of whom belonged to either HBV genotypes A or E, which are predominant in Cameroon. The amino acid substitution sA184V associated with HBsAg detection failure in genotype E was observed in 70% of OBI sequences, and the HBsAg immune escape variants (sT131N and sS143L) implicated in OBI were also observed. The mutation rtN139K in the reverse transcriptase (RT) domain of the overlapping HBV polymerase (P) gene was present in 17% of OBI-positive sequences of genotype E, likely contributing to masking HBsAg secretion.

Conclusion

The results suggest a considerable risk of transfusion-transmitted HBV in this region. Therefore, to ensure blood safety, nucleic acid testing (NAT) is recommended, as relying solely on HBsAg assays is insufficient to eliminate this risk.
Efficacy and safety of short segment pedicle screw fixation in patients with neurologically intact burst fractures of the lower thoracic and lumbar spine: a meta-analysis of studies published over the last 20 years
Authors: Grin A. A. , Talypov A. E. , Kordonskiy A. Yu. , Karanadze V. A. , Lvov I. S. , Smirnov V. A. , Abdrafiev R. I.
Published: October 2024

Objective. To conduct a systematic review and meta-analysis of studies on the surgical treatment of patients with uncomplicated burst fractures of the lower thoracic and lumbar spine and to determine the effectiveness and safety of short transpedicular fixation (TPF) in this patient group.

Material and Methods. The study included articles with the following criteria: publication date from January 1, 2004, to December 31, 2023; patient sample descriptions involving uncomplicated burst fractures from T10 to L5; TPF involving one segment adjacent to the fractured vertebra in both cranial and caudal directions without spinal fusion; descriptions of treatment outcomes or complications; and an average follow-up period of at least 12 months. Meta-analysis was conducted using the Comprehensive Meta-Analysis software, version 2.2.064. Depending on the level of heterogeneity (I² test), either a fixed-effects or random-effects model was applied. Begg’s or Egger’s test was used to assess publication bias, and any bias present was corrected using the trim-and-fill method.

Results. The application of TPF resulted in a significant reduction in the overall Cobb angle by 5.9 degrees in the percutaneous group and by 7.6 degrees when using a midline approach. Regarding AVBCR (anterior vertebral body compression ratio), a reduction of 24.0 % and 24.8 % was observed in both groups, respectively. The overall complication rates were as follows: superficial infection, 2.2 %; deep infection, 2.0 %; and implant-associated complications, 5.6 %. No patient developed a neurological deficit. The levels of work adaptation W1 and W2 on the Denis scale were achieved in 70.9 % of patients. The overall quality of life, as measured by the Oswestry Disability Index, averaged 13.4 %.

Conclusions. Short transpedicular fixation without additional spinal fusion or laminectomy appears to be an effective and safe method for treating burst fractures of the lower thoracic and lumbar spine without neurological deficits. This method allows for regression of kyphotic deformity in the long-term post-injury period by at least 5.9 degrees and restoration of anterior vertebral height by 24 %. The approach demonstrated relatively low overall postoperative complication rates. More than 90 % of patients were able to return to full-time work, either in their previous position or with reduced physical demands.
Perioperative and early complications of extended instrumental fixation for spinal deformity in children: what does the application of the Clavien – Dindo classification reveal and what questions does it raise?
Authors: Mushkin A. Yu. , Petukhova V. V. , Pershin A. A. , Maletin A. S. , Malamashin D. B. , Kuklina S. A. , Evseev V. A. , Kostik M. M.
Published: October 2024

Objective. To analyze complications of extended posterior instrumental fixation for spinal deformity in children in accordance with the Clavien – Dindo classification and to assess its information content and limitations.

Material and Methods. A retrospective single-center cohort study included 136 patients aged from 1 year to 17 years 11 months consecutively operated in 2020–2023 for thoracic and lumbar spine deformities associated with congenital, neuromuscular, syndromic, idiopathic scoliosis and Scheuermann’s kyphosis. At least four spinal motion segments were included in the zone of posterior instrumental fixation. All perioperative events and postoperative complications noted in the medical records were registered in accordance with the Clavien – Dindo classification. An analysis of factors influencing the development of complications of grade IIIB and higher was carried out.

Results. With a total apparent high number of complications/events (55 or 40.4 % of the number of operations), the vast majority of them correspond to grade I–II (41; 30.1 %) and do not affect the tactics and outcome of treatment. Complications of grade III and IV were noted in 13 (9.6 %) cases, and of grade V – in 1 (0.7 %) case. The influence of deformity etiology, gender, age or underweight on the risk of grade IIIB and IVA complications was not revealed, which may be due to the limited number of observations. The installation of more than 18 transpedicular screws, which correlated with surgery duration and blood loss volume, was significant for the development of such complications. The results obtained were compared with those presented in the literature, the information content and limitations of the use of the Clavien – Dindo classification in spine surgery were discussed.

Conclusion. A significant part of the complications of spinal deformity correction in children is conventionally not taken into account in domestic practice and, accordingly, cannot be prevented. The use of the Clavien – Dindo classification allows estimating the frequency of complications that potentially do not affect (grade I–II) and affect (grade III–IV) the tactics of postoperative treatment and outcomes. The installation of 18 or more supporting elements of instrumentation is directly related to surgery duration, intraoperative blood loss volume and the risk of developing grade IIIB and IVA complications. Larger data sets are needed for a more objective analysis of the risk of severe complications for each nosology.
Revision surgery for chronic pyogenic spondylitis: analysis of a monocenter cohort with a minimum 1 year follow-up
Authors: Naumov D. G. , Mushkin A. Yu. , Vishnevsky A. A.
Published: October 2024

Objective. To analyze the structure of complications and follow-up results of revision surgeries in patients operated on for chronic nonspecific spondylitis (CNS).

Material and Methods. Revision interventions due to the development of complications corresponding to type IIIB according to Clavien – Dindo classification were performed in 78 patients (mean age 58 years 6 months ± 11 years 2 months) with CNS who had previously undergone reconstructive surgery on the spine. The timing of complications was analyzed according to Prinz classification. The structure of complications and factors potentially influencing their development were evaluated. Predictors of infectious and orthopedic complications were differentiated.  Follow-up period was at least 1 year (M ± m = 3 years 3 months ± 1 year 2 months). Statistical analysis was performed using SPSS, version 22.0.

Results. The estimated frequency of Clavien – Dindo grade IIIB complications after surgical treatment of CNS was 11.3 %. In 44 (56.4 %) of 78 cases, indications for revision surgery were due to infectious complications, and in 34 (43.6 %) – to orthopedic complications. The Charlson comorbidity index was 4.5 ± 1.8 with no intergroup differences between infectious and orthopedic complications (p = 0.052). The duration of primary interventions (p < 0.001) and blood loss (p = 0.010) were higher in patients with infectious complications. The average preoperative ODI was 48.3 ± 13, with a higher value in the infectious complications group (F = 5.146, p = 0.026). The timing of complications and the location of primary reconstruction influenced both the ODI score (F = 6.622, p < 0.001) and the type of complications (Pearson’s χ2 = 14.224, p = 0.014). The patient age had no effect on the location of complications (p = 0.349, F value = 1.137). Preoperative neurologic deficit was noted in 23 patients, regression was recorded in 11 cases, including complete in 6 and within the same functional class in 5 cases. The complication rate in the long-term period after revision surgery was 14.1 %.

Conclusion. Infectious complications of primary interventions in patients with chronic nonspecific spondylitis prevail over orthopedic ones. Significant predictors of the development of complications are the patient age > 55 years, the Charlson comorbidity index > 3, duration of surgery > 2 hours 30 minutes, and blood loss volume > 250 ml.
L5–S1 Spondylolisthesis: What Has Changed in 20 Years? A Review of Key Issues in Comparison with Personal Experience
Authors: Nazarenko A. G. , Vetrile M. S. , Kuleshov A. A. , Makarov S. N. , Lisyansky I. N. , Zakharin V. R. , Sharov V. A. , Aganesov N. A.
Published: October 2024

The very first issue of the Russian Journal of Spine Surgery (2004;(1):39–46) published an article entitled “Surgical Treatment for L5 Spondylolisthesis with Transpedicular Fixators”. Twenty years later, the authors analyzed changes in approaches to surgical treatment of spondylolisthesis, taking into account the experience in surgical treatment of this pathology gained at the N.N. Priorov National Medical Research Center of Traumatology and Orthopaedics. The issues of classification, fixation methods, reduction, changes in sagittal balance, the possibility of using additive technologies and possible complications of surgical treatment are considered.

In conclusion, it is noted that the development of surgical treatment methods, the study of biomechanical features, the introduction of additive technologies and much more enable improving the outcomes of spondylolisthesis treatment.