bluuebunny/crossref_metadata_2025 huggingface dataset:
Qualitative Content Analysis of Code-Switching Behaviors in Kannada-English Bilingual Adults Who Stutter
Authors: Manivannan Vasupradaa , Maruthy Santosh
Published: July 2024

Objectives: The present study investigated whether code-switching (CS) behaviors help manage stuttering. If yes, how does CS help manage stuttering in the daily life of Kannada-English bilingual adults who stutter (BAWS)? Methods: A convenient purposive sample of 35 Kannada-English bilingual adults who stutter, aged 18-40 years, were recruited for the study. The participants completed a Google form which contained a descriptive question. The question was, (a) Is language mixing or switching helpful in managing stuttering?, (b) If yes, describe how managing your stuttering in day-to-day life is beneficial. Results: 30 of 35 BAWS (85.71%) responded “Yes” to question (a). Furthermore, a significant theme and five sub-themes were created based on their descriptive responses. It includes a significant theme of personal growth and sub-themes such as communication, coping, conceptualization, social image and reputation, and psychological strength. Conclusion: The present study results suggest that Kannada-English BAWS perceive that their CS behaviors help to avoid stuttering. Furthermore, it builds their speaking skills, management strategies, understanding of others, social image, and confidence—overall personal growth. Nevertheless, avoidance behaviors, such as code-switching, are ineffective long-term stuttering management strategies and lower BAWS self-esteem by preventing individuals from facing challenges or speaking complex words or phrases.
Reading Comprehension and Comprehension Monitoring in First-grade Children with Vocabulary Delay
Authors: Yoon Hyojin
Published: July 2024

Objectives: This study investigated reading comprehension and reading comprehension monitoring abilities of children with vocabulary delay at the end of the first grade. Specifically, the study examined whether children with vocabulary delays could detect internal inconsistency errors, which are contradictory pieces of information in a short story, and whether they could correct those errors to make appropriate changes to the story at the beginning stage of reading. Methods: Fourteen children with vocabulary delay and 15 typically developing children participated in this study. Each child read 10 short stories without internal inconsistency errors and 10 stories with internal inconsistency errors. After reading the text, children were asked to find any inconsistent parts of the story and correct them. Results: The results showed that children with vocabulary delay performed worse on reading comprehension than their peers. They also scored statistically lower on both the error detection and error correction tasks in stories with internal inconsistency errors compared to typically developing children. For typically developing children only, there were significant correlations between reading comprehension and reading comprehension monitoring. Conclusion: Children with vocabulary delay exhibited difficulties in both reading comprehension and comprehension monitoring. Poor vocabulary knowledge can hinder their ability to recognize when a text is misunderstood or to apply effective strategies for resolving problems, ultimately leading to reading comprehension failure. This suggests that children with language disorders, including those with vocabulary delays, need to be assessed and provided with interventions for both reading comprehension and comprehension monitoring.
Longitudinal Observation of Text Reading Fluency in 1st Graders with and without Dyslexia
Authors: Yu Haerim , Pae Soyeong
Published: July 2024

Objectives: Text reading fluency is an important skill for students using Korean which has a transparent orthography system. This study longitudinally observed text reading fluency in Korean first-grade students with and without dyslexia over 3 semesters. Methods: Forty children with dyslexia and forty typically developing children participated in the study. They were grouped based on their performance at the beginning of the second grade. All students exhibited normal levels of listening comprehension and nonverbal intelligence. Over the three semesters, participants read six texts at various decoding levels. We then analyzed the number of correctly read syllables per 10 seconds, text reading accuracy, and speed. Results: Both the dyslexia and typically developing group showed significant differences in the number of syllables read per 10 seconds at all time points. Text reading accuracy improved significantly from first to second semester of first grade for both the dyslexia and typically developing group. By first semester of second grade, students with dyslexia achieved approximately 80% accuracy. While dyslexic students’ reading speed significantly improved from second semester of first grade to the first semester of second grade, they remained slower than typically developing students. Typically developing students showed consistent improvements in reading speed across all time points. Conclusion: When intervening with lower-grade students with dyslexia in Korea, it’s crucial to conduct not only decoding but also text-level fluency activities. Providing individualized texts that are decodable for dyslexic children seems to be essential.
The Effect of PA Intervention through Remote Collaboration for CCK
Authors: An Eun-Sol , Jeon Ji-Hye , Lee Min-Ju , Kim Young Tae
Published: July 2024

Objectives: This study aimed to examine the effects of a phonological awareness and phonics intervention through remote collaboration between SLPs and teachers on the decoding skills of children from multicultural families with poor reading in the lower grades of elementary school. Methods: In this study, a multi-probe design was used to verify the effect of the intervention. The subjects were 3 multicultural children with poor reading skills (grades 1-2) and 3 teachers for each child. Their reading skills were examined through tests of phonological awareness and decoding (word level) in the baseline, intervention, and maintenance phases. Additionally, tests of decoding (sentence level) were conducted in the generalization phase to examine generalization at the sentence level. In this study, SLPs provided instruction to each child twice a week and also provided guide videos to each teacher once a week for 2 months. Results: All children were found to have high improvements in decoding skills (word level) and phonological awareness skills. Additionally, as a result of standardized reading and writing test (QRW), all children’s post-intervention raw scores were improved in all areas. In the generalization phase, all children showed improvements in decoding skills (sentence level). In the maintenance phase, all children were found to have a large effect size. Conclusion: The results show that phonological awareness and phonics intervention through remote collaboration between two experts had positive effects on the decoding skills of multicultural children with poor reading. Also, this intervention improved teachers’ teaching efficacy. Thus, the implementation of studies for collaboration between experts is suggested.
The Effects of Phonics Training based on Phonological and Morphological Awareness on Reading and Writing Abilities in Children with Reading Difficulties
Authors: Byun Se-Jin , Kim Soo-Kyung , Jung Kyunghee
Published: July 2024

Objectives: The purpose of this study is to find more efficient intervention methods for children with poor reading by comparing phonics intervention based on phonological awareness and with integrated phonics group including morphological awareness. Methods: 18 children with poor reading skills in elementary school were selected and classified into two experimental groups and a control group. Decoding, paragraph reading fluency, reading comprehension, dictation, and sentence reading and writing tests were administered as assessment tool. Additionally Jung (2014)’s morphological awareness ability task was utilized. Results: First, both experimental groups showed a significant increase in decoding skills. However, in terms of reading comprehension and fluency, there was a significant increase in the integrated phonics training group including morphological awareness, but there was no significant difference in the phonics training group based solely on phonological awareness. The control group did not show a significant increase in all areas. Second, both groups showed a significant improvement in the dictation skills, while the control group did not showed significant difference. Third, both experimental groups significantly increased their scores in phonological awareness tasks and morphological awareness ability tasks. Conversely, there was no significant increase observed in the control group. Conclusion: It is significant that the phonics intervention program, which integrates phonological and morphological awareness for children with poor reading skills, has an effect not only on reading and writing, but also on meta-recognition ability. This indicates that interventions, including morphological awareness training, have a broad impact on the realm of reading.
Exploring Bilingual Benefits: Verbal and Nonverbal Information Updating in Working Memory
Authors: Jung Koeun , Luvsantseren Azzaya , Min Yoonki
Published: July 2024

Objectives: The present study aimed to confirm the cognitive advantages of bilingualism specifically in the domain of working memory updating. Methods: A total of sixty adults (aged 20 to 26) participated in the study, divided into three groups based on bilingual status: Bilingual-similar (n = 20), Bilingual-Mongolian weighted (n = 20), and Monolingual (n = 20). Participants completed working memory update tasks involving verbal or nonverbal stimuli. Information updated in working memory could be derived from perceptual input or long-term memory. Results: Bilingual advantages in working memory updating was found in both verbal and nonverbal task. The advantages in working memory updating depending on stimuli (verbal or nonverbal) exhibited similar patterns. However, the patterns of bilingual advantages varied depending on the source of information (perceptual input or long-term memory). While both bilingual groups showed advantages when the information source was perceptual input, only the Bilingual-similar group showed advantages when the source was long-term memory. Conclusion: The study provides further empirical support for the cognitive benefits associated with bilingualism, particularly in the realm of working memory updating. The current findings underscore the notion that bilinguals optimize domain-general cognitive control. Further research is needed to investigate the underlying mechanisms of information management in bilingual individuals across different information resources.
Analysis of Language Developmental Supporters for Multicultural Family’s Perception and Demand on IT-based Pragmatic Language Intervention
Authors: Yun So Jeong , Jung Sang-Im , Choi Younjung , Kim Young Tae
Published: July 2024

Objectives: This survey study investigated the perception of supporters of language development for multicultural families (the supporters) in regards to the pragmatic language difficulties of multicultural children, the importance of intervention, and the demand for an IT-based pragmatic language intervention program. Methods: Among a total of 300 supporters across the country, 159 completed questionnaires, which were used for the analysis. The questionnaire consisted of the respondents’ background information; experience of pragmatic language intervention; perception of pragmatic language difficulties of multicultural children and importance of intervention, and demands of IT-based pragmatic language intervention program. Results: The supporters with 4 years or more of experience reported the children to have greater pragmatic language difficulties compared with those with those with less than 4 years of experience. No statistically significant differences were found in the perceptions of the importance of pragmatic language intervention for multicultural children. The supporters indicated that the most useful IT-based pragmatic language intervention program would be ‘materials offer type’, followed by ‘pragmatic-language-intervention-related parent education type’, and ‘evaluation type’ respectively. Also, the respondents indicated that ‘pragmatic-language-intervention-related parent education type’ would be the most useful for the parents followed by ‘problem solving type’, and ‘learning type’ in the order listed. Conclusion: The supporters were highly aware of the pragmatic language difficulties of multicultural children and the importance of intervention, and the survey results indicated that they needed active support. The results of this study can be used as basic data when a follow-up study is conducted to develop an IT-based pragmatic language intervention program.
Children's home challenges
Authors: Stephenson Jo
Published: July 2024

Ofsted has published a series of research reports on the children's home sector, providing insight into issues from a lack of suitable care placements to post-pandemic staffing shortages, finds Jo Stephenson
Children learn the importance of their rights
Authors: Goddard Charlotte
Published: July 2024

Programme puts UN Convention on the Rights of the Child into practice, helping children to understand their rights and creating fairer systems in schools
SEND reforms consultation: five key issues sector wants resolved
Authors: Simpson Fiona
Published: July 2024

Sector leaders, unions and parent groups highlight concerns over whether SEND green paper proposals to change EHCP arrangements, train more staff and improve support in mainstream schools are achievable
Fractals as Julia and Mandelbrot Sets via S-iteration
Authors: Padaliya Sanjay Kumar , Sharma Saurabh , Singh Jasvinder Pal
Published: July 2024

To understand the phenomena of expanding symmetries Fractals patterns are an important tool which exhibit similar patterns for different scales. In the present paper, establishing an escape criteria by using S-iteration process to visualize fractals namely Julia and Mandelbrot sets for the function F(w)=aewp+c where c,a∈ C and p≥2. The result obtain is a generalization of the existing algorithm and technique providing fractals for different parameter values. Also, the time taken to obtain fractals for different parameters by using computer software MATLAB is computed in seconds.
Bilateral Anterior Cruciate Ligament Reconstruction with All-Inside Technique for Adolescent: A Review of the Literature and Case Report
Authors: Rutnagur Joshua D ,   Department of Trauma and Orthopaedics, Royal Aberdeen Childrens’ Hospital, Aberdeen, Scotland, United Kingdom,, Neilly David , Barker Simon , Dixon James ,   Department of Trauma and Orthopaedics, Royal Aberdeen Childrens’ Hospital, Aberdeen, Scotland, United Kingdom,,   Department of Trauma and Orthopaedics, Royal Aberdeen Childrens’ Hospital, Aberdeen, Scotland, United Kingdom,,   Department of Trauma and Orthopaedics, Aberdeen Royal Infirmary, Aberdeen, Scotland, United Kingdom.
Published: July 2024

Introduction: Simultaneous bilateral anterior cruciate ligament (ACL) ruptures are rare, especially in the pediatric population, with very limited evidence. We aimed to review the current literature and present a case study of an adolescent patient who underwent bilateral reconstruction with hamstrings autograft in a single-stage with a partial transphyseal “all-inside” technique. Literature Review: The limited evidence reports that the incidence of growth disturbance following ACL reconstruction in the skeletally immature is 2.6% with no significant difference between a partial transphyseal and an all-epiphyseal technique. Regarding graft choice in the skeletally immature, no significant difference has been found in function using hamstrings versus bone-to-bone patella autograft. The all-inside technique has shown good outcomes in the skeletally immature with no cases of growth disturbance observed in the literature reviewed. Patients spend less days in hospital and return to sport sooner following simultaneous reconstruction versus staged. Case Report: A 15-year-old male footballer underwent simultaneous reconstruction of bilateral ACL ruptures through a partial transphyseal “all-inside” technique with hamstrings autografts. He began physiotherapy according to local protocol and was discharged from hospital on Day 4 post-operative. He returned to competitive sports 11 months postoperatively with no intraoperative or post-operative complications. Conclusion: This case suggests that bilateral simultaneous ACL reconstruction is a safe management strategy in the rare case of bilateral ruptures in the skeletally immature, which adds to the evidence base. The number of required hospital stays was reduced and there was return to sport in a comparative time frame to unilateral ACL reconstruction rehabilitation. Keywords: Anterior cruciate ligament, bilateral, all-inside, adolescent, pediatric, knee.
Modification of Pelvic Support Osteotomy Technique in Patients with Sequelae of Hip Dysplasia: A Case Series
Authors: Huanca-Mamani Lidia ,   Department of Pediatric Othopaedic, National Institute of Rehabilitation “Luis Guillermo Ibarra Ibarra”, Av México-Xochimilco 289, Arenal de Guadalupe, Tlalpan, México City,, Mendoza-Jiménez Mauricio , Cuevas-Olivo Ramiro , Arenas-Sordo María de la Luz ,   Department of Pediatric Othopaedic, National Institute of Rehabilitation “Luis Guillermo Ibarra Ibarra”, Av México-Xochimilco 289, Arenal de Guadalupe, Tlalpan, México City,,   Department of Pediatric Othopaedic, National Institute of Rehabilitation “Luis Guillermo Ibarra Ibarra”, Av México-Xochimilco 289, Arenal de Guadalupe, Tlalpan, México City,,   Department of Genetics, National Institute of Rehabilitation “Luis Guillermo Ibarra Ibarra”Av México-Xochimilco 289. Arenal de Guadalupe, Tlalpan, México City.
Published: July 2024

Introduction: The management of hip dislocation in patients older than 9 years of age is a challenge in terms of deciding which is the best treatment course to follow since the main sequelae are as follows: pain, discrepancy in the length of the pelvic extremities and lame gait, with the consequent disability for activities of daily living. In Ho Choi, Thabet A mention limited treatment options, including total hip arthroplasty and hip arthrodesis. These options have their benefits and limitations. The pelvic support osteotomy initially indicated for the treatment of septic arthritis of the hip and performed for the first time by Bavoier in 1838 and modified in 1970 by Ilizarov aims to improve the aforementioned sequelae. These cases report showed us the functional improvement with the treatment of dislocated hip dysplasia with pelvic support osteotomy with monolateral fixator and the 2nd osteotomy 4 cm distal to the hip. This was corroborated through the application of the modified Harris test. Case report: A series of six female Mexican adolescent patients from 11 to 17 years of age who come to the clinic due to long-standing pain symptoms in the coxofemoral joint, three patients in the right and three in the left hip when walking. All were treated with pelvic support osteotomy. The six patients continued with mild positive Trendelenburg but all of them diminished the discrepancy in the pelvic extremities, the mobility arcs were preserved and pain was suppressed in all. The modified Harris test showed increased scores (103.3%) after the surgery. There was just a minor complication in a patient, and it was resolved with surgical lavage. Conclusion: The modifications in the technique, monolateral fixator and second osteotomy 4 cm from the first one, allowed our patients to present functional improvement at the hip, which was assessed with the modified Harris scale. Patients achieved independent walking without pain and Trendelenburg less evident. The changes we found in our patients are evidence of the goodness and effectiveness of this type of osteotomy in patients older than 9 years of age, to improve the function of the hip. Keywords: Pelvic support osteotomy, Hip instability, Hip dislocation, external fixator.
Fabrication and characterization of optical filters from polymeric aerogels loaded with diamond scattering particles
Authors: Barlis Alyssa , Guo Haiquan , Helson Kyle , Bennett Charles , Chan Carol Yan Yan , Marriage Tobias , Quijada Manuel , Tokarz Ariel , Vivod Stephanie , Wollack Edward , Essinger-Hileman Thomas
Published: July 2024

We have developed a suite of infrared-blocking filters made by
embedding diamond scattering particles in a polyimide aerogel
substrate. We demonstrate the ability to tune the spectral performance
of the filters based on both the composition of the base aerogel
material and the properties of the scattering particles. We summarize
the fabrication, optical modeling, and characterization of these
filters. We investigate two polyimide base aerogel formulations and
the effects of loading them with diamond scattering particles of
varying sizes and relative densities. We describe a model for the
filters’ behavior using a combination of Maxwell Garnett and Mie
scattering techniques. We present optical characterization results for
diamond-loaded aerogel filters with cutoff frequencies (50%
transmittance) ranging between 2.5 and 15 THz, and confirm that
the measured spectral performance is in agreement with our optical
models. We also measure the filters’ refractive indices in the
microwave and report findings in agreement with Maxwell Garnett model
predictions (typically n<1.08).
Topological states in Penrose-square photonic crystals
Authors: Zhang Qichen , Chen Jianzhi , Liu Dongyang , Liu Jianjun
Published: July 2024

Topological edge states (TESs) and topological corner states (TCSs) in
photonic crystals (PCs) provide an effective way to control the
propagation and localization of light. The topological performance of
integrated photonic devices can be improved by introducing the basic
structural unit of photonic quasicrystals (PQCs) into PCs. However,
the previous works arranged the basic structural unit of Stampfli-type
and 12-fold Penrose-type photonic quasicrystals into triangular
lattices, which have a complex structure and allow light to only
propagate around 60° or 120° corners, limiting their applications. In
this paper, a Penrose-square PC is proposed, which realizes both TESs
and TCSs, and light successfully propagates around 90° corners. This
work may reduce the difficulties encountered in the preparation of
topological photonic crystals (TPCs) structured by arranging the basic
structural units of PQCs periodically. It also provides a new, to the
best of our knowledge, platform for studying TPCs and new ideas for
improving the performance of integrated photonic devices.
Kilohertz-linewidth and low-threshold single-frequency all-fiber laser utilizing self-developed Nd3+-doped fluoro-sulfo-phosphate fiber
Authors: Li Zhongxian , Zhu Jinzhong , Ji Yao , Li Jialong , Yang Changsheng , Zhao Qilai , Wang Weichao , Zhang Qinyuan
Published: July 2024

Compared to Nd: YAG lasers, Nd3+-doped fiber lasers offer superior beam quality, compactness, and heat dissipation, especially in generating single-frequency lasers, which holds great promise for applications in optical atomic clocks, quantum computing, and high-precision bio-photonic imaging. In this study, theoretical simulations of the local environment and experimental analyses on the luminescent characteristics of what we believe to be a novel Nd3+-doped fluoro-sulfo-phosphate (FSP) laser glass were performed to mitigate the concentration and hydroxyl quenching effects. Based on that, a highly Nd3+-doped (4 mol%) FSP fiber with a large emission cross-section (3.24 × 10−20 cm2), wide bandwidth (33.7 nm), long lifetime (354 µs), and high gain coefficient (4.24 dB/cm) was designed. Utilizing this fiber, a 1065 nm SFFL with a low pump threshold of 18 mW, a narrow linewidth of 6.5 kHz, and a 0.9 µm compact all-fiber laser were demonstrated, highlighting the potential of Nd3+-doped FSP fiber in high-performance fiber lasers.
Characterizing the propagation evolution of optical vortex lattices in astigmatic transformations of frequency-doubled laser modes
Authors: Tung J. C. , Chen B. H. , Sung C. K.
Published: July 2024

We develop a wave representation to characterize the propagation evolution of vortex lattice beams, which are produced through a frequency-doubling process of various high-order laser modes, followed by mode conversion. Their phase fields and phase gradients are further analyzed to verify the topological charge for each isolated vortex, as well as the symmetry and net charges of the vortex lattices. In the experiment, we demonstrate the generation of frequency-doubled high-order modes by utilizing an off-center pumped solid-state laser combined with intracavity second-harmonic generation. Subsequently, we employ an astigmatic mode converter to transform the generated frequency-doubled laser modes, obtaining vortex arrays. The strong agreement between theoretical analysis and experimental data not only validates the derived formula but also confirms the creation and characteristics of the vortex lattice beams.
PAM4-modulated 2-micron band for enhanced indoor optical communications: experimental evaluation
Authors: Yang Yatao , Cai Junfei , Song Yufeng , Wang Zhenhong , Wu Weijie , Ji Jianhua
Published: July 2024

This research explores the application of PAM4 modulation to optical signals in the 2-μm wavelength band for indoor optical communication. Experiments conducted in a simulated atmospheric turbulence environment demonstrated a BER of 10−5 for the 2-μm laser carrier with PAM4, surpassing the forward error correction threshold. Power loss comparisons to a back-to-back setup showed minimal degradation under various turbulence levels, with losses of 1.80 dB, 1.91 dB, 2.09 dB, and 2.55 dB for non-turbulent, weak-turbulent, moderate-turbulent, and strong-turbulent conditions, respectively. The system's sensitivity was measured at -7.69 dBm, emphasizing its effectiveness in detecting low-power signals. OptiSystem simulations indicated that PAM4 necessitates a higher optical OSNR than NRZ, suggesting the necessity for sophisticated signal processing techniques for systems operating in the 2-μm band. The study's results contribute to the body of knowledge on high-bandwidth optical communication and suggest future research avenues aimed at enhancing system performance while maintaining cost-effectiveness.
Ultra-short and highly efficient metamaterial Fresnel lens-assisted taper
Authors: Pascar Leonid , Xu Dan-Xia , Grinberg Yuri , Sajjanam Morrison Sunami , Vachon Martin , Liboiron-Ladouceur Odile
Published: July 2024

This paper demonstrates the benefits of leveraging free-space optics concepts in the design of certain integrated photonic components, leading to a footprint reduction without compromising on performance. Specifically, we present ultra-short, highly efficient and fabrication-friendly mode-size converters based on metamaterial Fresnel lens-assisted tapers. This is achieved using a parameterized inverse-design approach, where the metamaterial phase shifters are realized using fabrication-friendly Manhattan geometries, by optimizing the width, length, and position of the phase shifters. This approach overcomes the limitations of the conventional method that uses local periodic approximation, which is not suitable for lenses with a short focal length and high numerical aperture. We also extend the free-space concept of compound lenses and demonstrate a doublet-based taper to further reduce the footprint. The devices are fabricated and experimentally characterized in terms of insertion loss and signal integrity at high data transmission rates, exhibiting high performance. For the singlet, it effectively achieves mode-size conversion from 15 μm to 0.5 μm within a 15 μm distance, leading to ×10 length reduction compared to a linear taper. The insertion loss is under 1 dB over the entire C-band. The doublet achieves the same mode-size reduction within a 10 μm distance, leading to ×15 length reduction compared to a linear taper. The insertion loss is near 1 dB over most of the C-band. In both cases, the signal integrity is maintained for up to 50 Gbit/s.
Fast finite difference solver for optical microscopy in deep biological tissue
Authors: Shanavas Thariq , McLeod Robert R. , Siemens Mark E. , Gopinath Juliet T.
Published: July 2024

Optical scattering poses a significant challenge to high-resolution
microscopy within deep tissue. To accurately predict the performance
of various microscopy techniques in thick samples, we present a
computational model that efficiently solves Maxwell’s equation in
highly scattering media. This toolkit simulates the deterioration of
the laser beam point spread function (PSF) without making a paraxial
approximation, enabling accurate modeling of high-numerical-aperture
(NA) objective lenses commonly employed in experiments. Moreover, this
framework is applicable to a broad range of scanning microscopy
techniques including confocal microscopy, stimulated emission
depletion (STED) microscopy, and ground-state depletion microscopy.
Notably, the proposed method requires only readily obtainable
macroscopic tissue parameters. As a practical demonstration, we
investigate the performance of Laguerre–Gaussian (LG) versus
Hermite–Gaussian (HG) depletion beams in STED microscopy.
Ultra-compact and polarization-insensitive silicon waveguide 3 × 3 star-crossing based on composite subwavelength grating metamaterials
Authors: Yu Qianli , Guo Zhenzhao , Zhu Jiabao , Zhang Lei , Hao Peng , Xiao Jinbiao , Feng Ting , Wu Shengbao
Published: July 2024

We present what we believe is the first report on a polarization-insensitive 3 × 3 silicon star-crossing utilizing a composite subwavelength metamaterial waveguide structure. Two different types of subwavelength grating metamaterials (nanohole grating and fan-shaped bent subwavelength grating) are respectively used to address diffraction issues in the crossing region and mode interference issues caused by a compact non-adiabatic design. This approach results in a device with an ultra-compact footprint of 12.68 × 10.98 µm2 on a standard 220 nm silicon-on-insulator (SOI) platform. Simulation results show low insertion loss (IL) values of <0.2 dB/0.3 dB and suppressed cross talk (CT) levels of <−27.2 dB/−23.6 dB for TE/TM polarizations across a wavelength range of 100 nm (1500–1600 nm). Experimental measurements of the fabricated devices confirm outstanding performance, with IL values of <0.35 dB/0.4 dB and CT levels of <−31.5 dB/−28.6 dB for TE/TM polarization in the C-band.
Cross-phase modulation induced microcomb generation in the normal-dispersion region
Authors: Yang Bofan , Lu Yiyang , Li Shangyuan , Zheng Xiaoping , Xue Xiaoxiao
Published: July 2024

Microcomb generation in the normal-dispersion region usually requires specially designed microresonators with mode interactions, increasing the complexity of device design and control. Here we demonstrate a novel, to the best of our knowledge, scheme of frequency comb generation by bidirectionally pumping an ordinary normal-dispersion microresonator. The cross-phase modulation from the counter-propagating light reshapes the cavity response, facilitating the emergence of modulational instability for comb initiation. By properly adjusting the pump power ratio and frequency detuning in two directions, frequency combs can be formed at any pumped resonance. The proposed method provides a universal pathway to flexible microcomb generation in the normal-dispersion regime.
Dual-driving parametric locking of GHz phonon sources to sub-hertz linewidth in optomechanical systems
Authors: Tang Jin-Dao , Xia Zi-Wei , Bin Qian , Lü Xiao-Min , Zeng Li-Ping , Chen Pei-Qin , Jiang Qin-Yuan , Wang You , Song Hai-Zhi , Zhou Qiang , Zhou Heng , Arutyunov Konstantin Yu. , Lü Xin-You , Huang Yong-Jun , Guo Guang-Can , Deng Guang-Wei
Published: July 2024

In the exploration of collective dynamics and advanced information processing, synchronization and frequency locking of mechanical oscillations are cornerstone phenomena. Traditional synchronization techniques, which typically involve a single mechanical mode, are limited by their inability to distinguish between intrinsic mechanical oscillations and external signals after locking. Addressing this challenge, we introduce a parametric approach that enables simultaneous frequency locking of two gigahertz mechanical modes within an optomechanical crystal cavity. By modulating the pump light to match the sum and difference frequencies of the mechanical modes, we significantly narrow their linewidths from tens of kilohertz to below 1 Hz at room temperature and ambient pressure. This dual-locking scheme also drastically reduces the phase noise of the mechanical modes by 76.6 dBc/Hz at a 100 Hz offset, while allowing flexible tuning of the locked modes’ frequencies via input signal adjustments. Our method not only facilitates direct observation of mechanical oscillations under the locking regime but also enriches the understanding of coherent phonons in multimode regimes, opening new avenues for optomechanical applications in signal processing.
Spatiotemporal dissipation dynamics: route to high beam quality and high peak power spatiotemporal mode-locked fiber lasers
Authors: Fu Guohao , Li Yuhang , Xiao Qirong , Li Dan , Gong Mali , Liu Qiang , Wabnitz Stefan , Yan Ping
Published: July 2024

Spatiotemporal mode-locking (STML) opens a new avenue for implementing high-energy, high-peak-power mode-locked fiber oscillators. However, their inferior beam quality is a fundamental issue that restricts their use. Here, spatiotemporal dissipation involving the quenching and reabsorption effects of multimode Erbium-doped fiber is proposed for beam quality enhancement of STML fiber lasers. The spatiotemporal dissipation provides spatiotemporal intensity-dependent losses to modal pulses for obtaining high beam quality, without needing the same rigorous conditions as Kerr beam self-cleaning (BSC) does. Together with Kerr BSC, the spatiotemporal dissipation BSC is utilized to achieve a high energy high-peak-power STML fiber laser operating at 1.5 µm region with high beam quality. Solitons with an energy of 6.7 nJ (the intracavity energy and peak power are 25.6 nJ and >52.8 kW), pulse duration of <489 fs, and beam quality with M²x/M²y=1.23/1.20 are obtained. To the best of our knowledge, it is a record peak power of 1.5 µm band soliton fiber laser reported so far. Additionally, broad-duration dissipative soliton resonance pulses with M²x/M²y=1.12/1.18, and noiselike pulses with M²x/M²y=1.04/1.13 are shown to prove the universality of the BSC method. This paper provides new insights for designing high-performance STML fiber lasers and for understanding the spatiotemporal dissipation dynamics.
Evaluating the cost and operational context for national human papillomavirus (HPV) vaccine delivery in three regions of Ethiopia
Authors: Mvundura Mercy , Bayeh Amare , Zelalem Meseret , Lakew Yohannes , Dhufera Adugna , Dagnew Belayneh , Slavkovsky Rose , Lamontagne D. Scott
Published: July 2024

Cervical cancer is the second leading cause of cancer deaths among women in Ethiopia. Human papillomavirus (HPV) vaccination is a primary prevention method for cervical cancer and was introduced in Ethiopia in 2018. We conducted a cross-sectional, mixed-methods study to understand the operational context for the HPV vaccination program and the associated costs in three regions of Ethiopia. Operations research provided insights on the frequency and intensity with which HPV vaccination program activities were done, focusing on activities conducted to vaccinate the cohort receiving its first dose in October 2019 and second dose in January 2021. Microcosting was used to estimate the costs to the health system for these activities. Data collection using structured questionnaires was done at 60 health facilities, 17 woredas, and 9 zones/sub-cities that were randomly selected from three purposively selected regions and the national level. Financial costs (monetary outlays) and economic costs (financial costs plus opportunity costs of resource use) were estimated in 2019 US$. Health facilities delivered an average of 411 HPV vaccine doses during the reference period, ranging from a mean of 86 to 606 across the three regions. Aggregated across all levels of the health system, the estimated financial cost per dose across the pooled sample was $2.23, and the economic cost per dose was $7.19, excluding the cost of vaccines and supplies. There were regional variations in these estimates, with mean financial cost per dose ranging from $1.17 to $7.18 and mean economic cost per dose ranging from $5.80 to $18.13 across the three regions. Regional variations exist in the service volume, frequency, and intensity of conducting HPV vaccination activities, as reflected in the estimated costs of delivery. Data generated from this study can be used to inform program planning and budgeting, taking into account regional variations, for effective utilization of resources.
Design and expression of a chimeric recombinant antigen (SsIR-Ss1a) for the serodiagnosis of human strongyloidiasis: Evaluation of performance, sensitivity, and specificity
Authors: Omidian Mostafa , Mostafavi-Pour Zohreh , Asadi Marzieh , Sharifdini Meysam , Nezafat Navid , Pouryousef Ali , Savardashtaki Amir , Taheri-Anganeh Mortaza , Mikaeili Fattaneh , Sarkari Bahador
Published: July 2024

Background

The sensitivity of parasitological and molecular methods is unsatisfactory for the diagnosis of strongyloidiasis, and serological techniques are remaining as the most effective diagnostic approach. The present study aimed to design and produce a chimeric recombinant antigen from Strongyloides stercoralis immunoreactive antigen (SsIR) and Ss1a antigens, using immune-informatics approaches, and evaluated its diagnostic performance in an ELISA system for the diagnosis of human strongyloidiasis.

Methodology/Principal findings

The coding sequences for SsIR and Ss1a were selected from GenBank and were gene-optimized. Using bioinformatics analysis, the regions with the highest antigenicity that did not overlap with other parasite antigens were selected. The chimeric recombinant antigen SsIR- Ss1a, was constructed. The solubility and physicochemical properties of the designed construct were analyzed and its tertiary structures were built and evaluated. The construct was expressed into the pET-23a (+) expression vector and the optimized DNA sequences of SsIR-Ss1a (873 bp) were cloned into competent E. coli DH5α cells. Diagnostic performances of the produced recombinant antigen, along with a commercial kit were evaluated in an indirect ELISA system, using a panel of sera from strongyloidiasis patients and controls.

The physicochemical and bioinformatics evaluations revealed that the designed chimeric construct is soluble, has a molecular with of 35 KDa, and is antigenic. Western blotting confirmed the immunoreactivity of the produced chimeric recombinant antigen with the sera of strongyloidiasis patients. The sensitivity and specificity of the indirect ELISA system, using the produced SsIR-Ss1a chimeric antigen, were found to be 93.94% (95% CI, 0.803 to 0.989) and 97.22% (95% CI, 0.921 to 0.992) respectively.

Conclusions/Significance

The preliminary findings of this study suggest that the produced SsIR-Ss1a chimeric antigen shows promise in the diagnosis of human strongyloidiasis. However, these results are based on a limited panel of samples, and further research with a larger sample size is necessary to confirm its accuracy. The construct has potential as an antigen in the ELISA system for the serological diagnosis of this neglected parasitic infection, but additional validation is required.
A comprehensive in vitro characterization of non-crosslinked, diverse tissue-derived collagen-based membranes intended for assisting bone regeneration
Authors: Barrino Federico , Vassallo Valentina , Cammarota Marcella , Lepore Maria , Portaccio Marianna , Schiraldi Chiara , La Gatta Annalisa
Published: July 2024

Collagen-based membranes are class III-medical devices widely used in dental surgical procedures to favour bone regeneration. Here, we aimed to provide biophysical and biochemical data on this type of devices to support their optimal use and design/manufacturing. To the purpose, four commercial, non-crosslinked collagen-based-membranes, obtained from various sources (equine tendon, pericardium or cortical bone tissues, and porcine skin), were characterized in vitro. The main chemical, biophysical and biochemical properties, that have significant clinical implications, were evaluated. Membranes showed similar chemical features. They greatly differed in morphology as well as in porosity and density and showed a diverse ranking in relation to these latter two parameters. Samples highly hydrated in physiological medium (swelling-ratio values in the 2.5–6.0 range) and, for some membranes, an anisotropic expansion during hydration was, for the first time, highlighted. Rheological analyses revealed great differences in deformability (150-1500kPa G’) also alerting about the marked variation in membrane mechanical behaviour upon hydration. Samples proved diverse sensitivity to collagenase, with the cortical-derived membrane showing the highest stability. Biological studies, using human-bone-derived cells, supported sample ability to allow cell proliferation and to prompt bone regeneration, while no relevant differences among membranes were recorded. Prediction of relative performance based on the findings was discussed. Overall, results represent a first wide panel of chemical/biophysical/biochemical data on collagen-based-membranes that 1) enhances our knowledge of these products, 2) aids their optimal use by providing clinicians with scientific basis for selecting products based on the specific clinical situation and 3) represents a valuable reference for optimizing their manufacturing.
Development of innovative alkali activated paste reinforced with polyethylene fibers for concrete crack repair
Authors: Iqbal Munir , Ashraf Muhammad , Nazar Sohaib , Alkhattabi Loai , Alam Jihad , Alabduljabbar Hisham , Khan Zahoor
Published: July 2024

Concrete structures are susceptible to cracking, which can compromise their integrity and durability. Repairing them with ordinary Portland cement (OPC) paste causes shrinkage cracks to appear in the repaired surface. Alkali-activated binders offer a promising solution for repairing such cracks. This study aims to develop an alkali-activated paste (AAP) and investigate its effectiveness in repairing concrete cracks. AAPs, featuring varying percentages (0.5%, 0.75%, 1%, 1.25%, 1.5%, and 1.75%) of polyethylene (PE) fibers, are found to exhibit characteristics such as strain hardening, multiple plane cracking in tension and flexure tests, and stress-strain softening in compression tests. AAP without PE fibers experienced catastrophic failure in tension and flexure, preventing the determination of its stress-strain relationship. Notably, AAPs with 1.25% PE fibers demonstrated the highest tensile and flexural strength, exceeding that of 0.5% PE fiber reinforced AAP by 100% in tension and 70% in flexure. While 1% PE fibers resulted in the highest compressive strength, surpassing AAP without fibers by 17%. To evaluate the repair performance of AAP, OPC cubes were cast with pre-formed cracks. These cracks were induced by placing steel plates during casting and were designed to be full and half-length with widths of 1.5 mm and 3 mm. AAP both with and without PE fibers led to a substantial improvement in compressive strength, reducing the initial strength loss of 30%-50% before repair to a diminished range of 2%-20% post-repair. The impact of PE fiber content on the compressive strength of repaired OPC cube is marginal, providing more flexibility in using AAP with any fiber percentage while still achieving effective concrete crack repair. Considering economic and environmental factors, along with observed mechanical enhancements, AAPs show promising potential for widespread use in concrete repair and related applications, contributing valuable insights to the field of sustainable construction materials.
Effects of precise cardio sounds on the success rate of phonocardiography
Authors: Kim Youngsin , Moon Mihyung , Moon Seokwhwan , Moon Wonkyu
Published: July 2024

This work investigates whether inclusion of the low-frequency components of heart sounds can increase the accuracy, sensitivity and specificity of diagnosis of cardiovascular disorders. We standardized the measurement method to minimize changes in signal characteristics. We used the Continuous Wavelet Transform to analyze changing frequency characteristics over time and to allocate frequencies appropriately between the low-frequency and audible frequency bands. We used a Convolutional Neural Network (CNN) and deep-learning (DL) for image classification, and a CNN equipped with long short-term memory to enable sequential feature extraction. The accuracy of the learning model was validated using the PhysioNet 2016 CinC dataset, then we used our collected dataset to show that incorporating low-frequency components in the dataset increased the DL model’s accuracy by 2% and sensitivity by 4%. Furthermore, the LSTM layer was 0.8% more accurate than the dense layer.