bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-Mode Amplification in a Multimode Fiber Regenerative Amplifier
Authors: Haig Henry , Bender Nicholas , Eisenberg Yishai , Wise Frank W.
Published: September 2024

We show that regenerative amplification enables a femtosecond fiber amplifier with an unprecedented combination of features: single-mode operation (M2≤ 1.3) despite multimode (100 μm) fiber, high-gain (> 55 dB), and high pulse energy (> 50 μJ).
Generation of high-order femtosecond vortices up to the 10th order from a powerful mode-locked Hermite-Gaussian laser
Authors: Liu Hongyu , Yan Lisong , Chen Hongshan , Liu Xin , Liu Heyan , Wang Qing , Zhang Jinwei
Published: September 2024

We present a mode-locked Hermite-Gaussian Yb:KGW laser oscillator. The
average powers and pulse durations of vortex pulses up to 10th via
astigmatic mode conversion are several hundred milliwatts and less
than 500 fs, respectively.
Nanodiamonds With Group IV Defects Coupled to Fabry-Perot Resonators
Authors: Berghaus Robert , Bayer Gregor , Sachero Selene , Feuchtmayr Florian , Agafonov Viatcheslav , Kubanek Alexander
Published: September 2024

Using color center in diamond (e.g. silicon vacancy) coupled to an open Fabry-Perot cavity, we present an efficient spin-photon interface. We demonstrate optical coherent driving of a silicon vacancy transition and Purcell enhancement.
High-Q photonic crystals cavities in visible wavelength using a thin film diamond
Authors: Ding Sophie W. , Haas Michael , Guo Xinghan , Kuruma Kazuhiro , Jin Chang , Awschalom David D. , Delegan Nazar , Heremans F. Joseph , High Alex , Loncar Marko
Published: September 2024

We report photonic crystal cavities fabricated in a thin film diamond, featuring quality factors as high as ~2 x105 in visible wavelengths, and we demonstrate coupling between the cavity mode and a single silicon-vacancy center.
MMW/Sub-THz/THz Signal through Bi-Directional Fiber-Optical/RF Wireless Transmission Employing Two Cascaded RSOAs
Authors: Xu Yan-Zhen , Chen Wei-Xiang , Lin Chih-Hong , Jin Jia-Lian , Wu Tsai-Man , Lu Hai-Han
Published: September 2024

MMW/Sub-THz/THz signals through bi-directional fiber-optical/RF wireless transmission with two cascaded RSOAs is implemented. By cascading RSOA, the downstream data are virtually eliminated for upstream. It shows potential for MMW/sub-THz/THz signals through bi-directional fiber-optical/RF wireless transmission.
Intact-skull cranial windows for widefield optical imaging in juvenile mice: complications and consequences
Authors: Adepoju Temilola E. , Fisher Hayden B. , Winston Chloe , White Brian R.
Published: September 2024

Functional neuroimaging with widefield optical imaging (WOI) is potentially useful for studying developmental disorders in juvenile mice. However, WOI requires an intact-skull cranial window, and the effects of such windows on young mice are unknown. We performed intact-skull cranial window placement on mice as young as P7 to study the effects of chronic placement. Cranial windows placed at young ages (P7 and P10) were not longitudinally stable, resulting in significant attrition. Windows placed at ages P14 or less resulted in significant impairment to skull growth, which in turn caused artifacts in resting-state functional connectivity analysis. Longitudinal cranial windows should likely be avoided under P30.
Dynamics of circular Airy beams with spatial and frequency modulations in a cubic-quintic nonlinear fractional Schrödinger equation: from linear to soliton control
Authors: Lei Tong , Zou Min , Tan Chao , Liang Yong , Liu Mingwei
Published: September 2024

The transmission dynamics of a circular Airy beam (CAB) with quadratic phase modulation (QPM) and cross-phase modulation (XPM) in the cubic-quintic nonlinear fractional Schrödinger equation (FSE) optical system is investigated. In the linear case, the energy distribution of the beam is affected by XPM and the focusing position of the beam is influenced by QPM. CAB undergoes splitting and its intensity is shifted as the absolute value of the XPM coefficient (|c|) increases. When XPM coefficients are opposite to each other, CABs are transmitted in opposite states in space. The degree of interference between beams gradually enhances with the increase of the XPM coefficient, leading to the formation of interference resembling water ripples. In the nonlinear regime, different results (evolving into solitons or undergoing diffraction transmission) are observed in CABs based on cubic-quintic nonlinear combination modes. Furthermore, nonlinear combination modes that can generate solitons and changes in solitons under actions of XPM and QPM are studied in detail. The distribution of solitons can be altered by positive or negative XPM, and solitons exist when QPM coefficients are within a certain range. The spacing and number of solitons can be modified by adjusting the magnitude of the QPM coefficient. The research shows that the control for solitons (number, distribution, and propagation) can be achieved through flexible selection of cubic-quintic nonlinear combination modes and parameter optimization (XPM coefficient, QPM coefficient, Lévy index).
Ultra-precision fabrication technology based on fusion figuring of surface height and slope profile for EUVL objective lenses
Authors: Gao Qing , Wang Shanshan , Zhang Nansheng , Shi Feng , Qiao Shuo , Hao Qun
Published: September 2024

The manufacturing requirements for extreme ultraviolet lithography (EUVL) projection lenses are highly stringent, demanding ultra-precise control over surface height and slope profile to achieve optimal imaging quality. Nevertheless, the current technology lacks the explicit capability to control the two-dimensional (2D) surface slope of optics. Focusing on the ultra-precision machining technology based on slope profile, a partial derivative exchange decoupling (PDED) method is proposed to approximately calculate the vector removal coupling problem within the 2D slope-based figuring (SF) model, specifically addressing the interplay between the slope removal function and the slope error. Furthermore, the fusion figuring (FF) model accomplishing the dual monitoring of both surface height accuracy and slope profile accuracy is proposed innovatively. Through simulation experiments, the modification results of the fusion, slope-based, and height-based figuring (HF) models are systematically compared and analyzed, demonstrating the effectiveness and superiority of the fusion figuring model. In actual manufacturing experiments, the FF model improves RMS convergence for slope errors by over 20% and for height errors by nearly 10% compared to the HF model. The research results successfully achieve a notable level of convergence in optics machining and provide a new approach with ultra-precision and stability for the fabrication of complex optics requiring precise control of both surface and slope accuracy.
RF crosstalk mitigation via floating shields in parallel silicon traveling-wave modulators
Authors: Mohammadi Abdolkhalegh , Rusch Leslie A. , Shi Wei
Published: September 2024

High-density integration of electro-optic (E-O) elements in photonic integrated circuits (PICs) offers compact, low-cost high-capacity transceiver modules. Tighter component spacing increases compactness, but leads to crosstalk that can degrade performance. We investigate and characterize the crosstalk between silicon traveling-wave Mach-Zehnder modulators (TW-MZMs) laid out in parallel in PICs. We propose the use of floating shield strips to reduce E-O crosstalk between these TW-MZMs. We show via simulation and experiment that these strips can increase shoreline bandwidth density by nearly 50%. The improvement in E-O crosstalk covers frequencies as high as 60 GHz.
CGH calculation algorithm for expressing reflection on a curved mirror surface
Authors: Arai Hiroya , Ono Kodai , Sakamoto Yuji
Published: September 2024

Rendering techniques are important in computer-generated holograms (CGHs) for expressing various types of holo-realistic 3D images. Rendering techniques such as hidden surface removal and reflection by a planar mirror have been proposed thus far, but reflection on a curved mirror surface has yet to be achieved. In this study, we propose a calculation algorithm that can express the reflection of the surrounding environment on a mirror surface defined as a Bézier surface. The results of optical experiments demonstrate that the proposed algorithm enables reflection on such a mirror surface and that the calculation can be accelerated by using a graphics processing unit (GPU).
56 Gbps externally modulated widely tunable lasers with SOA boosters heterogeneously integrated on silicon
Authors: Souleiman A. , Neel D. , Besancon C. , Vaissiere N. , Malhouitre S. , Hassan K. , Decobert J. , Bitauld D. , Benkelfat B. , Merghem K. , Ramirez J. M.
Published: September 2024

We demonstrate externally modulated widely tunable lasers co-integrated with semiconductor optical amplifiers (SOAs) heterogeneously integrated on silicon. The widely tunable laser enables continuous single-mode operation over a tuning range of approximately 40 nm, with a side-mode suppression ratio (SMSR) of at least 50 dB and an average waveguide-coupled optical power of 5 mW. The integrated electro-absorption modulator (EAM) exhibits an extinction ratio (ER) of 16 dB when reversed biased at -2 V. The bit-error-rate (BER) measurements conducted across the available optical bandwidth (15 nm) showcase error-free transmission at 32 Gbps using non-return-to-zero (NRZ) signals for the majority of wavelengths in a back-to-back (B2B) configuration. Additionally, transmission measurements over distances of up to 10 km through a standard single-mode fiber (SSMF) have been successfully demonstrated. Dynamic extinction ratio (DER) values exceeding 4.5 dB are achieved for all wavelengths. Open-eye diagrams were measured up to 56 Gbps. These results demonstrate that this compact mono-epitaxial externally modulated tunable laser with integrated optical amplification can be a cost-effective transmitter solution for dense wavelength division multiplexing (DWDM) metropolitan and access networks.
Modulation format identification in elastic optical networks using integrated photonic reservoir computing and untrained K-nearest neighbors algorithm
Authors: Li Quan , Pei Li , Bai Bing , Wang Jianshuai , Bai Bowen , Zuo Xiaoyan , Sui Juan , Dong Fei
Published: September 2024

In the next generation of Elastic Optical Networks, various modulation formats exhibit varying degrees of sensitivity to channel impairments during transmission. To adopt appropriate channel equalization schemes at the receiver, it is essential to perform modulation format identification prior to the receiver, followed by the adjustment of receiver parameters and types based on the recognition results. A system based on a 52-node integrated photonic reservoir chip and untrained K-nearest neighbors (KNN) algorithm is proposed for the recognition of OOK, PAM4, QPSK, and BPSK modulation formats in optical channel transmission. Its performance is validated across optical signal-to-noise ratios ranging from 8 to 23 dB, taking into account the dispersion damage of 20 km single-mode fiber transmission. In all tested scenarios, the recognition accuracy consistently surpasses 96.25%, showcasing a 14.93% improvement over prior works and an 82.81% enhancement over traditional algorithmic methods under identical conditions. The study explores the impact of different waveguide delay amounts, random phases, and algorithm K values on recognition accuracy.
Broadband planar electromagnetic hyperlens with uniform magnification in air
Authors: Sun Ran , Sun Fei , Chen Hanchuan , Liu Yichao , Wang Qi
Published: September 2024

A planar hyperlens, capable of creating sub-wavelength imaging for broadband electromagnetic waves, is designed based on an electromagnetic null medium. Subsequently, a scheme for the implementation of the proposed hyperlens is given by using well-designed flexural metal plates, which function as the reduced electromagnetic null medium for TM-polarized microwaves. Both simulated and measured results verify that the hyperlens designed with flexural metal plates can achieve super-resolution imaging for microwave at operating wavelength (λ0 = 3 cm) with a resolution of 0.25λ0 and a uniform magnification of about 5. Moreover, the designed hyperlens ensure that both the object and image surfaces are planes and simultaneously provides a uniform magnification for objects in different positions. Additionally, the proposed hyperlens offer broadband super-resolution imaging capabilities, achieving good super-resolution imaging effects for microwave frequencies ranging from 8.3 to 11.3 GHz. The proposed hyperlens may find applications in high precision imaging, detection, and sensing.
Non-invasive characterization of cascaded SOAs on InP-based photonic integrated circuits
Authors: Wang Xudong , Shi Bin , Liu Lin , Feyisa Desalegn Wolde , Liu Juanxiu , Zhang Shangjian , Ye Yutang , Liu Yong , Stabile Ripalta
Published: September 2024

Semiconductor optical amplifiers (SOAs) are widely used as active elements in optical switching networks for their features of loss compensation and fast reconfiguration time. To optimize the SOA chain operation, it is essential to know the gain response of each SOA. However, the performance of the individual SOA in an on-chip network is challenging to characterize without additional splitters, which increases path insertion losses and, therefore, power consumption. In this work, to address these issues through a feasible and non-disruptive solution, a non-invasive pre-monitoring for N-cascaded SOAs on InP chips is proposed to assess the SOA gain and path losses between cascaded SOAs. This solution utilizes each SOA as both an optical amplifier (OA) and photodetector (PD), characterized by both light propagation directions, forward and backward. We experimentally demonstrate the non-invasive characterization method on a photonic integrated chip (PIC) containing 3-cascaded SOAs, which are part of a photonic integrated SOA-based optical neural network chip. Experimental results show that both losses between SOA and noise can be retrieved and used to obtain the SOA gain curves. The obtained SOA curves are in good agreement with the reference SOA measurements with errors <1.0 dB in gain and <1.5 dB in noise response. These results pave the way to automated non-invasive screening of N-cascaded SOAs in large-scale and packaged PICs.
Research on the simulation method of a BP neural network PID control for stellar spectrum
Authors: Yun Zhikun , Zhang Yu , Liu Qiang , Ren Taiyang , Zhao Bin , Xu Da , Yang Songzhou , Ren Dianwu , Yang Junjie , Mo Xiaoxu , Zhang Jian , Zhang GuoYu
Published: September 2024

This study investigated the multiple correlations among spectral simulation units based on digital micromirror device (DMD) spectral simulation, which leads to the problem that conventional spectral simulation methods such as PID control exhibit a low fitting accuracy or long fitting time in the spectral simulation of various targets. In this paper, a method of stellar spectrum simulation based on back propagation neural network-based PID (BP-PID) control is proposed to achieve high efficiency and high precision simulation of various spectral targets. The topology of the BP neural network was constructed based on the spectral modulation model of a DMD stellar spectrum simulation system, and the algorithm of the BP-PID control was designed. Finally, an experimental platform was built to verify the performance and spectral simulation accuracy of the BP-PID control algorithm. The results show that the overshoot and response time of the BP-PID control algorithm decreased by 79.01% and 30%, respectively compared with those of the PID control algorithm. The maximum spectral simulation accuracies of 2000K, 7000K, and 12000K color temperature increased by a factor of 2.311, 1.871, and 2.254, respectively, and the standard deviations of the spectral simulation error decreased by 56%, 41%, and 54%, respectively. In the range of 2000-12000K color temperature, the spectral simulation error of the BP-PID control algorithm is better than ±3.495%, and the standard deviation of the spectral simulation error is between 1.8255 and 2.2358. The proposed method can improve the spectral simulation accuracy and simulation efficiency of a star simulator, reduce the magnitude and spectrum calibration errors caused by the differential response, improve the star feature recognition accuracy of the orbiting star sensor, and hence, provide a theoretical and technical basis for the development of high-precision star sensors.
CdSe-based quantum dots assisted deep ultraviolet light detection and visualization
Authors: Xiao Hua , Liu Mingxin , Zhang Jiarui , Ye Xianglong , Luo Yunshu , Lin Yue , Wang Lei , Sun Caiming
Published: September 2024

To clarify the positive effect of the down-conversion process for ultraviolet (UV) and deep ultraviolet (DUV) light detection and visualization, we choose, synthesize, and characterize a spectrum of direct-bandgap CdSe-based colloidal quantum dot (QD) solvents and color-conversion layers (CCLs) across blue, green, yellow, orange, and red hues. Their optical absorption, emission, and response speeds under various UV and DUV wavelength of 280 nm, 372 nm, and 405 nm are evaluated. The blue QD CCL demonstrated the highest quantum yield up to 0.68. By integrating this blue QD CCL directly onto a silicon-based photodiode, the responded optical power to 280-nm DUV light is significantly enhanced by 27 times; this data decreases slightly to 23 times when using orange QDs, due to the comparatively lower quantum yield. For the optimal result in a communication system, the orange QDs help exhibit the highest response of 520 mV when stimulated with 372-nm UV light, compared with a substantial improvement over the original response of 120 mV. This enhancement makes the orange QDs significantly reduces the BER, especially at data rates below 70 Mb/s, due to the stronger response of the avalanche photodiode (APD) at 600 nm. Furthermore, to demonstrate the potential application of QDs for patterning and visualization, we have also produced CdSe-based QDs through inkjet printing, showcasing their printability, high stability in air, and pure color emission under DUV illumination. These results underscore the significant potential of CdSe-based QDs for full-color anti-counterfeiting solutions and their integration into flexible, printable wearables for a variety of visualization and DUV detection applications.
Quasi-BIC supported flexible terahertz metamaterial sensor for curvature measurement
Authors: Dai Zijie , Yan Can , Ye Yunxia , Chen Mingyang , Liang Ying , Li Jitao
Published: September 2024

High-Q resonances excited by bound states in a continuum (BIC) in metamaterial have sparked increasing research interests for its prospective applications in sensing, lasing, and nonlinear optical devices. This paper introduces a quasi-BIC supported flexible terahertz (THz) metamaterial sensor for curvature measurement. The symmetry-protected BICs based on metallic rectangle structures on a thin flexible polyimide substrate are designed. After introducing defect perturbations along the x and y directions into the metallic rectangle, two observable quasi-BICs would be excited by x and y-polarized THz waves, respectively. Moreover, an experimental demonstration of the curvature sensing performance is conducted by monitoring spectral evolution in response to the bending BIC metallic metamaterial. The measured results indicate that the resonant transmission amplitude is sensitive to variations in the applied curvatures. The flexible, easy manufacturing, and highly-sensitive quasi-BIC micro structured metamaterial sensor paves a new way toward developing sensitive and wearable BICs-related optoelectronic devices.
Encryption-decryption scheme in a single-pixel system based on polarization and Laguerre-Gaussian mode modulation
Authors: Wang Luyi , Zeng Jie , Wang Guangyao , Chen Zhenhua , Hu Wei , Zhang Yong
Published: September 2024

Optical cryptosystems are crucial for ensuring the security of optical information transmission and storage. The indirect measurement mechanism of single-pixel imaging (SPI) offers a feasible implementation channel for optical cryptosystems. Illumination patterns are encryption keys projected onto the plaintext object, while the intensity collected by the single-pixel detector forms the ciphertext. However, the variations in the object's angular position during SPI measurement generally introduce certain inaccuracies in image reconstruction. And due to SPI's input-output linear mapping relationship, the plaintext is vulnerable to exposure. This proposes an encryption-decryption scheme in a single-pixel system based on polarization and Laguerre-Gaussian (LG) mode modulation. The inherent circular symmetry of LG mode makes the angular position of the object information that can be encrypted, while the intrinsic properties of the object can be represented by polarization. Our system characterizes various polarization parameters of samples serving as reliable plaintext with an error of less than 4.2%, including depolarization, diattenuation, and retardance. For encryption demonstration, LG modes are randomly divided into 5 groups, corresponding to an object at different rotational states. This, combined with 16 polarization modulations, constructs pattern-angle-polarization joint keys, enabling high-security encryption as well as high-fidelity decryption of the mask image, optical axis orientation, and retardance of the test sample. Experimental results demonstrate the effectiveness of our scheme in enhancing the security and information complexity of optical cryptography, offering valuable insights for optical communication and quantum information security.
Photonic skyrmion spin textures on meta-surface with the impact of loss and geometry
Authors: Lin Min , Li Zhenli , Yang Aiping , Du Luping , Yuan Xiaocong
Published: September 2024

Photonic skyrmions characterized by topological nontrivial electromagnetic textures have triggered enormous interest, exhibiting promising applications in optical information storage and precision metrology. The skyrmion generation on meta-surface is important for further developments of the skyrmion-based applications; however, it has received limited attention, with a particular lack of investigation into both intrinsic loss and geometry, which are crucial factors. Here, we demonstrate a photonic skyrmion spin lattice on a well-designed metallic nanohole array, examining the influence of inherent loss and geometry of meta-surface. In consideration of these factors, we show the broadened excitation wavelength tolerance for the photonic skyrmion spin lattices, which are also found to be robust against the inherent loss and wave-vector mismatch to a certain degree. This work provides new insights into the underlying mechanisms of the topological spin textures, as well as in developing applications in optical sensing and high-resolution imaging.
Fast-scanning speed single-photon counting LiDAR based on front focal length modulation
Authors: Ye Yiingjie , Kong Deyao , Xia Maopeng , Zhai Wenchao , Zheng Xiaobing , Kang Qing
Published: September 2024

This Letter presents a method for fast-scanning speed LiDAR based on front focal length modulation in the transmitter, which compensates for the influence of the laser divergence angle on the scanning speed at close range of the long-range LiDAR. According to the thin lens equation for Gaussian beams, the laser divergence angle is affected by the distance from the lens to the object (the waist of the laser beam). The scanning speed of the LiDAR is correlated to the laser divergence angle during LiDAR operation, and the scanning speed can be improved by expanding the laser divergence angle by enlarging the front focal length of the transmitter. Through experimental analysis, the laser dispersion angle modulation of LiDAR can improve the scanning speed under the premise of guaranteeing the target detection performance in close-range detection.
Bayesian-neural-network-based strain estimation approach for optical coherence elastography
Authors: Bai Yulei , Zhang Kangyang , Mo Rui , Ni Zihao , He Zhaoshui , Xie Shengli , Dong Bo
Published: September 2024

Strain estimation is critical for quantitative elastography in
quasi-static phase-sensitive optical coherence elastography (PhS-OCE).
Deep-learning methods have achieved exceptional performance in
estimating high-quality strain distributions. However, they cannot
often assess their predictive accuracy and reliability rigorously. To
navigate these challenges, a Bayesian-neural-network (BNN)-based
strain estimation is proposed. The method can provide the uncertainty
distribution of the results beyond achieving high-quality strain
estimation. Such an uncertainty distribution can assess the
reliability of the strain results. Moreover, the uncertainty degree
can function as an indicator for compensating for phase decorrelation
and thus significantly enhancing the SNR and dynamic range of PhS-OCE.
Thermal and three-point bending deformation experiments validated that
the predicted uncertainty distribution can effectively address phase
decorrelation and allow for a more comprehensive understanding of the
estimated strain results.
MVST: Identifying spatial domains of spatial transcriptomes from multiple views using multi-view graph convolutional networks
Authors: Duan Hao , Zhang Qingchen , Cui Feifei , Zou Quan , Zhang Zilong
Published: September 2024

Spatial transcriptome technology can parse transcriptomic data at the spatial level to detect high-throughput gene expression and preserve information regarding the spatial structure of tissues. Identifying spatial domains, that is identifying regions with similarities in gene expression and histology, is the most basic and critical aspect of spatial transcriptome data analysis. Most current methods identify spatial domains only through a single view, which may obscure certain important information and thus fail to make full use of the information embedded in spatial transcriptome data. Therefore, we propose an unsupervised clustering framework based on multiview graph convolutional networks (MVST) to achieve accurate spatial domain recognition by the learning graph embedding features of neighborhood graphs constructed from gene expression information, spatial location information, and histopathological image information through multiview graph convolutional networks. By exploring spatial transcriptomes from multiple views, MVST enables data from all parts of the spatial transcriptome to be comprehensively and fully utilized to obtain more accurate spatial expression patterns. We verified the effectiveness of MVST on real spatial transcriptome datasets, the robustness of MVST on some simulated datasets, and the reasonableness of the framework structure of MVST in ablation experiments, and from the experimental results, it is clear that MVST can achieve a more accurate spatial domain identification compared with the current more advanced methods. In conclusion, MVST is a powerful tool for spatial transcriptome research with improved spatial domain recognition.
Anaemia at 36 weeks of pregnancy: Prevalence and determinants among antenatal women attending peri-urban facilities in a developing country, Ghana
Authors: Adjei-Gyamfi Silas , Asirifi Abigail , Peprah Wisdom , Abbey Delphina Aneley , Hamenoo Kwadzo Wisdom , Zakaria Mary Sakina , Mohammed Osman , Aryee Paul Armah
Published: September 2024

Anaemia as a critical health condition greatly upsurges the risk of pregnancy complications leading to preventable maternal mortalities and long-term morbidities. Therefore, identifying anaemia-associated factors is vital for planning relevant interventions in resource-constrained regions in Sahelian Africa. This study aimed to assess the prevalence and determinants of anaemia at 36 weeks of pregnancy among antenatal women in a peri-urban municipality of Ghana. A retrospective cross-sectional study was conducted among antenatal women from five different health facilities in Savelugu Municipality. Using antenatal register as the sampling frame, 422 participants were sampled. Data were collected via antenatal records review and a structured questionnaire. Using STATA, binary logistic regression was performed to identify significantly associated factors of anaemia at 36 weeks of pregnancy, considering a significance level of α = 0.05. Prevalence of anaemia at 36 weeks was 45.3%. Low socioeconomic status (AOR = 1.78; 95%CI:1.10–2.90; p = 0.020), pre-pregnancy body mass index ≥ 25 kg/m2 (overweight or obesity) (AOR = 1.62; 95%CI:1.01–2.58; p = 0.041), non-intake of sulphadoxine-pyrimethamine drugs (AOR = 2.22; 95%:1.40–3.51; p = 0.001), and malaria infection (AOR = 3.14; 95%CI:1.66–5.93; p<0.001) were associated with increased odds of anaemia at 36 weeks of pregnancy. Anaemia remains a burden in peri-urban Northern Ghana. Given the observed correlates of anaemia, interventions should be focused on strengthening malaria preventive measures, poverty alleviation, and peri-conception nutrition programs to avert adverse pregnancy outcomes.
Prevention of congenital chagas disease by trypanocide treatment in women of reproductive age: A meta-analysis of observational studies
Authors: Moraes Francisco Cezar Aquino de , Souza Maria Eduarda Cavalcanti , Dal Moro Lucca , Donadon Isabelle Batista , da Silva Emanuele Rocha , de Souza Dilma do Socorro Moraes , Burbano Rommel Mario Rodríguez
Published: September 2024

Background

Maternal-foetal transmission of Chagas disease (CD) affects newborns worldwide. Although Benznidazole and Nifurtimox therapies are the standard treatments, their use during pregnancy is contra-indicated. The effectiveness of trypanocidal medications in preventing congenital Chagas Disease (cCD) in the offsprings of women diagnosed with CD was highly suggested by other studies.

Methods

We performed a systematic review and meta-analysis of studies evaluating the effectiveness of treatment for CD in women of childbearing age and reporting frequencies of cCD in their children. PubMed, Scopus, Web of Science, Cochrane Library, and LILACS databases were systematically searched. Statistical analysis was performed using Rstudio 4.2 using DerSimonian and Laird random-effects models. Heterogeneity was examined with the Cochran Q test and I2 statistics. A p-value of <0.05 was considered statistically significant.

Results

Six studies were included, comprising 744 children, of whom 286 (38.4%) were born from women previously treated with Benznidazole or Nifurtimox, trypanocidal agents. The primary outcome of the proportion of children who were seropositive for cCD, confirmed by serology, was signigicantly lower among women who were previously treated with no congenital transmission registered (OR 0.05; 95% Cl 0.01–0.27; p = 0.000432; I2 = 0%). In women previously treated with trypanocidal drugs, the pooled prevalence of cCD was 0.0% (95% Cl 0–0.91%; I2 = 0%), our meta-analysis confirms the excellent effectiveness of this treatment. The prevalence of adverse events in women previously treated with antitrypanocidal therapies was 14.01% (95% CI 1.87–26.14%; I2 = 80%), Benznidazole had a higher incidence of side effects than Nifurtimox (76% vs 24%).

Conclusion

The use of trypanocidal therapy in women at reproductive age with CD is an effective strategy for the prevention of cCD, with a complete elimination of congenital transmission of Trypanosoma cruzi in treated vs untreated infected women.
Isolation and characterization of genetic variants of Orthohantavirus hantanense from clinical cases of HFRS in Jiangxi Province, China
Authors: Liu Shiwen , Deng Zhishi , Li Jianxiong , Zou Long , Sun Xiuhui , Liu Xiaoqing , Shi Yong , Huang Shunqiang , Wu Yangbowen , Lei Jinhui , Liu Peipei , Zhang Pei , Xiong Ying , Long Zhong-er
Published: September 2024

Background

Hemorrhagic fever with renal syndrome (HFRS) is a severe public health problem in Jiangxi province, China. Previous studies reported genetic variants of Orthohantavirus hantanense (Hantaan virus, HTNV) in rodents in this area. However, the relationship between HTNV variants and human infection needs to be confirmed. This study aimed to identify the HTNV variants in patients and to understand the clinical characteristics of HFRS caused by these variants.

Methods

Samples were collected from hospitalized suspected cases of HFRS during the acute phase. HFRS cases were confirmed using quantitative real-time RT-PCR. Peripheral blood mononuclear cells (PBMC) from patients with HFRS were inoculated into Vero-E6 cells for viral isolation. The genomic sequences of HTNV from patients were obtained by amplicon-based next-generation sequencing. A retrospective analysis was conducted on the clinical characteristics of the patients.

Results

HTNV RNA was detected in 53 of 183 suspected HFRS patients. Thirteen HTNVs were isolated from 32 PBMCs of HFRS cases. Whole genome sequences of 14 HTNVs were obtained, including 13 isolates in cell culture from 13 patients, and one from plasma of the fatal case which was not isolated successfully in cell culture. Genetic analysis revealed that the HTNV sequence from the 14 patients showed significant variations in nucleotide and amino acid to the HTNV strains found in other areas. Fever (100%, 53/53), thrombocytopenia (100%, 53/53), increased serum aspartate aminotransferase (100%, 53/53), and increased lactate dehydrogenase (96.2%, 51/53) were the most common characteristics. Severe acute kidney injury was observed in 13.2% (7/53) of cases. Clinical symptoms, such as pain, petechiae, and gastrointestinal or respiratory symptoms were uncommon.

Conclusion

The HTNV genetic variants cause human infections in Jiangxi. The clinical symptoms of HFRS caused by the HTNV genetic variant during the acute phase are atypical. In addition to renal dysfunction, attention should be paid to the common liver injuries caused by these genetic variants.
Structural and biochemical investigation into stable FGF2 mutants with novel mutation sites and hydrophobic replacements for surface-exposed cysteines
Authors: An Young Jun , Jung Ye-Eun , Lee Kyeong Won , Kaushal Prashant , Ko In Young , Shin Seung Min , Ji Sangho , Yu Wookyung , Lee Cheolju , Lee Won-Kyu , Cha Kiweon , Lee Jung-Hyun , Cha Sun-Shin , Yim Hyung-Soon
Published: September 2024

Fibroblast growth factor 2 (FGF2) is an attractive biomaterial for pharmaceuticals and functional cosmetics. To improve the thermo-stability of FGF2, we designed two mutants harboring four-point mutations: FGF2-M1 (D28E/C78L/C96I/S137P) and FGF2-M2 (D28E/C78I/C96I/S137P) through bioinformatics, molecular thermodynamics, and molecular modeling. The D28E mutation reduced fragmentation of the FGF2 wild type during preparation, and the substitution of a whale-specific amino acid, S137P, enhanced the thermal stability of FGF2. Surface-exposed cysteines that participate in oligomerization through intermolecular disulfide bond formation were substituted with hydrophobic residues (C78L/C78I and C96I) using the in silico method. High-resolution crystal structures revealed at the atomic level that the introduction of mutations stabilizes each local region by forming more favorable interactions with neighboring residues. In particular, P137 forms CH-π interactions with the side chain indole ring of W123, which seems to stabilize a β-hairpin structure, containing a heparin-binding site of FGF2. Compared to the wild type, both FGF2-M1 and FGF2-M2 maintained greater solubility after a week at 45 °C, with their Tm values rising by ~ 5 °C. Furthermore, the duration for FGF2-M1 and FGF2-M2 to reach 50% residual activity at 45 °C extended to 8.8- and 8.2-fold longer, respectively, than that of the wild type. Interestingly, the hydrophobic substitution of surface-exposed cysteine in both FGF2 mutants makes them more resistant to proteolytic cleavage by trypsin, subtilisin, proteinase K, and actinase than the wild type and the Cys → Ser substitution. The hydrophobic replacements can influence protease resistance as well as oligomerization and thermal stability. It is notable that hydrophobic substitutions of surface-exposed cysteines, as well as D28E and S137P of the FGF2 mutants, were designed through various approaches with structural implications. Therefore, the engineering strategies and structural insights adopted in this study could be applied to improve the stability of other proteins.
The effect of excessive trabeculation on cardiac rotation—A multimodal imaging study
Authors: Grebur Kinga , Mester Balázs , Horváth Márton , Farkas-Sütő Kristóf , Gregor Zsófia , Kiss Anna Réka , Tóth Attila , Kovács Attila , Fábián Alexandra , Lakatos Bálint Károly , Fekete Bálint András , Csonka Katalin , Bödör Csaba , Merkely Béla , Vágó Hajnalka , Szűcs Andrea
Published: September 2024

Background

Cardiac rotational parameters in primary symptomatic left ventricular noncompaction (LVNC) with preserved left ventricular ejection fraction (LVEF) are not well understood. We aimed to analyze cardiac rotation measured with cardiac magnetic resonance feature-tracking (CMR-FT) and speckle-tracking echocardiography (Echo-ST) in LVNC morphology subjects with preserved LVEF and different genotypes and healthy controls.

Methods

Our retrospective study included 54 LVNC subjects with preserved LVEF and 54 control individuals. We evaluated functional and rotational parameters with CMR in the total study population and with echocardiography in 39 LVNC and 40 C individuals. All LVNC subjects were genotyped with a 174-gene next-generation sequencing panel and grouped into the subgroups: benign (B), variant of uncertain significance (VUS), and pathogenic (P).

Results

In comparison with controls, LVNC subjects had reduced apical rotational degree (p = 0.004) and one-third had negative apical rotation. While the degree of apical rotation was comparable between the three genetic subgroups, they differed significantly in the direction of apical rotation (p<0.001). In contrast to control and B groups, all four studied cardiac rotational patterns were identified in the P and VUS subgroups, namely normal rotation, positive and negative rigid body rotation, and reverse rotation. When the CMR-FT and Echo-ST methods were compared, the direction and pattern of cardiac rotation had moderate to good association (p<0.001) whereas the rotational degrees showed no reasonable correlation or agreement.

Conclusion

While measuring cardiac rotation using both CMR-FT and Echo-ST methods, subclinical mechanical differences were identified in subjects with LVNC phenotype and preserved LVEF, especially in cases with genetic involvement.
Extended-release metformin in patients with prediabetes, chro­nic heart failure and abdominal obesity in light of the effect on fat depot compartments and glucose metabolism parameters
Authors: Tsygankova O. V. , Apartseva N. E. , Latyntseva L. D. , Ryabikov A. N.
Published: September 2024

BACKGROUND: Considering the role of visceral adipose tissue deposition in the pathogenesis of heart failure with preserved ejection fraction (HFpEF) and the positive effect of metformin on weight loss, the effect of this drug on adipose tissue compartments in patients with HFpEF is interest.

AIM: To study the effect of extended-release metformin (XR) on various fat depots and parameters of insulin-glucose homeostasis in patients with HFpEF, prediabetes and abdominal obesity (AO).

MATERIALS AND METHODS: Study design: single-center, open-ended, randomized, prospective, controlled. The registration numbers of the study in the NARNIS register RNI.25.004. The study included 64 people (50% men, median age 58 [55.25; 59.75] years) with HFpEF, prediabetes and AO. All patients (groups A and B) received optimal HFpEF therapy. In group A (n=32), metformin XR 1000–1500 mg/day was additionally prescribed. All patients underwent general clinical examination, calculation of insulin resistance indices, ultrasound lipometry to determine the thickness of epicardial, preperitoneal and subcutaneous fat initially and after 6 months.

RESULTS: In group A patients, there was a decrease in waist circumference by 0.9% (p=0.002), hip circumference by 1.25% (p=0.001), body weight by 4.7% (p<0.0001), body mass index by 1.8% (p=0.001) compared with baseline. In the control group, the anthropometric parameters of the dynamics did not change. Also, in the metformin XR group, glucose levels decreased by 4.6% (p=0.009), glycated hemoglobin by 3.3% (p=0.047), insulin by 12.5% (p=0.024) and insulin resistance indices: HOMA-IR by 19.8% (p=0.009), FIRI by 19.8% (p=0.009). In contrast, patients from group B had an increase in fasting plasma insulin levels by 33.6% (p=0.035), with an increase in HOMA-IR indices by 27.4% (p=0.026) and FIRI by 26.9% (p=0.025). The dynamics of ultrasound lipometry parameters was observed only in group A: the thickness of the preperitoneal fat decreased by 14.5% (p<0.0001), the thickness of the subcutaneous fat decreased by 12.3% (p<0.0001).

CONCLUSION: In patients with prediabetes, HFpEF and AO, taking metformin XR 1000-1500 mg/day for 6 months against the background of optimal basic HFpEF therapy was associated with a decrease in subcutaneous and preperitoneal fat, also had a beneficial effect on glucose metabolism parameters compared with the control group.
Fiber Surface Treatments for Lightweight PA6 Composites
Authors: Yeetsorn Rungsima , Wanchan Waritnan , Abbas Mesum , Maiket Yaowaret , Yogesh Gaurav Kumar , Karoonsit Budsaba , Haberstroh Edmund
Published: September 2024

Natural fiber-reinforced composites (NFRC) have gained significant attention due to their eco-friendliness, affordability, and excellent mechanical properties. However, inadequate interfacial bonding between the fiber and the polymer matrix often results in inferior mechanical and thermal properties. Various surface treatments, including alkali, silane, and plasma treatments, have been developed to address this issue by modifying the fiber surface. These treatments have been shown to improve the interfacial bonding, leading to enhanced mechanical strength and thermal stability of natural fiber-reinforced PA6 composites (NFRC-PA6). In this study, we applied these surface treatments and evaluated their impact through mechanical and thermal testing. The results indicate significant improvements in the composites' properties, although challenges such as optimizing treatment parameters and ensuring uniformity persist. Future research should focus on overcoming these challenges and exploring innovative treatments to further advance the application of NFRC-PA6 composites.
Symmetry and asymmetry in certain atoms
Authors: Ravelonirina Hanitriniaina Nina RAZAFIHARISOA , Jean Jolly RAKOTO  , -	Hanitriniaina Sammy Grégoire RAVELONIRINA
Published: September 2024

Symmetry and asymmetry play a crucial role in the stability of the fundamental components of matter. Thus, the main objective of this work is to study the existence of symmetry, this universal geometric property of matter, in certain atoms, in order to provide a classification of the elements of the periodic table based on a symmetry criterion.
Sociedades mercantiles (2a edición)
Authors: Cascante Chaves María Constanza , Duque de Herrera María Victoria
Published: September 2024

En esta publicación se integran de manera sintética y armónica los principios constitucionales, las disposiciones legales y los precedentes judiciales vigentes en el derecho colombiano, y con rigor científico se tratan los desarrollos históricos y las diversas regulaciones jurídicas esenciales y determinantes en la conformación, la administración y las finalidades específicas de estas sociedades. La segunda edición de Sociedades mercantiles incluye los principios constitucionales del Derecho de Asociación, la sociedad comercial estudiada como contrato y como manifestación unilateral de voluntad, las clases de sociedades, los acuerdos de accionistas. Por la importancia del papel que juega la Superintendencia de Sociedades frente a las sociedades mercantiles, se incluyen dos capítulos: funciones administrativas y funciones jurisdiccionales de esta entidad. En las reuniones del máximo órgano social, se hace énfasis en las reuniones no presenciales y en la novedad que con motivo de la pandemia por covid-19 trajo el Decreto 398 de 2020, el cual facilitó la realización de esta clase de reuniones. Igualmente, se dedica un capítulo a las reformas estatutarias y, en especial, a los procesos de transformación, fusión y escisión, para terminar la parte general del derecho societario con la liquidación de la sociedad. Asi mismo se incorporan tablas que resumen las características de cada tipo societario para facilitar el estudio de nuestros estudiantes. Como novedad, se incluyen las sociedades BIC, de beneficio e interés colectivo. que permiten combinar en las sociedades mercantiles un objeto, social con ánimo de lucro y adicionar actividades en procura de interés de la colectividad y del medio ambiente, También es una novedad la posibilidad que hoy tienen las SAS de registrar sus valores en el registro nacional de valores y emisores., RNVE y negociarlos en bolsa de valores. La parte final contiene un glosario en materia societaria y modelos de minutas para contribuir a la práctica de nuestros estudiantes.
Genetic diversity and morphological characterization of different Adenium genotypes
Authors: Deepak S , Padmapriya S , Sathiyamurthy V A , Renuka R , Santhanakrishnan V P
Published: September 2024

The current study at Tamil Nadu Agricultural University in 2023–2024 aims to characterize the morphological features and genetic diversity of 20 Adenium genotypes. The research was performed with various vegetative and floral traits, revealing significant variations among genotypes. Notable differences were observed in plant height, branching habit, caudex circumference, leaf characteristics and floral features. Genetic analysis showed high genotypic and phenotypic coefficients of variation for traits like petal thickness, number of branches per plant and diameter of the corolla tube. These traits also exhibited high heritability and genetic advance, indicating potential for improvement through selective breeding. Other traits, such as plant height and leaf dimensions, showed moderate heritability and lower genetic advance, suggesting the influence of non-additive gene action and environmental factors. Principal component analysis identified seven principal components accounting for 85.178 % of the total variation. The first 2 components explained 40.59 % of the variability, with plant height, number of branches, flower diameter and length of anther appendages contributing significantly to PC1, while leaf width, length of corolla tube and flower weight were major contributors to PC2. This study provides valuable insight into the genetic architecture of Adenium traits, offering a foundation for future breeding efforts aimed at developing improved varieties for commercial and ornamental purposes. These findings highlight the potential for genetic improvement in Adenium through selective breeding, particularly for traits with high heritability and genetic advance.