bluuebunny/crossref_metadata_2025 huggingface dataset:
Polarization diversity schemes for gas sensing applications: a comprehensive analysis and optimal design of high-performance S
i
1−x

G
e

x
mid-infrared asymmetric rib cross-slot waveguides
Authors: Kumar Harshvardhan , Bohra Tanisha , Sharma Apoorv , Menon P. Susthitha , Hatta Agus Muhamad
Published: October 2023

This work presents the novel concept of silicon germanium (Si1−xGex) asymmetric rib cross-slot waveguides (ACWGs) as a potential solution for sensing a wide range of atmospheric gases in the mid-infrared (MIR) region. The investigation focuses on the analysis of Si1−xGex ACWGs, which encompass both vertical and horizontal slots. These waveguides are examined in the context of a polarization diversity scheme, aiming to provide robust confinement in the slot region for fundamental quasi-TE and quasi-TM modes. The fabrication of this WG can be achieved through the utilization of advanced complementary metal-oxide-semiconductor technology. In order to enhance the sensing performance of the proposed WG-based sensors, the width of both horizontal and vertical slots is optimized to maximize the total slot power confinement factor (PCF). For the optimized ACWG structure, our simulated results reveal that the fundamental quasi-TM mode exhibits a higher PCF compared to the fundamental quasi-TE mode. In particular, the PCF values for the fundamental quasi-TM mode are found to be 76.4%, 86.8%, and 88.3% at λ=3.67µm (methane: CH4), 4.47 µm (nitrous oxide: N2O), and 4.67 µm (carbon monoxide: CO), respectively. Furthermore, when the propagation loss (α) is equal to 0.5 dB/cm, the corresponding sensitivity values for CH4, N2O, and CO are 3.77×10−7ppm−1, 6.98×10−5ppm−1, and 3.53×10−5ppm−1, respectively. Additionally, with α=0.5dB/cm and SNR=1dB, the minimum detectable concentration (Cmin) of CH4, N2O, and CO is determined, yielding related values of 0.24 ppm, 1.3×10−3ppm, and 2.6×10−3ppm. The simulated results demonstrate better values of PCF, sensitivity, and Cmin when compared to previously reported sensors based on vertical slot WG, horizontal slot WG, or cross-slot WG. Thus, the proposed ACWG structure presents a potential avenue for the development of highly efficient MIR photonic gas sensors.
Ultra-small, low-cost, and simple-to-control PSP projector based on SLCD technology
Authors: Peng Renjun , Zhou Gang , Zhang Cong , Wei Chen , Wang Xiaohui , Chen Xiaoxi , Yang Lifeng , Yue Huimin , Liu Yong
Published: October 2023

Demand for ultra-small, inexpensive, and high-accurate 3D shape measurement devices is growing rapidly, especially in the industrial and consumer electronics sectors. Phase shifting profilometry (PSP) is a powerful candidate due to its advantages of high accuracy, great resolution, and insensitivity to ambient light. As a key component in PSP, the projector used to generate the phase-shifting sinusoidal fringes must be ultra-small (several millimeters), low-cost, and simple to control. However, existing projection methods make it difficult to meet these requirements simultaneously. In this paper, we present a modern technique that can be used to fabricate the desired projector. A specifically designed device based on segmented liquid crystal display (SLCD) technology is used to display the projected patterns, and a cylindrical lens is used as the projection lens. The SLCD device can display four sets of specific filled binary patterns, each yielding a sinusoidal fringe, and all four sinusoidal fringes satisfy the four-step phase shift relation. 3D shape measurement experiments verify the performance of the projector. Considering that the size of SLCD devices can be reduced to a few millimeters, the proposed technique can be easily used to manufacture ultra-small, low-cost, and simple-to-control PSP projectors.
Auto-setting multi-soliton temporal spacing in a fiber laser by a hybrid GA-PSO algorithm
Authors: Zhu Qi-Bin , Zhang Ze-Xian , Tong Lai-Yuan , Li Ti-Jian , Geng Min-Ming , Xu Wen-Cheng , Zhang Zhen-Rong , Luo Zhi-Chao
Published: October 2023

Multi-soliton operation in fiber lasers is a promising platform for the investigation of soliton interaction dynamics and high repetition-rate pulse. However, owing to the complex interaction process, precisely manipulating the temporal spacing of multiple solitons in a fiber laser is still challenging. Herein, we propose an automatic way to control the temporal spacing of multi-soliton operation in an ultrafast fiber laser by a hybrid genetic algorithm-particle swarm optimization (GA-PSO) algorithm. Relying on the intelligent adjustment of the electronic polarization controller (EPC), the on-demand temporal spacing of the double solitons can be effectively achieved. In particular, the harmonic mode locking with equal temporal spacing of double solitons is also obtained. Our approach provides a promising way to explore nonlinear soliton dynamics in optical systems and optimize the performance of ultrafast fiber lasers.
Generation of femtosecond optical vortices with multiple separate phase singularities from a Kerr-lens mode-locked Yb:KGW oscillator
Authors: Liu Xin , Yan Lisong , Chen Hongshan , Liu Heyan , Liu Hongyu , Wang Qing , Zhang Jinwei
Published: October 2023

Femtosecond optical vortices with a phase singular point have diverse applications such as microscopic particles manipulation, special-structure micro-processing and quantum information. Raising the number of singularity points can provide additional dimensions of control. Here we report for what we believe is the first time the generation of femtosecond optical vortices with multiple (two and five) singularities directly from a laser oscillator. The average powers and pulse durations of the resulting vortex pulses are several hundred milliwatts and less than 300 fs, respectively. This work represents an innovate way for obtaining femtosecond multi-vortices, opening the way to the further studies of optical vortex crystals and their applications.
Solar-pumped dual-rod Ce:Nd:YAG laser with 58 W continuous-wave output power and 5.1° tracking error compensation width
Authors: Almeida Joana , Liang Dawei , Catela Miguel , Costa Hugo , Garcia Dário , Tibúrcio Bruno D. , Guillot Emmanuel , Vistas Cláudia R.
Published: October 2023

The pursuit of high-power solar laser systems with high efficiency and capacity for large tracking error compensation is determinant for the applicability of this renewable technology. A side-pumped dual-rod Ce:Nd:YAG solar laser was developed and tested at the focus of a 2 m diameter parabolic concentrator. Maximum continuous-wave total solar laser power of 58 W was measured. To the best of our knowledge, this is the highest laser power from a Ce:NdYAG solar laser. Moreover, wide tracking error compensation width of 5.1° in the azimuthal direction was reached, being 4.25 times higher than the previous measurement without solar tracking assistance.
Manipulating plasmonic vortex based on meta-atoms with four rectangular slits
Authors: Gu Kai , Zhang Yang , Zhao Hanwen , Sun Ming , Xu Bin , Ni Bin , Liu Xuefeng , Xiong Jichuan
Published: October 2023

In this paper, four rectangular slits with the same size and regular rotation angle are regarded as the meta-atom, arranged on circular contours, to create plasmonic vortex lenses (PVLs) solely based on the geometric phase. These PVLs can achieve the same purpose of exciting surface plasmon polariton (SPP) vortices with arbitrary combinations of topological charge (TC) when illuminated by circularly polarized (CP) light with different handedness as the traditional PVLs. Furthermore, they can generate SPP vortices with different TCs and specific constant or varying electric-field intensities when excited by linearly polarized (LP) light, which marks the first instance of this phenomenon solely through geometric phase manipulation. The TC can be dynamically altered by controlling the polarization order of the incident vector beam. These PVLs not only possess advantages in terms of device miniaturization and the creation of a more uniform vortex field, as compared to PVLs based on the transmission phase, but also offer a more straightforward design process in comparison to traditional structures that rely solely on the geometric phase.
Shaping the angular spectrum of a Bessel beam to enhance light transfer through dynamic strongly scattering media
Authors: Scheidt Dennis , Arzola Alejandro V. , Quinto-Su Pedro A.
Published: October 2023

We prepare a quasi-non-diffracting Bessel beam defined within an annular angular spectrum with a spatial light modulator. The beam propagates through a strongly scattering media, and the transmitted speckle pattern is measured at one point with a Hadamard Walsh basis that divides the ring into N segments (N = 16, 64, 256, 1024). The phase of the transmitted beam is reconstructed with 3-step interferometry, and the intensity of the transmitted beam is optimized by projecting the conjugate phase at the SLM. We find that the optimum intensity is attained for the condition that the transverse wave vector k⊥ (of the Bessel beam) matches the spatial azimuthal frequencies of the segmented ring k
ϕ
. Furthermore, compared with beams defined on a 2d grid (i.e., Gaussian) a reasonable enhancement is achieved for all the k⊥ sampled with only 64 elements. Finally, the measurements can be done while the scatterer is moving as long as the total displacement during the measurement is smaller than the speckle correlation distance.
Switchable rotation of metal nanostructures in an intensity chirality-invariant focus field
Authors: Chen Yixuan , Zhou Jiakang , Xie Xi , Ma Haixiang , Zhang Shuoshuo , Xie Zhenwei , Min Changjun , Zhang Yuquan , Yuan Xiaocong
Published: October 2023

Light-induced rotation is a fundamental motion form that is of great significance for flexible and multifunctional manipulation modes. However, current optical rotation by a single optical field is mostly unidirectional, where switchable rotation manipulation is still challenging. To address this issue, we demonstrate a switchable rotation of non-spherical nanostructures within a single optical focus field. Interestingly, the intensity of the focus field is chiral invariant. The rotation switch is a result of the energy flux reversal in front and behind the focal plane. We quantitatively analyze the optical force exerted on a metal nanorod at different planes, as well as the surrounding energy flux. Our experimental results indicate that the direct switchover of rotational motion is achievable by adjusting the relative position of the nanostructure to the focal plane. This result enriches the basic motion mode of micro-manipulation and is expected to create potential opportunities in many application fields, such as biological cytology and optical micromachining.
Integrated nonlinearity calibration optical-electrical engine for FMCW LiDAR application
Authors: Wang Jing , Zhu Lin , Niu Ben
Published: October 2023

We demonstrate an integrated optical-electrical calibration module for improving the nonlinearity of the optical source for frequency-modulated continuous-wave (FMCW) LiDAR applications. The linearity of the light source has a considerable influence on FMCW LiDAR range performance, and calibration is typically necessary. However, a majority of existing calibration techniques are based on separate devices, resulting in high cost and limited integration. Our module is made up of a silicon photonic chip with a long optical delay line, a tunable phase shifter, two balanced photodetectors, and some passive components. For this module, we also built the aided amplification and voltage bias circuits. After packaging this module, we used it with our nonlinearity calibration algorithm to analyze the laser’s relative nonlinearity. After nonlinearity calibration, the laser relative nonlinearity 1-r2 could be improved to 10−6∼10−7. In the future, the calibration result of nonlinearity could be enhanced further by increasing the length of the on-chip optical delay line.
High-Q adiabatic micro-resonators on a wafer-scale ion-sliced 4H-silicon carbide-on-insulator platform
Authors: Zhou Liping , Yi Ailun , Su Yongquan , Yang Bingcheng , Zhu Yifan , Cai Jiachen , Wang Chengli , Wu Zhenyu , Song Sannian , Zhang Jiaxiang , Ou Xin
Published: October 2023

A 4H-silicon carbide-on-insulator (4H-SiCOI) has emerged as a prominent material contender for integrated photonics owing to its outstanding material properties such as CMOS compatibility, high refractive index, and high second- and third-order nonlinearities. Although various micro-resonators have been realized on the 4H-SiCOI platform, enabling numerous applications including frequency conversion and electro-optical modulators, they may suffer from a challenge associated with spatial mode interactions, primarily due to the widespread use of multimode waveguides. We study the suppression of spatial mode interaction with Euler bends, and demonstrate micro-resonators with improved Q values above 1 × 105 on ion-sliced 4H-SiCOI platform with a SiC thickness nonuniformity less than 1%. The spatial-mode-interaction-free micro-resonators reported on the CMOS-compatible wafer-scale 4H-SiCOI platform would constitute an important ingredient for the envisaged large-scale integrated nonlinear photonic circuits.
Frequency noise measurements using coherent self-heterodyne detection
Authors: Thorndahl Thomsen Simon , Far Brusatori Mónica , Hedegaard Arent Niklas , Ranjan Kumar Rakesh , Volet Nicolas
Published: October 2023

We demonstrate a refined way to extract the frequency noise (FN) spectrum of lasers by tailoring the delay in a conventional delayed self-heterodyne setup to sub-coherence lengths. The method achieves direct proportionality between electrical spectrum analyzer traces and the FN spectrum, which provide the intrinsic linewidth of the lasers. This proposed method is validated by comparing the FN spectrum with that obtained from a commercial frequency noise analyzer. The method provides a cost-effective alternative for FN measurements, which also requires minimal post-processing as compared to the state-of-the-art.
In-focus quantitative phase imaging from defocused off-axis holograms: synergistic reconstruction framework
Authors: Castaneda Raul , Trujillo Carlos , Doblas Ana
Published: October 2023

Digital holographic microscopy (DHM) enables the three-dimensional (3D) reconstruction of quantitative phase distributions from a defocused hologram. Traditional computational algorithms follow a sequential approach in which one first reconstructs the complex amplitude distribution and later applies focusing algorithms to provide an in-focus phase map. In this work, we have developed a synergistic computational framework to compensate for the linear tilt introduced in off-axis DHM systems and autofocus the defocused holograms by minimizing a cost function, providing in-focus reconstructed phase images without phase distortions. The proposed computational tool has been validated in defocused holograms of human red blood cells and three-dimensional images of dynamic sperm cells.
Rapid and collective determination of the complete “hot-spring frog” mitochondrial genome containing long repeat regions using Nanopore sequencing
Authors: Asaeda Yuka , Shiraga Kento , Suzuki Makoto , Sambongi Yoshihiro , Ogino Hajime , Igawa Takeshi
Published: October 2023

The mitochondrial genome (mt-genome) is one of the promising molecular markers for phylogenetics and population genetics. Recently, various mt-genomes have been determined rapidly by using massively parallel sequencers. However, the control region (CR, also called D-loop) in mt-genomes remain difficult to precisely determine due to the presence of repeat regions. Here, using Nanopore sequencing, we succeeded in rapid and collective determination of complete mt-genome of the hot-spring frog, Buergeria japonica, and found that its mt-genome size was 22,274 bp including CR (6,929 bp) with two types of tandem repeat motifs forming repeat regions. Comparison of assembly strategies revealed that the long- and short-read data combined together enabled efficient determination of the CR, but the short-read data alone did not. The B. japonica CR was longer than that of a congenic species inhabiting cooler climate areas, Buergeria buergeri, because of the long repeat regions in the former. During the thermal adaptation of B. japonica, the longer repeat regions in its CR may have accumulated within a period after divergence from B. buergeri.
Toward sustainable community-based tourism development: Perspectives from local people in Nhon Ly coastal community, Binh Dinh province, Vietnam
Authors: Quang Tuyen Dai , Nguyen Quynh Xuan Thi , Nguyen Hoang Van , Dang Vang Quang , Tang Nhan Thong
Published: October 2023

Community-based tourism (CBT) is no longer a new form in many countries, including Vietnam. However, the approach of CBT in a sustainable manner, especially in coastal villages, where tourism has recently emerged as an alternative livelihood, has received little attention. This study explores the impact of tourism on the lives of the local community, the level of people’s participation in tourism, and the challenges of tourism development in the coastal commune of Nhon Ly, Binh Dinh province. By utilizing a qualitative method such as observation and semi-structured interviews with 19 villagers engaged in tourism, the results show that tourism contributes significantly to the lives of the residents in Nhon Ly (e.g., improving income, changing livelihoods from fishing to tourism, improving environmental awareness). However, tourism development has obstacles related to local people’s skills and knowledge working in tourism and their limited participation in tourism policy and planning. Other issues were related to the negative impacts of tourism on cultural-social and environmental aspects in Nhon Ly. Therefore, there is a need for comprehensive coordination among all tourism stakeholders, building long-term strategies to overcome barriers toward sustainable CBT development in the future.
Determining the statistical significance of the difference between arbitrary curves: A spreadsheet method
Authors: Hristova Kalina , Wimley William C.
Published: October 2023

We present a simple, spreadsheet-based method to determine the statistical significance of the difference between any two arbitrary curves. This modified Chi-squared method addresses two scenarios: A single measurement at each point with known standard deviation, or multiple measurements at each point averaged to produce a mean and standard error. The method includes an essential correction for the deviation from normality in measurements with small sample size, which are typical in biomedical sciences. Statistical significance is determined without regard to the functionality of the curves, or the signs of the differences. Numerical simulations are used to validate the procedure. Example experimental data are used to demonstrate its application. An Excel spreadsheet is provided for performing the calculations for either scenario.
DNase I targeted degradation of neutrophil extracellular traps to reduce the damage on IgAV rat
Authors: Chen Xiu-Qi , Tu Li , Tang Qing , Zou Jia-Sen , Yun Xiang , Qin Yuan-Han
Published: October 2023

Background

In the past two years, studies have found a significant increase in neutrophil extracellular traps (NETs) in patients with IgA vasculitis (IgAV), which is correlated with the severity of the disease. NETs have been reported as an intervention target in inflammatory and autoimmune diseases. This study aimed to investigate the effect of targeted degradation of NETs using DNase I in IgAV rat model.

Methods

Twenty-four Sprague-Dawley rats were randomly divided into three groups: the IgAV model group, the DNase I intervention group and the normal control group, with an average of 8 rats in each group. The model group was established by using Indian ink, ovalbumin, and Freund’s complete adjuvant. In the intervention group, DNase I was injected through tail vein 3 days before the end of established model. The circulating cell free-DNA (cf-DNA) and myeloperoxidase-DNA (MPO-DNA) were analyzed. The presence of NETs in the kidney, gastric antrum and descending duodenum were detected using multiple fluorescences immunohistochemistry and Western blots. Morphological changes of the tissues were observed.

Results

After the intervention of DNase I, there was a significant reduction in cf-DNA and MPO-DNA levels in the intervention group compared to the IgAV model group (all P<0.001). The presence of NETs in renal, gastric, and duodenal tissues of the intervention group exhibited a significant decrease compared to the IgAV model group (P < 0.01). Moreover, the intervention group demonstrated significantly lower levels of renal MPO and citrullinated histone H3 (citH3) protein expression when compared to the IgAV model group (all P < 0.05). The HE staining results of intervention group demonstrated a significant reduction in congestion within glomerular and interstitial capillaries. Moreover, there was a notable improvement in gastric and intestinal mucosa necrosis, congestion and bleeding. Additionally, there was a substantial decrease in inflammatory cells infiltration.

Conclusion

The degradation of NETs can be targeted by DNase I to mitigate tissue damage in IgAV rat models. Targeted regulation of NETs holds potential as a therapeutic approach for IgAV.
A multi-stage group decision making approach for sustainable supplier selection based on probabilistic linguistic time-ordered incentive operator
Authors: Zhang Faming , Li Meixing , Ye Zhaoqing , Niu Yufei
Published: October 2023

This study proposes a novel multi-stage multi-attribute group decision making method under a probabilistic linguistic environment considering the development state and trend of alternatives. First, the probabilistic linguistic term set (PLTS) is used by decision makers (DMs) to describe qualitative evaluation information. Subsequently, the weights of DMs for different attributes in different periods are determined by the credibility degree, which is combined with the hesitancy degree and the similarity degree. The evaluations of different DMs for alternatives and the evaluations of DMs’ intentions to reward or punish are then aggregated. Later, the trend change level and the trend change stability of alternatives are measured through the means of reward and punishment incentives. Additionally, the probabilistic linguistic time-ordered incentive operator is proposed to aggregate the development state evaluation information and development trend evaluation information in different periods, and alternatives are prioritized by the extended TOPSIS method in the probabilistic linguistic environment. Finally, the practical use of the proposed decision framework is validated by using a sustainable supplier selection problem, and the effectiveness and the applicability of the framework are discussed through comparative analysis. The results show that the proposed approach can select suitable sustainable suppliers by considering their development state and trend in multiple stages.
A novel adaptive-weight ensemble surrogate model base on distance and mixture error
Authors: Lu Jun , Fang Yudong , Han Weijian
Published: October 2023

Surrogate models are commonly used as a substitute for the computation-intensive simulations in design optimization. However, building a high-accuracy surrogate model with limited samples remains a challenging task. In this paper, a novel adaptive-weight ensemble surrogate modeling method is proposed to address this challenge. Instead of using a single error metric, the proposed method takes into account the position of the prediction sample, the mixture error metric and the learning characteristics of the component surrogate models. The effectiveness of proposed ensemble models are tested on five highly nonlinear benchmark functions and a finite element model for the analysis of the frequency response of an automotive exhaust pipe. Comparative results demonstrate the effectiveness and promising potential of proposed method in achieving higher accuracy.
The effectiveness of mindfulness training in improving medical students’ stress, depression, and anxiety
Authors: Alzahrani Ahmed M. , Hakami Ahmed , AlHadi Ahmad , Al-maflehi Nassr , Aljawadi Mohammed H. , Alotaibi Rawan M. , Alzahrani Muhannad M. , Alammari Salem Ali , Batais Mohammed A. , Almigbal Turky H.
Published: October 2023

Introduction

There is growing interest in Mindfulness-based Stress Reduction (MBSR) program to combat mental distress in medical students. In Saudi Arabia, literature is insufficient about MBSR and its effectiveness. This study aims to measure the effectiveness of MBSR in improving mindful state, stress, anxiety, and depression in medical students. Also, the study explores the association between the attendance rate of MBSR sessions and its effectiveness. Lastly, the study examines gender differences in response to MBSR.

Methods

This is a stratified randomized controlled study of 84 medical students from two medical schools in Riyadh, Saudi Arabia. They were recruited voluntarily from November 2018 to April 2021, and allocated to MBSR and waitlist groups using a stratified randomization method based on gender. MBSR group received eight weeks of sessions through audiovisual materials. An online survey utilizing validated questionnaires assessing stress, mindfulness, anxiety, and depression was used to evaluate both groups pre-program (time 0), post-program (time 1), and three months later (time 2).

Results

Seventy-one participants completed the post-test (time 1). There were no differences between study groups at time 0 and 1. However, in 41 subjects who completed the follow-up test (time 2), the anxiety dropped significantly in MBSR group (mean difference (MD), -3.935; 95% CI, -7.580 to -0.290). Furthermore, attending more MBSR sessions was inversely correlated with depression (r, -0.556; P, 0.002), and anxiety (r, -0.630; P, 0.000). Compared to their baseline, males in MBSR group improved in stress (MD, 3.08; 95% CI, 0.30 to 5.86), anxiety (MD, 4.91; 95% CI, 3.32 to 6.50), and mindfulness (MD, -0.58; 95% CI, -1.01 to -0.15), while females improved in stress (MD, 2.64; 95% CI, 0.02 to 5.26).

Conclusion

Despite the study being interrupted by the stressful COVID-19 outbreak, the findings suggest that MBSR improved psychological outcomes when participants commit to the program.
Readiness of public schools before reopening during COVID-19 pandemic: School-based cross-sectional survey in southern Ethiopia
Authors: Endriyas Misganu , Woldemariam Belete , Shibru Endashaw , Hussen Mamush , Bedru Bersabeh , Moges Mathewos , Melka Mintesinot , Lemango Fiseha , Mate Male , Lejiso Tesfaye , Gebremedhin Biruk , Tolcha Alemu , Shiferaw Biniam , Wondimu Girma , Terefe Tesfatsion , Ayele Sinafikish , Misganaw Tebeje , Samuel Teka , Kelaye Temesgen , Gebru Agegnehu , Assefa Amare , Getachew Wogene , Yalew Bereket , Geleta Dereje
Published: October 2023

Background

School closures in response to the COVID-19 impacted children’s education, protection, and wellbeing. After understanding these impacts and that children were not super spreaders, countries including Ethiopia decided to reopen schools with specified preconditions. But when deciding to reopen schools, the benefits and risks across education, public health and socio-economic factors have to be evaluated. However, there was information gap on status of schools as per preconditions. Hence, this study was designed to investigate status of schools in Southern Ethiopia.

Methods

School based cross-sectional study was conducted in October 2020 in Southern Ethiopia. Sample of 430 schools were included. National school reopening guideline was used to develop checklist for assessment. Data was collected by public health experts at regional emergency operation center. Descriptive analysis was performed to summarize data.

Results

A total of 430 schools were included. More than two thirds, 298 (69.3%), of schools were from rural areas while 132 (30.7%) were from urban settings. The general infection prevention and water, sanitation and hygiene (IPC-WASH) status of schools were poor and COVID-19 specific preparations were inadequate to meet national preconditions to reopen schools during the pandemic. Total score from 24 items observed ranged from 3 to 22 points with mean score of 11.75 (SD±4.02). No school scored 100% and only 41 (9.5%) scored above 75% while 216 (50.2%%) scored below half point that is 12 items.

Conclusion

Both the basic and COVID-19 specific IPC-WASH status of schools were inadequate to implement national school reopening preconditions and general standards. Some of strategies planned to accommodate teaching process and preconditions maximized inequalities in education. Although COVID-19 impact lessened due to vaccination and other factors, it is rational to consider fulfilling water and basic sanitation facilities to schools to prevent communicable diseases of public health importance.
Catalytic Combustion of Volatile Organic Compounds (VOCs) over Perovskite Oxides: A Review
Authors: Mistri Rajib , Dule Madhab , Kumar Bidyapati
Published: October 2023

Volatile organic compounds (VOCs) are one of the crucial outdoor as well as indoor air pollutants. Recently, the elimination of volatile organic compounds is become more attractive due to its potentiality of long-term human health effects. Among the different existing methods for the removal of VOCs, the catalytic combustion is the best convenient method due to its operational simplicity, cost effectiveness, high efficiency and industrial acceptability. Various perovskite oxides have been widely studied as suitable catalysts for the removal of VOCs because of their tunable physico-chemical properties, compositional/structural exibility and high thermochemical stability. The morphology, material composition and surface as well as bulk properties of perovskite oxides is the key determining factors for catalytic efficiency. The suitable metal or non-metal doping, controlling morphology (nano-structuring, three-dimensional ordered microporous (3DOM) building) and hybrid construction (perovskite as support for other active catalysts and other oxides as support for active perovskite catalyst) may have a remarkable effect on the surface as well as bulk properties and consequently the catalytic efficiency for ther removal reactions of VOCs are also effected. In this review article, different aspects of the current development in perovskite oxides catalysts for VOCs combustion with a special highlighting on the material designing, like doping, morphology controlling, surface modication and hybrid construction are presented.
Motherhood Practice and Identity Negotiation of Married Migrant Women Suffering Family Disorganization
Authors:   Crisis and Emergency Management: Theory and Praxis, Kim So Hee
Published: October 2023

The purpose of this study is to identify the patterns of motherhood practice and identity negotiation of married migrant women experiencing family disorganization in the context of social structure. To this purpose, the study conducted in depth interview with 18 married migrant women who have either been divorced or bereaved of their spouses and analyzed their oral data. The results of this study revealed that there were four types of identity negotiations for married migrant women. This is as follows: ‘becoming Korean with a combination of stable citizenship and motherhood’, ‘becoming mother with a combination of incomplete citizenship and motherhood’, ‘living as oneself with stable citizenship and leading a self-centered life,’ and ‘living in a blind spot in which they are neither a citizen nor a mother’. The key point to these multiple styles is to the repositioning as ‘a mother of citizen’. This means ‘becoming Korean as a mother of a citizen,’ which is a strategic choice available to migrant women as an aspect of their motherhood practice and a way to secure their identity in Korean society.
An Analysis on the Characteristics of Accidents in Tourism and Leisure Facilities
Authors:   Crisis and Emergency Management: Theory and Praxis, Cho Hyeon U , Won Jin Young , Chung Jea Hak
Published: October 2023

The purpose of this study is to analyze the current status and change trends of tourism·leisure facilities in South Korea, and to identify factors (types and causes) of accidents in each facility by collecting accident cases (from 2011 to 2023) and conducting chi-square test. As a result, the tourism and leisure facilities have rapidly increased throughout the country within the last 10 years. Some facilities have become deteriorated, operated in unmanned systems, longer and higher, and more unique and combined. In tramway facilities (cableway, monorail), stationary facility mainly occurred due to mechanical defects compared with other facilities. In landscape facilities (pedestrian suspension bridge, sky-walk), fall accidents mostly caused by individual negligence and operating system problem. Finally, in adventure facilities (zip-line), collision (including rear-end) accidents significantly resulted from mechanical and operating system factors. Therefore, it should be required more intensive safety management for accident prevention of tourism and leisure by improving legal and institution, and developing safety education and training programs.
Evolución de la educación superior chilena desde la perspectiva del ecualizador de gobernanza
Authors: Brunner José Joaquín , Alarcón Mario
Published: October 2023

Este artículo examina la evolución de la gobernanza del sistema de educación superior de Chile durante los últimos 50 años. Se considera la narrativa de la Nueva Gerencia Pública (NGP) como marco conceptual y se aplica el ecualizador de gobernanza como modelo analítico para estudiar los cambios en distintos períodos caracterizados por diferentes contextos políticos. Los resultados evidencian que después de 50 años, la gobernanza del sistema de educación superior chileno ha transitado desde un régimen de autogobierno académico hacia un esquema híbrido con predominio de una coordinación mediante regulación del Estado, competencia y gobierno gerencial. Se revisan los resultados de estudios previos bajo el lente del ecualizador de gobernanza aplicado a los sistemas de educación superior de Italia, Hungría, Ucrania y Polonia. Se constata una tendencia común hacia la configuración de modelos de gobernanza híbridos y se advierten limitaciones en los regímenes ideales de gobernanza para representar la complejidad actual de los sistemas nacionales de educación superior.
Acoustic scattering properties of a seagrass, Cymodocea nodosa: in-situ measurements
Authors: Mutlu Erhan , Olguner Cansu
Published: October 2023

Marine prairies play various crucial roles in marine ecosystems. The seagrasses that compose them are one of the most important components engineering the marine coastal system, providing significant spatial niches. Some of the seagrasses found in marine prairies are protected, and it is not recommended to sample them with destructive methods. Non-destructive methods such as remote sensing have been proposed as important means of studying these protected species. In the present study, the acoustic scattering properties of Cymodocea nodosa were studied with two different in/ex situ experiments conducted on a Turkish Mediterranean coast using a scientific echosounder (206 kHz split beam transducer) in different months over the years 2011 and 2012. After a series of acoustic processes, correlations and regression equations were established between different acoustic parameters of the Elementary Distance Sampling Units and biometric traits of below/above ground parts of the seagrass. The relationships were logarithmically established producing first a Rayleigh zone, followed by a geometrical zone that occurred with increased biometrics. No seasonal difference occurred in the relationships for the above-ground parts. Unlike the leaves, seagrass sheaths demonstrated unstable echo energy, inconsistent relationships, and unexplained acoustic responses over the span of several months. Regarding leaf density changing in time, significant relationships were explained as a function of the acoustic zones. Four points were highlighted to explain the differences in the estimations between the two experiments; i) the backscattering strengths depended on strength of biomass and its fractions (leaf area, shoot density and volume) between the two experiments, ii) the first experiment measured backscattering strength from individual specimens, but the second experiment was performed on the total biomass of seagrass per unit area, iii) different frequency response to the biometrics occurred in the two experiments, and iv) the non-linear effect of the sheath could not be separated from that of the leaf during the second experiment. The present study was the first attempt to characterize relationships between the biometric and acoustic backscattering properties of C. nodosa, and will guide researchers in future use of non-destructive methods.
On Waring’s problem for larger powers
Authors: Brüdern Jörg , Wooley Trevor D.
Published: October 2023

Let

G
⁢

(
k
)

{G(k)}

denote the least number s having the property that every
sufficiently large natural number is the sum of at most s positive integral k-th powers.
Then for all

k
∈
ℕ

{k\in\mathbb{N}}

, one has

G
⁢

(
k
)

⩽

⌈

k
⁢

(

log
⁡
k

+
4.20032

)

⌉

.

G(k)\leqslant\lceil k(\log k+4.20032)\rceil.

Our new methods improve on all bounds available hitherto when

k
⩾
14

{k\geqslant 14}

.
Platelet-derived growth factor-stimulated pulmonary artery smooth muscle cells regulate pulmonary artery endothelial cell dysfunction through extracellular vesicle miR-409-5p
Authors: Heo Jeongyeon , Kang Hara
Published: October 2023

Platelet-derived growth factor (PDGF)-induced changes in vascular smooth muscle cells (VSMCs) stimulate vascular remodeling, resulting in vascular diseases such as pulmonary arterial hypertension. VSMCs communicate with endothelial cells through extracellular vesicles (EVs) carrying cargos, including microRNAs. To understand the molecular mechanisms through which PDGF-stimulated pulmonary artery smooth muscle cells (PASMCs) interact with pulmonary artery endothelial cells (PAECs) under pathological conditions, we investigated the crosstalk between PASMCs and PAECs via extracellular vesicle miR-409-5p under PDGF stimulation. miR-409-5p expression was upregulated in PASMCs upon PDGF signaling, and it was released into EVs. The elevated expression of miR-409-5p was transported to PAECs and led to their impaired function, including reduced NO release, which consequentially resulted in enhanced PASMC proliferation. We propose that the positive regulatory loop of PASMC-extracellular vesicle miR-409-5p-PAEC is a potential mechanism underlying the proliferation of PASMCs under PDGF stimulation. Therefore, miR-409-5p may be a novel therapeutic target for the treatment of vascular diseases, including pulmonary arterial hypertension.
User-centered design in mobile human-robot cooperation: consideration of usability and situation awareness in GUI design for mobile robots at assembly workplaces
Authors: Colceriu Christian , Theis Sabine , Brell-Cokcan Sigrid , Nitsch Verena
Published: October 2023

Mobile cobots can increase the potential for assembly work in industry. For human-friendly automation of cooperative assembly work, user-centered interfaces are necessary. The design process regarding user interfaces for mobile human-robot cooperation (HRC) shows large research gaps. In this article an exemplary approach is shown to design a graphical user interface (GUI) for mobile HRC at assembly workplaces. The design is based on a wireframe developed to support situation awareness. An interactive mockup is designed and evaluated. This is done in two iterations. In the first iteration, a user analysis is carried out using a quantitative survey with n = 31 participants to identify preferred input modalities and a qualitative survey with n = 11 participants that addresses touch interfaces. The interactive mockup is developed by implementing design recommendations of the usability standards ISO 9241 – 110, 112 and 13. A heuristic evaluation is conducted with n = 5 usability experts and the measurement of situation awareness with n = 30 end users. In the second iteration, findings from the preceding iteration are implemented in the GUI and a usability test with n = 20 end users is conducted. The process demonstrates a combination of methods that leads to high usability and situation awareness in mobile HRC.
Effect of Information Literacy on Academic Performance of Business Students in Pakistan
Authors: Mughari Shahzeb , Naveed Muhammad Asif , Rafique Ghulam Murtaza
Published: October 2023

The present research investigated the effect of information literacy on the academic performance of business students enrolled at the top seven business education institutions from urban Sindh, Pakistan. A quantitative research approach using a cross-sectional survey was used to conduct this investigation. The data were collected from 385 business students enrolled in different degree programs using a questionnaire. The recruitment of the participants was done through proportionate stratified simple random and systematic sampling techniques, with the results indicating that business students are information literate. In addition, the information literacy of business students appeared as a positive predictor of their academic performance. These results may inform policy and practice to improve business education and might be useful for business educators, policymakers, librarians, and business accrediting bodies (e.g., National Business Education Accreditation Council and Higher Education Commission) in designing a needs-based information literacy instruction program and curriculum for business students of all levels for better human-information interaction. This study contributed to the existing literature on the effectiveness of information literacy in academia, particularly on business students’ academic performance, as no such research was available in the existing literature at the time of writing this article, specifically from the South-Asian region.
Multiplexing in photonics as a resource for optical ternary content-addressable memory functionality
Authors: London Yanir , Van Vaerenbergh Thomas , Ramini Luca , Descos Antoine , Buonanno Luca , Youn Jinsung , Li Can , Graves Catherine E. , Fiorentino Marco , Beausoleil Raymond G.
Published: October 2023

In this paper, we combine a Content-Addressable Memory (CAM) encoding scheme previously proposed for analog electronic CAMs (E-CAMs) with optical multiplexing techniques to create two new photonic CAM architectures—wavelength-division multiplexing (WDM) optical ternary CAM (O-TCAM) and time-division multiplexing (TDM) O-TCAM. As an example, we show how these two O-TCAM schemes can be implemented by performing minor modifications in microring-based silicon photonic (SiPh) circuits originally optimized for exascale interconnects. Here, our SiPh O-TCAM designs include not only the actual search engine, but also the transmitter circuits. For the first time, we experimentally demonstrate O-TCAM functionality in SiPh up to∼4Gbps${\sim} 4\,\,\text{Gbps}$and we prove in simulation feasibility for speeds up to 10 Gbps, 10 times faster than typical E-TCAMs at the expense of higher energy consumption per symbol of our O-TCAM Search Engine circuits than the corresponding E-TCAMs. Finally, we identify which hardware and architecture modifications are required to improve the O-CAM’s energy efficiency towards the level of E-CAMs.
Dynamic Shrinkage Priors for Large Time-Varying Parameter Regressions Using Scalable Markov Chain Monte Carlo Methods
Authors: Hauzenberger Niko , Huber Florian , Koop Gary
Published: October 2023

Time-varying parameter (TVP) regression models can involve a huge number of coefficients. Careful prior elicitation is required to yield sensible posterior and predictive inferences. In addition, the computational demands of Markov Chain Monte Carlo (MCMC) methods mean their use is limited to the case where the number of predictors is not too large. In light of these two concerns, this paper proposes a new dynamic shrinkage prior which reflects the empirical regularity that TVPs are typically sparse (i.e. time variation may occur only episodically and only for some of the coefficients). A scalable MCMC algorithm is developed which is capable of handling very high dimensional TVP regressions or TVP Vector Autoregressions. In an exercise using artificial data we demonstrate the accuracy and computational efficiency of our methods. In an application involving the term structure of interest rates in the eurozone, we find our dynamic shrinkage prior to effectively pick out small amounts of parameter change and our methods to forecast well.
Network of International Cooperative Learning Educators and Enthusiasts (NICLEE): Cultivating Global Connections
Authors: Arató Ferenc , Davidson Neil , Stevahn Laurie , Sharan Yael
Published: October 2023

Desmond Tutu speaks to the fundamental truth that the human species relies on cooperation for its survival. While we may see ourselves as individuals, the reality is that we are all interconnected and our fates are intertwined. This is especially true when it comes to learning and education. We cannot learn in isolation; we need teachers, mentors, peers, and a community that supports us. The act of learning itself is a cooperative process, where we share knowledge and ideas with others to construct deeper understanding. In short, the quote reminds us that we are not alone in this world, and that our success and happiness are tied to the success and happiness of others. It is only through cooperation and collaboration that we can achieve great things and create a better future for all.
Recommendations on Use of DIC in Experimental Geotechnics
Authors: Chouhan Kritesh , Rai Harsh , Chavda Jitesh T.
Published: October 2023

Image-based deformation measurement techniques, like digital image correlation (DIC), are used to measure the displacement of soil particles and thereby to investigate the behavior of geo-structure in experimental geotechnics. The precision of the measurement from the DIC technique depends on the position of the camera and light panels, the color temperature of light, size of the region of interest (RoI), type and relative density of sand, seeding ratio, type of camera, and strain rate used in experiments. In the paper, the effect of above-mentioned parameters is investigated experimentally in 1-g model tests. The studies show that the precision in DIC measurements is dependent on the position of camera and light panels, size of RoI, texture of the sand, and seeding ratio. However, the relative density of sand and strain rate do not significantly affect the results from the DIC analysis. The efficacy in the measurement of the large deformations and suitability of smartphone cameras using DIC are also addressed. Last, we developed recommendations to obtain precise results from DIC in experimental geotechnics.