bluuebunny/crossref_metadata_2025 huggingface dataset:
Polarization-Dependent Fiber Metasurface with Beam Collimating and Deflecting
Authors: Ma Yuemin , Sang Di , Lin Yi , An Qiang , Sun Zhanshan , Fu Yunqi
Published: May 2024

Metasurfaces can arbitrarily manipulate the amplitude, phase, and polarization of optical fields on subwavelength scales. Due to their arbitrary manipulation and compact size, the metasurface can be well integrated with optical fibers. Herein, we demonstrate a polarization-dependent metasurface using birefringent meta-atoms, which can independently control X- and Y-polarization incident light. Each meta-atom allows for the division of phase into 16 steps ranging from 0 to 2π for both X- and Y-polarization, resulting in 256 nanopillars selected from the meta-atom library to satisfy the required phase. With the different effective refractive indices of the cuboid meta-atoms along the X- and Y-axis, we can achieve collimation of the X-polarization emitted beam from an optical fiber while deflecting orthogonally polarized light. As a result, the proposed metasurface collimates an X-polarized beam with a beam radius of 20 μm at z = 1 mm and 43.9 μm at z = 2 mm. Additionally, the metasurface can effectively deflect the Y-polarized beam to 36.01°, consistent with the results of the theoretical computation. The proposed metasurface exhibits a deflection efficiency of 55.6% for Y-polarized beams with a relative polarization efficiency of 82.2%, while the efficiency for the X-polarization is 71.4%. Our work is considered a promising application for optical communication, sensing, and quantum measurement.
A Fast Time Synchronization Method for Large Scale LEO Satellite Networks Based on A Bionic Algorithm
Authors: Xu Yue , Dong Tao , Yin Jie , Zhang Ziyong , Liu Zhihui , Jiang Hao , Wu Jing
Published: May 2024

A fast time synchronization method for large-scale LEO satellite networks based on a bionic algorithm is proposed. Because the inter-satellite links are continuously established and interrupted due to the relative motion of the satellites, the topology of the LEO satellite networks is time varying. Firstly, according to the ephemeris information in navigation messages, a connection table which records the connections between satellites is generated. Then, based on the connection table, the current satellite network topology is calculated and generated. Furthermore, a bionic algorithm is used to select some satellites as time source nodes and calculate the hierarchy of the clock transmission tree. By taking the minimum level of the time transmission tree as the optimization objective, the time source nodes and the clock stratums of the whole satellite networks are obtained. Finally, the onboard computational center broadcasts the time layer table to all the satellites in the LEO satellite networks and the time synchronization links can be established or recovered fast.
Chirped Integrated Bragg Grating Design
Authors: Praena José Ángel , Carballar Alejandro
Published: May 2024

We analyze the two classic methods for chirped Integrated Bragg Gratings (IBGs) in Silicon-on-Insulator technology using the transfer matrix method based on the effective refractive index (neff) technique, which translates the geometry of an IBG into a matrix of neff depending on the wavelength. We also implement a procedure that allows engineering of the chirped IBG parameters, given a required bandwidth (BW) and group delay (GD). Finally, a complementary method for designing chirped IBG is proposed, showing a significant improvement in the bandwidth of the device or a moderation in the variation of the geometrical parameters of the grating.
Broadband High-Linear FMCW Light Source Based on Spectral Stitching
Authors: Sun Liang , Zhou Xinguang , Zhao Haohao , Xu Shichang , Wu Zihan , Yuan Guohui , Wang Zhuoran
Published: May 2024

The key to realizing a high-performance frequency-modulated continuous wave (FMCW) laser frequency-sweeping light source is how to extend the frequency-swept bandwidth and eliminate the effect of nonlinearity. To solve these issues, this paper designs a broadband high-linear FMCW frequency-sweeping light source system based on the combination of fixed temperature control and digital optoelectronic phase-locked loop (PLL), which controls the temperatures of the two lasers separately and attempts to achieve the coarse spectral stitching based on a time-division multiplexing scheme. Furthermore, we uses the PLL to correct the frequency error more specifically after the coarse stitching, which achieves the spectrum fine stitching and, meanwhile, realizes the nonlinearity correction. The experimental results show that our scheme can successfully achieve bandwidth expansion and nonlinearity correction, and the sweeping bandwidth is twice as much as that of the original single laser. The full-width half-maximum (FWHM) of the FMCW output is reduced from 150 kHz to 6.1 kHz, which exhibits excellent nonlinear correction performance. The relative error of the FMCW ranging system based on this frequency-swept light source is also reduced from 1.628% to 0.673%. Therefore, our frequency-swept light source with excellent performance has a promising application in the FMCW laser ranging system.
Carbon Dot-Decorated Polystyrene Microspheres for Whispering-Gallery Mode Biosensing
Authors: Starovoytov Anton A. , Soloveva Evgeniia O. , Kurassova Kamilla , Bogdanov Kirill V. , Arefina Irina A. , Shevchenko Natalia N. , Vartanyan Tigran A. , Dadadzhanov Daler R. , Toropov Nikita A.
Published: May 2024

Whispering gallery mode (WGM) resonators doped with fluorescent materials find impressive applications in biological sensing. They do not require special conditions for the excitation of WGM inside that provide the basis for in vivo sensing. Currently, the problem of materials for in vivo WGM sensors are substantial since their fluorescence should have stable optical properties as well as they should be biocompatible. To address this we present WGM microresonators of 5–7 μm, where the dopant is made of carbon quantum dots (CDs). CDs are biocompatible since they are produced from carbon and demonstrate bright optical emission, which shows different bands depending on the excitation wavelength. The WGM sensors developed here were tested as label-free biosensors by detecting bovine serum albumin molecules. The results showed WGM frequency shifting, with the limit of detection down to 10−16 M level.
Next-Generation Dual Transceiver FSO Communication System for High-Speed Trains in Neom Smart City
Authors: Elsawy Yehia , Alatawi Ayshah S. , Abaza Mohamed , Moawad Azza , Aggoune El-Hadi M.
Published: May 2024

Smart cities like Neom require efficient and reliable transportation systems to support their vision of sustainable and interconnected urban environments. High-speed trains (HSTs) play a crucial role in connecting different areas of the city and facilitating seamless mobility. However, to ensure uninterrupted communication along the rail lines, advanced communication systems are essential to expand the coverage range of each base station (BS) while reducing the handover frequency. This paper presents the dual transceiver free space optical (FSO) communication system as a solution to achieve these objectives in the operational environment of HSTs in Neom city. Our channel model incorporates log-normal (LN) and gamma–gamma (GG) distributions to represent channel impairments and atmospheric turbulence in the city. Furthermore, we integrated the siding loop model, providing valuable insights into the system in real-world scenarios. To assess the system’s performance, we formulated the received signal-to-noise ratio (SNR) of the network under assumed fading conditions. Additionally, we analyzed the system’s bit error rate (BER) analytically and through Monte Carlo simulation. A comparative analysis with reconfigurable intelligent surfaces (RIS) and relay-assisted FSO communications shows the superior coverage area and efficiency of the dual transceiver model. A significant reduction of up to 76% and 99% in the number of required BSs compared to RIS and relay, respectively, is observed. This reduction leads to fewer handovers and lower capital expenditure (CAPEX) costs.
A Numerical Model to Predict the Relaxation Phenomena in Thermoset Polymers and Their Effects on Residual Stress during Curing—Part I: A Theoretical Formulation and Numerical Evaluation of Relaxation Phenomena
Authors: Verde Raffaele , D’Amore Alberto , Grassia Luigi
Published: May 2024

This paper analyzes the effect of crosslinking reactions on a thermoset polymer’s viscoelastic properties. In particular, a numerical model to predict the evolution of epoxy’s mechanical properties during the curing process is proposed and implemented in an Ansys APDL environment. A linear viscoelastic behavior is assumed, and the scaling of viscoelastic properties in terms of the temperature and degree of conversion is modeled using a modified version of the TNM (Tool–Narayanaswamy–Mohynian) model. The effects of the degree of conversion and structural relaxation on epoxy’s relaxation times are simultaneously examined for the first time. This formulation is based on the thermo-rheological and chemo-rheological simplicities hypothesis and can predict the evolution of epoxy’s relaxation phenomena. The thermal–kinetic reactions of curing are implemented in a homemade routine written in APDL language, and the structural module of Ansys is used to predict the polymer’s creep and stress relaxation curves at different temperatures and degrees of conversion.
Experimental Evaluation of a Granular Damping Element
Authors: Avdić Sanel , Nagode Marko , Klemenc Jernej , Oman Simon
Published: May 2024

Due to their advantages—longer internal force delay compared to bulk materials, resistance to harsh conditions, damping of a wide frequency spectrum, insensitivity to ambient temperature, high reliability and low cost—granular materials are seen as an opportunity for the development of high-performance, lightweight vibration-damping elements (particle dampers). The performance of particle dampers is affected by numerous parameters, such as the base material, the size of the granules, the flowability, the initial prestress, etc. In this work, a series of experiments were performed on specimens with different combinations of influencing parameters. Energy-based design parameters were used to describe the overall vibration-damping performance. The results provided information for a deeper understanding of the dissipation mechanisms and their mutual correlation, as well as the influence of different parameters (base material, granule size and flowability) on the overall damping performance. A comparison of the performance of particle dampers with carbon steel and polyoxymethylene granules and conventional rubber dampers is given. The results show that the damping performance of particle dampers can be up to 4 times higher compared to conventional bulk material-based rubber dampers, even though rubber as a material has better vibration-damping properties than the two granular materials in particle dampers. However, when additional design features such as mass and stiffness are introduced, the results show that the overall performance of particle dampers with polyoxymethylene granules can be up to 3 times higher compared to particle dampers with carbon steel granules and conventional bulk material-based rubber dampers.
The Inversion Method of Shale Gas Effective Fracture Network Volume Based on Flow Back Data—A Case Study of Southern Sichuan Basin Shale
Authors: Tang Dengji , Wu Jianfa , Zhao Jinzhou , Zeng Bo , Song Yi , Shen Cheng , Ren Lan , Huang Yongzhi , Wang Zhenhua
Published: May 2024

Fracture network fracturing is pivotal for achieving the economical and efficient development of shale gas, with the connectivity among fracture networks playing a crucial role in reservoir stimulation effectiveness. However, flow back data that reflect fracture network connectivity information are often ignored, resulting in an inaccurate prediction of the effective fracture network volume (EFNV). The accurate calculation of the EFNV has become a key and difficult issue in the field of shale fracturing. For this reason, the accurate shale gas effective fracture network volume inversion method needs to be improved. Based on the flow back characteristics of fracturing fluids, a tree-shaped fractal fracture flow back mathematical model for inversion of EFNV was established and combined with fractal theory. A genetic algorithm workflow suitable for EFNV inversion of shale gas was constructed based on the flow back data after fracturing, and the fracture wells in southern Sichuan were used as an example to carry out the EFNV inversion. The reliability of the inversion model was verified by testing production, cumulative gas production, and microseismic results. The field application showed that the inversion method proposed in this paper can obtain tree-shaped fractal fracture network structure parameters, fracture system original pressure, matrix gas breakthrough pressure, fracture compressibility coefficient, reverse imbibition index, equivalent main fracture half length, and effective initial fracture volume (EIFV). The calculated results of the model belong to the same order of magnitude as those of the HD model and Alkouh model, and the model has stronger applicability. This research has important theoretical guiding significance and field application value for improving the accuracy of the EFNV calculation.
Management of Pregnancy in a Patient with Familial Hypercholesterolemia and Previous Myocardial Infarction—Treatment with LDL Apheresis: A Case Report
Authors: Milincic Milos , Todorovic Jovana , Dugalic Stefan , Novakovic Ivana , Macura Maja , Lalic Katarina , Gojnic Dugalic Miroslava
Published: May 2024

Familial hypercholesterolemia, a genetic disorder marked by elevated low-density lipoprotein cholesterol (LDL-C), poses significant risks for premature atherosclerosis and cardiovascular diseases, particularly during pregnancy. One of the safe methods of treating this condition in pregnancy is with the use of LDL apheresis. We present a 38-year-old primigravida with homozygous Familial Hypercholesterolemia (HoFH), ischemic cardiomyopathy, and angina pectoris. Two years before conception, extremely elevated lipid levels prompted statin therapy and lifestyle changes. Stent placements followed acute myocardial infarction. When planning pregnancy, statins were discontinued, but lipid levels elevated. LDL apheresis was initiated, achieving a 60% reduction. Throughout pregnancy, 16 LDL apheresis sessions were performed every 14 days, maintaining optimal lipid profiles. A cesarean section was performed in the 38th week of gestation, delivering a healthy infant. The patient resumed statin therapy after 8 months of breastfeeding. The patient maintained cardiovascular health, demonstrating the feasibility of controlled HoFH pregnancies. This case highlights the successful management of HoFH during pregnancy using LDL apheresis, ensuring maternal and fetal well-being. Future research on novel treatments and their safety during pregnancy is essential for refining therapeutic approaches in similar cases.
Long-Time Coherent Integration for the Spatial-Based Bistatic Radar Based on Dual-Scale Decomposition and Conditioned CPF
Authors: Li Suqi , Wang Yihan , Liang Yanfeng , Wang Bailu
Published: May 2024

This paper addresses the problem of weak maneuvering target detection in the space-based bistatic radar system through long-time coherent integration (LTCI). The space-based bistatic radar is vulnerable to the high-order range migration (RM) and Doppler frequency migration (DFM), since the target, the receiver and the transmitter all can play fast movement independently. To correct high- order RM and DFM, this usually involves joint high-dimensional parameter searching, incurring a large computational burden. In our previous work, a dual-scale (DS) decomposition of motion parameters was proposed, in which the optimal GRFT is conditionally decoupled into two cascade procedures called the modified generalized inverse Fourier transform (GIFT) and generalized Fourier transform (GFT), resulting in the DS-GRFT detector. However, even if the DS-GRFT detector preserves the superior performance and dramatically decreases the complexity, high-dimensional searching is still required. In this paper, by analyzing the structure of the DS-GRFT detector, we further designed a conditioned cubic phase function (CCPF) tailored to the range–slow-time signal after GIFT, breaking the joint high-dimensional searching into independent one-dimensional searching. Then, by connecting the proposed CCPF with the GIFT, we achieved a new LTCI detector called the DS-GIFT-CCPF detector, which obtained a significant computational cost reduction with acceptable performance loss, as demonstrated in numerical experiments.
Specification of Self-Adaptive Privacy-Related Requirements within Cloud Computing Environments (CCE)
Authors: Kitsiou Angeliki , Sideri Maria , Pantelelis Michail , Simou Stavros , Mavroeidi Aikaterini-Georgia , Vgena Katerina , Tzortzaki Eleni , Kalloniatis Christos
Published: May 2024

This paper presents a novel approach to address the challenges of self-adaptive privacy in cloud computing environments (CCE). Under the Cloud-InSPiRe project, the aim is to provide an interdisciplinary framework and a beta-version tool for self-adaptive privacy design, effectively focusing on the integration of technical measures with social needs. To address that, a pilot taxonomy that aligns technical, infrastructural, and social requirements is proposed after two supplementary surveys that have been conducted, focusing on users’ privacy needs and developers’ perspectives on self-adaptive privacy. Through the integration of users’ social identity-based practices and developers’ insights, the taxonomy aims to provide clear guidance for developers, ensuring compliance with regulatory standards and fostering a user-centric approach to self-adaptive privacy design tailored to diverse user groups, ultimately enhancing satisfaction and confidence in cloud services.
Ultra-Wideband Vertical Transition in Coplanar Stripline for Ultra-High-Speed Digital Interfaces
Authors: Kim Mun-Ju , Lee Jung-Seok , Min Byung-Cheol , Choi Jeong-Sik , Kumar Sachin , Choi Hyun-Chul , Kim Kang-Wook
Published: May 2024

A design method for an ultra-wideband coplanar-stripline-based vertical transition that can be used for ultra-high-speed digital interfaces is proposed. A conventional via structure, based on a differential line (DL), inherently possesses performance limitations (<10 GHz) due to difficulties in maintaining constant line impedance and smooth electric field transformation, in addition to the effects of signal skews, FR4 fiber weave, and unbalanced EM interferences. DL-based digital interfaces may not meet the demands of ultra-high-speed digital data transmission required for the upcoming 6G communications. The use of a coplanar stripline (CPS), a type of planar balanced line (BL), for the vertical transition, along with the ultra-wideband DL-to-CPS transition, mostly removes the inherent and unfavorable issues of the DL and enables ultra-high-speed digital data transmission. The design process of the transition is simplified using the analytical design formulas, derived using the conformal mapping method, of the transition. The characteristic line impedances of the transition are calculated and found to be in close agreement with the results obtained from EM simulations. Utilizing these results, the CPS-based vertical transition, maintaining the characteristic line impedance of 100 Ω, is designed and fabricated. The measured results confirm its ultra-wideband characteristics, with a maximum of 1.6 dB insertion loss and more than 10 dB return loss in the frequency range of DC to 30 GHz. Therefore, the proposed CPS-based vertical transition offers a significantly wider frequency bandwidth, i.e., more than three times that of conventional DL-based via structures.
Radiation Damage Mechanisms and Research Status of Radiation-Resistant Optical Fibers: A Review
Authors: Li Jicong , Chen Qi , Zhou Jia , Cao Zhi , Li Tianchi , Liu Fang , Yang Zhongyuan , Chang Shangwen , Zhou Keyuan , Ming Yuzhou , Yan Taihong , Zheng Weifang
Published: May 2024

In recent years, optical fibers have found extensive use in special environments, including high-energy radiation scenarios like nuclear explosion diagnostics and reactor monitoring. However, radiation exposure, such as X-rays, gamma rays, and neutrons, can compromise fiber safety and reliability. Consequently, researchers worldwide are focusing on radiation-resistant fiber optic technology. This paper examines optical fiber radiation damage mechanisms, encompassing ionization damage, displacement damage, and defect centers. It also surveys the current research on radiation-resistant fiber optic design, including doping and manufacturing process improvements. Ultimately, it summarizes the effectiveness of various approaches and forecasts the future of radiation-resistant optical fibers.
Effects of 17β-Estradiol Pollution on Microbial Communities and Methane Emissions in Aerobic Water Bodies
Authors: Gao Zihao , Zheng Yu , Li Zhendong , Ruan Aidong
Published: May 2024

17β-Estradiol (E2) is a widely present trace pollutant in aquatic environments. However, its impact on microbial communities in aerobic lake waters, which are crucial for methane (CH4) production, remains unclear. This study conducted an E2 contamination experiment by constructing laboratory-simulated aerobic microecosystems. Using 16S rRNA high-throughput sequencing, the effects of E2 on bacterial and archaeal communities were systematically examined. Combined with gas chromatography, the patterns and mechanisms of E2’s impact on CH4 emissions in aerobic aquatic systems were uncovered for the first time. Generally, E2 contamination increased the randomness of bacterial and archaeal community assemblies and weakened microbial interactions. Furthermore, changes occurred in the composition and ecological functions of bacterial and archaeal communities under E2 pollution. Specifically, two days after exposure to E2, the relative abundance of Proteobacteria in the low-concentration (L) and high-concentration (H) groups decreased by 6.99% and 4.01%, respectively, compared to the control group (C). Conversely, the relative abundance of Planctomycetota was 1.81% and 1.60% higher in the L and H groups, respectively. E2 contamination led to an increase in the relative abundance of the methanogenesis functional group and a decrease in that of the methanotrophy functional group. These changes led to an increase in CH4 emissions. This study comprehensively investigated the ecotoxicological effects of E2 pollution on microbial communities in aerobic water bodies and filled the knowledge gap regarding aerobic methane production under E2 contamination.
Evaluating Treatment Outcomes and Tuberculosis Infection Risks: A Comparative Study of Centralized Hospitalization vs. Home-Based Treatment
Authors: Xianyu Fangming , Huang Yuemei , Guo Shengqiong , Chongsuvivatwong Virasakdi
Published: May 2024

Background: Guizhou Province in Southwest China has experimented with a centralized hospitalization (CH) treatment for active and severe cases of pulmonary tuberculosis (PTB). The objective of this study was to compare treatment outcomes of patients with tuberculosis (TB) receiving care in a CH setting with those receiving home-based (HB) care. In addition, this study aimed to assess the probability of their household contacts contracting tuberculosis infection. Method: A retrospective review of medical records was undertaken for patients with TB who completed their treatment in four counties in Guizhou, China, spanning from January 2022 to August 2023. In addition, a cross-sectional survey was conducted on the tuberculin skin test (TST) among household contacts of new patients with TB who had completed their treatment. Results: In the retrospective study, 94.8% had successful CH treatment, and 93.1% had successful HB treatment (p value = 0.70). In the prospective study, 559 and 448 household contacts of patients receiving CH treatment had 16 positive and 89 negative TST results, whereas those with HB treatment showed 26 positive and 74 negative TST results. Regarding a logistic regression analysis, the CH group was nearly two times more likely to test negative on the TST, 1.95 (95% CI: 0.98, 3.92). After adjusting for confounding variables, the odds ratio increased significantly to 4.42 (95% CI: 1.22, 16.04). Conclusions: CH for treatment of TB did not show superior success rates, but it may reduce the risk of transmitting tuberculosis infection to household contacts compared to home treatment.
Uncovering the First AGN Jets with AXIS
Authors: Connor Thomas , Bañados Eduardo , Cappelluti Nico , Foord Adi
Published: May 2024

Jets powered by AGN in the early Universe (z≳6) have the potential to not only define the evolutionary trajectories of the first-forming massive galaxies but to enable the accelerated growth of their associated SMBHs. Under typical assumptions, jets could even rectify observed quasars with light seed formation scenarios; however, not only are constraints on the parameters of the first jets lacking, observations of these objects are scarce. Owing to the significant energy density of the CMB at these epochs capable of quenching radio emission, observations will require powerful, high angular resolution X-ray imaging to map and characterize these jets. As such, AXIS will be necessary to understand early SMBH growth and feedback. This White Paper is part of a series commissioned for the AXIS Probe Concept Mission; additional AXIS White Papers can be found at the AXIS website.
The Parallel Compact Object CALculator: An Efficient General Relativistic Initial Data Solver for Compact Objects
Authors: Boukas Lambros , Tsokaros Antonios , Uryū Kōji
Published: May 2024

Every numerical general relativistic investigation starts from the solution of the initial value equations at a given time. Astrophysically relevant initial values for different systems lead to distinct sets of equations that obey specific assumptions tied to the particular problem. Therefore, a robust and efficient solver for a variety of strongly gravitating sources is needed. In this work, we present the OpenMP version of the Compact Object CALculator (COCAL) on shared memory processors. We performed extensive profiling of the core COCAL modules in order to identify bottlenecks in efficiency, which we addressed. Using modest resources, the new parallel code achieves speedups of approximately one order of magnitude relative to the original serial COCAL code, which is crucial for parameter studies of computationally expensive systems such as magnetized neutron stars, as well as its further development towards more realistic scenarios. As a novel example of our new code, we compute a binary quark system where each companion has a dimensionless spin of 0.43 aligned with the orbital angular momentum.
Artificial Floating Islands for the Removal of Nutrients and Improvement of the Quality of Urban Wastewater
Authors: Hernández-Vásquez Luis Alfredo , Romo-Gómez Claudia , Alvarado-Lassman Alejandro , Prieto-García Francisco , Camacho-López Cesar , Acevedo-Sandoval Otilio Arturo
Published: May 2024

A high amount of nutrients can be found in urban wastewater (UW), which makes it difficult to treat. The purpose of this research was to evaluate the potential of the aquatic macrophytes Eichhornia crassipes, Pistia stratiotes, and Salvinia molesta in the treatment of UW. To evaluate the potential of each macrophyte, phytoremediation bioassays were established; the hydraulic retention time for each bioassay was 15 days. The physicochemical analysis of the water samples considered pH, turbidity, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), chemical oxygen demand (COD), total carbon (TC), phosphates (PO43-P), nitrate (NO3-N), and total nitrogen (TN). To evaluate the phytoremediation potential of each plant, the bioconcentration factors (BCFs) and translocation factors (TFs) for NO3-N and PO43-P were evaluated. Likewise, the relative growth rates (RGRs) and total chlorophyll production of the macrophytes were measured. The results showed that the highest efficiency was achieved with the bioassays with E. crassipes, with removal values of 69.7%, 68.8%, 58.7%, 69.4%, 56.3%, and 40.9% for turbidity, COD, TOC, PO43-P, NO3-N, and TN, respectively. The phytoremediation potential results showed that, for BCF, the highest value was 4.88 mg/g of PO43-P with E. crassipes, and for TF, it was 6.17 mg/g of PO43-P with S. molesta. The measurement of RGR and total chlorophyll for E. crassipes showed an increase of 0.00024 gg−1d−1 and an increase of 4.5%, respectively. On the other hand, the other macrophytes suffered decreases in chlorophyll content and RGR. Thus, E. crassipes is defined as the macrophyte with the greatest potential for the UW phytoremediation process.
Flood Propagation Characteristics in a Plain Lake: The Role of Multiple River Interactions
Authors: Wu Qiuqin , Wang Zhichao , Xu Xinfa , Huang Zhiwen , Wen Tianfu , You Wensun , Xia Yang
Published: May 2024

Plain lakes play a crucial role in the hydrological cycle of a watershed, but their interactions with adjacent rivers and downstream water bodies can create complex river–lake relationships, often leading to frequent flooding disasters. Taking Poyang Lake as an example, this paper delves into its interaction with the Yangtze River, revealing the spatiotemporal patterns of flood propagation within the lake and its impact on surrounding flood control measures. The aim is to provide insights for flood management in similar environments worldwide. This study employs a comprehensive approach combining hydrological statistical analysis and two-dimensional hydrodynamic modeling, based on extensive hydrological, topographic, and socio-economic data. The results indicate that the annual maximum outflow from Poyang Lake is primarily controlled by floods within the watershed, while the highest annual lake water level is predominantly influenced by floods from the Yangtze River. The peak discharge typically reaches the lake outlet within 48 h, with the peak water level taking slightly longer at 54 h. However, water storage in the lake can shorten the time that it takes for the peak discharge to arrive. When converging with floods from the Yangtze River, the peak water level may be delayed by up to 10 days, due to the top-supporting interaction. Furthermore, floods from the “Five Rivers” propagate differently within the lake, affecting various lake regions to differing degrees. Notably, floods from the Fu River cause the most significant rise in the lake’s water level under the same flow rate. The top-supporting effect from the Yangtze River also significantly impacts the water surface slope of Poyang Lake. When the Yangtze River flood discharge significantly exceeds that of the “Five Rivers” (i.e., when the top-supporting intensity value, f, exceeds four), the lake surface becomes as flat as a reservoir. During major floods in the watershed, the water level difference in the lake can increase dramatically, potentially creating a “dynamic storage capacity” of up to 840 million cubic meters.
Sustainable Banana-Waste-Derived Biosorbent for Congo Red Removal from Aqueous Solutions: Kinetics, Equilibrium, and Breakthrough Studies
Authors: Daffalla Samah , Taha Amel , Da’na Enshirah , El-Aassar Mohamed R.
Published: May 2024

This study investigates the adsorption of Congo red (CR) dye from wastewater using banana peel biochar (BPBC) in both batch and fixed-bed column modes. BPBC was characterized using FTIR, SEM, XRD, TGA, and BET analysis, revealing a predominantly mesoporous structure with a surface area of 9.65 m2/g. Batch adsorption experiments evaluated the effectiveness of BPBC in removing CR, investigating the influence of the BPBC dosage, initial CR concentration, and solution pH. Results showed optimal CR removal at pH levels below 4, suggesting a favorable electrostatic interaction between the adsorbent and the dye. Furthermore, a pseudo-first-order kinetic model best described the adsorption process. The Freundlich isotherm provided a better fit compared to the Langmuir and Dubinin–Radushkevich (D-R) models, implying a heterogeneous adsorption surface. The calculated maximum adsorption capacity (Qm) from the Langmuir model was 35.46 mg/g. To assess continuous operation, breakthrough curves were obtained in fixed-bed column experiments with varying bed heights (1–3.6 cm). The results demonstrated efficient CR removal by BPBC, highlighting its potential for wastewater treatment. Finally, this study explored the feasibility of BPBC regeneration and reuse through four adsorption–desorption cycles.
New Insights into Turbulent and Laminar Flow Relationships Using Darcy–Weisbach and Poiseuille Laws
Authors: Fiorillo Francesco , Esposito Libera , Ginolfi Michele , Leone Guido
Published: May 2024

Analytical solutions for turbulent and laminar water flow conditions are developed considering the drainage process of a simple tank reservoir, using the Darcy–Weisbach and the Poiseuille laws, respectively. Near the critical value of the Reynolds number, the Darcy–Weisbach and the Poiseuille laws do not match, and there is a gap regarding the possibility of describing the drainage analytically. This gap corresponds to the critical zone of the Moody diagram, where theoretically a constant discharge occurs under a decreasing hydraulic gradient. In the critical zone, this hydraulic behavior of the flow reflects the different energy losses occurring during the drainage, as the laminar flow is a more efficient flow condition than the turbulent one. In natural systems (e.g., springs and karst aquifers), a smooth transition from the turbulent to the laminar water flow occurs due to the heterogeneity in the medium.
Frecuencia de E.coli y Klebsiella spp productoras de betalactamasas en cultivos procesados en un laboratorio clínico
Authors: Muñoz Guartazaca Rocío Manuela , Bigoni Ordóñez Gabriele Davide
Published: May 2024

Introducción: la resistencia antibiótica en bacterias patógenas como Escherichia coli y Klebsiella spp. productoras de betalactamasas, han surgido como un problema global de salud pública. Su presencia, se asocia con infecciones intrahospitalarias y comunitarias, aumentando la morbilidad y la mortalidad de los pacientes. Objetivo: determinar la frecuencia de E.coli y Klebsiella spp productoras de betalactamasas en cultivos procesados en un laboratorio clínico.Métodos: se realizó un estudio descriptivo de diseño documental. La muestra estuvo constituida por un total de 1465 resultados de cultivos positivos para Escherichia coli o Klebsiella spp. en el periodo 2022. Para la recolección de la información, se tuvo acceso a la base de datos anonimizada del laboratorio en una hoja de Excel para su posterior análisis. Los datos fueron tabulados en SPSS versión 25. Resultados: el análisis de bacterias productoras de BLEE mostró una positividad del 22,3% en E. coli y 46,1% en Klebsiella spp. E. coli presentó mayor frecuencia de negativos (77,7%) en comparación con Klebsiella spp. La presencia de E. coli fue más común en muestras de orina (90,6%) y en otras muestras como esputo y heridas cutáneas (21,3%). Se evaluaron 8 antibióticos, y se destacó la alta sensibilidad para amikacina (AK) (99,6% y 98,0%) y elevada resistencia ampicilina (AM) (91,5% y 100%) en ambas especies. Ciprofloxacino (CIP) y Trimetropin/Sulfametoxazol (STX) mostraron relativa frecuencia mayor de resistencia. Conclusión: los resultados muestran una alta frecuencia de bacterias productoras de BLEE en E. coli y Klebsiella spp., con una mayor prevalencia en Klebsiella spp. Además, la resistencia a AM, CIP y STX destaca la importancia de una gestión adecuada de la resistencia antimicrobiana.
Parasitosis intestinales en niños de edad escolar en Jancao (Huánuco) Perú
Authors: Palacios Zevallos Juana Irma , Esteban Robladillo Isabel , Velázquez Bernal Libia Rocío , Velázquez Bernal Alex Camilo , Vigíl Pinedo Nazly Leticia , Enriquez Medina Giancarlo Remigio
Published: May 2024

Las infecciones parasitarias intestinales son comunes a nivel mundial, especialmente en naciones en desarrollo, y conllevan una significativa carga de morbilidad. Objetivo. Estimar la prevalencia de parasitismo intestinal en los niños y niñas en edad escolar de 6 a 12 años que residen en el centro poblado Jancao (Huánuco) Perú. Materiales y métodos. Se desarrolló mediante un estudio observacional de cohorte transversal. Se calculó una muestra con un nivel de confianza del 95%, un error estimado del 5% y una proporción esperada de enfermos de 0.2. La muestra calculada fue de 186 personas. Los criterios de inclusión considerados fueron varon o hembra, de 6 a 12 años. Resultados. Fueron positivos 27% de los indviduos muestreados. La Giardía lambia y la Tenia solium tuvieron los mayores porcentajes de prevalencia en la población estudiada 24% y 18% respectivamente, ambos porcentajes difieren significativamente con los de Entoameba histolytica y Enterobius vermicularis para p<2.2e-16. La distribución por sexos de la prevalencia de las parasitosis identíficadas no mostró diferencias significativas en ninguna de las variantes analizadas. La distribución de parasitosis intestinales según tres estratos etareos de forma general no generó diferencias significativas entre los valores observados. Conclusiones. La parasitosis de mayor prevalencia en niños entre las edades comprendidas de 6 a 7 años, 8 a 9 años, 10 a 12 años en el centro poblado Jancao de Huánuco en Perú corresponden a Giardia lambia y Tenia solium.
Ansiedad en estudiantes de secundaria en tiempos de pandemia: Revisión Sistemática
Authors: León-Crispin Patricia , Méndez-Vergaray Juan , Flores Edward
Published: May 2024

El aislamiento social y el confinamiento forzado debido a la pandemia tuvo graves efectos en la salud mental de los estudiantes, que se manifestó cómo ansiedad y estrés. Objetivo. La investigación tuvo como propósito analizar los niveles de ansiedad en estudiantes de secundaria. Metodología. La búsqueda de información se realizó en las bases de datos Scopus y Ebsco, utilizando las ecuaciones: “Anxiety AND High school students”, “Trait Anxiety AND High school students”, “State anxiety AND High school students”; la información recabada se almacenó en la bandeja de Mendeley; dicha información fue analizada por títulos, resumen, palabras clave, resultados y conclusiones. El análisis de la información encriptada en Mendeley contó con 35 artículos, de los cuales 30 fueron cuantitativos y 5 cualitativos; además, el análisis por países demostró que las investigaciones sobre este tópico se realizaron con mayor énfasis en Brasil (6), en España (4) y en EE.UU. (4). El análisis de los aportes evidenció que la carencia de aparatos tecnológicos y el cambio de una educación presencial a otra virtual tuvo consecuencias inusuales de estrés y ansiedad en estudiantes y docentes. Además, se observó incremento en la agresividad, problemas en la salud mental, insomnio, pérdida del apetito entre otros. Conclusión. El confinamiento social y los cambios abruptos en la educación generaron en los agentes educativos trastornos en la salud mental y emocional.
Detecting Spam Reviews in Arabic by Deep Learning
Authors: Aljadani Eman , Assiri Fatmah , Alshutayri Areej
Published: May 2024

Online reviews are frequently used by consumers to make decisions about online purchases, hotel bookings, car rentals, and other choices because online shopping has grown in popularity over the past few years. Reviews are now crucial to both the customer and the business. As writing fake reviews comes with financial gain, opinion spam activities have increased. Some unethical companies may hire workers to write reviews to influence consumers’ purchasing decisions; therefore, detecting spam reviews is a very important task. We compiled a large dataset of Arabic reviews consisting of spam and non-spam that are categorized by crowd-sourcing approach. Then, we applied deep learning algorithms to detect spam reviews. To the best of our knowledge, there are no prior studies utilized deep learning to classify reviews that are written in Arabic. Convolutional Neural Network (CNN) and Bidirectional Long Short-Term Memory (BiLSTM) models were used, and an accuracy of 97% was achieved by both algorithms. To further improve the results, unbalanced issues were solved by oversampling and undersampling techniques. The results of them are improvements in the precision, recall, and F1-score for spam reviews. For example, in CNN F1-score for spam class increased from 79% to 90% with undersampling and became 82% with oversampling.
Engelli Bireyler İçin Kentsel Tarihi Alanlarda Erişilebilirliği Arttırmaya Yönelik Peyzaj Tasarım Yaklaşımları: Göbeklitepe Ören Yeri (Şanlıurfa) Örneği
Authors: Gür Necmettin , Kahraman Özgür
Published: May 2024

Engellilik, bir etkinliğin veya fiilin gerçekleştirilmesi için bireyin herhangi bir yönden kısıtlanmış olması durumudur. Kentsel yaşam içerisinde toplumun bütün bireylerinin kamusal veya özel tüm yapı ve alanlara eşit derecede ulaşabilir ve erişebilir olması gerekir. Aynı zamanda kentsel yaşamın önemli birer parçası olan tarihi alanlar da tıpkı kentsel diğer alanlar gibi ulaşılabilir ve erişilebilir olması gerekmektedir. Bundan dolayı kentsel tarihi alanların peyzaj tasarım ve planlamalarında engelsiz peyzaj yaklaşımları ve erişilebilirlik temel esası benimsenmelidir. Bu çalışmada engelli bireyler için kentsel tarihi alanlarda erişilebilirliğini arttırmaya yönelik peyzaj tasarım yaklaşımları sunmak amaçlanmıştır. Amaca yönelik olarak da Göbeklitepe Ören Yeri örnek alan seçilmiş ve engelsiz peyzaj yaklaşımları ve erişilebilirlik açısından incelemiştir. Literatür taraması ile engelsiz peyzaj yaklaşımları ve erişilebilirliğin sağlanması için gerekli standartlar belirlenmiştir. Daha sonrasında ören yeri alanı belirlenen standartlar çerçevesinde yürüyüş yolları ve zemin elemanları, hissedilebilir yürüme yüzeyleri, rampalar, merdivenler, aydınlatma elemanları, oturma elemanları, işaret-bilgilendirme araçları ve çöp kutuları, bitkisel materyal başlıkları altında ayrı ayrı değerlendirilmiştir. Değerlendirme ve incelemelerin ardından ören yerinin GZFT (SWOT) analizi yapılmış ve sonuç olarak alanın erişilebilirlik ve engelsiz peyzaj yaklaşımları açısından önemli derecede eksikliklerinin bulunduğu ve bu noktada önlem ve düzeltmelere ihtiyaç duyduğu belirlenmiştir. Alan üzerinde belirlenen eksiklikler ve düzeltme ihtiyaçları belirlendikten sonra alan için önlemler sıralanmış, tarihi alanlar için de engelsiz peyzaj yaklaşımları ve erişilebilirlik adına önerilerde bulunulmuştur.
Reference legal system as a mass media (on the example of RLS “Consultant Plus”)
Authors: Potyarkin D. E.
Published: May 2024

The main task of the legal reference system (LRS) is to facilitate the search and analysis of legal documents — regulatory (normative) legal acts, information messages and analytical materials. All texts, contained in the LRS, regardless of legal status, have a common legal specialization. The content of the system, its main core are normative legal acts. With the development of the system, information and analytical materials begin to play an important role in it. Such texts can be compared with publications generally accepted in journalism, especially in online media. All LRS content is intended for an indefinite circle of people — it is not formed for a specific customer. LRS has its own permanent name, daily releases of information materials. Finally, its electronic form of distribution is registered as mass media. The listed formal criteria raise the question of whether LRS can be considered as an unconventional form of mass media.
Lord, save the Russian land! Church and propaganda during the Great Patriotic War
Authors: Kovalev B. N.
Published: May 2024

The Soviet state viewed the Orthodox Church not just as an ideological competitor, but also as a force that could restore the old order. Church and religion were perceived not as an anachronism, but as a serious ideological adversary and class enemy. However, the attack of Nazi Germany on the USSR showed that in the face of the threat of an external enemy, the consolidation of all forces was required. Under these conditions, in July 1941, the newspaper Bezbozhnik [Antitheist] ceased to exist having published its last issue. Atheistic propaganda went into decline. It was replaced by national patriotism. In many works of art (feature and documentary films) and newspaper articles a positive image of an Orthodox priest or a godly man appeared. For Nazi propagandists, this was a very dangerous sign: from the very beginning of hostilities, they presented themselves exclusively as defenders of the Church and religion. In fact, Nazism was alien to the ideas of Christianity.
ORGANIZATIONAL AND ECONOMIC MECHANISM FOR THE DEVELOPMENT OF INNOVATIVE AREAS OF THE SERVICE SECTOR
Authors:   Lugansk Vladimir Dahl State University, Tkhor E. S. , Makarova E. I. ,   Lugansk Vladimir Dahl State University
Published: May 2024

The article considers theoretical approaches to the formation of organizational and eco-nomic mechanism of development of innovative areas of the service sector, which allows designing long-term strategies aimed at improving the efficiency of innovative projects of enterprises of this sphere. The concept of organizational and economic mechanism of development of innovative direc-tions of the sphere of services, its main characteristics and requirements, according to which it should ensure the effectiveness of innovative development of the sphere of services, is considered. It is offered to understand a totality of organizational and economic levers of managerial influence di-rected on formation, use and improvement of organizational, industrial, technical-technological, fi-nancial, economic, personnel, ecological and safety resources for maximization of profit of the en-terprise, and also strengthening of competitive advantages in the market and cost of business under the organizational and economic mechanism of development of innovative directions of the sphere of services. The dynamics of indicators of innovation activity of enterprises of the service sector in Russia is investigated. Generalized indicators of innovative development of enterprises of the Russian service sector are systematized, according to the results of which it is concluded that enterprises are mainly engaged in modernization and optimization of processes to reduce production costs. The or-ganizational and economic mechanism is presented, the mutual coordination of the process stages and the influence of its components allow formalizing and managing the development and imple-mentation of innovations. The construction of organizational and economic mechanism of manage-ment of innovative development of enterprises in the service sector creates the necessary prerequi-sites for improving the efficiency of innovative projects and ensuring the sustainability of competi-tiveness in the conditions of growing competition and increasing the level of globalization of the world market of services. The described organizational and economic mechanism of development of innovative directions of the service sector allows designing long-term strategies aimed at improving the efficiency of innovative projects implementation.