bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Tannic Acid Coated Polyvinylidene Fluoride Membrane for Filtration of River Water Containing High Natural Organic Matter
Authors: Dewi Rosmaya , Shamsuddin Norazanita , Abu Bakar Muhammad Saifullah , Thongratkaew Sutarat , Faungnawakij Kajornsak , Bilad Muhammad Roil
Published: November 2023

River water can be used as a source of drinking water. However, it is vital to consider the existence of natural organic matter (NOM) and its possible influence on water quality (low turbidity, high color). The level of NOM in river water significantly impacts the ecosystem’s health and the water’s quality, and needs to be removed. A membrane-based approach is attractive for treating NOM successfully, but is still hindered by the membrane fouling problem. This study aims to develop polyvinylidene fluoride (PVDF)-based membranes customized for NOM removal from river water. The anti-fouling property was imposed by a coating of tannic acid (TA) and Fe3+ on the pre-prepared PVDF membrane. The results show that the TA–Fe coatings were effective, as demonstrated by the FTIR spectra, SEM, and EDS data. The coatings made the membrane more hydrophilic, with smaller pore size and lower clean water permeability. Such properties offer enhanced NOM rejections (up to 100%) and remarkably higher fouling recovery (up to 23%), desirable for maintaining a long-term filtration performance.
Validation of a Liquid Chromatography Coupled to Mass Spectrometry Method for Glyphosate and Aminomethylphosphonic Acid in Urine for Human Biomonitoring Using Combined Hybrid Anion-Exchange and Hydrophilic Interaction Liquid Chromatography
Authors: Polledri Elisa , Mercadante Rosa , Fustinoni Silvia
Published: November 2023

Glyphosate-based herbicides are the most widely used pesticides in the world; however, the toxicity of glyphosate (GlyP) toward humans, especially its carcinogenicity, is controversial. The aim of this work was to validate a rapid assay for measuring GlyP and its metabolite aminomethylphosphonic acid (AMPA) in urine for human biomonitoring. The analytes were purified via solid-phase extraction in the presence of isotopically labeled internal standards. An LC-MS/MS assay was developed using a column with a novel hybrid stationary phase combined with anion exchange and hydrophilic interaction liquid chromatography. Detection and quantification were performed using negative electrospray ionization in a hybrid triple quadrupole/linear ion trap mass spectrometer. The retention times for AMPA and GlyP were 1.44 and 7.24 min, respectively. Calibration curves showed a linear dynamic range of up to 40 µg/L, inter- and intra-run precisions <7.5%, and accuracies within 10% of the theoretical concentrations. The limits of quantification were 0.1 µg/L and 0.5 µg/L for GlyP and AMPA, respectively. The matrix effect bias was controlled using internal standards. Successful participation in external quality assurance exercises strengthens the validity of the method. The assay was applied to the measurement of GlyP and AMPA in the urine of 9 urban residents, 26 rural residents, and 12 agricultural workers; while AMPA was mostly not quantifiable, the median GlyP values were 0.1 and 0.34 µg/L in rural residents and workers, respectively. The assay is useful to assess GlyP and AMPA in human urine following different exposure scenarios.
Unveiling the Socio-Economic Fragility of a Major Urban Touristic Destination through Open Data and Airbnb Data: The Case Study of Bologna, Italy
Authors: Nalin Alessandro , Cameli Leonardo , Pazzini Margherita , Simone Andrea , Vignali Valeria , Lantieri Claudio
Published: November 2023

In the last decades, tourism in urban areas has been constantly increasing. The need for short-term accommodations has been coupled with the emergence of internet-based services, which makes it easier to match demand (i.e., tourists) and supply (i.e., housing). As a new mass tourist destination, Bologna, Italy, has been experiencing tensions between tourists and long-, mid-, or short-term renters. The possibility of easy profits for lessees has led to an increase in such housing, which can be rented out either for touristic reasons or not. This paper aims to unveil the contribution of short-term rental accommodations in distorting the real estate market and conditioning social and economic inequalities. To do this, multiple linear regression analyses (MLR) were performed between accommodation density, real estate market information, and indicators about social, economic, and demographic vulnerability and fragility. Analyses were based on official open data and datasets from a major web-based hospitality exchange platform, i.e., Airbnb, able to provide information on registered accommodations, e.g., type, characteristics (e.g., number of bedrooms and average rating), and location. Outputs of the analyses reveal the role of Airbnb in both rental market and social, economic, and demographic vulnerability and fragility and, hence, can be a solid tool for public policies, both housing- and tourism-related.
Performance Evaluation of Fiber Near-Infrared (NIR) Optic Probes for Quality Control of Curd Hardness in Cheese Produced by Spray-Dried Milk
Authors: Meza Lesther , Aleman Ricardo S. , Marcia Jhunior , Yadav Ajitesh , Castillo Manuel
Published: November 2023

This study aims to provide the dairy industry with a direct control model focused on milk coagulation by using multifiber probes to determine parameters in the curding process, such as cutting time, at a lower cost. The main objective of the research is to confirm that a multifiber NIR light scattering probe can be used to predict the elastic modulus of curd during milk coagulation in cheese production. Two randomized complete block designs were used with a 3 × 3 factorial arrangement of three protein levels (3%, 3.5% and 4%) and three wavelengths (870 nm, 880 nm and 890 nm). Using a multifiber probe at a wavelength of 880 nm allowed obtaining a better optical response of the sensor during enzymatic milk coagulation than the 870 nm. It showed greater sensitivity to variations in the protein content of the milk and lower variation in the response. The multifiber probe at a wavelength of 880 nm generated a NIR light backscatter profile like those obtained with other systems. The results showed that the prediction model parameters had a variation as a function of the protein content, which opens the possibility of improving the prediction model’s performance substantially. Furthermore, the initial voltage obtained with the probe responded linearly to the different protein levels in milk. This fact would make it possible, at least theoretically, to estimate protein concentration with the same inline probe for G’ determination, facilitating the incorporation of a corrective protein factor in the prediction models using a single instrument.
Complications Associated with Oblique Lumbar Interbody Fusion: A Systematic Review
Authors: Tan Quan Rui , Wong Russell Andrew , Kaliya-Perumal Arun-Kumar , Oh Jacob Yoong-Leong
Published: November 2023

The main advantage of Oblique Lumbar Interbody Fusion (OLIF) is its ability to provide safe access to the lumbar spine while being a robust interbody fusion technique through a minimally invasive approach. This study reviews the postoperative complications of OLIF, offering a comprehensive understanding of its advantages and disadvantages. A total of 27 studies with 1275 patients were shortlisted based on our selection criteria. Complications were categorized into intra-operative, immediate post-operative, and delayed post-operative and were interpreted based on surgical procedure into stand-alone OLIF, OLIF with posterior stabilisation, and unspecified. Major complications exhibited a pooled prevalence of just 1.7%, whereas the overall pooled prevalence of complications was 24.7%. Among the subgroups, the stand-alone subgroup had the lowest prevalence of complications (14.6%) compared to the unspecified subgroup (29.6%) and the OLIF L2-5 with posterior stabilisation subgroup (25.8%). Similarly, for major complications, the stand-alone subgroup had the lowest prevalence (1.4%), while the OLIF L2-5 with posterior stabilisation subgroup (1.8%) and the unspecified OLIF L2-5 subgroup (1.6%) had higher rates. However, the differences were not statistically significant. In conclusion, the rate of major complications after OLIF is minimal, making it a safe procedure with significant benefits outweighing the risks. The advantages of OLIF L2-5 with posterior stabilisation over stand-alone OLIF L2-5 is a subject of discussion.
Understanding the Effects of Post-Deposition Sequential Annealing on the Physical and Chemical Properties of Cu2ZnSnSe4 Thin Films
Authors: Catana Diana-Stefania , Zaki Mohamed Yassine , Simandan Iosif-Daniel , Buruiana Angel-Theodor , Sava Florinel , Velea Alin
Published: November 2023

Cu2ZnSnSe4 thin films have been synthesized by employing two magnetron-sputtering depositions, interlaced with two sequential post-deposition heat treatments in low vacuum, Sn+Se and Se–rich atmospheres at 550 °C. By employing successive structural analysis methods, namely Grazing Incidence X–Ray Diffraction (GIXRD) and Raman Spectroscopy, secondary phases such as ZnSe coexisting with the main kesterite phase have been identified. SEM peered into the surface morphology of the samples, detecting structural defects and grain profiles, while EDS experiments showed off–stoichiometric elemental composition. The optical bandgaps in our samples were calculated by a widely used extrapolation method from recorded transmission spectra, holding values from 1.42 to 2.01 eV. Understanding the processes behind the appearance of secondary phases and occurring structural defects accompanied by finding ways to mitigate their impact on the solar cells’ properties is the prime goal of the research beforehand.
Dynamics of Particles with Electric Charge and Magnetic Dipole Moment near Schwarzschild-MOG Black Hole
Authors: Murodov Sardor , Rayimbaev Javlon , Ahmedov Bobomurat , Hakimov Abdullo
Published: November 2023

The study of electromagnetic interactions among test particles with electric charges and magnetic dipole moments is of great significance when examining the dynamics of particles within strong gravitational fields surrounding black holes. In this work, we focus on investigating the dynamics of particles possessing both electric charges and magnetic dipole moments in the spacetime of a Schwarzschild black hole within the framework of modified gravity (MOG), denoted as a Schwarzschild-MOG black hole. Our approach begins by offering a solution to Maxwell’s equations for the angular component of the electromagnetic four potentials within Schwarzschild-MOG spacetime. Subsequently, we derive the equations of motion and establish the effective potential for particles engaged in circular motion. This is achieved using a hybrid formulation of the Hamilton–Jacobi equation, encompassing interactions between electric charges and magnetic dipole moments, the external magnetic field (assumed to be asymptotically uniform), and interactions between the particles and the MOG field. Furthermore, we investigate the impacts of these three types of interactions on critical parameters, including the radius of innermost stable circular orbits (ISCOs), as well as the energy and angular momentum of particles when situated at their respective ISCOs. Finally, a detailed analysis concerning the effects of these interactions on the center-of-mass energy is presented in collisions involving neutral, electrically charged, and magnetized particles.
New Convergence Theorems for Pseudomonotone Variational Inequality on Hadamard Manifolds
Authors: Ma Zhaoli , Wang Lin
Published: November 2023

In this paper, we propose an efficient viscosity type subgradient extragradient algorithm for solving pseudomonotone variational inequality on Hadamard manifolds which is of symmetrical characteristic. Under suitable conditions, we obtain the convergence of the iteration sequence generated by the proposed algorithm to a solution of a pseudomonotone variational inequality on Hadamard manifolds. We also employ our main result to solve a constrained convex minimization problem and present a numerical experiment to illustrate the asymptotic behavior of the algorithm. Our results develop and improve some recent results.
Some Analysis of the Coefficient-Related Problems for Functions of Bounded Turning Associated with a Symmetric Image Domain
Authors: Arif Muhammad , Abbas Muhammad , Alhefthi Reem K. , Breaz Daniel , Cotîrlă Luminiţa-Ioana , Rapeanu Eleonora
Published: November 2023

In the last few years, numerous subfamilies of univalent functions, whether directly or indirectly associated with exponential functions, have been introduced and thoroughly investigated. Among these, the families Se*, Ce and Re defined by subordination to ez have been intensively investigated. While the coefficient problem on the class Se* and Ce has been solved in many cases, in this paper, we mainly intend to compute the sharp estimates of some initial coefficients, the Feketo–Szegö inequality, and the sharp bounds of second- and third-order Hankel determinants for functions belonging to the class Re. This work has the potential to significantly enrich and enhance the exploration of univalent functions in conjunction with exponential functions, making the field more comprehensive and robust.
Analysis of Novel Energy-Efficient Converters to Ensure the Required Quality of Electrical Energy
Authors: Udovichenko Aleksey , Grishanov Evgeniy , Kosykh Evgeniy , Mekhtiyev Ali
Published: November 2023

This article proposes several solutions for the use of novel AC voltage regulators as electrical energy quality conditioners and for the use of a half-bridge voltage inverter circuit as an active filter. This study was carried out with a real object, and more attention was paid to it. Structural models of electrical energy quality assurance systems, the calculation of control system elements and experimental results are presented. In particular, the use of a half-bridge voltage inverter circuit was considered as a replacement for the passive filter of the battery charger and rectifier device. AC voltage regulators are also used as compensators for higher-current harmonics, namely active filters and reactive power, voltage drop, voltage unbalance and flicker effect compensators. Block diagrams of power quality conditioners are presented, control algorithms are developed and the results of the current high-frequency harmonics compensation, reactive power and signal balancing are presented. The results of an active filter experiment based on the NRT 160.220 charge-rectifier device circuit showed a reduction in ripple of up to 1% with smaller dimensions compared to a passive filter. The control characteristics and external characteristics of the regulators are removed. The dependences of the current THD factor and the power factor are presented depending on the modulation depth for AC voltage regulator circuits used as power quality conditioners.
Responses of Mytilus galloprovincialis in a Multi-Stressor Scenario: Effects of an Invasive Seaweed Exudate and Microplastic Pollution under Ocean Warming
Authors: Lopes Cristiana , Rodrigues Andreia C. M. , Pires Sílvia F. S. , Campos Diana , Soares Amadeu M. V. M. , Vieira Hugo C. , Bordalo Maria D.
Published: November 2023

Microplastic pollution, global warming, and invasive species are known threats to marine biota, but the impact of their simultaneous exposure is still not well understood. This study investigated whether the toxic effects posed by the invasive red seaweed Asparagopsis armata exudate (2%) to the mussel Mytilus galloprovincialis are amplified by a 96 h exposure to increased temperature (24 °C) and polyethylene microplastics (PE-MPs, 1 mg/L). Biochemical (neurotoxicity, energy metabolism, oxidative stress, and damage) and physiological (byssal thread production) responses were evaluated. The number of produced byssus greatly decreased under concomitant exposure to all stressors. The antioxidant defences were depleted in the gills of mussels exposed to temperature rises and PE-MPs, regardless of exudate exposure, preventing oxidative damage. Moreover, the heat shock protein content tended to decrease in all treatments relative to the control. The increased total glutathione in the mussels’ digestive gland exposed to 24 °C, exudate, and PE-MPs avoided oxidative damage. Neurotoxicity was observed in the same treatment. In contrast, the energy metabolism remained unaltered. In conclusion, depending on the endpoint, simultaneous exposure to A. armata exudate, PE-MPs, and warming does not necessarily mean an amplification of their single effects. Studies focusing on the impact of multiple stressors are imperative to better understand the underlying mechanisms of this chronic exposure.
Polymorphism of Drug Resistance Genes dhfr and dhps in Plasmodium falciparum Isolates among Chinese Migrant Workers Who Returned from Ghana in 2013
Authors: Quan Hong , Yu Peng , Kassegne Kokouvi , Shen Hai-Mo , Chen Shen-Bo , Chen Jun-Hu
Published: November 2023

In 2013, an epidemic of falciparum malaria involving over 820 persons unexpectedly broke out in Shanglin County, Guangxi Zhuang Autonomous Region, China, after a large number of migrant workers returned from Ghana, where they worked as gold miners. Herein, we selected 146 isolates randomly collected from these patients to investigate the resistance characteristics of the parasite to sulfadoxine–pyrimethamine (SP) by screening mutations in the dhfr and dhps genes. All 146 isolates were successfully genotyped for dhps, and only 137 samples were successfully genotyped for dhfr. In the dhfr gene, point mutations occurred at three codons: 51 (83.2%, 114/137), 59 (94.9%, 130/137), and 108 (96.4%, 132/137). In the dhps gene, mutations occurred at four codons: 436 (36.3%, 53/146 for S436A, 0.7%, 1/146 for S436Y), 437 (95.2%, 139/146), 540 (3.4%, 5/146), and 613 (2.7%, 4/146). All 146 isolates had mutations in at least one codon, either within dhfr or dhps. Quadruple mutation I51R59N108/G437 (41.1%, 60/146) of partial or low resistance level was the most prevalent haplotype combination. Quintuple I51R59N108/G437E540 accounted for 2.1% (3/146). Sextuple I51R59N108/A436G437S613 was also found and accounted for 1.4% (2/146). A chronological assay incorporating two sets of resistance data from the studies of Duah and Amenga-Etego provided an overview of the resistance trend from 2003 to 2018. During this period, the results we obtained generally coincided with the total development tendency of SP resistance. It can be concluded that Plasmodium falciparum samples collected from Chinese migrant workers from Ghana presented prevalent but relatively partial or low resistance to SP. A chronological assay incorporating two sets of data around 2013 indicates that our results possibly reflect the SP resistance level of Ghana in 2013 and that the possibility of increased resistance exists. Therefore, reasonable drug use and management should be strengthened while also maintaining a continuous screening of resistance to SP. These findings also underscore the need to strengthen the prevention of malaria importation from overseas and focus on preventing its reintroduction and transmission in China.
Observational Detection of Higher-Order Secular Perturbations in Tight Hierarchical Triple Stars
Authors: Borkovits Tamás , Mitnyan Tibor
Published: November 2023

In this work, we search for observational evidence of higher-order secular perturbations in three eclipsing binaries. These are slightly eccentric binaries, and they form the inner pairs of tight, compact, hierarchical triple star systems. Simultaneously, we analyze the high-precision satellite (Kepler and TESS) light curves; eclipse timing variations; combined spectral energy distributions (through catalog passband magnitudes); and, where available, radial velocities of KICs 9714358, 5771589, and TIC 219885468. Besides the determination of the robust astrophysical and dynamical properties of the three systems, we find evidence that the observed unusual eclipse timing variations of KIC 9714358 are a direct consequence of the octupole-order secular eccentricity perturbations forced by unusual, resonant behavior between the lines of the apsides of the inner and outer orbital ellipses. We also show that, despite its evident cyclic eclipse depth variations, KIC 5771589 is an almost perfectly coplanar system (to within 0.3∘), and we explain the rapid eclipse depth variations with the grazing nature of the eclipses. Finally, we find that the inner pair of TIC 219885468 consists of two twin stars; hence, in this triple there are no octupole-order three-body perturbations. Moreover, we show that this triple is also coplanar on the same level as the former one, but due to its deep eclipses, it does not exhibit eclipse depth variations. We intend to follow this work up with further analyses and a quantitative comparison of the theoretical and the observed perturbations.
Improvement of the qmosRT-PCR Assay and Its Application for the Detection and Quantitation of the Three Serotypes of the Novel Oral Polio Vaccine in Stool Samples
Authors: Manukyan Hasmik , Tritama Erman , Wahid Rahnuma , Anstadt Jennifer , Konz John , Chumakov Konstantin , Laassri Majid
Published: November 2023

Recently, genetically stable novel OPVs (nOPV) were developed by modifying the genomes of Sabin viruses of conventional OPVs to reduce the risk of reversion to neurovirulence and therefore the risk of generating circulating vaccine-derived polioviruses. There is a need for specific and sensitive methods for the identification and quantification of nOPV viruses individually and in mixtures for clinical trials and potentially for manufacturing quality control and environmental surveillance. In this communication, we evaluated and improved the quantitative multiplex one-step reverse transcriptase polymerase chain reaction (qmosRT-PCR) assay for the identification and quantification of nOPV viruses in samples with different formulations and virus concentrations and in virus-spiked stool samples. The assay was able to specifically identify at least 1 log10 CCID50/mL of each serotype in the presence of the two other serotypes at high concentrations (6–7 log10 CCID50/mL) in the same sample. In addition, the lowest viral concentration that the assay was able to detect in stool samples was 17 CCID50/mL for nOPV1 and nOPV2 viruses and 6 CCID50/mL for nOPV3. We also found high correlation between the expected and observed (by qmosRT-PCR) concentrations of spiked viruses in stool samples for all three nOPV viruses, with R-squared values above 0.95. The analysis of samples collected from an nOPV2 clinical trial showed that 100% of poliovirus type 2 was detected and few samples showed the presence of type 1 and 3 residuals from previous vaccinations with bOPV (at least 4 weeks prior vaccination with nOPV2), confirming the high sensitivity of the method. The qmosRT-PCR was specific and sensitive for the simultaneous identification and quantification of all three nOPV viruses. It can be used as an identity test during the nOPV manufacturing process and in evaluation of virus excretion in nOPV clinical trials.
Intranasal Liposomal Formulation of Spike Protein Adjuvanted with CpG Protects and Boosts Heterologous Immunity of hACE2 Transgenic Mice to SARS-CoV-2 Infection
Authors: Russo Momtchilo , Mendes-Corrêa Maria Cássia , Lins Bruna B. , Kersten Victor , Pernambuco Filho Paulo C. A. , Martins Toni Ricardo , Tozetto-Mendoza Tânia Regina , Vilas Boas Lucy Santos , Gomes Brisa Moreira , Dati Livia Mendonça Munhoz , Duarte-Neto Amaro Nunes , Reigado Gustavo Roncoli , Frederico Ana Beatriz T. , de Brito e Cunha Danielle R. de A. , de Paula Anderson Vicente , da Silva José Igor G. , Vasconcelos Carlos F. Moreira , Chambergo Felipe S. , Nunes Viviane Abreu , Ano Bom Ana Paula Dinis , Castilho Leda R. , Martins Rodrigo A. P. , Hirata Mario Hiroyuki , Mirotti Luciana
Published: November 2023

Mucosal vaccination appears to be suitable to protect against SARS-CoV-2 infection. In this study, we tested an intranasal mucosal vaccine candidate for COVID-19 that consisted of a cationic liposome containing a trimeric SARS-CoV-2 spike protein and CpG-ODNs, a Toll-like receptor 9 agonist, as an adjuvant. In vitro and in vivo experiments indicated the absence of toxicity following the intranasal administration of this vaccine formulation. First, we found that subcutaneous or intranasal vaccination protected hACE-2 transgenic mice from infection with the wild-type (Wuhan) SARS-CoV-2 strain, as shown by weight loss and mortality indicators. However, when compared with subcutaneous administration, the intranasal route was more effective in the pulmonary clearance of the virus and induced higher neutralizing antibodies and anti-S IgA titers. In addition, the intranasal vaccination afforded protection against gamma, delta, and omicron virus variants of concern. Furthermore, the intranasal vaccine formulation was superior to intramuscular vaccination with a recombinant, replication-deficient chimpanzee adenovirus vector encoding the SARS-CoV-2 spike glycoprotein (Oxford/AstraZeneca) in terms of virus lung clearance and production of neutralizing antibodies in serum and bronchial alveolar lavage (BAL). Finally, the intranasal liposomal formulation boosted heterologous immunity induced by previous intramuscular vaccination with the Oxford/AstraZeneca vaccine, which was more robust than homologous immunity.
Upflow Direct Filtration and Downflow Direct Filtration: A Comparison with Emphasis on the Removal of Aerobic Spore-Forming Bacteria and Fluorescent Microspheres as Surrogates for Cryptosporidium Oocyst Removal
Authors: Pereira Álef Luan de Souza , Brandão Cristina Celia Silveira , Ginoris Yovanka Pérez , Alves Carla Patrícia Pereira
Published: November 2023

Monitoring the removal of Cryptosporidium oocysts in water treatment plants is a challenge, particularly in developing countries, and the use of surrogates has proven necessary. Two surrogates already investigated and recognized by the scientific community are aerobic spore-forming bacteria (ASFB) and fluorescent polystyrene microspheres (ME). In this context, this study evaluates and compares the performance of upflow direct filtration and downflow direct filtration, with emphasis on the removal of ASFB and ME as a surrogate of Cryptosporidium oocyst removal. Pilot filtration experiments were carried out with low turbidity Paranoá Lake water (average—3.7 NTU) with ASFB varying from 7 × 102 to 5.5 × 103 CFU/100 mL. In some experiments, water was spiked with microspheres, aiming for 105 ME/L. Two operational conditions were evaluated: (1) filters operating with the same filtration rate (5 m/h); (2) filters operating with the same flow rate of 59.41 L/h. In general, the downflow filter presented a slightly higher removal efficiency than the upflow filter but the differences were not considered statistically significant in most cases. The removal efficiency of microspheres (3 to 5 log) was higher than that of ASFB (1.2 to 4 log) in both filters, corroborating that the removal of ASFB is a conservative surrogate of the removal of Cryptosporidium.
Signal Spectrum Analysis of Sediment Water Impact of Hydraulic Turbine Based on ICEEMDAN-Wavelet Threshold Denoising Strategy
Authors: Bai Shufang , Zeng Yun , Dao Fang , Xiao Boyi , Li Xiang , Qian Jing
Published: November 2023

Studies show that sediment erosion is one of the main factors attributing to hydraulic turbine failure. The present paper represents an investigation into acoustic vibration signals generated by the water flow impacting the hydraulic turbine runner under three different operating conditions. Collected signals were denoised using the ICEEMDAN-wavelet threshold method, and then the spectral characteristics and sample entropy characteristics of the signals for the three operating conditions were analyzed. The results show that when clean water flows through the hydraulic turbine, the sample entropy reaches its smallest values and the dominant frequency component in the spectrogram is 59.39 Hz. When transitioning from clean water to the flood flow containing 2–4 mm sediment particles, the sample entropy is increasing and a high-frequency component higher than 59.39 Hz becomes the prominent frequency of the spectrogram. Meanwhile, the formation of high-frequency components increases with the sand-containing particle size. Based on the spectral characteristics and sample entropy characteristics of the acoustic vibration signals under different operating conditions, it can provide a reference for the sand avoidance operation of the hydraulic turbine during flood season. In addition, it provides a supplement to the existing hydraulic turbine condition’s monitoring systems and a new avenue for subsequent research on early warning of hydraulic turbine failure.
Groundwater Hydrogeochemical Processes and Potential Threats to Human Health in Fengfeng Coal Mining Area, China
Authors: Zhang Zhiqiang , Li Haixue , Zhang Fawang , Qian Jiazhong , Han Shuangbao , Dai Fenggang
Published: November 2023

The Fengfeng mining area is in the transition zone between the North China Plain and the Taihang Mountains, and groundwater is the main source of water supply in the district. Under the combined influence of human activities and natural geological conditions, the quality of different types of groundwater varies greatly, posing a potential threat to the safety of drinking water. In this study, hydrogeochemical processes in different types of groundwater were analyzed using multivariate statistical analysis methods with ion–ratio relationships, and a groundwater quality and health risk assessment model was developed. The research findings show that the main chemical components and TDS in the groundwater have obvious spatial distribution characteristics, i.e., the content of deep karst water (DKW) in the west is significantly lower than that of shallow pore water (SPW) in the east, and the hydrochemical type has changed from HCO3–Ca to SO4–Ca. The chemical components of SPW and DKW are mainly derived from silicates and carbonates, accompanied by weathering dissolution of sulphidic minerals, especially SPW. The chemical components of the groundwater was also influenced by the cation exchange reaction and human activities. The quality of the SPW was significantly worse than that of the DKW, and the nitrates in SPW carry a high non-carcinogenic risk, especially to children. The shallow pore water is not suitable for drinking water. This study can provide guidance on the safety of drinking water in the Fengfeng coal mining area and other areas with intensive industrial, mining, and agricultural activities.
Managing Transitions to Autonomous and Electric Vehicles: Scientometric and Bibliometric Review
Authors: Todorovic Milan , Aldakkhelallah Abdulaziz , Simic Milan
Published: November 2023

This paper presents a scientometric and bibliometric literature review of the research on transitions to autonomous and electric vehicles. We discuss the main characteristics, evolution, and various transitional issues, identifying potential trends for future research. The Scopus and WoS search for relevant research articles generated a corpus of 4693 articles, which we analyzed using VOSviewer visualization software. This result shows that the transition research is interdisciplinary, with 54 scientific areas identified. Analysis requires an understanding of the broader aspects of the automotive industry, trends related to sustainability, environment protection, road safety, public policies, market factors and other business, and legal and management issues. This study highlights the need for more research to address the challenges of this global transition in the automotive industry. Topics for future research are constant improvements in AI algorithms used in AVs, innovations in green energy sources, and storage solutions for EVs. This is leading to new innovative business models and platforms. Further to that, the conclusion is that the impact of the transition to a shared economy, the emergency of mobility as a service, and public acceptance of the technology have to be comprehensively considered. The vehicle of the future is seen as a smart electric car, running on green energy, and utilizing various levels of automation up to full autonomy.
Research into the Peculiarities of the Individual Traction Drive Nonlinear System Oscillatory Processes
Authors: Klimov Alexander V. , Ospanbekov Baurzhan K. , Keller Andrey V. , Shadrin Sergey S. , Makarova Daria A. , Furletov Yury M.
Published: November 2023

Auto-oscillations may occur in moving vehicles in the area where the tire interacts with the support base. The parameters of such oscillations depend on the sliding velocity in the contact patch. As they negatively affect the processes occurring in the electric drive and the mechanical transmission, reducing their energy efficiency, such processes can cause failures in various elements. This paper aims to conduct a theoretical study into the peculiarities of oscillatory processes in the nonlinear system and an experimental study of the auto-oscillation modes of an individual traction drive. It presents the theoretical basis used to analyze the peculiarities of oscillation processes, including their onset and course, the results of simulation mathematical modeling and the experimental studies into the oscillation phenomena in the movement of the vehicle towards the supporting base. The practical value of this study lies in the possibility to use the results in the development of algorithms for the exclusion of auto-oscillation phenomena in the development of vehicle control systems, as well as to use the auto-oscillation processes onset and course analysis methodology to design the electric drive of the driving wheels.
Multi-Mode Switching Control Strategy for IWM-EV Active Energy-Regenerative Suspension Based on Pavement Level Recognition
Authors: Zhou Zhigang , Shi Zhichong , Ding Xinqing
Published: November 2023

Aiming at the problems of poor overall vibration reduction and high energy consumption of in-wheel motor-driven electric vehicle (IWM-EV) active suspension on mixed pavement, a multi-mode switching control strategy based on pavement identification and particle swarm optimization is proposed. First, the whole vehicle dynamic model containing active energy-regenerative suspension and the reference model was established, and the sliding mode controller and PID controller designed, respectively, to suppress the vertical vibration of the vehicle and the in-wheel motor. Second, a road grade recognition model based on the dynamic travel signal of the suspension and the road grade coefficient was established to identify the road grade, and then the dynamic performance and energy-feedback characteristics of suspension were optimized by particle swarm optimization. According to the results of pavement identification, the optimal solution of the suspension controller parameters under each working mode was divided and selected to realize the switch of the suspension working mode. The simulation results show that the control strategy can accurately identify the grade of road surface under the condition of mixed road surface, and the ride index of the optimized active energy-regenerative suspension is obviously improved, while some energy is recovered.
BIOSTABILITY OF CEMENT COMPOSITES FROM DRY BUILDING MIXTURES
Authors:   Tambov State Technical University, ELCHISHCHEVA T.F. , EROFEEV V.T. ,   National Research Mordovia State University, MONASTYREV P.V. ,   Tambov State Technical University, ABRAMOVA E.N. ,   National Research Mordovia State University, AFONIN V.V. ,   National Research Mordovia State University, EROFEEVA I.V. ,   Moscow State University of Civil Engineering, ATMANZIN A.F. ,   National Research Mordovia State University
Published: November 2023

A study was made of the influence of a model biological environment of the products of the metabolism of filamentous fungi on the biostability of cement composites from industrial dry building mixes for outdoor and indoor work. The low resistance of samples without additional bioprotection to the influence of the biological environment was established. Relevant is the development of cement composites with biocidal additives to ensure resistance to biologically and chemically aggressive environments without reducing the strength properties. The degree of fouling of samples from various types of dry building mixtures in a model environment of metabolic products of filamentous fungi was determined. Eight composites of different composition were studied under the influence of 13 types of model medium. The stability of the samples was established at a concentration of medium components from 0 to 5% by weight. Tile adhesive "UNIS 2000", tile adhesive "Prospectors", putty "Prospectors", facade plaster "KNAUF" have fungus-resistant properties. Putty "CT29 Ceresit". Waterproofing "VodoStopGlims", plaster "IvsilGross" and self-leveling floor "Magma" are non-mushroom resistant. The most unfavorable concentrations of filamentous fungi metabolism products for the samples were revealed. The effectiveness of the use of polymer-based biocidal additives of the Teflex series (OOO SoftPROTECTOR, Russia) on the resistance of cement composites to biodegradation was revealed. The additives "Anti-Salt Wash", "For Metal" and "Universal" showed the greatest efficiency, their use provides fungi resistance and fungicidal properties of building materials.
THE SPECIFICS OF THE POST-WAR RECONSTRUCTION OF THE HISTORICAL CENTER OF VORONEZH (1943-1959)
Authors:   Voronezh State Technical University, ENIN A.E. , ZAPLAVNAYA A.E. ,   Voronezh State Technical University
Published: November 2023

This article discusses the aspects of the formation and modernization of historical morphotypes of the block development of the central part of Voronezh during the post-war reconstruction (1945-1950-ies). The hypothesis is put forward about the importance in the present architectural and urban studies of ontological knowledge of the main stages of modernization of the architectural and planning structure of the modern historical urban center, including in the process of creating the principles of its functional and spatial organization. The object of this study is thearchitectural and urban planning environment of the historical center of Voronezh that has developed by the time of the post-war reconstruction period. A systematic retrospective analysis of the architectural and planning structure of Voronezh is carried out: the external and internal factors determining the principles of reconstruction of the historical urban center during the post-war restoration of the USSR as a complex multilevel object of the "population and environment" type are identified and fixed in accordance with the identified factors of the boundaries of the study; the parameters of the studied territory are systematized in a certain time period at various hierarchical levels, and the fund of successive historical and urban values expressed in material, spatial and functional equivalents is determined. As a result of this study, the stable architectural and urban planning trends of spatial and functional modernization of the studied territory during the post-war reconstruction of Voronezh are determined, which are necessary for the organization of a correct reconstruction process at the present time. The historical-architectural and urban planning analysis carried out on the basis of historical-archival and bibliographic studies allowed us to form a typology of historical morphotypes of the city's buildings. Voronezh in the period of post-war reconstruction, as well as to identify extreme modernizations that carry a historical and cultural code. The system principles of the post-war reconstruction of the architectural and planning structure in two directions have been formed, differentiated on the basis of typological groups of planning elements of the functional and spatial organization of the urban center identified as a result of the systematic approach in the period under consideration.
Disease patterns in high-cost individuals with multimorbidity: a retrospective cross-sectional study in primary care
Authors: Soley-Bori Marina , Ashworth Mark , McGreevy Alice , Wang Yanzhong , Durbaba Stevo , Dodhia Hiten , Fox-Rushby Julia
Published: November 2023

Background

‘High-cost’ individuals with multimorbidity account for a disproportionately large share of healthcare costs and are at most risk of poor quality of care and health outcomes.

Aim

To compare high-cost with lower-cost individuals with multimorbidity and assess whether these populations can be clustered based on similar disease patterns.

Design and setting

A cross-sectional study based on 2019/2020 electronic medical records from adults registered to primary care practices (n= 41) in a London borough.

Method

Multimorbidity is defined as having ≥2 long-term conditions (LTCs). Primary care costs reflected consultations, which were costed based on provider and consultation types. High cost was defined as the top 20% of individuals in the cost distribution. Descriptive analyses identified combinations of 32 LTCs and their contribution to costs. Latent class analysis explored clustering patterns.

Results

Of 386 238 individuals, 101 498 (26%) had multimorbidity. The high-cost group (n= 20 304) incurred 53% of total costs and had 6833 unique disease combinations, about three times the diversity of the lower-cost group (n= 81 194). The trio of anxiety, chronic pain, and depression represented the highest share of costs (5%). High-cost individuals were best grouped into five clusters, but no cluster was dominated by a single LTC combination. In three of five clusters, mental health conditions were the most prevalent.

Conclusion

High-cost individuals with multimorbidity have extensive heterogeneity in LTCs, with no single LTC combination dominating their primary care costs. The frequent presence of mental health conditions in this population supports the need to enhance coordination of mental and physical health care to improve outcomes and reduce costs.
TRADE AND MONEY CIRCULATION OF ANCIENT GREECE
Authors:   Chernivtsi Institute of Trade and Economics of SUTE, Orehowskyi Wadym
Published: November 2023

The article is devoted to highlighting the main directions and features of trade and money circulation in Ancient Greece. In the introduction, the author notes that the Kingdom of Egypt and the state entities of Mesopotamia were the first centers of regional trade. A separate "branch" of the trade system of the Mediterranean was made up of numerous polises of Ancient Greece, which were essentially separate states. It was the sea spaces that played a major role in a Greek trade. The latter contributed to the formation, on the one hand, of a unique "Mediterranean world", and on the other - the Greeks became the creators of a universal civilization that had an extremely great influence on the formation of the future political, economic and cultural "face" of the world. Considering the main features of the economy of the inhabitants of Hellas, the author emphasizes that the main occupation of the Greeks was agriculture. The population was engaged in agriculture, sowing wheat and barley. But in the future, preference was given to viticulture, horticulture and olive growing. The further deepening of the division of labor is characteristic of craft manufacture. The main owner of the land was the polis (city-state), whose economic activity was based on the idea of autarky (self-sufficiency). Considering trade, the author of the article notes that the availability of convenient "access to the sea" of most of the polises contributed to the development of shipbuilding and navigation. The long coastal line facilitated cabotage transportation. Interpolis trade within the Aegean Sea was, to a large extent, under the control of the Athenian state. In addition, the Greeks conducted trade with other states of the Mediterranean world, and also sailed to the Black Sea. Grain remained the main import item during the existence of Greek civilization. It was mainly imported from: the Northern Black Sea region; the islands of Sicily, Cyprus and Euboea; Thrace and Egypt. Athens had to import wood as well as charcoal needed for silver ІСТОР ІЯ ЕКОНОМІКИ ТА ЕКОНОМІЧНОЇ ДУМКИ 10 Випуск IІ (90), 2023 smelting. Copper, gold, iron and tin were imported too. Among the export products, olive oil, marble, and painted vases prevailed. The most important Athenian resource was silver, which was exported in ingots or silver coins. Trade contributed to the development of money circulation and usury. The materials of the article can be useful for general and specialized courses on economic history, ancient history of international trade, for writing master's diploma, course theses.
AUDITING ACTIVITY UNDER THE STATE OF WAR: PROBLEMS, CHALLENGES, WAYS OF SOLUTION
Authors:   Chernivtsi Institute of Trade and Economics of SUTE, Mustetsa Iryna
Published: November 2023

The high degree of activity of the scientific community in the development of auditing in the war and post-war period in Ukraine, as well as the presence of debatable issues regarding problems and challenges in the direction of the development of audit in wartime conditions, as well as in the post-war period on the way to European integration, determined the choice of the topic, setting of the aim, tasks, subject and creation of the scientific research. The war caused significant destruction and, due to numerous migrations, caused a significant shortage of professionals in the field of internal and external auditing. The legislator made significant steps on the way to stabilize the situation with the activity of auditing entities, in particular, a number of normative acts were adopted, which should ensure the functioning of audit firms. Scientists were especially interested in the issue of conducting online audits using computer technologies and artificial intelligence. Leading foreign associations of auditors and professional accountants have developed instructions for Ukrainian auditors on how to work taking into account the state of war, because enterprises that continue to work in difficult conditions need constant support and consulting. ОБЛІК , АНАЛІЗ І АУДИТ 50 Випуск IІ (90), 2023 The article examined the state of audit activity in wartime conditions; it identified the main problems and the ways to solve them. The work had established main directions of the development of audit activity subjects on the way to European integration, including their normative regulation. In the process of carrying out the research, general scientific theoretical methods were used: system analysis - to clarify the main criteria of the research; induction method – at the stage of collecting, systematizing and processing information for research; deduction method - in the process of researching theoretical problems; abstract-logical method - for making theoretical generalizations and conclusions regarding the problems and challenges of audit activity in wartime conditions. The article examines the state and prospects of audit activity in modern economic conditions. The main problems faced by the auditors were considered, the main challenges for audit firms were determined, and the ways of solving isolated problems were established. It has been established that the legislation has regulated some issues related to auditing activities under martial law, as well as the main areas of auditor support in the post-war period. It is possible for Ukrainian audit firms to achieve further development and recovery in the post-war period due to well-considered management decisions, legislative support, as well as using online audits, computer technologies, and artificial intelligence. The audit system should be aimed at increasing trust in audits and auditors, which will make it possible to increase the investment attractiveness of our state.