bluuebunny/crossref_metadata_2025 huggingface dataset:
Resting Cysts of the Toxic Dinoflagellate Gymnodinium catenatum (Dinophyceae) Ubiquitously Distribute along the Entire Coast of China, with Higher Abundance in Bloom-Prone Areas
Authors: Liu Xiaohan , Tao Zhe , Liu Yuyang , Hu Zhangxi , Deng Yunyan , Shang Lixia , Lim Po-Teen , Chai Zhaoyang , Tang Ying-Zhong
Published: September 2024

Blooms of Gymnodinium catenatum have occurred occasionally in different areas of China and caused tremendous economic loss and even threatened human health. Not only is G. catenatum an important harmful-algal-bloom (HAB)-causing species, but also the only gymnodinioid dinoflagellate known to produce paralytic shellfish poisoning toxins (PSTs). Due to the germination of resting cysts, which often initiates blooms, the distribution and abundance of cysts in sediments and particularly the confirmation of cyst beds are important information for understanding and predicting dinoflagellate blooms. In this research, 199 sediment samples were collected from China’s coastal seas, ranging from the Beidaihe in the Bohai Sea (BS) to the southernmost sample from the Nansha Islands of the South China Sea (SCS). TaqMan quantitative PCR (qPCR) assays with species-specific primers and probes were developed to specifically detect the distribution and abundance of cysts in the 199 samples. The detection revealed that G. catenatum cysts were widely present in the sediments (126 of the 199 samples), with 93.55%, 74.65%, 42.37%, and 50% of the samples detected positively from the BS, YS, ECS and SCS, respectively, and covering the vast sea area from Nansha Islands to the Beidaihe area. The single-cyst morpho-molecular identification in the samples from Beidaihe confirmed the existence of G. catenatum cysts in the BS, and the positive detections of G. catenatum cysts using the qPCR methods. While G. catenatum cysts were widely distributed in all four seas of China, the average abundance was relatively low (1.0 cyst per gram of wet sediment). Three samples from the East China Sea (ECS), however, contained G. catenatum cysts at a relatively higher level (23 cysts g−1 wet sediment) than other sea areas, suggesting a pertinence of cyst abundance to the frequent occurrences of G. catenatum blooms in the area during recent years. Collectively, for G. catenatum being such an important toxic and HAB-causing species globally, the ubiquitous distribution of its cysts along the coastal waters of China and higher abundance in the bloom-prone areas warns us of a risk that cyst beds, although currently low in abundance, may seed HABs in any and many sea areas of China at any forthcoming year, and particularly those areas with records of frequent HABs outbreaks in the past.
Research on Response Strategies for Inland Waterway Vessel Traffic Risk Based on Cost-Effect Trade-Offs
Authors: Chen Yanyi , Ye Ziyang , Wang Tao , Tang Baiyuan , Wan Chengpeng , Zhang Hao , Li Yunpeng
Published: September 2024

Compared to maritime vessel traffic accidents, there is a scarcity of available, and only incomplete, accident data for inland waterway accidents. Additionally, the characteristics of different waterway segments vary significantly, and the factors affecting navigation safety risks and their mechanisms may also differ. Meanwhile, in recent years, extreme weather events have been frequent in inland waterways, and there has been a clear trend towards larger vessels, bringing about new safety hazards and management challenges. Currently, research on inland waterway navigation safety risks mainly focuses on risk assessment, with scarce quantitative studies on risk mitigation measures. This paper proposes a new method for improving inland waterway traffic safety, based on a cost-effectiveness trade-off approach to mitigate the risk of vessel traffic accidents. The method links the effectiveness and cost of measures and constructs a comprehensive cost-benefit evaluation model using fuzzy Bayesian and quantification conversion techniques, considering the reduction effects of risk mitigation measures under uncertain conditions and the various costs they may incur. Taking the upper, middle, and lower reaches of the Yangtze River as examples, this research evaluates key risk mitigation measures for different waterway segments and provides the most cost-effective strategies. Findings reveal that, even if different waterways share the same key risk sources, the most cost-effective measures vary due to environmental differences. Moreover, there is no inherent correlation between the best-performing measures in terms of benefits and the lowest-cost measures, nor are they necessarily recommended. The proposed method and case studies provide theoretical support for scientifically formulating risk mitigation measures in complex environments and offer guidance for inland waterway management departments to determine future key work directions.
Epigenetic Regulation of Fungal Secondary Metabolism
Authors: Zhang Yufei , Yu Wenbin , Lu Yi , Wu Yichuan , Ouyang Zhiwei , Tu Yayi , He Bin
Published: September 2024

Secondary metabolism is one of the important mechanisms by which fungi adapt to their living environment and promote survival and reproduction. Recent studies have shown that epigenetic regulation, such as DNA methylation, histone modifications, and non-coding RNAs, plays key roles in fungal secondary metabolism and affect fungal growth, survival, and pathogenicity. This review describes recent advances in the study of epigenetic regulation of fungal secondary metabolism. We discuss the way in which epigenetic markers respond to environmental changes and stimulate the production of biologically active compounds by fungi, and the feasibility of these new findings applied to develop new antifungal strategies and optimize secondary metabolism. In addition, we have deliberated on possible future directions of research in this field. A deeper understanding of epigenetic regulatory networks is a key focus for future research.
The Relationship between Surrogate Markers of Insulin Resistance and Occurrence of Colorectal Adenoma in Individuals under 50 Years Old: A Single-Center Retrospective Cross-Sectional Study
Authors: Choi Chi Hyeon , Moon Sang Yi , Lee Jong Yoon
Published: September 2024

(1) Background: Young-onset colorectal adenomas (YOAs) are precursors to early-onset colorectal cancer, a growing concern among individuals under 50 years old. This study investigated the association between surrogate markers of insulin resistance (IR) and YOAs occurrence. (2) Methods: A retrospective cross-sectional analysis was conducted on 4467 individuals aged 20 to 49 years who underwent their first screening colonoscopy at Dong-A University Hospital from 2018 to 2022. IR was assessed using the triglyceride–glucose (TyG) index, triglyceride-to-high-density lipoprotein cholesterol ratio (TG/HDL-C), and metabolic score for insulin resistance (METS-IR). (3) Results: Individuals with YOAs exhibited significantly higher median TyG index (8.51 ± 0.71 vs. 8.32 ± 0.61, p < 0.001), TG/HDL-C ratio (2.78 ± 3.05 vs. 2.12 ± 1.85, p < 0.001), and METS-IR (35.72 ± 8.37 vs. 33.44 ± 9.11, p < 0.001) values than controls. The adjusted odds ratios for YOAs were 1.064 (95% CI: 1.22–2.23, p = 0.021) for the TyG index, 1.067 (95% CI: 1.031–1.105, p < 0.001) for the TG/HDL-C ratio, and 1.011 (95% CI: 1.002–1.021, p = 0.023) for METS-IR values, indicating a strong association between higher IR marker values and the presence of YOAs. (4) Conclusions: Elevated IR marker values are strongly associated with the occurrence of YOAs in individuals under 50 years old.
Long-Run Trade Relationship between the U.S. and Canada: The Case of the Canadian Dollar with the U.S. Dollar
Authors: Gurrib Ikhlaas , Kamalov Firuz , Atayah Osama , Hemdan Dalia , Starkova Olga
Published: September 2024

This study investigates the long-run relationship between the U.S. dollar and the Canadian dollar by analyzing the bilateral exchange rate induced by nominal and real shocks. The methodology centers on a structural vector autoregressive (SVAR) model, including the analysis of impulse response and variance decomposition to account for the impact of nominal and real shocks on exchange rate movements. This study also decomposes real shocks into demand and supply factors from both Canada and the U.S. and compares their impacts on the nominal and real exchange rates. The results are compared to shocks driven by country-specific nominal factors. This study uses quarterly data from December 1972 to December 2023. The findings suggest that real shocks have a permanent impact on both the nominal and real exchange rates, compared to nominal shocks, which have a temporary impact. Country-specific real supply-side factors have a more significant impact than country-specific real demand-side factors. Country-specific nominal factors barely impacted the nominal and real exchange rates between the U.S. and Canada.
Iowa’s Annual Phosphorus Budget: Quantifying the Inputs and Outputs of Phosphorus Transport Processes
Authors: Anderson Elliot , Schilling Keith , Jones Christopher , Weber Larry , Wolter Calvin
Published: September 2024

Phosphorus (P) plays an integral part in Iowa’s economic and environmental activities through its role as an essential nutrient and waterborne pollutant. However, the amount of phosphorus transported through these activities has not been well quantified. This study estimates the annual mass of P entering and exiting Iowa’s landscape from 1998 to 2022 through seven transport pathways. Four input pathways (fertilizer application, manure production, industrial sources, and human sources) and three output pathways (harvesting, livestock grazing, and stream export) were quantified using various agricultural, economic, and water quality datasets. We also estimated the total mass of P present in the top 0.61 m layer of Iowa’s landscape using results from a statewide soil sampling survey. The harvest component was the largest, with annual values consistently above 200 million kg. This was followed by the fertilizer and manure components, with annual values near 100 million kg. The other components were much smaller; the mean grazing and stream export values were 15 and 19 million kg, respectively, and human and industrial sources were less than 4 million kg. Stream export was the most dynamic pathway, with the largest coefficient of variation (0.59). The net P budget (inputs–outputs) was negative in 20 of the 25 years assessed, indicating that Iowa typically runs a P deficit. A trend analysis revealed that the manure, human, industry, and harvesting components increased across the 1998–2022 period while the grazing component decreased. The mass of P in Iowa’s top layer of soil was 81.5 billion kg—orders of magnitude larger than any individual budget component. This analysis provides a new perspective on P transport pathways in Iowa and may help inform policymakers as they make decisions on the many activities involving P.
Permanent Human Occupation of the Western Tibetan Plateau in the Early Holocene
Authors: Lu Hongliang , Li Ziyan
Published: September 2024

Archaeological investigations worldwide have focused on when and how humans permanently settled in high-altitude environments. Recent evidence from Xiada Co, Qusongguo, and Dingzhonghuzhuzi in western Tibet, where lithic artifacts and radiocarbon dates with original deposits were first accessed, provides new insights into human activities in this extreme environment during the early Holocene. This paper examines the mobility and land-use patterns of foragers in western Tibet from the perspectives of lithic analysis. Assemblages from three sites suggest homogenous technologies and raw material use, as well as potential interaction network of hunter-gatherers within the plateau during the early Holocene. It further argues that the material exponents and travel cost models of site location supported permanent occupation of the western Tibetan Plateau in this period.
Transformation from Rural Industrialization to Suburban Industrialization in Guangzhou: Pattern and Mechanism
Authors: Zhang Jing , Xiao Weiye , Chen Wen
Published: September 2024

Analyzing the trajectory and mechanism of rural industrial change is important for understanding urban–rural integration and facilitating rural revitalization. Based on the data of industrial enterprises in 1112 administrative villages of Guangzhou, China, from 1978 to 2020, we identify the evolution trend of rural industry by investigating the spatial–temporal dynamics of industrial changes in rural areas. An extended triple-process framework incorporating urbanization and greenization was employed to unravel the underlying mechanism of the trajectory of rural industrialization. The results highlight the transformation from rural to suburban industrialization. In the past twenty years, rapid urbanization has contributed to the establishment of development zones. The agglomeration economy has led to a higher concentration of manufacturing industries in these development zones rather than rural areas. The eco-friendly development has resulted in a green transition in rural areas, further restricting the growth of traditional rural industries. Our analysis provides a nuanced picture of Guangzhou’s spatial–temporal dynamics of rural and suburban industrialization. Meanwhile, it emphasizes the importance of urbanization and greenization in explaining the recent transformation of industrialization in China.
Comparative Study of Different Respiratory Muscle Training Methods: Effects on Cardiopulmonary Indices and Athletic Performance in Elite Short-Track Speedskaters
Authors: Kowalski Tomasz , Klusiewicz Andrzej , Rębiś Kinga , Wilk Adrian , Starczewski Michał
Published: September 2024

Respiratory muscle training (RMT) improves endurance performance, balance, and ability to repeat high-intensity exercise bouts, providing a rationale to be applied in short-track speedskating. To establish a preferable RMT method for short-track speedskating, the influence of inspiratory pressure threshold loading (IPTL) and voluntary isocapnic hyperpnoea (VIH) on cardiopulmonary indices and athletic performance was investigated. Sixteen elite short-track speedskaters completed 6 weeks of RMT based on IPTL or VIH. Wingate Anaerobic Tests (WAnTs), cardiopulmonary exercise tests (CPETs), spirometry assessments, and on-ice time trials were performed before and after RMT intervention. Repeated measures ANOVA was used to assess the differences between each method’s influence. No statistically significant (p > 0.05) differences between RMT methods were found in performance during the WAnT, CPET, or specific on-ice time trials. Spirometry measures were similar between both methods. Significant effects were found for the interaction between maximum breathing frequency during CPET (BFmax) and method (p = 0.009), as well as for the interaction between BFMax, method, and sex (p = 0.040). BFmax decreased for IPTL and increased for VIH. The interaction between method and sex revealed that BFmax increased only in males performing VIH. Our findings suggest that IPTL and VIH lead to analogous effects in the study participants, highlighting a negligible practical disparity in the impact of different RMT methods in elite short-track speedskaters.
Vacuum Erection Device Plus Once-Daily Tadalafil Improve Clinical Outcomes after Extracorporeal Shock Wave Therapy in Men Affected by Erectile Dysfunction Associated with Peyronie’s Disease
Authors: Dell’Atti Lucio , Slyusar Viktoria , Ronchi Piero , Cambise Chiara
Published: September 2024

Background: The purpose of this study is to examine the combination of the mechanical effects of penile therapy with vacuum erection devices (VEDs) plus PDE5i, which improve clinical outcomes after extracorporeal shockwave therapy (ESWT) in men affected by erectile dysfunction (ED) associated with Peyronie’s disease (PD). Methods: A total of 153 medical records of patients affected by PD in stable stage with ED and treated with ESWT were divided into two groups. Group A (GA) included 72 men treated with ESWT, mechanical stretching with VEDs and PDE5ì (Tadalafil 5 mg), and Group B (GB) included 81 men who received only ESWT plus Tadalafil 5 mg with the same protocol of GA. The patients in both groups were assessed at baseline and follow-up for erectile function, painful erections, penile plaque size, and penile curvature. The results were evaluated at baseline and 3, 6, and 12 months after the treatments. Results: Three months after the treatment, GA patients had a reduction in penile curvature degree from a mean ± SD of 33.91 ± 8.34° at baseline to a mean ± SD of 19.46 ± 7.15° after 12 months, whereas pain in an erection or during intercourse was resolved completely in 88.9% of the patients. The mean ± SD IIEF-15 score of patients affected by severe/moderate ED further improved significantly in the GA group (p < 0.001) after 3, 6, and 12 months of treatment. There were no permanent adverse sequelae after treatments. Conclusions: The regular use of a VED plus Tadalafil in patients who had undergone ESWT significantly provided more benefit in patients with PD in terms of penile deformity, pain, and erectile function.
A Study on the Mechanisms and Performance of a Polyvinyl Alcohol-Based Nanogenerator Based on the Triboelectric Effect
Authors: Sun Wuliang , Dong Junhui , Gao Xiaobo , Chen Baodong , Nan Ding
Published: September 2024

Polyvinyl alcohol (PVA), a versatile polymer, is extensively used across many industries, such as chemicals, food, healthcare, textiles, and packaging. However, research on applying PVA to triboelectric nanogenerators (TENGs) remains limited. Consequently, we chose PVA as the primary material to explore its contact electrification mechanisms at the molecular level, alongside materials like Polyethylene (PE), Polyvinylidene fluoride (PVDF), and Polytetrafluoroethylene (PTFE). Our findings show that PVA has the highest band gap, with the smallest band gap occurring between the HOMO of PVA and the LUMO of PTFE. During molecular contact, electron transfer primarily occurs in the outermost layers of the molecules, influenced by the functional groups of the polymers. The presence of fluorine atoms enhances the electron transfer between PVA and PTFE to maximum levels. Experimental validation confirmed that PVA and PTFE contact yields the highest triboelectric performance: VOC of 128 V, ISC of 2.83 µA, QSC of 82 nC, and an output power of 384 µW. Moreover, P-TENG, made of PVA and PTFE, was successfully applied in self-powered smart devices and monitored human respiration and bodily movements effectively. These findings offer valuable insights into using PVA in triboelectric nanogenerator technologies.
Processing of Layered Composite Products Manufactured on the Basis of Bioresin Reinforced with Flax Fabric Using Milling Technology
Authors: Frącz Wiesław , Ryzińska Grażyna , Skoczylas Leszek , Bąk Łukasz , Janowski Grzegorz
Published: September 2024

In this work, a laminate based on bioresin and natural fibers was produced. Flax fabric was selected as the natural fiber. The biocomposite was subjected to strength tests. Stress–strain characteristics and strength indicators were determined. The workability of the laminate produced was also tested using milling technology. The tests were carried out using five carbide shank cutters for different purposes. The cutters with the geometry used in the processing of polymer materials and composites, general purpose cutters, and cutters with the geometry for aluminum and with different numbers of blades were analyzed. In order to obtain information on the workability of the prepared material, machining tests with different configurations of technological parameters were carried out. For each cutter, the effect of cutting speed and feed rate on the quality of the machined surface was tested. Due to the small thickness of the laminate, the machining was carried out in one pass, as a result of which the cutting depth in each case was constant. Changes in cutting speed and feed were evenly distributed over five levels. The quality of machining was assessed in two stages. The first stage included a visual assessment of the machined surface, involving a preliminary qualification of the machining parameters. The criterion was the amount of chips, frays, burrs, etc., remaining after machining that adhered to the surface. The next stage was the measurement of the geometric structure of the surface, during which the roughness parameters were analyzed using an optical microscope with a roughness analysis attachment. Quantitative analysis was performed for the best quality composite surfaces from each measurement series. The studies showed a dependence of the quality of machining on the technological parameters used. High tool speed, regardless of the type, especially at low feed, led to the sticking of chips, which had a very delicate form. In turn, low tool speed and high feed, due to the chip thickness, favored the formation of burrs. Machining with different types of tools showed that the process progresses better for tools with sharp blade geometry. Machining with a regular and polished cutter did not show any differences in the scope of the process progress.
Synthesis of Fe2O3/TiO2 Photocatalytic Composites for Methylene Blue Degradation as a Novel Strategy for High-Value Utilisation of Iron Scales
Authors: Liu Li , Cui Zhenghao , Feng Bo , Sui Mengjing , Huang Huaqin , Wu Zhaoyang
Published: September 2024

In this study, novel Fe2O3/TiO2 photocatalytic composites were synthesised by combining traditional oxidation roasting with the sol-gel method, using low-cost metallurgical waste (iron scales) as the raw material. The characterisation results revealed that the oxidised iron scales could be transformed into high-purity and porous Fe2O3 particles through oxidation roasting, thereby providing additional sites for the adsorption process and thus serving as an effective carrier for TiO2-based photocatalytic materials. During the sol-gel process, TiO2 was loaded onto the synthesised Fe2O3 particles, generating core-shell heterostructure Fe2O3/TiO2 photocatalytic composites. Under visible light irradiation for 90 min, the Fe2O3/TiO2 photocatalytic composites achieved a remarkable methylene blue removal rate (97.71%). This reaction process followed the quasi-first-order kinetic model with a rate constant of 0.038 min−1. The results have demonstrated that this combination of various components in the Fe2O3/TiO2 photocatalytic composites improved the adsorption, light utilisation, and charge separation effect of the photocatalysts. Moreover, the material exhibited favourable stability and recyclability, making it a decent candidate for the treatment of wastewater from the biochemical industry. Therefore, this study provides a new strategy for improving the photocatalytic activity of TiO2 and expanding the high value-added utilisation of iron scales.
Optimization of Tool Wear and Cutting Parameters in SCCO2-MQL Ultrasonic Vibration Milling of SiCp/Al Composites
Authors: Zhang Huiping , Wang Bowen , Qu Liqiang , Wang Xinran
Published: September 2024

Silicon carbide particle-reinforced aluminum matrix (SiCp/Al) composites are significant lightweight metal matrix composites extensively utilized in precision instruments and aerospace sectors. Nevertheless, the inclusion of rigid SiC particles exacerbates tool wear in mechanical machining, resulting in a decline in the quality of surface finishes. This work undertakes a comprehensive investigation into the problem of tool wear in SiCp/Al composite materials throughout the machining process. Initially, a comprehensive investigation was conducted to analyze the effects of cutting velocity vc, feed per tooth fz, milling depth ap, and milling width ae on tool wear during high-speed milling under SCCO2-MQL (Supercritical Carbon Dioxide Minimum Quantity Lubrication) ultrasonic vibration conditions. The results show that under the condition of SCCO2-MQL ultrasonic vibration, proper control of milling parameters can significantly reduce tool wear, extend tool service life, improve machining quality, and effectively reduce blade breakage and spalling damage to the tool, reduce abrasive wear and adhesive wear, and thus significantly improve the durability of the tool. Furthermore, a prediction model for tool wear was developed by employing the orthogonal test method and multiple linear regression. The model’s relevance and accuracy were confirmed using F-tests and t-tests. The results show that the model can effectively predict tool wear, among which cutting velocity vc and feed rate fz are the key parameters affecting the prediction accuracy. Finally, a genetic algorithm was used to optimize the milling parameters, and the optimal parameter combination (vc = 60.00 m/min, fz = 0.08 mm/z, ap = 0.20 mm) was determined, and the optimized milling parameters were tested. Empirical findings suggest that the careful selection of milling parameters can significantly mitigate tool wear, extend the lifespan of the tool, and enhance the quality of the surface. This work serves as a significant point of reference for the processing of SiCp/Al composite materials.
Analysis of Scraper Conveyor Chain Dynamics under Falling Coal Impact Conditions
Authors: Jiang Shoubo , Zhang Yuqi , Zeng Qingliang , Chen Shaojie , Qu Wei , Zhang Hongwei
Published: September 2024

The scraper conveyor, essential for mechanized mining, operates in harsh underground environments and is subjected to severe impact loads from coal and rock falls. Such conditions can cause chain jamming, breakage, and other malfunctions, necessitating a detailed study of the system’s dynamic behavior under impact conditions. This study investigates the dynamic characteristics of a scraper conveyor’s chain drive system using a coupled ADAMS-EDEM simulation model. The model analyzes the effects of loaded coal piles on the conveyor’s dynamics during normal and impact conditions. Simulations show that loaded coal piles excite the scraper’s acceleration and sprocket rotation, with the greatest impact in the scraper’s running direction. Longitudinal impact and contact forces on the chain ring are more significant than in other directions under both no-load and loaded conditions. A strong linear relationship exists between the falling coal mass and longitudinal impact force. The coal pile causes prominent longitudinal vibration excitation while inhibiting the overall vibration of the chain drive system to some extent. The findings provide insights for identifying failure-prone areas under impact conditions and offer theoretical guidance for optimizing scraper conveyor design. This enhances mining efficiency and safety in coal operations.
Third-Order Noncanonical Neutral Delay Differential Equations: Nonexistence of Kneser Solutions via Myshkis Type Criteria
Authors: Nithyakala Gunasekaran , Chatzarakis George E. , Ayyappan Govindasamy , Thandapani Ethiraju
Published: September 2024

The purpose of this paper is to add some new asymptotic and oscillatory results for third-order neutral delay differential equations with noncanonical operators. Without assuming any extra conditions, by using the canonical transform technique, the studied equation is changed to a canonical type equation, and this reduces the number of classes of nonoscillatory solutions into two instead of four. Then, we obtain Myshkis type sufficient conditions for the nonexistence of Kneser type solutions for the studied equation. Finally, employing these newly obtained criteria, we provide conditions for the oscillation of all solutions of the studied equation. Examples are presented to illustrate the importance and the significance of the main results.
Applications of Generalized Hypergeometric Distribution on Comprehensive Families of Analytic Functions
Authors: Al-Hawary Tariq , Frasin Basem , Aldawish Ibtisam
Published: September 2024

A sequence of n trials from a finite population with no replacement is described by the hypergeometric distribution as the number of successes. Calculating the likelihood that factory-produced items would be defective is one of the most popular uses of the hypergeometric distribution in industrial quality control. Very recently, several researchers have applied this distribution on certain families of analytic functions. In this study, we provide certain adequate criteria for the generalized hypergeometric distribution series to be in two families of analytic functions defined in the open unit disk. Furthermore, we consider an integral operator for the hypergeometric distribution. Some corollaries will be implied from our main results.
Efficient Study on Westervelt-Type Equations to Design Metamaterials via Symmetry Analysis
Authors: Izgi Zehra Pinar , Mohammed Pshtiwan Othman , Agarwal Ravi P. , Yousif Majeed A. , Lupas Alina Alb , Abdelwahed Mohamed
Published: September 2024

Metamaterials have emerged as a focal point in contemporary science and technology due to their ability to drive significant innovations. These engineered materials are specifically designed to couple the phenomena of different physical natures, thereby influencing processes through mechanical or thermal effects. While much of the recent research has concentrated on frequency conversion into electromagnetic waves, the field of acoustic frequency conversion still faces considerable technical challenges. To overcome these hurdles, researchers are developing metamaterials with customized acoustic properties. A key equation for modeling nonlinear acoustic wave phenomena is the dissipative Westervelt equation. This study investigates analytical solutions using ansatz-based methods combined with Lie symmetries. The approach presented here provides a versatile framework that is applicable to a wide range of fields in metamaterial design.
Solution of Inverse Photoacoustic Problem for Semiconductors via Phase Neural Network
Authors: Dragas Milica , Galovic Slobodanka , Milicevic Dejan , Suljovrujic Edin , Djordjevic Katarina
Published: September 2024

The inverse photoacoustic problem is an ill-posed mathematical physics problem. There are many methods of solving the inverse photoacoustic problem, from parameter reduction to the development of complex regularization algorithms. The idea of this work is that semiconductor physical properties are determined from phase characteristic measurements because phase measurements are more sensitive than amplitude measurements. To solve the inverse photoacoustic problem, the thermoelastic properties and thickness of the sample are estimated using a neural network approach. The neural network was trained on a large database of photoacoustic phases calculated from a theoretical Si n-type model in the range of 20 Hz to 20 kHz, to which random Gaussian noise was applied. It is shown that in solving the inverse photoacoustic problem, high accuracy and precision can be achieved by applying phase measurement and neural network approaches. This study showed that a multi-parameter inverse problem can be solved using phase networks.
Theoretical Results on Positive Solutions in Delta Riemann–Liouville Setting
Authors: Mohammed Pshtiwan Othman , Agarwal Ravi P. , Yousif Majeed A. , Al-Sarairah Eman , Lupas Alina Alb , Abdelwahed Mohamed
Published: September 2024

This article primarily focuses on examining the existence and uniqueness analysis of boundary fractional difference equations in a class of Riemann–Liouville operators. To this end, we firstly recall the general solution of the homogeneous fractional operator problem. Then, the Green function to the corresponding fractional boundary value problems will be reconstructed, and homogeneous boundary conditions are used to find the unknown constants. Next, the existence of solutions will be studied depending on the fixed-point theorems on the constructed Green’s function. The uniqueness of the problem is also derived via Lipschitz constant conditions.
Orthogonal Stability and Solution of a Three-Variable Functional Equation in Extended Banach Spaces
Authors: Jakhar Jagjeet , Sharma Shalu , Jakhar Jyotsana , Yousif Majeed A. , Mohammed Pshtiwan Othman , Lupas Alina Alb , Chorfi Nejmeddine
Published: September 2024

This manuscript introduces a novel three-variable cubic functional equation and derives its general solution. Employing both the direct and fixed-point methods, we investigate the orthogonal stability of this equation within the frameworks of quasi-β-Banach spaces and multi-Banach spaces. Additionally, the study explores the stability of the equation in various extended Banach spaces and provides a specific example illustrating the absence of stability in certain cases.
Fixed-Point and Random Fixed-Point Theorems in Preordered Sets Equipped with a Distance Metric
Authors: Baranwal Himanshu , Bisht Ravindra Kishor , Chand Arya Kumar Bedabrata , Yao Jen-Chih
Published: September 2024

This paper explores fixed points for both contractive and non-contractive mappings in traditional b-metric spaces, preordered b-metric spaces, and random b-metric spaces. Our findings provide insights into the behavior of mappings under various constraints and extend our approach to include coincidence and common fixed-point theorems in these spaces. We present new examples and graphical representations for the first time, offering novel results and enhancing several related findings in the literature, while broadening the scope of earlier works of Ran and Reurings, Nieto and Rodríguez-López, Górnicki, and others.
Study on Single-Machine Common/Slack Due-Window Assignment Scheduling with Delivery Times, Variable Processing Times and Outsourcing
Authors: Bai Bing , Wei Cai-Min , He Hong-Yu , Wang Ji-Bo
Published: September 2024

Single-machine due-window assignment scheduling with delivery times and variable processing times is investigated, where the variable processing time of a job means that the processing time is a function of its position in a sequence and its resource allocation. Currently, there are multiple optimization objectives for the due-window assignment problem, and there is a small amount of research on optimization problems where the window starting time, the rejected cost and the optimal scheduling are jointly required. The goal of this paper is to minimize the weighed sum of scheduling cost, resource consumption cost and outsourcing measure under the optional job outsourcing (rejection). Under two resource allocation models (i.e., linear and convex resource allocation models), the scheduling cost is the weighted sum of the number of early–tardy jobs, earliness–tardiness penalties and due-window starting time and size, where the weights are positional-dependent. The main contributions of this paper include the study and data simulation of single-machine scheduling with learning effects, delivery times and outsourcing cost. For the weighed sum of scheduling cost, resource consumption cost and outsourcing measure, we prove the polynomial solvability of the problem. Under the common and slack due-window assignments, through the theoretical analysis of the optimal solution, we reveal that four problems can be solved in O(n6) time, where n is the number of jobs.
Imputing Missing Data in One-Shot Devices Using Unsupervised Learning Approach
Authors: So Hon , Ling Man , Balakrishnan Narayanaswamy
Published: September 2024

One-shot devices are products that can only be used once. Typical one-shot devices include airbags, fire extinguishers, inflatable life vests, ammo, and handheld flares. Most of them are life-saving products and should be highly reliable in an emergency. Quality control of those productions and predicting their reliabilities over time is critically important. To assess the reliability of the products, manufacturers usually test them in controlled conditions rather than user conditions. We may rely on public datasets that reflect their reliability in actual use, but the datasets often come with missing observations. The experimenter may lose information on covariate readings due to human errors. Traditional missing-data-handling methods may not work well in handling one-shot device data as they only contain their survival statuses. In this research, we propose Multiple Imputation with Unsupervised Learning (MIUL) to impute the missing data using Hierarchical Clustering, k-prototype, and density-based spatial clustering of applications with noise (DBSCAN). Our simulation study shows that MIUL algorithms have superior performance. We also illustrate the method using datasets from the Crash Report Sampling System (CRSS) of the National Highway Traffic Safety Administration (NHTSA).
Rayleigh Waves in a Thermoelastic Half-Space Coated by a Maxwell–Cattaneo Thermoelastic Layer
Authors: Chiriţă Stan , D’Apice Ciro
Published: September 2024

This paper investigates the propagation of in-plane surface waves in a coated thermoelastic half-space. First, it investigates a special case where the surface layer is described by the Maxwell–Cattaneo thermoelastic approach, while the half-space is filled by a thermoelastic material described by the classical Fourier law for the heat flux. The contact between the layer and the half-space is assumed to be welded, i.e., the displacements and the temperature, as well as the stresses and the heat flux are continuous through the interface of the layer and the half-space. The boundary and continuity conditions of the problem are formulated and then the exact dispersion relation of the surface waves is established. An illustrative numerical simulation is presented for the case of an aluminum thermoelastic layer coating a thermoelastic copper half-space, highlighting important aspects regarding the propagation of Rayleigh waves in such structures. The exact effective boundary conditions at the interface are also established replacing the entire effect of the layer on the half-space. The general case of the problem is also investigated when both the surface layer and the half-space are described by the Maxwell–Cattaneo thermoelasticity theory. This study helps to further understand the propagation characteristics of elastic waves in layered structures with thermal effects described by the Maxwell–Cattaneo approach.
Enhancing Autism Spectrum Disorder Classification with Lightweight Quantized CNNs and Federated Learning on ABIDE-1 Dataset
Authors: Gupta Simran , Bhuiyan Md. Rahad Islam , Chowa Sadia Sultana , Montaha Sidratul , Rahman Rashik , Mehedi Sk. Tanzir , Rahman Ziaur
Published: September 2024

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that presents significant diagnostic challenges due to its varied symptoms and nature. This study aims to improve ASD classification using advanced deep learning techniques applied to neuroimaging data. We developed an automated system leveraging the ABIDE-1 dataset and a novel lightweight quantized one-dimensional (1D) Convolutional Neural Network (Q-CNN) model to analyze fMRI data. Our approach employs the NIAK pipeline with multiple brain atlases and filtering methods. Initially, the Regions of Interest (ROIs) are converted into feature vectors using tangent space embedding to feed into the Q-CNN model. The proposed 1D-CNN is quantized through Quantize Aware Training (QAT). As the quantization method, int8 quantization is utilized, which makes it both robust and lightweight. We propose a federated learning (FL) framework to ensure data privacy, which allows decentralized training across different data centers without compromising local data security. Our findings indicate that the CC200 brain atlas, within the NIAK pipeline’s filt-global filtering methods, provides the best results for ASD classification. Notably, the ASD classification outcomes have achieved a significant test accuracy of 98% using the CC200 and filt-global filtering techniques. To the best of our knowledge, this performance surpasses previous studies in the field, highlighting a notable enhancement in ASD detection from fMRI data. Furthermore, the FL-based Q-CNN model demonstrated robust performance and high efficiency on a Raspberry Pi 4, underscoring its potential for real-world applications. We exhibit the efficacy of the Q-CNN model by comparing its inference time, power consumption, and storage requirements with those of the 1D-CNN, quantized CNN, and the proposed int8 Q-CNN models. This research has made several key contributions, including the development of a lightweight int8 Q-CNN model, the application of FL for data privacy, and the evaluation of the proposed model in real-world settings. By identifying optimal brain atlases and filtering methods, this study provides valuable insights for future research in the field of neurodevelopmental disorders.
Human Activity Recognition from Accelerometry, Based on a Radius of Curvature Feature
Authors: Cavita-Huerta Elizabeth , Reyes-Reyes Juan , Romero-Ugalde Héctor M. , Osorio-Gordillo Gloria L. , Escobar-Jiménez Ricardo F. , Alvarado-Martínez Victor M.
Published: September 2024

Physical activity recognition using accelerometry is a rapidly advancing field with significant implications for healthcare, sports science, and wearable technology. This research presents an interesting approach for classifying physical activities using solely accelerometry data, signals that were taken from the available “MHEALTH dataset” and processed through artificial neural networks (ANNs). The methodology involves data acquisition, preprocessing, feature extraction, and the application of deep learning algorithms to accurately identify activity patterns. A major innovation in this study is the incorporation of a new feature derived from the radius of curvature. This time-domain feature is computed by segmenting accelerometry signals into windows, conducting double integration to derive positional data, and subsequently estimating a circumference based on the positional data obtained within each window. This characteristic is computed across the three movement planes, providing a robust and comprehensive feature for activity classification. The integration of the radius of curvature into the ANN models significantly enhances their accuracy, achieving over 95%. In comparison with other methodologies, our proposed approach, which utilizes a feedforward neural network (FFNN), demonstrates superior performance. This outperforms previous methods such as logistic regression, which achieved 93%, KNN models with 90%, and the InceptTime model with 88%. The findings demonstrate the potential of this model to improve the precision and reliability of physical activity recognition in wearable health monitoring systems.
Sunitinib in Patients with Metastatic Renal Cell Carcinoma with Favorable Risk: Be Aware of PD-L1 Expression
Authors: Tsimafeyeu Ilya
Published: September 2024

The treatment landscape for metastatic renal cell carcinoma (RCC) has advanced significantly with first-line immunotargeted therapy combinations. However, no statistically significant differences were observed in the cohort of patients with favorable risk and some oncologists continue to use sunitinib in these patients. PD-L1 expression has emerged as a negative prognostic factor in RCC, particularly in sunitinib-treated patients, where higher PD-L1 levels are linked to worse outcomes. This article discusses the potential risks associated with the use of sunitinib in PD-L1-positive patients.
Achieving Superior Ductility at High Strain Rate in a 1.5 GPa Ultrahigh-Strength Steel without Obvious Transformation-Induced Plasticity Effect
Authors: Lu Yao , Ma Tianxing , Liang Zhiyuan , Liu Li
Published: September 2024

The development of ultrahigh-strength steels with good ductility is crucial for improving the crashworthiness of automobiles. In the present work, the mechanical responses and deformation behaviors of 1.5 GPa ultrahigh-strength steel were systematically investigated over a wide range of strain rates, from 10−3 s−1 to 103 s−1. The yield strength and tensile elongation at quasi-static strain rate (10−3 s−1) were 1548 MPa and 20%, respectively. The yield strength increased to 1930 MPa at an extremely high strain rate (103 s−1), and the steel maintained excellent ductility, with values as high as 17%. It was found that the prevailing of the transformation-induced plasticity (TRIP) effect at quasi-static condition resulted in the formation of fresh martensite. This produced strong hetero-deformation-induced (HDI) stress and strain partitioning, contributing to the enhancement of strain hardening. The TRIP effect is remarkably suppressed under high strain rates, and thus the retained austenite with excellent deformation ability sustains the subsequent deformation, leading to superior ductility when the TRIP effect and HDI strengthening are retarded. Ultrahigh-strength steel with great strength–ductility combination over a wide range of strain rates has great potential in improving component performance while reducing vehicle weight.
Production of Spheroidized Micropowders of W-Ni-Fe Pseudo-Alloy Using Plasma Technology
Authors: Samokhin Andrey , Alekseev Nikolay , Dorofeev Aleksey , Fadeev Andrey , Sinaiskiy Mikhail
Published: September 2024

The process of obtaining powders from the 5–50 μm fraction of a W-Ni-Fe system consisting of particles with predominantly spherical shapes was investigated. Experimental studies on the plasma–chemical synthesis of a nanopowder composed of WNiFe-90 were carried out in a plasma reactor with a confined jet flow. A mixture of tungsten trioxide, nickel oxide, and iron oxide powders interacted with a flow of hydrogen-containing plasma generated in an electric-arc plasma torch. The parameters of the spray-drying process and the composition of a suspension consisting of WNiFe-90 nanoparticles were determined, which provided mechanically strong nanopowder microgranules with a rounded shape and a homogeneous internal structure that contained no cavities. The yield of the granule fraction under 50 μm was 60%. The influence of the process parameters of the plasma treatment of the nanopowder microgranules in the thermal plasma flow on the degree of spheroidization and the microstructure of the obtained particles, seen as their bulk density and fluidity, was established. It was shown that the plasma spheroidization of the microgranules of the W-Ni-Fe system promoted the formation of a submicron internal structure in the obtained spherical particles, which were characterized by an average tungsten grain size of 0.7 μm.