bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasound Evaluation of Gastric Emptying and Comparison with Patient-Reported Risk Factors in Elective Surgical Patients
Authors: Inan Sezgin , Erdivanli Basar
Published: January 2025

Background/Objectives: Despite standard preoperative fasting guidelines, residual gastric content can persist in some patients, increasing the risk of aspiration pneumonitis. Multiple patient-specific factors may predict gastric content retention, but their predictive accuracy is limited. We hypothesized that ultrasound would more reliably identify residual gastric content compared to a comprehensive questionnaire and aimed to determine the most practical approach for risk assessment in elective surgical patients. Methods: We conducted a prospective, observational study in adult patients scheduled for elective surgery at a single center. All participants adhered to an 8 h fasting period. The primary outcome was the incidence of a “full stomach” on ultrasound. Secondary outcomes included the Perlas risk classification, comparisons of established volume estimation formulas, correlations with self-reported fasting duration, agreement between questionnaire-based predictions and ultrasound findings, and the time efficiency of each method. Multivariable logistic regression and Cohen’s kappa were used for analyses. Results: Data from 404 patients were analyzed. Despite prolonged fasting, 16.3% had a full stomach by ultrasound, suggesting incomplete gastric emptying. Early satiety and cholelithiasis significantly predicted a full stomach; prolonged fasting duration and female sex were protective. Questionnaire-based predictions demonstrated fair agreement with ultrasound (kappa = 0.327). The Michiko formula often yielded negative volumes, highlighting limitations in volume estimations. Ultrasound examination (3 min median) was faster than questionnaire completion (5 min). Conclusions: Ultrasound accurately detects residual gastric content, outperforming questionnaire-based assessments. Integrating it into routine preoperative evaluation may improve patient safety, although research is needed to refine volume estimation formulas and expand feasibility for patients with positioning limitations.
Evolution of the Quality of Care in Patients with Decompensated Heart Failure in a Venezuelan Hospital
Authors: Torres Yaneth , Benitez Daniel , Morillo Zenaida , Salazar Juan , Contreras-Velasquez Julio , Bermudez Valmore
Published: January 2025

Background/Objectives: Several parameters have been proposed for the objective measurement of the quality of care (QoC) and breaches of care in patients with heart failure (HF). Therefore, the objective of this study was to evaluate the measures of QoC in inpatients with decompensated HF in the cardiology department of a tertiary Venezuelan hospital. Methods: An observational, descriptive, ambispective study was conducted with adults of all genders diagnosed with decompensated HF between 2022 and 2024. Sociodemographic, clinical, and therapeutic variables were assessed, as well as psychobiologic habits, measures of QoC, readmissions, and in-hospital mortality within the first 6 months of care. Results: Among the 131 subjects evaluated, the average age was 63.6 ± 14.1 years, with 58% (n = 76) being male. Among the in-hospital measures of QoC, the most common was the programming for follow-up consultations (98.5%; n = 129), followed by the prescription of beta-blockers (90.1%; n = 118). An upwards trend was also observed in the later years regarding the frequency of left ventricle ejection fraction (LVEF) assessment (p < 0.001), and the use of iSGLT2 (p = 0.03). During follow-up, 36.6% of the patients died within 6 months, with those in NYHA class IV showing a higher probability of death (OR: 3.84; CI95%: 0.89–16.55; 0.04). Conclusions: The in-hospital measures for QoC in this population were similar to those in previous reports, with LVEF assessment and iSGLT2 prescription showing a particularly significant increase in recent years.
Evaluation of Conventional and Combined Doppler Parameters in Preeclampsia: Diagnostic and Prognostic Insights
Authors: Karabay Gulsan , Bayraktar Burak , Seyhanli Zeynep , Filiz Ahmet Arif , Tokgoz Cakir Betul , Aktemur Gizem , Tonyali Nazan Vanli , Agaoglu Recep Taha , Kocaoglu Gulcan , Karabay Umut , Yucel Kadriye Yakut
Published: January 2025

Background: The aim of this study was to examine the relationship between conventional and novel Doppler parameters, including cerebroplacental ratio (CPR), cerebral–placental–uterine ratio (CPUR), umbilical-to-cerebral ratio (UCR), and amniotic-to-umbilical-cerebral ratio (AUCR), with the diagnosis of preeclampsia (PE) and adverse neonatal outcomes in PE cases. Methods: This prospective case-control study was conducted at the Ankara Etlik City Hospital Perinatology Clinic between November 2023 and May 2024. The study population was divided into two groups: Group 1, consisting of 74 patients diagnosed with preeclampsia, and Group 2, consisting of 80 healthy control patients. Composite adverse perinatal outcomes (CANOs) include presence of at least one adverse outcome: 5th-minute APGAR score < 7, transient tachypnea of the newborn (TTN), respiratory distress syndrome (RDS), need for continuous positive airway pressure (CPAP), need for mechanical ventilation, neonatal intensive care unit (NICU) admission, neonatal hypoglycemia, need for phototherapy, intraventricular hemorrhage (IVH), and neonatal sepsis. Results: The CPR, CPUR, and AUCR were significantly lower in the PE group compared to the control group, while the UCR was notably higher in the PE group. Among the combined ratios, the CPUR exhibited the highest diagnostic performance for both PE diagnosis and the prediction of CANOs. Additionally, while the UCR, CPR, and AUCR were significant for PE diagnosis, only AUCR demonstrated a significant association with the prediction of CANOs. Conclusions: Combined Doppler parameters, especially CPUR and AUCR, offer valuable insights into diagnosing PE and predicting CANOs. CPUR demonstrated the highest diagnostic accuracy, underscoring its potential utility in clinical settings.
Enhancing Mechanical Properties of Polyamide 66 with Carbon-Based Nano-Fillers: A Review
Authors: Avbar Matija , Oliveira Gean Henrique Marcatto de , Amancio-Filho Sergio de Traglia
Published: January 2025

Carbon-based nanofillers have emerged as promising agents for enhancing the mechanical properties of polyamide 66 (PA66). This literature review emphasizes the increasing interest in nanocomposites due to their ability to significantly improve material properties, often surpassing traditional short fiber reinforced polymers, even at low nanofiller loadings. Across the studies reviewed, consistent enhancements in various quasi-static mechanical properties are observed upon the incorporation of nanofillers. Optimal carbon-based nanofiller loadings typically fall within the range of 0.25% to 1 wt%. Notably, significant improvements have been reported, with increases of up to 78% in Young’s modulus (E) and 138% in ultimate tensile strength (UTS). This comprehensive analysis highlights the potential of carbon-based nanofillers in enhancing the performance of polyamide 66, offering valuable insights for the design and development of advanced nanocomposite materials. Preliminary test results by the authors, where melt mixing was employed to produce PA66 carbon nanotube (CNT) nanocomposites with loadings of up to 1 wt%, show an increase in Young’s modulus whilst the ultimate tensile strength and strain at break (SaB) are reduced.
Numerical Study of Inclined Geometric Configurations of a Submerged Plate-Type Device as Breakwater and Wave Energy Converter in a Full-Scale Wave Channel
Authors: Motta Vitor Eduardo , Thum Gabrielle Ücker , Gonçalves Rafael Adriano Alves Camargo , Rocha Luiz Alberto Oliveira , dos Santos Elizaldo Domingues , Machado Bianca Neves , Isoldi Liércio André
Published: January 2025

The climate crisis represents one of the greatest contemporary global challenges, requiring actions to mitigate its impacts and sustainable solutions to meet the growing demands for clean energy and coastal protection. Therefore, the study of devices such as the submerged plate (SP), which simultaneously acts as a breakwater (BW) and wave energy converter (WEC), is especially relevant. In this context, the present numerical study compares the efficiency of an SP device under regular waves across different geometric configurations considering inclination angles. To achieve this, a horizontal SP was adopted as a reference. Its thickness and total material volume were kept constant while ten alternative geometries, each with a different inclination for the SP, were proposed and investigated. The computational domain was modeled as a full-scale regular wave channel with each SP positioned below the free surface. The volume of fluid (VOF) multiphase model was employed to represent the interaction between water and air. The finite volume method (FVM) was applied to solve the transport equations for volume fraction, momentum, and mass. The SP’s efficiency as a BW was evaluated by assessing the free surface elevation upstream and downstream of the SP, while its efficiency as a WEC was measured by evaluating the axial velocity below the SP. Results indicated that the efficiency of the SP can vary significantly depending on its inclination, with the optimal case at θ = 15° showing improvements of 11.95% and 16.59%, respectively, as BW and WEC.
A Comparative Analysis Between the ENVISAT and ICEYE SAR Systems for the Estimation of Sea Surface Current Velocity
Authors: Zamparelli Virginia , Mastro Pietro , Pepe Antonio , Verde Simona
Published: January 2025

In this work, we present the results of a comparative analysis between the first-generation Advanced Synthetic Aperture Radar (ASAR) sensor mounted on board the ENVISAT platform and the novel ICEYE micro-satellite synthetic aperture radar (SAR) sensor in measuring the radial velocity of ocean currents through the Doppler Centroid Anomaly (DCA) technique. First, the basic principles of DCA and the theoretical precision of the Doppler Centroid (DC) estimates are introduced. Subsequently, the role of the DC measurements in retrieving the sea surface current velocity is addressed. To achieve this goal, two sets of SAR data gathered by ASAR (C-band) and from the X-band ICEYE instruments, respectively, are exploited. The standard deviation of DCA measurements is derived and tested against what is expected by theory. The presented analysis results are beneficial to evaluate the pros and cons of the new-generation X-band to the first-generation ASAR/ENVISAT system, which has been extensively exploited for ocean currents monitoring applications. As an outcome, we find that with inherently selected methods for DC estimates, the performance offered by ICEYE is comparable to, or even better than (with specific parameters selection), the consolidated approaches based on the ASAR sensor. Nonetheless, new SAR constellations offer an undoubted advantage regarding improved spatial resolution and time repeatability.
Emission Estimation and Spatiotemporal Distribution of Passenger Ships Using Multi-Source Data: A Case from Zhoushan (China)
Authors: Xu Xubiao , Liu Xingyu , Feng Lin , Yap Wei Yim , Feng Hongxiang
Published: January 2025

Quantifying and estimating shipping emissions is a critical component of global emission reduction research and has become a growing area of interest in recent years. However, emissions from short-distance passenger ships operating on inter-island routes and their environmental impacts have received limited attention. This contribution investigated the temporal and spatial distribution characteristics of pollutants emitted by short-distance passenger ships at Zhoushan (China) using Automatic Identification System (AIS) data and the bottom–up emission model integrated with multi-source meteorological data. A year-long emission inventory was investigated. The results indicated that high-speed passenger ships contributed to the largest share of the emissions. The emissions were predominantly concentrated during daytime hours, with the routes between Zhoushan Island and Daishan, Daishan and Shengsi, and Zhoushan Island and Liuheng Island accounting for most of the emissions. Furthermore, intra-port waterways were identified as the primary emission areas for short-distance passenger ships. This study provides essential data support and references for the relevant authorities to understand the emission patterns of short-distance passenger ships, thereby facilitating the formulation of targeted emission reduction strategies for the maritime passenger transport sector.
Identity and Distribution of Triglops metopias (Teleostei, Cottidae) in the Northwestern Pacific
Authors: Prokofiev Artem M. , Mukhametov Ilyas N. , Emelianova Olga R. , Orlova Svetlana Yu. , Orlov Alexei M.
Published: January 2025

The Alaskan (highbrow) sculpin, Triglops metopias, is a rare and poorly known species with a restricted distribution in the North Pacific. This species has been previously recorded only from off the Aleutian Islands and the Gulf of Alaska, while previous records from the western North Pacific have been controversial. The presence of T. metopias in the northwestern Pacific off the Kuril Islands is confirmed in the current study. Forty-one specimens were included in morphological and molecular analyses, including principal component analysis and DNA barcoding. The detailed morphological description of the Kuril Islands specimens is given. Molecular analysis inferred from the mitochondrial cytochrome b sequences showed no separation of this species from T. pingelii, although they can be distinguished by external morphology, including the use of the multivariate statistical approach. The geographical distribution of T. metopias in the North Pacific is discussed. This species is considered to be a recently diverged species with a disjunct distribution from the Kuril and the Aleutian Islands eastwards to the Gulf of Alaska. Despite its morphological similarity to T. pingelii, both species can be distinguished by a combination of meristic and morphometric characters, in particular, the wider interorbital space (10.4–22.4, mean 14.8 vs. 6.9–11.4, mean 9.2), shorter pectoral fins (18.7–24.9, mean 21.0 vs. 21.7–27.4, mean 24.1), and the on average more numerous oblique dermal folds (92 vs. 54).
Semi-Quantitative Indicators of Safety Culture Evolution Through Graduate Researcher Led Initiatives
Authors: Adrahtas Demetra Z. , Bresnahan Brady L. , Lynch Pauline G. , Ramírez-Lopez Sofía , Andersson Brian
Published: January 2025

Since 2012, the Joint Safety Team (JST) has led initiatives aimed at increasing safety awareness and improving safety culture in research laboratory environments at the University of Minnesota. Specifically, its Analysis and Compliance committee has implemented biannual lab safety walkthroughs and safety surveys to monitor safety culture, sentiments, and compliance. Despite several lab safety teams (LSTs) using similar initiatives, the logistics and effectiveness of these initiatives have yet to be reported. Hence, JST has analyzed the decade of overall lab safety walkthrough scores and scores of individual safety items in the context of the evolution of our rubrics and external factors. Similarly, the changes to the safety survey content have been analyzed to demonstrate the dynamic approach of gauging sentiments towards arising safety issues. Generally, the results suggest that these initiatives improved laboratory safety. Furthermore, safety compliance was observed to vary by semester, with fewer safety issues in the spring semester compared to the fall semester, and to be affected by the COVID-19 pandemic. These observations support the effectiveness of these student-led initiatives, despite the initiatives being designed for internal use. Additionally, the initiative logistics are described to inform LSTs of strategies for creating, sustaining, and improving their own initiatives.
A Study on the Spatiotemporal Heterogeneity and Driving Forces of Ecological Resilience in the Economic Belt on the Northern Slope of the Tianshan Mountains
Authors: Li Keqi , Yan Qingwu , Wu Zihao , Li Guie , Yi Minghao , Ma Xiaosong
Published: January 2025

The assessment of ecological resilience in arid regions is crucial for understanding and mitigating the impacts of climate change and human activities, ensuring the sustainable management of these vulnerable ecosystems. Taking the Economic Belt on the Northern Slope of the Tianshan Mountains (EBNSTM) as the research area, a multi-dimensional evaluation model coupling vulnerability, health, and connectivity was used to explore the spatiotemporal variation and driving forces of ecological resilience. Firstly, a sub-item evaluation of ecological resilience was conducted from three aspects, including ecological vulnerability evaluation based on the CRITIC and AHP models, ecological health evaluation based on the InVEST model, and landscape connectivity evaluation based on the MSPA method. Then, the sequence polygon method was utilized to conduct a comprehensive multi-dimensional assessment of ecological resilience based on the aforementioned three evaluation results. Finally, the geographical detector model was utilized to identify the driving factors behind the spatial heterogeneity of ecological resilience. The results show the following: (1) From 2000 to 2020, the overall ecological resilience showed an upward trend and significant spatial heterogeneity. The overall distribution pattern exhibited a spatial feature of south higher, north lower, where the southern region displayed a clear high-high clustering characteristic, exerting a positive and radiating influence on surrounding areas. (2) The main driving factors of the spatial heterogeneity are DEM, precipitation, NPP, GDP, and PM2.5. And among different factors, the dual-factor enhancement effect is greater than the nonlinear enhancement of a single factor. (3) Human activities are important influencing factor, and the impact of urban expansion and economic growth on ecological resilience is becoming increasingly significant. Therefore, in the process of economic development, full consideration should be given to the self-repairing and adaptive capabilities of the ecosystem.
Responses of Typical Riparian Vegetation to Annual Variation of River Flow in a Semi-Arid Climate Region: Case Study of China’s Xiliao River
Authors: Yan Xiangzhao , Yang Wei , Pu Zaohong , Zhang Qilong , Chen Yutong , Chen Jiaqi , Xiang Weiqi , Chen Hongyu , Cheng Yuyang , Zhao Yanwei
Published: January 2025

In semi-arid basins, riparian vegetation is an important part of the river ecosystem. However, with the decrease in river runoff caused by human activities and the continuous changes in climate, riparian vegetation has gradually degraded. To identify the main influencing factors of riparian vegetation changes, we extracted the river flow indicators, climate indicators, and riparian vegetation indicators of a Xiliao River typical section from 1985 to 2020 in spring and summer, and established a random forest model to screen the key driving factors of riparian vegetation. Then, we simulated the response characteristics of riparian vegetation to the key driving factors in spring and summer based on nonlinear equations. The results showed that the contribution of river flow factors to riparian vegetation was higher than that of climate factors. In spring, the key driving factors of riparian vegetation were the average flow in May and the average flow from March to May; in summer, the key driving factors were the average flow in May, the maximum 90-day average flow, and the average flow from March to August. Among them, the average flow in May contributed more than 50% to the indicators of riparian vegetation in both spring and summer. The final conclusion is that in the optimal growth range of plants, increasing the base flow and pulse flow of rivers will promote seed germination and plant growth, but when the river flow exceeds this threshold, vegetation growth will stagnate. The research results improve the existing knowledge of the influencing factors of riparian vegetation in semi-arid basins, and provide a reference for improving the natural growth of riparian vegetation and guiding the ecological protection and restoration of rivers in semi-arid areas.
Spatial–Temporal Evolution and Influencing Mechanism of Coupling Coordination Level of Social–Ecological Systems in China’s Resource-Based Cities Under the Carbon Neutrality Goal
Authors: Zhang Yunhui , Wang Zhong , Peng Yanran , Wang Wei , Tian Chengxi
Published: January 2025

Carbon emissions have a profound impact on the transformation goals and development paths of cities. In the context of carbon neutrality, it is of great significance to explore the coupling coordination level of the social–ecological systems in resource-based cities for realizing regional low-carbon and sustainable development. In this study, the entropy weighting method, coupling coordination degree model and geographical detector were used to measure the comprehensive development level and coupling coordination level of the social–ecological system in 116 resource-based cities in China from 2010 to 2020 and their spatial–temporal characteristics and influencing mechanism were analyzed. The results show the following: (1) The comprehensive development level of the social system in China’s resource-based cities has a significant upward trend, while the comprehensive development level of the ecological system has a gentle upward trend, and the coupling and coordination level of the social–ecological system has a fluctuating upward trend. (2) There is obvious spatial differentiation between the comprehensive development level and the coupling coordination level of the social–ecological systems in resource-based cities in China, and the relative difference is gradually increasing. (3) The digital economy index, urbanization level, science and education investment, and population density are important factors affecting the coupling coordination level, and the interaction between digital economy index, urbanization level, and population density has a strong explanatory power in the differentiation of the coupling coordination level. Based on the above conclusions, effective policy recommendations are put forward: formulate more refined and differentiated development paths, co-ordinate the spatial layout to give full play to the role of urban agglomeration, vigorously develop the digital economy, increase investment in science and education, rely on scientific and technological innovation to create development advantages, reasonably guide the population layout and take a new urbanization development route.
Spleno-Mesenteric Venous Blood Flow Dynamics in Adult Patients with Chronic Portal Vein Thrombosis Analyzed by Sequential CT-Spleno- and Mesenterico-Portography
Authors: Schlitt Alexandra , Goetz Andrea , Stroszczynski Christian , Zeman Florian , Hackl Christina , Schlitt Hans J. , Jung Ernst-Michael , Uller Wibke , Hammer Simone
Published: January 2025

Background: Portal vein thrombosis (PVT) leads to portal hypertension (PH) with its sequelae. Computed tomography spleno-mesenterico-portography (CT-SMPG) combines sequential CT spleno-portography and CT mesenterico-portography. CT-SMPG comprehensively illustrates the venous hemodynamic changes due to PH. Objective: To assess the effects of PV confluence thrombosis (PVCT) and liver cirrhosis on venous blood flow characteristics of patients with PVT. Method: CT-SMPG was performed in 21 patients with chronic PVT. CT-SMPG was compared to standard contrast-enhanced CT (CECT) and gastroscopy concerning the patency of splanchnic veins, varices and venous congestion. Results: PVCT had a significant effect on perfusion patterns: in patients without PVCT, esophageal varices (EV) and gastric varices were supplied by either the splenic vein (SV), the superior mesenteric vein (SMV), or both. In patients with PVCT, EV and gastric varices were mostly supplied by the SV (p = 0.021, p = 0.016). In patients without PVCT, small bowel varices were fed by both systems or the SMV, while in patients with PVCT they were fed by the SMV (p = 0.031). No statistically significant changes were detected regarding gastropathy, colorectal varices and small bowel congestion. Liver cirrhosis had no statistically relevant effect on hemodynamics. Conclusions: In CT-SMPG, patients with PVCT showed different venous hemodynamics to patients without PVCT, and this can serve as a basis for selecting therapy options.
Functional Connectivity and MRI Radiomics Biomarkers of Cognitive and Brain Reserve in Post-Stroke Cognitive Impairment Prediction—A Study Protocol
Authors: Dragoș Hanna Maria , Stan Adina , Popa Livia Livinț , Pintican Roxana , Feier Diana , Drăghici Nicu Cătălin , Jianu Dragoș-Cătălin , Chira Diana , Strilciuc Ștefan , Mureșanu Dafin F.
Published: January 2025

Acute ischemic stroke (AIS) is frequently associated with long-term post-stroke cognitive impairment (PSCI) and dementia. While the mechanisms behind PSCI are not fully understood, the brain and cognitive reserve concepts are topics of ongoing research exploring the ability of individuals to maintain intact cognitive performance despite ischemic injuries. Brain reserve refers to the brain’s structural capacity to compensate for damage, with markers like hippocampal atrophy and white matter lesions indicating reduced reserve. Cognitive reserve involves the brain’s ability to optimize performance and use alternative networks to maintain function. Advanced methods of MRI and EEG processing may better assess brain reserve and cognitive reserve, with emerging predictive models integrating these measures to improve PSCI prediction. This article provides the design of a hospital-based study investigating the predictive role of functional connectivity and MRI radiomics in assessing PSCI occurrence one year after AIS. One hundred forty-four patients will be enrolled following strict inclusion/exclusion criteria. The patients will undergo comprehensive assessments, including neuropsychological testing, brain MRI, and quantitative EEG (QEEG), across four visits over a year. The primary outcome will be PSCI occurrence, and it will be assessed at six and twelve months after AIS. Secondary outcomes will include PSCI severity, recurrent AIS, and mortality. Statistical analyses will be performed to identify predictive factors using Cox proportional hazards models, and predictive models based on QEEG, MRI radiomics, and clinical data will be built. Early detection of AIS patients prone to developing PSCI might outline more effective therapeutic approaches, reducing the social and economic burden of ischemic stroke.
Resilience and Adaptability in Paracetamol Supply Chains: A Systems Perspective on COVID-19 Challenges and Responses in Ethiopia
Authors: Melaku Tsegaye , Mekonnen Zeleke , Tucho Gudina Terefe , Viana Joe , Årdal Christine , Jahre Marianne
Published: January 2025

Background: The COVID-19 pandemic exposed vulnerabilities in global supply chains, including those for essential medicines like paracetamol. This study aimed to assess the resilience and adaptability of Ethiopia’s paracetamol supply chain during the pandemic. Methods: A mixed-methods approach was employed, combining semi-structured interviews with key stakeholders and analysis of secondary data on paracetamol availability and supply chain disruptions. The study employed systems thinking and supply chain resilience frameworks, utilizing causal loop diagrams to visualize system dynamics. Results: Eighteen stakeholders, representing seven pharmaceutical manufacturers, five import companies, and five wholesalers, participated in the study. These participants had between three and fourteen years of experience in their respective roles. The study revealed complex interactions within the paracetamol supply chain, highlighting both challenges and adaptive responses. While 500 mg paracetamol tablets were readily available, shortages of other formulations were observed due to a range of factors, including limited product diversification, political instability, inflation, and reduced production efficiency. Conclusions: The resilience and adaptability of stakeholders, particularly manufacturers and importers, were crucial in maintaining the supply of 500 mg paracetamol tablets. Key strategies included regional sourcing, increased production, and improved partnerships. Understanding the interconnectedness of factors within the supply chain is essential for developing effective strategies to enhance its resilience and ensure sustained access to paracetamol in the future.
Research on Constitutive Modeling of DH460 Continuous Casting Steel with the Solidification End Reduction Process
Authors: Liang Bochun , Han Chunxi , Zhao Tan , Ji Cheng , Zhu Miaoyong
Published: January 2025

The constitutive model was commonly used to describe the flow stress of materials under specific strain, strain rate, and temperature conditions. In order to study the thermal–mechanical behavior of DH460 continuous casting steel during the solidification end heavy reduction (HR) process accurately. The high-temperature compression experiment was carried out, and phenomenological constitutive models were established based on the experimental results. A new strain-strengthening factor (D(ε)) was proposed in order to improve the prediction accuracy of the current constitutive models. Then, the further-modified models were established. It was found that the new strain-strengthening factor significantly reduced the error of models. The average relative error (AARE) of the further-modified Johnson–Cook model and the further-modified Zerilli–Armstrong model were 6.27% and 5.54%, respectively. The results showed that the further-modified models were more suitable for describing the constitutive behavior of DH460 continuous casting steel during the solidification end reduction.
Structural, Electronic, and Magnetic Properties of Neutral Borometallic Molecular Wheel Clusters
Authors: Perveen Saira , Gonzalez Szwacki Nevill
Published: January 2025

Atomic clusters exhibit properties that fall between those found for individual atoms and bulk solids. Small boron clusters exhibit planar and quasiplanar structures, which are novel materials envisioned to serve as a platform for designing nanodevices and materials with unique physical and chemical properties. Through past research advancements, experimentalists demonstrated the successful incorporation of transition metals within planar boron rings. In our study, we used first-principles calculations to examine the structure and properties of neutral boron clusters doped with transition metals, denoted as TMBn and TMB2n, where TM = Ti, Cr, Mn, Fe, Co, Nb, or Mo and n=8–10. Our calculations show that the TMB2n structures, which involve sandwiching metal atoms between two rings (called the drum configuration), and clusters with the single ring configuration, TMBn, are stable. These clusters typically have relatively large HOMO-LUMO energy gaps, suggesting high kinetic stability and low chemical reactivity. Moreover, the clusters display interesting magnetic properties, determined not only by the metal atoms but also by the induced magnetism of the boron rings. These structures have potential applications in spintronics and sensing. This work also provides a basis for studying magnetism in the one-dimensional limit.
Effect of Clamped Member Material and Thickness on Bolt Self-Loosening Under Transverse Loads
Authors: Rousseau Rashique Iftekhar , Bouzid Abdel-Hakim
Published: January 2025

Bolted joints, prevalent in industrial applications for component fastening, are susceptible to self-loosening—a critical issue resulting in a gradual reduction in clamping force. Gaining insight into the underlying mechanisms of self-loosening is crucial. While prior research has largely focused on evaluating component stiffness, limited attention has been given to its impact on the self-loosening behavior of bolted joints under transverse cyclic loading. This study investigates how component stiffness influences self-loosening in bolted joints by varying the material and thickness of clamped members. An experimental setup replicating real-world conditions is devised to simulate loosening caused by cyclic lateral displacement. Tests are conducted using steel and high-density polyethylene (HDPE) clamped members of different grip lengths to explore the relationship between stiffness and self-loosening. Key parameters measured include bolt axial load, transverse force on clamped members, relative displacement, and rotation between the bolt and nut. The findings provide valuable insights into the effects of stiffness across various clamped member materials and grip length combinations, which can enhance the understanding of conditions that promote loosening resistance. Moreover, by highlighting stage-II or rotational loosening, with each test resulting in complete preload loss, the study provides a comparative analysis of the influencing factors. This enables the identification of distinct loosening patterns and supports the development of improved bolted joint designs to reduce loosening.
Complex Inhibitor Protection of Some Steels in Hydrochloric Acid Solutions by 1,2,4-Triazole Derivatives
Authors: Avdeev Yaroslav G. , Nenasheva Tatyana A. , Luchkin Andrey Y. , Marshakov Andrey I. , Kuznetsov Yurii I.
Published: January 2025

The behavior of low-carbon steels (LCSs), a high-strength steel and a nickel–chromium alloy in HCl solutions in the presence of N-containing organic substances has been studied. N-containing organic substances that comprise 1,2,4-triazole in their structure (substance I and substance II) provide comprehensive protection of various steel grades from corrosion and hydrogen absorption by the metal bulk in HCl solutions under both isobaric and isochoric conditions. All the compounds studied reduce, to varying degrees, the concentration of hydrogen adsorbed and absorbed by steel in HCl solutions. The most promising way to expand the scope of application is to use substance I in HCl solutions for protecting steels from high-temperature corrosion as a mixture with hexamethylenetetramine (HMT). In 2 M HCl (100 °C) under isochoric conditions, a mixture of compound I and HMT exhibited an excellent result: the degree of protection of LCS against corrosion was 99.5%. Substance I and its mixture with HMT protect steels not only in pure HCl solutions, but also in environments contaminated with hydrogen sulfide, which is especially important for the acid stimulation of wells in oil production.
Treatment and Valorization of Waste Wind Turbines: Component Identification and Analysis
Authors: Zhao Xiaohan , Pakuła Daria , Frydrych Miłosz , Konieczna Roksana , Sztorch Bogna , Kozera Rafał , Liu Hongzhi , Zhou Hui , Przekop Robert E.
Published: January 2025

Recycling end-of-life wind turbines poses a significant challenge due to the increasing number of turbines going out of use. After many years of operation, turbines lose their functional properties, generating a substantial amount of composite waste that requires efficient and environmentally friendly processing methods. Wind turbine blades, in particular, are a problematic component in the recycling process due to their complex material composition. They are primarily made of composites containing glass and carbon fibers embedded in polymer matrices such as epoxies and polyester resins. This study presents an innovative approach to analyzing and valorizing these composite wastes. The research methodology incorporates integrated processing and analysis techniques, including mechanical waste treatment using a novel compression milling process, instead of traditional knife mills, which reduces wear on the milling tools. Based on the differences in the structure and colors of the materials, 15 different kinds of samples named WT1-WT15 were distinguished from crushed wind turbines, enabling a detailed analysis of their physicochemical properties and the identification of the constituent components. Fourier transform infrared spectroscopy (FTIR) identified key functional groups, confirming the presence of thermoplastic polymers (PET, PE, and PP), epoxy and polyester resins, wood, and fillers such as glass fibers. Thermogravimetric analysis (TGA) provided insights into thermal stability, degradation behavior, and the heterogeneity of the samples, indicating a mix of organic and inorganic constituents. Differential scanning calorimetry (DSC) further characterized phase transitions in polymers, revealing variations in thermal properties among samples. The fractionation process was carried out using both wet and dry methods, allowing for a more effective separation of components. Based on the wet separation process, three fractions—GF1, GF2, and GF3—along with other components were obtained. For instance, in the case of the GF1 < 40 µm fraction, thermogravimetric analysis (TGA) revealed that the residual mass is as high as 89.7%, indicating a predominance of glass fibers. This result highlights the effectiveness of the proposed methods in facilitating the efficient recovery of high-value materials.
Design and Experimental Characterization of Developed Human Knee Joint Exoskeleton Prototypes
Authors: Olinski Michał
Published: January 2025

This paper focuses on the experimental testing and characterisation of two designed and constructed prototypes of a human knee joint mechanism. The aim of the mechanical systems, presented as kinematic diagrams and 3D CAD drawings, is to reproduce the knee joint’s complex movement, in particular the flexion/extension in the sagittal plane, within a given range and constraints, while taking into account the trajectory of the joint’s instantaneous centre of rotation. The first prototype can simulate different movements by modifying its dimensions in real time using a linearly adjustable crossed four-bar mechanism. The second prototype has interchangeable cooperating components, with cam profiles that can be adapted to specific requirements. Both devices are built from 3D-printed parts and their characteristics are determined experimentally. Although many types of tests have been carried out, this research mainly aims to conduct experiments with volunteers. To this end, the IMU sensors measure the mechanisms’ movements, but the main source of the data is video analysis of the colour markers. For the purposes of postprocessing, the results in the form of numerical values and figures were computed by Matlab 2019b. To illustrate the prototypes’ capabilities, the results are shown as motion trajectories of selected tibia/femur points and the calculated knee joint’s flexion/extension angle.
Uniqueness of Positive Solutions to Non-Local Problems of Brézis–Oswald Type Involving Hardy Potentials
Authors: Kim Yun-Ho
Published: January 2025

The aim of this paper is to demonstrate the existence of a unique positive solution to non-local fractional p-Laplacian equations of the Brézis–Oswald type involving Hardy potentials. The main feature of this paper is solving the difficulty that arises in the presence of a singular coefficient and in the lack of the semicontinuity property of an energy functional associated with the relevant problem. The main tool for overcoming this difficulty is the concentration–compactness principle in fractional Sobolev spaces. Also, the uniqueness result of the Brézis–Oswald type is obtained by exploiting the discrete Picone inequality.
An Upper Bound for Locating Strings with High Probability Within Consecutive Bits of Pi
Authors: Silva-García Víctor Manuel , Cardona-López Manuel Alejandro , Flores-Carapia Rolando
Published: January 2025

Numerous studies on the number pi (π) explore its properties, including normality and applicability. This research, grounded in two hypotheses, proposes and proves a theorem that employs a Bernoulli experiment to demonstrate the high probability of encountering any finite bit string within a sequence of consecutive bits in the decimal part of π. This aligns with findings related to its normality. To support the hypotheses, we present experimental evidence about the equiprobable and independent properties of bits of π, analyzing their distribution, and measuring correlations between bit strings. Additionally, from a cryptographic perspective, we evaluate the chaotic properties of two images generated using bits of π. These properties are evaluated similarly to those of encrypted images, using measures of correlation and entropy, along with two hypothesis tests to confirm the uniform distribution of bits and the absence of periodic patterns. Unlike previous works that solely examine the presence of sequences, this study provides, as a corollary, a formula to calculate an upper bound N. This bound represents the length of the sequence from π required to ensure the location of any n-bit string at least once, with an adjustable probability p that can be set arbitrarily close to one. To validate the formula, we identify sequences of up to n= 40 consecutive zeros and ones within the first N bits of π. This work has potential applications in Cryptography that use the number π for random sequence generation, offering insights into the number of bits of π required to ensure good randomness properties.
A Robust Hermitian and Skew-Hermitian Based Multiplicative Splitting Iterative Method for the Continuous Sylvester Equation
Authors: Khorsand Zak Mohammad , Abbaszadeh Shahri Abbas
Published: January 2025

For solving the continuous Sylvester equation, a class of Hermitian and skew-Hermitian based multiplicative splitting iteration methods is presented. We consider two symmetric positive definite splittings for each coefficient matrix of the continuous Sylvester equations, and it can be equivalently written as two multiplicative splitting matrix equations. When both coefficient matrices in the continuous Sylvester equation are (non-symmetric) positive semi-definite, and at least one of them is positive definite, we can choose Hermitian and skew-Hermitian (HS) splittings of matrices A and B in the first equation, and the splitting of the Jacobi iterations for matrices A and B in the second equation in the multiplicative splitting iteration method. Convergence conditions of this method are studied in depth, and numerical experiments show the efficiency of this method. Moreover, by numerical computation, we show that multiplicative splitting can be used as a splitting preconditioner and induce accurate, robust and effective preconditioned Krylov subspace iteration methods for solving the continuous Sylvester equation.
The Gyrokinetic Limit for the Two-Dimensional Vlasov–Yukawa System with a Point Charge
Authors: Hu Xianghong , Zhang Xianwen
Published: January 2025

In this article, we study the asymptotic behavior of the two-dimensional Vlasov–Yukawa system with a point charge under a large external magnetic field. When the intensity of the magnetic field tends to infinity, we show that the kinetic system converges to the measure-valued Euler equation with a defect measure, which extends the results of Miot to the case of the Vlasov–Yukawa system. And compared with the Miot’s work, an important improvement is that our results do not require compact support conditions for spatial variables or uniform bound conditions for second-order spatial moments. In addition, the extra small condition for initial data is also not required.
Two-Party Quantum Private Comparison Protocol for Direct Secret Comparison
Authors: Hou Min , Wu Yue
Published: January 2025

In this paper, we leverage the properties of the swap test to evaluate the similarity of two qubits and propose a two-party quantum private comparison (QPC) protocol involving a semi-trusted third party (TP). The TP facilitates the comparison between participants without accessing their private information, other than the final comparison results. Our protocol encodes participants’ secret integers directly into the amplitudes of single-photon states and introduces a novel method for secret-to-secret comparison rather than the traditional bit-to-bit comparison, resulting in improved scalability. To ensure security, the encoded single-photon states are concealed using rotation operations. The comparison results are derived through the implementation of the swap test. A simulation on the IBM Quantum Platform demonstrates the protocol’s feasibility, and a security analysis confirms its robustness against potential eavesdropping and participant attacks. Compared with existing QPC protocols that employ bit-to-bit comparison methods, our approach offers improved practicality and scalability. Specifically, it integrates single-photon states, rotation operations, and the swap test as key components for direct secret comparison, facilitating easier implementation with quantum technology.
Deep-Sea-Derived Isobisvertinol Targets TLR4 to Exhibit Neuroprotective Activity via Anti-Inflammatory and Ferroptosis-Inhibitory Effects
Authors: Xu Zi-Han , Xie Ming-Min , Xie Chun-Lan , Yang Xian-Wen , Wang Jun-Song
Published: January 2025

Neuroinflammation and neuronal cell death are leading causes of death in the elderly and underlie various neurodegenerative diseases. These diseases involve complex pathophysiological mechanisms, including inflammatory responses, oxidative stress, and ferroptosis. Compounds derived from deep-sea fungi exhibit low toxicity and potent neuroprotective effects, offering a promising source for drug development. In this study, we isolated 44 natural products from deep-sea-derived fungi and identified isobisvertinol (17) as a compound with anti-inflammatory and ferroptosis-inhibiting effects. Using LPS-induced microglial inflammation and RSL3-induced neuronal ferroptosis models, we found that 17 targets TLR4 to provide neuroprotection. Molecular docking studies revealed that 17 inhibits TLR4 activation by occupying the hydrophobic pocket at the TLR4-MD2 binding site. Additionally, 17 suppresses TLR4, reducing p38 MAPK phosphorylation, and inhibits ferroptosis by decreasing lipid peroxidation and modulating mitochondrial membrane potential. Metabolomic analysis showed that 17 rescues alterations in multiple metabolic pathways induced by RSL3 and increases levels of antioxidant metabolites, including glutamine, glutamate, and glutathione. In summary, our results indicate that isobisvertinol (17) targets TLR4 in neural cells to reduce inflammation and inhibit p38 MAPK phosphorylation, while regulating metabolic pathways, mainly GSH synthesis, to provide antioxidant effects and prevent ferroptosis in neurons.