bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Resident Behavioral Activities Based on Social Media Data: A Case Study of Four Typical Communities in Beijing
Authors: Ou Zhiyuan , Wang Bingqing , Meng Bin , Shi Changsheng , Zhan Dongsheng
Published: July 2024

With the support of big data mining techniques, utilizing social media data containing location information and rich semantic text information can construct large-scale daily activity OD flows for urban populations, providing new data resources and research perspectives for studying urban spatiotemporal structures. This paper employs the ST-DBSCAN algorithm to identify the residential locations of Weibo users in four communities and then uses the BERT model for activity-type classification of Weibo texts. Combined with the TF-IDF method, the results are analyzed from three aspects: temporal features, spatial features, and semantic features. The research findings indicate: ① Spatially, residents’ daily activities are mainly centered around their residential locations, but there are significant differences in the radius and direction of activity among residents of different communities; ② In the temporal dimension, the activity intensities of residents from different communities exhibit uniformity during different time periods on weekdays and weekends; ③ Based on semantic analysis, the differences in activities and venue choices among residents of different communities are deeply influenced by the comprehensive characteristics of the communities. This study explores methods for OD information mining based on social media data, which is of great significance for expanding the mining methods of residents’ spatiotemporal behavior characteristics and enriching research on the configuration of public service facilities based on community residents’ activity spaces and facility demands.
Comparative Toxicological Analyses of Traditional Matrices and Blow Fly Larvae in Four Cases of Highly Decomposed Human Cadavers
Authors: Peruch Michela , Buffon Maria , Jakovski Zlatko , Spiliopoulou Chara , Addobbati Riccardo , Franzin Martina , Magni Paola A. , D’Errico Stefano
Published: July 2024

In forensic investigation, determining the time and cause of death becomes challenging, especially in cases where the remains are found in advanced decomposition, rendering traditional toxicological samples unavailable or unreliable. Entomotoxicology, an emerging methodology within forensic science, leverages insect specimens collected from cadavers as alternative toxicological samples. Several laboratory and field research studies have highlighted the efficacy in detecting various drugs, toxins, and elements absorbed by insects feeding on cadaveric tissues, even at low concentrations. However, correlation studies between drug concentrations in conventional matrices and insects remain controversial due to unknown factors influencing drug metabolism and larval feeding activity. This paper presents four real cases in which human cadavers were discovered in advanced stages of decomposition, and toxicological analyses were performed on both insect samples and available matrices. The results presented complement the scant literature currently available on the application of entomotoxicology in real cases, providing insights into the correlation between larvae and human specimen results. Furthermore, guidelines to collect and preserve entomological evidence at the crime scene and during the autopsy for use in entomotoxicological analyses are provided. This advancement holds promise in aiding forensic investigations, particularly in cases where traditional methods cannot be applied or require supporting data for further validation.
A Female-Biased Chemosensory Protein PxutCSP19 in the Antennae of Papilio xuthus Tuned to Host Volatiles and Insecticides
Authors: Yin Ningna , Shen Dan , Liang Yinlan , Wang Pengfei , Li Yonghe , Liu Naiyong
Published: July 2024

Chemosensory protein (CSP) genes significantly enriched in the female antennae are potential molecular candidates for mediating female oviposition behaviors. In this study, we presented the interaction mechanisms of a female-antenna-biased PxutCSP19 in Papilio xuthus to 47 host volatiles, four biopesticides and 24 synthetic insecticides. Using a bioinformatics-based homology search, 22 genes orthologous to PxutCSP19 were identified from 22 other Papilio butterflies with high sequence identities to each other (73.20~98.72%). Multiple alignment analyses revealed a particularly extended N-terminus of Papilio CSP19s (an average of 154 residues) compared to insects’ typical CSPs (approximately 120 residues). The expression profiles indicated that PxutCSP19 was significantly enriched in the female antennae, with a 31.81-fold difference relative to the male antennae. In ligand-binding assays, PxutCSP19 could strongly bind six host odorants with high affinities, ranging from dissociation constant (Ki) values of 20.44 ± 0.64 μM to 22.71 ± 0.73 μM. Notably, this protein was tuned to a monoterpenoid alcohol, linalool, which generally existed in the Rutaceae plants and elicited electrophysiological and behavioral activities of the swallowtail butterfly. On the other hand, PxutCSP19 was also capable of binding eight insecticides with stronger binding abilities (Ki < 12 μM) compared to host odorants. When an extended N-terminal region of PxutCSP19 was truncated into two different proteins, they did not significantly affect the binding of PxutCSP19 to ligands with high affinities, suggesting that this extended N-terminal sequences were not involved in the specificity of ligand recognition. Altogether, our study sheds light on the putative roles of PxutCSP19 enriched in the female antennae of P. xuthus in the perception of host volatiles and the sequestering of insecticides, and it complements the knowledge of butterfly CSPs in olfaction and insecticide resistance.
The Modified Risk of Paradoxical Embolism Score Is Associated with Patent Foramen Ovale in Patients with Ischemic Stroke: A Nationwide US Analysis
Authors: Kwok Chun Shing , Alisiddiq Zaheer , Will Maximilian , Schwarz Konstantin , Khoo Chee , Large Adrian , Butler Robert , Lip Gregory Y. H. , Qureshi Adnan I. , Borovac Josip Andelo
Published: July 2024

Background: The Risk of Paradoxical Embolism (RoPE) score was developed to identify stroke-related patent foramen ovale (PFO) in patients with cryptogenic stroke. Methods: We conducted a retrospective analysis of the 2016 to 2020 National Inpatient Sample to determine the performance of the modified RoPE score in identifying the presence of a PFO in patients with acute ischemic stroke (AIS). Results: A total of 3,338,805 hospital admissions for AIS were analysed and 3.0% had PFO. Patients with PFO were younger compared to those without a PFO (median 63 years vs. 71 years, p < 0.001) and fewer were female (46.1% vs. 49.7%, p < 0.001). The patients with PFO had greater mean modified RoPE scores (4.0 vs. 3.3, p < 0.001). The area under the curve for the RoPE score in predicting PFOs was 0.625 (95%CI 0.620–0.629). The best diagnostic power of the RoPE score was achieved with a cut-off point of ≥4 where the sensitivity was 55% and the specificity was 64.2%. A cut-off point of ≥5 increased the specificity (83.1%) at the expense of sensitivity (35.8%). The strongest predictor of PFOs was deep vein thrombosis (OR 3.97, 95%CI 3.76–4.20). Conclusions: The modified RoPE score had modest predictive value in identifying patients with PFO among patients admitted with AIS.
Impact of the COVID-19 Pandemic on the Surgical Management of Head and Neck Non-Melanoma Skin Cancers in a Maxillofacial Center of Cluj-Napoca
Authors: Roman Rareș Călin , Faur Cosmin Ioan , Gordan Edina , Văleanu Mădălina , Moldovan Mădălina Anca
Published: July 2024

Background: The COVID-19 era has been a bleak period for both cancer and non-cancer patients, with delayed non-emergency treatments, such as for non-melanoma skin cancer (NMSC). This study aimed to evaluate how the treatment of NMSC patients was influenced by the management of the COVID-19 pandemic in an Eastern European Maxillofacial Surgery center. Materials and Methods: A total of 176 patients with a histopathological diagnosis of head and neck NMSC who were surgically treated in Cluj-Napoca Emergency County Hospital between 2016 and 2022 were included in this study, and divided into two samples, pre-pandemic (2016–2019) and COVID-19 (2020–2022) periods. Results: The pandemic presented with a decrease of 46.15% in patients’ hospitalization, with wealthy and educated patients being prevalent. Even if the waiting time for surgery was increased, the stage of cancer and preference method for reconstruction did not differ. Despite the lower addressability of NMSC patients during the pandemic, there were no changes in surgical treatment. Conclusions: During COVID-19, the number of patients was reduced, with a longer waiting time for surgery, but without any changes in tumor stage and treatment preferences. However, the benefit of removing a cancer tumor is higher compared to the risk of developing COVID-19 infection during hospitalization
The Era of DAAs: Assessing the Patients’ Characteristics, Clinical Impact, and Emergence of Comorbidities in HIV/HCV-Coinfected versus HIV-Infected Individuals
Authors: Álvarez-Álvarez Beatriz , Prieto-Pérez Laura , de la Cuadra-Grande Alberto , Casado Miguel Ángel , Cabello Úbeda Alfonso , Al-Hayani Aws W. , Carrillo Acosta Irene , Mahillo-Fernández Ignacio , Górgolas Hernández-Mora Miguel , Benito Jose M. , Rallón Norma
Published: July 2024

Objective: To determine whether HIV-infected individuals versus individuals with HIV/HCV coinfection, in the era of interferon-free therapies, exhibit an increased incidence of comorbidities and non-AIDS-related events. Methods: A retrospective analysis was conducted by collecting data from clinical records of Spanish patients at a tertiary hospital involving HIV/HCV-coinfected and HIV-infected patients, all with effectively controlled HIV. Coinfected patients underwent HCV clearance using direct-acting antivirals (DAAs) and had no history of interferon treatment. The incidences of hypertension, diabetes mellitus, cardiovascular disease, kidney disease, liver disease, non-AIDS cancer, and death were compared between the groups. Multivariate adjustments for all factors potentially impacting outcomes were used to assess the risk of clinical event onset. Propensity score (PS) analyses were also conducted to support the multivariate model results. Results: Data were available from 229 HIV/HCV-coinfected patients and 229 HIV-infected patients. Both cohorts were comparable in terms of age, gender distribution, follow-up, and HIV-related characteristics. Multivariate models and PS showed that previous exposure to HCV was not associated with the onset of any clinical events studied. Significant differences between HIV/HCV-coinfected and HIV-infected were not found for survival according to the log-rank test (p = 0.402). Conclusions: Successful HCV elimination using DAAs improved the outlook regarding comorbidities and survival across HIV/HCV-coinfected cohorts. Early HCV detection and DAA therapy could enhance clinical results. These findings provide an optimistic perspective for those living with HIV/HCV coinfection and underscore the importance of continuing efforts toward early detection and DAA treatment initiation.
The Effects of Vibegron Add-on Therapy on Alpha 1-Blocker Therapy for Sexual Function and Overactive Bladder Symptoms in Benign Prostatic Hyperplasia: A Prospective, Open-Label Study
Authors: Yanagida Kazuki , Watanabe Daisuke , Yoshida Takahiro , Mizushima Akio , Nakagawa Tohru
Published: July 2024

Background: The effect of combining an α1-adrenergic receptor blocker (α1-blocker) and the β3-adrenoceptor agonist vibegron for treating persistent overactive bladder (OAB) symptoms associated with benign prostatic hyperplasia (BPH) on sexual function remains uncertain. Therefore, we aimed to evaluate the effects of vibegron as an add-on to α1-blocker therapy on both OAB and sexual function. Methods: Forty-three patients with BPH in whom OAB symptoms were inadequately controlled by α1-blocker treatment were included in this prospective open-label study. The OAB Symptom Score (OABSS), International Prostate Symptom Score (IPSS), 15-item International Index of Erectile Function (IIEF-15), and Erection Hardness Score (EHS), as well as the residual urine volume and serum-free testosterone (FT) and C-reactive protein (CRP) levels, were evaluated before and 8 weeks after the daily administration of 50 mg vibegron/α1-blocker combination therapy. Results: Vibegron/α1-blocker combination therapy significantly improved the OABSS (from 6.9 ± 2.6 to 5.1 ± 2.9, p < 0.0001) and IIEF intercourse satisfaction domain (from 1.1 ± 2.3 to 1.9 ± 2.6, p = 0.02). No significant differences were observed for the IPSS, EHS, total IIEF-15 score, residual urine volume, and serum FT and CRP levels. Conclusions: The study findings suggest that vibegron/α1-blocker combination therapy improves OAB and sexual satisfaction.
Impact of Dental Midline Shift on the Perception of Facial Attractiveness in Young Adults
Authors: Sayahpour Babak , Eslami Sara , Usherenko Ralf , Jamilian Abdolreza , Gonzalez Balut Mauricio , Plein Nicolas , Grassia Vincenzo , Nucci Ludovica
Published: July 2024

Background/Objectives: The aim of this study was to quantify the threshold of a dental midline shift that would compromise facial attractiveness and indicate a need for treatment from the points of view of laypeople and dental professionals. Methods: Whole-face natural photographs of a male and a female model were digitally manipulated to create various degrees of upper and lower dental midline shifts through bodily movement of the upper or lower midlines as well as alteration of the axial inclination of the upper teeth. The samples were then assessed by two groups of observers (laypeople (LP) and dental professionals (DP)). Results: The lower midline shift did not negatively affect the DP and LP’s perceptions of smile attractiveness. The first significant loss of attractiveness was registered by the DP with an upper midline shift of 1 mm in the female model. However, the LP registered this at 2 mm. The DP registered the necessity of treatment at a threshold of 2 mm in the female model and 3 mm in the male model. LP identified the need for treatment at 3 mm for both males and females. The female model was judged more critically than her male counterpart by both female and male observers. Conclusions: DP assess the midline deviation more critically than LP. Both DP and LP were more sensitive to midline deviations in the female model regardless of their own gender. Both groups registered the need for treatment at a higher threshold than the reduction in smile attractiveness.
Is Type and Grade of Emphysema Important for Bone Mineral Density and Aortic Calcifications?
Authors: Vuković Danica , Budimir Mršić Danijela , Ordulj Ivan , Šarić Frano , Tandara Mirko , Jerković Kristian , Matana Antonela , Tadić Tade
Published: July 2024

Background: Chronic obstructive pulmonary disease has extrapulmonary manifestations, such as cardiovascular diseases and osteoporosis. The purpose of this research was to determine the relationship between the type and extent of emphysema with thoracic aorta calcification (TAC) and bone mineral density (BMD) at Th4, Th8, and L1 vertebrae. Methods: Emphysema was described by computed tomography parameters (both Fleischner classification and low attenuation value percentage, LAV%) and the clinical FEV1/FVC ratio (Tiffeneau–Pinelli index, TI, TI < 0.7; TI > 0.7). Results: Of 200 included patients (median age 64, 33% women), signs of clinical obstruction (TI) were observed in 104 patients, which had significantly lower BMD and more heavy TAC. BMD correlated negatively with LAV%, Rho = −0.16 to −0.23, while a positive correlation of aortic calcification with LAV% was observed, Rho = 0.30 to 0.33. Multiple linear regression showed that age and TI < 0.7 were independent predictors of BMD, β = −0.20 to −0.40, and β = −0.21 to −0.25; age and hypercholesterolemia were independent predictors of TCA, β = 0.61 and β = 0.19. Conclusions: Clinical TI and morphological LAV% parameters correlated with BMD and TAC, in contrast to Fleischer-graded emphysema, which showed no correlation. However, only TI was an independent predictor of BMD, while the morphologically described type and extent of emphysema could not independently predict any extrapulmonary manifestation.
Chitosan–Gelatin Scaffolds Loaded with Different Antibiotic Formulations for Regenerative Endodontic Procedures Promote Biocompatibility and Antibacterial Activity
Authors: Alghofaily Maha , Almana Aljowhara , Alrayes Jenan , Lambarte Rhodanne , Weir Michael D. , Alsalleeh Fahd
Published: July 2024

Background: This study investigated the biocompatibility and antibacterial efficacy of chitosan–gelatin (CH-G) scaffolds loaded with slow-releasing antibiotic formulations used in regeneration endodontic procedures (REPs). Methods: Scaffolds were fabricated using freeze drying and loaded with varying concentrations of augmentin or modified triple antibiotic paste (mTAP). High-resolution scanning electron microscopy (SEM) was used to characterize the scaffold, while drug release was monitored via UV-Vis spectrophotometry. Immortalized human mesenchymal stem cells (hMSCs) were cultured on CH-G scaffolds alone (control), either 0.1 mg/mL or 1 mg/mL of augmentin or mTAP, and 10 mg/mL calcium hydroxide (Ca(OH)2). Cell viability and proliferation were assessed using the Alamar Blue assay and SEM, respectively, and live/dead staining further corroborated cell viability. Antibacterial activity against Enterococcus faecalis was evaluated using the MTT assay and confocal laser scanning microscopy (CLSM). Results: Augmentin at 0.1 mg/mL appeared to promote better cell growth and attachment within the scaffolds than all other formulations, exhibiting acceptable viability. SEM revealed improved cell attachment in augmentin and mTAP groups compared to the Ca(OH)2 group. Augmentin at 1 mg/mL and mTAP groups significantly reduced viable bacteria compared to controls. Augmentin groups and mTAP at 1 mg/mL were highly effective in eliminating E. faecalis biofilms, with mTAP potentially causing more cell death within the remaining biofilm structures. Conclusions: This study suggests that CH-G scaffolds loaded with augmentin and mTAP, particularly at a concentration of 1 mg/mL, offer promising advantages for REPs due to their biocompatibility, antibacterial efficacy, and ability to promote cell attachment. Further research may explore the long-term effects in clinical settings.
Synergistic Effect of Polyethylene Glycol and Lactic Acid on Handling Properties and Antibacterial Efficacy of Premixed Calcium Silicate Cement
Authors: Huang Yi-Huei , Wu I-Ting , Chen Chun-Cheng , Ding Shinn-Jyh
Published: July 2024

Calcium silicate (CaSi) bone cement with antibacterial and osteogenic properties has attracted significant interest. However, there is a need to develop a variety of new premixed bone cement to meet the clinical requirements of fast setting time, ease of handling, and efficient antibacterial properties. In this study, different volume ratios of polyethylene glycol (PEG) and lactic acid liquids were added to calcium silicate, and the effects of varying liquid-to-powder ratios (L/P) were examined. This study assessed the physicochemical properties, cytotoxicity, and antibacterial activity against S. aureus and E. coli of this premixed cement. The results from the experiments indicated that lactic acid significantly reduced the setting time of the CaSi-based cement and enhanced its mechanical strength. Furthermore, the appropriate concentration of lactic acid and matching L/P ratio improved its washout resistance. The cell viability of all premixed cement was found to be over 80%. The premixed cement containing PEG and lactic acid exhibited superior antibacterial properties compared to the CaSi control. Based on its setting time, washout resistance, and antibacterial activity, a premixed cement with a liquid phase of 80% PEG and 20% lactic acid at an L/P ratio of 0.4 appeared promising for use in dental and orthopedic practice.
Development of a Control System for Underwater Vehicles with Multilink Manipulators Performing Contact Manipulation Operations
Authors: Konoplin Alexander , Krasavin Nikita , Yurmanov Alexander , Piatavin Pavel , Vasilenko Roman , Panchuk Maxim
Published: July 2024

This article proposes a new method for the synthesis of autonomous underwater vehicles (AUVs) with a multilink manipulators control system, which provides for the automatic execution of contact manipulation operations by AUVs in stabilized hovering mode near or above target objects. To achieve the desired magnitude of the working tool’s force effect on the object surface, the force vector exerted by this tool is calculated. Next, control signals providing additional movements of the manipulator’s tool in the direction of the desired force vector are generated. Simultaneously, based on the calculated effects from the manipulator on the AUV, the thrusts of the latter’s thrusters create the necessary pull at the manipulator’s attachment point, which allows it to exert the desired force effects on the object surface. To compensate for the inevitable AUV stabilization system errors, leading to the tool’s deviations from the trajectory, the latter is automatically corrected, taking into account the actual AUV deviations. As a result, contact manipulation operations are performed while maintaining the continuous contact of the tool with the object, even with slight displacements of the AUV from the stabilization point. The operability and efficiency of the synthesized system are confirmed by the results of numerical modeling, with the use of basin experimental data and visualization.
Timescales for the Spray-Mediated Gas Exchange of Carbon Dioxide
Authors: Hendrickson Lucy , Vlahos Penny , Romero Leonel
Published: July 2024

The air–sea exchange of carbon dioxide (CO2) on a global scale is a key factor in understanding climate change and predicting its effects. The magnitude of sea spray’s contribution to this flux is currently highly uncertain. Constraining CO2’s diffusion in sea spray droplets is important for reducing error margins in global estimates of oceanic CO2 uptake and release. The timescale for CO2 gas diffusion within sea spray is known to be shorter than the timescales for the droplets’ physical changes to take place while aloft. However, the rate of aqueous carbonate reactions relative to these timescales has not been assessed. This study investigates the timescales of droplet physical changes to those of chemical transformations across the H2CO3/HCO3−/CO32− sequence. We found that physical timescales are rate limiting and that evaporation drives carbonate species into gaseous CO2, promoting the production and evasion of CO2 from sea spray droplets. This has important implications for carbon cycling and feedback in the surface ocean.
Artificial Reef Design and Flow Field Analysis for Enhancing Stichopus japonicus Cultivation in Haizhou Bay
Authors: Lai Junlin , Yang Feifei , Huang Dazhi , Huang Siqi , Sun Xiaojie
Published: July 2024

In recent years, with the scale and standardization of Stichopus japonicus mariculture, artificial reefs are increasingly used in S. japonicus farming to promote the development of the S. japonicus aquaculture industry. To provide shelter and improve the habitat environment for S. japonicus, three types of artificial reefs (box-shaped reef, triangular-shaped reef, and trapezoidal-shaped reef) were designed according to the ecological habitats of S. japonicus and the marine environment of Haizhou Bay (China) in the present study. After comprehensively comparing the three reef structures, we found that the trapezoidal-shaped reef has good permeability, a larger attachment area, and excellent anti-slip and anti-overturning properties. Further, the flow field characteristics surrounding a trapezoidal-shaped reef at different angles and flow velocities are investigated by three-dimensional numerical simulations. Then, the impact of the placement distance on the flow field surrounding the artificial reef combination was investigated. At the head-on angle θ = 0°, the upwelling volume increases as the flow velocity increases and then decreases, and the back eddy volume remains relatively constant. At the longitudinal spacing D = 4 L, the large slow-flow area surrounding the reef under this condition is more suitable for the S. japonicus habitat. In this study, the trapezoidal-shaped reef design is suitable and beneficial for S. japonicus aquaculture. Moreover, this study will contribute theoretical references to the design and arrangement of artificial reefs in coastal areas.
Biological and Environmental Impact of Pharmaceuticals on Marine Fishes: A Review
Authors: Punginelli Diletta , Maccotta Antonella , Savoca Dario
Published: July 2024

Pharmaceuticals are recognized as a serious threat to aquatic ecosystems due to their persistence or pseudo-persistence and their biological activity. Their increased consumption in human and animal medicine has led to a continuous discharge of such biologically active molecules in aquatic environments. Marine ecosystems have been poorly investigated, even though recent studies have confirmed that these emerging contaminants occur widely in these ecosystems. Due to their interaction with specific biochemical and physiological pathways in target organisms, pharmaceuticals can cause alterations in several marine species during their entire life cycle. In particular, marine fishes have shown the ability to bioaccumulate these compounds in their body, and they may be used as potential bioindicators of pharmaceutical contamination in seawater. The objective of this review was to provide a comprehensive overview of the current understanding of the sources and occurrence of pharmaceuticals in marine environments, illustrating the adverse biological effects of important classes of these compounds on marine fishes.
Enhancing the Accessibility of Pedestrian Environments: Critical Reflections on the Role of the Public Sector Equality Duty
Authors: Lawson Anna , Orchard Maria , Eskyte Ieva , Campbell Morgan
Published: July 2024

The British Equality Act 2010’s Public Sector Equality Duty (PSED) aims to mainstream equality into the decision-making of public authorities. Although it has generated substantial critique, it has been the subject of surprisingly few empirical investigations, and existing literature does not address the role of the PSED in enhancing accessibility—either in the specific context of streetscapes or more generally. Here, we present the findings of a doctrinal and qualitative study on this topic. It consists of a critical review of relevant case law and an empirical study in which we interviewed disability campaigners, lawyers, and people working in or for public authorities. Two broad issues emerged from the empirical investigation: involvement and enforcement—on each of which our interviewees identified a range of concerns. These, together with our critique of case law, inform our analysis of the impact and effectiveness of the PSED in the context of streetscape accessibility, and accessibility more broadly. We conclude that, while the PSED (together with other Equality Act duties) is charged with a critical role in embedding equality—and, therefore, accessibility—in public authority decision-making, various factors have severely hampered its ability to deliver. Accessibility too often appears to be subordinated to other policy agendas instead of being embedded within them. There is an urgent need for reform to ensure that accessibility is suitably prioritised—both generally and in the particular context of streetscapes.
Assessing the Potential of Bio-Based Friction Modifiers for Food-Grade Lubrication
Authors: Nothnagel Rosa Maria , Boidi Guido , Franz Rainer , Frauscher Marcella
Published: July 2024

The objective of this research is to identify a bio-based friction modifier (FM) with tribological performance comparable to conventional FMs. Promising alternatives to conventional FMs, such as the FMs derived from natural sources, including rapeseed and salmon oil, were selected. Increasing concerns about crude oil prices, environmental impact, and the depletion of fossil resources have further fueled the search for renewable, biodegradable, and environmentally friendly raw materials for lubricants Tribological tests were conducted using a rheometer under non-conformal contact. The normal force, temperature, and sliding speed were varied to simulate conditions such as those found in a food extruder. To simulate cold extrusion applications, water and bio-based FM mixtures were used. The best-performing bio-based FMs were then mixed with a polyalphaolefin to simulate warm extrusion conditions. The results were compared to those obtained from mixtures of a polyalphaolefin and selected conventional FMs. The main finding of this study demonstrated that rapeseed and salmon oils, with a peak coefficient of friction (COF) of 0.16, are the best-performing bio-based FMs for reducing friction. When mixed with distilled water for cold extrusion (case 1) and with polyalphaolefin for warm extrusion (case 2), they performed similarly to the conventional FM, tallow amine, also with a maximum COF of 0.16, and significantly better than polyalphaolefin alone (maximum COF of 0.25). Consequently, rapeseed and salmon oils are suitable bio-based FM candidates to replace conventional FMs in food-grade lubrication.
Multi-Response Optimization and Experimental Investigation of the Influences of Various Coolant Conditions on the Milling of Alloy 20
Authors: Zhao Youlei , Cui Na , Hou Zhenxian , Li Jing , Liu Junqiang , Xu Yapeng
Published: July 2024

This study investigates the machining processes of Alloy 20 under different cooling conditions: Minimum Quantity Lubrication (MQL), Carbon Dioxide (CO2), and the hybrid MQL + CO2 approach. The research focuses on optimizing the cutting parameters, understanding the surface characteristics, analysing the tool wear patterns, and evaluating the chip formation. Face-centred CCD-based response surface methodology (RSM) is applied in order to identify the optimized cutting conditions. Surface roughness, tool wear, and chip morphology are examined through SEM imaging. Surface roughness characteristics reveal distinctive characteristics for each coolant condition: MQL cooling results in a relatively rough surface with tool nose degradation, CO2 cooling shows scratches on the surface and tool chipping, and MQL + CO2 cooling yields a smoother finish with close and continuous chip formation under the optimized conditions. This study contributes valuable insights into the complex interactions between cutting parameters and coolants, aiding in the optimization of machining processes for improved outcomes of the machining of Alloy 20. Based on the RSM outcomes, the optimal parametric settings obtained are Vc = 44 m/min, f = 0.04 mm/rev, and ap = 0.43 mm.
Physics-Informed Online Learning for Temperature Prediction in Metal AM
Authors: Sajadi Pouyan , Rahmani Dehaghani Mostafa , Tang Yifan , Wang G. Gary
Published: July 2024

In metal additive manufacturing (AM), precise temperature field prediction is crucial for process monitoring, automation, control, and optimization. Traditional methods, primarily offline and data-driven, struggle with adapting to real-time changes and new process scenarios, which limits their applicability for effective AM process control. To address these challenges, this paper introduces the first physics-informed (PI) online learning framework specifically designed for temperature prediction in metal AM. Utilizing a physics-informed neural network (PINN), this framework integrates a neural network architecture with physics-informed inputs and loss functions. Pretrained on a known process to establish a baseline, the PINN transitions to an online learning phase, dynamically updating its weights in response to new, unseen data. This adaptation allows the model to continuously refine its predictions in real-time. By integrating physics-informed components, the PINN leverages prior knowledge about the manufacturing processes, enabling rapid adjustments to process parameters, geometries, deposition patterns, and materials. Empirical results confirm the robust performance of this PI online learning framework in accurately predicting temperature fields for unseen processes across various conditions. It notably surpasses traditional data-driven models, especially in critical areas like the Heat Affected Zone (HAZ) and melt pool. The PINN’s use of physical laws and prior knowledge not only provides a significant advantage over conventional models but also ensures more accurate predictions under diverse conditions. Furthermore, our analysis of key hyperparameters—the learning rate and batch size of the online learning phase—highlights their roles in optimizing the learning process and enhancing the framework’s overall effectiveness. This approach demonstrates significant potential to improve the online control and optimization of metal AM processes.
Effect of Solution-to-Binder Ratio and Molarity on Volume Changes in Slag Binder Activated by Sodium Hydroxide at Early Age
Authors: Lacante Maïté , Delsaute Brice , Staquet Stéphanie
Published: July 2024

This research investigates the impact of solution concentration and solution-to-binder ratio (S/B) on the volume changes in alkali-activated slags with sodium hydroxide at 20 °C. Autogenous and thermal strains are monitored with a customized testing device in which thermal variations are controlled. Consequently, both the autogenous strain and coefficient of thermal expansion (CTE) are determined. Heat flow and internal relative humidity (IRH) are also monitored in parallel, making this research a multifaceted study. The magnitudes of autogenous strain and CTE are higher than those of ordinary Portland cement paste. Decreasing the solution concentration or S/B generally decreases the autogenous strain (swelling and shrinkage) and the CTE. The shrinkage amounted to 87 to 1981 µm/m, while the swelling reached between 27 and 295 µm/m and was only present in half of the compositions. The amplitude of the CTE, which increases up to 55 µm/m/°C for some compositions while the CTE of OPC remains between 20 and 25 µm/m/°C, can be explained by the high CTE of the solution in comparison with water. The IRH of paste cannot explain the autogenous strain’s development alone. Increasing S/B eliminates the self-desiccation-related decrease.
Low-Temperature Superplasticity of Ultrafine-Grained Aluminum Alloys: Recent Discoveries and Innovative Potential
Authors: Bobruk Elena V. , Zaripov Nail G. , Ramazanov Ilnar A. , Chinh Nguyen Q. , Valiev Ruslan Z.
Published: July 2024

The last two decades have witnessed significant progress in the development of severe plastic deformation techniques to produce ultrafine-grained materials with new and superior properties. This review examines works and achievements related to the low-temperature superplasticity of ultrafine-grained aluminum alloys. The examples are provided of the possibility to observe low-temperature superplasticity in aluminum alloys at temperatures less than 0.5 Tmelt and even at room temperature, and herein, we demonstrate the cases of achieving high ductility and high strength in aluminum alloys from processing utilizing severe plastic deformation. Special emphasis is placed on recent studies of the formation of segregations of alloying elements at grain boundaries in UFG Al alloys and their influence on the development of grain boundary sliding and manifestation of low-temperature superplasticity. In addition, the current status and innovative potential of low-temperature superplasticity in aluminum alloys are observed.
Insight into the Extractive Metallurgy of Tin from Cassiterite
Authors: Fosu Allen Yushark , Bartier Danièle , Diot Frédéric , Kanari Ndue
Published: July 2024

This review details both the conventional and emerging methods of extracting tin from cassiterite. The emerging methods reviewed include sulphuric acid leaching of SnO, cooling crystallization of SnO, sulphide leaching, alkaline leaching, and dry chlorination. From these methods, the conventional approach (direct reduction smelting) stands out as the sole method that is suitable for industrial application, with none of the emerging ones being promising enough to be a contender. The thermodynamics involved in the hydrometallurgical extraction of tin from the mineral are also discussed. ΔGo values calculated at 25 °C for the reduction–dissolution of SnO2 using reducing gases revealed feasibility only when carbon monoxide was used. An indication of the possible species produced during the hydrolysis of the oxide of the metal (SnO2 and SnO) as a function of pH (ranging from −2 to 14 and 0 to 14 for SnO2 and SnO, respectively) was noted and highlighted to link a Pourbaix diagram generated from literature data. This diagram suggests that the solubility of SnO2 in both strongly acidic and alkaline media is possible, but with a small dissolution window in each. The purification and recovery routes of the various processing techniques were then envisaged.
Study on Mechanical Properties of Nanopores in CoCrFeMnNi High-Entropy Alloy Used as Drug-Eluting Stent
Authors: Zhou Zhen , Ji Chaoyue , Hou Dongyang , Jiang Shunyong , Yang Zihan , Dong Fang , Liu Sheng
Published: July 2024

The CoCrFeMnNi high-entropy alloy is commonly used for vascular stents due to its excellent mechanical support and ductility. However, as high-entropy alloy stents can cause inflammation in the blood vessels, leading to their re-narrowing, drug-eluting stents have been developed. These stents have nanopores on their surfaces that can carry drug particles to inhibit inflammation and effectively prevent re-narrowing of the blood vessels. To optimize the mechanical properties and drug-carrying capacity of high-entropy alloy stents, a high-entropy alloy system with different wide and deep square-shaped nanopore distributions is created using molecular dynamics. The mechanical characteristics and dislocation evolution mechanism of different nanopore high-entropy alloy systems under tensile stress were studied. The results showed that the CoCrFeMnNi high-entropy alloy with a rational nanopore distribution can effectively maintain the mechanical support required for a vascular stent. This research provides a new direction for the manufacturing process of nanopores on the surfaces of high-entropy alloy stents.
Effects of Heat Input and Intertrack Overlap on the Microstructure and Properties of Inconel 686 Weld Overlays
Authors: Tabaie Seyedmohammad , Khodamoradi Zahra , Greene Trevor , Benoit Michael J.
Published: July 2024

The objective of this study was to investigate how weld overlays with nickel superalloys are important for the integrity, due the high temperatures and corrosive environments that can be experienced in mineral processing environments, of mining and processing equipment. The Ni-Cr-Mo superalloy Inconel 686 overlays are fabricated through automatic gas metal arc welding with variations in arc voltage and travel speed (i.e., heat input), and they have overlap between adjacent weld tracks for applications in the mining and minerals sector. The impact of variations in the process parameters and the size of the weld overlapping on the dilution, solidification morphology, microsegregation, and microhardness were investigated. Both geometric and chemical composition definitions were used to quantify the extent of the weld dilution. Subsequently, the weld geometry and dilution were correlated with the solidification microstructure and phase transformations. The maximum dilutions were measured to be 13.63% (1/2 overlap, 5.96 kJ·cm−1) and 15.39% (1/3 overlap, 4.77 kJ·cm−1), which shows that less of an overlap increases the dilution level. Scanning electron microscopy and chemical composition analysis revealed that an increase in weld heat input and dilution level led to higher levels of microsegregation for Mo and Cr, as well as the volume fraction of Mo- and Cr-rich phases in the interdendritic/intercellular regions in the overlay layer. Analysis of the weld overlays in the current study revealed strong and unprecedented connections between the weld overlay process conditions, the resultant metallurgy (i.e., dendrite arm spacing, microsegregation, and phase formation), and the hardness of the overlay. It was concluded that the optimal weld overlays in the processing window studied in this investigation were fabricated at mid-level heat inputs (i.e., 4–5 kJ·cm−1) and a 1/2 track overlap.
A 3D Elastoplastic Constitutive Model Considering Progressive Damage Behavior for Thermoplastic Composites of T700/PEEK
Authors: Fu Weigang , Xiong Huanjie , Liao Zhe , Ma Junchi , Fu Yaoming , Wang Bin
Published: July 2024

Due to their excellent mechanical properties, the carbon fiber-reinforced polymer composites (CFRPs) of thermoplastic resins are widely used, and an accurate constitutive model plays a pivotal role in structural design and service safety. A two-parameter three-dimensional (3D) plastic potential was obtained by considering both the deviatoric deformation and the dilatation deformation associated with hydrostatic stress. The Langmuir function was first adopted to model the plastic hardening behavior of composites. The two-parameter 3D plastic potential, connected to the Langmuir function of plastic hardening, was thus proposed to model the constitutive behavior of the CFRPs of thermoplastic resins. Also, T700/PEEK specimens with different off-axis angles were subjected to tensile loading to obtain the corresponding fracture surface angles of specimens and the load–displacement curves. The two unknown plastic parameters in the proposed 3D plastic potential were obtained by using the quasi-Newton algorithm programmed in MATLAB, and the unknown hardening parameters in the Langmuir function were determined by fitting the effective stress-plastic strain curve in different off-axis angles. Meanwhile, the user material subroutine VUMAT, following the proposed constitutive model, was developed in terms of the maximum stress criterion for fiber failure and the LaRC05 criterion for matrix failure to simulate the 3D elastoplastic damage behavior of T700/PEEK. Finally, comparisons between the experimental tests and the numerical analysis were made, and a fairly good agreement was found, which validated the correctness of the proposed constitutive model in this work.
On the Feasibility of an LCD-Based Real-Time Converter for Ionizing Radiation Imaging
Authors: Januszko Adam , Zych Eugeniusz , Piecek Wiktor , Pellowski Witalis , Bogdanowicz Krzysztof A. , Iwan Agnieszka
Published: July 2024

Here we present the cascade converter (CC), which provides real-time imaging of ionizing radiation (IoR) distribution. It was designed and manufactured with the simplest architecture, utilizing liquid crystal display (LCD) technology. Based on two merged substrates with transparent electrodes, armed with functional layers, with the cell filled with nematic liquid crystal, a display-like, IoR-stimulated CC was achieved. The CC comprises low-absorbing polymer substrates (made of polyethylene terephthalate—PET) armed with a transparent ITO electrode covered with a thin semipermeable membrane of polymer (biphenylperfluorocyclobutyl: BP-PFCB) doped with functional nanoparticles (NPs) of Lu2O3:Eu. This stack was covered with a photoconductive layer of α-Se and finally with a thin polyimide (PI) layer for liquid crystal alignment. The opposite substrate was made of LCD-type glass with ITO and polyimide aligning layers. Both substrates form a cell with a twisted structure of nematic liquid crystal (TN) driven with an effective electric field Eeff. An effective electric field driving TN structure is generated with a sum of (1) a bias voltage VBIAS applied to ITO transparent electrodes and (2) the photogenerated additional voltage VXray induced between ITO and α-Se layers with a NPs-doped BP-PFCB polymer layer in-between. The IoR (here, X-ray) conversion into real imaging of the IoR distribution was achieved in the following stages: (1) conversion of IoR distribution into non-ionizing red light emitted with functional NPs, (2) transformation of red light into an electric charge distributed in a layer of the photoconductive α-Se, which is what results in the generation of distributed voltage VXray, and (3) a voltage-mediated, distributed switching of the TN structure observed with the naked eye. The presented imaging device is characterized by a simple structure and a simple manufacturing process, with the potential for use as a portable element of IoR detection and as a dosimeter.
Acoustic Assessment of Microstructural Deformation Mechanisms on a Cold Rolled Cu30Zn Brass
Authors: Sosa María , Carvajal Linton , Salinas Barrera Vicente , Lund Fernando , Aguilar Claudio , Castro Cerda Felipe
Published: July 2024

The relationship between acoustic parameters and the microstructure of a Cu30Zn brass plate subjected to plastic deformation was evaluated. The plate, previously annealed at 550 °C for 30 min, was cold rolled to reductions ranging from 10% to 70%. Linear ultrasonic measurements were performed on each of the nine specimens, corresponding to the nine different reductions, using the pulse-echo method to record the times of flight of longitudinal waves along the thickness axis. Subsequently, acoustic measurements were conducted to determine the nonlinear parameter β through second harmonic generation. Microstructural analysis, carried out by X-ray diffraction, Vickers hardness testing, and optical microscopy, revealed an increase in deformation twins, reaching a maximum at 40% thickness reduction. At higher deformations, the microstructure showed the generation and proliferation of shear bands, coinciding with a decrease in the twinning structure and an increase in dislocation density. The longitudinal wave velocity exhibited a 0.9% decrease at 20% deformation, attributed to dislocations and initial twin formation, followed by a continuous increase up to 2% beyond this point, resulting from the combined effects of twinning and shear banding. The nonlinear parameter β displayed a notable maximum, approximately one order of magnitude greater than its original value, at 40% deformation. This peak correlates with a roughly tenfold increase in twinning fault probability at the same deformation level.