bluuebunny/crossref_metadata_2025 huggingface dataset:
Range-Domain Subspace Detector in the Presence of Direct Blast for Forward Scattering Detection in Shallow-Water Environments
Authors: Luo Jiahui , Sun Chao , Li Mingyang
Published: October 2024

This paper aims to detect a target that crosses the baseline connecting the source and the receiver in shallow-water environments, which is a special scenario for a bistatic sonar system. In such a detection scenario, an intense sound wave, known as the direct blast, propagates directly from the source to the receiver without target scattering. This direct blast usually arrives at the receiver simultaneously with the forward scattering signal and exhibits a larger intensity than the signal, posing a significant challenge for target detection. In this paper, a range-domain subspace is constructed by the horizontal distance between the source/target and each element of a horizontal linear array (HLA) when the ranges of environmental parameters are known a priori. Meanwhile, a range-domain subspace detector based on direct blast suppression (RSD-DS) is proposed for forward scattering detection. The source and the target are located at different positions, so the direct blast and the scattered signal are in different range-domain subspaces. By projecting the received data onto the orthogonal complement subspace of the direct blast subspace, the direct blast can be suppressed and the signal that lies outside the direct blast subspace is used for target detection. The simulation results indicate that the proposed RSD-DS exhibits a performance close to the generalized likelihood ratio detector (GLRD) while requiring less prior knowledge of environments (only known are the ranges of the sediment sound speed and the bottom sound speed), and its robustness to environmental uncertainties is better than that of the latter. Moreover, the proposed RSD-DS exhibits better immunity against the direct blast than the GLRD, since it can still work effectively at a signal-to-direct blast ratio (SDR) of −30 dB, while the GLRD stops working in this case.
An Investigation into Using CFD for the Estimation of Ship Specific Parameters for the SPICE Model for the Prediction of Sea Spray Icing: Part 2—The Verification of SPICE2 with a Full-Scale Test
Authors: Sundsbø Per-Arne , Deshpande Sujay
Published: October 2024

A hybrid CFD–ML model for the prediction of sea spray icing, SPICE2, was developed in Part 1 of this study in Deshpande et al., 2024. The SPICE2 model is an extension of the ML model, SPICE, where some of the variables required for icing rate predictions: local wind speed, spray duration, spray period, and spray flux, are computed from CFD simulations. These, along with the air and water temperatures, and the salinity from the metocean data are used for the prediction of icing rates at different locations on a moving vessel. The existing full-scale icing measurements proved to be not detailed enough for the purpose of the verification of sea spray icing prediction models and the verification of the SPICE2 required distribution of sea spray icing data on the vessel surface in addition to the vessel design for simulation. A full-scale sea spray icing test was conducted in 2018 by Sundsbø et al. on a fully enclosed lifeboat equipped for the Goliat field in the Barents Sea. The 3D design of the same lifeboat, together with the corresponding metocean conditions and ship characteristics was used for the simulation of the vessel-specific parameters required for the verification of the icing rate and distribution prediction from the SPICE2 model against the measured distribution of sea spray icing rates on the lifeboat surface. The availability of the 3D model of this lifeboat, in addition to the fact that the icing measurements from this test were detailed enough to attempt a model verification served the purpose of validating the SPICE2 model. The icing rates measured on this lifeboat are used for the full-scale validation of the SPICE2 model that is proposed in Part 1 of this study. It was seen that the icing rates predicted by SPICE2 concurred with 9 of 13 selected locations on the lifeboat. The ones which did not showed very little deviation from the measurements. The icing rate and distribution prediction with SPICE2 were satisfactorily validated against full-scale icing measurements. This is a first attempt in modelling sea spray generation using CFD and further research into CFD for the estimation of spray flux is suggested.
Improved Fracture Permeability Evaluation Model for Granite Reservoirs in Marine Environments: A Case Study from the South China Sea
Authors: Guo Jianhong , Gu Baoxiang , Lv Hengyang , Zhu Zuomin , Zhang Zhansong
Published: October 2024

Permeability is a crucial parameter in the exploration and development of oil and gas reservoirs, particularly in unconventional ones, where fractures significantly influence storage capacity and fluid flow. This study investigates the fracture permeability of granite reservoirs in the South China Sea, introducing an enhanced evaluation model for planar fracture permeability based on Darcy’s law and Poiseuille’s law. The model incorporates factors such as fracture heterogeneity, tortuosity, angle, and aperture to improve permeability assessments. Building on a single-fracture model, this research integrates mass transfer equations and trigonometric functions to assess intersecting fractures’ permeability. Numerical simulations explore how tortuosity, angle, and aperture affect individual fracture permeability and the influence of relative positioning in intersecting fractures. The model makes key assumptions, including minimal consideration of horizontal stress and the assumption of unidirectional laminar flow in cross-fractures. Granite outcrop samples were systematically collected, followed by full-diameter core drilling. A range of planar models with varying fracture apertures were designed, and permeability measurements were conducted using the AU-TOSCAN-II multifunctional core scanner with a steady-state gas injection method. The results showed consistency between the improved model and experimental findings regarding the effects of fracture aperture and angle on permeability, confirming the model’s accuracy in reflecting the fractures’ influence on reservoir flow capacity. For intersecting fractures, a comparative analysis of core X-ray computed tomography (X-CT) scanning results and experimental outcomes highlighted discrepancies between actual permeability measurements and theoretical simulations based on tortuosity and aperture variations. Limitations exist, particularly for cross-fractures, where quantifying complexity is challenging, leading to potential discrepancies between simulation and experimental results. Further comparisons between core experiments and logging responses are necessary for model refinement. In response to the challenges associated with evaluating absolute permeability in fractured reservoirs, this study presents a novel theoretical assessment model that considers both single and intersecting fractures. The model’s validity is demonstrated through actual core experiments, confirming the effectiveness of the single-fracture model while highlighting the need for further refinement of the dual-fracture model. The findings provide scientific support for the exploration and development of granite reservoirs in the South China Sea and establish a foundation for permeability predictions in other complex fractured reservoir systems, thereby advancing the field of fracture permeability assessment.
Evolving Consumer Preferences: The Role of Attribute Shifts in Online Travel Agency Satisfaction and Loyalty
Authors: Zhi Luyao , Ha Hong-Youl
Published: October 2024

The attributes that people consider when selecting an online travel agency (OTA) change over time, affecting how consumer satisfaction and loyalty evolve. However, attribute weight shifts in subsequent OTA visits cannot be determined using a cross-sectional approach. Thus, this study investigates the linkage dynamics between satisfaction and loyalty intentions as OTA attribute weights shift over time. We also assess the moderating effect of sales promotions on this linkage across subsequent OTA visits. Using a two-time-lag survey methodology (T1 and T2), we obtain 329 usable data. Our findings demonstrate that the link between satisfaction and loyalty intentions strengthens as customers gain more experience with an OTA. While price and post-service quality weights increase sharply, the weights of security and ease of use decrease. Furthermore, our findings show that the moderating effect of sales promotions does not appear in the early stages of a consumer’s experience with an OTA. Our research is the first to offer a complete understanding of the role of sales promotions based on the satisfaction–loyalty mechanism, considering a broad range of OTA selection attributes.
Identification of Spatial Patterns of Soil Erosion Based on the Combination of RUSLE and MCDA in the Ahferom District, Northern Ethiopia
Authors: Hailemariam Gebreslassie Welu , Zhao Jianlin , Moges Awdenegest
Published: October 2024

Soil erosion is a widespread concern that is indeed considered to be a significant environmental issue, and it has particularly severe consequences in less developed countries like Ethiopia. An effective watershed management procedure for establishing priority is supported by the identification of erosion-susceptible areas. Therefore, the main objective of the study was to assess soil erosion dynamics and its spatial pattern using a novel methodological framework combining the RUSLE and MCDA. The study used data on land use and cover, topography, soil, and climatic data. The analytical hierarchy process (AHP) were used to identify soil erosion-susceptible areas and the factors were weighted using a pairwise comparison matrix, and weights were combined using weighted overlay in GIS. Our results indicated that the mean annual soil loss rate was 27.10 t ha−1 yr−1, while the total soil loss from the entire study area was 3.11 Mt. The highest soil loss was observed in bare land (30.54 t ha−1 yr−1) and farmland (23.65 t ha−1 yr−1), which were considered as the most susceptible land types to erosion. Likewise, 10.3% of the study area is very highly susceptible; 20.2% is highly susceptible, 24.2% of the area is moderately susceptible, 27.1% is low, and 18.2% has very low susceptibility. The district’s most significant erosion-susceptible areas are characterized by steep slopes that are composed of farmland and bare land. This suggests the majority of the area is susceptible to erosion, requiring interventions to reverse the alarming degradation level. The presented framework has a board application to estimate regional soil erosion and to identify spatial patterns of soil erosion.
Assessing the Cooling Potential of Vegetation in a Central European Rural Landscape: A Local Study
Authors: Pohanková Tereza , Pechanec Vilém
Published: October 2024

This study investigates the cooling potential of vegetation in rural landscapes of the Czech Republic to mitigate heat-related issues. Using remote sensing, the Cooling Capacity Index (CCI) is assessed to measure green spaces’ ability to lower air temperatures using evapotranspiration and shading. Landsat 8/9 and meteorological data are utilised, with CCI calculated based on vegetation cover, albedo, and evapotranspiration. Our results demonstrate significant variations in cooling capacity across different land use types. Forests exhibited the highest cooling potential, while urban areas, characterised by heat-absorbing materials, displayed the least. We analysed temporal and spatial variations in cooling capacity using various visualisation tools and validated the results against the InVEST software (v3.14.0). This study highlights the effectiveness of remote sensing in quantifying ecosystem functions, particularly the cooling services provided by vegetation. Our findings emphasise the crucial role of vegetation in mitigating urban heat islands and addressing climate change. This research provides valuable insights for developing climate change adaptation strategies in rural landscapes.
Nature’s Neighborhood: The Housing Premium of Urban Parks in Dense Cities
Authors: Feng Siqi , Zhuo Yuefei , Xu Zhongguo , Chen Yang , Li Guan , Wang Xueqi
Published: October 2024

Urban parks, a core component of urban landscapes, play a crucial role in mitigating the negative effects of rapid urbanization and achieving sustainable urban development. In densely populated urban environments, providing urban parks fairly and efficiently, taking social preferences into account, is an important challenge. In this regard, we take Hangzhou, China, as an example and use a hedonic pricing model with a difference-in-differences estimator to test the effect of different types of urban parks on housing prices, quantify their respective economic values, and reflect homebuyers’ preferences. The findings indicate that the construction of new urban parks leads to an overall increase in the value of the surrounding real estate to some extent. Specifically, the construction of comprehensive parks and large parks significantly enhances the value of nearby housing, while proximity to new medium-sized parks also results in a housing price premium, albeit to a lesser extent. In contrast, community parks and specialized parks have a less significant impact on housing prices. These findings provide valuable insights for equitable urban development and planning, optimizing the allocation of urban parks and determining investment priorities for different types of parks to enhance the sustainability of the urban environment and human well-being.
Continuous Monitoring of Soil Respiration After a Prescribed Fire: Seasonal Variations in CO2 Efflux
Authors: Romero-Toribio María C. , Angulo Elena , Soriguer Ramón C. , Madrigal Javier , Senra-Rivero Francisco , Cerdá Xim , Cobos Joaquín
Published: October 2024

Prescribed burns have recently become a widespread environmental management practice for biodiversity restoration to reduce fuel load, to provide forest fire suppression operational opportunities, to favor plant recruitment or to manage wild species. Prescribed fires were again applied in Doñana National Park (southern Spain) after decades of non-intervention regarding fire use. Here, we assessed their impacts on the soil CO2 effluxes over two years after burning to test the hypothesis that if the ecosystem is resilient, soil respiration will have a rapid recovery to the conditions previous to the fire. Using soil automated CO2 flux chambers to continuously measure respiration in burned and unburned sites, we showed that soil respiration varies among seasons but only showed significant differences between burned and unburned plots in the fall season one year after fire, which corresponded with the end of the dry season. Comparing soil respiration values from the burned plots in the three fall seasons studied, soil respiration increased significantly in the fall one year after fire, but decreased in the following fall to the values of the control plots. This study highlights the resilience of soil respiration after prescribed fire, showing the potential benefits of prescribed fire to reduce catastrophic wildfires, especially in protected areas subjected to non-intervention.
A Methodological Framework to Enhance Potential Spatial Planning to Support Agroecological Transition at the Scale of Local Territories
Authors: Cénet Amélie , Viaud Valérie , Voisin Lolita
Published: October 2024

Agroecological transition requires research and actions at the scale of local territories, in which agricultural activities interact with the environment and natural resources depending on a territory’s spatial configuration. To support the agroecological transition, there is an urgent need to design and implement new spatial configurations. For this, local public authorities in France can be considered as an interesting level of governance, because of their skills in spatial planning and their interest in agriculture, to ensure the ecological transition of their territory. However, new methodological frameworks need to be developed to support the design of new spatial configurations of territories, by constructing representations of the territory that consider both agricultural and socio-environmental issues, and by involving agricultural and non-agricultural stakeholders so that both can project themselves into the new spatial configurations. We developed a new methodological framework at the interface between landscape agronomy and landscape architects’ approaches, and experimented with applying this framework in the Urban Community of Dunkirk (UCD), which was performing a spatial planning approach called a Landscape Plan and proposing to create an Agricultural Park. The results show that the implementation of the methodological framework enabled the construction of a spatially explicit and place-based representation including the spatial issues of farming systems. These representations enable a local authority’s stakeholders to enhance their knowledge of the agricultural issues and consider changes in the spatial configuration of the Agricultural Park. In the discussion, we question the adaptation of the framework in rural territory and highlight the limitations of local authorities as the level of governance at which to address the agroecological transition at the territorial scale.
Proteome Expression Signatures: Differences between Orbital and Subcutaneous Abdominal Adipose Tissues
Authors: Castel Noam , Vitkin Edward , Shabo Sharon , Berl Ariel , Wise Julia , Duenyas Amir , Cohen Eliyahu Michael Aharon , Golberg Alexander , Shalom Avshalom
Published: October 2024

Differences between orbital and subcutaneous abdominal fat in the same patient have been noted but not formally investigated, previously. The objective of this research was to compare the differential expression of protein profiles in subcutaneous abdominal and orbital adipose tissues. In this cross-sectional, observational study, orbital fat tissue was sampled from 10 patients who underwent blepharoplasty and agreed to provide a small sample of subcutaneous abdominal fat. Shotgun mass spectrometry was performed on the extracted proteome. Data were analyzed using protein appearance patterns, differential expression and statistical enrichment. Protein analysis revealed significant differences in proteomics and differential expression between the orbital and subcutaneous abdominal adipose tissues, which presented five proteins that were uniquely expressed in the orbital fat and 18 in the subcutaneous abdominal fat. Gene Ontology analysis identified significantly different cellular processes and components related to the extracellular matrix or basement membrane components. This analysis shows the differences between orbital and subcutaneous abdominal fat found in proteomics differential expression, uniquely expressed proteins, and cellular processes. Further research is needed to correlate specific proteins and cellular processes to the mechanism of fat accumulation and obesity.
30 Years of Change: Declining Motor Fitness and Anthropometric Shifts in Polish University Students (1994–2024)
Authors: Podstawski Robert , Borysławski Krzysztof
Published: October 2024

Background: To assess changes in the anthropometric and motor characteristics of male and female Polish university students between 1994 and 2024. Methods: The first study was conducted in 1994 on 712 female and 495 male university students aged 19–25 years (19.94 ± 1.09), and the second study was conducted in 2024 on 323 female and 339 male university students aged 19–25 years (19.92 ± 1.08). The participants’ body mass and height were measured, and the students participated in a modified version of Pilicz’s test consisting of four motor ability tests. The changes in the students’ performance over time were also analyzed in the context of their socioeconomic status (SES), including the place of permanent residence and the parents’ education. Results: The students’ BMI values (as well as body mass and body height in female students) were significantly higher (p < 0.001) in 2024 than in 1994. The male students examined in 1994 demonstrated significantly higher strength abilities in the medicine ball forward throw test. In turn, the females studied in 1994 received significantly better scores in motor ability tests, including the zig-zag run, 1-Minute Burpee Test, and the medicine ball forward throw (29.4 s, 22 cycles, 591.3 cm, respectively) than those examined in 2024 (30.1 s, 19.3 cycles, and 463.3 cm, respectively). The variations in the results were similar when the participants’ SES was considered in the analysis, which suggests that these factors had no significant effect on the analyzed characteristics over time. Conclusions: This study revealed a greater decline in the anthropometric and motor characteristics of female than male university students over a period of 30 years. The observed changes were not influenced by SES factors such as the place of permanent residence or the parents’ education.
Ion Beam-Induced Luminescence (IBIL) for Studying Manufacturing Conditions in Ceramics: An Application to Ceramic Body Tiles
Authors: Corregidor Victoria , Ruvalcaba-Sil José Luis , Prudêncio Maria Isabel , Dias Maria Isabel , Alves Luís C.
Published: October 2024

The first experimental results obtained by the ion beam-induced luminescence technique from the ceramic bodies of ancient tiles are reported in this work. The photon emission from the ceramic bodies is related to the starting minerals and the manufacturing conditions, particularly the firing temperature and cooling processes. Moreover, the results indicate that this non-destructive technique, performed under a helium-rich atmosphere instead of an in-vacuum setup and with acquisition times of only a few seconds, presents a promising alternative to traditional, often destructive, compositional characterisation methods. Additionally, by adding other ion beam-based techniques such as PIXE (Particle-Induced X-ray Emission) and PIGE (Particle-Induced Gamma-ray Emission), compositional information from light elements such as Na can also be inferred, helping to also identify the raw materials used.
Optimal Arrangements and Local Anisotropy of {100} Guinier–Preston (GP) Zones by Parametric Dislocation Dynamics (PDD) Simulations
Authors: Zheng Haiwei , Liu Jianbin , Muraishi Shinji
Published: October 2024

Stress-oriented precipitation and the resulting mechanical anisotropy have been widely studied over the decades. However, the local anisotropy of precipitates with specific orientations has been less thoroughly investigated. This study models the interaction between an edge dislocation source and {100} variants of Guinier–Preston (GP) zones in Al-Cu alloys using the parametric dislocation dynamics (PDD) method. Concentric geometrically necessary dislocation (GND) loops were employed to construct a line integral model for thin platelets. The simulations, conducted with our self-developed code based on Green’s function method and Eshelby inclusion theory revealed distinct strengthening behavior along the strong and weak directions for 60° GP zones, demonstrating anisotropic strengthening from the perspective of elastic interactions. Furthermore, the optimal inclined arrangement of the GP zone array was determined through elastic energy calculations, and these results were corroborated by TEM observations.
Single-Atom Underpotential Deposition at Specific Sites of N-Doped Graphene for Hydrogen Evolution Reaction Electrocatalysis
Authors: Wu Haofei , Zhang Qiwen , Chu Shufen , Du Hao , Wang Yanyue , Liu Pan
Published: October 2024

Single-atom catalysts (SACs) have the advantages of good active site uniformity, high atom utilization, and high catalytic activity. However, the study of its controllable synthesis still needs to be thoroughly investigated. In this paper, we deposited Cu SAs on nanoporous N-doped graphene by underpotential deposition and further obtained a Pt SAC by a galvanic process. Electrochemical and spectroscopic analyses showed that the pyridine-like N defect sites are the specific sites for the underpotential-deposited SAs. The obtained Pt SAC exhibits a good activity in a hydrogen evolution reaction with a turnover frequency of 25.1 s−1. This work reveals the specific sites of UPD of SAs on N-doped graphene and their potential applications in HERs, which provides a new idea for the design and synthesis of SACs.
Nanostructural Influence on Optical and Thermal Properties of Butterfly Wing Scales Across Forest Vertical Strata
Authors: López Queenny K. , Cárdenas Rafael E. , Ramírez Castro Francisco , Vizuete Karla , Checa María F. , Costa Vera César
Published: October 2024

Butterfly wing scales feature complex nanostructures that influence wing coloration and various mechanical and optical properties. This configuration plays a key role in ecological interactions, flight conditions, and thermoregulation, facilitated by interactions with environmental electromagnetic energy. In tropical forests, butterflies occupy distinct vertical habitats, experiencing significant light and temperature variations. While wing nanostructures have been widely studied, their variation across different vertical flight preferences remains underexplored. This study investigates the wing nanostructures of 12 tropical butterfly species from the Nymphalidae family, focusing on their optical, morphological, and thermal properties across different forest strata. We analyzed the optical response through diffuse reflectance in the UV, Vis, and NIR ranges, correlating these findings with nanostructural configuration and thermal stability using thermogravimetric analysis (TGA). Our results reveal a significant correlation between flight stratification and wing optical responses, alongside distinct nanostructural features within each stratum. This study demonstrates the variability in butterfly wing nanostructures along the vertical stratification of the forest to cope with environmental conditions, raising new questions for future research on eco-evolutionary flight and thermal adaptations. Additionally, this underscores the importance of understanding how these structural adaptations influence butterfly interactions with their environment and their evolutionary success across different forest strata.
Review of Laser Powder Bed Fusion’s Microstructure and Mechanical Characteristics for Al-Ce Alloys
Authors: Liu Yuanfan , Li Yang , Wang Mingliang , Chen Zhe
Published: October 2024

As a new alloy manufacturing method that can break through the limitations of molds to manufacture fine parts, laser powder bed fusion has recently become a common process for producing aluminum alloys. In the fields of aerospace or automotive, aluminum alloys with both good printability and good mechanical performance in high-temperature conditions are greatly demanded, and the Al-Ce alloy is one of the alloys with significant potential. Therefore, systematic research on the additive manufacturing of Al-Ce alloys is still being explored. Herein, we review the recent progress and current status of laser powder bed fusion-produced Al-Ce alloys, giving our opinions on the development of this alloy system. Element composition, alloy powders, laser powder bed fusion parameters, microstructures, and mechanical properties at room temperature and high temperatures are summarized. The choice of alloying strategies is crucial for a specific mechanical improvement of the Al-Ce alloys. Finally, the details of the Al-Ce alloys manufactured via laser powder bed fusion are presented.
Optimized Machine Learning Model for Predicting Compressive Strength of Alkali-Activated Concrete Through Multi-Faceted Comparative Analysis
Authors: Fang Guo-Hua , Lin Zhong-Ming , Xie Cheng-Zhi , Han Qing-Zhong , Hong Ming-Yang , Zhao Xin-Yu
Published: October 2024

Alkali-activated concrete (AAC), produced from industrial by-products like fly ash and slag, offers a promising alternative to traditional Portland cement concrete by significantly reducing carbon emissions. Yet, the inherent variability in AAC formulations presents a challenge for accurately predicting its compressive strength using conventional approaches. To address this, we leverage machine learning (ML) techniques, which enable more precise strength predictions based on a combination of material properties and cement mix design parameters. In this study, we curated an extensive dataset comprising 1756 unique AAC mixtures to support robust ML-based modeling. Four distinct input variable schemes were devised to identify the optimal predictor set, and a comparative analysis was performed to evaluate their effectiveness. After this, we investigated the performance of several popular ML algorithms, including random forest (RF), adaptive boosting (AdaBoost), gradient boosting regression trees (GBRTs), and extreme gradient boosting (XGBoost). Among these, the XGBoost model consistently outperformed its counterparts. To further enhance the predictive accuracy of the XGBoost model, we applied four state-of-the-art optimization techniques: the Gray Wolf Optimizer (GWO), Whale Optimization Algorithm (WOA), beetle antennae search (BAS), and Bayesian optimization (BO). The optimized XGBoost model delivered superior performance, achieving a remarkable coefficient of determination (R2) of 0.99 on the training set and 0.94 across the entire dataset. Finally, we employed SHapely Additive exPlanations (SHAP) to imbue the optimized model with interpretability, enabling deeper insights into the complex relationships governing AAC formulations. Through the lens of ML, we highlight the benefits of the multi-faceted synergistic approach for AAC strength prediction, which combines careful input parameter selection, optimal hyperparameter tuning, and enhanced model interpretability. This integrated strategy improves both the robustness and scalability of the model, offering a clear and reliable prediction of AAC performance.
Application of X-Ray Computed Tomography to Identify Defects in Lost Wax Ceramic Moulds for Precision Casting of Turbine Blades
Authors: Żaba Krzysztof , Gracz Dawid , Trzepieciński Tomasz , Książek Marzanna , Sitek Ryszard , Tchórz Adam , Balcerzak Maciej , Wałach Daniel
Published: October 2024

This article presents the results of testing the suitability of X-ray computed tomography for the quality control of the casting moulds used for producing turbine blades. The research was focused on the analysis of cross-sectional images, spatial models and the porosity of moulds using a Phoenix L 450 microtomograph. The research material consisted of samples from three mixtures of ceramic materials and binders intended for producing casting moulds using the lost wax method. Various configurations of filling materials (Molochite and quartz flours) and binder (Remasol, Ludox PX 30 and hydrolysed ethyl silicate) mixtures were considered. X-ray computed tomography enabled the detection of a number of defects in the ceramic mass related to the distribution of mass components, porosity concentration and defects resulting from the specificity of the mould production. It was found that casting mould quality control on cross-sectional tomographic images is faster and as accurate as the analysis of three-dimensional models and allows for the detection of a whole range of ceramic defects, but the usefulness of the images is greatest only when the cross-sections are taken at an appropriate angle relative to the object being examined.
A Note on a Min–Max Method for a Singular Kirchhoff Problem of Fractional Type
Authors: Alsaedi Ramzi
Published: October 2024

In the present work, we study a fractional elliptic Kirchhoff-type problem that has a singular term. More precisely, we start by proving some properties related to the energy functional associated with the studied problem. Then, we use the variational method combined with the min–max method to prove that the energy functional reaches its global minimum. Finally, since the energy functional has a singularity, we use the implicit function theorem to show that the point where the minimum is reached is a weak solution for the main problem. To illustrate our main result, we give an example at the end of this paper.
Vascularised and Non-Vascularised Adipofascial Flap Applications in Tissue Trauma with Tendon Injury, Flap Viability and Tendon Healing a Hystological and Scintigraphical Rat Model Study
Authors: Yucens Mehmet , Aydemir Ahmet Nadir , Sengoz Tarık , Mete Gulcin Abban , Ök Nusret , Koç Mehmet Rauf , Demirkan Ahmet Fahir
Published: October 2024

Background and Objectives: Complex wounds in the hand and distal lower extremities pose challenges in reconstructive surgery, often involving critical structures like tendons. Tendon injuries, prevalent in such wounds, necessitate optimal repair methods for functional recovery. This study investigates the impact of vascularised and nonvascularised adipofascial tissue on tendon repair, focusing on early healing stages, mobilisation, and scintigraphic evaluation of flap vascularity. Materials and Methods: Wistar Albino rats were divided into groups undergoing primary tendon repair, vascularised adipofascial flap application, or nonvascularised flap application. Scintigraphic evaluation and histopathological assessment were performed to analyse healing processes. Results: Pedicle-free flaps support healing in tendon injuries without negatively affecting medium-term outcomes. Vascularised flaps exhibit faster healing. The scintigraphic analysis showed that the static measurements of the late phase were statistically significantly higher in the group with the non-vascularised adipofascial flap (p = 0.038). The mean perfusion reserve was higher in the vascularised pedicled adipofascial flap group than the non-vascularised adipofascial flap group. Scintigraphic analysis highlights the viability of pedicle-free flaps. Conclusions: Pedicle-free adipofascial flaps support the healing of the tendon without complicating the results, while vascularised flaps show accelerated healing. These findings provide valuable insights into optimising tendon repair strategies using adipofascial flaps, with implications for enhancing functional recovery in complex wounds.
The Preparation of Future Statistically Oriented Physicians: A Single-Center Experience in Saudi Arabia
Authors: Sayed Anwar A.
Published: October 2024

Background and Objectives: Statistics are of paramount significance to physicians as they allow them to critically interpret the medical literature and to contribute to it. However, teaching statistics to medical students and physicians, as well as learning statistics, is nothing short of difficult and anxiety-inducing to a great extent. Materials and Methods: In this study, an example of a novel approach to teaching statistics to medical students is introduced at a single college of medicine in Saudi Arabia. In this retrospective report, a new approach that has been developed and delivered to students is described. Results: The approach, referred to as the personal experience pathway, is part of a major curriculum change to the MBBS program. The track presents statistics to students as a tool, rather than a subject, that students will need to interpret results, either present in the literature or those of the research projects they are conducting. The outcome of this process has been assessed through measuring students’ scholarly output through student self-reporting and has been followed up over four student cohorts graduating between the years 2019 and 2022. The approach has successfully equipped students with a solid foundation of statistical understanding that has allowed them to publish in peer-reviewed journals. Such scholarly output has increased significantly over the last two years. Conclusions: The current study presents a framework through which the detailed curriculum plan could be applied to other medical schools, nationally and internationally, which will better prepare future statistically oriented physicians.
Early-Stage and Locally Advanced Cervical Cancer during Pregnancy: Clinical Presentation, Diagnosis and Treatment
Authors: Mruzek Hanna , Kacperczyk-Bartnik Joanna , Dańska-Bidzińska Anna , Ciebiera Michał , Grabowska-Derlatka Laretta , Derlatka Paweł
Published: October 2024

In this comprehensive review supported by clinical examples, the authors explore the topic of cervical cancer in pregnancy, with emphasis on potential pre-cancer progression, the possibility of coexisting preinvasive and invasive disease, and neoadjuvant chemotherapy. This manuscript addresses the challenges of managing cervical cancer in pregnant women with a pregnancy-preserving approach, including the importance of screening, the timing of surgery, and the impact of pregnancy on the course of the disease. The first case study illustrates the potential for a benign cervical lesion to transform into a malignant one during pregnancy and the possible coexistence of preinvasive lesions together with early-stage cervical cancer. It also questions the rationale behind the non-treatment of pregnant patients initially diagnosed with CIN 2/3 during pregnancy. The second presented clinical example shows the histologically confirmed response to neoadjuvant chemotherapy, resulting in a radiologically diagnosed FIGO stage IIA1 being downgraded to adenocarcinoma in situ in the histology report after surgery performed six weeks postpartum. The treatment of cervical cancer, which is becoming increasingly prevalent among pregnant women, and the necessity for an individualized diagnostic and therapeutic approach represent significant challenges for contemporary medicine. Discrepancies in therapeutic options proposed among centers within the same region lead to the conclusion that there is a need for centralization and unification of evidence-based management in referral centers with both high-level oncological and perinatal care.
Part-Scale Thermomechanical and Grain Structure Modeling for Additive Manufacturing: Status and Perspectives
Authors: Zhang Yancheng , Guillemot Gildas , Camus Théophile , Senninger Oriane , Bellet Michel , Gandin Charles-André
Published: October 2024

Thermomechanical modeling of additively manufactured parts made by laser powder bed fusion aims to control stresses and distortions built during processing. This is, by nature, a multiscale metallurgical and mechanical problem, notably due to the strong texture of the grain structure that results from the process and may locally dictate the thermomechanical behavior law. Similarly, stresses and distortions are directly influenced by the heat transfer process at the system scale, including the consequences of the link between the part and the substrate and the weaker interactions with the powder bed and the gas environment. To achieve relevant modeling, we first demonstrate capabilities to assess at part scale, both i- the prediction of the grain structure and ii- the thermomechanical analyses. A discussion follows that summarizes the foreseen directions to achieve coupling and/or chaining between grain structure simulations and mechanical analyses at part scale.
Wetting Behaviors of Al-Si-Cu-Mg-Zn Brazing Materials on 5083 Aluminum Alloy
Authors: Guo Wei , Zhuo Yuechao , Zhao Yonglin , Li Han , Han Bingyuan
Published: October 2024

The wetting behaviors of Al-Si-Cu-Mg-Zn brazing materials on 5083 aluminum alloy substrate were investigated through changing the proportion of Mg from 0 to 2 wt.%. The experimental results showed that the welding process goes through the three following stages: slow spreading, fast spreading, and stabilizing. The wettability of the brazing material was improved effectively, and the porosity of the interfacial layer was reduced, with the addition of Mg. With Mg content at 1 wt.%, the wetting diameter reached a maximum value of 20.46 mm. The reaction mechanism of the wetted interfacial layer between the brazing material and substrate alloy was illustrated with dynamic data, provided through experimentation and simulated thermodynamic calculation, and showed that the wetting behavior of the resultant Al-7.5Si-15Cu-1Mg-5Zn brazing material was dominated primarily by a diffusion reaction from elemental magnesium.
Optimized Driving Scheme for Three-Color Electrophoretic Displays Based on the Elimination of Red Ghost Images
Authors: Jiang Mouhua , Yi Zichuan , Wang Jiashuai , Li Feng , Lai Boyuan , Li Liangyu , Wang Li , Liu Liming , Chi Feng , Zhou Guofu
Published: October 2024

Three-color electrophoretic display (EPD) is emerging as a display technology due to its extremely low energy consumption and excellent reflective properties. However, in the process of black and white color image transition, due to the different driving characteristics of red particles, the particles within the three-color EPD cannot be ideally driven to the target position, resulting in the appearance of a red ghost image. For this reason, this study utilized the COMSOL 5.6 finite element simulation method to construct a three-dimensional simulation model to explore the motion characteristics of electrophoretic particles, and then proposed a new driving scheme. The driving scheme aimed to drive red particles to the target position and eliminate the red ghost image by optimizing the pixel erasing stage and employing a high-frequency oscillating voltage. The final experimental results showed that after adopting the proposed driving scheme, the red ghost image was reduced by 8.57% and the brightness of the white color image was increased by 17.50%. This method effectively improved the display performance of three-color EPDs and contributed to the better application of three-color EPDs in the field of high-reflectivity and high-quality display.
Air Leakages at Microvalves: Pressure Decay Measurements and Extended Continuum Modelling of Knudsen Flows
Authors: Anheuer Daniel , Schwarz Johannes , Debera Patrick , Heinrich Klaus , Kutter Christoph , Richter Martin
Published: October 2024

To improve the performance of valves in relation to the leakage rate, a comprehensive evaluation of the valve characteristics and behavior during pressure exposure is important. Often, these low gas flow rates below 0.1 cm3/min cannot be accurately measured with conventional flow sensors. This paper presents a small and low-cost test rig for measuring gas leakage rates accurately, even far below 0.1 cm3/min, with the pressure decay method. These leakage flows are substantiated with a flow model, where we demonstrate the feasibility of modeling those gas flows with an extended Navier–Stokes framework to obtain more accurate theoretical predictions. As expected, the comparison to the experimental results proves that the classical Navier–Stokes system is unsuitable for modeling Knudsen flows. Hence, self-diffusion of gas, a wall-slip boundary condition, and an effective mean free path model were introduced in a physically evident manner. In terms of the calculated mass flow, while self-diffusion and slip boundary conditions explain deviations from the classical Navier–Stokes equation for Knudsen numbers already smaller than 1, the effective mean free path model has an effect, especially when Kn > 1. For simplified conditions, an analytical solution was presented and compared to the results of an OpenFOAM CFD-solver for flow rates through more complex gap-flow geometries of the flap valve. Hereby, acceptable deviations between 10% and 20% were observed. A comparison with measurement results was carried out. The reproducibility of the measurement method was verified by comparing multiple measurements of one silicon microvalve sample to a state-of-the-art flow sensor. Three geometrically similar passive silicon microvalves were measured with air overpressure decreasing from 15 kPa relative to atmospheric pressure. Maximum gas volume flowing in a blocking direction of 1–26 µL/min with high reproducibility and marginal noise were observed.
Plastic Polymers and Antibiotic Resistance in an Antarctic Environment (Ross Sea): Are We Revealing the Tip of an Iceberg?
Authors: Caruso Gabriella , Azzaro Maurizio , Dell’Acqua Ombretta , Papale Maria , Lo Giudice Angelina , Laganà Pasqualina
Published: October 2024

Microbial colonization of plastic polymers in Antarctic environments is an under-investigated issue. While several studies are documenting the spread of plastic pollution in the Ross Sea, whether the formation of a plastisphere (namely the complex microbial assemblage colonizing plastics) may favor the spread of antibiotic-resistant bacteria (ARB) in this marine environment is unknown yet. A colonization experiment was performed in this ecosystem, aiming at exploring the potential role of plastic polymers as a reservoir of antibiotic resistance. To this end, the biofilm-producing activity and the antibiotic susceptibility profiles of bacterial strains isolated from biofilms colonizing submerged polyvinylchloride and polyethylene panels were screened. The colonization experiment was carried out at two different sites of the Ross Sea, namely Road Bay and Tethys Bay. Most of bacterial isolates were able to produce biofilm; several multidrug resistances were detected in the bacterial members of biofilms associated to PVC and PE (also named as the plastisphere), as well as in the bacterial strains isolated from the surrounding water. The lowest percentage of ARB was found in the PE-associated plastisphere from the not-impacted (control) Punta Stocchino station, whereas the highest one was detected in the PVC-associated plastisphere from the Tethys Bay station. However, no selective enrichment of ARB in relation to the study sites or to either type of plastic material was observed, suggesting that resistance to antibiotics was a generalized widespread phenomenon. Resistance against to all the three classes of antibiotics assayed in this study (i.e., cell wall antibiotics, nucleic acids, and protein synthesis inhibitors) was observed. The high percentage of bacterial isolates showing resistance in remote environments like Antarctic ones, suffering increasing anthropic pressure, points out an emerging threat with a potential pathogenic risk that needs further deepening studies.
The Impact of Winter Cover Crops on Soil Nematode Communities and Food Web Stability in Corn and Soybean Cultivation
Authors: Akanwari Jerry , Islam Md , Sultana Tahera
Published: October 2024

There is increasing adoption of winter cover crops (WCCs) in corn and soybean production in Canada, primarily to reduce erosion and increase soil organic matter content. WCCs have the potential to influence nematode communities by increasing free-living nematodes and decreasing plant-parasitic nematodes or vice versa. However, the mechanism by which WCCs change nematode community assemblages still remains a key question in soil food web ecology. We tested the hypothesis that the long-term use of rye (Secale cereale), barley (Hordeum vulgare) and oat (Avena sativa) as monocultures or mixtures promotes nematode communities and improves overall soil health conditions compared to winter fallow. The results from this study revealed that the use of WCCs generally promoted a higher abundance and diversity of nematode communities, whereas plant parasitic nematodes were the most abundant in winter fallow. Moreover, the mixtures of WCCs had more similar nematode communities compared to rye alone and winter fallow. The structure and enrichment indices were higher with WCCs, indicating higher nutrient cycling and soil suppressiveness, which are signs of healthy soil conditions. Furthermore, WCCs significantly reduced the populations of root lesion nematode Pratylenchus, although their numbers recovered and increased during the main crop stages. Additionally, mixtures of WCCs promoted the highest abundance of the stunt nematode Tylenchorhynchus, whereas winter fallow had a higher abundance of the spiral nematode Helicotylenchus during the fallow period and the main crop stages. The results show that the long-term use of cover crops can have a positive impact on nematode communities and the soil food web, but these changes depend on the type of WCCs and how they are used.