bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of the Influence of Fused Deposition Modeling 3D Printing Process Parameters on Tensile Properties of Polylactic Acid Parts Using the Taguchi Method
Authors: Megersa Getu Koro , Sitek Wojciech , Nowak Agnieszka J. , Tomašić Neven
Published: December 2024

Despite Fused Deposition Modeling (FDM) being an economical 3D printing method known for its material versatility and ease of use, the mechanical performance of FDM-produced components is significantly influenced by process parameter settings. This study investigated the effects of the layer thickness, raster angle, build orientation, and extrusion temperature on the ultimate tensile strength (UTS) and elastic modulus of Polylactic Acid (PLA) specimens using Taguchi methods, with significance analyzed through analysis of variance (ANOVA). The results indicated that the build orientation is the primary factor affecting both the UTS and elastic modulus, with a flat orientation yielding the best performance. ANOVA showed that the build orientation, raster angle, and extrusion temperature significantly influence the UTS, with the build orientation contributing 98.16%. For the elastic modulus, the build orientation and raster angle were significant, contributing 94.83% and 1.76%, respectively. The optimal parameters were a 0.16 mm layer thickness, flat build orientation, 30°/−60° raster angle, and 200 °C extrusion temperature, resulting in predicted UTS and elastic modulus values with error percentages of 4.33% and 2.74%, respectively, compared to experimental values. The regression model demonstrated high predictive accuracy, with R-squared values of 99.71% for the UTS and 99.52% for the elastic modulus.
Water Absorption of Underwater Products by Additive Manufacturing
Authors: Pino Andrea , Ibáñez-Felip Iván , Vidal Rosario
Published: December 2024

Rapid prototyping techniques offer significant advantages in terms of fabrication speed, accessibility, and low cost. This study explores the use of low-cost stereolithographic resins to produce prototypes intended for underwater conditions. The objective is to evaluate the feasibility of different low-cost resin brands by identifying their water absorption percentage and their response in terms of appearance and deformation after prolonged exposure to an underwater environment. Through three different tests, the suitability of the resins and possible coatings is evaluated, allowing for obtaining data not disclosed by commercial manufacturers and indicating that there are low-cost brands that offer water absorption levels suitable for underwater use. The coefficients for water absorption at saturation begin at 3.3% in saltwater and increase for chlorinated water. Additionally, significant insights are gained regarding the use of coatings. It is found that coatings commonly applied to filament-printed prototypes are generally less suitable for parts produced through stereolithography intended for underwater applications. The most effective strategy is to avoid using coatings altogether.
A Numerical Study of Topography and Roughness of Sloped Surfaces Using Process Simulation Data for Laser Powder Bed Fusion
Authors: Aydogan Beytullah , Chou Kevin
Published: December 2024

The simulation of additive manufacturing has become a prominent research area in the past decade. Process physics simulations are employed to replicate laser powder bed fusion (L-PBF) manufacturing processes, aiming to predict potential issues through simulated data. This study focuses on calculating surface roughness by utilizing 3D surface topology extracted from simulated data, as surface roughness significantly influences part quality. Accurately predicting surface roughness using a simulation remains a persistent challenge. To address this challenge, the L-PBF technique with two different cases (pre- and post-contouring) was simulated using two-step process physics simulations. The discrete element method was utilized to simulate powder spreading, followed by the Flow-3D melting simulation. Ten layers were simulated at three different linear energy density (LED) combinations for both cases, with samples positioned at a 30-degree angle to accommodate upskin and downskin effects. Furthermore, a three-dimensional representation of the melted region for each layer was generated using the thermal gradient output from the simulated data. All generated 3D layers were stacked and merged to consolidate a 3D representation of the overall sample. The surfaces (upskin, downskin, and side skins) were extracted from this merged sample. Subsequently, these surfaces were analyzed, and surface roughness (Sa values) was calculated using MATLAB. The obtained values were then compared with experimental results. The downskin surface roughness results from the simulation were found to be within the range of the experimental results. This alignment is attributed to the fact that the physics simulation primarily focuses on melt pool depth and width. These promising findings indicate the potential for accurately predicting surface roughness through simulation.
Improved Surface Quality and Microstructure Regulation in High Power Fiber Laser Cutting of Stainless Steel Grid Plates
Authors: Xu Linjiang , Wang Chunming , Yan Fei , Hu Zhuangxi , Zhang Wei
Published: December 2024

In order to disintegrate nuclear fuel rods in the grid connection structure, a 10 kW fiber laser was used to cut a stainless steel simulation component with four layers of 3 mm thick plates and 12 mm gaps. The slit width is regarded as an important indicator to evaluate the cutting quality of the four-layer stainless steel plate. The results showed that good laser cutting quality can be successfully achieved under the proper process parameters. The widths of the cut seams of the four layers of grating after cutting were 1.25, 1.65, 1.80, and 1.92 mm. As the auxiliary gas pressure decreased layer by layer, the metal melting pool for the first two plates was mainly destroyed by the auxiliary gas. The cutting quality was good, and the slit area was mainly austenite with the presence of some ferrite. The third- and fourth-layer plates almost had no gas flow to assist blowing off, so the cut surface was an uneven melting pit, the cutting quality was poor, and the cut seam area ferrite content was higher than the upper plate cut seam area. At the same time, due to the lack of airflow cooling of the bottom plate, high laser energy, and long heating time, grain coarsening occurred, while grain deformation and a large number of dislocations existed. It can provide process support and technical guidance for the disintegration of nuclear fuel rods.
Enhanced Interfacial Properties of Carbon Fiber/Polymerization of Monomers Reactants Method Polyimide Composite by Polyimide Sizing
Authors: Huang Chengyu , Sun Jinsong , Liu Zhiwei , Li Bo , Sun Mingchen , Liu Hansong , Zhao Yan , Zhang Peng , Bao Jianwen
Published: December 2024

Carbon fiber (CF)-reinforced polyimide (PI) resin matrix composites have great application potential in areas such as rail transport, medical devices, and aerospace due to their excellent thermal stability, dielectric properties, solvent resistance, and mechanical properties. However, the epoxy sizing agent used for traditional carbon fiber cannot withstand the processing temperature of polyimide resin, of up to 350 °C, resulting in the formation of pores or defects at the interface between the fiber and the resin matrix, leading to the degradation of the overall composite properties. To overcome this problem, in this study, a low-molecular-weight thermosetting polyimide sizing agent was prepared and the processability of the sized carbon fiber was optimized by a thermoplastic polyimide. Compared with the unsized carbon fiber polyimide composites, the interfacial properties of the composites after the polyimide sizing treatment were significantly improved, with the interfacial shear strength (IFSS) increasing from 82.08 MPa to 136.27 MPa, the interlaminar shear strength (ILSS) increasing from 103.7 to 124.9 MPa, and the bending strength increasing from 2262.2 MPa to 2562.1 MPa. The sizing agent acts as a bridge between the carbon fiber and polyimide resin, with anchorage and bonding at the interface between the fiber and resin, which are beneficial for enhancing the interface performance of composites.
Rectangular Improvement Method for Plan View Pattern of Plates During the Angular Rolling Process
Authors: He Chunyu , Luo Junyi , Xu Zhipeng , Wang Zhiqiang , Zhao Zhong , Wu Zhiqiang , Jiao Zhijie
Published: December 2024

The effect of the angular rolling process on the plan view pattern of a plate was studied, and the rectangular influencing factors and improvement methods for this process were proposed in this paper. DEFORM (v11.0) finite element software was used to simulate the processes of conventional rolling and angular rolling, and the degree of rectangularity of plates under different rolling process conditions was compared. A formula to characterize the degree of rectangularity of plates was established; the closer this value is to one, the better the degree of rectangularity. Considering the actual rolling process conditions, the range of theoretically calculated rectangular rotation angles was extended to obtain the optimum rectangular rotation angle using the finite element simulation method. In the two-pass angular rolling process, the optimal rectangular angle of the second pass was 14.275° when the first pass was 15°. The optimal rectangular angle of the plate was 19.008° when the first pass’ angle was 20°. Two-pass angular rolling is different to four-pass rolling, and the simulation results showed that J 15° 4 (1.0012) was less than J 15° 2 (1.0015) and J 20° 4 (1.0034) was less than J 20° 2 (1.0055). The rectangularity degree of the four-pass process was better than the two-pass process. Angular rolling experiments were carried out, and the actual data show that the characteristic rectangular value of the rolled piece was 1.003 during the four-pass process and 1.014 during the two-pass process. This verified that separating the one-group two-pass angular rolling process from the one-group four-pass angular rolling process can improve the rectangular degree of the rolled plate, thereby increasing the yield rate. This provides a theoretical basis for industrial applications.
A Container for Storing and Transporting Bulk Material Samples
Authors: Suchorab Zbigniew , Olszewska-Pastuszak Dagmara , Tabiś Krzysztof , Pluta Kamil
Published: December 2024

This article presents problems related to the storage of building material samples and discusses the related requirements and standards. Solutions for containers to store material samples were proposed and tests were performed in accordance with the EN ISO 12570 standard to demonstrate that all the water that may have condensed during the samples’ transport in the self-designed, closed container evaporates from the lid when unscrewed and placed under the container during the drying process. The aim of this study was to test the tightness of self-designed containers for transporting bulk samples. The drying efficiency at elevated temperatures in moisture tests for bulk material containers was determined and, finally, the influence of ambient conditions on a sample placed in a container for bulk material transport was estimated. The results confirmed that the designed container is vapour-tight and allows the collected material to be protected against evaporation during transport from the sampling site to the laboratory. Under extreme transport conditions, the water contained in the sample in a closed container partially evaporates from the material and condenses on the lid but this is taken into account when balancing the moisture of samples in the laboratory and does not falsify the readouts.
Deep Learning with Convolutional Neural Networks: A Compact Holistic Tutorial with Focus on Supervised Regression
Authors: Gonzalez Tejeda Yansel , Mayer Helmut A.
Published: December 2024

In this tutorial, we present a compact and holistic discussion of Deep Learning with a focus on Convolutional Neural Networks (CNNs) and supervised regression. While there are numerous books and articles on the individual topics we cover, comprehensive and detailed tutorials that address deep learning from a foundational yet rigorous and accessible perspective are rare. Most resources on CNNs are either too advanced, focusing on cutting-edge architectures, or too narrow, addressing only specific applications like image classification. This tutorial not only summarizes the most relevant concepts but also provides an in-depth exploration of each, offering a complete yet agile set of ideas. Moreover, we highlight the powerful synergy between learning theory, statistics, and machine learning, which together underpin the deep learning and CNN frameworks. We aim for this tutorial to serve as an optimal resource for students, professors, and anyone interested in understanding the foundations of deep learning.
Parameter-Efficient Fine-Tuning of Large Pretrained Models for Instance Segmentation Tasks
Authors: Abou Baker Nermeen , Rohrschneider David , Handmann Uwe
Published: December 2024

Research and applications in artificial intelligence have recently shifted with the rise of large pretrained models, which deliver state-of-the-art results across numerous tasks. However, the substantial increase in parameters introduces a need for parameter-efficient training strategies. Despite significant advancements, limited research has explored parameter-efficient fine-tuning (PEFT) methods in the context of transformer-based models for instance segmentation. Addressing this gap, this study investigates the effectiveness of PEFT methods, specifically adapters and Low-Rank Adaptation (LoRA), applied to two models across four benchmark datasets. Integrating sequentially arranged adapter modules and applying LoRA to deformable attention—explored here for the first time—achieves competitive performance while fine-tuning only about 1–6% of model parameters, a marked improvement over the 40–55% required in traditional fine-tuning. Key findings indicate that using 2–3 adapters per transformer block offers an optimal balance of performance and efficiency. Furthermore, LoRA, exhibits strong parameter efficiency when applied to deformable attention, and in certain cases surpasses adapter configurations. These results show that the impact of PEFT techniques varies based on dataset complexity and model architecture, underscoring the importance of context-specific tuning. Overall, this work demonstrates the potential of PEFT to enable scalable, customizable, and computationally efficient transfer learning for instance segmentation tasks.
The Continuity and Convexity of a Nonlinear Scalarization Function with Applications in Set Optimization Problems Involving a Partial Order Relation
Authors: Zhang Zi-Ru , Xu Yang-Dong
Published: December 2024

In this paper, we deal with the properties and applications of a nonlinear scalarization function for sets by using the Minkowski difference. Under some suitable assumptions, the continuity and convexity concerned with the nonlinear scalarization function for sets are presented. As applications, the path connectedness of the solution sets to set optimization problems and the continuity of the solution mappings of parametric set optimization problems are established. The results achieved do not impose the monotonicity of the set-valued objective mapping, which are obviously different from the related ones in the literature.
Robot Variable Impedance Control and Generalizing from Human–Robot Interaction Demonstrations
Authors: Zhong Feifei , Hu Lingyan , Chen Yingli
Published: December 2024

The purpose of this study was to ensure the compliance and safety of a robot’s movements during interactions with the external environment. This paper proposes a control strategy for learning variable impedance characteristics from multiple sets of demonstration trajectories. This strategy can adapt to the control of different joints by adjusting the parameters of the variable impedance control policy. Firstly, multiple sets of demonstration trajectories are aligned on the time axis using Dynamic Time Warping. Subsequently, the variance obtained through Gaussian Mixture Regression and a variable impedance strategy based on an improved Softplus function are employed to represent the variance as the variable impedance characteristic of the robotic arm, thereby enabling variable impedance control for the robotic arm. The experiments conducted on a self-designed robotic arm demonstrate that, compared to other variable impedance methods, the motion accuracy of the trajectories of joints 1 to 4 improved by 57.23%, 3.66%, 5.36%, and 20.16%, respectively. Additionally, a stiffness-variable segmented generalization method based on Dynamic Movement Primitive is proposed to achieve variable impedance control in various task environments. This strategy fulfills the requirements for compliance and safety during robot interactions.
Spontaneous Resolution of an Aggressive Direct Carotid Cavernous Fistula Following Partial Transvenous Embolization Treatment: A Case Report and Review of Literatures
Authors: Liao Wen-Jui , Hsiao Chun-Yuan , Chen Chin-Hsiu , Tseng Yuan-Yun , Yang Tao-Chieh
Published: December 2024

Traumatic direct type carotid cavernous fistula (CCF) is an acquired arteriovenous shunt between the carotid artery and the cavernous sinus post severe craniofacial trauma or iatrogenic injury. We reported a 46-year-old woman who had developed a traumatic direct type CCF after severe head trauma with a skull base fracture and brain contusion hemorrhage. The clinical manifestations of the patient included pulsatile exophthalmos, proptosis, bruits, chemosis, and a decline in consciousness. Magnetic resonance imaging (MRI) revealed engorgement of the right superior ophthalmic vein (SOV), perifocal cerebral edema in the right frontal–temporal cortex, right basal ganglia, and brain stem. Digital subtraction angiography (DSA) disclosed a direct type high-flow CCF with an aggressive cortical venous reflux drainage pattern, which was attributed to Barrow type A and Thomas classification type 5. After partial treatment by transvenous coil embolization for the CCF, the residual high-flow fistula with aggressive venous drainage had an unusual rapid spontaneous resolution in a brief period. Therefore, it is strongly recommended to meticulously monitor the clinical conditions of patients and perform brain MRI and DSA at short intervals to determine the treatment strategy for residual CCF after partial endovascular treatment.
Advancing Molecular Spectroscopy Efficiency with Extensive Parallelism
Authors: Li Jiaqi , Fernandez Rodrigo , Gutierrez Bernardo , Pedersen Jan , Zhou Yan
Published: December 2024

Molecular spectroscopy, with a legacy spanning over a century, has profoundly enriched our understanding of the microscopic world, driving major advancements across science and engineering. Over time, this field has steadily advanced, incorporating innovations such as lasers and digital computers to reach new levels of precision and sensitivity. Over the past decade, the integration of high-speed embedded electronic systems and advanced light sources has ushered molecular spectroscopy into a new era, characterized by extensive parallelism and enhanced sensitivity. This review delves into two pioneering technologies that embody recent advancements in molecular spectroscopy: Chirped-Pulse Fourier Transform Microwave (CP-FTMW) spectroscopy and optical frequency comb (OFC) spectroscopy. We provide an overview of the fundamental principles behind these methods, examine their most impactful applications across diverse fields, and discuss their potential to drive future developments in molecular spectroscopy. By highlighting these technologies, we aim to underscore the transformative impact of integrating high-speed digital electronics and advanced light sources with molecular spectroscopy, enabling extensive parallelism and paving the way for groundbreaking discoveries and innovations in this rapidly evolving field.
Bacterial Microbiota of the Brown Dog Tick (Rhipicephalus sanguineus), a Broad Starting Point to Establish Potential Pathogens in Northern Mexico
Authors: García-De la Peña Cristina , Zamudio-López Annely , Barraza-Guerrero Sergio I. , Martínez-Aranda Ernesto , De la Cruz-Ramos Josué M. , Acosta-Ayala Anehlvy , Siller-Rodríguez Quetzaly K. , Torres-Delgado María G. , Ávila-Rodríguez Verónica , Vásquez-Arroyo Jesús , Valenzuela-Núñez Luis M. , Herrera-Salazar Juan Carlos
Published: December 2024

Ticks are important vectors of pathogenic bacteria that cause diseases in both humans and animals. Analysis of tick microbiota via massive sequencing allows rapid and comprehensive identification of almost all bacteria inhabiting ticks. This has improved the detection of emerging pathogens and has helped define their relationship with public health. In Mexico, the brown dog tick (Rhipicephalus sanguineus sensu lato) is a public health problem, especially in northeast Durango. In the present study, the bacterial microbiota of this tick was determined using third-generation massive sequencing (PacBio, V1–V9 region of the 16S rRNA gene); bacteria with pathogenic potential that are transmitted by salivation and those that can be transmitted by accidental regurgitation of the parasite were also identified. In 2024, 60 dogs were searched for unfed ticks; then, 15 groups of female ticks and 15 groups of male ticks were formed, with each group consisting of 30 individuals. DNA was extracted from each tick pool, and the complete 16S rRNA gene was amplified (PacBio). Bioinformatics analysis was performed in QIIME2 (Quantitative Insights into Microbial Ecology) to obtain amplicon sequence variants (ASVs). Alpha and beta diversity metrics, as well as statistical analyses, were performed to test for differences between the microbiota of females and males. The bacterial taxa were classified into 21 phyla, 24 classes, 81 orders, 137 families, 339 genera, and 565 species. The male microbiota presented a significantly greater number of ASVs and a greater phylogenetic diversity index (FaithPD). Additionally, the unweighted UniFrac metric was significantly different between the sexes. The endosymbiont Coxiella mudrowiae was significantly more abundant in females, and Ehrlichia canis was more abundant in males. The pathogens E. canis and Anaplasma platys (transmitted by salivation) were detected, as well as 75 species of potential pathogens recorded in this tick that could enter the host in case of accidental regurgitation of the parasite (e.g., Staphylococcus, Streptococcus, Acinetobacter, Corynebacterium, Proteus, Clostridum, Klebsiella, Bacillus, Escherichia, Fusobacterium, and Pasteurella). It is necessary to continue analyzing the microbiota of ticks through massive sequencing for the benefit of public health and to establish new alternatives for controlling these parasites.
Disruption of Biofilm Formation by Dead Sea Soil Extracts: A Novel Approach Against Diabetic Foot Wound Isolates
Authors: Zubair Mohammad , Fatima Farha , Rahman Sumbul , Alrasheed Tariq , Alatawy Roba , Mesaik M. Ahmed
Published: December 2024

Bacterial biofilms are closely associated with the rising threat of antimicrobial resistance, which is becoming a global concern. Recently, there has been increased interest in natural extracts as potential antimicrobial agents. One such extract is Dead Sea mud. While there is some evidence of its antimicrobial properties, it has not been extensively studied. Therefore, we designed a study to evaluate the potential of Dead Sea soil as an antimicrobial agent. For this purpose, three bacterial species (Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus) were isolated from the ulcerated foot of a patient in a hospital in Tabuk. P. aeruginosa exhibited significant antibiotic resistance, particularly to Levofloxacin (90%) and Tobramycin (80%), while S. aureus showed 70% resistance to Levofloxacin but no vancomycin resistance. Biofilm activity varied among bacterial strains, with P. aeruginosa showing 30% strong biofilm production. MIC values indicated resistance levels, with P. aeruginosa strain PA8 having the highest MIC at 650 µL/mL. All strains showed significant differences in exopolysaccharide (EPS) production at 0.25 × MIC (p ≤ 0.05) and 0.5 × MIC (p ≤ 0.005). Similarly, alginate production was significantly reduced at 0.25 × MIC (p ≤ 0.05), with even greater inhibition at 0.5 × MIC for combinations such as EC7 + SA5 (p ≤ 0.001). Hydrophobicity significantly changed at 0.25 × MIC (p ≤ 0.05), and combinations revealed highly significant reductions at 0.5 × MIC (p ≤ 0.001). Additionally, significant differences in outer membrane disruption were observed (p ≤ 0.05) with greater effects at 0.5 × MIC (p ≤ 0.005). Swarming motility was notably reduced for SA5 at 0.25 × MIC (p ≤ 0.05) and for PA2 at 0.5 × MIC (p ≤ 0.001). Chitinase activity showed greater reductions at 0.5 × MIC, with EC7 exhibiting the highest decrease. Lastly, sub-MIC concentrations enhanced reactive oxygen species (ROS) production, particularly for strains PA2 and SA5. Our results demonstrate the excellent potential of Dead Sea soil extract as an antimicrobial compound. Future studies should incorporate in vivo models to validate these findings clinically.
Bioinformatic Methodologies in Assessing Gut Microbiota
Authors: Fox James Douglas , Sims Austin , Ross Morgan , Bettag Jeffery , Wilder Alexandra , Natrop Dylan , Borsotti Alison , Kolli Sree , Mehta Shaurya , Verma Hema , Kurashima Kento , Manithody Chandrashekhara , Verma Arun , Jain Ajay
Published: December 2024

Bioinformatic methodologies play a crucial role in the assessment of gut microbiota, offering advanced tools for analyzing complex microbial communities. These methodologies involve high-throughput sequencing technologies, such as 16S rRNA gene sequencing and metagenomics, which generate vast amounts of data on microbial diversity and functional potential, as well as whole-genome sequencing, which, while being more costly, has a more expansive potential. Bioinformatics tools and algorithms process these data to identify microbial taxa and quantify and elucidate their roles within the microbiome. Advanced statistical and computational models further enable the identification of microbiota patterns associated with various diseases and health conditions. Overall, bioinformatic approaches are essential for deciphering the complexities of gut microbiota so that, in the future, we may be able to discover treatments and technologies aimed at restoring or optimizing the microbiome. The goal of this review is to describe the differences in methodology and utilization of 16S versus whole-genome sequencing to address the increased understanding of the role that the gut microbiome plays in human physiology and pathology.
In Vitro Activity of Ampicillin Plus Ceftriaxone Against Non-faecalis and Non-faecium Enterococcal Isolates With/Without VanC Phenotype: Clinical Implications for Infective Endocarditis
Authors: García-González Javier , Cañas María A. , Cuervo Guillermo , Hernández-Meneses Marta , Verdejo Miguel A. , Bodro Marta , Díez de los Ríos Javier , Gasch Oriol , Ribera Alba , Falces Carles , Perissinotti Andrés , Vidal Bárbara , Quintana Eduard , Moreno Asunción , Piquet Maria , Roca Ignasi , Fernández-Pittol Mariana , San José-Villar Sol M. , García-de-la-Mària Cristina , Miró José M. ,   the Hospital Clínic Endocarditis Study Group
Published: December 2024

(1) Background: Alternative antibiotics are needed to treat infective endocarditis (IE) caused by non-faecalis/non-faecium enterococci; we aimed to assess the in vitro activity of ampicillin plus ceftriaxone (AMP + CTR) against these enterococci and to describe its clinical efficacy in IE cases. (2) Methods: Time–kill curves with standard (ISI) and high (IHI) inocula were performed to test VanC isolates [3 E. casseliflavus (ECAS) and 1 E. gallinarum (EGALL)] and non-VanC isolates [1 E. durans (EDUR), 1 E. hirae (EHIR) and 1 E. raffinosus (ERAF)]. The narrative literature review of IE cases treated with AMP + CTR was analyzed alongside three study cases. Clinical outcomes were relapse and death. (3) Results: Ampicillin plus gentamicin (AMP + GEN) showed synergistic and bactericidal activity against most isolates. AMP + CTR was synergistic at ISI for EGALL, EDUR, and EHIR and bactericidal against EHIR. At IHI, indifferent activity was observed for all isolates. In IE cases treated with AMP + CTR, it was only effective for EDUR and EHIR. Clinical information for EGALL IE is lacking. For IE caused by ECAS and ERAF, AMP + CTR seems suboptimal or ineffective, respectively. (4) AMP + CTR cannot be recommended for treating IE due to ECAS/ERAF. In contrast, this combination was effective in IE caused by EDUR/EHIR and could be recommended.
Extraction of Gold from Tailings Using Ethaline Deep Eutectic Solvent
Authors: Khuduwe Marema Jack , Shemi Alan , Ndlovu Sehliselo
Published: December 2024

For over a century, cyanidation has been a highly effective method for extracting gold from gold-bearing sources. However, due to environmental, health, and safety concerns associated with this process, considerable efforts have been devoted to exploring the use of alternative, less toxic, and environmentally friendly reagents. In this study, a comparative cyanide and ethaline deep eutectic solvent (DES) leaching study of gold from the Witwatersrand gold tailings was undertaken. A Statistical Design of Experiments (DOE) was used for the screening and optimization of significant process factors to achieve optimal gold extraction. The factors investigated include the reagent concentration, leaching time, pulp density, and solution temperature. The subsequent gold recovery from leach solutions was undertaken using activated carbon (AC). Mineralogical analysis by X–ray diffraction (XRD) showed that the tailings consisted of quartz (72.13%), muscovite (7.49%), chlorite (2.65%), pyrophyllite (1.50%), clinochlore (1.30%), and other trace minerals. Mineral liberation analysis (MLA) employing the Sparse Liberation–Dual Zoom (SPL-DZ) method showed that gold was associated with iron oxides (Fe2O3, Fe3O4). Fire assay analysis (FAA) showed that the bulk tailings had a grade of 0.32 g/t Au. Ethaline was found to be the most efficient reagent, achieving up to 71.9% gold extraction, thereby exceeding the 46.9% gold extraction obtained via the cyanidation process. Moreover, gold recovery using AC from ethaline leach solution was 75%. The high gold extraction from tailings using ethaline suggests a potentially feasible alternative to the traditional cyanidation process, particularly for the processing of gold locked in iron oxide phases, offering the advantages of low toxicity, cost-effectiveness, and ease of preparation.
Tungsten Skarn Quantitative Mineral Resource Assessment and Gold, Rare Earth Elements, Graphite, and Uranium Qualitative Assessments of the Kuldjuktau and Auminzatau Ranges, in the Central Kyzylkum Region, Uzbekistan
Authors: Coyan Joshua , Solano Federico , Taylor Cliff , Finn Carol , Smith Steven , Holm-Denoma Christopher , Pianowski Laura , Crocker Kelsey , Mirkamalov Rustam , Divaev Fareed , Baratov Abdulla , Khakimov Botir , Azimov Jurabek , Goipov Akram , Avulov Jamshid , Akhmadov Shokir , Inatov Nurbek , Janiev Xurshid , Dulabova Nafisa
Published: December 2024

A new quantitative mineral resource assessment for tungsten skarn was conducted for the Auminzatau and Kuldjuktau mountain ranges in Central Uzbekistan, along with qualitative assessments of orogenic gold, rare earth elements (REEs), amorphous graphite, and uranium. By integrating a variety of geological, geochemical, geophysical, and remote sensing data sets, estimates of undiscovered tungsten skarn deposits in permissive tracts are combined with grade and tonnage distributions of known deposits to generate probabilistic estimates of undiscovered resources. Undiscovered deposits in Auminzatau are estimated to contain median resources of 98 thousand metric tons (kt) of WO3 with a 70 percent (%) probability of at least 28 kt and a 10% probability of at least 468 kt, of which 16 kt to 293 kt may be economic to extract. In Kuldjuktau, the undiscovered deposits are estimated to contain median resources of 27 kt of WO3 with a 60% probability of at least 12 kt and a 10% probability of at least 208 kt, of which 5 kt to 132 kt may be economic to extract. Our results suggest that the Auminzatau–Kuldjuktau Mountains area is highly prospective for additional discovery of significant Au and U resources and has low prospectivity for discovery of significant REE and graphite resources.
Analysis of Short-Range Ordering Effect on Tensile Deformation Behavior of Equiatomic High-Entropy Alloys TiNbZrV, TiNbZrTa and TiNbZrHf Based on Atomistic Simulations
Authors: Babicheva Rita I. , Semenov Aleksander S. , Izosimov Artem A. , Korznikova Elena A.
Published: December 2024

In the study, the combined molecular dynamics and Monte Carlo (MD/MC) simulation was used to investigate the short-range ordering effect on tensile deformation of bicrystals with grain boundaries (GBs) Σ3(11¯2)[110]. Three different equiatomic high-entropy alloys, namely, ZrTiNbV, ZrTiNbTa and ZrTiNbHf, were considered. The tensile loading at 300K was applied in the direction perpendicular to the GBs’ planes. The stress–strain response as well as the structure evolution of the alloys with initial random distribution of atoms were compared with results obtained for the corresponding materials relaxed during the MD/MC procedure. It was revealed that the distribution of atoms in the alloys significantly affects the deformation process. Ordered clusters of Nb atoms are able to suppress the dislocation sliding and twin formation increasing the yield strength of ZrTiNbV. On the contrary, in ZrTiNbTa, the twinning mechanism is dominant in the case of the ordered structure due to the absence of Nb clusters and the presence of areas enriched with Zr atoms, which ease nucleation of dislocations and twins. Since Hf decreases the stability of the body-centered cubic lattice, the main deformation mechanism of ZrTiNbHf is the stress-induced phase transition; however, Nb clusters inside grains of the relaxed alloy slightly delay this process.
Efficient Numerical Modeling of Oil-Immersed Transformers: Simplified Approaches to Conjugate Heat Transfer Simulation
Authors: Smolyanov Ivan , Shmakov Evgeniy
Published: December 2024

The development of digital twins for power transformers has become increasingly important to predict possible operating modes and reduce the likelihood of faults. The accuracy of these predictions relies heavily on the numerical models used, which must be both simple and computationally efficient. This work focuses on creating a simplified numerical model for a template oil-immersed power transformer (100 MVA, 230/69 KV). The study investigates how the number of elements and the strategies used to set up the mesh in the domain of interest influence the results, aiming to identify the key parameters that affect the outcomes. Furthermore, a significant effect of resolving thermal boundary layers on the accurate identification of hot spots is demonstrated. Two approaches to resolving thermal boundary layers are explored in this work. This study presents a comprehensive analysis of three numerical models for conjugate heat transfer simulations, each with distinct features and computational domain compositions. The results show that the addition of extra calculation domains leads to the emergence of new vortex structures, affecting the velocity profile at the channel inlet and altering the location of hot spots. This study provides valuable insights into the configuration and composition of calculated domains in numerical models of oil-immersed power transformers, essential for the accurate prediction of hot spot temperatures and ensuring reliable operation.
Non-Linear Control and Numerical Analysis Applied in a Non-Linear Model of Cutting Process Subject to Non-Ideal Excitations
Authors: Tusset Angelo M. , Cruz Jonierson A. , Balthazar Jose M. , Fuziki Maria E. K. , Lenzi Giane G.
Published: December 2024

This work presents a non-linear mathematical model of a machining system subjected to a non-ideal vibration source. Computer simulations have shown chaotic behavior for specific parameters of the proposed mathematical model. The chaotic behavior is proven using time histories, phase diagrams, bifurcation diagrams, and the Lyapunov exponent. Considering that cutting tool vibration in the machining process is one of the main problems of productivity and machining accuracy, the introduction of a magnetorheological damper was considered in the proposed model to reduce the vibration amplitudes of the cutting tool and suppress the chaotic behavior. Hysteresis was considered in the magnetorheological damper model and its application in the system as both a passive and active absorber. The active control strategy considered the application of two non-linear control signals: feedforward to maintain the vibration with a desired behavior and state feedback to drive the system to the desired behavior. The numerical results demonstrated that the proposed controls efficiently reduced the vibration amplitude by introducing the MR damper. Active control has proven effective in controlling the force of the MR damper by varying the electrical voltage applied to the damper coil.
Modeling the Bending of a Bi-Layer Cantilever with Shape Memory Controlled by Magnetic Field and Temperature
Authors: Stolbova Olga S. , Stolbov Oleg V.
Published: December 2024

This paper presents a model of the bending behavior of a bi-layer cantilever composed of titanium nickelide and a magnetoactive elastomer embedded with magnetically hard particles. The cantilever is initially subjected to an external magnetic field in its high-temperature state, followed by cooling to a low-temperature state before the magnetic field is removed. This sequence results in residual bending deformation. Basic relations describing the material behavior of titanium nickelide and the magnetoactive elastomer are presented. A variational formulation for the problem under consideration is written down. The problem is solved numerically using the finite element method. The influence of the applied magnetic field magnitude and the thickness of the titanium nickelide layer on the cantilever deflection magnitude is studied. The dependence of the residual cantilever deflection on the applied magnetic field is obtained. The possibility of this structure as a controllable gripping element for applications in robotics and micro-manipulation is demonstrated.
Mixed-Presence Collaboration with Wall-Sized Displays: Empirical Findings on the Benefits of Awareness Cues
Authors: Maquil Valérie , Coppens Adrien , Schwartz Lou , Anastasiou Dimitra
Published: December 2024

Collaborative decision-making increasingly involves wall-sized displays (WSDs), allowing teams to view, analyse and discuss large amounts of data. To enhance workspace awareness for mixed-presence meetings, previous work proposes digital cues to share gestures, gaze, or entire postures. While several isolated cues were proposed and demonstrated useful in different workspaces, it is unknown whether results from previous studies can be transferred to a mixed-presence WSD context and to what extend such cues can be used in a combined way. In this paper, we report on the results from a user study with 24 participants (six groups of four participants), testing a mixed-presence collaboration scenario on two different setups of connected WSDs: audio-video link only vs. full setup with seven complementary cues. Our results show that the version with cues enhances workspace awareness, user experience, team orientation and coordination, and leads teams to take more correct decisions.
Gain Saturation of Encapsulated CdTe-Ag Quantum Dot Composite in SiO2
Authors: Kim Minwoo , Antony Agna , Kim Inhong , Kim Minju , Kyhm Kwangseuk
Published: December 2024

Amplified spontaneous emission of CdTe and CdTe-Ag quantum dot composites were compared for increasing the optical stripe length, whereby optical gain coefficients for various emission wavelengths were obtained. In the case of CdTe-Ag nanoparticle composites, we observed that plasmonic coupling causes both optical enhancement and quenching at different wavelengths, where the amplified spontaneous emission intensity becomes enhanced at short wavelengths but suppressed at long wavelengths (>600 nm). To analyze the logistic stripe length dependence of amplified spontaneous emission intensity, we used a differential method to obtain the gain coefficient beyond the amplification range. This analysis enabled us to find the limit of the commonly used fitting method in terms of a threshold length and a saturation length, where amplification begins and saturation ends, respectively.
Phonon-Induced Wake Potential in a Graphene–Insulator –Graphene Structure
Authors: Kalinić Ana , Radović Ivan , Karbunar Lazar , Despoja Vito , Mišković Zoran L.
Published: December 2024

The aim of this study is to explore the potential which arises in a graphene–insulator–graphene structure when an external charged particle is moving parallel to it with a speed smaller than the Fermi speed in graphene. This is achieved by employing the dynamic polarization function of graphene within the random phase approximation, where its π electrons are modeled as Dirac fermions, and utilizing a local dielectric function for bulk insulators. Three different insulators are considered: SiO2, HfO2, and Al2O3. It is observed that the wake potential is induced by the surface optical phonons originating from the insulator layer, and that total potential could be effectively decomposed into two components, each corresponding to different phonon branches, as long as those branches do not interact amongst themselves.
Artificial Graphite-Based Silicon Composite Anodes for Lithium-Ion Batteries
Authors: Park Sae Min , Salunkhe Tejaswi Tanaji , Yoo Ji Hyeon , Kim Il Ho , Kim Il Tae
Published: December 2024

To develop an advanced anode for lithium-ion batteries, the electrochemical performance of a novel material comprising a porous artificial carbon (PAC)–Si composite was investigated. To increase the pore size and surface area of the composite, ammonium bicarbonate (ABC) was introduced during high-energy ball-milling, ensuring a uniform distribution of silicon within the PAC matrix. The physical and structural properties of the developed material were evaluated using several advanced techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), and galvanostatic intermittent titration (GITT). Artificial graphite contains several macropores that can accommodate volume hysteresis and provide effective sites for anchoring Si nanoparticles, enabling efficient electrochemical reactions. GITT analysis revealed that the PAC-Si-CB-ABC composite exhibited superior lithium-ion diffusion compared to conventional graphite. The developed PAC(55%)-Si(45%)-CB-ABC electrode with PAA as the binder demonstrated a reversible capacity of 850 mAh g−1 at 100 mA g−1 and a high-rate capability of 600 mAh g−1 at 2000 mA g−1. A full cell employing the NCM622 cathode exhibited reversible cyclability of 128.9 mAh g−1 with a reasonable energy density of 323.3 Wh kg−1. These findings suggest that the developed composite is a useful anode system for advanced lithium-ion batteries.
Neuroglia in Neurodegeneration: Exploring Glial Dynamics in Brain Disorders
Authors: Dar Nawab John , Bhat Javeed Ahmad , John Urmilla , Bhat Shahnawaz Ali
Published: December 2024

Neurodegenerative diseases represent a significant global health burden, characterized by progressive loss of neuronal function and structure. While traditionally viewed as primarily neuronal disorders, recent research has highlighted the crucial roles of neuroglia-astrocytes, microglia, and oligodendrocytes in the pathogenesis and progression of these diseases. This review explores the dual nature of glial cells in neurodegenerative processes, focusing on their protective and potentially harmful functions in Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and other neurodegenerative disorders. We examine the complex interactions between different glial cell types and neurons, highlighting recent discoveries in glial-neuronal metabolic coupling, neuroinflammation, and protein aggregation. Advanced technologies, such as single-cell RNA sequencing and spatial transcriptomics, have revealed unprecedented glial heterogeneity and disease-specific glial states, reshaping our understanding of these cells’ roles in health and disease. The review also discusses emerging concepts in neuroglial research, including the role of extracellular vesicles in disease propagation, epigenetic regulation of glial function, and the application of artificial intelligence in glial biology. Finally, we explore the therapeutic implications of targeting glia in neurodegenerative diseases, addressing both the promising avenues and challenges in developing glial-focused interventions. By integrating recent advances in neuroglial research, this review provides a comprehensive overview of the field and highlights future directions for research and therapeutic development. Understanding the complex roles of neuroglia in neurodegenerative diseases is crucial for developing more effective treatments and ultimately improving patient outcomes.
Co-Existent Central and Peripheral Demyelination: Related or Coincidental?
Authors: Narvaez-Caicedo Camila , Jacob Shireen M. , Wu Laura , Patel Chilvana
Published: December 2024

Background: Hereditary Sensory Motor Neuropathy (HSMN) 1A and Multiple Sclerosis (MS) are distinct demyelinating disorders affecting the peripheral and central nervous systems, respectively. We present a case of simultaneous occurrence of both conditions, exploring the clinical presentation, diagnostic workup, and potential interplay between these diseases. Case presentation and clinical approach: A 49-year-old male with a history of optic neuritis presented with progressive numbness, weakness, and sensory loss in all extremities over four years. Neurological examination revealed distal weakness, sensory deficits in a stocking-glove distribution, pes cavus, and hammer toes. Nerve conduction studies and electromyography confirmed sensory motor demyelinating polyneuropathy. The patient’s lack of response to intravenous immunoglobulin therapy suggested hereditary neuropathy as an etiology. Genetic testing identified a PMP22 gene duplication, confirming HSMN 1A. Elevated cerebrospinal fluid protein level and oligoclonal bands, combined with magnetic resonance of the brain showing multiple T2 hyperintense lesions in the brain and spinal cord, fulfilled the diagnostic criteria for MS. Discussion: This case of co-existing HSMN 1A and MS highlights a rare overlap of peripheral and central demyelination. While HSMN 1A results from PMP22 gene duplication, primarily affecting peripheral myelin, MS is driven by immune-mediated central myelin attacks. The co-existence of these disorders suggests potential shared mechanisms, such as immune dysregulation. Some evidence suggests that overexpression of PMP22 in HSMN 1A may disturb immune tolerance, possibly triggering autoimmune responses linked to MS. Further research is needed to explore the genetic and autoimmune interplay between these two diseases, expanding our understanding of demyelinating disorders.