bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond the Rising Tide: Towards Effective Climate Policy in Coastal Urban Centers
Authors: Rodrigues Elaine Aparecida , Carvalho Amanda Rodrigues de , Ferreira Maurício Lamano , Victor Rodrigo Antonio Braga Moraes , Luca Edgar Fernando de , Rocha Gustavo Casoni da , Carvalho Beatriz Rodrigues de , Bustillos José Oscar Wilian Vega , Sodré Marcelo Gomes , Oliveira Maria Cecília , Jurema Bernardo , Andrade Delvonei Alves de
Published: December 2024

As urban areas expand rapidly, understanding the complex interactions between human migration, climate change impacts, and biodiversity loss is crucial for effective climate policy. However, comprehensive knowledge of the simultaneous interaction of these aspects is still scarce. Thus, this paper proposes the classification of ‘Climate Emergency Coastal Cities’, with the categorization of 43 cities into four levels according to their vulnerability (extreme, very high, high, and critical). Our study contributes to evidence-based climate policy and supports efficient resource allocation and interventions for the most vulnerable coastal cities. Highly anthropogenic megacities were ranked as the most sensitive to climate emergencies (Lagos, Nigeria; Jakarta, Indonesia; Los Angeles and Houston, USA; and Hong Kong and Shenzhen, China). It is noteworthy that in countries from both the Global North and South, the entry of new populations is a critical issue, and represents a threat to urban structures and biodiversity; however, in territories with fragile economies and numerous governance challenges, the required structure is still more challenging. The study concludes that integrated urban planning policies are crucial, considering various perspectives and coordinated actions. Policies should address marginalized urban groups and include migrants, and promote human well-being, ecosystem recovery, and climate mitigation, for effective adaptation.
Enrichment of H3S28p and H3K9me2 Epigenetic Marks on Inflammatory-Associated Gene Promoters in Response to Severe Burn Injury
Authors: Arias-Pérez Osvaldo , Escobedo-Tapia Thelma , Cintora-Ahumada Cecilia , León-Solís Lizbel , Leyva-García Norberto , Aréchaga-Ocampo Elena , Franco-Cendejas Rafael , Hernández-Hernández Oscar , Suárez-Sánchez Rocío
Published: December 2024

Background: Severe burns activate systemic inflammation and lead to an increase in cytokine levels. Epigenetic elements are key regulators of inflammation; however, their involvement in severe burns has not been studied. In this work, we aimed to unveil the histone H3 posttranslational modifications (PTM) profile and their enrichment in promoters of inflammatory genes in response to severe burns. Methods: The levels of H3 PTMs were analyzed by ELISA assays in circulating cells from burn patients. ChIP assays were conducted to evaluate the enrichment of H3K9me2 and H3S28p at the promoter of CXCL8, IL-17, TNFA, IL-6, FOS, and IL-1B genes. Results: We found that eight H3 PTMs decreased at 5 days post-burn. Burn patients showed a decreased enrichment of H3K9me2 in CXCL8, IL-17, and TNFA promoters, whereas IL-6, FOS, and IL-1B promoters displayed an H3S28p enrichment diminution during the first 10 days post-burn. Interestingly, burn-injured septic patients exhibited an increased enrichment of H3K9me2 in TNFA, IL-1B, CXCL8, and IL-17 promoters, whereas H3S28p was increased in promoters of TNFA and IL-1B at 1 dpb. Conclusion: Severe burns trigger epigenetic changes and differential H3 PTM enrichment at inflammation gene promoters. Epigenetic misregulation of H3 may be involved in sepsis occurrence after severe burn injury.
Evaluation of Ocular and Systemic Oxidative Stress Markers in Patients with Diabetic Retinopathy
Authors: López-Contreras Ana Karen , Arévalo-Simental Diana Esperanza , Pacheco-Moisés Fermín Paúl , Martínez-Ruíz María Guadalupe , Olvera-Montaño Cecilia , Robles-Rivera Ricardo Raúl , Sifuentes-Franco Sonia , Campos-Bayardo Tannia Isabel , Huerta-Olvera Selene Guadalupe , Rodríguez-Carrizalez Adolfo Daniel
Published: December 2024

Proliferative diabetic retinopathy (PDR) is the most severe complication of chronic hyperglycaemi stimulates oxidative stress that changes the retinal basement membrane function and provokes neovascularization, macular edema and retinal detachment. But an oxidative–antioxidant biomarker assessment in ocular matrices, such as aqueous humor (AH) and vitreous, might show the oxidative stress (OS) status in the posterior segment. Here, we show a cross-sectional analytical study of 39 patients who had a vitrectomy and assess the levels of different oxidative–antioxidant biomarkers in blood, aqueous and vitreous humor in three groups: diabetes mellitus 2 (DM2) with PDR [DM(+)PDR(+)] (n =13), DM2 without PDR [DM(+)PDR(−)] (n = 13) and non-DM2 non-PDR [DM(−)PDR(−)] as the control group (n = 13). Our finding suggests the presence of oxidative stress in diabetic retinopathy, as evidenced by increased levels of 8-isoprostanes and decreased levels of total antioxidant capacity from stages before the development of diabetic retinopathy. Our results reveal a notable increment in catalase levels in the DM(+)PDR(+) group in blood and vitreous humor. Likewise, we identified that the DM(+)PDR(−) group presents significant levels in 8-IP and SOD in vitreous humor and blood versus aqueous humor. These finding suggest the role of antioxidant enzymes in compensating oxidative stress mechanisms in PDR development.
Arrhythmias Following Patent Foramen Ovale Closure: An Unsolved Enigma
Authors: Karanikola Aikaterini-Eleftheria , Soulaidopoulos Stergios , Leontsinis Ioannis , Dri Eirini , Sagris Marios , Kordalis Athanasios , Aznaouridis Konstantinos , Tsiachris Dimitrios , Tsioufis Konstantinos
Published: December 2024

Patent foramen ovale (PFO) closure has proven to be an effective method of reducing the risk of recurrent stroke in patients with embolic stroke of unknown origin (ESUS). One of the most recognized post-procedural complications is the de novo occurrence of supraventricular arrhythmias, mainly atrial fibrillation, in the first three months following PFO closure. Earlier studies reported the incidence to be around 3.4–7%; however, this percentage has risen in recent studies up to 21%. The pathogenesis behind this type of arrhythmia is complex and not clearly understood, although it seems that direct effects of the device on the atria, as well as an inflammatory response, are the two most prevalent mechanisms. Management of this complication might be challenging given the heterogenicity of patient characteristics, so an individualized approach is most wisely followed. This review aims to present the current data on the incidence, pathogenesis and therapeutic strategies behind this rather common concern in an era of increasing transcatheter interventions for PFO.
RtHSFA9s of Rhodomyrtus tomentosa Positively Regulate Thermotolerance by Transcriptionally Activating RtHSFA2s and RtHSPs
Authors: Li Huiguang , Yang Ling , Fang Yujie , Wang Gui , Liu Tingting
Published: December 2024

Heat shock transcription factors (HSFs) are crucial components in heat stress response. However, the contribution of the HSFs governing the inherent thermotolerance in Rhodomyrtus tomentosa has barely been investigated. We here compared the roles of RtHSFA9a, RtHSFA9b, and RtHSFA9c in heat stress tolerance. These three genes are the results of gene duplication events, but there exist vast variations in their amino acid sequences. They are all localized to the nucleus. Arabidopsis thaliana plants with overexpressed RtHSFA9a and RtHSFA9c outperformed the wild-type plants, while the over-accumulation of RtHSFA9b had little impact on plant thermotolerance. By transiently overexpressing RtHSFA9a, RtHSFA9b, and RtHSFA9c in R. tomentosa seedlings, the mRNA abundance of heat shock response genes, including RtHSFA2a, RtHSFA2b, RtHSP17.4, RtHSP21.8, RtHSP26.5, and RtHSP70, were upregulated. Transactivation assays confirmed that there exist regulatory divergences among these three genes, viz., RtHSFA9a has the highest transcription activity in regulating RtHSFA2a, RtHSFA2b, RtHSP21.8, and RtHSP70; RtHSFA9c can transcriptionally activate RtHSFA2b, RtHSP21.8, and RtHSP70; RtHSFA9b makes limited contributions to the accumulation of RtHSFA2b, RtHSP21.8, and RtHSP70. Our results indicate that the RtHSFA9 genes make crucial contributions to the thermal adaption of R. tomentosa by positively regulating the RtHSFA2a, RtHSFA2b, and RtHSP genes, which provides novel insights into the RtHSFA9 subfamily.
Multicriteria Group Decision Making Based on TODIM and PROMETHEE II Approaches with Integrating Quantum Decision Theory and Linguistic Z Number in Renewable Energy Selection
Authors: Mandal Prasenjit , Mrsic Leo , Kalampakas Antonios , Allahviranloo Tofigh , Samanta Sovan
Published: December 2024

Decision makers (DMs) are often viewed as autonomous in the majority of multicriteria group decision making (MCGDM) situations, and their psychological behaviors are seldom taken into account. Once more, we are unable to prevent both positive and negative flows of varying alternative preferences due to the nature of attributes or criteria in complicated decision-making problems. However, DMs’ perspectives are likely to affect one another in complicated MCGDM issues, and they frequently use subjective limited rationality while making decisions. The multicriteria quantum decision theory-based group decision making integrating the TODIM-PROMETHEE II strategy under linguistic Z-numbers (LZNs) is designed to overcome the aforementioned problems. In our established technique, the PROMETHEE II controls the positive and negative flows of distinct alternative preferences, the TODIM method manages the experts’ personal regrets over a criterion, and the quantum probability theory (QPT) addresses human cognition and behavior. Because LZNs can convey linguistic judgment and trustworthiness, we provide expert LZNs for their viewpoints in this work. We determine the criterion weights for each expert after first obtaining their respective expert weights. Second, to represent the limited rational behaviors of the DMs, the TODIM-PROMETHEE II approach is introduced. It is employed to determine each alternative’s dominance in both positive and negative flows. Third, a framework for quantum possibilistic aggregation is developed to investigate the effects of interference between the views of DMs. The views of DMs are seen in this procedure as synchronously occurring wave functions that affect the overall outcome by interfering with one another. The model’s efficacy is then assessed by a selection of renewable energy case studies, sensitive analysis, comparative analysis, and debate.
Source Quantization and Coding over Noisy Channel Analysis
Authors: Wang Runfeng , Song Dan , Ren Jinkai , Wang Lin , Xu Zhiping
Published: December 2024

Recently, lossy source coding based on linear block code has been designed using the duality principle, i.e., the channel decoding algorithm is employed to realize the lossy source coding. However, the quantization structure has not been analyzed in this compression technique, and the codebook design does not match the source characteristics well. Hence, the compression performance is not so good. To overcome this problem, the codebook design is correlated with the quantization structure in this work. It is found that the lossy source coding based on the linear block code can be defined as lattice vector quantization (VQ), which provides a new analytical perspective for the coding methodology. Then, the VQ scheme is generalized with the noisy channel to evaluate the transmission robustness of the continuous source compression. Finally, the codebook of the VQ scheme is optimally designed by uniforming the radiuses of the quantization subspace to reduce the quantization distortion. The proposed codebook outperforms existing codes in terms of its proximity to the rate–distortion limit, while also exhibiting enhanced robustness against channel noise.
Production Quality Evaluation of Electronic Control Modules Based on Deep Belief Network
Authors: Gong Hua , Xu Wanning , Chen Congang , Sun Wenjuan
Published: December 2024

The electronic control module is an important part of a digital electronic detonator, which undergoes a complex production process that includes three electrical performance tests and three visual inspection procedures. In each inspection procedure, several different types of data are generated daily, including numerical and categorical data. To evaluate the production quality of electronic control modules, an algorithm based on a Deep Belief Network with Multi-mutation Differential Evolution (MDE-DBN) is designed in this study. First, key indicators are extracted to construct a production quality evaluation index system. A Multi-mutation Differential Evolution algorithm is designed to optimize the initial network weights of the Deep Belief Network (DBN) and integrate the production quality information into the pre-training phase. Subsequently, the preprocessed experimental data are input into the MDE-DBN algorithm to obtain the distributions of excellent, general, and unqualified production statuses, verifying the effectiveness of the algorithm. The experimental results show that the MDE-DBN algorithm has significant advantages in evaluation accuracy when compared with DBNs improved by other intelligent optimization algorithms and machine learning methods.
Physical Layer Security Based on Non-Orthogonal Communication Technique with Coded FTN Signaling
Authors: Baek Myung-Sun , Song Hyoung-Kyu
Published: December 2024

In recent years, ensuring communication security at the physical layer has become increasingly important due to the transmission of sensitive information over various networks. Traditional approaches to physical layer security often rely on artificial noise generation, which may not offer robust solutions against advanced interception techniques. This study addresses these limitations by proposing a novel security technique based on non-orthogonal signaling using Faster-than-Nyquist (FTN) signaling. Unlike conventional FTN methods that utilize fixed symbol intervals, the proposed technique employs variable symbol intervals encoded as secure information, shared only with legitimate receivers. This encoding enables effective interference cancellation and symbol detection at the receiver, while preventing eavesdroppers from deciphering transmitted signals. The performance of the proposed technique was evaluated using the DVB-S2X system, a practical digital video broadcasting standard. Simulation results demonstrated that the proposed method maintains smooth communication with minimal performance degradation compared to traditional methods. Furthermore, eavesdroppers were unable to decode the transmitted signals, confirming the enhanced security. This research presents a new approach to physical layer security that does not depend on generating artificial noise, offering a path to more secure and efficient communication systems.
Coupled Alternating Neural Networks for Solving Multi-Population High-Dimensional Mean-Field Games
Authors: Wang Guofang , Fang Jing , Jiang Lulu , Yao Wang , Li Ning
Published: December 2024

Multi-population mean-field game is a critical subclass of mean-field games (MFGs). It is a theoretically feasible multi-agent model for simulating and analyzing the game between multiple heterogeneous populations of interacting massive agents. Due to the factors of game complexity, dimensionality disaster and disturbances should be taken into account simultaneously to solve the multi-population high-dimensional stochastic MFG problem, which is a great challenge. We present CA-Net, a coupled alternating neural network approach for tractably solving multi-population high-dimensional MFGs. First, we provide a universal modeling framework for large-scale heterogeneous multi-agent game systems, which is strictly expressed as a multi-population MFG problem. Next, we generalize the potential variational primal–dual structure that MFGs exhibit, then phrase the multi-population MFG problem as a convex–concave saddle-point problem. Last but not least, we design a generative adversarial network (GAN) with multiple generators and multiple discriminators—the solving network—which parameterizes the value functions and the density functions of multiple populations by two sets of neural networks, respectively. In multi-group quadcopter trajectory-planning numerical experiments, the convergence results of HJB residuals, control, and average speed show the effectiveness of the CA-Net algorithm, and the comparison with baseline methods—cluster game, HJB-NN, Lax–Friedrichs, ML, and APAC-Net—shows the progressiveness of our solution method.
A Comprehensive Study of Dynamical Behavior and Nonlinear Structures of the Modified α Equation
Authors: Almusawa Hassan , Almusawa Musawa Yahya , Jhangeer Adil , Hussain Zamir
Published: December 2024

In this article, the modified α equation is solved using the direct algebraic approach. As a result, numerous new and more generalized exact solutions for such equations have been found, taking into account the wide range of travelling structures. The rational, trigonometric, hyperbolic, and exponential functions with a couple of licentious parameters are thus included in these exact answers. Analytical solutions feature a variety of physical structures, which are visually studied to demonstrate their dynamic behavior in 2D and 3D. Considering the parameters, all feasible phase portraits are shown. Furthermore, we used numerical approaches to determine the nonlinear periodic structures of the mentioned model, and the data are graphically displayed. Additionally, we employed numerical approaches to determine the nonlinear conditions that contribute to the presented model, and the data are graphically displayed. After evaluating the influence of frequency following the application of an external periodic factor, sensitivity exploration is used to study quasi-periodic and chaotic behavior for several starting value problems. Furthermore, the function of physical characteristics is investigated using an external periodic force. Quasi-periodic and quasi-periodic-chaotic patterns are described with the inclusion of a perturbation term. The direct algebraic methodology would be used to derive the soliton solution of modified α equation, from which the Galilean transformation derives traveling wave solutions of the considered and a bifurcation behavior is reported. Analytical and numerical methods have been used to have the condition of the travelling wave phase transformation. The well-judged values of parameters are enhanced well with a graphically formal analysis of such specific solutions to illustrate their propagation. Then a planer dynamical system is introduced, and a bifurcation analysis is utilized to identify the bifurcation structures of the dynamical model’s nonlinear wave propagation solutions. Additionally, the periodic and quasi-periodic behavior of the discussed equation is analyzed using sensitivity analysis for a range of beginning values. To further comprehend the dynamical behaviors of the resultant solutions, a graphic analysis is conducted.
High-Cycle Fatigue Characteristics of Aluminum/Steel Clinched and Resistance-Spot-Welded Joints Based on Failure Modes
Authors: Meilinger Ákos , Kovács Péter Zoltán , Lukács János
Published: December 2024

Materials for lightweight vehicle structures play an increasingly important role in both economic and environmental terms; high-strength steels and aluminum alloys are suitable for this role. Resistance spot welding (RSW) and conventional clinching (CCL) methods can be used for joining vehicle bodies and can also be applied for aluminum/steel hybrid joints. Whereas vehicle structures are subjected to cyclic loading, damages can occur due to high-cycle fatigue (HCF) during long-term operation. Systematic HCF test results are rarely found in the literature, while HCF loading basically determines the lifetime of the hybrid joints. The base materials 5754-H22, 6082-T6, and DP600 were used for similar and hybrid RSW and CCL joints, and HCF tests were performed. The number of cycles-to-failure values and failure modes were studied and analyzed. Based on the experimental results, HCF design curves belonging to a 50% failure probability were calculated for all cases, and the curves were compared. Clear relationships were found between the failure modes and fatigue cycle numbers for both joining methods. Considering the steel/steel joints as a base, the load-bearing capacity of the hybrid joints is lower (48.7% and 73.0% for RSW, 35.0% and 38.7% for CCL) and it is even lower for the aluminum/aluminum joints (39.9% and 50.4% for RSW, 31.7% and 35.0% for CCL). With one exception, the load-bearing capacity of the CCL joints is higher than that of the RSW joints (156.1–108.3%).
Characterization of Physical and Chemical Properties of Multi-Source Metallurgical Dust and Analysis of Resource Utilization Pathways
Authors: Zhang Jiansong , Zhang Yuzhu , Long Yue , Tian Chen , Du Peipei , Ren Qianqian
Published: December 2024

Steel metallurgical dust, characterized by a substantial output, minute particle size, and intricate composition, poses a considerable risk of environmental contamination while simultaneously embodying an exceptionally high potential for recycling. To achieve its resource utilization, chemical analysis, particle size analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), Mössbauer spectroscopy, and water leaching methods were employed to investigate the chemical compositions, particle size distributions, phase compositions, and microscopic morphologies of blast furnace bag dust, sintering dust, converter fine dust, and electric arc furnace dust from steel plants. The results indicate that the four types of dust have extremely fine particle sizes, with the main distribution range of particle size being less than 100 μm. The main constituent element is Fe (19–56%), and it also contains Zn (1.4–33.5%), Pb, K, C, and other valuable elements. Alkali metals in blast furnace bag dust and sintering machine head dust existed mainly in the form of chloride. The zinc phases in sintering machine head dust and converter fine dust were ZnFe2O4, and the zinc phases in blast furnace bag dust were ZnCl2 and ZnFe2O4. Zinc in electric furnace dust was composed of ZnO and ZnFe2O4, accounting for 70.31% and 23.12%, respectively. There are significant differences in the types and contents of valuable elements among various dusts, making it difficult to achieve full-scale recovery through a single process. In view of this, a process of “in-plant recycling of harmless dusts—collaborative treatment of harmful dusts” has been proposed. Based on the characteristics of metallurgical dusts, multiple processes are used for collaborative treatment (using hydrometallurgical and pyrometallurgical methods), which can not only directly recover iron resources from dusts within the plant, but also avoid the waste of valuable elements such as Zn, Pb, K, Na, etc. It is hoped that the above work can provide a reference for steel enterprises to achieve full-scale and high value-added treatment of metallurgical dusts.
Hot Bending–Quenching Characteristics of Heat Treatable A6063 Aluminum Tubes
Authors: Kwon Euipyo , Park Hyunkyung , Yang Junghoon
Published: December 2024

This study investigates the application of hot bending–quenching technology to heat-treatable A6063 aluminum tubes, focusing on the bending formability and mechanical properties after aging treatment under various heating conditions. High-frequency induction heating was used to uniformly heat aluminum tubes to the solution treatment temperature of 560 °C. The effect of wall thickness on bending formability was explored, revealing that thinner tubes (2 mm) experienced significant flattening defects, whereas thicker tubes (5 mm) exhibited superior formability with reduced shrinkage and wall thinning. Additionally, the pre-quenching temperature was found to influence the mechanical properties of the tube with a thickness of 5 mm. Tubes held at the solution temperature for 1 min 30 s or longer maintained higher temperatures during transfer, resulting in improved tensile strength and hardness after aging. The findings confirm the feasibility of applying hot bending–quenching technology to aluminum tubes, though careful control of temperature loss during continuous industrial processes is required to ensure optimal mechanical performance.
Structural, Magnetic, and Mössbauer Study on Nb and Heat Treatment of Fe-Si-B-P-Cu-Nb Ribbons
Authors: Lee Hyunkyung , Choi Hyunkyung , Uhm Young Rang , Choi-Yim Haein
Published: December 2024

This study aims to enhance the amorphous formation ability and magnetic properties that are crucial for the production of high-quality nanocrystalline alloys. The structural, thermal, and magnetic characteristics of the alloy ribbons were analyzed through a systematic adjustment of Nb content, and, including Nb, significantly improved the amorphous formation ability and thermal stability of the alloy, which is vital for nanocrystalline production. By varying the Nb content within Fe85-xSi2B8P4Cu1Nbx (x = 0.0, 0.5, 1.0, and 1.5), we explored finer adjustments to achieve homogeneous amorphousness during the melt spinning process. Careful control over the Nb content facilitated the production of amorphous ribbons with consistent homogeneity, which was critical for the subsequent fabrication of nanocrystalline structures through heat treatment. As a result, the amorphous ribbon of Fe85.5Si2B8P4Cu1Nb0.5 showed a low coercivity of 7 A/m. The heat treatment showed a remarkably high saturation magnetic flux density of 1.94 T. Additionally, the grain size (D) decreased as the Nb content increased, with D values ranging from 25.09 nm to 24.29 nm, as calculated by the Scherrer formula. Mössbauer spectroscopy confirmed the formation of nanocrystalline and residual amorphous phases. The hyperfine magnetic field values (Beff) decreased from 25.7 T to 24.7 T in the amorphous samples and reached 33.0 T in the nanocrystalline phases. This study highlights Nb’s positive impact on thermal stability and amorphous formation capacity in Fe-Si-B-P-Cu alloys, culminating in the successful fabrication of nanocrystalline ribbons with superior structural and magnetic properties.
Impact of Conventional and Laser-Assisted Machining on the Microstructure and Mechanical Properties of Ti-Nb-Cr-V-Ni High-Entropy Alloy Fabricated with Directed Energy Deposition
Authors: Jeong Ho-In , Salem Osama , Jung Dong-Won , Lee Choon-Man , Lee Jeung-Hoon
Published: December 2024

The high-entropy alloy (HEA) has recently attracted significant interest due to its novel alloy design concept and exceptional mechanical properties, which may exhibit either a single or multi-phase structure. Specifically, refractory high-entropy alloys (RHEA) composed of titanium, niobium, and nickel-based HEA demonstrate remarkable mechanical properties at elevated temperatures. Additive manufacturing (AM), specifically Direct Energy Deposition (DED), is efficient in fabricating high-entropy alloys (HEA) owing to its fast-cooling rates, which promote uniform microstructures and reduce defects. This study involved the fabrication of the Ti33Nb28Cr11V11Ni17 (Ti-Nb-Cr-V-Ni) RHEA utilizing DED. Additionally, the post-processing of the fabricated alloy is conducted using conventional machining (CM) and laser-assisted machining (LAM). The results indicate thermal conductivity and specific heat increased, whereas tensile strength reduced with rising temperature. Significant softening was observed above 800 °C, resulting in a considerable decrease in tensile strength. Furthermore, the LAM caused material softening and reduced the cutting force by 60.0% relative to CM. Furthermore, the chemical composition of Ti-Nb-Cr-V-Ni remained unaffected even after post-processing with CM and LAM. The research indicates that post-processing with LAM is essential for developing resilient RHEA for practical use.
Determination of the Minimum Uncut Chip Thickness of Ti-6Al-4V Titanium Alloy Based on Dead Metal Zone
Authors: Zheng Yaohui , Huang Wentao , Liu Yangyang , Duan Pengchao , Wang Yingxiao
Published: December 2024

In Ti-6Al-4V titanium alloy micro-machining, since the uncut chip thickness (UCT) is comparable to the radius of the tool cutting edge, there exists a minimum uncut chip thickness (MUCT), and when the UCT is smaller than the MUCT, the plowing effect dominates the cutting process, which seriously affects the machined surface quality and tool life. Therefore, the reliable prediction of the MUCT is of great significance. This paper used Deform to establish an orthogonal cutting simulation model, studied the effect of the dead metal zone (DMZ) on the micro-cutting material flow, determined the DMZ range, and proposed a new method for determining the MUCT based on the DMZ. Cutting experiments were conducted to verify the accuracy of the simulation model firstly by cutting force, and then confirming the accuracy of the DMZ-based MUCT determination method through chip analysis and surface quality analysis. Finally, the effects of different cutting conditions on DMZ and MUCT were further investigated using the proposed DMZ-based MUCT determination method. The results show that the MUCT of Ti-6Al-4V titanium alloy is 4.833 μm for a tool cutting edge radius of 40 μm and a cutting speed of 10 m/min. The DMZ boundary can be used as the boundary of micro-cutting plastic deformation, and the ratio of MUCT to cutting edge radius, hp/rn will gradually decrease with the increase in the tool cutting edge radius and the cutting speed.
Microelectromechanical System Resonant Devices: A Guide for Design, Modeling and Testing
Authors: Viola Carolina , Pavesi Davide , Weng Lichen , Gobat Giorgio , Maspero Federico , Zega Valentina
Published: December 2024

Microelectromechanical systems (MEMSs) are attracting increasing interest from the scientific community for the large variety of possible applications and for the continuous request from the market to improve performances, while keeping small dimensions and reduced costs. To be able to simulate a priori and in real time the dynamic response of resonant devices is then crucial to guide the mechanical design and to support the MEMSs industry. In this work, we propose a simplified modeling procedure able to reproduce the nonlinear dynamics of MEMS resonant devices of arbitrary geometry. We validate it through the fabrication and testing of a cantilever beam resonator functioning in the nonlinear regime and we employ it to design a ring resonator working in the linear regime. Despite the uncertainties of a fabrication process available in the university facility, we demonstrate the predictability of the model and the effectiveness of the proposed design procedure. The satisfactory agreement between numerical predictions and experimental data proves indeed the proposed a priori design tool based on reduced-order numerical models and opens the way to its practical applications in the MEMS industry.
Resolution Enhancement Strategies in Photoacoustic Microscopy: A Comprehensive Review
Authors: Zhang Jinying , Shi Yifan , Zhang Yexiaotong , Liu Haoran , Li Shihao , Liu Linglu
Published: December 2024

Photoacoustic imaging has emerged as a promising modality for medical imaging since its introduction. Photoacoustic microscopy (PAM), which is based on the photoacoustic effect, combines the advantages of both optical and acoustic imaging modalities. PAM facilitates high-sensitivity, high-resolution, non-contact, and non-invasive imaging by employing optical absorption as its primary contrast mechanism. The ability of PAM to specifically image parameters such as blood oxygenation and melanin content makes it a valuable addition to the suite of modern biomedical imaging techniques. This review aims to provide a comprehensive overview of the diverse technical approaches and methods employed by researchers to enhance the resolution of photoacoustic microscopy. Firstly, the fundamental principles of the photoacoustic effect and photoacoustic imaging will be presented. Subsequently, resolution enhancement methods for both acoustic-resolution photoacoustic microscopy (AR-PAM) and optical-resolution photoacoustic microscopy (OR-PAM) will be discussed independently. Finally, the aforementioned resolution enhancement methods for photoacoustic microscopy will be critically evaluated, and the current challenges and future prospects of this technology will be summarized.
Quantitative Analysis of the Effect of Fluorescent Labels on DNA Strand Displacement Reaction
Authors: Toyonari Masato , Aso Kaori , Nakakuki Takashi
Published: December 2024

DNA chemical reaction networks can perform complex information processing through careful design of reaction kinetics, which involves the reaction network structure, rate constants, and initial concentrations. The toehold-mediated strand displacement reaction (TMSDR) is a key mechanism in creating DNA circuits, offering a rational design approach by integrating individually designed TMSDRs. Tools such as VisualDSD and NUPACK facilitate the efficient design of these systems by allowing precise tuning of reaction parameters. However, discrepancies between simulated and experimental results can occur, often due to the modification of reporter molecules. Recently, fluorophore dyes and quenchers were found to significantly impact the dynamics of irreversible TMSDRs, altering them by nearly two orders of magnitude. The impact on reaction dynamics varies with the modification site of these reporters. This study examines the mechanisms of reporter modifications affecting reversible TMSDRs, influencing transient and steady-state characteristics. This is crucial for DNA circuit design, which integrates reversible and irreversible TMSDRs. Our findings indicate that modifying fluorescent dye and quencher an appropriate distance apart (e.g., toehold length) can minimize adverse effects on the DNA reaction dynamics while ensuring effective FRET, therefore improving the accuracy of experimental verification for DNA reaction systems.
Critical Design and Operating Parameters of Active Waveguide Bragg Gratings for Laser Performance
Authors: Sanz-Felipe Ángel , Vallés Juan A.
Published: December 2024

Active waveguide Bragg gratings (AWBGs) are promising photonic structures that combine the very efficient reflective properties of a Bragg grating with the power amplification character of rare earths. This combination may lead to a potential monolithic laser under the proper conditions. However, the photonic response of these structures highly depends on the grating design and operating parameters, so modeling its response for their laser performance is a must. In this work, a numerical method is employed to calculate the optical power propagation along an Er/Yb-codoped integrated AWBG. A complete database of the AWBG response as a function of the most relevant operational parameters is obtained. As a result, the critical values of each design and operating parameter to achieve its laser performance have been determined, which represents very useful information for further experimental design, optimization, and fabrication of these photonic structures.
Assessment of Surface Integrity in Precision Electrical Discharge Machining of HSS EN HS6-5-2C
Authors: Straka Ľuboslav , Piteľ Ján , Čorný Ivan
Published: December 2024

The integrity of the machined surface in precision wire electrical discharge machining (WEDM) of electrically conductive materials is one of the most important quality indicators. The integrity parameters of the machined surface are primarily monitored in terms of micro and macro geometry parameters. This paper presents the results obtained as a part of experimental research aimed at evaluating surface crack density (SCD) when machining EN HS6-5-2C using WEDM technology. The aim was to find a combination of main technological parameters (MTP) in order to minimize the qualitative indicators SCD and Ra of the eroded surface. The results of experimental research within the framework of the evaluation of SCD and Ra indicators were processed using the Taguchi method. The integrity of the eroded surface was examined by scanning digital microscope (SDM) after application of full and multiple offset cuts with an AC Brass LP 1000 brass wire electrode. Based on the experimental measurements performed, significant facts were discovered. It was found that the largest surface integrity defects are present after the application of full cuts and the first two offset cuts. At the same time, it was found that lower values of the SCD parameter in WEDM of EN HS6-5-2C steel were recorded at thicknesses above 130.0 mm. The SCD parameter was also confronted with the Ra parameter, and it was found that they are significantly influenced by MTP. The higher value of the peak current I (19 A) and the longer duration of the discharge ton (32 μs) result in an increase in the value of the SCD parameter from 0.005 μm·μm−2 to 0.0256 μm·μm−2. The resulting solutions are mathematical regression models (MRM), which allow the prediction of both monitored qualitative indicators with respect to their minimization.
Impact of Sample Storage Time and Temperature on the Stability of Respiratory Viruses and Enteric Viruses in Wastewater
Authors: Qiu Judy Y. , Mah Richardson , Brand Logan A. , Pang Xiaoli , Barnett Melodie , Diggle Mathew , Tipples Graham
Published: December 2024

Wastewater-based surveillance (WBS) has been widely used to track SARS-CoV-2 as well as many other viruses in communities during the COVID pandemic and post-pandemic. However, it is still not clear how temperature and storage time would influence the stability of viruses in wastewater. In this study, we assessed the stability of SARS-CoV-2, pepper mild mottle virus (PMMoV), influenza viruses A (IAV) and B (IBV), respiratory syncytial virus (RSV), and enteric viruses in raw wastewater stored at room temperature, 4 °C, and −20 °C for 3 and 6 days. SARS-CoV-2, PMMoV, IAV, and enteric viruses were found to be stable up to 6 days after storing at room temperature or 4 °C. SARS-CoV-2 and RSV were more susceptible to freeze–thaw cycles compared to PMMoV and enteric viruses, which were relatively stable for up to 6 days stored at −20 °C. Low detection of IBV in wastewater made it difficult to evaluate the impact. Based on our findings, we conclude that short-term storage or transportation of wastewater samples within 6 days at ambient temperature or 4 °C is acceptable for the majority of these viruses. Freezing samples at −20 °C for even short periods is not recommended for WBS of respiratory viruses. The data obtained from this study can provide guidance for quality assurance purposes from the operational aspects of wastewater surveillance.
Effects of mscM Gene on Desiccation Resistance in Cronobacter sakazakii
Authors: Zhu Dongdong , Zhang Zhengyang , Li Ping , Du Xinjun
Published: December 2024

Cronobacter sakazakii, an opportunistic foodborne pathogen, has a strong resistance to osmotic stress and desiccation stress, but the current studies cannot elucidate this resistance mechanism absolutely. A mechanosensitive channel MscM was suspected of involving to desiccation resistance mechanism of C. sakazakii. To investigate the specific molecular mechanism, the mscM mutant strain (ΔmscM) was constructed using the homologous recombination method, and the cpmscM complementary strain was obtained by gene complementation, followed by the analysis of the difference between the wild-type (WT), mutant, and complementary strains. Compared to the wild-type bacteria (WT), the inactivation rate of the ΔmscM strain decreased by 15.83% (p < 0.01) after desiccation stress. The absence of the mscM gene led to an increase in the membrane permeability of mutant strains. Through turbidity assay, it was found that the intracellular content of potassium ion (K+) of the ΔmscM strain increased by 2.2-fold (p < 0.05) compared to the WT strain, while other metal ion contents, including sodium ion (Na+), calcium ion (Ca2+), and magnesium ion (Mg2+), decreased by 48.45% (p < 0.001), 24.29% (p < 0.001), and 26.11% (p < 0.0001), respectively. These findings indicate that the MscM channel primarily regulates cell membrane permeability by controlling K+ efflux to maintain the homeostasis of intracellular osmotic pressure and affect the desiccation tolerance of bacteria. Additionally, the deletion of the mscM gene did not affect bacterial growth and motility but impaired surface hydrophobicity (reduced 20.52% compared to the WT strain, p < 0.001), adhesion/invasion capability (reduced 26.03% compared to the WT strain, p < 0.001), and biofilm formation ability (reduced 30.19% compared to the WT strain, p < 0.05) of the bacteria. This study provides a reference for the role of the mscM gene in the desiccation resistance and biofilm formation of C. sakazakii.
Mineralogical Characteristics and Purification Experiments of Quartz from a Pegmatite: A Case Study in the Lushi Region of the Qinling Orogenic Belt, Central China
Authors: Magar Jamuna Thapa , Yang Xiaoyong , Li Kaiwen , Xia Mei , Li Xiaoyu , Cai Zhichao
Published: December 2024

This study uses a sample of pegmatite (LS-1) from the Longquanping deposit in Lushi County, Henan Province, to evaluate its potential as a valuable source of HPQ. This investigation uses various analytical techniques to assess the quality of quartz and its suitability for industrial applications. The methods used in this study include optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, X-ray fluorescence spectrometry (XRF), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and inductively coupled plasma mass spectrometry (ICP-MS) to analyze the petrographic, mineralogical, and trace element characteristics of quartz before and after purification and comprehensively evaluate the potential of quartz in these rocks as an HPQ raw material ore. The optical and scanning electron microscopic observations reveal several impurities and associated minerals in quartz, including feldspar, biotite, magnetite, sphene, and large number of fluid inclusions composed of both gas and liquid phases. The content of trace element in raw quartz ore in the LS-1 sample as determined by LA-ICP-MS analysis ranges from 41.61 to 256.13 ppm, with the main impurity elements being Al, Ti, Li, Na, K, and Ca. After purification, the SiO2 contents and total trace elements contents of the LS-1 refined quartz sand was 99.997 wt.% and 29.29 ppm, respectively, with Al (13.29 ppm), Ti (4.20 ppm), Li (1.15 ppm), and Na (10.32 ppm). The major trace element contents of Al and Ti in the quartz concentrates were lower than the upper limit of the HPQ standard and thus belonged to the high-end products (4N8). Results of this study show that quartz from a pegmatite in the Lushi region has the potential to be purified HPQ. This study underscores the importance of thorough mineralogical and elemental analyses in assessing the suitability of quartz raw material deposits for HPQ production.
Granites of the Chazangcuo Copper–Lead–Zinc Mining Area in Tibet, China: Magma Source and Tectonic Implications
Authors: Li Yan , Wang Jianguo , Wei Shengyun , Hu Jian , Wang Zhinan , Ge Jiawen
Published: December 2024

Intermediate-acidic granites occur extensively in the Chazangcuo copper-lead-zinc mining area (hereinafter referred to as the Chazangcuo mining area) in Tibet, China. Exploring their rock types, sources, and tectonic settings is essential for understanding the genesis of granites in the region. This study investigated the petrology of the Chazangcuo granites, as well as the geochemical characteristics of their major elements, trace elements, and rare earth elements (REEs). Results indicate that the Chazangcuo granites are high-K calc-alkaline metaluminous rocks. These granites are enriched in large-ion lithophile elements (LILEs; e.g., Rb and Ba), depleted in high-field-strength elements (HFSEs; e.g., Nb, Ta, Zr, and Hf), with a relative enrichment in light rare earth elements (LREEs), and relatively depleted in heavy rare earth elements (HREEs), exhibiting a V-shaped distribution pattern and weak negative Eu anomalies. The granites are classified as typical I-type granites, displaying characteristics of crust-derived magmas with contributions from mantle sources and exhibiting significant fractional crystallization. The Chazangcuo granites were derived from the partial melting of mafic rocks, with protoliths formed in a moderate temperature environment. Influenced by the subduction of the Neotethys Ocean, the Chazangcuo granites were formed in an arc caused by the collision between the Indian and Eurasian plates (also referred to as the Indo–Eurasian collision) during the Late Triassic. Under the effect of geological activities such as upwelling of the asthenosphere and fluid intrusion and differentiation, metal mineralization was prompted to be distributed in the granite fissures, forming the Cu-Pb-Zn polymetallic deposits of Chazangcou in Tibet, suggesting that the granites are closely associated with mineralization.
Recovery of Copper from Slags Through Flotation at the Hernán Videla Lira Smelter
Authors: Valderrama Luis , Tapia Jaime , Pavez Osvaldo , Santander Mario , Rivera Víctor , Gonzalez Miguel
Published: December 2024

The significant volume of copper smelting slags poses environmental challenges, particularly concerning soil and surface water contamination. However, these slags contain valuable elements such as copper and iron, the recovery of which can contribute to both environmental protection and the circular economy in Chile. This study analyzes, at both laboratory and industrial scales, the recovery of copper sulfides from the slags of the Hernán Videla Lira Smelter in Atacama, Chile. Physical, chemical, and mineralogical characterizations were performed, along with flotation tests (rougher and cleaner) to optimize the grinding degree, pH, reagents, and flotation times. The slag, with a copper grade of 0.71%, contains fayalite, magnetite, quartz, pyrite, and chalcopyrite. In the laboratory, the concentrate obtained in the rougher stage showed a copper grade of 3.7% with a recovery rate of 62.1%; in the cleaner stage, the grade increased to 24.4%, with a recovery rate of 71.7%. At the industrial level, the rougher–cleaner circuit produced concentrates with a copper grade of 27.9% and a recovery rate of 87.5% processing 1344 tons per day, thus demonstrating the viability of this methodology.
Laser-Induced Graphene Decorated with MOF-Derived NiCo-LDH for Highly Sensitive Non-Enzymatic Glucose Sensor
Authors: Li Longxiao , Han Yufei , Zhang Yuzhe , Wu Weijia , Du Wei , Wen Guojun , Cheng Siyi
Published: December 2024

Designing and fabricating a highly sensitive non-enzymatic glucose sensor is crucial for the early detection and management of diabetes. Meanwhile, the development of innovative electrode substrates has become a key focus for addressing the growing demand for constructing flexible sensors. Here, a simple one-step laser engraving method is applied for preparing laser-induced graphene (LIG) on polyimide (PI) film, which serves as the sensor substrate. NiCo-layered double hydroxides (NiCo-LDH) are synthesized on LIG as a precursor, utilizing the zeolitic imidazolate framework (ZIF-67), and then reacted with Ni(NO3)2 via solvent-thermal methods. The sensitivity of the non-enzymatic electrochemical glucose sensor is significantly improved by employing NiCo-LDH/LIG as the sensing material. The porous and interconnected structure of NiCo-LDH, derived from ZIF-67, enhances the accessibility of electrochemically active sites, while the incorporation of LIG ensures exceptional conductivity. The combination of NiCo-LDH with LIG enables efficient electron transport, leading to an increased electrochemically active surface area and enhanced catalytic efficiency. The fabricated electrode achieves a low glucose detection limit of 0.437 μM and demonstrates a high sensitivity of 1141.2 and 631.1 μA mM−2 cm−2 within the linear ranges of 0–770 μM and 770–1970 μM, respectively. Furthermore, the NiCo-LDH/LIG glucose sensor demonstrates superior reliability and little impact from other substances. A flexible integrated LIG-based non-enzymatic glucose sensor has been developed, demonstrating high sensitivity and suggesting a promising application for LIG-based chemical sensors.