bluuebunny/crossref_metadata_2025 huggingface dataset:
Low Serum Beta-2 Microglobulin Level: A Possible Biomarker for Sarcopenia in the Elderly Population
Authors: Kanat Sahin Ceren , Mete Burak , Demirhindi Hakan , Yaşa Öztürk Gülşah , Ateş Bulut Esra , Kozanoğlu Erkan , Dağlıoğlu Gülçin , Kaya Bülent , Bayram Ertuğrul
Published: November 2024

Background and Objectives: One of the most critical problems regarding sarcopenia is the difficulty of the diagnosis process. This study aimed to determine the prevalence and investigate the role of serum beta-2 microglobulin level as a biomarker for diagnosing sarcopenia. Materials and Methods: This nested case–control study was conducted between 2023 and 2024 on 251 older adults. Muscle strength was measured using a hand dynamometer, and muscle mass was assessed using the bioelectrical impedance method. Individuals with low muscle strength and low muscle mass were accepted as having definitive sarcopenia. Results: The mean age of the 251 older adults included in the study was 72.19 ± 6.11 years. The prevalence of sarcopenia in individuals aged 65 years and over was found to be 5.2%. Serum beta-2 microglobulin levels were statistically significantly lower in sarcopenic participants compared to the control group (p = 0.002). The optimal cut-off value for serum beta-2 microglobulin level was 2.26 mcg/mL, and values lower than this point were found to be diagnostic for sarcopenia. Regarding the cut-off value, the sensitivity was 92.31% and the specificity was 80.77%, the positive predictive value was 70.59%, the negative predictive value was 95.45%, the Youden index was 0.731, and the area under the curve value was 0.901. Individuals who had beta-2 microglobulin levels below 2.26 mcg/mL were found to have a 10.75 times higher risk of sarcopenia. Conclusions: A low serum beta-2 microglobulin level has the potential to be an important candidate biomarker for the diagnosis of sarcopenia.
Pre-Pregnancy Provegetarian Food Pattern and the Risk of Developing Gestational Diabetes Mellitus: The Seguimiento Universidad de Navarra (SUN) Cohort Study
Authors: Bullón-Vela Vanessa , Martínez-Tabar Ainara , Etxezarreta-Uranga Maddi , Martínez-González Miguel Ángel , Basterra-Gortari Francisco Javier , Bes-Rastrollo Maira
Published: November 2024

Background and Objectives: Gestational diabetes mellitus (GDM) is one of the most common medical conditions in pregnancy, with adverse effects on maternal and neonatal outcomes. Evidence suggests a beneficial effect of plant-based dietary patterns, rich in foods derived from plant sources and low in animal foods, on type 2 diabetes; however, their effects on GDM remain unclear. We aimed to investigate the association between pre-pregnancy provegetarian food patterns and the incidence of GDM in a Spanish cohort. Materials and Methods: This subsample of the Seguimiento Universidad de Navarra (SUN) cohort analyzed 3589 Spanish university graduate pregnant women with a mean (standard deviation) age of 28 (±4.3) who were initially free of pre-existing diabetes at baseline. Dietary food consumption was evaluated through a validated, 136-item semi-quantitative food frequency questionnaire. The pre-pregnancy provegetarian food pattern was obtained by assigning positive scores to plant-based food groups and reverse scores to animal food groups. Energy-adjusted quintiles were applied to allocate points to construct the provegetarian food pattern, ranging from 12 to 60 points. Logistic regression models were performed to estimate the odds ratios (OR) of GDM across quintiles of a pre-pregnancy provegetarian food pattern, using the lowest quintile as the reference category. Results: We identified 178 incidence cases of GDM. Women in the highest quintile (Q5) of provegetarian food pattern before pregnancy exhibited a 42% relative reduction in the odds of GDM [adjusted OR (95% CI) Q5 vs. Q1: 0.58 (0.35, 0.97); p-trend = 0.109]. Higher consumption of meat and dairy before pregnancy was associated with a significantly increased risk of GDM [adjusted OR (95% CI) Q5 vs. Q1: 1.94 (1.19, 3.16); p-trend = 0.005] and [adjusted OR (95% CI) Q5 vs. Q1: 1.77 (1.07, 2.94); p-trend = 0.082], respectively. Conclusions: Higher pre-pregnancy consumption of a provegetarian food pattern was associated with a lower risk of developing GDM in Spanish women. Further studies are needed to confirm these findings.
Prevention of Air Embolism in Extracorporeal Membrane Oxygenation Systems: An In Vitro Study on Protection of Central Venous Catheter Lumen
Authors: Franco Danilo , Krasna Nejc , Novak Robert , Esposito Giovanni , Izzo Raffaele , Belohlavek Jan , Noc Marko , Goslar Tomaz
Published: November 2024

Background and Objectives: This study aimed to investigate the risk and mechanisms of air entry into the extracorporeal membrane oxygenation (ECMO) circuit through the central venous catheter (CVC) in a veno-venous configuration. The primary goal was to assess the impact of different air volumes on ECMO circuit performance at varying pump speeds. Material and Methods: The study utilized a circuit model to simulate ECMO conditions and evaluate the potential entry points of air, specifically through the unprotected lumen of the CVC. Various interventions, such as the use of a closed three-way stopcock or clave, were implemented to assess their efficacy in preventing air entry. Results: The unprotected lumen of the central venous catheter posed a significant risk for air entry into the ECMO circuit. The introduction of a closed three-way stopcock or clave proved effective in preventing air ingress through the central venous catheter. Auditory cues, such as a distinct hissing sound, served as an early warning sign of air presence in the circuit. The study demonstrated that even small volumes of air, as minimal as 1 mL, could pass through the oxygenator at specific pump speeds, and larger volumes could lead to pump dysfunction. Conclusions: The study identified the unprotected lumen of the central venous catheter as a potential entry point for air into the ECMO circuit. The use of a closed three-way stopcock or one-way valve was found to be a reliable protective measure against air infiltration. Early detection through the observation of a hissing sound in the circuit provided a valuable warning sign. These findings contribute to enhancing the safety and performance of ECMO systems by minimizing the risk of air embolism.
Evaluation of the Hypothalamic–Pituitary–Adrenal Axis in Patients with Primary Sjögren’s Disease
Authors: Glavina Ana , Zurak Petar , Martinović Dinko , Gotovac Majda , Šupe-Domić Daniela , Lugović-Mihić Liborija
Published: November 2024

Background and Objectives: Patients with primary Sjögren’s disease (pSjD) show contradictory results regarding the activity of the hypothalamic–pituitary–adrenal (HPA) axis. The aim of this study was to determine the salivary cortisol concentration to evaluate the function of the HPA axis (hypoactive/hyperactive) between patients with pSjD and control subjects. Materials and Methods: A total of 34 subjects participated in the cross-sectional study: 17 patients with pSjD and 17 control subjects. Stimulated whole saliva (SWS) was used to determine salivary cortisol concentration using an enzyme-linked immunosorbent assay (ELISA). Results: The salivary cortisol concentration showed a statistically significant difference between patients with pSjD and control subjects (4.69 ± 2.88 vs. 0.49 ± 0.37; p < 0.001; Student t-test). The area under the curve (AUC) was 100.0% in patients with pSjD (p < 0.001). The cut-off point was set to >1.454. The patients with pSjD had four times higher scores for depression and stress and six times higher scores for anxiety compared to the control subjects (p = 0.048, p < 0.001, p = 0.038; Mann–Whitney U test). The patients with pSjD had a statistically significantly higher total Oral Health Impact Profile (OHIP) score compared to the control subjects (p < 0.001, Mann–Whitney U test). Conclusions: The patients with pSjD showed short-term hyperactivity of the HPA axis compared to the control subjects.
Mitochondrial Dysfunction: Effects and Therapeutic Implications in Cerebral Gliomas
Authors: Caruso Gerardo , Laera Roberta , Ferrarotto Rosamaria , Garcia Moreira Cristofer Gonzalo , Kumar Rajiv , Ius Tamara , Lombardi Giuseppe , Caffo Maria
Published: November 2024

Gliomas are the most common primary brain tumors, representing approximately 28% of all central nervous system tumors. These tumors are characterized by rapid progression and show a median survival of approximately 18 months. The therapeutic options consist of surgical resection followed by radiotherapy and chemotherapy. Despite the multidisciplinary approach and the biomolecular role of targeted therapies, the median progression-free survival is approximately 6–8 months. The incomplete tumor compliance with treatment is due to several factors such as the presence of the blood–brain barrier, the numerous pathways involved in tumor transformation, and the presence of intra-tumoral mutations. Among these, the interaction between the mutations of genes involved in tumor bio-energetic metabolism and the functional response of the tumor has become the protagonist of numerous studies. In this scenario, the main role is played by mitochondria, cellular organelles delimited by a double membrane and containing their own DNA (mtDNA), which participates in numerous cellular processes such as the regulation of cellular metabolism, cellular proliferation, and apoptosis and is also the main source of cellular energy production. Therefore, it is understood that the mitochondrion, specifically its functional alteration, is a leading figure in tumor transformation, including brain tumors. The acquisition of mutations in the mitochondrial DNA of tumor cells and the subsequent identification of the so-called mitochondria-related genes (MRGs), both functional (mutation of Complex I) and structural (mutations of Complex III/IV), have been seen to play an important role in metabolic reprogramming with increased proliferation, resistance to apoptosis, and the progression of tumorigenesis. This demonstrates that these mitochondrial alterations could have a role not only in the intrinsic tumor biology but also in the extrinsic one associated with the therapeutic response. We aim to summarize the main mitochondrial dysfunction interactions present in gliomas and how they might impact prognosis.
Application of Additive Manufacturing in Assisted Reproductive Techniques: What Is the Evidence? A Clinical and Technical Systematic Review of the Literature
Authors: Kontogeorgi Adamantia , Boutas Ioannis , Tsangkalova Gkalia , Messaropoulos Pantelis , Koufopoulos Nektarios I. , Schwab Roxana , Makrigiannakis Antonis , Zanelli Magda , Palicelli Andrea , Zizzo Maurizio , Broggi Giuseppe , Caltabiano Rosario , Kalantaridou Sophia N.
Published: November 2024

Background and Objectives: This article investigates the transformative impact of 3D and bio 3D printing technologies in assisted reproductive technology (ART), offering a comprehensive review of their applications in improving reproductive outcomes. Materials and Methods: Following PRISMA guidelines, we conducted a thorough literature search focusing on the intersection of ART and additive manufacturing, resulting in the inclusion of 48 research papers. Results: The study highlights bio 3D printing’s potential in revolutionizing female infertility treatments, especially in follicle complex culture and ovary printing. We explore the use of decellularized extracellular matrix (dECM) as bioink, demonstrating its efficacy in replicating the ovarian microenvironment for in vitro maturation of primordial oocytes. Furthermore, advancements in endometrial cavity interventions are discussed, including the application of sustained-release systems for growth factors and stem cell integration for endometrial regeneration, showing promise in addressing conditions like Asherman’s syndrome and thin endometrium. We also examine the role of conventional 3D printing in reproductive medicine, including its use in educational simulators, personalized IVF instruments, and microfluidic platforms, enhancing training and precision in reproductive procedures. Conclusions: Our review underscores both 3D printing technologies’ contribution to the dynamic landscape of reproductive medicine. They offer innovative solutions for individualized patient care, augmenting success rates in fertility treatments. This research not only presents current achievements but also anticipates future advancements in these domains, promising to expand the horizons for individuals and families seeking assistance in their reproductive journeys.
Substrate-Induced Structural Dynamics and Evolutionary Linkage of Siderophore-Iron ABC Transporters of Mycobacterium tuberculosis
Authors: Farhana Aisha , Alsrhani Abdullah , Ejaz Hasan , Alruwaili Muharib , Alameen Ayman A. M. , Manni Emad , Rasheed Zafar , Khan Yusuf Saleem
Published: November 2024

Background and Objective: ATP-binding cassette (ABC) transporters are prominent drug targets due to their highly efficient trafficking capabilities and their significant physiological and clinical roles. Gaining insight into their biophysical and biomechanistic properties is crucial to maximize their pharmacological potential. Materials and Methods: In this study, we present the biochemical and biophysical characterization, and phylogenetic analysis of the domains of Mycobacterium tuberculosis (M. tuberculosis) ABC transporters: the exporter Rv1348 (IrtA) and the importer system Rv1349-Rv2895c (IrtB-Rv2895c), both involved in siderophore-mediated iron uptake. Results: Our findings reveal that the substrate-binding domain (SBD) of IrtA functions as an active monomer, while Rv2895c, which facilitates the uptake of siderophore-bound iron, exists in a dynamic equilibrium between dimeric and monomeric forms. Furthermore, ATP binding induces the dimerization of the ATPase domains in both IrtA (ATPase I) and IrtB (ATPaseII), but only the ATPase domain of IrtA (ATPase I) is active independently. We also analyzed the stability of substrate binding to the domains of the two transporters across varying temperature and pH ranges, revealing significant shifts in their activity under different conditions. Our study highlights the conformational changes that accompany substrate interaction with the transporter domains, providing insights into the fundamental mechanism required for the translocation of siderophore to the extracytoplasmic milieu by IrtB and, subsequently, import of their ferrated forms by the IrtB-Rv2895c complex. Phylogenetic analyses based on ATPase domains reveal that IrtA shares features with both archaeal and eukaryotic transporters, while IrtB is unique to mycobacterial species. Conclusions: Together, these findings provide valuable insights, which could accelerate the development of intervention strategies for this critical pathway pivotal in the progression of M. tuberculosis infection.
Heart Failure Associated with Giant Uterine Leiomyoma: A Case Report
Authors: Hsu Hai-Ning , Hsu Fang-Chin , Hung Yuan , Hsu Po-Chao , Su Kuo-Min
Published: November 2024

Heart failure impairs the heart’s pumping ability and triggers catecholamine production as an adaptive mechanism. Uterine leiomyomas are common tumors of the female reproductive tract. Their growth is promoted by dysregulated angiogenesis and gonadal steroid hormones. Although uterine leiomyomas share risk factors with most cardiovascular diseases, their relationship with heart failure has not been well described. Herein, we present the case of a 45-year-old woman with heart failure who visited the emergency department, where we incidentally discovered a giant uterine leiomyoma. The patient was admitted with progressive dyspnea and abdominal distension. Echocardiography revealed an enlarged right ventricle and a decreased systolic function. Computed tomography revealed cardiomegaly with bilateral pleural effusions and a tumor measuring 18.0 × 12.0 cm in the abdominal cavity with massive ascites. A diagnosis of heart failure in conjunction with a uterine leiomyoma was established, which prompted the prescription and adjustment of heart failure medications according to the patient’s clinical presentation. Three weeks later, given the persistent symptoms of bilateral lower extremities pitting edema and abdominal distension, a total hysterectomy was performed. Postoperatively, echocardiography revealed marked improvement in her heart failure. The patient was discharged in a stable clinical and hemodynamic conditions, and reported good physical condition at the 4-month follow-up. Growth factors and the compression effect of uterine leiomyomas may predispose patients to heart failure and exacerbate its deterioration. Although reports of fibroid-related heart failure are rare, uterine leiomyomas should be considered a potential cause of refractory heart failure. Nevertheless, a direct association requires a longer follow-up period.
Efficient Separation of Oil/Water by a Biodegradable and Superhydrophobic Composite Based on Loofah and Rice Straw
Authors: Souare Mamadou , Dong Changqing , Xing Tong , Zhang Junjiao , Hu Xiaoying
Published: November 2024

Membrane filtration is one of the preferred choices for petroleum wastewater disposal due to its simplicity and low energy consumption. In this paper, a biodegradable superhydrophobic membrane based on loofah and rice straw (LF-RS) was prepared and modified with dodecyltriethoxysilane to improve its stability, morphology, and performance. The membrane showed an efficiency of 99.06% for oil/water separation with an average water flux of 2057.37 Lm−2h−1 and a tensile strength of 11.19 MPa. The tensile strength of the LF-RS membrane was 322.47% higher than that of the PVDF membrane and 126.58% higher than that of the commercially available nitrocellulose membrane. Through molecular simulations, we showed a 96.3% reduction in interaction energy between water and membrane post-modification, which is beneficial for increasing the contact angle and separation performance. This study provides an option for the large-scale, cost-effective fabrication of eco-friendly membranes for pollutant removal.
Steel Chips as a Raw Material for MEX
Authors: Batista Catarina Duarte , Vieira Maria Teresa Freire
Published: November 2024

In recent years, metal chip powders obtained from solid-state processes have shown great potential as a sustainable raw material for powder technologies. The material and fragmentation process of the chips has a significant role in the final characteristics of the powder particles, such as size and particle size distribution, shape, surface, and structure, which are essential parameters to consider when converting chips to powder for applications. However, tool steel chips as a powder raw material have not yet been significantly studied. In this study, the steel chips were from machining AISI H13 steel and the milling process used a ball mill, and the challenge was to obtain powder particle sizes of around 20 µm with suitable properties from the application of envisaged material extrusion (MEX). A comparison study with the commercial raw material for MEX, such as powder metal filament extrusion, was performed. This study highlights the behaviors of chip powders during all steps of MEX, namely, feedstock and filament production, 3D object shaping, thermal de-binding, and sintering. A comparison of the mixture based on powder from chips and commercial powders for MEX was performed after evaluating the mixing torque of the powder and the system of binders and additives suitable for the rheological characteristics required for an extrusion mixture, and optimizing the binder removal and the sintering conditions. The 3D objects resulting from chip powders had a refined microstructure, showing an increase of 15% in the microhardness when compared with the those resulting from commercial powders.
Quantum Channel Extreme Bandgap AlGaN HEMT
Authors: Shur Michael , Simin Grigory , Hussain Kamal , Mamun Abdullah , Chandrashekhar M. V. S. , Khan Asif
Published: November 2024

An extreme bandgap Al0.64Ga0.36N quantum channel HEMT with Al0.87Ga0.13N top and back barriers, grown by MOCVD on a bulk AlN substrate, demonstrated a critical breakdown field of 11.37 MV/cm—higher than the 9.8 MV/cm expected for the channel’s Al0.64Ga0.36N material. We show that the fraction of this increase is due to the quantization of the 2D electron gas. The polarization field maintains electron quantization in the quantum channel even at low sheet densities, in contrast to conventional HEMT designs. An additional increase in the breakdown field is due to quantum-enabled real space transfer of energetic electrons into high-Al barrier layers in high electric fields. These results show the advantages of the quantum channel design for achieving record-high breakdown voltages and allowing for superior power HEMT devices.
Proposal of a Rapid Detection System Using Image Analysis for ELISA with an Autonomous Centrifugal Microfluidic System
Authors: Okamoto Shunya , Mori Yuto , Nakamura Shota , Kanai Yusuke , Ukita Yoshiaki , Nagai Moeto , Shibata Takayuki
Published: November 2024

In this study, with the aim of adapting an enzyme-linked immunosorbent assay (ELISA) system for point-of-care testing (POCT), we propose an image analysis method for ELISAs using a centrifugal microfluidic device that automatically executes the assay. The developed image analysis method can be used to quantify the color development reaction on a TMB (3,3′,5,5′-tetramethylbenzidine) substrate. In a conventional ELISA, reaction stopping reagents are required at the end of the TMB reaction. In contrast, the developed image analysis method can analyze color in the color-developing reaction without a reaction stopping reagent. This contributes to a reduction in total assay time. The microfluidic devices used in this study could execute reagent control for ELISAs by steady rotation. In the demonstration of the assay and image analysis, a calibration curve for mouse IgG detection was successfully prepared, and it was confirmed that the image analysis method had the same performance as the conventional analysis method. Moreover, the changes in the amount of color over time confirmed that a calibration curve equal to the endpoint analysis was obtained within 2 min from the start of the TMB reaction. As the assay time before the TMB reaction was approximately 7.5 min, the developed ELISA system could detect TMB in just 10 min. In conventional methods using a plate reader, the assay required a time of 90 min for manual handling using microwell plates, and in the case of using automatic microfluidic devices, 30 min were required. The time of 10 min realized by this proposed method is equal to the time required for detection in an immunochromatographic assay with a lateral flow assay; therefore, it is expected that ELISAs can be performed sufficiently to adapt to POCT.
Fused Deposition Modeling of Chemically Resistant Microfluidic Chips in Polyvinylidene Fluoride
Authors: Rein Christof , Hambitzer Leonhard , Soraya Zahra , Zhang Han , Jessen Henning J. , Kotz-Helmer Frederik , Rapp Bastian E.
Published: November 2024

Fused deposition modeling (FDM) is well suited for microfluidic prototyping due to its low investment cost and a wide range of accessible materials. Nevertheless, most commercial FDM materials exhibit low chemical and thermal stability. This reduces the scope of applications and limits their use in research and development, especially for on-chip chemical synthesis. In this paper, we present FDM fabrication of microfluidic chips with polyvinylidene fluoride (PVDF) for applications that require high thermal or chemical resistance. Embedded microchannels with a minimum channel width and heights of ~200 µm × 200 µm were fabricated, and the resistance against common solvents was analyzed. A procedure was developed to increase the optical transmission to result in translucent components by printing on glass. Chips for fluid mixing were printed, as well as microreactors that were packed with a catalytically active phase and used for acetal deprotection with a conversion of more than 99%. By expanding the use of fluorinated polymers to FDM printing, previously challenging microfluidic applications will be conducted with ease at the lab scale.
Design, Testing, and Validation of a Soft Robotic Sensor Array Integrated with Flexible Electronics for Mapping Cardiac Arrhythmias
Authors: Lahcen Abdellatif Ait , Labib Michael , Caprio Alexandre , Annabestani Mohsen , Sanchez-Botero Lina , Hsue Weihow , Liu Christopher F. , Dunham Simon , Mosadegh Bobak
Published: November 2024

Cardiac mapping is a crucial procedure for diagnosing and treating cardiac arrhythmias. Still, current clinical techniques face limitations including insufficient electrode coverage, poor conformability to complex heart chamber geometries, and high costs. This study explores the design, testing, and validation of a 64-electrode soft robotic catheter that addresses these challenges in cardiac mapping. A dual-layer flexible printed circuit board (PCB) was designed and integrated with sensors into a soft robotic sensor array (SRSA) assembly. Design considerations included flex PCB layout, routing, integration, conformity to heart chambers, sensor placement, and catheter durability. Rigorous SRSA in vitro testing evaluated the burst/leakage pressure, block force for electrode contact, mechanical integrity, and environmental resilience. For in vivo validation, a porcine model was used to demonstrate the successful deployment, conformability, and acquisition of electrograms in both the ventricles and atria. This catheter-deployable SRSA represents a meaningful step towards translating the integration of soft robotic actuators and stretchable electronics for clinical use, showcasing the unique mechanical and electrical performance that these designs enable. The high-density electrode array enabled rapid 2 s data acquisition with detailed spatial and temporal resolution, as illustrated by the clear and consistent cardiac signals recorded across all electrodes. The future of this work will lie in enabling high-density, anatomically conformable devices for detailed cardiac mapping to guide ablation therapy and other interventions.
Geochemical Characterization of and Exploration Guide for the World-Class Mafic–Siliciclastic-Hosted Touro VMS Cu Deposit, Northwestern Iberian Peninsula
Authors: Nuñez Pablo , Rubio Alvaro , Arias Daniel , Fuertes-Blanco Jorge , Cortés Fernando , Díaz-Riopa Fernando , Martin-Izard Agustin
Published: November 2024

A geochemical study was conducted on the Touro deposit, which is situated within the Iberian Variscan Massif on the allochthonous terrain of the Galicia–Tras-os-Montes Zone. This study encompassed both mineralogical and geochemical analyses of the host rocks, with a particular focus on the high-grade Fornás metamorphic unit of the Órdenes Complex. The deposit is composed of massive and semi-massive sulfides, the host rocks are amphibolites and paragneisses, and the ore is hosted in garnet amphibolites and mineralized paragneisses. A microscopic study of thin sections and over 300 electron probe microanalyses on various minerals were conducted with the objective of geochemical characterization. Furthermore, a study of approximately 6000 samples processed by mining companies for multielement analyses of over 1350 drill cores was conducted to geochemically characterize the host and mineralized rocks for use as exploration guides. Additionally, five samples underwent Sm-Nd isotope analysis. The data from the Touro Cu (Zn-Co) deposit are consistent with its classification as a mafic–siliciclastic (Besshi-type) VMS deposit constructed in a back-arc environment during the Ordovician period. Following burial and high-grade metamorphism during the Middle Devonian period, these rocks were subsequently exposed during the later Variscan deformation phases, resulting in the formation of the Arinteiro antiform.
Artificial Neural Network-Based Non-Linear Modeling and Simulation of CaO-SiO2-Al2O3-MgO Blast Furnace Slag Viscosity
Authors: dos Anjos Patrick , Coleti Jorge Luís , Junca Eduardo , Grillo Felipe Fardin , Machado Marcelo Lucas Pereira
Published: November 2024

Blast furnace slags are formed by CaO-SiO2-Al2O3-MgO systems and have several physical characteristics, one of which is viscosity. Viscosity is an important variable for the operation and blast furnace performance. This work aimed to model viscosity through linear and non-linear models in order to obtain a model with precision and accuracy. The best model constructed was a non-linear model by artificial neural networks that presented 23 nodes in the first hidden layer and 24 nodes in the second hidden layer with 6 input variables and 1 output variable named ANN 23-24. ANN 23-24 obtained better statistical evaluations in relation to 11 different literature equations for predicting viscosity in CaO-SiO2-Al2O3-MgO systems. ANN 23-24 was also subjected to numerical simulations in order to demonstrate the validation of the non-linear model and presented applications such as viscosity prediction, calculation of the inflection point in the viscosity curve by temperature, the construction of ternary diagrams with viscosity data, and the construction of iso-viscosity curves.
Exploration of the Subsurface Three-Dimensional Structure in Rare Earth Ore Areas Using Electrical Resistivity Tomography: A Case Study in Changting, Fujian, China
Authors: Tang Yingchun , Liu Ping , Jia Shujing , Yang Yang , Mo Yajun , Zhu Jie
Published: November 2024

The development of fracture zones (broken zones) and underground karst rivers in underlying granite can significantly reduce the recovery rate of ion-adsorption-type rare earth ores. Additionally, leaching solutions flowing along unfavorable geological formations can lead to environmental pollution. Therefore, investigating the development of fracture zones (leakage channels) in granite basements is of great significance. In Changting, Fujian, China, several methods have been used in exploration areas (C1 and C2) to study the characteristics of rare ores. This study has focused on the stratigraphic and structural characteristics of the C2 exploration area. Twelve exploration profiles were designed to collect data using electrical resistivity tomography, and a deep electrical structure model of the study area was obtained through inverse calculations. The results indicated that the exploration profiles effectively delineated the thickness of the weathered granite layer and the spatial distribution characteristics of the deep-seated fault structures, which were consistent with the drilling results within the study area. These findings provide important reference materials for the assessment of ion-adsorption-type rare earth ore reserves, blocking leakage channels, and the layout of recovery tunnels.
Superimposed Mineralization in the Xiaorequanzi Cu Deposit, Xinjiang: Evidence from Fluid Inclusions, H-O-S Isotopes, and Pyrite Trace Elements
Authors: Hao Yongqi , Li Shunda , Xia Fang , Chen Chuan , Gao Lingling , Wang Wei , Du Xiaofei , Li Chenmeng
Published: November 2024

The Xiaorequanzi Cu deposit is located in the western part of the Dananhu–Tousuquan Island arc in eastern Tianshan, Xinjiang. It includes stratiform and epithermal-related veinlet mineralization. However, the genesis of this deposit remains controversial. Therefore, fluid inclusions, H–O isotopes, in situ S, and trace elements in pyrite were employed in this study to constrain the origins of the deposit. The Xiaorequanzi Cu deposit’s mineralization stages can be categorized into the following three phases: I. volcanogenic massive sulfide (VMS) mineralization; II. quartz–chalcopyrite–pyrite; and III. quartz–chalcopyrite–sphalerite stages. Fluid inclusion studies suggest that Stage I is distinguished by high-temperature (peak: 320–360 °C) and moderate-salinity (peak: 7–9 wt%) fluids belonging to the H2O–NaCl ± CO2 system. Stages II–III only exhibit vapor–liquid inclusions, with mineralizing fluids belonging to the medium-to-low-temperature (Stage II peak: 160–180 °C; Stage III peak: 120–130 °C) and medium-to-low-salinity (Stage II peak: 5–7 wt%; Atage III peak: 4–6 wt%) H2O–NaCl system. The H–O isotopic data suggest that mineralizing fluid in Stage I is a blend of magmatic and paleo-seawater sources, while in Stages II–III, meteoric water predominates, accompanied by low mineralizing temperatures. In situ S isotope results indicate that the source of mineralizing materials in Stage I (2.52–4.48‰) were magmatic rocks, whereas the markedly higher δ34S values in stages II–III (4.68–6.60‰) suggest sulfur isotope leaching from sedimentary rocks by meteoric water as the main source. The LA–ICP–MS data of pyrite in the Xiaorequanzi Cu deposit suggest that Py1 was formed through volcanic processes, whereas Py2 and Py3 exhibited epithermal characteristics. Throughout the mineralization process, a trend in increasing oxygen and decreasing sulfur fugacity occurred, accompanied by a decreased mineralization temperature. This observation corresponds with the temperature data derived from the fluid inclusions. Additionally, the principal components of different generations of pyrite segregated as two clusters representing the VMS (Stage I) and epithermal mineralization (stages II–III). In summary, based on comprehensive research and previous geochronological studies, it is suggested that the Xiaorequanzi Cu deposit experienced two mineralization stages. The early stage is related to the volcanic activity of the Early Carboniferous (354 Ma), whereas the later stage is associated with Carboniferous–Permian (266–264 Ma) volcanic intrusions.
Evolution of Auriferous Fluids in the Kraaipan-Amalia Greenstone Belts: Evidence from Mineralogical and Isotopic Constraints
Authors: Adomako-Ansah Kofi , Hammond Napoleon Q. , Morishita Yuichi , Ishiyama Daizo
Published: November 2024

The Kraaipan and Amalia greenstone belts in South Africa occur in the western part of the Kaapvaal Craton. The two belts stretch discontinuously in an approximately north–south orientation over a distance of about 250 km from southern Botswana in the north to the Vaal River near Christiana in the south and are separated by a distance of about 90 km. Gold mineralization is hosted in banded iron formation at both the Kalahari Goldridge deposit (Kalgold) in the Kraaipan greenstone belt in the north and the Amalia deposit in the Amalia greenstone belt in the south, with the mineralization associated with quartz–carbonate veins. The footwalls of these deposits are generally composed of mafic volcanic schist and the hanging walls consisting of graywackes, schist and shale units. The Kalgold and Amalia gold deposits show some variation in the redox condition of the mineralizing system and fluid chemistry. The ore mineral assemblage is characterized by magnetite–pyrrhotite–pyrite at Kalgold, which is indicative of reducing conditions, and a magnetite–hematite–pyrite assemblage at Amalia that suggests a relatively oxidizing environment. Average mineralizing temperatures determined from chlorite geothermometry were relatively higher at the Kalahari Goldridge deposit ranging from 350 to 400 °C compared to the slightly cooler range of 330 to 390 °C at Amalia. The composition of the fluids derived from fluid inclusions is indicative of low salinity H2O--CO2±CH4-rich fluids at Kalgold against relatively H2O-CO2-rich fluids at Amalia. Evidence from strontium–carbon–oxygen isotopic ratios from carbonates suggests that differences in redox conditions in the deposits could be attributed to different flow pathways by an evolving fluid from a common source (with minimum 87Sr/86Sr = 0.70354) to the sites of gold deposition, with a significant ore fluid interaction with a thick sequence of carbonaceous meta-pelitic rock units at the Kalahari Goldridge deposit that is absent in the Amalia deposit.
Green Synthesis of Fe2O3 Nanoparticles Using Eucalyptus globulus Leaf Extract on Pinus radiata Sawdust for Cationic Dye Adsorption
Authors: Salgado Pablo , Aedo Eduardo , Vidal Gladys
Published: November 2024

The present study reports the synthesis of Fe2O3 nanoparticles on Pinus radiata sawdust (Fe2O3@PS) using a Eucalyptus globulus leaf extract. The morphology and structure of Fe2O3@PS were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and UV–Vis diffuse reflectance. The adsorption capacity of the system was evaluated by testing its ability to remove the Rhodamine B (RhB) dye. The optimization of the system was carried out using the Plackett–Burman design (PBD) and the response surface methodology (steepest ascent and the Box–Behnken design), which provided information on the main parameters affecting the adsorption process. The PBD results showed that the most important parameters for the removal of RhB using Fe2O3@PS were the removal time, the RhB concentration, and the initial pH of the system. The reusability of Fe2O3@PS under optimal conditions was tested and it was found to maintain its efficiency after five cycles of use. The efficiency and rate of RhB removal observed at pH values near 7.0 were found to be predominantly influenced by electrostatic interactions. In contrast, the analyses conducted at pH values near 8.3 exhibited reduced influence from electrostatic attractions, with π–π interactions and hydrogen bonds emerging as dominant forces. At pH values exceeding 8.3, all potential interactions between RhB and Fe2O3@PS exhibited diminished strength. This research provides valuable information on the formation of eco-friendly nanoparticles immobilized on a forest residue such as sawdust, which can effectively remove organic pollutants like RhB. This contributes to the valorization of resources and the search for solutions to water pollution.
A Comprehensive Microstructure-Aware Electromigration Modeling Framework; Investigation of the Impact of Trench Dimensions in Damascene Copper Interconnects
Authors: Saleh Ahmed Sobhi , Croes Kristof , Ceric Hajdin , De Wolf Ingrid , Zahedmanesh Houman
Published: November 2024

As electronic devices continue to shrink in size and increase in complexity, the current densities in interconnects drastically increase, intensifying the effects of electromigration (EM). This renders the understanding of EM crucial, due to its significant implications for device reliability and longevity. This paper presents a comprehensive simulation framework for the investigation of EM in nano-interconnects, with a primary focus on unravelling the influential role of microstructure, by considering the impact of diffusion heterogeneity through the metal texture and interfaces. As such, the resulting atomic flux and stress distribution within nano-interconnects could be investigated. To this end, a novel approach to generate microstructures of the conductor metal is presented, whereby a predefined statistical distribution of grain sizes obtained from experimental texture analyses can be incorporated into the presented model, making the model predictive under various scales and working conditions with no need for continuous calibration. Additionally, the study advances beyond the state-of-the-art by comprehensively simulating all stages of electromigration including stress evolution, void nucleation, and void dynamics. The model was employed to study the impact of trench dimensions on the dual damascene copper texture and its impact on electromigration aging, where the model findings were corroborated by comparing them to the available experimental findings. A nearly linear increase in normalized time to nucleation was detected as the interconnect became wider with a fixed height for aspect ratios beyond 1. However, a saturation was detected with a further increase in width for lines of aspect ratios below 1, with no effective enhancement in time to nucleation. An aspect ratio of 1 seems to maximize the EM lifetime for a fixed cross-sectional area by fostering a bamboo-like structure, where about a 2-fold of increase was estimated when going from aspect ratio 2 to 1.
High-Performance Ammonia QCM Sensor Based on SnO2 Quantum Dots/Ti3C2Tx MXene Composites at Room Temperature
Authors: Li Chong , Tao Ran , Hou Jinqiao , Wang Huanming , Fu Chen , Luo Jingting
Published: November 2024

Ammonia (NH3) gas is prevalent in industrial production as a health hazardous gas. Consequently, it is essential to develop a straightforward, reliable, and stable NH3 sensor capable of operating at room temperature. This paper presents an innovative approach to modifying SnO2 colloidal quantum dots (CQDs) on the surface of Ti3C2Tx MXene to form a heterojunction, which introduces a significant number of adsorption sites and enhances the response of the sensor. Zero-dimensional (0D) SnO2 quantum dots and two-dimensional (2D) Ti3C2Tx MXene were prepared by solvothermal and in situ etching methods, respectively. The impact of the mass ratio between two materials on the performance was assessed. The sensor based on 12 wt% Ti3C2Tx MXene/SnO2 composites demonstrates excellent performance in terms of sensitivity and response/recovery speed. Upon exposure to 50 ppm NH3, the frequency shift in the sensor is −1140 Hz, which is 5.6 times larger than that of pure Ti3C2Tx MXene and 2.8 times higher than that of SnO2 CQDs. The response/recovery time of the sensor for 10 ppm NH3 was 36/54 s, respectively. The sensor exhibited a theoretical detection limit of 73 ppb and good repeatability. Furthermore, a stable sensing performance can be maintained after 30 days. The enhanced sensor performance can be attributed to the abundant active sites provided by the accumulation/depletion layer in the Ti3C2Tx/SnO2 heterojunction, which facilitates the adsorption of oxygen molecules. This work promotes the gas sensing application of MXenes and provides a way to improve gas sensing performance.
Improvement in Curcumin’s Stability and Release by Formulation in Flexible Nano-Liposomes
Authors: Chen Hua-Wei , Chen Su-Der , Wu Hung-Ta , Cheng Chun-Hung , Chiou Chyow-San , Chen Wei-Ting
Published: November 2024

Curcumin is utilized extensively as Chinese medicine in Asia due to its antioxidant, antimicrobial, and inflammatory activities. However, its use has the challenges of low oral bioavailability and high heat sensitivity. The aim of this research was to produce flexible nano-liposomes containing curcumin using an innovative approach of ethanol injection and Tween 80 to enhance the stability and preservation of curcumin. The mean particle size, encapsulation efficiency, thermal degradation, storage stability, and curcumin release in flexible nano-liposomes were also investigated. We found that the mean particle size of curcumin-loaded flexible nano-liposome decreased from 278 nm to 27.6 nm. At the same time, the Tween 80 concentration increased from 0 to 0.15 wt%, which corresponded with the results of transmission electron microscopy (TEM) morphology analyses, and particle size decreased with an enhancement in Tween 80 concentration. Further, pure curcumin was quickly released within one hour at 37 °C, and first-order kinetics matched with its release curve. However, curcumin encapsulated in flexible nano-liposomes showed a slow release of 71.24% within 12 h, and a slower release pattern matched with the Higuchi model over 24 h, ultimately reaching 84.63% release. Hence, flexible nano-liposomes of curcumin made by a combination of ethanol injection and Tween 80 addition prevented the thermal degradation of curcumin, and enhanced its storage stability and preservation for future drug delivery applications.
Potassium-Based Solid Sorbents for CO2 Adsorption: Key Role of Interconnected Pores
Authors: Zhao Yuan , Huo Jiangbo , Wang Xuefei , Ma Shunwei
Published: November 2024

Industrial CO2 emissions contribute to pollution and greenhouse effects, highlighting the importance of carbon capture. Potassium carbonate (K2CO3) is an effective CO2 absorbent, yet its liquid-phase absorption faces issues like diffusion resistance and corrosion risks. In this work, the solid adsorbents were developed with K2CO3 immobilized on the selected porous supports. Al2O3 had an optimum CO2 adsorption capacity of 0.82 mmol g−1. After further optimization of its pore structure, the self-prepared support Al2O3-2, which has an average pore diameter of 11.89 nm and a pore volume of 0.59 cm3 g−1, achieved a maximum CO2 adsorption capacity of 1.12 mmol g−1 following K2CO3 impregnation. Additionally, the relationship between support structure and CO2 adsorption efficiency was also analyzed. The connectivity of the pores and the large pore diameter of the support may play a key role in enhancing CO2 adsorption performance. During 10 cycles of testing, the K2CO3-based adsorbents demonstrated consistent high CO2 adsorption capacity with negligible degradation.
Exploring Plasmonic Standalone Surface-Enhanced Raman Scattering Nanoprobes for Multifaceted Applications in Biomedical, Food, and Environmental Fields
Authors: Rojas Martínez Valentina , Lee Eunseo , Oh Jeong-Wook
Published: November 2024

Surface-enhanced Raman scattering (SERS) is an innovative spectroscopic technique that amplifies the Raman signals of molecules adsorbed on rough metal surfaces, making it pivotal for single-molecule detection in complex biological and environmental matrices. This review aims to elucidate the design strategies and recent advancements in the application of standalone SERS nanoprobes, with a special focus on quantifiable SERS tags. We conducted a comprehensive analysis of the recent literature, focusing on the development of SERS nanoprobes that employ novel nanostructuring techniques to enhance signal reliability and quantification. Standalone SERS nanoprobes exhibit significant enhancements in sensitivity and specificity due to optimized hot spot generation and improved reporter molecule interactions. Recent innovations include the development of nanogap and core–satellite structures that enhance electromagnetic fields, which are crucial for SERS applications. Standalone SERS nanoprobes, particularly those utilizing indirect detection mechanisms, represent a significant advancement in the field. They hold potential for wide-ranging applications, from disease diagnostics to environmental monitoring, owing to their enhanced sensitivity and ability to operate under complex sample conditions.
Improving Resistive Heating, Electrical and Thermal Properties of Graphene-Based Poly(Vinylidene Fluoride) Nanocomposites by Controlled 3D Printing
Authors: Kotsilkova Rumiana , Georgiev Vladimir , Aleksandrova Mariya , Batakliev Todor , Ivanov Evgeni , Spinelli Giovanni , Tomov Rade , Tsanev Tsvetozar
Published: November 2024

This study developed a novel 3D-printable poly(vinylidene fluoride) (PVDF)-based nanocomposite incorporating 6 wt% graphene nanoplatelets (GNPs) with programmable characteristics for resistive heating applications. The results highlighted the significant effect of a controlled printing direction (longitudinal, diagonal, and transverse) on the electrical, thermal, Joule heating, and thermo-resistive properties of the printed structures. The 6 wt% GNP/PVDF nanocomposite exhibited a high electrical conductivity of 112 S·m−1 when printed in a longitudinal direction, which decreased significantly in other directions. The Joule heating tests confirmed the material’s efficiency in resistive heating, with the maximum temperature reaching up to 65 °C under an applied low voltage of 2 V at a raster angle of printing of 0°, while the heating Tmax decreased stepwise with 10 °C at the 45° and the 90° printing directions. The repeatability of the Joule heating performance was verified through multiple heating and cooling cycles, demonstrating consistent maximum temperatures across several tests. The effect of sample thickness, controlled by the number of printed layers, was investigated, and the results underscore the advantages of programmable 3D printing orientation in thin layers for enhanced thermal stability, tailored electrical conductivity, and efficient Joule heating capabilities of 6 wt% GNP/PVDF composites, positioning them as promising candidates for next-generation 3D-printed electronic devices and self-heating applications.