bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the Impact of Flavonoids on Aspergillus flavus: Insights into Cell Wall Damage and Biofilms
Authors: Castano-Duque Lina , Lebar Matthew D. , Mack Brian M. , Lohmar Jessica M. , Carter-Wientjes Carol
Published: September 2024

Aspergillus flavus, a fungus known for producing aflatoxins, poses significant threats to agriculture and global health. Flavonoids, plant-derived compounds, inhibit A. flavus proliferation and mitigate aflatoxin production, although the precise molecular and physical mechanisms underlying these effects remain poorly understood. In this study, we investigated three flavonoids—apigenin, luteolin, and quercetin—applied to A. flavus NRRL 3357. We determined the following: (1) glycosylated luteolin led to a 10% reduction in maximum fungal growth capacity; (2) quercetin affected cell wall integrity by triggering extreme mycelial collapse, while apigenin and luteolin caused peeling of the outer layer of cell wall; (3) luteolin exhibited the highest antioxidant capacity in the environment compared to apigenin and quercetin; (4) osmotic stress assays did not reveal morphological defects; (5) flavonoids promoted cell adherence, a precursor for biofilm formation; and (6) RNA sequencing analysis revealed that flavonoids impact expression of putative cell wall and plasma membrane biosynthesis genes. Our findings suggest that the differential effects of quercetin, luteolin, and apigenin on membrane integrity and biofilm formation may be driven by their interactions with fungal cell walls. These insights may inform the development of novel antifungal additives or plant breeding strategies focusing on plant-derived compounds in crop protection.
Oral Care in Head and Neck Radiotherapy: Proposal for an Oral Hygiene Protocol
Authors: Spinato Giacomo , Schiavon Valentina , Torvilli Sara , Carraro Stefano , Amato Federica , Daloiso Antonio , Di Fiore Adolfo , Favero Vittorio , Franz Leonardo , Marioni Gino , de Filippis Cosimo , Fabbris Cristoforo , Emanuelli Enzo , Nicolai Piero
Published: September 2024

This review aims to provide a comprehensive overview of the literature on the oral side effects caused by radiotherapy for head and neck cancers. Various treatments are examined to mitigate these sequelae, and a protocol is proposed for dentists and dental hygienists to manage oncological patients. A literature search was conducted to select relevant articles addressing the effects of radiotherapy treatments on the oral cavity, with a particular focus on the development of mucositis, candidiasis, changes in salivary pH, trismus, fibrosis, and alterations in the oral biofilm. PubMed and MedLine were used as search engines, with keyword combinations including: head and neck cancer, mucositis, candida, dental care, dental hygiene, epidemiology, oral microbiome, biofilm, trismus, fibrosis, and salivary pH. A total of 226 articles were identified, spanning the period from 1998 to 2023. Articles deemed inappropriate or in languages other than English or Italian were excluded. A management protocol for oncological patients was proposed, divided into two phases: home-based and professional. Despite the advancements in intensity-modulated radiation therapy, it is impossible to completely avoid damage to healthy tissues. Preventive education and counseling in the dental chair, ongoing motivation, and education about oral hygiene are crucial to combine a good therapeutic outcome with an improved quality of life for the patient.
Evaluating the Feasibility of a Telescreening Program for Retinopathy of Prematurity (ROP) in Denmark
Authors: Al-Abaiji Hajer A. , Bangsgaard Regitze , Kofod Mads , Faber Carsten , Larsen Ann-Cathrine , Brost Agnes Galbo , Slidsborg Carina , Klemp Kristian , Breindahl Morten , la Cour Morten Dornonville de , Kessel Line
Published: September 2024

Objectives: This study investigates the feasibility of implementing telescreening for retinopathy of prematurity (ROP) using the ICON GO® widefield camera operated by a non-physician healthcare professional (NPHP). We hypothesized that images captured by an NPHP are adequate to evaluate ROP changes without further examinations. Secondly, the level of agreement between independent ROP graders were evaluated based on the fundus photographs. Methods: National ROP screening criteria were gestational age (GA) < 32 weeks or birthweight (BW) < 1500 g. Exclusion criteria were children hospitalized and born outside the Capital Region and examinations not performed by an NPHP. The screenings were performed using the ICON GO®. The NPHP selected the best images for evaluation by an on-site ophthalmologist, regarding whether re-examination was necessary and if so, whether the re-examination was beneficial. Lastly, the images were re-evaluated by an independent off-site ophthalmologist. Results: A total of 415 screening sessions on 165 patients performed by an NPHP were included. Re-examination was necessary in three screening sessions and beneficial in two. The level of agreement between the on-site and off-site ophthalmologists regarding ROP screening outcome was k = 0.82, ROP stage k = 0.69, plus disease k = 0.69, and lastly ROP zone k = 0.37. Of the screened children, ninety-seven (58.8%) had no ROP at any time points, sixty-two (37.6%) had some stage of ROP not requiring treatment, and six (3.6%) received ROP treatment. Conclusions: Telemedicine screening for ROP with the ICON GO® camera performed by an NPHP was feasible with an almost-perfect agreement and negligible need for re-examinations. The approach effectively identified children needing treatment, supporting the use of telescreening in ROP management.
Chest Tube Placement of Secondary Tracheoesophageal Voice Prosthesis: Overcoming Challenging Anatomy in the Laryngectomy Patient
Authors: Shires Courtney B. , Schertzer Joseph S. , Ottenstein Lauren , Harris Tricia , Sebelik Merry E.
Published: September 2024

Introduction: Total laryngectomy is used to cure advanced larynx cancer in many patients. The removal of the larynx requires the rehabilitation of the patient’s ability to communicate, and one common method is to place a tracheoesophageal voice prosthesis (TEP) as a secondary procedure after the patient has completed cancer treatment. The traditional technique utilizes a rigid esophagoscope for access, but this can prove difficult in many patients who have kyphosis, scarring of the neck, or trismus. We describe a technique to allow TEP placement in these challenging patients that does not utilize rigid esophagoscopy to access the tracheoesophageal puncture site. Methods: For more than 15 years, the senior authors of this study have used this technique in patients in whom traditional methods of TEP with rigid esophagoscope were unsuccessful or not attempted due to the anticipated high probability of failure. The ease of this technique has prompted its use for all patients undergoing secondary TEP placement in their practice. The technique is described in detail in the Methods section below. Results: The described method has been successfully utilized to place TEPs in many patients with challenging anatomy. There have been no failed placements, including a patient with severe trismus who was able to have a TEP placed by placing the chest tube and flexible endoscope transnasally. Further, because of precise visualization and ease of the technique, there have been no observed complications of injury to the pharyngoesophageal lumen or creation of a false passage. Conclusion: The use of a chest tube and flexible scope allows for the protection of the pharyngoesophageal lumen, precise visualization and placement of the puncture, and avoidance of a false tracheoesophageal passage, all while minimizing the need for extension of the patient’s neck. This has proven ideal for patients suffering the consequences of cancer treatment such as cervical scarring, fibrosis, kyphosis, and trismus.
The Effect of Student Loan Debt on Emergency Savings and the Moderating Role of Financial Knowledge: Evidence from the U.S. Survey of Household Economics and Decisionmaking
Authors: Korankye Thomas , Pearson Blain , Agyemang-Mintah Peter
Published: September 2024

This study examines data from the U.S. 2018 and 2019 Survey of Household Economics and Decision making (SHED) to understand the association between student loan debt and emergency-saving decisions, including the moderating role of financial knowledge. Controlling self-selection bias through a propensity score and coarsened exact matching approach, the findings reveal that individuals with student loan debt are less likely to save for financial emergencies. The findings also show that financial knowledge is positively associated with a higher likelihood of having emergency savings. Furthermore, the results from the moderating analysis indicate a statistically significant interaction effect. Based on the empirical results and the corresponding interaction plots, the findings suggest that targeted financial education may lead to improved financial outcomes for student loan borrowers, rather than assuming that such education occurred prior to a loan application.
Integrating Money Cycle Dynamics and Economocracy for Optimal Resource Allocation and Economic Stability
Authors: Challoumis Constantinos
Published: September 2024

This paper integrates two theoretical frameworks to explore optimal resource allocation and the dynamics of the money cycle in a hypothetical economy. It examined the theoretical background of the problems of choice. The first framework considers an economy governed by an omniscient authority responsible for production and distribution decisions, focusing on the logic of choice and efficient resource allocation. The second framework introduces the concept of the new economic system of Economocracy, emphasizing the role of the Money Cycle theory in economic management and governance. By combining these frameworks, the paper provides a comprehensive understanding of productive and distributive efficiency and examines the impact of the money cycle on economic stability and growth. A mathematical modeling of the money cycle is presented to highlight the relationship between money distribution, economic capacity, and overall economic health. The integrated approach offers valuable insights for optimizing resource allocation and enhancing economic resilience.
Assessing the Impact of the ECB’s Unconventional Monetary Policy on the European Stock Markets
Authors: Rincon Carlos J. , Petrova Anastasiia V.
Published: September 2024

This study assesses the effects of the European Central Bank’s (ECB) unconventional monetary policy (UMP) on the prices of selected European stock market indices during the European sovereign debt (2010–2012) and the COVID-19 pandemic (2020–2022) crises interventions. This research employs the instrumental variables (IV) two-stage least squares (2SLS) model approach to evaluate the effects of changes in the size of the ECB’s balance sheet on the pricing of key equity market indices in Europe. The results of this study suggest that the ECB’s asset value expansion had the opposite statistically significant effects on the European stock market indices’ prices between the interventions. That is, an increase in the ECB’s balance sheet size was associated with a decrease in the prices of the indices during the sovereign debt crisis and with a rise during the COVID-19 pandemic. This research pinpoints the price sensitivity of each of the European equity indices to the ECB’s UMP and determines the different outcomes of the ECB’s quantitative easing policy between the interventions.
RFSoC Softwarisation of a 2.45 GHz Doppler Microwave Radar Motion Sensor
Authors: Hobden Peter , Nurellari Edmond , Srivastava Saket
Published: September 2024

Microwave Doppler sensors are used extensively in motion detection as they are energy-efficient, small-size and relatively low-cost sensors. Common applications of microwave Doppler sensors are for detecting intrusion behind a car roof liner inside an automotive vehicle and to detect moving objects. These applications require a millisecond response from the target for effective detection. A Doppler microwave sensor is ideally suited to the task, as we are only interested in movement of a large water-based mass (i.e., a person) (FMCW Radar also detect static objects). Although microwave components at 2.45 GHz are now relatively cheap due to mass production of other Industrial Scientific and Medical application (ISM) devices, they do require tuning for temperature compensation, dielectric, and manufacturing variability. A digital solution would be ideal, as chip solutions are known to be more repeatable, but Application-Specific Integrated Circuits (ASICs) are expensive to initially prototype. This paper presents the first completely digital Doppler motion sensor solution at 2.45 GHz, implemented on the new RFSoC from Xilinx without the need to up/downconvert the frequency externally. Our proposed system uses a completely digital approach bringing the benefits of product repeatability, better overtemperature performance and softwarisation, without compromising any performance metric associated with a comparable analogue motion sensor. The RFSoC shows to give superior distance versus false detection, as the Signal-to-Noise Ratio (SNR) is better than a typical analogue system. This is mainly due to the high gain amplification requirement of an analogue system, making it susceptible to electrical noise appearing in the intermediate-frequency (IF) baseband. The proposed RFSoC-based Doppler sensor shows how digital technology can replace traditional analogue radio frequency (RF). A case study is presented showing how we can use a novel method of using multiple Doppler channels to provide range discrimination, which can be performed in both analogue and in a digital implementation (RFSoC).
Effect of Biochar on Composting of Cow Manure and Kitchen Waste
Authors: Sebahire Felicien , Faridullah Faridullah , Irshad Muhammad , Bacha Aziz Ur Rahim , Hafeez Farhan , Nduwamungu Jean
Published: September 2024

Composting is a common method for managing organic waste and creating nutrient-rich soil amendments. Recently, biochar, a carbon-rich material from biomass pyrolysis, has been noted for potentially improving composting. This study examines the impact of adding biochar to compost made from cow manure and kitchen waste through a controlled lab experiment. The treatments were labeled as CMX (cow manure), KWX (kitchen waste), and CMKWX (both) with X being the percentage of CM, KW, and CMKW minus that of biochar in the mixture. Key parameters such as temperature (T), pH, and electric conductivity (EC) were tracked during the composting processes, and the final composts were analyzed for total nitrogen (N), available nitrogen (AN), total phosphorus (TP), available phosphorus (AP), total potassium (TK), organic carbon (OC), calcium (Ca2+), magnesium (Mg2+), and organic matter (OM). The results showed that adding less than 10% biochar influenced composting positively. Specifically, 5% biochar amendment led to higher thermophilic temperatures (45–57 °C) and stable pH levels (6.3–8.7) compared to controls. However, biochar did not significantly enhance EC, which peaked at 1.78 dS/m in both the control and 5% biochar treatments. Nutrient analysis revealed that biochar increased Ca2+ (13.62 meq/g) and Mg2+ (5.73 meq/g) retention in CM composts (CM85 and CM100). The highest OM content was 16.84% in CM90, while the lowest was 3.81% in CM95. Higher OM negatively affected TN, with CM treatments having more OM and KW treatments having more TN. TP and TK were higher in control treatments without biochar. This study highlights the benefits of integrating biochar with organic waste for enhancing compost nutrient profiles and soil fertility. It was observed that the more diverse the compost feedstock, i.e., CMKW, the higher the nutrient content for treatments containing less than 10% biochar.
Combining Photovoltaics with the Rewetting of Peatlands—A SWOT Analysis of an Innovative Land Use for the Case of North-East Germany
Authors: Seidel Melissa , Wichmann Sabine , Pump Carl , Beckmann Volker
Published: September 2024

Reducing emissions from energy production and enhancing the capacity of land use systems to store carbon are both important pathways towards greenhouse gas neutrality. Expanding photovoltaics (PV) contributes to the former, while the rewetting of drained peatlands preserves the peat soil as long-term carbon store, thus contributing to the latter. However, both options are usually considered separately. This study analyses Peatland PV, defined as the combination of open-space PV with the rewetting of peatlands on the same site, and has an explorative and field-defining character. Due to a lack of empirical data, we used expert interviews to identify the strengths and weaknesses, opportunities, and threats of Peatland PV in the sparsely populated and peatland-rich state of Mecklenburg-Western Pomerania in North-East Germany. The material was analysed using a qualitative content analysis and compiled into SWOT and TOWS matrices. Besides the ecological and technological dimensions, this study focuses on the economic and legal framework in Germany. We found that Peatland PV may mitigate land use conflicts by contributing to climate and restoration targets, energy self-sufficiency, and security. Continued value creation can incentivize landowners to agree to peatland rewetting. Technical feasibility has, however, a significant influence on the profitability and thus the prospects of Peatland PV. Although Peatland PV has recently been included in the Renewable Energy Sources Act (EEG), several specialised legal regulations still need to be adapted to ensure legal certainty for all stakeholders. Pilot implementation projects are required to study effects on vegetation cover, soil, peatland ecosystem services, biodiversity, hydrology, and water management, as well as to analyse the feasibility and profitability of Peatland PV.
The Association between Food Groups, Nutraceuticals, and Food Supplements Consumption on Vascular Health Outcomes: A Literature Review
Authors: Theodoridis Xenophon , Chourdakis Michail , Papaemmanouil Androniki , Chaloulakou Stavroula , Papageorgiou Niki , Georgakou Athina Vasiliki , Chatzis Georgios , Triantafyllou Areti
Published: September 2024

Vascular aging, marked by alterations in the structure and function of blood vessels, including heightened arterial stiffness and impaired endothelial function, is linked to a higher likelihood of developing cardiovascular and age-associated pathological conditions. Oxidative stress and inflammation are key stimulation factors in vascular aging. Engaging in healthy dietary habits could enhance the functioning of blood vessels. The aim of this study was to conduct a literature review of the evidence regarding the relationship between food regimens, nutraceuticals, and dietary supplements and vascular health. A search of electronic databases, including PubMed, Scopus, and Web of Science Core Collection, was performed. Experimental and observational studies evaluating the association between food groups, nutraceuticals, supplements, and endothelial function and/or arterial stiffness were deemed eligible for this narrative review. Based on the current body of the included studies, food groups, nutraceuticals, and dietary supplements may not demonstrate superiority over placebos in enhancing markers of vascular health. To obtain more reliable evidence on the effectiveness of interventions in vascular health, additional RCTs with larger sample sizes, extended follow-up periods, and multi-center participation are necessary. Enhancing the credibility of these RCTs requires better control of dietary variables and more precise measurement of vascular health markers.
The Potential of JWH-133 to Inhibit the TLR4/NF-κB Signaling Pathway in Uterine Ischemia–Reperfusion Injury
Authors: Inandiklioglu Nihal , Onat Taylan , Raheem Kayode Yomi , Kaya Savas
Published: September 2024

In recent years, significant progress has been made in understanding the biological and molecular pathways that regulate the effects of ischemia–reperfusion (I/R) injuries. However, despite these developments, various pharmacological agents are still being tested to either protect against or mitigate the damage caused by the IR’s harmful consequences. JWH133 is a CB2R-selective agonist and belongs to the class of Δ8-tetrahydrocannabinol. The present study aimed to determine the in vivo effect of JWH-133 on uterine IR injury via the TLR4/NF-κB, pathway. Female Wistar albino rats (n = 40) were randomly divided into five groups. Three different doses of JWH-133 (0.2, 1, and 5 mg/kg) were administered to the rats. RNA was isolated from uterine tissue samples, and gene expression was measured by RT-PCR using specific primers. The interaction energies and binding affinities of JWH-133 with IL-1β, IL-6, NF-κB, TLR-4, and TNF-α were calculated through molecular docking analysis. The expression analysis revealed that JWH-133 administration significantly reduced the expression levels of IL-1β, IL-6, NF-κB, TLR-4, and TNF-α (p < 0.05). Notably, in the 1 mg/kg JWH-133 group, all of the gene expression levels decreased significantly (p < 0.05). The molecular docking results showed that JWH-133 formed hydrogen bonds with GLU64 of IL-1β, SER226 of IL-6, and SER62 of TNF-α. This study highlights the molecular binding affinity of JWH-133 and its potential effects on inflammation in IR injury. These results pave the way for future research on its potential as a therapeutic target.
Ethnobotanical Surveys of Plants Used by Quilombola Communities in Brazil: A Scoping Review
Authors: Ramos Letícia Francine Silva , de Sousa Ananda Gomes , de Siqueira Amorim Rebeca , de Araújo Roque Alan , Carvalho Israel Luís Diniz , de Carvalho Ana Laura Vilela , Santos Milena Evangelista dos , Marques Maiara Bernardes , de Lima Luiza Rayanna Amorim , Costa Moan Jéfter Fernandes , Sette-de-Souza Pedro Henrique
Published: September 2024

Quilombola communities play a crucial role in maintaining biodiversity through traditional management models. The use of medicinal plants within these communities reflects a deep reservoir of knowledge, passed down through generations. The objective of this study was to conduct a scoping review to systematically analyze and synthesize the existing literature on the medicinal plants used by Quilombola communities in Brazil, with a focus on their therapeutic applications and cultural significance. The Population, Concept, and Context (PCC) strategy was utilized, where the population refers to the Quilombolas, the concept pertains to medicinal plants, and the context involves illness. A total of 888 studies were initially identified, but only 10 met the inclusion criteria, covering 297 plant species from 80 different families. These plants are employed in a wide range of therapeutic applications, with decoction, alcohol maceration, and infusion being the most common methods of preparation. The study highlights the rich ethnopharmacological knowledge held by Quilombola communities and underscores the need for greater recognition and integration of this traditional knowledge into public health practices. The conclusion emphasizes the importance of preserving and validating the use of medicinal plants by these communities, which could serve as a foundation for future pharmacological discoveries and the development of culturally appropriate health interventions.
Association of Loneliness with Functional and Cognitive Status in Minor and Major Neurocognitive Disorders
Authors: Moretti Maria Claudia , Bonfitto Iris , Nieddu Luciano , Leccisotti Ivana , Dimalta Savino , Moniello Giovanni , Lozupone Madia , Bellomo Antonello , Panza Francesco , Avolio Carlo , Altamura Mario
Published: September 2024

Background: Neurocognitive disorders (NCDs) have a variable decline in cognitive function, while loneliness was associated with cognitive impairment and increased dementia risk. In the present study, we examined the associations of loneliness with functional and cognitive status in patients with minor (mild cognitive impairment) and major NCDs (dementia). Methods: We diagnosed mild NCD (n = 42) and major NCD (n = 164) through DSM-5 criteria on 206 participants aged > 65 years using the UCLA 3-Item Loneliness Scale (UCLA-3) to evaluate loneliness, the activities of daily living (ADL) and the instrumental activities of daily living (IADL) scales to measure functional status, and Mini-Mental State Examination (MMSE) to assess cognitive functions. Results: In a multivariate regression model, the effect of loneliness on cognitive functions was negative in major (β = −1.05, p < 0.0001) and minor NCD (β = −0.06, p < 0.01). In the fully adjusted multivariate regression model (sex–age–education–multimorbidity–depressive symptoms–antidementia drug treatment), the effect of loneliness remained negative for major NCD and became positive for minor NCD (β = 0.09, p < 0.001). The effect of loneliness on IADL (β = −0.26, p < 0.0001) and ADL (β = −0.24, p < 0.001) showed a negative effect for major NCD across the different models, while for minor NCD, the effect was positive (IADL: β = 0.26, p < 0.0001; ADL: β = 0.05, p = 0.01). Minor NCD displayed different levels of MMSE (β = 6.68, p < 0.001) but not ADL or IADL, compared to major NCD for the same levels of loneliness. MANOVA pill test suggested a statistically significant and different interactive effect of loneliness on functional and cognitive variables between minor and major NCDs. Conclusions: We confirmed the relationships between loneliness and cognitive and functional status in major NCD, observing a novel trend in minor NCD.
Immunogenicity of Botulinum Toxin Type A in Different Clinical and Cosmetic Treatment, a Literature Review
Authors: Lee Kar Wai Alvin , Chan Lisa Kwin Wah , Lee Angela Wai Kay , Lee Cheuk Hung , Wan Jovian , Yi Kyu-Ho
Published: September 2024

Background: Botulinum toxin type A is widely utilized for both therapeutic and aesthetic purposes, yet concerns regarding its immunogenicity have raised issues related to treatment failure and adverse reactions. Objective: This review aims to evaluate the immunogenicity of commercially available botulinum toxin type A products across various clinical indications and identify the risk factors associated with antibody formation. Methods: A comprehensive search of electronic databases was conducted to find studies that investigated the immunogenicity of botulinum toxin type A in patients treated for different conditions. The studies were classified based on the Oxford Center for Evidence-Based Medicine’s evidence hierarchy. Results: The overall incidence of neutralizing antibody formation with botulinum toxin type A treatment is relatively low. However, it varies depending on the indication and is influenced by factors such as the frequency of injections and the cumulative dose. The total cumulative dose and the number of treatment cycles are critical factors in determining the risk of developing antibodies against botulinum toxin type A. Conclusion: This literature review highlights that the immunogenicity of botulinum toxin type A products differs across indications, with repeated injections posing a significant risk for the formation of neutralizing antibodies. The findings underscore the need for further research to better understand antibody formation mechanisms and to develop strategies that minimize their impact on treatment efficacy.
The Gut Microbiota Impacts Gastrointestinal Cancers through Obesity, Diabetes, and Chronic Inflammation
Authors: Rumyantsev Konstantin A. , Polyakova Vera V. , Sorokina Irina V. , Feoktistova Polina S. , Khatkov Igor E. , Bodunova Natalia A. , Zhukova Lyudmila G.
Published: September 2024

The gut microbiota’s pivotal role in human health is increasingly evident, particularly in chronic conditions like obesity, diabetes, and inflammatory diseases. This intricate symbiotic relationship influences metabolic balance and immune responses. Notably, gut microbial dysbiosis is linked to obesity’s metabolic disruption and chronic low-grade inflammation. Similarly, in diabetes, the microbiota’s impact on insulin resistance and glucose metabolism is becoming evident. Chronic inflammation, a common denominator in these conditions, is also a recognized precursor to carcinogenesis. This intersection prompts a compelling question: does the gut microbiota’s influence extend to gastrointestinal cancers like colorectal and pancreatic cancer? These malignancies are closely intertwined with inflammation and metabolic dysregulation. Exploring whether the microbial signatures associated with chronic conditions overlap with precancerous or cancerous states offers new perspectives. This article reviews emerging evidence on the interplay between the gut microbiota, chronic conditions, and gastrointestinal cancers. By elucidating these connections, we aim to uncover potential avenues for innovative diagnostic, preventative, and therapeutic strategies in colorectal and pancreatic cancer management.
Valorization of Iron (II) Oxalate Dihydrate Coming from Pickling Processes through Thermal Conversion
Authors: Salucci Emiliano , D’Angelo Antonio , Fabozzi Antonio , Senneca Osvalda , Bellucci Francesco , Francesca Rosa , Grénman Henrik , Saxen Henrik , Di Serio Martino , Russo Vincenzo
Published: September 2024

The valorization of industrial byproducts is an emerging practice that aims to transform waste materials generated during production processes into valuable resources. In this work, a preliminary study was carried out on the thermal conversion of an industrial solid byproduct resulting from the pickling of metal surfaces, mainly containing iron (II) oxalate. In a fixed-bed reactor, the thermal conversion was investigated as a function of the operating temperature and overall time. The starting material and the products obtained after heat treatment were characterized in detail, using numerous qualitative and semi-quantitative techniques. The aim of this research was to determine the optimal operating conditions for the transformation of the industrial byproduct into a high-quality product. By varying the operating conditions, it was found that complete conversion of iron (II) oxalate to magnetite was achieved at high temperatures (i.e., 773 K and 873 K) after one hour of treatment. The resulting product had a low degree of crystallization, which increased slightly with an increasing reaction time at a temperature of 873 K, reaching a maximum of about 11%. The magnetite obtained can be used in the future as a starting material for chemical looping processes as a chemical/energy carrier for the production of hydrogen.
Melt Pool Changes Characterization in Laser-Processed H11 Hot Work Tool Steel Using Point-by-Point Scanning Mode towards LPBF Process Optimization
Authors: Fryzowicz Krzysztof , Bardo Radosław , Dziurka Rafał , Kawałko Jakub , Cios Grzegorz , Stwora Andrzej , Bała Piotr
Published: September 2024

Additive manufacturing techniques employing laser-based metal melting have garnered significant attention within the scientific community. Despite a decade of comprehensive research on the fundamentals of these techniques, there still remain unexplored facets related to heat flux impact on metallic alloys’ properties. Particularly, the effects of point-by-point laser operation on melt pool formation in metallic materials still remain unclear. Thus, this study focuses on the implications of laser metal melting, particularly investigating a point-by-point laser mode operation’s influence on melt pool formation and its geometry in the phase-transformation-sensitive material H11 hot work tool steel. To examine the melt pool, singular laser tracks with various laser parameters were scanned across H11 sheet metal, which allowed for the elimination of layer-by-layer heat cycles’ influence on the melt pool’s microstructure. Samples were examined by means of metallography, revealing significant differences in the melt pool’s depth, influenced mostly by exposure time rather than volumetric energy density. Heat-affected zone effects were found to have a limited range and thus potentially marginal effects in layer-by-layer manufacturing conditions. At the same time, retained austenite concentrations near fusion lines have been found within melt pools, suggesting potential micro-segregation of the alloying additions. The results present guidelines towards laser melting processes optimization.
Hierarchically Graphitic Carbon Structure Derived from Metal Ions Impregnated Harmful Inedible Seaweed as Energy-Related Material
Authors: Song Yun-Mi , Park Hui Gyeong , Lee Jung-Soo
Published: September 2024

This study explored the development of hierarchical graphitic carbon structures (HGCs) from harmful inedible seaweed waste harvested in the summer. Elevated sea temperatures during the summer increase the cellulose content of seaweeds, making them unsuitable for consumption. By utilizing seaweed biomass, this study addresses critical marine environmental issues and provides a sustainable solution for promising electrode materials for energy storage devices. The fabrication process involved impregnating seaweed with Ni ions, followed by annealing to create a highly crystalline carbon structure. Subsequent etching produced numerous nano-sized pores and a large surface area (806 m2/g), significantly enhancing the number of electrically active sites. The resulting HGCs exhibited a high capacitance and maintained their capacity even after 10,000 cycles in fast-current systems. This innovative approach not only mitigates the environmental burden of seaweed waste but also offers a sustainable method for converting it into efficient energy storage materials.
Comparison of Fracture Strength of Milled and 3D-Printed Crown Materials According to Occlusal Thickness
Authors: Park Yeseul , Kim Jimin , Kang You-Jung , Shim Eun-Young , Kim Jee-Hwan
Published: September 2024

This study aimed to measure the fracture strengths and hardness of final restorative milled and 3D-printed materials and evaluate the appropriate crown thickness for their clinical use for permanent prosthesis. One type of milled material (group M) and two types of 3D-printed materials (groups P1 and P2) were used. Their crown thickness was set to 0.5, 1.0, and 1.5 mm for each group, and the fracture strength was measured. Vickers hardness was measured and analyzed to confirm the hardness of each material. Scanning electron microscopy was taken to observe the surface changes of the 3D-printed materials under loads of 900 and 1500 N. With increased thickness, the fracture strength significantly increased for group M but significantly decreased for group P1. For group P2, the fracture strengths for the thicknesses of 0.5 mm and 1.5 mm significantly differed, but that for 1.0 mm did not differ from those for other thicknesses. The hardness of group M was significantly higher than that of groups P1 and P2. For all thicknesses, the fracture strength was higher than the average occlusal force for all materials; however, an appropriate crown thickness is required depending on the material and component.
Microwave Hybrid Sintering and Soldering of Cu-Cr-W Composite Material for Reactive Power Breakers
Authors: Savu Sorin Vasile , Ghelsingher Cristian Daniel , Ștefan Iulian , Sîrbu Nicușor-Alin , Midan Andrei-Angelo , Dumitru Ilie , Savu Ionel Dănuț , Nicolicescu Claudiu , David Andrej
Published: September 2024

Over 60% of reported failures for reactive power compensation systems are given for damage to electrical circuit breaker contacts. This paper presents a study on the development of microwave technology for sintering of W–Cu–Cr alloys at 1012 °C for 65 min using 623.38 W microwave power, as well as microwave joining at 231 °C of the W–Cu–Cr composite material on body contact using 475 W microwave power for 55 s. The joined components were subjected to mechanical and electrical tests in accordance with ICE standards to validate the applied technology. Tests of connection–disconnection of the electrical contacts were carried out in accordance with the maximum number of disconnections allowed by the manufacturer (2 cycles/min): 25 s rest time and 5 s operating time under load. The components of the electrical contact after 111237 switches were analyzed under a microscope revealing a reduction of the damaged area by 27% compared with the original contact.
Influence of Plant Additives on Antimicrobial Properties of Glass-Fabric-Reinforced Epoxy Composites Used in Railway Transport
Authors: Węgier Aleksandra , Kaźmierczyk Filip , Efenberger-Szmechtyk Magdalena , Rosiak Angelina , Kałużna-Czaplińska Joanna , Masek Anna
Published: September 2024

The aim of this research was to explore the innovative use of natural additives, containing phytochemicals with proven antimicrobial effects, in the production of epoxy–glass composites. This study was based on information regarding the antimicrobial effects of phytochemicals present in Cistus incanus, Zingiber officinale, and Armoracia rusticana. The additives were subjected to a gas chromatography (GC) analysis to determine their composition, and, subsequently, they were used to prepare resin mixtures and to produce epoxy–glass composites. Samples of the modified materials were tested against E. coli, S. aureus, and C. albicans. In addition, flammability and durability tests were also performed. It was found that the strongest biocidal properties were demonstrated by the material with the addition of cistus, which caused a reduction of microorganisms by 2.13 log units (S. aureus), 1.51 log units (E. coli), and 0.81 log units (C. albicans). The same material also achieved the most favorable results of strength tests, with the values of flexural strength and tensile strength reaching 390 MPa and 280 MPa, respectively. Public transport is a place particularly exposed to various types of pathogens. Currently, there are no solutions on the railway market that involve the use of composites modified in this respect.
Design of CO2-Resistant High-Entropy Perovskites Based on Ba0.5Sr0.5Co0.8Fe0.2O3-δ Materials
Authors: Zhu Yongfan , Liu Jia , Liu Zhengkun , Liu Gongping , Jin Wanqin
Published: September 2024

High-entropy perovskite materials (HEPMs), characterized by their multi-element composition and highly disordered structure, can incorporate multiple rare earth elements at the A-site, producing perovskites with enhanced CO2 resistance, making them stay high performance and structurally stable in the CO2 atmosphere. However, this modification may result in reduced oxygen permeability. In this study, we investigated La0.2Pr0.2Nd0.2Ba0.2Sr0.2Co0.8Fe0.2O3-δ (L0.2M1.8) high-entropy perovskite materials, focusing on enhancing their oxygen permeability in both air and CO2 atmospheres through strategic design modifications at the B-sites and A/B-sites. We prepared Ni-substituted La0.2Pr0.2Nd0.2Ba0.2Sr0.2Co0.7Fe0.2Ni0.1O3-δ (L0.2M1.7N0.1) HEPMs by introducing Ni elements at the B-site, and further innovatively introduced A-site defects to prepare La0.2Pr0.2Nd0.2Ba0.2Sr0.2Co0.7Fe0.2Ni0.1O3-δ (L0.1M1.7N0.1) materials. In a pure CO2 atmosphere, the oxygen permeation flux of the L0.1M1.7N0.1 membrane can reach 0.29 mL·cm−2·min−1. Notably, the L0.1M1.7N0.1 membrane maintained a good perovskite structure after stability tests extending up to 120 h under 20% CO2/80% He atmosphere. These findings suggest that A-site-defect high-entropy perovskites hold great promise for applications in CO2 capture, storage, and utilization.
Wettability and Interfacial Reaction between the K492M Alloy and an Al2O3 Shell
Authors: Chen Guangyao , Liao Houjin , Deng Shaowen , Zhang Man , Cai Zheyu , Xu Hui , Wang Enhui , Hou Xinmei , Li Chonghe
Published: September 2024

In this study, wettability behavior and the interaction between the K492M alloy and an Al2O3 shell were investigated at 1430 °C for 2~5 min. The microstructural characterization of the alloy–shell interface was carried out by optical microscopy (OM) and scanning electron microscopy (SEM). The results indicated that the interaction could cause a sand adhesion phenomenon affecting the alloy, and the attached products were Al2O3 particles. In addition, the wetting angles of the alloys located on the shell were 125.2°, 109.4°, 97.0°, and 95.0°, respectively, as the contact time was increased from 2 to 5 min. Apparently, the wettability of the alloy in relation to the shell had a relationship with the contact time, where a longer contact time was beneficial to the permeation of the alloy into the shell and the interaction between the two components. No significant chemical products could be detected in the interaction layer, indicating that only the occurrence of the physical dissolution of the shell took place in the alloy melt.
Analysis of Ni-Cu Interaction in Aluminum-Based Alloys: Hardness, Tensile and Precipitation Behavior
Authors: Samuel Ehab , Samuel Agnes M. , Songmene Victor , Doty Herbert W. , Samuel Fawzy H.
Published: September 2024

The present work was aimed at quantifying the effects of Ni addition in the range of 0–4% together with 0.3%Zr on the hardness and the tensile properties, volume fraction of intermetallics, and changes in size and distribution of phase precipitation in Sr-modified Al-9%Si-2%Cu-0.6%Mg cast alloys. The study was mainly carried out using high-resolution FESEM and TEM microscopes equipped with EDS facilities. Samples were solidified at the rate of ~3 °C/s and examined at different aging conditions. The investigations are supported by thermal analysis carried out at a solidification rate of ~0.8 °C/s. The results revealed that the main compositions of the Ni-based phases are close to Al3(Ni,Cu), Al3CuNi, and Al3Ni. An Al3Ni2Cu2 phase was also detected in the 4%Ni alloy. The Cu–Ni phases were observed to precipitate, covering the surfaces of pre-existing primary Al3Zr particles. The TEM analysis indicated the magnitude of the reduction in both size and density of the precipitated Al2Cu phase particles as the Ni content reached 4%, coupled with a delay in the transition from coherent to incoherency of the Al2Cu precipitates.
Impacts of Waste Rubber Products on the Structure and Properties of Modified Asphalt Binder: Part I—Crumb Rubber
Authors: Obukhova Svetlana , Budkina Angelina , Korolev Evgeniy , Gladkikh Vitaliy
Published: September 2024

The issue of forming a reliable and sustainable structure of crumb-rubber-modified binder is an important scientific and technical task. The quality of this task will increase the technical and economic efficiencies of road construction materials. This work is dedicated to developing a scientifically justified method of directed thermomechanical devulcanization, which ensures the solubility of the crumb rubber in the complex structure of a polydisperse composite material, preventing the formation of aggregates consisting of unsaturated crumb rubber particles, whose elastic aftereffect causes intensive cracking, especially during low-temperature road operations. The novelty in the first part of this article is due to the fact that, for the first time, the quantitative ratio of the polymer component in the crumb rubber was experimentally determined. The ratio of the polymer component to the total content of the other rubber components in the crumb rubber (CR) was determined to be, on average, 93.3 ± 1.8%. The stabilities of the compositions of crumb rubber from different batches were experimentally studied. The nature of the polymer component in the crumb rubber was determined. A hypothesis was formulated to obtain a thermodynamically stable and sustainable binder modified with crumb rubber. To evaluate the compatibility of hydrocarbon plasticizers with the studied CR samples, the following semi-empirical and thermodynamic compatibility parameters were calculated: Hildebrand solubility parameters based on evaporation energy and surface tension, Barstein’s compatibility parameter |X|, Traxler coefficient, and the mass ratio of paraffin naphthene:asphaltenes. It was shown that for the substances under study, it is advisable to justify the choice of plasticizer based on chemical compatibility criteria. It was established that a supramolecular plasticization mechanism occurs in the “hydrocarbon plasticizer–crumb rubber” systems under consideration. In the development of the crumb-rubber-modified binder, it was found that the use of activated crumb rubber (ACR) from large tires does not ensure the achievement of a stable and resilient structure of the crumb-rubber-modified bitumen.
Advances in Resistance Welding of Fiber-Reinforced Thermoplastics
Authors: Geng Zhanyi , Yu Shibao , Wang Shiyuan , Tian Zengtai , Gao Zhonglin , Wang Kaifeng , Li Yang
Published: September 2024

Fiber-reinforced thermoplastics (FRTPs) have become a new generation of lightweight materials due to their superior mechanical properties, good weldability and environmental resistance, potential for recycling, etc. The market for FRTPs is expected to grow at a compound annual growth rate (CAGR) of 7.8% from 2022 to 2030. Many researchers have been trying to solve the problems in their processing and joining process, and gradually expand their application. Resistance welding is one of the most suitable techniques to join FRTPs. This paper summarizes the research progress of FRTP resistance welding in terms of the basic process of FRTP resistance welding, factors affecting joint performance, joint failure behavior, numerical simulation, weld quality control, and resistance welding of thermoplastic/thermoset composites. The objective of this paper is to provide a deeper insight into the knowledge of FRTP resistance welding and provide reference for the further development and application of FRTP resistance welding.
An Automatic Vehicle Navigation System Based on Filters Integrating Inertial Navigation and Global Positioning Systems
Authors: Xu Haizhu , Geng Duanyang , Fan Zhixian , Wu Dexi , Chen Meizhou
Published: September 2024

The key technologies for advanced autonomous vehicles include those relating to perception, decision making, and execution. Path-tracking control in autonomous vehicles is heavily dependent on their positioning system. Therefore, the development of low-cost and reliable positioning systems is crucial to improving perception and decision-making technologies for autonomous vehicles. Although the accuracy of the global positioning system (GPS) is extremely high, it is vulnerable to interference. Further, despite the low positioning accuracy of inertial navigation systems (INSs), their robustness is notably high. Therefore, an integrated navigation information method based on the Adaptive Particle Filter and the Iterative Kalman Filter (APF-IKF) was developed in this study. Firstly, an integrated navigation system model was established. Then, the IKF was adopted to estimate the speed, latitude and longitude errors of the INS. Thirdly, the newest estimated error results were introduced into the APF to optimize the distribution function, and the particle quality was improved. In this process, the APF can filter non-Gaussian noise, preliminarily estimate the error, optimize the result with the IKF and correct the output information of the INS with the final estimated error. Finally, by using differential GPS positioning as the benchmark, we built a real-vehicle test platform with a low-cost and low-precision GPS and inertial units and carried out a series of real-vehicle tests. The experimental results show that compared with the traditional KF method, APF-IKF can significantly improve the positioning accuracy and robustness of the system.