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J, Volume 7, Issue 4 (December 2024) – 12 articles

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8 pages, 3507 KiB  
Article
Fructose-Derived Carbon Dots as Selective Antitumor Agents in Breast Cancer Therapy: Synthesis, Characterization, and Biological Evaluation
by Sofia Magalhães, Carla Luís and Abel Duarte
J 2024, 7(4), 584-591; https://doi.org/10.3390/j7040035 - 22 Dec 2024
Viewed by 584
Abstract
This study explored a novel method using fructose-derived carbon dots (FCDs) for antitumor therapy in breast cancer (BC), marking a pioneering use of fructose as a carbon source for nanoparticle synthesis. BC, known for its complexity and heterogeneity, was chosen as a model [...] Read more.
This study explored a novel method using fructose-derived carbon dots (FCDs) for antitumor therapy in breast cancer (BC), marking a pioneering use of fructose as a carbon source for nanoparticle synthesis. BC, known for its complexity and heterogeneity, was chosen as a model due to its increasing mortality and incidence rates. The FCD synthesis involved the decomposition of fructose through microwave irradiation, followed by purification and characterization using techniques such as transmission electron microscopy, dynamic light scattering, fluorescence spectrophotometry, and Fourier-transform infrared spectroscopy. The FCDs, ranging in size from 2 to 6 nm, presented a hydrodynamic diameter below 2 nm, a spherical morphology, and a crystalline structure. As expected, FCDs were composed by carbon, oxygen, and hydrogen, and exhibited fluorescence with absorption and emission spectra at 405 nm and around 520 nm, respectively. Cell-based assays on breast epithelial and tumor cell lines demonstrated a dose-dependent response, with a decreased viability rate more pronounced in breast tumor cells. In conclusion, FCDs showed significant potential as selective antitumor agents for breast cancer therapy. The comprehensive characterization and cell-based assay evaluations provided valuable insights into the applications of these nanoparticles in breast cancer treatment, highlighting their selective toxicity and impact on tumor cells. Full article
(This article belongs to the Section Biology & Life Sciences)
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13 pages, 1625 KiB  
Article
Investigating the Iron Plating and Stripping of Anolytes for All-Iron Redox-Flow Batteries
by Marius Engler, Michael Stich, Christoph Baumer and Andreas Bund
J 2024, 7(4), 571-583; https://doi.org/10.3390/j7040034 - 11 Dec 2024
Viewed by 718
Abstract
All-iron redox-flow batteries (AIRFB) are capable of addressing the needs for cost-effective long-term storage of renewable energies. Currently, a major limitation of AIRFB performance is the half-cell reaction of the anolyte utilising the redox couple Fe/Fe2+. In this work, the performance [...] Read more.
All-iron redox-flow batteries (AIRFB) are capable of addressing the needs for cost-effective long-term storage of renewable energies. Currently, a major limitation of AIRFB performance is the half-cell reaction of the anolyte utilising the redox couple Fe/Fe2+. In this work, the performance of sulphate and chloride-based iron electrolytes was investigated by combining cyclic voltammetry (CV) and electrochemical quartz crystal microbalance (EQCM). The investigations demonstrate that complexing agents exert a detrimental influence on the kinetics of plating/stripping reactions, resulting in diffusivity reduction, while favouring hydrogen evolution reaction (HER). The coulombic (plating) efficiency was found to be 87.1% at −1.2 V vs. Ag/AgCl (sat’d) at pH 3.5, while the coulombic efficiency in oxidation sweep (stripping) was observed to be 100% in an electrolyte containing 0.8 M FeCl2 and 3 M NH4Cl. In the context of iron deposition, the most crucial factors are the suppression of HER, and the influence of diffusion limitations, as well as the role of additives in this process to achieve a high reversibility. It is evident that the investigated complexing agents of glycine, malic acid and malonic acid are inadequate for battery-compatible, efficient properties, given that the overvoltages for the charge transfer reaction are too high and parasitic HER reduces coulombic efficiencies. Ultimately, the choice of deposition parameters from EQCM and electrolyte composition reduced to 0.8 M FeCl2, and 3 M NH4Cl can optimise the battery efficiencies as such. Full article
(This article belongs to the Section Chemistry & Material Sciences)
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25 pages, 1176 KiB  
Review
Hydrogen as an Energy Carrier—An Overview over Technology, Status, and Challenges in Germany
by Caroline Willich
J 2024, 7(4), 546-570; https://doi.org/10.3390/j7040033 - 2 Dec 2024
Viewed by 1297
Abstract
Hydrogen is set to become an important energy carrier in Germany in the next decades in the country’s quest to reach the target of climate neutrality by 2045. To meet Germany’s potential green hydrogen demand of up to 587 to 1143 TWh by [...] Read more.
Hydrogen is set to become an important energy carrier in Germany in the next decades in the country’s quest to reach the target of climate neutrality by 2045. To meet Germany’s potential green hydrogen demand of up to 587 to 1143 TWh by 2045, electrolyser capacities between 7 and 71 GW by 2030 and between 137 to 275 GW by 2050 are required. Presently, the capacities for electrolysis are small (around 153 MW), and even with an increase in electrolysis capacity of >1 GW per year, Germany will still need to import large quantities of hydrogen to meet its future demand. This work examines the expected green hydrogen demand in different sectors, describes the available technologies, and highlights the current situation and challenges that need to be addressed in the next years to reach Germany’s climate goals, with regard to scaling up production, infrastructure development, and transport as well as developing the demand for green hydrogen. Full article
(This article belongs to the Section Engineering)
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17 pages, 1779 KiB  
Article
Multicomponent Stress–Strength Reliability with Extreme Value Distribution Margins: Its Theory and Application to Hydrological Data
by Rebeca Klamerick Lima, Felipe Sousa Quintino, Melquisadec Oliveira, Luan Carlos de Sena Monteiro Ozelim, Tiago A. da Fonseca and Pushpa Narayan Rathie
J 2024, 7(4), 529-545; https://doi.org/10.3390/j7040032 - 1 Dec 2024
Viewed by 767
Abstract
This paper focuses on the estimation of multicomponent stress–strength models, an important concept in reliability analyses used to determine the probability that a system will function successfully under varying stress conditions. Understanding and accurately estimating these probabilities is essential in fields such as [...] Read more.
This paper focuses on the estimation of multicomponent stress–strength models, an important concept in reliability analyses used to determine the probability that a system will function successfully under varying stress conditions. Understanding and accurately estimating these probabilities is essential in fields such as engineering and risk management, where the reliability of components under extreme conditions can have significant consequences. This is the case in applications where one seeks to model extreme hydrological events. Specifically, this study examines cases where the random variables X (representing strength) and Y (representing stress) follow extreme value distributions. New analytical expressions are derived for multicomponent stress–strength reliability (MSSR) when different classes of extreme distributions are considered, using the extreme value H-function. These results are applied to three l-max stable laws and six p-max stable laws, providing a robust theoretical framework for multicomponent stress–strength analyses under extreme conditions. To demonstrate the practical relevance of the proposed models, a real dataset is analyzed, focusing on the monthly water capacity of the Shasta Reservoir in California (USA) during August and December from 1980 to 2015. This application showcases the effectiveness of the derived expressions in modeling real-world data. Full article
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27 pages, 8610 KiB  
Article
A Fuzzy Spatial Multiple Criteria Analysis Methodology for Solid Waste Landfill Siting
by Themistoklis D. Kontos and Yiannis G. Zevgolis
J 2024, 7(4), 502-528; https://doi.org/10.3390/j7040031 - 25 Nov 2024
Viewed by 1061
Abstract
The process of siting municipal solid waste landfills in Greece faces significant challenges due to land resource limitations, the country’s mountainous and water-permeable terrain, and strong public opposition. This study introduces a novel methodology for optimizing landfill sites on Lemnos Island in the [...] Read more.
The process of siting municipal solid waste landfills in Greece faces significant challenges due to land resource limitations, the country’s mountainous and water-permeable terrain, and strong public opposition. This study introduces a novel methodology for optimizing landfill sites on Lemnos Island in the North Aegean Sea using a Fuzzy Spatial Multiple Criteria Analysis (FSMCA) approach. By combining fuzzy sets theory, Geographic Information Systems (GIS), Analytic Hierarchy Process (AHP), spatial autocorrelation, spatial clustering and sensitivity analysis, this methodology addresses the uncertainties and complexities inherent in landfill siting. The decision problem is structured hierarchically into five levels to manage multiple criteria effectively. Criteria weights are determined using AHP, with discrete criteria graded according to Greek and EU guidelines, and continuous criteria evaluated through fuzzy sets theory. The region’s suitability is assessed using multiple criteria analysis, revealing that 9.7% of Lemnos Island is appropriate for landfill placement. Sensitivity analysis confirms the robustness of the methodology to changes in criteria weights. The case study demonstrates the practical application and benefits of FSMCA in a real-world scenario, underscoring its potential to improve sustainable waste management practices and inform policy making. Full article
(This article belongs to the Section Environmental Sciences)
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13 pages, 1420 KiB  
Review
Inflammatory Bowel Diseases in Spain: A View from the Present to the Future
by Raquel Francés, Yuanji Fu, Christophe Desterke and Jorge Mata-Garrido
J 2024, 7(4), 489-501; https://doi.org/10.3390/j7040030 - 14 Nov 2024
Viewed by 827
Abstract
Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, presents a growing health challenge in Spain. This review examines the current understanding of IBD through the lens of genetics, epigenetics, and metabolism, offering insights into future directions for research and clinical management. [...] Read more.
Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, presents a growing health challenge in Spain. This review examines the current understanding of IBD through the lens of genetics, epigenetics, and metabolism, offering insights into future directions for research and clinical management. Recent advancements in genetic studies have identified numerous susceptibility loci, highlighting the complex interplay between genetic predisposition and environmental triggers. Epigenetic modifications, including DNA methylation and histone modification, further elucidate the pathogenesis of IBD, underscoring the role of gene–environment interactions. Metabolic alterations, particularly in the gut microbiome, emerge as crucial factors influencing disease onset and progression. The integration of multi-omics approaches has enhanced our comprehension of the molecular mechanisms underlying IBD, paving the way for personalized medicine. Looking forward, this review emphasizes the need for longitudinal studies and advanced bioinformatics tools to decode the intricate networks involved in IBD. Additionally, we discuss the potential of novel therapeutic strategies, including epigenetic drugs and microbiome modulation, as promising avenues for improved patient outcomes. This comprehensive overview provides a foundation for future research aimed at unraveling the complexities of IBD and developing innovative treatments tailored to the Spanish population. Full article
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7 pages, 199 KiB  
Article
A Very Low-Calorie Ketogenic Diet Approach for Post-Bariatric Weight Regain: A Pilot Study
by Ilaria Ernesti, Mikiko Watanabe and Alfredo Genco
J 2024, 7(4), 482-488; https://doi.org/10.3390/j7040029 - 12 Nov 2024
Viewed by 944
Abstract
Weight regain (WR) after bariatric surgery, particularly sleeve gastrectomy, is a significant challenge, often driven by a combination of metabolic, behavioral, and lifestyle factors. Non-surgical interventions to manage WR are critical, given the increased risks and reduced efficacy of revisional surgeries. In this [...] Read more.
Weight regain (WR) after bariatric surgery, particularly sleeve gastrectomy, is a significant challenge, often driven by a combination of metabolic, behavioral, and lifestyle factors. Non-surgical interventions to manage WR are critical, given the increased risks and reduced efficacy of revisional surgeries. In this context, very low-calorie ketogenic diets (VLCKDs) have gained attention for their potential to promote weight loss and improve body composition in individuals struggling with WR. This study assessed the safety and efficacy of a VLCKD in 11 patients who experienced WR following sleeve gastrectomy. Over an 8-week period, patients demonstrated a significant average weight loss of 6.3% (p = 0.005), along with improvements in body composition, including reductions in body fat percentage (p = 0.003) and waist circumference (p = 0.003). Metabolic markers, such as insulin resistance (HOMA-IR), also improved significantly (p = 0.041). Although a decrease in the glomerular filtration rate was observed (p = 0.007), this finding is unlikely to be clinically relevant over the short term. Importantly, no major adverse events were reported, with only mild constipation observed. These results suggest that VLCKDs may be a promising non-surgical approach for managing WR post-bariatric surgery, though further studies are needed to assess long-term effects, especially on renal function. Full article
10 pages, 893 KiB  
Article
Exposure to Gas Flaring Among Residents of Oil-Producing Communities in Bayelsa State, Niger Delta Region of Nigeria: A Cross-Sectional Study of Haematological Indices
by Domotimi James Jato, Felix M. Onyije, Osaro O. Mgbere and Godwin Ovie Avwioro
J 2024, 7(4), 472-481; https://doi.org/10.3390/j7040028 - 11 Nov 2024
Viewed by 929
Abstract
Air pollution contributes significantly to morbidity and mortality globally. The Niger Delta Region of Nigeria flares the second largest amount of natural gas in the world, with residents of oil-producing communities bearing the burden of outdoor pollution that may have adverse effects on [...] Read more.
Air pollution contributes significantly to morbidity and mortality globally. The Niger Delta Region of Nigeria flares the second largest amount of natural gas in the world, with residents of oil-producing communities bearing the burden of outdoor pollution that may have adverse effects on their health and well-being. Our study aimed to investigate the haematological indices of residents of a selected gas-flaring site. We conducted a cross-sectional study, wherein a total of eighty adults aged 24 to 73 years were recruited from communities located within a radius of approximately 5 to 10 km from the gas-flaring facility. Blood specimens were collected from consenting participants and analysed for various haematological parameters, including Red Blood Cell (RBC) count, Packed Cell Volume (PCV), Haemoglobin (HB), Mean Cell Haemoglobin (MCH), platelet count (PLT), White Blood Cell (WBC) count, neutrophil (NEU), lymphocytes (LYMs), and Monocyte + Basophil + Eosinophil (MXD). The analysis was performed using an automated Sysmex KX21N haematological analyser. Overall, there was a significant decrease in RBC counts (p < 0.001) and a significant elevation in WBCs (p < 0.001) among people residing within a 5 km radius compared to those residing within a 10 km radius. About 42.5% of males residing within a 5 Km radius exhibited low RBC counts in contrast to only 15% of males residing within a 10 km radius. The WBC levels were found to be significantly higher (p < 0.001) than the reference range among both males and females residing within a 5 km radius compared to those residing at a distance of 10 km. In the female population, 15% of individuals residing within a 5 km and 10 Km radius exhibited RBC levels below the reference category, while 7.5% showed RBC levels above the reference range. Exposure to gas flaring may alter haematological indices. It is, therefore, recommended that a comprehensive longitudinal study be conducted among residents of oil-producing communities and workers at gas-flaring facilities in the Niger Delta region of Nigeria to assess the potential environmental and health implications of their exposure to chemical pollutants. Full article
(This article belongs to the Special Issue Feature Papers of J—Multidisciplinary Scientific Journal in 2024)
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15 pages, 1010 KiB  
Review
Emerging Technologies for the Assessment of Natural Killer Cell Activity
by Anna Luise Grab and Alexander Nesterov-Müller
J 2024, 7(4), 457-471; https://doi.org/10.3390/j7040027 - 7 Nov 2024
Viewed by 1226
Abstract
Understanding natural killer (NK) cell functionality is essential in developing more effective immunotherapeutic strategies that can enhance patient outcomes, especially in the context of cancer treatment. This review provides a comprehensive overview of both traditional and novel techniques for evaluating NK cell functionality, [...] Read more.
Understanding natural killer (NK) cell functionality is essential in developing more effective immunotherapeutic strategies that can enhance patient outcomes, especially in the context of cancer treatment. This review provides a comprehensive overview of both traditional and novel techniques for evaluating NK cell functionality, focusing on multiparameter assays and spatial methods that illuminate NK cell interactions within their microenvironment. We discuss the significance of standardized assays for assessing NK cell function across various research and clinical settings, including cancer immunotherapy, infectious diseases, and transplantation. Key factors influencing NK cell functionality include the origin of the sample, target–effector ratios, the functional state of NK cells, and the impact of pre-treatment conditions and their natural aging effect on NK cell activity. By emphasizing the importance of selecting a suitable technique for reliable measurements, especially for longitudinal monitoring, this review aims to give an overview on techniques to measure NK cell functionality in vitro and show the interaction with their microenvironment cells by spatial imaging. Ultimately, our understanding of NK cell functionality could be critical to biomarker development, drug design, and understanding of disease progression in the field of oncology or infectious disease. Full article
(This article belongs to the Section Medicine & Pharmacology)
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18 pages, 3678 KiB  
Review
Electrification or Hydrogen? The Challenge of Decarbonizing Industrial (High-Temperature) Process Heat
by Jörg Leicher, Anne Giese and Christoph Wieland
J 2024, 7(4), 439-456; https://doi.org/10.3390/j7040026 - 28 Oct 2024
Viewed by 1727
Abstract
The decarbonization of industrial process heat is one of the bigger challenges of the global energy transition. Process heating accounts for about 20% of final energy demand in Germany, and the situation is similar in other industrialized nations around the globe. Process heating [...] Read more.
The decarbonization of industrial process heat is one of the bigger challenges of the global energy transition. Process heating accounts for about 20% of final energy demand in Germany, and the situation is similar in other industrialized nations around the globe. Process heating is indispensable in the manufacturing processes of products and materials encountered every day, ranging from food, beverages, paper and textiles, to metals, ceramics, glass and cement. At the same time, process heating is also responsible for significant greenhouse gas emissions, as it is heavily dependent on fossil fuels such as natural gas and coal. Thus, process heating needs to be decarbonized. This review article explores the challenges of decarbonizing industrial process heat and then discusses two of the most promising options, the use of electric heating technologies and the substitution of fossil fuels with low-carbon hydrogen, in more detail. Both energy carriers have their specific benefits and drawbacks that have to be considered in the context of industrial decarbonization, but also in terms of necessary energy infrastructures. The focus is on high-temperature process heat (>400 °C) in energy-intensive basic materials industries, with examples from the metal and glass industries. Given the heterogeneity of industrial process heating, both electricity and hydrogen will likely be the most prominent energy carriers for decarbonized high-temperature process heat, each with their respective advantages and disadvantages. Full article
(This article belongs to the Section Engineering)
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18 pages, 1746 KiB  
Article
Energy Performance Analysis and Output Prediction Pipeline for East-West Solar Microgrids
by Khanh Nguyen, Kevin Koch, Swati Chandna and Binh Vu
J 2024, 7(4), 421-438; https://doi.org/10.3390/j7040025 - 21 Oct 2024
Viewed by 1022
Abstract
Local energy networks, known as microgrids, can operate independently or in conjunction with the main grid, offering numerous benefits such as enhanced reliability, sustainability, and efficiency. This study focuses on analyzing the factors that influence energy performance in East-West microgrids, which have the [...] Read more.
Local energy networks, known as microgrids, can operate independently or in conjunction with the main grid, offering numerous benefits such as enhanced reliability, sustainability, and efficiency. This study focuses on analyzing the factors that influence energy performance in East-West microgrids, which have the unique advantage of capturing solar radiation from both directions, maximizing energy production throughout the day. A predictive pipeline was also developed to assess the performance of various machine learning models in forecasting energy output. Key input data for the models included solar radiation levels, photovoltaic (DC) energy, and the losses incurred during the conversion from DC to AC energy. One of the study’s significant findings was that the east side of the microgrid received higher radiation and experienced fewer losses compared to the west side, illustrating the importance of orientation for efficiency. Another noteworthy result was the predicted total energy supplied to the grid, valued at €15,423. This demonstrates that the optimized energy generation not only meets grid demand but also generates economic value by enabling the sale of excess energy back to the grid. The machine learning models—Random Forest, Extreme Gradient Boosting, and Recurrent Neural Networks—showed superior performance in energy prediction, with mean squared errors of 0.000318, 0.000104, and 0.000081, respectively. The research concludes that East-West microgrids have substantial potential to generate significant energy and economic benefits. The developed energy prediction pipeline can serve as a useful tool for optimizing microgrid operations and improving their integration with the main grid. Full article
(This article belongs to the Section Computer Science & Mathematics)
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15 pages, 388 KiB  
Article
An Enhanced Learning with Error-Based Cryptosystem: A Lightweight Quantum-Secure Cryptography Method
by Mostefa Kara, Konstantinos Karampidis, Giorgos Papadourakis, Mohammad Hammoudeh and Muath AlShaikh
J 2024, 7(4), 406-420; https://doi.org/10.3390/j7040024 - 13 Oct 2024
Viewed by 1424
Abstract
Quantum-secure cryptography is a dynamic field due to its crucial role in various domains. This field aligns with the ongoing efforts in data security. Post-quantum encryption (PQE) aims to counter the threats posed by future quantum computers, highlighting the need for further improvement. [...] Read more.
Quantum-secure cryptography is a dynamic field due to its crucial role in various domains. This field aligns with the ongoing efforts in data security. Post-quantum encryption (PQE) aims to counter the threats posed by future quantum computers, highlighting the need for further improvement. Based on the learning with error (LWE) system, this paper introduces a novel asymmetric encryption technique that encrypts entire messages of n bits rather than just 1 bit. This technique offers several advantages including an additive homomorphic cryptosystem. The robustness of the proposed lightweight public key encryption method, which is based on a new version of LWE, ensures that private keys remain secure and that original data cannot be recovered by an attacker from the ciphertext. By improving encryption and decryption execution time—which achieve speeds of 0.0427 ms and 0.0320 ms, respectively—and decreasing ciphertext size to 708 bits for 128-bit security, the obtained results are very promising. Full article
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