The 2023 MDPI Annual Report has
been released!
 
19 pages, 26111 KiB  
Article
Optimization Design of Variable Reluctance Resolver Based on Three-phase Symmetrical Winding
by Xinmin Li, Jiannan Chen and Zhen Zhang
World Electr. Veh. J. 2024, 15(5), 201; https://doi.org/10.3390/wevj15050201 - 06 May 2024
Abstract
In order to ease the structure and manufacturing process of the variable reluctance (VR) resolver, the three-phase symmetrical single-layer winding commonly used in the stator winding of permanent magnet synchronous motors (PMSM) is applied to the VR resolver in this paper. The proposed [...] Read more.
In order to ease the structure and manufacturing process of the variable reluctance (VR) resolver, the three-phase symmetrical single-layer winding commonly used in the stator winding of permanent magnet synchronous motors (PMSM) is applied to the VR resolver in this paper. The proposed resolver has the same winding direction and number of turns on all teeth. And the non-overlapping distribution of the three-phase windings of the resolver is ensured. For this novel resolver, the resolver-to-digital conversion (RDC) method references the ultra-high-frequency (UHF) signal injection method used when a PMSM is powered off and restarted. Instead of the need for the orthogonal envelope RDC required by conventional resolvers, the absolute position of the rotor can be obtained. In this paper, the prototype of the proposed resolver and the peripheral circuits are fabricated and compared with the position detected by the optical encoder, and the validity of the proposed resolver and the accuracy of the RDC are verified by the results of the comparison experiments. Full article
Show Figures

Figure 1

14 pages, 2580 KiB  
Article
Improved Equivalent Strain Method for Fatigue Life of Automobile Aluminum Alloy
by Shanjie Zhi, Hejian Liu and Xintian Liu
World Electr. Veh. J. 2024, 15(5), 200; https://doi.org/10.3390/wevj15050200 - 06 May 2024
Abstract
Automotive parts are usually subjected to random loads with large mean tensile/compressive stresses under working conditions. It is important for automotive parts to have a long fatigue life under mean stress in practical engineering applications. An equivalent strain model is established here to [...] Read more.
Automotive parts are usually subjected to random loads with large mean tensile/compressive stresses under working conditions. It is important for automotive parts to have a long fatigue life under mean stress in practical engineering applications. An equivalent strain model is established here to predict fatigue life considering the influence of mean strain and stress under asymmetric cycles. To predict the fatigue life more accurately, the coefficient of surface roughness and temperature correction is introduced in this model. The effectiveness of the improved equivalent strain (IES) model is verified by comparing it with multiple sets of experimental data. The IES is also compared with Smith–Watson–Topper (SWT), Manson–Coffin, and equivalent strain models. The results show that the developed model has a higher prediction accuracy than the other models. An improved fatigue strength exponent is introduced to modify the equivalent strain model, and the effectiveness of the model is verified by experimental data. The IES model demonstrates significantly reduced standard deviations under various strain ratios (−0.06, 0.06, 0.5), with measurements of 0.0936, 0.0721, and 0.0636, respectively. The method provides a certain reference for the life prediction of automotive parts. Full article
(This article belongs to the Special Issue Electric Vehicle Networking and Traffic Control)
Show Figures

Figure 1

14 pages, 3566 KiB  
Article
Effect of Climate Evolution on the Dynamics of the Wildfires in Greece
by Nikolaos Iliopoulos, Iasonas Aliferis and Michail Chalaris
Fire 2024, 7(5), 162; https://doi.org/10.3390/fire7050162 - 06 May 2024
Abstract
Understanding the potential effects of climate change on forest fire behavior and the resulting release of combustion products is critical for effective mitigation strategies in Greece. This study utilizes data from the MAGICC 2.4 (Model for the Assessment of Greenhouse Gas-Induced Climate Change) [...] Read more.
Understanding the potential effects of climate change on forest fire behavior and the resulting release of combustion products is critical for effective mitigation strategies in Greece. This study utilizes data from the MAGICC 2.4 (Model for the Assessment of Greenhouse Gas-Induced Climate Change) climate model and the SCENGEN 2.4 (SCENarioGENerator) database to assess these impacts. By manipulating various model parameters such as climate sensitivity, scenario, time period, and global climate models (GCMs) within the SCENGEN 2.4 database, we analyzed climatic trends affecting forest fire generation and evolution. The results reveal complex and nuanced findings, indicating a need for further investigation. Case studies are conducted using the FARSITE 4 (Fire Area Simulator) model, incorporating meteorological changes derived from climate trends. Simulations of two fires in East Attica, accounting for different fuel and meteorological conditions, demonstrate an increase in the rate of combustion product release. This underscores the influence of changing meteorological parameters on forest fire dynamics and highlights the importance of proactive measures to mitigate future risks. Our findings emphasize the urgency of addressing climate change impacts on wildfire behavior to safeguard environmental and public health in Greece. Full article
(This article belongs to the Special Issue Effects of Climate Change on Fire Danger)
Show Figures

Figure 1

12 pages, 989 KiB  
Review
A Focused Review on Wildfire Evacuation and Infrastructure Resilience in Canada: Trends and Insights (2013–2023)
by Nima Karimi
Fire 2024, 7(5), 161; https://doi.org/10.3390/fire7050161 - 06 May 2024
Abstract
This review paper investigates the landscape of wildfire-related studies with a focus on infrastructure and evacuations across Canadian provinces, revealing a predominant focus on Alberta, particularly after the 2016 Fort McMurray wildfire. The aftermath of this event has heightened attention to the unique [...] Read more.
This review paper investigates the landscape of wildfire-related studies with a focus on infrastructure and evacuations across Canadian provinces, revealing a predominant focus on Alberta, particularly after the 2016 Fort McMurray wildfire. The aftermath of this event has heightened attention to the unique challenges faced during evacuations, emphasizing the urgent need for heightened awareness and preparedness, especially in the vulnerable northern communities of Alberta. Studies beyond Alberta contribute to understanding Canadian wildfire dynamics. However, a noticeable research gap in British Columbia raises concerns about research prioritization and resource allocation despite heightened wildfire activity. The fact that some provinces are contributing less than 4.2%, such as Quebec, Saskatchewan, Ontario, Northwest Territories, Yukon, and the Prairies, might be attributed to regional variations influenced by historical wildfire frequency and population density. Thematic analysis categorizing studies into “community support/resilience”, “evacuation efficiency”, and “infrastructure protection/raising awareness” provides nuanced insights. The dominance of the “community support/resilience” category, comprising over 40% of studies, signifies a societal shift towards proactive community engagement. Balanced representation in the “evacuation efficiency” and “infrastructure protection/raising awareness” categories, each contributing over 29%, reflects a collective effort to glean lessons from past evacuations and enhance community preparedness. Temporal trends and thematic analyses spotlight a commitment to continuous improvement, adaptability to emerging challenges, and a growing recognition of the multifaceted aspects of wildfire management. The evolving emphasis on community involvement, responsiveness to changing evacuation dynamics, and heightened awareness of infrastructure protection underscores the proactive stance of the research community, providing insights for shaping future research priorities, policy frameworks, and community resilience strategies in the face of evolving wildfire threats in Canada. Full article
Show Figures

Figure 1

14 pages, 2486 KiB  
Article
Thermomechanical Responses and Energy Conversion Efficiency of a Hybrid Thermoelectric–Piezoelectric Layered Structure
by Zhihe Jin and Jiashi Yang
J. Compos. Sci. 2024, 8(5), 171; https://doi.org/10.3390/jcs8050171 - 06 May 2024
Abstract
This paper develops a thermoelectric (TE)–piezoelectric (PE) hybrid structure with the PE layer acting as both a support membrane and a sensor for the TE film for microelectronics applications. The TE and PE layers are assumed to be perfectly bonded mechanically and thermally [...] Read more.
This paper develops a thermoelectric (TE)–piezoelectric (PE) hybrid structure with the PE layer acting as both a support membrane and a sensor for the TE film for microelectronics applications. The TE and PE layers are assumed to be perfectly bonded mechanically and thermally but electrically shielded and insulated with each other. The thermo-electro-mechanical responses of the hybrid bilayer under the TE generator operation conditions are obtained, and the influence of the PE layer on the TE energy conversion efficiency is investigated. The numerical results for a Bi2Te3/PZT-5H bilayer structure show that large compressive stresses develop in both the PE and TE layers. With a decrease in the PE layer thickness, the magnitude of the maximum compressive stress in the PE layer increases whereas the maximum magnitude of the stress in the TE layer decreases. The numerical result of the TE energy conversion efficiency shows that increasing the PE layer thickness leads to lower energy conversion efficiencies. A nearly 40% reduction in the peak efficiency is observed with a PE layer of the same thickness as that of the TE layer. These results suggest that design of TE films with supporting/sensing membranes must consider both aspects of energy conversion efficiency and the thermomechanical reliability of both the TE and PE layers. Full article
(This article belongs to the Special Issue Theoretical and Computational Investigation on Composite Materials)
Show Figures

Figure 1

13 pages, 4366 KiB  
Article
Infectious Diseases and Secondary Antibody Deficiency in Patients from a Mesoregion of São Paulo State, Brazil
by Luiz Euribel Prestes-Carneiro, Paula Andreia Martins Carrilho, Danielle Francisco Honorato de Barros Torelli, Jose Antonio Nascimento Bressa, Ana Carolina Gomes Parizi, Pedro Henrique Meireles Vieira, Fernanda Miranda Caliani Sa and Mauricio Domingues Ferreira
Trop. Med. Infect. Dis. 2024, 9(5), 104; https://doi.org/10.3390/tropicalmed9050104 - 06 May 2024
Abstract
Our aim was to determine the secondary antibody deficiency (SAD) profiles of patients in a mesoregion of São Paulo state, Brazil, focusing on infectious diseases. Demographic characteristics, and clinical and laboratory data were obtained from electronic files; infections were classified as organ-specific and [...] Read more.
Our aim was to determine the secondary antibody deficiency (SAD) profiles of patients in a mesoregion of São Paulo state, Brazil, focusing on infectious diseases. Demographic characteristics, and clinical and laboratory data were obtained from electronic files; infections were classified as organ-specific and graded as mild, moderate, life-threatening, and fatal. Non-Hodgkin’s lymphoma (NHL) accounted for 30% of patients, nephrotic syndrome (NS) 25%, chronic lymphocyte leukemia 20%, and multiple myeloma 15%. Patients with NS were younger than those in other groups, and hypo-γ-globulinemia was detected in 94.1%, IgG < 400 mg/dL in 60.0%, IgA < 40 mg/dL in 55.0%, and CD19 < 20 cells/mm3 in 30.0%. One hundred and one infections were found; 82.1% were classified as mild or moderate, 7.9% as life-threatening, and 3.0% as fatal. Respiratory tract infections were more prevalent (41.5%), and pneumonia accounted for 19.8%. Lower levels of infections were found in patients with NS compared with NHL (p = 0.0001). Most patients progressed to hypo-γ-globulinemia and SAD after treatment with immunosuppressants, and mild and moderate infections were predominant. These therapies are increasing in patients with different diseases; therefore, monitoring hypo-γ-globulinemia and infections may help to identify patients at high risk for severe complications, antibiotic prophylaxis or treatment, and immunoglobulin replacement. Full article
Show Figures

Figure 1

17 pages, 379 KiB  
Article
Can Crisis Periods Affect the ESG Reporting Scope? The Portuguese Euronext Entities Case
by Catarina Cepeda
J. Risk Financial Manag. 2024, 17(5), 191; https://doi.org/10.3390/jrfm17050191 - 06 May 2024
Abstract
Portuguese companies are increasingly responding to the demand of stakeholders for transparent information about companies’ environmental, social, and governance (ESG) performance by issuing non-financial reports (NFRs). While the number of NFRs published annually has been increasing over the last two decades, their quality [...] Read more.
Portuguese companies are increasingly responding to the demand of stakeholders for transparent information about companies’ environmental, social, and governance (ESG) performance by issuing non-financial reports (NFRs). While the number of NFRs published annually has been increasing over the last two decades, their quality and companies’ ESG performance have been questioned, especially in times of crisis. To address these concerns, several jurisdictions have introduced mandatory NFR rules, such as the European Directive 2014/95/EU. Employing an institutional theory lens, this paper’s research objective is to evaluate whether the last decade’s crises and whether the fact that NFRs became mandatory for certain entities positively affected companies’ activities covered in the ESG reporting scope. We used panel data regression models on 45 listed companies in Portugal during the period 2008–2021. Our results show that the ESG reporting scope is not positively influenced by the transition from NFRs to a mandatory and global financial crisis (GFC). However, the COVID-19 crisis positively affected NFR quality. These results have major implications for practitioners, reflecting the importance of promoting these tools in an organization to improve non-financial performance and companies’ sustainability. Full article
(This article belongs to the Special Issue Financial Reporting and Auditing)
22 pages, 3260 KiB  
Article
The Effects of Tremella fuciformis Polysaccharide on the Physicochemical, Multiscale Structure and Digestive Properties of Cyperus esculentus Starch
by Shanshan Zhang, Yingxu Liu, Tong Sun, Hongcheng Liu and Dawei Wang
Foods 2024, 13(9), 1425; https://doi.org/10.3390/foods13091425 - 06 May 2024
Abstract
In this study, we have investigated the effects of Tremella fuciformis polysaccharide (TP) on the pasting, rheological, structural and in vitro digestive properties of Cyperus esculentus starch (CS). The results showed that the addition of TP significantly changed the pasting characteristics of CS, [...] Read more.
In this study, we have investigated the effects of Tremella fuciformis polysaccharide (TP) on the pasting, rheological, structural and in vitro digestive properties of Cyperus esculentus starch (CS). The results showed that the addition of TP significantly changed the pasting characteristics of CS, increased the pasting temperature and pasting viscosity, inhibited pasting, reduced the exudation of straight-chain starch and was positively correlated with the amount of TP added. The addition of the appropriate amount of TP could increase its apparent viscosity and enhance its viscoelasticity. The composite system of CS/TP exhibited higher short-range ordered structure and solid dense structure, which protected the crystal structure of CS, but was related to the amount of TP added. In addition, the introduction of TP not only decreased the in vitro digestion rate of CS and increased the content of slow-digestible starch (SDS) and resistant starch (RS), but also reduced the degree of digestion. Correlation studies established that TP could improve the viscoelasticity, relative crystallinity and short-range order of the CS/TP composite gel, maintain the integrity of the starch granule and crystalline structure, reduce the degree of starch pasting and strengthen the gel network structure of CS, which could help to lower the digestibility of CS. Full article
(This article belongs to the Special Issue Starch and Food Processing: Structure, Functionality and Nutrition)
21 pages, 1086 KiB  
Article
Analysis of Actual Fitness Supplement Consumption among Health and Fitness Enthusiasts
by Paolo Renzo Espeño, Ardvin Kester S. Ong, Josephine D. German, Ma. Janice J. Gumasing and Ethan S. Casas
Foods 2024, 13(9), 1424; https://doi.org/10.3390/foods13091424 - 06 May 2024
Abstract
With the rising popularity of fitness supplements, understanding the factors driving their consumption behaviors is crucial. This study investigated the actual consumption of fitness supplements utilizing the Theory of Planned Behavior (TPB), Health Belief Model (HBM), and the Theory of Effort Minimization in [...] Read more.
With the rising popularity of fitness supplements, understanding the factors driving their consumption behaviors is crucial. This study investigated the actual consumption of fitness supplements utilizing the Theory of Planned Behavior (TPB), Health Belief Model (HBM), and the Theory of Effort Minimization in Physical Activity (TEMPA) frameworks. The TPB provided insights into how attitudes, subjective norms, and perceived behavioral control influence individuals’ intentions to consume fitness supplements. Additionally, the HBM sheds light on perceived effectiveness, benefits, barriers, and health motivation related to supplement consumption. Integrating the TEMPA framework further investigated the role of effort minimization in physical activity contexts. Through an online questionnaire, data were collected from a sample of 250 fitness supplement-consuming respondents. SEM analysis revealed significant associations between behavioral intentions and attitudes, perceived behavioral control, health motivation, and controlled precursors. However, it was seen that subjective norms, perceived effectiveness, perceived benefits, and automatic precursors were deemed insignificant. The findings contribute to a comprehensive understanding of the factors shaping actual consumption behaviors, offering valuable implications for marketers, health professionals, and policymakers seeking to promote informed and responsible supplement use among health and fitness enthusiasts. Full article
17 pages, 684 KiB  
Article
A Sustainable Material for Sheep’s Cheese Wedges Stored under Different Atmosphere Conditions
by Ana Isabel Nájera, Maider Murua, Olaia Martínez, Marta Albisu and Luis Javier R. Barron
Foods 2024, 13(9), 1423; https://doi.org/10.3390/foods13091423 - 06 May 2024
Abstract
This study is based on the need to improve packaging sustainability in the food industry. Its aim was to assess the performance of a recyclable plastic material for semi-hard sheep’s cheese wedges packaging as an alternative to conventional non-sustainable plastic materials. Four different [...] Read more.
This study is based on the need to improve packaging sustainability in the food industry. Its aim was to assess the performance of a recyclable plastic material for semi-hard sheep’s cheese wedges packaging as an alternative to conventional non-sustainable plastic materials. Four different packaging treatments (air, vacuum, and CO2/N2 gas mixtures 50/50 and 80/20% (v/v)) were studied. Changes in gas headspace composition, sensory properties, cheese gross composition, weight loss, pH, colour, and texture profile were investigated at 5 ± 1 °C storage for 56 days. The sensory analysis indicated that vacuum packaging scored the worst in paste appearance and holes, and air atmosphere the worst in flavour; it was concluded that cheeses were unfit from day 14–21 onwards. Air and vacuum packaging were responsible for most of the significant changes identified in the texture profile analysis, and most of these happened in the early stages of storage. The colour parameters a* and b* differentiated the air packaging from the rest of the conditions. As in previous studies using conventional plastic materials, modified atmosphere packaging, either CO2/N2 50/50 or 80/20% (v/v), was the most effective preserving technique to ensure the quality of this type of cheese when comparing air and vacuum packaging treatments. Full article
(This article belongs to the Special Issue Recent Advances in Cheese and Fermented Milk Production)
17 pages, 1518 KiB  
Article
Effects of Soaking and Germination Treatments on the Nutritional, Anti-Nutritional, and Bioactive Characteristics of Adzuki Beans (Vigna angularis L.) and Lima Beans (Phaseolus lunatus L.)
by Qurat Ul Eain Hyder Rizvi, Raquel P. F. Guiné, Naseer Ahmed, Mohd Aaqib Sheikh, Paras Sharma, Imran Sheikh, Ajar Nath Yadav and Krishan Kumar
Foods 2024, 13(9), 1422; https://doi.org/10.3390/foods13091422 - 06 May 2024
Abstract
Lima beans (Phaseolus lunatus) and adzuki beans (Vigna angularis) are some of the most nutritious underutilized pulses that are significant in being used as basic ingredients for the preparation of various food products. The present study aimed to determine [...] Read more.
Lima beans (Phaseolus lunatus) and adzuki beans (Vigna angularis) are some of the most nutritious underutilized pulses that are significant in being used as basic ingredients for the preparation of various food products. The present study aimed to determine the impact of soaking and germination on nutritional and bioactive components, in vitro protein digestibility, reducing power, metal chelating capacity, antioxidant activity, and anti-nutritional components of lima and adzuki beans. The findings showed that during the germination treatment, the in vitro protein digestibility of lima and adzuki beans increased by 14.75 and 10.98%, respectively. There was an increase in the antioxidant activity of lima beans by 33.48% and adzuki beans by 71.14% after 72 h of germination, respectively. The reducing power assay of lima and adzuki beans indicated an increase of 49.52 and 36.42%, respectively, during germination. Similarly, the flavonoid and metal chelating activity increased in lima and adzuki beans after 72 h of germination. In contrast, the anti-nutrients, such as phytic acid, tannin content, and trypsin inhibitor activity, decreased significantly p < 0.05 after 72 h of germination. These results are encouraging and allow for utilizing the flour obtained from the germinated beans in functional bakery products, which can contribute to eradicating protein deficiency among some population groups. At the same time, promoting soaking and germination of the beans as a way to enhance the nutritional quality and reduce anti-nutrients can contribute to the interest in these underutilized pulses. They could be seen as an additional tool to improve food security. Full article
(This article belongs to the Special Issue The Challenges and Strategies of Food Security under Global Change)
Show Figures

Figure 1

17 pages, 4051 KiB  
Article
Microalgae Biomass Production from Rice Husk as Alternative Media Cultivation and Extraction of Phycocyanin Using 3D-Printed Ohmic Heating Reactor
by Gabriela Cid-Ibarra, Rosa M. Rodríguez-Jasso, Gilver Rosero-Chasoy, Ruth Belmares, Juan Carlos Contreras-Esquivel, Samanta Machado-Cepeda, Alejandra Cabello-Galindo and Héctor A. Ruiz
Foods 2024, 13(9), 1421; https://doi.org/10.3390/foods13091421 - 06 May 2024
Abstract
Phycocyanin is a highly valued pigment present in Spirulina platensis biomass with applications in the food industry in terms of biorefinery concepts; specifically, its antioxidant and antimicrobial capacity are an advantage that could be incorporated into a food matrix. This study aims to [...] Read more.
Phycocyanin is a highly valued pigment present in Spirulina platensis biomass with applications in the food industry in terms of biorefinery concepts; specifically, its antioxidant and antimicrobial capacity are an advantage that could be incorporated into a food matrix. This study aims to use rice husk as an alternative culture medium for S. platensis biomass growth and phycocyanin extraction by ohmic heating processing using a 3D-printed reactor. S. platensis was cultivated in rice husk extract (RHE) from 0–100% (v/v). The highest content of microalgal biomass was 1.75 ± 0.01 g/L, with a specific growth rate of 0.125 ± 0.01 h−1. For the phycocyanin extraction under an ohmic heating process, a 3D-printed reactor was designed and built. To optimize phycocyanin extraction, a central composite rotatable design (CCDR) was evaluated, with three factors: time (min), temperature (°C), and pH. The highest phycocyanin content was 75.80 ± 0.98 mg/g in S. platensis biomass grown with rice husk extract. Ohmic heating is a promising method for rapid phycocyanin extraction, and rice husk as a culture medium is an alternative for the growth of S. platensis biomass in the integration of second- and third-generation biorefineries. Full article
Show Figures

Figure 1

15 pages, 6472 KiB  
Article
Characterizing Edible Oils by Oblique-Incidence Reflectivity Difference Combined with Machine Learning Algorithms
by Xiaorong Sun, Yiran Hu, Cuiling Liu, Shanzhe Zhang, Sining Yan, Xuecong Liu and Kun Zhao
Foods 2024, 13(9), 1420; https://doi.org/10.3390/foods13091420 - 06 May 2024
Abstract
Due to the significant price differences among different types of edible oils, expensive oils like olive oil are often blended with cheaper edible oils. This practice of adulteration in edible oils, aimed at increasing profits for producers, poses a major concern for consumers. [...] Read more.
Due to the significant price differences among different types of edible oils, expensive oils like olive oil are often blended with cheaper edible oils. This practice of adulteration in edible oils, aimed at increasing profits for producers, poses a major concern for consumers. Furthermore, adulteration in edible oils can lead to various health issues impacting consumer well-being. In order to meet the requirements of fast, non-destructive, universal, accurate, and reliable quality testing for edible oil, the oblique-incidence reflectivity difference (OIRD) method combined with machine learning algorithms was introduced to detect a variety of edible oils. The prediction accuracy of Gradient Boosting, K-Nearest Neighbor, and Random Forest models all exceeded 95%. Moreover, the contribution rates of the OIRD signal, DC signal, and fundamental frequency signal to the classification results were 45.7%, 34.1%, and 20.2%, respectively. In a quality evaluation experiment on olive oil, the feature importance scores of three signals reached 63.4%, 18.9%, and 17.6%. The results suggested that the feature importance score of the OIRD signal was significantly higher than that of the DC and fundamental frequency signals. The experimental results indicate that the OIRD method can serve as a powerful tool for detecting edible oils. Full article
(This article belongs to the Section Food Physics and (Bio)Chemistry)
Show Figures

Figure 1

5 pages, 207 KiB  
Editorial
Plant Bioactive Compounds in Foods and Food Packages
by Ginés Benito Martínez-Hernández, Amaury Taboada-Rodríguez and Fulgencio Marin-Iniesta
Foods 2024, 13(9), 1419; https://doi.org/10.3390/foods13091419 - 06 May 2024
Abstract
There has been growing interest in the use of numerous plant bioactive compounds (PBCs) in food and nutrition technology due to their properties that promote human health by reducing the risk of various serious diseases [...] Full article
(This article belongs to the Special Issue Plant Bioactive Compounds in Foods and Food Packages)
57 pages, 5811 KiB  
Review
Naturally Occurring Norsteroids and Their Design and Pharmaceutical Application
by Valery M. Dembitsky
Biomedicines 2024, 12(5), 1021; https://doi.org/10.3390/biomedicines12051021 - 06 May 2024
Abstract
The main focus of this review is to introduce readers to the fascinating class of lipid molecules known as norsteroids, exploring their distribution across various biotopes and their biological activities. The review provides an in-depth analysis of various modified steroids, including A, B, [...] Read more.
The main focus of this review is to introduce readers to the fascinating class of lipid molecules known as norsteroids, exploring their distribution across various biotopes and their biological activities. The review provides an in-depth analysis of various modified steroids, including A, B, C, and D-norsteroids, each characterized by distinct structural alterations. These modifications, which range from the removal of specific methyl groups to changes in the steroid core, result in unique molecular architectures that significantly impact their biological activity and therapeutic potential. The discussion on A, B, C, and D-norsteroids sheds light on their unique configurations and how these structural modifications influence their pharmacological properties. The review also presents examples from natural sources that produce a diverse array of steroids with distinct structures, including the aforementioned A, B, C, and D-nor variants. These compounds are sourced from marine organisms like sponges, soft corals, and starfish, as well as terrestrial entities such as plants, fungi, and bacteria. The exploration of these steroids encompasses their biosynthesis, ecological significance, and potential medical applications, highlighting a crucial area of interest in pharmacology and natural product chemistry. The review emphasizes the importance of researching these steroids for drug development, particularly in addressing diseases where conventional medications are inadequate or for conditions lacking sufficient therapeutic options. Examples of norsteroid synthesis are provided to illustrate the practical applications of this research. Full article
(This article belongs to the Special Issue Steroids and Their Derivatives as Potential Drugs for Medicine)
Show Figures

Graphical abstract

19 pages, 796 KiB  
Article
The Impact of Disease Duration on Microcirculatory Dysfunction in Young Patients with Uncomplicated Type 1 Diabetes
by Jolanta Neubauer-Geryk, Melanie Wielicka, Magdalena Hoffmann, Małgorzata Myśliwiec and Leszek Bieniaszewski
Biomedicines 2024, 12(5), 1020; https://doi.org/10.3390/biomedicines12051020 - 06 May 2024
Abstract
This study aimed to evaluate the earliest changes in the structure and function of the peripheral microcirculation using capillaroscopy and transcutaneous oxygen pressure measurement in children and adolescents with type 1 diabetes mellitus at baseline and during post-occlusive reactive hyperemia (PORH) in the [...] Read more.
This study aimed to evaluate the earliest changes in the structure and function of the peripheral microcirculation using capillaroscopy and transcutaneous oxygen pressure measurement in children and adolescents with type 1 diabetes mellitus at baseline and during post-occlusive reactive hyperemia (PORH) in the function of diabetes duration. Sixty-seven patients with type 1 diabetes mellitus (T1D), aged 8 to 18 years, and twenty-eight age- and sex-matched healthy subjects were included in the analysis. Diabetic patients were divided into subgroups based on median disease duration. The subgroups differed in chronological age, lipid levels, and thyroid hormones. Capillaroscopy was performed twice: at baseline and then again after the PORH test. Transcutaneous oxygen pressure also was recorded under baseline conditions during and after the PORH test. Comparison of capillaroscopy and transcutaneous oxygen pressure parameters at rest and after the PORH showed no statistically significant difference between the subgroups. This remained true after adjusting for variables that differentiated the two subgroups. However, in the group of patients with long-standing diabetes, significant negative correlations were observed between the Coverage value after the PORH test and capillary reactivity with TcPO2_zero (biological zero). Significant positive correlations were also found between distance after the PORH test and TcPO2_zero. The results of our study indicate that in patients with a shorter duration of diabetes, the use of multiple tests provides a better characterization of the structure and function of microcirculation because the onset of dysfunction does not occur at the same time in all the tests. Full article
(This article belongs to the Special Issue Microcirculation in Health and Diseases)
12 pages, 625 KiB  
Article
Ethnic Variations in the Levels of Bone Biomarkers (Osteoprostegerin, Receptor Activator of Nuclear Factor Kappa-Β Ligand and Glycoprotein Non-Metastatic Melanoma Protein B) in People with Type 2 Diabetes
by Preethi Cherian, Irina Al-Khairi, Mohamed Abu-Farha, Tahani Alramah, Ahmed N. Albatineh, Doha Alhomaidah, Fayez Safadi, Hamad Ali, Muhammad Abdul-Ghani, Jaakko Tuomilehto, Heikki A. Koistinen, Fahd Al-Mulla and Jehad Abubaker
Biomedicines 2024, 12(5), 1019; https://doi.org/10.3390/biomedicines12051019 - 06 May 2024
Abstract
The global incidence of Type 2 diabetes (T2D) is on the rise, fueled by factors such as obesity, sedentary lifestyles, socio-economic factors, and ethnic backgrounds. T2D is a multifaceted condition often associated with various health complications, including adverse effects on bone health. This [...] Read more.
The global incidence of Type 2 diabetes (T2D) is on the rise, fueled by factors such as obesity, sedentary lifestyles, socio-economic factors, and ethnic backgrounds. T2D is a multifaceted condition often associated with various health complications, including adverse effects on bone health. This study aims to assess key biomarkers linked to bone health and remodeling—Osteoprotegerin (OPG), Receptor Activator of Nuclear Factor Kappa-Β Ligand (RANKL), and Glycoprotein Non-Metastatic Melanoma Protein B (GPNMB)—among individuals with diabetes while exploring the impact of ethnicity on these biomarkers. A cross-sectional analysis was conducted on a cohort of 2083 individuals from diverse ethnic backgrounds residing in Kuwait. The results indicate significantly elevated levels of these markers in individuals with T2D compared to non-diabetic counterparts, with OPG at 826.47 (405.8) pg/mL, RANKL at 9.25 (17.3) pg/mL, and GPNMB at 21.44 (7) ng/mL versus 653.75 (231.7) pg/mL, 0.21 (9.94) pg/mL, and 18.65 (5) ng/mL in non-diabetic individuals, respectively. Notably, this elevation was consistent across Arab and Asian populations, except for lower levels of RANKL observed in Arabs with T2D. Furthermore, a positive and significant correlation between OPG and GPNMB was observed regardless of ethnicity or diabetes status, with the strongest correlation (r = 0.473, p < 0.001) found among Arab individuals with T2D. Similarly, a positive and significant correlation between GPNMB and RANKL was noted among Asian individuals with T2D (r = 0.401, p = 0.001). Interestingly, a significant inverse correlation was detected between OPG and RANKL in non-diabetic Arab individuals. These findings highlight dysregulation in bone remodeling markers among individuals with T2D and emphasize the importance of considering ethnic variations in T2D-related complications. The performance of further studies is warranted to understand the underlying mechanisms and develop interventions based on ethnicity for personalized treatment approaches. Full article
Show Figures

Figure 1

16 pages, 2297 KiB  
Article
Dynamics of the State of Arterial Stiffness as a Possible Pathophysiological Factor of Unfavorable Long-Term Prognosis in Patients after Coronary Artery Bypass Grafting
by Alexey N. Sumin, Anna V. Shcheglova and Olga L. Barbarash
Biomedicines 2024, 12(5), 1018; https://doi.org/10.3390/biomedicines12051018 - 06 May 2024
Abstract
The aim of this study was to examine the long-term prognostic value of changes in the cardio-ankle vascular index (CAVI) within a year after coronary artery bypass grafting (CABG). Methods. Patients with coronary artery disease (n = 251) in whom CAVI was [...] Read more.
The aim of this study was to examine the long-term prognostic value of changes in the cardio-ankle vascular index (CAVI) within a year after coronary artery bypass grafting (CABG). Methods. Patients with coronary artery disease (n = 251) in whom CAVI was assessed using the VaSera VS-1000 device before and one year after CABG. Groups with improved CAVI or worsened CAVI were identified. We assessed the following events at follow-up: all-causes death, myocardial infarction, and stroke/transient ischemic attack. Results. All-causes death was significantly more common in the group with worsened CAVI (27.6%) than in the group with CAVI improvement (14.8%; p = 0.029). Patients with worsened CAVI were more likely to have MACE, accounting for 42.2% cases, compared with patients with CAVI improvement, who accounted for 24.5%; p = 0.008. Worsened CAVI (p = 0.024), number of shunts (p = 0.006), and the presence of carotid stenosis (p = 0.051) were independent predictors of death from all causes at 10-year follow-up after CABG. The presence of carotid stenosis (p = 0.002) and the group with worsened CAVI after a year (p = 0.008) were independent predictors of the development of the combined endpoint during long-term follow-up. Conclusions. Patients with worsening CAVI one year after CABG have a poorer prognosis at long-term follow-up than patients with improved CAVI. Future research would be useful to identify the most effective interventions to improve CAVI and correspondingly improve prognosis. Full article
(This article belongs to the Special Issue Pathogenetic Aspects of Cardiovascular and Gastrointestinal Diseases)
Show Figures

Figure 1

14 pages, 249 KiB  
Article
Evaluating Mechanism and Related Axiomatic Results under Multiple Considerations
by Yu-Hsien Liao
Mathematics 2024, 12(9), 1415; https://doi.org/10.3390/math12091415 - 06 May 2024
Abstract
Under many interactive environments in the real world, there is often a need to evaluate the minimization effects and subsequent allocation outcomes derived from these interactions under multiple considerations. For instance, in the context of product sales, it is necessary to evaluate how [...] Read more.
Under many interactive environments in the real world, there is often a need to evaluate the minimization effects and subsequent allocation outcomes derived from these interactions under multiple considerations. For instance, in the context of product sales, it is necessary to evaluate how to minimize the manufacturing costs of various producing factors, and sometimes, from a holistic perspective, it may even be necessary to evaluate situations with minimal sales benefits. On the other hand, in order to evaluate related effects derived from interactions and subsequent allocation outcomes, many game-theoretical studies are based on interactive models to formulate evaluating mechanisms, and then they apply axiomatic processes to analyze the rationality of these mechanisms. Therefore, this study first proposes a mechanism for evaluating the minimization effects and subsequent allocation outcomes under multiple considerations. Additionally, considering that different environmental impacts result from varying participation factors, this study also presents several weighted derivatives based on participation factors and their behaviors. Concurrently, we utilize axiomatic results to demonstrate the mathematical correctness and practicality for these evaluating mechanisms. Full article
22 pages, 1942 KiB  
Article
A Statistical Evaluation Method Based on Fuzzy Failure Data for Multi-State Equipment Reliability
by Jingjing Xu, Qiaobin Yan, Yanhu Pei, Zhifeng Liu, Qiang Cheng, Hongyan Chu and Tao Zhang
Mathematics 2024, 12(9), 1414; https://doi.org/10.3390/math12091414 - 06 May 2024
Abstract
For complex equipment, it is easy to over-evaluate the impact of failure on production by estimating the reliability level only through failure probability. To remedy this problem, this paper proposes a statistical evaluation method based on fuzzy failure data considering the multi-state characteristics [...] Read more.
For complex equipment, it is easy to over-evaluate the impact of failure on production by estimating the reliability level only through failure probability. To remedy this problem, this paper proposes a statistical evaluation method based on fuzzy failure data considering the multi-state characteristics of equipment failures. In this method, the new reliability-evaluation scheme is firstly presented based on the traditional statistical analysis method using the Weibull distribution function. For this scheme, the failure-grade index is defined, and a fuzzy-evaluation method is also proposed by comprehensively considering failure severity, failure maintenance, time, and cost; this is then combined with the time between failures to characterize the failure state. Based on the fuzzy failure data, an improved adaptive-failure small-sample-expansion method is proposed based on the classical bootstrap method and the deviation judgment between distributions of the original and newborn samples. Finally, a novel reliability-evaluation model, related to the failure grade and its membership degree, is established to quantify the reliability level of equipment more realistically. Example cases for three methods of the scheme (the failure-grade fuzzy-evaluation method, the sample-expansion method, and the reliability-evaluation modeling method) are presented, respectively, to validate the effectiveness and significance of the proposed reliability-evaluation technology. Full article
(This article belongs to the Special Issue Mathematical Applications in Industrial Engineering)
24 pages, 5022 KiB  
Article
Transfer Matrix Method for the Analysis of Multiple Natural Frequencies
by Jinghong Wang, Xiaoting Rui, Bin He, Xun Wang, Jianshu Zhang and Kai Xie
Mathematics 2024, 12(9), 1413; https://doi.org/10.3390/math12091413 - 06 May 2024
Abstract
Multiple natural frequencies may be encountered when analyzing the essential natural vibration of a symmetric mechanical system or sub-structure system or a system with special parameters. The transfer matrix method (TMM) is a useful tool for analyzing the natural vibration characteristics of mechanical [...] Read more.
Multiple natural frequencies may be encountered when analyzing the essential natural vibration of a symmetric mechanical system or sub-structure system or a system with special parameters. The transfer matrix method (TMM) is a useful tool for analyzing the natural vibration characteristics of mechanical or structural systems. It derives a nonlinear eigen-problem (NEP) in general, even a transcendental eigen-problem. This investigation addresses the NEP in TMM and proposes a novel method, called the determinant-differentiation-based method, for calculating multiple natural frequencies and determining their multiplicities. Firstly, the characteristic determinant is differentiated with respect to frequency, transforming the even multiple natural frequencies into the odd multiple zeros of the differentiation of the characteristic determinant. The odd multiple zeros of the first derivative of the characteristic determinant and the odd multiple natural frequencies can be obtained using the bisection method. Among the odd multiple zeros, the even multiple natural frequencies are picked out by the proposed judgment criteria. Then, the natural frequency multiplicities are determined by the higher-order derivatives of the characteristic determinant. Finally, several numerical simulations including the multiple natural frequencies show that the proposed method can effectively calculate the multiple natural frequencies and determine their multiplicities. Full article
(This article belongs to the Special Issue Advanced Computational Methods in Mechanics and Engineering)
Show Figures

Graphical abstract

18 pages, 2807 KiB  
Article
Learning the Hybrid Nonlocal Self-Similarity Prior for Image Restoration
by Wei Yuan, Han Liu, Lili Liang and Wenqing Wang
Mathematics 2024, 12(9), 1412; https://doi.org/10.3390/math12091412 - 06 May 2024
Abstract
As an immensely important characteristic of natural images, the nonlocal self-similarity (NSS) prior has demonstrated great promise in a variety of inverse problems. Unfortunately, most current methods utilize either the internal or the external NSS prior learned from the degraded image or training [...] Read more.
As an immensely important characteristic of natural images, the nonlocal self-similarity (NSS) prior has demonstrated great promise in a variety of inverse problems. Unfortunately, most current methods utilize either the internal or the external NSS prior learned from the degraded image or training images. The former is inevitably disturbed by degradation, while the latter is not adapted to the image to be restored. To mitigate such problems, this work proposes to learn a hybrid NSS prior from both internal images and external training images and employs it in image restoration tasks. To achieve our aims, we first learn internal and external NSS priors from the measured image and high-quality image sets, respectively. Then, with the learned priors, an efficient method, involving only singular value decomposition (SVD) and a simple weighting method, is developed to learn the HNSS prior for patch groups. Subsequently, taking the learned HNSS prior as the dictionary, we formulate a structural sparse representation model with adaptive regularization parameters called HNSS-SSR for image restoration, and a general and efficient image restoration algorithm is developed via an alternating minimization strategy. The experimental results indicate that the proposed HNSS-SSR-based restoration method exceeds many existing competition algorithms in PSNR and SSIM values. Full article
25 pages, 1041 KiB  
Article
Is There a Link between Remittances, Capital Formation, Structural Transformation and Economic Growth? A Dynamic Panel Analysis for Latin America under the PVAR Approach
by Eduardo Germán Zurita Moreano, María Gabriela González Bautista, Juan Pablo Vallejo Mata and Víctor Dante Ayaviri-Nina
Economies 2024, 12(5), 109; https://doi.org/10.3390/economies12050109 - 06 May 2024
Abstract
The literature has mainly focused on analyzing the relationship of remittances with economic growth and social welfare, neglecting more complex aspects where remittances can have relevant implications. To contribute to the literature, the objective of this research is to examine the dynamic relationship [...] Read more.
The literature has mainly focused on analyzing the relationship of remittances with economic growth and social welfare, neglecting more complex aspects where remittances can have relevant implications. To contribute to the literature, the objective of this research is to examine the dynamic relationship between remittances, capital formation, structural transformation and economic growth in 15 Latin American countries during the period 1996–2019. To meet the objective, a panel vector autoregressive regression (PVAR) model was estimated, focusing on the analysis of the impulse-response function and variance decomposition. The results show a positive effect of remittances on economic growth and capital formation and a negative effect of remittances on structural transformation for initial periods and positive for later periods, framing a non-linear relationship. In addition, it was determined that structural transformation does not have a significant impact on economic growth. Finally, it was found that capital formation has a partial positive effect on economic growth. It is concluded that public policies should generate support mechanisms for the efficient channeling of these resources so that they become engines of growth. Full article
Show Figures

Figure 1

Open Access Journals

Browse by Indexing Browse by Subject Selected Journals
Back to TopTop