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20 pages, 11335 KiB

Open AccessArticle

Design and Analysis of Tubular Transverse Flux Permanent Magnet Linear Motor

by Guopeng Sun, Mei Zhao, Jianjun Li, Tong Yao and Huaqiang Zhang

Energies 2024, 17(23), 6180; https://doi.org/10.3390/en17236180 (registering DOI) - 7 Dec 2024

The electrical load and the magnetic load of the transverse flux permanent magnet linear motor (TFPMLM) are decoupled from each other, which makes it easy to achieve modularization, and it has broad application prospects in the field of low speed and high thrust. [...] Read more.

The electrical load and the magnetic load of the transverse flux permanent magnet linear motor (TFPMLM) are decoupled from each other, which makes it easy to achieve modularization, and it has broad application prospects in the field of low speed and high thrust. Firstly, the topology structure of a cylindrical TFPMLM is proposed, and its working principle is introduced. Secondly, the basic electromagnetic performance of the motor is studied. Thirdly, the influence of the structural parameters on the flux linkage, back-EFM, and cogging force has been analyzed by the 3D finite element method (FEM). Then, the kriging agent model is constructed through the DOE experiment, and a set of size parameters with better performance are found by using a multi-objective genetic algorithm. Finally, the prototype and experimental setup have been developed. The calculated results and the measured results are in good agreement. Full article

(This article belongs to the Section F3: Power Electronics)

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13 pages, 18113 KiB

Open AccessArticle

First-Principles Study of Titanium-Doped B₇ Cluster for High Capacity Hydrogen Storage

by Haishen Huang, Guoxu Li, Zhenqiang Li, Tingyan Zhou, Ping Li, Xiude Yang and Bo Wu

Molecules 2024, 29(23), 5795; https://doi.org/10.3390/molecules29235795 (registering DOI) - 7 Dec 2024

Abstract

The geometrical structure, stability, electronic properties, and hydrogen storage capabilities of a titanium-doped B

_{7}

cluster was calculated using density functional theory computations. The results show that the TiB

_{7}

cluster is predicted to be stable under near-ambient conditions based on an ab [...] Read more.

The geometrical structure, stability, electronic properties, and hydrogen storage capabilities of a titanium-doped B

_{7}

cluster was calculated using density functional theory computations. The results show that the TiB

_{7}

cluster is predicted to be stable under near-ambient conditions based on an ab initio molecular dynamic simulation. The transition state analysis found that the H

_{2}

molecule can dissociate on the TIB

_{7}

cluster surface to form a hydride cluster. The Ti atom within the TiB

_{7}

cluster demonstrates an impressive capacity to adsorb up to five H

_{2}

molecules, achieving a peak hydrogen storage mass fraction of 7.5%. It is worth noting that the average adsorption energy of H

_{2}

molecules is 0.27–0.32 eV, which shows that these configurations are suited for reversible hydrogen storage under mild temperature and pressure regimes. In addition, calculations found that both polarization and hybridization mechanisms play pivotal roles in facilitating the adsorption of H

_{2}

molecules onto the TiB

_{7}

cluster. Our research results show that the TiB

_{7}

cluster has potential for hydrogen storage applications under near-ambient conditions. Full article

(This article belongs to the Special Issue Novel Two-Dimensional Energy-Environmental Materials)

17 pages, 15492 KiB

Open AccessArticle

ADAM10 Expression by Ameloblasts is Essential for Proper Enamel Formation

by Shifa Shahid, Yuanyuan Hu, Fatma Mohamed, Lara Rizzotto, Michelle C. Layana, Daniel T. Fleming, Petros Papagerakis, Brian L. Foster, James P. Simmer and John D. Bartlett

Int. J. Mol. Sci. 2024, 25(23), 13184; https://doi.org/10.3390/ijms252313184 (registering DOI) - 7 Dec 2024

Abstract

ADAM10 is a multi-functional proteinase that can cleave approximately 100 different substrates. Previously, it was demonstrated that ADAM10 is expressed by ameloblasts, which are required for enamel formation. The goal of this study was to determine if ADAM10 is necessary for enamel development. [...] Read more.

ADAM10 is a multi-functional proteinase that can cleave approximately 100 different substrates. Previously, it was demonstrated that ADAM10 is expressed by ameloblasts, which are required for enamel formation. The goal of this study was to determine if ADAM10 is necessary for enamel development. Deletion of Adam10 in mice is embryonically lethal and deletion of Adam10 from epithelia is perinatally lethal. We therefore deleted Adam10 from ameloblasts. Ameloblast-specific expression of the Tg(Amelx-iCre)872pap construct was confirmed. These mice were crossed with Adam10 floxed mice to generate Amelx-iCre; Adam10^fl/fl mice (Adam10 cKO). The Adam10 cKO mice had discolored teeth with softer than normal enamel. Notably, the Adam10 cKO enamel density and volume were significantly reduced in both incisors and molars. Moreover, the incisor enamel rod pattern became progressively more disorganized, moving from the DEJ to the outer enamel surface, and this disorganized rod structure created gaps and S-shaped rods. ADAM10 cleaves proteins essential for cell signaling and for enamel formation such as RELT and COL17A1. ADAM10 also cleaves cell-cell contacts such as E- and N-cadherins that may support ameloblast movement necessary for normal rod patterns. This study shows, for the first time, that ADAM10 expressed by ameloblasts is essential for proper enamel formation. Full article

(This article belongs to the Special Issue Molecular Metabolism of Ameloblasts in Tooth Development)

19 pages, 790 KiB

Open AccessReview

A Systematic Review of Ethical Leadership as a Panacea for Combating Sexual Harassment in Africa

by Ijeoma Gloria Ukeni

Adm. Sci. 2024, 14(12), 332; https://doi.org/10.3390/admsci14120332 (registering DOI) - 7 Dec 2024

Abstract

Sexual harassment is an ongoing baseness that should be non-existent at work. Such immoral behaviours have psychological, physical, and behavioural impacts on victims, with no organisational benefit. Hence, it is imperative that positive actions against sexual harassment are needed, and leaders have a [...] Read more.

Sexual harassment is an ongoing baseness that should be non-existent at work. Such immoral behaviours have psychological, physical, and behavioural impacts on victims, with no organisational benefit. Hence, it is imperative that positive actions against sexual harassment are needed, and leaders have a role to play. However, there are limited studies on how ethical leaders can contribute to the eradication process. This report, therefore, makes a compelling case for developing ethical leaders as champions against sexual harassment. It accentuates the positive effect of role-modelling ethical behaviours. Based on secondary data, traditional and systematic literature reviews were conducted on sexual harassment and ethical leadership in sub-Saharan Africa, respectively. The results of the thematic analysis showed that women are mostly the victims of sexual harassment due to the abuse of power and poor execution of harassment policies. The study offers laudable mechanisms such as the creation of an inclusive environment with zero tolerance for sexual harassment, the moral development of organisational members and the reorientation and support for victims. Given the ‘power distance’ culture of most African nations, the fight will be tough, but the benefits and prospects far outweigh the cost. Hence, recommendations and practical approaches to potential challenges are discussed. Full article

(This article belongs to the Special Issue Improving Ethical Leadership in Its Cultural Context: New Challenges and Prospects)

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24 pages, 7535 KiB

Open AccessArticle

Antioxidant and Ultrastructural Alterations in Wheat During Drought-Induced Leaf Senescence

by Turana Y. Isgandarova, Samira M. Rustamova, Durna R. Aliyeva, Fuad H. Rzayev, Eldar K. Gasimov and Irada M. Huseynova

Agronomy 2024, 14(12), 2924; https://doi.org/10.3390/agronomy14122924 (registering DOI) - 7 Dec 2024

Abstract

Wheat is one of the most important crops to ensure food production globally. Understanding the mechanism of leaf senescence in wheat plays a crucial role in improving its productivity and resilience under various stress scenarios. In this study, we investigated biochemical, functional, and [...] Read more.

Wheat is one of the most important crops to ensure food production globally. Understanding the mechanism of leaf senescence in wheat plays a crucial role in improving its productivity and resilience under various stress scenarios. In this study, we investigated biochemical, functional, and ultrastructural changes during leaf senescence in wheat genotypes with contrasting drought tolerance. For this, key parameters such as chlorophyll and total protein content, membrane stability, malondialdehyde level, and the activity of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, benzidine peroxidase, and catalase) were comparatively analyzed during both natural and drought-induced senescence. Additionally, the expression of superoxide dismutase isoform genes functioning in different cellular compartments was studied, alongside ultrastructural changes in flag leaves. The experiments involved genotypes of bread wheat (Triticum aestivum L.) and durum (Triticum durum Desf.) wheat. The plants were grown in controlled environment chambers under control and drought conditions using a completely randomized design. After the booting stage, irrigation was discontinued for drought-treated plants. Flag leaves were sampled at 7, 14, 21, 28, and 35 days after anthesis. Drought-tolerant genotypes exhibited slower chlorophyll degradation, lower lipid peroxidation, enhanced membrane stability, and stronger antioxidant responses, allowing them to maintain cellular function longer, whereas sensitive genotypes showed accelerated leaf senescence. Transcript levels of FeSOD increased significantly post-flowering but declined as senescence progressed, while MnSOD expression exhibited a rise towards the later stages of ontogenesis across all studied genotypes. Ultrastructural analysis revealed progressive damage to chloroplast membranes, thylakoid structures, and mesophyll cell walls under stress conditions, particularly in sensitive genotypes. These findings contribute to a deeper understanding of the physiological and molecular responses of wheat to drought stress, offering potential targets for improving crop performance in water-limited environments. Full article

(This article belongs to the Section Plant-Crop Biology and Biochemistry)

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21 pages, 5990 KiB

Open AccessReview

Impacts of Air Pollution on Community Well-Being in the Tourism Sector: A Comprehensive Literature Review

by Ioan Bogdan Bacos, Cristina Veres, Petru Alexandru Curta, Manuela Rozalia Gabor and Flavia Dana Oltean

Sustainability 2024, 16(23), 10752; https://doi.org/10.3390/su162310752 (registering DOI) - 7 Dec 2024

Abstract

This critical review examines the interplay between air pollution and community well-being within the tourism industry. Utilizing a systematic literature review methodology, the study focuses on three domains: air quality, tourism, and sustainability. Employing VOSviewer for bibliometric analysis, the research identifies key themes [...] Read more.

This critical review examines the interplay between air pollution and community well-being within the tourism industry. Utilizing a systematic literature review methodology, the study focuses on three domains: air quality, tourism, and sustainability. Employing VOSviewer for bibliometric analysis, the research identifies key themes and trends. The findings reveal that air pollution, particularly in urban tourist destinations, negatively impacts tourist behavior, reduces visitor numbers, and threatens the economic sustainability of tourism. Additionally, it highlights health risks to both tourists and local communities, underscoring the need for adaptive strategies and sustainable practices. The study prioritizes articles employing statistical methods and incorporates geographic visualizations using GeoPandas and Matplotlib to illustrate research distribution. By synthesizing the existing literature, this review emphasizes the importance of effective policies that balance tourism growth with environmental protection amidst escalating ecological challenges. Full article

(This article belongs to the Special Issue Sustainable Development in Different Fields of Tourism)

20 pages, 13199 KiB

Open AccessArticle

Peripherally Restricted Activation of Opioid Receptors Influences Anxiety-Related Behaviour and Alters Brain Gene Expression in a Sex-Specific Manner

by Nabil Parkar, Wayne Young, Trent Olson, Charlotte Hurst, Patrick Janssen, Nick J. Spencer, Warren C. McNabb and Julie E. Dalziel

Int. J. Mol. Sci. 2024, 25(23), 13183; https://doi.org/10.3390/ijms252313183 (registering DOI) - 7 Dec 2024

Abstract

Although effects of stress-induced anxiety on the gastrointestinal tract and enteric nervous system (ENS) are well studied, how ENS dysfunction impacts behaviour is not well understood. We investigated whether ENS modulation alters anxiety-related behaviour in rats. We used loperamide, a potent μ-opioid receptor [...] Read more.

Although effects of stress-induced anxiety on the gastrointestinal tract and enteric nervous system (ENS) are well studied, how ENS dysfunction impacts behaviour is not well understood. We investigated whether ENS modulation alters anxiety-related behaviour in rats. We used loperamide, a potent μ-opioid receptor agonist that does not cross the blood–brain barrier, to manipulate ENS function and assess changes in behaviour, gut and brain gene expression, and microbiota profile. Sprague Dawley (male/female) rats were acutely dosed with loperamide (subcutaneous) or control solution, and their behavioural phenotype was examined using open field and elevated plus maze tests. Gene expression in the proximal colon, prefrontal cortex, hippocampus, and amygdala was assessed by RNA-seq and caecal microbiota composition determined by shotgun metagenome sequencing. In female rats, loperamide treatment decreased distance moved and frequency of supported rearing, indicating decreased exploratory behaviour and increased anxiety, which was associated with altered hippocampal gene expression. Loperamide altered proximal colon gene expression and microbiome composition in both male and female rats. Our results demonstrate the importance of the ENS for communication between gut and brain for normo-anxious states in female rats and implicate corticotropin-releasing hormone and gamma-aminobutyric acid gene signalling pathways in the hippocampus. This study also sheds light on sexually dimorphic communication between the gut and the brain. Microbiome and colonic gene expression changes likely reflect localised effects of loperamide related to gut dysmotility. These results suggest possible ENS pharmacological targets to alter gut to brain signalling for modulating mood. Full article

(This article belongs to the Special Issue Interactions between the Nervous System and Gastrointestinal Motility)

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12 pages, 1186 KiB

Open AccessArticle

Toward Classification of Fish Meat Using Fluorescence Excitation–Emission Matrix and Multivariate Statistics

by Md. Mizanur Rahman, Mario Shibata, Mst. Nazira Akhter Rithu and Emiko Okazaki

Fishes 2024, 9(12), 500; https://doi.org/10.3390/fishes9120500 (registering DOI) - 7 Dec 2024

Abstract

Frequent intentional mislabeling of particular fish and fish products, such as the sale of frozen and thawed fish instead of fresh fish, occurs on all continents. Therefore, two studies were conducted to classify fish meat using excitation–emission matrix (EEM) nondestructively. The first study [...] Read more.

Frequent intentional mislabeling of particular fish and fish products, such as the sale of frozen and thawed fish instead of fresh fish, occurs on all continents. Therefore, two studies were conducted to classify fish meat using excitation–emission matrix (EEM) nondestructively. The first study assessed EEM for differentiation between fresh and frozen–thawed spotted mackerel fillets. Fresh fillets were yielded with different post-mortem freshness variations (ice storage for 0–40 h). The right-side fillets were used as fresh fillets, whereas the left-side fillets were frozen and stored at −30 °C for three months, then thawed at 4 °C. Subsequently, EEM acquisition and chemical analyses were performed. Results of principal component analysis (PCA) of EEM spectra showed clear discrimination between fresh and frozen–thawed meat of fish fillet. In the second study, post-mortem freshness variations in four fish species (horse mackerel, spotted mackerel, cod, and flounder) were simulated by ice storage (0–48 h) and subsequent freezing. PCA of the EEM demonstrated a clear distinction among the fish meat categories, which was also revealed from the freshness data of chemical analysis. Results show that this novel method can be used to monitor fishery product authenticity. Full article

27 pages, 799 KiB

Open AccessArticle

A Hesitation-Associated Multi-Attribute Decision-Making Method Based on Generalized Interval-Valued Hesitation Fuzzy Weighted Heronian Averaging Operator

by Jiayou Shen, Nan Yang and Hejun Liang

Mathematics 2024, 12(23), 3857; https://doi.org/10.3390/math12233857 (registering DOI) - 7 Dec 2024

Abstract

In multi-attribute decision making (MADM), complex situations often arise where decision attributes are interval-valued hesitant fuzzy numbers (IVHFNs) and the attributes are interrelated. Traditional decision-making methods may be ineffective in handling such cases, highlighting the practical importance of seeking more effective approaches. Therefore, [...] Read more.

In multi-attribute decision making (MADM), complex situations often arise where decision attributes are interval-valued hesitant fuzzy numbers (IVHFNs) and the attributes are interrelated. Traditional decision-making methods may be ineffective in handling such cases, highlighting the practical importance of seeking more effective approaches. Therefore, finding a more effective decision-making approach has important practical significance. By combining the theories of Archimedean S-norms and T-norms, we innovatively propose a multi-attribute decision-making method based on the generalized interval-valued hesitant fuzzy weighted Heronian mean (GIVHFWHM) operator to address the aforementioned issues. Initially, based on the operational laws of IVHFNs and the Heronian mean (HM) operator, we introduce the generalized interval-valued hesitant fuzzy Heronian mean (GIVHFHM) operator and the GIVHFWHM operator. We then examine properties of the GIVHFHM operator, including permutation invariance, idempotency, monotonicity, boundedness, and parameter symmetry. A multi-attribute decision-making model is constructed based on the GIVHFWHM operator. Finally, we validate the proposed model through numerical experiments in MADM. The results demonstrate that the new decision-making method, based on the GIVHFWHM operator, is feasible and effective in handling multi-attribute decision problems involving IVHFNs with interdependent attributes. This approach provides a novel perspective and method for solving MADM problems under interval-valued hesitant fuzzy conditions with interdependent attributes. It enriches the theoretical framework of multi-attribute hesitant decision models and expands the application of the Heronian mean operator within interval-valued hesitant fuzzy environments. This methodology assists decision makers in making more accurate decisions within complex decision-making contexts, enhancing both the scientific rigor and reliability of decision-making processes. Full article

(This article belongs to the Special Issue Advances and Applications on Fuzzy Logic for Decision Making Processes)

17 pages, 7735 KiB

Open AccessArticle

A Comparative Performance Evaluation of Mainstream Multiphase Models for Aerated Flow on Stepped Spillways

by Fan Yang, Zongshi Dong, Jinrong Da and Junxing Wang

Water 2024, 16(23), 3529; https://doi.org/10.3390/w16233529 (registering DOI) - 7 Dec 2024

Abstract

A systematic comparative evaluation of mainstream multiphase models for specific hydraulic structures is essential to investigate aerated flow characteristics and promote the models’ application. However, such evaluations remain scarce. In this paper, four multiphase models, namely the VOF, Mixture, and Eulerian models in [...] Read more.

A systematic comparative evaluation of mainstream multiphase models for specific hydraulic structures is essential to investigate aerated flow characteristics and promote the models’ application. However, such evaluations remain scarce. In this paper, four multiphase models, namely the VOF, Mixture, and Eulerian models in Ansys Fluent and the aerated flow model in FLOW-3D (AFM-F3D), were comparatively introduced and tested for the aerated flow over stepped spillways. Simulation results, including water surface profiles, inception points of aeration, air concentrations, velocities, and turbulent kinetic energies from four models, are compared with each other and with available experimental data. It is discovered that both the VOF and Mixture models fail to reproduce the self-aeration and subsequent downward transport phenomenon. In contrast, AFM-F3D and the Eulerian models predict reliable aerated water surface profiles. AFM-F3D and the Eulerian model demonstrate superior performance in velocity and air concentration calculations, respectively. Based on overall performance, the Eulerian model is recommended for simulating aerated stepped spillway flows. These insights provide valuable guidance for selecting appropriate multiphase models based on specific engineering requirements. Full article

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19 pages, 1731 KiB

Open AccessArticle

From Olive Oil Lovers to Mediterranean Diet Lifestyle Followers: Consumption Pattern Segmentation in the Portuguese Context

by Valentina Chkoniya, Maria João Gregório, Sandra Filipe and Pedro Graça

Nutrients 2024, 16(23), 4235; https://doi.org/10.3390/nu16234235 (registering DOI) - 7 Dec 2024

Abstract

The Mediterranean Diet (MedDiet) is considered an Intangible Cultural Heritage by UNESCO; it is also the world’s most evidence-based eating pattern for promoting health and longevity. This study aims to investigate consumer segmentation based on consumption patterns and identify barriers to adherence to [...] Read more.

The Mediterranean Diet (MedDiet) is considered an Intangible Cultural Heritage by UNESCO; it is also the world’s most evidence-based eating pattern for promoting health and longevity. This study aims to investigate consumer segmentation based on consumption patterns and identify barriers to adherence to MedDiet. Data were collected in 2020 by telephonic survey based on PREDIMED, using a quota sampling technique by socio-demographic variables, such as gender, age, and regional representation of the Portuguese population. The final sample was composed of a total of 1000 respondents. The main results show that regardless of the awareness of the MedDiet (62%), Portugal witnessed a loss of the traditional MedDiet, with the exception of the stand-out statistic that 95% of respondents still use of olive oil as the main culinary fat. Five segments were identified: (1) MedDiet lifestyle followers (11%), (2) olive oil lovers (20%), (3) low-sugar diet foods seekers (11%), (4) healthy and balanced diet seekers (28%), and (5) low-fat diet foods seekers (30%). The main barriers to adhering to the MedDiet include lack of knowledge about the MedDiet, education level, financial comfort, and specific food preference, which by segment are: (1) being passionate about soda drinks, (2) an excess of sweets, (3) low level of pasta consumption, and a (5) lack of fruit, vegetables, and legumes. Segment (4) holds a leading position in MedDiet adherence. The main obstacle to consuming fish is its high price, taste, and challenges in cooking it. When it comes to bread and oleaginous nuts, the belief that these foods are “fattening” reduces consumption. Results help to tailor education strategy and increase adherence to the Mediterranean lifestyle. Full article

(This article belongs to the Special Issue Mediterranean Diet, Plant-Based Diet, Low-Fat Diet and Human Health)

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25 pages, 4786 KiB

Open AccessArticle

Air Pollution Measurement and Dispersion Simulation Using Remote and In Situ Monitoring Technologies in an Industrial Complex in Busan, South Korea

by Naghmeh Dehkhoda, Juhyeon Sim, Juseon Shin, Sohee Joo, Sung Hwan Cho, Jeong Hun Kim and Youngmin Noh

Sensors 2024, 24(23), 7836; https://doi.org/10.3390/s24237836 (registering DOI) - 7 Dec 2024

Abstract

Rapid industrialization and the influx of human resources have led to the establishment of industrial complexes near urban areas, exposing residents to various air pollutants. This has led to a decline in air quality, impacting neighboring residential areas adversely, which highlights the urgent [...] Read more.

Rapid industrialization and the influx of human resources have led to the establishment of industrial complexes near urban areas, exposing residents to various air pollutants. This has led to a decline in air quality, impacting neighboring residential areas adversely, which highlights the urgent need to monitor air pollution in these areas. Recent advancements in technology, such as Solar Occultation Flux (SOF) and Sky Differential Optical Absorption Spectroscopy (SkyDOAS) used as remote sensing techniques and mobile extraction Fourier Transform Infrared Spectrometry (MeFTIR) used as an in situ technique, now offer enhanced precision in estimating the pollutant emission flux and identifying primary sources. In a comprehensive study conducted in 2020 in the Sinpyeong Jangrim Industrial Complex in Busan City, South Korea, a mobile laboratory equipped with SOF, SkyDOAS, and MeFTIR technologies was employed to approximate the emission flux of total alkanes, sulfur dioxide (SO₂), nitrogen dioxide (NO₂), formaldehyde (HCHO), and methane (CH₄). Using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) diffusion model, pollutant dispersion to residential areas was simulated. The highest average daily emission flux was observed for total alkanes, with values of 69.9 ± 71.6 kg/h and 84.1 ± 85.8 kg/h in zones S₁ and S₂ of the Sinpyeong Jangrim Industrial Complex, respectively. This is primarily due to the prevalence of metal manufacturing and mechanical equipment industries in the area. The HYSPLIT diffusion model confirmed elevated pollution levels in residential areas located southeast of the industrial complex, underscoring the influence of the dominant northwesterly wind direction and wind speed on pollutant dispersion. This highlights the urgent need for targeted interventions to address and mitigate air pollution in downwind residential areas. The total annual emission fluxes were estimated at 399,984 kg/yr and 398,944 kg/yr for zones S₁ and S₂, respectively. A comparison with the Pollutant Release and Transfer Registers (PRTRs) survey system revealed that the total annual emission fluxes in this study were approximately 24.3 and 4.9 times higher than those reported by PRTRs. This indicates a significant underestimation of the impact of small businesses on local air quality, which was not accounted for in the PRTR survey system. Full article

(This article belongs to the Special Issue Remote Sensing in Atmospheric Measurements)

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16 pages, 26890 KiB

Open AccessArticle

Spatiotemporal Multivariate Weather Prediction Network Based on CNN-Transformer

by Ruowu Wu, Yandan Liang, Lianlei Lin and Zongwei Zhang

Sensors 2024, 24(23), 7837; https://doi.org/10.3390/s24237837 (registering DOI) - 7 Dec 2024

Abstract

Weather prediction is of great significance for human daily production activities, global extreme climate prediction, and environmental protection of the Earth. However, the existing data-based weather prediction methods cannot adequately capture the spatial and temporal evolution characteristics of the target region, which makes [...] Read more.

Weather prediction is of great significance for human daily production activities, global extreme climate prediction, and environmental protection of the Earth. However, the existing data-based weather prediction methods cannot adequately capture the spatial and temporal evolution characteristics of the target region, which makes it difficult for the existing methods to meet practical application requirements in terms of efficiency and accuracy. Changes in weather involve both strongly correlated spatial and temporal continuation relationships, and at the same time, the variables interact with each other, so capturing the dynamic correlations among space, time, and variables is particularly important for accurate weather prediction. Therefore, we designed a spatiotemporal coupled prediction network based on convolution and Transformer for weather prediction from the perspective of multivariate spatiotemporal fields. First, we designed a spatial attention encoder-decoder to comprehensively explore spatial representations for extracting and reconstructing spatial features. Then, we designed a multi-scale spatiotemporal evolution module to obtain the spatiotemporal evolution patterns of weather using inter- and intra-frame computations. After that, in order to ensure that the model has better prediction ability for global and local hotspot areas, we designed a composite loss function based on MSE and SSIM to focus on the global and structural distribution of weather to achieve more accurate multivariate weather prediction. Finally, we demonstrated the excellent effect of STWPM in multivariate spatiotemporal field weather prediction by comprehensively evaluating the proposed algorithm with classical algorithms on the ERA5 dataset in a global region. Full article

(This article belongs to the Special Issue Machine Learning and Deep Learning in Image/Video Processing and Sensing)

14 pages, 1633 KiB

Open AccessArticle

Risk Factors for Long-Term Nutritional Disorders One Year After COVID-19: A Post Hoc Analysis of COVID-19 Recovery Study II

by Keiichiro Kawabata, Kensuke Nakamura, Naoki Kanda, Muneaki Hemmi, Shinya Suganuma, Yoko Muto, Arisa Iba, Miyuki Hori, Mariko Hosozawa and Hiroyasu Iso

Nutrients 2024, 16(23), 4234; https://doi.org/10.3390/nu16234234 (registering DOI) - 7 Dec 2024

Abstract

Background/Objectives: COVID-19 patients develop various clinical symptoms, including malnutrition. However, the risk factors for long-term nutritional disorders remain unclear. Identifying these factors is crucial for preventing nutritional disorders by initiating early nutritional interventions. Methods: This was a post hoc analysis of [...] Read more.

Background/Objectives: COVID-19 patients develop various clinical symptoms, including malnutrition. However, the risk factors for long-term nutritional disorders remain unclear. Identifying these factors is crucial for preventing nutritional disorders by initiating early nutritional interventions. Methods: This was a post hoc analysis of COVID-19 Recovery Study II (CORESII). The study included adult patients hospitalized for COVID-19 and discharged from the hospital. Information, including post-COVID-19 symptoms one month after onset and changes in daily life during the first year, was collected using a self-administered questionnaire sent one year after hospital discharge. We examined the association between baseline characteristics, disease severity, and symptoms that persisted one month after onset with malnutrition disorders one year after onset, defined as a Malnutrition Universal Screening Tool score ≥1, using a logistic regression analysis. Results: A total of 1081 patients (mean age of 56.0 years; 34% females; 38% admitted to the intensive care unit) were analyzed. Of these patients, 266 patients (24.6%) had malnutrition one year after onset. In a multivariable logistic regression analysis using variables that were significant in a univariate logistic regression analysis, the following factors were independently associated with malnutrition: BMI < 18.5 kg/m² (odds ratio [95% confidence interval (CI)], 48.9 [14.3–168]), 18.5 ≤ BMI ≤ 20 (10.5 [5.89–18.8]), 30 < BMI (2.64 [1.84–3.75]), length of hospital stay (1.01 [1.00–1.02]), maintenance dialysis (3.19 [1.19–8.61]), and difficulty concentrating one month after onset (1.73 [1.07–2.79]). Conclusions: Being underweight or obese, prolonged hospitalization, maintenance dialysis, and difficulty concentrating one month after onset were associated with a risk of malnutrition one year post-illness. Patients with these factors may be at a high risk of long-term nutritional disorders. Full article

(This article belongs to the Special Issue The Importance of a Clinical Diet and Nutritional Management for Patients)

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25 pages, 2524 KiB

Open AccessReview

Interplay Between Metabolic Pathways and Increased Oxidative Stress in Human Red Blood Cells

by Sara Spinelli, Angela Marino, Rossana Morabito and Alessia Remigante

Cells 2024, 13(23), 2026; https://doi.org/10.3390/cells13232026 (registering DOI) - 7 Dec 2024

Abstract

Red blood cells (RBCs) are highly specialized cells with a limited metabolic repertoire. However, it has been demonstrated that metabolic processes are affected by the production of reactive oxygen species (ROS), and critical enzymes allied to metabolic pathways can be impaired by redox [...] Read more.

Red blood cells (RBCs) are highly specialized cells with a limited metabolic repertoire. However, it has been demonstrated that metabolic processes are affected by the production of reactive oxygen species (ROS), and critical enzymes allied to metabolic pathways can be impaired by redox reactions. Thus, oxidative stress-induced alternations in the metabolic pathways can contribute to cell dysfunction of human RBCs. Herein, we aim to provide an overview on the metabolic pathways of human RBCs, focusing on their pathophysiological relevance and their regulation in oxidative stress-related conditions. Full article

(This article belongs to the Special Issue Cellular and Molecular Mechanisms in Oxidative Stress-Related Chronic Diseases)

22 pages, 2291 KiB

Open AccessArticle

Analysing Digital Engagement Patterns: A Machine Learning Investigation into Social Anxiety Among Adolescents with ADHD

by Roxana Șipoș, Tudor Văidean, Andreea-Marlena Răpciuc, Costina-Ruxandra Poetar and Elena Predescu

J. Clin. Med. 2024, 13(23), 7461; https://doi.org/10.3390/jcm13237461 (registering DOI) - 7 Dec 2024

Abstract

Background: The relationship between screen time and mental health among adolescents, particularly those identified as “digital natives”, has become increasingly pertinent, especially in the context of heightened digital engagement during the COVID-19 pandemic. This study aims to examine the associations between digital engagement [...] Read more.

Background: The relationship between screen time and mental health among adolescents, particularly those identified as “digital natives”, has become increasingly pertinent, especially in the context of heightened digital engagement during the COVID-19 pandemic. This study aims to examine the associations between digital engagement patterns, ADHD severity, and anxiety symptoms in adolescents aged 11–18. Methods: A cross-sectional observational study was conducted with a sample of 97 adolescents diagnosed with ADHD. Participants completed validated questionnaires assessing daily digital activities and anxiety symptoms while caregivers provided additional contextual information. Data were analyzed using Random Forest regression to identify relationships between screen time, ADHD severity, and anxiety symptoms. Results: The findings indicate an average screen time of 6.6 h on weekdays and 8.1 h on weekends, with social media emerging as the primary activity, particularly among female participants. Notable gender differences were identified, with family dynamics influencing digital engagement; family disputes had a more significant impact on girls than boys. Furthermore, specific anxiety traits, i.e., physical symptoms and harm avoidance, significantly predicted time spent on social media across all genders considered in the study, while others, namely social anxiety and separation anxiety, were less valuable. Conclusions: This study highlights the complex interplay between screen time, ADHD, and anxiety symptoms in adolescents. These findings underscore the importance of tailored interventions that address the nuanced relationships between digital engagement and mental health in this population, warranting further research to develop effective management strategies. Full article

(This article belongs to the Special Issue Substance and Behavioral Addictions: Prevention and Diagnosis)

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26 pages, 8783 KiB

Open AccessReview

Intricate Structure–Function Relationships: The Case of the HtrA Family Proteins from Gram-Negative Bacteria

by Urszula Zarzecka and Joanna Skorko-Glonek

Int. J. Mol. Sci. 2024, 25(23), 13182; https://doi.org/10.3390/ijms252313182 (registering DOI) - 7 Dec 2024

Abstract

Proteolytic enzymes play key roles in living organisms. Because of their potentially destructive action of degrading other proteins, their activity must be very tightly controlled. The evolutionarily conserved proteins of the HtrA family are an excellent example illustrating strategies for regulating enzymatic activity, [...] Read more.

Proteolytic enzymes play key roles in living organisms. Because of their potentially destructive action of degrading other proteins, their activity must be very tightly controlled. The evolutionarily conserved proteins of the HtrA family are an excellent example illustrating strategies for regulating enzymatic activity, enabling protease activation in response to an appropriate signal, and protecting against uncontrolled proteolysis. Because HtrA homologs play key roles in the virulence of many Gram-negative bacterial pathogens, they are subject to intense investigation as potential therapeutic targets. Model HtrA proteins from bacterium Escherichia coli are allosteric proteins with reasonably well-studied properties. Binding of appropriate ligands induces very large structural changes in these enzymes, including changes in the organization of the oligomer, which leads to the acquisition of the active conformation. Properly coordinated events occurring during the process of HtrA activation ensure proper functioning of HtrA and, consequently, ensure fitness of bacteria. The aim of this review is to present the current state of knowledge on the structure and function of the exemplary HtrA family proteins from Gram-negative bacteria, including human pathogens. Special emphasis is paid to strategies for regulating the activity of these enzymes. Full article

(This article belongs to the Special Issue Mechanism of Enzyme Catalysis: When Structure Meets Function)

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20 pages, 3984 KiB

Open AccessArticle

A UV-Protective Textile Coating Based on Recycled Poly(vinyl butyral) (PVB): A New Life for a Waste Polymer

by Noemi Cei, Ilaria Canesi, Stefano Nejrotti, Giorgia Montalbano, Hamideh Darjazi, Alessandro Piovano, Matteo Bonomo, Alberto Fina, Beatriz Yecora, Angelica Perez, Claudia Barolo, Claudio Gerbaldi and Daniele Spinelli

Polymers 2024, 16(23), 3439; https://doi.org/10.3390/polym16233439 (registering DOI) - 7 Dec 2024

Abstract

Polyvinyl butyral (PVB) is a high-performance thermoplastic polymer, commonly used as an interlayer material in laminated safety glass for the automotive and architectural sectors. Currently, there is no end-of-life cycle program for a substantial amount of PVB film, which mainly ends up in [...] Read more.

Polyvinyl butyral (PVB) is a high-performance thermoplastic polymer, commonly used as an interlayer material in laminated safety glass for the automotive and architectural sectors. Currently, there is no end-of-life cycle program for a substantial amount of PVB film, which mainly ends up in landfills. According to a circular approach, PVB can be revalorized after efficient separation and recovery from glass. Thus, the aim of this work was to develop functional coatings for textile applications using recycled PVB (re-PVB), also in combination with an organic UV absorber, to enable the production of UV-protective final coated fabrics. The re-PVB-coated fabrics were obtained through an industrially scalable spraying process (leading to an average weight increase of 20 ± 3 wt.%), and the effectiveness of the application was evaluated according to different characterization techniques, such as FT-IR (Fourier transform–infrared) spectroscopy, SEM (scanning electron microscope), a washing test, a mechanical test, a thermo-physiological test, and the ultraviolet protection factor (UPF). Based on the results, the re-PVB-coated fabrics appeared stable upon washing (with a negligible weight loss compared to the average amount of coating) and effective in UV protection (with a final UPF being four times higher and a reduced UVA transmittance from 2.0% to 0.6%). Full article

(This article belongs to the Collection Progress in Polymer Applications)

14 pages, 11343 KiB

Open AccessArticle

Study of the Shear Strength Model of Unsaturated Soil in the Benggang Area of Southern China

by Maojin Yang, Nanbo Cen, Zumei Wang, Bifei Huang, Jinshi Lin, Fangshi Jiang, Yanhe Huang and Yue Zhang

Water 2024, 16(23), 3528; https://doi.org/10.3390/w16233528 (registering DOI) - 7 Dec 2024

Abstract

Benggangs are a unique type of soil erosion commonly found in southern China, with the gully wall being the most dynamic component of the Benggang system and is crucial for assessing its overall progression. The unsaturated shear strength of soil in Benggang areas [...] Read more.

Benggangs are a unique type of soil erosion commonly found in southern China, with the gully wall being the most dynamic component of the Benggang system and is crucial for assessing its overall progression. The unsaturated shear strength of soil in Benggang areas is a key factor influencing the stability of the gully wall. However, quantitative analyses of the unsaturated shear strength in the gully walls of Benggangs remain limited. In this study, the soil–water characteristic curves (SWCC) and shear strengths of undisturbed soil samples from four different soil layers in the gully wall of Benggang were measured using a pressure membrane meter and a quadruple direct shear apparatus. The results revealed that the water holding capacity of the soil decreased gradually with increasing matrix suction, and the order of the water holding capacity was the sandy soil layer > transition layer > laterite layer > clastic layer. With an increasing soil water content (SWC), the shear strength, cohesion (c), and internal friction angle (φ) of the four soil layers decreased significantly, and the φ showed a power function decreasing curve (p < 0.05), whereas c in the laterite layer and transition layer exhibited a power function decreasing curve (p < 0.01). The c of the sandy soil layer and clastic layer decreased linearly and logarithmically (p < 0.01) with increasing SWC, respectively. The unsaturated shear strength model for the four soil layers was developed based on the Vanapalli model. The root mean square error (RMSE) of the simulated and measured values was less than 29.349, while the Nash–Sutcliffe efficiency (NSE) and R² values were greater than 0.638 and 0.788, respectively. The model can be used to analyze and predict the unsaturated shear strength in different layers of Benggang gully walls, providing a theoretical foundation for studying the erosion mechanisms of Benggangs. Full article

(This article belongs to the Section Soil and Water)

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16 pages, 8137 KiB

Open AccessArticle

On Large Amplitude Vibrations of the Softening Duffing Oscillator at Low Excitation Frequencies—Some Fundamental Considerations

by Utz von Wagner, Lukas Lentz, Hannes Dänschel and Nils Gräbner

Appl. Sci. 2024, 14(23), 11411; https://doi.org/10.3390/app142311411 (registering DOI) - 7 Dec 2024

Abstract

The Duffing equation containing a cubic nonlinearity is probably the most popular example of a nonlinear oscillator. For its harmonically excited, slightly damped, and softening version, stationary large amplitude solutions at subcritical excitation frequencies are obtained when standard semi-analytical methods like Harmonic Balance [...] Read more.

The Duffing equation containing a cubic nonlinearity is probably the most popular example of a nonlinear oscillator. For its harmonically excited, slightly damped, and softening version, stationary large amplitude solutions at subcritical excitation frequencies are obtained when standard semi-analytical methods like Harmonic Balance or Perturbation Analysis are applied. These solutions have the shape of a nose in the amplitude-frequency diagram. In prior work, it has been observed that these solutions may contain large errors and that high ansatz orders may be necessary when applying the Harmonic Balance or other semi-analytical methods to make them converge. Some of these solutions are observed to be asymptotically stable, while in most cases, they are unstable. The current paper aims to give a descriptive explanation for this behavior of the nose solutions, which is mainly related to the exact solution of the free undamped vibrations. Based on this, approximations of the nose solutions are calculated with a procedure combining properties of Perturbation Analysis and Harmonic Balance. Therein, the exact solution of the free undamped vibrations is taken as the zeroth approximation, while higher-order solution parts are calculated by balancing the harmonics, and the phase shift of the zeroth approximation is calculated by a residuum minimization. This method just requires the solution of a system of linear algebraic equations, while systems of nonlinear algebraic equations have to be solved in the case of directly applying Harmonic Balance. Full article

(This article belongs to the Special Issue Phenomena in Nonlinear Dynamical Systems: Theory and Application)

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26 pages, 17697 KiB

Open AccessArticle

Study on Spatial Differentiation Characteristics and Driving Mechanism of Sustainable Utilization of Cultivated Land in Tarim River Basin

by Yang Sheng, Weizhong Liu and Hailiang Xu

Land 2024, 13(12), 2122; https://doi.org/10.3390/land13122122 (registering DOI) - 7 Dec 2024

Abstract

The sustainable utilization of cultivated land is a crucial prerequisite for ensuring food security and achieving sustainable socioeconomic development. This study employed a dataset to evaluate sustainable land use and utilized a combination of multi-factor comprehensive evaluation models, structural equation modeling, geographically weighted [...] Read more.

The sustainable utilization of cultivated land is a crucial prerequisite for ensuring food security and achieving sustainable socioeconomic development. This study employed a dataset to evaluate sustainable land use and utilized a combination of multi-factor comprehensive evaluation models, structural equation modeling, geographically weighted regression, and Pearson correlation analysis to systematically investigate the overall level, spatial differentiation characteristics, and driving mechanisms of sustainable cultivated land utilization in the Tarim River Basin. Additionally, we compared and tested three spatial interpolation methods using high-resolution data to address the modifiable areal unit problem (MAUP) and enhance the quality of spatial predictions for cultivated land utilization, ultimately identifying inverse distance weighting (IDW) as the optimal method. The results indicate the following: (1) The level of sustainable cultivated land utilization is moderately high, with an average index of 0.581, exhibiting a “U-shaped” trend from the upper to lower reaches of the Tarim River Basin. The highest levels are found in the Kashgar River–Yarkant River Basin, followed by the Hotan River Basin and the Kaidu–Peacock River Basin, while the mainstream area has the lowest levels. (2) The relationships among various cultivated land environmental systems and sustainability demonstrate distinct response characteristics and spatial differentiation patterns. Cultivated land use and management exert the most significant influence on sustainability, followed by soil quality and water resource systems, with climatic factors having the least impact. The effects of each system reveal inverted “U”, inverted “N”, “U”, and “W” patterns from the lower reaches to the upper reaches, respectively. (3) As the complexity of interactions and integrative mechanisms within the regional cultivated land system increases, the sensitivity and vulnerability of the system also rise, resulting in lower levels of sustainable utilization. (4) Based on the current challenges facing the cultivated land environmental system and the primary mechanisms influencing its sustainability, we propose regulatory measures focused on “suitable consolidation”, “suitable resting”, and “suitable planting”. These findings provide valuable insights for formulating differentiated land protection strategies, policies, and spatial planning initiatives. Full article

(This article belongs to the Special Issue Land Resource Assessment)

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15 pages, 1645 KiB

Open AccessArticle

Effects of Explosive vs. Strength Resistance Training on Plantar Flexor Neuromuscular and Functional Capacities in Institutionalized Older Adults: A Randomized Controlled Trial

by Elmoetez Magtouf, Nicolas Peyrot, Yosra Cherni, Oussema Gaied Chortane, Jonathan Jolibois, Abderrahmane Rahmani and Wael Maktouf

J. Funct. Morphol. Kinesiol. 2024, 9(4), 261; https://doi.org/10.3390/jfmk9040261 (registering DOI) - 7 Dec 2024

Abstract

Objectives: To compare the effects of explosive and strength resistance training on neuromuscular and functional parameters in older adults and to analyze the relationship between changes in walking speed and improvements in plantar flexor (PF) neuromuscular parameters following interventions. Methods: In total, 40 [...] Read more.

Objectives: To compare the effects of explosive and strength resistance training on neuromuscular and functional parameters in older adults and to analyze the relationship between changes in walking speed and improvements in plantar flexor (PF) neuromuscular parameters following interventions. Methods: In total, 40 participants were randomly assigned to either an explosive resistance training group (EXG, n = 18; age = 80.41 ± 10.12 years; body mass index = 22.89 ± 2.77 kg/m²) or a strength resistance training group (STG, n = 22; age = 82.89 ± 5.32 years; body mass index = 23.81 ± 3.45 kg/m²). Both groups participated in the same PF resistance training regimen (three sessions per week for 12 weeks), engaging in identical exercises. However, EXG performed three to five sets of 12 to 14 repetitions at 40% to 45% of one-maximal repetition with a rapid concentric phase and a 3 s eccentric phase, while the STG performed three to four sets of 6 to 7 repetitions at 80% to 85% of one-maximal repetition, with both phases lasting approximately 3 s. Before and after the interventions, gait speed (m/s) was assessed using a 10 m walking test, and relative maximal force (Relative Fmax, N/kg) was evaluated during maximal voluntary isometric contraction of PF. From the force–time curve, early (0–50 ms) and late (100–200 ms) rates of force development (RFD) were extracted from the linear slopes (Δ force/Δ time). Results: Gait speed significantly improved in both groups (p < 0.05). However, the improvement was more pronounced in the EXG compared to the STG (p < 0.05). Relative Fmax showed a more significant increase in the STG than in the EXG (p < 0.05). Moreover, a significant 10% increase in early RFD in the STG and a 20.1% increase in the EXG were observed (p < 0.05). The improvement in early RFD was greater in the EXG (p < 0.05). Additionally, late RFD improved significantly only in the EXG (+20.4%, p < 0.05). Conclusion: Explosive resistance training appears particularly effective in improving the ability to rapidly generate force, which is essential for many daily activities requiring explosive movements and quick responses. Full article

(This article belongs to the Special Issue Optimizing Strength and Resistance Training: Best Practices Applied to Sports Disciplines and Performance)

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19 pages, 10479 KiB

Open AccessArticle

Prolactin Inhibition Promotes Follicle Recruitment by Increasing PIKfyve Expression in Ewes During the Estrus Stage

by Sicong Yue, Chunhui Duan, Yong Wang, Xiangyun Li, Ruochen Yang, Yu Li, Xiangyu Chen, Yueqin Liu and Yingjie Zhang

Animals 2024, 14(23), 3541; https://doi.org/10.3390/ani14233541 (registering DOI) - 7 Dec 2024

Abstract

Prolactin (PRL) plays a key role in the growth and ovulation of animal follicles, but its impact on follicular recruitment in ewes remains uncertain. In this study, a total of sixteen healthy ewes (Hu sheep, aged 2–3 years, with continuous reproduction and housed [...] Read more.

Prolactin (PRL) plays a key role in the growth and ovulation of animal follicles, but its impact on follicular recruitment in ewes remains uncertain. In this study, a total of sixteen healthy ewes (Hu sheep, aged 2–3 years, with continuous reproduction and housed separately), matched for parity and weight (52.98 ± 0.96 kg), were randomly assigned to two groups: a control group (C) and a treatment group (T, PRL inhibition). Ovaries were collected in vivo after anesthesia during the estrus stage, and tissue morphology was observed using hematoxylin–eosin (HE) staining. By using RNA sequencing on the ovaries of C and T groups and conducting bioinformatics analysis, the essential genes and pathways involved in the regulation of PRL inhibition were pinpointed. Subcellular localization of key genes in ovarian tissue was determined using a fluorescence in situ hybridization (FISH) assay and immunohistochemistry. The function of key genes was validated using knockout and overexpression techniques. During the estrus phase, we noted a marked rise in the count of large follicles within ovarian tissue following the inhibition of prolactin. In total, 328 differentially expressed genes (DEGs) were detected, with 162 upregulated and 166 downregulated. The results indicated that inhibiting PRL primarily influences follicle recruitment by acting on the target gene PIKfyve. Following the inhibition of PRL during the estrus phase, there was an increase in the expression of PIKfyve. PIKfyve was primarily localized in the ovarian granulosa cells (GCs) and cumulus cells (CCs) in the ovarian tissue of ewes. The overexpression of PIKfyve decreased cell apoptosis and enhanced steroid hormone release, whereas knockout of PIKfyve had the reverse effect. In conclusion, PRL inhibition promoted follicle recruitment in ewes by upregulating PIKfyve during the estrus stage. Full article

(This article belongs to the Section Animal Reproduction)

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19 pages, 720 KiB

Open AccessReview

Biotechnology Revolution Shaping the Future of Diabetes Management

by Nilima Rajpal Kundnani, Bogdan Lolescu, Anca-Raluca Dinu, Delia Mira Berceanu-Vaduva, Patrick Dumitrescu, Tudor-Paul Tamaș, Abhinav Sharma and Mihaela-Diana Popa

Biomolecules 2024, 14(12), 1563; https://doi.org/10.3390/biom14121563 (registering DOI) - 7 Dec 2024

Abstract

Introduction: Diabetes mellitus (DM) has a millennia-long history, with early references dating back to ancient Egypt and India. However, it was not until the 20th century that the connection between diabetes and insulin was fully understood. The sequencing of insulin in the 1950s [...] Read more.

Introduction: Diabetes mellitus (DM) has a millennia-long history, with early references dating back to ancient Egypt and India. However, it was not until the 20th century that the connection between diabetes and insulin was fully understood. The sequencing of insulin in the 1950s initiated the convergence of biotechnology and diabetes management, leading to the development of recombinant human insulin in 1982. This marked the start of peptide-based therapies in DM. Recombinant peptides for DM treatment: Numerous recombinant peptides have been developed since, starting with modified insulin molecules, with the aim of bettering DM management through fine-tuning the glycemic response to insulin. Peptide-based therapies in DM have expanded substantially beyond insulin to include agonists of Glucagon-like peptide-1 receptor and Glucose-dependent insulinotropic polypeptide receptor, glucagon receptor antagonists, and even peptides exerting multiple receptor agonist effects, for better metabolic control. Insulin pumps, continuous glucose monitoring, and automated insulin delivery systems: The development of modern delivery systems combined with real-time glucose monitoring has significantly advanced diabetes care. Insulin pumps evolved from early large devices to modern sensor-augmented pumps with automated shutoff features and hybrid closed-loop systems, requiring minimal user input. The second-generation systems have demonstrated superior outcomes, proving highly effective in diabetes management. Islet cell transplantation, organoids, and biological pancreas augmentation represent innovative approaches to diabetes management. Islet cell transplantation aims to restore insulin production by transplanting donor beta cells, though challenges persist regarding graft survival and the need for immunosuppression. Organoids are a promising platform for generating insulin-producing cells, although far from clinical use. Biological pancreas augmentation relies on therapies that promote beta-cell (re)generation, reduce stress, and induce immune tolerance. Further biotechnology-driven perspectives in DM will include metabolic control via biotechnology-enabled tools such as custom-designed insulin hybrid molecules, machine-learning algorithms to control peptide release, and engineering cells for optimal peptide production and secretion. Full article

(This article belongs to the Section Biological Factors)

22 pages, 7417 KiB

Open AccessArticle

A Novel Approach of −80 °C Cascade Refrigeration System Using Non-Flammable Quaternary Refrigerants for Semiconductor Process Applications

by Su-Been Lee, Chang-Hyo Son and Joon-Hyuk Lee

Energies 2024, 17(23), 6178; https://doi.org/10.3390/en17236178 (registering DOI) - 7 Dec 2024

Abstract

Ultra-low temperature chillers have seen increasing demand with the advancement of semiconductor technology. Mixed refrigerant (MR) cascade refrigeration systems (CRSs) are widely utilized for their stability and high cooling performance at low temperatures. Extensive research has been conducted on optimizing MR, which has [...] Read more.

Ultra-low temperature chillers have seen increasing demand with the advancement of semiconductor technology. Mixed refrigerant (MR) cascade refrigeration systems (CRSs) are widely utilized for their stability and high cooling performance at low temperatures. Extensive research has been conducted on optimizing MR, which has a significant impact on CRS performance. However, most previous studies have either fixed the system pressure or used the refrigeration effect as the sole performance indicator. This did not account for the potential of achieving higher performance with an optimal MR composition at the same target temperature. In this study, a detailed parametric analysis was performed to investigate how the mass fractions of high-, mid-, and low boiling point refrigerants affect the coefficient of performance (COP) and exergy in ultra-low temperature CRSs without fixing the suction pressure. The analysis revealed that at the point of maximum COP, the refrigeration effect was relatively low, highlighting the limitations of using the refrigeration effect alone as a performance indicator. Additionally, COP was found to inversely correlate with total exergy destruction. As cascade temperature increases, COP tends to decrease, emphasizing the need for appropriate cascade temperature selection for MR CRS performance. This study introduces a novel approach to optimizing MR composition under various operating conditions, contributing to the advancement of ultra-low temperature CRSs. Full article

(This article belongs to the Section K: State-of-the-Art Energy Related Technologies)

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