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17 pages, 11551 KiB

Open AccessArticle

Innovative Amber-Based Composite—From Mechanochemical Synthesis and Physicochemical Characterization to Application in Cosmetics

by Małgorzata Wiśniewska, Victoria Paientko, Iwona Ostolska, Karina Tokarska, Natalia Kurinna, Vita Vedmedenko, Olha Konshyna, Volodymyr Gun’ko and Piotr Nowicki

Int. J. Mol. Sci. 2025, 26(9), 4238; https://doi.org/10.3390/ijms26094238 - 29 Apr 2025

Abstract

New ways of ensuring sustainable development in various areas of life are being intensively researched. One of the key priorities is to maximize the use of invaluable natural ingredients in cosmetic products while minimizing the negative impact on the environment. In this study, [...] Read more.

New ways of ensuring sustainable development in various areas of life are being intensively researched. One of the key priorities is to maximize the use of invaluable natural ingredients in cosmetic products while minimizing the negative impact on the environment. In this study, a three-component natural composite based on amber, diatomite, and Phytokeratin^TM (hydrolyzed plant protein) was developed using mechanochemical synthesis. The goal was to maximize the release of biologically active substances, such as succinic acid and Phytokeratin^TM, in aqueous solution. The physicochemical properties of the materials were characterized using Scanning Electron Microscopy (SEM), thermogravimetric (TG) and differential thermogravimetric (DTG) analysis, Fourier Transform Infrared (FTIR) spectroscopy, and Ultraviolet–Visible (UV-Vis) spectrophotometry. Additionally, Density Functional Theory (DFT) was used to perform quantum chemical calculations and characterize molecular interactions in the composite. The optimized composite demonstrated favorable release characteristics and structural properties, confirming its suitability for cosmetic applications. DFT calculations revealed the potential molecular-level interactions between the organic components, indicating the stability and functional integration of the composite. The resulting innovative composite was successfully incorporated into eco-friendly cosmetic formulations, including a solid shampoo bar and a nail conditioner. Full article

(This article belongs to the Special Issue Organic/Inorganic Nanocomposites on the Basis of 'Three Pillars' (Organic Compounds, Metal Nanoparticles, and Carbon Nanomaterials))

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16 pages, 9915 KiB

Open AccessArticle

Role of Oxygen Concentration in Reactive Sputtering of RuO₂ Thin Films: Tuning Surface Chemistry for Enhanced Electrocatalytic Performance

by Swapnil Nalawade, Ebenezer Vondee, Mengxin Liu, Ikenna Chris-Okoro, Sheilah Cherono, Dhananjay Kumar and Shyam Aravamudhan

Crystals 2025, 15(5), 417; https://doi.org/10.3390/cryst15050417 - 29 Apr 2025

Abstract

Developing active electrocatalysts for water splitting is a great challenge due to slow four-electron transfer oxygen evolution reaction. Here, we report the effect of variable oxygen concentrations in sputtered RuO₂ thin films on electrochemical performance. The impact of Ar/O₂ ratios on [...] Read more.

Developing active electrocatalysts for water splitting is a great challenge due to slow four-electron transfer oxygen evolution reaction. Here, we report the effect of variable oxygen concentrations in sputtered RuO₂ thin films on electrochemical performance. The impact of Ar/O₂ ratios on the structural, chemical, and optical properties of sputtered RuO₂ films is systematically investigated. The as-deposited amorphous RuO₂ showed higher catalytic activity as compared to its annealed crystalline counterparts. The X-ray photoelectron spectroscopy results showed controlled stoichiometry with 20% oxygen. The electrochemical measurements of the RuO₂ deposited with a 4:1 Ar:O₂ ratio showed superior performance in cyclic voltammetry, linear sweep voltammetry, and Tafel slope. Transformation of as-deposited amorphous RuO₂ into polycrystalline films is observed at 400 °C of annealing temperature. Film thickness is increased with increasing O₂ concentration during deposition. This study highlights that sputtered RuO₂ thin films with varying oxygen concentration during deposition can influence the electrocatalytic activities in water-splitting applications. Full article

(This article belongs to the Special Issue Advanced Materials for Applications in Water Splitting)

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19 pages, 2205 KiB

Open AccessArticle

The Genetic Elements of the Obesity Paradox in Atherosclerosis Identified in an Intercross Between Hyperlipidemic Mouse Strains

by Mei-Hua Chen, Bilhan Chagari, Ashley M. Abramson, Lisa J. Shi, Jiang He and Weibin Shi

Int. J. Mol. Sci. 2025, 26(9), 4241; https://doi.org/10.3390/ijms26094241 - 29 Apr 2025

Abstract

Overweight and obese individuals show lower mortality rates or better prognoses than those of normal weight in a variety of diseases, a phenomenon called the “obesity paradox”. An inverse association of adiposity with atherosclerosis has been observed in both humans and mice. To [...] Read more.

Overweight and obese individuals show lower mortality rates or better prognoses than those of normal weight in a variety of diseases, a phenomenon called the “obesity paradox”. An inverse association of adiposity with atherosclerosis has been observed in both humans and mice. To dissect phenotypic and genetic connections between the traits, 154 female and 145 male F2 mice were generated from an intercross between BALB/cJ and LP/J apolipoprotein E-deficient mice and fed a Western diet for 12 weeks. Atherosclerotic lesion size in the aortic root, body weight, plasma lipids, and glucose were measured, and genotyping was performed on miniMUGA SNP arrays. Quantitative trait locus (QTL) analyses on all F2 mice with sex as a covariate revealed four significant QTLs on chromosomes (Chr) 3, 6, 13, and 15 for atherosclerosis and three significant QTLs on Chr2, 7, and 15 for body weight. Chr15 QTL for atherosclerosis overlapped with one for body weight near 36 Mb. After adjusting for variation in body weight, Chr15 atherosclerosis QTL was downgraded from significant to suggestive linkage. Body weight was inversely correlated with atherosclerotic lesion sizes and accounted for more variance than a single other risk factor for atherosclerosis among F2 mice. Analysis of public data collected from two backcross cohorts revealed strong correlations between body weight and fat mass in adult mice (r ≥ 0.93; p ≤ 1.6 × 10⁻¹³⁶). Thus, the obesity paradox in atherosclerosis is partially attributable to shared genetic components that have an opposite effect on adiposity and atherosclerosis. Full article

(This article belongs to the Special Issue Molecular Mechanisms Linking Obesity to Atherosclerosis Pathogenesis)

14 pages, 4511 KiB

Open AccessArticle

The Metabolic Consequences of Pathogenic Variant in FXYD2 Gene Encoding the Gamma Subunit of Sodium/Potassium-Transporting ATPase in Two Siblings with Sodium-Dependent Defect of Fructose, Galactose and Glucose Renal Reabsorption

by Jan Zawadzki, Ryszard Grenda, Agnieszka Madej-Pilarczyk and Elżbieta Ciara

Genes 2025, 16(5), 535; https://doi.org/10.3390/genes16050535 (registering DOI) - 29 Apr 2025

Abstract

Background: Abnormal sodium-dependent hexose reabsorption in the proximal tubule, accompanied by a functional decrease in sodium and water reabsorption under conditions of increased volemia, may be attributed to a dysfunction of primary transporters related to a genetic defect in the Na,K-ATPase gamma subunit. [...] Read more.

Background: Abnormal sodium-dependent hexose reabsorption in the proximal tubule, accompanied by a functional decrease in sodium and water reabsorption under conditions of increased volemia, may be attributed to a dysfunction of primary transporters related to a genetic defect in the Na,K-ATPase gamma subunit. Methods: We examined two sisters, aged 6 and 8 years, who presented with hypercalciuria, glucosuria, fructosuria, galactosuria, and atypical proteinuria. Primary diabetes, galactosemia, and fructosemia were excluded, suggesting a defect in cellular hexose transport in the proximal tubule. We conducted tests on the family members to assess the impact of gradually increasing volemia, using a water-loading test, on tubular H+ transport and urinary excretion of calcium, citrate, endothelin-1 (ET-1), and atypical proteins. Whole-exome sequencing was performed in the affected patients to identify the genetic basis of this phenotype. Results: Extended investigations revealed a complex defect in tubular H⁺ transport, calcium and citrate handling, and atypical proteinuria, resulting from water load-driven overproduction of endothelin-1 (ET-1). Genetic analysis identified a heterozygous pathogenic variant, c.80G>A, p.(Arg27His), in the FXYD2 gene, which encodes the gamma subunit of sodium/potassium-transporting ATPase. Conclusions: Our findings provide evidence that a defect in FXYD2 (splice form a) leads to functional impairment of proximal tubular hexose reabsorption. This is the first report on the metabolic consequences of a pathogenic FXYD2 variant affecting the gamma subunit of sodium/potassium-transporting ATPase in humans. The genotype–phenotype correlation in two siblings with a sodium-dependent defect in fructose, galactose, and glucose renal reabsorption allowed us to characterize a disease with a distinct clinical course and biochemical profile, not previously reported in the medical literature or genetic databases. Analysis of this condition was crucial for the early introduction of reno-protective treatment aimed at slowing the progression of nephropathy and for risk assessment in family members, which was essential for genetic counseling. Full article

(This article belongs to the Section Human Genomics and Genetic Diseases)

21 pages, 2703 KiB

Open AccessArticle

Efficiency and Energy Consumption of Partial Carbonation Process for CO₂ Capture from Natural Gas Combustion

by Rubens Coutinho Toledo, Caio Leandro de Moraes, Vinoth Thangarasu, João Andrade de Carvalho, Jr. and Ivonete Avila

Energies 2025, 18(9), 2285; https://doi.org/10.3390/en18092285 (registering DOI) - 29 Apr 2025

Abstract

Brazil has set a goal to reduce greenhouse gas (GHG) emissions, which is a significant opportunity to leverage calcium looping (CaL) technology for energy generation in natural gas power plants. CaL is a promising technology, due to sorbent low cost and availability, but [...] Read more.

Brazil has set a goal to reduce greenhouse gas (GHG) emissions, which is a significant opportunity to leverage calcium looping (CaL) technology for energy generation in natural gas power plants. CaL is a promising technology, due to sorbent low cost and availability, but its industrial implementation performance decay is a major challenge to face. While evaluating carbon-capture technologies, net emissions perspective is essential, and optimizing CaL capture through a partial carbonation cycle is a promising approach, both to reduce net emissions and improve the number of cycles before deactivation. In this context, a Brazilian dolomite was characterized and evaluated, to be used as sorbent in a CaL process employed in natural gas power plants. For such a purpose, a novel methodology has been proposed to evaluate the mass ratio of CO₂ captured, to assess the energy consumed in the process. A rotatable central composite design (RCCD) model was used to identify the optimal temperature and residence time conditions in the carbonation stage of the CaL process, focusing on achieving energy efficiency. The five most promising conditions were then tested across 10 calcination–carbonation cycles, to examine the impact of partial carbonation in capture efficiency over extended cycles. The results indicate that temperature plays a critical role in the process, particularly in terms of capture efficiency, while residence time significantly affects energy consumption. The conditions that demonstrated optimal performance for both the single and the multi-cycle tests were 580 °C for 7.5 min and 550 °C for 10 min, given that index of capture efficiency (

{IEC}_{10, c}

) values of 1.34 and 1.20 were found, respectively—up to 40% higher than at 475 °C. There was lower energy expenditure at 580 °C (

E_{s p}

) (33.48 kJ), 550 °C (

E_{s p}

= 37.97 kJ),

{CO}_{2}

mass captured (

{CO}_{2} c a p

= 9.80 mg), and the samples exhibited a more preserved surface, thus making it the most suitable option for scale-up applications. Full article

(This article belongs to the Section B3: Carbon Emission and Utilization)

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17 pages, 5373 KiB

Open AccessArticle

Rotating Photo-Disc Reactor (RPR) Used in the Photo-Degradation of Pyridine Using Zinc Oxide as a Catalyst Composited with Aluminum Nanoparticles and Irradiated with Natural Light

by Carlos Montalvo, Edith Lemus, Claudia A. Aguilar, Rosa M. Cerón, Julia G. Cerón, Juan C. Robles and Alejandro Ruiz

Catalysts 2025, 15(5), 437; https://doi.org/10.3390/catal15050437 - 29 Apr 2025

Abstract

Pyridine was degraded in a rotating photo-disc reactor (RPR) using zinc oxide (ZnO) doped with aluminum nanoparticles (ZnO-Al) as a catalyst and natural light lamps. The reactor disks made of clay had a surface area of 329.7209 m². The reactor was [...] Read more.

Pyridine was degraded in a rotating photo-disc reactor (RPR) using zinc oxide (ZnO) doped with aluminum nanoparticles (ZnO-Al) as a catalyst and natural light lamps. The reactor disks made of clay had a surface area of 329.7209 m². The reactor was operated as a semi-batch system, where it handled a volume of 14.8 L and had a hydraulic residence time (HRT) of 72 h at 54 rpm with a constant flow rate. The results indicate an average degradation of 50.6% after an HRT of 72 h, with a maximum degradation of 62%. The characterization results confirm the effectiveness of the doping process, showing an aluminum concentration of 4.11% by mass in the catalyst, as determined by X-ray techniques. Overall, the doping process proved effective for the zinc oxide catalyst, as evidenced by a reduction in the catalyst bandgap from 3.25 eV for undoped ZnO to 3.08 eV for the doped version, making it sufficiently active under artificial visible light. Full article

(This article belongs to the Special Issue Environmental Catalysis in Advanced Oxidation Processes, 2nd Edition)

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28 pages, 6488 KiB

Open AccessArticle

Decrypting the Unusual Structure and σ-Hole Interactions of the XC(NO₂)₃ (X=F, Cl, Br, and I) Compounds Using Quasi-Atomic Orbitals

by Emilie B. Guidez

Molecules 2025, 30(9), 1986; https://doi.org/10.3390/molecules30091986 (registering DOI) - 29 Apr 2025

Abstract

This work reports the quasi-atomic orbital analysis of the XC(NO₂)₃ (X=F, Cl, Br, and I) compounds and shows that the interactions between the C-N σ bonds and the lone electron pairs on the halogen atom and oxygen atoms of the [...] Read more.

This work reports the quasi-atomic orbital analysis of the XC(NO₂)₃ (X=F, Cl, Br, and I) compounds and shows that the interactions between the C-N σ bonds and the lone electron pairs on the halogen atom and oxygen atoms of the nitro groups may contribute to the unusually short C-X distances observed. While the presence of a σ-hole on the halogen atom of the XC(NO₂)₃ compound may not be obvious from the electron density distribution, an analysis of the intermolecular forces of the NH₃--XC(NO₂)₃ complexes suggests a σ -hole interaction between the nitrogen lone pair and halogen atom X (X=Cl, Br, and I) in the linear N--X-C configuration, where electrostatics and exchange forces dominate. The linear N--X-C bond in these systems is shown to have a noticeable covalent character, which is captured in the polarization energy term. Complexation with the ammonia nucleophile is shown to affect the electronic structure of the entire compounds, notably the oxygen/halogen lone electron pairs interactions with the C-N σ bonds. Full article

(This article belongs to the Special Issue Fundamental Aspects of Chemical Bonding—2nd Edition)

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32 pages, 5315 KiB

Open AccessArticle

Correlating Indoor Environmental Quality Parameters with Human Physiological Responses for Adaptive Comfort Control in Commercial Buildings

by Haoyue Dai, Saba Imani and Joon-Ho Choi

Energies 2025, 18(9), 2280; https://doi.org/10.3390/en18092280 (registering DOI) - 29 Apr 2025

Abstract

This study investigates the critical role of indoor environmental quality (IEQ) adaptations in influencing human physiological responses within commercial building settings. By integrating environmental engineering and human physiology, this research offers empirical insights into the relationship between IEQ modifications and occupant well-being, particularly [...] Read more.

This study investigates the critical role of indoor environmental quality (IEQ) adaptations in influencing human physiological responses within commercial building settings. By integrating environmental engineering and human physiology, this research offers empirical insights into the relationship between IEQ modifications and occupant well-being, particularly in the context of energy performance and efficiency. This study examines correlations between human physiological responses and key IEQ components, including indoor air quality (IAQ), thermal comfort, lighting, and acoustics, using data collected from two office areas with 14 participants. Sensors tracked environmental parameters, while wearable devices monitored physiological responses. Cross-correlation analysis revealed significant relationships between physiological indicators and environmental factors, with indoor temperature, PM_2.5, and relative humidity showing the strongest impacts on electrodermal activity, skin temperature, and stress levels, respectively (p < 0.05). Furthermore, supervised machine learning techniques were employed to develop predictive models that evaluate IAQ and thermal comfort at both personal and general levels. Individual models achieved 84.76% accuracy for IAQ evaluation and 70.5% for thermal comfort prediction, outperforming the general model (69.7% and 64.3%, respectively). Males showed greater overall sensitivity to IEQ indicators, while females demonstrated higher sensitivity specifically to air quality and thermal comfort conditions. The findings underscore the potential of physiological signals to predict environmental satisfaction, providing a foundation for designing energy-efficient buildings that prioritize occupant health and comfort. This research bridges a critical gap in the literature by offering data-driven approaches to align sustainable building practices with human-centric needs. Future studies should expand participant diversity and explore broader demographics to enhance the robustness and applicability of predictive models. Full article

(This article belongs to the Special Issue Human-Centered Energy Optimization in Built Environment)

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18 pages, 3041 KiB

Open AccessArticle

Atomistic Mechanism of Ion Solution Evaporation: Insights from Molecular Dynamics

by Dayuan Yuan, Liuyang Zhang, Chao Li and Shengqiang Shen

Processes 2025, 13(5), 1369; https://doi.org/10.3390/pr13051369 (registering DOI) - 29 Apr 2025

Abstract

The study of ion solution evaporation is of paramount importance to the environment as it pertains to numerous critical domains in our lives. This research employs molecular dynamics methods to systematically investigate the influence of ion species, concentration, temperature, and the surface area-to-volume [...] Read more.

The study of ion solution evaporation is of paramount importance to the environment as it pertains to numerous critical domains in our lives. This research employs molecular dynamics methods to systematically investigate the influence of ion species, concentration, temperature, and the surface area-to-volume ratio on the ion solution evaporation process. Firstly, we introduce the process of molecular dynamics modeling of ion solutions, encompassing the selection of simulation parameters, the definition of potential energy functions, and the adjustment of time steps. Subsequently, we analyze the molecular dynamics simulation results from various aspects, such as atomic motion and ion concentration distribution, to elucidate the mechanisms underlying the ion solution evaporation. Finally, we summarize the significance of this study, emphasizing its potential applications in industrial production, water resource management, and ecological preservation, thereby providing a robust theoretical foundation for environmental protection and sustainable development. Full article

(This article belongs to the Section Chemical Processes and Systems)

14 pages, 3629 KiB

Open AccessArticle

Identification and Functional Exploration of the ALKBH Gene Family in Oriental Melon Fruit Ripening

by Chong Zhang, Xinqi Guo, Ying Zhang, Hongbo Pang and Qiang Chen

Int. J. Mol. Sci. 2025, 26(9), 4254; https://doi.org/10.3390/ijms26094254 (registering DOI) - 29 Apr 2025

Abstract

N6-methyladenosine (m⁶A) methylation functions as a vital post-transcriptional and epigenetic modification in higher plants regulated by α-ketoglutarate-dependent dioxygenases (ALKBH). However, the role of ALKBH genes in oriental melon (Cucumis melo L.) fruit ripening has not been explored. Therefore, we treated [...] Read more.

N6-methyladenosine (m⁶A) methylation functions as a vital post-transcriptional and epigenetic modification in higher plants regulated by α-ketoglutarate-dependent dioxygenases (ALKBH). However, the role of ALKBH genes in oriental melon (Cucumis melo L.) fruit ripening has not been explored. Therefore, we treated oriental melon with an exogenous m⁶A demethylase inhibitor (mechlorfenamic acid) then analyzed endogenous ethylene production and ripening-related indicators to explore the effects of m⁶A methylation on ripening. Bioinformatics and real-time quantitative PCR analyses were used to determine the impact of ALKBH genes on key ethylene synthesis gene expression. Treatment effectively inhibited endogenous ethylene production, firmness changes, and soluble solid contents, thereby extending fruit ripening. Eight ALKBH gene family members belonging to five major groups were identified in the melon genome. All members were expressed in ripening fruits, with different expression patterns during ripening. CmALKBH6, CmALKBH7, and CmALKBH8 expression was inhibited by an ethylene inhibitor (1-methylcyclopropene). The transient overexpression (OE) of CmALKBH8 in oriental melon led to the increased expression of the ethylene synthesis genes CmACS1, CmACS2, and CmACO1. In summary, the ethylene-regulated gene CmALKBH8 may participate in oriental melon fruit ripening regulation by modulating the methylation levels of ethylene synthesis-related genes. These findings help us better understand how m⁶A methylation regulates melon ripening. Full article

(This article belongs to the Section Molecular Plant Sciences)

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19 pages, 1571 KiB

Open AccessArticle

Impacts of Various Reheating Methods on Crispy Chicken: Physicochemical Properties, Oxidation and Flavor Profiles

by Xiaona Ren, Chun Wang, Xueqing Wang, Tingting Su and Yigang Yu

Foods 2025, 14(9), 1574; https://doi.org/10.3390/foods14091574 (registering DOI) - 29 Apr 2025

Abstract

In this study, the impacts of water-bath reheating (WR), steam reheating (SR), air-frying reheating (AR), roasting reheating (RR), and microwave reheating (MR) on the physicochemical properties, oxidation, and flavor profiles of crispy chicken (CC) were investigated. The results revealed that the pH of [...] Read more.

In this study, the impacts of water-bath reheating (WR), steam reheating (SR), air-frying reheating (AR), roasting reheating (RR), and microwave reheating (MR) on the physicochemical properties, oxidation, and flavor profiles of crispy chicken (CC) were investigated. The results revealed that the pH of CC was significantly reduced after reheating (p < 0.05). The AR samples had a slight change in L* and the highest springiness. The RR samples had the highest degree of lipid and protein oxidation. In addition, WR, AR, RR, and MR treatments effectively increased the contents of umami-related amino acids. Glu and Cys were typically the taste-active amino acids in CC. AR contributed to increasing the response values of umami and richness. As shown by the electronic nose and Gas Chromatography–Mass Spectrometry (GC-MS) analysis, 41 volatile compounds were obtained in CC. AR could efficiently increase the contents of nitrogen oxides and methyl compounds. Meanwhile, the content of trans-.alpha.-bergamotene, nonanal, and copaene were significantly increased after the AR process (p < 0.05). According to the results of analysis of variance (ANOVA), odor activity value (OAV), and variable importance in projection (VIP), anethole was considered the key differential flavor-active compound. Overall, AR was superior to other reheating methods in CC, with better texture and various flavor characteristics. This study provides a reference for choosing reheating technology for pre-cooked chicken products. Full article

(This article belongs to the Section Meat)

24 pages, 4775 KiB

Open AccessArticle

Analysis of the Pelletability of Vegetable Crop Foliage Using a Commercial Flat Die Pellet Mill

by Omid Gholami Banadkoki, Shahab Sokhansanj and Anthony Lau

Energies 2025, 18(9), 2284; https://doi.org/10.3390/en18092284 (registering DOI) - 29 Apr 2025

Abstract

Agricultural residues serve as a vast yet underutilized biomass resource with significant potential for bioenergy and biomaterial applications. Converting these residues into densified biomass pellets enhances energy density, handling efficiency, and transportability, offering a sustainable alternative to conventional feedstocks. While extensive research has [...] Read more.

Agricultural residues serve as a vast yet underutilized biomass resource with significant potential for bioenergy and biomaterial applications. Converting these residues into densified biomass pellets enhances energy density, handling efficiency, and transportability, offering a sustainable alternative to conventional feedstocks. While extensive research has focused on woody biomass, studies on the pelletization of vegetable crop foliage remain limited. This study examines the pelletability of foliage from corn, soybean, tomato, eggplant, cucumber, and summer squash, assessing their physical properties, bulk durability, bulk density, and energy consumption during pelletization. Results demonstrated that variation in biomass composition significantly influences pellet quality, with lignin content improving durability and ash content affecting moisture uptake and combustion properties. Cucumber had the highest pellet density (691.2 kg/m³) and durability (97.9%), making it suitable for long-term storage and transport. Sawdust exhibited the lowest moisture absorption (16–18% db), which is attributed to its highest lignin content. Pelletization energy requirements varied significantly, with cucumber (21.8 kWh/t) and summer squash (18.7 kWh/t) requiring the lowest energy input, whereas soybean (49.6 kWh/t) and sawdust (47.3 kWh/t) exhibited the highest energy demands due to greater resistance to densification. A predictive model was developed to correlate single pellet density and durability with bulk pellet properties—yielding high predictive accuracy, with R² = 0.936 for bulk density (𝐵𝐷ₑ) and R² = 0.861 for bulk durability (𝐵𝐷ᵤ)—thereby facilitating process optimization for large-scale pellet production. This study demonstrated that foliage residues from greenhouse crops, such as cucumber and summer squash, can be effectively pelletized with low energy input and high physical integrity. These outcomes suggest that such underutilized agricultural residues hold promise as a densified intermediate feedstock, supporting future applications in bioenergy systems and advancing circular resource use in controlled-environment agriculture. Full article

(This article belongs to the Special Issue Biomass and Bio-Energy—2nd Edition)

24 pages, 1696 KiB

Open AccessArticle

Protocell Dynamics: Modelling Growth and Division of Lipid Vesicles Driven by an Autocatalytic Reaction

by Japraj Taneja and Paul G. Higgs

Life 2025, 15(5), 724; https://doi.org/10.3390/life15050724 (registering DOI) - 29 Apr 2025

Abstract

We study a computational model of a protocell, in which an autocatalytic reaction sustains itself inside a lipid vesicle. The autocatalytic reaction drives volume growth via osmosis. Membrane area grows due to addition of lipids from the environment. The membrane growth rate depends [...] Read more.

We study a computational model of a protocell, in which an autocatalytic reaction sustains itself inside a lipid vesicle. The autocatalytic reaction drives volume growth via osmosis. Membrane area grows due to addition of lipids from the environment. The membrane growth rate depends on the external lipid concentration and on the tension in the membrane. In the absence of division, a cell either reaches a state of homeostasis or grows to a point where the internal reaction collapses. If a cell becomes elongated, it can divide into two smaller spherical vesicles, conserving the total volume and area. We determine when it is energetically favorable for a large vesicle to divide. Division requires the buildup of a difference between the lipid areas on the outer and inner leaflets of the membrane. Division occurs most easily when the rate of flipping of lipids between leaflets is relatively slow. If the flipping is too fast, the parent cell grows large without dividing. There is a typical size at which division occurs, producing two daughter cells of unequal sizes. The smaller and larger daughters regrow to the same typical size before the next division. Protocells with an active metabolism reach a stable state where the internal autocatalytic reaction and the membrane growth are well balanced. Active protocells can grow and divide in conditions where an inactive vesicle without an internal reaction cannot. Full article

(This article belongs to the Special Issue 2nd Edition—Featured Papers on the Origins of Life)

14 pages, 3112 KiB

Open AccessArticle

Optical–Electronic Skin Based on Tea Polyphenol for Dual Signal Wearable Sensing

by Jia-Li Xu, Guangyao Zhao, Jiachen Wang, An Tang, Jun-Tao Liu, Zhijie Zhu, Qiang Zhang and Yu Tian

Biosensors 2025, 15(5), 281; https://doi.org/10.3390/bios15050281 (registering DOI) - 29 Apr 2025

Abstract

The rapid development of smart electronic skin has led researchers to design a variety of flexible and stretchable devices that can be used to monitor physiological and environmental signals. In this work, we successfully demonstrate a color-adjustable and conductive wearable optical–electronic skin (OE-skin) [...] Read more.

The rapid development of smart electronic skin has led researchers to design a variety of flexible and stretchable devices that can be used to monitor physiological and environmental signals. In this work, we successfully demonstrate a color-adjustable and conductive wearable optical–electronic skin (OE-skin) based on photonic crystal hydrogel that is capable of delivering both optical and electrical signal responses synchronously. The OE-skin is fabricated by incorporating a structural colored layer, composed of periodically aligned magnetic nanoparticles, into a polyacrylamide hydrogel matrix that contains tea polyphenols and borax. The dynamic boronate ester bonds formed between borax and the catechol groups of tea polyphenols are able to enhance the mechanical properties of the OE-skin, while also conferring excellent electrical conductivity, high sensitivity, and a rapid electrical response. Additionally, the tea polyphenols, which are natural active compounds derived from tea, possess diverse bioactive properties, thereby endowing the OE-skin with excellent antibacterial and biocompatibility characteristics. In addition, the developed electronic skin successfully demonstrates its capability in synergistic electronic and optical sensing during human motion monitoring, indicating broad application prospects in the field of smart wearable sensors. Full article

(This article belongs to the Special Issue Advanced Bioelectronics for Healthcare Monitoring and Disease Diagnosis)

22 pages, 925 KiB

Open AccessArticle

Improvement of the Structure and Antioxidant Activity of Protein–Polyphenol Complexes in Barley Malts Using Roasting Methods

by Guozhi Wu, Huiting Lin and Yongsheng Chen

Antioxidants 2025, 14(5), 538; https://doi.org/10.3390/antiox14050538 (registering DOI) - 29 Apr 2025

Abstract

Proteins and polyphenols are important components in barley malt. During the roasting process of barley malt, proteins and polyphenols interact and influence each other, ultimately altering the nutritional profile and functional properties of barley malt. In this research, polyphenol-free proteins and protein–polyphenol complexes [...] Read more.

Proteins and polyphenols are important components in barley malt. During the roasting process of barley malt, proteins and polyphenols interact and influence each other, ultimately altering the nutritional profile and functional properties of barley malt. In this research, polyphenol-free proteins and protein–polyphenol complexes were extracted from barley malt subjected to varying degrees of roasting. The antioxidant activity of protein–polyphenol complexes was assessed by ABTS, FRAP, and ORAC assays. The structural characteristics of the proteins were examined through UV, FL, CD, FTIR, and SEM. We found that roasting enhances the solubility of globulin, prolamin, and glutenin and facilitates the binding of these proteins with polyphenols. Conversely, the impact of roasting on albumin exhibits a trend opposite to that observed in the other three proteins. The antioxidant activity of protein–polyphenol complexes was significantly higher than that of polyphenol-free proteins. Additionally, the microenvironment of the amino acid residues of the four proteins exhibited increased polarity following the roasting process, and the structural conformation of albumin, globulin, and glutelin transitioned from an ordered to a disordered state. Our results indicate that roasting enhances the antioxidant activity of protein–polyphenol complexes by altering the secondary and tertiary structures of these proteins, thereby exposing more hydrophobic side-chain groups inside the proteins and offering more binding sites for polyphenols. Full article

17 pages, 1702 KiB

Open AccessArticle

Inorganic Arsenic Induces Elevated p53 Levels with Altered Functionality Impacting the Expression of Toll-like Receptor 3 and Other Target Genes in Immortalized Prostate Epithelial Cells

by Nancy C. Pacheco-Castillo, Jesús Gómez-Montalvo, Vanesa Olivares-Illana, Félix Recillas-Targa, Erik J. Tokar, S. Eréndira Avendaño-Vázquez and Claudia Escudero-Lourdes

Int. J. Mol. Sci. 2025, 26(9), 4253; https://doi.org/10.3390/ijms26094253 (registering DOI) - 29 Apr 2025

Abstract

Prostate cancer (PCa) is a major global health concern, particularly in advanced stages where chemotherapy resistance and androgen-independent tumor growth reduce survival rates to below 30%. Toll-like receptor 3 (TLR3), regulated by tumor suppressor p53, is a promising therapeutic target due to its [...] Read more.

Prostate cancer (PCa) is a major global health concern, particularly in advanced stages where chemotherapy resistance and androgen-independent tumor growth reduce survival rates to below 30%. Toll-like receptor 3 (TLR3), regulated by tumor suppressor p53, is a promising therapeutic target due to its role in tumor cell apoptosis. However, chronic exposure to inorganic arsenic (iAs), a known carcinogen, has been linked to PCa progression and reduced TLR3 expression and activation by polyinosinic/polycytidylic acid (Poly(I/C)), a synthetic ligand used in PCa immunotherapy. Here, we demonstrate that chronic sodium arsenite (NaAsO) exposure increases p53 transcript and protein levels in immortalized prostate epithelial cells. Despite this, key p53 target genes, including TLR3, CDKN1A, and BAX, were significantly downregulated, indicating a transcriptionally inactive p53. Chromatin immunoprecipitation (ChIP) confirmed diminished p53 binding to TLR3 and CDKN1A promoters, while sequencing ruled out TP53 mutations. A bioinformatic analysis revealed elevated TP53 but reduced TLR3 and CDKN1A in prostate adenocarcinoma, suggesting that iAs-induced oxidative stress disrupts p53 function. These findings reveal a novel mechanism by which iAs promotes PCa progression through impaired p53 activity, highlighting the need to explore post-translational and epigenetic factors affecting p53. Restoring p53 transcriptional activity may offer a therapeutic strategy for PCa patients exposed to NaAsO. Full article

(This article belongs to the Section Molecular Biology)

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20 pages, 3991 KiB

Open AccessArticle

Multi-Objective Optimization for the Low-Carbon Operation of Integrated Energy Systems Based on an Improved Genetic Algorithm

by Yao Duan, Chong Gao, Zhiheng Xu, Songyan Ren and Donghong Wu

Energies 2025, 18(9), 2283; https://doi.org/10.3390/en18092283 (registering DOI) - 29 Apr 2025

Abstract

As global climate change and energy crises intensify, the pursuit of low-carbon integrated energy systems (IESs) has become increasingly important. This paper proposes an improved genetic algorithm (IGA) designed to optimize the multi-objective low-carbon operations of IESs, aiming to minimize both operating costs [...] Read more.

As global climate change and energy crises intensify, the pursuit of low-carbon integrated energy systems (IESs) has become increasingly important. This paper proposes an improved genetic algorithm (IGA) designed to optimize the multi-objective low-carbon operations of IESs, aiming to minimize both operating costs and carbon emissions. The IGA incorporates circular crossover and polynomial mutation techniques, which not only preserve advantageous traits from the parent population but also enhance genetic diversity, enabling comprehensive exploration of potential solutions. Additionally, the algorithm selects parent populations based on individual fitness and dominance, retaining successful chromosomes and eliminating those that violate constraints. This process ensures that subsequent generations inherit superior genetic traits while minimizing constraint violations, thereby enhancing the feasibility of the solutions. To evaluate the effectiveness of the proposed algorithm, we tested it on three different IES scenarios. The results demonstrate that the IGA successfully reduces equality constraint violations to below 0.3 kW, representing less than 0.2% deviation from the IES’s power demand in each time slot. We compared its performance against a multi-objective genetic algorithm, a multi-objective particle swarm algorithm, and a single-objective genetic algorithm. Compared to conventional genetic algorithms, the IGA achieved maximum 5% improvement in both operational cost reduction and carbon emission minimization objectives compared to the unimproved single-objective genetic algorithm, demonstrating its superior performance in multi-objective optimization for low-carbon IESs. These outcomes underscore the algorithm’s reliability and practical applicability. Full article

(This article belongs to the Special Issue Advances in Simulations and Analysis of Electrical Power Systems: Enhancing Efficiency, Reliability and Sustainability)

31 pages, 5696 KiB

Open AccessArticle

Sustainable Biogenic Synthesis of High-Performance CaO/NiO Nanocomposite for Antimicrobial, Antioxidant, and Antidiabetic Applications

by Saravanan Priyadharshini, Muniappan Ayyanar, Ravichandran Krishnasamy, Manimaran Sundarraj, Gabriela Sandoval Sandoval-Hevia, Arun Thirumurugan and Natarajan Chidhambaram

Ceramics 2025, 8(2), 46; https://doi.org/10.3390/ceramics8020046 (registering DOI) - 29 Apr 2025

Abstract

Herein, we present in-depth investigations of the biological activities of a CaO/NiO nanocomposite synthesized via a sustainable eco-friendly approach, utilizing Citrus limonium fruit extract as a natural stabilizing and facilitating agent. The efficacy of the nanocomposite is compared with those of individual CaO [...] Read more.

Herein, we present in-depth investigations of the biological activities of a CaO/NiO nanocomposite synthesized via a sustainable eco-friendly approach, utilizing Citrus limonium fruit extract as a natural stabilizing and facilitating agent. The efficacy of the nanocomposite is compared with those of individual CaO and NiO nanoparticles. X-ray diffraction analysis confirms the cubic phase of CaO as well as NiO within a unified matrix, demonstrating a refined crystallite size of 48 nm, which is smaller than that of the individual nanoparticles. FTIR study substantiates the occurrence of strong Ca-O-Ni-O bonds, along with CO₃²⁻, C–H, and CH₂ bonds. The CaO, NiO, and CaO/NiO samples exhibit bandgap values of 1.70, 3.46, and 3.44 eV, respectively. Surface morphology analysis reveals that CaO/NiO holds a well-defined heterostructure with porous morphology. An XPS study confirms that Ca and Ni elements exist in the 2+ oxidation state in the CaO/NiO. The nanocomposite exhibits superior antibacterial activity, with inhibition zones of 24.3 mm against Bacillus subtilis and 20.6 mm against Salmonella typhi, and MIC values of 23.4 and 46.8 µg/mL, respectively. It also demonstrates strong antioxidant potential, with IC₅₀ values of 96.8 ± 0.4 µg/mL (DPPH) and 91.8 ± 0.1 µg/mL (superoxide anion). Furthermore, it shows the lowest IC₅₀ for α-amylase (98.6 ± 0.7 µg/mL) and strong α-glucosidase inhibition (81.96 ± 0.5 µg/mL). Consequently, this insightful study reveals how biogenic synthesis helps develop high-performance multifunctional CaO/NiO nanocomposites for biomedical applications. Full article

(This article belongs to the Special Issue Ceramics Containing Active Molecules for Biomedical Applications)

19 pages, 3604 KiB

Open AccessReview

Susceptibility-Weighted Imaging (SWI): Technical Aspects and Applications in Brain MRI for Neurodegenerative Disorders

by Federica Vaccarino, Carlo Cosimo Quattrocchi and Marco Parillo

Bioengineering 2025, 12(5), 473; https://doi.org/10.3390/bioengineering12050473 (registering DOI) - 29 Apr 2025

Abstract

Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) sequence sensitive to substances that alter the local magnetic field, such as calcium and iron, allowing phase information to distinguish between them. SWI is a 3D gradient–echo sequence with high spatial resolution that leverages [...] Read more.

Susceptibility-weighted imaging (SWI) is a magnetic resonance imaging (MRI) sequence sensitive to substances that alter the local magnetic field, such as calcium and iron, allowing phase information to distinguish between them. SWI is a 3D gradient–echo sequence with high spatial resolution that leverages both phase and magnitude effects. The interaction of paramagnetic (such as hemosiderin and deoxyhemoglobin), diamagnetic (including calcifications and minerals), and ferromagnetic substances with the local magnetic field distorts it, leading to signal changes. Neurodegenerative diseases are typically characterized by the progressive loss of neurons and their supporting cells within the neurovascular unit. This cellular decline is associated with a corresponding deterioration of both cognitive and motor abilities. Many neurodegenerative disorders are associated with increased iron accumulation or microhemorrhages in various brain regions, making SWI a valuable diagnostic tool in clinical practice. Suggestive SWI findings are known in Parkinson’s disease, Lewy body dementia, atypical parkinsonian syndromes, multiple sclerosis, cerebral amyloid angiopathy, amyotrophic lateral sclerosis, hereditary ataxias, Huntington’s disease, neurodegeneration with brain iron accumulation, and chronic traumatic encephalopathy. This review will assist radiologists in understanding the technical framework of SWI sequences for a correct interpretation of currently established MRI findings and for its potential future clinical applications. Full article

(This article belongs to the Special Issue Modern Medical Imaging in Disease Diagnosis Applications)

136 pages, 13550 KiB

Open AccessPerspective

Alzheimer’s Is a Multiform Disease of Sustained Neuronal Integrated Stress Response Driven by the C99 Fragment Generated Independently of AβPP; Proteolytic Production of Aβ Is Suppressed in AD-Affected Neurons: Evolution of a Theory

by Vladimir Volloch and Sophia Rits-Volloch

Int. J. Mol. Sci. 2025, 26(9), 4252; https://doi.org/10.3390/ijms26094252 (registering DOI) - 29 Apr 2025

Abstract

The present Perspective analyzes the remarkable evolution of the Amyloid Cascade Hypothesis 2.0 (ACH2.0) theory of Alzheimer’s disease (AD) since its inception a few years ago, as reflected in the diminishing role of amyloid-beta (Aβ) in the disease. In the initial iteration of [...] Read more.

The present Perspective analyzes the remarkable evolution of the Amyloid Cascade Hypothesis 2.0 (ACH2.0) theory of Alzheimer’s disease (AD) since its inception a few years ago, as reflected in the diminishing role of amyloid-beta (Aβ) in the disease. In the initial iteration of the ACH2.0, Aβ-protein-precursor (AβPP)-derived intraneuronal Aβ (iAβ), accumulated to neuronal integrated stress response (ISR)-eliciting levels, triggers AD. The neuronal ISR, in turn, activates the AβPP-independent production of its C99 fragment that is processed into iAβ, which drives the disease. The second iteration of the ACH2.0 stemmed from the realization that AD is, in fact, a disease of the sustained neuronal ISR. It introduced two categories of AD—conventional and unconventional—differing mainly in the manner of their causation. The former is caused by the neuronal ISR triggered by AβPP-derived iAβ, whereas in the latter, the neuronal ISR is elicited by stressors distinct from AβPP-derived iAβ and arising from brain trauma, viral and bacterial infections, and various types of inflammation. Moreover, conventional AD always contains an unconventional component, and in both forms, the disease is driven by iAβ generated independently of AβPP. In its third, the current, iteration, the ACH2.0 posits that proteolytic production of Aβ is suppressed in AD-affected neurons and that the disease is driven by C99 generated independently of AβPP. Suppression of Aβ production in AD seems an oxymoron: Aβ is equated with AD, and the later is inconceivable without the former in an ingrained Amyloid Cascade Hypothesis (ACH)-based notion. But suppression of Aβ production in AD-affected neurons is where the logic leads, and to follow it we only need to overcome the inertia of the preexisting assumptions. Moreover, not only is the generation of Aβ suppressed, so is the production of all components of the AβPP proteolytic pathway. This assertion is not a quantum leap (unless overcoming the inertia counts as such): the global cellular protein synthesis is severely suppressed under the neuronal ISR conditions, and there is no reason for constituents of the AβPP proteolytic pathway to be exempted, and they, apparently, are not, as indicated by the empirical data. In contrast, tau protein translation persists in AD-affected neurons under ISR conditions because the human tau mRNA contains an internal ribosomal entry site in its 5′UTR. In current mouse models, iAβ derived from AβPP expressed exogenously from human transgenes elicits the neuronal ISR and thus suppresses its own production. Its levels cannot principally reach AD pathology-causing levels regardless of the number of transgenes or the types of FAD mutations that they (or additional transgenes) carry. Since the AβPP-independent C99 production pathway is inoperative in mice, the current transgenic models have no potential for developing the full spectrum of AD pathology. What they display are only effects of the AβPP-derived iAβ-elicited neuronal ISR. The paper describes strategies to construct adequate transgenic AD models. It also details the utilization of human neuronal cells as the only adequate model system currently available for conventional and unconventional AD. The final alteration of the ACH2.0, introduced in the present Perspective, is that AβPP, which supports neuronal functionality and viability, is, after all, potentially produced in AD-affected neurons, albeit not conventionally but in an ISR-driven and -compatible process. Thus, the present narrative begins with the “omnipotent” Aβ capable of both triggering and driving the disease and ends up with this peptide largely dislodged from its pedestal and retaining its central role in triggering the disease in only one, although prevalent (conventional), category of AD (and driving it in none). Among interesting inferences of the present Perspective is the determination that “sporadic AD” is not sporadic at all (“non-familial” would be a much better designation). The term has fatalistic connotations, implying that the disease can strike at random. This is patently not the case: The conventional disease affects a distinct subpopulation, and the basis for unconventional AD is well understood. Another conclusion is that, unless prevented, the occurrence of conventional AD is inevitable given a sufficiently long lifespan. This Perspective also defines therapeutic directions not to be taken as well as auspicious ways forward. The former category includes ACH-based drugs (those interfering with the proteolytic production of Aβ and/or depleting extracellular Aβ). They are legitimate (albeit inefficient) preventive agents for conventional AD. There is, however, a proverbial snowball’s chance in hell of them being effective in symptomatic AD, lecanemab, donanemab, and any other “…mab” or “…stat” notwithstanding. They comprise Aβ-specific antibodies, inhibitors of beta- and gamma-secretase, and modulators of the latter. In the latter category, among ways to go are the following: (1) Depletion of iAβ, which, if sufficiently “deep”, opens up a tantalizing possibility of once-in-a-lifetime preventive transient treatment for conventional AD and aging-associated cognitive decline, AACD. (2) Composite therapy comprising the degradation of C99/iAβ and concurrent inhibition of the neuronal ISR. A single transient treatment could be sufficient to arrest the progression of conventional AD and prevent its recurrence for life. Multiple recurrent treatments would achieve the same outcome in unconventional AD. Alternatively, the sustained reduction/removal of unconventional neuronal ISR-eliciting stressors through the elimination of their source would convert unconventional AD into conventional one, preventable/treatable by a single transient administration of the composite C99/iAβ depletion/ISR suppression therapy. Efficient and suitable ISR inhibitors are available, and it is explicitly clear where to look for C99/iAβ-specific targeted degradation agents—activators of BACE1 and, especially, BACE2. Directly acting C99/iAβ-specific degradation agents such as proteolysis-targeting chimeras (PROTACs) and molecular-glue degraders (MGDs) are also viable options. (3) A circumscribed shift (either upstream or downstream) of the position of transcription start site (TSS) of the human AβPP gene, or, alternatively, a gene editing-mediated excision or replacement of a small, defined segment of its portion encoding 5′-untranslated region of AβPP mRNA; targeting AβPP RNA with anti-antisense oligonucleotides is another possibility. If properly executed, these RNA-based strategies would not interfere with the protein-coding potential of AβPP mRNA, and each would be capable of both preventing and stopping the AβPP-independent generation of C99 and thus of either preventing AD or arresting the progression of the disease in its conventional and unconventional forms. The paper is interspersed with “validation” sections: every conceptually significant notion is either validated by the existing data or an experimental procedure validating it is proposed. Full article

(This article belongs to the Special Issue Traumatic Brain Injury/Chronic Traumatic Encephalopathy as Cause of Alzheimer’s Disease: Physics and Molecular Biology in the Genesis of Neurodegeneration?)

15 pages, 1175 KiB

Open AccessFeature PaperArticle

Alternative Growing Media Under the Same Fertigation Scheme Affected Mineral Accumulation and Physiological Parameters in Grapevine Cultivars

by Nikolaos Tzortzakis and Antonios Chrysargyris

Horticulturae 2025, 11(5), 479; https://doi.org/10.3390/horticulturae11050479 (registering DOI) - 29 Apr 2025

Abstract

Under nursery conditions, various organic and inorganic growing media can be used for plant propagation. However, a common fertigation program may have varying effects on plant performance. This study evaluated alternative growing media under the same fertigation scheme in three indigenous Cypriot grapevine [...] Read more.

Under nursery conditions, various organic and inorganic growing media can be used for plant propagation. However, a common fertigation program may have varying effects on plant performance. This study evaluated alternative growing media under the same fertigation scheme in three indigenous Cypriot grapevine cultivars (Xynisteri, Maratheftiko, Giannoudi). Rooted cuttings were grown in pots containing soil, perlite, river sand, peat, and cocosoil. The plants were fertigated with a hydroponic nutrient solution with an electrical conductivity of 2.4 dS/m and a pH of 5.8. Xynisteri grown in peat and cocosoil accumulated minerals such as N and P while showing reduced levels of Na, total phenols, antioxidant capacity, and total flavonoids in the leaves. Additionally, plants exhibited low hydrogen peroxide and malondialdehyde (MDA) content, indicating a non-stressful growing environment. Maratheftiko cultivar accumulated N in perlite, K in cocosoil, and P in peat and cocosoil media. When grown in soil, Maratheftiko showed higher phenol content and increased antioxidant capacity, which is correlated with elevated oxidative stress (higher MDA). Giannoudi appeared to be more adapted to soil and/or cocosoil media, as evidenced by its lower MDA content, total phenols, total flavonoids, and antioxidant activity, compared to plants grown in perlite, sand, and peat. Chlorophyll and total carotenoid levels were increased in Giannoudi grown in soil. In conclusion, both growing media and fertigation practices should be tailored to optimize plant performance under nursery conditions. Full article

(This article belongs to the Special Issue Optimization of Horticultural Plant Production in Controlled Environments Using Proximal Sensing)

14 pages, 1794 KiB

Open AccessArticle

Feasibility of Photoplethysmography in Detecting Arterial Stiffness in Hypertension

by Parmis Karimpour, James M. May and Panicos A. Kyriacou

Photonics 2025, 12(5), 430; https://doi.org/10.3390/photonics12050430 (registering DOI) - 29 Apr 2025

Abstract

Asymptomatic peripheral artery disease (PAD) poses a silent risk, potentially leading to severe conditions if undetected. Integrating new screening tools into routine general practitioner (GP) visits could enable early detection. This study investigates the feasibility of photoplethysmography (PPG) monitoring for assessing vascular health [...] Read more.

Asymptomatic peripheral artery disease (PAD) poses a silent risk, potentially leading to severe conditions if undetected. Integrating new screening tools into routine general practitioner (GP) visits could enable early detection. This study investigates the feasibility of photoplethysmography (PPG) monitoring for assessing vascular health across different blood pressure (BP) conditions. Custom femoral artery phantoms representing healthy (0.82 MPa), intermediate (1.48 MPa), and atherosclerotic (2.06 MPa) vessels were tested under hypertensive, normotensive, and hypotensive conditions to evaluate PPG’s ability to distinguish between vascular states. Extracted features from the PPG signal, including amplitude, area under the curve (AUC), median upslope–downslope ratio, and median end datum difference, were analysed. Kruskal–Wallis tests revealed significant differences between healthy and unhealthy vessels across BP states, supporting PPG as a screening tool. The fiducial points from the second derivative of the photoplethysmography signal (SDPPG) were analysed. The ratio was most pronounced between healthy and unhealthy phantoms under hypertensive conditions (ranging from –2.13 to –2.06), suggesting a change in vascular wall distensibility. Under normotensive conditions, the difference in ratios between healthy and unhealthy phantoms was smaller (0.01), and no meaningful difference was observed under hypotensive conditions, suggesting the reduced sensitivity of this metric at lower perfusion pressures. Intermediate states were challenging to detect, particularly under hypotension, suggesting a need for further research. Nonetheless, this study highlights the promise of PPG monitoring in identifying vascular stiffness. Full article

18 pages, 3119 KiB

Open AccessArticle

A Standardized Framework to Estimate Drought-Induced Vulnerability and Its Temporal Variation in Woody Plants Based on Growth

by Antonio Gazol, Elisa Tamudo-Minguez, Cristina Valeriano, Ester González de Andrés, Michele Colangelo and Jesús Julio Camarero

Forests 2025, 16(5), 760; https://doi.org/10.3390/f16050760 (registering DOI) - 29 Apr 2025

Abstract

Forests and scrubland comprise a large proportion of terrestrial ecosystems and, due to the long lifespan of trees and shrubs, their capacity to grow and store carbon as lasting woody tissues is particularly sensitive to warming-enhanced drought occurrence. Climate change may trigger a [...] Read more.

Forests and scrubland comprise a large proportion of terrestrial ecosystems and, due to the long lifespan of trees and shrubs, their capacity to grow and store carbon as lasting woody tissues is particularly sensitive to warming-enhanced drought occurrence. Climate change may trigger a transition from forests to scrubland in many drylands during the coming decades due to the higher resilience of shrubs. However, we lack standardized frameworks to compare the response to drought of woody plants. We present a framework and develop an index to estimate the drought-induced vulnerability (DrVi) of trees and shrubs based on the radial growth trajectory and the response of growth variability to a drought index. We used tree-ring width series of three tree (Pinus halepensis Mill., Juniperus thurifera L., and Acer monspessulanum L.) and three shrub (Juniperus oxycedrus L., Pistacia lentiscus L., and Ephedra nebrodensis Tineo ex Guss.) species from semi-arid areas to test this framework. We compared the DrVi values between species and populations and explored their temporal changes. Across species, the strongest DrVi values were found in declining P. halepensis stands and J. oxycedrus from the same site, while the lowest DrVi values were found in A. monspessulanum, P. lentiscus, and E. nebrodensis. Across populations, J. oxycedrus presented higher vulnerability in one of the dry sites. The P. halepensis declining stand showed a steady increase in DrVi value after the 1980s as the climate shifted toward warmer and drier conditions. We conclude that the DrVi allows comparing species and populations using a standardized general framework. Full article

(This article belongs to the Special Issue Tree Growth and Physiological Properties Under Ongoing Global Climate Change: 2nd Edition)

31 pages, 2424 KiB

Open AccessReview

Expanding Application of Optical Coherence Tomography Beyond the Clinic: A Narrative Review

by Tutut Nurjanah, Milin Patel, Jessica Mar, David Holden, Spencer C. Barrett and Nicolas A. Yannuzzi

Diagnostics 2025, 15(9), 1140; https://doi.org/10.3390/diagnostics15091140 (registering DOI) - 29 Apr 2025

Abstract

Since its introduction, optical coherence tomography (OCT) has significantly progressed in addressing its limitations. By integrating artificial intelligence and multimodal imaging, OCT enhances both speed and image quality while reducing its size. OCT continues to advance, offering new possibilities beyond the in-office setting, [...] Read more.

Since its introduction, optical coherence tomography (OCT) has significantly progressed in addressing its limitations. By integrating artificial intelligence and multimodal imaging, OCT enhances both speed and image quality while reducing its size. OCT continues to advance, offering new possibilities beyond the in-office setting, including intraoperative applications. This review will explore the different types of home OCT and intraoperative OCT, as well as the uses of each device and their future potential in ophthalmology. Full article

(This article belongs to the Special Issue Optical Coherence Tomography in Diagnosis of Ophthalmology Disease)

22 pages, 3809 KiB

Open AccessArticle

Optimized Feedback Type Flux Weakening Control of Non-Salient Permanent Magnet Synchronous Machines in MTPV Region with Improved Stability

by Chao Wang, Ziqiang Zhu, Lei Xu, Ximeng Wu and Kejin Lu

Energies 2025, 18(9), 2282; https://doi.org/10.3390/en18092282 (registering DOI) - 29 Apr 2025

Abstract

This paper introduces an enhanced approach for optimizing the flux-weakening performance of a non-salient permanent magnet synchronous machine (PMSM), by incorporating the maximum torque per voltage (MTPV) region into a conventional voltage magnitude feedback control strategy. The MTPV control strategy is initially optimized [...] Read more.

This paper introduces an enhanced approach for optimizing the flux-weakening performance of a non-salient permanent magnet synchronous machine (PMSM), by incorporating the maximum torque per voltage (MTPV) region into a conventional voltage magnitude feedback control strategy. The MTPV control strategy is initially optimized for steady-state performance by incorporating the effect of resistance, which plays a crucial role in small power motors. To maintain stability and good dynamics in the flux-weakening region, a current command feedback MTPV controller is utilized, as opposed to a voltage command feedback approach. Additionally, to address stability concerns in the MTPV region, a feedback type proportional-integral (PI) MTPV controller is designed and implemented. The stability in both the over-modulation and various flux-weakening regions is further enhanced using a voltage vector modifier (VVM). Therefore, the proposed feedback-based flux-weakening control enhances system steady-state performance, dynamic response, and stability across both linear and over modulation regions under various flux-weakening conditions, making it suitable for general-purpose applications. The effectiveness of the proposed method is validated through experimental results. Full article

(This article belongs to the Special Issue Emerging Trends in Closed-Loop Control Systems for Electric Machines and Drives: From Classical Techniques to Smart Solutions)

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