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19 pages, 464 KiB

Open AccessArticle

The Impact of Deficit Irrigation on the Agronomic Performance and Chemical Composition of Scolymus hispanicus L.

by Nikolaos Polyzos, Beatriz H. Paschoalinotto, Tânia C. S. P. Pires, Mikel Añibarro-Ortega, Ricardo Calhelha, Isabel C. F. R. Ferreira, Maria Inês Dias, Lillian Barros and Spyridon A. Petropoulos

Horticulturae 2024, 10(5), 479; https://doi.org/10.3390/horticulturae10050479 (registering DOI) - 07 May 2024

Abstract

In the current study, the effects of drought stress on the growth and phytochemical profile of Scolymus hispanicus L. (a.k.a. golden thistle) were evaluated. Plants were treated with three irrigation regimes, e.g., plants that received only rainwater (Control; C), deficit irrigation (I1; 50% [...] Read more.

In the current study, the effects of drought stress on the growth and phytochemical profile of Scolymus hispanicus L. (a.k.a. golden thistle) were evaluated. Plants were treated with three irrigation regimes, e.g., plants that received only rainwater (Control; C), deficit irrigation (I1; 50% of field capacity (FC)), and full irrigation (Ι2; 100% of FC). The fresh weight of the rosette of leaves was not negatively impacted by deficit irrigation, whereas root development was severely restrained compared to control and I2 treatments. Drought stress conditions had a positive effect on the nutritional properties of the golden thistle since the treatments of control and deficit irrigation showed the highest content of macronutrients and energy. Oxalic acid was the richest organic acid, especially under the I1 regime. Similarly, α-tocopherol was the only identified vitamin E isoform, whose content was also doubled in I1 treatment. Raffinose, glucose, and sucrose were the most abundant free sugars in amounts that varied among the irrigation treatments, while the total and distinct free sugar content was the highest for the I1 treatment. The most abundant detected fatty acid compounds were α-linolenic acid, followed by palmitic and linoleic acid, with the highest amount being detected in C, I1, and I2 treatments, respectively. Flavonoids were the only class of polyphenols detected in golden thistle leaves, including mostly kaempferol and quercetin derivatives. The greatest antioxidant potency was shown for the control and I1 treatments (for OxHLIA and TBARS methods, respectively). The evaluated leaf samples recorded a varied antimicrobial effect for the different bacterial strains and fungi, whereas no cytotoxic, hepatotoxic, and anti-inflammatory effects against the tested cell lines were recorded. Finally, the mineral content of leaves was significantly affected by the irrigation regime, with Ca, Mg, Cu, and Zn being the highest for the I1 treatment, while the I2 treatment had the highest content of K, Fe, and Mn and the lowest Na content. In conclusion, deficit irrigation showed promising results since it improved the phytochemical content without compromising the fresh weight of leaves, and thus it could be suggested as a sustainable agronomic practice for producing high-added value products without significant constraints in growth development and yield parameters of golden thistle. Full article

(This article belongs to the Special Issue Horticultural Production under Drought Stress)

18 pages, 830 KiB

Open AccessArticle

Exploiting the Potential of Powdered Blends of Recovered Sunflower Seed Cake Phenolics and Whey—Development of Sustainable Food Additives

by Anna Michalska-Ciechanowska, Jessica Brzezowska, Krzysztof Lech, Klaudia Masztalerz, Malgorzata Korzeniowska, Aleksandra Zambrowicz and Marek Szoltysik

Foods 2024, 13(10), 1433; https://doi.org/10.3390/foods13101433 (registering DOI) - 07 May 2024

Abstract

The management of side streams from the food industry, especially oil and dairy by-products, has become an important issue linked to the European Commission’s recommendations for a circular economy. This study aimed to obtain sustainable food additives in the form of soluble-type powders [...] Read more.

The management of side streams from the food industry, especially oil and dairy by-products, has become an important issue linked to the European Commission’s recommendations for a circular economy. This study aimed to obtain sustainable food additives in the form of soluble-type powders composed of whey and recovered phenolics originating from sunflower seed cake. In order to valorise these di-blend products, the powders were characterised in terms of their physical, chemical, and sensory attributes. Based on the study findings, the addition of sunflower seed cake washouts (SSCWs) to whey (Wh) decreased the dry matter in the feed that affected the viscosity and drying yield. The addition of SSCWs did not have a significant effect on the physical properties of powders, except for colour. By-product management proposed in the study resulted in the production of nutritious and ready-to-use products in powder form with improved functional properties in terms of phenolic compounds and antioxidant capacity. The powders were sensorially appealing with a tangy sourness entwined with a delicate interplay of sweet and salty flavours, which can be easily incorporated into different types of foodstuffs. Full article

(This article belongs to the Special Issue Editorial Board Members’ Collection Series: "Food Design to Improve Quality and Sensory Aspects of Foods")

12 pages, 665 KiB

Open AccessArticle

Retinal Vascular Abnormalities and Clinical Parameters in Systemic Sclerosis

by Rosario Foti, Marco Zeppieri, Roberta Foti, Elisa Visalli, Giorgio Amato, Roberta Amato, Edoardo Dammino, Fabiana D’Esposito and Caterina Gagliano

J. Clin. Med. 2024, 13(10), 2738; https://doi.org/10.3390/jcm13102738 (registering DOI) - 07 May 2024

Abstract

Background: Systemic sclerosis is a complex autoimmune disease characterized by vasculopathy, fibrosis, and immune dysregulation. Ocular manifestations in these patients are increasingly recognized, suggesting potential correlations between systemic vascular abnormalities and ocular microvascular changes. Advancements in molecular immunology and imaging technology using [...] Read more.

Background: Systemic sclerosis is a complex autoimmune disease characterized by vasculopathy, fibrosis, and immune dysregulation. Ocular manifestations in these patients are increasingly recognized, suggesting potential correlations between systemic vascular abnormalities and ocular microvascular changes. Advancements in molecular immunology and imaging technology using ocular coherence tomography (OCT) have unveiled intricate pathways underlying possible disease pathogenesis. Understanding the interplay between retinal vascular abnormalities and molecular immunology parameters could provide insights into disease mechanisms and potential biomarkers. Purpose: The aim of this study was to investigate vascular abnormalities, detected with optical coherence tomography angiography (OCT-A), in systemic sclerosis patients and to find correlations between the severity of the disease detected with molecular immunology findings and OCT-A parameters. Methods: A group of 32 systemic sclerosis patients were compared with 9 healthy controls. Ganglion cell complex thickness (GCC), retina thickness of the fovea and parafovea, nerve fiber layer thickness (RNFL) and cup/disc area ratio were investigated using OCT. Vessel density (VD) of the superficial (SCP) and deep capillary plexus (DCP) of the whole macular area and ETDRS grid, size of the foveal avascular zone (FAZ) and vessel density of the radial peripapillary capillary plexus (RPCP) were evaluated using OCT-A. Modified Rodnan skin score (mRSS), capillaroscopy and disease duration were used to stage disease severity. Results: There was a statistically significant reduction in retina thickness of the fovea and parafovea, VD of the whole DCP, VD of the SCP and DCP in ETDRS grid in the patient group compared to controls (p < 0.001). The patients presented a significant enlargement of the FAZ (p 0.005). No significant correlation between OCT and OCT-A parameters and disease severity scores was found. Conclusions: OCT-A could represent a non-invasive tool to detect retinal microvascular damage in systemic sclerosis. Full article

(This article belongs to the Special Issue New Clinical Treatment for Ocular Vascular Disease and Fundus Disease)

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17 pages, 1175 KiB

Open AccessArticle

Rapid and Sensitive Detection of Inactivated SARS-CoV-2 Virus via Fiber-Optic and Electrochemical Impedance Spectroscopy Based Aptasensors

by Can Xiao, Nan Wang, Yuechao Zhao, Xuemei Liu, Hui Li, Aixue Huang, Lin Wang, Xinhui Lou, Bo Gao and Ningsheng Shao

Biosensors 2024, 14(5), 231; https://doi.org/10.3390/bios14050231 (registering DOI) - 07 May 2024

Abstract

The development of rapid detection tools for viruses is vital for the prevention of pandemics and biothreats. Aptamers that target inactivated viruses are attractive for sensors due to their improved biosafety. Here, we evaluated a DNA aptamer (named as 6.9) that specifically binds [...] Read more.

The development of rapid detection tools for viruses is vital for the prevention of pandemics and biothreats. Aptamers that target inactivated viruses are attractive for sensors due to their improved biosafety. Here, we evaluated a DNA aptamer (named as 6.9) that specifically binds to the inactivated SARS-CoV-2 virus with a low dissociation constant (K_D = 9.6 nM) for the first time. Based on aptamer 6.9, we developed a fiber-optic evanescent wave (FOEW) biosensor. Inactivated SARS-CoV-2 and the Cy5.5-tagged short complementary strand competitively bound with the aptamer immobilized on the surface of the sensor. The detection of the inactivated SARS-CoV-2 virus was realized within six minutes with a limit of detection (LOD, S/N = 3) of 740 fg/mL. We also developed an electrochemical impedance aptasensor which exhibited an LOD of 5.1 fg/mL and high specificity. We further demonstrated that the LODs of the FOEW and electrochemical impedance aptasensors were, respectively, more than 1000 and 100,000 times lower than those of commercial colloidal gold test strips. We foresee that the facile aptamer isolation process and sensor design can be easily extended for the detection of other inactivated viruses. Full article

(This article belongs to the Section Biosensors and Healthcare)

16 pages, 2901 KiB

Open AccessArticle

Piezoelectric Yield of Single Electrospun Poly(acrylonitrile) Ultrafine Fibers Studied by Piezoresponse Force Microscopy and Numerical Simulations

by Margherita Montorsi, Lorenzo Zavagna, Lorenzo Scarpelli, Bahareh Azimi, Simone Capaccioli, Serena Danti and Massimiliano Labardi

Polymers 2024, 16(10), 1305; https://doi.org/10.3390/polym16101305 (registering DOI) - 07 May 2024

Abstract

Quantitative converse piezoelectric coefficient (d₃₃) mapping of polymer ultrafine fibers of poly(acrylonitrile) (PAN), as well as of poly(vinylidene fluoride) (PVDF) as a reference material, obtained by rotating electrospinning, was carried out by piezoresponse force microscopy in the constant-excitation frequency-modulation mode [...] Read more.

Quantitative converse piezoelectric coefficient (d₃₃) mapping of polymer ultrafine fibers of poly(acrylonitrile) (PAN), as well as of poly(vinylidene fluoride) (PVDF) as a reference material, obtained by rotating electrospinning, was carried out by piezoresponse force microscopy in the constant-excitation frequency-modulation mode (CE-FM-PFM). PFM mapping of single fibers reveals their piezoelectric activity and provides information on its distribution along the fiber length. Uniform behavior is typically observed on a length scale of a few micrometers. In some cases, variations with sinusoidal dependence along the fiber are reported, compatibly with a possible twisting around the fiber axis. The observed features of the piezoelectric yield have motivated numerical simulations of the surface displacement in a piezoelectric ultrafine fiber concerned by the electric field generated by biasing of the PFM probe. Uniform alignment of the piezoelectric axis along the fiber would comply with the uniform but strongly variable values observed, and sinusoidal variations were occasionally found on the fibers laying on the conductive substrate. Furthermore, in the latter case, numerical simulations show that the piezoelectric tensor’s shear terms should be carefully considered in estimations since they may provide a remarkably different contribution to the overall deformation profile. Full article

(This article belongs to the Special Issue Electrospun Polymer Nanofibers: Preparation, Design, and Characterization)

21 pages, 4795 KiB

Open AccessArticle

Silver Complexes of Miconazole and Metronidazole: Potential Candidates for Melanoma Treatment

by Małgorzata Fabijańska, Agnieszka J. Rybarczyk-Pirek, Justyna Dominikowska, Karolina Stryjska, Dominik Żyro, Magdalena Markowicz-Piasecka, Małgorzata Iwona Szynkowska-Jóźwik, Justyn Ochocki and Joanna Sikora

Int. J. Mol. Sci. 2024, 25(10), 5081; https://doi.org/10.3390/ijms25105081 (registering DOI) - 07 May 2024

Abstract

Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new therapies that avoid the undesirable effects of pharmacological or medical treatment. This article discusses the chemical structures of [(MTZ)₂AgNO₃ [...] Read more.

Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new therapies that avoid the undesirable effects of pharmacological or medical treatment. This article discusses the chemical structures of [(MTZ)₂AgNO₃], [(MTZ)₂Ag]₂SO₄, [Ag(MCZ)₂NO₃], [Ag(MCZ)₂BF₄], [Ag(MCZ)₂SbF₆] and [Ag(MCZ)₂ClO₄] (MTZ—metronidazole; MCZ—miconazole) silver(I) compounds and the possible relationship between the molecules and their cytostatic activity against melanoma cells. Molecular Hirshfeld surface analysis and computational methods were used to examine the possible association between the structure and anticancer activity of the silver(I) complexes and compare the cytotoxicity of the silver(I) complexes of metronidazole and miconazole with that of silver(I) nitrate, cisplatin, metronidazole and miconazole complexes against A375 and BJ cells. Additionally, these preliminary biological studies found the greatest IC₅₀ values against the A375 line were demonstrated by [Ag(MCZ)₂NO₃] and [(MTZ)₂AgNO₃]. The compound [(MTZ)₂AgNO₃] was three-fold more toxic to the A375 cells than the reference (cisplatin) and 15 times more cytotoxic against the A375 cells than the normal BJ cells. Complexes of metronidazole with Ag(I) are considered biocompatible at a concentration below 50 µmol/L. Full article

(This article belongs to the Special Issue Recent Advances in Anti-Cancer Drugs)

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13 pages, 2072 KiB

Open AccessArticle

Electronically Temperature-Dependent Interplay between He and Trivacancy in Tungsten Plasma-Facing Materials

by Zhao-Zhong Fu and Bi-Cai Pan

Materials 2024, 17(10), 2182; https://doi.org/10.3390/ma17102182 (registering DOI) - 07 May 2024

Abstract

Both microvoids and helium (He) impurities are widely present in tungsten (W) plasma-facing materials (PFMs), where the interaction between microvoids and He atoms has led to the intriguing development of microvoids. In this paper, we comprehensively investigated the interaction between He atoms and [...] Read more.

Both microvoids and helium (He) impurities are widely present in tungsten (W) plasma-facing materials (PFMs), where the interaction between microvoids and He atoms has led to the intriguing development of microvoids. In this paper, we comprehensively investigated the interaction between He atoms and trivacancy (V3), a fundamental microvoid in W-PFMs, at the level of tight-binding theory. Our study showed that He atoms can catalyze the decomposition of the original V3 or facilitate its transformation into another V3 variant. We propose that a He atom near the V3 defect induces significant changes in the distribution of d-electron charges within the W atoms lining the inner wall of the V3 defect, making the W atom nearest to this He atom cationic and the other W atoms anionic. The attractive interaction between them promotes the decomposition and deformation of V3. As electronic excitation increases, the ionization of W atoms on the V3 wall gradually intensifies, thereby enhancing the cationic characteristics of the W atoms closest to the He atom. This process also prompts other W atoms to shift from anions to cations, leading to a transition in the electrostatic interactions between them from attraction to repulsion. This transformation, driven by electronic excitation, plays a significant inhibitory role in the decomposition and deformation of V3. Full article

(This article belongs to the Topic Advances in Computational Materials Sciences)

17 pages, 1185 KiB

Open AccessReview

Current Status of Research on Wildland Fire Impacts on Soil Environment and Soil Organisms and Hotspots Visualization Analysis

by Zhichao Cheng, Song Wu, Dan Wei, Hong Pan, Xiaoyu Fu, Xinming Lu and Libin Yang

Fire 2024, 7(5), 163; https://doi.org/10.3390/fire7050163 (registering DOI) - 07 May 2024

Abstract

Ecosystems are frequently disturbed by fires that have an important impact on the soil environment and the composition of soil organisms. In order to provide a baseline for the current research and identify trends on the effects of wildland fire on soil environment [...] Read more.

Ecosystems are frequently disturbed by fires that have an important impact on the soil environment and the composition of soil organisms. In order to provide a baseline for the current research and identify trends on the effects of wildland fire on soil environment and biological changes, the available literature was identified from the Web of Science database, covering the period from 1998/1998/1999 (the year of the earliest publication in this field) to 2023. A bibliometric analysis was performed and the data were visually displayed for the number of publications, countries, authors, research institutions, and keywords representing research hotspots. Specifically, the effects of wildland fire on the soil environment, on soil microorganisms and on soil fauna were analyzed. The results show that the annual number of publications describing effects of wildland fire on the soil environment and on soil microorganisms are increasing over time, while those describing effects on soil fauna are fewer and their number remains constant. The largest number of papers originate from the United States, with the United States Department of Agriculture as the research institution with the largest output. The three authors with the largest number of publications are Stefan H. Doerr, Manuel Esteban Lucas-Borja and Jan Jacob Keizer. The research hotspots, as identified by keywords, are highly concentrated on wildfire, fire, organic matter, and biodiversity, amongst others. This study comprehensively analyzes the current situation of the research on the effects of wildland fire on changes in the soil environment and organisms, and provides reference for relevant scientific researchers in this trend and future research hotspots. Full article

(This article belongs to the Special Issue Effects of Fires on Forest Ecosystems)

13 pages, 832 KiB

Open AccessArticle

Quality Characteristics of Raspberry By-Products for Sustainable Production

by Audrone Ispiryan, Ingrida Kraujutiene and Jonas Viskelis

Foods 2024, 13(10), 1436; https://doi.org/10.3390/foods13101436 (registering DOI) - 07 May 2024

Abstract

Raspberry seeds are a by-product of berries, both from their primary processing, such as in juice production, and secondary processing, such as in oil extraction. These seeds contain plenty of valuable components such as crude fiber, proteins, fats, and vitamins. Quality characterization is [...] Read more.

Raspberry seeds are a by-product of berries, both from their primary processing, such as in juice production, and secondary processing, such as in oil extraction. These seeds contain plenty of valuable components such as crude fiber, proteins, fats, and vitamins. Quality characterization is the initial step toward using these seeds as a sustainable and functional food. The aim of studying raspberry seeds’ quality profile, both before oil extraction and after different processing methods (supercritical CO₂, subcritical CO₂, cold pressing, and hexane solvent), is to point out the benefits of this by-product and to raise consumer awareness about their health and well-being benefits. This study provides evidence that raspberry seeds have good physical parameters for use in other products as a functional food enrichment ingredient, such as in baked goods, offering considerable health benefits due to their high nutrient content. The weights, peroxide values, moisture content, nutritional energy values, and colors were determined before oil extraction to give initial seed values. The nutrient content and amounts of macroelements, P, K, Ca, and Mg, as well as microelements, B, Zn, Cu, Fe, and Mn, were determined in the tested variety ‘Polka’, both before and after oil extractions and using different methods. The raspberry seeds’ moisture was 9.2%, their peroxide content was 5.64 mEq/kg, their nutritional value was 475.25 Kcal., and their total weight was 2.17 mg (1000 units). The seeds contain 7.4% protein, 22.1% crude fiber, 11.0% crude fat and oil, and 2.8% sugar. We determined how different oil extraction methods influence the nutrient, micro-, and macro-component values. We concluded that the seeds contained the highest manganese (45.3 mg/kg), iron (29.2 mg/kg), and zinc (17.4 mg/kg) contents and the lowest content of copper (5.1 mg/kg). This research shows that raspberry seeds represent a potential natural food ingredient, and after oil extraction with subcritical or supercritical CO₂ or cold pressing, they can be used as a sustainable and functional food. Full article

(This article belongs to the Section Food Security and Sustainability)

11 pages, 1671 KiB

Open AccessArticle

Determination of Microplastics in Omega-3 Oil Supplements

by Moonhae Kim, Juyang Kim, Seulah Park, Dowoon Kim, Jaehak Jung and Dongha Cho

Foods 2024, 13(10), 1434; https://doi.org/10.3390/foods13101434 (registering DOI) - 07 May 2024

Abstract

Microplastics (MPs) are ubiquitous in the environment, posing a threat to ecosystems and causing increasing concerns regarding their impacts on the human body through exposure. However, there has been limited research on the presence of MPs in functional foods, despite them being consumed [...] Read more.

Microplastics (MPs) are ubiquitous in the environment, posing a threat to ecosystems and causing increasing concerns regarding their impacts on the human body through exposure. However, there has been limited research on the presence of MPs in functional foods, despite them being consumed for health improvement. This study aimed to investigate MP occurrence in various omega-3 oils and oil products in the Korean market and its relation to the source of raw material or manufacture. MPs were investigated in omega-3 capsules and raw oil, sourced from both plant-based (PB) and animal-based (AB) sources. We developed a method of direct filtration with acetone washing for collecting and characterizing MPs larger than 5 μm using micro-Raman spectroscopy. The average number of MPs by mass was found to be 1.2 ± 1.7 MPs/g for PB raw oil, 2.2 ± 1.7 MPs/g for AB raw oil, 3.5 ± 3.9 MPs/g for PB capsule oil, and 10.6 ± 8.9 MPs/g for AB capsule oil. Polypropylene and polyethylene terephthalate were the major MP species (83–95%) found in omega-3 oil. The proportions based on size range remained consistent across all groups, with a trend of being detected at higher rates as the size decreased. The results reveal that the main reason for the MP contamination of omega-3 oil is not the source of raw material but the manufacturing and packaging process. Full article

(This article belongs to the Section Food Toxicology)

12 pages, 1497 KiB

Open AccessArticle

Fabrication of Ternary Titanium Dioxide/Polypyrrole/Phosphorene Nanocomposite for Supercapacitor Electrode Applications

by Seungho Ha and Keun-Young Shin

Molecules 2024, 29(10), 2172; https://doi.org/10.3390/molecules29102172 (registering DOI) - 07 May 2024

Abstract

In this paper, we report a titanium dioxide/polypyrrole/phosphorene (TiO₂/PPy/phosphorene) nanocomposite as an active material for supercapacitor electrodes. Black phosphorus (BP) was fabricated by ball milling to induce a phase transition from red phosphorus, and urea-functionalized phosphorene (urea-FP) was obtained by urea-assisted [...] Read more.

In this paper, we report a titanium dioxide/polypyrrole/phosphorene (TiO₂/PPy/phosphorene) nanocomposite as an active material for supercapacitor electrodes. Black phosphorus (BP) was fabricated by ball milling to induce a phase transition from red phosphorus, and urea-functionalized phosphorene (urea-FP) was obtained by urea-assisted ball milling of BP, followed by sonication. TiO₂/PPy/phosphorene nanocomposites can be prepared via chemical oxidative polymerization, which has the advantage of mass production for a one-pot synthesis. The specific capacitance of the ternary nanocomposite was 502.6 F g⁻¹, which was higher than those of the phosphorene/PPy (286.25 F g⁻¹) and TiO₂/PPy (150 F g⁻¹) nanocomposites. The PPy fully wrapped around the urea-FP substrate provides an electron transport pathway, resulting in the enhanced electrical conductivity of phosphorene. Furthermore, the assistance of anatase TiO₂ nanoparticles enhanced the structural stability and also improved the specific capacitance of the phosphorene. To the best of our knowledge, this is the first report on the potential of phosphorene hybridized with conducting polymers and metal oxides for practical supercapacitor applications. Full article

(This article belongs to the Special Issue Developments in Conducting Polymers: Applications for Electrochemistry)

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26 pages, 5102 KiB

Open AccessArticle

Research on Crack Propagation of Nitrate Ester Plasticized Polyether Propellant: Experiments and Simulation

by Hanwen Liu, Jiangning Wang and Xiaolong Fu

Materials 2024, 17(10), 2180; https://doi.org/10.3390/ma17102180 (registering DOI) - 07 May 2024

Abstract

To understand the fracture properties of the nitrate ester plasticized polyether (NEPE) propellant, single-edge notched tension (SENT) tests were carried out at room temperature (20 °C) under different tensile rates (10–500 mm/min). The mechanical response, crack morphology, evolution path, and crack propagation velocity [...] Read more.

To understand the fracture properties of the nitrate ester plasticized polyether (NEPE) propellant, single-edge notched tension (SENT) tests were carried out at room temperature (20 °C) under different tensile rates (10–500 mm/min). The mechanical response, crack morphology, evolution path, and crack propagation velocity during the fracture process were studied using a combination of a drawing machine and a high-speed camera. The mode I critical stress intensity factor K_I_c was calculated to analyze the tensile fracture toughness of the NEPE propellant, and a criterion related to K_I_c was proposed as a means of determining whether the solid rocket motors can normally work. The experimental results demonstrated that the NEPE propellant exhibited blunting fracture phenomena during crack propagation, resulting in fluctuating crack propagation velocity. The fracture toughness of the NEPE propellant exhibited clear rate dependence. When the tensile rate increased from 10 mm/min to 500 mm/min, the magnitude of the critical stress intensity factor increased by 62.3%. Moreover, numerical studies based on bond-based peridynamic (BBPD) were performed by modeling the fracture process of the NEPE propellant, including the crack propagation speed and the load–displacement curve of the NEPE propellant. The simulation results were then compared with the experiments. Full article

(This article belongs to the Special Issue Advances in Computational Modeling of Damage and Failure of Composite Materials)

9 pages, 224 KiB

Open AccessArticle

Temperature Effect of on the Growth and Development of Habrobracon hebetor Say (Hymenoptera: Braconidae) Reared on Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) Larvae

by Yong Huang, Wenjing Liu, Jianhua Lü, Wenkai Wang and Yafei Guo

Insects 2024, 15(5), 336; https://doi.org/10.3390/insects15050336 (registering DOI) - 07 May 2024

Abstract

Augmentative release of parasitoids has been an important component of integrated insect management for stored product protection. Understanding the effect of different temperatures on the growth and development of parasitoids is in favor of mass rearing of parasitoids. Habrobracon hebetor Say (Hymenoptera: Braconidae) [...] Read more.

Augmentative release of parasitoids has been an important component of integrated insect management for stored product protection. Understanding the effect of different temperatures on the growth and development of parasitoids is in favor of mass rearing of parasitoids. Habrobracon hebetor Say (Hymenoptera: Braconidae) is a highly cosmopolitan, gregarious ecto-parasitoid of a variety of Lepidopterous larvae. Thus, the growth and development of H. hebetor reared on Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) larvae were investigated at 15, 20, 25, 30, and 35 °C. Habrobracon hebetor could complete growth and development, and the developmental duration decreased with increasing temperature at 15, 20, 25, 30, and 35 °C. The development threshold temperatures of H. hebetor eggs, larvae, pupae, and egg-to-adult stages were 13.89, 6.39, 9.24, and 9.29 °C, and the effective accumulated temperatures were 23.33, 46.40, 142.68, and 240.31 °C·d, respectively. The total number of eggs laid by H. hebetor, the hatching rate of H. hebetor eggs, and the percentage of female offspring reached the maximum of 192.39, 83.89%, and 74.04% at 30 °C, respectively. There was no significant difference in pupal survival rate in the temperature range of 15 °C to 35 °C. At 30 °C, the pre-oviposition duration of H. hebetor was the shortest (0.87 d). Therefore, the optimal rearing temperature of H. hebetor was 30 °C. The present results are useful for the large-scale rearing of H. hebetor using E. elutella larvae as hosts and effectively implementing the biological control of stored-product insects. Full article

(This article belongs to the Special Issue Chemical and Non-chemical Control in Stored Product Protection: Modern Methods for Old Problems)

19 pages, 1702 KiB

Open AccessArticle

Analysis of Transient Thermoacoustic Characteristics and Performance in Carbon Nanotube Sponge Underwater Transducers

by Qianshou Qi, Zhe Li, Huilin Yin, Yanxia Feng, Zhenhuan Zhou and Dalun Rong

Nanomaterials 2024, 14(10), 817; https://doi.org/10.3390/nano14100817 (registering DOI) - 07 May 2024

Abstract

Recent advancements in marine technology have highlighted the urgent need for enhanced underwater acoustic applications, from sonar detection to communication and noise cancellation, driving the pursuit of innovative transducer technologies. In this paper, a new underwater thermoacoustic (TA) transducer made from carbon nanotube [...] Read more.

Recent advancements in marine technology have highlighted the urgent need for enhanced underwater acoustic applications, from sonar detection to communication and noise cancellation, driving the pursuit of innovative transducer technologies. In this paper, a new underwater thermoacoustic (TA) transducer made from carbon nanotube (CNT) sponge is designed to achieve wide bandwidth, high energy conversion efficiency, simple structure, good transient response, and stable sound response, utilizing the TA effect through electro-thermal modulation. The transducer has potential application in underwater acoustic communication. An electro-thermal-acoustic coupled simulation for the open model, sandwich model, and encapsulated model is presented to analyze the transient behaviors of CNT sponge TA transducers in liquid environments. The effects of key design parameters on the acoustic performances of both systems are revealed. The results demonstrate that a short pulse excitation with a low duty cycle could greatly improve the heat dissipation of the encapsulated transducer, especially when the thermoacoustic response time becomes comparable to thermal relaxation time. Full article

(This article belongs to the Special Issue Editorial Board Members’ Collection Series: Theory and Simulation of Nanostructures)

18 pages, 6447 KiB

Open AccessArticle

Study on the Impact of Tail Wing Profiles on the Resistance Characteristics of Amphibious Vehicles

by Zhongyuan Jiang, Jiangming Ding and Zhourui Li

J. Mar. Sci. Eng. 2024, 12(5), 780; https://doi.org/10.3390/jmse12050780 (registering DOI) - 07 May 2024

Abstract

The resistance performance of amphibious vehicles can be improved by installing underwater tail hydrofoils. The research on the impact of different hydrofoil profiles on the resistance characteristics of amphibious vehicles can provide a reference for the vehicle’s design. For an amphibious vehicle model, [...] Read more.

The resistance performance of amphibious vehicles can be improved by installing underwater tail hydrofoils. The research on the impact of different hydrofoil profiles on the resistance characteristics of amphibious vehicles can provide a reference for the vehicle’s design. For an amphibious vehicle model, five shapes of symmetrical hydrofoils, NACA0012, NACA0015, NACA0016, and asymmetric hydrofoils NACA23012, NACA66-209, were selected as the underwater tail wing of the vehicle body, respectively. Based on the RANS method and overset grid technology, the resistance performance of the vehicle body was numerically calculated, and the resistance variation in the amphibious vehicle equipped with different tail hydrofoils at 0.43 < Fr_∇ < 1.3 speed was obtained. The basic shape of amphibious vehicle tail wings can be determined by comparing the effects of symmetrical hydrofoils and asymmetric hydrofoils on body resistance. The results show that the asymmetric hydrofoils have a better resistance reduction effect on amphibious vehicles than the symmetrical ones. Among them, an amphibious vehicle installing the asymmetric hydrofoil NACA66-209 as an underwater tail wing can reduce resistance by 44.3%. Chord length is an important factor affecting the resistance reduction performance of tail wings. When Fr_∇ = 1.3, the asymmetric hydrofoil optimized based on chord length has a 21.2% higher resistance reduction effect on amphibious vehicles. Full article

(This article belongs to the Section Ocean Engineering)

19 pages, 987 KiB

Open AccessArticle

Copper(II), Nickel(II) and Zinc(II) Complexes of Peptide Fragments of Tau Protein

by Zsuzsa Kastal, Adrienn Balabán, Szilvia Vida, Csilla Kállay, Lajos Nagy, Katalin Várnagy and Imre Sóvágó

Molecules 2024, 29(10), 2171; https://doi.org/10.3390/molecules29102171 (registering DOI) - 07 May 2024

Abstract

Copper(II), nickel(II) and zinc(II) complexes of various peptide fragments of tau protein were studied by potentiometric and spectroscopic techniques. All peptides contained one histidyl residue and represented the sequences of tau(91–97) (Ac-AQPHTEI-NH₂), tau(385–390) (Ac-KTDHGA-NH₂) and tau(404–409) (Ac-SPRHLS-NH₂). [...] Read more.

Copper(II), nickel(II) and zinc(II) complexes of various peptide fragments of tau protein were studied by potentiometric and spectroscopic techniques. All peptides contained one histidyl residue and represented the sequences of tau(91–97) (Ac-AQPHTEI-NH₂), tau(385–390) (Ac-KTDHGA-NH₂) and tau(404–409) (Ac-SPRHLS-NH₂). Imidazole-N donors of histidine were the primary metal binding sites for all peptides and all metal ions, but in the case of copper(II) and nickel(II), the deprotonated amide groups were also involved in metal binding by increasing pH. The most stable complexes were formed with copper(II) ions, but the presence of prolyl residues resulted in significant changes in the thermodynamic stability and speciation of the systems. It was also demonstrated that nickel(II) and especially zinc(II) complexes have relatively low thermodynamic stability with these peptides. The copper(II)-catalyzed oxidation of the peptides was also studied. In the presence of H₂O₂, the fragmentation of peptides was detected in all cases. In the simultaneous presence of H₂O₂ and ascorbic acid, the fragmentation of the peptide is less preferred, and the formation of 2-oxo-histidine also occurs. Full article

(This article belongs to the Section Medicinal Chemistry)

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16 pages, 436 KiB

Open AccessReview

Effect of Boxing Exercises on the Functional Ability and Quality of Life of Individuals with Parkinson’s Disease: A Systematic Review

by Nikolaos Chrysagis, Georgia Trompouki, Dimitris Petropaulis, George A. Koumantakis, Georgios Krekoukias, Georgios Theotokatos, Emmanouil Skordilis and Vasiliki Sakellari

Eur. J. Investig. Health Psychol. Educ. 2024, 14(5), 1295-1310; https://doi.org/10.3390/ejihpe14050085 (registering DOI) - 07 May 2024

Abstract

Parkinson’s disease (PD) is a neurological disorder caused by the loss of dopamine-producing cells in the substantia nigra and characterized by motor and non-motor symptoms. Boxing is a type of complementary therapy to improve symptoms in PD. The purpose of the present study [...] Read more.

Parkinson’s disease (PD) is a neurological disorder caused by the loss of dopamine-producing cells in the substantia nigra and characterized by motor and non-motor symptoms. Boxing is a type of complementary therapy to improve symptoms in PD. The purpose of the present study was to examine the effect of boxing training on the functionality and quality of life of patients with PD. The literature search was performed on PubMed, Scopus, PEDro, Cochrane Library, and Google Scholar search engines. The PEDro scale was used to assess the methodological quality of the studies. This systematic review included three studies that examined disease severity, mobility, physical activity, balance, and quality of life. According to the PEDro scale criteria, the three articles included were of high methodological quality. Statistically significant improvements after the implementation of boxing training was shown for balance and quality of life in contrast to the other variables. Boxing training intervention programs had a positive effect on balance and quality of life in patients with PD; however, the results are conflicting regarding certain functionality variables. Therefore, it is necessary to conduct further research to examine the effectiveness of boxing training on the functionality and quality of life of patients with Parkinson’s disease. Full article

17 pages, 2420 KiB

Open AccessArticle

Elastic and Elastoplastic Contact Mechanics of Concentrated Coated Contacts

by Patricia M. Johns-Rahnejat, Nader Dolatabadi and Homer Rahnejat

Lubricants 2024, 12(5), 162; https://doi.org/10.3390/lubricants12050162 (registering DOI) - 07 May 2024

Abstract

Machines operate under increasingly harsher contact conditions, causing significant wear and contact fatigue. Sub-surface stresses are responsible for the premature contact fatigue of rolling element bearings, meshing gears, and cam–follower pairs. Surface protection measures include hard, wear-resistant coatings. Traditionally, contact integrity has been [...] Read more.

Machines operate under increasingly harsher contact conditions, causing significant wear and contact fatigue. Sub-surface stresses are responsible for the premature contact fatigue of rolling element bearings, meshing gears, and cam–follower pairs. Surface protection measures include hard, wear-resistant coatings. Traditionally, contact integrity has been predicted using classical Hertzian contact mechanics. However, the theory is only applicable when the contact between a pair of ellipsoidal solids of revolution may be considered as a rigid indenter penetrating a semi-infinite elastic half-space. Many coatings act as thin bonded elastic layers that undergo considerably higher pressures than those predicted by the classical theory. Furthermore, inelastic deformation of bonded solids can cause plastic flow, work-hardening, and elastoplastic behaviour. This paper presents a comprehensive, integrated contact mechanics analysis that includes induced sub-surface stresses in concentrated counterformal finite line contacts for all the aforementioned cases. Generated pressures and deformation are predicted for hard coated surfaces, for which there is a dearth of relevant analysis. The contact characteristics, which are of particular practical significance, of many hard, wear-resistant advanced coatings are also studied. The paper clearly demonstrates the importance of using efficient semi-analytical, detailed holistic contact mechanics rather than the classical idealised methods or empirical numerical ones such as FEA. The novel approach presented for the finite line contact of thin-layered bonded solids has not hitherto been reported in the open literature. Full article

(This article belongs to the Special Issue Selected Papers from the 8th Conference on Lubrication, Maintenance and Tribotechnology (LUBMAT))

52 pages, 4744 KiB

Open AccessArticle

Force Metrology with Plane Parallel Plates: Final Design Review and Outlook

by Hamid Haghmoradi, Hauke Fischer, Alessandro Bertolini, Ivica Galić, Francesco Intravaia, Mario Pitschmann, Raphael A. Schimpl and René I. P. Sedmik

Physics 2024, 6(2), 690-741; https://doi.org/10.3390/physics6020045 (registering DOI) - 07 May 2024

Abstract

During the past few decades, abundant evidence for physics beyond the two standard models of particle physics and cosmology was found. Yet, we are tapping in the dark regarding our understanding of the dark sector. For more than a century, open problems related [...] Read more.

During the past few decades, abundant evidence for physics beyond the two standard models of particle physics and cosmology was found. Yet, we are tapping in the dark regarding our understanding of the dark sector. For more than a century, open problems related to the nature of the vacuum remained unresolved. As well as the traditional high-energy frontier and cosmology, technological advancement provides complementary access to new physics via high-precision experiments. Among the latter, the Casimir And Non-Newtonian force EXperiment (Cannex) has successfully completed its proof-of-principle phase and is going to commence operation soon. Benefiting from its plane parallel plate geometry, both interfacial and gravity-like forces are maximized, leading to increased sensitivity. A wide range of dark sector forces, Casimir forces in and out of thermal equilibrium, and gravity can be tested. This paper describes the final experimental design, its sensitivity, and expected results. Full article

(This article belongs to the Special Issue 75 Years of the Casimir Effect: Advances and Prospects)

23 pages, 996 KiB

Open AccessArticle

Molecular Responses of the Eukaryotic Cell Line INT407 on the Internalized Campylobacter jejuni—The Other Side of the Coin

by Anita Steinbach, József Kun, Péter Urbán, Tamás Palkovics, Beáta Polgár and György Schneider

Pathogens 2024, 13(5), 386; https://doi.org/10.3390/pathogens13050386 (registering DOI) - 07 May 2024

Abstract

Campylobacter jejuni is a zoonotic bacterium with the capacity to invade the epithelial cells during the pathogenic process. Several bacterial factors have been identified to contribute to this process, but our knowledge is still very limited about the response of the host. To [...] Read more.

Campylobacter jejuni is a zoonotic bacterium with the capacity to invade the epithelial cells during the pathogenic process. Several bacterial factors have been identified to contribute to this process, but our knowledge is still very limited about the response of the host. To reveal the major routes of this response, a whole-transcriptome analysis (WTA) was performed where gene expressions were compared between the 1st and the 3rd hours of internalization in INT407 epithelial cells. From the 41,769 human genes tested, altogether, 19,060 genes were shown through WTA to be influenced to different extents. The genes and regulation factors of transcription (296/1052; 28%), signal transduction (215/1052; 21%), apoptosis (153/1052; 15%), immune responses (97/1052; 9%), transmembrane transport (64/1052; 6%), cell–cell signaling (32/1052; 3%), cell–cell adhesions (29/1052; 3%), and carbohydrate metabolism (28/1052; 3%) were the most affected biological functions. A striking feature of the gene expression of this stage of the internalization process is the activation of both immune functions and apoptosis, which convincingly outlines that the invaded cell faces a choice between death and survival. The seemingly balanced status quo between the invader and the host is the result of a complex process that also affects genes known to be associated with postinfectious pathological conditions. The upregulation of TLR3 (3.79×) and CD36 (2.73×), two general tumor markers, and SERPINEB9 (11.37×), FNDC1 (7.58×), and TACR2 (8.84×), three factors of tumorigenesis, confirms the wider pathological significance of this bacterium. Full article

(This article belongs to the Collection Campylobacter Infections Collection)

14 pages, 543 KiB

Open AccessArticle

Soil and Vegetation Characteristics of Grassland have a Greater Influence on the Abundance and Diversity of Earthworms than the Mowing Intensity in a Managed Nature Reserve

by Günther Kerschbaumer, Gerhard Karrer, Edith Gruber and Johann G. Zaller

Land 2024, 13(5), 627; https://doi.org/10.3390/land13050627 (registering DOI) - 07 May 2024

Abstract

Effects of mowing on vegetation parameters have been well studied. However, less is known about mowing effects on soil fauna and if soil properties alter this. We investigated earthworm communities in a long-term experiment 14 years after its establishment in 5 dry, fresh [...] Read more.

Effects of mowing on vegetation parameters have been well studied. However, less is known about mowing effects on soil fauna and if soil properties alter this. We investigated earthworm communities in a long-term experiment 14 years after its establishment in 5 dry, fresh and moist grassland plots located in the Natura 2000 site Lainzer Tiergarten near Vienna, Austria (238–402 m a.s.l., 48°10′ N, 16°12′ E). The grasslands were either mowed once a year or every second year, or not mowed since being established. Earthworms were assessed using the non-destructive octet electro-shocking method. Additionally, vegetation composition, soil conductivity, temperature and moisture were assessed. We found 13 earthworm species across all treatments, although their abundance was generally low with 6.1 ± 4.7 worms m⁻². The total earthworm abundance and species diversity was higher in dry compared to fresh and moist grasslands but was not affected by mowing frequency. Endogeic earthworms (Aporrectodea caliginosa, Aporrectodea rosea) and epigeics (Lumbricus rubellus) were more tolerant to mowing than anecics (Lumbricus terrestris, Allolobophora longa). Since plant species richness was highest in annually mown grasslands and earthworm species richness was positively related to plant species numbers, we recommend regular, low-input management to promote above- and belowground biodiversity in these grasslands. Full article

(This article belongs to the Special Issue Ecosystem Disturbances and Soil Properties)

14 pages, 5804 KiB

Open AccessArticle

Study on Multiple Effects of Self-Healing Properties and Thermal Characteristics of Asphalt Pavement

by Fan Zhang, Yuxuan Sun, Lingyun Kong, Augusto Cannone Falchetto, Dongdong Yuan and Weina Wang

Buildings 2024, 14(5), 1313; https://doi.org/10.3390/buildings14051313 (registering DOI) - 07 May 2024

Abstract

Asphalt pavements are prone to cracking in low-temperature environments, and microwave heating (MH) can heal the cracks effectively. This research mainly investigates the different MH effects on the self-healing properties of asphalt mixtures. With this objective, the three-point splitting test is conducted to [...] Read more.

Asphalt pavements are prone to cracking in low-temperature environments, and microwave heating (MH) can heal the cracks effectively. This research mainly investigates the different MH effects on the self-healing properties of asphalt mixtures. With this objective, the three-point splitting test is conducted to generate the cracks. A microwave oven is employed to heat the samples, and a thermal camera measures the surface temperature. Results indicate that heating power and time show a positive linear correlation with healing efficiency, and the HI of the samples can reach over 80%. The HI of the samples decreases with the heating cycle, but the sample with reasonable power and time still has a HI higher than 70% after 5 cycles. The temperature peaks on thermal images indicate that uneven heating exists during heating, but the heating uniformity is within an acceptable range. The healing efficiency level (HEL) suggests that asphalt mixtures have very low inefficient healing behavior if the heating time is below 45 s, but HEL can reach 86.14% at 700 W after 60 s. Furthermore, although the HI of strength shows ideal results, the recovery of other crack parameters, including stiffness, fracture energy, flexible index, and crack resistance index, are not satisfactory. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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17 pages, 719 KiB

Open AccessArticle

Studies on the Authorship of Albumen Vintage Photographs: A Combined Experimental and Chemometric Approach

by Monika Adamowska, Izabela Zając, Marek Grzegorz Sawicki and Wojciech Hyk

Molecules 2024, 29(10), 2170; https://doi.org/10.3390/molecules29102170 (registering DOI) - 07 May 2024

Abstract

The differences in albumen photographs from vintage photographic studios were identified by energy-dispersive X-ray fluorescence spectroscopy and Fourier transform infrared spectroscopy. The results inspired the concept of finding common features characteristic of a given photographic studio. The obtained measurement data (i.e., positions of [...] Read more.

The differences in albumen photographs from vintage photographic studios were identified by energy-dispersive X-ray fluorescence spectroscopy and Fourier transform infrared spectroscopy. The results inspired the concept of finding common features characteristic of a given photographic studio. The obtained measurement data (i.e., positions of vibrational bands for characteristic groups of albumen and the mass contents of chosen elements) were analyzed chemometrically by employing the Principal Component Analysis (PCA). The PCA technique allowed us to reduce the number of relevant experimental parameters characterizing the unique features of the photographic objects. The two major components were able to distinguish the photographic objects in terms of their authorship and the time to produce a photograph. The method developed was examined for a selected group of photographs consisting of albumen prints from three Polish photographic ateliers. To validate ED-XRF measurements and, consequently, the chemometric findings, reference albumen photo samples were designed and prepared. The empirical functional relationships between the content of photochemically reduced silver particles on the photographic paper and several physicochemical factors, including time of exposure to UV light, AgNO₃ concentration in a fixed bath, and concentrations of other additives, were proposed. These results can be used for the prediction of the experimental conditions under which the investigated photographs were developed. Full article

(This article belongs to the Section Photochemistry)

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