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16 pages, 6744 KiB  
Article
Thermochemical Conversion of Digestate Derived from OFMSW Anaerobic Digestion to Produce Methane-Rich Syngas with CO2 Sorption
by Emanuele Fanelli, Cesare Freda, Assunta Romanelli, Vito Valerio, Adolfo Le Pera, Miriam Sellaro, Giacinto Cornacchia and Giacobbe Braccio
Processes 2025, 13(8), 2451; https://doi.org/10.3390/pr13082451 (registering DOI) - 2 Aug 2025
Abstract
The energetic valorization of digestate obtained from anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) was investigated via pyrolysis in a bench-scale rotary kiln. The mass rate of dried digestate to the rotary kiln pyrolyzer was fixed at 500 [...] Read more.
The energetic valorization of digestate obtained from anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) was investigated via pyrolysis in a bench-scale rotary kiln. The mass rate of dried digestate to the rotary kiln pyrolyzer was fixed at 500 gr/h. The effect of the pyrolysis temperature was investigated at 600, 700, and 800 °C. The pyrolysis products, char, oil, and gas, were quantified and chemically analyzed. It was observed that with the increase in the temperature from 600 to 800 °C, the char decreased from 60.3% to 52.2% and the gas increased from 26.5% to 35.3%. With the aim of increasing the methane production and methane concentration in syngas, the effect of CaO addition to the pyrolysis process was investigated at the same temperature, too. The mass ratio CaO/dried digestate was set at 0.2. The addition of CaO sorbent has a clear effect on the yield and composition of pyrolysis products. Under the experimental conditions, CaO was observed to act both as a CO2 sorbent and as a catalyst, promoting cracking and reforming reactions of volatile compounds. In more detail, at the investigated temperatures, a net reduction in CO2 concentration was observed in syngas, accompanied by an increase in CH4 concentration. The gas yield decreased with the CaO addition because of CO2 chemisorption. The oil yield decreased as well, probably because of the cracking and reforming effect of the CaO on the volatiles. A very promising performance of the CaO sorbent was observed at 600 °C; at this temperature, the CO2 concentration decreased from 32.2 to 13.9 mol %, and the methane concentration increased from 16.1 to 29.4 mol %. At the same temperature, the methane production increased from 34 to 63 g/kgdigestate. Full article
(This article belongs to the Section Chemical Processes and Systems)
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15 pages, 1258 KiB  
Article
Synthesis and Evaluation of Sunflower-Oil-Based Esters as Biolubricant Base Oils Using Ca/TEA Alkoxide Catalyst
by Dimosthenis Filon, George Anastopoulos and Dimitrios Karonis
Lubricants 2025, 13(8), 345; https://doi.org/10.3390/lubricants13080345 (registering DOI) - 2 Aug 2025
Abstract
This study evaluates the production of base oils for biolubricants using fatty acid methyl esters (FAMEs) derived from sunflower oil as the raw material. The production process involved the synthesis of oleochemical esters through a single-step alkaline transesterification reaction with a high-molecular-weight polyol, [...] Read more.
This study evaluates the production of base oils for biolubricants using fatty acid methyl esters (FAMEs) derived from sunflower oil as the raw material. The production process involved the synthesis of oleochemical esters through a single-step alkaline transesterification reaction with a high-molecular-weight polyol, such as trimethylolpropane (TMP). To assess the effectiveness of the developed catalytic system in conducting the transesterification reactions and its impact on the properties of the final product, two types of alkaline catalysts were used. Specifically, the reactions were carried out using either Ca/TEA alkoxide or sodium methoxide as catalysts in various configurations and concentrations to determine the optimal catalyst concentration and reaction conditions. Sodium methoxide served as the commercial benchmark catalyst, while the Ca/TEA alkoxide was prepared in the laboratory. The optimal concentration of Ca/TEA was determined to be 3.0% wt. in the presence of iso-octane and 3.5% wt. under vacuum, while the corresponding concentrations of CH3ONa for both cases were determined to be 2.0% wt. The synthesized biolubricant esters exhibit remarkable performance characteristics, such as high kinematic viscosities and low pour points—ranging from 33–48 cSt at 40 °C, 7.68–10.03 cSt at 100 °C, to −14 to −7 °C, respectively—which are comparable to or improved over those of mineral oils such as SN-150 or SN-500, with the Ca/TEA alkoxide-catalyzed systems showing superior oxidation stability and reduced byproduct formation. Full article
(This article belongs to the Special Issue Tribological Properties of Biolubricants)
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21 pages, 5449 KiB  
Article
Comparisons of the Effects of Polymer and Alcohol Varnishes on Norway Spruce Wood Surface Modifications
by Mariana Domnica Stanciu, Maria Cristina Timar, Mircea Mihalcica, Mihaela Cosnita and Florin Dinulică
Polymers 2025, 17(15), 2131; https://doi.org/10.3390/polym17152131 (registering DOI) - 1 Aug 2025
Abstract
Spruce wood is a natural polymeric material, consisting of cellulose, lignin, hemicelluloses and other secondary components, which gives it a unique chemical footprint and architecture. Varnishes are used in musical instruments to protect the wood against humidity variations, wood being a hygroscopic material, [...] Read more.
Spruce wood is a natural polymeric material, consisting of cellulose, lignin, hemicelluloses and other secondary components, which gives it a unique chemical footprint and architecture. Varnishes are used in musical instruments to protect the wood against humidity variations, wood being a hygroscopic material, but also to protect the wood from dirt. The varnishes used both to protect the wood from resonance and to ensure a special aesthetic appearance are either polymeric varnishes (nitrocellulose, oil-based) or volatile solvents (spirit). In this study, the color changes, the surface morphology and the chemical spectrum produced by three types of varnishes, applied in 5, 10 and 15 layers, on resonance spruce plates were analyzed. The results revealed significant changes in the color parameters: the lightness decreased by approximately 17% after the first layer, by 50% after 5 layers, by 65% after 10 layers and by 70% after 15 layers. The color parameters are most influenced by the anatomical quality of spruce wood (annual ring width and earlywood/latewood ratio) in the case of oil-based varnishes and least influenced in the case of nitrocellulose varnishes. The chemical fingerprint was determined by FTIR spectrum analysis, which revealed that the most pronounced absorptions were the double band 2926–2858 cm−1, corresponding to aliphatic methylene and methyl groups (asymmetric and symmetrical C-H stretch), and the bands at 1724 cm−1 (oil-based varnish), 1722 cm−1 (nitrocellulose varnish) and 1708 cm−1 (spirit varnish), all assigned to non-conjugated carbonyl groups in either carboxylic acids, esters aldehydes or ketones. The novelty of the study lies in the comparative analysis of three types of varnishes used in the musical instrument industry, applied to samples of spruce resonance wood with different macroscopic characteristics in three different layer thicknesses. Full article
(This article belongs to the Special Issue Advances in Wood Based Composites, 2nd Edition)
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14 pages, 2514 KiB  
Article
The Transcriptional Coactivator DEAD/H Box 5 (DDX5) Gene Is a Target of the Transcription Factor E2F1 Deregulated from the Tumor Suppressor pRB
by Rinka Nakajima, Yaxuan Zhou, Mashiro Shirasawa, Mariana Fikriyanti, Ritsuko Iwanaga, Andrew P. Bradford, Kenta Kurayoshi, Keigo Araki and Kiyoshi Ohtani
Genes 2025, 16(8), 929; https://doi.org/10.3390/genes16080929 (registering DOI) - 1 Aug 2025
Abstract
Background: DEAD/H box 5 (DDX5) serves as a transcriptional coactivator for several transcription factors including E2F1, the primary target of the tumor suppressor pRB. E2F1 physiologically activated by growth stimulation activates growth-related genes and promotes cell proliferation. In contrast, upon loss of pRB [...] Read more.
Background: DEAD/H box 5 (DDX5) serves as a transcriptional coactivator for several transcription factors including E2F1, the primary target of the tumor suppressor pRB. E2F1 physiologically activated by growth stimulation activates growth-related genes and promotes cell proliferation. In contrast, upon loss of pRB function due to oncogenic changes, E2F1 is activated out of restraint by pRB (deregulated E2F1) and stimulates tumor suppressor genes such as ARF, which activates the tumor suppressor p53, to suppress tumorigenesis. We have recently reported that DDX5 augments deregulated E2F1 activity to induce tumor suppressor gene expression and apoptosis. During the analyses, we noted that over-expression of E2F1 increased DDX5 expression, suggesting a feed forward loop in E2F1 activation through DDX5. Objective: We thus examined whether the DDX5 gene is a target of deregulated E2F1. Method: For this purpose, we performed promoter analysis and ChIP assay. Result: The DDX5 promoter did not possess typical E2F binding consensus but contained several GC repeats observed in deregulated E2F1 targets. Insertion of point mutations in these GC repeats decreased responsiveness to deregulated E2F1 induced by over-expression of E2F1, but scarcely affected responsiveness to growth stimulation. ChIP assays showed that deregulated E2F1 induced by over-expression of E2F1 or expression of E1a, which binds pRB and releases E2F1, bound to the DDX5 gene, while physiological E2F1 induced by growth stimulation did not. Conclusions: These results suggest that the DDX5 gene is a target of deregulated E2F1, generating a feed forward loop mediating tumor suppressive E2F1 activity. Full article
(This article belongs to the Section Molecular Genetics and Genomics)
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20 pages, 10391 KiB  
Article
Sustainable Substitution of Petroleum-Based Processing Oils with Soybean-Derived Alternatives in Styrene–Butadiene Rubber: Effects on Processing Behavior and Mechanical Properties
by Yang-Wei Lin, Tsung-Yi Chen, Chen-Yu Chueh, Yi-Ting Chen, Tsunghsueh Wu and Hsi-Ming Hsieh
Polymers 2025, 17(15), 2129; https://doi.org/10.3390/polym17152129 (registering DOI) - 1 Aug 2025
Abstract
This study evaluates the replacement of petroleum-based naphthenic oil with four types of soybean-derived alternatives—virgin soybean oil (SBO), epoxidized SBO (ESBO), expired SBO, and recycled SBO—in styrene–butadiene rubber (SBR) composites. The materials were tested in both staining rubber (SR) and non-staining rubber (NSR) [...] Read more.
This study evaluates the replacement of petroleum-based naphthenic oil with four types of soybean-derived alternatives—virgin soybean oil (SBO), epoxidized SBO (ESBO), expired SBO, and recycled SBO—in styrene–butadiene rubber (SBR) composites. The materials were tested in both staining rubber (SR) and non-staining rubber (NSR) systems to assess processing characteristics, mechanical performance, and environmental durability. Among the alternatives, SBO demonstrated the best overall performance, improving processability and tensile strength by over 10%, while ESBO enhanced ozone resistance by 35% due to its epoxide functionality. Expired and recycled SBOs maintained essential mechanical properties within 90% of virgin SBO values. The full replacement of CH450 with SBO in tire prototypes resulted in burst strength exceeding 1000 kPa and stable appearance after 5000 km of road testing. To validate industrial relevance, the developed green tire was exhibited at the 2025 Taipei International Cycle Show, attracting interest from international buyers and stakeholders for its eco-friendly composition and carbon footprint reduction potential, thereby demonstrating both technical feasibility and commercial viability. Full article
(This article belongs to the Special Issue Functional Polymers and Their Composites for Sustainable Development)
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35 pages, 3599 KiB  
Review
Recent Advances in Borylation and Suzuki-Type Cross-Coupling—One-Pot Miyaura-Type CX and CH BorylationSuzuki Coupling Sequence
by Nouhaila Bahyoune, Mohammed Eddahmi, Perikleia Diamantopoulou, Ioannis D. Kostas and Latifa Bouissane
Catalysts 2025, 15(8), 738; https://doi.org/10.3390/catal15080738 (registering DOI) - 1 Aug 2025
Abstract
In the last decades, numerous approaches have been explored for the cross-coupling of biaryl building blocks depending on the presence of boron sources. In fact, these changes have been catalyzed by transition metal complexes. This review focuses on the progress of the last [...] Read more.
In the last decades, numerous approaches have been explored for the cross-coupling of biaryl building blocks depending on the presence of boron sources. In fact, these changes have been catalyzed by transition metal complexes. This review focuses on the progress of the last decade in transition metal-catalyzed C–X borylation and direct C–H borylation, with emphasis on nickel-catalyzed C–H borylation, as effective and affordable protocols for the borylation of aryl substrates. In addition, Suzuki-type cross-coupling by activation of C–H, C–C, or C–N bonds is also reported. This study then offers an overview of recent advances for the synthesis of bi- and multi-aryls found in synthetic molecular complexes and natural products using the transition metal-catalyzed one-pot Miyaura-type C–X and C–H borylation–Suzuki coupling sequence. Full article
(This article belongs to the Section Catalysis in Organic and Polymer Chemistry)
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22 pages, 4480 KiB  
Article
MGMR-Net: Mamba-Guided Multimodal Reconstruction and Fusion Network for Sentiment Analysis with Incomplete Modalities
by Chengcheng Yang, Zhiyao Liang, Tonglai Liu, Zeng Hu and Dashun Yan
Electronics 2025, 14(15), 3088; https://doi.org/10.3390/electronics14153088 (registering DOI) - 1 Aug 2025
Abstract
Multimodal sentiment analysis (MSA) faces key challenges such as incomplete modality inputs, long-range temporal dependencies, and suboptimal fusion strategies. To address these, we propose MGMR-Net, a Mamba-guided multimodal reconstruction and fusion network that integrates modality-aware reconstruction with text-centric fusion within an efficient state-space [...] Read more.
Multimodal sentiment analysis (MSA) faces key challenges such as incomplete modality inputs, long-range temporal dependencies, and suboptimal fusion strategies. To address these, we propose MGMR-Net, a Mamba-guided multimodal reconstruction and fusion network that integrates modality-aware reconstruction with text-centric fusion within an efficient state-space modeling framework. MGMR-Net consists of two core components: the Mamba-collaborative fusion module, which utilizes a two-stage selective state-space mechanism for fine-grained cross-modal alignment and hierarchical temporal integration, and the Mamba-enhanced reconstruction module, which employs continuous-time recurrence and dynamic gating to accurately recover corrupted or missing modality features. The entire network is jointly optimized via a unified multi-task loss, enabling simultaneous learning of discriminative features for sentiment prediction and reconstructive features for modality recovery. Extensive experiments on CMU-MOSI, CMU-MOSEI, and CH-SIMS datasets demonstrate that MGMR-Net consistently outperforms several baseline methods under both complete and missing modality settings, achieving superior accuracy, robustness, and generalization. Full article
(This article belongs to the Special Issue Application of Data Mining in Decision Support Systems (DSSs))
13 pages, 1247 KiB  
Article
Controlling Sodium Titanate Crystal Size to Improve Wettability and Early Osseointegration of Titanium Implants: Insights from an Animal Model
by Saray Fernández-Hernández, Javier Gil, Marta Sanjuán-Álvarez, Ignacio Sanz, Mariano Herrero-Climent and Aritza Brizuela-Velasco
J. Funct. Biomater. 2025, 16(8), 283; https://doi.org/10.3390/jfb16080283 (registering DOI) - 1 Aug 2025
Abstract
The thermo-chemical treatment of dental implants leads to the formation of sodium titanate crystals on their surface. When in contact with blood, these crystals dissolve and trigger an ionic exchange cascade, resulting in the formation of a calcium apatite layer. This study, carried [...] Read more.
The thermo-chemical treatment of dental implants leads to the formation of sodium titanate crystals on their surface. When in contact with blood, these crystals dissolve and trigger an ionic exchange cascade, resulting in the formation of a calcium apatite layer. This study, carried out both in vitro and in an animal model, aimed to determine whether the cooling rate of the treatment affects the size of the deposited crystals, and whether this in turn influences wettability and early bone-to-implant contact (BIC). A total of 50 dental implants and 50 titanium discs were treated using four different cooling rates, along with a control group. Crystal size was analyzed on implant surfaces using scanning electron microscopy, and wettability was assessed on titanium discs using a goniometer. Finally, the implants were placed in the tibiae of 13 rabbits, and histological analysis was performed after three weeks to compare BIC among groups. Results suggest that a cooling rate of 75 °C/h produces smaller sodium titanate crystals, which are associated with significantly improved surface wettability and a higher percentage of bone-to-implant contact after 3 weeks of healing (p < 0.05). Full article
(This article belongs to the Special Issue Biomaterials for Dental Reparative and Regenerative Therapies)
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20 pages, 15301 KiB  
Article
Application of CH241 Stainless Steel with High Concentration of Mn and Mo: Microstructure, Mechanical Properties, and Tensile Fatigue Life
by Ping-Yu Hsieh, Bo-Ding Wu and Fei-Yi Hung
Metals 2025, 15(8), 863; https://doi.org/10.3390/met15080863 (registering DOI) - 1 Aug 2025
Abstract
A novel stainless steel with high Mn and Mo content (much higher than traditional stainless steel), designated CH241SS, was developed as a potential replacement for Cr-Mo-V alloy steel in the cold forging applications of precision industry. Through carbon reduction in an environmentally friendly [...] Read more.
A novel stainless steel with high Mn and Mo content (much higher than traditional stainless steel), designated CH241SS, was developed as a potential replacement for Cr-Mo-V alloy steel in the cold forging applications of precision industry. Through carbon reduction in an environmentally friendly manner and a two-stage heat treatment process, the hardness of as-cast CH241 was tailored from HRC 37 to HRC 29, thereby meeting the industrial specifications of cold-forged steel (≤HRC 30). X-ray diffraction analysis of the as-cast microstructure revealed the presence of a small amount of ferrite, martensite, austenite, and alloy carbides. After heat treatment, CH241 exhibited a dual-phase microstructure consisting of ferrite and martensite with dispersed Cr(Ni-Mo) alloy carbides. The CH241 alloy demonstrated excellent high-temperature stability. No noticeable softening occurred after 72 h for the second-stage heat treatment. Based on the mechanical and room-temperature tensile fatigue properties of CH241-F (forging material) and CH241-ST (soft-tough heat treatment), it was demonstrated that the CH241 stainless steel was superior to the traditional stainless steel 4xx in terms of strength and fatigue life. Therefore, CH241 stainless steel can be introduced into cold forging and can be used in precision fatigue application. The relevant data include composition design and heat treatment properties. This study is an important milestone in assisting the upgrading of the vehicle and aerospace industries. Full article
(This article belongs to the Special Issue Advanced High Strength Steels: Properties and Applications)
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17 pages, 5323 KiB  
Review
Contrast-Enhanced Harmonic Endoscopic Ultrasonography for Prediction of Aggressiveness and Treatment Response in Patients with Pancreatic Lesions
by Marco Spadaccini, Gianluca Franchellucci, Marta Andreozzi, Maria Terrin, Matteo Tacelli, Piera Zaccari, Maria Chiara Petrone, Gaetano Lauri, Matteo Colombo, Valeria Poletti, Giacomo Marcozzi, Antonella Durante, Roberto Leone, Maria Margherita Massaro, Antonio Facciorusso, Alessandro Fugazza, Alessandro Repici, Paolo Giorgio Arcidiacono and Silvia Carrara
Cancers 2025, 17(15), 2545; https://doi.org/10.3390/cancers17152545 - 1 Aug 2025
Abstract
Endoscopic ultrasonography represents a crucial aspect of the diagnosis of pancreatic lesions. The echo-endoscopic features of pancreatic lesions, particularly their contrast behavior with the advent of Contrast-Enhanced EUS (CE-EUS) and Contrast Enhanced Harmonic-EUS (CH-EUS), can predict a lesion’s aggressiveness, depending on its nature. [...] Read more.
Endoscopic ultrasonography represents a crucial aspect of the diagnosis of pancreatic lesions. The echo-endoscopic features of pancreatic lesions, particularly their contrast behavior with the advent of Contrast-Enhanced EUS (CE-EUS) and Contrast Enhanced Harmonic-EUS (CH-EUS), can predict a lesion’s aggressiveness, depending on its nature. According to this, CH-EUS could be applied to structure an even more dedicated approach to patient care, for example, to ascertain eligibility for surgical intervention of a pancreatic ductal adenocarcinoma (PDAC) or the response to neoadjuvant chemotherapy in cases deemed borderline resectable. In addition to PDAC, other significant issues pertain to the management of small neuroendocrine tumors (NETs) and intraductal papillary mucinous neoplasms (IPMNs). In this context, CH-EUS can be crucial. The aim of this review is to underline the most recent evidence for EUS and CH-EUS applications in pancreatic lesion aggressiveness assessment and to focus on possible future research directions to further extend the application of CH-EUS in this field. Full article
(This article belongs to the Special Issue Clinical Applications of Ultrasound in Cancer Imaging and Treatment)
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11 pages, 2025 KiB  
Article
Remarkable Stability of Uropodina (Acari: Mesostigmata) Communities in Artificial Microhabitats: A Case Study of Bird Nest Boxes in Bory Tucholskie National Park
by Marta Kulczak, Jacek Wendzonka, Karolina Lubińska, Agnieszka Napierała and Jerzy Błoszyk
Diversity 2025, 17(8), 544; https://doi.org/10.3390/d17080544 (registering DOI) - 1 Aug 2025
Abstract
The presence of nest boxes not only increases the reproductive success of many passerine birds in transformed forest habitats, but they also constitute important artificial microhabitats for many groups of invertebrates. One of such groups which have been often found in this microhabitat [...] Read more.
The presence of nest boxes not only increases the reproductive success of many passerine birds in transformed forest habitats, but they also constitute important artificial microhabitats for many groups of invertebrates. One of such groups which have been often found in this microhabitat is saprophagous mites from the suborder Uropodina (Acari: Mesostigmata). The current study was conducted in October 2023 and 2024 in Bory Tucholskie National Park (BTNP) (northern Poland), where material from 137 tit (Paridae) and nuthatch (Sitta europaea) nest boxes was collected. The aim of this study was to analyse the stability of the communities of Uropodina in nest boxes in the park in two seasons and to determine whether the mite community structure within these nest boxes is similar in each year. The second aim was to analyse the abundance of Uropodina in relation to the composition of the nest box bedding material. This study revealed that the community in the scrutinised nest boxes was formed in both seasons by two species of nidicolous Uropodina species, i.e., Leiodinychus orbicularis (C.L. Koch, 1839) and Chiropturopoda nidiphila (Wiśniewski and Hirschmann, 1993), and that the species composition and the community structure were also very similar in both years. This study revealed that Ch. nidiphila dominated in the nest boxes with moss and grass, whereas L. orbicularis was most abundant in the boxes where the bedding was a mixture of mammalian hair and grass. However, no statistically significant differences in the abundance of these two mite species in both cases were revealed. Full article
(This article belongs to the Special Issue Diversity, Ecology, and Conservation of Mites)
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16 pages, 1365 KiB  
Article
Immobilization of Cd Through Biosorption by Bacillus altitudinis C10-4 and Remediation of Cd-Contaminated Soil
by Tianyu Gao, Chenlu Zhang, Xueqiang Hu, Tianqi Wang, Zhitang Lyu and Lei Sun
Microorganisms 2025, 13(8), 1798; https://doi.org/10.3390/microorganisms13081798 - 1 Aug 2025
Abstract
In this study, a highly cadmium (II)-resistant bacterium strain, C10-4, identified as Bacillus altitudinis, was isolated from a sediment sample collected from Baiyangdian Lake, China. The minimum inhibitory concentration (MIC) of Cd(II) for strain C10-4 was 1600 mg/L. Factors such as the [...] Read more.
In this study, a highly cadmium (II)-resistant bacterium strain, C10-4, identified as Bacillus altitudinis, was isolated from a sediment sample collected from Baiyangdian Lake, China. The minimum inhibitory concentration (MIC) of Cd(II) for strain C10-4 was 1600 mg/L. Factors such as the contact time, pH, Cd(II) concentration, and biomass dosage affected the adsorption of Cd(II) by strain C10-4. The adsorption process fit well to the Langmuir adsorption isotherm model and the pseudo-second-order kinetics model, based on the Cd(II) adsorption data obtained from the cells of strain C10-4. This suggests that Cd(II) is adsorbed by strain C10-4 cells via a single-layer homogeneous chemical adsorption process. According to the Langmuir model, the maximum biosorption capacity was 3.31 mg/g for fresh-strain C10-4 biomass. Cd(II) was shown to adhere to the bacterial cell wall through SEM-EDS analysis. FTIR spectroscopy further indicated that the main functional sites for the binding of Cd(II) ions on the cell surface of strain C10-4 were functional groups such as N-H, -OH, -CH-, C=O, C-O, P=O, sulfate, and phosphate. After the inoculation of strain C10-4 into Cd(II)-contaminated soils, there was a significant reduction (p < 0.01) in the exchangeable fraction of Cd and an increase (p < 0.01) in the sum of the reducible, oxidizable, and residual fractions of Cd. The results show that Bacillus altitudinis C10-4 has good potential for use in the remediation of Cd(II)-contaminated soils. Full article
(This article belongs to the Section Environmental Microbiology)
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23 pages, 5351 KiB  
Article
Hydrometallurgical Leaching of Copper and Cobalt from a Copper–Cobalt Ore by Aqueous Choline Chloride-Based Deep Eutectic Solvent Solutions
by Emmanuel Anuoluwapo Oke, Yorkabel Fedai and Johannes Hermanus Potgieter
Minerals 2025, 15(8), 815; https://doi.org/10.3390/min15080815 (registering DOI) - 31 Jul 2025
Abstract
The sustainable recovery of valuable metals such as Cu and Co from ores is a pressing need considering environmental and economic challenges. Therefore, this study evaluates the effectiveness of deep eutectic solvents (DESs) as alternative leaching agents for Cu and Co extraction. Four [...] Read more.
The sustainable recovery of valuable metals such as Cu and Co from ores is a pressing need considering environmental and economic challenges. Therefore, this study evaluates the effectiveness of deep eutectic solvents (DESs) as alternative leaching agents for Cu and Co extraction. Four DESs were prepared using choline chloride (ChCl) as a hydrogen bond acceptor (HBA) and oxalic acid (OA), ethylene glycol (EG), urea (U) and thiourea (TU) as hydrogen bond donors (HBDs). Leaching experiments were conducted with DESs supplemented with 30 wt.% water at varying temperatures, various solid-to-liquid ratios, and time durations. The ChCl:OA DES demonstrated the highest leaching efficiencies among the DESs tested on pure CuO and CoO, achieving 89.2% for Cu and 92.4% for Co (60 °C, 400 rpm, 6 h, −75 + 53 µm particle size, and 1:10 solid-to-liquid ratio). In addition, the dissolution kinetics, analysed using the shrinking core model (SCM), showed that the leaching process was mainly controlled by surface chemical reactions. The activation energy values for Cu and Co leaching were 46.8 kJ mol−1 and 51.4 kJ mol−1, respectively, supporting a surface chemical control mechanism. The results highlight the potential of ChCl:OA as a sustainable alternative for metal recovery. Full article
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17 pages, 1710 KiB  
Article
Physiological, Genetic, and Fermentative Traits of Oenococcus oeni Isolates from Spontaneous Malolactic Fermentation in Koshu Wine
by Misa Otoguro, Sayaka Inui, Taichi Aoyanagi, Ayana Misawa, Hiromi Nakano, Yoshimi Shimazu and Shigekazu Misawa
Fermentation 2025, 11(8), 440; https://doi.org/10.3390/fermentation11080440 (registering DOI) - 31 Jul 2025
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Abstract
Koshu wine, produced from the indigenous Japanese grape Vitis vinifera L. cv. Koshu exhibits a lower pH than other white wines, hindering malolactic fermentation (MLF) by lactic acid bacteria (LAB). Here, we aimed to isolate LAB strains capable of performing MLF under these [...] Read more.
Koshu wine, produced from the indigenous Japanese grape Vitis vinifera L. cv. Koshu exhibits a lower pH than other white wines, hindering malolactic fermentation (MLF) by lactic acid bacteria (LAB). Here, we aimed to isolate LAB strains capable of performing MLF under these challenging conditions to improve wine quality. Sixty-four Oenococcus oeni and one Lactobacillus hilgardii strain were isolated from Koshu grapes and wines that had undergone spontaneous MLF. MLF activity was assessed under varying pH, SO2, and ethanol conditions in modified basal medium (BM) and Koshu model wine media. Expression of stress-related genes was analyzed using real-time PCR. Carbon source utilization was evaluated via API 50CH assays. All isolates degraded malic acid and produced lactic acid at 15 °C and pH 3.2 in BM without reducing sugars. Seven strains, all identified as O. oeni, demonstrated MLF activity at pH 3.0 in modified BM lacking added reducing sugars or tomato juice. Six wine-derived strains tolerated up to 12% ethanol, whereas the grape-derived strain was inhibited at 10%. In a synthetic Koshu wine model (13% ethanol, pH 3.0), wine-derived isolates exhibited higher MLF activity than commercial starter strains. In high-performing strains, mleA was upregulated, and most isolates preferred fructose, arabinose, and ribose over glucose. These findings suggest that indigenous O. oeni strains from Koshu wine possess unique stress tolerance and metabolic traits, making them promising candidates for region-specific MLF starter cultures that could enhance Koshu wine quality and terroir expression. Full article
(This article belongs to the Special Issue Fermentation and Biotechnology in Wine Making)
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18 pages, 2612 KiB  
Article
Pressure Response of Crystalline Fluoranthene Probed by Raman Spectroscopy
by Olga Karabinaki, Stylianos Papastylianos, Nayra Machín Padrón, Antonios Hatzidimitriou, Dimitrios Christofilos and John Arvanitidis
Crystals 2025, 15(8), 697; https://doi.org/10.3390/cryst15080697 (registering DOI) - 30 Jul 2025
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Abstract
The pressure response and structural stability of fluoranthene crystals up to 8 GPa are investigated using Raman spectroscopy. The vast majority of the Raman peaks upshift with pressure, either sublinearly (intermolecular modes) or quasilinearly (intramolecular modes), reflecting the bond hardening upon volume contraction. [...] Read more.
The pressure response and structural stability of fluoranthene crystals up to 8 GPa are investigated using Raman spectroscopy. The vast majority of the Raman peaks upshift with pressure, either sublinearly (intermolecular modes) or quasilinearly (intramolecular modes), reflecting the bond hardening upon volume contraction. The frequency shifts, accompanied by intensity redistribution among the Raman peaks, are by far larger for the former than those for the latter vibrations, compatible with their nature: weak intermolecular van der Waals interactions and strong intramolecular covalent bonds. For pressures higher than 2 GPa, changes in the linear pressure coefficients of the Raman peak frequencies, mainly towards lower values, are observed. These are more pronounced for intermolecular and C–H stretching vibrations. For P > 4.7 GPa, the pressure coefficients are further reduced, while all the observed pressure-induced changes are fully reversible upon pressure release. These changes may be interpreted either as two structural transitions at ~2 and ~4.7 GPa or as a single, but sluggish, structural phase transition in the pressure range 2–4.7 GPa, featuring the reorientation and different stacking of the molecules. From the high-pressure Raman data in the low-pressure phase, a bulk modulus of ~7 GPa at ambient pressure is estimated for solid fluoranthene. Full article
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