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23 pages, 947 KiB  
Review
Relationship of S100 Proteins with Neuroinflammation
by Mario García-Domínguez
Biomolecules 2025, 15(8), 1125; https://doi.org/10.3390/biom15081125 (registering DOI) - 4 Aug 2025
Abstract
S100 proteins, a family of Ca2+-binding proteins, play numerous roles in cellular processes such as proliferation, differentiation, and apoptosis. Recent evidence has highlighted their critical involvement in neuroinflammation, a pathological hallmark of various neurodegenerative disorders including Alzheimer’s disease, multiple sclerosis, and [...] Read more.
S100 proteins, a family of Ca2+-binding proteins, play numerous roles in cellular processes such as proliferation, differentiation, and apoptosis. Recent evidence has highlighted their critical involvement in neuroinflammation, a pathological hallmark of various neurodegenerative disorders including Alzheimer’s disease, multiple sclerosis, and Parkinson’s disease. Among these proteins, S100B and S100A8/A9 are particularly implicated in modulating inflammatory responses in the CNS. Acting as DAMPs, they interact with pattern recognition receptors like RAGE and TLRs, triggering pro-inflammatory signaling cascades and glial activation. While low concentrations of S100 proteins may support neuroprotective functions, increased levels are often associated with exacerbated inflammation and neuronal damage. This review explores the dualistic nature of S100 proteins in neuroinflammatory processes, their molecular interactions, and their potential as biomarkers and therapeutic targets in neurodegenerative disease management. Full article
14 pages, 2981 KiB  
Article
LAMP-Based 4-Channel Microfluidic Chip for POCT Detection of Influenza A H1N1, H3N2, and Influenza B Victoria Viruses
by Xue Zhao, Jiale Gao, Yijing Gu, Zheng Teng, Xi Zhang, Huanyu Wu, Xin Chen, Min Chen and Jilie Kong
Biosensors 2025, 15(8), 506; https://doi.org/10.3390/bios15080506 (registering DOI) - 4 Aug 2025
Abstract
Background: Influenza viruses are major pathogens responsible for respiratory infections and pose significant risks to densely populated urban areas. RT-qPCR has made substantial contributions in controlling virus transmission during previous COVID-19 epidemics, but it faces challenges in terms of detection time for [...] Read more.
Background: Influenza viruses are major pathogens responsible for respiratory infections and pose significant risks to densely populated urban areas. RT-qPCR has made substantial contributions in controlling virus transmission during previous COVID-19 epidemics, but it faces challenges in terms of detection time for large sample sizes and susceptibility to nucleic acid contamination. Methods: Our study designed loop-mediated isothermal amplification primers for three common influenza viruses: A/H3N2, A/H1N1, and B/Victoria, and utilized a 4-channel microfluidic chip to achieve simultaneous detection. The chip initiates amplification by centrifugation and allows testing of up to eight samples at a time. Results: By creating a closed amplification system in the microfluidic chip, aerosol-induced nucleic acid contamination can be prevented through physically isolating the reaction from the operating environment. The chip can specifically detect A/H1N1, A/H3N2, and B/Victoria and has no signal for other common respiratory viruses. The testing process can be completed within 1 h and can be sensitive to viral RNA at concentrations as low as 10−3 ng/μL for A/H1N1 and A/H3N2 and 10−1 ng/μL for B/Victori. A total of 296 virus swab samples were further analyzed using the microfluidic chip method and compared with the classical qPCR method, which resulted in high consistency. Conclusions: Our chip enables faster detection of influenza virus and avoids nucleic acid contamination, which is beneficial for POCT establishment and has lower requirements for the operating environment. Full article
(This article belongs to the Section Nano- and Micro-Technologies in Biosensors)
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18 pages, 1188 KiB  
Review
Functional and Neuroplastic Effects of Cross-Education in Anterior Cruciate Ligament Rehabilitation: A Scoping Review with Bibliometric Analysis
by Jorge M. Vélez-Gutiérrez, Andrés Rojas-Jaramillo, Juan D. Ascuntar-Viteri, Juan D. Quintero, Francisco García-Muro San José, Bruno Bazuelo-Ruiz, Roberto Cannataro and Diego A. Bonilla
Appl. Sci. 2025, 15(15), 8641; https://doi.org/10.3390/app15158641 (registering DOI) - 4 Aug 2025
Abstract
Anterior cruciate ligament reconstruction (ACLR) results in prolonged muscle weakness, impaired neuromuscular control, and delayed return to sport. Cross-education (CE), unilateral training of the uninjured limb, has been proposed as an adjunct therapy to promote bilateral adaptations. This scoping review evaluated the functional [...] Read more.
Anterior cruciate ligament reconstruction (ACLR) results in prolonged muscle weakness, impaired neuromuscular control, and delayed return to sport. Cross-education (CE), unilateral training of the uninjured limb, has been proposed as an adjunct therapy to promote bilateral adaptations. This scoping review evaluated the functional and neuroplastic effects of CE rehabilitation post-ACLR. Following PRISMA-ScR and JBI guidelines, PubMed, Scopus, Web of Science, and PEDro were searched up to February 2025. A bibliometric analysis was also conducted to report keyword co-occurrence and identify trends in this line of research. Of 333 screened references, 14 studies (price index: 43% and low-to-moderate risk of bias) involving 721 participants (aged 17–45 years) met inclusion criteria. CE protocols (6–12 weeks; 2–5 sessions/week) incorporating isometric, concentric, and eccentric exercises demonstrated strength gains (10–31%) and strength preservation, alongside improved limb symmetry (5–14%) and dynamic balance (7–18%). There is growing interest in neuroplasticity and corticospinal excitability, although neuroplastic changes were assessed heterogeneously across studies. Findings support CE as a feasible and low-cost strategy to complement early-stage ACLR rehabilitation, especially when direct loading of the affected limb is limited. Standardized protocols for clinical intervention and neurophysiological assessment are needed. Full article
(This article belongs to the Special Issue Novel Approaches of Physical Therapy-Based Rehabilitation)
20 pages, 4989 KiB  
Article
Analysis of the Trade-Off/Synergy Effect and Driving Factors of Ecosystem Services in Hulunbuir City, China
by Shimin Wei, Jian Hou, Yan Zhang, Yang Tai, Xiaohui Huang and Xiaochen Guo
Agronomy 2025, 15(8), 1883; https://doi.org/10.3390/agronomy15081883 (registering DOI) - 4 Aug 2025
Abstract
An in-depth understanding of the spatiotemporal heterogeneity of ecosystem service (ES) trade-offs and synergies, along with their driving factors, is crucial for formulating key ecological restoration strategies and effectively allocating ecological environmental resources in the Hulunbuir region. This study employed an integrated analytical [...] Read more.
An in-depth understanding of the spatiotemporal heterogeneity of ecosystem service (ES) trade-offs and synergies, along with their driving factors, is crucial for formulating key ecological restoration strategies and effectively allocating ecological environmental resources in the Hulunbuir region. This study employed an integrated analytical approach combining the InVEST model, ArcGIS geospatial processing, R software environment, and Optimal Parameter Geographical Detector (OPGD). The spatiotemporal patterns and driving factors of the interaction of four major ES functions in Hulunbuir area from 2000 to 2020 were studied. The research findings are as follows: (1) carbon storage (CS) and soil conservation (SC) services in the Hulunbuir region mainly show a distribution pattern of high values in the central and northeast areas, with low values in the west and southeast. Water yield (WY) exhibits a distribution pattern characterized by high values in the central–western transition zone and southeast and low values in the west. For forage supply (FS), the overall pattern is higher in the west and lower in the east. (2) The trade-off relationships between CS and WY, CS and SC, and SC and WY are primarily concentrated in the western part of Hulunbuir, while the synergistic relationships are mainly observed in the central and eastern regions. In contrast, the trade-off relationships between CS and FS, as well as FS and WY, are predominantly located in the central and eastern parts of Hulunbuir, with the intensity of these trade-offs steadily increasing. The trade-off relationship between SC and FS is almost widespread throughout HulunBuir. (3) Fractional vegetation cover, mean annual precipitation, and land use type were the primary drivers affecting ESs. Among these factors, fractional vegetation cover demonstrates the highest explanatory power, with a q-value between 0.6 and 0.9. The slope and population density exhibit relatively weak explanatory power, with q-values ranging from 0.001 to 0.2. (4) The interactions between factors have a greater impact on the inter-relationships of ESs in the Hulunbuir region than individual factors alone. The research findings have facilitated the optimization and sustainable development of regional ES, providing a foundation for ecological conservation and restoration in Hulunbuir. Full article
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17 pages, 2479 KiB  
Article
Spectroscopic, Thermally Induced, and Theoretical Features of Neonicotinoids’ Competition for Adsorption Sites on Y Zeolite
by Bojana Nedić Vasiljević, Maja Milojević-Rakić, Maja Ranković, Anka Jevremović, Ljubiša Ignjatović, Nemanja Gavrilov, Snežana Uskoković-Marković, Aleksandra Janošević Ležaić, Hong Wang and Danica Bajuk-Bogdanović
Molecules 2025, 30(15), 3267; https://doi.org/10.3390/molecules30153267 (registering DOI) - 4 Aug 2025
Abstract
The competitive retention of pollutants in water tables determines their environmental fate and guides routes for their removal. To distinguish the fine differences in competitive binding at zeolite adsorption centers, a group of neonicotinoid pesticides is compared, relying on theoretical (energy of adsorption, [...] Read more.
The competitive retention of pollutants in water tables determines their environmental fate and guides routes for their removal. To distinguish the fine differences in competitive binding at zeolite adsorption centers, a group of neonicotinoid pesticides is compared, relying on theoretical (energy of adsorption, orientation, charge distribution) and experimental (spectroscopic and thermogravimetric) analyses for quick, inexpensive, and reliable screening. The MOPAC/QuantumEspresso platform was used for theoretical calculation, indicating close adsorption energy values for acetamiprid and imidacloprid (−2.2 eV), with thiamethoxam having a lower binding energy of −1.7 eV. FTIR analysis confirmed hydrogen bonding, among different dipole-dipole interactions, as the dominant adsorption mechanism. Due to their comparable binding energies, when the mixture of all three pesticides is examined, comparative adsorption capacities are evident at low concentrations, owing to the excellent adsorption performance of the FAU zeotype. At higher concentrations, competition for adsorption centers occurs, with the expected thiamethoxam binding being diminished due to the lower bonding energy. The catalytic impact of zeolite on the thermal degradation of pesticides is evidenced through TG analysis, confirming the adsorption capacities found by UV/VIS and HPLC/UV measurements. Detailed analysis of spectroscopic results in conjunction with theoretical calculation, thermal profiles, and UV detection offers a comprehensive understanding of neonicotinoids’ adsorption and can help with the design of future adsorbents. Full article
(This article belongs to the Special Issue Design, Synthesis, and Application of Zeolite Materials)
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31 pages, 4112 KiB  
Article
Can the Building Make a Difference to User’s Health in Indoor Environments? The Influence of PM2.5 Vertical Distribution on the IAQ of a Student House over Two Periods in Milan in 2024
by Yong Yu, Marco Gola, Gaetano Settimo and Stefano Capolongo
Atmosphere 2025, 16(8), 936; https://doi.org/10.3390/atmos16080936 (registering DOI) - 4 Aug 2025
Abstract
This study investigates indoor and outdoor air quality monitoring in a student dormitory located in northern Milan (Italy) using low-cost sensors. This research compares two monitoring periods in June and October 2024 to examine common PM2.5 vertical patterns and differences at the [...] Read more.
This study investigates indoor and outdoor air quality monitoring in a student dormitory located in northern Milan (Italy) using low-cost sensors. This research compares two monitoring periods in June and October 2024 to examine common PM2.5 vertical patterns and differences at the building level, as well as their influence on the indoor spaces at the corresponding positions. In each period, around 30 sensors were installed at various heights and orientations across indoor and outdoor spots for 2 weeks to capture spatial variations around the building. Meanwhile, qualitative surveys on occupation presence, satisfaction, and well-being were distributed in selected rooms. The analysis of PM2.5 data reveals that the building’s lower floors tended to have slightly higher outdoor PM2.5 concentrations, while the upper floors generally had lower PM2.5 indoor/outdoor (I/O) ratios, with the top-floor rooms often below 1. High outdoor humidity reduced PM infiltration, but when outdoor PM fell below 20 µg/m3 in these two periods, indoor sources became dominant, especially on the lower floors. Air pressure I/O differences had minimal impact on PM2.5 I/O ratios, though slightly positive indoor pressure might help prevent indoor PM infiltration. Lower ventilation in Period-2 possibly contributed to more reported symptoms, especially in rooms with higher PM from shared kitchens. While outdoor air quality affects IAQ, occupant behavior—especially window opening and ventilation management—remains crucial in minimizing indoor pollutants. Users can also manage exposure by ventilating at night based on comfort and avoiding periods of high outdoor PM. Full article
(This article belongs to the Special Issue Air Quality in Metropolitan Areas and Megacities (Second Edition))
8 pages, 4923 KiB  
Proceeding Paper
A Hardware Measurement Platform for Quantum Current Sensors
by Frederik Hoffmann, Ann-Sophie Bülter, Ludwig Horsthemke, Dennis Stiegekötter, Jens Pogorzelski, Markus Gregor and Peter Glösekötter
Eng. Proc. 2025, 101(1), 11; https://doi.org/10.3390/engproc2025101011 (registering DOI) - 4 Aug 2025
Abstract
A concept towards current measurement in low and medium voltage power distribution networks is presented. The concentric magnetic field around the current-carrying conductor should be measured using a nitrogen-vacancy quantum magnetic field sensor. A bottleneck in current measurement systems is the readout electronics, [...] Read more.
A concept towards current measurement in low and medium voltage power distribution networks is presented. The concentric magnetic field around the current-carrying conductor should be measured using a nitrogen-vacancy quantum magnetic field sensor. A bottleneck in current measurement systems is the readout electronics, which are usually based on optically detected magnetic resonance (ODMR). The idea is to have a hardware that tracks up to four resonances simultaneously for the detection of the three-axis magnetic field components and the temperature. Normally, expensive scientific instruments are used for the measurement setup. In this work, we present an electronic device that is based on a Zynq 7010 FPGA (Red Pitaya) with an add-on board, which has been developed to control the excitation laser, the generation of the microwaves, and interfacing the photodiode, and which provides additional fast digital outputs. The T1 measurement was chosen to demonstrate the ability to read out the spin of the system. Full article
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20 pages, 4055 KiB  
Article
Biphasic Salt Effects on Lycium ruthenicum Germination and Growth Linked to Carbon Fixation and Photosynthesis Gene Expression
by Xinmeng Qiao, Ruyuan Wang, Lanying Liu, Boya Cui, Xinrui Zhao, Min Yin, Pirui Li, Xu Feng and Yu Shan
Int. J. Mol. Sci. 2025, 26(15), 7537; https://doi.org/10.3390/ijms26157537 (registering DOI) - 4 Aug 2025
Abstract
Since the onset of industrialization, the safety of arable land has become a pressing global concern, with soil salinization emerging as a critical threat to agricultural productivity and food security. To address this challenge, the cultivation of economically valuable salt-tolerant plants has been [...] Read more.
Since the onset of industrialization, the safety of arable land has become a pressing global concern, with soil salinization emerging as a critical threat to agricultural productivity and food security. To address this challenge, the cultivation of economically valuable salt-tolerant plants has been proposed as a viable strategy. In the study, we investigated the physiological and molecular responses of Lycium ruthenicum Murr. to varying NaCl concentrations. Results revealed a concentration-dependent dual effect: low NaCl levels significantly promoted seed germination, while high concentrations exerted strong inhibitory effects. To elucidate the mechanisms underlying these divergent responses, a combined analysis of metabolomics and transcriptomics was applied to identify key metabolic pathways and genes. Notably, salt stress enhanced photosynthetic efficiency through coordinated modulation of ribulose 5-phosphate and erythrose-4-phosphate levels, coupled with the upregulation of critical genes encoding RPIA (Ribose 5-phosphate isomerase A) and RuBisCO (Ribulose-1,5-bisphosphate carboxylase/oxygenase). Under low salt stress, L. ruthenicum maintained intact cellular membrane structures and minimized oxidative damage, thereby supporting germination and early growth. In contrast, high salinity severely disrupted PS I (Photosynthesis system I) functionality, blocking energy flow into this pathway while simultaneously inducing membrane lipid peroxidation and triggering pronounced cellular degradation. This ultimately suppressed seed germination rates and impaired root elongation. These findings suggested a mechanistic framework for understanding L. ruthenicum adaptation under salt stress and pointed out a new way for breeding salt-tolerant crops and understanding the mechanism. Full article
(This article belongs to the Section Molecular Biology)
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23 pages, 4133 KiB  
Article
Re-Habiting the Rooftops in Ciutat Vella (Barcelona): Co-Designed Low-Cost Solutions for a Social, Technical and Environmental Improvement
by Marta Domènech-Rodríguez, Oriol París-Viviana and Còssima Cornadó
Urban Sci. 2025, 9(8), 304; https://doi.org/10.3390/urbansci9080304 - 4 Aug 2025
Abstract
This research addresses urban inequality by focusing on the rehabilitation of communal rooftops in Ciutat Vella, Barcelona, the city’s historic district, where residential vulnerability is concentrated in a particularly dense heritage urban environment with a shortage of outdoor spaces. Using participatory methodologies, this [...] Read more.
This research addresses urban inequality by focusing on the rehabilitation of communal rooftops in Ciutat Vella, Barcelona, the city’s historic district, where residential vulnerability is concentrated in a particularly dense heritage urban environment with a shortage of outdoor spaces. Using participatory methodologies, this research develops low-cost, removable, and recyclable prototypes aimed at improving social interaction, technical performance, and environmental conditions. The focus is on vulnerable populations, particularly the elderly. The approach integrates a bottom–up process and scalable solutions presented as a Toolkit of micro-projects. These micro-projects are designed to improve issues related to health, safety, durability, accessibility, energy savings, and acoustics. In addition, several possible material solutions for micro-projects are examined in terms of sustainability and cost. These plug-in interventions are designed for adaptability and replication throughout similar urban contexts and can significantly improve the quality of life for people, especially the elderly, in dense historic environments. Full article
14 pages, 1959 KiB  
Article
Influence of Molecular Weight of Anthraquinone Acid Dyes on Color Strength, Migration, and UV Protection of Polyamide 6 Fabrics
by Nawshin Farzana, Abu Naser Md Ahsanul Haque, Shamima Akter Smriti, Abu Sadat Muhammad Sayem, Fahmida Siddiqa, Md Azharul Islam, Md Nasim and S M Kamrul Hasan
Physchem 2025, 5(3), 31; https://doi.org/10.3390/physchem5030031 - 4 Aug 2025
Abstract
Anthraquinone acid dyes are widely used in dyeing polyamide due to their good exhaustion and brightness. While ionic interactions primarily govern dye–fiber bonding, the molecular weight (Mw) of these dyes can significantly influence migration, apparent color strength, and fastness behavior. This study offers [...] Read more.
Anthraquinone acid dyes are widely used in dyeing polyamide due to their good exhaustion and brightness. While ionic interactions primarily govern dye–fiber bonding, the molecular weight (Mw) of these dyes can significantly influence migration, apparent color strength, and fastness behavior. This study offers comparative insight into how the Mw of structurally similar anthraquinone acid dyes impacts their diffusion, fixation, and functional outcomes (e.g., UV protection) on polyamide 6 fabric, using Acid Blue 260 (Mw~564) and Acid Blue 127:1 (Mw~845) as representative low- and high-Mw dyes. The effects of dye concentration, pH, and temperature on color strength (K/S) were evaluated, migration index and zeta potential were measured, and UV protection factor (UPF) and FTIR analyses were used to assess fabric functionality. Results showed that the lower-Mw dye exhibited higher migration tendency, particularly at increased dye concentrations, while the higher-Mw dye demonstrated greater color strength and superior wash fastness. Additionally, improved UPF ratings were associated with higher-Mw dye due to enhanced light absorption. These findings offer practical insights for optimizing acid dye selection in polyamide coloration to balance color performance and functional attributes. Full article
(This article belongs to the Section Surface Science)
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15 pages, 1474 KiB  
Article
Decline in Serum Lysophosphatidylcholine Species in Patients with Severe Inflammatory Bowel Disease
by Hauke Christian Tews, Tanja Elger, Muriel Huss, Johanna Loibl, Arne Kandulski, Martina Müller, Marcus Höring, Gerhard Liebisch and Christa Buechler
J. Clin. Med. 2025, 14(15), 5485; https://doi.org/10.3390/jcm14155485 (registering DOI) - 4 Aug 2025
Abstract
Background/Objectives: Lysophosphatidylcholine (LPC) is composed of various lipid species, some of which exert pro-inflammatory and others anti-inflammatory activities. However, most of the LPC species analyzed to date are reduced in the serum of patients with inflammatory bowel disease (IBD) compared to healthy [...] Read more.
Background/Objectives: Lysophosphatidylcholine (LPC) is composed of various lipid species, some of which exert pro-inflammatory and others anti-inflammatory activities. However, most of the LPC species analyzed to date are reduced in the serum of patients with inflammatory bowel disease (IBD) compared to healthy controls. To our knowledge, the correlation between serum LPC species levels and measures of inflammation, as well as their potential as markers for monitoring IBD activity, has not yet been investigated. Methods: Thirteen LPC species, varying in acyl chain length and number of double bonds, were measured in the serum of 16 controls and the serum of 57 patients with IBD. Associations with C-reactive protein (CRP) and fecal calprotectin levels as markers of IBD severity were assessed. Results: Serum levels of LPC species did not differ between the healthy controls and the entire patient cohort. In patients with IBD, serum levels of LPC 16:1, 18:0, 18:3, 20:3, and 20:5, as well as total LPC concentrations, showed inverse correlations with both CRP and fecal calprotectin levels, indicating an association with inflammatory activity. Nine LPC species were significantly reduced in patients with high fecal calprotectin compared to those with low values. LPC species with 22 carbon atoms and 4 to 6 double bonds were not related to disease activity. Stool consistency and gastrointestinal symptoms did not influence serum LPC profiles. Corticosteroid treatment was associated with lower serum LPC 20:3 and 22:5 levels, while mesalazine, anti-TNF, and anti-IL-12/23 therapies had no significant impact on LPC concentrations. There was a strong positive correlation between LPC species containing 15 to 18 carbon atoms and serum cholesterol, triglycerides, and phosphatidylcholine levels. However, there was no correlation with markers of liver disease. Conclusions: Shorter-chain LPC species are reduced in patients with active IBD and reflect underlying hypolipidemia. While these lipid alterations provide insight into IBD-associated metabolic changes, they appear unsuitable as diagnostic or disease monitoring biomarkers. Full article
(This article belongs to the Special Issue Inflammatory Bowel Disease: Pathogenesis and Management Strategies)
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17 pages, 4153 KiB  
Article
Spherical Indentation Behavior of DD6 Single-Crystal Nickel-Based Superalloy via Crystal Plasticity Finite Element Simulation
by Xin Hao, Peng Zhang, Hao Xing, Mengchun You, Erqiang Liu, Xuegang Xing, Gesheng Xiao and Yongxi Tian
Materials 2025, 18(15), 3662; https://doi.org/10.3390/ma18153662 (registering DOI) - 4 Aug 2025
Abstract
Nickel-based superalloys are widely utilized in critical hot-end components, such as aeroengine turbine blades, owing to their exceptional high-temperature strength, creep resistance, and oxidation resistance. During service, these components are frequently subjected to complex localized loading, leading to non-uniform plastic deformation and microstructure [...] Read more.
Nickel-based superalloys are widely utilized in critical hot-end components, such as aeroengine turbine blades, owing to their exceptional high-temperature strength, creep resistance, and oxidation resistance. During service, these components are frequently subjected to complex localized loading, leading to non-uniform plastic deformation and microstructure evolution within the material. Combining nanoindentation experiments with the crystal plasticity finite element method (CPFEM), this study systematically investigates the effects of loading rate and crystal orientation on the elastoplastic deformation of DD6 alloy under spherical indenter loading. The results indicate that the maximum indentation depth increases and hardness decreases with prolonged loading time, exhibiting a significant strain rate strengthening effect. The CPFEM model incorporating dislocation density effectively simulates the nonlinear characteristics of the nanoindentation process and elucidates the evolution of dislocation density and slip system strength with indentation depth. At low loading rates, both dislocation density and slip system strength increase with loading time. Significant differences in mechanical behavior are observed across different crystal orientations, which correspond to the extent of lattice rotation during texture evolution. For the [111] orientation, crystal rotation is concentrated and highly regular, while the [001] orientation shows uniform texture evolution. This demonstrates that anisotropy governs the deformation mechanism through differential slip system activation and texture evolution. Full article
(This article belongs to the Special Issue Nanoindentation in Materials: Fundamentals and Applications)
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21 pages, 2139 KiB  
Article
Reclaimed Municipal Wastewater Sand as a Viable Aggregate in Cement Mortars: Alkaline Treatment, Performance, Assessment, and Circular Construction Applications
by Beata Łaźniewska-Piekarczyk and Monika Jolanta Czop
Processes 2025, 13(8), 2463; https://doi.org/10.3390/pr13082463 - 4 Aug 2025
Abstract
This study evaluates the potential use of reclaimed sand from municipal wastewater treatment plants (WWTP), categorized as waste under code 19 08 02, as a full substitute for natural sand in cement mortars. The sand was subjected to alkaline pretreatment using sodium hydroxide [...] Read more.
This study evaluates the potential use of reclaimed sand from municipal wastewater treatment plants (WWTP), categorized as waste under code 19 08 02, as a full substitute for natural sand in cement mortars. The sand was subjected to alkaline pretreatment using sodium hydroxide (NaOH) at concentrations of 0.5%, 1% and 2% to reduce organic impurities and improve surface cleanliness. All mortar mixes were prepared using CEM I 42.5 R as the binder, maintaining a constant water-to-cement ratio of 0.5. Mechanical testing revealed that mortars produced with 100% WWTP-derived sand, pretreated with 0.5% NaOH, achieved a mean compressive strength of 51.9 MPa and flexural strength of 5.63 MPa after 28 days, nearly equivalent to reference mortars with standardized construction sand (52.7 MPa and 6.64 MPa, respectively). In contrast, untreated WWTP sand resulted in a significant performance reduction, with compressive strength averaging 30.0 MPa and flexural strength ranging from 2.55 to 2.93 MPa. The results demonstrate that low-alkaline pretreatment—particularly with 0.5% NaOH—allows for the effective reuse of WWTP waste sand (code 19 08 02) in cement mortars based on CEM I 42.5 R, achieving performance comparable to conventional materials. Although higher concentrations, such as 2% NaOH, are commonly recommended or required by standards for the removal of organic matter from fine aggregates, the results suggest that lower concentrations (e.g., 0.5%) may offer a better balance between cleaning effectiveness and mechanical performance. Nevertheless, 2% NaOH remains the obligatory reference level in some standard testing protocols for fine aggregate purification. Full article
(This article belongs to the Special Issue Sustainable Development of Energy and Environment in Buildings)
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19 pages, 2474 KiB  
Article
Unraveling the Role of Aluminum in Boosting Lithium-Ionic Conductivity of LLZO
by Md Mozammal Raju, Yi Ding and Qifeng Zhang
Electrochem 2025, 6(3), 29; https://doi.org/10.3390/electrochem6030029 - 4 Aug 2025
Abstract
The development of high-performance solid electrolytes is critical to advancing solid-state lithium-ion batteries (SSBs), with lithium lanthanum zirconium oxide (LLZO) emerging as a leading candidate due to its chemical stability and wide electrochemical window. In this study, we systematically investigated the effects of [...] Read more.
The development of high-performance solid electrolytes is critical to advancing solid-state lithium-ion batteries (SSBs), with lithium lanthanum zirconium oxide (LLZO) emerging as a leading candidate due to its chemical stability and wide electrochemical window. In this study, we systematically investigated the effects of cation dopants, including aluminum (Al3+), tantalum (Ta5+), gallium (Ga3+), and rubidium (Rb+), on the structural, electronic, and ionic transport properties of LLZO using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. It appeared that, among all simulated results, Al-LLZO exhibits the highest ionic conductivity of 1.439 × 10−2 S/cm with reduced activation energy of 0.138 eV, driven by enhanced lithium vacancy concentrations and preserved cubic-phase stability. Ta-LLZO follows, with a conductivity of 7.12 × 10−3 S/cm, while Ga-LLZO and Rb-LLZO provide moderate conductivity of 3.73 × 10−3 S/cm and 3.32 × 10−3 S/cm, respectively. Charge density analysis reveals that Al and Ta dopants facilitate smoother lithium-ion migration by minimizing electrostatic barriers. Furthermore, Al-LLZO demonstrates low electronic conductivity (1.72 × 10−8 S/cm) and favorable binding energy, mitigating dendrite formation risks. Comparative evaluations of radial distribution functions (RDFs) and XRD patterns confirm the structural integrity of doped systems. Overall, Al emerges as the most effective and economically viable dopant, optimizing LLZO for scalable, durable, and high-conductivity solid-state batteries. Full article
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13 pages, 2036 KiB  
Article
Aluminum Extractions by the Alkali Method Directly from Alkali-Acid (NaOH-HCl) Chemical Deashing of Coals
by Lijun Zhao
Materials 2025, 18(15), 3661; https://doi.org/10.3390/ma18153661 (registering DOI) - 4 Aug 2025
Abstract
An advanced alkali-acid (NaOH-HCl) chemical method was used to deash aluminum-rich coals (ARCs) with a high ash content of 27.47 wt% to achieve a low ash content of 0.46 wt%. In the deashing process, aluminum in the coal ashes was dissolved in both [...] Read more.
An advanced alkali-acid (NaOH-HCl) chemical method was used to deash aluminum-rich coals (ARCs) with a high ash content of 27.47 wt% to achieve a low ash content of 0.46 wt%. In the deashing process, aluminum in the coal ashes was dissolved in both alkali solutions and acid solutions. The deashing alkali solutions with dissolved coal ashes were regenerated by adding CaO, and the resulting precipitates were added with sodium bicarbonate for aluminum extraction. High temperatures increased aluminum extraction, and excessive sodium bicarbonate addition decreased aluminum extraction. The deashing acid solutions were concentrated by evaporation, and silica gels formed during the process. The obtained mixtures were calcinated at 350 °C for the decomposition of aluminum chlorides, and soaked with water at 60 °C to remove the soluble chlorides. For the insoluble oxides after soaking, diluted alkali solutions were used to extract the aluminum at 90 °C, and aluminum extraction failed due to the formation of albite in the presence of sodium, aluminum and silicon elements as proved by XRD and SEM/EDS. When silica gels were separated by pressure filtering, aluminum extraction greatly increased. Aluminum extractions were accordingly made in the form of sodium aluminate from the deashing solutions of coals, which could be advantageous for sandy alumina production. Full article
(This article belongs to the Section Materials Chemistry)
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