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Search Results (266)

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12 pages, 1955 KB  
Article
A MOF-Mediated Strategy for In Situ Niobium Doping and Synthesis of High-Performance Single-Crystal Ni-Rich Cathodes
by Yinkun Gao, Huazhang Zhou, Shumin Liu, Shuyun Guan, Mingyang Liu, Peng Gao, Yongming Zhu and Xudong Li
Batteries 2025, 11(10), 368; https://doi.org/10.3390/batteries11100368 (registering DOI) - 5 Oct 2025
Abstract
The development of single-crystal Ni-rich layered cathode materials (SC-NCMs) is regarded as an effective strategy to address the mechanical failure issues commonly associated with polycrystalline counterparts. However, the industrial production of SC-NCM faces challenges such as lengthy processing steps, high manufacturing costs, and [...] Read more.
The development of single-crystal Ni-rich layered cathode materials (SC-NCMs) is regarded as an effective strategy to address the mechanical failure issues commonly associated with polycrystalline counterparts. However, the industrial production of SC-NCM faces challenges such as lengthy processing steps, high manufacturing costs, and inconsistent product quality. In this study, we innovatively propose a metal/organic framework (MOF)-mediated one-step synthesis strategy to achieve controllable structural preparation and in situ Nb5+ doping in SC-NCM. Using a Ni–Co–Mn-based MOF as both precursor and self-template, we precisely regulated the thermal treatment pathway to guide the nucleation and oriented growth of high-density SC-NCM particles. Simultaneously, Nb5+ was pre-anchored within the MOF framework, enabling atomic-level homogeneous doping into the transition metal layers during crystal growth. Exceptional electrochemical performance is revealed in the in situ Nb-doped SC-NCM, with an initial discharge capacity reaching 176 mAh/g at a 1C rate and a remarkable capacity retention of 86.36% maintained after 200 cycles. This study paves a versatile and innovative pathway for the design of high-stability, high-energy-density cathode materials via a MOF-mediated synthesis strategy, enabling precise manipulation of both morphology and chemical composition. Full article
38 pages, 9769 KB  
Review
Label-Free Cancer Detection Methods Based on Biophysical Cell Phenotypes
by Isabel Calejo, Ana Catarina Azevedo, Raquel L. Monteiro, Francisco Cruz and Raphaël F. Canadas
Bioengineering 2025, 12(10), 1045; https://doi.org/10.3390/bioengineering12101045 - 28 Sep 2025
Abstract
Progress in clinical diagnosis increasingly relies on innovative technologies and advanced disease biomarker detection methods. While cell labeling remains a well-established technique, label-free approaches offer significant advantages, including reduced workload, minimal sample damage, cost-effectiveness, and simplified chip integration. These approaches focus on the [...] Read more.
Progress in clinical diagnosis increasingly relies on innovative technologies and advanced disease biomarker detection methods. While cell labeling remains a well-established technique, label-free approaches offer significant advantages, including reduced workload, minimal sample damage, cost-effectiveness, and simplified chip integration. These approaches focus on the morpho-biophysical properties of cells, eliminating the need for labeling and thus reducing false results while enhancing data reliability and reproducibility. Current label-free methods span conventional and advanced technologies, including phase-contrast microscopy, holographic microscopy, varied cytometries, microfluidics, dynamic light scattering, atomic force microscopy, and electrical impedance spectroscopy. Their integration with artificial intelligence further enhances their utility, enabling rapid, non-invasive cell identification, dynamic cellular interaction monitoring, and electro-mechanical and morphological cue analysis, making them particularly valuable for cancer diagnostics, monitoring, and prognosis. This review compiles recent label-free cancer cell detection developments within clinical and biotechnological laboratory contexts, emphasizing biophysical alterations pertinent to liquid biopsy applications. It highlights interdisciplinary innovations that allow the characterization and potential identification of cancer cells without labeling. Furthermore, a comparative analysis addresses throughput, resolution, and detection capabilities, thereby guiding their effective deployment in biomedical research and clinical oncology settings. Full article
(This article belongs to the Special Issue Label-Free Cancer Detection)
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15 pages, 3399 KB  
Article
Predictive Value of Arterial Enhancement Fraction Derived from Dual-Layer Spectral Computed Tomography for Thyroid Microcarcinoma
by Yuwei Chen, Jiayi Yu, Liang Lv, Zuhua Song, Jie Huang, Bi Zhou, Xinghong Zou, Ya Zou and Dan Zhang
Diagnostics 2025, 15(19), 2427; https://doi.org/10.3390/diagnostics15192427 - 23 Sep 2025
Viewed by 87
Abstract
Background/Objectives: Accurately distinguishing malignancy in thyroid micronodules (≤10 mm) is crucial for clinical management, yet it is challenging due to the limitations of conventional ultrasonography-guided biopsy. This study aims to evaluate the predictive value of dual-layer spectral computed tomography (DSCT)-derived arterial enhancement fraction [...] Read more.
Background/Objectives: Accurately distinguishing malignancy in thyroid micronodules (≤10 mm) is crucial for clinical management, yet it is challenging due to the limitations of conventional ultrasonography-guided biopsy. This study aims to evaluate the predictive value of dual-layer spectral computed tomography (DSCT)-derived arterial enhancement fraction (AEF) in diagnosing thyroid microcarcinomas. Methods: In the study, 321 pathologically confirmed thyroid micronodules (benign = 131, malignant = 190) from Chongqing General Hospital underwent preoperative DSCT. Quantitative parameters of DSCT, including the normalized iodine concentration (NIC), normalized effective atomic number (NZeff), and slope of the spectral Hounsfield unit curve (λHU(40–100)), were assessed. Both single-energy CT (SECT)-derived AEF (AEFS) and DSCT-derived AEF (AEFD) were calculated. Conventional image features included microcalcifications and enhancement blurring. Correlation between AEFD and AEFS was determined using Spearman’s correlation coefficient. Diagnostic performance was evaluated by calculating the area under the curve (AUC) using receiver operating characteristic (ROC) analysis. Results: Malignant micronodules exhibited significantly lower AEFD (0.958 vs. 1.259, p < 0.001) and AEFS (0.964 vs. 1.436, p < 0.001) versus benign nodules. Arterial phase parameters—APλHU(40–100), APNIC, APNZeff—differed significantly between groups (all p < 0.001), whereas venous phase parameters (VPλHU(40–100), VPNIC, VPNZeff) showed no differences (all p > 0.05). Multivariate analysis revealed that λHU(40–100) as an independent predictor of malignancy, with an odds ratio (OR) of 0.600 (95% confidence interval (CI): 0.437–0.823; p = 0.002) and an AUC of 0.752 (95% CI: 0.698–0.806). A significant positive correlation was identified between AEFD and AEFS (r = 0.710; p < 0.001). For diagnosing malignancy, AEFD demonstrated superior overall performance (AUC: 0.794; sensitivity: 70.5%; specificity: 81.7%; accuracy: 75.1%) to AEFS (0.753; 71.1%; 74.0%; 72.3%), APλHU(40–100) (0.752; 68.9%; 75.6%; 71.7%), and calcification (0.573; 21.6%; 92.4%; 50.5%). Clinically, AEFD reduced the unnecessary biopsy rate to 18.3%, preventing 107 procedures in our cohort. Conclusions: AEFD and AEFS demonstrated strong correlation and comparable diagnostic performance in the evaluation of thyroid micronodules. Furthermore, AEFD showed favorable diagnostic efficacy compared to both spectral parameters and conventional imaging feature. More importantly, the application of AEFD significantly reduced unnecessary biopsy rates, highlighting its clinical value in optimizing patient management. Full article
(This article belongs to the Special Issue Thyroid Cancer: Types, Symptoms, Diagnosis and Management)
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5 pages, 1327 KB  
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Dual-Energy Computed Tomography (DECT) for Diagnosing Contrast-Induced Encephalopathy (CIE) Mimicking Intracranial Hemorrhage (ICH): A Rare Case
by Yuhong Shen and Tianhe Ye
Diagnostics 2025, 15(19), 2426; https://doi.org/10.3390/diagnostics15192426 - 23 Sep 2025
Viewed by 105
Abstract
Contrast-induced encephalopathy (CIE) is a rare complication after percutaneous coronary intervention (PCI) that mimics intracranial hemorrhage (ICH). Its computed tomography (CT) findings (cortical contrast enhancement, sulci effacement) overlap with cerebrovascular conditions (e.g., cerebral infarction, subarachnoid hemorrhage). Dual-energy CT (DECT) differentiates blood/calcification from iodinated [...] Read more.
Contrast-induced encephalopathy (CIE) is a rare complication after percutaneous coronary intervention (PCI) that mimics intracranial hemorrhage (ICH). Its computed tomography (CT) findings (cortical contrast enhancement, sulci effacement) overlap with cerebrovascular conditions (e.g., cerebral infarction, subarachnoid hemorrhage). Dual-energy CT (DECT) differentiates blood/calcification from iodinated contrast medium (CM) extravasation via material decomposition, contributing to the accurate diagnosis of CIE. We report a CIE case highlighting DECT’s value. A 74-year-old woman underwent PCI. 50 min post-PCI, she had moderate headache (Numeric Rating Scale 4), dizziness, non-projectile vomiting (no seizures); vital signs were stable, no focal deficits, mannitol ineffective. Non-contrast CT demonstrated a left parietal 75 Hounsfield unit (HU) high-attenuation lesion, indistinguishable from acute intracerebral hemorrhage. Conventional non-contrast CT revealed a high-attenuation lesion (75 HU) in the left parietal lobe—indistinguishable from ICH. DECT clarified the diagnosis: virtual non-contrast maps showed CM extravasation, iodine concentration maps confirmed focal CM accumulation, and effective atomic number maps improved lesion visualization. The patient’s headache resolved within 5 h; follow-up non-contrast CT at 24 h showed complete disappearance of the lesion. She resumed clopidogrel, discharged day 3 without sequelae. This case underscores DECT’s role in distinguishing CIE (transient CM, normal neuro exam) from ICH (persistent hemorrhage), guiding safe post-PCI antiplatelet therapy. Full article
(This article belongs to the Special Issue New Trends in Cardiovascular Imaging: 2nd Edition)
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44 pages, 1983 KB  
Review
Next-Generation Chemical Sensors: The Convergence of Nanomaterials, Advanced Characterization, and Real-World Applications
by Abniel Machín and Francisco Márquez
Chemosensors 2025, 13(9), 345; https://doi.org/10.3390/chemosensors13090345 - 8 Sep 2025
Viewed by 483
Abstract
Chemical sensors have undergone transformative advances in recent years, driven by the convergence of nanomaterials, advanced fabrication strategies, and state-of-the-art characterization methods. This review emphasizes recent developments, with particular attention to progress achieved over the past decade, and highlights the role of the [...] Read more.
Chemical sensors have undergone transformative advances in recent years, driven by the convergence of nanomaterials, advanced fabrication strategies, and state-of-the-art characterization methods. This review emphasizes recent developments, with particular attention to progress achieved over the past decade, and highlights the role of the United States as a major driver of global innovation in the field. Nanomaterials such as graphene derivatives, MXenes, carbon nanotubes, metal–organic frameworks (MOFs), and hybrid composites have enabled unprecedented analytical performance. Representative studies report detection limits down to the parts-per-billion (ppb) and even parts-per-trillion (ppt) level, with linear ranges typically spanning 10–500 ppb for volatile organic compounds (VOCs) and 0.1–100 μM for biomolecules. Response and recovery times are often below 10–30 s, while reproducibility frequently exceeds 90% across multiple sensing cycles. Stability has been demonstrated in platforms capable of continuous operation for weeks to months without significant drift. In parallel, additive manufacturing, device miniaturization, and flexible electronics have facilitated the integration of sensors into wearable, stretchable, and implantable platforms, extending their applications in healthcare diagnostics, environmental monitoring, food safety, and industrial process control. Advanced characterization techniques, including in situ Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS, Atomic Force Microscopy (AFM), and high-resolution electron microscopy, have elucidated interfacial charge-transfer mechanisms, guiding rational material design and improved selectivity. Despite these achievements, challenges remain in terms of scalability, reproducibility of nanomaterial synthesis, long-term stability, and regulatory validation. Data privacy and cybersecurity also emerge as critical issues for IoT-integrated sensing networks. Looking forward, promising future directions include the integration of artificial intelligence and machine learning for real-time data interpretation, the development of biodegradable and eco-friendly materials, and the convergence of multidisciplinary approaches to ensure robust, sustainable, and socially responsible sensing platforms. Overall, nanomaterial-enabled chemical sensors are poised to become indispensable tools for advancing public health, environmental sustainability, and industrial innovation, offering a pathway toward intelligent and adaptive sensing systems. Full article
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18 pages, 1005 KB  
Perspective
The Next Frontier in the Study of Noncovalent Bonding: Transition Metals
by Steve Scheiner
Molecules 2025, 30(17), 3643; https://doi.org/10.3390/molecules30173643 - 7 Sep 2025
Cited by 2 | Viewed by 899
Abstract
As work continues unabated in the study of noncovalent bonding, particularly σ-hole bonds, new challenges have emerged as the participation of transition metals in interactions of this sort is fast becoming appreciated. While there are certain similarities with the halogen, chalcogen, etc, bonds, [...] Read more.
As work continues unabated in the study of noncovalent bonding, particularly σ-hole bonds, new challenges have emerged as the participation of transition metals in interactions of this sort is fast becoming appreciated. While there are certain similarities with the halogen, chalcogen, etc, bonds, in which the main group elements participate, there are certain unique properties of these metal atoms that must be analyzed before a complete understanding can be attained. As one example, these atoms tend to act simultaneously as both electron donors and acceptors, a synergistic action that amplifies the overall bond strength. Ideas are expressed in this paper to hopefully guide future work in this exciting new arena. Full article
(This article belongs to the Section Physical Chemistry)
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20 pages, 2242 KB  
Review
The Use of Computational Approaches to Design Nanodelivery Systems
by Abedalrahman Abughalia, Mairead Flynn, Paul F. A. Clarke, Darren Fayne and Oliviero L. Gobbo
Nanomaterials 2025, 15(17), 1354; https://doi.org/10.3390/nano15171354 - 3 Sep 2025
Viewed by 803
Abstract
Nano-based drug delivery systems present a promising approach to improve the efficacy and safety of therapeutics by enabling targeted drug transport and controlled release. In parallel, computational approaches—particularly Molecular Dynamics (MD) simulations and Artificial Intelligence (AI)—have emerged as transformative tools to accelerate nanocarrier [...] Read more.
Nano-based drug delivery systems present a promising approach to improve the efficacy and safety of therapeutics by enabling targeted drug transport and controlled release. In parallel, computational approaches—particularly Molecular Dynamics (MD) simulations and Artificial Intelligence (AI)—have emerged as transformative tools to accelerate nanocarrier design and optimise their properties. MD simulations provide atomic-to-mesoscale insights into nanoparticle interactions with biological membranes, elucidating how factors such as surface charge density, ligand functionalisation and nanoparticle size affect cellular uptake and stability. Complementing MD simulations, AI-driven models accelerate the discovery of lipid-based nanoparticle formulations by analysing vast chemical datasets and predicting optimal structures for gene delivery and vaccine development. By harnessing these computational approaches, researchers can rapidly refine nanoparticle composition to improve biocompatibility, reduce toxicity and achieve more precise drug targeting. This review synthesises key advances in MD simulations and AI for two leading nanoparticle platforms (gold and lipid nanoparticles) and highlights their role in enhancing therapeutic performance. We evaluate how in silico models guide experimental validation, inform rational design strategies and ultimately streamline the transition from bench to bedside. Finally, we address key challenges such as data scarcity and complex in vivo dynamics and propose future directions for integrating computational insights into next generation nanodelivery systems. Full article
(This article belongs to the Section Theory and Simulation of Nanostructures)
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14 pages, 2531 KB  
Article
SEM-Based Approaches for the Identification and Quantification of Anhydrite
by Emmanuele Giordano, Arianna Paschetto, Emanuele Costa, Sabrina M. R. Bonetto, Pietro Mosca, Gianluca Frasca and Chiara Caselle
Appl. Sci. 2025, 15(17), 9584; https://doi.org/10.3390/app15179584 - 30 Aug 2025
Viewed by 417
Abstract
For investigating and modeling the swelling potential of anhydrite rocks, it is important to define a fast but accurate, reliable, and repeatable procedure for mineral identification and quantification of anhydrite mineral in rock samples. We propose a quantitative evaluation of the applicability of [...] Read more.
For investigating and modeling the swelling potential of anhydrite rocks, it is important to define a fast but accurate, reliable, and repeatable procedure for mineral identification and quantification of anhydrite mineral in rock samples. We propose a quantitative evaluation of the applicability of two different SEM-based approaches (namely, image analysis and the use of the O/S atomic ratio) for the identification and quantification of anhydrite in polished slices of rock. We compare the results obtained with the bulk densities of the samples and with the outcomes of thermogravimetric analyses, demonstrating high convergence between the different data. We eventually propose a critical comparison between the proposed approaches and the existing methods, overall providing a practical guide for the selection of the best analytical procedure for the quantification of anhydrite content in rocks and, consequently, for the correct estimation of swelling potential. Full article
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16 pages, 2947 KB  
Article
1,10-Phenanthroline-Iron Complex-Derived Fe-N-C Electrocatalysts: Enhanced Oxygen Reduction Activity and Stability Through Synthesis Tuning
by Carlos S. A. Vasconcellos, Nelson A. Galiote, Nadeem Khan, Enrique A. Paredes-Salazar, Maykon L. Souza, Kotaro Sasaki, Meng Li and Fabio H. B. Lima
Catalysts 2025, 15(9), 821; https://doi.org/10.3390/catal15090821 - 29 Aug 2025
Viewed by 709
Abstract
The development of electrocatalysts composed of earth-abundant elements is essential for advancing the commercial application of Proton Exchange Membrane Fuel Cells (PEMFC). Among these, single-atom electrocatalysts, such as Fe-N-C, show great promise for the oxygen reduction reaction (ORR). This study aims to improve [...] Read more.
The development of electrocatalysts composed of earth-abundant elements is essential for advancing the commercial application of Proton Exchange Membrane Fuel Cells (PEMFC). Among these, single-atom electrocatalysts, such as Fe-N-C, show great promise for the oxygen reduction reaction (ORR). This study aims to improve the ORR activity and stability of Fe-N-C electrocatalysts by fine-tuning the straightforward 1,10-phenanthroline-iron complexation synthesis method. Key parameters, including iron-to-phenanthroline ratio, carbon powder surface area, and pyrolysis temperature were systematically varied to evaluate their influence on the resulting electrocatalysts. The findings of this study revealed that the electrocatalysts synthesized with 1,10-phenanthroline (Phen) and high-surface-area Black Pearls (BP) possessed much better ORR activity than electrocatalysts prepared by using Vulcan carbon (lower surface area). Interestingly, electrocatalysts prepared with BP, but with a non-bidentate nitrogen-containing ligand molecule, such as imidazole, showed a much poorer activity, as the resulting material predominantly consisted of inactive structures, such as encapsulated iron nanoparticles and iron oxide, as evidenced by HR-TEM, EXAFS, and XRD. Therefore, the results suggest that only the synergistic combination of the bidentate ligand phenanthroline (Phen) and the high-surface-area carbon support (BP) favored the formation of ORR-active Fe-N-C single-atom species upon pyrolysis. The study also unveiled a significant enhancement in electrocatalyst stability during accelerated durability tests (and air storage) as the pyrolysis temperature was increased from 700 to 1300 °C, albeit at the expense of ORR activity, likely resulting from the generation of iron particles. Pyrolysis at 1050 °C yielded the electrocatalyst with the most favorable balance of activity and stability in rotating disk measurements, while maintaining moderate durability under PEM fuel cell operation. The insights obtained in this study may guide the development of more active efficient and durable electrocatalysts, synthesized via a simple method using earth-abundant elements, for application in PEMFC cathodes. Full article
(This article belongs to the Section Electrocatalysis)
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24 pages, 1850 KB  
Review
Pathophysiological Associations and Measurement Techniques of Red Blood Cell Deformability
by Minhui Liang, Dawei Ming, Jianwei Zhong, Choo Sheriel Shannon, William Rojas-Carabali, Kajal Agrawal, Ye Ai and Rupesh Agrawal
Biosensors 2025, 15(9), 566; https://doi.org/10.3390/bios15090566 - 28 Aug 2025
Cited by 1 | Viewed by 889
Abstract
Red blood cell (RBC), accounting for approximately 45% of total blood volume, are essential for oxygen delivery and carbon dioxide removal. Their unique biconcave morphology, high surface area-to-volume ratio, and remarkable deformability enable them to navigate microvessels narrower than their resting diameter, ensuring [...] Read more.
Red blood cell (RBC), accounting for approximately 45% of total blood volume, are essential for oxygen delivery and carbon dioxide removal. Their unique biconcave morphology, high surface area-to-volume ratio, and remarkable deformability enable them to navigate microvessels narrower than their resting diameter, ensuring efficient microcirculation. RBC deformability is primarily determined by membrane viscoelasticity, cytoplasmic viscosity, and cell geometry, all of which can be altered under various physiological and pathological conditions. Reduced deformability is a hallmark of numerous diseases, including sickle cell disease, malaria, diabetes mellitus, sepsis, ischemia–reperfusion injury, and storage lesions in transfused blood. As these mechanical changes often precede overt clinical symptoms, RBC deformability is increasingly recognized as a sensitive biomarker for disease diagnosis, prognosis, and treatment monitoring. Over the past decades, diverse techniques have been developed to measure RBC deformability. These include single-cell methods such as micropipette aspiration, optical tweezers, atomic force microscopy, magnetic twisting cytometry, and quantitative phase imaging; bulk approaches like blood viscometry, ektacytometry, filtration assays, and erythrocyte sedimentation rate; and emerging microfluidic platforms capable of high-throughput, physiologically relevant measurements. Each method captures distinct aspects of RBC mechanics, offering unique advantages and limitations. This review synthesizes current knowledge on the pathophysiological significance of RBC deformability and the methods for its measurement. We discuss disease contexts in which deformability is altered, outline mechanical models describing RBC viscoelasticity, and provide a comparative analysis of measurement techniques. Our aim is to guide the selection of appropriate approaches for research and clinical applications, and to highlight opportunities for developing robust, clinically translatable diagnostic tools. Full article
(This article belongs to the Special Issue Microfluidics for Sample Pretreatment)
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10 pages, 10211 KB  
Article
Orientation Relationships and Interface Structuring in Au-Seeded TiO2 Nanowires
by Adel M. Abuamr, Minghui Lin, Yushun Liu and Guozhen Zhu
Crystals 2025, 15(9), 766; https://doi.org/10.3390/cryst15090766 - 28 Aug 2025
Viewed by 407
Abstract
The Au–TiO2 interface plays a critical role in heterogeneous catalysis and nanostructure synthesis relevant to renewable energy applications. Using Au-seeded TiO2 nanowires as the model system, we observe that, in addition to the commonly reported orientation relationships (ORs) and atomically sharp [...] Read more.
The Au–TiO2 interface plays a critical role in heterogeneous catalysis and nanostructure synthesis relevant to renewable energy applications. Using Au-seeded TiO2 nanowires as the model system, we observe that, in addition to the commonly reported orientation relationships (ORs) and atomically sharp interfaces, Au–TiO2 interfaces can also exhibit ORs involving high-indexed planes, often accompanied by local disorder and atomic reconstructions involving multiple Ti-O monolayers. These interfacial rearrangements are promoted by high-temperature thermal treatment at 1000 °C during nanowire growth. The findings broaden our understanding of orientation relationships and interface structures in the Au–TiO2 system, offering valuable insights into interface-driven synthesis of oxide nanostructures and guiding future strategies for interface engineering in catalytic and electronic applications. Full article
(This article belongs to the Section Hybrid and Composite Crystalline Materials)
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16 pages, 4253 KB  
Article
Tailoring the Electronic and Structural Properties of Lead-Free A2ZrX6 “Defect” Perovskites: A DFT Study on A-Site Cation and Halogen Substitutions
by Christina Kolokytha, Demeter Tzeli and Nektarios N. Lathiotakis
Materials 2025, 18(17), 3976; https://doi.org/10.3390/ma18173976 - 25 Aug 2025
Viewed by 657
Abstract
Lead-free A2ZrX6 “defect” perovskites hold significant potential for many optoelectronic applications due to their stability and tunable properties. Extending a previous work, we present a first-principles density functional theory (DFT) study, utilizing PBE and HSE06 functionals, to systematically investigate the [...] Read more.
Lead-free A2ZrX6 “defect” perovskites hold significant potential for many optoelectronic applications due to their stability and tunable properties. Extending a previous work, we present a first-principles density functional theory (DFT) study, utilizing PBE and HSE06 functionals, to systematically investigate the impact of A-site cation and X-site halogen substitutions on the structural and electronic properties of these materials. We varied the A-site cation, considering ammonium, methylammonium, dimethylammonium, trimethylammonium, and phosphonium, and the X-site halogen, trying Cl, Br, and I. Our calculations reveal that both these substitutions significantly affect the band gap and the lattice parameters. Increasing A-site cation size generally enlarges the unit cell, while halogen electronegativity directly correlates with the band gap, yielding the lowest values for iodine-containing systems. We predict a broad range of band gaps (from ~4.79 eV for (PH4)2ZrCl6 down to ~2.11 eV for MA2ZrI6 using HSE06). The (PH4)2ZrX6 compounds maintain cubic crystal symmetry, unlike the triclinic of the ammonium-derived systems. Finally, our calculations show that the MA cation yields the smallest band gap among the ones studied, a result that is attributed to its size and the charges of the hydrogen atoms attached to nitrogen. Thus, our findings offer crucial theoretical insights into A2ZrX6 structure–property relationships, demonstrating how A-site cation and halogen tuning enables control over electronic and structural characteristics, thus guiding future experimental efforts for tailored lead-free perovskite design. Full article
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19 pages, 3937 KB  
Article
Exploring the Allosteric Pathways of Asciminib in the Dual Inhibition of BCR-ABL1
by Jie Ming, Hongwei Gao and Jiuyu Zhan
Biomolecules 2025, 15(9), 1214; https://doi.org/10.3390/biom15091214 - 22 Aug 2025
Viewed by 698
Abstract
The BCR-ABL1 fusion protein is a critical therapeutic target in Chronic Myeloid Leukemia (CML). Current monotherapy approaches involve types of inhibitors that can be categorized into ATP competitive inhibitors and allosteric inhibitors. However, resistance mutations in the tyrosine kinase domain of BCR-ABL1 have [...] Read more.
The BCR-ABL1 fusion protein is a critical therapeutic target in Chronic Myeloid Leukemia (CML). Current monotherapy approaches involve types of inhibitors that can be categorized into ATP competitive inhibitors and allosteric inhibitors. However, resistance mutations in the tyrosine kinase domain of BCR-ABL1 have limited the effectiveness of these drugs. Research indicates that dual inhibition of BCR-ABL1 by combining these two types of inhibitors effectively addresses the issue of drug resistance as there are no overlapping resistance mechanisms. However, the underlying reasons for the observed synergistic effects have not yet been thoroughly elucidated. In this study, we employed molecular dynamics simulation to observe the synergistic interactions of BCR-ABL1 by the allosteric inhibitor asciminib and ATP competitive inhibitors nilotinib and ponatinib. Our study reveals that when asciminib binds to BCR-ABL1, nilotinib and ponatinib exhibit more substantial binding stability compared to monotherapy. At the atomic level, we have elucidated the reasons for the enhanced binding affinity of nilotinib and ponatinib when using a co-inhibition therapy. Our study reveals the allosteric communication pathway between asciminib and ponatinib, providing more detailed insights into the effectiveness of combination therapy. These findings provide valuable insights into combination therapies, aiding in the rational use of medications and guiding the design of novel inhibitors. Full article
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31 pages, 8890 KB  
Review
Advancements in Non-Precious Metal Catalysts for High-Temperature Proton-Exchange Membrane Fuel Cells: A Comprehensive Review
by Naresh Narayanan, Balamurali Ravichandran, Indubala Emayavaramban, Huiyuan Liu and Huaneng Su
Catalysts 2025, 15(8), 775; https://doi.org/10.3390/catal15080775 - 14 Aug 2025
Viewed by 1311
Abstract
High-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) represent a promising clean energy technology and are valued for their fuel flexibility and simplified balance of plant. Their commercialization, however, is critically hindered by the prohibitive cost and resource scarcity of platinum-group metal (PGM) catalysts. The [...] Read more.
High-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) represent a promising clean energy technology and are valued for their fuel flexibility and simplified balance of plant. Their commercialization, however, is critically hindered by the prohibitive cost and resource scarcity of platinum-group metal (PGM) catalysts. The challenge is amplified in the phosphoric acid (PA) electrolyte of HT-PEMFCs, where the severe anion poisoning of PGM active sites necessitates impractically high catalyst loadings. This review addresses the urgent need for cost-effective alternatives by providing a comprehensive assessment of recent advancements in non-precious metal (NPM) catalysts for the oxygen reduction reaction (ORR) in HT-PEMFCs. It systematically explores synthesis strategies and structure–performance relationships for emerging catalyst classes, including transition metal compounds, metal–nitrogen–carbon (M-N-C) materials, and metal-free heteroatom-doped carbons. A significant focus is placed on M-N-C catalysts, particularly those with atomically dispersed Fe-Nx active sites, which have emerged as the most viable replacements for platinum due to their high intrinsic activity and notable tolerance to phosphate poisoning. This review critically analyzes key challenges that impede practical application, such as the trade-off between catalyst activity and stability, mass transport limitations in thick electrodes, and long-term degradation in the harsh PA environment. Finally, it outlines future research directions, emphasizing the need for a synergistic approach that integrates computational modeling with advanced operando characterization to guide the rational design of durable, high-performance catalysts and electrode architectures, thereby accelerating the path to commercial viability for HT-PEMFC technology. Full article
(This article belongs to the Section Electrocatalysis)
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13 pages, 1888 KB  
Article
Femtosecond-Laser Direct Writing of Double-Line and Tubular Depressed-Cladding Waveguides in Ultra-Low-Expansion Glass
by Yuhao Wu, Sixuan Guo, Guanghua Cheng, Feiran Wang, Xu Wang and Yunjie Zhang
Photonics 2025, 12(8), 797; https://doi.org/10.3390/photonics12080797 - 8 Aug 2025
Viewed by 1199
Abstract
Addressing the stability requirements of photonic integrated devices operating over wide temperature ranges, this work achieves controlled fabrication of femtosecond-laser direct-written Type II double-line waveguides and Type III depressed-cladding tubular waveguides within ultra-low-expansion LAS glass-ceramics. The light-guiding mechanisms were elucidated through finite element [...] Read more.
Addressing the stability requirements of photonic integrated devices operating over wide temperature ranges, this work achieves controlled fabrication of femtosecond-laser direct-written Type II double-line waveguides and Type III depressed-cladding tubular waveguides within ultra-low-expansion LAS glass-ceramics. The light-guiding mechanisms were elucidated through finite element modeling. The influences of laser writing parameters and waveguide geometric structures on guiding performance were systematically investigated. Experimental results demonstrate that the double-line waveguides exhibit optimal single-mode guiding performance at 30 μm spacing and 120 mW writing power. For the tubular depressed-cladding waveguides, both single-mode and multi-mode fields are attainable across a broad processing parameter window. Large-mode-area characteristics manifested in the 50 μm core waveguide, exhibiting an edge-shifted intensity profile for higher-order modes that generated a hollow beam, enabling applications in atom guidance and particle trapping. Full article
(This article belongs to the Special Issue Direct Ultrafast Laser Writing in Photonics and Optoelectronics)
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