The Royal Society of Chemistry最新文献

Magnetism has been a central theme of research in chemistry, physics, and materials science, with chemical composition and bonding playing key roles in determining magnetic behavior. Altermagnets are a newly identified class of magnetic materials that combine features of conventional ferromagnets and antiferromagnets, arising from specific symmetry and electronic structure motifs. In this review, we present a chemistry-driven viewpoint on altermagnetism, highlighting how crystal chemistry, bonding, and electronic structure enable this unconventional magnetic order. We begin by introducing the fundamental concepts required to understand altermagnets, with an emphasis on symmetry considerations, orbital character, and electronic structure signatures. We then survey the diverse material families in which altermagnetism has been identified, including pnictides, oxides, and metal-organic and covalent-organic frameworks, drawing attention to coordination environments and structure-property relationships that favor altermagnetic order. We subsequently present experimental approaches which are useful for the synthesis and characterization of altermagnetic materials. We examine ab initio materials discovery as a promising strategy for identifying new altermagnets, emphasizing how chemical constraints, such as symmetry and bonding, can guide computational searches. Other than their intrinsic importance, altermagnets provide interesting possibilities for technology. For this reason, we highlight possible applications that may be enabled through altermagnetic materials, along with their coupling with existing orders such as ferroelectricity and superconductivity. In conclusion, we point out some challenges and prospects, where chemically-based design guidelines can play an important role towards advancing altermagnetism research. In summary, this review offers an account of recent developments in altermagnetism, from basic concepts to the current state-of-the-art.

Cholestatic liver injury (CLI) is a progressive liver disorder characterized by impaired bile acid (BA) synthesis, transport, and excretion. This dysfunction leads to the intrahepatic accumulation of toxic BAs, which in turn triggers hepatic oxidative stress, inflammation, and subsequent fibrogenesis. Through enterohepatic circulation, the gut and liver form an integrated gut-liver axis that regulates BA metabolism. Gut microbiota and nuclear receptor farnesoid X receptor (FXR) are tightly involved in modulating this axis and play a critical role in maintaining BA homeostasis. Disruption of the gut-liver axis under cholestatic conditions contributes to gut dysbiosis, BA imbalance, impaired intestinal barrier integrity, hepatic inflammation, and fibrotic progression. Flavonoids, a major class of polyphenols present in various foods, possess microbial-dependent biotransformation and gut enrichment characteristics. Through coordinated modulation of gut microbiota, BA metabolism, and host signaling pathways, flavonoids display promising protective effects against multiple pathological outcomes associated with CLI. This review summarizes the pathological mechanisms of CLI and the molecular interactions through which dietary flavonoids modulate the gut microbiota-BA-FXR axis. It further discusses the dietary exposure, bioavailability, and translational relevance of flavonoids by comparing human dietary intake and systemic exposure with preclinical doses, while evaluating safety considerations and available clinical trial evidence. These insights provide a framework for evaluating the nutritional relevance of flavonoids and their potential as functional food ingredients for the prevention and management of CLI.

Background & aims: Whole egg (WE) is a good source of vitamin D and carotenoids but their effects on concurrent bioavailability from a co-consumed meal and differences by menopausal status, remain unclear. The aim of this study was to assess the effects of co-consuming WE with vitamin D and carotenoids-rich foods on their absorption in pre- and post-menopausal females. Methods: Nine pre-menopausal and 8 post-menopausal females completed 8 day trials (7 day controlled diet plus test day) separated by a 3-week washout. Participants consumed a cooked vegetable meal (primary source of vitamin D and carotenoids) with no egg (control) or 100 g of cooked WE (CWE). The meal provided 27 mg of carotenoids and 600 IU of vitamin D (mainly vitamin D₂ from fortified mushrooms) and eggs provided ∼0.5 mg of carotenoids and 80 IU of vitamin D₃. Blood was collected hourly for 10 hours and triacylglycerol-rich lipoprotein fractions (TRL) were isolated. Vitamin D metabolites and carotenoids in TRL were analyzed and the composite areas under the curve (AUC) were calculated. Results: Carotenoids AUC_{0-10 h} in TRL was significantly higher for the CWE than control in both pre-menopausal (104.2 ± 12.4 vs. 29.2 ± 12.4 ng mL^-1 × 10 h; p < 0.001) and post-menopausal females (62.7 ± 12.4 vs. 10.1 ± 12.4 ng mL^-1 × 10 h; p = 0.003). 25-hydroxyvitamin D₃ AUC_{0-10 h} in TRL was also higher with CWE than for the control in the pre-menopausal (1.34 ± 0.55 vs. 0.53 ± 0.55 ng mL^-1 × 10 h; p = 0.182) and significantly higher in the post-menopausal (2.70 ± 0.59 vs. 1.03 ± 0.59 ng mL^-1 × 10 h; p = 0.015) females. Vitamin D₂/D₃ and 25-hydroxyvitamin D₂ were undetectable. Menopausal status did not affect these postprandial responses. Conclusion: Co-consuming WE with a cooked vegetable meal effectively increased the absorption of carotenoids across life stages but not for vitamin D₂ from a cooked vegetable meal. Trial registration: NCT02679794.

Background & aims: Walnuts are nutrient-dense foods rich in bioactive compounds that may support mental health. However, evidence linking walnut consumption to mood regulation and to changes in urinary metabolites potentially associated with these effects in humans remains limited. This randomized crossover trial (RCT) aimed to evaluate the effects of an 8-week walnut (Juglans regia) intervention on mood states in young adults and to explore the potential mechanistic links through urinary serotonin metabolite (5-hydroxyindoleacetic acid, 5-HIAA), cortisol, and urolithins. Methods: In this 18-week open-label RCT, 31 healthy young adults (mean age 24.0 ± 4.2 years; 90.3% female) consumed 40 g per day of walnuts for 8 weeks (intervention) and followed a nut-free control period of equal length, separated by a 2-week washout. Mood states, perceived stress, well-being, and trait food cravings were assessed using validated questionnaires. Urinary concentrations of 5-HIAA and cortisol were quantified via ELISA and normalized to creatinine. Walnut-derived urolithins were determined in urine samples as biomarkers of intake by HPLC-QTOF-MS. Linear mixed-effects models were used to test differences in outcome variables between intervention and control conditions, and repeated-measures correlations were performed to assess within-individual associations between the outcome variables. Results: Compared to the control condition, the 8-week walnut intervention significantly reduced total mood disturbance scores (-4.85 points, p = 0.030). In addition, the walnut intervention significantly increased urinary 5-HIAA levels, with no changes in urinary cortisol. Increases in urinary 5-HIAA were significantly associated with reductions in fatigue (r = -0.392, p = 0.031) and total mood disturbance (r = -0.362, p = 0.049). Urinary levels of urolithins significantly increased during the intervention and were strongly correlated with concurrent changes in urinary 5-HIAA (r = 0.537 and r = 0.634, respectively). Conclusions: Daily walnut consumption improved total mood disturbance scores in young adults. These findings were accompanied by increased urinary 5-HIAA and urolithin levels. The concurrent changes in these urinary metabolites may reflect dietary, microbial, or peripheral metabolic responses to walnut consumption; however, mechanistic pathways warrant further investigation. These findings highlight the relevance of whole-food strategies in nutritional approaches to mental health.

Omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs), such as docosahexaenoic acid (DHA), are known for their positive health effects. To meet recommended intake levels, people commonly consume fish and microalgal oils as supplements, typically in the form of encapsulated triacylglycerols (TAGs). However, ingesting omega-3 LC-PUFAs dispersed in a food matrix may be beneficial, as this has been shown to improve digestion for other oil types. This study investigated the in vitro bioaccessibility and basolateral recovery of DHA in DHA-rich microalgae oil in various forms: bulk oil, encapsulated oil, powdered oil, and oil incorporated into a protein matrix. After adapting the INFOGEST protocol for lipid digestion, we assessed bioaccessibility after in vitro digestion using back titration and gas chromatography coupled to a flame ionization detector (GC-FID). We used a Caco-2 cell model, adapted to take into account the lipid adhesion to the plastic plate, to assess basolateral DHA recovery. Results showed that the digestion of encapsulated oil and bulk oil was similar (n = 3). Powdered oil showed higher bioaccessibility than bulk oil (47.0 ± 2.5% for powder and 9.5 ± 0.7% for bulk, n = 3). In the Caco-2 model, powdered oil showed higher basolateral recovery (4.8 ± 0.9%) than bulk oil (1.2 ± 0.2%), although the experimental model limits interpretation (n = 3). To evaluate matrix effects, we designed a vegan cheese-like matrix (VCM) using different proteins. DHA in the VCM was 38% more bioaccessible than in bulk oil (n = 3), and we observed no differences in basolateral recovery. Our findings highlight that food matrices play a critical role in DHA bioaccessibility and basolateral recovery, potentially indicating increased intestinal uptake. Rather than a one-size-fits-all approach, methodological choices, including digestion protocols, transport models, and quantification strategies, should be selected based on the specific research question.

Waxy hull-less barley (WHB), which is rich in β-glucan, reportedly exhibits immunomodulatory properties, but the underlying mechanism remains unclear. In this study, we investigated the immunological effects and underlying mechanism of a WHB-containing diet using DO 11.10 mice, in which the T-cell antigen (Ag)-specificity is largely restricted to ovalbumin to minimize WHB-specific adaptive immune responses. Fecal secretory IgA (SIgA) levels were consistently higher in the WHB intake group throughout the feeding period. In the ileum, expression of the IgA transporter polymeric immunoglobulin receptor (pIgR) and the retinoic acid-generating enzyme Raldh2 was significantly upregulated. WHB intake increased the ratio of MHCII⁺ CD86⁺ conventional dendritic cells (cDC) in the gut-associated lymphoid tissue (GALT) and peripheral blood, whereas no changes were observed in the spleen. IgA⁺ cells increased in peripheral blood but decreased in the GALT, whereas IgM⁺ and α4β7⁺ B cells were elevated in the GALT but reduced in the spleen. Microbiota analysis revealed increased α-diversity and a shift toward higher abundances of species in the butyrate-producing genera Oscillospira, accompanied by lower abundances of SMB53 and Allobaculum. Notably, the abundance of Allobaculum species was negatively correlated with fecal SIgA. These findings suggest that WHB consumption is associated with increased intestinal IgA secretion, activation of gut cDCs, upregulation of Raldh2 and pIgR, and coordinated changes in B-cell dynamics and the gut microbiota.

Developing thermally and mechanically robust insulation capable of maintaining performance under repeated vacuum cycling remains a critical challenge for aircraft, aerospace and cryogenic systems, where both thermal efficiency and structural integrity are required. This study focuses on overcoming the trade-off between low thermal conductivity and mechanical stability in polymer-based insulating materials that are prone to structural degradation under pressure fluctuations. Herein, we present a Kelvin lattice-reinforced foam that preserves intrinsic insulation properties of closed-cell polyurethane (PU). The lattice framework suppresses structural collapse during vacuum cycling, while the PU foam region preserves low thermal conductivity. As a result, the hybrid structure exhibits a peak stress enhancement of up to 25 times compared to pristine PU foam. Furthermore, after 50 vacuum cycles, the hybrid structure retains thermal conductivity to within 10%, and peak-to-plateau ratio by less than 20% from their initial values, demonstrating excellent retention of both thermal and mechanical properties. These results establish the PU-Kelvin hybrid as a viable insulation architecture for environments subject to repeated pressure fluctuations, including aircraft cabins, aerospace structures, and cryogenic applications.

Modern technological demands require metals to integrate structural and functional performance, yet conventional metallurgy remains constrained by intrinsic trade-offs among strength, electrical conductivity, and wear resistance. Neutron-star evolution offers a natural blueprint for overcoming this limitation: load-bearing nuclear matter forms continuous frameworks, while a permeating electron sea enables efficient charge transport, intrinsically decoupling mechanical support from transport functionality. Inspired by this principle, we designed a neutron-star-inspired metallic metamaterial that assigns load bearing to a tungsten framework and electrical transport to a silver network. Realized through sequential 3D printing and metal infiltration, the resulting Ag-W architecture delivers high strength (≈213 MPa), high electrical conductivity (>50% IACS), and ultra-low friction-reduced to ∼20% of conventional bulk metals, demonstrating an unusually favorable convergence of mechanical, electrical, and tribological performance that is difficult to achieve through composition-based alloying alone. Crucially, the performance gain goes beyond a simple composite effect, as evidenced by the ∼75% reduction in friction relative to non-neutron-star-like architected comparators. These results establish topology-guided metallic architectures as a promising complementary route for mitigating multi-property trade-offs.

Thermal instability remains a fundamental bottleneck in oxide-based resistive random-access memory (RRAM), where elevated operating temperatures invariably increase the high-resistance-state (HRS) leakage current and collapse the ON/OFF switching window, severely limiting reliable deployment. Here, an Au/AgHfO_3-x/Al₂O₃/FTO (fluorine-doped tin oxide) memristor is reported in which this paradigm is inverted. The HRS current anomalously decreases with increasing temperature, yielding a reversible ∼25-fold enhancement in the ON/OFF ratio from 300 K to 400 K. This counter-intuitive behavior originates from trap-controlled space charge-limited conduction (SCLC) at the chemically sharp 5 nm Al₂O₃ interlayer, where thermal energy depopulates shallow trap states, suppressing hopping-assisted leakage without disrupting filamentary conduction in the low-resistance state. The optimized heterostructure achieves a room-temperature ON/OFF ratio of 349 ± 53, endurance exceeding 10³ bipolar switching cycles, retention over 25 000 s, and ten discrete analog conductance states spanning six orders of magnitude. Device-derived conductance states are directly used as synaptic weights in software-level simulations of handwritten-digit classification and image denoising on the MNIST benchmark. The handwritten-digit classification achieves 97.74% accuracy via transfer learning without implementation in a physical crossbar array or its associated peripheral circuitry. These results establish interface-engineered trap control as a design principle for thermally self-correcting memristors, a class where elevated temperature enhances rather than degrades performance, with direct relevance to neuromorphic hardware in thermally demanding environments.

Correction for 'From the up-converting multimodal luminescent thermometer to ratiometric visual power density meter based on Er³⁺,Yb³⁺ emission' by Anam Javaid et al., Mater. Horiz., 2026, 13, 417-429, https://doi.org/10.1039/d5mh01369k.