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We propose a novel framework to describe geometric phases in quantum systems under non-adiabatic conditions by introducing the concept of a hidden geometric phase. Conventional geometric phases, such as the Berry phase, rely on adiabatic evolution, limiting their applicability in rapidly changing systems. Here, we remove this constraint by reinterpreting the geometric phase as arising from a dynamically evolving reference basis, independent of the external topological features. The hidden phase is revealed through transitionless quantum control techniques, ensuring pure geometric phase accumulation even in non-adiabatic regimes. Our method offers an exact solution to the neutron spin rotation phase in the Bitter–Dubbers experiment, aligning more closely with experimental data without depending on adiabatic approximations. This unexpected result broadens our understanding of the geometric phase observed in neutron spin rotation beyond the adiabatic conditions that are conventionally required.

Investigations using hot compression tests on a new high-strength weathering steel revealed specific deformation behaviors across different conditions. These tests were performed at temperatures ranging from 850 to 1050 °C and at strain rates from 0.01 to 5 s −1 . Results indicated that a decrease in the deformation temperature combined with an increase in strain rate notably enhanced both the maximum stress and strain achieved. Notably, above 900 °C and with strain rates below 0.1 s −1 , the flow stress of the material reached a steady state at certain strain levels. At a strain rate of 1 s −1 , irrespective of the temperature, the steel shows a continuous strain hardening behavior, achieving no stable flow stress state. Notably, when the true strain exceeds 0.8, an unusual increase in flow stress occurs, predominantly due to secondary work hardening effects. The microstructural changes in the deformed samples were examined using electron backscatter diffraction (EBSD), which helped elucidate the softening mechanisms inherent in this high-strength steel. Further, processing maps developed from true strains of 0.1–0.9, derived from the experimental flow stress data, suggest controlling the strain within 0.2–0.4 to minimize instability during hot working.

There is often a trade-off between mechanical properties (modulus and toughness) and dynamic self-healing. Here we report the design and synthesis of a polymer containing thermodynamically stable whilst kinetically labile coordination complex to address this conundrum. The Zn-Hbimcp (Hbimcp = 2,6-bis((imino)methyl)-4-chlorophenol) coordination bond used in this work has a relatively large association constant (2.2 × 10 11 ) but also undergoes fast and reversible intra- and inter-molecular ligand exchange processes. The as-prepared Zn(Hbimcp) 2 -PDMS polymer is highly stretchable (up to 2400% strain) with a high toughness of 29.3 MJ m −3 , and can autonomously self-heal at room temperature. Control experiments showed that the optimal combination of its bond strength and bond dynamics is responsible for the material’s mechanical toughness and self-healing property. This molecular design concept points out a promising direction for the preparation of self-healing polymers with excellent mechanical properties. We further show this type of polymer can be potentially used as energy absorbing material. There is often a trade-off between mechanical properties (modulus and toughness) and dynamic self-healing in materials. Here the authors design and synthesize a polymer containing thermodynamically stable whilst kinetically labile coordination complexes to address this conundrum.

Achieving a desirable combination of solid-like properties and fast self-healing is a great challenge due to slow diffusion dynamics. In this work, we describe a design concept that utilizes weak but abundant coordination bonds to achieve this objective. The designed PDMS polymer, crosslinked by abundant Zn(II)-carboxylate interactions, is very strong and rigid at room temperature. As the coordination equilibrium is sensitive to temperature, the mechanical strength of this polymer rapidly and reversibly changes upon heating or cooling. The soft–rigid switching ability σ, defined as G’ max /G’ min , can reach 8000 when ΔT = 100 °C. Based on these features, this polymer not only exhibits fast thermal-healing properties, but is also advantageous for various applications such as in orthopedic immobilization, conductive composites/adhesives, and 3D printing. Combining solid-like properties with fast self-healing is a great challenge due to slow diffusion dynamics. Here the authors demonstrate a rigid and healable material by using weak but abundant coordination bonds to crosslink a PDMS polymer.

Next-generation wearable electronics require enhanced mechanical robustness and device complexity. Besides previously reported softness and stretchability, desired merits for practical use include elasticity, solvent resistance, facile patternability and high charge carrier mobility. Here, we show a molecular design concept that simultaneously achieves all these targeted properties in both polymeric semiconductors and dielectrics, without compromising electrical performance. This is enabled by covalently-embedded in-situ rubber matrix (iRUM) formation through good mixing of iRUM precursors with polymer electronic materials, and finely-controlled composite film morphology built on azide crosslinking chemistry which leverages different reactivities with C–H and C=C bonds. The high covalent crosslinking density results in both superior elasticity and solvent resistance. When applied in stretchable transistors, the iRUM-semiconductor film retained its mobility after stretching to 100% strain, and exhibited record-high mobility retention of 1 cm 2 V −1 s −1 after 1000 stretching-releasing cycles at 50% strain. The cycling life was stably extended to 5000 cycles, five times longer than all reported semiconductors. Furthermore, we fabricated elastic transistors via consecutively photo-patterning of the dielectric and semiconducting layers, demonstrating the potential of solution-processed multilayer device manufacturing. The iRUM represents a molecule-level design approach towards robust skin-inspired electronics. Next-generation skin-inspired electronics require enhanced mechanical robustness and device complexity including elasticity, solvent resistance, and facile patternability. Here, the authors show a molecular design concept that simultaneously achieves all these requirements by covalently linking an in-situ formed rubber matrix with polymer electronic materials.

Gliomas are complex and heterogeneous brain tumors with poor prognosis. Glioma cells can communicate with their surroundings to create a tumor-permissive microenvironment. Exosomes represent a new means of intercellular communication by delivering various bioactive molecules, including proteins, lipids and nucleic acids, and participate in tumor initiation and progression. Noncoding RNAs (ncRNAs) including microRNA, long-noncoding RNA, and circular RNA, account for a large portion of human transcriptome and play important roles in various pathophysiological processes, especially in cancers. In addition, ncRNAs can be selectively packaged, secreted and transferred between cells in exosomes and modulate numerous hallmarks of glioma, such as proliferation, invasion, angiogenesis, immune-escape, and treatment resistance. Hence, the strategies of specifically targeting exosomal ncRNAs could be attractive therapeutic options. Exosomes are able to cross the blood brain barrier (BBB), and are readily accessible in nearly all types of human biofluids, which make them the promising biomarkers for gliomas. Additionally, given the biocompatibility of exosomes, they can be engineered to deliver therapeutic factors, such as RNA, proteins and drugs, to target cells for therapeutic applications. Here, we reviewed current research on the roles of exosomal ncRNAs in glioma progression. We also discussed their potential clinical applications as novel biomarkers and therapeutics.

Acoustic metasurfaces derive their characteristics from the interaction between acoustic waves and specifically designed materials. The field is driven by the desire to control acoustic wave propagation using compact devices and is governed by fundamental and physical principles that provide the design rules and the functionality of a wave. Acoustic metasurfaces have added value and unusual functionalities compared with their predecessor in materials science, namely, acoustic metamaterials. These rationally designed 2D materials of subwavelength thickness provide a new route for sound wave manipulation. In this Review, we delineate the fundamental physics of metasurfaces, describe their different concepts and design strategies, and discuss their functionalities for controllable reflection, transmission and extraordinary absorption. In particular, we outline the main designs of acoustic metasurfaces, including those based on coiling-up space, Helmholtz-resonator-like and membrane-type structures, and discuss their applications, such as beam focusing, asymmetrical transmission and self-bending beams. We conclude with an outlook of the future directions in this emerging field. Sound waves can be manipulated using structurally designed 2D materials of subwavelength thickness. This emerging field, namely, acoustic metasurfaces, is driven by the desire to control acoustic wave propagation using compact devices.

Objective This study aimed to investigate the effects of transforming growth factor β1 (TGF β1) and hepatocyte growth factor (HGF) on the expression of connective tissue growth factor (CTGF) in human atrial fibroblasts, and to explore the relationship of these factors in atrial fibrosis and atrial anatomical remodelling (AAR) of patients with atrial fibrillation (AF). Methods Fresh right auricular appendix tissue of 20 patients with rheumatic heart disease undergoing valve replacement surgery was collected during surgeries, 10 patients had sinus rhythm(SR), and 10 patients had chronic atrial fibrillation (CAF). Atrial fibroblasts were then cultured from the tissues with differential attachment technique and treated with either TGFβ1 (10 ng/mL) or HGF (100 ng/mL). CTGF mRNA levels were measured by RT‐PCR, and CTGF protein content was determined using immunofluorescence and Western blotting assays. Results CAF group had higher left atrial diameters (LADs) and higher CTGF mRNA expression in atrial fibroblasts compared with SR group. The CTGF protein content in CAF group was higher than that of SR group and positively correlated with LAD and AF duration. After CAF group was treated with TGFβ1, CTGF mRNA and protein expression were significantly down‐regulated, whereas when treated with HGF, expression was up‐regulated compared with SR group. Conclusions Increased CTGF expression was associated with enlarged LAD, atrial fibrosis and AAR in patients with AF. TGFβ1 and HGF regulate CTGF expression in human atrial fibroblasts with up‐regulation of mRNA and down‐regulation of protein, therefore, either promote or inhibit atrial fibrosis, which could be related to the incidence and persistence of AF.

Osteoarthritis (OA) is a progressive joint disease characterized by inflammation and cartilage destruction, and its progression is closely related to imbalances in the M1/M2 synovial macrophages. A two‐pronged strategy for the regulation of intracellular/extracellular nitric oxide (NO) and hydrogen protons for reprogramming M1/M2 synovial macrophages is proposed. The combination of carbonic anhydrase IX (CA9) siRNA and NO scavenger in “two‐in‐one” nanocarriers (NAHA‐CaP/siRNA nanoparticles) is developed for progressive OA therapy by scavenging NO and inhibiting CA9 expression in synovial macrophages. In vitro experiments demonstrate that these NPs can significantly scavenge intracellular NO similar to the levels as those in the normal group and downregulate the expression levels of CA9 mRNA (≈90%), thereby repolarizing the M1 macrophages into the M2 phenotype and increasing the expression levels of pro‐chondrogenic TGF‐β1 mRNA (≈1.3‐fold), and inhibiting chondrocyte apoptosis. Furthermore, in vivo experiments show that the NPs have great anti‐inflammation, cartilage protection and repair effects, thereby effectively alleviating OA progression in both monoiodoacetic acid‐induced early and late OA mouse models and a surgical destabilization of medial meniscus‐induced OA rat model. Therefore, the siCA9 and NO scavenger “two‐in‐one” delivery system is a potential and efficient strategy for progressive OA treatment. The carbonic anhydrase IX siRNA and nitric oxide (NO) scavenger in “two‐in‐one” nanocarriers is developed for progressive osteoarthritis (OA) therapy. A two‐pronged strategy is proposed for the regulation of intracellular/extracellular NO and hydrogen protons for reprogramming M1/M2 synovial macrophages, which holds promising application prospects for clinical translation of progressive OA treatment.