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Background. 5-methylcytosine (m5C) is a major site of RNA methylation modification, and its abnormal modification is associated with the development of gastric cancer (GC). This study aimed to explore the value of m5C-related genes on the prognosis of GC patients through bioinformatics. Methods. First, m5C-related genes were obtained by nonnegative matrix factorization (NMF) analysis and differentially expressed analysis. The m5C-related model was established and validated in distinct datasets. Moreover, a differential analysis of risk scores according to clinical characteristics was performed. The enrichment analysis was carried out to elucidate the underlying molecular mechanisms. Furthermore, we calculated the differences in immunotherapy and chemotherapy sensitivity between the high- and low-risk groups. Finally, we validated the expression levels of identified model genes by quantitative real-time polymerase chain reaction (qRT-PCR). Results. A total of five m5C-related subtypes of GC patients in the TCGA database were identified. The m5C-related model was constructed based on APOD, ASCL2, MFAP2, and CREB3L3. Functional enrichment revealed that the m5C-related model might involve in the cell cycle and cell adhesion. Moreover, the high-risk group had a higher abundance of stromal and immune cells in malignant tumor tissues and a lower tumor purity than the low-risk group. The patients in the high-risk group were more sensitive to chemotherapy and had better sensitivity to CTLA4 inhibitors. Furthermore, qRT-PCR results from our specimens verified an over-expression of ASCL2, CREB3L3, and MFAP2 in the cancer cells compared with the normal cells. Conclusion. A total of five GC subtypes were identified, and a risk model was constructed based on m5C modification.

Fe, Cu dual metal single atom catalyst on commercial carbon black exhibited excellent oxygen reduction reaction performance.

The linear positive magnetoresistance (LPMR) is a widely observed phenomenon in topological materials, which is promising for potential applications on topological spintronics. However, its mechanism remains ambiguous yet, and the effect is thus uncontrollable. Here, we report a quantitative scaling model that correlates the LPMR with the Berry curvature, based on a ferromagnetic Weyl semimetal CoS 2 that bears the largest LPMR of over 500% at 2 K and 9 T, among known magnetic topological semimetals. In this system, masses of Weyl nodes existing near the Fermi level, revealed by theoretical calculations, serve as Berry-curvature monopoles and low-effective-mass carriers. Based on the Weyl picture, we propose a relation MR = e ℏ B Ω F , with B being the applied magnetic field and Ω F the average Berry curvature near the Fermi surface, and further introduce temperature factor to both MR/ B slope (MR per unit field) and anomalous Hall conductivity, which establishes the connection between the model and experimental measurements. A clear picture of the linearly slowing down of carriers, i.e., the LPMR effect, is demonstrated under the cooperation of the k -space Berry curvature and real-space magnetic field. Our study not only provides experimental evidence of Berry curvature–induced LPMR but also promotes the common understanding and functional designing of the large Berry-curvature MR in topological Dirac/Weyl systems for magnetic sensing or information storage.

Exploring and discovering various types of skyrmions has enriched the fundamental study and the active skyrmionics aiming at using skyrmions in spintronics due to the advantages of global stability as high-density magnetic information bit. The unique capability to introduce abundant spin structures, physical phenomena, and dynamics due to the interactions of 4f and 3d electrons push the rare-earth–transition metal (RE–TM) magnets into the research frontier again. Herein, the exotic magnetic domain configurations are discovered in traditional ThMn12-type RE–TM magnets. It is clearly demonstrated that the magnetic anisotropy alteration and magnetic coupling between the respective RE and TM sublattices are responsible for the abundant magnetic domain evolution. In particular, the field-free biskyrmions at room temperature and tunable spin texture transformation are successfully obtained via manipulating the in-plane magnetic anisotropy, which has broadened the physical mechanism and application exploration of manipulating ferrimagnetic order to generate topological spin structures in strategic rare-earth magnets.

SiCN thin film is one of the most attractive silicon-based materials due to its excellent electrical, mechanical and optical properties. In this study, SiCN thin films have been prepared by the radio frequency reactive magnetron sputtering method under different sputtering power, pressure, and substrate temperature. The microstructure, morphology, and the optical and field emission properties of SiCN thin films were performed. The results indicated that the high-quality SiCN thin films have been successfully prepared and it is proved that these properties can be tailored by the preparation conditions. A main near ultraviolet light emission line at around 370 nm in SiCN thin films makes it suitable for the development of optoelectronic devices. This study can provide novel guidance for the controlled preparation of high-quality SiCN thin films by magnetron sputtering.

The exploration of solid-state sodium superionic conductors with high sodium-ion conductivity, structural and electrochemical stability, and grand interface compatibility has become the key to the next-generation energy storage applications with high energy density and long cycling life. Among them, halide-based compounds exhibit great potential with the higher electronegativity of halogens than that of the sulfur element. In this work, combined with first-principles calculation and ab initio molecular dynamic simulation, the investigation of trivalent metal iodide-based Na superionic conductors

The efforts toward the experimental realization of spin-polarized transports in ideal materials or platforms, such as the magnetized graphene or various quantum Hall states, is a research hotspot in spintronics. Magnetic van der Waals materials open the door for exploring various physical phenomena, technologies, and integrating novel spintronic devices seamlessly within the 2D limit. Here, we demonstrate magnetic proximity effect in chromium trichloride (CrCl3)/bilayer graphene (BLG) heterostructures by low-temperature transport measurements. An effective exchange field induced in BLG has been demonstrated by the Zeeman spin Hall effect via nonlocal measurements. Furthermore, the exchange field modulates the quantum Hall ground state of BLG and thus favors the formation of a canted antiferromagnetic (CAF) phase in an external perpendicular magnetic field (B⊥). Asymmetric nonlocal magneto-transport behaviors are also observed at opposite B⊥ directions, due to the asymmetric modulation on the exchange field by external B⊥ directions. Our work suggests that the 2D magnetic van der Waals materials and graphene hybrid systems offer a unique platform for quantum Hall ferromagnetism physics.

All-solid-state sodium-ion batteries that utilize inorganic superionic conductors show great potential in energy storage applications. However, suitable Na superionic conductors with desirable high ionic conductivities and cross-linked diffusion networks are still in their infancy. In this work, we systematically studied the structural stabilities and Na ion transport mechanisms of the halide-based Na superionic conductors with different phase structures using first-principle calculations and data mining techniques. The iodide-based Na3YI6 with C2/m, Pm1, and P1c space groups possess fcc and hcp anion sublattices with stable octahedral Na occupations, differing from the reported fast-ion transport mechanism in the sulfide bcc anion ones with tetrahedral Na occupations. The Oct–Tet–Oct diffusion pathway and Na-site weighted phonon vibrational frequencies play crucial roles in the synergistic Na-ion transport capabilities, leading to Na ionic conductivities of 0.35, 0.18, and 9.1 × 10−3 mS cm−1 at room temperature and corresponding activation energies of 315.5, 351.1, and 454.0 meV for C2/m-Na3YI6, Pm1-Na3YI6, and P1c-Na3YI6, respectively. Restricted by the decisive diffusion triangle, P1c-Na3YI6 shows deficient Na-kinetic performance with one-dimensional blocked ion transport channels. The phase-structure-dependent ion transport networks involving Oct–Tet and Oct–Oct pathways broaden the diffusion channels and provide rational guidance for the experimental design of halide-based Na superionic conductors.

As an efficient converter between electromagnetic and mechanical energies, magnetostriction is an intriguing property for not only fundamental studies but also technological applications. However, the understanding of its microscopic origin remains challenging, which is critical for the development of magnetostriction materials. Here, the critical role of spin rotation in the giant magnetostriction of La(Fe,Al)13 is first revealed by the in-situ magnetic and temperature field of neutron powder diffraction. The giant magnetostriction originates from magnetic-field-driven spin moment rotation of canting structure, in which the sharp increase of ferromagnetic component causes the elongation of icosahedron inside of lattice. Furthermore, it is the first time to reveal the accurate canting antiferromagnetic structure in La(Fe,Al)13. The present study provides a new strategy, i.e., the spin rotation, for exploring new magnetostriction functional materials.

Two-dimensional (2D) magnetic materials exhibiting unique 2D-limit magnetism have attracted great attention due to their potential applications in ultrathin spintronic devices. These 2D magnetic materials and their heterostructures provide a unique platform for exploring physical effect and exotic phenomena. However, the degradation of most 2D magnetic materials at ambient conditions has so far hindered their characterization and integration into ultrathin devices. Furthermore, the effect of degradation on magnetoelectric transport properties, which is measured for the demonstration of exotic phenomena and device performance, has remained unexplored. Here, the first experimental investigation of the degradation of CrBr

Negative thermal expansion (NTE) plays an increasingly important role in the control of thermal expansion of materials. However, the discovery of strong NTE materials, which is rare, remains challe...

Self-healing materials, which can autonomously repair damages like living organisms, have undergone extensive development in the last decades. The bottleneck problems for their practical applications are long healing time, inferior mechanical strength, and aging sensitivity. Here, a new class of polymeric materials rationally grafted with oligo poly(ethylene glycol) is reported. The network based on the formation of multiple weak hydrogen bonds endows the elastomers with good comprehensive performances including high stretchability (725%), high strength (4.20 MPa), and fast self-healing process (40 s). Benefiting from characteristic multiple weak hydrogen bond interactions, the fractured elastomers maintain high healing efficiency even after aging for 192 h, showing an unusual aging insensitivity. A Sudoku structural device based on the developed elastomer shows shape memory effect, providing a new avenue for fabricating novel smart devices with complicated shapes.

A large linear negative thermal expansion (NTE) and expanded NTE temperature range (ΔTNTE) were obtained in magnetoelastic CrTe1-xSex (0 ≤ x ≤ 0.15) compounds. For CrTe compound, its thermal expansion coefficient of volume (αV) was calculated to be -28.8 ppm K-1 with the temperature ranging from 280 to 340 K. Substituting Te with Se atoms, the NTE behavior and magnetic properties can be well manipulated. With increasing Se in CrTe1-xSex (0 ≤ x ≤ 0.15) compounds, the ΔTNTE increases from 60 K (280-340 K for x = 0), to 80 K (240-320 K for x = 0.05), to 95 K (200-295 K for x = 0.1), and finally to 100 K (170-270 K for x = 0.15). Furthermore, a linear NTE remains independent of temperature for samples with x ≤ 0.1. The relationship between tunable NTE and magnetic properties was analyzed in detail, indicating that the NTE in CrTe1-xSex compounds originates from the magnetovolume effect (MVE).

Magnetic skyrmions are vortex-like spin textures with nontrivial spin topology and novel physical properties that show promise as an essential building block for novel spintronic applications. Skyrmions in synthetic antiferromagnets (SAF) have been proposed long-term to have many advantages than those in ferromagnetic materials, which suffer from fundamental limits for size and efficient manipulation. Thus, experimental realization of skyrmions in SAF is intensely pursued. Here we show the observation of zero-field stable magnetic skyrmions at room temperature in SAF [Co/Pd]/Ru/[Co/Pd] multilayers with Lorentz transmission electron microscope, where uncompensated moments of the SAF provide a medium for the skyrmion characterization. Isolated skyrmions and high-density skyrmions via magnetic field and electromagnetic coordinated methods have been observed, respectively. These created high-density skyrmions maintain at zero-field even when both the current and magnetic field are removed. The use of skyrmions in SAF would advance the process toward practical nonvolatile memories based on spin topology.

Numerous efforts in improving the hydrogen evolution reaction (HER) performance of transition metal dichalcogenides mostly focus on active sites exposing, vacancy engineering, and phase engineering...

Exploration for the new members of air-stable 2D antiferromagnetic magnets to widen the magnetic families has drawn great attention due to its potential applications in spintronic devices. In addition to seeking the intrinsic antiferromagnets, externally introducing antiferromagnetic ordering in existing 2D materials, such as structural regulation and phase engineering, may be a promising way to modulate antiferromagnetism in the 2D limit. In this work, the in situ nitrogen doping growth of ultrathin 2D Cr

Photo-modulated magnetism has become an emerging method for technological applications, such as magneto-optical devices. In this work, by introducing oxygen during rapid thermal annealing, NiFe/NiFe

Zero-thermal-expansion (ZTE) alloys, as dimensionally stable materials, are urgently required in many fields, particularly in highly advanced modern industries. In this study, high-performance ZTE with a negligible coefficient of thermal expansion a

Pt nanocatalysts play a critical role in direct methanol fuel cells (DMFCs) due to their appropriate adsorption/desorption energy, yet suffer from an unbalanced relationship between size-dependent activity and stability. Herein, mixed-dimensional Pt-Ni alloy polyhedral nanochains (Pt-Ni PNCs) with an ordered assembly of a nanopolyhedra-nanowire-nanopolyhedra architecture are fabricated as bifunctional electrocatalysts for DMFCs, effectively alleviating the size effect. The Pt-Ni PNCs exhibit 7.23 times higher mass activity for the anodic methanol oxidation reaction (MOR) than that of commercial Pt/C. In situ Fourier transform infrared spectroscopy and CO stripping measurements demonstrate the prominent stability of the Pt-Ni PNCs to resist CO poisoning. For the cathodic oxygen reduction reaction (ORR), a positive half-wave potential exceeding Pt/C is achieved by the Pt-Ni PNCs, and it can be well maintained for 10 000 cycles with negligible activity decay. The designed nanostructure can alleviate the agglomeration and dissolution problems of 0D small-sized Pt-Ni alloy nanocrystals and enrich surface atom steps and active facets of 1D chain-like nanostructures. This work provides a proposed strategy to improve the catalytic performance of Pt-based nanocatalysts by constructing novel interfacial relationships in mixed dimensions to alleviate the imbalance between catalytic activity and catalytic stability caused by size effects.

Exploring and controlling topological textures such as merons and skyrmions has attracted enormous interests from the perspective of fundamental research and spintronic applications. It has been predicted theoretically and proved experimentally that the lattice form of topological meron-skyrmion transformation can be realized with the requirement of external magnetic fields in chiral ferromagnets. However, such topological transition behavior has yet to be verified in other materials. Here, we report real-space observation of magnetic topology transformation between meron pairs and skyrmions in the localized domain wall of ferrimagnetic GdFeCo films without the need of magnetic fields. The topological transformation in the domain wall of ferrimagnet is introduced by temperature-induced spin reorientation transition (SRT) and the underlying mechanism is revealed by micromagnetic simulations. The convenient electric-controlling topology transformation and driving motion along the confined domain wall is further anticipated, which will enable advanced application in magnetic devices., Merons and Skyrmions, two topological spin-textures, have attracted a lot of interests due to their potential use in information storage. Here, the authors demonstrate the transformation of Meron pairs into Skyrmions without an applied magnetic field within domain walls of GdFeCo films.

Magnetic skyrmions are localized particle-like nontrivial swirls that are promising in building high-performance topological spintronic devices. The read-out functions in skyrmionic devices require the translation of magnetic skyrmions to electrical signals. Here, we report combined real-space magnetic imaging and anisotropic magnetoresistance studies on dipolar skyrmions. A single skyrmion chain and single skyrmion are observed using Lorentz transmission electron microscopy imaging. Meanwhile, the field, helicity, and skyrmion count dependence of anisotropic magnetoresistance of the Fe3Sn2 nanostructures are obtained simultaneously. Our results demonstrate that the anisotropic magnetoresistance of skyrmions is independent of the helicity and proportional to the skyrmion count. Our work could promote read-out operations in skyrmion-based spintronic devices.

Pt-based magnetic nanocatalysts are one of the most suitable candidates for electrocatalytic materials due to their high electrochemistry activity and retrievability. Unfortunately, the inferior durability prevents them from being scaled-up, limiting their commercial applications. Herein, an antiferromagnetic element Mn was introduced into PtCo nanostructured alloy to synthesize uniform Mn-PtCo truncated octahedral nanoparticles (TONPs) by one-pot method. Our results show that Mn can tune the blocking temperature of Mn-PtCo TONPs due to its antiferromagnetism. At low temperatures, Mn-PtCo TONPs are ferromagnetic, and the coercivity increases gradually with increasing Mn contents. At room temperature, the Mn-PtCo TONPs display superparamagnetic behavior, which is greatly helpful for industrial recycling. Mn doping can not only modify the electronic structure of PtCo TONPs but also enhance electrocatalytic performance for methanol oxidation reaction. The maximum specific activity of Mn-PtCo-3 reaches 8.1 A·m-2, 3.6 times of commercial Pt/C (2.2 A·m-2) and 1.4 times of PtCo TONPs (5.6 A·m-2), respectively. The mass activity decreases by only 30% after 2,000 cycles, while it is 45% and 99% (nearly inactive) for PtCo TONPs and commercial Pt/C catalysts, respectively.

The hexagonal MM'X alloys with giant magnetocaloric effects have become an important magnetic phase-transition alloy family. Among the studies on this family, various methods, including composition engineering, have been developed to tailor the magnetostructural transitions. In this study, we present an alternative scheme to tailor the magnetostructural transitions by applying high-temperature staged quenching and low-temperature cyclical ageing on the hexagonal MnCoGe-based alloys with unchanged compositions. The experimental results show that the martensitic transition temperature decreases due to the increasing number of thermal vacancies produced in the increasing annealing temperature, which indicates the martensitic transition is strongly dependent on the staged quenching from high temperatures that can tune the concentration of equilibrious thermal vacancies in alloys. As a result, a Curie temperature window is established, in which the coupling of magnetostructural transitions is successfully realized, showing tunable, large magnetocaloric effects. By further applying cyclical ageing at low-temperature region, the magnetostructural transitions and magnetocaloric effects can be tuned to higher temperatures again due to the release of the trapped thermal vacancies, showing a high tunability of the magnetostructural transitions. During these heat treatments, furthermore, the transitions are robust against the high temperatures up to 550 °C, with no decoupling of the structural and magnetic transitions. The present work provides an important, efficient scheme to tailor the magnetostructural transitions, multiple magnetic/structural phase states, and the related functional properties of hexagonal phase-transition alloy family, without changing the chemical composition of the materials.

Magnetic circular dichroism (MCD) and magnetic linear dichroism (MLD) have been investigated in a photoemission electron microscopy (PEEM) system excited by a deep ultra-violet (DUV) laser (with λ = 177.3 nm and hυ = 7.0 eV) for the first time. High resolution PEEM magnetic images (down to 43.2 nm) were directly obtained on a (001)-oriented magnetic FePt film surface with a circularly-polarized light under normal incidence. Furthermore, a stepped Cr seeding layer was applied to induce the formation of large-area epitaxial FePt films with (001) and (111) two orientations, where MLD with large asymmetry was observed in the transition area of two phases. It demonstrates that DUV laser can be a powerful source for high resolution magnetic imaging in the laboratory in absence of synchrotron facilities.

A spintronic device based on the spin-dependent Hall effect has attracted great interest because of its great potential applications in the multivalue storage and logic gate, which is a promising candidate to break the bottleneck of the information industry in the big data period. It is a technological challenge to implant spintronic devices into semiconductor integrated circuits. The anomalous Hall angle (θ), defined as the deviation of the electron flow from the current direction, is the key parameter to evaluate the capacity of Hall device compatibility. However, the bottleneck for the device is low θ (less than 5%) at room temperature (RT), making it difficult to directly complement with the semiconductor circuit which limits its potential application. Here, we report a simple perpendicular multilayered structure with θ up to 5.1% at RT. Wide working temperature (250-350 K) across RT for our samples will accelerate the potential applications in spintronic memory. A giant Hall angle at RT originates from the enhanced side-jump scattering at the atomic-scale-modified interfacial structure. The high θ at RT together with wide working temperature is practically significant and may provide the way for further 3D spintronic devices based on the spin-dependent Hall effect with ultrahigh storage density and ultralow power consumption.