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Macrophages are highly heterogeneous and exhibit a diversity of functions and phenotypes. They can be divided into pro‐inflammatory macrophages (M1) and anti‐inflammatory macrophages (M2). Diabetic wounds are characterized by a prolonged inflammatory phase and difficulty in healing due to the accumulation of pro‐inflammatory (M1) macrophages in the wound. Therefore, hydrogel dressings with macrophage heterogeneity regulation function hold great promise in promoting diabetic wound healing in clinical applications. However, the precise conversion of pro‐inflammatory M1 to anti‐inflammatory M2 macrophages by simple and biosafe approaches is still a great challenge. Here, an all‐natural hydrogel with the ability to regulate macrophage heterogeneity is developed to promote angiogenesis and diabetic wound healing. The protocatechuic aldehyde hybridized collagen‐based all‐natural hydrogel exhibits good bioadhesive and antibacterial properties as well as reactive oxygen species scavenging ability. More importantly, the hydrogel is able to convert M1 macrophages into M2 macrophages without the need for any additional ingredients or external intervention. This simple and safe immunomodulatory approach shows great application potential for shortening the inflammatory phase of diabetic wound repair and accelerating wound healing. An all‐natural hydrogel composed of small molecules pro‐catechol and collagen is developed to promote diabetic wound healing by modulating macrophage heterogeneity. The hydrogel exhibits good bioadhesive, antibacterial, and reactive oxygen species scavenging abilities. In vitro and in vivo experiments show that the hydrogel is able to promote the conversion of pro‐inflammatory (M1) macrophages to anti‐inflammatory (M2) macrophages and the expression of anti‐inflammatory factors.

The quantum anomalous Hall (QAH) effect is a consequence of non-zero Berry curvature in momentum space. The QAH insulator harbours dissipation-free chiral edge states in the absence of an external magnetic field. However, the topological Hall (TH) effect, a hallmark of chiral spin textures, is a consequence of real-space Berry curvature. Here, by inserting a topological insulator (TI) layer between two magnetic TI layers, we realized the concurrence of the TH effect and the QAH effect through electric-field gating. The TH effect is probed by bulk carriers, whereas the QAH effect is characterized by chiral edge states. The appearance of the TH effect in the QAH insulating regime is a consequence of chiral magnetic domain walls that result from the gate-induced Dzyaloshinskii–Moriya interaction and occurs during the magnetization reversal process in the magnetic TI sandwich samples. The coexistence of chiral edge states and chiral spin textures provides a platform for proof-of-concept dissipationless spin-textured spintronic applications. The coexistence of chiral edge states and chiral spin textures in magnetic topological insulator sandwiches provides a platform for proof-of-concept dissipationless spin-textured spintronic applications.

To increase the reliability and success rate of drug discovery, efforts have been made to increase the C( sp 3 ) fraction and avoid flat molecules. sp 3 -Rich enantiopure amines are most frequently encountered as chiral auxiliaries, synthetic intermediates for pharmaceutical agents and bioactive natural products. Streamlined construction of chiral aliphatic amines has long been regarded as a paramount challenge. Mainstream approaches, including hydrogenation of enamines and imines, C–H amination, and alkylation of imines, were applied for the synthesis of chiral amines with circumscribed skeleton structures; typically, the chiral carbon centre was adjacent to an auxiliary aryl or ester group. Herein, we report a mild and general nickel-catalysed asymmetric reductive hydroalkylation to effectively convert enamides and enecarbamates into drug-like α-branched chiral amines and derivatives. This reaction involves the regio- and stereoselective hydrometallation of an enamide or enecarbamate to generate a catalytic amount of enantioenriched alkylnickel intermediate, followed by C–C bond formation via alkyl electrophiles. Enantiopure aliphatic amines are frequently encountered as chiral auxiliaries and synthetic intermediates for bioactive compounds. Here, the authors report a mild nickel-catalysed asymmetric reductive hydroalkylation to convert enamides and enecarbamates into α-branched chiral amines and derivatives.

A quantum anomalous Hall (QAH) state is a two-dimensional topological insulating state that has a quantized Hall resistance of h /( Ce 2 ) and vanishing longitudinal resistance under zero magnetic field (where h is the Planck constant, e is the elementary charge, and the Chern number C is an integer) 1 , 2 . The QAH effect has been realized in magnetic topological insulators 3 – 9 and magic-angle twisted bilayer graphene 10 , 11 . However, the QAH effect at zero magnetic field has so far been realized only for C  = 1. Here we realize a well quantized QAH effect with tunable Chern number (up to C  = 5) in multilayer structures consisting of alternating magnetic and undoped topological insulator layers, fabricated using molecular beam epitaxy. The Chern number of these QAH insulators is determined by the number of undoped topological insulator layers in the multilayer structure. Moreover, we demonstrate that the Chern number of a given multilayer structure can be tuned by varying either the magnetic doping concentration in the magnetic topological insulator layers or the thickness of the interior magnetic topological insulator layer. We develop a theoretical model to explain our experimental observations and establish phase diagrams for QAH insulators with high, tunable Chern number. The realization of such insulators facilitates the application of dissipationless chiral edge currents in energy-efficient electronic devices, and opens up opportunities for developing multi-channel quantum computing and higher-capacity chiral circuit interconnects. The number of edge channels in quantum anomalous Hall insulators is controlled by varying either the magnetic dopant concentration or the interior spacer layer thickness, yielding Chern numbers up to 5.

A quantum anomalous Hall (QAH) insulator coupled to an s-wave superconductor is predicted to harbor chiral Majorana modes. A recent experiment interprets the half-quantized two-terminal conductance plateau as evidence for these modes in a millimeter-size QAH-niobium hybrid device. However, non-Majorana mechanisms can also generate similar signatures, especially in disordered samples. Here, we studied similar hybrid devices with a well-controlled and transparent interface between the superconductor and the QAH insulator. When the devices are in the QAH state with well-aligned magnetization, the two-terminal conductance is always half-quantized. Our experiment provides a comprehensive understanding of the superconducting proximity effect observed in QAH-superconductor hybrid devices and shows that the half-quantized conductance plateau is unlikely to be induced by chiral Majorana fermions in samples with a highly transparent interface.

The Berry phase picture provides important insights into the electronic properties of condensed matter systems. The intrinsic anomalous Hall (AH) effect can be understood as the consequence of non-zero Berry curvature in momentum space. Here, we fabricate TI/magnetic TI heterostructures and find that the sign of the AH effect in the magnetic TI layer can be changed from being positive to negative with increasing the thickness of the top TI layer. Our first-principles calculations show that the built-in electric fields at the TI/magnetic TI interface influence the band structure of the magnetic TI layer, and thus lead to a reconstruction of the Berry curvature in the heterostructure samples. Based on the interface-induced AH effect with a negative sign in TI/V-doped TI bilayer structures, we create an artificial “topological Hall effect”-like feature in the Hall trace of the V-doped TI/TI/Cr-doped TI sandwich heterostructures. Our study provides a new route to create the Berry curvature change in magnetic topological materials that may lead to potential technological applications. Berry curvature connects to exotic electronic phases hence it provides important insights to understand quantum materials. Here, the authors report sign change of the anomalous Hall effect resulted from Berry curvature change at the interface of a topological insulator/magnetic topological insulator heterostructure.

A topological insulator (TI) interfaced with an s -wave superconductor has been predicted to host topological superconductivity. Although the growth of epitaxial TI films on s -wave superconductors has been achieved by molecular-beam epitaxy, it remains an outstanding challenge for synthesizing atomically thin TI/superconductor heterostructures, which are critical for engineering the topological superconducting phase. Here we used molecular-beam epitaxy to grow Bi 2 Se 3 films with a controlled thickness on monolayer NbSe 2 and performed in situ angle-resolved photoemission spectroscopy and ex situ magnetotransport measurements on these heterostructures. We found that the emergence of Rashba-type bulk quantum-well bands and spin-non-degenerate surface states coincides with a marked suppression of the in-plane upper critical magnetic field of the superconductivity in Bi 2 Se 3 /monolayer NbSe 2 heterostructures. This is a signature of a crossover from Ising- to Rashba-type superconducting pairings, induced by altering the Bi 2 Se 3 film thickness. Our work opens a route for exploring a robust topological superconducting phase in TI/Ising superconductor heterostructures. Using molecular-beam epitaxy, we synthesize heterostructures of topological insulator Bi 2 Se 3 and the Ising superconductor monolayer NbSe 2 . By changing the Bi 2 Se 3 thickness, they demonstrate a crossover from Ising- to Rashba-type superconducting pairing.

Background Globally, common gynecological disorders such as Polycystic Ovary Syndrome (PCOS), endometriosis, uterine fibroids (non-malignant gynecological diseases), as well as cervical cancer, uterine cancer, and ovarian cancer (gynecological cancers), profoundly impact women’s physical and mental health. The burden of these diseases exhibits significant geographical disparities across different countries and regions, making a comprehensive and precise assessment of the global burden of gynecological diseases particularly crucial. Such an assessment will facilitate the development of region-specific prevention and treatment strategies, contributing to a more effective response to these health challenges. Methods Incidence, prevalence, mortality rates, and Disability-Adjusted Life Years (DALYs) data for the aforementioned gynecological conditions were obtained from the 2021 Global Burden of Disease (GBD) study and analyzed by age, location, and year. The burden associated with gynecological diseases was analyzed based on the Socio-demographic Index (SDI) and attributable risk factors. The Estimated Annual Percentage Change (EAPC) and its 95% Confidence Interval (CI) were used to assess temporal trends in burden. Results In 2021, uterine fibroids were the leading non-malignant gynecological condition contributing to the highest Age-Standardized Incidence Rate (ASIR) and Age-Standardized Prevalence Rate (ASPR), with rates of 250.93 and 2841.07 per 100,000, respectively. Cervical cancer was the main contributor to the Age-Standardized Mortality Rate (ASMR) and Age-Standardized Disability Rate (ASDR) among the eight selected gynecological diseases, with rates of 6.62 and 226.28 per 100,000, respectively. From 1990 to 2021, the ASIR and ASPR for non-malignant gynecological conditions, such as PCOS and uterine fibroids, increased, while the ASDR for PCOS also rose. Among gynecological cancers, the ASIR for uterine cancer increased, while the ASPR for cervical cancer rose. However, the ASIR for cervical and ovarian cancers decreased, along with reductions in the ASMR and ASDR for these cancers and uterine cancer. There were notable regional disparities based on the SDI. In 2021, lower SDI regions had higher incidence, prevalence, mortality rates, and DALYs for endometriosis and cervical cancer, whereas higher SDI regions saw higher rates for PCOS, uterine fibroids, ovarian cancer, and uterine cancer, with more significant mortality and DALYs for ovarian and uterine cancers. The age distribution of these conditions varied. Non-malignant gynecological conditions, such as PCOS and uterine fibroids, primarily affect women aged 30–34 and 40–69. Endometriosis is most common in women aged 20–34, particularly between 25 and 29. Gynecological cancers, including cervical, uterine, and ovarian cancers, predominantly affect women over 35, especially between 40 and 69, with cervical cancer peaking at ages 50–54. Regarding attributable risk factors globally, 1% of cervical cancer deaths were linked to unsafe sexual behaviors, while a high Body Mass Index(BMI) contributed to 0.09% of ovarian cancer deaths and 0.34% of uterine cancer deaths. Conclusion The global burden of these six gynecological conditions poses a significant public health challenge. There is an urgent need for international collaboration to advance the development of age and regionally differentiated management strategies for gynecological diseases, including the development of effective diagnostic screening tools and the implementation of high-quality, targeted prevention and treatment strategies.

The discovery of Weyl semimetals (WSMs) has fueled tremendous interest in condensed matter physics. The realization of WSMs requires the breaking of either inversion symmetry (IS) or time-reversal symmetry (TRS). WSMs can be categorized into type-I and type-II WSMs, which are characterized by untilted and strongly tilted Weyl cones, respectively. Type-I WSMs with breaking of either IS or TRS and type-II WSMs with solely broken IS have been realized experimentally, but a TRS-breaking type-II WSM still remains elusive. In this article, we report transport evidence for a TRS-breaking type-II WSM observed in the intrinsic antiferromagnetic topological insulatorMn(Bi1−xSbx)2Te4under magnetic fields. This state is manifested by the electronic structure transition caused by the spin-flop transition. The transition results in an intrinsic anomalous Hall effect and negativec-axis longitudinal magnetoresistance attributable to the chiral anomaly in the ferromagnetic phases of lightly hole-doped samples. Our results establish a promising platform for exploring the underlying physics of the long-sought, ideal TRS-breaking type-II WSM.

One-dimensional chiral interface channels can be created at the boundary of two quantum anomalous Hall (QAH) insulators with different Chern numbers. Such a QAH junction may function as a chiral edge current distributer at zero magnetic field, but its realization remains challenging. Here, by employing an in-situ mechanical mask, we use molecular beam epitaxy to synthesize QAH insulator junctions, in which two QAH insulators with different Chern numbers are connected along a one-dimensional junction. For the junction between Chern numbers of 1 and −1, we observe quantized transport and demonstrate the appearance of the two parallel propagating chiral interface channels along the magnetic domain wall at zero magnetic field. For the junction between Chern numbers of 1 and 2, our quantized transport shows that a single chiral interface channel appears at the interface. Our work lays the foundation for the development of QAH insulator-based electronic and spintronic devices and topological chiral networks. Quantum anomalous Hall junctions show great promise for advancing next-generation electronic circuits. Here, the authors demonstrate a scalable method for synthesizing heterostructures of magnetic topological insulators with regions of distinct Chern numbers and characterize the chiral interface modes that emerge at the interface.