Observation of stacking engineered magnetic phase transitions within moiré supercells of twisted van der Waals magnets.

Recent demonstrations of moiré magnetism, featuring exotic phases with noncollinear spin order in the twisted van der Waals (vdW) magnet chromium triiodide CrI3, have highlighted the potential of twist engineering of magnetic (vdW) materials. However, the local magnetic interactions, spin dynamics, and magnetic phase transitions within and across individual moiré supercells remain elusive. Taking advantage of a scanning single-spin magnetometry platform, here we report observation of two distinct magnetic phase transitions with separate critical temperatures within a moiré supercell of small-angle twisted double trilayer CrI3. By measuring temperature-dependent spin fluctuations at the coexisting ferromagnetic and antiferromagnetic regions in twisted CrI3, we explicitly show that the Curie temperature of the ferromagnetic state is higher than the Néel temperature of the antiferromagnetic one by ~10 K. Our mean-field calculations attribute such a spatial and thermodynamic phase separation to the stacking order modulated interlayer exchange coupling at the twisted interface of moiré superlattices.

Arginine Biosynthesis Mediates Wulingzhi Extract Resistance to Busulfan-Induced Male Reproductive Toxicity.

Busulfan, an indispensable medicine in cancer treatment, can cause serious reproductive system damage to males as a side effect of its otherwise excellent therapeutic results. Its widespread use has also caused its accumulation in the environment and subsequent ecotoxicology effects. As a Chinese medicine, Wulingzhi (WLZ) has the effects of promoting blood circulation and improving female reproductive function. However, the potential effects of WLZ in male reproduction and in counteracting busulfan-induced testis damage, as well as its probable mechanisms, are still ambiguous. In this study, busulfan was introduced in a mouse model to evaluate its production of the testicular damage. The components of different WLZ extracts were compared using an untargeted metabolome to select extracts with greater efficacy, which were further confirmed in vivo. Here, we demonstrate abnormal spermatogenesis and low sperm quality in busulfan-injured testes. The WLZ extracts showed a strong potential to rehabilitate the male reproductive system; this effect was more prominent in room-temperature extracts. Additionally, both water and ethanol WLZ extracts at room temperature alleviated various busulfan-induced adverse effects. In particular, WLZ recovered spermatogenesis, re-activated arginine biosynthesis, and alleviated the increased oxidative stress and inflammation in the testis, ultimately reversing the busulfan-induced testicular injury. Collectively, these results suggest a promising approach to protecting the male reproductive system from busulfan-induced adverse side effects, as well as those of other similar anti-cancer drugs.

Corrigendum: Fat fraction quantification with MRI estimates tumor proliferation of hepatocellular carcinoma.

[This corrects the article DOI: 10.3389/fonc.2024.1367907.].

Molecular Changes Implicate Angiogenesis and Arterial Remodeling in Systemic Sclerosis-Associated and Idiopathic Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension (PH) is a common complication of systemic sclerosis (SSc) and a leading cause of mortality among patients with this disease. PH can also occur as an idiopathic condition (idiopathic pulmonary arterial hypertension). Investigation of transcriptomic alterations in vascular populations is critical to elucidating cellular mechanisms underlying pathobiology of SSc-associated and idiopathic PH. METHODS: We analyzed single-cell RNA sequencing profiles of endothelial and perivascular mesenchymal populations from explanted lung tissue of patients with SSc-associated PH (n=16), idiopathic pulmonary arterial hypertension (n=3), and healthy controls (n=15). Findings were validated by immunofluorescence staining of explanted human lung tissue. RESULTS: Three disease-associated endothelial populations emerged. Two angiogenic endothelial cell (EC) subtypes markedly expanded in SSc-associated PH lungs: tip ECs expressing canonical tip markers PGF and APLN and phalanx ECs expressing genes associated with vascular development, endothelial barrier integrity, and Notch signaling. Gene regulatory network analysis suggested enrichment of Smad1 and PPAR-γ (peroxisome proliferator-activated receptor-γ) regulon activities in these 2 populations, respectively. Mapping of potential ligand-receptor interactions highlighted Notch, apelin-APJ, and angiopoietin-Tie signaling pathways between angiogenic ECs and perivascular cells. Transitional cells, expressing both endothelial and pericyte/smooth muscle cell markers, provided evidence for the presence of endothelial-to-mesenchymal transition. Transcriptional programs associated with arterial endothelial dysfunction implicated VEGF-A (vascular endothelial growth factor-A), TGF-ß1, angiotensin, and TNFSF12/TWEAK in the injury/remodeling phenotype of PH arterial ECs. CONCLUSIONS: These data provide high-resolution insights into the complexity and plasticity of the pulmonary endothelium in SSc-associated PH and idiopathic pulmonary arterial hypertension and provide direct molecular insights into soluble mediators and transcription factors driving PH vasculopathy.

Sensing spin wave excitations by spin defects in few-layer-thick hexagonal boron nitride.

Optically active spin defects in wide bandgap semiconductors serve as a local sensor of multiple degrees of freedom in a variety of "hard" and "soft" condensed matter systems. Taking advantage of the recent progress on quantum sensing using van der Waals (vdW) quantum materials, here we report direct measurements of spin waves excited in magnetic insulator Y3Fe5O12 (YIG) by boron vacancy [Formula: see text] spin defects contained in few-layer-thick hexagonal boron nitride nanoflakes. We show that the ferromagnetic resonance and parametric spin excitations can be effectively detected by [Formula: see text] spin defects under various experimental conditions through optically detected magnetic resonance measurements. The off-resonant dipole interaction between YIG magnons and [Formula: see text] spin defects is mediated by multi-magnon scattering processes, which may find relevant applications in a range of emerging quantum sensing, computing, and metrology technologies. Our results also highlight the opportunities offered by quantum spin defects in layered two-dimensional vdW materials for investigating local spin dynamic behaviors in magnetic solid-state matters.

Single-cell transcriptomes and chromatin accessibility of endothelial cells unravel transcription factors associated with dysregulated angiogenesis in systemic sclerosis.

OBJECTIVES: Vasculopathy emerges early in systemic sclerosis (SSc) and links to endothelial cell (EC) injury and angiogenesis. Understanding EC transcriptomes and epigenomes is crucial for unravelling the mechanisms involved. METHODS: Transcriptomes and chromatin accessibility were assessed by single-cell RNA sequencing and single-nucleus transposase-accessible chromatin sequencing. Immunofluorescent staining of skin and proteomics assay were employed to confirm the altered SSc EC phenotypes. Gain-of-function assay was used to evaluate the effects of ETS transcription factors on human dermal ECs (hDECs). RESULTS: Both control and SSc ECs shared transcriptomic signatures of vascular linages (arterial, capillary and venous ECs) and lymphatic ECs. Arterial ECs in SSc showed reduced number and increased expression of genes associated with apoptosis. Two distinct EC subpopulations, tip and proliferating ECs, were markedly upregulated in SSc, indicating enhanced proangiogenic and proliferative activities. Molecular features of aberrant SSc-ECs were associated with disease pathogenesis and clinical traits of SSc, such as skin fibrosis and digital ulcers. Ligand-receptor analysis demonstrated altered intercellular networks of SSc EC subpopulations with perivascular and immune cells. Furthermore, the integration of open chromatin profiles with transcriptomic analysis suggested an increased accessibility of regulatory elements for ETS family transcription factors in SSc ECs. Overexpression of ETS genes in hDECs suggested ELK4, ERF and ETS1 may orchestrate arterial apoptosis and dysregulated angiogenesis in SSc. CONCLUSIONS: This study unveils transcriptional and chromatin alterations in driving endovascular dysregulation in SSc, proposing ELK4, ERF and ETS1 as novel targets in ECs for addressing vascular complications in the condition.

Fat fraction quantification with MRI estimates tumor proliferation of hepatocellular carcinoma.

Purpose: To assess the utility of fat fraction quantification using quantitative multi-echo Dixon for evaluating tumor proliferation and microvascular invasion (MVI) in hepatocellular carcinoma (HCC). Methods: A total of 66 patients with resection and histopathologic confirmed HCC were enrolled. Preoperative MRI with proton density fat fraction and R2* mapping was analyzed. Intratumoral and peritumoral regions were delineated with manually placed regions of interest at the maximum level of intratumoral fat. Correlation analysis explored the relationship between fat fraction and Ki67. The fat fraction and R2* were compared between high Ki67(>30%) and low Ki67 nodules, and between MVI negative and positive groups. Receiver operating characteristic (ROC) analysis was used for further analysis if statistically different. Results: The median fat fraction of tumor (tFF) was higher than peritumor liver (5.24% vs 3.51%, P=0.012). The tFF was negatively correlated with Ki67 (r=-0.306, P=0.012), and tFF of high Ki67 nodules was lower than that of low Ki67 nodules (2.10% vs 4.90%, P=0.001). The tFF was a good estimator for low proliferation nodules (AUC 0.747, cut-off 3.39%, sensitivity 0.778, specificity 0.692). There was no significant difference in tFF and R2* between MVI positive and negative nodules (3.00% vs 2.90%, P=0.784; 55.80s-1 vs 49.15s-1, P=0.227). Conclusion: We infer that intratumor fat can be identified in HCC and fat fraction quantification using quantitative multi-echo Dixon can distinguish low proliferative HCCs.

Single-cell epigenomic dysregulation of Systemic Sclerosis fibroblasts via CREB1/EGR1 axis in self-assembled human skin equivalents.

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin fibrosis, internal organ involvement and vascular dropout. We previously developed and phenotypically characterized an in vitro 3D skin-like tissue model of SSc, and now analyze the transcriptomic (scRNA-seq) and epigenetic (scATAC-seq) characteristics of this model at single-cell resolution. SSc 3D skin-like tissues were fabricated using autologous fibroblasts, macrophages, and plasma from SSc patients or healthy control (HC) donors. SSc tissues displayed increased dermal thickness and contractility, as well as increased α-SMA staining. Single-cell transcriptomic and epigenomic analyses identified keratinocytes, macrophages, and five populations of fibroblasts (labeled FB1 - 5). Notably, FB1 APOE-expressing fibroblasts were 12-fold enriched in SSc tissues and were characterized by high EGR1 motif accessibility. Pseudotime analysis suggests that FB1 fibroblasts differentiate from a TGF-ß1-responsive fibroblast population and ligand-receptor analysis indicates that the FB1 fibroblasts are active in macrophage crosstalk via soluble ligands including FGF2 and APP. These findings provide characterization of the 3D skin-like model at single cell resolution and establish that it recapitulates subsets of fibroblasts and macrophage phenotypes observed in skin biopsies.

Research on distributionally robust energy storage capacity allocation for output fluctuations in high permeability wind and solar distribution networks.

This paper presents a novel approach to addressing the challenges associated with energy storage capacity allocation in high-permeability wind and solar distribution networks. The proposed method is a two-phase distributed robust energy storage capacity allocation method, which aims to regulate the stochasticity and volatility of net energy output. Firstly, an energy storage capacity allocation model is established, which considers energy storage's investment and operation costs to minimize the total cost. Then, a two-stage distributed robust energy storage capacity allocation model is established with the confidence set of uncertainty probability distribution constrained by 1-norm and ∞-norm. Finally, a Column and Constraint Generation (C&CG) algorithm is used to solve the problem. The validity of the proposed energy storage capacity allocation model is confirmed by examining different wind and solar penetration levels. Furthermore, the model's superiority is demonstrated by comparing it with deterministic and robust models.

Long non-coding RNA H19X as a regulator of mononuclear cell adhesion to the endothelium in systemic sclerosis.

OBJECTIVE: To define the functional relevance of H19 X-linked co-expressed lncRNA (H19X) in endothelial cell (EC) activation as a key process in systemic sclerosis (SSc) vasculopathy. METHODS: H19X expression in SSc skin biopsies was analyzed from single cell RNA sequencing (scRNA-seq) data. Differential expression and pathway enrichment analysis between cells expressing (H19Xpos) and non expressing H19X (H19Xneg) cells was performed. H19X function was investigated in human dermal microvascular EC (HDMECs) by silencing. H19X and EC adhesion molecules levels were analyzed by RT-qPCR and Western Blot after stimulation with proinflammatory cytokines. Cytoskeletal rearrangements were analyzed by fluorescent staining. Endothelial adhesion was evaluated by co-culture of HDMECs and fluorescent labelled peripheral blood mononuclear cells (PBMCs). Shedding VCAM1 was evaluated by ELISA on HDMEC supernatant. RESULTS: scRNA-seq showed significant upregulation of H19X in SSc compared with healthy EC. In HDMEC, H19X was consistently induced by type I and II interferons. H19X knockdown lead to a significant decrease of the mRNA of several adhesion molecules. Particularly, vascular cell adhesion protein 1 (VCAM1) was significantly reduced at protein and mRNA levels. Co-expression analysis of the scRNA-seq data confirmed a higher expression of VCAM1 in (H19Xpos) EC. EC were also strongly associated with the 'cell adhesion molecule' pathway. Moreover, VCAM1 downstream pathway displayed less activation following H19X knockdown. Contractility of HDMEC, PBMC adhesion to HDMEC and VCAM1 shedding were also reduced following H19X knockdown. CONCLUSIONS: lncRNA H19X may contribute to EC activation in SSc vasculopathy, acting as a regulator of expression of adhesion molecules in EC.

Prediction of immunocyte infiltration and prognosis in postoperative hepatitis B virus-related hepatocellular carcinoma patients using magnetic resonance imaging.

Background: The immune microenvironment (IME) is closely associated with prognosis and therapeutic response of hepatitis B virus-related hepatocellular carcinoma (HBV-HCC). Multi-parametric magnetic resonance imaging (MRI) enables non-invasive assessment of IME and predicts prognosis in HBV-HCC. We aimed to construct an MRI prediction model of the immunocyte-infiltration subtypes and explore its prognostic significance. Methods: HBV-HCC patients at the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) with radical surgery (between 1 October and 30 December 2021) were prospectively enrolled. Patients with pathologically proven HCC (between 1 December 2013 and 30 October 2019) were retrospectively enrolled. Pearson correlation analysis was used to examine the relationship between the immunocyte-infiltration counts and MRI parameters. An MRI prediction model of immunocyte-infiltration subtypes was constructed in prospective cohort. Kaplan-Meier survival analysis was used to analyse its prognostic significance in the retrospective cohort. Results: Twenty-four patients were prospectively enrolled to construct the MRI prediction model. Eighty-nine patients were retrospectively enrolled to determine its prognostic significance. MRI parameters (relative enhancement, ratio of the apparent diffusion coefficient value of tumoral region to peritumoral region [rADC], T1 value) correlated significantly with the immunocyte-infiltration counts (leukocytes, T help cells, PD1+Tc cells, B lymphocytes). rADC differed significantly between high and low immunocyte-infiltration groups (1.47 ± 0.36 vs 1.09 ± 0.25, P = 0.009). The area under the curve of the MRI model was 0.787 (95% confidence interval 0.587-0.987). Based on the MRI model, the recurrence-free time was longer in the high immunocyte-infiltration group than in the low immunocyte-infiltration group (P = 0.026). Conclusions: MRI is a non-invasive method for assessing the IME and immunocyte-infiltration subtypes, and predicting prognosis in post-operative HBV-HCC patients.

Sast1-mediated manifold effects inhibit Plutella xylostella fertility.

BACKGROUND: Plutella xylostella (Linnaeus) is a destructive pest of cruciferous crops due to its strong reproductive capacity and extensive resistance to pesticides. Seminal fluid proteins (SFPs) are the main effective factors that determine the reproductive physiology and behaviour of both sexes. Although an increasing number of SFPs have been identified, the effects of astacins in SFPs on agricultural pests have not yet been reported. Here, we elucidated the mechanisms by which Sast1 (seminal astacin 1) regulates the fertility of Plutella xylostella (L.). RESULTS: PxSast1 was specifically expressed in the testis and accesssory gland. CRISPR/Cas9-induced PxSast1 knockout successfully constructed two homozygous mutant strains. Sast1 impaired the fertility of P. xylostella by separately regulating the reproductive capacity of males and females. Loss of PxSast1, on the one hand, significantly decreased the ability of males to mate and fertilize, mainly manifested as shortened mating duration, reduced mating competitiveness and decreased eupyrene sperm production; on the other hand, it significantly inhibited the expression of chorion genes in females, resulting in oogenesis deficits. Simultaneously, for mated females, the differentially expressed genes in signalling pathways related to oogenesis and chorion formation were significantly enriched after PxSast1 knockout. CONCLUSION: These analyses of the functions of PxSast1 as the regulator of spermatogenesis and oogenesis establish its importance in the fertility process of P. xylostella, as well as its potential as a promising target for genetic regulation-based pest control. © 2024 Society of Chemical Industry.

The Clinical Value of Metagenomic Next-Generation Sequencing in Pneumocystis jirovecii Pneumonia.

Background: The incidence of Pneumocystis jirovecii pneumonia (PJP) is increasing. Methods: 108 patients were analysed retrospectively at the Wuhan Union Hospital. The patients were classified into the PJP group or the P. jirovecii colonisation (PJC) group based on clinical diagnosis. Clinical data included demographics, laboratory examinations, treatment, and outcomes. Results: A notable difference in the fungal load was seen between two groups, with median reads of 3215.79 vs. 5.61 in two groups, respectively (P<0.001). The optimal threshold value for discriminating P. jirovecii infection between colonisation for mNGS was six, and serum (1,3)-ß-D-glucan (BDG) was 47.6 pg/mL. Besides, the positive detection rate of mNGS for co-pathogens in PJP patients was significantly higher than that of culture (88.16% vs. 22.37%, P<0.0001). Epstein-Barr virus and cytomegalovirus were the most common pathogens of co-infection in PJP patients. The antibiotic therapy in PJP patients was adjusted according to the mNGS results, of which seventeen (22.37%) were downgraded, 38 (50.0%) patients were upgraded, and 21 (27.63%) were unchanged. And almost all patients showed significant improvement in C-reactive protein. Conclusion: mNGS is a promising and valuable technique with good performance for differentiating P. jirovecii infection and colonisation, the detection of pathogens, and antibiotic treatment.

A developmental critical period for ocular dominance plasticity of binocular neurons in mouse superior colliculus.

Detecting visual features in the environment is crucial for animals' survival. The superior colliculus (SC) is implicated in motion detection and processing, whereas how the SC integrates visual inputs from the two eyes remains unclear. Using in vivo electrophysiology, we show that mouse SC contains many binocular neurons that display robust ocular dominance (OD) plasticity in a critical period during early development, which is similar to, but not dependent on, the primary visual cortex. NR2A- and NR2B-containing N-methyl-D-aspartate (NMDA) receptors play an essential role in the regulation of SC plasticity. Blocking NMDA receptors can largely prevent the impairment of predatory hunting caused by monocular deprivation, indicating that maintaining the binocularity of SC neurons is required for efficient hunting behavior. Together, our studies reveal the existence and function of OD plasticity in SC, which broadens our understanding of the development of subcortical visual circuitry relating to motion detection and predatory hunting.

Local Control of a Single Nitrogen-Vacancy Center by Nanoscale Engineered Magnetic Domain Wall Motion.

Effective control and readout of qubits form the technical foundation of next-generation, transformative quantum information sciences and technologies. The nitrogen-vacancy (NV) center, an intrinsic three-level spin system, is naturally relevant in this context due to its excellent quantum coherence, high fidelity of operations, and remarkable functionality over a broad range of experimental conditions. It is an active contender for the development and implementation of cutting-edge quantum technologies. Here, we report magnetic domain wall motion driven local control and measurements of the NV spin properties. By engineering the local magnetic field environment of an NV center via nanoscale reconfigurable domain wall motion, we show that NV photoluminescence, spin level energies, and coherence time can be reliably controlled and correlated to the magneto-transport response of a magnetic device. Our results highlight the electrically tunable dipole interaction between NV centers and nanoscale magnetic structures, providing an attractive platform to realize interactive information transfer between spin qubits and nonvolatile magnetic memory in hybrid quantum spintronic systems.

Highly sensitive and naked-eye detection of herpes simplex virus type 1 using LAMP- CRISPR/Cas12 diagnostic technology and gold nanoparticles.

Herpes simplex virus type 1 (HSV-1) Keratitis (HSK) is a highly prevalent eye disease worldwide, characterized by lifelong recurrent episodes and a major risk of leading to blindness. Detecting HSV-1 promptly and accurately can initiate a timely and appropriate therapeutic regimen, minimizing tissue damage and preventing vision impairment. Currently, PCR is the most reliable method for identifying HSV-1, but its utilization for point-of-care (POC) HSV-1 detection is limited due to the need for sophisticated equipment, particularly in areas with limited resources. Here, we propose a new method for on-site HSV detection by using LAMP-Cas12 diagnostic technology and gold nanoparticles. This technique possesses comparable sensitivity to qPCR, and its detection results could be easily read and interpreted without the need for complex equipment. In detecting HSV in clinical tear specimens, this strategy achieved a 93.9 % consistency in positive detection and a 100 % consistency in negative detection compared to qPCR. Our strategy innovates the technique of current HSV-1 detections and is expected to play a crucial role in POC diagnosis of HSK in the future.

Layer-Dependent Magnetism and Spin Fluctuations in Atomically Thin van der Waals Magnet CrPS4.

van der Waals (vdW) magnets, an emerging family of two-dimensional (2D) materials, have received tremendous attention due to their rich fundamental physics and significant potential for cutting-edge technological applications. In contrast to the conventional bulk counterparts, vdW magnets exhibit significant tunability of local material properties, such as stacking engineered interlayer coupling and layer-number dependent magnetic and electronic interactions, which promise to deliver previously unavailable merits to develop multifunctional microelectronic devices. As a further ingredient of this emerging topic, here we report nanoscale quantum sensing and imaging of the atomically thin vdW magnet chromium thiophosphate CrPS4, revealing its characteristic layer-dependent 2D static magnetism and dynamic spin fluctuations. We also show a large tunneling magnetoresistance in CrPS4-based spin filter vdW heterostructures. The excellent material stability and robust strategy against environmental degradation in combination with tailored magnetic properties highlight the potential of CrPS4 in developing state-of-the-art 2D spintronic devices for next-generation information technologies.

Assessing vaginal wall indexes in premenopausal versus postmenopausal women by transrectal linear array high-frequency probe.

OBJECTIVE: This study aimed to verify the feasibility of 2D measurement of full-layer thickness of vaginal wall and evaluation of its elasticity by shear wave elastic imaging using transrectal linear array high-frequency ultrasound and to investigate the differences of vaginal wall indexes in premenopausal versus postmenopausal women. METHOD: From September to November 2022, a total of 87 women in the Department of Gynecology, Nanjing First Hospital were examined by a sonographer using transrectal linear array high-frequency ultrasound, including 34 women of reproductive age and 53 postmenopausal women. The vagina was divided into upper, middle, and lower segments, and the full-layer thickness of each part was measured. Then shear wave elastography (SWE) was used, and the average value of Young's modulus was used to evaluate the degree of vaginal elasticity. RESULTS: Transrectal linear array high-frequency ultrasound can clearly display structures of vaginal wall; measurement of the full thickness of the vaginal wall and evaluation of the degree of vaginal elasticity were feasible. There was a statistically significant difference in the thickness of each part of the vaginal wall between pre- and postmenopausal women (P < 0.001); there was no significant difference in the vaginal Young's modulus of pre- and postmenopausal women (P = 0.073). CONCLUSION: Transrectal linear array high-frequency ultrasonography is a non-invasive and feasible method to measure vaginal wall thickness (VWT) and elasticity. There are significant differences in VWT between pre- and postmenopausal women.

Revealing intrinsic domains and fluctuations of moiré magnetism by a wide-field quantum microscope.

Moiré magnetism featured by stacking engineered atomic registry and lattice interactions has recently emerged as an appealing quantum state of matter at the forefront of condensed matter physics research. Nanoscale imaging of moiré magnets is highly desirable and serves as a prerequisite to investigate a broad range of intriguing physics underlying the interplay between topology, electronic correlations, and unconventional nanomagnetism. Here we report spin defect-based wide-field imaging of magnetic domains and spin fluctuations in twisted double trilayer (tDT) chromium triiodide CrI3. We explicitly show that intrinsic moiré domains of opposite magnetizations appear over arrays of moiré supercells in low-twist-angle tDT CrI3. In contrast, spin fluctuations measured in tDT CrI3 manifest little spatial variations on the same mesoscopic length scale due to the dominant driving force of intralayer exchange interaction. Our results enrich the current understanding of exotic magnetic phases sustained by moiré magnetism and highlight the opportunities provided by quantum spin sensors in probing microscopic spin related phenomena on two-dimensional flatland.

Quantum metric nonlinear Hall effect in a topological antiferromagnetic heterostructure.

Quantum geometry in condensed-matter physics has two components: the real part quantum metric and the imaginary part Berry curvature. Whereas the effects of Berry curvature have been observed through phenomena such as the quantum Hall effect in two-dimensional electron gases and the anomalous Hall effect (AHE) in ferromagnets, the quantum metric has rarely been explored. Here, we report a nonlinear Hall effect induced by the quantum metric dipole by interfacing even-layered MnBi2Te4 with black phosphorus. The quantum metric nonlinear Hall effect switches direction upon reversing the antiferromagnetic (AFM) spins and exhibits distinct scaling that is independent of the scattering time. Our results open the door to discovering quantum metric responses predicted theoretically and pave the way for applications that bridge nonlinear electronics with AFM spintronics.