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1.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619536

RESUMO

Nanoscale spatially controlled modulation of the properties of ferroelectrics via artificial domain pattering is crucial to their emerging optoelectronics applications. New patterning strategies to achieve high precision and efficiency and to link the resultant domain structures with device functionalities are being sought. Here, we present an epitaxial heterostructure of SrRuO3/PbTiO3/SrRuO3, wherein the domain configuration is delicately determined by the charge screening conditions in the SrRuO3 layer and the substrate strains. Chemical etching of the top SrRuO3 layer leads to a transition from in-plane a domains to out-of-plane c domains, accompanied by a giant (>105) modification in the second harmonic generation response. The modulation effect, coupled with the plasmonic resonance effect from SrRuO3, enables a highly flexible design of nonlinear optical devices, as demonstrated by a simulated split-ring resonator metasurface. This domain patterning strategy may be extended to more thin-film ferroelectric systems with domain stabilities amenable to electrostatic boundary conditions.

2.
Aging (Albany NY) ; 16(5): 4563-4578, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38428406

RESUMO

BACKGROUND: Osteoarthritis (OA) is the most common degenerative joint disease worldwide. Further improving the current limited understanding of osteoarthritis has positive clinical value. METHODS: OA samples were collected from GEO database and endoplasmic reticulum related genes (ERRGs) were identified. The WGCNA network was further built to identify the crucial gene module. Based on the expression profiles of characteristic ERRGs, LASSO algorithm was used to select key factors according to the minimum λ value. Random forest (RF) algorithm was used to calculate the importance of ERRGs. Subsequently, overlapping genes based on LASSO and RF algorithms were identified as ERRGs-related diagnostic biomarkers. In addition, OA specimens were also collected and performed qRT-PCR quantitative analysis of selected ERRGs. RESULTS: We identified four ERRGs associated with OA risk assessment through machine learning methods, and verified the abnormal expressions of these screened markers in OA patients through in vitro experiments. The influence of selected markers on OA immune infiltration was also evaluated. CONCLUSIONS: Our results provide new evidence for the role of ER stress in the OA progression, as well as new markers and potential intervention targets for OA.


Assuntos
Algoritmos , Osteoartrite , Humanos , Retículo Endoplasmático , Aprendizado de Máquina , Osteoartrite/diagnóstico , Osteoartrite/genética , Biomarcadores
3.
Microbiol Spectr ; 12(3): e0136523, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315030

RESUMO

Hepatitis B virus (HBV) may directly infect human podocytes (HPCs). However, the mechanism of direct infection is unclear. We found that HPCs express sodium taurocholate cotransporting polypeptide (NTCP), a specific receptor for HBV entry into hepatocytes. Thus, we investigated whether NTCP mediates HBV infection and damage in HPCs and further clarified the specific mechanism. We constructed shRNA-NTCP1,2, shRNA-NC, WT-NTCP, and MUT-NTCP and transfected them into HPCs. HPCs were infected with HBV, and HBV infection markers were detected by enzyme-linked immunosorbent assay (ELISA) and real-time quantitative PCR (RT-qPCR). The functional changes in HPCs were detected by Transwell migration and scratch assays, apoptosis was evaluated by flow cytometry (FCM), and podocytoskeletal proteins (nephrin, CD2AP, and synaptopodin) were determined by western blotting (WB). Compared with the control HPCs, HPCs infected with HBV showed increased levels of HBV infection markers and apoptosis along with decreased podocytoskeletal protein expressions, cell vitality, proliferation, and migration. Compared with the HPCs infected with HBV, the HPCs transfected with HBV + shRNA-NTCP, and HBV + MUT-NTCP showed decreased levels of HBV infection markers and apoptosis along with increased podocytoskeletal protein expressions, cell vitality, proliferation, and migration; the opposite effects were observed in the HPCs transfected with HBV + WT-NTCP. Overall, the changes to NTCP affected the susceptibility of HPCs to HBV and modulated HPC damage and repair. NTCP can mediate direct HBV infection and damage human podocytes, and the NTCP 157-165 locus is the main site of HBV entry. The findings provide a new target and theoretical basis for HBV-associated glomerulonephritis. IMPORTANCE: This study identified for the first time that sodium taurocholate cotransporting polypeptide (NTCP) can mediate HBV direct infection and damage to human podocytes, and the NTCP157-165 locus is the main HBV entry site. The findings provide theoretical support for the pathogenesis of direct infection of HBV with kidney tissue. The findings provide a new target and theoretical basis for the treatment of HBV-related glomerulonephritis (HBV-GN). Blocking NTCP is a new target for the treatment of HBV-GN. We found that tacrolimus, a calcineurin inhibitor that blocks NTCP, can effectively treat HBV-GN. This study also provides a theoretical basis for the effective and safe treatment of immunosuppressant tacrolimus for HBV-GN.


Assuntos
Glomerulonefrite , Hepatite B , Podócitos , Simportadores , Humanos , Vírus da Hepatite B/genética , Tacrolimo/metabolismo , Podócitos/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , RNA Interferente Pequeno
4.
Nat Metab ; 6(2): 238-253, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38278946

RESUMO

Biphasic glucose-stimulated insulin secretion (GSIS) is essential for blood glucose regulation, but a mechanistic model incorporating the recently identified islet ß cell heterogeneity remains elusive. Here, we show that insulin secretion is spatially and dynamically heterogeneous across the islet. Using a zinc-based fluorophore with spinning-disc confocal microscopy, we reveal that approximately 40% of islet cells, which we call readily releasable ß cells (RRßs), are responsible for 80% of insulin exocytosis events. Although glucose up to 18.2 mM fully mobilized RRßs to release insulin synchronously (first phase), even higher glucose concentrations enhanced the sustained secretion from these cells (second phase). Release-incompetent ß cells show similarities to RRßs in glucose-evoked Ca2+ transients but exhibit Ca2+-exocytosis coupling deficiency. A decreased number of RRßs and their altered secretory ability are associated with impaired GSIS progression in ob/ob mice. Our data reveal functional heterogeneity at the level of exocytosis among ß cells and identify RRßs as a subpopulation of ß cells that make a disproportionally large contribution to biphasic GSIS from mouse islets.


Assuntos
Insulinas Bifásicas , Células Secretoras de Insulina , Camundongos , Animais , Secreção de Insulina , Insulinas Bifásicas/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Exocitose/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-38006465

RESUMO

BACKGROUND: Ferroptosis and lncRNAs both play crucial roles in cancers. But the roles of ferroptosis-related lncRNAs (FRLncs) in HBV-related HCC (HBV-HCC) remain ambiguous. METHODS: The gene expression profile and clinical data were originated from the Cancer Genome Atlas (TCGA) database. The risk signature was constructed by FRLncs based on the Cox regression analysis. The survival curve, Cox regression analysis, and time-dependent receiver operating characteristic (ROC) curve were adopted to verify the independence and reliability of the signature. A nomogram was established. Immune-infiltrating cells, immune functions, and checkpoints were analyzed. RESULTS: A risk signature composed of 7 FRLncs (LINC00942, AC131009.1, POLH-AS1, AC090772.3, MKLN1-AS, AC009403.1, AL031985.3) was constructed and divided HBV-HCC patients into high- and low-risk groups. Patients in the high-risk group showed a poor prognosis. The area under curves (AUC) of the signature for 1-, 3-, and 5-year was satisfactory. A nomogram composed of gender, stage, age, grade, and risk signature was established. The risk signature and nomogram displayed appreciable independence and reliability in HBV-HCC patients. The T-cell CD8 + , monocyte, and macrophage M1 were expressed differently significantly in HCC patients, while macrophage M2 showed an obvious difference in the HBV-HCC patients between the different risk groups. PDCD1 and CTL4 were expressed higher in the high-risk group of HCC patients. CONCLUSION: A 7-lncRNA signature was identified as a potential prognostic predictor for HBV-HCC patients. Immune therapy may be a promising strategy for HCC patients, especially HBV-HCC patients.

6.
Sensors (Basel) ; 23(20)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37896725

RESUMO

Satellite pose estimation plays a crucial role within the aerospace field, impacting satellite positioning, navigation, control, orbit design, on-orbit maintenance (OOM), and collision avoidance. However, the accuracy of vision-based pose estimation is severely constrained by the complex spatial environment, including variable solar illumination and the diffuse reflection of the Earth's background. To overcome these problems, we introduce a novel satellite pose estimation network, FilterformerPose, which uses a convolutional neural network (CNN) backbone for feature learning and extracts feature maps at various CNN layers. Subsequently, these maps are fed into distinct translation and orientation regression networks, effectively decoupling object translation and orientation information. Within the pose regression network, we have devised a filter-based transformer encoder model, named filterformer, and constructed a hypernetwork-like design based on the filter self-attention mechanism to effectively remove noise and generate adaptive weight information. The related experiments were conducted using the Unreal Rendered Spacecraft On-Orbit (URSO) dataset, yielding superior results compared to alternative methods. We also achieved better results in the camera pose localization task, indicating that FilterformerPose can be adapted to other computer vision downstream tasks.

7.
Nature ; 623(7987): 531-537, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853122

RESUMO

Achieving both high efficiency and long-term stability is the key to the commercialization of perovskite solar cells (PSCs)1,2. However, the diversity of perovskite (ABX3) compositions and phases makes it challenging to fabricate high-quality films3-5. Perovskite formation relies on the reaction between AX and BX2, whereas most conventional methods for film-growth regulation are based solely on the interaction with the BX2 component. Herein, we demonstrate an alternative approach to modulate reaction kinetics by anion-π interaction between AX and hexafluorobenzene (HFB). Notably, these two approaches are independent but work together to establish 'dual-site regulation', which achieves a delicate control over the reaction between AX and BX2 without unwanted intermediates. The resultant formamidinium lead halides (FAPbI3) films exhibit fewer defects, redshifted absorption and high phase purity without detectable nanoscale δ phase. Consequently, we achieved PSCs with power conversion efficiency (PCE) up to 26.07% for a 0.08-cm2 device (25.8% certified) and 24.63% for a 1-cm2 device. The device also kept 94% of its initial PCE after maximum power point (MPP) tracking for 1,258 h under full-spectrum AM 1.5 G sunlight at 50 ± 5 °C. This method expands the range of chemical interactions that occur in perovskite precursors by exploring anion-π interactions and highlights the importance of the AX component as a new and effective working site to improved photovoltaic devices with high quality and phase purity.

9.
Acupunct Herb Med ; 3(2): 83-95, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37810368

RESUMO

Coronavirus disease 2019 (COVID-19) is a major disease that threatens human life and health. Its pathogenesis is complex and still not fully clarified. The clinical treatment is mainly supportive and lacks specific treatment methods. Acupuncture treatment can inhibit immune inflammatory reactions, neuroinflammatory reactions, oxidative stress levels, and hypothalamus-pituitary-adrenal (HPA) axis activity, improve lung function, and relieve migraine, fatigue, anxiety, and depression. However, whether acupuncture treatment is suitable for treating these symptoms in patients with COVID-19 still needs to be investigated. For this review, the literature was systematically searched for multiple databases to summarize the mechanisms of acupuncture treatment for COVID-19-related symptoms and complications. A complex network analysis of acupoints and symptoms was also performed to clarify acupoint selection in the acupuncture treatment of symptoms related to COVID-19. The evidence indicates that acupuncture can improve the respiratory, digestive, nervous, and mental and psychological symptoms related to COVID-19 by inhibiting immune inflammatory reactions, regulating intestinal flora, mitochondrial function, oxidative stress level, cardiomyocyte apoptosis, neurotransmitter release, and HPA axis activity, and alleviating basic diseases such as diseases of the vascular system. Acupuncture can improve various clinical and concomitant symptoms of COVID-19; however, its mechanism of action is complex and requires further study. Graphical abstract: http://links.lww.com/AHM/A54.

10.
World J Gastroenterol ; 29(30): 4616-4627, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37662858

RESUMO

After being ingested and entering the human stomach, Helicobacter pylori (H. pylori) adopts several effective strategies to adhere to and colonize the gastric mucosa and move to different regions of the stomach to obtain more nutrients and escape from the harsher environments of the stomach, leading to acute infection and chronic gastritis, which is the basis of malignant gastric tumors. The endoscopic manifestations and pathological features of H. pylori infection are diverse and vary with the duration of infection. In this review, we describe the endoscopic manifestations of each stage of H. pylori gastritis and then reveal the potential mechanisms of bacterial intragastric colonization and migration from the perspective of endoscopists to provide direction for future research on the effective therapy and management of H. pylori infection.


Assuntos
Gastrite , Helicobacter pylori , Humanos , Mucosa Gástrica , Endoscopia
12.
Nat Commun ; 14(1): 5945, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741832

RESUMO

Microsatellite-stable colorectal cancer (MSS-CRC) is highly refractory to immunotherapy. Understanding tumor-intrinsic determinants of immunotherapy resistance is critical to improve MSS-CRC patient outcomes. Here, we demonstrate that high tumor expression of the core autophagy gene ATG16L1 is associated with poor clinical response to anti-PD-L1 therapy in KRAS-mutant tumors from IMblaze370 (NCT02788279), a large phase III clinical trial of atezolizumab (anti-PD-L1) in advanced metastatic MSS-CRC. Deletion of Atg16l1 in engineered murine colon cancer organoids inhibits tumor growth in primary (colon) and metastatic (liver and lung) niches in syngeneic female hosts, primarily due to increased sensitivity to IFN-γ-mediated immune pressure. ATG16L1 deficiency enhances programmed cell death of colon cancer organoids induced by IFN-γ and TNF, thus increasing their sensitivity to host immunity. In parallel, ATG16L1 deficiency reduces tumor stem-like populations in vivo independently of adaptive immune pressure. This work reveals autophagy as a clinically relevant mechanism of immune evasion and tumor fitness in MSS-CRC and provides a rationale for autophagy inhibition to boost immunotherapy responses in the clinic.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Animais , Feminino , Humanos , Camundongos , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Genes Reguladores , Fígado , Ensaios Clínicos Fase III como Assunto
13.
Animals (Basel) ; 13(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37627453

RESUMO

Biological feed is a feed product developed through bioengineering technologies such as fermentation engineering, enzyme engineering, protein engineering, and genetic engineering. It possesses functional characteristics of high nutritional value and good palatability that can improve feed utilization, replace antibiotics, enhance the health level of livestock and poultry, improve the quality of livestock products, and promote a better breeding environment. A comprehensive review is provided on the types of biological feed, their mechanism of action, fermenting strains, fermenting raw material resources, and their current status in animal production to facilitate in-depth research and development of applications.

14.
Chin Med ; 18(1): 106, 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37635258

RESUMO

BACKGROUND: Sepsis poses a serious threat to human life and health, with limited options for current clinical treatments. Acupuncture plays an active role in treating sepsis. However, previous studies have focused on the neuromodulatory effect of acupuncture, neglecting its network modulatory effect. Exosomes, as a new way of intercellular communication, may play an important role in transmitting acupuncture information. This paper explores the possibility of electroacupuncture-driven endogenous circulating serum exosomes and their carried miRNAs as a potential treatment for sepsis. METHODS: The sepsis mouse model was established by intraperitoneal injection of lipopolysaccharide (LPS) (12 mg/kg, 24 mg/kg), and EA (continuous wave, 10 Hz, intensity 5) or intraperitoneal injection of Acupuncture Exosomes (Acu-exo) were performed before the model establishment. The therapeutic effect was evaluated by survival rate, ELISA, H&E staining and lung wet/dry weight ration (W/D). In vivo imaging of small animals was used to observe the accumulation of Acu-exo in various organs of sepsis mice. LPS was used to induce macrophages in cell experiments, and the effect of Acu-exo on macrophage inflammatory cytokines was observed. In addition, The miRNA sequencing method was further used to detect the serum exosomes of normal and EA-treated mice, and combined with network biology analysis methods to screen possible key targets. RESULTS: EA and Acu-exo reduced the W/D and lung tissue damage in sepsis mice, down-regulated the expression of serum inflammatory cytokines TNF-α and IL-6, and increased the survival rate of sepsis mice. In vivo imaging of small animals found that Acu-exo were accumulated in the lungs of sepsis mice. Cell experiments proved that Acu-exo down-regulated the expression of inflammatory cytokines TNF-α, IL-6 and IL-1ß to alleviate the inflammatory response induced by LPS in macrophages. MiRNA sequencing revealed 53 differentially expressed miRNAs, and network biology analysis revealed the key targets of Acu-exo in sepsis treatment. CONCLUSION: Electroacupuncture-driven endogenous circulating serum exosomes and their carried miRNAs may be a potential treatment for sepsis.

15.
Nat Mater ; 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537355

RESUMO

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

16.
Hepatol Int ; 2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37332023

RESUMO

INTRODUCTION: We aimed to determine the diagnostic criteria of myosteatosis in a Chinese population and investigate the effect of skeletal muscle abnormalities on the outcomes of cirrhotic patients. METHODS: Totally 911 volunteers were recruited to determine the diagnostic criteria and impact factors of myosteatosis, and 480 cirrhotic patients were enrolled to verify the value of muscle alterations for prognosis prediction and establish new noninvasive prognostic strategies. RESULTS: Multivariate analysis showed age, sex, weight, waist circumference, and biceps circumference had a remarkable influence on the L3 skeletal muscle density (L3-SMD). Based on the cut-off of a mean - 1.28 × SD among adults aged < 60 years, the diagnostic criteria for myosteatosis was L3-SMD < 38.93 Hu in males and L3-SMD < 32.82 Hu in females. Myosteatosis rather than sarcopenia has a close correlation with portal hypertension. The concurrence of sarcopenia and myosteatosis not only is associated with poor liver function but also evidently reduced the overall and liver transplantation-free survival of cirrhotic patients (p < 0.001). According to the stepwise Cox regression hazard model analysis, we established nomograms including TBil, albumin, history of HE, ascites grade, sarcopenia, and myosteatosis for easily determining survival probabilities in cirrhotic patients. The AUC is 0.874 (95% CI 0.800-0.949) for 6-month survival, 0.831 (95% CI 0.764-0.898) for 1-year survival, and 0.813 (95% CI 0.756-0.871) for 2-year survival prediction, respectively. CONCLUSIONS: This study provides evidence of the significant correlation between skeletal muscle alterations and poor outcomes of cirrhosis, and establishes valid and convenient nomograms incorporating musculoskeletal disorders for the prognostic prediction of liver cirrhosis. Further large-scale prospective studies are necessary to verify the value of the nomograms.

17.
Front Pharmacol ; 14: 1158945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033644

RESUMO

Inflammatory bowel disease (IBD) is a chronic recurrent intestinal disease. The incidence rate of IBD is increasing year by year, which seriously endangers human health worldwide. More and more studies have shown that medicinal plants or their main phytochemicals have great potential in the treatment of intestinal diseases. However, the disadvantages of low oral absorption rate, low biological distribution and low systemic bioavailability limit their clinical application to a certain extent. In recent years, the application of nanotechnology has made it possible to treat IBD. Nanoparticles (NPs) drug delivery system has attracted special attention in the treatment of IBD due to its small size, low immunogenicity, surface modification diversity, targeting and other advantages. Synthetic nanoparticles and extracellular vehicles (EVs) can deliver drug components to colon, and play a role in anti-inflammation, regulation of oxidative stress, improvement of intestinal flora, etc. In addition, some medicinal plants can secrete EVs by themselves, and carry biological molecules with therapeutic effects to act on the intestine. Some clinical trials to evaluate the safety, tolerance, toxicity and effectiveness of EVs-loaded drugs in IBD are also progressing steadily. This review introduces that synthetic nanoparticles and medicinal plants derived EVs can play an important role in the treatment of IBD by carrying the effective active phytochemicals of medicinal plants, and discuss the limitations of current research and future research needs, providing a scientific and reliable basis and perspective for further clinical application and promotion.

18.
Angew Chem Int Ed Engl ; 62(24): e202303176, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37060295

RESUMO

Possessed with advantageous optoelectronic properties, perovskites have boosted the rapid development of solution-processed solar cells. The performance of perovskite solar cells (PSCs) is significantly weakened by the carrier loss at grain boundary grooves (GBGs); however, it receives limited attention and there lacks effective approach to solve this issue. Herein, for the first time, we constructed the tungstate/perovskite heterointerface via a "two step" in situ reaction approach that provides effective defect passivation and ensures efficient carrier dynamics at the GBGs. The exposed perovskite at grain boundaries is converted to wide-band-gap PbWO4 via an in-situ reaction between Pb2+ and tungstate ions, which passivate defects due to the strong ionic bonding. Moreover, recombination loss is further suppressed via the heterointerface energetics modification based on an additional transformation from PbWO4 to CaWO4 . PSCs based on this groove modification strategy showed good universality in both normal and inverted structure, with an improved efficiency of 23.25 % in the n-i-p device and 23.33 % in the p-i-n device. Stable power output of the modified device could maintain 91.7 % after around 1100 h, and the device efficiency could retain 92.5 % after aging in air for around 2110 h, and 93.1 % after aging at 85 °C in N2 for 972 h.

19.
Heliyon ; 9(3): e14238, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36950615

RESUMO

The ability of stem cells to rapidly proliferate and differentiate is integral to the steady-state maintenance of tissues with high turnover such as the blood and intestine. Mutations that alter these processes can cause primary immunodeficiencies, malignancies and defects in barrier function. The Rho-kinases, Rock1 and Rock2, regulate cell shape and cytoskeletal rearrangement, activities essential to mitosis. Here, we use inducible gene targeting to ablate Rock1 and Rock2 in adult mice, and identify an obligate requirement for these enzymes in the preservation of the hematopoietic and gastrointestinal systems. Hematopoietic cell progenitors devoid of Rho-kinases display cell cycle arrest, blocking the differentiation to mature blood lineages. Similarly, these mice exhibit impaired epithelial cell renewal in the small intestine, which is ultimately fatal. Our data reveal a novel role for these kinases in the proliferation and viability of stem cells and their progenitors, which is vital to maintaining the steady-state integrity of these organ systems.

20.
Proc Natl Acad Sci U S A ; 120(13): e2213650120, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36940334

RESUMO

Misfit dislocations at a heteroepitaxial interface produce huge strain and, thus, have a significant impact on the properties of the interface. Here, we use scanning transmission electron microscopy to demonstrate a quantitative unit-cell-by-unit-cell mapping of the lattice parameters and octahedral rotations around misfit dislocations at the BiFeO3/SrRuO3 interface. We find that huge strain field is achieved near dislocations, i.e., above 5% within the first three unit cells of the core, which is typically larger than that achieved from the regular epitaxy thin-film approach, thus significantly altering the magnitude and direction of the local ferroelectric dipole in BiFeO3 and magnetic moments in SrRuO3 near the interface. The strain field and, thus, the structural distortion can be further tuned by the dislocation type. Our atomic-scale study helps us to understand the effects of dislocations in this ferroelectricity/ferromagnetism heterostructure. Such defect engineering allows us to tune the local ferroelectric and ferromagnetic order parameters and the interface electromagnetic coupling, providing new opportunities to design nanosized electronic and spintronic devices.

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