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Ferroelectricity has long been speculated to have important biological functions, although its very existence in biology has never been firmly established. Here, we present compelling evidence that elastin, the key ECM protein found in connective tissues, is ferroelectric, and we elucidate the molecular mechanism of its switching. Nanoscale piezoresponse force microscopy and macroscopic pyroelectric measurements both show that elastin retains ferroelectricity at 473 K, with polarization on the order of 1 µC/cm(2), whereas coarse-grained molecular dynamics simulations predict similar polarization with a Curie temperature of 580 K, which is higher than most synthetic molecular ferroelectrics. The polarization of elastin is found to be intrinsic in tropoelastin at the monomer level, analogous to the unit cell level polarization in classical perovskite ferroelectrics, and it switches via thermally activated cooperative rotation of dipoles. Our study sheds light onto a long-standing question on ferroelectric switching in biology and establishes ferroelectricity as an important biophysical property of proteins. This is a critical first step toward resolving its physiological significance and pathological implications.
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Elastina/química , Eletricidade , Animais , Elastina/fisiologia , Microscopia Eletrônica de Transmissão , Simulação de Dinâmica Molecular , Suínos , TermogravimetriaRESUMO
Taking advantage of the strong adsorption characteristics of coffee grounds (CGs) and coffee ground biochar (CGB), this research employed equal amounts of 2%, 4%, 6%, and 8% CGs and CGB to replace cement. This study thereby examined the impacts of CGs and CGB on cement compressive strength, as well as their abilities to adsorb chloride ions and formaldehyde. X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG-DTG), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were employed to investigate the hydration mechanism and characterize the microscopic structure. The results show the following: (1) The presence of a substantial quantity of organic compounds in CGs is found to have an adverse effect on both the compressive strength and hydration degree of the sample. The use of CGB after high-temperature pyrolysis of phosphoric acid can effectively improve the negative impact of organic compounds on the sample. (2) The addition of CGs reduces the adsorption of chloride ions by cement, primarily due to the presence of fewer hydration products. However, when CGB was incorporated into cement, it enhanced the ability to adsorb chloride ions. (3) Cement containing 8% CGB content can slightly enhance the adsorption of formaldehyde. However, the cement sample with 8% CGB content exhibited the most significant ability to adsorb formaldehyde.
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Purpose: The purpose of the present study was to identify predictors of severe white matter hyperintensity (WMH) with obesity (SWO), and to build a prediction model for screening obese people with severe WMH without Nuclear Magnetic Resonance Imaging (MRI) examination. Patients subjects and methods: From September 2020 to October 2021, 650 patients with WMH were recruited consecutively. The subjects were divided into two groups, SWO group and non-SWO group. Univariate and Logistic regression analysis were was applied to explore the potential predictors of SWO. The Youden index method was adopted to determine the best cut-off value in the establishment of the prediction model of SWO. Each parameter had two options, low and high. The score table of the prediction model and nomogram based on the logistic regression were constructed. Of the 650 subjects, 487 subjects (75%) were randomly assigned to the training group and 163 subjects (25%) to the validation group. By resampling the area under the curve (AUC) of the subject's operating characteristics and calibration curves 1,000 times, nomogram performance was verified. A decision curve analysis (DCA) was used to evaluate the nomogram's clinical usefulness. By resampling the area under the curve (AUC) of the subject's operating characteristics and calibration curves 1,000 times, nomogram performance was verified. A decision curve analysis (DCA) was used to evaluate the nomogram's clinical usefulness. Results: Logistic regression demonstrated that hypertension, uric acid (UA), complement 3 (C3) and Interleukin 8 (IL-8) were independent risk factors for SWO. Hypertension, UA, C3, IL-8, folic acid (FA), fasting C-peptide (FCP) and eosinophil could be used to predict the occurrence of SWO in the prediction models, with a good diagnostic performance, Areas Under Curves (AUC) of Total score was 0.823 (95% CI: 0.760-0.885, p < 0.001), sensitivity of 60.0%, specificity of 91.4%. In the development group, the nomogram's AUC (C statistic) was 0.829 (95% CI: 0.760-0.899), while in the validation group, it was 0.835 (95% CI: 0.696, 0.975). In both the development and validation groups, the calibration curves following 1,000 bootstraps showed a satisfactory fit between the observed and predicted probabilities. DCA showed that the nomogram had great clinical utility. Conclusion: Hypertension, UA, C3, IL-8, FA, FCP and eosinophil models had the potential to predict the incidence of SWO. When the total score of the model exceeded 9 points, the risk of SWO would increase significantly, and the nomogram enabled visualization of the patient's WMH risk. The application prospect of our models mainly lied in the convenient screening of SWO without MRI examination in order to detect SWO and control the WMH hazards early.
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The present study evaluated the potential of endogenous enzymes and probiotics in transforming bioactive metabolites to reduce the purgative effect and improve the functional activity of Cassiae Semen and verified and revealed the biotransformation effect of endogenous enzymes. Although probiotics, especially Lactobacillus rhamnosus, exerted the transformation effect, the endogenous enzymes proved to be more effective in transforming the components of Cassiae Semen. After biotransformation by endogenous enzymes for 12 h, the levels of six anthraquinones in Cassiae Semen increased by at least 2.98-fold, and free anthraquinones, total phenolics, and antioxidant activity also showed significant improvement, accompanied by an 82.2% reduction in combined anthraquinones responsible for the purgative effect of Cassiae Semen. Further metabolomic analysis revealed that the biotransformation effect of endogenous enzymes on the bioactive metabolites of Cassiae Semen was complex and diverse, and the biotransformation of quinones and flavonoids was particularly prominent and occurred by three primary mechanisms, hydrolyzation, methylation, and dimerization, might under the action of glycosyl hydrolases, SAM-dependent methyltransferases, and CYP450s. Accordingly, biotransformation by endogenous enzymes emerges as a mild, economical, food safety risk-free, and effective strategy to modify Cassiae Semen into an excellent functional food.
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Cassia , Medicamentos de Ervas Chinesas , Probióticos , Catárticos , Antraquinonas , Probióticos/análise , Sementes/química , BiotransformaçãoRESUMO
Elastin is an intriguing extracellular matrix protein present in all connective tissues of vertebrates, rendering essential elasticity to connective tissues subjected to repeated physiological stresses. Using piezoresponse force microscopy, we show that the polarity of aortic elastin is switchable by an electrical field, which may be associated with the recently discovered biological ferroelectricity in the aorta. More interestingly, it is discovered that the switching in aortic elastin is largely suppressed by glucose treatment, which appears to freeze the internal asymmetric polar structures of elastin, making it much harder to switch, or suppressing the switching completely. Such loss of ferroelectricity could have important physiological and pathological implications from aging to arteriosclerosis that are closely related to glycation of elastin.
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Aorta/química , Aorta/fisiologia , Elastina/química , Elastina/fisiologia , Glucose/química , Glucose/farmacologia , Animais , Aorta/efeitos dos fármacos , Fenômenos Eletromagnéticos , Microscopia de Força Atômica/métodos , SuínosRESUMO
Proper flowering is essential for the reproduction of all kinds of plants. Oat is an important cereal and forage crop; however, its cultivation is limited because it is a long-day plant. The molecular mechanism by which oats respond to different photoperiods is still unclear. In this study, oat plants were treated under long-day and short-day photoperiods for 10 days, 15 days, 20 days, 25 days, 30 days, 40 days and 50 days, respectively. Under the long-day treatment, oats entered the reproductive stage, while oats remained vegetative under the short-day treatment. Forty-two samples were subjected to RNA-Seq to compare the gene expression patterns of oat under long- and short-day photoperiods. A total of 634-5,974 differentially expressed genes (DEGs) were identified for each time point, while the floral organ primordium differentiation stage showed the largest number of DEGs, and the spikelet differentiation stage showed the smallest number. Gene Ontology (GO) analysis showed that the plant hormone signaling transduction and hormone metabolism processes significantly changed in the photoperiod regulation of flowering time in oat. Moreover, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Mapman analysis revealed that the DEGs were mainly concentrated in the circadian rhythm, protein antenna pathways and sucrose metabolism process. Additionally, transcription factors (TFs) involved in various flowering pathways were explored. Combining all this information, we established a molecular model of oat flowering induced by a long-day photoperiod. Taken together, the long-day photoperiod has a large effect at both the morphological and transcriptomic levels, and these responses ultimately promote flowering in oat. Our findings expand the understanding of oat as a long-day plant, and the explored genes could be used in molecular breeding to help break its cultivation limitations in the future.
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Miracle berry is well-known for its ability to convert sour foods to sweet. In this study, the secondary metabolites of miracle berry leaves (MBL) were identified by UPLC-DAD-MS, and its antiangiogenesis and anticancer activities were evaluated by using a zebrafish model and the MCF-7 xenograft mouse model, respectively. The result showed that 18 phenolic compounds were identified in MBL extract, and dominated by the derivatives of quercetin and myricetin. The MBL extract showed low toxicity and high antiangiogenesis activity, it significantly inhibited the subintestinal vein vessels development in zebrafish at very low concentration. Furthermore, the MBL extract could promote the apoptosis of tumor cells and significantly inhibit the growth of MCF-7 xenograft tumor. In addition, the analysis of metabolites revealed that the MBL extract inhibited tumor growth by activating the metabolic pathways of unsaturated fatty acids and purines. Overall, this study suggests that MBL extract can be used as a natural anticancer adjuvant in the fields of functional foods.
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Due to the low content of silicon and aluminum in red mud and the low reaction activity of red mud, when it was used to prepare composite cementitious materials, it was necessary to assist other aluminosilicates and improve their activity by certain methods. In this study, it was proposed to add slag to increase the percentage of silicon and aluminum in the system, and to improve the reactivity of the system through the activation effect of sulfate in phosphogypsum. The effects of slag and phosphogypsum contents on the mechanical properties and microstructures of composite cementitious materials were studied. X-ray diffraction analysis (XRD), thermogravimetric analysis (TG-DTG), and scanning electron microscopy (SEM) were used to analyze the effects of slag and phosphogypsum contents on the hydration products, microstructure, and strength formation mechanism of composite cementitious materials. The results show that with the increase of slag, the strength of the composite cementitious material increases gradually. When the slag content is 50%, the 28-day compressive strength reaches a maximum of about 14 MPa. Compared with the composite material without phosphogypsum, the composite cementitious material with 10-20% phosphogypsum showed higher strength properties, in which the 28-day compressive strength exceeds 24 MPa. The main reason for this is that the sulfate in phosphogypsum can cause the composite cementitious material to generate a large amount of ettringite and accelerate the dissolution of red mud and slag, increasing the release of aluminates, silicates, and Ca2+ to form more C-(A)-S-H and ettringite. In addition, a large amount of C-(A)-S-H makes ettringite and unreacted particles combine into a uniform and compact structure, thus improving the strength. When the content of phosphogypsum exceeds 40%, the 28-day compressive strength of the composite cementitious material drops below 12 MPa due to the presence of fewer hydration products and the expansion of ettringite.
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As a common macromolecular carbohydrate, pectin has a strong affinity for Pb2+. An ethylenediamine modified pectin (EP48) with 48 % of amidation was prepared and exhibited great removal efficiency towards Pb2+ in our previous study. However, the EP48 has drawbacks in adsorption including low mechanical strength and difficulty in separation. In this study, EP48 was compounded with sodium alginate (Alg) and Fe3O4 to synthesize EP48/Alg/Fe3O4 microsphere. The physicochemical properties and Pb2+ adsorption characteristics of microsphere were analyzed. It was found that the microsphere exhibited good thermal stability, mechanical strength, porous structure, as well as acid tolerance. The pseudo-second-order model well described the kinetics of adsorption process, indicating the chemical adsorption is dominant. The Langmuir model fitted the experimental data well, and the maximum adsorption capacity reached 175.19 mg/g. Adsorption-desorption experiments showed that the removal rate of the microsphere maintained over 98.9 % after 10 cycles. The X-ray photoelectron spectroscopy (XPS) analyses revealed that the potential adsorption mechanism included ion-exchange and chelation. The above results suggested its potential use for the removal of Pb2+ from wastewater.
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Alginatos , Poluentes Químicos da Água , Alginatos/química , Pectinas , Poluentes Químicos da Água/química , Adsorção , Cinética , Concentração de Íons de HidrogênioRESUMO
Long-term exposures to low-dose radiation (LDR) may trigger several specific biological responses, including dysregulation of the immune and inflammatory systems. Here, we examined whether biodosimetry of LDR can be used to protect tissues from radiation or assess cancer risk. Mice were subjected to gamma-irradiation with repeated or single-dose LDR, and then the organ indices, peripheral hemogram, and blood biochemistry were analyzed. An antibody array was applied followed by enzyme-linked immunosorbent assay to evaluate the utility of multiple plasma proteins as biomarkers of repeated LDR in a murine model. LDR induced inapparent symptoms but slight variations in peripheral blood cell counts and alterations in blood biochemical indicator levels. Specific plasma proteins in the LDR groups were altered in response to a higher dose of irradiation at the same time points or a single-dose equivalent to the same total dose. Plasma levels of interleukin (IL)-5, IL-12p40, P-selectin, and serum amyloid A1 were associated with the LDR dose and thus may be useful as dosimetric predictors of LDR in mice. Estimating the levels of certain plasma proteins may yield promising biodosimetry parameters to accurately identify individuals exposed to LDR, facilitating risk assessment of long-term LDR exposure in individuals.
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OBJECTIVE: This study aimed to explore the correlation between white matter hyperintensity (WMH) and post-stroke depression (PSD) at 3 months, and to further investigate sex differences in the pathogenesis of PSD. METHODS: A total of 238 consecutive patients with acute cerebral infarction were recruited. PSD was assessed at 2 weeks and at 3 months after stroke onset. All stroke cases were divided into four subgroups according to the diagnosis of depression at two time nodes: continuous depression; depression remission; late-onset PSD; and continuous non-depression. The Fazekas and Scheltens visual rating scales were adopted to assess WMH. RESULTS: Logistic regression revealed that the presence of periventricular white matter hyperintensity (PVWMH) at baseline in male patients was an independent risk factor for PSD at 3 months. Further subgroup analysis revealed that PVWMH was associated with late-onset PSD in males, but not with continuous depression 3 months after stroke. Male acute stroke patients with PVWMH at baseline were more likely to develop PSD at 3 months, especially late-onset PSD. CONCLUSION: Our data suggest that sex differences may influence the pathogenesis of PSD.
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BACKGROUND: Currently, there are no reliable indicators for predicting intravenous immunoglobulin resistance and coronary artery lesions in the early stage of Kawasaki disease. METHODS: A total of 300 patients with Kawasaki disease were studied retrospectively. Laboratory data were compared between the intravenous immunoglobulin resistant (29 patients) and responsive groups, and between the groups with coronary artery lesions (48 patients) and without coronary artery lesions. RESULTS: The intravenous immunoglobulin resistant group had significantly higher D-dimer, globulin, interleukin-6 and serum ferritin levels in comparison to the intravenous immunoglobulin responder group. D-dimer level had a sensitivity of 87.0% and a specificity of 56.3% for predicting intravenous immunoglobulin resistance at a cutoff point of 1.09 mg/L. Globulin had a sensitivity of 62.1% and a specificity of 82.3% for predicting intravenous immunoglobulin resistance at a cutoff point of 34.7 g/L. Serum ferritin level had a sensitivity of 42.9% and a specificity of 88.8% for predicting intravenous immunoglobulin resistance at a cutoff point of 269.7 ng/mL. The patients with coronary artery lesions had higher D-dimer and tumor necrosis factor-α level. D-dimer level had a sensitivity of 50% and a specificity of 78.6% for predicting coronary artery lesions at a cutoff point of 1.84 mg/L. Based on analysis by multivariate logistic regression, serum ferritin and globulin were independent risks for intravenous immunoglobulin resistance, D-dimer was independent risk for coronary artery lesions. CONCLUSIONS: Elevated serum ferritin, globulin and D-dimer levels are significantly associated with intravenous immunoglobulin resistance in Kawasaki disease. Moreover, serum D-dimer is significantly increased in Kawasaki disease with coronary artery lesions.
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Doença da Artéria Coronariana/epidemiologia , Resistência a Medicamentos , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Adolescente , Área Sob a Curva , Biomarcadores/sangue , Criança , Pré-Escolar , China , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Bases de Dados Factuais , Ferritinas/sangue , Hospitais Pediátricos , Humanos , Imunoglobulina G/uso terapêutico , Lactente , Interleucina-6/sangue , Modelos Logísticos , Masculino , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Soroglobulinas/análise , Índice de Gravidade de DoençaRESUMO
OBJECTIVES: To clarify the independent risk factors and construct a scoring system for Kawasaki disease (KD) with coronary artery lesions (CAL) at acute and subacute stages. METHOD: Data of KD inpatients at acute and subacute stages were reviewed in a tertiary care center from January 2009 to December 2014. RESULTS: A total of 2305 acute and subacute KD cases were enrolled in this study with a CAL rate of 24.1%. The OR (95%CI) values of male, total fever duration ≥ 8 days, IVIG resistance (IVIGR), albumin (ALB) ≤ 35.9 g/L, eosionphils (EO) ≥ 2.2%, and monocytes (MO) ≥ 5.9% were 1.45 (1.15-1.82), 1.78 (1.43-2.22), 1.42 (1.09-1.85), 1.53 (1.23-1.91), 1.17 (0.94-1.45), and 1.37 (1.09-1.69), respectively. In patients ≤ 6 months old, the OR (95%CI) values for total fever duration ≥8 days, delayed diagnosis, and ALB ≤ 35.9 g/L were 3.61 (2.02-6.45), 3.49 (1.49-8.16), and 2.07 (1.14-3.74), respectively. ROC curve showed that the AUC value and sensitivity and specificity of predicting KD with CAL in patients ≤ 6 months old were 0.731, 64.7%, and 80.9%, respectively. CONCLUSIONS: The independent risk factors for acute and subacute KD combined with CAL, including being a boy, long fever duration, IVIGR, low ALB, elevated EO, and MO. Joint of parameters (total fever duration ≥ 8 days, delayed diagnosis, and ALB ≤ 35.9 g/L) can be used to predict the occurrence of CAL in KD patients ≤ 6 months old.
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Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/patologia , Febre/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Pré-Escolar , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/patologia , Feminino , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/patologia , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais , Fatores de TempoRESUMO
Objective: To explore the correlationship among white matter hyperintensities (WMHs), miR-92a-3p and early-onset post-stroke depression (PSD). Methods: We recruited consecutively 238 patients with acute cerebral infarction and MRI examination in the Department of neurology, Ruijin hospital, Shanghai Jiaotong University School of Medicine. The diagnosis of early-onset PSD was made in accordance with DSM-IV criteria for depression in 2 weeks after stroke. Clinical information and assessments of stroke severity were recorded on admission. The analysis of plasma miR-92a-3p was performed using quantitative PCR at the same time. WMHs were evaluated by the Fazekas and Scheltens visual rating scales. The relationship among WMHs, miR-92a-3p and PSD were analyzed by SPSS 22.0 software. Results: Logistic regression demonstrated that periventricular WMHs (PVWMHs) in frontal caps was an independent risk factor with early-onset PSD (OR = 1.579, 95% CI: 1.040-2.397, p = 0.032). The age and numbers of lacunes were related to frontal PVWMHs. Plasma miR-92a-3p in the PSD group was higher compared with the non-depressed group. Receiver operating curve analysis revealed that miR-92a-3p could predict early-onset PSD with 90% sensitivity and 90% specificity. The higher miR-92a-3p trended toward association with greater frontal PVWMHs. Conclusion: Acute ischemic stroke patients with frontal PVWMHs or a high plasma miR-92a-3p at baseline were more likely to develop early-onset PSD. MiR-92a-3p might be involved in the white matter impairment and post-stroke depression.
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Accurate scanning probing of magnetic materials at the nanoscale is essential for developing and characterizing magnetic nanostructures, yet quantitative analysis is difficult using the state of the art magnetic force microscopy, and has limited spatial resolution and sensitivity. In this communication, we develop a novel piezomagnetic force microscopy (PmFM) technique, with the imaging principle based on the detection of magnetostrictive response excited by an external magnetic field. In combination with the dual AC resonance tracking (DART) technique, the contact stiffness and energy dissipation of the samples can be simultaneously mapped along with the PmFM phase and amplitude, enabling quantitative probing of magnetic materials and structures at the nanoscale with high sensitivity and spatial resolution. PmFM has been applied to probe magnetic soft discs and cobalt ferrite thin films, demonstrating it as a powerful tool for a wide range of magnetic materials.
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Campos Magnéticos , Microscopia/instrumentação , Microscopia/métodosRESUMO
Carbon nanofibers (CNFs) have been synthesized from thermoplastic polyvinylpyrrolidone (PVP) using electrospinning in combination with a novel three-step heat treatment process, which successfully stabilizes the fibrous morphology before carbonization that was proven to be difficult for thermoplastic polymers other than polyacrylonitrile (PAN). These CNFs are both mesoporous and microporous with high surface areas without subsequent activation, and thus overcome the limitations of PAN based CNFs, and are processed in an environmentally friendly and more cost effective manner. The effects of heat treatment parameters and precursor concentration on the morphologies and porous properties of CNFs have been investigated, and their application as anodes for lithium ion batteries has also been demonstrated.
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Carbono/química , Nanofibras/química , Povidona/química , Resinas Acrílicas/química , Nanofibras/ultraestrutura , Porosidade , Propriedades de Superfície , TemperaturaRESUMO
Multiferroic CoFe(2)O(4)-Pb(Zr(0.52)Ti(0.48))O(3) core-shell nanofibers have been synthesized by coaxial electrospinning in combination with a sol-gel process. The core-shell configuration of nanofibers has been verified by scanning electron microscopy and transmission electron microscopy, and the spinel structure of CoFe(2)O(4) and perovskite structure of Pb(Zr(0.52)Ti(0.48))O(3) have been confirmed by X-ray diffraction and selected area electron diffraction. The multiferroic properties of core-shell nanofibers have been demonstrated by magnetic hysteresis and piezoresponse force microscopy, and their magnetoelectric coupling has been confirmed by evolution of piezoresponse under an external magnetic field, showing magnetically induced ferroelectric domain switching and changes in switching characteristics. The lateral magnetoelectric coefficient is estimated to be 2.95 × 10(4) mV/cmOe, two orders of magnitude higher than multiferroic thin films of similar composition.