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1.
Phys Rev Lett ; 132(11): 116701, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563939

RESUMO

Cavity magnonics is an emerging research area focusing on the coupling between magnons and photons. Despite its great potential for coherent information processing, it has been long restricted by the narrow interaction bandwidth. In this Letter, we theoretically propose and experimentally demonstrate a novel approach to achieve broadband photon-magnon coupling by adopting slow waves on engineered microwave waveguides. To the best of our knowledge, this is the first time that slow wave is combined with hybrid magnonics. Its unique properties promise great potentials for both fundamental research and practical applications, for instance, by deepening our understanding of the light-matter interaction in the slow wave regime and providing high-efficiency spin wave transducers. The device concept can be extended to other systems such as optomagnonics and magnomechanics, opening up new directions for hybrid magnonics.

2.
Nano Lett ; 23(11): 4807-4814, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37224193

RESUMO

Heterogeneities in structure and polarization have been employed to enhance the energy storage properties of ferroelectric films. The presence of nonpolar phases, however, weakens the net polarization. Here, we achieve a slush-like polar state with fine domains of different ferroelectric polar phases by narrowing the large combinatorial space of likely candidates using machine learning methods. The formation of the slush-like polar state at the nanoscale in cation-doped BaTiO3 films is simulated by phase field simulation and confirmed by aberration-corrected scanning transmission electron microscopy. The large polarization and the delayed polarization saturation lead to greatly enhanced energy density of 80 J/cm3 and transfer efficiency of 85% over a wide temperature range. Such a data-driven design recipe for a slush-like polar state is generally applicable to quickly optimize functionalities of ferroelectric materials.

3.
Front Cell Infect Microbiol ; 13: 1139556, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180431

RESUMO

Background: S100A8/A9, which is a member of S100 proteins, may be involved in the pathophysiology of Community-acquired pneumonia (CAP) that seriously threatens children's health. However, circulating markers to assess the severity of pneumonia in children are yet to be explored. Therefore, we aimed to investigate the diagnostic performance of serum S100A8/A9 level in determining the severity of CAP in children. Methods: In this prospective and observational study, we recruited 195 in-hospital children diagnosed with CAP. In comparison, 63 healthy children (HC) and 58 children with non-infectious pneumonia (pneumonitis) were included as control groups. Demographic and clinical data were collected. Serum S100A8/A9 levels, serum pro-calcitonin concentrations, and blood leucocyte counts were quantified. Results: The serum S100A8/A9 levels in patients with CAP was 1.59 ± 1.32 ng/mL, which was approximately five and two times higher than those in healthy controls and those in children with pneumonitis, respectively. Serum S100A8/A9 was elevated parallelly with the clinical pulmonary infection score. The sensitivity, specificity, and Youden's index of S100A8/A9 ≥1.25 ng/mL for predicting the severity of CAP in children was optimal. The area under the receiver operating characteristic curve of S100A8/A9 was the highest among the indices used to evaluate severity. Conclusions: S100A8/A9 may serve as a biomarker for predicting the severity of the condition in children with CAP and establishing treatment grading.


Assuntos
Calgranulina B , Pneumonia , Humanos , Criança , Estudos Prospectivos , Calgranulina A , Biomarcadores , Pneumonia/diagnóstico
5.
Comput Math Methods Med ; 2022: 5643742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529258

RESUMO

Objective: In this study, we screened out a type of differentially expressed circular RNA in infantile hemangioma (IH) cells and analyzed the mechanism in the malignant biological behavior of IH. Methods: Based on the GSE98795, GSE100682, and GSE43742 datasets, differential expression analysis of circRNAs, microRNAs, and mRNAs was performed. The relative expression level of RNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). MTT assay, Transwell, flow cytometry analysis, and western blot were used to study the effects of hsa_circ_0003570, hsa-miR-138-5p, and RGS5 on the proliferation and apoptosis of hemangioma endothelial cells (HEMECs). Results: The hsa_circ_0003570 and RGS5 mRNA were upregulated in HEMECs, but hsa-miR-138-5p was downregulated. Silencing of hsa_circ_0003570 inhibited the proliferation of HEMECs and promoted the apoptosis of HEMECs. The malignant biological behaviors of hsa_circ_0003570 on the proliferation and apoptosis of HEMECs were reversed by hsa-miR-138-5p. Hsa_circ_0003570 acted as the ceRNA of hsa-miR-138-5p and upregulated the expression of RGS5. Silencing of RGS5 inhibited the proliferation, migration, and invasion of HEMECs and promoted apoptosis. Conclusion: Hsa_circ_0003570 promotes IH cell proliferation and inhibits IH cell apoptosis through hsa-miR-138-5p/RGS5 axis.


Assuntos
Hemangioma , MicroRNAs , Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , Células Endoteliais/metabolismo , Hemangioma/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética
6.
ACS Appl Mater Interfaces ; 14(19): 22278-22286, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35523210

RESUMO

Relaxor ferroelectric-based energy storage systems are promising candidates for advanced applications as a result of their fast speed and high energy storage density. In the research field of ferroelectrics and relaxor ferroelectrics, the concept of solid solution is widely adopted to modify the overall properties and acquire superior performance. However, the combination between antiferroelectric and paraelectric materials was less studied and discussed. In this study, paraelectric barium hafnate (BaHfO3) and antiferroelectric lead hafnate (PbHfO3) are selected to demonstrate such a combination. A paraelectric to relaxor ferroelectric, to ferroelectric, and to antiferroelectric transition is observed by varying the composition x in the (Ba1-xPbx)HfO3 solid solution from 0 to 100%. It is noteworthy that ferroelectric phases can be realized without primal ferroelectric material. This study creates an original solid solution system with a rich spectrum of competing phases and demonstrates an approach to design relaxor ferroelectrics for energy storage applications and beyond.

7.
Acta Pharm ; 72(3): 415-425, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36651544

RESUMO

Respiratory syncytial virus (RSV) is the most common cause of small airways inflammation in the lungs (bronchiolitis) in neonates and immunocompromised adults. The deregulation of cellular and plasma components leads to increased morbidity and mortality. The activation of the clotting cascade plays a key role in the progression of disease severity during viral infection. The current investigation studied the effect of bivalirudin (BR) on the progression and cellular effects of RSV-induced infection in the neonatal mice model. Mice (5-7 days old) were inoculated intranasally with RSV with or without BR administration (2 mg kg-1 day-1, i.v.) for 2 weeks. Tissue histopathology, inflammatory signalling genes such as TLR, and cytokines were analyzed. The results showed pneumocytes exhibiting nuclear pyknosis, cellular infiltration in lung tissue and increased lung titers in RSV-infected mice compared to the control. Furthermore, RSV-infected mice demonstrated altered clotting parameters such as D-dimer, soluble thrombomodulin, and increased inflammatory cytokines IL-5, 6, IFN-γ, IL-13, and CXCL1. Additionally, the mRNA expression analysis displayed increased levels of IL-33, TLR3, and TLR7 genes in RSV-infected lung tissue. Further, to delineate the role of micro RNAs, the qRT-PCR analysis was done, and the results displayed an increase in miR-136, miR-30b, and let-7i. At the same time, the down-regulated expression of miR-221 in RSV-infected mice compared to the control. BR treatment reduced the cellular infiltration with reduced inflammatory cytokines and normalized clotting indices. Thus, the study shows that RSV infection induces specific changes in lung tissue and the clotting related signalling mechanism. Additionally, BR treatment significantly reduces bronchiolitis and prevents the severity of the infections suggesting that BR can possibly be used to reduce the viral-mediated infections in neonates.


Assuntos
MicroRNAs , Infecções por Vírus Respiratório Sincicial , Animais , Camundongos , Animais Recém-Nascidos , Antivirais/farmacologia , Antivirais/uso terapêutico , Antivirais/metabolismo , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/patologia , Pulmão/metabolismo , Pulmão/patologia , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/metabolismo , Citocinas/metabolismo , Camundongos Endogâmicos BALB C , Modelos Animais de Doenças
8.
ACS Appl Mater Interfaces ; 13(41): 48997-49006, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34617721

RESUMO

Narrowband terahertz (THz) radiation is crucial for high-resolution spectral identification, but a narrowband THz source driven by a femtosecond (fs) laser has remained scarce. Here, it is computationally predicted that a metal/dielectric/magnetoelastic heterostructure enables converting a fs laser pulse into a multicycle THz pulse with a narrow linewidth down to ∼1.5 GHz, which is in contrast to the single-cycle, broadband THz pulse from the existing fs-laser-excited emitters. It is shown that such narrowband THz pulse originates from the excitation and long-distance transport of THz spin waves in the magnetoelastic film, which can be enabled by a short strain pulse obtained from fs laser irradiation of the metal film when the thicknesses of the metal and magnetoelastic films both fall into a specific range. These results therefore reveal an approach to achieving optical generation of narrowband THz pulse based on heterostructure design, which also has implications in the design of THz magnonic devices.

9.
Cell Death Discov ; 7(1): 311, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34689169

RESUMO

A growing body of evidence suggests that long-chain non-coding RNA (lncRNA) plays an important role in the malignant biological behavior and drug resistance of glioblastoma (GBM) cells. In this study, we analyzed the role and potential mechanism of lncRNA TMEM161B-AS1 in the malignant biological behavior of GBM cells and temozolomide (TMZ) resistance. Studies have found that FANCD2 and CD44 are significantly related to the occurrence of GBM, TMZ resistance and the survival of GBM patients. Knockdown of TMEM161B-AS1 down-regulated the expression of FANCD2 and CD44 by sponging hsa-miR-27a-3p, inhibited the proliferation, migration, invasion and promoted apoptosis, ferroptosis of U87 cells and U251 cells. Down-regulation of lncRNA TMEM161B-AS1 and/or over-expression of hsa-miR-27a-3p down-regulated the expression of FANCD2 and CD44, and inhibited the tumor growth in nude mice. These results demonstrated that the lncRNA TMEM161B-AS1-hsa-miR-27a-3p-FANCD2/CD44 signal axis regulated the malignant biological behavior of GBM and TMZ resistance. These findings were expected to provide promising therapeutic targets for the treatment of glioma.

10.
Nat Commun ; 12(1): 322, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436572

RESUMO

Room-temperature skyrmions in magnetic multilayers are considered to be promising candidates for the next-generation spintronic devices. Several approaches have been developed to control skyrmions, but they either cause significant heat dissipation or require ultrahigh electric fields near the breakdown threshold. Here, we demonstrate electric-field control of skyrmions through strain-mediated magnetoelectric coupling in ferromagnetic/ferroelectric multiferroic heterostructures. We show the process of non-volatile creation of multiple skyrmions, reversible deformation and annihilation of a single skyrmion by performing magnetic force microscopy with in situ electric fields. Strain-induced changes in perpendicular magnetic anisotropy and interfacial Dzyaloshinskii-Moriya interaction strength are characterized experimentally. These experimental results, together with micromagnetic simulations, demonstrate that strain-mediated magnetoelectric coupling (via strain-induced changes in both the perpendicular magnetic anisotropy and interfacial Dzyaloshinskii-Moriya interaction is responsible for the observed electric-field control of skyrmions. Our work provides a platform to investigate electric-field control of skyrmions in multiferroic heterostructures and paves the way towards more energy-efficient skyrmion-based spintronics.

11.
Sci Rep ; 11(1): 2059, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479472

RESUMO

To investigate the relationships between LncRNA NNT-AS1, CRP, PCT and their interactions and the refractory mycoplasma pneumoniae pneumonia (RMPP) in children. Serum levels of LncRNA NNT-AS1 of RMPP and non-RMPP (NRMPP) patients were detected by real-time PCR, and were analyzed together with serum c-reactive protein (CRP) and procalcitonin (PCT). Correlations between LncRNA NNT-AS1 and CRP and PCT were analyzed by Pearson correlation test. The ROC curve was used to analyze the potential of LncRNA NNT-AS1, CRP and PCT as biomarkers for predicting RMPP. Logistic regression crossover model and the Excel compiled by Andersson et al. were used to analyze the interactions among the biomarkers. We found that LncRNA NNT-AS1, CRP and PCT were all highly expressed in patients with RMPP. LncRNA NNT-AS1 could positively correlate with the expressions of CRP and PCT, and jointly promote the occurrence of RMPP. The combined diagnosis of LncRNA NNT-AS1, CRP and PCT could predict the occurrence of RMPP.


Assuntos
Proteína C-Reativa/metabolismo , Pneumonia por Mycoplasma/sangue , Pró-Calcitonina/sangue , RNA Longo não Codificante/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Modelos Logísticos , Masculino , Mycoplasma pneumoniae/isolamento & purificação , Mycoplasma pneumoniae/patogenicidade , Pneumonia por Mycoplasma/microbiologia
12.
ACS Appl Mater Interfaces ; 13(1): 306-311, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382584

RESUMO

Photothermal therapy is a new type of tumor therapy with great potential. An ideal photothermal therapy agent should have high photothermal conversion effect, low biological toxicity, and degradability. The development of novel photothermal therapy agents with these properties is of great demand. In this study, we synthesized boron quantum dots (BQDs) with an ultrasmall hydrodynamic diameter. Both in vitro and in vivo studies show that the as-synthesized BQDs have good biological safety, high photoacoustic imaging performance, and photothermal conversion ability, which can be used for photoacoustic imaging-guided photothermal agents for tumor treatment. Our investigations confirm that the BQDs hold great promise in tumor theranostic applications.


Assuntos
Boro/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Pontos Quânticos/uso terapêutico , Animais , Boro/química , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Técnicas Fotoacústicas/métodos , Terapia Fototérmica/métodos , Pontos Quânticos/química , Nanomedicina Teranóstica/métodos
13.
Sci Adv ; 6(40)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33008898

RESUMO

Controlling magnetization dynamics is imperative for developing ultrafast spintronics and tunable microwave devices. However, the previous research has demonstrated limited electric-field modulation of the effective magnetic damping, a parameter that governs the magnetization dynamics. Here, we propose an approach to manipulate the damping by using the large damping enhancement induced by the two-magnon scattering and a nonlocal spin relaxation process in which spin currents are resonantly transported from antiferromagnetic domains to ferromagnetic matrix in a mixed-phased metallic alloy FeRh. This damping enhancement in FeRh is sensitive to its fraction of antiferromagnetic and ferromagnetic phases, which can be dynamically tuned by electric fields through a strain-mediated magnetoelectric coupling. In a heterostructure of FeRh and piezoelectric PMN-PT, we demonstrated a more than 120% modulation of the effective damping by electric fields during the antiferromagnetic-to-ferromagnetic phase transition. Our results demonstrate an efficient approach to controlling the magnetization dynamics, thus enabling low-power tunable electronics.

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