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1.
Phys Chem Chem Phys ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912970

RESUMO

The structures, stability, and electrochemical performances of Janus Ti2BST (T = O, Se) monolayers as anode materials for Na/K-ion batteries (NIBs/KIBs) are investigated by first-principles calculations. The results demonstrate that Ti2BST monolayers are mechanically, dynamically, and thermally stable. The electronic structures display good conductivity. Moreover, the low diffusion barriers of 0.107/0.039 eV (0.111/0.063 eV) for Na/K indicate that the Ti2BSO (Ti2BSSe) monolayer has excellent rate performance for NIBs/KIBs. Low average open circuit voltages (OCVs) (0.322-0.439 V) can produce a high voltage in NIBs/KIBs. Meanwhile, little structural changes during charge/discharge ensure great cycle stability. Especially, the Ti2BSO monolayer has a high theoretical capacity of 691.64/537.75 mA h g-1 for NIBs/KIBs. The outstanding performances demonstrate that the Ti2BST monolayers are potential anode materials for NIBs/KIBs.

2.
Nano Lett ; 23(20): 9399-9405, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877237

RESUMO

An accurate rule for predicting conductance is the cornerstone of developing molecular circuits and provides a promising solution for miniaturizing electric circuits. The successful prediction of series molecular circuits has proven the possibility of establishing a rule for molecular circuits under quantum mechanics. However, the quantitatively accurate prediction has not been validated by experiments for parallel molecular circuits. Here we used 1,3-dihydrobenzothiophene (DBT) to build the parallel molecular circuits. The theoretical simulation and single-molecule conductance measurements demonstrated that the conductance of the molecule containing one DBT is the unprecedented linear combination of the conductance of the two individual channels with respective contribution weights of 0.37 and 0.63. With these weights, the conductance of the molecule containing two DBTs is predicted as 1.81 nS, matching perfectly with the measured conductance (1.82 nS). This feature offers a potential rule for quantitatively predicting the conductance of parallel molecular circuits.

3.
Opt Express ; 31(6): 10348-10357, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157583

RESUMO

We report the slow-light enhanced spin-resolved in-plane emission from a single quantum dot (QD) in a photonic crystal waveguide (PCW). The slow light dispersions in PCWs are designed to match the emission wavelengths of single QDs. The resonance between two spin states emitted from a single QD and a slow light mode of a waveguide is investigated under a magnetic field with Faraday configuration. Two spin states of a single QD experience different degrees of enhancement as their emission wavelengths are shifted by combining diamagnetic and Zeeman effects with an optical excitation power control. A circular polarization degree up to 0.81 is achieved by changing the off-resonant excitation power. Strongly polarized photon emission enhanced by a slow light mode shows great potential to attain controllable spin-resolved photon sources for integrated optical quantum networks on chip.

4.
Inorg Chem ; 61(35): 13678-13684, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36007887

RESUMO

Porous organic polymer (POP) coated on a metal-organic framework (MOF) has the functions and advantages of MOF and POP at the same time and has excellent catalytic ability. In this study, an efficient dual-functional core-shell composite MOF@POP with Lewis acid and Brønsted base sites was synthesized using the impregnation method in which MIL-101(Cr) was the core component and polymelamine formaldehyde (PMF) was the shell component. Most importantly, the obtained MIL-101(Cr)@PMF showed perfect catalytic activity in the deacetalization-Knoevenagel tandem reaction. In addition, it could still maintain ultrahigh physical and chemical stability.

5.
Opt Express ; 29(19): 30735-30750, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34614794

RESUMO

The second-order topological photonic crystal with the 0D corner state provides a new way to investigate cavity quantum electrodynamics and develop topological nanophotonic devices with diverse functionalities. Here, we report on the optimization and robustness of the topological corner state in the second-order topological photonic crystal both in theory and in experiment. The topological nanocavity is formed based on the 2D generalized Su-Schrieffer-Heeger model. The quality factor of the corner state is optimized theoretically and experimentally by changing the gap between two photonic crystals or just modulating the position or size of the airholes surrounding the corner. The fabricated quality factors are further optimized by the surface passivation treatment which reduces surface absorption. A maximum quality factor of the fabricated devices is about 6000, which is the highest value ever reported for the active topological corner state. Furthermore, we demonstrate the robustness of the corner state against strong disorders including the bulk defect, edge defect, and even corner defect. Our results lay a solid foundation for further investigations and applications of the topological corner state, such as the investigation of a strong coupling regime and the development of optical devices for topological nanophotonic circuitry.

6.
Yi Chuan ; 43(7): 680-693, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284983

RESUMO

The number of Sertoli cells in the testis is a major regulator on the sperm production capacity. MicroRNAs (miRNAs) participate in regulating the proliferation and apoptosis of porcine immature Sertoli cells. However, the functions and mechanisms of action of most identified miRNAs in porcine Sertoli cells remain largely unknown. In the present study, based on our previous results from an EdU-based high-content screening assay, we further studied the mechanism of action of miR-191 on the proliferation and apoptosis of porcine immature Sertoli cells through flow cytometry, Western blotting, and dual-luciferase activity analyses. The results demonstrated that overexpression of miR-191 promoted cell cycle progression from G1 phase to the S and G2 phases, enhanced cell proliferation, and inhibited apoptosis in the porcine immature Sertoli cells, whereasmiR-191 inhibition resulted in the opposite effects. The results from a luciferase reporter assay showed that miR-191 directly targeted the 3'-UTR of theBDNF gene. BDNF knockdown also promoted cell cycle progression to the S phase, cell proliferation and inhibited cell apoptosis, which were consistent with the effects of the miR-191overexpression. A co-transfection experiment showed that BDNF knockdown abolished the effects of miR-191 inhibition. Furthermore, both miR-191 overexpression and BDNFinhibition elevated the phosphorylation of PI3K and AKT, the key components of the PI3K/AKT signaling pathway, whereas BDNFinhibition offset the effects of the miR-191 knockdown. Overall, these data indicated that miR-191 promotes cell proliferation and inhibits apoptosis in porcine immature Sertoli cells by targeting theBDNF gene through activating the PI3K/AKT signaling pathway. This study provides a novel scientific basis for further investigation on the biological functions of miR-191 on porcine spermatogenesis.


Assuntos
MicroRNAs , Fosfatidilinositol 3-Quinases , Animais , Apoptose/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Masculino , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Suínos
7.
Environ Toxicol ; 31(12): 2006-2015, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26434662

RESUMO

Thiamethoxam, a second-generation neonicotinoid insecticide, was found to be toxic to nontarget aquatic organisms. The purpose of this study was to investigate the toxicity of thiamethoxam (0.30, 1.25, and 5.00 mg/L) on zebrafish (Danio rerio) livers at the 7th, 14th, 21st, and 28th days. The reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione-s-transferase (GST), malondialdehyde (MDA) content, and DNA damage were used to evaluate the toxic effects of thiamethoxam on zebrafish. Compared to control groups, ROS levels were ascended in the exposure period; SOD and CAT activities were dramatically increased during early exposure and then inhibited. GST activity only increased on days 28. MDA content was slightly elevated on days 21 and 28. Additionally, a clear dose-response relationship was found for DNA damage. In conclusion, thiamethoxam could induce oxidative stress and DNA damage on the exposed zebrafish. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 2006-2015, 2016.


Assuntos
Antioxidantes/metabolismo , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Oxazinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Tiazóis/toxicidade , Peixe-Zebra/metabolismo , Animais , Catalase/metabolismo , Dano ao DNA , Glutationa Transferase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Malondialdeído/metabolismo , Neonicotinoides , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tiametoxam
9.
J Mater Chem B ; 12(13): 3171-3190, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38488129

RESUMO

Electrospun nanofiber membranes hold great promise as scaffolds for tissue reconstruction, mirroring the natural extracellular matrix (ECM) in their structure. However, their limited bioactive functions have hindered their effectiveness in fostering wound healing. Inorganic nanoparticles possess commendable biocompatibility, which can expedite wound healing; nevertheless, deploying them in the particle form presents challenges associated with removal or collection. To capitalize on the strengths of both components, electrospun organic/inorganic hybrid nanofibers (HNFs) have emerged as a groundbreaking solution for accelerating wound healing and maintaining stability throughout the healing process. In this review, we provide an overview of recent advancements in the utilization of HNFs for wound treatment. The review begins by elucidating various fabrication methods for hybrid nanofibers, encompassing direct electrospinning, coaxial electrospinning, and electrospinning with subsequent loading. These techniques facilitate the construction of micro-nano structures and the controlled release of inorganic ions. Subsequently, we delve into the manifold applications of HNFs in promoting the wound regeneration process. These applications encompass hemostasis, antibacterial properties, anti-inflammatory effects, stimulation of cell proliferation, and facilitation of angiogenesis. Finally, we offer insights into the prospective trends in the utilization of hybrid nanofiber-based wound dressings, charting the path forward in this dynamic field of research.


Assuntos
Nanofibras , Nanofibras/química , Estudos Prospectivos , Cicatrização , Antibacterianos/farmacologia , Bandagens
10.
Artigo em Inglês | MEDLINE | ID: mdl-38946497

RESUMO

Meeting the exacting demands of wound healing encompasses rapid coagulation, superior exudate absorption, high antibacterial efficacy, and imperative support for cell growth. In this study, by emulating the intricate structure of natural skin, we prepare a multifunctional porous bilayer artificial skin to address these critical requirements. The bottom layer, mimicking the dermis, is crafted through freeze-drying a gel network comprising carboxymethyl chitosan (CMCs) and gelatin (GL), while the top layer, emulating the epidermis, is prepared via electrospinning poly(l-lactic acid) (PLLA) nanofibers. With protocatechuic aldehyde and gallium ion complexation (PA@Ga) as cross-linking agents, the bottom PA@Ga-CMCs/GL layer featured an adjustable pore size (78-138 µm), high hemostatic performance (67s), and excellent bacterial inhibition rate (99.9%), complemented by an impressive liquid-absorbing capacity (2000% swelling rate). The top PLLA layer, with dense micronanostructure and hydrophobic properties, worked as a shield to effectively thwarted liquid or bacterial penetration. Furthermore, accelerated wound closure, reduced inflammatory responses, and enhanced formation of hair follicles and blood vessels are achieved by the porous artificial skin covered on the surface of wound. Bilayer artificial skin integrates the advantages of nanofibers and freeze-drying porous materials to effectively replicate the protective properties of the epidermal layer of the skin, as well as the cell migration and tissue regeneration of the dermis. This bioabsorbable artificial skin demonstrates structural and functional comparability to real skin, which would advance the field of wound care through its multifaceted capabilities.

11.
Sci Adv ; 10(20): eado1281, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38748802

RESUMO

The twist engineering of moiré superlattice in van der Waals heterostructures of transition metal dichalcogenides can manipulate valley physics of interlayer excitons (IXs), paving the way for next-generation valleytronic devices. However, the twist angle-dependent control of excitonic potential on valley polarization is not investigated so far in electrically controlled heterostructures and the physical mechanism underneath needs to be explored. Here, we demonstrate the dependence of both polarization switching and degree of valley polarization on the moiré period. We also find the mechanisms to reveal the modulation of twist angle on the exciton potential and the electron-hole exchange interaction, which elucidate the experimentally observed twist angle-dependent valley polarization of IXs. Furthermore, we realize the valley-addressable devices based on polarization switch. Our work demonstrates the manipulation of the valley polarization of IXs by tunning twist angle in electrically controlled heterostructures, which opens an avenue for electrically controlling the valley degrees of freedom in twistronic devices.

12.
Medicine (Baltimore) ; 102(46): e36073, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37986291

RESUMO

To explore the mechanism of Zhenwu Decoction (ZWD) in the treatment of heart failure (HF) by network pharmacology analysis, so as to provide a basis for the innovation and application of drugs. The effective components and targets of 5 Chinese herbal medicines in ZWD were retrieved by TCM Pharmacology Database and Analysis Platform (TCMSP).Gene card, OMIM and TTD databases were used to obtain the disease targets of HF, and the intersection with the targets of ZWD was obtained. We used Cytoscape3.9.1 software to construct a drug-active component-disease-target interaction network for ZWD treatment of HF, and performed protein-protein interaction (PPI) network and topology analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses were performed. Fifty-nine effective components and 229 targets of ZWD were screened. Among them, ZWD for HF has 27 active components and 38 common targets, and the core targets of PPI are IL-6, ATK1 and TNF. Pathway enrichment analysis included lipid and atherosclerotic and TNF signaling pathways. This study preliminarily clarified the main active components, targets and related pathways of ZWD in the treatment of HF, and laid a foundation for further study of the pharmacological effects of ZWD.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Humanos , Farmacologia em Rede , Insuficiência Cardíaca/tratamento farmacológico , Bases de Dados Factuais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa
13.
Nat Commun ; 14(1): 4265, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460549

RESUMO

Single photon emission of quantum emitters (QEs) carrying internal degrees of freedom such as spin and angular momentum plays an important role in quantum optics. Recently, QEs in two-dimensional semiconductors have attracted great interest as promising quantum light sources. However, whether those QEs are characterized by the same valley physics as delocalized valley excitons is still under debate. Moreover, the potential applications of such QEs still need to be explored. Here we show experimental evidence of valley symmetry breaking for neutral QEs in WSe2 monolayer by interacting with chiral plasmonic nanocavities. The anomalous magneto-optical behaviour of the coupled QEs suggests that the polarization state of emitted photon is modulated by the chiral nanocavity instead of the valley-dependent optical selection rules. Calculations of cavity quantum electrodynamics further show the absence of intrinsic valley polarization. The cavity-dependent circularly polarized single-photon output also offers a strategy for future applications in chiral quantum optics.

14.
Nanomaterials (Basel) ; 12(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36364559

RESUMO

Surface-enhanced Raman scattering (SERS) was considered a potential spectroscopic technique for applications of molecular detection and has drawn great research interest during the past decade. So far, fabrications of cost-effective SERS substrates with high sensitivity and stability and the corresponding enhanced mechanisms are always among the list of research topics, although great progress has been made. In this work, Au particles were decorated on Si, ZnO film and ZnO nanorod arrays simultaneously by an economical method of ion sputtering, generating three kinds of SERS substrates for R6G detection. The morphology difference of Au particles on different samples and the consequent influence on Raman scattering were studied. The experiment results exhibited that substrates with Au particles decorated on ZnO nanorods had the highest Raman enhancement factor. Furthermore, multi-effect enhanced mechanisms summarized as localized surface plasmon resonance (LSPR) filed coupling, electron transferring induced by LSPR of Au particles and whispering gallery mode (WGM) effect of the ZnO cavity were presented. This work provides a convenient and efficient method of fabricating SERS substrates and indicates that such proper metal/semiconductor composite structures are promising candidates for SERS applications.

15.
Medicine (Baltimore) ; 101(46): e31778, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401443

RESUMO

Several studies have found associations of genes with atrial fibrillation (AF), including SCN5A-H558R. However, there are limited data of these associations among populations living at different altitudes. We investigated the relationship between the SCN5A-H558R polymorphism and AF in Tibetans living at different altitudes in Qinghai, China. General clinical and genotype data were obtained from 72 patients with AF and 109 non-AF (NAF) individuals at middle altitudes, and from 102 patients with AF and 143 NAF individuals at high altitudes. Multifactor logistic regression was performed to determine associations and AF risk factors. SCN5A-H558R genotypes differed significantly between the AF and NAF groups (P < .0125) and the G allele was an independent AF risk factor (P < .05) at both altitudes, with no significant differences according to altitude (P > .0125). At middle altitudes, age, red blood cell distribution width (RDW-SD), left atrial internal diameter (LAD), and G allele were independent AF risk factors. At high altitudes, age, smoking, hypertension, RDW-SD, free triiodothyronine, LAD, and G allele were independent AF risk factors (P < .05). The G allele of SCN5A-H558R might be an independent risk factor of AF both high and middle altitude, but there are some differences in other clinical risk factors of AF.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/genética , Altitude , Tibet/epidemiologia , Fatores de Risco
16.
Nanoscale ; 14(39): 14537-14543, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36185039

RESUMO

Single charge control of localized excitons (LXs) in two-dimensional transition metal dichalcogenides (TMDCs) is crucial for potential applications in quantum information processing and storage. However, traditional electrostatic doping method by applying metallic gates onto TMDCs may cause inhomogeneous charge distribution, optical quenching, and energy loss. Herein, by locally controlling the ferroelectric polarization of the ferroelectric thin film BiFeO3 (BFO) with a scanning probe, we can deterministically manipulate the doping type of monolayer WSe2 to achieve p-type and n-type doping. This nonvolatile approach can maintain the doping type and hold the localized excitonic charges for a long time without applied voltage. Our work demonstrated that the ferroelectric polarization of BFO can control the charges of LXs effectively. Neutral and charged LXs have been observed in different ferroelectric polarization regions, confirmed by magnetic optical measurement. Highly circular polarization degree with 90% photon emission from these quantum emitters was achieved in high magnetic fields. Controlling the single charge of LXs in a non-volatile way shows a great potential for deterministic photon emission with desired charge states for photonic long-term memory.

17.
J Phys Chem Lett ; 12(8): 2133-2141, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33625855

RESUMO

Two-dimensional (2D) layered hybrid perovskites provide an ideal platform for studying the properties of excitons. Here, we report on a strong triplet-exciton and longitudinal-optical (LO) phonon coupling in 2D (C6H5CH2CH2NH3, PEA)2PbBr4 perovskites. The triplet excitons exhibit strong photoluminescence (PL) in thick perovskite microflakes, and the PL is not detectable for monolayer microflakes. The coupling strength of the triplet exciton-LO phonon is approximately two to three times greater than that of the singlet exciton-LO phonon with a LO phonon energy of about 21 meV. This difference might due to the different locations of singlet excitons located in the well and triplet excitons located in the barrier in the 2D layered perovskite. Revealing the strong coupling of triplet exciton-LO phonon provides a fundamental understanding of many-body interaction in hybrid perovskites, which is useful to develop and optimize the optoelectronic devices based on 2D perovskites in the future.

18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(3): 887-892, 2019 Jun.
Artigo em Zh | MEDLINE | ID: mdl-31204949

RESUMO

OBJECTIVE: To establish the model of antibody-induced immune hemolytic disease in SD rats so as to provide an experimental platform for the exploration of its pathogenesis, course of disease and evaluation of drug efficacy. METHODS: The red blood cells(RBC) of SD rats were isolated and intraperitoneally injected into BALB/c mice to induce production of the antiserum to SD rat RBC. Twenty SD rats were randomly divided into 2 groups. The rats in the model group were injected with 0.1 ml antiserum via tail vein; the rats in the control group were injected with 0.1 ml saline via tail vein.The symptoms of rats, hemolysis-related indexes and histopathological changes of the main organs were observed in both groups after injection. RESULTS: After the injection of antiserum, the SD rats in the model group displayed nasal flaring, laziness, decrease of ingestion and water intake, skin and mucosal jaundice, and gross hemoglobinuria. At the 4th day after the injection, the body weight of SD rats in the model group was significantly lower than that in the control group (P<0.01), and the coefficiens of liver and spleen increased significantly (P<0.01); The levels of WBC, MCV, MCH, DBIL, DBIL/TBIL and FHb all increased statistically significantly, and RBC, Hb, HCT, MCHC and Plt levels decreased significantly in comparison with the control group (P<0.01). In the SD rats of model group, the hemolytic pathological changes were observed in liver, spleen, kidney, lung and small intestine, and erythroid proliferation was observed in bone marrow smears. CONCLUSION: The immune hemolytic disease model of SD rats can be successfully established by injecting the serum aginst SD rat red blood cells into the tail vein of SD rats, showing the high success rate, good reproducibility and low cost.


Assuntos
Hemólise , Fígado , Animais , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
19.
Ying Yong Sheng Tai Xue Bao ; 29(8): 2455-2462, 2018 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30182582

RESUMO

Fire is one of the major factors that alter structure and function of forest in the Great Xing'an Mountains, with consequences on soil carbon cycling in forests. In this study, we collected soil samples (layers O, A, AB, BC, and C) under different fire-severity levels (low, moderate, and high) and post-fire recovery times (1987-2012) in the forests of Great Xing'an Mountains. Analysis of variance and multiple comparison were used to analyze effects of fire severity and reco-very time on content of soil organic carbon. The results showed that soil organic carbon (SOC) content in layer O presented a rising trend under both moderate- and high-severity fire disturbances. The content of SOC in layers A and B decreased year by year under low- and moderate-severity fires, which ranked in the order: 3 years > 5 years > 10 years > over 10 years since fire. The content of SOC under high-severity fire presented an increasing trend within 10 years since fire distur-bance and then decreased rapidly over 10 years. The content of SOC in layer BC presented no obvious changes.


Assuntos
Carbono , Incêndios , Solo/química , Ciclo do Carbono , China , Florestas
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