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1.
Planta ; 260(5): 110, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352582

RESUMO

MAIN CONCLUSION: The GhEB1C gene of the EB1 protein family functions as microtubule end-binding protein and may be involved in the regulation of microtubule-related pathways to enhance resistance to Verticillium wilt. The expression of GhEB1C is induced by SA, also contributing to Verticillium wilt resistance. Cotton, as a crucial cash and oil crop, faces a significant threat from Verticillium wilt, a soil-borne disease induced by Verticillium dahliae, severely impacting cotton growth and development. Investigating genes associated with resistance to Verticillium wilt is paramount. We identified and performed a phylogenetic analysis on members of the EB1 family associated with Verticillium wilt in this work. GhEB1C was discovered by transcriptome screening and was studied for its function in cotton defense against V. dahliae. The RT-qPCR analysis revealed significant expression of the GhEB1C gene in cotton leaves. Subsequent localization analysis using transient expression demonstrated cytoplasmic localization of GhEB1C. VIGS experiments indicated that silencing of the GhEB1C gene significantly increased susceptibility of cotton to V. dahliae. Comparative RNA-seq analysis showed that GhEB1C silenced plants exhibited altered microtubule-associated protein pathways and flavonogen-associated pathways, suggesting a role for GhEB1C in defense mechanisms. Overexpression of tobacco resulted in enhanced resistance to V. dahliae as compared to wild-type plants. Furthermore, our investigation into the relationship between the GhEB1C gene and plant disease resistance hormones salicylic axid (SA) and jasmonic acid (JA) revealed the involvement of GhEB1C in the regulation of the SA pathway. In conclusion, our findings demonstrate that GhEB1C plays a crucial role in conferring immunity to cotton against Verticillium wilt, providing valuable insights for further research on plant adaptability to pathogen invasion.


Assuntos
Resistência à Doença , Gossypium , Filogenia , Doenças das Plantas , Proteínas de Plantas , Gossypium/genética , Gossypium/microbiologia , Gossypium/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Ascomicetos/fisiologia , Ascomicetos/patogenicidade , Ácido Salicílico/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Folhas de Planta/microbiologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Oxilipinas/metabolismo , Verticillium/fisiologia , Ciclopentanos/metabolismo
2.
Anal Chem ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347690

RESUMO

A metasurface as an artificial electromagnetic structure can concentrate optical energy into nanometric volumes to strongly enhance the light-matter interaction, which has been becoming a powerful platform for optical sensing, nonlinear effects, and quantum optics. Herein, we developed a novel hybrid plasmonic-dielectric metasurface consisting of Au nanorings (Au NRs) and TiO2 nanoparticles derived from MXene (TiO2 NPs@MXene). The hybrid metasurface simultaneously benefited from the high near-field enhancement effect of plasmonic materials and the low loss of dielectric materials. Furthermore, the optical modulation efficiency of the hybrid metasurface can be regulated by a magnetic mirror configuration. The magnetic mirror acted like a mirror, confining the electrons to a limited region and increasing the density of the surface plasmon. Moreover, the electrochemiluminescence (ECL) of the Cu2BDC metal-organic framework (Cu2BDC-MOF) served as a light source for the Au NRs/TiO2 NPs@MXene metasurface. Due to the exceptional light manipulation capability of the hybrid metasurface and the coordination of the magnetic mirror, the isotropic ECL signal can be dynamically amplified and converted into polarized emission. Finally, a metasurface-regulated ECL (MECL)-based biosensor with a dual-positive membrane protein recognition strategy was developed for the accurate identification of gastric cancer-derived extracellular vesicles. The novel MECL research opened up a new route in the realization of dynamically tunable metasurfaces for optical sensing and novel nanophotonic devices.

3.
Int J Biol Macromol ; 280(Pt 2): 135720, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299412

RESUMO

Atrazine (ATR), a commonly used herbicide, carries a risk to the health of humans and animals due to its persistence in the environment and accumulation in the body. The main metabolic processes of ATR was occurred in the liver. Therefore, the accumulation of ATR in the body can cause serious hepatic injury. This research aimed to clarify the toxicological effect of ATR and explore the potential protective benefits of selenium-enriched yeast (Yeast-Se) in alleviating liver toxicity induced by ATR. Quails were treated with ATR and Yeast-Se for 28 days. The results indicated that ATR inhibited quail growth and development and caused liver dysfunction. Pathological analysis showed that ATR led to central vein congestion and gallbladder epithelial cells shedding and necrosis. In addition, ATR significantly changed hepatic ion content (Na+, K+, Cl-, Ca2+, Mg2+) and decreased Na+-K+-ATPase and Ca2+/Mg2+-ATPase activities. Notably, supplementary Yeast-Se protects against ATR-induced liver ionic disorder by reversing ATPase activity and increasing ATPase subunits expression. In addition, supplementary Yeast-Se significantly up-regulated the expression of aquaporins (AQPs). In summary, these results indicated that Yeast-Se may regulates AQPs to alleviate ATR-induced ionic homeostasis disturbance in liver.

4.
Biosens Bioelectron ; 264: 116639, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39121617

RESUMO

Tumor-derived extracellular vesicles detection has emerged as an important clinical liquid biopsy approach for cancer diagnosis. In this work, we developed a novel hybrid plasmonic nanocavity consisting of hexagonal Au nanoplates nanoarray, SnS2/Au nanosheet layer and biomimetic lipid bilayer. Firstly, the hybrid plasmonic nanocavity combined the optical confinement for the ECL regulation and the biological recognition for the detection of extracellular vesicles. Secondly, MXene-derived Ti2N QDs have been prepared as ECL nanoprobe to label extracellular vesicles. Moreover, biomimetic lipid bilayer with specific aptamer was used to identify extracellular vesicles and integrate Ti2N QDs into the nanocavity with membrane fusion strategy. Due to the significant electromagnetic field enhancement at the cavity region, the hybrid plasmonic nanocavity provided strong field confinement to concentrate and redistribute the ECL emission of QDs with a 9.3-fold enhancement. The hybrid plasmonic nanocavity-based ECL sensing system improved the spatial controllability of EVs analysis and the accurate resolution of specific protein. It achieved the sensitive detection of extracellular vesicles in ascites and successfully distinguished the peritoneal metastasis of gastric cancer.


Assuntos
Técnicas Biossensoriais , Vesículas Extracelulares , Ouro , Vesículas Extracelulares/química , Humanos , Técnicas Biossensoriais/métodos , Ouro/química , Materiais Biomiméticos/química , Pontos Quânticos/química , Biomimética/métodos , Neoplasias Gástricas/patologia , Bicamadas Lipídicas/química
5.
Materials (Basel) ; 17(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39124471

RESUMO

Changes in temperature, pH, dissolved oxygen content, and nutrients, which are key factors that cause metal corrosion, are common in marine thermoclines. To study the corrosion behaviours and reveal the corrosion mechanisms of metals in a marine thermocline, COMSOL 6.2 software is used in this paper. With this software, the corrosion behaviour of Q345 steel in a thermocline is numerically simulated, and a simulated marine thermocline is built indoors for experimental research purposes. The corrosion behaviour and mechanism of Q345 steel in a marine thermocline were investigated through numerical simulation, electrochemical testing, and corrosion morphology observation. After 21 days of immersion in the simulated marine thermocline, Q345 steel specimens at different depths are shown to have undergone vertical galvanic corrosion, with two anodes and two cathodes. At depths of 70 m and 150 m, the Q345 steel becomes the anode in the galvanic corrosion reaction, while at depths of 110 m and 190 m, the Q345 steel becomes the cathode in the galvanic corrosion reaction. The cathode is protected by the anode and has a relatively low corrosion rate. The main reason underlying these phenomena is that there are large differences in the dissolved oxygen contents and temperatures at different depths in a thermocline. The different dissolved oxygen contents lead to differences in the oxygen concentrations of Q345 steel specimens at various depths. These variations trigger galvanic coupling corrosion. Moreover, the difference in temperature further aggravates the degree of galvanic corrosion.

6.
Talanta ; 279: 126627, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39079436

RESUMO

MiRNA-214 can regulate the expression of their downstream target genes after post-transcriptional and are involved in the biological processes of triple negative breast cancer (TNBC). In this work, the small-sized luminescent Nb2C nanosheet-based whispering gallery mode-enhanced electrochemiluminescence (ECL) strategy was successfully constructed to detect miRNA-214 in TNBC. Firstly, we have synthesized small-sized luminescent Nb2C nanosheets from Nb2AlC MXene. The Nb2C nanosheets not only exhibited more stable chemical properties and reduced the defects of the large sheet structures, but also possessed the quantum confinement effect with the discrete energy level. As a result, the prepared small-sized Nb2C nanosheets had unique luminescent and electrochemical properties. Furthermore, in order to improve the ECL performance of Nb2C nanosheets, SiO2 microspheres were self-assembled on the electrode surface by gas-liquid interface method to form whispering gallery mode structure. Because the light was continuously reflected at the interface of the microcavity in the whispering gallery mode, the ECL signal of Nb2C luminescent nanosheets was amplified largely. Finally, the whispering gallery mode-based ECL sensing platform was established. The results showed that the biosensor had a good linear correlation between the ECL intensity and the logarithm of concentration of miRNA-214 in the range of 10 fM to 100 nM with a limit of detection of 2.5 fM. The actual detection of miRNA-214 content in clinical TNBC tissue samples was realized successfully.


Assuntos
Técnicas Eletroquímicas , Medições Luminescentes , MicroRNAs , Nanoestruturas , MicroRNAs/análise , MicroRNAs/genética , Humanos , Nanoestruturas/química , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Nióbio/química , Limite de Detecção , Luminescência , Neoplasias de Mama Triplo Negativas/genética
7.
Front Plant Sci ; 15: 1400201, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015293

RESUMO

Cotton production faces challenges in fluctuating environmental conditions due to limited genetic variation in cultivated cotton species. To enhance the genetic diversity crucial for this primary fiber crop, it is essential to augment current germplasm resources. High-throughput sequencing has significantly impacted cotton functional genomics, enabling the creation of diverse mutant libraries and the identification of mutant functional genes and new germplasm resources. Artificial mutation, established through physical or chemical methods, stands as a highly efficient strategy to enrich cotton germplasm resources, yielding stable and high-quality raw materials. In this paper, we discuss the good foundation laid by high-throughput sequencing of cotton genome for mutant identification and functional genome, and focus on the construction methods of mutant libraries and diverse sequencing strategies based on mutants. In addition, the important functional genes identified by the cotton mutant library have greatly enriched the germplasm resources and promoted the development of functional genomes. Finally, an innovative strategy for constructing a cotton CRISPR mutant library was proposed, and the possibility of high-throughput screening of cotton mutants based on a UAV phenotyping platform was discussed. The aim of this review was to expand cotton germplasm resources, mine functional genes, and develop adaptable materials in a variety of complex environments.

8.
Anal Chim Acta ; 1312: 342764, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834269

RESUMO

BACKGROUND: Osteopontin (OPN) is closely associated with tumorigenesis, growth, invasion, and immune escape and it serves as a plasma biomarker for hepatocellular carcinoma (HCC). Nevertheless, the accurate and rapid detection of low-abundance OPN still poses significant challenges. Currently, the majority of protein detection methods rely heavily on large precision instruments or involve complex procedures. Therefore, developing a simple, enzyme-free, rapid colorimetric analysis method with high sensitivity is imperative. RESULTS: In this study, we have developed a portable colorimetric biosensor by integrating the triple-helix aptamer probe (THAP) and catalytic hairpin assembly (CHA) strategy, named as T-CHA. After binding to the OPN, the trigger probe can be released from THAP, then initiates the CHA reaction and outputs the signal through the formation of a G-quadruplex/Hemin DNAzyme with horseradish peroxidase-like activity. Consequently, this colorimetric sensor achieves visual free-labeled detection without additional fluorophore modification and allows for accurate quantification by measuring the optical density of the solution at 650 nm. Under optimal conditions, the logarithmic values of various OPN concentrations exhibit satisfactory linearity in the range of 5 pg mL-1 to 5 ng mL-1, with a detection limit of 2.04 pg mL-1. Compared with the widely used ELISA strategy, the proposed T-CHA strategy is rapid (∼105 min), highly sensitive, and cost-effective. SIGNIFICANCE: The T-CHA strategy, leveraging the low background leakage of THAP and the high catalytic efficiency of CHA, has been successfully applied to the detection of OPN in plasma, demonstrating significant promise for the early diagnosis of HCC in point-of-care testing. Given the programmability of DNA and the universality of T-CHA, it can be readily modified for analyzing other useful tumor biomarkers.


Assuntos
Aptâmeros de Nucleotídeos , Colorimetria , Osteopontina , Colorimetria/métodos , Aptâmeros de Nucleotídeos/química , Humanos , Osteopontina/sangue , Osteopontina/química , Osteopontina/análise , Técnicas Biossensoriais/métodos , DNA Catalítico/química , DNA Catalítico/metabolismo , Limite de Detecção , Quadruplex G
9.
Talanta ; 277: 126343, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823325

RESUMO

The van der Waals heterojunction is able to combine the advantages of different materials and has potential to be used in biosensing researches. In this study, we developed a novel van der Waals heterojunction by combining MXene and MoS2 nanosheets for the electrochemiluminescence (ECL) sensing applications. This van der Waals heterojunction material not only possessed the superior conductivity of MXene, but also regulated the electron transport. Additionally, the incorporation of MoS2 nanosheets into the MXene interlayers significantly enhances the material stability. Meanwhile, nitrogen-rich quantum dots (N dots) were synthesized as ECL tags with an impressive nitrogen content of up to 75 %. By integrating the ECL response of N dots within the van der Waals heterojunction, we established a highly efficient sensing system for miRNA-373, which overexpressed in triple negative breast cancer tissues. The van der Waals heterojunction-based biosensor can enhance the ECL signal of N dots effectively to detect miRNA-373 from 1 fM to 1 µM. Consequently, the developed sensing system holds promise for the early detection of metastasis of the triple-negative breast cancer, paving the way for the effective clinical interventions.


Assuntos
Técnicas Biossensoriais , Dissulfetos , Técnicas Eletroquímicas , Medições Luminescentes , Molibdênio , Neoplasias de Mama Triplo Negativas , Molibdênio/química , Dissulfetos/química , Humanos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , MicroRNAs/análise , Pontos Quânticos/química , Nanoestruturas/química
10.
Anal Chim Acta ; 1314: 342792, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876514

RESUMO

Thyroid cancer is the most prevalent endocrine malignancy. The development of sensitive and reliable methods to detect the thyroid cancer is the currently urgent requirement. Herein, we developed an electrochemiluminescence (ECL) biosensor based on MBene derivative quantum dots (MoB QDs) and Ag NP-on-mirror (NPoM) nanocavity structure. On the one hand, MBene QDs as a novel luminescent material in the ECL process was reported for the first time, which can react with H2O2 as co-reactant. On the other hand, the NPoM nanostructure was successfully constructed with the Ag mirror and Ag NPs to provide highly localized hot spots. The NPoM structure had high degree of light field confinement and electromagnetic field enhancement, which can amplify the ECL signal as the signal modulator. Therefore, the synergistic effect of the nanocavity and localized surface plasmon resonance (LSPR) mode in the NPoM facilitated the enhancement of the ECL signal of MoB QDs over 21.7 times. Subsequently, the proposed ECL biosensing system was employed to analyze the expression level of miRNA-222-3p in the thyroid cancer exosome. The results indicated the relative association between miRNA-222-3p and BRAFV600E mutation. The MoB QDs/NPoM biosensor displayed the ideal potential in assessing thyroid cancer progression for advancing clinical diagnosis applications.


Assuntos
Exossomos , MicroRNAs , Pontos Quânticos , Neoplasias da Glândula Tireoide , MicroRNAs/análise , Pontos Quânticos/química , Humanos , Exossomos/química , Neoplasias da Glândula Tireoide/diagnóstico , Medições Luminescentes , Técnicas Eletroquímicas , Técnicas Biossensoriais , Prata/química , Nanopartículas Metálicas/química , Limite de Detecção
11.
Talanta ; 276: 126214, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38718647

RESUMO

In this work, miRNA-10b in the glioblastoma (GBM) tumor tissues has been detected by a novel electrochemiluminescence (ECL) biosensor. Firstly, a new kind of bright luminescent Zn2GeO4:Mn NPs were prepared as ECL nanoprobe, which possessed high fluorescence quantum yield and ECL quantum efficiency. Secondly, Ti3C2 MXene hydrogel (MXG) have been developed as the sensing interface. The MXG retained the inherent biocompatibility and mechanical features of hydrogel. Furthermore, the uniform distribution of metallic Ti3C2 MXene in the hydrogel microstructure provided the good conductivity and multiple binding sites for biomolecules. MXene also can promote the separation of the electrons and holes to accelerate the electron-transfer rate and improve ECL efficiency. Due to these synergistic effects, the screen printed electrode was successfully modified with MXG as sensing platform to enhance the ECL intensity of Zn2GeO4:Mn NP, which greatly improved the detection efficiency and facilitated the high-throughput analysis. Finally, the toehold mediated strand displacement (TMSD) strategy was employed with then biosensor to detect miRNA-10b with the range of 10 fM to 1 nM. The limit of detection was 5 fM. This ECL biosensor has been used to analyze miRNA-10b expression in GBM tumor tissues, which possessed the great potential value for clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Glioblastoma , Hidrogéis , Medições Luminescentes , MicroRNAs , Glioblastoma/diagnóstico , Humanos , Técnicas Biossensoriais/métodos , MicroRNAs/análise , Hidrogéis/química , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Zinco/química , Nanopartículas Metálicas/química , Neoplasias Encefálicas/diagnóstico , Titânio
12.
Food Chem ; 454: 139737, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795622

RESUMO

Atrazine (ATR) is herbicide that causes serious harm to the environment and threatens human food safety. Se-enriched yeast is the best organic selenium source for protecting cells from damage caused by poisonous substances. To explore mechanism of ATR on meat quality degradation and potential protective effects of Se-enriched yeast on ATR-induced muscle injury, quails were treated with ATR and/or Se-enriched yeast for 28 days. The results found ATR disrupted muscle fiber structure and decreased pH, tenderness, water-holding capacity, essential amino acid content and polyunsaturated fatty acid content. ATR aggravated oxidative stress and inflammation by inhibiting Nrf2 pathway and activating NF-κB pathway, ultimately causing apoptosis. However, Se-enriched yeast alleviated ATR-induced alterations in muscle chemical and physical properties by inhibiting oxidative stress and inflammation. Taken together, these results revealed that ATR exposure caused meat quality degradation and Se-enriched yeast had the potential to counteract ATR-induced myotoxicity by inhibiting oxidative stress and inflammation.


Assuntos
Atrazina , Carne , Estresse Oxidativo , Codorniz , Animais , Estresse Oxidativo/efeitos dos fármacos , Carne/análise , Selênio/farmacologia , Herbicidas/farmacologia , Herbicidas/química , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , NF-kappa B/metabolismo , NF-kappa B/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/química , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética
13.
Talanta ; 276: 126289, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776779

RESUMO

Aggregation-induced emission (AIE) has been widely used in research on electrochemiluminescence (ECL) due to its excellent luminescence intensity. In this work, copper superparticles (Cu SPs) were used to construct ECL biosensor to detect the microRNA-103a (miRNA-103a) in triple-negative breast cancer (TNBC) tumor tissues. Firstly, GSH-capped copper clusters were used as precursors to prepare Cu SPs by the AIE effect. Compared with clusters, Cu SPs possessed higher luminescence performance and energy stability, making them an ideal choice for ECL nanoprobe. The film of PVDF-HFP/CeVO4 NPs was constructed and modified with CPBA and GSH as the sensing interface (PCCG). The PCCG film displayed good conductivity and hydrophilicity, and desirable mechanical stability. Moreover, the PCCG film can induce high carrier mobility rates and dissociate large amounts of the co-reactant K2S2O8 to enhance the ECL intensity of Cu SPs. As a result, the prepared ECL sensor with the catalyzed hairpin assembly (CHA) strategy was employed to quantify miRNA-103a in the range of 100 fM to 100 nM. The biosensor provided a novel analytical approach for the clinical diagnosis of TNBC.


Assuntos
Técnicas Biossensoriais , Cobre , MicroRNAs , MicroRNAs/análise , Cobre/química , Humanos , Técnicas Biossensoriais/métodos , Polivinil/química , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Limite de Detecção , Neoplasias de Mama Triplo Negativas/genética
14.
Biosens Bioelectron ; 258: 116356, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705073

RESUMO

In this work, the dual-ligand lanthanide metal-organic framework (MOF)-based electrochemiluminescence (ECL) sensor was constructed for the detection of miRNA-128 in glioblastoma (GBM) diagnosis. The luminescent Eu-MOF (EuBBN) was synthesized with terephthalic acid (BDC) and 2-amino terephthalic acid (BDC-NH2) as dual-ligand. Due to the antenna effect, EuBBN with conjugated-π structure exhibited strong luminescent signal and high quantum efficiency, which can be employed as ECL nanoprobe. Furthermore, the novel plasmonic CuS@Au heterostructure array has been prepared. The localized surface plasmon resonance coupling effect of the CuS@Au heterostructure array can amplify the ECL signal of EuBBN significantly. The EuBBN/CuS@Au heterostructure array-based sensing system has been prepared for the detection of miRNA-128 with a wide linear range from 1 fM to 1 nM and a detection limit of 0.24 fM. Finally, miRNA-128 in the clinic GBM tissue sample has been analysis for the distinguish of tumor grade successfully. The results demonstrated that the dual-ligand MOF/CuS@Au heterostructure array-based ECL sensor can provide important support for the development of GBM diagnosis.


Assuntos
Técnicas Biossensoriais , Európio , Glioblastoma , Ouro , Estruturas Metalorgânicas , MicroRNAs , MicroRNAs/análise , Glioblastoma/diagnóstico , Humanos , Estruturas Metalorgânicas/química , Técnicas Biossensoriais/métodos , Ouro/química , Európio/química , Limite de Detecção , Medições Luminescentes/métodos , Ligantes , Técnicas Eletroquímicas/métodos , Neoplasias Encefálicas/diagnóstico , Ácidos Ftálicos/química , Nanopartículas Metálicas/química , Cobre/química
15.
Nanomicro Lett ; 16(1): 169, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587615

RESUMO

With the continuous advancement of communication technology, the escalating demand for electromagnetic shielding interference (EMI) materials with multifunctional and wideband EMI performance has become urgent. Controlling the electrical and magnetic components and designing the EMI material structure have attracted extensive interest, but remain a huge challenge. Herein, we reported the alternating electromagnetic structure composite films composed of hollow metal-organic frameworks/layered MXene/nanocellulose (HMN) by alternating vacuum-assisted filtration process. The HMN composite films exhibit excellent EMI shielding effectiveness performance in the GHz frequency (66.8 dB at Ka-band) and THz frequency (114.6 dB at 0.1-4.0 THz). Besides, the HMN composite films also exhibit a high reflection loss of 39.7 dB at 0.7 THz with an effective absorption bandwidth up to 2.1 THz. Moreover, HMN composite films show remarkable photothermal conversion performance, which can reach 104.6 °C under 2.0 Sun and 235.4 °C under 0.8 W cm-2, respectively. The unique micro- and macro-structural design structures will absorb more incident electromagnetic waves via interfacial polarization/multiple scattering and produce more heat energy via the local surface plasmon resonance effect. These features make the HMN composite film a promising candidate for advanced EMI devices for future 6G communication and the protection of electronic equipment in cold environments.

16.
Comput Biol Med ; 175: 108492, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678940

RESUMO

Exploring the torque modulation mechanisms of human joints is critical for analyzing the human balance control system and developing natural human-machine interactions for balance support. However, the knee joint is often overlooked in biomechanical models because of its limited range of motion during balance recovery. This poses a challenge in establishing mathematical models for the knee joint's torque modulation mechanisms using computer simulations based on the inverted pendulum model. This study aims to provide a simplified linear feedback model inspired by sensorimotor transformation theory to reveal the torque modulation mechanism of the knee joint. The model was validated using data from experiments involving support-surface translation perturbations. The goodness-of-fit metrics of the model, including R2 values and root mean square errors (RMSE), demonstrated strong explanatory power (R2 ranged from 0.77 to 0.90) and low error (RMSE ranging from 0.035 to 0.072) across different perturbation magnitudes and directions. Through pooling samples across various perturbation conditions and conducting multiple fits, this model revealed that knee torque is modulated using a direction-specific strategy with adaptable feedback gains. These results suggest that the proposed simplified linear model can be used to develop assistive systems and retrieve insights on balance recovery mechanisms.


Assuntos
Articulação do Joelho , Modelos Biológicos , Equilíbrio Postural , Torque , Humanos , Articulação do Joelho/fisiologia , Equilíbrio Postural/fisiologia , Masculino , Adulto , Fenômenos Biomecânicos/fisiologia , Simulação por Computador , Feminino , Adulto Jovem
17.
Anal Chem ; 96(12): 4909-4917, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38489746

RESUMO

Due to the ideal optical manipulation ability, the metasurface has broad prospects in the development of novel optical research. In particular, an active metasurface can control optical response through external stimulus, which has attracted great research interest. However, achieving effective modulation of the optical response is a significant challenge. In this work, we have developed a novel electrochemiluminescence (ECL) signal modulation strategy by an active magnetoplasmonic metasurface under an external magnetic field. The magnetoplasmonic metasurface was assembled based on yolk-shell Fe3O4@Au nanoparticles (Fe3O4@Au YS-NPs). On the one hand, the yolk-shell structure of Fe3O4@Au YS-NPs possessed the surface plasmon coupling effect and cavity-based Purcell effect, which provided high-intensity electromagnetic hot spots in the magnetoplasmonic metasurface. On the other hand, due to the strong magnetic response of the Fe3O4 core, the local magnetic field was induced by the external magnetic field, which further generated Lorentz force acting on the free electrons of Au nanoshells with strong optical anisotropy. The plasmon frequency of the metasurface can be effectively modulated by the Lorentz force effect. As a result, the ECL signal of nitrogen dots (N dots) was dynamically modulated and significantly enhanced at a specific polarization angle by the magnetoplasmonic metasurface under the variable external magnetic field. Based on the luminescence modulation ability and structure feature, the magnetoplasmonic metasurface was further established successfully as a sensing interface for gastric cancer (GC) extracellular vesicle (EV) detection. This study illustrated that the electromagnetic response of the active metasurface can effectively improve the optical modulation ability and luminescence sensing performance.

18.
Phys Med Biol ; 69(8)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38484392

RESUMO

Objective.Monolithic crystal detectors are increasingly being applied in positron emission tomography (PET) devices owing to their excellent depth-of-interaction (DOI) resolution capabilities and high detection efficiency. In this study, we constructed and evaluated a dual-ended readout monolithic crystal detector based on a multiplexing method.Approach.We employed two 12 × 12 silicon photomultiplier (SiPM) arrays for readout, and the signals from the 12 × 12 array were merged into 12 X and 12 Y channels using channel multiplexing. In 2D reconstruction, three methods based on the centre of gravity (COG) were compared, and the concept of thresholds was introduced. Furthermore, a light convolutional neural network (CNN) was employed for testing. To enhance depth localization resolution, we proposed a method by utilizing the mutual information from both ends of the SiPMs. The source width and collimation effect were simulated using GEANT4, and the intrinsic spatial resolution was separated from the measured values.Main results.At an operational voltage of 29 V for the SiPM, an energy resolution of approximately 12.5 % was achieved. By subtracting a 0.8 % threshold from the total energy in every channel, a 2D spatial resolution of approximately 0.90 mm full width at half maximum (FWHM) can be obtained. Furthermore, a higher level of resolution, approximately 0.80 mm FWHM, was achieved using a CNN, with some alleviation of edge effects. With the proposed DOI method, a significant 1.36 mm FWHM average DOI resolution can be achieved. Additionally, it was found that polishing and black coating on the crystal surface yielded smaller edge effects compared to a rough surface with a black coating.Significance.The introduction of a threshold in COG method and a dual-ended readout scheme can lead to excellent spatial resolution for monolithic crystal detectors, which can help to develop PET systems with both high sensitivity and high spatial resolution.


Assuntos
Redes Neurais de Computação , Tomografia por Emissão de Pósitrons , Tomografia por Emissão de Pósitrons/métodos , Fótons , Gravitação
19.
Anal Chim Acta ; 1301: 342488, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38553118

RESUMO

Gastric cancer (GC) was one of the most common cancers with high mortality. The detection of GC peritoneal metastasis had important significance. In this work, we have developed the novel electrochemiluminescence (ECL) biosensor to detect microRNA in GC extracellular vesicle (EV). Firstly, in situ growth of Cu nanocluster (Cu NC) on the metal-organic frameworks (MOFs) nanosheet was achieved successfully. Due to the confinement effect, Cu NCs in the porous structure of Zn MOF possessed the high quantum yield and good stability. Meanwhile, Zn MOF provided good electrochemical activity for the ECL reaction. Furthermore, the nanosized MOFs did not only act as sensing platform to load Cu NCs and link biomolecules, but also reduce steric hindrance effect for biomolecular recognition. Additionally, Au NPs/MXene and phospholipid layer were prepared and modified on the electrode, which can regulate electron transfer and improve the target recognition efficiency. The Cu NCs/Zn MOF nanosheet-based ECL sensor was employed to detect miRNA-421 from 1 fM to 1 nM with a detection limit of 0.5 fM. Finally, extracellular vesicles form clinic GC patient ascites were extracted and analyzed. The results showed that the constructed biosensor can be used for the GC peritoneal metastasis diagnosis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , MicroRNAs , Neoplasias Peritoneais , Humanos , Estruturas Metalorgânicas/química , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Nanopartículas Metálicas/química
20.
Plant Cell Rep ; 43(3): 83, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441719

RESUMO

KEY MESSAGE: The transcription factor AmCBF1 deepens the leaf colour of transgenic cotton by binding to the promoter of the chloroplast development-related protein GhClpR1 to promote photosynthesis. The ATP-dependent caseinolytic protease (Clp protease) family plays a crucial role within chloroplasts, comprising several Clp proteins to maintain chloroplast homeostasis. At present, research on Clp proteins mainly focuses on Arabidopsis, leaving its function in other plants, particularly in crops, less explored. In this study, we overexpressed AmCBF1 from Ammopiptanthus mongolicus (A. mongolicus) in wild type (R15), and found a significant darkening of leaf colour in transgenic plants (L28 and L30). RNA-seq analysis showed an enrichment of pathways associated with photosynthesis. Subsequent screening of differentially expressed genes revealed a significant up-regulation of GhClpR1, a gene linked to chloroplast development, in the transgenic strain. In addition, GhClpR1 was consistently expressed in upland cotton, with the highest expression observed in leaves. Subcellular localization analysis revealed that the protein encoded by GhClpR1 was located in chloroplasts. Yeast one hybrid and dual luciferase experiments showed that the AmCBF1 transcription factor positively regulates the expression of GhClpR1. VIGs-mediated silencing of GhClpR1 led to a significant yellowing phenotype in the leaves. This was accompanied by a reduction in chlorophyll content, and microscopic examination of chloroplast ultrastructure revealed severe developmental impairment. Finally, yeast two-hybrid assays showed that GhClpR1 interacts with the Clp protease complex accessory protein GhClpT2. Our study provides a foundation for studying the function of the Clp protease complex and a new strategy for cultivating high-light-efficiency cotton resources.


Assuntos
Arabidopsis , Gossypium , Gossypium/genética , Endopeptidase Clp/genética , Cloroplastos , Fotossíntese , Arabidopsis/genética , Fatores de Transcrição/genética
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