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1.
Sensors (Basel) ; 22(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36236722

RESUMO

Model assisted probability of detection (MAPoD) is crucial for quantifying the inspection capability of a nondestructive testing (NDT) system which uses the coil or probe to sense the size and location of the cracks. Unfortunately, it may be computationally intensive for the simulation models. To improve the efficiency of the MAPoD, in this article, an efficient 3D eddy current nondestructive evaluation (ECNDE) forward solver is proposed to make estimations for PoD study. It is the first time that singular value decomposition (SVD) is used as the recompression technique to improve the overall performance of the adaptive cross approximation (ACA) algorithm-based boundary element method (BEM) ECNDE forward solver for implementation of PoD. Both the robustness and efficiency of the proposed solver are demonstrated and testified by comparing the predicted impedance variations of the coil with analytical, semi-analytical and experimental benchmarks. Calculation of PoD curves assisted by the proposed simulation model is performed on a finite thickness plate with a rectangular surface flaw. The features, which are the maximum impedance variations of the coil for various flaw lengths, are obtained entirely by the proposed model with selection of the liftoff distance as the uncertain parameter in a Gaussian distribution. The results show that the proposed ACA-SVD based BEM fast ECNDE forward solver is an excellent simulation model to make estimations for MAPoD study.

2.
Opt Express ; 29(22): 35938-35950, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34809017

RESUMO

In this work, an ultrawideband and high-efficient polarization conversion metasurface (PCM) is proposed, which can efficiently convert linearly polarized waves into cross-polarized waves in an ultra-wide frequency range. The unit cell of the proposed PCM is composed of two pairs of L-shaped metallic patches covered by a dielectric superstrate and an air-based substrate attached with a metallic ground. The PCM has an operating band from 3.37 to 22.07 GHz with the polarization conversion ratio (PCR) over 90% under the normal incidence, which the ratio bandwidth (fH/fL) is 6.5:1. The PCR can achieve 100% at seven resonant frequencies. The equivalent circuit model is analyzed to explain the fundamental cause of the PCM's multi-resonance and polarization conversion behaviors. In addition, all possible near-field interactions among the resonator, the superstrate, and the ground sheet can be accurately calculated using interference theory, which reveals the underlying physical mechanisms of the multi-resonance metasurface. The theoretical calculated, numerically simulated, and measured results are in good agreement. Compared to other PCMs, the proposed PCM has a simple geometry structure but an ultrawideband and high PCR property.

3.
Philos Trans A Math Phys Eng Sci ; 378(2182): 20190583, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32921240

RESUMO

The eddy current non-destructive evaluation (NDE) modelling using Stratton-Chu formulation-based fast algorithm is analysed. Stratton-Chu formulations, which have no low frequency breakdown issue, are selected for modelling electromagnetic NDE problems with low frequency and high conductivity approximations. As the main contribution of this article, the robustness and efficiency of the approximations, which result in big savings in both memory and CPU time, are validated and analysed using examples from practical EC testing. The boundary element method (BEM) is used to discretize the integral equations into a linear system of equations: the first order Rao-Wilton-Glisson (RWG) vector basis functions with the flat triangle meshes of the object and pulse basis functions are selected to expand the equivalent surface currents and the normal component of magnetic fields, respectively. Then the multilevel adaptive cross approximation (MLACA) algorithm is applied to accelerate the iterative solution process. The performance and efficiency of adaptively applying a multi-stage (level) algorithm based on the criteria concluded for the operators are shown. This article is part of the theme issue 'Advanced electromagnetic non-destructive evaluation and smart monitoring'.

4.
Mikrochim Acta ; 187(2): 136, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953607

RESUMO

A two-dimensional zinc(II)-based metal-organic framework [Zn • (BA) • (BBI)] was synthesized from 1,2-benzenediacetic acid and 1,1'-(1,4-butanediyl) bis(imidazole) via a solvothermal reaction. The crystal exhibits good chemical stability in the pH range from 2 to 12, and strong fluorescence with excitation/emission maxima of 270/290 nm. The crystal is shown to by a viable fluorescent probe for the detection of ascorbic acid (AA) and the antibiotics chloramphenicol (CHL) and ceftriaxone (CRO). Fluorescence intensity of crystal dispersion is significantly quenched with increasing concentrations of AA/CHL/CRO. Quenching occurs even in the presence of other substances. The assay is fast (5 s) and has a low detection limit (1.6 ppb for AA, 12 ppb for CHL and 3.9 ppb for CRO). The crystal still has a good quenching effect on AA/CHL/CRO after washing and using for five times. The response of the probe is related to the interplay between the MOF and analytes via energy absorption competition. Graphical abstractSchematic diagram of preparing Zn • (BA) • (BBI) and responding to target analytes. BA: 1,2-phenyldiacetic acid; BBI: 1,1'-(1,4-butanediyl)bis(imidazole); Zn • (BA) • (BBI): Crystal chemical formula.


Assuntos
Ácido Ascórbico/sangue , Ceftriaxona/sangue , Cloranfenicol/sangue , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Animais , Antibacterianos/sangue , Cabras , Limite de Detecção , Espectrometria de Fluorescência/métodos , Zinco/química
5.
Microb Pathog ; 127: 267-276, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30550842

RESUMO

Copper oxide nanoparticles (CuO NPs) were synthesized biologically using leaf extract of Camilla japonica. The typical UV-visible spectral peak of CuO NPs was observed at a wavelength of ∼290 nm, which confirmed their successful synthesis. From scanning electron microscope (SEM) and transmission electron microscope (TEM) analyses, the synthesized CuO NPs were found to possess spherical shape. Energy dispersive X-ray analyzer (EDX) results revealed that the CuO NPs are almost pure with atomic percentages of 50.92 for Cu and 49.08 for O. Fourier transform infrared (FTIR) confirmed the presence of an absorption peak located at a wavenumber position of ∼480 cm-1 typical for highly pure CuO NPs. TEM images displayed that the particles are relatively uniform in size ∼15-25 nm. The P. aeruginosa and K. pneumonia showed complete resistance against Hexa 077 antibiotic discs. The result of ≤22 ceftazidime and ≤27 cefotaxime confirmed that both the uropathogens were ESBL producers. The ≥8 mm of the MIC stripe further confirmed that both the uropathogens were ESBL producers. Furthermore, the antibacterial activity of CuO NPs against selected ESBL producing P. aeruginosa and K. pneumoniae at minimum inhibition concentration (MIC) of 100 µg/mL. The decreased cell viability and damaged membrane construction of both the uropathogens were observed by confocal laser scanning microscope (CLSM) using AO/EB stains at desired MIC dose. The morphological damage of the bacterial cells was demonstrated by SEM analysis. Hence, based on the above in vitro findings, the results suggested that the CuO NPs are efficient antibacterial compounds against ESBL producing bacteria, and that the plant leaf mediated CuO NPs can be considered as novel and promising material to act against various infectious bacteria.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Cobre/metabolismo , Cobre/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Pseudomonas aeruginosa/efeitos dos fármacos , Camellia/química , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Klebsiella pneumoniae/enzimologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Pseudomonas aeruginosa/enzimologia , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Lactamases/metabolismo
6.
Analyst ; 144(8): 2656-2661, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30843538

RESUMO

Recently, the pollution and damage caused by antibiotics in water have aroused serious concerns. In this situation, it is extremely important to develop a highly effective approach to detect antibiotics in water. In this contribution, we built a Cd-MOF material with stable fluorescence properties, using bbi = 1,4-bis(2-methyl-imidazol-1-yl)butane and H2L = 1,2-phenylenediacetic acid as organic ligands and Cd(NO3)2·4H2O as the metal node. The highly selective response of this MOF probe to ceftriaxone sodium (an antibiotic) can reach up to the ppb level in water, along with a fast response time, acid and alkali resistance, and anti-interference ability.


Assuntos
Antibacterianos/análise , Cádmio/química , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Fluorescência , Corantes Fluorescentes/síntese química , Ligantes , Limite de Detecção , Estruturas Metalorgânicas/síntese química , Espectrometria de Fluorescência/métodos , Água/química
7.
Microb Pathog ; 121: 224-231, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29807135

RESUMO

The accelerative outgrowth of extended spectrum ß-lactamases (ESBLs) producing Escherichia coli (E. coli) and Proteus mirabilis (P. mirabilis) was mainly due to incessant relentless influence of antibiotics thereby increasing incidence and death rate which was obvious from the survey of ESBLs producing bacteria related health problem. In the present paper, we synthesized and characterized zinc oxide nanoparticles (ZnO NPs) employing using Camellia japonica leaf extract, bactericidal action of these NPs against extended spectrum ß lactamases (ESBLs) positive E. coli and P. mirabilis clinical strains owing the minimal inhibitory concentration (MIC) percentage 83, 81% at 100 µg/mL concentration and minimum bactericidal concentration (MBC) final inhibiting concentration at 150 µg/mL. Moreover, confocal laser scanning microscopy (CLSM) and scanning electron microscope (SEM) results evident for loss of viability, cell shrinkage, disarrangement of cell membrane, and cell wall lysis activity of ZnO NPs against ESBLs positive E. coli BDUMS3 (KY617770) and P. mirabilis BDUMS1 (KY617768) strains. From the results, it was observed that the biologically synthesized ZnO NPs has stronger antibacterial effect against ESBLs producing bacterial strains. Nevertheless, current date there is no reports of antibacterial activity of metal oxide (ZnO) NPs against ESBL producing gram negative bacteria. Consequently, this finding is the first report in this respect and it shows band gap energy and ROS accumulation to damage the cell wall and inhibit the growth of ESBL producing gram negative strains.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Nanopartículas/química , Óxido de Zinco/farmacologia , beta-Lactamases/metabolismo , Camellia/química , Parede Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Extratos Vegetais/farmacologia , Folhas de Planta/química , Proteus mirabilis/efeitos dos fármacos
8.
Can Vet J ; 59(7): 779-782, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30026627

RESUMO

This retrospective analysis aimed to determine the effects of a maternal viral vaccination program (MVVP; Express Verified) on calf health during the feeding period. In low- and high-risk populations, calves born to dams vaccinated pre-breeding with program products had improved morbidity and mortality outcomes compared with non-program animals.


Analyse rétrospective de la morbidité dans des parcs d'engraissement et résultats de mortalité chez les veaux nés de mères ayant des antécédents de vaccination connus. Cette analyse rétrospective visait à déterminer les effets d'un programme maternel de vaccination virale (PMVV; Express Verified) sur la santé des veaux durant la période d'allaitement. Dans les populations à risque faible et élevé, les veaux nés de mères vaccinées avant l'accouplement avec des produits de programme présentaient des résultats améliorés de morbidité et de mortalité comparativement aux animaux à l'extérieur du programme.(Traduit par Isabelle Vallières).


Assuntos
Complexo Respiratório Bovino/mortalidade , Doenças dos Bovinos/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Complexo Respiratório Bovino/epidemiologia , Bovinos , Doenças dos Bovinos/imunologia , Feminino , Febre/epidemiologia , Febre/veterinária , Masculino , Estudos Retrospectivos
9.
Mikrochim Acta ; 185(1): 52, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29594564

RESUMO

A film of perovskite-type LaFeO3 nanoparticles (NPs) was deposited on fluorine-doped tin oxide (FTO) conducting glass via dipping-lifting and calcination. Scanning electron microscopy shows that the NPs are evenly distributed on the surface of the glass. The modified glass was further coated with antibody against human interleukin 6 (IL-6) to result in a photoelectrochemical immunosensor for IL-6. The well-established photoelectrochemical immunoassay has a linear current response in the range of 0.1 pg·mL-1 to 0.1 µg·mL-1 and a detection limit as low as 33 fg·mL-1. Graphical abstract Schematic of a novel photoelectochemical immunoassay for the measurement of IL-6 based on perovskite-type LaFeO3 nanoparticles. The immunoassay had a higher sensitivity and may also be applied to other bioanalysis and environment monitoring.


Assuntos
Imunoensaio/métodos , Interleucina-6/análise , Anticorpos , Compostos de Cálcio , Técnicas Eletroquímicas , Flúor , Humanos , Imunoensaio/normas , Interleucina-6/imunologia , Limite de Detecção , Óxidos/química , Processos Fotoquímicos , Compostos de Estanho , Titânio
10.
Nanotechnology ; 27(14): 145701, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26903086

RESUMO

P-nitrophenol (4-NP) and hydrazine hydrate are considered to be highly toxic pollutants in wastewater, and it is of great importance to remove them. Herein, TiO2-loaded Co0.85Se thin films with heterostructure were successfully synthesized by a hydrothermal route. The as-synthesized samples were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, transmission electron microscopy and selective-area electron diffraction. The results demonstrate that TiO2 nanoparticles with a size of about 10 nm are easily loaded on the surface of graphene-like Co0.85Se nanofilms, and the NH3 · H2O plays an important role in the generation and crystallization of TiO2 nanoparticles. Brunauer-Emmett-Teller measurement shows that the obtained nanocomposites have a larger specific surface area (199.3 m(2) g(-1)) than that of Co0.85Se nanofilms (55.17 m(2) g(-1)) and TiO2 nanoparticles (19.49 m(2) g(-1)). The catalytic tests indicate Co0.85Se-TiO2 nanofilms have the highest activity for 4-NP reduction and hydrazine hydrate decomposition within 10 min and 8 min, respectively, compared with the corresponding precursor Co0.85Se nanofilms and TiO2 nanoparticles. The enhanced catalytic performance can be attributed to the larger specific surface area and higher rate of interfacial charge transfer in the heterojunction than that of the single components. In addition, recycling tests show that the as-synthesized sample presents stable conversion efficiency for 4-NP reduction.

11.
Phys Chem Chem Phys ; 17(41): 27548-57, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26427022

RESUMO

A facile one-step method for the synthesis of a water-soluble selenium/polypyrrole (Se/PPy) nanocomposite was developed. In the aqueous synthesis process, the pyrrole acted as a reductant for the reduction of H2SeO3, and then the elemental Se formed in situ acted as a catalyst for the polymerization of pyrrole. The characterization results show that the as-obtained composite (Se/PPy) is a spherical (Φ80 nm) product that is made up of amorphous Se particles coated by PPy layers. The formation mechanism and influence factors of the products were discussed, based on a series of experiments. It is proposed that remainder H2SeO3 adsorbed on the PPy chains increased the water-solubility and conductivity of the Se/PPy nanocomposite. Significantly, relying on the synergistic effect of photo-conductive Se nanoparticles and electric-conductive PPy molecules, the Se/PPy nanocomposite possesses a large two-photon absorption (2PA) cross-section and good optical limiting properties, which were demonstrated by the Z-scan technique using a femtosecond laser. We believe that this work should be an interesting strategy for developing polymer composites with excellent optoelectrical properties.


Assuntos
Nanocompostos/química , Polímeros/química , Pirróis/química , Selênio/química , Água/química , Catálise , Fenômenos Ópticos , Tamanho da Partícula , Polimerização , Solubilidade , Propriedades de Superfície
12.
Small ; 10(4): 717-24, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23929765

RESUMO

A new kind of multifunctional Co0.85 Se-Fe3 O4 nanocomposites is synthesized by loading Fe3 O4 nanoparticles (NPs) with a size of about 5 nm on the surface of Co0.85 Se nanosheets under hydrothermal conditions without using any surfactant or structure-directing agents. The Co0.85 Se-Fe3 O4 nanocomposite exhibits remarkable catalytic performance for hydrogenation of p-nitrophenol (4-NP) at room temperature and good adsorption behavior for methylene blue trihydrate in water. This nanocomposite also shows a high specific surface area and magnetic separation capability for recyclable utilization. The enhanced performances both in catalysis and adsorption are better than either individual component of Co0.85 Se nanosheets or Fe3 O4 nanoparticles, demonstrating the possibility for designing new multifunctional nanocomposites with improved performances for catalysis, adsorbents, and other applications.

13.
Animals (Basel) ; 14(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612279

RESUMO

Digital dermatitis (DD) is an emerging disease in feedlot cattle. Our objective was to identify animal- and feedlot-level risk factors for DD by analyzing individual animal health records (n = 1,209,883) and feedlot-level records from western Canadian feedlots (n = 28) between 2014 and 2018, inclusive. The risk of a DD diagnosis was higher (incidence rate ratio (IRR) = 2.08, 95% CI 1.52 to 2.86) in cattle sourced from confined background operations (CB) versus cattle sourced from auction markets (AM). Conversely, ranch direct (RD) cattle were (IRR = 0.02, 95% CI 0.04 to 0.30) lower risk than AM cattle of being diagnosed with DD. The risk of being diagnosed with DD was higher in females than in males. The magnitude of the risk in females over males was influenced by annual DD incidence in low morbidity years (2014, 2017, and 2018) (IRR = 2.02, 95% CI 1.27 to 3.19), medium morbidity years (2016) (IRR = 2.95, 95% CI 1.64 to 5.33), and high morbidity years (2015) (IRR = 5.41, 95% CI 3.27 to 8.95). At the feedlot-level, the risk of a diagnosis of DD was lower in small capacity (SCF) versus large capacity feedlots (LCF) (IRR = 0.24, 95% CI 0.05 to 0.76). Future research should focus on identifying factors that may propagate disease transmission between cattle of different sexes and from different acquisition sources.

14.
J Nanosci Nanotechnol ; 13(8): 5726-31, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882825

RESUMO

A rapid chemical method has been developed for the synthesis of the CdTe nanoribbons with cubic crystalline phase. The method is based on the template-engaged synthesis in which the Te nanowires were used as template reagents. On the basis of a series of experiments and characterizations, the electrochemical property of CdTe nanoribbons was determined by the voltammetric technique. Furthermore, electrochemiluminescence property of CdTe nanoribbons was investigated. The results show that CdTe nanoribbons are helpful to obtain stable electrochemiluminescence emission for 1200 seconds.

15.
Genes (Basel) ; 14(4)2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37107628

RESUMO

The SHORT INTERNODES (SHI)-related sequences (SRS) are plant-specific transcription factors that have been quantitatively characterized during plant growth, regeneration, and stress responses. However, the genome-wide discovery of SRS family genes and their involvement in abiotic stress-related activities in cassava have not been documented. A genome-wide search strategy was used to identify eight family members of the SRS gene family in cassava (Manihot esculenta Crantz). Based on their evolutionary linkages, all MeSRS genes featured homologous RING-like zinc finger and IXGH domains. Genetic architecture and conserved motif analysis validated the categorization of MeSRS genes into four groups. Eight pairs of segmental duplications were detected, resulting in an increase in the number of MeSRS genes. Orthologous studies of SRS genes among cassava and three different plant species (Arabidopsis thaliana, Oryza sativa, and Populus trichocarpa) provided important insights into the probable history of the MeSRS gene family. The functionality of MeSRS genes was elucidated through the prediction of protein-protein interaction networks and cis-acting domains. RNA-seq data demonstrated tissue/organ expression selectivity and preference of the MeSRS genes. Furthermore, qRT-PCR investigation of MeSRS gene expression after exposure to salicylic acid (SA) and methyl jasmonate (MeJA) hormone treatments, as well as salt (NaCl) and osmotic (polyethylene glycol, PEG) stresses, showed their stress-responsive patterns. This genome-wide characterization and identification of the evolutionary relationships and expression profiles of the cassava MeSRS family genes will be helpful for further research into this gene family and its function in stress response. It may also assist future agricultural efforts to increase the stress tolerance of cassava.


Assuntos
Arabidopsis , Manihot , Manihot/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Genoma de Planta , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Cloreto de Sódio/metabolismo , Arabidopsis/genética
16.
Polymers (Basel) ; 15(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38006076

RESUMO

Coil-rod copolymers with a dendritic polyethylene (DPE) core and multiple helical poly(γ-benzyl-L-glutamate) (PBLG) arms (DPE-(PBLG)n) were prepared by palladium-catalyzed copolymerization in tandem with ring-opening polymerization (ROP). Macroinitiator (DPE-(NH2)11) was firstly prepared by the group transformation of DPE-(OH)11 generated from palladium-catalyzed copolymerization of ethylene and acrylate comonomer. Coil-helical DPE-(PBLG)11 copolymers were prepared by ROP of γ-benzyl-L-glutamate-N-carboxyanhydride (BLG-NCA). These DPE-(PBLG)11 copolymers could form thermoreversible gels in toluene solvent, and the dendritic topology of the DPE core increased the critical gelation concentrations. The self-assembled nanostructure of gels was fully characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), and wide-angle X-ray diffraction (WAXD), and the morphology of the fibrous structure was a twisted flat ribbon through a self-assembled nanoribbon mechanism. The self-assembled fibers formed by DPE-(PBLG45)11 are more heterogeneous and ramified than previously observed fibers formed by PBLG homopolymer and block copolymers.

17.
PLoS One ; 18(4): e0282100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37079564

RESUMO

The Arabidopsis thaliana ASYMMETRIC LEAVES2 (AS2) gene is responsible for the development of flat, symmetric, and extended leaf laminae and their veins. The AS2 gene belongs to the plant-specific AS2-LIKE/LATERAL ORGAN BOUNDARIES (LOB)-domain (ASL/LBD), which consists of 42 proteins in Arabidopsis with a conserved amino-terminal domain known as the AS2/LOB domain, and a variable carboxyl-terminal region. AS2/LOB domain consists of an amino-terminal (N-terminal) that contains a cysteine repeat (the C-motif), a conserved glycine residue, and a leucine-zipper-like. AS2/LOB domain has been characterised in plants such as A. thaliana, Zea mays, and Oryza sativum. Nevertheless, it remains uncharacterised in cassava (Manihot esculenta). Characterisation and identification of cassava ASL/LBD genes using the computational algorithms, hidden Markov model profiles (PF03195), determined 55 ASL/LBD genes (MeASLBD1 to MeASLBD55). The gene structure and motif composition were conserved in MeASLBDs, while the expression profiles of these genes were highly diverse, implying that they are associated with diverse functions. Weighted gene co-expression network analysis (WGCNA) of target genes and promoter analysis suggest that these MeASLBDs may be involved in hormone and stress responses. Furthermore, the analysis of cis-regulatory elements in promoter regions suggested that MeASLBDs may be involved in the plant phytohormone signal response. The transcriptome data of cassava under biotic and abiotic stresses revealed that MeASLBD46 and MeASLBD47 greatly respond to disease and drought. The MeASLBD47 gene was selected for functional analysis. The result indicated that MeASLBD47 significantly mitigated the virulence of cassava bacterial blight (XamCHN11) through Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) and Virus-induced gene silencing (VIGS). These findings provided a comprehensive analysis of ASL/LBD genes and laid the groundwork for future research to understand ASL/LBD genes.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Manihot , Manihot/genética , Manihot/metabolismo , Estudo de Associação Genômica Ampla , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas
18.
Research (Wash D C) ; 6: 0123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287891

RESUMO

Seeking new strategies to tune the intrinsic defect and optimize the thermoelectric performance via no or less use of external doped elements (i.e., plain optimization) is an important method to realize the sustainable development of thermoelectric materials. Meanwhile, creating dislocation defects in oxide systems is quite challenging because the rigid and stiff ionic/covalent bonds can hardly tolerate the large strain energy associated with dislocations. Herein, taking BiCuSeO oxide as an example, the present work reports a successful construction of dense lattice dislocations in BiCuSeO by self-doping of Se at the O site (i.e., SeO self-substitution), and achieves plain optimization of the thermoelectric properties with only external Pb doping. Owing to the self-substitution-induced large lattice distortion and the potential reinforcement effect by Pb doping, high-density (about 3.0 × 1014 m-2) dislocations form in the grains, which enhances the scattering strength of mid-frequency phonon and results in a substantial low lattice thermal conductivity of 0.38 W m-1 K-1 at 823 K in Pb-doped BiCuSeO. Meanwhile, PbBi doping and Cu vacancy markedly improve the electrical conductivity while maintaining a competitively high Seebeck coefficient, thereby contributing to a highest power factor of 942 µW m-1 K-2. Finally, a remarkably enhanced zT value of 1.32 is obtained at 823 K in Bi0.94Pb0.06Cu0.97Se1.05O0.95 with almost compositional plainification. The high-density dislocation structure reported in this work will also provide a good inspiration for the design and construction of dislocations in other oxide systems.

19.
J Nanosci Nanotechnol ; 12(10): 7980-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23421167

RESUMO

Direct electrochemistry of hemoglobin (Hb) was successfully fabricated by immobilizing Hb on the nanocomposites containing of Ag@C nanocables and Au nanoparticles (AuNPs) modified glassy carbon electrode (GCE). The immobilized Hb retained its biological activity and shown high catalytic activities to the reduction of H2O2 by circular dicroism (CD) spectrum, fourier transform infrared (FT-IR) spectrum and cyclic voltammetry (CV). Experimental conditions such as scan rate and pH Value were studied and optimized. The results indicated that the resulting biosensor are linear to the concentrations of H2O2 in the ranges of 6.67 x 10(-7)-2.40 x 10(5) M, and the detection limit is 2.02 x 10(-7) M. The electrochemical biosensor has also high stability and good reproducibility.


Assuntos
Eletroquímica/métodos , Ouro/química , Hemoglobinas/química , Nanopartículas Metálicas , Catálise , Dicroísmo Circular , Peróxido de Hidrogênio/química , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
20.
ACS Appl Mater Interfaces ; 14(18): 20972-20980, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35485843

RESUMO

Recently, ternary Cu-based Cu-IV-Se (IV = Sb, Ge, and Sn) compounds have received extensive attention in the thermoelectric field. Compared with Cu-Sb-Se and Cu-Sn-Se, Cu-Ge-Se compounds have been less studied due to its poor Seebeck coefficient and high thermal conductivity. Here, the Cu2GeSe3 material with high electrical conductivity was first prepared, and then, its effective mass was increased by doping with S, which led to the Seebeck coefficient of the doped sample being 1.93 times higher than that of pristine Cu2GeSe3 at room temperature. Moreover, alloying Ag at the Cu site in the Cu2GeSe2.96S0.04 sample could further cause a 5.16 times increase in the Seebeck coefficient at room temperature, and the lattice thermal conductivity was remarkably decreased because of the introduction of the dislocations in the Cu2GeSe3 sample. Finally, benefitted from the high Seebeck coefficient and low thermal conductivity, a record high ZT = 0.9 at 723 K was obtained for the Cu1.85Ag0.15GeSe2.96S0.04 sample, which increased 345% in comparison with the pristine Cu2GeSe3, and it is among the highest reported values for Cu2GeSe3-based thermoelectric.

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