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1.
Environ Res ; 258: 119204, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38802033

RESUMO

This study synthesized zinc oxide nanoparticles (ZnO NPs) using a novel green approach, with Sida acuta leaf extract as a capping and reducing agent to initiate nucleation and structure formation. The innovation of this study lies in demonstrating the originality of utilizing zinc oxide nanoparticles for antibacterial action, antioxidant potential, and catalytic degradation of Congo red dye. This unique approach harnesses eco-friendly methods to initiate nucleation and structure formation. The synthesized nanoparticles' structure and conformation were characterized using UV-vis (λmax = 280 nm), X-ray, atomic force microscopy, SEM, HR-TEM and FTIR. The antibacterial activity of the Nps was tested against Pseudomonas sp, Klebsiella sp, Staphylococcus aureus, and E. coli, demonstrating efficacy. The nanoparticles exhibited unique properties, with a crystallite size of 20 nm (XRD), a surface roughness of 2.5 nm (AFM), and a specific surface area of 60 m2/g (SEM). A Convolutional Neural Network (CNN) was effectively employed to accurately classify and analyze microscopic images of green-synthesized zinc oxide nanoparticles. This research revealed their exceptional antioxidant potential, with an average DPPH scavenging rate of 80% at a concentration of 0.05 mg/mL. Additionally, zeta potential measurements indicated a stable net negative surface charge of approximately -12.2 mV. These quantitative findings highlight the promising applications of green-synthesized ZnO NPs in healthcare, materials science, and environmental remediation. The ZnO nanoparticles exhibited catalytic capabilities for dye degradation, and the degradation rate was determined using UV spectroscopy. Key findings of the study encompass the green synthesis of versatile zinc oxide nanoparticles, demonstrating potent antibacterial action, antioxidant capabilities, and catalytic dye degradation potential. These nanoparticles offer multifaceted solutions with minimal environmental impact, addressing challenges in various fields, from healthcare to environmental remediation.

2.
Environ Res ; 249: 117464, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37980983

RESUMO

Zinc oxide nanoparticles (ZnO) possess unique features that mak them a common matter among different industries. Nevertheless, traditional models of synthesizing ZnO-NPs are related with health and environmental and risks due to harmful chemicals. The biosynthesis of zinc oxide nanoparticles was achieved using the hot water extract of Sargassum wightii (SW), which serves as a reducing agent. This extract is mixed with zinc precursors, initiating a bio-reduction process. UV-vis, FTIR, XRD, Raman, DLS, SEM, EDX, TEM imaging, and XPS analysis are used. The novelty of this research lies in utilizing a bio-reduction process involving hot water extract of SW to synthesize zinc oxide nanoparticles, providing a safer and eco-friendly alternative to traditional chemical methods. Here, the zinc oxide nanoparticles produced through the biosynthesis process effectively addressed oral infections (Streptococcus mutans) due to their ability to disrupt the integrity of bacterial cell membranes, interfere with cellular processes, and inhibit the growth and proliferation of bacteria responsible for oral infections. Gaussian Mixture Models (GMMs) uncover intricate patterns within medical data, enabling enhanced diagnostics, treatment personalization, and patient outcomes. This study aims to apply Gaussian Mixture Models (GMMs) to medical data for subpopulation identification and disease subtyping, contributing to personalized treatment strategies and improved patient care. With a dataset comprising 300 samples, the application of GMM showed lower BIC and AIC values (2500, 3200), a high Silhouette Score (0.65 from -1 to 1) reflecting well-defined clusters, Calinski-Harabasz (120) and Davies-Bouldin Indices (0.45). These metrics collectively underscored the model's success in revealing distinct patterns within the data. ZnO-nanocoated aligners were effective against Streptococcus mutans, with the maximum antibacterial effect observed for 2 days and lasting for 7 days.

3.
Hortic Res ; 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35043168

RESUMO

Radish (Raphanus sativus L.) belongs to the family Brassicaceae. The Yunnan red radish variety contains fairly relatively large amounts of anthocyanins, making them important raw materials for producing edible red pigment. However, the genetic mechanism underlying this pigmentation has not been fully characterized. Herein, the radish inbred line YAAS-WR1 (white root-skin and white root-flesh) was crossed with the inbred line YAAS-RR1 (red root-skin and red root-flesh) to produce F1, F2, BC1P1, and BC1P2 populations. Genetic analyses revealed that the pigmented/non-pigmented (PiN) and purple/red (PR) traits were controlled by two genetic loci. The F2 population and the specific-locus amplified fragment sequencing (SLAF-seq) technique were used to construct a high-density genetic map (1230.16 cM), which contained 4032 markers distributed in nine linkage groups, with a mean distance between markers of 0.31 cM. Additionally, two QTL (QAC1 and QAC2) considerably affecting radish pigmentation were detected. A bioinformatics analysis of the QAC1 region identified 58 predicted protein-coding genes. Of these genes, RsF3'H, which is related to anthocyanin biosynthesis, was revealed as a likely candidate gene responsible for the PR trait. The results were further verified by analyzing gene structure and expression. Regarding QAC2, RsMYB1.3 was determined to be a likely candidate gene important for the PiN trait, with a 4-bp insertion in the first exon that introduced a premature termination codon in the YAAS-WR1 sequence. Assays demonstrated that RsMYB1.3 interacted with RsTT8 and activates RsTT8 and RsUFGT expression. These findings may help clarify the complex regulatory mechanism underlying radish anthocyanin synthesis. Furthermore, this study's results may be relevant for the molecular breeding of radish to improve the anthocyanin content and appearance of the taproots.

4.
Rev Sci Instrum ; 91(12): 125006, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379999

RESUMO

A significant issue of land vehicle navigation is in-motion attitude alignment of the odometer (OD)-aided strapdown inertial navigation system (SINS). The consecutive OD outliers can occur due to sudden wheel slipping and skidding while vehicle maneuvering. They seriously reduce the robustness and precision of attitude alignment. In this paper, we investigate a robust in-motion attitude alignment method for the OD-aided SINS. The method consists of in-motion coarse alignment and in-motion fine alignment. In the in-motion coarse alignment process, we developed Huber's M-estimation and integral formula based robust Kalman filter (HRKF/IF-CA), which can restrain the interference of consecutive OD outliers on reconstructed observation vectors. Thus, HRKF/IF-CA can contribute to better coarse attitude results. The next process is in-motion fine alignment. Under the popular repeated backtracking scheme, we investigate HRKF based fine alignment (HRKF-FA) with the SINS/OD summed measurement model. HRKF-FA can refine attitude alignment and restrain the interference of consecutive OD outliers simultaneously. Finally, the proposed method is evaluated by simulation and vehicle test. The attitude alignment results show that this method can achieve reasonable attitude results, and the interference of consecutive OD outliers caused by sudden wheel slipping and skidding can be greatly restrained.

5.
Plant Cell Rep ; 34(8): 1295-306, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25861729

RESUMO

KEY MESSAGE: AtWRKY53 is an early factor in drought response and activated expression of AtWRKY53 regulates stomatal movement via reduction of H 2 O 2 content and promotion of starch metabolism in guard cells. Drought is one of the most serious environmental factors limiting the productivity of agricultural crops worldwide. However, the mechanisms underlying drought tolerance in plants remain unclear. AtWRKY53 belongs to the group III of WRKY transcription factors. In this study, we observed both the mRNA and protein products of this gene are rapidly induced under drought conditions. Phenotypic analysis showed AtWRKY53 overexpression lines were hypersensitive to drought stress compared with Col-0 plants. The results of stomatal movement assays and abscisic acid (ABA) content detection indicated that the impaired stomatal closure of 53OV lines was independent of ABA. Further analysis found that WRKY53 regulated stomatal movement via reducing the H2O2 content and promoting the starch metabolism in guard cells. The results of quantitative real-time reverse transcriptase PCR showed that the expression levels of CAT2, CAT3 and QQS were up-regulated in 53OV lines. Chromatin immunoprecipitation assays demonstrated that AtWRKY53 can directly bind to the QQS promoter sequences, thus led to increased starch metabolism. In summary, our results indicated that the activated expression of AtWRKY53 inhibited stomatal closure by reducing H2O2 content and facilitated stomatal opening by promoting starch degradation.


Assuntos
Proteínas de Arabidopsis/fisiologia , Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Estômatos de Plantas/fisiologia , Ácido Abscísico/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Desidratação/genética , Desidratação/fisiopatologia , Peróxido de Hidrogênio/metabolismo , Fenótipo , Transpiração Vegetal/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Amido/metabolismo
6.
Nanoscale Res Lett ; 10: 17, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25852315

RESUMO

We study the optical properties of the nanosphere-in-a-nanoegg structure (NSNE) by the three-dimensional finite difference time domain method. We demonstrate the suppression of the high-order plasmon modes in NSNE, which is induced by the plasmon interaction between the inner nanosphere and the outer nanoegg shell. A two-layer plasmon hybridization model is presented to explain this mechanism. The results we showed for plasmon mode suppression would be important to the design of the metal plasmonic devices. In addition, due to high tunable plasmon resonances in the near-infrared region (700 to 1,300 nm) with sub-100-nm size, NSNE can serve as a good substitute for the Au-silica-Au multilayer nanoshells in biological applications. Furthermore, compared with the Au-silica-Au nanoshells, NSNE has the advantage that the strong field enhancement can be achieved at the outer surface of the Au shell.

7.
Zhongguo Yi Liao Qi Xie Za Zhi ; 38(3): 219-21, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25241522

RESUMO

This paper introduces several test methods of characteristics of alarm indicator lights which can be used in the medical alarm system to verify the compliance of YY 0709-2009. These methods include the direct measurement of the pulse current supply of the alarm signals, image analysing of a video and reception by photoelectric sensor. After the comparation of the advantages and disadvantages among these methods, this paper proposes a new method of signal reception. This method which used a silicon photocell as the sensor with light filter in its front, and amplified circuit in the output end then used an oscillograph as the reviewer, has resolved the testing difficulties of the flashing signal simulating by LCD, and can be applied to test the alarm indicator lights in any medical electrical equipment.


Assuntos
Alarmes Clínicos , Processamento de Sinais Assistido por Computador , Desenho de Equipamento
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