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Cysteine (Cys), as one of the biological thiols, is related to many physiological and pathological processes in humans and plants. Therefore, it is necessary to develop a sensitive and selective method for the detection and imaging of Cys in biological organisms. In this work, a novel near-infrared (NIR) fluorescent probe, Probe-Cys, was designed by connecting furancarbonyl, as a new recognition moiety, with Fluorophore-OH via the decomposition of IR-806. The use of the furan moiety is anticipated to produce more effective fluorescence quenching because of the electron-donating ability of the O atom. Probe-Cys has outstanding properties, such as a new recognition group, an emission wavelength in the infrared region at 710 nm, a linear range (0-100 µM), a low detection limit of 0.035 µM, good water solubility, excellent sensitivity, and selectivity without the interference of Hcy, GSH, and HS-. More importantly, Probe-Cys could achieve the detection of endogenous Cys by reacting with the stimulant 1,4-dimercaptothreitol (DTT) and the inhibitor N-ethylmaleimide (NEM) in HepG2 cells and zebrafish. Ultimately, it was successfully applied to obtain images of Arabidopsis thaliana, revealing that the content of Cys in the meristematic zone was higher than that in the elongation zone, which was the first time that the NIR fluorescence probe was used to obtain images of Cys in A. thaliana. The superior properties of the probe exhibit its great potential for use in biosystems to explore the physiological and pathological processes associated with Cys.
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Arabidopsis , Perciformes , Humanos , Animais , Fluorescência , Peixe-Zebra , Cisteína , Células HeLa , Corantes Fluorescentes , GlutationaRESUMO
Transparent conductive thin films (TCO) are widely used for their excellent photoelectric properties. To prepare high-quality ZnO targets, starting with the original ZnO powder is necessary. This paper aims to explore the basic technology and method of ultrasonic-assisted direct precipitation for mass production of ZnO powder and to analyze the effects of factors such as precipitating agent, surfactant, calcination temperature, and solvent on the powder's morphology, particle size, and crystallinity. The study found that the type and amount of precipitants and surfactants affect the powder's morphology and dispersibility, while calcination temperature mainly affects the powder's morphology and crystallinity. The ethanol content in the solvent mainly affects the grain size. After testing different variables, the optimal conditions for preparing spherical ZnO powder were found to be using (NH4)2·CO3 as the precipitant, adding 3% wt of PEG-400 and 3% wt of TEA at a calcination temperature of 320°C and a 60% ethanol solvent. This resulted in a smooth surface, uniform particle size distribution, good dispersibility, high crystallinity, and particle sizes between 26-32nm.
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Ultrassom , Óxido de Zinco , Pós , Tensoativos , Etanol , SolventesRESUMO
Objective: This study aimed to perform a systematic review and meta-analysis to identify the efficacy of acupuncture therapy (including manual acupuncture and electroacupuncture) performed before or during gastrointestinal endoscopy with propofol as the main sedative, compared with placebo, sham acupuncture, or no additional treatment other than the same sedation. Methods: A systematic search was performed through PubMed, Embase, Web of Science, Cochrane Library, Chinese Biomedical Databases (CBM), Wanfang database, China National Knowledge Infrastructure (CNKI), SinoMed, and Chinese Scientific Journal Database (VIP) to collect randomized controlled trials published before 5 November 2022. Bias assessment of the included RCTs was performed according to Version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2). Stata16.0 software was used to perform statistical analysis, sensitivity analysis, and publication bias analysis. The primary outcome was sedative consumption, and the secondary outcomes included the incidence of adverse events and wake-up time. Results: A total of 10 studies with 1331 participants were included. The results showed that sedative consumption [mean difference (MD) = -29.32, 95% CI (-36.13, -22.50), P < 0.001], wake-up time [MD = -3.87, 95% CI (-5.43, -2.31), P < 0.001] and the incidence of adverse events including hypotension, nausea and vomiting, and coughing (P < 0.05) were significantly lower in the intervention group than in the control group. Conclusion: Acupuncture combined with sedation reduces sedative consumption and wake-up time compared with sedation alone in gastrointestinal endoscopy; this combined approach allows patients to regain consciousness more quickly after examination and lower the risk of adverse effects. However, with the limited quantity and quality of relevant clinical studies, caution must be applied until more high-quality clinical studies verify and refine the conclusions. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?, identifier: CRD42022370422.
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TiAlN-coated carbide tools have been used to machine Ti-6Al-4V alloys in aviation workshops. However, the effect of TiAlN coating on surface morphology and tool wear in the processing of Ti-6Al-4V alloys under various cooling conditions has not been reported in the public published literature. In our current research, turning experiments of Ti-6Al-4V with uncoated and TiAlN tools under dry, MQL, flood cooling, and cryogenic spray jet cooling conditions were carried out. The machined surface roughness and tool life were selected as the two main quantitative indexes for estimating the effects of TiAlN coating on the cutting performance of Ti-6Al-4V under various cooling conditions. The results showed that TiAlN coating makes it hard to improve the machined surface roughness and tool wear of a cutting titanium alloy at a low speed of 75 m/min compared to that achieved by uncoated tools. The TiAlN tools presented excellent tool life in turning Ti-6Al-4V at a high speed of 150 m/min compared to that achieved by uncoated tools. From the perspective of obtaining finished surface roughness and superior tool life in high-speed turning Ti-6Al-4V, the selection of TiAlN tools is feasible and reasonable under the cryogenic spray jet cooling condition. The dedicative results and conclusions of this research could guide the optimized selection of cutting tools in machining Ti-6Al-4V for the aviation industry.
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OBJECTIVE: During the COVID-19 pandemic, many people devoted longer time to screen viewing due to the need for study, work, and online social activities, instead of outdoor activities, which may have led to an increase in dry eye symptoms. This study aimed to evaluate the prevalence of dry eye during the COVID-19 pandemic. METHODS: PubMed, Cochrane Library, Embase, and Web of Science were searched from January 1, 2020 to October 20, 2022. Cross-sectional surveys on dry eye prevalence conducted after January 1, 2020 were included. Two review authors independently performed data extraction and assessed study quality. The random-effects model was used to analyze the prevalence of dry eye, and the odds ratio was used to assess the strength of the association between variables. Subgroup analysis was performed to detect heterogeneity, the leave-one-out method for sensitivity analysis, and the Egger test for publication bias. RESULTS: A total of eleven studies with 15692 individuals met the eligibility criteria. The prevalence of dry eye during the COVID-19 pandemic was 61.0% (95%CI: 51.8%-70.2%) globally and 56.7% (95%CI: 45.3%-68.1%) in Asia. The prevalence of dry eye had significant differences in sex and visual display time, with higher prevalence among females and visual display time of more than 4 hours per day. Subgroup analysis was performed based on diagnostic tools, study population, and average age. A significant difference was found in diagnostic tools, but no significant change in heterogeneity (P<0.05). The leave-one-out method showed stable results, and the Egger test identified no significant publication bias. CONCLUSION: The prevalence of dry eye during the COVID-19 pandemic is significantly higher than before, and a higher prevalence is found among females and those having a visual display time of more than 4 hours per day.
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COVID-19 , Síndromes do Olho Seco , Feminino , Humanos , COVID-19/epidemiologia , Prevalência , Pandemias , Estudos Transversais , Síndromes do Olho Seco/epidemiologiaRESUMO
BACKGROUND: As a major public health problem, insomnia has garnered much attention. Acupuncture, with dialectical acupoint selection (DAS), has been proved to be effective for insomnia, but there is no evidence of evidence-based medicine to prove the efficacy of Lingguibafa acupoint selection (LAS) for insomnia. This study is to evaluate the clinical efficacy of acupuncture with LAS in patient with insomnia. METHODS: The PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure, Weipu Database for Chinese Technical Periodicals, Chinese Biomedical Database, and Wanfang Database were systematically searched from the inception dates to December 18, 2021. Randomized controlled trials of acupuncture with LAS versus acupuncture with DAS or acupuncture with LAS plus DAS versus acupuncture with DAS in patient with insomnia were included. Two review authors independently performed the data extraction and assessed study quality. A meta-analysis was performed using random-effects models to calculate relative risk and weighted mean difference for categorical and continuous variables, respectively. The primary efficacy outcome was improvement on Pittsburgh Sleep Quality Index (PSQI). Secondary outcomes included insomnia severity index, Epworth sleepiness scale, Hamilton anxiety scale, Hamilton Depression Scale (HAMD), and total effective rate. RESULTS: A total of 7 trials with 468 patients fulfilled the selection criteria. The pooled results indicated that acupuncture with LAS plus DAS could reduce PSQI score by 2.08 (1.60 after excluding heterogeneity) compared to acupuncture with DAS. Acupuncture with LAS plus DAS had high reliability in sleep quality, sleep latency, sleep time and daytime function, but showed no significant effect on sleep disorder and hypnotic drug. For total effective rate, acupuncture with LAS plus DAS or acupuncture with LAS was better than acupuncture with DAS, but the conclusion was less credible. CONCLUSION: Acupuncture with LAS is significantly associated with improvements in several sleep parameters, primarily evident on the PSQI score. Nevertheless, considering the poor methodological quality, trials employing appropriate randomization concealment and blinding based on a larger sample size are needed in the future.
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Terapia por Acupuntura , Distúrbios do Início e da Manutenção do Sono , Humanos , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Reprodutibilidade dos Testes , Distúrbios do Início e da Manutenção do Sono/terapiaRESUMO
In this study, a jacobsite-biochar nanocomposite (MnFe2O4-BC) was fabricated and used to simultaneously remove Sb(iii) and Cd(ii) from water via adsorption. The MnFe2O4-BC nanocomposite was prepared via a co-precipitation method and analyzed using various techniques. The results confirm the successful decoration of the biochar surface with MnFe2O4 nanoparticles. The maximum Sb(iii) removal efficiency was found to be higher from bi-solute solutions containing Cd(ii) than from single-solute systems, suggesting that the presence of Cd(ii) enhances the removal of Sb(iii). The Langmuir isotherm model describes well Sb(iii) and Cd(ii) removal via adsorption onto the MnFe2O4-BC nanocomposite. The maximum adsorption capacities are 237.53 and 181.49 mg g-1 for Sb(iii) and Cd(ii), respectively, in a bi-solute system. Thus, the prepared MnFe2O4-BC nanocomposite is demonstrated to be a potential adsorbent for simultaneously removing Sb(iii) and Cd(ii) ions from aqueous solutions.