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In this study, a pillar[5]arene was synthesized based on trimethylamine, and its antibacterial activity and mechanism against Staphylococcus aureus ATCC 6538 and Escherichia coli DH5α were investigated. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined, and the influence of the pillar[5]arene on the formation of bacterial biofilms was evaluated. Transmission electron microscopy (TEM) was used to observe the damage to the bacterial cell membrane caused by trimethylamine-based pillar[5]arene, and the cytotoxicity was determined by the?3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium?bromide (MTT) method. The results showed that the MIC and MBC were 0.125 and 1.000 mg/mL for S. aureus ATCC 6538, respectively, and 0.250 and greater than 1.000 mg/mL for E. coli DH5α, respectively. The effect of trimethylamine-based pillar[5]arene on biofilm formation was more pronounced for S. aureus ATCC 6538 than for E. coli DH5α. TEM showed that the trimethylamine-based pillar[5]arene could differently damage the cell membrane of the two strains. The MTT assay showed that the trimethylamine-based pillar[5]arene was non-toxic within the MIC range. The results of this study provide a theoretical basis for further development and utilization of the trimethylamine-based pillar[5]arene in the food field.

The wastewater system is an important part of civil aircraft. The effective sewage discharge is closely related to the ride comfort and health of passengers. Euler method is used to simulate the gas-liquid-solid three-phase flow in wastewater system,and the effect of flight height and working condition of toilet on wastewater emission is analyzed. Results show that:when only the farthest toilet works,with the increase of flight altitude,the core peak time of waste water flow is brought forward,and the time required for wastewater to be completely discharged are significantly shortened from 3.31 s to 1.87 s,and the wastewater can be quickly discharged into the wastewater tank. When the three toilets work at the same time,the negative pressure in the wastewater pipeline will be reduced,and the flow rate of different cross sections will decrease by 66.5% on average,the toilet close to the wastewater tank will reduce the discharge efficiency of the farthest toilet,resulting in the wastewater cannot be discharged quickly. When the flushing time of toilet close to wastewater tank is adjusted to 2 s,and the farthest toilet needs to be opened separately,the wastewater in the farthest toilet can be fully discharged into the wastewater tank.Key words:civil aircraft;multi-phase flow;numerical simulation;wastewater system;toilet

Based on PowerPC architecture, this paper proposes an optimization strategy of beam pointing algorithm, which is realized from the trigonometric function calculation optimization, floating point arithmetic optimization, loop nesting optimization, and PowerPC instruction optimization. Through the optimization algorithm proposed in this paper, the processing time of the algorithm is reduced to one tenth of the original. At the same time, the optimization strategy proposed in this paper also has certain guidance and reference for the algorithm development and optimization of other platforms.

The aircraft wastewater system is an important system for civil aircraft. The wastewater is transported through the pipeline under the pressure difference between the cabin and the vacuum wastewater tank, and its flow time and characteristics are crucial for the system design. In this paper, the gas–liquid–solid flow of aircraft wastewater is investigated using the Euler–Euler–Euler multiphase flow numerical simulation method. The influencing factors of wastewater flow are analyzed. Afterward, the impact of different factors on the flow time and characteristics is analyzed, such as pressure differences between the cabin and the tank, pipeline length, pipeline inner diameter, and the disturbance for a straight long pipeline. The results show that the wastewater flow time is reduced from 6.4 to 2.6 s with the increase in the pressure difference from 20 to 60 kPa and increased from 3.4 to 10.2 s with the increase in the pipeline length from 30 to 70 m. The results obtained provide a modern theoretical basis for the design of such systems of vacuum wastewater and have a wide range of applications not only in aviation but also in other modern kinds of transport (rail, shipping), contributing to reducing their negative impact on the environment. [ABSTRACT FROM AUTHOR]

In the present study, we hypothesized that novel nanocomposites of chitosan-coated cerium oxide (CS/CeO2 NCs) derived from aqueous extracts of tea polyphenols would be stabilized and reduced by using green chemistry. The UV–visible spectrum of the synthesized material revealed an SPR peak at 279 nm, and the morphological characteristics of nanoparticles (NPs) as a uniformly distributed spherical shape with a size range of 20 nm were confirmed by field emission scanning electron microscopy (FESEM). The Fourier transform infrared spectroscopy (FTIR) spectrum illustrated the amino groups of chitosan-coated with CeO2 NPs on the surface. While, the hydrodynamic size (376 nm) and surface charge (+ 25.0 mV) of particles were assessed by dynamic light scattering (DLS), and the existence of oxidation state elements Ce 3d, O 1 s, and C 1 s was identified by employing X-ray photoelectron spectroscopy (XPS). A cubic fluorite polycrystalline structure with a crystallite size of (5.24 nm) NPs was determined using an X-ray Diffractometer (XRD). The developed CS/CeO2 NCs demonstrated excellent antibacterial and antifungal efficacy against foodborne pathogens such as Escherichia coli, Staphylococcus aureus, and Botrytis cinerea with zone of inhibition of 13.5 ± 0.2 and 11.7 ± 0.2 mm, respectively. The results elucidated the potential of biosynthesized CS/CeO2 NCs could be utilized as potent antimicrobial agents in the food and agriculture industries. [ABSTRACT FROM AUTHOR]

Background and purpose: Aphasia is a common outcome of stroke affecting one-third of the post-stroke population in China. While the quality of life (QOL) may be affected, care is often inadequately guided due to lack of validated measure for Chinese population with stroke-induced aphasia. This study aimed to develop a Chinese-version of the Stroke and Aphasia Quality of Life-39 generic version (SAQOL-39g) and evaluate its feasibility, reliability, and validity in Chinese patients with stroke-induced aphasia. Methods: The process of translation and adaptation suggested by WHO was used to develop the Chinese-version of SAQOL-39. We evaluated the feasibility, reliability, and validity of the scale in 84 aphasia patients and their proxies by assessing the internal consistency of the test items, test-retest consistency, and the structural validity of data. Results: The self-report and the proxy-report form were completed within 21.4 and 13.3 min on average, respectively. Physical, communication, and psychological subdomains were extracted as three common factors. The Cronbach's alpha coefficients of overall domain and subdomains for both forms ranged from 0.879 to 0.950, indicating high internal consistency. The intraclass correlation coefficients ranged from 0.804 to 0.987 for overall domain and subdomains of the forms. No significant difference was found between two forms. Conclusions: The Chinese-version SAQOL-39g has excellent reliability, validity, and feasibility for measuring the QOL of Chinese post-stroke aphasia patients. The consistency between self-report and proxy-report forms was good, implying that the proxy-report form can be used to assess the QOL of post-stroke aphasia patients. [ABSTRACT FROM AUTHOR]