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Dynamic mesh atomizers have been widely used in various fields because of their compact structure, low energy consumption, and low production costs. The finite element method is an important technique to analyze the factors affecting the atomization performance of dynamic mesh atomizers. However, at present, there is a lack of decisive solutions to the basic problems of boundary setting in terms of the simulation and vibration displacement characteristics of atomizers under different vibration modes. In this paper, two errors were found in the Vibration Analysis of a Piezoelectric Ultrasonic Atomizer to Control Atomization Rate paper written by Esteban Guerra-Bravo et al. in 2021. First, in the finite element analysis, the boundary condition of the atomizing sheet was set to be fixed, which is inconsistent with the actual support situation and seriously affects the vibration of the atomizing sheet. Second, in the simulation result, from the first mode to the third mode, the growth rate of the maximum displacement at the center of the atomizing sheet was as high as 77.12%, even up to 221.05%, which is inconsistent with the existing vibration theory. In view of these errors, in this paper, the working principle of dynamic mesh atomizers is analyzed and the vibration equation of the atomizing sheet under peripheral simple support is derived. Through comparison with the literature, it was proven that the boundary setting and vibration displacement of the atomizing sheet in the original paper are unreasonable. By measuring the atomizing rate of the atomizing sheet under different boundary conditions, it was proven that the peripheral freedom of the atomizing sheet should be greater than or equal to 1, namely, peripheral freedom or peripheral simply supported. The vibration displacement theory was used for the simulation, and the relationship between the vibration displacement and resonant frequency of the atomizing sheet under peripheral simple support was measured. It was found that with the increase in the resonance frequency, the maximum displacement of vibration modes with only nodal circles was larger than that of the other vibration modes, and the maximum displacement increased slightly with the increase in the number of nodal circles by about 0.98%.

Aims: Carbapenem-resistant K. pneumoniae (CRKP) is the most common carbapenem-resistant Enterobacteriaceae with high mortality. Ceftazidime-avibactam (CAZ-AVI) has exhibited excellent in vitro activity in vivo against CRKP. However, the efficacy of CAZ-AVI in KPC-producing CRKP-infected patients with different kidney statuses varies, such as renal insufficiency, normal renal function, and augmented renal clearance (ARC). We explored the use of therapeutic drug monitoring (TDM) to evaluate the concentration and efficacy of CAZ-AVI in CRKP-infected patients with different kidney statuses.Methods: Serum concentrations for CAZ and AVI were determined by the high-performance liquid chromatography method. Bacterial identification, routine susceptibility testing, renal function index, and others were performed in standard protocols in the hospital’s clinical laboratories.Results: In the two patients with ARC, in case 1, CAZ-AVI 2.5g q6h was used with good efficacy, and the concentrations were up to the pharmacokinetics/pharmacodynamics targets. In Case 2, 2.5 g q8h was used with invalid effectiveness, and AVI Cmin was only 0.797 mg/l, which is lower than the PK/PD target. Case 3 was renal insufficiency using CAZ-AVI 1.25 q8h, and case 4 was normal renal function using 2.5 g q8h. Their concentrations were both up to the PK/PD targets.Conclusion: TDM results demonstrated that CAZ-AVI steady-state plasma concentration varies among patients with different kidney statuses, providing evidence for the utility of TDM of CAZ-AVI in individualized drug dose adjustment. ARC patients may need more CAZ-AVI daily doses than the standard dose.

Deoxyribonucleic acid (DNA) methylation is an important epigenetic mark involved in diverse biological processes. Here, we report the critical function of tomato (Solanum lycopersicum) Domains Rearranged Methyltransferase7 (SlDRM7) in plant growth and development, especially in leaf interveinal chlorosis and senescence. Using a hairpin RNA-mediated RNA interference (RNAi), we generated SlDRM7-RNAi lines and observed pleiotropic developmental defects including small and interveinal chlorosis leaves. Combined analyses of whole genome bisulfite sequence (WGBS) and RNA-seq revealed that silencing of SlDRM7 caused alterations in both methylation levels and transcript levels of 289 genes, which are involved in chlorophyll synthesis, photosynthesis, and starch degradation. Furthermore, the photosynthetic capacity decreased in SlDRM7-RNAi lines, consistent with the reduced chlorophyll content and repression of genes involved in chlorophyll biosynthesis, photosystem, and photosynthesis. In contrast, starch granules were highly accumulated in chloroplasts of SlDRM7-RNAi lines and associated with lowered expression of genes in the starch degradation pathway. In addition, SlDRM7 was activated by aging- and dark-induced senescence. Collectively, these results demonstrate that SlDRM7 acts as an epi-regulator to modulate the expression of genes related to starch and chlorophyll metabolism, thereby affecting leaf chlorosis and senescence in tomatoes.

Piezoelectric atomization, which breaks liquid into tiny droplets, is widely used in aerospace, medicine, and health. Most research in piezoelectric atomizers has increased the atomization amount by improving mechanical structure and optimizing the vibration characteristics. However, as the core component of the atomizer is to realize atomization using the dynamic conical angle effect, the micro-tapered hole on the atomizing sheet has not been deeply studied. To eliminate the negative influence of the uneven burr caused by the hole machining process on the atomizing sheet, electrolytic polishing processing is proposed in this study to improve the quality of the micro-tapered holes. First, a theoretical model of the atomization amount and the conical angle is established. Second, the hole diameter and burr height are measured using a microscope, and the effectiveness of polishing on the burr removal of holes is verified. Lastly, the relationship between the conical angle and atomization amount is determined through an atomization amount experiment, which guides the revision of the theoretical model. The experimental results show that when the conical angle is 48,267° (the polishing time is 5 min), the atomization amount reaches a maximum of 5.202 mL/min, which is 3.93 times larger than that of the untreated one. This study demonstrates that polishing can effectively remove burr in the process of hole machining, which provides theoretical guidance for improving the quality of atomization sheets, and will further improve the atomization number of atomizers.

In this paper, a dye modified titanium dioxide/graphene composite (DTG20) was prepared using direct grey D, a dye with good water solubility, as a modifier. Then the DTG20 and its intermediates, including TiO2 and titanium dioxide/graphene (TG), were finished on cotton fabric through the padding, coating and compounding methods, respectively. Photocatalytic properties of the treated fabrics were investigated using the MB simulated pollutant. It was found that the photodegradation efficiency of MB shown by DTG20 finished fabric treated with the compounding method can reach 90.55 %, and after four recycling experiments, the removal rate of MB can still reach 77.07 %. After being exposed to sunlight for 6 hours, the photodegradation efficiency of MB stained on the surface of DTG20 treated fabric can achieve 91.44 %; therefore, it also exhibited an excellent self-cleaning effect. [ABSTRACT FROM AUTHOR]