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Green chemistry has been a rising topic in environmental sustainability, with a focus on the waste and consumption reduction of chemical and biomedical industries. Traditional chemical handling processes require tools that contact chemical reagents to produce vast amounts of residues and disposals. This study presents a contactless chemical mixing system that integrates acoustic droplet ejection and levitation techniques. First, the acoustic droplet ejection system creates a droplet in mid-air from a designated liquid reservoir by focusing acoustic energy at the liquid-air junction. The droplet levitation system captures and transports the droplet along a predetermined path by shifting the focal points of the acoustic standing waves. This facilitates contactless mixing of chemicals in a defined ratio. Notably, this study employs piezoelectric discs in an acoustic droplet ejection system to eject droplets from liquids. The relationship between the duration of the driving bursts and height and size of ejected droplets was also investigated. The proposed acoustic standing wave levitation system captures droplets with weights between 2.8 and 5.2 mg. To assess the reliability of the proposed system, 25 droplets were sequentially generated and transported to the mixing well without failure. The root mean square error between the collected and expected liquid weights was only 0.098 mg. The proposed system offers a promising solution for reducing waste and promoting environmentally friendly practices in chemical and biomedical laboratories., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [Chih-Hsien Huang reports financial support was provided by National Science and Technology Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper]., (Copyright © 2024 Elsevier B.V. All rights reserved.)

With continuous development of pesticide dosage forms, emulsifiable concentrates using large amounts of organic solvents are gradually obsoleted. Nanoemulsions with high water content have been developed and the preparation processes also evolved, but these processes still exist some problems, such as poor controllability and high energy consumption. Microfluidic is a controllable nanoemulsion preparation system which mainly applied to pharmaceutical synthesis. In this study, the pesticide phoxim nanoemulsion was prepared by microfluidic technology. The optimized formulation of phoxim nanoemulsion was composed of Tween 80 and pesticide emulsifier 500 as surfactant, hexyl acetate as oil, and n-propanol as co-surfactant. Moreover, when the flow rates of water and oil in the microfluidic system were adjusted to 5 μL/min and 20 μL/min, phoxim nanoemulsion was obtained with a cloud point/boiling point of 109 °C, a particle size of 21.5 ± 0.8 nm and a potential value of - 18.7 ± 0.6 mV. Furthermore, the nanoemulsion had a rapid release effect in vitro which could be fitted by the Ritger-Peppas model. The feeding toxicity of the phoxim nanoemulsion was higher than that of commercial formulation while the contact killing effect was higher than that of the active ingredient. Therefore, pesticide dosage was reduced and the insecticidal effect was enhanced by using phoxim nanoemulsions. These results also confirm the potential of microfluidics as a green process to produce pesticide nanoemulsions., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To increase the reuse of food residues, multifrequency countercurrent ultrasonic treatment was used to enhance the extraction yield of defatted mulberry seed protein (DMSP), and sweet-flavored peptides from DMSP hydrolysates (DMSPHs) were obtained for the first time. Here, the DMSP yield was increased by 16.2% (p < 0.05) while the power density was halved compared with single-frequency ultrasonic treatment. According to Fick's second law, a molecular diffusion dynamics model was developed to be suitable for predicting the pretreatment conditions (R 2  = 0.9785). After that, the sweet-flavored peptides were purified and the main amino acid sequences were identified, i.e., FEGGSIE, KDFPEAHSQAT, and GSQPAEGAK. Moreover, the antioxidant activities of DMSPHs prepared with tri-frequency treatment was higher than 60%. The DMSPHs retarded the growth of HepG2 cells in vitro, increased the necrotic quadrant (Q1-UL), and extended the S phase. Therefore, the sweet-flavored peptides prepared from DMSPHs using the multifrequency-ultrasonic treatment have significant biological activities., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Parkinson's disease (PD) is a common neurodegenerative movement disorder, but the pathogenesis is still unclear. Long non-coding RNAs (lncRNAs) have been reported to play a prominent role in PD., Objective: This study is designed to explore the role and mechanism of long intergenic non-coding RNA 00943 (LINC00943) in the N-methyl-4-phenylpyridine (MPP + )-inducted PD model., Methods: LINC00943, microRNA-7-5p (miR-7-5p), and the chemokine (C-X-C motif) ligand 12 (CXCL12, also referred to as SDF-1) level were examined by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability and apoptosis were analyzed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), and flow cytometry assays, severally. Protein levels of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and CXCL12 were assessed by western blot assay. The ROS generation and SOD activity were detected by the corresponding kits. The binding relationship between miR-7-5p and LINC00943 or CXCL12 was predicted by Starbase and then verified by a dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays., Results: LINC00943 and CXCL12 were increased, and miR-7-5p was decreased in MPP + -inducted SK-N-SH cells. LINC00943 silencing promoted cell viability, and repressed apoptosis and the inflammatory response in MPP + -treated SK-N-SH cells. The mechanical analysis discovered that LINC00943 acted as a sponge of miR-7-5p to regulate CXCL12 expression., Conclusions: LINC00943 knockdown could attenuate MPP + -triggered neuron injury by regulating the miR-7-5p/CXCL12 axis, hinting at a promising therapeutic target for PD treatment.

In order to study the pollution characteristics and causes of winter haze pollution in Beijing, a typical PM 2.5 pollution process in Beijing in December 2019 was used as the analysis object using aerosol vertical detection data, boundary layer meteorological field and near-ground turbulence data, and the difference in haze. The characteristics of the pollution stage and the evolution of the physical and chemical characteristics of the boundary layer were comprehensively analyzed. The results showed that ① the pollution process in Beijing during the observation period lasted 5 d and experienced two generations and eliminations. The maximum hourly PM 2.5 concentration was 220 μg·m -3 and the time exceeding the severe pollution standard was 64 h, thereby accounting for 53% of the total time. ② The aerosol optical properties and meteorological field observation data showed that the pollution originated from the regional transmission of aerosols and water vapor on the surface of the southwest urban agglomeration in Beijing, which accounted for 48% of the total pollution transmission, followed by a stable high-altitude situation and ground pressure field configuration. The near-surface layer maintained weak southerly winds (wind speed: 1-2 m·s -1 ), a strong inversion temperature close to the ground ［0.8 K·(100 m) -1 ］, high humidity (relative humidity above 80%), and other unfavorable diffusion weather conditions, thereby promoting the accumulation of pollutants and the conversion of moisture absorption. Superimposing local pollution emissions were the main reasons for the maintenance of haze days. In addition, the near-ground extinction coefficient increased from 0.070 km -1 to 5.954 km -1 , and the depolarization ratio decreased from 0.05 to 0.02 during the two pollution generation and disappearance processes, thereby indicating that the spherical characteristics of aerosols gradually became significant as the pollution increased. ③ The analysis of the turbulence observation data showed that the characteristic quantities of different pollution stages were significantly different and negatively correlated with the pollutant concentration. Before the occurrence of heavy pollution, the turbulence statistics (turbulence intensity, friction velocity, and turbulent kinetic energy) suddenly decreased from high values (the hourly variation rate was 77%, thereby far exceeding the daily fluctuation of 33%), and the turbulence intensity responded first. During the pollution accumulation stage, the friction velocity (0.04-0.21 m·s -1 ), turbulence intensity (average: 0.678 m 2 ·s -2 ), and turbulence energy (average: 0.643 m 2 ·s -2 ) were maintained at a low level, and the bottom atmosphere had a poor mixing and diffusion ability, which is important for continuous pollution accumulation. Four hours before the end of the pollution event, the turbulence intensity again showed a sharp increase (increment of more than one order of magnitude); thus, the turbulence intensity can be used as a predictive indicator of the occurrence and end of a heavy pollution event, and the response time is the same as the continuous turbulence intensity after the turbulence peak. In addition, the sensible heat fluxes on sunny days and haze days were both transported from the ground to the atmosphere, and showed clear daily single-peak changes. The sensible heat flux on haze days (20 W·m -2 ) was smaller than that on sunny days (60 W·m -2 ). The latent heat flux was approximately 0 W·m -2 in the whole process. ④ There was a feedback effect between the meteorological conditions of the pollution layer and the boundary layer. On the one hand, unfavorable diffusion of the meteorological conditions was conducive to the accumulation of pollution. On the other hand, the aerosol layer and water vapor cooling effect that accumulated near the ground were worse than the night cooling radiation on the inversion layer The contribution was greater, thereby further inhibiting the development of turbulent motion and ultimately resulting in increased pollution.

Objectives: We examined whether or not changing work stressors and coping resources affect the risk of psychological distress., Method: A baseline evaluation of work stressors and coping resources and mental health was assessed for 4362 petroleum industry workers after 12 years., Results: Increased task and organizational stressors were associated with an elevated risk of psychological distress. Decreased task stressors, increased job control, and increased coping resources were associated with a reduced risk of psychological distress. Increased coping also had a buffering effect on increased work stressors and psychological distress. Gender-specific differences were observed in the factors influencing mental health., Conclusions: The findings indicated that reducing gender-specific task and organizational stressors, and promoting coping resources at work may help prevent the onset of psychological distress.

Aims: Increasing age is a significant risk factor for developing atrial fibrillation (AF). Pulmonary vein (PV) triggers are critical in the mechanism of AF, but little is known of the substrate changes that occur within the PVs with ageing. Therefore, we sought to identify whether ageing is associated with electroanatomic changes within the pulmonary veins., Methods and Results: Twenty-five patients undergoing ablation for left-sided supraventricular tachycardia had high-density 3D electroanatomic maps of all four PVs created. Patients were divided into two groups: group 1 aged <50 years and group 2 aged >50 years. Mean-voltage (MV), % low-voltage (LV < 0.5 mV), conduction, signal complexity, and PV muscle sleeve length and diameter were assessed. Age was 33 ± 8 vs. 66 ± 8 years for groups 1 and 2, respectively (P < 0.001). Group 2 demonstrated: (i) lower MV within the PVs (1.66 ± 1.1 vs. 1.88 ± 1.1 mV, P < 0.001); (ii) increased % LV (5.0 vs. 1.1%, P < 0.001), and increased voltage heterogeneity within the PVs (65 ± 14 vs. 55 ± 8%, P < 0.05); (iii) regional and global conduction slowing in the PVs; and (iv) increased % complex signals within the PVs (1.4 vs. 0.4%, P = 0.009). There was no difference in PV sleeve length or diameter., Conclusion: Increasing age is associated with PV electroanatomic changes characterized by a significant reduction in PV voltage, conduction slowing, and increasing signal complexity. These observations provide new insights into the potential mechanisms behind the increased prevalence of AF with advancing age.

A highly doped Er3+: LiNbO3 (concentration 6 mol%) crystal was grown successfully by Czochralski method. The crystal is higher than that of the lowly doped Er3+ in LiNbO3 crystal, which is helpful to improve absorption coefficient of the grown the pumping efficiency. The absorption spectra at two unpolarized directions (X and Z) and two polarized directions (E parallel Z, E perpendicular Z) were measured. Using the Judd-Ofelt theory, and according to the measured absorption spectra, the intensity parameters omegalambda of Er3+ were fitted. The results of root-mean square (r. m. s) deviation show that the error of polarized fitting is less than that of unpolarized one. Thus fluorescence transition probabilities (Ajj), radioactive lifetime (tau), fluorescence branching ratio (beta), and integrated emission cross section (sigmap) were calculated and accepted according to the polarized results, and were also discussed and compared with the ones reported in the literature.

We have demonstrated a passively mode-locked diode end-pumped all-solid-state laser, which is composed of a Nd:Gd0.5Y0.5VO4 crystal and a folded cavity with a semiconductor saturable-absorber mirror grown by metal-organic chemical-vapor deposition. Stable cw mode locking with a 3.8-ps pulse duration at a repetition rate of 112 MHz was obtained. At 13.6 W of the incident pump power, a clean mode-locked fundamental-mode average output power of 3.9 W was achieved with an overall optical-to-optical efficiency of 29.0%, and the slope efficiency was 38.1%.