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Objective To investigate the antibacterial effect and its preliminary mechanism of lavender essential oil on multi-drug resistant Acinetobacter baumannii. Methods Micro-dilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of lavender essential oil against multi-drug resistant Acinetobacter baumannii, and bactericidal kinetic study was employed to determine the onset and maintenance time of lavender essential oil. Meanwhile, the promoting and therapeutic effects of lavender essential oil on wound healing were observed in a mouse model of infection. Subsequently, crystal violet staining was used to determine the inhibition and clearance of multi-drug resistant Acinetobacter baumannii biofilm by lavender essential oil, and laser confocal microscopy was utilized to observe the survival of bacteria in biofilms. NanoDrop instrument was utilized to quantify the leakage of bacterial DNA nucleic acid and protein after intervention with 3 and 6 mg/mL lavender essential oil, and the leakage of bacterial potassium ion was measured by potassium ion test kit. Proteomics technology combined with bio-informatics were applied to explore the action mechanism of lavender essential oil against multi-drug resistant Acinetobacter baumannii. Results The MIC and MBC of lavender essential oil were both 6 mg/mL, which could kill almost all multi-drug resistant Acinetobacter baumannii at the time point of 120 min, and showed an obvious dose- and time-dependent manner. The overall animal model evaluation showed that both 3 and 6 mg/mL lavender essential oil could promote wound healing, and the curative effect was obvious. Further studies confirmed that 3 mg/mL lavender essential oil had a certain biofilm inhibitory effect on multi-drug resistant Acinetobacter baumannii, and 6 mg/mL also had a certain biofilm clearance effect under the same conditions. Meanwhile, when incubated at 37 ℃ for 1 h, the dose of 3 mg/mL could increase the leakage of DNA nucleic acid and protein, and significantly promote the efflux of potassium ions. Proteomic analysis suggested that the antibacterial effect of lavender essential oil may be related to affecting the oxidorereductase activity and cell metabolic process of multi-drug resistant Acinetobacter baumannii, and interfering with the biosynthesis of cell wall/membrane/envelope and other structures. Conclusion Lavender essential oil at 3 mg/mL can play an antibacterial effect against multi-drug resistant Acinetobacter baumannii, and its mechanism may be related to the destruction of bacterial biofilm and interference with bacterial metabolism.

Although K0.5Na0.5NbO3 (KNN) possesses large maximum polarization and relatively high breakdown strength, the large remnant polarization constrains their practical applications as energy storage materials. In this work, through multi-element doping, (K0.5−0.5xNa0.5−0.5xBix)(Nb1−xSn0.2xZn0.6xTa0.2x)O3 relaxor ferroelectrics were prepared. As the superparaelectric states (SPE) were adjusted to room temperature, orthorhombic, tetragonal, and cubic phases coexisted, accompanied by the highly dynamic polar nanoregions (PNRs). In particular, a high recoverable energy storage density of 4.5 J/cm3 and an energy storage efficiency of 83% were achieved for the x = 0.125 ceramic, with the variations less than 11% and 4%, respectively, in the wide temperature range of 20–180 °C. These results demonstrate that the multiphase PNRs in the SPE state is an effective strategy for improving the energy storage performance of KNN-based ceramics. [ABSTRACT FROM AUTHOR]

In this study, a magnetic relaxation immunosensor based on gold core@platinum shell (Au@Pt) nanozyme-mediated paramagnetic ion valence transition was constructed and used for the rapid detection of Salmonella in foods. Pt@Au nanozyme with high stability and good catalytic performance was synthesized by a microwave-assisted hydrothermal (MAH) method, and its catalase-like activity was used to catalyze hydrogen peroxide (H2O2). The remaining H2O2 could convert MnO4- into Mn2+ through a redox reaction. The significant difference in magnetic signals between MnO4? and Mn2+ allowed the quantitative analysis of hydrogen peroxide. In the immunoreaction, the concentration of Salmonella was directly proportional to the content of “detection antibody-Pt@Au”. Au@Pt could regulate the H2O2-mediated MnO4?/Mn2+ conversion system and consequently control the change of magnetic signal, ultimately allowing the quantitative analysis of Salmonella. The detection limit of this method for Salmonella was 50 CFU/mL, and the linear range was 1 × 102–5 × 107 CFU/mL. The results of this method for Salmonella in eggs were in good agreement with those of fluorescence quantitative polymerase chain reaction (PCR). This method has the advantages of high sensitivity, good stability, simple operation and low cost, thus having a good application prospect in the rapid detection of foodborne pathogens.

【Objective】 A porous filter is often used in micro-irrigation systems to filter debris and sand particles. Its performance depends on many factors. The purpose of this paper is to present a method to optimize its operating conditions. 【Method】 The studies were based on a micro-pressure filter. We took water pressure loss, sand interception rate and filtration efficiency as assessment criteria. In the experiments we measured and calculated the combined impact of inlet flow, sediment content, water-separator type, and filter area on operation of the filter. The results were processed using the analysis of range and variance. 【Result】 The factors that affected the head loss of muddy water across the filter were ranked in the descending order of inlet flow > sediment content > filter area > water separator type. The factors that impacted the mass of sand trapped by the filter were ranked in the descending order of sediment content > filter area > water separator type > inlet flow rate. The factors that affected the total filtration efficiency were ranked in the descending order of filter area > sediment content > water separator type>inlet flow rate. 【Conclusion】 The two factors that affected water head loss across the filter, sediment filtration and total filtration efficiency most are sediment content and filter area. Comprehensive analysis shows that the optimal operating conditions for the filter are sediment concentration 0.36 kg/m3, inflow rate 4 m3/h, water separator type Type 3, filter area 2 060 cm2.

This study aims to integrate a convolutional neural network (CNN) and the Random Forest Model into a rehabilitation assessment device to provide a comprehensive gait analysis in the evaluation of movement disorders to help physicians evaluate rehabilitation progress by distinguishing gait characteristics under different walking modes. Equipped with accelerometers and six-axis force sensors, the device monitors body symmetry and upper limb strength during rehabilitation. Data were collected from normal and abnormal walking groups. A knee joint limiter was applied to subjects to simulate different levels of movement disorders. Features were extracted from the collected data and analyzed using a CNN. The overall performance was scored with Random Forest Model weights. Significant differences in average acceleration values between the moderately abnormal (MA) and severely abnormal (SA) groups (without vehicle assistance) were observed (p < 0.05), whereas no significant differences were found between the MA with vehicle assistance (MA-V) and SA with vehicle assistance (SA-V) groups (p > 0.05). Force sensor data showed good concentration in the normal walking group and more scatter in the SA-V group. The CNN and Random Forest Model accurately recognized gait conditions, achieving average accuracies of 88.4% and 92.3%, respectively, proving that the method mentioned above provides more accurate gait evaluations for patients with movement disorders. [ABSTRACT FROM AUTHOR]