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The in situ and straightforward fabrication of an Fe3O4-decorated 3D macroporous graphene nanozyme is developed via a facile and scalable direct-laser-writing method for catalytic–photothermal synergetic bactericidal applications.

The high strength and high hard metal materials such as nickel-based superalloy have been widely used because of their excellent properties. If the gradient nanostructures are prepared on their surfaces, their properties will be further improved and their application will be expanded. In this paper, a coupled mechanical ultrasonic-electric pulse (CMUEP) treatment method is presented and its special pulse power source with high instantaneous energy density is developed. The power supply includes main circuit, gate turn-off thyristor (GTO) control circuit, switch control circuit, display circuit, etc. The CMUEP treatment of nickel-based superalloy is carried out by using this power source. The results show that grains with the average diameter of 25.8nm are prepared on Inconel 718 surface, which can further improve the properties of the high strength and high hard metal materials and broaden their application.

Gastrodia elata Blume (G. elata), a traditional Chinese herb, known as "Tian Ma", is widely used as a common medicine and diet ingredient for treating or preventing neurological disorders for thousands of years in China. However, the anti-depressant effect of G. elata and the underlying mechanism have not been fully evaluated.The study is aimed to investigate the anti-depressant effect and the molecular mechanism of G. elata in vitro and in vivo using PC12 cells and zebrafish model, respectively.Network pharmacology was performed to explore the potential active ingredients and action targets of G. elata Blume extracts (GBE) against depression. The cell viability and proliferation were determined by MTT and EdU assay, respectively. TUNEL assay was used to examine the anti-apoptotic effect of GBE. Immunofluorescence and Western blot were used to detect the protein expression level. In addition, novel tank diving test was used to investigate the anti-depressant effect in zebrafish depression model. RT-PCR was used to analyze the mRNA expression levels of genes.G. elata against depression on the reticulon 4 receptors (RTN4R) and apoptosis-related targets, which were predicted by network pharmacology. Furthermore, GBE enhanced cell viability and inhibited the apoptosis in PC12 cells against CORT treatment. GBE relieved depression-like symptoms in adult zebrafish, included increase of exploratory behavior and regulation of depression related genes. Mechanism studies showed that the GBE inhibited the expression of RTN4R-related and apoptosis-related genes.Our studies show the ameliorative effect of G. elata against depression. The mechanism may be associated with the inhibition of RTN4R-related and apoptosis pathways.

In this paper, a systematic design and high accuracy implementation of fractional order proportional integral (FOPI) controller is proposed for a permanent magnet synchronous motor (PMSM) speed system, and the numerical implementation performance of the fractional order operator is evaluated with comprehensive investigation using different implementation methods. Three commonly used numerical implementation methods of fractional operators are investigated and compared in this paper. Futhermore, for the impulse response invariant method, the effects of different discretization orders on the system control performance are compared. The simulation results show that the high accuracy numerical implementation method of the designed high-order FOPI controller has improved performance over normal accuracy fractional order operation implementation.

Benzophenones (BPs) are a class of UV absorber commonly used in skin care products like sunscreens. With its wide range of application, its environmental and human hazards have received much attention in recent days. Previous studies on the toxicity of BPs mainly focused on its endocrine-disrupting effects, but there are limited studies on its neurodevelopment and neurotoxicity. Herein, using the zebrafish model we studied the neurodevelopmental- and neuro-toxicity of benzophenone 1 (BP1) (0.8, 1.0, 1.2, 1.6, and 2.4 μg/mL). As a result, BP1 led to an increase of embryo mortality, a decrease in hatching rate, and an increase in the rate of developmental abnormalities in a concentration-dependent manner. BP1 also caused developmental defects in the central nervous system (CNS) and dopaminergic (DA) neurons. Accordingly, BP1 injured larval zebrafish general locomotion and response to stimuli in light/dark challenge. In adult zebrafish, BP1 exposure (1, 10, 100, 1000 μg/L) caused inhibition of learning and memory abilities in the T-maze tests, and inhibited exploratory behavior and activity in the novel tank diving tests. Further, transcription levels of genes related to neurotoxicity, neurodevelopment, and anxiety revealed that BP1 may affect the development and function of the myelin sheath, inducing structural and functional defects of CNS, manifested as abnormal behaviors such as anxiety. Hence, the current study revealed the neurodevelopmental toxicity and neurotoxicity of BP1, expanded our knowledge about the toxic effects of BP1 on organisms, posing a possible threat to the environment and human health.

Power dissipation characteristics of Stockbridge dampers (SD) is one of the important indexes in anti-vibration work of transmission line. The study focuses on the optimization of the SD's power dissipation characteristics under the effect of multi-structure parameter coupling. The aeolian vibration of overhead transmission lines is uncertain and random in stochastic dynamics. According to Strouhal formula, the relationship between the vibration frequency of transmission lines and wind speed can be found out. Based on the Weibull wind speed probability distribution, the probability density function of the transmission line conductor and damper coupling system vibration frequency is derived. The SD is considered as a typical 2-dimension of stochastic dynamical system. Based on the random process generated by the power dissipation of the SD, the characteristics of power dissipation and SD's resonant frequencies are analyzed when the multi-structure parameters of the SD are coupled. And the diagrams of the power dissipation at various frequencies are obtained. Based on the probability density function of the vibration frequency of the overhead conductor and damper, the objective function, namely the mathematical expectation of power dissipation (E(PD)), of the optimizations for the SD's power dissipation under the coupling of multiple structural parameters is proposed for the first time according to the author's knowledge. Constraint conditions of the optimizations are built by the quantization processing. The energy dissipation characteristics of the dampers can be evaluated by E(PD), and the power dissipation of SD with different coupled dual structure parameters is optimized based on the proposed method. The optimal values or the optimal value intervals of different coupled dual structure parameters are found, which may provide practical data.

Fluorene-9-bisphenol (BHPF) is a bisphenol A substitute, which has been introduced for the production of so-called ‘bisphenol A (BPA)-free’ plastics. However, it has been reported that BHPF can enter living organisms through using commercial plastic bottles and cause adverse effects. To date, the majority of the toxicologic study of BHPF focused on investigating its doses above the toxicological threshold. Here, we studied the effects of BHPF on development, locomotion, neuron differentiation of the central nervous system (CNS), and the expression of genes in the hypothalamic-pituitary-thyroid (HPT) axis in zebrafish exposed to different doses of BHPF ranging from 1/5 of LD1 to LD50 (300, 500, 750, 1500, 3000, and 4500 nM). As a result, the possible hormetic effects of BHPF on regulating the HPT axis were revealed, in which low-dose BHPF positively affected the HPT axis while this regulation was inhibited as the dose increased. Underlying mechanism investigation suggested that BHPF disrupted myelination through affecting HPT axis including related genes expression and TH levels, thus causing neurotoxic characteristics. Collectively, this study provides the full understanding of the environmental impact of BHPF and its toxicity on living organisms, highlighting a substantial and generalized ongoing dose-response relationship with great implications for the usage and risk assessment of BHPF.

In this paper, researching the correlation property of congenetic subband coefficients of Nonsubsampled Contourlet Transform (NSCT), and proposing a new adaptive denoising theory. This theory combines the excellent shift-invariant of NSCT with the correlation property of congenetic subband coefficients in image denoising. The correlation property contains the entire relational correlation value of the congenetic subband coefficients, and the grey correlation value in single coefficient of the congenetic subband coefficients of the NSCT. According to the correlation property of congenetic subband coefficients, the new algorithm can automatically identify the strong edges, weak edges and noise in the noisy image, and then it can filter the noise and preserve the strong edges and weak edges at certain degree. The experiment results are provided to compare with the elegant non-local means method, which show that the theory proposed in this paper has good effect.

The loose oxide layer on the surface of Ti-6Al-4V titanium alloy can be removed and a dense α-phase layer with the thickness of 11 μm can be produced simultaneously by coupling electrical pulse and ultrasonic treatment (CEPUT). In addition, after CEPUT, the surface grain is refined, the surface roughness is reduced to 0.529 μm, and the surface hardness reaches to 627 HV, showing significant gradient change. During the CEPUT, the processability of the α-phase oxygen-rich layer is improved by the electroplasticity of high peak currents, and the α-phase oxygen-rich layer produces large plastic deformation. Most of the α-phase oxygen-rich layer is removed after the CEPUT, and the remaining coarse α-phase grains are refined to form a dense α-phase layer. The corrosion resistance of the dense oxide layer on the surface has been studied. The results show that the self-corrosion current density of the sample in the NaCl solution decreases to −8.4922E-08 A/cm2 after CEPUT. Compared with the untreated sample, the self-corrosion current density is reduced by two orders of magnitude. The reason for the increased corrosion resistance of titanium alloys may be that the electrolyte is blocked by the dense and intact α-phase layer on the surface and cannot penetrate further into the titanium alloy.

A new method is presented in this article to determine loads on all rollers in a cylindrical roller bearing. By introducing a pair of nonlinear springs for contact of each roller with its inner and outer races, the equations of equilibrium of the multi-component system are established by means of the virtual work principle. A set of linear complementary equations are deduced and solved using the Lemke algorithm for gaps and contact forces between all potentially engaged components. An iterative scheme is employed to effectively deal with the nonlinearity of the Hertzian contact between non-conforming bodies. Numerical results for a 19-roller cylindrical bearing, having various combinations of roller sizes, show that the proposed method is convergent and accurate. With this method, effects of uneven roller sizes caused by manufacturing errors, on load distributions can be accurately and efficiently determined. The proposed method can be extended to deal with other types of manufacturing errors such as uneven roller angular spacing, eccentricity, ovality, friction, etc., which are of significant interest to the bearing manufacturers.

There are always some differences in the diameters of the rolling elements that are less than manufacturing tolerance, which are known as off-sized defects. These diameter differences of the rolling elements assumed to be with identical size in the traditional bearing analysis affect the load performance of the bearing greatly and make the evaluation of the load distribution in the bearing difficult. In this study, a static model was developed to investigate the effects of diameter differences among cylindrical rollers on the load performance in a bearing. In the model, the diameter and order of each roller were defined arbitrarily. Contact judgments between all the rollers and the raceways were done constantly in the solution process, so that compatibility of deformation of the rollers and raceways need not be considered, which was different from other traditional methods. The effects of roller off size and its arrayed order in the bearing on the load distribution were analyzed. It was found that the effect of one off-sized roller on the load distribution was serious. Also, equal space or ordinal array of the multiple or full off-sized rollers was much better than random array. Furthermore, the relative diameter of the rollers determined the load distribution in the bearing. This article can help to further study the dynamic performance of the bearing with the off-sized cylindrical roller in the future.