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The signal of small defects in steel wire rope is often submerged in wave noise. Therefore, it is difficult to detect small defects in wire rope and easy to miss detection. In order to solve this problem, a steel wire rope defect magnetic flux leakage detection method based on improved complementary ensemble empirical mode decomposition (ICEEMD) is proposed. To avoid the influence of the lubricant or dust on the surface of the wire rope on the detection signal, the electromagnetic detection method is adopted. CEEMD-WTF-WF multi-stage noise reduction method is obtained by combining ICEEMD, wavelet threshold filtering (WTF) and Wiener filtering (WF). The intrinsic mode function (IMF) component is obtained by decomposing the magnetic flux leakage signal of steel wire rope through ICEEMD. The energy ratio, permutation entropy and cross-correlation coefficient of IMF components are calculated. The IMF trend component and IMF stock noise component are extracted. WTF is conducted on the stock noise component to filter the useful IMF component reconstruction signal. WF is applied to the reconstructed signal to remove random noise. The eigenvalues of the de-noised defects are extracted, input and trained by BP neural network. The magnetic flux leakage signals of the steel wire rope defects are identified. The experimental results show that ICEEMD-WTF-WF multi-stage noise reduction method has good noise reduction effect on the magnetic flux leakage signal of steel wire rope. The SNR and kurtosis indexes are better than those of WTF, moving average filter and WF. The BP neural network model based on ICEEMD-WTF-WF takes a short time to detect. The average accuracy rate of small defects reaches 98.13%, which can better meet the requirements of wire rope defect detection.

ObjectiveThe purpose of this study is to explore the mechanism of electroacupuncture at Baihui and Shenting acupoints to alleviate cerebral ischemia-reperfusion injury by regulating BNIP3L-mediated mitophagy.MethodsA total of 60 SD rats were randomly divided into sham operation group (n=15) and operation group (n=45) by using the random number table method. Only the blood vessels were separated and exposed in the sham operation group, without ligation and no nylon thread inserted. The rats in the operation group were treated with the middle cerebral artery occlusion (MCAO) method to prepare the focal cerebral ischemia-reperfusion (I/R) model, and the Zea Longa method was used to score the neurological function 2h after the operation. Finally, 30 rats were included in the operation group. The included operation group rats were further randomly divided into the model group, electroacupuncture group, and electroacupuncture+3-MA group, with 10 rats in each group. After grouping, each group was treated with different methods such as electroacupuncture for 7 days, and the Zea Longa method was used to evaluate the neurological function again on the 1, 3, 5, and 7 days. After 7 days of intervention, the left cerebral cortex tissue of each group was obtained, hematoxylin-eosin (HE) staining was used to observe the pathological changes of the brain tissue, the expression level of LC3-Ⅱ/LC3-Ⅰ protein was detected by Western blot, and the tissue immunofluorescence technology was applied to detect the expression and colocalization of mitophagy-related protein BNIP3L and SQSTM1 labeled. The TUNEL method detected the apoptosis rate of rat nerve cells in each group.Results1) The neurological scores of the rats in the operation group were significantly increased 2 hours after the MCAO, and the rats in the sham-operation group did not show symptoms of neurological deficit. On the 7th day after the intervention, the neurological scores of the rats in the model group and the electroacupuncture+3-MA group still increased significantly, which were significantly different from those in the sham operation group (PPPPPP

Aiming at the problems of faults, precipitation, weak layers and other factors inducing the deformation and instability of the end slope of the open-pit mine, taking the north slope of Dongming Open-pit Mine as the engineering practice background, the method of combining numerical simulation theory and limit equilibrium analysis is used. The influence of the weak layer of the north side slope on the deformation and displacement law of the slope rock and soil, and at the same time, combined with the limit equilibrium analysis method to control the stability of the north side slope, two schemes are proposed, namely, slope cutting and load reduction + pressure reduction. Through analysis and research, and based on the calculation results of Geo-slope and engineering geological conditions, the plan of slope cutting and load reduction + presser foot is finally adopted, which provides a reference for safe and efficient production during actual mining.

Aiming at the problem that the attitude sensor of the quadrotor was susceptible to interference, resulting in large attitude output errors, a multi-sensor quadrotor attitude control system based on STM32 was designed. The system used sensors such as MPU6050 to collect the attitude data of the quadrotor in real time, calculated the attitude through the quaternion complementary filtering algorithm, and used the cascade PID control to drive the motors in PWM mode. Based on the design of the software and hardware of the system, the physical production and flight test of the quadrotor were completed. The results show that the system can flexibly control the attitude of the quadrotor UAV and realize the stable flight of the quadrotor UAV.

The reform of property right system of natural resources is the only way to promote the construction of ecological civilization in China. By systematically combing the construction process of China’s natural resources assets property rights system and drawing lessons from foreign property rights system experience, this paper can systematically analyze the main problems faced by China’s natural resources assets system at present, and put forward targeted policy suggestions for reform.

Metaheuristic algorithms are widely used in engineering problems due to their high efficiency and simplicity. However, engineering challenges often involve multiple control variables, which present significant obstacles for metaheuristic algorithms. The Crested Porcupine Optimizer (CPO) is a metaheuristic algorithm designed to address engineering problems, but it faces issues such as falling into a local optimum. To address these limitations, this article proposes three new strategies: composite Cauchy mutation strategy, adaptive dynamic adjustment strategy, and population mutation strategy. The three proposed strategies are then introduced into CPO to enhance its optimization capabilities. On three well-known test suites, the improved CPO (CAPCPO) outperforms 11 metaheuristic algorithms. Finally, comparative experiments on seven real-world engineering optimization problems demonstrate the advantages and potential of CAPCPO in solving complex problems. The multifaceted experimental results indicate that CAPCPO consistently achieves superior solutions in most cases. [ABSTRACT FROM AUTHOR]

We experimentally demonstrated the fabrication of asymmetric long-period fiber gratings (LPFGs) in thin core fiber by use of focused CO 2 laser beam. The proposed device exhibits a high extinction ratio of over 25 dB at the resonant wavelength and a narrowed 3-dB bandwidth of only 8.7 nm, which is nearly one order of magnitude smaller than that of LPFGs in conventional single-mode fibers. It also exhibits a high polarization-dependent loss of over 20 dB at resonant wavelength. The temperature and external refractive index (RI) sensitivity of the proposed structure are measured to be 46 pm/°C, within a temperature range from 25 °C to 100 °C, and 1047.3 nm/RIU, within the RI range from 1.400 to 1.440, respectively. The temperature induced error is ∼8% for RI measurement. Such long LPFGs may find potential applications of highly sensitive RI sensors in the fields of chemical and biomedical sensing. [ABSTRACT FROM PUBLISHER]

We demonstrate a high-sensitivity gas pressure sensor by use of an in-fiber Fabry–Pérot interferometer (FPI) based on hollow-core photonic bandgap fiber (HC-PBF) with a side-opened channel. The FPI was constructed by splicing a thin piece of HC-PBF between two stander single-mode fibers. Then, a side-opened channel was drilled through the hollow core of the HC-PBF by use of a femtosecond laser. Such an FPI with a side-opened channel greatly enhanced the gas pressure sensitivity up to 4.24 nm/MPa, which is two orders of magnitude higher than that of FPI with an enclosed cavity. In addition, the effects of cavity length on the gas pressure sensing performance were also studied. A shorter cavity gives rise to broader measurement range while offering larger detection limit, and vice versa. The structure size is tens of micrometers, which makes it possible to develop an ultracompact high-sensitivity gas pressure sensor. [ABSTRACT FROM PUBLISHER]

Total alkaloids in Rubus aleaefolius Poir (TARAP) is a folk medicinal herb that has been used clinically in China to treat nonalcoholic fatty liver disease (NAFLD) for many years. However, the mechanism of its anti-NAFLD effect is largely unknown. In this study, we developed a NAFLD rat model by supplying a modified high-fat diet (mHFD) ad libitum for 8 weeks and evaluated the therapeutic effect of TARAP in NAFLD rats as well as the underlying molecular mechanism. We found that TARAP could reduce the serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein (LDL-C) levels and increase the serum high-density lipoprotein (HDL-C) level in NAFLD rats. In addition, TARAP treatment reduced expression of fatty acid synthetase (FAS), and acetyl-CoA carboxylase (ACC) and upregulated the expression of carnitine palmitoyltransferase (CPT). Our results suggest that regulation of lipid metabolism may be a mechanism by which TARAP treats NAFLD.

We aimed to explore the anti-inflammatory effects of total alkaloids inRubus alceifolius Poir [corrected]. (TARAP) on non-alcoholic fatty liver disease, and to investigate the possible molecular mechanisms. A rodent non-alcoholic fatty liver disease (NAFLD) model was established by administration of a modified high-fat diet ad libitum for 8 weeks. Rats were treated with polyene phosphatidylcholine (PP), TARAP low‑dose (0.72 g/kg body weight/day) and TARAP high-dose (1.44 g/kg body weight/day). The model group and the control group received distilled water. After treatment for 4 weeks, the blood samples were obtained from the abdominal aorta, and the levels of serum ALT, AST, GGT, ALP, TG, TC, HDL-C and LDL-C were measured. Changes in liver tissue morphology were evaluated by H&E staining. The expression levels of nuclear factor (NF)-κB, cyclooxygenase-2 (COX‑2), interleukin (IL)-6 and tumor necrosis factor (TNF)-α in rat livers were assayed by reverse transcription‑polymerase chain reaction (RT-PCR) and immunohistochemistry. Both TARAP and PP attenuated hepatic steatosis induced by the high-fat diet. The modified high-fat diet caused a significant increase in ALT, AST, GGT, ALP, TG, TC, LDL-C levels and a decrease in HDL-C levels. TARAP and PP treatment abrogated the increase in the levels of liver enzymes and the levels of TG, TC, LDL-C, as well as suppressed the increase in HDL-C levels. The results of RT-PCR and immunohistochemical assay showed that PP and TARAP treatment decreased the expression of NF-κB, COX-2, IL-6 and TNF-α. In conclusion, these results suggest that TARAP may protect against NAFLD through regulation of the NF-κB pathway.