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Currently, the borescope is the most used method with non-destructive testing in the process of aero-engine inspections and is the only way to obtain borescope images. In recent years, the artificial intelligence technologies such as deep learning are applied to aero-engine damage classification and detection, and some effective methods are proposed to achieve intelligent inspection of aero-engines, which have significant value for industrial applications. The benefits and disadvantages of aero-engine borescope inspection and its development are reviewed. The progress in the application of artificial intelligence technologies such as expert system and machine learning to engine borescope detection images is over-viewed. Some of the challenges in achieving intelligent aero-engine borescope inspection are summarized.

Hormone replacement therapy (HRT) is not recommended for treating learning and memory decline in menopausal women because it exerts adverse effects by activating classic estrogen receptors ERa and ERp. The membrane estrogen receptor G protein-coupled receptor 30 (GPR30) has been reported to be involved in memory modulation; however, the underlying mechanisms are poorly understood. Here, we found that GPR30 deletion in astrocytes, but not in neurons, impaired learning and memory in female mice. Astrocytic GPR30 depletion induced A1 phenotype transition, impairing neuronal function. Further exploration revealed that Praja1 (PJA1), a RING ubiquitin ligase, mediated the effects of astrocytic GPR30 on learning and memory by binding to Serpina3n, which is a molecular marker of neuroinflammation in astrocytes. GPR30 positively modulated PJA1 expression through the CREB signaling pathway in cultured murine and human astrocytes. Additionally, the mRNA levels of GPR30 and PJA1 were reduced in exosomes isolated from postmenopausal women while Serpina3n levels were increased in the plasma. Together, our findings suggest a key role for astrocytic GPR30 in the learning and memory abilities of female mice and identify GPR30/PJA1/Serpina3n as potential therapeutic targets for learning and memory loss in peri- and postmenopausal women., Introduction The process of learning and memory is how people acquire, encode, store, retain and later retrieve information in the brain. For perimenopausal women, learning and memory abilities decline rapidly [...]

Surface plasmon polaritons (SPPs) have become a research hotspot due to their high intensity and subwavelength localization. Through free-electron excitation, a portion of the momentum of moving electrons can be converted into SPPs. Converting highly localized SPPs into a radiated field is an approach with the potential to aid in the development of a light radiation source. Reducing losses of SPPs is currently a critical challenge that needs to be addressed. The lifetime of SPPs in metal films is longer than that in metal blocks. Traditional optical gratings can transform SPPs into radiation to avoid the decay of SPPs in metal; however, they are created by etching metal films, so they tend to alter the dispersion characteristics of these films and will emit radiation in the direction perpendicular to the metal surface. This paper proposes an approach to converting the SPPs of a metal film excited by free electrons into a radiation field via lateral grating and obtaining in-plane radiation. We investigate the properties of SPP lateral radiation. The study of lateral radiation from metal films holds significant importance for SPP radiation sources and SPP on-chip circuit development. [ABSTRACT FROM AUTHOR]

As one of the most intact areas in the downstream of the Sanjiang Plain, Fuyuan is a key development area relying on the policy of "one island and two countries". Since 2000, the land use structure of Fuyuan has changed significantly due to natural and human factors. In this paper, We useed MARKOV to simulate LUCC ( Land-Use and Land-Cover Change) in Fuyuan from 2000 to 2020, calculating land use dynamic index , doing some correspondence analysis, and exploring its driving force factors. The results show that some land types are changed more violently. We analyzed the difficulty degree of land type mutual transformation, and the result is that the conversion of residential and other construction land is high, and the ecological reversibility is poor. Forest swamps and woodlands are most easily converted into cultivated land, and the competition is strong. Wetland is easy to convert into transport land; Fallow is the easiest way to estore wetlands. On this basis, we analyzed the natural factors and policy changes in the past 20 years, and concluded that human factors are the main driving forces for LUCC( Land-Use and Land-Cover Change),such as the urbanization process in Fuyuan and the implementation of policies about ecologically desertification and development of foreign trade, etc.

In this study, lactic acid bacteria (LAB) with producing γ-aminobutyric acid (GABA) were screened from traditional pickled vegetables in Northeast China using thin-layer chromatography (TLC) and the Berthelot colorimetric method. LAB were identified by the physiological and biochemical test and 16S rRNA sequencing analysis. And then their biological properties, including acid tolerance, bile salt tolerance, antioxidant, antibacterial activity, antioxidant activity and acid production rate, were analyzed using principal component analysis (PCA). These results showed that five strains LAB with typical GABA-producing were obtained from forty strains LAB from traditional pickled vegetables, including one strain Weissella kandleri HJL2 and four strains Lactobacillus plantarum PJ-7, HJG1-3, L-9, and L-11. Among them, L. plantarum PJ-7 isolated from fermented radish had better ability to synthesize GABA, and the yield reached 0.48 mg/mL. There were significant differences in acid tolerance, bile salt tolerance, antioxidant and other biological characteristics of the five strains LAB. Based on PCA, L. plantarum PJ-7 ranked the first in the comprehensive score of biological characteristics. Therefore, L. plantarum PJ-7 has excellent GABA synthesis ability and good biological characteristics, which would provide a theoretical basis for the development of GABA-rich pickled vegetables. [ABSTRACT FROM AUTHOR]

In this study, we synthesized three low-sulfur and low-phosphorus ionic liquids (ILs). These were N88816P8, P88816P8, and P88816DOSS. The viscosity and thermal stability of the three ILs were analyzed. The tribological properties and lubrication mechanisms of the three ILs were investigated as lubricants for a carbide ball–Inconel 690 nickel-based alloy friction pair and compared at 50 °C and 150 °C. The wear spots of the carbide ball and nickel-based alloy disc samples were characterized using SEM and EDS. The experimental results revealed that P88816P8 had excellent tribological properties. The lubrication mechanism of P88816P8 as a lubricant for the carbide ball–Inconel 690 nickel-based alloy friction pair was investigated using XPS. The excellent friction reduction and anti-wear properties of P88816P8 could be attributed to the tribo-chemistry between P88816P8 and Inconel 690 as well as the formation of a tribo-film on the wear-spot surface. This high-performance IL, suitable for carbide ball–Inconel 690 contact, will be applied to a cutting process of Inconel 690. [ABSTRACT FROM AUTHOR]

This study prepared copper (Cu) matrix composites with different graphene contents (0∼1.0 wt-%) and an equal amount of alumina (Al2O3) whisker by vacuum hot pressing sintering. The microstructures of the Cu/C and Cu/Al2O3 interfaces were characterised. The electrochemical corrosion behaviour of the composites was evaluated to study the influence of graphene content on the corrosion performance of the Cu matrix composites. The results showed that incorporating uniformly dispersed graphene with a small amount (∼0.25 wt-%) enables close integration with the Cu matrix, slows down the corrosion rate, and increases the impedance of the composites, thus effectively improving the corrosion resistance of Cu matrix composites. With an increase in graphene content (∼1.0 wt-%), defects tend to generate, leading to the formation of multiple corrosive microcell cavities in the composite, thus accelerating the corrosion of the composite. The Gr/Cu-0.25 composite exhibited better corrosion resistance in acidic, neutral, and alkaline corrosive solutions. [ABSTRACT FROM AUTHOR]