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In order to study the crack damage propagation law of rotor blades under complex loads in the actual service of aero-engines, the crack propagation life curve of blades was constructed based on the operational data of aero-engine, and the crack propagation rate formula was established by fracture mechanics theory. Taking the high-pressure compressor blade as an example, the load model of the compressor blade structure was constructed by the fluid-solid coupling method. The Paris， Walker and Newman crack growth rate formulas were used to analyze the three-dimensional crack propagation in the tip region of the compressor blade. The simulation results show that the prediction results of the three crack propagation rate formulas are consistent with the crack propagation curve of the engine operation data in the early stage of crack propagation, which can better describe the crack propagation law of the blade. In the stage of stable crack propagation, the prediction results of Walker and Newman formulas are relatively dangerous, and the prediction results of Paris formula are in good agreement with each other, and can be mutually confirmed with the requirements of damage development control in the manufacturer's technical manual.

A modified 5 000 m3/d sewage treatment station would be built in a town of Beijing, the main source of sewage contained domestic sewage and industrial wastewater. The designed influent water quality took measured water quality and designed water quality of the present sewage treatment station as the reference, while the effluent water quality was required to meet Level B of the Discharge Standard of Water Pollutants for Municipal Wastewater Treatment Plants (DB 11/890-2012). Considering factors such as land occupation, operation management, treatment effect, construction cycle and project investment, etc., the progress of anaerobic-anoxic-oxic+moving bed biofilm reactor (AAO+MBBR)+high density sedimentation tank+cloth media filter was selected, with comparing different secondary treatment processes and advanced treatment processes. Most of the process structures employed integrated devices. The investment of the station, water treatment cost per ton, and the influent/effluent water quality indices in real operation were introduced in detail. After the completion of the project, an 8-month actual operation showed that the effluent qualities met the level B of the Discharge Standard of Water Pollutants for Municipal Wastewater Treatment Plants (DB 11/890-2012) completely, providing experience for the construction of similar sewage treatment stations.

[Objective] We aim to establish an efficient and stable genetic transformation system of Lycium ruthenicum and reduce the vitrification rate of the regenerated seedlings in order to promote gene function study and genetic improvement. [Methods] L. ruthenicum leaves were used as explants and Agrobacterium (LBA4404, EHA105) was used to transform L. ruthenicum. By adjusting the types of basic medium and adding plant hormones, we selected the optimal callus-induction medium, differentiation and selection medium, and rooting-induction medium. The transformation rate of L. ruthenicum was increased to over 65%, while the seedling vitrification rate was decreased to below 10%. This combined culture system laid a foundation for the molecular breeding of L. ruthenicum. [Results] (1) The optimal infection concentration of Agrobacterium (OD600) was 0.6 and the infection time was 25 min for the combined culture system of L. ruthenicum. Under this condition, the callus-induction rate was 78.2%-96%; (2) The optimal differentiation and selection medium contained: MS+inositol 50 mg/L+nicotinic acid 0.25 mg/L+vitamin B6 0.25 mg/L+Fe salt storage solution 1 mL/L+glycine 1.0 mg/L+ vitamin B1 0.05 mg/L+6-BA 0.25 mg/L+sucrose 30 g/L+agar 6 g/L+Kanamycin 30 mg/L+Timentin 300 mg/L, pH 6.0. The optimal rooting medium contained: WPM+IBA 0.25 mg/L+sucrose 30 g/L+agar 6 g/L +Kanamycin 30 mg/L+Timentin 300 mg/L, pH 6.0. (3) On the optimal differentiation and selection medium, the seedling vitrification rate infected by Agrobacterium LBA4404-pBI121 was about 65%, while that infected by Agrobacterium EHA105-pBI121 was below 10%. (4) The rooting efficiency of the regenerated seedlings reached 81.2% using a low-salt WPM medium of woody plants. (5) The ratio of the positive callus to the total number of inoculated leaves was used to evaluate the transformation efficiency. Using the optimal transformation system, the transformation rates of Agrobacterium LBA4404-pBI121 and EHA105-pBI121 were 51% and 65.2%, respectively. [Conclusion] The combined culture system of L. ruthenicum leaves can improve transformation rate while reducing seedling vitrification rate.

In this article, we focus on the current status and problems regarding the basic capabilities of the frontier new materials industry in cutting-edge fields such as brain-like intelligence, artificial intelligence, deep space exploration, network security, and efficient energy conversion. Considering the phased development plans in 2025 and 2035, we propose the development goals and strategies for promoting the basic capabilities of China’s frontier new materials industry in terms of scientific and technological innovation, support, competitiveness, sustainable development, infrastructure construction, and industrial ecological environment. To meet the requirements of the new round of scientific and technological revolution and industrial transformation for frontier new materials, countermeasures and suggestions are proposed from the following aspects: material genetic engineering, double circulation, carbon peak and carbon neutrality, and testing and characterization of independent frontier new materials.

In response the issues of large parameter quantity, high commitational complexity, and difficulty in deploying the existing defect detection algorithms on embedded devices with limited computing resources, an improved lightweight fabric defect detection algorithm SSPY based on YOLOv5s was proposed. Firstly, the ShuffleNetv2 network was used as the backbone feature extraction network to achieve lightweight model. The SimAM no-parameter attention mechanism was introduced in the backbon network and small target detection layer, enhancing the feature extraction capabilities of the algorithm without adding additional parameters. Model compression was further achieved by pruning based on the importance of the convolution kernel in the sparse training evaluation feature extraction layer. Finally, the SSPY algorithm was deployed on Rockchip RK3568 platform, and the deployment of the fabric defect real-time detection algorithm was completed on embedded devices. Multiple comparison experiments were carried out on fabric defect data set. Experimental results show that compared with Y0L0v5s, SSPY's mAP increases by 0.8% and the number of parameters decreases by 80. 3%. When SSPY was deployed on RK3568, the running speed can reach 49 FPS, which met the needs of real-time performance and embedded device deployment of fabric defect detection algorithms in industrial applications. [ABSTRACT FROM AUTHOR]

In recent years, lithium metal plays an irreplaceable role in the preparation of all-solid-state lithium batteries and aluminum-lithium alloys; but the cost of lithium metal production is still a problem that needs to be solved by production enterprises. Therefore, this paper optimizes the production process and equipment from the perspective of reducing energy consumption by using Solid Works three-dimensional modeling of the electrolyzer structure as well as ANSYS simulation and simulation software to simulate the thermal field of the electrolyzer and calculations, resulting in the optimal design scheme. Its production electrolysis efficiency can reach 91%, energy consumption is below 35 kWh/kg, chlorine extraction and lithium collection device can run automatically, the concentration of extracted chlorine gas is 90%, the lithium collection efficiency can reach more than 80%, and the amount of lithium is more stable. The equipment can be better put into industrialized production, meet the needs of enterprises to reduce production costs, and promote the development of molten salt electrolysis of lithium metal industry. [ABSTRACT FROM AUTHOR]

Abnormal changes of the nasolabial sulcus characteristics are important symptoms of stroke, usually as the basis for the stroke facial diagnosis by traditional Chinese medicine with naked-eye observation. In order to quantify the characteristics of nasolabial sulcus and to solve the problem that it is difficult to find fine feature changes and difficult to communicate information in traditional Chinese medicine facial diagnosis, the polarization parametric indirect macroscopic imaging (PIMI) method was adopted by using the Stokes St parametric image. The nasolabial sulcus characteristics of healthy people, stroke patients, and prognostic people were obtained. The results show that the nasolabial sulcus St data of healthy people has good symmetry, while it is obviously asymmetrical for the stroke patients, and the difference between the left and right peaks is more than 20. It becomes more symmetrical when the stroke patient gets better. This method is expected to be applied to the digital diagnosis of stroke diseases and the evaluation of the treatment process, promoting the development of digital Chinese medicine. [ABSTRACT FROM AUTHOR]

With the emergence of concepts such as metaverse and Web3.0, blockchain plays a very important role in many fields. Cross-chain technology is an important technical means to achieve inter-chain interconnection and value transfer. At this stage, traditional cross-chain technologies such as notary and sidechain have trust issues. At the same time, in the field of cross-chain identity authentication, there are problems that the identities of each chain are not unified and users do not have control over their own identities. Firstly, it systematically summarizes the development process and technical solutions of digital identity and cross-chain technology, and analyzes and compares four digital identity models and nine mainstream cross-chain projects. Secondly, by analyzing the main research results of cross-chain identity authentication in recent years, a general model of cross-chain identity authentication is designed, and the shortcomings of existing solutions are summarized. Then, it focuses on the cross-chain identity authentication implementation scheme based on DID, and analyzes the technical characteristics, advantages and disadvantages of different solutions. On this basis, three DID-based cross-chain identity authentication models are summarized, the main implementation steps are functionally described, and their advantages, limitations and efficiency are analyzed. Finally, in view of the shortcomings of the current DID-based cross-chain identity authentication model, its development difficulties are discussed and five possible future research directions are given.

Objective: To study the clinical anatomy of the sphenopalatine foramina by dissecting the sphenopalatine foramina during Vidian nerve branch neurotomy. The anatomy and CBCT images of sphenopalatine foramen were analyzed to facilitate the navigational of clinical operation using CBCT images. Methods: From October 2017 to September 2023, 84 cases（168 sides） of Vidian nerve branch neurotomy in our department were collected. The clinical summary was made according to the anatomy of sphenopalatine foramen during the operation. Preoperative CBCT imaging findings of the sphenopalatine foramina were also studied. Results: The clinical anatomy of sphenopalatine foramen could be divided into four types: middle meatus type（1.19%）, trans-meatus type（62.29%）, superior meatus type（33.33%） and double foramen type（1.19%）. The incidence of ethmoidal ridge was 98.81%. The distance from sphenopalatine foramina to posterior nasal canal were（14.63±2.66） mm to left and（14.65±2.63） mm to right, The position Angle ∠a of lower margin of sphenopalatine foramina were（62.36±10.05）° to left and（61.51±11.82）° to right, respectively. Axial CT images can be used to divide the sphenopalatine foramen into five levels: the upper edge of the sphenopalatine foramen level, the Vidian nerve level, the basal plate interaction level, the lower edge of the sphenopalatine foramen level and the pterygopalatine canal level. The agreement between endoscopic anatomy of sphenopalatine foramen and imaging navigation was 100%. Conclusion: The sphenopalatine foramina exhibit various anatomical types. The preoperative navigational CBCT reading can effectively identify the type of sphenopalatine foramina, guide the choice of surgical method, and help avoid serious complications. This has significant clinical application value., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To evaluate the medium-term results of uncemented acetabular revision with impacted deep frozen morselized allografts., Methods: From April 1995 to December 2001, 58 cases (62 hips) were performed acetabular revision by use of deep frozen morselized allograft firmly impacted into localized defects as well as the entire acetabular cavity, followed by insertion of a uncemented cup with supplementary screw fixation. There were 32 males (34 hips) and 26 females (28 hips), with age of (49.6 +/- 15.4) years old. Among 62 hips, 32 hips involved in left side and 30 hips involved in right side. The cause of revision was aseptic loosening of the cup in 56 hips, septic loosening of the cup in 3 hips, and polyethylene liner dislodging with severe acetabular osteolysis in 3 hips. The average interval between the primary total hip arthroplasty and the revision was (10.1 +/- 3.9) years. According to the American Academy of Orthopaedic Surgeons classification, 42 hips belonged to type II and 20 hips to type III acetabular defects. The clinical and radiographic results were analyzed postoperatively., Results: All wounds healed by first intention. No deep venous thrombosis and infection occurred postoperatively. All patients were followed up 6-13 years (average 8.1 years). The Harris score was improved from 61.1 +/- 10.2 preoperatively to 92.0 +/- 7.3 postoperatively, showing significant difference between preoperation and postoperation (P < 0.05). The results were excellent in 46 hips, good in 10 hips, fair in 4 hips, and poor in 2 hips, the excellent and good rate was 90.3%. The time for allograft incorporation was (12.5 +/- 4.4) months after operation. The annual polyethylene liner wear rate was (0.13 +/- 0.09) mm. Linear and cavitary osteolysis was observed in 2 and 12 hips, respectively. Heterotopic ossification developed in 7 hips (11.3%); 3 hips were rated as grade I, 3 as grade II, and 1 as grade III according to Brooker classification. One cup underwent revision for aseptic loosening and 2 were defined as radiographic failures. Kaplan-Meier survival rate of the cup was 94.2% +/- 3.3% at 8 years after operation., Conclusion: The combination of uncemented cup component with deep frozen morselized allografts seems to be a reliable solution for restoring bone stock, relocating the hip center, and stabilizing the cup in acetabular revision, and provides favorable medium-term clinical and radiographic results.

Objective: To establish a method of examining acrylamide in cooked popcorn., Methods: Solid phase extraction/gas chromatography (SPE/GC) was established with N, N-dimethyl acrylamide as internal standard., Results: The detection limit and the quantification limit were estimated at 3 microg/L and 10 microg/L, respectively, and the linear correlation coefficient was 0.9969. Seven commercial popcorn samples with different flavors were collected and tested in this paper. The RSD of acrylamide level of caramel sweet popcorn microwaved was 1.95 % (n = 6). When the commercial popcorns of caramel sweet and cream salted were microwaved (A and D) or conventional heated (A' and D'), the acrylamide levels reached [Am]A = 1017 microg/kg, [Am]D = 146.5 microg/kg, [Am]A, = 2206 microg/kg and [Am]D = 970.1 microg/kg, respectively., Conclusion: The microwaved popcorns tested are safer in general because the acrylamide level of them except that with high simple sugar content is obviously lower than that of ordinarily heated one.