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The precipitation behavior of secondary α phase and mechanical properties of high strength TB9 titanium alloy were investigated during single aging and duplex aging. The alloy phase constitution was analyzed by XRD，and the microstructure was observed by optical microscopy and scanning electron microscopy. The evolution characteristics of the microstructure with aging temperature were mainly analyzed. The room temperature tensile properties and fracture toughness were tested. The research results indicate that during single aging，secondary α phase exhibits serrated and layered precipitation. With increasing aging temperature，the size of α phase increases，and the content of layered α phase increases. The strength at 430 ℃ aging is lower and the plasticity is higher. The strength at 470 ℃ aging is the highest. With increasing aging temperature，the strength first increases and then maintains at the similar level. During duplex aging，most of secondary α phases precipitate in a serrated shape within the grains. With increasing aging temperature，the size of α phase increases，the tensile strength first increases and then decreases，reaching a maximum of 1542 MPa. The tensile strength of duplex aging is significantly higher than that of single aging，which is mainly due to the combined strengthening effect of second phases near grain boundaries and intragranular α phases with serrated shape.

There are many unmeasurable branches along with distribution lines. The sensitivity and speed of traditional three-stage overcurrent protection lacks when applied to these lines. Even the phasor differential protection cannot identify internal faults sensitively to maintain sufficient safety under external faults. With 5G communication is penetrating the field of power grid automation, a comprehensive protection scheme for branched distribution lines is proposed. Firstly, analyze negative sequence currents phase characteristics under internal or external faults, and negative-sequence current phase-comparison protection is proposed. Secondly, in some harsh working conditions, 5G communication's synchronization cannot be guaranteed, or even out of step. A positive sequence amplitude differential protection is introduced. Finally, the three-stage overcurrent protection is combined to form a complete set of protection coordination schemes when communication interruption or some extreme situations. A 10 kV active distribution network model is built in PSCAD/EMTDC to verify the proposed protection criteria and scheme. The simulation results demonstrate the effectiveness of the proposed protection criteria and scheme.

In order to realize the safety, high efficiency and high recovery rate mining of 9-13 m thickness hard coal seam in Jinjitan Coal Mine, the top coal recovery rate and coal wall stability of different cutting heights are analyzed by theoretical analysis and numerical simulation. Based on the corresponding relationship between top coal recovery rate, coal wall stability and cutting height, a super large mining height and small mining and drawing ratio technology which based on mining and supplemented by releasing is proposed. The ZFY21000/35.5/70D two pillar shield hydraulic support with super large mining height is developed. Based on the optimization design of anti impact column and high-efficiency caving mechanism, the problems of easy impact of super high mining height fully mechanized top coal caving face, easy rib spalling of coal wall and easy arching of hard coal are solved. Fully mechanized top coal caving mining with super high mining height and small mining and caving ratio is an effective way to improve recovery rate and realize high yield and high efficiency of extra thick hard coal.

Background: Recent studies have demonstrated the relevance of circulating factors in the occurrence and development of colorectal cancer (CRC); however, the causal relationship remains unclear. Methods: Summary-level data for CRC were obtained from the UK Biobank (5,657 cases and 372,016 controls), FinnGen cohort (3,022 cases and 215,770 controls), and BioBank Japan Project (BBJ, 7,062 cases and 195,745 controls). Thirty-two peripheral markers with consistent definitions were collected from the three biobanks. Mendelian randomization (MR) was used to evaluate the causal effect of circulating factors on CRC. The effects from the three consortiums were combined using trans-ancestry meta-analysis methods. Results: Our analysis provided compelling evidence for the causal association of higher genetically predicted eosinophil cell count (EOS, odds ratio [OR], 0.8639; 95% confidence interval [CI] 0.7922–0.9421) and red cell distribution width (RDW, OR, 0.9981; 95% CI, 0.9972–0.9989) levels with a decreased risk of CRC. Additionally, we found suggestive evidence indicating that higher levels of total cholesterol (TC, OR, 1.0022; 95% CI, 1.0002–1.0042) may increase the risk of CRC. Conversely, higher levels of platelet count (PLT, OR, 0.9984; 95% CI, 0.9972–0.9996), total protein (TP, OR, 0.9445; 95% CI, 0.9037–0.9872), and C-reactive protein (CRP, OR, 0.9991; 95% CI, 0.9983–0.9999) may confer a protective effect against CRC. Moreover, we identified six ancestry-specific causal factors, indicating the necessity of considering patients' ancestry backgrounds before formulating prevention strategies. Conclusions: MR findings support the independent causal roles of circulating factors in CRC, which might provide a deeper insight into early detection of CRC and supply potential preventative strategies. [ABSTRACT FROM AUTHOR]

The swim bladder in some teleost fish functions to transfer the sound energy of acoustic stimuli to the inner ears. This study uses the auditory evoked potential tests, micro-computed tomography scanning, reconstruction, and numerical modeling to assess the contribution of the swim bladder to hearing in crucian carp (Carassius carassius). The auditory evoked potential results show that, at the tested frequency range, the audiogram of fish with an intact swim bladder linearly increases, ranging from 100 to 600 Hz. Over this frequency, the sound pressure thresholds have a local lowest value at 800 Hz. The mean auditory threshold of fish with an intact swim bladder is lower than that of fish with a deflated swim bladder by 0.8–20.7 dB. Furthermore, numerical simulations show that the received pressure of the intact swim bladders occurs at a mean peak frequency of 826 ± 13.6 Hz, and no peak response is found in the deflated swim bladders. The increased sensitivity of reception in sound pressure and acceleration are 34.4 dB re 1 μPa and 40.3 dB re 1 m·s−2 at the natural frequency of swim bladder, respectively. Both electrophysiological measurement and numerical simulation results show that the swim bladder can potentially extend hearing bandwidth and further enhance auditory sensitivity in C. carassius. [ABSTRACT FROM AUTHOR]

The electro-hydrostatic actuator (EHA) is a highly integrated and reliable actuation system which has been widely used in aerospace and construction machinery. In addition, the direct load sensitive EHA (DLS–EHA) has been investigated by introducing load-sensitive techniques which can well match the system output and external loads. More importantly, the matching design of motor–pump parameters is an important stage in the pre-design phase of DLS–EHA. For this reason, a multi-objective optimization design method for DLS–EHA motor–pump parameters is proposed in this paper. Firstly, the motor–pump mass and energy loss models are constructed based on similarity criteria. Secondly, the multi-objective particle swarm optimization algorithm (MOPSO) is used to optimize the design of the motor-pump parameters, and the Pareto frontier solutions of the optimized parameters are obtained. Further, the optimal design parameters are selected on the basis of meeting the actual requirements. Finally, the DLS–EHA prototype is designed based on the optimized design parameters and experimental verification is completed. The results of the study show that the optimized design parameters can meet the design requirements. The design method proposed in this paper provides an important theoretical basis for the optimized design of DLS–EHA. [ABSTRACT FROM AUTHOR]