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The initial loss of tension in individual bolts after initial tightening obviously affects the level and the stability of the clamp load in bolted joints. A high-precision instrument to analyze the clamp load loss was developed. In this instrument, an Atlas Copco’s high performance spindle with an accuracy of ±2.5% under the conditions of one million duty cycles was used to tighten the test bolts and nuts. A rotary torque-angle transducer was integrated in the tightening spindle to measure the tightening torque. KMR force washer with a repeatability of < ±1% was applied to monitor the clamping force in real time. Using this instrument, the design of experiment analysis was performed to determine the effect of variables on the initial loss of tension. Those variables included the joint materials, the fastener class, the gasket grade, the lubrication, the surface roughness, the tightening speed, and the number of repeated tightening. The results showed that the tightening speed and the number of repeated tightening had a significant effect on the initial loss of tension. Moreover, a process criterion of eliminating plastic deformation was proposed to minimize the initial loss of tension. The findings presented in this paper will be expected to enhance the reliability and the safety of bolted assemblies, especially in critical applications. [ABSTRACT FROM AUTHOR]

Objective: Triple-negative breast cancer (TNBC) is a subtype with high invasiveness. Due to lacking specific and effective therapies, it is necessary to explore the mechanism of TNBC progression and search for new therapeutic targets., Methods: Data from the GEPIA2 database was analyzed to explore RNF43 expression in each subtype of breast cancer. RNF43 expression in TNBC tissue and cell lines was determined by RT-qPCR. In vitro biological function analyses including MTT assay, colony formation assay, wound-healing assay and Transwell assay were conducted to explore the role of RNF43 in TNBC. In addition, the markers of epithelial-mesenchymal transition (EMT) were detected by western blot. The expression of β-Catenin and its downstream effectors were also detected., Results: Data from the GEPIA2 database indicated that RNF43 expression was lower in tumor tissue compared to paired adjacent tissue in TNBC. In addition, RNF43 expression in TNBC was lower than in other subtypes of breast cancer. Consistently, down-regulation of RNF43 expression in TNBC tissue and cell lines was observed. Overexpressing RNF43 attenuated the proliferation and migration of TNBC cells. Depletion of RNF43 showed the opposite effect, confirming that RNF43 played an anti-oncogenic role in TNBC. In addition, RNF43 suppressed several markers of EMT. Furthermore, RNF43 restrained the expression of β-Catenin and its downstream effectors, implying RNF43 exerted the suppressive role in TNBC by inhibiting the β-Catenin pathway., Conclusions: This study demonstrated that the RNF43-β-Catenin axis attenuated TNBC progression, which might provide novel therapeutic targets for TNBC., (© 2023 by the Association of Clinical Scientists, Inc.)

Objective: To explore the correlation of the position and height of the examination couch with the accuracy of image registration in an exact effective field of vision (FOV) of single photon emission computed tomography/computed tomography (SPECT/CT) and determine the optimal position of the examination couch for best image registration., Methods: The tests were performed on a SPECT/CT with 6 radioactive (153)Gd sources in 3 groups (two in each group with energy peak of 40.9 Kev, 41.54 Kev, and 103.18 Kev) in an assorted standard pattern. Thirteen groups of slice data were obtained by changing the position and height of the bed but keeping the tomograpy slice constant. The bias of the accuracy of image registration was acquired using ALIGNMENT software and compared for different examination couch positions and heights., Results: The position of the examination couch at 0 cm in the Z axis and -4 cm in the Y axis showed the least error of image registration., Conclusion: To achieve optimal SPECT and CT image fusion, quality control must be implemented and calibration of image registration accuracy should be done when necessary.