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To mitigate the impact of low-frequency noise from the tunnel magnetoresistance (TMR) current sensor and ambient stray magnetic fields on weak current detection accuracy, we propose a high-resolution modulation-demodulation test method. This method modulates and demodulates the measurement signal, shifting low-frequency noise to the high-frequency band for effective filtering, thereby isolating the target signal from the noise. In this study, we developed a Simulink model for the TMR current sensor modulation-demodulation test method. Practical time-domain and frequency-domain tests of the developed high-resolution modulation-demodulation method revealed that the TMR current sensor exhibits a nonlinearity as low as 0.045%, an enhanced signal-to-noise ratio (SNR) of 77 dB, and a heightened resolution of 100 nA. The findings indicate that this modulation-demodulation test method effectively reduces the impact of low-frequency noise on TMR current sensors and can be extended to other types of resistive devices. [ABSTRACT FROM AUTHOR]

To explore the degree of constraint by Global Navigation Satellite System (GNSS) and Interferometric Synthetic Aperture Radar (InSAR) data on the Maduo earthquake within a layered earth model structure and to gain an insight into the seismogenic mechanism and the seismic risk in the surrounding area, this study employs D-InSAR technology to acquire the InSAR co-seismic deformation field of the Maduo earthquake on 22 May 2021. Utilizing both GNSS and InSAR data, the inversions constrained by single and joint data are conducted and compared to determine the co-seismic slip model and fault plane stress distribution of the Maduo earthquake. Additionally, this paper calculates the Coulomb stress changes induced by 14 M ≥ 7 strong earthquakes, considering co-seismic effects, post-seismic viscoelastic relaxation, and inter-seismic tectonic stress loading, on 19 fault segments within the Bayan Har block research area (96°E~106°E, 29°N~36°N) since 1900. The findings are as follows: (1) The maximum line-of-sight (LOS) deformation was approximately 0.9 m. The joint inversion rupture was primarily located in the Dongcao Along Lake section (~98.6°E), aligning with previous research outcomes. (2) The cumulative Coulomb stress at the Maduo earthquake's source location was −0.1333 MPa, while the inter-seismic stress loading amounted to 0.0745 MPa. The East Kunlun Fault, Maduo–Gande Fault, Ganzi–Yushu Fault, and Dari Fault C exhibited considerable stress loading, warranting attention due to heightened seismic risk. (3) Based on three different co-seismic slip models, the stress disturbance results caused by the Maduo earthquake to the surrounding area and fault did not differ significantly. After the earthquake, the seismogenic fault still has high seismic risk. [ABSTRACT FROM AUTHOR]

Recombinases are in part responsible for homologous recombination and genome integrity during DNA repair. DMC1 has a typical RecA domain, and belongs to the recombinase superfamily. The reactive oxygen species (ROS) as a potent DNA damage agent is produced during seed germination under stress conditions. DNA repair should be initiated immediately to allow for subsequent seedling development. In this study, we attempted to characterize the underlying mechanism of BrDMC1 responsiveness to salinity stress using the RNA interference approach in Brassica rapa (B. rapa). Bioinformatics and expression pattern analysis revealed that BrDMC1 only retained BrDMC1.A01 after the whole genome triplication (WGT) event and was primarily transcribed in flowers and seeds. BrDMC1 had high activity in the promoter region during germination, according to histochemical GUS staining. The data showed that salt treatment reduced the germination rate, weakened seed vigor and decreased antioxidant enzyme activity, but increased oxidative damage in BrDMC1-RNAi seeds. Furthermore, the expression of stress-responsive genes and damage repair genes was significantly different in transgenic lines exposed to salt stress. Therefore, BrDMC1 may respond to salt stress by controlling seed germination and the expression of stress-related and damage repair genes in B. rapa. [ABSTRACT FROM AUTHOR]

The design and preparation of hydrophobic, wear-resistant, and thermally conductive multifunctional composites is an important direction of scientific research and application. In this study, A-CF/EP/FEP composites were prepared by incorporating APDMS-modified carbon felt (A-CF) into an epoxy resin (EP) and fluorinated ethylene propylene resin (FEP) mixed resin. The low surface energy of FEP, good adhesion of EP, and the supporting of carbon felt framework endow the A-CF/EP/FEP composites with hydrophobicity, wear resistance, and thermal conductivity at the same time. Firstly, the water contact angle (WCA) of A-CF/EP/FEP composites with 20 wt% FEP reaches 109.9 ± 2.6°, and the WCAs of all composites with different FEP contents (10, 20, 30, 40, and 50 wt%) is greater than 90°, indicating the composites have a hydrophobic surface. Secondly, the A-CF/EP/FEP composites have high wear resistance and maintain long-term hydrophobicity after tribological tests, because the residual debris and nanoparticles generated by external loading adhere to the friction interface, regenerating the microstructure of the hydrophobic surface. Finally, the A-CF/EP/FEP composites have high thermal conductivity up to 0.38 W/(m·K), which is 1.81 and 2.0 times that of pure EP and EP/FEP composites, respectively. This is because a relatively complete heat conduction network is formed after the addition of A-CF to the composites. The synergy among epoxy resin, FEP, and the A-CF filler plays a particularly important role in constructing hydrophobic surfaces and improving wear resistance and thermal conductivity. The EP enhances adhesion, the FEP supplies low surface energy, and the A-CF framework improves the wear resistance of A-CF/EP/FEP composites. This work provides ideas for the design and preparation of multifunctional composites and will underlie the application of high-performance epoxy resin and its composites. [ABSTRACT FROM AUTHOR]