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A field experiment was conducted in the Zhangjiachong watershed to analyze the characteristics of rainfall–runoff process and sediment yield under different types of terraces. Various runoff plots were utilized, and a two serial tank model was employed to simulate runoff generation and concentration processes, taking into account vegetation interception. A soil erosion model incorporating raindrop erosion and sheet erosion was established to replicate sediment yield and concentration process. The parameters of the rainfall–runoff model and soil erosion model were calibrated and validated using observed runoff and sediment yield data. The controlling factors on runoff and sediment yield were explored and compared. The results indicate that both calibration and validation outcomes were acceptable. The earth‐banked terraces–citrus demonstrated the largest coefficients of upper and lower surface runoff, while its upper runoff threshold of the upper tank and the runoff threshold of the lower tank were the lowest, suggesting that it was more likely to produce surface and subsurface runoff. On the other hand, the stone dike terraces–crops exhibited the smallest coefficients of upper and lower surface runoff, while its upper runoff threshold of the upper tank was the highest. The lower runoff threshold of the upper tank was the same across different types of terraces. Compared to the earth‐banked terraces, the stone dike terraces have a larger infiltration coefficient in the upper tank and a smaller infiltration coefficient in the lower tank. Sensitivity analysis indicates that the most sensitive factors affecting runoff simulation results are the runoff threshold and the infiltration coefficient of the lower tank. Terraces, whether constructed with earth banks or stone dikes, are effective in reducing soil erosion. However, during storm rainfall events, these terraces may be partially destroyed, resulting in a higher sediment yield than that of the same vegetation cover on slope land. Terraces with hedgerows have a more significant effect on reducing runoff and sediment than those without hedgerows. [ABSTRACT FROM AUTHOR]

The circadian clock is generated by a molecular timekeeping mechanism coordinating daily oscillations of physiology and behaviors in mammals. In the mammalian circadian clockwork, basic helix–loop–helix ARNT‐like protein 1 (BMAL1) is a core circadian component whose defects lead to circadian disruption and elicit behavioral arrhythmicity. To identify previously unknown regulators for circadian clocks, we searched for genes influencing BMAL1 protein level by using a CRISPR/Cas9‐based genome‐wide knockout library. As a result, we found that the deubiquitinase ubiquitin carboxyl‐terminal hydrolase 1 (USP1) positively affects BMAL1 protein abundance. Overexpression of wild‐type USP1, but not a deubiquitinase‐inactive mutant USP1, upregulated BMAL1 protein level, whereas genetic ablation of USP1 downregulated BMAL1 protein level in U2OS cells. Furthermore, treatment with USP1 inhibitors led to significant downregulation of BMAL1 protein in U2OS cells as well as mouse tissues. Subsequently, genetic ablation or pharmacological inhibition of USP1 resulted in reduced mRNA levels of a panel of clock genes and disrupted circadian rhythms in U2OS cells. Mechanistically, USP1 was able to de‐ubiquitinate BMAL1 and inhibit the proteasomal degradation of BMAL1. Interestingly, the expression of Usp1 was much higher than the other two deubiquitinases of BMAL1 (Usp2 and Usp9X) in the mouse heart, implying a tissue‐specific function of USP1 in the regulation of BMAL1 stability. Our work thus identifies deubiquitinase USP1 as a previously unknown regulator of the mammalian circadian clock and highlights the potential of genome‐wide CRISPR screens in the identification of regulators for the circadian clock. [ABSTRACT FROM AUTHOR]

To efficaciously decrease dielectric loss while still synchronously harvesting a high dielectric constant (ε′) and breakdown strength (Eb), as well as good mechanical properties in silicon (Si)/poly(vinylidene fluoride) (PVDF), in this work, the core@shell structured Si@silicon dioxide (SiO2) particles were first prepared via a high temperature oxidation, and subsequently incorporated into the PVDF to generate morphology‐dependent composites with a high‐ε′ and Eb but low loss. The SiO2 shell effects on the morphology, dielectric, and mechanical properties of PVDF composites were explored. In comparison to pristine Si/PVDF, the Si@SiO2/PVDF presents significantly suppressed loss and boosted Eb because the SiO2 interlayer not only efficiently blocks the connection between the raw Si and greatly impedes the long‐range charges migration even at high filler loadings, but also obviously improves the compatibility between Si and PVDF at the interfaces which promotes fillers' uniform dispersion in host matrix, thus leading to enhanced dielectric and mechanical properties. The fitting result by the Havriliak–Negami equation theoretically elucidates the SiO2 interlayer's suppression effect on charge migration behavior in the composites. More importantly, dielectric properties can be efficiently turned via tailoring the SiO2 shell thickness. The Si@SiO2/PVDF with simultaneously enhanced dielectric and mechanical performances shows promising uses in the electrical and microelectronics industries. [ABSTRACT FROM AUTHOR]

As the electronic industry develops rapidly, nowadays, flexible dielectric materials with excellent integrated dielectric performances including high dielectric permittivity (ɛ) and breakdown strength (Eb) but low loss, are highly pursued. In this work, to concurrently improve the ɛ and Eb but restrain the loss of original Si/polyvinylidene fluoride (PVDF) composites, the core@shell structured Si@SiO2 particles first were produced via high temperature oxidation process, and then incorporated into the PVDF to generate morphology-dependent composites with high-ɛ and Eb but low loss. The dielectric properties of the composites were investigated in terms of the filler types and concentrations, frequency, and theoretically fitted using the Havriliak-Negami equation to reveal the SiO2 shell' role in affecting the polarization mechanism. When compared to pure Si/PVDF at high filler loadings, remarkably inhibited dielectric loss and conductivity as well as enhanced Eb concurrently can be achieved in the Si@SiO2/PVDF composites still harvesting a high-ɛ. This is because the insulating SiO2 shell not only effectively prevents the raw Si particles from direct physical contact, but also greatly impedes the long-range charge carrier migration via raising energy barrier subsequently leading to obviously enhanced Eb. Moreover, the dielectric loss and conductivity apparently decrease with increasing the SiO2 shell thickness due to its pronounced suppression effect. The prepared Si@SiO2/PVDF with a high Eb and ɛ but low loss, show bright future uses in micro-electronic devices used for high-voltage purposes. [ABSTRACT FROM AUTHOR]