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The toxic heavy metal antimony (Sb) is ubiquitous in our daily lives. Various models have shown that Sb induces neuronal and reproductive toxicity. However, little is known about the developmental toxicity of Sb exposure during gestation and the underlying mechanisms. To study its effects on growth and development, Drosophila stages from eggs to pupae were exposed to different Sb concentrations (0, 0.3, 0.6 and 1.2 mg/mL Sb); RNA sequencing was used to identify the underlying mechanism. The model revealed that prenatal Sb exposure significantly reduced larval body size and weight, the pupation and eclosion rates, and the number of flies at all stages. With 1.2 mg/mL Sb exposure in 3rd instar larvae, 484 genes were upregulated and 694 downregulated compared to controls. Biological analysis showed that the disrupted transcripts were related to the oxidative stress pathway, as verified by reactive oxygen species (ROS) scavenger N -acetylcysteine (NAC) and glutathione (GSH) intervention experiments. Sb exposure induced oxidative stress imbalance could be rectified by chelation and antioxidant effects of NAC/GSH. The Drosophila Schneider 2 (S2) model further demonstrated that NAC and GSH greatly ameliorated cell death induced by Sb exposure. In conclusion, gestational Sb exposure disrupted oxidative stress homeostasis, thereby impairing growth and development. [Display omitted] • A Drosophila model of gestational Sb exposure was performed to investigate effects on development. • Sb exposure reduced larval body size, larval weight, pupation and eclosion rates. • Sb exposure induced genotoxicity related with oxidative stress pathway. • Sb mediated oxidative stress imbalance was rectified by chelation and antioxidant effects of NAC/GSH. [ABSTRACT FROM AUTHOR]

Triggering economic growth is a requirement to promote human welfare and realize sustainable development in many developing countries. However, place-based policies' impact on economic growth is debatable, and its underlying mechanism is unknown. China's Old Revolutionary Development Program (ORDP) is a large-scale and novel type of place-based policy targeted at undeveloped regions in China. We evaluate the effect of ORDP on economic growth by employing a time-varying difference-in-differences model and further explore the potential mechanisms and heterogeneity effects. VIIRS/DNB nightlight data is used to measure economic growth. We find that ORDP can significantly promote economic growth by 4.0% and the result is still robust after several tests. Mechanism analysis shows that ORDP can improve economic growth through government intervention, industrial structure optimization, and information infrastructure construction. Heterogeneity analysis indicates that the ORDP performs better on economic growth in central Chinese cities and high-economy cities. At the same time, our paper provides three practical suggestions for stimulating economic growth in ORDP, which can be enlightening for other developing countries. [ABSTRACT FROM AUTHOR]

Aiming at the problem of quantifying the composition of complex fracture network and fracture activation after fracturing, a complex fracture network model of weak plane with prefabricated structure is established based on finite element method, global embedded cohesive zone model (CZM), and real shale outcrop. Considering the influence of fully coupled stress/fluid, the effects of weak plane azimuth, horizontal stress difference, fracturing fluid viscosity, and injection rate on fracture network composition, geometry, and stimulated reservoir volume (SRV) are studied. The concept of fracture relative activation rate, which can quantitatively analyze fracture network composition and fracture activation, is proposed. The results show that the fracture geometry of the two kinds of conjugated shale after fracturing is controlled by the most weak mechanical plane, and the fracture network is, respectively, axisymmetric and centrosymmetric. The fracture network is composed of the weak plane fractures with the dominant free gas transport and the matrix microfractures with the dominant adsorbed gas transport. The effects of weak plane azimuth, horizontal stress difference, and fracturing fluid viscosity on SRV length are not monotonous, while the increase of the azimuth, horizontal stress difference, fracturing fluid viscosity, and the reduction of appropriate injection rate will lead to the increase of SRV width. The effect of horizontal stress difference on the relative activation rate of fractures does not change monotonically, while the increase of weak plane azimuth, fracturing fluid viscosity, and injection rate will lead to the increase of the relative activation rate of matrix microfractures, the increase of the total length of activated fractures, and the decrease of the relative activation rate of weak plane fractures. [ABSTRACT FROM AUTHOR]

Temporary plugging technology is widely used in the volume fracturing of horizontal wells. However, conventional temporary plugging balls and particles can't effectively plug perforations during fracturing. This research designed a completely degradable, tassel-shaped rope knot temporary plugging agent, and it has an excellent degradation and plugging performance. The knot temporary plugging agent's solubility, crushing rate, temperature and shear resistance were evaluated. The knot temporary plugging agent can completely degrade into CO2 and water in a clean water environment. According to the physical model of the transparent tube, the knot temporary plugging agent can quickly enter the perforation with the help of the tassel-shaped wings to form an effective plugging. Compared with the conventional temporary plugging ball, the ability to enter the perforation and the plugging performance were superior. The field application of the knot temporary plugging agent in MaHW#5 well showed that the temporary plugging effect was good. [ABSTRACT FROM AUTHOR]

A new type of student information management system is designed to implement student information identification and management based on fingerprint identification. In order to ensure the security of data transmission, this paper proposes a data encryption method based on an improved AES algorithm. A new S-box is cleverly designed, which can significantly reduce the encryption time by improving ByteSub, ShiftRow, and MixColumn in the round transformation of the traditional AES algorithm with the process of look-up table. Experimental results show that the proposed algorithm can significantly improve the encryption time compared with the traditional AES algorithm. [ABSTRACT FROM AUTHOR]