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In this article, a novel fractional‐order recursive integral terminal sliding mode (FORITSM) control is proposed for nonlinear systems in the presence of external disturbances with unknown bounds. The proposed control approach provides an easy‐to implement solution capable of zeroing the sliding variable in a finite‐time (FnT) by adding a fractional‐order command filter. Moreover, the reaching phase is eliminated, and FnT convergence of the system states is proved. The proposed technique has also a chattering alleviation property, which is beneficial for practical cases, as the control of quadrotor UAVs presented in the article. Finally, a simulation case study on a quadrotor system is illustrated to show the effectiveness of the proposed FORITSM control, also with respect to classical methods. [ABSTRACT FROM AUTHOR]

Fenitrothion (FNT), an organophosphorus insecticide, is widely detected in the living environment. The reproductive and endocrine toxicity of FNT to biological communities has been ever reported, but potential mechanism and reproductive toxicity dose effect remain unclear. In our study, we constructed Caenorhabditis elegans model to analyze the reproductive toxicity mechanism of FNT based on metabolomics and evaluated its reproductive toxicity dose effect using benchmark dose (BMD)method. Our results showed that FNT exposure significantly reduced brood size, number of germ cells, and delayed gonadal development in nematodes. Non-targeted metabolomics revealed that FNT exposure caused significant metabolic disturbances in nematodes, leading to a significant reduction in the synthesis of cortisol and melatonin, and the latter played a mediating role in the effects of FNT on number of germ cells. We further found that the levels of these two hormones were significantly negative correlated with the expression of the androgen receptor nhr-69 and affected the meiosis of germ cells by regulating the nhr-69/ fbf-1/2 /gld-3 /fog-1/3 pathway. Meanwhile, the study found the BMDL10s for N2 and him-5 mutant were 0.411 μg/L by number of germ cells and 0.396 μg/L by number of germ cells in the meiotic zone, respectively, providing a more protective reference dose for ecological risk assessment of FNT. This study suggested that FNT can affect androgen receptor expression by inhibiting cortisol and melatonin secretion, which further mediate the meiotic pathway to affect sperm formation and exert reproductive toxicity, and provides a basis for setting reproductive toxicity limits for FNT.

Fenitrothion (FNT), an organophosphorus insecticide, is widely detected in the living environment. The reproductive and endocrine toxicity of FNT to biological communities has been ever reported, but potential mechanism and reproductive toxicity dose effect remain unclear. In our study, we constructed Caenorhabditis elegans model to analyze the reproductive toxicity mechanism of FNT based on metabolomics and evaluated its reproductive toxicity dose effect using benchmark dose (BMD)method. Our results showed that FNT exposure significantly reduced brood size, number of germ cells, and delayed gonadal development in nematodes. Non-targeted metabolomics revealed that FNT exposure caused significant metabolic disturbances in nematodes, leading to a significant reduction in the synthesis of cortisol and melatonin, and the latter played a mediating role in the effects of FNT on number of germ cells. We further found that the levels of these two hormones were significantly negative correlated with the expression of the androgen receptor nhr-69 and affected the meiosis of germ cells by regulating the nhr-69/ fbf-1/2 /gld-3 /fog-1/3 pathway. Meanwhile, the study found the BMDL10s for N2 and him-5 mutant were 0.411 μg/L by number of germ cells and 0.396 μg/L by number of germ cells in the meiotic zone, respectively, providing a more protective reference dose for ecological risk assessment of FNT. This study suggested that FNT can affect androgen receptor expression by inhibiting cortisol and melatonin secretion, which further mediate the meiotic pathway to affect sperm formation and exert reproductive toxicity, and provides a basis for setting reproductive toxicity limits for FNT. • FNT causes reduced nematode fertility, with the most sensitive number of germ cells. • FNT caused a dose-dependent decrease in cortisol and melatonin(MT) in nematodes. • Cortisol and MT played a mediating role in the effect of FNT on number of germ cells. • FNT affected spermatogenesis by regulating nhr-69-mediated germ cell meiosis. • The BMDL10 0.396 ug/L provides a reference dose for ecological benchmark of FNT. [ABSTRACT FROM AUTHOR]