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Deep neural networks(DNNs) for time series classification have potential security concerns due to their vulnerability to adversarial attacks.The existing attack methods on time series performglobal perturbation based on gradient information,and the generated adversarial examples are easy to be perceived.This paper proposes a locally black-box method to attack DNNs without gradient information.First,the attack is described as a constrained optimization problem with the assumption that the method cannot get any inner information of the model,then the genetic algorithm is employed to solve it.Second,since time series shapelets provides the most discriminative information among different categories,it is designed as a local perturbation interval.Experimental results on UCR datasets that have potential security concerns indicate that the proposed method can effectively attack DNNs and generate adversarial samples.In addition,compared with the benchmark,the method significantly reduces the mean squared error while keeping a high success rate.

Soil moisture and nitrogen nutrient are the two principal factors affecting rice production. Alternating dry and wet irrigation (AWD) coupled with nitrogen application plays important roles in root growth and yield formation in rice. However, its effect on grain filling physiology and their relationship with root physiology is not clearly understood. To explore the effects of alternating dry and wet irrigation and nitrogen application coupling on grain filling, changes of key enzyme activities involved in sucrose-to starch conversion and hormone contents, and root physiology of rice, the super rice variety Nanjing 9108 was cultivated as the material in the field. The field experiments were conducted with two irrigation regimes [conventional irrigation (CI) and AWD] and five nitrogen application rates [no nitrogen fertilizer (0N), 90 kg hm-2 (90N), 180 kg hm-2 (180N), 270 kg hm-2 (270N), and 360 kg hm-2 (360N) nitrogen fertilizer]. The results showed that there was a significant interaction effect between irrigation method and nitrogen application rate. Alternating dry and wet irrigation increased the maximum grain filling rate and average grain filling rate of Nanjing 9108, and increased the activities of the sucrose synthase enzymes, adenosine diphosphate glucose pyrophosphorylation enzymes, starch synthase enzymes, and starch branching enzymes, and the contents of zeatin + zeatin riboside, 3-indoleacetic acid and abscisic acid, increased root oxidation activity, and the content of zeatin + zeatin riboside in roots after heading, promoted the transfer of NSC stored in the stem sheath to the grain in the early growth stage of rice, and the highest yield was obtained after coupling with 270N, which was the best water-nitrogen coupling mode in this experiment. In conclusion, the water-nitrogen coupling effect can be exerted by appropriate regulation of water and fertilizer, which can improve the physiological performance of rice roots and grain-filling physiological activity, and achieve high rice yield. [ABSTRACT FROM AUTHOR]

Background and Purpose: Gut microbiota dysbiosis induced by acute pancreatitis (AP) exacerbates pancreatic injury and systemic inflammatory responses. The alleviation of gut microbiota dysbiosis through faecal microbiota transplantation (FMT) is considered a potential strategy to reduce tissue damage and inflammation in many clinical disorders. Here, we aim to investigate the effect of gut microbiota and microbiota‐derived metabolites on AP and further clarify the mechanisms associated with pancreatic damage and inflammation. Experimental Approach: AP rat and mouse models were established by administration of caerulein or sodium taurocholate in vivo. Pancreatic acinar cells were exposed to caerulein and lipopolysaccharide in vitro to simulate AP. Key Results: Normobiotic FMT alleviated AP‐induced gut microbiota dysbiosis and ameliorated the severity of AP, including mitochondrial dysfunction, oxidative damage and inflammation. Normobiotic FMT induced higher levels of NAD+ (nicotinamide adenine dinucleotide)‐associated metabolites, particularly nicotinamide mononucleotide (NMN). NMN administration mitigated AP‐mediated mitochondrial dysfunction, oxidative damage and inflammation by increasing pancreatic NAD+ levels. Similarly, overexpression of the NAD+‐dependent mitochondrial deacetylase sirtuin 3 (SIRT3) alleviated the severity of AP. Furthermore, SIRT3 deacetylated peroxiredoxin 5 (PRDX5) and enhanced PRDX5 protein expression, thereby promoting its antioxidant and anti‐inflammatory activities in AP. Importantly, normobiotic FMT‐mediated NMN metabolism induced SIRT3–PRDX5 pathway activation during AP. Conclusion and Implications: Gut microbiota‐derived NMN alleviates the severity of AP by activating the SIRT3–PRDX5 pathway. Normobiotic FMT could be served as a potential strategy for AP treatment. [ABSTRACT FROM AUTHOR]