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This paper studies the active fault tolerant load frequency control of multi‐area power systems with electric vehicles under deception attacks. An integrated design of fault estimation and fault‐tolerant control is proposed to guarantee the stability of the system under sensor faults and deception attacks. Considering the uncertainty caused by the demand of the owner and the state of the battery, a multi‐area power system model is proposed. Then, an active fault tolerant load frequency control scheme is designed. The proportional‐derivative sliding mode observer is used to estimate the fault and system status in real‐time. During the fault occurrence, the estimated value obtained by the observer is utilized to design the controller without any fault diagnosis scheme, which simplifies the controller design process. A sufficient Lyapunov‐Krasovskii criterion is derived to ensure the stability performance of the multi‐area power system. Finally, simulation examples are provided for a three‐area power system contains electric vehicles, and the results prove the correctness and feasibility of the proposed fault‐tolerant control scheme. [ABSTRACT FROM AUTHOR]

The performance limitation of networked control systems (NCSs) with networked delay and two-channel noises constraints are studied in this paper. The networked parameters mainly consider the networked delay in the forward channel and white Gaussian noise constraint existing in forward channel and feedback channel. The tracking performance limitation expression is achieved by using the spectral decomposition technique and selecting the optimal one-parameter structure. The obtained result shows that the tracking performance limitation of NCSs is related to the position of the non-minimum phase zeroes, the position of the unstable poles, networked delay, two-channel noises and input signal. We can also know that the networked delay and white Gaussian noise have influence on the tracking performance limitation of NCSs. Finally, a simulation example is given to demonstrate effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

The contents of 57 ginsenosides were measured in American ginseng roots collected from a single population grown in Jilin. Ginsenoside contents and compositions varied significantly among the population. The most abundant ginsenoside within the American ginseng root and by population was either Rg 1 or Re, followed by Rb 1 , mal-Rb 1 , Rd, Rc, pseudoginsenoside F 11 , Ro, and gypenoside XVII. According to the relative contents of Rg 1 and Re, the population was grouped into two chemotypes, and there were significant differences in ginsenoside profiles between them. The contents of protopanaxadiol-type ginsenosides were relatively stable. The rate-limiting enzymes of malonyl ginsenosides biosynthesis were located in front of their corresponding neutral ginsenosides. The regulatory sites of the oleanolic acid-type ginsenosides biosynthetic pathway were in front of the β -amyrin.

Euphorbia lathyris L. is a biennial herb in the Euphorbiaceae that has been used as a medicinal plant. It is distributed or cultivated worldwide, and the seeds of E. lathyris are the main source of ingenol, which is the precursor of Picato, the first medicine approved by USFDA for the treatment of solar keratosis (Abramovits et al. 2013). However, the production of E. lathyris can be severely hampered by the occurrence of plant diseases. Between 2020-2022 (specifically in October-November of each year), anthracnose-like symptoms were observed on E. lathyris in fields (E 118°49'50″, N 32°3'33″) in Nanjing, Jiangsu Province, China. The incidence of E. lathyris with disease symptoms was between 25%-30% (n = 100). The lesions on the leaves were evident initially as dark brown spots, which expanded into larger necrotic spots, finally resulting in leaves withering and dropping off. In severe cases, stem wilting was also observed. To determine the causal agent, we collected diseased leaf samples (n = 20) from different E. lathyris plants in the field (~ 1800 m2). After cleaning, the junctions of the diseased and healthy parts were excised and sterilized in 75% ethanol for 20-25 seconds, and rinsed with sterile water. After that, they were transferred onto potato sucrose agar (PSA) plates and placed at 25℃ for 3-4 days, until fungal growth was evident. The fungus was purified by recovering single conidia and growing them on PSA (Hu et al. 2015). A consistent fungal colony, based on morphological characteristics, was recovered from 17 samples. The colony color was initially white, green in the middle, and gradually changed into gray green as the colony matured. Conidia were transparent and cylindrical (22-28 µm × 7-9 µm, n = 50). Five loci informative (ITS, TUB, ACT, GAPDH, and CHS-1) (Weir et al. 2012) for Colletotrichum spp. identification were sequenced from two isolates ELC-1 and ELC-2 obtained from different plant individuals. Compared with a reference isolate (Colletotrichum gloeosporioides ZH3), the GAPDH, CHS-1, and TUB2 sequences of ELC-1 and ELC-2 showed 95% (263 bp out of 275 bp), 98% (295 bp out of 299 bp), and 99% (711 bp out of 712 bp and 717 bp out of 719 bp) similarity, respectively. The ITS sequence identities were 100% (577 bp out of 577 bp) and 99% (594 bp out of 597 bp), while the ACT sequence identities were 100% (281 bp out of 281 bp) and 98% (279 bp out of 284 bp). All sequences have been deposited in Genbank database (OR865865-OR865866 and OR873625-OR873632). After performing phylogenetic analysis with Mega 11, the pathogen was confirmed as C. gloeosporioides. To fulfil Koch's postulates, we sprayed six-week-old healthy plants with a conidia suspension of C. gloeosporioides (106 spores/mL) or sterile water (serve as control). The inoculated plants were placed at 25℃, 100% relative humidity, and 12-h photoperiod (Zhang et al. 2021). Six plants were inoculated for each treatment, and the experiment was repeated three times. After 6-8 days, the plants inoculated with C. gloeosporioides showed similar symptoms to those observed on diseased plants in the field, while the control plants remained healthy and free of disease. The pathogens were then re-isolated and identified as C. gloeosporioides. To our knowledge, this is the first report of C. gloeosporioides causing anthracnose on E. lathyris. Anthracnose may cause significant yield losses in E. lathyris production, and our results will provide experimental and theoretical basis for the management of the disease.