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With the increasing penetration of distributed generators (DGs) and the growing demand for reliable power sources, it has become imperative to promptly identify anomalies in active distribution networks (ADNs). Additionally, anomaly identification is also crucial to assisting in targeting maintenance to handle failures after the action of relay protections. This study presents a highly accurate and rapidly responsive approach to identifying anomalies in ADNs. The proposed method uses three layers of intricately interconnected modules. In the first module, an iterative clustering layer is devised to process the original data. In the second module, an association rule layer is designed to identify hidden patterns based on the types of anomalies and the post-fault voltage. In the third module, a regression training layer is employed to train accurate identification models. The case study utilizes data samples collected by an IEEE 33-bus system with distributed generations as well as post-fault data from a practical distribution network. The results of comparative tests demonstrate that the proposed data-mining structure achieves reliable performance with high identification accuracy and short reaction times, indicating its ability to be applied to the state awareness system of ADNs.

Nineteen new talaroenamine derivatives, talaroenamines F1–F19 (1–19), were isolated from the Yellow River wetland derived Penicillium malacosphaerulumHPU-J01 by use of a one-pot/two-stage precursor-directed biosynthesis approach. During this approach, the initial precursor p-methylaniline was first used as a carrier to capture the biologically synthesized cyclohexanedione to produce talaroenamine F, and then the other aniline derivatives were employed to replace the p-methylaniline fragment of talaroenamine F to generate the final products. LC–MS analysis showed that only four compounds (2, 8, 10, and 12) could be produced by the traditional precursor-directed biosynthesis in which the aniline precursors were added simultaneously. Compound 14was cytotoxic against the K562 cell line with an IC50value of 2.2 μM. This work demonstrated the one-pot/two-stage precursor-directed biosynthesis could improve substrate acceptance leading to the production of diverse talaroenamines.

Four new polyketides, penitalarins A–C (1–3) and nafuredin B (4), together with the known biogenetically related nafuredin A (5) were isolated from a mixed culture of a deep-sea-derived fungus Talaromyces aculeatusand a mangrove-derived fungus Penicillium variabile. Liquid chromatography/mass spectrometry analysis showed that none of compounds 1–5was produced by either of the two fungi when cultured alone under the same condition. The structures of 1–4, including absolute configurations, were deduced based on the interpretation of MS, NMR data, and time-dependent density functional theory calculations of specific electronic circular dichroism spectra. Compounds 1–3possess a 3,6-dioxabicyclo[3.1.0]hexane ring, and 4showed cytotoxicity with IC50values ranging from 1.2 to 9.8 μM against a panel of human cancer cell lines.

Four new tetramic acids, cladosins H–K (1–4), and a related known compound, cladodionen (5), were isolated from the culture of the Mariana Trench (depth 6562 m) sediment-derived fungus Cladosporium sphaerospermumL3P3 treated with the histone deacetylase inhibitor SAHA (suberanilohydroxamic acid). Interestingly, compounds 1–5existed as equilibrium E/Zmixtures and 1–4were the first cases of tetramic acids containing aniline moieties. Their structures including absolute configurations were elucidated through a combination of NMR, MS, and Mosher’s method, together with the consideration of biogenetic origins. Incubation experiments of exogenous aniline and N-phenyloctanamide revealed that the aniline moiety in cladosins H–K (1–4) is probably derived from the degradation of SAHA, indicating that the well-known histone deacetylase inhibitor SAHA could be metabolized by L3P3 and provide aniline as a precursor for biotransformation of chemically reactive polyketides. The cytotoxicity of 1–5was evaluated against the PC-3, MGC-803, SH-SY5Y, HCT-116, K562, and HL-60 cell lines, and compound 2showed promising cytotoxicity against the HL-60 cell line with an IC50value of 2.8 μM.

A new, highly modified fatty acid amide, varitatin A (1), was isolated from the fungus Penicillium variabileHXQ-H-1 cultivated with the DNA methyltransferase inhibitor 5-azacytidine. The structure including the absolute configuration of 1was established by analysis of NMR and MS data, together with chemical degradation and Mosher’s method based on MPA esters. Compound 1showed cytotoxicity against HCT-116 cells with an IC50value of 2.8 μM and also inhibited the effects of protein tyrosine kinases.