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Creators/Authors contains: "Liu, Sen"

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  1. With the rapid development of deep reinforcement learning technology, it gradually demonstrates excellent potential and is becoming the most promising solution in the robotics. However, in the smart manufacturing domain, there is still not too much research involved in dynamic adaptive control mechanisms optimizing complex processes. This research advances the integration of Soft Actor-Critic (SAC) with digital twins for industrial robotics applications, providing a framework for enhanced adaptive real-time control for smart additive manufacturing processing. The system architecture combines Unity’s simulation environment with ROS2 for seamless digital twin synchronization, while leveraging transfer learning to efficiently adapt trained models across tasks. We demonstrate our methodology using a Viper X300s robot arm with the proposed hierarchical reward structure to address the common reinforcement learning challenges in two distinct control scenarios. The results show rapid policy convergence and robust task execution in both simulated and physical environments demonstrating the effectiveness of our approach. 
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    Free, publicly-accessible full text available May 29, 2026
  2. Little is known concerning terpenoids produced by members of the fungal order Ophiostomales, with the member Harringtonia lauricola having the unique lifestyle of being a beetle symbiont but potentially devastating tree pathogen. Nine known terpenoids, including six labdane diterpenoids (1–6) and three hopane triterpenes (7–9), were isolated from H. lauricola ethyl acetate (EtOAc) extracts for the first time. All compounds were tested for various in vitro bioactivities. Six compounds, 2, 4, 5, 6, 7, and 9, are described functionally. Compounds 2, 4, 5, and 9 expressed potent antiproliferative activity against the MCF-7, HepG2 and A549 cancer cell lines, with half-maximal inhibitory concentrations (IC50s) ~12.54–26.06 μM. Antimicrobial activity bioassays revealed that compounds 4, 5, and 9 exhibited substantial effects against Gram-negative bacteria (Escherichia coli and Ralstonia solanacearum) with minimum inhibitory concentration (MIC) values between 3.13 and 12.50 μg/mL. Little activity was seen towards Gram-positive bacteria for any of the compounds, whereas compounds 2, 4, 7, and 9 expressed antifungal activities (Fusarium oxysporum) with MIC values ranging from 6.25 to 25.00 μg/mL. Compounds 4, 5, and 9 also displayed free radical scavenging abilities towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide (O2−), with IC50 values of compounds 2, 4, and 6 ~3.45–14.04 μg/mL and 22.87–53.31 μg/mL towards DPPH and O2−, respectively. These data provide an insight into the biopharmaceutical potential of terpenoids from this group of fungal insect symbionts and plant pathogens. 
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  3. null (Ed.)
  4. Summary White‐nose syndrome, a disease that is caused by the psychrophilic fungusPseudogymnoascus destructans, has threatened several North America bat species with extinction. Recent studies have shown that East Asian bats are infected withP. destructansbut show greatly reduced infections. While several factors have been found to contribute to these reduced infections, the role of specific microbes in limitingP. destructansgrowth remains unexplored. We isolated three bacterial strains with the ability to inhibitP. destructans, namely,Pseudomonas yamanorumGZD14026,Pseudomonas brenneriXRD11711 andPseudomonas fragiGZD14479, from bats in China.Pseudomonas yamanorum, with the highest inhibition score, was selected to extract antifungal active substance. Combining mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy analyses, we identified the active compound inhibitingP. destructansas phenazine‐1‐carboxylic acid (PCA), and the minimal inhibitory concentration (MIC) was 50.12 μg ml−1. Whole genome sequencing also revealed the existence of PCA biosynthesis gene clusters. Gas chromatography‐mass spectrometry (GC‐MS) analysis identified volatile organic compounds. The results indicated that 10 ppm octanoic acid, 100 ppm 3‐tert‐butyl‐4‐hydroxyanisole (isoprenol) and 100 ppm 3‐methyl‐3‐buten‐1‐ol (BHA) inhibited the growth ofP. destructans. These results support that bacteria may play a role in limiting the growth ofP. destructanson bats. 
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