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Design,synthesis,and biological evaluation of benzo[4,5]thieno[2,3-d]pyrimidine derivatives as novel HIV-1 NNRTIs

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Chinese Chemical Letters 2024年第6期35卷 344-348页

作者： Bairu meng Zongji Zhuo Han yu Sining Tao Zixuan Chen Erik De Clercq Christophe Pannecouque Dongwei kang Peng Zhan Xinyong Liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJi’nan 250012China Laboratory of Virology and Chemotherapy Rega Institute for Medical ResearchK.U.LeuvenLeuven B-3000Belgium China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province Ji’nan 250012China

Inspired by our previous studies to discover novel human immunodeficiency virus-1(HIV-1)nonnucleoside reverse transcriptase inhibitors(NNRTIs)by targeting the tolerant region II of the NNRTIs binding pocket(NNIBP),a series of novel benzo[4,5]thieno[2,3-d]pyrimidine derivatives were designed through structure-based drug design as novel potent HIV-1 *** results showed that compound16b was the most active inhibitor,exhibiting 50% effective concentration(EC50)values from 0.021μmol/L to 0.298μmol/L against wild-type(WT)and a panel of NNRTIs-resistant HIV-1 ***,16b was demonstrated with a significantly low 50% cytotoxicity concentration(CC_(50))value(>200μmol/L)and high selectivity index(SI)*** addition,16b yielded moderate reverse transcriptase(RT)enzyme inhibition with a 50% inhibition concentration(IC_(50))value of 0.183μmol/L,which demonstrated that it acted as HIV-1 *** binding mode of 16b with RT was also illustrated via molecular ***,this work provided a novel lead compound for developing potent HIV-1 NNRTIs.

关键词： HIV-1 NNRTIs DAPYs Tolerant regionⅡ Drug design

Physics-informed deep Koopman operator for Lagrangian dynamic systems

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Science China(Information Sciences) 2024年第9期67卷 146-163页

作者： Xuefeng WANG Yang CAO Shaofeng CHEN yu kang Department of Automation University of Science and Technology of China State Key Laboratory of Fire Science University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China

Accurate mechanical system models are crucial for safe and stable control. Unlike linear systems,Lagrangian systems are highly nonlinear and difficult to optimize because of their unknown system *** research thus used deep neural networks to generate linear models of original systems by mapping nonlinear dynamic systems into a linear space with a Koopman observable function encoder. The controller then relies on the Koopman linear model. However, without physical information constraints, ensuring control consistency between the original nonlinear system and the Koopman system is tough, as the learning process of the Koopman observation function is unsupervised. This paper thus proposes a two-stage learning algorithm that uses structural subnetworks to build a physics-informed network topology to simultaneously learn the Koopman observable functions and the system energy representation. In the Koopman matrix learning session, a quadratic-constrained optimization problem is solved to ensure that the Koopman representation satisfies the energy difference matching hard constraint. The proposed energy-preserving deep Lagrangian Koopman(EPDLK) framework effectively represents the dynamics of the Lagrangian system while ensuring control consistency. The effectiveness of EPDLK is compared with those of various Koopman observable function construction methods in multistep prediction and trajectory tracking tasks. EPDLK achieves better control consistency by guaranteeing energy difference matching, which facilitates the application of the control law generated on the Koopman system directly to the original nonlinear Lagrangian system.

关键词： Koopman operator Lagrangian physics-informed nonlinear model predictive control (MPC)

Autonomous multi-drone racing method based on deep reinforcement learning

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Science China(Information Sciences) 2024年第8期67卷 35-48页

作者： yu kang Jian DI Ming LI yunbo ZHAO yuhui WANG Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Racing drones have attracted increasing attention due to their remarkable high speed and excellent maneuverability. However, autonomous multi-drone racing is quite difficult since it requires quick and agile flight in intricate surroundings and rich drone interaction. To address these issues, we propose a novel autonomous multi-drone racing method based on deep reinforcement learning. A new set of reward functions is proposed to make racing drones learn the racing skills of human experts. Unlike previous methods that required global information about tracks and track boundary constraints, the proposed method requires only limited localized track information within the range of its own onboard sensors. Further, the dynamic response characteristics of racing drones are incorporated into the training environment, so that the proposed method is more in line with the requirements of real drone racing scenarios. In addition, our method has a low computational cost and can meet the requirements of real-time racing. Finally, the effectiveness and superiority of the proposed method are verified by extensive comparison with the state-of-the-art methods in a series of simulations and real-world experiments.

关键词： racing drone autonomous multi-drone racing sim-to-real deep reinforcement learning Markov game

Fracture behavior and mechanism of highly fragmented steel cylindrical shell under explosive loading

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Defence Technology（防务技术） 2024年第6期36卷 122-132页

作者： kang Wang Peng Chen Xingyun Sun yufeng Liu Jiayu meng Xiaoyuan Li Xiongwei Zheng Chuan Xiao Xi'an Modern Chemistry Research Institute Xi'an 710065China Shanxi Jiangyang Chemical Company Limited Taiyuan 030051China Central Iron&Steel Research Institute Company Limited Beijing 100081China China Research and Development Academy of Machinery Equipment Beijing 100089China

An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of the fragments *** study investigated the fragmentation performance of a new high-carbon silicon-manganese(HCSiMn)steel cylindrical shell through fragment recovery *** with the conventional 45Cr steel shell,the number of small mass fragments produced by the HCSi Mn steel shell was significantly increased with a scale parameter of 0.57 g fitted by the Weibull distribution *** fragmentation process of the HCSi Mn shell exhibited more brittle tensile fracture characteristics,with the microcrack damage zone on the outer surface being the direct cause of its high *** the one hand,the doping of alloy elements resulted in grain refinement by forming metallographic structure of tempered sorbite,so that microscopic intergranular fracture reduces the characteristic mass of the fragments;on the other hand,the distribution of alloy carbides can exert a"pinning"effect on the substrate grains,causing more initial cracks to form and propagate along the brittle carbides,further improving the shell *** the killing power radius for light armored vehicles was slightly reduced by about 6%,the dense killing radius of HCSiMn steel projectile against personnel can be significantly increased by about 26%based on theoretical *** results provided an experimental basis for high fragmentation warhead design,and to some extent,revealed the correlation mechanism between metallographic structure and shell fragmentation.

关键词： Projectile fragmentation Fragment mass distribution Fracture mode Metallographic structure Damage power

Recovery and in-situ reduction of precious metals by graphdiyne and graphdiyne oxide for antibacterial use

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Rare Metals 2024年第4期43卷 1747-1757页

作者： Ming-Ji Jiang Ya-Na Zhang Ling-Shen meng Jing kang Yong-Jun Li Alideertu Dong College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot010021China Engineering Research Center of Dairy Quality and Safety Control Technology Ministry of EducationInner Mongolia UniversityHohhot010021China Department of Chemistry University of ZurichCH-8057ZurichSwitzerland Laboratory of Organic Solids and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China

Based on the in-situ self-reduction and chemical stability,graphdiyne(GDY)and graphdiyne oxide(GDYO)are used as trapping agents to investigate the ability for recovering Au^(3+),Ag^+,and Pd^(2+)under different pH values and interfering *** strong acidity at pH=1,these two agents demonstrate high select recovery towards the three precious metal ions,which could be insitu reduced to nanoparticles(NPs).In addition,superparamagnetic Fe_(3)O_(4)NPs are deposited on the surfaces of GDY and *** magnetic responses enable GDYFe_(3)O_(4)to recover precious metals conveniently and efficiently by the aid of an external magnetic *** study also confirms the antibacterial activity of the as-recovered NPs deposited on GDY and GDYO against Escherichia coli and Staphylococcus aureus(1×10^(5)colony-forming unit(CFU)·mL^(-1)),and the antibacterial rates are 100%.This strategy of recovering precious metals and subsequently reusing to combat pathogens will be of great significance for environmental remediation and biomedical applications.

关键词： Graphdiyne In-situ reduction Recovery Precious metals Antibacterial

Calcium-based polymers for suppression of soil acidification by improving acid-buffering capacity and inhibiting nitrification

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Journal of Environmental Sciences 2024年第5期139卷 138-149页

作者： Fei kang yunshan meng Yanning Ge yun Zhang Haixiang Gao Xueqin Ren Jie Wang Shuwen Hu Beijing Key Laboratory of Farmland Soil Pollution Prevention-control and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Applied Chemistry China Agricultural UniversityBeijing 100193China

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical *** and environmentally friendly materials,such as calcium lignosulfonate(CaLS),calcium poly(aspartic acid)(PASP-Ca),and calcium polyγ-glutamic acid(γ-PGA-Ca),are known to effectively ameliorate soil ***,their effectiveness in inhibiting soil acidification has not been *** study aimed to evaluate the effect of CaLS,PASP-Ca,andγ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly(i.e.,via nitrification)caused by the application of HNO_(3)and urea,*** comparison,Ca(OH)_(2)and lignin were used as the inorganic and organic controls,*** the materials,γ-PGA-Ca drove the substantial improvements in the pH buffering capacity(pHBC)of the soil and exhibited the greatest potential in inhibiting HNO_(3)-induced soil acidification via protonation of carboxyl,complexing with Al~(3+),and cation exchange *** acidification induced by urea,CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during ***,the sharp reduction in the population sizes of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)confirmed the inhibition of nitrification via CaLS ***,compared to improving soil pHBC,CaLS may play a more important role in suppressing indirect ***,γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO_(3) addition,whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting *** conclusion,these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.

关键词： Calcium-based polymer Soil acidification pH buffering capacity Nitrification inhibition

Aspartoacylase suppresses prostate cancer progression by blocking LYN activation

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Military Medical Research 2024年第2期11卷 180-205页

作者： Hong Weng kang-Ping Xiong Wang Wang Kai-yu Qian Shuai yuan Gang Wang Fang yu Jun Luo meng‑Xin Lu Zhong‑Hua Yang Tao Liu Xing Huang Hang Zheng Xing-Huan Wang Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Center for Evidence‑Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Biological Repositories Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Key Laboratory of Tumor Biological Behaviors Wuhan 430071China Department of Pathology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Center for Pathology and Molecular Diagnostics Wuhan UniversityWuhan 430071China Wuhan Research Center for Infectious Diseases and Cancer Chinese Academy of Medical SciencesWuhan 430071China

Background:Globally,despite prostate cancer(PCa)representing second most prevalent malignancy in male,the precise molecular mechanisms implicated in its pathogenesis remain ***,elucidating the key molecular regulators that govern disease progression could substantially contribute to the establishment of novel therapeutic strategies,ultimately advancing the management of ***:A total of 49 PCa tissues and 43 adjacent normal tissues were collected from January 2017 to December 2021 at Zhongnan Hospital of Wuhan *** advanced transcriptomic methodologies were employed to identify differentially expressed mRNAs in *** expression of aspartoacylase(ASPA)in PCa was thoroughly evaluated using quantitative real-time PCR and Western blotting *** elucidate the inhibitory role of ASPA in PCa cell proliferation and metastasis,a comprehensive set of in vitro and in vivo assays were conducted,including orthotopic and tumor-bearing mouse models(n=8 for each group).A combination of experimental approaches,such as Western blotting,luciferase assays,immunoprecipitation assays,mass spectrometry,glutathione S-transferase pulldown experiments,and rescue studies,were employed to investigate the underlying molecular mechanisms of ASPA's action in *** Student‘s t-test was employed to assess the statistical significance between two distinct groups,while one-way analysis of variance was utilized for comparisons involving more than two groups.A two-sided P<0.05 was deemed to indicate statistical ***:ASPA was identified as a novel inhibitor of PCa *** expression of ASPA was found to be significantly down-regulated in PCa tissue samples,and its decreased expression was independently associated with patients’prognosis(HR=0.60,95%CI 0.40–0.92,P=0.018).Our experiments demonstrated that modulation of ASPA activity,either through gain-or loss-of-function,led to the suppression or enhancement of PCa cell proliferation,mig

关键词： Prostate cancer Aspartoacylase LYN JNK AP-1 C-Jun Phosphorylation

Two Monte Carlo-based simulators for imaging-system modeling and projection simulation of flat-panel X-ray source

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Nuclear Science and Techniques 2024年第7期35卷 31-46页

作者： meng-Ke Qi Ting He Yi-Wen Zhou Jing kang Zeng-Xiang Pan Song kang Wang-Jiang Wu Jun Chen Ling-Hong Zhou yuan Xu School of Biomedical Engineering Southern Medical UniversityGuangzhou510515China State Key Laboratory of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and TechnologySchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou510275China Department of Radiotherapy Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou510515China

The advantages of a flat-panel X-ray source(FPXS)make it a promising candidate for imaging *** imaging-system modeling and projection simulation are critical for analyzing imaging performance and resolving overlapping projection issues in *** conventional analytical ray-tracing approach is limited by the number of patterns and is not applicable to FPXS-projection ***,the computation time of Monte Carlo(MC)simulation is independent of the size of the patterned arrays in *** study proposes two high-efficiency MC projection simulators for FPXS:a graphics processing unit(GPU)-based phase-space sampling MC(gPSMC)simulator and GPU-based fluence sampling MC(gFSMC)*** two simulators comprise three components:imaging-system modeling,photon initialization,and physical-interaction simulations in the ***-system modeling was performed by modeling the FPXS,imaging geometry,and *** gPSMC simulator samples the initial photons from the phase space,whereas the gFSMC simulator performs photon initialization from the calculated energy spectrum and fluence *** entire process of photon interaction with the geometry and arrival at the detector was simulated in parallel using multiple GPU kernels,and projections based on the two simulators were *** accuracies of the two simulators were evaluated by comparing them with the conventional analytical ray-tracing approach and acquired projections,and the efficiencies were evaluated by comparing the computation *** results of simulated and realistic experiments illustrate the accuracy and efficiency of the proposed gPSMC and gFSMC simulators in the projection calculation of various phantoms.

关键词： Flat-panel X-ray source(FPXS) Imaging-system modeling Projection simulation Monte Carlo-based simulators

Enhancement and Removal of PM_(2.5)by Cold and Warm Air Masses Accompanying Certain Synoptic Weather Systems across Hangzhou,China during 2014-2020

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Journal of Meteorological Research 2024年第3期38卷 620-634页

作者： Bu yu Feng CHEN Hanqing kang Bin ZHU Hongnian LIU Hangzhou Meteorological Bureau Hangzhou310051China Hangzhou International Urbanology Research Center for Urban Governance Studies Hangzhou311121China Zhejiang Institute of Meteorological Sciences Hangzhou310008China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing210044China School of Atmospheric Sciences Nanjing UniversityNanjing210023China

Local air pollution is strongly affected by synoptic weather systems,such as fronts,troughs,low-altitude vortices,or high-altitude ***,few studies have analyzed the meteorological properties of cold or warm air masses associated to these systems and their impact on local air *** this study,hourly observations of fine particulate matter(diameter of up to 2.5µm,i.e.,PM_(2.5)),wind(V),temperature(T),pressure(P),and precipitation(R),acquired in Hangzhou in 2014-2020,were *** this analysis,weather patterns were categorized into 27 types;89 and 94 cases illustrating the passage of warm and cold air masses over Hangzhou were identified,respectively;the influence of air mass temperature,wind speed,and wind direction on PM_(2.5) concentrations and local accumulation or removal was *** main results are as follows.(1)Pollution events occurred more frequently for cold than for warm air masses,but average pollutant concentration was lower for cold air masses;(2)48%of the cold air mass cases corresponded to PM_(2.5) decreases and 52%to PM_(2.5) increases,with strong cold air masses(ΔT_(24h)>4°C;∣V∣_(average)>4 m s^(−1))markedly reducing local pollution,but weak cold air masses(ΔT24h4°C)reduced the PM_(2.5) concentration whereas weaker winds(∣V∣_(average)<2 m s^(−1))increased it;and(4)PM_(2.5) concentration decreased sharply within 4 h after the passage of strong cold air masses,but more gradually within 14 h after the passage of strong warm air *** results considerably improve the current understanding of the influence of cold and warm air masses on local pollution patterns.

关键词： weather type air mass enhancement removal meteorological condition