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A polymyxin B loaded hypoxia-responsive liposome with improved biosafety for efficient eradication of bacterial biofilms

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Nano Research 2024年第9期17卷 8325-8336页

作者： Fang Liu Lingyun Zou Yongcheng Chen Zuolong Liu Yue Huang qiao jin jian ji MOE Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Transvascular Implantation Devices The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310009China

Biofilm-associated bacterial infection brings serious threats to global public health owing to serious antibiotic *** is urgently needed to develop innovative strategies to combat biofilm-associated bacterial *** stand out as the last line of defense against Gram-negative ***,serious nephrotoxicity of polymyxins severely limits their clinical ***,a hypoxia-responsive liposome is designed as the nanocarrier of polymyxin B(PMB)to combat biofilms developed by Gram-negative bacteria.A metronidazole modified lipid(hypoxia-responsive lipid(HRLipid))is synthesized to fabricate hypoxia-responsive liposomes(HRLip).PMB loaded hypoxia-responsive liposomes(HRL-PMB)is then prepared to mitigate the nephrotoxicity of PMB while preserving its excellent bactericidal ***-PMB shows very low hemolysis and cytotoxicity due to liposomal encapsulation of *** can be readily released from HRL-PMB in response to hypoxic biofilm microenvironment,exerting its bactericidal activity to realize biofilm *** excellent in vivo antibiofilm ability of HRL-PMB is confirmed by a Pseudomonas aeruginosa infected zebrafish model and a *** pneumonia infection ***,HRL-PMB can greatly reduce the nephrotoxicity of PMB after intravenous *** hypoxia-sensitive liposomes held great promise to improve the biosafety of highly toxic antibiotics while preserving their intrinsic bactericidal ability,which may provide an innovative strategy for combating biofilm-associated infections.

关键词： bacterial biofilm hypoxia liposome polymyxin B nephrotoxicity

Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： chao LIANG Shichao ji Yingchang CAO Keyu LIU jing WU Fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their *** on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this *** the microscopic scale,each type of pyrite is associated with a different formation *** are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous *** pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal *** morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron *** addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen ***,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element

Thermal History of Cambrian Burgess Shale-Type Deposits:New Insights from the Early Cambrian Chengjiang and Qingjiang Fossils of South China

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Journal of Earth Science 2024年第4期35卷 1215-1223页

作者： Yuheng qiao Linhao Cui Guangyuan Xing Dongjing Fu chao Chang Robert Gaines Xingliang Zhang State Key Laboratory of Continental Dynamics Shaanxi Key laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an710069China Department of Geology Pomona CollegeClaremontCA91711USA

Burgess Shale-type deposits provide a wealth of information on the early evolution of *** that are central to understanding the exceptional preservation of these biotas and the paleoenvironments they inhabited may be obscured by the post-depositional alteration due to metamorphism at depth and weathering near the Earth’s *** over 50 Cambrian BST biotas,the Chengjiang and Qingjiang deposits are well known for their richness of soft-bodied taxa,fidelity of preservation,and Early Cambrian *** alteration via weathering has been well-investigated,the thermal maturity of the units bearing the two biotas has not yet been *** we investigate peak metamorphic temperatures of the two deposits using two independent *** gradient analyses demonstrate that the most fossiliferous sections of the Chengjiang were buried at a maximum depth of∼8500 m in the Early Triassic,corresponding to∼300°C,while the type area of the Qingjiang biota was buried at a maximum depth of∼8700 m in the Early Jurassic,corresponding to∼240°*** geothermometer analyses of fossil carbonaceous material demonstrate that peak temperatures varied across localities with different burial *** two productive sections of the Chengjiang biota were thermally altered at a peak temperature of approximately 300°C,and the main locality of the Qingjiang biota experienced a peak temperature of 238±22°*** results from two independent methods are *** BST deposits for which thermal maturity has been documented,the Qingjiang biota is the least thermally mature,and therefore holds promise for enriching our understanding of BST deposits.

关键词： the Chengjiang Biota the Qingjiang Biota burial history Raman geothermometer thermal history Burgess Shale-type Lagerstätte

Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： Wen-Peng Bai Shi-Qing Cheng Xin-Yang Guo Yang Wang qiao Guo chao-Dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

Mutual information oriented deep skill chaining for multi‐agent reinforcement learning

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 1014-1030页

作者： Zaipeng Xie Cheng ji Chentai qiao WenZhan Song Zewen Li Yufeng Zhang Yujing Zhang Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjingChina College of Computer and Information Hohai UniversityNanjingChina Center for Cyber‐Physical Systems University of GeorgiaAthensGeorgiaUSA Information Networking Institute Carnegie Mellon UniversityPittsburghPennsylvaniaUSA Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPennsylvaniaUSA

Multi‐agent reinforcement learning relies on reward signals to guide the policy networks of individual ***,in high‐dimensional continuous spaces,the non‐stationary environment can provide outdated experiences that hinder convergence,resulting in ineffective training performance for multi‐agent *** tackle this issue,a novel reinforcement learning scheme,Mutual Information Oriented Deep Skill Chaining(MioDSC),is proposed that generates an optimised cooperative policy by incorporating intrinsic rewards based on mutual information to improve exploration *** rewards encourage agents to diversify their learning process by engaging in actions that increase the mutual information between their actions and the environment *** addition,MioDSC can generate cooperative policies using the options framework,allowing agents to learn and reuse complex action sequences and accelerating the convergence speed of multi‐agent *** was evaluated in the multi‐agent particle environment and the StarCraft multi‐agent challenge at varying difficulty *** experimental results demonstrate that MioDSC outperforms state‐of‐the‐art methods and is robust across various multi‐agent system tasks with high stability.

关键词： artificial intelligence techniques decision making intelligent multi‐agent systems

Upconverting and downshifting circularly polarized luminescence in a superstructural helix

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Science China Chemistry 2024年第8期67卷 2571-2577页

作者： Honghan ji Bin Wu Enquan Tian chao Ren Xue jin Liangliang Zhu Pengfei Duan CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China University of Chinese Academy of Sciences Beijing 101408China

The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembly of an upconversion system,incorporating one sensitizer(Pt(II) mesotetraphenyl tetrabenzoporphyrine, Pt TPBP) and two annihilators(R/S-DPA and R/SBDP) within liquid crystals. The chiral nature of the annihilators induces a transformation of the nematic liquid crystal into chiral nematic liquid crystals(N*LC), establishing an excellent chiral matrix. Upon the incorporation of the sensitizer Pt TPBP and subsequent excitation at 635 nm, the system demonstrates two independent triplet–triplet annihilation photon upconversion(TTA-UC) with the emission in blue and yellow, aided by thermally activated triplet–triplet energy transfer(TTET). This is accompanied by the simultaneous generation of upconverting circularly polarized luminescence(UC-CPL) and downshifting near-infrared circularly polarized luminescence(DS-CPL) originating from the residual luminescence of Pt TPBP. Remarkably,fine-tuning the ratio between the two annihilators allows the TTA-UC system to exhibit multicolor CPL emission with an amplified luminescence dissymmetry factor(glum, reaching up to 0.6). Our study unveils a previously unreported “one-excitation-to-three-emissions” system and provides a versatile strategy for modulating CPL emissions, surpassing conventional methodologies.

关键词： circularly polarized luminescence triplet–triplet annihilation upconversion near-infrared emission chiral nematic liquid crystal luminescence dissymmetry factor

Effect of solute Ce,Mn,and Si on mechanical properties of silicon steel:insights from DFT calculations

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Journal of Iron and Steel Research International 2024年第3期31卷 700-709页

作者： Xiang-jun Liu ji-chun Yang Hui-ping Ren Xiao-bin jia Ming-yi Zhang Chang-qiao Yang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resource Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Inner Mongolia North Heavy Industries Group Co. Ltd.Baotou 014010Inner MongoliaChina Inner Mongolia Metal Material Research Institute Baotou 014010Inner MongoliaChina

The influence of solute Ce,Mn,and Si on the mechanical properties of silicon steel was investigated by first-principles ***,Mn,and Si can all be solubilized in Fe *** significantly reduces the incompressibility and rigidity of the system but also significantly improves the toughness and *** effect of Mn on mechanical properties of the system is not *** has a significant effect on the improvement in incompressibility and rigidity but a limited effect on the improvement in toughness and *** metallic bond strength of Fe-Ce,Fe-Mn,and Fe-Si doped systems is weaker than that of the pure Fe system,which can be used to explain the reduction in the incompressibility and rigidity of these doped *** relatively high electron cloud density in the doped system may be responsible for the increase in toughness.

关键词： Silicon steel Rare earth First-principles calculation Elastic modulus Electronic structure

Zero thermal expansion in Cs_(2)W_(3)O_(10)

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Chinese Chemical Letters 2024年第7期35卷 538-541页

作者： Juan Guo Mingyuan Fang Qingsong Liu Xiao Ren Yongqiang qiao Mingju chao Erjun Liang Qilong Gao School of Physics&Microelectronics Key Laboratory of Materials Physics of Ministry of Education of ChinaZhengzhou UniversityZhengzhou 450052China

Zero thermal expansion materials are important for the practical applications due to their shape stability as changing *** reported concept of average atomic volume is an available method to hunt new zero thermal expansion ***,according to this concept,a tetragonal tungstate Cs_(2)W_(3)O_(10)with zero expansion has been *** is no structure phase transition as increasing temperature from 150 K to 573 *** coefficient of thermal expansion of axes and volume areαa=0.0074×10^(-6)K^(-1),αc=1.63×10^(-6)K^(-1),andαV=1.60×10^(-6)K^(-1),respectively,in the temperature range of 150~573 *** temperature-and pressure-dependent Raman spectra reveal that the vibrations of WO6octahedra libration modes with positive total anharmonicity and W-O-W bending mode with negative Grüneisen parameter are possibly the origin of zero thermal expansion in Cs_(2)W_(3)O_(10).

关键词： Zero thermal expansion Cesium tungstate Raman spectra Average atomic volume Temperature-dependent X-ray diffraction

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： Xing-Xing qiao Yu-Hang Xu Xiang-ji Liu Sai-Le Chen Zhou Zhong Ya-Feng Li jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment ***,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton *** to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical *** work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis