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Influence of group B streptococcus and vaginal cleanliness on the vaginal microbiome of pregnant women

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World Journal of Clinical Cases 2022年第34期10卷 12578-12586页

作者： Qi Liao Xiao-Fen Zhang Xin Mi Feng Jin Hong-Min Sun qing-xuan wang Department of Obstetrics and Gynecology Shunyi Maternal and Children’s Hospital of Beijing Children’s HospitalBeijing 101300China Department of Genetics and Reproductive Medicine Shunyi Maternal and Children’s Hospital of Beijing Children’s HospitalBeijing 101300China

BACKGROUND The vaginal microbiome plays a critical role in the health of pregnant women and their *** B Streptococcus(GBS)and vaginal cleanliness significantly affect the vaginal microecosystem and are closely associated with vaginal *** To explore the effects of GBS status and vaginal cleanliness on vaginal *** We collected 160 vaginal swabs from pregnant women and divided them into the following four groups based on GBS status and vaginal cleanliness:GBS-positive+vaginal cleanliness I–II degree,GBS-negative+vaginal cleanliness I–II degree,GBS-positive+vaginal cleanliness III–IV degree,and GBS-negative+vaginal cleanliness III–IV *** were subjected to 16S rRNA gene amplicon *** Alpha diversity analysis showed that the Shannon index did not significantly differ between the four *** identified significant variation in taxa abundance between the GBS-positive and GBS-negative groups and between the vaginal cleanliness I–II degree and III–IV degree *** coordinate analysis and non-metric multidimensional scaling analysis further confirmed the microbial diversity of the four ***,the linear discriminant analysis demonstrated that Lactobacillus jensenii and Actinobacteria were strongly associated with GBS-positive status,and Lactobacillus iners,Lactobacillaceae,Lactobacillus,Lactobacillales,Bacilli and Firmicutes were closely correlated with GBS-negative *** GBS status and vaginal cleanliness significantly affect vaginal microbiome differences in pregnant *** findings provide instructional information for clinical antibiotic treatment in pregnant women with different GBS statuses and vaginal cleanliness degrees.

关键词： Vaginal microbiome Pregnant women 16S rRNA gene amplicon sequencing Group B Streptococcus Vaginal cleanliness

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang wang Jia Zhang Shi-Long Yang Ze-xuan Xu Shi-qing Cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil *** contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective ***,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant *** this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer *** hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer *** combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir *** with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore *** field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and th

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis

Escape probability for isotropic emitters near Kerr black hole with astrometric

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Communications in Theoretical Physics 2024年第5期76卷 128-133页

作者： Yu-xuan Han qing-Hua Zhu qing-Guo Huang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan RoadBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCASHangzhou 310024China

The paper investigates the escape probability for isotropic emitters near a Kerr black *** propose a new approach to obtain the escape probability in a general manner,going beyond previous case-by-case *** approach is based on studies of the black hole shadow with astrometric observable and can be applied to emitters with an arbitrary 4-velocities and locations,even to the emitters outside of the equatorial *** also consider representative examples illustrating how escape probabilities vary with distance,velocity,and inclination ***,this new approach provides an effective method for studying escape probabilities near Kerr black holes.

关键词： Kerr black hole photon escape probability isotropic emitters

An ultrafast rechargeable hybrid potassium dual-ion capacitor based on carbon quantum dot@ultrathin carbon film cathode

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Rare Metals 2024年第10期43卷 5070-5081页

作者： Zhao-Meng Liu Da wang Shang-Zhuo Li qing-Song Lai Dong-Run Yang Lu-Kang Zhao Jian-Jia Mu xuan-Chen wang xuan-Wen Gao Wen-Bin Luo Institute for Energy Electrochemistry and Urban Mines Metallurgy School of MetallurgyNortheastern University Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University

Ultrafast rechargeable hybrid potassium dualion capacitors （HPDICs） were designed by employing carbon quantum dot@ultrathin carbon film （CQD@CF） as the cathode *** designed CQD@CF is selfassembled by a simple catalytic graphitization route followed by an acid leaching *** special composite features a large adsorption interface,a remarkable anion hybrid storage capability and outstanding structure *** electrochemical performance of CQD@CF composite is fully tapped in a half-cell system at the operating voltage between 1.4 and 4.5 V,achieving an admirable specific discharge capacity of 128.5 mAh·g-1a 50 mA·g-1,an ultra-high capacity retention ratio of 97.97% after cycling 5000 times at 1000 mA·g-1and a 96.10%high capacity retention ratio after cycling 40,000 times at 5000 mA·g-1,***,with the support of ex situ TEM and XPS,the structural stability principle and anionic hybrid storage mechanism of CQD@CF electrode are investigated *** the full-cell system,HPDICs with the CQD@CF as cathode and nanographite powder as anode also present a 141.5 Wh·kg-1high energy density,a 5850 W·kg-1power density and a super-long cycle stability (90.2% capacity retention ratio after cycling 30,000 times at 5000 mA·g-1).

关键词： Anion hybrid storage mechanism Carbon quantum dots Potassium dual ion capacitor Ultrafast rechargeable Ultrathin carbon film

Enhanced Sensing Mechanism Based on Shifting an Exceptional Point

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Research 2024年第3期6卷 285-292页

作者： xuan Mao Guo-qing Qin Hao Zhang Bo-Yang wang Dan Long Gui-Qin Li Gui-Lu Long Department of Physics State Key Laboratory of Low-Dimensional Quantum PhysicsTsinghua UniversityBeijing 100084China Beijing Institute of Radio Measurement The Second Academy of China Aerospace Science and Industry Corporation(CASIC)Beijing 100854China Purple Mountain Laboratories Nanjing 21111China Frontier Science Center for Quantum Information Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100193China

Non-Hermitian systems associated with exceptional points (EPs) are expected to demonstrate a giant response enhancement for various sensors. The widely investigated enhancement mechanism based on diverging from an EP should destroy the EP and further limits its applications for multiple sensing scenarios in a time sequence. To break the above limit, here, we proposed a new enhanced sensing mechanism based on shifting an EP. Different from the mechanism of diverging from an EP, our scheme is an EP nondemolition and the giant enhancement of response is acquired by a slight shift of the EP along the parameter axis induced by perturbation. The new sensing mechanism can promise the most effective response enhancement for all sensors in the case of multiple sensing in a time sequence. To verify our sensing mechanism, we construct a mass sensor and a gyroscope with concrete physical implementations. Our work will deepen the understanding of EP-based sensing and inspire designing various high-sensitivity sensors in different physical systems.

关键词： mechanism shifting exceptional

Features and formulae of sediment incipient motion in vegetated flow environment

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Journal of Hydrodynamics 2024年第2期36卷 331-339页

作者： Yu-xuan Xu Wei-jie wang Shi-bao Zhang Han-qing Zhao Xue-kai Chen Hai-ping Zhang School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou450045China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China

Aquatic vegetation is a vital component of natural river ecosystems,playing a crucial role in maintaining ecological balance,providing habitat and improving water ***,the presence of vegetation results in increased resistance in vegetated channels compared with non-vegetated channels,rendering traditional sediment movement predictions inadequate for the ***,the concept of a vegetation influence factor,denoted by CDah,has been proposed by previous researchers to represent the effect of vegetation on sediment movement in *** this study,we focus on exploring the vegetation resistance coefficient(CD)among the vegetation influence factors,evaluating two different calculation methods for vegetation resistance coefficient,and presenting two expressions through genetic algorithm analysis to predict the incipient flow velocity of sediment in vegetated *** predicted values from the new formulae show excellent agreement with measured data,highlighting the high accuracy of the proposed methods in predicting the incipient flow velocity of *** results provide a solid theoretical basis for understanding the influence of aquatic vegetation on sediment particle movement.

关键词： Vegetation flow vegetation resistance coefficient genetic algorithm sediment initiation

Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： Bei Zhang xuan Zhang Jian wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

When Does Sora Show:The Beginning of TAO to Imaginative Intelligence and Scenarios Engineering

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 809-815页

作者： Fei-Yue wang qinghai Miao Lingxi Li qinghua Ni xuan Li Juanjuan Li Lili Fan Yonglin Tian qing-Long Han School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190China Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China Department of Electrical and Computer Engineering Indiana University-Purdue University IndianapolisIndianapolisIN 46202USA Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China Virtual Reality Fundamental Research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

DURING our discussion at workshops for writing“What Does ChatGPT Say:The DAO from Algorithmic Intelligence to Linguistic Intelligence”[1],we had expected the next milestone for Artificial Intelligence(AI)would be in the direction of Imaginative Intelligence(II),i.e.,something similar to automatic wordsto-videos generation or intelligent digital movies/theater technology that could be used for conducting new“Artificiofactual Experiments”[2]to replace conventional“Counterfactual Experiments”in scientific research and technical development for both natural and social studies[2]-[6].Now we have OpenAI’s Sora,so soon,but this is not the final,actually far away,and it is just the beginning.

关键词： something Intelligence replace

Application of nanoscale metal–organic frameworks in tumor immunotherapy

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Rare Metals 2024年第10期43卷 4867-4883页

作者： Xiao-xuan Zeng Jing-Sheng Lu Dong-Wei Ma Yu-Ting Huang Ling Chen Gang wang qing Chen Ning Lin College of Pharmacy Guangxi Scientific Research Center of Traditional Chinese MedicineGuangxi University of Chinese Medicine Guangxi Zhuang Yao Medicine Center of Engineering and Technology

Immunotherapy has attracted wide attention because it can not only kill tumor cells but also effectively prevent tumor recurrence. However, due to the poor efficacy of the monotherapy in tumor immunotherapy, combination therapies are needed to enhance their efficacy,such as chemodynamic therapy/immunotherapy, photodynamic therapy/immunotherapy, sonodynamic therapy/immunotherapy and so on. Nanoscale metal–organic frameworks(nMOFs) are widely used for drug delivery because of their rich and variable composition, high drug loading capacity and good biodegradability. Compared with other conventional drug delivery systems(DDSs),nMOFs play more advantageous role in inducing immune cell death of tumor cells and combination therapies. This article focuses on the application of n MOFs in tumor immunotherapy in terms of their use as gatekeepers, supplementary agents and drug carriers, respectively, with the aim of providing some ideas and references for the design of smart nanoscale DDS for tumor immunotherapy.

关键词： Drug delivery system Immunotherapy Metal–organic frameworks Tumor