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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

Efficient and stable hybrid perovskite-organic lightemitting diodes with external quantum efficiency exceeding 40 per cent

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Light(Science & Applications) 2024年第7期13卷 1364-1371页

作者： Lingmei Kong Yun Luo Qianqian Wu Xiangtian Xiao Yuanzhi Wang Guo Chen Jianhua Zhang Kai Wang wallace CHChoy Yong-Biao Zhao Hongbo Li takayuki Chiba Junji Kido Xuyong Yang Key Laboratory of Advanced Display and System Applications of Ministry of Education Shanghai UniversityShanghai 200072China. Institute of Nanoscience and Applications Department of Electrical and Electronic EngineeringSouthern University of Science and TechnologyShenzhen 518055China. Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina. Department of Physics and Lakeside AR/VR Laboratory International Joint Research Center for Optoelectronic and Engineering ResearchYunnan UniversityKunming 650091China. Experimental Center of Advanced Materials School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China. Graduate School of Organic Materials Science Frontier Center for Organic MaterialsYamagata University4-3-16 JonanYonezawa 992–8510Japan

Light-emitting diodes(LEDs)based on perovskite semiconductor materials with tunable emission wavelength in visible light range as well as narrow linewidth are potential competitors among current light-emitting display technologies,but still suffer from severe instability driven by electric ***,we develop a stable,efficient and highcolor purity hybrid LED with a tandem structure by combining the perovskite LED and the commercial organic LED technologies to accelerate the practical application of *** LED and organic LED with close photoluminescence peak are selected to maximize photon emission without photon reabsorption and to achieve the narrowed emission *** designing an efficient interconnecting layer with p-type interface doping that provides good opto-electric coupling and reduces Joule heating,the resulting green emitting hybrid LED shows a narrow linewidth of around 30 nm,a peak luminance of over 176,000 cd m^(−2),a maximum external quantum efficiency of over 40%,and an operational half-lifetime of over 42,000 h.

关键词： diodes narrow quantum

Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat t Nguyen Princess Margaret Cancer Centre University Health NetworkTorontoOntarioCanada

Objective:to investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,Pthis study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam

验证自由呼吸MR扩散加权成像和动态对比增强MRI在具有实性肿瘤儿童评估中的可重复性:一项实验性研究

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国际医学放射学杂志 2015年第6期 596-597页

作者： K.Miyazaki N.P.Jerome D.J.Collins M.R.Orton J.A.d 'Arcy t.wallace 陈丽华 Cancer Research UK Cancer Imaging Centre at the Institute of Cancer Research

摘要目的本研究旨在检测包括MRI扩散加权成像(DWI)和动态增强MRI(DCE-MRI)的功能MRI的定量参数评估儿童实性肿瘤的可重复性。方法确诊为实性肿瘤的16

关键词：扩散加权成像 MRI 可重复性动态对比实性肿瘤自由呼吸实验性研究定量参数表观扩散系数细胞外容积

A novel strategy for ionomer coating of Ag nanoparticles used for the electrochemical reduction of CO2 to CO in a membrane electrode assembly

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National Science Review 2024年第2期11卷 94-95页

作者： Alexis t.Bell Department of Chemical and Biomolecular Engineering University of California

the electrochemical reduction of the CO2reaction （CO2RR） offers an attractive means for converting the carbon content of CO2, released from a stationary source or the atmosphere, into fuels and chemicals [1]. Utiliz...

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A deep neural network based surrogate model for damage identification in full-scale structures with incomplete noisy measurements

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 393-410页

作者： tram BUI-NGOC Duy-Khuong LY tam t tRUONG Chanachai tHONGCHOM t.NGUYEN-tHOI Laboratory for Computational Mechanics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Mechanical-Electrical and Computer Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Department of Computer Science Aarhus UniversityAarhus 8000Denmark thammasat University research unit in structural and foundation engineering Department of Civil EngineeringThammasat UniversityPathumthani 12120Thailand Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam thammasat School of Engineering Thammasat UniversityPathumthani 12120Thailand

the paper introduces a novel approach for detecting structural damage in full-scale structures using surrogate models generated from incomplete modal data and deep neural networks(DNNs).A significant challenge in this field is the limited availability of measurement data for full-scale structures,which is addressed in this paper by generating data sets using a reduced finite element(FE)model constructed by SAP2000 software and the MAtLAB programming *** surrogate models are trained using response data obtained from the monitored structure through a limited number of measurement *** proposed approach involves training a single surrogate model that can quickly predict the location and severity of damage for all potential *** achieve the most generalized surrogate model,the study explores different types of layers and hyperparameters of the training algorithm and employs state-of-the-art techniques to avoid overfitting and to accelerate the training *** approach’s effectiveness,efficiency,and applicability are demonstrated by two numerical *** study also verifies the robustness of the proposed approach on data sets with sparse and noisy measured ***,the proposed approach is a promising alternative to traditional approaches that rely on FE model updating and optimization algorithms,which can be computationally *** approach also shows potential for broader applications in structural damage detection.

关键词： vibration-based damage detection deep neural network full-scale structures finite element model updating noisy incomplete modal data

CompactChain:an efficient stateless chain for UtXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： B Swaroopa REDDY t Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UtXO(Unspent transaction Output)based blockchain systems into two RSA *** first accumulator is called transaction Output(tXO)commitment which represents the tXO *** second one is called Spent transaction Output(StXO)commitment which represents the StXO *** this work,we discuss three algorithms:(i)to update the tXO and StXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)to prove the transaction’s validity by providing a membership witness in tXO commitment and non-membership witness against StXO commitment for a coin being spent by a user;(iii)to update the witness for the coin that is not yet spent;the experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(transactions per second(tPS)).

关键词： stateless blockchain RSA Accumulator StXO commitment tXO commitment UtXO Non-interactive Proof of Exponentiation(NI-PoE) transactions per second(tPS)

Evaluation of red soil-bentonite mixtures for compacted clay liners

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 697-710页

作者： A.S.Devapriya t.thyagaraj Department of Civil Engineering Indian Institute of Technology MadrasChennai600036India

Compacted clay liners are an integral part of the waste landfills,which are provided to contain the leachate within the landfills and protect the surrounding ***,locally available natural soils are used for the construction of compacted clay liners if they satisfy the design ***,not all soils in their natural state satisfy all the design criteria for the liner ***,there is a definite need to modify the locally available natural soils by blending with bentonite to meet the required design criteria for the *** view of this,the present study evaluates the suitability of an Indian red soil enhanced with bentonite as a liner *** achieve this,a series of experiments were carried out using locally available red soil and ***,the suitability of the red soil was evaluated as a liner *** experimental results showed that the red soil met all the selection criteria stipulated by the Environmental Protection Agencies(EPAs)for the liners except the hydraulic conductivity ***,the red soil was mixed with bentonite contents of 10%,20%and 30%,and the red soil-bentonite mixtures were evaluated for their suitability for liners in their compacted ***,as the liners in the arid and semi-arid regions are subjected to moisture variations due to seasonal moisture fluctuations and other factors,the red soil-bentonite mixtures were subjected to wetdry cycles,and their suitability was evaluated after wet-dry *** experimental results revealed that all the red soil-bentonite mixtures met the stipulated EPA criteria for the liners in the as-compacted ***,the red soil-bentonite mixtures with 20%and 30%bentonite contents only satisfied the hydraulic conductivity requirement even after wet-dry *** experimental findings were supplemented with the microstructural insights captured through digital camera images,scanning electron microscopy(SEM),and mercury intrusion porosimetry(M

关键词： Compacted clay lines Hydraulic conductivity Wet-dry cycles Microstructure