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Science China Earth sciences 2024年第7期67卷 2226-2241页

作者： Min YANG Peilong YU lifeng zhang xiaobing PAN Quanjia ZHONG Yunying LI College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory of High Impact Weather(Special) China Meteorological AdministrationChangsha 410073China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China Department of Ocean Science Hong Kong University of Science and TechnologyHong Kong 999077China

The scale-dependent predictability of the devastating 7·20 extreme rainstorm in Zhengzhou,China in 2021 was investigated via ensemble experiments,which were perturbed on different scales using the stochastic kinetic-energy backscatter(SKEB)scheme in the WRF model,with the innermost domain having a 3-km grid *** daily rainfall(RAIN24h)and the cloudburst during 1600-1700 LST(RAIN1h)were *** demonstrated that with larger perturbation scales,the ensemble spread for the rainfall maximum widens and rainfall forecasts become closer to the *** ensembles with mesoscale or convective-scale perturbations,RAIN1h loses predictability at scales smaller than 20 km and RAIN24h is predictable for all *** in ensembles with synoptic-scale perturbations,the largest scale of predictability loss extends to 60 km for both RAIN1h and ***,the average positional error in forecasting the heaviest rainfall for RAIN24h(RAIN1h)was 400 km(50-60)*** southerly low-level jet near Zhengzhou was assumed to be directly responsible for the forecast uncertainty of *** rapid intensification in low-level cyclonic vorticity,mid-level divergence,and upward motion concomitant with the jet dynamically facilitated the *** analysis of the divergent,rotational and vertical kinetic spectra and the corresponding error spectra showed that the error kinetic energy at smaller scales grows faster than that at larger scales and saturates more quickly in all ***-scale perturbations not only boost larger-scale error growth but are also conducive to error growth at all scales through a downscale cascade,which indicates that improving the accuracy of larger-scale flow forecast may discernibly contributes to the forecast of cloudburst intensity and position.

关键词： Stochastic kinetic-energy backscatter(SKEB) Extreme rainfall Ensemble forecast Predictability

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A high-speed true random number generator based on Ag/SiNx/n-Si memristor

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Frontiers of physics 2024年第1期19卷 241-250页

作者： xiaobing Yan Zixuan zhang Zhiyuan Guan Ziliang fang Yinxing zhang Jianhui Zhao Jiameng Sun Xu Han Jiangzhen Niu Lulu Wang Xiaotong Jia Yiduo Shao Zhen Zhao Zhenqiang Guo Bing Bai Institute of life Science and Green Development Key Laboratory of Brain-Like Neuromorphic Devices and Systems of Hebei ProvinceCollege of Electron and Information EngineeringHebei UniversityBaoding 071002China

The intrinsic variability of memristor switching behavior can be used as a natural source of randomness,this variability is valuable for safe applications in hardware,such as the true random number generator(TRNG).However,the speed of TRNG is still be further ***,we propose a reliable Ag/SiNx/n-Si volatile memristor,which exhibits a typical threshold switching device with stable repeat ability and fast switching *** volatile-memristor-based TRNG is combined with nonlinear feedback shift register(NFSR)to form a new type of high-speed dual output ***,the bit generation rate reaches a high speed of 112 kb/*** addition,this new TRNG passed all 15 National Institute of Standards and Technology(NIST)randomness tests without post-processing steps,proving its performance as a hardware security *** work shows that the SiNx-based volatile memristor can realize TRNG and has great potential in hardware network security.

关键词： volatile memristor true random number generator(TRNG) delay time threshold switching device

Chronic administration of triclosan leads to liver fibrosis through hepcidin-ferroportin axis-mediated iron overload

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Journal of Environmental sciences 2024年第3期137卷 144-154页

作者： Jing Liu Lecong zhang fang Xu Ping zhang Yang Song College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China The Institute of Karst Wetland Ecology Guizhou Minzu UniversityGuiyang 550025China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Triclosan(TCS)has been manufactured as an antibacterial compound for half a ***,it is widely used in various personal care products;however,its potential adverse effects raise a lot of ***,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of *** discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic *** study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,*** by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron *** only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to *** study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,*** together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin ***,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver ***■,an iron scavenger,significantly ameliorates TCS-induced liver *** summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also *** significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.

关键词： Triclosan Iron metabolism Hepcidin Hepatotoxicity Liver fibrosis

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Kinetic model of vibration screening for granular materials based on biological neural network

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Particuology 2024年第5期88卷 98-106页

作者： Zhan Zhao Yan zhang fang Qin Mingzhi Jin School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Shandong Academy of Agricultural Machinery sciences Ji'nan250100China

The kinetic model is the theoretical basis for optimizing the structure and operation performance of vibration screening *** this paper,a biological neurodynamic equation and neural connections were established according to the motion and interaction properties of the material under vibration *** material feeding to the screen and the material passing through apertures were considered as excitatory and inhibitory inputs,respectively,and the generated stable neural activity landscape was used to describe the material distribution on the 2D screen *** dynamic process of material vibration screening was simulated using discrete element method(DEM).By comparing the similarity between the material distribution established using biological neural network(BNN)and that obtained using DEM simulation,the optimum coefficients of BNN model under a certain screening parameter were determined,that is,one relationship between the BNN model coefficients and the screening operation parameters was *** screening parameters were randomly selected,and the corresponding relationships were established as a ***,with straw/grain ratio,aperture diameter,inclination angle,vibration strength in normal and tangential directions as inputs,five independent adaptive neuro-fuzzy inference systems(ANFIS)were established to predict the optimum BNN model coefficients,*** training results indicated that ANFIS models had good stability and *** flexibility and adaptability of the proposed BNN method was demonstrated by modeling material distribution under complex feeding conditions such as multiple regions and non-uniform rate.

关键词： Kinetic model Material distribution Vibration screening Biological neural network DEM simulation Adaptive neuro-fuzzy inference systems

Discontinuous phase diagram of amorphous carbons

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National Science Review 2024年第4期11卷 164-171页

作者： YinBo Zhu ZhouYu fang ZhongTing zhang HengAn Wu CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

The short-range order and medium-range order of amorphous carbons demonstrated in experiments allow us to rethink whether there exist intrinsic properties hidden by atomic disordering. Here we presented six representative phases of amorphous carbons（0.1–3.4 g/cm3）, namely, disordered graphene network（DGN）, high-density amorphous carbon（HDAC）, amorphous diaphite（a-DG）, amorphous diamond（a-D）, paracrystalline diamond（p-D）, and nano-polycrystalline diamond（NPD）, respectively, classified by their topological features and microstructural characterizations that are comparable with experiments. To achieve a comprehensive physical landscape for amorphous carbons, a phase diagram was plotted in the sp3/sp2versus density plane, in which the counterintuitive discontinuity originates from the inherent difference in topological microstructures, further guiding us to discover a variety of phase transitions among different amorphous carbons. Intriguingly, the power law, log（sp3/sp2） ∝ ρn, hints at intrinsic topology and hidden order in amorphous carbons, providing an insightful perspective to reacquaint atomic disorder in non-crystalline carbons.

关键词： amorphous carbons disordered carbons phase diagram microstructural topology phase transition

Your personal choices in transportation and food are important for lowering carbon emissions

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 27-32页

作者： Bruce Logan fang zhang Wulin Yang Le Shi Institute of Energy and the Environment The Pennsylvania State UniversityUniversity ParkPA 16802USA School of Environment Tsinghua UniversityBeijing 100084China College of Environmental sciences and Engineering Peking UniversityBeijing 100871China College of Environmental and Resource sciences Zhejiang UniversityHangzhou 310058China

There is a global need to reduce greenhouse gas emissions to limit the extent of climate change.A better understanding of how our own activities and lifestyle influence our energy use and carbon emissions can help us enable changes in activities that can lead to reductions in carbon *** we discuss an approach based on examining carbon emissions from the perspective of the unit C,where 1 C is the CO_(2)from food a person would on average eat every *** approach shows that total CO_(2)emissions in China,normalized by the population,is 22.5 C while carbon emissions for a person in the US is 43.9 C.A better appreciation of our own energy use can be obtained by calculating carbon emissions from our own activities in units of C,for example for driving a car gasoline or electric vehicle a certain number of kilometers,using electricity for our homes,and eating different *** this information,we can see how our carbon emissions compare to national averages in different countries and make decisions that could lower our personal CO_(2)emissions.

关键词： Carbon dioxide Climate change Daily energy Greenhouse gas

Intensified warming suppressed the snowmelt in the Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 452-463页

作者： Xiang LI Peng CUI Xue-Qin zhang fang zhang Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of sciences Beijing 100049China China‒Pakistan Joint Research Center on Earth sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on ***,these connections are often overlooked,leading to an unclear relationship between temperature and *** study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme *** a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme *** annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow *** contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or *** direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt ***,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt *** also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt *** study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological *** findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关键词： Climate change Extreme temperature Snowmelt Structural equation model Tibetan Plateau

Winter-spring minimum temperature variations inferred from tree-ring δ^(13)C in southeastern China

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Journal of Forestry Research 2024年第5期35卷 182-190页

作者： Wenli Li Feifei Zhou Heng zhang Keyan fang Key Laboratory of Humid Subtropical Eco-Geographical Process(MOE) College of Geographic SciencesFujian Normal UniversityFuzhou 350007People’s Republic of China

Long-term temperature variations inferred from high-resolution proxies provide an important context to evaluate the intensity of current ***,tem-perature reconstructions in humid southeastern China are scarce and particularly lack long-term data,limiting us to obtain a complete picture of regional temperature *** this study,we present a well-verified reconstruction of winter-spring(January–April)minimum temperatures over southeastern China based on stable carbon isotopic(δ^(13)C)records of tree rings from Taxus wallichiana *** from 1860 to *** reconstruction accounted for 56.4%of the total observed *** periods occurred during the 1860s–1910s and 1960s–*** temperatures have had an upward trend since the 1920s,most of the cold extremes were in recent *** El Niño-Southern Oscillation(ENSO)variance acted as a key modulator of regional winter-spring minimum temperature ***,teleconnections between them were a nonlinear process,i.e.,a reduced or enhanced ENSO variance may result in a weakened or intensified temperature-ENSO relationship.

关键词： Tree rings Carbon isotope Southeastern China Extreme coldness El nino-southern oscillation

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Surface Topological Glycosylation-Mediated Mucoadhesion of Bacteria

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Chinese Journal of Chemistry 2024年第13期42卷 1447-1455页

作者： Xiao Kuang xiaobing Liu Ju Chen Wenyan Lv Mengmeng zhang Huan Chen Feng Wu Jinyao Liu School of life sciences Shanghai UniversityShanghai 200444China Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine Institute of Molecular MedicineState Key Laboratory of Systems Medicine for CancerRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and National Center for Translational MedicineShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234China

Sugar moieties present on bacterial surface serve as pivotal regulators of bacterial *** adjusting the abundance and distribution of surface sugar moieties can offer an important approach to manipulating bacterial behavior,but has been proven to be ***,surface topological glycosylation is reported to mediate the interaction of bacteria with mucous *** functionalized by sugar moieties with different branching are synthesized through iterative Michael addition and amide condensation *** a copper-catalyzed azide-alkyne cycloaddition,the resulting compounds with different branching structures can be attached onto bacterial surface that is modified with azido *** a proof-of-concept study,a set of topologically glycosylated probiotics(TGPs)is prepared using linear,two-branched,and tetra-branched compounds,*** interaction between mucin and TGPs was studied and the results demonstrate that,compared to unmodified bacteria,TGPs exhibit an enhanced adhesive capacity to mucin,which increases with the branching *** binding trend is observed in ex vivo colonic mucus adhesion experiments and bacteria glycosylated with tetra-branched compounds display the highest binding *** work proposes a chemical method to tune the abundance and distribution of sugar moieties on bacteria,providing unique significant insights into the manipulation of bacterial behavior through surface modification.

关键词： Topochemistry Bacteria Glycosylation Surface modification Mucoadhesion Click chemistry