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Comparison of a Spectral Bin and Two Multi-Moment Bulk Microphysics Schemes for Supercell Simulation:Investigation into Key processes responsible for Hydrometeor Distributions and precipitation

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Advances in Atmospheric Sciences 2024年第5期41卷 784-800页

作者： marcus JOHNSON Ming XUE Youngsun JUNG Center for Analysis and prediction of Storms University of OklahomaNormanOK 73072USA School of Meteorology University of OklahomaNormanOK 73072USA Office of Science and Technology Integration National Weather ServiceSilver SpringMD 20910USA

There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(Mp)schemes because of their complicated geometries and physical *** supercell simulations are produced using the WrF model coupled with“full”Hebrew University spectral bin Mp(HU-SBM),and NSSL and Thompson bulk Mp(BMp)***-SBM downdrafts are typically weaker than those of the NSSL and Thompson simulations,accompanied by less rain ***-SBM produces more cloud ice(plates),graupel,and hail than the BMps,yet precipitates less at the *** limiting mass bins(and subsequently,particle size)of rimed ice in HU-SBM and slower rimed ice fall speeds lead to smaller melting-level net rimed ice fluxes than those of the *** from plates in HU-SBM,together with snow–graupel collisions,leads to a greater snow contribution to rain than those of the *** HU-SBM’s fall speeds using the formulations of the BMps after aggregating the discrete bin values to mass mixing ratios and total number concentrations increases net rain and rimed ice ***,they are smaller in magnitude than bulk rain,NSSL hail,and Thompson graupel net fluxes near the ***,the melting-layer net rimed ice fluxes are reduced when the fall speeds for the NSSL and Thompson simulations are calculated using HU-SBM fall speed formulations after discretizing the bulk particle size distributions(pSDs)into spectral *** results highlight precipitation sensitivity to storm dynamics,fall speed,hydrometeor evolution governed by process rates,and Mp pSD design.

关键词： precipitation spectral bin microphysics bulk microphysics parameterization microphysics processes WrF model supercell storm

A simple method for pulse contrast enhancement via self-focusing

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High power Laser Science and Engineering 2024年第2期12卷 51-61页

作者： Zaharit refaeli Gilad marcus Yariv Shamir Applied physics Division Soreq NRCYavneIsrael Applied physics Institute The Hebrew UniversityThe Edmond J.Safra Campus-Givat RamJerusalemIsrael

Here we report on a simple-to-implement and cost-effective approach for laser pulse contrast enhancement,based on the χ(3)nonlinear self-focusing *** intentionally induced and gently controlled self-focusing in a thin glass transforms the time-dependent intensity into variation in beam *** by a spatial discriminating filter,only the strongly focused fraction traverses the setup,at the expense of efficiency.A numerical model,accounting for the pulse and material parameters via a Gaussian ABCD matrix,provides an estimate for the instantaneous beam waist and transmission efficiency,which enables us to evaluate the resulting contrast *** estimated contrast enhancement spans between 0.5 and 2.5 orders of magnitude,in conjunction with approximately 25%–90%estimated efficiency,depending on the pulse *** a preliminary experiment we demonstrated the effect with 10s-μJ sub GW regime with approximately 40%efficiency and a contrast improvement of more than or equal to 20 dB.

关键词： nonlinear optics pulse contrast self-focusing ultrafast laser

Feature extraction for machine learning-based intrusion detection in IoT networks

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Digital Communications and Networks 2024年第1期10卷 205-216页

作者： Mohanad Sarhan Siamak Layeghy Nour Moustafa marcus Gallagher Marius portmann University of Queensland BrisbaneQLD4072Australia University of New South Wales CanberraACT2612Australia

A large number of network security breaches in IoT networks have demonstrated the unreliability of current Network Intrusion Detection Systems(NIDSs).Consequently,network interruptions and loss of sensitive data have occurred,which led to an active research area for improving NIDS *** an analysis of related works,it was observed that most researchers aim to obtain better classification results by using a set of untried combinations of Feature reduction(Fr)and Machine Learning(ML)techniques on NIDS ***,these datasets are different in feature sets,attack types,and network ***,this paper aims to discover whether these techniques can be generalised across various *** ML models are utilised:a Deep Feed Forward(DFF),Convolutional Neural Network(CNN),recurrent Neural Network(rNN),Decision Tree(DT),Logistic regression(Lr),and Naive Bayes(NB).The accuracy of three Feature Extraction(FE)algorithms is detected;principal Component Analysis(pCA),Auto-encoder(AE),and Linear Discriminant Analysis(LDA),are evaluated using three benchmark datasets:UNSW-NB15,ToN-IoT and *** pCA and AE algorithms have been widely used,the determination of their optimal number of extracted dimensions has been *** results indicate that no clear FE method or ML model can achieve the best scores for all *** optimal number of extracted dimensions has been identified for each dataset,and LDA degrades the performance of the ML models on two *** variance is used to analyse the extracted dimensions of LDA and ***,this paper concludes that the choice of datasets significantly alters the performance of the applied *** believe that a universal(benchmark)feature set is needed to facilitate further advancement and progress of research in this field.

关键词： Feature extraction Machine learning Network intrusion detection system IoT

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine Zanna Antoine Seyeux philippe marcus Jolanta´Swiatowska Chimie parisTech-CNrS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HEr)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution

Insights into the hydrogen evolution reaction in vanadium redox flow batteries:A synchrotron radiation based X-ray imaging study

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Journal of Energy Chemistry 2024年第4期91卷 132-144页

作者： Kerstin Köble Alexey Ershov Kangjun Duan Monja Schilling Alexander rampf Angelica Cecilia TomášFaragó marcus Zuber Tilo Baumbach roswitha Zeis Helmholtz Institute Ulm Karlsruhe Institute of Technology89081 UlmGermany Laboratory for Applications of Synchrotron radiation Karlsruhe Institute of Technology76131 KarlsruheGermany Institute for photon Science and Synchrotron radiation Karlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Department of Electrical Electronicsand Communication EngineeringFaculty of EngineeringFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)91058 ErlangenGermany Department of Mechanical and Industrial Engineering University of TorontoToronto M5S 3G8OntarioCanada

The parasitic hydrogen evolution reaction(HEr)in the negative half-cell of vanadium redox flow batteries(VrFBs)causes severe efficiency ***,a deeper understanding of this process and the accompanying bubble formation is *** benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray *** large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HEr activity in *** study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V *** hydrogen electrode(rHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt ***,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon *** detected areas with high HEr activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HEr-related performance *** described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.

关键词： Vanadium redox flow battery Synchrotron X-ray imaging Tomography Hydrogen evolution reaction Gas bubbles Deep learning

发现有血流动力学意义的冠状动脉狭窄:动态CT心肌灌注成像有额外诊断价值

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国际医学放射学杂志 2011年第6期 577-578页

作者： F.Bamberg A.Becker F.Schwarz r.p.marcus M.Greif F.V.Ziegler 王霁朏 Departments of Clinical radiology Ludwig-Maximilians UniversityKlinikum GrosshadernMarchioninistrasse 1581377 MunichGermany

目的探讨动态CT心肌灌注成像发现有血流动力学意义的冠状动脉狭窄的可行性,冠状动脉狭窄的血流动力学改变用血流储备分数(fractional flow reserve,FFr)来定义。材料与方法该研究经伦理委员会批准,并获得病人知情同意

关键词：心肌灌注成像血流动力冠状动脉狭窄 CT

全身MrI对糖尿病病人发生心脑血管疾病的远期预测价值

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国际医学放射学杂志 2014年第1期 74-75页

作者： F.Bamberg K.G.parhofer E.Lochner r.p.marcus D.Theisen H.M.Findeisen 王亚 Department of Clinical radiology Ludwig Maximilians University Klinikum Grosshadern Marchioninistrasse 15 81377 Munich Germany

目的研究全身MrI对一组糖尿病(DM)病人发生心脑血管疾病的预测价值。方法本研究符合HIpAA,经伦理委员会批准,均签署知情同意书。作者通过电话随访了65例

关键词：全身病人 DM 心脑血管疾病 MrI

Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai ren Li-Chao Qian Ying-Ying Cao marcus J Daniels Li-Na Song Ying Tian Zhong-Qiu Wang Department of radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of radiology NYU Langone HealthNew YorkNY 10016United States

BACKGrOUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(pDAC)is that most patients are usually diagnosed at late *** is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect pDAC at its earliest *** A total of 71 patients with pathologically proved pDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the *** staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging *** features were extracted from the region of interest(rOI)for each patient using Analysis Kit *** most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MrMr)*** forest(rF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the *** A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the rOI for each patient using Analysis Kit *** most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MrMr *** method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive *** radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built *** The radiomics model based on CT could serve as a promising non-invasive method in differential diag

关键词： pancreatic ductal adenocarcinoma radiomics Computed tomography American Joint Committee on Cancer staging

The global regulation of c-di-GMp and cAMp in bacteria

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mLife 2024年第1期3卷 42-56页

作者： Cong Liu rui Shi marcus S.Jensen Jingrong Zhu Jiawen Liu Xiaobo Liu Di Sun Weijie Liu Jiangsu Key Laboratory of phylogenomics&Comparative Genomics School of Life SciencesJiangsu Normal UniversityXuzhouChina Key Laboratory of Metabolic Engineering and Biosynthesis Technology Ministry of Industry and Information TechnologyNanjing University of Science and TechnologyNanjingChina

Nucleotide second messengers are highly versatile signaling molecules that regulate a variety of key biological processes in *** best-studied examples are cyclic AMp(cAMp)and bis-(3'-5')-cyclic dimeric guanosine monophosphate(c-di-GMp),which both act as global *** regulatory frameworks of c-di-GMp and cAMp in bacteria show several parallels but also significant *** this review,we llustrate the global regulatory models of the two nucleotide second messengers,compare the different regulatory frameworks between c-di-GMp and cAMp,and discuss the mechanisms and physiological significance of cross-regulation between c-di-GMp and cAMp.c-di-GMp responds to numerous signals de-pendent on a great number of metabolic enzymes,and it regulates various signal transduction pathways through its huge number of effectors with varying *** contrast,due to the limited quantity,the cAMp metabolic enzymes and its major effector are regulated at different levels by diverse *** performs its global regulatory function primarily by controlling the transcription of a large number of genes via cAMp receptor protein(Crp)in most *** review can help us understand how bacteria use the two typical nucleotide second messengers to effectively coordinate and integrate various physiological processes,providing theoretical guidelines for future research.

关键词： bacteria cAMp c-di-GMp cross-regulation Crp