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Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： j.-R.Marquès L.Lancia P.Loiseau P.Forestier-Colleoni M.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli j.Domange F.Hannachi P.Nicolaï M.salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GsI Helmholtzzentrum für schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CsA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CsA.

关键词： acceleration hydrodynamic collision

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Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of structural and Civil Engineering 2024年第2期18卷 170-183页

作者： R.MOHANA s.M.Leela BHARATHI Department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 MPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

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Water Vapor Information from satellite and Its Applications

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Advances in Atmospheric sciences 2024年第1期41卷 188-189页

作者： B.j.sOHN school of Earth and Environmental sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

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Nonstationary laser-supported ionization wave in layer of porous substance with subcritical density

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Matter and Radiation at Extremes 2024年第1期9卷 58-70页

作者： s.Yu Gus’kov R.A.Yakhin P.N.Lebedev Physical Institute of Russian Academy of sciences Leninskii Prospect 53Moscow 119991Russia

A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced *** corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various *** solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore *** parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications.

关键词： laser pulse porous

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sCFD1 in amyotrophic lateral sclerosis: reconciling a genetic association with in vivo functional analysis

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Neural Regeneration Research 2024年第6期19卷 1201-1202页

作者： Ruben j.Cauchi Centre for Molecular Medicine and Biobanking Biomedical Sciences BuildingDepartment of Physiology and Biochemistry Faculty of Medicine and Surgery University of Malta

Amyotrophic lateral sclerosis(ALs) is a neurodegenerative disease characterized by progressive loss of upper and lower motor neurons,resulting in muscle weakness and spasticity,eventually leading to death due to respiratory *** by our group of a casecontrol cohort from an isolated island population have found that genetics plays a significant role in disease etiology(Farrugia Wismayer et al.,2023).

关键词： PROTEIN sLY1

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Enhancing Ulcerative Colitis Diagnosis:A Multi-Level Classification Approach with Deep Learning

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Computer Modeling in Engineering & sciences 2024年第7期140卷 1129-1142页

作者： Hasan j.Alyamani Department of Information systems Faculty of Computing and Information Technology in RabighKing Abdulaziz UniversityJeddah21589Saudi Arabia

The evaluation of disease severity through endoscopy is pivotal in managing patients with ulcerative colitis,a condition with significant clinical ***,endoscopic assessment is susceptible to inherent variations,both within and between observers,compromising the reliability of individual *** study addresses this challenge by harnessing deep learning to develop a robust model capable of discerning discrete levels of endoscopic disease *** initiate this endeavor,a multi-faceted approach is embarked *** dataset is meticulously preprocessed,enhancing the quality and discriminative features of the images through contrast limited adaptive histogram equalization(CLAHE).A diverse array of data augmentation techniques,encompassing various geometric transformations,is leveraged to fortify the dataset’s diversity and facilitate effective feature extraction.A fundamental aspect of the approach involves the strategic incorporation of transfer learning principles,harnessing a modified ResNet-50 *** augmentation,informed by domain expertise,contributed significantly to enhancing the model’s classification *** outcome of this research endeavor yielded a highly promising model,demonstrating an accuracy rate of 86.85%,coupled with a recall rate of 82.11%and a precision rate of 89.23%.

关键词： Ulcerative colitis deep learning CLAHE transfer learning geometric transformations

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4He monolayer on graphene: a quantum Monte Carlo study

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Communications in Theoretical Physics 2024年第9期76卷 151-159页

作者： s Yu M Boninsegni Department of Physics University of Alberta

We revisit the problem of adsorption of a single4He layer on graphene, focusing on the commensurate(C1/3) crystalline phase, specifically on whether it may possess a nonzero superfluid response, and on the existence of superfluid phases, either（metastable） liquid or vacancy-doped crystalline. We make use of canonical quantum Monte Carlo simulations at zero and finite temperature, based on a realistic microscopic model of the system. Our results confirm the absence of any superfluid response in the commensurate crystal, and that no thermodynamically stable uniform phase exists at lower coverage. No evidence of a possibly long-lived, metastable superfluid phase at C1/3coverage is found. Altogether, the results of ground-state projection methods and finite-temperature simulations are entirely consistent.

关键词： helium low-dimensional systems quantum Monte Carlo superfluidity supersolids

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Intelligent Machine Learning Based Brain Tumor segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Computers, Materials & Continua 2024年第4期79卷 1301-1317页

作者： sharaf j.Malebary Department of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a pressing public health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-prone task, necessitatingthe development of more precise and efficient methodologies. To address this formidable challenge, we proposean advanced approach for segmenting brain tumorMagnetic Resonance Imaging (MRI) images that harnesses theformidable capabilities of deep learning and convolutional neural networks (CNNs). While CNN-based methodshave displayed promise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shapes, varying sizes, uneven distribution, and limited available data, poses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a pioneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. Our proposed approachencompasses preprocessing steps that enhance image visualization, a customized layered U-Net model tailoredfor precise segmentation, and the inclusion of dropout layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exploit contextual information within brain tumorMRI images,resulting in a substantial enhancement in segmentation *** experimental results attest to the exceptionalperformance of our framework, with accuracy rates surpassing 97% across diverse datasets, showcasing therobustness and effectiveness of our approach. Furthermore, we conduct a comprehensive assessment of ourmethod’s capabilities by evaluating various performance measures, including the sensitivity, jaccard-index, andspecificity. Our proposed model achieved 99% accuracy. The implications of our findings are profound. Theproposed Hybrid U-Net model emerges as a highly promising diagnostic tool, poised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MRI images

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Making connections with cell surface auxin signaling

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Molecular Plant 2024年第4期17卷 522-524页

作者： Angus s.Murphy University of Maryland College ParkMDUSA

The discovery and characterization of the nuclear AUX-indole-3-acetic acid(IAA)-TIR1/AFB auxin co-receptor complex in the model plant Arabidopsis at the outset of the 21st century was a hallmark event in biological *** decades of subsequent discovery demonstrated the central role of the nuclear auxin perception mechanism in virtually every stage of Viridiplantae *** auxin receptors were also shown to be essential for later stages of differential hypocotyl,coleoptile,and root tropisms,but the most rapid responses were found to persist in Arabidopsis mutants lacking important components of the receptor mechanism(Napier,2021;Peer and Murphy,2022).In particular,rapid cellular elongation observed in tropic growth or after experimental application of auxin is mediated by H+extrusion across the plasma membrane(PM).The resulting apoplastic acidification activates extensin proteins that loosen cell walls to allow for turgor-driven cellular *** initial events occur in a time frame that precludes nuclear signaling and now can be clearly attributed to a cell surface auxin co-receptor complex and downstream signaling intermediaries.

关键词： Arabidopsis surface walls

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One-neutron stripping process in the^(209)Bi(^(6)Li,^(5)Li)^(210)Bi*reaction reaction

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Nuclear science and Techniques 2024年第6期35卷 120-129页

作者： Gao-Long Zhang Zhen-Wei jiao Guang-Xin Zhang E.N.Cardozo B.Paes shi-Peng Hu jian-Qiang Qian Daniele Mengoni Wei-Wei Qu Cong-Bo Li Yun Zheng Huan-Qiao Zhang Hui-Bin sun Nan Wang Chun-Lei Zhang j.j.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.Illana s.Bakes I.Zanon s.Aydin Gde Angelis M.siciliano R.Menegazzo s.M.Lenzi s.Akkoyun L.F.Canto j.Lubian school of Physics Beihang UniversityBeijing 100191China sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340 NiteróiRio de JaneiroBrazil Laboratorio TANDAR Comisión Nacional de Energía AtómicaBKNA1650 San MartíınArgentina Institute for Advanced study in Nuclear Energy and safety Shenzhen UniversityShenzhen 518060China shenzhen Key Laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPaduaItaly Dipartimento di fisica Astronomia dell’Universita di padova PaduaItaly state Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Laboratori Nazionali di Legnaro INFN35020 LegnaroItaly INFN Sezione di Napoli80126 NaplesItaly Dipartimento di Farmacia Universitàdi Napoli“Federico II”80131 NaplesItaly Department of Natural and Mathematical sciences Faculty of EngineeringTarsus University33480 MersinTurkey Physics Division Argonne National LaboratoryLemontILUSA Department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroRio de Janeiro CP 6852821941-972Brazil

One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy ***γ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross *** one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)*** calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.

关键词： Transfer reaction Weakly bound nuclei Cross section

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