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Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAL laser facility

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Matter and Radiation at Extremes 2024年第5期9卷 32-47页

作者： F.brun L.Ribotte G.boutoux X.Davoine P.E.Masson-Laborde Y.Sentoku n.Iwata n.blanchot D.batani I.Lantuéjoul L.Lecherbourg b.Rosse C.Rousseaux b.Vauzour D.Raffestin E.D’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CEA DAMCESTAF-33116 Le BarpFrance CEA DAMDIFF-91297 ArpajonFrance CEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine Laser(PETAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPECTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PETAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

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Advancements in assessing soil health through functional traits and energy flow analysis of soil

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Soil Ecology Letters 2024年第2期6卷 21-30页

作者： Jingnan Zhang Shiyu Li Elly Morrien neil b.McLaughlin Shixiu Zhang School of Life Sciences Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChineseAcademy of SciencesChangchun 130012China Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130012China Institute of biodiversity and Ecosystem Dynamics(IbED-ELD) Department of Ecosystem and Landscape DynamicsUniversity of AmsterdamScience Park 9041098 XHA msterdamThe Netherlands Ottawa Research and Development Centre Agriculture and Agri-Food CanadaOttawa K1AoC6Canada University of Chinese Academy of Sciences Bejing 100049China

We examined the development of soil nematodes ecological indices from the perspective off *** found that soil nematode energy flow analyses based on multiple functional traits quantify the dynamics of energy flow across multipletrophic levels to provide a more comprehensive *** conducted comparative analyses of the sensitivities of nMF and energy flow to verify that the energy flow analyses are more sensitive and have greater potential to reveal soil health and ecosystem *** in-depth studies of functional traits and energy flow analysis can help us achieve informed soil management practices,sustainable agriculture,*** Tess CT nematode ecological index based on functional traits:MI El,S,bI,C1 nMF bongen.1990 Ferrisetal,2001 Ferris,2010 energs low analysis of soil nematodes Compare thecological index(nMf)and bacterivores(ba)Functional traits Energy flux Fungihores(Fn)rahn Soilnematodes latitude Lindicator Plant-parasites(PP)PF Energflus Soilhealth Omnivores-predators(oP)latitude Energy flow analysis of soil nematodes:by quantifying energy fux among trophic groups barbes et al.,2014,2018 This paper examines the development of ecological indices for soil nematodes from the perspective of functional *** emphasizes the increasing significance of integrating multiple functional traits to achieve a more accurate assessment of soil *** indices based on life history strategies,feeding habits,and body size provide useful tools for assessing soil ***,these indices do not fully capture the dynamics ofenergyflow across multiple-trophic levels inthesoil foodweb,which is critical fora deeperunderstanding of the intrinsic properties of soil *** combining functional traits such as functional group,body size,feeding preference and metabolic rate,nematode energy flow analyses provide a more comprehensive *** approach establishes a direct correlation between changes

关键词： soil nematodes soil health nematodefoodweb functional traits energyflux

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Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser Science and Engineering 2024年第3期12卷 62-68页

作者： L.R.Yin X.F.Li Y.J.Gu n.Cao Q.Kong M.büscher S.M.Weng M.Chen Z.M.Sheng Key Laboratory of nuclear Physics and Ion-beam Application(MoE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SAnKEn(Institute of Scientific and Industrial Research) Osaka UniversityOsakaJapan Sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±bargmann±Michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan b.M.P.Singhakumara Xiangcheng Mi I.A.U.n.Gunatilleke C.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China botany Department University of PeradeniyaPeradeniyaSri Lanka

background:no studies have documented long-term trends in aboveground biomass(AGb)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGb for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).no differences exist among sites in AGb primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGb with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGb and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGb and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGb among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

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Contributions to the knowledge of Antarctodon sobrali(Mammalia:Astrapotheria)from the Eocene of Antarctica

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Advances in Polar Science 2024年第1期35卷 48-62页

作者： Javier n.GELFO Consejo nacional de Investigaciones Científicasy Técnicas(COnICET) Buenos Aires C1425FQBArgentina División Paleontología Vertebrados Museo de La PlataFacultad de Ciencias Naturales y Museo de La PlataUniversidad Nacional de La PlataLa Plata B1900FWAArgentina

The Astrapotheria constitutes one of the five orders of extinct South American native ungulates,with a fossil record that also extends to the Eocene of the Antarctic *** contrast to the abundant specimens known for litoptern Sparnotheriodontidae and metatherians,astrapotheres are represented by scant remains assigned to the endemic Antarctodon sobrali and indeterminate astrapotheres,restricted to levels 35C_(u0)and 35n of the Cucullaea I Allomember of the La Meseta *** discovery of alower molar assignable to this species in the Eocene levels of Seymour(Marambio)Island,enables a revision of the diagnosis and the homologies of the dental characters used to describe this taxon.A reanalysis of its phylogenetic relationships reveals the nearly simultaneous presence of basal astrapotheres in the early Eocene of Itaboraí(brazil),Patagonia,and West *** taxa are characterized by lacking dental specializations usually associated with more abrasive diets like terminal forms of Uruguaytheriinae and *** appears to have thrived on the Antarctic continent during the Early Eocene Climatic Optimum within the paleoclimatic context of a hot-house *** present conditions in Antarctica where no terrestrial mammals inhabit,the early Eocene climate was characterized by warmer temperatures and a biologically diverse environment rich in primary producers,dominated by nothofagus forests,encompassing both deciduous and evergreen forests,which supported a diverse assemblage of continental vertebrates.

关键词： Astrapotheria Antarctodon Eocene Seymour Island La Meseta Formation

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Sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop Science 2024年第3期9卷 160-169页

作者： n.M.Al-Ashkar b.A.bakry H.M.S.El-bassiouny M.M.S.Abdallah M.S.Sadak botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(nO)donor sodium nitroprusside(SnP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of SnP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of SnP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid Sodium nitroprusside Antioxidant enzymes Yield

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Academic productivity correlates with industry earnings in foot and ankle fellowship programs in the United States:A retrospective analysis

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World Journal of Orthopedics 2024年第2期15卷 129-138页

作者： Albert T Anastasio Anthony n baumann Kempland C Walley Kyle J Hitchman Conor O’neill Jonathan Kaplan Samuel b Adams Department of Orthopedic Surgery Duke University HospitalDurhamNC 27710United States College of Medicine Northeast Ohio Medical UniversityRootstownOH 44272United States Department of Orthopedic Surgery University of MichiganAnn ArborMI 48109United States School of Osteopathic Medicine Campbell UniversityLillingtonNC 27546United States

bACKGROUnD The study investigates the connection between academic productivity and industry earnings in foot and ankle orthopedic surgery *** metrics like the H-index and Open Payments Database(OPD)data,it addresses a gap in understanding the relationship between scholarly achievements and financial outcomes,providing a basis for further exploration in this specialized medical *** To elucidate the trends between academic productivity and industry earnings across foot and ankle orthopedic surgery fellowship programs in the United *** This study is a retrospective analysis of the relationship between academic productivity and industry earnings of foot and ankle orthopedic surgery fellowships at an individual faculty and fellowship *** productivity was defined via H-index and recorded from the Scopus *** earnings were recorded from the *** Forty-eight foot and ankle orthopedic surgery fellowships(100%of fellowships)in the United States with a combined total of 165 physicians(95.9%of physicians)were *** individual physician(n=165)total life-time earnings reported on the OPD website was United States Dollar(USD)451430.30±1851084.89(range:USD 25.16-21269249.85;median:USD 27839.80).Mean physician(n=165)H-index as reported on Scopus is 14.24±12.39(range:0-63;median:11).There was a significant but weak correlation between individual physician H-index and individual physician total life-time earnings(Pn’s rho=0.334)and a significant and moderate positive correlation between combined fellowship H-index and total life-time earnings per fellowship(P=0.004,Spearman’s rho=0.409).COnCLUSIOn There is a significant and positive correlation between academic productivity and industry earnings at foot and ankle orthopedic surgery fellowships in the United *** observation is true on an individual physician level as well as on a fellowship level.

关键词： Sunshine act Foot and ankle Orthopedic surgery Orthopedic fellowship Industry earnings

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A Learning-based Control Framework for Fast and Accurate Manipulation of a Flexible Object

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Journal of bionic Engineering 2024年第4期21卷 1761-1774页

作者： Junyi Wang Xiaofeng Xiong Silvia Tolu Stanislav n.Gorb Department of Electrical and Photonics Engineering Technical University of DenmarkAnker Engelunds Vej 101Kongens LyngbyZealand2800Denmark SDU biorobotics Mærsk Mc-Kinney Møller InstituteUniversity of Southern Denmark(SDU)Campusvej 55Odense MFunen5230Denmark Department Functional Morphology and biomechanics Zoological InstituteUniversity of KielAm Botanischen Garten 1–9D-24118KielSchleswig-HolsteinGermany

This paper presents a learning-based control framework for fast(3 times of others).besides,motion tracking errors are greatly reduced to 13.29 and 22.36 of constant impedance control by the OIAC of the proposed *** ad... 详细信息

This paper presents a learning-based control framework for fast(nd accurate manipulation of a flexible object,i.e.,whip *** framework consists of a motion planner learned or optimized by an algorithm,Online Impedance Adaptation Control(OIAC),a sim2real mechanism,and a visual feedback *** experimental results show that a soft actor-critic algorithm outperforms three Deep Reinforcement Learning(DRL),a nonlinear optimization,and a genetic algorithm in learning generalization of motion *** can greatly reduce average learning trials(tond maximize average rewards(to>3 times of others).besides,motion tracking errors are greatly reduced to 13.29 and 22.36 of constant impedance control by the OIAC of the proposed *** addition,the trajectory similarity between simulated and physical whips is *** presented framework provides a new method integrating data-driven and physics-based algorithms for controlling fast and accurate arm manipulation of a flexible object.

关键词： Deep reinforcement learning Deformable object manipulation Variable impedance control Sim2real Visual tracking

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Symmetry quantification and segmentation in STEM imaging through Zernike moments

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Chinese Physics b 2024年第8期33卷 39-48页

作者： Jiadong Dan Cheng Zhang 赵晓续 n.Duane Loh Department of biological Sciences National University of SingaporeSingapore Center for bioimaging Sciences(CbIS) National University of SingaporeSingapore Department of Physics National University of SingaporeSingapore School of Materials Science and Engineering Peking UniversityBeijing 100871China

We present a method using Zernike moments for quantifying rotational and reflectional symmetries in scanning transmission electron microscopy(STEM)images,aimed at improving structural analysis of materials at the atomic *** technique is effective against common imaging noises and is potentially suited for low-dose imaging and identifying quantum *** showcase its utility in the unsupervised segmentation of polytypes in a twisted bilayer TaS_(2),enabling accurate differentiation of structural phases and monitoring transitions caused by electron beam *** approach enhances the analysis of structural variations in crystalline materials,marking a notable advancement in the characterization of structures in materials science.

关键词： scanning transmission electron microscopy(STEM) symmetry segmentation

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Comparison of mismatch repair and immune checkpoint protein profile with histopathological parameters in pancreatic,periampullary/ampullary,and choledochal adenocarcinomas

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 875-882页

作者： Arzu Hazal Aydın nesrin Turhan Department of Pathology Aksaray University Aksaray Training and Research HospitalAksaray 68200Turkey Department of Pathology University of Health Sciences Ankara City HospitalAnkara 06800Turkey

bACKGROUnD Pancreatic,periampullary/ampullary,and choledochal adenocarcinomas are aggressive malignancies with a poor *** checkpoint blockade is a promising treatment option for several tumor types.H long terminal repeatassociating 2(HHLA2),which is analogous to programmed death-ligand 1(PDL1),is a recently discovered member of the b7/cluster of differentiation 28 family and is expressed in many *** To analyze the expression of HHLA2 and its association with the pathologic biomarkers that predict sensitivity to *** ninety-two adenocarcinoma cases located in the pancreas,ampulla,and distal common bile duct were *** study assessed 106 pancreaticoduodenectomy and distal/total pancreatectomy samples that were delivered to Ankara City Hospital between 2019 and *** was conducted to examine the expression of DnA mismatch repair(MMR),PD-L1,and HHLA2 *** Patients with high HHLA2 expression had a higher mean age than those with low *** HHLA2 expression was associated with high perineural ***2 expression was low in pathological stage T3(pT)3 cases and high in pathological stage T1,T2,and T4 *** was no correlation between HHLA2 expression and the expression of MMR proteins and *** Evaluation of HHLA2 expression in microsatellite stable and PD-L1-negative tumors may be useful for predicting the response of individuals to immunotherapy and may serve as a novel therapeutic target for immunotherapy in advanced-stage disease.

关键词： H long terminal repeat-associating 2 Programmed death-ligand 1 Adenocarcinoma Pancreas Ampulla of Vater Distal common bile duct

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