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free electron lasers driven by plasma accelerators:status and near-term prospects

High Power Laser Science and Engineering 2021年第4期9卷 112-126页

作者： C.Emma J.Van Tilborg R.Assmann S.Barber A.Cianchi S.Corde M.E.Couprie R.D'Arcy M.ferrario a.f.habib B.Hidding M.J.Hogan C.B.Schroeder A.Marinelli M.Labat R.Li J.Liu A.Loulergue J.Osterhoff A.R.Maier B.W.J.Mc Neil W.Wang SLAC National Accelerator Laboratory Menlo ParkCA 94025USA BELLA Center Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Deutsches Elektronen-Synchrotron DESY 22607 HamburgGermany INfN-LNf 00044 FrascatiItaly LOA ENSTA ParisCNRSEcole PolytechniqueInstitut Polytechnique de Paris91762 PalaiseauFrance Synchrotron SOLEIL L'Orme des MerisiersSaint-Aubin91192 Gif-sur-YvetteFrance Scottish Centre for the Application of Plasma-Based Accelerators SCAPA Department of PhysicsUniversity of StrathclydeScottish Universities Physics Alliance SUPAGlasgow G11XQUK Shanghai Institute of Optics and fine Mechanics Chinese Academy of SciencesShanghai 201800China Department of Physics University of StrathclydeScottish Universities Physics Alliance SUPAGlasgow G1IXQUK Cockcroft Institute Warrington WA44ADUK

Owing to their ultra-high accelerating gradients,combined with injection inside micrometer-scale accelerating wakefield buckets,plasma-based accelerators hold great potential to drive a new generation of free-electron lasers(fELs).Indeed,the first demonstration of plasma-driven fEL gain was reported recently,representing a major milestone for the *** groups around the world are pursuing these novel light sources,with methodology varying in the use of wakefield driver(laser-driven or beam-driven),plasma structure,phase-space manipulation,beamline design,and undulator technology,among *** paper presents our best attempt to provide a comprehensive overview of the global community efforts towards plasma-based fEL research and development.

关键词： plasma accelerators free electron lasers novel light sources

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Phylogenetic and morphometric relationships between two species of genus Auxis from the South China Sea and Java Sea

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Acta Oceanologica Sinica 2016年第10期35卷 76-82页

作者： habib Ahasan Environmental and Life Sciences Programme Faculty of ScienceUniversiti Brunei DarussalamJalan TungkuGadong BE 1410Brunei Darussalam Department of fisheries and Marine Science Noakhali Science and Technology UniversitySonapur-3814NoakhaliBangladesh Universiti Teknologi Brunei Jalan TungkuGadong BE 1410Brunei Darussalam

This study was aimed at examining the phylogenetic and morphometric relationship of frigate tuna（Auxis thazard） and bullet tuna（Auxis rochei） using mt DNA D-loop（control） region sequences and truss measurements,respectively. Maximum-likelihood（ML） tree and median-joining network showed that haplotypes from Auxis populations grouped separately. Discriminant function analyses and non-metric multidimensional scaling of morphometric data showed that bullet and frigate tuna were differed mainly with respect to truss measurements on the anterior region, suggesting adaptation to different diets available in different environments. Historic demographic analyses of sequence data showed that both bullet and frigate tuna had not undergone a significant sudden population expansion recently. Non-significant value of Tajimas＇ s D and fu＇s f_S were indicated an effective large and stable population size for longer period of both species in South China Sea and Java Sea species. This study gives first report on the complementary relationship between morphometric and genetic analysis in stock discrimination of genus Auxis.

关键词： phylogenetic relationship mtDNA D-loop morphometric analysis Auxis thazard Auxis rochei

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Structural analysis by Rietveld refinement of calcium and lanthanum phosphosilicate apatites

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Journal of Rare Earths 2013年第9期31卷 897-904页

作者： Hela Njema Khaled Boughzala habib Boughzala Khaled Bouzouita Laboratory of Industrial Chemistry National School of Engineering of Sfax Preparatory Institute for Engineering Studies of Monastir Laboratory of Materials and Crystallochemistry Preparatory Institute for Engineering Studies of Nabeul

Britholites with the general formula Ca10-xLnx（PO4）6-x（SiO4）xf2, （0≤x≤6） are considered to be promising matrices for the confinement of the by-products in the nuclear industry. A thermodynamic study showed that the stability of these compounds de-creased as the substitution rate increased. The present work was an attempt to gain more information about the structural changes in-duced by the substitution, in order to understand the observed stability decrease. The samples were successfully synthesized as a sin-gle-phase apatite by a solid-state reaction between 1200 and 1400 °C. The structural refinement indicated that the La3＋ions preferen-tially occupied the 6（h） sites. A progressive shift of f-along the c-axis outside its ideal position occurred as a result of the substitution increase. This might be the cause of the observed stability decrease, especially as the energies of the La-O, La-f and Si-O bonds are higher than those of Ca-O, Ca-f and P-O. The distribution of La3＋ between the two non-equivalent sites was confirmed by the charge distribution method.

关键词： britholites Rietveld refinement infrared spectroscopy charge distribution method rare earths

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Transfer learning from T1-weighted to T2-weighted Magnetic resonance sequences for brain image segmentation

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 26-39页

作者： Imene Mecheter Maysam Abbod habib Zaidi Abbes Amira Brunel University LondonUK Geneva University Hospital GenevaSwitzerland Geneva University GenevaSwitzerland University of Groningen GroningenNetherlands University of Southern Denmark OdenseDenmark University of Sharjah SharjahUAE De Montfort University LeicesterUK

Magnetic resonance(MR)imaging is a widely employed medical imaging technique that produces detailed anatomical images of the human *** segmentation of MR im-ages plays a crucial role in medical image analysis,as it enables accurate diagnosis,treatment planning,and monitoring of various diseases and *** to the lack of sufficient medical images,it is challenging to achieve an accurate segmentation,especially with the application of deep learning *** aim of this work is to study transfer learning from T1-weighted(T1-w)to T2-weighted(T2-w)MR sequences to enhance bone segmentation with minimal required computation *** the use of an excitation-based convolutional neural networks,four transfer learning mechanisms are proposed:transfer learning without fine tuning,open fine tuning,conservative fine tuning,and hybrid transfer ***,a multi-parametric segmentation model is proposed using T2-w MR as an intensity-based augmentation *** novelty of this work emerges in the hybrid transfer learning approach that overcomes the overfitting issue and preserves the features of both modalities with minimal computation time and *** segmentation results are evaluated using 14 clinical 3D brain MR and CT *** results reveal that hybrid transfer learning is superior for bone segmentation in terms of performance and computation time with DSCs of 0.5393±*** T2-w-based augmentation has no significant impact on the performance of T1-w MR segmentation,it helps in improving T2-w MR segmentation and developing a multi-sequences segmentation model.

关键词： computer vision convolution image segmentation learning(artificial intelligence)

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Approximate Boundary Conditions for Patch Antennas Mounted on Thin Dielectric Layers

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Communications in Computational Physics 2006年第6期1卷 1076-1095页

作者： habib Ammari Hyeonbae Kang Eunjoo Kim Centre de Math´ematiques Appliqu´ees CNRS UMR 7641 and Ecole Polytechnique91128 Palaiseau CedexFrance Department of Mathematical Sciences and RIM Seoul National UniversitySeoul 151-747Korea

In this paper we discuss scattering problems inherent in curved microstrip structures mounted on thin dielectric *** provide approximate boundary conditions for such structures in the framework of integral equations.

关键词： Approximate boundary conditions boundary integral method thin dielectric layer patch antenna

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Existence and Global Asymptotic Behavior of Positive Solutions for Sublinear and Superlinear fractional Boundary Value Problems

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 1-28页

作者： Imed BACHAR habib MAAGLI faten TOUMI Zagharide ZINE EL ABIDINE Mathematics Department College of Science King Saud University P.O.Box 2455 Riyadh 11451 Saudi Arabia. Department of Mathematics College of Sciences and Arts Rabigh Campus King Abdulaz University P.O.Box 344 Rabigh 21911 Saudi Arabia. Departement de Mathematiques Faculte des Sciences de Tunis Campus Universitalre 2092 Tunis Tunisia.

In this paper, the authors aim at proving two existence results of fractional differential boundary value problems of the form （Pa,bα）{D^au（x）＋f（x,u（x））=0,x∈（0,1）,u（0）=u（1）=0,D^a-3u（0）=a,u^（1）=-6where 3 ≤ a 〈 4, D^ is the standard Riemann-Liouville fractional derivative and a, b are nonnegative constants. first the authors suppose that f（x, t） = -p（x）t^σ, with cr ~ （-1, 1） and p being a nonnegative continuous function that may be singular at x - 0 or x - 1 and satisfies some conditions related to the Karamata regular variation theory. Combining sharp estimates on some potential functions and the Sch^uder fixed point theorem, the authors prove the existence of a unique positive continuous solution to problem （P0,0）. Global estimates on such a solution are also obtained. To state the second existence result, the authors assume that a, b are nonnegative constants such that a ＋ b 〉 0 and f（x, t） -= tφ（x, t）, with φ（x, t） being a nonnegative continuous function in （0, 1） × [0, ∞） that is required to satisfy some suitable integrability condition. Using estimates on the Green＇s function and a perturbation argument, the authors prove the existence and uniqueness of a positive continuous solution u to problem （Pa,b）, which behaves like the unique solution of the homogeneous problem corresponding the existence results. to （Pa,b）. Some examples are given to illustrate the existence results.,

关键词： fractional differential equation Positive solution fractional Green's function Karamata function Perturbation arguments Sch/iuder fixad point theorem

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Metals and metalloid bioconcentrations in the tissues of Typha latifolia grown in the four interconnected ponds of a domestic landfill site

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Journal of Environmental Sciences 2017年第4期29卷 56-68页

作者： Zohra Ben Salem Xavier Laffray Ahmed Al-Ashoor habib Ayadi Lotfi Aleya Bourgogne franche-Comte University Chrono-Environnement Laboratory UMR CNRS 6249 F-25030 Besancon Cedex France Paris Est-Creteil University IPE team iEES Paris UMR 7618 F-94010 Creteil Cedex Prance Thi Qar University IQ-64001 AI Nasiriyah Iraq Sfax University LR/UR/05ES05 Biodiversity and Aquatic Ecosystem BP 1171 CP 3000 Sfax Tunisia

The uptake of metals in roots and their transfer to rhizomes and above-ground plant parts（stems, leaves） of cattails（Typha latifolia L.） were studied in leachates from a domestic landfill site（Etueffont, france） and treated in a natural lagooning system. Plant parts and corresponding water and sediment samples were taken at the inflow and outflow points of the four ponds at the beginning and at the end of the growing season. Concentrations of As, Cd, Cr, Cu, fe, Mn, Ni and Zn in the different compartments were estimated and their removal efficiency assessed, reaching more than 90% for fe, Mn and Ni in spring and fall as well in the water compartment. The above-and below-ground cattail biomass varied from 0.21 to 0.85, and 0.34 to 1.24 kg dry weight/m^2, respectively, the highest values being recorded in the fourth pond in spring 2011. The root system was the first site of accumulation before the rhizome, stem and leaves. The highest metal concentration was observed in roots from cattails growing at the inflow of the system＇s first pond. The trend in the average trace element concentrations in the cattail plant organs can generally be expressed as： fe 〉 Mn 〉 As 〉 Zn 〉 Cr 〉 Cu 〉 Ni 〉 Cd for both spring and fall. While T. latifolia removes trace elements efficiently from landfill leachates, attention should also be paid to the negative effects of these elements on plant growth.

关键词： Landfill leachate Lagooning Trace elements Typha latifolia Phytoremediation

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Howl variation across Himalayan, North African, Indian, and Holarctic wolf clades： tracing divergence in the world＇s oldest wolf lineages using acoustics

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Current Zoology 2017年第3期63卷 341-348页

作者： Lauren HENNELLY Bilal habib Holly ROOT-GUTTERIDGE Vicente PALACIOS Daniela PASSILONGO Department of Animal Ecology and Conservation Biology Wildlife Institute of India Dehradun India Department of Biology Syracuse University New York 13210 USA Cavanilles Institute for Biodiversity and Evolutionary Biology University of Valencia Avenue de Blasce Ibanez Valencia 46010 Spain Ricerca sulla Selvaggina e sui Miglioramenti Ambientali a fini faunistici (C.I.R.Se.M.A.E) Piazzale delle Cascine 18 Firenze 1-50144 Italy

Vocal divergence within species often corresponds to morphological, environmental, and genetic differences between populations. Wolf howls are long-range signals that encode individual, group, and subspecies differences, yet the factors that may drive this variation are poorly understood. furthermore, the taxonomic division within the Canis genus remains contended and additional data are required to clarify the position of the Himalayan, North African, and Indian wolves within Canis lupus. We recorded 451 howls from the 3 most basal wolf lineages-Himalayan C. lupus chanco-Himalayan haplotype, North African C. lupus lupaster, and Indian C. lupus pallipes wolves-and present a howl acoustic description within each clade. With an additional 619 howls from 7 Holarctic subspecies, we used a random forest classifier and principal component analysis on 9 acoustic parameters to assess whether Himalayan, North African, and Indian wolf howls ex- hibit acoustic differences compared to each other and Holarctic wolf howls. Generally, both the North African and Indian wolf howls exhibited high mean fundamental frequency （f0） and short duration compared to the Holarctic clade. In contrast, the Himalayan wolf howls typically had lower mean f0, unmodulated frequencies, and short howls compared to Holarctic wolf howls. The Himalayan and North African wolves had the most acoustically distinct howls and differed significantly from each other and to the Holarctic wolves. Along with the influence of body size and environmental differences, these results suggest that genetic divergence and/or geographic distance may play an important role in understanding howl variation across subspecies.

关键词： acoustic variation Canis lupus geographic variation mammal communication.

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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri f.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,france)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of feⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

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Tectonic Imprints of the Hazara Kashmir Syntaxis on the Mesozoic Rocks Exposed in Munda, Mohmand Agency, Northwest Pakistan

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Acta Geologica Sinica(English Edition) 2016年第2期90卷 440-455页

作者： Asghar ALI Umer habib Atta Ur REHMAN Noor ZADA Zain Ul ABIDIN Muhammad ISMAIL Department of Geology University of Peshawar

Two well-developed mesoscopic folds, D_2 and D_3, which postdate the middle amphibolite metamorphism, were recognized in the western hinterland zone of Pakistan. NW–SE trending D_2 folds developed during NE–SW horizontal bulk shortening followed by NE–SW trending D_3 folds, which developed during SE–NW shortening. Micro- to mesoscopically the NW–SE trending S2 crenulation cleavage, boudins and mineral stretching lineations are overprinted by D_3. The newly established NW–SE trending micro- to mesoscopic structures in Munda termed D_2, which postdated f_1/f_2, is synchronously developed with f3 structures in the western hinterland zone of Pakistan. We interpret that D2 and D3 folds are counterclockwise rotated in the tectonic event that has evolved the Hazara Kashmir Syntaxis after the main phase Indian plate and Kohistan Island Arc collision. Chlorite replacement by biotite in the main matrix crenulation cleavages indicates prograde metamorphism related with D2. The inclusion of muscovite and biotite in garnet porphyroblasts and the presence of staurolite in these rocks indicate that the Barrovian metamorphic conditions predate D2 and D3. We interpret that garnet, staurolite and calcite porphyroblasts grew before D2 because the well developed S2 crenulation cleavage wraps around these porphyroblasts.

关键词： western hinterland zone Hazara Kashmir Syntaxis mesostructures microstructures metamorphism tectonics

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