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Photonics Research 2024年第5期12卷 1078-1092页

作者： RODRIGO MARTIN-HERNANdeZ LORENZ GRUNEWALD LUIS SANCHEZ-TEJERINA LUIS PLAJA ENRIQUECONEJERO JARQUE CARLOS HERNANdeZ-GARCIA SEBASTIAN MAI Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversidad de SalamancaE-37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaE-37008 SalamancaSpain Institute of Theoretical Chemistry Faculty of ChemistryUniversity of Vienna1090 ViennaAustria Vienna Doctoral School in Chemistry(DoSChem) Faculty of ChemistryUniversity of Vienna1090 ViennaAustria departamento de Electricidad y Electrónica Universidad de Valladolid47011 ValladolidSpain

*** *** thank Valentina Shumakova,Elizaveta Gangrskaia,Alessandra Bellissimo,Audrius Pugzlys,and Andrius Baltu?ka for fruitful discussions and computational support by the Vienna Scientific Cluster(VSC 4).The authors thankfully acknowledge the computer resources at MareNostrum and SCAYLE,and the technical support provided by Barcelona Supercomputing Center(RES-FI-2022-3-0041).R.M.-H.,L.S.-T.,L.P.,E.C.J.,and C.H.-*** funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant Agreement No.851201)and support from Ministerio de Ciencia e Innovación(PID2022-142340NB-I00,PID2019-106910GB-I00).This research was funded in whole or in part by the Austrian Science Fund(FWF)(10.55776/ZK91).For open access purposes,the author has applied a CC BY public copyright license to any author accepted manuscript version arising from this submission.

关键词： metallic polarized discussions

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban Diaz Edgar Leonardo salamanca-Medina Roberto Tomas departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Woody plant taxonomic,functional,and phylogenetic diversity decrease along elevational gradients in Andean tropical montane forests:Environmental filtering and arrival of temperate taxa

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Plant Diversity 2024年第4期46卷 491-501页

作者： Guillermo Bañares-de-Dios Manuel J.Macía Gabriel Arellano Íñigo Granzow-de la Cerda Julia Vega-álvarez Itziar Arnelas Carlos I.Espinosa Norma Salinas Luis Cayuela departamento de Biología y geología Física y Química InorgánicaUniversidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain departamento de Biología Área de BotánicaUniversidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Centro de Investigación en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autónoma de MadridCalle Darwin 2MadridES-28049Spain Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA Oikobit LLC ***AlbuquerqueNM87120USA Real Jardín Botánico–CSIC Plaza Murillo 2MadridES-28014Spain departamento de Biología Animal EcologíaParasitologíaEdafología y Química AgrícolaUniversidad de SalamancaCalle Donantes de Sangre s/nSalamancaES-37007Spain departamento de Biodiversidad Ecología y EvoluciónUniversidad Complutense de MadridCalle JoséAntonio Nováis 12Ciudad UniversitariaES-28040Spain departamento de Ciencias Biológicas y Agropecuarias Universidad Técnica Particular de LojaA.P.11-01-608 LojaEcuador Sección Química Pontificia Universidad Católica del PerúA.P.Lima 32LimaPeru ECI School of Geography and EnvironmentUniversity of OxfordOX13QYOxfordshireUnited Kingdom Instituto de Investigación en Cambio Global(IICG-URJC) Universidad Rey Juan CarlosCalle Tulipán s/nMóstolesMadridES-28933Spain

Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short *** research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients,but other facets should be *** first time,we simultaneously assessed elevational trends in taxonomic,functional,and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary *** investigation covered four transects(traversing ca.2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range(ca.10°).Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic,functional,and phylogenetic diversity as elevation increased,although the decrease was less pronounced for higher Hill *** exception was a slight increase in phylogenetic diversity when dominant species were *** decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands,where the increasingly harsher conditions exclude species and functional ***,the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional *** phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate *** could be explained by a decreasing presence and abundance of temperate,extratropical taxa towards the central Andes relative to northern or southern Andes,where they are more prevalent.

关键词： Altitudinal gradients Andes Environmentalﬁltering Out of the Tropical Lowlands Functional rarity Tropical Niche Conservatism

Premature losses of leaf area in response to drought and insect herbivory through a leaf lifespan gradient

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Journal of Forestry Research 2022年第1期33卷 39-50页

作者： Sonia Mediavilla Montserrat Martínez-Ortega Santiago Andrés Javier Bobo Alfonso Escudero departamento de Ecología Facultad de BiologíaUniversidad de Salamanca37071 SalamancaSpain departamento de Botánica y Fisiología Vegetal Facultad de BiologíaUniversidad de Salamanca37071 SalamancaSpain

Implications of the differences in leaf life span are still subject to debate in the field of *** leaf traits associated with these differences may be decisive for determining the distribution of tree species,this topic is particularly relevant in the context of climate *** study analyzes the effects of the differences in leaf life span on premature losses of leaf area owing to insect herbivory and to abiotic *** of leaf area may be an important determinant of total leaf carbon *** Mediterranean tree species,distributed on four sites with different climates were *** species exhibited strong differences in leaf life span and in leaf traits,especially leaf mass per unit *** leaf area losses were estimated in response to insect herbivory and summer drought over two *** results revealed that,despite having older leaf cohorts with more damage,species with longer leaf duration had lower area lost to herbivores and less damage due to accelerated senescence during the summer *** respect to the predicted increase in water stress,deciduous species are at a disadvantage due to their high premature loss of leaf area and thus loss of photosynthetic capacity.

关键词： Accelerated senescence Insect herbivory Leaf life span Leaf structural reinforcement Summer drought

All-optical nonlinear chiral ultrafast magnetization dynamics driven by circularly polarized magnetic fields

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High Power Laser Science and Engineering 2023年第6期11卷 154-161页

作者： Luis Sánchez-Tejerina Rodrigo Martín-Hernández Rocío Yanes Luis Plaja Luis López-Díaz Carlos Hernández-García Grupo de Investigación en Aplicaciones del Láser y Fotónica Departamento de Física AplicadaUniversidad de SalamancaSalamancaSpain Present address:departamento de Electricidad y Electrónica Universidad de ValladolidValladolidSpain departamento de Física Aplicada Universidad de SalamancaSalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaSalamancaSpain

Ultrafast laser pulses provide unique tools to manipulate magnetization dynamics at femtosecond timescales,where the interaction of the electric field usually dominates over the magnetic *** proposals using structured laser beams have demonstrated the possibility to produce regions where intense oscillating magnetic fields are isolated from the electric *** these conditions,we show that technologically feasible tesla-scale circularly polarized high-frequency magnetic fields induce purely precessional nonlinear magnetization *** fundamental result not only opens an avenue in the study of laser-induced ultrafast magnetization dynamics,but also sustains technological implications as a route to promote all-optical non-thermal magnetization dynamics both at shorter timescales-towards the subfemtosecond regime-and at THz frequencies.

关键词： chiral behavior nonlinear dynamics ultrafast dynamics

Bulk lateral shearing interferometry for spatiotemporal study of time-varying ultrashort optical vortices

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Photonics Research 2022年第4期10卷 922-931页

作者： Miguel Lopez-Ripa Inigo J.Sola Benjamin Alonso Grupo de Aplicaciones del Laser y Fotonica(ALF) Departamento de Fisica AplicadaUniversidad de Salamanca37008 SalamancaSpain

The spatiotemporal measurement of ultrashort laser beams usually involves techniques with complex set-ups or limited by instabilities that are unable to accurately retrieve the frequency-resolved wavefront. Here, we solve these drawbacks by implementing a simple, compact, and ultra-stable spatiotemporal characterization technique based on bulk lateral shearing spectral interferometry using a birefringent uniaxial crystal. We apply it to retrieve complex spatiotemporal structures by characterizing ultrafast optical vortices with constant and time-varying orbital angular momentum. This technique can operate in all the transparency range of the anisotropic elements,enabling the characterization in different spectral ranges like infrared, visible, or ultraviolet.

关键词： ultrashort shearing interferometry

NHC-catalysed[3+2]-asymmetric annulation between pyrazolin-4,5-diones and enals:synthesis of novel spirocyclic pyrazolone γ-butyrolactones and computational study of mechanism and stereoselectivity

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Organic Chemistry Frontiers 2022年第2期9卷 420-427页

作者： Marta Gil-Ordonez Alicia Maestro Pablo Ortega Pablo G.Jambrina Jose M.Andres GIR-SintACat-Instituto Universitario CINQUIMA y departamento de Química Orgánica Facultad de CienciasUniversidad de ValladolidPaseo Belén 747011 ValladolidSpain departamento de Química Física University of Salamanca37008 SalamancaSpain

Chiral pyrazolones with a spirocyclic centre at the C4-position are widely found in a large family of medically relevant *** recent years,organocatalysis,particularly that performed with quiral N-heterocyclic carbenes(NHCs),has allowed the enantioselective synthesis of these spirocyclic compounds despite its inherent *** this work,we describe the fully diastereo-and highly enantioselective synthesis of novel spirocyclic pyrazolone γ-butyrolactones via NHC-catalysed[3+2]annulation reaction of enals and 1H-pyrazol-4,*** understand the catalytic mechanism and origin of stereoselectivity,electronic structure calculations were carried *** considering various pathways,we concluded that the stereoselectivity-determining step is the formation of the lactone that proceeds after addition of the NHC derived homoenolate to the electrophilic carbonyl group of pyrazolin-4,*** calculations predict that the free energy barrier is lower for the(RS)product,which is also the main product experimentally obtained.

关键词： synthesis spiro mechanism

Coping with drought?Effects of extended drought conditions on soil invertebrate prey and diet selection by a fossorial amphisbaenian reptile

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Current Zoology 2023年第4期69卷 367-376页

作者： José Martín Jesús Ortega Roberto García-Roa Gonzalo Rodríguez-Ruiz Ana Pérez-Cembranos Valentín Pérez-Mellado departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain Institute of Evolutionary Biology CSIC-Universitat Pompeu FabraBarcelonaSpain Ethology Lab Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain departamento de Biología Animal Universidad de SalamancaSalamancaSpain

Arid climates are characterized by a summer drought period to which animals seem ***,in some years,the drought can extend for unusually longer *** the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought ***,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis *** data show interannual variations in summer drought *** abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer *** contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very ***,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had *** did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey ***,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with *** extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.

关键词： amphisbaenians drought feeding ecology soil invertebrates Trogonophis wiegmanni weather conditions

Scalable and low-cost fabrication of flexible WS_(2) photodetectors on polycarbonate

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npj Flexible Electronics 2022年第1期6卷 226-234页

作者： Jorge Quereda Sruthi Kuriakose Carmen Munuera Federico J.Mompean Abdullah M.Al-Enizi Ayman Nafady Enrique Diez Riccardo Frisenda Andres Castellanos-Gomez GISC Departamento de Física de MaterialesUniversidad Complutense de MadridMadridSpain Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMMCSIC)28049 MadridSpain department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Nanotechnology Group USAL–NanolabUniversidad de Salamanca37008 SalamancaSpain

We present a low-cost and easy-to-implement technique to fabricate large-area WS_(2) photodetector devices onto transparent and flexible polycarbonate *** method relies on the deposition of large-area(in the cm scale)thin films(~30 nm thick)of WS_(2) by a recently introduced abrasion-induced *** electrical contacts are then deposited by thermal evaporation through a shadow *** photodetectors present well-balanced performances with an good trade-off between responsivity(up to 144 mA/W at a source-drain voltage of 10 V and illumination power of 1μW)and response time(down to~70µs)and a detectivity value of 10^(8) *** found that the devices perform very reversibly upon several illumination and straining cycles and we found a moderate device-to-device variation.

关键词： drain illumination cost

Fourier-Limited Attosecond Pulse from High Harmonic GenerationAssistedbyUlitrafast MagneticFields

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Ultrafast Science 2023年第5期3卷 51-59页

作者： Rodrigo Martin-Hernandez Hongtao Hu Andrius Baltuska Luis Plaja Carlos Hernandez-Garcia'I Grupo de Investigacion en Aplicaciones del Lasery Fotonica Departamento de Fisica AplicadaUniversidad de SalamancaE-37008 SalamancaSpain Photonics Institute Technische Universitat WienA-1040 ViennaAustria

One of the main constraints for reducing the temporal duration of attosecond pulses is the attochirp inherent to the process of high-order harmonic generation(HHG).Though the attochirp can be compensated in the extreme-ultraviolet using dispersive materials,this is unfeasible toward x-rays,where the shortest attosecond or even sub-attosecond pulses could be *** theoretically demonstrate that HHG driven by a circularly polarized infrared pulse while assisted by an strong oscillating ultrafast intense magnetic field enables the generation of few-cycle Fourier-limited few attosecond *** such a novel scenario,the magnetic field transversally confines the ionized electron during the HHG process,analogously to a nanowire *** the electron is ionized,the transverse electron dynamics is excited by the magnetic field,acting as a high-energy reservoir to be released in the form of phase-locked spectrally wide high-frequency harmonic radiation during the electron recollision with the parent *** addition,the transverse breathing dynamics of the electron wavepacket,introduced by the magnetic trapping,strongly modulates the recollision efficiency of the electronic trajectories,thus the attosecond pulse *** aftermath is the possibility of producing high-frequency(hundreds of eV)attosecond isolated few-cycle pulses,almost Fourier *** isolated intense magnetic fields considered in our simulations,of tens of kT,can be produced in finite spatial volumes considering structured beams or stationary configurations of counter-propagating state-of-the-art multi-terawatt/petawatt lasers.

关键词： harmonic trapping intense