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Controlled transition to different proton acceleration regimes:Near-critical-density plasmas driven by circularly polarized few-cycle pulses

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Matter and Radiation at Extremes 2023年第5期8卷 1-18页

作者： Shivani Choudhary De marco Sudipta Mondal Daniele Margarone Subhendu Kahaly AFFiLiATiONS 1 ELi-ALPS ELI-HU Non-Profit Ltd.Wolfgang Sandner utca 3Szeged 6728Hungary ELi Beamlines Center Institute of PhysicsCzech Academy of SciencesZa Radnicí835252-41 DolníBrezanyCzech Republic institute of Physics University of SzegedDóm tér 9H-6720 SzegedHungary

A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of *** on numerical simulations conducted over a wide range of experimentally achievable parameter space,reported here is a comprehensive investigation of the different facets of ion acceleration by relativistically intense circularly polarized laser pulses interacting with thin near-critical-density plasma *** results show that the plasma thickness,exponential density gradient,and laser frequency chirp can be controlled to switch the interaction from the transparent operating regime to the opaque one,thereby enabling the choice of a Maxwellian-like ion energy distribution with a cutoff energy in the relativistically transparent regime or a quasi-monoenergetic spectrum in the opaque ***,it is established that a multispecies target configuration can be used effectively for optimal generation of quasi-monoenergetic ion bunches of a desired ***,the feasibility is demonstrated for generating monoenergetic proton beams with energy peak atℰ≈20–40 MeV and a narrow energy spread ofΔℰ/ℰ≈18%–28.6%confined within a divergence angle of∼175 mrad at a reasonable laser peak intensity of i0≃5.4×10^(20)W/cm^(2).

关键词： acceleration regime circular

Protective benefit of minimally invasive liver surgery for hepatocellular carcinoma prior to transplant

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Hepatoma Research 2022年第1期8卷 179-187页

作者： Simone Khouzam Duilio Pagano marco Barbara Vito Di marco Giada Pietrosi marco Maringhini marco Canzonieri Sergio Calamia Salvatore Gruttadauria Sidney Kimmel Medical College Thomas Jefferson UniversityPhiladelphiaPA 19107USA Department for the Treatment and Study of Abdominal Diseases and Abdominal Transplantation IRCCS-ISMETT(Istituto di Ricovero e Cura a Carattere Scientifico-Istituto Mediterraneo per I Trapianti e Terapie ad Alta Specializzazione)UPMC(University of Pittsburgh Medical Center)via E.Tricomi 5Palermo 90127Italy Sezione di Gastroenterologia e Epatologia Dipartimento Biomedico di Medicina Interna e SpecialisticaUniversity of PalermoPalermo 90128Italy Medicina interna Universitàdi Palermo/ISMETTVia del Vespro 129Palermo 90127Italy Department of Surgery and Medical and Surgical Specialties University of CataniaCatania 95124Italy

Aim:The purpose of this study is to assess the benefit of laparoscopic liver resection(LLR)for hepatocellular carcinoma(HCC)given recurrence and future need for liver transplantation(LT).Methods:Data on liver resections were gathered from the istituto di Ricovero e Cura a Carattere Scientifico-istituto Mediterraneo per i Trapianti e Terapie ad alta specializzazione(iRCCS-iSMETT)from 2003-2021.A retrospective analysis of 1408 consecutive adult patients who had a liver resection was performed with categorization based on the underlying disease process.A sub-analysis studied the 291 patients who had an LLR with an intention to transplant approach after ***:From 2012 to 2020,iSMETT’s mean annual LLR rate was 45%.Data suggests that a laparoscopic approach to iterative surgical treatment for HCC has demonstrated protective *** to open surgery or LT,LLR is protective against the risk of de-listing,post-transplant patient death,tumor recurrence,adhesions,and bleeding in a cirrhotic *** Meier’s analysis showed no difference between post-LT survival curves for those with prior open abdominal surgery or LLR(P=0.658).Conclusion:Laparoscopic surgery has important protective advantages over laparotomy surgery for the surgical treatment of HCC,particularly since treatment is not always *** can be considered a bridge therapy for transplantation,ensuring less crowding of waiting lists,a desirable condition in areas of donor storage.

关键词： Laparoscopic liver resection hepatocellular carcinoma minimally invasive liver surgery

Non-locality and collective emission in disordered lasing resonators

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Light(Science & Applications) 2013年第1期2卷 79-84页

作者： marco Leonetti Claudio Conti Cefe Lopez iSC-CNR UOS Sapienza00185 RomaItaly institute for Material Science Madrid(iCMM-CSiC) 28049 MadridSpain Department of Physics University SapienzaI-00185 RomaItaly

Random lasing is observed in optically active resonators in the presence of *** the optical cavities involved are open,the modes are coupled,and energy may pour from one state to another provided that they are spatially *** the electromagnetic modes are spatially localized,our system may be actively switched to a collective state,presenting a novel form of non-locality revealed by a high degree of spectral correlation between the light emissions collected at distant *** a nutshell,light may be stored in a disordered nonlinear structure in different fashions that strongly differ in their spatial *** effect is experimentally demonstrated and theoretically explained in titania clusters embedded in a dye,and it provides clear evidence of a transition to a multimodal collective emission involving the entire spatial extent of the disordered *** results can be used to develop a novel type of miniaturized,actively controlled all-optical chip.

关键词： collective emission disorder nanophotonics random lasing

Quantitative Electrophilicity Measures

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物理化学学报 2018年第6期34卷 662-674页

作者： GONZáLEZ marco Martínez CáRDENAS Carlos RODRíGUEZ Juan i. LiU Shubin HEiDAR-ZADEH Farnaz MiRANDA-QUiNTANA Ramón Alain AYERS Paul W. Laboratory of Computational and Theoretical Chemistry Faculty of Chemistry University of Havana Havana 10400 Cuba. Departamento de Quimica and Centro de Quimica Universidade de Coimbra 3004-535 Coimbra Portugal. Departamento de Fisica Fac

Quantitative correlation of several theoretical electrophilicity measures over different families of organic compounds are examined relative to the experimental values of Mayr et ***,the ability to predict these values accurately will help to elucidate the reactivity and selectivity trends observed in charge-transfer reactions.A crucial advantage of this theoretical approach is that itprovides this information without the need of experiments,which are often demanding and ***,two different types of electrophilicity measures were ***,models derived from conceptual density functional theory(c-DFT),including Parr's original proposal and further generalizations of this index,are *** instance,the approaches of Gázquez et *** Chamorro et *** considered,whereby it is possible to distinguish between processes in which a molecule gains or loses ***,we also explored two novel electrophilicity *** one hand,the potential of environmental perturbations to affect electron incorporation into a system is analyzed in terms of recent developments in *** studies highlight the importance of considering the molecular surroundings when a consistent description of chemical reactivity is *** the other hand,we test a new definition of electrophilicity that is free from inconsistencies(so-called thermodynamic electrophilicity).This approach is based on Parr's pioneering insights,though it corrects issues present in the standard working expression for the calculation of ***,we use machine-learning tools(i.e.,symbolic regression) to identify the models that best fit the experimental *** this way,the best possible description of the electrophilicity values in terms of different electronic structure quantities is ***,this straightforward approach enables one to obtain good correlations between the theoretical and experimental quantities by using the simple,yet p

关键词： Electrophilicity Conceptual density functional theory Symbolic regression Genetic programming Grammatical evolution

Testing and numerical simulation of a medium strength rock material under unconfined compression loading

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 197-211页

作者： Aria Mardalizad Riccardo Scazzosi Andrea Manes marco Giglio Politecnico di Milano Department of Mechanical Engineering

This study aims to numerically and experimentally investigate the response of a medium strength rock material under unconfined compression loading up to failure. The unconfined compressive strength(UCS) is one of the most important parameters in characterising rock material behaviour. Hence the UCS is crucial in understanding the failure mechanism of fractured rocks. An effective approach to determine the UCS and to investigate the behaviours of rock materials under unconfined compression is essential in the majority of research fields of rock mechanics. The experimental configuration for the unconfined compression test, suggested by the protocols of the ASTM standard, has some limitations which affect the accuracy in determination of the real UCS. Among several alternative configurations proposed, the Mogi’s configuration seems to be the most appropriate one. Therefore, the ASTM and Mogi’s configurations were used to perform the tests on a medium strength rock material, i.e. Pietra Serena sandstone. The results using two configurations were discussed in terms of the differences. The tests were also replicated in LSDYNA using a finite element method(FEM) coupled smooth particle hydrodynamics(SPH) *** technique is employed in this study due to its capabilities to cope with large deformation issues related to the rocks. An advanced material model, called the Karagozian and Case Concrete(KCC) model,is implemented in the numerical simulations. The KCC model consists of three independent fixed failure surfaces and it can consider the damage accumulation based on the current state of stress among these failure surfaces. An equation-of-state(EOS) is used in conjunction with KCC material model for decoupling the volumetric and deviatoric responses. The numerical and experimental results were finally compared with the focus on the stress-strain diagram and the failure patterns. The comparison shows that the numerical results are in good agreement with the experime

关键词： Pietra Serena sandstone Unconfined compression Mogi's configuration Karagozian and Case Concrete(KCC) model Finite element method(FEM) Smooth particle hydrodynamics(SPH)

Multiple aspects of the maternal reproductive investmentin a polytocous species:What do mothers really control?

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Current Zoology 2023年第2期69卷 136-142页

作者： Rudy Brogi Roberta Chirichella Enrico Merli marco Apollonio Department of Veterinary Medicine University of Sassarivia Vienna 2I-07100 SassariItaly Department of Humanities and Social Sciences University of Sassarivia Roma 151I-07100 SassariItaly

One of the factors facilitating the expansion and proliferation of wild boar Sus scrofa is the plasticity of its reproductive ***,the real influence of maternal and environmental factors on number and sex of the offspring is stll *** the litter size was shown to be related with the maternal condition,the strength of this relation remains to be understood,together with the possible role played by environmental ***,it is unclear whether wild boar females can adjust their offspring *** investigated multiple aspects of wild boar maternal investment by means of a 10-year dataset of female reproductive traits and a set of biologically meaningful environmental *** maternal condition slightly affected the litter size but not the offspring sex,and environment did not affect the litter size or the offspring ***,mothers did not cope with the higher costs entailed by producing sons by placing them in the most advantageous intrauterine position,nor by allocating less resources on *** set of results showed that the female reproductive investment is quite rigid in comparison with other aspects of wild boar reproductive *** boar females seem to adopt a typical rstrategy,producing constantly large litters and allocating resources on both sexes regardless of internal and external *** strategy may be adaptive to cope with environmental unpredictability and an intense human harvest,contributing to explain the extreme success of wild boar within human-dominated landscapes.

关键词： investment life history litter size reproduction sex allocation wild boar

Persistent half-metallic ferromagnetism in a(111)-oriented manganite superlattice

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npj Computational Materials 2022年第1期8卷 727-734页

作者： Fabrizio Cossu Heung-Sik Kim Biplab Sanyal igor Di marco Department of Physics and institute of Quantum Convergence and Technology Kangwon National UniversityChuncheon24341Korea Asia Pacific Center for Theoretical Physics Pohang37673Korea Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120UppsalaSweden Department of Physics POSTECHPohang37673Korea

We employ electronic structure calculations to show that a(111)-oriented(LaMnO_(3))_(12)∣(SrMnO_(3))_(6)superlattice retains a half-metallic ferromagnetic character despite its large *** link this behaviour to the strain and the octahedral connectivity between the *** also gives rise to breathing modes,which are coupled to charge and spin oscillations,whose components have a pure e_(g)*** interestingly,the magnetisation reaches its maximum value inside the LaMnO_(3)region and not at the interface,which is fundamentally different from what observed for the(001)*** inter-atomic exchange coupling shows that the magnetic order arises from the double-exchange mechanism,despite competing interactions inside the SrMnO_(3)***,the van Vleck distortions and the spin oscillations are crucially affected by the variation of Hund’s exchange and charge doping,which allows us to speculate that our system behaves as a Hund’s metal,creating an interesting connection between manganites and nickelates.

关键词： metallic exchange superlattice

A new general index of home range overlap and segregation:the Lesser Kestrel in Southern italy as a case study

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Avian Research 2021年第1期12卷 108-117页

作者： Alessandro Ferrarini Giuseppe Giglio Stefania Caterina Pellegrino marco Gustin Conservation Department LIPU-BirdLife Italy(Lega Italiana Protezione Uccelli)Via Udine 3/a43122 ParmaItaly

Background:There is increasing interest in evaluating home-range overlap(or,otherwise,segregation)between bird species,and between or within bird populations,to inform spatial *** far,studies of home-range overlap typically make use of comparisons between pairs of individuals,populations or species,and return a matrix of pairwise overlaps(e.g.,percent overlaps).However,when the number of individuals,populations or species to be compared is elevated,an overlarge overlap matrix is difficult to interpret from an ecological ***:We propose here a new,conceptually simple and computationally efficient index(general overlap index;GOi)for the ready computation within GiS of home range overlap of an arbitrarily large number(i.e.,n≥2)of individuals,populations or *** the number of home ranges to be compared,GOi always returns a single score between 0 and *** a case study,we applied our index to 24,074 GPS points of 10 Lesser Kestrels(Falco naumanni)in order to estimate within-colony and between-colony overlaps in two neighboring colonies in Southern ***:Within-colony overlap was elevated for both colonies(96.41%at Cassano delle Murge,n=5 individuals;81.38%at Santeramo in Colle,n=5 individuals),while between-colony overlap was low(19.12%;n=2 colonies)and,after a randomization procedure,more spatially-segregated than expected by ***:Modern biotelemetry offers huge amounts of data describing the space use of animal *** use of intuitive and straightforward indices,like GOi,can be useful to promptly extract ecological information from such an amount of data(*** change in space use over successive years,evaluating the reliability of various home-range estimators).

关键词： Between-colony overlap Falco naumanni Home range randomization Overlap estimator Spatial segregation Within-colony overlap

Optimal solar sail transfers to circular Earth-synchronous displaced orbits

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Astrodynamics 2020年第3期4卷 193-204页

作者： Alessandro A.Quarta Giovanni Mengali marco Bassetto Department of Civil and industrial Engineering University of PisaPisa I-56122Italy

The aim of this paper is to evaluate the minimum flight time of a solar sail-based spacecraft towards Earth-synchronous(heliocentric)circular displaced *** are special displaced non-Keplerian orbits characterized by a period of one year,which makes them suitable for the observation of Earth’s polar *** solar sail is modeled as a flat and purely reflective film with medium-low performance,that is,with a characteristic acceleration less than one millimeter per second *** from a circular parking orbit of radius equal to one astronomical unit,the optimal steering law is sought by considering the characteristic acceleration that is required for the maintenance of the target Earth-synchronous displaced *** indirect approach used for the calculation of the optimal transfer trajectory allows the minimum flight time to be correlated with several Earth-synchronous displaced orbits,each one being characterized by given values of Earth-spacecraft distance and displacement over the *** proposed mathematical model is validated by comparison with results available in the literature,in which a piecewise-constant steering law is used to find the optimal flight time for a transfer towards a one-year Type i non-Keplerian orbit.

关键词： solar sail synchronous displaced orbit trajectory optimization