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Post-fire recovery of Puya raimondii, vegetation and birds in the puna of Huascarán National Park, Perú

Journal of mountain Science 2024年第1期21卷 20-32页

作者： mery l.SUNI Giovana P.VADIllO César ARANA Enoc JARA-PENA letty SAlINAS m.Estela PONCE Paul m.RAmSAY Plant Physiology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Natural History museum Universidad Nacional Mayor de San MarcosLima 15072Peru Applied Phytology laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Statistics Faculty of Mathematical SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Chemical and Biological Sciences Universidad de las Américas PueblaSan Andrés Cholula CP Cholula CP 72810Mexico

A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.

关键词： Burning Plant biomass Trophic guilds Andes Giant rosette plants

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A Theoretically Grounded Question Answering Data Set for Evaluating machine Common Sense

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Data Intelligence 2024年第1期6卷 1-28页

作者： Henrique Santos Ke Shen Alice m.mulvehill mayank Kejriwal Deborah l.mcGuinness Rensselaer Polytechnic Institute Troy NY Information Sciences Institute Marina del Rey CA

Achieving machine common sense has been a longstanding problem within Artificial *** far,benchmark data sets that are grounded in a theory of common sense and can be used to conduct rigorous,semantic evaluations of common sense reasoning(CSR)systems have been *** expectation of the AI community is that neuro-symbolic reasoners can help bridge this gap towards more dependable systems with common *** propose a novel benchmark,called Theoretically Grounded common sense Reasoning(TG-CSR),modeled as a set of question answering instances,with each instance grounded in a semantic category of common sense,such as space,time,and *** benchmark is few-shot i.e.,only a few training and validation examples are provided in the public release to avoid the possibility of *** from recent evaluations suggest that TG-CSR is challenging even for state-of-the-art statistical *** to its semantic rigor,this benchmark can be used to evaluate the common sense reasoning capabilities of neuro-symbolic systems.

关键词： reasoning Intelligence instance

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measurement of cryoelectronics heating using a local quantum dot thermometer in silicon

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Chip 2024年第3期3卷 1-7页

作者： mathieu de Kruijf Grayson m.Noah Alberto Gomez-Saiz John J.l.morton m.Fernando Gonzalez-Zalba Quantum motion 9 Sterling WayLondon N79HJUnited Kingdom london Centre for Nanotechnology University College London17-19 Gordon StreetLondon WC1H 0AHUnited Kingdom

Silicon technology offers the enticing opportunity for monolithic integration of quantum and classical electronic ***,the power consumption levels of classical electronics may compromise the local chip temperature and hence affect the fidelity of qubit *** the current work,a quantum-dot-based thermometer embedded in an industry-standard silicon fieldeffect transistor(FET)was adopted to assess the local temperature increase produced by an active FET placed in close *** impact of both static and dynamic operation regimes was thoroughly *** the FET was operated statically,a power budget of 45 nW at 100-nm separation was found,whereas at 216μm,the power budget was raised to 150μ*** temperature increase for the switch frequencies tested up to 10 mHz was observed when operating *** current work introduced a method to accurately map out the available power budget at a distance from a solid-state quantum processor,and indicated the possible conditions under which cryoelectronics circuits may allow the operation of hybrid quantum-classical systems.

关键词： Quantum dot Cryogenic electronics Thermometry Spin qubit Heat management

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Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.madhu H.C.manjunatha N.Sowmya B.m.Rajesh l.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)Cr+^(243)Am,23.2 fb at 236 meV for ^(54)Cr+^(247)Cm,95.6 fb at 240 meV for ^(53)Cr+248Bk,and 1.33 fb at 242 meV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

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A Tutorial on Federated learning from Theory to Practice:Foundations,Software Frameworks,Exemplary Use Cases,and Selected Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 824-850页

作者： m.Victoria luzón Nuria Rodríguez-Barroso Alberto Argente-Garrido Daniel Jiménez-lópez Jose m.moyano Javier Del Ser Weiping Ding Francisco Herrera Department of Software Engineering Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Department of Computer Science and Artificial Intelligence Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Department of Communications Engineering University of the Basque Country(UPV/EHU)and also with TECNALIABasque Research&Technology Alliance(BRTA)Spain School of Information Science and Technology Nantong UniversityNantong 226019China

When data privacy is imposed as a necessity,Federated learning(Fl)emerges as a relevant artificial intelligence field for developing machine learning(ml)models in a distributed and decentralized *** allows ml models to be trained on local devices without any need for centralized data transfer,thereby reducing both the exposure of sensitive data and the possibility of data interception by malicious third *** paradigm has gained momentum in the last few years,spurred by the plethora of real-world applications that have leveraged its ability to improve the efficiency of distributed learning and to accommodate numerous participants with their data *** virtue of Fl,models can be learned from all such distributed data sources while preserving data *** aim of this paper is to provide a practical tutorial on Fl,including a short methodology and a systematic analysis of existing software ***,our tutorial provides exemplary cases of study from three complementary perspectives:i)Foundations of Fl,describing the main components of Fl,from key elements to Fl categories;ii)Implementation guidelines and exemplary cases of study,by systematically examining the functionalities provided by existing software frameworks for Fl deployment,devising a methodology to design a Fl scenario,and providing exemplary cases of study with source code for different ml approaches;and iii)Trends,shortly reviewing a non-exhaustive list of research directions that are under active investigation in the current Fl *** ultimate purpose of this work is to establish itself as a referential work for researchers,developers,and data scientists willing to explore the capabilities of Fl in practical applications.

关键词： Data privacy distributed machine learning federated learning software frameworks

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Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental materials 2024年第1期7卷 229-237页

作者： Veniero lenzi José P.B.Silva Břetislav Šmíd Vladimir matoín Cosmin m.Istrate Corneliu Ghica Judith l.macmanus-Driscoll luís marques Physics Center of minho and Porto Universities(CF-Um-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal laboratory of Physics for materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of materials Physics 105 bis Atomistilor 077125Magurele Romania Department of materials Science and metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： U.S.mahabaleshwar G.P.Vanitha l.m.Pérez Emad H.Aly I.Pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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Epidemiology of insertional and midportion Achilles tendinopathy in runners:A prospective cohort study

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Journal of Sport and Health Science 2024年第2期13卷 256-263页

作者： Wenbo Chen Kyra l.A.Cloosterman Sita m.A.Bierma-Zeinstra marienke van middelkoop Robert-Jan de Vos Department of Orthopaedic Surgery and Sports medicine Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of General Practice Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of Sports medicine Huashan HospitalFudan UniversityShanghai 200040China

Background:Achilles tendinopathy(AT)is a common problem among *** is only limited evidence for risk factors for AT,and most studies have not defined the AT *** study has compared the incidence and risk factors between insertional AT and midportion AT,though they are considered *** study aimed to assess incidence and risk factors of AT based on data from a large prospective *** secondary aim was to explore differences in risk factors between insertional and midportion ***:Participants were recruited from among registered runners at registration for running *** were completed at baseline,1 month before the event,1 week before the event,and 1 month after the *** concerning demographics,training load,registered events,and running-related injuries were collected at *** follow-up questionnaires collected information about new injuries.A pain map was used to diagnose midportion and insertional *** primary outcome was the incidence of *** logistic regression analysis was applied to identify risk factors for the ***:We included 3379 participants with a mean follow-up of 20.4 *** incidence of AT was 4.2%.The proportion of insertional AT was 27.7%and of midportion AT was 63.8%;the remaining proportion was a combined type of insertional and midportion *** had a significantly higher incidence(5%,95%confidence interval(95%CI):4.1%-6.0%)than women(2.8%,95%CI:2.0%-3.8%).AT in the past12 months was the most predominant risk factor for new-onset AT(odds ratio(OR)=6.47,95%CI:4.27-9.81).This was similar for both subcategories of AT(insertional:OR=5.45,95%CI:2.51-11.81;midportion:OR=6.96,95%CI:4.24-11.40).Participants registering for an event with a distance of 10/10.55 km were less likely to develop a new-onset AT(OR=0.59,95%CI:0.36-0.97)or midportion AT(OR=0.47,95%CI:0.23-0.93).Higher age had a significant negative association with insertional AT(OR=0.97,95%CI:0.9

关键词： Achilles tendon injury Incidence Risk factor Running-related injury

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.l.Zhu S.m.Weng P.li X.F.li H.Ai H.R.Pan Z.m.Sheng Key laboratory for laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

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巴西油气勘探开发历程:从陆上到超深水

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石油勘探与开发 2024年第4期51卷 796-806页

作者： ANJOS Sylvia m C SOmBRA Cristiano l SPADINI Adali R 巴西国家石油公司里约热内卢20231-030巴西

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变... 详细信息

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变、重大突破和关键理论技术。巴西国家石油公司(简称巴西国油)自1953年成立以后的15年间,在陆上古生界克拉通盆地和断陷盆地进行了勘探,并于断块和三角洲砂体圈闭获得了一些中小型油气发现。20世纪70年代,应用重力流沉积模式和高质量三维地震等勘探新技术,在坎波斯盆地浅水中发现Namorado和Enchova等油田,随后深水盐上勘探获得突破,成功发现marlim、Roncador等大型油田。21世纪初,通过盐下含油气系统、碳酸盐岩成储成藏模式和核磁共振测井等理论技术攻关,推动桑托斯盆地下白垩统湖相碳酸盐岩陆续获得Tupi(lula)、Buzios、mero等世界级超深水盐下大油田的系列重大发现。在复杂的深水作业环境下,油气开发工程面临巨大挑战,巴西国油通过启动深水研发计划(PROCAP),开发并实施窄压力窗口控压钻井、加压钻井液帽钻井、多段智能完井、水下采油及浮式生产平台开发和流动保障等关键技术,显著提升了钻完井、油气田开发和输运的效率及安全性。此外,在浮式采储卸油系统建产规模受限的情况下,推进全球最大规模的CO_(2)捕集、驱油利用与埋存工程(CCUS-EOR),有效减少温室气体排放并提高了原油采收率。上述理论技术的发展和应用,也为全球深水油气勘探开发提供了宝贵经验。未来巴西油气勘探将继续聚焦深水盐下碳酸盐岩和盐上浊积岩,并在古生界天然气等勘探领域持续寻求新的发现,同时通过技术创新和战略合作,促进巴西石油天然气行业的可持续发展。

关键词：巴西深水盐下勘探坎波斯盆地桑托斯盆地浊积岩湖相碳酸盐岩深水开发流动保障

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