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Why did life develop on the surface of the Earth in the Cambrian？

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Geoscience Frontiers 2016年第6期7卷 865-873页

作者： carlo doglioni Johannes Pignatti Max Coleman Department of Earth Sciences Sapienza University 00185 Rome Italy NASA Jet Propulsion Laboratory California Institute of Technology Pasadena CA 91109 USA NASA Astrobiology Institute USA

Life was limited for most of Earth＇s history, remaining at a primitive stage and mostly marine until about 0.55 Ga. In the Paleozoic, life eventually exploded and colonized the continental realm. Why had there been such a long period of delayed evolution of life？ Early life was dominated by Archaea and Bacteria, which can survive ionizing radiation better than other organisms. The magnetic field preserves the atmosphere, which is the main shield of UV radiation. We explore the hypothesis that the Cambrian explosion of life could have been enabled by the increase of the magnetic field dipole intensity due to the solidification of the inner core, caused by the cooling of the Earth, and the concomitant decrease with time of the high-energy solar flux since the birth of the solar system. Therefore, the two phenomena could be responsible for the growth and thickening of the atmosphere and the development of land surface life.

关键词： Origin of lifeInner core solidificationSolar ionizing radiations

Tidal drag and westward drift of the lithosphere

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Geoscience Frontiers 2023年第6期14卷 102-116页

作者： Vincenzo Nesi Oscar Bruno Davide Zaccagnino Corrado Mascia carlo doglioni Dipartimento di Matematica Guido Castelnuovo Piazzale Aldo Moro5Roma 00185Italy Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata605Roma 00143Italy Computing and Mathematical Sciences Department Caltech1200 E.California Blvd.MC 305-16Pasadena 91125CAUSA Dipartimento di Scienze della Terra Piazzale Aldo Moro5Roma 00185Italy

Tidal forces are generally neglected in the discussion about the mechanisms driving plate tectonics despite a worldwide geodynamic asymmetry also observed at subduction and rift *** tidal drag could theoretically explain the westerly shift of the lithosphere relative to the underlying ***,viscosity in the asthenosphere is apparently too high to allow mechanical decoupling produced by tidal ***,we propose a model for global scale geodynamics accompanied by numerical simulations of the tidal interaction of the Earth with the Moon and the *** provide for the first time a theoretical proof that the tidal drag can produce a westerly motion of the lithosphere,also compatible with the slowing of the Earth’s rotational *** results suggest a westerly rotation of the lithosphere with a lower bound ofω≈(0.1-0.2)°/Myr in the presence of a basal effective shear viscosityη≈10^(16)Pa-s,but it may rise toω>1°/Myr with a viscosity ofη≈≤3×10^(14)Pa-s within the Low-Velocity Zone(LVZ)atop the *** faster velocity would be more compatible with the mainstream of plate motion and the global asymmetry at plate *** on these computations,we suggest that the super-adiabatic asthenosphere,being vigorously convecting,may further reduce the viscous coupling within the LVZ Therefore,the combination of solid Earth tides,ultra-low viscosity LVZ and asthenospheric polarized small-scale convection may mechanically satisfy the large-scale decoupling of the lithosphere relative to the underlying *** plate motions are explained because of lateral viscosity heterogeneities at the base of the lithosphere,which determine variable lithosphere-asthenosphere decoupling and plate interactions,hence plate tectonics.

关键词： Tidal drag Plate motions Polarized plate tectonics Lithosphere-asthenosphere interaction

Tectonically asymmetric Earth:From net rotation to polarized westward drift of the lithosphere

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Geoscience Frontiers 2015年第3期6卷 401-418页

作者： carlo doglioni Eugenio Carminati Mattia Crespi Marco Cuffaro Mattia Penati Federica Riguzzi Dipartimento di Scienze della Terra Sapienza Universita di Roma DITS-Area di Geodesia e Geomatica Sapienza Universita di Roma Istituto di Geologia Ambientale e Geoingegneria CNR MOX-Dipartimento di Matematica Politecnico di Milano Istituto Nazionale di Geofisica e Vulcanologia Sez.CNTRomeItaly

The possibility of a net rotation of the lithosphere with respect to the mantle is generally overlooked since it depends on the adopted mantle reference frames, which are arbitrary. We review the geological and geophysical signatures of plate boundaries, and show that they are markedly asymmetric worldwide. Then we compare available reference frames of plate motions relative to the mantle and discuss which is at best able to fit global tectonic data. Different assumptions about the depths of hotspot sources （below or within the asthenosphere, which decouples the lithosphere from the deep mantle） predict different rates of net rotation of the lithosphere relative to the mantle. The widely used no-net-rotation （NNR） reference frame, and low （〈0.2°-0.4°/Ma） net rotation rates （deep hotspots source） predict an average net rotation in which some plates move eastward relative to the mantle （e.g., Nazca）. With fast （〉1°/Ma） net rotation （shallow hotspots source）, all plates, albeit at different velocity, move westerly along a curved trajectory, with a tectonic equator tilted about 30° relative to the geographic equator. This is consistent with the observed global tectonic asymmetries.

关键词： Asymmetric plate tectonics Plate motions Westward drift Mantle convection

The westward lithospheric drift,its role on the subduction and transform zones surrounding Americas:Andean to cordilleran orogenic types cyclicity

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Geoscience Frontiers 2020年第4期11卷 1219-1229页

作者： Eugenio Aragon Fernando D'Eramo Marco Cuffaro carlo doglioni Eleonora Ficini Lucio Pinotti Silvina Nacif Manuel Demartis Irene Hernando Tomas Fuentes Centro de Investigaciones Geologicas Universidad Nacional de La PlataArgentina Instituto de Ciencias de La Tierra Biodiversidad y Ambiente(ICBIA).Departamento de GeologíaUniversidad Nacional de Río Cuarto(UNRC-CONICET)Ruta 36 Km 601Río CuartoCordobaArgentina Istituto Geologia Ambientale e Geoingegneria-CNR Italy Dipartimento de Scienzedella Terra Universita La SapienzaItaly Instituto Geofísico Sismologico F.Volponi Universidad Nacional de San JuanArgentina

We investigate the effect of the westerly rotation of the lithosphere on the active margins that surround the Americas and find good correlations between the inferred easterly-directed mantle counterflow and the main structural grain and kinematics of the Andes and Sandwich arc *** the Andes,the subduction zone is shallow and with low dip,because the mantle flow sustains the slab;the subduction hinge converges relative to the upper plate and generates an uplifting doubly verging *** Sandwich Arc is generated by a westerly-directed SAM(South American) plate subduction where the eastward mantle flow is steepening and retreating the subduction *** this context,the slab hinge is retreating relative to the upper plate,generating the backarc basin and a low bathymetry single-verging accretionary *** Central America,the Caribbean plate presents a more complex scenario:(a) To the East,the Antilles Arc is generated by westerly directed subduction of the SAM plate,where the eastward mantle flow is steepening and retreating the subduction zone.(b) To the West,the Middle America Trench and Arc are generated by the easterly-directed subduction of the Cocos plate,where the shallow subduction caused by eastward mantle flow in its northern segment gradually steepens to the southern segment as it is infered by the preexisting westerly-directed subduction of the Caribbean *** the frame of the westerly lithospheric flow,the subduction of a divergent active ridge plays the role of introducing a change in the oceanic/continental plate’s convergence angle,such as in NAM(North American)plate with the collision with the Pacific/Farallon active ridge in the Neogene(Cordilleran orogenic type scenario).The easterly mantle drift sustains strong plate coupling along NAM,showing at Juan de Fuca easterly subducting microplate that the subduction hinge advances relative to the upper *** lower/upper plate convergence coupling also applies along strike to the neigh

关键词： Lithospheric drift Converging hinge Diverging hinge Slab rollbakc Terranes

AC ripple on DC voltage:Experimental and theoretical investigation of the impact on accelerated ageing in electrical insulation

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High Voltage 2024年第4期9卷 902-910页

作者： Giovanni Gardan Gian carlo Montanari Dipartimento di Ingegneria Industriale Universita degli Studi di PadovaPadovaItaly Center for Advanced Power Systems Florida State UniversityTallahasseeFloridaUSA

With the increasing penetration of DC systems into the high voltage and medium voltage power industry,DC voltage is becoming common for distribution/transmission and to supply different typologies of *** allowable extent of AC ripple superimposed to DC,and its effect on insulation ageing,is a long-term discussed *** most harmful phenomenon causing extrinsic ageing acceleration and insulation system premature failure is partial discharges(PD);thus,the risk of incepting PD due to AC ripple could become a primary issue for electrical asset equipment *** this work,the impact of AC sinusoidal ripple on insulation system life and reliability is dealt with,considering both intrinsic and extrinsic ageing but focusing on the latter,that is,the PD *** are performed to assess how the jump voltage(due to AC ripple)and the DC component impact on PD activity in terms of amplitude and repetition *** the first time,the correlation between the magnitude of jump voltage associated with ripple and PD inception is established,shedding a light on the allowable ripple extent which does not impact significantly on ageing and premature insulation *** approach can provide straightforward tools for design specification and ageing inference of insulation systems.

关键词： impact insulation electrical

Experimental evaluation of mechanical compression of lattice trusses made with Ti6Al4V for aerospace use

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Chinese Journal of Aeronautics 2024年第5期37卷 520-532页

作者： carlo Giovanni FERRO Sara VARETTI Paolo MAGGIORE Department of Mechanical and Aerospace Engineering Politecnico di TorinoCorso Duca degli AbruzziTorino 10124Italy

Lattice structures are three-dimensional structures composed of repeated geometrical shapes with multiple interconnected nodes,providing high strength-to-weight ratios,customizable properties,and efficient use of materials.A smart use of materials leads to reduced fuel consumption and lower operating costs,making them highly desirable for aircraft ***,the customizable properties of lattice structures allow for tailoring to specific design requirements,leading to improved performance and safety for *** advantages make lattice structures an important focus for research and development in the aviation *** paper presents an experimental evaluation of the mechanical compression properties of lattice trusses made with Ti6Al4V,designed for use in an anti-ice *** truss structures were manufactured using additive manufacturing techniques and tested under compressive loads to determine mechanical *** showed that lattice trusses exhibited high levels of compressive strength,making them suitable for use in applications where mechanical resistance and durability are critical,such as in anti-ice *** also highlight the potential of additive manufacturing techniques for the fabrication of lattice trusses with tailored mechanical *** study provides valuable insights into the mechanical behavior of Ti6Al4V lattice trusses and their potential applications in anti-ice systems,as well as other areas where high strength-to-weight ratios are *** results of this research contribute to the development of lightweight,efficient,and durable anti-ice systems for use in aviation and other industries.

关键词： Additive Manufacturing(AM) Selective Laser Sintering(SLM) Anti ice systems Lattice structures Aircraft on board systems Design of Experiments(DOE)

Transition from continental collision to tectonic escape? A geophysical perspective on lateral expansion of the northern Tibetan Plateau

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Transition from continental collision to tectonic escape? A ...

Local recurrence rate as quality indicator in surgery for pancreatic cancer?

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Yangfan Deng Giuliano F Panza Zhongjie Zhang Fabio Romanelli Ting Ma carlo doglioni Peng Wang Xuemei Zhang Jiwen Teng State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences Department of Mathematics and Geosciences University of Trieste Institute of Geophysics China Earthquake Administration International Centre for Theoretical Physics SAND group Department of Earth Sciences La SapienzaUniversity of Roma

A number of tectonic models have been proposed for the Tibetan Plateau, which origin, however, remains poorly understood. In this study, investigations of the shear wave velocity(Vs) and density(ρ) structures of the crust and upper mantle evidenced three remarkable features:(1) There are variations in Vs and ρ of the metasomatic mantle wedge in the hanging wal of the subduction beneath different tectonic blocks of Tibet, which may be inferred as related to the dehydration of the downgoing slab.(2) Sections depicting gravitational potential energy suggest that the subducted lithosphere is less dense than the ambient rocks, and thus, being buoyant, it cannot be driven by gravitational slab *** subduction process can be inferred by the faster SW-ward motion of Eurasia relative to India as indicated by the plate motions relative to the mantle. An opposite NE-ward mantle flow can be inferred beneath the Himalaya system, deviating E and SE-ward toward China along the tectonic equator.(3) The variation in the thickness of the metasomatic mantle wedge suggests that the leading edge of the subducting Indian slab reaches the Bangoin-Nujiang suture(BNS), and the metasomatic mantle wedge overlaps with a region with poor Sn-wave propagation in north Tibet. The metasomatic layer, north of the BNS, deforms in the E-W direction to accommodate lithosphere shortening in south Tibet.

关键词： Tibetan plateau Continental colision System transition Net rotation of the lithosphere

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 548-550页

作者： carlo Alberto Pacilio Alessandro Cucchetti Giorgio Ercolani General and Oncologic Surgery Unit Morgagni-Pierantoni HospitalAUSL RomagnaVia Carlo Forlanini 3447121ForlìItaly Department of Medical and Surgical Sciences Alma Mater StudiorumUniversity of BolognaVia Massarenti 940138BolognaItaly

To the Editor: As we all know, even with the current advancements regarding novel chemotherapy regimens, patients affected by pancreatic cancer(PC) have an extremely dismal prognosis(5-year survival rate 12% for all stages in the National Cancer Institute SEER database). Among the patients undergoing surgical treatment, the prognosis is mostly affected by recurrence. PC after surgery has mainly four patterns of recurrence, isolated or variously associated with each other: local, lymph nodal, peritoneal or distant(liver, lung, other sites).

关键词： surgery prognosis cancer

Introduction to the Special Issue on Recent Developments on Computational Biology-I

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2261-2264页

作者： carlo Cattani Haci Mehmet Baskonus Armando Ciancio Engineering School(DEIM) University of TusciaViterbo01100Italy Department of Mathematics and Science Education Faculty of EducationHarran UniversitySanliurfa63190Turkey Universitàdegli Studi di Messina Dipartimento di Scienze BiomedicheOdontoiatriche e delle Immagini Morfologiche e FunzionaliMessina98122Italy

In modern time,experts started to use interdisciplinary properties with the development of technology and ***,these disciplines provide more sophisticated properties of real-world *** this sense,some models need to be investigated by using revised and modified traditional *** first discipline is the applied sciences such as physics,engineering,mechanics,electricity,biology,economy and mathematical applications[1-5].In this stage,many methods[5-10]are developed and *** uncover the deep properties of problems is to use the main properties of such interdisciplinary ***,works conducted on such mathematical models including non-local operators,partial,ordinary and integer order have introduced a deeper investigation of problems for *** using technological tools,expertsmay observe more realistic and exact results of models.

关键词： properties. integer operators