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Synchronous formation of the‘forearc’Bay of Islands ophiolite and its basal high-temperature metamorphic sole constrained by U-Pb zircon ages

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Geoscience frontiers 2023年第6期14卷 234-272页

作者： Weiyao Yan John f.Casey department of Earth and Atmospheric Sciences University of HoustonHoustonTXUSA

The welded metamorphic sole at the base of the Bay of Islands Ophiolite Complex(BOIC)in the Northern Appalachians of Newfoundland shows a typical inverted pressure-temperature(P-T)metamorphic gradient from HT-MP granulite to LT-LP greenschist *** incorporates mafic volcanic/plutonic protoliths mixed with pelagic,hemi-pelagic and coarser epiclastic sedimentary *** la-ICP-MS U–Pb concordia ages,trace elements,and Ti-in-zircon geothermometry for -250 zircon analyses from three metabasites of the upper HT sole amphibolites with N-MORB-like protoliths are *** samples collected within meters of the ophiolite peridotite-sole contact of the Blow Me Down Mountain and North Arm Mountain massifs yielded the oldest comparable concordia ages of 487.7±2.6 Ma and 489.1±3.1 Ma,respectively,that are both within error of the igneous age of 488.3±1.5 Ma of the directly overlying BOIC ophiolite,which formed at a supra-subduction zone(SSZ)forearc spreading center.A third slightly younger age of 484.2±2.4 Ma was obtained for an upper HT amphibolite sample with similar phase assemblages but collected30 m below the peridotite contact of the Table Mountain *** crystals analyzed have similar size and morphologies,subparallel rare earth element(REE)variation patterns,and steep heavy REE-enrichments((Lu/Gd)_(cn)>20),significant positive Ce anomalies(dominantly>5)and slight positive to dominantly negative Eu anomalies(1.2–0.4).Zircon shows Th/U mean values of 0.37–0.48 with little to no rim to core *** Ti-in-zircon mean crystallization temperatures range from764–787℃.These neocrystallized zircon crystals appear to be derived from thin leucosomes within the three *** other samples also from the upper HT sole show evidence of inherited detrital zircon with core dates spanning the Cambrian Notre Dame Arc through older laurentian-like basement and rift age *** of the sole took place below a hot forearc asthenospheric wed

关键词： Ophiolite metamorphic sole U-Pb zircon ages Hot subduction interface Supra-subduction forearc spreading center Arc-continent collision Taconic Orogeny

Weld Models Incorporating the HAZ Phase Transformation Effects, Comparison between Experimental and Numerical Results

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Journal of Shanghai Jiaotong university(Science) 2000年第1期5卷 107-113页

作者： V. VINCENT(1-2), J.f. JULLIEN(1), f. fOUQUET(1) and V. CANO(3) (1) INSA de Lyon, 20 Avenue Albert Einstein, 69621 Villeurbanne Cedex, france (2) fRAMATOME, 92084 Paris la defense Cedex, france (3) EDf-deR, 1 Avenue du General de Gaulle 92141 Clamart Cedex

Numerical simulations of a representative test of welding process are presented in this paper. A french vessel steel, which involves metallurgical phase transformations in solid state is considered in this work. The aim is to validate the thermal-metallurgical-mechanical models taking into account the metallurgical transformations in the finite element codes Sysweld (framasoft) and Code Aster (EDf). The test is performed on a thin disc submitted to a thermal cycle loading by means of a CO2 laser beam, which leads to metallurgical phase transformations. The thermal, metallurgical and mechanical numerical results have been compared to the experimental results (temperatures, sizes of transformed zones, displacements and residual stresses and strains). The main objective of the numerical analysis is to have some results which enable to give some indications on the ability of the numerical codes to describe the observed phenomena. for that, it is necessary to simulate accurately the thermo-metallurgical history. The comparison of experimental results with the numerical ones leads to some interesting orientations related to the capacities of the considered models to describe the observed phenomena.

关键词： Material austeno-ferritic steel tank nuclear reactor welding experimental device numerical simulation metallurgical behaviour thermal behaviour residual stresses

Chip-based squeezing at a telecom wavelength

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Photonics Research 2019年第7期7卷 10-13页

作者： f.Mondain T.Lunghi A.Zavatta E.Gouzien f.Doutre M.de Micheli S.Tanzilli V.D'Auria Universite Cote d'Azur CNRSInstitut de Physique de NiceParc Valrose06108 Nice Cedex 2France Istituto Nazionale di Ottica (INO-CNR) largo Enrico fermi 6 50125 FirenzeItaly LENS and department of Physics Universita di Firenze50019 Sesto FiorentinoFirenzeItaly

We demonstrate a squeezing experiment exploiting the association of integrated optics and telecom technology as key features for compact, stable, and practical continuous variable quantum optics. In our setup, squeezed light is generated by single-pass spontaneous parametric down conversion on a lithium niobate photonic circuit and detected by a homodyne detector whose interferometric part is directly integrated on the same platform. The remaining parts of the experiment are implemented using commercial plug-and-play devices based on guided-wave technologies. We measure, for a CW pump power of 40 mW, a squeezing level of -2.00±0.05 dB (anti-squeezing 2.80 ±0.05 dB), thus confirming the validity of our approach and opening the way toward miniaturized and easy-to-handle continuous variable-based quantum systems.

关键词： squeezing association single-pass

Relationship between Category of Weight and Threshold of Maximum Oxidation of Lipids in Congolese Judoists

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Journal of Biosciences and Medicines 2017年第7期5卷 74-83页

作者： Jean Georges André Moulongo Alphonse Massamba Jean Itoua Okemba Massala Kitanga fêtra Néla Packa Bernard Tchissambou laboratory of Physiology of the Effort and Biomechanics Higher Institute of Physical and Sporting Education Marien Ngouabi University Brazzaville Congo Martial Arts and Combat Sports Research Unit Fundamental and Applied Human Movement Sciences Laboratory Higher Institute of Physical Education and Sports Marien Ngouabi University Brazzaville Congo

Background: One of the goals for training in judo is to mimic real situations. In subsaharian countries;there is a lack of knowledge considering relation between category of weight and threshold maximum oxidation of lipids. Objectives: The main objectives of this study were to analyze the effect of category of weight on lipoxmax and to identify the zones of target intensities corresponding to lipoxmax. Materials and Methods:Twenty four male well-training judoists, divided in two groups according to weight, were evaluated during calorimetry effort’ test. for this situation, cardiorespiratory parameters (HR, VO2, VO2max), blood parameter (lactatemia), anthropometric variables and zones of target corresponding to lipox were evaluated. for statistical analysis, Shapiro-Wilks test was used to compare all the data and differences were confirmed by one-way variance. Results: No significant differences were observed among two groups for target intensities to lipox. The judoists of group 1 were aged to 24.1 ± 5.9 years with 1.78 ± 0.07 m versus 20.4 ± 1.6 years with 1.86 ± 0.04 m. Primary results indicated higher intensities for lipoxmax. Also, values of power (% LDC) and VO2 and were significantly higher in the judoists for group 2, with respectively: 45.3 ± 10.2 and 46.4 ± 8.6 ml/min versus 38.2 ± 7.2 and 31.3 ± 7.6 ml/min. Conclusion: High weight in judoists induces high intensities of lipoxmax and change oxidation of lipids markers following training.

关键词： Judo Oxidation of Lipids Lipoxmax Weight Category

Unraveling one billion years of geological evolution of the southeastern Amazonia Craton from detrital zircon analyses

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Geoscience frontiers 2022年第5期13卷 129-152页

作者： Camille Rossignol Paul Yves Jean Antonio francesco Narduzzi Eric Siciliano Rego Lívia Teixeira Romário Almeida de Souza Janaína N.Ávila Marco A.L.Silva Cristiano lana Ricardo I.f.Trindade Pascal Philippot departamento de Geofísica Instituto de AstronomiaGeofísica e Ciências Atmosféricas da Universidade de São PauloRua do Matão1226-Cidade UniversitáriaSão Paulo 05508-090Brazil Institut de Physique du Globe de Paris Universitéde ParisCNRSParisFrance Géosciences Montpellier Universitéde MontpellierCNRSUniversitédes AntillesMontpellierFrance Instituto de Geociências Universidade de São PauloRua do Lago562-Cidade UniversitáriaSão Paulo 05508-080Brazil Instituto de Geociências e Engenharias Universidade Federal do Sul e Sudeste do Pará–UNIFESSPAFolha 17Quadra 04Lote especialNova MarabáMarabáPará68505-080Brazil Research School of Earth Sciences The Australian National University142 Mills RoadCanberraACT 2601Australia Applied Isotope Research Group Departamento de GeologiaEscola de MinasUniversidade Federal de Ouro PretoRua Diogo de Vasconcelos12235400-000 Ouro PretoMGBrazil

despite representing one of the largest cratons on Earth,the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events have obscured initial *** this study,we investigated the sedimentary archives of the Carajás Basin to unravel the early geological evolution of the southeastern Amazonia *** Carajás Basin contains sedimentary rocks that were deposited throughout a long period spanning more than one billion years from the Mesoarchean to the *** oldest archives preserved in this basin consist of a few ca.3.6 Ga detrital zircon grains showing that the geological roots of the Amazonia Craton were already formed by the *** the Paleoarchean or the early Mesoarchean(large and rigid enough to sustain the formation and preservation of the Rio Novo Group greenstone ***,during the Neoarchean,at ca.2.7 Ga,the southeastern Amazonia Craton witnessed the emplacement of the Parauapebas large Igneous Province(LIP)that probably covered a large part of the craton and was associated with the deposition of some of the world largest iron *** emplacement of this LIP immediately preceded a period of continental extension that formed a rift infilled first by iron formations followed by terrigenous *** major change of sedimentary regime might have been controlled by the regional tectonic evolution of the Amazonia Craton and its emergence above *** the Paleoproterozoic,at ca.2.1 Ga,the Rio fresco Group,consisting of terrigenous sediments from the interior of the Amazonia Craton,was deposited in the Carajás *** that time,the Amazonian lithosphere could have either underwent thermal subsidence forming a large intracratonic basin or could have been deformed by long wavelength flexures that induced the formation of basins and swells throughout the craton under the influence of

关键词： Carajás Basin Chemical Abrasion–la-ICP-MS analyses Age distribution comparison Parauapebas large Igneous Province Transamazonian orogeny

Satellite Integration into 5G:deep Reinforcement Learning for Network Selection

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Machine Intelligence Research 2022年第2期19卷 127-137页

作者： Emanuele de Santis Alessandro Giuseppi Antonio Pietrabissa Michael Capponi francesco delli Priscoli department of Computer Control and Management Engineering“Antonio Ruberti”University of Rome La SapienzaRome 00185Italy

This paper proposes a deep-Q-network(DQN) controller for network selection and adaptive resource allocation in heterogeneous networks, developed on the ground of a Markov decision process(MDP) model of the problem. Network selection is an enabling technology for multi-connectivity, one of the core functionalities of 5G. for this reason, the present work considers a realistic network model that takes into account path-loss models and intra-RAT(radio access technology) interference. Numerical simulations validate the proposed approach and show the improvements achieved in terms of connection acceptance, resource allocation, and load *** particular, the DQN algorithm has been tested against classic reinforcement learning one and other baseline approaches.

关键词： Network selection HetNet deep reinforcement learning deep-Q-network(DQN) 5G communications

Isometry Groups of Some Dunwoody Manifolds

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Algebra Colloquium 2016年第1期23卷 117-128页

作者： f. Spaggiari A.I. Telloni Dipartimento di Matematica Universit& di Modena e Reggio E. Via Campi 213/B 41100 Modena Italy

Dunwoody manifolds are an interesting class of closed connected orientable 3-manifolds, which are defined by means of Heegaard diagrams having a rotational symmetry. They are proved to be cyclic coverings of lens spaces （possibly S3） branched over （1, 1）-knots. Here we study the Dunwoody manifolds which are cyclic coverings of the 3-sphere branched over two specified families of Montesinos knots. Then we determine the Dunwoody parameters for such knots and the isometry groups for the considered manifolds in the hyperbolic case. A list of volumes for some hyperbolic Dunwoody manifolds completes the paper.

关键词： Dunwoody manifold Montesinos knot branched covering isometry group

describing failure in geomaterials using second-order work approach

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Water Science and Engineering 2015年第2期8卷 89-95页

作者： franois Nicot félix Darve Institut de Recherche en Sciences et Technologies de l'Environnement et de l'Agriculture(IRSTEA) Erosion Torrentielle Neige et Avalanches (ETNA)Geomechanics GroupGrenoble 38402 France Université Joseph fourier (UJf)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS) Laboratoire SolsSolides Structures et RisquesGrenoble 38041 France

Geomaterials are known to be non-associated materials. Granular soils therefore exhibit a variety of failure modes, with diffuse or localized kinematical patterns. In fact, the notion of failure itself can be confusing with regard to granular soils, because it is not associated with an obvious phenomenology. In this study, we built a proper framework, using the second-order work theory, to describe some failure modes in geomaterials based on energy conservation. The occurrence of failure is defined by an abrupt increase in kinetic energy. The increase in kinetic energy from an equilibrium state, under incremental loading, is shown to be equal to the difference between the external second-order work,involving the external loading parameters, and the internal second-order work, involving the constitutive properties of the material. When a stress limit state is reached, a certain stress component passes through a maximum value and then may decrease. Under such a condition, if a certain additional external loading is applied, the system fails, sharply increasing the strain rate. The internal stress is no longer able to balance the external stress, leading to a dynamic response of the specimen. As an illustration, the theoretical framework was applied to the well-known undrained triaxial test for loose soils. The influence of the loading control mode was clearly highlighted. It is shown that the plastic limit theory appears to be a particular case of this more general second-order work theory. When the plastic limit condition is met, the internal second-order work is nil. A class of incremental external loadings causes the kinetic energy to increase dramatically, leading to the sudden collapse of the specimen, as observed in laboratory.

关键词： failure in geomaterials Undrained triaxial loading path Second-order work Kinetic energy Plastic limit condition Control parameter

基于PageRank算法及Mplus因子分析探讨杨霓芝教授诊治IgA肾病规律

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世界科学技术-中医药现代化 2024年第3期26卷 581-590页

作者：卢家言张腊胡晓璇凌曦淘于浩天梁紫越卢佐宸侯海晶卢富华杨霓芝广州中医药大学第二临床医学院广州510006 广东省中医院/广州中医药大学第二附属医院广州510120 广州中医药大学公共卫生与管理学院广州510006 粤港澳中医药与免疫疾病研究联合实验室广州510120

目的本研究旨在多层次分析名老中医诊治IgA肾病的临床经验,为传承中医肾病名医经验提供方法参考。方法采集并标准化广东省中医院杨霓芝教授门诊在2010—2020年期间诊治IgA肾病患者的医案数据,并将患者分为尿血组、尿浊组及肾衰组。利用f... 详细信息

目的本研究旨在多层次分析名老中医诊治IgA肾病的临床经验,为传承中医肾病名医经验提供方法参考。方法采集并标准化广东省中医院杨霓芝教授门诊在2010—2020年期间诊治IgA肾病患者的医案数据,并将患者分为尿血组、尿浊组及肾衰组。利用fangNet平台进行PageRank算法计算药物THScore得到不同亚组IgA肾病核心药物。通过Python(SciPy包、Clusterheatmap包)可视化证型分布规律及相应用药规律,应用Mplus软件使用加权最小二乘估计法及斜交旋转GEOMIN法进行药物处方探索性及验证性因子分析。结果总共纳入145例IgA肾病患者,共548诊次。其中尿血组54例、尿浊组51例及肾衰组40例。基本证型有9种,含气虚证(91.79%)、血瘀证(77.01%)、湿热证(66.06%)及阴虚证(38.69%)等。总队列核心药物24种,尿血组23种,尿浊组21种,肾衰组16种,主要为益气补阳药、滋阴养血药、活血祛瘀药、清热凉血药等。IgA肾病辨证用药规律(Z-Score>0.5且Pf1(菟丝子、山茱萸、黄芪);f2(白茅根、小蓟、茜草);f3(女贞子、墨旱莲、太子参);f4(泽兰、桃仁)。结论本研究通过应用PageRank算法及Mplus因子分析,分组分析杨霓芝教授诊治IgA肾病经验,明确以“气虚血瘀、湿热阴虚”为核心证型,“益气活血、清热养阴”为核心治法的IgA肾病岭南中医诊治心得,为传承名医经验提供方法参考,促进中医药的开发利用。

关键词：因子分析 PageRank算法 IgA肾病名老中医经验