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New insights into petrogenesis of Miocene magmatism associated with porphyry copper deposits of the Andean Pampean flat slab,Argentina

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Geoscience Frontiers 2018年第5期9卷 1565-1576页

作者： Silvia I.Carrasquero Nora A.Rubinstein Anabel L.R.Gómez Massimo Chiaradia Dénis Fontignie victor a.valencia Facultad de Ciencias Naturales y Museo Universidad Nacional de La Plata Instituto de Geociencias básicas aplicadas y ambientales de Buenos Aires (IgeBA) Departamento de Ciencias Geológicas Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos-CONICET Department of Earth Sciences University of Geneva School of Earth and Environmental Sciences Faculty Washington State University

The Paramillos de Uspallata mining district located in the backarc region of the Pampean flat-slab segment(28°-33°S) features porphyry-type deposits genetically associated with Middle Miocene volcanics. This mineralizing magmatism comprising hydrothermally altered(sodic-calcic, potassic and phyllic alteration) subvolcanic and pyroclastic rocks of andesite-basaltic andesite and dacite-rhyolite composition with a typical arc signature, represents the eastward broadening of the Farellones arc by ~17 Ma. Its geochemistry also reveals a residual mineralogy of amphibole ± garnet with limited plagioclase fractionation resulting in an adakitic signal; however, according to the isotopic data collected in our study, the contributions of MASH(melting-assimilation-storage-homogenization) processes in the acquisition of this signal cannot be *** the broadening of the Farellones arc and its residual mineralogy e typical of relatively deep magmatic chambers e are consistent with a slab shallowing and outcoming crustal thickening *** tectonic scenario could be interpreted as a result of an early effect of the Juan Fernandez Ridge collision that was further to the north by ~17 Ma. Our findings suggest that magmas were fertile for porphyry type deposits during the early stages of the slab shallowing.

关键词： Porphyry copper deposits

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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor V.Chizhikov Igor Y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

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The transition from backarc extension to Andean growth:Insights from geochronologic,sedimentologic,and structural studies of Mesozoic and Cenozoic sedimentary and volcanic rocks in south-central Chile(36°S)

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Geoscience Frontiers 2024年第5期15卷 93-117页

作者： Alfonso Encinas Nicolás Henríquez Daniel Castro Darío Orts Diego Kietzmann Franco Iovino Paulo Vásquez Andrés Folguera victor valencia Facundo Fuentes Departamento de Ciencias de la Tierra Facultad de Ciencias QuímicasUniversidad de ConcepciónVíctor Lamas 1290Concepción 4030000Chile Universidad Nacional de Río Negro.Instituto de Investigación en Paleobiología y Geología.General Roca Río NegroArgentina Instituto de Investigación en Paleobiología y Geología(IIPG).CONICET.Av.J.A.Roca 1242 8332 General RocaRío NegroArgentina Universidad de Buenos Aires Facultad de Ciencias Exactas y NaturalesDepartamento de Ciencias GeológicasCiudad UniversitariaPabellón ⅡIntendente Güiraldes 2160C1428EHA Ciudad Autónoma de Buenos AiresArgentina CONICET-Universidad de Buenos Aires Instituto de Geociencias BásicasAmbientales y Aplicadas de Buenos Aires(IGeBA)Ciudad UniversitariaPabellón ⅡIntendente Güiraldes 2160C1428EHA Ciudad Autónoma de Buenos AiresArgentina Instituto de Estudios Andinos“Don Pablo Groeber”(IDEAN) CONICET-Universidad de Buenos AiresBuenos AiresArgentina Facultad de Ciencias Exactas y Naturales Universidad de Buenos AiresBuenos AiresArgentina Washington State University School of the EnvironmentPullmanUSA Yacimientos Petrolíferos Fiscales(YPF)S.A. Buenos AiresArgentina

Many studies propose a significant shift in the tectonic and paleogeographic evolution of the Andes in south-central Chile and Argentina during the Late *** has been proposed that the preceding Jurassic-Early Cretaceous extensional regime that resulted in a low-relief volcanic arc and the backarc Neuquén basin came to an end,giving way to shortening and Andean growth from the Late Cretaceous ***,there are disagreements regarding the timing and nature of this transition to Andean *** address these issues,we conducted geochronologic(U-Pb and^(40)Ar/&(39)Ar),sedimentologic,and structural studies on Mesozoic-Cenozoic sedimentary and volcanic rocks in the Río Maule area(Principal Cordillera,Chile,36°S).From our findings and prior analyses,we propose the following tectono-stratigraphic evolution of the region.(1)Marine deposition of the Tithonian-Hauterivian Baños del Flaco Formation took place in an extensional backarc basin.(2)After a~40 Myr hiatus,fluvial deposits of the Colimapu Formation and volcanic rocks of the Plan de los Yeuques Formation accumulated during the *** the Colimapu Formation displays evidence of syndepositional shortening,the Plan de los Yeuques Formation exhibits synextensional growth *** to other studies,our results suggest that the Chilean part of the Principal Cordillera was largely a zone of active deposition rather than an elevated fold-thrust belt during the Late *** propose that sedimentation occurred within a series of relatively stable intermontane subbasins generated by shortening,followed by extension.(3)After a~20 Myr hiatus,middle Eocene to early Miocene(Lutetian-Aquitanian)accumulation of a thick succession of andesitic lavas and minor clastic sediments of the Abanico Formation occurred in an intraarc extensional basin.(4)Finally,major shortening and uplift of previously deposited Mesozoic-Cenozoic rocks took place throughout the *** phase constitu

关键词： Andes South-central Chile Backarc basin Foreland basin Fold-thrust belt

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“What is a Sociologist Doing Here?”An Unconventional People-Centered Approach to Improve Warning Implementation in the Sendai Framework for Disaster Risk Reduction

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International Journal of Disaster Risk Science 2020年第2期11卷 218-229页

作者： victor Marchezini Cemaden–National Early Warning and Monitoring Center of Natural Disasters Distrito de Eug8nio de Melo 12.247-016Sao Jose dos CamposSPBrazil Doctorate Program on Earth System Science National Institute for Space ResearchSao Jose dos CamposBrazil Programa de Pós-Gradua??o em Desastres Naturais ICT/Unesp-CemadenSao Jose dos Campos.Brazil

The Sendai Framework for Disaster Risk Reduction 2015–2030 recommends several actions for early warning systems(EWSs). However, there is a lack of information about their means of implementation. This article used institutional ethnography to analyze the 2012–2018 implementation of a national warning system in Brazil. The challenges related to daily activities, and the interdisciplinary works in the four axes of EWSs towards multi-hazard and people-centered approaches are discussed. This national experience is then discussed in the light of the global challenges of EWSs considering two main issues:(1) experiences of implementation and barriers related to people-centered warning systems;and(2)types of national/regional warning systems and hazards/threats that are being monitored as an important input for multi-hazard approaches. There are few multi-hazard warning systems in place and EWSs are focused on hydrometeorological hazards, mainly related to floods. The Sendai Framework needs to improve access to data and information, identify views from the frontline, consider political threats and vulnerabilities, and find ways to talk about disaster risk creation processes at a larger scale.

关键词： Risk governance Interdisciplinary research People-centered warning systems

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Cryotic climate conditions and their eventual implication in the high-mountain surface of the Nevado de Toluca volcano, Mexico

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Journal of Mountain Science 2021年第9期18卷 2273-2286页

作者： SOTO victor Facultad de Ciencias Biológicas y Agropecuarias Universidad VeracruzanaPoza Rica-Tuxpan 92870México

The state of the cryosphere in tropical regions is of great importance because the temperature around the glaciers, permafrost and snow cover always fluctuates near the melting point. These thermal conditions and their high sensitivity to climate change cause the accelerated disappearance of these elements;therefore, it is important to know the climatic factors that regulate them, as well as the physical characteristics of each cryospheric element. Unlike glaciers, permafrost and snow cover have not been widely studied. In recent decades, the study of the glacial and periglacial environment has been carried out in intertropical mountains. However, despite the altitude of their relief and the frequent occurrence of snowfall in tropical high mountains, the conditions that determine such events have been barely analyzed;and in the case of Mexico, the volume of snowfall and its thickness have not been quantified either, as well as their corresponding duration. Consequently, this work is aimed to analyze the temperature and precipitation conditions that determine the snowfall at the higher part of the Nevado de Toluca volcano;at the same time, the conditions of the cryotic climate and their possible implication on the surface are studied. The analysis of data from 1965 to 2016, using frequency statistics, allowed to realize that snowfall occurs with low intensity, its accumulation being less than 10 cm thick and 10 mm of snow water equivalent, which causes the snowpack to stay only a few weeks on average. At the same time, it was determined that there is a significant increase in the number of freeze-thaw cycles. Therefore, due to the climate conditions and their influence on the mountain surface, it is probable that the bedrock is subject to a greater gelifraction dynamics, and the unconsolidated soil surface increases;the combination of the above could cause a greater geomorphological dynamic over time, particularly due to debris flows, and by water and wind erosion of

关键词： Air temperature Cryotic conditions High-mountain climatology Periglacial geomorphology Snow precipitation

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Transnational Dialogues on Interdisciplinary Approaches for Advancing People-Centered Warning Systems

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International Journal of Disaster Risk Science 2023年第5期14卷 868-872页

作者： victor Marchezini Cemaden–National Early Warning and Monitoring Centre of Natural Disasters São Josédos Campos12.247-016Brazil Natural Hazards Center Institute of Behavioral ScienceUniversity of Colorado BoulderBoulderCO80309USA

The United Nations Office for Disaster Risk Reduction and the World Meteorological Organization launched in 2022 the executive plan of the world program "Early Warning Systems for All" to be implemented from 2023 to *** program champions an investment of USD 3.1 billion into the four pillars of warning systems and calls for multi-hazard and peoplecentered warning systems(PCWS).However,there is a scientific gap concerning interdisciplinary approaches to promoting *** by the call for action of "Early Warning Systems for All" and warning research gaps on the lack of interdisciplinarity,a workshop series "Interdisciplinary Approaches for Advancing People-Centered Warning Systems" was held in early *** short article shares the preliminary findings and recommendations of this research,which involved a transnational virtual dialogue between one scientific organization in Brazil and one from the United *** findings and recommendations discussed in three virtual sessions and one collective working paper were centered on three aspects:promoting interdisciplinary integration in research;the need to discuss the characteristics of a PCWS;and promoting problem-and solution-based programs with people to integrate them at all phases of the warning system.

关键词： Capacity building Cooperation Interdisciplinary methods Warning implementation Warning research

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Miscellaneous Rotating Solitary Waves to a Coupled Dispersionless System

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Chinese Physics Letters 2009年第9期26卷 61-64页

作者： Kuetche Kamgang victor Ecole Nationale Superieure Polyteehnique University of Yaounde I PO Box 8390 Cameroon Department of Physics Faculty of Science University of Yaounde I PO Box. 812 Cameroon Higher Teacher's Training College of Maroua University of Maroua P.O. Box. 46 Cameroon The A bdus Salam International Centre for Theoretical Physics P.O. Box 586 Strada Costiera II-34014 Trieste Italy

We investigate the soliton structure of a coupled dispersionless system describing a current-conducting string with infinite length within a magnetic field. Thus, following Hirota＇s method, we unwrap three typical localized waves with nonzero angular momentum depending strongly upon their angular velocities. Illustrating the soliton behavior of these waves, we focus our interests on breather-like waves and depict the elastic scattering amongst such waves.

关键词： sea surface nonliear interaction numerical method

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Stereodynamics of O（^3P）＋H2 at Scattering Energies of 0.5, 0.75, and 1.0 eV

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Chinese Journal of Chemical Physics 2010年第2期23卷 149-154,I0001页

作者： victor Wei-keh Wu 国立高雄应用科技大学、化学材料工程系高雄80782 胜利者基础研究实验室、比勒费尔德D-33602 德国

Quasiclassical trajectory calculation of the title reaction O（^3P）＋H2→OH＋H at three different scattering energies of 0.5, 0.75, and 1.0 eV on the lowest electronic potential energy surface 1^3A＂ has been done. Distribution P（θr） of polar angles between the relative velocityk of the reactant and rotational angular momentum vector j＇ of the product, distribution P（φr） of the azimuthal as well as dihedral angles correlating k-k＇-j＇, 3-dimensional distri-bution, and polarization-dependent differential cross sections （PDDCSs）dependent upon the scattering angle of the product molecule OH between the relative velocity k of the reactant and k＇ of the product at different scattering energies of 0.5, 0.75, and 1.0 eV are presented and discussed.

关键词： Quasiclassical trajectory calculation Stereodynamics Alignment Rotational angular momentum Polarization-dependent differential cross section O+H2 reaction

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Mathematics of microRNAs: stabilizing gene regulatory networks

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National Science Review 2019年第6期6卷 1189-1190页

作者： victor Ambros Program in Molecular Medicine University of Massachusetts Medical School

Micro RNAs(miRNAs) are fascinating in their versatility. Animal cells express hundreds of distinct micro RNAs, and each micro RNA can regulate hundreds of distinct m RNA ***, in aggregate, the micro RNA compliment of a cell can exert pervasive effects on gene expression. Individual micro RNAs can also be potent determinants of phenotype: The

关键词： RNA stabilizing gene regulatory networks Mathematics of microRNAs

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Processing stages of Gd_2Sr(Al_(1-x)Fe_x)_2O_7 series

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Rare Metals 2014年第1期33卷 47-53页

作者： Ekaterina Tugova victor Gusarov Laboratory of New Inorganic Materials Ioffe Physical Technical Institute of RAS Department of Physical Chemistry St. Petersburg State Institute of Technology Technical University

The continuous series of perovskite-related oxides with the general formula GdzSr（Al1-xFex）207 0 〈 x 〈 1 were prepared by conventional ceramic technology in air. The pro- cessing stages of Gd2Sr（Al1-xFex）207 0 〈 x 〈 1 phases were investigated by means of X-ray powder diffraction （XRD） and scanning electron microscopy （SEM） with the element phase analysis. The three main stages of GdeSr（All_~Fex）aO7 for- marion are pointed out. The analysis of the mutual influence of intermediate compounds on the synthesis of the target solid solutions of complex composition, in particular for Gd2Sr（All-xFex）207 was carried out. It is determined that the closeness of the reactive mixture composition to the composition of individual compounds Gd2SrA1207 or GdaSrFeaO7 is of importance for the realization of a partic- ular way of GdESr（Al1-xFex）207 solid solutions formation. It is shown that at x ,= 0.2 the reversing in scheme of Gd2Sr（Al1-Fex）207 series formation is observed. The formation of the Gd2Sr（Al1-xFex）207 continuous series is indicated by the monotonic dependence of molar unit cell volume on the iron content x.

关键词： Rare-earth metals Oxide materials Solid-state reactions Ceramics X-ray diffraction (XRD) Scanning electron microscopy (SEM)

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