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Iterated Inverse Images of plane Curve Singularities

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2319-2328页

作者： eduardo CASAS-ALVERO Joaquim ROE Departament d＇Algebra i Geometria Universitat de Barcelona Gran Via 585 08007 Barcelona Spain Departament de Matematiques Universitat Autonoma de Barcelona 08193 Bellaterra （Barcelona） Spain

We describe the evolution of certain multiplicities and intersection numbers of plane curve singularities under the iterated action of an analytic morphism.

关键词： plane curve singularity analytic morphism dynamics of intersection

Hydrocarbon distribution along the Soapaga thrust(Eastern Cordillera, Colombia) based on new strategic geochemistry samples

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Acta Geochimica 2022年第3期41卷 335-350页

作者： eduardo A.Rossello Rolando Di primio Departamento de Ciencias Geologicas Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaCONICET-IGEBAPabellon II1428 Buenos AiresArgentina Lundin Energy Norway LysakerNorway

The Colombian Eastern Cordillera constitutes a region with potential for finding hydrocarbon reserves that are still under-explored, despite the existence of oil and tar sand production. The intense tectonic deformation affects the petroleum systems and increases exploration challenges due to the different generation, maturation, and entrapment conditions that they produce. Diverse geochemical analysis conducted on strategic samples determines that these are likely generated by the same anoxic marine source rock type. Two source rock samples we investigated are characterized by very different biomarker signals as compared to the tar sands and oil samples. Both samples are dominated by hopanes as compared to tri-and tetracyclic terpanes, with very low(Tibasosa Formation) to no(Chipaque Formation) extended tricyclic terpanes. The Soapaga Thrust, along which the analyzed samples are located, has exercised first-rate regional structural control of the distribution of hydrocarbons in the studied area. The uplift of their Mesozoic hanging wall produces intense erosion with sediment transport towards the eastern footwall forming the present infill of the Arcabuco basin. The kitchen areas were connected with the shallower entrapment sectors where excellent reservoir levels such as the picacho Formation before the Soapaga Thrust movement. The high degree of biodegradation observed in the picacho Fm. tar sands support early charge before the Soapaga thrust movement, and severe biodegradation following the thrust movement when hydrocarbon supply from the kitchen was interrupted. This work aims to contribute to a better understanding of the geochemical characteristics of the petroleum systems due to the action of the Soapaga Thrust.

关键词： Hydrocarbon geochemistry Soapaga thrust Eastern Cordillera Colombia

H∞position transfer and regulation for floating offshore wind turbines

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Control Theory and Technology 2020年第3期18卷 231-245页

作者： eduardo Eribert ESCOBAR AQUINO Ryozo NAGAMUNE Department of Mechanical Engineering The University of British ColumbiaVancouverBC V671Z4Canada

This paper proposes H∞controller design for platform position transfer and regulation of floating offshore wind *** platform movability of floating wind turbines can be utilized in mitigating the wake effect in the wind farm,thereby maximizing the wind farm's total power capture and *** controller is designed so that aerodynamic force is adjusted to meet the three objectives simultaneously,that is,1)to generate the desired electrical power level,2)to achieve the desired platform position,and 3)to suppress the platform *** acquire sufficient aerodynamic force to move the heavy platform,the pitch-to-stall blade pitching strategy is taken instead of the commonly-used pitch-to-feather *** desired power level is attained by the standard constant-power strategy for the generator torque,while Hstate-feedback control of blade pitch and nacelle yaw angles is adopted for the position regulation and platform oscillation *** constants for the H∞controller design are adjusted to take the trade-off between the position regulation accuracy and the platform motion *** demonstrate the efficiency of the proposed controler,a virtual 5-MW semi-submersible wind turbine is *** results show that the designed H∞controller successfully accomplishes the platform position transfer and regulation as well as the platform oscillation reduction against wind and wave disturbances,and that it outperforms a previously-proposed linear quadratic controller with an integrator.

关键词： Offshore wind farm wind turbine position power regulation disturbance rejection H∞control

High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian peninsula

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Geoscience Frontiers 2020年第5期11卷 1461-1475页

作者： Daniel Castro Martin Souto Maria Isabel Fraga eduardo Garcia-Rodeja Sebastian perez-Diaz Jose Antonio Lopez Saez Xabier pontevedra-pombal Dpto.Botanica Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Edafoloxia e Quimica Agricola Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain Dpto.Geografia Urbanismo y Ordenacion Del TerritorioETS CaminosCanales y PuertosUniversidad de CantabriaSpain GI Arqueobiologia Instituto de HistoriaCCHS–CSICMadridSpain

to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice *** proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface ***:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 AD,1075–665 calibrated years before present[*** Bp]);four corresponding to the Little Ice Age(1345 to 1905 AD;665–105 cal yr Bp);and three corresponding to the last century(1905 to 2000 AD).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier *** Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(Leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet *** LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification ***,four different climate phases were differentiated in this ***-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global *** study provides new information and a detailed chronology of climatic events that will hel

关键词： Last millennium Raised bog plant macrofossil Humification analysis Southwest Europe Climate change

Sperm quality in mice acutely treated with parathion

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Asian Journal of Andrology 2000年第2期2卷 147-150页

作者： Cristian Sobarzo eduardo Bustos-Obregon Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.Faculty of Basic Sciences Catholic University of Temuco and Biology of Reproduction Unit Program of Morphology ICBM Faculty of Medicine University of Chile. Santiage 7 Chile.

Aim: To investigate the toxic effect of a single injection of the organophosphorous agropesticide, parathion, on sper-matogenesis in immature male mice. Methods: Seven-day old mice received a single injection of parathion intraperi-toneally at a dose of 1/3 LD_50. The epididymal sperm count, sperm morphology and chromatin thermal stability wereanalyzed 28 and 50 days after injection. Results: Sperm counts were decreased and teratozoospermia and thermal de-naturation of DNA increased after parathion injection. Sperm parameters were changed to a greater extent in younger an-imals, denoting a higher lability of spermatogenic process at its beginning. The damages could recover a long time afterparathion administration. Conclusion: Organophosphorous agropesticides are testicular toxicants, eliciting reversiblecytotoxic and cytogenetic alterations in germ cells.

关键词： epididymis spermatozoa organophosphorous compounds agropesticides spermatogenesis

Development of a nanostructured filter for pyrolysis wax purification:Effects of particulate filter aids

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particuology 2021年第1期19卷 164-172页

作者： Juliano Missau Daniel Assumpcao Bertuol eduardo Hiromitsu Tanabe Environmental processes Laboratory(LApAM) Chemical Engineering DepartmentFederal University of Santa Maria–UFSMAvenida Roraima 100097105-900Santa MariaRSBrazil

Wax obtained from the pyrolysis of polyethylene waste can contain inorganic contaminants and must be purified before *** evaluated different filter aids(perlite,sand,and rice husk ash)for the filtration of a crude wax and a pyrolysis wax through a filter medium that was coated with nylon 6 nanofibers to improve filtration *** first examined the performance of the filter aids in improving crude wax filtration,with the filtration time,temperature,and pressure held constant at 1 h,170℃,and 2.5 bar,*** wax was then produced by pyrolysis of high-density polyethylene(HDpE)waste in the temperature range 425-475℃.The best filter aid was perlite,which had a filtrate production rate of 5.47×10^(-5)m^(3)/*** highest oily wax yield(87.8%)was achieved at a pyrolysis temperature of 425℃.The assembly comprising the filter medium coated with nylon 6 nanofibers plus perlite as a filter aid was most suitable for removing impurities from the oily wax generated by the HDpE pyrolysis as it achieved a purification efficiency of 99.9%.

关键词： HDpE pyrolysis wax plastic solid waste Nanofiber-coated filter Filter aids Filtration

provenance and drainage system of the Early Cretaceous volcanic detritus in the Himalaya as constrained by detrital zircon geochronology

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Journal of palaeogeography 2015年第1期4卷 85-98页

作者： Xiu-Mian Hu eduardo Garzanti Wei An State Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Department of Earth and Environmental Sciences Università di Milano?BicoccaMilano 20126 Italy

The age range of the major intra-plate volcanic event that affected the northern Indian margin in the Early Cretaceous is here defined precisely by detrital zircon geochronology. U-pb ages of Early Cretaceous detrital zircons found in the Cretaceous to the paleocene sandstones cluster mainly between 142 Ma and 123 Ma in the northern Tethys Himalayan unit, and between 140 Ma and 116 Ma in the southern Tethys Himalayan unit. The youngest and oldest detrital zircons within this group indicate that volcanism in the source areas started in the latest Jurassic and ended by the early Albian. Stratigraphic data indicate that volcaniclastic sedimentation began significantly earlier in southern Tibet （Tithonian） than in Nepal （Valangin- ian）, and considerably later in Spiti and Zanskar （Aptian/AIbian） to the west. This apparent westward migration of magmatism was explained with progressive westward propagation of extensional/transtensional tectonic activity and development of fractures cutting deeply across the Indian continental margin crust. However, detrital zircon geochronology provides no indication of heterochroneity in magmatic activity in the source areas from east to west, and thus lends little support to such a scenario. Westward migration of volcaniclastic sedimentation may thus reflect instead the westward progradation of major drainage systems supplying volcanic detritus sourced from the same volcanic centers in the east. Development of multiple radial drainage away from the domal surface uplift associated with magmatic upwelling, as observed for most large igneous provinces around the world, may also explain why U-pb ages of detrital zircons tend to cluster around 133-132 Ma （the age of the Cornel igneous province） in Tethys Himalayan units, but around 118-117 Ma （the age of the Rajmahal igneous province） in Lesser Himalayan units.

关键词： northern Indian margin Cretaceous Himalayan Orogen volcaniclastic detri-tus drainage system zircon geochronology palaeogeography

A Data Security Framework for Cloud Computing Services

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Computer Systems Science & Engineering 2021年第5期37卷 203-218页

作者： Luis-eduardo Bautista-Villalpando Alain Abran Department of Electronic Systems Autonomous University of AguascalientesAguascalientes20131Mexico Department of Software Engineering and Information Technology ETSUniversity of QuebecMontrealH3C 1K3Canada

Cyberattacks are difficult to prevent because the targeted companies and organizations are often relying on new and fundamentally insecure cloudbased technologies,such as the Internet of *** increasing industry adoption and migration of traditional computing services to the cloud,one of the main challenges in cybersecurity is to provide mechanisms to secure these *** work proposes a Data Security Framework for cloud computing services(CCS)that evaluates and improves CCS data security from a software engineering perspective by evaluating the levels of security within the cloud computing paradigm using engineering methods and techniques applied to *** framework is developed by means of a methodology based on a heuristic theory that incorporates knowledge generated by existing works as well as the experience of their *** paper presents the design details of the framework,which consists of three stages:identification of data security requirements,management of data security risks and evaluation of data security performance in CCS.

关键词： Cloud computing services computer security data security data security requirements data risk data security measurement

phenotypic Variation among and within Three peppers Species(Capsicum)from Mexico

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phyton-International Journal of Experimental Botany 2021年第1期90卷 259-275页

作者： Carlos eduardo Ornelas-Ramírez Sergio Hernández-Verdugo Jesús Enrique Retes-Manjarrez Angel Valdez-Ortiz Antonio pacheco-Olvera Tomás Osuna-Enciso Flor porras Facultad de Agronomía Universidad Autónoma de SinaloaCuliacánSinaloa80000México programa Regional de posgrado en Biotecnología Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de SinaloaCuliacánSinaloa80030México Centro de Investigación en Alimentación y Desarrollo A.C.Unidad Culiacán CuliacánSinaloa80110México

The phenotypic variation and its distribution among species,morphotypes,and among and within populations was estimated in 71 populations pertaining to 15 morphotypes of three domesticated species of Capsicum from *** were made in the states of Sinaloa,Nayarit,Oaxaca,Tabasco,and Yucatán in two agroecosystems:Backyard-garden and *** phenotypic characteristics were analyzed through one-way variance analysis and multivariate analyses of principal components analysis(pCA)and hierarchical clustering using Ward’s *** study was performed in a uniform greenhouse experiment.A high variation was found among and within populations in all the measured *** the total variation,13.0%was distributed among species,27.9%among morphotypes,8.1%among populations,and 51.0%within *** plants grew in a uniform environment,these results indicate that the differences observed among and within species,morphotypes,and populations have a genetic *** and multivariate analyses clearly differentiated morphotypes,suggesting that the category of morphotypes must be used to nominate the infraspecific variation in the domesticated *** principal components analysis identified a total of 15 principal components that contributed to explain the total *** first two components explained 59.64%of the total variation and seven components explained more than 90%of the total *** the measured characteristics,number of seed per fruit,weight of the fruit,width of the fruit,length of the fruit,stem diameter,days to flowering,and height of the plant contributed to component 1 variation,whereas width of the leaf,length of the leaf,and number of locules,number of fruits and number of seeds per plant contributed to component *** hierarchical clustering separated the populations and the morphotypes in two large different *** group consisted of populations collected in monoculture conditions and the oth

关键词： phenotypic variation Capsicum annuum Capsicum chinense Capsicum frutescens morphotype