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Numerical analysis of rapid drawdown: Applications in real cases

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Water Science and Engineering 2016年第3期9卷 175-182页

作者： eduardo E. alonso Nuria M. Pinyol Department of Civil and Environmental Engineering Universitat Politecnica de Catalunya (UPC) Barcelona 08034 Spain Centre Internacional de Metodes Numerics en Enginyeria (CIMNE) Barcelona 08034 Spain

In this study, rapid drawdown scenarios were analyzed by means of numerical examples as well as modeling of real cases with in situ measurements. The aim of the study was to evaluate different approaches available for calculating pore water pressure distributions during and after a drawdown. To do that, a single slope subjected to a drawdown was first analyzed under different calculation alternatives, and numerical results were discussed. Simple methods, such as undrained analysis and pure flow analysis, implicitly assuming a rigid soil skeleton, lead to significant errors in pore water pressure distributions when compared with coupled flow-deformation analysis. A similar analysis was performed for the upstream slope of the Glen Shira Dam, Scotland, and numerical results were compared with field measurements during a controlled drawdown. Field records indicate that classical undrained calculations are conservative but unrealistic. Then, a recent case of a major landslide triggered by a rapid drawdown in a reservoir was interpreted. A key aspect of the case was the correct characterization of permeability of a representative soil profile. This was achieved by combining laboratory test results and a back analysis of pore water pressure time records during a period of reservoir water level fluctuations. The results highlight the difficulty of predicting whether the pore water pressure is overestimated or underestimated when using simplified approaches, and it is concluded that predicting the pore water pressure distribution in a slope after a rapid drawdown requires a coupled flow-deformation analysis in saturated and unsaturated porous media.

关键词： Hydro-mechanical coupling Coupled flow-deformation analysis Numerical analysis Drawdown Landslide Pore water pressure

Proactive reconciliation as a tool for integrating mining and milling operations

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International Journal of Mining Science and Technology 2019年第2期29卷 239-244页

作者： Ana Carolina Chieregati Luiz eduardo campos Pignatari Francis Fernand Pitard Homero Delboni Jr Department of Mining and Petroleum Engineering University of Sao Paulo EDEM Engenharia Mineral Francis Pitard Sampling Consultants

Historically, reconciliation has been viewed as a quality test of model estimates as well as a powerful tool for detecting and correcting problems in all stages of mine operations from resource estimation to metal production. If used correctly, reconciliation helps to better predict the life of mine(LOM), improves the adherence of production plans to the respective budget, and allows for effective control of the mining and milling processes. However, the accuracy of reconciliation results requires that all input data must be generated in accordance with the principles of sampling correctness. Furthermore, complete reconciliation systems can become extremely complex and must be carefully analyzed in order to provide realistic and helpful conclusions. Based on these concepts, this paper presents a successful proactive reconciliation system applied to a copper and gold mine in Brazil for monitoring and integrating mining and milling operations.

关键词： Reconciliation Prognostication Sampling Gold Copper

Robotic surgery for rectal cancer: Current immediate clinical and oncological outcomes

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World Journal of Gastroenterology 2014年第39期20卷 14359-14370页

作者： Sergio eduardo alonso Araujo Victor Edmond Seid Sidney Klajner Department of Gastroenterology University of Sao Paulo Medical School Sao Paulo (SP) 05403-000 Brazil Albert Einstein Hospital Sao Paulo (SP) 05652-901 Brazil

Laparoscopic rectal surgery continues to be a challenging operation associated to a steep learning curve. Robotic surgical systems have dramatically changed minimally invasive surgery. Three-dimensional, magnified and stable view, articulated instruments, and reduction of physiologic tremors leading to superior dexterity and ergonomics. Therefore, robotic platforms could potentially address limitations of laparoscopic rectal surgery. It was aimed at reviewing current literature on short-term clinical and oncological(pathological) outcomes after robotic rectal cancer surgery in comparison with laparoscopic surgery. A systematic review was performed for the period 2002 to 2014. A total of 1776 patients with rectal cancer underwent minimally invasive robotic treatment in 32 studies. After robotic and laparoscopic approach to oncologic rectal surgery, respectively, mean operating time varied from 192-385 min, and from 158-297 min; mean estimated blood loss was between 33 and 283 mL, and between 127 and 300 mL; mean length of stay varied from 4-10 d; and from 6-15 d. Conversion after robotic rectal surgery varied from 0% to 9.4%, and from 0 to 22% after laparoscopy. There was no difference between robotic(0%-41.3%) and laparoscopic(5.5%-29.3%) surgery regarding morbidity and anastomotic complications(respectively, 0%-13.5%, and 0%-11.1%). Regarding immediate oncologic outcomes, respectively among robotic and laparoscopic cases, positive circumferential margins varied from 0% to 7.5%, and from 0% to 8.8%; the mean number of retrieved lymph nodes was between 10 and 20, and between 11 and 21; and the mean distal resection margin was from 0.8 to 4.7 cm, and from 1.9 to 4.5 cm. Robotic rectal cancer surgery is being undertaken by experienced surgeons. However, the quality of the assembled evidence does not support definite conclusions about most studies variables. Robotic rectal cancer surgery is associated to increased costs and operating time. It also seems to be associated

关键词： Surgical procedures Minimally invasive Rectal neoplasms Robotics Colorectal surgery

Behavior of materials for earth and rockfill dams:Perspective from unsaturated soil mechanics

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 1-39页

作者： eduardo E.alonso Rafaela CARDOSO Universidad Politécnica de Cataluña BarcelonaSpain Instituto Superior Técnico LisbonPortugal

The basis of the design of earth and rockfill dams is focused on ensuring the stability of the structure under a set of conditions expected to occur during its *** mechanical and hydraulic conditions must be considered since pore pressures develop during construction,after impoundment and in *** instability phenomena caused by transient flow and internal erosion must be *** prediction of the hydromechanical behavior of traditional and non-traditional materials used in the construction of dams is therefore *** materials used for dam’s construction cover a wide range from clayey materials to *** a broad sense they are compacted materials and therefore unsaturated materials.A summary of the current level of knowledge on the behavior of traditional materials used in the construction of dams is presented in the *** compacted materials(with a significant clay fraction),rockfill and compacted soft rocks are studied with more *** latter are non-traditional *** are analysed because their use,as well as the use of mixtures of soil and rock,is becoming more necessary for sustainability reasons.

关键词： dams unsaturated soil mechanics suction rockfill clayey soil mixture

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工程屏障中的气体迁移(英文)

岩石力学与工程学报 2006年第4期25卷 693-708页

作者： eduardo E. alonso 加泰罗尼亚理工大学(UPC)岩土工程系

建立了高放废物工程屏障体系变形与二相流(偏重于气体迁移)的耦合模型。同时,介绍模型的创新点,在于引入了由变形有关的可变渗透性界面来模拟回填材料和坚硬岩石或混凝土结构之间的关系。压力、应力和体积含水量的计算结果与实测值的对... 详细信息

建立了高放废物工程屏障体系变形与二相流(偏重于气体迁移)的耦合模型。同时,介绍模型的创新点,在于引入了由变形有关的可变渗透性界面来模拟回填材料和坚硬岩石或混凝土结构之间的关系。压力、应力和体积含水量的计算结果与实测值的对比较吻合。研究结果表明:此模型可精确描述在大规模现场试验中的真实过程。

关键词：高放废物含砂膨润士废物处理气体迁移原位试验本构模型反分析

Ni-based catalysts obtained from perovskites oxides for ethanol steam reforming

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燃料化学学报 2018年第11期46卷 1332-1341页

作者： Fabiola Nerina Agüero Jose Antonio alonso Maria Teresa Fernández-Díaz Luis eduardo Cadus Instituto de Investigaciones en Tecnología Química(INTEQUI) UNSL-CONICETAlmirante Brown 14555700 San LuisArgentina Instituto de Ciencia de Materiales de Madrid Consejo Superior de Investigaciones CientíficasCantoblanco28049 MadridSpain Institut Laue-Langevin B.P.156F-38042 Grenoble Cedex 9France

Perovskites as host structures of cations were used in order to generate in situ active and stable catalysts for ethanol steam reforming. For this purpose,La_(1-x)Mg_xAl_(1-y)Ni_yO_3(x = 0.1; y = 0,0.1,0.2,0.3) perovskites were synthetized by the citrate *** segregation is evident for a substitution level higher than 0. 2. The segregation of Ni as NiO generated species interacts with different metal-support after the reduction step. The y = 0.1 catalyst presents the highest H_2 yield value about 85% during reaction time,with low mean values of CH_4 and CO selectivities of 3.4% and 11%,respectively and a low carbon formation. The better performance of y = 0.1 catalyst could be attributed to the minor proportion of segregated phases,thus a controlled expulsion of Ni is successfully reached.

关键词： perovskites catalyst design ethanol steam reforming

3′-UTR of the SARS-CoV-2 genome as a possible source of piRNAs

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Genes & Diseases 2023年第3期10卷 668-670页

作者： María Teresa Hernández-Huerta Laura Pérez-campos Mayoral Carlos Alberto Matias-Cervantes Carlos Romero Díaz Eli Cruz Parada eduardo Pérez-campos Mayoral Rafael Baltiérrez-Hoyos Margarito Martínez Cruz Gabriel Mayoral Andrade eduardo Pérez-campos CONACyT Faculty of Medicine and SurgeryAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 8020Mexico National Technology of Mexico/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico

SARS-CoV-2 is the causal agent of the COVID-19 pandemic. This is a single-stranded RNA beta-coronavirus that is comprised of a 5′ and 3′-untranslated region (UTR) in its non-coding RNA (ncRNA) region. The P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) are ncRNA sequences that bind to transposons and interfere with the translation of new genes. Here, we search for short sequences in the non-coding regions, corresponding to 28 nucleotides (nt). These start from a uracil and have a conserved region of at least 10 nt of homology with the previously reported piRNAs. The aim of this work was to identify piRNA-like sequences in the 3′-UTR of SARS-CoV-2 from the reported Wuhan Patient's genome sequence (GenBank: MN908947.3).

关键词： piRNA sequences piRNAs

Interaction of piRNA-like sequences from the 3′-UTR of SARS-CoV-2 with mRNA regions

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Genes & Diseases 2023年第6期10卷 2282-2284页

作者： Laura Pérez-campos Mayoral María Teresa Hernández-Huerta Carlos Romero Díaz Carlos Alberto Matias-Cervantes eduardo Pérez-campos Mayoral Margarito Martínez Cruz Juan de Dios Ruiz-Rosado Edgar Gustavo Ramos Martínez Marco Antonio Sánchez Medina eduardo Pérez-campos Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico CONACyT Faculty of Medicine and Surgery.Autonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico National Technology of Mexico(TecNM)/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico The Research Institute at Nationwide Children's Hospital Columbus 43205USA Facultad de Química Universidad Nacional Autónoma de MéxicoCoyoacán 04510Mexico

Piwi-interacting RNAs(piRNAs of 26-32 nt in length)regulate gene expression,epigenetics,and transcriptional and post-transcriptional processes.1 In humans,piRNAs are expressed in germline and somatic tissues,and generally have a uracil at the 5'-end(position+1),an adenine at the+10 position,and are 2'-0 methylated at the 3'-end.2 Onice piRNAs form the RNA-induced silencing complex(RISC)with PIWl proteins,they serve as guides to find their complementary sequences of the target mRNA,thus initiating their *** Wuhan patient's genome is approximately 265 nucleotides(nts)in its 3'-UTR;piRNAs-like sequences have been reported in this region.3 Our objective was to search,through bioinformatics,for mRNA sequences that were homologous to the reverse complementary of the previously reported piRNA-like sequences from the 3'-UTR of SARS-Cov-2,3 and identify the possible interaction between them.

关键词： sequences complementary initiating

Old climatically-buffered infertile landscapes(OCBILs):more than harsh habitats,Atlantic Forest inselbergs can be drivers of evolutionary diversity

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Journal of Mountain Science 2022年第9期19卷 2528-2543页

作者： Felipe de CARVALHO ARAÚJO Natália de AGUIAR-campos Cleber Rodrigo de SOUZA eduardo de Paiva PAULA Rubens Manoel dos SANTOS Laboratory of Phytogeography and Evolutionary Ecology Department of Forest SciencesFederal University of LavrasLavrasMinas GeraisBrazil

Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human *** a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in *** recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil *** fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary *** found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water *** inferior inselberg habitats harbor higher lineage diversity than expected by *** strongly predicted evolutionary *** concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.

关键词： Phylogenetic diversity Atlantic Forest Niche conservatism Environmental filters Soil fertility Terrestrial Island