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Journal of Earth Science and Engineering 2014年第6期4卷 372-377页

作者： Clara P. Pena-Venegas Acosta luis Eduardo Verschoor Gerard Logreira-Buitrago Camilo esteban Agudelo Edwin Terra Preta Program Wageningen University Wageningen 6700 The Netherlands Instituto Amazonico de lnvestigaciones Cientificas Sinchi Leticia 910001 Amazonas Colombia

Mining is encroaching upon Protected Areas and Indigenous Reserves in the Colombian Amazon. In the Middle Caqueta region small-scale, illegal gold mining is eroding riverbanks, affecting water quality, and jeopardizing the livelihoods of indigenous peoples. In addition, mining also threatens the integrity of pre-Columbian anthropogenic soils (terra preta) created between 500 years to 2,000 years B. P. on the bluffs of the Caqueta River. These soils are the only, non-flooded fertile soils present in the region, and as such are important for local indigenous communities. In Colombia, there is little knowledge about Terra Preta soils. This work assesses the present and potential dangers artisanal mining has for terra preta soils and other natural resources that are central to indigenous peoples" food security. Results posit that more knowledge is needed about the way terra preta soils are related to the livelihoods of indigenous people so that informed policy decisions can be made about the desirability of mining in the region.

关键词：哥伦比亚粮食安全中东地区自然资源土著人人为土矿业威胁

Optimized Convolutional Neural Network Models for Skin Lesion Classification

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Computers, Materials & Continua 2022年第2期70卷 2131-2148页

作者： Juan Pablo Villa-Pulgarin Anderson Alberto Ruales-Torres Daniel Arias-GarzónMario Alejandro Bravo-Ortiz Harold Brayan Arteaga-Arteaga Alejandro Mora-RubioJesus Alejandro Alzate-Grisales esteban Mercado-Ruiz M.Hassaballah Simon Orozco-Arias Oscar Cardona-Morales Reinel Tabares-Soto Department of Electronics and Automation Universidad Autónoma deManizalesManizales170001Colombia SEDMATEC Corporación Universitaria Autónoma de Nari駉Pasto520002Colombia Department of Computer Science Faculty of Computers and InformationSouth Valley UniversityQena83523Egypt Department of Computer Science Universidad Autónoma de ManizalesManizales170001Colombia Department of Systems and Informatics Universidad de CaldasManizales170001Colombia

Skin cancer is one of themost severe diseases,andmedical imaging is among themain tools for cancer *** images provide information on the evolutionary stage,size,and location of tumor *** paper focuses on the classification of skin lesion images considering a framework of four experiments to analyze the classification performance of Convolutional Neural Networks(CNNs)in distinguishing different skin *** CNNs are based on transfer learning,taking advantage of ImageNet ***,in each experiment,different workflow stages are tested,including data augmentation and fine-tuning *** CNN models based on DenseNet-201,Inception-ResNet-V2,and Inception-V3 are proposed and compared using the HAM10000 *** results obtained by the three models demonstrate accuracies of 98%,97%,and 96%,***,the best model is tested on the ISIC 2019 dataset showing an accuracy of 93%.The proposed methodology using CNN represents a helpful tool to accurately diagnose skin cancer disease.

关键词： Deep learning skin lesion convolutional neural network data augmentation transfer learning

Does a Country/Region's Economic Status Affect Its Universities' Presence in International Rankings?

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Journal of Data and Information Science 2019年第2期4卷 56-78页

作者： esteban Fernandez Tuesta Carlos Garcia-Zorita Rosario Romera Ayllon Elias Sanz-Casado Escola de Artes Ciencias e HumanidadesUniversidade de Sao PauloBrazil Department of Library Science and Documentation Carlos III University of MadridSpain Laboratory of Metric Studies on Information(LEMI) Carlos III University of MadridSpain Research Institute for Higher Education and Science(INAECU) MadridSpain Associated Unit IFS(CSIC)-LEMI(UC3M) Carlos III University of MadridSpain Department of Statistics Carlos III University of MadridSpain

Purpose: Study how economic parameters affect positions in the Academic Ranking of World Universities' top 500 published by the Shanghai Jiao Tong University Graduate School of Education in countries/regions with listed higher education institutions. Design/methodology/approach: The methodology used capitalises on the multi-variate characteristics of the data analysed. The multi-colinearity problem posed is solved by running principal components prior to regression analysis, using both classical(OLS) and robust(Huber and Tukey) methods. Findings: Our results revealed that countries/regions with long ranking traditions are highly competitive. Findings also showed that some countries/regions such as Germany, United Kingdom, Canada, and Italy, had a larger number of universities in the top positions than predicted by the regression model. In contrast, for Japan, a country where social and economic performance is high, the number of ARWU universities projected by the model was much larger than the actual figure. In much the same vein, countries/regions that invest heavily in education, such as Japan and Denmark, had lower than expected *** limitations: Using data from only one ranking is a limitation of this study, but the methodology used could be useful to other global rankings. Practical implications: The results provide good insights for policy makers. They indicate the existence of a relationship between research output and the number of universities per million inhabitants. Countries/regions, which have historically prioritised higher education, exhibited highest values for indicators that compose the rankings methodology; furthermore,minimum increase in welfare indicators could exhibited significant rises in the presence of their universities on the ***/value: This study is well defined and the result answers important questions about characteristics of countries/regions and their higher education system.

关键词： Academic Ranking of World Universities Socio-economic indicators Regression analysis

Quasispecies dynamics in main core epitopes of hepatitis B virus by ultra-deep-pyrosequencing

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World Journal of Gastroenterology 2012年第42期18卷 6096-6105页

作者： Maria Homs Maria Buti David Tabernero josep Quer Alex Sanchez Noelia Corral Rafael esteban Francisco Rodriguez-Frias Network Medical Research Center Hepatic and Digestive Diseases(CIBERehd)Institute of Health Carlos Ⅲ08036 BarcelonaSpain Department of Biochemistry Vall d'Hebron HospitalAutonomous University of Barcelona08035 BarcelonaSpain Department of Hepatology Vall d' Hebron HospitalAutonomous University of Barcelona08035 BarcelonaSpain Statistics and Bioinformatics Unit Research InstituteVall d'Hebron Hospital08035 BarcelonaSpain

AIM:To investigate the variability of the main immunodominant motifs of hepatitis B virus(HBV) core gene by ultra-deep-pyrosequencing(UDPS).METHODS:Four samples(2 genotype A and 2 genotype D) from 4 treatment-na ve patients were assessed for baseline *** additional samples from one patient(patient 4,genotype D) were selected for analysis:one sample corresponded to a 36-mo treatment-free period from baseline and the other to the time of viral breakthrough after 18 mo of lamivudine *** HBV region analyzed covered amino acids 40 to 95 of the core gene,and included the two main epitopic regions,Th50-69 and *** was carried out in the Genome Sequencer FLX system(454 Life Sciences,Roche).After computer filtering of UDPS data based on a Poisson statistical model,122 813 sequences were *** most conserved position detected by UDPS was analyzed by site-directed mutagenesis and evaluated in cell ***:Positions with highest variability rates were mainly located in the main core epitopes,confirming their role as immune-stimulating *** addition,the distribution of variability showed a relationship with HBV *** 1(genotype A) presented the lowest variability rates and patient 2(genotype A) had 3 codons with variability higher than 1%.Patient 3 and 4(both genotype D) presented 5 and 8 codons with variability higher than 1%,*** median baseline frequencies showed that genotype A samples had higher variability in epitopic positions than in the other positions analyzed,approaching significance(P = 0.07,sample 1 and P = 0.05,sample 2).In contrast,there were no significant differences in variability between the epitopic and other positions in genotype D ***,patient 1 presented a completely mutated motif from amino acid 64 to 67(E 64 LMT 67),which is commonly recognized by T helper ***,the variability observed in all 4 patients was particularly associated with the E 64 LMT 67 mo

关键词：肝炎病毒抗原表位焦磷酸测序准种 B型超深乙肝表面抗原位置分析

New real-time-PCR method to identify single point mutations in hepatitis C virus

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World Journal of Gastroenterology 2016年第43期22卷 9604-9612页

作者： Qian Chen Irene Belmonte Maria Buti Leonardo Nieto Damir Garcia-Cehic josep Gregori Celia Perales Laura Ordeig Meritxell Llorens Maria Eugenia Soria Rafael esteban Juan Ignacio esteban Francisco Rodriguez-Frias josep Quer Liver Unit Internal Medicine Lab. Malalties Hepàtiques Vall d’Hebron Institut Recerca-Hospital Universitari Vall d’ Hebron08035 Barcelona Spain Centro de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas Instituto de Salud Carlos Ⅲ28029 madrid Spain Liver Pathology Unit Departments of Biochemistry and Microbiology Hospital Universitari Vall d’Hebron Autonomous University of Barcelona 08035 Bareelona Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas del Instituto de Salud Carlos Ⅲ 28029 Madrid Spain Universitat Autònoma de Barcelona 08193 Bareelona Spain

AIM To develop a fast, low-cost diagnostic strategy to identify single point mutations in highly variable genomes such as hepatitis C virus(HCV).METHODS In patients with HCV infection, resistance-associated amino acid substitutions within the viral quasispecies prior to therapy can confer decreased susceptibility to direct-acting antiviral agents and lead to treatment failure and virological relapse. One such naturally occurring mutation is the Q80 K substitution in the HCV-NS3 protease gene, which confers resistance to PI inhibitors, particularly simeprevir. Low-cost, highly sensitive techniques enabling routine detection of these single point mutations would be useful to identify patients at a risk of treatment failure. Light Cycler methods, based on real-time PCR with sequencespecific probe hybridization, have been implemented in most diagnostic laboratories. However, this technique cannot identify single point mutations in highly variable genetic environments, such as the HCV genome. To circumvent this problem, we developed a new method to homogenize all nucleotides present in a region except the point mutation of interest. RESULTS Using nucleotide-specific probes Q, K, and R substitutions at position 80 were clearly identified at a sensitivity of 10%(mutations present at a frequency of at least 10% were detected). The technique was successfully applied to identify the Q80 K substitution in 240 HCV G1 serum samples, with performance comparable to that of direct Sanger sequencing, the current standard procedure for this purpose. The new method was then validated in a Catalonian population of 202 HCV G1-infected individuals. Q80 K was detected in 14.6% of G1 a patients and 0% of G1 b in our setting. CONCLUSION A fast, low-cost diagnostic strategy based on real-time PCR and fluorescence resonance energy transfer probe melting curve analysis has been successfully developed to identify single point mutations in highly variable genomes such as hepatitis C virus. This

关键词：丙肝病毒联系抵抗的氨基酸替换便宜测试单个点的变化 Q80K

紫茎泽兰入侵前后根部蜡样芽孢杆菌含量比较及其对化感物质处理的响应

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生物安全学报 2022年第1期31卷 27-33页

作者：赵云鹏杨子豪徐刚 esteban Rodríguez-Leyva 杨国庆扬州大学园艺与植物保护学院江苏扬州225009 Posgrado en Fitosanidad Entomología y AcarologíaColegio de PostgraduadosTexcocoMexico

【目的】比较紫茎泽兰入侵地种群根部有益菌蜡样芽孢杆菌含量与原产地种群的差异,及其对化感物质的响应,为揭示紫茎泽兰与有益菌互作在入侵前后的变化及其机制提供参考。【方法】分别以紫茎泽兰原产地墨西哥的3个种群(M1、M2、M3)和入... 详细信息

【目的】比较紫茎泽兰入侵地种群根部有益菌蜡样芽孢杆菌含量与原产地种群的差异,及其对化感物质的响应,为揭示紫茎泽兰与有益菌互作在入侵前后的变化及其机制提供参考。【方法】分别以紫茎泽兰原产地墨西哥的3个种群(M1、M2、M3)和入侵地云南的3个种群(C1、C2、C3)为材料,采用同质园试验方法和蜡样芽孢杆菌分子定量的技术,检测原产地和入侵地紫茎泽兰种群植株根部(根系、根际土壤)蜡样芽孢杆菌的含量;使用不同种群紫茎泽兰植株叶片淋溶液和根系分泌液处理入侵地土壤,检测化感物质对土壤中蜡样芽孢杆菌含量的影响。【结果】紫茎泽兰入侵地种群根系蜡样芽孢杆菌含量高于原产地种群,其中入侵地种群C2的含量比原产地种群M1高1172%;在根际土壤中,2年生紫茎泽兰入侵地3个种群的蜡样芽孢杆菌含量显著高于原产地种群M1和M3。紫茎泽兰叶片淋溶液和根系分泌液处理均促进了土壤蜡样芽孢杆菌含量增加,入侵地种群叶片淋溶液处理的土壤的蜡样芽孢杆菌增加量高于原产地种群,根系分泌液处理的后期测定中也如此。【结论】与原产地相比,紫茎泽兰入侵后,根系与根际土壤蜡样芽孢杆菌含量均有所增加,增强了有益菌对入侵地种群的正反馈效应。

关键词：紫茎泽兰蜡样芽孢杆菌化感物质入侵

Taking advantage of the potential of mesenchymal stromal cells in liver regeneration:Cells and extracellular vesicles as therapeutic strategies

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World Journal of Gastroenterology 2018年第23期24卷 2427-2440页

作者： esteban Juan Fiore Luciana María Domínguez Juan Bayo Mariana Gabriela García Guillermo Daniel Mazzolini Laboratory of Gene Therapy Instituto de Investigaciones en Medicina TraslacionalCONICET-Universidad Austral

Cell-based therapies for acute and chronic liver diseases are under continuous progress. Mesenchymal stem/stromal cells(MSCs) are multipotent cells able to migrate selectively to damaged tissue and contribute to its healing and regeneration. The MSC pro-regenerative effect occurs due to their immunomodulatory capacity and their ability to produce factors that promote cell protection and survival. Likewise,it has been observed that part of their paracrine effect is mediated by MSC-derived extracellular vesicles(EVs). EVs contain proteins,lipids and nucleic acids(DNA,m RNA,mi RNA,lnc RNA) from the cell of origin,allowing for intercellular communication. Recently,different studies have demonstrated that MSC-derived EVs could reproduce,at least in part,the biological effects obtained by MSCbased therapies. Moreover,due to EVs' stability for long periods of time and easy isolation methods they have become a therapeutic option to MSCs treatments. This review summarizes the latest results achieved in clinical trials using MSCs as cell therapy for liver regeneration,the role of EVs in liver physiopathology and the potential of MSC-derived EVs as intercellular mediators and therapeutic tools in liver diseases.

关键词： Mesenchymal stem cells Extracellular vesicles Cirrhosis Liver Acute damage Regeneration

Direct conversion of human fibroblasts into retinal pigment epithelium-like cells by defined factors

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Protein & Cell 2014年第1期5卷 48-58页

作者： Kejing Zhang Guang-Hui Liu Fei Yi Nuria Montserrat Tomoaki Hishida Concepcion Rodriguez esteban Juan Carlos Izpisua Belmonte] Gene Expression Laboratory Salk Institute for Biological Studies 10010 North Torrey Pines Road La Jolla CA 92037 USA National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Department of Molecular and Cellular Physiology Stanford University School of Medicine 265 Campus Drive StanfordCA 94305 USA Center for Regenerative Medicine in Barcelona Dr. Aiguader 88 08003 Barcelona Spain Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine (CIBER-BBN) BarcelonaSpain

The generation of functional retinal pigment epithelium （RPE） is of great therapeutic interest to the field of regenerative medicine and may provide possible cures for retinal degenerative diseases, including age-related macular degeneration （AMD）. Although RPE cells can be produced from either embryonic stem cells or induced pluripotent stem cells, direct cell reprogramming driven by lineage-determining transcription factors provides an immediate route to their generation. By monitoring a human RPE specific Bestl：：GFP reporter, we report the conversion of human fibroblasts into RPE lineage using defined sets of transcription factors. We found that Bestl：：GFP positive cells formed colonies and exhibited morphological and molecular features of early stage RPE cells. Moreover, they were able to obtain pigmen- tation upon activation of Retinoic acid （RA） and Sonic Hedgehog （SHH） signaling pathways. Our study not only established an ideal platform to investigate the tran- scriptional network regulating the RPE cell fate deter- mination, but also provided an alternative strategy to generate functional RPE cells that complement the useof pluripotent stem cells for disease modeling, drug screening, and cell therapy of retinal degeneration.

关键词： retinal pigment epithelium fibroblasts,direct conversion

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基于神经网络方法的单晶孔洞行为模型

基于神经网络方法的单晶孔洞行为模型

Influence of temperature and salinity on hydrodynamic forces

中国力学大会-2021+1

作者：郭河杰凌超 esteban P.Busso 李晨锋李东风哈尔滨工业大学(深圳)理学院斯旺西大学Zienkiewicz工程计算中心

研究背景对于韧性断裂单晶孔洞行为在对孔洞层面的研究通常需要使用代表性体元作为研究工具,并且单晶孔洞的行为依赖于一系列的加载参数和微结构变量。然而,使用这种基于有限元方法的韧性断裂分析既费时又耗钱。此外,在整个应力状态和...

研究背景对于韧性断裂单晶孔洞行为在对孔洞层面的研究通常需要使用代表性体元作为研究工具,并且单晶孔洞的行为依赖于一系列的加载参数和微结构变量。然而,使用这种基于有限元方法的韧性断裂分析既费时又耗钱。此外,在整个应力状态和晶体取向范围内,在宏观或构件水平上进行大规模计算仍然具有挑战性。

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Journal of Ocean Engineering and Science 2016年第4期1卷 325-336页

作者： A.Escobar V.Negro J.S.López-Gutiérrez M.D.esteban Technical University of Madrid C/Profesor Aranguren S/N28040 MadridSpain

The purpose of this study is to introduce an innovative approach to offshore engineering so as to take variations in sea temperature and salinity into account in the calculation of hydrodynamic *** this in mind,a thorough critical analysis of the influence of sea temperature and salinity on hydrodynamic forces on piles like those used nowadays in offshore wind farms will be carried *** influence on hydrodynamic forces occurs through a change in water density and viscosity due to temperature and salinity ***,the aim here is to observe whether models currently used to estimate wave forces on piles are valid for different ranges of sea temperature and salinity apart from observing the limit when diffraction or nonlinear effects arise combining both effects with the magnitude of the pile ***,specific software has been developed to simulate equations in fluid mechanics taking into account nonlinear and diffraction *** software enables wave produced forces on a cylinder supported on the sea bed to be *** study includes observations on the calculation model’s sensitivity as to a variation in the cylinder’s diameter,on the one hand and,on the other,as to temperature and salinity *** software will enable an iterative calculation to be made for finding out the shape the pressure wave caused when a wave passes over will have for different pile diameters and water with different temperature and salinity.

关键词： Sea temperature Salinity Hydrodynamic forces Wave action Offshore wind farms