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Effects of Welding Procedure on Corrosion Resistance and Hydrogen Embrittlement of Supermartensitic Stainless Steel Deposits

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Journal of Iron and Steel Research International 2013年第12期20卷 124-132页

作者： Zappa sebastián Surian Estela Svoboda Hernán Research Secretariat Faculty of EngineeringNational University of Lomas de Zamora DEYTEMA-Development and Technology of Materials Centre Regional Faculty San NicolásNational Technological University Materials and Structures Laboratory INTECINFaculty of EngineeringNational University of Buenos Aires CONICET-National Scientific and Technical Research Council

The effects of shielding gas and post weld heat treatment on the pitting resistance, stress corrosion crack- ing and hydrogen embrittlement of supermartensitic stainless steel deposits were studied. Two all-weld-metal test coupons were prepared using a metal-cored wire under Ar＋ 5% He and Ar＋18%CO2 gas shielding mixtures. Solubi- lizing and solubilizing plus double tempering heat treatments were done with the objective of achieving different mi crostructural results, The samples welded under Ar＋5% He showed higher pitting corrosion resistance, for all post weld heat treatments, than those welded under Ar＋18% CO2. The different post weld heat treatments generated higher susceptibility to this corrosion mechanism. None of the samples presented signs of stress corrosion cracking, but in those subjected to the heat treatment, grain boundary selective attack was observed, on the surfaces of all the samples studied. The samples with highest hardness were more susceptible to hydrogen damage, thereby leading to reduced tensile strength on this condition.

关键词： supermartensitic stainless steel shielding gas post weld heat treatment corrosion hydrogen embrittle ment

Contemporaneous assembly of Western Gondwana and final Rodinia break-up:Implications for the supercontinent cycle

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Geoscience Frontiers 2017年第6期8卷 1431-1445页

作者： sebastián Oriolo Pedro Oyhantcabal Klaus Wemmer Siegfried Siegesmund Geoscience Center Georg-August-Universitat GottingenGoldschmidtstrae 337077 GottingenGermany Departamento de Geología Facultad de CienciasUniversidad de la RepúblicaMontevideoUruguay

Geological,geochronological and isotopic data are integrated in order to present a revised model for the Neoproterozoic evolution of Western *** the classical geodynamic scenario assumed for the period 800-700 Ma is related to Rodinia break-up and the consequent opening of major oceanic basins,a significantly different tectonic evolution can be inferred for most Western Gondwana *** cratons occupied a marginal position in the southern hemisphere with respect to Rodinia and recorded subduction with back-arc extension,island arc development and limited formation of oceanic crust in internal *** period was thus characterized by increased crustal growth in Western Gondwana,resulting from addition of juvenile continental crust along convergent *** contrast,crustal reworking and metacratonization were dominant during the subsequent assembly of *** Rio de la Plata,Congo-Sao Francisco,West African and Amazonian cratons collided at ca.630-600 Ma along the West Gondwana *** events overlap in time with the onset of the opening of the Iapetus Ocean at ca.610-600 Ma,which gave rise to the separation of Baltica,Laurentia and Amazonia and resulted from the final Rodinia *** East African/Antarctic Orogen recorded the subsequent amalgamation of Western and Eastern Gondwana after ca.580 Ma,contemporaneously with the beginning of subduction in the Terra Australis Orogen along the southern Gondwana ***,the Kalahari Craton was lately incorporated during the Late Ediacaran-Early *** proposed Gondwana evolution rules out the existence of Pannotia,as the final Gondwana amalgamation postdates latest connections between Laurentia and ***,a combination of introversion and extroversion is proposed for the assembly of *** contemporaneous record of final Rodinia break-up and Gondwana assembly has major implications for the supercontinent cycle,as supercontinent amalgamation and break-

关键词： Brasiliano-Pan-African Orogeny Neoproterozoic Collisional tectonics Pannotia Metacratonization Introversion-extroversion

Sailboat navigation control system based on spiking neural networks

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Control Theory and Technology 2023年第4期21卷 489-504页

作者： Nelson Santiago Giraldo sebastián Isaza Ricardo Andrés Velásquez Department of Electronics and Telecommunications Engineering University of Antioquia67 stMedellin050010AntioquiaColombia

In this paper,we presented the development of a navigation control system for a sailboat based on spiking neural networks(SNN).Our inspiration for this choice of network lies in their potential to achieve fast and low-energy computing on specialized *** train our system,we use the modulated spike time-dependent plasticity reinforcement learning rule and a simulation environment based on the BindsNET library and USVSim *** objective was to develop a spiking neural network-based control systems that can learn policies allowing sailboats to navigate between two points by following a straight line or performing tacking and gybing strategies,depending on the sailing scenario *** presented the mathematical definition of the problem,the operation scheme of the simulation environment,the spiking neural network controllers,and the control strategy *** a result,we obtained 425 SNN-based controllers that completed the proposed navigation task,indicating that the simulation environment and the implemented control strategy work ***,we compare the behavior of our best controller with other algorithms and present some possible strategies to improve its performance.

关键词： Sailboat Control Spiking neuron Reinforcement learning BindsNet USVSim

The importance of grain and cut-off size in shaping tree beta diversity along an elevational gradient in the northwest of Colombia

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Forest Ecosystems 2020年第1期7卷 14-25页

作者： Johanna Andrea Martínez-Villa sebastián González-Caro álvaro Duque Departamento de Ciencias Forestales Universidad Nacional de Colombia sede MedellínCra.65#59a-110MedellínColombia Département des Sciences Biologiques Universitédu QuébecàMontréal141Avenue du Président-KennedyMontrealCanada

Background:Species turnover(β-diversity)along elevational gradients is one of the most important concepts in plant ***,there is a lack of consensus about the main driving mechanisms of treeβ-diversity at local scales in very diverse ecosystems(e.g.,Andean mountains),as well as how the sampling effect can alterβ-diversity ***,it has been hypothesized that patterns of change inβ-diversity at local scales along elevational gradients are driven by sampling effects stemming from differences in the size of the species pool rather than by underlying community assembly ***,we aim to evaluate the relative extent to which sampling effects,such as species pool size,grain size,and tree size cut-off,determine species sorting,and thus,the variability ofβ-diversity at local scales along elevational gradients in the northwest of ***:Using 151-ha permanent plots spread out along a 3000m elevational gradient,we used standardizedβ-deviation to assess the extent to which either sampling effects or the community assembly mechanisms determine the changes in species composition at local ***β-deviation was measured as the difference between the observed and nullβ-diversity divided by the standard deviation of the nullβ-*** found that the magnitude of change in localβ-deviation along the elevational gradient was significant and dependent on the employed spatial grain size and tree size ***,β-deviation increased with elevation in all sampling designs,which suggests that underlying community assembly mechanisms play a key role in shaping localβ-diversity along the elevational ***:Our findings suggest that grain size enlargement and the inclusion of trees with small diameters will improve our ability to quantify the extent to which the community assembly mechanisms shape patterns ofβ-diversity along elevational ***,we emphasize the scale-dependent nature of the assessment o

关键词： Andean forests Null models Species pool Species sorting Sampling effect

Study of polygalacturonase production by an Antarctic yeast and obtention of dragon fruit juice by maceration at mild temperature

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Food Bioscience 2022年第5期49卷 893-903页

作者： Brenda Bezus Juan Carlos Contreras Esquivel sebasti´an Cavalitto Ivana Cavello Centro de Investigaci´on y Desarrollo en Fermentaciones Industriales(CINDEFI UNLPCCT-La PlataCONICET)Calle 47 y 115B1900ASHLa PlataProvincia de Buenos AiresArgentina Laboratory of Applied Glycobiotechnology Academic Group of Food Science and TechnologySchool of ChemistryUniversidad Autonoma de CoahuilaUnidad SaltilloSaltillo2528CoahuilaMexico

The objectives of the present survey were to study the production and the biochemical characterization of an enzymatic cold-active extract with polygalacturonase activity,to perform a first insight into its possible application in fruit-juice obtention process,and to use this juice for food products *** enzymatic extract was produced by the Antarctic yeast Mrakia *** January 7,2016 in a bioreactor with citric pectin as *** polygalacturonase activity showed optimum conditions for reaction at 45◦C and pH *** activity was stable until 40◦C but deactivated at higher *** by Hg+2 suggested the presence of a thiol-dependent enzyme.A high-molecular polygalacturonase was detected in an SDS-PAGE and zymography ***-products were observed by thin-layer chromatography and suggested the endo-mode of *** enzymatic extract had some accessory enzymes,such as pectin methylesterase,β-glucosidase,cellulase and *** a first insight into the potential use of this enzymatic extract for fruit maceration at mild temperatures,red and white dragon fruits were selected as *** 23◦C,juice yields of 15%-23%higher than control were obtained after treatments,with a decrease of remanent solid of 25%-35%.The color of red dragon fruit juice increased with enzymatic *** balls that were prepared with the juices demonstrated a hardness of~10 *** compression force of low-calorie sugar gels was 3.8 *** work provided a complete study of the production,characterization,application and food product production using a new cold-active polygalacturonase extract of Antarctic origin.

关键词： Antarctic enzymes Cold active pectinases Mrakia sp Hylocereus monacanthus Hylocereus undatus

Multipotent mesenchymal stromal cells:A promisingstrategy to manage alcoholic liver disease

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World Journal of Gastroenterology 2016年第1期22卷 24-36页

作者： Fernando Ezquer Flavia Bruna sebastián Calligaris Paulette Conget Marcelo Ezquer Centro de Medicina Regenerativa Facultad de MedicinaClínica Alemana-Universidad del DesarrolloSantiago 7710162Chile

Chronic alcohol consumption is a major cause of liver *** term alcoholic liver disease(ALD)refers to a spectrum of mild to severe disorders including steatosis,steatohepatitis,cirrhosis,and hepatocellular *** limited therapeutic options,stem cell therapy offers significant potential for these *** this article,we review the pathophysiologic features of ALD and the therapeutic mechanisms of multipotent mesenchymal stromal cells,also referred to as mesenchymal stem cells(MSCs),based on their potential to differentiate into hepatocytes,their immunomodulatory properties,their potential to promote residual hepatocyte regeneration,and their capacity to inhibit hepatic stellate *** perfect match between ALD pathogenesis and MSC therapeutic mechanisms,together with encouraging,available preclinical data,allow us to support the notion that MSC transplantation is a promising therapeutic strategy to manage ALD onset and progression.

关键词： Alcoholic liver disease Cellular therapy Alcoholic steatohepatitis Hepatic function recovery Mesenchymal stem cells

Circular RNAs in colorectal cancer:Possible roles in regulation of cancer cells

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World Journal of Gastrointestinal Oncology 2017年第2期9卷 62-69页

作者： María Isabel Taborda sebastián Ramírez Giuliano Bernal Laboratory of Molecular and Cell Biology of Cancer(Cancer Lab) Department of Biomedical SciencesFaculty of MedicineUniversidad Católica del NorteCoquimbo 1781421Chile

Colorectal cancer(CRC) is the third most commonly diagnosed cancer in the world and the fourth principal cause of cancer deaths worldwide. Currently, there is a lack of low cost and noninvasive screening tests for CRC, becoming a serious health problem. In this context, a potential biomarker for the early detection of CRC has recently gained attention. Circular RNAs(circ RNA), a re-discovered, abundant RNA specie, is a type of noncoding covalent closed RNAs formed from both exonic and intronic sequences. These circular molecules are widely expressed in cells, exceeding the abundance of the traditional linear m RNA transcript. They can regulate gene expression, acting as real sponges for mi RNAs and also regulate alternative splicing or act as transcriptional factors and inclusive encoding for proteins. However, little is known about circ RNA and its relationship with CRC. In this review, we focus on the biogenesis, function and role of these circ RNAs in relation to CRC, including their potential as a new biomarker.

关键词： Circular RNA Colorectal cancer Gene regulation CircRNA Non-coding RNAs Long non-coding RNA Circularization

Omics-based biomarkers as useful tools in metabolic dysfunctionassociated steatotic liver disease clinical practice:How far are we?

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World Journal of Gastroenterology 2024年第14期30卷 1982-1989页

作者： Julieta Trinks María F Mascardi Adrián Gadano sebastián Marciano Instituto de Medicina Traslacional e Ingeniería Biomédica-Consejo Nacional de Investigaciones Científicas y Técnicas-Instituto Universitario del Hospital Italiano-Hospital Italiano de Buenos aires Ciudad Autónoma de Buenos Aires C1199ACLArgentina Consejo Nacional de Investigaciones Científicas y Técnicas Ciudad Autónoma de Buenos Aires C1425FQBArgentina Liver Unit Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina Department of Research Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina

Unmet needs exist in metabolic dysfunction-associated steatotic liver disease(MASLD)risk *** ability to identify patients with MASLD with advanced fibrosis and at higher risk for adverse outcomes is still *** novel biomarkers could represent a meaningful improvement to current risk *** this aim,omics technologies have revolutionized the process of MASLD biomarker discovery over the past *** the research in this field is thriving,much of the publication has been haphazard,often using single-omics data and specimen sets of convenience,with many identified candidate biomarkers but lacking clinical validation and *** we incorporate these biomarkers to direct patients’management,it should be considered that the roadmap for translating a newly discovered omics-based signature to an actual,analytically valid test useful in MASLD clinical practice is rigorous and,therefore,not easily *** article presents an overview of this area’s current state,the conceivable opportunities and challenges of omics-based laboratory diagnostics,and a roadmap for improving MASLD biomarker research.

关键词： Metabolic dysfunction-associated steatotic liver disease Non-alcoholic steatohepatitis Biomarker Risk stratification Omics

The Asian Lineage of Zika Virus: Transmission and Evolution in Asia and the Americas

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Virologica Sinica 2019年第1期34卷 1-8页

作者： Tao Hu Juan Li Michael J.Carr sebastián Duchêne Weifeng Shi Key Laboratory of Etiology and Epidemiology of Emerging Infectious Diseases in Universities of Shandong Taishan Medical College Global Station for Zoonosis Control Global Institution for Collaborative Research and Education (GI-CoRE)Hokkaido University National Virus Reference Laboratory School of MedicineUniversity College Dublin Department of Biochemistry and Molecular Biology Bio21 Molecular Science and Biotechnology InstituteUniversity of Melbourne

Since first isolation in 1947 from the Zika forest in Uganda, Zika virus(ZIKV) has been principally known as a benign agent associated with sporadic human infections in a restricted number of African countries. However, during 2015–2016,an Asian lineage of ZIKV caused an unprecedentedly large outbreak in the Americas and sizeable numbers of exported cases across the globe. In this review, we critically appraise the recent advances in molecular epidemiological studies of ZIKV performed to date, and we highlight the pivotal role played by genomic surveillance in elucidating the origins,dissemination and evolution of the Asian lineage of ZIKV in Asia and in the Americas.

关键词： Zika virus(ZIKV) Asian lineage Transmission Evolution Re