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Effect of the initial EcAP passes on crystal texture and residual stresses of 5083 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 801-808页

作者： L.Romero-Reséndiz A.Flores-Rivera I.A.Figueroa c.Braham c.reyes.ruiz I.Alfonso G.González Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.de México 04510México Procédés et Ingénierie en Mécanique et Matériaux Arts et MétiersParis 75013France Departamento de Diseño y Manufactura Facultad de IngenieríaUniversidad Nacional Autónoma de MéxicoPIIT Apodaca 66629México Instituto de Investigaciones en Materiales Unidad MoreliaUniversidad Nacional Autónoma de MéxicoMorelia 58190México

To produce a highly refined microstructure,several metals or alloys have been processed via equal-channel angular pressing(EcAP).In this work,the mechanical and microstructural changes of the 5083 aluminum alloy in H11 condition after processed by two EcAP passes were *** EcAP H13 steel die with an inner angle(α)of 120°and outer curvature(β)of 20°was *** microstructural changes were associated with the loss of texture *** morphologies of the Mg2Si andα-Al(Mn,Fe)Si precipitates for the sample at the initial condition were similar to those subjected to two EcAP *** peak broadening measured by X-ray diffraction revealed an increment of both grain refinement and *** the second extrusion pass,the hardness increased by 62%compared with the initial ***,the heterogeneous hardness behavior was compatible with a highly localized dislocation *** two EcAP passes,shear parallel bands were observed to be at nearly 45°to the extrusion *** evaluation of first-order residual stress as a function of the depth of the analyzed sample displayed compressive or tensile values,depending on the measured *** the plastic deformation applied,the first and second-order residual stresses exhibited significant ***-Hall plots showed positive slopes,indicating an increment in the microstrain.

关键词： aluminum alloy equal-channel angular pressing texture microstructure residual stress

The Beauty of Being a Variant： H2A.Z and the SWR1 complex in Plants

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Molecular Plant 2009年第4期2卷 565-577页

作者： Rosana March-Diaz Jose c. reyes Andalusian center for Molecular Biology and Regenerative Medicine (cABIMER) CSIC Americo Vespucio s/n E-41092 Sevilla Spain

Numerous studies have shown that the nucleosome is a dynamic structure that strongly influences gene expression. Dynamism concerns different nucleosomal characteristics, including position, posttranslational modifications, and histone composition. Thus, within the nucleosome, canonical histones can be exchanged by histone variant proteins with specific functions--a process known as ‘histone replacement＇. The histone variant H2A.Z has an important function in transcription and, during the last few years, its role in plant development and immune response has become evident. compiling genetic and biochemical studies from several laboratories has revealed that plants contain a multiprotein complex, similar to the SWR1/SRcAP complex from yeast and animals, involved in H2A.Z deposition. Despite intense research in different organisms, the mechanism by which H2A.Z influences transcription is still unknown. However, recent results from Arabidopsis have shown a strong inverse correlation between H2A.Z and DNA methylation, suggesting that H2A.Z might protect genes from silencing.

关键词： chromatin structure and remodeling epigenetics gene regulation floral induction.

Human cD4 ＋ effector T lymphocytes generated upon TcR engagement with self-peptides respond defectively to IL-7 in their transition to memory cells

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cellular & Molecular Immunology 2013年第3期10卷 261-274页

作者： Gabriela Gonzalez-Perez Norma c Segovia Amaranta Rivas-carvalho Diana P reyes Honorio Torres-Aguilar Sergio R Aguilar-ruiz claudine Irles Gloria Soldevila carmen Sainchez-Torres 1Department of Molecular Biomedicine Centre de Investigacion y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN) Mexico City Mexico Department of Physiology Facultad de Medicina Mexico City Mexico Department of Immunology Institute de Investigaciones Biomedicas Universidad Nacional Autonoma de Mexico (UNAM) Mexico City Mexico

The peripheral repertoire of cD4＋ T lymphocytes contains autoreactive cells that remain tolerant through several mechanisms. However, nonspecific cD4＋ T cells can be activated in physiological conditions as in the course of an ongoing immune response, and their outcome is not yet fully understood. Here, we investigate the fate of human naive cD4＋ lymphocytes activated by dendritic cells （Dcs） presenting endogenous self-peptides in comparison with lymphocytes involved in alloresponses. We generated memory cells （Tmem） from primary effectors activated with mature autologous Dcs plus interleukin （IL）-2 （Tmauto）, simulating the circumstances of an active immune response, or allogeneic Dcs （Tmallo）. Tmem were generated from effector cells that were rested in the absence of antigenic stimuli, with or without IL-7. Tmem were less activated than effectors （demonstrated by cD25 downregulation） particularly with IL-7, suggesting that this cytokine may favour the transition to quiescence. Tmauto and TmaHo showed an effector memory phenotype, and responded similarly to polyclonal and antigen-specific stimuli. Biochemically, IL-7-treated Tma^o were closely related to conventional memory lymphocytes based on Erk-l/2 activation, whereas Tmauto were more similar to effectors. Autologous effectors exhibited lower responses to IL-7 than allogeneic cells, which were reflected in their reduced proliferation and higher cell death. This was not related to IL-7 receptor expression but rather to signalling deficiencies, according to STAT5 activation These results suggest that ineffective responses to IL-7 could impair the transition to memory cells of naive cD4＋ T lymphocytes recognizing self-peptides in the setting of strong costimulation.

关键词： human cD4+ T cells IL-7 memory self-peptides

Bofedal response to climate variability, local management, and water extraction: A case study of chucuyo, Northern chile

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Journal of Mountain Science 2022年第1期19卷 241-252页

作者： URIBE-ÁLVAREZ Monserrat c PRIETO Manuel MESEGUER-ruiz Oliver Departamento de ciencias Históricas y Geográficas Universidad de TarapacáArica 1010069Chile Departamento de ciencias Históricas y Geográficas Universidad de TarapacáIquique 1101783Chile

Andean high-altitude wetlands are important ecosystems that serve a range of socialecological functions. In the Andes, bofedales, a specific type of peat-producing wetland, are essential for the sustainability of mountain ecosystems and indigenous pastoralist communities. The chucuyo bofedal in northern chile is affected by climatic variability and water extraction for agricultural uses via the Lauca canal. Herders in the local community also actively manage this wetland according to their traditional ecological knowledge to ensure permanent fodder for their animals. In this article, we analyze the annual behavior of the chucuyo bofedal after the wet season. Based on precipitation data, extracted water flows, vegetation vigor from satellite images, and an ethnographic approach, we determined that the bofedal’s productivity was negatively correlated with the amount of precipitation and positively correlated with the surface area of the wetland. However, water extraction via the Lauca channel had no significant relationship with either surface area or vegetation vigor. We identify community practices and traditional ecological knowledge as key elements in the maintenance of these ecosystems. This situation is critical in the context of an aging population and the current pattern of migration out of the region to urban areas. The results provide substantial empirical evidence for future decision-making regarding the conservation of these ecosystems.

关键词： Atacama Bofedales Indigenous people Lauca canal Normalized Difference Vegetation Index

Application of formal languages in polynomial transformations of instances between NP-complete problems

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Journal of Zhejiang University-Science c(computers and Electronics) 2013年第8期14卷 623-633页

作者： Jorge A. ruiz-VANOYE Joaquín PREZ-ORTEGA Rodolfo A. PAZOS RANGEL Ocotlán DíAZ-PARRA Héctor J. FRAIRE-HUAcUJA Juan FRAUSTO-SOLíS Gerardo reyes-SALGADO Laura cRUZ-reyes DAcI Universidad Autónoma del Carmen computer Science Centro Nacional de Investigación y Desarrollo Tecnológico Systems and computer Science Instituto Tecnológico de Ciudad Madero Informatics Universidad Politécnica del Estado de Morelos computer Science Instituto Tecnológico de Cuautla

We propose the usage of formal languages for expressing instances of NP-complete problems for their application in polynomial transformations. The proposed approach, which consists of using formal language theory for polynomial transformations, is more robust, more practical, and faster to apply to real problems than the theory of polynomial transformations. In this paper we propose a methodology for transforming instances between NP-complete problems, which differs from Garey and Johnson's. Unlike most transformations which are used for proving that a problem is NP-complete based on the NP-completeness of another problem, the proposed approach is intended for extrapolating some known characteristics, phenomena, or behaviors from a problem A to another problem B. This extrapolation could be useful for predicting the performance of an algorithm for solving B based on its known performance for problem A, or for taking an algorithm that solves A and adapting it to solve B.

关键词： Formal languages Polynomial transformations NP-completeness

Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 921-935页

作者： A.colaço P.Alves costa c.Ferreira c.Parente J.Fernandez-ruiz cONSTRUcT-FEUP University of PortoRua Dr.Roberto Frias4200-465 PortoPortugal University of La coruña Department of Civil EngineeringCampus de Elviña 15071La CoruñaSpain

Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the *** pile driving is an interesting and viable solution from economic and technical points of ***,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately *** this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear *** the complexity of the problem,an experimental test site was developed and fully *** experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile *** comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile *** experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models.

关键词： pile driving ground-borne vibrations numerical modeling experimental validation

Angle-to-angle and spur-to-spur distance analysis with high-resolution optical coherence tomography

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Eye and Vision 2020年第1期7卷 399-411页

作者： Robert Montés-Micó Pedro Tañá-Rivero Salvador Aguilar-córcoles María ruiz-Santos María Dolores Rodríguez-carrillo Ramón ruiz-Mesa Oftalvist Alicante and Jerez de la FronteraAlicanteSpain University of Valencia ValenciaSpain

Background:To measure angle-to-angle(ATA)and spur-to-spur(STS)distances along six meridians using highresolution swept-source optical coherence tomography(SS-OcT)and to compare those values with horizontal white-to-white(WTW)***:68 eyes from 68 patients were quantitatively assessed with the Anterion SS-OcT(Heidelberg Engineering,Heidelberg,Germany).ATA and STS distances were measured with the SS-OcT’s B-Scan in six cross-sectional images corresponding to the vertical(6-12 o’clock),1-7 o’clock,2-8 o’clock,horizontal(3-9 o’clock),4-10 o’clock and 5-11 o’clock *** was measured horizontally with the device’s infrared camera.A Pearson correlation analysis was carried out to compare ATA and STS distances with ***:The largest values were found for the vertical meridian and the shortest for the 2-8 o’clock meridian,both for ATA and STS *** statistically significant differences were found between WTW,ATA and STS along the horizontal meridian(p>0.1).However,ATA and STS showed statistically significant differences elsewhere,except for the horizontal and the 2-8 o’clock meridians(p>0.05).Moreover,we found that ATA and STS varied significantly depending on the meridian being assessed,except for ATA at 4-10 versus 3-9 o’clock and for STS at 4-10 versus 3-9 o’clock and at 3-9 versus 2-8 o’clock(p>0.1).R^(2) values ranged from 0.49 to 0.75 for ATA and STS at the different meridians,showing the best correlation at 3-9 o’clock meridian(0.64 and 0.75,respectively)and the worst at 6-12 o’clock meridian(R^(2)=0.49 for both ATA and STS).conclusions:ATA and STS distances vary radially,thus showing that the anterior chamber is vertically ***,it is advisable to measure these two distances along the meridian to be used.

关键词： Angle-to-angle Spur-to-spur White-to-white Optical coherence tomography Swept-source Fourier domain

characterization of two Achromobacter xylosoxidans isolates from patients with pertussis-like symptoms

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 465-468页

作者： Fiorella Orellana-Peralta Michelle Jacinto Maria J.Pons cláudia Gomes carlos Bada Isabel reyes Juana del Valle Mendoza Joaquim ruiz Facultad de ciencias de la Salud.Universidad Peruana de ciencias Aplicadas-LiPc LimaPeru ISGlobal Barcelona Ctr.Int.Health Res.(CRESIB)Hospital Clinic-Universitat de Barcelona Hospital de Emergencias Pediatricas.Lima Peru Instituto de Investigacion Nutrirional LimaPeru

Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance ***:Nasopharyngeal swabs from 2 children under 1 year of age with clinical suspicion of pertussis were analyzed by culture and ***:Two Achromobaeter xylosoxidans A8,closely related to Bordetella *** recovered from 2 patients diagnosed of pertussis,both carrying the ptxA gene and IS418 the pertussis toxin encoding ***,antibiotic susceptibility was evaluated by disk-diffusion method and by ***:Although more detailed studies are needed,the present data highlight the possibility that Achromobaeter *** related Bordetella pertussis microorganisms and not covered under the vaccine umbrella,might also result in cases of whooping *** further surveillance is necessary to determine the extension and relevance of their pathogenic role in order to discriminate their real public health implication.

关键词： Achromobacter xylosoxidans Bordetella pertussis

Hairless canary seeds (Phalaris canariensis L.) as a potential source of antioxidant, antihypertensive, antidiabetic, and antiobesity biopeptides

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Food Production, Processing and Nutrition 2021年第1期3卷 80-91页

作者： U.c.Urbizo-reyes J.E.Aguilar-Toalá A.M.Liceaga Protein chemistry and Bioactive Peptides Laboratory Department of Food SciencePurdue University745 Agriculture Mall DriveWest LafayetteIN 47907USA

Rising consumer concerns with synthetic drugs to treat non-communicable diseases(NcDs)have promoted a shift towards using natural biological active constituents that offer similar health *** canary seed(Phalaris canariensis L)is an emerging crop traditionally used in Mexico to treat *** liberated during simulated digestion of canary seed protein are believed to be responsible for their biological activity;however,no studies have shown the effect of controlled protein hydrolysis using commercial proteases on canary seed protein’s biological ***,this study aimed to explore the in vitro antihypertensive,antidiabetic,and anti-obesity activity of canary seed peptides derived from proteolysis with Alcalase®.Protein fractions were primarily composed of prolamins(54.07±1.8%),glutelins(32.19±3.18%),globulins(5.97±0.52%)and albumins(5.97±0.52%).Thections showed the highest inhibition capacity(pconverting enzyme(Ic50=0.028–0.032 mg/mL)lipase(Ic50=2.15–2.27 mg/mL),α-glucosidase(Ic50=0.82–1.15 mg/mL),and dipeptidyl-peptidase-IV(Ic50=1.27–1.60 mg/mL).Additionally,these peptide fractions showed high antioxidant activity against DPPH(134.22–150.66μmol TE/mg)and ABTS(520.92–813.33μmol TE/mg).These results provide an insight into the potential development of functional foods using commercial enzymatic hydrolysis of canary seed proteins for treating hypertension,type-2 diabetes,and obesity.

关键词： canary seeds Bioactive peptides Anti-obesity activity Antihypertensive activity Antidiabetic activity