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Improved shape hardening function for bounding surface model for cohesive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 328-337页

作者： andrés Nieto-Leal Victor N.Kaliakin Department of Civil & Environmental Engineering University of Delaware Newark DE 19716 USA Department of Civil Engineering Universidad Militar Nueva Granada Bogotá Colombia

A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one.

关键词： Constitutive model Bounding surface plasticity Shape hardening function Clay

Helicobacter pylori CagA protein polymorphisms and their lack of association with pathogenesis

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World Journal of Gastroenterology 2010年第31期16卷 3936-3943页

作者： Nicole Acosta andrés Quiroga Pilar Delgado María Mercedes Bravo Carlos Jaramillo Molecular Diagnostics and Bioinformatics Laboratory Biological Sciences DepartmentLos Andes University Infectious Agents and Cancer Research Group National Cancer Institute(Colombia)

AIM: To investigate Helicobacter pylori (H. pylori) CagA diversity and to evaluate the association between protein polymorphisms and the occurrence of gastric pathologies. METHODS: One hundred and twenty-two clinical isolates of H. pylori cultured from gastric biopsies obtained from Colombian patients with dyspepsia were included as study material. DNA extracted from isolates was used to determine cagA status, amplifying the C-terminal cagA gene region by polymerase chain reaction. One hundred and six strains with a single amplicon were sequenced and results were used to characterize the 3' variable region of the cagA gene. To establish the number and type of tyrosine phosphorylation motifs Glutamine acid-Proline-Isoleucine-Tyrosine-Alanine (EPI-YA) bioinformatic analysis using Amino Acid Sequence Analyzer-Amino Acid Sequence Analyzer software was conducted. Analysis of the association between the number of EPIYA motifs and the gastric pathology was performed using χ2 test and analysis of the presence of EPIYA-C motifs in relation to the pathology was made by logistic regression odds ratios. Comparisons among EPIYA types found and those reported in GenBank were performed using a proportion test in Statistix Analytical Software version 8.0. RESULTS: After amplification of the 3' of the cagA gene, 106 from 122 isolates presented a single amplicon and 16 showed multiple amplicons. As expected, diversity in the size of the cagA unique fragments among isolates was observed. The 106 strains that presented a single amplicon after 3' cagA amplification came from patients with gastritis (19 patients), atrophic gastritis (21), intestinal metaplasia (26), duodenal ulcer (22) and gastric cancer. DNA sequence analysis showed that the differences in size of 3' cagA unique fragments was attributable to the number of EPIYA motifs: 1.9% had two EPIYA motifs, 62.3% had three, 33.0% had four and 2.8% had five motifs. The majority of tested clinical strains (62.3%) were found to harbor

关键词： Helicobacter pylori CagA-protein polymorphisms Molecular characterization Bioinformatic analysis Pathogenesis Cancer

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高压条件下块体碳纳米管的制备(英文)

新型炭材料 2014年第3期29卷 193-202页

作者： Pamela andr.a Mantey dos Santos Аrea de Ciências Tecnológicas Centro Universitário Franciscano UNIFRA Santa Maria 97010-032 RS Brasil Instituto de Química Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil

分别以高纯碳纳米管(MWCNTs)、未纯化MWCNTs和盐酸纯化MWCNTs为原料,铅(Pb)和石墨(Gr)为压力传递媒介,在4GPa和7.7GPa高压和室温条件下制备块体碳纳米管。其直径约为6nm,呈圆柱形块体。采用拉曼光谱仪、X-射线衍射仪、氮吸附仪和透射电... 详细信息

分别以高纯碳纳米管(MWCNTs)、未纯化MWCNTs和盐酸纯化MWCNTs为原料,铅(Pb)和石墨(Gr)为压力传递媒介,在4GPa和7.7GPa高压和室温条件下制备块体碳纳米管。其直径约为6nm,呈圆柱形块体。采用拉曼光谱仪、X-射线衍射仪、氮吸附仪和透射电镜表征样品。结果表明,含有MgO催化剂杂质的未纯化MWCNTs,以Pb为媒介时,在7.7GPa下可获得最佳压缩样品。高压可引起MWCNTs压缩和剪切应力。Pb容器作为准静压传递媒介可提供更多压缩应力,同时杂质能作为黏结剂,从而有利于得到致密化度较高的MWCNTs。

关键词：碳纳米管高压块体碳纳米管拉曼光谱透射电镜

Soundscape Dynamics at Anuran Reproductive Sites in Pannonian Biogeographical Region：Effects of Road Noise on Vocal Activity

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Asian Herpetological Research 2016年第1期7卷 34-40页

作者： andrás WEIPERTH Ed SMITH Szilvia SIMIGLA Miklòs PUKY Yezhong TANG MTA Centre Jor Ecological Research Danube Research Institute H- 1113 Budapest Karolina ut 29 Hungary Department of Psychology University of Maryland College Park MD 20742 USA Chengdu Institute of Biology Chinese Academy of Sciences # 9 of Section 4 South Renmin Road Chengdu 610041 Sichuan China

The emerging field of soundscape ecology views ecosystems in terms of biophony, geophony and anthrophony. Soundscape ecology considers the effects of sound on fauna, and this research focuses on anuran breeding lek soundscapes. The sensitivity of anuran breeding leks to acoustic disturbances makes breeding leks an important venue for a comparative soundscape study. We made long-term（〉 24 h） sound recordings in three representative wetlands and short-term（〈 30 min） recordings in ten sites in the Pannonian Biogeographical Region of Hungary and around the Hungary and Slovakia border. Long-term soundscapes of the floodplain stretch, where there is relatively minor anthrophonical disturbance, showed an obvious circadian change in sound intensities. The site with moderate sound contamination exhibited a disturbed pattern of circadian sound variation, while the site with heavy traffic noise displayed an apparently random temporal soundscape. At different amphibian breeding sites during mating season, our short-term recordings were dominated by anuran calls, bird songs and wind noises, while insect calls and rain were present to a lesser degree. Our study indicates that vehicle traffic noise is a severe imposition to the natural soundscape, and suggests that soundscape monitoring can provide a reliable and sensitive index of environmental change for both short-term and long-term periods.

关键词： soundscape monitoring anuran breeding site biophony geophony anthrophony

Presence of Fleischer ring and prominent corneal nerves in keratoconus relatives and normal controls

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 922-927页

作者： gnes Kriszt Gergely Losonczy andrs Berta Lili Takcs Department of Ophthalmology University of Debrecen Clinical Center

AIMTo examine the occurrence of commonly known clinical signs of keratoconus (KC), i.e. Fleischer ring, prominent corneal nerves and thinning, among unaffected family members of KC patients and healthy control *** of both eyes of 117 relatives of KC patients having no manifest disease based on videokeratography indices (KC relatives), and 142 controls were used for Pearson correlation and t-test statistics. Correlation of Fleischer ring, prominent corneal nerves and central pachymetry data were tested with each other and with videokeratography indices (KSI, KISA, 3 and 6 mm Fourier asymmetry, and I-S).RESULTSA moderate correlation was found between Fleischer ring and all examined topographical indices. Most important correlation was present with 6 mm Fourier asymmetry, and corneal pachymetry (r=0.272, P<0.001; r=-0.234, P=0.027, respectively). Similar correlations were found with prominent corneal nerves (r=0.234, P<0.001 for 6 mm Fourier asymmetry and r=-0.235, P=0.0265 for pachymetry). KC family members who exhibited Fleischer ring or prominent nerves had thinner and more asymmetric corneas than those without Fleischer ring or prominent corneal nerves (P<0.05 for pachymetry and topographic indices with t-test and Mann-Whitney rank sum test). Though rarely, Fleischer ring and prominent corneal nerves occurred among normal controls, indicating the existence of forme fruste cases in the normal population. Control subjects, who had corneal Fleischer ring or prominent nerves had corneas more similar to KC than other controls (t-test: increased KSI and KISA, P=0.048 and 0.012, respectively).CONCLUSIONIn KC family members and healthy individuals, Fleischer ring and prominent corneal nerves are associated with features of KC and may suggest a possibility of forme fruste KC. Searching for the possible presence of Fleischer ring or prominent nerves on the cornea may help in the decision whether or not to diagnose subclinical KC in

关键词： forme fruste/subclinical keratoconus Fleischer ring corneal nerves corneal thinning videokeratographic indices iatrogenic keratectasia

A novel surface mesh deformation method for handling wing-fuselage intersections

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Chinese Journal of Aeronautics 2017年第1期30卷 264-273页

作者： Mario Jaime Martin-Burgos Daniel González-Juárez Esther andrés-Pérez Fluid Dynamics Branch National Institute for Aerospace Technology (INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Engineering Department lngenieria de Sistemas para la Defensa de Espana (ISDEFE-INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Technical University of Madrid (UPM) Ronda de Valencia 3 28012 Madrid Spain

This paper describes a method for mesh adaptation in the presence of intersections, such as wing-fuselage. Automatic optimization tools, using Computational Fluid Dynamics（CFD） simulations, face the problem to adapt the computational grid upon deformations of the boundary surface. When mesh regeneration is not feasible, due to the high cost to build up the computational grid, mesh deformation techniques are considered a cheap approach to adapt the mesh to changes on the geometry. Mesh adaptation is a well-known subject in the literature; however, there is very little work which deals with moving intersections. Without a proper treatment of the intersections,the use of automatic optimization methods for aircraft design is limited to individual *** proposed method takes advantage of the CAD description, which usually comes in the form of Non-Uniform Rational B-Splines（NURBS） patches. This paper describes an algorithm to recalculate the intersection line between two parametric surfaces. Then, the surface mesh is adapted to the moving intersection in parametric coordinates. Finally, the deformation is propagated through the volumetric mesh. The proposed method is tested with the DLR F6 wing-body configuration.

关键词： Aerodynamic shape optimization Computational fluid dynamics Computer-assisted design Geometry parameterizationMesh deformation Non-Uniform Rational B-Splines

Genetic differentiation of grain, fodder and pod vegetable type cowpeas (Vigna unguiculata L.) identified through single nucleotide polymorphisms from genotyping-by-sequencing

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Molecular Horticulture 2022年第1期2卷 101-115页

作者： Xingbo Wu andrés JCortés Matthew W.Blair Department of Agricultural and Environmental Sciences Tennessee State UniversityNashvilleTN 37209USA Tropical Research and Education Center Department of Environmental HorticulturalUniversity of Florida18905 SW 280th StHomesteadFL 33031USA Corporación Colombiana de Investigación Agropecuaria AGROSAVIA C.I.La SelvaKm 7 vía Rionegro–Las PalmasRionegroColombia Universidad Nacional de Colombia–Sede Medellín Facultad de Ciencias Agrarias–Departamento de Ciencias ForestalesMedellínColombia

The species Vigna unguiculata L.(Walp),commonly known as cowpea,is a multi-purpose legume that has been selected into three subspecies that are divided into grain,fodder and pod(yardlong bean)***,genetic bases for distinctions are not well *** purpose of this study was to apply genotyping-by-sequencing(GBS)and current reference genome for *** to distinguish three subspecies and identify signatures of *** collection of 130 accessions included 128 cultivated from:1)***,fodder type;2)***,pod vegetable type;and 3)***,grain *** wilds genotypes from *** and ***,were used to anchor phylogeny.A total of 11,083 highly informative single nucleotide polymorphisms(SNPs)were *** accessions showed distinct genetic fingerprints and were separated from cultivated *** component analysis showed closer relationship between *** and *** compared to *** differentiation of cultivated subspecies(with Fixation Index,FST)indicated the existence of discrete signatures of *** work clarifies the population structure,phylogeny,and domestication of cultivated ***,significant genetic differences between grain and pod vegetable types can provide valuable information for future breeding in three cowpea groups.

关键词： Genomic landscape of divergence Relative differentiation FST GBS-derived SNP markers

Ruthenium promotion of Co/SBA-15 catalysts for Fischer-Tropsch synthesis in slurry-phase reactors

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Journal of Natural Gas Chemistry 2012年第6期21卷 722-728页

作者： Jocielys Jovelino Rodrigues Gina Pecchi Fabiano andrNarciso Fernandes Meiry Glucia Freire Rodrigues Federal University of Campina Grande Academic Unit of Chemical Engineering Facultad de Ciencias Químicas Departamento de Físico-QuímicaUniversidad de Concepción Federal University of Ceara Department of Chemical Engineering

The aim of this work was to evaluate the catalytic properties of a Ru promoted Co/SBA-15 catalyst for Fischer-Tropsch synthesis （FTS）. The Ru promoted Co/SBA-15 catalyst was prepared by wet impregnation method and was characterized by X-ray diffraction, X-ray energy dispersion spectrophotometer, N2 adsorption-desorption, temperature-programmed reduction and transmission electron microscopy. The Fischer-Tropsch synthesis using the catalyst was carried out to evaluate the catalyst activity and its effect on FTS product distribution. The synthesis was carried out in a slurry reactor operating at 513 K, 20 atm, CO ： H2 molar ratio of 1 ： 1. X-ray diffraction showed that the calcined cobalt catalyst did not modify the structure of SBA-15, proving that Co was present in the form of Co3O4 in the catalyst. The addition of cobalt in SBA-15 decreased the specific superficial area of the molecular sieve. Fischer-Tropsch synthesis activity and C5＋ hydrocarbon selectivity increased with the addition of Ru. The increases in activity and selectivity were attributed to the increased number of active sites resulting from higher reducibility and the synergetic effect of Ru and Co. Ru/Co/SBA-15 catalysts showed moderate conversion （40%） and high selectivity towards the production of C5＋（80 wt%）.

关键词： SBA-15 cobalt ruthenium heterogeneous catalyst slurry reactor Fischer-Tropsch synthesis

Punctual mutations in 23S rRNA gene of clarithromycinresistant Helicobacter pylori in Colombian populations

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World Journal of Gastroenterology 2018年第14期24卷 1531-1539页

作者： andrés Jenuer Matta Diana Carolina Zambrano Alvaro Jairo Pazos Registro Poblacional de Cáncer de Cali Department of Pathology School of Medicine Universidad del Valle Faculty of Education and Sports Sciences Institución Universitaria Escuela Nacional del Deporte Department of Biology Universidad de Nari?o

AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic *** PCR products of 23S rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC) population: TumacoColombia, and 5 from a high-risk population: TuquerresColombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23S rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin ***23S rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, C1770 T, C1954 T1, and G1827 C in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 C, A2144 G and C2196 T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H. pylori(κ = 0.71).CONCLUSION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H. pylori.

关键词： Clarithromycin In vitro resistance Point mutation Helicobacter pylori Gastric cancer 23S rRNA