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Acta Geologica Sinica(English Edition) 2005年第1期79卷 36-42页

作者： XUShunshan A.F.nieto-SAMANIEGO S.A.ALANIZ-ALVAREZ InstitutoMexicanodelPetrǒleo ProgramaYNFEjeCentralLázaroCárdenasNo.152Col.SanBartoloAtepehuacánC.P.07730 UniversidadNacionalAutǒnomadeMěxico CentrodegeocienciaApartadoPostal1-74276001QuerětaroQro.Měxoco／／InstituteofGeomechnicsChineseAcademyofGeologicalSciencesBeijing100081China.

The Sierra de San Miguelito is a relatively uplifted area and is constituted by a large amount of silicic volcanic rocks with ages from middle to late Cenozoic. The normal faults of the Sierra de San Miguelito are Domino-style and nearly parallel. The cumulative length and displacement of the faults obey power-law distribution. The fractal dimension of the fault traces is -1.49. Using the multi-line one-dimensional sampling, the calculated exponent of cumulative fault displacements is -0.66. A cumulative curve combining measurements of all four sections yielded a slope of -0.63. The displacement-length plot shows a non-linear relationship and large dispersion of data. The large dispersion in the plot is mainly due to the fault linkage during faulting. An estimation of extensional strain due to the normal faults is ca. 0.1830. The bed extension strain is always less than or equal to the horizontal extension strain. The deformation in the Sierra de San Miguelito occurred near the surface, producing pervasive faults and many faults are too small to appear in maps and sections at common scales. The stretching produced by small faults reach ca. 33% of the total horizontal elongation.

关键词： power-law distribution normal faults small faults finite strain Mexico

NiO-CaO materials as promising catalysts for hydrogen production through carbon dioxide capture and subsequent dry methane reforming

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Journal of Energy Chemistry 2017年第5期26卷 942-947页

作者： Alejandra Cruz-Hernández J.Arturo Mendoza-nieto Heriberto Pfeiffer Laboratorio de Fisicoquímica y Reactividad de Superficies(LaFReS) Instituto de Investigaciones en MaterialesUniversidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510Ciudad de MéxicoMexico

In this work, CaO-NiO mixed oxide powders were evaluated as consecutive CO;chemisorbents and catalytic materials for hydrogen production thought the CH;reforming process. Between the NiO impregnated CaO and CaO-NiO mechanical composite, the first one presented better chemical behaviors during the CO;capture and CH;reforming processes, obtaining syngas（H;+ CO） as final product. Results showed that syngas was produced at two different temperature ranges, between 400 and 600 °C and at T > 800 °C, where the first temperature range corresponds to the CH;reforming process but the second temperature range was attributed to a different catalytic reaction process: CH;partial oxidation. These results were confirmed through different isothermal and cyclic experiments as well as by XRD analysis of the final catalytic products, where the nickel reduction was evidenced. Moreover, when a CO-O;flow was used during the carbonation process a triple process was achieved:（i） CO oxidation,（ii） CO;chemisorption and（iii） CH;reforming. Using this gas flow the hydrogen production was always higher than that obtained with CO;.

关键词： Methane reforming CO2 capture Calcium oxide H2 production NiO supported

Dominance by an obligate annual affects the morphological characteristics and biomass production of a planted wetland macrophyte community

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Journal of Plant Ecology 2016年第2期9卷 187-200页

作者： alicia R.Korol Changwoo Ahn Department of Environmental Science and Policy 4400 University DriveMS5F2George Mason UniversityFairfaxVA 22030USA

Aims Biodiversity-ecosystem function experiments can test for causal relationships between planting diversity and community *** diversity is routinely introduced as a design element in created wetlands,yet substantive support for the finding that early diversity positively affects ecosystem functioning is lacking for *** conducted a 2-year diversity-productivity experiment using freshwater wetland mesocosms to investigate community biomass production as affected by planted macrophyte functional *** A richness gradient of macrophytes in four emergent wetland plant functional groups was established in freshwater mesocosms for two consecutive ***-specific aboveground morphological traits of plant size were measured at peak growth in both years;rooting depth was measured for each species in the second *** biomass(AGB)and belowground biomass(BGB)were harvested after peak growth in the second year;first year AGB was estimated from morphological traits in constructed regression *** richness effects(*** complementarity effects and selection effects)were calculated using an additive partitioning *** Findings Species richness had a positive effect on community AGB relative to monocultures in the first *** the second year,mean AGB was significantly reduced by competition in the most species-rich mixtures and all mixtures underyielded relative to the average *** for soil resources was weaker belowground,whereby root distribution at depths>20cm was reduced at the highest richness levels but overall BGB production was not *** in species biomass were strongly reflected by variation in species morphological traits,and species above and belowground performances were highly *** obligate annual(Eleocharis obtusa),a dominant competitor,significantly contributed to the depression of perennial species’growth in the second growing *** foster prima

关键词： complementarity effect created wetland macrophyte richness morphological trait plant biomass diversity–productivity relationship

Long-term economic sensitivity analysis of light duty underground mining vehicles by power source

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International Journal of Mining Science and Technology 2017年第3期27卷 567-571页

作者： Schatz Richard S. nieto Antonio Lvov Serguei N. The EMS Energy Institute College of Earth and Mineral Engineering The Pennsylvania State University State College PA 16802 USA Department of Energy and Mineral Engineering College of Earth and Mineral Engineering The Pennsylvania State University State College PA 16802 USA Department of Materials Science and Engineering College of Earth and Mineral Engineering The Pennsylvania State University State College PA 16802 USA

LHD's are expensive vehicles; therefore, it is important to accurately define the financial consequences associated with the investment of purchasing the mining equipment. This study concentrates on longterm incremental and sensitivity analysis to determine whether it is feasible to incorporate current battery technology into these machines. When revenue was taken into account, decreasing the amount of haulage in battery operated equipment by 5% or 200 kg per h amounts to a $4.0 × 10~4 loss of profit per year. On average it was found that using battery operated equipment generated $9.5 × 10~4 more in income annually, reducing the payback period from seven to two years to pay back the additional $1.0 × 10~5 investment of buying battery powered equipment over cheaper diesel equipment. Due to the estimated 5% increase in capital, it was observed that electric vehicles must possess a lifetime that is a minimum of one year longer than that of diesel equipment.

关键词： Sensitivity analysis Underground mining vehicles Battery power Battery mining equipment Economic evaluation

3D Modal Solution for Tidally Induced Lagrangian Residual Velocity with Variations in Eddy Viscosity and Bathymetry in a Narrow Model Bay

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Journal of Ocean University of China 2019年第1期18卷 69-79页

作者： DENG Fangjing JIANG Wensheng valle-LEVINSON Arnoldo FENG Shizuo Physical Oceanography Laboratory/CIMST Ocean University of China and Qingdao National Laboratory for Marine Science and Technology Laboratory of Marine Environment and Ecology Ocean University of China Department of Civil and Coastal Engineering University of Florida

In this study, we examine the results obtained by the Finite-volume Coastal Ocean Circulation Model(FVCOM) regarding the effects of eddy viscosity and bathymetry on the three-dimensional(3 D) Lagrangian residual velocity(LRV) in a narrow bay. The results are cast in terms of two nondimensional numbers: the ratio of friction to local acceleration(δ) and the ratio of the minimum depth over shoals to the maximum depth in the channel(ε). The ratio δ depends on the eddy viscosity and mean depth. For a given eddy viscosity, when ε > 0.5, the along-estuary LRV tends to be vertically sheared and when ε < 0.5, the exchange is laterally sheared. When ε << 1, the structure of the 3 D, depth-integrated, and breadth-averaged LRV changes only slightly as δ increases. For ε values between 0.33 and 0.5, the structure of the 3 D LRV is mainly laterally sheared. In the same ε range, the 3 D and depth-integrated LRV exhibit reversed structures from high to low δ values. In addition, the breadth-averaged LRV weakens the typical twolayered circulation when δ decreases. When ε is 1, the two-layered vertical structure reverses direction, and a three-layered vertical structure develops in the outer bay as δ decreases.

关键词： eddy viscosity bathymetric effects Lagrangian residual velocity 3D narrow bay

Biomaterials for Adhesion in Orthopedic Applications:A Review

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再生工程(英文) 2020年第1期1卷 51-63页

作者： Younis Zaokari alicia Persaud Amr Ibrahim Biomedical Engineering Department College of Engineering and Applied SciencesStony Brook UniversityUnited States

Adhesive biomaterials,historically,have had a wide range of applications in all medical *** the extensive variety of biomaterials with adhesion properties,the field of orthopedics benefits from using adhesives which can provide superior biocompatibility,resorbability,and low *** goal of this review is to serve as a reference of the types of adhesive biomaterials used clinically and their specific applicability in the field of *** applications of adhesive biomaterials in orthopedics are as scaffolds,filler materials to treat bone defects and as carrier materials to deposit other bioactive materials to a ***,we review the history and background of adhesive biomaterials and some of their general applications in *** we focus on the various types of adhesive biomaterials which include fibrin,collagen,polyurethane,epoxy resin,cyanoacrylates,polyesters and polymethylmethacrylate,all of which are excellent candidates for the field of *** discuss their properties,current applications in all fields,and advantages and disadvantages found in some ***,we indicate some future directions for adhesive biomaterials in orthopedics and highlight their advantages over conventional biomaterials in orthopedics.

关键词： Adhesive biomaterials Orthopedic biomaterials Osteoinduction Polymer-based biomaterials Fibrin biomaterials

2-Cys Peroxiredoxins Participate in the Oxidation of Chloroplast Enzymes in the Dark

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Molecular Plant 2018年第11期11卷 1377-1388页

作者： valle Ojeda Juan Manuel Perez-Ruiz Francisco Javier Cejudo Instituto de Bioquimica Vegetaly Fotosintesis Universidad de Sevilla and Consejo Superior de lnvestigaciones CientificasAvenida Americo Vespucio 4941092SevillaSpain

Most redox-regulated chloroplast enzymes are reduced during the day and oxidized during the *** the reduction mechanism of light-dependent enzymes is well known,the mechanism mediating their oxidation in the dark remains *** thiol-dependent peroxidases,2-Cys peroxiredoxins (Prxs),play a key role in light-dependent reduction of chloroplast *** transfer reducing equivalents of thiols to hydrogen peroxide,suggesting the participation of these peroxidases in enzyme oxidation in the ***,we have addressed this issue by analyzing the redox state of well-known redox-regulated chloroplast enzymes in response to darkness in Arabidopsis thaliana mutants deficient in chloroplastlocalized Prxs (2-Cys Prxs A and B,Prx ⅡE,and Prx Q).Mutant plants lacking 2-Cys Prxs A and B,and plants overexpressing NADPH-dependent thioredoxin (Trx) reductase C showed delayed oxidation of chloroplast enzymes in the *** contrast,the deficiencies of Prx ⅡE or Prx Q exerted no *** vitro assays allowed the reconstitution of the pathway of reducing equivalents from reduced fructose 1,6-bisphosphatase to hydrogen peroxide mediated by Trxs and 2-Cys *** together,these results suggest that 2-Cys Prxs participate in the short-term oxidation of chloroplast enzymes in the dark.

关键词： chloroplast enzyme oxidation peroxiredoxin thioredoxin hydrogen peroxide darkness

The number of alignments between two DNA sequences

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International Journal of Biomathematics 2016年第4期9卷 75-80页

作者： Helena Andrade Juan J. nieto Angela Torres Departamento de Andlisis Matemdtico Facultad de Matemdticas Universidad de Santiago de Compostela Spain Department of Mathematics Faculty of ScienceKing Abdulaziz University Jeddah 21589 Saudi Arabia Departamento de Psiquiatrla Radiologla y Salud Publica Facultad de Medicina Universidad de Santiago de Compostela Spain

We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between both sequences. The number of alignments grows very rapidly with the length of the sequences. In this paper we give exact, explicit and computable formulas for the number of different possible alignments and for some classes of reduced alignments. We provide a new insight into the theory of DNA sequence alignment.

关键词： DNA sequence alignment difference equation.

Glial kon/NG2 gene network for central nervous system repair

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Neural Regeneration Research 2017年第1期12卷 31-34页

作者： Maria Losada-Perez Neale Harrison alicia Hidalgo School of Biosciences University of BirminghamBirminghamEnglandUK Universidad Autonoma de Madrid MadridSpain

The glial regenerative response to central nervous system（CNS） injury,although limited,can be harnessed to promote regeneration and *** provokes the proliferation of ensheathing glial cells,which can differentiate to remyelinate axons,and partially restore *** response is evolutionarily conserved,strongly implying an underlying genetic *** mammals,it is elicited by NG2 glia,but most often newly generated cells fail to *** an important goal had been to find out how to promote glial differentiation following the proliferative response.A gene network involving Notch and prospero（pros） controls the balance between glial proliferation and differentiation in flies and mice,and promotes CNS repair at least in fruit-flies.A key missing link had been how to relate the function of NG2 to this gene *** findings by Losada-Perez et al.,published in JCB,demonstrated that the Drosophila NG2 homologue kon-tiki（kon） is functionally linked to Notch and pros in *** engaging in two feedback loops with Notch and Pros,in response to injury,Kon can regulate both glial cell number and glial shape homeostasis,essential for *** offers powerful genetics to unravel the control of stem and progenitor cells for regeneration and repair.

关键词： NG2 kon-tiki glia Drosophila injury regeneration repair CNS

Impulsive perturbation and bifurcation of solutions for a model of chemostat with variable yield

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Applied Mathematics and Mechanics(English Edition) 2009年第7期30卷 933-944页

作者：张弘 Paul Georgescu Juan J.nieto 陈兰荪 Department of Mathematics Jiangsu University Department of Mathematics and Mathematical Statistics Ume University Department of Mathematics "Gh.Asachi" Technical University of Iasi Departamento de Análisis Matemático Facultad de Matemáticas Universidadde Santiago de Compostela Institute of Mathematics Chinese Academy of Sciences

In this paper, we consider a variable yield model of a single-species growth in a well-stirred tank containing fresh medium, assuming the instances of time as triggering factors in which the nutrient refilling process and the removal of microorganisms by the uptake of lethal external antibiotic are initiated. It is also assumed that the periodic nutrient refilling and the periodic antibiotic injection occur with the same periodicity, but not simultaneously. The model is then formulated in terms of autonomous differential equations subject to impulsive perturbations. It is observed that either the population of microorganisms essentially washes out, or more favorably, the system is permanent. To describe this dichotomy, some biologically significant integral conditions are introduced. Further, it is shown that in a certain critical situation, a nontriviai periodic solution emerges via a bifurcation phenomenon. Finally, the dynamics of the model is illustrated with numerical experiments and computer simulations.

关键词： chemostat impulsive differential equation permanence extinction fixedpoint approach bifurcation