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Spectral Comparison of Real Spectra with Site Effects Included vs MOC-2008 Teorical Spectra for Guadalajara City, Mexico

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Open Journal of Civil Engineering 2013年第3期3卷 194-201页

作者： h.ctor E. Rodríguez Lozoya Tonatiuh Domínguez Reyes Alfredo Reyes Salazar Edén Bojórquez Mora h.ctor E. Rodríguez Leyva Facultad de Ingeniería Universidad Autónoma de Sinaloa México D.F. México Observatorio Vulcanológico Universidad de Colima México D.F. México

Guadalajara city is the capital of the Mexican federal state of Jalisco. It is located close to the Pacific coast and is subjected to a large seismic risk. We present a seismic response study for some sites along the city. We calculated response spectra of shear-waves by using seismic records of actual earthquakes registered on rock and near the source as Green functions and propagated them trough a flat and horizontal layered media using a linear equivalent method to compare them with the response spectra calculated according to the Federal Commission of Electricity (CFE) seismic design buildings Manual (MOC-2008, 2008) which is widely used as reference on construction projects in Mexico. Our results show that MOC-2008 manual underestimates the spectral amplitudes and frequency band for the response spectra.

关键词： Response Spectra Guadalajara Seismic Records Green Function

Identification of Bulge Stem Cells in Mouse and human hair Follicles

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Microscopy Research 2018年第3期6卷 19-29页

作者： Bélgica J. Molina Elda Giansante h.ctor J. Finol Center of Electron Microscopy Science Faculty Central University of Venezuela Caracas Venezuela Dermatology Service University hospital of Caracas Caracas Venezuela

The skin contains various populaions of stem cells, but its characterization has been hampered by lack of markers and unclear location. The hair follicle has a niche for stem cells called a “bulge” which acts as a reservoir of multipotent stem cells. In the study reported here, an immunohistochemical and immunofluorescence analysis was performed on mouse and human tissues in order to determine the possible presence of stem cells of hair follicle through cytokeratin 15 (CK15), CD34, and CD200 markers identified as crucial to the stem cells and to identify the bulge region. Mouse (n = 7) and human (n = 7) skin samples were used. The expression of proteins was determined by the indirect immunoperoxidase technique and a secondary antibody bound to a fluorochrome. The specificity of staining was evaluated by negative controls. The results revealed that the stem cells associated with CD34 and CD200 antibodies were differentially expressed in the interfollicular epidermis, sebaceous glands, and bulge region, indicating that, in mice, CD34 and, in humans, CD200 are more specific than CK15 in detecting bulge cells. It also suggests that CD34 is specific for mouse bulge cells, while CD200 might have specificity for progenitor cells and partially differentiated cells in humans.

关键词： Stem Cells hair Follicle Bulge CD34 CD200

An Application of Bessel Functions： Study of Transient Flow in a Cylindrical Pipe

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Journal of Mathematics and System Science 2016年第2期6卷 72-79页

作者： A. E. García Luz María García Cruz h.ctor Luna-García Area de Fisica Atómica Molecular Aplicada CBL UAM-A Avenida San Pablo 180 Colonia Reynosa Azcapotzalco México D.F. 02200 México

The Navier-Stokes equations for a fluid flow are applied to a pipe. Under conditions of symmetry these are reduced to the well-known equation ofzeroth modified Bessel, which is solved to find the velocity profile and ... 详细信息

关键词：贝塞尔函数 Navier-Stokes 瞬变流动管道圆柱形斯托克斯方程应用流体流动

Calculation of Infinite Series Through Polygamma Functions＇ Algorithms and Laplace Transforms

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Journal of Mathematics and System Science 2013年第2期3卷 110-113页

作者： h.ctor Luna-Garcia Luz Maria Garcia Cruz R. Mares Area de Fisica Atómica Molecular Aplicada CBI UAM-A Azcapotzalco México 02200 México Departamento de Fisica ESFM IPN Edificio 9. U.P. Zacatenco México 07738 México

here is introduced some novel algorithms which made use of polygarnma functions to get the exact limits of a broad class of infinite series. Moreover, Laplace transform is used to find the sum of many convergent infinite series. These exact limits are found in different branches of physics for some special cases series and are in complete agreement with the values found by other authors. Moreover, the methods presented here are generalized and applied to other wide variety of sums, including alternating series. Finally, these methods are simple and quite powerful to calculate the limits of many convergent series as you can see from the examples included.

关键词： Polygamma function Laplace transform infinite series.

Groundwater Origin and Its hydrogeochemistry through GIS Maps in Linares Region, Mexico

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Journal of Water Resource and Protection 2013年第8期5卷 1-12页

作者： René Alberto Dávila Pórcel h.ctor de León-Gómez Instituto de Ingeniería Civil (IIC) Facultad de Ingeniería Civil (FIC) Universidad Autónoma de Nuevo León (UANL) Monterrey México

The North-East region of Mexican Republic has a semi-arid weather condition;this area covers partially Tamaulipas, Nuevo León and Coahuila states. Pablillo River Basin (PRB) is located close to Nuevo León south border and its catchment area involves Linares City (LC), hualahuises City (hC) and Cerro-Prieto dam (CP). This reservoir captures drinking water to Monterrey Metropolitan Zone (MMZ) the major urban center on the north-east Mexican region. More than 50% of the potable water for LC comes from groundwater stockpiles. A combination of GIS maps and major ion chemistry analysis has been assessed, to know the origin, geochemical evolution, and hydraulic interconnection of groundwater. During 2008-2009, 46 groundwater samples were taken and analyzed around LC and hC. GIS technology was use to analyze the spatial distribution of the constituents of groundwater through thematic maps. The major ion analysis and its results suggest the presences of two aquifers;shallow porous aquifer on the top and fractured aquifer on the bottom. General water mineralization was discovered, including dissolution of halite, dolomites and carbonates through the aquifers. Water quality varies widely through the aquifers, and the general pathways go from southwest to northeast direction. The overexploitation of groundwater increases the water mixing of groundwater between shallow and deeper aquifers. Natural origin of groundwater and groundwater pollution by anthropogenic activities should be considered in the groundwater quality analysis for drinking water purpose.

关键词： Groundwater hydrogeochemistry GIS Mexico

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墨西哥红豆杉愈伤组织的诱导和器官发生

植物生理学通讯 2000年第6期36卷 536-537页

作者：肖尊安 h.ctor Barrios Consuelo Sandoval Garc姫a 北京师范大学生命科学学院北京100875 墨西哥国立自治大学化学研究所墨西哥城04510

植物名称墨西哥红豆杉(Taxus globo-sa)。2 材料类别墨西哥州 Pachuca县hidalgo山森林中自然生长的墨西哥红豆杉成年树当年生成熟枝(9月份取样)。3 培养条件愈伤组织诱导培养基是Sh，B5和NN69基本培养基添加NAA 2.0 mg·L-1、BA 0.1 mg... 详细信息

植物名称墨西哥红豆杉(Taxus globo-sa)。2 材料类别墨西哥州 Pachuca县hidalgo山森林中自然生长的墨西哥红豆杉成年树当年生成熟枝(9月份取样)。3 培养条件愈伤组织诱导培养基是Sh，B5和NN69基本培养基添加NAA 2.0 mg·L-1、BA 0.1 mg·L-1、3％蔗糖和0.6％琼脂(ph 5.6)。此外，变换Sh愈伤组织诱导培养基中的BA浓度为0.03、0.2、0.5和1.0mg·L-1。愈伤组织每6周继代1次。继代培养基是Sh基本培养基，添加NAA 2.0mg·L-1和BA 0.05 mg·L-1，其它成分同上。培养温度为20～25℃，暗中培养。4 生长与分化情况4.1 不同培养基对愈伤组织诱导和生长的影响墨西哥红豆杉茎段接种后2～4周，诱导出白色疏松的愈伤组织；随着愈伤组织逐渐生长，愈伤组织颜色转变为棕色或褐色。接种后6周，NN69培养基的出愈率最高，达67.5％；其次为B5培养基(32.6％)和Sh培养基(31.6％)。愈伤组织继续生长2～4周后，所有茎段愈伤组织生长缓慢直至停止，愈伤组织颜色变为棕褐或黑褐色。经过4～8周的停滞生长后，大部分茎段愈伤组织重新恢复生长。此后，愈伤组织每6周继代1次。在继代培养中，Sh培养基上的愈伤组织生长最快，其次为B5和NN69培养基。4.2 BA浓度对愈伤组织诱导的影响在Sh培养基上添加不同浓度BA影响茎段愈伤组织的诱导。BA 0.1 mg·L-1的愈伤组织诱导率最高，达37.1％；BA浓度低于或高于0.1时，愈伤组织诱导率都降低，如0.03、0.2、0.5和1.0 BA的愈伤组织诱导率分别是25.0％、13.6％、16.7％和26.9％。BA浓度在0.2～1.0范围内，随着浓度升高，愈伤组织诱导率出现逐渐增加的趋势。4.3 不定根的分化和生长当愈伤组织在Sh继代培养基上继代培养3次后，有5个愈伤组织系分化出白色幼嫩的不定根，其生长状态不一样。愈伤组织系10-2生长最快，平均每周每g愈伤组织增加0.40 g，仅有1块愈伤组织分化1条生长细弱的不定根。虽然愈伤组织系10-1和10-3平均每周每g愈伤组织增加0.24 g和0.25 g，各有1块愈伤组织分化不定根，但是每块愈伤组织分化3～5条生长旺盛的不定根。愈伤组织系10-4、10-5和12-1的生长与10-1和10-3相似，平均每周每g愈伤组织分别增加0.19、0.23和0.27 g，不同的是前者有较多的愈伤组织分化不定根(分别为5、4和7块愈伤组织)，并且每块愈伤组织仅分化1条不定根。说明墨西哥红豆杉茎段愈伤组织系的生长量越大，其不定根分化的能力越小；愈伤组织系具有较多愈伤组织分化不定根，每块愈伤组织分化的不定根数量少和生长较弱；只有愈伤组织系生长量适中且较少愈伤组织分化的不定根生长旺盛。愈伤组织发生不定根的能力在以后2～3次继代过程中消失，没有愈伤组织系继续再生不定根。我们用不同培养方法诱导墨西哥红豆杉愈伤组织分化不定芽，至今尚未成功。5 意义与进展墨西哥红豆杉为红豆杉科红豆杉属植物，其紫杉醇含量较高。研究墨西哥红豆杉愈伤组织的诱导对于进一步进行细胞悬浮培养和离体生产紫杉醇会有所帮助。此外，墨西哥红豆杉愈伤组织直接在继代培养过程中分化不定根，表明红豆杉当年生成熟枝条茎段愈伤组织具有一定的再生能力。本文结果对研究诱导红豆杉茎段愈伤组织不定芽的再生可能有一定的参考意义。迄今尚未见到墨西哥红豆杉组织培养的报道。

关键词：墨西哥红豆杉愈伤组织诱导器官发生

Diversity of Saxicolous Lichens along an Aridity Gradient in Central México

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Phyton-International Journal of Experimental Botany 2022年第4期91卷 827-840页

作者： JoséCarmen Soto-Correa Abraham Saldaña-Vega Víctor hugo Cambrón-Sandoval Laura Concostrina-Zubiri Mariela Gómez-Romero Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroQuerétaro73230México Departamento de Biología y Geología Física y Química Inorgánica Tulipán s/nUniversidad Rey Juan CarlosMóstolesMadrid28933España Cátedra CONACYT–Facultad de Biología Universidad Michoacana de San Nicolás de HidalgoMoreliaMichoacán58030México

Lichens are symbiotic organisms that comprise a fungus and a photosynthetic partner wich are recognized as a good indicator of climate ***,our understanding of how aridity affects the diversity of saxicolous lichens in drylands is still *** evaluate the relationship between saxicolous lichen diversity and aridity in a central México dryland,a geographical transect was established of 100 km to build an aridity gradient in the semiarid zone of the State of Querétaro,Mexico,comprising ten sampling sites with a 10 km *** richness,abundance and diversity of soil lichen species were recorded using two sampling methods:the quadrat-intercept and the line-intercept method,to compare their performance in assessing soil lichen diversity in *** number of species and Shannon diversity of saxicolous lichens were higher at intermediate values of the aridity index(AI=0.10-0.34).Quadrat intercept and point intercept methods gave quite similar results,which means that the selected method does not influence the results in a significant *** study confirms the role of saxicolous lichens as climate change indicators and reveals the importance of the sampling method selection in the evaluation of different parameters of soil lichen diversity in drylands.

关键词： Climate change drylands ecological indicators environmental stress precipitation temperature

Effects of Plant Extracts and Beauveria bassiana on the Activity of Defense-Related Enzymes in Solanum lycopersicum *** Interaction with Fusarium oxysporum ***

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Phyton-International Journal of Experimental Botany 2023年第9期92卷 2503-2518页

作者： JoséAdrian Perez-Robles Carlos Alberto Lecona-Guzmán Víctor Manuel Ruíz-Valdiviezo Joaquín Adolfo Montes-Molina Laboratorio de Biotecnología Vegetal Tecnológico Nacional de MexicoCampus Tuxtla GutiérrezTuxtla Gutiérrez29050Mexico

The objective to this work was to evaluate the enzymatic activity in the culture of Solanum lycopersicum *** with Fusarium oxysporum after the combined application of Beauveria bassiana and plant *** lycopersicum plantlets were transplanted 15 days after the *** days after transplanting,Beauveria bassiana spores were applied at a concentration of 1×10^(7)spores mL^(−1)onto soil(along with ***(N)and ***(h)leaf extracts)where *** plants were *** days after transplanting,spores of *** strain were applied at a concentration of 1×10^(6)spores mL^(−1)to soil where *** plants were *** development of *** plants was monitored for 114 days,whereby a randomized complete block treatment design was used,the roots of the plants were crushed with liquid nitrogen,after which UV/VIS spectrophotometry was used to determine protein concentration,as well as the activity ofβ-1,3-glucanases,peroxidases(POX,EC1.***.1.7),catalase and *** treatments combining *** and *** and *** extracts,had a significant difference in enzymatic activity levels,thus contributing to better defense mechanisms and a greater protection to *** plants in the presence of *** application of *** and plant extracts to the ground mitigated damage caused by *** on *** plants.

关键词： Glucanases chitinases peroxidases catalase defense mechanisms

Kinetic Rates of the Fischer Tropsch Synthesis on a Co/Nb_2O_5 Catalyst

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Journal of Natural Gas Chemistry 2006年第4期15卷 307-312页

作者： Víctor R.Ahón Paulo L.C.Lage Carlos D.D.de Souza Fabiana M.Mendes Martin Schmal Federal University of Rio de Janeiro Programa de Engenharia Química COPPE/UFRJ C.P.6850221941-972Rio de JaneiroRJBrazil

The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions （T=543 K, P=2.1 MPa） and under different conditions of several h2/CO feed molar ratio （0.49-4.79）, space velocities （0.2-3.8 h^-1）, mass of catalyst （0.3-1.5 g）, and CO conversion （10%-29%）. Synthesis gas conversion was measured and data were reduced to estimate the kinetic parameters for different Langmuir-hinshelwood rate expressions. Differential and integral reactor models were used for the nonlinear regression of kinetics parameters. One of the rate equations could well explain the data. The hydrocarbon product distributions that were experimentally determined exhibited an unusual behavior, and a possible explanation was discussed.

关键词： Fischer-Tropsch natural gas kinetics selectivity