• Title/Summary/Keyword: Mexico

Search Result 629, Processing Time 0.029 seconds

A Study on the Growth and Exchange of Cotton during the Classic Mesoamerica

  • Ahn, Cheun-Soon
    • The International Journal of Costume Culture
    • /
    • v.12 no.2
    • /
    • pp.153-162
    • /
    • 2009
  • This paper introduces the probable regional and long distance trade of cotton goods among the pre-Hispanic Mesoamericans during the Classic (A.D. 200-900) period through the comparison of the available documentary sources. Based on the ethnohistoric data and the archaeological evidences it was found that cotton was used throughout the Mesoamerica by the elite ruling class. However, because cotton could not be grown at elevations above 6,000 feet it was obvious that nations such as Teotihuacan which flourished in the highland of present day Mexico City had to import cotton from the tropical coastal hotlands either through trade or tribute. Several ethnohistorical and archaeological data suggest that urban center in highland Mexico had people employed in weaving the textiles rather than cultivating or spinning cotton. Archaeological evidences such as the workshops used by the craft specialists seemed to be associated with weaving of cotton. Because of the similarity in climatic conditions for marine shells and cotton cultivation, Kolb's model seems to be applicable to the cotton trade of the classic Teotihuacan. Based on Kolb's model, it could be hypothesized that Teotihuacan-Kaminaljyyu-Maya was the indirect trade route connecting the Basin of Mexico and the Mayan regions.

  • PDF

New Record of Sargassum filicinum Harvey (Fucales, Phaeophyceae) in the Pacific Coast of Mexico

  • Aguilar-Rosas, Luis E.;Aguilar-Rosas, Raul;Kawai, Hiroshi;Uwai, Shinya;Valenzuela-Espinoza, Enrique
    • ALGAE
    • /
    • v.22 no.1
    • /
    • pp.17-21
    • /
    • 2007
  • Sargassum filicinum Harvey, a brown alga (Phaeophyceae) native to Northeastern Asia, has been recently reported from the coast of Southern California (USA). Here we report the occurrence and range extension of this introduced species, as we found the alga at La Jolla and Rancho Packard in Todos Santos Bay, Baja California, Mexico. The first collections of S. filicinum correspond to several immature plants, found on September 8, 2005, drifting in the intertidal zone at La Jolla. Later on November 9, 2006, we found a well-established population in Rancho Packard in the middle intertidal zone to 2 m depth. Since S. filicinum is an annual monoecious species with air bladders, the risk there is a high risk of spreading rapidly along the Pacific, as in the case for S. muticum. The population in Rancho Packard extends 500 m along the coast, consisting mainly of young plants with an average length of 30 cm and a density of 5 thallus/m2. This is the first record of this invasive species for the Mexican Pacific coast, and it represents the southern limit along the Pacific coast of North America. This finding suggests that this invasive species has successfully colonized the Pacific coast of North America and its distributional range is still expanding.

REMOTE NUMERICAL SIMULATIONS OF THE INTERACTION OF HIGH VELOCITY CLOUDS WITH RANDOM MAGNETIC FIELDS

  • Santikkan, Alfredo;Hernandez-Cervantes, Liliana;Gonzalez-Ponce, Alejandro;Kim, Jong-Soo
    • Journal of The Korean Astronomical Society
    • /
    • v.40 no.4
    • /
    • pp.165-169
    • /
    • 2007
  • The numerical simulations associated with the interaction of High Velocity Clouds (HVC) with the Magnetized Galactic Interstellar Medium (ISM) are a powerful tool to describe the evolution of the interaction of these objects in our Galaxy. In this work we present a new project referred to as Theoretical Virtual i Observatories. It is oriented toward to perform numerical simulations in real time through a Web page. This is a powerful astrophysical computational tool that consists of an intuitive graphical user interface (GUI) and a database produced by numerical calculations. In this Website the user can make use of the existing numerical simulations from the database or run a new simulation introducing initial conditions such as temperatures, densities, velocities, and magnetic field intensities for both the ISM and HVC. The prototype is programmed using Linux, Apache, MySQL, and PHP (LAMP), based on the open source philosophy. All simulations were performed with the MHD code ZEUS-3D, which solves the ideal MHD equations by finite differences on a fixed Eulerian mesh. Finally, we present typical results that can be obtained with this tool.

TURBULENCE IN THE OUTSKIRTS OF THE MILKY WAY

  • Sanchez-Salcedo, F.J.;Santillan, A.;Franco, Jose
    • Journal of The Korean Astronomical Society
    • /
    • v.40 no.4
    • /
    • pp.171-177
    • /
    • 2007
  • In external galaxies, the velocity dispersion of the atomic hydrogen gas shows a remarkably flat distribution with the galactocentric radius. This has been a long-standing puzzle because if the gas velocity dispersion is due to turbulence caused by supernova explosions, it should decline with radius. After a discussion on the role of spiral arms and ram pressure in driving interstellar turbulence in the outer parts of galactic disks, we argue that the constant bombardment by tiny high-velocity halo clouds can be a significant source of random motions in the outer disk gas. Recent observations of the flaring of H I in the Galaxy are difficult to explain if the dark halo is nearly spherical as the survival of the streams of tidal debris of Sagittarius dwarf spheroidal galaxy suggests. The radial enhancement of the gas velocity dispersion (at R > 25 kpc) due to accretion of cloudy gas might naturally explain the observed flaring in the Milky Way. Other motivations and implications of this scenario have been highlighted.

Ceramium riosmenae sp. nov. (Ceramiaceae, Rhodophyta): a new complete corticated species on Gracilaria from Baja California Sur, Mexico

  • Won, Boo-Yeon;Cho, Tae-Oh
    • ALGAE
    • /
    • v.26 no.4
    • /
    • pp.289-297
    • /
    • 2011
  • Ceramium riosmenae sp. nov. is described from Baja California Sur, Mexico based on morphological and molecular data. The new species is characterized by erect thalli only, penetrating rhizoids on Gracilaria, 7-8 periaxial cells, five cortical initials per periaxial cell, complete cortication throughout, an average of 11-12 segments between branching points, rare adventitious branchlets, and cruciate tetrasporangia. Although C. riosmenae sp. nov. is similar to C. interruptum, C. sinicola, and C. codicola reported from Baja California Sur, Mexico in size and habit, it differs from these species in the number of cortical initials, habit, degree of cortication, host, and the shape of rhizoidal tips. C. riosmenae is separated from C. interruptum with interrupted cortication and four cortical initials from C. sinicola with spins near the apex and incomplete cortication near the base and from C. codicola with bulbous rhizoids on Codium. Our rbcL sequences reveal sufficient sequence divergence (2.4-3.9%) between C. riosmenae and C. interruptum, C. sinicola, and C. codicola to warrant species recognition and to separate C. riosmenae from these species on a phylogenetic tree.

Population Structure and Reproduction of Padina concrescens Thivy(Dictyotales: Phaeophyta) in Southwest Baja California Peninsula, Mexico

  • Rafael, Riosmena-Rodriguez;Consuelo, Ortuno-Aginrre
    • ALGAE
    • /
    • v.24 no.1
    • /
    • pp.31-38
    • /
    • 2009
  • The brown algae padina concrescens is widely distributed in the northwestern Pacific Mexico. We described the population of P. concrescens based on population parameters such as cover, density and size structure and reproduc-tion at two levels tide at the intertidal area in the southwestern Baja. California Peninsula. Monthly visits from January to December 2003 were done. Both cover and density were measured in situ by quadrants method. Samples were collected to obtain size structure and percentage of reproductive fronds. Our results show there is sparial vari-ation in the population structure more than temporal. Thus, cover and density peak were at different months ineach tide level studied, the lower tide level shows the high values in cover as well as density. The frond develop-ment was observed in height/width ratio this relation was consistent only in the low tidal zone. Size class distribu-tion has consistently small size plants in both tide levels.Reproduction was seasonal in the tide channel but in both tide levels all the reproductive plants were tetrasporophyte. Our results suggest that this population is pseudopere-nial and it strongly as a consequence of the intense competition in the intertidal zone.

nBn Based InAs/GaSb Type II Superlattice Detectors with an N-type Barrier Doping for the Infrared Detection

  • Kim, Ha-Sul;Lee, Hun;Hwang, Je-Hwan;Lee, Sang-Jun;Klein, B.;Myers, S.;Krishna, S.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.128.2-128.2
    • /
    • 2014
  • Long-wave infrared detectors using the type-II InAs/GaSb strained superlattice (T2SL) material system with the nBn structure were designed and fabricated. The band gap energy of the T2SL material was calculated as a function of the thickness of the InAs and GaSb layers by the Kronig-Penney model. Growth of the barrier material (Al0.2Ga0.8Sb) incorporated Te doping to reduce the dark current. The full width at half maximum (FWHM) of the 1st satellite superlattice peak from the X-ray diffraction was around 45 arc sec. The cutoff wavelength of the fabricated device was ${\sim}10.2{\mu}m$ (0.12eV) at 80 K while under an applied bias of -1.4V. The measured activation energy of the device was ~0.128 eV. The dark current density was shown to be $1.2{\times}10^{-5}A/cm^2$ at 80 K and with a bias -1.4 V. The responsivity was 1.9 A/W at $7.5{\mu}m$ at 80K and with a bias of -1.9V.

  • PDF

The Taxonomy of Psilocybe fagicola-complex

  • Guzmanl Gaston;Jacobs James Q.;Florencia Ramirez Guillenl;Murrietal Dulce;Gandaral Etelvina
    • Journal of Microbiology
    • /
    • v.43 no.2
    • /
    • pp.158-165
    • /
    • 2005
  • Psilocybe fagicola comprises a complex of more than eight species, six of them in Mexico, and all of them possessing a long pseudorhiza, a characteristic not listed by Heim and Cailleux in 1959 in the original description of the type species, but described by Guzman in 1978 and 1983. The description of Psilocybe fagicola s.s. is here emended to include the length of the cheilocystidia of(6-) 12-20 (-30) llm, as well as the absence or scarcity of pleurocystidia. Psilocybe xalapensis and P. wassoniorum are considered to be synonymous with P. fagicola s.s. However, Psilocybe banderillensis and P. herrerae from Mexico, P. columbiana from Colombia, and P. keralensis from India are considered to be valid species within this complex. Moreover, P. novoxalapensis and P. teofilae, both from Mexico, are described as new species. Length of spores, presence or absence of pleurocystidia and their variations, and type of cheilocystidia constitute the principal defining characteristics of the species. Setaceous hyphae at the base of the stipe, as well as caulocystidia, lack taxonomic value, as do other morphological characteristics, including pileipellis and subpileipellis. A key to the eight considered species is also presented within the paper.

Intestinal parasitic infections in the residents of an emigration camp in Tijiuana, Mexico (멕시코 티후아나 이민촌 거주자의 장내 기생충 감염 상태)

  • Sun HUH;Curie AHN;Jong-Yil CHAI
    • Parasites, Hosts and Diseases
    • /
    • v.33 no.1
    • /
    • pp.65-68
    • /
    • 1995
  • We examined stool specimens of the residents in the emigi·ation camp in Tijuana, Mexico for helminth eggs or protozoan cysts with formalin-ethyl acetate concentration method in February and July 1992. Out of 92 examined samples, number of positive was 49 (53.3%). While number of cumulative positive was 66 (71.7%). Cysts of Entnmoeba coli (29.3%) Giardio lomblia (9.8%), Entamoebo histolytica (7.6%), and eggs of Tqenic app. (6.5) were most frequently observed. Filtered water supply and chemotherapy were required in this camp.

  • PDF

Traditional Clothes in Mexico and Guatemala (과테말라와 멕시코의 민속의상 위필(Huipil)에 관한 고찰)

  • Kim Hee-Jung
    • Journal of the Korean Home Economics Association
    • /
    • v.43 no.3 s.205
    • /
    • pp.131-145
    • /
    • 2005
  • The purpose of the study was to determine ae forms, patterns and structures of Huipils as traditional clothes in Guatemala and Mexico, and to cite possibilities of applying the findings of the study, acquired by comparing the differences of the two countries' Huipils, to textile or costume design. There are two types of Huipils. One is for everyday wear and another one is for special occasion. The latter is bigger in size, more colorful and is worn on top of the daily use Huipil. Huipils consist of 1 to 3 panels, and are usually made by weaving rectangular cloth which has 4 selvedges. There are various neckline such as - type, T type, 1 type, round type and square type. The types of the neckline depends on how many panels are used. The Mexican Huipils are worn usually over skirts, whereas the Huipils of Guatemalans are practically designed with white cotton that doesn't have any patterns so as to be easily put into skirts. Different from Mexicans' Huipils which mainly show big botanical patterns, the patterns of Guatemalans' Huipils combine animals, plants and abstract concepts display mixed aspects, and it seems to me that that expressed their emotions and dearest wishes.