PDF superior Hundred-year changes in the avifauna of the Valley of Mexico, Distrito Federal, Mexico

Hundred-year changes in the avifauna of the Valley of Mexico, Distrito Federal, Mexico

Hundred-year changes in the avifauna of the Valley of Mexico, Distrito Federal, Mexico

García, Alejandro Gordillo, and very especially Claudia Abad and Rosa Salazar. Thanks also to Armando Butanda for providing access to the Historical collection at the Library of the Instituto de Biología, UNAM. The following scientific collections kindly made data and specimens available to us for study and use in this study: American Museum of Natural History; Academy of Natural Sciences of Philadelphia; Bell Museum of Natural History; British Museum (Natural History); California Academy of Sciences; Carnegie Museum of Natural History; Canadian Museum of Nature; Denver Museum of Natural History; Delaware Museum of Natural History; Fort Hays State College; Field Museum of Natural History; Iowa State University; University of Kansas; Los Angeles County Museum of Natural History; Natuurhistorische Museum; Louisiana State University Museum of Zoology; Museum of Comparative Zoology, Harvard University; Moore Laboratory of Zoology, Occidental College; Museum Nationale d’Histoire Naturelle; Museum of Vertebrate Zoology, Berkeley; Museo de Zoología, Facultad de Ciencias, Universidad Nacional Autónoma de México; University of Nebraska; Royal Ontario Museum; San Diego Natural History Museum; Southwestern College; Texas Cooperative Wildlife Collections; University of Arizona; University of British Columbia Museum of Zoology; University of California Los Angeles; Universidad Michoacana de San Nicolás de Hidalgo; United States National Museum of Natural History; Western Foundation of Vertebrate Zoology; and Peabody Museum, Yale University. This study was funded by CONACyT (R-27961), CONABIO (V-009), SEMARNAT-CONACYT Sectorial Funds C01-0265, and PAPIIT-UNAM (IN-214200 and 233002).
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Historical data and genetic diversity of poinsettia (Euphorbia pulcherrima) in the Distrito Federal, Mexico

Historical data and genetic diversity of poinsettia (Euphorbia pulcherrima) in the Distrito Federal, Mexico

Poinsettia (Euphorbia pulcherrima) is one of the most economically and culturally important ornamental plants in the world because it is the floral symbol of Christmas. However, little is known about its domestication, genetic diversity and history. This paper analyses the genetic diversity of plants grown in gardens and parks of the Distrito Federal, Mexico, and we compare it with that found in wild populations to document the genetic diversity of poinsettia represented in the Distrito Federal and its relationship to the plant’s origin. The plants found in the Distrito Federal are 2 genetic variants or haplotypes. One of these variants belongs to the state of Guerrero and the other belongs to a variant closely related to wild populations of Guerrero and Morelos. Historical documents show that since the Pre-Hispanic era, poinsettias were grown in central Mexico and in a manuscript from 1801 poinsettias are illustrated in the gardens of New Spain with modifications as compared to wild plants. The recognition of the genetic diversity of cultivated plants will allow the protection, sustainable management, conservation and genetic improvement of Mexican poinsettia germplasm.
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The algal flora of the river La Magdalena, Distrito Federal, Mexico

The algal flora of the river La Magdalena, Distrito Federal, Mexico

Datos ecológicos: perifítica, epilítica, epífita, desliza- miento, remanso.. Referencias para México: primer registro.[r]

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Review of Gomphotheriidae in the late Cenozoic of Mexico

Review of Gomphotheriidae in the late Cenozoic of Mexico

Las colecciones que se revisaron, cuyos acrónimos se señalan entre paréntesis, fueron: en la Universidad Nacional Autónoma de México, la del Instituto de Geología incluidos los materiales depositados en el Museo de Geología de la mis- ma Universidad [MGUNAM, IGM, IGCU, LACM(CIT)]; en el Instituto Nacional de Antropología e Historia, la del Laboratorio de Arqueozoología en el Distrito Federal (DP), al que pertenecen también la del Museo Regional de Guadalajara (MRG) y la del Museo Regional de Puebla (MRP) y la del Centro Regional de Puebla (CRINAHP). Otra colección visitada fue la del Museo de Paleontología de Guadalajara “Ing. Federico Solórzano” (MPG), dependiente del ayuntamiento de esa ciudad. En el texto, los ejemplares son referidos de acuerdo al acrónimo de cada colección y a su número, sin embargo, cuando algunos de ellos no poseían número, se les agregaron las iniciales SN.
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Fluid geochemistry of the epithermal deposits in the southeastern part of the Temascaltepec District, Mexico State, Mexico

Fluid geochemistry of the epithermal deposits in the southeastern part of the Temascaltepec District, Mexico State, Mexico

This study is focused on the genetic relationship between different zones containing epithermal veins in the Temascaltepec mining district. For this purpose, the characteristics of their respective mineralizing fluids contained in fluid inclusions, stable isotope geochemistry, and spectrometric volatile analyses of fluid inclusions were used. The Temascaltepec district is located 150 km south- east of Mexico City, in Mexico state, and is constituted by several Ag–Au bearing low–sulfidation epithermal veins. In this area, three main vein sets occur from NW to SE: (1) El Coloso, (2) La Guitarra, which laterally connects to El Coloso, and (3) Mina de Agua, comprising over 50 known veins with dominant NW–SE orientation. These three vein sets are hosted by three different litho- logic units: Eocene volcanic rocks, Paleocene monzogranites, and pre–Albian metamorphic rocks, respectively.
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Evolution of the electricity sector in Mexico

Evolution of the electricity sector in Mexico

Nowadays, the running of a company, installed before the Reform, has not changed a lot, unless the company has decided to take part of the market. The normal situation is to continue with its normal activity but analysing and studying the new system and the possible consequences and advantages that it can have in the company. In 2016, generators and clients go to the market to learn how to operate on it, rather than considering that it is the best option, because in 2018 the market will be completely liberalised and companies will need to know how to move on it. Mexico has design a complicated electric system and it will take time to have everything in its place. Meanwhile, companies should train their workers and prepare the tools and mechanism to deal with the new items.
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The Social Relevance of Nanotechnology in Mexico

The Social Relevance of Nanotechnology in Mexico

The third aspect is the generation of high-level human resources to satisfy demand in the NT sector. NT is a technology that transcends the limits of the scientific disciplines. One must understand physics, chemistry, materials, optics and other areas in order to know how to take advantage of its potential at the molecular level. Mexico trains about three-thousand PhDs per year (across all areas of knowledge), while Brazil prepares 11-thousand and the USA 50- thousand in the same period (Drucker, 2012). This is where the scientific infrastructure deficit occurs, which means the few who manage to undertake high-level research or obtain an academic degree abroad, above all in the natural sciences and engineering, end up unemployed since there is no place where they can apply what they have learned. As a consequence, for example, there are more Mexican PhDs in the USA than in the National System of Researchers (SNI) of CONACYT: 20-thousand vs. 16-thousand (Melesio, 2011).
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The incidence of agricultural subsidies in Mexico

The incidence of agricultural subsidies in Mexico

These estimates of course only consider the direct, first-order incidence of the benefits from APE. In a general equilibrium setting, agricultural workers and small land owners may share some of the benefits from the agricultural support transfers obtained by large commercial producers, through higher wages and land prices. However, there are at least two reasons to doubt that such “trickle-down” effects would be sufficient to reverse the first-order effect. First, as we have seen, the large, grain-producing commercial farms in the northern states benefiting from these transfers tend to be capital- rather than labor-intensive. Secondly, by further increasing the cost-advantage of large-scale producers, these transfers undermine the capacity of small (potentially) commercial producers to compete in these markets. Note that the argument to support these smaller but viable farmers is exactly analogous to the argument often used in favor of supporting the larger commercial producers to compensate them for unfair competition due to international subsidies.
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View of Edaphic changes in fertility islands and their importance for performance of an ecosystem in the Tehuacan Valley, Puebla, Mexico

View of Edaphic changes in fertility islands and their importance for performance of an ecosystem in the Tehuacan Valley, Puebla, Mexico

No obstante que no se presentaron diferencias signif icativas en el índice de calidad total de los suelos tanto dentro como fuera de las IF, al analizar de manera individualiza[r]

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Species of Cyperaceae recorded the first time for the flora of the Valley of Mexico and the Mexican Republic

Species of Cyperaceae recorded the first time for the flora of the Valley of Mexico and the Mexican Republic

Las especies citadas por primera vez par.a l a República Mexicana son Carex brachycalama, Scirpus nevadensis y Uncinia phleoides.. A continuación se proporcionan alg[r]

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The implementation of the clean development mechanism in Mexico

The implementation of the clean development mechanism in Mexico

J\rticle 12 of the Kyoto Protocol establishes the Clean Developmenl Mechanism to contribute to sustainablc developmcnt of the host country and to help J\nnex I parties meet their emissio[r]

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The history of herpetological exploration in Mexico

The history of herpetological exploration in Mexico

Abstract. The earliest recorded exploration of the herpetofauna of Mexico was that of Francisco H ERNÁNDEZ , 1570– 1577. No specimens are known to have been collected; his accounts, published in 1648, were strictly descriptive and pictorial, few are reliably identifiable. Two centuries later, 1788–1803, the much less publicized but botanically more important S ESSÉ & M OCIÑO expedition from Spain secured incidentally a small amount of herpetological material, al- though none of it was reported. The earliest preserved collections were made by Ferdinand D EPPE in 1824–1825. Nu- merous scattered collections were made in subsequent decades, all shipped to foreign countries for study. Not until Al- fredo D UGÈS started a collection at the University of Guanajuato in 1853–1910 was there much of an effort to develop domestic resources for herpetological study. Most work remained in foreign hands even then and well into the 20th cen- tury, but it was scattered and sporadic until 1892–1906, when N ELSON and G OLDMAN initiated the most thoroughly or- ganized, protracted survey of the country ever undertaken up to that time. G ADOW followed with moderately extensive collections in 1902 and 1904. Between the 1930s and 1960s there was an explosion of foreign collecting in Mexico, reaching such magnitude that federal levies and permits were exacted to stem the flow. These actions were highly suc- cessful, and as a result relatively little foreign collecting now takes place. On the contrary, domestic activity has greatly increased. The approximate state of knowledge of the herpetofauna of each state is briefly reviewed. The limits of her- petozoan diversity and distribution in Mexico are not closely approached, however, even after five centuries of study, and will continue to attract attention for decades yet to come.
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Decades of Experience in the Diagnosis of Dengue Fever in the Northwest of Mexico

Decades of Experience in the Diagnosis of Dengue Fever in the Northwest of Mexico

ies suggest that a greater attention to the adult pop- ulation may help in reducing a serious loss of financial resources for working adults during their illness. A different age group appears to be more vulnerable in some nations. In the last 10 years, Brazil, Colombia, Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua experienced a higher incidence among chil- dren 27 . This has also been reported for Thailand, where

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View of The development of human resource in the tourism sector of Mexico

View of The development of human resource in the tourism sector of Mexico

This paper aims to analyze the development of human resources in the Mexican tourism sector. This industry has contributed significantly in the progress of the economy. However, little development of human resources has been observed, many jobs are not well paid. Statistical data were analyzed in the period from 2008 to 2013. The information was taken from reports of the National Employment Service, Labor Observatory and the Ministry of Labor and Social Welfare bodies. The results show that the population employed in the tourism sector represents around three million people; most of them have primary and secondary education, while a minority with university studies. In the year 2008, most of the population had primary education, and a smaller amount with higher education. During 2009, the average monthly income was the smallest of the period studied. With respect to the employment position, in 2012 the lowest amount of population occupied in management positions was observed. In conclusion, the Mexican government needs to develop a set of public policies that allow the development of human capital in the Mexican tourism sector.
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The use of oak in the region of La Malinche, State of Tlaxcala, Mexico.

The use of oak in the region of La Malinche, State of Tlaxcala, Mexico.

La madera de encino es utilizada de forma local para l a e l aboración de manceras de arado, cabos para hachas, zapapicos, hoces y palas, ya que su dureza l e confiere [r]

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Chemical species of chromatite of an industrial landfi ll in the  León valley, Guanajuato, Mexico

Chemical species of chromatite of an industrial landfi ll in the León valley, Guanajuato, Mexico

Chromium occurs naturally at trace levels in most soils and water, but disposal of industrial waste and sew- age sludge containing chromium compounds has created a number of contaminated sites. Their determination requires the application of a suffi ciently sensitive method, but its specificity has an important role to play in the case of chemical individuals or its selectivity in regard to speciation of a group of compounds, e.g., valency states or organic chromium complexes (Świetlik, 1998). Background levels correspond to the total concentrations of metals in soil not affected by human activities. These values have been reported by many authors (e.g., Alloway, 1995; Archer and Hodgson, 1987) and a number of guidelines exist to establish the maximum levels of heavy metals in soils (Council of the European Communities, 1986; U.S. EPA, 1993). Total concentrations of chromium (Cr) in soils range from 9.9 to 121 μg/g (Archer and Hodgson, 1987; ASTM, 2000). Chromium is not present in elemental form and its main source is chromite (FeCr 2 O 4 ).
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The floristic knowledge of Mexico

The floristic knowledge of Mexico

Esta evaluación está basada en un análisis del número de colecciones botánica s y de herbarios, así como en los estudios florísticos concluidos y en desarrollo que exis[r]

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View of Maize production and pluriactivity in peasants in the Valley of Puebla, Mexico
							| Nova Scientia

View of Maize production and pluriactivity in peasants in the Valley of Puebla, Mexico | Nova Scientia

ha, el 9.0 % posee de 3.25 a 6.0 ha y el 0.9% posee un máximo de 11 ha, lo cual evidencia que el minifundio es imperante en la región. Este resultado evidencia una tendencia a la fragmentación de la tierra, posiblemente porque se ha continuado con la cultura de heredar las parcelas a los descendientes. El nivel de fragmentación está en función del número de hijos que tiene la familia (López 2001, 36). Este dato contrasta con lo reportado por Díaz et al. (1999, 21) quienes indicaban que en el Valle de Puebla, el promedio de superficie por agricultor en 1967 era de 2.47 hectáreas y, que para 1982 presentaba un incremento, alcanzando en promedio 5.05 ha. Cabe mencionar que según Artís (1997, 4) Puebla es uno de los estados del país con minifundio extremo, pues la superficie promedio de los productores es menor de cinco hectáreas, y que el Distrito de Desarrollo Rural de Cholula es uno de los que se encuentran en situación más crítica a nivel país, pues el promedio reportado es de 2.2 hectáreas por agricultor.
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View of Impact of tourism in the hoteles in Mexico

View of Impact of tourism in the hoteles in Mexico

Tourism is an important activity in the world economy, which implies the displacement from one place to another, and thanks to it, a country is modernizing and developing infrastructure to offer quality tourist services in demand; Mexico is one of the main tourist destinations in the world because you can perform all kinds of tourist activities such as: cultural, sports, religious, eco-tourism, wellness, medical, adventure, gastronomic among others with its international travelers such as international tourists with internment and border tourists, international hikers with border and cruise hikers. The objective of this research is to analyze the impact of tourism in hospitality in Mexico through a descriptive methodology through an analytical review of the literature with secondary sources. It is concluded that the hotel infrastructure has increased in recent years due to the increase in the flow of tourists both national and international, which represents the growth in foreign exchange income, jobs and investment for this activity.
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Epigenesis of the journalism about the narco in Mexico

Epigenesis of the journalism about the narco in Mexico

- Qué hace una agente de la DEA inmediatamente después de ser asignado a México? Mike Vigil, quien posiblemente es uno de los ex agentes de la DEA con mayor experiencia en materia de investigación en México, hace una pequeña pausa antes de contestar. -Tener contacto con las autoridades mexicanas y armar una buena red de informantes para penetrar a los cárteles del lugar en donde te hayan asignado. Un informante de la DEA puede ser un policía municipal, estatal o federal, corrompido por el narcotráfico; un vendedor de periódicos que conoce todos los movimientos criminales de la colonia o del barrio, o bien cualquier persona. Pero la fuente secreta más valiosa de una agente estadounidense es un integrante del crimen organizado y/o de algún cártel de las drogas. En otras palabras, el informante ideal para un agente antinarcóticos de Estados Unidos es un criminal (Esquivel, 2014: 27).
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