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Mexico
Kinds of Mexico Terms modified by Mexico Selected Abstracts[Commentary] POOR MEXICO: SO FAR AWAY FROM GOD, SO CLOSE TO THE UNITED STATESADDICTION, Issue 4 2009RAUL CAETANO No abstract is available for this article. [source] A SHORTAGE OF MEDICAL DOCTORS TO MEET THE CHALLENGES OF A GROWING ADDICTION PROBLEM IN LOW AND MIDDLE INCOME COUNTRIES: THE CASE IN MEXICOADDICTION, Issue 2 2009MARIA ELENA MEDINA-MORA No abstract is available for this article. [source] ON THE GEOCHRONOLOGICAL METHOD VERSUS FLOW SIMULATION SOFTWARE APPLICATION FOR LAHAR RISK MAPPING: A CASE STUDY OF POPOCATÉPETL VOLCANO, MEXICOGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2010ESPERANZA MUÑOZ-SALINAS ABSTRACT. Lahars are hazardous events that can cause serious damage to people who live close to volcanic areas; several were registered at different times in the last century, such as at Mt St Helens (USA) in 1980, Nevado del Ruiz (Colombia) in 1985 and Mt Pinatubo (Philippines) in 1990. Risk maps are currently used by decision-makers to help them plan to mitigate the hazard-risk of lahars. Risk maps are acquired based on a series of tenets that take into account the distribution and chronology of past lahar deposits, and basically two approaches have been used: (1) The use of Flow Simulation Software (FSS), which simulates flows along channels in a Digital Elevation Model and (2) The Geochronological Method (GM), in which the mapping is based on the evaluation of lahar magnitude and frequency. This study addresses the production of a lahar risk map using the two approaches (FSS and GM) for a study area located at Popocatépetl volcano , Central Mexico. Santiago Xalitzintla, a town located on the northern flank of Popocatépetl volcano, where volcanic activity in recent centuries has triggered numerous lahars that have endangered local inhabitants, has been used for the case study. Results from FSS did not provide satisfactory findings because they were not consistent with lahar sediment observations made during fieldwork. By contrast, the GM produced results consistent with these observations, and therefore we use them to assess the hazard and produce the risk map for the study area. [source] A JÖKULHLAUP FROM A LAURENTIAN CAPTURED ICE SHELF TO THE GULF OF MEXICO COULD HAVE CAUSED THE BØLLING WARMINGGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 2 2008ULF ERLINGSSON ABSTRACT. Since the rapid rate of global warming at the onset of the Bølling interstadial became evident, its cause has been under debate. It coincides closely in time with a strong global transgression called meltwater pulse 1a. One attempt at solution says that a meltwater pulse of Antarctic origin could cause an increase in North Atlantic Deep Water formation, and thus give rise to the Bølling interstadial. However, others have disputed that Antarctic meltwater would have that effect, and furthermore, the start of the Bølling interstadial is not even associated with an increase in North Atlantic Deep Water. A controversial hypothesis says that some Laurentian meltwater came from a jökulhlaup (sub-glacial outburst flood), but no study has yet shown unequivocally that sufficient amounts of water could be stored under the ice. Furthermore, according to all available data a melt-water pulse from the Laurentian ice would give rise to strong cooling, not warming. Nevertheless, meg-afloods appear instrumental in accumulating the Mississippi Fan, created entirely during the Quaternary period, and dramatic climate changes are characteristic of this period. This paper presents a hypothetical chain of events, building on the published literature and simple calculations, to investigate whether the order of magnitude is reasonable. The hypothesis is that a jökulhlaup from a Laurentian captured ice shelf flowed out through the Mississippi, boosted the Gulf Stream, reinvigorated the North Atlantic circulation, and as a result triggered the Bølling warm phase. [source] EXPLORING MARKET-BASED DEVELOPMENT: MARKET INTERMEDIARIES AND FARMERS IN CALAKMUL, MEXICO,GEOGRAPHICAL REVIEW, Issue 1 2005ERIC KEYS ABSTRACT. Market intermediaries play important roles in the development of tropical-forest frontiers but are often overlooked in the assessment of land-change dynamics. Consistent with research beyond land-change studies, intermediaries are found to be a pivotal element in land-use and land-cover change in southeastern Mexico. They have stimulated commercial chili cultivation in this development frontier, providing transportation and other services to smallholders who could otherwise not enter the chili market. This role comes at the cost of a near monopoly on chili marketing. The various roles played by these intermediaries, or coyotes, the means by which they operate, and the consequences for smallholders and land use are detailed for the Calakmul Municipality, Campeche, Mexico. [source] MUEBLES RÚSTICOS IN MEXICO AND THE UNITED STATESGEOGRAPHICAL REVIEW, Issue 3 2002Article first published online: 21 APR 2010, JOHN HARNER ABSTRACT. Sales of muebles rústicos, or rustic wooden furniture made in Mexico, have grown rapidly in the United States since 1994. Analysis of the recent rise of the industry tracks manufacturing and marketing methods in major production areas of Mexico. Consumer taste for "authentic" handmade goods of simple design and the vogue of the "Santa Fe" style across the American Southwest mesh with Mexican producers' need to seek foreign markets during an economic crisis. Changing style preferences, along with the furniture's handcrafted appearance, its competitive cost, and the makers' flexible production methods, are reasons for the increased popularity of this folk commodity. [source] ALKALOID COMPOSITION OF LUPINUS CAMPESTRIS FROM MEXICOJOURNAL OF FOOD BIOCHEMISTRY, Issue 2 2001J. MARTÍNEZ-HERRERA ABSTRACT The content of quinolizidine alkaloids (QA) in Lupinus campestris, Fabaceae family, was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS), Samples of various organs of Lupinus campestris collected at different monthly stages of the growing plant, were subjected to extraction in a Merck Extrelut column. The quinolizidine alkaloid patterns of stems, leaves, flowers, pods and seeds were assessed and then identified and quantified by GC. Alkaloid structures were identified according to their mass fragmentation patterns, in combination with their indicative Kovats retention index. Alkaloids found in several developmental stages of the plant were mainly: aphyllidine, 5, 6-dehydrolupanine, aphylline, dehydro-oxosparteine, lupanine, ,-isolupanine, hydroxyaphylline and hydroxyaphyllidine, plus two alkaloids that -were not identified. During the third month the relative abundance of total alkaloids were highest. The main alkaloids found in seeds were hydroxyaphylline and hydroxyaphyllidine. [source] USING MEXICO AND ROMANIA AS FOCUS COUNTRIES TO ADD DEPTH TO AN INTERNATIONAL BUSINESS LAW COURSEJOURNAL OF LEGAL STUDIES EDUCATION, Issue 1 2000Paulette L. Stenzel [source] CYLINDRICAL AND CONICAL FOLD GEOMETRIES IN THE CANTARELL STRUCTURE, SOUTHERN GULF OF MEXICO: IMPLICATIONS FOR HYDROCARBON EXPLORATIONJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2006J. J. Mandujano V. The NW-SE trending Cantarell structure in the Gulf of Campeche hosts the largest oilfield in Mexico. The oil occurs predominantly in latest Cretaceous , earliest Tertiary breccias with subsidiary reserves in Upper Jurassic (Oxfordian and Kimmeridgian) and Lower Cretaceous oolitic and partially dolomitized limestones, dolomites and shaly limestones. Cantarell has been interpreted both as a fold-and-thrust zone and as a dextral transpressional structure. Analysis of structure contours at 100m intervals, on the tops of the Tertiary breccia and the Kimmeridgian (Upper Jurassic) dolomite, indicates that the structure is an upright cylindrical fold with gently plunging conical terminations; there is also a conical portion in the central part of the structure. The axes of the central, NW and SE cones are subvertical. This geometry indicates that the two fold terminations and the central cone are aprons rather than points, with the NW and central cone axes intersecting the cylindrical fold axis at the point where the geometry switches from conical to cylindrical. The apical angle (i.e. the angle between the fold and cone axes) varies as follows: (i) in the NW cone, it is ,70° in the breccia and ,76° in the Kimmeridgian dolomite; (ii) in the central cone, it is ,77° in the breccia and ,73° in the Kimmeridgian dolomite; and (iii) in the SE cone, it is ,64° in the breccia and ,57° in the Kimmeridgian dolomite. This indicates that whereas the fold opens with depth in the NW cone, it tightens with depth in the central and SE cones. Assuming a parallel fold geometry, these apical angles indicate an increase in volume in the NW cone (i.e. larger hydrocarbon reservoirs), compared to the central and SE cones. Theoretical considerations indicate that the curvature increases dramatically towards the point of the cone. In the case of the Cantarell structure, the apices of the cones are located at the conical-cylindrical fold junctions, where the highest curvature may have resulted in a higher degree of fracturing. The coincidence of maximum curvature and the intersection of the conical and cylindrical fold axes in the fold culminations with porous and permeable reservoir rocks may have made these locations favourable for the accumulation of hydrocarbons. [source] MARINE ALGAE ASSOCIATED WITH CARIBBEAN ROCKY SHORES, QUINTANA ROO, MEXICOJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Albert, E. M. & Lehman, R. L. Center for Coastal Studies, Texas A&M University-Corpus Christi, Corpus Christi, TX 78412 USA Rocky shores located on the east coast of the Yucatan Peninsula are typically high-energy habitats associated with fringing or barrier reef systems. They are phytokarstic (iron-shore) consisting of fossiliferous limestone that is composed of stony coral skeletons. This study compares the macroalgae from three rocky shores located on the east coast of the Yucatan Peninsula, Quintana Roo, Mexico. Fifteen 0.25m2 quadrates were randomly placed in the intertidal and subtidal zones and evaluated for dominant algal cover. In addition, fifteen 0.25 m2 quadrates of standing stock material was randomly collected and used to characterize algal composition, species richness, abundance, and biomass. A voucher collection including herbarium mounts and preserved specimens were prepared for all species encountered. Thirty-five species were identified representing three divisions: Rhodophyta, Chlorophyta, and Phaeophyta. Rhodophyta had the highest species richness with a total of fifteen taxa identified. Phaeophyta had the lowest species richness with seven taxa but dominated algal coverage at two of the three sites. Chlorophyta was represented by thirteen species. Species common to all points were represented by Digenia simplex, Laurencia poiteaui, Laurencia sp., Polysiphonia sp., Microdictyon marinum, Halimeda opuntia, Dictyosphaeria cavernosa, Padina sanctae-crucis, and Turbinaria tricostata. [source] PHYLOGENETIC AND BIOGEOGRAPHIC AFFINITIES OF THE HALYMENIALES AND RHODYMENIALES (RHODOPHYTA) FROM THE GULF OF MEXICOJOURNAL OF PHYCOLOGY, Issue 2000B. Gavio Generic and species concepts within the red algal assemblages Halymeniales and Rhodymeniales are discussed for taxa inhabiting the western Gulf of Mexico. Two principal biogeographic assemblages occur: an off-shore deep-water group (including Coelarthrum cliftonii, Halymenia spp., Botryocladia spp., Gloiocladia) representing remnants of a Tethyan distribution, and a near-shore intertidal flora (comprising Rhodymenia, Grateloupia and Prionitis) which instead reveals biogeographic affinities with the Carolinian Province. These two distinct marine floras will be contrasted phylogenetically based on DNA sequence analysis inferred from chloroplast-encoded rbcL. The generic descriptions of Grateloupia and Prionitis are in need of taxonomic revision based on a survey of species from Caribbean and Pacific Mexico. [source] GLOBAL SYSTEMATIC AND PHYLOGENETIC ANALYSIS OF SARGASSUM IN THE GULF OF MEXICO, CARIBBEAN AND PACIFIC BASINJOURNAL OF PHYCOLOGY, Issue 2000N. Phillips Sargassum is one of the most species-rich genera in the brown algae with over 400 described species worldwide. The bulk of these species occurs in Pacific-Indian ocean waters with only a small portion found on the Atlantic side of the Isthmus of Panama. Sargassum also has one of the most subdivided and complex taxonomic systems used within the algae. Systematic distinctions within the genus are further complicated by high rates of phenotypic variability in several key morphological characters. Molecular analyses in such systems should allow testing of systematic concepts while providing insights into speciation and evolutionary patterns. Global molecular phylogenetic analyses using both conserved and variable regions of the Rubisco operon (rbcL and rbcL-IGS-rbcS) were performed with species from the Gulf of Mexico, Caribbean, and Pacific basin. Results confirm earlier analyses based on rbcL-IGS- rbcS from Pacific species at the subgeneric and sectional level while providing additional insights into the systematics and phylogenetics on a global scale. For example, species east of the Isthmus of Panama form a distinct well-resolved clade within the tropical subgenus. This result in sharp contrast to traditional systematic treatments but provides a window into the evolutionary history of this genus in the Pacific and Atlantic Ocean basins and a possible means to time speciation events. [source] GRAY WHALEs' MID-SPRING FEEDING AT BAHÍA DE LOS ÁNGELES, GULF OF CALIFORNIA, MEXICOMARINE MAMMAL SCIENCE, Issue 1 2001JoséÁngel Sánchez-Pacheco [source] SHORT-RUN AND LONG-RUN DETERMINANTS OF THE REAL EXCHANGE RATE IN MEXICOTHE DEVELOPING ECONOMIES, Issue 1 2008Antonia LÓPEZ VILLAVICENCIO C32; F31; F41; F49 This paper explores the real exchange rate behavior in Mexico from 1960 until 2005. Since the empirical analysis reveals that the real exchange rate is not mean reverting, we propose that economic fundamental variables affect its evolution in the long run. Therefore, based on equilibrium exchange rate paradigms, we propose a simple model of real exchange rate determination, which includes the relative GDP per capita, the real interest rates, and the net foreign assets over a long period of time. Our analysis also considers the dynamic adjustment in response to shocks through impulse response functions derived from the multivariate vector autoregressive (VAR) model. [source] TIME-VARYING ESTIMATES ON THE OPENNESS OF CAPITAL ACCOUNTS IN EAST ASIA AND MEXICOTHE DEVELOPING ECONOMIES, Issue 2 2000Sun LIXING First page of article [source] PROVENANCE OF THE LIMESTONE USED IN TEOTIHUACAN (MEXICO): A METHODOLOGICAL APPROACH,ARCHAEOMETRY, Issue 4 2009L. BARBA This work shows the preliminary results of an international project for the interdisciplinary study of the limestone used in the plasters of the ancient city of Teotihuacan. The limestone provenance was studied using a new approach based on the chemical analysis of the lime lumps that were selected because they represent the composition of the original limestone rock. The results show that the applied methodology was successful and that the limestone used to produce the lime employed to make the floor of the main courtyard at Teopancazco (Teotihuacan), comes from the region near Tula (Hidalgo). [source] TESTING ASSUMPTIONS OF NEUTRON ACTIVATION ANALYSIS: COMMUNITIES, WORKSHOPS AND PASTE PREPARATION IN YUCATAN, MEXICO,ARCHAEOMETRY, Issue 2 2000D. E. ARNOLD Contemporary pottery and raw materials (N= 170) from three workshops in Ticul, Yucatán, were analysed by neutron activation to test the hypothesis that individual workshops that used their own clay sources could be identified by their pottery. Although the data failed to confirm the hypothesis, the results reinforced previous conclusions about the relationship of local communities of potters to the chemical patterning of pottery made in these communities. [source] AVANT-GARDE AESTHETICS AND NATIONHOOD: THE CULTURAL HISTORY OF POST-REVOLUTIONARY MEXICO (1920,1950) by Mary Kay Vaughan, Stephen E. Lewis and Rubén GalloART HISTORY, Issue 3 2009Fabiola Martínez Rodríguez First page of article [source] Towards an integrated GIS-based coastal forecast workflowCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 14 2008Gabrielle Allen Abstract The SURA Coastal Ocean Observing and Prediction (SCOOP) program is using geographical information system (GIS) technologies to visualize and integrate distributed data sources from across the United States and Canada. Hydrodynamic models are run at different sites on a developing multi-institutional computational Grid. Some of these predictive simulations of storm surge and wind waves are triggered by tropical and subtropical cyclones in the Atlantic and the Gulf of Mexico. Model predictions and observational data need to be merged and visualized in a geospatial context for a variety of analyses and applications. A data archive at LSU aggregates the model outputs from multiple sources, and a data-driven workflow triggers remotely performed conversion of a subset of model predictions to georeferenced data sets, which are then delivered to a Web Map Service located at Texas A&M University. Other nodes in the distributed system aggregate the observational data. This paper describes the use of GIS within the SCOOP program for the 2005 hurricane season, along with details of the data-driven distributed dataflow and workflow, which results in geospatial products. We also focus on future plans related to the complimentary use of GIS and Grid technologies in the SCOOP program, through which we hope to provide a wider range of tools that can enhance the tools and capabilities of earth science research and hazard planning. Copyright © 2008 John Wiley & Sons, Ltd. [source] Beyond drug wars: Transforming factional conflict in MexicoCONFLICT RESOLUTION QUARTERLY, Issue 4 2010Ami C. Carpenter Blurring the lines between criminal and civil war, factional conflict in Mexico has escalated since 2006 and claimed more than eleven thousand lives. This article assesses the viability of Mexico's military offensive against the nation's drug cartels by analyzing the effects of this strategy on destructive conflict escalation. It is argued that the enforcement strategy of arresting key druglords has become a proximate factor in escalating Mexico's violence by promoting intercartel competition and intensifying leadership struggles. A set of viable third-party alternatives to the "war on drugs" is explored. [source] Effects of Conversion of Dry Tropical Forest to Agricultural Mosaic on Herpetofaunal AssemblagesCONSERVATION BIOLOGY, Issue 2 2008IRERI SUAZO-ORTUÑO atributos de vulnerabilidad; bosque tropical seco; ensambles herpetofaunísticos; modificación del hábitat; mosaico agrícola Abstract:,We explored the impact of forest conversion to agricultural mosaic on anuran, lizard, snake, and turtle assemblages of Neotropical dry forests. Over 2 years, we sampled 6 small watersheds on the west coast of Mexico, 3 conserved and 3 disturbed. The disturbed watersheds were characterized by a mosaic of pastures and cultivated fields (corn, beans, squash) intermingled with patches of different successional stages of dry forest. In each watershed, we conducted 11 diurnal and nocturnal time-constrained searches in 10 randomly established plots. We considered vulnerability traits of species in relation to habitat modification. Eighteen anuran, 18 lizard, 23 snake, and 3 turtle species were recorded. Thirty-six species (58%) occurred in both forest conditions, and 14 (22%) and 12 species (19%) occurred only in the conserved and disturbed sites, respectively. Assemblages responded differently to disturbance. Species richness, diversity, and abundance of lizards were higher in disturbed forests. Anuran diversity and species richness were lower in disturbed forest but abundance was similar in both forest conditions. Diversity, richness, and abundance of turtles were lower in disturbed forest. The structure and composition of snake assemblages did not differ between forest conditions. We considered species disturbance sensitive if their abundance was significantly less in disturbed areas. Four anuran (22%), 2 lizard (11%), and 3 turtle (100%) species were sensitive to disturbance. No snake species was sensitive. The decline in abundance of disturbance-sensitive species was associated with the reduction of forest canopy cover, woody stem cover, roots, and litter-layer ground cover. Anuran species with small body size and direct embryonic development were especially sensitive to forest disturbance. An important goal for the conservation of herpetofauna should be the determination of species traits associated with extinction or persistence in agricultural mosaics. Resumen:,Exploramos el impacto de la conversión de bosques a mosaico agrícola sobre ensambles de lagartijas, serpientes y tortugas de bosques Neotropicales secos. Durante 2 años muestreamos 6 cuencas pequeñas, 3 conservadas y 3 perturbadas, en la costa occidental de México. Las cuencas perturbadas se caracterizaron por un mosaico de pastizales y campos cultivados (maíz, frijol, calabaza) entremezclados con parches de bosque seco en diferentes etapas sucesionales. En cada cuenca, realizamos 11 búsquedas diurnas y nocturnas en 10 parcelas establecidas aleatoriamente. Consideramos los atributos de vulnerabilidad de especies en relación con la modificación del hábitat. Registramos 18 especies de lagartijas, 23 de serpientes y 3 de tortugas. Treinta y seis especies (58%) ocurrieron en ambas condiciones de bosque, y 14 (22%) y 12 (19%) especies solo ocurrieron en los sitios conservados y perturbados, respectivamente. Los ensambles respondieron a la perturbación de manera diferente. La riqueza de especies, la diversidad y la abundancia de lagartijas fueron mayores en los bosques perturbados. La diversidad y riqueza de especies de anuros fueron menores en el bosque perturbado pero la abundancia fue similar en ambas condiciones de bosque. La diversidad, riqueza de especies y abundancia de tortugas fueron menores en el bosque perturbado. La estructura y la composición de los ensambles de serpientes no difirieron entre condiciones de bosque. Consideramos que las especies eran sensibles a la perturbación si su abundancia fue significativamente menor en las áreas perturbadas. Cuatro (22%) especies de anuros, 2 (11%) de lagartijas y 3 (100%) de tortugas fueron sensibles a la perturbación. Ninguna especie de serpiente fue sensible. La declinación en la abundancia de especies sensibles a la perturbación se asoció con la reducción en la cobertura del dosel, de tallos leñosos, raíces y hojarasca. Las especies de anuros de cuerpo pequeño y desarrollo embrionario directo fueron especialmente sensibles a la perturbación del bosque. La determinación de atributos de las especies asociadas con su extinción o persistencia en mosaicos agrícolas debería ser una meta importante para la conservación de la herpetofauna. [source] Shade-Coffee Plantations as Refuges for Tropical Wild Orchids in Central Veracruz, MexicoCONSERVATION BIOLOGY, Issue 3 2005LISLIE SOLIS-MONTERO biología reproductiva; epifitas vasculares; estratificación vertical; estructura poblacional; limitación de polinizador Abstract:,In central Veracruz, Mexico, coffee plantations have replaced large areas of lower montane cloud forest. Shade-coffee plantations with high levels of structural diversity provide refuge for forest-dependent biota (e.g., birds and insects). Orchids typical of natural forest may also be found in the canopy of shade-coffee agroecosystems. It is not known, however, whether these are relicts from the original forest vegetation or if the plantations themselves provide the necessary conditions to support a self-sustained orchid population. We studied the population structure of the epiphytic orchids Jacquiniella teretifolia (Sw.) Britton & Willson, Scaphyglottis livida (Lindl.) Schltr., and Maxillaria densa Lindl. in a shade-coffee plantation (commercial polyculture) in central Veracruz. We also studied the previously undescribed reproductive biology of the latter two species. Our results show that the three orchid species had high population densities (>800 plants/ha). In our study site, 50% to 68% of the orchid plants of the target species were young individuals (less than five shoots). Reproductive structures were present in 80% of individuals larger than 30 shoots in the three species. M. densa is self-incompatible, and the fruit set obtained from cross pollination (42.7%) was higher than that obtained from natural pollination (18.2%), suggesting that this species could be pollinator limited. S. livida is autocompatible, not autogamous, and was not pollinator limited. Our results show that the coffee plantation had abundant orchid populations with log-normal size/age structures. Two of the target species, M. densa and S. livida, depend on pollinators to reproduce. It is clear that pollinators that allow orchids to set a high proportion of fruits persist in shade-coffee plantations. Coffee plantations may not replace the original conditions of a forest, but it is possible that these and other orchid species survive and reproduce in coffee plantations that provide appropriate microclimate conditions for the plants, including pollinators. Resumen:,En el centro de Veracruz, México, las plantaciones de café han reemplazado a extensas áreas de bosque nublado montano. Las plantaciones cafetaleras de sombra con altos niveles de diversidad estructural proporcionan refugio a biota dependiente de bosques (e. g., aves e insectos). En el dosel de agroecosistemas de café de sombra también se pueden encontrar orquídeas típicas de bosques naturales. Sin embargo, no se conoce si son relictos de la vegetación del bosque original o si las plantaciones mismas proporcionan los recursos necesarios para soportar a una población de orquídeas auto sostenida. Estudiamos la estructura de la población de orquídeas epifitas Jacquiniella teretifolia (Sw.) Britton & Willson, Scaphyglottis livida (Lindl.) Schltr y Maxillaria densa Lindl en una plantación de café de sombra (policultivo comercial) en el centro de Veracruz. También estudiamos la biología reproductiva, no descrita previamente, de las últimas dos especies. Nuestros resultados muestran que las tres especies de orquídea tuvieron densidades poblacionales altas (>800 plantas/ha). En nuestro sitio de estudio, entre 50% y 68% de las plantas de las especies estudiadas eran individuos jóvenes (menos de cinco rebrotes). En las tres especies hubo presencia de estructuras reproductivas en 80% de los individuos con más de 30 rebrotes. M. densa es auto incompatible, y el conjunto de frutos obtenido por polinización cruzada (42.7%) fue mayor que el obtenido por polinización natural (18.2%), lo que sugiere que esta especie puede estar limitada por polinizadores. S. livida es autocompatible no autogama, y no fue limitada por polinizadores. Nuestros resultados muestran que la plantación de café tenía poblaciones de orquídeas abundantes con estructuras tamaño/edad log normales. Dos de las especies, M. densa y S. livida, dependen de polinizadores para su reproducción. Es claro que los polinizadores que permiten una alta proporción de frutos a las orquídeas persisten en las plantaciones. Puede que las plantaciones de café no sustituyan las condiciones originales de un bosque, pero es posible que estas, y otras, especies de orquídeas sobrevivan y se reproduzcan en plantaciones de café que proporcionen condiciones microclimáticas adecuadas, incluyendo polinizadores, para las plantas. [source] A Review of Feral Cat Eradication on IslandsCONSERVATION BIOLOGY, Issue 2 2004MANUEL NOGALES efecto de depredación; erradicación; Felis catus; gato asilvestrado; islas Abstract:,Feral cats are directly responsible for a large percentage of global extinctions, particularly on islands. We reviewed feral cat eradication programs with the intent of providing information for future island conservation actions. Most insular cat introductions date from the nineteenth and twentieth centuries, whereas successful eradication programs have been carried out in the last 30 years, most in the last decade. Globally, feral cats have been removed from at least 48 islands: 16 in Baja California (Mexico), 10 in New Zealand, 5 in Australia, 4 in the Pacific Ocean, 4 in Seychelles, 3 in the sub-Antarctic, 3 in Macaronesia (Atlantic Ocean), 2 in Mauritius, and 1 in the Caribbean. The majority of these islands (75%; n= 36) are small (,5 km2). The largest successful eradication campaign took place on Marion Island (290 km2), but cats have been successfully removed from only 10 islands (21%) of ,10 km2. On Cousine Island (Seychelles) cat density reached 243 cats/km2, but on most islands densities did not exceed 79.2 cats/km2 (n= 22; 81%). The most common methods in successful eradication programs were trapping and hunting (often with dogs; 91% from a total of 43 islands). Frequently, these methods were used together. Other methods included poisoning (1080; monofluoracetate in fish baits; n= 13; 31%), secondary poisoning from poisoned rats (n= 4; 10%), and introduction of viral disease (feline panleucopaenia; n= 2; 5%). Impacts from cat predation and, more recently, the benefits of cat eradications have been increasingly documented. These impacts and benefits, combined with the continued success of eradication campaigns on larger islands, show the value and role of feral cat eradications in biodiversity conservation. However, new and more efficient techniques used in combination with current techniques will likely be needed for success on larger islands. Resumen:,Los gatos asilvestrados han sido responsables directos de un gran número de extinciones, particularmente en islas. En este estudio, se revisan los programas de erradicación de este felino con el fin de ofrecer información de utilidad en futuras acciones de conservación en islas. La mayor parte de las introducciones datan de los siglos diecinueve y veinte, mientras que las erradicaciones han sido realizadas básicamente durante los últimos 30 años, y sobre todo en la última década. Los gatos asilvestrados han sido erradicados de al menos 48 islas: 16 de ellas en Baja California (México), 10 en Nueva Zelanda, 5 en Australia, 4 en el Océano Pacífico, 4 en Seychelles, 3 en la Región Subantártica, 3 en Macaronesia (Océano Atlántico), 2 en Mauricio, y una en el Caribe. La mayoría de éstas (75%; n= 36) son de reducidas dimensiones (,5 km2), mientras que la más extensa es Marion Island (290 km2). En tan sólo 10 islas (21%) , 10 km2 se ha podido erradicar este depredador. En Cousine Island (Seychelles) la densidad de gatos alcanzó 243 individuos/km2; sin embargo, en la mayoría de las islas, las densidades no excedieron los 79,2 individuos/km2 (n= 22; 81%). Los métodos más comúnmente empleados fueron el trampeo y la caza, a menudo con perros (91% de un total de 43 islas). Con frecuencia dichas prácticas fueron empleadas conjuntamente. Otros métodos incluyeron venenos (1080, monofluoracetato de sodio en cebos de pescado: n= 13; 31%), envenenamiento secundario con ratas envenenadas (n= 4; 10%) y el virus de la leucemia felina (n= 2; 5%). La información sobre el efecto negativo de los gatos en islas y, más recientemente, el beneficio de su erradicación, se ha ido dando a conocer paulatinamente, poniendo de manifiesto su importancia en la conservación de la biodiversidad insular. No obstante, la combinación de técnicas nuevas y más eficientes junto con las habituales, será necesaria para el éxito de la erradicación de los gatos en islas de grandes dimensiones. [source] Mexico's Community-Managed Forests as a Global Model for Sustainable LandscapesCONSERVATION BIOLOGY, Issue 3 2003David Barton Bray On the other hand, conservationists have declared that the only way to stem the tide of deforestation is to place as many tracts as possible under strict protection. In this context, Mexico presents a national laboratory for studying the social and ecological benefits of delivering forests to local people. As a little-noticed result of the Mexican Revolution in the second decade of the twentieth century, well over half of the forests of Mexico were placed in community-held lands. In historic struggles that passed through several phases, most of these communities have now gained substantial control over the use of their forests. Because of the substantial degree of social capital in rural forms of organization in Mexico, this control of forest resources has led to an estimated 290,479 community forest enterprises ( CFEs ), through which communities are producing timber on their own lands. New studies are beginning to suggest that important gains in both social and economic justice, good forest management, and biodiversity protection are resulting from the actions of these CFEs. As more forests globally are being devolved to local communities, it is important to carry out more research on the Mexican model of community forest management for timber production. Resumen: Investigadores preocupados por el manejo sostenible de bosques en los trópicos han argumentado que el camino para una custodia mas efectiva de los recursos forestales es la transferencia de la responsabilidad a las comunidades locales que obtienen sustento de ellos. Por otro lado, conservacionistas han declarado que la única manera de detener la ola de deforestación es colocar bajo protección estricta tantas regiones como sea posible. En este contexto, México representa un laboratorio para el estudio de los beneficios sociales y ecológicos de entregar los bosques a los habitantes locales. Como un resultado poco conocido de la Revolución Mexicana, en la segunda década del siglo veinte, más de la mitad de los bosques de México se ubicaban en tierras que estaban en manos de las comunidades. Las comunidades forestales han atravesado por distintas etapas de conflicto, tras la cuáles han obtendio un control sustancial de los usos de sus bosques. Debido al nivel considerable de capital social en formas de organización rural en México, este control de los recursos forestales ha conducido a la integración de entre 290,479 empresas forestales comunitarias ( EFC ), en las que las comunidades están produciendo madera en sus propias tierras. Nuevos estudios están comenzando a sugerir que se están produciendo ganancias importantes en las acciones de estas EFC están generando beneficios importantes, tanto en lo que se refiere a justicia social como económica, la administración correcta de bosques y la protección de la biodiversidad. A medida en que se deleguen mayores extensiones de bosques a comunidades locales, es importante llevar a cabo más investigación sobre el modelo mexicano de manejo comunitario de bosques para la producción de forestal maderable. [source] The North American Industry Classification System and Its Implications for Accounting Research,CONTEMPORARY ACCOUNTING RESEARCH, Issue 4 2003Jayanthi Krishnan Abstract Industry classification is an important component of the methodological infrastructure of accounting research. Researchers have generally used the Standard Industrial Classification (SIC) system for assigning firms to industries. In 1999, the major statistical agencies of Canada, Mexico, and the United States began implementing the North American Industry Classification System (NAICS). The new scheme changes industry classification by introducing production as the basis for grouping firms, creating 358 new industries, extensively rearranging SIC categories, and establishing uniformity across all NAFTA nations. We examine the implications of the change for accounting research. We first assess NAICS's effectiveness in forming industry groups. Following Guenther and Rosman 1994, we use financial ratio variances to measure intra-industry homogeneity and find that NAICS offers some improvement over the SIC system in defining manufacturing, transportation, and service industries. We also evaluate whether NAICS might have an impact on empirical research by reproducing part of Lang and Lundholm's 1996 study of information-transfer and industry effects. Using SIC delineations, they focus on whether industry conditions or the level of competition is the main source of uncertainty resolved by earnings announcements. Across all levels of aggregation, we find inferences are similar using either SIC or NAICS. How-ever, we also observe that the regression coefficients in Lang and Lundholm's model show smaller intra-industry dispersion for NAICS, relative to SIC, definitions. Overall, the results suggest that NAICS definitions lead to more cohesive industries. Because of this, researchers may encounter some differences in using NAICS-industry definitions, rather than SIC, but these will depend on research design and industry composition of the sample. [source] CONSUMING CLASS: Multilevel Marketers in Neoliberal MexicoCULTURAL ANTHROPOLOGY, Issue 3 2008PETER S. CAHN ABSTRACT Since the 1980s, Mexican leaders have followed other Latin American countries in pursuing neoliberal economic policies designed to stimulate foreign investment, reduce public spending, and promote free trade. Recent studies of indigenous movements and popular protests challenge the idea that these market-based economic reforms enjoy a broad consensus and suggest that elites impose them by force. By turning the focus to middle-class Mexicans, I argue that some nonelite sectors of society avidly welcome the reign of the free market. Although they do not profit directly from unregulated capitalism, the middle class looks to neoliberalism to ensure access to the material markers of class status. The rising popularity of multilevel marketing companies in Mexico, which glorify consumption and celebrate the possibilities of entrepreneurship, demonstrates the appeal of neoliberalism to citizens fearful of diminished purchasing power. By tying consumption to globalized free markets, neoliberalism does not need coercion to win acceptance. [source] Mutant Ecologies: Radioactive Life in Post,Cold War New MexicoCULTURAL ANTHROPOLOGY, Issue 4 2004Joseph Masco A political ecology of the nuclear age developed through a theorization of "mutation" interrogates the contemporary terms of radioactive nature in New Mexico. As an analytic, the value of "mutation" is its emphasis on multigenerational effects, enabling an assessment of biosocial transformations as, alternatively, injury, improvement, or noise. Cold War radiation experiments, the post,Cold War transformation of nuclear production sites into "wildlife reserves," and the expanding role that biological beings play as "environmental sentinels" in New Mexico are all sites where concerns about "species" integrity may be articulated in relation to radioactive nature. [source] Working Under Contract for the Vegetable Agroindustry in Mexico: A Means of SurvivalCULTURE, AGRICULTURE, FOOD & ENVIRONMENT, Issue 3 2001Flavia Echánove Huacuja First page of article [source] Trends in Pediatric Melanoma Mortality in the United States, 1968 through 2004DERMATOLOGIC SURGERY, Issue 2 2008KEVAN G. LEWIS MD BACKGROUND AND OBJECTIVE Mortality from melanoma in children is a poorly understood and controversial problem in dermatology. There is paucity of research into this important public health dilemma. The purpose of this study was to characterize pediatric melanoma mortality in the United States and to evaluate trends over time. METHODS AND MATERIALS Deaths were derived from a database of more than 75 million records of the U.S. Center for National Health Statistics based on routine death certification. Information on age, race, gender, and geographic location was available for years 1968 through 2004. RESULTS During the 37-year period, there were 643 deaths attributed to melanoma in children under 20 years of age in the United States, an average of 18 per year. The overall age-adjusted mortality rate for melanoma in children was 2.25 deaths per year (per 10 million at-risk individuals). Mortality rates were strongly associated with age. In the oldest age group (age 15,19 years) the mortality rate was approximately an order of magnitude 8,18 times higher compared to younger age groups. Mortality among males was 25% higher than females. Mortality rates for white children were more than twice as high as black children. Overall mortality from melanoma in children declined steadily from 1968 to 2004. The highest mortality rates were observed in Idaho, Nevada, Arizona, and New Mexico. CONCLUSIONS Although mortality from melanoma among children in the United State is low, the magnitude of the public health burden from this preventable cause of death is substantial. In contrast to results of studies suggesting that the incidence of melanoma may be rising in children and adolescents, the data suggest that mortality in these groups may be falling. Additional study is warranted to further characterize and ultimately reduce mortality from childhood melanoma. [source] REPRODUCTIVE TOURISM IN ARGENTINA: CLINIC ACCREDITATION AND ITS IMPLICATIONS FOR CONSUMERS, HEALTH PROFESSIONALS AND POLICY MAKERSDEVELOPING WORLD BIOETHICS, Issue 2 2010ELISE SMITH ABSTRACT A subcategory of medical tourism, reproductive tourism has been the subject of much public and policy debate in recent years. Specific concerns include: the exploitation of individuals and communities, access to needed health care services, fair allocation of limited resources, and the quality and safety of services provided by private clinics. To date, the focus of attention has been on the thriving medical and reproductive tourism sectors in Asia and Eastern Europe; there has been much less consideration given to more recent ,players' in Latin America, notably fertility clinics in Chile, Brazil, Mexico and Argentina. In this paper, we examine the context-specific ethical and policy implications of private Argentinean fertility clinics that market reproductive services via the internet. Whether or not one agrees that reproductive services should be made available as consumer goods, the fact is that they are provided as such by private clinics around the world. We argue that basic national regulatory mechanisms are required in countries such as Argentina that are marketing fertility services to local and international publics. Specifically, regular oversight of all fertility clinics is essential to ensure that consumer information is accurate and that marketed services are safe and effective. It is in the best interests of consumers, health professionals and policy makers that the reproductive tourism industry adopts safe and responsible medical practices. [source] | ||||||||||||||||||||||||||||||||||||||||||||||