DNA barcodes for Mexican Cactaceae, plants under pressure from wild collecting

DNA barcodes could be a useful tool for plant conservation. Of particular importance is the ability to identify unknown plant material, such as from customs seizures of illegally collected specimens. Mexican cacti are an example of a threatened group, under pressure because of wild collection for the xeriscaping trade and private collectors. Mexican cacti also provide a taxonomically and geographically coherent group with which to test DNA barcodes. Here, we sample the matK barcode for 528 species of Cactaceae including approximately 75% of Mexican species and test the utility of the matK region for species-level identification. We find that the matK DNA barcode can be used to identify uniquely 77% of species sampled, and 79-87% of species of particular conservation importance. However, this is far below the desired rate of 95% and there are significant issues for PCR amplification because of the variability of primer sites. Additionally, we test the nuclear ITS regions for the cactus subfamily Opuntioideae and for the genus Ariocarpus (subfamily Cactoideae). We observed higher rates of variation for ITS (86% unique for Opuntioideae sampled) but a much lower PCR success, encountering significant intra-individual polymorphism in Ariocarpus precluding the use of this marker in this taxon. We conclude that the matK region should provide useful information as a DNA barcode for Cactaceae if the problems with primers can be addressed, but matK alone is not sufficiently variable to achieve species-level identification. Additional complementary regions should be investigated as ITS is shown to be unsuitable

Operational active fire mapping and burnt area identification applicable to Mexican Nature Protection Areas using MODIS and NOAA-AVHRR direct readout data

Since 1999, the National Commission for the Knowledge and Use of the Biodiversity (CONABIO) in Mexico has been developing and managing the “Operational program for the detection of hot-spots using remote sensing techniques”. This program uses images from the MODerate resolution Imaging Spectroradiometer (MODIS) onboard the Terra and Aqua satellites and from the Advanced Very High Resolution Radiometer of the National Oceanic and Atmospheric Administration (NOAA-AVHRR), which are operationally received through the Direct Readout station (DR) at CONABIO. This allows the near-real time monitoring of fire events in Mexico and Central America. In addition to the detection of active fires, the location of hot spots are classified with respect to vegetation types, accessibility, and risk to Nature Protection Areas (NPA). Besides the fast detection of fires, further analysis is necessary due to the considerable effects of forest fires on biodiversity and human life. This fire impact assessment is crucial to support the needs of resource managers and policy makers for adequate fire recovery and restoration actions. CONABIO attempts to meet these requirements, providing post-fire assessment products as part of the management system in particular for satellite-based burnt area mapping. This paper provides an overview of the main components of the operational system and will present an outlook to future activities and system improvements, especially the development of a burnt area product. A special focus will also be placed on the fire occurrence within NPAs of Mexico

Study of the lactation curve in dairy cattle on farms in Central Mexico

Accurate knowledge of lactation curves has an important relevance to management and research of dairy production systems. A number of equations have been proposed to describe the lactation curve, the most widely applied being the gamma equation. The objective of this work was to compare and evaluate candidate functions for their predictive ability in describing lactation curves from central Mexican dairy cows reared under 2 contrasting management systems. Five equations were considered: Gaines ( exponential decay), Wood ( gamma equation), Rook ( Michaelis-Menten x exponential), and 2 more mechanistic ones (Dijkstra and Pollott). A database consisting of 701 and 1283 records of cows in small-scale and intensive systems, respectively, was used in the analysis. Before analysis, the database was divided into 6 groups representing first, second, and third and higher parity cows in both systems. In all cases except second and above parity cows in small-scale systems, all models improved on the Gaines equation. The Wood equation explained much of the variation, but its parameters do not have direct biological interpretation. Although the Rook equation fitted the data well, some of the parameter estimates were not significant. The Dijkstra equation consistently gave better predictions, and its parameters were usually statistically significant and lend themselves to physiological interpretation. As such, the differences between systems and parity could be explained due to variations in theoretical initial milk production at parturition, specific rates of secretory cell proliferation and death, and rate of decay, all of which are parameters in the model. The Pollott equation, although containing the most biology, was found to be over-parameterized and resulted in nonsignificant parameter estimates. For central Mexican dairy cows, the Dijkstra equation was the best option to use in describing the lactation curve.

Modeling small-scale dairy farms in central Mexico using multi-criteria programming

Milk supply from Mexican dairy farms does not meet demand and small-scale farms can contribute toward closing the gap. Two multi-criteria programming techniques, goal programming and compromise programming, were used in a study of small-scale dairy farms in central Mexico. To build the goal and compromise programming models, 4 ordinary linear programming models were also developed, which had objective functions to maximize metabolizable energy for milk production, to maximize margin of income over feed costs, to maximize metabolizable protein for milk production, and to minimize purchased feedstuffs. Neither multicriteria approach was significantly better than the other; however, by applying both models it was possible to perform a more comprehensive analysis of these small-scale dairy systems. The multi-criteria programming models affirm findings from previous work and suggest that a forage strategy based on alfalfa, rye-grass, and corn silage would meet nutrient requirements of the herd. Both models suggested that there is an economic advantage in rescheduling the calving season to the second and third calendar quarters to better synchronize higher demand for nutrients with the period of high forage availability.

Forage production and nutrient availability in small-scale dairy systems in central Mexico using linear programming and partial budgeting

Small-scale dairy systems play an important role in the Mexican dairy sector and farm planning activities related to resource allocation have a significant impact on the profitability of such enterprises. Linear programming is a technique widely used for planning and ration formulation, and partial budgeting is a technique for assessing the impact of changes on the profitability of an enterprise. This study used both methods to optimise land use for forage production and nutrient availability, and to evaluate the economic impact of such changes in small-scale Mexican dairy systems. The model showed satisfactory performance when optimal solutions were compared with the traditional strategy. The strategy using fresh ryegrass, maize silage and oat hay, and the strategy using a combination of alfalfa hay, maize silage, fresh ryegrass and oat hay appeared attractive options for providing a better nutrient supply and maintaining a higher stocking rate throughout the year than the traditional strategy.

Typification of four North American club-chollas: the names of four Engelmannian species from Mexico and Southwestern United States

The names Opuntia bulbispina, O. clavata, O. emoryi and O. grahamii, originally proposed by George Engelmann between 1848 and 1856, are reviewed and typified after new findings of previously unknown voucher specimens. Original materials collected by some of the collaborators employed by Engelmann during the Mexican Boundary Survey were discovered in a loan from the Torrey Herbarium at the New York Botanical Garden (NY). Many of the materials include fragments of stems and fruits, and others include only sectioned flowers and some seeds. Particularly good descriptions of the species here concerned were published in Engelmann’s “Synopsis of the Cactaceae” in 1857, and exceptional illustrations were produced by Paulus Roetter and printed in “Cactaceae of the Boundary” in 1859. The problems surrounding some previous typifications of these names range from typification of joint lectotypes to illegitimate typifications of illustrations when original material was known to exist. The materials selected for typification were collected by the Mexican Boundary Survey and are lodged at the herbaria of the Missouri Botanical Garden (MO) and the New York Botanical Garden (NY); some are illustrations published by Engelmann.

Adoption of certified organic production: evidence from Mexico

Adoption of organic production and subsequent entry into the organic market is examined using Mexican avocado producers as a case study. Probit analysis of a sample of 183 small-scale (<15ha) producers from Michoacán suggests that adoption is positively influenced by management and economic factors (e.g. production costs per hectare and making inputs), but also by social factors (e.g. membership of a producers’ association). Experience in agriculture has a significant but negative effect. Effective policy design must be therefore be aware of both the economic and social complexities surrounding adoption decisions.

Going global: the Brazilian scripted film

This article departs from the assumption that a certain section of world cinema, usually defined as ‘independent’, has been evolving on the basis of good scripts. Between the late 1980s and early 90s, there has been a boom of new cinemas in the world, such as the new Iranian, Taiwanese, Japanese, Mexican, Argentine and Brazilian cinemas. A significant part of this production shows a renewed interest in local and national peculiarities of their respective countries, going against the grain of globalisation and its typical cultural dilution. Most of these films are also engaged in reassessing narrative cinema, as a kind of reaction against the deconstructive work carried out by postmodern cinema of the 1980s.Recent new cinemas are supported by a combination of local and international resources, derived from public and private sponsors at home, and funding agencies, festivals and TV channels abroad. In most cases funds are granted after the film script has been analysed and approved by commissions of experts. The New Brazilian Cinema, or cinema da retomada as it is locally called, has been enormously affected by this scheme, which has even caused a ‘script boom’ in Brazil in the past decade. The chapter examins the results of this process.

Generation and analysis of the 2005 land cover map for Mexico using 250m MODIS data

Land cover plays a key role in global to regional monitoring and modeling because it affects and is being affected by climate change and thus became one of the essential variables for climate change studies. National and international organizations require timely and accurate land cover information for reporting and management actions. The North American Land Change Monitoring System (NALCMS) is an international cooperation of organizations and entities of Canada, the United States, and Mexico to map land cover change of North America's changing environment. This paper presents the methodology to derive the land cover map of Mexico for the year 2005 which was integrated in the NALCMS continental map. Based on a time series of 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) data and an extensive sample data base the complexity of the Mexican landscape required a specific approach to reflect land cover heterogeneity. To estimate the proportion of each land cover class for every pixel several decision tree classifications were combined to obtain class membership maps which were finally converted to a discrete map accompanied by a confidence estimate. The map yielded an overall accuracy of 82.5% (Kappa of 0.79) for pixels with at least 50% map confidence (71.3% of the data). An additional assessment with 780 randomly stratified samples and primary and alternative calls in the reference data to account for ambiguity indicated 83.4% overall accuracy (Kappa of 0.80). A high agreement of 83.6% for all pixels and 92.6% for pixels with a map confidence of more than 50% was found for the comparison between the land cover maps of 2005 and 2006. Further wall-to-wall comparisons to related land cover maps resulted in 56.6% agreement with the MODIS land cover product and a congruence of 49.5 with Globcover.

A Linguistic Analysis of Spanglish: Relating Language to Identity.

According to the 2000 census, 35.3 million Hispanics live in the United States. This number comprises 12.5% of the overall population rendering the Latino community the largest minority in the United States. The Mexican community is not only the largest Hispanic group but also the fastest growing: from 1990 to 2000, the Mexican population grew 52.9% increasing from 13.5 million to 20.6 million (U.S. Department of Commerce News, 2001). The influx of Mexican immigrants coupled with the expansion of their community within the United States has created an unparalleled situation of language contact. Language is synonymous with identity (cf. Granger, 2004, and works cited within). To the extent that this is true, Spanish is synonymous with being Mexican and by extension, Chicano. With the advent of amnesty programs such as Immigration Reform and Control Act (IRCA), which naturalized millions of Mexican migrants, what was once a temporal migratory population has become increasingly permanent (Durand et al., 1999). In an effort to conserve Mexican traditions and identity, the struggle to preserve the mother tongue while at the same time acculturate to mainstream Americana has resulted in a variant of Spanglish that has received little attention. This paper will examine the variant of Spanglish seen in the greater Los Angeles area and liken it to the bi-national identity under which these Mexican Americans thrive.

Recovering the counterfactual wage distribution with selective return migration

This paper recovers the distribution of wages for Mexican-born workers living in the U.S. if no return migration of Mexican-born workers occurred. Because migrants self-select in the decision to return, the overarching problem addressed by this study is the use of an estimator that also accounts for selection on unobservables. I find that Mexican returnees are middle- to high-wage earners at all levels of educational attainment. Taking into account self-selection in return migration, wages would be approximately 7.7% higher at the median and 4.5% higher at the mean. Owing to positive self-selection, the immigrant-native wage gap would, therefore, partially close if there was no return migration.

Echoes of 1992: the NAFTA negotiations and North America now

Two decades ago, Canada, Mexico, and the United States created a continental economy. The road to integration from the signing of the North American Free Trade Agreement has not been a smooth one. Along the way, Mexico lived through a currency crisis, a democratic transition, and the rising challenge of Asian manufacturing. Canada stayed united despite surging Quebecois nationalism during the 1990s; since then, it has seen dramatic economic changes with the explosion of hydrocarbon production and a much stronger currency. The United States saw a stock-market bust, the shock of 9/11, and the near-collapse of its financial system. All of these events have transformed the relationships that emerged after NAFTA entered into force in 1994. Given the tremendous changes, one might be skeptical that the circumstances and details of the negotiation and ratification of NAFTA hold lessons for the future of North America. However, the road to NAFTA had its own difficulties, and many of the issues involved in the negotiations underpin today's challenges. NAFTA was conceived at a time of profound change in the international system. When Mexican leaders surveyed the world two decades ago, they saw emerging regional groupings in Europe, Asia, and South America. Faced with a lack of interest or compatibility, they instead doubled down on North America. How did Mexican leaders reconsider their national interests and redefine Mexico's role in the world in light of those transformations? Unpublished Mexican documents from SECOFI, the secretariate most involved in negotiating NAFTA, help illustrate Mexican thinking about its interests and role at that time. Combining those insights with analysis of newly available evidence from U.S. presidential archives, this paper sheds light on the negotiations that concluded two decades ago.