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Mexicali, Mexico

The Autonomous University of Baja California Sur is a Mexican public university based in the state of Baja California Sur.Its library holds over 42,000 volumes. Wikipedia.

Ramirez-Rodriguez M.,National Polytechnic Institute of Mexico | Ojeda-Ruiz M.T.,National Polytechnic Institute of Mexico | Ojeda-Ruiz M.T.,Autonomous University of Baja California Sur
Marine Policy | Year: 2012

To understand small-scale fisheries in Mexico, the spatial and temporal distribution of the landed catch of several species was analyzed, including abalone, clams, snails, octopus, squids, lobsters, shrimps, blue crabs, sharks, rays and finfish along the 349. km of the Gulf of Ulloa coast. Data reported by fishers from 1998 to 2009 on catch volume and value per group of species and per fishing locality, together with the number of landing events, were used to define fishing zones and the relative importance of each fishery. Finfish turned out the primary fishery in the region, but the other fisheries showed relevant spatial changes that should be considered when establishing management goals and fishing regulations according to resource availability, fleet efficiency, processing capacity, commercialization of fishing products and profit distribution. © 2011 Elsevier Ltd. Source

Angel Ojeda Ruiz de la Pena M.,Autonomous University of Baja California Sur | Ramirez Rodriguez M.,National Polytechnic Institute of Mexico
Ocean and Coastal Management | Year: 2014

In order to provide information to strengthen the implementation of management measures as part of the ecosystem, we analyzed the fleet operation dynamics of "Catarina" clam and shrimp, as well as the overlap of fishing seasons and zones at Magdalena-Almejas Bay region. Maps were created delimiting fishing zones, considering the lagoon complex physiographic features, fishing gear in use, depth and the spatial and temporal distribution of catches. The validated results by a study of local knowledge help us to understand how fleets operate during periods of interaction between these fisheries, the perceptions, preferences and tactics of producers to these events. It was found that economic units have permits to exploit multiple resources and must decide in the medium term which fishing gear to invest and in the short term which fishery and area to participate. The impacts of direct interactions are reduced by the users trading strategies, who to choose among more than an open season, use the abundance of the resource as the main criterion (65%), followed by the beachfront price paid for the resource (15%). The spatial interactions analyzed in thematic map of frequency of use showed congestion and distribution problems that tend to worsen over time so it is recommended to move from the management scheme of one fishery to multi fisheries within a region or ecosystem. © 2013 Elsevier Ltd. Source

Wurl J.,Autonomous University of Baja California Sur | Mendez-Rodriguez L.,National Polytechnic Institute of Mexico | Acosta-Vargas B.,National Polytechnic Institute of Mexico
Journal of Hydrology | Year: 2014

The San Antonio-El Triunfo mining district is located in a mountain region 60km southeast of La Paz, the capital of the Mexican state of Baja California Sur. Mining activities, focused on gold and silver extraction, which began in the second half of the 18th century; the main activity took place between 1878 and 1911. The minerals were treated through the cyanide method, burned, and smelted. In effect between 800,000 and 1milliontons of mine waste materials were scattered in an area of approximately 350-400km2. This area contains today several byproducts as a result from arsenopyrite oxidation, such as arsenolite (As2O3).The aim of this study was to analyze groundwater composition in order to define the actual concentrations of relevant parameters to detect ore mining contaminations, especially in respect to arsenic. In the autumn of 2010, 29 groundwater samples were obtained using flow-through bailer or down-hole pump methods, and a total of 37 variables were measured in each sample. Arsenic (dissolved) exceeded the values established by the World Health Organization (WHO, 2011) (0.01. mg/L) in 41% of the monitored sites. The maximum concentration of arsenic found in one observation well was 0.45. mg/L.Four water samples, which were characterized by elevated concentration of boron (max. conc. 9.5. mg/L), fluoride (max. conc. 3.25. mg/L) and alkaline pH values (>9), showed a composition typical for hydrothermal water. Because all four samples had arsenic concentration under 0.008. mg/L, we conclude that no significant impact of arsenic from hydrothermal fluids is found in the study area. © 2014 Elsevier B.V.. Source

Alonso-Hernando A.,University of Leon | Guevara-Franco J.A.,Autonomous University of Baja California Sur | Alonso-Calleja C.,University of Leon | Capita R.,University of Leon
Journal of Food Protection | Year: 2013

The influence of the temperature of the dipping solution on the antimicrobial effectiveness of several chemical poultry decontaminants was assessed. A total of 765 poultry legs were inoculated with gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, or Brochothrix thermosphacta) or gram-negative bacteria (Salmonella enterica serotype Enteritidis, Escherichia coli, Yersinia enterocolitica, or Pseudomonas fluorescens). Samples were dipped for 15 min in solutions (wt/vol) of trisodium phosphate (12%), acidified sodium chlorite (1,200 ppm), citric acid (2%), peroxyacids (220 ppm), chlorine dioxide (50 ppm), or tap water or were left untreated (control). The temperatures of the dipping solutions were 4, 20, or 50°C. Microbiological analyses and pH determinations were carried out after 0, 1, 3, and 5 days of storage at 4°C. In comparison with the control samples, all chemical solutions were effective for reducing microbial loads. The temperature of treatment affected the microbial reductions caused by all chemicals (P < 0.001). The lowest average bacterial reductions caused by trisodium phosphate, acidified sodium chlorite, citric acid, and peroxyacids were observed at 4°C, all sampling days and microbial groups being considered simultaneously. The highest and the lowest effectiveness for chlorine dioxide were observed at 4 and 50°C, respectively. These results may be of use to meat processors for selecting the best conditions for decontamination treatments and may help the European Regulatory Authorities make their decisions for authorization of poultry decontamination treatments. Copyright ©, International Association for Food Protection. Source

Romero O.E.,Instituto Andaluz Of Ciencias Of La Tierra Csic Ugr | Lopez-Fuerte F.O.,Autonomous University of Baja California Sur
Diatom Research | Year: 2013

Based on light and scanning electron microscopy observations, a detailed description of a new marine alveolate Cocconeis Ehrenberg, C. thalassiana sp. nov., is presented. This large Cocconeis was found in samples collected from a shallow marine coastal lagoon of the Mexican Caribbean, as an epiphyte on the marine seagrass Thalassia testudinum Banks ex König. Among alveolate Cocconeis, the presence of long alveoli for every stria opening into the frustule interior by two long internal apertures of the sternum valve (SV) is a unique character. Other typical frustule features are: bilayered, convex SV thicker than the concave raphe-sternum valve (RSV), the inner face of the SV with hyaline areas between the two apical rows of apertures, the monolayered RSV with a narrow submarginal hyaline area following the valve outline, and the girdle consisting of only two valvocopulae (one for each valve). © 2013 The International Society for Diatom Research. Source

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