WorldWideScience

Sample records for region baja california

  1. Baja California: literatura y frontera

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    Gabriel Trujillo Muñoz

    2014-06-01

    Baja California is a region that not only has migration problems and criminal violence because of the war of drugs or is a space of border conflicts in close neighborhood with the United States of America. Baja California is too a geographic space of culture and art, of creative writing and struggle to narrate the things and persons that here live, a plain sight, like their house, like their home, like a center of creation. This text give a cultural context of the border literature in the north of Mexico like a phenomenon in notice because his own merits, books and writers.

  2. Occurrence of Batrachochytrium dendrobatidis in anurans of the Mediterranean region of Baja California, México

    Science.gov (United States)

    Peralta-Garcia, Anny; Adams, Andrea J.; Briggs, Cheryl J.; Galina-Tessaro, Patricia; Valdez-Villavicencio, Jorge H.; Hollingsworth, Bradford; Shaffer, H. Bradley; Fisher, Robert N.

    2018-01-01

     Chytridiomycosis is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) and is regarded as one of the most significant threats to global amphibian populations. In México, Bd was first reported in 2003 and has now been documented in 13 states. We visited 33 localities and swabbed 199 wild-caught anurans from 7 species (5 native, 2 exotic) across the Mediterranean region of the state of Baja California. Using quantitative PCR, Bd was detected in 94 individuals (47.2% of samples) at 25 of the 33 survey localities for 5 native and 1 exotic frog species. The exotic Xenopus laevis was the only species that tested completely negative for Bd. We found that remoteness, distance to agricultural land, and elevation were the best predictors of Bd presence. These are the first Bd-positive results for the state of Baja California and its presence should be regarded as an additional conservation threat to the region’s native frog species. 

  3. Regional stratigraphy, sedimentology, and tectonic significance of Oligocene-Miocene sedimentary and volcanic rocks, northern Baja California, Mexico

    Science.gov (United States)

    Dorsey, Rebecca J.; Burns, Beverly

    1994-01-01

    Upper Oligocene (?) to middle Miocene sedimentary and volcanic rocks in northern Baja California were deposited along the western margin of North America during subduction of the Guadalupe plate and southward migration of the Rivera Triple Junction. Regional mapping and compilation of stratigraphic data reveal a sequence of three regionally traceable stratigraphic units. (1) Oligocene (?) to lower Miocene Mesa Formation: basal quartz-rich fluvial sandstone, grus, conglomerate, and accessory facies, whose detrital compositions reflect the composition of local pre-Tertiary basement rock. (2) Lower to middle Miocene Comondú Formation: laterally variable sequence of volcaniclastic conglomerate, breccia, sandstone, tuff and minor volcanic flow units. (3) Widespread mesa-capping rhyolite tuff, typically welded and crystal-rich, probably upper Miocene in age. The Mesa Formation overlies a highly irregular and deeply dissected erosional surface developed on pre-Tertiary basement rock. The shift from pre-Mesa erosion to widespread (though localized) deposition and valley-filling records the final phase of late Cretaceous to middle Tertiary regional subsidence and eastward transgression that resulted from slow cooling and thermal contraction of Cretaceous arc crust during a temporal gap in magmatic activity along the western Cordilleran margin. Nonmarine sediments of the Mesa Formation were deposited in small, steep-walled paleovalleys and basins that gradually filled and evolved to form through-going, low-energy ephemeral stream systems. The gradational upward transition from the Mesa to Comondú Formation records the early to middle Miocene onset of subduction-related arc magmatism in eastern Baja California and related westward progradation of alluvial volcaniclastic aprons shed from high-standing eruptive volcanic centers. Pre-existing streams were choked with the new influx of volcanic detritus, causing the onset of rapid sediment deposition by stream flows and dilute

  4. Phytoplankton oceanographic characterization during El Niño 2004 event in the Northwest region of Baja California, Mexico

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    Miranda-Alvarez, A. C.

    2016-09-01

    Full Text Available An oceanographic cruise in front of the Coast of Baja California was carried from the 9th to the 29th day of July in 2004, in 91 stations at 10 m depth. The aim of this study was to identify the variability of phytoplankton and its oceanographic characterization in the coast-ocean region during an anomalous year with El Niño characteristics. Results showed a taxonomic composition of 21 phytoplankton genera in an interval size called nano-microphytoplankton: Gymnodinium, Scrippsiella, Ceratium, Coscinodiscus, Oxytoxum, Gyrodinium, Protoperidinium, Nitzschia, Gonyaulax. On the other hand, spatial distribution of light absorption coefficient for phytoplankton (aph440 and chlorophyll-a (Chl-a concentration showed high values in front of the San Quintin coast and south of Punta Eugenia, detecting a clear decrease towards the oceanic zone. In regard to the taxonomic composition of phytoplankton, a dominance of dinoflagellates in contrast to diatoms was observed, results coinciding with the basic characteristics of phytoplankton ecology during an El Niño event.

  5. Louse flies on birds of Baja California

    OpenAIRE

    Tella, José Luis; Rodríguez-Estrella, Ricardo; Blanco, Guillermo

    2000-01-01

    Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (México). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

  6. Oligocene cetaceans from Baja California Sur, Mexico

    OpenAIRE

    Hernández Cisneros, Atzcalli Ehécatl; González Barba, Gerardo; Fordyce, Robert Ewan

    2017-01-01

    Abstract Baja California Sur has an important Cenozoic marine fossil record which includes diverse but poorly known Oligocene cetaceans from Mexico. Here we review the cetacean fossil record including new observations from materials that elucidate the evolution of the Neoceti in the Pacific basin. Fossils were collected from outcrops of the El Cien Formation (Oligocene-Early Miocene) and from San Gregorio Formation (Late Oligocene). The specimens belong to the paleontological collection of Mu...

  7. Marital arrangements in Baja California and its young adults

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    Norma Ojeda

    2014-11-01

    Full Text Available Uniones libres or consensual union formation has increased in Mexico and this is not an exception in its Northern region. Information from the Mexican Population and Household Census of 2010 and the Survey on Reproductive Health of Adolescents in Baja California, 2006 show that unión libre as an preferential type of conjugal arrangement is more clearly manifested among the Baja California’s youth of both sexes in general and particularly among those residing in Tijuana and Rosarito. Also, union libre formation among the Baja California’s youth is extensively associated with childbearing what seems to indicate continuity in its traditional role in the Mexican family formation process, but this is happening in higher proportions among the young adults of the new generations.

  8. Climate change and the northern elephant seal (Mirounga angustirostris population in Baja California, Mexico.

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    María C García-Aguilar

    Full Text Available The Earth's climate is warming, especially in the mid- and high latitudes of the Northern Hemisphere. The northern elephant seal (Mirounga angustirostris breeds and haul-outs on islands and the mainland of Baja California, Mexico, and California, U.S.A. At the beginning of the 21st century, numbers of elephant seals in California are increasing, but the status of Baja California populations is unknown, and some data suggest they may be decreasing. We hypothesize that the elephant seal population of Baja California is experiencing a decline because the animals are not migrating as far south due to warming sea and air temperatures. Here we assessed population trends of the Baja California population, and climate change in the region. The numbers of northern elephant seals in Baja California colonies have been decreasing since the 1990s, and both the surface waters off Baja California and the local air temperatures have warmed during the last three decades. We propose that declining population sizes may be attributable to decreased migration towards the southern portions of the range in response to the observed temperature increases. Further research is needed to confirm our hypothesis; however, if true, it would imply that elephant seal colonies of Baja California and California are not demographically isolated which would pose challenges to environmental and management policies between Mexico and the United States.

  9. Media and nationalism in Baja California during World War II

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    Víctor M. Gruel Sández

    2013-01-01

    Full Text Available The purpose of this work is to explain some journalistic representations of the Northern Territory of Baja California. The body of documents that pertain this article, will document different versions of the past of the peninsula, from the nature of political discourse. Bajacalifornians will appear represented by journalists, struggling to eliminate an image of an isolated, uninhabited place filled with U.S. citizens. The editorial portrayal of the Tijuana, Mexicali and Mexico City press will be analyzed in context with the regional, national and international conflicts. Public opinion was a ground where the people of Baja California negotiated the nationalism, as the rest of the world collapsed with World War ii.

  10. Learning in Baja California micro-enterprises

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    Michelle Texis Flores

    2011-01-01

    Full Text Available Mexico’s business structure has been characterized by the presence of microenterprises, particularly those averaging two workers, representing 65% of establishments in 2008 and 18% of employment. This makes them important for equity and welfare improvement of their members. This paper analyzes the performance of a group of 227 microenterprises in the state of Baja California, by the use of a practical application of the concept of learning curve arranged to incorporate returns to scale. The results indicate that in 48% of cases there is evidence of learning processes and 58% exhibited increasing returns to scale. This allows evaluating the development potential of these microenterprises and the design and implementation of proactive programs that encourage their learning and consolidation in the market.

  11. Tijuana, Baja California, 1999-2005

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    David F. Fuentes Romero

    2008-01-01

    Full Text Available En este artículo se analiza el perfil de las muertes violentas en las mujeres de Tijuana, Baja California. Los datos provienen de fuentes forense, hemerográfica y del análisis derivado de los expedientes de homicidios dolosos. Se encontró que el rango de edad con mayor frecuencia en los homicidios de mujeres se da entre los 20 y los 34 años (42 por ciento. Sin embargo, en las mujeres el riesgo de morir víctima de un asesinato es más alto en menores de 15 años (20 por ciento. Las formas y medios de mayor frecuencia para asesinar a las mujeres son: heridas por lesiones y golpes (42.3 por ciento, disparo con arma de fuego (28 por ciento, asfixia mecánica y herida por arma blanca (28.8 por ciento.

  12. Whole genome sequencing of Mycobacterium bovis to obtain molecular fingerprints in human and cattle isolates from Baja California, Mexico

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    Sarai Estrella Sandoval-Azuara

    2017-10-01

    Conclusions: All isolates from humans had spoligotype patterns that matched those observed in the cattle isolates, and all human isolates shared common ancestors with cattle in Baja California based on SNP analysis. This suggests that most human tuberculosis caused by M. bovis in Baja California is derived from M. bovis circulating in Baja California cattle. These results reinforce the importance of bovine tuberculosis surveillance and control in this region.

  13. Financial viability of the Sonora-Baja California interconnection line

    International Nuclear Information System (INIS)

    Alonso, G.; Ortega, G.

    2017-09-01

    In the Development Program of the National Electricity Sector 2015-2029, an electric interconnection line between Sonora and Baja California (Mexico) is proposed, this study analyzes the financial viability of this interconnection line based on the maximum hourly and seasonal energy demand between both regions and proposes alternatives for the supply of electric power that supports the economic convenience of this interconnection line. The results show that additional capacity is required in Sonora to cover the maximum demands of both regions since in the current condition of the National Electric System the interconnection line is not justified. (Author)

  14. Seismicity, focal mechanisms, and stress distribution in the Tres Virgenes volcanic and geothermal region, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Victor; Munguia, Luis [Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (Mexico)

    2006-01-15

    In October 1993 we carried out a seismic monitoring in the Tres Virgenes volcanic region in order to record the background seismicity associated with the volcanic structures, the geothermal field and the tectonic features of the area. Hypocenters for 257 microearthquakes were located in the volcanic edifices and along the northwest right-lateral, strike-slip La Virgen fault. Focal depths range from close to the Earth surface to about 8 km. Shallow depths occur mainly in the volcanic edifices. Deeper seismic events occurred outside the volcanic area. The duration magnitudes of the located microearthquakes range between 1 and 3. The Vp/Vs ratio and the low-Q values estimated suggest heterogeneous material properties in the volcanic structures mainly toward the El Azufre fault and the El Aguajito Caldera, where hydrothermal activity has been reported. The P- and T-axes of focal mechanisms for 90 microearthquakes suggest that the region is under N-S compression and E-W extension, in agreement with the regional tectonic stress field of the NW-SE right-lateral strike-slip transform fault system of the Gulf of California. [Spanish] En octubre de 1993 se llevo a cabo un monitoreo sismico en la region volcanica Las Tres Virgenes con el proposito de registrar la actividad sismica asociada a las estructuras volcanicas, al campo geotermico y a la tectonica local. Se localizaron 257 microsismos con hipocentros en los edificios volcanicos y a lo largo de la falla de rumbo, lateral derecha conocida como falla La Virgen. La profundidad focal de los sismos varia desde los muy cercanos a la superficie de la Tierra hasta los 8 km. Las profundidades someras ocurren principalmente en los edificios volcanicos. Los sismos mas profundos ocurren fuera del area volcanica. La magnitud de duracion de los microsismos localizados varia entre 1 y 3. La razon Vp/Vs y los valores bajos de Q que se estimaron en la zona sugieren un material con propiedades heterogeneas bajo las estructuras

  15. Cloud Feedback Key to Marine Heatwave off Baja California

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    Myers, Timothy A.; Mechoso, Carlos R.; Cesana, Gregory V.; DeFlorio, Michael J.; Waliser, Duane E.

    2018-05-01

    Between 2013 and 2015, the northeast Pacific Ocean experienced the warmest surface temperature anomalies in the modern observational record. This "marine heatwave" marked a shift of Pacific decadal variability to its warm phase and was linked to significant impacts on marine species as well as exceptionally arid conditions in western North America. Here we show that the subtropical signature of this warming, off Baja California, was associated with a record deficit in the spatial coverage of co-located marine boundary layer clouds. This deficit coincided with a large increase in downwelling solar radiation that dominated the anomalous energy budget of the upper ocean, resulting in record-breaking warm sea surface temperature anomalies. Our observation-based analysis suggests that a positive cloud-surface temperature feedback was key to the extreme intensity of the heatwave. The results demonstrate the extent to which boundary layer clouds can contribute to regional variations in climate.

  16. Terrestrial Birds and Conservation Priorities in Baja California Peninsula

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    Ricardo Rodriguez-Estrella

    2005-01-01

    The Baja California peninsula has been categorized as an Endemic Bird Area of the world and it is an important wintering area for a number of aquatic, wading and migratory landbird species. It is an important area for conservation of bird diversity in northwestern México. In spite of this importance, only few, scattered studies have been done on the ecology...

  17. A Weather Analysis and Forecasting System for Baja California, Mexico

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    Farfan, L. M.

    2006-05-01

    The weather of the Baja California Peninsula, part of northwestern Mexico, is mild and dry most of the year. However, during the summer, humid air masses associated with tropical cyclones move northward in the eastern Pacific Ocean. Added features that create a unique meteorological situation include mountain ranges along the spine of the peninsula, warm water in the Gulf of California, and the cold California Current in the Pacific. These features interact with the environmental flow to induce conditions that play a role in the occurrence of localized, convective systems during the approach of tropical cyclones. Most of these events occur late in the summer, generating heavy precipitation, strong winds, lightning, and are associated with significant property damage to the local populations. Our goal is to provide information on the characteristics of these weather systems by performing an analysis of observations derived from a regional network. This includes imagery from radar and geostationary satellite, and data from surface stations. A set of real-time products are generated in our research center and are made available to a broad audience (researchers, students, and business employees) by using an internet site. Graphical products are updated anywhere from one to 24 hours and includes predictions from numerical models. Forecasts are derived from an operational model (GFS) and locally generated simulations based on a mesoscale model (MM5). Our analysis and forecasting system has been in operation since the summer of 2005 and was used as a reference for a set of discussions during the development of eastern Pacific tropical cyclones. This basin had 15 named storms and none of them made landfall on the west coast of Mexico; however, four systems were within 800 km from the area of interest, resulting in some convective activity. During the whole season, a group of 30 users from our institution, government offices, and local businesses received daily information

  18. Envejecimiento y migración en Baja California

    OpenAIRE

    Ybáñez Zepeda, Elmyra; Alarcón, Rafael

    2007-01-01

    La población mayor de 60 años aumentará en números absolutos y relativos con una rapidez inusitada en México. Con base en datos del Censo general de población y vivienda 2000, de la Encuesta sobre migración en la frontera norte de México (Emif) y del Consejo Nacional de Población (Conapo), este artículo tiene dos objetivos principales: analizar cómo se ha dado el proceso de envejecimiento en los municipios de Tijuana y Mexicali, ubicados en Baja California, un estado caracterizado por la baja...

  19. Marine Spatial Planning in a Transboundary Context: Linking Baja California with California's Network of Marine Protected Areas

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    Nur Arafeh-Dalmau

    2017-05-01

    Full Text Available It is acknowledged that an effective path to globally protect marine ecosystems is through the establishment of eco-regional scale networks of MPAs spanning across national frontiers. In this work we aimed to plan for regionally feasible networks of MPAs that can be ecologically linked with an existing one in a transboundary context. We illustrate our exercise in the Ensenadian eco-region, a shared marine ecosystem between the south of California, United States of America (USA, and the north of Baja California, Mexico; where conservation actions differ across the border. In the USA, California recently established a network of MPAs through the Marine Life Protection Act (MLPA, while in Mexico: Baja California lacks a network of MPAs or a marine spatial planning effort to establish it. We generated four different scenarios with Marxan by integrating different ecological, social, and management considerations (habitat representation, opportunity costs, habitat condition, and enforcement costs. To do so, we characterized and collected biophysical and socio-economic information for Baja California and developed novel approaches to quantify and incorporate some of these considerations. We were able to design feasible networks of MPAs in Baja California that are ecologically linked with California's network (met between 78.5 and 84.4% of the MLPA guidelines and that would represent a low cost for fishers and aquaculture investors. We found that when multiple considerations are integrated more priority areas for conservation emerge. For our region, human distribution presents a strong gradient from north to south and resulted to be an important factor for the spatial arrangement of the priority areas. This work shows how, despite the constraints of a data-poor area, the available conservation principles, mapping, and planning tools can still be used to generate spatial conservation plans in a transboundary context.

  20. Captura de atún aleta azul en Baja California, México: ¿pesquería regional o maquiladora marina?

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    Raúl Jesús del Moral-Simanek

    2009-01-01

    Full Text Available El atún aleta azul, capturado por la flota mexicana en las costas de la península de Baja California, se destinaba al enlatado local, para ofrecer a los consumidores nacionales un producto barato y con valor nutritivo alto. Sin embargo, esto cambió en la última década con la llegada de inversionistas, sobre todo japoneses. Ahora el atún se captura, engorda y exporta a los mercados japonés y estadounidense, que pagan un precio elevado, para satisfacer su demanda de sashimi. Esto tiene repercusiones positivas en el orden social y económico en México y Japón; determinadas a partir del trabajo de campo directo e indirecto realizado en el marco de esta investigación. Además, se identificaron algunas similitudes entre el comportamiento de las empresas estudiadas y la industria maquiladora de exportación, lo que abrió un debate sobre el tema.

  1. Componentes de cambio y economía regional: El sector manufacturero en el estado de Baja California y en el municipio de Mexicali (1985-1988

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    Ma. Dolores Sánchez Soler

    1992-01-01

    Full Text Available Este trabajo se realizó con dos propósitos: el primero es comparar los cambios manifestados en la estructura del empleo manufacturero durante el período de 1985-1988, en el municipio de Mexicali, en relación con el estado de Baja California y el país en su conjunto; para ello se hace uso de la técnica de cambio y participación (shift & share utilizando la información de los censos económicos: El segundo, relacionado con el anterior, se refiere a la aplicación de las tres versiones de dicha técnica a fin de determinar cuál de éstas presenta mayores elementos para la descripción de los cambios observados. El trabajo muestra que la entidad presenta ventajas de localización en las actividades de manufactura de productos metálicos, maquinaria y equipos e instrumentos quirúrgicos y de precisión; mientras que en Mexicali se registran ventajas para las actividades de papel y productos de papel y productos minerales no metálicos, aun cuando no se reporta especialización.Finalmente, se concluye que el modelo síntesis, presentado por Bishop y Simpson, es el que aporta mayores elementos para la descripción.

  2. Financial viability of the Sonora-Baja California interconnection line; Viabilidad financiera de la linea de interconexion Sonora-Baja California

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, G. [ININ, Carretera Mexico-Touca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Ortega, G., E-mail: gustavo.alonso@inin.gob.mx [Comision Federal de Electricidad, Rio Rodano No. 14, Col. Cuauhtemoc, 06500 Ciudad de Mexico (Mexico)

    2017-09-15

    In the Development Program of the National Electricity Sector 2015-2029, an electric interconnection line between Sonora and Baja California (Mexico) is proposed, this study analyzes the financial viability of this interconnection line based on the maximum hourly and seasonal energy demand between both regions and proposes alternatives for the supply of electric power that supports the economic convenience of this interconnection line. The results show that additional capacity is required in Sonora to cover the maximum demands of both regions since in the current condition of the National Electric System the interconnection line is not justified. (Author)

  3. The physicochemical characterization of cave paintings of Baja California

    International Nuclear Information System (INIS)

    Valdez, B.; Cobo, J.; Schorr, M.; Cota, L.; Oviedo, F.

    2006-01-01

    The Palaeolithic paintings of Baja California constitute an important contribution to the national, historic and cultural patrimony of Mexico. The aim of this investigation was to determine the physicochemical characteristics, the microstructure and texture of these polychrome paintings, painted on rocks encountered in the mountainous, desert/arid zones of Baja California and Baja California South. The first stage of this work was devoted to the examination and recording of the cave paintings of 'El Vallecito', a narrow fluvial valley displaying large granitic rocks emerging from the sandy soil. Tiny painting samples were collected and analyzed by SEM, EDS and FTIR techniques. The painters used four main colours: red, black, yellow and white. The paint raw materials are mineral pigments: white (kaolin, calcite, and gypsum), red (hematite), yellow (ochre, limonite), black (charcoal from burnt wood or calcined bones) and water as a diluent and/or a binder, all encountered in the painters habitat. The minerals were collected, ground and sometimes heated to change their tone. By mixing with water, a spreadable paste or a thick slurry was produced, which was applied with the fingers for lines or a piece of animal skin for figures, respectively. The 100% solids, dry paint converts into a dense, hard layer, incrusted into the grainy, rough, hollow granite rock surface. This paint might be called s tone on stone , explaining its permanence for centuries enduring heat, wind and weather. A simulation of the painting technique was done at the Materials and Corrosion Laboratory, UABC by collecting mineral pigments, preparing the paint as a paste or slurry and applying it on a granitic rock. Knowing the paint composition, production and application techniques will be useful in e conservation and restoration of cave paintings and stone-built, ancient structures such as pyramids, cathedrals and monuments. (Author)

  4. Comercio y crecimiento económico en Baja California

    OpenAIRE

    Juan Manuel Ocegueda Hernández

    2005-01-01

    En este trabajo se estima la tasa de crecimiento de equilibrio comercial de Baja California siguiendo el enfoque desarrollado por Kaldor (1970), Dixon y Thirlwall (1975) y Thirlwall y Dixon (1979), en el que se destaca la importancia de las exportaciones y de la especialización en actividades con altos multiplicadores dinámicos de la demanda externa y con rendimientos crecientes a escala, en la determinación de las diferencias en tasas de crecimiento regionales. Se demuestra la...

  5. Whole genome sequencing of Mycobacterium bovis to obtain molecular fingerprints in human and cattle isolates from Baja California, Mexico.

    Science.gov (United States)

    Sandoval-Azuara, Sarai Estrella; Muñiz-Salazar, Raquel; Perea-Jacobo, Ricardo; Robbe-Austerman, Suelee; Perera-Ortiz, Alejandro; López-Valencia, Gilberto; Bravo, Doris M; Sanchez-Flores, Alejandro; Miranda-Guzmán, Daniela; Flores-López, Carlos Alberto; Zenteno-Cuevas, Roberto; Laniado-Laborín, Rafael; de la Cruz, Fabiola Lafarga; Stuber, Tod P

    2017-10-01

    To determine genetic diversity by comparing the whole genome sequences of cattle and human Mycobacterium bovis isolates from Baja California. A whole genome sequencing strategy was used to obtain the molecular fingerprints of 172 isolates of M. bovis obtained from Baja California, Mexico; 155 isolates were from cattle and 17 isolates were from humans. Spoligotypes were characterized in silico and single nucleotide polymorphism (SNP) differences between the isolates were evaluated. A total of 12 M. bovis spoligotype patterns were identified in cattle and humans. Two predominant spoligotypes patterns were seen in both cattle and humans: SB0145 and SB1040. The SB0145 spoligotype represented 59% of cattle isolates (n=91) and 65% of human isolates (n=11), while the SB1040 spoligotype represented 30% of cattle isolates (n=47) and 30% of human isolates (n=5). When evaluating SNP differences, the human isolates were intimately intertwined with the cattle isolates. All isolates from humans had spoligotype patterns that matched those observed in the cattle isolates, and all human isolates shared common ancestors with cattle in Baja California based on SNP analysis. This suggests that most human tuberculosis caused by M. bovis in Baja California is derived from M. bovis circulating in Baja California cattle. These results reinforce the importance of bovine tuberculosis surveillance and control in this region. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Sector externo, crecimiento económico y bienestar en Baja California: 1970-1988

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    Jorge García Montaño

    1990-05-01

    Full Text Available El presente trabajo tiene el objetivo de presentar los efectos del desarrollo del sector externo de Baja California en el crecimiento de la economía local y en relación con algunos indicadores del bienestar social. También se estudian algunos indicadores nacionales comparativos entre la entidad y los promedios nacionales, tal que permitan ubicar las especificidades del desarrollo de Baja California. El trabajo se divide en varios apartados: ciclos económicos, comportamiento del sector externo y sus relaciones con el producto interno bruto y la inflación. Todas estas variables interactúan en este estudio macroeconómico regional.La conclusión, hace referencia a que en Baja California el sector externo cumple el papel determinante para el crecimiento económico y el bienestar social; por lo tanto, cualquier trastorno negativo en sus variables desagregadas impacta inmediatamente las tasas de crecimiento y los niveles de vida de la población bajaca1iforniana, fundamentalmente los cambios extraordinarios del tipo de cambio peso-dólar y los ajustes de las políticas en comercio exterior. De ahí la actualidad del estudio, dado que el Tratado de Libre Comercio de México con Estados Unidos y Canadá tendrá, seguramente, importantes impactos en la entidad.

  7. Geophysical characterization of subaerial hydrothermal manifestations in Punta Banda, Baja California, Mexico.

    Science.gov (United States)

    Flores-Marquez, L.; Prol-Ledesma, R. M.; Arango, C.; Canet, C.

    2009-04-01

    Important growth of population in Baja California Peninsula has triggered the need for energy and fresh water. The most sustainable possibility for increasing the availability of fresh water is the use of renewable energy sources in desalination plants. The abundance of geothermal manifestations in the peninsula provides a reliable energy source for desalination purposes. Geothermal development of the Baja California Peninsula dates from the 70's, when the Cerro Prieto geothermal field started producing electricity. Two important cities, Tijuana and Ensenada, are located in the north-western area of Baja California. The city of Ensenada has a desalination plant that is due to be replaced and the geothermal resources of the area could be an option for the new desalination plant. Punta Banda, a region near Ensenada, was specially investigated to determine its geothermal potential. Subaerial springs and the submarine vents were sampled and studied in this work, also geological and geochemical studies were performed, moreover geoelectrical surveys were accomplished to characterize the hydrothermal system at depth. Even though saline intrusion is a severe problem in Ensenada (TDS higher than 3000), thermal springs away from the coast and coastal springs have salinities lower than sea water. According to the geoelectrical models obtained from profiles, the inferred conductive features can be related to thermal anomalies. The existence of hot springs located along a trend suggests that the dynamic of the thermal fluid is restricted by secondary faults.

  8. Phylogeography and Ecological Niche Modeling of the Desert Iguana (Dipsosaurus dorsalis, Baird & Girard 1852) in the Baja California Peninsula.

    Science.gov (United States)

    Valdivia-Carrillo, Tania; García-De León, Francisco J; Blázquez, Ma Carmen; Gutiérrez-Flores, Carina; González Zamorano, Patricia

    2017-09-01

    Understanding the factors that explain the patterns of genetic structure or phylogeographic breaks at an intraspecific level is key to inferring the mechanisms of population differentiation in its early stages. These topics have been well studied in the Baja California region, with vicariance and the dispersal ability of individuals being the prevailing hypothesis for phylogeographic breaks. In this study, we evaluated the phylogeographic patterns in the desert iguana (Dipsosaurus dorsalis), a species with a recent history in the region and spatial variation in life history traits. We analyzed a total of 307 individuals collected throughout 19 localities across the Baja California Peninsula with 15 microsatellite DNA markers. Our data reveal the existence of 3 geographically discrete genetic populations with moderate gene flow and an isolation-by-distance pattern presumably produced by the occurrence of a refugium in the Cape region during the Pleistocene Last Glacial Maximum. Bayesian methods and ecological niche modeling were used to assess the relationship between population genetic structure and present and past climatic preferences of the desert iguana. We found that the present climatic heterogeneity of the Baja California Peninsula has a marked influence on the population genetic structure of the species, suggesting that there are alternative explanations besides vicariance. The information obtained in this study provides data allowing a better understanding of how historical population processes in the Baja California Peninsula can be understood from an ecological perspective. © The American Genetic Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Coastal submarine hydrothermal activity off northern Baja California

    International Nuclear Information System (INIS)

    Vidal, V.M.V.; Vidal, F.V.; Isaacs, J.D.; Young, D.R.

    1978-01-01

    In situ observations of submarine hydrothermal activity have been conducted in Punta Banda. Baja Califronia, Mexico, approximately 400 m from the coast and at a seawater depth of 30 m. The hydrothermal activity occurs within the Agua Blanca Fault, a major transverse structure of Northern Baja California. Hot springwater samples have been collected and analyzed. Marked differences exist between the submarine hot springwater, local land hot springwaters, groundwater, and local seawater. SiO 2 , HCO 3 , Ca, K, Li, B, Ba, Rb, Fe, Mn, As, and Zn are enriched in the submarine hot springwater, while Cl, Na, So 4 2 , Mg, Cu, Ni, Cd, Cr, and perhaps Pb are depleted in relation to average and local seawater values. Very high temperatures, at the hydrothermal vents, have been recorded (102 0 C at 4-atm pressure). Visible gaseous emanations rich in CH 4 and N 2 coexist with the hydrothermal solutions. Metalliferous deposits, pyrite, have been encountered with high concentrations of Fe, S, Si, Al, Mn, Ca, and the volatile elements As, Hg, Sb, and Tl, X ray dispersive spectrometry (1500-ppm detection limit). X ray diffraction, and scanning electron microscopy of the isolated metalliferous precipitates indicate that the principal products of precipitation are pyrite and gypsum accompanied by minor amounts of amorphous material containing Si and Al. Chemical analyses and XRD of the reference control rocks of the locality (volcanics) versus the hydrothermally altered rocks indicate that high-temperature and high-pressure water-rock interactions can in part explain the water chemistry characteristics of the submarine hydrothermal waters. Their long residence time, the occurrence of an extensive marine sedimentary formation, their association with CH 4 and their similarities with connate waters of oil and gas fields suggest that another component of their genesis could be in cation exchange reactions within deeply buried sediments of marine origin

  10. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Del Toro, Ligeia [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico); Heckel, Gisela [Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico) and Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860 (Mexico)]. E-mail: gheckel@cicese.mx; Camacho-Ibar, Victor F. [Instituto de Investigaciones Oceanologicas, UABC, Apdo. Postal 453, Ensenada, Baja California 22860 (Mexico); Schramm, Yolanda [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico)

    2006-07-15

    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. {sigma}DDTs were the dominant group (geometric mean 3.8 {mu}g/g lipid weight), followed by polychlorinated biphenyls ({sigma}PCBs, 2.96 {mu}g/g), chlordanes (0.12 {mu}g/g) and hexachlorocyclohexanes (0.06 {mu}g/g). The {sigma}DDTs/{sigma}PCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA.

  11. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    International Nuclear Information System (INIS)

    Del Toro, Ligeia; Heckel, Gisela; Camacho-Ibar, Victor F.; Schramm, Yolanda

    2006-01-01

    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. ΣDDTs were the dominant group (geometric mean 3.8 μg/g lipid weight), followed by polychlorinated biphenyls (ΣPCBs, 2.96 μg/g), chlordanes (0.12 μg/g) and hexachlorocyclohexanes (0.06 μg/g). The ΣDDTs/ΣPCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA

  12. Preliminary assessment of biodiesel generation from meat industry residues in Baja California, Mexico

    International Nuclear Information System (INIS)

    Toscano, Lydia; Montero, Gisela; Stoytcheva, Margarita; Campbell, Hector; Lambert, Alejandro

    2011-01-01

    Oil derived fuels constituted a main energy source during the last fifty years, although their high price limited their accessibility. Prospective studies indicated that economic and environmental problems promoted biodiesel production using biomass and residues like animal fat, along with meat and bones, among others. The regional inventory of the available fat in meat industry, as well as the estimation of the biodiesel potential production demonstrated that the biodiesel generated from animal fat, combined with diesel from oil in a 2% biodiesel blend could power 25% of the trucks and passenger vehicles registered in 2007 in Baja California, Mexico. (author)

  13. Rational reference levels for Pacific Coast radioactive pollution studies supplied by samples from northern Baja California

    International Nuclear Information System (INIS)

    Folsom, T.R.

    1974-01-01

    Background levels of radioactivity in the marine environment along the Pacific Coast are at present extremely low. However, these certainly will rise along with the growth of coastal populations and with the increased use of nuclear energy. It would be desirable to anticipate where and how fast concentrations of artificial radioactivities may reach unacceptable levels in coastal water. Successful prediction of this sort requires knowing how the ocean responds, in given regions, to specific inputs. Fortunately, some of the fate of a large class of radioactive pollutants that must be faced in the future may be inferred from careful studies during the past 20 years of the behavior of certain constituents of nuclear fallout that have entered the ocean along the coasts of California and Baja California. (CH)

  14. Demographic trajectories of Baja California and California, 1900-2000. Contrasts and parallelisms

    Directory of Open Access Journals (Sweden)

    David Piñera Ramírez

    2012-07-01

    Full Text Available The purpose is to analyze migration processes that have occurred in two neighboring states, pointing out the characteristics acquired in each of them, especially regarding their origin and type of labor relations they have produced. Therefore, the migration as the thematic axis and following the guidelines of comparative history, it is shown that both in California and in Baja California, migration flows have played a fundamental role. The comparative appro­ach also leads to the search for similarities and differences represented in different moments, such as the impact of "Prohibition", the Great Depression and two World Wars, or specific phenomena as the arrival of the railroad. But above all, the common thread is migration with its two key issues mentioned above, the origin of migration flows and labor relations that they have generated in the two Californias.

  15. Desarrollo humano en el noroeste de México: un análisis comparativo de los estados de Sonora, Baja California y Baja California Sur, 1995-2005

    Directory of Open Access Journals (Sweden)

    Francisco José Zamudio Sánchez

    2009-01-01

    Full Text Available Este artículo aborda el desarrollo humano en Sonora, Baja California y Baja California Sur. Se estimaron los valores de cuatro índices: desarrollo humano con producto interno bruto, desarrollo humano con servicios, con género e inequidad; además de curvas de calidad estatal y municipal.Aunque los valores ubican a Baja California Sur en la mejor posición de los indicadores de desarrollo humano y después a Sonora; Baja California ocupa el mejor sitio en equidad en el país.

  16. Proceedings of the Binational Conference on Libraries in California and Baja California (1st, Tijuana, Baja California, Mexico, January 13-14, 1984) = Memorias de la Primera Conferencia Binacional de Bibliotecas de las Californias.

    Science.gov (United States)

    Ayala, Marta Stiefel, Ed.; And Others

    This document includes the text of presentations given at the First Binational Conference on Libraries in California and Baja California, as well as minutes from four roundtables held at the conference. Following a prologue and a brief background on the conference, the following presentations are included: (1) "State Support for Public…

  17. Desarrollo, identidad cultural y turismo en los oasis de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Alexandra Sauvage

    2013-01-01

    Full Text Available This article provides an analysis of the integration of San Miguel and San José de Comondú to the process of economic globalization lived in Baja California Sur, in northwest Mexico. These rural communities are located in one of the largest oasis in the arid Baja California peninsula and face the risks of cultural commodification from the growth of the real estate and tourism sectors. In a context of diffuse integration to new markets and a weak local community involvement in the initiatives to foster economic growth, without a cultural policy that involves comundeños in defining their own heritage and the benefits of its use, the goal of local development attached to the recent public policies is questionable. We propose that a cultural policy should form the backbone of the development programmes now being elaborated, so as to articulate regional development needs with cultural heritage conservation, seeking to avoid the simple commodification of local traditions and recognizing the role of the local community in (redefining their cultural values.

  18. The invented Baja California: visions of a Mexican territory in the middle 20th century

    Directory of Open Access Journals (Sweden)

    Héctor Mendoza Vargas

    2014-02-01

    Full Text Available This article examines the travels of Peter Gerhard and Ángel Bassols Batalla through the Baja California in the 1950s from a comparative perspective. From the theo-retical viewpoints of the history of geography and the geographical journey as sources of information and working method in situ, the observation and empirical knowledge of the territory are established. The traveling style of both authors involves a cultural consideration, since an invented space emerges before their eyes from their own experience in the peninsula. As a traveler, Peter Gerhard journeyed the peninsula seeking the ancient missions that distinguished Baja California. That is why he organized and integrated the information in a guide, in collaboration with Howard E. Gulick. He conceived the guide for tourists of the United States interested in this region so close to their country. Published in 1956, the guide became the most complete instrument for vacationists in general, and also for sport fishermen, hunters, explorers and campers.

  19. Stable isotope composition of surface and groundwater in Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, Thomas G. [CICESE, Carret. Ensenada-Tijuana No 3819, Ensenada 22860 (Mexico); Frommen, Theresa [FU Berlin Malteserstr. 74-100, 12249 Berlin (Germany)

    2013-07-01

    Based on a total of 135 stable isotope analysis (δ{sup 18}O, δD) carried out on surface and groundwater samples, as well as on rainwater samples between 2004 and 2011 in 5 different regions in Baja California, an isotopic evaluation of the region was established. The results showed a depletion gradient of -0.25 0/00 δ{sup 18}O per 100 m rise in elevation throughout the study area. Considering an unaltered δ{sup 18}O signature for the thermal springs, the recharge areas of these waters are at elevations over 1400 m outside of the present watersheds, indicating the presence of regional flow systems next to the local flow regime feeding the cold springs and wells. The Mesa de Andrade area has a completely different signature with values of -105 for δ{sup 18}O and -13 for δD. (authors)

  20. Stable isotope composition of surface and groundwater in Baja California, Mexico

    International Nuclear Information System (INIS)

    Kretzschmar, Thomas G.; Frommen, Theresa

    2013-01-01

    Based on a total of 135 stable isotope analysis (δ 18 O, δD) carried out on surface and groundwater samples, as well as on rainwater samples between 2004 and 2011 in 5 different regions in Baja California, an isotopic evaluation of the region was established. The results showed a depletion gradient of -0.25 0/00 δ 18 O per 100 m rise in elevation throughout the study area. Considering an unaltered δ 18 O signature for the thermal springs, the recharge areas of these waters are at elevations over 1400 m outside of the present watersheds, indicating the presence of regional flow systems next to the local flow regime feeding the cold springs and wells. The Mesa de Andrade area has a completely different signature with values of -105 for δ 18 O and -13 for δD. (authors)

  1. Demographic Decline and Growth in Baja California during the Eighteenth and Nineteenth Centuries. A Look at Census and Local Registers

    Directory of Open Access Journals (Sweden)

    Dení Trejo Barajas

    2005-01-01

    Full Text Available The indigenous population of Baja California was  reduced  significantly  during the missionary period. However, in the  early­ nineteenth century the  declining demographic trend that led these peoples to extinction began to revert. The immigration of groups  that settled in the  former missions, in nearby ranches, along  the  coasts  and  in  the  mining regions  in  the   Southern part of the península gave place  to an unstable but important demographic growth in the region. This work reviews this de­mographic rocess in its different stages, by  analyzing the  cen­sus and regtsters of religious and civil  authorities of  the  Baja California península.

  2. Fish larvae in Bahía Sebastián Vizcaíno and the adjacent oceanic region, Baja California, México.

    Directory of Open Access Journals (Sweden)

    Jiménez–Rosenberg, S. P. A.

    2007-01-01

    Full Text Available The taxonomic composition of the fish larvae assemblage of Bahía Sebastián Vizcaíno and the adjacentoceanic region is presented based on oblique zooplankton hauls made during 12 oceanographic surveys between fall1997 and fall 2000. In total, 186 taxa representing 71 families were collected. Myctophidae, Phosichthyidae, andEngraulidae were the most abundant during winter and Myctophidae, Merlucciidae, and Bathylagidae during spring. Insummer and fall Phosichthyidae and Myctophidae were the most abundant. During 1999 and 2000, seasonal variabilitywas identified in the area by the fish larvae composition, defining winter and fall as a low diversity period and springand summer as a high diversity period. Interannual variability was detected with an El Niño event, with higher larvalabundances of tropical and subtropical taxa, and a La Niña event, with high abundances of larvae of Engraulis mordax.

  3. Volcanic materials superconductivity in desert areas of the states of Sonora and Baja California

    International Nuclear Information System (INIS)

    Holguín, Aldo

    2017-01-01

    Research was conducted to find materials in their natural state at room temperature and exhibit the effects of superconductivity in the volcanic region of deserts Altar in Sonora and Baja California Norte. 100 were collected at random samples of materials from different parts of the region and underwent tests to determine their electromagnetic parameters of electrical resistance, magnetism, temperature and conductivity. Only it has been found that the effects of superconductivity in them is only present at very low temperatures corroborating what has been done in other investigations, however no indication that there is a material or combination of materials that can produce the effects of superconductivity other temperatures so it is suggested to continue the search for such materials and / or develop a technique at room temperature to allow mimic the behavior of atoms when superconductivity occurs at. (paper)

  4. Autónoma de Baja California, México

    Directory of Open Access Journals (Sweden)

    Isaac Cruz Estrada

    2017-01-01

    Full Text Available En la actualidad, la constante evolución de las TIC son un reto para las instituciones universitarias, ya que en su velocidad de cambio se pueden exhibir las dificultades para adaptarse y poder abastecer a los estudiantes del uso adecuado de los dispositivos electrónicos y su entendimiento con el Internet. De este modo, se llevó a cabo un estudio descriptivo para caracterizar la forma en que los universitarios en Turismo están utilizando las tecnologías y conduzca a identificar los elementos y hábitos de estudio que tiene que tomar en cuenta la institución académica, en su papel de contribuir para aprovechar las bondades de los medios electrónicos que están presente en el entorno de los universitarios. Se aplicaron 138 encuestas de 215 estudiantes de la Licenciatura en Gestión Turística de la Facultad de Turismo y Mercadotecnia de la Universidad Autónoma de Baja California, considerando 95% de confianza y 5% de error admitido. De los resultados a destacar se encontró que, los estudiantes están adoptando con frecuencia el uso de dispositivos móviles para tomar notas en las clases, de este modo más del 80% mencionan tener un buen manejo de Internet y las redes sociales, además es frecuente la utilización de la mensajería instantánea para comunicarse. Sin embargo, al usar Internet para buscar información mediante bibliotecas virtuales no se tiene un resultado positivo, lo que conduce a la unidad académica a formar al estudiante en éste y otros aspectos en beneficio del aprovechamiento de los medios digitales, que a su vez conduzca a adaptarse a la modalidad virtual, que pueda satisfacer las necesidades actuales en la educación universitaria.

  5. Distribution, genetic structure, and conservation status of the rare microendemic species, Guaiacum unijugum (Zygophyllaceae in the Cape Region of Baja California, Mexico Distribución, estructura genética y conservación de la especie microendémica Guaiacum unijugum (Zygophyllaceae en la región de los Cabos de Baja California, México

    Directory of Open Access Journals (Sweden)

    Ross A. McCauley

    2010-12-01

    Full Text Available Guaiacum unijugum is a rare shrub endemic to a 70 km stretch of coastline extending east from San José del Cabo in Baja California and is the least well-known of the 4 species of Guaiacum in Mexico. To increase our knowledge of this species and assess its conservation status we surveyed the extent of occurrence using both herbarium material and field work, assessed levels of genetic diversity, determined its phylogenetic relationships, and completed an evaluation of risk of extinction (MER. Herbarium material identified 5 known localities of occurrence with field work verifying the continued persistence of 4 of these with an additional site discovered. Genetic analysis across the small range using 17 microsatellite loci showed very low levels of genetic diversity with a mean expected heterozygosity (H E of 0.162 over all polymorphic loci. Most loci were found to be monomorphic and genetic divergence was small, maintained by the presence of rare private alleles in widely-separated populations. Phylogenetic analysis indicated a sister group relationship to G. coulteri along the Pacific coast suggesting vicariance for the origin and occurrence of G. unijugum. The unique evolutionary history coupled with current small population sizes warrants increased conservation via listing as a critically endangered species.Guaiacum unijugum es un arbusto endémico en un área de aproximadamente 70 km en la región de Los Cabos, Baja California Sur, siendo la menos estudiada de las 4 especies de Guaiacum en México. Para incrementar nuestro conocimiento sobre esta especie y determinar su estatus de conservación se realizó un censo de sus poblaciones determinándose su estructura genética, su relación filogenética con otros miembros del género y se calculó su riesgo de extinción (MER. La revisión de material de herbario, confirmó la presencia de 4 poblaciones a las que se sumó el hallazgo de 1 más. Mediante el uso de 17 loci de microsatélites se

  6. Gender and abuse: Partner violence among young people in Baja California

    Directory of Open Access Journals (Sweden)

    Humberto González Galbán

    2010-07-01

    Full Text Available Domestic violence or spousal abuse, largely determined by the existing traditional gender roles, is the issue discussed in this article, which is focusing on the special case of young people of the state of Baja California. During the search of the conditional agents of this social process, there were valued psychological and socio–demographic variables, such as family violence during childhood, immigration status, educational level and age, all these variables were separated by the gender and age (rank 18–29 of the sudied sample.Considering the information provided of the database used; The Survey of Adolescent Reproductive Health of Baja California 2006, it is described and analyzed in this research, several indicators, all of them related with important issues which affect a part of the young population of Baja California, regardless the lack of information and almost non previous research about this theme.

  7. Migración por empleo en México. La experiencia de Baja California entre 2008 y 2012

    Directory of Open Access Journals (Sweden)

    Alejandro Mungaray Lagarda

    2014-01-01

    Full Text Available Para entender el reto del empleo que enfrenta México, en un contexto de diversidad regional, se ofrece una expli - cación a la paradoja actual de crecimiento del empleo y de la tasa de desempleo que ocurre al mismo tiempo en Baja California. Mediante la estimación de un modelo de datos de panel, se genera evidencia de que los flujos migratorios del interior del país son mayores que el aumento de la po - blación ocupada, debido a que tanto ésta como los salarios y el nivel de competitividad social de Baja California in - fluyen de manera directa en las decisiones de las personas para moverse a dicha entidad.

  8. Monomorphic pathogens: The case of Candidatus Xenohaliotis californiensis from abalone in California, USA and Baja California, Mexico.

    Science.gov (United States)

    Cicala, Francesco; Moore, James D; Cáceres-Martínez, Jorge; Del Río-Portilla, Miguel A; Hernández-Rodríguez, Mónica; Vásquez-Yeomans, Rebeca; Rocha-Olivares, Axayácatl

    2018-05-01

    Withering syndrome (WS) is a chronic wasting disease affecting abalone species attributed to the pathogen Candidatus Xenohaliotis californiensis (CXc). Wild populations of blue (Haliotis fulgens) and yellow (H. corrugata) abalone have experienced unusual mortality rates since 2009 off the peninsula of Baja California and WS has been hypothesized as a possible cause. Currently, little information is available about the genetic diversity of CXc and particularly the possible existence of strains differing in pathogenicity. In a recent phylogenetic analysis, we characterized five coding genes from this rickettsial pathogen. Here, we analyze those genes and two additional intergenic non-coding regions following multi-locus sequence typing (MLST) and multi-spacer typing (MST) approaches to assess the genetic variability of CXc and its relationship with blue, yellow and red (H. rufescens) abalone. Moreover, we used 16S rRNA pyrosequencing reads from gut microbiomes of blue and yellow abalone to complete the genetic characterization of this prokaryote. The presence of CXc was investigated in more than 150 abalone of the three species; furthermore, a total of 385 DNA sequences and 7117 16S rRNA reads from Candidatus Xenohaliotis californiensis were used to evaluate its population genetic structure. Our findings suggest the absence of polymorphism in the DNA sequences of analyzed loci and the presence of a single lineage of CXc infecting abalone from California (USA) and Baja California (Mexico). We posit that the absence of genetic variably in this marine rickettsia may be the result of evolutionary and ecological processes. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Use of small reactors as an alternative to supply electricity to Baja California Sur; Uso de reactores pequenos como alternativa de suministro de electricidad para Baja California Sur

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, G.; Portes, E.; Ramirez, J. R. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Ortega, G., E-mail: gustavo.alonso@inin.gob.mx [Comision Federal de Electricidad, Rio Rodano No. 14, 06500 Ciudad de Mexico (Mexico)

    2016-09-15

    The state of Baja California Sur (Mexico) does not form part of the national interconnected electrical system of the country, reason why is local its electrical power supply; one of the alternatives to cover future demands is the use of gas-based combined cycles, which presents the additional problem of including a high price for gas transportation in its costs. In order to reduce total costs, including investment, fuels and operation and maintenance in the operation of the Baja California Sur state electricity system in the coming years, mainly due to the estimated natural gas cost order of $11.50 dollars per million BTU, a proposal is presented to reduce the costs of the electrical system by replacing the necessary combined cycles with the new Small Modular Reactor type nuclear reactors, this alternative is economically competitive. (Author)

  10. Health Care among the Kumiai Indians of Baja California, Mexico: Structural and Social Barriers

    Science.gov (United States)

    Fleuriet, K. Jill

    2009-01-01

    In this article, the author documents the illness and health care problems facing indigenous communities in Baja California, Mexico, by using ethnographic data from research she conducted from 1999 to 2001 with rural, indigenous Kumiai and with their primary health care providers in urban Ensenada. The author contends that barriers to care are…

  11. Especialización industrial y desarrollo empresarial en Baja California

    Directory of Open Access Journals (Sweden)

    Alejandro Mungaray

    2003-01-01

    Full Text Available La especialización industrial en Baja California en el sector de productos metálicos, maquina ria y equipo, s e asocia en economías de redes por interacciones de costos entre las grandes empresas asiáticas y del sur de California que conviven en la región conforme a las nuevas reglas del TLCAN y el fuerte peso de la subcontratación y las operaciones intraindustriales. En este contexto, se evalúa el impacto sobre la vida económica y social de las empresas para comprobar si la perspectiva de bienestar social a través del empleo, resultado de la estrategia industrial de atraer inversión extranjera directa, tiene que ver más con la discriminación salarial que con la productividad, y si los incrementos salariales están influidos por alzas en productividad y la especialización. Se parte de que el bienestar es clave en la estrategia de política industrial regional con objetivos competitivos para el desarrollo regional y empresarial, donde este último se inhibe ante la limitada estrategia estatal .

  12. Shallow magnetic inclinations in the Cretaceous Valle Group, Baja California: remagnetization, compaction, or terrane translation?

    Science.gov (United States)

    Smith, Douglas P.; Busby, Cathy J.

    1993-10-01

    Paleomagnetic data from Albian to Turonian sedimentary rocks on Cedros Island, Mexico (28.2° N, 115.2° W) support the interpretation that Cretaceous rocks of western Baja California have moved farther northward than the 3° of latitude assignable to Neogene oblique rifting in the Gulf of California. Averaged Cretaceous paleomagnetic results from Cedros Island support 20 ± 10° of northward displacement and 14 ± 7° of clockwise rotation with respect to cratonic North America. Positive field stability tests from the Vizcaino terrane substantiate a mid-Cretaceous age for the high-temperature characteristic remanent magnetization in mid-Cretaceous strata. Therefore coincidence of characteristic magnetization directions and the expected Quaternary axial dipole direction is not due to post mid-Cretaceous remagnetization. A slump test performed on internally coherent, intrabasinal slump blocks within a paleontologically dated olistostrome demonstrates a mid-Cretaceous age of magnetization in the Valle Group. The in situ high-temperature natural remanent magnetization directions markedly diverge from the expected Quaternary axial dipole, indicating that the characteristic, high-temperature magnetization was acquired prior to intrabasinal slumping. Early acquisition of the characteristic magnetization is also supported by a regional attitude test involving three localities in coherent mid-Cretaceous Valle Group strata. Paleomagnetic inclinations in mudstone are not different from those in sandstone, indicating that burial compaction did not bias the results toward shallow inclinations in the Vizcaino terrane.

  13. Análisis de los flujos turísticos en el corredor Los Cabos, Baja California Sur

    Directory of Open Access Journals (Sweden)

    Álvaro López López

    2001-09-01

    Full Text Available The Los Cabos corridor is one of the most dynamic tourism spaces in Mexico. In, around and towards this corridor, intense flows of tourists, migrants, merchandises and information takes place. Diverse in their territorial Impact as they are, most of them act as a link between the southernmost tip of the Baja peninsula and the state of California, in the United States. This is provoking a dissociation of this region of Mexico in its relation with the rest of the country that, to a certain extent, leads to a loss of national sovereignty.

  14. [Distribution of aquatic and raptor birds in a freshwater artificial pond of Baja California Sur, Mexico].

    Science.gov (United States)

    Castillo-Guerrero, J A; Carmona, R

    2001-01-01

    We determined the taxonomic composition and spatial-temporal distribution of aquatic and raptor birds in a freshwater artificial pond of El Centenario, Baja California Sur, México, during 24 biweekly censuses (April, 1998 to March, 1999). The pond is particularly attractive for birds because of its variety of food items. A total 25,563 records of 69 species were done, among them the first report of Chlidonias niger and Phalaropus tricolor for the region. Species richness and abundance were determined for the migrant component, mostly Anatidae (16 species and 55.6% of the total abundance) and shorebirds (18 species and 13.3%). The greater number of species and individuals was in C the deepest and more heterogeneous section of the pond. The most important species was Oxyura jamaicensis (30% of the total observed individuals), with highest abundance in the peninsula. The artificial pond presented an atypical and distinct ornithological composition because it is located in an arid region, and acts as a resting site for migrant birds. The site included species that usually live in freshwater and coastal areas, a characteristic reflected in their high richness. It contributes noticeably to the local avian biodiversity.

  15. Baja California dentro del contexto de la migración de la frontera norte de México

    Directory of Open Access Journals (Sweden)

    Margarita Barajas Tinoco

    1993-01-01

    Full Text Available En este trabajo se destaca el papel del fenómeno migratorio en la conformación poblacional de la frontera norte de México (PNM en general y de Baja California en particular. Se describe el panorama de la inmigración interna a Baja California, haciendo especial énfasis en el perfil de la inmigración de la década de los ochenta, misma que se encuentra asociada con las oportunidades económicas de empleo que la entidad presentó en un periodo de crisis nacional. Las fuentes de información utilizadas son el Censo de Población, 1990, para Baja California y La Encuesta Continua de Migración de Baja California (ECMBC, 1989

  16. Migración y estructuración territorial del estado de Baja California

    Directory of Open Access Journals (Sweden)

    Alba Adriana Wells Ayón

    1990-05-01

    Full Text Available En este ensayo se considera a Baja California como un producto territorial del fenómeno migratorio, y se realiza una descripción general de la dinámica poblacional que ha experimentado el estado a partir de los constantes movimientos migratorios en destacadas áreas de su espacio geográfico. Demostrando así la existencia en Baja California de movilidades geográficas de población constituidas principalmente por tres tipos de movimientos: el interno, el interurbano, y el internacional; además de encontrar la presencia de cadenas de migración interna basadas en sistemas de reciprocidad social. Finalmente, se proporcionan las conclusiones del trabajo.

  17. Status and Causes of Soil Salinization of Irrigated Agricultural Lands in Southern Baja California,Mexico

    International Nuclear Information System (INIS)

    Endo, T.; Yamamoto, S.; Fujiyama, H.; Honna, T.; Larrinaga, J.A.

    2011-01-01

    Selected farmlands in southern Baja California, Mexico, were surveyed to determine the levels and the causes of salinization/sodication in irrigated agricultural soil. The salt dynamics observed in profiles differed from farm to farm. Low EC and high ph levels were observed in the profiles of sandy fields, because the salt composition of these soils can easily change when salts are leached by irrigation water that contains carbonates of sodium. On the other hand, high levels of salinity and sodicity were observed in the soils of clayey fields. Soil salinization/sodication is complexly interrelated with soil characteristics, the amount and composition of salts in the soil, the quantity and quality of irrigation water applied, and the irrigation methods used. Our findings indicate that irrigation water in Baja California should be supplied at a rate that is sufficient to meet crop requirements without exacerbating salt accumulation.

  18. Use of small reactors as an alternative to supply electricity to Baja California Sur

    International Nuclear Information System (INIS)

    Alonso, G.; Portes, E.; Ramirez, J. R.; Ortega, G.

    2016-09-01

    The state of Baja California Sur (Mexico) does not form part of the national interconnected electrical system of the country, reason why is local its electrical power supply; one of the alternatives to cover future demands is the use of gas-based combined cycles, which presents the additional problem of including a high price for gas transportation in its costs. In order to reduce total costs, including investment, fuels and operation and maintenance in the operation of the Baja California Sur state electricity system in the coming years, mainly due to the estimated natural gas cost order of $11.50 dollars per million BTU, a proposal is presented to reduce the costs of the electrical system by replacing the necessary combined cycles with the new Small Modular Reactor type nuclear reactors, this alternative is economically competitive. (Author)

  19. PIXE analysis of cave sediments, prehispanic paintings and obsidian cutting tools from Baja California Sur caves

    International Nuclear Information System (INIS)

    Miranda, J.; Oliver, A.; Dacal, A.; Ruvalcaba, J.L.; Cruz, F.; Ortiz, M.E.; Vinas, R.

    1993-01-01

    Elemental PIXE analysis of cave sediments, minerals, pigments of the prehispanic paintings and obsidian cutting tools from caves in Baja California Sur has been carried out with a 0.7 MeV proton beam. The elements analysed in this sample set (Al to Co) provide an idea of the environment of the caves. The obsidian data analysis suggests that the human communities who made these painting used more than one obsidian source to manufacture cutting tools. (orig.)

  20. Epidemics which never came: yellow fever (1883) and bubonic plague (1902-1903) in Baja California

    Science.gov (United States)

    Fierros-Hernández, Arturo; Ayala-Zúñiga, Alejandro

    2018-01-01

    This paper seeks to clarify the epidemic panorama that was generated in Baja California in the late nineteenth and early twentieth 20 th century’s, specifically that occurred in 1883 and 1902, years in which it is claimed occurred epidemics of yellow fever and bubonic plague respectively. However, as demonstrated in our study they never occurred due to social-demographic conditions in the area. Copyright: © 2018 SecretarÍa de Salud.

  1. Red-on-granite rock painting in the Sierra de San Borja, Baja California

    Directory of Open Access Journals (Sweden)

    Hany Crosby

    1995-01-01

    Full Text Available New discoveries in Baja California, north of the 28th parallel contradict an old tradition, and push the boundary of the Great Mural paintings further north than had been previously suggested. The new area not only displays works akin in size and subject matter to their more southern counterparts, but also shows some changes in choice of surfaces, paint colors, and stylistic conventions. Seven sites are reported; many others are predicted.

  2. Wind Energy Assessment for Small Urban Communities in the Baja California Peninsula, Mexico

    OpenAIRE

    Quetzalcoatl Hernandez-Escobedo

    2016-01-01

    Mexico needs to exploit its renewable resources and many studies have determined the great renewable potential it has using wind energy. However it is necessary to calculate the amount of this resource for small urban communities, which in this country lack essential services such as electricity. This study is focused in the Baja California Peninsula, using GIS as a tool to identify small urban zones with higher wind power. For this work data was analyzed from meteorological stations and reco...

  3. New geologic slip rates for the Agua Blanca Fault, northern Baja California, Mexico

    Science.gov (United States)

    Gold, P. O.; Behr, W. M.; Fletcher, J. M.; Hinojosa-Corona, A.; Rockwell, T. K.

    2015-12-01

    Within the southern San Andreas transform plate boundary system, relatively little is known regarding active faulting in northern Baja California, Mexico, or offshore along the Inner Continental Borderland. The inner offshore system appears to be fed from the south by the Agua Blanca Fault (ABF), which strikes northwest across the Peninsular Ranges of northern Baja California. Therefore, the geologic slip rate for the ABF also provides a minimum slip rate estimate for the offshore system, which is connected to the north to faults in the Los Angeles region. Previous studies along the ABF determined slip rates of ~4-6 mm/yr (~10% of relative plate motion). However, these rates relied on imprecise age estimates and offset geomorphic features of a type that require these rates to be interpreted as minima, allowing for the possibility that the slip rate for the ABF may be greater. Although seismically quiescent, the surface trace of the ABF clearly reflects Holocene activity, and given its connectivity with the offshore fault system, more quantitative slip rates for the ABF are needed to better understand earthquake hazard for both US and Mexican coastal populations. Using newly acquired airborne LiDAR, we have mapped primary and secondary fault strands along the segmented western 70 km of the ABF. Minimal development has left the geomorphic record of surface slip remarkably well preserved, and we have identified abundant evidence meter to km scale right-lateral displacement, including new Late Quaternary slip rate sites. We verified potential reconstructions at each site during summer 2015 fieldwork, and selected an initial group of three high potential slip rate sites for detailed mapping and geochronologic analyses. Offset landforms, including fluvial terrace risers, alluvial fans, and incised channel fill deposits, record displacements of ~5-80 m, and based on minimal soil development, none appear older than early Holocene. To quantitatively constrain landform ages

  4. Remote sensing studies and morphotectonic investigations in an arid rift setting, Baja California, Mexico

    Science.gov (United States)

    El-Sobky, Hesham Farouk

    The Gulf of California and its surrounding land areas provide a classic example of recently rifted continental lithosphere. The recent tectonic history of eastern Baja California has been dominated by oblique rifting that began at ˜12 Ma. Thus, extensional tectonics, bedrock lithology, long-term climatic changes, and evolving surface processes have controlled the tectono-geomorphological evolution of the eastern part of the peninsula since that time. In this study, digital elevation data from the Shuttle Radar Topography Mission (SRTM) from Baja California were corrected and enhanced by replacing artifacts with real values that were derived using a series of geostatistical techniques. The next step was to generate accurate thematic geologic maps with high resolution (15-m) for the entire eastern coast of Baja California. The main approach that we used to clearly represent all the lithological units in the investigated area was objectoriented classification based on fuzzy logic theory. The area of study was divided into twenty-two blocks; each was classified independently on the basis of its own defined membership function. Overall accuracies were 89.6%, indicating that this approach was highly recommended over the most conventional classification techniques. The third step of this study was to assess the factors that affected the geomorphologic development along the eastern side of Baja California, where thirty-four drainage basins were extracted from a 15-m-resolution absolute digital elevation model (DEM). Thirty morphometric parameters were extracted; these parameters were then reduced using principal component analysis (PCA). Cluster analysis classification defined four major groups of basins. We extracted stream length-gradient indices, which highlight the differential rock uplift that has occurred along fault escarpments bounding the basins. Also, steepness and concavity indices were extracted for bedrock channels within the thirty-four drainage basins. The

  5. Wind Energy Assessment for Small Urban Communities in the Baja California Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Quetzalcoatl Hernandez-Escobedo

    2016-10-01

    Full Text Available Mexico needs to exploit its renewable resources and many studies have determined the great renewable potential it has using wind energy. However it is necessary to calculate the amount of this resource for small urban communities, which in this country lack essential services such as electricity. This study is focused in the Baja California Peninsula, using GIS as a tool to identify small urban zones with higher wind power. For this work data was analyzed from meteorological stations and recorded every 10 min for two years (2012–2014. Weibull distribution, linear regression, kriging interpolation, power and energy output and useful hours were calculated for each station. It was found that the total energy generated is 38,603,666 kWh per year and the mean of useful hours is 5220 h per year for the whole Peninsula. Maps of Wind Power Density (WPD show a good power per square meter, GIS shows the areas with the most wind power where it can be used i.e., the state of Baja California wind power can generate electricity for 12% of those communities, meanwhile for Baja California Sur, the electric power generation could electrify almost 25% of the total of small urban communities.

  6. [Distribution of aquatic birds in oxidation lagoons of La Paz city in South Baja California, Mexico].

    Science.gov (United States)

    Zamora-Orozco, Elvia Margarita; Carmona, Roberto; Brabata, Georgina

    2007-06-01

    Taxonomic composition, spatial and temporal distribution of aquatic birds in oxidation lagoons (LO) of La Paz city in south Baja California, Mexico, were determined during 24 censuses realized in two-week intervals (April/98-March/99). There are five lagoons of5 Ha each and 17 ha of terrains constantly flooded that serve as feeding areas for cattle and birds. One hundred twenty three species were observed, 75 of which were aquatic birds. A total of 46 041 observations were made (average 1 918 birds/census). Richness and abundance of aquatic birds were influenced mainly by migration of anatids and sandpipers. The first group had the greatest abundance due to its affinity towards fresh water bodies. The terrains were the favorite sites of dabbling ducks (Anas) and sandpipers. In contrast, two of the most abundant species (Oxyura jamaicensis, 12.5% of all species, and Fulica americana, 8.8 %) restricted their presence to the oxidation lagoons. LO presented a bird structure of its own and atypical, according to the dryness of the region.

  7. Mobile colposcopy in urban and underserved suburban areas in Baja California

    Science.gov (United States)

    Madiedo, Marta; Contreras, Sonia; Villalobos, Octavio; Kahn, Bruce S.; Safir, Amit; Levitz, David

    2016-03-01

    Cervical cancer is the leading cause of cancer death for women in low resource settings, often affecting the most economically disenfranchised segment of the population. The key challenge with cervical cancer is the lack of an effective screening program for many of the at-risk, difficult-to-reach women. Outreach programs that utilize mobile clinics to increase access to screening and care in Baja California have been developed. However, many barriers such as quality assurance, efficient referral remained a challenge in this region. Visualization-based co-tests together with cytology (Pap smears) as a primary screen have been proposed. Here, the mobile colposcope of the enhanced visual assessment (EVA) is used to capture an image immediately following a Pap smear. EVA images were reviewed by expert colposcopists. Initial or preliminary data from pilot services showed that Pap false positives and Pap false negatives maybe reduced by expert review of EVA images. This suggests that reviewing of EVA images may be instrumental in catching inaccurate Pap results, thereby improving care. Thus, there is a need to further explore the benefits of using EVA as additional information when conducting Pap smear screenings.

  8. Diversificación institucional y educación superior en Baja California en 2000

    Directory of Open Access Journals (Sweden)

    Patricia Moctezuma Hernández

    2005-01-01

    Full Text Available Este artículo aborda la diversificación del Sistema Estatal de Educación Superior (sees de Baja California, según la especialización económica regional existente y el proceso histórico de su conformación. El estudio concluye que la percepción de los usuarios sobre la educación superior es obra más bien de los esfuerzos individuales de las instituciones, que de la coordinación estatal, debido a que la opinión de los distintos actores sobre la definición de la política gubernamental es limitada. Para llegar a esta conclusión, se efectuó una evaluación del sees mediante una encuesta a estudiantes, y entrevistas a rectores y directores de las diferentes instituciones de educación superior (ies, de la entidad, durante el primer trimestre de 2000. Los criterios utilizados fueron la equidad y calidad.

  9. Triggered surface slips in southern California associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, earthquake

    Science.gov (United States)

    Rymer, Michael J.; Treiman, Jerome A.; Kendrick, Katherine J.; Lienkaemper, James J.; Weldon, Ray J.; Bilham, Roger; Wei, Meng; Fielding, Eric J.; Hernandez, Janis L.; Olson, Brian P.E.; Irvine, Pamela J.; Knepprath, Nichole; Sickler, Robert R.; Tong, Xiaopeng; Siem, Martin E.

    2011-01-01

    The April 4, 2010 (Mw7.2), El Mayor-Cucapah, Baja California, Mexico, earthquake is the strongest earthquake to shake the Salton Trough area since the 1992 (Mw7.3) Landers earthquake. Similar to the Landers event, ground-surface fracturing occurred on multiple faults in the trough. However, the 2010 event triggered surface slip on more faults in the central Salton Trough than previous earthquakes, including multiple faults in the Yuha Desert area, the southwestern section of the Salton Trough. In the central Salton Trough, surface fracturing occurred along the southern San Andreas, Coyote Creek, Superstition Hills, Wienert, Kalin, and Imperial Faults and along the Brawley Fault Zone, all of which are known to have slipped in historical time, either in primary (tectonic) slip and/or in triggered slip. Surface slip in association with the El Mayor-Cucapah earthquake is at least the eighth time in the past 42 years that a local or regional earthquake has triggered slip along faults in the central Salton Trough. In the southwestern part of the Salton Trough, surface fractures (triggered slip) occurred in a broad area of the Yuha Desert. This is the first time that triggered slip has been observed in the southwestern Salton Trough.

  10. Rheological properties of the lower crust and upper mantle beneath Baja California: a microstructural study of xenoliths from San Quintin

    Science.gov (United States)

    Van der Werf, Thomas F.; Chatzaras, Vasileios; Tikoff, Basil; Drury, Martyn R.

    2016-04-01

    Baja California is an active transtensional rift zone, which links the San Andreas Fault with the East Pacific Rise. The erupted basalts of the Holocene San Quintin volcanic field contain xenoliths, which sample the lower crust and upper mantle beneath Baja California. The aim of this research is to gain insight in the rheology of the lower crust and the upper mantle by investigating the xenolith microstructure. Microstructural observations have been used to determine the dominant deformation mechanisms. Differential stresses were estimated from recrystallized grain size piezometry of plagioclase and clinopyroxene for the lower crust and olivine for the upper mantle. The degree of deformation can be inferred from macroscopic foliations and the deformation microstructures. Preliminary results show that both the lower crust and the upper mantle have been affected by multiple stages of deformation and recrystallization. In addition the dominant deformation mechanism in both the lower crust and the upper mantle is dislocation creep based on the existence of strong crystallographic preferred orientations. The differential stress estimates for the lower crust are 10-29 MPa using plagioclase piezometry and 12-35 MPa using clinopyroxene piezometry. For the upper mantle, differential stress estimates are 10-20 MPa. These results indicate that the strength of the lower crust and the upper mantle are very similar. Our data do not fit with the general models of lithospheric strength and may have important implications for the rheological structure of the lithosphere in transtensional plate margins and for geodynamic models of the region.

  11. Baja loggerhead

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Pacific Coast of the Baja California Peninsula (BCP), Mexico, is a hotspot for foraging loggerhead turtles Caretta caretta originating from nesting beaches in...

  12. Molecular epidemiology of Mycobacterium tuberculosis in Baja California, Mexico: A result of human migration?

    Science.gov (United States)

    Flores-López, Carlos A; Zenteno-Cuevas, Roberto; Laniado-Laborín, Rafael; Reynaud, Yann; García-Ortiz, Rosa Alejandra; González-Y-Merchand, Jorge A; Rivera, Sandra; Vázquez-Chacón, Carlos A; Vaughan, Gilberto; Martínez-Guarneros, José Armando; Victoria-Cota, Nelva Lorena; Cruz-Rivera, Mayra; Rastogi, Nalin; Muñiz-Salazar, Raquel

    2017-11-01

    The State of Baja California (BC) exhibits the highest incidence and prevalence rates of tuberculosis (TB), and multidrug-resistant TB (MDR-TB) in Mexico. However information about the circulation of M. tuberculosis lineages in BC and Mexico as a whole is limited. Here, we describe the genetic relationship and genetic diversity among M. tuberculosis clinical isolates (n=140) collected in BC between October 2009 and April 2011 with other regions of Mexico, the United States, and Latin America. All specimens were genotyped based on 24 mycobacterial interspersed repetitive units (MIRU)-variable number of tandem repeats (VNTR) loci. Population structure and minimum spanning tree (MST) analyses were used to assess the genetic diversity and distribution of BC isolates in comparison to USA and South America strains. Among the nine lineages observed, LAM, Haarlem and S were the most frequent identified in BC. Population structure analysis clustered most BC isolates (41%) into three distinctive groups that included strains from San Diego and South America, whereas other BC strains (22%) clustered with other Mexican strains. A subset of isolates (12%) seemed to be autochthonous of BC, while 25% were cosmopolitan and grouped into multiple clusters. It is highly likely that the TB genetic structure observed in BC is due to human migration. Additional studies are required to determine the mechanism involved in the phylogeographic distribution of M. tuberculosis in Mexico. Implementation of domestic molecular TB surveillance programs is required to better understand the molecular epidemiology of TB not only in the region but at the national level. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Movilidad de población y comportamiento reproductivo: El caso de Baja California

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    Gabriel Estrella Valenzuela

    1992-09-01

    Full Text Available Este trabajo tiene como objetivo central evaluar el impacto indirecto que genera la inmigración hacia Baja California a través del comportamiento reproductivo de la población que, al migrar, ha cambiado su residencia habitual a la entidad. Para lograr ese objetivo, se analiza la información de las Encuestas Demográficas de Baja California de 1986 y 1990 con el modelo de los determinantes próximos de la fecundidad. Los resultados de dicho análisis muestran, por una parte, que los patrones reproductivos de la población migrante y no-migrante son c1aramentediferenciados (tanto en términos de fecundidad ilegítima como de formación de uniones, de sus prácticas anticonceptivas y de lactancia postparto, y que de ello se deriva un diferencial de fecundidad que resulta ser 17.5% superior para la población migrante en 1990. Por otra parte, los resultados también permiten estimar que, por cada tres nuevos inmigrantes que por año recibe la entidad, la inmigración acumulada aporta dos nuevos residentes con los nacimientos generados por las mujeres migrantes. Dada la magnitud que adquieren esos procesos (i.e. 59 mil nuevos habitantes por año ~ total, se concluye sugiriendo líneas generales de acción que permitan adecuar la política de población a las condiciones específicas de Baja California

  14. Atención prenatal y mortalidad materna hospitalaria en Tijuana, Baja California

    OpenAIRE

    Gonzaga-Soriano, María Rode; Zonana-Nacach, Abraham; Anzaldo-Campos, María Cecilia; Olazarán-Gutiérrez, Asbeidi

    2014-01-01

    Objetivo. Describir la atención médica prenatal recibida en mujeres con mortalidad materna hospitalaria en el IMSS durante 2005-2012 en Tijuana, Baja California, México. Material y métodos. La información se obtuvo de los archivos de los Comités de Mortalidad Materna y revisión del expediente. Resultados. Hubo 44 muertes maternas (MM). Treinta (68%) asistieron a atención prenatal (AP), el promedio de citas fue de 3.8 y 18 (41%) tuvieron una AP adecuada (≥ 5 citas). Seis (14%) mujeres no sabía...

  15. Mass media, espacio y tiempo en Todos Santos, Baja California Sur

    OpenAIRE

    Rossana Almada

    2001-01-01

    El artículo que aquí se sintetiza es un primer acercamiento, desde la perspectiva de autores entre los que destaca Manuel Castells, a un proyecto mayor que pretende analizar e interpretar el proceso de transformaciones que ha venido sufriendo el pueblo de Todos Santos, Baja California Sur BCS, debido a la llegada de dos contingentes de inmigrantes: el primero, rocedente de Estados Unidos y Canadá, llegó a comprar las casas del centro del pueblo; algunos con la intención de quedarse e inst...

  16. Competitividad empresarial de las pequeñas y medianas empresas manufactureras de Baja California

    OpenAIRE

    Ibarra Cisneros, Manuel Alejandro; González Torres, Lourdes Alicia; Demuner Flores, María del Rosario

    2017-01-01

    Resumen: El objetivo de esta investigación es determinar el nivel de competitividad empresarial de las pymes manufactureras de Baja California e identificar las áreas que dentro de ellas, influyen en dicha competitividad. La metodología es de carácter descriptivo, correlacional y de corte transversal; se desarrolló el modelo de competitividad sistémica a escala micro y se aplicó un instrumento de medición de 64 preguntas a 195 empresas del estado; además, se hizo uso de regresiones lineales m...

  17. Evolution of the east-central San Jose del Cabo basin, Baja California Sur, Mexico

    Science.gov (United States)

    McTeague, M. S.; Umhoefer, P. J.; Schwennicke, T.; Ingle, J. C.; Cortes Martinez, M.

    2006-12-01

    The San Jose del Cabo basin at the southern tip of the Baja California peninsula records the early tectonic evolution of the west side of the Gulf of California. This study focused on the east central margin of the basin. The basal La Calera Formation unconformably overlies Cretaceous granite and consists of conglomerate, pebbly sandstone and conglomerate, and sandstone deposited in alluvial fans and fan-deltas. Deposition of the La Calera Formation was from ca. 9-14 Ma. The lower member of the Trinidad Formation was deposited beginning ca. 9-13 Ma and consists of sandstone, mudstone, and shelly mudstone deposited in nearshore and estuarine environments. These age estimates are based on sedimentation rates and foraminifera and coccoliths from the NN 11A nannozone (7.4 8.6 Ma, GTS 2004). The middle member of the Trinidad Formation consists of deeper water mudstones deposited by turbidity currents and suspension settling in a shelf to slope and conglomerates deposited by submarine debris flows on the shelf. The basin began earlier than previously thought. The oldest marine rocks are ca.9-13 Ma, while sedimentation on the east side began at ca. 9-14 Ma, synchronous with estimates of initiation of offset on the San Jose del Cabo fault. The Zapote fault is a down-to-the-east normal and sinistral-oblique fault that exposes a wedge of granite and older strata in the footwall to the west. The fault was active during sedimentation in the late Miocene and possibly later. The fault divides the study area into an eastern hanging wall subbasin and western footwall subbasin. The eastern subbasin formed an embayment in the eastern margin of the Cabo basin. A regional flooding surface (ca. 8 Ma) can be correlated across the fault that marks a major marine incursion. Depositional systems evolved rapidly from coarse-grained terrestrial systems to fine-grained marine and estuarine systems. The Cabo basin provides an excellent analogue for comparison with offshore basins, which are

  18. Macroalgas submareales de la bahía de Todos Santos, Baja California, México Submareal macroalgae of the Todos Santos Bay, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Raúl Aguilar-Rosas

    2010-12-01

    Full Text Available Con el fin de identificar y caracterizar la composición de especies de la zona submareal de la bahía de Todos Santos, Baja California, México; se realizaron muestreos de macroalgas marinas bentónicas en 7 sitios durante 1995-2000. Como resultado de 25 buceos Scuba entre 3 y 33 m de profundidad se encontraron 150 especies de macroalgas para el área de estudio; 10 son Chlorophyta, 26 Phaeophyta y 114 Rhodophyta. Del total, 47 son registros nuevos para el área de estudio y 2 de éstos, Faucheocolax attenuata Setchell y Minium parvum R.L. Moe, son nuevos para la flora marina del Pacífico de México. Se incluye una revisión de las investigaciones en las que se han considerado las macroalgas presentes en la bahía de Todos Santos y una discusión sobre la composición de las especies encontradas, su distribución vertical y reproducción, así como sobre las especies epífitas y parásitas del área.In order to identify and characterize the species composition of the subtidal zone of the Todos Santos Bay, Baja California, Mexico, benthic marine macroalgae were sampled at 7 sites from 1995 to 2000. As a result of 25 scuba at derds for the study area, of which Faucheocolax attenuata Setchell and R.L Moe Minium parvum are new to the marine flora of Pacific Mexico. We include a research that consider the macroalpths between 3 and 33 m we found a total of 150 species of macroalgae for the study area, of which 10 are Chlorophyta, 26 Phaeophyta and 114 Rhodophyta; 47 species represent new recogae in the Todos Santos Bay and a discussion on the composition of species found, its vertical distribution and reproduction, particularly the species epiphytes and parasites present in the study area.

  19. New and noteworthy waterfowl records at artificial wetlands from Baja California Sur, Mexico Registros nuevos y sobresalientes de anátidos en humedales artificiales de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Roberto Carmona

    2011-06-01

    Full Text Available We present 9 recent records of rare waterfowls in Baja California Sur, all of them in artificial wetlands: 3 freshwater sites and 1 concentration area for a saltworks. We present the first records of the Ross's Goose in the state. The remaining 8 species are: Black-bellied Whistling-Duck (breeding, Fulvous Whistling-Duck, Greater White-fronted Goose, Snow Goose, Cackling Goose, Tundra Swan, Mallard and Hooded Merganser. To this list we added an historical compilation of the records of these species in artificial sites of the state. The artificial wetlands are no replacement for their natural counterparts, they are nevertheless an important part of the region's landscape mosaic. As the records of the present work exemplify, this man-made habitat increases the regional species richness, and should be considered as important areas that need to be protected.Presentamos registros recientes de 9 especies de anátidos raros en Baja California Sur, todos ellos realizados en humedales creados por el hombre: 3 sitios dulceacuícolas y 1 área de concentración para la producción de sal. Se incluyen los primeros registros del ganso de Ross (Chen rossii para el estado. Las 8 especies restantes son: Dendrocygna autumnalis (anidación, D. bicolor, Anser albifrons, Chen caerulesens, Branta hutchinsii, Cygnus columbianus, Anas platyrhynchos y Lophodytes cucullatus. A la lista, agregamos una recopilación histórica de los registros de estas especies en humedales artificiales del estado. Aunque estos sitios no deben sustituir a sus contrapartes naturales, actualmente forman parte del mosaico paisajístico que ofrece la región; adicionalmente, incrementan la riqueza de especies de la región, por lo que es necesario brindarles protección.

  20. Phytoplankton on the western coasts of Baja California in two different seasons in 1998

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    David U. Hernández-Becerril

    2007-12-01

    Full Text Available Phytoplankton was studied in two different seasons of 1998 (March-April and December, during two cruises along the western coasts of Baja California, in three zones. Two different protocols for obtaining and studying phytoplankton were followed. In the March-April season, phytoplankton had relatively low species richness and was dominated in cell density (up to 93% by coccolithophorids (mainly Emiliania huxleyi, together with nanoplanktonic centric and pennate diatoms, with abundances ranging from 5.4 103 to 1.2 105 cells L-1. In December, phytoplankton had higher species richness and was represented by larger, chain-forming diatom species, such as Pseudonitzschia delicatissima and P. pungens, which were widespread and numerically significant. There was a relative scarcity of coccolithophorids and thecate dinoflagellates, and densities were between 7 102 and 1.4 106 cells L-1. Hydrographic and oceanographic conditions in March-April were influenced by the occurrence of El Niño and the phytoplankton structure was found to be modified accordingly, with nanoplanktonic coccolithophorids and diatoms being significant contributors to the total abundance. In contrast, post-upwelling conditions might have favoured relatively high densities of Pseudonitzschia and other diatoms in December, 1998. Coccolithophorids have not been previously regarded as important contributors to the phytoplankton abundances in Baja California.

  1. LAS MUJERES EN LA MIGRACIÓN INTERNA Y EL EMPLEO INFORMAL EN BAJA CALIFORNIA SUR, MÉXICO

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    ALBA E. GÁMEZ

    2010-01-01

    Full Text Available Este artículo analiza las características del fenómeno migratorio en Baja California Sur, en la costa norte del Pacífico mexicano, donde el turismo y la agricultura de exportación son dos sectores atractores de población. Esto ha estimulado una tasa de crecimiento demográfico promedio de 10% en la última década en regiones como Los Cabos, de las que se alimentan los sectores formal e informal. El propósito de este artículo es contribuir a la comprensión de la participación de las mujeres migrantes en el mercado laboral informal.

  2. Challenges and opportunities for implementing sustainable energy strategies in coastal communities of Baja California Sur, Mexico

    Science.gov (United States)

    Etcheverry, Jose R.

    This dissertation explores the potential of renewable energy and efficiency strategies to solve the energy challenges faced by the people living in the biosphere reserve of El Vizcaino, which is located in the North Pacific region of the Mexican state of Baja California Sur. This research setting provides a practical analytical milieu to understand better the multiple problems faced by practitioners and agencies trying to implement sustainable energy solutions in Mexico. The thesis starts with a literature review (chapter two) that examines accumulated international experience regarding the development of renewable energy projects as a prelude to identifying the most salient implementation barriers impeding this type of initiatives. Two particularly salient findings from the literature review include the importance of considering gender issues in energy analysis and the value of using participatory research methods. These findings informed fieldwork design and the analytical framework of the dissertation. Chapter three surveys electricity generation as well as residential and commercial electricity use in nine coastal communities located in El Vizcaino. Chapter three summarizes the fieldwork methodology used, which relies on a mix of qualitative and quantitative research methods that aim at enabling a gender-disaggregated analysis to describe more accurately local energy uses, needs, and barriers. Chapter four describes the current plans of the state government, which are focused in expanding one of the state's diesel-powered electricity grids to El Vizcaino. The Chapter also examines the potential for replacing diesel generators with a combination of renewable energy systems and efficiency measures in the coastal communities sampled. Chapter five analyzes strategies to enable the implementation of sustainable energy approaches in El Vizcaino. Chapter five highlights several international examples that could be useful to inform organizational changes at the federal

  3. Hazardous waste shipping in the northern border of Mexico: The situation of Baja California

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    Ramón A. Castillo Ponce

    2013-01-01

    Full Text Available In this document we evaluate the determinants of shipments of hazardous waste to the US. We consider a sample of firms operating in the state of Baja California for the 2008–2010 sample period. The analysis consists on the estimation of two econometric specifications. The first refers to a truncated model in the spirit of Tobit. The second is a probabilistic model. The results of the Tobit model suggest that size, location and origin of the firm influence the amount of shipments. In particular, shipments are positively associated with larger firms; those located in the municipality of Tijuana and those whose origin is foreign. The probabilistic model finds that a depreciation of the Mexican peso contributes to an increase in the likelihood of sending a shipment. This may be the result of an improvement in the border economic environment due to the depreciation of the currency.

  4. Restricciones de liquidez en microempresas y la importancia del financiamiento informal en Baja California

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    Martín Ramírez-Urquidy

    2009-01-01

    Full Text Available La estructura industrial de México incorpora una proporción significativa de agentes que emprenden negocios a escalas reducidas y en un esquema de informalidad. Esta condición los aleja de los mercados formales de crédito, por lo que enfrentan una restricción permanente de liquidez. Este artículo prueba la hipótesis de que existen microempresas (MES no restringidas a pesar de esta limitación formal. Los resultados ilustran esta posibilidad al encontrar, en una muestra de mes del estado de Baja California, lo que implica el acceso a financiamiento externo y la importancia de las fuentes informales.

  5. Hombres violentados en la pareja. Jóvenes de Baja California, México

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    Humberto González Galbán

    2014-01-01

    Full Text Available El objetivo del presente trabajo es contribuir a la creación de conocimiento y conciencia sobre la violencia de pareja de la mujer contra el hombre, ello para el caso es - pec í ¿co de los jóvenes heterosexuales de Baja California. Para tal ¿n se presentan algunos antecedentes de estudio realizados en el contexto internacional y nacional, y se analiza dicha problemática en el escenario bajacaliforniano, que se sustenta en elementos empí - ricos disponibles sobre la entidad. Entre los hallazgos de mayor interés se destaca la alta incidencia de violencia contra los jóvenes en esta parte de la frontera norte de México, características sociodemográ¿cas y sociopsicológicas asociadas a la referida situación y el surgimiento de nuevas interrogantes sobre esta transcendente temática.

  6. Plague Law or Martial Law?: Sinaloa and Baja California, 1902-1903

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    Ana María Carrillo

    2005-04-01

    Full Text Available This paper analyzes the social importance of the plague epidemic that caught Sinaloa and Baja California,  Mexico, in 1902 and 1903. It describes the health campaign  that was organized, the first one —in Mexico— based on the recent scientific fields of microbiology, immunology and tropical medicine.  It was also the first one in which a state turned control of sanitary activities in to the federal government. The author shows that in this campaign, health personnel  and political authorities used persuasion and, above all, compulsion, and describes how the population resisted the health measures. She analyzes the contradictions between the different actors of the campaign, explains the causes of its success and points  out  that the 1902-1903 campaign against plague became a model for further health campaigns in Mexico.

  7. [Prenatal care and hospital maternal mortality in Tijuana, Baja California, Mexico].

    Science.gov (United States)

    Gonzaga-Soriano, María Rode; Zonana-Nacach, Abraham; Anzaldo-Campos, María Cecilia; Olazarán-Gutiérrez, Asbeidi

    2014-01-01

    To describe the prenatal care (PC) received in women with maternal hospital deaths from 2005 to 2011 in Tijuana, Baja California, Mexico. Were reviewed the medical chars and registrations of the maternal deaths by the local Committees of Maternal Mortality. There were 44 maternal hospital deaths. Thirty (68%) women assisted to PC appointments during pregnancy, the average number of PC visits was 3.8 and 18 (41%) had an adequate PC (≥ 5 visits). Six (14%) women didn't know they were pregnant; 19 (43%), 21 (48%) y 4 (9%) maternal deaths were due to direct, indirect obstetric cause or non-obstetric causes. Eighteen (18%), 2 (4 %) and 34 (77%) of the maternal deaths occurred during pregnancy, delivery or puerperium. It is necessary pregnancy women have an early, periodic and systematic PC to identify opportunely risk factors associated with pregnancy complications.

  8. Metal concentrations in demersal fish species from Santa Maria Bay, Baja California Sur, Mexico (Pacific coast).

    Science.gov (United States)

    Jonathan, M P; Aurioles-Gamboa, David; Villegas, Lorena Elizabeth Campos; Bohórquez-Herrera, Jimena; Hernández-Camacho, Claudia J; Sujitha, S B

    2015-10-15

    Concentrations of 11 trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, As, Hg) in 40 fish species from Santa Maria Bay, Baja California Sur, Mexico, the strategically important area for marine mammals and organisms were analyzed. Based on their concentrations the ranking of metals Fe>Zn>Ni>Cr>Mn>Pb>Cu>Co>As>Cd>Hg suggests that organism size, metabolism and feeding habits are correlated with metal concentrations. Local geological formations affect the concentrations of different metals in the aquatic environment and are subsequently transferred to fishes. The correlation analysis suggests that metabolism and nurturing habits impact the concentration of metals. Concentrations of Fe and Mn appear to be influenced by scavenging and absorption processes, which vary by species. The considerable variability in the metal concentrations obtained in different species underscores the importance of regular monitoring. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Management by results in Mexico, 2013-2014. Some effects in Baja California

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    José María Ramos García

    2016-07-01

    Full Text Available This paper examines the results-based management (RBM proposal promoted by the Mexican federal government and how this proposal has been applied. This article presents the theory of management according to its results and its effects on competitiveness and well-being. This article analyzes the conceptual elements of the model and the manners in which this model has been instituted both conceptually and operationally in Brazil, Mexico, and the Mexican state of Baja California. Principal findings include the need to strengthen institutional capacities for RBM to enhance competitiveness and well-being at the government level, internalize a vision of strategic change, and prioritize cultural change to generate efficient transparency, accountability and anti-corruption controls by a transversal focus based on the elements of management.

  10. Cyanobacterial diversity in extreme environments in Baja California, Mexico: a polyphasic study.

    Science.gov (United States)

    López-Cortés, A; García-Pichel, F; Nübel, U; Vázquez-Juárez, R

    2001-12-01

    Cyanobacterial diversity from two geographical areas of Baja California Sur, Mexico, were studied: Bahia Concepcion, and Ensenada de Aripez. The sites included hypersaline ecosystems, sea bottom, hydrothermal springs, and a shrimp farm. In this report we describe four new morphotypes, two are marine epilithic from Bahia Concepcion, Dermocarpa sp. and Hyella sp. The third, Geitlerinema sp., occurs in thermal springs and in shrimp ponds, and the fourth, Tychonema sp., is from a shrimp pond. The partial sequences of the 16S rRNA genes and the phylogenetic relationship of four cyanobacterial strains (Synechococcus cf. elongatus, Leptolyngbya cf. thermalis, Leptolyngbya sp., and Geitlerinema sp.) are also presented. Polyphasic studies that include the combination of light microscopy, cultures and the comparative analysis of 16S rRNA gene sequences provide the most powerful approach currently available to establish the diversity of these oxygenic photosynthetic microorganisms in culture and in nature.

  11. Implementing relational marketing in a coffee selling company in Baja California

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    Isaac Cruz Estrada

    2018-01-01

    Full Text Available The aim of this investigation is to propose a relationship marketing process in a coffee selling company in Baja California as a case study. First, relationship marketing is conceptualized and its contribution to the creation of value in organizations is analyzed; moreover, empirical studies from various authors, who point out the influence of this process on customer satisfaction, are included. 149 surveys were conducted in order to obtain the correlation between the guarantee to offer a product or service and value generation by delivering tangible and intangible elements for customer satisfaction. This proposal belongs to the company where the research was carried out; it can be adapted to organizations which offer a service and are in the situation studied.

  12. Possibilities of Mexican SMEs insertion in the aerospace industry value chain, the Baja California case

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    Juana Hernández Chavarria

    2018-01-01

    Full Text Available The goal of this article is to analyze the aerospace industry in Baja California, Mexico. The methodology is based on the application of an electronic questionnaire and face-to-face in depth interviews. Our results shows that the insertion of companies has been conditioned by several factors: the basic certification is only the first step; the real challenge is to find niches of opportunity and bargaining power to achieve a productive contract, which demands entrepreneurial, legal and economic skills. This analysis is a pioneer in the study of Mexican companies participating in this emerging sector. The main limitations were the access to the companies’ information and the rejection to participate in the study. The main finding is there are very few Mexican suppliers integrated to the global value aerospace chain but if the trend of growth is maintained, it may had greater integration in the near future, and possibly a greater economic spill and technology transfer.

  13. Characteristics regarding the consumer of giant squid from Baja California Sur, Mexico

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    Liliana Enriqueta Montaño Méndez

    2015-01-01

    Full Text Available The catch of the giant squid (Dosidicus gigas, represents de second fishing activity most important in volume in Baja California Sur, Mexico; is an essential specie not only at the state level but at the pacific and even the national level. Mexico occupies in the world the eight level in the production of squid, but the national consumption, even though the low price of the product and the high nutritional level, is approximately 0.53 kg per year, very low compared to countries like Japan, Korea and Spain (average consumption per capita is of 3.5 kg . In this context, the objective of this article is to caracterize the sudcalifornia consumer preference; determine the buying habits and the consumption; and also to establish the market areas of the squid in Baja California Sur, which allows the introduction of actions for its commercialization, in order to strengthen the market of this product and its general activity. This is why in 2012 a questioner of 1066 consumers was distribute around the five counties of the state, according to the population density. The results indicate that the principal motive why there is not consumption is the difficulty to find places where to buy it, together with the problems of cooking it. Also, it can be seen the high level of ignorance the consumer has regarding the nutritional level this food has. For this reason, future strategies for the commercialization must be focus on better distribution and new form of presenting this product which facilitates its preparation and consumption, and at the same time create campaign which increase awareness of the nutrition level this product has.

  14. Predicting Pinus monophylla forest cover in the Baja California Desert by remote sensing

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    Jonathan G. Escobar-Flores

    2018-04-01

    Full Text Available The Californian single-leaf pinyon (Pinus monophylla var. californiarum, a subspecies of the single-leaf pinyon (the world’s only one-needled pine, inhabits semi-arid zones of the Mojave Desert (southern Nevada and southeastern California, US and also of northern Baja California (Mexico. This tree is distributed as a relict subspecies, at elevations of between 1,010 and 1,631 m in the geographically isolated arid Sierra La Asamblea, an area characterized by mean annual precipitation levels of between 184 and 288 mm. The aim of this research was (i to estimate the distribution of P. monophylla var. californiarum in Sierra La Asamblea by using Sentinel-2 images, and (ii to test and describe the relationship between the distribution of P. monophylla and five topographic and 18 climate variables. We hypothesized that (i Sentinel-2 images can be used to predict the P. monophylla distribution in the study site due to the finer resolution (×3 and greater number of bands (×2 relative to Landsat-8 data, which is publically available free of charge and has been demonstrated to be useful for estimating forest cover, and (ii the topographical variables aspect, ruggedness and slope are particularly important because they represent important microhabitat factors that can determine the sites where conifers can become established and persist. An atmospherically corrected a 12-bit Sentinel-2A MSI image with 10 spectral bands in the visible, near infrared, and short-wave infrared light region was used in combination with the normalized differential vegetation index (NDVI. Supervised classification of this image was carried out using a backpropagation-type artificial neural network algorithm. Stepwise multiple linear binominal logistical regression and Random Forest classification including cross validation were used to model the associations between presence/absence of P. monophylla and the five topographical and 18 climate variables. Using supervised

  15. Latitudinal changes of euphausiid assemblages related to the morphological variability of the sound scattering layer along Baja California, October 1994

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    J. Gómez-Gutiérrez

    1999-03-01

    Full Text Available Latitudinal changes in the euphausiid assemblages were compared to the morphological structure (size and compactness of the sound scattering layer (SSL during ten 24-h surveys made in October 1994 along the west coast of Baja California, México. During October, upwelling was found in the northern area from Punta Eugenia (28°N to Ensenada (30°N dominated by temperate species from the California Current System. In the southern sector of the peninsula, a northward movement of tropical waters transports a tropical zooplankton assemblage near Bahia Magdalena (24°N. The aggregation and the dispersion of the whole SSL (plankton and nekton were investigated using a single beam vertical echosounder, Simrad EY-200, working at 200 kHz and the Hydro Acoustic Data Acquisition System (HADAS that estimates patch variables of density and compactness. The size and shape of the SSL were obtained from the echogram visualization. The euphausiid species composition was obtained using an Isaacs-Kidd midwater trawl, bongo nets, and opening-closing nets. At Ensenada and Punta Eugenia, an area inhabited by a temperate euphausiid assemblage, large and dense SSLs were recorded over the continental shelf (mean sizes were 10-km and 7-km long with mean compactness of 15% and 19%. These regions were dominated by the neritic species Nyctiphanes simplex and the temperate species Nematoscelis difficilis, Euphausia pacifica, and Thysanoessa spinifera. In the southern area, a tropical euphausiid assemblage, dominated by Euphausia eximia, E tenera, and E. distinguenda, inhabits smaller and dispersed SSLs (mean size 5-km long and 11% compactness located in the offshore area. The euphausiid biomass of the most abundant species indicated, N. simplex and N. difficilis, had their highest standing stock in the north (393 and 643 mg C 1000 m-3, with E. eximia in the southern area (186 mg C 1000 m-3. Euphausiid assemblage development in different biological environments, is evidenced

  16. PATHOGENIC LEPTOSPIRA SEROVARS IN FREE-LIVING SEA LIONS IN THE GULF OF CALIFORNIA AND ALONG THE BAJA CALIFORNIA COAST OF MEXICO.

    Science.gov (United States)

    Avalos-Téllez, Rosalía; Carrillo-Casas, Erika M; Atilano-López, Daniel; Godínez-Reyes, Carlos R; Díaz-Aparicio, Efrén; Ramírez-Delgado, David; Ramírez-Echenique, María F; Leyva-Leyva, Margarita; Suzán, Gerardo; Suárez-Güemes, Francisco

    2016-04-28

    The California sea lion ( Zalophus californianus ), a permanent inhabitant of the Gulf of California in Mexico, is susceptible to pathogenic Leptospira spp. infection, which can result in hepatic and renal damage and may lead to renal failure and death. During summer 2013, we used the microscopic agglutination test (MAT) to investigate the prevalence of anti-Leptospira antibodies in blood of clinically healthy sea lion pups from seven rookery islands on the Pacific Coast of Baja California (Pacific Ocean) and in the Gulf of California. We also used PCR to examine blood for Leptospira DNA. Isolation of Leptospira in liquid media was unsuccessful. We found higher antibody prevalence in sea lions from the rookery islands in the gulf than in those from the Pacific Coast. Antibodies against 11 serovars were identified in the Gulf of California population; the most frequent reactions were against serovars Bataviae (90%), Pyrogenes (86%), Wolffi (86%), Celledoni (71%), and Pomona (65%). In the Pacific Ocean population, MAT was positive against eight serovars, where Wolffi (88%), Pomona (75%), and Bataviae (70%) were the most frequent. Serum samples agglutinated with more than one Leptospira serovar. The maximum titer was 3,200. Each island had a different serology profile, and islands combined showed a distinct profile for each region. We detected pathogenic Leptospira DNA in 63% of blood samples, but we found no saprophytic Leptospira. Positive PCR results were obtained in blood samples with high and low MAT titers. Together, these two methods enhance the diagnosis and interpretation of sea lion leptospirosis. Our results may be related to human activities or the presence of other reservoirs with which sea lions interact, and they may also be related to sea lion stranding.

  17. A possible connection between post-subduction arc magmatism and adakite-NEB rock association in Baja California, Mexico

    Science.gov (United States)

    Castillo, P. R.

    2007-05-01

    Late Miocene to Recent arc-related magmatism occurs in Baja California, Mexico despite the cessation of plate subduction along its western margin at ~12.5 Ma. It includes calcalkaline and K-rich andesites, tholeiitic basalts and basaltic andesites, alkalic basalts similar to many ocean island basalts (OIB), magnesian and basaltic andesites with adakitic affinity (bajaiites), adakites, and Nb-enriched basalts (NEB). A popular model for the close spatial and temporal association of adakite (plus bajaiite) and NEB in Baja California is these are due to melting of the subducted Farallon/Cocos plate, which in turn is caused by the influx of hot asthenospheric mantle through a window created in the subducted slab directly beneath the Baja California peninsula [e.g., Benoit, M. et. al. (2002) J. Geol. 110, 627-648; Calmus, T. et al. (2003) Lithos 66, 77-105]. Here I propose an alternative model for the cause of post-subduction magmatism in Baja California in particular and origin of adakite-NEB rock association in general. The complicated tectonic configuration of the subducting Farallon/Cocos plate and westward motion of the North American continent caused western Mexico to override the hot, upwelling Pacific mantle that was decoupled from the spreading centers abandoned west of Baja California. The upwelling asthenosphere is best manifested east of the peninsula, beneath the Gulf of California, and is most probably due to a tear or window in the subducted slab there. The upwelling asthenosphere is compositionally heterogeneous and sends materials westward into the mantle wedge beneath the peninsula. These materials provide sources for post-subduction tholeiitic and alkalic magmas. Portions of tholeiitic magmas directly erupted at the surface produce tholeiitic lavas, but some get ponded beneath the crust. Re-melting and/or high-pressure fractional crystallization of the ponded tholeiitic magmas generate adakitic rocks. Alkalic magmas directly erupted at the surface

  18. The vascular flora and floristic relationships of the Sierra de La Giganta in Baja California Sur, Mexico La flora vascular y las relaciones florísticas de la sierra de La Giganta de Baja California Sur, México

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    José Luis León de la Luz

    2008-06-01

    Full Text Available The Sierra de La Giganta is a semi-arid region in the southern part of the Baja California peninsula of Mexico. Traditionally, this area has been excluded as a sector of the Sonoran Desert and has been more often lumped with the dry-tropical Cape Region of southern Baja California peninsula, but this classical concept of the vegetation has not previously been analyzed using formal documentation. In the middle of the last century, Annetta Carter, a botanist from the University of California, began explorations in the Sierra de La Giganta that lasted 24 years, she collected 1 550 specimens and described several new species from this area, but she never published an integrated study of the flora. Our objectives, having developed extensive collections in the same area over the past years, are to provide a comprehensive species list and description of the vegetation of this mountain range. We found a flora of 729 taxa, poorly represented in tree life-forms (3.1%, a moderate level (4.4% of endemism, and the dominance of plants in the sampling plots is composed mainly for legume trees and shrubs. Additionally, using a biogeographical approach, we compare our list with other known lists of plants from 5 areas, 3 in the Cape Region, 1 in the Sonoran Desert, and other in the thornscrub area of NW Mexico. We conclude that the La Giganta flora has a mixed composition, primarily made up of plants shared with the lowlands of the southern Cape Region, but also share an important proportion of the flora with the desert mountains of the central peninsula and some with the Sonoran desertscrub of mainland Mexico. Consequently we support that the La Giganta flora is part of a floristic continuum along the volcanic mountains of the southern peninsula that eventually could be considered a new eco-region in the same peninsular land.La sierra de La Giganta se localiza en el estado de Baja California Sur, México, en una región semi-árida. Tradicionalmente, esta

  19. Food webs including parasites, biomass, body sizes, and life stages for three California/Baja California estuaries

    Science.gov (United States)

    Hechinger, Ryan F.; Lafferty, Kevin D.; McLaughlin, John P.; Fredensborg, Brian L.; Huspeni, Todd C.; Lorda, Julio; Sandhu, Parwant K.; Shaw, Jenny C.; Torchin, Mark E.; Whitney, Kathleen L.; Kuris, Armand M.

    2001-01-01

    This data set presents food webs for three North American Pacific coast estuaries and a “Metaweb” composed of the species/stages compiled from all three estuaries. The webs have four noteworthy attributes: (1) parasites (infectious agents), (2) body-size information, (3) biomass information, and (4) ontogenetic stages of many animals with complex life cycles. The estuaries are Carpinteria Salt Marsh, California (CSM); Estero de Punta Banda, Baja California (EPB); and Bahía Falsa in Bahía San Quintín, Baja California (BSQ). Most data on species assemblages and parasitism were gathered via consistent sampling that acquired body size and biomass information for plants and animals larger than ∼1 mm, and for many infectious agents (mostly metazoan parasites, but also some microbes). We augmented this with information from additional published sources and by sampling unrepresented groups (e.g., plankton). We estimated free-living consumer–resource links primarily by extending a previously published version of the CSM web (which the current CSM web supplants) and determined most parasite consumer–resource links from direct observation. We recognize 21 possible link types including four general interactions: predators consuming prey, parasites consuming hosts, predators consuming parasites, and parasites consuming parasites. While generally resolved to the species level, we report stage-specific nodes for many animals with complex life cycles. We include additional biological information for each node, such as taxonomy, lifestyle (free-living, infectious, commensal, mutualist), mobility, and residency. The Metaweb includes 500 nodes, 314 species, and 11 270 links projected to be present given appropriate species' co-occurrences. Of these, 9247 links were present in one or more of the estuarine webs. The remaining 2023 links were not present in the estuaries but are included here because they may occur in other places or times. Initial analyses have examined

  20. Geochemistry of Dissolved Trace Metals in the Waters of Bahia Magdalena, Baja California Sur, Pacific Coast, Mexico

    Science.gov (United States)

    Suresh Babu, S.

    2016-12-01

    Forty two samples were acquired from the surface and bottom water profiles along 5 transects spread over Bahia Magdalena lagoon, Baja California Sur to assess the behavior of trace metals in a high influenced upwelling region on the Pacific coast. To elaborate the fate of metals, also the physico-chemical parameters (pH, temperature, salinity, conductivity, dissolved oxygen). Determination of the concentrations of trace metals (Fe, Mn, Cr, Cu, Co, Pb, Ni, Zn, Cd As, Hg) were measured using Atomic absorption spectrometry. The results demonstrated high values of As, Ni and Co which is attributed to the local geology and phosphate deposits. Low values of Fe and Mn are attested to the oxic conditions of the lagoon which are responsible for the oxidation of Fe and Mn. The region witnesses raised temperatures (28.92ºC) and salinities of 35.2 PSU for its arid climatic conditions and high rates of evaporation. In general, the region presented minor quantities of dissolved trace metals due to dispersion and high intense interaction with the open sea. The results were also compared with other studies to understand the enrichment pattern in this side of the pacific coast which experiences various geothermal activities and upwelling phenomenon.

  1. Subsidence of the Laguna Salada Basin, northeastern Baja California, Mexico, inferred from Milankovitch climatic changes

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, Juan; Martin-Barajas, Arturo [Departamento de Geologia, CICESE, Ensenada Baja California (Mexico); Herguera, Juan Carlos [Division de Oceanologia, CICESE, Ensenada Baja California (Mexico)

    2005-01-15

    Laguna Salada in northern Baja California, Mexico, is an active half-graben product of the trans-tensional tectonics of the Gulf of California. It is sensitive to changes in sediment supply from the Colorado River basin. We present a time series analysis of the upper 980 m of a gamma-ray log from a borehole drilled near the Laguna Salada fault. The power spectrum of the gammaray log resembles the spectrum of {delta}{sup 1}8{omicron} Pleistocene isotopic variations from ice cores and from the deep ocean, known to be strongly controlled by Milankovitch cycles. We correlate {delta}{sup 1}8{omicron} stages with silty and sandy intervals in the log. Downcore ages for the last 780 ky are constrained within {approx}10 kyr. We derive a simple time vs. depth calibration relation for the basin over this time interval. Estimated sedimentation rates at the drill site appear to be constant with a value of {approx}1.6 mm/yr. We propose that this subsidence rate is produced by the Laguna Salada fault. [Spanish] La cuenca de Laguna Salada en el norte de Baja California, Mexico, es un semigraben activo producto de la tectonica ranstensional del Golfo de California. Esta cuenca endorreica es sensible a cambios en sedimentacion por variaciones en el aporte e sedimentos de fuentes cercanas y distales transportados por arroyos de las sierras adyacentes y por el Rio Colorado. Esta cuenca es un sitio excepcional para explorar el uso de cambios climaticos ciclicos como herramienta de datacion y estimar tasas de sedimentacion y subsidencia en el area. Para demostrar esto se presenta un analisis de series de tiempo de un registro de rayos de gama de un pozo geotermico exploratorio perforado adyacente a la falla de Laguna Salada, la cual limita el margen oriental de la cuenca. Los resultados del analisis indican que el espectro de los primeros 980 m del registro de rayos gama tiene una alta coherencia con el espectro de registros isotopicos paleoclimaticos de {delta}{sup 1}8{omicron} del

  2. Comunidades de quitones (Mollusca: Polyplacophora de la Bahía de La Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Cedar I García Ríos

    2007-03-01

    Full Text Available A las ocho especies de poliplacóforos registradas en Bahía de la Paz, Baja California Sur, México, o cerca de ella, agregamos a Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata y Acanthochitona arragonites. El análisis de las comunidades estudiadas usando técnicas de ordenación sugiere que podría relacionarse la exposición al oleaje con la riqueza y la diversidad de especies. La comunidad recolectada en condiciones intermedias de exposición al oleaje presentó mayor número de especies y mayor diversidad de acuerdo con el índice de Shannon.Polyplacophoran communities (Mollusca: Polyplacophora at Bahía de La Paz, Baja California Sur, México. Eight species of polyplacophorans have been reported from La Bahía de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness and higher diversity (Shannon’s index. Rev. Biol. Trop. 55 (1: 177-182. Epub 2007 March. 31.

  3. Dinámica de los componentes demográficos en Baja California, durante el periodo 1985-1990

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    Gabriel Estrella Valenzuela

    1991-09-01

    Full Text Available En este trabajo se identifican los rangos predominantes en la dinámica de los componentes demográficos del estado de Baja California y sus municipios, durante el período 1985-1990. Para ello, se utilizan y combinan datos de estadísticas vitales, censales y de las Encuestas Demográficas de Baja California de 1986 y 1990. A partir del análisis de la mortalidad y la fecundidad, se logra determinar una tendencia de estabilidad en el componente natural de la dinámica demográfica del estado, con variaciones marginales a nivel municipal. En el rubro de crecimiento social, sin embargo, se observa un notable y claro incremento en la movilidad de la población que se sustenta en dos componentes: un incremento en la tasa de emigración desde el estado en su conjunto y una más elevada y consistente tendencia al incremento en las tasas de inmigración hacia Baja California, que revierte la tendencia decreciente del peso del crecimiento social en la entidad

  4. Demografía y economía de una capital estatal. Mexicali, Baja California

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    Gabriel Estrella Valenzuela

    1996-01-01

    Full Text Available This work has as a main objective, to identify, in a general way, the sectors of the economical activity in which the city of Mexicali presents a grade of specialization in respect to the state of Baja California in general. To accomplish such objective, in the first part, the general characteri'stics that have definedthe tendencies of demographic behavior in this zone of the country through the 20th century are marked, with the purpose of making evident the nexus that has existed between the modalities that have assumed the economical development of Mexicali, and the fluctuations that have been observed in the components of its population dynamic. The second part of this work is about the evaluation of the specialization of the economical structure of Mexicali, related to the capacity of creating jobs, and the kind of jobs that are created. In this case, tha analitic perspective ofthe "economical basis" is used, since it's important to show the role the border with the United States has played, in relation to the possibilities -past and present- of development in the economy of this area through the capacity of responding to the external demand of goods and services.

  5. en un área natural protegida en Baja California Sur

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    Elizabeth Olmos-Martínez

    2008-01-01

    Full Text Available Aquí se aborda el concepto de pobreza, enmarcado en el contexto de un área natural protegida (ANP, con la metodología propuesta por la Secretaría de Desarrollo Social (SEDESOL, cuya política pública maneja tres categorías para medirla: pobreza alimentaria, pobreza de capacidades y pobreza de patrimonio. El estudio de caso se efectuó en el ejido San Jorge (ESJ, ubicado dentro de la Reserva de la Biosfera Sierra La Laguna (REBISLA, en Baja California Sur. El análisis está basado en datos recolectados en entrevistas a los pobladores del lugar; se consideró el ingreso real diario per cápita, el cual indica si la persona es capaz de satisfacer las necesidades comprendidas en cada categoría, con un ingreso mínimo indispensable. Los resultados indican que la pobreza en la zona, de 2000 a 2004, no varió significativamente. Se concluyó que los habitantes del ESJ son pobres, según los propios parámetros de SEDESOL, y que su condición no ha mejorado, aunque viven en un ANP. Se analizan algunas alternativas que podrían ayudar a amortiguar este rezago.

  6. Spatial distribution of heavy metals in urban dust from Ensenada, Baja California, Mexico

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    José L. Cortés

    2017-01-01

    Full Text Available E n Ensenada, Baja California, los barcos y vehículos emiten partículas con metales pesados. Las partículas se transportan con el viento y se depositan en el suelo, donde se mezclan con él dando lugar a los polvos urbanos. Los metales pesados pueden afectar la salud de la población, por lo que se requiere un diagnóstico rápido para encontrar soluciones. El objetivo de este trabajo fue identificar las zonas con mayor contaminación en la ciudad. Se tomaron 86 muestras de polvo urbano sobre diferentes sustratos (suelo, cemento y asfalto. Los metales se analizaron mediante f luorescencia de rayos X. Las diferencias entre los sustratos se identificaron mediante un análisis de varianza. Por otra parte, se hizo un análisis para conocer la distribución espacial de los metales pesados, utilizando la interpolación con kriging ordinario. El asfalto contiene las mayores concentraciones de Cr, Ni, Pb y Zn; el cemento contiene mayores concentracions de Cu y V; y el suelo es el que más Rb contiene. El mapa que integra las clases de mayor concentración de metales indica que la zona suroeste, donde se localiza el puerto y pasa la carretera transpeninsular, es la más contaminada.

  7. Adaptive Thermal Comfort in Learning Spaces: A Study of the Cold Period in Ensenada, Baja California

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    Julio Rincón

    2017-12-01

    Full Text Available Environmental thermal conditions decisively influence people’s performance, comfort, well-being and mood. In closed spaces, where people spend 80% of their time, thermal perception is a phenomenon studied from a multidisciplinary methodological approach. In Mexico, thermal comfort has been studied in isolation in different cities in the country, specifically at sites with warm, temperate or semi-cold bioclimate. The thermal estimates presented in this paper are the result of a thermal comfort study carried out during the cold period in the city of Ensenada, Baja California, which has a dry temperate bioclimate. The study was carried out from January 30th to March 3rd 2017 and consisted of the application of a questionnaire and the simultaneous recording of temperature, relative humidity and wind speed. The questionnaire was designed based on the subjective assessment scale suggested in ISO 10551 and ANSI/ASHRAE 55, while the instruments for measuring and recording environmental variables were selected and used based on ISO 7726. A database with 983 observations was created, and the data were processed using the Averages Intervals Thermal Sensation method. The thermal comfort range estimated for indoor spaces was 16.8 °C to 23.8 °C, with an ideal neutral temperature of 20.3 °C. The percentage of satisfaction vote with these results was 91%.

  8. AUTOCHTHONOUS BIOFACIES IN THE PLIOCENE LORETO BASIN, BAJA CALIFORNIA SUR, MEXICO

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    MICHELE PIAZZA

    1998-07-01

    Full Text Available The present paper examines the molluscan and/or echinoid assemblages recovered from two lithostratigraphic units (Piedras Rodadas Sandstone and Arroyo de Arce Norte Sandstone outcropping in the Pliocene Loreto Basin, Baja California Sur, Mexico. Ten biofacies have been identified, i.e. Trachycardium procerum-Trachycardium senticosum Biofacies, Chione compta-Transennella modesta Biofacies, Laevicardium elenense-Chione kelletii Biofacies, Xenophora sp. 1-Strombus subgracilior Biofacies, Crassostrea californica osunai Biofacies, Myrakeena angelica Biofacies, Vermetid-Nodipecten Biofacies, Argopecten abietis abietis Biofacies, Aequipecten dallasi Biofacies and Encope Biofacies. The first four biofacies have been defined on the basis of statistical analyses (cluster analysis, MDS. The other six, which are monospecific or definitely low-diversity, were already identified during field work. The deduced paleoecological bearing of biofacies, largely relying upon the comparison to their closest modern counterparts, provides the basis for the paleoenvironmental reconstruction. The latter also considers sedimentological evidence and is framed within the tectonic and sedimentary context recently proposed by American workers. Biofacies point toward environments differing in terms of substrate texture, presence/absence of vegetal cover, energy level, variously distributed within the low tide mark-40 m bathymetric range. 

  9. Una exploración de las adaptaciones culturales prehistóricas en Baja California

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    Don Laylander

    1987-09-01

    Full Text Available Esta investigación profundiza acerca de cuáles cambios y cuándo ocurrieron en los estilos y las tecnologías prehistóricas tal como se ven reflejadas en la cultura material que se ha conservado. Al mismo tiempo analiza cómo fue que las sociedades lograron establecerse aquí y cómo fue que pudieron sostenerse y desarrollarse en este medio ecológico, o en su caso, por qué fracasaron en su intento. Con el fin de obtener información acerca de las adaptaciones culturales prehistóricas se recurre a la evidencia etnográfica y lingüística, y a la evidencia arqueológica. Otra fuente de información de las adaptaciones culturales de la Baja California es la analogía etnográfica general. Finalmente se hace un resumen de lo que fueron estas adaptaciones a modo de propuesta, con el fin de que la información resultante sea de utilidad para antropólogos y arqueólogos que partiendo del escrutinio de ésta contribuyan al avance del conocimiento de la prehistoria de esta región.

  10. Marine reserves help preserve genetic diversity after impacts derived from climate variability: Lessons from the pink abalone in Baja California

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    Adrián Munguía-Vega

    2015-07-01

    Full Text Available Genetic diversity is crucial for the adaptation of exploited species like the pink abalone (Haliotis corrugata, faced with threats from climate change, overfishing and impacts associated with aquaculture production. While marine reserves are commonly used to mitigate risks to marine populations, the duration, size, location and larval connectivity needed for a reserve to help conserve genetic resources is still poorly understood. Here, we examine the effects of fishing, reserves, and restocking on the genetic diversity of 10 populations from central Baja California, Mexico, and Southern California, USA. We demonstrate that each population shows characteristic genetic signatures according to recent management decisions. We found high allelic diversity, particularly rare alleles, a larger effective population size and a lack of a recent genetic bottleneck in pink abalones within a small (0.8 km2, recently established (5 years reserve in Baja California, compared to other fished sites after a climatic bottleneck. Higher diversity may result from the presence of older animals in the reserve. Due to its location, the reserve may also act as an important hub connecting distant populations via larval dispersal. In contrast, a population from California showed genetic isolation, loss of allelic diversity and high relatedness, consistent with the collapse of fisheries in the 1990s and their lack of recovery thereafter. In addition, a fished area in Baja California with a history of restocking for over a decade showed an increase in frequency of related individuals and high genetic differentiation from nearby sites that were consistent with the production of larvae from a few adults in the laboratory. A network of strategically placed small marine reserves that considers ocean circulation patterns could help to maintain genetic diversity and connectivity of exploited populations.

  11. Mass media, espacio y tiempo en Todos Santos, Baja California Sur

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    Rossana Almada

    2001-01-01

    Full Text Available El artículo que aquí se sintetiza es un primer acercamiento, desde la perspectiva de autores entre los que destaca Manuel Castells, a un proyecto mayor que pretende analizar e interpretar el proceso de transformaciones que ha venido sufriendo el pueblo de Todos Santos, Baja California Sur BCS, debido a la llegada de dos contingentes de inmigrantes: el primero, rocedente de Estados Unidos y Canadá, llegó a comprar las casas del centro del pueblo; algunos con la intención de quedarse e instalar negocios, principalmente de venta de Bienes Raíces, otros, para pasar allí la temporada otoño invierno; y el segundo, traído del interior del país, principalmente de Acayucan Veracruz y de Ocotepec Guerrero como jornaleros agrícolas por una compañía Sinaloense. Esta inmigración ha introducido a Todos Santos dentro de lo que Castells denomina como sociedad red, es decir, dentro de procesos sociales organizados, cada vez más, en torno a redes que constituyen las nuevas formas de organización social. En resumen, el presente trabajo aborda los efectos de la globalización en la transformación de un pueblo sudcaliforniano, a través de la llegada de los inmigrantes arriba mencionados y del uso de los medios de comunicación vía satélite.

  12. Turismo y Sustentabilidad en Pequeñas Localidades Localidades Costeras de Baja California Sur (BCS

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    Reyna Ibañez Pérez

    2014-01-01

    Full Text Available El fomento del turismo se realiza en sitios que, aunque pequeños, cuentan con atractivos naturales y culturales, tal es el caso de las zonas costeras. Tan solo en México, se estima que existen más de 1,100 comunidades que dependen directamente de dicha actividad, esta te ndencia se refleja, de igual manera, en pequeñas localidades costeras de Baja California Sur (BCS. En este sentido, el objetivo de este trabajo fue realizar un an álisis exploratorio que permitió detectar a las comunidades costeras de BCS, donde el turismo genera un aporte importante a su economía local, además , se buscó identificar la problemática general que éstas enfrentan. Para realizar dicho estudio se revisó literatura, se organizó información estadística y se elaboró un análisis Fortalezas, Oportunidades, Debilidades y Amenazas (FODA. Los resultad os apuntan a que, en BCS, existen más de 35 localidades ru rales vinculadas con dicha actividad que comparten como problemática la escasa in fraestructura y la carencia de medidas de control de la afluencia turística. La principal recomendación es desarrollar líneas de investigación que permitan aportar elementos para medir la sustentabilidad turística a nivel local y, co n base en ello, diseñar medidas para la adecuada conducción de tan importante actividad.

  13. Quaternary Slip History for the Agua Blanca Fault, northern Baja California, Mexico

    Science.gov (United States)

    Gold, P. O.; Behr, W. M.; Rockwell, T. K.; Fletcher, J. M.

    2017-12-01

    The Agua Blanca Fault (ABF) is the primary structure accommodating San Andreas-related right-lateral slip across the Peninsular Ranges of northern Baja California. Activity on this fault influences offshore faults that parallel the Pacific coast from Ensenada to Los Angeles and is a potential threat to communities in northern Mexico and southern California. We present a detailed Quaternary slip history for the ABF, including new quantitative constraints on geologic slip rates, slip-per-event, the timing of most recent earthquake, and the earthquake recurrence interval. Cosmogenic 10Be exposure dating of clasts from offset fluvial geomorphic surfaces at 2 sites located along the western, and most active, section of the ABF yield preliminary slip rate estimates of 2-4 mm/yr and 3 mm/yr since 20 ka and 2 ka, respectively. Fault zone geomorphology preserved at the younger site provides evidence for right-lateral surface displacements measuring 2.5 m in the past two ruptures. Luminescence dating of an offset alluvial fan at a third site is in progress, but is expected to yield a slip rate relevant to the past 10 kyr. Adjacent to this third site, we excavated 2 paleoseismic trenches across a sag pond formed by a right step in the fault. Preliminary radiocarbon dates indicate that the 4 surface ruptures identified in the trenches occurred in the past 6 kyr, although additional dating should clarify earthquake timing and the mid-Holocene to present earthquake recurrence interval, as well as the likely date of the most recent earthquake. Our new slip rate estimates are somewhat lower than, but comparable within error to, previous geologic estimates based on soil morphology and geodetic estimates from GPS, but the new record of surface ruptures exposed in the trenches is the most complete and comprehensively dated earthquake history yet determined for this fault. Together with new and existing mapping of tectonically generated geomorphology along the ABF, our constraints

  14. Hybrid system of generating electricity, solar eolic diesel San Juanico, Baja California Sur, Mexico; Sistema hibrido de generacion electrica, eolico solar diesel San Juanico, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Huerta, Javier [Comision Federal de Electricidad, La Paz, Baja California Sur (Mexico); Johnston, Peter [Technology Development, Arizona (United States); Napikoski, Chester [Generation Engineering, Arizona (United States); Escutia, Ricardo [Comision Federal de Electricidad, Baja California Sur (Mexico)

    2000-07-01

    The Comision Federal de Electricidad (CFE), and the northamerican electric company Arizona Public Service (APS), made an agreement of collaboration to develop a project of generating electricity with the use of renewable resources. The premises that where agreed on are the following: 1. Focus the project a rural community. 2. The cost of the whole project should be lower than compared to the interconnection to a conventional system. 3. Acceptance of the community, and the governmental authorities. 4. Sustentability of the operation of the system. Several technical and economical analysis where done, such as the evaluation of the solar and eolic resources, study of the environmental impact, negotiation agreements so it would be possible to obtain de economical resources from Niagara Mohawk (NIMO), and the USAID, all of this thru the supervising of the Sandia National Laboratories. After the anemometric and solar radiation measures where made, it was considered that the community of San Juanico, en Baja California Sur, Mexico, was the most feasible one, it was necessary also to consider the aspects of logistics, socials, size of the community and as a detonator for the economic activities of tourism and fishing. The APS formulated the executive project in accordance with the recommendations of the different areas of CFE. The project consists basically in the installation of 10 wind generators of 10 Kw, a battery bank for 432 KWh, plus a diesel generator for emergencies of 80 Kw. Besides the civil and electromechanical installation. It was necessary to involve the community in the knowledge and followup of the project form it's, considering that this factor would be essential, so it could be successful. Lamps of low consumption where installed on the houses and street lightning, to optimize the system. The patronato that is a civil association of the community, is in charge of the administration of the system, it receives support from personnel of CFE. The income

  15. Hybrid system of generating electricity, solar eolic diesel San Juanico, Baja California Sur, Mexico; Sistema hibrido de generacion electrica, eolico solar diesel San Juanico, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Huerta, Javier [Comision Federal de Electricidad, La Paz, Baja California Sur (Mexico); Johnston, Peter [Technology Development, Arizona (United States); Napikoski, Chester [Generation Engineering, Arizona (United States); Escutia, Ricardo [Comision Federal de Electricidad, Baja California Sur (Mexico)

    2000-07-01

    The Comision Federal de Electricidad (CFE), and the northamerican electric company Arizona Public Service (APS), made an agreement of collaboration to develop a project of generating electricity with the use of renewable resources. The premises that where agreed on are the following: 1. Focus the project a rural community. 2. The cost of the whole project should be lower than compared to the interconnection to a conventional system. 3. Acceptance of the community, and the governmental authorities. 4. Sustentability of the operation of the system. Several technical and economical analysis where done, such as the evaluation of the solar and eolic resources, study of the environmental impact, negotiation agreements so it would be possible to obtain de economical resources from Niagara Mohawk (NIMO), and the USAID, all of this thru the supervising of the Sandia National Laboratories. After the anemometric and solar radiation measures where made, it was considered that the community of San Juanico, en Baja California Sur, Mexico, was the most feasible one, it was necessary also to consider the aspects of logistics, socials, size of the community and as a detonator for the economic activities of tourism and fishing. The APS formulated the executive project in accordance with the recommendations of the different areas of CFE. The project consists basically in the installation of 10 wind generators of 10 Kw, a battery bank for 432 KWh, plus a diesel generator for emergencies of 80 Kw. Besides the civil and electromechanical installation. It was necessary to involve the community in the knowledge and followup of the project form it's, considering that this factor would be essential, so it could be successful. Lamps of low consumption where installed on the houses and street lightning, to optimize the system. The patronato that is a civil association of the community, is in charge of the administration of the system, it receives support from personnel of CFE. The income that

  16. Mapping mantle-melting anomalies in Baja California: a combined subaereal-submarine noble gas geochemistry new data set.

    Science.gov (United States)

    Spelz, R. M.; Negrete-Aranda, R.; Hilton, D. R.; Virrueta, C.; Tellez, M.; Lupton, J. E.; Evans, L. J.; Clague, D. A.; Zierenberg, R. A.; Neumann, F.

    2017-12-01

    In active tectonic settings, the presence of helium in aqueous fluids with 3He/4He ratios greater than in-situ production values ( 0.05 RA where RA = air He or 1.4 x 10-6) indicates the contribution of mantle-derived volatiles to the total volatile inventory. This is an indicative of the presence of mantle-derived melts, which act to transfer volatiles from the solid Earth towards the surface. Thus, He has the potential to map regions of the underlying mantle which are undergoing partial melting - a phenomenon which should also be evident in the seismic record. Reports of high 3He/4He in hot springs in Baja California (BC) has prompted us to initiate a survey of the region to assess relationship(s) between He isotopes and geophysical images of the underlying mantle. Previous studies report 3He/4He ratios of 0.54 RA for submarine hot springs (Punta Banda 108oC) and 1.3 RA for spring waters (81oC) at Bahia Concepcion. Our new survey of hot springs in northern BC has revealed that all 12 localities sampled to date, show the presence of mantle He with the highest ratio being 1.74RA (21% mantle-derived) at Puertecitos on the Gulf coast. He ratios are generally lower on the Pacific coast with the minimum mantle He contribution being 5% at Santa Minerva (0.11RA). Thus, preliminary trends are of a west-to-east increase in the mantle He signal across the peninsula. In the Gulf of California, recent He analyses from the newly discovered Meyibo (350 °C) and Auka (250-290 °C) hydrothermal fields at Alarcon rise and Pescadero basin, respectively, show high 3He/4He ratios ( 8RA), typical of MORB's. These ratios are higher than the ones reported for Guaymas Basin (6.95 RA), suggesting that primordial He signal from the mantle increases following a North-South direction along the Gulf axis. He results presented in this study correlate well with high resolution Rayleigh wave tomography images by DiLuccio et al (2014). Shear velocity variations in the BC crust and upper mantle

  17. Quantifying the Forcing Factors Responsible for the Tectono-Geomorphological Evolution of Neogene Rift Basins, Baja California

    Science.gov (United States)

    El-Sobky, H. F.; Dorobek, S. L.

    2005-12-01

    The Gulf of California and its surrounding land areas provide a classic example of recently rifted continental lithosphere, where back-arc stretching of a continental volcanic arc has culminated in the ongoing seafloor spreading that characterizes the present-day axis of the gulf. The recent tectonic history of eastern Baja California, which includes most of the land area eastward of the main drainage divide that extends north-south along the length of the peninsula, has been dominated by oblique rifting that began at about 5 Ma. Thus, extensional tectonics, bedrock lithology, long-term climatic changes, and evolving surface processes have controlled the tectono-geomorphological evolution of the eastern part of the peninsula since 5 Ma. No previous studies, however, examined the effect of these combined factors on the current tectono-geomorphological characteristics of eastern Baja California. We assume that although long-term climate may have changed along the peninsula over the last several million years, precipitation amounts are likely to have changed in a similar way along the entire length of the peninsula, regardless of the long-term climatic trend. This suggests that climatic variation can be largely ruled out as an explanation for the geomorphologic variability between basins. In an attempt to quantify the factors that affected the geomorphologic development along the eastern side of Baja California, thirty-four drainage basins were extracted from a 15-m-resolution absolute digital elevation model (DEM). The stacked-vector method was applied to utilize the different terrain attributes (e.g., hillshaded relief, aspect, slope, etc.) for supervised classification of bedrock lithologies using object-oriented techniques. Stream-length gradient indices were then measured for the main stream in each of the basins. Bedrock lithologies and alluvium were plotted along the stream profiles to identify any relationship between lithology, structure, and stream gradient

  18. Transformations of Mangrove Forests in Bahia Magdalena, Baja California Sur, Mexico: Two Decade Results Based on Landsat Imageries

    Science.gov (United States)

    Suresh Babu, S.; Abdul Rahaman, S.; Muthushankar, G.; Jonathan, M. P.

    2014-12-01

    Mangrove forests which thrive along the tropical and subtropical regions are the most productive ecosystems in the world with a wide range of ecological and economical services to mankind. With the rapid urbanization across the globe, these forests tend to be destroying at an alarming rate. The area of concern for this study, Bahia Magdalena is very important for the economy of the state as nearly 50% of the artisan fisheries are established in the mangrove zone. Henceforth this study is an attempt for a regional assessment and to accurately quantify the mangroves using LANDSAT imageries for over two decades in Bahia Magdalena, Baja California. Satellite imageries from the year 1986 through 2014 were analysed to assess the prolonged changes taking place in and around the mangrove reserve. Using the estimates of land use/cover for all the years, the spatio - temporal data was validated using ArcGIS software. The results revealed that the spatial extent of mangroves are decreasing until 2005 due to the developmental plans such as tourism, shrimp farming and establishment of industries in this part of the country. During the past 10 years (~ after 2005) there is no much change in the area extent of mangrove reserves due to afforestation and conservation efforts. Thus the unbiased dataset generated may be widely used for an improved understanding of the role of mangrove forests in the socio economic aspects, protection from natural disasters, identify possible areas for conservation, restoration and rehabilitation; and improve estimates of the amount of carbon stored in mangrove vegetation and the associated marine environment. Keywords: Mangroves, LANDSAT, Bahia Magdalena, México.

  19. The 2010 M w 7.2 El Mayor-Cucapah Earthquake Sequence, Baja California, Mexico and Southernmost California, USA: Active Seismotectonics along the Mexican Pacific Margin

    Science.gov (United States)

    Hauksson, Egill; Stock, Joann; Hutton, Kate; Yang, Wenzheng; Vidal-Villegas, J. Antonio; Kanamori, Hiroo

    2011-08-01

    The El Mayor-Cucapah earthquake sequence started with a few foreshocks in March 2010, and a second sequence of 15 foreshocks of M > 2 (up to M4.4) that occurred during the 24 h preceding the mainshock. The foreshocks occurred along a north-south trend near the mainshock epicenter. The M w 7.2 mainshock on April 4 exhibited complex faulting, possibly starting with a ~M6 normal faulting event, followed ~15 s later by the main event, which included simultaneous normal and right-lateral strike-slip faulting. The aftershock zone extends for 120 km from the south end of the Elsinore fault zone north of the US-Mexico border almost to the northern tip of the Gulf of California. The waveform-relocated aftershocks form two abutting clusters, each about 50 km long, as well as a 10 km north-south aftershock zone just north of the epicenter of the mainshock. Even though the Baja California data are included, the magnitude of completeness and the hypocentral errors increase gradually with distance south of the international border. The spatial distribution of large aftershocks is asymmetric with five M5+ aftershocks located to the south of the mainshock, and only one M5.7 aftershock, but numerous smaller aftershocks to the north. Further, the northwest aftershock cluster exhibits complex faulting on both northwest and northeast planes. Thus, the aftershocks also express a complex pattern of stress release along strike. The overall rate of decay of the aftershocks is similar to the rate of decay of a generic California aftershock sequence. In addition, some triggered seismicity was recorded along the Elsinore and San Jacinto faults to the north, but significant northward migration of aftershocks has not occurred. The synthesis of the El Mayor-Cucapah sequence reveals transtensional regional tectonics, including the westward growth of the Mexicali Valley and the transfer of Pacific-North America plate motion from the Gulf of California in the south into the southernmost San

  20. Inseguridad y Crisis Económica en el Imaginario Social de Playas de Rosarito, Baja California

    OpenAIRE

    Jesús Angel Enríquez Acosta; Alejandra Meza; Noelia Fierro

    2015-01-01

    Este trabajo ofrece un análisis acerca de como los habitantes de Playas de Rosarito en Baja California, imaginan y perciben el impacto de la crisis económica norteamericana mas reciente y la inseguridad mexicana en la actividad turística, principal vocación económica del lugar. Los testimonios de los habitantes expresan la transformación social, urbana y cultural del lugar turístico y de los problemas asociados a ciudades en rápido crecimiento. Se trata de una ciudad fronteriza con Estados Un...

  1. Sex education and gender vs. abuse in relationships. Scenario on violence in young people in Baja California

    Directory of Open Access Journals (Sweden)

    Teresa Fernández de Juan

    2014-11-01

    Full Text Available Violence in the relationships of courtship among young people presents growing demonstrations at international and national levels, as it occurs with the increase in the diseases of HIV/AIDS, adolescent pregnancy and sexual transmission. This work emphasizes the main strategy for the prevention of both risk behaviour is directly related to the implementation of an efficient, unprejudiced and timely sex education, especially in schools, with a gender perspective, which is lacking in general sense, at home and in Baja California in particular.

  2. Bedforms, Channel Formation, and Flow Stripping in the Navy Fan, Offshore Baja California

    Science.gov (United States)

    Carvajal, C.; Paull, C. K.; Caress, D. W.; Fildani, A.; Lundsten, E. M.; Anderson, K.; Maier, K. L.; McGann, M.; Gwiazda, R.; Herguera, J. C.

    2017-12-01

    Deep-sea fans store some of the largest volumes of siliciclastic sediment in marine basins. These sandy accumulations record the history of sediment transfer from land to sea, serving as direct records of the geologic history of the continents. Despite their importance, deep-sea fans are difficult to study due to their remote locations in thousands of meters of water depth. In addition, deep-sea fans have a low relief, and geomorphological changes important for the evolution of the fan are often too subtle to be adequately resolved by 3D seismic data or surface-ship bathymetry. To improve our understanding of deep-sea fans, an autonomous underwater vehicle (AUV) was used to acquire high-resolution bathymetry and sub-bottom CHIRP profiles in the proximal sectors of the Navy Fan, offshore Baja California. A remotely operated vehicle was also used to acquire vibracores. The 1-m grid resolution bathymetry shows the seafloor geomorphology in extreme detail revealing different kinds of bedforms, which in combination with the vibracores help to interpret the sedimentary processes active during the Holocene. Morphological elements in the survey area include a main channel, numerous scours, an incipient channel, sediment waves, and a fault escarpment. Several of the scours are interpreted to result from flow stripping at a bend in the main channel. Along high gradient sectors (e.g. > 1o), the scours form bedforms with an erosionally truncated headwall immediately followed down-dip by an upflow accreting sedimentary bulge. These bedforms, the presence of clean sands in the scours and the high gradients suggest that these scours are net-erosional cyclic steps. Scours seem to coalesce along the sediment transport direction to form an incipient channel with abundant rip-up clast gravels. Elsewhere in the survey area, scours are elongated and intimately associated with sediment waves. The acquired dataset illustrates that deep-sea fans may show a variety of processes and

  3. Lanthanide behavior in hypersaline evaporation ponds at Guerrero Negro, Baja California, Mexico - an environment with halophiles

    Science.gov (United States)

    Choumiline, K.; López-Cortés, A.; Grajeda-Muñoz, M.; Shumilin, E.; Sapozhnikov, D.

    2013-12-01

    Lanthanides are known, in some cases, to be sensitive to changes in water column or sediment chemistry, a fact that allows them to be used as environmental fingerprints. Nevertheless, the behavior of these elements in hypersaline environments is insufficiently understood, especially in those colonized by bacteria, archaea and eukarya halophiles. Extreme environments like the mentioned exist in the artificially-controlled ponds of the 'Exportadora de Sal' salt-producing enterprise located in Guerrero Negro (Baja California, Mexico). Sediment cores from various ponds were collected, subsampled and measured by ICP-MS and INAA. This allowed differencing the behavior of lanthanides and trace elements under a water column salinity gradient along the evaporation sequence of ponds. Sediment profiles (30 mm long), obtained in Pond 5, dominated by Ca and Mg precipitation and at the same time rich in organic matter due to bacterial mat presence, showed highs and lows of the shale-normalized patterns along different in-core depths. Two groups of elements could be distinguished with similar trends: set A (La, Ce, Pr and Nd) and set B (Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). The first 'group A' had two prominent peaks at 15 mm and around 22 mm, whereas the 'group B' showed only slight increase at 15 mm and none at 22 mm. Microscopic analyses of prokaryotic cells of a stratified mat in Pond 5 (collected in 2004) showed filamentous bacteria and cyanobacteria with a cell abundance and morphotype richness maxima of prokaryotic cells in a chemocline from 3 mm to 7 mm depth which co-exists nine morphotypes of aerobic and anaerobic prokaryotes Microcoleus chthonoplastes, Leptolyngbya, Cyanothece, Geitlerinema, Spirulina, Chloroflexus, Beggiatoa, Chromatium and Thioploca. Below the 7 mm depth, oxygenic photosynthesis depletes and sulfur reducing compounds increase. The highs of the shale-normalized lanthanide contents of the 'group A' (at 15 mm depth) seem to correlate with the

  4. Decreased Anemia Prevalence Among Women and Children in Rural Baja California, Mexico: A 6-Year Comparative Study.

    Science.gov (United States)

    Moor, Molly A; Fraga, Miguel A; Garfein, Richard S; Harbertson, Judith; Rodriguez-Lainz, Alfonso; Rashidi, Hooman H; Elder, John P; Brodine, Stephanie K

    2016-08-01

    Anemia is a public health problem in Mexico. This study sought to determine the prevalence and correlates of anemia among women and children residing in a rural farming region of Baja California, Mexico. An existing partnership between universities, non-governmental organizations, and an underserved Mexican community was utilized to perform cross-sectional data collection in 2004-2005 (Wave 1) and in 2011-2012 (Wave 2) among women (15-49 years) and their children (6-59 months). All participants completed a survey and underwent anemia testing. Blood smears were obtained to identify etiology. Nutrition education interventions and clinical health evaluations were offered between waves. Participants included 201 women and 99 children in Wave 1, and 146 women and 77 children in Wave 2. Prevalence of anemia significantly decreased from 42.3 to 23.3 % between Waves 1 and 2 in women (p children 24-59 months (p = 0.066), and from 71.4 to 45.8 % in children 6-23 months (p = 0.061). Among women in Wave 1, consumption of iron absorption enhancing foods (green vegetables and fruits high in vitamin C) was protective against anemia (p = 0.043). Women in Wave 2 who ate ≥4 servings of green, leafy vegetables per week were less likely to be anemic (p = 0.034). Microscopic examination of blood smears revealed microcytic, hypochromic red blood cells in 90 % of anemic children and 68.8 % of anemic women, consistent with iron deficiency anemia.

  5. Candida species diversity and antifungal susceptibility patterns in oral samples of HIV/AIDS patients in Baja California, Mexico.

    Science.gov (United States)

    Clark-Ordóñez, Isadora; Callejas-Negrete, Olga A; Aréchiga-Carvajal, Elva T; Mouriño-Pérez, Rosa R

    2017-04-01

    Candidiasis is the most common opportunistic fungal infection in HIV patients. The aims of this study were to identify the prevalence of carriers of Candida, Candida species diversity, and in vitro susceptibility to antifungal drugs. In 297 HIV/AIDS patients in Baja California, Mexico, Candida strains were identified by molecular methods (PCR-RFLP) from isolates of oral rinses of patients in Tijuana, Mexicali, and Ensenada. 56.3% of patients were colonized or infected with Candida. In Tijuana, there was a significantly higher percentage of carriers (75.5%). Out of the 181 strains that were isolated, 71.8% were Candida albicans and 28.2% were non-albicans species. The most common non-albicans species was Candida tropicalis (12.2%), followed by Candida glabrata (8.3%), Candida parapsilosis (2.2%), Candida krusei (1.7%), and Candida guilliermondii (1.1%). Candida dubliniensis was not isolated. Two associated species were found in 11 patients. In Mexicali and Ensenada, there was a lower proportion of Candida carriers compared to other regions in Mexico and worldwide, however, in Tijuana, a border town with many peculiarities, a higher carrier rate was found. In this population, only a high viral load was associated with oral Candida carriers. Other factors such as gender, use of antiretroviral therapy, CD4+ T-lymphocyte levels, time since diagnosis, and alcohol/ tobacco consumption, were not associated with Candida carriers. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. An application of neural network in geophysical prospecting. Electrical resistivity at Las Virgenes geothermal field, Baja California Sur, Mexico; Una aplicacion de las redes neuronales a la prospeccion geofisica. Resistividad electrica en las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Palma Guzman, Sergio Hugo [Comision Federal de Electricidad, Morelia, Michoacan (Mexico)

    2000-12-01

    The technology of the neural network is presented with geophysical focus in the Las Virgenes geothermal field, Baja California Sur, Mexico. The results obtained when extrapolating the associative data of the prospecting magnetoteluria and Vertical Electric Sounding, on the area of the geothermal wells to the rest of the area, allows to classify zones of interest for the geothermal exploitation. Also, the use of these associative parameters with the information of the stabilized temperature of the wells, they allow to predict temperatures for the rest of the area. [Spanish] Se presenta una aplicacion de la tecnologia de las redes neuronales con enfoque geofisico en el campo geotermico de Las Virgenes, Baja California Sur, Mexico. Los resultados obtenidos al extrapolar los datos asociativos de las prospecciones geoelectricas de magnetoteluria y sondeos electricos verticales, en la zona de los pozos geotermicos al resto del area, permiten clasificar zonas de interes para la explotacion geotermica. Tambien, la utilizacion de estos parametros asociativos con la informacion de la temperatura estabilizada de los pozos, permiten predecir temperaturas para la misma area.

  7. Avistamientos recientes de águila real (Aquila chrysaetos en la sierra El Mechudo, Baja California Sur, México Recent sightings of Golden Eagle (Aquila chrysaetos in the Sierra El Mechudo, Baja California Sur, Mexico

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    Israel Guerrero-Cárdenas

    2013-03-01

    Full Text Available Se reportan nuevos avistamientos de águila real durante 3 años consecutivos (2007-2010 en 2 localidades de la sierra El Mechudo (El Saucito y las Tarabillas, Baja California Sur. Los avistamientos, se realizaron con cámaras-trampa y por observación directa. En BCS, los registros más recientes son de la sierra de la Laguna en el 2000. Se han detectado al menos 4 individuos diferentes, entre juveniles y adultos. La importancia de estos nuevos avistamientos reside en que por primera vez se registra la presencia del águila real en cuerpos de agua dulce.We report new sightings of Golden Eagle for 3 consecutive years (2007-2010 at 2 localities of the Sierra El Mechudo (El Saucito and Tarabillas, Baja California Sur. These sightings were recorded with camera traps and by direct observation. Most recent records from BCS are for the Sierra de la Laguna in 2000. At least 4 different individuals, both juveniles and adults, have been recorded. The importance of these new sightings is that for the first time we registered Golden Eagles infresh water wetlands.

  8. Rapid subsidence and stacked Gilbert-type fan deltas, Pliocene Loreto basin, Baja California Sur, Mexico

    Science.gov (United States)

    Dorsey, Rebecca J.; Umhoefer, Paul J.; Renne, Paul R.

    1995-08-01

    Pliocene nonmarine to marine sedimentary rocks exposed in the Loreto basin, Baja California Sur, provide a record of syntectonic subsidence and sedimentation in a transform-rift basin that developed along the western margin of the Gulf of California. A thick sequence of twelve Gilbert-type fan deltas, having a total measured thickness of about 615 m, accumulated near the fault-bounded southwestern margin of this basin. Based on stratal geometries and lithofacies associations, sedimentary rocks are divided into Gilbert-delta topset, foreset and bottomset strata, shell beds and background shallow-marine shelf deposits. Topset strata of each Gilbert-type delta cycle are capped by laterally persistent molluscan shell beds containing diverse assemblages of bivalves, pectens, oysters, gastropods and echinoids. These shell beds are interpreted to be condensed intervals that record sediment starvation during abandonment of the fan-delta plain. Delta abandonment may have been caused by large episodic faulting events, which submerged each pre-existing fan-delta plain, substantially slowed detrital input by drowning of alluvial feeder channels, and created new accommodation space for each new Gilbert-type fan delta. Alternatively, it is possible that delta-plain abandonment was caused by upstream avulsions and autocyclic lateral switching of fan-delta lobes during relatively uniform rates of slip along the basin-bounding fault. Two contrasting, plausible basin models are proposed for the Loreto basin: (1) asymmetric subsidence along a high-angle oblique-slip normal fault, producing a classic half-graben basin geometry with vertically stacked Gilbert-type fan deltas; or (2) lateral stacking and horizontal displacement of strata away from a relatively fixed depocenter due to fault movement in the releasing bend of a listric strike-slip fault. We favor the first model because field relations and simple geometric constraints suggest that most of the total measured section

  9. Magnetic Fabric and Paleomagnetism of the Peninsular Ranges Batholith, Sierra San Pedro M rtir, Baja California.

    Science.gov (United States)

    Knight, M.; Herrero-Bervera, E.; Molina-Garza, R. S.; Böhnel, H. N.

    2003-12-01

    We summarize results of recent paleomagnetic, structural, petrologic and magnetic fabric studies along an east-west (60 km long) transect across the Peninsular Ranges Batholith (PRB) in north-central Baja California. The transect includes both magnetite rich plutons from the western sector of the PRB, and ilmenite rich plutons from the eastern sector, as well as plutons on the eastern and western side of major tectonic discontinuities. We include results for 8 plutons, included well-characterized bodies such as San Pedro M rtir (SP), San José (SJ) and La Zarza (LZ), and relatively little known plutons such as Potrero (PO), Aguaje del Burro (AB), El Milagro (MI), and San Telmo (ST). Plutons on the western sector of the PRB yield a paleomagnetic pole at 82° N-186.4° E (A95=4.8° ). When rotated into a pre- Gulf of California position, the pole (79.2° -188.2° ) is statistically undistinguishable from the North American reference pole. In contrast, SP, SJ and PO plutons, on either side of the NW trending Main Martir Thrust yield clearly discordant direction that can only be reconciled with results for the western plutons assuming southwestward tilt of ˜ 25° for SP and greater than 45° for SJ and PO. We find strong evidence in support of tilt of the plutons from thermochronological, structural, and geobarometric data. These data will be discussed elsewhere. Here we focus on magnetic fabric data. AMS for SJ is strongly developed with high values for degree of anisotropy (P= 1.14 a 1.40), but marked east-west asymmetry that contrasts with the general symmetry of the pluton along a north-south axis. Oblate fabrics (T ˜ +0.4) with dispersed lineation directions dominate the west side of the pluton and prolate fabrics (T ˜ -0.15) with steep to vertical lineations dominate on its eastern side. This fabric is interpreted to result from magma flow. SP, a much larger pluton and sensibly asymmetric, displays high degrees of anisotropy (P ˜1.2) on its western side but

  10. Testing Pixel Translation Digital Elevation Models to Reconstruct Slip Histories: An Example from the Agua Blanca Fault, Baja California, Mexico

    Science.gov (United States)

    Wilson, J.; Wetmore, P. H.; Malservisi, R.; Ferwerda, B. P.; Teran, O.

    2012-12-01

    We use recently collected slip vector and total offset data from the Agua Blanca fault (ABF) to constrain a pixel translation digital elevation model (DEM) to reconstruct the slip history of this fault. This model was constructed using a Perl script that reads a DEM file (Easting, Northing, Elevation) and a configuration file with coordinates that define the boundary of each fault segment. A pixel translation vector is defined as a magnitude of lateral offset in an azimuthal direction. The program translates pixels north of the fault and prints their pre-faulting position to a new DEM file that can be gridded and displayed. This analysis, where multiple DEMs are created with different translation vectors, allows us to identify areas of transtension or transpression while seeing the topographic expression in these areas. The benefit of this technique, in contrast to a simple block model, is that the DEM gives us a valuable graphic which can be used to pose new research questions. We have found that many topographic features correlate across the fault, i.e. valleys and ridges, which likely have implications for the age of the ABF, long term landscape evolution rates, and potentially provide conformation for total slip assessments The ABF of northern Baja California, Mexico is an active, dextral strike slip fault that transfers Pacific-North American plate boundary strain out of the Gulf of California and around the "Big Bend" of the San Andreas Fault. Total displacement on the ABF in the central and eastern parts of the fault is 10 +/- 2 km based on offset Early-Cretaceous features such as terrane boundaries and intrusive bodies (plutons and dike swarms). Where the fault bifurcates to the west, the northern strand (northern Agua Blanca fault or NABF) is constrained to 7 +/- 1 km. We have not yet identified piercing points on the southern strand, the Santo Tomas fault (STF), but displacement is inferred to be ~4 km assuming that the sum of slip on the NABF and STF is

  11. Growth and mortality of the fish Citharichthys xanthostigma (Pleuronectiformes: Paralichthyidae off the Western coast of Baja California, México

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    Marco A Martínez-Muñoz

    2010-06-01

    Full Text Available Longfin sanddab (Citharichthys xanthostigma represents a very important fishery resource in Southern and Baja California but are not very well known. The purpose of this study is to provide information on the growth and mortality of longfin sanddab population in the Mexican Pacific Ocean at Baja California, México. Data on growth were obtained for longfin sanddab collected with otter trawls during six cruises off the Western coast of Baja California. A total of 1 017 longfin sanddab were caught over the sampling period, and from 860 specimens, the male to female ratio was 1:1.8. The relationship between total weight (W and standard length (SL is described: W=0.00000743 SL3.196 for females and W=0.00000764 SL3.193 for males. Age groups were estimated from length frequency data, and von Bertalanffy annual growth parameters for all fish data combined were the following: L∞=289.2mm SL, k=0.20, t0=-0.73; for males, they were L∞=265.9mm SL, k=0.21, t0=-0.68, and for females, L∞=293.6mm SL, k=0.23, t0=-0.35. Longfin sanddab caught during this study reached a maximum age of 10 years, and at that age, males attained smaller sizes than females. The age groups had a total mortality (Z rate of 0.82 year-1, a fishing mortality (F of 0.52 year-1, and a natural mortality (M of 0.3 year-1. Although the longfin sanddab is not a target species of commercial fisheries, it suffers high mortality as part of the bycatch in the shrimp fishery. Rev. Biol. Trop. 58 (2: 689-705. Epub 2010 June 02.Se presenta información sobre el crecimiento y mortalidad de la población del C. xanthostigma (lenguado alón en el Pacífico Mexicano de Baja California, México. Datos sobre su crecimiento fueron obtenidos de peces capturados con red de arrastre durante seis cruceros en la costa Oeste de Baja California, México. Se capturaron 1 017 peces en este periodo. La relación machos:hembras de 860 ejemplares fue de 1:1.2. La relación peso total (W y longitud estándar (SL se

  12. View of an intact oceanic arc, from surficial to mesozonal levels: Cretaceous Alisitos arc, Baja California

    Science.gov (United States)

    Busby, Cathy; Fackler Adams, Benjamin; Mattinson, James; Deoreo, Stephen

    2006-01-01

    The Alisitos arc is an approximately 300 × 30 km oceanic arc terrane that lies in the western wall of the Peninsular Ranges batholith south of the modern Agua Blanca fault zone in Baja California. We have completed detailed mapping and dating of a 50 × 30 km segment of this terrane in the El Rosario to Mission San Fernando areas, as well as reconnaissance mapping and dating in the next 50 × 30 km segment to the north, in the San Quintin area. We recognize two evolutionary phases in this part of the arc terrane: (I) extensional oceanic arc, characterized by intermediate to silicic explosive and effusive volcanism, culminating in caldera-forming silicic ignimbrite eruptions at the onset of arc rifting, and (II) rifted oceanic arc, characterized by mafic effusive and hydroclastic rocks and abundant dike swarms. Two types of units are widespread enough to permit tentative stratigraphic correlation across much of this 100-km-long segment of the arc: a welded dacite ignimbrite (tuff of Aguajito), and a deepwater debris-avalanche deposit. New U-Pb zircon data from the volcanic and plutonic rocks of both phases indicate that the entire 4000-m-thick section accumulated in about 1.5 MY, at 111-110 MY. Southwestern North American sources for two zircon grains with Proterozoic 206Pb / 207Pb ages support the interpretation that the oceanic arc fringed North America rather than representing an exotic terrane. The excellent preservation and exposure of the Alistos arc terrane makes it ideal for three-dimensional study of the structural, stratigraphic and intrusive history of an oceanic arc terrane. The segment mapped and dated in detail has a central major subaerial edifice, flanked by a down-faulted deepwater marine basin to the north, and a volcano-bounded shallow-water marine basin to the south. The rugged down-faulted flank of the edifice produced mass wasting, plumbed large-volume eruptions to the surface, and caused pyroclastic flows to disintegrate into turbulent

  13. TURISMO MÉDICO EN LOS ALGODONES, BAJA CALIFORNIA, MÉXICO: EXPLORACIÓN DEL CAPITAL HUMANO

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    Sonia Guadalupe Zermeño-Flores

    2016-06-01

    Full Text Available El presente documento es una exploración del capital humano (CH de los profesionistas de salud respecto a la capacitación y el desarrollo de conocimientos, habilidades y actitudes en la prestación de servicios médicos al paciente-turista de Vicente Guerrero, mejor conocido como Los Algodones (LAL en el Estado de Baja California. Éste se distingue por ofrecer a los visitantes que llegan principalmente del norte de Estados Unidos y Canadá durante la temporada de invierno servicios de salud, especialmente en el campo de la higiene dental y la optometría, así como venta de medicamentos A esto se agregan las estrategias de competitividad en la frontera de Baja California (México y California (Estados Unidos. El presente artículo es tanto un estudio cuantitativo como cualitativo, que comprende tres etapas. La primera etapa consistió en la revisión de literatura del turismo médico (TM y sus implicaciones para el capital humano. La segunda etapa fue la consulta de datos básicos de la entidad, que se sometió al análisis estadístico de los profesionistas instalados oficialmente en las empresas que operan en el TM. La tercera etapa se enfocó en la realización de entrevistas a profundidad a profesionistas de la salud de alto prestigio en la sociedad de Los Algodones.

  14. Composición del aceite esencial de Tagetes lacera, planta endémica de Baja California Sur, México Composition of essential oil of Tagetes lacera, endemic plant from Baja California Sur, Mexico

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    Francisco Díaz-Cedillo

    2012-06-01

    Full Text Available Es escasa la información sobre la biología y química de Tagetes lacera Brand. (Asteraceae, especie endémica de Baja California Sur (BCS, México, que por su porte alto y presencia de aroma es una fuente de aceites esenciales útil para el control de plagas y enfermedades de cultivos agrícolas. A partir de partes aéreas de plantas en floración de T. lacera recolectadas en la sierra de la Laguna, BCS se obtuvo aceite esencial mediante hidrodestilación. Por medio del procedimiento de análisis CG-EM, se identificaron 6 compuestos principales: E-tagetona (26.2%, crisantenona (24.8%, verbenona (22.1%, α-thujeno (20.5%, β-pineno (3.1% y α-pineno (1.9%.It is scarce the background on the biology and chemistry of Tagetes lacera Brand. (Asteraceae, an endemic species from Baja California Sur (BCS, Mexico that considering its plant high and odor is an essential oil source to obtain biopesticides. From aerial parts of plants fully flowered of T. lacera picked in Sierra de la Laguna, BCS, essential oil was obtained by hydrodistillation. Using GC-MS analysis, 6 major compounds were identified: E-tagetone (26.2%, chrysanthenone (24.8%, verbenone (22.1%, α-thujene (20.5%, β-pinene (3.1%, α-pinene (1.9%.

  15. A Study on the Attitudes and Opinions of Engineering Students from the University of Baja California, Mexico, on Science, Technology, and Society

    Science.gov (United States)

    Oliveros Ruiz, Maria Amparo; Sevilla Garcia, Juan Jose; Schorr, Michael

    2010-01-01

    A proposal is presented for the incorporation of the concepts of STS into the teaching of science and technology at the Faculty of Engineering, Mexicali Campus, of the University of Baja California. The method outlined for the development of research and the application of the "Opinions Questionnaire on Science, Technology and Society"…

  16. Perros ferales en la isla de Cedros, Baja California, México: una posible amenaza para los pinnípedos Feral dogs at Isla de Cedros, Baja California, Mexico: a possible threat for pinnipeds

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    María Concepción García-Aguilar

    2012-09-01

    Full Text Available La presencia de perros ferales (Canis lupus familiaris en la isla de Cedros, Baja California, México, fue documentada hace más de 15 años. En el verano de 2009 e invierno 2009/2010, se realizaron 2 campañas de muestreo en la costa noreste de la isla para evaluar los hábitos alimentarios de los perros en las cercanías de las zonas de reproducción y descanso del lobo marino de California (Zalophus californianus y del elefante marino del norte (Mirounga angustirostris. Los mamíferos constituyeron el grupo consumido más importante en la alimentación de los perros (85.4%. Los resultados de este estudio muestran que en la costa noreste de la isla de Cedros los perros se alimentan de pinnípedos: el elefante marino fue la especie que más se consumió, con el mayor porcentaje en ambas temporadas (43.3% en verano y 51.9% en invierno; el lobo marino, fue la segunda durante el verano (23.3%, aunque su porcentaje disminuyó en el invierno (5.8%. Además del potencial impacto que el consumo por los perros pueda tener sobre las poblaciones de los pinnípedos, una amenaza adicional es la posible transmisión de los patógenos caninos, con serias consecuencias epizoóticas.The presence of feral dogs (Canis lupus familiaris in Isla de Cedros, Baja California, Mexico, has been documented for over 15 years. In the summer of2009 and the winter of 2009/2010, 2 sampling surveys were conducted in the northeast coastal portion of the island to assess the diet of feral dogs in the vicinity of hauled out California sea lions (Zalophus californianus and northern elephant seals (Mirounga angustirostris. Mammals were the most important prey group in the diet of dogs (85.4%. Our results show that in the northeast coast of Isla de Cedros, feral dogs feed on pinnipeds: the elephant seal was the most important prey in both seasons (43.3% in summer and 51.9% in winter, followed by the sea lion as the second most important prey during the summer (23.3%, while its

  17. Trabajadores agrícolas migrantes en Baja California. Vinculación con la migración internacional

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    Ma. Eugenia Anguiano Téllez

    1989-09-01

    Full Text Available En este ensayo los jornaleros agrícolas migrantes son clasificados en dos estratos: el primero, considera la migración internacional, es decir, aquéllos que se internan en Estados Unidos con el propósito de conseguir empleo; y el segundo, corresponde a la migración interna de los trabajadores agrícolas que permanecen en Baja California para laborar en los valles de Mexicali y San Quintín.En este trabajo se señalan las diferencias entre estos dos estratos, tanto de carácter económico como en los niveles de educación; asimismo, se comparan las características de los jornaleros agrícolas migrantes que cruzan a Estados Unidos por Mexicali y por Tijuana, según su actividad económica de procedencia y su expectativa de empleo en los Estados Unidos.

  18. Mujer y nación: una historia de la educación en Baja California. 1920-1930

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    María del Consuelo López Arámburo

    2005-01-01

    Full Text Available This article forms part of research in progress that aims to examine the intellectual climate prevailing in Mexico in the post-revolutionary period, from 1920 to 1930. The essay explores how the influence of nationalist ideology gradually shifted the role of Mexican women, identifying them as the educators of the nation. The study focuses on Baja California since educators, such as Josefina Rendón Parra (1885-1977, were an important example illustrating how nationalist ideology engineered women´s role in Mexico´s reconstruction. Education with a spiritual dimension was the key doorway through which women gained access to the modern era. In a society that had yet to grant them the right to vote, education was also the doorway through which women gained acceptance as citizens. Finally, this study proposes the remaking of history through the mythological discourses, such as the legends that were fashionable in that period.

  19. Business competitiveness in the small and medium-sized enterprises of the manufacturing sector in Baja California

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    Manuel Alejandro Ibarra Cisneros

    2017-01-01

    Full Text Available The objective of this research is to determine the competitiveness level of the manufacturing small and medium-sized enterprises (SMEs of Baja California and to identify which areas within them affect this competitiveness. The methodology used is descriptive, correlational, and cross-sectional; the systemic competitiveness model is developed at the micro level, and a measurement instrument with 64 questions is used on 195 companies in the state; in addition, traditional multiple linear regressions are performed to test the hypotheses. One of the findings is that the SMEs in the state have a medium-low competitiveness level and do not show any relationship between the size of the companies and their competitiveness; however, the production-operations area prove to be more important for their competitiveness level. Although the measurement instrument that is used has no proportionality at the municipality and subsector level, it does allow us to approach the internal operation of the SMEs.

  20. Epiphytic diatoms associated with red mangrove (Rhizophora mangle prop roots in Bahía Magdalena, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    D.A Siqueiros Beltrones

    2006-06-01

    Full Text Available The first floristic inventory of benthic diatoms is provided for the Bahía Magdalena- Bahía Almejas lagoon system. Samplings were carried out during November of 1999. The oxydized samples were mounted permanently. Eighty six diatom taxa were identified, out of which 59 are new records for the Bahía Magdalena area, and 12 taxa are new for the Baja California peninsula. Taxa recorded previously as rare in other substrata are common or abundant on the epiphytic macroalgae of mangrove prop roots. Other species are mainly epipelic forms, while 24 are commonly found as tychoplankton in the area. Certain taxa appear to be characteristic of mangrove systems in general. Rev. Biol. Trop. 54(2: 287-297. Epub 2006 Jun 01.Se presenta el primer inventario florístico de diatomeas bénticas para el Sistema Lagunar Bahía Magdalena-Bahía Almejas. Se hicieron muestreos en noviembre de 1999. En las muestras oxidadas y montadas permanentemente, se identificaron 86 táxones, de los cuales 59 son nuevos registros para el área de Bahía Magdalena, y 12 son nuevos para la península de Baja California. Táxones previamente registrados como escasos en otros sustratos son comunes o abundantes sobre macroalgas epífitas de raíces primarias de mangle. Otras species son principalmente formas epipélicas, mientras que 24 son constituyentes comunes del ticoplancton del área. Ciertos táxones parecen ser característicos de sistemas de manglar en general.

  1. Key species and impact of fishery through food web analysis: A case study from Baja California Sur, Mexico

    Science.gov (United States)

    Rocchi, Marta; Scotti, Marco; Micheli, Fiorenza; Bodini, Antonio

    2017-01-01

    Ecosystem-Based Management (EBM) aims to support the protection of natural ecosystems and to improve economic activities. It requires considering all of the actors interacting in social-ecological systems (e.g., fish and fishers) in the understanding that their interplay determines the dynamic behavior of the single actors as well as that of the system as a whole. Connections are thus central to EBM. Within the ecological dimension of socio-ecological systems, interactions between species define such connections. Understanding how connections affect ecosystem and species dynamics is often impaired by a lack of data. We propose food web network analysis as a tool to help bridge the gap between EBM theory and practice in data-poor contexts, and illustrate this approach through its application to a coastal marine ecosystem in Baja California Sur, Mexico. First, we calculated centrality indices to identify which key (i.e., most central) species must be considered when designing strategies for sustainable resource management. Second, we analyzed the resilience of the system by measuring changes in food web structure due to the local extinction of vulnerable species (i.e., by mimicking the possible effect of excessive fishing pressure). The consequences of species removals were quantified in terms of impacts on global structural indices and species' centrality indices. Overall, we found that this coastal ecosystem shows high resilience to species loss. We identified species (e.g., Octopus sp. and the kelp bass, Paralabrax clathratus) whose protection could further decrease the risk of potential negative impacts of fishing activities on the Baja California Sur food web. This work introduces an approach that can be applied to other ecosystems to aid the implementation of EBM in data-poor contexts.

  2. Variabilidad de la abundancia de zooplancton en Bahía Magdalena Baja California Sur, México (1997-2001 Zooplankton abundance variability in Magdalena Bay, Baja California Sur, Mexico (1997-2001

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    Sergio Hernández-Trujillo

    2010-01-01

    Full Text Available Se analizaron muestras de zooplancton de 16 campañas oceanógraficas, efectuadas en Bahía Magdalena, Baja California Sur, México, entre agosto de 1997 y marzo de 2001. Se identificó un total de 26 grupos taxonómicos, de los cuales los más abundantes y frecuentes fueron copépodos y quetognatos; en 2000-2001 se observó una tendencia a disminuir entre 10 y 20 el número de grupos de zooplancton. La biomasa zooplanctónica y abundancia de copépodos disminuyeron en el periodo de estudio, en contraste con los quetognatos que tuvieron un ligero aumento. Las fluctuaciones de abundancia de zooplancton no estuvieron relacionadas con la concentración de clorofila-α, a diferencia de los máximos de abundancia de zooplancton, que estuvieron asociados a los cambios de la temperatura superficial del mar. El ciclo estacional de la abundancia del zooplancton en Bahía Magdalena, indicó que en invierno el promedió fue mayor de 65.000 ind 100 m-3 , valor que aumentó en primavera a más de 99.000 ind 100 m-3 , se mantuvo en verano alrededor de 100.000 ind 100 m-3 y en otoño descendió rápidamente a casi 40.000 ind 100 m-3.Zooplankton were studied from 16 oceanographic surveys carried out in Magdalena Bay, Baja California Sur, Mexico, between August 1997 and March 2001. Twenty-six taxonomic groups were identified, the most abundant and frequent of which were copepods and chaetognaths. In 2000-2001, the number of zooplankton groups tended to decrease by 10 to 20. Both zooplankton biomass and copepod abundance declined, unlike chaetognaths, which increased slightly. Fluctuations in zooplankton abundance were independent of the chlorophyll-a concentration, whereas the maximum zooplankton abundances were associated with changes in the sea surface temperature. The seasonal zooplankton abundance cycle in Magdalena Bay indicated that, in winter, the averaged was than 65,000 ind 100 m-3 , a value that increased to more than 99,000 ind 100 m-3 in spring

  3. Fauna de arañas del suelo de una comunidad árida-tropical en Baja California Sur, México Ground surface spider fauna in an arid tropical community in Baja California Sur, Mexico

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    María Luisa Jiménez

    2010-08-01

    Full Text Available Se describe la temporalidad y diversidad de arañas del suelo del matorral sarcocaule en la región del Cabo en Baja California Sur. Durante 1991-1992 se realizaron colectas semanales por medio de trampas de caída. Se capturaron 4 322 ejemplares de 53 especies. Las familias con mayor abundancia fueron Miturgidae (42.2%, Oonopidae (23.5%, Caponiidae (8.0% y Gnaphosidae (7.9%. Las especies más abundantes fueron Syspira tigrina Chamberlin (37.1%; Oonops nov. sp. (13.7%, Scaphiella hespera Chamberlin (7.8% y Tarsonops sternalis Chamberlin (5.2%, que constituyeron el 63.7% del total de individuos. Gnaphosidae fue la más rica en especies (11, seguida por Salticidae (7. La riqueza de especies fue constante durante todo el año, con un ligero ascenso en el verano (29 y una ligera disminución en el invierno (24. La diversidad por estación del año se mantuvo en un intervalo de H'= 3.3 -3.7. La abundancia relativa se incrementó en primavera y otoño. La mayor riqueza específica se encontró en otoño. La abundancia relativa y la diversidad de arañas se pueden considerar altas, a pesar del fuerte dominio de la familia Miturgidae. En la mayoría de las especies, la distribución mostró una marcada estacionalidad.Seasonal distribution, specific richness, and diversity of xeric shrub ground spiders were studied at a site in the Cape Region. Weekly collections of spiders were made in 1991-1992 using pit-fall traps. We captured 4 322 specimens in 53 families. Families with the highest number of individuals were: Miturgidae (42% Oonopidae (23.5%, Caponiidae (8.0%, and Gnaphosidae (7.9%. The most abundant species were Syspira tigrina Chamberlin (37.1%; Oonops nov. sp. (13.7%, Scaphiella hespera Chamberlin (7.8%, and Tarsonops sternalis Chamberlin (5.2%, representing 63.7% of the total specimens captured. Gnaphosidae was the richest in species (11 followed by Salticidae (7. Species richness was nearly constant during all the year, with a small increase in

  4. Numerical simulation of groundwater artificial recharge in a semiarid-climate basin of northwest Mexico, case study the Guadalupe Valley Aquifer, Baja California

    Science.gov (United States)

    Campos-Gaytan, J. R.; Herrera-Oliva, C. S.

    2013-05-01

    In this study was analyzed through a regional groundwater flow model the effects on groundwater levels caused by the application of different future groundwater management scenarios (2007-2025) at the Guadalupe Valley, in Baja California, Mexico. Among these studied alternatives are those scenarios designed in order to evaluate the possible effects generated for the groundwater artificial recharge in order to satisfy a future water demand with an extraction volume considered as sustainable. The State of Baja California has been subject to an increment of the agricultural, urban and industrials activities, implicating a growing water-demand. However, the State is characterized by its semiarid-climate with low surface water availability; therefore, has resulted in an extensive use of groundwater in local aquifer. Water level measurements indicate there has been a decline in water levels in the Guadalupe Valley for the past 30 years. The Guadalupe Valley aquifer represents one the major sources of water supply in Ensenada region. It supplies about 25% of the water distributed by the public water supplier at the city of Ensenada and in addition constitutes the main water resource for the local wine industries. Artificially recharging the groundwater system is one water resource option available to the study zone, in response to increasing water demand. The existing water supply system for the Guadalupe Valley and the city of Ensenada is limited since water use demand periods in 5 to 10 years or less will require the construction of additional facilities. To prepare for this short-term demand, one option available to water managers is to bring up to approximately 3.0 Mm3/year of treated water of the city of Ensenada into the valley during the low-demand winter months, artificially recharge the groundwater system, and withdraw the water to meet the summer demands. A 2- Dimensional groundwater flow was used to evaluate the effects of the groundwater artificial recharge

  5. Prevalencia e intensidad parasitaria en Mugil cephalus (Pisces: Mugilidae, del Río Colorado, Baja California, México

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    Martha E Valles-Ríos

    2000-06-01

    Full Text Available La prevalencia e intensidad parasitaria de la lisa cabezona, Mugil cephalus Linnaeus, 1758, fue cuantificada durante un ciclo anual (febrero 1994 a febrero 1995 en la confluencia de los ríos Colorado y Hardy, Baja California, México. Dos especies de parásitos fueron reconocidas: Contracaecum multipapillatum (von Drasche, 1882 (Ascaridida: Anisakidae y Ergasilus versicolor Wilson, 1911 (Poecilostomatoida: Ergasilidae. Las larvas del nematodo C. multipapillatum, representadas por dos estadíos (A y B, exhibieron prevalencias de 30% y 14.5%, respectivamente; mientras que el copépodo E. versicolor, mostró una prevalencia de 72.7%. La intensidad media de C. multipapillatum fue 6.18 y 2.37 parásitos/huésped para los estadíos A y B, respectivamente, y en E. versicolor, ésta fue de 4.01. El número de parásitos (táxones combinados incrementó con la talla del pez (r= 0.22, p= 0.02, pero fue independiente del factor de condición (K LP del huésped.The parasitic prevalence and mean intensity in the striped mullet, Mugil cephalus, was seasonally determined during an annual cycle (February 1994 to February 1995 in the confluence of the Colorado and Hardy rivers, Baja California, México. Two species of parasites were identified, a nematode, Contracaecum multipapillatum (von Drasche, 1882 (Ascaridida: Anisakidae, and a copepod, Ergasilus versicolor Wilson, 1911 (Poecilostomatoida: Ergasilidae. The larvae of C. multipapillatum, which were represented by two size classes (A and B stages, had prevalences of 30% and 14.5%, respectively; while A. versicolor had a prevalence of 72.7%. The mean intensity of C. multipapillatum was 6.18 and 2.37 individuals per infected fish for A and B stages, respectively; and for A. versicolor, it was of 4.01. The number of parasites (taxa combined increased with the size of fish (r= 0.22, p= 0.02, but it was independent of the host’s condition factor (K SL.

  6. Desalination and Water Security: The Promise and Perils of a Technological Fix to the Water Crisis in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Jamie McEvoy

    2014-10-01

    Full Text Available Across the globe, desalination is increasingly being considered as a new water supply source. This article examines how the introduction of desalinated water into the municipal water supply portfolio has affected water security in the coastal tourist city of Cabo San Lucas in Baja California Sur (BCS, Mexico. It also analyses the competing discourses surrounding desalination in the region and discusses alternative water management options for achieving water security. This article challenges the notion that desalination is an appropriate and sufficient technological solution for arid regions. The findings provide evidence of increased yet delimited water security at a neighbourhood scale while identifying new vulnerabilities related to desalination, particularly in the context of the global South. This article concludes that implementing a technological fix on top of a water management system that is plagued with more systemic and structural problems does little to improve long-term water management and is likely to foreclose or forestall other water management options. This multi-scalar analysis contributes to the emerging literature on water security by considering both a narrow and broad framing of water security and identifying a range of factors that influence water security.

  7. Análisis de la vulnerabilidad y resiliencia económica de Baja California en el contexto de la crisis financiera internacional

    Directory of Open Access Journals (Sweden)

    Salvador GONZÁLEZ ANDRADE

    2017-01-01

    Full Text Available Este trabajo analiza la vulnerabilidad económica y la resiliencia económica de Baja California, México, en el contexto de la crisis financiera internacional de 2007. Se propone una aproxima - ción metodológica para elaborar índices de vulnerabilidad y de resiliencia, y el desempeño económico de 2003 a 2014 se compara con el que tienen otras entidades. El desempeño econó - mico se mide desagregando el PIBE en sus componentes cíclico y no cíclico (tendencia. Se con - cluye que ante el shock externo, Baja California posee vulnerabilidad económica, pero también presenta una destacada resiliencia económica.

  8. Biomonitoring with Micronuclei Test in Buccal Cells of Female Farmers and Children Exposed to Pesticides of Maneadero Agricultural Valley, Baja California, Mexico

    OpenAIRE

    Idalia Jazmin Castañeda-Yslas; María Evarista Arellano-García; Marco Antonio García-Zarate; Balam Ruíz-Ruíz; María Guadalupe Zavala-Cerna; Olivia Torres-Bugarín

    2016-01-01

    Feminization of the agricultural labor is common in Mexico; these women and their families are vulnerable to several health risks including genotoxicity. Previous papers have presented contradictory information with respect to indirect exposure to pesticides and DNA damage. We aimed to evaluate the genotoxic effect in buccal mucosa from female farmers and children, working in the agricultural valley of Maneadero, Baja California. Frequencies of micronucleated cells (MNc) and nuclear abnormali...

  9. Characterisation of an enamelled metallic object found in Guerrero Negro (Baja California) by PIXE and RBS techniques

    International Nuclear Information System (INIS)

    Calvo del Castillo, H.; Ruvalcaba, J.L.; Calderon, T.; Salinas Nolasco, M.F.; Mejia, L.M.; Perdigon, K.

    2008-01-01

    The coast of Guerrero Negro (Baja California) has been known for a long time by archaeologists for its shipwrecks. Archaeologists are recovering objects that come from sunken Spanish galleons in the colonial period, and reach the American coast in the frontier of the USA with Mexico. An enamelled metallic object was found next to the beach in Guerrero Negro. We have analysed the piece with proton induced X-ray emission (PIXE) and Rutherford backscattering (RBS) in an attempt to establish whether the object could come from one of the colonial shipwrecks and to valuate its cleaning process. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) have been also performed in three samples taken from the object in order to observe the heterogeneity of the material. The materials found revealed the presence of typical lead-glass enamels from with pigments such as cuprite (red), or lead-tin yellow used in colonial times. The metallic part consisted of brass. As for the cleaning process, the average efficiency considered as the weight% of chlorine removed, was of 83.4% for brass and 100% for enamels

  10. Polychlorinated biphenyls and biotransformation enzymes in three species of sea turtles from the Baja California peninsula of Mexico.

    Science.gov (United States)

    Richardson, K L; Lopez Castro, M; Gardner, S C; Schlenk, D

    2010-01-01

    Concentrations of polychlorinated biphenyls (PCBs) as well as the expression patterns of cytochrome P450 (CYP) enzymes and glutathione-S-transferase (GST) activities were measured in livers of loggerhead (Caretta caretta), green (Chelonia mydas), and olive ridley (Lepidocheyls olivacea) sea turtles from the Baja California peninsula of Mexico. The mean concentrations of total PCBs were 18.1, 10.5, and 15.2 ng/g wet weight (ww) respectively for the three species and PCB 153 was the dominant congener in all samples. Total PCB concentrations were dominated by penta- and hexa-chlorinated biphenyls. The mean estimated TEQs were 42.8, 22.9, and 10.4 pg/g (ww) for loggerhead, green, and olive ridley, respectively, and more than 70% was accounted for by non-ortho PCBs. Western blots revealed the presence of hepatic microsomal proteins that cross-reacted with anti-CYP2K1 and anti-CYP3A27 antibodies but not with anti-CYP1A antibody. There were no significant differences in GST activities between species. Grouping congeners based on structure-activity relationships for CYP isoenzymes suggested limited activity of CYP1A contribution to PCB biotransformation in sea turtles. These results suggest potential accumulation of PCBs that are CYP1A substrates and provide evidence for biotransformation capacity, which differs from known animal models, highlighting the need for further studies in reptiles, particularly those threatened with extinction.

  11. Problemáticas del comportamiento sexual y reproductivo de las jóvenes inmigrantes de Baja California

    Directory of Open Access Journals (Sweden)

    Humberto González Galbán

    2013-01-01

    Full Text Available Entre los aspectos que son analizados en el presente artículo se encuentran los vinculados a la sexualidad y la reproducción de las mujeres inmigrantes de Baja California, donde se manifiestan inequidades con relación al resto de los jóvenes, tales como las mayores afecta- ciones por enfermedades de transmisión sexual y los más altos niveles de embarazos –gene- ralmente no planificados–, lo que a su vez tiene implicaciones como una mayor frecuencia del abandono escolar, la salida involuntaria del hogar paterno así como otras problemáticas familiares, todo lo que incide negativamente en la salud de las jóvenes migrantes y en sus condiciones de vida en general. La atención médica, que puede contribuir a atenuar efec- tos no deseados de dicha situación, también es recibida en menor medida por las jóvenes inmigrantes, lo que conjuntamente con las desventajosas condiciones socioeconómicas en que viven y/o el contar, en un menor grado, con redes familiares y sociales de apoyo, las convierte en una población más vulnerable y necesitada de trabajo comunitario que atienda sus problemáticas sexuales y reproductivas.

  12. Comparative analysis of the reproductive strategy of lion's paw scallop Nodipecten subnodosus in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Marco A Angel-Dapa

    2015-07-01

    Full Text Available The reproductive strategy of lion's paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahía Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and December-March. A continuous breeding is also reported for the species in Bahía Magdalena, Bahía Juncalito, and Bahía de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C, or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahía Tortugas appears beneficial for a continuous reproduction of N. subnodosus.

  13. Vegetation history along the eastern, desert escarpment of the Sierra San Pedro Mártir, Baja California, Mexico

    Science.gov (United States)

    Holmgren, Camille A.; Betancourt, Julio L.; Rylander, Kate A.

    2011-01-01

    Plant macrofossils from 38 packrat middens spanning the last ~ 33,000 cal yr BP record vegetation between ~ 650 and 900 m elevation along the eastern escarpment of the Sierra San Pedro Mártir, northern Baja California. The middens span most of the Holocene, with a gap between ~ 4600 and 1800 cal yr BP, but coverage in the Pleistocene is uneven with a larger hiatus between 23,100 and 14,400 cal yr BP. The midden flora is relatively stable from the Pleistocene to Holocene. Exceptions include Pinus californiarum, Juniperus californica and other chaparral elements that were most abundant > 23,100 cal yr BP and declined after 14,400 cal yr BP. Despite being near the chaparral/woodland-desertscrub ecotone during glacial times, the midden assemblages reflect none of the climatic reversals evident in the glacial or marine record, and this is corroborated by a nearby semi-continuous pollen stratigraphy from lake sediments. Regular appearance of C4 grasses and summer-flowering annuals since 13,600 cal yr BP indicates occurrence of summer rainfall equivalent to modern (JAS average of ~ 80–90 mm). This casts doubt on the claim, based on temperature proxies from marine sediments in the Guaymas Basin, that monsoonal development in the northern Gulf and Arizona was delayed until after 6200 cal yr BP.

  14. Diagnóstico socioambiental como fundamento para una estrategia de educación ambiental en Colonet, Baja California

    Directory of Open Access Journals (Sweden)

    Rosa Hidemi Ortega Armenta

    2012-01-01

    Full Text Available Colonet, Baja California, es una comunidad rural localizada en una zona árida, donde existe la propuesta de construir un megaproyecto portuario. Ahí se realizó un diagnóstico socioambiental, con el fin de identificar la problemática actual del medio ambiente y posibles soluciones, a través del análisis de la percepción social y las amenazas ambientales. El desabasto de agua se percibe como el problema principal debido a factores sociales y políticos, y las prácticas agrícolas se identificaron como la amenaza ambiental primordial. Estos resultados demuestran la necesidad de mejorar la organización comunitaria, con base en mayor y mejor información. Se identificaron las soluciones y se diseñaron cuatro escenarios. Aquí se propone una estrategia de educación ambiental, que fomente la organización y participación informada en la comunidad, para lograr la tecnificación agrícola orgánica y la gestión integrada de recursos hídricos.

  15. Marine diet and tobacco exposure affects mercury concentrations in pregnant women (I from Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Ramón Gaxiola-Robles

    2014-01-01

    Full Text Available Seafood provides essential polyunsaturated fatty acids (PUFA and other nutrients to pregnant women and their fetus(es while a diet rich in finfish can be a major pathway of monomethyl mercury (MeHg+ exposure. We measured total mercury concentration ([THg] in hair samples provided by 75 women in Baja California Sur (BCS to assess its relationship with age, parity, tobacco smoke exposure, and diet based on survey methodologies. Generalized linear models (GLM were used to explain the possible association of the different variables with [THg] in hair. Median [THg] in hair was 1.52 μg g−1, ranging from 0.12 to 24.19 μg g−1 and varied significantly by segment. Approximately 72% (54/75 of those evaluated exceed 1 μg g−1 [THg] and 8% (6/75 exceed 5 μg g−1 [THg] in hair. Although frequency of fish consumption contributed significantly to explaining hair [THg], fish consumption only explained 43% of [THg] in a GLM incorporating tobacco exposure and body mass index. This study establishes possible relationships among multiple potential sources of exposure and other factors related to [THg] in hair of women in the prenatal period. A more detailed examination of other sources of exposure and factors contributing to [THg] is warranted.

  16. The distribution and behaviour of 230Th and 231 Pa at an ocean margin, Baja California, Mexico

    International Nuclear Information System (INIS)

    Shimmield, G.B.; Price, N.B.; Bacon, M.P.; Anderson, R.F.

    1986-01-01

    Uranium, Th and Pa isotopes were measured in sediments collected by box core along a transect normal to the Baja California continental margin. Six cores were analysed, ranging in depositional environment from manganese nodule-bearing, pelagic, red clay to hemipelagic sediments displaying Mn reduction in the upper 5 cm. In the hemipelagic cores, solid-phase Mn peaks due to diagenetic remobilisation occur within the upper layers which are well mixed with respect to unsupported 230 Th and 231 Pa. The fact that 230 Th and 231 Pa are not concentrated at the Mn peaks suggests that little mobility of these nuclides occurs within the sediment column. Unsupported 230 Th/ 231 Pa activity ratios in the biomixed layer of the sediments range from 10.9 to 6.6, generally decreasing towards the inshore stations. The flux of 230 Th and 231 Pa across the sediment/water interface is almost in balance with the theoretical water column supply in the most distal core, but rapidly increases inshore. This evidence from the sediment column confirms that enhanced 230 Th and 231 Pa removal occurs at ocean margins, and that 231 Pa is removed from the water column to the sediments in preference to 230 Th. (author)

  17. La competitividad de los partidos políticos en Baja California en las elecciones de 1997

    Directory of Open Access Journals (Sweden)

    Leopoldo Martínez Herrera

    1997-02-01

    Full Text Available In Mexico, the dernocratic transition, as a strategy for the polilical change, has gained a high effectiveness, also the parties have had so submit themeselves to the evaluation of the citizens due to the recuperation of the liberty of society's conscience. Under the above circunstances, the electoral-political competition, once it is a method to measure the capability of effectiveness and of dispute of the politicqal parties in the actual circunstances, it is also a condition for therir act within a modern, democratic and equal electoral system. An illustrative case is Baja California, that on July 6, 1997, elected six representatives for the House of Representatives of the Nation. The result of this event is presented in this article openly bye the measure of the competition of the parties involved by the following indicators: a simple competition, bmargin of victory between PAN in relation to PRI, cthe power of the opposing party, dnumber of political parties, and eexpansion of the electoral system.

  18. Characterisation of an enamelled metallic object found in Guerrero Negro (Baja California) by PIXE and RBS techniques

    Energy Technology Data Exchange (ETDEWEB)

    Calvo del Castillo, H. [Departamento de Geologia y Geoquimica, Universidad Autonoma de Madrid (Spain); Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico); Centre Europeen d' Archeometrie - I.P.N.A.S., Universite de Liege, Allee du 6 Aout, 10 Bat-15, Sart Tilman, 4000-Liege 1 (Belgium)], E-mail: hcalvo@ulg.ac.be; Ruvalcaba, J.L. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico); Calderon, T. [Departamento de Geologia y Geoquimica, Universidad Autonoma de Madrid (Spain); Salinas Nolasco, M.F. [Coordinacion de Conservacion del Patrimonio Cultural, Instituto Nacional de Antropologia e Historia (Mexico); Mejia, L.M. [Direccion de Arqueologia Subacuatica, Instituto Nacional de Antropologia e Historia (Mexico); Perdigon, K. [Coordinacion de Conservacion del Patrimonio Cultural, Instituto Nacional de Antropologia e Historia (Mexico)

    2008-05-15

    The coast of Guerrero Negro (Baja California) has been known for a long time by archaeologists for its shipwrecks. Archaeologists are recovering objects that come from sunken Spanish galleons in the colonial period, and reach the American coast in the frontier of the USA with Mexico. An enamelled metallic object was found next to the beach in Guerrero Negro. We have analysed the piece with proton induced X-ray emission (PIXE) and Rutherford backscattering (RBS) in an attempt to establish whether the object could come from one of the colonial shipwrecks and to valuate its cleaning process. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) have been also performed in three samples taken from the object in order to observe the heterogeneity of the material. The materials found revealed the presence of typical lead-glass enamels from with pigments such as cuprite (red), or lead-tin yellow used in colonial times. The metallic part consisted of brass. As for the cleaning process, the average efficiency considered as the weight% of chlorine removed, was of 83.4% for brass and 100% for ename0008.

  19. Baseline heavy metals and metalloid values in blood of loggerhead turtles (Caretta caretta) from Baja California Sur, Mexico.

    Science.gov (United States)

    Ley-Quiñónez, C; Zavala-Norzagaray, A A; Espinosa-Carreón, T L; Peckham, H; Marquez-Herrera, C; Campos-Villegas, L; Aguirre, A A

    2011-09-01

    Environmental pollution due to heavy metals is having an increased impact on marine wildlife accentuated by anthropogenic changes in the planet including overfishing, agricultural runoff and marine emerging infectious diseases. Sea turtles are considered sentinels of ecological health in marine ecosystems. The objective of this study was to determine baseline concentrations of zinc, cadmium, copper, nickel, selenium, manganese, mercury and lead in blood of 22 clinically healthy, loggerhead turtles (Caretta caretta), captured for several reasons in Puerto López Mateos, Baja California Sur, Mexico. Zinc was the most prevalent metal in blood (41.89 μg g⁻¹), followed by Selenium (10.92 μg g⁻¹). The mean concentration of toxic metal Cadmium was 6.12 μg g⁻¹ and 1.01μg g⁻¹ respectively. Mean concentrations of metals followed this pattern: Zn>Se>Ni>Cu>Mn>Cd>Pb and Hg. We can conclude that blood is an excellent tissue to measure in relatively non-invasive way baseline values of heavy metals in Caretta caretta. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Valoración socioambiental de los recursos naturales: el caso de los recursos minerales en la parte central de Baja California Sur, México

    OpenAIRE

    Luis F. Beltrán Morales; Víctor Sevilla Unda; Macià Blázquez Salom; Federico Salinas Zavala; Felipe García Rodrígez

    2005-01-01

    Se seleccionaron 15 localidades ubicadas en el radio de influencia de dos depósitos evaluados de fosfato, esto con la finalidad de aplicar el método de valoración contingente del recurso y su medio ambiente: el depósito de Tembabichi en el margen del Golfo de California y el depósito de Santo Domingo en la costa del Pacífico en Baja California Sur, México. Se encontró una disposición media a pagar por los habitantes del área de estudio de $29.77 pesos mensuales para colaborar con el medio amb...

  1. Analysis of drought and desertification by means of aridity indices and the estimation of water gap in Baja California Sur, Northwest Mexico

    Directory of Open Access Journals (Sweden)

    Enrique Troyo Diéguez

    2013-10-01

    Full Text Available In Baja California Sur (BCS, Mexico, dry-semi warm and warm climates prevail associated to an extreme trend of diurnal temperatures and the environmental dryness. In this State, the maximum summer t exceeds 40° C and the minimum varies from 5 to 12° C, with a minimal for the State of 2° C in winter, at the top of the Sierra de La Laguna; only Los Cabos region has a warm humid climate. Because precipitation in the state is low, oscillating from 310 mm in the southern area of the state to 120 mm per year in the northern portion, predictions and scenarios under climate conditions point to an intensification of droughts. The aim of this work was to carry out a comparative analysis of trends of temperature, precipitation and hydro-environmental aridity among contrasting localities of BCS, by means of the application of Aridity Indexes and the determination of the Standardized Water Gap (BHE, through a numerical scale modification of the De Martonne Index. With the values of temperature and precipitation for the different climate change scenarios for four weather stations, the indicators Hydro Environmental Availability Index (IDHA and Hydro Environmental Drought Index (ISHA were calculated to determine their trend and the consequent BHE, an innovative quantification of wáter deficit, which is proposed in this paper. The máximum value of BHE (10 units, indicating prevalence of drought, is observed from February to June in almost the entire state.

  2. Red de participación institucional en las áreas naturales protegidas de la península de Baja California

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    Nain Martínez

    2015-01-01

    Full Text Available con el análisis de redes sociales se estudió la gobernanza de las áreas naturales protegidas de la península de Baja California, a través de su red de participación de 2007 a 2011, y se encontró que ésta se amplió y diversificó. Además, se presentó un fortalecimiento de la escala de gestión regional y una mayor inclusión de los actores sociales interesados en el uso de los recursos y la conservación ambiental. Sin embargo, el efecto en los participantes sobre la red es diferenciado. Así, mientras las instituciones gubernamentales, los académicos y las organizaciones de la sociedad civil incrementaron su influencia, la participación de los actores comunitarios y privados fue restringida. Es necesario profundizar en la investigación sobre la gobernanza y mejorar los mecanismos de participación.

  3. Can the Adoption of Desalination Technology Lead to Aquifer Preservation? A Case Study of a Sociotechnical Water System in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Jamie McEvoy

    2015-09-01

    Full Text Available There is growing concern about the sustainability of groundwater supplies worldwide. In many regions, desalination—the conversion of saline water to freshwater—is viewed as a way to increase water supplies and reduce pressure on overdrawn aquifers. Using data from reports, articles, interviews, a survey, and a focus group, this paper examines if, and how, the adoption of desalination technology can lead to aquifer preservation in Baja California Sur (BCS, Mexico. The paper outlines existing institutional arrangements (i.e., laws, rules, norms, or organizations surrounding desalination in BCS and concludes that there are currently no effective mechanisms to ensure aquifer preservation. Four mechanisms that could be implemented to improve groundwater management are identified, including: 1 integrated water-and land-use planning; 2 creation of an institute responsible for coordinated and consistent planning; 3 improved groundwater monitoring; and 4 implementation of water conservation measures prior to the adoption of desalination technology. This paper concludes that viewing water technologies, including desalination, as sociotechnical systems—i.e., a set of technological components that are embedded in complex social, political, and economic contexts—has the potential to create a more sustainable human–environment–technology relationship. By assessing desalination technology as a sociotechnical system, this study highlights the need to focus on institutional development and capacity building, especially within local water utilities and urban planning agencies.

  4. Constraints on the rheology of the lower crust in a strike-slip plate boundary: evidence from the San Quintín xenoliths, Baja California, Mexico

    Science.gov (United States)

    van der Werf, Thomas; Chatzaras, Vasileios; Marcel Kriegsman, Leo; Kronenberg, Andreas; Tikoff, Basil; Drury, Martyn R.

    2017-12-01

    The rheology of lower crust and its transient behavior in active strike-slip plate boundaries remain poorly understood. To address this issue, we analyzed a suite of granulite and lherzolite xenoliths from the upper Pleistocene-Holocene San Quintín volcanic field of northern Baja California, Mexico. The San Quintín volcanic field is located 20 km east of the Baja California shear zone, which accommodates the relative movement between the Pacific plate and Baja California microplate. The development of a strong foliation in both the mafic granulites and lherzolites, suggests that a lithospheric-scale shear zone exists beneath the San Quintín volcanic field. Combining microstructural observations, geothermometry, and phase equilibria modeling, we estimated that crystal-plastic deformation took place at temperatures of 750-890 °C and pressures of 400-560 MPa, corresponding to 15-22 km depth. A hot crustal geotherm of 40 ° C km-1 is required to explain the estimated deformation conditions. Infrared spectroscopy shows that plagioclase in the mafic granulites is relatively dry. Microstructures are interpreted to show that deformation in both the uppermost lower crust and upper mantle was accommodated by a combination of dislocation creep and grain-size-sensitive creep. Recrystallized grain size paleopiezometry yields low differential stresses of 12-33 and 17 MPa for plagioclase and olivine, respectively. The lower range of stresses (12-17 MPa) in the mafic granulite and lherzolite xenoliths is interpreted to be associated with transient deformation under decreasing stress conditions, following an event of stress increase. Using flow laws for dry plagioclase, we estimated a low viscosity of 1.1-1.3×1020 Pa ṡ s for the high temperature conditions (890 °C) in the lower crust. Significantly lower viscosities in the range of 1016-1019 Pa ṡ s, were estimated using flow laws for wet plagioclase. The shallow upper mantle has a low viscosity of 5.7×1019 Pa ṡ s

  5. Distribución espacial y temporal de aves playeras (Orden: Charadriiformes en Laguna San Ignacio, Baja California Sur, México Temporal and spatial distribution of shorebirds (Charadriiformes at San Ignacio Lagoon, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Luis Francisco Mendoza

    2013-03-01

    Full Text Available Con la pérdida o degradación de humedales han declinado las poblaciones de algunas especies tales como las aves playeras. En vista de que ha crecido el interés internacional por los estudios ecológicos sobre estas especies, se determinó la abundancia, distribución y riqueza espacio-temporal de las aves playeras en Laguna San Ignacio, Península de Baja California. Se realizaron 12 censos mensuales (octubre 2007-septiembre 2008 en el perímetro interno de la laguna; la cual se dividió en cuatro zonas, dos al norte y dos al sur. Temporalmente las abundancias menores se presentaron en mayo (1 585 aves y las mayores en octubre (47 410. Las especies más abundantes fueron: el picopando canelo (Limosa fedoa; 55% de los registros totales, el playero occidental (Calidris mauri; 23% y el playero pihuiuí (Tringa semipalmata; 10%. Estas especies fueron más abundantes en otoño. El picopando canelo y el playero pihuiuí estabilizaron sus números en invierno y primavera y estuvieron presentes en verano en bajos números, el playero occidental mostró oscilaciones notorias. Se presentan los primeros reportes del playero rojizo del Pacifico (Calidris canutus roselaari para la zona. La riqueza y abundancia estuvieron influenciadas temporal y espacialmente por las aves migratorias. Las mayores abundancias se presentaron al sur de la laguna, probablemente por la disponibilidad del alimento. Los resultados presentes permitieron incluir al área en la Red Hemisférica de Reservas para las Aves Playeras como sitio de importancia internacional.Baja California Peninsula has several wetlands that represent important ecosystems for shorebirds. San Ignacio Lagoon is one of these sites, and supports 10% of the total abundance of shorebirds reported in this Peninsula. Since there is few information about this group in this area, we studied spatial and temporal changes in abundance and distribution of shorebirds in San Ignacio Lagoon. For this, we conducted twelve

  6. First record of Pseudomyicola spinosus in Argopecten ventricosus in Baja California, Mexico.

    Science.gov (United States)

    Cáceres-Martínez, Carlos; Chávez-Villalba, Jorge; Garduño-Méndez, Laura

    2005-06-01

    This is the first record of the copepod Pseudomyicola spinosus in the scallop Argopecten ventricosus in northwestern Mexico, and describes: (1) the known annual prevalence and intensity of this copepod on scallops from culture sites (Gulf of California) and natural populations (Pacific coast), (2) the histopathological effects caused on the soft tissues of scallops, and (3) the relationship between prevalence and intensity records and environmental parameters. The copepod was present throughout the period of investigation, showing similar prevalence and ratio of copepod to scallop patterns in both cultured scallops and wild specimens from natural habitats. Highest prevalence and ratio values were detected in summer-autumn at both sites, probably because scallops showed a weak condition from the combined effects of spawning, reabsorption of residual gametes, and high temperature. The condition index of A. ventricosus showed a significant correlation with the presence of the copepod in Magdalena Bay (-0.67). P. spinosus was observed in the gills of scallops, producing alterations or rupture of filaments, and in the stomach, causing detachment and loss of the epithelium. No relationship between copepod infestation with temperature, salinity, chlorophyll, and seston were found during the investigation. Although P. spinosus was present year-round at both sites, no association between infestation and scallop mortalities was detected.

  7. Nutrient fluxes and net metabolism in a coastal lagoon SW peninsula of Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Cervantes Duarte, R.

    2016-09-01

    Full Text Available Fluxes of nutrients and net metabolism were estimated in coastal lagoon Magdalena Bay using LOICZ biogeochemical model. In situ data were obtained from 14 sites in the lagoon and also from a fixed site in the adjacent ocean area. Intense upwelling (February to July and faint upwelling (August to January were analyzed from monthly time series. The Temperature, nitrite + nitrate, ammonium and phosphate within the lagoon showed significant differences (p<0.05 between the two periods. Salinity (p=0.408 was more homogeneous (no significantly different due to mixing processes. During the intense upwelling period, nutrients increased in and out of the lagoon due to the influence of Transitional Water and Subartic Water transported by the California Current. However, during the faint upwelling, from August to January, the Transition Water and Subtropical Surface Water were predominant. Magdalena Bay showed denitrification processes of throughout the year as it occurred in other semi-arid coastal lagoons. It also showed a net autotrophic metabolism during intense upwelling and heterotrophic metabolism during faint upwelling. Understanding nutrient flows and net metabolism through simple biogeochemical models can provide tools for better management of the coastal zone.

  8. Interannual summer variability in oceanic euphausiid communities off the Baja California western coast during 1998-2008

    Science.gov (United States)

    Parés-Escobar, Fernanda; Lavaniegos, Bertha E.; Ambriz-Arreola, Israel

    2018-01-01

    Euphausiids are a major component of the zooplankton biomass due to their large size, contributing with high carbon content to other trophic levels in the pelagic ecosystem. We analyzed the summer interannual variability in euphausiid species composition based on carbon mass of the Baja California oceanic domain during 1998-2008. Selection of one exclusive season allowed the emphasis of interannual changes in order to research possible biological impacts. During the period 1998-2008 prevailed intense interannual activity, with four El Niño events, two of them (1997-1998 and 2006-2007) with SST anomalies propagating toward the eastern Pacific (EP-El Niño), while the other two (2002-2003 and 2004-2005) had SST anomalies limited to the central Pacific (CP-El Niño). There were also La Niña events in 1998-2000 and 2007-2008. The species with higher biomass contribution off Baja California were Nematoscelis difficilis, Euphausia gibboides, Thysanoessa gregaria, Euphausia eximia, Nyctiphanes simplex, and Euphausia pacifica, with a global geometric mean of 156, 66, 38, 30, 21, and 13 μg C m-3 respectively. N. difficilis and E. pacifica were dominant in the northern area (29.5-32°N), N. difficilis and E. gibboides in the central area (27-29.5°N), and E. eximia dominated in the southern area (24.5-27°N). 1998-2008 biomass anomalies showed a variety of patterns by species with the clearest footprint, in most of the species, during the strong EP-El Niño 1997-1998. CP-El Niño events also left a footprint in the biomass of some species but this was not always by anomalies of the same nature as EP-El Niño. The best examples were N. difficilis and N. simplex, which presented lightly positive anomalies during July 1998 but were strongly negative in the summer of 2003 and 2004. The opposite was observed in E. recurva, with a negative anomaly in July 1998 but positive in 2004 and 2005. The biophysical coupling between the species assemblage and environmental variables

  9. Seasonal diet composition of Fundulus lima (Cyprinodontiformes: Fundulidae in two oasis systems of Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Dinora Acosta Zamorano

    2011-12-01

    Full Text Available Fundulus lima inhabits river drainage systems and is threatened after the introduction of cichlids in the area. To support conservation programs, the spatial and temporal variation of the diet composition of this endangered killifish, was determined in two oasis systems of Baja California Sur, Mexico (San Ignacio and La Purisima river drainages, during rainy and dry seasons. F. lima was captured by using passive and active capture techniques. A total of 192 stomach contents of F. lima was analyzed. The contribution of each prey item in the diet composition was quantified by means of the indices of occurrence frequency (% OF, numerical (%N and volume (%V percentages. The relative importance of each prey item was determined according to the percentage of the Relative Importance Index (%RII. The similarity of the diet was calculated between hydrological basins (populations combined by basin, seasons (rainy versus dry months, sexes and size classes, by using Schoener’s resource overlap index. We used two ecological indices to determine the type of feeding strategy exhibited by the fish: (1 niche breadth of Levins and (2 proportional similarity of Feisinger. Sand was the most abundant item in the stomach content of killifishes from both drainages (39% and 47%, respectively. Diet composition was similar for both drainages (74% as well as among their respective size classes; however, it was different between sexes. In both drainages, F. lima predated mainly on diatom algae, dipterous and trichopteran larvae, and fish scales during the dry season; while it preferred dipterous larvae, filamentous algae and ostracods in the rainy season. A feeding strategy of opportunist type was exhibited by F. lima during the rainy season, changing to specialist type during the dry season. This information will be the basis for future investigations related to the conservation of this endangered species and its habitat. Rev. Biol. Trop. 59 (4: 1669-1678. Epub 2011

  10. Community Based Flood Modeling in Southern and Baja California to Meet End User Needs for Decision-Making

    Science.gov (United States)

    Sanders, B. F.

    2017-12-01

    Flooding of coastal and fluvial systems are the most significant natural hazards facing society, and damages have been escalating for decades globally and in the U.S. Almost all metropolitan areas are exposed to flood risk. The threat from river flooding is especially high in India and China, and coastal cities around the world are threatened by storm surge and rising sea levels. Several trends including rising sea levels, urbanization, deforestation, and rural-to-urban population shifts will increase flood exposure in the future. Flood impacts are escalating despite advances in hazards science and extensive effort to manage risks. The fundamental issue is not that flooding is becoming more severe, even though it is in some places, but rather that societies are become more vulnerable to flood impacts. A critical factor contributing to the escalation of flood impacts is that the most vulnerable sectors of communities are left out of processes to prepare for and respond to flooding. Furthermore, the translation of knowledge about flood hazards and vulnerabilities into actionable information for communities has not been effective. In Southern and Baja California, an interdisciplinary team of researchers has partnered with stakeholders in flood vulnerable communities to co-develop flood hazard information systems designed to meet end-user needs for decision-making. The initiative leveraged the power of advanced, fine-scale hydraulic models of flooding to craft intuitive visualizations of context-sensitive scenarios. This presentation will cover the ways by which the process of flood inundation modeling served as a focal point for knowledge development, as well as the unique visualizations that populate on-line information systems accessible here: http://floodrise.uci.edu/online-flood-hazard-viewers/

  11. Baseline heavy metals and metalloid values in blood of loggerhead turtles (Caretta caretta) from Baja California Sur, Mexico

    International Nuclear Information System (INIS)

    Ley-Quinonez, C.; Zavala-Norzagaray, A.A.; Espinosa-Carreon, T.L.; Peckham, H.; Marquez-Herrera, C.; Campos-Villegas, L.; Aguirre, A.A.

    2011-01-01

    Highlights: → We report baseline levels of selected heavy metals in blood of Pacific loggerhead turtles. → Blood was used to measure in a relatively non-invasive way baseline values of heavy metals. → Zn and Cd were found in high concentrations compared to levels reported in other parts of the world. → Cu concentrations in blood are high as they relate to concentrations in muscle. → No correlations were found between of heavy metals and metalloids analyzed and the size of the turtles. - Abstract: Environmental pollution due to heavy metals is having an increased impact on marine wildlife accentuated by anthropogenic changes in the planet including overfishing, agricultural runoff and marine emerging infectious diseases. Sea turtles are considered sentinels of ecological health in marine ecosystems. The objective of this study was to determine baseline concentrations of zinc, cadmium, copper, nickel, selenium, manganese, mercury and lead in blood of 22 clinically healthy, loggerhead turtles (Caretta caretta), captured for several reasons in Puerto Lopez Mateos, Baja California Sur, Mexico. Zinc was the most prevalent metal in blood (41.89 μg g -1 ), followed by Selenium (10.92 μg g -1 ). The mean concentration of toxic metal Cadmium was 6.12 μg g -1 and 1.01 μg g -1 respectively. Mean concentrations of metals followed this pattern: Zn > Se > Ni > Cu > Mn > Cd > Pb and Hg. We can conclude that blood is an excellent tissue to measure in relatively non-invasive way baseline values of heavy metals in Caretta caretta.

  12. AUV Mapping and ROV Exploration of Los Frailes Submarine Canyon, Cabo Pulmo National Marine Park, Baja California Sur, Mexico

    Science.gov (United States)

    Troni, G.; Caress, D. W.; Graves, D.; Thomas, H. J.; Thompson, D.; Barry, J. P.; Aburto-Oropeza, O.; Johnson, A. F.; Lundsten, L.

    2015-12-01

    Los Frailes submarine canyon is located at the south boundary of the Cabo Pulmo National Marine Park on the southeast tip of the Baja California Peninsula. During the Monterey Bay Aquarium Research Institute (MBARI) 2015 Gulf of California expedition we used an autonomous underwater vehicle (AUV) to map this canyon from 50 m to 450 m depths, and then explored the canyon with a small remotely operated vehicle (ROV). This three day R/V Rachel Carson cruise was a collaboration with the Center for Marine Biodiversity and Conservation at Scripps Institution of Oceanography and the Centro para la Biodiversidad Marina y la Conservación in La Paz. The MBARI AUV D. Allan B. collected high resolution bathymetry, sidescan, and subbottom profiles of Los Frailes submarine canyon and part of the north Cabo Pulmo deep reef. In order to safely generate a 1-m lateral resolution multibeam bathymetry map in the nearshore high relief terrain, the mapping operations consisted of an initial short survey following the 100-m isobath followed by a series of short, incremental AUV missions located on the deep edge of the new AUV bathymetry. The MBARI Mini-ROV was used to explore the submarine canyon within the detailed map created by the MBARI AUV. The Mini-ROV is a 1.2-m-long, 350 kg, 1,500-m-depth-rated ROV designed and constructed by MBARI. It is controlled by six 600-watt thrusters and is equipped with a high-definition video camera and navigation sensors. This small ROV carries less accurate, lower cost navigation sensors than larger vehicles. We implemented new algorithms to localize combining Doppler velocity log sensor data and low-cost MEMS-based inertial sensor data with sporadic ultra-short baseline position measurements to provide a high accuracy position estimation. The navigation performance allowed us to colocate the ROV video imagery with the 1-m resolution bathymetric map of the submarine canyon. Upper Los Frailes Canyon is rugged and, aside from small sand pockets along

  13. Geochemical characteristics of water from the reservoir of the hydrothermal system of Las Tres Virgenes, Baja California Sur, Mexico; Caracteristicas geoquimicas de las aguas del reservorio del sistema hidrotermal actual de Las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gonalez Partida, Eduardo [Universidad Nacional Autonoma de Mexico (Mexico); Tello Hinojosa, Enrique [Comision Federal de Electricidad (Mexico); Pal Verma, Mahendra [Instituto de Investigaciones Electricas (Mexico)

    2001-03-01

    The Las Tres Virgenes geothermal field is a liquid dominated system. The separated produced by the wells are sodium-chloride type, which is a characteristic of totally equilibrated geothermal brine. The temperature of water-rock interaction in the reservoir is 280 Celsius degrees. the chemical composition of gases corresponds to the one expected in a geothermal environment. The CO{sub 2} is the predominating gas and it is superior in 90% in weight to the total of existing gases. The gas contents is less than 1% in weight, in the case of the wells LV-1 and LV-3. It is also possible to conclude that the gases are in equilibrium with the liquid phase at a temperature of 280 Celsius degrees. With respect to water quality, it is saline, from high to very high and the contents of exchangeable sodium is also very high, resulting in waters not fit for agricultural usage. [Spanish] El yacimiento geotermico de Las Tres Virgenes, en Baja California Sur, Mexico, es un sistema de liquido dominante, en donde el agua separada producida por los pozos presenta un caracter clorurado-sodico caracteristico de una salmuera de origen geotermico totalmente equilibrada. El sistema agua-roca se encuentra en equilibrio a una temperatura de 280 grados centigrados , dicha temperatura son congruentes con las estimadas para las fases gaseosas y liquidas. La composicion quimica de los gases corresponde a la esperada en un ambiente geotermico. El CO{sub 2} es el predominante y es superior a 90% en peso del total de los gases presentes. El contenido de gas es menor de 1% en peso en el caso de los pozos LV-1 y LV-3. Tambien se puede concluir que los gases estan en equilibrio en las fases liquidas a una temperatura de 280 grados centigrados. Con respecto a la calidad del agua, presenta una salinidad de alta a muy alta y el contenido de sodio intercambiable tambien es muy alto, por lo que dichas aguas no son muy aptas para el cultivo.

  14. Lithofacies of deep marine basalts emplaced on a Jurassic backarc apron, Baja California (Mexico)

    Energy Technology Data Exchange (ETDEWEB)

    Busby-Spera, C.J.

    1987-09-01

    Basalts of the mid-Jurassic Gran Canon Formation, Cedros Island, Mexico, were emplaced on a volcaniclastic apron in a deep marine backarc basin. Elongate pillows and lava tubes, as well as paleocurrent data from the volcaniclastic apron, indicate a southward regional paleoslope away from the island arc source. Basalts emplaced on relatively proximal parts of the apron are nearly entirely pillowed and have thick flow units with mega-pillows. Basalts on distal parts of the apron (about 15 to 20 km down paleo-current) are dominated by pillow fragment breccias (flow foot rubble), and individual lava flows are generally thin, with small pillows, suggesting that the distal ends of lava flows, erupted upslope, are represented. These distal flow fronts, however, are interstratified with features that typically form close to a vent, including thick massive to mega-pillowed lavas and lava tubes up to 8 m in diameter. It is inferred that a fissure (or system of fissures) extended from the arc into the backarc basin, erupting basalt lavas onto both proximal and distal parts of the volcaniclastic apron. Such intraplate volcanism may be common on the hot frontal arc side of backarc basins. 26 references.

  15. Sedimentary gravity flows from subaerial fan-deltas in Loreto Bay, Baja California Sur, Mexico

    Science.gov (United States)

    Navarro-Lozano, José O.; Nava-Sánchez, Enrique H.; Godínez-Orta, Lucio

    2010-05-01

    Fan-deltas from Loreto Bay show recent evidences of sedimentary gravity flows as a result from catastrophic events during hurricane rainfalls. The knowledge of hydrological characteristics of these flows is important for understanding the effects of storms on fan-deltas geomorphology in this region, as well as for the urban developing planning of the city of Loreto in order to avoid hazardous zones. The analysis of precipitation and hurricane tracks data for the period 1945 to 2009 indicates that hurricanes have caused catastrophic floods every 20 years. Stratigraphy from the channel incision shows a sequence of stream flow and debris flow controlled by changes in the competence and capacity of the stream, which are associated to the gentle slope (<2 °) of the fan-deltas. However fans from the north of the bay (Arce and Gúa) show deposits of debris flows associated to catastrophic floods, which have caused the incision channel to drift towards the southern part of the fans, while flows from Las Parras fan-delta, from the middle of the bay, are dominated by stream flows. These differences in the type of the flows are controlled by lithology, shape and size of the drainage basin, and slope of the transit zone in the feeder channel.

  16. The physicochemical characterization of cave paintings of Baja California; Caracterizacion fisicoquimica de pigmentos y soportes en pinturas murales: caso Mayapan, Yucatan

    Energy Technology Data Exchange (ETDEWEB)

    Valdez, B.; Cobo, J.; Schorr, M. [Area de Corrosion y Materiales, Instituto de Ingenieria, Universidad Autonoma de Baja California, Blvd. Benito Juarez, S/N, 21280, Mexicali, B.C. (Mexico); Cota, L. [Centro de Ciencias de la Materia Condensada, UNAM, Ensenada, B.C. (Mexico); Oviedo, F. [Centro INAH - BC, Ensenada, B.C. (Mexico)]. e-mail: benval@iing.mxl.uabc.mx

    2006-07-01

    The Palaeolithic paintings of Baja California constitute an important contribution to the national, historic and cultural patrimony of Mexico. The aim of this investigation was to determine the physicochemical characteristics, the microstructure and texture of these polychrome paintings, painted on rocks encountered in the mountainous, desert/arid zones of Baja California and Baja California South. The first stage of this work was devoted to the examination and recording of the cave paintings of 'El Vallecito', a narrow fluvial valley displaying large granitic rocks emerging from the sandy soil. Tiny painting samples were collected and analyzed by SEM, EDS and FTIR techniques. The painters used four main colours: red, black, yellow and white. The paint raw materials are mineral pigments: white (kaolin, calcite, and gypsum), red (hematite), yellow (ochre, limonite), black (charcoal from burnt wood or calcined bones) and water as a diluent and/or a binder, all encountered in the painters habitat. The minerals were collected, ground and sometimes heated to change their tone. By mixing with water, a spreadable paste or a thick slurry was produced, which was applied with the fingers for lines or a piece of animal skin for figures, respectively. The 100% solids, dry paint converts into a dense, hard layer, incrusted into the grainy, rough, hollow granite rock surface. This paint might be called {sup s}tone on stone{sup ,} explaining its permanence for centuries enduring heat, wind and weather. A simulation of the painting technique was done at the Materials and Corrosion Laboratory, UABC by collecting mineral pigments, preparing the paint as a paste or slurry and applying it on a granitic rock. Knowing the paint composition, production and application techniques will be useful in e conservation and restoration of cave paintings and stone-built, ancient structures such as pyramids, cathedrals and monuments. (Author)

  17. Prevalencia de sífilis congénita en tres hospitales públicos de Baja California, México, 2012-2015

    OpenAIRE

    Jorge Luis Arellano-Estrada; Cinthia Selene López-Lara; Erendida Barreras-Valenzuela

    2017-01-01

    Señor editor: Presentamos los resultados de un estudio descriptivo con base en datos de estudio epidemiológico (EE) de caso para sífilis congénita (SC). El formato contiene antecedentes, síntomas, evolución y asociación con factores de riesgo (FR) del binomio madre-hijo. El análisis se basa en identificar la prevalencia de SC en los Hospitales de la Secretaría de Salud (SSa) de los municipios de Tijuana, Playas de Rosarito y Tecate, Baja California, de 2012 a 2015.

  18. Prevalencia de sífilis congénita en tres hospitales públicos de Baja California, México, 2012-2015

    Directory of Open Access Journals (Sweden)

    Jorge Luis Arellano-Estrada

    2017-08-01

    Full Text Available Señor editor: Presentamos los resultados de un estudio descriptivo con base en datos de estudio epidemiológico (EE de caso para sífilis congénita (SC. El formato contiene antecedentes, síntomas, evolución y asociación con factores de riesgo (FR del binomio madre-hijo. El análisis se basa en identificar la prevalencia de SC en los Hospitales de la Secretaría de Salud (SSa de los municipios de Tijuana, Playas de Rosarito y Tecate, Baja California, de 2012 a 2015.

  19. Lithospheric strength in the active boundary between the Pacific Plate and Baja California microplate constrained from lower crustal and upper mantle xenoliths

    Science.gov (United States)

    Chatzaras, Vasileios; van der Werf, Thomas; Kriegsman, Leo M.; Kronenberg, Andreas; Tikoff, Basil; Drury, Martyn R.

    2017-04-01

    The lower crust is the most poorly understood of the lithospheric layers in terms of its rheology, particularly at active plate boundaries. We studied naturally deformed lower crustal xenoliths within an active plate boundary, in order to link their microstructures and rheological parameters to the well-defined active tectonic context. The Baja California shear zone (BCSZ), located at the western boundary of the Baja California microplate, comprises the active boundary accommodating the relative motion between the Pacific plate and Baja California microplate. The basalts of the Holocene San Quintin volcanic field carry lower crustal and upper mantle xenoliths, which sample the Baja California microplate lithosphere in the vicinity of the BCSZ. The lower crustal xenoliths range from undeformed gabbros to granoblastic two-pyroxene granulites. Two-pyroxene geothermometry shows that the granulites equilibrated at temperatures of 690-920 oC. Phase equilibria (P-T pseudosections using Perple_X) indicate that symplectites with intergrown pyroxenes, plagioclase, olivine and spinel formed at 3.6-5.4 kbar, following decompression from pressures exceeding 6 kbar. FTIR spectroscopy shows that the water content of plagioclase varies among the analyzed xenoliths; plagioclase is relatively dry in two xenoliths while one xenolith contains hydrated plagioclase grains. Microstructural observations and analysis of the crystallographic texture provide evidence for deformation of plagioclase by a combination of dislocation creep and grain boundary sliding. To constrain the strength of the lower crust and upper mantle near the BCSZ we estimated the differential stress using plagioclase and olivine grain size paleopiezomtery, respectively. Differential stress estimates for plagioclase range from 10 to 32 MPa and for olivine are 30 MPa. Thus the active microplate boundary records elevated crustal temperatures, heterogeneous levels of hydration, and low strength in both the lower crust and

  20. Unraveling the channel–lobe transition zone with high-resolution AUV bathymetry: Navy Fan, offshore Baja California, Mexico

    Science.gov (United States)

    Carvajal, Cristian; Paull, Charles K.; Caress, David W.; Fildani, Andrea; Lundsten, Eve M.; Anderson, Krystle; Maier, Katherine L.; McGann, Mary; Gwiazda, Roberto; Herguera, Juan Carlos

    2017-01-01

    Ultra-high-resolution (1 m * 1 m * 0.25 m) bathymetry was acquired with an autonomous underwater vehicle (AUV) over a sector of the Navy Fan offshore Baja California. The survey specifically targeted an area where the former interpretation of the fan showed a channel–lobe transition; however, the lobe and the transition were not recognized. Instead, the newly acquired bathymetry shows that the previously identified channel continues basinward changing its overall morphology and stratigraphic architecture, becoming gradually but significantly wider (650–1000 m) and of lower relief (3–4 m). Cores from the channel thalweg recovered mud-poor (< 5%) well-sorted sands, interpreted as deposited by fully turbulent flows. The cores also show several mud-rich (9–18%) poorly sorted sands, probably indicating deposition from more cohesive flows.The high-resolution bathymetry shows large sectors of the seafloor sculpted by elaborate bedforms and scours. The overbank area north of the channel exhibits the most numerous and prominent scours, interpreted to have been largely generated by flow stripping at a bend in the channel. Along high-gradient sectors (more than approximately 1¯) of this area, the scours are largest and deepest. Some of these scours show an erosional headwall and a distal upflow-dipping depositional bulge, forming repetitive bedforms interpreted as erosional cyclic steps associated with locked-in-place trains of hydraulic jumps. The scours seem to coalesce to form an incipient channel, which would likely drive the avulsion of the main channel. Further basinward, average gradients decrease (< 0.6¯ ) and scours become smaller and less deep suggesting a gradient control on erosion. The southern channel margin and adjacent overbank area exhibit a trend of scours that are elongated transverse to flow, that successively repeat themselves basinwards, and that at times merge with sediment waves. Probably these scours are genetically linked to sediment waves

  1. Cestodes of the blue shark, Prionace glauca (Linnaeus 1758), (Carcharhiniformes: Carcharhinidae), off the west coast of Baja California Sur, Mexico.

    Science.gov (United States)

    Méndez, Oscar; Galván-Magaña, Felipe

    2016-03-03

    The cestode species recovered from the spiral intestines of 27 blue sharks (Prionace glauca) (Linnaeus, 1758) are reported from the western coast of Baja California Sur (BCS). The sampling was undertaken on a monthly basis from January 2003 to January 2004. The helminthological examination indicated the presence of four species of cestodes: Platybothrium auriculatum Yamaguti, 1952; Prosobothrium japonicum Yamaguti, 1934; Anthobothrium caseyi (Yamaguti, 1934) Ruhnke & Caira, 2009; and Paraorygmatobothrium prionacis (Yamaguti, 1934) Ruhnke, 1994. Of all the 27 sharks examined, 88.8% were infected with at least one cestode species. The most frequent species was P. auriculatum infecting 85% of the spiral intestines examined. In contrast the species with the highest mean intensity was P. prionacis (80.4 200). The species richness of cestodes in P. glauca is very similar in other regions of the world despite its wide distribution; however, this richness is low compared with other species of sharks within the same family. The feeding and host-specific are important factors that influence the parameters of infection of cestodes in this shark. On the west coast of BCS, Prionace glauca feeds mainly on red crab Pleuroncodes planipes Stimpson, 1860; squids Gonatus californiensis Young, 1972, Ancistrocheirus lesueurii (D'Orbigny, 1842), Haliphron atlanticus Steenstrup, 1861, and low proportion of fish teleosts as Merluccius productus (Ayres, 1855), Sardinops sp. Hubbs, 1929 and Scomber japonicus Houttuyn, 1872. We speculate that these prey could be involved as the second intermediate hosts of these cestodes, as in other members of these genera, although the life cycles of none are known.

  2. Results and evaluation of the first study of organochlorine contaminants (PCDDs, PCDFs, PCBs and DDTs), heavy metals and metalloids in birds from Baja California, Mexico

    International Nuclear Information System (INIS)

    Jimenez, Begona; Rodriguez-Estrella, Ricardo; Merino, Ruben; Gomez, Gema; Rivera, Laura; Jose Gonzalez, Maria; Abad, Esteban; Rivera, Josep

    2005-01-01

    Organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p-p'-DDE), heavy metals (Pb, Cd, Zn, Cu), and arsenic were measured in house sparrows (Passer domesticus) and common ground doves (Columbina passerina) from Baja California Sur, Mexico. Concentrations of PCDD/Fs were low, with 21 pg/g for house sparrows, and 7.7 pg/g for common ground doves. Non-ortho-PCB concentrations in house sparrow and common ground doves were 58 and 254 pg/g, respectively, and are within the highest concentrations reported in species that are in the low levels of food webs. The major differences in organochlorine levels between species were found for ortho-PCBs and DDTs. ortho-PCB levels were higher in the seedeater species, whereas DDT levels were higher in the omnivorous species. Heavy metal levels were far below those associated with negative effects. - Capsule: The first data on contaminants in birds from Baja California is given

  3. Results and evaluation of the first study of organochlorine contaminants (PCDDs, PCDFs, PCBs and DDTs), heavy metals and metalloids in birds from Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Begona [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)]. E-mail: bjimenez@iqog.csic.es; Rodriguez-Estrella, Ricardo [Centro de Investigaciones Biologicas del Noroeste, Mar Bermejo 195, Apdo. Postal 128, La Paz, Baja California Sur (Mexico); Merino, Ruben [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Gomez, Gema [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Rivera, Laura [Centro de Investigaciones Biologicas del Noroeste, Mar Bermejo 195, Apdo. Postal 128, La Paz, Baja California Sur (Mexico); Jose Gonzalez, Maria [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Abad, Esteban [Department of Ecotechnologies, Research and Development Center, CSIC, Jordi Girona, 18-26, 08034 Barcelona (Spain); Rivera, Josep [Department of Ecotechnologies, Research and Development Center, CSIC, Jordi Girona, 18-26, 08034 Barcelona (Spain)

    2005-01-01

    Organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p-p'-DDE), heavy metals (Pb, Cd, Zn, Cu), and arsenic were measured in house sparrows (Passer domesticus) and common ground doves (Columbina passerina) from Baja California Sur, Mexico. Concentrations of PCDD/Fs were low, with 21 pg/g for house sparrows, and 7.7 pg/g for common ground doves. Non-ortho-PCB concentrations in house sparrow and common ground doves were 58 and 254 pg/g, respectively, and are within the highest concentrations reported in species that are in the low levels of food webs. The major differences in organochlorine levels between species were found for ortho-PCBs and DDTs. ortho-PCB levels were higher in the seedeater species, whereas DDT levels were higher in the omnivorous species. Heavy metal levels were far below those associated with negative effects. - Capsule: The first data on contaminants in birds from Baja California is given.

  4. La dinámica territorial de las principales instituciones bancarias en la península de Baja California: estructura e interrelaciones

    Directory of Open Access Journals (Sweden)

    Lilia Susana Padilla Sotelo

    2001-03-01

    Full Text Available This research analyzes the territorial distribution of the main banking institutions within the Baja California peninsula´s urban space. It starts by providing a background on the spatial organization of banking institutions in the study area and their relationship within the national context, stressing their borderline location. The location-focused analysis, through examining the territorial distribution of the 158 bank offices from the seven main Institutions, allows to detect a considerable concentration in small and mid-sized urban towns located to the north. Also, banks tend to be located at the most populated towns having differential behaviors. Since this aspect is related to the economic activity that takes place in them, these towns have become preferential spaces, resulting in territorial unbalances. The cities of Tijuana and Mexicali stand out, followed to a lesser extent by La Paz and Ensenada, The territorial distribution of banking institutions in Baja California follows the same behavior pattern as the one that occurs at a national level, i.e. location according to the specific area of specialty.

  5. Characterization of emissions sources in the California-Mexico Border Region during Cal-Mex 2010

    Science.gov (United States)

    Zavala, M. A.; Lei, W.; Li, G.; Bei, N.; Barrera, H.; Tejeda, D.; Molina, L. T.; Cal-Mex 2010 Emissions Team

    2010-12-01

    The California-Mexico border region provides an opportunity to evaluate the characteristics of the emission processes in rapidly expanding urban areas where intensive international trade and commerce activities occur. Intense anthropogenic activities, biomass burning, as well as biological and geological sources significantly contribute to high concentration levels of particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), nitrogen oxides (NOx), volatile organic compounds (VOCs), air toxics, and ozone observed in the California-US Baja California-Mexico border region. The continued efforts by Mexico and US for improving and updating the emissions inventories in the sister cities of San Diego-Tijuana and Calexico-Mexicali has helped to understand the emission processes in the border region. In addition, the recent Cal-Mex 2010 field campaign included a series of measurements aimed at characterizing the emissions from major sources in the California-Mexico border region. In this work we will present our analyzes of the data obtained during Cal-Mex 2010 for the characterization of the emission sources and their use for the evaluation of the recent emissions inventories for the Mexican cities of Tijuana and Mexicali. The developed emissions inventories will be implemented in concurrent air quality modeling efforts for understanding the physical and chemical transformations of air pollutants in the California-Mexico border region and their impacts.

  6. Cadmium and phosphate variability during algal blooms of the dinoflagellate Lingulodinium polyedrum in Todos Santos Bay, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez-Mejia, E. [Posgrado en Oceanografía Costera, Instituto de Investigaciones Oceanológicas/Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Campus Sauzal, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Ensenada, Baja California CP 22860 (Mexico); Lares, M.L., E-mail: llares@cicese.mx [División de Oceanología, Departamento de Oceanografía Biológica, Centro de Investigación Científica y de Educación Superior de Ensenada, Km 107 Carretera Transpeninsular Ensenada-Tijuana, Ensenada, Baja California CP 22880 (Mexico); Huerta-Diaz, M.A.; Delgadillo-Hinojosa, F. [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Sauzal, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Ensenada, Baja California CP 22860 (Mexico)

    2016-01-15

    Dinoflagellate algal blooms (DABs), with Lingulodinium polyedrum as the dominant species, have increased over the past few years in coastal areas off Baja California, Mexico. Vertical and temporal variability of particulate cadmium (Cd{sub p}), dissolved Cd (Cd{sub d}), PO{sub 4}{sup 3−} and Cd{sub d}/PO{sub 4}{sup 3−} were investigated during two intense DABs of L. polyedrum that occurred during the fall of 2011 and 2012 in Todos Santos Bay. Results were then, compared with data gathered in the absence of algal blooms during the autumn of 2013. In both algal blooms, L. polyedrum tended to be concentrated near the surface throughout the duration; however, during DAB 2011 the number of cells was twice as abundant ([10.0 ± 8.0] × 10{sup 5} cells L{sup −1}) as in DAB 2012 ([5.0 ± 4.4] × 10{sup 5} cells L{sup −1}). During DAB 2011, Cd{sub p} increased significantly (up to 1.02 ± 0.99 nmol kg{sup −1}) and was positively correlated with the cell abundance of L. polyedrum, suggesting that this dinoflagellate is able to assimilate and concentrate Cd{sub d}. Likewise, Cd{sub d} (up to 0.71 ± 0.17 nM) increased in the days of highest cell abundance, which could be attributed to uptake and subsequent regeneration of Cd{sub d} resulting from the remineralization of organic particulate matter produced during the bloom, as well as with the presence of organic ligands secreted by L. polyedrum that could keep Cd{sub d} in solution. During DAB 2011, dissolved Cd{sub d}/PO{sub 4}{sup 3−} ratios exhibited high vertical and temporal variability in the upper 5 m of the water column, but remained virtually constant near the bottom, suggesting a depth-dependent decoupling between these two dissolved components during the bloom development. Given the observed differences in the vertical and temporal variability of Cd{sub d}, Cd{sub p}, and PO{sub 4}{sup 3−} between these two intense DABs, we propose the existence of an abundance threshold of approximately 10{sup 6

  7. Cadmium and phosphate variability during algal blooms of the dinoflagellate Lingulodinium polyedrum in Todos Santos Bay, Baja California, Mexico

    International Nuclear Information System (INIS)

    Gutierrez-Mejia, E.; Lares, M.L.; Huerta-Diaz, M.A.; Delgadillo-Hinojosa, F.

    2016-01-01

    Dinoflagellate algal blooms (DABs), with Lingulodinium polyedrum as the dominant species, have increased over the past few years in coastal areas off Baja California, Mexico. Vertical and temporal variability of particulate cadmium (Cd_p), dissolved Cd (Cd_d), PO_4"3"− and Cd_d/PO_4"3"− were investigated during two intense DABs of L. polyedrum that occurred during the fall of 2011 and 2012 in Todos Santos Bay. Results were then, compared with data gathered in the absence of algal blooms during the autumn of 2013. In both algal blooms, L. polyedrum tended to be concentrated near the surface throughout the duration; however, during DAB 2011 the number of cells was twice as abundant ([10.0 ± 8.0] × 10"5 cells L"−"1) as in DAB 2012 ([5.0 ± 4.4] × 10"5 cells L"−"1). During DAB 2011, Cd_p increased significantly (up to 1.02 ± 0.99 nmol kg"−"1) and was positively correlated with the cell abundance of L. polyedrum, suggesting that this dinoflagellate is able to assimilate and concentrate Cd_d. Likewise, Cd_d (up to 0.71 ± 0.17 nM) increased in the days of highest cell abundance, which could be attributed to uptake and subsequent regeneration of Cd_d resulting from the remineralization of organic particulate matter produced during the bloom, as well as with the presence of organic ligands secreted by L. polyedrum that could keep Cd_d in solution. During DAB 2011, dissolved Cd_d/PO_4"3"− ratios exhibited high vertical and temporal variability in the upper 5 m of the water column, but remained virtually constant near the bottom, suggesting a depth-dependent decoupling between these two dissolved components during the bloom development. Given the observed differences in the vertical and temporal variability of Cd_d, Cd_p, and PO_4"3"− between these two intense DABs, we propose the existence of an abundance threshold of approximately 10"6 cells L"−"1 of L. polyedrum above which Cd and PO_4"3"− significantly increased due to remineralization in coastal

  8. Diálogo de saberes ambientales entre Europa-América. Agroecosistemas oasianos en Baja California Sur s. XVIII-XX

    Directory of Open Access Journals (Sweden)

    Ortega Santos, Antonio

    2015-06-01

    Full Text Available During two centuries, Oasis Communities of Baja California had been living in a intense connection with their environment. With the arrival of Jesuits, a deep extermination of biocultural heritage and socioenvironmental knowledges of these communities, repopulating of vegetable garden and drylands with people –in many cases, settler from the south of Spain- reconstructing the territorial identity as ranchera to manage the ecosystems under pattern of self-competence and under-consumption, due to the strong environmental constraints of lower california agro-ecosystem. At the beginning of XXIth century, Oasis Communities are fighting against the loss of community heritage, embedded in Eden with enormous bio-cultural dimension, rescuing and keeping crops from Europe with the Jesuits arrival. This frame allow us to draw a colonization process of ecosystems during contemporary age.Desde hace más de dos siglos, las Comunidades Oasianas de Baja California Sur han estado viviendo en íntima conexión con su medio ambiente. Con la llegada de los Jesuitas se produjo un intenso proceso de exterminio biocultural de los saberes sociambientales de esas comunidades, repoblando estas huertas y llanos con población -en muchos casos colonos- procedentes del sur de España-, redimensionado la identidad territorial como ranchera que gestionó los ecosistemas bajo pautas de autosuficiencia y subconsumo, dadas las fuertes constricciones socioambientales de agroecosistemas sudcalifornianos. A inicios del siglo XXI, las comunidades oasianas luchan contra la pérdida de sus saberes comunitarios, enclavados en edenes de enorme potencial biocultural, rescatando y manteniendo los cultivos traídos con la llegada de los jesuitas. Este marco nos permite describir un proceso de colonización de los ecosistemas a lo largo de los dos últimos siglos.

  9. Estudio de algunos procesos pedogenéticos en el valle de Ojos Negros, Baja California, México

    Directory of Open Access Journals (Sweden)

    Francisco Raúl Venegas Cardoso

    2012-02-01

    Los procesos de erosión, transporte y acumulación de materiales en las tierras bajas continúan a la fecha, asimismo, la presencia de un proceso relativamente reciente: materiales que están siendo redistribuidos por el viento y depositados sobre diques de metarriolita, provocado por las condiciones de sequía en toda la región.

  10. El papel de los comités Pro-Estado en la creación del estado de Baja California

    Directory of Open Access Journals (Sweden)

    Lawrence Douglas Taylor

    1999-01-01

    Full Text Available El artículo trata del papel de los Comités Pro-Estado en la formación de Baja California como estado. Se analizan las raíces de la autonomía política en la península, que se remontan al Porfiriato, así como el impacto de la Revolución Mexicana sobre este proceso. Se examinan los diversos movimientos pro- estado que surgieron de 1929 en adelante la composición de sus grupos de integrantes, sus objetivos y contribuciones principales en términos de dirigir el sentimiento popular hacia la realización de esta meta.

  11. El impacto de las tecnologías de la información y comunicación en la industria manufacturera de Baja California

    Directory of Open Access Journals (Sweden)

    Lourdes Alicia González Torres

    2017-04-01

    Full Text Available En este artículo se analizó el comportamiento de la adopción de las tecnologías de la información y comunicación en los subsectores manufactureros de Baja California, para determinar sus efectos en los resultados económicos y los cambios que generan en las empresas. Para ello se utilizaron seis dimensiones del modelo desarrollado por Karmarkar y Mangal (2004, y con la tau-b de Kendall se calculó la correlación entre el grado de adopción de dichas tecnologías y los resultados económicos. Aunque éstos no se compararon con los de otros estudios, puesto que aquí sólo se seleccionó cierto tipo de empresas, se logró exponer la situación del sector manufacturero estatal, en relación con el uso de las tecnologías. Por lo que se puede concluir que la adopción de éstas influye positivamente en los resultados de las empresas. ________________________ This paper analyzes the performance of the adoption of information and communication technologies in manufacturing sub-sectors of Baja California in order to determine their effects on the economic results and the changes generated in the companies. For this purpose, six dimensions of the model developed by Karmarkar and Mangal (2004 were utilized, and using the Kendall’s tau-b the correlation between the level of adoption of such technologies and the economic results was calculated. Although these were not compared to those of other studies, since only certain types of companies were selected, the situation of state manufacturing sector was set out in relation to the use of these technologies. Therefore, it can be concluded that the adoption of such technologies has a positive influence on the performance of companies.

  12. Lunar phase and catch success of the striped marlin (Tetrapturus audax in sport fishing at Los Cabos, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    G. Ponce-Díaz

    2003-06-01

    Full Text Available The influence of the lunar phases on the catch-per-unit effort (CPUE of the striped marlin (Tetrapturus audax captured by the Cabo San Lucas, Baja California Sur, Mexico sport-fishing fleet from October 1987 to June 1989 was analyzed. The information is from 3 377 fishing trips by 13 vessels that represent about 10 % of the fleet. The analysis of the CPUE showed a maximum in January 1988 and a minimum in February 1989. Taking into account the knowledge of the factors that had influence on the fishing success is important in the resource management. No significant difference during the full moon compared with results during other lunar phases was found.Se analizó la influencia de las fases lunares sobre la captura por unidad de esfuerzo en el marlín rayado (Tetraptus audax capturado por la flota deportiva en Cabo San Lucas, Baja California Sur, desde octubre de 1987 a junio de 1989. La información de 3377 viajes de pesca por 13 embarcaciones que representan cerca de un 10% de la flota. El análisis mostró un máximo en enero de 1988 y un mínimo en febrero de 1989. Tomar en consideración el conocimiento de los factores que tuvieron influencia en el éxito en la pesca es importante en el manejo de los recursos. No se encontró diferencias significativas durante la luna llena comparado con los resultados obtenidos durante las otras fases de la luna.

  13. Baseline study of morphometric traits of wild Capsicum annuum growing near two biosphere reserves in the Peninsula of Baja California for future conservation management.

    Science.gov (United States)

    Murillo-Amador, Bernardo; Rueda-Puente, Edgar Omar; Troyo-Diéguez, Enrique; Córdoba-Matson, Miguel Víctor; Hernández-Montiel, Luis Guillermo; Nieto-Garibay, Alejandra

    2015-05-10

    Despite the ecological and socioeconomic importance of wild Capsicum annuum L., few investigations have been carried out to study basic characteristics. The peninsula of Baja California has a unique characteristic that it provides a high degree of isolation for the development of unique highly diverse endemic populations. The objective of this study was to evaluate for the first time the growth type, associated vegetation, morphometric traits in plants, in fruits and mineral content of roots, stems and leaves of three wild populations of Capsicum in Baja California, Mexico, near biosphere reserves. The results showed that the majority of plants of wild Capsicum annuum have a shrub growth type and were associated with communities consisting of 43 species of 20 families the most representative being Fabaceae, Cactaceae and Euphorbiaceae. Significant differences between populations were found in plant height, main stem diameter, beginning of canopy, leaf area, leaf average and maximum width, stems and roots dry weights. Coverage, leaf length and dry weight did not show differences. Potassium, sodium and zinc showed significant differences between populations in their roots, stems and leaves, while magnesium and manganese showed significant differences only in roots and stems, iron in stems and leaves, calcium in roots and leaves and phosphorus did not show differences. Average fruit weight, length, 100 fruits dry weight, 100 fruits pulp dry weight and pulp/seeds ratio showed significant differences between populations, while fruit number, average fruit fresh weight, peduncle length, fruit width, seeds per fruit and seed dry weight, did not show differences. We concluded that this study of traits of wild Capsicum, provides useful information of morphometric variation between wild populations that will be of value for future decision processes involved in the management and preservation of germplasm and genetic resources.

  14. Valoración socioambiental de los recursos naturales: el caso de los recursos minerales en la parte central de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Luis F. Beltrán Morales

    2012-02-01

    Full Text Available Se seleccionaron 15 localidades ubicadas en el radio de influencia de dos depósitos evaluados de fosfato, esto con la finalidad de aplicar el método de valoración contingente del recurso y su medio ambiente: el depósito de Tembabichi en el margen del Golfo de California y el depósito de Santo Domingo en la costa del Pacífico en Baja California Sur, México. Se encontró una disposición media a pagar por los habitantes del área de estudio de $29.77 pesos mensuales para colaborar con el medio ambiente de su región. Hipotéticamente se daría una valoración contingente en el total del área de estudio de $227 859.58 pesos mensuales, es decir, $2 734 314.9 pesos anuales. Es una cantidad considerable de recursos para contribuir a mejoras en el medio ambiente por comunidades rurales con signos de marginación socioeconómica.

  15. Placental biomarkers of PAH exposure and glutathione-S-transferase biotransformation enzymes in an obstetric population from Tijuana, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dodd-Butera, Teresa, E-mail: tdbutera@csusb.edu [California State University San Bernardino, Department of Nursing, 5500 University Parkway, San Bernardino, CA 92407 (United States); San Diego State University, Graduate School of Public Health, San Diego, CA (United States); Union Institute & University, Cincinnati, OH (United States); Quintana, Penelope J.E., E-mail: jquintan@mail.sdsu.edu [San Diego State University, Graduate School of Public Health, San Diego, CA (United States); Ramirez-Zetina, Martha, E-mail: martharz8@hotmail.com [Instituto Mexicano del Seguro Social Tijuana, BC (Mexico); Batista-Castro, Ana C., E-mail: anabatista101@hotmail.com [Instituto Mexicano del Seguro Social Tijuana, BC (Mexico); Hospital General de Tijuana, Tijuana (Mexico); Sierra, Maria M., E-mail: sierramer@gmail.com [San Diego State University, Graduate School of Public Health, San Diego, CA (United States); Shaputnic, Carolyn, E-mail: cshaputnic@ucsd.edu [San Diego State University, Graduate School of Public Health, San Diego, CA (United States); University of California, San Diego, Western FASD Practice and Implementation Center, Department of Pediatrics, Division of Dysmorphology-Teratology, San Diego, CA (United States); Garcia-Castillo, Maura, E-mail: mauragarcia@gmail.com [Xochicalco Universidad Escuela de Medicina, BC (Mexico); Institute for Public Health, San Diego State University, San Diego, CA (United States); Ingmanson, Sonja, E-mail: sonejah@yahoo.com [San Diego State University, Graduate School of Public Health, San Diego, CA (United States); Hull, Stacy, E-mail: hulst74@hotmail.com [San Diego State University, Graduate School of Public Health, San Diego, CA (United States)

    2017-01-15

    Environmental exposures along the US-Mexico border have the potential to adversely affect the maternal-fetal environment. The purpose of this study was to assess placental biomarkers of environmental exposures in an obstetric population at the California-Baja California border in relation to detoxifying enzymes in the placenta and nutritional status. This study was conducted on consenting, full-term, obstetric patients (n=54), delivering in a hospital in Tijuana, Baja California (BC), Mexico. Placental polyaromatic hydrocarbon (PAH)-DNA adducts were measured in addition to placental glutathione-S-transferase (GST) activity and genotype, maternal serum folate, and maternal and umbilical cord blood lead and cadmium levels. A questionnaire was administered to the mothers to determine maternal occupation in a maquiladora, other exposures, and obstetric indicators. In univariate analysis, maternal serum folate levels were inversely correlated with total PAH-DNA adducts (rho=−0.375, p=0.007); adduct #1 (rho=−0.388, p=0.005); and adduct #3 (rho =−0.430, p=0.002). Maternal lead levels were significantly positively correlated with cord blood lead levels (rho=0.512, p<0.001). Cadmium levels were generally very low but significantly higher in mothers exposed to environmental tobacco smoke (ETS) (either at work or at home, n=10). In multivariate analysis, only maternal serum folate levels remained as a significant negative predictor of total DNA-PAH adducts levels in placenta. These findings affirm that placental tissue is a valuable and readily available source of human tissue for biomonitoring; and indicate that further study of the role of nutrition in detoxification and mitigation of environmental exposures in pregnant women is warranted. - Highlights: • Maternal-fetal environment susceptible to toxic exposures at US-Mexico border. • Lower serum folate was correlated with higher PAH-DNA adduct levels at birth. • Placental DNA adducts in GST mu (-) cord blood

  16. Placental biomarkers of PAH exposure and glutathione-S-transferase biotransformation enzymes in an obstetric population from Tijuana, Baja California, Mexico

    International Nuclear Information System (INIS)

    Dodd-Butera, Teresa; Quintana, Penelope J.E.; Ramirez-Zetina, Martha; Batista-Castro, Ana C.; Sierra, Maria M.; Shaputnic, Carolyn; Garcia-Castillo, Maura; Ingmanson, Sonja; Hull, Stacy

    2017-01-01

    Environmental exposures along the US-Mexico border have the potential to adversely affect the maternal-fetal environment. The purpose of this study was to assess placental biomarkers of environmental exposures in an obstetric population at the California-Baja California border in relation to detoxifying enzymes in the placenta and nutritional status. This study was conducted on consenting, full-term, obstetric patients (n=54), delivering in a hospital in Tijuana, Baja California (BC), Mexico. Placental polyaromatic hydrocarbon (PAH)-DNA adducts were measured in addition to placental glutathione-S-transferase (GST) activity and genotype, maternal serum folate, and maternal and umbilical cord blood lead and cadmium levels. A questionnaire was administered to the mothers to determine maternal occupation in a maquiladora, other exposures, and obstetric indicators. In univariate analysis, maternal serum folate levels were inversely correlated with total PAH-DNA adducts (rho=−0.375, p=0.007); adduct #1 (rho=−0.388, p=0.005); and adduct #3 (rho =−0.430, p=0.002). Maternal lead levels were significantly positively correlated with cord blood lead levels (rho=0.512, p<0.001). Cadmium levels were generally very low but significantly higher in mothers exposed to environmental tobacco smoke (ETS) (either at work or at home, n=10). In multivariate analysis, only maternal serum folate levels remained as a significant negative predictor of total DNA-PAH adducts levels in placenta. These findings affirm that placental tissue is a valuable and readily available source of human tissue for biomonitoring; and indicate that further study of the role of nutrition in detoxification and mitigation of environmental exposures in pregnant women is warranted. - Highlights: • Maternal-fetal environment susceptible to toxic exposures at US-Mexico border. • Lower serum folate was correlated with higher PAH-DNA adduct levels at birth. • Placental DNA adducts in GST mu (-) cord blood

  17. Capacidades institucionales y desempeño de los organismos operadores de agua en Hermosillo, Sonora, y Mexicali, Baja California

    Directory of Open Access Journals (Sweden)

    Edmundo Loera Burnes

    2017-01-01

    Full Text Available Con el enfoque de capacidad institucional, aquí se analizan los factores políticos que influyeron en la asignación de recursos jurídicos, organizacionales y humanos para la Comisión Estatal de Servicios Públicos de Mexicali y para Agua de Hermosillo. También cómo influye el titular del Ejecutivo en su operación, y cómo se refleja la influencia de los factores institucionales en su desempeño. Si bien el estudio muestra la baja capacidad de ambos organismos en el aspecto de recursos humanos, el de Mexicali es superior en los otros rubros, y eso se traduce en más planeación y, por lo tanto, en mejor desempeño.

  18. Southern California Regional Technology Acceleration Program

    Energy Technology Data Exchange (ETDEWEB)

    Ochoa, Rosibel [Univ. of California, San Diego, CA (United States). Jacobs School of Engineering; Rasochova, Lada [Univ. of California, San Diego, CA (United States). Rady School of Management

    2014-09-30

    UC San Diego and San Diego State University are partnering to address these deficiencies in the renewable energy space in the greater San Diego region, accelerating the movement of clean energy innovation from the university laboratory into the marketplace, building on the proven model of the William J. von Liebig Center’s (vLC’s) Proof of Concept (POC) program and virtualizing the effort to enable a more inclusive environment for energy innovation and expansion of the number of clean energy start-ups and/or technology licenses in greater California.

  19. Using Drone Imagery and Photogrammetry to Map Basin Stratigraphy and Structures Exposed in Mine, Road, and Arroyo Outcrops, Santa Rosalia, Baja California Sur, Mexico

    Science.gov (United States)

    Banes, A.; Alvarez Ortega, K. G.; Henry, M.; Niemi, T.

    2017-12-01

    During the 2017 Baja Basins Research Experience for Undergraduates (REU), a DJI Phantom 3 Advanced Quadcopter drone equipped with a GPS-enabled, 12 Megapixel camera was manually flown to collect aerial photographs of several geologic outcrops on the Minera Boléo and Lucifer mines in central Baja California Sur. The strip mine faces, roadcuts, and arroyos exposed Neogene to Quaternary sediments of the Santa Rosalía basin including the basal Cu-Zn-Mn-Co-bearing Miocene Boléo Formation that is actively being mined. It is overlain by Plio-Quaternary marine and non-marine deposits. Photographs were collected with a 70% overlap and processed into geographically-referenced, orthophotomosaics using Agisoft Photoscan. The output models have an adequate resolution for viewing bedding and fault characteristics. Measurements can be made inside the 3D models, making drones a useful tool for studying the geometry of stratigraphic, structural, and geomorphologic features. The studied sites included: 1) roadcuts on Mesa Soledad that exposed oblique-slip faults and syntectonically deposited non-marine and marine conglomerates and sandy, fossil-rich Pliocene beach sediment; 2) outcrops of the Boléo Fm in the Texcoco mine area that showed the detailed stratigraphic relationship between ore seams (mantos) and faults; 3) outcrops where sandstone samples were collected for detrital zircon geochronology; 4) strip mine 3120 that exposed faults and folds in the Boléo Formation; and 5) faults in Miocene volcanic rocks in the Arroyo Infierno near the Lucifer mine. This study shows that photogrammetry and modeling of geologic structures exposed in mine and road outcrops can provide useful information for reconstructing basin architecture and clarifying structural evolution of the Santa Rosalia Basin.

  20. Crecimiento y mortalidad de la madreperla Pinctada mazatlanica en poblaciones naturales del litoral oriental de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Humberto Wright-López

    2009-06-01

    Full Text Available La madreperla Pinctada mazatlanica esta en veda desde 1939 y considerada en peligro de extinción, cambiando su categoría a protección especial en 1994. El presente estudio estima su crecimiento y mortalidad en bancos naturales en el periodo 1992-93 y 1997-99. Se registró el alto de la concha de ostras en poblaciones desde el paralelo 28º a 23º LN del litoral oriental de Baja California Sur, abarcando 38 estaciones, 2 bahías y 6 islas. La longitud máxima estimada fue 187.22mm (179.83-195.81mm, P > 0.95. Las frecuencias de longitud se ordenaron en un "año virtual". Los parámetros de crecimiento de von Bertalanffy estimados con el programa ELEFAN I fueron: o = 193.31mm, k=0.54año-1, t0= -0.1805 años, C=0.49 y WP=0.75; el índice de desempeño del crecimiento fue’=4.305. La mortalidad total fue de Z=2.03 año-1 por longitud convertida a curva de captura. La regresión peso total y la altura tuvo la expresión W(i=0.0005418 * L(i2.7301. Los parámetros de crecimiento fueron similares a los de Pinctada margaritifera de bancos de mar abierto y diferentes a aquellos de ostras perleras en repoblamiento en bahía de La Paz. La mortalidad mostró valores parecidos a los estimados para Pinctada radiata del Mar Rojo.Growth and mortality of the mother-of-pearl Pinctada mazatlanica in natural populations of the east coast of Baja California Sur, Mexico. The Mexican Pacific mother-of-pearl Pinctada mazatlanica was placed in forbidden fisheries status for the Mexican Federal Government and considered in extinction danger since 1939. This decree was modified in 1994 to allow the capture of spat for research or marine culture. We estimated the growth and mortality of mother-of-pearl from the eastern littoral of South Baja California wild stock in the periods 1992-93 and 1997-99. We used 38 sample stations at 2 bays and 6 insular complexes. The maximum length was 187.22 mm (179.83-195.81 mm, P > 0.95. Seasonal von Bertalanffy growth (ELEFAN I routine

  1. Status of the peregrine falcon in the Rocky Mountains and the southwestern United States, Baja California, and Mexico (south of Texas)

    Science.gov (United States)

    Porter, Ron; Craig, G.R.; Ellis, D.H.; Enderson, J.H.; Hunt, W.G.; Schaeffer, Philip P.; Ehlers, Sharyn M.

    1978-01-01

    About 31 pairs of peregrines still nest north of Mexico, from Idaho and Montana south through West Texas, New Mexico and Arizona. At least thirty-six additional pairs nest in Mexico. Although the nesting sites are occupied, the tissues of the peregrine?s prey species still contain high concentrations of pesticides. The eggs in some Rocky Mountain eyries have shells which are precariously thin and have high residue levels of DDE in their contents. Increasing economic development is encroaching on the peregrine habitat throughout its range in western North America. In Baja California. and Mexico south of Texas this involves increased agricultural activity including use of organochlorine pesticides, increased tourism and increased use of the Gulf of California both for commercial and sport fishing, with their potential disturbance of eyrie sites and reduction of the peregrine?s aquatic feeding prey base. As the fish in the Gulf decrease in number, some of the avian species on which peregrines prey will likewise decrease. This ultimately may effect the peregrine. These factors may have been involved in the demise of the peregrine on Baja California?s Pacific coast. Furthermore, throughout its range, residential, industrial, mining, geothermal, recreational and other types of development and land use practices sometimes destroy habitat essential to the survival of the peregrine. A recent request for the protection of an historical site in California as Critical Habitat under Section 7 of the Endangered Species Act was rejected because peregrines, although observed there, were not known to have produced eggs or young at the site for several decades. With inadequate protection of abandoned, but still suitable, historical eyrie sites, the peregrine may have an insufficient number of eyries to reoccupy in recovery attempts. The lack of present occupancy of a site, without biological evidence that the site is no longer suitable for reoccupancy, is insufficient cause to give

  2. Estructura de tallas y edad del marlin rayado Tetrapturus audax (Pisces:Xiphidae,en Cabo San Lucas,Baja California Sur,México

    Directory of Open Access Journals (Sweden)

    Felipe Neri Melo Barrera

    2004-12-01

    Full Text Available De 1988 a 1993 se muestrearon 1030 ejemplares de marlin rayado (Tetrapturus audax capturados por la flota deportiva de Cabo San Lucas.Se recolectaron 389 espinas dorsales para la estimación de la edad.La relación Longitud mandibular-Radio total de la espina es similar para hembras y machos.Se encontró que la cuarta espina dorsal refleja adecuadamente el crecimiento.La periodicidad de formación de las marcas de crecimiento es anual y parece que se relaciona con la temperatura superficial promedio del mar.Se contaron las bandas opaco-hialinas en cada corte de las espinas,y se encontraron diez grupos de edad (del dos al once,siendo el grupo siete el más abundante, seguido por los grupos seis y ocho.Las tallas observadas para el marlin rayado fueron de 160-280 cm de longitud mandibular,el 90%de los organismos estuvieron entre 190 y 225 cm.Los ejemplares pequeños se incorporan a la pesquería de junio hasta diciembre.Size and age structure of the striped marlin Tetrapturus audax (Pisces:Xiphidae,at Cabo San Lucas,Baja California Sur,México .The striped marlin (Tetrapturus audaxis found in temperate and tropical waters of the Pacific and Indian Ocean.It is particularly abundant in the southern tip of the Baja California peninsula.Specimens brought to Cabo San Lucas port (22 °53 ’ N y 109 °54 ’ Wby the sport fishery fleet that operates withing a radius of 54 km from 1988 to 1993 were sexes,measured and weighed.A total 1030 individuals were sampled.Dorsal fin spines (389were collected for age estimation.The spines were sectioned and hyaline-opaque bands counted.The relation of length to spine radius was similar for males and females.The fourth dorsal spine reflected the growth of the fish.The rhythm of growth mark formation is yearly and related to the sea surface temperature.Ten age groups were found and the seventh group was the most abundant,followed by groups "6 "and "8 ".The age structure of the striped marlin was stable in the study

  3. Evaluation of criteria of environmental fitness for popular houses of the low income sector to arid regions in Mexicali, Baja California; Evaluacion de criterios de adecuacion ambiental para la vivienda popular de sectores de bajos ingresos al clima calido extremo de Mexicali, B.C.

    Energy Technology Data Exchange (ETDEWEB)

    Corral Martinez, Maria [Universidad Autonoma de Baja California, Mexicali, Baja California (Mexico)

    2000-07-01

    The main purpose of this work is to present the impact on minimizing thermal loads, the traditional bioclimatic criteria commonly utilized on low income housing types in Mexicali, B.C., Mexico by showing the results of dynamic thermal evaluation based in the DOE 2.1e software as well as its technical description, with the purpose of providing recommendations for low income popular houses on arid regions, due to the high reduction percentages that can be obtained during summertime. Therefore, having the data obtained from the field as a starting point, the thermal problematic in popular housing is detected. A properties is chosen from a representative range of government supported housing types named progressive housing which are offered an financially available to the large low income popular sector in order to determine the thermal environmental function using the DOE 2.1e software and a gnomon analysis. To conclude evaluations showed that by integrating and applying traditional thermal and environmental strategies that are commonly used in this region, it is possible to reduce as much 50% of the annual cooling internal load, enhancing thermal comfort conditions in natural bioclimatic way. [Spanish] El objetivo de este trabajo es mostrar el impacto en la reduccion de la carga interna de enfriamiento, de los criterios de adecuacion ambiental que tradicionalmente se aplican en la vivienda de Mexicali, B.C., Mexico presentando los resultados de una evaluacion termica en estado dinamico con el programa DOE 2.1e y la descripcion tecnica de las mismas, con el proposito de hacer recomendaciones para la vivienda popular de bajos ingresos en zonas aridas. Para ello a partir de informacion de campo se detecta la existencia de problema termico en la vivienda popular. Se revisa un prototipo representativo de los programas oficiales de vivienda ofrecido a los sectores populares denominado vivienda progresiva, a fin de establecer el grado de adecuacion termico ambiental con el

  4. Interdisciplinary approach on evaluation and sustainable usage of the water resources in the semi-arid Northwest Mexico to counter the imbalance of water: Case study Valle de Guadalupe, Baja California

    Science.gov (United States)

    Kretzschmar, T.; Hernandez, R.; Valenzuela, C.; Cabello, A.

    2012-12-01

    use and 5) water reuse to counter the hydrologic imbalance. The cultivation of the vine is largely governed by the water availability from precipitation. Water stress caused by annual rainfall lower than 350 mm produces a decrease in photosynthetic activity. This stress reduces growth and affects the balance between sugar concentration, organic acids and pH leading to a reduced productivity. The average annual rainfall for Ensenada, Baja California is 285 mm which requires additional water supply for the vines. Although the water has become a scarce resource and the growing conflicts in water availability in Baja California, there are very few studies assessing the water needs of this plant in the region. The groundwater extraction in the study area result in a significant hydrologic imbalance with a deficit of up to 20 Mm3y-1 with significant fluctuation in groundwater recharge estimates ranging from 5 Mm3y-1 to up to over 50 Mmy-1 depending on the annual precipitation. Detailed studies including the establishment of a recharge field laboratory are going on to precise these values and to be able to counter the present imbalance of water to reach sustainable water availability in the basins in coming decades.

  5. Sierra San Pedro Mártir, Baja California, cool-season precipitation reconstructed from earlywood width of Abies concolor tree rings

    Science.gov (United States)

    Meko, D. M.; Touchan, R.; Díaz, J. Villanueva; Griffin, D.; Woodhouse, C. A.; Castro, C. L.; Carillo, C.; Leavitt, S. W.

    2013-12-01

    Tree ring data are analyzed for a multicentury record of drought history in the Sierra San Pedro Mártir (SSPM) of Baja California, Mexico. Climatic variation in the study area is of particular interest because the SSPM is a rich biotic environment at the southern limit of the California floristic province and the southern limit of the planetary jet stream. Future shifts in the jet stream would be expected to have amplified effect on this marginal environment. The study applies linear regression to tree ring indices of earlywood-width of Abies concolor to estimate a 353 year (1658-2010 C.E.) record of cool-season (October-April) precipitation, P, in SSPM. Time-nested regression models account for more than half the variance of grid point P in calibration periods of length 50-65 years. Cross-spectral analysis indicates strong tracking of observed P by the reconstruction over a broad range of frequencies. Robustness of the reconstruction is supported by synchrony of reconstructed P with tree ring variations in other tree species from SSPM. The reconstruction emphasizes the severity of the 1950s drought in a long-term context and the single-year intensity of droughts in the last decade: 2007 stands out as the driest reconstructed year, with a high percentage of missing rings in A. concolor. The reconstruction identifies the early twentieth century pluvial as the wettest epoch in the last 353 years in the SSPM. High-elevation tree species in SSPM may be especially well-suited to sensing snowpack-related moisture variations associated with a southerly branched jet stream and the types of weather systems active in the pluvial.

  6. Interacciones de pesquerías ribereñas en Bahía Magdalena-Almejas, Baja California Sur

    Directory of Open Access Journals (Sweden)

    Miguel A. Ojeda Ruiz de la Peña

    2012-01-01

    Full Text Available Con el fin de aportar al desarrollo de un modelo conceptual sobre la pesca ribereña o artesanal en el área de Bahía Magdalena-Almejas, Baja California Sur, se jerarquizó la importancia de 14 pesquerías de la región. La calificación se basó en un análisis cualitativo por puntos y en la estimación de un índice de importancia relativa, con indicadores como los promedios de captura, valor y frecuencia de registro de especies objetivo en desembarcos de embarcaciones menores, de 1998 a 2009; entre ellas están: almeja catarina, escama, camarón, callo de hacha, tiburón, jaiba, calamar, almeja pata de mula, rayas, lisa, pulpo, abulón, langosta y caracol chino. La interacción temporal entre varias de ellas es controlada por vedas oficiales, pero cuando ocurre se reconocen posibles efectos por pesca incidental e ilegal y modificaciones al ecosistema.

  7. Violencia laboral intramuros. Hostigamiento sexual y otras formas de violencia contra la mujer en las maquiladoras de Sonora y Baja California

    Directory of Open Access Journals (Sweden)

    Mireya Scarone Adarga

    2014-01-01

    Full Text Available El objetivo del presente artículo es identificar los comportamientos en torno al hostigamiento sexual y otras formas de violencia contra la mujer en el ámbito laboral de la maquiladora en los estados de Sonora y Baja California. Para analizar dichas conductas se requirió de herramientas de la metodología cualitativa, como las entrevistas semiestructuradas y grupos focales, que se les hicieron durante 2012 a 31 trabajadoras de maquiladoras de las entidades mencionadas. En los relatos se identificó la violencia psicológica, física, económica, sexual, verbal y simbólica. Se encontró una asociación entre expresiones de diversas formas de violencia laboral y el hostigamiento sexual con la organización del trabajo y la estructura laboral de la maquiladora, que es clave para comprender la subordinación y desvalorización del trabajo femenino en este sector.

  8. Cadmium concentration in liver and muscle of silky shark (Carcharhinus falciformis) in the tip of Baja California south, México

    International Nuclear Information System (INIS)

    Terrazas-López, Rafael; Arreola-Mendoza, Laura; Galván-Magaña, Felipe; Anguiano-Zamora, Marlene; Sujitha, S.B.; Jonathan, M.P.

    2016-01-01

    Cadmium concentrations were determined in the tissues of muscle and liver of Carcharhinus falciformis (silky shark) sampled in Todos Santos, Baja California South, Mexico. This is one of the main shark species for human consumption in Mexico. Results indicate that accumulation of Cd varied in both sexes, based on its metabolism, sex, maturity and other biological characteristics. High Cd values were observed in the liver of adults of male (529.61 μg g −1 ) and female (457.43 μg g −1 ), whereas, in muscular tissues it was low (0.37 μg g −1 ) than the prescribed permissible limits for seafood (0.5 μg g −1 ). Substantial correlations were observed between body length and Cd values in adults except young male due to faster growth rate and its metabolism. The study indicated the impact of environmental conditions in the accumulation of Cd and its risk to the food web structure in the marine environment and health hazard for humans. - Highlights: •Cadmium in liver and muscle of silky shark, Mexico. •Accumulation is based on its metabolism, sex, maturity and biological characteristics. •Health hazard for humans and it is a risk to the food web structure.

  9. Biomonitoring with Micronuclei Test in Buccal Cells of Female Farmers and Children Exposed to Pesticides of Maneadero Agricultural Valley, Baja California, Mexico.

    Science.gov (United States)

    Castañeda-Yslas, Idalia Jazmin; Arellano-García, María Evarista; García-Zarate, Marco Antonio; Ruíz-Ruíz, Balam; Zavala-Cerna, María Guadalupe; Torres-Bugarín, Olivia

    2016-01-01

    Feminization of the agricultural labor is common in Mexico; these women and their families are vulnerable to several health risks including genotoxicity. Previous papers have presented contradictory information with respect to indirect exposure to pesticides and DNA damage. We aimed to evaluate the genotoxic effect in buccal mucosa from female farmers and children, working in the agricultural valley of Maneadero, Baja California. Frequencies of micronucleated cells (MNc) and nuclear abnormalities (NA) in 2000 cells were obtained from the buccal mucosa of the study population (n = 144), divided in four groups: (1) farmers (n = 37), (2) unexposed (n = 35), (3) farmers' children (n = 34), and (4) unexposed children (n = 38). We compared frequencies of MNc and NA and fitted generalized linear models to investigate the interaction between these variables and exposition to pesticides. Differences were found between farmers and unexposed women in MNc (p < 0.0001), CC (p = 0.3376), and PN (p < 0.0001). With respect to exposed children, we found higher significant frequencies in MNc (p < 0.0001), LN (p < 0.0001), CC (p < 0.0001), and PN (p < 0.004) when compared to unexposed children. Therefore working as a farmer is a risk for genotoxic damage; more importantly indirectly exposed children were found to have genotoxic damage, which is of concern, since it could aid in future disturbances of their health.

  10. Biomonitoring with Micronuclei Test in Buccal Cells of Female Farmers and Children Exposed to Pesticides of Maneadero Agricultural Valley, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Idalia Jazmin Castañeda-Yslas

    2016-01-01

    Full Text Available Feminization of the agricultural labor is common in Mexico; these women and their families are vulnerable to several health risks including genotoxicity. Previous papers have presented contradictory information with respect to indirect exposure to pesticides and DNA damage. We aimed to evaluate the genotoxic effect in buccal mucosa from female farmers and children, working in the agricultural valley of Maneadero, Baja California. Frequencies of micronucleated cells (MNc and nuclear abnormalities (NA in 2000 cells were obtained from the buccal mucosa of the study population (n=144, divided in four groups: (1 farmers (n=37, (2 unexposed (n=35, (3 farmers’ children (n=34, and (4 unexposed children (n=38. We compared frequencies of MNc and NA and fitted generalized linear models to investigate the interaction between these variables and exposition to pesticides. Differences were found between farmers and unexposed women in MNc (p<0.0001, CC (p=0.3376, and PN (p<0.0001. With respect to exposed children, we found higher significant frequencies in MNc (p<0.0001, LN (p<0.0001, CC (p<0.0001, and PN (p<0.004 when compared to unexposed children. Therefore working as a farmer is a risk for genotoxic damage; more importantly indirectly exposed children were found to have genotoxic damage, which is of concern, since it could aid in future disturbances of their health.

  11. Lack of knowledge about mother-to-child HIV transmission prevention in pregnant women at Tijuana General Hospital, Baja California, Mexico.

    Science.gov (United States)

    Becka, Chandra M; Chacón-Cruz, Enrique; Araneta, Maria Rosario; Viani, Rolando M

    2015-01-01

    The objective of this study was to identify determinants of human immunodeficiency virus (HIV) knowledge regarding mother-to-child transmission (MTCT) among pregnant women at Tijuana General Hospital, Baja California, Mexico. Between March and November 2003, patients from the prenatal care (n = 1294) and labor and delivery (L&D) units (n = 495) participated in a cross-sectional study to measure HIV knowledge. Less than one-third (30%) knew that HIV could be transmitted to a child during delivery, and 36% knew that HIV could be transmitted by breast-feeding. Only 27% knew that an MTCT could be prevented. Prenatal patients were more likely to know that MTCT was preventable (prenatal: 31% versus L&D 25%; P = .02). Logistic regression indicated that prenatal patients (odds ratio = 1.49, confidence interval 1.07-2.07) were more likely to know that HIV could be transmitted through breast-feeding. Overall, both groups had poor knowledge regarding MTCT of HIV. © The Author(s) 2014.

  12. Long-term change in eelgrass distribution at Bahía San Quintín, Baja California, Mexico, using satellite imagery

    Science.gov (United States)

    Ward, David H.; Morton, Alexandra; Tibbitts, T. Lee; Douglas, David C.; Carrera-Gonzalez, Eduardo

    2003-01-01

    Seagrasses are critically important components of many marine coastal and estuarine ecosystems, but are declining worldwide. Spatial change in distribution of eelgrass, Zostera marina L., was assessed at Bahía San Quintín, Baja California, Mexico, using a map to map comparison of data interpreted from a 1987 Satellite Pour l'Observation de la Terre multispectral satellite image and a 2000 Landsat Enhanced Thematic Mapping image. Eelgrass comprised 49% and 43% of the areal extent of the bay in 1987 and 2000, respectively. Spatial extent of eelgrass was 13% less (-321 ha) in 2000 than in 1987 with most losses occurring in subtidal areas. Over the 13-yr study period, there was a 34% loss of submerged eelgrass (-457 ha) and a 13% (+136 ha) gain of intertidal eelgrass. Within the two types of intertidal eelgrass, the patchy cover class (turbidity caused by a single flooding event in winter of 1992-1993. Recent large-scale agricultural development of adjacent uplands may have exacerbated the effects of the flood. Oyster farming was not associated with any detectable losses in eelgrass spatial extent, despite the increase in number of oyster racks from 57 to 484 over the study period.

  13. Th, Pa and U isotopes in an echinoderm, Encope grandis. An application to dating of some fossil samples from Southern Baja California

    Energy Technology Data Exchange (ETDEWEB)

    Omura, A [Kanazawa Univ. (Japan). Faculty of Science; Ku, T

    1979-03-01

    The application of /sup 230/Th and /sup 231/Pa growth methods to the hard tissues of living things, which are effective for the radiometric age measurement for latter Quaternary period, has been limited to certain corals, therefore it has been scarcely utilized in other areas than coral reefs. Reef coral fossils (Porites) were obtained from terrace deposits of Magdalena Island in Southern Baja California, and the methods were applied to them. At the time, the isotope compositions of Th, Pa and U in the shells of echinoderm Encope Grandis and of the living samples were examined. The estimated ages were in agreement with those of coral. It suggests that the reliable /sup 230/Th and /sup 231/Pa ages of sea-urchin fossils were presented for the first time and that the method is applicable to such fossils only if the conditions can be met. The results are highly significant, since the method may be used in other areas than coral reefs. (J.P.N.).

  14. The Cooperativism and Agricultural Credit in Baja California, Mexico (1930-1950: A first approach El cooperativismo y la financiación agrícola en Baja California, México (1930-1950: Una aproximación inicial

    Directory of Open Access Journals (Sweden)

    Jesús Méndez Reyes

    2011-01-01

    Full Text Available In order to the neoclassic conventional theory the operation of the credit markets face two basic difficulties: the asymmetric or imperfect information and the adverse selection of the borrower come together with the nonpayment risk. On and other side, more heterodox, the collectivism, the social capital and the creation of informal nets and credit societies, use to low down the transaction costs related to the financing problem. This kind of organization makes easier the development of cooperativism in economy. In México, after the Revolution and the establishment of an authoritarian political and vertical regimen, the cooperativism became one of the referents of the rural organization in order to get credit of private and public banks. In the northeast of the country and Baja California peninsula, the existence of fishing, cattle raising, farming and transportation cooperatives means a blunt of economical activity and one of the channels of development in the zone. The purpose of this article is to shape what kind of cooperativism was set up in the Northern District of Baja California and what type of relation kept with the national cooperative movement between 1930 and 1950.Para la teoría neoclásica convencional el funcionamiento de los mercados de crédito soporta dos dificultades básicas: la información imperfecta o asimétrica y la selección adversa del prestatario aunada al riesgo del no pago. En el otro extremo, más heterodoxo, el colectivismo, el capital social y la formación de redes informales y sociedades de crédito suelen reducir los costes de transacción ligados al problema de la financiación. Este tipo de organización facilita el desenvolvimiento del cooperativismo en la economía. En México, después de la Revolución y la conformación de un régimen político autoritario y vertical, el cooperativismo se constituyó en uno de los referentes de la organización campesina para conseguir crédito de la banca pública y

  15. Diet of blue marlin Makaira mazara off the coast of Cabo San Lucas, Baja California Sur, Mexico

    OpenAIRE

    Abitia Cárdenas, Leonardo Andrés; Galván Magaña, Felipe; Gutiérrez Sánchez, Francisco Javier; Rodríguez Romero, Jesús; Aguilar Palomino, Bernabé; Moehl Hitz, Almiae

    1999-01-01

    Analysis of the stomach contents of 204 blue marlin (Makaira mazara) caught by the sport-fishing fleet of Cabo San Lucas in the southern Gulf of California is presented. The specimens sampled were caught during the summer and fall of 1987, 1988, and 1989 when the sea is warm (28-30°C). Blue marlin were found to feed on 35 prey species, 3 of which represented 90% of the total stomach contents by frequency of occurrence. The main prey were epipelagic organisms from the oceanic zone and demersal...

  16. Regional Planning in California: Objectives, Obstacles, and Alternatives

    Science.gov (United States)

    Deegan, William L.; Alford, Janis C.

    1976-01-01

    At the direction of the California State Legislature, the authors explored regional planning in other states as well as in California in an effort to determine the advantages and disadvantages of voluntary versus mandated interinstitutional cooperation. In this revised report the current state of regional planning and various alternatives for…

  17. Crecimiento y mortalidad de la concha nácar Pteria sterna en bancos silvestres de Baja California Sur, México

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    Humberto Wright-López

    2009-09-01

    Full Text Available La concha nácar Pteria sterna sustenta los perlicultivos en México, y es la base de producción de perlas en el continente Americano. Está bajo protección especial desde 1994, y solo puede capturarse semilla natural para cultivo e investigación. Determinamos su crecimiento y mortalidad en bancos silvestres, registrando la altura de ostras de Santa Rosalía, Mulegé y Bahía de Loreto (1997-99. La longitud máxima estimada fue 130.35 mm (124.22-136.48 mm, P>0.95. Las frecuencias de longitudes se ordenaron en un "año virtual" (Guanco 1991. Los parámetros de crecimiento de von Bertalanffy estimados con el programa ELEFAN I fueron: L∞= 156.02 mm, k=0.48año-1, t0=-0.216 años, C= 0.43 y WP = 0.73; el índice de desempeño de crecimiento fue Φ’ = 4.068. La mortalidad total fue de Z = 3.34 año -1por longitud convertida a curva de captura. La regresión del peso total y la altura tuvo la expresión W = 0.000756 * L(i2.7075 (r²=0.90, n=233. Mostramos la diferencia entre los parámetros de crecimiento en condiciones de repoblamiento experimental y aquellos de individuos silvestres de P. sterna. El valor de mortalidad total es comparable a aquellos de Pinctada fucata en el mar Rojo o P. radiata en el mar Mediterráneo.Growht and mortality of the mollusk Pteria sterna in wild banks of Southern Baja California, Mexico. The Gulf of California nacre shell Pteria sterna is an important marine resource in Mexico, and the main species for "half" and round pearl production in the American continent. Wild spat can only be extracted legally for research or culture activities. This study calculates growth and mortality parameters for wild stocks in the eastern coast of Southern Baja California. Height’s data (353 dorso-ventral measurements were taken from 1997 to 1999 at Santa Rosalía, Mulegé and Loreto Bay coast. The maximum length was estimated at 130.35 mm (124.22-136.48 mm, p>0.95. The length frequency data were set in a "virtual year

  18. Constraints on the rheology of the lower crust in a strike-slip plate boundary: evidence from the San Quintín xenoliths, Baja California, Mexico

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    T. van der Werf

    2017-12-01

    Full Text Available The rheology of lower crust and its transient behavior in active strike-slip plate boundaries remain poorly understood. To address this issue, we analyzed a suite of granulite and lherzolite xenoliths from the upper Pleistocene–Holocene San Quintín volcanic field of northern Baja California, Mexico. The San Quintín volcanic field is located 20 km east of the Baja California shear zone, which accommodates the relative movement between the Pacific plate and Baja California microplate. The development of a strong foliation in both the mafic granulites and lherzolites, suggests that a lithospheric-scale shear zone exists beneath the San Quintín volcanic field. Combining microstructural observations, geothermometry, and phase equilibria modeling, we estimated that crystal-plastic deformation took place at temperatures of 750–890 °C and pressures of 400–560 MPa, corresponding to 15–22 km depth. A hot crustal geotherm of 40 ° C km−1 is required to explain the estimated deformation conditions. Infrared spectroscopy shows that plagioclase in the mafic granulites is relatively dry. Microstructures are interpreted to show that deformation in both the uppermost lower crust and upper mantle was accommodated by a combination of dislocation creep and grain-size-sensitive creep. Recrystallized grain size paleopiezometry yields low differential stresses of 12–33 and 17 MPa for plagioclase and olivine, respectively. The lower range of stresses (12–17 MPa in the mafic granulite and lherzolite xenoliths is interpreted to be associated with transient deformation under decreasing stress conditions, following an event of stress increase. Using flow laws for dry plagioclase, we estimated a low viscosity of 1.1–1.3×1020 Pa ⋅ s for the high temperature conditions (890 °C in the lower crust. Significantly lower viscosities in the range of 1016–1019 Pa ⋅ s, were estimated using flow laws for wet plagioclase. The

  19. Synthesis of gravity, magnetic and thermal studies at the Las Tres Virgenes geothermal zone, Baja California Sur, Mexico. Sintesis de los estudios de gravimetria, magnetometria y termometria en la zona geotermica de Las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Estrada, Gerardo (Departamento de Exploracion, Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)); Gonzalez Lopez, Macario (Residencia General de Cerro Prieto, Mexicali (Mexico))

    1998-01-15

    Las Tres Virgenes geothermal zone is located in the NE-SW central sector of a sigmoidal basin that regionally has a NW-SE trend. In the local deepest zone there is a NE-SE granodioritic basement horst acting as hydrologic barrier, that makes the fluids flow up. After moving in a direction parallel to the local horst, waters continue its regional SE-NW movement controlled by regional tectonics. The flanks of the granodioritic basement horst, and local N-S faulting act as fluid paths in the hydrothermal zone, but regional NW-SE regional faults determine the general flow direction. Both regional and local tectonics show magnetic evidences of the emplacement of magmatic bodies of intermediate to basic composition. Those along NW-SE trends are more noticeable but we consider they are not the present day heat source. Intermediate magmatism along NE-SW local trend seems to be less extensive but it is younger, so, we consider it constitutes the heat source of the hydrothermal system. Thermal data suggest that the heat source is located below the volcanic chain toward the S or SW of the wells, phenomena related with the general displacement of magmatism from NE to SW along the volcanic chain. However, recent intensive faulting permits a higher permeability in the northern sector in which there are slightly smaller temperatures but at shallower depths and with higher flow rates.

  20. An economical non-destructive method for estimating eelgrass, Zostera marina (Potamogetonaceae leaf growth rates: formal development and use in northwestern Baja California

    Directory of Open Access Journals (Sweden)

    Elena Solana-Arellano

    2008-09-01

    Full Text Available Seagrass beds provide much of the primary production in estuaries; host many fishes and fish larvae, and abate erosion. The present study presents original analytical methods for estimating mean leaf-growth rates of eelgrass (Zostera marina. The method was calibrated by using data collected in a Z. marina meadow at Punta Banda estuary in Baja California, Mexico. The analytical assessments were based on measurements of leaf length and standard regression procedures. We present a detailed explanation of the formal procedures involved in the derivation of these analytical methods. The measured daily leaf-growth rate was 10.9 mm d-1 leaf-1. The corresponding value projected by our method was 10.2 mm d-1 leaf-1. The associated standard errors were of 0.53 and 0.56 mm d-1 leaf-1 respectively. The method was validated by projecting leaf-growth rates from an independent data set, which gave consistent results. The use of the method to obtain the mean leaf growth rate of a transplanted plot is also illustrated. Comparison of our leaf-growth data with previously reported assessments show the significant forcing of sea-surface temperature on eelgrass leaf dynamics. The formal constructs provided here are of general scope and can be applied to equivalent eelgrass data sets in a straightforward manner. Rev. Biol. Trop. 56 (3: 1003-1013. Epub 2008 September 30.Las praderas de pastos marinos abaten la erosión y aportan gran parte de la productividad primaria de los esteros y son refugio de muchos peces y sus larvas. El presente trabajo introduce métodos analíticos para estimar las tasas medias de crecimiento foliar de Zostera marina L. y sus varianzas. La calibración del método se llevó a cabo utilizando datos de una pradera de esta fanerógama en el Estero de Punta Banda Baja California, México. Las referidas estimaciones analíticas, se basan en medias de longitud foliar y en procedimientos estandarizados de regresión. Dichas determinaciones son por

  1. Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ingle, J.C. Jr.

    1982-01-01

    Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence occurring in 8 samples; in situ littoral and neritic species of benthic foraminifera occur in 5 samples with planktic species present in 2 samples. Distributional patterns of ostracodes and foraminifera together with previously analyzed lithofacies (Lyons and van de Kamp, 1980) indicate that the Cerro Prieto section represents an intertonguing complex of alluvial, deltaic, estuarine, and shallow marine environments deposited along the front of the Colorado River delta as it prograded across the Salton Trough during Pliocene and Pleistocene time. Foraminiferal evidence indicates that a sand and shale unit commonly present at depths between 700 and 1100 m represents a significant mid-Pleistocene marine incursion in the Cerro Prieto area. Tentative correlation of the Cerro Prieto section with the well dated Palm Springs Formation of the Imperial Valley, California area suggests that the Pliocene/Pleistocene boundary occurs at a depth of approximately 2000 m in the area of well M-93. Reworked specimens of Cretaceous foraminifera and fragments of the Cretaceous pelecypod Inoceramus were found in five samples further substantiating the Colorado Plateau provenance of a significant portion of the Colorado River deltaic sediments in the Cerro Prieto area.

  2. Educación para la prevención del VIH-SIDA para inmigrantes indígenas en Baja California

    Directory of Open Access Journals (Sweden)

    Elizabeth Maier

    2007-01-01

    Full Text Available El objetivo del presente artículo es anclar el análisis de una experiencia de investigación-acción en educación, para la prevención del VIH-SIDA en comunidades indígenas inmigrantes en Baja California, a un marco teórico y fenomenológico que organice las dimensiones múltiples de la problemática, y permita mayor comprensión del significado de la pandemia para estas comunidades, el sentido de la participación de las actoras principales del proyecto, sus resultados, las implicaciones de la articulación de la perspectiva de género y una orientación cultural para su éxito. Se utiliza la categoría vulnerabilidad, para ejemplificar las condiciones de vida tan frágiles de las comunidades indígenas de origen y recepción, los significados subalternos de la identidad tradicional de las indígenas y los riesgos propios de la migración. El artículo interpreta el ejercicio de promoción de la salud comunitaria a partir del sentido cultural de género de las comunidades de origen, los significados históricos y subjetivos de la emigración indígena creciente y los ensayos consiguientes de reorganización social, cultural y genérica, causados por la dislocación migratoria. A partir de este complejo rompecabezas teórico, histórico, fenomenológico y relacional, en los últimos apartados se examina la mecánica del proyecto, sus contenidos y el cúmulo de resultados que la experiencia arrojó a la comunidad y a las promotoras.

  3. Resource use of an aquacultured shellfish in the reverse estuary Bahía San Quintín, Baja California, México

    Science.gov (United States)

    Wilkinson, G. M.; Emery, K.; Camacho-Ibar, V.; Pace, M.; McGlathery, K.; Sandoval Gil, J.; Hernandez-Lopez, J.

    2016-02-01

    Shellfish aquaculture is prominent in many coastal and estuarine environments. Filter feeding by cultured shellfish connects the benthic and pelagic environments in coastal ecosystems. Bahía San Quintín is a reverse estuary in Baja California, Mexico, where Pacific oysters (Crassostrea gigas) are cultivated. While oysters likely feed heavily on phytoplankton especially during upwelling periods, we hypothesized that other forms of organic matter available in high quantities such as seagrass (Zostera marina) and macroalgae (Ulva spp.) must also be used by the oysters, especially in the most inshore portions of the bay. We measured the carbon and hydrogen stable isotope composition of oysters and their potential food resources at upper, mid, and lower bay sites during upwelling and non-upwelling seasons and applied a Bayesian mixing model to evaluate resource use. Hydrogen isotopes provided a large separation between potential food resources. Although we did not find any strong seasonal effects due to upwelling, there was a strong spatial gradient in resource use. Phytoplankton were most important at the lower (oceanic) site (median resource use for two sampling times, 68 and 79 %) and decreased up the estuary as macroalgae became more important (43 and 56 % at the upper site). At all sites for both sampling times, seagrass was an unimportant resource for oysters. The contrast between high phytoplankton use at the lower site and increased macroalgal use at the upper site is likely due to available resource biomass. Our results illustrate the adaptability of oysters to varying resource availability and the possibility of a higher system carrying capacity than that based on phytoplankton alone given multiple potential food sources.

  4. Incidence of organochlorine pesticides and the health condition of nestling ospreys (Pandion haliaetus) at Laguna San Ignacio, a pristine area of Baja California Sur, Mexico.

    Science.gov (United States)

    Rivera-Rodríguez, Laura B; Rodríguez-Estrella, Ricardo

    2011-01-01

    We identified and quantified organochlorine (OC) pesticide residues in the plasma of 28 osprey (Pandion haliaetus) nestlings from a dense population in Laguna San Ignacio, a pristine area of Baja California Sur, Mexico, during the 2001 breeding season. Sixteen OC pesticides were identified and quantified. α-, β-, δ- and γ-hexachlorocyclohexane, heptaclor, heptachlor epoxide, endosulfan I and II, endosulfan-sulfate, p,p'-DDE, p,p'-DDD, aldrin, dieldrin, endrin, endrin aldehyde, and endrin ketone were the OCs found in the plasma of nestlings, ranging from 0.002 to 6.856 pg/μl (parts per billion). No differences were found in the concentration of pesticides between genders (P > 0.05). In our work, the concentrations detected in the plasma were lower than those reported to be a threat for the species and that affect the survival and reproduction of birds. The presence of OC pesticides in the remote Laguna San Ignacio osprey population is an indication of the ubiquitous nature of these contaminants. OCs are apparently able to travel long distances from their source to the study area. A significant relationship between hemoglobin and mean corpuscular hemoglobin concentrations and OC concentrations were found suggesting that a potential effect on the health of chicks may exist in this osprey population caused by the OC, e.g. anemia. The total proteins were positively correlated with α-BHC, endosulfan I, and p,p'-DDD. It has been suggested that OC also affects competitive interactions and population status over the long term in vertebrate species, and our results could be used as reference information for comparison with other more exposed osprey populations.

  5. Tracing toxic elements sources using lead isotopes: An example from the San Antonio–El Triunfo mining district, Baja California Sur, México

    International Nuclear Information System (INIS)

    Gutiérrez-Caminero, Leopoldo; Weber, Bodo; Wurl, Jobst; Carrera-Muñoz, Mariela

    2015-01-01

    Highlights: • Provenance of toxic elements is investigated in a basin close to the mining district. • Stable lead isotope analyses assist to distinguish between sources of toxic elements. • Two major sources are identified: mine tailings and fault bounded mineralization. • There is evidence in the detritus of a different natural lead component. • An additional anthropogenic lead input is detectable from the soluble phases. - Abstract: Pollution of sediments and water bodies with toxic elements around the San Antonio–El Triunfo mining district, Baja California Sur, México is probably sourced from the tailings of abandoned mines that are hosted in mineralized Cretaceous granitoids. However, there is evidence to suggest local hot springs related to recent faults may be an additional source for contamination in the area. In this study, lead isotope signatures are applied to draw conclusions with regard to potential sources of toxic elements. Lead isotope ratios were analyzed from sulfides and scoria from the abandoned mines, fluvial sediments, and igneous rocks with secondary disseminated mineralization. To differentiate between superposed secondary and residual primary lead, leaching experiments were performed, and both leachate and residues were analyzed separately. Most of the residues from sediment samples have lead isotope ratios similar to those from the sulfides and scoria of the mining district, indicating that most of the lead in the detritus is related to the mineralized plutons. However, there is evidence of an additional detrital component. Lead isotope ratios from the leachates indicate a different source for the superimposed lead that is best explained by the contamination with the average Mexican industrial lead. Secondary disseminated mineralization that is related to younger, deep structures (hot springs) has different lead isotope ratios compared to massive vein sulfides and accounts for a significant amount in areas with high

  6. Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Meacham, Meredith C; Roesch, Scott C; Strathdee, Steffanie A; Lindsay, Suzanne; Gonzalez-Zuniga, Patricia; Gaines, Tommi L

    2018-01-01

    Patterns of polydrug use among people who inject drugs (PWID) may be differentially associated with overdose and unique human immunodeficiency virus (HIV) risk factors. Subgroups of PWID in Tijuana, Mexico, were identified based on substances used, route of administration, frequency of use and co-injection indicators. Participants were PWID residing in Tijuana age ≥18 years sampled from 2011 to 2012 who reported injecting an illicit substance in the past month (n = 735). Latent class analysis identified discrete classes of polydrug use characterised by 11 indicators of past 6 months substance use. Multinomial logistic regression examined class membership association with HIV risk behaviours, overdose and other covariates using an automated three-step procedure in mplus to account for classification error. Participants were classified into five subgroups. Two polydrug and polyroute classes were defined by use of multiple substances through several routes of administration and were primarily distinguished from each other by cocaine use (class 1: 5%) or no cocaine use (class 2: 29%). The other classes consisted primarily of injectors: cocaine, methamphetamine and heroin injection (class 3: 4%); methamphetamine and heroin injection (class 4: 10%); and heroin injection (class 5: 52%). Compared with the heroin-only injection class, memberships in the two polydrug and polyroute use classes were independently associated with both HIV injection and sexual risk behaviours. Substance use patterns among PWID in Tijuana are highly heterogeneous, and polydrug and polyroute users are a high-risk subgroup who may require more tailored prevention and treatment interventions. [Meacham MC, Roesch SC, Strathdee SA, Lindsay S, Gonzalez-Zuniga P, Gaines TL. Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico. Drug Alcohol Rev 2018;37:128-136].

  7. Current depression among women in California according to residence in the California-Mexico border region.

    Science.gov (United States)

    Ryan-Ibarra, Suzanne; Epstein, Joan Faith; Induni, Marta; Wright, Michael A

    2012-05-01

    To estimate the prevalence of current depression; examine the relationship between current depression and immigration, health status, health care access, and health behaviors; and assess differences by California-Mexico border region (Imperial and San Diego Counties) among women in California. Using a cross-sectional, representative sample of adult women from the California Women's Health Survey (n = 13 454), a statewide telephone survey, prevalence of current depression and predictors of depression were examined in California and according to border region residence. Depression was assessed with the eight-item Patient Health Questionnaire. The prevalence of current depression for women in California was 12.0%. It was similar in the border (13.0%) and the nonborder (11.9%) regions. Odds of current depression in women were lower among recent immigrants (depression and health status, health care access, and binge drinking were larger in the border region than outside the border region. Similar prevalences of current depression were observed among those who live in the border region of California and in those who do not, but the relationship between depression and health status, health care access, and binge drinking varied by border region residence. Ideally, future surveillance of depression and its predictors along the Mexico-California border will be conducted binationally to inform interventions and tracking such as the Healthy Border Program's objectives.

  8. Derechos colectivos y consulta previa: territorio cucapá y recursos pesqueros en Baja California, México

    Directory of Open Access Journals (Sweden)

    Alejandra Navarro Smith

    2014-07-01

    Full Text Available Las demandas de reconocimiento de derechos territoriales y de uso de los recursos naturales que los pescadores cucapás le hacen al Estado mexicano, desde 1993, después de la creación de la Reserva del Alto Golfo de California y Delta del Río Colorado (en adelante, la Reserva, son unas más en el panorama de los problemas socioambientales y de despojo territorial, que afectan a los pueblos originarios en México. La característica particular en este caso es que el Estado mismo es quien construye los marcos legales en materia de protección a las especies —sin consultar debidamente a dichos pueblos—, volviendo ilegal la presencia cucapá en esa zona y vulnerando sus derechos como población indígena del delta. En consecuencia, las autoridades medioambientales y de pesca mexicanas han constituido la zona del delta del río Colorado como un territorio en disputa, al implementar esquemas de protección ambiental y de pesca, sustentados en modelos disciplinarios, que únicamente se alimentan de información biológica y pesquera. El conflicto se genera cuando se deja al elemento humano fuera de los análisis, como si las comunidades asentadas en los territorios protegidos y usuarias de los recursos no formaran parte de los ecosistemas. Al crear el núcleo de la Reserva en el mismo lugar donde se encontraban los campamentos de pesca del pueblo cucapá se volvió ilegal el aprovechamiento de los recursos pesqueros en la zona. En este contexto se han criminalizado las acciones de resistencia con las que los cucapás responden ante la regulación medioambiental del delta del río Colorado. Al ver imposibilitada la continuidad de su práctica pesquera, los habitantes se organizan para defender su acceso al territorio y, en un sentido más amplio, sus formas de vida y de trabajo. Este caso, en particular, visibiliza maneras contemporáneas por las que el Estado despoja el territorio y desaparece prácticas culturales propias de los pueblos

  9. Interaction of Extreme Halophilic Archaea With the Evaporites of the Solar Salterns Guerrero Negro Baja California, Mexico

    Science.gov (United States)

    Tamez, P.; Lopez-Cortés, A.

    2008-12-01

    morphology. Other strain match, with 99% of similarity, with three sequences Haloarcula: Haloarcula japonica (EF645686), Haloarcula hispanica (DQ089681) and Haloarcula marismortui (X61689), differences among them were only 3 base pairs. We suggest that strain, C205030908, could correspond to Haloarcula californiae previously reported by Javor et al, (1982), from which there is not sequence known. Nested-PCR-DGGE analysis showed a pattern of 11 bands, meaning the archaeal community is more complex than we could detect by culture approach.

  10. Arsenic Concentration in the Surface Water of a Former Mining Area: The La Junta Creek, Baja California Sur, Mexico

    Science.gov (United States)

    Imaz Lamadrid, Miguel; Acosta Vargas, Baudilio

    2018-01-01

    The mining activity in the San Antonio-El Triunfo district, located in a mountainous region at 60 km southeast of La Paz, occured for more than 250 years and left behind severe contamination of soils and riverbed sediments which led to elevated concentrations of arsenic and other trace elements in the surface- and groundwater of the region. Although the main mining activity ended around 1911, contamination is still beeing distributed, especially from left behind tailings and mine waste piles. The contamination levels in the groundwater have been reported in several studies, but there is little information available on the surface water quality, and especially the temporal variation. In this study, we analyzed the surface water of the La Junta creek, in the southern part of the San Antonio-El Triunfo mining district. The working hypothesis was that by means of a spatial analysis of surface water and shallow groundwater, in combination with the temporal observation of the concentrations in runoff water, the effects of different sources of arsenic (natural geogene anomalies, due to historic mining activity, and hydrothermal related impact) in the La Junta creek can be recognized. This present study revealed that historic mining activity caused a mojor impact of arsenic but less contamination was observed than in the northern part of the district and elevated arsenic concentrations in stream water generally occurred during times of low streamflow. PMID:29498700

  11. Manejo de un sitio de anidación para la conservación de Sternula antillarum (Charadriiformes: Laridae en Baja California Sur, México Nesting site management for Sternula antillarum (Charadriiformes: Laridae conservation in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Edgar Amador

    2008-06-01

    Full Text Available El gallito marino menor (Sternula antillarum es una especie sujeta a protección especial, que anida en colonias pequeñas en hábitats costeros. Las mareas altas son un problema para la anidación de S. antillarum en Baja California Sur, pues causan la inundación de algunas colonias. Para reducir el impacto potencial del flujo de marea alta sobre los nidos, se elevó 20 cm el nivel del suelo por medio de una plataforma elevada construida con llantas de desecho rellenas y cubiertas de arena. La ocupación de este sitio por S. antillarum se monitoreó durante las temporadas reproductivas de 1990, y de 2002 a 2005. Las mareas altas no afectaron los nidos establecidos sobre la plataforma y la densidad de nidos sobre ella fue mayor que la que hubo en el terreno natural de la planicie costera adyacente. Este método de manejo del hábitat de anidación de S. antillarum es una buena alternativa en los sitios con riesgo por flujo de marea.The Least Tern (Sternula antillarum is a threatened seabird species that breeds in small colonies on coastal habitats. High tides constitute a problem for their reproduction in Baja California Sur, since they cause flooding of some colonies. To reduce the potential impact of high tides on the nests, the level of the ground was elevated by 20 cm, through an elevated platform that was built by using discarded tires filled and covered with sand. The occupation of this site by Least Terns was monitored during the breeding seasons of 1990 and from 2002 to 2005. High tides did not affect the nests established on the platform and density of nests on this platform was higher than on the natural adjacent mudflat area. This nesting habitat management method for the Least Tern is an appropriate alternative for those sites affected by high tides.

  12. Water flowing north of the border: export agriculture and water politics in a rural community in Baja California.

    Science.gov (United States)

    Zlolniski, Christian

    2011-01-01

    Favored by neoliberal agrarian policies, the production of fresh crops for international markets has become a common strategy for economic development in Mexico and other Latin American countries. But as some scholars have argued, the global fresh produce industry in developing countries in which fresh crops are produced for consumer markets in affluent nations implies “virtual water flows,” the transfer of high volumes of water embedded in these crops across international borders. This article examines the local effects of the production of fresh produce in the San Quintín Valley in northwestern Mexico for markets in the United States. Although export agriculture has fostered economic growth and employment opportunities for indigenous farm laborers, it has also led to the overexploitation of underground finite water resources, and an alarming decline of the quantity and quality of water available for residents’ domestic use. I discuss how neoliberal water policies have further contributed to water inequalities along class and ethnic lines, the hardships settlers endure to secure access to water for their basic needs, and the political protests and social tensions water scarcity has triggered in the region. Although the production of fresh crops for international markets is promoted by organizations such as the World Bank and Inter-American Development Bank as a model for economic development, I argue that it often produces water insecurity for the poorest, threatening the UN goal of ensuring access to clean water as a universal human right.

  13. Fault Length Vs Fault Displacement Evaluation In The Case Of Cerro Prieto Pull-Apart Basin (Baja California, Mexico) Subsidence

    Science.gov (United States)

    Glowacka, E.; Sarychikhina, O.; Nava Pichardo, F. A.; Farfan, F.; Garcia Arthur, M. A.; Orozco, L.; Brassea, J.

    2013-05-01

    The Cerro Prieto pull-apart basin is located in the southern part of San Andreas Fault system, and is characterized by high seismicity, recent volcanism, tectonic deformation and hydrothermal activity (Lomnitz et al, 1970; Elders et al., 1984; Suárez-Vidal et al., 2008). Since the Cerro Prieto geothermal field production started, in 1973, significant subsidence increase was observed (Glowacka and Nava, 1996, Glowacka et al., 1999), and a relation between fluid extraction rate and subsidence rate has been suggested (op. cit.). Analysis of existing deformation data (Glowacka et al., 1999, 2005, Sarychikhina 2011) points to the fact that, although the extraction changes influence the subsidence rate, the tectonic faults control the spatial extent of the observed subsidence. Tectonic faults act as water barriers in the direction perpendicular to the fault, and/or separate regions with different compaction, and as effect the significant part of the subsidence is released as vertical displacement on the ground surface along fault rupture. These faults ruptures cause damages to roads and irrigation canals and water leakage. Since 1996, a network of geotechnical instruments has operated in the Mexicali Valley, for continuous recording of deformation phenomena. To date, the network (REDECVAM: Mexicali Valley Crustal Strain Measurement Array) includes two crackmeters and eight tiltmeters installed on, or very close to, the main faults; all instruments have sampling intervals in the 1 to 20 minutes range. Additionally, there are benchmarks for measuring vertical fault displacements for which readings are recorded every 3 months. Since the crackmeter measures vertical displacement on the fault at one place only, the question appears: can we use the crackmeter data to evaluate how long is the lenth of the fractured fault, and how quickly it grows, so we can know where we can expect fractures in the canals or roads? We used the Wells and Coppersmith (1994) relations between

  14. La inmigración de jubilados estadounidenses en México y sus prácticas transnacionales: Estudio de caso en Mazatlán, Sinaloa y Cabo San Lucas, Baja California Sur

    OpenAIRE

    Lizárraga Morales, Omár

    2008-01-01

    En este artículo se analiza la migración de jubilados estadounidenses hacia México, particularmente en dos localidades en el noroeste del país: Mazatlán, Sinaloa y Cabo San Lucas en Baja California Sur. Este es un flujo migratorio que se dirige en dirección contraria a la que tradicionalmente se estudia en la migración internacional, y tiene un rápido crecimiento en algunos destinos mexicanos, pues está compuesto por los integrantes de la generación del baby boom. Se describen las estructuras...

  15. La micro y pequeña empresa como generadora de empleo en Baja California durante la crisis de 2008-2009

    Directory of Open Access Journals (Sweden)

    Alejandro Mungaray Lagarda

    2016-01-01

    Full Text Available El objetivo del trabajo ha sido evaluar la importancia de la conformación del tejido empresarial en la evolución de la actividad económica y la generación de empleo en Baja California en el entorno de la crisis global de 2008-2009, con énfasis en el comportamiento de la micro y pequeña empresa. Lo anterior se consigue a través de la metodología de un análisis de correspondencias de carácter exploratorio y otro econométrico con fines confirmatorios en los cuales se utilizaron variables de los estratos empresariales y los sectores económicos una vez revisados los indicadores poblacionales, migratorios y de la estructura productiva. Como resultados se encontró una relación directa y significativa de las microempresas con el volumen de negocios y el empleo durante la crisis, sin embargo, en el periodo post-crisis (2010-2014 la aportación de la pequeña empresa resultó muy superior. Por su parte, las grandes empresas, mostraron menor sensibilidad general y una reducción de su capacidad para generar empleo aún durante el periodo post-crisis. En cualquier caso, debemos señalar que la limitante es que los resultados deben ser tomados con cautela debido a la alta segregación por estrato. Se concluye que no es posible rechazar la hipótesis de que la micro, pero sobre todo la pequeña empresa jugó un papel estratégico en la generación de empleo y dinamismo económico durante el periodo de crisis, contribuyendo incluso a aminorar su impacto, por lo que se debe fortalecer una política industrial que favorezca el aprendizaje y la innovación de este sector empresarial.

  16. Economic, environmental and social impacts of geothermal development, and energy savings and efficient use of power in Baja California, Mexico; Impactos economicos, ambientales y sociales del desarrollo geotermico y del ahorro y uso eficiente de la electricidad en Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Campbell R, Hector E.; Montero A, Gisela [Universidad Autonoma de Baja California, Instituto de Ingenieria, Mexicali, Baja California (Mexico)]. E-mail: hecr@iing.mxl.uabc.mx; Lambert A., Alejandro A. [Universidad Autonoma de Baja California, Facultad de Ingenieria, Mexicali, Baja California (Mexico)

    2011-01-15

    This essay of electrical planning for Baja California, Mexico, includes diagnosis of power production and consumption from 1994-2005, prospective to 2025 if historical trends are maintained, discussion of a systemic plan and its impact on the prospective through energy savings and energy efficient use, combined with an increase of the geothermal energy share. Diagnosis indicates that geothermal capacity in 1998 accounted for 57% of total electric capacity in Baja California, and by 2004 73% of this total electric capacity was based on natural gas, increasing energy dependence on fossil fuels. During this period, electric generation changed from a ratio of 2 to 1 (geothermal steam to fuel oil) to 1 to 1 (geothermal steam to natural gas). The unit cost of natural gas energy with an efficiency of 50% is 24 times the cost of the same unit of geothermal steam with 16% efficiency. Power generation, with fuel oil or simple cycle turbines firing natural gas, costs twice that of combined cycle turbines, while the costs are three times less with geothermal steam. In 2005, as a consequence of a minor contribution of geothermal energy to the power-generation total, production costs increased, reaching $122.80 USD/MWh. The replacement of fuel oil, as power fuel, decreased the SO{sub x} emissions from 4.16 kg/MWh to 0.19 kg/MWh. The combined-cycle fired by natural gas diminished the relative emissions of NO{sub x} and CO{sub 2} by 30%, but the 2.6 million tons of CO{sub x} given off each year did no vary significantly. Using geothermal energy avoids burning 20 million barrels of oil equivalent annually. The Prospective 2005-2025 indicates Baja California requires the installation of an additional 4500 MW to reach 7200 MW. The energy portfolio will become more dependent on natural gas increasing its share from 60% to 86%. Geothermal energy will decrease its share in installed capacity to 10%, eliminating the damping effect on the cost of production. SO{sub x} emissions will

  17. California Migrant Student Movement Study--Region 3 Analysis.

    Science.gov (United States)

    Davis, Benjamin G.

    The five counties of Madera, Merced, Contra Costa, San Joaquin and Stanislaus constitute Region 3 of the California Migrant Education Program. A study to evaluate movement patterns of migrant students from, to and within the state was conducted using data from the Migrant Student Record Transfer System. It indicates that in 1977 Region 3 ranked…

  18. Evaluación del impacto socioeconómico de la Reserva de la Biosfera Alto Golfo de California y Delta del Río Colorado en la actividad pesquera ribereña de San Felipe, Baja California, México

    OpenAIRE

    Carlos Israel Vázquez León; José Luis Fermán Almada

    2010-01-01

    Desde 1993 las comunidades de Puerto Peñasco y Golfo de Santa Clara, Sonora, y San Felipe, Baja California, en México, están vinculadas por la Reserva de la Biosfera Alto Golfo de California y Delta del Río Colorado; creada para proteger varias especies endémicas, entre ellas al mamífero conocido como vaquita marina (Phocoenasinus) y la totoaba (Totoaba macdonaldii).Aquí se analiza el efecto socioeconómico que en la pesca de San Felipe tuvo en 1994 y 2002 la creación de la reserva; concebida ...

  19. Prevalence and Correlates of Heroin–Methamphetamine Co-Injection Among Persons Who Inject Drugs in San Diego, California, and Tijuana, Baja California, Mexico

    Science.gov (United States)

    Meacham, Meredith C.; Strathdee, Steffanie A.; Rangel, Gudelia; Armenta, Richard F.; Gaines, Tommi L.; Garfein, Richard S.

    2016-01-01

    Objective: Although persons who inject drugs (PWID) in the western United States–Mexico border region are known to inject both heroin and methamphetamine, little is known about the prevalence and risks associated with co-injection of this depressant–stimulant combination (also known as “goofball” and “Mexican speedball”). Method: Baseline data from parallel cohort studies of PWID conducted concurrently in San Diego, CA, and Tijuana, Mexico, were used to estimate the prevalence and identify correlates of heroin–methamphetamine co-injection. PWID older than 18 years of age who reported injecting illicit drugs in the past month (N = 1,311; 32.7% female) were recruited in San Diego (n = 576) and Tijuana (n = 735) and completed interviewer-administered questionnaires. Bivariate and multivariable logistic regression analyses were used to identify correlates of heroin–methamphetamine co-injection. Results: The prevalence of co-injection in the past 6 months was 39.9% overall and was higher in Tijuana (55.8%) than in San Diego (19.8%). In multivariable analyses adjusting for study cohort, distributive syringe sharing, purchasing syringes prefilled with drugs, finding it hard to get new syringes, reporting great or urgent need for treatment, and younger age were independently associated with co-injection. Past-6-month overdose was significantly associated with higher odds of co-injection in San Diego than in Tijuana. Conclusions: These findings indicate that heroin–methamphetamine co-injection is more common in Tijuana than in San Diego, yet this practice was only associated with overdose in San Diego. Heroin–methamphetamine co-injection was also independently associated with HIV-associated injection risk behaviors. Overdose-prevention interventions should address co-injection of depressants and stimulants. PMID:27588536

  20. Prevalence and Correlates of Heroin-Methamphetamine Co-Injection Among Persons Who Inject Drugs in San Diego, California, and Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Meacham, Meredith C; Strathdee, Steffanie A; Rangel, Gudelia; Armenta, Richard F; Gaines, Tommi L; Garfein, Richard S

    2016-09-01

    Although persons who inject drugs (PWID) in the western United States-Mexico border region are known to inject both heroin and methamphetamine, little is known about the prevalence and risks associated with co-injection of this depressant-stimulant combination (also known as "goofball" and "Mexican speedball"). Baseline data from parallel cohort studies of PWID conducted concurrently in San Diego, CA, and Tijuana, Mexico, were used to estimate the prevalence and identify correlates of heroin-methamphetamine co-injection. PWID older than 18 years of age who reported injecting illicit drugs in the past month (N = 1,311; 32.7% female) were recruited in San Diego (n = 576) and Tijuana (n = 735) and completed interviewer-administered questionnaires. Bivariate and multivariable logistic regression analyses were used to identify correlates of heroin-meth-amphetamine co-injection. The prevalence of co-injection in the past 6 months was 39.9% overall and was higher in Tijuana (55.8%) than in San Diego (19.8%). In multivariable analyses adjusting for study cohort, distributive syringe sharing, purchasing syringes prefilled with drugs, finding it hard to get new syringes, reporting great or urgent need for treatment, and younger age were independently associated with co-injection. Past-6-month overdose was significantly associated with higher odds of co-injection in San Diego than in Tijuana. These findings indicate that heroin-methamphetamine co-injection is more common in Tijuana than in San Diego, yet this practice was only associated with overdose in San Diego. Heroin-methamphetamine coinjection was also independently associated with HIV-associated injection risk behaviors. Overdose-prevention interventions should address co-injection of depressants and stimulants.

  1. Interactions between western gall rust and its Pinus hosts, P. jeffreyi and P. contorta, in Sierra De San Pedro Martir National Park, Northern Baja California, Mexico

    Science.gov (United States)

    Detlev R. Vogler; Brian W. Geils

    2008-01-01

    The Sierra de San Pedro Martir is a mountain range in north-central Baja that comprises the southern-most extension of the Californian coniferous flora, including Pinus jeffreyi, P. contorta, P. lambertiana, Abies concolor, and Calocedrus decurrens. These forests are similar...

  2. An annotated distributional checklist of exotic freshwater fishes from the Baja California Peninsula, Mexico Lista comentada sobre la distribución de peces dulceacuícolas exóticos de la península de Baja California, México

    Directory of Open Access Journals (Sweden)

    Gorgonio Ruiz-Campos

    2012-03-01

    Full Text Available We documented the distributional status of 27 exotic fish species in the inland waters of the Baja California Peninsula, Mexico, based on voucher specimens collected from 122 sites between 1977 and 2010, and on published records. The species reported here are representatives of genera from the Atlantic drainages of North America (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella, and Micropterus, Middle America (Poecilia, Gambusia, and Xiphophorus, Eurasia (Cyprinus and Carassius, and Africa (Tilapia and Oreochromis. The family containing the highest number of species is Centrarchidae (7 species followed by Ictaluridae and Poeciliidae (6 species each. Four species were determined to be invasive due to their wide distribution and fast dispersal through the Peninsula (Gambusia affinis, Poecilia reticulata, Lepomis cyanellus, and Tilapia sp. cf. zillii. We analyze the impacts of exotic species on the native populations of 3 species with problems of conservation: Cyprinodon macularius (endangered, Fundulus lima (endangered, and Gasterosteus aculeatus (vulnerable. Alien fishes have been introduced for a variety of reasons in Mexico: ornament, sport, aquaculture, biological control, and by accident. In some cases fish introductions were carried out for more than one reason.El estatus de la distribución de peces exóticos es documentado para 27 especies en las aguas continentales de la península de Baja California, México, basado en registros de ejemplares recolectados en 122 localidades durante el período de 1977 a 2010, así como registros referidos en la literatura. Las especies aquí reportadas son representativas de géneros que proceden de la vertiente Atlántica de Norteamérica (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella y Micropterus, Mesoamérica (Poecilia, Gambusia y Xiphophorus, Eurasia (Cyprinus y Carassius y África (Tilapia y Oreochromis. La familia con mayor n

  3. Santa Ana Winds of Southern California: Their Climatology and Variability Spanning 6.5 Decades from Regional Dynamical Modelling

    Science.gov (United States)

    Guzman-Morales, J.; Gershunov, A.

    2015-12-01

    Santa Ana Winds (SAWs) are an integral feature of the regional climate of Southern California/Northern Baja California region. In spite of their tremendous episodic impacts on the health, economy and mood of the region, climate-scale behavior of SAW is poorly understood. In the present work, we identify SAWs in mesoscale dynamical downscaling of a global reanalysis product and construct an hourly SAW catalogue spanning 65 years. We describe the long-term SAW climatology at relevant time-space resolutions, i.e, we developed local and regional SAW indices and analyse their variability on hourly, daily, annual, and multi-decadal timescales. Local and regional SAW indices are validated with available anemometer observations. Characteristic behaviors are revealed, e.g. the SAW intensity-duration relationship. At interdecadal time scales, we find that seasonal SAW activity is sensitive to prominent large-scale low-frequency modes of climate variability rooted in the tropical and north Pacific ocean-atmosphere system that are also known to affect the hydroclimate of this region. Lastly, we do not find any long-term trend in SAW frequency and intensity as previously reported. Instead, we identify a significant long-term trend in SAW behavior whereby contribution of extreme SAW events to total seasonal SAW activity has been increasing at the expense of moderate events. These findings motivate further investigation on SAW evolution in future climate and its impact on wildfires.

  4. Modeling of Trans-boundary Transport of Air Pollutants in the California-Mexico Border Region during Cal-Mex 2010

    Science.gov (United States)

    Bei, N.; Zavala, M. A.; Lei, W.; Li, G.; Molina, L. T.

    2010-12-01

    The US and Mexico share a common air basin along the ~200 km border between California and Baja California. The economical activities in this region are heavily influenced by the international trade and commerce between Mexico and the US that mainly occurs through the borders of the sister cities of San Diego-Tijuana and Calexico-Mexicali. The diversity and differences in the characteristics of emissions sources of air pollutants in the California-Mexico border region make this an important area for the study of the chemistry and trans-boundary transport of air pollutants. During May-June of 2010, the Cal-Mex 2010 field campaign included a series of measurements aimed at characterizing the emissions from major sources in the California-Mexico border region and assessing the possible impacts of these emissions on local and regional air quality. In this work we will present the results of the use of the Comprehensive Air quality model with extensions (CAMx) in a modeling domain that includes the sister cities of San Diego-Tijuana and Calexico-Mexicali for studying events of trans-boundary transport of air pollutants during Cal-Mex 2010. The measurements obtained during the Cal-Mex 2010 field campaign are used in the evaluation of the model performance and in the design of air quality improvement policies in the California-Mexico border region.

  5. Composición taxonómica y relaciones zoogeográficas de los peces demersales de la costa occidental de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Jesús Rodríguez-Romero

    2008-12-01

    Full Text Available Se presenta la composición sistemática de peces demersales de la costa occidental de Baja California Sur, límite de distribución norte de la ictiofauna del Pacífico Oriental Tropical. Se realizaron cuatro cruceros oceanográficos durante otoño de 2004 a marzo de 2006. Este listado incluye 220 especies, 132 géneros y 73 familias. El 26.3% corresponde a especies de amplia distribución desde la Provincia de San Diego a la Provincia Panámica y el 21.7% son especies restringidas a la región del Pacífico Oriental Tropical. Seis especies representan nuevos registros para la zona o ampliación de su ámbito de distribución. Las familias mejor representadas en número de especies fueron Paralichthyidae y Scorpaenidae, con 16 especies cada una. El género mejor representado fue Sebastes con 9 especies. Se presentan los nombres comunes, intervalo de tallas y el estatus de cada especie dentro de la comunidadTaxonomic composition and zoogeographic relations of demersal in the western coast of Baja California Sur, Mexico. The composition of demersal fish along the western coast of the State of Baja California Sur, México, including the limit of the northern distribution of the ichthyofauna of the eastern tropical Pacific, is presented. The survey was carried out on four oceanographic cruises between autumn 2004 and March 2006. Of 220 species in 132 genera and 73 families, 26.3% are species of wide distribution from San Diego County, USA to Panama and 21.7% are species restricted to the eastern tropical Pacific. Six species are new findings for the area or range expansions. The families with the most species are Paralichthyidae and Scorpaenidae, each with 16 species. The most frequent genus was Sebastes, with nine species. We present a table with common Spanish names, size range and status of each species inside the community. Rev. Biol. Trop. 56 (4: 1765-1783. Epub 2008 December 12.

  6. Regional variations in breast cancer among california teachers.

    Science.gov (United States)

    Reynolds, Peggy; Hurley, Susan; Goldberg, Debbie E; Anton-Culver, Hoda; Bernstein, Leslie; Deapen, Dennis; Horn-Ross, Pamela L; Peel, David; Pinder, Richard; Ross, Ronald K; West, Dee; Wright, William E; Ziogas, Argyrios

    2004-11-01

    Observed regional differences in breast cancer incidence could provide valuable clues to the etiology of this disease. The pattern of historically higher breast cancer rates among residents of California's San Francisco Bay and Southern Coastal areas is evident in the disease experience among members of the California Teachers Study. This large cohort study has followed female professional school employees for cancer incidence since 1995 and has collected extensive information on breast cancer risk factors. Between 1996 and 1999, invasive breast cancer was diagnosed in 1562 of the 115,611 cohort members who could be geocoded to a California address in 1995 and who had no previous breast cancer diagnosis. Adjusted hazard rate ratios (HRs) were estimated through multivariate Cox proportional hazards modeling. Rates were higher for cohort members in the San Francisco Bay area (HR = 1.22; 95% confidence interval = 1.06-1.40) and Southern Coastal area (1.16; 1.04-1.30) compared with those in the rest of California. The distributions of variables representing socioeconomic status, urbanization, and personal risk factors were consistent with higher risks for cohort members residing in the San Francisco Bay and Southern Coastal areas. Adjustment for these factors, however, did not explain regional differences in incidence, resulting in HRs that remained elevated for these 2 areas. Regional differences in breast cancer incidence in this large, well-defined cohort are not easily explained by known risk factors.

  7. Efecto genético del aislamiento geográfico de la liebre negra (Lepus insularis), endémica de Isla Espíritu Santo, Baja California Sur, México

    OpenAIRE

    Cervantes, Fernando A.; Castañeda, Mario

    2012-01-01

    Este estudio evaluó la magnitud de la divergencia genética entre Lepus insularis y L. californicus xanti de la Península de Baja California causada por el aislamiento geográfico de L. insularis efectuando un análisis de aloenzimas. Los resultados se compararon con un sistema biogeográfico similar que se presenta entre L. c. sheldoni de Isla Carmen y L. c. martirensis con distribución de la región norte de la Península. Se examinaron 26 loci con muestras de tejido de corazón y riñón mediante l...

  8. Reprobación en las carreras del área de Ciencias de la Salud de la Universidad Autónoma de Baja California, México

    Directory of Open Access Journals (Sweden)

    Elías Torres Balcázar

    2015-10-01

    Full Text Available Esta investigación explora las causas de reprobación de los estudiantes del segundo semestre de las carreras del área de la Salud (Medicina, Enfermería y Actividad Física y Deportes de la Universidad Autónoma de Baja California, en Ensenada, Mexico. Se identificaron 49 estudiantes reprobados con quienes se realiz6 un diseño investigativo de carácter exploratorio-descriptivo, cuyos resultados permitieron determinar que las principales causas de reprobación se debieron al desempeño academico de los estudiantes, deficiencias en las tecnicas de estudio, poca dedicaci6n a las actividades académicas y el nerviosismo que les provoca enfrentarse a los exámenes. A lo anterior se agrega que la mayor parte no acude al docente para aclarar dudas. A partir de estos resultados, se sugieren diversas estrategias para resolver el problema de reprobación. AbstractThis paper explores causes of failure in students of second semester in Health Program careers (Medicine, Nursing, Physical Activity and Sports at Universidad Autonoma de Baja California, in Ensenada, Mexico. 49 students who failed were identified; they were applied an exploratory and descriptive research design, whose results allowed to determine that the major causes of failure were due to the students’ academic performance; deficient study techniques; little time for academic activities; and stress before term exams. In addition to the aforementioned reasons, most of the students do not ask the teacher to clarify doubts. From these results, a variety of strategies are recommended in order to avoid failures in the Health Program.

  9. Incorporating Cutting Edge Scientific Results from the Margins-Geoprisms Program into the Undergraduate Curriculum, Rupturing Continental Lithosphere Part II: Introducing Euler Poles Using Baja-North America Relative Plate Motion Across the Gulf of California

    Science.gov (United States)

    Loveless, J. P.; Bennett, S. E. K.; Cashman, S. M.; Dorsey, R. J.; Goodliffe, A. M.; Lamb, M. A.

    2014-12-01

    The NSF-MARGINS Program funded a decade of research on continental margin processes. The NSF-GeoPRISMS Mini-lesson Project, funded by NSF-TUES, is designed to integrate the significant findings from the MARGINS program into open-source college-level curriculum. The Gulf of California (GOC) served as the focus site for the Rupturing Continental Lithosphere (RCL) initiative, which addressed several scientific questions: What forces drive rift initiation, localization, propagation and evolution? How does deformation vary in time and space, and why? How does crust evolve, physically and chemically, as rifting proceeds to sea-floor spreading? What is the role of sedimentation and magmatism in continental extension? We developed two weeks of curriculum, including lectures, labs, and in-class activities that can be used as a whole or individually. This component of the curriculum introduces students to the Euler pole description of relative plate motion (RPM) by examining the tectonic interactions of the Baja California microplate and North American plate. The plate boundary varies in rift obliquity along strike, from highly oblique and strike-slip dominated in the south to slightly less oblique and with a larger extensional component in the north. This Google Earth-based exercise provides students with a visualization of RPM using small circle contours of the local direction and magnitude of Baja-North America movement on a spherical Earth. Students use RPM to calculate the fault slip rates on transform, normal, and oblique-slip faults and examine how the varying faulting styles combine to accommodate RPM. MARGINS results are integrated via comparison of rift obliquity with the structural style of rift-related faults around the GOC. We find this exercise to fit naturally into courses about plate tectonics, geophysics, and especially structural geology, given the similarity between Euler pole rotations and stereonet-based rotations of structural data.

  10. Vertebrados terrestres registrados mediante foto-trampeo en arroyos estacionales y cañadas con agua superficial en un hábitat semiárido de Baja California Sur, México Terrestrial vertebrates recorded by camera traps in areas with seasonal streams and creeks of superficial waters in a semiarid habitat of Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Erika Mesa-Zavala

    2012-03-01

    Full Text Available Los cuerpos de agua superficial (CAS permanentes o efímeros (pozas, tinajas, escurrimientos, etc. que se encuentran en depresiones del terreno, como arroyos y cañadas, son soporte fundamental para el ecosistema en zonas áridas. Mediante el uso de cámaras-trampa, en este estudio se identifican especies de vertebrados terrestres silvestres presentes en 4 sitios con agua superficial, en el extremo sur de la sierra El Mechudo, Baja California Sur, y se analiza el uso de los CAS por las especies en los periodos de actividad. En cada sitio se caracterizó el hábitat (topografía, vegetación y agua. Los 4 sitios mostraron diferencias en sus características ambientales. Se identificaron 41 especies de vertebrados terrestres (3 reptiles, 31 aves y 7 mamíferos. Se encontraron también varias especies de murciélagos que no fueron identificadas. La riqueza de especies y frecuencia de visita fue diferente en cada sitio. Con excepción de 3 especies de mamíferos, el horario de actividad fue similar en los 4 sitios. La presente investigación aporta información sobre la importancia de los CAS en zonas semiáridas, describiendo el hábitat, las especies y su comportamiento, elementos básicos para la conservación y manejo de los recursos naturales.Permanent or ephemeral water ponds (puddles, catchments, drains, and so on located on ground depressions, such as streams and creeks, are a fundamental support for ecosystems in dry areas. This study identified the species of native terrestrial vertebrates in 4 sites in the southernmost part of the Sierra El Mechudo, B.C.S., including how such species use these bodies of water based on the periods of species activity. Habitats were characterized in 4 sites (topography, vegetation, and water sources; camera-traps were placed around water ponds from March to October 2007. The 4 sites differed in their environmental characteristics. Overall, there were 41 species of terrestrial vertebrates (3 reptiles, 31

  11. Microstructural and seismic properties of the upper mantle underneath a rifted continental terrane (Baja California): An example of sub-crustal mechanical asthenosphere?

    NARCIS (Netherlands)

    Palasse, L.N.; Vissers, R.L.M.; Paulssen, H.; Basu, A.R.; Drury, M.R.

    2012-01-01

    The Gulf of California rift is a young and active plate boundary that links the San Andreas strike-slip fault system in California to the oceanic spreading system of the East Pacific Rise. The xenolith bearing lavas of the San Quintin volcanic area provide lower crust and upper mantle samples from

  12. Hyperparasitism by the bacteriophage (Caudovirales) infecting Candidatus Xenohaliotis californiensis (Rickettsiales-like prokaryote) parasite of wild abalone Haliotis fulgens and Haliotis corrugata from the Peninsula of Baja California, Mexico.

    Science.gov (United States)

    Cruz-Flores, Roberto; Cáceres-Martínez, Jorge; Muñoz-Flores, Monserrat; Vásquez-Yeomans, Rebeca; Hernández Rodriguez, Mónica; Ángel Del Río-Portilla, Miguel; Rocha-Olivares, Axayácatl; Castro-Longoria, Ernestina

    2016-10-01

    Candidatus Xenohaliotis californiensis (CXc) is a Rickettsiales-like prokaryote that is considered the causal agent of Withering Syndrome (WS), a chronic disease of abalone, from the west coast of North America and it is listed by the International Organization for Animal Health (OIE) as a reportable agent due to its pathogenicity. This bacterium in red abalone Haliotis rufescens, black abalone Haliotis cracherodii, and yellow abalone Haliotis corrugata from California, US and Baja California, Mexico has been found to be infected by a bacteriophage. To date, there is no information on the epizootiology of CXc and its bacteriophage in natural populations of abalone; furthermore, it is unknown if the bacteriophage was also present in CXc infecting blue abalone Haliotis fulgens. The objective of this study was to determine the distribution, prevalence and intensity of CXc, as well as to determine the distribution and prevalence of the bacteriophage and to study interactions between host sex and hyperparasitism in blue abalone and yellow abalone. Tissue samples were obtained from seven localities where the commercial capture of wild abalone is carried out. Samplings were conducted throughout the 2012-2013 capture seasons and a total of 182 blue abalone and 170 yellow abalone were obtained. The prevalence and intensity of CXc and the prevalence of the bacteriophage were determined by histology. The identity of CXc was confirmed by PCR, product sequence analysis and in situ hybridization while the identity of the bacteriophage was corroborated by TEM. The prevalence of CXc infected and uninfected by the bacteriophage was 80% in blue abalone and 62% in yellow abalone. Low infection intensities were found in 86% of blue abalone and 82% of yellow abalone. Infection intensity was significantly higher in undifferentiated yellow abalone. The bacteriophage in CXc showed a prevalence of 22% and 31% in blue abalone and yellow abalone respectively. These results show that CXc and

  13. Juventud, readaptación y sueños truncados: Centro de Diagnóstico para Adolescentes de Tijuana, Baja California

    Directory of Open Access Journals (Sweden)

    María Ruth Velázquez Gutiérrez

    2015-01-01

    Full Text Available la violencia no es un problema de pobreza o marginación; se vincula al deterioro de condi-ciones de vida, desintegración familiar y bajas expectativas de adolescentes y jóvenes en elfuturo.este abandono los orilla a conductas antisociales tipificadas en delincuencia juvenily su reclusión en el sistema penitenciario entijuana.el estudio sitúa en perspectiva las me-didas instrumentadas en elcentro de Diagnóstico paraadolescentes detijuana y sugierecambios en las prácticas de reinserción, por lo menos en lo educativo.el ejercicio se apoya enentrevistas con adolescentes recluidos para entender y explicar mejor este fenómeno.

  14. Learning processes and productive modernization of learning in agriculture from northwestern Mexico: Cases of commercial agriculture of the coast of Hermosillo, Sonora and organic agriculture of the southern zone of Baja California Sur

    Directory of Open Access Journals (Sweden)

    Abel O. Villa Rodríguez

    2013-01-01

    Full Text Available The process of open markets has created import changes in the Mexican agriculture sector, very much noted in the so called crop pattern, the institutional frame that guides the agro–productive commercial relationships and trade organization. The agriculture in the Northwest region, particularly La Costa de Hermosillo in the State of Sonora and southern Baja in Baja Peninsula, shows a big transformation. This corresponds to Global Production Networks (gpn, a vertical integration with intensive extraterritorial interaction resulting in a process of productive escalation that favors; learning and the creation of new competitive capabilities indispensable to comply with high standards in international markets. These capabilities are reflected in improvements in product quality, productive efficiency and the development of new functions for the players involved in the production and trade of produce. It also reflects the transition to more sophisticated productive units where players are located in other territories. This study focuses on analyzing the roll of gpn in the transformation of the agricultural sector in the northwest region of Mexico, particularly the process that took place in modernizing both places.

  15. ¿Por qué son mejores los organismos de agua de Baja California que los de Sonora? Instituciones locales y desempeño de los organismos públicos

    Directory of Open Access Journals (Sweden)

    Nicolás Pineda Pablos

    2012-01-01

    Full Text Available El desempeño de los principales organismos operadores de agua para uso urbano de Baja California, a juzgar por los indicadores de gestión, es superior al de los de Sonora. El objetivo de este artículo es compararlos, y reflexionar sobre las variables explicativas de dicha diferencia. Los dos estados tienen características geográficas y demográficas similares: son fronterizos, su clima es semidesértico y su población comparte la misma cultura y comportamientos. El estudio indaga las causas, y revisa las reglas institucionales que pueden explicar el desempeño diferenciado: la instancia gubernamental responsable del servicio, la duración de los directores, la tarifa, facturación y cobranza, así como la alternancia de partido político en el gobierno local y aquél del cual han emanado los gobiernos responsables del servicio. El estudio concluye que las instituciones importan, y que sus reglas han hecho la diferencia en el desempeño de los organismos de agua de ambas entidades.

  16. Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Mariana Vázquez Hurtado

    2011-03-01

    Full Text Available La almeja chocolate Megapitaria squalida es un recurso pesquero con creciente importancia en el noroeste de México al registrarse un incremento en los volúmenes de captura. Sin embargo, esta pesquería ha observado variaciones importantes en las capturas que podrían estar relacionadas con factores ambientales. Se obtuvieron datos mensuales de producción de M. squalida durante 2002- 2005 y se estimaron series de tiempo de temperatura superficial del mar en la Bahía de La Paz B.C.S. a partir de imágenes mensuales derivadas del sensor MODIS-Aqua. Los resultados indican una relación positiva significativa entre la temperatura superficial del mar y los volúmenes de captura, razón por la cual nuestro trabajo tiene como objetivo estudiar las relaciones entre capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en La Bahía de la Paz, Baja California Sur, México.

  17. Diagnóstico de conocimiento, actitudes y estrategias de equidad de género en servidoras y servidores públicos de primer nivel en Baja California

    Directory of Open Access Journals (Sweden)

    Elizabeth Maier

    2011-01-01

    Full Text Available El presente artículo se basa en el Diagnóstico de conocimientos, actitudes y estrategias de equidad de género de funcionarias y funcionarios de primer nivel en Baja California, estudio cuyo objetivo fue evaluar los conocimientos y las receptividades o resistencias de servidoras y servidores públicos bajacalifornianos sobre la equidad de género; así mismo, se aprecia la transversalidad de la aplicación de la perspectiva de género como guía metodológica de su ejercicio de políticas públicas. La hipótesis implícita al estudio insiste en la necesidad de contar con estrategias de progresiva capacitación en la temática para promover la creciente desautorización del complejo enjambre cultural de inequidad de género que todavía define el acceso diferencial a las oportunidades y beneficios económicos, sociales y políticos en el estado.

  18. Alcances y limitaciones de las políticas sobre el derecho a la no discriminación a escala subnacional en México: el caso de Baja California Sur

    Directory of Open Access Journals (Sweden)

    Gerardo ORDÓÑEZ-BARBA

    2012-01-01

    Full Text Available En este artículo se analiza la situación que guarda la instrumentación de las políticas del derecho a la no discriminación en una de las entidades que, al menos formalmente, se encuentra a la vanguardia en esta materia. Se trata de mostrar los alcances y limitaciones de la legislación de Baja California Sur que alude a los temas de la igualdad, ciudadanía, discriminación y protección a grupos vulnerables; así como de los programas, dependencias y recursos estatales que posibilitan la integración de personas y grupos que padecen discriminación, exclusión o violencia. En elestudio se constata que, a pesar de los avances legislativos, las iniciativas y los recursos involucrados en estas áreas de responsabilidad están aún lejos de ser un instrumento eficaz para el pleno ejercicio del derecho a la no discriminación de los sudcalifornianos.

  19. Water demand studies. [central and southern California regions

    Science.gov (United States)

    Bowden, L. W.; Estes, J. E.; Churchman, C. W.; Johnson, C. W.; Huning, J. R.; Rozelle, K.; Hamilton, J.; Washburn, G.; Tinney, L. R.; Thaman, R. R.

    1973-01-01

    The areas of focus of the Santa Barbara and Riverside groups in conducting water demand studies are the central and southern California regional test sites, respectively. Within each test site, sub-areas have been selected for use in the making of detailed investigations. Within each of these sub-areas an in-depth evaluation is being made as to the capability of remote sensing systems to provide pertinent data relative to water demand phenomena. These more limited sub-areas are: (1) Kern County and the San Joaquin Basin; (2) Chino-Riverside Basin; and (3) the Imperial Valley. Rational for the selection of these subareas included the following: Much of the previous remote sensing research had been conducted in these areas and therefore a great deal of remote sensing imagery and pertinent ground truth for the areas was already available.

  20. Geophysical study of the Clear Lake region, California

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, R.H.

    1975-01-01

    Results of geophysical studies in the Clear Lake region of California, north of San Francisco, have revealed a prominent, nearly circular negative gravity anomaly with an amplitude of more than 25 milligals (mgal) and an areal extent of approximately 250 square miles and, in addition, a number of smaller positive and negative anomalies. The major negative gravity anomaly is closely associated with the Clear Lake volcanic field and with an area characterized by hot springs and geothermal fields. However, the anomaly cannot be explained by mapped surface geologic features of the area. Aeromagnetic data in the Clear Lake region show no apparent correlation with the major negative gravity anomaly; the local magnetic field is affected principally by serpentine. An electrical resistivity low marks the central part of the gravity minimum, and a concentration of earthquake epicenters characterizes the Clear Lake volcanic field area. The primary cause of the major negative gravity anomaly is believed to be a hot intrusive mass, possibly a magma chamber, that may underlie the Clear Lake volcanic field and vicinity. This mass may serve as a source of heat for the geothermal phenomena in the area. Other smaller gravity anomalies in the Clear Lake region are apparently caused by near-surface geologic features, including relatively dense units of the Franciscan Formation and less dense Cenozoic sedimentary and volcanic rock units.

  1. Caracterización espacial y biogeográfica de las asociaciones de macroalgas de Bahía del Rincón,Baja California Sur,México

    Directory of Open Access Journals (Sweden)

    R Riosmena-Rodríguez

    2005-06-01

    Full Text Available Se caracterizó la flora marina de la zona de Bahía del Rincón -La Rivera por medio de prospecciones intensivas en diferentes localidades a varias profundidades. Además, se realizó un análisis intenso de la literatura y por este mismo medio la determinación de las afinidades geográficas de las especies. En total se encontraron 72 especies, donde la mayor proporción (62% correspondió a las algas rojas. En el caso de las afinidades biogeográficas se observó que la mayor proporción varió en función de la división, donde para algas cafés las predominantes fueron de naturaleza tropical/ endémica y para las algas rojas fueron las templadas/ cosmopolitas. Espacialmente se encontró una alta similitud entre las zonas someras estudiadas más no así entre las someras y profundas donde existen diferencias significativas. En el caso de la zona intermareal se determinaron diferencias significativas con áreas submareales y entre sitios de la zona somera y profunda basados en las abundancias de los principales taxa. Con base en los resultados se sugiere que existen diferencias verticales en reclutamiento y desarrollo de las poblaciones en relación a su distribuciónSpatial and biogeographic characterization of macroalgal assemblages from Bahía del Rincón, Baja California Sur, Mexico.Macroalgal studies in Baja California Sur have dealt mainly with occurrence and seasonality, but some areas are poorly known even for these basic data. Bahía del Rincón-La Rivera is an important high-productivity fisheries area where coastal infrastructure development is under way. A spatial characterization of the marine flora from Bahía del Rincón-La Rivera was done by intensive sampling at different depths and localities with skin and SCUBA diving. At least 500m² were surveyed in each site. Additionally, quantitative sampling was done in ten random 25 cm² quadrates per site. In the intertidal section, density and cover estimates were used. We also

  2. Geochemical Relationships between Volcanic and Plutonic Upper to Mid Crustal Exposures of the Rosario Segment, Alisitos Arc (Baja California, Mexico): An Outstanding Field Analog to the Izu-Bonin-Mariana Arc

    Science.gov (United States)

    Morris, R.; DeBari, S. M.; Busby, C. J.; Medynski, S.

    2015-12-01

    Exposed paleo-arcs, such as the Rosario segment of the Cretaceous Alisitos Arc in Baja California, Mexico, provide an opportunity to explore the evolution of arc crust through time. Remarkable 3-D exposures of the Rosario segment record crustal generation processes in the volcanic rocks and underlying plutonic rocks. In this study, we explore the physical and geochemical connection between the plutonic and volcanic sections of the extensional Alisitos Arc, and elucidate differentiation processes responsible for generating them. These results provide an outstanding analog for extensional active arc systems, such as the Izu-Bonin-Mariana (IBM) Arc. Upper crustal volcanic rocks have a coherent stratigraphy that is 3-5 km thick and ranges in composition from basalt to dacite. The most felsic compositions (70.9% SiO2) are from a welded ignimbrite unit. The most mafic compositions (51.5% SiO2, 3.2% MgO) are found in basaltic sill-like units. Phenocrysts in the volcanic units include plagioclase +/- amphibole and clinopyroxene. The transition to deeper plutonic rocks is clearly an intrusive boundary, where plutonic units intrude the volcanic units. Plutonic rocks are dominantly a quartz diorite main phase with a more mafic, gabbroic margin. A transitional zone is observed along the contact between the plutonic and volcanic rocks, where volcanics have coarsely recrystallized textures. Mineral assemblages in the plutonic units include plagioclase +/- quartz, biotite, amphibole, clinopyroxene and orthopyroxene. Most, but not all, samples are low K. REE patterns are relatively flat with limited enrichment. Normalization diagrams show LILE enrichment and HFSE depletion, where trends are similar to average IBM values. We interpret plutonic and volcanic units to have similar geochemical relationships, where liquid lines of descent show the evolution of least to most evolved magma types. We provide a model for the formation and magmatic evolution of the Alisitos Arc.

  3. Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Mariana Vázquez Hurtado

    2011-03-01

    Full Text Available La almeja chocolate Megapitaria squalida es un recurso pesquero con creciente importancia en el noroeste de México al registrarse un incremento en los volúmenes de captura. Sin embargo, esta pesquería ha observado variaciones importantes en las capturas que podrían estar relacionadas con factores ambientales. Se obtuvieron datos mensuales de producción de M. squalida durante 2002- 2005 y se estimaron series de tiempo de temperatura superficial del mar en la Bahía de La Paz B.C.S. a partir de imágenes mensuales derivadas del sensor MODIS-Aqua. Los resultados indican una relación positiva significativa entre la temperatura superficial del mar y los volúmenes de captura, razón por la cual nuestro trabajo tiene como objetivo estudiar las relaciones entre capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en La Bahía de la Paz, Baja California Sur, México.Megapitaria squalida (Bivalvia: Veneridae fishery landings and temperature relationship in Bahía de la Paz, México. The clam Megapitaria squalida is a fishing resource with increasing importance in Northwestern Mexico. Nevertheless, this fishery has shown important variations that could be related to environmental factors. To assess this, monthly landings of M. squalida were analyzed during 2002-2005 for Bahía de La Paz, B.C.S., and were related with monthly time series of sea surface temperature, derived from MODIS-Aqua Sensor. The results showed a positive and significant relationship between sea surface temperature and clam landings. The likely impact of anomalous conditions of sea temperature on this resource is discussed. Rev. Biol. Trop. 59 (1: 151-157. Epub 2011 March 01.

  4. Capacidad de carga turÍstica como base para el manejo sustentable de actividades ecoturísticas en Unidades de Manejo Ambiental (UMA de Baja California Sur (BCS

    Directory of Open Access Journals (Sweden)

    Reyna Ibañez Pérez

    2016-01-01

    Full Text Available Existen zonas ejidales con UMA ́s, que desean incursionar en el turismo alternativo; tal es el caso del Nuevo Centro Poblacional Ejidal (NCPE, Ley Federal de Aguas Número 3, que se extiende a tres municipios de Baja California Sur (BCS, posee una UMA y se destaca por buscar opciones para reactivar su economía. En este trabajo se presentan los resultados de un estudio de Capacidad de Carga Turística (CCT, realizada en dos senderos de ese ejido, mediante la aplicación de la metodología de Cifuentes, que busca establecer el número máximo de visitas que puede recibir un área con base en sus condiciones físicas, biológicas y de manejo; cuya estimación, requirió de la revisión de censos de flora y fauna, de información geológica, climatológica, geográfica, ambiental, social, económica, turística, así como trabajo de campo. Los resultados indican que, en el NCPE, Ley Federal de Aguas Número 3, existen dos senderos con potencialidad turística para los cuales, se ha estimado una Capacidad de Carga Efectiva (CCE de 18 visitantes/día para el sendero del arroyo El Camarón y de 10 visitantes/día sendero del arroyo El Saucito. Las cifras anteriores, son un referente para el establecimiento de medidas de control de las visitas en ambos senderos

  5. Crecimiento económico, desarrollo sustentable y turismo: Una aproximación del posicionamiento de Baja California Sur (BCS en el Barómetro de Sustentabilidad

    Directory of Open Access Journals (Sweden)

    Reyna Ibáñez Pérez

    2011-01-01

    Full Text Available Uno de los mayores anhelos de toda sociedad es alcanzar un nivel económico elevado; otro es el de tener la oportunidad de disfrutar eternamente de los servicios proporcionados por la madre naturaleza. Sin embargo, las tendencias indican que se experimenta un deterioro importante en el ambiente, a la par, de una elevada concentración de pobreza. Esto, aunado a la dependencia que algunas entidades y países han desarrollado en relación a actividades -como la turística- se ha convertido en una de las preocupaciones centrales de los gobiernos, el establecer mediciones para determinar si las pautas de crecimiento y desarrollo, van acorde con el cuidado del ambiente y el bienestar de las personas. Por ello, dentro de este artículo se analizan la evolución del crecimiento económico y posicionamiento de Baja California Sur (BCS -un estado con importante actividad turística- en el Barómetro de Sustentabilidad. En la introducción, se aprecia la evolución del concepto de crecimiento y desarrollo, para continuar con la caracterización de la zona de estudio. Posteriormente, se detalla la metodología empleada. Enseguida, se estudia la situación actual del sector turístico en BCS y la evolución del crecimiento y desarrollo económico. En el análisis de resultados, se describen los factores que ubican a BCS en un nivel Medio de sustentabilidad. Finalmente, se presentan algunas reflexiones en relación a los retos que en materia de turismo, crecimiento económico, desarrollo sustentable afronta BCS.

  6. California Wintertime Precipitation in Regional and Global Climate Models

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, P M

    2009-04-27

    In this paper, wintertime precipitation from a variety of observational datasets, regional climate models (RCMs), and general circulation models (GCMs) is averaged over the state of California (CA) and compared. Several averaging methodologies are considered and all are found to give similar values when model grid spacing is less than 3{sup o}. This suggests that CA is a reasonable size for regional intercomparisons using modern GCMs. Results show that reanalysis-forced RCMs tend to significantly overpredict CA precipitation. This appears to be due mainly to overprediction of extreme events; RCM precipitation frequency is generally underpredicted. Overprediction is also reflected in wintertime precipitation variability, which tends to be too high for RCMs on both daily and interannual scales. Wintertime precipitation in most (but not all) GCMs is underestimated. This is in contrast to previous studies based on global blended gauge/satellite observations which are shown here to underestimate precipitation relative to higher-resolution gauge-only datasets. Several GCMs provide reasonable daily precipitation distributions, a trait which doesn't seem tied to model resolution. GCM daily and interannual variability is generally underpredicted.

  7. Daño genético y exposición a plaguicidas en trabajadores agrícolas del Valle de San Quintín, Baja California, México Genetic damage and exposure to pesticides among agricultural workers from Valle de San Quintín, Baja California, México Danos genéticos e exposição a pesticidas em trabalhadores agrícolas do Vale San Quintin, Baixa California, México

    Directory of Open Access Journals (Sweden)

    J. Claudia Leyva Aguilera

    2012-12-01

    Full Text Available Diferentes estudios muestran la capacidad de los plaguicidas para inducir daño genético (DG con diversos efectos en la salud. En el presente trabajo se estudia la genotoxicidad en residentes del valle agrícola de San Quintín, Baja California, México (VSQ. El objetivo fue determinar si la exposición laboral y ambiental a plaguicidas en la región del VSQ es un factor de DG y explorar si las mujeres son más vulnerables a dicho efecto. Se aplicó un cuestionario a 88 residentes del VSQ para determinar los factores de inclusión y exclusión del estudio, 40 aceptaron participar, 25 expuestos ocupacionalmente a plaguicidas y 15 ambientalmente expuestos, con similar número de hombres y mujeres. Todos los participantes firmaron un consentimiento informado. Se utilizó la técnica de micronúcleos (MN por bloqueo de la citocinesis en sangre periférica para evaluar el DG con la frecuencia de MN y Puentes de Cromatina en 1000 células binucleadas (CBN; se exploró la correlación del DG con el tiempo de exposición ocupacional a plaguicidas. Los hombres ambientalmente expuestos tuvieron menos DG que las mujeres con medias de MN de 8,1 (±1,83 y 13,1 (±1,7 respectivamente; en cambio, la exposición laboral afectó a los dos sexos: los hombres tuvieron una media de MN igual a 15,9 (±2,9 y en las mujeres fue 18,1 (±1,7. Se concluye que la exposición laboral a plaguicidas es un factor de DG, las mujeres mostraron mayor vulnerabilidad al DG. El tiempo de exposición laboral se relaciona directamente con el aumento del número de MN.Various studies have shown the ability of pesticides to induce genetic damage (GD that can cause health effects. In the present work, a genotoxicological study was conducted monitoring residents from the agricultural region of the San Quintin Valley (SQV, Baja California, Mexico. The objective was to determine if occupational and environmental exposure to pesticides in the region of the SQV is a factor in GD, and to

  8. Curie Depth Analysis of the Salton Sea Region, Southern California

    Science.gov (United States)

    Mickus, Kevin; Hussein, Musa

    2016-02-01

    Aeromagnetic data were analyzed to determine the bottom of magnetic bodies that might be related to the Curie point depth (CPD) by 2D spectral and 3D inversion methods within the Salton Trough and the surrounding region in southern California. The bottom of the magnetic bodies for 55 × 55 km windows varied in depth between 11 and 23 km in depth using 2D spectral methods. Since the 55 × 55 km square window may include both shallow and deep source, a 3D inversion method was used to provide better resolution of the bottom of the magnetic bodies. The 3D models indicate the depth to the bottom of the magnetic bodies varied between 5 and 23 km. Even though both methods produced similar results, the 3D inversion method produced higher resolution of the CPD depths. The shallowest depths (5-8 km) occur along and west of the Brawley Seismic Zone and the southwestern portion of the Imperial Valley. The source of these shallow CPD values may be related to geothermal systems including hydrothermal circulation and/or partially molten material. Additionally, shallow CPD depths (7-12 km) were found in a northwest-trending zone in the center of the Salton Trough. These depths coincide with previous seismic analyses that indicated a lower crustal low velocity region which is believed to be caused by partially molten material. Lower velocity zones in several regions may be related to fracturing and/or hydrothermal fluids. If the majority of these shallow depths are related to temperature, they are likely associated with the CPD, and the partially molten material extends over a wider zone than previously known. Greater depths within the Salton Trough coincide with the base of basaltic material and/or regions of intense metamorphism intruded by mafic material in the middle/lower crust.

  9. Estructura de la comunidad y asociación de las aves acuáticas con la heterogeneidad espacial del complejo lagunar Bahía Magdalena-Almejas, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Bulmara Zárate-Ovando

    2008-03-01

    Full Text Available Para probar la hipótesis que la heterogeneidad espacial determina la diversidad de aves acuáticas en un humedal costero, comparamos la densidad, diversidad y composición de especies de aves acuáticas entre habitats y otras unidades de paisaje del complejo Bahía Magdalena-Almejas, Baja California Sur, México. Se realizaron censos de aves acuáticas en 329 segmentos de habitat de la línea de costa interna del complejo lagunar, desde febrero 2002 hasta febrero 2003. La densidad de aves fue mayor en invierno y otoño en las tres lagunas del área de estudio; de las zonas, la densidad fue mayor en la costa insular; y de los habitats en playa arenosa y dunas pero en los pocos segmentos de sustrato antrópico la densidad fue alta. La diversidad fue significativamente mayor en otoño; en Canal Santo Domingo; en la costa peninsular; y de los habitats en manglar-dunas y manglar. La modificación del habitat natural costero y el disturbio por tránsito de embarcaciones no tuvieron influencia en la densidad o diversidad de aves acuáticas, pero la riqueza acumulada mayor ocurrió en las costas bien conservadas y sin disturbio. El análisis de la composición de especies mostró diferencias entre las asociaciones de Canal Santo Domingo y Bahía Magdalena. El ambiente pelágico y el manglar tuvieron diferencia mayor en la composición de especies con respecto a las asociaciones de los demás habitats, tales diferencias en elencos de especies por habitat sugieren que la comunidad de aves está estructurada de acuerdo a los recursos naturales disponibles de las lagunas, zonas y habitats, en relación con la complejidad estructural de las unidades de paisaje. Las condiciones ecológicas del complejo lagunar ocasionan que las aves acuáticas piscívoras sean el grupo dominante de esta comunidad.Community structure and association of waterbirds with spatial heterogeneity in the Bahía Magdalena-Almejas wetland complex, Baja California Sur, Mexico. To test

  10. Canales espaciales de articulación en el corredor turístico Los Cabos, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Álvaro López-López

    2002-01-01

    Full Text Available El corredor de Los Cabos es uno de los espacios turísticos más dinámicos de México que, en su articulación territorial, ha generado canales que muestran una situación contrastante: las ligas que se mantienen hacia la costa occidental de Estados Unidos y, dentro del corredor, las relacionadas con los espacios turísticos, son altamente eficientes; en contraste, la red de infraestructura, transportes y comunicaciones interna que se asocia con la población local y regional, presenta aún serias deficiencias.

  11. Canales espaciales de articulación en el corredor turístico Los Cabos, Baja California Sur, México

    OpenAIRE

    Álvaro López-López; Álvaro Sánchez-Crispín

    2002-01-01

    El corredor de Los Cabos es uno de los espacios turísticos más dinámicos de México que, en su articulación territorial, ha generado canales que muestran una situación contrastante: las ligas que se mantienen hacia la costa occidental de Estados Unidos y, dentro del corredor, las relacionadas con los espacios turísticos, son altamente eficientes; en contraste, la red de infraestructura, transportes y comunicaciones interna que se asocia con la población local y regional, present...

  12. Hydrologic model of the Modesto Region, California, 1960-2004

    Science.gov (United States)

    Phillips, Steven P.; Rewis, Diane L.; Traum, Jonathan A.

    2015-01-01

    Strategies for managing water supplies and groundwater quality in the Modesto region of the eastern San Joaquin Valley, California, are being formulated and evaluated by the Stanislaus and Tuolumne Rivers Groundwater Basin Association. Management issues and goals in the basin include an area in the lower part of the basin that requires drainage of the shallow water table to sustain agriculture, intra- and inter-basin migration of poor-quality groundwater, and efficient management of surface and groundwater supplies. To aid in the evaluation of water-management strategies, the U.S. Geological Survey and the Stanislaus and Tuolumne Rivers Groundwater Basin Association have developed a hydrologic model that simulates monthly groundwater and surface-water flow as governed by aquifer-system properties, annual and seasonal variations in climate, surface-water flow and availability, water use, and land use. The model was constructed by using the U.S. Geological Survey groundwater-modeling software MODFLOW-OWHM with the Farm Process.

  13. Evaluación del impacto socioeconómico de la Reserva de la Biosfera Alto Golfo de California y Delta del Río Colorado en la actividad pesquera ribereña de San Felipe, Baja California, México

    Directory of Open Access Journals (Sweden)

    Carlos Israel Vázquez León

    2010-01-01

    Full Text Available Desde 1993 las comunidades de Puerto Peñasco y Golfo de Santa Clara, Sonora, y San Felipe, Baja California, en México, están vinculadas por la Reserva de la Biosfera Alto Golfo de California y Delta del Río Colorado; creada para proteger varias especies endémicas, entre ellas al mamífero conocido como vaquita marina (Phocoenasinus y la totoaba (Totoaba macdonaldii.Aquí se analiza el efecto socioeconómico que en la pesca de San Felipe tuvo en 1994 y 2002 la creación de la reserva; concebida como un arreglo institucional de regulación pesquera, centrada en la protección ambiental y ecológica. La conclusión general es que deben incorporarse consideraciones socioeconómicas en el diseño de indicadores de eficiencia y evaluación para el éxito de la reserva territorial.

  14. Geothermal regimes of the Clearlake region, northern California

    Energy Technology Data Exchange (ETDEWEB)

    Amador, M. [ed.; Burns, K.L.; Potter, R.M.

    1998-06-01

    The first commercial production of power from geothermal energy, at The Geysers steamfield in northern California in June 1960, was a triumph for the geothermal exploration industry. Before and since, there has been a search for further sources of commercial geothermal power in The Geysers--Clear Lake geothermal area surrounding The Geysers. As with all exploration programs, these were driven by models. The models in this case were of geothermal regimes, that is, the geometric distribution of temperature and permeability at depth, and estimates of the physical conditions in subsurface fluids. Studies in microseismicity and heat flow, did yield geophysical information relevant to active geothermal systems. Studies in stable-element geochemistry found hiatuses or divides at the Stoney Creek Fault and at the Collayomi Fault. In the region between the two faults, early speculation as to the presence of steamfields was disproved from the geochemical data, and the potential existence of hot-water systems was predicted. Studies in isotope geochemistry found the region was characterized by an isotope mixing trend. The combined geochemical data have negative implications for the existence of extensive hydrothermal systems and imply that fluids of deep origin are confined to small, localized systems adjacent to faults that act as conduits. There are also shallow hot-water aquifers. Outside fault-localized systems and hot-water aquifers, the area is an expanse of impermeable rock. The extraction of energy from the impermeable rock will require the development and application of new methods of reservoir creation and heat extraction such as hot dry rock technology.

  15. Daño genético y exposición a plaguicidas en trabajadores agrícolas del Valle de San Quintín, Baja California, México

    Directory of Open Access Journals (Sweden)

    Erika Zúñiga Violante

    2012-12-01

    Full Text Available Diferentes estudios muestran la capacidad de los plaguicidas para inducir daño genético (DG con diversos efectos en la salud. En el presente trabajo se estudia la genotoxicidad en residentes del valle agrícola de San Quintín, Baja California, México (VSQ. El objetivo fue determinar si la exposición laboral y ambiental a plaguicidas en la región del VSQ es un factor de DG y explorar si las mujeres son más vulnerables a dicho efecto. Se aplicó un cuestionario a 88 residentes del VSQ para determinar los factores de inclusión y exclusión del estudio, 40 aceptaron participar, 25 expuestos ocupacionalmente a plaguicidas y 15 ambientalmente expuestos, con similar número de hombres y mujeres. Todos los participantes firmaron un consentimiento informado. Se utilizó la técnica de micronúcleos (MN por bloqueo de la citocinesis en sangre periférica para evaluar el DG con la frecuencia de MN y Puentes de Cromatina en 1000 células binucleadas (CBN; se exploró la correlación del DG con el tiempo de exposición ocupacional a plaguicidas. Los hombres ambientalmente expuestos tuvieron menos DG que las mujeres con medias de MN de 8,1 (±1,83 y 13,1 (±1,7 respectivamente; en cambio, la exposición laboral afectó a los dos sexos: los hombres tuvieron una media de MN igual a 15,9 (±2,9 y en las mujeres fue 18,1 (±1,7. Se concluye que la exposición laboral a plaguicidas es un factor de DG, las mujeres mostraron mayor vulnerabilidad al DG. El tiempo de exposición laboral se relaciona directamente con el aumento del número de MN.

  16. Composición química y precursores de ácidos vaccénico y ruménico en especies forrajeras en Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Eduardo Alberto Toyes-Vargas

    2013-01-01

    Full Text Available Los rumiantes pequeños que pastorean la vegetación nativa seleccionan su dieta a partir de una amplia variedad de especies vegetales, que difieren en su contenido y disponibilidad de nutrientes durante el año, y son fuente importante de nutrientes. El objetivo del estudio fue determinar y comparar la composición bioquímica de especies forrajeras asociadas al agostadero de Baja California Sur. Las especies evaluadas fueron huizache, mezquite, palo fierro, palo verde y vinorama, así como alfalfa henificada. Se cuantificó el contenido de materia seca, proteína cruda, lípidos totales, fibra cruda, cenizas, extracto libre de nitrógeno y energía bruta, así como la concentración de ácido linoléico, ácido -linolénico y ácidos grasos poliinsaturados ARA, EPA y DHA. Los resultados muestran que el palo verde y el mezquite presentaron un contenido mayor de proteína cruda. El huizache mostró la concentración mayor de lípidos totales, seguido de palo verde y mezquite. Huizache y alfalfa henificada presentaron las concentraciones mayores de ácido linoleico; mientras que palo verde alcanzó los niveles más altos de ácido alfa linolénico, seguido por palo fierro y alfalfa henificada. Palo verde, palo fierro y alfalfa henificada obtuvieron concentraciones mayores de ácidos grasos poliinsaturados. El uso de los forrajes de agostadero en la alimentación de los rumiantes es una alternativa que podrá modificar las proporciones de los ácidos grasos de la leche dado el contenido del ácido oleico, linoléico y linolénico, precursores del ácido vaccénico y ruménico y ácidos grasos poliinsaturados de la serie omega 3 como el EPA y el DHA.

  17. A regional soil and sediment geochemical study in northern California

    International Nuclear Information System (INIS)

    Goldhaber, Martin B.; Morrison, Jean M.; Holloway, JoAnn M.; Wanty, Richard B.; Helsel, Dennis R.; Smith, David B.

    2009-01-01

    Regional-scale variations in soil geochemistry were investigated in a 20,000-km 2 study area in northern California that includes the western slope of the Sierra Nevada, the southern Sacramento Valley and the northern Coast Ranges. Over 1300 archival soil samples collected from the late 1970s to 1980 in El Dorado, Placer, Sutter, Sacramento, Yolo and Solano counties were analyzed for 42 elements by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry following a near-total dissolution. These data were supplemented by analysis of more than 500 stream-sediment samples from higher elevations in the Sierra Nevada from the same study site. The relatively high-density data (1 sample per 15 km 2 for much of the study area) allows the delineation of regional geochemical patterns and the identification of processes that produced these patterns. The geochemical results segregate broadly into distinct element groupings whose distribution reflects the interplay of geologic, hydrologic, geomorphic and anthropogenic factors. One such group includes elements associated with mafic and ultramafic rocks including Cr, Ni, V, Co, Cu and Mg. Using Cr as an example, elevated concentrations occur in soils overlying ultramafic rocks in the foothills of the Sierra Nevada (median Cr = 160 mg/kg) as well as in the northern Coast Ranges. Low concentrations of these elements occur in soils located further upslope in the Sierra Nevada overlying Tertiary volcanic, metasedimentary and plutonic rocks (granodiorite and diorite). Eastern Sacramento Valley soil samples, defined as those located east of the Sacramento River, are lower in Cr (median Cr = 84 mg/kg), and are systematically lower in this suite compared to soils from the west side of the Sacramento Valley (median Cr = 130 mg/kg). A second group of elements showing a coherent pattern, including Ca, K, Sr and REE, is derived from relatively silicic rocks types. This group occurs at elevated

  18. A regional soil and sediment geochemical study in northern California

    Science.gov (United States)

    Goldhaber, M.B.; Morrison, J.M.; Holloway, J.M.; Wanty, R.B.; Helsel, D.R.; Smith, D.B.

    2009-01-01

    Regional-scale variations in soil geochemistry were investigated in a 20,000-km2 study area in northern California that includes the western slope of the Sierra Nevada, the southern Sacramento Valley and the northern Coast Ranges. Over 1300 archival soil samples collected from the late 1970s to 1980 in El Dorado, Placer, Sutter, Sacramento, Yolo and Solano counties were analyzed for 42 elements by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry following a near-total dissolution. These data were supplemented by analysis of more than 500 stream-sediment samples from higher elevations in the Sierra Nevada from the same study site. The relatively high-density data (1 sample per 15 km2 for much of the study area) allows the delineation of regional geochemical patterns and the identification of processes that produced these patterns. The geochemical results segregate broadly into distinct element groupings whose distribution reflects the interplay of geologic, hydrologic, geomorphic and anthropogenic factors. One such group includes elements associated with mafic and ultramafic rocks including Cr, Ni, V, Co, Cu and Mg. Using Cr as an example, elevated concentrations occur in soils overlying ultramafic rocks in the foothills of the Sierra Nevada (median Cr = 160 mg/kg) as well as in the northern Coast Ranges. Low concentrations of these elements occur in soils located further upslope in the Sierra Nevada overlying Tertiary volcanic, metasedimentary and plutonic rocks (granodiorite and diorite). Eastern Sacramento Valley soil samples, defined as those located east of the Sacramento River, are lower in Cr (median Cr = 84 mg/kg), and are systematically lower in this suite compared to soils from the west side of the Sacramento Valley (median Cr = 130 mg/kg). A second group of elements showing a coherent pattern, including Ca, K, Sr and REE, is derived from relatively silicic rocks types. This group occurs at elevated

  19. Humanitarismo, redención y ciencia médica en Nueva España: El expediente de salud pública para frenar la extinción de indios en la Baja California (1797-1805 Humanitarianism, Redemption and Medical Science in New Spain: The Public Health Plan to Halt the Extinction of Indians in Baja California (1797-1805

    Directory of Open Access Journals (Sweden)

    Francisco Altable

    2011-08-01

    Full Text Available A partir de la descripción de los diversos momentos de la puesta en marcha de un programa médico diseñado para revertir el largo proceso de decadencia poblacional de los indios de la península de California, se pone a la vista lo que podría denominarse el humanitarismo político de la corona española, proyectado en el debate habido entre las perspectivas religiosa y científica en torno a la extinción de los indios. El artículo explica las causas de lo que se denomina aquí la utopía de la sanación de los californios y ofrece una interpretación que varía de las concepciones relativas a la consabida incapacidad génica de los indios para sobrevivir a los contagios, a los errores e imposiciones del proceso de aculturación y a otros factores adversos a la existencia indígena. Se concluye que el fracaso del programa médico en cuestión contribuyó a la frustración de las expectativas colonizadoras, humanitarias, religiosas y modernizadoras del régimen borbónico.On the basis of a description of various moments in the implementation of a medical program to reverse the long population decline of Indians in the California península, what could be called the political humanitarianism of the Spanish Crown emerged, projected onto the debate between the religious and scientific perspectives regarding the extinction of the Indians. The árdele explains the causes of what is called the Utopia of the Californians' healing, offering an interpretation that ranges from relative conceptions to the Indians' well-known genetic capacity to survive the infections, errors and impositions of the acculturation process and other factors that adversely affect indigenous existence. It concludes that the failure of the medical program in question contributed to the frustration of the colonizing, humanitarian, religious and modernizing expectations of the Bourbon regime.

  20. Local district constituencies and representation inequality. Baja California’s situation, 1992-2004

    Directory of Open Access Journals (Sweden)

    Leopoldo Martínez Herrera

    2008-01-01

    Full Text Available Regardless of the reformist advancements of the election system, there are still unresolved issues. In the case of Mexico and in the midst of a debate on our transition process we place the issue of district overrepresentation, wich by generating multiple effects configures a point of deep discussion thus concerning the system of representation, the integration of the house of representatives, the parties system and above all it puts a debate on the following premise: "a vote per citizen", that is, the principle of equalness in democracy, which translated to the field of elections means, as Bovero stated, assigning an equal-valve decition quota to each citizen. In the case of Baja California, our purpose is to demonstrate that the issues related to the deficient district representation, the integration of the parties within the house of representatives, and as a consequence the athrophy of the parties system continue to be an actual problem on this transition process that haven't been able to trascend the margins of regional and local dynamics of politics and power. This study includes an analysis of territorial-demography of legislative representation of Baja California, taking as a reference all research undertaken on similar phenomena by Diego Reynoso, FLACSO researcher.

  1. California Bioregions

    Data.gov (United States)

    California Natural Resource Agency — California regions developed by the Inter-agency Natural Areas Coordinating Committee (INACC) were digitized from a 1:1,200,000 California Department of Fish and...

  2. Water appropriation and ecosystem stewardship in the Baja desert

    OpenAIRE

    de las Heras Alejandro; Rodriguez Mario A.; Islas-Espinoza Marina

    2014-01-01

    The UNESCO San Francisco Rock Paintings polygon within El Vizcaino Biosphere Reserve in the Baja California Peninsula derives its moisture from the North American monsoon. There, ranchers have depended on the desert since the 18th century. More recently, the desert has depended on the environmental stewardship of the ranchers who have allayed mining exploitation and archaeological looting. Using a Rapid Assessment Procedure (RAP), climate data, and geographical informa...

  3. Geothermal systems of the Mono Basin-Long Valley region, eastern California and western Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, C.T.; Flynn, T.; Chapman, R.H.; Trexler, D.T.; Chase, G.R.; Bacon, C.F.; Ghusn, G. Jr.

    1985-01-01

    The region that includes Mono Basin, Long Valley, the Bridgeport-Bodie Hills area, and Aurora, in eastern California and western Nevada was studied to determine the possible causes and interactions of the geothermal anomalies in the Mono Basin-Long Valley region as a whole. A special goal of the study was to locate possible shallow bodies of magma and to determine their influence on the hydrothermal systems in the region. (ACR)

  4. Southwest Regional Climate Hub and California Subsidiary Hub assessment of climate change vulnerability and adaptation and mitigation strategies

    Science.gov (United States)

    Emile Elias; Caiti Steele; Kris Havstad; Kerri Steenwerth; Jeanne Chambers; Helena Deswood; Amber Kerr; Albert Rango; Mark Schwartz; Peter Stine; Rachel Steele

    2015-01-01

    This report is a joint effort of the Southwest Regional Climate Hub and the California Subsidiary Hub (Sub Hub). The Southwest Regional Climate Hub covers Arizona, California, Hawai‘i and the U.S. affiliated Pacific Islands, Nevada, New Mexico, and Utah and contains vast areas of western rangeland, forests, and high-value specialty crops (Figure 1). The California Sub...

  5. Survival of fishers in the southern Sierra Nevada region of California

    Science.gov (United States)

    Richard A. Sweitzer; Craig M. Thompson; Rebecca E. Green; Reginald H. Barrett; Kathryn L. Purcell

    2015-01-01

    Fishers in the western United States were recently proposed for listing under the U.S. Endangered Species Act because of concerns for loss of suitable habitat and evidence of a diversity of mortality risks that reduce survival. One of 2 remnant populations of fishers in California is in the southern Sierra Nevada region, where we studied them at 2 research sites in the...

  6. Subsurface imaging in a sector of Cerro Prieto transform fault near to pull-apart basin, Mexicali Valley, Baja California, Mexico, based on crooked lines 2D seismic reflection.

    Science.gov (United States)

    Mares-Agüero, M. A.; González-Escobar, M.; Arregui, S.

    2016-12-01

    In the transition zone between San Andres continental transformation system and the coupled transform faults system and rifting of Gulf of California is located the Cerro Prieto pull-apart basin delimitated by Imperial fault (northeast) and Cerro Prieto fault (CPF) (southwest), this last, is the limit west of Cerro Prieto geothermic field (CPGF). Crooked lines 2D seismic reflection, covering a portion near the intersection of CPF and CPGF are processed and interpreted. The seismic data were obtained in the early 80's by Petróleos Mexicanos (PEMEX). By decades, technical and investigation works in Cerro Prieto geothermic field and its vicinity had mapped faults at several depths but do not stablish a clear limit where this faults and CPF interact due the complex hydrothermal effects imaging the subsurface. The profiles showing the presence of a zone of uplift effect due to CPF. Considering the proximity of the profiles to CPF, it is surprising almost total absence of faults. A strong reflector around 2 km of depth, it is present in all profiles. This seismic reflector is considered a layer of shale, result of the correlation with a well located in the same region.

  7. Urban-wildland fires: how California and other regions of the US can learn from Australia

    International Nuclear Information System (INIS)

    Stephens, Scott L; Moritz, Max A; Adams, Mark A; Handmer, John; Kearns, Faith R; Leicester, Bob; Leonard, Justin

    2009-01-01

    Most urban-wildland interface (UWI) fires in California and the other regions of the US are managed in a similar fashion: fire agencies anticipate the spread of fire, mandatory evacuations are ordered, and professional fire services move in and attempt to suppress the fires. This approach has not reduced building losses in California. Conversely, losses and the associated suite of environmental impacts, including reduced air quality, have dramatically increased over the last three decades. In contrast to California, Australia has developed a more effective 'Prepare, stay and defend, or leave early' policy. Using this approach, trained residents decide whether they will stay and actively defend their well-prepared property or leave early before a fire threatens them. Australian strategies have the distinct advantage of engaging and preparing those most affected by such fires: homeowners. Investing more in fire suppression alone, the common response after large UWI fires in California, will not reduce losses. US society has attempted to accommodate many of the natural hazards inherent to the landscapes that we inhabit; by examining the Australian model, we may approach a more sustainable coexistence with fire as well. However, it should be noted that some California communities are so vulnerable that a 'Prepare and leave early' strategy may be the only option.

  8. Characterization of the Deep Water Surface Wave Variability in the California Current Region

    Science.gov (United States)

    Villas Bôas, Ana B.; Gille, Sarah T.; Mazloff, Matthew R.; Cornuelle, Bruce D.

    2017-11-01

    Surface waves are crucial for the dynamics of the upper ocean not only because they mediate exchanges of momentum, heat, energy, and gases between the ocean and the atmosphere, but also because they determine the sea state. The surface wave field in a given region is set by the combination of local and remote forcing. The present work characterizes the seasonal variability of the deep water surface wave field in the California Current region, as retrieved from over two decades of satellite altimetry data combined with wave buoys and wave model hindcast (WaveWatch III). In particular, the extent to which the local wind modulates the variability of the significant wave height, peak period, and peak direction is assessed. During spring/summer, regional-scale wind events of up to 10 m/s are the dominant forcing for waves off the California coast, leading to relatively short-period waves (8-10 s) that come predominantly from the north-northwest. The wave climatology throughout the California Current region shows average significant wave heights exceeding 2 m during most of the year, which may have implications for the planning and retrieval methods of the Surface Water and Ocean Topography (SWOT) satellite mission.

  9. Eikonal Tomography of the Southern California Plate Boundary Region

    Science.gov (United States)

    Qiu, H.; Ben-Zion, Y.; Zigone, D.; Lin, F. C.

    2016-12-01

    We use eikonal tomography to derive directionally-dependent phase velocities of surface waves for the plate boundary region in southern CA sensitive to the approximate depth range 1-20 km. Seismic noise data recorded by 346 stations in the area provide a spatial coverage with 5-25 km typical station spacing and period range of 1-20 s. Noise cross-correlations are calculated for vertical component data recorded in year 2014. Rayleigh wave group and phase travel times between 2 and 13 sec period are derived for each station pair using frequency-time analysis. For each common station, all available phase travel time measurements with sufficient signal to noise ratio and envelope peak amplitude are used to construct a travel time map for a virtual source at the common station location. By solving the eikonal equation, both phase velocity and propagation direction are evaluated at each location for each virtual source. Isotropic phase velocities and 2-psi azimuthal anisotropy and their uncertainties are determined statistically using measurements from different virtual sources. Following the method of Barmin et al. (2001), group velocities are also inverted using all the group travel times that pass quality criteria. The obtained group and phase dispersions of Rayleigh waves are then inverted on a 6 x 6 km2 grid for local 1D piecewise shear wave velocity structures using the procedure of Herrmann (2013). The results agree well with previous observations of Zigone et al. (2015) in the overlapping area. Clear velocity contrasts and low velocity zones are seen for the San Andreas, San Jacinto, Elsinore and Garlock faults. We also find 2-psi azimuthal anisotropy with fast directions parallel to geometrically-simple fault sections. Details and updated results will be presented in the meeting.

  10. Development of State Interindustry Models for Rocky Mountain Region and California

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, Jayant A.; Kunin, Leonard

    1976-02-01

    Interindustry tables have been developed for the eight Rocky Mountain States and California. These tables are based on the 367-order 1967 national interindustry table. The national matrix was expanded to 404 sectors by disaggregating the seven minerals industries to 44 industries. The state tables can be used for energy and other resource analysis. Regional impacts of alternate development strategies can be evaluated with their use. A general computer program has been developed to facilitate construction of state interindustry tables.

  11. Modified Mercalli intensities for some recent California earthquakes and historic San Francisco Bay Region earthquakes

    Science.gov (United States)

    Bakun, William H.

    1998-01-01

    Modified Mercalli Intensity (MMI) data for recent California earthquakes were used by Bakun and Wentworth (1997) to develop a strategy for bounding the location and moment magnitude M of earthquakes from MMI observations only. Bakun (Bull. Seismol. Soc. Amer., submitted) used the Bakun and Wentworth (1997) strategy to analyze 19th century and early 20th century San Francisco Bay Region earthquakes. The MMI data and site corrections used in these studies are listed in this Open-file Report. 

  12. Results of the Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California.

    Science.gov (United States)

    Lee, Ya-Ting; Turcotte, Donald L; Holliday, James R; Sachs, Michael K; Rundle, John B; Chen, Chien-Chih; Tiampo, Kristy F

    2011-10-04

    The Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California was the first competitive evaluation of forecasts of future earthquake occurrence. Participants submitted expected probabilities of occurrence of M ≥ 4.95 earthquakes in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M ≥ 4.95 earthquakes occurred in the test region. These earthquakes occurred in 22 test cells. This seismic activity was dominated by earthquakes associated with the M = 7.2, April 4, 2010, El Mayor-Cucapah earthquake in northern Mexico. This earthquake occurred in the test region, and 16 of the other 30 earthquakes in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most "successful" in terms of the locations of future earthquakes. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts.

  13. Changing patterns in water toxicity associated with current use pesticides in three California agriculture regions.

    Science.gov (United States)

    Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Deng, Xin; Geraci, Jeff; Worcester, Karen; Tjeerdema, Ron S

    2018-03-01

    Regulation of agriculture irrigation water discharges in California, USA, is assessed and controlled by its 9 Regional Water Quality Control Boards under the jurisdiction of the California State Water Resources Control Board. Each Regional Water Board has developed programs to control pesticides in runoff as part of the waste discharge requirements implemented through each region's Irrigated Lands Regulatory Program. The present study assessed how pesticide use patterns differ in the Imperial (Imperial County) and the Salinas and Santa Maria (Monterey County) valleys, which host 3 of California's prime agriculture areas. Surface-water toxicity associated with current use pesticides was monitored at several sites in these areas in 2014 and 2015, and results were linked to changes in pesticide use patterns in these areas. Pesticide use patterns appeared to coincide with differences in the way agriculture programs were implemented by the 2 respective Regional Water Quality Control Boards, and these programs differed in the 2 Water Board Regions. Different pesticide use patterns affected the occurrence of pesticides in agriculture runoff, and this influenced toxicity test results. Greater detection frequency and higher concentrations of the organophosphate pesticide chlorpyrifos were detected in agriculture runoff in Imperial County compared to Monterey County, likely due to more rigorous monitoring requirements for growers using this pesticide in Monterey County. Monterey County agriculture runoff contained toxic concentrations of pyrethroid and neonicotinoid pesticides, which impacted amphipods (Hyalella azteca) and midge larvae (Chironomus dilutus) in toxicity tests. Study results illustrate how monitoring strategies need to evolve as regulatory actions affect change in pesticide use and demonstrate the importance of using toxicity test indicator species appropriate for the suite of contaminants in runoff in order to accurately assess environmental risk. Integr

  14. Los vidrios de baja emisividad

    Directory of Open Access Journals (Sweden)

    Olivares Santiago, Manuel

    1994-12-01

    Full Text Available The use of low-emittance coating (low-E glasses in Europe and the United States is not recent (they make use of them long since: 10-15years, nevertheless they are almost unknown in Spain, in all respects, in spite of being commercialized long since by different houses, specialists in these matters. We run into a lack of regulation about the qualities and stipulations these elements must comply with, since the regulations governing the thermal insulation of the buildings (CT-79 refers to the generic and peculiar qualities of the glazed openings, but these regulations do not approach the question of the real behaviour of the glazed openings with low-emittance glasses and other semi-transparent elements. The expenditure of energy and the lighting characteristics of the openings are not yet unforeseen, so far. These properties undergo a variation with regard to the base-glass or the support, due to the low-emittance coating. The article is organized in to three parts. The first part is the analysis of the functional characteristics and the lighting properties of the glasses from a general point of view. The second one explains what low-emittance glasses are, and the way of obtaining them (very briefly; according to the kind of process of obtaining the low-emission coating, the proceedings of low-emission glasses are gradually limited. Finally, the third part deals with the thermic characteristics of whole glazing, and specially with the glazed openings, from the point of view of a functional consistency for both glass and joinery.

    Aunque en Europa y EEUU el uso de los vidrios de baja emisividad no es reciente (se llevan utilizando unos 10-15 años, en España son prácticamente desconocidos desde el punto de vista teórico y práctico, a pesar de estar comercializándose desde hace varios años por las casas especializadas. Nos encontramos con un vacío normativo sobre las condiciones que han de cumplir, ya que la norma de

  15. GPS-seismograms reveal amplified shaking in California's San Joaquin Delta region

    Science.gov (United States)

    Johanson, I. A.

    2014-12-01

    The March 10, 2014, the Mw6.8 Ferndale earthquake occurred off the coast of Northern California, near the Mendocino Triple Junction. Aftershocks suggest a northeast striking fault plane for the strike-slip earthquake, oriented such that the California coast is roughly perpendicular to the rupture plane. Consequently, large amplitude Love waves were observed at seismic stations and continuous GPS stations throughout Northern California. While GPS is less sensitive then broadband instruments, in Northern California their station density is much higher, potentially providing valuable detail. A total of 269 GPS stations that have high-rate (1 sps) data available were used to generate GPS-seismograms. These include stations from the Bay Area Regional Deformation (BARD) network, the Plate Boundary Observatory (PBO, operated by UNAVCO), and the USGS, Menlo Park. The Track software package was used to generate relative displacements between pairs of stations, determined using Delaunay triangulation. This network-based approach allows for higher precision than absolute positioning, because common noise sources, in particular atmospheric noise, are cancelled out. A simple least-squares network adjustment with a stable centroid constraint is performed to transform the mesh of relative motions into absolute motions at individual GPS stations. This approach to generating GPS-seismograms is validated by the good agreement between time series records at 16 BARD stations that are co-located with broadband seismometers from the Berkeley Digital Seismic Network (BDSN). While the distribution of peak dynamic displacements is dominated in long periods by the radiation pattern, at shorter periods other patterns become visible. In particular, stations in the San Joaquin Delta (SJD) region show higher peak dynamic displacements than those in surrounding areas, as well as longer duration shaking. SJD stations also have higher dynamic displacements on the radial component than surrounding

  16. Assessing the geologic and climatic forcing of biodiversity and evolution surrounding the Gulf of California

    Science.gov (United States)

    Dolby, Greer; Bennett, Scott E. K.; Lira-Noriega, Andres; Wilder, Benjamin T.; Munguia-Vega, Adrian

    2015-01-01

    For almost a century the Baja California peninsula (Peninsula), Gulf of California (Gulf), and broader Sonoran Desert region (figure 1) have drawn geologists and biologists alike to study its unique physical and evolutionary processes (e.g., Wittich 1920; Darton 1921; Nelson 1921; Johnston 1924; Beal 1948; Durham and Allison 1960). The challenge remains to untangle the long, intricate, and at times enigmatic geological and climatological histories that have shaped the high levels of endemism and biodiversity observed in the region today (Van Devender 1990; Grismer 2000; Riddle et al. 2000).

  17. Local extirpations and regional declines of endemic upper beach invertebrates in southern California

    Science.gov (United States)

    Hubbard, D. M.; Dugan, J. E.; Schooler, N. K.; Viola, S. M.

    2014-10-01

    Along the world's highly valued and populous coastlines, the upper intertidal zones of sandy beach ecosystems and the biodiversity that these zones support are increasingly threatened by impacts of human activities, coastal development, erosion, and climate change. The upper zones of beaches typically support invertebrates with restricted distributions and dispersal, making them particularly vulnerable to habitat loss and fragmentation. We hypothesized that disproportionate loss or degradation of these zones in the last century has resulted in declines of upper shore macroinvertebrates in southern California. We identified a suite of potentially vulnerable endemic upper beach invertebrates with direct development, low dispersal and late reproduction. Based on the availability of printed sources and museum specimens, we investigated historical changes in distribution and abundance of two intertidal isopod species (Tylos punctatus, Alloniscus perconvexus) in southern California. Populations of these isopods have been extirpated at numerous historically occupied sites: T. punctatus from 16 sites (57% decrease), and A. perconvexus from 14 sites (64% decrease). During the same period, we found evidence of only five colonization events. In addition, the northern range limit of the southern species, T. punctatus, moved south by 31 km (8% of range on California mainland) since 1971. Abundances of T. punctatus have declined on the mainland coast; only three recently sampled populations had abundances >7000 individuals m-1. For A. perconvexus populations, abundances >100 individuals m-1 now appear to be limited to the northern part of the study area. Our results show that numerous local extirpations of isopod populations have resulted in regional declines and in greatly reduced population connectivity in several major littoral cells of southern California. Two of the six major littoral cells (Santa Barbara and Zuma) in the area currently support 74% of the remaining isopod

  18. Regional three-dimensional seismic velocity model of the crust and uppermost mantle of northern California

    Science.gov (United States)

    Thurber, C.; Zhang, H.; Brocher, T.; Langenheim, V.

    2009-01-01

    We present a three-dimensional (3D) tomographic model of the P wave velocity (Vp) structure of northern California. We employed a regional-scale double-difference tomography algorithm that incorporates a finite-difference travel time calculator and spatial smoothing constraints. Arrival times from earthquakes and travel times from controlled-source explosions, recorded at network and/or temporary stations, were inverted for Vp on a 3D grid with horizontal node spacing of 10 to 20 km and vertical node spacing of 3 to 8 km. Our model provides an unprecedented, comprehensive view of the regional-scale structure of northern California, putting many previously identified features into a broader regional context and improving the resolution of a number of them and revealing a number of new features, especially in the middle and lower crust, that have never before been reported. Examples of the former include the complex subducting Gorda slab, a steep, deeply penetrating fault beneath the Sacramento River Delta, crustal low-velocity zones beneath Geysers-Clear Lake and Long Valley, and the high-velocity ophiolite body underlying the Great Valley. Examples of the latter include mid-crustal low-velocity zones beneath Mount Shasta and north of Lake Tahoe. Copyright 2009 by the American Geophysical Union.

  19. A hydrogeologic map of the Death Valley region, Nevada, and California, developed using GIS techniques

    International Nuclear Information System (INIS)

    Faunt, C.C.; D'Agnese, F.A.; Turner, A.K.

    1997-01-01

    In support of Yucca Mountain site characterization studies, a hydrogeologic framework was developed, and a hydrogeologic map was constructed for the Death Valley region. The region, covering approximately 100,000 km 2 along the Nevada-California border near Las Vegas, is characterized by isolated mountain ranges juxtaposed against broad, alluvium-filled valleys. Geologic conditions are typical of the Basin and Range Province; a variety of sedimentary and igneous intrusive and extrusive rocks have been subjected to both compressional and extensional deformation. The regional ground-water flow system can best be described as a series of connected intermontane basins in which ground-water flow occurs in basin-fill deposits, carbonate rocks, clastic rocks, and volcanic rocks. Previous investigations have developed more site-specific hydrogeologic relationships; however, few have described all the lithologies within the Death Valley regional ground-water flow system. Information required to characterize the hydrogeologic units in the region was obtained from regional geologic maps and reports. Map data were digitized from regional geologic maps and combined into a composite map using a geographic information system. This map was simplified to show 10 laterally extensive hydrogeologic units with distinct hydrologic properties. The hydraulic conductivity values for the hydrogeologic units range over 15 orders of magnitude due to the variability in burial depth and degree of fracturing

  20. California coast sablefish - Reproductive Life History Analysis of Sablefish Populations off the Washington and California Coasts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sablefish (Anoplopoma fimbria) have a wide distribution along the Pacific coast, extending from Baja California to Alaska, the Bering Sea and through to the eastern...

  1. Summary appraisals of the Nation's ground-water resources; California region

    Science.gov (United States)

    Thomas, H.E.; Phoenix, D.A.

    1976-01-01

    Most people in the California Region live in a semiarid or arid climate, with precipitation less than the potential evapotranspiration- environments of perennial water deficiency. The deficiency becomes most onerous during the characteristically rainless summers and during recurrent droughts that may continue for 10--20 years. However, water from winter rain and snow can be stored for use during the dry summer months, and water stored during a wet climatic period can be used in a succeeding dry period; moreover, perennial deficiency can be overcome by bringing water from areas of perennial surplus. Ground-water reservoirs have especial significance in arid and semiarid regions as repositories where water is stored or can be stored with minimum loss by evaporation.

  2. High-resolution regional climate model evaluation using variable-resolution CESM over California

    Science.gov (United States)

    Huang, X.; Rhoades, A.; Ullrich, P. A.; Zarzycki, C. M.

    2015-12-01

    Understanding the effect of climate change at regional scales remains a topic of intensive research. Though computational constraints remain a problem, high horizontal resolution is needed to represent topographic forcing, which is a significant driver of local climate variability. Although regional climate models (RCMs) have traditionally been used at these scales, variable-resolution global climate models (VRGCMs) have recently arisen as an alternative for studying regional weather and climate allowing two-way interaction between these domains without the need for nudging. In this study, the recently developed variable-resolution option within the Community Earth System Model (CESM) is assessed for long-term regional climate modeling over California. Our variable-resolution simulations will focus on relatively high resolutions for climate assessment, namely 28km and 14km regional resolution, which are much more typical for dynamically downscaled studies. For comparison with the more widely used RCM method, the Weather Research and Forecasting (WRF) model will be used for simulations at 27km and 9km. All simulations use the AMIP (Atmospheric Model Intercomparison Project) protocols. The time period is from 1979-01-01 to 2005-12-31 (UTC), and year 1979 was discarded as spin up time. The mean climatology across California's diverse climate zones, including temperature and precipitation, is analyzed and contrasted with the Weather Research and Forcasting (WRF) model (as a traditional RCM), regional reanalysis, gridded observational datasets and uniform high-resolution CESM at 0.25 degree with the finite volume (FV) dynamical core. The results show that variable-resolution CESM is competitive in representing regional climatology on both annual and seasonal time scales. This assessment adds value to the use of VRGCMs for projecting climate change over the coming century and improve our understanding of both past and future regional climate related to fine

  3. Volatile organic compound measurements in the California/Mexico border region during SCOS97

    International Nuclear Information System (INIS)

    Zielinska, B.; Sagebiel, J.; Harshfield, G.; Pasek, R.

    2001-01-01

    Measurements of volatile organic compounds (VOC) were carried out in the California/Mexico border region during the Southern California Ozone Study in the summer of 1997 (SCOS97). Integrated 3-h samples were collected in Rosarito (south of Tijuana, Mexico) and in Mexicali during intensive operational periods (IOP), twice per IOP day. VOC were collected using stainless-steel 6-l canisters; carbonyl compounds were collected using 2,4-dinitrophenylhydrazine (DNPH) impregnated C18 SepPak cartridges. The canister samples were analyzed for speciated volatile hydrocarbons (C 2 -C 12 ), CO, CO 2 , CH 4 , methyl t-butyl ether (MTBE), and halogenated hydrocarbons. DNPH-impregnated cartridges were analyzed for 14 C 1 -C 7 carbonyl compounds. The concentrations of all species were higher at Mexicali than in Rosarito. A good correlation between total non-methane hydrocarbons (TNMHC), CO, and other pollutants associated with motor vehicle emissions observed for Mexicali indicates that the main source of TNMHC at this site is vehicular traffic

  4. Seismotectonic Implications Of Clustered Regional GPS Velocities In The San Francisco Bay Region, California

    Science.gov (United States)

    Graymer, R. W.; Simpson, R.

    2012-12-01

    We have used a hierarchical agglomerative clustering algorithm with Euclidean distance and centroid linkage, applied to continuous GPS observations for the Bay region available from the U.S. Geological Survey website. This analysis reveals 4 robust, spatially coherent clusters that coincide with 4 first-order structural blocks separated by 3 major fault systems: San Andreas (SA), Southern/Central Calaveras-Hayward-Rodgers Creek-Maacama (HAY), and Northern Calaveras-Concord-Green Valley-Berryessa-Bartlett Springs (NCAL). Because observations seaward of the San Gregorio (SG) fault are few in number, the cluster to the west of SA may actually contain 2 major structural blocks not adequately resolved: the Pacific plate to the west of the northern SA and a Peninsula block between the Peninsula SA and the SG fault. The average inter-block velocities are 11, 10, and 9 mm/yr across SA, HAY, and NCAL respectively. There appears to be a significant component of fault-normal compression across NCAL, whereas SA and HAY faults appear to be, on regional average, purely strike-slip. The velocities for the Sierra Nevada - Great Valley (SNGV) block to the west of NCAL are impressive in their similarity. The cluster of these velocities in a velocity plot forms a tighter grouping compared with the groupings for the other cluster blocks, suggesting a more rigid behavior for this block than the others. We note that for 4 clusters, none of the 3 cluster boundaries illuminate geologic structures other than north-northwest trending dominantly strike-slip faults, so plate motion is not accommodated by large-scale fault-parallel compression or extension in the region or by significant plastic deformation , at least over the time span of the GPS observations. Complexities of interseismic deformation of the upper crust do not allow simple application of inter-block velocities as long-term slip rates on bounding faults. However, 2D dislocation models using inter-block velocities and typical

  5. Precipitation in a warming world: Assessing projected hydro-climate changes in California and other Mediterranean climate regions.

    Science.gov (United States)

    Polade, Suraj D; Gershunov, Alexander; Cayan, Daniel R; Dettinger, Michael D; Pierce, David W

    2017-09-07

    In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, projections of changes in annual precipitation are inconsistent. Analysis of daily precipitation in 30 GCMs reveals patterns in projected hydrometeorology over each of the five MedClm regions globally and helps disentangle their causes. MedClim regions, except California, are expected to dry via decreased frequency of winter precipitation. Frequencies of extreme precipitation, however, are projected to increase over the two MedClim regions of the Northern Hemisphere where projected warming is strongest. The increase in heavy and extreme precipitation is particularly robust over California, where it is only partially offset by projected decreases in low-medium intensity precipitation. Over the Mediterranean Basin, however, losses from decreasing frequency of low-medium-intensity precipitation are projected to dominate gains from intensifying projected extreme precipitation. MedClim regions are projected to become more sub-tropical, i.e. made dryer via pole-ward expanding subtropical subsidence. California's more nuanced hydrological future reflects a precarious balance between the expanding subtropical high from the south and the south-eastward extending Aleutian low from the north-west. These dynamical mechanisms and thermodynamic moistening of the warming atmosphere result in increased horizontal water vapor transport, bolstering extreme precipitation events.

  6. Alpine Plant Monitoring for Global Climate Change; Analysis of the Four California GLORIA Target Regions

    Science.gov (United States)

    Dennis, A.; Westfall, R. D.; Millar, C. I.

    2007-12-01

    The Global Observation Research Initiative in Alpine Environments (GLORIA) is an international research project with the goal to assess climate-change impacts on vegetation in alpine environments worldwide. Standardized protocols direct selection of each node in the network, called a Target Region (TR), which consists of a set of four geographically proximal mountain summits at elevations extending from treeline to the nival zone. For each summit, GLORIA specifies a rigorous mapping and sampling design for data collection, with re-measurement intervals of five years. Whereas TRs have been installed in six continents, prior to 2004 none was completed in North America. In cooperation with the Consortium for Integrated Climate Research in Western Mountains (CIRMOUNT), California Native Plant Society, and the White Mountain Research Station, four TRs have been installed in California: two in the Sierra Nevada and two in the White Mountains. We present comparative results from analyses of baseline data across these four TRs. The number of species occurring in the northern Sierra (Tahoe) TR was 35 (16 not found in other TRs); in the central Sierra (Dunderberg) TR 65 species were found. In the White Mountains, 54 species were found on the granitic/volcanic soils TR and 46 (19 not found in other TRs) on the dolomitic soils TR. In all, we observed 83 species in the Sierra Nevada range TRs and 75 in the White Mountain TRs. Using a mixed model ANOVA of percent cover from summit-area-sections and quadrat data, we found primary differences to be among mountain ranges. Major soil differences (dolomite versus non-dolomite) also contribute to floristic differentiation. Aspect did not seem to contribute significantly to diversity either among or within target regions. Summit floras in each target region comprised groups of two distinct types of species: those with notably broad elevational ranges and those with narrow elevational ranges. The former we propose to be species that

  7. Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California

    Science.gov (United States)

    Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.

    2006-01-01

    This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a spatial database, (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map and liquefaction interpretation (part 3), and (4) a text introducing the report and describing the database (part 1). All parts of the report are digital; part 1 describes the database and digital files and how to obtain them by downloading across the internet. The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment. This new map provides a consistent detailed treatment of the central part of the 9-county region in which much of the mapping of Open-File Report 00-444 was either at smaller (less detailed) scale or represented only preliminary revision of earlier work. Like Open-File Report 00-444, the current mapping uses geomorphic expression, pedogenic soils, inferred depositional environments, and geologic age to define and distinguish the map units. Further scrutiny of the factors controlling liquefaction susceptibility has led to some changes relative to Open-File Report 00-444: particularly the reclassification of San Francisco Bay mud (Qhbm) to have only MODERATE susceptibility and the rating of artificial fills according to the Quaternary map units inferred to underlie them (other than dams - adf). The two colored

  8. LA COLECTIVIZACIÓN DE LA VIVIENDA EN EL SUBURBIO DE BAJA DENSIDAD. APROXIMACIONES A PROPÓSITO DEL PLAN TERRITORIAL METROPOLITANO DE BARCELONA / The collectivization of housing in the low density suburbs. Approaches regarding the regional metropolitan plan

    Directory of Open Access Journals (Sweden)

    Roger Joan Sauquet Llonch

    2011-11-01

    Full Text Available RESUMEN El crecimiento de los suburbios de baja densidad alrededor de las ciudades españolas durante la anterior década plantea un grave problema ambiental. No sólo es su crecimiento en extensión y la consiguiente reducción de áreas agrícolas o forestales lo que es preocupante, sino también la dependencia de sus habitantes del automóvil y la inviabilidad del transporte público. Para minimizar desplazamientos, el Plan Territorial Metropolitano de Barcelona propone inserir focos de densidad en el interior de estas áreas. Sin embargo, el Plan carece de propuestas arquitectónicas concretas; simplemente apunta hacia una dirección. Más allá del criterio ambiental, este artículo utiliza esta propuesta del Plan para reflexionar sobre qué sensibilidades debería respetar la vivienda colectiva suburbial, entendiendo que es desde el habitante y su modo de vivir como debemos empezar a abordar la “colectivización” del suburbio. La aproximación se efectúa mediante la revisión de ejemplos de edificios residenciales surgidos en distintos momentos arquitectónicos del siglo veinte, que resuelven de una u otra forma la relación de la vivienda con un espacio exterior privado, una relación de especial trascendencia para cualquier habitante suburbial. Estos modelos se agrupan en tres conjuntos: las viviendas obreras del primer tercio de siglo, los edificios escalonados generados durante el Movimiento Moderno y los diseños residenciales “inacabados” del tercer mundo. Después de observar los recursos utilizados en estos modelos concluimos con una serie de consideraciones inspiradas, a la vez, en otros ejemplos residenciales más recientes y orientadas a alumbrar el dilema entre densidad y suburbio en la actualidad. SUMMARY The growth of low-density suburbs around Spanish cities during the past decade poses a serious environmental problem. Not only is it the growth in size and the consequent reduction in agricultural or forest areas

  9. Correspondence of biological condition models of California streams at statewide and regional scales

    Science.gov (United States)

    May, Jason T.; Brown, Larry R.; Rehn, Andrew C.; Waite, Ian R.; Ode, Peter R; Mazor, Raphael D; Schiff, Kenneth C

    2015-01-01

    taxonomic completeness is imperative for sound management. Our results suggest that invertebrate taxonomic completeness is affected by human disturbance at the statewide and regional levels, with some differences among regions in the importance of natural gradients and types of human disturbance. The construction and application of models similar to the ones presented here could be useful in the planning and prioritization of actions for protection and conservation of biodiversity in California streams.

  10. Effects of Climate on the Zooplankton of the California Current

    Science.gov (United States)

    Lavaniegos, B. E.

    2007-05-01

    Almost six decades of sampling of the California Current system, carried out by the CalCOFI program (California Cooperative Fisheries Investigation) complemented by a decade of observations from the IMECOCAL program (Investigaciones Mexicanas de la Corriente de California), have revealed changing patterns in zooplankton abundances, species composition, and distributions over interannual through multidecadal time scales. Interannual changes associated with ENSO variability are manifested as strong but transitory perturbations in the mean annual cycle in seasonal abundances (and distributions) of particular species. An investigation of longer- term change, limited to the region off southern California, shows a persistent decline in zooplankton volumes (a proxy for overall biomass of macrozooplankton) between 1977 and 1998 that is considered to be a response to the well documented shift in basin-scale climate forcing that occurred in 1976-77. Further examination of this decline in zooplankton volumes indicates that it was due principally to the disappearance of several salp species after 1977. Other species and functional groups did not decline after the change in climate regime, while some species have followed persistent secular trends that appear to be associated more with the phenomenon of long-term global warming. Differences in the regional responses to climate change throughout the California Current system have also been observed recently in the spatial distribution of zooplankton biomass and changes in latitudinal ranges of certain species. For example, zooplankton biomass in the Baja California region show typical values for the 1997-98 El Niño that were followed by a decrease during the sharp transition to the cool La Niña conditions in 1999. This contrasts with the nearby region off southern California that was characterized by reduced biomass during the El Niño period and the subsequent recovery during the La Niña. Another regional contrast in

  11. A Seasonal Perspective on Regional Air Quality in CentralCalifornia - Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Harley, Robert A.; Brown, Nancy J.; Tonse, Shaheen R.; Jin, Ling

    2006-12-01

    Central California spans a wide variety of urban, agricultural, and natural terrain, including the San Francisco Bay area, the Central Valley, and the Sierra Nevada Mountains. Population within this region is growing rapidly, and there are persistent, serious air pollution problems including fine particulate matter (PM{sub 2.5}) and ozone. Summertime photochemical air pollution is the focus of the present study, which represents a first phase in the development and application of a modeling capability to assess formation and transport of ozone and its precursors within Central California over an entire summer season. This contrasts with past studies that have examined pollutant dynamics for a few selected high-ozone episodes each lasting 3-5 days. The Community Multiscale Air Quality model (CMAQ) has been applied to predict air pollutant formation and transport in Central California for a 15-day period beginning on July 24, 2000. This period includes a 5-day intensive operating period (July 29 to August 2) from the Central California Ozone Study (CCOS). Day-specific meteorological conditions were modeled by research collaborators at NOAA using a mesoscale meteorological model (MM5). Pollutant emissions within the study domain were based on CARB emission inventory estimates, with additional efforts conducted as part of this research to capture relevant emissions variability including (1) temperature and sunlight-driven changes in biogenic VOC, (2) weekday/weekend and diurnal differences in light-duty (LD) and heavy-duty (HD) motor vehicle emissions, (3) effects of day-specific meteorological conditions on plume rise from point sources such as power plants. We also studied the effects of using cleaner pollutant inflow boundary conditions, lower than indicated during CCOS aircraft flights over the Pacific Ocean, but supported by other surface, ship-based, balloon and aircraft sampling studies along the west coast. Model predictions were compared with measured

  12. Standards establishment within Baja California’s horticultural sector

    Directory of Open Access Journals (Sweden)

    Belem Avendaño Ruiz

    2010-01-01

    Full Text Available The Baja California produce industry is notice by its strong export orientation production. Never less, in the past few years some products have been associated to food safety outbreaks in the United States, its main market, affecting its competitiveness and market share, driven produce growers to the adoption of standards as a mean to stay in the international market. The paper focus in the role of adoption of International standards in the firms as part of a competitive strategy that implies a technological change in order to comply with the certification requirements. A descriptive statistical analysis is conducted as well as a discriminate analysis in order to explain the factors that are involved in the firms that present technical innovation (adoption of standards to achieve competitiveness and those that don’t improve their productive process.

  13. Regional Attenuation in Northern California: A Comparison of Five 1-D Q Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ford, S R; Dreger, D S; Mayeda, K; Walter, W R; Malagnini, L; Phillips, W S

    2007-08-03

    The determination of regional attenuation Q{sup -1} can depend upon the analysis method employed. The discrepancies between methods are due to differing parameterizations (e.g., geometrical spreading rates), employed datasets (e.g., choice of path lengths and sources), and the methodologies themselves (e.g., measurement in the frequency or time domain). Here we apply five different attenuation methodologies to a Northern California dataset. The methods are: (1) coda normalization (CN), (2) two-station (TS), (3) reverse two-station (RTS), (4) source-pair/receiver-pair (SPRP), and (5) coda-source normalization (CS). The methods are used to measure Q of the regional phase, Lg (Q{sub Lg}), and its power-law dependence on frequency of the form Q{sub 0}f{sup {eta}} with controlled parameterization in the well-studied region of Northern California using a high-quality dataset from the Berkeley Digital Seismic Network. We investigate the difference in power-law Q calculated among the methods by focusing on the San Francisco Bay Area, where knowledge of attenuation is an important part of seismic hazard mitigation. This approximately homogeneous subset of our data lies in a small region along the Franciscan block. All methods return similar power-law parameters, though the range of the joint 95% confidence regions is large (Q{sub 0} = 85 {+-} 40; {eta} = 0.65 {+-} 0.35). The RTS and TS methods differ the most from the other methods and from each other. This may be due to the removal of the site term in the RTS method, which is shown to be significant in the San Francisco Bay Area. In order to completely understand the range of power-law Q in a region, it is advisable to use several methods to calculate the model. We also test the sensitivity of each method to changes in geometrical spreading, Lg frequency bandwidth, the distance range of data, and the Lg measurement window. For a given method, there are significant differences in the power-law parameters, Q{sub 0} and {eta

  14. Geology and uranium favorability of the Sonora Pass region, Alpine and Tuolumne Counties, California

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, J.S.; Short, W.O.

    1981-06-01

    Uranium mineralization at the Juniper Mine is restricted to host rocks of the Relief Peak Formation and is most common in coarse-grained lithic sandstone, conglomerate, and lithic wacke. The richest beds contain as much as 0.5% U/sub 3/O/sub 8/. Uranium is present as coffinite, uraninite, and unidentified minerals. Thorium/uranium ratios are generally low and erratic. Equivalent uranium determinations are low in comparison with chemical uranium values, indicating that uranium mineralization of the Juniper Mine is geologically young. Core drilling at 16 localities shows that widely separated exposures of the Relief Peak Formation have very similar lithology, geochemistry, and stratigraphy. Some sections are similar to the Juniper Mine section. Core from the bottom of drill hole SP-1 contains 83 ppM uranium, the greatest known concentration outside the mine area. Significant uranium deposits may be concealed beneath the thick Tertiary volcanic cover of the region. The quartz latitic Eureka Valley Tuff is fairly widespread in east-central California and western Nevada. It contains 12 to 14 ppM uranium and stratigraphically overlies the Relief Peak Formation. It is permeable and contains abundant alkali metals and volcanic glass. Because of its petrology, geochemistry, and position, this formation is the most likely source for uranium mineralization of the Sonora Pass region. It should be examined as a potential source rock in other areas with special regard to its relationship to carbonaceous sedimentary formations. The uraniferous granite pegmatitite dike that crops out in the Niagara Creek area appears too small to be a significant source rock. The most favorable rocks in the Sonora Pass region occur near the Juniper Mine and west of it, in the Dardanelles, the Whittakers Dardanelles, and the area of the Big Meadow Quadrangle. Potential uranium host rocks crop out in areas along the crest of the Sierra Nevada from Lake Tahoe to Yosemite.

  15. Geology and uranium favorability of the Sonora Pass region, Alpine and Tuolumne Counties, California

    International Nuclear Information System (INIS)

    Rapp, J.S.; Short, W.O.

    1981-06-01

    Uranium mineralization at the Juniper Mine is restricted to host rocks of the Relief Peak Formation and is most common in coarse-grained lithic sandstone, conglomerate, and lithic wacke. The richest beds contain as much as 0.5% U 3 O 8 . Uranium is present as coffinite, uraninite, and unidentified minerals. Thorium/uranium ratios are generally low and erratic. Equivalent uranium determinations are low in comparison with chemical uranium values, indicating that uranium mineralization of the Juniper Mine is geologically young. Core drilling at 16 localities shows that widely separated exposures of the Relief Peak Formation have very similar lithology, geochemistry, and stratigraphy. Some sections are similar to the Juniper Mine section. Core from the bottom of drill hole SP-1 contains 83 ppM uranium, the greatest known concentration outside the mine area. Significant uranium deposits may be concealed beneath the thick Tertiary volcanic cover of the region. The quartz latitic Eureka Valley Tuff is fairly widespread in east-central California and western Nevada. It contains 12 to 14 ppM uranium and stratigraphically overlies the Relief Peak Formation. It is permeable and contains abundant alkali metals and volcanic glass. Because of its petrology, geochemistry, and position, this formation is the most likely source for uranium mineralization of the Sonora Pass region. It should be examined as a potential source rock in other areas with special regard to its relationship to carbonaceous sedimentary formations. The uraniferous granite pegmatitite dike that crops out in the Niagara Creek area appears too small to be a significant source rock. The most favorable rocks in the Sonora Pass region occur near the Juniper Mine and west of it, in the Dardanelles, the Whittakers Dardanelles, and the area of the Big Meadow Quadrangle. Potential uranium host rocks crop out in areas along the crest of the Sierra Nevada from Lake Tahoe to Yosemite

  16. Salud reproductiva entre migrantes de Tijuana, Baja California

    Directory of Open Access Journals (Sweden)

    Germán Vega Briones

    2008-01-01

    Full Text Available La idea central de este artículo es mostrar el nivel de conocimientos, los mitos y actitudes de mig rantes que laboran o han laborado en Estados Unidos y analizar cómo ha impactado su t rabajo en la Unión Americana en términos de su salud reproductiva y sexual.

  17. Coastal currents and mass transport of surface sediments over the shelf regions of Monterey Bay, California

    Science.gov (United States)

    Wolf, S.C.

    1970-01-01

    In Monterey Bay, the highest concentrations of medium and fine sands occur nearshore between ten and thirty fathoms. Silt and clay accumulate in greater depths. Contours of median diameter roughly parallel the isobaths. Fine-grained materials are supplied to the bay region from erosion of cliffs which partly surround Monterey Bay, from sediment laden river discharge, and from continual reworking of widespread Pleistocene and Recent sea floor sediments. These sediments in turn are picked up by coastal currents and distributed over the shelf regions by present day current regimes. Studies of bottom currents over the shelf regions and in Monterey Canyon have revealed patterns which vary with seasonal changes. Current patterns during August and September exhibit remarkable symmetry about the axis of Monterey Submarine Canyon. Central Shelf currents north and south of Monterey Canyon flowed northwest at an average rate of 0.2 knots and south at 0.3 knots respectively. On the North Shelf between January and March currents flowed east to southeast at 0.3-0.5 knots with mirror image patterns above the South Shelf during the same period. Irregular current flow in the canyon indicates a complex current structure with frequent shifts in counterclockwise and clockwise direction over very short periods of time. Bottom topography of the canyon complex often causes localization of canyon currents. One particular observation at a depth of 51 fathoms indicated up-canyon flow at a rate of 0.2 knots. Most of the observed currents are related to seasonal variations, upwelling, ocean swell patterns, and to changes in the California and Davidson currents. Changes in current regimes are reflected in the patterns of sediment distribution and transport. Sediment transport is chiefly parallel to the isobaths, particularly on the North and South Shelf regions. Complex dispersal patterns are observed near Monterey Canyon and Moss Landing Harbor jetties. Longshore currents move sediments

  18. Evaluating Form and Function of Regional Partnerships: Applying Social Network Analysis to the "Network for a Healthy California", 2001-2007

    Science.gov (United States)

    Gregson, Jennifer; Sowa, Marcy; Flynn, Heather Kohler

    2011-01-01

    Objective: To evaluate the partnership structure of the "Network for a Healthy California" ("Network"), a social marketing program, from 2001-2007, to determine if California's program was able to establish and maintain partnerships that (1) provided access to a local audience, (2) facilitated regional collaboration, (3)…

  19. Evaluation and Analysis of Regional Best Management Practices in San Diego, California (USA)

    Science.gov (United States)

    Flint, K.; Kinoshita, A. M.

    2017-12-01

    In urban areas, surface water quality is often impaired due to pollutants transported by stormwater runoff. To maintain and improve surface water quality, the United States Clean Water Act (CWA) requires an evaluation of available water quality information to develop a list of impaired water bodies and establish contaminant restrictions. Structural Best Management Practices (BMPs) are designed to reduce runoff volume and/or pollutant concentrations to comply with CWA requirements. Local level policy makers and managers require an improved understanding of the costs and benefits associated with BMP installation, performance, and maintenance. The International Stormwater BMP Database (Database) is an online platform for submittal of information about existing BMPs, such as cost, design details, and statistical analysis of influent and effluent pollutant concentrations. While the Database provides an aggregation of data which supports analysis of overall BMP performance at international and national scales, the sparse spatial distribution of the data is not suitable for regional and local analysis. This research conducts an extensive review of local inventory and spatial analysis of existing permanent BMPs throughout the San Diego River watershed in California, USA. Information collected from cities within the San Diego River watershed will include BMP types, locations, dates of installation, costs, expected removal efficiencies, monitoring data, and records of maintenance. Aggregating and mapping this information will facilitate BMP evaluation. Specifically, the identification of spatial trends, inconsistencies in BMP performances, and gaps in current records. Regression analysis will provide insight into the nature and significance of correlations between BMP performance and physical characteristics such as land use, soil type, and proximity to impaired waters. This analysis will also result in a metric of relative BMP performance and will provide a basis for future

  20. Full-Wave Ambient Noise Tomography of the Long Valley Volcanic Region (California)

    Science.gov (United States)

    Flinders, A. F.; Shelly, D. R.; Dawson, P. B.; Hill, D. P.; Shen, Y.

    2017-12-01

    In the late 1970s, and throughout the 1990s, Long Valley Caldera (California) experienced intense periods of unrest characterized by uplift of the resurgent dome, earthquake swarms, and CO2 emissions around Mammoth Mountain. While modeling of the uplift and gravity changes support the possibility of new magmatic intrusions beneath the caldera, geologic interpretations conclude that the magmatic system underlying the caldera is moribund. Geophysical studies yield diverse versions of a sizable but poorly resolved low-velocity zone at depth (> 6km), yet whether this zone is indicative of a significant volume of crystal mush, smaller isolated pockets of partial melt, or magmatic fluids, is inconclusive. The nature of this low-velocity zone, and the state of volcano's magmatic system, carry important implications for the significance of resurgent-dome inflation and the nature of associated hazards. To better characterize this low-velocity zone we present preliminary results from a 3D full-waveform ambient-noise seismic tomography model derived from the past 25 years of vertical component broadband and short-period seismic data. This new study uses fully numerical solutions of the wave equation to account for the complex wave propagation in a heterogeneous, 3D earth model, including wave interaction with topography. The method ensures that wave propagation is modeled accurately in 3D, enabling the full use of seismic records. By using empirical Green's functions, derived from ambient noise and modeled as Rayleigh surface waves, we are able to extend model resolution to depths beyond the limits of previous local earthquake studies. The model encompasses not only the Long Valley Caldera, but the entire Long Valley Volcanic Region, including Mammoth Mountain and the Mono Crater/Inyo Domes volcanic chain.

  1. Present, future, and novel bioclimates of the San Francisco, California region

    Science.gov (United States)

    Torregrosa, Alicia; Taylor, Maxwell D.; Flint, Lorraine E.; Flint, Alan L.

    2013-01-01

    Bioclimates are syntheses of climatic variables into biologically relevant categories that facilitate comparative studies of biotic responses to climate conditions. Isobioclimates, unique combinations of bioclimatic indices (continentality, ombrotype, and thermotype), were constructed for northern California coastal ranges based on the Rivas-Martinez worldwide bioclimatic classification system for the end of the 20th century climatology (1971–2000) and end of the 21st century climatology (2070–2099) using two models, Geophysical Fluid Dynamics Laboratory (GFDL) model and the Parallel Climate Model (PCM), under the medium-high A2 emission scenario. The digitally mapped results were used to 1) assess the relative redistribution of isobioclimates and their magnitude of change, 2) quantify the loss of isobioclimates into the future, 3) identify and locate novel isobioclimates projected to appear, and 4) explore compositional change in vegetation types among analog isobioclimate patches. This study used downscaled climate variables to map the isobioclimates at a fine spatial resolution −270 m grid cells. Common to both models of future climate was a large change in thermotype. Changes in ombrotype differed among the two models. The end of 20th century climatology has 83 isobioclimates covering the 63,000 km2 study area. In both future projections 51 of those isobioclimates disappear over 40,000 km2. The ordination of vegetation-bioclimate relationships shows very strong correlation of Rivas-Martinez indices with vegetation distribution and composition. Comparisons of vegetation composition among analog patches suggest that vegetation change will be a local rearrangement of species already in place rather than one requiring long distance dispersal. The digitally mapped results facilitate comparison with other Mediterranean regions. Major remaining challenges include predicting vegetation composition of novel isobioclimates and developing metrics to compare

  2. Present, future, and novel bioclimates of the San Francisco, California region.

    Directory of Open Access Journals (Sweden)

    Alicia Torregrosa

    Full Text Available Bioclimates are syntheses of climatic variables into biologically relevant categories that facilitate comparative studies of biotic responses to climate conditions. Isobioclimates, unique combinations of bioclimatic indices (continentality, ombrotype, and thermotype, were constructed for northern California coastal ranges based on the Rivas-Martinez worldwide bioclimatic classification system for the end of the 20(th century climatology (1971-2000 and end of the 21(st century climatology (2070-2099 using two models, Geophysical Fluid Dynamics Laboratory (GFDL model and the Parallel Climate Model (PCM, under the medium-high A2 emission scenario. The digitally mapped results were used to 1 assess the relative redistribution of isobioclimates and their magnitude of change, 2 quantify the loss of isobioclimates into the future, 3 identify and locate novel isobioclimates projected to appear, and 4 explore compositional change in vegetation types among analog isobioclimate patches. This study used downscaled climate variables to map the isobioclimates at a fine spatial resolution -270 m grid cells. Common to both models of future climate was a large change in thermotype. Changes in ombrotype differed among the two models. The end of 20(th century climatology has 83 isobioclimates covering the 63,000 km(2 study area. In both future projections 51 of those isobioclimates disappear over 40,000 km(2. The ordination of vegetation-bioclimate relationships shows very strong correlation of Rivas-Martinez indices with vegetation distribution and composition. Comparisons of vegetation composition among analog patches suggest that vegetation change will be a local rearrangement of species already in place rather than one requiring long distance dispersal. The digitally mapped results facilitate comparison with other Mediterranean regions. Major remaining challenges include predicting vegetation composition of novel isobioclimates and developing metrics to

  3. Field Trip Guide to Serpentinite, Silica-Carbonate Alteration, and Related Hydrothermal Activity in the Clear Lake Region, California

    Energy Technology Data Exchange (ETDEWEB)

    Fraser Goff; George Guthrie

    1999-06-01

    This guide is designed to familiarize scientists with the geology, structure, alteration, and fluids typical of California serpentinites for purposes of carbon dioxide sequestration (Lackner et al., 1995). Goff et al. (1997) and Goff and Lackner (1998) describe the geology and geochemistry of some of the serpentinites from this area. Mechanisms of silica-carbonate alteration were outlined by Barnes et al. (1973). Donnelly-Nolan et al. (1993) most recently reviewed relations between regional hydrothermal alteration and Quarternary volcanic activity. Stanley et al. (1998) summarized geophysical characteristics of the region.

  4. Preliminaries to a feasibility analysis of the Maglev proposal of the Southern California Association of Governments for the region : a seed grant study report

    Science.gov (United States)

    2009-08-30

    This is a seed grant study to perform a preliminary investigation of the system components and : generalized costs of the magnetic levitation type of high speed rail system that is proposed for the : Southern California Region, TGVbased high speed...

  5. The California Border Health Collaborative: A Strategy for Leading the Border to Better Health

    Directory of Open Access Journals (Sweden)

    Charles Edwards Matthews III

    2015-05-01

    Full Text Available There are hundreds of departments and organizations working on border health issues in the California/Baja California border region trying to protect and improve health without a collaborative structure that integrates jurisdictions and organizations. As a result, there is a need to effectively improve the health in the border region by coordinating these organizations to work together and benefit from each other’s best practices. The newly developed California Border Health Collaborative (CBHC can provide the leadership and collaborative culture to positively improve the health of the border region. This article aims to describe the development process of this collaborative to include key ingredients to success, the roles of mulit-level jurisdictions, and policy implications.This article describes the methods used to develop key aspects of collaborative leadership, strategic alignment and a common vision toward the building of this collective impact approach to border health. In addition, we describe the role of key local County (County of San Diego Live Well San Diego initiative, State, (California Department of Public Health- Office of Binational Border Health, Federal (US-Mexico Border Health Commission’s Leaders across Borders, Academia (e.g., University of California San Diego and San Diego State University and non-profit entities (e.g., Project Concern International, San Ysidro Health Center in forming the BHCC. Evaluating the consortium development process included a literature review of similar processes, a review of internal documents and an analysis of developmental events. To this point the CBHC has built a strong, cohesive collaborative on the U.S. side of the border. It is sharing and leveraging local expertise to address many border health issues. Even more importantly, the BHCC has reached a key stage in which it can effectively engage its Baja California, Mexico counterparts in a manner that will prove extremely powerful

  6. Urban and community forests of the Pacific region: California, Oregon, Washington

    Science.gov (United States)

    David J. Nowak; Eric J. Greenfield

    2010-01-01

    This report details how land cover and urbanization vary within the states of California, Oregon, and Washington by community (incorporated and census designated places), county subdivision, and county. Specifically this report provides critical urban and community forestry information for each state including human population characteristics and trends, changes in...

  7. The California Alliance for Sustainability: A Collaborative Pilot Project to Build Regional Advocacy and Leadership for Sustainability Education

    Science.gov (United States)

    Metzger, E. P.; Smith, G.; Cordero, E. C.; Santone, S.

    2012-12-01

    For Education for Sustainability (Efs) to have the presence in the K-12 curriculum that it arguably should, considerable obstacles must be overcome. Barriers include the role of high-stakes testing in marginalizing science and social studies and the lack of environmental and sustainability content in teacher education programs. The California Alliance for Sustainability (CASE), a collaborative 18-month project funded by the Clarence E. Heller Charitable Foundation, unites San José State University (SJSU) and Creative Change Educational Solutions (CCES) (http://www.creativechange.net/) to investigate and address potential barriers to Efs in San Francisco Bay area schools and regional teacher education programs and to document best practices for integrating sustainability into teachers' existing standards-based teaching. The overarching goal of the CASE project is to create a regional infrastructure of K-12 teachers and pre-service teacher educators who use EfS as a context for educational innovation and transformation, thus supplying a focused first step for investigating how Efs can be more broadly implemented in California's classrooms. This presentation will showcase the efforts of a pilot group of classroom teachers and teacher educators to bring EfS to their teaching. In summer 2012, the CASE Project provided 16 in-service teachers and 5 pre-service teacher education faculty from SJSU and California State University East Bay with a three-day professional development workshop. Practicing teachers and teacher educators experienced joint instruction in the content and pedagogy of sustainability though investigation of topics (e.g., Sustainable Communities, Ecological Footprint Analysis, Climate Change, Resource Use, Food Systems and Life Cycle Analysis) that offer broad connections to California standards in science and other disciplines. Sustainability concepts were also discussed as an engaging context for addressing the emerging Common Core and Next Generation

  8. Regional Systems Development for Geothermal Energy Resources Pacific Region (California and Hawaii). Task 3: water resources evaluation. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Sakaguchi, J.L.

    1979-03-19

    The fundamental objective of the water resources analysis was to assess the availability of surface and ground water for potential use as power plant make-up water in the major geothermal areas of California. The analysis was concentrated on identifying the major sources of surface and ground water, potential limitations on the usage of this water, and the resulting constraints on potentially developable electrical power in each geothermal resource area. Analyses were completed for 11 major geothermal areas in California: four in the Imperial Valley, Coso, Mono-Long Valley, Geysers-Calistoga, Surprise Valley, Glass Mountain, Wendel Amedee, and Lassen. One area in Hawaii, the Puna district, was also included in the analysis. The water requirements for representative types of energy conversion processes were developed using a case study approach. Cooling water requirements for each type of energy conversion process were estimated based upon a specific existing or proposed type of geothermal power plant. The make-up water requirements for each type of conversion process at each resource location were then estimated as a basis for analyzing any constraints on the megawatts which potentially could be developed.

  9. The California Valley grassland

    Science.gov (United States)

    Keeley, J.E.; Schoenherr, Allan A.

    1990-01-01

    Grasslands are distributed throughout California from Oregon to Baja California Norte and from the coast to the desert (Brown 1982) (Figure 1). This review will focus on the dominant formation in cismontane California, a community referred to as Valley Grassland (Munz 1959). Today, Valley Grassland is dominated by non-native annual grasses in genera such as Avena (wild oat), Bromus (brome grass), and Hordeum (barley), and is often referred to as the California annual grassland. On localized sites, native perennial bunchgrasses such as Stipa pultra (purple needle grass) may dominate and such sites are interpreted to be remnants of the pristine valley grassland. In northwestern California a floristically distinct formation of the Valley Grassland, known as Coast Prairie (Munz 1959) or Northern Coastal Grassland (Holland and Keil 1989) is recognized. The dominant grasses include many native perennial bunchgrasses in genera such as Agrostis, Calamagrostis, Danthonia, Deschampsia, Festuca, Koeleria and Poa (Heady et al. 1977). Non-native annuals do not dominate, but on some sites non-native perennials like Anthoxanthum odoratum may colonize the native grassland (Foin and Hektner 1986). Elevationally, California's grasslands extend from sea level to at leas 1500 m. The upper boundary is vague because montane grassland formations are commonly referred to as meadows; a community which Munz (1959) does not recognize. Holland and Keil (1989) describe the montane meadow as an azonal community; that is, a community restricted not so much to a particular climatic zone but rather controlled by substrate characteristics. They consider poor soil-drainage an over-riding factor in the development of montane meadows and, in contrast to grasslands, meadows often remain green through the summer drought. Floristically, meadows are composed of graminoids; Cyperaceae, Juncaceae, and rhizomatous grasses such as Agropyron (wheat grass). Some bunchgrasses, such as Muhlenbergia rigens, are

  10. Current depression among women in California according to residence in the California-Mexico border region Depresión actual en las mujeres en California según el lugar de residencia en la región fronteriza entre California y México

    Directory of Open Access Journals (Sweden)

    Suzanne Ryan-Ibarra

    2012-05-01

    Full Text Available OBJECTIVE: To estimate the prevalence of current depression; examine the relationship between current depression and immigration, health status, health care access, and health behaviors; and assess differences by California-Mexico border region (Imperial and San Diego Counties among women in California. METHODS: Using a cross-sectional, representative sample of adult women from the California Women's Health Survey (n = 13 454, a statewide telephone survey, prevalence of current depression and predictors of depression were examined in California and according to border region residence. Depression was assessed with the eight-item Patient Health Questionnaire. RESULTS: The prevalence of current depression for women in California was 12.0%. It was similar in the border (13.0% and the nonborder (11.9% regions. Odds of current depression in women were lower among recent immigrants (OBJETIVO: Calcular la prevalencia de la depresión actual; examinar la relación entre la depresión actual y la inmigración, el estado de salud, el acceso a la atención de la salud y las conductas relacionadas con la salud; y evaluar las diferencias en la región fronteriza entre California (condados Imperial y San Diego y México en las mujeres. MÉTODOS: Se empleó una muestra transversal y representativa de mujeres adultas de la Encuesta de Salud de la Mujer de California (n = 13 454, una encuesta telefónica estatal, para examinar la prevalencia de depresión actual y los factores predictivos de depresión tanto en California como según el lugar de residencia en la región fronteriza. La depresión se evaluó mediante el Cuestionario de Salud del Paciente-8. RESULTADOS: La prevalencia de depresión actual en las mujeres en California fue 12,0%, y fue semejante en las regiones fronteriza (13,0% y no fronteriza (11,9% del estado. Las probabilidades de presentar depresión actual fueron menores en las mujeres que habían inmigrado recientemente (< 5 años o de 5 a

  11. WATER TEMPERATURE, SALINITY, and HYDROSTATIC PRESSURE collected from R/V Point Sur in Entrance to the Gulf of California from 2013-04-19 to 2013-05-02 (NCEI Accession 0131072)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrographic data were collected in Pescadero Basin (at the entrance to the Gulf of California) and subsequently along the West Coast of Baja California and Southern...

  12. Washington coast sablefish - Reproductive Life History Analysis of Sablefish Populations off the Washington and California Coasts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sablefish (Anoplopoma fimbria) have a wide distribution along the Pacific coast, extending from Baja California to Alaska, the Bering Sea and through to the eastern...

  13. Evolution of regional stress state based on faulting and folding near the pit river, Shasta county, California

    Science.gov (United States)

    Austin, Lauren Jean

    We investigate the evolution of the regional stress state near the Pit River, northern California, in order to understand the faulting style in a tectonic transition zone and to inform the hazard analysis of Fault 3432 near the Pit 3 Dam. By analyzing faults and folds preserved in and adjacent to a diatomite mine north of the Pit River, we have determined principal stress directions preserved during the past million years. We find that the stress state has evolved from predominantly normal to strike slip and most recently to reverse, which is consistent with regional structures such as the extensional Hat Creek Fault to the south and the compressional folding of Mushroom Rock to the north. South of the Pit River, we still observe normal and strike slip faults, suggesting that changes in stress state are moving from north to south through time.

  14. Education in a Global Age: An Inter-California Strategy for the Tijuana-San Diego Region

    Directory of Open Access Journals (Sweden)

    Olga A. Vásquez

    2002-01-01

    Full Text Available Este artículo presenta un bosquejo para una estrategia Inter-California que enlazaría las áreas de San Diego y Tijuana como una sola fuerza regional. Esto intenta conceptualizar dos distintas y frecuentemente contradictorias áreas como una sola, haciendo una aproximación a grosso modo de las desiguales condiciones económicas y educativas en ambos lados de la frontera. Se discute la colaboración binacional en el pasado en educación, y se plantean las posibilidades para el futuro de dicha colaboración, ofreciendo recomendaciones y predicciones de las metas que podrían alcanzarse. Llamando a la región Inter-California, el artículotambién argumenta por una identidad global, y específicamente, por una educación que es relevante para la nueva economía, asi como los avances científicos y tecnológicos que están iluminando cada vez más una nueva sociedad global.

  15. Radiated Seismic Energy of Earthquakes in the South-Central Region of the Gulf of California, Mexico

    Science.gov (United States)

    Castro, Raúl R.; Mendoza-Camberos, Antonio; Pérez-Vertti, Arturo

    2018-05-01

    We estimated the radiated seismic energy (ES) of 65 earthquakes located in the south-central region of the Gulf of California. Most of these events occurred along active transform faults that define the Pacific-North America plate boundary and have magnitudes between M3.3 and M5.9. We corrected the spectral records for attenuation using nonparametric S-wave attenuation functions determined with the whole data set. The path effects were isolated from the seismic source using a spectral inversion. We computed radiated seismic energy of the earthquakes by integrating the square velocity source spectrum and estimated their apparent stresses. We found that most events have apparent stress between 3 × 10-4 and 3 MPa. Model independent estimates of the ratio between seismic energy and moment (ES/M0) indicates that this ratio is independent of earthquake size. We conclude that in general the apparent stress is low (σa < 3 MPa) in the south-central and southern Gulf of California.

  16. Relative Prevalence of Grapevine Leafroll-Associated Virus Species in Wine Grape-Growing Regions of California.

    Directory of Open Access Journals (Sweden)

    Abhineet M Sharma

    Full Text Available Some diseases manifest as one characteristic set of symptoms to the host, but can be caused by multiple pathogens. Control treatments based on plant symptoms can make it difficult to effectively manage such diseases, as the biology of the underlying pathogens can vary. Grapevine leafroll disease affects grapes worldwide, and is associated with several viral species in the family Closteroviridae. Whereas some of the viruses associated with this disease are transmitted by insect vectors, others are only graft-transmissible. In three regions of California, we surveyed vineyards containing diseased vines and screened symptomatic plants for all known viral species associated with grapevine leafroll disease. Relative incidence of each virus species differed among the three regions regions, particularly in relation to species with known vectors compared with those only known to be graft-transmitted. In one region, the pathogen population was dominated by species not known to have an insect vector. In contrast, populations in the other surveyed regions were dominated by virus species that are vector-transmissible. Our survey did not detect viruses associated with grapevine leafroll disease at some sites with characteristic disease symptoms. This could be explained either by undescribed genetic diversity among these viruses that prevented detection with available molecular tools at the time the survey was performed, or a misidentification of visual symptoms that may have had other underlying causes. Based on the differences in relative prevalence of each virus species among regions and among vineyards within regions, we expect that region and site-specific management strategies are needed for effective disease control.

  17. Partnering with K-12 Education in Building Healthy, Sustainable, and Competitive Regions: A California Policy Symposium. Proceedings Summary & Next Steps

    Science.gov (United States)

    Vincent, Jeff; McKoy, Deborah; Alex, Ken; Mitchell, Connie; Moore, Kathleen

    2013-01-01

    On December 6, 2012, UC Berkeley's Center for Cities & Schools, in collaboration with the California Department of Education, California Department of Public Health, Governor's Office of Planning and Research, Strategic Growth Council, and Health in All Policies Task Force, brought together leaders from across California to discuss the…

  18. Status and understanding of groundwater quality in the Sierra Nevada Regional study unit, 2008: California GAMA Priority Basin Project

    Science.gov (United States)

    Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    Groundwater quality in the Sierra Nevada Regional (SNR) study unit was investigated as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Program Priority Basin Project. The study was designed to provide statistically unbiased assessments of the quality of untreated groundwater within the primary aquifer system of the Sierra Nevada. The primary aquifer system for the SNR study unit was delineated by the depth intervals over which wells in the State of California’s database of public drinking-water supply wells are open or screened. Two types of assessments were made: (1) a status assessment that described the current quality of the groundwater resource, and (2) an evaluation of relations between groundwater quality and potential explanatory factors that represent characteristics of the primary aquifer system. The assessments characterize untreated groundwater quality, rather than the quality of treated drinking water delivered to consumers by water distributors.

  19. Estimating criteria pollutant emissions using the California Regional Multisector Air Quality Emissions (CA-REMARQUE model v1.0

    Directory of Open Access Journals (Sweden)

    C. B. Zapata

    2018-04-01

    Full Text Available The California Regional Multisector Air Quality Emissions (CA-REMARQUE model is developed to predict changes to criteria pollutant emissions inventories in California in response to sophisticated emissions control programs implemented to achieve deep greenhouse gas (GHG emissions reductions. Two scenarios for the year 2050 act as the starting point for calculations: a business-as-usual (BAU scenario and an 80 % GHG reduction (GHG-Step scenario. Each of these scenarios was developed with an energy economic model to optimize costs across the entire California economy and so they include changes in activity, fuels, and technology across economic sectors. Separate algorithms are developed to estimate emissions of criteria pollutants (or their precursors that are consistent with the future GHG scenarios for the following economic sectors: (i on-road, (ii rail and off-road, (iii marine and aviation, (iv residential and commercial, (v electricity generation, and (vi biorefineries. Properly accounting for new technologies involving electrification, biofuels, and hydrogen plays a central role in these calculations. Critically, criteria pollutant emissions do not decrease uniformly across all sectors of the economy. Emissions of certain criteria pollutants (or their precursors increase in some sectors as part of the overall optimization within each of the scenarios. This produces nonuniform changes to criteria pollutant emissions in close proximity to heavily populated regions when viewed at 4 km spatial resolution with implications for exposure to air pollution for those populations. As a further complication, changing fuels and technology also modify the composition of reactive organic gas emissions and the size and composition of particulate matter emissions. This is most notably apparent through a comparison of emissions reductions for different size fractions of primary particulate matter. Primary PM2.5 emissions decrease by 4 % in the GHG

  20. Estimating criteria pollutant emissions using the California Regional Multisector Air Quality Emissions (CA-REMARQUE) model v1.0

    Science.gov (United States)

    Zapata, Christina B.; Yang, Chris; Yeh, Sonia; Ogden, Joan; Kleeman, Michael J.

    2018-04-01

    The California Regional Multisector Air Quality Emissions (CA-REMARQUE) model is developed to predict changes to criteria pollutant emissions inventories in California in response to sophisticated emissions control programs implemented to achieve deep greenhouse gas (GHG) emissions reductions. Two scenarios for the year 2050 act as the starting point for calculations: a business-as-usual (BAU) scenario and an 80 % GHG reduction (GHG-Step) scenario. Each of these scenarios was developed with an energy economic model to optimize costs across the entire California economy and so they include changes in activity, fuels, and technology across economic sectors. Separate algorithms are developed to estimate emissions of criteria pollutants (or their precursors) that are consistent with the future GHG scenarios for the following economic sectors: (i) on-road, (ii) rail and off-road, (iii) marine and aviation, (iv) residential and commercial, (v) electricity generation, and (vi) biorefineries. Properly accounting for new technologies involving electrification, biofuels, and hydrogen plays a central role in these calculations. Critically, criteria pollutant emissions do not decrease uniformly across all sectors of the economy. Emissions of certain criteria pollutants (or their precursors) increase in some sectors as part of the overall optimization within each of the scenarios. This produces nonuniform changes to criteria pollutant emissions in close proximity to heavily populated regions when viewed at 4 km spatial resolution with implications for exposure to air pollution for those populations. As a further complication, changing fuels and technology also modify the composition of reactive organic gas emissions and the size and composition of particulate matter emissions. This is most notably apparent through a comparison of emissions reductions for different size fractions of primary particulate matter. Primary PM2.5 emissions decrease by 4 % in the GHG-Step scenario vs

  1. Detection of Rickettsia Species in Fleas Collected from Cats in Regions Endemic and Nonendemic for Flea-Borne Rickettsioses in California.

    Science.gov (United States)

    Billeter, Sarah A; Diniz, Pedro Paulo Vissotto de Paiva; Jett, Lindsey A; Wournell, Andrea L; Kjemtrup, Anne M; Padgett, Kerry A; Yoshimizu, Melissa Hardstone; Metzger, Marco E; Barr, Margaret C

    2016-03-01

    Rickettsia typhi, transmitted by rat fleas, causes most human flea-borne rickettsioses worldwide. Another rickettsia, Rickettsia felis, found in cat fleas, Ctenocephalides felis, has also been implicated as a potential human pathogen. In the continental United States, human cases of flea-borne rickettsioses are reported primarily from the southern regions of Texas and California where the cat flea is considered the principal vector. In California, more than 90% of locally acquired human cases are reported from suburban communities within Los Angeles and Orange counties despite the almost ubiquitous presence of cat fleas and their hosts throughout the state. The objective of this study is to assess the presence and infection rate of Rickettsia species in cat fleas from selected endemic and nonendemic regions of California. Cat fleas were collected from cats in Los Angeles County (endemic region) and Sacramento and Contra Costa counties (nonendemic region). Sequencing of 17 amplicons confirmed the presence of R. felis in both the endemic and non-endemic regions with a calculated maximum likelihood estimation of 131 and 234 per 1000 fleas, respectively. R. typhi was not detected in any flea pools. Two R. felis-like genotypes were also detected in fleas from Los Angeles County; Genotype 1 was detected in 1 flea pool and Genotype 2 was found in 10 flea pools. Genotype 1 was also detected in a single flea pool from Sacramento County. Results from this study show that R. felis is widespread in cat flea populations in both flea-borne rickettsioses endemic and nonendemic regions of California, suggesting that a high prevalence of this bacterium in cat fleas does not predispose to increased risk of human infection. Further studies are needed to elucidate the role of R. felis and the two R. felis-like organisms as etiologic agents of human flea-borne rickettsioses in California.

  2. Preliminary maps of Quaternary deposits and liquefaction susceptibility, nine-county San Francisco Bay region, California: a digital database

    Science.gov (United States)

    Knudsen, Keith L.; Sowers, Janet M.; Witter, Robert C.; Wentworth, Carl M.; Helley, Edward J.; Nicholson, Robert S.; Wright, Heather M.; Brown, Katherine H.

    2000-01-01

    This report presents a preliminary map and database of Quaternary deposits and liquefaction susceptibility for the nine-county San Francisco Bay region, together with a digital compendium of ground effects associated with past earthquakes in the region. The report consists of (1) a spatial database of fivedata layers (Quaternary deposits, quadrangle index, and three ground effects layers) and two text layers (a labels and leaders layer for Quaternary deposits and for ground effects), (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map, liquefaction interpretation, and the ground effects compendium, and (4) the databse description pamphlet. The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment. This new map provides a modern and regionally consistent treatment of Quaternary surficial deposits that builds on the pioneering mapping of Helley and Lajoie (Helley and others, 1979) and such intervening work as Atwater (1982), Helley and others (1994), and Helley and Graymer (1997a and b). Like these earlier studies, the current mapping uses geomorphic expression, pedogenic soils, and inferred depositional environments to define and distinguish the map units. In contrast to the twelve map units of Helley and Lajoie, however, this new map uses a complex stratigraphy of some forty units, which permits a more realistic portrayal of the Quaternary depositional system. The two colored maps provide a regional summary of the new mapping at a scale of 1:275,000, a scale that is sufficient to show the general distribution and relationships of

  3. ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI IMPOR BAJA DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Jhonson Agustinus Pasaribu

    2017-06-01

    Full Text Available Impor baja terus mengalami peningkatan dari tahun 1980-2012, hal ini disebabkan karena tingkat produksi baja tidak mampu mengimbangi dan memenuhi tingkat konsumsi baja. Penelitian ini bertujuan untuk menganalisis faktor-faktor yang mempengaruhi impor baja di Indonesia. Metode analisis yang digunakan adalah Error Corection Model (ECM. Pengujian secara parsial digunakan uji t-statistik dan pengujian secara serempak digunakan uji F-statistik. Hasil penelitian ini menunjukan bahwa Produksi baja berpengaruh negatif dan signifikan terhadap impor baja dalam jangka panjang dan jangka pendek. Konsumsi baja menunjukan pengaruh positif dan signifikan terhadap impor baja dalam jangka panjang dan jangka pendek. Gross Domestic Product (GDP menunjukan pengaruh yang negatif dan tidak signifikan terhadap impor baja dalam jangka panjang dan jangka pendek. Nilai tukar rupiah (Kurs menunjukan pengaruh yang positif dan tidak signifikan terhadap impor baja dalam jangka panjang dan jangka pendek.  The steel import keep having enhancement from 1980 to 2012, it’s because of steel production level can’t fulfill the steel consumption level. If the high level of the steel import volume continues, domestic steel industries will run into a low impact for Indonesian’s economy. The goal of this research analize the affecting factors of steel import in Indonesia. The analytical method use the Error Correction Model (ECM. The partial test use t-statistic and the simultan test use F-statistic. The results showed that the steel production has negative and significant effect on steel import in the long term and short term. The steel consumption has positive and significant effect on steel import in the long term and short term. The Gross Domestic Product (GDP has negative and not significant effect on steel import in the long term and short term. The exchange rate indicates positive and not significant effect on steel import in the long term and short term.

  4. Strongly-sheared wind-forced currents in the nearshore regions of the central Southern California Bight

    Science.gov (United States)

    Noble, Marlene A.; Rosenberger, Kurt; Robertson, George L.

    2015-01-01

    Contrary to many previous reports, winds do drive currents along the shelf in the central portion of the Southern California Bight (SCB). Winds off Huntington Beach CA are the dominant forcing for currents over the nearshore region of the shelf (water depths less than 20 m). Winds control about 50–70% of the energy in nearshore alongshelf surface currents. The wind-driven current amplitudes are also anomalously high. For a relatively weak 1 dyne/cm2 wind stress, the alongshelf surface current amplitudes in this region can reach 80 cm/s or more. Mid-depth current amplitudes for the same wind stress are around 30–40 cm/s. These wind-driven surface current amplitudes are much larger than previously measured over other nearshore shelf regions, perhaps because this program is one of the few that measured currents within a meter of the surface. The near-bed cross-shelf currents over the nearshore region of the Huntington Beach shelf have an Ekman response to winds in that they upwell (downwell) for down (up) coast winds. This response disappears further offshore. Hence, there is upwelling in the SCB, but it does not occur across the entire shelf. Subthermocline water in the nearshore region that may contain nutrients and plankton move onshore when winds are southeastward, but subthermocline water over the shelf break is not transported to the beach. The currents over the outer shelf are not predominately controlled by winds, consistent with previous reports. Instead, they are mainly driven by cross-shelf pressure gradients that are independent of local wind stress.

  5. Volcanic unrest and hazard communication in Long Valley Volcanic Region, California

    Science.gov (United States)

    Hill, David P.; Mangan, Margaret T.; McNutt, Stephen R.

    2017-01-01

    The onset of volcanic unrest in Long Valley Caldera, California, in 1980 and the subsequent fluctuations in unrest levels through May 2016 illustrate: (1) the evolving relations between scientists monitoring the unrest and studying the underlying tectonic/magmatic processes and their implications for geologic hazards, and (2) the challenges in communicating the significance of the hazards to the public and civil authorities in a mountain resort setting. Circumstances special to this case include (1) the sensitivity of an isolated resort area to media hype of potential high-impact volcanic and earthquake hazards and its impact on potential recreational visitors and the local economy, (2) a small permanent population (~8000), which facilitates face-to-face communication between scientists monitoring the hazard, civil authorities, and the public, and (3) the relatively frequent turnover of people in positions of civil authority, which requires a continuing education effort on the nature of caldera unrest and related hazards. Because of delays associated with communication protocols between the State and Federal governments during the onset of unrest, local civil authorities and the public first learned that the U.S. Geological Survey was about to release a notice of potential volcanic hazards associated with earthquake activity and 25-cm uplift of the resurgent dome in the center of the caldera through an article in the Los Angeles Times published in May 1982. The immediate reaction was outrage and denial. Gradual acceptance that the hazard was real required over a decade of frequent meetings between scientists and civil authorities together with public presentations underscored by frequently felt earthquakes and the onset of magmatic CO2 emissions in 1990 following a 11-month long earthquake swarm beneath Mammoth Mountain on the southwest rim of the caldera. Four fatalities, one on 24 May 1998 and three on 6 April 2006, underscored the hazard posed by the CO2

  6. Characterization of Quaternary and suspected Quaternary faults, regional studies, Nevada and California

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.E.; Bucknam, R.C.; Crone, A.J.; Haller, K.M.; Machette, M.N.; Personius, S.F.; Barnhard, T.P.; Cecil, M.J.; Dart, R.L.

    1995-12-31

    This report presents the results of geologic studies that help define the Quaternary history of selected faults in the region around Yucca Mountain, Nevada. These results are relevant to the seismic-design basis of a potential nuclear waste repository at Yucca Mountain. The relevancy is based, in part, on a need for additional geologic data that became apparent in ongoing studies that resulted in the identification of 51 relevant and potentially relevant individual and compound faults and fault zones in the 100-km-radius region around the Yucca Mountain site. Geologic data used to characterize the regional faults and fault zones as relevant or potentially relevant seismic sources includes age and displacement information, maximum fault lengths, and minimum distances between the fault and the Yucca Mountain site. For many of the regional faults, no paleoseismic field studies have previously been conducted, and age and displacement data are sparse to nonexistent. In November 1994, the Branch of Earthquake and Landslide Hazards entered into two Memoranda of Agreement with the Yucca Mountain Project Branch to conduct field reconnaissance, analysis, and interpretation of six relevant and six potentially relevant regional faults. This report describes the results of study of those faults exclusive of those in the Pahrump-Stewart Valley-Ash Meadows-Amargosa Valley areas. We also include results of a cursory study of faults on the west flank of the Specter Range and in the northern part of the Last Chance Range. A four-phase strategy was implemented for the field study.

  7. California State Waters Map Series: offshore of San Gregorio, California

    Science.gov (United States)

    Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Watt, Janet T.; Golden, Nadine E.; Endris, Charles A.; Phillips, Eleyne L.; Hartwell, Stephen R.; Johnson, Samuel Y.; Kvitek, Rikk G.; Erdey, Mercedes D.; Bretz, Carrie K.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Dieter, Bryan E.; Chin, John L.; Cochran, Susan A.; Cochrane, Guy R.; Cochran, Susan A.

    2014-01-01

    the northern and southern parts of the map area are the result of right-lateral motion on strands of the San Gregorio Fault system. In the south, headlands near Pescadero Point have been uplifted by motion along the west strand of the San Gregorio Fault (also called the Frijoles Fault), which separates rocks of the Pigeon Point Formation south of the fault from rocks of the Purisima Formation north of the fault. The regional uplift in this map area has caused relatively shallow water depths within California's State Waters and, thus, little accommodation space for sediment accumulation. Sediment is observed offshore in the central part of the map area, in the shelter of the headlands north of the east strand of the San Gregorio Fault (also called the Coastways Fault) around Miramontes Point (about 5 km north of the map area) and also on the outer half of the California's State Waters shelf in the south where depths exceed 40 m. Sediment in the outer shelf of California's State Waters is rippled, indicating some mobility. The Offshore of San Gregorio map area lies within the cold-temperate biogeographic zone that is called either the "Oregonian province" or the "northern California ecoregion." This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, an eastern limb of the North Pacific subtropical gyre that flows from Oregon to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 350 km south of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off of central California has experienced a warming

  8. Review of wastewater problems and wastewater-management planning in the San Francisco Bay region, California

    Science.gov (United States)

    Hines, Walter G.

    1973-01-01

    The San Francisco Bay region has suffered adverse environmental effects related to the discharge of municipal-, industrial-, and agricultural- wastewater and storm-water runoff. Specific pollutional properties of theses discharges are not well understood in all cases although the toxic materials and aquatic-plant nutrients (biostimulants) found in municipal and industrial waterwater are considered to be a major cause of regional water-quality problems. Other water-quality problems in the region are commonly attributed to pesticides found in agricultural wastewater and potentially pathogenic bacteria in municipal-wastewater discharges and in storm-water runoff. The geographical distribution and magnitude of wastewater discharges in the bay region, particularly those from municipalities and industries, is largely a function of population, economic growth, and urban development. As might be expected, the total volume of wastewater has increased in a trend paralleling this growth and development. More significant, perhaps, is the fact that the total volume parameters such as BOD (biochemical oxygen demand), biostimulant concentrations, and toxicity, has increased despite large expenditures on new and improved municipal- and industrial-wastewater-treatment plants. Also, pollutant loadings from other major source, such as agriculture and storm-water runoff, have increased. At the time of writing (1972), many Federal, State, regional, and local agencies are engaged in a comprehensive wastewater-management-planning effort for the entire bay region. Initial objectives of this planning effort are: (1) the consolidation and coordination of loosely integrated wastewater-management facilities and (2) the elimination of wastewater discharges to ecologically sensitive areas, such as fresh-water streams and shallow extremities of San Francisco Bay. There has been some investigation of potential long-range wastewater-management alternatives based upon disposal in deep water in the

  9. A Gravity data along LARSE (Los Angeles Regional Seismic Experiment) Line II, Southern California

    Science.gov (United States)

    Wooley, R.J.; Langenheim, V.E.

    2001-01-01

    The U.S. Geological Survey conducted a detailed gravity study along part of the Los Angeles Regional Seismic Experiment (LARSE) transect across the San Fernando Basin and Transverse Ranges to help characterize the structure underlying this area. 249 gravity measurements were collected along the transect and to augment regional coverage near the profile. An isostatic gravity low of 50-60 mGal reflects the San Fernando-East Ventura basin. Another prominent isostatic gravity with an amplitude of 30 mGal marks the Antelope Valley basin. Gravity highs occur over the Santa Monica Mountains and the Transverse Ranges. The highest isostatic gravity values coincide with outcrops of Pelona schist.

  10. Crustal structure of the coastal and marine San Francisco Bay region, California

    Science.gov (United States)

    Parsons, Tom

    2002-01-01

    As of the time of this writing, the San Francisco Bay region is home to about 6.8 million people, ranking fifth among population centers in the United States. Most of these people live on the coastal lands along San Francisco Bay, the Sacramento River delta, and the Pacific coast. The region straddles the tectonic boundary between the Pacific and North American Plates and is crossed by several strands of the San Andreas Fault system. These faults, which are stressed by about 4 cm of relative plate motion each year, pose an obvious seismic hazard.

  11. Using NASA's Giovanni System to Simulate Time-Series Stations in the Outflow Region of California's Eel River

    Science.gov (United States)

    Acker, James G.; Shen, Suhung; Leptoukh, Gregory G.; Lee, Zhongping

    2012-01-01

    Oceanographic time-series stations provide vital data for the monitoring of oceanic processes, particularly those associated with trends over time and interannual variability. There are likely numerous locations where the establishment of a time-series station would be desirable, but for reasons of funding or logistics, such establishment may not be feasible. An alternative to an operational time-series station is monitoring of sites via remote sensing. In this study, the NASA Giovanni data system is employed to simulate the establishment of two time-series stations near the outflow region of California s Eel River, which carries a high sediment load. Previous time-series analysis of this location (Acker et al. 2009) indicated that remotely-sensed chl a exhibits a statistically significant increasing trend during summer (low flow) months, but no apparent trend during winter (high flow) months. Examination of several newly-available ocean data parameters in Giovanni, including 8-day resolution data, demonstrates the differences in ocean parameter trends at the two locations compared to regionally-averaged time-series. The hypothesis that the increased summer chl a values are related to increasing SST is evaluated, and the signature of the Eel River plume is defined with ocean optical parameters.

  12. Geothermal direct heat use: market potential/penetration analysis for Federal Region IX (Arizona, California, Hawaii, Nevada)

    Energy Technology Data Exchange (ETDEWEB)

    Powell, W.; Tang, K. (eds.)

    1980-05-01

    A preliminary study was made of the potential for geothermal direct heat use in Arizona, California, Hawaii, and Nevada (Federal Region IX). The analysis for each state was performed by a different team, located in that state. For each state, the study team was asked to: (1) define the resource, based on the latest available data; (2) assess the potential market growth for geothermal energy; and (3) estimate the market penetration, projected to 2020. Each of the four states of interest in this study is unique in its own way. Rather than impose the same assumptions as to growth rates, capture rates, etc. on all of the study teams, each team was asked to use the most appropriate set of assumptions for its state. The results, therefore, should reflect the currently accepted views within each state. The four state reports comprise the main portion of this document. A brief regional overview section was prepared by the Jet Propulsion Laboratory, following completion of the state reports.

  13. Ammonia and Methane Dairy Emission Plumes in the San Joaquin Valley of California from Individual Feedlot to Regional Scales

    Science.gov (United States)

    Miller, David J.; Sun, Kang; Pan, Da; Zondlo, Mark A.; Nowak, John B.; Liu, Zhen; Diskin, Glenn; Sachse, Glen; Beyersdorf, Andreas; Ferrare, Richard; hide

    2015-01-01

    Agricultural ammonia (NH3) emissions are highly uncertain, with high spatiotemporal variability and a lack of widespread in situ measurements. Regional NH3 emission estimates using mass balance or emission ratio approaches are uncertain due to variable NH3 sources and sinks as well as unknown plume correlations with other dairy source tracers. We characterize the spatial distributions of NH3 and methane (CH4) dairy plumes using in situ surface and airborne measurements in the Tulare dairy feedlot region of the San Joaquin Valley, California, during the NASA Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality 2013 field campaign. Surface NH3 and CH4 mixing ratios exhibit large variability with maxima localized downwind of individual dairy feedlots. The geometric mean NH3:CH4 enhancement ratio derived from surface measurements is 0.15 +/- 0.03 ppmv ppmv-1. Individual dairy feedlots with spatially distinct NH3 and CH4 source pathways led to statistically significant correlations between NH3 and CH4 in 68% of the 69 downwind plumes sampled. At longer sampling distances, the NH3:CH4 enhancement ratio decreases 20-30%, suggesting the potential for NH3 deposition as a loss term for plumes within a few kilometers downwind of feedlots. Aircraft boundary layer transect measurements directly above surface mobile measurements in the dairy region show comparable gradients and geometric mean enhancement ratios within measurement uncertainties, even when including NH3 partitioning to submicron particles. Individual NH3 and CH4 plumes sampled at close proximity where losses are minimal are not necessarily correlated due to lack of mixing and distinct source pathways. Our analyses have important implications for constraining NH3 sink and plume variability influences on regional NH3 emission estimates and for improving NH3 emission inventory spatial allocations.

  14. A probabilistic view of chaparral and forest fire regimes in southern California and northern Baja California

    Science.gov (United States)

    Richard A. Minnich; Ernesto. Franco-Vizcaíno

    2009-01-01

    Fire suppression in industrialized countries encourages massive smoke emissions from high-intensity fires as a result of two inextricably related processes under current suppression policies: the nonrandom occurrence of vegetation fires in extreme weather states and the anomalous accumulation of spatially homogenous fuels. We propose as an organizing idea that the...

  15. The Role of Rift Obliquity in Formation of the Gulf of California

    Science.gov (United States)

    Bennett, Scott Edmund Kelsey

    The Gulf of California illustrates how highly oblique rift geometries, where transform faults are kinematically linked to large-offset normal faults in adjacent pull-apart basins, enhance the ability of continental lithosphere to rupture and, ultimately, hasten the formation of new oceanic basins. The Gulf of California rift has accommodated oblique divergence of the Pacific and North America tectonic plates in northwestern Mexico since Miocene time. Due to its infancy, the rifted margins of the Gulf of California preserve a rare onshore record of early continental break-up processes from which to investigate the role of rift obliquity in strain localization. Using new high-precision paleomagnetic vectors from tectonically stable sites in north-central Baja California, I compile a paleomagnetic transect of Miocene ignimbrites across northern Baja California and Sonora that reveals the timing and distribution of dextral shear associated with inception of this oblique rift. I integrate detailed geologic mapping, basin analysis, and geochronology of pre-rift and syn-rift volcanic units to determine the timing of fault activity on Isla Tiburon, a proximal onshore exposure of the rifted North America margin, adjacent to the axis of the Gulf of California. The onset of strike-slip faulting on Isla Tiburon, ca. 8 - 7 Ma, was synchronous with the onset of transform faulting along a significant length of the nascent plate boundary within the rift. This tectonic transition coincides with a clockwise azimuthal shift in Pacific-North America relative motion that increased rift obliquity. I constrain the earliest marine conditions on southwest Isla Tiburon to ca. 6.4 - 6.0 Ma, coincident with a regional latest Miocene marine incursion in the northern proto-Gulf of California. This event likely flooded a narrow, incipient topographic depression along a ˜650 km-long portion of the latest Miocene plate boundary and corresponds in time and space with formation of a newly

  16. Effect of faulting on ground-water movement in the Death Valley region, Nevada and California

    International Nuclear Information System (INIS)

    Faunt, C.C.

    1997-01-01

    This study characterizes the hydrogeologic system of the Death Valley region, an area covering approximately 100,000 square kilometers. The study also characterizes the effects of faults on ground-water movement in the Death Valley region by synthesizing crustal stress, fracture mechanics,a nd structural geologic data. The geologic conditions are typical of the Basin and Range Province; a variety of sedimentary and igneous intrusive and extrusive rocks have been subjected to both compressional and extensional deformation. Faulting and associated fracturing is pervasive and greatly affects ground-water flow patterns. Faults may become preferred conduits or barriers to flow depending on whether they are in relative tension, compression, or shear and other factors such as the degree of dislocations of geologic units caused by faulting, the rock types involved, the fault zone materials, and the depth below the surface. The current crustal stress field was combined with fault orientations to predict potential effects of faults on the regional ground-water flow regime. Numerous examples of fault-controlled ground-water flow exist within the study area. Hydrologic data provided an independent method for checking some of the assumptions concerning preferential flow paths. 97 refs., 20 figs., 5 tabs

  17. Assessing the combined effect of dams and climate warming on streamflow in California's Sierra Nevada for regional-scale adaptation

    Science.gov (United States)

    Rheinheimer, D. E.; Viers, J. H.

    2012-12-01

    Dams and their operations harm river ecosystems, in part by altering the natural flow regimes that those ecosystems depend on. In the multi-reservoir water management systems of California's Sierra Nevada, greater emphasis is being placed on re-operating existing reservoir systems to recover downstream ecosystems. However, climate change is changing inflow patterns, affecting both ecosystems and traditional water system benefits across the region. As new reservoir operation schemes will be needed to manage for natural resources management objectives at the regional scale, characterizing historical and future environmental impacts of current operations across the region can aid in prioritizing planning efforts. We used a coarse-scale water resources simulation model developed for the western Sierra Nevada to explore the independent and combined effects of dams and climate warming on the flow regime directly below reservoirs, the focal point for instream flow requirements in operations licenses. We quantified changes to mean annual flow, annual low flow duration, annual runoff centroid timing, and weekly rate of decrease under binary combinations of management (unregulated/regulated) and climate (historical/future) conditions. We demonstrate that although rivers in the Sierra Nevada are currently managed in ways that are harmful to instream ecosystems, and that streamflow effects of operations are typically much worse than climate change effects, there are signals that reservoirs can potentially be used to help adapt to some of climate changes harmful effects with little additional effort in some cases. This study is the first step toward a better understanding of the environmental costs from and opportunities afforded by the current stock of reservoirs in a large hydroregion under changing social and environmental conditions.

  18. La baja utilidad de la determinación del ADN del VPH en la región distal de la uretra masculina Low usefulness of HPV DNA determination in the distal region of the male urethra

    Directory of Open Access Journals (Sweden)

    Ahideé G Leyva-López

    2003-01-01

    cervical intraepithelial neoplasia. MATERIAL AND METHODS: A cross-sectional study was conducted from October 1997 to August 1998, among 200 men aged 17 to 64 years referred to the Oncology Department of the National Institute of Perinatology in Mexico City. A physical examination of the penis (penoscopy was performed after applying 3-5% acetic acid. A colposcope was used to identify acetowhite areas and vascular abnormalities associated with HPV infection. HPV DNA was detected by PCR and reverse line hybridization. The exploratory and univariant statistical analysis was made with the package Stata V6.0. RESULTS: The beta-globin gene was present in 93.5% (n=187 of the 200 urethral exfoliated cell samples collected. HPV DNA was detected in only 2% (4/187 of the study subjects. Penoscopy data showed the presence of acetowhite areas in 43% (81/187 of subjects. CONCLUSIONS: Study findings show that the presence of HPV DNA in urethra is uncommon, as has been reported in several previous studies. Research is needed to evaluate the presence of HPV DNA in the coronal sulcus, as compared with the distal urethral region.

  19. High-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region, California

    Science.gov (United States)

    Ponce, D. A.; Mangan, M.; McPhee, D.

    2013-12-01

    A new high-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region greatly enhances previous magnetic interpretations that were based on older, low-resolution, and regional aeromagnetic data sets and provides new insights into volcano-tectonic processes. The surveyed area covers a 8,750 km2 NNW-trending swath situated between the Sierra Nevada to the west and the Basin and Range Province to the east. The surveyed area includes the volcanic centers of Mono Lake, Mono-Inyo Craters, Mammoth Mountain, Devils Postpile, and Long Valley Caldera. The NW-trending eastern Sierra frontal fault zone crosses through the study area, including the active Mono Lake, Silver Lake, Hartley Springs, Laurel Creek, and Hilton Creek faults. Over 6,000 line-kilometers of aeromagnetic data were collected at a constant terrain clearance of 150 m, a flight-line spacing of 400 m, and a tie-line spacing of 4 km. Data were collected via helicopter with an attached stinger housing a magnetic sensor using a Scintrex CS-3 cesium magnetometer. In the northern part of the survey area, data improve the magnetic resolution of the individual domes and coulees along Mono Craters and a circular shaped magnetic anomaly that coincides with a poorly defined ring fracture mapped by Kistler (1966). Here, aeromagnetic data combined with other geophysical data suggests that Mono Craters may have preferentially followed a pre-existing plutonic basement feature that may have controlled the sickle shape of the volcanic chain. In the northeastern part of the survey, aeromagnetic data reveal a linear magnetic anomaly that correlates with and extends a mapped fault. In the southern part of the survey, in the Sierra Nevada block just south of Long Valley Caldera, aeromagnetic anomalies correlate with NNW-trending Sierran frontal faults rather than to linear NNE-trends observed in recent seismicity over the last 30 years. These data provide an important framework for the further analysis of the

  20. Hydrothermal vent fields discovered in the southern Gulf of California clarify role of habitat in augmenting regional diversity.

    Science.gov (United States)

    Goffredi, Shana K; Johnson, Shannon; Tunnicliffe, Verena; Caress, David; Clague, David; Escobar, Elva; Lundsten, Lonny; Paduan, Jennifer B; Rouse, Greg; Salcedo, Diana L; Soto, Luis A; Spelz-Madero, Ronald; Zierenberg, Robert; Vrijenhoek, Robert

    2017-07-26

    Hydrothermal vent communities are distributed along mid-ocean spreading ridges as isolated patches. While distance is a key factor influencing connectivity among sites, habitat characteristics are also critical. The Pescadero Basin (PB) and Alarcón Rise (AR) vent fields, recently discovered in the southern Gulf of California, are bounded by previously known vent localities (e.g. Guaymas Basin and 21° N East Pacific Rise); yet, the newly discovered vents differ markedly in substrata and vent fluid attributes. Out of 116 macrofaunal species observed or collected, only three species are shared among all four vent fields, while 73 occur at only one locality. Foundation species at basalt-hosted sulfide chimneys on the AR differ from the functional equivalents inhabiting sediment-hosted carbonate chimneys in the PB, only 75 km away. The dominant species of symbiont-hosting tubeworms and clams, and peripheral suspension-feeding taxa, differ between the sites. Notably, the PB vents host a limited and specialized fauna in which 17 of 26 species are unknown at other regional vents and many are new species. Rare sightings and captured larvae of the 'missing' species revealed that dispersal limitation is not responsible for differences in community composition at the neighbouring vent localities. Instead, larval recruitment-limiting habitat suitability probably favours species differentially. As scenarios develop to design conservation strategies around mining of seafloor sulfide deposits, these results illustrate that models encompassing habitat characteristics are needed to predict metacommunity structure. © 2017 The Authors.

  1. 3-D P- and S-wave velocity structure and low-frequency earthquake locations in the Parkfield, California region

    Science.gov (United States)

    Zeng, Xiangfang; Thurber, Clifford H.; Shelly, David R.; Harrington, Rebecca M.; Cochran, Elizabeth S.; Bennington, Ninfa L.; Peterson, Dana; Guo, Bin; McClement, Kara

    2016-01-01

    To refine the 3-D seismic velocity model in the greater Parkfield, California region, a new data set including regular earthquakes, shots, quarry blasts and low-frequency earthquakes (LFEs) was assembled. Hundreds of traces of each LFE family at two temporary arrays were stacked with time–frequency domain phase weighted stacking method to improve signal-to-noise ratio. We extend our model resolution to lower crustal depth with LFE data. Our result images not only previously identified features but also low velocity zones (LVZs) in the area around the LFEs and the lower crust beneath the southern Rinconada Fault. The former LVZ is consistent with high fluid pressure that can account for several aspects of LFE behaviour. The latter LVZ is consistent with a high conductivity zone in magnetotelluric studies. A new Vs model was developed with S picks that were obtained with a new autopicker. At shallow depth, the low Vs areas underlie the strongest shaking areas in the 2004 Parkfield earthquake. We relocate LFE families and analyse the location uncertainties with the NonLinLoc and tomoDD codes. The two methods yield similar results.

  2. Consideraciones sobre el hidrocefalo de baja presion

    Directory of Open Access Journals (Sweden)

    E. Herskovits

    1976-12-01

    Full Text Available Se analizan las condiciones fisiopatológicas del sindrome de hidrocéfalo de presión normal. De un grupo de 21 pacientes con sintomatologia clínica correspondiente a esta entidad, se seleccionan 10 que presentan un diagnóstico clínico, radiológico y cisternográfico indudable de la entidad en estudio. Se observó que, a pesar de esta selección solamente un 50% de ellos se vió beneficiado con la colocación de una válvula de baja presión. Surge entonces la hipotésis de que este cuadro es un sindrome multicausal; que por un proceso fisiopatogenico común produce un cuadro clínico, radiológico y cisternográfico similar y que serían beneficiados únicamente aquellos enfermos en los que se soluciona el problema mecánico.

  3. Assessing Drought Impacts on Water Storage using GRACE Satellites and Regional Groundwater Modeling in the Central Valley of California

    Science.gov (United States)

    Scanlon, B. R.; Zhang, Z.; Save, H.; Faunt, C. C.; Dettinger, M. D.

    2015-12-01

    Increasing concerns about drought impacts on water resources in California underscores the need to better understand effects of drought on water storage and coping strategies. Here we use a new GRACE mascons solution with high spatial resolution (1 degree) developed at the Univ. of Texas Center for Space Research (CSR) and output from the most recent regional groundwater model developed by the U.S. Geological Survey to evaluate changes in water storage in response to recent droughts. We also extend the analysis of drought impacts on water storage back to the 1980s using modeling and monitoring data. The drought has been intensifying since 2012 with almost 50% of the state and 100% of the Central Valley under exceptional drought in 2015. Total water storage from GRACE data declined sharply during the current drought, similar to the rate of depletion during the previous drought in 2007 - 2009. However, only 45% average recovery between the two droughts results in a much greater cumulative impact of both droughts. The CSR GRACE Mascons data offer unprecedented spatial resolution with no leakage to the oceans and no requirement for signal restoration. Snow and reservoir storage declines contribute to the total water storage depletion estimated by GRACE with the residuals attributed to groundwater storage. Rates of groundwater storage depletion are consistent with the results of regional groundwater modeling in the Central Valley. Traditional approaches to coping with these climate extremes has focused on surface water reservoir storage; however, increasing conjunctive use of surface water and groundwater and storing excess water from wet periods in depleted aquifers is increasing in the Central Valley.

  4. Ambient Noise Tomography at Regional and Local Scales in Southern California using Rayleigh Wave Phase Dispersion and Ellipticity

    Science.gov (United States)

    Berg, E.; Lin, F. C.; Qiu, H.; Wang, Y.; Allam, A. A.; Clayton, R. W.; Ben-Zion, Y.

    2017-12-01

    Rayleigh waves extracted from cross-correlations of ambient seismic noise have proven useful in imaging the shallow subsurface velocity structure. In contrast to phase velocities, which are sensitive to slightly deeper structure, Rayleigh wave ellipticity (H/V ratios) constrains the uppermost crust. We conduct Rayleigh wave ellipticity and phase dispersion measurements in Southern California between 6 and 18 second periods, computed from multi-component ambient noise cross-correlations using 315 stations across the region in 2015. Because of the complimentary sensitivity of phase velocity and H/V, this method enables simple and accurate resolution of near-surface geological features from the surface to 20km depth. We compare the observed H/V ratios and phase velocities to predictions generated from the current regional models (SCEC UCVM), finding strong correspondence where the near-surface structure is well-resolved by the models. This includes high H/V ratios in the LA Basin, Santa Barbara Basin and Salton Trough; and low ratios in the San Gabriel, San Jacinto and southern Sierra Nevada mountains. Disagreements in regions such as the Western Transverse Ranges, Salton Trough, San Jacinto and Elsinore fault zones motivate further work to improve the community models. A new updated 3D isotropic model of the area is derived via a joint inversion of Rayleigh phase dispersions and H/V ratios. Additionally, we examine azimuthal dependence of the H/V ratio to ascertain anisotropy patterns for each station. Clear 180º periodicity is observed for many stations suggesting strong shallow anisotropy across the region including up to 20% along the San Andreas fault, 15% along the San Jacinto Fault and 25% in the LA Basin. To better resolve basin structures, we apply similar techniques to three dense linear geophone arrays in the San Gabriel and San Bernardino basins. The three arrays are composed by 50-125 three-component 5Hz geophones deployed for one month each with 15-25km

  5. The ophiolitic North Fork terrane in the Salmon River region, central Klamath Mountains, California

    Science.gov (United States)

    Ando, C.J.; Irwin, W.P.; Jones, D.L.; Saleeby, J.B.

    1983-01-01

    The North Fork terrane is an assemblage of ophiolitic and other oceanic volcanic and sedimentary rocks that has been internally imbricated and folded. The ophiolitic rocks form a north-trending belt through the central part of the region and consist of a disrupted sequence of homogeneous gabbro, diabase, massive to pillowed basalt, and interleaved tectonitic harzburgite. U-Pb zircon age data on a plagiogranite pod from the gabbroic unit indicate that at least this part of the igneous sequence is late Paleozoic in age.The ophiolitic belt is flanked on either side by mafic volcanic and volcaniclastic rocks, limestone, bedded chert, and argillite. Most of the chert is Triassic, including much of Late Triassic age, but chert with uncertain stratigraphic relations at one locality is Permian. The strata flanking the east side of the ophiolitic belt face eastward, and depositional contacts between units are for the most part preserved. The strata on the west side of the ophiolitic belt are more highly disrupted than those on the east side, contain chert-argillite melange, and have unproven stratigraphic relation to either the ophiolitic rocks or the eastern strata.Rocks of the North Fork terrane do not show widespread evidence of penetrative deformation at elevated temperatures, except an early tectonitic fabric in the harzburgite. Slip-fiber foliation in serpentinite, phacoidal foliation in chert and mafic rocks, scaly foliation in argillite, and mesoscopic folds in bedded chert are consistent with an interpretation of large-scale anti-formal folding of the terrane about a north-south hinge found along the ophiolitic belt, but other structural interpretations are tenable. The age of folding of North Fork rocks is constrained by the involvement of Triassic and younger cherts and crosscutting Late Jurassic plutons. Deformation in the North Fork terrane must have spanned a short period of time because the terrane is bounded structurally above and below by Middle or Late

  6. Chronology of Miocene-Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

    Science.gov (United States)

    Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.

    2007-01-01

    Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.

  7. Analisis Perbandingan Efisiensi Penggunaan Baja Ringan Pada Tiga Jenis Tipe Rangka Atap

    OpenAIRE

    DAKHI, DICE J L

    2015-01-01

    10 0404 1097 Seiring dengan perkembangan zaman, baja ringan semakin populer digunakan pada konstruksi rangka atap. Hal ini dikarenakan baja ringan jauh lebih ekonomis dibandingkan dengan baja konvensional maupun kayu. Baja ringan juga memiliki segudang kelebihan yang sangat menguntungkan sebuah konstruksi. Tahun 2013, Badan Standar Nasional mengeluarkan SNI 7971 yaitu standar untuk perencanaan struktur baja ringan (canai dingin). Dengan adanya SNI ini, diharapkan suatu st...

  8. Clean Water Act Section 319 Nonpoint Source Pollution Control Projects Grants, US EPA Region 9, 2008, California Nonpoint Source Program

    Data.gov (United States)

    U.S. Environmental Protection Agency — The California Nonpoint Source (NPS) Program allocates about $4.5 million of CWA Section 319 funding from the U.S. Environmental Protection Agency annually to...

  9. Concurrent Detection of Human Norovirus and Bacterial Pathogens in Water Samples from an Agricultural Region in Central California Coast

    Directory of Open Access Journals (Sweden)

    Peng Tian

    2017-08-01

    Full Text Available Bacterial pathogens and human norovirus (HuNoV are major cause for acute gastroenteritis caused by contaminated food and water. Public waterways can become contaminated from a variety of sources and flood after heavy rain events, leading to pathogen contamination of produce fields. We initiated a survey of several public watersheds in a major leafy green produce production region of the Central California Coast to determine the prevalence of HuNoV as well as bacterial pathogens. Moore swabs were used to collect environmental samples bi-monthly at over 30 sampling sites in the region. High prevalence of HuNoV and bacterial pathogens were detected in environmental water samples in the region. The overall detection rates of HuNoV, O157 Shiga toxin-producing Escherichia coli (STEC, non-O157 STEC, Salmonella, and Listeria were 25.58, 7.91, 9.42, 59.65, and 44.30%, respectively. The detection rates of Salmonella and L. monocytogenes were significantly higher in the spring. Fall and spring had elevated detection rates of O157 STEC. The overall detection rates of non-O157 STEC in the fall were lower than the other seasons but not significant. The overall detection rates of HuNoV were highest in fall, followed by spring and winter, with summer being lowest and significantly lower than other seasons. This study presented the first study of evaluating the correlation between the detection rate of HuNoV and the detection rates of four bacterial pathogens from environmental water. Overall, there was no significant difference in HuNoV detection rates between samples testing positive or negative for the four bacterial pathogens tested. Pathogens in animal-impacted and human-impacted areas were investigated. There were significant higher detection rates in animal-impacted areas than that of human-impacted areas for bacterial pathogens. However, there was no difference in HuNoV detection rates between these two areas. The overall detection levels of generic E

  10. Ocean climate indicators: A monitoring inventory and plan for tracking climate change in the north-central California coast and ocean region

    Science.gov (United States)

    Duncan, Benet; Higgason, Kelley; Suchanek, Tom; Largier, John; Stachowicz, Jay; Allen, Sarah; Bograd, Steven; Breen, R.; Gellerman, Holly; Hill, Tessa; Jahncke, Jaime; Johnson, Rebecca L.; Lonhart, Steve I.; Morgan, Steven; Wilkerson, Frances; Roletto, Jan

    2013-01-01

    The impacts of climate change, defined as increasing atmospheric and oceanic carbon dioxide and associated increases in average global temperature and oceanic acidity, have been observed both globally and on regional scales, such as in the North-central California coast and ocean, a region that extends from Point Arena to Point Año Nuevo and includes the Pacific coastline of the San Francisco Bay Area. Because of the high economic and ecological value of the region’s marine environment, the Gulf of the Farallones National Marine Sanctuary (GFNMS) and other agencies and organizations have recognized the need to evaluate and plan for climate change impacts. Climate change indicators can be developed on global, regional, and site-specific spatial scales, and they provide information about the presence and potential impacts of climate change. While indicators exist for the nation and for the state of California as a whole, no system of ocean climate indicators exist that specifically consider the unique characteristics of the California coast and ocean region. To that end, GFNMS collaborated with over 50 regional, federal, and state natural resource managers, research scientists, and other partners to develop a set of 2 ocean climate indicators specific to this region. A smaller working group of 13 regional partners developed monitoring goals, objectives, strategies, and activities for the indicators and recommended selected species for biological indicators, resulting in the Ocean Climate Indicators Monitoring Inventory and Plan. The working group considered current knowledge of ongoing monitoring, feasibility of monitoring, costs, and logistics in selecting monitoring activities and selected species.

  11. Conserving the Greater Sage-grouse: A social-ecological systems case study from the California-Nevada region

    Science.gov (United States)

    Duvall, Alison L; Metcalf, Alexander L.; Coates, Peter S.

    2016-01-01

    The Endangered Species Act (ESA) continues to serve as one of the most powerful and contested federal legislative mandates for conservation. In the midst of heated debates, researchers, policy makers, and conservation practitioners champion the importance of cooperative conservation and social-ecological systems approaches, which forge partnerships at multiple levels and scales to address complex ecosystem challenges. However, few real-world examples exist to demonstrate how multifaceted collaborations among stakeholders who share a common goal of conserving at-risk species may be nested within a systems framework to achieve social and ecological goals. Here, we present a case study of Greater Sage-grouse (Centrocercus urophasianus) conservation efforts in the “Bi-State” region of California and Nevada, United States. Using key-informant interviews, we explored dimensions and drivers of this landscape-scale conservation effort. Three themes emerged from the interviews, including 1) ESA action was transformed into opportunity for system-wide conservation; 2) a diverse, locally based partnership anchored collaboration and engagement across multiple levels and scales; and 3) best-available science combined with local knowledge led to “certainty of effectiveness and implementation”—the criteria used by the US Fish and Wildlife Service to evaluate conservation efforts when making listing decisions. Ultimately, collaborative conservation through multistakeholder engagement at various levels and scales led to proactive planning and implementation of conservation measures and precluded the need for an ESA listing of the Bi-State population of Greater Sage-grouse. This article presents a potent example of how a systems approach integrating policy, management, and learning can be used to successfully overcome the conflict-laden and “wicked” challenges that surround at-risk species conservation.

  12. Experiential environmental learning: A case study of innovative pedagogy in Baja Sur, Mexico

    Science.gov (United States)

    Schneller, Andrew Jon

    This mixed methods case study describes an innovative two-semester middle school environmental learning course that departs from traditional Mexican expository pedagogy through the incorporation of experiential and service learning. This research takes place in a small middle school in Pescadero, Baja California Sur, Mexico. The research approach utilized in the study adds to the handful of studies in this cross-disciplinary field by employing quantitative methodologies to measure course outcomes on student environmental knowledge, perceptions, and actions, while simultaneously qualitatively describing the behavioral, educational, environmental, and social experiences of students. This research employs Dewey's theories of experience---as well as those of more contemporary authenticity theorists---in order to identify the philosophies that advocate incorporating experiential pedagogy within the curriculum. Implications for Mexican educational policy, practical pedagogical applications, and theory are discussed.

  13. Regional systems development for geothermal energy resources: Pacific region (California and Hawaii). Task 2: Regional program monitoring and progress evaluation, topical report

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-19

    All the objectives of the regional program monitoring and progress evaluation have been met through personal contacts and the review of data. They are as follows: to determine the existing status of power plant projects and future plans; to identify major problem areas for each project (technical, financial, regulatory) that are affecting progress; and to analyze the data and to develop recommendations directed toward resolving problems. The results have been presented in a tabular summary format that is accompanied by explanatory text covering 25 projects.

  14. A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

    Energy Technology Data Exchange (ETDEWEB)

    Joan B. Blainey; Claudia C. Faunt, and Mary C. Hill

    2006-05-16

    This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.

  15. Spain: Europe's California.

    Science.gov (United States)

    Wilvert, Calvin

    1994-01-01

    Contends that, as Spain integrates into the European Economic Community, it is considered to be Europe's California. Asserts that making regional comparisons between California and Spain can be an effective teaching method. Provides comparisons in such areas as agriculture and tourism. (CFR)

  16. Riverine Nutrient Trends in the Sacramento and San Joaquin Basins, California: A Comparison to State and Regional Water Quality Policies

    Directory of Open Access Journals (Sweden)

    Brandon Schlegel

    2015-12-01

    Full Text Available doi: http://dx.doi.org/1015447/sfews.2015v13iss4art2Non-point source (NPS contaminant control strategies were initiated in California in the late 1980s under the authority of the State Porter–Cologne Act and eventually for the development of total maximum daily load (TMDL plans, under the federal Clean Water Act. Most of the NPS TMDLs developed for California’s Central Valley (CV region were related to pesticides, but not nutrients. Efforts to reduce pesticide loads and concentrations began in earnest around 1990. The NPS control strategies either encouraged or mandated the use of management practices (MPs. Although TMDLs were largely developed for pesticides, the resultant MPs might have affected the runoff of other potential contaminants (such as nutrients. This study evaluates the effect of agricultural NPS control strategies implemented in California’s CV before and between 1990 and 2013, on nutrients, by comparing trends in surface-water concentrations and loads. In general, use of MPs was encouraged during a “voluntary” period (1990 to 2004 and mandated during an “enforcement” period (2004 to 2013. Nutrient concentrations, loads, and trends were estimated by using a recently developed Weighted Regressions on Time, Discharge, and Season (WRTDS model. Sufficient total phosphorus (TP, total nitrogen (TN, and nitrate (NO3 data were available to compare the voluntary and enforcement periods for twelve sites within the lower Sacramento and San Joaquin basins. Ammonia concentrations and fluxes were evaluated at a subset of these sites. For six of these sites, flow-normalized mean annual concentrations of TP or NO3 decreased at a faster rate during the enforcement period than during the voluntary period. Concentration changes during similar years and ranges of flow conditions suggest that MPs designed for pesticides may also have reduced nutrient loads. Results show that enforceable NPS policies, and accelerated MP implementation

  17. Ecosystem feedbacks to climate change in California: Development, testing, and analysis using a coupled regional atmosphere and land-surface model (WRF3-CLM3.5)

    Energy Technology Data Exchange (ETDEWEB)

    Subin, Z.M.; Riley, W.J.; Kueppers, L.M.; Jin, J.; Christianson, D.S.; Torn, M.S.

    2010-11-01

    A regional atmosphere model [Weather Research and Forecasting model version 3 (WRF3)] and a land surface model [Community Land Model, version 3.5 (CLM3.5)] were coupled to study the interactions between the atmosphere and possible future California land-cover changes. The impact was evaluated on California's climate of changes in natural vegetation under climate change and of intentional afforestation. The ability of WRF3 to simulate California's climate was assessed by comparing simulations by WRF3-CLM3.5 and WRF3-Noah to observations from 1982 to 1991. Using WRF3-CLM3.5, the authors performed six 13-yr experiments using historical and future large-scale climate boundary conditions from the Geophysical Fluid Dynamics Laboratory Climate Model version 2.1 (GFDL CM2.1). The land-cover scenarios included historical and future natural vegetation from the Mapped Atmosphere-Plant-Soil System-Century 1 (MC1) dynamic vegetation model, in addition to a future 8-million-ha California afforestation scenario. Natural vegetation changes alone caused summer daily-mean 2-m air temperature changes of -0.7 to +1 C in regions without persistent snow cover, depending on the location and the type of vegetation change. Vegetation temperature changes were much larger than the 2-m air temperature changes because of the finescale spatial heterogeneity of the imposed vegetation change. Up to 30% of the magnitude of the summer daily-mean 2-m air temperature increase and 70% of the magnitude of the 1600 local time (LT) vegetation temperature increase projected under future climate change were attributable to the climate-driven shift in land cover. The authors projected that afforestation could cause local 0.2-1.2 C reductions in summer daily-mean 2-m air temperature and 2.0-3.7 C reductions in 1600 LT vegetation temperature for snow-free regions, primarily because of increased evapotranspiration. Because some of these temperature changes are of comparable magnitude to those

  18. Onshore and offshore apatite fission-track dating from the southern Gulf of California: Insights into the time-space evolution of the rifting

    Science.gov (United States)

    Balestrieri, Maria Laura; Ferrari, Luca; Bonini, Marco; Duque-Trujillo, Jose; Cerca, Mariano; Moratti, Giovanna; Corti, Giacomo

    2017-11-01

    We present the results of a apatite fission-track (AFT) study on intrusive rocks in the southern Gulf of California, sampled along the eastern margin of Baja California Sur (western rift margin), as well as from islands and submerged rifted blocks within the Gulf of California, and from the conjugate Mexican margin (Nayarit state). For most of the samples U-Pb zircon and 40Ar-39Ar mineral ages were already available (Duque-Trujillo et al., 2015). Coupled with the new AFT data these ages provide a more complete information on cooling after emplacement. Our samples span a wide range of ages between 5.5 ± 1.1 and 73.7 ± 5.8 Ma, and show a general spatial distribution, with late Miocene AFT ages (about 6 Ma) aligned roughly NW-SE along a narrow offshore belt, parallel to Baja California Peninsula, separating older ages on both sides. This pattern suggests that in Late Miocene, deformation due to plate transtension focused at the eastern rheological boundary of the Baja California block. Some Early Miocene AFT ages onshore Baja California could be related to plutons emplaced at shallow depths and thermal resetting associated with the onset of volcanism at 19 Ma in this part of the Peninsula. On the other hand, an early extensional event similar to that documented in the eastern Gulf cannot be ruled out in the westernmost Baja California.

  19. From continental to oceanic rifting in the Gulf of California

    Science.gov (United States)

    Ferrari, Luca; Bonini, Marco; Martín, Arturo

    2017-11-01

    The continental margin of northwestern Mexico is the youngest example of the transition from a convergent plate boundary to an oblique divergent margin that formed the Gulf of California rift. Subduction of the Farallon oceanic plate during the Cenozoic progressively brought the East Pacific Rise (EPR) toward the North America trench. In this process increasingly younger and buoyant oceanic lithosphere entered the subduction zone until subduction ended just before most of the EPR could collide with the North America continental lithosphere. The EPR segments bounding the unsubducted parts of the Farallón plate remnants (Guadalupe and Magdalena microplates) also ceased spreading (Lonsdale, 1991) and a belt of the North American plate (California and Baja California Peninsula) became coupled with the Pacific Plate and started moving northwestward forming the modern Gulf of California oblique rift (Nicholson et al., 1994; Bohannon and Parsons, 1995). The timing of the change from plate convergence to oblique divergence off western Mexico has been constrained at the middle Miocene (15-12.5 Ma) by ocean floor morphology and magnetic anomalies as well as plate tectonic reconstructions (Atwater and Severinghaus, 1989; Stock and Hodges, 1989; Lonsdale, 1991), although the onset of transtensional deformation and the amount of right lateral displacement within the Gulf region are still being studied (Oskin et al., 2001; Fletcher et al., 2007; Bennett and Oskin, 2014). Other aspects of the formation of the Gulf of California remain not well understood. At present the Gulf of California straddles the transition from continental transtension in the north to oceanic spreading in the south. Seismic reflection-refraction data indicate asymmetric continent-ocean transition across conjugate margins of rift segments (González-Fernández et al., 2005; Lizarralde et al., 2007; Miller and Lizarralde, 2013; Martín-Barajas et al., 2013). The asymmetry may be related to crustal

  20. The great 2006 heat wave over California and Nevada: Signal of an increasing trend

    Science.gov (United States)

    Gershunov, A.; Cayan, D.R.; Iacobellis, S.F.

    2009-01-01

    Most of the great California-Nevada heat waves can be classified into primarily daytime or nighttime events depending on whether atmospheric conditions are dry or humid. A rash of nighttime-accentuated events in the last decade was punctuated by an unusually intense case in July 2006, which was the largest heat wave on record (1948-2006). Generally, there is a positive trend in heat wave activity over the entire region that is expressed most strongly and clearly in nighttime rather than daytime temperature extremes. This trend in nighttime heat wave activity has intensified markedly since the 1980s and especially since 2000. The two most recent nighttime heat waves were also strongly expressed in extreme daytime temperatures. Circulations associated with great regional heat waves advect hot air into the region. This air can be dry or moist, depending on whether a moisture source is available, causing heat waves to be expressed preferentially during day or night. A remote moisture source centered within a marine region west of Baja California has been increasing in prominence because of gradual sea surface warming and a related increase in atmospheric humidity. Adding to the very strong synoptic dynamics during the 2006 heat wave were a prolonged stream of moisture from this southwestern source and, despite the heightened humidity, an environment in which afternoon convection was suppressed, keeping cloudiness low and daytime temperatures high. The relative contributions of these factors and possible relations to global warming are discussed. ?? 2009 American Meteorological Society.

  1. Aeromagnetic maps of the Colorado River region including the Kingman, Needles, Salton Sea, and El Centro 1 degree by 2 degrees quadrangles, California, Arizona, and Nevada

    Science.gov (United States)

    Mariano, John; Grauch, V.J.

    1988-01-01

    Aeromagnetic data for the Colorado river region have been compiled as part of the Pacific to Arizona Crustal Experiment (PACE) Project. The data are presented here in a series of six compilations for the Kingman, Needles, Salton Sea, and El Centro 1 degree by 2 degree quadrangles, California, Arizona, and Nevada, at scales of 1:250,000 and 1:750,000. The scales and map areas are identical to those used by Mariano and others (1986) to display the Bouguer and isotatic residual gravity for this region. Data were compiled separately for the Kingman quadrangle, the Needles quadrangle, and an area covering the Salton Sea quadrangle and part of the El Centro quadrangle.

  2. Evaluating Environmental Governance along Cross-Border Electricity Supply Chains with Policy-Informed Life Cycle Assessment: The California-Mexico Energy Exchange.

    Science.gov (United States)

    Bolorinos, Jose; Ajami, Newsha K; Muñoz Meléndez, Gabriela; Jackson, Robert B

    2018-05-01

    This paper presents a "policy-informed" life cycle assessment of a cross-border electricity supply chain that links the impact of each unit process to its governing policy framework. An assessment method is developed and applied to the California-Mexico energy exchange as a unique case study. CO 2 -equivalent emissions impacts, water withdrawals, and air quality impacts associated with California's imports of electricity from Mexican combined-cycle facilities fueled by natural gas from the U.S. Southwest are estimated, and U.S. and Mexican state and federal environmental regulations are examined to assess well-to-wire consistency of energy policies. Results indicate most of the water withdrawn per kWh exported to California occurs in Baja California, most of the air quality impacts accrue in the U.S. Southwest, and emissions of CO 2 -equivalents are more evenly divided between the two regions. California energy policy design addresses generation-phase CO 2 emissions, but not upstream CO 2 -eq emissions of methane during the fuel cycle. Water and air quality impacts are not regulated consistently due to varying U.S. state policies and a lack of stringent federal regulation of unconventional gas development. Considering local impacts and the regulatory context where they occur provides essential qualitative information for functional-unit-based measures of life cycle impact and is necessary for a more complete environmental impact assessment.

  3. Determination of the Anthropogenic Carbon Signal to the Total Change in Dissolved Carbon in the Coastal Upwelling Region Along the Washington-Oregon-California Continental Margin

    Science.gov (United States)

    Feely, R. A.

    2016-02-01

    The continental shelf region off the Washington-Oregon-California coast is seasonally exposed to water with a low aragonite saturation state by coastal upwelling of CO2-rich waters. To date, the spatial and temporal distribution of anthropogenic CO2 (Canthro) contribution to the CO2-rich waters is largely unknown. Here we use an adaptation of the linear regression approach described in Feely et al (2008) along with the GO-SHIP Repeat Hydrography data sets from the northeast Pacific to establish an annually updated relationship between Canthro and potential density. This relationship was then used with the NOAA Ocean Acidification Program west coast cruise data sets from 2007, 2011, 2012 and 2013 to determine the spatial variations of Canthro in the upwelled water. Our results show large spatial differences in Canthro in surface waters along the coast with the lowest surface values (40-45 µmol kg-1) in strong upwelling regions of off northern California and southern Oregon and higher values (50-70 µmol kg-1) to the north and south. Canthro contributes an average of about 70% of the increased amount of dissolved inorganic carbon in the upwelled waters at the surface. In contrast, at 50 m the Canthro contribution is approximately 31% and at 100 m it averages about 16%. The remaining contributions are primarily due to respiration processes in the water that was upwelled and transported to coastal regions or underwent respiration processes that occurred locally during the course of the upwelling season. The uptake of Canthro has caused the aragonite saturation horizon to shoal by approximately 30-50 m since preindustrial period so that the undersaturated waters are well within the regions that affect the biological communities on the continental shelf.

  4. Modeling regional aerosol and aerosol precursor variability over California and its sensitivity to emissions and long-range transport during the 2010 CalNex and CARES campaigns

    Science.gov (United States)

    Fast, J. D.; Allan, J.; Bahreini, R.; Craven, J.; Emmons, L.; Ferrare, R.; Hayes, P. L.; Hodzic, A.; Holloway, J.; Hostetler, C.; Jimenez, J. L.; Jonsson, H.; Liu, S.; Liu, Y.; Metcalf, A.; Middlebrook, A.; Nowak, J.; Pekour, M.; Perring, A.; Russell, L.; Sedlacek, A.; Seinfeld, J.; Setyan, A.; Shilling, J.; Shrivastava, M.; Springston, S.; Song, C.; Subramanian, R.; Taylor, J. W.; Vinoj, V.; Yang, Q.; Zaveri, R. A.; Zhang, Q.

    2014-09-01

    The performance of the Weather Research and Forecasting regional model with chemistry (WRF-Chem) in simulating the spatial and temporal variations in aerosol mass, composition, and size over California is quantified using the extensive meteorological, trace gas, and aerosol measurements collected during the California Nexus of Air Quality and Climate Experiment (CalNex) and the Carbonaceous Aerosol and Radiative Effects Study (CARES) conducted during May and June of 2010. The overall objective of the field campaigns was to obtain data needed to better understand processes that affect both climate and air quality, including emission assessments, transport and chemical aging of aerosols, aerosol radiative effects. Simulations were performed that examined the sensitivity of aerosol concentrations to anthropogenic emissions and to long-range transport of aerosols into the domain obtained from a global model. The configuration of WRF-Chem used in this study is shown to reproduce the overall synoptic conditions, thermally driven circulations, and boundary layer structure observed in region that controls the transport and mixing of trace gases and aerosols. Reducing the default emissions inventory by 50% led to an overall improvement in many simulated trace gases and black carbon aerosol at most sites and along most aircraft flight paths; however, simulated organic aerosol was closer to observed when there were no adjustments to the primary organic aerosol emissions. We found that sulfate was better simulated over northern California whereas nitrate was better simulated over southern California. While the overall spatial and temporal variability of aerosols and their precursors were simulated reasonably well, we show cases where the local transport of some aerosol plumes were either too slow or too fast, which adversely affects the statistics quantifying the differences between observed and simulated quantities. Comparisons with lidar and in situ measurements indicate

  5. Three-Dimensional P-wave Velocity Structure Beneath Long Valley Caldera, California, Using Local-Regional Double-Difference Tomography

    Science.gov (United States)

    Menendez, H. M.; Thurber, C. H.

    2011-12-01

    Eastern California's Long Valley Caldera (LVC) and the Mono-Inyo Crater volcanic systems have been active for the past ~3.6 million years. Long Valley is known to produce very large silicic eruptions, the last of which resulted in the formation of a 17 km by 32 km wide, east-west trending caldera. Relatively recent unrest began between 1978-1980 with five ML ≥ 5.7 non-double-couple (NDC) earthquakes and associated aftershock swarms. Similar shallow seismic swarms have continued south of the resurgent dome and beneath Mammoth Mountain, surrounding sites of increased CO2 gas emissions. Nearly two decades of increased volcanic activity led to the 1997 installation of a temporary three-component array of 69 seismometers. This network, deployed by the Durham University, the USGS, and Duke University, recorded over 4,000 high-frequency events from May to September. A local tomographic inversion of 283 events surrounding Mammoth Mountain yielded a velocity structure with low Vp and Vp/Vs anomalies at 2-3 km bsl beneath the resurgent dome and Casa Diablo hot springs. These anomalies were interpreted to be CO2 reservoirs (Foulger et al., 2003). Several teleseismic and regional tomography studies have also imaged low Vp anomalies beneath the caldera at ~5-15 km depth, interpreted to be the underlying magma reservoir (Dawson et al., 1990; Weiland et al., 1995; Thurber et al., 2009). This study aims to improve the resolution of the LVC regional velocity model by performing tomographic inversions using the local events from 1997 in conjunction with regional events recorded by the Northern California Seismic Network (NCSN) between 1980 and 2010 and available refraction data. Initial tomographic inversions reveal a low velocity zone at ~2 to 6 km depth beneath the caldera. This structure may simply represent the caldera fill. Further iterations and the incorporation of teleseismic data may better resolve the overall shape and size of the underlying magma reservoir.

  6. Densidad de desarrollo alta y baja en Puerto Rico

    Science.gov (United States)

    William A. Gould; Sebastian Martinuzzi; Olga M. Ramos Gonzalez

    2008-01-01

    Este mapa demuestra la distribución de terrenos de alta y baja densidad de desarrollo urbano en Puerto Rico (Martinuzzi et al. 2007). El mapa fue creado mediante el analisis de un mosaico de imagenes de satelite Landsat ETM+ de los años 2000 – 2003. La clasificacion no supervisada ISODATA (“Iterative Self-Organizing Data Analysis Technique”) (ERDAS 2003) fue utilizada...

  7. Using the Terrestrial Observation and Prediction System (TOPS) to Analyze Impacts of Climate Change on Ecosystems within Northern California Climate Regions

    Science.gov (United States)

    Pitts, K.; Little, M.; Loewenstein, M.; Iraci, L. T.; Milesi, C.; Schmidt, C.; Skiles, J. W.

    2011-12-01

    The projected impacts of climate change on Northern California ecosystems using model outputs from the Terrestrial Observation and Prediction System (TOPS) for the period 1950-2099 based on 1km downscaled climate data from the Geophysical Fluid Dynamics Laboratory (GFDL) model are analyzed in this study. The impacts are analyzed for the Special Report Emissions Scenarios (SRES) A1B and A2, both maintaining present levels of urbanization constant and under projected urban expansion. The analysis is in support of the Climate Adaptation Science Investigation at NASA Ames Research Center. A statistical analysis is completed for time series of temperature, precipitation, gross primary productivity (GPP), evapotranspiration, soil runoff, and vapor pressure deficit. Trends produced from this analysis show that increases in maximum and minimum temperatures lead to declines in peak GPP, length of growing seasons, and overall declines in runoff within the watershed. For Northern California, GPP is projected under the A2 scenario to decrease by 18-25% by the 2090 decade as compared to the 2000 decade. These trends indicate a higher risk to crop production and other ecosystem services, as conditions would be less hospitable to vegetation growth. The increase in dried out vegetation would then lead to a higher risk of wildfire and mudslides in the mountainous regions.

  8. A new algorithm for three-dimensional joint inversion of body wave and surface wave data and its application to the Southern California plate boundary region

    Science.gov (United States)

    Fang, Hongjian; Zhang, Haijiang; Yao, Huajian; Allam, Amir; Zigone, Dimitri; Ben-Zion, Yehuda; Thurber, Clifford; van der Hilst, Robert D.

    2016-05-01

    We introduce a new algorithm for joint inversion of body wave and surface wave data to get better 3-D P wave (Vp) and S wave (Vs) velocity models by taking advantage of the complementary strengths of each data set. Our joint inversion algorithm uses a one-step inversion of surface wave traveltime measurements at different periods for 3-D Vs and Vp models without constructing the intermediate phase or group velocity maps. This allows a more straightforward modeling of surface wave traveltime data with the body wave arrival times. We take into consideration the sensitivity of surface wave data with respect to Vp in addition to its large sensitivity to Vs, which means both models are constrained by two different data types. The method is applied to determine 3-D crustal Vp and Vs models using body wave and Rayleigh wave data in the Southern California plate boundary region, which has previously been studied with both double-difference tomography method using body wave arrival times and ambient noise tomography method with Rayleigh and Love wave group velocity dispersion measurements. Our approach creates self-consistent and unique models with no prominent gaps, with Rayleigh wave data resolving shallow and large-scale features and body wave data constraining relatively deeper structures where their ray coverage is good. The velocity model from the joint inversion is consistent with local geological structures and produces better fits to observed seismic waveforms than the current Southern California Earthquake Center (SCEC) model.

  9. Impact of the North American Free Trade Agreement on transportation in the border areas of the United States : with emphasis on the California-Mexico border

    Science.gov (United States)

    1999-08-01

    This report identifies impacts of the North ?American Free Trade Agreement (NAFTA) on transportation in the U.S. border areas. Emphasis is on the California-Baja California border zone. Focus is on the identification of recommendations to the Califor...

  10. California Geological Survey Geologic Map Index

    Data.gov (United States)

    California Natural Resource Agency — All the individual maps from the Geologic Atlas of California and the Regional Geologic map series have been georeferenced for display in a GIS (and viewable online...

  11. Low-Level {beta} and {gamma} Counting in the Region 0-10 Disintegrations Per Minute; Comptage {beta} et {gamma} d'echantillons de faible activite (0 a 10 desintegrations par minute); Izmerenie {beta}- i {gamma}-izlucheniya maloj moshchnosti (0-10 raspadov v minutu); Recuento {beta} y {gamma} de muestras de baja actividad (0 a 10 desintegraciones por minuto)

    Energy Technology Data Exchange (ETDEWEB)

    Manov, George G [Tracerlab Inc. (United States)

    1960-06-15

    Measurements of levels of radioactivity in the region of 0-1.0 disintegrations per minute are becoming increasingly useful in the standardization of radionuclides as well as in other branches of science such as geology and medicine. For example, there is frequent need for low-level counting in the field of biological and tracer applications, particularly, in those cases in which the use of a higher level of radiation would alter the course of the mechanism or process under study. Frequently such measurements must be made under conditions in which the sample possesses an activity of only 1% of the normal, unshielded background radiation. At other times, an additional requirement is imposed because the radionuclide may have a very short half-life. There are three general ways in which the reliability of low-level measurements can be increased: more efficient counters, smaller background corrections and more stable, noise-free electronic systems. In this paper, comparative tests are described of the relative merits of hree different types of guard (anti-coincidence) counters in reducing the background. Measurements were made of: (a) umbrella, (b) annular, and (c) scintillating plastic igloo. The increasing difficulty of obtaining activity-free materials for construction of counters is a matter of some concern. Data are presented for the range of activities of materials available commercially. Stockpiling of such materials, preferably of pre-War II origin is rapidly becoming a necessity. The stability of the electronic system is a prime requisite for low level counting, particularly to avoid the counting of spurious pulses. A system is described in which a slow, measured rate of pulses is fed into the electronics, passed through the amplifier and deducted from the gross output of the register. In general, transistorized circuitry including pre-amplifiers and power supplies are more satisfactory than conventional vacuum tube devices. (author) [French] La mesure des

  12. Studies of geology and hydrology in the Basin and Range province, southwestern United States, for isolation of high-level radioactive waste: characterization of the Sonoran region, California

    International Nuclear Information System (INIS)

    Bedinger, M.S.; Sargent, Kenneth A.; Langer, William H.

    1989-01-01

    The Sonoran region of California lies west of the Colorado River and adjoins the Mojave Desert on the west, Death Valley on the northwest, and the Salton trough on the south. The region is arid with annual precipitation ranging from less than 80 millimeters to as great as 250 millimeters in one mountain range; annual free-surface evaporation is as great as 2,500 millimeters. The characteristic basin and range topography of the region was caused by a mid-Tertiary period of intense crustal extension, accompanied by volcanic eruptions, clastic sedimentation, faulting, and tilting. Potential host media for isolation of high-level radioactive waste include granite and other coarsegrained plutonic rocks, ash-flow tuff, and basalt and basaltic andesite lava flows. Thick sections of the unsaturated zone in basin fill, intrusive, and volcanic rocks appear to have potential as host media. The region is bordered on the west by areas of relatively greater Quaternary faulting, vertical crustal uplift, and seismicity. The region has a few areas of Quaternary volcanic activity. Geothermal heat flows of 2.5 heat-flow units or greater and one earthquake of magnitude 6-7 have been recorded. The region includes topographically closed basins as well as basins that drain to the Colorado River. Dry lakes and playas occupy the closed basins. Ground-water recharge and surface runoff are small because of the small amount of precipitation and great potential evaporation. Natural ground-water discharge is by evaporation in the basin playas and by underflow to the Colorado River. Dissolved-solids concentration of ground water generally is less than 500 milligrams per liter, and much of it is of the sodium bicarbonate type. Ground water is saline in many of the playas, and chloride or sulfate is the predominant anion. Small tonnages of ore have been produced from numerous precious and fewer base-metal deposits. (author)

  13. Atmospheric Wind Relaxations and the Oceanic Response in the California Current Large Marine Ecosystem

    Science.gov (United States)

    Fewings, M. R.; Dorman, C. E.; Washburn, L.; Liu, W.

    2010-12-01

    On the West Coast of North America in summer, episodic relaxation of the upwelling-favorable winds causes warm water to propagate northward from southern to central California, against the prevailing currents [Harms and Winant 1998, Winant et al. 2003, Melton et al. 2009]. Similar wind relaxations are an important characteristic of coastal upwelling ecosystems worldwide. Although these wind relaxations have an important influence on coastal ocean dynamics, no description exists of the regional atmospheric patterns that lead to wind relaxations in southern California, or of the regional ocean response. We use QuikSCAT wind stress, North American Regional Reanalysis atmospheric pressure products, water temperature and velocity from coastal ocean moorings, surface ocean currents from high-frequency radars, and MODIS satellite sea-surface temperature and ocean color images to analyze wind relaxation events and the ocean response. We identify the events based on an empirical index calculated from NDBC buoy winds [Melton et al. 2009]. We describe the regional evolution of the atmosphere from the Gulf of Alaska to Baja California over the few days leading up to wind relaxations, and the coastal ocean temperature, color, and current response off southern and central California. We analyze ~100 wind relaxation events in June-September during the QuikSCAT mission, 1999-2009. Our results indicate south-central California wind relaxations in summer are tied to mid-level atmospheric low-pressure systems that form in the Gulf of Alaska and propagate southeastward over 3-5 days. As the low-pressure systems reach southern California, the atmospheric pressure gradient along the coast weakens, causing the surface wind stress to relax to near zero. The weak wind signal appears first at San Diego and propagates northward. QuikSCAT data indicate the relaxed winds extend over the entire Southern California Bight and up to 200 km offshore of central California. Atmospheric dynamics in

  14. Source apportionment of visual impairment during the California regional PM 10/PM 2.5 air quality study

    Science.gov (United States)

    Chen, Jianjun; Ying, Qi; Kleeman, Michael J.

    2009-12-01

    Gases and particulate matter predictions from the UCD/CIT air quality model were used in a visibility model to predict source contributions to visual impairment in the San Joaquin Valley (SJV), the southern portion of California's Central Valley, during December 2000 and January 2001. Within the SJV, daytime (0800-1700 PST) light extinction was dominated by scattering associated with airborne particles. Measured daytime particle scattering coefficients were compared to predicted values at approximately 40 locations across the SJV after correction for the increased temperature and decreased relative humidity produced by "smart heaters" placed upstream of nephelometers. Mean fractional bias and mean fractional error were -0.22 and 0.65, respectively, indicating reasonable agreement between model predictions and measurements. Particulate water, nitrate, organic matter, and ammonium were the major particulate species contributing to light scattering in the SJV. Daytime light extinction in the SJV averaged between December 25, 2000 and January 7, 2001 was mainly associated with animal ammonia sources (28%), diesel engines (18%), catalyst gasoline engines (9%), other anthropogenic sources (9%), and wood smoke (7%) with initial and boundary conditions accounting for 13%. The source apportionment results from this study apply to wintertime conditions when airborne particulate matter concentrations are typically at their annual maximum. Further study would be required to quantify source contributions to light extinction in other seasons.

  15. Hydrogeologic evaluation and numerical simulation of the Death Valley regional ground-water flow system, Nevada and California

    International Nuclear Information System (INIS)

    D'Agnese, F.A.; Faunt, C.C.; Turner, A.K.; Hill, M.C.

    1997-01-01

    Yucca Mountain is being studied as a potential site for a high-level radioactive waste repository. In cooperation with the U.S. Department of Energy, the U.S. Geological Survey is evaluating the geologic and hydrologic characteristics of the ground-water system. The study area covers approximately 100,000 square kilometers between lat 35 degrees N., long 115 degrees W and lat 38 degrees N., long 118 degrees W and encompasses the Death Valley regional ground-water flow system. Hydrology in the region is a result of both the and climatic conditions and the complex described as dominated by interbasinal flow and may be conceptualized as having two main components: a series of relatively shallow and localized flow paths that are superimposed on deeper regional flow paths. A significant component of the regional ground-water flow is through a thick Paleozoic carbonate rock sequence. Throughout the regional flow system, ground-water flow is probably controlled by extensive and prevalent structural features that result from regional faulting and fracturing. Hydrogeologic investigations over a large and hydrogeologically complex area impose severe demands on data management. This study utilized geographic information systems and geoscientific information systems to develop, store, manipulate, and analyze regional hydrogeologic data sets describing various components of the ground-water flow system

  16. Hydrogeochemical evaluation of conventional and hot dry rock geothermal resource potential in the Clear Lake region, California

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.; Adams, A.I.; Trujillo, P.E.; Counce, D.

    1993-05-01

    Chemistry, stable isotope, and tritium contents of thermal/mineral waters in the Clear Lake region were used to evaluate conventional and hot dry rock (HDR) geothermal potential for electrical generation. Thermal/mineral waters of the Clear Lake region are broadly classified as thermal meteoric and connate types based on chemical and isotopic criteria. Ratios of conservative components such as B/Cl are extremely different among all thermal/mineral waters of the Clear Lake region except for clusters of waters emerging from specific areas such as the Wilbur Springs district and the Agricultural Park area south of Mt. Konocti. In contrast ratios of conservative components in large, homogeneous geothermal reservoirs are constant. Stable isotope values of Clear Lake region waters show a mixing trend between thermal meteoric and connate (generic) end-members. The latter end-member has enriched {delta}D as well as enriched {delta}{sup 18}O, from typical high-temperature geothermal reservoir waters. Tritium data indicate most Clear Lake region waters are mixtures of old and young fluid components. Subsurface equilibration temperature of most thermal/mineral waters of the Clear Lake region is {le}150{degree}C based on chemical geothermometers but it is recognized that Clear Lake region waters are not typical geothermal fluids and that they violate rules of application of many geothermometers. The combined data indicate that no large geothermal reservoir underlies the Clear Lake region and that small localized reservoirs have equilibration temperatures {le}150{degree}C (except for Sulphur Bank mine). HDR technologies are probably the best way to commercially exploit the known high-temperatures existing beneath the Clear Lake region particularly within and near the main Clear Lake volcanic field.

  17. California Environmental Vulnerability Assessment (CEVA) Score, San Joaquin Valley CA, 2013, UC Davis Center for Regional Change

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data set is based on a three year study by the UC Davis Center for Regional Change, in affiliation with the Environmental Justice Project of the John Muir...

  18. Geochemistry of thermal/mineral waters in the Clear Lake region, California, and implications for hot dry rock geothermal development

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.; Adams, A.I.; Trujillo, P.E.; Counce, D.; Mansfield, J.

    1993-02-01

    Thermal/mineral waters of the Clear Lake region are broadly classified as thermal meteoric and connote types based on chemical and isotopic criteria. Ratios of conservative components such as B/Cl are extremely different among all thermal/mineral waters of the Clear Lake region except for clusters of waters emerging from specific areas such as the Wilbur Springs district and the Agricultural Park area south of Mt. Konocti. In contrast, ratios of conservative components in large, homogeneous geothermal reservoirs are constant. Stable isotope values of Clear Lake region waters show a mixing trend between thermal meteoric and connote end-members. The latter end-member has enriched [delta]D as well as enriched d[sup l8]O, very different from typical high-temperature geothermal reservoir waters. Tritium data and modeling of ages indicate most Clear Lake region waters are 500 to > 10,000 yr., although mixing of old and young components is implied by the data. The age of end-member connate water is probably > 10,000 yr. Subsurface equilibration temperature of most thermal/mineral waters of the Clear Lake region is [le] 150[degrees]C based on chemical geothermometers but it is recognized that Clear Lake region waters are not typical geothermal fluids and that they violate rules of application of many geothermometers. The combined data indicate that no large geothermal reservoir underlies the Clear Lake region and that small localized reservoirs have equilibration temperatures [le] 150[degrees]C (except for Sulphur Bank Mine). Hot dry rock technologies are the best way to commercially exploit the known high temperatures existing beneath the Clear Lake region, particularly within the main Clear Lake volcanic field.

  19. Prevalence of shiga toxin producing Escherichia coli, Salmonella enterica, and Listeria monocytogenes at public access watershed sites in a California Central Coast agricultural region.

    Science.gov (United States)

    Cooley, Michael B; Quiñones, Beatriz; Oryang, David; Mandrell, Robert E; Gorski, Lisa

    2014-01-01

    Produce contaminated with enteric pathogens is a major source of foodborne illness in the United States. Lakes, streams, rivers, and ponds were sampled with Moore swabs bi-monthly for over 2 years at 30 locations in the vicinity of a leafy green growing region on the Central California Coast and screened for Shiga toxin producing Escherichia coli (STEC), Salmonella enterica, and Listeria monocytogenes to evaluate the prevalence and persistence of pathogen subtypes. The prevalence of STEC from 1386 samples was 11%; 110 samples (8%) contained E. coli O157:H7 with the highest prevalence occurring close to cattle operations. Non-O157 STEC isolates represented major clinical O-types and 57% contained both shiga toxin types 1 and 2 and intimin. Multiple Locus Variable Number Tandem Repeat Analysis of STEC isolates indicated prevalent strains during the period of study. Notably, Salmonella was present at high levels throughout the sampling region with 65% prevalence in 1405 samples resulting in 996 isolates with slightly lower prevalence in late autumn. There were 2, 8, and 14 sites that were Salmonella-positive over 90, 80, and 70% of the time, respectively. The serotypes identified most often were 6,8:d:-, Typhimurium, and Give. Interestingly, analysis by Pulsed Field Gel Electrophoresis indicated persistence and transport of pulsotypes in the region over several years. In this original study of L. monocytogenes in the region prevalence was 43% of 1405 samples resulting in 635 individual isolates. Over 85% of the isolates belonged to serotype 4b with serotypes 1/2a, 1/2b, 3a, 4d with 4e representing the rest, and there were 12 and 2 sites that were positive over 50 and 80% of the time, respectively. Although surface water is not directly used for irrigation in this region, transport to the produce can occur by other means. This environmental survey assesses initial contamination levels toward an understanding of transport leading to produce recalls or outbreaks.

  20. Galaxias satélites de baja luminosidad /

    OpenAIRE

    Lares, Marcelo

    2009-01-01

    Tesis (Doctor en Astronomía)--Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física, 2009. Se lleva a cabo una caracterización estadística de las poblaciones de galaxias de baja luminosidad asociadas a sistemas de galaxias brillantes y aisladas, pares de galaxias interactuantes, grupos y cúmulos con emisión en rayos X, identificados en el espacio de redshifts. Se determinan estadísticamente las distribuciones de parámetros que describen las propiedades de g...

  1. CARACTERÍSTICAS DE LA CUENCA BAJA DEL RIO SEGUNDO

    OpenAIRE

    Morera Castro, Gerardo

    2011-01-01

    En este documento se representan las características naturales de la Cuenca Baja del río Segundo, especialmente características hidrográficas, climáticas y usos del suelo.   La cuenca ubicada en la Región Central de Costa Rica, tiene todas las dificultades inherentes a los procesos de usos intensivos del suelo, de urbanización e industrialización.  Desde la cuenca alta con procesos de deforestación y uso inadecuado del suelo hasta su cuenca con procesos urbanos e industriales sin contron ni p...

  2. Diseño de un aerogenerador de baja potencia

    OpenAIRE

    Hernández Agriarte, Javier

    2005-01-01

    El objetivo del proyecto es diseñar un aerogenerador de baja potencia, que cubra las necesidades energéticas de una vivienda aislada de la red la cual se encuentra situada en Portbou. Para ello se realiza un estudio energético en el cual se define el tamaño del aerogenerador. Al ser una aplicación doméstica, sin gran demanda de energía se diseña un aerogenerador de 2,5 m de diámetro de palas. La principal característica del aerogenerador objeto de estudio es el alternador de im...

  3. Simulated effects of climate change on the Death Valley regional ground-water flow system, Nevada and California

    International Nuclear Information System (INIS)

    D'Agnese, F.A.; O'Brien, G.M.; Faunt, C.C.; San Juan, C.A.

    1999-01-01

    The US Geological Survey, in cooperation with the US Department of Energy, is evaluating the geologic and hydrologic characteristics of the Death Valley regional flow system as part of the Yucca Mountain Project. As part of the hydrologic investigation, regional, three-dimensional conceptual and numerical ground-water-flow models have been developed to assess the potential effects of past and future climates on the regional flow system. A simulation that is based on climatic conditions 21,000 years ago was evaluated by comparing the simulated results to observation of paleodischarge sites. Following acceptable simulation of a past climate, a possible future ground-water-flow system, with climatic conditions that represent a doubling of atmospheric carbon dioxide, was simulated. The steady-state simulations were based on the present-day, steady-state, regional ground-water-flow model. The finite-difference model consisted of 163 rows, 153 columns, and 3 layers and was simulated using MODFLOWP. Climate changes were implemented in the regional ground-water-flow model by changing the distribution of ground-water recharge. Global-scale, average-annual, simulated precipitation for both past- and future-climate conditions developed elsewhere were resampled to the model-grid resolution. A polynomial function that represents the Maxey-Eakin method for estimating recharge from precipitation was used to develop recharge distributions for simulation

  4. Dilemas diagnósticos y terapéuticos en talla baja

    OpenAIRE

    Ceñal González-Fierro, M.J.

    2009-01-01

    Una separación clara entre una talla normal y una talla baja es difícil de establecer. Se consideran tallas altas las situadas entre + 2 desviaciones estándar (DE) para la edad, sexo y grupo étnico y tallas bajas las que se encuentran por debajo de 2 DE, que corresponde aproximadamente al P3 de las curvas de referencia. Se distinguen dos grupos: talla baja normal, en el que están incluidos los niños con talla baja familiar, con retraso constitucional del crecimiento y desarrollo o con retraso...

  5. Tectonic geomorphology and volcano-tectonic interaction in the eastern boundary of the Southern Cascades (Hat Creek Graben region, California, USA

    Directory of Open Access Journals (Sweden)

    Engielle Mae Raot-raot Paguican

    2016-07-01

    Full Text Available The eastern boundary of the Southern Cascades (Hat Creek Graben region, California, USA, is an extensively faulted volcanic corridor between the Cascade Range and Modoc Plateau. The east-west extending region is in the transition zone between the convergence and subduction of the Gorda Plate underneath the North American Plate; north-south shortening within the Klamath Mountain region; and transcurrent movement in the Walker Lane. We describe the geomorphological and tectonic features, their alignment and distribution, in order to understand the tectonic geomorphology and volcano-tectonic relationships. One outcome of the work is a more refined morpho-structural description that will affect future hazard assessment in the area.A database of volcanic centers and structures was created from interpretations of topographic models generated from satellite images. Volcanic centers in the region were classified by morphological type into cones, sub-cones, shields and massifs. A second classification by height separated the bigger and smaller edifices and revealed an evolutionary trend. Poisson Nearest Neighbor analysis shows that bigger volcanoes are spatially dispersed while smaller ones are clustered. Using volcano centroid locations, about 90 lineaments consisting of at least three centers within 6km of one another were found, revealing that preferential north-northwest directed pathways control the transport of magma from the source to the surface, consistent with the strikes of the major fault systems. Most of the volcano crater openings are perpendicular to the maximum horizontal stress, expected for extensional environments with dominant normal regional faults. These results imply that the extension of the Hat Creek Graben region and impingement of the Walker Lane is accommodated mostly by extensional faults and partly by the intrusions that formed the volcanoes. Early in the history of a volcano or volcano cluster, melt produced at depth in the

  6. Death Valley regional ground-water flow system, Nevada and California -- hydrogeologic framework and transient ground-water flow model

    Science.gov (United States)

    Belcher, Wayne R.

    2004-01-01

    A numerical three-dimensional (3D) transient ground-water flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the ground-water flow system and previous less extensive ground-water flow models were incorporated and reevaluated together with new data to provide greater detail for the complex, digital model. A 3D digital hydrogeologic framework model (HFM) was developed from digital elevation models, geologic maps, borehole information, geologic and hydrogeologic cross sections, and other 3D models to represent the geometry of the hydrogeologic units (HGUs). Structural features, such as faults and fractures, that affect ground-water flow also were added. The HFM represents Precambrian and Paleozoic crystalline and sedimentary rocks, Mesozoic sedimentary rocks, Mesozoic to Cenozoic intrusive rocks, Cenozoic volcanic tuffs and lavas, and late Cenozoic sedimentary deposits of the Death Valley Regional Ground-Water Flow System (DVRFS) region in 27 HGUs. Information from a series of investigations was compiled to conceptualize and quantify hydrologic components of the ground-water flow system within the DVRFS model domain and to provide hydraulic-property and head-observation data used in the calibration of the transient-flow model. These studies reevaluated natural ground-water discharge occurring through evapotranspiration and spring flow; the history of ground-water pumping from 1913 through 1998; ground-water recharge simulated as net infiltration; model boundary inflows and outflows based on regional hydraulic gradients and water budgets of surrounding areas; hydraulic conductivity and its relation to depth; and water levels appropriate for regional simulation of prepumped and pumped conditions within the DVRFS model domain. Simulation results appropriate for the regional extent and scale of the model were

  7. Death Valley regional groundwater flow system, Nevada and California-Hydrogeologic framework and transient groundwater flow model

    Science.gov (United States)

    Belcher, Wayne R.; Sweetkind, Donald S.

    2010-01-01

    A numerical three-dimensional (3D) transient groundwater flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the groundwater flow system and previous less extensive groundwater flow models were incorporated and reevaluated together with new data to provide greater detail for the complex, digital model. A 3D digital hydrogeologic framework model (HFM) was developed from digital elevation models, geologic maps, borehole information, geologic and hydrogeologic cross sections, and other 3D models to represent the geometry of the hydrogeologic units (HGUs). Structural features, such as faults and fractures, that affect groundwater flow also were added. The HFM represents Precambrian and Paleozoic crystalline and sedimentary rocks, Mesozoic sedimentary rocks, Mesozoic to Cenozoic intrusive rocks, Cenozoic volcanic tuffs and lavas, and late Cenozoic sedimentary deposits of the Death Valley regional groundwater flow system (DVRFS) region in 27 HGUs. Information from a series of investigations was compiled to conceptualize and quantify hydrologic components of the groundwater flow system within the DVRFS model domain and to provide hydraulic-property and head-observation data used in the calibration of the transient-flow model. These studies reevaluated natural groundwater discharge occurring through evapotranspiration (ET) and spring flow; the history of groundwater pumping from 1913 through 1998; groundwater recharge simulated as net infiltration; model boundary inflows and outflows based on regional hydraulic gradients and water budgets of surrounding areas; hydraulic conductivity and its relation to depth; and water levels appropriate for regional simulation of prepumped and pumped conditions within the DVRFS model domain. Simulation results appropriate for the regional extent and scale of the model were provided

  8. Regional variations in upper mantle compressional velocities beneath southern California 1. Post-shock temperatures: Their experimental determination, calculation, and implications, 2.. Ph.D. Thesis

    Science.gov (United States)

    Raikes, S. A.

    1978-01-01

    The compressional velocity within the upper mantle beneath Southern California is investigated through observations of the dependence of teleseismic P-delays at all stations of the array on the distance and azimuth to the event. The variation of residuals with azimuth was found to be as large as 1.3 sec at a single station; the delays were stable as a function of time, and no evidence was found for temporal velocity variations related to seismic activity in the area. These delays were used in the construction of models for the upper mantle P-velocity structure to depths of 150 km, both by ray tracing and inversion techniques. The models exhibit considerable lateral heterogeneity including a region of low velocity beneath the Imperial Valley, and regions of increased velocity beneath the Sierra Nevada and much of the Transverse Ranges. The development is described of a technique for the experimental determination of post-shock temperatures, and its application to several metals and silicates shocked to pressures in the range 5 to 30 GPa. The technique utilizes an infra-red radiation detector to determine the brightness temperature of the free surface of the sample after the shock wave has passed through it.

  9. An estimated potentiometric surface of the Death Valley region, Nevada and California, developed using geographic information system and automated interpolation techniques

    International Nuclear Information System (INIS)

    D'Agnese, F.A.; Faunt, C.C.; Turner, A.K.

    1998-01-01

    An estimated potentiometric surface was constructed for the Death Valley region, Nevada and California, from numerous, disparate data sets. The potentiometric surface was required for conceptualization of the ground-water flow system and for construction of a numerical model to aid in the regional characterization for the Yucca Mountain repository. Because accurate, manual extrapolation of potentiometric levels over large distances is difficult, a geographic-information-system method was developed to incorporate available data and apply hydrogeologic rules during contour construction. Altitudes of lakes, springs, and wetlands, interpreted as areas where the potentiometric surface intercepts the land surface, were combined with water levels from well data. Because interpreted ground-water recharge and discharge areas commonly coincide with groundwater basin boundaries, these areas also were used to constrain a gridding algorithm and to appropriately place local maxima and minima in the potentiometric-surface map. The resulting initial potentiometric surface was examined to define areas where the algorithm incorrectly extrapolated the potentiometric surface above the land surface. A map of low-permeability rocks overlaid on the potentiometric surface also indicated areas that required editing based on hydrogeologic reasoning. An interactive editor was used to adjust generated contours to better represent the natural water table conditions, such as large hydraulic gradients and troughs, or ''vees''. The resulting estimated potentiometric-surface map agreed well with previously constructed maps. Potentiometric-surface characteristics including potentiometric-surface mounds and depressions, surface troughs, and large hydraulic gradients were described

  10. Theory of the Sagnac's interferometer of low birefringence and twist fiber; Teoria del interferometro de Sagnac de fibra de baja birrefrigencia y torcida

    Energy Technology Data Exchange (ETDEWEB)

    Estudillo-Ayala, J. M.; Kuzin, E. A.; Ibarra-Escamilla, B. [Instituto Nacional de Astrofisica, Optica y Electronica, Puebla (Mexico); Rojas-Laguna, R. [Universidad de Guanajuato, Guanajuato (Mexico)

    2001-06-01

    The fibre Sagnac interferometer of low birefringence and twist in the lineal region is examined numerically, a method is shown to measure the birefringence in the fibers and rotation of the axes inside of the interferometer fibre loop. [Spanish] El interferometro de Sagnac de fibra de baja birrefrigencia y torcida en la region lineal es numericamente examinado, se muestra un metodo para medir la birrefrigencia en las fibras y rotacion de los ejes dentro de la fibra del lazo del interferometro.

  11. Accelerated Educational Change; The Annual Western Regional Conference on Testing Problems (15th, San Francisco, California, May 6, 1966).

    Science.gov (United States)

    Educational Testing Service, Princeton, NJ.

    The 1966 meeting of the Western Regional Conference on Testing Problems dealt with accelerated educational change. The following speeches were presented: (1) "Access to Higher Education: Implications for Future Planning" by Richard Pearson; (2) "The Differentiated Youth: A Challenge to Traditional Institutions" by Joseph D. Lohman; (3) "Teaching…

  12. Antimony in the Contaminated Site of El Triunfo, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Marmolejo-Rodríguez A. J.

    2013-04-01

    Full Text Available Antimony has properties similar to arsenic with some of its compounds toxic to humans. Therefore it is necessary to control the wastes accumulated by anthropogenic activities, such as mining, where it is in tailings to be released to the environment. According to the Environment Protection Agency, the maximum value in sediments is 11.2 mg Sb kg–1 and the Earth’s crust average is 0.2 mg Sb kg–1. In this semiarid area, the drainage basin El Carrizal is impacted with wastes of an abandoned gold mine at the Mining District El Triunfo (MD – ET which have tailings with 17,600 mg kg–1 of antimony. In the main dry river (arroyo, the Sb content is between 0.6 and 122 mg kg–1. This element is transported from the source throughout the fluvial basin to discharge into the Pacific Ocean. In the arroyo mouth we collected one sedimentary core and the sediment from dunes (28.6 – 45.7 and 6.43 – 7.74 mg Sb kg–1. This research concluded the antimony is enriched in this semiarid system, with Normalized Enrichment Factors severely enriched mainly in arroyo sediments close to the MD-ET

  13. Subcontratación en microempresas y pequeñas empresas de Baja California

    Directory of Open Access Journals (Sweden)

    Natanael Ramírez Angulo

    2004-01-01

    Full Text Available Este artículo demuestra que la subcontratación es un elemento fundamental para incrementar la competitividad de las microempresas y pequeñas empresas cuando favorece dos condiciones: 1 la generación de mayor valor agregado en sus productos, y 2 la capitalización de sus ganancias en un mayor nivel de inversión (subcontratación activa. Asimismo, aplicando un ejercicio de teoría de juegos, se discute un modelo conceptual sobre el proceso mediante el cual los beneficios se transforman en ingresos a través de una relación de subcontratación.

  14. Coastal submarine hydrothermal activity off northern Baja California: 2. Evolutionary history and isotope geochemistry

    Science.gov (United States)

    Vidal, Victor M. V.; Vidal, Francisco V.; Isaacs, John D.

    1981-10-01

    A geochemical model of the Punta Banda submarine hydrothermal system (PBSHS) and Ensenada quadrangle subaerial hot springs is developed using 18O/16O, D/H, 34S/32S, 3H, water and gas chemistry. The PBSHS water is a primary high temperature, acid, reducing fluid of old seawater origin which has been titrated by cold, alkaline groundwater of meteoric origin. The final exiting solutions represent a 1 : 1 mixture of the two primary mixing components. In contrast, the subaerial hot spring waters are of unmixed meteoric origin. The subaerial hot spring gas is predominantly atmospheric N2, while the PBSHS contains large amounts of CH4 and N2 derived from trapped marine sediments of Cretaceous age; δS34 values of sampled hydrothermal waters are similar to Cretaceous marine sulfate values and suggest that the waters contacted Cretaceous marine sedimentary strata. The presence of the Alisitos and Rosario marine sedimentary formations of Cretaceous age within the Ensenada-Punta Banda quadrangle renders support to the above hypothesis. The data also demonstrate that pyrite mineralization and deposition in submarine hydrothermal environments result from the complexing of ferrous iron with elemental sulfur and sulfide and that submarine hydrothermal activity acts as a major source of silica, Ca2+, and trace metals and as a major sink for seawater Mg2+ and SO42-.

  15. Bimodal distribution of risk for childhood obesity in urban Baja California, Mexico.

    Science.gov (United States)

    Wojcicki, Janet M; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B

    2012-08-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4-6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifestyle practices. Multivariate logistic models were used to assess risk factors for obesity (having a body mass index [BMI] ≥95th percentile) and abdominal obesity (a WC >90th percentile) using Stata 11.0. Five hundred and ninety students were enrolled; 43.7% were overweight or obese, and 24.3% were obese and 20.2% had abdominal obesity. Independent risk factors for obesity included watching TV in English (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.06-2.41) and perceived child food insecurity (OR 1.57, 95% CI 1.05-2.36). Decreased risk for obesity was associated with female sex (OR 0.64, 95% CI 0.43-0.96), as was regular multivitamin use (OR 0.63, 95% CI 0.42-0.94). Risk obesity was also decreased with increased taco consumption (≥1×/week; OR 0.64, 95% CI 0.43-0.96). Independent risk factors for abdominal obesity included playing video games ≥1×/week (OR 1.18, 95% CI 1.11-2.96) and older age group (10-11 years, OR 2.47, 95% CI 1.29-4.73 and ≥12 years, OR 2.21, 95% CI 1.09-4.49). Increased consumption of tacos was also associated with decreased risk for abdominal obesity (≥1×/week; OR 0.56, 95% CI 0.40-1.00). We found a bimodal distribution for risk of obesity and abdominal obesity in school aged children on the Mexican border with the United States. Increased risk for obesity and abdominal obesity were associated with factors indicative of lower and higher SES including watching TV in English, increased video game playing and perceived food insecurity. Increased consumption of tacos (≥1×/week) was associated with decreased risk, possibly suggesting an association with children from middle income families. Regular multivitamin use was protective and future studies may focus on micronutrient supplementation as a means to prevent obesity in children or further investigate factors associated with vitamin use. Additionally, future studies need to examine the processes of acculturation on both sides of the US-Mexican border that contribute to increased risk for obesity in children in relation to SES.

  16. Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Velasquez, Michele G; Laniado-Laborin, Rafael; Rodwell, Timothy C; Cerecer, Paris; Lozada, Remedios; Cuevas-Mota, Jazmine; Burgos, Jose Luis; Garfein, Richard S

    2012-07-01

    To assess the prevalence of prior tuberculin skin testing (TST) among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR) = 13.38; 95% confidence interval (CI) = 7.37-24.33] and injection drug use (OR = 1.99; 95% CI = 1.27- 3.11). Positive results on serologic tests for M. tuberculosis infection (57%) and HIV (4.2%) were not associated with a prior TST. A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings.

  17. The Relationship between Mollusks and Oxygen Concentrations in Todos Santos Bay, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    J. Gabriel Kuk-Dzul

    2016-01-01

    Full Text Available This study describes the relationship between mollusks, physicochemical properties of seawater, and sediments under natural conditions of low impact. Thirty-nine stations were sampled in October 1994 using a Van Veen grab (0.1 m−2. Temperature, salinity, and dissolved oxygen (DO concentrations of bottom water were obtained with a CTD. Organic matter content and sediment grain analysis were determined. A total of 836 mollusks were collected. Gastropoda was the most abundant (52% and diverse class with 27 genera, followed by Bivalvia with eight genera and Scaphopoda with only one genus. According to CCA analysis, dominant mollusks were significantly related with high DO concentrations. Donax, Natica, Acteocina, Bulla, Anachis, Odostomia, and Crucibulum can be classified as sensitive genera because they were found mainly in high oxygen concentrations (3.1–5.6 mL L−1; on the other hand, Cardiomya, Nuculana, Laevicardium, Chione, Truncatella, and Dentalium can be classified as tolerant genera (1.0–5.6 mL L−1. Todos Santos Bay hosts a diverse malacological fauna (36 genera; our results show that the dominant genera were mainly related to high dissolved oxygen concentrations. Mollusks can be a useful tool in environmental monitoring programs related with oxygen depletion in coastal areas.

  18. Subsidence monitoring with geotechnical instruments in the Mexicali Valley, Baja California, Mexico

    Science.gov (United States)

    Glowacka, E.; Sarychikhina, O.; Márquez Ramírez, V. H.; Robles, B.; Nava, F. A.; Farfán, F.; García Arthur, M. A.

    2015-11-01

    The Mexicali Valley (northwestern Mexico), situated in the southern part of the San Andreas fault system, is an area with high tectonic deformation, recent volcanism, and active seismicity. Since 1973, fluid extraction, from the 1500-3000 m depth range, at the Cerro Prieto Geothermal Field (CPGF), has influenced deformation in the Mexicali Valley area, accelerating the subsidence and causing slip along the traces of tectonic faults that limit the subsidence area. Detailed field mapping done since 1989 (González et al., 1998; Glowacka et al., 2005; Suárez-Vidal et al., 2008) in the vicinity of the CPGF shows that many subsidence induced fractures, fissures, collapse features, small grabens, and fresh scarps are related to the known tectonic faults. Subsidence and fault rupture are causing damage to infrastructure, such as roads, railroad tracks, irrigation channels, and agricultural fields. Since 1996, geotechnical instruments installed by CICESE (Centro de Investigación Ciéntifica y de Educación Superior de Ensenada, B.C.) have operated in the Mexicali Valley, for continuous recording of deformation phenomena. Instruments are installed over or very close to the affected faults. To date, the network includes four crackmeters and eight tiltmeters; all instruments have sampling intervals in the 1 to 20 min range. Instrumental records typically show continuous creep, episodic slip events related mainly to the subsidence process, and coseismic slip discontinuities (Glowacka et al., 1999, 2005, 2010; Sarychikhina et al., 2015). The area has also been monitored by levelling surveys every few years and, since the 1990's by studies based on DInSAR data (Carnec and Fabriol, 1999; Hansen, 2001; Sarychikhina et al., 2011). In this work we use data from levelling, DInSAR, and geotechnical instruments records to compare the subsidence caused by anthropogenic activity and/or seismicity with slip recorded by geotechnical instruments, in an attempt to obtain more information about the process of fault slip associated with subsidence.

  19. Subsidence monitoring with geotechnical instruments in the Mexicali Valley, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    E. Glowacka

    2015-11-01

    Full Text Available The Mexicali Valley (northwestern Mexico, situated in the southern part of the San Andreas fault system, is an area with high tectonic deformation, recent volcanism, and active seismicity. Since 1973, fluid extraction, from the 1500–3000 m depth range, at the Cerro Prieto Geothermal Field (CPGF, has influenced deformation in the Mexicali Valley area, accelerating the subsidence and causing slip along the traces of tectonic faults that limit the subsidence area. Detailed field mapping done since 1989 (González et al., 1998; Glowacka et al., 2005; Suárez-Vidal et al., 2008 in the vicinity of the CPGF shows that many subsidence induced fractures, fissures, collapse features, small grabens, and fresh scarps are related to the known tectonic faults. Subsidence and fault rupture are causing damage to infrastructure, such as roads, railroad tracks, irrigation channels, and agricultural fields. Since 1996, geotechnical instruments installed by CICESE (Centro de Investigación Ciéntifica y de Educación Superior de Ensenada, B.C. have operated in the Mexicali Valley, for continuous recording of deformation phenomena. Instruments are installed over or very close to the affected faults. To date, the network includes four crackmeters and eight tiltmeters; all instruments have sampling intervals in the 1 to 20 min range. Instrumental records typically show continuous creep, episodic slip events related mainly to the subsidence process, and coseismic slip discontinuities (Glowacka et al., 1999, 2005, 2010; Sarychikhina et al., 2015. The area has also been monitored by levelling surveys every few years and, since the 1990's by studies based on DInSAR data (Carnec and Fabriol, 1999; Hansen, 2001; Sarychikhina et al., 2011. In this work we use data from levelling, DInSAR, and geotechnical instruments records to compare the subsidence caused by anthropogenic activity and/or seismicity with slip recorded by geotechnical instruments, in an attempt to obtain more information about the process of fault slip associated with subsidence.

  20. Shallow Miocene basaltic magma reservoirs in the Bahia de Los Angeles basin, Baja California, Mexico

    Science.gov (United States)

    Delgado-Argote, Luis A.; García-Abdeslem, Juan

    1999-01-01

    The basement in the Bahía de Los Angeles basin consists of Paleozoic metamorphic rocks and Cretaceous granitoids. The Neogene stratigraphy overlying the basement is formed, from the base to the top, by andesitic lava flows and plugs, sandstone and conglomeratic horizons, and Miocene pyroclastic flow units and basaltic flows. Basaltic dikes also intrude the whole section. To further define its structure, a detailed gravimetric survey was conducted across the basin about 1 km north of the Sierra Las Flores. In spite of the rough and lineal topography along the foothills of the Sierra La Libertad, we found no evidence for large-scale faulting. Gravity data indicates that the basin has a maximum depth of 120 m in the Valle Las Tinajas and averages 75 m along the gravimetric profile. High density bodies below the northern part of the Sierra Las Flores and Valle Las Tinajas are interpreted to be part of basaltic dikes. The intrusive body located north of the Sierra Las Flores is 2.5 km wide and its top is about 500 m deep. The lava flows of the top of the Sierra Las Flores, together with the distribution of basaltic activity north of this sierra, suggests that this intrusive body continues for 20 km along a NNW-trending strike. Between the sierras Las Flores and Las Animas, a 0.5-km-wide, 300-m-thick intrusive body is interpreted at a depth of about 100 m. This dike could be part of the basaltic activity of the Cerro Las Tinajas and the small mounds along the foothills of western Sierra Las Animas. The observed local normal faulting in the basin is inferred to be mostly associated with the emplacement of the shallow magma reservoirs below Las Flores and Las Tinajas.

  1. Validation of the ISAAC Standardized Questionnaire Used by Schoolchildren from Mexicali, Baja California, Mexico

    OpenAIRE

    Gorozave-Car, Karla; Barraza-Villarreal, Albino; Escamilla-Núñez, Consuelo; Hernandez-Cadena, Leticia; Sanín-Aguirre, Luz Helena; Cortez-Lugo, Marlene; Blanco-Muñoz, J.; Riojas-Rodríguez, Horacio; Moreno-Macias, Hortensia; Romieu, Isabelle

    2013-01-01

    Background. In Mexico, several studies have been conducted under the ISAAC methodology; nevertheless, no validation studies of the ISAAC questionnaire based on objective clinical testing in our country have been published. Aims of the Study. To validate the ISAAC questionnaire, used in a study of prevalence of allergic diseases, based on medical, respiratory, and allergic evaluations of schoolchildren being 11 to 16 years old in Mexicali, Mexico. Material and Methods. We conducted a cross-sec...

  2. Water management analysis of the city of Tijuana, Baja California: Critical factors and challenges

    Directory of Open Access Journals (Sweden)

    Karina Navarro–Chaparro

    2015-12-01

    Full Text Available This article analyzes water management issues in the urban area of Tijuana for the period from 1991 to 2009. A comprehensive systematic management system was used as a theoretical framework. For the methodological framework, robust databases were compiled through documentary research, semi–structured interviews were conducted, and Geographical Information Systems (GIS were used to visualize the spatial distribution of water use. The results reveal that water resource management is conducted under a linear process that does not consider a broad assessment of social elements in water anagement. The research results show also inequality in the spatial distribution of water services, and little reuse of treated wastewater and the need for long–term planning to secure water supply and consumption after 2020.

  3. Air quality and its integration within urban planning: Mexicali, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Elva Alicia Corona–Zambrano

    2009-07-01

    Full Text Available As a result of world wide urbanization and industrialization, urban air pollution shows a growing trend directly proportional to increasing demands on energy for domestic and industrial activities. From this point of view, cities along with their urban, functional and morphological structure are not being planned with pollution prevention or minimum environmental impacts in mind. This work has two purposes: first, it sets an assessment of air quality in Mexicali by analyzing O3, CO, SO2, NO2 and PM10 emissions in relation to urban structure. And second, the assessment of already implemented urban strategies aimed to minimize environmental impacts. This work also presents a scheme that incorporates air quality issues into town planning and urban management.

  4. Bimodal Distribution of Risk for Childhood Obesity in Urban Baja California, Mexico

    OpenAIRE

    Wojcicki, Janet M.; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B.

    2012-01-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4–6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifest...

  5. Proceedings: third symposium on the Cerro Prieto geothermal field, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    These proceedings include both English and Spanish versions of each paper presented at the symposium. Illustrations and tables, which have been placed between the two versions, include captions in both languages. Forty-one papers are included. Five papers were indexed for EDB previously. Separate abstracts were prepared for thirty-three papers and three were listed by title.

  6. Mortality trends and risk of dying from colorectal cancer in the seven socioeconomic regions of Mexico, 2000-2012

    Directory of Open Access Journals (Sweden)

    J.J. Sánchez-Barriga

    2017-07-01

    Full Text Available Background: In Mexico, there has been an upward trend in mortality rates from colorectal cancer (CRC over the past three decades. This tumor is ranked among the ten most prevalent causes of morbidity from malignancies in Mexico. Aims: To determine the mortality trends by socioeconomic region and by state, and to establish the relative risk between both educational level and socioeconomic region with mortality from CRC within the time frame of 2000-2012. Materials and methods: Records of mortality associated with colorectal cancer were obtained. Rates of mortality by state and by socioeconomic region were calculated, along with the strength of association (obtained through the Poisson regression between both socioeconomic region and educational level and the mortality from CRC. Results: A total of 45,487 individuals died from CRC in Mexico from 2000 to 2012. Age-adjusted mortality rates per 100,000 inhabitants increased from 3.9 to 4.8. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Individuals with no school or incomplete elementary school had a higher risk of dying from this cancer (RR of 3.57, 95% CI: 3.46-3.68. Region 7 had the strongest association with mortality from CRC (Mexico City: RR was 2.84, 95% CI: 2.39-3.37 [2000] and 3.32, 95% CI: 2.89-3.82 [2012]. Conclusions: In Mexico, the age-adjusted mortality rates per 100,000 inhabitants that died from CRC increased from 3.9 to 4.8 in the study period, using the world population age distribution as the standard. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Mexico City, which was socioeconomic region 7, had the strongest association with mortality from CRC. Resumen: Introducción: En México ha habido una tendencia al alza en las tasas de mortalidad por cáncer colorrectal (CCR en las últimas 3 décadas. Esta neoplasia está clasificada dentro de las 10 causas más frecuentes de morbilidad por neoplasias malignas

  7. Assessment of regional change in nitrate concentrations in groundwater in the Central Valley, California, USA, 1950s-2000s

    Science.gov (United States)

    Burow, Karen R.; Jurgens, Bryant C.; Belitz, Kenneth; Dubrovsky, Neil M.

    2013-01-01

    A regional assessment of multi-decadal changes in nitrate concentrations was done using historical data and a spatially stratified non-biased approach. Data were stratified into physiographic subregions on the basis of geomorphology and soils data to represent zones of historical recharge and discharge patterns in the basin. Data were also stratified by depth to represent a shallow zone generally representing domestic drinking-water supplies and a deep zone generally representing public drinking-water supplies. These stratifications were designed to characterize the regional extent of groundwater with common redox and age characteristics, two factors expected to influence changes in nitrate concentrations over time. Overall, increasing trends in nitrate concentrations and the proportion of nitrate concentrations above 5 mg/L were observed in the east fans subregion of the Central Valley. Whereas the west fans subregion has elevated nitrate concentrations, temporal trends were not detected, likely due to the heterogeneous nature of the water quality in this area and geologic sources of nitrate, combined with sparse and uneven data coverage. Generally low nitrate concentrations in the basin subregion are consistent with reduced geochemical conditions resulting from low permeability soils and higher organic content, reflecting the distal portions of alluvial fans and historical groundwater discharge areas. Very small increases in the shallow aquifer in the basin subregion may reflect downgradient movement of high nitrate groundwater from adjacent areas or overlying intensive agricultural inputs. Because of the general lack of regionally extensive long-term monitoring networks, the results from this study highlight the importance of placing studies of trends in water quality into regional context. Earlier work concluded that nitrate concentrations were steadily increasing over time in the eastern San Joaquin Valley, but clearly those trends do not apply to other

  8. A legacy of change: The lower Colorado River, Arizona-California-Nevada, USA, and Sonora-Baja California Norte, Mexico

    Science.gov (United States)

    Mueller, G.A.; Marsh, P.C.; Minckley, W.L.

    2005-01-01

    The lower Colorado is among the most regulated rivers in the world. It ranks as the fifth largest river in volume in the coterminous United States, but its flow is fully allocated and no longer reaches the sea. Lower basin reservoirs flood nearly one third of the river channel and store 2 years of annual flow. Diverted water irrigates 1.5 million ha of cropland and provides water for industry and domestic use by 22 million people in the southwestern United States and northern Mexico. The native fish community of the lower Colorado River was among the most unique in the world, and the main stem was home to nine freshwater species, all of which were endemic to the basin. Today, five are extirpated, seven are federally endangered, and three are being reintroduced through stocking. Decline of the native fauna is attributed to predation by nonnative fishes and physical habitat degradation. Nearly 80 alien species have been introduced, and more than 20 now are common. These nonnative species thrived in modified habitats, where they largely eliminated the native kinds. As a result, the lower Colorado River has the dubious distinction of being among the few major rivers of the world with an entirely introduced fish fauna. ?? 2005 by the American Fisheries Society.

  9. Contaminación y control de las quemas agrícolas en Imperial, California, y Mexicali, Baja California

    Directory of Open Access Journals (Sweden)

    Margarito Quintero Núñez

    2008-01-01

    Full Text Available La quema de residuos agrícolas en los valles de Mexicali e Imperial, separados por una línea divisoria, constituye una fuente importante de emisión de contaminantes al aire, de compuestos como el metano (CH4, monóxido de carbono (CO, bióxido de nitrógeno (NO2, hidrocarburos (NMHC y partículas menores a 10 micras (PM10. Para abordar el problema de los humos agrícolas se debe considerar la cuenca atmosférica común, formada por ambos valles, que comparten un clima extremoso cálido y seco, con menos de 80 mm anuales de lluvia, y basan su economía en la agricultura, y el de Mexicali además en la industria manufacturera y otras actividades. En Mexicali, lo que se quema es sobre todo residuos de trigo y en menor proporción de cebada, cártamo y maíz. Los daños a la salud ocasionados por las emisiones de PM10 son significativos en ambos valles

  10. Documentation of the Santa Clara Valley regional ground-water/surface-water flow model, Santa Clara Valley, California

    Science.gov (United States)

    Hanson, R.T.; Li, Zhen; Faunt, C.C.

    2004-01-01

    The Santa Clara Valley is a long, narrow trough extending about 35 miles southeast from the southern end of San Francisco Bay where the regional alluvial-aquifer system has been a major source of water. Intensive agricultural and urban development throughout the 20th century and related ground-water development resulted in ground-water-level declines of more than 200 feet and land subsidence of as much as 12.7 feet between the early 1900s and the mid-1960s. Since the 1960s, Santa Clara Valley Water District has imported surface water to meet growing demands and reduce dependence on ground-water supplies. This importation of water has resulted in a sustained recovery of the ground-water flow system. To help support effective management of the ground-water resources, a regional ground-water/surface-water flow model was developed. This model simulates the flow of ground water and surface water, changes in ground-water storage, and related effects such as land subsidence. A numerical ground-water/surface-water flow model of the Santa Clara Valley subbasin of the Santa Clara Valley was developed as part of a cooperative investigation with the Santa Clara Valley Water District. The model better defines the geohydrologic framework of the regional flow system and better delineates the supply and demand components that affect the inflows to and outflows from the regional ground-water flow system. Development of the model includes revisions to the previous ground-water flow model that upgraded the temporal and spatial discretization, added source-specific inflows and outflows, simulated additional flow features such as land subsidence and multi-aquifer wellbore flow, and extended the period of simulation through September 1999. The transient-state model was calibrated to historical surface-water and ground-water data for the period 197099 and to historical subsidence for the period 198399. The regional ground-water flow system consists of multiple aquifers that are grouped

  11. Impacts of using an ensemble Kalman filter on air quality simulations along the California-Mexico border region during Cal-Mex 2010 field campaign.

    Science.gov (United States)

    Bei, Naifang; Li, Guohui; Meng, Zhiyong; Weng, Yonghui; Zavala, Miguel; Molina, L T

    2014-11-15

    The purpose of this study is to investigate the impact of using an ensemble Kalman filter (EnKF) on air quality simulations in the California-Mexico border region on two days (May 30 and June 04, 2010) during Cal-Mex 2010. The uncertainties in ozone (O3) and aerosol simulations in the border area due to the meteorological initial uncertainties were examined through ensemble simulations. The ensemble spread of surface O3 averaged over the coastal region was less than 10ppb. The spreads in the nitrate and ammonium aerosols are substantial on both days, mostly caused by the large uncertainties in the surface temperature and humidity simulations. In general, the forecast initialized with the EnKF analysis (EnKF) improved the simulation of meteorological fields to some degree in the border region compared to the reference forecast initialized with NCEP analysis data (FCST) and the simulation with observation nudging (FDDA), which in turn leading to reasonable air quality simulations. The simulated surface O3 distributions by EnKF were consistently better than FCST and FDDA on both days. EnKF usually produced more reasonable simulations of nitrate and ammonium aerosols compared to the observations, but still have difficulties in improving the simulations of organic and sulfate aerosols. However, discrepancies between the EnKF simulations and the measurements were still considerably large, particularly for sulfate and organic aerosols, indicating that there are still ample rooms for improvement in the present data assimilation and/or the modeling systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. A basin-scale approach for assessing water resources in a semiarid environment: San Diego region, California and Mexico

    Directory of Open Access Journals (Sweden)

    L. E. Flint

    2012-10-01

    Full Text Available Many basins throughout the world have sparse hydrologic and geologic data, but have increasing demands for water and a commensurate need for integrated understanding of surface and groundwater resources. This paper demonstrates a methodology for using a distributed parameter water-balance model, gaged surface-water flow, and a reconnaissance-level groundwater flow model to develop a first-order water balance. Flow amounts are rounded to the nearest 5 million cubic meters per year.

    The San Diego River basin is 1 of 5 major drainage basins that drain to the San Diego coastal plain, the source of public water supply for the San Diego area. The distributed parameter water-balance model (Basin Characterization Model was run at a monthly timestep for 1940–2009 to determine a median annual total water inflow of 120 million cubic meters per year for the San Diego region. The model was also run specifically for the San Diego River basin for 1982–2009 to provide constraints to model calibration and to evaluate the proportion of inflow that becomes groundwater discharge, resulting in a median annual total water inflow of 50 million cubic meters per year. On the basis of flow records for the San Diego River at Fashion Valley (US Geological Survey gaging station 11023000, when corrected for upper basin reservoir storage and imported water, the total is 30 million cubic meters per year. The difference between these two flow quantities defines the annual groundwater outflow from the San Diego River basin at 20 million cubic meters per year. These three flow components constitute a first-order water budget estimate for the San Diego River basin. The ratio of surface-water outflow and groundwater outflow to total water inflow are 0.6 and 0.4, respectively. Using total water inflow determined using the Basin Characterization Model for the entire San Diego region and the 0.4 partitioning factor, groundwater outflow from the San Diego region, through

  13. Using CAM3 and the Alkenone Method to Understand how Pliocene SST's Affect California and Other Climates Adjacent to Upwelling Regions

    Science.gov (United States)

    Searles, Z. A.; Otto-Bliesner, B. L.; Rosenbloom, N. A.; Dekens, P. S.

    2008-12-01

    The Intergovernmental Panel on Climate Change fourth assessment report established with 90% confidence that anthropogenic climate change will result in a warmer world. In order to more fully understand possible future climate, past analogues of warm periods should be analyzed. The early Pliocene is an appropriate analogue because the continental configuration was similar to today and CO2 levels were comparable to present (~100ppm higher than pre-anthropogenic levels). This project has two objectives: 1.To test the atmospheric sensitivity to USGS PRISM2 dataset revised to better approximate proxy data indicating warmer SST's in upwelling regions and 2. To provide early-Pliocene (2.7- 3.5 Ma) SST estimates for ODP site 1018 on the California Margin (36°59.4'N, 123°16.5'W) using the UK'37 SST proxy. Recent UK'37 proxy data reveals that PRISM2 underestimates SST's in Pacific and Atlantic coastal upwelling regions. The sensitivity of the atmosphere to significantly warmer SST's in upwelling regions was tested using the National Center for Atmospheric Research (NCAR) Community Atmospheric Model, version 3 (CAM3). Initial conditions were supplied by the USGS PRISM2 project and include Pliocene SST's, vegetation cover, sea level height, topography, marine and continental ice extent. Pliocene SST's along the Californian, Peruvian, North African and South African margin were modified to reflect proxy observations from 4 sites. The lack of observational coverage (1 data point per region) required interpolation of the areal extent of the SST warming anomaly indicated by the proxies. Experiment results show increased cumulative precipitation and humidity in regions where the original PRISM2 predicted drying. The predicted North American increase in precipitation is in better agreement with geologic proxies indicating wetter conditions. Warmer SST's also causes weaker wind velocities along the North American, Peruvian, and North African margins, and stronger winds along the

  14. A paleomagnetic investigation of vertical-axis rotations in coastal Sonora, Mexico: Evidence for distributed transtensional deformation during the Proto-Gulf shift from a subduction-dominated to transform-dominated plate boundary in the Gulf of California

    Science.gov (United States)

    Herman, Scott William

    The history of late Miocene (Proto-Gulf) deformation on the Sonoran margin of the Gulf of California is key to understanding how Baja California was captured by the Pacific plate and how strain was partitioned during the Proto-Gulf period (12.5-6 Ma). The Sierra el Aguaje and Sierra Tinajas del Carmen are located in southwestern coastal Sonora, Mexico, and represent the eastern rifted margin of the central Gulf of California. The ranges are composed of volcanic units and their corresponding volcaniclastic units which are the result of persistent magmatic activity between 20 and 8.8 Ma, including three packages of basalt and andesite that make excellent paleomagnetic recorders. Based on cross cutting relations and geochronologic data for pre-, syn-, and post-tectonic volcanic units, most of the faulting and tilting in the Sierra El Aguaje is bracketed between 11.9 and 9.0 Ma, thus falling entirely within Proto-Gulf time. A paleomagnetic investigation into possible vertical axis rotations in the Sierra el Aguaje has uncovered evidence of clockwise rotations between ~13º and ~105º with possible translations. These results are consistent with existing field relations, which suggest the presence of large (>45°) vertical axis rotations in this region. This evidence includes: a) abrupt changes in the strike of tilted strata in different parts of the range, including large domains characterized by E-W strikes b) ubiquitous NE-SW striking faults with left lateral-normal oblique slip, that terminate against major NW-trending right lateral faults, and c) obliquity between the general strike of tilted strata and the strike of faults. These rotations occurred after 12 Ma and largely prior to 9 Ma, thus falling into the Proto-Gulf period. Such large-scale rotations lend credence to the theory that the area inboard of Baja California was experiencing transtension during the Proto-Gulf period, rather than the pure extension that would be the result of strain partitioning

  15. Preliminary estimates of spatially distributed net infiltration and recharge for the Death Valley region, Nevada-California

    International Nuclear Information System (INIS)

    Hevesi, J.A.; Flint, A.L.; Flint, L.E.

    2002-01-01

    A three-dimensional ground-water flow model has been developed to evaluate the Death Valley regional flow system, which includes ground water beneath the Nevada Test Site. Estimates of spatially distributed net infiltration and recharge are needed to define upper boundary conditions. This study presents a preliminary application of a conceptual and numerical model of net infiltration. The model was developed in studies at Yucca Mountain, Nevada, which is located in the approximate center of the Death Valley ground-water flow system. The conceptual model describes the effects of precipitation, runoff, evapotranspiration, and redistribution of water in the shallow unsaturated zone on predicted rates of net infiltration; precipitation and soil depth are the two most significant variables. The conceptual model was tested using a preliminary numerical model based on energy- and water-balance calculations. Daily precipitation for 1980 through 1995, averaging 202 millimeters per year over the 39,556 square kilometers area of the ground-water flow model, was input to the numerical model to simulate net infiltration ranging from zero for a soil thickness greater than 6 meters to over 350 millimeters per year for thin soils at high elevations in the Spring Mountains overlying permeable bedrock. Estimated average net infiltration over the entire ground-water flow model domain is 7.8 millimeters per year. To evaluate the application of the net-infiltration model developed on a local scale at Yucca Mountain, to net-infiltration estimates representing the magnitude and distribution of recharge on a regional scale, the net-infiltration results were compared with recharge estimates obtained using empirical methods. Comparison of model results with previous estimates of basinwide recharge suggests that the net-infiltration estimates obtained using this model may overestimate recharge because of uncertainty in modeled precipitation, bedrock permeability, and soil properties for

  16. Presentations from the Workshop On SABER: South Arc Beam Experimental Region, March 15-16, 2006, Menlo Park, California

    International Nuclear Information System (INIS)

    Noble, R.

    2006-01-01

    SABER (the South Arc Beam Experimental Region) is a proposed facility for experiments with 30 GeV electron and positron beams from the SLAC linac. The combination of a short bunch length (s z ∼ 30 microns), high beam charge (3 nC), and small focal spot size (s r = 10 microns) will offer unique scientific opportunities. For more detailed information about the SABER facility and an overview of some of the science possible take a look at the SABER proposal. Initial experiments with electrons could start as early as 2007. A central goal of SABER is to provide a facility responsive to the research needs of its users. The workshop's purposes are to introduce SABER to the potential user community and to explore the range of experiments that are possible. This is an opportunity for the research community to provide input about science at SABER and on the required beam parameters and infrastructure

  17. Selected ground-water data for Yucca Mountain Region, southern Nevada and eastern California, through December 22

    International Nuclear Information System (INIS)

    La Camera, R.J.; Westenburg, C.L.

    1994-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site-Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, ground-water quality at 19 sites, and ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented. Data on ground-water levels, discharges, and withdrawals collected by other agencies (or as part of other programs) are included to further indicate variations through time at selected monitoring locations. Data are included in this report from 1910 through 1992

  18. Data from theodolite measurements of creep rates on San Francisco Bay region faults, California, 1979-2012

    Science.gov (United States)

    McFarland, Forrest S.; Lienkaemper, James J.; Caskey, S. John

    2009-01-01

    Our purpose is to annually update our creep-data archive on San Francisco Bay region active faults for use by the scientific research community. Earlier data (1979-2001) were reported in Galehouse (2002) and were analyzed and described in detail in a summary report (Galehouse and Lienkaemper, 2003). A complete analysis of our earlier results obtained on the Hayward Fault was presented in Lienkaemper, Galehouse and Simpson (2001) and updated in Lienkaemper and others (2012). Lienkaemper and others (2014a) provide a new overview and analysis of fault creep along all sections of the northern San Andreas Fault system, from which they estimate by how much fault creep reduces the seismic hazard for each fault section.

  19. Joint innversion of seismic and magnetotelluric data in the Parkfield Region of California using the normalized cross-gradient constraint

    Science.gov (United States)

    Bennington, Ninfa L.; Zhang, Haijiang; Thurber, Cliff; Bedrosian, Paul A.

    2015-01-01

    We present jointly inverted models of P-wave velocity (Vp) and electrical resistivity for a two-dimensional profile centered on the San Andreas Fault Observatory at Depth (SAFOD). Significant structural similarity between main features of the separately inverted Vp and resistivity models is exploited by carrying out a joint inversion of the two datasets using the normalized cross-gradient constraint. This constraint favors structurally similar Vp and resistivity images that adequately fit the seismic and magnetotelluric (MT) datasets. The new inversion code, tomoDDMT, merges the seismic inversion code tomoDD and the forward modeling and sensitivity kernel subroutines of the MT inversion code OCCAM2DMT. TomoDDMT is tested on a synthetic dataset and demonstrates the code’s ability to more accurately resolve features of the input synthetic structure relative to the separately inverted resistivity and velocity models. Using tomoDDMT, we are able to resolve a number of key issues raised during drilling at SAFOD. We are able to infer the distribution of several geologic units including the Salinian granitoids, the Great Valley sequence, and the Franciscan Formation. The distribution and transport of fluids at both shallow and great depths is also examined. Low values of velocity/resistivity attributed to a feature known as the Eastern Conductor (EC) can be explained in two ways: the EC is a brine-filled, high porosity region, or this region is composed largely of clay-rich shales of the Franciscan. The Eastern Wall, which lies immediately adjacent to the EC, is unlikely to be a fluid pathway into the San Andreas Fault’s seismogenic zone due to its observed higher resistivity and velocity values.

  20. Landslides, Floods, and Marine Effects of the Storm of January 3-5, 1982, in the San Francisco Bay Region, California

    Science.gov (United States)

    Ellen, Stephen D.; Wieczorek, Gerald F.

    1988-01-01

    A catastrophic rainstorm in central California on January 3-5,1982, dropped as much as half the mean annual precipitation within a period of about 32 hours, triggering landslides and floods throughout 10 counties in the vicinity of the San Francisco Bay. More than 18,000 of the slides induced by the storm transformed into debris flows that swept down hillslopes or drainages with little warning. Debris flows damaged at least 100 homes, killed 14 residents, and carried a 15th victim into a creek. Shortly after rainfall ceased, more than 459,000 m3 of earth and rock slid from a mountainside above the community of Love Creek in Santa Cruz County, burying 10 people in their homes. Throughout the bay region, thousands of people vacated homes in hazardous areas, entire communities were isolated as roads were blocked, public water systems were destroyed, and power and telephone services were disrupted. Altogether, the storm damaged 6,300 homes, 1,500 businesses, and tens of kilometers of roads, bridges, and communication lines. Preliminary rough estimates of total storm damage, compiled for emergency purposes within 2 weeks of the storm, exceeded $280 million. Carefully documented direct costs from landslides exceeded $66 million; total costs from landslides certainly were greater and probably constituted a much larger proportion of the total storm damage than suggested by these disparate figures. Landslides accounted for 25 of the 33 deaths attributed to the storm.

  1. Ciguatera fish poisoning. A southern California epidemic.

    Science.gov (United States)

    Barton, E D; Tanner, P; Turchen, S G; Tunget, C L; Manoguerra, A; Clark, R F

    1995-01-01

    Ciguatera fish poisoning results from the bioconcentration of a variety of toxins produced by marine dinoflagellates. Signs and symptoms vary widely, but it usually presents as gastrointestinal and neurologic complaints beginning shortly after the ingestion of fish containing the toxins. Symptoms may persist for months and sometimes even years. Although cases have been reported throughout the United States, epidemics are most common along tropical and subtropical coasts and usually involve the ingestion of large carnivorous fish. We review the literature and report the first epidemic of 25 cases of ciguatera fish poisoning presenting to area hospitals in Southern California that were successfully tracked by the Department of Health Services and isolated to fish caught off the coast of Baja California, Mexico. Images Figure 1. PMID:7667980

  2. Kino en California: 1681-1686

    Directory of Open Access Journals (Sweden)

    Gabriel Gómez Padilla

    2014-01-01

    Full Text Available En este artículo se plantea un doble pro - pósito: exponer la participación del jesuita en la expedición de Isidro Atondo y Anti - llón a la Baja California y rendir tributo académico a la memoria de Miguel Mathes por su labor documental sobre Eusebio Francisco Kino. Se tratan los intentos de la Corona española por colonizar California y también se ofrece una breve biografía de Atondo para contextuar los documentos usados, los cuales van desde las capitulaciones de Atondo hasta la implementación del proyecto seri , ideado por Kino para luchar por el derecho de los californios a ser evangelizados.

  3. Monitoring of the water quality of the Surata River in the mining area of Vetas and California

    International Nuclear Information System (INIS)

    Gomez, Vladimir Illich

    2004-01-01

    The regional autonomous corporation for the defense of the Bucaramanga plateau, environmental authority in the area of influence of the Mining District of Vetas and California, exercises among other activities, the pursuit and control to the auriferous exploitations. Two of the components of this pursuit are: the monitoring of the water quality of the Surata River, final receiver of the effusions coming from of the mineral benefit and the discharges control of cyanidation sand or cyanidation lines, by means of the monthly programming of daily discharges for mining company; in order to diminish the events of high cyanide concentrations in the hydraulic averages and to reduce the cyanide consumptions for the recovery of gold. The mining exploitations of the municipality pour their residuals to the Vetas River, while those of the Municipality of California, pour them to the gulch La Baja, flowing of the Vetas River who in turn is flowing of the Surata River, that supplies a part of the system of aqueduct of the Bucaramanga Municipality. The water quality of mining effusions is determined in three monitored points on the gulch La Baja, the Vetas River and the Surata River; additionally it is made a sampling and analysis of silts in four points on the same currents. The sampling frequency for the water quality is monthly, while for the silts analysis is biweekly. This monitoring is carried out from the year 1988, although it has suffered some interruptions in the time. The technique of water sampling is punctual, integrated to the wide of the bed and without seating capacity, the taking of silts is punctual and integrated to the wide of the bed and without seating capacity, these samples are preserved and transported to the laboratory of waters and soils of the CDMB, where the following parameters are analyzed: for the water sample, mercury, free cyanide and total cyanide, suspended solids, turbidity, pH and conductivity; for the sample of silts only mercury is analyzed

  4. LEED, Its Efficacy and Fallacy in a Regional Context—An Urban Heat Island Case in California

    Directory of Open Access Journals (Sweden)

    Min Ho Shin

    2017-09-01

    Full Text Available The use of energy in the building sector has increased rapidly over the past two decades. Accordingly, various building assessment methods have developed in green building practices. However, the questions still remain in regard to how positively green buildings affect regional surroundings. This study investigates the possible relationship between LEED-certified buildings and urban heat island effect. Using GIS with spatial regression, the study found that constructing an LEED building in a 30-m boundary could possibly lower the temperature of the surrounding environment by 0.35 °C. Also, having a higher certification level, such as Gold or Platinum, increased the lowering effect by 0.48 °C, while a lower certification level, such as Certified or Silver, had a lowering effect of 0.26 °C. Although LEED has gained a substantial amount of interest and skepticism at the same time, the study results could be a potential sign that the Sustainable Sites Credits or energy-efficient materials play a positive role in lowering the temperature.

  5. Applying a regional hydrology model to evaluate locations for groundwater replenishment with hillslope runoff under different climate and land use scenarios in an agricultural basin, central coastal California

    Science.gov (United States)

    Beganskas, S.; Young, K. S.; Fisher, A. T.; Lozano, S.; Harmon, R. E.; Teo, E. K.

    2017-12-01

    We are applying a regional hydrology model, Precipitation-Runoff Modeling System (PRMS), to evaluate locations for groundwater replenishment with hillslope runoff in the Pajaro Valley Groundwater Basin (PVGB), central coastal California. Stormwater managed aquifer recharge (MAR) projects collect hillslope runoff before it reaches a stream and infiltrate it into underlying aquifers, improving groundwater supply. The PVGB is a developed agricultural basin where groundwater provides >85% of water for irrigation and municipal needs; stormwater-MAR projects are being considered to address chronic overdraft and saltwater intrusion. We are applying PRMS to assess on a subwatershed scale (10-100 ha; 25-250 acres) where adequate runoff is generated to supply stormwater-MAR in coincidence with suitable conditions for infiltration and recharge. Data from active stormwater-MAR projects in the PVGB provide ground truth for model results. We are also examining how basinwide hydrology responds to changing land use and climate, and the potential implications for future water management. To prepare extensive input files for PRMS models, we developed ArcGIS and Python tools to delineate a topographic model grid and incorporate high-resolution soil, vegetation, and other physical data into each grid region; we also developed tools to analyze and visualize model output. Using historic climate records, we generated dry, normal, and wet climate scenarios, defined as having approximately 25th, 50th, and 75th percentile annual rainfall, respectively. We also generated multiple land use scenarios by replacing developed areas with native vegetation. Preliminary results indicate that many parts of the PVGB generate significant runoff and have suitable infiltration/recharge conditions. Reducing basinwide overdraft by 10% would require collecting less than 5% of total hillslope runoff, even during the dry scenario; this demonstrates that stormwater-MAR could be an effective water management

  6. GPS Installation Progress in the Northern California Region of the Plate Boundary Observatory Coyle, B., Basset, A., Williams, T., Enders, M., Feaux, K., Jackson, M.

    Science.gov (United States)

    Coyle, B.; Basset, A.; Enders, M.; Williams, T.; Feaux, K.; Jackson, M.

    2005-12-01

    The Plate Boundary Observatory (PBO) is the geodetic component of the NSF funded EarthScope Project . The final PBO GPS network will comprise 875 continuously operating GPS stations installed throughout the Western US and Alaska. There are 435 stations planned for California with 229 of these in Northern California (NCA). This poster will present the past year's progress of GPS installations in NCA. At the end of the first year of the Project, PBO NCA installed 12 stations. During the second year, another 56 were installed for a total of 68 stations including 18 SDBM, and 50 DDBM. We have sited 128 stations, submitted 112 permit applications and received 73 permits. A particularly important statistic for planning our schedules is the time lag between reconnaissance and permit accepted; our average thus far is 137 days. We have been particularly successful locating stations on Caltrans Rights of Way with 20 Stations built, 3 sites permitted and 5 permits pending. Other land use partners include: East Bay Regional Parks - 8 Stations built and 2 sites permitted, Bureau of Land Management - 5 Stations built, 3 permits pending, Water Municipalities - 4 Stations built, 3 sites permitted and 4 permits pending, and Airports - 4 Stations built and 3 permits pending. Highlights from last year: On September 28, 2004 a Mw 6.0 earthquake occurred on the San Andreas Fault seven miles southeast of the town of Parkfield, CA. Field crews from the Northern and Southern California offices of PBO began the site reconnaissance and permitting process the day after the earthquake and installation of the first Station was begun within 36 hours and completed the following day. In total, 5 Stations were installed by the first week of November. On June 14, 2045 a Mw 7.1 earthquake occurred on the Gorda Plate, approximately 100 miles NW of Eureka. PBO stations, P158, P162, P169 and P170, recorded coseismic deformation associated with this event. We plan to have 127 stations built by the end

  7. California State Waters Map Series—Offshore of Santa Cruz, California

    Science.gov (United States)

    Cochrane, Guy R.; Dartnell, Peter; Johnson, Samuel Y.; Erdey, Mercedes D.; Golden, Nadine E.; Greene, H. Gary; Dieter, Bryan E.; Hartwell, Stephen R.; Ritchie, Andrew C.; Finlayson, David P.; Endris, Charles A.; Watt, Janet T.; Davenport, Clifton W.; Sliter, Ray W.; Maier, Katherine L.; Krigsman, Lisa M.; Cochrane, Guy R.; Cochran, Susan A.

    2016-03-24

    upper Quaternary shelf, estuarine, and fluvial sediments deposited as sea level fluctuated in the late Pleistocene. The inner shelf is characterized by bedrock outcrops that have local thin sediment cover, the result of regional uplift, high wave energy, and limited sediment supply. The midshelf occupies part of an extensive, shore-parallel mud belt. The thickest sediment deposits, inferred to consist mainly of lowstand nearshore deposits, are found in the southeastern and northwestern parts of the map area.Coastal sediment transport in the map area is characterized by northwest-to-southeast littoral transport of sediment that is derived mainly from ephemeral streams in the Santa Cruz Mountains and also from local coastal-bluff erosion. During the last approximately 300 years, as much as 18 million cubic yards (14 million cubic meters) of sand-sized sediment has been eroded from the area between Año Nuevo Island and Point Año Nuevo and transported south; this mass of eroded sand is now enriching beaches in the map area. Sediment transport is within the Santa Cruz littoral cell, which terminates in the submarine Monterey Canyon.Benthic species observed in the Offshore of Santa Cruz map area are natives of the cold-temperate biogeographic zone that is called either the “Oregonian province” or the “northern California ecoregion.” This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, the eastern limb of the North Pacific subtropical gyre that flows from southern British Columbia to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 300 km south of the map area), although its associated

  8. Simulation of net infiltration and potential recharge using a distributed-parameter watershed model of the Death Valley region, Nevada and California

    Science.gov (United States)

    Hevesi, Joseph A.; Flint, Alan L.; Flint, Lorraine E.

    2003-01-01

    This report presents the development and application of the distributed-parameter watershed model, INFILv3, for estimating the temporal and spatial distribution of net infiltration and potential recharge in the Death Valley region, Nevada and California. The estimates of net infiltration quantify the downward drainage of water across the lower boundary of the root zone and are used to indicate potential recharge under variable climate conditions and drainage basin characteristics. Spatial variability in recharge in the Death Valley region likely is high owing to large differences in precipitation, potential evapotranspiration, bedrock permeability, soil thickness, vegetation characteristics, and contributions to recharge along active stream channels. The quantity and spatial distribution of recharge representing the effects of variable climatic conditions and drainage basin characteristics on recharge are needed to reduce uncertainty in modeling ground-water flow. The U.S. Geological Survey, in cooperation with the Department of Energy, developed a regional saturated-zone ground-water flow model of the Death Valley regional ground-water flow system to help evaluate the current hydrogeologic system and the potential effects of natural or human-induced changes. Although previous estimates of recharge have been made for most areas of the Death Valley region, including the area defined by the boundary of the Death Valley regional ground-water flow system, the uncertainty of these estimates is high, and the spatial and temporal variability of the recharge in these basins has not been quantified. To estimate the magnitude and distribution of potential recharge in response to variable climate and spatially varying drainage basin characteristics, the INFILv3 model uses a daily water-balance model of the root zone with a primarily deterministic representation of the processes controlling net infiltration and potential recharge. The daily water balance includes precipitation

  9. Mercury Bioaccumulation in Fish in a Region Affected by Historic Gold Morning: The South Yuba River, Deer Creek, and Bear River Watersheds, California, 1999

    National Research Council Canada - National Science Library

    May, Jason T; Hothem, Roger L; Alpers, Charles N; Law, Matthew A

    2000-01-01

    ... Francisco Bay of northern California. Methylmercury is of particular concern because it is the most prevalent form of mercury in fish and is a potent neurotoxin that bioaccumulates at successive trophic levels within food webs...

  10. Large, high-intensity fire events in Southern California shrublands: Debunking the fine-grain age patch model

    Science.gov (United States)

    Keeley, J.E.; Zedler, P.H.

    2009-01-01

    We evaluate the fine-grain age patch model of fire regimes in southern California shrublands. Proponents contend that the historical condition was characterized by frequent small to moderate size, slow-moving smoldering fires, and that this regime has been disrupted by fire suppression activities that have caused unnatural fuel accumulation and anomalously large and catastrophic wildfires. A review of more than 100 19th-century newspaper reports reveals that large, high-intensity wildfires predate modern fire suppression policy, and extensive newspaper coverage plus first-hand accounts support the conclusion that the 1889 Santiago Canyon Fire was the largest fire in California history. Proponents of the fine-grain age patch model contend that even the very earliest 20th-century fires were the result of fire suppression disrupting natural fuel structure. We tested that hypothesis and found that, within the fire perimeters of two of the largest early fire events in 1919 and 1932, prior fire suppression activities were insufficient to have altered the natural fuel structure. Over the last 130 years there has been no significant change in the incidence of large fires greater than 10000 ha, consistent with the conclusion that fire suppression activities are not the cause of these fire events. Eight megafires (???50 000 ha) are recorded for the region, and half have occurred in the last five years. These burned through a mosaic of age classes, which raises doubts that accumulation of old age classes explains these events. Extreme drought is a plausible explanation for this recent rash of such events, and it is hypothesized that these are due to droughts that led to increased dead fine fuels that promoted the incidence of firebrands and spot fires. A major shortcoming of the fine-grain age patch model is that it requires age-dependent flammability of shrubland fuels, but seral stage chaparral is dominated by short-lived species that create a dense surface layer of fine

  11. Mercury methylation, export and bioaccumulation in rice agriculture - model results from comparative and experimental studies in 3 regions of the California Delta, USA

    Science.gov (United States)

    Windham-Myers, L.; Fleck, J.; Eagles-Smith, C.; Ackerman, J.

    2013-12-01

    Seasonally flooded wetland ecosystems are often poised for mercury (Hg) methylation, thus becoming sources of methylmercury (MeHg) to in situ and downstream biota. The seasonal flooding associated with cultivation of rice (Oryza sativa) also generates MeHg, which may be stored in sediment or plants, bioaccumulated into fauna, degraded or exported, depending on hydrologic and seasonal conditions. While many U.S. waters are regulated for total Hg concentrations based on fish targets, California's Sacramento-San Joaquin Delta (Delta) will soon implement the first MeHg total maximum daily load (TMDL) control program. Since 2007, a conceptual model (DRERIP-MCM) and several ecosystem-level studies have been advanced to better understand the mechanisms behind Hg methylation, export and bioaccumulation within Delta wetlands, including rice agriculture. Three Delta rice-growing regions (Yolo Bypass, Cosumnes River, Central Delta) of varied soil characteristics, mining influences and hydrology, were monitored over full crop years to evaluate annual MeHg dynamics. In addition to fish tissue Hg accumulation, a broad suite of biogeochemical and hydrologic indices were assessed and compared between wetland types, seasons, and regions. In general, Delta rice fields were found to export MeHg during the post-harvest winter season, and promote MeHg uptake in fish and rice grain during the summer growing season. As described in a companion presentation (Eagles-Smith et al., this session), the experimental Cosumnes River study suggests that rice-derived dissolved organic carbon (DOC) fuels MeHg production and uptake into aquatic foodwebs. Explicit DRERIP-MCM linkages for the role of rice-DOC in MeHg production, export and bioaccumulation were verified across two summers (2011, 2012): rice biomass and root productivity influenced porewater DOC availability and microbial processes, which drove sediment MeHg production and flux to surface water, promoting MeHg bioaccumulation in fish

  12. Mortality trends and risk of dying from pulmonary tuberculosis in the 7 socioeconomic regions and the 32 States of Mexico, 2000-2009.

    Science.gov (United States)

    Sánchez-Barriga, Juan Jesús

    2015-01-01

    Tuberculosis (TB) is a world public health problem that still has a high morbidity and mortality rate mainly in countries with significant wealth gaps. Poverty, malnutrition, HIV infection, drug resistance, diabetes and addictions (mainly alcoholism) have been seen to contribute to the persistence of TB as an important health problem in Mexico. Death certificates associated with pulmonary tuberculosis (PTB) for 2000-2009 were obtained from the National Information System of the Secretariat of Health. Rates of mortality nationwide, by state, and by socioeconomic region were calculated. The strength of association between states where individuals resided, socioeconomic regions, and education with mortality from PTB was determined. Age-adjusted mortality rates per 100,000 inhabitants who died from PTB decreased from 4.1 to 2 between 2000 and 2009. Men (67.7%) presented higher mortality than women (32.3%). Individuals failing to complete elementary education presented a higher risk of dying from PTB (RR 1.08 [95%CI: 1.05-1.12]). The socioeconomic region and the entities with the strongest association were region 1, 5, Chiapas and Baja California. Region 1 in 2007 presented RR 7.34 (95%CI: 5.32-10.13), and region 5 in 2009 had RR 10.08 (95%CI: 6.83-14.88). In Mexico, the annual mortality rate from PTB decreased. Men presented higher mortality than women. Individuals failing to complete elementary education showed a higher risk of dying from PTB. The states and regions of Mexico that presented a stronger association with mortality from PTB were Chiapas and Baja California, region 1 and 5. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  13. Studies of geology and hydrology in the Basin and Range province, southwestern United States, for isolation of high-level radioactive waste-characterization of the Death Valley region, Nevada and California

    International Nuclear Information System (INIS)

    Bedinger, M.S.; Sargent, K.A.; Langer, W.H.

    1989-01-01

    The Death Valley region, Nevada and California, in the Basin and Range province, is an area of about 80,200 sq km located in southern Nevada and southeastern California. Precambrian metamorphic and intrusive basement rocks are overlain by a thick section of Paleozoic clastic and evaporitic sedimentary rocks. Mesozoic and Cenozoic rocks include extrusive and intrusive rocks and clastic sedimentary rocks. Structural features within the Death Valley indicate a long and complex tectonic evolution from late Precambrian to the present. Potential repository host media in the region include granite and other coarse-grained plutonic rocks, ashflow tuff, basaltic and andesitic lava flows, and basin fill. The Death Valley region is composed largely of closed topographic basins that are apparently coincident with closed groundwater flow systems. In these systems, recharge occurs sparingly at higher altitudes by infiltration of precipitation or by infiltration of ephemeral runoff. Discharge occurs largely by spring flow and by evaporation and transpiration in the playas. Death Valley proper, for which the region was named, is the ultimate discharge area for a large, complex system of groundwater aquifers that occupy the northeastern part of the region. The deepest part of the system consists of carbonate aquifers that connect closed topographic basins at depth. The discharge from the system occurs in several intermediate areas that are geomorphically, stratigraphically, and structurally controlled. Ultimately, most groundwater flow terminates by discharge to Death Valley; groundwater is discharged to the Colorado River from a small part of the region

  14. Ca Biodiversity Council Bioregions (INACC Regions)

    Data.gov (United States)

    California Natural Resource Agency — California regions developed by the Inter-agency Natural Areas Coordinating Committee (INACC) were digitized from a 1:1,200,000 California Department of Fish and...

  15. Socioeconomic determinants of fertility: selected Mexican regions, 1976-1977.

    Science.gov (United States)

    Pick, J B; Butler, E W; Pavgi, S

    1988-01-01

    Cumulative fertility is analyzed for 4 regions of Mexico, based on World Fertility Survey data of 1976-77; the state of Baja California, the Northwest region, the State of Jalisco, and the Northeast region. Based on stepwise regression methodology, the study compares results for 12 subsamples of married respondents, 3 age categories by 4 regions. The dependent variables are children ever born and children ever born in the last 5 years. Migration, urban, educational, and occupational variables are included as independent variables. Regression results reveal level of education is the major, and negative, influence on fertility. Other results include specific negative effects for prior occupation, size of place of residence, and childhood place of residence. Fertility effects appear different for migration origin and destination regions, but more similar for younger ages. Effects of migration on fertility are small. Mean fertility as measured by children ever born was 4.34 for the 1976-77 World Fertility Survey samples versus 3.69 for the Mexican census of 1980. Fertility varied somewhat by region with the highest and lowest values in Jalisco and the Northeast, respectively. Expected age-related changes in fertility were noted.

  16. Studi Respon Seismik Penggunaan Steel Slit Damper (SSD pada Portal Baja

    Directory of Open Access Journals (Sweden)

    Lisa Ika Arumsari

    2012-09-01

    Full Text Available Salah satu metode yang dapat digunakan untuk mengurangi dampak dari beban gempa terhadap portal baja adalah menggunakan peredam. Steel Slit Damper (SSD adalah salah satu jenis peredam yang dibuat dari sejumlah pelat baja lunak berbentuk segi-4 yang dimodelkan sebagai pegas-pegas yang disusun secara seri. Energi akibat gempa disalurkan melalui strip-strip damper yang mudah meleleh ketika perangkat mengalami deformasi inelastis siklik. SSD mendisipasi energi melalui pembentukan sendi plastis atau pelelehan pelat damper. Pada penelitian ini dilakukan analisa respon seismik Steel Slit Damper (SSD pada portal baja 1 lantai yang menerima beban lateral berupa beban gempa, dengan membandingkan portal baja konvensional, portal baja inverted-v, dan portal baja dengan SSD. Hasil analisa menunjukkan bahwa gaya geser, gaya normal, dan momen yang dihasikan portal dengan SSD lebih kecil hingga 80,49% dari gaya-gaya yang dihasilkan portal konvensional, tetapi gaya-gaya tersebut masih lebih besar daripada yang dihasilkan portal inverted-V. Portal dengan SSD dapat memperkecil simpangan sebesar 94,12% pada portal konvensional dan sebesar 33,33% pada portal bracing inverted-v. Hasil penelitian juga menunjukkan bahwa portal SSD memiliki daktilitas 105,85% lebih tinggi dari portal konvensional dan 298,67% lebih tinggi dari portal bracing inverted-v

  17. Digital Elevation Model (DEM) file of topographic elevations for the Death Valley region of southern Nevada and southeastern California processed from US Geological Survey 1-degree Digital Elevation Model data files

    International Nuclear Information System (INIS)

    Turner, A.K.; D'Agnese, F.A.; Faunt, C.C.

    1996-01-01

    Elevation data have been compiled into a digital data base for an ∼100,000-km 2 area of the southern Great Basin, the Death Valley region of southern Nevada, and SE Calif., located between lat 35 degree N, long 115 degree W, and lat 38 degree N, long 118 degree W. This region includes the Nevada Test Site, Yucca Mountain, and adjacent parts of southern Nevada and eastern California and encompasses the Death Valley regional ground-water system. Because digital maps are often useful for applications other than that for which they were originally intended, and because the area corresponds to a region under continuing investigation by several groups, these digital files are being released by USGS

  18. Final report for SERDP project RC-1648: new tools for estimating and managing local/regional air quality impacts of prescribed burns. University of California - Riverside

    Science.gov (United States)

    W. Miller; D. Weise; S. Mahalingam; M. Princevac; R. Yokelson; W. Hao; D. Cocker; H. Jung; G. Tonnesen; S. Urbanski; I. Burling; S. Hosseini; S. Akagi

    2013-01-01

    Gaseous and particulate emissions were measured for a variety of chaparral and Madrean oak woodland fuel types in a series of laboratory and field experiments in California and Arizona. Emissions were measured using state of the art ground-based and aircraft-based sampling systems. Emission factors were determined for many new chemical species for the fuels....

  19. Isla Guadalupe, Mexico (GUAX, SCIGN/PBO) a Relative Constraint for California Borderland and Northern Gulf of California Motions.

    Science.gov (United States)

    Gonzalez-Garcia, J. J.

    2004-12-01

    Using ITRF2000 as a common reference frame link, I analyzed survey mode and permanent GPS published results, together with SOPAC public data and results (http://sopac.ucsd.edu), in order to evaluate relative present day crustal deformation in California and northern Mexico. The crustal velocity field of Mexico (Marquez-Azua and DeMets, 2003) obtained from continuous GPS measurements conducted by Instituto Nacional de Geografia e Informatica (INEGI) for 1993-2001, was partially used. The preferred model for an instantaneous rigid motion between North-America and Pacific plates (NAPA), is obtained using results of Isla Guadalupe GPS surveys (1991-2002) giving a new constraint for Pacific plate (PA) motion (Gonzalez-Garcia et al., 2003). It produces an apparent reduction of 1 mm/yr in the absolute motion in the border zone between PA and North-America (NA) plates in this region, as compared with other GPS models (v.g. Prawirodirdjo and Bock, 2004); and it is 3 mm/yr higher than NNRNUVEL-1A. In the PA reference frame, westernmost islands from San Francisco (FARB), Los Angeles (MIG1), and Ensenada (GUAX); give current residuals of 1.8, 1.7 and 0.9 mm/yr and azimuths that are consistent with local tectonic setting, respectively. In the NA reference frame, besides the confirmation of 2 mm/yr E-W extension for the southern Basin and Range province in northern Mexico; a present day deformation rate of 40.5 mm/yr between San Felipe, Baja California (SFBC) and Hermosillo, Sonora, is obtained. This rate agrees with a 6.3 to 6.7 Ma for the "initiation of a full sea-floor spreading" in the northern Gulf of