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Sample records for caspi cuchuna sierra

  1. Nueva información petrogenética de las basanitas de Caspi Cuchuna, Sierra Norte de Córdoba New petrogenetic information of the Caspi Cuchuna basanites, Sierra Norte de Córdoba

    Directory of Open Access Journals (Sweden)

    M.S. O'Leary

    2006-09-01

    Full Text Available Se presenta nueva información mineralógica y geoquímica de los diques básicos alcalinos situados en el sector centro-occidental del batolito Sierra Norte-Ambargasta, en el paraje Caspi Cuchuna. Se establece su composición basanítica y de acuerdo a la mineraloquímica de los silicatos ferromagnesianos constitutivos, olivino (Fo83 y diópsido (Wo49En37Fs14, se propone una cristalización en condiciones de alta temperatura y alta presión en sus etapas iniciales, parámetros que decrecieron junto con un aumento de la fugacidad de oxígeno, posiblemente en condiciones cercanas a las de emplazamiento. Los contenidos de Cr (333 ppm, Ni (183 ppm y MgO (9,13% indican características relativamente primarias de esta roca, con fraccionamiento de olivino, piroxeno y magnetita. El empobrecimiento de ETR pesados revela la presencia de granate residual en la fuente y el importante enriquecimiento de elementos incompatibles (Cs, Rb y Ba indicaría contaminación por corteza durante el ascenso y emplazamiento. Su impronta geoquímica lo ubica en un ambiente de intraplaca (WPB y muestra un patrón multielemental comparable a los basaltos alcalinos de intraplaca ubicados al este de la zona volcánica activa andina, en un régimen extensional. Sus características geoquímicas sugieren una derivación por fusión parcial de litósfera subcontinental con posible aporte de corteza continental.New mineralogical and geochemical data from the Caspi Cuchuna basic alkaline dykes located in the central-western region of the Sierra Norte-Ambargasta batholith are presented. The petrography and bulk rock chemistry classify these dikes as basanites. Mineral chemistry data for selected olivine and clinopyroxene phenocrysts suggest high temperature and high pressure conditions for initial crystallization; the system evolved towards lower pressure and temperature along with an increase of the oxygen fugacity, possibly approaching emplacement conditions. The Cr (333 ppm, Ni

  2. Nueva información petrogenética de las basanitas de Caspi Cuchuna, Sierra Norte de Córdoba

    Directory of Open Access Journals (Sweden)

    M.S. O'Leary

    2006-09-01

    Full Text Available Se presenta nueva información mineralógica y geoquímica de los diques básicos alcalinos situados en el sector centro-occidental del batolito Sierra Norte-Ambargasta, en el paraje Caspi Cuchuna. Se establece su composición basanítica y de acuerdo a la mineraloquímica de los silicatos ferromagnesianos constitutivos, olivino (Fo83 y diópsido (Wo49En37Fs14, se propone una cristalización en condiciones de alta temperatura y alta presión en sus etapas iniciales, parámetros que decrecieron junto con un aumento de la fugacidad de oxígeno, posiblemente en condiciones cercanas a las de emplazamiento. Los contenidos de Cr (333 ppm, Ni (183 ppm y MgO (9,13% indican características relativamente primarias de esta roca, con fraccionamiento de olivino, piroxeno y magnetita. El empobrecimiento de ETR pesados revela la presencia de granate residual en la fuente y el importante enriquecimiento de elementos incompatibles (Cs, Rb y Ba indicaría contaminación por corteza durante el ascenso y emplazamiento. Su impronta geoquímica lo ubica en un ambiente de intraplaca (WPB y muestra un patrón multielemental comparable a los basaltos alcalinos de intraplaca ubicados al este de la zona volcánica activa andina, en un régimen extensional. Sus características geoquímicas sugieren una derivación por fusión parcial de litósfera subcontinental con posible aporte de corteza continental.

  3. Long-term effects of course-embedded undergraduate research: The CASPiE longitudinal study

    Science.gov (United States)

    Szteinberg, Gabriela A.

    The Center for Authentic Science Practice in Education (CASPiE) is a National Science Foundation funded initiative that seeks to introduce first- and second-year undergraduate students to research in their mainstream laboratory courses. To investigate the effects of this research-based curriculum, a longitudinal study was initiated at Purdue University (PU) and University of Illinois-Chicago (UIC), where CASPiE was implemented in a portion of laboratory sections of a general chemistry course (CHEM 116 at PU/CHEM 114 at UIC). The study examined the long-term effects of the CASPiE program on students' chemistry course performance, research involvement, and retention in STEM majors and future careers. The results of the academic records analyses showed that PU CASPiE students from the opt-in semesters, i.e. those when students chose to enroll in the CASPiE sections, were higher-achieving students from the beginning of their college years and performed significantly higher than the students in the traditional sections. There were no significant differences in chemistry course performance among PU students from the randomly assigned semester. However, looking from the first semester chemistry course to the upper 300 level chemistry courses, randomly assigned PU students from the traditional sections had a significant performance decrease. The CASPiE students had a performance decrease that was not significant. At UIC, there were no significant differences between CASPiE and traditional students' chemistry performance. Analyses of the academic records also revealed that there were no differences in STEM major retention between CASPiE and traditional students, from both PU and UIC. However, CASPiE students from UIC and the ones from the opt-in sections at PU graduated faster in average than traditional students. Students' responses to an online survey showed that there were no differences in students' choice of future plans in STEM or non-STEM fields (such as graduate or

  4. Implementing the CASPiE course-based research experience at the United States Military Academy: Affective responses and effects on critical thinking

    Science.gov (United States)

    Chase, Anthony Michael

    The Center for Authentic Science Practices in Education (CASPiE) pioneered a course-based research experience approach to teaching chemistry laboratory courses. The method had previously been studied in a variety of institutional settings. Recently, the United States Military Academy at West Point decided to develop CASPiE-style modules for the introductory honors chemistry course. This research setting presents clean experimental-control comparisons and a group of faculty who were completely new to the method. Equipping students with authentic research experiences early in their education is important regardless of the institution. However, cadets at a military academy must make decisions relatively early (the outset of their second year) as to what their career trajectory will be as eventual officers. In the new CASPiE-based experience, cadets are given the opportunity to select from one of three different modules (analytical chemistry, toxicology, and chemical engineering) in which to participate during the course. These three modules represent subsections of an overall Army waste-to-energy research project. Cadets generate unique hypotheses, real data, and research posters towards the advancement of the project. Posters are then presented in a session. that includes an audience of project stakeholders, course instructors, and other academy faculty and staff. Here, I will present my research methods, evaluative procedures, and findings in the affective domain, critical thinking, and laboratory content comprehension.

  5. Guide to Using Sierra

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Ryan Phillip [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Agelastos, Anthony Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, Joel D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    Sierra is an engineering mechanics simulation code suite supporting the Nation's Nuclear Weapons mission as well as other customers. It has explicit ties to Sandia National Labs' workfow, including geometry and meshing, design and optimization, and visualization. Dis- tinguishing strengths include "application aware" development, scalability, SQA and V&V, multiple scales, and multi-physics coupling. This document is intended to help new and existing users of Sierra as a user manual and troubleshooting guide.

  6. Returnees in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Claudena Skran

    2008-12-01

    Full Text Available Over ten years of brutal civil war displaced approximately4.5 million people, about half Sierra Leone’s population.After the conflict ended in 2001, UNHCR facilitated theparticipation of both returnee refugees and returnee IDPsin community-level reconstruction projects.

  7. Sierra Structural Dynamics Theory Manual

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Garth M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-19

    Sierra/SD provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of structural systems. This manual describes the theory behind many of the constructs in Sierra/SD. For a more detailed description of how to use Sierra/SD , we refer the reader to Sierra/SD, User's Notes . Many of the constructs in Sierra/SD are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Sierra/SD are specific to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programmer notes manual, the user's notes and of course the material in the open literature. This page intentionally left blank.

  8. Area Handbook for Sierra Leone,

    Science.gov (United States)

    1976-01-01

    During its fifteen years of independence since 1961, Sierra Leone has had some difficulty in maintaining political stability and in generating...performance has been comparatively weak. By the mid-1970s, however, there were indications that it might improve. The Area Handbook for Sierra Leone

  9. Sierra Nevada Subregional Boundary - Sierra Nevada Conservancy [ds542

    Data.gov (United States)

    California Department of Resources — Sierra Nevada Conservancy (SNC) boundary. The boundary was mapped to correspond with statute AB 2600 (2004) and as re-defined in AB 1201 (2005). Work on the boundary...

  10. Sierra Nevada (Granada, Spain)

    DEFF Research Database (Denmark)

    Gilgado, José D.; Enghoff, Henrik; Tinaut, Alberto;

    2015-01-01

    Millipedes (Diplopoda), with a few notable exceptions, are poor dispersers, showing a very high degree of endemicity, not the least in mountains. The first samplings of the Mesovoid Shallow Substratum (MSS) of the higher altitudes of the Sierra Nevada Mountains (Baetic System, Southern Spain) have...... of Ceratosphys cryodeserti Gilgado, Mauriès & Enghoff n. sp. are here provided, as well as the first data on the humidity and temperature fluctuations in the MSS of this high mountain. The new species is similar to other Baetico-Riffan species, while the only previously known congener from the region, C...... led to the discovery of a high number of millipedes, each of the species present showing a different degree of establishment in this subterranean environment. An update of the knowledge on the millipedes of this region, the first data of the millipede communities in the MSS and the description...

  11. Modeling interfacial fracture in Sierra.

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Arthur A.; Ohashi, Yuki; Lu, Wei-Yang; Nelson, Stacy A. C.; Foulk, James W.,; Reedy, Earl David,; Austin, Kevin N.; Margolis, Stephen B.

    2013-09-01

    This report summarizes computational efforts to model interfacial fracture using cohesive zone models in the SIERRA/SolidMechanics (SIERRA/SM) finite element code. Cohesive surface elements were used to model crack initiation and propagation along predefined paths. Mesh convergence was observed with SIERRA/SM for numerous geometries. As the funding for this project came from the Advanced Simulation and Computing Verification and Validation (ASC V&V) focus area, considerable effort was spent performing verification and validation. Code verification was performed to compare code predictions to analytical solutions for simple three-element simulations as well as a higher-fidelity simulation of a double-cantilever beam. Parameter identification was conducted with Dakota using experimental results on asymmetric double-cantilever beam (ADCB) and end-notched-flexure (ENF) experiments conducted under Campaign-6 funding. Discretization convergence studies were also performed with respect to mesh size and time step and an optimization study was completed for mode II delamination using the ENF geometry. Throughout this verification process, numerous SIERRA/SM bugs were found and reported, all of which have been fixed, leading to over a 10-fold increase in convergence rates. Finally, mixed-mode flexure experiments were performed for validation. One of the unexplained issues encountered was material property variability for ostensibly the same composite material. Since the variability is not fully understood, it is difficult to accurately assess uncertainty when performing predictions.

  12. CPAFFC Delegation Visits Sierra Leone and Cameroon

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>At the invitation of the Sierra Leone-China Friendship Association (SLCFA) and the Ministry of Territorial Administration and Decentralization of Cameroon, a 14-member CPAFFC delegation headed by Wang Daoyu, vice chairman of the Standing Committee of the Shandong Provincial People’s Congress, paid a goodwill visit to Sierra Leone and Cameroon in early December 2005. In Sierra Leone Vice President Solomon Ekuma Berewa, President of the Parliament Edmond Cowan, and Vice Foreign Minister Mohamed Kamara, and in

  13. Aspen Characteristics - Sierra State Parks [ds379

    Data.gov (United States)

    California Department of Resources — The database represents point locations and associated stand assessment data collected within aspen stands on lands administrated by the Sierra District, California...

  14. Reading Comprehension Instruction Practices in Sierra Leone

    NARCIS (Netherlands)

    Hersbach, S.; Denessen, E.J.P.G.; Droop, W.

    2014-01-01

    Aim: In this study an attempt was made to give insight in the way reading comprehension is taught in Sierra Leone. Attention was paid to the didactical strategies and the materials used during reading comprehension instruction. Methodology: Primary school teachers in Sierra Leone (N=43) were observe

  15. My Great Migration from Sierra Leone

    Science.gov (United States)

    Harvard Educational Review, 2011

    2011-01-01

    This article presents the author's personal narrative as an immigrant from Sierra Leone who has undergone so many challenges in life and ended up turning all these obstacles into opportunities. In this article, the author describes his life growing up in Sierra Leone, his first experience of the horrors of war, his life as a student, and his dream…

  16. Sierra/SM theory manual.

    Energy Technology Data Exchange (ETDEWEB)

    Crane, Nathan Karl

    2013-07-01

    Presented in this document are the theoretical aspects of capabilities contained in the Sierra/SM code. This manuscript serves as an ideal starting point for understanding the theoretical foundations of the code. For a comprehensive study of these capabilities, the reader is encouraged to explore the many references to scientific articles and textbooks contained in this manual. It is important to point out that some capabilities are still in development and may not be presented in this document. Further updates to this manuscript will be made as these capabilites come closer to production level.

  17. SIERRA framework version 4 : solver services.

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Alan B.

    2005-02-01

    Several SIERRA applications make use of third-party libraries to solve systems of linear and nonlinear equations, and to solve eigenproblems. The classes and interfaces in the SIERRA framework that provide linear system assembly services and access to solver libraries are collectively referred to as solver services. This paper provides an overview of SIERRA's solver services including the design goals that drove the development, and relationships and interactions among the various classes. The process of assembling and manipulating linear systems will be described, as well as access to solution methods and other operations.

  18. Cholera epidemic threatens Sierra Leone.

    Science.gov (United States)

    Dyer, O

    1995-07-08

    Sierra Leone faces the threat of a major epidemic of cholera with the onset of the rainy season, according to the World Health Organization (WHO). The situation is particularly grave for the two million people displaced by the country's civil war. Already 1709 cases of cholera have been registered in Freetown, with 57 deaths. Freetown's population has doubled since the start of the war in 1991 with 750,000 refugees camping out in the town. The insurgent Revolutionary United Front is now within 32 km of the capital. Provinces are cut off from the capital, medical supplies are scarce. Doctors and aid workers are forced to rely on a private helicopter service for personal transport. As many as 10,000 people were affected by the disease last year. WHO experts predict that pneumonia is likely to claim the lives of many children, and a highly drug resistant strain of Plasmodium falciparum malaria is also looming. The greatest problems are the lack of safe drinking water and the attendant risks of cholera and dysentery. At one site in Freetown the 6000 refugees have to fetch water from a well and have no latrines. As a result there have been 277 cases of cholera and 2 deaths already among that group. The health department has set up five centers to treat cholera in Freetown and is organizing mobile clinics. WHO's Sierra Leone office is assisting the government mobile health teams, which provide free primary care to displaced people. Medicines and vaccines, however, are lacking. Many of the staff of the 13 district health authorities have been displaced to Freetown. Aid agencies such as Medecins Sans Frontieres and Oxfam have stepped into the role in many districts. Ironically, one of the Revolutionary United Front's main demands is for a free national health service.

  19. Running Parallel Discrete Event Simulators on Sierra

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, P. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jefferson, D. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-03

    In this proposal we consider porting the ROSS/Charm++ simulator and the discrete event models that run under its control so that they run on the Sierra architecture and make efficient use of the Volta GPUs.

  20. Aspen Delineation - Sierra State Parks [ds380

    Data.gov (United States)

    California Department of Resources — The database represents delineations of aspen stands associated with stand assessment data (SIERRA_SP_PTS) collected in aspen stands on lands administered by the...

  1. GPS Imaging of Sierra Nevada Uplift

    Science.gov (United States)

    Hammond, W. C.; Blewitt, G.; Kreemer, C.

    2015-12-01

    Recent improvements in the scope and precision of GPS networks across California and Nevada have allowed for uplift of the Sierra Nevada to be observed directly. Much of the signal, in the range of 1 to 2 mm/yr, has been attributed to lithospheric scale rebound following massive groundwater withdrawal in the San Joaquin Valley in southern California, exacerbated by drought since 2011. However, natural tectonic deformation associated with long term uplift of the range may also contribute to the observed signal. We have developed new algorithms that enhance the signal of Sierra Nevada uplift and improve our ability to interpret and separate natural tectonic signals from anthropogenic contributions. We apply our new Median Interannual Difference Adjusted for Skewness (MIDAS) algorithm to the vertical times series and a inverse distance-weighted median spatial filtering and Delaunay-based interpolation to despeckle the rate map. The resulting spatially continuous vertical rate field is insensitive to outliers and steps in the GPS time series, and omits isolated features attributable to unstable stations or unrepresentative rates. The resulting vertical rate field for California and Nevada exhibits regionally coherent signals from the earthquake cycle including interseismic strain accumulation in Cascadia, postseismic relaxation of the mantle from recent large earthquakes in central Nevada and southern California, groundwater loading changes, and tectonic uplift of the Sierra Nevada and Coast Ranges. Uplift of the Sierra Nevada extends from the Garlock Fault in the south to an indefinite boundary in the north near the latitude of Mt. Lassen to the eastern Sierra Nevada range front in Owen's Valley. The rates transition to near zero in the southern Walker Lane. The eastern boundary of uplift coincides with the highest strain rates in the western Great Basin, suggesting higher normal fault slip rates and a component of tectonic uplift of the Sierra Nevada.

  2. Miracle Boy of Sierra Vista

    Institute of Scientific and Technical Information of China (English)

    Deborah; Morris; 郗莱仁

    1998-01-01

    Sierra Vista是美国亚利桑那州的一个偏僻的小镇。1990年11月12日,这里发生了一桩震惊全美的故事。 笔者的一位友人读罢此文,认为这是让人心跳的一场“劫后余生”。 文章的开头,展示了一幅温馨的家庭生活图: 11月12日这一天,正值美国的Veterans Day(退伍军人节),学校放假。Amanda,两个小孩的母亲,决定陪同她的朋友Lyne Jackson去Tucson,而她的两个小孩,Nicole,12岁,Justin,8岁,暂时由Lyne的父母照看。Nicole,Justin和Lyne的9岁的小孩Keith等一起在外面戏耍。 “劫难”的到来总是那么猝不及防: Suddenly, Keith burst inside. "Grandma, Justin’s hurt!" Keith spoke in a frightened, breathless voice,"Hurry!" 当祖母和Keith赶到出事现场时,见到的是一场惨祸; Justin was sprawled (四肢摊开躺着) on his back on the ground, his handsclutching(抓住) at a 5/8-inch-thick threaded steel rod(螺纹钢棒) buried deep in his stomach! 惨祸是如何发生的呢?原来: Justin and Keith had scaled(攀上) the magnolia (木兰树) ’s branches, then triedto leap onto the roof of the house. But Justin slipped on the shingles (屋顶板)and slidoff feet-first, plummeting (骤然跌下) 12 feet onto the

  3. The Special Court for Sierra Leone

    DEFF Research Database (Denmark)

    Damgaard, Ciara Therése

    2004-01-01

    The focus of this article is the Special Court for Sierra Leone and the extent to which it can be said that the Special Court has already challenged, or will, in the future, challenge the tradition of impunity for gender-based crimes. In this regard, an analysis is undertaken of the Special Court......'s Statute, Rules of Procedure and Evidence and practice to date, in order to determine its treatment of gender-based crimes and whether it can be said that the Special Court for Sierra Leone challenges the tradition of impunity for gender-based crimes. Udgivelsesdato: december 2004...

  4. NATURAL RESOURCE MANAGEMENT IN THE SIERRA OF SONORA UNDER THE SCHEME UMAFOR. CASE STUDY: SIERRA ALTA AND SIERRA LA MADERA

    Directory of Open Access Journals (Sweden)

    Hugo Silva-Kurumiya

    2011-05-01

    Full Text Available This paper shows the use and value of natural resources from a social, sustainable and legal perspective, under the scheme of Sustainable Forest Management Units (UMAFOR by its Spanish acronym. Two participatory workshops were carried out in March 2010, one in UMAFOR Sierra La Madera and another in UMAFOR Sierra Alta, belonging to the Sierra de Sonora. An adaptation of “Problems, Causes and Consequences” of Ramírez-García (2004 methodology was used to discuss issues such as conservation, productive activities, society, laws, research and support programs. The objective was to analyze challenges and opportunities in the Sierra de Sonora under this management scheme. The ratting of natural resource for inhabitant and producers was documented based in ecosystems type and its value for use. Economic value was the most important for productive and non productive use; however, there are opportunities to transit from traditional to sustainable activities. Local producers are interested in linking whit research centers and consultants to get support for diversification of productive activities. It is possible to have changes according to sustainable development; UMAFOR is an alternative to achieve those changes.

  5. Particularizing Universal Education in Postcolonial Sierra Leone

    Science.gov (United States)

    Pai, Grace

    2013-01-01

    This paper presents a vertical case study of the history of universalizing education in postcolonial Sierra Leone from the early 1950s to 1990 to highlight how there has never been a universal conception of universal education. In order to unite a nation behind a universal ideal of schooling, education needed to be adapted to different…

  6. Archaeological obsidian from La Sierra Gorda Mexico, by PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Juarez-Cossio, D.; Terreros, E.; Quiroz-Moreno, J.; Romero-Sanchez, S. [Instituto Nacional de Antropologia e Historia, Mexico. Seminario 8, Col. Centro. 06060 Mexico, DF (Mexico); Calligaro, T.F. [Centre de Recherche et de Restauration des Musees de France, UMR 171, Palais du Louvre-Porte des Lions, 14, Quai Francois Mitterrand, 75001 Paris (France); Tenorio, D. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico, DF (Mexico)], E-mail: dolores.tenorio@inin.gob.mx; Jimenez-Reyes, M. [Instituto Nacional de Investigaciones Nucleares, Apdo. Postal 18-1027, 11801 Mexico, DF (Mexico); Los Rios, M. de [Instituto Nacional de Antropologia e Historia, Mexico. Seminario 8, Col. Centro. 06060 Mexico, DF (Mexico)

    2009-04-15

    The chemical compositions of 42 obsidian pre-Hispanic artifacts from Tancama and Purisima, both archaeological sites of La Sierra Gorda Valleys, Mexico, were analyzed by PIXE technique. These obsidians came from four sources: Sierra de Pachuca Hidalgo, Paraiso Queretaro, Ucareo Michoacan and mainly from Zacualtipan/Metzquititlan Hidalgo. According to archaeological evidences, La Sierra Gorda valleys participated in commercial exchange with other regional sites, from Classic to Post-classic periods (A.D. 300-1500)

  7. SIERRA Toolkit v. 2.0

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-14

    The SIERRA Toolkit is a collection of libraries to facilitate the development of parallel engineering analysis applications. These libraries supply basic core services that an engineering application may need such as a parallel distributed and dynamic mesh database (for unstructured meshes), mechanics algorithm support (parallel infrastructure only), interfaces to parallel solvers, parallel mesh and data I/O, and various utilities (timers, diagnostic tools, etc.)

  8. La estructura del Grupo Sierras Bayas en el sector norte de las sierras homónimas, noroeste de las Sierras Septentrionales de Buenos Aires

    OpenAIRE

    A.C. Massabie; O.E. Nestiero

    2005-01-01

    El Grupo Sierras Bayas, de edad precámbrica tardía, se halla integrado por las formaciones sedimentarias Villa Mónica, Cerro Largo y Loma Negra, y forman parte de la porción noroccidental de las Sierras Septentrionales de Buenos Aires. Los afloramientos principales, relativamente aislados en serranías bajas, se ubican en los alrededores de Olavarría, particularmente en las Sierras Bayas, y con menor extensión en cercanías a la localidad de Barker. La morfoestructura de conjunto de estas sedim...

  9. 75 FR 76975 - 2015 Resource Pool-Sierra Nevada Region

    Science.gov (United States)

    2010-12-10

    ... Area Power Administration 2015 Resource Pool--Sierra Nevada Region AGENCY: Western Area Power Administration, DOE. ACTION: Notice of Final Power Allocations. SUMMARY: The Western Area Power Administration..., Western Area Power Administration, Sierra Nevada Customer Service Region, 114 Parkshore Drive, Folsom,...

  10. British Military Intervention into Sierra Leone: A Case Study

    Science.gov (United States)

    2007-12-14

    BRITISH MILITARY INTERVENTION INTO SIERRA LEONE : A CASE STUDY A thesis presented to the Faculty of the U.S. Army Command and...NUMBER 5b. GRANT NUMBER 4. TITLE AND SUBTITLE British Military Intervention into Sierra Leone : A Case Study 5c. PROGRAM ELEMENT NUMBER 5d...

  11. Indigenous Knowledge and Library Work in Sierra Leone

    Science.gov (United States)

    Kargbo, John Abdul

    2006-01-01

    Indigenous knowledge is vital information that is sadly diminishing at an alarming rate in Sierra Leone. There is, therefore, an urgent need to collect it before much of it is completely lost. This article explores the concept of indigenous knowledge and indigenous knowledge systems with a particular focus on Sierra Leone. Definitions and…

  12. Increased precipitation acidity in the central Sierra Nevada

    Science.gov (United States)

    Byron, Earl R.; Axler, Richard P.; Goldman, Charles R.

    Between 1979 and 1986, precipitation acidity increased significantly on the crest of the central Sierra Nevada. Variation in precipitation pH was closely associated with change in nitrate concentrations but not to sulfate. This area of the Sierra Nevada crest contains many acid-sensitive, poorly buffered lakes and ponds which can be adversely affected by increasing precipitation acidity.

  13. Archaeological obsidian from La Sierra Gorda Mexico, by PIXE

    Science.gov (United States)

    Juárez-Cossío, D.; Terreros, E.; Quiroz-Moreno, J.; Romero-Sánchez, S.; Calligaro, T. F.; Tenorio, D.; Jiménez-Reyes, M.; Rios, M. De Los

    2009-04-01

    The chemical compositions of 42 obsidian pre-Hispanic artifacts from Tancama and Purísima, both archaeological sites of La Sierra Gorda Valleys, México, were analyzed by PIXE technique. These obsidians came from four sources: Sierra de Pachuca Hidalgo, Paraíso Querétaro, Ucareo Michoacán and mainly from Zacualtipán/Metzquititlán Hidalgo. According to archaeological evidences, La Sierra Gorda valleys participated in commercial exchange with other regional sites, from Classic to Post-classic periods (A.D. 300-1500).

  14. Adhesive joint and composites modeling in SIERRA.

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Yuki; Brown, Arthur A.; Hammerand, Daniel Carl; Adolf, Douglas Brian; Chambers, Robert S.; Foulk, James W., III (.,; )

    2005-11-01

    Polymers and fiber-reinforced polymer matrix composites play an important role in many Defense Program applications. Recently an advanced nonlinear viscoelastic model for polymers has been developed and incorporated into ADAGIO, Sandia's SIERRA-based quasi-static analysis code. Standard linear elastic shell and continuum models for fiber-reinforced polymer-matrix composites have also been added to ADAGIO. This report details the use of these models for advanced adhesive joint and composites simulations carried out as part of an Advanced Simulation and Computing Advanced Deployment (ASC AD) project. More specifically, the thermo-mechanical response of an adhesive joint when loaded during repeated thermal cycling is simulated, the response of some composite rings under internal pressurization is calculated, and the performance of a composite container subjected to internal pressurization, thermal loading, and distributed mechanical loading is determined. Finally, general comparisons between the continuum and shell element approaches for modeling composites using ADAGIO are given.

  15. Post-Ebola Syndrome, Sierra Leone.

    Science.gov (United States)

    Scott, Janet T; Sesay, Foday R; Massaquoi, Thomas A; Idriss, Baimba R; Sahr, Foday; Semple, Malcolm G

    2016-04-01

    Thousands of persons have survived Ebola virus disease. Almost all survivors describe symptoms that persist or develop after hospital discharge. A cross-sectional survey of the symptoms of all survivors from the Ebola treatment unit (ETU) at 34th Regimental Military Hospital, Freetown, Sierra Leone (MH34), was conducted after discharge at their initial follow-up appointment within 3 weeks after their second negative PCR result. From its opening on December 1, 2014, through March 31, 2015, the MH34 ETU treated 84 persons (8-70 years of age) with PCR-confirmed Ebola virus disease, of whom 44 survived. Survivors reported musculoskeletal pain (70%), headache (48%), and ocular problems (14%). Those who reported headache had had lower admission cycle threshold Ebola PCR than did those who did not (pEbola syndrome. The Ebola epidemic is waning, but the effects of the disease will remain.

  16. Population size, survival, growth, and movements of Rana sierrae

    Science.gov (United States)

    Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A. W.; Halstead, Brian J.; Link, William

    2013-01-01

    Based on 2431 captures of 757 individual frogs over a 9-yr period, we found that the population of R. sierrae in one meadow–stream complex in Yosemite National Park ranged from an estimated 45 to 115 adult frogs. Rana sierrae at our relatively low elevation site (2200 m) grew at a fast rate (K = 0.73–0.78), had high overwintering survival rates (44.6–95%), lived a long time (up to 16 yr), and tended to be fairly sedentary during the summer (100% minimum convex polygon annual home ranges of 139 m2) but had low year-to-year site fidelity. Even though the amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) has been present in the population for at least 13 yr, there was no clear downward trend as might be expected from reports of R. sierrae population declines associated with Bd or from reports of widespread population decline of R. sierrae throughout its range.

  17. Initiatives for Sustainable Community Development in Sierra Leone.

    Science.gov (United States)

    Kamara, John M.; Kargbo, Stephen B.

    1999-01-01

    In Sierra Leone, two church-sponsored programs are focused on sustainable development. The Wesleyan Development Education and Awareness Programme trains people to initiate community projects. Women's Loan Scheme encourages development of small-scale enterprises. (SK)

  18. Functional Requirements for SIERRA Version 1.0 Beta

    Energy Technology Data Exchange (ETDEWEB)

    EDWARDS, HAROLD C.; STEWART, JAMES R.; TAYLOR, LEE M.

    1999-10-01

    The objective of the SIERRA framework is to provide a common software infrastructure for massively parallel computational mechanics applications. The SIERRA framework consolidates the mechanics-independent computational services required by a diverse set of mechanics applications into a shared framework. Consolidation of these computational services eliminates their redundant development and maintenance efforts and streamlines the coupling of independently developed computational mechanics capabilities into integrated multi-mechanics applications.

  19. International Marketing Strategy of Transformations LTD in Sierra Leone

    OpenAIRE

    Alam, Mohammed Touqeer

    2011-01-01

    The central idea of the report is to formulate an international marketing strategy for Transformations Ltd, a learning and development company based in UK for its entry in Sierra Leone market. The company wants to provide accredited British Leadership and Management qualification in Sierra Leone. The report uses theoretical framework for marketing analyses including internationalization models, entry mode, market segmentation, targeting, positioning and generic strategy. The report adopte...

  20. Sierra Structural Dynamics User's Notes

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Garth M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-19

    Sierra/SD provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. This document provides a users guide to the input for Sierra/SD. Details of input specifications for the different solution types, output options, element types and parameters are included. The appendices contain detailed examples, and instructions for running the software on parallel platforms.

  1. Political Economy of Extractives Governance in Sierra Leone

    OpenAIRE

    Fanthorpe, Richard; Gabelle, Christopher

    2013-01-01

    Sierra Leone is still recovering from a brutal civil war (1991-2002), fuelled in part by a valuable and easily extractable natural resource (diamonds). Sierra Leone now stands on the verge of an unprecedented period of economic growth, driven primarily by revenues from large-scale iron ore mining. Yet it continues to face many governance and developmental challenges. The rapid rise of the ...

  2. Contaminant studies in the Sierra Nevadas

    Science.gov (United States)

    Sparling, D.W.; Fellers, G.

    2002-01-01

    full text: Several species of anuran amphibians (frogs and toads) are experiencing severe population declines in even seemingly pristine areas of the Sierra Mountains of California. Among the most severely depressed species are the redlegged frog, the foothill and mountain yellow-legged frogs, the Yosemite toad, and the Cascades frog. Several factors, such as habitat fragmentation, introduced predators (especially fish), and disease, have been linked to these declines. But recent evidence from a USGS-led study shows that contaminants are a primary factor. During the past three years, researchers from the USGS Patuxent Wildlife Research Center, the Western Ecology Research Center, the USDA Beltsville Agriculture Research Center, and the Texas A&M University have teamed up to conduct an extensive study on airborne pesticides and their effects on amphibian populations in the Sierra Nevada Mountains. Previous work on environmental chemistry demonstrated that pesticides from the intensely agricultural Central Valley of California are being blown into the more pristine Sierra Nevada Mountains, especially around Sequoia and Yosemite National Parks. Several pesticides, including diazinon, chlorpyrifos, malathion and endosulfan, can be measured in snow, rainfall, and pond waters in these national parks. With the exception of endosulfan, these pesticides affect and even kill both invertebrates and vertebrate species by inhibiting cholinesterase, an enzyme essential to proper nervous system functioning. In the summer of 2001, we published a paper showing that these same pesticides are now found in adults and the tadpoles of Pacific treefrogs. The results of this landmark study showed that more than 50 percent of the tadpoles and adults sampled in Yosemite and Sequoia National Parks had detectable levels of diazinon or chlorpyrifos and that 86 percent of the Pacific treefrogs sampled in the Lake Tahoe region had detectable levels of endosulfan. In contrast, frogs that were

  3. 75 FR 44942 - 2015 Resource Pool-Sierra Nevada Customer Service Region

    Science.gov (United States)

    2010-07-30

    ... Nevada Customer Service Region AGENCY: Western Area Power Administration, DOE. ACTION: Notice of Proposed... Anderson, Power Marketing Manager, Sierra Nevada Customer Service Region, Western Area Power Administration... INFORMATION CONTACT: Ms. Sonja Anderson, Power Marketing Manager, Sierra Nevada Customer Service...

  4. Ammonia at Blodgett Forest, Sierra Nevada, USA

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Marc L.; Littlejohn, David

    2007-11-06

    Ammonia is a reactive trace gas that is emitted in large quantities by animal agriculture and other sources in California, which subsequently forms aerosol particulate matter, potentially affecting visibility, climate, and human health. We performed initial measurements of NH{sub 3} at the Blodgett Forest Research Station (BFRS) during a two week study in June, 2006. The site is used for ongoing air quality research and is a relatively low-background site in the foothills of the Sierra Nevada. Measured NH{sub 3} mixing ratios were quite low (< 1 to {approx} 2 ppb), contrasting with typical conditions in many parts of the Central Valley. Eddy covariance measurements showed NH{sub 3} fluxes that scaled with measured NH{sub 3} mixing ratio and calculated aerodynamic deposition velocity, suggesting dry deposition is a significant loss mechanism for atmospheric NH{sub 3} at BFRS. A simple model of NH{sub 3} transport to the site supports the hypothesis that NH{sub 3} is transported from the Valley to BFRS, but deposits on vegetation during the summer. Further work is necessary to determine whether the results obtained in this study can be generalized to other seasons.

  5. Deformación cuaternaria asociada al frente de levantamiento oriental de las sierras de Velasco y Ambato, Sierras Pampeanas occidentales Quaternary deformation associated with the eastern uplift front of the Sierras de Velasco and Ambato, western Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    Analía L. Casa

    2010-12-01

    Full Text Available Sobre el frente oriental de la sierra de Velasco y extremo sur de la sierra de Ambato, Sierras Pampeanas Occidentales, se han hallado nuevas evidencias de actividad tectónica cuaternaria en cercanías de la ciudad de La Rioja. Los rasgos reconocidos corresponden a distintos tramos reactivados de las fallas que delimitan los frentes serranos y a estructuras que afectan los depósitos cuaternarios sobre el piedemonte. la sierra de Velasco Oriental se encuentra marginada por fallas de rumbo NNE e inclinación al ONO, mientras que la sierra de Ambato austral presenta estructuras de rumbo NE que inclinan al NO. En el bloque Carrizal estas direcciones se interfieren originando un sector de mayor complejidad estructural. La deformación observada evidencia la persistencia de un régimen compresivo durante el Cuaternario al que se asocian fallas inversas de vergencia oriental a sudoriental. Estas fallas continúan elevando los cordones serranos y constituyen potenciales fuentes sismogénicas.Along the eastern front of the Sierra de Velasco and at the southern end of the Sierra de Ambato, western Sierras Pampeanas, have been found new evidences of Quaternary tectonic activity near La Rioja city. Observed evidences correspond to different reactivated sections of the faults that bound the mountain fronts, as well as to structures affecting the Quaternary deposits on the piedmont. The bounding faults of the Sierra de Velasco Oriental-front exhibit a NNE trend and WNW dip, while structures at the southernmost Ambato range are characterized by NE trend and NW dip. The neotectonic faults of the El Carrizal block are the result of the interference of both structural trends, resulting in a sector with higher structural complexity. The here described deformation show the persistence of a compressive regime during the Quaternary, with eastern to southeastern verging reverse faults. It is considering that these faults are driving the current uplift of the mountain

  6. Noteworthy records of two species of mammals in the Sierra Madre de Oaxaca, Mexico

    OpenAIRE

    2006-01-01

    We conducted mammal surveys in the Sierra Madre de Oaxaca (Sierra Norte) in Oaxaca, Mexico, and recorded the occurrence of two conspicuous mammal species: the spider monkey (Ateles geoffroyi vellerosus) and the coyote (Canis latrans cagottis). Spider monkeys has not been previously recorded in the Sierra Madre de Oaxaca, and coyotes have not been previously observed in Mexico at elevations as high as the present one (3 200 masl) in the Sierra Madre de Oaxaca

  7. La estructura del Grupo Sierras Bayas en el sector norte de las sierras homónimas, noroeste de las Sierras Septentrionales de Buenos Aires

    Directory of Open Access Journals (Sweden)

    A.C. Massabie

    2005-03-01

    Full Text Available El Grupo Sierras Bayas, de edad precámbrica tardía, se halla integrado por las formaciones sedimentarias Villa Mónica, Cerro Largo y Loma Negra, y forman parte de la porción noroccidental de las Sierras Septentrionales de Buenos Aires. Los afloramientos principales, relativamente aislados en serranías bajas, se ubican en los alrededores de Olavarría, particularmente en las Sierras Bayas, y con menor extensión en cercanías a la localidad de Barker. La morfoestructura de conjunto de estas sedimentitas en el sector norte de las Sierras Bayas corresponde a una cubeta asimétrica levemente basculada hacia el sudsudoeste. En el Grupo Sierras Bayas, se han identificado y relevado sistemáticamente dos sistemas de plegamiento suave F1 (NE y F2 (NO que se interfieren y generan diseños de tipo 1 en domos y cubetas. Los plegamientos reconocidos, F1 y F2, de planos axiales subverticales y ejes B subhorizontales se interfieren con ángulos que varían entre 70º y 90º. Desarrollan tres órdenes de plegamiento que controlan en las escalas adoptadas para el mapeo, la posición de los afloramientos y exposiciones artificiales de las formaciones integrantes del Grupo Sierras Bayas. El fallamiento local relevado ejerce un control muy limitado sobre la disposición de las sedimentitas precámbricas plegadas, y las observaciones de campo avalan su actividad inicial con posterioridad al episodio tectónico que desarrolló los sistemas de plegamiento del Grupo Sierras Bayas. La deformación dúctil de la cubierta sedimentaria, como ha sido observado localmente, se considera que ha estado asociada con una reactivación tectónica del basamento, Complejo Buenos Aires, favorecida por las anisotropías penetrativas principales preexistentes en el macizo rocoso de granititas milonitizadas. La similitud en el diseño de los plegamientos F1 y F2, la morfoestructura general en cubeta y la falta de una secuencia definida en las relaciones de interferencia permitir

  8. Nuevas evidencias de deformaciones cuaternarias asociadas a la falla Sierra chica, Sierras pampeanas de Córdoba

    Directory of Open Access Journals (Sweden)

    Guillermo L Sagripanti

    2012-12-01

    Full Text Available En la intraplaca argentina, entre los 31º 45' y 32º 45' de latitud S, en el frente occidental de la Sierra Chica, Sierras Pampeanas de Córdoba, la presencia de morfologías superficiales y deformaciones en sedimentos cuaternarios permiten deducir que la actividad tectónica neógena en la región, tuvo continuidad en el Holoceno y probablemente ha tenido asociada la ocurrencia de paleoterremotos. Los objetivos de la presente contribución son presentar nuevas evidencias de deformaciones cuaternarias asociadas a la falla Sierra Chica, extender su traza hacia el sur en la llanura y hacer una estimación preliminar del potencial sismogénico asociado a esta estructura. Se relevaron siete perfiles transversales a la traza de una falla secundaria del frente principal de levantamiento de la Sierra Chica. Estos presentan el basamento cristalino precámbrico, depósitos conglomerádicos y sedimentos no cohesivos cuaternarios, afectados por deformaciones dúctiles y frágiles correspondientes a reactivaciones pleistocenas y holocenas de la estructura. Los resultados obtenidos han permitido extender la traza de la falla hacia el S en la llanura hasta el arroyo Tegua, relevar estructuras deformacionales en sedimentos finos no reportadas hasta el presente y estimar la magnitud máxima de un terremoto futuro, entre Ms 6,7-7,5 y Mw=7,5, asociado a la falla Sierra Chica.

  9. SIERRA - A 3-D device simulator for reliability modeling

    Science.gov (United States)

    Chern, Jue-Hsien; Arledge, Lawrence A., Jr.; Yang, Ping; Maeda, John T.

    1989-05-01

    SIERRA is a three-dimensional general-purpose semiconductor-device simulation program which serves as a foundation for investigating integrated-circuit (IC) device and reliability issues. This program solves the Poisson and continuity equations in silicon under dc, transient, and small-signal conditions. Executing on a vector/parallel minisupercomputer, SIERRA utilizes a matrix solver which uses an incomplete LU (ILU) preconditioned conjugate gradient square (CGS, BCG) method. The ILU-CGS method provides a good compromise between memory size and convergence rate. The authors have observed a 5x to 7x speedup over standard direct methods in simulations of transient problems containing highly coupled Poisson and continuity equations such as those found in reliability-oriented simulations. The application of SIERRA to parasitic CMOS latchup and dynamic random-access memory single-event-upset studies is described.

  10. The geodynamic evolution of the eastern Sierras Pampeanas based on geochemical, Sm-Nd, Pb-Pb and SHRIMP data

    DEFF Research Database (Denmark)

    Drobe, M; Lopez de Luchi, M; Steenken, A;

    2011-01-01

    Whole-rock geochemical analyses using major and trace elements in combination with the Sm–Nd and Pb–Pb isotope systems, together with SHRIMP age dating on metasedimentary rocks from the Sierras de Chepes, the Sierras de Co´rdoba, the Sierra Norte and the San Luis Formation in the Sierra de San Luis...

  11. Ecología de la fauna silvestre de la sierra nevada y la Sierra del Ajusco

    OpenAIRE

    M. A. Hernández García; Sánchez González, A; D. Granados Sánchez; G. F. López Ríos

    2004-01-01

    Se presenta un estudio sobre la fauna silvestre de la Sierra del Ajusco y la Sierra Nevada, localizadas dentro de la Faja Volcánica Transmexicana (FVT), en la porción oriental del límite meridional de la Cuenca de México. La enorme riqueza biológica de esta zona que rodea la zona metropolitana de la ciudad de México, uno de los mayores complejos urbanos del mundo, ha sobrevivido durante décadas al impacto de la urbanización de las áreas forestales, explotación de recursos naturales, contamina...

  12. Sierra/solid mechanics 4.22 user's guide.

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Jesse David

    2011-10-01

    Sierra/SolidMechanics (Sierra/SM) is a Lagrangian, three-dimensional code for the analysis of solids and structures. It provides capabilities for explicit dynamic and implicit quasistatic and dynamic analyses. The explicit dynamics capabilities allow for the efficient and robust solution of models subjected to large, suddenly applied loads. For implicit problems, Sierra/SM uses a multi-level iterative solver, which enables it to effectively solve problems with large deformations, nonlinear material behavior, and contact. Sierra/SM has a versatile library of continuum and structural elements, and an extensive library of material models. The code is written for parallel computing environments, and it allows for scalable solutions of very large problems for both implicit and explicit analyses. It is built on the SIERRA Framework, which allows for coupling with other SIERRA mechanics codes. This document describes the functionality and input structure for Sierra/SM.

  13. An accidental sect: how war made belief in Sierra Leone

    NARCIS (Netherlands)

    Richards, P.

    2006-01-01

    Idealists consider beliefs cause wars. Realists consider wars cause beliefs. The war in Sierra Leone offers some scope to test between these two views. The main rebel faction, the Revolutionary United Front (RUF) was, sociologically speaking, an accidental sect. It lost its original ideologues at an

  14. Catastrophic rockfalls and rockslides in the Sierra Nevada, USA

    Science.gov (United States)

    Wieczorek, Gerald F.; Evans, Stephen G.; DeGraff, Jerome V.

    2002-01-01

    Despite having a low recorded historical incidence of landsliding, the Sierra Nevada has undergone large prehistoric and historical rockfalls and rockslides that could be potentially catastrophic if they occurred today in the more densely populated parts of the region. Several large documented rockfall and rockslides have been triggered either by strong seismic shaking or long periods of unusually wet weather; however, in several instances no obvious triggering event can be identified. The glaciated topography of the higher elevations of the SierraNevada has produced many relatively small falls and slides within relatively hard, massively jointed, granitic rocks; however, where exposed to weathering for long periods after glaciation, the oversteepened rock slopes are prone to uncommonly large falls and slides. At lower elevations on the nonglaciated slopes of the Sierra Nevada, rockslides commonly occur within more weathered granitic rocks, where the strength of the rock mass is typically affected by joint weathering and alteration of the intact rock to saprolite. Historical large rock-falls and rockslides in the Sierra Nevada have created additional secondary natural hazards, including debris flows and floods from the breaching of landslide dams that can be as hazardous as the initial rockfalls and rockslides.

  15. Library Education and the Practitioner: The Sierra Leone Experience.

    Science.gov (United States)

    Kargbo, John Abdul

    1999-01-01

    Examines the past and current educational trends of librarianship in Sierra Leone. Discuses courses offered in the current library school; economic and political issues affecting higher education; the need for full-time faculty; general versus specialized practitioner needs; attitudes of faculty toward working librarians; and professional…

  16. School-Based Peace Building in Sierra Leone

    Science.gov (United States)

    Bretherton, Diane; Weston, Jane; Zbar, Vic

    2005-01-01

    This article describes the development of a peace education project, including the Peace Education Kit, in schools in Sierra Leone. The program, initiated by the World Bank, has involved working partnerships between local and international agencies and provides a case study of how schools can work with the community to contribute to a national…

  17. Life in Sierra Leone, West Africa. A Teaching Unit.

    Science.gov (United States)

    Corby, Richard A.

    This unit is designed for students in grades 6-12. The unit provides an introduction to Sierra Leone and the continent of Africa through basic concepts and a conceptual framework for learning. The unit is divided into 17 activities. Activities include: (1) "Stereotypes and Myths about African and Africans"; (2) "The Manding Name…

  18. School Libraries in Sierra Leone's Educational System: Quo Vadis?

    Science.gov (United States)

    Kargbo, John A.

    2003-01-01

    Examines the role of school libraries in Sierra Leone's (Africa) educational system and the problems affecting their development. Discusses the need for materials to support teaching activities; sociological factors; teachers' and students' information needs; current trends and changes; rural areas with no school libraries; and lack of standards,…

  19. Power in Practice: Trade Union Education in Sierra Leone

    Science.gov (United States)

    Stirling, John

    2013-01-01

    This article presents an analysis of the development of a trade union education program in Sierra Leone in the geo-historical context of British colonialism. It places the argument in relation to the contradictory trends of trade unionism more generally and alongside their antagonistic cooperation with capitalism. It discusses the limits and…

  20. A New Agenda for Adult Education in Sierra Leone.

    Science.gov (United States)

    Skelt, Joanna

    2003-01-01

    After years of conflict, Sierra Leone has critical educational development needs including trauma healing and conflict resolution, rebuilding of the educational infrastructure, and citizenship and capacity building. Citizenship education in this context must be redefined as developing individual agency and encouraging active participation. (SK)

  1. The Sierra Club--A History. Part 2: Conservation

    Science.gov (United States)

    Strong, Douglas H.

    1977-01-01

    This second article on Sierra Club history brings the Club into the 1960s. It relates early conservation activities of the club, such as the efforts to save the Hetch Hetchy Valley. The campaign against construction of a dam in Dinosaur National Monument helped establish the club as a national organization. (MA)

  2. Health complications of female genital mutilation in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Bjälkander O

    2012-07-01

    Full Text Available Owolabi Bjälkander,1 Laurel Bangura,2 Bailah Leigh,3 Vanja Berggren,1 Staffan Bergström,1 Lars Almroth11Division of Global Health, Department of Public Health, Karolinska Institutet, Stockholm, Sweden; 2Inter Africa Committee, Sierra Leone; 3Department of Community Health, College of Medicine and Allied Health Sciences, University of Sierra Leone, Sierra LeoneAbstract: Sierra Leone has one of the highest rates of female genital mutilation (FGM in the world, and yet little is known about the health consequences of the practice.Purpose: To explore whether and what kind of FGM-related health complications girls and women in Sierra Leone experience, and to elucidate their health care-seeking behaviors.Patients and methods: A feasibility study was conducted to test and refine questionnaires and methods used for this study. Thereafter, a cross-section of girls and women (n = 258 attending antenatal care and Well Women Clinics in Bo Town, Bo District, in the southern region and in Makeni Town, Bombali District, in the northern region of Sierra Leone were randomly selected. Participants answered interview-administrated pretested structured questionnaires with open-ended-questions, administrated by trained female personnel.Results: All respondents had undergone FGM, most between 10 and 14 years of age. Complications were reported by 218 respondents (84.5%, the most common ones being excessive bleeding, delay in or incomplete healing, and tenderness. Fever was significantly more often reported by girls who had undergone FGM before 10 years of age compared with those who had undergone the procedure later. Out of those who reported complications, 187 (85.8% sought treatment, with 89 of them visiting a traditional healer, 75 a Sowei (traditional circumciser, and 16 a health professional.Conclusion: The high prevalence rate of FGM and the proportion of medical complications show that FGM is a matter for public health concern in Sierra Leone. Girls who

  3. Lassa fever in post-conflict sierra leone.

    Directory of Open Access Journals (Sweden)

    Jeffrey G Shaffer

    2014-03-01

    Full Text Available Lassa fever (LF, an often-fatal hemorrhagic disease caused by Lassa virus (LASV, is a major public health threat in West Africa. When the violent civil conflict in Sierra Leone (1991 to 2002 ended, an international consortium assisted in restoration of the LF program at Kenema Government Hospital (KGH in an area with the world's highest incidence of the disease.Clinical and laboratory records of patients presenting to the KGH Lassa Ward in the post-conflict period were organized electronically. Recombinant antigen-based LF immunoassays were used to assess LASV antigenemia and LASV-specific antibodies in patients who met criteria for suspected LF. KGH has been reestablished as a center for LF treatment and research, with over 500 suspected cases now presenting yearly. Higher case fatality rates (CFRs in LF patients were observed compared to studies conducted prior to the civil conflict. Different criteria for defining LF stages and differences in sensitivity of assays likely account for these differences. The highest incidence of LF in Sierra Leone was observed during the dry season. LF cases were observed in ten of Sierra Leone's thirteen districts, with numerous cases from outside the traditional endemic zone. Deaths in patients presenting with LASV antigenemia were skewed towards individuals less than 29 years of age. Women self-reporting as pregnant were significantly overrepresented among LASV antigenemic patients. The CFR of ribavirin-treated patients presenting early in acute infection was lower than in untreated subjects.Lassa fever remains a major public health threat in Sierra Leone. Outreach activities should expand because LF may be more widespread in Sierra Leone than previously recognized. Enhanced case finding to ensure rapid diagnosis and treatment is imperative to reduce mortality. Even with ribavirin treatment, there was a high rate of fatalities underscoring the need to develop more effective and/or supplemental treatments for

  4. Lassa Fever in Post-Conflict Sierra Leone

    Science.gov (United States)

    Hartnett, Jessica N.; Levy, Danielle C.; Yenni, Rachael E.; Moses, Lina M.; Fullah, Mohammed; Momoh, Mambo; Fonnie, Mbalu; Fonnie, Richard; Kanneh, Lansana; Koroma, Veronica J.; Kargbo, Kandeh; Ottomassathien, Darin; Muncy, Ivana J.; Jones, Abigail B.; Illick, Megan M.; Kulakosky, Peter C.; Haislip, Allyson M.; Bishop, Christopher M.; Elliot, Deborah H.; Brown, Bethany L.; Zhu, Hu; Hastie, Kathryn M.; Andersen, Kristian G.; Gire, Stephen K.; Tabrizi, Shervin; Tariyal, Ridhi; Stremlau, Mathew; Matschiner, Alex; Sampey, Darryl B.; Spence, Jennifer S.; Cross, Robert W.; Geisbert, Joan B.; Folarin, Onikepe A.; Happi, Christian T.; Pitts, Kelly R.; Geske, F. Jon; Geisbert, Thomas W.; Saphire, Erica Ollmann; Robinson, James E.; Wilson, Russell B.; Sabeti, Pardis C.; Henderson, Lee A.; Khan, S. Humarr; Bausch, Daniel G.; Branco, Luis M.; Garry, Robert F.

    2014-01-01

    Background Lassa fever (LF), an often-fatal hemorrhagic disease caused by Lassa virus (LASV), is a major public health threat in West Africa. When the violent civil conflict in Sierra Leone (1991 to 2002) ended, an international consortium assisted in restoration of the LF program at Kenema Government Hospital (KGH) in an area with the world's highest incidence of the disease. Methodology/Principal Findings Clinical and laboratory records of patients presenting to the KGH Lassa Ward in the post-conflict period were organized electronically. Recombinant antigen-based LF immunoassays were used to assess LASV antigenemia and LASV-specific antibodies in patients who met criteria for suspected LF. KGH has been reestablished as a center for LF treatment and research, with over 500 suspected cases now presenting yearly. Higher case fatality rates (CFRs) in LF patients were observed compared to studies conducted prior to the civil conflict. Different criteria for defining LF stages and differences in sensitivity of assays likely account for these differences. The highest incidence of LF in Sierra Leone was observed during the dry season. LF cases were observed in ten of Sierra Leone's thirteen districts, with numerous cases from outside the traditional endemic zone. Deaths in patients presenting with LASV antigenemia were skewed towards individuals less than 29 years of age. Women self-reporting as pregnant were significantly overrepresented among LASV antigenemic patients. The CFR of ribavirin-treated patients presenting early in acute infection was lower than in untreated subjects. Conclusions/Significance Lassa fever remains a major public health threat in Sierra Leone. Outreach activities should expand because LF may be more widespread in Sierra Leone than previously recognized. Enhanced case finding to ensure rapid diagnosis and treatment is imperative to reduce mortality. Even with ribavirin treatment, there was a high rate of fatalities underscoring the need to

  5. La estructura del Grupo Sierras Bayas en el sector norte de las sierras homónimas, noroeste de las Sierras Septentrionales de Buenos Aires The structure of Sierras Bayas Group in the north area of the homonymous hills, northwest of Sierras Septentrionales of Buenos Aires, Argentine

    OpenAIRE

    A.C. Massabie; O.E. Nestiero

    2005-01-01

    El Grupo Sierras Bayas, de edad precámbrica tardía, se halla integrado por las formaciones sedimentarias Villa Mónica, Cerro Largo y Loma Negra, y forman parte de la porción noroccidental de las Sierras Septentrionales de Buenos Aires. Los afloramientos principales, relativamente aislados en serranías bajas, se ubican en los alrededores de Olavarría, particularmente en las Sierras Bayas, y con menor extensión en cercanías a la localidad de Barker. La morfoestructura de conjunto de estas sedim...

  6. Rangewide glaciation in the Sierra Nevada, California

    Science.gov (United States)

    Moore, James G.; Moring, Barry C.

    2013-01-01

    The 600-km-long Sierra Nevada underwent extensive Pleistocene glaciation except for its southernmost 100 km. Presently, ∼1700 small glaciers and ice masses near the crest of the range occur above 3250 m in elevation; these covered an area of ∼50 km2 in 1972. Fourteen of the largest glaciers decreased by about one half in area during the period from 1900 to 2004. Rock glaciers, generally glacial ice covered by 1–10 m of rockfall debris, occur in about the same span of the range as ice and permanent snowfields. They are, on average, lower by 200–300 m, apparently because of the insulating layer of rocky rubble that protects their internal ice from the sun’s heat and from wind. The principal Pleistocene glacial stages are the Sherwin (ca. 820 ka), Tahoe (170–130 and ca. 70 ka), Tioga (14–28 ka), and Recess Peak (13 ka). Some 7040 glacial lakes, produced primarily by quarrying from bedrock, were mostly exposed after recession of the Tioga glacial stage. The lakes largely mark the area of primary snow accumulation. Below the lower limit of the lakes, ice flowed downward into river-cut canyons, forming major trunk glaciers within the zone of ablation. The range is in general a westward-tilted block upfaulted on its east side. Therefore, the main late Pleistocene trunk glaciers (Tahoe/Tioga) west of the crest extend 25–60 km, whereas those east of the crest extend only 5–20 km. Because of higher precipitation northward, glacial features such as the toes of existing glaciers and rock glaciers, as well as the late season present-day snowline, all decrease in elevation northward. Likewise, the elevation of the lower limit of glacial lakes, an indication of the zone of snow accumulation during the late Pleistocene, decreases about the same degree. This similarity suggests that the overall climate patterns of the late Pleistocene, though cooler, were similar to those of today. The east slope glaciers show a similar northward depression, but they are ∼500

  7. Impact breccias in carbonate rocks, Sierra Madera, Texas.

    Science.gov (United States)

    Wilshire, H. G.; Howard, K. A.; Offield, T. W.

    1971-01-01

    Two main types of deformational breccia occur in the Sierra Madera cryptoexplosion structure: monolithologic breccias composed of shattered rock of a single lithology and mixed breccias composed of rocks of several lithologies. Monolithologic breccias generally show no mineralogic signs of shock deformation, but a few samples are shatter-coned in a manner suggesting simultaneous formation of breccias and shatter cones. Mixed breccias, forming irregular, cross-cutting bodies, consistently contain moderately to highly shocked material, with mineralogic evidence of shock pressures of 50 kb to more than 200 kb, which, with evidence from the structural geometry of Sierra Madera and orientation of shatter cones, indicate an impact origin of the breccias. The mode of occurrence of the breccias, petrographic characteristics, and association with shock features are shared by breccias in many other cryptoexplosion structures in both carbonate and crystalline rock terranes, suggesting that such breccias have a common origin.

  8. Sequence variability and geographic distribution of Lassa virus, Sierra Leone.

    Science.gov (United States)

    Leski, Tomasz A; Stockelman, Michael G; Moses, Lina M; Park, Matthew; Stenger, David A; Ansumana, Rashid; Bausch, Daniel G; Lin, Baochuan

    2015-04-01

    Lassa virus (LASV) is endemic to parts of West Africa and causes highly fatal hemorrhagic fever. The multimammate rat (Mastomys natalensis) is the only known reservoir of LASV. Most human infections result from zoonotic transmission. The very diverse LASV genome has 4 major lineages associated with different geographic locations. We used reverse transcription PCR and resequencing microarrays to detect LASV in 41 of 214 samples from rodents captured at 8 locations in Sierra Leone. Phylogenetic analysis of partial sequences of nucleoprotein (NP), glycoprotein precursor (GPC), and polymerase (L) genes showed 5 separate clades within lineage IV of LASV in this country. The sequence diversity was higher than previously observed; mean diversity was 7.01% for nucleoprotein gene at the nucleotide level. These results may have major implications for designing diagnostic tests and therapeutic agents for LASV infections in Sierra Leone.

  9. Improving Critical Thinking "via" Authenticity: The CASPiE Research Experience in a Military Academy Chemistry Course

    Science.gov (United States)

    Chase, A. M.; Clancy, H. A.; Lachance, R. P.; Mathison, B. M.; Chiu, M. M.; Weaver, G. C.

    2017-01-01

    Course-based undergraduate research experiences (CUREs) can introduce many students to authentic research activities in a cost-effective manner. Past studies have shown that students who participated in CUREs report greater interest in chemistry, better data collection and analysis skills, and enhanced scientific reasoning compared to traditional…

  10. The Revolutionary United Front and Child Soldiers during Sierra Leone’s Civil War

    Science.gov (United States)

    2015-06-12

    amputations, torture, rape , and executions. Sierra Leone’s civil war is an interesting case study of how a rebel group could use a sizeable population...THE REVOLUTIONARY UNITED FRONT AND CHILD SOLDIERS DURING SIERRA LEONE’S CIVIL WAR A thesis presented to the Faculty of the...AND SUBTITLE The Revolutionary United Front and Child Soldiers during Sierra Leone’s Civil War 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  11. Foundering lithosphere imaged beneath the southern Sierra Nevada, California, USA.

    Science.gov (United States)

    Boyd, Oliver S; Jones, Craig H; Sheehan, Anne F

    2004-07-30

    Seismic tomography reveals garnet-rich crust and mantle lithosphere descending into the upper mantle beneath the southeastern Sierra Nevada. The descending lithosphere consists of two layers: an iron-rich eclogite above a magnesium-rich garnet peridotite. These results place descending eclogite above and east of high P wave speed material previously imaged beneath the southern Great Valley, suggesting a previously unsuspected coherence in the lithospheric removal process.

  12. Modelos de asentamiento en la sierra norte de Soria

    Directory of Open Access Journals (Sweden)

    Manuel CORRAL CAÑÓN

    2009-10-01

    Full Text Available En esta comunicación intentaremos una aproximación a las estructuras económicas y los modelos de asentamiento de los poblados de la Edad del Hierro en la Sierra norte de Soria. Nuestra intención es reconocer las diferencias entre los asentamientos del Hierro I y II, tanto en lo que refiere a las posibilidades del entorno, como a los esquemas de organización de los habitats.

  13. Promoting Mobile Financial Transactions : A Case Study Zain Sierra Leone

    OpenAIRE

    Atuyota-Ejughemre, Kesiena

    2009-01-01

    Title – Promoting Mobile Financial Transactions: A Case study of Zain Sierra Leone Author – Kesiena Atuyota-Ejughemre Supervisor - Anders Hederstierna Department: School of Management, Blekinge Institute of Technology Course: Master’s thesis in business administration, 15 credits (ECTS). Background and Problem Discussion: There are challenges associated with overly cash based societies. The use of mobile financial systems could address some of these challenges. Understanding the factors that ...

  14. Environmental values and risk: A review of Sierra Club policies

    Energy Technology Data Exchange (ETDEWEB)

    Craig, P.P. [Univ. of California, Davis, CA (United States). Graduate Group in Ecology

    1999-12-01

    Sierra Club values are driven by an overriding environmental ethic. Sierra Club environmental values may be characterized by the concept of 'usufruct' a term favored by United States Founding Father Thomas Jefferson. Usufruct conveys the idea that the environment is ours to use, but not to destroy. Each generation has the obligation to pass on to future generations a world at least as environmentally rich as the one it inherited. It is appropriate to accept risk today in order to preserve the environment for generations yet to come. As viewed through the lens of its formal policies, the Sierra Club is an organization that embraces technology, but insists that technology be evaluated comprehensively, taking full account of both environmental and social externalities. The Club is 'risk averse' with respect to early introduction of technologies seen as likely to have significant negative environmental or social impact. The Club places heavy emphasis on process, which must involve the public meaningfully.

  15. Attenuation Tomography of Sierra Negra Volcano of the Galapagos Archipelago

    Science.gov (United States)

    Rodd, R.; Lees, J. M.

    2014-12-01

    Following relocation of events with the double-difference location algorithm (HypoDD), we apply tomographic methods to extract 3D attenuation models illuminating the plumbing system of the Sierra Negra Caldera of the Galapagos Archipelago. The dataset consists of 1737 events recorded from July 2009 to June 2011 on the 17-station SIGNET broadband seismic array. We use t* spectral decay methods for both P- and S- phases with the clustered locations to highlight locations where significant variations in Q suggest the presence of magma melt. While the presence of a magma sill, at least 2 km depth, is indicated by InSAR and GPS studies, the delineated magma body has not been explored in detail. The lower bound of the proposed magma accumulation is still under question and thus forms the primary target of this research. Melt replenishment and degassing of the magma sill is believed to cause inflation and/or deflation of the caldera floor. Imaging the extent of the magma sill will provide insight into the feeder system and deformation process of the Sierra Negra caldera. Detailed relocation, Qp and Qs inversion, as well as estimates of the scattering attenuation using coda-normalization technique will be presented. The close relationship between seismic attenuation and the thermal state of the magmatic system suggests we can distinguish melt and/or fluid regions within the Sierra Negra plumbing system.

  16. Hydrocode modeling of the Sierra Madera impact structure

    Science.gov (United States)

    Goldin, Tamara J.; Wünnemann, Kai; Melosh, H. Jay; Collins, Gareth S.

    We present the first hydrocode simulations of the formation of the Sierra Madera structure (west Texas, USA), which was caused by an impact into a thick sedimentary target sequence. We modeled Sierra Madera using the iSALE hydrocode, and here we present two best-fit models: 1) a crater with a rim (final crater) diameter of ˜12 km, in agreement with previous authors' interpretations of the original structure, and 2) a crater ˜16 km in diameter with increased postimpact erosion. Both models fit some of the geologic observational data, but discrepancies with estimates of peak shock pressure, extent of deformation, and stratigraphic displacement remain. This study suggests that Sierra Madera may be a larger crater than previously reported and illustrates some of the challenges in simulating impact deformation of sedimentary lithologies. As many terrestrial craters possess some amount of sedimentary rocks in the target sequence, numerical models of impacts into sedimentary targets are essential to our understanding of target rock deformation and the mechanics of crater formation.

  17. La actividad neotectónica en la sierra Baja de San Marcos - Cruz del Eje, flanco occidental de las Sierras Pampeanas Orientales

    OpenAIRE

    A Massabie; A. Sanguinetti; G Lo Forte; M Cegarra

    2003-01-01

    El área pedemontana de San Marcos Sierra-Cruz del Eje constituye, en la provincia de Córdoba, Argentina, una comarca clave para el análisis neotectónico en las Sierras Pampeanas Orientales. En esta región se han realizado estudios centrados en la unidad morfoestructural sierra Baja de San Marcos donde, aplicando un control múltiple de datos estructurales, geomorfológicos, sedimentológicos, paleontológicos y radimétricos, se ha determinado temporal y espacialmente la evolución de la actividad ...

  18. Ebola Virus Diagnostics: The US Centers for Disease Control and Prevention Laboratory in Sierra Leone, August 2014 to March 2015.

    Science.gov (United States)

    Flint, Mike; Goodman, Christin H; Bearden, Scott; Blau, Dianna M; Amman, Brian R; Basile, Alison J; Belser, Jessica A; Bergeron, Éric; Bowen, Michael D; Brault, Aaron C; Campbell, Shelley; Chakrabarti, Ayan K; Dodd, Kimberly A; Erickson, Bobbie R; Freeman, Molly M; Gibbons, Aridth; Guerrero, Lisa W; Klena, John D; Lash, R Ryan; Lo, Michael K; McMullan, Laura K; Momoh, Gbetuwa; Massally, James L; Goba, Augustine; Paddock, Christopher D; Priestley, Rachael A; Pyle, Meredith; Rayfield, Mark; Russell, Brandy J; Salzer, Johanna S; Sanchez, Angela J; Schuh, Amy J; Sealy, Tara K; Steinau, Martin; Stoddard, Robyn A; Taboy, Céline; Turnsek, Maryann; Wang, David; Zemtsova, Galina E; Zivcec, Marko; Spiropoulou, Christina F; Ströher, Ute; Towner, Jonathan S; Nichol, Stuart T; Bird, Brian H

    2015-10-01

    In August 2014, the Viral Special Pathogens Branch of the US Centers for Disease Control and Prevention established a field laboratory in Sierra Leone in response to the ongoing Ebola virus outbreak. Through March 2015, this laboratory tested >12 000 specimens from throughout Sierra Leone. We describe the organization and procedures of the laboratory located in Bo, Sierra Leone.

  19. Assessment of Anemia Knowledge, Attitudes and Behaviors among Pregnant Women in Sierra Leone

    Science.gov (United States)

    M'Cormack, Fredanna A. D.; Drolet, Judy C.

    2012-01-01

    Introduction: Iron deficiency anemia prevalence of pregnant Sierra Leone women currently is reported to be 59.7%. Anemia is considered to be a direct cause of 3-7% of maternal deaths and an indirect cause of 20-40% of maternal deaths. This study explores knowledge, attitudes, and behaviors of urban pregnant Sierra Leone women regarding anemia.…

  20. Re-imaging the Modernity of Sierra Leone and Equatorial Guinea: Africa past and Africa present

    OpenAIRE

    Codling, Rosetta

    2011-01-01

    This paper engages the concept of the imposed Modernity of Europe upon the African republics of Sierra Leone and Equatorial Guinea. Evidence of the encroachment of a ‘false’ Modernity upon Africa’s Sierra Leone and Equatorial Guinea are chronicled in the works of Donato Ndongo (Shadows of Your Black Memory) and Syl Cheney Coker (The Last Harmattan of Alusine Dunbar).

  1. Non-Governmental Organizations in Africa: The Leonenet Street Children Project in Sierra Leone

    Science.gov (United States)

    Hinton, Samuel

    2005-01-01

    The purpose of this paper is to provide snapshots of observations, interventions, and processes in the day to day working of a child charity in Sierra Leone. There were 114 local and 49 overseas funded Non Governmental Organizations (NGOs) in Sierra Leone in 2002. The Leonenet Street Children Project was founded in 1996 by the membership of the…

  2. The Structure at Sierra Ambato, Catamarca, Argentina: A New Meteorite Impact Site?

    Science.gov (United States)

    Acevedo, R. D.; Rocca, M.; Alonso, R.; Rabassa, J.; Ponce, J. F.

    2012-09-01

    A new possible impact crater was discovered in Catamarca Province: the structure at Sierra Ambato (28º 03" 23.22” S, 66º 03" 11.06” W), located at Sierras Pampeanas (3,500 m.a.s.l). It has 1.0 km in diameter.

  3. Cretaceous stratigraphy and biostratigraphy, Sierra Blanca basin, southeastern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, S.G. (New Mexico Museum of Natural History, Albuquerque, NM (United States)); Anderson, O.R. (New Mexico Bureau of Mines Mineral Resources, Socorro, NM (United States))

    1994-03-01

    The Sierra Blanca basin of Otero and Lincoln counties, New Mexico contains a Lower (upper Albian)-Upper (Santonian) Cretaceous section of marine and nonmarine strata as much as 700 m thick which represent the upper part of a regressive cycle followed by two transgressive-regressive deposition cycles. The lower 55 m of the Cretaceous section are the same tripartite Dakota Group units recognized in Guadalupe and San Miguel counties: basal Mesa Rica Sandstone (late Albian), medial Pajarito formation (late Albian) and upper Romeroville sandstone (earliest Cenomanian). The Mesa Rica and Pajarito represent a regression and are overlain disconformably by the transgressive Romeroville sandstone. Overlying transgressive marine clastics and minor carbonates of the Mancos Shale are as much as 73 m thick and include the early Turonian Greenhorn Limestone. The overlying Tres Hermanos formation (up to 91 m thick) consists of the (ascending order) Atarque sandstone and the Carthage and Fite Ranch sandstone members. These strata represent a mid-Turonian regression in response to regional tectonism (Atarque and Carthage), followed by a transgression (Fite Ranch sandstone) that ended in the deposition of the D-Cross Tongue of the Mancos Shale and Fort Hays Member of the Niobrara Formation during the late Turonian. The subsequent regression began with the Coniacian Gallup Sandstone (55 m) followed by coal-bearing Crevasse Canyon Formation (up to 244 m thick). The Coniacian-Santonian Crevasse Canyon Formation, the youngest Cretaceous unit in the basin, is disconformably overlain by middle Eocene conglomerates and red-bed siliciclastics of the Cub Mountain formation. Dakota Group age determinations in the Sierra Blanca basin are those of well-dated sections to the north, but ammonites and inoceramid bivalves from the Sierra Blanca basin provide precise age control for Cenomanian-Santonian marine and marginal marine strata and palynology and megafossil plants for nonmarine strata.

  4. Agrarian change and labour migration in the Sierra of Ecuador.

    Science.gov (United States)

    Peek, P

    1980-01-01

    "Among the effects produced in the Sierra of Ecuador by the programme of land reforms launched in 1964 was a reduction in the incomes from small-scale farming. At the same time, the growth of productive employment in urban areas was insufficient to provide round-the-year work to the fast growing army of jobseekers. Analysis of the agrarian structure and migration patterns before and after 1964 suggests that it was primarily this combination of circumstances that produced a pronounced shift towards short-term rather than permanent migration, thereby providing industry and services with the labour they needed while avoiding the disadvantages of severe urban overpopulation."

  5. Sierra Leone After the War : Reconstruction, Aid and Corruption

    OpenAIRE

    Camara, Pa Musa

    2012-01-01

    Investors have stayed away from the African continent for a very long time and rightfully so. The continent is fraught with civil unrest from Somalia to Sudan, from Libya to Democratic Republic of Congo. Most of the countries that are experiencing civil unrests are resource-rich nations. This gives credence to the concept of ‘resource curse’ for resource-rich nations. Sierra Leone is no exception, having suffered an eleven-year long civil war, from 1991 to 2002, causing major setbacks for the...

  6. Dos nuevas inscripciones latinas de Elche de la Sierra (Albacete

    Directory of Open Access Journals (Sweden)

    Julián Francisco MARTÍN RUIZ

    2009-12-01

    Full Text Available Apareció la lápida al sitio llamado «El Mojón», en el término municipal de Elche de la Sierra, a unos dos kilómetros del núcleo principal de población y bastante más cerca —seiscientos metros aproximadamente— de una aldea dependiente de éste, conocida en la actualidad con el nombre de Villares y en la antigüedad con el de Gutar.

  7. PROBLEMS IN THE ADMISSION TO HIGHER EDUCATION IN THE LOWER SIERRA DE SONORA, CASE: UNIVERSITY OF SIERRA

    Directory of Open Access Journals (Sweden)

    Rubén Ángel Vásquez-Navarro

    2011-05-01

    Full Text Available The aim of this paper is to clarify the issues and find solutions to align somewhat academic models of institutions of higher average level and above found in the central highlands of the state of Sonora, as are the University of Sierra, and the CBTA 53 and confront the culture of the people of the importance of young people studying a degree in that region.The above educational institutions are located in the geographical catchment area and education, in fact, in the same population, in the northeastern state of Sonora. The mountains of Sonora had always intended to have a school of higher education. To justify the town of Montezuma as a geographically strategic point, and thanks to the efforts made by the governor in turn was as the University of Sierra opens its doors to students on the mountain in August 2002.For the analysis of the functioning of an educational institution in the rural sector, should take into account a wide range of factors, however, this work will be key to analyze the dislocation and inconsistency of educational models from an institution of higher average level in relationship to another level, which serve as a unique educational opportunities for the people of Sonora and surrounding Montezuma. In addition, the cultural aspect, which reflects a regional behavior of the inhabitants of the region. La Sierra University is located in the mountainous region of the state of Sonora, in the town of Montezuma, with a catchment area of more than 30 municipalities in this area, which lacked a college until recently time.

  8. Los granitos peraluminosos de las Sierras de Vinquis, Cerro Negro y Zapata (Sierras Pampeanas, provincia de Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Medina, M. E.

    1992-12-01

    Full Text Available The studied plutons are close to several batholiths of this region, as Sierra de Mazán and other, but with some mineralogical peculiarities. The magmatic cordierite, common in proximate places, is scarce, as sillimanite, while the andalusite is very rare, with few tourmaline. Fluorite and allanite are also typical accasories only in the granites of the Sierra de Zapata. All plutons are peraluminous of potassic tendency, with cortical affinity.The interpretation of the geochemical values distinguishes between granites of different maturity, emplaced under a predominant influence of active margin for Cerro Negro and Vinquis, while the batholith of Zapata has, below these concepts, a marked feature of within plate.The mineralogical associations suggest that the granites of Cerro Negro and Vinquis were emplaced to pressures of 2 kb or less and temperature of 650º C, while the granites of Zapata had done under conditions of lesser pressure, between 1.5 and 2.0 kb and lower temperature, 600-650º C.A grandes rasgos, los plutones estudiados tienen semejanzas con otros del entorno regional, tal como los de la Sierra de Mazán, pero con peculiaridades mineralógicas. La cordierita magmática, que en lugares próximos es muy abundante, es aquí escasa, al igual que la sillimanita, mientras que la andalucita es muy rara y la turmalina poco frecuente. La fluorita y allanita son accesorios comunes y de cierta abundancia sólo en los granitos de la Sierra de Zapata.Todos los plutones son peralumínicos y de tendencia potásica, con neta afinidad cortical. El estudio estadístico de datos geoquímicos seleccionados, permite diferenciar agrupaciones que tienen un reflejo satisfactorio en los plutones caracterizados, por encima de las variaciones de facies. La interpretación de los valores geoquímicos distingue granitos de desigual madurez, emplazados bajo una influencia predominante de margen activo o intraplaca de características continentales, en

  9. Active tectonics in the Argentine Precordillera and Western Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    L.L. Siame

    2006-12-01

    Full Text Available The Andean foreland of western Argentina (28°S-33°S corresponds to retroarc deformations associated with the ongoing flat subduction of the Nazca plate beneath the South American lithosphere. This region is characterized by high levels of seismic activity and crustal active faulting. To improve earthquake source identification and characterization in the San Juan region, data from seismology, structural geology and quantitative geomorphology were integrated and combined to provide a seismotectonic model. In this seismotectonic model, the Andean back-arc of western Argentina can be regarded as an obliquely converging foreland where Plio-Quaternary deformations are partitioned between strike-slip and thrust motions that are localized on the E-verging, thin-skinned Argentine Precordillera, and the W-verging thick-skinned Sierras Pampeanas, respectively. In this seismotectonic model, the Sierra Pie de Palo appears to be a key structure playing a major role in the partitioning of the Plio-Quaternary deformations.

  10. Juan Carandell Pericay (1893-1937 y Sierra Nevada

    Directory of Open Access Journals (Sweden)

    Antonio López Ontiveros

    2000-01-01

    Full Text Available Juan Carandell Pericay (1893-1937, geólogo y geógrafo ligado a la Institución Libre de Enseñanza, escribió unos trescientos títulos, con una actividad científica e intelectual muy polifacética: geología, geografía física, humana y regional, libros de viaje y excursiones pedagógicas, semiología gráfica, divulgación científica y otras actividades intelectuales y artísticas. Una parte significativa de dichas obras estuvo dedicada a las Béticas, en general, y a Sierra Nevada en particular. Aspectos considerados por Carandell sobre Sierra Nevada son los relativos a su geología, geomorfología y tectónica, la erosión y sus causas físicas y humanas, la geografía humana –con especial importancia para el tema del hábitat– y otra variada gama de temas entre los que merece mención la faceta de las representaciones del paisaje, en todas las cuales demostró no sólo sus sólidos conocimientos geológicos y geográficos, sino incluso una calidad artística más que apreciable.

  11. Sierra Nevada Rock Glaciers: Biodiversity Refugia in a Warming World?

    Science.gov (United States)

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

    2007-12-01

    Rock glaciers and related periglacial rock-ice features (RIFs) are common landforms in high, dry mountain ranges, and widely distributed throughout canyons of the Sierra Nevada, California, USA (Millar & Westfall, in press). Due to insulating rock carapaces, active rock glaciers (ice-cored) have been documented to maintain ice longer, and thus contribute to more enduring hydrologic output, under past warming climates than typical ice glaciers. This function has been suggested for the coming century. We propose a broader hydrologic and ecologic role for RIFs as temperatures rise in the future. For the Sierra Nevada, we suggest that canyons with either active or relict RIFs (Holocene and Pleistocene) maintain water longer and distribute water more broadly than canyons that were scoured by ice glaciers and are defined by primary river and lake systems. RIFs provide persistent, distributed water for extensive wetland habitat, rare in these otherwise barren, high, and dry locations. We mapped and assessed the area of wetlands surrounding active and relict RIFs from the central eastern Sierra Nevada; from these we delineated wetland vegetation community types and recorded plant species found in RIF-supported wetlands. Mid-elevation RIFs, likely inactive or with transient ice, develop soil patches on their rock matrix. At the Barney Rock Glacier (Duck Pass, Mammoth Crest), we inventoried plant species on all soil patches, and measured cover for each species per patch and total plant cover for the rock glacier. RIF landforms also appear to support high-elevation mammals. We show that American beaver (Castor canadensis) is associated with canyons dominated by active or relict RIFs and propose that the articulating, persistent, and distributed nature of streams makes dam-building easier than other canyons. Beavers further contribute to maintaining water and creating wetland habitat in upper watersheds by engineering ponds and marshes, and contributing to riparian extent. We

  12. Summary of the geology of the northern part of the Sierra Cuchillo, Socorroand Sierra Counties, southwestern New Mexico

    Science.gov (United States)

    Maldonado, Florian; Edited by Lucas, Spencer G.; McLemore, Virginia T.; Lueth, Virgil W.; Spielmann, Justin A.; Krainer, Karl

    2012-01-01

    The northern part of the Sierra Cuchillo is located within the northeastern part of the Mogollon-Datil volcanic field west of the Rio Grande rift in the Basin and Range Province, approximately 50 km northwest of Truth or Consequences in south-central New Mexico. The Sierra Cuchillo is a north-south, elongated horst block composed of Tertiary volcanic and intrusive rocks, sparse outcrops of Lower Permian and Upper Cretaceous rocks, and sediments of the Tertiary-Quaternary Santa Fe Group. The horst is composed mainly of a basal volcanic rock sequence of andesite-latite lava flows and mud-flow breccias with a 40Ar/39Ar isotopic age of about 38 Ma. The sequence is locally intruded by numerous dikes and plugs that range in composition from basaltic andesite through rhyolite and granite. The andesite-latite sequence is overlain by ash-flow tuffs and a complex of rhyolitic lava flows and domes. Some of these units are locally derived and some are outflow sheets derived from calderas in the San Mateo Mountains, northeast of the study area. These locally derived units and outflow sheets range in age from 28 to 24 Ma.

  13. Maintenance Support of a Field Station in Sierra Leone, West Africa

    Science.gov (United States)

    1994-03-04

    AD-A279 136 ARMY PROJECT ORDER NO: 91PP1801 TITLE: MAINTENANCE SUPPORT OF A FIELD STATION IN SIERRA LEONE , WEST AFRICA PRINCIPAL INVESTIGATOR: Brian...SUBTITLE S. FUNDING NUMBERS Maintenance Support of a Field Station in Army Project Order Sierra Leone , West Africa 91PP1801 6. AUTHOR(S) Brian W.J. Mahy...Detrick Frederick, Maryland 21702-5012 11. SUPPLEMENTARY NOTES Subtitle: Maintenance Support of a FiLd Station in Sierra Leone , West Africa for Lassa

  14. Culex Verutus, a New Species of the Subgenus Culex (Diptera: Culicidae) from Sierra Leone

    Science.gov (United States)

    1986-01-01

    216 Cu7ex verutus, a new species of the subgenu s1 Cu7ex (Diptera: Culicidae) from Sierra Leone Ralph E. Harbach’ Walter Reed Biosystematics...sp. from Sierra Leone are described and illus- trated. The new species is compared to other members of the guiarti group. This paper describes a...new species of Cu7ex collected in Sierra Leone by Dr. Yiau-Min Huang and Mr. James Pecor during field studies conducted in 1984. The species has been

  15. La actividad neotectónica en la sierra Baja de San Marcos - Cruz del Eje, flanco occidental de las Sierras Pampeanas Orientales Neotectonic activity in the Sierra Baja de San Marcos-Cruz del Eje area, west flank of Sierras Pampeanas Orientales

    OpenAIRE

    A Massabie; A. Sanguinetti; G Lo Forte; M Cegarra

    2003-01-01

    El área pedemontana de San Marcos Sierra-Cruz del Eje constituye, en la provincia de Córdoba, Argentina, una comarca clave para el análisis neotectónico en las Sierras Pampeanas Orientales. En esta región se han realizado estudios centrados en la unidad morfoestructural sierra Baja de San Marcos donde, aplicando un control múltiple de datos estructurales, geomorfológicos, sedimentológicos, paleontológicos y radimétricos, se ha determinado temporal y espacialmente la evolución de la actividad ...

  16. [The indigenous population of Sierra Norte de Puebla].

    Science.gov (United States)

    Marquez Gonzalez, G

    1991-06-01

    The northern sierra region of Pueblo, Mexico, contains 1496 communities in 65 municipios and covers 1/4 of the area of the state of Puebla. The topography is steep and mountainous, and the area is inaccessible. The region contains the 3 principal zones of Mesoamerica, hot lands from sea level to 700 meters above sea level, temperate zones from 700-1500 meters, and cold country from 1500-2000 meters above sea level. Most of the population resides in the temperate and cold lands, but the hot zones are economically important. Little is known of the prehistory of the area. The Totonac were believed to have been the earliest settlers. In the mid-15th century numerous Nahua groups came to the area. In the late 15th century the region fell to the Aztecs, but their dominion was cut short by the arrival of the Spanish. Spanish penetration was relatively slow because of the difficult terrain and the lack of precious metals desired by the Spanish. The introduction of coffee cultivation in the late 19th century accelerated the adoption of urban-mestizo sociocultural and commercial elements by the indigenous population. The population of the northern sierra increased from 752,656 in 1980 to 965,976 in 1990. The 1980 census reported that 259,140 persons spoke indigenous languages, including 179,677 who spoke Nahuatl, 66,020 Totonaco, and 4921 Otomi. The most important cities are located on paved roads: Teziutland, Zacatlan, Hauachinango, and Zacapoaxtla. The municipios with predominantly monolingual indigenous populations are concentrated in the most difficult to reach areas of the central sierra massif. The region is characterized by temporary and permanent emigration of the indigenous population. The main reasons for emigration are lack of land and of alternative sources of employment, and desire for education. During the months August-December, known as the time of hunger, there is seasonal migration of household heads in search of work as laborers in cane cutting, tobacco

  17. Botanical novelties from Sierra de Maigualida, southern Venezuela. II

    Directory of Open Access Journals (Sweden)

    Grande, José R.

    2012-06-01

    Full Text Available Four new species, Siphocampylus acanthidiotrichus J.R. Grande (Campanulaceae, Phyllanthus huberi Riina & P.E. Berry (Phyllanthaceae, Sohnreyia maigualidensis J.R. Grande & Kallunki (Rutaceae, and Turnera maigualidensis J.R. Grande & Arbo (Turneraceae are described and illustrated from the summit areas of Sierra de Maigualida in the Gua - yana Highlands of southern Venezuela. To date, one genus, 32 spe cies, one subspecies, and one variety of angiosperms are known only from the Maigualida meadows and shrublands, between 1800 m and the highest elevation areas at 2400 m. Here we describe the first iteroparous species for the genus Sohnreyia K. Krause, a Turnera L. species with apically villose, apiculate petals, and a Siphocampylus Pohl species with aculeiform hairs and pinnatisect leaves. The new species, Siphocampylus acanthidiotrichus, together with S. Tillettii Steyerm., represents a morphologically distinct subgroup within the genus.

    Se describen e ilustran cuatro especies nuevas procedentes de las cumbres de la Sierra de Maigualida: Siphocampylus acanthidiotrichus J.R. Grande (Campanulaceae, Phyllanthus huberi Riina & P.E. Berry (Phyllanthaceae, Sohnreyia maigualidensis J.R. Grande & Kallunki (Rutaceae y Turnera maigualidensis J.R. Grande & Arbo (Turneraceae. Hasta ahora un género, 32 especies, una subespecie y una variedad de angiospermas se conocen exclusivamente de la Sierra de Maigualida, y todas ellas proceden de herbazales y arbustales desarrollados entre los 1800 m y las áreas más altas, a 2400 m. Aquí, se describen por primera vez una especie iterópara del género Sohnreyia K. Krause (Rutaceae, una especie de Turnera L. con pétalos apiculados apicalmente vilosos y una especie de Siphocampylus Pohl con pelos aculeiformes y hojas pinnatisectas. La nueva especie Siphocampylus acanthidiotrichus representa

  18. Deformación cuaternaria asociada al frente de levantamiento oriental de las sierras de Velasco y Ambato, Sierras Pampeanas occidentales

    Directory of Open Access Journals (Sweden)

    Analía L. Casa

    2010-12-01

    Full Text Available Sobre el frente oriental de la sierra de Velasco y extremo sur de la sierra de Ambato, Sierras Pampeanas Occidentales, se han hallado nuevas evidencias de actividad tectónica cuaternaria en cercanías de la ciudad de La Rioja. Los rasgos reconocidos corresponden a distintos tramos reactivados de las fallas que delimitan los frentes serranos y a estructuras que afectan los depósitos cuaternarios sobre el piedemonte. la sierra de Velasco Oriental se encuentra marginada por fallas de rumbo NNE e inclinación al ONO, mientras que la sierra de Ambato austral presenta estructuras de rumbo NE que inclinan al NO. En el bloque Carrizal estas direcciones se interfieren originando un sector de mayor complejidad estructural. La deformación observada evidencia la persistencia de un régimen compresivo durante el Cuaternario al que se asocian fallas inversas de vergencia oriental a sudoriental. Estas fallas continúan elevando los cordones serranos y constituyen potenciales fuentes sismogénicas.

  19. DNA sequences of troglobitic nicoletiid insects support Sierra de El Abra and the Sierra de Guatemala as a single biogeographical area: Implications for Astyanax

    Directory of Open Access Journals (Sweden)

    Luis Espinasa

    2014-03-01

    Full Text Available The blind Mexican tetra fish, Astyanax mexicanus, has become the most influential model for research of cave adapted organisms. Many authors assume that the Sierra de Guatemala populations and the Sierra de El Abra populations are derived from two independent colonizations. This assumption arises in part from biogeography. The 100 m high, 100 m wide Servilleta Canyon of the Boquillas River separates both mountain ranges and is an apparent barrier for troglobite dispersion. Anelpistina quinterensis (Nicoletiidae, Zygentoma, Insecta is one of the most troglomorphic nicoletiid silverfish insects ever described. 16S rRNA sequences support that this species migrated underground to reach both mountain ranges within less than 12,000 years. Furthermore, literature shows a plethora of aquatic and terrestrial cave restricted species that inhabit both mountain ranges. Thus, the Servilleta canyon has not been an effective biological barrier that prevented underground migration of troglobites between the Sierra de Guatemala and the Sierra de El Abra. The Boquillas River has changed its course throughout time. Caves that in the past connected the two Sierras were only recently geologically truncated by the erosion of the new river course. It is likely that, with the geological changes of the area and throughout the 2-8 million years of evolutionary history of cave Astyanax, there have been opportunities to migrate across the Servilleta canyon.

  20. Element Verification and Comparison in Sierra/Solid Mechanics Problems

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Yuki; Roth, William

    2016-05-01

    The goal of this project was to study the effects of element selection on the Sierra/SM solutions to five common solid mechanics problems. A total of nine element formulations were used for each problem. The models were run multiple times with varying spatial and temporal discretization in order to ensure convergence. The first four problems have been compared to analytical solutions, and all numerical results were found to be sufficiently accurate. The penetration problem was found to have a high mesh dependence in terms of element type, mesh discretization, and meshing scheme. Also, the time to solution is shown for each problem in order to facilitate element selection when computer resources are limited.

  1. Enteric fever in a British soldier from Sierra Leone.

    Science.gov (United States)

    Osborne, Lucy G; Brown, M; Bailey, M S

    2016-06-01

    Enteric fever (typhoid and paratyphoid) remains a threat to British troops overseas and causes significant morbidity and mortality. We report the case of a soldier who developed typhoid despite appropriate vaccination and field hygiene measures, which began 23 days after returning from a deployment in Sierra Leone. The incubation period was longer than average, symptoms started 2 days after stopping doxycycline for malaria chemoprophylaxis and initial blood cultures were negative. The Salmonella enterica serovar Typhi eventually isolated was resistant to amoxicillin, co-amoxiclav, co-trimoxazole and nalidixic acid and had reduced susceptibility to ciprofloxacin. He was successfully treated with ceftriaxone followed by azithromycin, but 1 month later he remained fatigued and unable to work. The clinical and laboratory features of enteric fever are non-specific and the diagnosis should be considered in troops returning from an endemic area with a febrile illness. Multiple blood cultures and referral to a specialist unit may be required.

  2. Enfermedad y pobreza en la Sierra de Chiapas

    Directory of Open Access Journals (Sweden)

    Eugenia Bayona Escat

    2011-07-01

    Full Text Available Este artículo indaga en la desigualdad y exclusión social que padece la población de la región Sierra, Chiapas, en el ámbito de la salud, desde los testimonios de mujeres rurales que ofrecen su visión de la salud, la enfermedad y la atención sanitaria, y desarrollan estrategias para afrontar las dificultades. Se pretende demostrar cómo en un medio adverso, caracterizado por la pobreza y olvido institucional, los trastornos físicos son reiterativos, se convierten en incurables y contribuyen a la reproducción de la marginalidad. Así, se genera la enfermedad de la pobreza, que somatiza males físicos para expresar las carencias sociales.

  3. Calibration of a modified Sierra Model 235 slotted cascade impactor

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, R.H.

    1979-07-01

    For measurements of ore dust in uranium concentrating mills, a Sierra Model 235 slotted cascade impactor was calibrated at a flow rate of .21 m/sup 3//min, using solid monodisperse particles and an impaction surface of Whatman No. 41 filter paper soaked in mineral oil. The reduction from the impactor's design flow rate of 1.13 m/sup 3//min (40 cfm) to 0.21 m/sup 3//min (7.5 cfm) increased the stage cut-off diameters by an average factor of 2.3, a necessary adjustment because of the anticipated large particle sizes of ore dust. The underestimation of mass median diameters, often caused by the rebound and reentrainment of solid particles from dry impaction surfaces, was virtually eliminated by using the oiled Whatman No. 41 impaction surface. Observations of satisfactory performance in the laboratory were verified by tests of the impactor in ore mills.

  4. Ebola Virus Disease in Children, Sierra Leone, 2014–2015

    Science.gov (United States)

    Naveed, Asad; Wing, Kevin; Gbessay, Musa; Ross, J.C.G.; Checchi, Francesco; Youkee, Daniel; Jalloh, Mohammed Boie; Baion, David; Mustapha, Ayeshatu; Jah, Hawanatu; Lako, Sandra; Oza, Shefali; Boufkhed, Sabah; Feury, Reynold; Bielicki, Julia A.; Gibb, Diana M.; Klein, Nigel; Sahr, Foday; Yeung, Shunmay

    2016-01-01

    Little is known about potentially modifiable factors in Ebola virus disease in children. We undertook a retrospective cohort study of children Ebola holding units in the Western Area, Sierra Leone, during 2014–2015 to identify factors affecting outcome. Primary outcome was death or discharge after transfer to Ebola treatment centers. All 309 Ebola virus–positive children 2 days–12 years old were included; outcomes were available for 282 (91%). Case-fatality was 57%, and 55% of deaths occurred in Ebola holding units. Blood test results showed hypoglycemia and hepatic/renal dysfunction. Death occurred swiftly (median 3 days after admission) and was associated with younger age and diarrhea. Despite triangulation of information from multiple sources, data availability was limited, and we identified no modifiable factors substantially affecting death. In future Ebola virus disease epidemics, robust, rapid data collection is vital to determine effectiveness of interventions for children. PMID:27649367

  5. Geologic studies in the Sierra de Pena Blanca, Chihuahua, Mexico

    Science.gov (United States)

    Reyes-Cortes, Ignacio Alfonso

    The Sierra del Cuervo has been endowed with uranium mineralization, which has attracted many geological studies, and recently the author was part of a team with the goal of selecting a site of a radioactive waste repository. The first part of the work adds to the regional framework of stratigraphy and tectonics of the area. It includes the idea of a pull apart basin development, which justifies the local great thickness of the Cuervo Formation. It includes the regional structural frame work and the composite stratigraphic column of the Chihuahua Trough and the equivalent Cretaceous Mexican Sea. The general geologic features of the NE part of the Sierra del Cuervo are described, which include the folded ignimbrites and limestones in that area; the irregular large thicknesses of the Cuervo Formation; and the western vergence of the main folding within the area. Sanidine phenocrystals gave ages of 54.2 Ma and 51.8 Ma ± 2.3 Ma. This is the first time these dates have been reported in print. This age indicates a time before the folded structures which outcrop in the area, and 44 Ma is a date after the Cuervo Formation was folded. The Hidalgoan orogeny cycle affected the rocks between this lapse of time. Since then the area has been partially affected by three tensional overlapped stages, which resulted in the actual Basin and Range physiography. The jarosite related to the tectonic activity mineralization has been dated by the Ar-Ar method and yields an age of 9.8 Ma. This is the first report of a date of mineralization timing at Pena Blanca Uranium District in the Sierra del Cuervo. These are some of the frame work features that justify the allocation of a radioactive waste repository in the Sierra del Cuervo. An alluvial fan system within the Boquilla Colorada microbasin was selected as the best target for more detailed site assessment. The study also included the measurement of the alluvium thicknesses by geoelectric soundings; studies of petrography and weathered

  6. Los recursos humanos en un espacio natural protegido: Sierra Nevada

    Directory of Open Access Journals (Sweden)

    Ma. Enriqueta Cózar

    2000-01-01

    Full Text Available Sierra Nevada, como todas las áreas de montaña españolas y gran parte del territorio interior andaluz, ha experimentado durante el siglo XX un considerable retroceso demográfico. La población con la que llega al umbral del siglo XXI es una cuarta parte más pequeña que la registrada en 1900 y un tercio inferior a la de 1950. Diversos y complejos factores, tanto internos como externos al área de montaña, de carácter más económico que demográfico, fueron los desencadenantes de una fuerte emigración. La gran pérdida de población ha originado cambios trascendentales en la demografía y en la actividad económica de Sierra Nevada. En la actualidad, la población de este espacio protegido se caracteriza por una desequilibrada distribución en el territorio, un escaso crecimiento natural, un acelerado envejecimiento y una actividad mayoritariamente terciaria. La declaración, en Julio de 1989, como espacio natural protegido bajo la figura de Parque Natural, y la más reciente de Parque Nacional, apenas ha modificado la inercia demográfica regresiva de la mayor parte de sus municipios; tan sólo se ha podido apreciar una cierta tendencia a la estabilización demográfica de la población total del macizo

  7. The paleoenvironment of the "Sierra de la Primavera

    Science.gov (United States)

    Maciel, R.; Peña, L.; Rosas, J.

    2009-04-01

    The paleoenvironment of the "Sierra de la Primavera" (SP) Jalisco Mexico, was studied with paleontology, tephrachronology, strato-tectonic, geochronology and climatology techniques. It was created between 126,000 and 27,000 years ago (late Pleistocene) by more than 22 domes and a caldera (110 +- 15 thousand years). There are fault and fractures with a NNE and NNW trends, with up of four reactivation periods. Historically, seismic events have been registered around the caldera. Volcanic and tectonic activities have contributed to the modification of the morphology. The evidence of an intermittent paleolake formed into the caldera, are 24 strata are built on tephras, fluvial and vulcano-lacustres deposits, (> 51 m thick), present 2o to 35o leanings. The central part of the paleolake has raised more than 149 m which was caused by the reappearance of the magmatic chamber, it and the climatic changes disappeared the paleolake. There are layers of gigantic pomez and strata with carbon whith remaining from pines (ones, aciculas and branches). The method of 14C used in fossils report an age of 38,170 to 39,000 years BP. They are classified as remainings of Pinus durangensis Martínez, Pinus leiophylla Schiede ex Schltdl. & Cham., Pinus montezumae Lamb., Pinus luzmariae Pérez de la Rosa, Pinus teocote Schltdl. & Cham.y Pinus douglasiana Martínez. This community of pines was moved of SP to the Sierra de Bolaños (SB), 177 km northeast and 850 m higher (25000 masl), it is climatologically more humid and colder than the SP. This implies a movement in the border of the vegetation, associated to global climatic changes. Using the community of pines like bioindicator, it is inferred that the temperature in the SP has increased from 2 to 3 C and the precipitation has decreased between 100 and 200 mm from the late Pleistocene on. The predominant pine wood of its early years is now pine - Encino.

  8. Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis californiana)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas designated as critical habitat for the Sierra Nevada Bighorn Sheep. Critical habitat for the species occurs in twelve units: Mount...

  9. 76 FR 44535 - Revisions to the California State Implementation Plan, Northern Sierra Air Quality Management...

    Science.gov (United States)

    2011-07-26

    ... Management District, Sacramento Metropolitan Air Quality Management District, and South Coast Air Quality... proposing to approve revisions to the Northern Sierra Air Quality Management District (NSAQMD), Sacramento Metropolitan Air Quality Management District (SMAQMD), and South Coast Air Quality Management District......

  10. 76 FR 44493 - Revisions to the California State Implementation Plan, Northern Sierra Air Quality Management...

    Science.gov (United States)

    2011-07-26

    ... Management District, Sacramento Metropolitan Air Quality Management District, and South Coast Air Quality... taking direct final action to approve revisions to the Northern Sierra Air Quality Management District (NSAQMD), Sacramento Metropolitan Air Quality Management District (SMAQMD), and South Coast Air...

  11. Notes from The Field: Ebola Virus Disease Cluster - Northern Sierra Leone, January 2016.

    Science.gov (United States)

    Alpren, Charles; Sloan, Michelle; Boegler, Karen A; Martin, Daniel W; Ervin, Elizabeth; Washburn, Faith; Rickert, Regan; Singh, Tushar; Redd, John T

    2016-07-08

    On January 14, 2016, the Sierra Leone Ministry of Health and Sanitation was notified that a buccal swab collected on January 12 from a deceased female aged 22 years (patient A) in Tonkolili District had tested positive for Ebola virus by reverse transcription-polymerase chain reaction (RT-PCR). The most recent case of Ebola virus disease (Ebola) in Sierra Leone had been reported 4 months earlier on September 13, 2015 (1), and the World Health Organization had declared the end of Ebola virus transmission in Sierra Leone on November 7, 2015 (2). The Government of Sierra Leone launched a response to prevent further transmission of Ebola virus by identifying contacts of the decedent and monitoring them for Ebola signs and symptoms, ensuring timely treatment for anyone with Ebola, and conducting an epidemiologic investigation to identify the source of infection.

  12. Management of rice seed during insurgency : a case study in Sierra Leone

    NARCIS (Netherlands)

    Mokuwa, G.A.

    2015-01-01

    Keywords: Technography, Oryza glaberrima,  Oryza sativa, farmer hybrids, sub-optimal agriculture, farmer adaptive management, plant genetic resources, peace and extreme (wartime) conditions, local seed channels, selection for robustness, Sierra Leone, West Africa. Abstract Moku

  13. X-Ray Diffraction Powder Patterns and Thin Section Observations from the Sierra Madera Impact Structure

    Science.gov (United States)

    Huson, S. A.; Foit, F. F.; Watkinson, A. J.; Pope, M. C.

    2006-03-01

    X-Ray powder diffraction analysis and thin section observations of carbonate and siliciclastic samples from the Sierra Madera impact structure indicate moderate shock pressures (8 to 30 GPa) were generated during the formation of this crater.

  14. An investigation into the new emerging social sub group of professional Muslim women in Sierra Leone

    OpenAIRE

    Taqi, Fatmatta, B.

    2010-01-01

    Sierra Leone is in transition to peace and development, from a previous decade long civil war. Educated Muslim women appear to have a great deal of expression, interest and passion to offer the process. The study investigates the new emerging social sub group of professional Muslim women in Sierra Leone society and explores their views and experiences of identifying and attempting to overcome the burdens of patriarchy, oppression and exploitation perpetrated by religious, social and cultural ...

  15. Anomalías del campo gravitatorio y magnético terrestre en la sierra de Socoscora, provincia de San Luis Earth gravity and magnetic field anomalies in the Sierra of Socoscora, San Luis province

    Directory of Open Access Journals (Sweden)

    J Kostadinoff

    2003-12-01

    Full Text Available La sierra de Socoscora se ubica en forma meridiana y se manifiesta como un escalón al noroeste de la Sierra Grande de San Luis. En la sierra de Socoscora las rocas del basamento están representadas por metamorfitas de alto grado con escasos afloramientos de metabasitas. Las mediciones del campo gravitatorio y magnético indican la presencia de un volumen mayor de estas rocas en su subsuelo. Los excesos de masa en esta sierra se hallan definidas por anomalías gravimétricas de Bouguer (residuales positivas similares a las encontradas en la Sierra Grande de San Luis. La magnetometría indica, a partir de las respuestas positivas, la existencia de rocas máficas con concentraciones anómalas de minerales magnéticos.The Sierra de Socoscora is a north - south trending mountain range, located nortwest of the Sierra Grande of San Luis. The basament is constituted by high grade metamorphic rocks with few associated metabasites. Earth gravity and magnetic field measurements are indicative of the presence of bigger volumes of mafic rocks below the surface, which carry anomalous concentrations of ferromagnetic and/or paramagnetic minerals (magnetite and/or sulfides. An excess of mass below this Sierra is shown by Bouguer gravimetric anomalies with magnitudes similar to those measured in the Sierra Grande de San Luis. Positive magnetic anomalies are indicative of the presence of mafic rocks with anomalous concentrations of magnetic minerals.

  16. Transitioning from a U.N. Observer Mission to a Robust Peacekeeping Operation: Lessons from Sierra Leone

    Science.gov (United States)

    2007-11-02

    U.N.CHAPTER VI OBSERVER MISSION TO A ROBUST PEACEKEEPING OPERATION: LESSONS FROM SIERRA LEONE 9. Personal Authors: Peter V. Londono, CIV 10.Type of...necessarily endorsed by the NWC or the Department of the Navy. 14. Ten key words that relate to your paper: Peacekeeping, U.N., Sierra Leone , UNOMSIL...UNAMSIL, RUF, Peace Enforcement, Operation Relief Focus, ECOWAS, ECOMOG 15.Abstract: U.N. peacekeeping operations in Sierra Leone have special

  17. Late Paleozoic deformation and exhumation in the Sierras Pampeanas (Argentina): 40Ar/39Ar-feldspar dating constraints

    Science.gov (United States)

    Löbens, Stefan; Oriolo, Sebastián; Benowitz, Jeff; Wemmer, Klaus; Layer, Paul; Siegesmund, Siegfried

    2016-09-01

    Systematic 40Ar/39Ar feldspar data obtained from the Sierras Pampeanas are presented, filling the gap between available high- (>~300 °C) and low-temperature (Pie de Palo regions, whereas the Sierras de San Luis and the Sierra de Comechingones regions record exhumation during the Carboniferous. Comparison between new and available data points to a Carboniferous tectonic event in the Sierras Pampeanas, which represents a key period to constrain the early evolution of the proto-Andean margin of Gondwana. This event was probably transtensional and played a major role during the evolution of the Paganzo Basin as well as during the emplacement of alkaline magmatism in the retroarc.

  18. Sierra Elvira limestone: petrophysical characteristics of an Andalusian heritage stone

    Directory of Open Access Journals (Sweden)

    Valverde, I.

    2008-06-01

    Full Text Available “Sierra Elvira stone” is one of the ornamental building stones most widely used in the historical monuments of eastern Andalusia. A Liassic age limestone, it appears in the central section of the Baetic Mountains and more specifically in the Middle Subbaetic domain. While the most common variety is a crinoid limestone, a micritic limestone of the same age has also been quarried, albeit in much smaller quantities. These stones form very thick beds, up to nearly 5 m deep, that run in consistently parallel lines and have a dip angle that facilitates quarrying.With petrographic, physical and mechanical properties that ensure stone strength and durability, it is a high quality building material suitable for both structural and ornamental purposes. These properties can be attributed to the minimal open porosity and concomitant excellent water resistance that characterize the stone, as well as to its high mechanical strength and low textural anisotropy, both elastic and mechanical. With such attributes, the stone can be successfully used for any number of purposes, including decorative stonework (portals, fountains, plinths, structural members (column shafts and bases or urban curbing and paving. Intervention on Sierra de Elvira limestone structures should be limited to cleaning or repair, for consolidating or protective materials are scantly effective.La “Piedra de Sierra Elvira” constituye una de las piedras ornamentales más significativas del Patrimonio Arquitectónico de Andalucía Oriental. Es una roca caliza del Lias que aflora en el Subbético Medio del sector central de las Cordilleras Béticas. El litotipo más explotado es una caliza con crinoides, en bastante menor importancia se ha extraído también otra caliza micrítica de la misma edad. Los bancos son muy potentes, en algunos casos de más de 5 m, con un paralelismo constante y un buzamiento que favorece su explotación en los frentes de cantera.Sus caracter

  19. Monitoring lichens diversity and climatic change in Sierra Nevada (Spain

    Directory of Open Access Journals (Sweden)

    Fernández Calzado, M.ª R.

    2013-12-01

    Full Text Available Lichens are common organisms in high mountain zones, where they play an important role in ecosystem balance. In recent years, the increasing interest in understanding more about their interactions with abiotic factors has prompted several investigations, some of which have proved their value as bioindicators of climatic conditions. In this context, focusing on climatic change effects on high mountain vascular plants and supported by the Global Observation Research Initiative in Alpine Environments project (GLORIA, we have monitored for the first time the lichens biodiversity in Sierra Nevada with the intention of studying the alterations caused by the process of climatic change. The aim of this paper is to explain the monitoring experience developed on the massif and contribute to the first results from the biodiversity and statistical analysis of the sampling data.Los líquenes son organismos comunes en las zonas de alta montaña donde juegan un importante papel en el equilibrio de los ecosistemas. En los últimos años, el creciente interés por entender más acerca de sus interacciones con los factores abióticos ha motivado diversas investigaciones, algunas de las cuales han demostrado su valor como bioindicadores de las condiciones climáticas. En este contexto, centrándonos en los efectos del cambio climático en plantas vasculares de alta montaña y respaldados por el proyecto “Iniciativa para la investigación y el seguimiento global de los ambientes alpinos (GLORIA”, se ha monitorizado por primera vez la diversidad de líquenes en Sierra Nevada con la intención de estudiar las posibles alteraciones que esta pueda sufrir causadas por el proceso de cambio climático. El objetivo de este artículo es el de dar a conocer la experiencia de seguimiento en el macizo y aportar los primeros resultados procedentes del análisis, tanto de la biodiversidad como estadístico, de los datos de muestreo.

  20. East-west thrusting and anomalous magnetic declinations in the Sierra Gorda, Betic Cordillera, southern Spain

    Science.gov (United States)

    Platzman, E. S.

    1994-01-01

    Structural and palaeomagnetic studies in the Sierra Gorda (Sierra de Loja), located in the External zone of the Betic Cordillera, indicate that westward-directed thrusting is not associated with significant rotations about a vertical axis. Detailed mapping and slip vector analysis show that the Sierra Gorda is a thrust complex composed of three thrust sheets. The uppermost thrust places Early Jurassic pelagic carbonates on top of Jurassic to Oligocene sediments that form a large doubly-plunging footwall syncline. The eastern limb of this syncline has been overturned and is tectonically thinned as a result of the overthrusting. Palaeomagnetic results from Mesozoic and Tertiary sediments both within and around the perimeter of the Sierra Gorda indicate that: (1) the average remanence vector of the seven Late Jurassic localities sampled within the Sierra Gorda has a direction (D = 328° and I = 38°) that is not significantly different from the expected declination for the Upper Jurassic of stable Iberia; and (2) there is no significant difference between the remanences in the two upper thrust sheets indicating that differential rotation did not occur during the initiation and displacement on the thrusts. In contrast, the one Late Jurassic site that was sampled to the west of the Sierra Gorda is rotated, like the rest of the Subbetics, 60° clockwise of the reference direction. The unrotated directions obtained in the Sierra suggest, either that it has rotated in a clockwise sense concordant with the rest of the Subbetic zone and has then been backrotated, or that it has never rotated relative to stable Iberia. In the latter, simpler hypothesis the unrotated declinations may be explained in terms of orthogonal convergence along an irregular continental margin.

  1. Deformation of the late Miocene to Pliocene Inyo Surface, eastern Sierra region, California

    Science.gov (United States)

    Jayko, A.S.

    2009-01-01

    A middle and late Miocene erosion surface, the Inyo Surface, underlies late Miocene mafic flows in the White Mountains and late Miocene and (or) early Pliocene flows elsewhere in the eastern Sierra region. The Inyo Surface is correlated with an erosion surface that underlies late Miocene mafic flows in the central and northern Sierra Nevada. The mafic flows had outpourings similar to flood basalts, although of smaller volume, providing paleohorizontal and paleolowland indicators. The flows filed and locally topped the existing landscape forming broad plateau-like flats. Topographic relief in the region was characterized by weathered and rounded slopesp rior to late Miocene mafic magmatism. Relicts of the older landscape lie adjacent to late Miocene and early Pliocene basalt-covered lowlands that now occur within the crests of ranges that have 2500-3000 m relief and dramatically steep escarpments. Late Miocene mafic flows that lie on the crest of the Sierra Nevada adjacent to the White Mountains predate significant activity on the Sierra Nevada frontal fault zone. These deposits and accompanying erosion surfaces provide excellent strain markers for reconstructing part of the Walker Lane north of the Garlock fault and west of the Amargosa drainage, here referred to as the eastern Sierra region. The Inyo Surface is a compound erosional surface that records at least four major erosion events during the Cenozoic. These four surfaces were first recognized on the Kern Plateau and named from oldest to youngest, the Summit Upland, the Subsummit Plateau, the Chagoopa Plateau, and the Canyon. The three older surfaces have also been subsequently modifi ed by Pleistocene glaciation. The compound erosion surface, which is locally overlain by late Miocene mafic flows in the northern and central Sierra Nevada, is here referred to as the Lindgren Surface. Correlatives in the eastern Sierra region are found in the White Mountains, Inyo Mountains, Darwin Plateau, Coso Range, and

  2. El castillo de Penna Cadiella en la sierra de Benicadell

    Directory of Open Access Journals (Sweden)

    Navarro Oltra, Vicente Carlos

    2002-12-01

    Full Text Available In this article we try to locate the place where the castle of Penna Cadiella, mentioned in the Poem of Mio Cid could had been built. To this we reintroduce the hypothesis expressed in its time by P. Guichard regarding the castle's location on top of the Benicadell range of mountains (Valencia-Alicante and we provide new documentary and archaeological data. Likewise, we analyse the 371st chapter of Jaime I´s Crónica in which the battle fought for the possession of the above-mentioned castle by the troops of the Aragonese king against al-Azraq in the thirteenth century is narrated.

    En este trabajo se intenta localizar el lugar en el que pudo asentarse el castillo de Penna Cadiella mencionado en el Poema de Mío Cid. Para ello, se retoma la hipótesis que en su día planteara P. Guichard sobre su ubicación en la cima de la Sierra de Benicadell (Valencia-Alicante y se aportan nuevos datos documentales y arqueológicos. Asimismo, se analiza el capítulo 371 de la Crónica de Jaime I en el cual se relata la batalla que, por su posesión, libraron las tropas del rey aragonés contra al-Azraq a mediados del siglo XIII.

  3. Transverse fold evolution in the External Sierra, southern Pyrenees, Spain

    Science.gov (United States)

    Anastasio, David J.; Holl, James E.

    2001-02-01

    Fault-slip data are used to reconstruct varying tectonic regimes associated with transverse fold development along the eastern and southern margins of the Jaca basin, southern Pyrenees, Spain. The Spanish Pyrenean foreland consists of thrust sheets and leading-edge décollement folds which developed within piggyback basins. Guara Formation limestones on the margins of the Jaca basin were deposited synchronously with deformation and are exposed in the External Sierra. Within the transverse folds, principal shortening axes determined from P and T dihedra plots of fault-slip data show a shift from steep shortening in stratigraphically older beds to NNE-SSW horizontal shortening in younger beds. Older strata are characterized by extensional faults interpreted to result from halotectonic (salt tectonics) deformation, whereas younger strata are characterized by contraction and strike-slip faults interpreted to result from thrust sheet emplacement. The interpretation of the timing for the shortening axes in the younger strata is supported by the observation that these axes are parallel to shortening axes determined from finite strain analysis, calcite twins, and regional thrusting directions determined from fault-related folds and slickenlines. This study shows that fault population analysis in syntectonic strata provides an opportunity to constrain kinematic evolution during orogeny.

  4. específico en la sierra norte de Sevilla

    Directory of Open Access Journals (Sweden)

    Rafael Garzón García

    2008-01-01

    Full Text Available La primera parte del artículo ofrece una visión panorámica de la política de fomento del uso público en la Red de Espacios Naturales Protegidos de Andalucía desde su origen hasta nuestros días, con especial incidencia en cuestiones tales como el papel preponderante asumido por la figura de Parque Natural, el desequilibrio territorial de las intervenciones planteadas, o la necesaria ordenación y planificación de la actividad. Ello conforma el contexto idóneo para abordar, en segunda instancia, un análisis particularizado de la gestión del uso público en el Parque Natural Sierra Norte de Sevilla. La elección de este ámbito territorial se fundamenta tanto en sus especiales condicionantes para el fomento de esta línea de acción (privilegiada situación, existencia de una demanda tradicional asociada a determinados enclaves, propiedad de la tierra… como en la singular gestión desarrollada desde la declaración del parque, destacando las nuevas perspectivas e incertidumbres que parecen despertarse a partir del impulso y aprobación de una planificación específica

  5. Striving for excellence: nurturing midwives' skills in Freetown, Sierra Leone.

    Science.gov (United States)

    Ngongo, Carrie; Christie, Kate; Holden, Jude; Ford, Carolyn; Pett, Celia

    2013-10-01

    Midwives provide critical, life-saving care to women and babies. Effective midwives must be clinically competent, with the required knowledge, skills, and attitudes to provide quality care. Their success depends on an environment of supportive supervision, continuing education, enabling policies, and access to equipment and referral facilities. In Freetown, Sierra Leone, the Aberdeen Women's Centre launched a maternity unit with an emphasis on striving for excellence and providing ongoing professional development to its staff midwives. Its success was built upon fostering a sense of responsibility and teamwork, providing necessary resources, conforming to evidence-based standards, and building partnerships. An explicit philosophy of care was crucial for guiding clinical decision making. In its first two years of operation, the Aberdeen Women's Centre assisted 2076 births with two maternal deaths and 92 perinatal deaths. In-service education and supportive supervision facilitated the midwives' professional growth, leading to capable future leaders who are providing exemplary care to delivering mothers and their newborns in Freetown.

  6. Straining: Young Men Working through Waithood in Freetown, Sierra Leone

    Directory of Open Access Journals (Sweden)

    Brandon Finn

    2015-01-01

    Full Text Available Young men in precarious situations of persistent un(deremployment in post-civil war Freetown, Sierra Leone are depicted in popular and policy debate as “stuck” economically or “dangerous” and prone to violence. In the present paper, by contrast, we draw on young men’s explanations of their work and livelihood struggles as “straining.” We explore the logic of straining, its innovations and demands, and its geography across the city, especially where acts of straining interface with the prohibition and criminalisation of informal trading. We argue that straining innovates and endures because of (not despite young men’s marginalisation and limited autonomy and power. In this context, young men build forms of provisional agency and enact dynamic forms of waithood, in their strategies to earn a living to try to support their families and to negotiate a transition from youth to manhood. Drawing on this research, we argue for a more complex understanding of young men at work in Freetown, in particular, and of the “youth bulge,” in general, in African cities.

  7. California spotted owls: Chapter 5 in Managing Sierra Nevada forests

    Science.gov (United States)

    Roberts, Suzanne C.; Brooks, Matthew L.

    2012-01-01

    California spotted owls (Strix occidentalis occidentalis) are habitat specialists that are strongly associated with late-successional forests. For nesting and roosting, they require large trees and snags embedded in a stand with a complex forest structure (Blakesley et al. 2005, Gutiérrez et al. 1992, Verner et al. 1992b). In mixedconifer forests of the Sierra Nevada, California spotted owls typically nest and roost in stands with high canopy closure (≥75 percent) [Note: when citing studies, we use terminology consistent with Jennings et al. (1999), however, not all studies properly distinguish between canopy cover and closure and often use the terms interchangeably (see chapter 14 for clarification)] and an abundance of large trees (>24 in (60 cm) diameter at breast height [d.b.h.]) (Bias and Gutiérrez 1992, Gutiérrez et al. 1992, LaHaye et al. 1997, Moen and Gutiérrez 1997, Verner et al. 1992a). The California spotted owl guidelines (Verner et al. 1992b) effectively summarized much of the information about nesting and roosting habitat. Since that report, research on the California spotted owl has continued with much of the new information concentrated in five areas: population trends, barred owl (Strix varia) invasion, climate effects, foraging habitat, and owl response to fire.

  8. accidentes y otras causas violentas en la sierra de Sonora

    Directory of Open Access Journals (Sweden)

    Héctor Eloy Rivas Sánchez

    2005-01-01

    Full Text Available Este artículo presenta los resultados de una investigación sociológica cuyo objeto fue explorar el papel que ha jugado el modelo hegemónico de masculinidad en la ocurrencia de muertes derivadas de accidentes y varias formas de ejercicio de la violencia en una comunidad rural de la sierra de Sonora. Estos resultados difieren de aquellos que tradicionalmente los estudios de las masculinidades han mostrado para México y América Latina. El modelo dominante de masculinidad en las comunidades estudiadas no ha condicionado significativamente la ocurrencia de las muertes por accidentes y otras causas violentas. La responsabilidad, la disciplina y el respeto hacia las personas consideradas socialmente débiles (mujeres, ancianos y niños, principalmente son características que debe poseer un hombre de verdad en las comunidades estudiadas. El apego de los hombres a estas formas de comportamiento y su temor a perder honorabilidad como hombre de verdad si se desvían de estas normas de conducta los ha llevado a evitar una serie de prácticas temerarias que pudieron poner en riesgo su vida y la de otras personas.

  9. Seed germination of Sierra Nevada postfire chaparral species

    Science.gov (United States)

    Keeley, Jon E.; McGinnis, Thomas W.; Bollens, Kim A.

    2005-01-01

    The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Here we report further germination experiments that elucidate the response of several widespread shrub species whose germination response was not clear and include other species from the Sierra Nevada, which have not previously been included in germination studies. The shrubs Adenostoma fasciculatum and Eriodictyon crassifolium and the postfire annualMentzelia dispersa exhibited highly significant germination in response to smoke treatments, with some enhanced germination in response to heating as well. The shrubs Fremontodendron californicum and Malacothamnus fremontii were stimulated only by heat-shock treatments. Seeds buried in the soil for one year exhibited substantially higher germination for controls and most treatments. In the case of two postfire annuals, Mimulus bolanderi and M. gracilipes, germination of fresh seed was significantly greater with smoke or heating but after soil storage, over two-thirds of the control seeds germinated and treatment effects were not significant. These two annuals are generally restricted to postfire conditions and it is suggested that control germination of soil-stored seed may be a light-response (which was not tested here) as previously reported for another chaparral species in that genus.

  10. Catálogo de la flora del Parque Natural de la Sierra de Mariola (Alicante-Valencia [Checklist of the Natural Park of Sierra de Mariola (Alicante-Valencia, Spain vascular flora

    Directory of Open Access Journals (Sweden)

    Jaume X. SOLER SIGNES

    2012-04-01

    Full Text Available Se presenta la lista actualizada de flora vascular presente en el Parque Natural de la Sierra de Mariola (Alicante-Valencia.SUMMARY. The checklist of the vascular flora of the Natural Park of Sierra de Mariola is here presented.

  11. Sierra/SolidMechanics 4.22 user's guide : addendum for shock capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    2011-10-01

    This is an addendum to the Sierra/SolidMechanics 4.22 User's Guide to document additional capabilities that are available for use in the Presto{_}ITAR code that are not available for use in the standard version of Sierra/SolidMechanics (Sierra/SM). Presto{_}ITAR is an enhanced version of Sierra/SM that provides capabilities that make it regulated under the U.S. Department of State's International Traffic in Arms Regulations (ITAR) export-control rules. This code is part of the Vivace product, and is only distributed to entities that comply with ITAR regulations. The enhancements primarily focus on material models that include an energy-dependent pressure response, appropriate for very large deformations and strain rates. Since this is an addendum to the standard Sierra/SolidMechanics User's Guide, please refer to that document first for general descriptions of code capability and use. This addendum documents material models and element features that support energy-dependent material models.

  12. 78 FR 72926 - Bald and Golden Eagles; Migratory Birds; Phase I Development of the Chokecherry-Sierra Madre Wind...

    Science.gov (United States)

    2013-12-04

    ...), announce our intent to prepare a draft Environmental Impact Statement (EIS) for Phase I of the Chokecherry-Sierra Madre Wind Energy Project. Our draft EIS will analyze the environmental impacts associated with... Chokecherry-Sierra Madre Wind Energy Project AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice...

  13. Airborne Pesticides as an Unlikely Cause for Population Declines of Alpine Frogs in the Sierra Nevada, California

    Science.gov (United States)

    Airborne pesticides from the Central Valley of California have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the mountain yellow-legged frog complex (Rana muscosa and R. sierrae) in the Sierra Nevada. We measured...

  14. 77 FR 23476 - Energia Sierra Juarez U.S., LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2012-04-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Energia Sierra Juarez U.S., LLC; Supplemental Notice That Initial Market... in the above-referenced proceeding of Energia Sierra Juarez U.S., LLC's application for...

  15. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California

    Science.gov (United States)

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour. Copyright ?? 2011 British Lichen Society.

  16. Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierra from California

    Science.gov (United States)

    Purvis, O.W.; Bennett, J.P.; Spratt, J.

    2011-01-01

    An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its colour was due to copper accumulation in the cortex. The present study addressed the hypothesis that the green colour in similar material we sampled from Warren Canyon in 2008, is caused by copper localization in the thallus. Optical microscopy and electron microprobe analysis of specimens of L. sierrae confirmed that copper localization took place in the cortex. Elemental analyses of L. sierrae and three other species from the same localities showed high enrichments of copper and selenium, suggesting that copper selenates or selenites might occur in these lichens and be responsible for the unusual colour.

  17. Structure of Sierra Madera, Texas, as a guide to central peaks of lunar craters.

    Science.gov (United States)

    Howard, K. A.; Wilshire, H. G.; Offield, T. W.

    1972-01-01

    The central peaks of Copernicus or a similar lunar crater have been considered as a target for manned exploration, partly on the supposition that the peaks expose rock uplifted from beneath the crater floor. This supposition is based on an analogy with central uplifts of terrestrial cryptoexplosion structures. Sierra Madera in west Texas is one of these structures. The structure of its central uplift is described as a proposed analog of the central peaks of large lunar impact craters. Setting and stratigraphy of the Sierra Madera are discussed together with structural framework, the central uplift, fold patterns, and fault patterns. It is concluded that the central uplifts of Sierra Madera and similar cryptoexplosion structures appear to be analogous to central peaks of large lunar impact craters.

  18. La actividad neotectónica en la sierra Baja de San Marcos - Cruz del Eje, flanco occidental de las Sierras Pampeanas Orientales Neotectonic activity in the Sierra Baja de San Marcos-Cruz del Eje area, west flank of Sierras Pampeanas Orientales

    Directory of Open Access Journals (Sweden)

    A Massabie

    2003-12-01

    Full Text Available El área pedemontana de San Marcos Sierra-Cruz del Eje constituye, en la provincia de Córdoba, Argentina, una comarca clave para el análisis neotectónico en las Sierras Pampeanas Orientales. En esta región se han realizado estudios centrados en la unidad morfoestructural sierra Baja de San Marcos donde, aplicando un control múltiple de datos estructurales, geomorfológicos, sedimentológicos, paleontológicos y radimétricos, se ha determinado temporal y espacialmente la evolución de la actividad neotectónica del fallamiento andino. Se presentan evidencias sobre la reactivación cuaternaria tardía de la Falla Sierra Baja de San Marcos, conspicua falla inversa de vergencia occidental con componentes de desplazamiento de rumbo y de inclinación, enlazando los episodios tectónicos con las modificaciones del paisaje. Estas modificaciones son expresadas por los depósitos de endicamiento del río Quilpo, por los niveles aterrazados, vinculados a los cauces actuales de los ríos de la Costa (San Marcos y Quilpo, y por los cambios en su desarrollo de la red de avenamiento principal de la región. La edad 14C corregida de 2.560±120 aap, obtenida para los sedimentos del endicamiento permite acotar un primer episodio de actividad, Holoceno tardío, de la Falla Sierra Baja de San Marcos. Las observaciones efectuadas sobre la misma estructura, en una trinchera excavada para su investigación, confirman su extensión hacia el noroeste, dan evidencias sobre una segunda etapa de movimientos en el Holoceno tardío y determinan sus características estructurales comunes a otras fallas con actividad neotectónica estudiadas en las Sierras Pampeanas Orientales, las cuales responden a una mecánica transpresiva.The San Marcos Sierra-Cruz del Eje mountain-piedmont (Córdoba province, Argentina is a key area in order to analyse the neotectonic behaviour of the Sierras Pampeanas Orientales. In this place, the evolution of recent Andean faulting activity has

  19. Dataset of Passerine bird communities in a Mediterranean high mountain (Sierra Nevada, Spain)

    Science.gov (United States)

    Pérez-Luque, Antonio Jesús; Barea-Azcón, José Miguel; Álvarez-Ruiz, Lola; Bonet-García, Francisco Javier; Zamora, Regino

    2016-01-01

    Abstract In this data paper, a dataset of passerine bird communities is described in Sierra Nevada, a Mediterranean high mountain located in southern Spain. The dataset includes occurrence data from bird surveys conducted in four representative ecosystem types of Sierra Nevada from 2008 to 2015. For each visit, bird species numbers as well as distance to the transect line were recorded. A total of 27847 occurrence records were compiled with accompanying measurements on distance to the transect and animal counts. All records are of species in the order Passeriformes. Records of 16 different families and 44 genera were collected. Some of the taxa in the dataset are included in the European Red List. This dataset belongs to the Sierra Nevada Global-Change Observatory (OBSNEV), a long-term research project designed to compile socio-ecological information on the major ecosystem types in order to identify the impacts of global change in this area. PMID:26865820

  20. Dominant Factors Controlling the Hydrometeorology of Northern California: Landfalling Atmospheric Rivers and Sierra Barrier Jets

    Science.gov (United States)

    Neiman, P. J.; Ralph, F. M.; Hughes, M.; Sukovich, E.; Kingsmill, D. E.; Zamora, R. J.; Moore, B. J.

    2014-12-01

    Northern California's Sierra Nevada and Shasta-Trinity mountains are key to the state's water supply and can contribute to major floods in the Central Valley (CV). NOAA's Hydrometeorology Testbed (HMT) program and the CalWater experiment have discovered much about how landfalling atmospheric rivers (AR) and Sierra Barrier Jets (SBJ) modulate orographic precipitation in that region. This presentation provides a review of recent findings, both from case-study and compositing perspectives. Wind-profiler and global-positioning-system (GPS) observations are used with soil moisture probes, stream gauges, and a regional reanalysis dataset. Key results include: Inland-directed ARs override a ~1-km-deep, Sierra-parallel SBJ located above the CV and the western slope of the Sierra. Above the developing SBJ, strengthening southwesterly flow marks the AR. The moistening SBJ reaches maximum intensity during the strongest AR flow aloft, at which time the core of the AR-parallel vapor transport slopes over the SBJ and intersects the Sierra. The SBJ then weakens with the initial cold-frontal passage aloft. A statistical analysis of orographic forcing reveals that both the AR and SBJ are crucial in determining the distribution of precipitation in the northern Sierra and Shasta-Trinity regions due to orographic precipitation enhancement. An open question remains regarding the transport of water vapor near the northern end of the CV. Namely, a portion of the AR-modulated SBJ flow may be transported through a prominent gap in the terrain between Mt. Lassen and Mt. Shasta, near the town of Burney. Recent analyses indicate that this gap allows AR water vapor to penetrate into the western interior (e.g., to Idaho) and thus contribute to heavy precipitation events far inland. The CalWater-2 program of field campaigns has identified diagnosis of the transport through this gap and its impact on northern California precipitation as a priority for future data collection and analysis.

  1. Origen y decadencia del gamonalismo en la sierra ecuatoriana

    Directory of Open Access Journals (Sweden)

    Ibarra Crespo, Hernán

    2002-12-01

    Full Text Available This article analyzes the historical path of gamonalismo in Ecuadorian highlands. Although it could be alike to Mexican caciquismo and Brazilian coronelismo, gamonalismo had its specific forms. In Ecuador it is possible to reconstruct its meaning in political terms, as a form of traditional domination. The use of this particular term is analyzed in different historical moments between the 18th and 20th century; focusing on the origin and decline of this local power. The aim is to build an interpretative frame in order to understand agrarian sources of Ecuadorian state development and ethnic domination.

    Este artículo analiza la trayectoria histórica del gamonalismo en la sierra ecuatoriana. Aunque homologado con el caciquismo mexicano y el coronelismo brasileño, tiene rasgos específicos. En el Ecuador es posible reconstruir el significado del gamonalismo en el lenguaje político y como modalidad de dominación tradicional. Por una parte, se realiza un rastreo y análisis del uso del término en distintos momentos históricos entre los siglos XVIII y XX. Por otra parte, se efectúa un abordaje del origen y declinación de esta forma de poder. Se aspira a construir un marco interpretativo que aporte a la comprensión de los fundamentos agrarios de la constitución del Estado ecuatoriano y las formas de dominación étnica.

  2. Gravity data from the Sierra Vista Subwatershed, Upper San Pedro Basin, Arizona

    Science.gov (United States)

    Kennedy, Jeffrey R.

    2015-01-01

    Observations of very small changes of Earth’s gravitational field (time-lapse gravity) provide a direct, non-invasive method for measuring changes in aquifer storage change. An existing network of gravity stations in the Sierra Vista Subwatershed was revised in 2014 to better understand the spatial distribution of changes in aquifer storage, especially with relation to ephemeral channel recharge and a groundwater cone of depression associated with pumping in the greater Sierra Vista area. In addition, the network was extended to provide baseline data for possible future enhanced-recharge projects.

  3. Numerical Wind Modeling for the San Pedro Mártir Sierra in Baja California

    Directory of Open Access Journals (Sweden)

    K. Vogiatzis

    2004-01-01

    Full Text Available Presentamos la simulación numérica del viento en la Sierra de San Pedro Mártir para realizar una evaluación preliminar de los posibles sitios donde instalar nuevos telescopios. Como criterio inicial, se eligieron los puntos más altos de la sierra, pero a la vez de fácil acceso. Se presentan la altura de la capa límite y el efecto de la turbulencia en los diferentes sitios para velocidades y direcciones del viento típicas.

  4. "Caliban," a poem by Syl Cheney-Coker or Caliban in Sierra Leone 

    OpenAIRE

    Fioupou, Christiane

    2015-01-01

    Une traduction française du poème "Caliban," du romancier et poète sierra-léonais Syl Cheney-Coker, est proposée ici à la suite du texte original ; le poème est précédé d’une courte présentation qui introduit les commentaires du poète sur "son Caliban" et la société krio de Sierra Leone.

  5. Espacio urbano, espacio del consumo en las crónicas norteamericanas de Justo Sierra

    OpenAIRE

    Cristina Beatriz Fernández

    2011-01-01

    El objetivo de este trabajo es analizar las crónicas de viaje de Justo Sierra, escritas en ocasión de su visita a los Estados Unidos a finales del siglo XIX, con énfasis en las dedicadas a la ciudad de Nueva York. En ellas, centramos nuestra atención en el registro textual de fenómenos relacionados con la forma en que Sierra percibe la modernidad norteamericana, especialmente significativa en lo que hace a la relación entre economía y sociedad. Por ello, atendemos particularmente la configura...

  6. Status and understanding of groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units, 2006-2007--California GAMA Priority Basin Project

    Science.gov (United States)

    Fram, Miranda S.; Belitz, Kenneth

    2012-01-01

    Groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The three study units are located in the Sierra Nevada region of California in parts of Nevada, Placer, El Dorado, Madera, Tulare, and Kern Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board, in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The project was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems used for drinking water. The primary aquifer systems (hereinafter, primary aquifers) for each study unit are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for municipal and community drinking-water supply. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to contamination from the surface. The assessments for the Tahoe-Martis, Central Sierra, and Southern Sierra study units were based on water-quality and ancillary data collected by the USGS from 132 wells in the three study units during 2006 and 2007 and water-quality data reported in the CDPH database. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource, and (2) understanding, identification of the natural and human factors affecting groundwater quality. The assessments characterize untreated groundwater quality, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by benchmark concentrations) were used for evaluating groundwater quality for those

  7. Noteworthy records of two species of mammals in the Sierra Madre de Oaxaca, Mexico Registros notables de dos especies de mamíferos de la Sierra Madre de Oaxaca, México

    Directory of Open Access Journals (Sweden)

    Miguel Briones-Salas

    2006-12-01

    Full Text Available We conducted mammal surveys in the Sierra Madre de Oaxaca (Sierra Norte in Oaxaca, Mexico, and recorded the occurrence of two conspicuous mammal species: the spider monkey (Ateles geoffroyi vellerosus and the coyote (Canis latrans cagottis. Spider monkeys has not been previously recorded in the Sierra Madre de Oaxaca, and coyotes have not been previously observed in Mexico at elevations as high as the present one (3 200 mas1 in the Sierra Madre de Oaxaca.Se efectuaron colectas de mamíferos en la Sierra Madre de Oaxaca (Sierra Norte en Oaxaca, México, y se registró la notoria presencia de dos mamíferos: el mono araña (Ateles geoffroyi vellerosus y el coyote (Canis latrans cagottis. El mono araña no se había registrado previamente en la Sierra Madre de Oaxaca, en tanto que el coyote, no había sido registrado en México a tan gran altitud (3 200 m como la de la localidad de captura.

  8. Holocene Paleoearthquake Clustering Along a Sierras Pampeanas (argentina) Bounding Fault?

    Science.gov (United States)

    Costa, C. H.; Ricci, W.; Owen, L. A.; Johnson, W. J.; Halperin, A.; Ahumada, E. A.

    2010-12-01

    The Sierras Pampeanas (Pampean Ranges) of Argentina are characterized by mountain blocks bounded by reverse faults, whose last stage of uplift has been attributed to the shallowing of the Nazca plate (Merlo village (32°21’30,75”S - 64°58’57,77”W ) have exposed two opposing-verging thrusts at the outcrop scale. These structures exhibit a complex interaction and propagate into the Holocene cover. The eastern branch or main fault emplaces Precambrian basement over proximal scarp-derived deposits, whereas the western thrust results in an east-directed fault-propagation fold that deforms wash-slope and fluvio-aeolian deposits. The ages of the fault-related deposits have been reasonably defined through radiocarbon and optically stimulated luminescence methods which provide ages ranging from 7.1+0.4 ka to 350+40 cal yr BP. Evidences of surface deformation are related to multiple-events with colluvial wedges and filling wedges derived from bending-moment ruptures at the fold hinge zone. It has not been possible to unravel whether these structures slipped in simultaneous or separated events which of course impacts in the discrimination of the number of earthquakes recorded in this sequence record. Accordingly, a minimum of four and a maximum of nine surface ruptures younger than 7.1+0.4 ka can be preliminarily interpreted at this trench site, where the elapsed time since the last rupture event is > 350+40 calibrated years BP. Estimated recurrence intervals vary according to different approaches from 0.8 to 3.0 ka (preferred 1.0-2.5 ka), whereas by retrodeforming the total shortening exposed in the trenches, a maximum slip rate of 1.13 mm/year was obtained. Slip rates estimated for the El Molino fault are almost one order of magnitude higher than those estimated at other master bounding faults along neighboring Pampean blocks and appear to be high for an intraplate region with much lower strain rates than the frontal deformation zone of the Andes. The data

  9. Socio-Ecological Factors Affecting Pregnant Women's Anemia Status in Freetown, Sierra Leone

    Science.gov (United States)

    M'Cormack, Fredanna; Drolet, Judy

    2012-01-01

    Background: Sierra Leone has high maternal mortality. Socio-ecological factors are considered contributing factors to this high mortality. Anemia is considered to be a direct cause of 4% of maternal deaths and an indirect cause of 20-40% of maternal deaths. Purpose: The current study explores socio-ecological contributing factors to the anemia…

  10. School Persistence in the Wake of War: Wartime Experiences, Reintegration Supports, and Dropout in Sierra Leone

    Science.gov (United States)

    Zuilkowski, Stephanie Simmons; Betancourt, Theresa S.

    2014-01-01

    This article examines the relationship of wartime experience and reintegration supports to students' risk of school dropout. It draws on longitudinal, mixed-methods data collected among children and youth in Sierra Leone from 2002 through 2008. The study finds that family financial support and perceived social support are positively associated…

  11. Coming back from the bush : gender, youth and reintegration in northern Sierra Leone

    NARCIS (Netherlands)

    Gog, van J.G.

    2008-01-01

    This thesis explores the postwar reintegration strategies of young women who had forcibly become affiliated with one of the fighting factions during the ten years of civil war in Sierra Leone. Instead of conceptualizing reintegration as the result of policies, the author defines it as the dynamic pr

  12. Señales del cambio global en el sitio LTER-Sierra Nevada

    Directory of Open Access Journals (Sweden)

    A.J. Pérez-Luque

    2016-01-01

    Full Text Available La investigación ecológica a largo plazo proporciona información útil para comprender las complejas dinámicas de los sistemas naturales. Esto se hace especialmente importante en las regiones de montaña como Sierra Nevada, que presenta un fuerte gradiente de condiciones ambientales en una escala espacial pequeña. En el sitio LTER-Sierra Nevada se ha implementado un programa de seguimiento a largo plazo que, junto con la integración de información ecológica sobre los ecosistemas nevadenses, está permitiendo evaluar los efectos del cambio global en esta región de montaña. En este trabajo presentamos algunos resultados de los impactos del cambio global sobre los ecosistemas nevadenses, obtenidos tras varios años de implantación del Observatorio del Cambio Global de Sierra Nevada. Además de una evaluación temporal de los principales motores de cambio global (clima y usos del suelo, presentamos varios casos de estudio del impacto del cambio global sobre la componente biótica y socioeconómica de los ecosistemas de Sierra Nevada.

  13. Bodies in action. Culture and body skills in post-conflict Sierra Leone

    NARCIS (Netherlands)

    Niet, van der A.

    2010-01-01

    This book is about human body movement and culture. The body skills of a sample of Sierra Leoneans are analyzed in terms of acquisition of the skills, the importance of learning these skills to become part of a community and the physical consequences of the activities. It focuses on skills in footba

  14. Educating Africans for Inferiority under British Rule: Bo School in Sierra Leone.

    Science.gov (United States)

    Corby, Richard A.

    1990-01-01

    Sierra Leone's Bo School was established in 1906 by British colonial officials to educate chiefs' sons for subordinate positions. Nevertheless, the school contributed to creation of the postindependence ruling class. Enrollment, curriculum, student life, responsibilities of British and African teachers, and alumni networks are examined. Contains…

  15. Mercury in Tadpoles Collected from Remote Alpine Sites in the Southern Sierra Nevada Mountains, California, USA

    Science.gov (United States)

    Amphibians in alpine wetlands of the Sierra Nevada mountains comprise key components of an aquatic-terrestrial food chain, and mercury contamination is a concern because concentrations in fish from this regin exceed thresholds of risk to piscivorous wildlife. Total mercury conc...

  16. Time constraints on the tectonic evolution of the eastern Sierras Pampeanas (Central Argentina)

    DEFF Research Database (Denmark)

    Siegesmund, Siegfried; Steenken, A; Martino, R D;

    2010-01-01

    The application of the SHRIMP U/Pb dating technique to zircon and monazite of different rock types of the Sierras de Córdoba provides an important insight into the metamorphic history of the basement domains. Additional constraints on the Pampean metamorphic episode were gained by Pb/Pb stepwise...

  17. Who cares for former child soldiers? Mental health systems of care in Sierra Leone

    NARCIS (Netherlands)

    Song, S.; van den Brink, H.; de Jong, J.

    2013-01-01

    While numerous studies on former child soldiers (FCS) have shown mental health needs, adequate services are a challenge. This study aimed to identify priorities, barriers and facilitators of mental health care for Sierra Leonean FCS. Thematic analysis was done on 24 qualitative interviews with parti

  18. Palaeomagnetic results from the southern Sierra Madre Oriental, Mexico: evidence for Early Cretaceous or Laramide remagnetization?

    Science.gov (United States)

    Böhnel, H.; Gose, W. A.; Testarmata, M. M.; Bocanegra Noriega, G.

    1990-12-01

    A large suite of samples from the Latest Triassic Huizachal and Early Jurassic Huayacocotla Groups and the Latest Jurassic Taman and Earliest Cretaceous Pimienta Formations was collected in the southern Sierra Madre Oriental for a palaeomagnetic study. Only the samples from three sites belonging to the Huizachal Group and the Las Juntas Formation possibly have retained their primary magnetization. If so, their pole position does not reveal any palaeomagnetically discernable motion relative to cratonic North America. All remaining sites were remagnetized as evidenced by a negative fold test at four sites and the fact that the pole positions cluster better at the 95% significance level if no structural corrections are applied. The tightness of the cluster ( α95 = 4.6 °) and the same polarity, suggest that the samples were remagnetized at some common time. These results permit two interpretations. (1) If the sampling region has not suffered any significant tectonic rotation, then the remagnetization can be dated by comparison with the polar wander path for North America as Early Cretaceous (≈ 130 Ma). This Early Cretaceous phase of deformation is not recognized in the northern Sierra Madre Oriental and clearly pre-dates the Early Tertiary Laramide orogeny. (2) If the southern Sierra Madre Oriental did rotate counterclockwise by ≈ 20 °, then the remagnetization could have originated in any Cretaceous or Early Tertiary time, and may indeed be related to the Laramide deformation. In either case, the data imply that the southern Sierra Madre Oriental constitutes an independent tectonic domain.

  19. GPS Imaging of vertical land motion in California and Nevada: Implications for Sierra Nevada uplift

    Science.gov (United States)

    Hammond, William C.; Blewitt, Geoffrey; Kreemer, Corné

    2016-10-01

    We introduce Global Positioning System (GPS) Imaging, a new technique for robust estimation of the vertical velocity field of the Earth's surface, and apply it to the Sierra Nevada Mountain range in the western United States. Starting with vertical position time series from Global Positioning System (GPS) stations, we first estimate vertical velocities using the MIDAS robust trend estimator, which is insensitive to undocumented steps, outliers, seasonality, and heteroscedasticity. Using the Delaunay triangulation of station locations, we then apply a weighted median spatial filter to remove velocity outliers and enhance signals common to multiple stations. Finally, we interpolate the data using weighted median estimation on a grid. The resulting velocity field is temporally and spatially robust and edges in the field remain sharp. Results from data spanning 5-20 years show that the Sierra Nevada is the most rapid and extensive uplift feature in the western United States, rising up to 2 mm/yr along most of the range. The uplift is juxtaposed against domains of subsidence attributable to groundwater withdrawal in California's Central Valley. The uplift boundary is consistently stationary, although uplift is faster over the 2011-2016 period of drought. Uplift patterns are consistent with groundwater extraction and concomitant elastic bedrock uplift, plus slower background tectonic uplift. A discontinuity in the velocity field across the southeastern edge of the Sierra Nevada reveals a contrast in lithospheric strength, suggesting a relationship between late Cenozoic uplift of the southern Sierra Nevada and evolution of the southern Walker Lane.

  20. Illiteracy, Colonial Legacy and Education: The Case of Modern Sierra Leone.

    Science.gov (United States)

    Banya, Kingsley

    1993-01-01

    As a legacy of British colonial rule, Sierra Leone's education system gives half of its budget to higher education, heavily benefits the upper and middle classes and serves the poor and rural populations badly. The illiteracy rate is 85%. Policy recommendations are outlined for resource allocation and major restructuring of the education system.…

  1. Die Geologie von Camarena de la Sierra und Riodeva (Provinz Teruel, Spanien)

    NARCIS (Netherlands)

    Wz., R. Martin

    1936-01-01

    Als ich im Jahre 1933 ein Gebiet für meine Feldarbeit suchte, wählte ich auf Veranlassung von Herrn Dr. I. M. van der Vlerk die Gemeinde Camarena de la Sierra südlich von Teruel, wo G. R. J. Terpstra, damals Student der Geologie zu Leiden, im Sommer 1931 eine geologische Aufnahme angefangen hatte, w

  2. Sierra Leone's Former Child Soldiers: A Longitudinal Study of Risk, Protective Factors, and Mental Health

    Science.gov (United States)

    Betancourt, Theresa S.; Brennan, Robert T.; Rubin-Smith, Julia; Fitzmaurice, Garrett M.; Gilman, Stephen E.

    2010-01-01

    Objective: To investigate the longitudinal course of internalizing and externalizing problems and adaptive/prosocial behaviors among Sierra Leonean former child soldiers and whether postconflict factors contribute to adverse or resilient mental health outcomes. Method: Male and female former child soldiers (N = 260, aged 10 to 17 years at…

  3. Eocene activity on the Western Sierra Fault System and its role incising Kings Canyon, California

    Science.gov (United States)

    Sousa, Francis J.; Farley, Kenneth A.; Saleeby, Jason; Clark, Marin

    2016-04-01

    Combining new and published apatite (U-Th)/He and apatite 4He/3He data from along the Kings River canyon, California we rediscover a west-down normal fault on the western slope of the southern Sierra Nevada, one of a series of scarps initially described by Hake (1928) which we call the Western Sierra Fault System. Integrating field observations with apatite (U-Th)/He data, we infer a single fault trace 30 km long, and constrain the vertical offset across this fault to be roughly a kilometer. Thermal modeling of apatite 4He/3He data documents a pulse of footwall cooling near the fault and upstream in the footwall at circa 45-40 Ma, which we infer to be the timing of a kilometer-scale incision pulse resulting from the fault activity. In the context of published data from the subsurface of the Sacramento and San Joaquin Valleys, our data from the Western Sierra Fault System suggests an Eocene tectonic regime dominated by low-to-moderate magnitude extension, surface uplift, and internal structural deformation of the southern Sierra Nevada and proximal Great Valley forearc.

  4. Potential increase in floods in California's Sierra Nevada under future climate projections

    Science.gov (United States)

    Das, T.; Dettinger, M.D.; Cayan, D.R.; Hidalgo, H.G.

    2011-01-01

    California's mountainous topography, exposure to occasional heavily moisture-laden storm systems, and varied communities and infrastructures in low lying areas make it highly vulnerable to floods. An important question facing the state-in terms of protecting the public and formulating water management responses to climate change-is "how might future climate changes affect flood characteristics in California?" To help address this, we simulate floods on the western slopes of the Sierra Nevada Mountains, the state's primary catchment, based on downscaled daily precipitation and temperature projections from three General Circulation Models (GCMs). These climate projections are fed into the Variable Infiltration Capacity (VIC) hydrologic model, and the VIC-simulated streamflows and hydrologic conditions, from historical and from projected climate change runs, allow us to evaluate possible changes in annual maximum 3-day flood magnitudes and frequencies of floods. By the end of the 21st Century, all projections yield larger-than-historical floods, for both the Northern Sierra Nevada (NSN) and for the Southern Sierra Nevada (SSN). The increases in flood magnitude are statistically significant (at p rain and less as snow. Increases in antecedent winter soil moisture also play a role in some areas. Thus, a complex, as-yet unpredictable interplay of several different climatic influences threatens to cause increased flood hazards in California's complex western Sierra landscapes. ?? 2011 Springer Science+Business Media B.V.

  5. Telegrama de Justo Sierra a Miguel de Unamuno. [S.l.], 1910?

    OpenAIRE

    Sierra, Justo, 1848-1912

    2009-01-01

    Telegrama del escritor, abogado y profesor mexicano Justo Sierra, secretario de Información Pública y Bellas Artes, a Miguel de Unamuno informándole que las universidades de Salamanca, París y California apadrinarán la inauguración de la Universidad Nacional Autónoma de México.

  6. Genotypic anomaly in ebola virus strains circulating in magazine wharf Area, Freetown, Sierra Leone, 2015

    NARCIS (Netherlands)

    S.L. Smits (Saskia); S.D. Pas (Suzan); C.B.E.M. Reusken (Chantal); B.L. Haagmans (Bart); P. Pertile; C. Cancedda; K. Dierberg; I. Wurie; A. Kamara; D. Kargbo; S.L. Caddy; A. Arias; L. Thorne; J. Lu; U. Jah; I. Goodfellow; M.P.G. Koopmans D.V.M. (Marion)

    2015-01-01

    textabstractThe Magazine Wharf area, Freetown, Sierra Leone was a focus of ongoing Ebola virus transmission from late June 2015. Viral genomes linked to this area contain a series of 13 T to C substitutions in a 150 base pair intergenic region downstream of viral protein 40 open reading frame, simil

  7. Early Phanerozoic trace fossils from the Sierra Albarrana quartzites (Ossa-Morena Zone, Southwest Spain)

    NARCIS (Netherlands)

    Marcos, A.; Azor, A.; González, F.; Simancas, F.

    1991-01-01

    Three ichnogenera are described from a 50 to 500 m thick shallow-water sandstone-shale sequence (Sierra Albarrana Quartzites). The ichnofauna consists of the burrows of worm-like animals (Arenicolites, Monocraterion, and Skolithos). The age of this formation, previously considered to be Precambrian

  8. Empowering Women through Education: Evidence from Sierra Leone. NBER Working Paper No. 18016

    Science.gov (United States)

    Mocan, Naci H.; Cannonier, Colin

    2012-01-01

    We use data from Sierra Leone where a substantial education program provided increased access to education for primary-school age children but did not benefit children who were older. We exploit the variation in access to the program generated by date of birth and the variation in resources between various districts of the country. We find that…

  9. Sierra Leone's Former Child Soldiers: A Follow-Up Study of Psychosocial Adjustment and Community Reintegration

    Science.gov (United States)

    Betancourt, Theresa Stichick; Borisova, Ivelina Ivanova; Williams, Timothy Philip; Brennan, Robert T.; Whitfield, Theodore H.; de la Soudiere, Marie; Williamson, John; Gilman, Stephen E.

    2010-01-01

    This is the first prospective study to investigate psychosocial adjustment in male and female former child soldiers (ages 10-18; n = 156, 12% female). The study began in Sierra Leone in 2002 and was designed to examine both risk and protective factors in psychosocial adjustment. Over the 2-year period of follow-up, youth who had wounded or killed…

  10. "Farming Miners" or "Mining Farmers"?: Diamond Mining and Rural Development in Post-Conflict Sierra Leone

    Science.gov (United States)

    Maconachie, Roy; Binns, Tony

    2007-01-01

    Sierra Leone is currently emerging from a brutal civil war that lasted most of the 1990s, and now has the dubious distinction of being ranked among the world's poorest countries. As thousands of displaced people move back to their villages, a large proportion of the predominantly farm-based rural population are growing food crops for the first…

  11. Training for Innovation: Capacity-Building in Agricultural Research in Post-War Sierra Leone

    Science.gov (United States)

    Gboku, Matthew L. S.; Bebeley, Jenneh F.

    2016-01-01

    This paper examines how the Sierra Leone Agricultural Research Institute (SLARI) used training and development to build capacity for innovation in agricultural research following the country's civil war which ended in 2002. The Institute's training for innovation addressed different agricultural product value chains (APVCs) within the framework of…

  12. Reconstruction versus Transformation: Post-War Education and the Struggle for Gender Equity in Sierra Leone

    Science.gov (United States)

    Maclure, Richard; Denov, Myriam

    2009-01-01

    In post-war contexts, education is widely regarded as essential not only for civic reconciliation, but also as a key force for gender equity. In Sierra Leone, however, despite enhanced educational opportunities for girls, much of the emphasis on post-war educational reconstruction is unlikely to rectify gender inequities that remain entrenched…

  13. Pesticide Distributions and Population Declines of California Alpine Frogs, Rana Muscosa and Rana Sierrae

    Science.gov (United States)

    Atmospherically deposited pesticides from the intensively cultivated Central Valley of California have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the frogs Rana muscosa and Rana sierrae at high elevation in th...

  14. PARTITIONING OF WATER FLUX IN A SIERRA NEVADA PONDEROSA PINE PLANTATION. (R826601)

    Science.gov (United States)

    The weather patterns of the west side of the Sierra Nevada Mountains (cold, wet winters and hot, dry summers) strongly influence how water is partitioned between transpiration and evaporation and result in a specific strategy of water use by ponderosa pine trees (Pinus pond...

  15. Quantifying the Effects of Wildfire Severity on Snow Water Equivalent in the Sierra Nevada

    Science.gov (United States)

    Nguyen, A.; Cunningham, S.; Sodergren, C.; Anzelc, J.; Cate, N.; Arya, V.

    2015-12-01

    Snowpack in the Sierra Nevada is a crucial component of the California water supply. Climate change effects on forest ecosystems in this region have reduced snowpack and resulted in earlier snowmelt. Wildfire frequency and severity in the Sierra Nevada have also increased, due to higher temperatures, drought, and a legacy of fire suppression policies leading to fuel loads augmented beyond the historic range of variability. These combined factors have the potential to severely impact California water supply. Using 2014 California Basin Characterization Model (BCM) climate data and automated classification of various Landsat imagery, this study geospatially quantified the effects of low, moderate, and high- severity wildfire on snowpack and snow water equivalent (SWE) in the Sierra Nevada. An assessment of modeled SWE data were also conducted to examine its usefulness in better understanding areas effected by wildfire. Results indicate little to no significant change in post-fire SWE for high and moderate severity wildfire, however, delineated a significant decrease in post-fire SWE in the low severity wildfire. Additionally, tests show little no significant change in fractional snow cover post-fire. This use of remote sensing and modeled data will assist in decision and policy making related to management of forest ecosystems and water resources within the Sierra Nevada.

  16. Hacia una Estrategia de Desarrollo para la Sierra Rural en el Perú

    NARCIS (Netherlands)

    Escobal, J.A.; Valdivia, L.

    2004-01-01

    El objetivo de este proyecto es elaborar un documento que establezca los lineamientos de una política de desarrollo para la Sierra rural en el Perú e identificar los requerimientos institucionales y de investigación complementaria que se requerirían para la construcción de programas específicos que

  17. The Mono Arch, eastern Sierra region, California: Dynamic topography associated with upper-mantle upwelling?

    Science.gov (United States)

    Jayko, A.S.

    2009-01-01

    A broad, topographic flexure localized east of and over the central and southern Sierra Nevada, herein named the Mono Arch, apparently represents crustal response to lithospheric and/or upper-mantle processes, probably dominated by mantle upwelling within the continental interior associated Pacific-North American plate-boundary deformation. This zone of flexure is identified through comparison between the topographic characteristics of the active Cascade volcanic arc and backarc regions with the analogous former arc and backarc in the Sierra Nevada and eastern Sierra Nevada. Serial topographic profiles measured normal to the modern Cascade backarc reveal an accordance of topographic lows defined by valley floors with an average minimum elevation of ???1400-1500m for over 175km to the southeast. Although the accordance drops in elevation slightly to the south, the modern Cascade backarc region is remarkably level, and is characterized by relief up to ???750m above this baseline elevation. By contrast, serial topographic profiles over the former arc and backarc transitions of the eastern Sierra region exhibit a regional anticlinal warping defined by accordant valley floors and by a late Miocene-early Pliocene erosion surface and associated deposits. The amplitude of this flexure above regionally flat baseline elevations to the east varies spatially along the length of the former Sierran arc, with a maximum of ???1000m centred over the Bridgeport Basin. The total zone of flexure is approximately 350km long N-S and 100km wide E-W, and extends from Indian Wells Valley in the south to the Sonora Pass region in the north. Previous geophysical, petrologic, and geodetic studies suggest that the Mono Arch overlies a zone of active mantle upwelling. This region also represents a zone crustal weakness formerly exploited by the middle-to-late Miocene arc and is presently the locus of seismic and volcanic activities. This seismic zone, which lies east of the Sierra Nevada block

  18. Population dynamics of spotted owls in the Sierra Nevada, California

    Science.gov (United States)

    Blakesley, J.A.; Seamans, M.E.; Conner, M.M.; Franklin, A.B.; White, Gary C.; Gutierrez, R.J.; Hines, J.E.; Nichols, J.D.; Munton, T.E.; Shaw, D.W.H.; Keane, J.J.; Steger, G.N.; McDonald, T.L.

    2010-01-01

    The California spotted owl (Strix occidentalis occidentalis) is the only spotted owl subspecies not listed as threatened or endangered under the United States Endangered Species Act despite petitions to list it as threatened. We conducted a meta-analysis of population data for 4 populations in the southern Cascades and Sierra Nevada, California, USA, from 1990 to 2005 to assist a listing evaluation by the United States Fish and Wildlife Service. Our study areas (from N to S) were on the Lassen National Forest (LAS), Eldorado National Forest (ELD), Sierra National Forest (SIE), and Sequoia and Kings Canyon National Parks (SKC). These study areas represented a broad spectrum of habitat and management conditions in these mountain ranges. We estimated apparent survival probability, reproductive output, and rate of population change for spotted owls on individual study areas and for all study areas combined (meta-analysis) using model selection or model-averaging based on maximum-likelihood estimation. We followed a formal protocol to conduct this analysis that was similar to other spotted owl meta-analyses. Consistency of field and analytical methods among our studies reduced confounding methodological effects when evaluating results. We used 991 marked spotted owls in the analysis of apparent survival. Apparent survival probability was higher for adult than for subadult owls. There was little difference in apparent survival between male and female owls. Model-averaged mean estimates of apparent survival probability of adult owls varied from 0.811 ?? 0.021 for females at LAS to 0.890 ?? 0.016 for males at SKC. Apparent survival increased over time for owls of all age classes at LAS and SIE, for adults at ELD, and for second-year subadults and adults at SKC. The meta-analysis of apparent survival, which included only adult owls, confirmed an increasing trend in survival over time. Survival rates were higher for owls on SKC than on the other study areas. We analyzed data

  19. A new species of Bolitoglossa (Amphibia, Caudata) from the Sierra de Juárez, Oaxaca, Mexico.

    Science.gov (United States)

    Rovito, Sean M; Parra-Olea, Gabriela; Lee, Dana; Wake, David B

    2012-01-01

    We describe a new species of Bolitoglossa (Nanotriton) from the Sierra de Juárez and Sierra Mixe of Oaxaca, Mexico. Bolitoglossa chinantecasp. n. is distinguished from the three other species in the subgenus Nanotriton by its more robust body, by having substantial numbers of maxillary teeth and differences in relative head width, foot width, and limb length. The new species occurs in sympatry with Bolitoglossa (Nanotriton) rufescens at the type locality. The description of another species of salamander from the Sierra de Juárez is noteworthy, given the already high plethodontid salamander species richness of the region.

  20. Deep Crustal Earthquakes and Repeating Earthquakes in the West-Central Sierra Nevada, Western USA

    Science.gov (United States)

    Hurd, O.; Frassetto, A.; Zandt, G.; Gilbert, H.; Jones, C.; Owens, T. J.

    2006-12-01

    The Sierra Nevada EarthScope Project (SNEP) is a multiple institution, collaborative research project focused on investigating the structure and evolution of the Sierra Nevada batholith in eastern California. The first phase of the project (summer 2005-summer 2006) saw the deployment of over forty (40) broadband seismometers spanning the central Sierra Nevada from Fresno, California to just south of the Lake Tahoe region. These seismic stations recorded many small, local earthquakes in both the western foothills and high Sierra Nevada that were mostly located from 20 to 120 km north of Fresno and were not present in other regional catalogs. Seismicity in this region is notable because it occurs in the interior of a plate away from major known faults. Ninety (90) events were picked on as many as 20 SNEP stations and located. These events occurred from late May 2005 to late January 2006 at a rate of ~10 per month and were located between 10 and 35 km depth. Many of the events fall within two distinct clusters beneath the array. The first cluster contains ~45 events and is located 30-70 km east of Merced, California and 30-90 km north of Fresno, California. The second represents ~30 events and is centered about the southern Yosemite National Park region. Average depth of the events in the first cluster is ~27 km compared to ~16 km for the events in the second. Past studies have found that events from similar locations in the western Sierra Nevada foothills exhibited ML magnitudes from 0 to 3.2 and had focal mechanisms displaying strike-slip faulting combined with normal and reverse components (Wong and Savage, 1983, BSSA). Direct comparison between waveforms of picked events occurring in small clusters (2-5 events) found that some events had nearly identical waveforms. This suggests similar rupture locations and characteristics despite the events having occurred a couple days to several weeks apart.

  1. Dense Root Removal by Asymmetric Delamination in Sierra Nevada, California: Insights from Numerical Modeling

    Science.gov (United States)

    Valera, J.; Negredo, A. M.; Billen, M.

    2008-12-01

    Recent studies provide compelling evidence for an event of removal of lithospheric mantle in southern -and possibly central- Sierra Nevada (SN) mountains, California (Zandt et al., Nature, 431, 2004). A sequential history of foundering of the ultramafic root of the Sierra Nevada batholith, with a pronounced asymmetric flow, is proposed to explain a number of geophysical and geological observations, including a fast seismic velocity in the mantle located to the west of the SN crest, a gap in the Moho, recent subsidence and tilting of the Sierra Nevada, and a change in mineralogy of the xenolith population recorded at the surface. In the present study we focus on the quantitative evaluation of this conceptual model. We apply new thermo- mechanical algorithms, developed in MATLAB code, suitable to study the temporal evolution of laterally migrating lithospheric delamination. The motion equation, formulated in terms of the stream function, and the coupled thermal equation are solved applying finite difference techniques. Our physical modeling is shown to properly reproduce the first order features of the conceptual model for lithospheric delamination in the Sierra Nevada. We investigate the evolution of a dense ultramafic root, which brings about a Rayleigh-Taylor gravitational instability. Following our preliminary results, the presence of a fluid-weakened lithosphere, located just east of Sierra Nevada, is required to reproduce the asymmetric development of this instability, as previously proposed by Zandt et al. (2004). This weak rheology zone, which is modeled by means of a reduced viscosity, is shown to enable the ascent of asthenospheric material and westward propagation of delamination. Our predictions are also consistent with the previous inference of the V-shaped cone of crust being dragged down into the downwelling mantle (i.e., the Moho gap). Present results highlight that viscous drag is also likely responsible for present-day surface subsidence.

  2. A new epigean species of the genus Anelpistina (Insecta: Zygentoma: Nicoletiidae from Sierra de El Abra, Taninul, Mexico

    Directory of Open Access Journals (Sweden)

    Luis Espinasa

    2015-11-01

    Full Text Available Anelpistina taninuli sp. nov. (Insecta: Zygentoma: Nicoletiidae, a species from Taninul, Sierra de El Abra, San Luis Potosi, Mexico, is described. We also report the 16S rRNA sequence of this new species.

  3. Composition of modern sand from the Sierra Nevada, California, USA: Implications for actualistic petrofacies of continental-margin magmatic arcs

    OpenAIRE

    Ingersoll, Raymond V.; Eastmond, Daniel J.

    2007-01-01

    The Sierra Nevada of California represents the roots of a long-lived magmatic arc (primarily Cretaceous) that is presently being dissected as the range is uplifted, beginning in the south and progressing northward. This dissection is occurring concurrently with northward migration of the Mendocino triple junction, south of which magmatic-arc activity is absent, and north of which magmatic-arc activity continues. A north-to-south transect along the Sierra Nevada represents transitions of activ...

  4. Analysis of Security Sector Reform in Post-Conflict Sierra Leone: A Comparison of Current versus Historical Capabilities

    Science.gov (United States)

    2010-03-01

    Congo; Andrew Dorman. ’The British Experience of Low-Intensity Conflict in Sierra Leone, Defense & Security Analysis 23:2, 191; “Sierra Leone...considerably effective” in combating piracy, smuggling and illegal fishing in its territorial waters, with the craft donated by China having had a considerable...and assisted in the rescue and recovery of several dozen survivors and at least 150 corpses from the stricken vessel.114 Although some families of

  5. Geochronologic, Isotopic, and Trace Element Constraints on Zircon Recycling in Sierra Crest Intrusive Suites, Sierra Nevada Batholith, USA

    Science.gov (United States)

    Miller, J. S.; Lackey, J.; Memeti, V.; Hirt, W. H.; Wooden, J. L.

    2011-12-01

    Owing to its ubiquity and chemical properties, zircon is the primary tool for obtaining age information from felsic igneous rocks. Numerous geochronologic studies in ancient and recent plutonic and volcanic rocks over the last decade have shown: (1) that assemblages of zircons from single hand samples rarely crystallized at the same time; (2) that zircons from single hand samples may have variable geochemistry and isotopic compositions requiring distinct growth environments. Nonetheless, the conditions under which diverse assemblages of magmatic zircons crystallize, are dispersed and then gathered within such magma systems are less well understood. We have initiated a systematic geochemical (trace element) and isotopic (δ18O, 176Hf/177Hf) investigation of zircons from dated plutons within several of the Cretaceous Sierran Crest zoned intrusive suites of the Sierra Nevada Batholith to better understand melt sources and zircon recycling within these large magma systems. Preliminary O and Hf isotopic results indicate that zircon assemblages between different intrusive suites have variable isotopic compositions with multiple crustal and mantle sources involved. Preliminary trace element analysis of some of the zircon suites also show appreciable variability but important trends have emerged from the data. In particular, there are pronounced differences between trace element patterns and ratios of the youngest, interior, K-feldspar megacryst-bearing granodiorites (e.g. Cathedral Peak, Mono Creek, Whitney) and the older outer units of the intrusive suites, which are generally more mafic granodiorites and tonalites. In contrast to the more mafic outer units, zircons from the inner megacryst-bearing intrusions are overwhelmingly characterized by low Ti-in-zircon (Tzrn,Ti) model temperatures (regardless of uncertainties in aTiO2), low concentrations of MREEs, high Yb/Gd, low Th/U, high Hf, and high Eu/Eu*. These characteristics, and generally low Zr contents of the

  6. Evaluating potential overlap between pack stock and Sierra Nevada bighorn sheep (Ovis canadensis sierrae) in Sequoia and Kings Canyon National Parks, California

    Science.gov (United States)

    Klinger, Robert C.; Few, Alexandra P.; Knox, Kathleen A.; Hatfield, Brian E.; Clark, Jonathan; German, David W.; Stephenson, Thomas R.

    2015-01-01

    Pack stock (horses, mules, burros, llamas, and goats) are frequently assumed to have negative effects on public lands, but there is a general lack of data to be able to quantify the degree to which this is actually the case. Sequoia and Kings Canyon National Parks have received complaints that pack stock may affect Sierra Nevada bighorn sheep (Ovis canadensis sierrae; SNBS), a federally endangered subspecies that occurs in largely disjunct herds in the Sierra Nevada Range of California. The potential effects are thought to be displacement of SNBS from meadows on their summer range (altered habitat use) or, more indirectly, through changes in SNBS habitat or forage quality. Our goals were to conduct an association analysis to quantify the degree of potential spatial overlap in meadow use between SNBS and pack stock and to compare differences in vegetation community composition, structure, and diversity among meadows with different levels of use by bighorn sheep and pack stock. For the association analysis, we used two approaches: (1) we quantified the proportion of meadows that were within the herd home ranges of bighorn sheep and were potentially open to pack stock, and, (2) we used Monte Carlo simulations and use-availability analyses to compare the proportion of meadows used by bighorn sheep relative to the proportional occurrence or area of meadows available to bighorn sheep that were used by pack stock. To evaluate potential effects of pack stock on meadow plant communities and SNBS forage, we sampled vegetation in 2011 and 2012 at 100 plots to generate data that allowed us to compare:

  7. A new species of Cryptotis (Mammalia, Eulipotyphla, Soricidae) from the Sierra de Perijá, Venezuelan-Colombian Andes

    Science.gov (United States)

    Quiroga-Carmona, Marcial; Woodman, Neal

    2015-01-01

    The Sierra de Perijá is the northern extension of the Cordillera Oriental of the Andes and includes part of the border between Colombia and Venezuela. The population of small-eared shrews (Mammalia, Eulipotyphla, Soricidae, Cryptotis) inhabiting the Sierra de Perijá previously was known from only a single skull from an individual collected in Colombia in 1989. This specimen had been referred to alternatively as C. thomasi and C. meridensis, but more precise definition of the known Colombian and Venezuelan species of Cryptotis has since excluded the Sierra de Perijá population from any named species. The recent collection of a specimen from the Venezuelan slope of Sierra de Perijá, prompted us to re-evaluate the taxonomic status of this population and determine its relationship with other Andean shrews. Our examination of the available specimens revealed that they possess a unique suite of morphological and morphometrical characters, and we describe the Sierra de Perijá population as a new species in the South American C. thomasi species group. Recognition of this new species adds to our knowledge of this genus in South America and to the biodiversity of the Sierra de Perijá.

  8. Provenance of the late Proterozoic to early Cambrian metaclastic sediments of the Sierra de San Luis (Eastern Sierras Pampeanas) and Cordillera Oriental, Argentina

    Science.gov (United States)

    Drobe, Malte; López de Luchi, Mónica G.; Steenken, André; Frei, Robert; Naumann, Rudolf; Siegesmund, Siegfried; Wemmer, Klaus

    2009-10-01

    Provenance studies have been performed utilising major and trace elements, Nd systematics, whole rock Pb-Pb isotopes and zircon U/Pb SHRIMP data on metasedimentary rocks of the Sierra de San Luis (Nogolí Metamorphic Complex, Pringles Metamorphic Complex, Conlara Metamorphic Complex and San Luis Formation) and the Puncoviscana Formation of the Cordillera Oriental. The goal was the characterisation of the different domains in the study area and to give insights to the location of the source rocks. An active continental margin setting with typical composition of the upper continental crust is depicted for all the complexes using major and trace elements. The Pringles Metamorphic Complex shows indications for crustal recycling, pointing to a bimodal provenance. Major volcanic input has to be rejected due to Th/Sc, Y/Ni and Cr/V ratios for all units. The ɛNd (540 Ma) data is lower for the San Luis Formation and higher for the Conlara Metamorphic Complex, as compared to the other units, in which a good consistency is given. This is similar to the TDM ages, where the metapsammitic samples of the San Luis Formation are slightly older. The spread of data is largest for the Pringles Metamorphic Complex, again implying two different sources. The whole rock 207Pb/ 206Pb isotopic data lies in between the South American and African sources, excluding Laurentian provenances. The whole rock Pb-Pb data is almost indistinguishable in the different investigated domains. Only the PMC shows slightly elevated 208Pb/ 204Pb values. Possible source rocks for the different domains could be the Quebrada Choja in the Central Arequipa-Antofalla domain, the Southern domain of the Arequipa-Antofalla basement, the Brazilian shield or southern Africa. Zircon SHRIMP data point to a connection between the Puncoviscana Formation and the Conlara Metamorphic Complex. Two maxima around 600 Ma and around 1000 Ma have been determined. The Nogolí Metamorphic Complex and the Pringles Metamorphic Complex

  9. DATACIONES ARQUEOMAGNÉTICAS EN LA CIUDADELA DE TEOTIHUACAN, SIERRA DE LAS NAVAJAS Y XALASCO (Archaeomagnetic Datings in the Citadel of Teotihuacan, Sierra de las Navajas, and Xalasco

    Directory of Open Access Journals (Sweden)

    Anuar Gabriel Terán Guerrero

    2016-03-01

    Full Text Available El control cronoestratigráfico es fundamental para el desarrollo del trabajo arqueológico, por ello el arqueomagnetismo se ha constituido como una gran herramienta para las dataciones. En este trabajo se muestran los resultados de dataciones arqueomagnéticas mediante la determinación de la dirección de magnetización de pisos de estuco de tres sitios de la cultura teotihuacana: Ciudadela de Teotihuacan, Sierra de las Navajas y Xalasco, Tlaxcala. Esta cultura se desarrolló en el centro de México a partir del año 1 d. C., teniendo su mayor esplendor durante los siglos IV al VI d. C. Tres etapas constructivas fueron muestreadas en la ciudadela de Teotihuacan: la preciudadela, la pirámide de Quetzalcóatl y la pirámide adosada. La Sierra de las Navajas en Hidalgo, a 50 km de Teotihuacan, era su principal proveedor de obsidiana, por lo que es de interés conocer sus periodos de ocupación. El motivo del análisis de los pisos de Xalasco, Tlaxcala, sitio de la cultura teotihuacana, es por encontrarse en la ruta de comunicación con la zona del Golfo de México. Utilizando la metodología y el programa de Pavón-Carrasco et al. (2014 se infieren intervalos de tiempo que nos permiten comprender la dinámica ocupacional de estos sitios. ENGLISH: The chronostratigraphic control is fundamental during any archaeological survey. Recent studies over the Americas showed that archaeomagnetism emerges as a great tool for absolute dating purposes. In this paper, we report new archaeomagnetic datings obtained from stucco floors belonging to three sites of Teotihuacan: the Citadel of Teotihuacan, Sierra de las Navajas and Xalasco, Tlaxcala. This culture developed in central Mexico from AD 1, having its greatest splendor during the 4th to 6th centuries AD. Three construction phases were sampled in the citadel of Teotihuacan: the pre-Citadel, the Pyramid of Quetzalcoatl and the terraced pyramid. The Sierra de la Navajas in Hidalgo, located 50 km from

  10. Diversidad de mamíferos de la Reserva Natural Sierra Nanchititla, México Diversity of mammals in the Natural Reserve Sierra Nanchititla, Mexico

    Directory of Open Access Journals (Sweden)

    Octavio Monroy-Vilchis

    2011-03-01

    Full Text Available La Reserva Natural Sierra Nanchititla (RNSN, por su extensión, es la segunda área natural protegida del Estado de México; sin embargo, se desconoce gran parte de su biodiversidad. El objetivo de este trabajo fue estimar su diversidad mastofaunística. Se utilizó el trampeo directo para la colecta de mamíferos pequeños y trampas-cámara para el estudio de los mamíferos medianos y grandes. Se calculó la diversidad a partir del índice de Margalef, y se evaluaron la dominancia y la equidad mediante los índices de Simpson y Shannon-Wiener, respectivamente. Se registraron 53 especies de mamíferos; 3 de ellas son el primer registro estatal, 10 son endémicas de México y 4 las considera en alguna categoría de vulnerabilidad el gobierno mexicano. En la zona habitan 5 de las 6 especies de felinos de México. La composición mastofaunística de la RNSN fue comparada con la de la sierra Purépecha, Michoacán, con la que comparte el 38% de las especies. De acuerdo con el índice de Jaccard, la similitud entre ambas es baja. Considerando los resultados, la importancia de la RNSN con respecto a su diversidad mastofaunística es evidente, así como la necesidad de delinear estrategias para su conservación.The Sierra Nanchititla Natural Reserve (SNNR is the second largest natural protected area in the State of Mexico, however its biodiversity is largely unknown. The aim of this research was to estimate its mammalian diversity. Direct trapping was used to capture small mammals and camera-trapping for the study of medium and large mammals. Diversity was calculated from Margalef's index, dominance and equity were evaluated through Simpson's and Shannon-Wiener indexes, respectively. Fifty three species were registered, 3 of them are the first record for the State of Mexico, 10 are endemic to Mexico and 4 are considered in some category of vulnerability by the Mexican government. The area is inhabited by 5 of the 6 Mexican felid species. The

  11. Anfibios de las Sierras Pampeanas Centrales de Argentina: diversidad y distribución altitudinal

    Directory of Open Access Journals (Sweden)

    Julián N. Lescano

    2015-09-01

    Full Text Available Amphibians from Sierras Pampeanas Centrales of Argentina: diversity and altitudinal distribution. Sierras Pampeanas Centrales (SPC mountains are located in Córdoba and San Luis provinces (Argentina and represent an area of unique biogeographic importance. In this paper we provide a synthesis about the knowledge of diversity and altitudinal distribution of anurans that inhabit SPC mountains. We compiled a species list through different information sources (field data, biological collections and bibliography. Using this information we characterize altitudinal distribution range of each species and analyze associations between species richness and composition and altitude gradient. We recorded 24 amphibians species belonging to five families. These species are heterogeneously distributed over the altitude gradient of SPC. We detect a linear negative relationship between altitude and species richness and defined assemblages associated with different altitude sectors. The results obtained in the paper represent basic information that will be useful to evaluate anthropogenic impact on this particular and fragile mountain system.

  12. Comprehensive yet scalable health information systems for low resource settings: a collaborative effort in sierra leone.

    Science.gov (United States)

    Braa, Jørn; Kanter, Andrew S; Lesh, Neal; Crichton, Ryan; Jolliffe, Bob; Sæbø, Johan; Kossi, Edem; Seebregts, Christopher J

    2010-11-13

    We address the problem of how to integrate health information systems in low-income African countries in which technical infrastructure and human resources vary wildly within countries. We describe a set of tools to meet the needs of different service areas including managing aggregate indicators, patient level record systems, and mobile tools for community outreach. We present the case of Sierra Leone and use this case to motivate and illustrate an architecture that allows us to provide services at each level of the health system (national, regional, facility and community) and provide different configurations of the tools as appropriate for the individual area. Finally, we present a, collaborative implementation of this approach in Sierra Leone.

  13. High altitude wind velocity at Sierra Negra and San Pedro M\\'artir

    CERN Document Server

    Carrasco, E; Carramiñana, A; Carrasco, Esperanza; Avila, Remy; Carrami\\~nana, Alberto

    2004-01-01

    It has been proposed that the global circulation of the atmosphere winds at 200 mb can be used as a criteria to establish the suitability of a site for the development of adaptive optics techniques such as slow wavefront corrugation correction. By using the NOAA NCEP/NCAR Reanalysis data base we analyze the monthly average wind velocity at 200 mb for a 16 year period, for two sites in Mexico: Sierra Negra and San Pedro M\\'artir. We compare the results with those obtained for Mauna Kea, Paranal and La Silla, with Maidanak in Uzbekistan, and with Gamsberg in Namibia. We show that for all the sites under study there is a yearly wind speed modulation and we model that modulation. Our results show that Sierra Negra and San Pedro M\\'artir are comparable with the best observatory sites as Mauna Kea and are amongst the most advantageous sites to apply adaptive optics techniques.

  14. Estimating aboveground biomass for broadleaf woody plants and young conifers in Sierra Nevada, California forests.

    Science.gov (United States)

    McGinnis, Thomas W.; Shook, Christine D.; Keeley, Jon E.

    2010-01-01

    Quantification of biomass is fundamental to a wide range of research and natural resource management goals. An accurate estimation of plant biomass is essential to predict potential fire behavior, calculate carbon sequestration for global climate change research, assess critical wildlife habitat, and so forth. Reliable allometric equations from simple field measurements are necessary for efficient evaluation of plant biomass. However, allometric equations are not available for many common woody plant taxa in the Sierra Nevada. In this report, we present more than 200 regression equations for the Sierra Nevada western slope that relate crown diameter, plant height, crown volume, stem diameter, and both crown diameter and height to the dry weight of foliage, branches, and entire aboveground biomass. Destructive sampling methods resulted in regression equations that accurately predict biomass from one or two simple, nondestructive field measurements. The tables presented here will allow researchers and natural resource managers to easily choose the best equations to fit their biomass assessment needs.

  15. Thymus × pseudogranatensis (Labiatae, nuevo híbrido para Sierra Nevada (España

    Directory of Open Access Journals (Sweden)

    Lorite, Juan

    2011-12-01

    Full Text Available Thymus × pseudogranatensis Vizoso, F.B. Navarro & Lorite, a new spontaneous hybrid of Th. granatensis Boiss. subsp. granatensis and Th. zygis L. subsp. gracilis (Boiss. R. Morales, collected in the dolomitic areas of Sierra Nevada (SE Spain, is described. Morphological characters of the new nothospecies are analysed and its distribution and ecology are discussed.Se describe Thymus × pseudogranatensis Vizoso, F.B. Navarro & Lorite, un nuevo híbrido entre Th. granatensis Boiss. subsp. granatensis y Th. zygis L. subsp. gracilis (Boiss. R. Morales, colectado en la orla dolomítica de Sierra Nevada (SE de España. Se analizan los caracteres morfológicos de la nueva notoespecie y se aportan detalles sobre su hábitat y distribución.

  16. A new species of Rhadinella (Serpentes: Colubridae) from the Sierra Madre del Sur of Guerrero, Mexico.

    Science.gov (United States)

    Campillo, Gustavo; Dávila-Galavíz, Luis Fernando; Flores-Villela, Oscar; Campbell, Jonathan A

    2016-04-12

    We describe a new species of Rhadinella from the Sierra Madre del Sur of Guerrero, Mexico, a region where the genus was previously unknown. This diminutive species is a member of a group of snakes previously allocated in the Rhadinaea godmani group, and more recently transferred to the genus Rhadinella. These snakes may have conspicuous dark longitudinal striping on a pale brown to orange background or may have dark brown to blackish dorsal ground coloration, which mostly or completely obfuscates a pattern of longitudinal striping. The new species is mostly dark with barely discernible slightly paler or darker striping (depending on how striping is interpreted). The closest relative of the new species, on the basis of morphological similarities and biogeography, appears to be Rhadinella donaji which occurs to the east in the Sierra Madre del Sur of Oaxaca about 275 km from the type-locality of the new species.

  17. Propuesta para la construcción del concepto de interculturalldad caso la sierra nevada

    Directory of Open Access Journals (Sweden)

    Julio Marino Barragán

    2014-02-01

    Full Text Available La imponente Sierra Nevada de Santa Marta controla buena parte del clima de toda la  región, gracias a la montaña sagrada los huracanes no son tan devastadores como sí la son por otras latitudes. Así como la Sierra, el  departamento del Magdalena es una de las regiones culturales más ricas del país y de la cuenca del Caribe. En el Magdalena encontramos poblados típicos de la múltiple mezcla, del mestizaje de los sinnúmeros de vertientes culturales que se arriesgan a venir por estas tierras, desde el cercano oriente, la esteparia Rusia.

  18. A Late Proterozoic Early Paleozoic magmatic cycle in Sierra de la Ventana, Argentina

    Science.gov (United States)

    Gregori, D. A.; López, V. L.; Grecco, L. E.

    2005-06-01

    Late Proterozoic-Early Paleozoic intrusive and volcanic rocks of Sierra de la Ventana can be grouped into two magmatic assemblages: the Meyer and Cochenleufú suites. The older (700-570 Ma) is composed of S-type quartz-monzodiorites, synogranites, and monzogranites associated with andesites and rhyolites and related to volcanic-arc and postcollisional settings. The younger (540-470 Ma) corresponds to highly fractionated homogeneous A-type monzogranites, linked to final plutonic events during postorogenic extension in collisional belts. Strong similarities between Sierra de la Ventana magmatic rocks and the S- and A-type granites of the Cape granite suite in South Africa allow positive correlation. In both areas, primitive volcanic arcs or collisional orogens are recognized. Continuous transpressional shearing between the Swartland and Tygerberg terranes in the Saldania belt may have triggered the generation and emplacement of both suites.

  19. Structure of Sierra Blanca (Alpujarride Complex, west of the Betic Cordillera

    Directory of Open Access Journals (Sweden)

    Andreo, B.

    1995-04-01

    Full Text Available Sierra Blanca, situated in the SW of Málaga, forms part of the Blanca unit, belonging to the Alpujarride Complex of the Betic Cordillera. Its lithologic sequences are made up of a group of migmatites, gneisses and schists and an upper formation of marbles (white dolomitic and the bottom and blue calcareous towards the top, linked with a transitional contact. The structure of Sierra Blanca is comprised of folds, generally isoclinal, with reversed limbs and with important tectonic transpositions, the direction of which is approximately E-W in the eastern area and N-S and E-W in the West. In both areas the folds present opposing vergences, consistently towards the interior of the sierra. The origin of these structures is explained with a model of westerly movements of the Blanca unit, in relation to the Los Reales unit, with the formation of frontal and lateral folds. In its advancement, the western part of Sierra Blanca underwent an important anti-clockwise rotation responsible for the co-existence of folds in N-S and E-W directions. These structures occurred under ductile conditions, owing to the presence of important overthrusting peridotitic masses of the Los Reales unit. This model of westerly displacement is inserted in the process undergone by the Betic-Rif Internal Zones (with Blanca and Los Reales units included which occurred at the end of the Oligocene-Early Miocene when the Gibraltar arch began to be formed.Sierra Blanca, situada al SW de Málaga, forma parte de la unidad de Blanca que pertenece al complejo Alpujárride de la Cordillera Bética. Su secuencia litológica está compuesta por un conjunto inferior de migmatitas, gneises y esquistos, y por una formación superior de mármoles, blancos dolomíticos en la base y mármoles calizos azules hacia la parte superior, entre los que existe un tránsito gradual. La estructura de Sierra Blanca está formada por pliegues, generalmente isoclinales, con flancos invertidos que muestran

  20. Nuevas edades radimétricas para la Formación Toro Negro en la Sierra de los Colorados, Sierras Pampeanas Noroccidentales, provincia de La Rioja New radiometric ages for the Toro Negro Fromation in the Sierra de los Colorados, northwestern Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    P.L. Ciccioli

    2005-03-01

    Full Text Available En este trabajo se dan a conocer nuevas edades radimétricas obtenidas por el método K/Ar roca total sobre dos niveles de tobas vítreas de la parte media-superior de la Formación Toro Negro en la sierra de los Colorados, Sierras Pampeanas Noroccidentales (provincia de La Rioja. Las edades 8,6 ± 0,3 Ma y 6,8 ± 0,2 Ma ubican a la Formación Toro Negro en el Mioceno superior modificando así la edad pliocena establecida anteriormente. Los valores obtenidos presentan un alto grado de confiabilidad, dado que se tratan de tobas vítreas las cuales no tienen ningún signo de retransporte, contaminación ni alteración diagenética. Los niveles de tobas han sido mapeados y georeferenciados con coordenadas obtenidas con GPS. Las muestras presentan una precisa ubicación en la columna estratigráfica y se encuentran lo suficientemente próximas de manera de controlar indirectamente los valores obtenidos.New absolute ages derived from whole rock K/Ar dating of two vitric tuffs collected from the upper-middle part of the Toro Negro Formation in the outcrops of the Sierra de Los Colorados, Sierras Pampeanas Noroccidentales (La Rioja Province are presented herein. The obtained values of 8,6 ± 0,3 Ma and 6,8 ± 0,2 Ma respectively, indicate an Upper Miocene age and challenge the previous Pliocene age proposed for this unit. The results presented here have a high degree of confidence because they do not show evidences of reworking, mixing with terrigenous clastics nor diagenetic alteration. The tuff levels were mapped and georeferenced using GPS coordinates and their close location in the stratigraphic column provides an additional control for the obtained ages.

  1. Inversion for Eigenvalues and Modes Using Sierra-SD and ROL.

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Timothy [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Aquino, Wilkins [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ridzal, Denis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kouri, Drew Philip [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    In this report we formulate eigenvalue-based methods for model calibration using a PDE-constrained optimization framework. We derive the abstract optimization operators from first principles and implement these methods using Sierra-SD and the Rapid Optimization Library (ROL). To demon- strate this approach, we use experimental measurements and an inverse solution to compute the joint and elastic foam properties of a low-fidelity unit (LFU) model.

  2. Ten Years of Forest Cover Change in the Sierra Nevada Detected Using Landsat Satellite Image Analysis

    Science.gov (United States)

    Potter, Christopher S.

    2014-01-01

    A detailed geographic record of recent vegetation regrowth and disturbance patterns in forests of the Sierra Nevada remains a gap that can be filled with remote sensing data. Landsat (TM) imagery was analyzed to detect 10 years of recent changes (between 2000 and 2009) in forest vegetation cover for areas burned by wildfires between years of 1995 to 1999 in the region. Results confirmed the prevalence of regrowing forest vegetation during the period 2000 and 2009 over 17% of the combined burned areas.

  3. DIAGNOSIS IMPORTANCE OF RURAL DEVELOPMENT OF A MODEL AGROFORESTAL IN PEASANT COMMUNITIES OF SIERRA DE HUAUTLA

    OpenAIRE

    Miguel Uribe-Gómez; Artemio Cruz-León; Dionicio Juárez-Ramón; Alejandro Lara-Bueno; José L. Romo-Lozano; Ramón Valdivia-Alcalá; Marcos Portillo-Vázquez

    2015-01-01

    Family agricultural is socioeconomically important in rural areas, but in Mexico, from the 80's this production system presents social stagnation. This type of agriculture presents a dynamic reality in the interests of each producer and limiting access to factors of production (land, labor and capital). In this investigation a methodology for analysis and diagnosis of production systems in rural areas, in two communities in the Country Sierra de Huautla Tepalcingo, Morelos, Mexico was applied...

  4. Structural pattern in central uplifts of cryptoexplosion structures as typified by Sierra Madera

    Science.gov (United States)

    Wilshire, H.G.; Howard, K.A.

    1968-01-01

    The pattern of deformation in central uplifts of Sierra Madera and other well-known cryptoexplosion structures indicates that inward as well as upward movement of strata formed the uplifts. This kind of movement is incompatible with structures not of impact origin with which they have been compared. The structural style of cryptoexplosion structures, together with features that suggest shock deformation, supports the belief that they are the eroded roots of impact craters.

  5. Sierra Chata field, Argentina: geophysical discovery and development of a stratigraphic trap

    Energy Technology Data Exchange (ETDEWEB)

    Woller, Kevin L. [Mobil Technology Co. (United States); Louder, William T. [Santa Fe Energy Resources (Argentina)

    1999-07-01

    Drilling a seismic amplitude anomaly in the Cretaceous Mulichinco Sandstone discovered the Sierra Chata gas field in the Neuquen Basin, Argentina. This well followed several unsuccessful attempts to locate hydrocarbons in the block, including a well only 3 kilometers from the closet producing well in the field. Since that time, seismic data has played the major role in locating new wells, all 24 of which have been completed as producers. (author)

  6. Transmission dynamics of Ebola virus disease and intervention effectiveness in Sierra Leone.

    Science.gov (United States)

    Fang, Li-Qun; Yang, Yang; Jiang, Jia-Fu; Yao, Hong-Wu; Kargbo, David; Li, Xin-Lou; Jiang, Bao-Gui; Kargbo, Brima; Tong, Yi-Gang; Wang, Ya-Wei; Liu, Kun; Kamara, Abdul; Dafae, Foday; Kanu, Alex; Jiang, Rui-Ruo; Sun, Ye; Sun, Ruo-Xi; Chen, Wan-Jun; Ma, Mai-Juan; Dean, Natalie E; Thomas, Harold; Longini, Ira M; Halloran, M Elizabeth; Cao, Wu-Chun

    2016-04-19

    Sierra Leone is the most severely affected country by an unprecedented outbreak of Ebola virus disease (EVD) in West Africa. Although successfully contained, the transmission dynamics of EVD and the impact of interventions in the country remain unclear. We established a database of confirmed and suspected EVD cases from May 2014 to September 2015 in Sierra Leone and mapped the spatiotemporal distribution of cases at the chiefdom level. A Poisson transmission model revealed that the transmissibility at the chiefdom level, estimated as the average number of secondary infections caused by a patient per week, was reduced by 43% [95% confidence interval (CI): 30%, 52%] after October 2014, when the strategic plan of the United Nations Mission for Emergency Ebola Response was initiated, and by 65% (95% CI: 57%, 71%) after the end of December 2014, when 100% case isolation and safe burials were essentially achieved, both compared with before October 2014. Population density, proximity to Ebola treatment centers, cropland coverage, and atmospheric temperature were associated with EVD transmission. The household secondary attack rate (SAR) was estimated to be 0.059 (95% CI: 0.050, 0.070) for the overall outbreak. The household SAR was reduced by 82%, from 0.093 to 0.017, after the nationwide campaign to achieve 100% case isolation and safe burials had been conducted. This study provides a complete overview of the transmission dynamics of the 2014-2015 EVD outbreak in Sierra Leone at both chiefdom and household levels. The interventions implemented in Sierra Leone seem effective in containing the epidemic, particularly in interrupting household transmission.

  7. Hydrologic response and watershed sensitivity to climate warming in California's Sierra Nevada.

    Science.gov (United States)

    Null, Sarah E; Viers, Joshua H; Mount, Jeffrey F

    2010-04-01

    This study focuses on the differential hydrologic response of individual watersheds to climate warming within the Sierra Nevada mountain region of California. We describe climate warming models for 15 west-slope Sierra Nevada watersheds in California under unimpaired conditions using WEAP21, a weekly one-dimensional rainfall-runoff model. Incremental climate warming alternatives increase air temperature uniformly by 2 degrees, 4 degrees, and 6 degrees C, but leave other climatic variables unchanged from observed values. Results are analyzed for changes in mean annual flow, peak runoff timing, and duration of low flow conditions to highlight which watersheds are most resilient to climate warming within a region, and how individual watersheds may be affected by changes to runoff quantity and timing. Results are compared with current water resources development and ecosystem services in each watershed to gain insight into how regional climate warming may affect water supply, hydropower generation, and montane ecosystems. Overall, watersheds in the northern Sierra Nevada are most vulnerable to decreased mean annual flow, southern-central watersheds are most susceptible to runoff timing changes, and the central portion of the range is most affected by longer periods with low flow conditions. Modeling results suggest the American and Mokelumne Rivers are most vulnerable to all three metrics, and the Kern River is the most resilient, in part from the high elevations of the watershed. Our research seeks to bridge information gaps between climate change modeling and regional management planning, helping to incorporate climate change into the development of regional adaptation strategies for Sierra Nevada watersheds.

  8. Hydrologic response and watershed sensitivity to climate warming in California's Sierra Nevada.

    Directory of Open Access Journals (Sweden)

    Sarah E Null

    Full Text Available This study focuses on the differential hydrologic response of individual watersheds to climate warming within the Sierra Nevada mountain region of California. We describe climate warming models for 15 west-slope Sierra Nevada watersheds in California under unimpaired conditions using WEAP21, a weekly one-dimensional rainfall-runoff model. Incremental climate warming alternatives increase air temperature uniformly by 2 degrees, 4 degrees, and 6 degrees C, but leave other climatic variables unchanged from observed values. Results are analyzed for changes in mean annual flow, peak runoff timing, and duration of low flow conditions to highlight which watersheds are most resilient to climate warming within a region, and how individual watersheds may be affected by changes to runoff quantity and timing. Results are compared with current water resources development and ecosystem services in each watershed to gain insight into how regional climate warming may affect water supply, hydropower generation, and montane ecosystems. Overall, watersheds in the northern Sierra Nevada are most vulnerable to decreased mean annual flow, southern-central watersheds are most susceptible to runoff timing changes, and the central portion of the range is most affected by longer periods with low flow conditions. Modeling results suggest the American and Mokelumne Rivers are most vulnerable to all three metrics, and the Kern River is the most resilient, in part from the high elevations of the watershed. Our research seeks to bridge information gaps between climate change modeling and regional management planning, helping to incorporate climate change into the development of regional adaptation strategies for Sierra Nevada watersheds.

  9. Resilience Through Disturbance: Effects of Wildfire on Vegetation and Water Balance in the Sierra Nevadas

    Science.gov (United States)

    Boisrame, G. F. S.; Thompson, S. E.; Stephens, S.; Collins, B.; Tague, N.

    2015-12-01

    A century of fire suppression in the Western United States has drastically altered the historically fire-adapated ecology in California's Sierra Nevada Mountains. Fire suppression is understood to have increased the forest cover, as well as the stem density, canopy cover and water demand of montane forests, reducing resilience of the forests to drought, and increasing the risk of catastrophic fire by drying the landscape and increasing fuel loads. The potential to reverse these trends by re-introducing fire into the Sierra Nevada is highly promising, but the likely effects on vegetation structure and water balance are poorly quantified. The Illilouette Creek Basin in Yosemite National Park represents a unique experiment in the Sierra Nevada, in which managers have moved from fire suppression to allowing a near-natural fire regime to prevail since 1972. Changes in vegetation structure in the Illilouette since the restoration of natural burning provides a unique opportunity to examine how frequent, mixed severity fires can reshape the Sierra Nevada landscape. We characterize these changes from 1969 to the present using a combination of Landsat products and high-resolution aerial imagery. We describe how the landscape structure has changed in terms of vegetation composition and its spatial organization, and explore the drivers of different post-fire vegetation type transitions (e.g. forest to shrubland vs. forest to meadow). By upscaling field data using vegetation maps and Landsat wetness indices, we explore how these vegetation transitions have impacted the water balance of the Illilouette Creek Basin, potentially increasing its resilience in the face of drought, climate change, and catastrophic fire. In a region that is adapted to frequent disturbance from fire, this work helps us understand how allowing such natural disturbances to take place can increase the sustainability of diverse landscapes in the long term.

  10. Impact of Summer Cattle Grazing on the Sierra Nevada Watershed: Aquatic Algae and Bacteria

    OpenAIRE

    2012-01-01

    Introduction. We evaluated periphytic algal and microbial communities to assess the influence of human and cattle impact on Sierra water quality. Methods. 64 sites (lakes and streams from Lake Tahoe to Sequoia National Park, California) were sampled for suspended indicator bacteria and algae following standardized procedures. The potential for nonpoint pollution was divided into three categories: cattle-grazing areas (C), recreation use areas (R), or remote wildlife areas (W). Results. Periph...

  11. Cretaceous plutonic rocks in the Donner Lake-Cisco Grove area, northern Sierra Nevada, California

    Science.gov (United States)

    Kulow, Matthew J.; Hanson, Richard E.; Girty, Gary H.; Girty, Melissa S.; Harwood, David S.

    1998-01-01

    The northernmost occurrences of extensive, glaciated exposures of the Sierra Nevada batholith occur in the Donner Lake-Cisco Grove area of the northern Sierra Nevada. The plutonic rocks in this area, which are termed here the Castle Valley plutonic assemblage, crop out over an area of 225 km2 and for the most part are shown as a single undifferentiated mass on previously published geological maps. In the present work, the plutonic assemblage is divided into eight separate intrusive units or lithodemes, two of which each consist of two separate plutons. Compositions are dominantly granodiorite and tonalite, but diorite and granite form small plutons in places. Spectacular examples of comb layering and orbicular texture occur in the diorites. U-Pb zircon ages have been obtained for all but one of the main units and range from ~120 to 114 Ma, indicating that the entire assemblage was emplaced in a narrow time frame in the Early Cretaceous. This is consistent with abundant field evidence that many of the individual phases were intruded penecontemporaneously. The timing of emplacement correlates with onset of major Cretaceous plutonism in the main part of the Sierra Nevada batholith farther south. The emplacement ages also are similar to isotopic ages for gold-quartz mineralization in the Sierran foothills west of the study area, suggesting a direct genetic relationship between the voluminous Early Cretaceous plutonism and hydrothermal gold mineralization.

  12. Latest extension of the Laujar fault in a convergence setting (Sierra Nevada, Betic Cordillera)

    Science.gov (United States)

    Martínez-Martos, Manuel; Galindo-Zaldívar, Jesus; Sanz de Galdeano, Carlos; García-Tortosa, Francisco Juan; Martínez-Moreno, Francisco José; Ruano, Patricia; González-Castillo, Lourdes; Azañón, José Miguel

    2017-02-01

    The present-day relief of the Betic Cordillera formed since the Late Miocene through the regional N-S to NW-SE Africa-Eurasia convergence that developed large folds. The Laujar Fault Zone is a south-dipping E-W oriented structure located at the northern boundary of the Alpujarran Corridor Neogene intramontane basin, which separates Sierra Nevada and Sierra de Gador antiforms, in the Internal Zones of the Betic Cordillera. The fault zone acted in a first stage as a dextral strike-slip fault. Currently it moves as a normal fault evidenced by striated calcretes, also in agreement with regional continuous GPS (CGPS) data that support the hypothesis of an active N-S extension in the fault area. In order to analyse the deep geometry of the Laujar Fault Zone, we combined several geophysical techniques (gravity, magnetic, electric resistivity tomography and audio-magnetotelluric data) with field geological observations. Fault surfaces seem to join at a southward-dipping shallow detachment level, including faults covered by the sedimentary infill. The fault zone was developed in a previously weakened area by wrench faults parallel to the Alpujarran Corridor. The recent normal activity of this fault zone may be a consequence of a change in the Africa-Eurasia convergence orientation, which implies a decrease in the N-S compression component. This structure along the southern limb of Sierra Nevada antiform evidences the gravitational collapse of previously thickened crust in a regional compressional context simultaneous to metamorphic core uplift.

  13. Containing Ebola: A Test for Post-Conflict Security Sector Reform in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Cathy Haenlein

    2015-07-01

    Full Text Available Ebola has provided the greatest test of the Sierra Leonean security sector – and, in turn, of the UK-led reforms of the past ten-to-fifteen years. The performance of the country's security forces at the height of the crisis suggests that there are sound structures in place; however, Ebola has shown that the Government of Sierra Leone's national security architecture still lacks maturity in responding to such a scenario. Drawing on first-hand interviews with advisers on the ground, this article explores the Sierra Leone government’s response to the Ebola crisis and the performance of the security sector so far, within the wider context of UK-led security-sector reform (SSR since the end of the civil war. In doing so, it highlights a number of lessons to have emerged from the crisis, exploring what these reveal about the nature of the reforms implemented since the end of the country's civil war. In turn, it explores what these suggest for future SSR, which continues to be a core component of the UK’s approach to development and overseas capacity-building.

  14. Changes in precipitating snow chemistry with location and elevation in the California Sierra Nevada

    Science.gov (United States)

    Creamean, Jessie M.; Axson, Jessica L.; Bondy, Amy L.; Craig, Rebecca L.; May, Nathaniel W.; Shen, Hongru; Weber, Michael H.; Pratt, Kerri A.; Ault, Andrew P.

    2016-06-01

    Orographic snowfall in the Sierra Nevada Mountains is an important source of water for California and can vary significantly on an annual basis. The microphysical properties of orographic clouds and subsequent formation of precipitation are impacted, in part, by aerosols of varying size, number, and chemical composition, which are incorporated into clouds formed along the Sierra barrier. Herein, the physicochemical properties and sources of insoluble residues and soluble ions found in precipitation samples were explored for three sites of variable elevation in the Sierra Nevada during the 2012-2013 winter season. Residues were characterized using a suite of physicochemical techniques to determine the size-resolved number concentrations and associated chemical composition. A transition in the aerosol sources that served as cloud seeds or were scavenged in-cloud and below-cloud was observed as a function of location and elevation. Anthropogenic influence from the Central Valley was dominant at the two lowest elevation sites (1900 and 2200 m above mean sea level (AMSL)), whereas long-range transported mineral dust was a larger contributor at the highest elevation site where cleaner conditions were observed (2600 m AMSL). The residues and soluble ions observed provide insight into how multiple aerosol sources can impact cloud and precipitation formation processes, even over relatively small spatial scales. The transition with increasing elevation to aerosols that serve as ice nucleating particles may impact the properties and extent of snowfall in remote mountain regions where snowpack provides a vital supply of water.

  15. New Records of Phlebotomine Sandflies (Diptera: Psychodidae at Sierra Nevada de Santa Marta, Colombia

    Directory of Open Access Journals (Sweden)

    Eduar Elías BEJARANO

    2014-09-01

    Full Text Available NUEVOS HALLAZGOS DE FLEBOTOMÍNEOS (DIPTERA: PSYCHODIDAE EN LA SIERRA NEVADA DE SANTA MARTA, COLOMBIAEl componente entomológico de la leishmaniasis ha sido poco estudiado en la Sierra Nevada de Santa Marta, Colombia, incluido el departamento del Magdalena, donde a la fecha están registradas trece especies de Lutzomyia. En la presente nota se informa el hallazgo de tres especies y un subgénero más en la región. Se recolectaron 885 flebotomíneos en Seywiaka y las veredas Las Tinajas y Calabazo, estribaciones de la Sierra Nevada de Santa Marta (117-130 m.s.n.m.. El 84% de los ejemplares se obtuvieron con trampa CDC, el 11% con trampa Shannon y el 5% fueron capturados, en reposo, con un dispositivo eléctrico de succión.  Se identificaron nueve especies, Lu. gomezi, Lu. panamensis, Lu. trinidadensis, Lu. carpenteri, Lu. evansi, Lu. dysponeta, Lu. dubitans, Lu. shannoni, y Lu. micropyga, la más abundante fue Lu. gomezi (69%, seguida por Lu. panamensis (14%. También se recolectaron ejemplares de la serie Lu. osornoi del subgénero Helcocyrtomyia. Entre el material hallado sobresalen Lu. carpenteri, Lu. dubitans y Lu. dysponeta como primeros registros para el departamento del Magdalena, además de Lu. (Helcocyrtomyia sp., que representa el primer hallazgo del subgénero en el Caribe colombiano.

  16. Espacio urbano, espacio del consumo en las crónicas norteamericanas de Justo Sierra

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    Cristina Beatriz Fernández

    2011-01-01

    Full Text Available El objetivo de este trabajo es analizar las crónicas de viaje de Justo Sierra, escritas en ocasión de su visita a los Estados Unidos a finales del siglo XIX, con énfasis en las dedicadas a la ciudad de Nueva York. En ellas, centramos nuestra atención en el registro textual de fenómenos relacionados con la forma en que Sierra percibe la modernidad norteamericana, especialmente significativa en lo que hace a la relación entre economía y sociedad. Por ello, atendemos particularmente la configuración del espacio urbano como un escenario del consumo, y procuramos demostrar cómo la constitución física y simbólica de las ciudades muestra rasgos de parentesco con esos eventos típicos de la época que fueron las ferias y exposiciones, las cuales también son objeto de la prosa de Sierra.

  17. Interactions among wildland fires in a long-established Sierra Nevada natural fire area

    Science.gov (United States)

    Collins, B.M.; Miller, J.D.; Thode, A.E.; Kelly, M.; van Wagtendonk, J.W.; Stephens, S.L.

    2009-01-01

    We investigate interactions between successive naturally occurring fires, and assess to what extent the environments in which fires burn influence these interactions. Using mapped fire perimeters and satellite-based estimates of post-fire effects (referred to hereafter as fire severity) for 19 fires burning relatively freely over a 31-year period, we demonstrate that fire as a landscape process can exhibit self-limiting characteristics in an upper elevation Sierra Nevada mixed conifer forest. We use the term 'self-limiting' to refer to recurring fire as a process over time (that is, fire regime) consuming fuel and ultimately constraining the spatial extent and lessening fire-induced effects of subsequent fires. When the amount of time between successive adjacent fires is under 9 years, and when fire weather is not extreme (burning index classes (unchanged, low, moderate, high). This is in contrast to a recent study demonstrating increasing high-severity burning throughout the Sierra Nevada from 1984 to 2006, which suggests freely burning fires over time in upper elevation Sierra Nevada mixed conifer forests can regulate fire-induced effects across the landscape. This information can help managers better anticipate short- and long-term effects of allowing naturally ignited fires to burn, and ultimately, improve their ability to implement Wildland Fire Use programs in similar forest types. ?? 2008 Springer Science+Business Media, LLC.

  18. El megadeslizamiento del cerro Uritorco, ladera occidental de la Sierra chica de Córdoba

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    Claudio A Carignano

    2014-03-01

    Full Text Available En el extremo norte de la Sierra Chica de Córdoba, sobre el flanco oeste del cerro Uritorco (1.949 m s.n.m., se ha identificado un megadeslizamiento (30°49'55,46"S y 64°29'50,31"O. Los materiales movilizados del frente del escarpe de la falla Sierra Chica, han cubierto parcialmente el granito de Capilla del Monte y los abanicos aluviales pleistocenos del piedemonte. El lóbulo y bloques rotados del deslizamiento conforman un alto topográfico que oficia de límite entre los valles de Punilla (al sur y de Charbonier (al noroeste. Mediante técnicas de procesamiento e interpretación de imágenes satelitales multiespectrales de media (Landsat-ETM y muy alta resolución (GeoEye-1, análisis digital del terreno a partir de modelos de elevación (SRTM y Aster-GDEM y el correspondiente control de campo, se ha delimitado y caracterizado esta megageoforma nunca antes advertida. Dada la elevada sismicidad actual e histórica de la zona y los indicios morfotectónicos que señalan como activas a las fallas Sierra Chica y Pajarillo-Copacabana-Masa, se estima que este deslizamiento posiblemente fue gatillado por un evento sísmico, acontecido en alguna de esas estructuras. Tanto el depósito del deslizamiento como su cicatriz de despegue presentan un significativo grado de erosión hídrica. Por análisis comparativos con otros deslizamientos ya datados y de características similares, situados en el escarpe occidental de las Sierras de San Luis, se le asigna una edad pleistocena medio-tardía. Por su volumen y características (2,1 x109 m³ se estableció que se trata de un megadeslizamiento único en las Sierras de Córdoba y constituye uno de los deslizamientos de mayor tamaño entre los registrados hasta el presente en Argentina.

  19. Faja de Deformación La Horqueta, sierra de Velasco, Sierras Pampeanas, NO de Argentina: petrografía, geoquímica, estructuras y significado tectónico

    Directory of Open Access Journals (Sweden)

    Toselli, A. J.

    2007-12-01

    Full Text Available The La Horqueta Shear Zone (LHSZ is the sixth shear zone recognized in the Sierra de Velasco, Sierras Pampeanas, NW Argentina. This shear zone separates two types of metagranitoids of contrasting petrographical and geochemical characteristics: metagranodiorites, outcropping towards the SW, consist in weakly peraluminous biotite-allanite-titanite granodiorites similar to the I-type granitoids of southern Sierra de Velasco and of neighboring ranges that are part of the Famatinian magmatic arc, while metagranites, outcropping towards the NE, consist in strongly peraluminous biotite-muscovite monzogranites identical to the Antinaco Orthogneis of northern Sierra de Velasco, which is part of an inner S-type granitoid belt. The LHSZ, developed from these two protoliths, has a thickness of 1 to 2 km and is composed of protomylonites and mylonites with strong NNW trending and E dipping mylonitic foliation. Cinematic analyses indicates a main transpressive deformational regime with an inverse-sinistral component, accompanied by a subordinate dextral transcurrent component, which possibly placed the two tectonic settings in contact.La Faja de Deformación La Horqueta (FDLH es la sexta faja de cizalla reconocida en la sierra de Velasco, Sierras Pampeanas, NO de Argentina. Esta faja separa dos tipos de metagranitoides de características petrográficas y geoquímicas contrastadas: metagranodioritas, hacia el SO, consisten en granodioritas con biotita-allanita-titanita débilmente peraluminosas que se asemejan a los granitoides tipo I del sur de la sierra de Velasco y de sierras aledañas pertenecientes al arco magmático famatiniano, mientras que los metagranitos, hacia el NE, consisten en monzogranitos con biotita-muscovita fuertemente peraluminosos idénticos al Ortogneis Antinaco del norte de la sierra de Velasco, el cual pertenece a un cinturón de granitoides tipo S interno, respecto del arco famatiniano. La FDLH, desarrollada allí a partir de estos

  20. Patterns of endemism along an elevation gradient in Sierra Nevada (Spain and Lefka Ori (Crete, Greece

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    Fernández-Calzado, R.

    2013-12-01

    Full Text Available Aim: High mountains in the Mediterranean region of Europe are particularly rich in endemic vascular plants. We aimed to compare the altitudinal patterns of vascular plant species richness and the proportion of endemic species in two Mediterranean region: Lefka Ori on the island of Crete (Greece and Sierra Nevada on the Iberian peninsula. Location: Sierra Nevada, Granada (Spain; Lefka Ori, Crete (Greece. Methods: Data from standardised permanent plots settings on summit sites (comprising eight plot sectors, covering the upeermost 10 altitudinal metres of different elevations were used (GLORIA Multi-Summit approach; www.gloria.ac.at. Species numbers, rates of endemic species, and soils temperature were compared by means of ANCOVA and linear regression. Results: The two regions, though climatically similar, showed strikingly different patterns: In Sierra Nevada, the proportion of endemic vascular plants (species restricted to Sierra Nevada showed a stepwise increase from the lowest to the highest summit. In contrast, the proportion of endemic species restricted to Crete was not significantly different between the four summits in Lefka Ori. In both regions the observed trends were largely consistent with the altitudinal distribution of the endemic species obtained from standard floras. Main conclusions: The geographic positions of the two regions, i.e. island versus mainland and the higher elevation of Sierra Nevada are suggested to be the primary causes of the observed differences. The high degree of endemism in the cold environments of Mediterranean mountains’ upper bioclimatic zones indicates a pronounced vulnerability to the impacts of climate change. A continued and intensified species monitoring in the mountains around the Mediterranean basin, therefore, should be considered as a priority research task.Objetivo: Las zonas de alta montaña en la región mediterránea europea son particularmente ricas en plantas vasculares end

  1. 3ro informe del proyecto de investigación MI SIERRA : Gobernanza y usos de la biodiversidad en la Sierra Occidental de Jalisco.

    OpenAIRE

    Bessy, Anouck; Leparquier, Fleur; Bourbousson, Céline; Mercier, Delphine; Bahuchet, Serge

    2016-01-01

    Este informe presenta una parte de los resultados del proyecto de investigación-acción MI SIERRA del CEMCA y del MNHN, lo cual tiene el objetivo desarrollar el seguimiento científico de un proyecto piloto de área protegida en el occidente de México. La primera parte del informe se enfoca en el análisis de la implementación del proyecto en su territorio, y la segunda parte sobre el análisis etnoecológico y socioeconómico de 4 productos y servicios de la región: el café, los dulces de fruta, lo...

  2. Patrones biogeográficos de la avifauna de la Sierra Madre del Sur Biogeographic patterns of the avifauna of the Sierra Madre del Sur

    Directory of Open Access Journals (Sweden)

    Epifanio Blancas-Calva

    2010-08-01

    Full Text Available Analizamos la avifauna de 26 subcuencas de la provincia biótica de la Sierra Madre del Sur y sus relaciones biogeográficas utilizando el análisis de parsimonia de endemismos (PAE. A partir de información distributional de las especies obtenida de la base de datos del Atlas de las aves de México y de la literatura disponible, construimos una matriz de datos para 26 subcuencas y 437 especies. Se obtuvo un cladograma que sugiere la existencia de 3 grupos de subcuencas: el primero agrupa subcuencas de climas áridos, ubicadas geográficamente de norte a sureste en el estado de Oaxaca; el segundo, otras subcuencas de ambientes climáticos subhúmedos, y el tercero, las restantes subcuencas de ambientes climáticos húmedos de mayor complejidad ambiental.We analyzed the avifauna of 26 sub-basins of the Sierra Madre del Sur biotic province and their biogeographical relationships applying a parsimony analysis of endemicity (PAE. Based on the distributional information of the species obtained from the Atlas de las aves de México and published literature, we built a data matrix for 26 sub-basins and 437 species. The single cladogram obtained suggests the existence of three groups of sub-basins:the first with 5 sub-basins from arid environments, geographically located in north-southeastern Oaxaca; the second with another 5 sub-basins form subhumid environments; and the third one with the remaining sub-basins, from humid and environmentally more complex habitats.

  3. Post-orogenic evolution of the Sierras Septentrionales and the Sierras Australes and links to the evolution of the eastern Argentina South Atlantic passive continental margin constrained by low temperature thermochronometry and 2D thermokinematic modeling

    Science.gov (United States)

    Kollenz, Sebastian; Glasmacher, Ulrich Anton; Rossello, Eduardo A.

    2013-04-01

    The eastern Argentina South Atlantic passive continental margin is distinguished by a very flat topography. Out of the so called Pampean flat two mountain ranges are arising. These mountain ranges, the Sierras Australes and the Sierras Septentrionales, are located in the State of Buenos Aires south of the capital Buenos Aires. North of the Sierras Septentrionales the Salado basin is located. The Sierras Septentrionales and the Sierras Australes are also divided by a smaller intracratonic basin. Further in the South the Colorado basin is located. The Sierras Australes is a variscian fold belt originated by strong phases of metamorphosis, but till now it is unclear by how many tectonic phases the area was influenced (Tomezzoli & Vilas, 1999). It consists of Proterozoic to Paleozoic rocks. The Sierras Septentrionales consists mainly of Precambrian crystalline rocks. The Precambrian sequences are overlain by younger Sediments (Cingolani, 2010). The aim is to understand the long-term landscape evolution of the area by quantifiying erosion- and exhumation-rates and by dating ancient rock-uplift-events. Another goal is to find out how the opening of the south atlantic took effect on this region. To fulfill this goal, thermochronological techniques, such as fission-track dating and (U-Th-Sm)/He dating has been applied to samples from the region. Because there was no low-temperature thermochronology done in this area, both techniques were applied on apatites and zircons. Furthermore, numerical modeling of the cooling history has provided the data base for the quantification of the exhumation rates. The first data-set shows clusters of different ages which can be linked to tectonic activities during late Paleozoic times. Also the thermokinematic modeling is leading to new insights of the evolution of both mountain ranges. References: Renata Nela Tomezzoli and Juan Francisco Vilas (1999): Palaeomagnetic constraints on the age of deformation of the Sierras Australes thrust and

  4. Using the MicroASAR on the NASA SIERRA UAS in the Characterization of Arctic Sea Ice Experiment

    Science.gov (United States)

    Zaugg, Evan; Long, David; Edwards, Matthew; Fladeland, Matthew; Kolyer, Richard; Crocker, Ian; Maslanik, James; Herzfeld, Ute; Wallin, Bruce

    2010-01-01

    The MicroASAR is a flexible, robust SAR system built on the successful legacy of the BYU microSAR. It is a compact LFM-CW SAR system designed for low-power operation on small, manned aircraft or UAS. The NASA SIERRA UAS was designed to test new instruments and support flight experiments. NASA used the MicroASAR on the SIERRA during a science field campaign in 2009 to study sea ice roughness and break-up in the Arctic and high northern latitudes. This mission is known as CASIE-09 (Characterization of Arctic Sea Ice Experiment 2009). This paper describes the MicroASAR and its role flying on the SIERRA UAS platform as part of CASIE-09.

  5. Anomalías del campo gravitatorio y magnético terrestre en la sierra de Socoscora, provincia de San Luis

    Directory of Open Access Journals (Sweden)

    J Kostadinoff

    2003-12-01

    Full Text Available La sierra de Socoscora se ubica en forma meridiana y se manifiesta como un escalón al noroeste de la Sierra Grande de San Luis. En la sierra de Socoscora las rocas del basamento están representadas por metamorfitas de alto grado con escasos afloramientos de metabasitas. Las mediciones del campo gravitatorio y magnético indican la presencia de un volumen mayor de estas rocas en su subsuelo. Los excesos de masa en esta sierra se hallan definidas por anomalías gravimétricas de Bouguer (residuales positivas similares a las encontradas en la Sierra Grande de San Luis. La magnetometría indica, a partir de las respuestas positivas, la existencia de rocas máficas con concentraciones anómalas de minerales magnéticos.

  6. The Sierra Nevada-San Joaquin Hydrologic Observatory (SNSJHO): A WATERS Network Test Bed

    Science.gov (United States)

    Fisher, J.; Meng, X.; Rice, R.; Butler, C.; Molotch, N.; Harmon, T. C.; Bales, R.

    2007-12-01

    A mountain-to-valley virtual hydrologic observatory in Central California provides a focus for data and information in support of hydrologic research, a testbed for prototype measurement systems, and guidance for development of measurement and cyber infrastructure in an actual observatory. The multiple rivers and watersheds making up the 60,000 km2 greater San Joaquin drainage are physically disconnected by mountain-front dams that provide flood control, hydropower, seasonal water delivery and recreation. However, the mountain and valley portions are institutionally connected in multiple ways. For example, each year the winter snowpack and watershed conditions determine the magnitude of annual runoff. Errors in snowpack measurements and runoff forecasts have huge economic implications for valley water users. Second, valley flood control, water quality, irrigation demand and hydropower operations have a very strong interest in influencing mountain watershed management. The broader aim of the Sierra Nevada-San Joaquin Hydrologic Observatory is to build research infrastructure and promote research for improving the knowledge base for sound hydrologic management in the Sierra Nevada, San Joaquin Valley and across the Western U.S. In the Sierra Nevada the current focus is on developing spatially distributed instrument clusters that, when blended with remotely sensed data, will improve water balance closure from hillslope to watershed scales. Five instrument clusters at or just above the rain-snow transition are in place and under development. In the San Joaquin Valley, the focus is on sensor systems for observing fertilizer application rates in agriculture, groundwater-surface water exchanges in rivers, and flow and mixing in the confluence zones between the main stem San Joaquin and tributary Merced Rivers. A common digital library and analysis framework further links the mountain and valley portions of the virtual observatory (see https://eng.ucmerced.edu/dev00/snsjno).

  7. The Impact of the West Africa Ebola Outbreak on Obstetric Health Care in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Kim J Brolin Ribacke

    Full Text Available As Sierra Leone celebrates the end of the Ebola Virus Disease (EVD outbreak, we can begin to fully grasp its impact on already weak health systems. The EVD outbreak in West Africa forced many hospitals to close down or reduce their activity, either to prevent nosocomial transmission or because of staff shortages. The aim of this study is to assess the potential impact of EVD on nationwide access to obstetric care in Sierra Leone.Community health officers collected weekly data between January 2014-May 2015 on in-hospital deliveries and caesarean sections (C-sections from all open facilities (public, private for-profit and private non-profit sectors offering emergency obstetrics in Sierra Leone. This was compared to official data of EVD cases per district. Logistic and Poisson regression analyses were used to compute risk and rate estimates. Nationwide, the number of in-hospital deliveries and C-sections decreased by over 20% during the EVD outbreak. The decline occurred early on in the EVD outbreak and was mainly attributable to the closing of private not-for-profit hospitals rather than government facilities. Due to difficulties in collecting data in the midst of an epidemic, limitations of this study include some missing data points.Both the number of in-hospital deliveries and C-sections substantially declined shortly after the onset of the EVD outbreak. Since access to emergency obstetric care, like C-sections, is associated with decreased maternal mortality, many women are likely to have died due to the reduced access to appropriate care during childbirth. Future research on indirect health effects of health system breakdown should ideally be nationwide and continue also into the recovery phase. It is also important to understand the mechanisms behind the deterioration so that important health services can be reestablished.

  8. Mechanical Effects of Normal Faulting Along the Eastern Escarpment of the Sierra Nevada, California

    Science.gov (United States)

    Martel, S. J.; Logan, J. M.; Stock, G. M.

    2013-12-01

    Here we test whether the regional near-surface stress field in the Sierra Nevada, California, and the near-surface fracturing that heavily influences the Sierran landscape are a mechanical response to normal faulting along its eastern escarpment. A compilation of existing near-surface stress measurements for the central Sierra Nevada, together with three new measurements, shows the most compressive horizontal stresses are 3-21 MPa, consistent with the widespread distribution of sheeting joints (near-surface fractures subparallel to the ground surface). In contrast, a new stress measurement at Aeolian Buttes in the Mono Basin, east of the range front fault system, reveals a horizontal principal tension of 0.014 MPa, consistent with the abundant vertical joints there. To evaluate mechanical effects of normal faulting, we modeled both normal faults and grabens in three ways: (1) dislocations of specified slip in an elastic half-space, (2) frictionless sliding surfaces in an elastic half-space; and (3) faults in thin elastic beams resting on an inviscid fluid. The different mechanical models predict concave upward flexure and widespread near-surface compressive stresses in the Sierra Nevada that surpass the measurements even for as little as 1 km of normal slip along the eastern escarpment, which exhibits 1-3 km of structural and topographic relief. The models also predict concave downward flexure of the bedrock floors and horizontal near-surface tensile stresses east of the escarpment. The thin-beam models account best for the topographic relief of the eastern escarpment and the measured stresses given current best estimates for the rheology of the Sierran lithosphere. Our findings collectively indicate that the regional near-surface stress field and the widespread near-surface fracturing directly reflect the mechanical response to normal faulting along the eastern escarpment. These results have broad scientific and engineering implications for slope stability

  9. An estimate of hernia prevalence in Sierra Leone from a nationwide community survey

    Science.gov (United States)

    Patel, Hiten D; Groen, Reinou S; Kamara, Thaim B; Samai, Mohamed; Farahzad, Mina M; Cassidy, Laura D; Kushner, Adam L; Wren, Sherry M

    2016-01-01

    Purpose A large number of unrepaired inguinal hernias is expected in sub-Saharan Africa where late presentation often results in incarceration, strangulation, or giant scrotal hernias. However, no representative population-based data is available to quantify the prevalence of hernias. We present data on groin masses in Sierra Leone to estimate prevalence, barriers to care, and associated disability. Methods A cluster randomized, cross-sectional household survey of 75 clusters of 25 households with 2 respondents each was designed to calculate the prevalence of and disability caused by groin hernias in Sierra Leone using a verbal head-to-toe examination. Barriers to hernia repairs were assessed by asking participants the main reason for delay in surgical care. Results Information was obtained from 3645 respondents in 1843 households, of which 1669 (46%) were male and included in the study. In total, 117 males or 7.01% (95% CI 5.64-8.38) reported a soft or reducible swelling likely representing a hernia with four men having two masses. Of the 93.2% who indicated the need for health care, only 22.2% underwent a procedure, citing limited funds (59.0%) as the major barrier to care. On disability assessment, 20.2% were not able to work secondary to the groin swelling. Conclusions The results indicate groin masses represent a major burden for the male population in Sierra Leone. Improving access to surgical care for adult patients with hernias and early intervention for children will be vital to address the burden of disease and prevent complications or limitations of daily activity. PMID:24241327

  10. Support services for survivors of ebola virus disease - Sierra Leone, 2014.

    Science.gov (United States)

    Lee-Kwan, Seung Hee; DeLuca, Nickolas; Adams, Monica; Dalling, Matthew; Drevlow, Elizabeth; Gassama, Gladys; Davies, Tina

    2014-12-19

    As of December 6, 2014, Sierra Leone reported 6,317 laboratory-confirmed cases of Ebola virus disease (Ebola), the highest number of reported cases in the current West Africa epidemic. The Sierra Leone Ministry of Health and Sanitation reported that as of December 6, 2014, there were 1,181 persons who had survived and were discharged. Survivors from previous Ebola outbreaks have reported major barriers to resuming normal lives after release from treatment, such as emotional distress, health issues, loss of possessions, and difficulty regaining their livelihoods. In August 2014, a knowledge, attitude, and practice survey regarding the Ebola outbreak in Sierra Leone, administered by a consortium of partners that included the Ministry of Health and Sanitation, UNICEF, CDC, and a local nongovernmental organization, Focus 1000, found that 96% of the general population respondents reported some discriminatory attitude towards persons with suspected or known Ebola. Access to increased psychosocial support, provision of goods, and family and community reunification programs might reduce these barriers. Survivors also have unique potential to contribute to the Ebola response, particularly because survivors might have some immunity to the same virus strain. In previous outbreaks, survivors served as burial team members, contact tracers, and community educators promoting messages that seeking treatment improves the chances for survival and that persons who survived Ebola can help their communities. As caregivers in Ebola treatment units, survivors have encouraged patients to stay hydrated and eat and inspired them to believe that they, too, can survive. Survivors regaining livelihood through participation in the response might offset the stigma associated with Ebola.

  11. The Influence of Antecedent Soil Moisture on Springtime Runoff in the Sierra Nevada Mountains

    Science.gov (United States)

    Flint, A. L.; Flint, L. E.; Dettinger, M. D.

    2009-12-01

    As the changing climate influences precipitation, air temperature, and snowmelt, measurements in the Sierra Nevada are illustrating the contribution of antecedent soil moisture on the timing and volume of springtime runoff. Delays in runoff correspond to low antecedent soil moisture from the preceding fall when snow fell on dry soil. In the Tuolumne River streamgage at the Little Grand Canyon just above Hetch Hetchy reservoir, no delay occurred between runoff and snowmelt in 2007 when the soil was wetter due to a cooler summer and fall rains. However, a 26-day delay in runoff was observed after the onset of snowmelt in 2008 when the soil was drier than the preceding fall at the time of the first snowfall due to a hotter and drier summer. If soils are dry prior to snowfall then the soil moisture is first replenished by springtime snowmelt, which not only delays runoff, but also reduces runoff volume to less than that estimated from snow pack. Typical runoff forecasts rely heavily on snow survey data and snowpack conditions, and the exclusion of soil moisture data could lead to an overestimate of the amount of runoff and compromise reservoir operations. In an average snowfall year, for example, the Kaweah Basin in the southern Sierra Nevada could lose as much as 20 percent of its snow water equivalent and the Merced Basin could lose 12 percent of its snow water equivalent simply to recharge soil moisture. Analyses of measured soil moisture in the Sierra Nevada, corresponding high elevation streamflow records, regional hydrologic modeling, and analysis of future climate projections to define the nature of summer and fall temperature and precipitation, will be used to illustrate the important role antecedent soil moisture plays in the timing and volume of springtime runoff in a changing climate.

  12. Representación de las propiedades de las aguas mineromedicinales de la Sierra del Rosario.

    Directory of Open Access Journals (Sweden)

    Margaret Suárez Muñoz

    2005-01-01

    Full Text Available La representación gráfica y el uso de Sistemas de Información Geográfica (SIG, ha permitido que los datos de diferentes recursos de aguas minerales de la Sierra del Rosario sean mostrados de forma resumida y que ofrezcan mayor claridad para usuarios experimentados o no, que precisen este tipo de información. En este trabajo con los datos de diferentes campañas de muestro realizadas en la Sierra del Rosario, han sido representadas, según su distribución geográfica algunas de las propiedades físico-químicas, con repercusión directa en las propiedades terapéuticas, de éstas aguas. El trabajo tiene como objetivo mostrar parte de la labor que se ha realizado en la Sierra del Rosario, completando la información existente en esta zona tan rica en recursos termales y procesándola para realizar un atlas de los recursos de la zona y con posterioridad del resto de los recursos del país. En su elaboración se utilizaron diferentes programas hidrogeoquímicos como el SACAN y el HIDROGEOQUIM, paquete de Microsoft Office 98 para Windows y el MAPINFO 6.5 como Sistema de Información Geográfica (SIG. El resultado final muestra diferentes mapas con representaciones de las propiedades de estas aguas, que fueron agrupadas según sus características, para brindar una información gráfica muy útil para la posterior utilización las mismas.

  13. REGIONAL HYDROLOGY OF THE NOPAL I SITE, SIERRA DE PENA BLANCA, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Rodriguez-Pineda; P. Goodell; P.F. Dobson; J. Walton; R. Oliver; De La Garza; S. Harder

    2005-07-11

    The U.S. Department of Energy sponsored the drilling of three wells in 2003 near the Nopal I uranium deposit at the Sierra Pena Blanca, Chihuahua, Mexico. Piezometric information is being collected to understand groundwater flow at local and regional levels as part of an ongoing natural analogue study of radionuclide migration. Water level monitoring reported at these and other wells in the region is combined with archival data to provide a better understanding of the hydrology at Nopal I. Initial results suggest that the local hydrology is dependent on the regional hydrologic setting and that this groundwater system behaves as an unconfined aquifer. The region is dominated by an alternating sequence of highlands and basins that step down from west to east. The Sierra de Pena Blanca was downdropped from the cratonic block to the west during Cenozoic extension. The Nopal I area is near the intersection of two large listric faults, and the questa of ash flow tuffs that hosts the deposit has been subjected to complex structural events. The Pena Blanca Uranium District was originally characterized by 105 airborne radiometric anomalies, indicating widespread uranium mineralization. The Nopal I uranium deposit is located in the Sierra del Pena Blanca between the Encinillas Basin to the west, with a mean elevation of 1560 m, and the El Cuervo Basin to the east, with a mean elevation of 1230 m. The Nopal I + 10 level is at an intermediate elevation of 1463 m, with a corresponding groundwater elevation of approximately 1240 m. The regional potentiometric surface indicates flow from west to east, with the El Cuervo Basin being the discharge zone for the regional flow system. However, it appears that the local groundwater potential beneath the Nopal I site is more in accordance with the water table of the El Cuervo Basin than with that of the Encinillas Basin. This might indicate that there is limited groundwater flow between the Encinillas Basin and the Nopal I area.

  14. Gravity change from 2014 to 2015, Sierra Vista Subwatershed, Upper San Pedro Basin, Arizona

    Science.gov (United States)

    Kennedy, Jeffrey R.

    2016-09-13

    Relative-gravity data and absolute-gravity data were collected at 68 stations in the Sierra Vista Subwatershed, Upper San Pedro Basin, Arizona, in May–June 2015 for the purpose of estimating aquifer-storage change. Similar data from 2014 and a description of the survey network were published in U.S. Geological Survey Open-File Report 2015–1086. Data collection and network adjustment results are presented in this report, which is accompanied by a supporting Web Data Release (http://dx.doi.org/10.5066/F7SQ8XHX). Station positions are presented from a Global Positioning System campaign to determine station elevation.

  15. Thermal alteration of water extractable organic matter in climosequence soils from the Sierra Nevada, California

    Science.gov (United States)

    Santos, Fernanda; Russell, David; Berhe, Asmeret Asefaw

    2016-11-01

    In the next decades, the influence of wildfires in controlling the cycling and composition of soil organic matter (SOM) globally and in the western U.S. is expected to grow. While the impact of fires on bulk SOM has been extensively studied, the extent at which heating of soil affects the soluble component of SOM remains unclear. Here we investigated the thermal transformations of water-extractable organic matter (WEOM) by examining the changes in the distribution of carbon (C) functional groups in WEOM from soils heated at low and intermediate temperatures. WEOM (exported from soils to rivers in the Sierra Nevada and beyond.

  16. Who cares for former child soldiers? Mental health systems of care in sierra leone.

    Science.gov (United States)

    J Song, Suzan; van den Brink, Helene; de Jong, Joop

    2013-10-01

    While numerous studies on former child soldiers (FCS) have shown mental health needs, adequate services are a challenge. This study aimed to identify priorities, barriers and facilitators of mental health care for Sierra Leonean FCS. Thematic analysis was done on 24 qualitative interviews with participants from diverse sectors. Priorities of mental distress, substance abuse, and gender-based violence were common among FCS clients. Barriers were governmental support and communication with other providers. Perceived facilitators of care were primary- and secondary-level interventions. A public mental health model would feasibly build upon local, culturally embraced interventions, targeting local priorities and reducing barriers to care.

  17. IXTLAMATKI VERSUS NAHUALLI. CHAMANISMO, NAHUALISMO Y BRUJERÍA EN LA SIERRA NEGRA DE PUEBLA

    OpenAIRE

    Antonella Fagetti

    2010-01-01

    Las características de ixtlamatki y nahualli, como agentes del bien y del mal en el imaginario de los nahuas de Tlacotepec de Díaz, Puebla, constituyen el punto de partida de la reflexión sobre las relaciones que privan entre el chamanismo, el nahualismo y la brujería, como parte del sistema simbólico-mágico-religioso implicado en la trama de la vida y la muerte. El caso de los nahuas de la Sierra Negra nos permite establecer un conjunto de homologías y diferencias entre estas tres grandes ca...

  18. Diurnal raptors in the fragmented rain forest of the Sierra Imataca, Venezuela

    Science.gov (United States)

    Alvarez, E.; Ellis, D.H.; Smith, D.G.; LaRue, C.T.; Bird, David M.; Varland, Daniel E.; Negro, Juan Jose

    1996-01-01

    The rain forest of the Sierra Imataca in eastern Venezuela has been subjected to extensive deforestation for pastures and agricultural settlements. In the last decade the opening of access roads combined with intensified logging and mining activities have fragmented a significant portion of the remaining forest. We noted local distribution and habitat use for 42 species of diurnal raptors observed in affected areas in this region. We observed some raptors considered as forest interior species and other open country species foraging and roosting in man-made openings inside the forest.

  19. Practical aspects of mobilising property tax: experience in Sierra Leone and Malawi

    Directory of Open Access Journals (Sweden)

    Paul Fish

    2015-08-01

    Full Text Available Much literature has been written about the appeal of property tax as a stable source of revenue for subnational governments in developing countries. Building on this significant background of literature is the author’s practical experience working in local government institutions within both Sierra Leone and Malawi. This article relates to the development and testing of a process of mobilizing the internally generated property tax revenues of local governments, and reports on the results of that process, and the challenges and lessons learned.

  20. Integration of the Watcher Telescope into the Sierra Stars Observatory Network – Lessons Learned for GLORIA

    Directory of Open Access Journals (Sweden)

    Martin Topinka

    2013-01-01

    Full Text Available The UCD Watcher robotic telescope is planning to participate in the Sierra Stars Observatory Network (SSON, a US-based organisation that provides astronomical images upon request to subscribing users, who are typically either amateurs or university/college students. Implementing the tasks required for the integration of Watcher to SSON, such as remote scheduling, file transfer, image quality validation and the provision of meteorological information, have provided useful experience for the GLORIA project. It has also become apparent that managing user expectations will be important for GLORIA.

  1. Seroprevalence of Toxoplasma gondii in females alpacas of SAIS Pachacutec, Central Sierra of Peru

    OpenAIRE

    De La Cruz C., Hernán; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Chávez V., Amanda; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima.; Casas A., Eva; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Li E., Olga; Laboratorio de Patología Clínica y Biología Molecular, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima, Perú.

    2011-01-01

    The objective of this study was to determine the seroprevalence of antibodies against Toxoplasma gondii in alpacas at the production unit of Cuyo, part of SAIS Pachacutec in the Central Sierra of Peru. Blood samples were collected in 258 female alpacas in January 2003. Sera were tested against T. gondii antibodies by the Indirect Immunoflorescence test (IFI). The results showed that 8.5 ± 3.4% (22/258) of animals had antibodies against the parasite. This frequency is lower than in other alpac...

  2. The Ebola virus disease outbreak and the mineral sectors of Guinea, Liberia, and Sierra Leone

    Science.gov (United States)

    Bermúdez-Lugo, Omayra; Menzie, William D.

    2015-01-01

    The mineral sector plays a key role in the economies of Guinea, Liberia, and Sierra Leone. The onset of the Ebola virus disease (EVD) outbreak in early 2014, together with changes in mineral market conditions, raised questions regarding the status of mining operations and of mineral development and exploration projects in all three countries. Mineral projects were the underpinnings of World Bank short-term forecasts of increases in gross domestic product (GDP) for all three countries and were expected to be the basis of future economic growth. The significant delay or cancellation of these projects could result in a major economic setback for all three countries.

  3. Bodies in action. Culture and body skills in post-conflict Sierra Leone

    OpenAIRE

    Niet, de, M.

    2010-01-01

    This book is about human body movement and culture. The body skills of a sample of Sierra Leoneans are analyzed in terms of acquisition of the skills, the importance of learning these skills to become part of a community and the physical consequences of the activities. It focuses on skills in football as well as skills used in mundane daily life. Using a combination of technical and anthropological research methods, it offers an example of how to study human body movement in a real-life setti...

  4. LOS HOSPITALES DE LA SIERRA TARASCA EN EL SIGLO XVII; SU IMPORTANCIA URBANO-ARQUITECTONICA

    OpenAIRE

    GUTIERREZ EQUIHUA, ANGEL

    2012-01-01

    El presente trabajo contiene los resultados de una investigación urbano-arquitectónica acerca de los hospitales de La Inmaculada Concepción de La Sierra tarasca, haciendo énfasis en el siglo XVII, una región montañosa del centro del estado de Michoacán, que se encuentra ubicado al occidente de México. El estudio está enfocado a los asentamientos existentes hasta hoy, que durante aquella centuria pertenecieron a las parroquias de Aranza, Sevina y Capacuaro, los cuales aparte de ...

  5. Vertical Distribution of Ozone and Nitric Acid Vapor on the Mammoth Mountain, Eastern Sierra Nevada, California

    OpenAIRE

    2002-01-01

    In August and September 1999 and 2000, concentrations of ozone (O3) and nitric acid vapor (HNO3) were monitored at an elevation gradient (2184–3325 m) on the Mammoth Mountain, eastern Sierra Nevada, California. Passive samplers were used for monitoring exposure to tropospheric O3 and HNO3 vapor. The 2-week average O3 concentrations ranged between 45 and 72 ppb, while HNO3 concentrations ranged between 0.06 and 0.52 μg/m3. Similar ranges of O3 and HNO3 were determined for 2 years of the study....

  6. El programa de abasto rural y la seguridad alimentaria en la Región Sierra de Chiapas

    OpenAIRE

    2014-01-01

    La crisis e inseguridad alimentaria es un hecho que está vulnerando a muchos sectores de la población en nuestro país. En el presente artículo se analiza el fenómeno de la seguridad alimentaria desde la perspectiva de la distribución y acceso a los productos básicos, en la Región Sierra (actualmente denominada como región Sierra Mariscal) del estado de Chiapas. Se abordan algunos de los programas de gobierno que se han implementado con el propósito de garantizar la seguridad alimentaria de lo...

  7. La estructura ándica de las Sierras Pampeanas basada en los mecanismos focales de terremotos en su región noroeste The Andean structure of the Sierras Pampeanas based on earthquake focal mechanisms in their northwestern region

    Directory of Open Access Journals (Sweden)

    Patricia Alvarado

    2010-12-01

    Full Text Available El modelado de formas de ondas sísmicas de banda ancha de redes globales y de Chile para dos terremotos corticales moderados de la región noroeste de las Sierras Pampeanas ha permitido caracterizar sus mecanismos focales, profundidades hipocentrales y características sismotectónicas. El terremoto de magnitud Mw 5.8 del 28 de mayo de 2002 localizado en el flanco oriental de la sierra de Velasco y el terremoto Mw 6.2 del 7 de setiembre de 2004 con epicentro en la parte sudoccidental de la sierra de Ambato muestran profundidades focales someras de 10 y 8 km, respectivamente. Estos resultados combinados con la sismicidad histórica de la región permiten esbozar la estructura profunda de las Sierras Pampeanas en la región estudiada. El análisis sismológico efectuado en forma conjunta con la interpretación de la estructura superficial y los estudios neotectónicos previos permiten descartar mecanismos extensionales o de deformación mediante desplazamiento de rumbo como los responsables de la estructuración actual de las sierras de Ambato y Velasco. Se realiza la comparación entre el vector de velocidad de convergencia entre las placas de Nazca y Sudamericana, y los vectores relativos de velocidades de GPS en la región de estudio con la sumatoria del tensor momento sísmico para la mayor liberación de energía sísmica de sismos corticales ocurridos en la región en los últimos 30 años. Esta comparación predice una rotación horaria de 50º del eje de máxima compresión (eje P promedio respecto de la orientación hacia el noreste de la convergencia mencionada y muestra una importante partición de la deformación. Se interpreta que esta partición está controlada por la fábrica eopaleozoica del basamento, que ha regulado la orientación y vergencia de las fallas andinas.Modeling of broadband seismic waveforms recorded by global and Chilean networks for two moderate crustal earthquakes of the northwestern Sierras Pampeanas shows

  8. Radiometric Observations of Supercooled Liquid Water within a Split Front over the Sierra Nevada.

    Science.gov (United States)

    Heggli, Mark F.; Reynolds, David W.

    1985-11-01

    A storm bearing close structural resemblance to a katafront was observed from the ground with microwave radiometry and a vertically pointing Ka-band radar over the Sierra Nevada of California. The onset and duration of supercooled liquid water was determined and matched to a split front model used to describe the synoptic features of a katafront. Results indicate that prior to the passage of the upper front no supercooled liquid water was observed. This portion of the storm provided the deepest cloud and coldest cloud tops. Supercooled liquid water was most prevalent after the upper front passage, and persisted until the suspected surface front passage. The duration of measured supercooled water was 16 hours.This information broadens the knowledge regarding the presence of supercooled liquid water, and thus possible seeding potential, within winter storms so that treatment can be confined to the period of storms amenable to cloud seeding. Future studies may well confirm the ease with which these periods can be predicted on an operational basis in the Sierra Nevada.

  9. Structure et stratigraphie du secteur oriental de la Sierra Almijara (zone alpujarride, Cordilleres Betiques

    Directory of Open Access Journals (Sweden)

    Sanz Galdeano, C.

    1986-10-01

    Full Text Available La série stratigraphique de la Sierra Almijara est formée. a sa base, par des schistes et des quarzites, sur lesquels se trouve une puissante formation divisée en trois terms. Deux d’entre eux sont de marbres et ils sont séparés par un troisème de schistes, calcoschistes et marbres. La structure montre des plis serrés, de direction N70 et d'autres qui semblent postérieurs de direction NNW-SSE. D'importants décrochements et failles inverses les coupent. On distingue seulement une nappe dans la zone étudiée: celle d’Almijara.
    La serie estratigráfica de Sierra Almijara está formada en su base por esquistos y cuarcitas sobre los que se sitúa una potente formación dividida en tres tramos. Dos de ellos son de mármoles y están separados por otro de esquistos, calcosquistos y mármoles. La estructura muestra apretados pliegues de dirección N70 y otros aparentemente posteriores de dirección NNW-SSE. Importantes fallas de desgarre e inversas los cortan. Sólo se distingue un manto en el área estudiada: el de Almijara

  10. Fumio Matsumura--accomplishments at the University of California, Davis, and in the Sierra Nevada Mountains.

    Science.gov (United States)

    Seiber, James N

    2015-05-01

    Fumio Matsumura joined the University of California, Davis, faculty in 1987 where he served as founding director of the Center for Environmental Health Sciences, associate director of the U.C. Toxic Substances Research and Teaching Program, and chair of the Department of Environmental Toxicology. He was an active affiliate with the NIEHS-funded Superfund Basic Research Program and the NIH Comprehensive Cancer Center. He was in many instances a primary driver or otherwise involved in most activities related to environmental toxicology at Davis, including the education of students in environmental biochemistry and ecotoxicology. A significant part of his broad research program was focused on the long range transport of chemicals such as toxaphene, PCBs and related contaminants used or released in California to the Sierra Nevada mountains, downwind of the urban and agricultural regions of the state. He hypothesized that these chemical residues adversely affected fish and wildlife, and particularly the declining populations of amphibians in Sierra Nevada streams and lakes. Fumio and his students and colleagues found residues of toxaphene and PCBs at higher elevations, an apparent result of atmospheric drift and deposition in the mountains. Fumio and his wife Teruko had personal interests in, and a love of the mountains, as avid skiers, hikers, and outdoor enthusiasts.

  11. La cruz en la joyería tradicional salmantina: Sierra de Francia y Candelario

    Directory of Open Access Journals (Sweden)

    Cea Gutiérrez, Antonio

    1996-12-01

    Full Text Available The author discusses the iconography of a type of cross, the jeweled cross, in the vast and complex context of traditional clothing in the área of Sierra de Francia and Candelario (Salamanca province, Spain. Upon the basis of fieldwork, archival documents —which date from the late 1500's through the 1870's—, and the observation of the witnessing piece, he analyze from an ethnohistorical perspective the material and formal aspects of this cross as well as its associations with various characters of the Catholic pantheon. A comprehensive knowledge of the jewel illuminates a great deal of the society that treasured it.Se estudia la cruz-joya dentro del vasto y complejo ámbito de la indumentaria tradicional en el área de la Sierra de Francia y Candelario (Salamanca. A través de la documentación de archivo, que abarca desde los últimos años del siglo XVI hasta la octava década del XIX, el trabajo de campo y la observación de la pieza-testigo se analizan —desde una óptica etnohistórica— los aspectos materiales y formales de la cruz y sus variantes advocacionales. Con el conocimiento de esta joya pretendemos el de esta sociedad que la disfrutó.

  12. Ecofeminismo, mujeres y desarrollo sustentable: el caso de la Sierra de Santa Rosa en Guanajuato

    Directory of Open Access Journals (Sweden)

    Abril Saldaña Tejeda

    2015-01-01

    Full Text Available en este artículo se explora la participación de las mujeres en el Programa de Desarrollo Sustentable Sierra de Santa Rosa, en Guanajuato, de 2001 a 2011. Se expone la aportación del ecofeminismo para la noción de desarrollo sustentable, y para entender el vínculo entre la naturaleza y las mujeres. Se argumenta que la historia de la región, en específico el auge de la industria minera durante la Colonia, es un buen punto de partida para entender los problemas ambientales de la sierra y para visualizar el vínculo entre las estructuras que funcionan en detrimento del medio ambiente y de las mujeres. Así como también que dicho programa tuvo un efecto positivo en la participación social de las mujeres. Sin embargo, existen todavía retos importantes que se manifiestan en estructuras ideológicas, que impiden la participación de las mujeres como líderes y no sólo como trabajadoras, en las condiciones de pobreza que obstaculizan un verdadero compromiso con la sustentabilidad.

  13. Diamanti e sviluppo Un’analisi critica degli stereotipi sui minatori della Sierra Leone

    Directory of Open Access Journals (Sweden)

    Lorenzo D’Angelo

    2015-06-01

    Full Text Available In the last decade, the Sierra Leone’s diamond mines have been the focus of an intense debate among analysts and experts of the development. Two main interrelated issues have been at stake in this debate: first, to understand the economic and political reasons that had supported the civil war from 1991 to 2002 and, second, to understand how to convert a potential “conflict commodity” in a resource for peace and prosperity. In this paper, I intend to highlight some recurring stereotypes of this debate. In particular, I will focus on a constellation of representations that depict the artisanal miners either as workers poorly organized and prone to irrational economic behavior, or as workers subjected to forms of exploitation akin to slavery. Based on fieldwork conducted in the diamond mining areas of Sierra Leone (2007-2011, this article intends to analyze the main forms of working organization and distribution of earnings among the miners. By challenging some stereotypes characterizing the development discourse, my aim is to show the cultural complexity and the historical density of the practices through which the miners face the risks and uncertainties of their job.

  14. Renealmia alpinia (Rottb.: Maas (Zingiberaceae: planta comestible de la Sierra Norte de Puebla (México

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    Macía, Manuel J.

    2002-06-01

    Full Text Available The edible fruits of Renealmia alpinia are highly valued in the Sierra Norte de Puebla (México where they are managed at a household level. The plant is wild in the región, although a rare species. The aril of the fruit is the edible part. After harvesting, the aril is extracted fresh and processed for local consumption. Sometimes the fruits are commercialized in tradicional markets. Only 19% of the total weight of the fruits is used for food.Los frutos comestibles de Renealmia alpinia son muy apreciados en la Sierra Norte de Puebla (México, en donde son manejados a nivel familiar. La planta crece silvestre en la región, aunque es una especie poco frecuente. La parte comestible es el arilo de los frutos. Tras la cosecha, se extrae en fresco el arilo y se procesa para su consumo familiar. Ocasionalmente los frutos se comercializan en los mercados tradicionales. Solamente el 19 % del peso total de los frutos se aprovecha para alimentación.

  15. NUEVOS HALLAZGOS DE FLEBOTOMÍNEOS (DIPTERA: PSYCHODIDAE EN LA SIERRA NEVADA DE SANTA MARTA, COLOMBIA

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    Eduar Elías BEJARANO

    2015-01-01

    Full Text Available Los insectos relacionados con la transmisión de los patógenos causantes de las leishmaniasis han sido poco estudiados en la Sierra Nevada de Santa Marta, Colombia, incluido el departamento de Magdalena, donde a la fecha están registradas trece especies del género Lutzomyia . En la presente nota se informa el hallazgo de tres especies y un subgénero adicionales en la región. Se recolectaron 885 flebotomíneos en Seywiaka y las veredas Las Tinajas y Calabazo, estribaciones de la Sierra Nevada de Santa Marta ( 117-130 m s.n.m.. El 84 % de los ejemplares se obtuvieron con trampa CDC, el 11 % con trampa Shannon y el 5 % fueron capturados, en reposo, con un dispositivo eléctrico de succión. Se identificaron nueve especies, Lu. gomezi , Lu. panamensis , Lu. trinidadensis , Lu. carpenteri , Lu. evansi , Lu. dysponeta, Lu. dubitans , Lu. shannoni , y Lu. micropyga , la más abundante fue Lu. gomezi (69 %, seguida por Lu. panamensis (14 %. También se recolectaron ejemplares de la serie Lu. osornoi del subgénero Helcocyrtomyia . Entre el material hallado sobresalen Lu. carpenteri , Lu. dubitans y Lu. dysponeta como primeros registros para el departamento del Magdalena, además de Lu. (Helcocyrtomyia sp., que representa el primer informe del subgénero en el Caribe colombiano.

  16. Increasing long-wavelength relief across the southeastern flank of the Sierra Nevada, California

    Science.gov (United States)

    Bennett, R. A.; Fay, N. P.; Hreinsdóttir, S.; Chase, C.; Zandt, G.

    2009-09-01

    A high degree of correlation between present-day relative rock uplift measured using continuous GPS geodesy and spatially averaged surface elevations suggests that long-wavelength topographic relief is presently increasing along the southeastern flank of the Sierra Nevada range and within an adjacent portion of the northern Basin and Range province. Current estimates for erosion rate are an order of magnitude smaller than the relative rates determined by geodesy. Thus, although the uplift serves to enhance long-wavelength relief, it cannot be explained entirely as an isostatic response to erosion. If uplift rates have been constant through time, the duration over which the uplift could have been active (Sierra are evolving with time. According to either hypothesis, vertical surface motions may have slowly accelerated since ~mid-Pliocene time. Several possible mechanisms for progressive reduction of EET may be attributable to thermo-mechanical disequilibrium that began with the removal of an ultramafic root from the Sierran batholith during late Miocene or early Pliocene time. Specific mechanisms for ongoing enhancement of loads are less obvious. Based on these results, we suggest that dense networks of long-running continuous GPS stations around the world currently represent an underutilized resource for studies of orogenesis and upper mantle processes.

  17. Lead poisoning in a calf from the mining area of Sierra Madrona and Alcudia Valley

    Directory of Open Access Journals (Sweden)

    J Rodríguez-Estival

    2014-01-01

    Full Text Available Se notifica el primer caso registrado de intoxicaci n por plomo (Pb en un ternero del antiguo distrito minero de Sierra Madrona y el Valle de Alcudia (Espa a, que apareci en una finca ganadera con restos visibles de antiguas activides mineras en los terrenos circundantes. El nivel de Pb en sangre detectado en el animal fue de 311 g/dL, y estuvo asociado a diversos s ntomas de intoxicaci n cl nica por Pb, que incluyen par lisis severa, p rdida de sensibilidad en los cuartos traseros e incoordinaci n. Los suelos, las plantas y los puntos de agua presentes en la finca mostraron niveles de Pb por encima de los valores umbral, siendo considerados como suelos altamente contaminados, pastos t xicos para el ganado y agua no potable para el consumo humano. Estos datos indican que la contaminaci n por Pb implica un riesgo para la salud del ganado criado en la zona minera de Sierra Madrona y el Valle de Alcudia.

  18. Measured black carbon deposition on the Sierra Nevada snow pack and implication for snow pack retreat

    Directory of Open Access Journals (Sweden)

    O. L. Hadley

    2010-04-01

    Full Text Available Modeling studies show that the darkening of snow and ice by black carbon (BC deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition on the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  19. Measured black carbon deposition on the Sierra Nevada snow pack and implication for snow pack retreat

    Directory of Open Access Journals (Sweden)

    O. L. Hadley

    2010-08-01

    Full Text Available Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  20. Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.; Cliff, S.S.; Ramanathan, V.

    2010-01-12

    Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  1. Chemical and isotopic study of thermal springs and gas discharges from Sierra de Chiapas, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Nencetti, A; Tassi, F; Vaselli, O [Department of Earth Sciences, Florence (Italy); Macias, J. L [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, D.F. (Mexico); Magro, G [CNR-Institute of Geosciences and Earth Resources, Pisa (Italy); Capaccioni, B [Institute of Volcanology and Geochemistry, Urbino (Italy); Minissale, A [CNR-Institute of Geosciences and Earth Resources, Florence (Italy); Mora, J. C [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, D.F. (Mexico)

    2005-01-15

    Thermal water and gas discharges south-east of El Chichon volcano, Mexico are associated mainly with NW-SE oriented fault systems. Spring discharges include i) waters with Na-Cl composition and TDS>3000 mg/L; ii) waters with Ca-SO{sub 4} composition and TDS values between 1400 and 2300 mg/L; iii) waters with Na-Cl composition and TDS of 800 to 2400 mg/L and sulphate content up to 650 mg/L and iv) waters with Ca-HCO{sub 3} composition and low salinity (TDS <250mg/L). Most of these waters are associated with free-gas discharges of N{sub 2} (up to 93 % by vol.), CO{sub 2} (2.4 to 31.2 % by vol.) and Ar (up to 1.25 % by vol.) with a predominant meteoric origin. H{sub 2}S is present only in gas samplers collected at El Azufre (up to 1.1 % by vol.). The {delta}13C CO{sub 2} values are always below -9.7% (PDB) and suggest a partially biogenic origin for CO{sub 2}. Chemical and isotopic features of spring discharges indicate that fluid circulation in the Sierra de Chiapas is mainly regulated by meteoric waters that tend to infiltrate the upper and middle-Cretaceous carbonate units up to the lower Cretaceous-upper Jurassic evaporitic formations (by Lopez-Ramos, 1982). The latter provide the main source of the species in solution. No evidence for high-to-medium enthalpy systems at depth beneath the Sierra de Chiapas has been found. [Spanish] La Sierra de Chiapas localizada en el Sureste de Mexico, se caracteriza por la presencia de descargas de gas y agua. La mayoria de los manantiales termales se asocian a rocas volcanicas Terciarias a lo largo de fallas regionales con orientacion NOSE. Las descargas termales se dividen en cuatro grupos: i) aguas con composicion Na-Cl y Solidos Disueltos Totales (SDT) >3000 mg/L; ii) aguas con composicion Ca-SO{sub 4} y valores de SDT entre 1400 y 2300 mg/L; iii) aguas con composicion Na-Cl, bajos contenidos de SDT (800 2400 mg/L) y un contenido de sulfato alto (hasta 650 mg/L) y iv) aguas con una composicion Ca-HCO{sub 3} y salinidad baja

  2. TECNOLOGÍA DE CAZA EN LA QUEBRADA DE ANTOFALLA, DEPARTAMENTO ANTOFAGASTA DE LA SIERRA, CATAMARCA / Hunting technology in the Antofalla Valley, Antofagasta de la Sierra Department, Catamarca.

    Directory of Open Access Journals (Sweden)

    Enrique Alejandro Moreno

    2011-12-01

    Full Text Available Las prácticas de cacería de camélidos silvestres han sido relevantes para la reproducción de las poblaciones humanas en los Andes Centro-Sur durante los últimos 12000 años aproximadamente. Para la materialización de esta práctica, son relevantes las armas utilizadas para poder dar muerte a las presas pretendidas. Una alternativa para interpretar el tipo de arma es a través de la información obtenida del análisis de las puntas de proyectil líticas registradas mediantes metodologías disciplinarias. Como caso de estudio utilizamos los datos obtenidos de la prospección intensiva y sistemática desarrollada en la quebrada de Antofalla, ubicada en el Departamento Antofagasta de la Sierra, Provincia de Catamarca, Argentina. Para evaluar las características de esta tecnología nos centraremos en tres grandes aspectos: las características tecno-morfológicas de estos instrumentos, la asignación a distintos tipos de armas y sus posibles asignaciones cronológicas, los espacios donde fueron registrados estos especímenes, en relación con las características de los paisajes cinegéticos.   Palabras clave: Tecnología; cacería; camélidos; armas; paisaje.   Abstract The hunting practice of wild camelids has been relevant for the reproduction of human populations in the South Central Andes for the last 12000 years. An important aspect for the materialization of this practice, are the weapons used in order to kill the alleged preys. In this paper we shall introduce the different weapons used by human populations, mainly, through the information obtained from the analysis of of lithic projectile points. As a case study we will retake the information obtained from the intensive and systematic prospection developed at the Antofalla ravine, located in the Departamento Antofagasta de la Sierra, Provincia de Catamarca. In order to evaluate the features of this technology, we will focus on three aspects: the techno-morphological characteristics

  3. Flora útil de los cafetales en la Sierra Norte de Puebla, México Useful plants of the Sierra Norte de Puebla, Mexico

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    Miguel Ángel Martínez

    2007-06-01

    Full Text Available Los cafetales de la Sierra Norte de Puebla son agroecosistemas variados en composición y estructura, donde se pueden encontrar especies vegetales cultivadas y silvestres, nativas e introducidas, y cuya diversidad florística está estrechamente ligada a las condiciones sociales, económicas y ecológicas en las que se inserta la producción del café. En la última década el cultivo de esta planta ha estado en crisis debido a los bajos precios del producto; sin embargo,los agricultores mantienen los cafetales como fuente de ingreso adoptando nuevas estrategias para obtener recursos económicos mediante la introducción o incremento de cultivos de importancia económica, como pimienta, mamey o plantas medicinales, aprovechando la versatilidad y posibilidades de reorganización de estos agroecosistemas. En este trabajo se presenta el inventario de la flora útil encontrada en cafetales de la SNP. A la fecha están registradas 319 especies pertenecientes a 238 géneros y 99 familias; 90 especies son objeto de comercio y pueden representar nuevas fuentes de ingreso; 256 son nativas y 63 introducidas y se han agrupado en 13 categorías antropocéntricas, de las cuales las medicinales y comestibles son las más numerosas.Coffee plantations in the Sierra Norte de Puebla (SNP are agroecosystems with variable composition and structure. These agroecosystems include native and introduced plant species, as well as cultivated and wild ones. Plant diversity in coffee plantations is closely related to the social, economic, and ecological context into which coffee production is inserted. In the last decade, coffee cultivation has been in crisis due to low prices. Nevertheless, farmers of the SNP maintain their plantations as a source of income, with new strategies such as the introduction or increase of plants with economic value, like allspice (Pimenta dioica, mamey (Pouteria sapota, and medicinal plants, taking advantage of the versatility and possibilities

  4. 77 FR 34934 - Foreign-Trade Zone 139-Sierra Vista, AZ; Application for Reorganization Under Alternative Site...

    Science.gov (United States)

    2012-06-12

    ...) by the Sierra Vista Economic Development Foundation, Inc., grantee of FTZ 139, requesting authority... for FTZ designation. The proposed service area is within and adjacent to the Naco U.S. Customs and... requested at this time. In accordance with the Board's regulations, Christopher Kemp of the FTZ Staff...

  5. 77 FR 63328 - Notice of Availability of the Record of Decision for the Chokecherry and Sierra Madre Wind Energy...

    Science.gov (United States)

    2012-10-16

    ... Madre Wind Energy Project and Approved Visual Resource Management Plan Amendment for Public Lands...) announces the availability of the Record of Decision (ROD) for the Chokecherry and Sierra Madre Wind Energy...: The BLM evaluated the potential wind energy development on a broad level to determine...

  6. Trauma Healing in Refugee Camps in Guinea: A Psychosocial Program for Liberian and Sierra Leonean Survivors of Torture and War

    Science.gov (United States)

    Stepakoff, Shanee; Hubbard, Jon; Katoh, Maki; Falk, Erika; Mikulu, Jean-Baptiste; Nkhoma, Potiphar; Omagwa, Yuvenalis

    2006-01-01

    From 1999 to 2005, the Minneapolis-based Center for Victims of Torture (CVT) served Liberian and Sierra Leonean survivors of torture and war living in the refugee camps of Guinea. A psychosocial program was developed with 3 main goals: (1) to provide mental health care; (2) to train local refugee counselors; and (3) to raise community awareness…

  7. Situation Report--Algeria, Bangladesh, Fiji, Gilbert and Ellice Islands, Iran, Jordan, New Zealand, Rwanda, and Sierra Leone.

    Science.gov (United States)

    International Planned Parenthood Federation, London (England).

    Data relating to population and family planning in nine foreign countries are presented in these situation reports. Countries included are Algeria, Bangledesh, Fiji, Gilbert and Ellice Islands, Iran, Jordan, New Zealand, Rwanda, and Sierra Leone. Information is provided under two topics, general background and family planning situation, where…

  8. Examining Internet Usage Demographic Differences and the Relationship between Internet Usage and Business Outcomes in Sierra Leone

    Science.gov (United States)

    Kamara, Mohamed K.

    2013-01-01

    This study utilized the unified theory of acceptance and use of technology (UTAUT) to determine Internet users' perceptions and behavioral intentions to accept Wi-Fi technology deployment in Sierra Leone. The study sought to investigate (a) the Internet usage rates before and after Wi-Fi adaption in Freetown; (b) differences in Internet usage…

  9. 77 FR 45 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List Sierra Nevada...

    Science.gov (United States)

    2012-01-03

    ... them at risk of attack, death, or diseases such as rabies, sarcoptic mange, canine distemper, and... canine distemper, rabies, and sarcoptic mange to Sierra Nevada red fox (Perrine et al. 2010, p. 28... 2011, pp. 54-60), an outbreak of canine distemper or other lethal disease, as well as predation...

  10. Mother Tongue Education and Transitional Literacy in Sierra Leone: Prospects and Challenges in the 21st Century.

    Science.gov (United States)

    Kamanda, Mohamed Combo

    2002-01-01

    Discusses the historical perspective relating to current problems facing mother tongue instruction in Sierra Leone and examines post-independence policies to highlight the institutional bases of mother tongue education and to consider causes of inertia and negative attitudes towards it since independence. (Author/VWL)

  11. An Examination of Primary School Attendance and Completion among Secondary School Age Adolescents in Post-Conflict Sierra Leone

    Science.gov (United States)

    Moyi, Peter

    2013-01-01

    Sierra Leone was ravaged by a civil war between 1991 and 2002. Since the end of the war, it has witnessed an unprecedented increase in school enrollments. Although school enrollment has increased, the number of school age children who are out of school remains high. The focus of international agencies is on children of primary school age, yet a…

  12. Environmental Scan on Education in Sierra Leone with Particular Reference to Open and Distance Learning and Information and Communication Technologies

    Science.gov (United States)

    Alghali, A.M.; Turay, Edward D.A.; Thompson, Ekundayo J.D.; Kandeh, Joseph B.A.

    2005-01-01

    The Sierra Leone National Education Master Plan 1997-2006 deals with all aspects of the formal and non-formal sectors of the education system, providing support for basic education, education for the physically challenged, disadvantaged and gifted learners, women and girls' education, technical/vocational and science education, tertiary education,…

  13. Complete Genome Sequence of an Ebola Virus Isolate Imported from Sierra Leone to Germany Determined by Circle Sequencing

    Science.gov (United States)

    Mengel, Jan Philipp; Lissin, Artur; Biedenkopf, Nadine; Schultze, Tilman; Mannala, Gopala Krishna; Schudt, Gordian; Kann, Gerrit; Wolf, Timo; Eickmann, Markus; Becker, Stephan

    2016-01-01

    We report here a complete genome sequence of Ebola virus Makona from a nonfatal patient sample that originated in Sierra Leone during the last Ebola virus outbreak in West Africa (species Zaire ebolavirus) using a highly accurate circle sequencing (Cir-seq) method.

  14. Dos cartas inéditas de María Lejárraga dirigidas a Gregorio Martínez Sierra

    OpenAIRE

    2008-01-01

    El artículo recoge la publicación de dos cartas inéditas de la correspondencia privada de Gregorio Martínez Sierra. Las cartas están fechadas en 1925 y 1946, respectivamente. Están escritas por María de la O Lejárraga y dirigidas a Gregorio Martínez Sierra. El artículo pretende dejar constancia de la relación profesional y personal que mantuvieron Gregorio Martínez Sierra y María Lejárraga hasta la muerte del dramaturgo en 1947.

  15. Brechas y microbrechas cohesivas en cuarcitas de las sierras de Buenos Aires: Similitudes, diferencias y aproximaciones a su vinculación tectónica

    OpenAIRE

    Armando C. Massabie; Osvaldo E. Nestiero; Sanguinetti, Alicia S.

    2008-01-01

    En las Sierras Septentrionales de Buenos Aires se hallan brechas y microbrechas formadas a expensas de las rocas cuarcíticas del Grupo Sierras Bayas. Son rocas de falla identificadas en afloramientos tanto en las cercanías de la localidad homónima como también en los alrededores de Barker, donde se presentan cuarcitas atribuidas a las formaciones sedimentarias precámbricas integrantes del grupo en la localidad. En las Sierras Australes de Buenos Aires se registran rocas de falla similares, de...

  16. Deformación sísmica reciente de la sierra de Pie de palo, provincia de San Juan

    Directory of Open Access Journals (Sweden)

    Guillermo Monsalvo

    2014-06-01

    Full Text Available En este trabajo se estudia la actividad sísmica en la sierra de Pie de Palo durante enero 2008 a diciembre 2009. Los datos utilizados fueron registrados por 52 estaciones sismológicas de los experimentos SIEMBRA y ESP. En ese período, 149 sismos corticales fueron localizados con magnitudes locales entre 0,8sierra de Pie de Palo con una ausencia en el sector centro occidental de la sierra y valle de Tulum. Además, se observa una distribución de sismos diferente para la corteza situada al norte con respecto al sur de la sierra: en el bloque norte, 52 hipocentros ocurrieron a niveles de corteza media a inferior mientras que en el boque sur, 73 sismos se concentraron principalmente en niveles corticales intermedios. Se observa una buena correlación de la sismicidad con el modelo de corteza local propuesto por Perarnau et al. (2010 posicionándose la mayor ocurrencia de actividad sísmica a profundidades de corteza media a inferior y ninguna determinación sísmica en el nivel más inferior sugiriendo un comportamiento probablemente más dúctil. Un total de 128 mecanismos focales fueron determinados utilizando primeros arribos de ondas P que indican soluciones principalmente de tipo inverso e inverso con componente de rumbo. Los resultados están de acuerdo con un acortamiento cortical en dirección aproximada este-oeste. Además, el estudio de las fuentes sísmicas realizado sugiere una deformación asociada diferente para los bloques que componen a la sierra, tanto en su extensión areal como en profundidad cortical.

  17. Plant endemics to Sierra de Gredos (central Spain: taxonomic, distributional, and evolutionary aspects

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    García, Bernardo

    2008-12-01

    Full Text Available Causes related to a low number of endemics to Sierra de Gredos (central Iberian Peninsula are poorly understood. Taxonomic, distributional and genetic aspects of the 12 endemic taxa (species and subspecies are herein discussed. New populations found in the last years provide new chorological reports and taxa to science. As a result, we extend the distribution range of Pseudomisopates rivas-martinezii and describe a new subspecies (Teucrium oxylepis subsp. Gredense. Genetic variation was investigated by sequencing the ITS (Internal Transcribed Sequence region, which is a widespread nuclear DNA region used to detect significant sequence divergence at the species and population levels. At the species level, only eight endemics to this large mountain range (c. 4,800 km2 indicates both limited speciation events coupled with their persistence, despite the high species richness of the flora of Sierra de Gredos (>2,500. According to the levels of ITS sequence divergence, significant isolation processes may have predated the Quaternary in Sierra de Gredos to account for divergence of the monotypic genus Pseudomisopates from its closest relatives (Misopates, Acanthorrhinum. Isolation of the other seven endemic species from their closest relatives has been a more recent process, as revealed by the limited ITS sequence variation obtained in this study. At the population level, no net nucleotide substitutions were observed between distant populations of the endemic species: Antirrhinum grosii, Astragalus devesae, Centaurea avilae, Dianthus gredensis, Echinospartum barnadesii, Pseudomisopates rivas-martinezii, Santolina oblongifolia. In contrast, the three populations of Sedum lagascae displayed a relatively high number (4 of nucleotide substitutions. These results, together with limited morphological differentiation, may reflect insufficient population isolation of seven of the eight endemic species of Sierra de Gredos in the Quaternary. Recurrent population

  18. Seasonal frost conditions and permafrost regime distribution in the high lands of Sierra Nevada (Spain)

    Science.gov (United States)

    Oliva, Marc; Gómez-Ortiz, Antonio; Salvador-Franch, Ferran; Salvà-Catarineu, Montserrat; Palacios, David; Tanarro, Luis Miguel; Ramos, Miguel

    2016-04-01

    Sierra Nevada, Southern Spain (37°S, 3°W), is the massif including the southernmost permafrost remnants in Europe. Over the last decades the distribution of permafrost in this massif has been examined through a combined approach including geomorphological, geophysical and monitoring studies. The purpose of this communication is to summarize all the studies relating to soil thermal regime in the high lands of Sierra Nevada. A 114.5 m deep borehole was drilled in 2000 in the Veleta summit (3380 m) in order to monitor soil temperatures in the summits of the massif. No permafrost regime was detected, with average temperatures stabilizing at 20 m depth at 2 °C. Seasonal frost conditions were also detected in periglacial landforms such as solifluction lobes and sorted-circles. In the Rio Seco cirque the mean annual temperatures in a solifluction lobe located in a southern glacial cirque of the massif (3005 m) were 3.9 °C at 1 m depth between 2006 and 2012; in the north-exposed San Juan valley, soil temperatures in another solifluction landform (2864 m) were 3.9 °C at 1 m depth between 2003 and 2012. In a sorted-circle located in the high plateau of Cerro de los Machos (3297 m) soil temperatures recorded an average of 1.7 °C at 50 cm depth between 2003 and 2011. The only place where temperatures were permanently negative was inside of the only active rock glacier distributed in the Veleta cirque, on the northern slope of the Veleta peak. Here, the remnants of a small glacier that existed during the Little Ice Age (LIA) are still present in the form of buried ice and permafrost buried under the boulders of this rock glacier. Temperatures averaged 0.2 °C at 1 m depth between 2006 and 2013, with permanently negative temperatures below this level until, at least, 10 m depth. Consequently, seasonal frost is widespread nowadays in most of the Sierra Nevada, with permafrost conditions strongly conditioned by the geomorphological setting and the recent environmental

  19. Diversidad de maiz en la sierra sur de Oaxaca, México: conocimiento y manejo tradicional.

    Directory of Open Access Journals (Sweden)

    Beatriz Rendón-Aguilar

    2015-07-01

    Full Text Available El estado de Oaxaca representa un importante acervo de maíz en México. Estudios previos han indicado la presencia de muchas variedades locales y razas agronómicas en la Sierra Norte y Valles Centrales. La Sierra Sur ha sido poco estudiada a pesar de la presencia de comunidades indígenas zapotecas, las cuales cultivan maíz, entre otras especies, y han preservado las variedades locales. El presente estudio responde a las siguientes preguntas: ¿cuál es la diversidad de maíz en términos de variedades tradicionales y razas agronómicas en la región zapoteca de Los Loxicha?, ¿la diversidad de maíz sigue un patrón de distribución a lo largo de un gradiente altitudinal?, ¿cuáles prácticas promueven y mantienen esta diversidad? Para contestar estas preguntas se realizó un estudio en cinco municipios de la Sierra Sur de Oaxaca. Durante 2007 se aplicaron entrevistas estructuradas a 930 agricultores para describir el proceso de manejo de semilla. La caracterización morfológica de las razas agronómicas se basó en muestras de mazorcas obtenidas en 375 milpas, con 20 plantas por milpa. Se encontraron altos niveles de diversidad local de maíz, con 36 variedades tradicionales correspondientes a 10 razas agronómicas. Las razas exhibieron diferencias en términos de variación fenotípica, distribución altitudinal y algunas muestran adaptación local. Los agricultores practican algunas formas de manejo ancestral para la selección de mazorcas y semillas, manteniendo, así, ciertos niveles de diferenciación entre las variedades y las razas agronómicas. Sin embargo, al sembrar diferentes variedades dentro de la misma parcela, se promueve el flujo génico y la introgresión entre ellas, manteniendo y promoviendo la diversidad fenotípica y genética.

  20. Tectonic activity revealed by morphostructural analysis: Development of the Sierra de la Candelaria range, northwestern Argentina

    Science.gov (United States)

    Barcelona, H.; Peri, G.; Tobal, J.; Sagripanti, L.; Favetto, A.

    2014-12-01

    The tectonically active broken foreland of NW Argentina is a recent analog of the eastern margin of the Puna plateau during Mio-Pliocene times and likely of other broken forelands worldwide. In order to evaluate active tectonism in the broken foreland of the NW Argentine Andes, we examined the complex geomorphology in the vicinity of the basement-cored Sierra de la Candelaria range at ˜26°S and deciphered multiple episodes of crustal deformation spanning the Pliocene to the Quaternary. Digital elevation models, satellite images and geological data within a GIS environment allowed us to analyze the terrain, drainage networks, river dynamics and structure, as well as to obtain detailed geomorphological mapping, active tectonic indices, longitudinal river profiles and structural sections. Three morphostructural segments were defined based on the structural features, the differential vertical dissection pattern over the basement, the faulted Pliocene to recent deposits, the stepwise propagation of anticlines and the distortion over the fluvial system. By combining the several lines of evidence, we concluded that the Sierra de la Candelaria range was subjected to a multi-stage development. The first stage uplifted the central segment concomitant with the formation of the surrounding ranges and with the main partition phase of the foreland. After a significant time lapse, the mountain range was subjected to southward thick-skinned growth and northward growth via stepwise thin-skinned deformation and exerted control over the dynamics of the Río Rosario. Taking into account the surrounding basins and ranges of the Sierra de la Candelaria, the southern Santa Bárbara System is characterized by partially isolated intramontane basins (Choromoro and Rosario) limited by shielded ranges that caused moisture block and shows continuous deformation. These features were related to early stages of a broken foreland evolution model and modern analogs were found at the northern

  1. Sierra Nevada serpentinites. An important element in the architectonic heritage of Granada (Spain).

    Science.gov (United States)

    Navarro, Rafael; Pereira, Dolores; Rodríguez-Navarro, Carlos; Sebastián-Pardo, Eduardo

    2013-04-01

    Serpentinites are widely used in historic buildings in the whole world, from Ancient Greek or Egypt to more recent colonial buildings in the USA. Serpentinites from Sierra Nevada (S of Spain) have been traditionally used as ornamental elements in historic buildings of Granada city, both indoors and outdoors. The Cathedral, Carlos V Palace, Royal Chancery and some others are good examples of their use. Some other important cases can be found outside Granada, like El Escorial monastery, Las Salesas Reales convent, etc… all of them part of Madrid architectonic heritage. There are two quarries located in Sierra Nevada that supplied all the material to make the different elements in the cited buildings. In this work, a thorough characterization of the main serpentinites from Sierra Nevada, their uses, and their state of conservation in selected buildings from Granada has been performed. Samples from the main original quarry and from one historical building (Real Chancillería) have been analysed, determining the mineralogical and geochemical composition, texture, water parameters (absorption, porosity, density) and possible alteration by salt formation. It has been observed that the mineralogical and geochemical compositions are similar in both sets of samples, although the ones coming from the historical building show a highly advanced state of alteration. Regarding physical and mechanical parameters, samples from the quarry have very low water absorption values, while the porosity of serpentinites sampled from the Real Chancillería is comparatively much higher. We explain this difference as due to the weathering of the emplaced serpentinites by salt crystallization processes (mainly gypsum or epsomite), that generate strong internal pressures causing the disintegration of the whole natural stone. In addition, the increase of the porosity can be caused by dissolution processes related to the presence of acid solutions related to oxidation and hydrolysis of iron

  2. Sierra Nevada

    Directory of Open Access Journals (Sweden)

    Yolanda Jiménez Olivencia

    2006-01-01

    Full Text Available El paisaje, considerado desde la perspectiva sistémica, se concibe como un complejo territorial que puede ser sometido a análisis siguiendo distintas fórmulas de aproximación al mismo. A pesar de las diferencias que se observan entre estos modelos de acercamiento, todos ellos se fundamentan en el análisis integrado de los componentes del paisaje y de sus mutuas relaciones. Las técnicas de integración conducentes a la obtención de unidades sistémicas de paisaje y a la delimitación espacial de las mismas encuentran un aliado excepcional en los SIG. Tanto en el procedimiento de «superposición» como en el de «combinación cartográfica» el empleo de los Sistemas de Información Geográfica representa un avance sustantivo en la instrumentalización del método. En esta comunicación pretendemos concretar el uso de esta herramienta de análisis espacial para cada una de las fases que componen la secuencia metodológica de identificación y cartografía de geosistemas o geocomplejos y, para ello, presentaremos su aplicación a la cuenca vertiente del río Guadix.

  3. Inferring ecological relationships from occupancy patterns for California Black Rails in the Sierra Nevada foothills

    Science.gov (United States)

    Richmond, Orien Manu Wright

    The secretive California Black Rail (Laterallus jamaicensis coturniculus ) has a disjunct and poorly understood distribution. After a new population was discovered in Yuba County in 1994, we conducted call playback surveys from 1994--2006 in the Sierra foothills and Sacramento Valley region to determine the distribution and residency of Black Rails, estimate densities, and obtain estimates of site occupancy and detection probability. We found Black Rails at 164 small, widely scattered marshes distributed along the lower western slopes of the Sierra Nevada foothills, from just northeast of Chico (Butte County) to Rocklin (Placer County). Marshes were surrounded by a matrix of unsuitable habitat, creating a patchy or metapopulation structure. We observed Black Rails nesting and present evidence that they are year-round residents. Assuming perfect detectability we estimated a lower-bound mean Black Rail density of 1.78 rails ha-1, and assuming a detection probability of 0.5 we estimated a mean density of 3.55 rails ha-1. We test if the presence of the larger Virginia Rail (Laterallus limicola) affects probabilities of detection or occupancy of the smaller California Black Rail in small freshwater marshes that range in size from 0.013-13.99 ha. We hypothesized that Black Rail occupancy should be lower in small marshes when Virginia Rails are present than when they are absent, because resources are presumably more limited and interference competition should increase. We found that Black Rail detection probability was unaffected by the detection of Virginia Rails, while, surprisingly, Black and Virginia Rail occupancy were positively associated even in small marshes. The average probability of Black Rail occupancy was higher when Virginia Rails were present (0.74 +/- 0.053) than when they were absent (0.36 +/- 0.069), and for both species occupancy increased with marsh size. We assessed the impact of winter (November-May) cattle grazing on occupancy of California Black

  4. Malaria in British military personnel deployed to Sierra Leone: a case series.

    Science.gov (United States)

    Quantick, Oliver; Howlett-Shipley, R; Roughton, S; Ross, D

    2017-02-01

    From December 2014 to April 2015, seven cases of malaria were seen in 1530 military personnel deployed to Sierra Leone on Operation GRITROCK in response to the West African Ebola outbreak, despite predeployment briefings, prescription of chemoprophylactic agents and bite prevention measures. The cases have prompted discussion regarding the efficacy of current measures and how to prevent future cases in deployed military personnel or more widely, those working in malaria-risk environments. All of the cases have made a full recovery and returned to work. We discuss what can be learnt concerning the choice of chemoprophylactic agent and whether anything further be added to standard operating procedures regarding bite prevention and treatment of cases.

  5. Biodiversity of the Sierra del Divisor Zone Reserved (Peru: a view from small mammals

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    César E. Medina

    2015-10-01

    Full Text Available This study documents the small mammalian diversity in the Zona Reservada Sierra del Divisor (ZRSD. Six sites were evaluated between 2011 and 2013 with capture techniques (Victor snap traps, Tomahawk traps, Pitfall traps and mist nets. 67 species of small mammals were recorded (five marsupials, 10 rodents and 52 bats, 32 of which are new records for the ZRSD and two are species of the most rare and endemic rodents of Peru, the “Peruvian Aquatic Rat” Neusticomys peruviensis (Cricetidae: Ichthyomyini and “Ucayali´s Aquatic Mouse” Amphinectomys savamis (Cricetidae: Oryzomyini. On the other hand, the marsupial Marmosops bishopi; rodents Neacomys minutus, Euryoryzomys macconnelli, Scolomys melanops and Proechimys kulinae; and the bats Artibeus planirostris and Rhinophylla pumilio were the most plenty. Our finding showed the importance of the re-categorization of Reserved Zone to National Park like as a significant contribution to the conservation of the Peruvian mammals.

  6. Comparative Bacteriological Study of Two Wild Boar Populations in Sierra Morena (Ja�n, Spain

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    Antonio NOTARIO

    2010-12-01

    Full Text Available The aim of this study was to investigate the presence of various bacterial species in the wild boar populations of Lugar Nuevo and Selladores-Contadero woodlands from Sierra Morena (Spain. Bacteriological analyses were carried out on a total of 229 wild boar individuals hunted in the period 2000-2003 in eleven experimental plots which are representative for the different biotopes of the area. The following species were detected: Brucella ovis, Clostridium sp., Corynebacterium sp., Streptococcus pneumoniae, Escherichia coli, Mycobacterium bovis, Mycobacterium avium subsp. paratuberculosis, Mannheimia haemolytica, Pasteurella multocida, Pseudomonas aeruginosa, Chlamydophila psittaci, Staphylococcus aureus and Staphylococcus sp. and the bacterial prevalence was estimated for each of them. The results provide useful indications of the health status of wild boar in both locations and highlight the potential of the wild boar populations to act as biological reservoirs of certain microorganisms that can be passed onto other vertebrate wild animals and humans.

  7. Thermal contact algorithms in SIERRA mechanics : mathematical background, numerical verification, and evaluation of performance.

    Energy Technology Data Exchange (ETDEWEB)

    Copps, Kevin D.; Carnes, Brian R.

    2008-04-01

    We examine algorithms for the finite element approximation of thermal contact models. We focus on the implementation of thermal contact algorithms in SIERRA Mechanics. Following the mathematical formulation of models for tied contact and resistance contact, we present three numerical algorithms: (1) the multi-point constraint (MPC) algorithm, (2) a resistance algorithm, and (3) a new generalized algorithm. We compare and contrast both the correctness and performance of the algorithms in three test problems. We tabulate the convergence rates of global norms of the temperature solution on sequentially refined meshes. We present the results of a parameter study of the effect of contact search tolerances. We outline best practices in using the software for predictive simulations, and suggest future improvements to the implementation.

  8. Source identification in acoustics and structural mechanics using Sierra/SD.

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Timothy Francis; Aquino, Wilkins [Duke University Durham, NC; Ross, Michael

    2013-03-01

    In this report we derive both time and frequency-domain methods for inverse identification of sources in elastodynamics and acoustics. The inverse/design problem is cast in a PDE-constrained optimization framework with efficient computation of gradients using the adjoint method. The implementation of source inversion in Sierra/SD is described, and results from both time and frequency domain source inversion are compared to actual experimental data for a weapon store used in captive carry on a military aircraft. The inverse methodology is advantageous in that it provides a method for creating ground based acoustic and vibration tests that can reduce the actual number of flight tests, and thus, saving costs and time for the program.

  9. Lead and cadmium in wild boar (Sus scrofa) in the Sierra Nevada Natural Space (southern Spain).

    Science.gov (United States)

    Mulero, Rocío; Cano-Manuel, Javier; Ráez-Bravo, Arián; Pérez, Jesús M; Espinosa, José; Soriguer, Ramón; Fandos, Paulino; Granados, José E; Romero, Diego

    2016-08-01

    The aims of the present study were to investigate Pb and Cd levels in tissues of wild boar (Sus scrofa) from the Sierra Nevada Natural Space (SNNS) (southern Spain). Heavy metal concentrations in livers, kidneys and bones from 111 animals were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Bones and kidneys were the most Pb- and Cd-contaminated tissues, respectively; Cd concentrations were 5.6 times higher in kidneys than in livers. This is the first biomonitoring study of these pollutants in wild boar tissues in the SNNS, and findings indicate that this population is chronically exposed to these heavy metals. The detected Pb and Cd concentrations were lower than those found in many studies performed in Europe on the same species.

  10. Cacao 3 (Cc 3, Arte rupestre del formativo temprano en Antofagasta de la Sierra, Catamarca, Argentina

    Directory of Open Access Journals (Sweden)

    Alvaro Rodrigo Martel

    2004-01-01

    Full Text Available En el presente trabajo hemos abordado el estudio de la producción del arte rupestre del sitio Cacao 3 –Cc3- (Antofagasta de la Sierra, Catamarca con relación a las prácticas socioculturales de grupos agropastoriles del periodo Formativo Temprano en la Puna meridional argentina, haciendo hincapié en el emplazamiento del sitio y su asociación contextual con las demás evidencias arqueológicas conocidas para el área de estudio y estableciendo las relaciones entre las manifestaciones rupestres de Cc3 con las de otros sitios, a nivel micro y macrorregional, a través de indicadores estilísticos

  11. Mineralización de uranio en la Sierra de Velasco, La Rioja

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    Orquídea Morello

    2013-09-01

    Full Text Available En esta contribución se describe una mineralización de uranio hallada en la sierra de Velasco, provincia de La Rioja, noroeste de Argentina. La geología de la región incluye granitos, pegmatitas y rocas metamórficas. Las rocas hospedantes de la mineralización son el granito La Chinchilla, de edad carbonífera y las metamorfitas del Complejo La Cébila, de edad precámbrica-ordovícica inferior. La mineralización es perigranítica; se encuentra diseminada, en fracturas y alojada en el contacto entre el granito y la metamorfita. En el granito La Chinchilla se identificó un óxido de U-Nb-Ta, y en las metamorfitas se reconocieron silicatos (uranofano, betauranofano, fosfatos (furcalita y meta-autunita y minerales negros de uranio (uraninita -variedad pechblenda- y coffinita.

  12. DIAGNOSIS IMPORTANCE OF RURAL DEVELOPMENT OF A MODEL AGROFORESTAL IN PEASANT COMMUNITIES OF SIERRA DE HUAUTLA

    Directory of Open Access Journals (Sweden)

    Miguel Uribe-Gómez

    2015-07-01

    Full Text Available Family agricultural is socioeconomically important in rural areas, but in Mexico, from the 80's this production system presents social stagnation. This type of agriculture presents a dynamic reality in the interests of each producer and limiting access to factors of production (land, labor and capital. In this investigation a methodology for analysis and diagnosis of production systems in rural areas, in two communities in the Country Sierra de Huautla Tepalcingo, Morelos, Mexico was applied. The proposal is based on an assessment of the environmental, historical, technological and socio-economic assessment of different productive activities for different types of units Family Production of the communities studied. The study showed that 40% of Family Production Units fail to exceed the threshold of survival and show impossibility capitalization medium and long term. So it is advisable to implement a model of local agricultural development to improve the socioeconomic conditions of Family Production Units of peasant communities.

  13. Illegal logging in the Northern Sierra Madre Natural Park, the Philippines

    Directory of Open Access Journals (Sweden)

    Jan van der Ploeg

    2011-01-01

    Full Text Available Illegal logging is a threat to biodiversity and rural livelihoods in the Northern Sierra Madre Natural Park, the largest protected area in the Philippines. Every year between 20,000 and 35,000 cu. m wood is extracted from the park. The forestry service and municipal governments tolerate illegal logging in the protected area; government officials argue that banning an important livelihood activity of households along the forest frontier will aggravate rural poverty. However this reasoning underestimates the scale of timber extraction, and masks resource capture and collusive corruption. Illegal logging in fact forms an obstacle for sustainable rural development in and around the protected area by destroying ecosystems, distorting markets, and subverting the rule of law. Strengthening law enforcement and controlling corruption are prerequisites for sustainable forest management in and around protected areas in insular southeast Asia.

  14. Education Programs in Post-Conflict Environments: a Review from Liberia, Sierra Leone, and South Africa

    Directory of Open Access Journals (Sweden)

    Hernando Barrios-Tao

    2016-12-01

    Full Text Available Education should be considered as one of the mechanisms for governments and nations to succeed in a post-conflict process. The purpose of this Review Article is twofold: to explain the importance of education in a post-conflict setting, and to describe a few strategies that post-conflict societies have implemented. In terms of research design, a multiple case study approach has been implemented. The paper reviews a unique topic with specific reference to education plans implemented in post-conflict societies such as Liberia, Sierra Leone, and South Africa. Each of them has experienced violent conflicts and has used education as a tool to succeed in their post-conflict process. In sum, there are several educational programs that involve children, young people, survivors, parents, teachers, and local communities as well as curriculums focused on teaching of cultural values and technical skills to improve the quality of life in a post-conflict setting.

  15. Trajectories of internalizing problems in war-affected Sierra Leonean youth: examining conflict and postconflict factors.

    Science.gov (United States)

    Betancourt, Theresa S; McBain, Ryan; Newnham, Elizabeth A; Brennan, Robert T

    2013-01-01

    Three waves of data from a prospective longitudinal study in Sierra Leone were used to examine internalizing trajectories in 529 war-affected youth (ages 10-17 at baseline; 25% female). Latent class growth analyses identified 4 trajectories: A large majority of youth maintained lower levels of internalizing problems (41.4%) or significantly improved over time (47.6%) despite very limited access to care, but smaller proportions continued to report severe difficulties 6 years postwar (4.5%) or their symptoms worsened (6.4%). Continued internalizing problems were associated with loss of a caregiver, family abuse and neglect, and community stigma. Despite the comparative resilience of most war-affected youth in the face of extreme adversity, there remains a compelling need for interventions that address family- and community-level stressors.

  16. Zoonotic disease risk and the bushmeat trade: assessing awareness among hunters and traders in Sierra Leone.

    Science.gov (United States)

    Subramanian, Melanie

    2012-12-01

    The bushmeat industry has been a topic of increasing importance among both conservationists and public health officials for its influence on zoonotic disease transmission and animal conservation. While the association between infectious diseases and the bushmeat trade is well established in the research community, risk perception among bushmeat hunters and traders has not been well characterized. I conducted surveys of 123 bushmeat hunters and traders in rural Sierra Leone to investigate hunting practices and awareness of zoonotic disease risk associated with the bushmeat trade. Twenty-four percent of bushmeat hunters and traders reported knowledge of disease transmission from animals to humans. Formal education did not significantly affect awareness of zoonotic disease transmission. Individuals who engaged exclusively in preparation and trading of bushmeat were more likely to accidentally cut themselves compared to those who primarily engaged in bushmeat hunting (P zoonotic pathogens through accidental self-cutting compared to men (P zoonotic disease transmission risk among vulnerable communities.

  17. Justo Sierra como traductor: entre la tradición y la modernidad

    OpenAIRE

    Mora, Pablo

    2012-01-01

    La faceta de Justo Sierra como traductor es una de las menos estudiadas en su obra y merece más atención con motivo de la celebración del Centenario de la Revolución Mexicana y la apertura de la Universidad Nacional en 1910. Se trata de una contribución definitiva para entender su visión moderna como crítico literario y ensayista de la historia de la literatura mexicana, particularmente en el rubro de la poesía. Este artículo destaca su trabajo como traductor de la poesía parnasiana a la luz ...

  18. Collective Sexual Violence in Bosnia and Sierra Leone: A Comparative Case Study Analysis.

    Science.gov (United States)

    Ten Bensel, Tusty; Sample, Lisa L

    2015-10-08

    Social scientists have long studied the patterns, motivations, and recidivism rates of sexual offenders; however, the majority of prior research has examined rape, where victims are assaulted by a single offender in isolated events. Often overlooked are sexually violent assaults committed during armed conflicts, which often exhibit group-level sexual offending. This oversight could be a result of perceived notions that sexual violence during conflict is a rare or regrettable event; however, it has been documented consistently throughout history. The purpose of this study was to improve our understanding of sexual violence during war by comparing and contrasting preconflict characteristics, conflict framing, and justifications for sexual violence in the Bosnian and Sierra Leone armed conflicts. This greater understanding can then be used to identify factors that may contribute to the collectivization of sexual violence during war.

  19. Global health business: the production and performativity of statistics in Sierra Leone and Germany.

    Science.gov (United States)

    Erikson, Susan L

    2012-01-01

    The global push for health statistics and electronic digital health information systems is about more than tracking health incidence and prevalence. It is also experienced on the ground as means to develop and maintain particular norms of health business, knowledge, and decision- and profit-making that are not innocent. Statistics make possible audit and accountability logics that undergird the management of health at a distance and that are increasingly necessary to the business of health. Health statistics are inextricable from their social milieus, yet as business artifacts they operate as if they are freely formed, objectively originated, and accurate. This article explicates health statistics as cultural forms and shows how they have been produced and performed in two very different countries: Sierra Leone and Germany. In both familiar and surprising ways, this article shows how statistics and their pursuit organize and discipline human behavior, constitute subject positions, and reify existing relations of power.

  20. De los complejos naturales a los paisajes: el modelo de Sierra Nevada

    Directory of Open Access Journals (Sweden)

    Yolanda Jiménez

    2000-01-01

    Full Text Available En este artículo se parte de la idea de que para conseguir una identificación y tipificación de los paisajes es necesario conjugar el análisis de las bases ambientales del territorio con el del modelo de organización socioeconómica y cultural del mismo. En relación con ello se propone una secuencia metodológica, aplicada al macizo de Sierra Nevada, que parte de los complejos sistémicos o estructuras naturales, estudia después los distintos modelos de organización socioterritorial e identifica finalmente los diferentes tipos paisajísticos por asociación o disociación de sistemas en función del grado de homogeneidad o heterogeneidad que les imprime el manejo humano

  1. Las lecturas múltiples de una frontera: Huehuetenango y la Sierra de los Cuchumatanes

    Directory of Open Access Journals (Sweden)

    Alejandro Garay Herrera

    2015-02-01

    Full Text Available En este artículo se pretende analizar la región de Huehuetenango en general, y la Sierra de los Cuchumatanes en particular, como una zona de múltiples transformaciones e identidades que se traslapan entre sí a lo largo del tiempo y el espacio. Al realizar diversas lecturas (históricas, culturales, lingüísticas de esta región, se constata que el concepto de frontera se puede aplicar en diferentes formas y momentos a este espacio geográfico, y no solo en referencia a la moderna frontera política que marca los límites entre dos estados soberanos, como son Guatemala y México.

  2. Paleoclimatic Implications of Holocene Plant Remains from the Sierra Bacha, Sonora, Mexico

    Science.gov (United States)

    Van Devender, Thomas R.; Burgess, Tony L.; Piper, Jessie C.; Turner, Raymond M.

    1994-01-01

    A total of 93 plant taxa were identified from 11 packrat ( Neotoma sp.) midden samples from the Sierra Bacha on the coast of the Gulf of California near Puerto Libertad, Sonora, Mexico. Nine indurated samples have radiocarbon dates ranging from 9970 to 320 yr B.P. Sonoran desertscrub was present on rocky slopes throughout the Holocene. Early Holocene assemblages dominated by Fouquieria columnaris (boojum tree) reflect vegetation and climate more like modern Baja California with greater winter rainfall and cooler summers. Middle Holocene vegetation was essentially modern with modest indications of greater monsoonal rainfall even though cold-water upwelling locally inhibits summer precipitation. The results are similar to all previous midden reconstructions of early and middle Holocene climates in the Sonoran Desert, but contradict general atmospheric circulation model simulations.

  3. Cosmogenic helium and volatile-rich fluid in Sierra Leone alluvial diamonds

    Science.gov (United States)

    Mcconville, P.; Reynolds, J. H.

    1989-01-01

    Noble gas measurements were carried out on two identical splits of a finely powdered harshly acid-washed sample derived from fragments of a single alluvial diamond from Sierra Leone, with essentially identical results obtained for both splits. Isotopic ratios for Ar, Kr, and Xe were found to be atmospheric. Their elemental abundances were high relative to published data, owing to the effect of shock implantation in the crushing step, as was verified in a supplementary experiment. No Ne was detected above the blank level. The He-3 was exceptionally abundant, while He-4 was exceptionally depleted, possibly due to the acid wash. The He-3/He-4 ratio was anomalously high at an R/Ra value of 246 + or - 16. The results support the hypothesis that the He-3 excess in diamonds is cosmogenic.

  4. Calibration and field application of a Sierra Model 235 cascade impactor

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, R.H.

    1984-06-01

    A Sierra Model 235 slotted impactor was used to measure the particle size distribution of ore dust in uranium concentrating mills. The impactor was calibrated at a flow rate of 0.21 m/sup 3//min, using solid monodisperse particles of methylene blue and an impaction surface of Whatman number41 filter paper soaked in mineral oil. The reduction from the impactor's design flow rate of 1.13 m/sup 3//min (40 cfm) to 0.21 m/sup 3//min (7.5 cfm), a necessary adjustment because of the anticipated large particle sizes of ore dust, increased the stage cut-off diameters by an average factor of 2.3. Evaluation of field test results revealed that the underestimation of mass median diameters, often caused by the rebound and reentrainment of solid particles from dry impaction surfaces, was virtually eliminated by using the oiled Whatman number41 impaction surface.

  5. Stratified Sampling of Neighborhood Sections for Population Estimation: A Case Study of Bo City, Sierra Leone.

    Science.gov (United States)

    Hillson, Roger; Alejandre, Joel D; Jacobsen, Kathryn H; Ansumana, Rashid; Bockarie, Alfred S; Bangura, Umaru; Lamin, Joseph M; Stenger, David A

    2015-01-01

    There is a need for better estimators of population size in places that have undergone rapid growth and where collection of census data is difficult. We explored simulated estimates of urban population based on survey data from Bo, Sierra Leone, using two approaches: (1) stratified sampling from across 20 neighborhoods and (2) stratified single-stage cluster sampling of only four randomly-sampled neighborhoods. The stratification variables evaluated were (a) occupants per individual residence, (b) occupants per neighborhood, and (c) residential structures per neighborhood. For method (1), stratification variable (a) yielded the most accurate re-estimate of the current total population. Stratification variable (c), which can be estimated from aerial photography and zoning type verification, and variable (b), which could be ascertained by surveying a limited number of households, increased the accuracy of method (2). Small household-level surveys with appropriate sampling methods can yield reasonably accurate estimations of urban populations.

  6. Paleozoic-involving thrust array in the central Sierras Interiores (South Pyrenean Zone, Central Pyrenees): regional implications

    Science.gov (United States)

    Rodriguez, L.; Cuevas, J.; Tubía, J. M.

    2012-04-01

    This work deals with the structural evolution of the Sierras Interiores between the Tena and Aragon valleys. The Sierras Interiores is a WNW-trending mountain range that bounds the South Pyrenean Zone to the north and that is characterized by a thrust-fold system with a strong lithological control that places preferably decollements in Triassic evaporites. In the studied area of the Sierras Interiores Cenomanian limestones cover discordantly the Paleozoic rocks of the Axial Zone because there is a stratigraphic lacuna developed from Triassic to Late Cretaceous times. A simple lithostratigraphy of the study area is made up of Late Cenomanian to Early Campanian limestones with grey colour and massive aspect in landscape (170 m, Lower calcareous section), Campanian to Maastrichtian brown coloured sandstones (400-600 m, Marboré sandstones) and, finally, Paleocene light-coloured massive limestones (130-230 m), that often generate the higher topographic levels of the Sierras Interiores due to their greater resistance to erosion. Above the sedimentary sequence of the Sierras Interiores, the Jaca Basin flysch succession crops out discordantly. Based on a detailed mapping of the studied area of the Sierras Interiores, together with well and structural data of the Jaca Basin (Lanaja, 1987; Rodríguez and Cuevas, 2008) we have constructed a 12 km long NS cross section, approximately parallel to the movement direction deduced for this region (Rodríguez et al., 2011). The main structure is a thrust array made up of at least four Paleozoic-involving thrusts (the deeper thrust system) of similar thickness in a probably piggyback sequence, some of which are blind thrusts that generate fold-propagation-folds in upper levels. The higher thrust of the thrust array crops out duplicating the lower calcareous section all over the Sierras Interiores. The emplacement of the deeper thrust system generated the tightness of previous structures: south directed piggyback duplexes (the upper

  7. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

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    Ramón Silva-Flores

    Full Text Available Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole, 54 species of Quercus (ca. 9-14%, 7 species of Arbutus (ca. 50% and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally

  8. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

    Science.gov (United States)

    Silva-Flores, Ramón; Pérez-Verdín, Gustavo; Wehenkel, Christian

    2014-01-01

    Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole), 54 species of Quercus (ca. 9-14%), 7 species of Arbutus (ca. 50%) and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally higher in cold

  9. La Población en la mitad: reflexiones sobre Bojayá y La Sierra

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    Juan David Mesa

    2015-12-01

    Full Text Available El presente artículo analiza dos procesos recientes en la historia del conflicto armado colombiano- la masacre de Bojayá y la toma por parte de paramilitares a La Sierra (Barrio de la comuna 8 de Medellín – con el fin de mostrar cómo los diversos actores armados implicados configuraron una serie de dinámicas de control poblacional en las dos comunidades. Lo que se sostendrá, es que si bien fueron procesos diferentes, con actores armados diferentes, ambos reflejaron lo que el conflicto en Colombia en sí mismo ha encarnado siempre y que representa un reto para el eventual postconflicto: el que la población, en la confrontación, siempre esté en el medio, literal y discursivamente hablando. Para el caso específico de Bojayá, se tomó como referencia el documental realizado por el Centro Nacional de Memoria Histórica (2010 sobre la masacre allí cometida. En este caso, la reflexión particular de este acontecimiento girará en torno a los procesos de memoria de sus víctimas y a cómo esta masacre reflejó una configuración violenta del Estado. Para el caso específico de La Sierra, se tomó como referencia el documental realizado por Scott Dalton y Margarita Martínez Escallón (2003 sobre la cotidianidad de algunos miembros del Bloque Metro de los paramilitares en la comuna 8 de Medellín. En este caso, la reflexión se basará en un análisis del discurso inmerso en el documental, para mostrar la dinámica necropolítica alrededor del control poblacional.

  10. Cattle grazing and conservation of a meadow-dependent amphibian species in the Sierra Nevada.

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    Leslie M Roche

    Full Text Available World-wide population declines have sharpened concern for amphibian conservation on working landscapes. Across the Sierra Nevada's national forest lands, where almost half of native amphibian species are considered at risk, permitted livestock grazing is a notably controversial agricultural activity. Cattle (Bos taurus grazing is thought to degrade the quality, and thus reduce occupancy, of meadow breeding habitat for amphibian species of concern such as the endemic Yosemite toad (Anaxyrus [ = Bufo] canorus. However, there is currently little quantitative information correlating cattle grazing intensity, meadow breeding habitat quality, and toad use of meadow habitat. We surveyed biotic and abiotic factors influencing cattle utilization and toad occupancy across 24 Sierra Nevada meadows to establish these correlations and inform conservation planning efforts. We utilized both traditional regression models and Bayesian structural equation modeling to investigate potential drivers of meadow habitat use by cattle and Yosemite toads. Cattle use was negatively related to meadow wetness, while toad occupancy was positively related. In mid and late season (mid July-mid September grazing periods, cattle selected for higher forage quality diets associated with vegetation in relatively drier meadows, whereas toads were more prevalent in wetter meadows. Because cattle and toads largely occupied divergent zones along the moisture gradient, the potential for indirect or direct negative effects is likely minimized via a partitioning of the meadow habitat. During the early season, when habitat use overlap was highest, overall low grazing levels resulted in no detectable impacts on toad occupancy. Bayesian structural equation analyses supported the hypothesis that meadow hydrology influenced toad meadow occupancy, while cattle grazing intensity did not. These findings suggest cattle production and amphibian conservation can be compatible goals within this

  11. A quantitative evaluation of the conservation umbrella of spotted owl management areas in the Sierra Nevada.

    Science.gov (United States)

    Burnett, Ryan D; Roberts, L Jay

    2015-01-01

    Whether by design or default, single species management often serves as an umbrella for species with similar habitat requirements. In recent decades the focus of National Forest management in the Sierra Nevada of California has shifted towards increasing closed canopy mature forest conditions through the protection of areas occupied by the California Spotted Owl (Strix occidentalis occidentalis). To evaluate the implications of these habitat changes and the potential umbrella resulting from a system of owl reserves on the broader avian community, we estimated occupancy of birds inside and outside of Spotted Owl Home Range Core Areas in northeastern California. We used point count data in a multi-species hierarchical Bayesian model incorporating the detection history of 81 species over a two-year time period (2005-2006). A small set of vegetation cover and topography covariates were included in the model to account for broad differences in habitat conditions, as well as a term identifying whether or not a site was within a Core Area. Seventeen species had a negative Core Area effect, seven had a positive effect, and the rest were not significant. Estimated species richness was significantly different with 23.1 species per 100 m radius circle outside Core Areas and 21.7 inside Core Areas. The majority of the species negatively associated with Core Areas are tied to early successional and other disturbance-dependent habitats. Conservation and climate vulnerability rankings were mixed. On average we found higher scores (greater risk) for the species positively associated with Core Areas, but a larger number of species with the highest scores were negatively associated with Core Areas. We discuss the implications for managing the Sierra Nevada ecosystem and illustrate the role of monitoring broader suites of species in guiding management of large complex ecosystems.

  12. Petrología del plutón La Florida, sierra de San Luis

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    E. Carol

    2007-09-01

    Full Text Available El plutón La Florida se localiza en la parte central de la Sierra de San Luis y se aloja en metasedimentitas regionales de grado medio pertenecientes al grupo micaesquistos derivadas de subgrauvacas y areniscas. Es de morfología semicircular, ligeramente elongado en dirección oblicua a la foliación regional, la cual acompaña la forma del plutón en el contacto. Su composición es monzogranítica y marcadamente peraluminoso, y está compuesto por cuarzo, microclino, plagioclasa, muscovita, biotita y granate. El estudio detallado ha permitido establecer que el contenido de biotita de los monzogranitos disminuye hacia los bordes del cuerpo en tanto que la muscovita, generalmente porfiroblástica, aumenta, lo cual conduce a variaciones notables del índice de color de las rocas. Además, se registra una abundante pegmatización que forma tanto diques como cuerpos irregulares en el borde del intrusivo y también en las rocas de caja adyacentes al contacto. Esta zonación sería resultado del incremento de fluidos acuosos durante la etapa tardío magmática, que causaron reacciones subsólidas en la mineralogía ortomagmática. El magma está relacionado con el proceso subductivo desarrollado durante la orogenia famatiniana, muestra afinidad con fundidos sin-colisionales y un tren evolutivo compatible con magmas de tipo S. El plutón de La Florida exhibe algunas diferencias geológicas, petrográficas y composionales con otros granitoides sin-cinemáticos de la sierra de San Luis, encontrándose algunas similitudes solamente con rocas del cordón de El Realito.

  13. [Historical presence of invasive fish in the biosphere reserve sierra de Huautla, Mexico].

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    Mejía-Mojica, Humberto; de Rodríguez-Romero, Felipe Jesús; Díaz-Pardo, Edmundo

    2012-06-01

    The effects of invasive species on native ecosystems are varied, and these have been linked to the disappearance or decline of native fauna, changes in community structure, modification of ecosystems and as vectors of new diseases and parasites. Besides, the development of trade in species for ornamental use has contributed significantly to the import and introduction of invasive fish in some important areas for biodiversity conservation in Mexico, but the presence of these species is poorly documented. In this study we analyzed the fish community in the Biosphere Reserve Sierra de Huautla by looking at diversity changes in the last 100 years. For this, we used databases of historical records and recent collections for five sites in the Amacuzac river, along the Biosphere Reserve area. We compared the values of similarity (Jaccard index) between five times series (1898-1901, 1945-1953, 1971-1980, 1994-1995 and 2008-2009), and we obtained values of similarity (Bray-Curtis) between the five sites analyzed. In our results we recognized a total of 19 species for the area, nine non-native and ten native, three of which were eliminated for the area. Similarity values between the early days and current records were very low (.27); the major changes in the composition of the fauna occurred in the past 20 years. The values of abundance, diversity and similarity among the sampling sites, indicate the dominance of non-native species. We discuss the role of the ornamental fish trade in the region as the leading cause of invasive introduction in the ecosystem and the possible negative effects that at least four non-native species have had on native fauna and the ecosystem (Oreochromis mossambicus, Amatitlania nigrofasciata, Pterygoplichthys disjunctivus and P pardalis). There is an urgent need of programs for registration, control and eradication of invasive species in the Sierra de Huautla Biosphere Reserve and biodiversity protection areas in Mexico.

  14. Partitioning of water flux in a Sierra Nevada ponderosa pine plantation

    Science.gov (United States)

    Kurpius, M.R.; Panek, J.A.; Nikolov, N.T.; McKay, M.; Goldstein, Allen H.

    2003-01-01

    The weather patterns of the west side of the Sierra Nevada Mountains (cold, wet winters and hot, dry summers) strongly influence how water is partitioned between transpiration and evaporation and result in a specific strategy of water use by ponderosa pine trees (Pinus ponderosa) in this region. To investigate how year-round water fluxes were partitioned in a young ponderosa pine ecosystem in the Sierra Nevada Mountains, water fluxes were continually measured from June 2000 to May 2001 using a combination of sap flow and eddy covariance techniques (above- and below-canopy). Water fluxes were modeled at our study site using a biophysical model, FORFLUX. During summer and fall water fluxes were equally partitioned between transpiration and soil evaporation while transpiration dominated the water fluxes in winter and spring. The trees had high rates of canopy conductance and transpiration in the early morning and mid-late afternoon and a mid-day depression during the dry season. We used a diurnal centroid analysis to show that the timing of high canopy conductance and transpiration relative to high vapor pressure deficit (D) shifted with soil moisture: during periods of low soil moisture canopy conductance and transpiration peaked early in the day when D was low. Conversely, during periods of high soil moisture canopy conductance and transpiration peaked at the same time or later in the day than D. Our observations suggest a general strategy by the pine trees in which they maximize stomatal conductance, and therefore carbon fixation, throughout the day on warm sunny days with high soil moisture (i.e. warm periods in winter and late spring) and maximize stomatal conductance and carbon fixation in the morning through the dry periods. FORFLUX model estimates of evaporation and transpiration were close to measured/calculated values during the dry period, including the drought, but underestimated transpiration and overestimated evaporation during the wet period. ?? 2003

  15. Pattern of skin infections in black Africans of Sierra Leone (West Africa

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    Bari Arfan ul

    2007-01-01

    Full Text Available Background: Physical differences among human populations may lead to variable prevalence of skin disorders in different ethnicities. Skin infections are one of the important curable and largely preventable categories of skin disorders in the communities. Aim: The purpose of the study was to see the patterns of skin infections in black Africans of Sierra Leone and to compare with other ethnic populations. Materials and Methods: Local blacks of all age groups presenting in Dermatology out patient department of Pak Field Hospital (established as a part of UN peacekeeping mission in Sierra Leone were included (from Nov 2004 to Oct 2005. Relevant clinical history and physical examination was done. Laboratory investigations were carried out when indicated. Skin diseases were broadly classified into two major categories i.e., infective and noninfective. Among infective, sexually transmitted infections were again separated. Nonblack settlers in the area and UN troops were not included in the study. Data was recorded and analyzed by Microsoft Excel program. Results: 3011 patients belonging to different local tribes having a variety of skin disorders were seen. Patients were of all ages and both sexes ranging from one month to 73 years of age. The Infective skin disorders were seen in 61.7% patients and most prevalent were superficial fungal infections (41.2% followed by, sexually transmitted infections (9.9% and parasitic infections (6.5%. Bacterial and viral infections were rare and so was the scabies. More than 90% parasitic infections were onchocerciasis with full spectrum of cutaneous manifestations. Conclusion: Pattern of skin infections in blacks varies considerably from other ethnic races. Environmental factors, geographical location and free existence of vector for onchocerciasis in West African region, possibly have a significant influence in this variable prevalence.

  16. High temperatures and inverted metamorphism in the schist of Sierra de Salinas, California

    Science.gov (United States)

    Kidder, Steven; Ducea, Mihai N.

    2006-01-01

    New field and thermobarometric work in the Californian Salinian block clarifies current and pre-Tertiary relationships between the schist of Sierra de Salinas and Cretaceous arc-related granitic rocks. The contact is variably preserved as a brittle fault and high-temperature mylonite zone, the Salinas shear zone, which represents the contact between North America and sediments accreted above the Farallon slab between ˜ 76 Ma and ˜ 70 Ma. Near granulite facies, prograde replacement of hornblende with clinopyroxene is associated with deformation of plutonic rocks at the base of the upper plate. In the lower plate, the schist of Sierra de Salinas, garnet-biotite thermometry indicates decreasing temperatures down-section from at least 714 °C to ˜ 575 °C over an exposed thickness of ˜ 2.5 km, consistent with petrologic evidence of an inverted metamorphic gradient. The measured temperatures are significantly higher than observed at shallow levels above subducting slabs or predicted by 2D computational models assuming low shear stresses. Previous workers have called upon shear heating to explain similar observations in the correlative Pelona schist, an unlikely scenario given the results of recent rock deformation experiments which predict that feldspar-quartz-mica aggregates are far too weak to withstand stresses of ˜ 70 MPa required by the shear heating hypothesis. As an alternative, we propose that high temperatures resulted from conductive heating while the leading edge of the schist traveled ˜ 150 km beneath the recently active Salinian continental arc during the initiation of shallow subduction. Weakening of the schist due to high temperatures helped facilitate the collapse of the Salinian arc as the schist was emplaced. Schist emplacement coincided with loss of lower, mafic portions of the arc, and therefore evolution of the Southern California crust towards a more felsic composition.

  17. The mineral resources of the Sierra Nevada de Santa Marta, Columbia (Zone I)

    Science.gov (United States)

    Tschanz, Charles McFarland; Jimeno V., Andres; Cruz, Jaime B.

    1970-01-01

    The Sierra Nevada de Santa Maria on the north coast of Colombia is an isolated triangular mountain area that reaches altitudes of almost 19,000 feet. The exceedingly complex geology is shown on the 1:200,000 geologic map. Despite five major periods of granitic intrusion, three major periods of metamorphism, and extensive volcanic eruptions, metallic deposits are small and widely scattered. Sulfide deposits of significant economic value appear to be absent. Many small copper deposits, of chalcocite, cuprite, malachite, and azurite are found in epidotized rock in Mesozoic redbeds and intercalated volcanic rocks, but their economic potential is very small. Deposits of other common base metals appear to be absent. The most important metallic deposits may prove to be unusual bimineralic apatite-ilmenite deposits associated with gneissic anorthosite. The known magnetite deposits are too small to be exploited commercially. Primary gold deposits have not been identified and the placer deposits are uneconomic and very small. The largest and most important deposits are nonmetallic. Enormous reserves of limestone are suitable for cement manufacture and some high-purity limestone is suitable for the most exacting chemical uses. Small deposits of talc-tremolite could be exploited locally for ceramic use. The important noncoking bituminous coal deposits in the Cerrej6n area are excluded from this study. Other nonmetallic resources include igneous dimension stone in a variety of colors and textures, and agricultural dolomite. There probably are important undeveloped ground water resources on the slopes of the wide Rancheria and Cesar valleys, which separate the Sierra Nevada from the Serrania de Persia.

  18. Nuevo Rowlandius Reddell & Cokendolpher, 1995 (Schizomida: Hubbardiidae de la Sierra San Luis, Venezuela noroccidental

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    Luis F. de Armas

    2009-01-01

    Full Text Available Se describe un nuevo esquizómido del género Rowlandius Reddell & Cokendolpher, 1995, proveniente de la Sierra de San Luis, Estado Falcón, en Venezuela noroccidental. Rowlandius arduus sp. n. se caracteriza por el dedo móvil del quelícero con un diminuto diente subdistal, una débil eminencia dorsoposterior en el segmento abdominal XII del macho y espermatecas constituidas por dos pares de lóbulos largos y sinuosos, tenuemente quitinizados, sin bulbo terminal notable. Su asignación al género Rowlandius es tentativa, pues posee varios caracteres que no concuerdan plenamente con el mismo, sin embargo la carencia de caracteres sinapomórficos limita su asignación a otro género. Este es el primer registro del género para Venezuela y la tercera especie suramericana conocida.A new species of the genus Rowlandius Reddell & Cokendolpher, 1995 is described from Sierra San Luis, Falcón State, northwestern Venezuela. Rowlandius arduus sp. n. may be characterized by having movable finger of chelicerae with a diminute sub-distal tooth, male with a poorly developed dorsal eminence on abdominal segment XII, and female with two pairs of weakly sclerotized, sinuous spermathecal lobes, without conspicuous terminal lobe. It is assigned to Rowlandius tentatively, because some characters are not congruent with this genus, nevertheless the absence of synapomorphic characters limits its inclusion in other one. This is the first record of the genus from Venezuela, and the third South American species described.

  19. NOAA TIFF Image - 1 m Backscatter Mosaic of Abrir La Sierra Bank, PR (2007) collected using a SeaBat Reson 8124 (200 kHz) multibeam echosounder

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    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the Abrir La Sierra Bank off the coast of western Puerto Rico, collected using a SeaBat Reson 8124...

  20. NOAA ESRI Geotiff - 10m Bathymetry around Abrir La Sierra Bank, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Geotiff with 10 meter cell size representing the bathymetry of selected portions of seafloor around Abrir La Sierra Bank in Puerto...

  1. Análisis comparativo de la composición de tres comunidades de Squamata de la Sierra Grande de Córdoba, Argentina

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    Martori, Ricardo

    1994-01-01

    Full Text Available The differences and similarities of lizard assemblages can be explaned by historical or ecological factors or by the interaction of both. To examine these hypothesis we selected three communities with similar environmental influences in the Sierra Grande de Córdoba (Argentina. The sites selected where: Villa Las Rosas (31°56', 65°03', dep. San Javier on the west side of the Sierra, Tanti (310,22, 64°36' dep. Punilla on the east side of the Sierra and Achiras (33°10', 64°59' dep. Rio Cuarto on the southem extreme of the Sierra. All these sites have more than eight species of lizards. The diversity of each site is described and the novelties, sustitutions and absences for each locality are discussed and compared with three external communities. A phylogenetic hypothesis of the species involved in this study is need to resolve the biogeographic problems.

  2. Mortality factors for dead trees from a subset of plots from the Sierra Nevada Forest Dynamics Plot Network from 1998 to 2010

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    U.S. Geological Survey, Department of the Interior — This dataset was used to summarize and analyze the mortality factors recorderd on dead trees in the Sierra Nevada Forest Dynamics Plot Network, which is managed by...

  3. NOAA TIFF Image - 1 m Backscatter Mosaic of Abrir La Sierra Bank, PR (2007) collected using a Kongsberg EM 1002 (95 kHz) multibeam echosounder

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the Abrir La Sierra Bank off the coast of western Puerto Rico, collected using a Kongsberg EM 1002...

  4. The post-Laramide clastic deposits of the Sierra de Guanajuato: Compositional implications on the tectono-sedimentary and paleographic evolution

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    R. Miranda-Avilés

    2016-11-01

    Full Text Available This article presents the results of the study on sedimentation, sedimentary environments, tectono-sedimentary and paleogeographic evolution of post-Laramide clastic deposits and pre-volcanism of the Sierra Madre Occidental in the Sierra de Guanajuato, central Mexico. The Eocene Duarte Conglomerate and Guanajuato Conglomerate were deposited in the middle and distal parts of alluvial fans. The studied rocks are composed of limestone clasts, granite, andesite, metasediments, diorite, and pyroxenite, indicating the erosion of uplifted blocks of the basal complex of the Sierra de Guanajuato (Arperos basin. The petrographic and compositional analysis of limestone shows a textural variation from basin limestones and shallow platform limestones. The shallow platform limestone contain bivalves, brachiopods, gastropods, echinoderms and benthic foraminifera from the Berriasian-Valanginian. The shallow-water limestone corresponds to the boundary of the Arperos basin whose original outcrops currently not outcrop in the Sierra de Guanajuato.

  5. NOAA ESRI Grid - 3m Bathymetry around Abrir La Sierra Bank, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Grid with 3 meter cell size representing the bathymetry of selected portions of seafloor around Abrir La Sierra Bank in Puerto Rico,...

  6. NOAA ESRI Geotiff - 3m Bathymetry around Abrir La Sierra Bank, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Geotiff with 3 meter cell size representing the bathymetry of selected portions of seafloor around Abrir La Sierra Bank in Puerto Rico,...

  7. Effects of Climate and Fuels Management on Wildfire Occurrence, Size, Severity and Emissions in the Sierra Nevada

    Science.gov (United States)

    Westerling, A. L.; Fites, J. A.; Keyser, A.

    2015-12-01

    Annual wildfire burned area in federally managed Sierra Nevada forests has increased by more than 10,000 ha per decade since the early 1970s. At the same time, recent years have seen some extremely large fires compared to the historical record, with significant areas of moderate to high severity fire (e.g., McNally 2002, Rim 2013, King 2014 fires). Changes to fuels and fire regimes due to fire suppression and land use, as well as warming temperatures and the occurrence of drought, are thought to be significant factors contributing to increased risks of large, severe fires in Sierra Nevada forests. Over 70% of the vegetated area in federally managed forests in the Sierra Nevada is classified as having altered fuels and fire regimes, while average annual temperature in the Sierra Nevada has been above the long term mean for all but four years in the past two decades. As climate is expected to continue warming for decades to come, we explored fuels management scenarios as the primary tools available to modify risks of large, severe wildfires. We developed experimental statistical models of fire occurrence, fire size, and high severity burned area, to explore the interaction between climate and altered fuels conditions. These models were applied to historical climate conditions, a sample of future climate projections, and to both current fuels conditions and a range of scenarios for fuels treatments. Emissions from wildfires were estimated using the Fire Inventory from the National Center for Atmospheric Research. Our models project that average annual burned area in the Sierra Nevada will more than double by mid-century. Similarly, particulate and other pollution emissions from Sierra Nevada wildfires are projected to more than double, even if future fire severity does not change. Fuels treatment scenarios significantly reduced simulated future burned area and emissions below untreated projections. High severity burned area responded to both climate and fuels

  8. Transient thermal regimes in the Sierra Nevada and Baja California extinct outer arcs following the cessation of Farallon subduction

    Science.gov (United States)

    Erkan, Kamil; Blackwell, David

    2009-02-01

    We examine the thermal relaxation of the Sierra Nevada and Baja California extinct outer arc blocks following the progressive cessation of Farallon subduction under western North America beginning at ˜30 Ma. Being parts of the same outer arc until the inland jump of the San Andreas transform fault at ˜5 Ma, these two regions show many similarities in their geology, geomorphology, rigid body behavior, and their relatively low seismicity. In the thermal model, we combine results of different geophysical and geophysical studies to constrain the thermal state and geometry of the outer arcs before the cessation of subduction and then model the postsubduction temperature responses in these regions using the results of the tectonic reconstructions. A well-constrained regional thermal model of these blocks using the results of many earlier studies in these regions confirms that the present low heat flow values in these regions are the remnants of the very cold outer arc thermal regime of the subduction zone even as long as 30 Ma after cessation of subduction. Thus the entire Pacific boundary of the North American plate is still in a transient thermal state. The calculated low lithospheric temperatures in the Sierra Nevada and Peninsular blocks correlate very well with their rigid body behavior obtained from geodetic studies, and seismogenic layer thicknesses obtained from seismological studies. This is in contrast with the fact that both regions are surrounded by intense deformation associated with the western North America intraplate and extraplate motions. These low-temperature islands play important roles in the present interaction of the North American and Pacific plates and contribute to the broad deformation of the transform boundary. The thermal relaxation of the extinct outer arcs includes both vertical heating from the underlying asthenosphere and the lateral heating from the extinct back arc (Basin and Range), which has remained as a high heat flow region after

  9. Estructura de los encinares de la sierra de Santa Rosa, Guanajuato, México Oak forest structure in the Sierra de Santa Rosa range, Guanajuato, Mexico

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    Juan Martínez-Cruz

    2009-04-01

    Full Text Available Se describe la estructura de 4 asociaciones de encinares en el oriente de la sierra de Santa Rosa, Guanajuato, con el método de cuadrantes al punto central (21 transectos, donde se contabilizaron 2 320 individuos arbóreos y arbustivos, que incluyen 36 especies, 22 géneros y 15 familias. La asociación Quercus potosina-Q. castanea (QPC registró la mayor riqueza (29 especies y el menor número de individuos por ha-1 (650. Por el contrario, la asociación de Q. laurina-Q. rugosa (QLR presentó sólo 12 especies, pero la mayor densidad de arbustos por ha-1 (5 593. El índice α de Fisher y el análisis de rarefacción ratificaron que la asociación de QPC es la más diversa. La asociación Q. potosina-Q. eduardii (QPE fue la de mayor equidad. Los índices de Simpson (cualitativo y de Sørensen (cuantitativo coincidieron en que las asociaciones Q. coccolobifolia-QLR y QLR-QPE presentan la mayor diversidad beta. Debido al marcado deterioro que se observa en estos bosques, la heterogeneidad de las asociaciones de encinares respecto a su composición, atributos de estructura y diversidad, deben considerarse en acciones futuras encaminadas a lograr un manejo más sustentable de los recursos naturales que albergan estos bosques, así como acciones particulares de conservación y restauración.The structure of 4 oak associations in the western part of the Sierra de Santa Rosa range in Guanajuato state is described. Oak associations were sampled using the point centered quarter method (21 sites. We censused 2 320 individuals of trees and shrubs belonging to 36 species, in 22 genera and 15 families. Observed species richness (29 was highest in the Quercus potosina-Q. castanea association (QPC but tree density was the lowest (650 individuals/ha. Meanwhile, the Q. laurina-Q. rugosa association (QLR had the least number of observed species (12, but the maximum shrub density (5 593 individual/ ha. The Fisher index for alpha diversity and the rarefaction

  10. Plutón La Costa, una expresión de magmatismo tipo-s en el sector noreste de la Sierra de Velasco, Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    P.H. Alasino

    2006-06-01

    Full Text Available Estudios combinados de petrología, química mineral y geoquímcia de roca total revelan la presencia de dos unidades graníticas peraluminosas con minerales aluminosos magmáticos tales como granate y mica blanca y la presencia distintiva de turmalina. Las evidencias aquí presentadas indican que estas dos facies, Anillaco y Anjullón, junto a la unidad peraluminosa Santa Cruz estudiada en trabajos previos, constituyen una serie de rocas co-sanguíneas, emplazadas en niveles someros de la corteza y las cuales conforman una unidad ígnea mayor denominada aquí plutón La Costa, la cual aflora en el sector noreste de la sierra de Velasco. La asociación mineral, la química mineral y la geoquímica de roca total permiten definir al plutón La Costa como un clásico granitoide tipo-S, derivado de una roca fuente de composición esencialmente pelítica. Diferentes estudios demuestran que la generación de granitoides tipo-S requiere de un alto gradiente geotérmico, por lo cual el plutón La Costa indica que la corteza en esta región soportó un notable calentamiento durante la generación del magma. Sin embargo, la ausencia de datos geocronológicos impide definir el evento tectomagmático que produjo el magma primordial de este plutón.

  11. Using Power-Sharing to Win a War: The Implementation of the Lomé Agreement in Sierra Leone Wie man Machtteilung benutzt, um einen Krieg zu gewinnen: Die Umsetzung des Lomé-Abkommens in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Helga Malmin Binningsbø

    2009-01-01

    Full Text Available To end the civil war in Sierra Leone the government and the Revolutionary United Front (RUF signed a peace agreement guaranteeing power-sharing in July 1999. Such power-sharing is a widely used, often recommended political arrangement to overcome deep divisions between groups. However, scholars disagree on whether power-sharing causes peace, or, on the contrary, causes continuing violence. One reason for this is the literature’s tendency to neglect how power-sharing is actually put into place. But post-agreement implementation is essential if we are to judge the performance of power-sharing. Therefore, we investigate the role played by power-sharing in terminating the civil war in Sierra Leone. We argue that the government was able to use the peace agreement to pursue its goal of ending the war through marginalising the RUF. Zur Beendigung des Bürgerkriegs in Sierra Leone unterzeichneten die Regierung und die Revolutionary United Front (RUF im Juli 1999 eine Friedensvereinbarung, die Machtteilung garantierte. Machtteilung ist ein verbreitet eingesetztes und häufig empfohlenes politisches Konzept, um die tiefe Spaltung zwischen Konfliktgegnern zu überwinden. In der akademischen Debatte gibt es allerdings keine Übereinstimmung dahingehend, ob Machtteilung zum Frieden führt oder, im Gegenteil, zu einer Fortsetzung der Gewalt. Ein Grund dafür liegt darin, dass die Frage nach der realen Umsetzung von Machtteilungsklauseln in der Literatur tendenziell vernachlässigt wird. Die Bewährung in der Umsetzung ist allerdings ganz wesentlich für die Beurteilung der Stärken des Konzepts. Im vorliegenden Beitrag wird daher die Rolle analysiert, die Machtteilung bei der Beendigung des Krieges in Sierra Leone gespielt hat. Die Autorinnen argumentieren, dass die Regierung die Friedensvereinbarung dazu nutzen konnte, ihr Ziel der Marginalisierung der RUF zu erreichen.

  12. Manifestaciones geomorfológicas y geofísicas de una estructura geológica profunda al sur de la Sierra de Pie de Palo, Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    M. Patricia Martínez

    2008-06-01

    Full Text Available En el presente trabajo se vinculan las evidencias geomorfológicas y geofísicas con la existencia de una estructura emplazada en la corteza superior, ubicada al sur de la sierra de Pie de Palo y con similares dimensiones que ésta. A partir de valores de gravedad, se calculó una carta de anomalías de Bouguer, correspondiente a la sierra de Pie de Palo y zonas aledañas. Se aplicó el método de deconvolución de Euler, variando adecuadamente el ancho de ventana entre 20 y 35 km y con dos índices estructurales: 0,5 y 1. Las respuestas obtenidas con este método señalan en ambos casos una concentración de soluciones que se corresponden con rasgos estructurales reconocidos geológicamente como: la megafalla Desaguadero Bermejo; el borde oriental de la Precordillera; la megafractura de El Molle. Por otro lado, existe una gran acumulación de soluciones de forma trapezoidal al sur de la sierra de Pie de Palo. Estas fuentes responden a profundidades en su mayoría ubicadas entre 10 y 20 kilómetros, indicando una cuarta estructura profunda o alto de basamento. Las evidencias geomorfológicas encontradas en la región corroborarían la existencia de esta estructura en ascenso, sugerida por las sucesivas migraciones de los cauces de los ríos San Juan hacia el norte y Mendoza y Tunuyán hacia el sur, tanto en épocas prehistóricas como históricas. Este fenómeno podría compararse con el ocurrido durante el terremoto de 1977, con epicentro en la provincia de San Juan, el cual produjo un ascenso de la sierra de Pie de Palo de 1,20 metros.

  13. Effect of previous chilling storage on quality loss in frozen (–20 °C sierra (Scomberomorus sierra muscle packed with a low-density polyethylene film containing butylated hydroxytoluene

    Directory of Open Access Journals (Sweden)

    Herlinda Soto-Valdez

    2015-03-01

    Full Text Available Rancidity development during frozen storage (–20 °C of sierra fish (Scomberomorus sierra was studied. Fillets were packed in low-density polyethylene films with and without butylated hydroxytoluene added (BHT-LDPE and LDPE respectively. Fillets stored with no package were used as control. Special attention was given to the effect of previous ice storage (0, 3, 6, 9 and 15 days on the quality of the frozen fish. Physical (pH and texture and chemical (peroxide value, PV and thiobarbituric acid index, TBA-i analyses were carried out. Lipid oxidation increased with ice storage time in fish muscle without film packing, being greater than the film packed muscle (with and without antioxidant. An effect of previous ice storage time was observed on the frozen product (in all treatments. However, fish muscle with film packing containing antioxidant showed less lipid deterioration. Under the conditions applied in this study, the plastic films with antioxidant prevented the lipids oxidation during the cold handling of the sierra muscle.

  14. Human-induced uplift of the Sierra Nevada Mountains and seismicity modulation on the San Andreas Fault

    Science.gov (United States)

    Amos, Colin; Audet, Pascal; Hammond, William C.; Burgmann, Roland; Johanson, Ingrid A.; Blewitt, Geoffrey

    2014-05-01

    We investigate the cause of geodetically observed mountain uplift in the Sierra Nevada, western US. In the process, we reveal a possible human-induced mechanism that may be driving Sierra Nevada uplift, and may also be pushing the San Andreas Fault closer to failure. An initial study of the Sierra Nevada [Hammond et al., Geology, 40, 2012] exploited the complementary strengths of point positions from GPS and blanket coverage measurements from InSAR, to show that contemporary vertical motion of the Sierra Nevada is between 1 - 2 mm/yr relative to the comparatively stable Great Basin to the east. One possible interpretation of this is that the most modern episode of tectonic uplift is still active in the Sierra Nevada. However, we now discover that GPS stations surrounding the southern San Joaquin Valley in California show a pattern of uplift concentrated not only in the Sierra Nevada to the east, but more broadly along the basin margins, including the adjacent central Coast Range to the west. Peak vertical velocities reach values up to 1 - 3 mm/yr. This suggests the San Joaquin Valley plays a key role in the uplift of the Sierra Nevada to the east, with possible implications for the San Andreas Fault to the west. Anthropogenic groundwater depletion in the southern San Joaquin Valley has been massive and sustained, therefore hydrological loading variation might explain contemporary uplift. To test this, we apply a simple elastic model that uses a line load centered along the valley axis, a range of elastic parameters, and published estimates of the integrated rate of mass loss due to groundwater removal over the last decade. Predicted uplift centered along the valley axis matches well with patterns of GPS motion, with the upward vertical rates decaying away from the valley margins. Observed seasonal variability in the vertical GPS positions lends support for this model, showing peak uplift for stations surrounding the valley during the dry summer and fall months. On

  15. Search for an annual modulation of dark-matter signals with a germanium spectrometer at the Sierra Grande Laboratory

    CERN Document Server

    Abriola, D; Brodzinski, R L; Collar, J I; Gregorio, D E D; Farach, H A; García, E; Gattone, A O; Guérard, C K; Hasenbalg, F; Huck, H; Miley, H S; Morales, A; Morales, J; De Solorzano, A O; Puimedón, J; Reeves, J H; Salinas, A; Sarsa, M L; Villar, J A

    1999-01-01

    Data collected during three years with a germanium spectrometer at the Sierra Grande underground laboratory have been analyzed for distinctive features of annual modulation of the signal induced by WIMP dark matter candidates. The main motivation for this analysis was the recent suggestion by the DAMA/NaI Collaboration that a yearly modulation signal could not be rejected at the 90% confidence level when analyzing data obtained with a high-mass low-background scintillator detector. We performed two different analyses of the data: First, the statistical distribution of modulation-significance variables (expected from an experiment running under the conditions of Sierra Grande) was compared with the same variables obtained from the data. Second, the data were analyzed in energy bins as an independent check of the first result and to allow for the possibility of a crossover in the expected signal. In both cases no statistically significant deviation from the null result was found, which could support the hypothe...

  16. Deposition patterns and transport mechanisms for the endocrine disruptor 4-nonylphenol across the Sierra Nevada Mountains, California.

    Science.gov (United States)

    Lyons, Rebecca; Van de Bittner, Kyle; Morgan-Jones, Sean

    2014-12-01

    Dust and particulate distribution patterns are shifting as global climate change brings about longer drought periods. Particulates act as vehicles for long range transport of organic pollutants, depositing at locations far from their source. Nonylphenol, a biodegradation product of nonylphenol polyethoxylate, is a known endocrine disruptor. Nonylphenol polyethoxylate enters the environment as an inert ingredient in pesticide sprays, potentially traveling great distances from its application site. This is of concern when a highly agricultural region, California's Central Valley, lies adjacent to sensitive areas like the Eastern Sierra Nevada Mountains. The distribution and transport mechanisms for 4-nonylphenol were investigated in Eastern Sierra Nevada canyons. Regions close to canyon headwalls showed trace amounts of 4-nonylphenol in surface water, snow, and atmospheric deposition. Exposed areas had yearly average concentrations as high as 9 μg/L. Distribution patterns are consistent with particulate-bound transport. This suggests with increasing drought periods, higher levels of persistent organic pollutants are likely.

  17. 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.

  18. Hydrological conditions and evaluation of sustainable groundwater use in the Sierra Vista Subwatershed, Upper San Pedro Basin, southeastern Arizona

    Science.gov (United States)

    Gungle, Bruce; Callegary, James B.; Paretti, Nicholas V.; Kennedy, Jeffrey R.; Eastoe, Christopher J.; Turner, Dale S.; Dickinson, Jesse E.; Levick, Lainie R.; Sugg, Zachary P.

    2016-08-18

    This study assessed progress toward achieving sustainable groundwater use in the Sierra Vista Subwatershed of the Upper San Pedro Basin, Arizona, through evaluation of 14 indicators of sustainable use. Sustainable use of groundwater in the Sierra Vista Subwatershed requires, at a minimum, a stable rate of groundwater discharge to, and thus base flow in, the San Pedro River. Many of the 14 indicators are therefore related to long-term or short-term effects on base flow and provide us with a means to evaluate groundwater discharge to and base flow in the San Pedro River. The indicators were based primarily on 10 to 20 years of data monitoring in the subwatershed, ending in 2012, and included subwatershedwide indicators, riparian-system indicators, San Pedro River indicators, and springs indicators.

  19. Petrographic (thin section) notes on selected samples from hornblende-rich metamorphic terranes in the southernmost Sierra Nevada, California

    Science.gov (United States)

    Ross, Donald Clarence

    1983-01-01

    Medium- to high-grade metamorphic rocks that are commonly hornblende-rich, and probably largely of 'oceanic' affinity, are widespread in the southernmost Sierra Nevada, California. These metamorphic rocks are largely amphibolite, mafic and felsic gneiss, granofels, and hypersthene granulite The mineral assemblages suggest that these rocks are at least in part of granulite grade, represent relatively deep crustal levels, and may be exposed parts of the root zone of the Sierra Nevada batholith. Access to the largest area of these rocks is relatively limited and for this reason petrographic data (textures and mineral content based on thin section study) are summarized here. Directions to readily accessible localities are presented, however, where the major metamorphic rock types can be examined and sampled.

  20. Medicinal plants used in a Totonac community of the Sierra Norte de Puebla: Tuzamapan de Galeana, Puebla, Mexico.

    Science.gov (United States)

    Martinez Alfaro, M A

    1984-07-01

    Totonac Indians, like other aboriginal peoples, use many plants, animals and minerals in treating illness. We collected our information among mountain dwelling Totonacs (totonacos de la Sierra). These Totonacs from the mountain areas are only beginning to be studied from an ethnobotanical viewpoint. Here we report on their herbal remedies and briefly discuss their traditional medicine. Finally, the role of Western medicine in Totonac life is analyzed.

  1. Remote Sensing Analysis of the Sierra Blanca (Faskin Ranch) Low-Level Radioactive Waste Disposal Site, Hudspeth County, Texas

    Energy Technology Data Exchange (ETDEWEB)

    LeMone, D. V.; Dodge, R.; Xie, H.; Langford, R. P.; Keller, G. R.

    2002-02-26

    Remote sensing images provide useful physical information, revealing such features as geological structure, vegetation, drainage patterns, and variations in consolidated and unconsolidated lithologies. That technology has been applied to the failed Sierra Blanca (Faskin Ranch) shallow burial low-level radioactive waste disposal site selected by the Texas Low-Level Radioactive Waste Disposal Authority. It has been re-examined using data from LANDSAT satellite series. The comparison of the earlier LANDSAT V (5/20/86) (30-m resolution) with the later new, higher resolution ETM imagery (10/23/99) LANDSAT VII data (15-m resolution) clearly shows the superiority of the LANDSAT VII data. The search for surficial indications of evidence of fatal flaws at the Sierra Blanca site utilizing was not successful, as it had been in the case of the earlier remote sensing analysis of the failed Fort Hancock site utilizing LANDSAT V data. The authors conclude that the tectonic activity at the Sierra Blanca site is much less recent and active than in the previously studied Fort Hancock site. The Sierra Blanca site failed primarily on the further needed documentation concerning a subsurface fault underneath the site and environmental justice issues. The presence of this fault was not revealed using the newer LANDSAT VII data. Despite this fact, it must be remembered that remote sensing provides baseline documentation for determining future physical and financial remediation responsibilities. On the basis of the two sites examined by LANDSAT remote sensing imaging, it is concluded that it is an essential, cost-effective tool that should be utilized not only in site examination but also in all nuclear-related facilities.

  2. Paysage en ruine et voyage au service du fantastique: à propos d’ Inès de las Sierras

    OpenAIRE

    Pedro Méndez; Concepción Palacios

    2014-01-01

    Charles Nodier’s Inés de las Sierras, a story set in Spain, features two elements which represent key components of the fictional world of the author and which are often concurrent in nineteenth-century prose, namely, the tale and the fantastic. The present paper analyses three organising devices of the fantastic in this tale: firstly, the use of historically grounded, spatiotemporal references that lend verisimilitude to the events narrated; secondly, the role of the journey as a structuring...

  3. Nuevo yacimiento de flora Albense en la vertiente sur de la Sierra de Guadarrama. Soto del Real (Madrid)

    OpenAIRE

    1986-01-01

    A new superior Albian - Cenomanian fossil flore locality are described for the first time on. the Sierra Guadarrama (Madrid). Between all the numerous specimens there found. stand out, due to their abundancy, the ones belonging to various species of Cycadales and Coniferals, accompanied by the Filicales, Lycopodiales and the Angiosperms Monocotiledonae and Dicotilodenae of the Policarpicales and Rosales orders. Two species of the Filicales orderGleichenites giesekianus (Hee...

  4. Modeling the Potential Distribution of Picea chihuahuana Martínez, an Endangered Species at the Sierra Madre Occidental, Mexico

    OpenAIRE

    2015-01-01

    Species distribution models (SDMs) help identify areas for the development of populations or communities to prevent extinctions, especially in the face of the global environmental change. This study modeled the potential distribution of the tree Picea chihuahuana Martínez, a species in danger of extinction, using the maximum entropy modeling method (MaxEnt) at three scales: local, state and national. We used a total of 38 presence data from the Sierra Madre Occidental. At the local scale, we...

  5. Mapping Webs of Information, Conversation, and Social Connections: Evaluating the Mechanics of Collaborative Adaptive Management in the Sierra Nevada Forests

    OpenAIRE

    2014-01-01

    Managing within social-ecological systems at the landscape scale, such as in the national forests of the Sierra Nevada of California, is challenging to natural resource managers (e.g. the U.S. Forest Service) due to the uncertainties in natural processes and the complexities in social dynamics. Collaborative adaptive management (CAM) has been recently adopted as a viable strategy to diminish uncertainties in natural processes through iterative policy experimentations and adaptations, as well ...

  6. Lassa hemorrhagic fever in a late term pregnancy from northern sierra leone with a positive maternal outcome: case report

    Directory of Open Access Journals (Sweden)

    Bangura James J

    2011-08-01

    Full Text Available Abstract Lassa fever (LF is a devastating viral disease prevalent in West Africa. Efforts to take on this public health crisis have been hindered by lack of infrastructure and rapid field deployable diagnosis in areas where the disease is prevalent. Recent capacity building at the Kenema Government Hospital Lassa Fever Ward (KGH LFW in Sierra Leone has lead to a major turning point in the diagnosis, treatment and study of LF. Herein we present the first comprehensive rapid diagnosis and real time characterization of an acute hemorrhagic LF case at KGH LFW. This case report focuses on a third trimester pregnant Sierra Leonean woman from the historically non-endemic Northern district of Tonkolili who survived the illness despite fetal demise. Employed in this study were newly developed recombinant LASV Antigen Rapid Test cassettes and dipstick lateral flow immunoassays (LFI that enabled the diagnosis of LF within twenty minutes of sample collection. Deregulation of overall homeostasis, significant hepatic and renal system involvement, and immunity profiles were extensively characterized during the course of hospitalization. Rapid diagnosis, prompt treatment with a full course of intravenous (IV ribavirin, IV fluids management, and real time monitoring of clinical parameters resulted in a positive maternal outcome despite admission to the LFW seven days post onset of symptoms, fetal demise, and a natural still birth delivery. These studies solidify the growing rapid diagnostic, treatment, and surveillance capabilities at the KGH LF Laboratory, and the potential to significantly improve the current high mortality rate caused by LF. As a result of the growing capacity, we were also able to isolate Lassa virus (LASV RNA from the patient and perform Sanger sequencing where we found significant genetic divergence from commonly circulating Sierra Leonean strains, showing potential for the discovery of a newly emerged LASV strain with expanded geographic

  7. Lassa hemorrhagic fever in a late term pregnancy from northern Sierra Leone with a positive maternal outcome: case report.

    Science.gov (United States)

    Branco, Luis M; Boisen, Matt L; Andersen, Kristian G; Grove, Jessica N; Moses, Lina M; Muncy, Ivana J; Henderson, Lee A; Schieffellin, John S; Robinson, James E; Bangura, James J; Grant, Donald S; Raabe, Vanessa N; Fonnie, Mbalu; Zaitsev, Eleina M; Sabeti, Pardis C; Garry, Robert F

    2011-08-15

    Lassa fever (LF) is a devastating viral disease prevalent in West Africa. Efforts to take on this public health crisis have been hindered by lack of infrastructure and rapid field deployable diagnosis in areas where the disease is prevalent. Recent capacity building at the Kenema Government Hospital Lassa Fever Ward (KGH LFW) in Sierra Leone has lead to a major turning point in the diagnosis, treatment and study of LF. Herein we present the first comprehensive rapid diagnosis and real time characterization of an acute hemorrhagic LF case at KGH LFW. This case report focuses on a third trimester pregnant Sierra Leonean woman from the historically non-endemic Northern district of Tonkolili who survived the illness despite fetal demise. Employed in this study were newly developed recombinant LASV Antigen Rapid Test cassettes and dipstick lateral flow immunoassays (LFI) that enabled the diagnosis of LF within twenty minutes of sample collection. Deregulation of overall homeostasis, significant hepatic and renal system involvement, and immunity profiles were extensively characterized during the course of hospitalization. Rapid diagnosis, prompt treatment with a full course of intravenous (IV) ribavirin, IV fluids management, and real time monitoring of clinical parameters resulted in a positive maternal outcome despite admission to the LFW seven days post onset of symptoms, fetal demise, and a natural still birth delivery. These studies solidify the growing rapid diagnostic, treatment, and surveillance capabilities at the KGH LF Laboratory, and the potential to significantly improve the current high mortality rate caused by LF. As a result of the growing capacity, we were also able to isolate Lassa virus (LASV) RNA from the patient and perform Sanger sequencing where we found significant genetic divergence from commonly circulating Sierra Leonean strains, showing potential for the discovery of a newly emerged LASV strain with expanded geographic distribution

  8. Geographic Patterns and Stand Variables Influencing Growth and Vigor of Populus tremuloides in the Sierra Nevada (USA)

    OpenAIRE

    2012-01-01

    Awareness of geographic patterns and stand variables that influence tree growth will help forest managers plan appropriate management and monitoring strategies. We quantified influences of stand location, species composition, stand density, and tree size on aspen tree growth and vigor around the Lake Tahoe Basin in the Sierra Nevada Mountains of California and Nevada, USA. Radial growth data were taken from increment cores. Aspen trees on the south and west sides of the lake grew 20–25% faste...

  9. Photogrammetric Methodology for the Production of Geomorphologic Maps: Application to the Veleta Rock Glacier (Sierra Nevada, Granada, Spain)

    OpenAIRE

    José Jesús Guerrero; Javier de Matías; José Juan de Sanjosé; Gonzalo López-Nicolás; Carlos Sagüés

    2009-01-01

    In this paper we present a stereo feature-based method using SIFT (Scale-invariant feature transform) descriptors. We use automatic feature extractors, matching algorithms between images and techniques of robust estimation to produce a DTM (Digital Terrain Model) using convergent shots of a rock glacier.The geomorphologic structure observed in this study is the Veleta rock glacier (Sierra Nevada, Granada, Spain). This rock glacier is of high scientific interest because it is the southernmost ...

  10. Polychlorinated biphenyls and toxaphene in Pacific tree frog tadpoles (Hyla regilla) from the California Sierra Nevada, USA.

    Science.gov (United States)

    Angermann, Jeffrey E; Fellers, Gary M; Matsumura, Fumio

    2002-10-01

    Pacific tree frog (Hyla regilla) tadpoles were collected throughout the Sierra Nevada mountain range, California, USA, in 1996 and 1997 and analyzed for the presence of polychlorinated biphenyls (PCBs) and toxaphene. Whole-tadpole sigma PCB levels ranged from 244 ng/g (wet wt) at lower elevations on the western slope to 1.6 ng/g high on the eastern slope, whereas sigma toxaphene levels ranged from 15.6 to 1.5 ng/g. Linear regression of PCB and toxaphene residue levels versus elevation indicated a significant relationship, with an r2 value of 0.33 for PCB and 0.45 for toxaphene indicating a significant elevation effect on PCB and toxaphene bioaccumulation in Sierra Nevada H. regilla. Tadpole samples from sites in east-facing versus west-facing drainage basins showed significant differences in PCB and toxaphene residue levels, suggesting the possibility of a rain-shadow effect in the long-range atmospheric transport of these contaminants to the Sierra Nevada Mountains.

  11. Paleozoic subduction complex and Paleozoic-Mesozoic island-arc volcano-plutonic assemblages in the northern Sierra terrane

    Science.gov (United States)

    Hanson, Richard E.; Girty, Gary H.; Harwood, David S.; Schweickert, Richard A.

    2000-01-01

    This field trip provides an overview of the stratigraphic and structural evolution of the northern Sierra terrane, which forms a significant part of the wall rocks on the western side of the later Mesozoic Sierra Nevada batholith in California. The terrane consists of a pre-Late Devonian subduction complex (Shoo Fly Complex) overlain by submarine arc-related deposits that record the evolution of three separate island-arc systems in the Late Sevonian-Early Mississippian, Permian, and Late Triassic-Jurassic. The two Paleozoic are packages and the underlying Shoo Fly Complex have an important bearing on plate-tectonic processes affecting the convergent margin outboard of the Paleozoic Cordilleran miogeocline, although their original paleogeographic relations to North America are controversial. The third arc package represents an overlap assemblage that ties the terrane to North America by the Late Triassic and helps constrain the nature and timing of Mesozoic orogenesis. Several of the field-trip stops examine the record of pre-Late Devonian subduction contained in the Shoo Fly Complex, as well as the paleovolcanology of the overlying Devonian to Jurassic arc rocks. Excellent glaciated exposures provide the opportunity to study a cross section through a tilted Devonian volcano-plutonic association. Additional stops focus on plutonic rocks emplaced during the Middle Jurassic arc magmatism in the terrane, and during the main pulse of Cretaceous magmatism in the Sierra Nevada batholith to the east.

  12. El Rosario: un asentamiento prehispánico en "la sierra de los pijao", municipio de Buga, cordillera Central (Colombia

    Directory of Open Access Journals (Sweden)

    Eduardo Forero Lloreda

    2009-07-01

    In the Colombian Andean Central Range belonging to over the Department of Valle in the origins of Cofre river, at El Rosario (Municipality of Buga, there are certain cultural ar- chaeological characteristics that show the evidence of pre–Hispanic occupation, which occurred close to the moment of the first contact with the Spanish invasion. Historical sources of this contact make reference to the fact that the Central Mountain Range was called “Sierra de los pijaos” or “Sierra alta de los pijaos” and was considered the territorial limit since the foundation chronicles of the city of Buga. This is the same border that was used in those days, when Spanish invaders could not trespass due to the occupation of groups that were against the invasion. There is also information about explorations along the middle river stream Guadalajara –river in the same terri- torial limits; that is, the western branch of the Central Mountain Range. The fact that these establishments are found in the limits of the occupation might mean that the- re are two different patterns. The first one is El Rosario (which shares similarities in style with Chaparral– Tolima and the second one is El Janeiro, which has late charac- teristics of what is known as Cauca Medio and Quimbaya. This document reports the unpublished archaeological explorations for this archaeological Colombian region. Keywords: central mountain range, Sierra de los Pijao, territorial limit, Cauca Valley, late settlements

  13. Rhynchonellides (Brachiopodes du Jurassique moyen de la Sierra de los Cameros province de Soria. Espagne

    Directory of Open Access Journals (Sweden)

    Laurin, B.

    1985-12-01

    Full Text Available The outcrops of middle Bathonian and lower Callovian of the Sierra de los Cameros contains 4 rhynchonellids species with large morphologic variability. These species, one of which is new, are defined by both qualitative and quantitative analysis, Questions resulting ofvariability of external and internal features are discussed . The two bathonian species , Rhacthorhynchia cf. dumortieri(SZAJN. and Globirhynchia pinillensis nov. sp., are close of north african forms whereas the callovian ones, Rhynchonelloidella spathica (LMK and Septaliphoria mourdoni LAURIN, are still well known in the north-tethysian european realm. Their occurrence in Spain confirm their biostratigraphic interest.

    Les gisements du Bathonien supérieur el du Callovien inférieur de la Sierra de los Cameros renferment quatre espèces de rhynchonelles a large variabilité morphologique, Ces espèces, dont une nouvelle, sont étudiées et définies par des analyses qualitatives et quantitatives. Les problèmes posés par la variabilité de la morphologie externe et des structures internes sont discutés, Les deux espèces bathoniennes Rhacthorhynchia cf. dumortieri(SZAJN. et Globirhynchia pinillensis nov. sp, présentent des affínités avec des faunes d'Afrique du Nord tandis que Rhynchonelloidella spathica (LMK et Septaliphoria mourdoni LAURIN sont dejà bien connues dans le Callovien européen nord-téthysien. Leur présence en Espagne confirme leur intérêt biostratigraphique.
    En los yacimientos del Bathoniense superior y del Calloviense inferior de la Sierra de los Cameros se encuentran cuatro especies de Rhynchonellidae. Presentan una variabilidad morfológica amplia y, además, una de ellas es nueva. El estudio y la definición de todas se efectuaron por análisis cuantitativos y cualitativos. También se discuten aquí los problemas planteados por la variabilidad de la morfología externa y de las

  14. Simulating 3-D radiative transfer effects over the Sierra Nevada mountains using WRF

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    Y. Gu

    2012-08-01

    Full Text Available A surface solar radiation parameterization based on deviations between 3-D and conventional plane-parallel radiative transfer models has been incorporated into the Weather Research and Forecasting (WRF model to understand the solar insolation over mountain/snow areas and to investigate the impact of the spatial and temporal distribution and variation of surface solar fluxes on land-surface processes. Using the Sierra Nevada in the Western United States as a testbed, we show that mountain effect could produce up to −50 to +50 W m−2 deviations in the surface solar fluxes over the mountain areas, resulting in a temperature increase of up to 1 °C on the sunny side. Upward surface sensible and latent heat fluxes are modulated accordingly to compensate for the change in surface solar fluxes. Snow water equivalent and surface albedo both show decreases on the sunny side of the mountains, indicating more snowmelt and hence reduced snow albedo associated with more solar insolation due to mountain effect. Soil moisture increases on the sunny side of the mountains due to enhanced snowmelt, while decreases on the shade side. Substantial differences are found in the morning hours from 8–10 a.m. and in the afternoon around 3–5 p.m., while differences around noon and in the early morning and late afternoon are comparatively smaller. Variation in the surface energy balance can also affect atmospheric processes, such as cloud fields, through the modulation of vertical thermal structure. Negative changes of up to −40 g m−2 are found in the cloud water path, associated with reductions in the surface insolation over the cloud region. The day-averaged deviations in the surface solar flux are positive over the mountain areas and negative in the valleys, with a range between −12~12 W m−2. Changes in sensible and latent heat fluxes and surface skin temperature follow the solar insolation pattern. Differences in the

  15. Groundwater-surface water interactions in montane meadows of the Sierra Nevada, California

    Science.gov (United States)

    Lucas, R. G.; Conklin, M. H.

    2012-12-01

    Meadows often lie in low gradient, groundwater fed terrain of the Sierra Nevada. These settings result in near saturated conditions for much of the year, shallow groundwater tables, and groundwater discharge to surface flow. Our hypothesis is that groundwater fluctuations integrate watershed processes rather than meadow specific processes. Meadow characteristics are in contrast to the adjacent forested landscapes, where soils go dry in the summer, groundwater tables are much deeper, and some fraction of soil water is lost to deeper percolation. We utilize a series water column data from monitoring wells and piezometers in two meadows, soil moisture and snow depth data from nodes in the associated catchment, located within the Southern Sierra Critical Zone Observatory, from water years 2008-2012. Water samples from wells and associated streams were analyzed for major ions and stable water isotopes. Results from the monitoring wells and piezometers show groundwater tables and pressure heads that are highest during snowmelt and decrease over the summer growing season; inter-annual variation is correlated to total accumulated precipitation for the given water year. Groundwater elevations exhibit diurnal fluctuations influenced by snowmelt and evapotranspiration (ET) processes in the spring, transitioning to an ET dominated signal during the summer growing season. These fluctuations are of greatest magnitude near the meadow-forest boundary and least near the center of the meadow. ET signals continue after the meadow vegetation senesces, suggesting influences from the adjacent forested landscape. Deep piezometers (>2.5 m depth) do not exhibit fluctuation at the daily time scale while shallower piezometers (edge and meadow center, groundwater discharge is strongest during snow melt with a decrease as the summer growing season progresses. The near edge pressure head data show that the direction of groundwater flux changes to indicate groundwater recharge by fall. The near

  16. Structure of the Alpujarrides on the southern and eastern border of the Sierra de Lújar

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    Tubía, J. M.

    1990-08-01

    Full Text Available The Alpujarride complex located to the South of the Sierra Nevada and extending between Motril and Adra is formed of five nappes, which in ascending order are: Lújar, Cástaras, Alcázar, Murtas and Adra. These five nappes display a structure that is the result of several overlapping events. Firstly, they reflect a process of ductile shearing associated with a mylonitic foliation and a mylonitic lineation with a N4üo E average orientation. Following this, an episode of translation towards the North has been recorded; this occurred under more superficial conditions and developed gouges and fault breccias. Associated with this episode are locally developed folds, which did not give rise to a mineral blastesis. Afterwards, the late deformations occurred, affecting the whole ofthe ensemble. Of these, the most important are those that originated folds with a N-S axis, verging towards the West and the normal faults. The extensional faults towards the South would be encompassed in this sectionEl Complejo Alpujárride situado al Sur de Sierra Nevada y comprendido entre Motril y Adra, está formado por cinco mantos que son, en orden ascendente: Lújar, Cástaras, Alcázar, Murtas y Adra. Estos cinco mantos presentan una estructuración que es el resultado de varios acontecimientos superpuestos. En primer lugar, reflejan un proceso de cizallamiento dúctil hacia el NE, que lleva asociado una foliación milonítica, de orientación media N4üo E. A continuación se ha registrado un episodio de traslaciones hacia el Norte, en condiciones más superficiales, que desarrolla brechas y harinas de falla. Asociado a este episodio se desarrollan localmente pliegues, que no dan lugar a una blastesis mineral. Con posterioridad se producen las deformaciones tardías, que afectan a todo el conjunto. De ellas, las más sobresalientes son las que originan pliegues de eje N-S, vergentes al Oeste y las fallas normales. Las fallas extensionales hacia el Sur quedar

  17. Thrust kinematics deduced by primary and secondary magnetizations in the Internal Sierras (Central Pyrenees, Spain)

    Science.gov (United States)

    Oliva, B.; Pueyo, E.

    2003-04-01

    The Central Southern Pyrenees are composed (from N to S) by the Axial Zone (made by several basement-involved nappes; (Gavarnie and Guarga), the Internal Sierras (IS) fold and thrust belt (Larra and Monte Perdido units), the Jaca piggyback basin (turbiditic and molassic) and the External Sierras. Several paleomagnetic studies have been carried out during the last decades in all units except for the IS. Different amounts of rotation were reported, usually from primary directions. This work shows paleomagnetic results derived from recent investigations in the IS. 78 sites were sampled in different thrust sheets in the Larra and Monte Perdido units. Sites were collected in Upper Cretaceous rocks; all of them were homogeneously distributed along the range strike. A N-S section through the Eocene turbiditic basin was also done (9 sites) to link our results to previous data. Stepwise thermal demagnetization every 25-50^oC was performed to unravel the NRM components. Magnetic mineralogy essays (IRM, IST and low temperature) confirm magnetite as the major magnetic carrier. Two paleomagnetic components can be distinguished; A) an intermediate direction unblocking from 350^o to 450^oC and B) a high temperature component (from 500^o -575^oC). The B component displays two polarities and a positive fold and reverse tests whereas the A component shows only reverse polarity and a pervasive negative fold test. The A component has been also found in the Eocene transect. Two major clues help to constrain the remagnetization age; on one hand the deformation age (Early-Middle Eocene in the Larra and Monte Perdido units) and, on the other hand, the age of the turbiditic rocks (Middle Eocene). Therefore the remagnetization process took place by the end of the IS thrust system configuration or in a later period. Since the rotation detected by the A and B components are similar, the rotation age can be constrained as younger than the remagnetization. All these deductions have important

  18. GuMNet - A high altitude monitoring network in the Sierra de Guadarrama (Madrid, Spain)

    Science.gov (United States)

    Santolaria-Canales, Edmundo

    2016-04-01

    The Guadarrama Monitoring Network (GuMNet) is an observational infrastructure focused on monitoring the state of the atmosphere and the ground in the Sierra de Guadarrama, 50 km NW of the city of Madrid. The network is composed of10 stations ranging from low altitude (900 m a.s.l.) to high mountain climate (2400 m a.s.l.). The atmospheric instrumentation includes sensors for air temperature, air humidity, 4-component net radiation, precipitation, snow height and wind speed and direction. The surface and subsurface infrastructure includes temperature and humidity sensors distributed in 9 trenches up to a maximum of 1 m depth and additionally temperature sensors in 15 PVC cased boreholes down to 20 m and 2 m with a higher vertical resolution close to the surface. All stations are located in exposed open areas except for one site that is in a forested area for measuring air-ground fluxes under forest conditions. High altitude sites are focused on periglacial areas and lower altitude sites have emphasis on pastures. One of the low altitude sites is equipped with a 10 m high tower with 3D sonic anemometers and a CO2/H2O analyzer that will allow the sampling of wind profiles and H2O and CO2 eddy covariance fluxes, important for estimation of CO2 and energy exchanges over complex vegetated surfaces. The network is connected via general packet radio service to the central lab in the Campus of Excellence of Moncloa and management software has been developed to handle the operation of the infrastructure. The data provided by GuMNet will help to improve the characterization of atmospheric variability from turbulent scales to meteorology and climate at high mountain areas, as well as land-atmosphere interactions. The network information aims at meeting the needs of accuracy to be used for biological, agricultural, hydrological, meteorological and climatic investigations in this area with relevance for ecosystem oriented studies. This setup will complement the broader network

  19. Significado de las deformaciones internas en las peridotitas de Sierra Alpujata (Málaga

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    Tubía, J. M.

    1985-12-01

    Full Text Available The Ronda peridotites rest at the base of the Los Reales nappe (Alpujarride Complex, Betic Chain. Two successive plastic deformations are imprinted in the Sierra Alpujata peridotites. The first one is a high temperature (> 1000º C -low stress (0.3-0.5 Kb deformation as show by coarse-grained porphyroclastic lherzolites. This deformation can take place by mantle flow in a spreading zone related to continental rifting. The second deformation. at low temperature (~8000º C and high stress (1-2 Kb, erase the last one at the edge rones of the peridotite sheet, giving the mylonitisation of peridotites and the development of dynamothermal aureoles in the wall rocks, This deformation is due to the thrusting of a mantle slab over the continental crust. The kinematic analysis of the high and low-temperature ultrabasic tectonites provides, in the present position of the Betic Chain a N 70º E direction for the paleorift. The peridotite thrusting is practically realized in the same direction, from the WSW to the ENE.

    Las peridotitas de Ronda (Málaga forman la base del manto de Los Reales (Alpujárrides, Cordilleras Béticas. Las rocas ultrabásicas del macizo de Sierra Alpujata permiten reconocer dos deformaciones plásticas sucesivas. La primera es una deformación de altas temperaturas (> 1.000ºC y bajos esfuerzos (0.3-0.5 Kb que se conserva en lherzolitas con textura porfiroclástica de grano grueso. Esta deformación puede atribuirse al flujo del manto en una zona de expansión relacionada a procesos de "rifting" continental. La segunda deformación, de bajas temperaturas (~800ºC y altos esfuerzos (1-2 Kb, oblitera a la anterior en las zonas de borde de la lámina peridotítica, produciendo la milonitización de las peridotitas y el desarrollo de aureolas dinamotérmicas en los materiales encajantes. Esta deformación se debe al cabalgamiento de una escama del manto sobre la corteza continental. El análisis cinemático de las tectonitas

  20. Diamonds, a resource curse? The case of Kono District in Sierra Leone

    Science.gov (United States)

    Wilson, Sigismond Ayodele

    Using an actor-oriented approach to political ecology integrated with theory on the social production of scale, this dissertation examines the extent to which diamond exploitation constitutes a resource curse in Sierra Leone, with Kono District as a case-study. It uses social survey methods and remote sensing analysis of Landsat images to (1) evaluate the role of Sierra Leone's diamonds in economic development from a historical lens, (2) examine the extent to which a weak regulatory state apparatus makes a rich diamond endowment more of a curse than a blessing, (3) determine whether geographically diffuse and remotely-located diamonds are more a liability than an asset, and (4) assess whether environmental conditions are worse in diamond than in non-diamond chiefdoms. Results of the study showed that the contribution of diamonds to national economic growth declined precipitously following the politicization of diamonds and growing informalization of mining under the leadership of Siaka Stevens. Growing disenchantment combined with grievances over access to diamond resources and rights, culminating in a civil war fuelled by conflict diamonds. Findings indicated that actors capitalized on a weak regulatory state to fulfill their agendas. Illicit diamond exploitation was mainly driven by corruption, economic constraints and perverse economic incentives. Preferential land allocation to industrial mining following World Bank Group-directed national mining policy reforms and the weakness of the state in ensuring companies' adherence to mining clauses precipitated corporation-community conflicts. Study findings showed that the resource curse was acute on diggers who received less than 1 a day unlike their South American counterparts who made at least 7 daily. Results from the study demonstrate that the spatiality of diamonds also contributed to the resource curse. Illicit diamond mining was more acute in remotely located mining sites than in extractive sites closer to

  1. Geological evolution of a pleistocene rhyolitic center — Sierra La Primavera, Jalisco, México

    Science.gov (United States)

    Mahood, Gail A.

    1980-10-01

    The Sierra La Primavera volcanic complex consists of late Pleistocene comenditic lava flows and domes. ash-flow tuff, air-fall pumice, and cold caldera-lake sediments. The earliest lavas were erupted about 120,000 years ago, and were followed approximately 95,000 years ago by the eruption of about 20 km 3 of magma as ash flows that form the compositionally-zoned Tala Tuff. Collapse of the roof zone of the magma chamber led to the formation of a shallow 11-km-diameter caldera. It soon filled with water, forming a caldera lake in which sediment began to collect. At about the same time, two central domes erupted through the middle of the lake and a "giant pumice horizon", an important stratigraphic marker, was deposited. Shortly thereafter ring domes erupted along two parallel arcs: one along the northeast portion of the ring fracture, and the other crossing the middle of the lake. All these events occurred during a period of approximately 5,000-10,000 years. Sedimentation continued and a period of volcanic quiescence was marked by the deposition of some 30 m of fine-grained ashy sediments virtually free from pumice lapilli. Approximately 75,000 years ago, a new group of ring domes erupted at the southern margin of the lake. These domes are lapped by only 10-20 m of sediments, as uplift resulting from renewed insurgence of magma brought an end to the lake. This uplift culminated in the eruption, beginning approximately 60,000 years ago, of aphyric lavas along a southern arc. The youngest of these lavas erupted approximately 20,000-30,000 years ago. The four major fault systems in the Sierra La Primavera are related to caldera collapse or to uplift caused by the insurgence of the southern are magma. Steam vents and larga-discharge 65°C hot springs are associated with the faulting. Calculated equilibrium temperatures of the geothermal fluids are ˜170°C, but temperatures in excess of 240°C have been encountered in an exploratory drill hole. A seismic survey showed

  2. Delays in childhood immunization in a conflict area: a study from Sierra Leone during civil war

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    Gage George N

    2007-12-01

    Full Text Available Abstract Background Sierra Leone has undergone a decade of civil war from 1991 to 2001. From this period few data on immunization coverage are available, and conflict-related delays in immunization according to the Expanded Programme on Immunization (EPI schedule have not been investigated. We aimed to study delays in childhood immunization in the context of civil war in a Sierra Leonean community. Methods We conducted an immunization survey in Kissy Mess-Mess in the Greater Freetown area in 1998/99 using a two-stage sampling method. Based on immunization cards and verbal history we collected data on immunization for tuberculosis, diphtheria, tetanus, pertussis, polio, and measles by age group (0–8/9–11/12–23/24–35 months. We studied differences between age groups and explored temporal associations with war-related hostilities taking place in the community. Results We included 286 children who received 1690 vaccine doses; card retention was 87%. In 243 children (85%, 95% confidence interval (CI: 80–89% immunization was up-to-date. In 161 of these children (56%, 95%CI: 50–62% full age-appropriate immunization was achieved; in 82 (29%, 95%CI: 24–34% immunization was not appropriate for age. In the remaining 43 children immunization was partial in 37 (13%, 95%CI: 9–17 and absent in 6 (2%, 95%CI: 1–5. Immunization status varied across age groups. In children aged 9–11 months the proportion with age-inappropriate (delayed immunization was higher than in other age groups suggesting an association with war-related hostilities in the community. Conclusion Only about half of children under three years received full age-appropriate immunization. In children born during a period of increased hostilities, immunization was mostly inappropriate for age, but recommended immunizations were not completely abandoned. Missing or delayed immunization represents an additional threat to the health of children living in conflict areas.

  3. Observations of the diurnal and seasonal trends in nitrogen oxides in the western Sierra Nevada

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    J. G. Murphy

    2006-06-01

    Full Text Available Observations of speciated nitrogen oxides, namely NO2, total peroxy nitrates (ΣPNs, total alkyl nitrates (ΣANs, and HNO3 by thermal dissociation laser induced fluorescence (TD-LIF, and supporting chemical and meteorological measurements at Big Hill (1860 m, a high elevation site in California's Sierra Nevada Mountains, are described. From May through October, terrain-driven winds in the region routinely bring air from Sacramento, 100 km southwest of the site, upslope over oak and pine forests to Big Hill during the day, while at night, the site often samples clean, dry air characteristic of the free troposphere. Winter differs mainly in that the meteorology does not favour the buildup of Sacramento's pollution over the Sierra Nevada range, and the urban-influenced air that is seen has been less affected by biogenic VOC emissions, resulting in longer lifetime for NO2 and a predominance of the inorganic forms of nitrogen oxides.

    Summertime observations at Big Hill can be compared with those from Granite Bay, a Sacramento suburb, and from the University of California's Blodgett Forest Research Station to examine the evolution of nitrogen oxides and ozone within the urban plume. Nitrogen oxide radicals (NO and NO2, which dominate total nitrogen oxides (NOy at Granite Bay, are rapidly converted into HNO3, ΣPNs, and ΣANs, such that these compounds contribute 29, 30, and 21% respectively to the NOy budget in the plume at Big Hill. Nevertheless, the decreasing concentrations of NO2 as the plume is advected to Big Hill lead to decreases in the production rate of HNO3 and ozone. The data also demonstrate the role that temperature plays in sequestering NO2 into peroxy nitrates, effectively decreasing the rate of ozone production. The important contribution of ΣANs to NOy in the region suggests that they

  4. Exploration of long-term reanalysis of Sierra Nevada snowpack inferred from snow covered area information

    Science.gov (United States)

    Girotto, M.; Margulis, S. A.; Durand, M.

    2012-04-01

    The spatial heterogeneity of the mountain snowpack and a continuously changing climate affects a variety of processes including surface water discharge. An apparent shift in ablation time and loss of snow water equivalent (SWE) in the Sierra Nevada range in California (CA), U.S.A. has been reported from several past studies based on downstream flow and/or point scale in-situ observations records. Understanding the geophysical controls and interannual variability of the spatial patterns of snow accumulation and ablation are critical for predicting the effects of climate variability on the snowpack water storage. Therefore, a continuous space-time characterization of snow distribution that uses spatially and temporally extensive remotely sensed information is necessary to improve our ability to predict and monitor this vital resource in complex mountainous terrain. Toward this end, this research generates spatial and temporal SWE estimates over a snow-dominated watershed located in the Southern Sierra Nevada, CA. We use a reanalysis data assimilation approach that is capable of merging remotely sensed Snow Covered Area (SCA) data into snow prediction models, while at the same time accounting for the limitations of each. SCA information derived from the long-term record of Landsat-5 Thematic Mapper measurements are used. The assimilation of SCA into the land surface model, coupled together with a snow depletion model, predicts continuous (in space and time) SWE at a high spatial resolution. The resulting SWE dataset from the reanalysis framework, and its relation to physiographic properties, is studied to explore specific information related to how snow accumulation and snow melt has evolved and been effected by climate variability and change. In particular, the analysis focuses on highlighting how patterns related to different physiographic components respond to observed climate signals (e.g. Pacific Decadal Oscillation (PDO) and the Oceanic El Niño Index (ONI)) and

  5. Timber harvest effect on soil moisture in the southern Sierra Nevada: Is there a measurable impact?

    Science.gov (United States)

    Meadows, M. W.; Bales, R. C.; Conklin, M. H.; Goulden, M.; Hartsough, P. C.; Hopmans, J. W.; Hunsaker, C. T.; Lucas, R. G.; Malazian, A. I.

    2013-12-01

    We monitored soil-moisture storage, evapotranspiration and streamflow in a Sierra Nevada mixed-conifer forest for three post-snowmelt spring/summer seasons during water years 2010-2013. We measured volumetric water content using a COsmic-ray Soil Moisture Observing Systems (COSMOS) to estimate shallow soil-moisture storage and an eddy-covariance flux tower to measure evapotranspiration, covering an area of about 20 ha. Soil-moisture sensors were also strategically placed at depths of 10, 30, 60 and 90 cm at 30 locations in and around the COSMOS and tower footprints. Timber harvest occurred during the summer of 2012, involving uneven-age thinning limited to trees less than 76.2 cm diameter at breast height (DBH). Timber harvest intensity varied by tree size class: approximately 39% of the trees 0 to 25.5 cm DBH, 21% of the trees 25.5 to 50.8 cm DBH, and 4% of trees 50.8-76.2 cm DBH. Merchantable timber removed from the site was about 81-100 cubic m per ha. Annual evapotranspiration was similar for all four years, averaging about 80 cm each year, despite large variability in annual precipitation amounts. Annual evapotranspiration was about 10% lower following harvest. However, 2012 and 2013 were both dry years. Water year 2011 was one of the wettest years on record - approximately 200 cm of precipitation - while 2012 was one of the driest with 70 cm of precipitation. Each year soil desiccation immediately followed snow-cover depletion, dropping from field capacity by about 20% volumetric water content over a 3-month period. The rate of soil-water loss was about the same for all years. In 2012 and 2013 the dates of snow disappearance were 2-3 months earlier than in 2011. About half of the annual total evapotranspiration for 2010-2012 occurred during the 3-month period following snowmelt. Each year, total summer precipitation was only 4-6 cm. Thus soil-water storage derived from snowmelt and rainfall provides much of the moisture for evapotranspiration in the mixed

  6. Igneous phenocrystic origin of K-feldspar megacrysts in granitic rocks from the Sierra Nevada batholith

    Science.gov (United States)

    Moore, J.G.; Sisson, T.W.

    2008-01-01

    Study of four K-feldspar megacrystic granitic plutons and related dikes in the Sierra Nevada composite batholith indicates that the megacrysts are phenocrysts that grew in contact with granitic melt. Growth to megacrystic sizes was due to repeated replenishment of the magma bodies by fresh granitic melt that maintained temperatures above the solidus for extended time periods and that provided components necessary for K-feldspar growth. These intrusions cooled 89-83 Ma, are the youngest in the range, and represent the culminating magmatic phase of the Sierra Nevada batholith. They are the granodiorite of Topaz Lake, the Cathedral Peak Granodiorite, the Mono Creek Granite, the Whitney Granodiorite, the Johnson Granite Porphyry, and the Golden Bear Dike. Megacrysts in these igneous bodies attain 4-10 cm in length. All have sawtooth oscillatory zoning marked by varying concentration of BaO ranging generally from 3.5 to 0.5 wt%. Some of the more pronounced zones begin with resorption and channeling of the underlying zone. Layers of mineral inclusions, principally plagioclase, but also biotite, quartz, hornblende, titanite, and accessory minerals, are parallel to the BaO-delineated zones, are sorted by size along the boundaries, and have their long axes preferentially aligned parallel to the boundaries. These features indicate that the K-feldspar megacrysts grew while surrounded by melt, allowing the inclusion minerals to periodically attach themselves to the faces of the growing crystals. The temperature of growth of titanite included within the K-feldspar megacrysts is estimated by use of a Zr-in-titanite geothermometer. Megacryst-hosted titanite grains all yield temperatures typical of felsic magmas, mainly 735-760 ??C. Titanite grains in the granodiorite hosts marginal to the megacrysts range to lower growth temperatures, in some instances into the subsolidus. The limited range and igneous values of growth temperatures for megacryst-hosted titanite grains support the

  7. Observations of the diurnal and seasonal trends in nitrogen oxides in the western Sierra Nevada

    Directory of Open Access Journals (Sweden)

    J. G. Murphy

    2006-01-01

    Full Text Available Observations of speciated nitrogen oxides, namely NO2, total peroxy nitrates (ΣPNs, total alkyl nitrates (ΣANs, and HNO3 by thermal dissociation laser induced fluorescence (TD-LIF, and supporting chemical and meteorological measurements at Big Hill (1860 m, a high elevation site in California's Sierra Nevada Mountains, are described. From May through October, terrain-driven winds in the region routinely bring air from Sacramento, 100 km southwest of the site, upslope over oak and pine forests to Big Hill during the day, while at night, the site often samples clean, dry air characteristic of the free troposphere. Winter differs mainly in that the meteorology does not favour the buildup of Sacramento's pollution over the Sierra Nevada range, and the urban-influenced air that is seen has been less affected by biogenic VOC emissions, resulting in longer lifetime for NO2 and a predominance of the inorganic forms of nitrogen oxides. Summertime observations at Big Hill can be compared with those from Granite Bay, a Sacramento suburb, and from the University of California's Blodgett Forest Research Station to examine the evolution of nitrogen oxides and ozone within the urban plume. Nitrogen oxide radicals (NO and NO2, which dominate total nitrogen oxides (NOy at Granite Bay, are rapidly converted into HNO3, ΣPNs, and ΣANs, such that these compounds contribute 29, 30, and 21% respectively to the NOy budget in the plume at Big Hill. Nevertheless, the decreasing concentrations of NO2 as the plume is advected to Big Hill lead to decreases in the production rate of HNO3 and ozone. The data also demonstrate the role that temperature plays in sequestering NO2 into peroxy nitrates, effectively decreasing the rate of ozone production. The important contribution of ΣANs to NOy in the region suggests that they should be considered with regards to export of NOy from the boundary layer. Nocturnal observations of airmasses characteristic of the

  8. Hornblende-rich, high grade metamorphic terranes in the southernmost Sierra Nevada, California, and implications for crustal depths and batholith roots

    Science.gov (United States)

    Ross, Donald Clarence

    1983-01-01

    The southernmost Sierra Nevaaa widely exposes hornblende-rich, gneissic to granoblastic, amphibolite- to granulite-grade, metamorphic rocks and associated magmatic rocks, all of mid-Cretaceous age. Locally, red garnet, in part in euhedral crystals as large as 10 cm, as well as strongly pleochroic hyperstnene, characterize these rocks. These hornblende-rich rocks dominate the north slopes of the southern tail of the Sierra Nevada, but are also present as inclusion masses of various sizes in the dominantly granitic terrane to She northeast. The mafic, hornblende-rich rocks reflect a deeper crustal level than the dominantly granitic terrane to the northeast based on: 1) 'index' minerals (presence of hypersthene, coarse garnet, and brown hornblende; 2) textures (considerable ambivalence of whether individual samples are metamorphic or magmatic, 3) metamorphic grade (at least local granulite facies); and 4) the presence of migmatite, and the eviaence of local melting and mobilization. These rocks may be exposures of the upper part of the root zone and metamorphic substrate of the Sierra Nevada batholith. Xenoliths of gneiss, amphibolite, and granulite from sub-batholithic levels, that have been transported upward and preserved in volcanic rocks in the central Sierra Nevada, are similar to some exposed rocks of the southernmost Sierra Nevada. Hypersthene-bearing granulite and tonalite, as well as distinctive granofels of mid-Cretaceous age, are exposed in the western part of the Santa Lucia Range (some 300 km to the northwest across the San Andreas fault). These rocks have much in common with some of the metamorphic and magmatic rocks in the southernmost Sierra Nevada, suggesting that the two areas record similar metamorphic conditions and crustal depth. Mid-Cretaceous hypersthene granulite is rare, which makes correlation of the Santa Lucia Range and the southernmost Sierra Nevada seem attractive. Nevertheless, possibly significant petrographic anm rock distribution

  9. Seismicity patterns during a period of inflation at Sierra Negra volcano, Galápagos Ocean Island Chain

    Science.gov (United States)

    Davidge, Lindsey; Ebinger, Cynthia; Ruiz, Mario; Tepp, Gabrielle; Amelung, Falk; Geist, Dennis; Coté, Dustin; Anzieta, Juan

    2017-03-01

    Basaltic shield volcanoes of the western Galápagos islands are among the most rapidly deforming volcanoes worldwide, but little was known of the internal structure and brittle deformation processes accompanying inflation and deflation cycles. A 15-station broadband seismic array was deployed on and surrounding Sierra Negra volcano, Galápagos from July 2009 through June 2011 to characterize seismic strain patterns during an inter-eruption inflation period and to evaluate single and layered magma chamber models for ocean island volcanoes. We compare precise earthquake locations determined from a 3D velocity model and from a double difference cluster method. Using first-motion of P-arrivals, we determine focal mechanisms for 8 of the largest earthquakes (ML ≤ 1.5) located within the array. Most of the 2382 earthquakes detected by the array occurred beneath the broad (∼9 km-wide) Sierra Negra caldera, at depths from surface to about 8 km below sea level. Although outside our array, frequent and larger magnitude (ML ≤ 3.4) earthquakes occurred at Alcedo and Fernandina volcano, and in a spatial cluster beneath the shallow marine platform between Fernandina and Sierra Negra volcanoes. The time-space relations and focal mechanism solutions from a 4-day long period of intense seismicity June 4-9, 2010 along the southeastern flank of Sierra Negra suggests that the upward-migrating earthquake swarm occurred during a small volume intrusion at depths 5-8 km subsurface, but there was no detectable signal in InSAR data to further constrain geometry and volume. Focal mechanisms of earthquakes beneath the steep intra-caldera faults and along the ring fault system are reverse and strike-slip. These new seismicity data integrated with tomographic, geodetic, and petrological models indicate a stratified magmatic plumbing system: a shallow sill beneath the large caldera that is supplied by magma from a large volume deeper feeding system. The large amplitude inter

  10. Regional polyphase deformation of the Eastern Sierras Pampeanas (Argentina Andean foreland): strengths and weaknesses of paleostress inversion

    Science.gov (United States)

    Traforti, Anna; Zampieri, Dario; Massironi, Matteo; Viola, Giulio; Alvarado, Patricia; Di Toro, Giulio

    2016-04-01

    The Eastern Sierras Pampeanas of central Argentina are composed of a series of basement-cored ranges, located in the Andean foreland c. 600 km east of the Andean Cordillera. Although uplift of the ranges is partly attributed to the regional Neogene evolution (Ramos et al. 2002), many questions remain as to the timing and style of deformation. In fact, the Eastern Sierras Pampeanas show compelling evidence of a long lasting brittle history (spanning the Early Carboniferous to Present time), characterised by several deformation events reflecting different tectonic regimes. Each deformation phase resulted in further strain increments accommodated by reactivation of inherited structures and rheological anisotropies (Martino 2003). In the framework of such a polyphase brittle tectonic evolution affecting highly anisotropic basement rocks, the application of paleostress inversion methods, though powerful, suffers from some shortcomings, such as the likely heterogeneous character of fault slip datasets and the possible reactivation of even highly misoriented structures, and thus requires careful analysis. The challenge is to gather sufficient fault-slip data, to develop a proper understanding of the regional evolution. This is done by the identification of internally consistent fault and fracture subsets (associated to distinct stress states on the basis of their geometric and kinematic compatibility) in order to generate a chronologically-constrained evolutionary conceptual model. Based on large fault-slip datasets collected in the Sierras de Cordoba (Eastern Sierras Pampeanas), reduced stress tensors have been generated and interpreted as part of an evolutionary model by considering the obtained results against: (i) existing K-Ar illite ages of fault gouges in the study area (Bense et al. 2013), (ii) the nature and orientation of pre-existing anisotropies and (iii) the present-day stress field due to the convergence of the Nazca and South America plates (main shortening

  11. Primera edad U-Pb en circón usando LA-ICP-MS de un dique traquiandesítico emplazado en el granito tipo-A Los Árboles, Sierras Pampeanas Orientales First age U-Pb zircon LA-ICP-MS from trachyandesitic dyke emplaced in the A-type Los Árboles pluton, Eastern Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    Juan A Dahlquist

    2012-06-01

    Full Text Available La edad de cristalización de diques subvolcánicos emplazados en plutones graníticos carboníferos, Sierras Pampeanas Orientales, permanece incierta. La primera edad U-Pb en circón usando LA-ICP-MS obtenida en un dique que intruye al plutón Los Árboles (sierra de Fiambalá, revela una edad de cristalización de 311 ± 3 Ma.The crystallization age of subvolcanic dykes emplaced in Carboniferous granitic plutons of the Sierras Pampeanas Orientales remains uncertain. The first age precise U-Pb zircon LA-ICP-MS obtained from a dyke emplaced in the Los Árboles pluton (Sierra de Fiambalá yield a crystallization age of 311 ± 3 Ma.

  12. Los diques comendíticos de Papachacra (Catamarca: magmatismo peralcalino en sierras Pampeanas orientales The comenditic dikes from Papachacra (Catamarca: peralkaline magmatism in Eastern Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    Fernando Colombo

    2010-03-01

    Full Text Available En Papachacra (Provincia de Catamarca, NO de Argentina hay un plutón compuesto por varios tipos diferentes de granitoides de tipo A con afinidad alcalina. Las rocas más tardías son riolitas peralcalinas (comenditas, que forman diques de hasta 50 cm atravesando el granito biotítico El Portezuelo, el cual está genéticamente desvinculado. Tienen textura porfírica y están compuestas por fenocristales de feldespato potásico (Or97-98 Ab2-3 y egirina (Ac94-98 en una mesostasis afanítica de cuarzo, feldespato potásico, albita, egirina y anfíbol litífero relacionado a la flúor-ferro-leakeíta. Los minerales accesorios son ilmenita, magnetita, óxidos del grupo del pirocloro, epidoto rico en tierras raras, zircón intersticial, monacita- (Ce y un óxido de Nb-Y-Fe no identificado. El contenido de SiO2 varía entre 68,28 y 69,33%, con muy bajo Mg, Ca, Ba, Sr y Eu, y altas concentraciones de Nb (399-409 ppm, Ta (16-34 ppm, Th (46-84 ppm, Y (101-192 ppm, Zn (280-320 ppm, Ga (42-47 ppm y especialmente Zr (2324-3000 ppm. Las comenditas se intruyeron durante un evento magmático anorogénico. Un estudio isotópico (Rb-Sr de reconocimiento hecho a rocas relacionadas indica una edad de 295 + 8 Ma, con una relación 87Sr/86Sr inicial cercana a 0,7041, lo que apunta a una fuente del manto sublitosférico o la base de la corteza inferior. Estas rocas pertenecen a la clase A1 de granitos de tipo A, sugiriendo un origen relacionado a rifting o a puntos calientes, y sus relaciones de elementos trazas muestran afinidades con fundidos relacionados a basaltos de islas oceánicas. En este sentido son diferentes de todos los granitos de tipo A post-devónicos descriptos en Sierras Pampeanas Orientales.In Papachacra (Catamarca Province, NW Argentina there is a pluton composed of several different A-type granitoids that show alkaline affinities. The latest rocks are peralkaline rhyolites (comendites, which form dikes up to 50 cm thick cross-cutting the

  13. SIERRA Multimechanics Module: Aria User Manual – Version 4.40

    Energy Technology Data Exchange (ETDEWEB)

    Notz, Patrick K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Subia, Samuel Ramirez [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hopkins, Matthew M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Moffat, Harry K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Noble, David R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Okusanya, Tolulope O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-05-02

    Aria is a Galerkin finite element based program for solving coupled-physics problems described by systems of PDEs and is capable of solving nonlinear, implicit, transient and direct-to-steady state problems in two and three dimensions on parallel architectures. The suite of physics currently supported by Aria includes thermal energy transport, species transport, and electrostatics as well as generalized scalar, vector and tensor transport equations. Additionally, Aria includes support for manufacturing process flows via the incompressible Navier-Stokes equations specialized to a low Reynolds number (Re < 1) regime. Enhanced modeling support of manufacturing processing is made possible through use of either arbitrary Lagrangian- Eulerian (ALE) and level set based free and moving boundary tracking in conjunction with quasi-static nonlinear elastic solid mechanics for mesh control. Coupled physics problems are solved in several ways including fully-coupled Newton’s method with analytic or numerical sensitivities, fully-coupled Newton- Krylov methods and a loosely-coupled nonlinear iteration about subsets of the system that are solved using combinations of the aforementioned methods. Error estimation, uniform and dynamic ℎ-adaptivity and dynamic load balancing are some of Aria’s more advanced capabilities. Aria is based upon the Sierra Framework.

  14. Air Pollution and Watershed Research in the Central Sierra Nevada of California: Nitrogen and Ozone

    Directory of Open Access Journals (Sweden)

    Carolyn Hunsaker

    2007-01-01

    Full Text Available Maintaining healthy forests is the major objective for the Forest Service scientists and managers working for the U.S. Department of Agriculture. Air pollution, specifically ozone (O3 and nitrogenous (N air pollutants, may severely affect the health of forest ecosystems in the western U.S. Thus, the monitoring of air pollution concentration and deposition levels, as well as studies focused on understanding effects mechanisms, are essential for evaluation of risks associated with their presence. Such information is essential for development of proper management strategies for maintaining clean air, clean water, and healthy ecosystems on land managed by the Forest Service. We report on two years of research in the central Sierra Nevada of California, a semi-arid forest at elevations of 1100–2700 m. Information on O3 and N air pollutants is obtained from a network of 18 passive samplers. We relate the atmospheric N concentration to N concentrations in streams, shallow soil water, and bulk deposition collectors within the Kings River Experimental Watershed. This watershed also contains an intensive site that is part of a recent Forest Service effort to calculate critical loads for N, sulfur, and acidity to forest ecosystems. The passive sampler design allows for extensive spatial measurements while the watershed experiment provides intensive spatial data for future analysis of ecosystem processes.

  15. Geant4 simulation of the solar neutron telescope at Sierra Negra, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, L.X., E-mail: xavier@geofisica.unam.m [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, 04510 D.F. (Mexico); Sanchez, F. [Comision Nacional de Energia Atomica, 1429 Buenos Aires (Argentina); Valdes-Galicia, J.F. [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, 04510 D.F. (Mexico)

    2010-02-01

    The solar neutron telescope (SNT) at Sierra Negra (19.0 deg. N, 97.3 deg. W and 4580 m.a.s.l) is part of a worldwide network of similar detectors (Valdes-Galicia et al., (2004)). This SNT has an area of 4 m{sup 2}; it is composed by four 1 mx1 mx30 cm plastic scintillators (Sci). The Telescope is completely surrounded by anti-coincidence proportional counters (PRCs) to separate charged particles from the neutron flux. In order to discard photon background it is shielded on its sides by 10 mm thick iron plates and on its top by 5 mm lead plates. It is capable of registering four different channels corresponding to four energy deposition thresholds: E>30, >60, >90 and >120 MeV. The arrival direction of neutrons is determined by gondolas of PRCs in electronic coincidence, four layers of these gondolas orthogonally located underneath the SNT, two in the NS direction and two in the EW direction. We present here simulations of the detector response to neutrons, protons, electrons and gammas in range of energies from 100 to 1000 MeV. We report on the detector efficiency and on its angular resolution for particles impinging the device with different zenith angles. The simulation code was written using the Geant4 package (Agostinelli et al., (2003)), taking into account all relevant physical processes.

  16. Ten Years of Forest Cover Change in the Sierra Nevada Detected Using Landsat Satellite Image Analysis

    Science.gov (United States)

    Potter, Christopher S.

    2014-01-01

    The Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) methodology was applied to detected changes in forest vegetation cover for areas burned by wildfires in the Sierra Nevada Mountains of California between the periods of 1975- 79 and 1995-1999. Results for areas burned by wildfire between 1995 and 1999 confirmed the importance of regrowing forest vegetation over 17% of the combined burned areas. A notable fraction (12%) of the entire 5-km (unburned) buffer area outside the 1995-199 fires perimeters showed decline in forest cover, and not nearly as many regrowing forest areas, covering only 3% of all the 1995-1999 buffer areas combined. Areas burned by wildfire between 1975 and 1979 confirmed the importance of disturbed (or declining evergreen) vegetation covering 13% of the combined 1975- 1979 burned areas. Based on comparison of these results to ground-based survey data, the LEDAPS methodology should be capable of fulfilling much of the need for consistent, low-cost monitoring of changes due to climate and biological factors in western forest regrowth following stand-replacing disturbances.

  17. Impact of Summer Cattle Grazing on the Sierra Nevada Watershed: Aquatic Algae and Bacteria

    Directory of Open Access Journals (Sweden)

    Robert W. Derlet

    2012-01-01

    Full Text Available Introduction. We evaluated periphytic algal and microbial communities to assess the influence of human and cattle impact on Sierra water quality. Methods. 64 sites (lakes and streams from Lake Tahoe to Sequoia National Park, California were sampled for suspended indicator bacteria and algae following standardized procedures. The potential for nonpoint pollution was divided into three categories: cattle-grazing areas (C, recreation use areas (R, or remote wildlife areas (W. Results. Periphyton was found at 100% of C sites, 89% of R sites, but only 25% of W sites. Eleven species of periphytic algae were identified, including Zygnema, Ulothrix, Chlorella, Spirogyra, mixed Diatoms, and Cladophoria. Mean benthic algae coverage was 66% at C sites compared to 2% at W sites (100 CFU/100 mL: C = 91%, R = 8%, W = 0 (<0.05. Conclusion. Higher periphytic algal biomass and uniform presence of periphyton-attached E. coli corresponded to watersheds exposed to summer cattle grazing. These differences suggest cattle grazing compromises water quality.

  18. Calibrating Late Quaternary terrestrial climate signals: radiometrically dated pollen evidence from the southern Sierra Nevada, USA

    Science.gov (United States)

    Litwin, Ronald J.; Smoot, Joseph P.; Durika, Nancy J.; Smith, George I.

    1999-01-01

    We constructed a radiometrically calibrated proxy record of Late Pleistocene and Holocene climate change exceeding 230,000 yr duration, using pollen profiles from two cores taken through age-equivalent dry lakes - one core having greater age control (via 230Th alpha mass-spectrometry) and the other having greater stratigraphic completeness. The better dated of these two serial pollen records (Searles Lake) served as a reference section for improving the effective radiometric age control in a nearby and more complete pollen record (Owens Lake) because they: (1) are situated ~90 km apart in the same drainage system (on, and immediately leeward of, the eastern flank of the Sierra Nevada), and (2) preserved strikingly similar pollen profiles and concordant sequences of sedimentological changes. Pollen assemblages from both lakes are well preserved and diverse, and document serial changes in Late Pleistocene and Holocene plant zone distribution and composition in the westernmost Great Basin; they consist of taxa now inhabiting montane forest, woodland, steppe, and desert-scrub environments. The studied core intervals are interpreted here to be the terrestrial equivalent of marine δ18O stages 1 through 9; these pollen profiles now appear to be among the best radiometrically dated Late Pleistocene records of terrestrial climate change known.

  19. Long Valley caldera and the UCERF depiction of Sierra Nevada range-front faults

    Science.gov (United States)

    Hill, David P.; Montgomery-Brown, Emily K.

    2015-01-01

    Long Valley caldera lies within a left-stepping offset in the north-northwest-striking Sierra Nevada range-front normal faults with the Hilton Creek fault to the south and Hartley Springs fault to the north. Both Uniform California Earthquake Rupture Forecast (UCERF) 2 and its update, UCERF3, depict slip on these major range-front normal faults as extending well into the caldera, with significant normal slip on overlapping, subparallel segments separated by ∼10  km. This depiction is countered by (1) geologic evidence that normal faulting within the caldera consists of a series of graben structures associated with postcaldera magmatism (intrusion and tumescence) and not systematic down-to-the-east displacements consistent with distributed range-front faulting and (2) the lack of kinematic evidence for an evolving, postcaldera relay ramp structure between overlapping strands of the two range-front normal faults. The modifications to the UCERF depiction described here reduce the predicted shaking intensity within the caldera, and they are in accord with the tectonic influence that underlapped offset range-front faults have on seismicity patterns within the caldera associated with ongoing volcanic unrest.

  20. Vegetation and climate history from Laguna de Río Seco, Sierra Nevada, southern Spain

    Science.gov (United States)

    Anderson, R. S.; Jimenez-Moreno, G.

    2010-12-01

    The largest mountain range in southern Spain - the Sierra Nevada - is an immense landscape with a rich biological and cultural heritage. Rising to 3,479 m at the summit of Mulhacén, the range was extensively glaciated during the late Pleistocene. Subsequent melting of cirque glaciers allowed formation of numerous small lakes and wetlands. One south-facing basin contains Laguna de Río Seco, a small lake at ca. 3020 m elevation, presently above potential treeline. Pollen analysis of sediment cores documents over 11,000 calendar years of vegetation change there. The early record, to ca. 5,700 cal yr BP, is dominated by pine pollen, with birch, deciduous oak, and grass, with an understory of shrubs types. Pine trees probably never grew at the elevation of the lake, but aquatic microfossils indicate lake levels were highest prior to ca. 7,800 cal yr BP, perhaps as a result of heavy winter precipitation, and early Holocene expansion of the ITCZ. Drier conditions commenced by 5,700 cal yr BP, shown by declines in wetland pollen, and increases in high elevation steppe shrubs more common today (juniper, sage, and others). The local and regional impact of humans increased substantially after ca. 2700 years ago, with the regional loss of pine forest or woodland, increases in pollen and spore types associated with pasturing, and olive cultivation at lower elevations.

  1. Sequelae and Other Conditions in Ebola Virus Disease Survivors, Sierra Leone, 2015

    Science.gov (United States)

    Vandy, Alren O.; Stretch, Rebecca; Otieno, David; Prajapati, Mukesh; Calderon, Mauricio; Vandi, Mohamed

    2017-01-01

    We rapidly assessed the health of Ebola virus disease (EVD) survivors in Kenema, Sierra Leone, by reviewing medical charts of all patients attending the Survivor Clinic of Kenema Government Hospital. Data were abstracted on signs and symptoms at every attendance. As of November 2015, a total of 621 attendances by 115 survivors with laboratory-confirmed EVD were made to the Survivor Clinic. Most (60.9%) survivors were women. Survivors’ median age was 28 years (range 0.25–70 years). Survivors attended the clinic a median of 5 times (range 1–21 times) each, and the median time from EVD discharge to attendance was 261 days (range 4–504 days). The most commonly reported signs and symptoms among the 621 attendances were headache (63.1%), fever (61.7%), and myalgia (43.3%). Because health needs of EVD survivors are complex, rapid chart reviews at survivor clinics should be repeated regularly to assess the extent of illness and prioritize service delivery. PMID:27983503

  2. STATISTICAL CHARACTERIZATION OF PRECIPITABLE WATER VAPOR AT SAN PEDRO MARTIR SIERRA IN BAJA CALIFORNIA

    Directory of Open Access Journals (Sweden)

    A. Otárola

    2009-01-01

    Full Text Available Presentamos datos del vapor de agua precipitable durante 2006 para la Sierra de San Pedro Mártir obtenidos de mediciones de la emisión atmosférica como función del ángulo de elevación por un radiómetro operando a la frecuencia de 210 GHz. Las mediciones de este radiómetro se combinan con valores de temperatura y presión atmosférica a nivel del suelo en el sitio para determinar una relación matemática para la conversión de la opacidad atmosférica al cenit a 210 GHz y la columna de vapor de agua precipitable para San Pedro Mártir. Los datos del vapor de agua precipitable se analizan estadísticamente para conocer su función de densidad de probabilidad y su distribución acumulativa, así como para determinar el número de horas continuas al año en que el vapor de agua precipitable permanece por debajo de los umbrales de 1 mm, 2 mm y 3 mm. Esta información es de interés para evaluar el desempeño de telescopios operando desde la región del óptico hasta longitudes de onda milimétricas en este sitio.

  3. TRADITIONAL USE OF A PROTECTED SPECIES (Litsea glaucescens Kunth IN THE “SIERRA DEL LAUREL

    Directory of Open Access Journals (Sweden)

    Salvador Martín Medina-Torres

    2011-05-01

    Full Text Available Whenever a natural area is proposed to be a protected area, the information that supports the proposal is usually based on the physical environmental, rather than on the social environment and on the management of natural resource. This study was conducted from May 2004 to June 2005 whit the objective to analyze the process of exploitation of Mexican Bay Leaf (Litsea glaucescens Kunth in rural communities of Sierra del Laurel, a priority area in the state of Aguascalientes, México. Thirteen semi-structured interview were applied for local collectors and seven more were applied to inhabitants of the region to understand the trends in the use of resource. Three interviews were also applied to environmental officials from federal and local institutions to know about their position regarding the use of the Mexican Bay Leaf. A participative workshop with producers and collectors was conducted to document their opinion on the status of the population of this specie. Trend in utilization of the Mexican Bay Leaf have led it to be in danger of extinction: there is not organization nor legal utilization schemes among collectors that allow regeneration; the lack of institutional coordination, along whit inefficient implementation of laws and other legal instruments to regulate the management of natural resources, has contributed so that users have not adequate risk management procedures.

  4. [Dung beetles (Coleoptera: Scarabaeinae) of the northwestern slope of the Sierra Nevada of Santa Marta, Colombia].

    Science.gov (United States)

    Martínez, Neis J; García, Héctor; Pulido, Luz A; Ospino, Deibi; Harváez, Juan C

    2009-01-01

    The community structure of dung beetles in the middle and lower river basin of the Gaira river, Sierra Nevada de Santa Marta, Colombia, is described. Four sites were selected along an altitudinal gradient of 50-940 m for sampling from June to October, 2004. Dung beetles were captured using modified pitfall traps and manual recollections. We captured 7,872 individuals belonging to 29 species, distributed in 15 genera and five tribes of Scarabaeinae. Canthon and Onthophagus were the most diverse genera, each represented by six species. The sampled sites shared the following species: Onthophagus acuminatus Harold, O. clypeatus Blanchard, O. marginicollis Harold. Bocatoma was the most diverse site with 23 species; whereas Port Mosquito presented the highest abundance, with 3,262 individuals. Seven species represented 89% of all captures: Canthidium sp., Dichotomius sp., Uroxys sp. 1, Uroxys sp. 2, O. marginicollis, O. clypeatus and O. acuminatus. Of the 29 captured species, 17 belonged to the functional group of diggers and 10 were ball-rollers. We did not observe significant among-site differences in community structure. Abiotic factors such as altitude, temperature and humidity cannot explain observed variation in community structure across sites, indicating other variables such as vegetation cover, density of the vegetation and soil type may play a role in the community structure of these insects.

  5. [Papilionoidea from Sierra de Huantla, Morelos and Puebla, México (Insecta: Lepidoptera)].

    Science.gov (United States)

    Luna-Reyes, Mercedes; Llorente-Bousquets, Jorge

    2008-12-01

    The Cuenca del Balsas region has significant biodiversity and endemicity of its herpetofauna, avifauna and vascular plants. Despite this, our knowledge of the Papilionoidea of the region is poor. We analyzed the local and temporal distribution of Papilionoidea at 24 localities in the states of Morelos and Puebla. The study sites are situated between 900 and 1300 m. a.s.l., and are composed of dry tropical forest (dtf). We recorded 8790 individuals of 83 genera and 142 species of Papilionoidea (sensu Kristensen, 1975), over 79 days of field work, with 2-4 days at each of the 24 localities. Twenty five species were newly recorded for the state of Puebla. Our data render Morelos and Puebla among the seven richest Mexican states, in terms of Papilionoidea diversity. Our results show that the Sierra de Huautla has the lowest diversity, but the highest standard abundance, compared to other Mexican regions with similar vegetation. Patterns of diversity and seasonal abundance are atypical, in that individuals of many species are unusually abundant during the wet months.

  6. ACERCA DE LA FLORA DE ANTOFAGASTA DE LA SIERRA, CATAMARCA, ARGENTINA. AMBIENTE Y PALEOAMBIENTE

    Directory of Open Access Journals (Sweden)

    M. Fernanda Rodríguez

    2013-01-01

    Full Text Available Se presenta una síntesis de los trabajos realizados sobre la identificación, anatomía y usos de especies vegetales, actuales y recuperadas en el marco de las investigaciones arqueobotánicas, llevadas a cabo en Antofagasta de la Sierra durante las campañas arqueológicas realizadas en los años 1994-2000. Se describen las transectas realizadas a partir de los sitios arqueológicos estudiados, las asociaciones vege- tales características y se presenta un listado de las especies vegetales halladas. Se describe el uso actual y se señala el nombre vernáculo para cada taxón. Luego, se presenta una descripción anatómica de tallo, raíz u hoja, dependiendo del caso, de cada uno de los taxones presentes en los sitios arqueológicos, identificados por medio de la comparación anatómica con material actual de referencia; se presentan las correspondientes fotomicrografías obtenidas con microscopio óptico y/o microscopio electrónico de barrido. Finalmente, se discute el uso, en la actualidad y en el pasado, de las especies recuperadas en los sitios arqueológicos del área de estudio, destacando aquellos aspectos que suponen cambio y continui- dad a través del tiempo.

  7. Social pathways for Ebola virus disease in rural Sierra Leone, and some implications for containment.

    Directory of Open Access Journals (Sweden)

    Paul Richards

    2015-04-01

    Full Text Available The current outbreak of Ebola Virus Disease in Upper West Africa is the largest ever recorded. Molecular evidence suggests spread has been almost exclusively through human-to-human contact. Social factors are thus clearly important to understand the epidemic and ways in which it might be stopped, but these factors have so far been little analyzed. The present paper focuses on Sierra Leone, and provides cross sectional data on the least understood part of the epidemic-the largely undocumented spread of Ebola in rural areas. Various forms of social networking in rural communities and their relevance for understanding pathways of transmission are described. Particular attention is paid to the relationship between marriage, funerals and land tenure. Funerals are known to be a high-risk factor for infection. It is suggested that more than a shift in awareness of risks will be needed to change local patterns of behavior, especially in regard to funerals, since these are central to the consolidation of community ties. A concluding discussion relates the information presented to plans for halting the disease. Local consultation and access are seen as major challenges to be addressed.

  8. Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain.

    Science.gov (United States)

    Martínez, I; Rosa, M; Arsuaga, J-L; Jarabo, P; Quam, R; Lorenzo, C; Gracia, A; Carretero, J-M; Bermúdez de Castro, J-M; Carbonell, E

    2004-07-06

    Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range.

  9. The carnivore remains from the Sima de los Huesos Middle Pleistocene site (Sierra de Atapuerca, Spain).

    Science.gov (United States)

    García, N; Arsuaga, J L; Torres, T

    1997-01-01

    Remains of carnivores from the Sima de los Huesos site representing at least 158 adult individuals of a primitive (i.e., not very speleoid) form of Ursus deningeri Von Reichenau 1906, have been recovered through the 1995 field season. These new finds extend our knowledge of this group in the Sierra de Atapuerca Middle Pleistocene. Material previously classified as Cuoninae indet, is now assigned to Canis lupus and a third metatarsal assigned in 1987 to Panthera of gombaszoegensis, is in our opinion only attributable to Panthera sp. The family Mustelidae is added to the faunal list and includes Martes sp. and a smaller species. The presence of Panthera leo cf. fossilis, Lynx pardina spelaea and Felis silvestris, is confirmed. The presence of a not very speloid Ursus deningeri, together with the rest of the carnivore assemblage, points to a not very late Middle Pleistocene age, i.e., oxygen isotope stage 7 or older. Relative frequencies of skeletal elements for the bear and fox samples are without major biases. The age structure of the bear sample, based on dental wear stages, does not follow the typical hibernation mortality profile and resembles a catastrophic profile. The site was not a natal or refuge den. The hypothesis that the site was a natural trap is the most plausible. If the Sima de los Huesos functioned as a natural trap (without an egress out), the human accumulation cannot be attributed to carnivore: activities and must be explained differently.

  10. The Sima de los Huesos crania (Sierra de Atapuerca, Spain). A comparative study.

    Science.gov (United States)

    Arsuaga, J L; Martínez, I; Gracia, A; Lorenzo, C

    1997-01-01

    The Sima de los Huesos (Sierra de Atapuerca) cranial remains found up to and including the 1995 field season are described and compared with other fossils in order to assess their evolutionary relationships. The phenetic affinities of the Sima de los Huesos crania and a large sample of Homo fossils are investigated through principal component analyses. Metrical comparisons of the Sima de los Huesos and other European and African Middle Pleistocene fossils with Neandertals are performed using Z-scores relative to the Neandertal sample statistics. The most relevant cranial traits are metrically and morphologically analyzed and cladistically evaluated. The Sima de los Huesos crania exhibit a number of primitive traits lost in Upper Pleistocene Neandertals (especially in the braincase, but also in the facial skeleton), as well as other traits that are transitional to the Neandertal morphology (particularly in the occipital bone), and features close to what is found in Neandertals (as the supraorbital morphology and midfacial prognathism). Different combinations of primitive and derived traits (shared with Neandertals) are also displayed by the other European Middle Pleistocene fossils. In conclusion, the Sima de los Huesos sample is evolutionarily related to Neandertals as well as to the other European Middle Pleistocene fossils. In our opinion, all the European Middle Pleistocene fossils belong to the Neandertal lineage, and none can be included in an Afroeuropean common ancestor of Neandertals and modern humans.

  11. Conducciones fluviales de madera desde las Sierras de Segura y Cazorla (1894-1949

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    Eduardo Araque Jiménez

    2007-01-01

    Full Text Available Las conducciones o flotaciones de maderas con origen en las Sierras de Segura y Cazorla están documentadas desde hace ya más de diez siglos. Hasta el momento la inmensa mayoría de los trabajos sobre el particular se han centrado en la etapa histórica que se extiende entre el primer tercio del siglo XVIII y mediados del siglo XIX, procurando resaltar aquellas cuestiones relativas a la organización interna de las conducciones y el peculiar modo de vida de los pineros o gancheros que las dirigían, sin reparar en otros aspectos cruciales sobre el destino de las piezas de madera transportadas o las empresas y sociedades que se encontraban detrás de este negocio. A esta clase de asuntos sólo es posible responder mediante el manejo de fuentes de información alternativas, muy poco empleadas por ahora, como el Boletín Oficial de la Provincia de Jaén.

  12. [Biodiversity of land gastropods (Mollusca) in Sierra de San Javier Park, Tucumán, Argentina].

    Science.gov (United States)

    Miranda, María José; Cuezzo, María Gabriela

    2010-09-01

    Studies related to land mollusk diversity in tropical and subtropical forests are scarce. To assess this, a study on land snail diversity of subtropical cloudforest (Yungas) and dry forest (Chaco) areas of Sierra de San Javier Park, Tucumán, Argentina, was carried out. Taxonomic identifications were performed to species level and built a species per stations data matrix to analyze diversity patterns on qualitative and quantitative samples processed from 10x10m quadrates in altitudinal transects. Non parametric analysis (ICE, ACE, Chao 1 and Chao 2) were used to estimate the true diversity of the area, as well as the degree of undersampling and spatial aggregation of the data. Diversity was also calculated using Shannon, Simpson, Whittaker and Jaccard indices. The richness of the San Javier Park was estimated to be 32 species distributed into 13 families and 21 genera. From the total number of species collected, a single one belongs to Caenogastropoda, while the rest of the species are classified into Pulmonata Stylommatophora and Systellommatophora. The most representative family was the micromollusc Charopidae, while the most relatively abundant species was another micromollusc snail, Adelopoma tucma. Richness and diversity were slightly more elevated in dry forest areas of the Chacoan Ecoregion than in cloud forest areas of Yungas. Non parametric estimators showed that the inventory was complete. Diversity values obtained were high in comparison to previously studied areas of Northwestern Argentina. The total number of specimen collected (22 169 specimens), was higher than other published studies.

  13. The Effect of Community-Based Prevention and Care on Ebola Transmission in Sierra Leone

    Science.gov (United States)

    Rogers, Braeden; Lee, Sylvia; Bhatnagar, Aarunima; Wolman, Yaron; Monasch, Roeland; Hipgrave, David; Salama, Peter; Kucharski, Adam; Chopra, Mickey

    2016-01-01

    Objectives. To examine the acceptability, use, effects on early isolation, and contribution to Ebola virus disease (EVD) transmission of Community Care Centers (CCCs), which were rapidly deployed in Sierra Leone during an accelerated phase of the 2014–2015 EVD epidemic. Methods. Focus group discussions, triads, and key informant interviews assessed acceptability of the CCCs. Facility registers, structured questionnaires, and laboratory records documented use, admission, and case identification. We estimated transmission effects by comparing time between symptom onset and isolation at CCCs relative to other facilities with the national Viral Hemorrhagic Fever data set. Results. Between November 2014 and January 2015, 46 CCCs were operational. Over 13 epidemic weeks, 6129 patients were triaged identifying 719 (12%) EVD suspects. Community acceptance was high despite initial mistrust. Nearly all patients presented to CCCs outside the national alert system. Isolation of EVD suspects within 4 days of symptoms was higher in CCCs compared with other facilities (85% vs 49%; odds ratio = 6.0; 95% confidence interval = 4.0, 9.1), contributing to a 13% to 32% reduction in the EVD reproduction number (Ro). Conclusions. Community-based approaches to prevention and care can reduce Ebola transmission. PMID:26890176

  14. Evidence for Moho-lower crustal transition depth diking and rifting of the Sierra Nevada microplate

    Science.gov (United States)

    Smith, Kenneth D.; Kent, Graham M.; Seggern, David P.; Driscoll, Neal W.; Eisses, Amy

    2016-10-01

    Lithospheric rifting most often initiates in continental extensional settings where "breaking of a plate" may or may not progress to sea floor spreading. Generally, the strength of the lithosphere is greater than the tectonic forces required for rupture (i.e., the "tectonic force paradox"), and it has been proposed that rifting requires basaltic magmatism (e.g., dike emplacement) to reduce the strength and cause failure, except for the case of a thin lithosphere (structure, each striking N45°W and dipping 50°NE. A single event at 30 km depth that locates on the implied dipping feature between the two swarms is further evidence for a single Moho-transition depth structure. We propose that basaltic or fluid emplacement at or near Moho depths weakens the upper mantle lid, facilitating lithospheric rupture of the Sierra Microplate. Similar to the LT sequence, the SV event is also associated with increased upper crustal seismicity. An 27 October 2011, Mw 4.7 earthquake occurred directly above the deep SV sequence at the base of the upper crustal seismogenic zone ( 15 km depth).

  15. Determination of hydraulic conductivities of low permeability materials in the Sierra Ladrones Formation, Albuquerque basin

    Energy Technology Data Exchange (ETDEWEB)

    Planert, C.S.

    1995-06-01

    Low permeability materials in the Sierra Ladrones Formation were sampled and analyzed to determine their hydraulic conductivities using the falling head centrifugation method (fc) as described by Nimmo et al. (1991). The method is similar to the traditional falling head method, only it uses greatly increased centrifugal forces, allowing measurements to make in a relatively short amount of time. Using these measurements, variations in saturated hydraulic conductivities between different sediment types were analyzed using Analysis of Variance (ANOVA). Sampling resulted in useable data chiefly from the clay and silt facies of the formation. The range of conductivities determined are representative of brown and red clays, and silts which make up the overbank deposits of this region. Hydraulic conductivities for these overbank fines were found to range from approximately log K = {minus}9 m/s to log K = {minus}7 m/s. The upper measurement limit of the centrifuge apparatus was determined to be approximately 1.43 {times} 10{sup {minus}7} m/s and the lower limit was approximately 7.6 {times} 10{sup {minus}12} m/s.

  16. El paisaje vegetal de la Sierra de Juan Robre y Jana (Oriente de Asturias

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    Ruiz Fernández, Jesús

    2006-06-01

    Full Text Available This paper is aimed at studying the vegetal formations found in a middle altitude ridge on Eastern Asturias. The characteristics and current distribution of these formations result from a combination of factors such as the climate, the relief, the soil and the systematic human action. Particularly relevant are the beech forests, the evergreen holm oak and the willow groves. Mixed forests of atlantic deciduous leaves species are properly represented, as well as chestnuts and oak groves. However, the most extended vegetal formations are heathers, gorses, ferns and pastures, as a consequence of traditional agricultural practices.

    Se estudian las formaciones vegetales existentes en una sierra de altitud media del oriente asturiano. Las características y la distribución actual de dichas formaciones son el resultado de la combinación de factores como el clima, el relieve, los suelos y la secular intervención humana. Por su elevado interés destacan formaciones como los hayedos, los encinares y las saucedas arbustivas. Los bosques mixtos de frondosas planocaducifolias también están bien representados, al igual que los castañedos y los robledales. No obstante las formaciones que más superficie ocupan son los brezales, los helechales, los aulagares y los pastizales, fruto de las prácticas desarrolladas al amparo del sistema de explotación agrario tradicional.

  17. Assessment of Environmental Contamination and Environmental Decontamination Practices within an Ebola Holding Unit, Freetown, Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Daniel Youkee

    Full Text Available Evidence to inform decontamination practices at Ebola holding units (EHUs and treatment centres is lacking. We conducted an audit of decontamination procedures inside Connaught Hospital EHU in Freetown, Sierra Leone, by assessing environmental swab specimens for evidence of contamination with Ebola virus by RT-PCR. Swabs were collected following discharge of Ebola Virus Disease (EVD patients before and after routine decontamination. Prior to decontamination, Ebola virus RNA was detected within a limited area at all bedside sites tested, but not at any sites distant to the bedside. Following decontamination, few areas contained detectable Ebola virus RNA. In areas beneath the bed there was evidence of transfer of Ebola virus material during cleaning. Retraining of cleaning staff reduced evidence of environmental contamination after decontamination. Current decontamination procedures appear to be effective in eradicating persistence of viral RNA. This study supports the use of viral swabs to assess Ebola viral contamination within the clinical setting. We recommend that regular refresher training of cleaning staff and audit of environmental contamination become standard practice at all Ebola care facilities during EVD outbreaks.

  18. Late Holocene Vegetation Change in the Sierra Madre Oriental of Central Mexico

    Science.gov (United States)

    Conserva, Maria Elena; Byrne, Roger

    2002-09-01

    Past vegetation and climate changes reconstructed from a sediment core from Laguna Atezca, Molango, Mexico, provide new insights into the environmental and cultural histories of the Sierra Madre Oriental during the last 1700 yr. Pollen, microscopic charcoal, sediment chemistry, loss on ignition, and magnetic susceptibility indicate that three phases of human occupation, deforestation, and erosion (ca. A.D. 280-890, ca. A.D. 1030-1420, and ca. A.D. 1680-present) alternate with two phases of abandonment (ca. A.D. 890-1030 and ca. A.D. 1420-1680). Forest composition of the two abandonment phases differed, with cloud forest taxa ( Liquidambar, Ostrya/Carpinus, Ulmus, etc.) dominating the pollen record during the first phase, and Quercus and Pinus pollen characterizing phase two. These differences may reflect a climate change in which the second phase was drier than the first; Alternatively, the increase in Pinus and Quercus may have been caused by a human-induced decline in soil fertility. The Laguna Atezca record also differs from several other Mesoamerican paleoenvironmental records in that it shows no evidence of drought at the end of the Classic Period, ca. A.D. 900.

  19. Characterizing the Networks of Digital Information that Support Collaborative Adaptive Forest Management in Sierra Nevada Forests.

    Science.gov (United States)

    Lei, Shufei; Iles, Alastair; Kelly, Maggi

    2015-07-01

    Some of the factors that can contribute to the success of collaborative adaptive management--such as social learning, open communication, and trust--are built upon a foundation of the open exchange of information about science and management between participants and the public. Despite the importance of information transparency, the use and flow of information in collaborative adaptive management has not been characterized in detail in the literature, and currently there exist opportunities to develop strategies for increasing the exchange of information, as well as to track information flow in such contexts. As digital information channels and networks have been increased over the last decade, powerful new information monitoring tools have also been evolved allowing for the complete characterization of information products through their production, transport, use, and monitoring. This study uses these tools to investigate the use of various science and management information products in a case study--the Sierra Nevada Adaptive Management Project--using a mixed method (citation analysis, web analytics, and content analysis) research approach borrowed from the information processing and management field. The results from our case study show that information technologies greatly facilitate the flow and use of digital information, leading to multiparty collaborations such as knowledge transfer and public participation in science research. We conclude with recommendations for expanding information exchange in collaborative adaptive management by taking advantage of available information technologies and networks.

  20. Landscape genetics of alpine Sierra Nevada salamanders reveal extreme population subdivision in space and time.

    Science.gov (United States)

    Savage, Wesley K; Fremier, Alexander K; Shaffer, H Bradley

    2010-08-01

    Quantifying the influence of the landscape on the genetic structure of natural populations remains an important empirical challenge, particularly for poorly studied, ecologically cryptic species. We conducted an extensive microsatellite analysis to examine the population genetics of the southern long-toed salamander (Ambystoma macrodactylum sigillatum) in a naturally complex landscape. Using spatially explicit modelling, we investigated the influence of the Sierra Nevada topography on potential dispersal corridors between sampled populations. Our results indicate very high-genetic divergence among populations, high within-deme relatedness, and little evidence of recent migration or population admixture. We also discovered unexpectedly high between-year genetic differentiation (F(ST)) for breeding sites, suggesting that breeding groups vary over localized space and time. While environmental factors associated with high-elevation montane habitats apparently play an important role in shaping population differentiation, additional, species-specific biological processes must also be operating to account for observed deviations from temporal, among-year panmixia. Our study emphasizes the population-level insights that can be gained from high-density sampling in space and time, and the highly substructured population biology that may characterize amphibians in extreme montane habitats.

  1. Can footwall unloading explain late Cenozoic uplift of the Sierra Nevada crest?

    Science.gov (United States)

    Thompson, G.A.; Parsons, T.

    2009-01-01

    Globally, normal-fault displacement bends and warps rift flanks upwards, as adjoining basins drop downwards. Perhaps the most evident manifestations are the flanks of the East African Rift, which cuts across the otherwise minimally deformed continent. Flank uplift was explained by Vening Meinesz (1950, Institut Royal Colonial Belge, Bulletin des Seances, v. 21, p. 539-552), who recognized that isostasy should cause uplift of a normal-faulted footwall and subsidence of its hanging wall. Uplift occurs because slip on a dipping normal fault creates a broader root of less-dense material beneath the footwall, and a narrowed one beneath the hanging wall. In this paper, we investigate the potential influence of this process on the latest stages of Sierra Nevada uplift. Through theoretical calculations and 3D finite element modelling, we find that cumulative slip of about 4km on range-front faults would have produced about 1.3km peak isostatic uplift at the ridge crest. Numerical models suggest that the zone of uplift is narrow, with the width controlled by bending resistance of the seismogenic crust. We conclude that footwall unloading cannot account for the entire elevation of the Sierran crest above sea level, but if range-front faulting initiated in an already elevated plateau like the adjacent Basin and Range Province, then a hybrid model of pre-existing regional uplift and localized footwall unloading can account for the older and newer uplift phases suggested by the geologic record.

  2. First horizontal well opens new gas opportunities in the Sierra Chata Field Neuquen Basin-Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, C.A.; Nilson, G.J.; Acree, J.F.; Del Pino, M.A. [Devon Energy Corp., Calgary, AB (Canada); Anaya, L. [BJ Services Co. USA, Houston, TX (United States)

    2002-07-01

    This paper described the drilling activity surrounding the first horizontal re-entry gas well in the Sierra Chata field in the Neuquen basin in Argentina. In particular, a model forecast was compared with the final results. The re-entry well was originally designed to add gas reserves and to incorporate horizontal well technology to help access the thin sands with low permeability. A numeric simulation of the 1000 m horizontal well was used to predict an initial gas flow rate of 17.7 MMscfd with an estimated final recovery of 7.3 Bscf. This forecast was confirmed following the first year of production. Operational problems, however, were encountered and new solutions were needed to bring the well back on line. The use of an existing well bore saved $1 MM and improved the economics of the project. When re-entering the existing well bore, no new flow line was needed. Given the success of this first re-entry well, it was suggested that this technology can now be used for the Machiline formation which has low productivity for several reasons, including thin sands, low permeability and difficult access via vertical wells. The use of mud logs and resistivity/gamma ray logs while drilling was very important for geological control purposes. It was noted that a measurement while drilling (MWD) tool closer to the bit would have further improved the ability to stay within very thin target zones. 11 refs., 19 figs.

  3. Seasonal biology of Ferrisia gilli (Hemiptera: Pseudococcidae) in California Sierra foothill vineyards.

    Science.gov (United States)

    Wunderlich, Lynn R; Cooper, Monica L; Daane, Kent M

    2013-08-01

    The mealybug Ferrisia gilli Gullan is an emerging pest of wine grapes grown in California's Sierra foothills. A relatively new species, it had previously been recorded as a pest of pistachio, almond, and ornamentals. It was first reported on grape in El Dorado County in 2003 and has since established and spread. Nondestructive monitoring of grape vine sections was conducted in untreated vineyard plots and compared with destructive sampling conducted in grower-treated plots in 2008 and 2009 to determine F. gilli life stage seasonal presence, number of generations, location on the vine during the season, and damage potential to fruit clusters. Two generations were observed to be completed during the season. F. gilli overwintered under the bark at the base of the trunk, trunk, and cordon as second and third instars. Adults were found at the base of emerging shoots (spring) or on and under bark of old and new spurs. Live crawlers were born in June (first generation) and late August to September (second generation), and migrated to leaves to feed before moving to protected locations under bark or into fruit clusters. Lower mealybug densities and fruit damage were recorded on vines with than without insecticide treatment(s). Parasitized mealybugs were collected in low numbers and an Acerophagus sp. was the dominant parasitoid.

  4. Variaciones texturales y movilidad geoquímica asociadas a milonitización: la zona de cizalla del granitoide El Tigre, Sierra de Pie de Palo, Sierras Pampeanas Occidentales, San Juan Textural variations and chemical mobility during mylonitization: The El Tigre granitoid shear zone, Sierra de Pie de Palo, western sierras pampeanas, San Juan

    Directory of Open Access Journals (Sweden)

    Brígida Castro De Machuca

    2010-03-01

    Full Text Available Una faja de cizalla dúctil con foliación milonítica de dirección NEE y buzamiento al sudeste, afecta a un granitoide mesoproterozoico (Granitoide El Tigre: 31º31'30''S-68º15'12''O que forma parte del basamento cristalino de la Sierra de Pie de Palo, Sierras Pampeanas Occidentales. El análisis cinemático de la faja indica una componente principal de desplazamiento de rumbo con sentido de movimiento dextral. En el granitoide no deformado (protolito se preservan asociaciones minerales y texturas relícticas, ígneas y metamórficas, que son obliteradas por la deformación. La milonitización operó en un sistema abierto provocando la movilización (ganancia o pérdida de casi todos los elementos mayores y traza, incluyendo las tierras raras e isótopos de Rb/Sr y Sm/Nd. Los cambios químicos fueron controlados mayormente por transporte sintectónico de fluidos y por transformaciones mineralógicas producidas durante la milonitización (disminución del contenido de granate, biotita y minerales accesorios y neoformación de mica blanca en la matriz de las milonitas. Las variaciones isotópicas entre el protolito y las milonitas también serían resultado de la intervención de fluidos durante la deformación, con interacción variable entre fluido y rocas de caja. Los cambios texturales, mineralógicos y químicos experimentados por el granitoide durante la milonitización, permiten reconstruir su evolución tectono-metamórfica y las condiciones metamórficas imperantes. Las asociaciones minerales y microestructuras de deformación de las milonitas sugieren para la faja de cizalla del granitoide El Tigre condiciones propias de la facies de esquistos verdes, con temperaturas inferiores a los 400 °C. Este evento deformante tuvo lugar a los 473 ± 10 Ma durante la orogenia Famatiniana.A high-strain ductile shear zone trending NEE with southeasterly dipping mylonitic foliation, has been recognized affecting a Mesoproterozoic (ca. 1105 Ma

  5. Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain

    Science.gov (United States)

    Martínez, I.; Rosa, M.; Arsuaga, J.-L.; Jarabo, P.; Quam, R.; Lorenzo, C.; Gracia, A.; Carretero, J.-M.; de Castro, J.-M. Bermúdez; Carbonell, E.

    2004-01-01

    Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range. PMID:15213327

  6. Short Report: Serological Evidence of Under-Reported Dengue Circulation in Sierra Leone.

    Science.gov (United States)

    de Araújo Lobo, Jaime M; Mores, Christopher N; Bausch, Daniel G; Christofferson, Rebecca C

    2016-04-01

    Dengue virus (DENV) is thought to have emerged from a sylvatic cycle in Africa but has since become adapted to an urban-centric transmission cycle. These urban areas include villages in West Africa where DENV is not often routinely considered for patients presenting with febrile illnesses, as other endemic diseases (malaria, Lassa fever, e.g.) present with similar non-specific symptoms. Thus, dengue is likely under diagnosed in the region. These plaque reduction neutralization test-50 (PRNT50) screening results of patients presenting with fevers of unknown origin (FUO) at a clinic in Kenema, Sierra Leone indicate that all four serotypes of DENV likely circulate in areas surrounding Kenema. Using a more conservative PRNT80 cut-off value, our results still indicate the presence of antibody to all four serotypes in the region. Identifying alternate etiologies of FUOs in this region will assist clinicians in plan-of-care decisions as well as follow-up priorities. This is particularly relevant given the Ebola outbreak in the region, where diagnosis has a range of downstream effects ranging from correct allocation of medical resources, appropriate isolation of patients, and ultimately, a better informed public health sector.

  7. Short Report: Serological Evidence of Under-Reported Dengue Circulation in Sierra Leone

    Science.gov (United States)

    de Araújo Lobo, Jaime M.; Mores, Christopher N.; Bausch, Daniel G.

    2016-01-01

    Dengue virus (DENV) is thought to have emerged from a sylvatic cycle in Africa but has since become adapted to an urban-centric transmission cycle. These urban areas include villages in West Africa where DENV is not often routinely considered for patients presenting with febrile illnesses, as other endemic diseases (malaria, Lassa fever, e.g.) present with similar non-specific symptoms. Thus, dengue is likely under diagnosed in the region. These plaque reduction neutralization test-50 (PRNT50) screening results of patients presenting with fevers of unknown origin (FUO) at a clinic in Kenema, Sierra Leone indicate that all four serotypes of DENV likely circulate in areas surrounding Kenema. Using a more conservative PRNT80 cut-off value, our results still indicate the presence of antibody to all four serotypes in the region. Identifying alternate etiologies of FUOs in this region will assist clinicians in plan-of-care decisions as well as follow-up priorities. This is particularly relevant given the Ebola outbreak in the region, where diagnosis has a range of downstream effects ranging from correct allocation of medical resources, appropriate isolation of patients, and ultimately, a better informed public health sector. PMID:27116605

  8. The etiology of Ebola virus disease-like illnesses in Ebola virusnegative patients from Sierra Leone

    Science.gov (United States)

    Li, Lei; Ji, Dong; Ji, Ying-Jie; Li, Chen; Gao, Xu-Dong; Wang, Li-Fu; Zhao, Min; Duan, Xue-Zhang; Duan, Hui-Juan

    2016-01-01

    During the 2014 Ebola virus disease (EVD) outbreak, less than half of EVD-suspected cases were laboratory tested as Ebola virus (EBOV)-negative, but disease identity remained unknown. In this study we investigated the etiology of EVD-like illnesses in EBOV-negative cases. From November 13, 2014 to March 16, 2015, EVD-suspected patients were admitted to Jui Government Hospital and assessed for EBOV infection by real-time PCR. Of 278 EBOV negative patients, 223 (80.21%), 142 (51.08%), 123 (44.24%), 114 (41.01%), 59 (21.22%), 35 (12.59%), and 12 (4.32%) reported fever, headache, joint pain, fatigue, nausea/vomiting, diarrhea, hemorrhage, respectively. Furthermore, 121 (43.52%), 44 (15.83%), 36 (12.95%), 33 (11.87%), 23 (8.27%), 10 (3.60%) patients were diagnosed as infection with malaria, HIV, Lassa fever, tuberculosis, yellow fever, and pneumonia, respectively. No significant differences in clinical features and symptoms were found between non-EVD and EVD patients. To the best of our knowledge, the present study is the first to explore the etiology of EVD-like illnesses in uninfected patients in Sierra Leone, highlighting the importance of accurate diagnosis to EVD confirmation. PMID:27058894

  9. [Mammals' camera-trapping in Sierra Nanchititla, Mexico: relative abundance and activity patterns].

    Science.gov (United States)

    Monroy-Vilchis, Octavio; Zarco-González, Martha M; Rodríguez-Soto, Clarita; Soria-Díaz, Leroy; Urios, Vicente

    2011-03-01

    Species conservation and their management depend on the availability of their population behavior and changes in time. This way, population studies include aspects such as species abundance and activity pattern, among others, with the advantage that nowadays new technologies can be applied, in addition to common methods. In this study, we used camera-traps to obtain the index of relative abundance and to establish activity pattern of medium and large mammals in Sierra Nanchititla, Mexico. The study was conducted from December 2003 to May 2006, with a total sampling effort of 4 305 trap-days. We obtained 897 photographs of 19 different species. Nasua narica, Sylvilagus floridanus and Urocyon cinereoargenteus were the most abundant, in agreement with the relative abundance index (RAI, number of independent records/100 trap-days), and according to previous studies with indirect methods in the area. The activity patterns of the species showed that 67% of them are nocturnal, except Odocoileus virginianus, Nasua narica and others. Some species showed differences with previously reported patterns, which are related with seasonality, resources availability, organism sex, principally. The applied method contributed with reliable data about relative abundance and activity patterns.

  10. Short Report: Serological Evidence of Under-Reported Dengue Circulation in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Jaime M de Araújo Lobo

    2016-04-01

    Full Text Available Dengue virus (DENV is thought to have emerged from a sylvatic cycle in Africa but has since become adapted to an urban-centric transmission cycle. These urban areas include villages in West Africa where DENV is not often routinely considered for patients presenting with febrile illnesses, as other endemic diseases (malaria, Lassa fever, e.g. present with similar non-specific symptoms. Thus, dengue is likely under diagnosed in the region. These plaque reduction neutralization test-50 (PRNT50 screening results of patients presenting with fevers of unknown origin (FUO at a clinic in Kenema, Sierra Leone indicate that all four serotypes of DENV likely circulate in areas surrounding Kenema. Using a more conservative PRNT80 cut-off value, our results still indicate the presence of antibody to all four serotypes in the region. Identifying alternate etiologies of FUOs in this region will assist clinicians in plan-of-care decisions as well as follow-up priorities. This is particularly relevant given the Ebola outbreak in the region, where diagnosis has a range of downstream effects ranging from correct allocation of medical resources, appropriate isolation of patients, and ultimately, a better informed public health sector.

  11. Origin of Meter-Size Granite Basins in the Southern Sierra Nevada, California

    Science.gov (United States)

    Moore, James G.; Gorden, Mary A.; Robinson, Joel E.; Moring, Barry C.

    2008-01-01

    Meter-size granite basins are found in a 180-km belt extending south from the South Fork of the Kings River to Lake Isabella on the west slope of the southern Sierra Nevada, California. Their origin has long been debated. A total of 1,033 basins have been inventoried at 221 sites. The basins occur on bedrock granitic outcrops at a median elevation of 1,950 m. Median basin diameter among 30 of the basin sites varies from 89 to 170 cm, median depth is 12 to 63 cm. Eighty percent of the basin sites also contain smaller bedrock mortars (~1-2 liters in capacity) of the type used by Native Americans (American Indians) to grind acorns. Features that suggest a manmade origin for the basins are: restricted size, shape, and elevation range; common association with Indian middens and grinding mortars; a south- and west-facing aspect; presence of differing shapes in distinct localities; and location in a food-rich belt with pleasant summer weather. Volcanic ash (erupted A.D. 1240+-60) in the bottom of several of the basins indicates that they were used shortly before ~760 years ago but not thereafter. Experiments suggest that campfires built on the granite will weaken the bedrock and expedite excavation of the basins. The primary use of the basins was apparently in preparing food, including acorns and pine nuts. The basins are among the largest and most permanent artifacts remaining from the California Indian civilization.

  12. Helminth infections in British troops following an operation in Sierra Leone.

    Science.gov (United States)

    Bailey, M S; Thomas, R; Green, A D; Bailey, J W; Beeching, N J

    2006-09-01

    One hundred and fifty-three British soldiers and 86 Royal Air Force (RAF) personnel were deployed on a hostage rescue operation in Sierra Leone. For 3 days they were exposed to various infection risks and 6 weeks later some of the soldiers presented with gastrointestinal complaints. Both groups were screened with structured questionnaires, blood investigations and (where indicated) faecal microscopy and charcoal culture for helminths. Definite and probable cases of helminth infection were treated with albendazole and all soldiers were screened again after 3 months. Among the soldiers investigated, 73/145 (50%) reported gastrointestinal symptoms and 70/139 (50%) had eosinophilia. Among these, 17/66 (26%) had hookworm infection, 6/66 (9%) had Strongyloides stercoralis infection and 1/66 (2%) had Giardia lamblia infection. Eosinophilia was most strongly associated with entering the enemy camp and being in the platoon that attacked the area around the camp latrines. Among RAF personnel, who were not involved in activities on the ground, 3/86 (3%) had borderline eosinophilia. Treatment of 105/153 (69%) soldiers with albendazole was well tolerated and, on follow-up screening 3 months later, 23/124 soldiers (19%) had gastrointestinal symptoms and 18/121 (15%) had eosinophilia. Faecal investigations and schistosomiasis serology tests were all negative at this stage.

  13. TAXONOMIC COMPOSITION AND ECOLOGICAL DATA OF THE LYCOPHYTES AND MONILOPHYTES FROM SIERRA DE TAMAULIPAS, TAMAULIPAS, MEXICO

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    Ana María Hernández-Mendoza

    2015-11-01

    Full Text Available En el presente estudio se enlistan las licofitas y monilofitas que habitan en la sierra de Tamaulipas, registrándose un total de 18 familias, 38 géneros, 91 especies y ocho variedades. La familia Pteridaceae es la más representativa tanto en géneros (13 como en especies (36, siendo el género Cheilanthes el más sobresaliente, además se registran por primera vez 23 taxones para el estado de Tamaulipas. Se recolectó una especie que se consideraba había desaparecido de la zona como es el caso de Schaffneria nigripes Fée, que desde hace 30 años no se había vuelto a encontrar. El único taxón endémico para el estado fue Notholaena brevistipes Mickel. Los ejemplares que se mencionan en el trabajo como Anemia sp., Elaphoglossum sp. y Selaginella hansenii Hieron. vel. aff., Cheilanthes eatonii Baker vel. aff. y Ch. lozanoi (Maxon R.M. Tryon & A.F. Tryon podrían tratarse de nuevas especies. En este trabajo se incluye la distribución de las especies por tipos de vegetación, microhábitats y algunos datos ecológicos. Se identificaron cinco tipos de vegetación y tres asociaciones vegetales en el área de estudio.

  14. Problems behind Education for All (EFA: The Case of Sierra Leone

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    Mikako Nishimuko

    2007-12-01

    Full Text Available This paper discusses Sierra Leone’s commitment to EFA and the possibility of unintended consequences if its success is measured only by results showing quantitative gains while downplaying the decline in the quality of the education offered. Equal access to quality education is an integral part of EFA. With donors’ assistance, the government has made a strong commitment to achieve the international goal of EFA. A free primary education policy introduced in 2000 has led to rapid progress in terms of access to schooling. However, fieldwork research based on observation of schools, interviews with teachers, and questionnaires from pupils, parents and teachers in 27 schools in five towns, shows that the quality of the education provided has been compromised due to the rapid increase in the number of enrolled children; a high teacher-pupil ratio, a shortage of teaching and learning materials, school buildings and furniture, and low motivation on the part of teachers are quite common. This paper also argues for the role of Non-Governmental Organisations (NGOs in supplementing government efforts to expand educational access of acceptable quality, especially when the government’s capacity to deliver education is weak.

  15. Assessment of Environmental Contamination and Environmental Decontamination Practices within an Ebola Holding Unit, Freetown, Sierra Leone.

    Science.gov (United States)

    Youkee, Daniel; Brown, Colin S; Lilburn, Paul; Shetty, Nandini; Brooks, Tim; Simpson, Andrew; Bentley, Neil; Lado, Marta; Kamara, Thaim B; Walker, Naomi F; Johnson, Oliver

    2015-01-01

    Evidence to inform decontamination practices at Ebola holding units (EHUs) and treatment centres is lacking. We conducted an audit of decontamination procedures inside Connaught Hospital EHU in Freetown, Sierra Leone, by assessing environmental swab specimens for evidence of contamination with Ebola virus by RT-PCR. Swabs were collected following discharge of Ebola Virus Disease (EVD) patients before and after routine decontamination. Prior to decontamination, Ebola virus RNA was detected within a limited area at all bedside sites tested, but not at any sites distant to the bedside. Following decontamination, few areas contained detectable Ebola virus RNA. In areas beneath the bed there was evidence of transfer of Ebola virus material during cleaning. Retraining of cleaning staff reduced evidence of environmental contamination after decontamination. Current decontamination procedures appear to be effective in eradicating persistence of viral RNA. This study supports the use of viral swabs to assess Ebola viral contamination within the clinical setting. We recommend that regular refresher training of cleaning staff and audit of environmental contamination become standard practice at all Ebola care facilities during EVD outbreaks.

  16. Timing and new geomorphologic evidence of the last deglaciation stages in Sierra Nevada (southern Spain)

    Science.gov (United States)

    Palacios, David; Gómez-Ortiz, Antonio; Andrés, Nuria; Salvador, Ferrán; Oliva, Marc

    2016-10-01

    The main objective of this research is to improve knowledge of the deglaciation stages in Sierra Nevada (southern Spain) by applying 36Cl cosmogenic exposure dating to 28 samples from moraine and fossil rock glacier boulders and glacial polished surfaces, in 5 glaciated valleys around Veleta Peak (3396 m asl; 37°03‧02″N 3°20‧54″W). The results show that shortly before the Last Glacial Maximum (LGM) and during the LGM, the heads of the glacial valleys were occupied by ice tongues, with possible glacial transfluence between the valleys. After 19 ka, a major glacial regression started, but glaciers during the Oldest Dryas (OD) expanded again and refilled the valley bottoms. The glacial advances of the pre-LGM, LGM and OD formed polygenic moraine systems. During the Bølling-Allerød the glaciers receded and probably disappeared. Thereafter, the valley bottoms remained ice-free. During the Younger Dryas (YD) small glaciers developed again, but only in cirques shaped on east-facing slopes. Subsequently, these glaciers started retreating towards their valley heads and finally disappeared completely. With the onset of the Holocene, rock glaciers developed inside the deglaciated cirques on the eastern slopes of some valleys, but only under the most active and protected headwalls did large complex rock glaciers develop and remained active until the mid-Holocene.

  17. Descubrimiento de pinturas rupestres en la Sierra de la Culebra (Zamora

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    Ramón GRANDE DEL BRÍO

    2009-10-01

    Full Text Available En el mes de enero de 1977, un recorrido de prospección arqueológica me llevó hasta Linarejos, aldea situada cabe la falda oriental de la sierra de la Culebra, al noroeste de la provincia de Zamora. Tomé desde allí el antiguo camino que conducía a Villarino de Manzanas, hacia el sur. Un grupo de canchales de naturaleza cuarcítica con orientación noroeste-sureste (armoricana se extendían cabe el paso del Portillón. El reconocimiento por mi parte de varios covachos que se abrían en la canchalera en cuestión me permitió descubrir pinturas rupestres de tipo esquemático en uno de ellos. Las pinturas se presentan distribuidas en un panel interior del covacho, a una altura de un metro setenta centímetros respecto del suelo. Están pintadas en color rojo. Ligeramente desvaídas.

  18. Evidencias del ciclo Pampeano en el basamento del sector noroccidental de la sierra de San Luis

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    GI Vujovich

    2003-12-01

    Full Text Available Se presenta una edad preliminar U-Pb sobre circones de un gneis biotítico feldespático perteneciente al Complejo Nogolí aflorante en las cercanías de San Francisco del Monte de Oro, sierra de San Luis. Los resultados indican una edad de cristalización para el mismo de 554 ± 4,8 Ma, representando un interesante hallazgo del ciclo Pampeano en el marco geológico considerado. Se postula además la existencia de un proceso de pérdida episódica de Pb durante el Cretácico inferior (112 ± 23 Ma, reflejado en la intersección inferior de la recta de discordia. Esta edad inferior podría asociarse con gradientes térmicos anómalos relacionados con los procesos distensivos generalizados que afectaron al Gondwana durante la apertura del océano Atlántico Sur.

  19. Assessment of Community Event–Based Surveillance for Ebola Virus Disease, Sierra Leone, 2015

    Science.gov (United States)

    Crowe, Samuel J.; Jasperse, Joseph; Privette, Grayson; Stone, Erin; Miller, Laura; Hertz, Darren; Fu, Clementine; Maenner, Matthew J.; Jambai, Amara; Morgan, Oliver

    2016-01-01

    In 2015, community event–based surveillance (CEBS) was implemented in Sierra Leone to assist with the detection of Ebola virus disease (EVD) cases. We assessed the sensitivity of CEBS for finding EVD cases during a 7-month period, and in a 6-week subanalysis, we assessed the timeliness of reporting cases with no known epidemiologic links at time of detection. Of the 12,126 CEBS reports, 287 (2%) met the suspected case definition, and 16 were confirmed positive. CEBS detected 30% (16/53) of the EVD cases identified during the study period. During the subanalysis, CEBS staff identified 4 of 6 cases with no epidemiologic links. These CEBS-detected cases were identified more rapidly than those detected by the national surveillance system; however, too few cases were detected to determine system timeliness. Although CEBS detected EVD cases, it largely generated false alerts. Future versions of community-based surveillance could improve case detection through increased staff training and community engagement. PMID:27434608

  20. A transient fault-valve mechanism operating in upper crustal level, Sierras Pampeanas, Argentina

    Science.gov (United States)

    Japas, María Silvia; Urbina, Nilda Esther; Sruoga, Patricia; Garro, José Matías; Ibañes, Oscar

    2016-11-01

    Located in the Sierras Pampeanas (the broken-foreland of the Pampean flat slab segment in the southern Central Andes), the Cerro Tiporco volcanic field shows Neogene hydrothermal activity linked to migration of arc-magmatism into the foreland. Late Neogene deposits comprise epithermal vein systems emplaced in Precambrian-Early Palaeozoic igneous-metamorphic basement, Late Miocene sedimentary rocks and Early Pliocene volcaniclastic rocks. Mineralization consists of calcareous onyx, aragonite and calcite veins as well as travertine deposits. Onyx and aragonite occur as fill of low-displacement nearly vertical reverse-sinistral faults striking NW, and nearly horizontal dilatant fractures. The latter consist of load-removal induced fractures affecting the igneous-metamorphic rocks, as well as bedding planes in the Late Miocene sediments. The presence of veins recording multiple fracture episodes and crack-and-seal growth of veins suggests relatively low differential stress and supralithostatic fluid pressure, as well as cyclic changes in pore pressure and high mineral-deposition/fracture-opening ratio. These conditions support a mechanism of fault-valve behaviour during onyx and aragonite vein emplacement. The fault-valve mechanism involves fractures associated with impermeable barriers between environments with different fluid pressure. Faulting generated an appreciable directional permeability triggering fluid migration from the highest to the lowest pressure region, with subsequent deposition and sealing that started a new pressurization-faulting-sealing cycle. Late aragonite and calcite veins suggest a change in kinematics indicating the onset of tectonic-load conditions.

  1. Secciones estructurales de Las Sierras Australes de la provincia de Buenos Aires: Repetición de la secuencia estratigráfica a partir de fallas inversas?

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    Renata N. Tomezzoli

    2004-06-01

    Full Text Available Las Sierras Australes o Sierras de la Ventana están ubicadas en el sudoeste de la provincia de Buenos Aires, entre los 37°-39°S y los 61°- 63°O y constituyen una faja plegada y corrida con rumbo general noroeste. Están formadas por rocas de edades precámbricas a pérmicas. Las sierras más viejas e intensamente deformadas son las occidentales mientras que las más jóvenes y menos deformadas se ubican hacia el este. En este trabajo se presentan dos secciones regionales desde la localidad de López Lecube hasta el arroyo Quiñihual y en el abra de Agua Blanca - Hinojo, que corroboran la importancia del fallamiento en el desarrollo de las sierras. El contacto principal entre los Grupos Curamalal y Ventana se interpreta aqui como un corrimiento que repite la secuencia. Se presenta una seccion esquemática de las sierras siguiendo esta idea.

  2. Fauna del suelo en bosques y cafetales de la Sierra Nevada de Santa Marta, Colombia Soil fauna in forest and coffee plantations from the Sierra Nevada de Santa Marta, Colombia

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    Camero R. Edgar

    2002-11-01

    Full Text Available

    En la Sierra Nevada de Santa Marta se establecieron dos estaciones de muestreo en las localidades de Minca a 700 m de altitud y María Teresa a 790 m, para realizar comparaciones de la fauna asociada a los suelos de plantaciones de café y de bosques naturales. Las colecciones se realizaron tanto en la hojarasca como en los horizontes  subsuperficiales O, Ay B de las dos coberturas vegetales mediante el empleo de trampas Pitfall y Berlesse y se utilizaron índices de diversidad, abundancia relativa y frecuencia para comparar su composici6n biológica, la cual se determine a nivel de familia. Los resultados mostraron diferencias significativas, tanto en la composición como en la abundancia y frecuencia de los grupos colectados en los dos tipos de ecosistemas, así Como variaciones altitudinales significativas al comparar los resultados obtenidos en los bosques nativos con trabajos hechos en zonas de mayor altitud en este sistema montañoso.

    Two research stations (Minca, 700 m altitude and Marfa Teresa, 790 m altitude were established in the Sierra Nevada de Santa Marta in places to study the soil fauna associated with forest and coffee plantations. Soil fauna was collected using Pitfall and Berlesse traps. Samples were taken from litter as well as from horizons O, A and B. Individuals collected were identified to family level. Diversity, abundance and frequency indexes were used to compare fauna composition at both sites. Significant differences were found between the two research sites as well as with data from other high altitude forest in the Sierra Nevada de Santa Marta.

  3. Recent large fold nucleation in the upper crust: Insight from gravity, magnetic, magnetotelluric and seismicity data (Sierra de Los Filabres-Sierra de Las Estancias, Internal Zones, Betic Cordillera)

    Science.gov (United States)

    Pedrera, Antonio; Galindo-Zaldívar, Jesús; Ruíz-Constán, Ana; Duque, Carlos; Marín-Lechado, Carlos; Serrano, Inmaculada

    2009-01-01

    Rheological heterogeneities in the upper-crust have a close relationship with the fold position where rigid bodies could constitute initial perturbations that allow the nucleation of folds. Consequently, establish the position and geometry of anomalous rocks located in the upper-crust by geophysical studies help to understand the folded structure observed on surface. New geological observations in the field, along with gravity, magnetic, magnetotelluric and seismicity data, reveal the subsurface structure in the Sierra de Los Filabres-Sierra de Las Estancias folded region part of the Alpine belt in southern Spain. The geometry of the upper crust is determined by geological field data, 2D gravity models, 2D magnetic models and 2D MT resistivity model, while seismicity evidences the location of the deep active structures. These results allow us to propose that a basic rock body at 4 to 9 km depth has determined the nucleation and development of the Sierra de Los Filabres kilometric antiform. N-vergent large late folds are subjected to a variable present-day stress field. Earthquake focal mechanisms suggest the presence in depth of a regional NW-SE compressive stress field. However, most of the seismogenetic structures do not extend up to the surface, where NW-SE and WNW-ESE outcropping active normal faults are observed, thus indicating a NE-SW extension in the upper crust simultaneous to orthogonal NW-SE compression related to reverse faults and minor folds developed in the Eastern Almanzora Corridor and in the nearby Huércal-Overa Basin. The recent and active tectonic studies of cordilleras hinterland subjected to late folding greatly benefits from the integration of surface observations together with geophysical data.

  4. Influencia de la tectónica preandina sobre la tectónica andina: el caso de la falla de Sierra Chica, Sierras Pampeanas de Córdoba

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    Roberto D Martino

    2012-06-01

    Full Text Available La falla de la Sierra Chica es una de las fallas inversas terciarias más importantes de las Sierras Pampeanas de Córdoba. La deformación frágil andina habría sido controlada parcialmente por estructuras previas como la foliación regional del basamento metamórfico proterozoico tardío-cámbrico. Otro control importante está dado por la tectónica extensional cretácica que produjo la apertura del océano Atlántico. La traza actual de la falla presenta tramos rectos, de alto ángulo (~50-60° y vinculados con depósitos cretácicos, que son interpretados como resultado de la reactivación de fallas directas previas, y tramos curvos de bajo ángulo (~30°, que no se asocian a ningún depósito en particular, que serían nuevas fallas inversas originadas por la tectónica terciaria. Una serie de fajas miloníticas antiguas, oblicuas al rumbo general, denominadas lineamientos Carapé, Quebrada Honda y Soconcho, producen la segmentación general de la falla de la Sierra Chica en tres grandes láminas de corrimiento. Durante la compresión terciaria, dichos lineamientos fueron reactivados como fallas de deslizamiento de rumbo dextral, que actuaron como rampas laterales mientras las láminas de corrimiento se desplazaban en sentido NNO (~N 330°. La forma convexa hacia el oeste se debería al efecto del fallamiento inverso de bajo ángulo asociado a la expansión de la parte frontal de la lámina de corrimiento. Las diferencias geobarométricas actuales (~5000 m entre los bloques exhumados a ambos lados de la falla de la Sierra Chica, a la latitud de Alta Gracia (31º 36' S, todavía reflejarían los efectos de la tectónica extensional cretácica, no compensados por la inversión terciaria.

  5. Caracterización de sitios de percha del guajolote silvestre (Meleagris gallopavo mexicana) en Sierra Fría, Aguascalientes, México Roost sites characteristics of wild turkey (Meleagris gallopavo mexicana) in Sierra Fria, Aguascalientes, Mexico

    OpenAIRE

    Marcelo Márquez-Olivas; Edmundo García-Moya; Carlos González-Rebeles Islas; Humberto Vaquera-Huerta

    2007-01-01

    Entre octubre y noviembre del año 2001 y mayo de 2002 se localizaron 16 sitios de percha de guajolote silvestre (Meleagris gallopavo mexicana) en la Sierra Fría de Aguascalientes. El 87.5% de los sitios se encontraron en bosques de pino-encino (en rodales de pinos), en altitudes de 2500 a 2650 m. En la parte alta (2/3) de la cuesta se localizaron 8 de los sitios y 7 sobre laderas de exposición noreste, en una pendiente promedio de 38.9 ± 12.6%. El 62.5% de los sitios se usaron durante todo el...

  6. Contamination of soil by heavy metals in the mining Sierra of Cartegena La Union and its environment (Southeast Spain); Contaminacion de suelos por metales pesados en la sierra minera de Cartagena La Union y su entorno (Sureste de Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Belmonte Serrato, F.; Rojo Lopez, S.; Romero Diaz, A.; Moreno Brotons, J.; Alonso Sarria, F.

    2009-07-01

    This paper analyzes the metal pollution in natural, agricultural and mineral-industrial soils in the Sierra of Cartagena La Union and its adjacent area. The analysis was conducted on 52 soil samples randomly selected and 23 samples form the bed of the channels draining to the Mar Menor and the Mediterranean sea. The results indicate high concentrations of metals that exceed, in many cases, the maximum allowable by the relevant laws of various countries, including Spain. Of note is the excessive contamination by lead (Pb) and Cinz (Zn) that doubles or even triples the maximum of the most permissive laws. (Author) 9 refs.

  7. Las superficies de erosión en las Sierras Pampeanas de Córdoba: algunas consideraciones sobre su génesis

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    C.A. Beltramone

    2007-09-01

    Full Text Available Las Sierras Pampeanas de Córdoba constituyen parte de la unidad morfoestructural Sierras Pampeanas Orientales. Se considera la existencia de una sola superficie de erosión, preservada en diferentes posiciones topográficas. Escarpas de fallas limitan las superficies de erosión reconocidas. No fueron reconocidos signos que evidencien el proceso de pedimentación en su base, ni profundos perfiles de meteorización (saprolito. Se consideran a esta superficie como una peneplanicie formada durante el Paleozoico y posteriormente desmembrada por los movimientos tectónicos que dieron lugar a la formación de las sierras de Córdoba.

  8. Tectonic evolution of the Sierra Maestra Mountains, SE Cuba, during Tertiary times: From arc-continent collision to transform motion

    Science.gov (United States)

    Rojas-Agramonte, Y.; Neubauer, F.; Garcia-Delgado, D. E.; Handler, R.; Friedl, G.; Delgado-Damas, R.

    2008-09-01

    A structural study was carried out along the southern Sierra Maestra mountain range, SE Cuba. This was aimed to monitor the effects of Paleogene island arc formation and collision due to convergence of the Caribbean and North American plates and subsequent Neogene disruption of the arc by initiation of the North Caribbean Transform Fault. In the Sierra Maestra two different and unrelated volcanic arcs are exposed, one of Cretaceous age (pre-Maastrichtian) and the other of Paleogene age, the latter forming the main expression of the mountain range. The volcanic arcs are overlain by Middle-Upper Eocene siliciclastic, carbonate and terrigenous rocks. Six distinct phases of deformation were recognized in this area (D1-D6). The first phase (D1) is related to the intrusion of a set of extensive subparallel, N-trending subvertical basalt-andesite dikes which record mainly E-W extension and N-S shortening during the Late Paleocene to Middle Eocene. The final stage of collision of eastern Cuba (Caribbean plate) with the Bahamas Platform (North American plate) began in the Middle Eocene and coincided with cessation of magmatism in the Sierra Maestra. Following uplift in the Sierra Maestra, coarse clastic sediments were deposited along the northern edge with clast provenance from the uplifted, southerly located, areas. Between Late Middle Eocene and Early Oligocene, rocks of the Sierra Maestra were deformed by nearly east-west trending folds and north-vergent thrust faults (D2) in an overall antiformal structure. This deformation was linked to a shift in the stress regime of the Caribbean plate from mainly N-S to NE-SW compression. Subsequent shifting in plate motion caused the abandonment of the Nipe-Guacanayabo fault system in the Early Oligocene and initiation of a deformation front to the south where the Oriente fault is now located. Shortening structures within the Sierra Maestra were overprinted in the Oligocene to Early Miocene by widespread extensional structures (D3

  9. Sulphide and sulphosalt mineralogy and paragenesis from the Sierra Almagrera veins, Betic Cordillera (SE Spain

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    Martínez Frías, J.

    1991-12-01

    Full Text Available The Sierra Almagrera vein-type mineralization contains base metal sulphides and Pb-Sb- Cu-Ag sulphosalts. The sulphides possess significant proportions of Ag, Sb (galena, Fe (sphalerite and Sb, Zn (chalcopyrite. Ore microscopy and electron microprobe have revealed a mineralogical and textural variation and confirmed the presence of bournonite, boulangerite and anomalous tetrahedrite. The average sulphosalt formulas are bournonite Cu0.98 Pb0. 96 Sb0.98 S3.04, boulangerite Pb4.8Sb3.8S11.34 and anomalous tetrahedrite Ag0.6Cu9.7 Zn3.6 Fe0. 44 Sb3.47 S13- The sequence of mineral deposition indicates the existance of four mineralizing stages and one supergene alteration: 1 Fe-(As; 2 Zn-Cu-Fe; 3 Pb-Sb-Cu-Ag; 4 Cu-Zn-Fe, and 5 carbonates, sulphates and supergene oxides. In broad terms, it is possible to establish the following conclusions: a there exist a mineralogical and textural variation with depth, the Pb-Sb-Cu-Ag stage reaching the maximum development; b a temperature decrease during the formation of sph. 1, linked to the progressive increase in Fe-content of the sphalerite has been detected; c the compositional homogeneity of the bournonite (and the fair lack of As in the tetrahedrite could indicate the existance of a possible tendancy to individually crystallise the Sb and As sulphosalts, according to the trend Bi → Sb → As.La mineralización filoniana de Sierra Almagrera presenta una interesante paragénesis caracterizada por la presencia de sulfuros de metales base y sulfosales de Pb-Sb-Cu-Ag. Se ha identificado una secuencialidad textural y química de las distintas fases minerales, según la cual los sulfuros poseen variaciones significativas de las proporciones de Ag, Sb (galena, Fe (esfalerita, y Sb, Zn (calcopirita, yen la que las sulfosales son fundamentalmente sulfoantimoniuros (bournonita: Cu0.98 Pb0. 96 Sb0.98 S3.04, boulangerita Pb4.8Sb3.8S11.34 y tetraedrita anómala Ag0.6Cu9.7 Zn3.6 Fe0. 44 Sb3.47 S13-. La secuencia de

  10. La fauna del pleistoceno inferior de la Sierra de Quibas (Abanilla, Murcia

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    Szyndlar, Z.

    1999-08-01

    Full Text Available The Quaternary karstic site of Sierra de Quibas (Abanilla, Murcia, Spain has provided a wide faunistic list with 53 species distributed among gastropods, myriapods, amphibians, reptiles, birds and mammals. Especially interesting among the gastropods is Palaeoglandina that became extinct in Europe during the Pliocene. It remains as a relict genus in the Pleistocene of the Iberian Peninsula. Two of the birds, Gypaetus barbatus and Geronticus eremita, and a snake, Elaphe cf. E. sealaris, are scarcely represented in the fossil record. For several birds, it is the first record in the Lower Pleistocene of the Iberian Peninsula. Among the mammals, the presence of the Cercopithecine Macaca sylvanus is especially relevant one. The assemblage of the taxa Arvicola deucalion, Castillomys rivas rivas, Eliomys intermedius, Equus altidens and Capra sp. aff. C. alba allows the correlation with Plines 1, Orce 3 and Venta Micena, among other sites. Therefore Quibas can be dated before the end of Lower Pleistocene, between 1.3 and 1 Ma. A dry paleoclimatic regime, very similar to the current climate in the geographical area, though perhaps slightly wetter and warmer, can be inferred from the faunistic assemblage. The environment of the karstic cavity was a rocky place with open brushwood areas, but in the proximities there were wetlands and woodlands, as can be inferred from the presence of birds and micromammals characteristic of these habitats.El yacimiento kárstico cuaternario de la Sierra de Quibas (Abanilla, Murcia ha proporcionado una amplia lista faunística constituida por 53 especies repartidas entre gasterópodos, miriápodos, anfibios, reptiles, aves y mamíferos. En el conjunto de los gasterópodos destaca Palaeoglandina, un género que se extingue en el resto de Europa durante el Plioceno y que se mantiene como relicto en el Pleistoceno de la Península Ibérica. Dos de las especies de aves determinadas, Gypaetus barbatus y Gerontieus eremita, y una

  11. Near-roof structure and crack-seal emplacement, Colosseum pluton, Sierra Nevada, California

    Science.gov (United States)

    Bartley, J. M.; Glazner, A. F.; Coleman, D. S.

    2011-12-01

    Field evidence from diverse localities indicates that dike-like granitic plutons are emplaced by magmatic crack-seal, yielding plutons that are essentially huge composite dikes. Plutons that are equant in map view may also form by crack-seal from increments that are subhorizontal and vertically stacked, but field evidence to assess this hypothesis is scarce. Here we present evidence that the Late Cretaceous, granitic Colosseum pluton of Moore (1963), which crops out along the Sierra Nevada crest southwest of Big Pine, California, may have been emplaced as horizontal sheets by crack-seal. The equant outcrop pattern of the elliptical, 2x3 km Colosseum pluton as mapped by Moore (1963) mainly reflects Pleistocene glacial erosion that cut ~600 m down through the pluton's gently sloping roof contact. Moore mapped a steep eastern contact with the Spook pluton, but our field observations suggest that the Spook and Colosseum plutons may be the same. This would imply that the pluton is much larger and that the map pattern is not elliptical. Additionally, the exposed intrusive contact everywhere dips gently, but the eastern intrusive contact has been cut off by the Sierran frontal fault. If so, up to 2.5 km of largely unexplored vertical relief in the pluton is exposed on the eastern escarpment of the Sierra Nevada. Geologic and bulk magnetic susceptibility mapping of near-roof rocks revealed the following. (1) Although the intrusive contact sharply truncates wall-rock foliation, xenoliths are absent, even at contacts, indicating that stoping was an insignificant process. (2) The pluton contains a subhorizontal sheet of leucogranite that is broadly concordant with the roof but bounded both above and below by more typical biotite granodiorite. This sheet may represent one or more intrusive increments. (3) Along the western contact, thin tabular apophyses of the pluton intrude its subvertically layered and foliated roof. Although some of these dip steeply and are concordant

  12. Plutón La Costa, una expresión de magmatismo tipo-s en el sector noreste de la Sierra de Velasco, Sierras Pampeanas La Costa pluton, an expresion of S- type magmatism in the northeastern sector of the Sierra de Velasco, Sierras Pampeanas

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    P.H. Alasino

    2006-06-01

    Full Text Available Estudios combinados de petrología, química mineral y geoquímcia de roca total revelan la presencia de dos unidades graníticas peraluminosas con minerales aluminosos magmáticos tales como granate y mica blanca y la presencia distintiva de turmalina. Las evidencias aquí presentadas indican que estas dos facies, Anillaco y Anjullón, junto a la unidad peraluminosa Santa Cruz estudiada en trabajos previos, constituyen una serie de rocas co-sanguíneas, emplazadas en niveles someros de la corteza y las cuales conforman una unidad ígnea mayor denominada aquí plutón La Costa, la cual aflora en el sector noreste de la sierra de Velasco. La asociación mineral, la química mineral y la geoquímica de roca total permiten definir al plutón La Costa como un clásico granitoide tipo-S, derivado de una roca fuente de composición esencialmente pelítica. Diferentes estudios demuestran que la generación de granitoides tipo-S requiere de un alto gradiente geotérmico, por lo cual el plutón La Costa indica que la corteza en esta región soportó un notable calentamiento durante la generación del magma. Sin embargo, la ausencia de datos geocronológicos impide definir el evento tectomagmático que produjo el magma primordial de este plutón.Combined petrology, mineral chemistry and whole-rock geochemistry studies reveal the presence of two peraluminous granitic units with magmatic aluminous minerals, such as garnet and white mica, and the distinctive presence of tourmaline. The evidence presented here indicates that these two facies, Anillaco and Anjullón, together with the peraluminous Santa Cruz unit studied in previous works, constitute co-sanguineous rocks, emplacemed in shallow levels of the crust, conforming a greater igneous unit, named here as La Costa pluton, that outcrops in the northeast sector of the sierra de Velasco. The mineral assemblage, the mineral chemistry and the whole-rock geochemistry allow defining the La Costa pluton as

  13. Do High-elevation Lakes Record Variations in Snowfall and Atmospheric Rivers in the Sierra Nevada of California?

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    Ashford, J.; Sickman, J. O.; Lucero, D. M.

    2014-12-01

    Understanding the underlying causes of interannual variation in snowfall and extreme hydrologic events in the Sierra Nevada is hampered by short instrumental records and the difficulties in reconstructing climate using a traditional paleo-record such as tree-rings. New paleo proxies are needed to provide a record of snowpack water content and extreme precipitation events over millennial timescales which can be used to test hypotheses regarding teleconnections between Pacific climate variability and water supply and flood risk in California. In October 2013 we collected sediment cores from Pear Lake (z = 27 m), an alpine lake in Sequoia National Park. The cores were split and characterized by P-wave velocity, magnetic susceptibility and density scanning. Radiocarbon dates indicate that the Pear Lake cores contain a 13.5K yr record of lake sediment. In contrast to other Sierra Nevada lakes previously cored by our group, high-resolution scanning revealed alternating light-dark bands (~1 mm to 5 mm thick) for most of the Pear Lake core length. This pattern was interrupted at intervals by homogenous clasts (up to 75 mm thick) ranging in grain size from sand to gravel up to 1 cm diameter. We hypothesize that the light-dark banding results from the breakdown of persistent hypolimnetic anoxia during spring snowmelt and autumn overturn. We speculate that the thicknesses of the dark bands are controlled by the duration of anoxia which in turn is controlled by the volume and duration of snowmelt. The sand to gravel sized clasts are most likely associated with extreme precipitation events resulting from atmospheric rivers intersecting the southern Sierra Nevada. We hypothesize that centimeter-sized clasts are deposited in large avalanches and that the sands are deposited in large rain events outside of the snow-cover period.

  14. Horizontes de fragipan de tipo «ison» formados por permafrost en la Sierra de Guadarrama

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    Alvarez, A.

    1988-04-01

    Full Text Available A toposecuence of soiIs that incIudes soils with fragipan of ison sort (FitzPatrick, 1974 is studied in the Sierra de Guadarrama. The presence of these soils in the high part of the mountain confirms the permafrost formation in the last glaciation. On the other band, the analitical data and tbe field observations of soils allow us to stablish, hypoteticaIIy, three stages in their evolution: 1 prewürm weathering and pedogenesis; 2 compaction and densification of the soils mass in the area affected by the permafrost; 3 truncation, fosilization and pedogenesis phenomena in the Holocene. About the climate the mean annual temperature in the last cold period must have been between 7,5 ºC and 12,5 ºC lower than now.Se estudia en la Sierra de Guadarrama una toposecuencia edáfica que incluye suelos con fragipan de tipo, «ison» (Fitz Patrick, 1974. La presencia de estos suelos en la parte alta de la sierra confirma la formación de permafrost en el último período frío. Además, los datos analíticos y las observaciones de campo permiten establecer, hipotéticamente, tres etapas en la evolución de los suelos: 1 alteración y edafización anterior al período frío; 2 compactación y densificación de la masa del suelo en las zonas afectadas por permafrost; 3 fenómenos de truncamiento, fosilización y edafización en el Holoceno. En cuanto al clima se concluye que la temperatura media anual en el último período frío debió ser entre 7,5 ºC y 12,5 ºC inferior a la actual.

  15. Distrubution of the Endocrine Disruptor Nonylphenol and the Effects of Topographical Sheilding in an Eastern Sierra Nevada Mountain Drainage

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    Lyons, R. A.; Van de Bittner, K.; Morgan Jones, S.

    2013-12-01

    Nonylphenol is a biodegradation product of nonylphenol polyethoxylates, a pervasive compound used in many industrial processes and notably in pesticides as a surfactant. Nonylphenol has been shown to act as an endocrine disruptor at low concentrations. It causes hermaphrodism, birth defects, and high mortality in fish, frogs and other amphibians. The Sierra Nevada Mountains separate the Central Valley in the west from the high desert of Mono Country on the east side of the state of California. The Central Valley represents some of the most heavily cultivated agricultural land in the United States. San Joaquin County alone had an annual pesticide use of over 8 million pounds in 2009 according to the Pesticide Action Network, compared with 4800 pounds in Mono County the same year. Fragile alpine ecosystems in the Sierra Nevadas may be highly susceptible to the effects of endocrine disruptors like nonylphenol. The distribution of nonylphenol is affected by localized topography in a steep walled montane canyon in the Eastern Sierra Nevada Mountains, Convict Creek canyon. The concentration of nonylphenol in snow and surface water increases as the elevation in Convict Creek canyon decreases in an easterly direction from not detectable at the highest elevations to as much as .01mg/L in water and 1.8 mg/L in snow at the lowest elevations. The steep head wall of Convict Creek canyon, facing southeast, provides shielding to the higher elevation lakes from deposition of compounds and particulate matter. As a canyon becomes less steep and broader, more nonylphenol is deposited. Identifying these deposition patterns may assist in determining amphibian and fish populations that are at higher risk of negative impact from these compounds.

  16. Comparative seismic and petrographic crustal study between the Western and Eastern Sierras Pampeanas region (31°S

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    P. Alvarado

    2005-12-01

    Full Text Available The ancient Sierras Pampeanas in the central west part of Argentina are a seismically active region in the back-arc of the Andes. Their crystalline basement cored uplifts extend up to 800 km east of the oceanic trench over the flat subduction segment of the Nazca plate. Approximately 40 felt crustal earthquakes, are reported per year for this region. Historic and modern seismicity indicates that the Western Sierras Pampeanas (WSP have more crustal earthquakes of greater-size than the Eastern Sierras Pampeanas (ESP. Remarkable changes in composition and structure also characterize the WSP and ESP basements. We have quantitatively compared both regions using seismological constrains. A recent regional study of moderate earthquakes shows reverse and thrust focal mechanisms occurring at depths down to 25 km in the WSP. In contrast, the ESP have reverse and strike-slip focal mechanisms of shallower depths (< 10 km. A seismic velocity structure of Vp 6.4 km/s, Vp/Vs ~1.80, and thickness 50 km, best represents the WSP crust. The ESP crust is characterized by Vp 6.0 km/s, Vp/Vs < 1.70, and thickness 30 km. These seismological determinations correlate with the interpretation of a different origin for the western and eastern terranes. The WSP show seismic properties indicative of a more mafic-ultramafic thick crust consistent with an oceanic island-arc and back-arc formation. The ESP show crustal seismic properties consistent with a higher silica content and with a formation by the collision of a continental terrane.

  17. Lateral migration of a foundering high-density root: Insights from numerical modeling applied to the southern Sierra Nevada

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    Valera, J. L.; Negredo, A. M.; Billen, M. I.; Jiménez-Munt, I.

    2014-02-01

    The southern Sierra Nevada is a geodynamically complex region where several models have been proposed to explain the rapid removal of lithospheric mantle occurring sometime between 8.0 and 3.5 Ma. Tomographic studies show the presence of an east-dipping slab-shaped fast seismic anomaly reaching to about 300 km depth below the western Sierras and Great Valley, and receiver function studies indicate a broad region of lithosphere removal. This work presents thermo-mechanical modeling of asymmetric foundering of a high-density batholithic root with lateral intrusion of asthenospheric material. The predicted evolution is controlled by: a) the upwelling of buoyant asthenosphere facilitated by the presence of a weakened lithospheric mantle adjacent to a dense batholitic root, b) the westward inflow enabled by a low viscosity lower crust, and c) negative buoyancy of a batholithic dense root. The dynamics of these models can be characterized as a slowly migrating lithosphere foundering process driven by the density anomaly of the ultramafic root, but controlled by the magnitude of the lower crustal viscosity, which determines the rate at which asthenospheric material can flow into the opening lower crustal gap. Final model-predicted upper-mantle structure is compatible with existing tomographic images and the observed V-shape geometry of the Moho below the western margin of the southern Sierra Nevada. Model-predicted topography is also generally consistent with observations, and shows a monotonous uplift of the high region since 7 Ma and presently ongoing, and an area of maximum subsidence west of the area of the V-shaped Moho, due to the pull exerted by the sinking of the high-density root.

  18. An assessment of the impacts of pesticide use on the environment and health of rice farmers in Sierra Leone.

    Science.gov (United States)

    Sankoh, Alhaji I; Whittle, Rebecca; Semple, Kirk T; Jones, Kevin C; Sweetman, Andrew J

    2016-09-01

    One of the biggest challenges faced by Sierra Leonean farmers is pest control. Birds, rodents, insects, crustaceans and other organisms can drastically reduce yields. In order to prevent these organisms from destroying their crop, farmers use pesticides. However there are reports that these chemicals are being misused and such misuse is having a negative impact on the environment and the health of the farmers. This research study aimed to investigate the use of pesticides in rice fields and its potential effects on the environment and on the farmers of Sierra Leone. Five hundred farmers and one hundred health workers across the country were interviewed. Fifty focus group discussions were also completed. Field observations were also undertaken to see how farmers apply pesticides to their farms and the possible threats these methods have on human health and the environment. It is clear that a wide range of pesticides are used by rice farmers in Sierra Leone with 60% of the pesticides used entering the country illegally. Most farmers have no knowledge about the safe handling of pesticides as 71% of them have never received any form of training. The pesticides kill both target and non-target organisms some of which enter the food chain. Cases of health problems such as nausea, respiratory disorders and blurred vision investigated in this research are significantly higher among farmers who use pesticides than those who do not use pesticides. Cases of pesticide intoxication are not investigated by health workers but results obtained from interviews with them also indicated that cases of pesticides related symptoms are significantly higher in environments where pesticides are used than those in which pesticides are not used.

  19. Epithermal uranium deposits in a volcanogenic context: the example of Nopal 1 deposit, Sierra de Pena Blanca, Mexico

    Science.gov (United States)

    Calas, G.; Angiboust, S.; Fayek, M.; Camacho, A.; Allard, T.; Agrinier, P.

    2009-12-01

    The Peña Blanca molybdenum-uranium field (Chihuahua, Mexico) exhibits over 100 airborne anomalies hosted in tertiary ignimbritic ash-flow tuffs (44 Ma) overlying the Pozos conglomerate and a sequence of Cretaceous carbonate rocks. Uranium occurrences are associated with breccia zones at the intersection of two or more fault systems. Periodic reactivation of these structures associated with Basin and Range and Rio Grande tectonic events resulted in the mobilization of U and other elements by meteoric fluids heated by geothermal activity. Trace element geochemistry (U, Th, REE) provides evidence for local mobilization of uranium under oxidizing conditions. In addition, O- and H-isotope geochemistry of kaolinite, smectite, opal and calcite suggests that argillic alteration proceeded at shallow depth with meteoric water at 25-75 °C. Focussed along breccia zones, fluids precipitated several generations of pyrite and uraninite together with kaolinite, as in the Nopal 1 mine, indicating that mineralization and hydrothermal alteration of volcanic tuffs are contemporaneous. Low δ34S values (~ -24.5 ‰) of pyrites intimately associated with uraninite suggest that the reducing conditions at the origin of the U-mineralization arise from biological activity. Later, the uplift of Sierra Pena Blanca resulted in oxidation and remobilization of uranium, as confirmed by the spatial distribution of radiation-induced defect centers in kaolinites. These data show that tectonism and biogenic reducing conditions can play a major role in the formation and remobilization of uranium in epithermal deposits. By comparison with the other uranium deposits at Sierra Pena Blanca and nearby Sierra de Gomez, Nopal 1 deposit is one of the few deposits having retained a reduced uranium mineralization.

  20. Interannual Variations in Aerosol Sources and Their Impact on Orographic Precipitation Over California's Central Sierra Nevada

    Science.gov (United States)

    Creamean, J. M.; Ault, A. P.; White, A. B.; Neiman, P. J.; Ralph, F. M.; Minnis, Patrick; Prather, K. A.

    2014-01-01

    Aerosols that serve as cloud condensation nuclei (CCN) and ice nuclei (IN) have the potential to profoundly influence precipitation processes. Furthermore, changes in orographic precipitation have broad implications for reservoir storage and flood risks. As part of the CalWater I field campaign (2009-2011), the impacts of aerosol sources on precipitation were investigated in the California Sierra Nevada. In 2009, the precipitation collected on the ground was influenced by both local biomass burning (up to 79% of the insoluble residues found in precipitation) and long-range transported dust and biological particles (up to 80% combined), while in 2010, by mostly local sources of biomass burning and pollution (30-79% combined), and in 2011 by mostly long-range transport from distant sources (up to 100% dust and biological). Although vast differences in the source of residues was observed from year-to-year, dust and biological residues were omnipresent (on average, 55% of the total residues combined) and were associated with storms consisting of deep convective cloud systems and larger quantities of precipitation initiated in the ice phase. Further, biological residues were dominant during storms with relatively warm cloud temperatures (up to -15 C), suggesting these particles were more efficient IN compared to mineral dust. On the other hand, lower percentages of residues from local biomass burning and pollution were observed (on average 31% and 9%, respectively), yet these residues potentially served as CCN at the base of shallow cloud systems when precipitation quantities were low. The direct connection of the source of aerosols within clouds and precipitation type and quantity can be used in models to better assess how local emissions versus long-range transported dust and biological aerosols play a role in impacting regional weather and climate, ultimately with the goal of more accurate predictive weather forecast models and water resource management.

  1. Dissolved Organic Matter Composition and Microbial Diversity In The Lake Tahoe Basin, Sierra Nevada, California.

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    Aluwihare, L.; Goldberg, S. J.; Ball, G. I.; Mendoza, W. G.; Simpson, A.; Kharbush, J.; Nelson, C. E.

    2014-12-01

    Dissolved organic matter (DOM) inputs into high elevation lakes of the Sierra Nevada, California are seasonally segregated, and this enables an examination of the dominant compositional features and microbial responses associated with allochthonous versus autochthonous DOM inputs. Furthermore, because lakes within this watershed have very different hydraulic residence times, extending from days (e.g., Upper Angora Lake) to centuries (Lake Tahoe), the Tahoe Basin represents an ideal experimental system in which to characterize long-lived DOM. We used a variety of analytical tools, including elemental, stable isotope and radiocarbon measurements, nuclear magnetic resonance (NMR) spectroscopy, comprehensive 2D gas chromatography coupled to time of flight (TOF) mass spectrometry and fluorescence measurements, to characterize solid phase extracted (SPE) DOM, and in some cases, whole DOM. Our data show that DOM with typical terrestrial characteristics is quickly removed in lakes with >annual water residence time, leaving behind SPE DOM that is extremely N-rich, with a functional group distribution that is consistent with protein. Furthermore, our radiocarbon measurements estimate a 100-200 year residence time for the N-rich DOM accumulating in Lake Tahoe. All of the analytical techniques distinguish samples based on lake water residence time, which indicates that the lacustrine reactor plays an important role in determining the composition of DOM that accumulates on long timescales. We also examined temporal variations in the microbial community of Lake Tahoe to identify taxa that may be involved in processing DOM from distinct sources. Our results confirm the importance of DOM as a currency for carbon and nitrogen exchange between different compartments of the terrestrial ecosystem and argue for its inclusion in models that examine the response of lake ecosystems to global change.

  2. CUSTOMERS’ PREFERENCE FOR E – BANKING SERVICES: A CASE STUDY OF SELECTED BANKS IN SIERRA LEONE

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    R. A. GBADEYAN

    2011-08-01

    Full Text Available The development and the increasing progress that is being experienced in the Information and Communication Technology have brought about a lot of changes in almost all facets of life. In the Banking Industry, it has been in the form of online banking, which is now replacing the traditional banking practice. Online banking has a lot of benefits which add value to customers’ satisfaction in terms of better quality of service offerings and at the same time enable the banks gain more competitive advantage over other competitors. There are some associated risks identified in the study that seem to hinder the success of e-banking services and thus constitute major concern to both financial institutions and customers. This paper therefore, examines, if customers’ choice of banks is influenced by the quality of e–banking services provided. Stratified sampling was used; while the survey Instrument was a developed Questionnaire comprising open ended and Likert type of questions. The Likert type questions have a 4 point scale (indicating 1 = very comfortable and 4 = uncomfortable divided into two (2 sections: personal details and customers’ e-banking preference in Sierra Leone. The instrument contained 36 items and was administered to about 400 respondents, while 360 completed and returned their Questionnaire. The statistical techniques used for the analysis were the Chi–Square and correlation. The Chi–Square analysis revealed that the quality of e–banking services offered by banks have significant influence on their customers at 95%, 3 degree of freedom. The paper recommends that various measures should be put in place to ensure more security such as installation of encrypted software, verification system of customer’s identification cards, frequent change of password, examining test questions and using mixed password such as the use of alphanumeric amongst others. The paper concludes that e –banking has become important phenomenon in

  3. Isotope variations in a Sierra Nevada snowpack and their relation to meltwater

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    Unnikrishna, P.V.; McDonnell, Jeffery J.; Kendall, C.

    2002-01-01

    Isotopic variations in melting snow are poorly understood. We made weekly measurements at the Central Sierra Snow Laboratory, California, of snow temperature, density, water equivalent and liquid water volume to examine how physical changes within the snowpack govern meltwater ??18O. Snowpack samples were extracted at 0.1 m intervals from ground level to the top of the snowpack profile between December 1991 and April 1992. Approximately 800 mm of precipitation fell during the study period with ??18O values between -21.35 and -4.25???. Corresponding snowpack ??18O ranged from -22.25 to -6.25???. The coefficient of variation of ??18O in snowpack levels decreased from -0.37 to -0.07 from winter to spring, indicating isotopic snowpack homogenization. Meltwater ??18O ranged from -15.30 to -8.05???, with variations of up to 2.95??? observed within a single snowmelt episode, highlighting the need for frequent sampling. Early snowmelt originated in the lower snowpack with higher ??18O through ground heat flux and rainfall. After the snowpack became isothermal, infiltrating snowmelt displaced the higher ??18O liquid in the lower snowpack through a piston flow process. Fractionation analysis using a two-component mixing model on the isothermal snowpack indicated that ??18O in the initial and final half of major snowmelt was 1.30??? lower and 1.45??? higher, respectively, than the value from simple mixing. Mean snowpack ??18O on individual profiling days showed a steady increase from -15.15 to -12.05??? due to removal of lower ??18O snowmelt and addition of higher ??18O rainfall. Results suggest that direct sampling of snowmelt and snow cores should be undertaken to quantify tracer input compositions adequately. The snowmelt sequence also suggests that regimes of early lower ??18O and later higher ??18O melt may be modeled and used in catchment tracing studies. ?? 2002 Elsevier Science B.V. All rights reserved.

  4. Potential effects of tree-to-shrub type conversion on streamflow in California's Sierra Nevada

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    Baguskas, S. A.; Bart, R.; Molinari, N.; Tague, C.; Moritz, M.

    2014-12-01

    There is widespread concern that changes in climate and fire regime may lead to vegetation change across California, which in turn may influence watershed hydrology. Although plant cover is known to affect numerous hydrological processes, sensitivities to vegetation type and spatial arrangement of species within watersheds are not well understood. The primary objective of our research was to generate mechanistically-based projections of how potential type conversion from forested to shrub dominated systems may affect streamflow. During the 2014 growing season, we measured ecophysiological responses (plant water status and leaf gas exchange rates) of two dominant tree and shrub species to changes in seasonal water availability at two sites within the southern Sierra Nevada Critical Zone Observatory. Plant physiological observations were used to parameterize a process-based eco-hydrological model, RHESSys. This model was used to evaluate the impact of changes in seasonal water availability and vegetation type-conversion on streamflow. Based on our field observations, shrubs and trees had similar access to water through the early part of the growing season (April-early June); however, by late July, available water to shrubs was twice that of trees (shrubs, -0.55 ± 0.08 MPa; trees, -1.07 ± 0.08 MPa, pchanges in streamflow following simulated vegetation conversion were found to affect both the timing and amount of discharge. Controls on pre vs. post-conversion streamflow included changes in interception, rooting depth, energy balance, and plant response to changes in seasonal water availability. Our research demonstrates how linking strategic field data collection and mechanistic ecohydrologic models can be used as a robust tool for assessing the potential impact of vegetation change on the water balance of an ecosystem. This is an increasingly valuable approach to inform management decisions focused on adapting strategies based on projected changes in climate.

  5. Fungal role in post-fire ecosystem recovery in Sierra Nevada National Park (Spain)

    Science.gov (United States)

    Bárcenas-Moreno, Gema; Jiménez-Morillo, Nicasio T.; Mataix-Beneyto, Jorge; Martín Sánchez, Ines

    2016-04-01

    Fire effect on soil microorganisms has been studies for decades in several ecosystems and different microbial response can be found in the bibliography depending on numerous intrinsic and extrinsic soil factors. These factors will determine preliminary soil microbial community composition, subsequent pos-fire initial colonizers and even post-fire growth media characteristics that microbial community will find to start recolonisation. Fire-induced soil bacterial proliferation is a common pattern found after fire, usually related to pH and C availability increased. But when original soil pH is not altered by fire in acid soils, microbial response can be different and fungal response can be crucial to ecosystem recovery. In this study we have compile data related to high mountain soil from Sierra Nevada National park which was affected by a wildfire in 2006 and data obtained by laboratory heating experiment, trying to elucidate the ecological role of fungi in this fragile ecosystem. On the one hand we can observe fire-induced fungal abundance proliferation estimated by plate count method 8 and 32 months after wildfire and even in a short-term (21 d) after laboratory heating at 300 °C. Six years after fire, fungal abundance was similar between samples collected in burnt and unburnt-control area but we found higher proportion of species capable to degrade PAHs (lacase activity) in burnt soil than I the unburnt one. This finding evidences the crucial role of fungal enzymatic capacities to detoxify burnt soils when fire-induced recalcitrant and even toxic carbon compounds could be partially limiting total ecosystem recovery.

  6. Flows, droughts, and aliens: factors affecting the fish assemblage in a Sierra Nevada, California, stream.

    Science.gov (United States)

    Kiernan, Joseph D; Moyle, Peter B

    2012-06-01

    The fishes of Martis Creek, in the Sierra Nevada of California (USA), were sampled at four sites annually over 30 years, 1979-2008. This long-term data set was used to examine (1) the persistence and stability of the Martis Creek fish assemblage in the face of environmental stochasticity; (2) whether native and alien fishes responded differently to a natural hydrologic regime (e.g., timing and magnitude of high and low flows); and (3) the importance of various hydrologic and physical habitat variables in explaining the abundances of native and alien fish species through time. Our results showed that fish assemblages were persistent at all sample sites, but individual species exhibited marked interannual variability in density, biomass, and relative abundance. The density and biomass of native fishes generally declined over the period of study, whereas most alien species showed no significant long-term trends. Only alien rainbow trout increased in both density and biomass at all sites over time. Redundancy analysis identified three hydrologic variables (annual 7-day minimum discharge, maximum winter discharge, and number of distinct winter floods) and two habitat variables (percentage of pool habitat and percentage of gravel substrate) that each explained a significant portion of the annual variation in fish assemblage structure. For alien taxa, their proportional contribution to the total fish assemblage was inversely related to mean annual streamflow, one-day maximum discharge in both winter and spring, and the frequency of springtime floods. Results of this study highlight the need for continuous annual monitoring of streams with highly variable flow regimes to evaluate shifts in fish community structure. Apparent successes or failures in stream management may appear differently depending on the time series of available data.

  7. On the relative contributions of wind vs. animals to seed dispersal of four Sierra Nevada pines.

    Science.gov (United States)

    Vander Wall, Stephen B

    2008-07-01

    Selective pressures that influence the form of seed dispersal syndromes are poorly understood. Morphology of plant propagules is often used to infer the means of dispersal, but morphology can be misleading. Several species of pines, for example, have winged seeds adapted for wind dispersal but owe much of their establishment to scatter-hoarding animals. Here the relative importance of wind vs. animal dispersal is assessed for four species of pines of the eastern Sierra Nevada that have winged seeds but differed in seed size: lodgepole pine (Pinus contorta murrayana, 8 mg); ponderosa pine (Pinus ponderosa ponderosa, 56 mg); Jeffrey pine (Pinus jeffreyi, 160 mg); and sugar pine (Pinus lambertiana, 231 mg). Pre-dispersal seed mortality eliminated much of the ponderosa pine seed crop (66%), but had much less effect on Jeffrey pine (32% of seeds destroyed), lodgepole pine (29%), and sugar pine (7%). When cones opened most filled seeds were dispersed by wind. Animals removed > 99% of wind-dispersed Jeffrey and sugar pine seeds from the ground within 60 days, but animals gathered only 93% of lodgepole pine seeds and 38% of ponderosa pine seeds during the same period. Animals gathered and scatter hoarded radioactively labeled ponderosa, Jeffrey, and sugar pine seeds, making a total of 2103 caches over three years of study. Only three lodgepole pine caches were found. Caches typically contained 1-4 seeds buried 5-20 mm deep, depths suitable for seedling emergence. Although Jeffrey and sugar pine seeds are initially wind dispersed, nearly all seedlings arise from animal caches. Lodgepole pine is almost exclusively wind dispersed, with animals acting as seed predators. Animals treated ponderosa pine in an intermediate fashion. Two-phased dispersal of large, winged pine seeds appears adaptive; initial wind dispersal helps to minimize pre-dispersal seed mortality whereas scatter hoarding by animals places seeds in sites with a higher probability of seedling establishment.

  8. Fossil hominin radii from the Sima de los Huesos Middle Pleistocene site (Sierra de Atapuerca, Spain).

    Science.gov (United States)

    Rodríguez, Laura; Carretero, José Miguel; García-González, Rebeca; Lorenzo, Carlos; Gómez-Olivencia, Asier; Quam, Rolf; Martínez, Ignacio; Gracia-Téllez, Ana; Arsuaga, Juan Luis

    2016-01-01

    Complete radii in the fossil record preceding recent humans and Neandertals are very scarce. Here we introduce the radial remains recovered from the Sima de los Huesos (SH) site in the Sierra de Atapuerca between 1976 and 2011 and which have been dated in excess of 430 ky (thousands of years) ago. The sample comprises 89 specimens, 49 of which are attributed to adults representing a minimum of seven individuals. All elements are described anatomically and metrically, and compared with other fossil hominins and recent humans in order to examine the phylogenetic polarity of certain radial features. Radial remains from SH have some traits that differentiate them from those of recent humans and make them more similar to Neandertals, including strongly curved shafts, anteroposterior expanded radial heads and both absolutely and relatively long necks. In contrast, the SH sample differs from Neandertals in showing a high overall gracility as well as a high frequency (80%) of an anteriorly oriented radial tuberosity. Thus, like the cranial and dental remains from the SH site, characteristic Neandertal radial morphology is not present fully in the SH radii. We also analyzed the cross-sectional properties of the SH radial sample at two different levels: mid-shaft and at the midpoint of the neck length. When standardized by shaft length, no difference in the mid-shaft cross-sectional properties were found between the SH hominins, Neandertals and recent humans. Nevertheless, due to their long neck length, the SH hominins show a higher lever efficiency than either Neandertals or recent humans. Functionally, the SH radial morphology is consistent with more efficient pronation-supination and flexion-extension movements. The particular trait composition in the SH sample and Neandertals resembles more closely morphology evident in recent human males.

  9. Effects of Large-Scale Acquisition on Food Insecurity in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Genesis Tambang Yengoh

    2015-07-01

    Full Text Available The recent phenomenon of large-scale acquisition of land for a variety of investment purposes has raised deep concerns over the food security, livelihood and socio-economic development of communities in many regions of the developing world. This study set out to investigate the food security outcomes of land acquisitions in northern Sierra Leone. Using a mixture of quantitative and qualitative research methods, the study measures the severity of food insecurity and hunger, compares the situation of food security before and after the onset of operations of a land investing company, analyzes the food security implications of producing own food versus depending on wage labour for household food needs, and evaluates initiatives put in place by the land investing company to mitigate its food insecurity footprint. Results show an increase in the severity of food insecurity and hunger. Household income from agricultural production has fallen. Employment by the land investing company is limited in terms of the number of people it employs relative to the population of communities in which it operates. Also, wages from employment by the company cannot meet the staple food needs of its employees. The programme that has been put in place by the company to mitigate its food insecurity footprint is failing because of a host of reasons that relate to organization and power relations. In conclusion, rural people are better off producing their own food than depending on the corporate structure of land investment companies. Governments should provide an enabling framework to accommodate this food security need, both in land investment operations that are ongoing and in those that are yet to operate.

  10. Marital form and infant survival among the Mende of rural Upper Bambara Chiefdom, Sierra Leone.

    Science.gov (United States)

    Isaac, B L; Feinberg, W E

    1982-09-01

    The possible relationship between marital form (monogamy versus polygamy) and reproductive success as measured by survival to 18 months among the live issue of 65 Mende women was examined. The data were collectred in early 1968 in 9 rural villages within a 5 mile radius of Pendembu, the capital town of Upper Bambara Chiefdom, Sierra Leone. 15 of the 65 women were lone wives in monogamous unions; 50 were partners to 30 different polygamous marriages. The intensity of polygamy was relatively low among the 30 husbands: 19 (63.3%) had 2 wives each, 4 (13.3%) had 3 each, 3 (10.0%) had 4 each, 1 (3.3%) had 5, and 3 (10.0%) had 6 wives each. 98.5% of the 65 women stated farming as their only economic activity apart from domestic chores; the remaining woman performed only domestic tasks. A child was considered a survivor if he or she lived approximately 18 months or longer; a non survivor is a live issue that dies before roughly 18 months. Using logit analysis, a version of log linear analysis, child survivorship to 18 months was treated as the dependent variable. Age and marital form of the mother were treated as independent variables. The independent variables were themselves strongly related, but the survival of children to age 18 months was statistically independent of the age and marital situation of their mothers. The findings were surprising in view of the very different living environments, work schedules, and basic fertility (numbers of live births) patterns found in monogamous and polygamous unions, and within the polygamous unions, as between "Big Wives" and "junior cowives."

  11. Tectonic events reflected by palaeocurrents, zircon geochronology, and palaeobotany in the Sierra Baguales of Chilean Patagonia

    Science.gov (United States)

    Gutiérrez, Nestor M.; Le Roux, Jacobus P.; Vásquez, Ana; Carreño, Catalina; Pedroza, Viviana; Araos, José; Oyarzún, José Luis; Pablo Pino, J.; Rivera, Huber A.; Hinojosa, L. F.

    2017-01-01

    The Sierra Baguales, situated north of the Torres Del Paine National Park in the Magallanes region of southern Chile, shows a well-exposed stratigraphic sequence ranging from the Late Cretaceous to late Pliocene, which presents a unique opportunity to study the evolution of sedimentological styles and trends, palaeoclimate changes, and tectonic events during this period. The depositional environment changed from a continental slope and shelf during the Cenomanian-Campanian (Tres Pasos Formation) to deltaic between the Campanian-Maastrichtian (Dorotea Formation) and estuarine in the Lutetian-Bartonian (Man Aike Formation). During the Rupelian, a continental environment with meandering rivers and overbank marshes was established (Río Leona Formation). This area was flooded in the early Burdigalian (Estancia 25 de Mayo Formation) during the Patagonian Transgression, but emerged again during the late Burdigalian (Santa Cruz Formation). Measured palaeocurrent directions in this Mesozoic-Cenozoic succession indicate source areas situated between the northeast and east-southeast during the Late Cretaceous, east-southeast during the middle Eocene, and southwest during the early Oligocene to early Miocene. This is confirmed by detrital zircon age populations in the different units, which can be linked to probable sources of similar ages in these areas. The east-southeastern provenance is here identified as the Antarctic Peninsula or its northeastern extension, which is postulated to have been attached to Fuegian Patagonia during the Eocene. The southwestern and western sources were exhumed during gradual uplift of the Southern Patagonian Andes, coinciding with a change from marine to continental conditions in the Magallanes-Austral Basin, as well as a decrease in mean annual temperature and precipitation indicated by fossil leaves in the Río Leona Formation. The rain shadow to the east of the Andes thus started to develop here during the late Eocene-early Oligocene ( 34

  12. Evaposublimation from the snow in the Mediterranean mountains of Sierra Nevada (Spain)

    Science.gov (United States)

    Herrero, Javier; José Polo, María

    2016-12-01

    In this study we quantify the evaposublimation and the energy balance of the seasonal snowpack in the Mediterranean semiarid region of Sierra Nevada, Spain (37° N). In these kinds of regions, the incidence of this return of water to the atmosphere is particularly important to the hydrology and water availability. The analysis of the evaposublimation from snow allows us to deduct the losses of water expected in the short and medium term and is critical for the efficient planning of this basic and scarce resource. To achieve this, we performed 10 field campaigns from 2009 to 2015, during which detailed measurements of mass fluxes of a controlled volume of snow were recorded using a modified version of an evaporation pan with lysimeter. Meteorological data at the site of the snow control volume were extensively monitored during the tests. With these data, a point energy balance snowmelt model was validated for the area. This model, fed with the complete meteorological data set available at the Refugio Poqueira Station (2500 m a.s.l.), let us estimate that evaposublimation losses for this site can range from 24 to 33 % of total annual ablation. This ratio is very variable throughout the year and between years, depending on the particular occurrence of snowfall and mild weather events, which is generally quite erratic in this semiarid region. Evaposublimation proceeds at maximum rates of up to 0.49 mm h-1, an order of magnitude less than maximum melt rates. However, evaposublimation occurs during 60 % of the time that snow lies, while snowmelt only takes up 10 % of this time. Hence, both processes remain close in magnitude on the annual scale.

  13. Conservation of avian diversity in the Sierra Nevada: moving beyond a single-species management focus.

    Directory of Open Access Journals (Sweden)

    Angela M White

    Full Text Available BACKGROUND: As a result of past practices, many of the dry coniferous forests of the western United States contain dense, even-aged stands with uncharacteristically high levels of litter and downed woody debris. These changes to the forest have received considerable attention as they elevate concerns regarding the outcome of wildland fire. However, attempts to reduce biomass through fuel reduction (i.e., thinning of trees are often opposed by public interest groups whose objectives include maintaining habitat for species of concern such as the spotted owl, Strix occidentalis, the northern goshawk, Accipiter gentilis, and the Pacific fisher, Martes pennanti. Whether protection of these upper-trophic level species confers adequate conservation of avian forest diversity is unknown. METHODOLOGY AND PRINCIPAL FINDINGS: We use a multi-species occurrence model to estimate the habitat associations of 47 avian species detected at 742 sampling locations within an 880-km(2 area in the Sierra Nevada. Our approach, which accounts for variations in detectability of species, estimates occurrence probabilities of all species in a community by linking species occurrence models into one hierarchical community model, thus improving inferences on all species, especially those that are rare or observed infrequently. We address how the avian community is influenced by covariates related to canopy cover, tree size and shrub cover while accounting for the impacts of abiotic variables known to affect species distributions. CONCLUSIONS AND SIGNIFICANCE: Environmental parameters estimated through our approach emphasize the importance of within and between stand-level heterogeneity in meeting biodiversity objectives and suggests that many avian species would increase under more open canopy habitat conditions than those favored by umbrella species of high conservation concern. Our results suggest that a more integrated approach that emphasizes maintaining a diversity of

  14. Characterizing Runoff and Water Yield from Headwater Catchments in the Southern Sierra Nevada

    Science.gov (United States)

    Safeeq, M.; Hunsaker, C. T.

    2015-12-01

    In a mediterranean climate where much of the annual precipitation falls during winter, the snow-capped Sierra Nevada serves as the primary source of dry season runoff that supports agriculture, industries, urban, and other ecosystems. Increased warming has led to significant reductions in mountain snowpack accumulation and earlier snowmelt throughout the western United States where most of the snow accumulates at temperatures near the freezing point. As a result, declines in dry season runoff magnitude, earlier runoff timing, and altered flood risk have been reported across the region. An important question in this context is, how to best manage forested catchments for water and other ecosystem services? We depict the differences in hydrologic response of ten catchments in the Kings River Experimental Watersheds (KREW) research project using continuous precipitation, snow, and runoff data during 2004-2014. The size of these catchments ranges from 50 to 475 ha, and they span a 600-m elevation range in the rain snow transitional zone. In terms of soil, Shaver and Gerle-Cagwin dominate the lower elevation Providence catchments, and Cagwin soils dominate the higher elevation Bull catchments. The majority of these catchments have southwest aspect, moderate average slope (i.e. annual runoff ranges between 281 to 408 mm in Providence and 436 to 656 mm in Bull catchments despite no significant difference in precipitation among KREW's four meteorological stations. However, high elevation Bull catchments receive significantly more precipitation as snow than the low elevation Providence catchments. The average runoff ratio ranges from 18% to as high as 43% among different catchments, indicating that the catchment evapotranspiration exceeds the catchment runoff. Inter-catchment variability in runoff, runoff ratio, characteristics of runoff ratio-precipitation relationship (i.e. slope and intercept), and precipitation elasticity of runoff can be primarily explained by

  15. Impact of civil war on emotion recognition: the denial of sadness in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Maria Alessandra eUmilta'

    2013-09-01

    Full Text Available Studies of children with atypical emotional experience demonstrate that childhood exposure to high levels of hostility and threat biases emotion perception. This study investigates emotion processing, in former child soldiers and non-combatant civilians. All participants have experienced prolonged violence exposure during childhood. The study, carried out in Sierra Leone, aimed to examine the effects of exposure to and forced participation in acts of extreme violence on the emotion processing of young adults war survivors. A total of 76 young, male adults (38 former child soldier survivors and 38 civilian survivors were tested in order to assess participants’ ability to identify four different facial emotion expressions from photographs and movies. Both groups were able to recognize facial expressions of emotion. However, despite their general ability to correctly identify facial emotions, participants showed a significant response bias in their recognition of sadness. Both former soldiers and civilians made more errors in identifying expressions of sadness than in the other three emotions and when mislabeling sadness participants most often described it as anger. Conversely, when making erroneous identifications of other emotions, participants were most likely to label the expressed emotion as sadness. In addition, while for three of the four emotions participants were better able to make a correct identification the greater the intensity of the expression, this pattern was not observed for sadness. During movies presentation the recognition of sadness was significantly worse for soldiers. While both former child soldiers and civilians were found to be able to identify facial emotions, a significant response bias in their attribution of negative emotions was observed. Such bias was particularly pronounced in former child soldiers. These findings point to a pervasive long-lasting effect of childhood exposure to violence on emotion processing

  16. The accuracy of matrix population model projections for coniferous trees in the Sierra Nevada, California

    Science.gov (United States)

    van Mantgem, P.J.; Stephenson, N.L.

    2005-01-01

    1 We assess the use of simple, size-based matrix population models for projecting population trends for six coniferous tree species in the Sierra Nevada, California. We used demographic data from 16 673 trees in 15 permanent plots to create 17 separate time-invariant, density-independent population projection models, and determined differences between trends projected from initial surveys with a 5-year interval and observed data during two subsequent 5-year time steps. 2 We detected departures from the assumptions of the matrix modelling approach in terms of strong growth autocorrelations. We also found evidence of observation errors for measurements of tree growth and, to a more limited degree, recruitment. Loglinear analysis provided evidence of significant temporal variation in demographic rates for only two of the 17 populations. 3 Total population sizes were strongly predicted by model projections, although population dynamics were dominated by carryover from the previous 5-year time step (i.e. there were few cases of recruitment or death). Fractional changes to overall population sizes were less well predicted. Compared with a null model and a simple demographic model lacking size structure, matrix model projections were better able to predict total population sizes, although the differences were not statistically significant. Matrix model projections were also able to predict short-term rates of survival, growth and recruitment. Mortality frequencies were not well predicted. 4 Our results suggest that simple size-structured models can accurately project future short-term changes for some tree populations. However, not all populations were well predicted and these simple models would probably become more inaccurate over longer projection intervals. The predictive ability of these models would also be limited by disturbance or other events that destabilize demographic rates. ?? 2005 British Ecological Society.

  17. Hillslope Erosion and Water Quality from the Rim Fire, Sierra Nevada, CA

    Science.gov (United States)

    Kuhn, T. J.; Austin, L. J.; Forrester, H.; DeLong, S. B.; Lever, R.; Roche, J. W.

    2014-12-01

    The Rim Fire in 2013 burned approximately 1036 km2 in the Sierra Nevada (including 312 km2 within Yosemite National Park), generating considerable public concern regarding potential impacts to the Tuolumne River watershed, in terms of water quality and water supply infrastructure serving the City of San Francisco. Land management responses included a multi-million dollar watershed treatment project on USFS lands near Cherry Creek, with similar actions suggested for areas in the Hetch Hetchy and Lake Eleanor watersheds. In response to the concern that the post-burn landscape will negatively impact water quality, we are investigating hydrologic effects and hillslope erosion in two small burned basins (2.2 and 5.2 km2) within the Tuolumne River basin in Yosemite National Park. Within a month after fire containment, sites were equipped with instrumentation to record stream stage, turbidity, and total suspended sediment. We also installed 21 sediment fences that trap all sediment silt sized and larger on moderate (20%) to steep (50%) hillslopes from 100 m2 plots within moderate and high severity burn areas. Accumulated sediment is collected, weighed, and sub-sampled after each storm event, and, analyzed for dry weight, particle size, gravimetric water content, bulk density, pH, color, carbon and nitrogen content from % fine organics, and % coarse organics. As of July 31, 2014, four discrete storm events had been sampled. Data are used to calculate annual sediment yield, and to investigate organic carbon storage, deposition, and transport. We are also collecting repeat terrestrial laser scans to assess topographic change and identify the hillslope processes that contribute to erosion and deposition at plot- and hillslope-scale. These findings provide analogs for possible changes in adjacent burned areas and to inform management decisions in response to future fires and potential impacts to water quality in areas valued by the park, the City of San Francisco and other

  18. Sources, determinants and utilization of health workers’ revenues: evidence from Sierra Leone

    Science.gov (United States)

    Bertone, Maria Paola; Lagarde, Mylene

    2016-01-01

    Exploring the entire set of formal and informal payments available to health workers (HWs) is critical to understand the financial incentives they face and devise effective incentive packages to motivate them. We investigate this issue in the context of Sierra Leone by collecting quantitative data through a survey and daily logbooks on the incomes of 266 HWs in three districts, and carrying out 39 qualitative in-depth interviews. We find that, while earnings related to the HWs official jobs represent the largest share, their income is fragmented and composed of a variety of payments, and there is a large heterogeneity in the importance of each income source within the total remuneration. Importantly, each income has different features in terms of regularity, reliability, ease of access, etc. Our analysis also reveals the determinants of the incomes received and their level based on individual and facility characteristics, and finds that these are not in line with HRH policies defined at national level. Additionally, from their narratives, it emerges that HWs are ‘managing’, in the sense both of ‘getting by’ and of enacting financial coping strategies, such as mental accounting (spending different incomes differently), income hiding to shelter it from family pressures, and re-investment of incomes to stabilize overall earnings over time, in order to ensure their livelihoods and those of their families. These strategies question the assumption of fungibility of incomes and the neutrality of increasing or regulating one rather than another of them. Together, our findings on earning and income use patterns have important policy implications for how we go about (re)thinking financial incentive strategies. PMID:27053639

  19. Effects of copper on species composition of periphyton in a Sierra Nevada, California, stream

    Energy Technology Data Exchange (ETDEWEB)

    Leland, H.V.; Carter, J.L.

    1984-06-01

    Changes in species composition of the periphyton of an oliotrophic, Sierra Nevada stream continuously dosed for 1 year at three concentrations of copper (2.5, 5 and 10..mu..g 1/sup -1/ Cu/sub T/; approximately 12, 25 and 50 ng 1/sup -1/ Cu/sup 2 +/) were determined. The numerically most abundant taxa were Bacillariophyceae (Achnanthes minutissima, Cocconeis placentula, Cymbella microcephala, C. sinuata, Fragilaria construens, F. crotonensis, Navicula spp., Synedra acus and S. rumpens), and the Cyanophyta Lynbya spp., a co-dominant during spring and summer. Population densities of Lyngbya spp. were markedly reduced at all test concentrations of copper. Population densities of the principal Chlorophyta (Spirogyra spp. and Cladophora spp.) and the diatom Amphipleura pellucida were reduced at 5 ..mu..g 1/sup -1/ Cu/sub T/. Of the twenty-two most abundant taxa, sixteen were reduced in abundance by continuous exposure to 10 ..mu..g 1/sup -1/ Cu/sub T/. There was no commensurate reduction in standing crop (total number of individuals of all taxa). Achnanthes minutissima, a co-dominant in the control, was the primary replacement species. Other taxa that were more abundant at 5 ..mu..g 1/sup -1/ Cu/sub T/ than in the control were Ceratoneis arcus, Cocconeis placentula, Navicula spp. and Synedra rumpens. Only A. minutissima and Calothrix spp. were more abundant at l10 ..mu..g 1/sup -1/ than in the control. Three resemblance measures (Canberra metric, Bray-Curtis and Dice) and diversity (Brillouin's) were evaluated for detecting differences in species composition among experimental stream sections. The Canberra metric, an index sensitive to proportional rather than absolute differences, was the most informative of these indices.

  20. Forest thinning and soil respiration in a ponderosa pine plantation in the Sierra Nevada.

    Science.gov (United States)

    Tang, Jianwu; Qi, Ye; Xu, Ming; Misson, Laurent; Goldstein, Allen H

    2005-01-01

    Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws.) plantation in the Sierra Nevada Mountains in California from June 1998 to May 2000 (before a thinning that removed 30% of the biomass), and from May to December 2001 (after thinning). Thinning increased the spatial homogeneity of soil temperature and respiration. We conducted a multivariate analysis with two independent variables of soil temperature and water and a categorical variable representing the thinning event to simulate soil respiration and assess the effect of thinning. Thinning did not change the sensitivity of soil respiration to temperature or to water, but decreased total soil respiration by 13% at a given temperature and water content. This decrease in soil respiration was likely associated with the decrease in root density after thinning. With a model driven by continuous soil temperature and water time series, we estimated that total soil respiration was 948, 949 and 831 g C m(-2) year(-1) in the years 1999, 2000 and 2001, respectively. Although thinning reduced soil respiration at a given temperature and water content, because of natural climate variability and the thinning effect on soil temperature and water, actual cumulative soil respiration showed no clear trend following thinning. We conclude that the effect of forest thinning on soil respiration is the combined result of a decrease in root respiration, an increase in soil organic matter, and changes in soil temperature and water due to both thinning and interannual climate variability.

  1. Bulk arc strain, crustal thickening, magma emplacement, and mass balances in the Mesozoic Sierra Nevada arc

    Science.gov (United States)

    Cao, Wenrong; Paterson, Scott; Saleeby, Jason; Zalunardo, Sean

    2016-03-01

    Quantifying crustal deformation is important for evaluating mass balance, material transfer, and the interplay between tectonism and magmatism in continental arcs. We present a dataset of >650 finite strain analyses compiled from published works and our own studies with associated structural, geochronologic, and geobarometric information in central and southern Sierra Nevada, California, to quantify the arc crust deformation. Our results show that Mesozoic tectonism results in 65% arc-perpendicular bulk crust shortening under a more or less plane strain condition. Mesozoic arc magmatism replaced ∼80% of this actively deforming arc crust with plutons requiring significantly greater crustal thickening. We suggest that by ∼85 Ma, the arc crust thickness was ∼80 km with a 30-km-thick arc root, resulting in a ∼5 km elevation. Most tectonic shortening and magma emplacement must be accommodated by downward displacements of crustal materials into growing crustal roots at the estimated downward transfer rate of 2-13 km/Myr. The downward transfer of crustal materials must occur in active magma channels, or in "escape channels" in between solidified plutons that decrease in size with time and depth resulting in an increase in the intensity of constrictional strain with depth. We argue that both tectonism and magmatism control the thickness of the crust and surface elevation with slight modification by surface erosion. The downward transported crustal materials initially fertilize the MASH zone thus enhancing to the generation of additional magmas. As the crustal root grows it may potentially pinch out and cool the mantle wedge and thus cause reduction of arc magmatism.

  2. The Potential of Women’s Organization for Rural Development in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Theresa Tenneh Dick

    2013-01-01

    Full Text Available Organizations are among the preferred outlets women use both to voice societal prejudices against them and to showcase their potential for rural/community development. There is an increasing advocacy for gender equality, women’s empowerment and the integration of women folks into the socio-economic, political and cultural fabrics of society. Girl-child education and women-based capacity building programs such as micro-finance, entrepreneurship, political activism, etc. have surfaced prominently on these women’s empowerment efforts. In this study, a questionnaire-driven survey is conducted in two districts in southern Sierra Leone. The survey covers 36 influential women in 36 town-level communities in the country. The study analyzes the personal and organization characteristics of the women in relation to social perceptions and rural/community development. A large percent of the women surveyed are educated, married and belong to social organizations. In addition to other social/development organizations, women’s organizations are also present in each of the surveyed communities. Most of the women organizations are local in nature and operate entirely on funds raised from within the local communities. This display of organizational ability of the surveyed rural women shows a significant perceptional shift towards recognizing women folks as productive counterparts in our societies. This trend also psychologically strengthens the women community to take on tangible responsibilities that were ones meant for men only. The analysis also shows that rural women hold managerial and other administrative positions in the organizations which are strongly oriented towards various forms of rural/community development. This is a significant positive deviation from the traditional perception which has unduly confined the women folks to the backyard for centuries now. This trend not only has the potential of benefiting the millions more women languishing in

  3. Impact of civil war on emotion recognition: the denial of sadness in Sierra Leone.

    Science.gov (United States)

    Umiltà, Maria Allessandra; Wood, Rachel; Loffredo, Francesca; Ravera, Roberto; Gallese, Vittorio

    2013-01-01

    Studies of children with atypical emotional experience demonstrate that childhood exposure to high levels of hostility and threat biases emotion perception. This study investigates emotion processing, in former child soldiers and non-combatant civilians. All participants have experienced prolonged violence exposure during childhood. The study, carried out in Sierra Leone, aimed to examine the effects of exposure to and forced participation in acts of extreme violence on the emotion processing of young adults war survivors. A total of 76 young, male adults (38 former child soldier survivors and 38 civilian survivors) were tested in order to assess participants' ability to identify four different facial emotion expressions from photographs and movies. Both groups were able to recognize facial expressions of emotion. However, despite their general ability to correctly identify facial emotions, participants showed a significant response bias in their recognition of sadness. Both former soldiers and civilians made more errors in identifying expressions of sadness than in the other three emotions and when mislabeling sadness participants most often described it as anger. Conversely, when making erroneous identifications of other emotions, participants were most likely to label the expressed emotion as sadness. In addition, while for three of the four emotions participants were better able to make a correct identification the greater the intensity of the expression, this pattern was not observed for sadness. During movies presentation the recognition of sadness was significantly worse for soldiers. While both former child soldiers and civilians were found to be able to identify facial emotions, a significant response bias in their attribution of negative emotions was observed. Such bias was particularly pronounced in former child soldiers. These findings point to a pervasive long-lasting effect of childhood exposure to violence on emotion processing in later life.

  4. Spatial modeling of coupled hydrologic-biogeochemical processes for the Southern Sierra Critical Zone Observatory

    Science.gov (United States)

    Tague, C.

    2007-12-01

    One of the primary roles of modeling in critical zone research studies is to provide a framework for integrating field measurements and theory and for generalizing results across space and time. In the Southern Sierra Critical Zone Observatory (SCZO), significant spatial heterogeneity associated with mountainous terrain combined with high inter-annual and seasonal variation in climate, necessitates the use of spatial-temporal models for generating landscape scale understanding and predictions. Science questions related to coupled hydrologic and biogeochemical fluxes within the critical zone require a framework that can account for multiple and interacting processes. One of the core tools for the SCZO will be RHESSYs (Regional hydro-ecologic simulation system). RHESSys is an existing GIS-based model of hydrology and biogeochemical cycling. For the SCZO, we use RHESSys as an open-source, objected oriented model that can be extended to incorporate findings from field-based monitoring and analysis. We use the model as a framework for data assimilation, spatial-temporal interpolation, prediction, and scenario and hypothesis generation. Here we demonstrate the use of RHESSys as a hypothesis generation tool. We show how initial RHESSys predictions can be used to estimate when and where connectivity within the critical zone will lead to significant spatial or temporal gradients in vegetation carbon and moisture fluxes. We use the model to explore the potential implications of heterogeneity in critical zone controls on hydrologic processes at two scales: micro and macro. At the micro scale, we examine the role of preferential flowpaths. At the macro scale we consider the importance of upland-riparian zone connectivity. We show how the model can be used to design efficient field experiments by, a-priori providing quantitative estimate of uncertainty and highlighting when and where measurements might most effectively reduce that uncertainty.

  5. Cambio cultural, estilo de vida, adiposidad y niveles de glucosa en una comunidad totonaca de la Sierra Norte de Puebla

    OpenAIRE

    Gastón Macín Pérez; Jorge A. Gómez Valdés; Mónica Ballesteros Romero; Samuel Canizales Quinteros; Víctor Acuña Alonzo

    2013-01-01

    En el contexto de los estudios sobre los cambios en la alimentación en las poblaciones indígenas de México se realizó un estudio en una comunidad totonaca de la Sierra Norte de Puebla con dos objetivos: 1) estimar la prevalencia de hiperglucemia y obesidad en la población adulta (N = 229) mediante análisis bioquímicos y mediciones antropométricas y 2) aproximarse a las causas y formas en que ocurrieron los cambios en la alimentación, actividad física y salud que explican el aumento de hipergl...

  6. Avifauna de la región oriente de la sierra de Huautla, Morelos, México

    OpenAIRE

    Jorge E. Ramírez Albores; Ma. Guadalupe Ramírez CEDILLO

    2002-01-01

    Se presenta una lista de la avifauna de la región oriente de la sierra de Huautla, Morelos, formada a partir de observaciones continuas de campo, de marzo de 1998 a diciembre del 2000. Se registraron 177 especies pertenecientes a 42 familias y 17 órdenes. Esta lista incluye el estatus, abundancia relativa, hábitat y gremios alimenticios de todas las especies. Las aves residentes representan 60.45% de la avifauna total, las migratorias 32.76% y las transitorias 6.77%. En cuanto a su abundancia...

  7. Indicadores nutricionales en la población infanto-juvenil de Antofagasta de la Sierra, Catamarca

    OpenAIRE

    Lomaglio, Delia Beatriz; Jalil-Colomé, J.; Lejtman, N.

    2003-01-01

    Antofagasta de la Sierra está ubicada en el NO de la provincia de Catamarca en la región de Puna, a alturas superiores a 3000 metros sobre el nivel del mar. Con el objeto de conocer el estado nutricional de la población infanto- juvenil se obtuvieron las medidas de peso y estatura, las que fueron convertidas a puntajes z y se calcularon los índices P/E, T/E y P/T. Los índices nutricionales fueron comparados con las tablas del NCHS. Se observó prevalencia alta de baja talla y prevalencia... de...

  8. Un nuevo y peculiar Odontophrynus de la sierra de Guasayán, Santiago del Estero, Argentina (Anura: Leptodactylidae

    Directory of Open Access Journals (Sweden)

    Cei, José M.

    1985-01-01

    Full Text Available Un examen crítico de la morfología y cariotipo de los Odontophrynus de las poblaciones de la Sierra de Guayasán, Santiago del Estero, Argentina, permite sustentar su estado específico, frente a las otras formas del conjunto diplo-tetradiploide del grupo americanus. La nueva especie diploide O. lavillai exhibe caracteres diferenciales significativos, somáticos, de estructura cutánea y de coloración. Se presentan datos ecológicos generales y una discusión de sus relaciones cariotípicas con las otras formas diplo-tetraploides del grupo.

  9. Hongos asociados con encinos en la porción noroeste de la Sierra de Pachuca, Hidalgo

    OpenAIRE

    M. M. Mendoza-Díaz; F. Zavala-Chávez; E. Estrada-Martínez

    2006-01-01

    Con la finalidad de determinar las especies de hongos asociadas con encinos en áreas de su distribución natural en la sierra de Pachuca, Hgo., se seleccionaron tres sitios con presencia de encinos como elemento estructural importante en la vegetación de la porción noroeste de la región. En cada sitio se trazaron parcelas para observación, donde se recolectaron cuerpos fructíferos de hongos y muestras de especies de encino en bosque de Quercus mexicana (BQM), bosque de oyamel-encino (BOE) y bo...

  10. ACTORES SOCIALES EN LA GESTIÓN DEL TERRITORIO Y RIESGOS AMBIENTALES EN LA SIERRA NORTE DE PUEBLA

    OpenAIRE

    Toscana Aparicio, Alejandra

    2012-01-01

    Esta ponencia tiene como objetivo analizar, en el contexto de la descentralización del Estado y recorte del gasto público que enfrenta México desde1982, la participación de actores sociales en la gestión del territorio y riesgos ambientales en la Sierra Norte de Puebla; área agrícola, sujeta al impacto de amenazas naturales que impactan negativamente en la calidad de vida de la población de la región, predominantemente indígena en condiciones de marginalidad. En particular se analiza el caso ...

  11. Thermal evolution and exhumation of deep-level batholithic exposures, southernmost Sierra Nevada, California

    Science.gov (United States)

    Saleeby, J.; Farley, K.A.; Kistler, R.W.; Fleck, R.J.

    2007-01-01

    The Tehachapi complex lies at the southern end of the Sierra Nevada batholith adjacent to the Neogene-Quaternary Garlock fault. The complex is composed principally of high-pressure (8-10 kbar) Cretaceous batholithic rocks, and it represents the deepest exposed levels of a continuous oblique crustal section through the southern Sierra Nevada batholith. Over the southern ???100 km of this section, structural/petrologic continuity and geochronological data indicate that ???35 km of felsic to intermediate-composition crust was generated by copious arc magmatism primarily between 105 and 99 Ma. In the Tehachapi complex, these batholithic rocks intrude and are bounded to the west by similar-composition gneissic-textured high-pressure batholithic rocks emplaced at ca. 115-110 Ma. This lower crustal complex is bounded below by a regional thrust system, which in Late Cretaceous time tectonically eroded the underlying mantle lithosphere, and in series displaced and underplated the Rand Schist subduction assemblage by low-angle slip from the outboard Franciscan trench. Geophysical and mantle xenolith studies indicate that the remnants of this shallow subduction thrust descend northward through the crust and into the mantle, leaving the mantle lithosphere intact beneath the greater Sierra Nevada batholith. This north-dipping regional structure records an inflection in the Farallon plate, which was segmented into a shallow subduc-tion trajectory to the south and a normal steeper trajectory to the north. We combine new and published data from a broad spectrum of thermochronom-eters that together form a coherent data array constraining the thermal evolution of the complex. Integration of these data with published thermobarometric and petro-genetic data also constrains the tectonically driven decompression and exhumation history of the complex. The timing of arc magmatic construction of the complex, as denoted above, is resolved by a large body of U/Pb zircon ages. High

  12. El uso del castigo físico por parte del docente, y el rendimiento de los estudiantes en la sierra peruana

    OpenAIRE

    Miranda, Alejandra

    2016-01-01

    Garantizar una educación de calidad implica contar con un ambiente adecuado, propicio al desarrollo de los estudiantes; no obstante, la violencia infantil es uno de los factores que aún afecta el ambiente escolar. Dado este problema, el objetivo del presente estudio es explorar el efecto a mediano plazo del uso del castigo físico por parte del docente en el rendimiento de los estudiantes en la sierra. Esto debido a que la sierra es una de las regiones más vulnerables por los altos índices de ...

  13. Herpetofauna del Parque Sierra de Nanchititla, estado de México, México. Lista, distribución y conservación

    Directory of Open Access Journals (Sweden)

    Gustavo Casas-Andreu

    2005-01-01

    Full Text Available The Sierra de Nanchititla Natural Park is located in the southwestern corner of the state of Mexico. Most of the park is contained in the western half of the municipality of Tejupilco, bordered on the west by the states of Michoacan and Guerrero. Physiographically it is located in the Province of Sierra Madre del Sur, in the Subprovince of Depresión del rio Balsas, and represents a transition zone of climate, flora and fauna. A total of 48 species were registered in the Nanchititla Park, including 20 amphibians and 28 reptiles, of which 21 (44% are new records for the locality

  14. Prevalencia de patologías tropicales y factores de riesgo en la comunidad indígena de bunkwimake, sierra nevada de Santa Marta

    OpenAIRE

    Dib, Juan C.; Luz Adriana Agudelo; Iván Darío Vélez

    2013-01-01

    Las enfermedades tropicales son endémicas en la Sierra Nevada de Santa Marta, sin embargo se carece de información acerca de la distribución de estas enfermedades en las comunidades indígenas que la habitan. Mediante estudios entomológicos y seroepidemiológicos, se estudiaron los factores de riesgo y la prevalencia de enfermedad de Chagas, leishmaniosis, hepatitis B y parasitosis intestinales en la comunidad indígena de Bunkwimake, ubicada en la vertiente norte de la Sierra Nevada. Los result...

  15. La fauna edafica en bosques y plantaciones de coniferas de la estacion San Lorenzo-Sierra Nevada de Santa Marta Soil fauna in forest and pine plantations from San Lorenzo station-Sierra Nevada de Santa Marta

    Directory of Open Access Journals (Sweden)

    Chamorro Bello Clara

    1999-06-01

    Full Text Available En la estacion de San Lorenzo-Sierra Nevada de Santa Marta-(2280 m. se seleccionaron suelos (Tropaquepts, bajo usos de bosque nativo y plantacion de pinos. La coleccion de las comunidades edafofaunisticas se realizo con base en la aplicacion de tecnicas de Barber y Berlesse, para su posterior determinacion hasta el nivel de familia. Se determino la biodiversidad medida en el Indice de Brillouin, las densidades poblacionales, su distribucion en el perfil del suelo, y los Indices de Riqueza y Constancia, para cada uno de los horizontes edaficos.Soils in San Lorenzo Station-Sierra Nevada de Santa Marta-(2280m were selected in two different uses: forest and pine plantations. Fauna was coleected out from the soils by Pitfall and Berlesse methods to be determinated up to family levels. Biodiversity, populations, fauna distribution into soil profile, and richness and constancy indexes, were determinated in soil horizons. Biodiversity, richness and Constancy Indexes are affected when natural condition are disturbed, generally by man action. This perturbation speed up the natural population growth when another population controllers have disappea.

  16. Structural and lithological conditioning of the large karst systems of the Sierra de los Organos, Pinar del Rio, Cuba; Condicionantes estructurales y litologicas de los grandes sistemas karsticos de la Sierra de los Organos, Pinar del Rio, Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Guanche, C.; Ramirez Hernandez, R.; Farfan Gonzalez, H.; Estevez Cruz, E.; Ordaz Hernandez, A.; Aldana Vilas, C.

    2016-07-01

    he karst, a complex phenomenon, is governed by a number of variables which dictate its genesis and evolution. Among these variables tectonic settings and lithology play the main role. In Cuba, approximately 65% of the territory is occupied by karst. The Sierra de los Organos, part of Cordillera de Guaniguanico, has some of the largest karstic systems in the country. With the aim of demonstrating the relationship between the spatial and morphological development of the underground karstic systems and the geological structure and lithology of the area, several structural and morphological measurements and field observations have been made. These measurements and observations allowing us to conclude that the karstic processes take place mainly in massive, relatively homogeneous and very thick limestone in the Sierra de los Organos. Moreover, these rocks are characterized by both low porosity and a high degree of fracturing. These karstic forms are also conditioned by the existence of various fracturing systems with general NE-SW and NW-SE orientations. Interception of these fracturing systems provides, as expected, areas with the largest volumes of karstic cavities. (Author)

  17. El basamento de la sierra de San Luis: Nuevas evidencias magnéticas y sus implicancias tectónicas The basement of Sierra de San Luis: New magnetic evidence and tectonic implication

    Directory of Open Access Journals (Sweden)

    CJ Chernicoff

    2003-12-01

    Full Text Available Los mapas aeromagnéticos disponibles de las sierras de San Luis y Comechingones en el sector sudoriental de las Sierras Pampeanas de Argentina, permiten examinar las características geológicas y estructurales de las unidades metamórficas e intrusivas del basamento de la región. A través de la aplicación del filtro de continuación ascendente a los datos del campo magnético total reducido al polo, se ha podido observar la configuración profunda de las distintas unidades. Entre ellas se destaca la secuencia supracortical, en parte correspondiente a la Formación San Luis, que permite reconstruir en varios sectores de la región, en algunos casos subaflorante, una importante sucesión de rocas metasedimentarias de hasta 3 km de espesor, que es interpretada como perteneciente a depósitos de una cuenca de antepaís formada con posterioridad a la orogenia pampeana, alrededor de los 530 Ma. Se caracterizan las distintas unidades metamórficas e ígneas a partir de su señal magnética, y sobre esta base se presenta una sección estructural profunda, que sirve de base para proponer la evolución tectónica del basamento de este sector de las Sierras Pampeanas. Éste registra a partir de la orogenia pampeana la instalación de un arco magmático con su respectiva cuenca de trasarco durante el Cámbrico tardío y el Ordovícico temprano, los que son cerrados y deformados durante la colisión del terreno de Cuyania en el Ordovícico medio.The available aeromagnetic maps of the Sierras de San Luis and Comechingones in the south-eastern sector of the Sierras Pampeanas of Argentina, show the geologic and structural characteristics of the metamorphic and intrusive units of the basement of the region. Through the upward continuation filter applied to the magnetic data, it is possible to view the depth to the different units. Among them it stands out the supracrustal sequence partly equivalent to the San Luis Formation, interpreted as foreland basin

  18. Getting the 'blues': the existence, diffusion and influence of pornography on young peoples' sexual health in Sierra Leone.

    Science.gov (United States)

    Day, Andrea

    2014-01-01

    While substantial research has examined the effects of pornography on young people in developed societies, existing studies fall short in addressing how sexually-explicit material affects young people in developing countries. The importance of such knowledge increases as the globalising effects of technology expand young peoples' access and exposure to pornography. During the summer of 2012, a study was undertaken in Sierra Leone examining factors affecting young peoples' sexual and reproductive health. The research assessed the influence of HIV knowledge, communication about sex, civil war and contraception myths on sexual behaviours, while remaining open to unanticipated factors. During data collection, respondents identified pornography, also called blues, as an influential factor, detailing its newfound accessibility driven by improved access to information and communication technologies in the country. Respondents also addressed several presumed ways in which pornography impacts young peoples' decisions about sexual health. The following study examines perceived effects of young peoples' exposure to pornography based on existing literature. It then outlines the findings of research conducted in Sierra Leone, drawing on primary data from the respondents and relevant published literature and concludes with proposals for addressing its negative effects.

  19. Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California

    Energy Technology Data Exchange (ETDEWEB)

    Cisneros, Ricardo, E-mail: rcisneros@fs.fed.u [USDA Forest Service, Pacific Southwest Region, 1600 Tollhouse Road, Clovis, CA 93611 (United States); Bytnerowicz, Andrzej, E-mail: abytnerowicz@fs.fed.u [USDA Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Dr., Riverside, CA 92507 (United States); Schweizer, Donald, E-mail: dschweizer@fs.fed.u [USDA Forest Service, Pacific Southwest Region, 1600 Tollhouse Road, Clovis, CA 93611 (United States); Zhong, Sharon, E-mail: zhongs@msu.ed [Department of Geography, Michigan State University, 116 Geography Building East, Lansing, MI 48824-1117 (United States); Traina, Samuel, E-mail: straina@ucmerced.ed [Environmental Systems Graduate Group, University of California Merced, 5200 North Lake Road, Merced, CA 95343 (United States); Bennett, Deborah H., E-mail: dhbennett@ucdavis.ed [Department of Public Health Sciences, University of California Davis, One Shields Avenue, TB 169 Davis, CA 95616 (United States)

    2010-10-15

    Two-week average concentrations of ozone (O{sub 3}), nitric acid vapor (HNO{sub 3}) and ammonia (NH{sub 3}) were measured with passive samplers during the 2002 summer season across the central Sierra Nevada Mountains, California, along the San Joaquin River drainage. Elevated concentrations of the pollutants were determined with seasonal means for individual sites ranging between 62 and 88 ppb for O{sub 3}, 1.0-3.8 {mu}g m{sup -3} for HNO{sub 3}, and 2.6-5.2 {mu}g m{sup -3} for NH{sub 3}. Calculated O{sub 3} exposure indices were very high, reaching SUM00-191 ppm h, SUM60-151 ppm h, and W126-124 ppm h. Calculated nitrogen (N) dry deposition ranged from 1.4 to 15 kg N ha{sup -1} for maximum values, and 0.4-8 kg N ha{sup -1} for minimum values; potentially exceeding Critical Loads (CL) for nutritional N. The U.S., California, and European 8 h O{sub 3} human health standards were exceeded during 104, 108, and 114 days respectively, indicating high risk to humans from ambient O{sub 3}. - Ozone concentrations remained unchanged while those of nitric acid vapor and ammonia decreased along the river drainage crossing the Sierra Nevada Mountains.

  20. Structure and regional significance of the Late Permian(?) Sierra Nevada - Death Valley thrust system, east-central California

    Science.gov (United States)

    Stevens, C.H.; Stone, P.

    2005-01-01

    An imbricate system of north-trending, east-directed thrust faults of late Early Permian to middle Early Triassic (most likely Late Permian) age forms a belt in east-central California extending from the Mount Morrison roof pendant in the eastern Sierra Nevada to Death Valley. Six major thrust faults typically with a spacing of 15-20 km, original dips probably of 25-35??, and stratigraphic throws of 2-5 km compose this structural belt, which we call the Sierra Nevada-Death Valley thrust system. These thrusts presumably merge into a de??collement at depth, perhaps at the contact with crystalline basement, the position of which is unknown. We interpret the deformation that produced these thrusts to have been related to the initiation of convergent plate motion along a southeast-trending continental margin segment probably formed by Pennsylvanian transform truncation. This deformation apparently represents a period of tectonic transition to full-scale convergence and arc magmatism along the continental margin beginning in the Late Triassic in central California. ?? 2005 Elsevier B.V. All rights reserved.

  1. In-situ monitoring of California's drought: Impacts on key hydrologic variables in the Southern Sierra Nevada

    Science.gov (United States)

    Oroza, C.; Zheng, Z.; Zhang, Z.; Glaser, S. D.; Bales, R. C.; Conklin, M. H.

    2015-12-01

    Like many semi-arid regions, California relies on seasonal snowmelt from the Sierra Nevada mountain range to provide freshwater allocations for multiple stakeholders throughout the year. The magnitude and timing of runoff from these regions is being altered by consecutive years of drought, affecting downstream ecosystems, hydropower operations, and deliveries to agriculture and urban water users. Understanding the long-term effect of drought on the montane water balance requires temporally continuous, in-situ measurements of key hydrologic variables across large spatial domains. We discuss a seven-year dataset from the Southern Sierra Critical Zone Observatory, which includes co-located measurements of snowpack, soil moisture, and soil temperature in the Kings River watershed. We investigate how these key hydrologic variables are affected as the region transitions from winters that have nearly continuous snow cover (2008-2011) to winters with extended snow-on, snow-off periods (2012-2014). For water year 2014, we observe a 93% decline in average snowpack, a 35% decline in average soil moisture, and a 25% increase in average soil temperature compared to a wet-year index of each variable. We discuss the effect of physiographic features, including slope, aspect, elevation, and canopy coverage on the changes observed in each variable. Finally, we use sparse inverse covariance estimation to investigate the changing conditional relationships throughout the observatory in wet and dry years.

  2. Indicadores nutricionales en la población infanto-juvenil de Antofagasta de la Sierra, Catamarca

    Directory of Open Access Journals (Sweden)

    Lomaglio, Delia Beatriz

    2003-01-01

    Full Text Available Antofagasta de la Sierra está ubicada en el NO de la provincia de Catamarca en la región de Puna, a alturas superiores a 3000 metros sobre el nivel del mar. Con el objeto de conocer el estado nutricional de la población infanto- juvenil se obtuvieron las medidas de peso y estatura, las que fueron convertidas a puntajes z y se calcularon los índices P/E, T/E y P/T. Los índices nutricionales fueron comparados con las tablas del NCHS. Se observó prevalencia alta de baja talla y prevalencia... de bajo peso. Si bien es conocido el efecto de la hipoxia de alturas extremas sobre el crecimiento, en el caso de Antofagasta de la Sierra se asocian otros factores, en general presentes también en otras poblaciones de altura, como condiciones sanitarias, socio-económicas y nutricionales deficitarias y que dificultan el análisis.

  3. Female Genital Mutilation in Sierra Leone: Forms, Reliability of Reported Status, and Accuracy of Related Demographic and Health Survey Questions

    Directory of Open Access Journals (Sweden)

    Owolabi Bjälkander

    2013-01-01

    Full Text Available Objective. To determine forms of female genital mutilation (FGM, assess consistency between self-reported and observed FGM status, and assess the accuracy of Demographic and Health Surveys (DHS FGM questions in Sierra Leone. Methods. This cross-sectional study, conducted between October 2010 and April 2012, enrolled 558 females aged 12–47 from eleven antenatal clinics in northeast Sierra Leone. Data on demography, FGM status, and self-reported anatomical descriptions were collected. Genital inspection confirmed the occurrence and extent of cutting. Results. All participants reported FGM status; 4 refused genital inspection. Using the WHO classification of FGM, 31.7% had type Ib; 64.1% type IIb; and 4.2% type IIc. There was a high level of agreement between reported and observed FGM prevalence (81.2% and 81.4%, resp.. There was no correlation between DHS FGM responses and anatomic extent of cutting, as 2.7% reported pricking; 87.1% flesh removal; and 1.1% that genitalia was sewn closed. Conclusion. Types I and II are the main forms of FGM, with labia majora alterations in almost 5% of cases. Self-reports on FGM status could serve as a proxy measurement for FGM prevalence but not for FGM type. The DHS FGM questions are inaccurate for determining cutting extent.

  4. New foot remains from the Gran Dolina-TD6 Early Pleistocene site (Sierra de Atapuerca, Burgos, Spain).

    Science.gov (United States)

    Pablos, Adrián; Lorenzo, Carlos; Martínez, Ignacio; Bermúdez de Castro, José María; Martinón-Torres, María; Carbonell, Eudald; Arsuaga, Juan Luis

    2012-10-01

    This paper presents and describes new foot fossils from the species Homo antecessor, found in level TD6 of the site of Gran Dolina (Sierra de Atapuerca, Burgos, Spain). These new fossils consist of an almost complete left talus (ATD6-95) and the proximal three-quarters of a right fourth metatarsal (ATD6-124). The talus ATD6-95 is tentatively assigned to Hominin 10 of the TD6 sample, an adult male specimen with which the second metatarsal ATD6-70+107 (already published) is also tentatively associated. Analysis of these fossils and other postcranial remains has made possible to estimate a stature similar to those of the specimens from the Middle Pleistocene site of Sima de los Huesos (Sierra de Atapuerca, Burgos, Spain). The morphology of the TD6 metatarsals does not differ significantly from that of modern humans, Neanderthals and the specimens from Sima de los Huesos. Talus ATD6-95, however, differs from the rest of the comparative samples in being long and high, having a long and wide trochlea, and displaying a proportionally short neck.

  5. A seismological and petrological crustal model for the southwest of the Sierra de Pie de Palo, province of San Juan

    Directory of Open Access Journals (Sweden)

    Brígida Castro de Machuca

    2012-06-01

    Full Text Available A seismic velocity analysis from teleseismic receiver functions recorded in the southwestern fank of the Sierra de Pie de Palo (Western Sierras Pampeanas, Argentina, is compared with seismic properties directly calculated from lithological composition. The seismological results show an upper layer located in the first 13 km depth. A deeper contrast in seismic velocities is found at a depth of 28 km; the petrological results indicate a composition compatible with observed greenschist and amphibolite facies mafic rocks up to this depth. The receiver function measurements at 13 km and 28 km depths could be interpreted as two potential décollement levels that might have favoring a mechanism to thicken the whole crust, which produces a receiver function Moho signal located at 47 km depth. In addition, the lower crust between 28 km and 47 km exhibits high seismic P-wave velocities and Vp/Vs ratio (> 1.80 that are representative of a densification consistent with upper amphibolite to granulite/ecoglite facies lithologies. Based on these results, the combined petrological and seismological analyses suggest the continuation of the same mafic-crust outcropping lithologies into the lower levels of the 47-km thickened crust, which could be part of the Pie de Palo Complex ophiolite belt or the Precordillera basement.

  6. Development of a Statistical Model for Estimating Spatial and Temporal Ambient Ozone Patterns in the Sierra Nevada, California

    Directory of Open Access Journals (Sweden)

    Haiganoush K. Preisler

    2002-01-01

    Full Text Available Statistical approaches for modeling spatially and temporally explicit data are discussed for 79 passive sampler sites and 9 active monitors distributed across the Sierra Nevada, California. A generalized additive regression model was used to estimate spatial patterns and relationships between predicted ozone exposure and explanatory variables, and to predict exposure at nonmonitored sites. The fitted model was also used to estimate probability maps for season average ozone levels exceeding critical (or subcritical levels in the Sierra Nevada region. The explanatory variables — elevation, maximum daily temperature, and precipitation and ozone level at closest active monitor — were significant in the model. There was also a significant mostly east-west spatial trend. The between-site variability had the same magnitude as the error variability. This seems to indicate that there still exist important site features not captured by the variables used in the analysis and that may improve the accuracy of the predictive model in future studies. The fitted model using robust techniques had an overall R2 value of 0.58. The mean standard deviation for a predicted value was 6.68 ppb.

  7. The relationships between insoluble precipitation residues, clouds, and precipitation over California's southern Sierra Nevada during winter storms

    Science.gov (United States)

    Creamean, Jessie M.; White, Allen B.; Minnis, Patrick; Palikonda, Rabindra; Spangenberg, Douglas A.; Prather, Kimberly A.

    2016-09-01

    Ice formation in orographic mixed-phase clouds can enhance precipitation and depends on the type of aerosols that serve as ice nucleating particles (INPs). The resulting precipitation from these clouds is a viable source of water, especially for regions such as the California Sierra Nevada. Thus, a better understanding of the sources of INPs that impact orographic clouds is important for assessing water availability in California. This study presents a multi-site, multi-year analysis of single-particle insoluble residues in precipitation samples that likely influenced cloud ice and precipitation formation above Yosemite National Park. Dust and biological particles represented the dominant fraction of the residues (64% on average). Cloud glaciation, determined using satellite observations, not only depended on high cloud tops (>5.9 km) and low temperatures (prevalence of ice-phase clouds occurred in conjunction with biologically-rich residues and mineral dust rich in calcium, followed by iron and aluminosilicates. Dust and biological particles are known to be efficient INPs, thus these residues likely influenced ice formation in clouds above the sites and subsequent precipitation quantities reaching the surface during events with similar meteorology. The goal of this study is to use precipitation chemistry information to gain a better understanding of the potential sources of INPs in the south-central Sierra Nevada, where cloud-aerosol-precipitation interactions are poorly understood and where mixed-phase orographic clouds represent a key element in the generation of precipitation and thus the water supply in California.

  8. Petrología, evolución geodinámica y georrecursos del Espacio Natural de Sierra Nevada

    Directory of Open Access Journals (Sweden)

    Díaz Puga, M. A.

    2007-12-01

    Full Text Available We show the spatial distribution of the various geological formations that make up the Veleta and Mulhacén Complexes into the Sierra Nevada Park and illustrate, with macro- and microscopic photographs, their most characteristic types of rock. The Veleta and Mulhacén Complexes were previously considered together as the Nevado-Filábride Complex. They constitute the deepest units of the Betic Cordilleras and crop out in Sierra Nevada forming the highest pics of the Iberian Peninsula. The Veleta Complex (VC is formed of several thousand metres of graphite-bearing micaschists and crops out as a series of tectonic windows below the Mulhacén Complex (MC. This latter complex comprises two thrust nappes of crustal origin, composed of a Palaeozoic basement and Mesozoic cover series, between which a Jurassic-Cretaceous ophiolitic nappe is tectonically intercalated. Within the MC nappes of crustal origin, there appear meta-granitic rocks, generated in a late-Hercynian syn-collisional magmatism and a Permian to Triassic, post-collisional intraplate, acidic-to-intermediate volcanism. The ophiolitic nappe is composed of basic, ultramafic and sedimentary rocks affected by ocean-floor and orogenic metamorphism. The basic rocks mainly retain their original MORB character. The ultramafic rocks are serpentinites and secondary harzburgites containing partly rodingitized meta-basaltic dykes. The Alpine metamorphism developed eclogite facies followed by Ab-Ep amphibolite facies in the MC and Ab-Ep amphibolite facies followed by greenschist facies in the VC. The different tectonic units forming the Veleta and Mulhacén Complexes, so as the Soportujar Formation, which was deposited over the MC units during an alpine intraorogenic stage, were defined from outcrops very well represented into the Natural Space of Sierra Nevada. These outcrops constitute a series of petrological georesources, which are essential to reconstruct the origin and petrogenetic evolution of

  9. Valuing year-to-go hydrologic forecast improvements for a peaking hydropower system in the Sierra Nevada

    Science.gov (United States)

    Rheinheimer, David E.; Bales, Roger C.; Oroza, Carlos A.; Lund, Jay R.; Viers, Joshua H.

    2016-05-01

    We assessed the potential value of hydrologic forecasting improvements for a snow-dominated high-elevation hydropower system in the Sierra Nevada of California, using a hydropower optimization model. To mimic different forecasting skill levels for inflow time series, rest-of-year inflows from regression-based forecasts were blended in different proportions with representative inflows from a spatially distributed hydrologic model. The statistical approach mimics the simpler, historical forecasting approach that is still widely used. Revenue was calculated using historical electricity prices, with perfect price foresight assumed. With current infrastructure and operations, perfect hydrologic forecasts increased annual hydropower revenue by 0.14 to 1.6 million, with lower values in dry years and higher values in wet years, or about $0.8 million (1.2%) on average, representing overall willingness-to-pay for perfect information. A second sensitivity analysis found a wider range of annual revenue gain or loss using different skill levels in snow measurement in the regression-based forecast, mimicking expected declines in skill as the climate warms and historical snow measurements no longer represent current conditions. The value of perfect forecasts was insensitive to storage capacity for small and large reservoirs, relative to average inflow, and modestly sensitive to storage capacity with medium (current) reservoir storage. The value of forecasts was highly sensitive to powerhouse capacity, particularly for the range of capacities in the northern Sierra Nevada. The approach can be extended to multireservoir, multipurpose systems to help guide investments in forecasting.

  10. Structural Evolution of the East Sierra Valley System (Owens Valley and Vicinity, California: A Geologic and Geophysical Synthesis

    Directory of Open Access Journals (Sweden)

    Richard J. Blakely

    2013-04-01

    Full Text Available The tectonically active East Sierra Valley System (ESVS, which comprises the westernmost part of the Walker Lane-Eastern California Shear Zone, marks the boundary between the highly extended Basin and Range Province and the largely coherent Sierra Nevada-Great Valley microplate (SN-GVm, which is moving relatively NW. The recent history of the ESVS is characterized by oblique extension partitioned between NNW-striking normal and strike-slip faults oriented at an angle to the more northwesterly relative motion of the SN-GVm. Spatially variable extension and right-lateral shear have resulted in a longitudinally segmented valley system composed of diverse geomorphic and structural elements, including a discontinuous series of deep basins detected through analysis of isostatic gravity anomalies. Extension in the ESVS probably began in the middle Miocene in response to initial westward movement of the SN-GVm relative to the Colorado Plateau. At ca. 3–3.5 Ma, the SN-GVm became structurally separated from blocks directly to the east, resulting in significant basin-forming deformation in the ESVS. We propose a structural model that links high-angle normal faulting in the ESVS with coeval low-angle detachment faulting in adjacent areas to the east.

  11. Ignimbritas riolíticas neoproterozoicas en la Sierra Norte de Córdoba: ¿evidencia de un arco magmático temprano en el ciclo Pampeano? Neoproterozoic rhyolite ignimbrites in the Sierra Norte de Córdoba: evidence of an early magmatic arc in the Pampean cycle?

    Directory of Open Access Journals (Sweden)

    EJ Llambías

    2003-12-01

    Full Text Available La Sierra Norte forma parte de las Sierras Pampeanas de Córdoba por lo cual las principales intrusiones graníticas y el metamorfismo están relacionadas al ciclo orogénico Pampeano. La mayor diferencia con las Sierras de Córdoba es que en Sierra Norte el grado metamórfico es bajo y las intrusiones son superficiales. La Sierra Norte está compuesta por pequeños afloramientos de metasedimentitas, plutones de granodiorita y granito y cuerpos subvolcánicos relacionados a los últimos estadios del batolito. En este trabajo describimos mantos de ignimbritas intercalados en los metaconglomerados de la Formación La Lidia. Las ignimbritas están moderadamente soldadas y está compuestas por aproximadamente 15 % de porfiroclastos de cuarzo, feldespato potásico y plagioclasa totalmente alterada. La pasta consiste de trizas vítreas devitrificadas. La edad U/Pb convencional en circones dio 584+22/-14 Ma y es interpretada como la edad de cristalización. Tanto las ignimbritas como la roca de caja han sido afectadas por un metamorfismo en facies prehnita-pumpellita que alteró la plagioclasa en zoicita, sericita y pumpellita. Las ignimbritas silícicas neoproterozoicas, conjuntamente con el batolito calcoalcalino que le suceden sugiere la existencia de un arco magmático asociado al margen continental activo de Gondwana. Este arco habría estado activo desde el Neoproterozoico hasta el Cámbrico, con una duración de más de 60 Ma. La correlación de las metasedimentitas y volcanitas neoproterozoicas con la Formación Puncoviscana es posible.The Sierra Norte belongs to the Sierras Pampeanas of Córdoba and like in the Sierras de Córdoba the main granitic intrusions, metamorphism and deformation are related to the Pampean orogenic cycle. The most important difference with Sierras de Córdoba is that Sierra Norte shows a weaker deformation and a lower grade metamorphism. Sierra Norte consists of small outcrops of metasedimentary rocks intruded by

  12. Groundwater-quality data for the Sierra Nevada study unit, 2008: Results from the California GAMA program

    Science.gov (United States)

    Shelton, Jennifer L.; Fram, Miranda S.; Munday, Cathy M.; Belitz, Kenneth

    2010-01-01

    Groundwater quality in the approximately 25,500-square-mile Sierra Nevada study unit was investigated in June through October 2008, as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Sierra Nevada study was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems in the study unit, and to facilitate statistically consistent comparisons of groundwater quality throughout California. The primary aquifer systems (hereinafter, primary aquifers) are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for public and community drinking-water supplies. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface. In the Sierra Nevada study unit, groundwater samples were collected from 84 wells (and springs) in Lassen, Plumas, Butte, Sierra, Yuba, Nevada, Placer, El Dorado, Amador, Alpine, Calaveras, Tuolumne, Madera, Mariposa, Fresno, Inyo, Tulare, and Kern Counties. The wells were selected on two overlapping networks by using a spatially-distributed, randomized, grid-based approach. The primary grid-well network consisted of 30 wells, one well per grid cell in the study unit, and was designed to provide statistical representation of groundwater quality throughout the entire study unit. The lithologic grid-well network is a secondary grid that consisted of the wells in the primary grid-well network plus 53 additional wells and was designed to provide statistical representation of groundwater quality in each of the four major lithologic units in the Sierra

  13. The ancestral cascades arc: Cenozoic evolution of the central Sierra Nevada (California) and the birth of the new plate boundary

    Science.gov (United States)

    Busby, C.J.; Hagan, J.C.; Putirka, K.; Pluhar, C.J.; Gans, P.B.; Wagner, D.L.; Rood, D.; DeOreo, S.B.; Skilling, I.

    2008-01-01

    We integrate new stratigraphic, structural, geochemical, geochronological, and magnetostratigraphic data on Cenozoic volcanic rocks in the central Sierra Nevada to arrive at closely inter-related new models for: (1) the paleogeography of the ancestral Cascades arc, (2) the stratigraphic record of uplift events in the Sierra Nevada, (3) the tectonic controls on volcanic styles and compositions in the arc, and (4) the birth of a new plate margin. Previous workers have assumed that the ancestral Cascades arc consisted of stratovolcanoes, similar to the modern Cascades arc, but we suggest that the arc was composed largely of numerous, very small centers, where magmas frequently leaked up strands of the Sierran frontal fault zone. These small centers erupted to produce andesite lava domes that collapsed to produce block-and-ash flows, which were reworked into paleocanyons as volcanic debris flows and streamflow deposits. Where intrusions rose up through water-saturated paleocanyon fill, they formed peperite complexes that were commonly destabilized to form debris flows. Paleocanyons that were cut into Cretaceous bedrock and filled with Oligocene to late Miocene strata not only provide a stratigraphic record of the ancestral Cascades arc volcanism, but also deep unconformities within them record tectonic events. Preliminary correlation of newly mapped unconformities and new geochronological, magnetostratigraphic, and structural data allow us to propose three episodes of Cenozoic uplift that may correspond to (1) early Miocene onset of arc magmatism (ca. 15 Ma), (2) middle Miocene onset of Basin and Range faulting (ca. 10 Ma), and (3) late Miocene arrival of the triple junction (ca. 6 Ma), perhaps coinciding with a second episode of rapid extension on the range front. Oligocene ignimbrites, which erupted from calderas in central Nevada and filled Sierran paleocanyons, were deeply eroded during the early Miocene uplift event. The middle Miocene event is recorded by growth

  14. Unprecedented remote sensing data over King and Rim megafires in the Sierra Nevada Mountains of California.

    Science.gov (United States)

    Stavros, E Natasha; Tane, Zachary; Kane, Van R; Veraverbeke, Sander; McGaughey, Robert J; Lutz, James A; Ramirez, Carlos; Schimel, David

    2016-11-01

    Megafires have lasting social, ecological, and economic impacts and are increasing in the western contiguous United States. Because of their infrequent nature, there is a limited sample of megafires to investigate their unique behavior, drivers, and relationship to forest management practices. One approach is to characterize critical information pre-, during, and post-fire using remote sensing. In August 2013, the Rim Fire burned 104,131 ha and in September 2014, the King Fire burned 39,545 ha. Both fires occurred in California's Sierra Nevada. The areas burned by these fires were fortuitously surveyed by airborne campaigns, which provided the most recent remote sensing technologies not currently available from satellite. Technologies include an imaging spectrometer spanning the visible to shortwave infrared (0.38-2.5 μm), a multispectral, high-spatial resolution thermal infrared (3.5-13 μm) spectroradiometer, and Light Detection and Ranging that provide spatial resolutions of pixels from 1 × 1 m to 35 × 35 m. Because of the unique information inherently derived from these technologies before the fires, the areas were subsequently surveyed after the fires. We processed and provide free dissemination of these airborne datasets as products of surface reflectance, spectral metrics and forest structural metrics ( http://dx.doi.org/10.3334/ORNLDAAC/1288). These data products provide a unique opportunity to study relationships among and between remote sensing observations and fuel and fire characteristics (e.g., fuel type, condition, structure, and fire severity). The novelty of these data is not only in the unprecedented types of information available from them before, during, and after two megafires, but also in the synergistic use of multiple state of the art technologies for characterizing the environment. The synergy of these data can provide novel information that can improve maps of fuel type, structure, abundance, and condition that may improve

  15. Estratigrafía de la cuenca de vinchina (terciario, sierras pampeanas, provincia de la Rioja

    Directory of Open Access Journals (Sweden)

    Patricia L Cioccili

    2010-03-01

    Full Text Available La cuenca de Vinchina, en el noroeste de la provincia de La Rioja, conforma uno de los depocentros cenozoicos del antepaís fracturado (broken foreland en el segmento de Sierras Pampeanas-Famatina-Precordillera-Cordillera Frontal de los Andes. Las fases iniciales del relleno de la cuenca están representadas por delgados depósitos de sistemas fluviales y lacustres efímeros asignados a la Formación Puesto La Flecha (Paleoceno-Eoceno Temprano, la cual es cubierta en forma neta por sedimentitas eólicas de la Formación Vallecito (Eoceno. Por encima, mediante una leve discordancia erosiva, se encuentra la Formación Vinchina (Oligoceno-Mioceno Temprano? dominada por secuencias generadas en sistemas fluviales areno-pelíticos y arenoconglomerádicos depositados bajo condiciones de clima semiárido. Dentro de esta unidad se ha diferenciado el miembro inferior, dominado por depósitos areno-pelíticos, y el superior que cubre al anterior mediante una superficie erosiva de bajo ángulo tapizada por niveles de ortoconglomerados polimícticos (discordancias progresivas. La Formación Toro Negro (Mioceno-Plioceno Temprano cubre mediante una discordancia erosiva a la Formación Vinchina. El miembro inferior de la Formación Toro Negro está dominado por depósitos areno-pelíticos sedimentados en sistemas fluviales anastomosados con baja proporción de conglomerados. Por su parte, el miembro superior, que cubre mediante una leve discordancia erosiva a la unidad infrayacente, está constituido por depósitos conglomerádicos correspondientes a sistemas fluviales entrelazados y a bajadas dominadas por flujos canalizados. Finalmente, se encuentran los depósitos de abanicos aluviales de la Formación El Corral (Plioceno. Este nuevo cuadro estratigráfico para la cuenca de Vinchina permite establecer la conexión en su estadio inicial con la cuenca de La Troya, para luego evolucionar en forma independiente (antepaís fracturado.

  16. Los diques comendíticos de Papachacra (Catamarca: magmatismo peralcalino en sierras Pampeanas orientales

    Directory of Open Access Journals (Sweden)

    Fernando Colombo

    2010-03-01

    Full Text Available En Papachacra (Provincia de Catamarca, NO de Argentina hay un plutón compuesto por varios tipos diferentes de granitoides de tipo A con afinidad alcalina. Las rocas más tardías son riolitas peralcalinas (comenditas, que forman diques de hasta 50 cm atravesando el granito biotítico El Portezuelo, el cual está genéticamente desvinculado. Tienen textura porfírica y están compuestas por fenocristales de feldespato potásico (Or97-98 Ab2-3 y egirina (Ac94-98 en una mesostasis afanítica de cuarzo, feldespato potásico, albita, egirina y anfíbol litífero relacionado a la flúor-ferro-leakeíta. Los minerales accesorios son ilmenita, magnetita, óxidos del grupo del pirocloro, epidoto rico en tierras raras, zircón intersticial, monacita- (Ce y un óxido de Nb-Y-Fe no identificado. El contenido de SiO2 varía entre 68,28 y 69,33%, con muy bajo Mg, Ca, Ba, Sr y Eu, y altas concentraciones de Nb (399-409 ppm, Ta (16-34 ppm, Th (46-84 ppm, Y (101-192 ppm, Zn (280-320 ppm, Ga (42-47 ppm y especialmente Zr (2324-3000 ppm. Las comenditas se intruyeron durante un evento magmático anorogénico. Un estudio isotópico (Rb-Sr de reconocimiento hecho a rocas relacionadas indica una edad de 295 + 8 Ma, con una relación 87Sr/86Sr inicial cercana a 0,7041, lo que apunta a una fuente del manto sublitosférico o la base de la corteza inferior. Estas rocas pertenecen a la clase A1 de granitos de tipo A, sugiriendo un origen relacionado a rifting o a puntos calientes, y sus relaciones de elementos trazas muestran afinidades con fundidos relacionados a basaltos de islas oceánicas. En este sentido son diferentes de todos los granitos de tipo A post-devónicos descriptos en Sierras Pampeanas Orientales.

  17. Nutrient and mercury deposition and storage in an alpine snowpack of the Sierra Nevada, USA

    Directory of Open Access Journals (Sweden)

    C. Pearson

    2015-01-01

    Full Text Available Bi-weekly snowpack core samples were collected at seven sites along two elevation gradients in the Tahoe Basin during two consecutive snow years to evaluate total wintertime snowpack accumulation of nutrients and pollutants in a high elevation watershed of the Sierra Nevada. Additional sampling of wet deposition and detailed snow pit profiles was conducted the following year to compare wet deposition to snowpack storage and assess the vertical dynamics of snowpack chemicals. Results show that on average organic N comprised 48% of all snowpack N, while nitrate (NO3--N and TAN (total ammonia nitrogen made up 25 and 27%, respectively. Snowpack NO3--N concentrations were relatively uniform across sampling sites over the sampling seasons and showed little difference between seasonal wet deposition and integrated snow pit concentrations in agreement with previous studies that identify wet deposition as the dominant source of wintertime NO3--N deposition. However, vertical snow pit profiles showed highly variable concentrations of NO3--N within the snowpack indicative of additional deposition and in snowpack dynamics. Unlike NO3--N, snowpack TAN doubled towards the end of winter and in addition to wet deposition, had a strong dry deposition component. Organic N concentrations in snowpack were highly variable (from 35 to 70% and showed no clear temporal or spatial dependence throughout the season. Integrated snowpack organic N concentrations were up to 2.5 times higher than seasonal wet deposition, likely due to microbial immobilization of inorganic N as evident by coinciding increases of organic N and decreases of inorganic N, in deeper, aged snowpack. Spatial and temporal deposition patterns of snowpack P were consistent with particulate-bound dry deposition inputs and strong impacts from in-basin sources causing up to 6 times enrichment at urban locations compared to remote sites. Snowpack Hg showed little temporal variability and was dominated by

  18. Impact of interannual variations in aerosol particle sources on orographic precipitation over California's Central Sierra Nevada

    Science.gov (United States)

    Creamean, J. M.; Ault, A. P.; White, A. B.; Neiman, P. J.; Ralph, F. M.; Minnis, P.; Prather, K. A.

    2015-01-01

    Aerosols that serve as cloud condensation nuclei (CCN) and ice nuclei (IN) have the potential to profoundly influence precipitation processes. Furthermore, changes in orographic precipitation have broad implications for reservoir storage and flood risks. As part of the CalWater field campaign (2009-2011), the variability and associated impacts of different aerosol sources on precipitation were investigated in the California Sierra Nevada using an aerosol time-of-flight mass spectrometer for precipitation chemistry, S-band profiling radar for precipitation classification, remote sensing measurements of cloud properties, and surface meteorological measurements. The composition of insoluble residues in precipitation samples collected at a surface site contained mostly local biomass burning and long-range transported dust and biological particles (2009), local sources of biomass burning and pollution (2010), and long-range transport from distant sources (2011). Although differences in the sources were observed from year-to-year, the most consistent source of dust and biological residues were associated with storms consisting of deep convective cloud systems with significant quantities of precipitation initiated in the ice phase. Further, biological residues were dominant (up to 40%) during storms with relatively warm cloud temperatures (up to -15 °C), supporting the important role bioparticles can play as ice nucleating particles. On the other hand, lower percentages of residues from local biomass burning and pollution were observed over the three winter seasons (on average 31 and 9%, respectively). When precipitation quantities were relatively low, these residues most likely served as CCN, forming smaller more numerous cloud droplets at the base of shallow cloud systems, and resulting in less efficient riming processes. The correlation between the source of aerosols within clouds and precipitation type and quantity will be further probed in models to understand the

  19. Early Neogene unroofing of the Sierra Nevada de Santa Marta along the Bucaramanga -Santa Marta Fault

    Science.gov (United States)

    Piraquive Bermúdez, Alejandro; Pinzón, Edna; Bernet, Matthias; Kammer, Andreas; Von Quadt, Albrecht; Sarmiento, Gustavo

    2016-04-01

    Plate interaction between Caribbean and Nazca plates with Southamerica gave rise to an intricate pattern of tectonic blocks in the Northandean realm. Among these microblocks the Sierra Nevada de Santa Marta (SNSM) represents a fault-bounded triangular massif composed of a representative crustal section of the Northandean margin, in which a Precambrian to Late Paleozoic metamorphic belt is overlain by a Triassic to Jurassic magmatic arc and collateral volcanic suites. Its western border fault belongs to the composite Bucaramanga - Santa Marta fault with a combined left lateral-normal displacement. SE of Santa Marta it exposes remnants of an Oligocene marginal basin, which attests to a first Cenoizoic activation of this crustal-scale lineament. The basin fill consists of a sequence of coarse-grained cobble-pebble conglomerates > 1000 m thick that unconformably overlay the Triassic-Jurassic magmatic arc. Its lower sequence is composed of interbedded siltstones; topwards the sequence becomes dominated by coarser fractions. These sedimentary sequences yields valuable information about exhumation and coeval sedimentation processes that affected the massif's western border since the Upper Eocene. In order to analyse uplifting processes associated with tectonics during early Neogene we performed detrital zircon U-Pb geochronology, detrital thermochronology of zircon and apatites coupled with the description of a stratigraphic section and its facies composition. We compared samples from the Aracataca basin with analog sequences found at an equivalent basin at the Oca Fault at the northern margin of the SNSM. Our results show that sediments of both basins were sourced from Precambrian gneisses, along with Mesozoic acid to intermediate plutons; sedimentation started in the Upper Eocene-Oligocene according to palynomorphs, subsequently in the Upper Oligocene a completion of Jurassic to Cretaceous sources was followed by an increase of Precambrian input that became the dominant

  20. Inexistence of permafrost at the top of the Veleta peak (Sierra Nevada)

    Science.gov (United States)

    Gómez-Ortiz, Antonio; Salvador-Franch, Ferran; Salvà-Catarineu, Montserrat; Oliva, Marc; Palacios, David; Tanarro, Luis Miguel; Schulte, Lothar

    2014-05-01

    Several deep drillings wew carried out along a latitudinal transect from Svalbard (78°N) to Sierra Nevada (37°N, Spain) within the project Permafrost and Climate Change in Europe (PACE). In this abstract we discuss the data corresponding to the drilling existing at the top of the Veleta peak, at an altitude of 3380 m. This drilling reach a depth of 114.5 m depth, although we analyze here the data of the first 60 m depth. UTL-1 loggers were installed at depths of 0.2, 0.6, 1.2, 2.6, 4, 7, 10, 13, 15, 20 and 60 m. The observation period spans from 2002 to 2013 with data being taken every 2 h. The most surficial loggersrecorded the largest annual temperature oscillations, reaching 22.6°C at 20 cm. Down to 10 m depth the annual temperature amplitude is still remarkable and seasonal temperature changes are even observed at depths of 15 to 20 m. Below this level the temperature remains constant. The logger installed at 60 m depth recorded small temperature changes between 2006 and 2009, oscillating between 2.38 and 2.61ºC. Since January 2010 the temperatures stabilized at 2.61°C. However, this slight temperature increase must be framed within the margin of instrumentation error of the devices. Data shows evidence of the inexistence ofpermanent negative temperatures at depth. In contrast to what happens in the nearby Veleta cirque floor (3100 m), where marginal permafrost conditions have been recorded, in the Veleta peak (3380 m) data points to the absence of a permafrost regime. This may be due to several factors: a) The existence of permafrost in the Veletacirque is directly related to the presence of fossil glacier ice corresponding to a glacier that existed there during the Little Ice Age. b ) The early melting of snow cover in the Veleta peak due to wind effect and incidence of solar radiation condition the absence of permafrost conditions at the summitin contrast to the Veleta cirquefloor, where the longer persistence of snow favours the presence of continuous