Science.gov

Sample records for zapla sierras subandinas

  1. Egg parasitoid of Saccharosydne subandina (Hemiptera: Delphacidae) in Neuquen, Argentina

    Saccharosydne subandina Remes Lenicov & Rossi Batiz is a recently described planthopper from Argentina which is known to feed on garlic, rye, and pampas grass (de Remes-Lenicov & Rossi-Batiz 2010). During a trip to Neuquén Province in February 2007, we noticed a heavy infestation of pampas grass, Co...

  2. Sierra Nevada Ecosystem Project

    C. I. Millar

    1996-01-01

    Sierra Nevada Ecosystems. The Sierra Nevada evokes images particular to each individual's experience of the range. These images take on the quality of immutability, and we expect to find the range basically unchanged from one year to the next. The Sierra Nevada, however, including its rocky foundations and the plants and animals that inhabit it, changes...

  3. Sierra Nevada Science Review

    Constance Millar; Amy Lind; Rowan Rowntree; Carl Skinner; Jared Verner; Bill Zielinski; Robert Ziemer

    1998-01-01

    In January, 1998, the Pacific Southwest Region and Pacific Southwest Research Station of the Forest Service initiated a collaborative effort to incorporate new information into planning future management of Sierra Nevada national forests. The project, known as the Sierra Nevada Framework for Conservation and Collaboration, will incorporate the latest scientific...

  4. Sierra Leone Estuary

    2014-02-05

    This image acquired by NASA Terra spacecraft is of the Sierra Leone estuary, which became a focal point for trade and interaction between Africans and Europeans because of its exceptional harbor, starting in the mid-15th century.

  5. Guide to Using Sierra

    SciT

    Shaw, Ryan Phillip; Agelastos, Anthony Michael; Miller, Joel D.

    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. Guide to Using Sierra

    SciT

    Shaw, Ryan Phillip; Agelastos, Anthony Michael; Miller, Joel D.

    2017-04-01

    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.

  7. Sierra University in Mexico

    ERIC Educational Resources Information Center

    Celis, Francisco Manuel Orozco

    2003-01-01

    Sierra University was designed to promote the development of the mountain communities in the State of Sonora, Mexico. The university offers high school graduates an opportunity to pursue their studies in their home region, in order to stimulate economic development and contribute to social cohesion in the highlands area. The university is equipped…

  8. Sierra Madre Oriental, Mexico

    NASA Technical Reports Server (NTRS)

    1985-01-01

    This view of the Sierra Madre Oriental, Mexico (26.5N, 102.0W) west of Monclova, shows a mining region of northern Mexico. Mine tailings can be seen on the mountain slopes and in the valley floor. In addition to mining activity, several irrigated agricultural areas supporting the local communities can be seen in the area.

  9. Status of the Sierra Nevada: the Sierra Nevada Ecosystem Project

    Erman, Don C.; ,

    1997-01-01

    The Sierra Nevada ecosystem project was requested by Congress in the Conference Report for Interior and related Agencies 1993 Appropriation Act, which authorized funds for a scientific review of the remaining old growth in the national forests of the Sierra Nevada in California, and for a study of the entire Sierra Nevada ecosystem by an independent panel of scientists, with expertise in diverse areas related to this issue. This CD-ROM is a digital version of the set of reports titled 'Sierra Nevada Ecosystem Project, final report to Congress' published in paper form by the Centers for Water and Wildland Resources of the University of California, Davis.

  10. Sierra Structural Dynamics Theory Manual

    SciT

    Reese, Garth M.

    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.more » 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.« less

  11. Fire in the Sierra Nevada

    Carl N. Skinner; Scott L. Stephens

    2004-01-01

    Fire has been described as both a major ecological force necessary for long-term functioning of Sierra Nevada ecosystems and as one of the greatest threats to human and natural resources (SNEP 1996a). Fire has shaped the terrestrial ecosystems of the Sierra Nevada for millennia. Before the mid-1800s, fires generally were frequent and mostly of low to moderate intensity...

  12. Biodiversity in the Sierra Nevada

    Dennis D. Murphy; Erica Fleishman; Peter A. Stine

    2004-01-01

    The earliest explorers of the Sierra Nevada hailed the mountain range for its unsurpassed scenery. Although a significant component of that beauty was an especially rich assemblage of plants and animals, it was not until many decades later that the Sierra Nevada's wealth of biodiversity was appreciated fully and documented in earnest. Indeed, by the time...

  13. SIERRA ANCHA WILDERNESS, ARIZONA.

    Wrucke, Chester T.; Light, Thomas D.

    1984-01-01

    Mineral surveys show that the Sierra Ancha Wilderness in Arizona has demonstrated resources of uranium, asbestos, and iron; probable and substantiated resource potential for uranium, asbestos, and iron; and a probable resource potential for fluorspar. Uranium resources occur in vein and strata-bound deposits in siltstone that underlies much of the wilderness. Deposits of long-staple chrysotile asbestos are likely in parts of the wilderness adjacent to known areas of asbestos production. Magnetite deposits in the wilderness form a small iron resource. No fossil fuel resources were identified in this study.

  14. Sierra Nevada, California

    1994-09-30

    STS068-267-097 (30 September-11 October 1994) --- An extensive view eastward from the irrigated San Joaquin Valley in the foreground, across the Sierra Nevada (living up to its name in early October), into the desert of eastern California and Nevada (which has no snow, despite the name). Mono Lake is just visible at the left edge of the frame; Owens Valley extends southward to Owens Lake, the next valley is Panamint Valley, and then Death Valley. Las Vegas and Lake Mead are visible at the upper right of the frame. The Space Radar Laboratory 2 (SRL-2) obtained extensive, multiple-pass data from many test sites within the region displayed, including Mammoth Mountain ski area south of Mono Lake, and in Death Valley.

  15. Sierra Structural Dynamics User's Notes

    SciT

    Reese, Garth M.

    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.

  16. Sierra/SD User's Notes.

    SciT

    Munday, Lynn Brendon; Day, David M.; Bunting, Gregory

    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.

  17. Modeling interfacial fracture in Sierra.

    SciT

    Brown, Arthur A.; Ohashi, Yuki; Lu, Wei-Yang

    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 conductedmore » 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.« less

  18. Susu Language Manual: Sierra Leone.

    ERIC Educational Resources Information Center

    Peace Corps, Freetown (Sierra Leone).

    A teacher's guide for Susu is designed for Peace Corps volunteer language instruction and geared to the daily language needs of volunteers in Sierra Leone. It contains a section on Susu phonology and 28 lessons on these topics: situation-specific greetings, basic greetings, introducing a friend, the market, travel and getting directions, visiting…

  19. My Great Migration from Sierra Leone

    ERIC Educational Resources Information Center

    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…

  20. Acting Administrator Lightfoot Visits Sierra Nevada Corporation

    2017-04-06

    Vice President, Space Exploration Systems (SES) at Sierra Nevada Corporation Steve Lindsey, left, speaks with acting NASA Administrator Robert Lightfoot, center, and acting NASA Deputy Administrator Lesa Roe, left, about the Dream Chaser Space System simulator, Thursday, April 6, 2017 during a visit to Sierra Nevada Corporation in Louisville, Colo. Photo Credit: (NASA/Joel Kowsky)

  1. Proceedings of the Sierra Nevada Science Symposium

    Dennis D. Murphy; Peter A. Stine

    2004-01-01

    Land and resource management issues in the Sierra Nevada are becoming increasingly complex and controversial. The objective of the Sierra Nevada Science Symposium was to provide a synoptic overview of the current state of scientific knowledge related to key management issues. Attempts were made to tie recent scientific findings to applications in land management and...

  2. Population education in Sierra Leone.

    PubMed

    Lucan, T A

    1985-06-01

    The 1977 Sierra Leone 3 year population education project had 5 objectives: 1) to develop a core of Sierra Leoneans qualified in population education, 2) to integrate population education concepts into the curriculum for secondary schools and teachers colleges, 3) to train teachers already engaged in trial teaching in pilot schools in the new integrated curricula to give support to their colleagues, 4) to integrate population education into the whole Sierra Leone educational system, and 5) to create an awareness of the implications of population growth on the socioeconomic development of the country. A 1977 seminar on the Social Studies and Population Education Program discussed population issues and economic and social development. The strategy recommended at the seminar was that both the minor and the major revision approaches be used in the integration of population education concepts into the existing curriculum of the National Program in Social Studies for the lower secondary level. A Spiral Curriculum was established in 1981 constructed of 6 topics: 1) man's origins, development, and characteristics; 2) man's environment; 3) man's culture; 4) population and resources; 5) communication in the service of man; and 6) global issues-achievement and problems. Both at in-service and at pre-servicetraining, the enquiry method of teaching was emphasized. By the end of December 1981, the curriculum in Social Studies integrated with Population Education was completed for secondary schools and secondary teachers' colleges. The availability of the textbooks that secondary school students will take to their homes for their parents to read will contribute immensely to the attainment of the development objective of creating an awareness of the implications and consequences of population growth on the socioeconomic development of the country.

  3. Cretin Memory Flow on Sierra

    SciT

    Langer, S. H.; Scott, H. A.

    2016-08-05

    The Cretin iCOE project has a goal of enabling the efficient generation of Non-LTE opacities for use in radiation-hydrodynamic simulation codes using the Nvidia boards on LLNL’s upcoming Sierra system. Achieving the desired level of accuracy for some simulations require the use of a vary large number of atomic configurations (a configuration includes the atomic level for all electrons and how they are coupled together). The NLTE rate matrix needs to be solved separately in each zone. Calculating NLTE opacities can consume more time than all other physics packages used in a simulation.

  4. AmeriFlux US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair

    SciT

    Goulden, Michael

    This is the AmeriFlux version of the carbon flux data for the site US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is a lodgepole pine subalpine woodland with no recent disturbance.

  5. Acting Administrator Lightfoot Visits Sierra Nevada Corporation

    2017-04-06

    Acting NASA Deputy Administrator Lesa Roe, left, and acting NASA Administrator Robert Lightfoot, right, listen as Alec Devereaux, a systems engineer with Sierra Nevada Corporation, right, discusses the Flight Control Integration Lab (FCIL), Thursday, April 6, 2017 during a visit to Sierra Nevada Corporation in Louisville, Colo. Sierra Nevada Corporation, with their Dream Chaser Cargo System, was one of three companies to be awarded Commercial Resupply Services (CRS-2) contracts designed to obtain cargo delivery services to the space station, disposal of unneeded cargo, and the return of research samples and other cargo from the station back to NASA. Photo Credit: (NASA/Joel Kowsky)

  6. Running Parallel Discrete Event Simulators on Sierra

    SciT

    Barnes, P. D.; Jefferson, D. R.

    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.

  7. Acting Administrator Lightfoot Visits Sierra Nevada Corporation

    2017-04-06

    Acting NASA Administrator Robert Lightfoot is seen as he flies the Dream Chaser Space System simulator, Thursday, April 6, 2017 during a visit to Sierra Nevada Corporation in Louisville, Colo. Photo Credit: (NASA/Joel Kowsky)

  8. Photo series for quantifying forest residues in the: sierra mixed conifer type, sierra true fir type.

    W.G. Maxwell; F.R. Ward

    1979-01-01

    Five series of photographs display different forest residue loading levels, by size classes, for areas of like timber type (Sierra mixed conifer and Sierra true fir) and cutting objective. Information with each photo includes measured weights, volumes and other residue data, information about the timber stand and harvest actions, and assessment of fire behavior and...

  9. Site fidelity of the declining amphibian Rana sierrae (Sierra Nevada yellow-legged frog)

    Kathleen Matthews; Haiganoush Preisler

    2010-01-01

    From 1997 to 2006, we used mark–recapture models to estimate the site fidelity of 1250 Sierra Nevada yellow-legged frogs (Rana sierrae) in Kings Canyon National Park, California, USA, during their three main activity periods of overwintering, breeding, and feeding. To quantify site fidelity, the tendency to return to and reuse previously occupied...

  10. Sierra/SolidMechanics 4.48 Goodyear Specific.

    SciT

    Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

    This document covers Sierra/SolidMechanics capabilities specific to Goodyear use cases. Some information may be duplicated directly from the Sierra/SolidMechanics User's Guide but is reproduced here to provide context for Goodyear-specific options.

  11. Sierra/SolidMechanics 4.46 Example Problems Manual.

    SciT

    Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

    Presented in this document are tests that exist in the Sierra/SolidMechanics example problem suite, which is a subset of the Sierra/SM regression and performance test suite. These examples showcase common and advanced code capabilities. A wide variety of other regression and verification tests exist in the Sierra/SM test suite that are not included in this manual.

  12. War and deforestation in Sierra Leone

    NASA Astrophysics Data System (ADS)

    Burgess, Robin; Miguel, Edward; Stanton, Charlotte

    2015-09-01

    The impact of armed conflict on the environment is of major public policy importance. We use a geographically disaggregated dataset of civil war violence together with satellite imagery of land cover to test whether war facilitated or prevented forest loss in Sierra Leone. The conflict data set allows us to establish where rebel groups were stationed and where battles and attacks occurred. The satellite data enables to us to monitor the change in forest cover (total, primary, and secondary) in all of Sierra Leone’s 151 chiefdoms, between 1990 (prior to the war) and 2000 (just prior to its end). The results suggest that conflict in Sierra Leone acted as a brake on local deforestation: conflict-ridden areas experienced significantly less forest loss relative to their more conflict-free counterparts.

  13. Acting Administrator Lightfoot Visits Sierra Nevada Corporation

    2017-04-06

    Associate administrator of NASA's Office of International and Interagency Relations Al Condes, left, acting NASA Deputy Administrator Lesa Roe, second from left, and acting NASA Administrator Robert Lightfoot, center, listen as Jude Vrazel, a senior systems engineer at Sierra Nevada Corporation, right, discusses the Vehicle Avionics Integration Lab (VAIL), Thursday, April 6, 2017 during a visit to Sierra Nevada Corporation in Louisville, Colo. Sierra Nevada Corporation, with their Dream Chaser Cargo System, was one of three companies to be awarded Commercial Resupply Services (CRS-2) contracts designed to obtain cargo delivery services to the space station, disposal of unneeded cargo, and the return of research samples and other cargo from the station back to NASA. Photo Credit: (NASA/Joel Kowsky)

  14. GPS Imaging of Sierra Nevada Uplift

    NASA Astrophysics Data System (ADS)

    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.

  15. Sierra/Solid Mechanics 4.48 User's Guide.

    SciT

    Merewether, Mark Thomas; Crane, Nathan K; de Frias, Gabriel Jose

    Sierra/SolidMechanics (Sierra/SM) is a Lagrangian, three-dimensional code for finite element analysis of solids and structures. It provides capabilities for explicit dynamic, implicit quasistatic and dynamic analyses. The explicit dynamics capabilities allow for the efficient and robust solution of models with extensive contact 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 a large library of material models. The code is written for parallel computing environments enabling scalable solutionsmore » of extremely large problems for both implicit and explicit analyses. It is built on the SIERRA Framework, which facilitates coupling with other SIERRA mechanics codes. This document describes the functionality and input syntax for Sierra/SM.« less

  16. Geologic map of the South Sierra Wilderness and South Sierra Roadless area, southern Sierra Nevada, California

    SciT

    Diggles, M.F.; Carter, K.E.

    1993-04-01

    The study area is underlain predominantly by granitoid rocks of the Sierra Nevada batholith. Metamorphic rocks are present in roof pendants mainly in the southwest corner of the study area and consist of quartz-biotite schist, phyllite, quartzite, marble, calc-silicate hornfels, and meta-dacite. Among the seven Triassic and (or) Jurassic plutons are three newly described units that consist of the gabbro of Deer Mountain, the tonalite of Falls Creek, and the quartz diorite of Round Mountain. The map shows one newly described unit that intrudes Triassic rocks: the granodiorite of Monache Creek which is a leucocratic, medium-grained, equi-granular, locally porphyritic biotitemore » hornblende granodiorite. Among the seven Cretaceous plutons are two newly described units. The Cretaceous rocks are generally medium- to coarse-grained, potassium-feldspar porphyritic granite with biotite and minor hornblende; it includes abundant pods of alaskite. The granite of Haiwee Creek is similar but only locally potassium-feldspar porphyritic and with only minor hornblende. Major-element data plotted on Harker diagrams show the older rocks to be higher in iron and magnesium and lower in silica than the younger rocks. There are abundant local pods of alaskite throughout the study area that consist of medium- to coarse-grained, leucocratic granite, alkali-feldspar granite and associated aplite and pegmatite bodies occurring as small pods and highly leucocratic border phases of nearby plutons. Tertiary and Quaternary volcanic rock include the rhyolite of Monache Mountain and Quaternary surficial deposits: fan, stream-channel, colluvium, talus, meadow-filling, rock-glacier, and glacial-moraine deposits. Important structures include the Sierran front fault and a possible extensional feature along which Bacon (1978) suggests Monache Mountain erupted.« less

  17. The Cora: People of the Sierra Madre.

    ERIC Educational Resources Information Center

    Lane, Sarah; And Others

    This text explores an isolated and indigenous people who live in the Sierra Madre Occidental in Mexico. Isolation has allowed the Cora Indians to maintain their traditional customs to a much greater extent than many other groups of Native Americans. The historical and geographical contexts of the Cora are presented in this curriculum resource.…

  18. MISR Sees the Sierra Nevadas in Stereo

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These MISR images of the Sierra Nevada mountains near the California-Nevada border were acquired on August 12, 2000 during Terra orbit 3472. On the left is an image from the vertical-viewing (nadir) camera. On the right is a stereo 'anaglyph' created using the nadir and 45.6-degree forward-viewing cameras, providing a three-dimensional view of the scene when viewed with red/blue glasses. The red filter should be placed over your left eye. To facilitate the stereo viewing, the images have been oriented with north toward the left.

    Some prominent features are Mono Lake, in the center of the images; Walker Lake, to its left; and Lake Tahoe, near the lower left. This view of the Sierra Nevadas includes Yosemite, Kings Canyon, and Sequoia National Parks. Mount Whitney, the highest peak in the contiguous 48 states (elev. 14,495 feet), is visible near the righthand edge. Above it (to the east), the Owens Valley shows up prominently between the Sierra Nevada and Inyo ranges.

    Precipitation falling as rain or snow on the Sierras feeds numerous rivers flowing southwestward into the San Joaquin Valley. The abundant fields of this productive agricultural area can be seen along the lower right; a large number of reservoirs that supply water for crop irrigation are apparent in the western foothills of the Sierras. Urban areas in the valley appear as gray patches; among the California cities that are visible are Fresno, Merced, and Modesto.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  19. Sierra/SolidMechanics 4.48 Verification Tests Manual.

    SciT

    Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

    2018-03-01

    Presented in this document is a small portion of the tests that exist in the Sierra / SolidMechanics (Sierra / SM) verification test suite. Most of these tests are run nightly with the Sierra / SM code suite, and the results of the test are checked versus the correct analytical result. For each of the tests presented in this document, the test setup, a description of the analytic solution, and comparison of the Sierra / SM code results to the analytic solution is provided. Mesh convergence is also checked on a nightly basis for several of these tests. This documentmore » can be used to confirm that a given code capability is verified or referenced as a compilation of example problems. Additional example problems are provided in the Sierra / SM Example Problems Manual. Note, many other verification tests exist in the Sierra / SM test suite, but have not yet been included in this manual.« less

  20. Sierra/SolidMechanics 4.48 Verification Tests Manual.

    SciT

    Plews, Julia A.; Crane, Nathan K.; de Frias, Gabriel Jose

    Presented in this document is a small portion of the tests that exist in the Sierra / SolidMechanics (Sierra / SM) verification test suite. Most of these tests are run nightly with the Sierra / SM code suite, and the results of the test are checked versus the correct analytical result. For each of the tests presented in this document, the test setup, a description of the analytic solution, and comparison of the Sierra / SM code results to the analytic solution is provided. Mesh convergence is also checked on a nightly basis for several of these tests. This documentmore » can be used to confirm that a given code capability is verified or referenced as a compilation of example problems. Additional example problems are provided in the Sierra / SM Example Problems Manual. Note, many other verification tests exist in the Sierra / SM test suite, but have not yet been included in this manual.« less

  1. Groundwater quality in the Sierra Nevada, California

    Fram, Miranda S.; Belitz, Kenneth

    2014-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project (PBP) of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Sierra Nevada Regional study unit constitutes one of the study units being evaluated.

  2. Undiagnosed Acute Viral Febrile Illnesses, Sierra Leone

    DTIC Science & Technology

    2014-07-01

    Sierra Leone in West Africa is in a Lassa fever – hyperendemic region that also includes Guinea and Li- beria. Each year...suspected Lassa fever cases result in submission of ≈500–700 samples to the Kenema Govern- ment Hospital Lassa Diagnostic Laboratory in eastern Si- erra...patients have acute diseases of unknown origin. To investigate what other ar- thropod-borne and hemorrhagic fever viral diseases might cause serious

  3. Sierra Madre Oriental in Coahuila, Mexico

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This desolate landscape is part of the Sierra Madre Oriental mountain range, on the border between the Coahuila and Nuevo Leon provinces of Mexico. This image was acquired by Landsat 7's Enhanced Thematic Mapper plus (ETM+) sensor on November 28, 1999. This is a false-color composite image made using shortwave infrared, infrared, and green wavelengths. The image has also been sharpened using the sensor's panchromatic band. Image provided by the USGS EROS Data Center Satellite Systems Branch

  4. Implementing an Ebola Vaccine Study - Sierra Leone.

    PubMed

    Widdowson, Marc-Alain; Schrag, Stephanie J; Carter, Rosalind J; Carr, Wendy; Legardy-Williams, Jennifer; Gibson, Laura; Lisk, Durodami R; Jalloh, Mohamed I; Bash-Taqi, Donald A; Kargbo, Samuel A Sheku; Idriss, Ayesha; Deen, Gibrilla F; Russell, James B W; McDonald, Wendi; Albert, Alison P; Basket, Michelle; Callis, Amy; Carter, Victoria M; Ogunsanya, Kelli R Clifton; Gee, Julianne; Pinner, Robert; Mahon, Barbara E; Goldstein, Susan T; Seward, Jane F; Samai, Mohamed; Schuchat, Anne

    2016-07-08

    In October 2014, the College of Medicine and Allied Health Sciences of the University of Sierra Leone, the Sierra Leone Ministry of Health and Sanitation, and CDC joined the global effort to accelerate assessment and availability of candidate Ebola vaccines and began planning for the Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE). STRIVE was an individually randomized controlled phase II/III trial to evaluate efficacy, immunogenicity, and safety of the recombinant vesicular stomatitis virus Ebola vaccine (rVSV-ZEBOV). The study population was health care and frontline workers in select chiefdoms of the five most affected districts in Sierra Leone. Participants were randomized to receive a single intramuscular dose of rVSV-ZEBOV at enrollment or to receive a single intramuscular dose 18-24 weeks after enrollment. All participants were followed up monthly until 6 months after vaccination. Two substudies separately assessed detailed reactogenicity over 1 month and immunogenicity over 12 months. During the 5 months before the trial, STRIVE and partners built a research platform in Sierra Leone comprising participant follow-up sites, cold chain, reliable power supply, and vaccination clinics and hired and trained at least 350 national staff. Wide-ranging community outreach, informational sessions, and messaging were conducted before and during the trial to ensure full communication to the population of the study area regarding procedures and current knowledge about the trial vaccine. During April 9-August 15, 2015, STRIVE enrolled 8,673 participants, of whom 453 and 539 were also enrolled in the safety and immunogenicity substudies, respectively. As of April 28, 2016, no Ebola cases and no vaccine-related serious adverse events, which by regulatory definition include death, life-threatening illness, hospitalization or prolongation of hospitalization, or permanent disability, were reported in the study population. Although STRIVE will not produce an

  5. Invasive exotic plant species in Sierra Nevada ecosystems

    Carla M. D' Antonio; Eric L. Berlow; Karen L. Haubensak

    2004-01-01

    The Sierra Nevada is a topographically and floristically diverse region of the western United States. While it comprises only a fifth of the total land area of California, half of the native plant species in the state occur within the range. In addition, more than 400 plant species are endemic to the Sierra Nevada and many of these are listed as threatened or have...

  6. Biosphere and atmosphere interactions in Sierra Nevada forests

    Allen H. Goldstein

    2004-01-01

    In the Sierra Nevada, studies are being conducted to assess the impacts of both anthropogenic and biogenic hydrocarbon emissions on regional tropospheric ozone and fine aerosol production. Impacts of ozone deposition and management practices on ecosystem health are also being studied. Human-induced changes in regional air quality have consequences for Sierra Nevada...

  7. Inventory of Commercial Hardwoods in the High Sierra

    Norman H. Pillsbury; George L. McCaskill

    1991-01-01

    A hardwood resources assessment was completed for the Sierra Economic Development District in the north central Sierra Nevada. The assessment included the development of a tree grading system for the major hardwood species in the area, an inventory of the hardwood resources, and recommendations for hardwood management. Hardwood volumes of total wood available for...

  8. Research Brief: Impacts of Extreme Fires in the Sierra Nevada

    Jonathan Long

    2014-01-01

    Scientists from PSW considered the effects of severe wildfire in the Sierra Nevada and southern Cascade Range in a recent synthesis that focused on promoting resiliency of forests and the societies connected to them. Fire is indispensable to maintaining the health and productivity of most forests in the Sierra Nevada, and fires can also rejuvenate aquatic systems by...

  9. Micrometeorological Observations in a Sierra Nevada Meadow

    NASA Astrophysics Data System (ADS)

    Blackburn, D. A.; Oliphant, A. J.

    2016-12-01

    Mountain meadows play important roles on watershed and ecosystem services, including improving water quality, moderating runoff and providing biodiversity hotspots. In the Sierra Nevada, mountain meadows are an integral part of the mountain ecosystem and watersheds that impact more than 20 million people. Grazing, logging and other forms of anthropogenic land use in the Sierra Nevada have degraded the functioning of meadows, by altering the morphology, hydrology and vegetation. Existing meandering stream networks become incised and straightened by increased runoff, which effectively lowers the water table and completely alters the ecosystem from moist meadow sedges, grasses, and herbs to dryland grass and shrubs. Given the large growth cycle in healthy meadows, it is also expected that they sequester a significant amount of carbon and enhance atmospheric humidity through evapotranspiration, but relatively little work has been done on the bio-micrometeorology of meadows. The purpose of this study is to assess the growing season carbon, water and energy budgets of a partly degraded meadow in the northern Sierra Nevada. Loney Meadow, located at nearly 2,000 m in the Tahoe National Forest, has been identified as a degraded meadow and is scheduled to undergo restoration work to raise the water table in 2017. A micrometeorological tower with eddy covariance instruments was deployed at the site for most of the snow-free period from May to October 2016. The measurements include: fluxes of CO2, water vapor, surface radiation and energy budget components; ancillary meteorological and soil data; and an automated camera capturing daily images of the meadow surface. The poster will present diurnal and seasonal CO2 on a daily basis with a very rapid increase at the onset of the growing season.

  10. Undiagnosed Acute Viral Febrile Illnesses, Sierra Leone

    PubMed Central

    Rossi, Cynthia A.; Khan, Sheik H.; Goba, Augustine; Fair, Joseph N.

    2014-01-01

    Sierra Leone in West Africa is in a Lassa fever–hyperendemic region that also includes Guinea and Liberia. Each year, suspected Lassa fever cases result in submission of ≈500–700 samples to the Kenema Government Hospital Lassa Diagnostic Laboratory in eastern Sierra Leone. Generally only 30%–40% of samples tested are positive for Lassa virus (LASV) antigen and/or LASV-specific IgM; thus, 60%–70% of these patients have acute diseases of unknown origin. To investigate what other arthropod-borne and hemorrhagic fever viral diseases might cause serious illness in this region and mimic Lassa fever, we tested patient serum samples that were negative for malaria parasites and LASV. Using IgM-capture ELISAs, we evaluated samples for antibodies to arthropod-borne and other hemorrhagic fever viruses. Approximately 25% of LASV-negative patients had IgM to dengue, West Nile, yellow fever, Rift Valley fever, chikungunya, Ebola, and Marburg viruses but not to Crimean-Congo hemorrhagic fever virus. PMID:24959946

  11. Grizzly Valley fault system, Sierra Valley, CA

    Gold, Ryan; Stephenson, William; Odum, Jack; Briggs, Rich; Crone, Anthony; Angster, Steve

    2012-01-01

    The Grizzly Valley fault system (GVFS) strikes northwestward across Sierra Valley, California and is part of a network of active, dextral strike-slip faults in the northern Walker Lane (Figure 1). To investigate Quaternary motion across the GVFS, we analyzed high-resolution (0.25 m) airborne LiDAR data (Figure 2) in combination with six, high-resolution, P-wave, seismic-reflection profiles [Gold and others, 2012]. The 0.5- to 2.0-km-long seismic-reflection profiles were sited orthogonal to suspected tectonic lineaments identified from previous mapping and our analysis of airborne LiDAR data. To image the upper 400–700 m of subsurface stratigraphy of Sierra Valley (Figure 3), we used a 230-kg accelerated weight drop source. Geophone spacing ranged from 2 to 5 m and shots were co-located with the geophones. The profiles reveal a highly reflective, deformed basal marker that we interpret to be the top of Tertiary volcanic rocks, overlain by a 120- to 300-m-thick suite of subhorizontal reflectors we interpret as Plio-Pleistocene lacustrine deposits. Three profiles image the principle active trace of the GVFS, which is a steeply dipping fault zone that offsets the volcanic rocks and the basin fill (Figures 4 & 5).

  12. NASA Deputy Administrator Tours Sierra Nevada Space Systems' Dre

    2011-02-05

    Director of Advanced Programs, Sierra Nevada Corporation, Jim Voss talks during a press conference with Sierra Nevada's Dream Chaser spacecraft in the background on Saturday, Feb. 5, 2011, at the University of Colorado at Boulder. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  13. NASA Deputy Administrator Tours Sierra Nevada Space Systems' Dre

    2011-02-05

    Sierra Nevada Space Systems chairman Mark Sirangello talks during a press conference with Sierra Nevada's Dream Chaser spacecraft in the background on Saturday, Feb. 5, 2011, at the University of Colorado at Boulder. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  14. Projected Treatment Capacity Needs in Sierra Leone

    PubMed Central

    White, Richard A; MacDonald, Emily; de Blasio, Birgitte Freiesleben; Nygård, Karin; Vold, Line; Røttingen, John-Arne

    2015-01-01

    Background: The ongoing outbreak of Ebola Virus Disease in West Africa requires immediate and sustained input from the international community in order to curb transmission. The CDC has produced a model that indicates that to end the outbreak by pushing the reproductive number below one, 25% of the patients must be placed in an Ebola Treatment Unit (ETC) and 45% must be isolated in community settings in which risk of disease transmission is reduced and safe burials are provided. In order to provide firmer targets for the international response in Sierra Leone, we estimated the national and international personnel and treatment capacity that may be required to reach these percentages. Methods: We developed a compartmental SEIR model that was fitted to WHO data and local data allowing the reproductive number to change every 8 weeks to forecast the progression of the EVD epidemic in Sierra Leone. We used the previously estimated 2.5x correction factor estimated by the CDC to correct for underreporting. Number of personnel required to provide treatment for the predicted number of cases was estimated using UNMEER and UN OCHA requests for resources required to meet the CDC target of 70% isolation. Results: As of today (2014-12-04), we estimate that there are 810 (95% CI=646 to 973) EVD active cases in treatment, with an additional 3751 (95% CI=2778 to 4723) EVD cases unreported and untreated. To reach the CDC targets today, we need 1140 (95% CI=894 to 1387) cases in ETCs and 2052 (95% CI=1608 to 2496) at home or in a community setting with a reduced risk for disease transmission. In 28 days (2015-01-01), we will need 1309 (95% CI=804 to 1814) EVD cases in ETCs and 2356 (95% CI=1447 to 3266) EVD cases at reduced risk of transmission. If the current transmission rate is not reduced, up to 3183 personnel in total will be required in 56 days (2015-01-29) to operate ETCs according to our model. Conclusions: The current outbreak will require massive input from the

  15. Projected treatment capacity needs in sierra leone.

    PubMed

    White, Richard A; MacDonald, Emily; de Blasio, Birgitte Freiesleben; Nygård, Karin; Vold, Line; Røttingen, John-Arne

    2015-01-30

    The ongoing outbreak of Ebola Virus Disease in West Africa requires immediate and sustained input from the international community in order to curb transmission. The CDC has produced a model that indicates that to end the outbreak by pushing the reproductive number below one, 25% of the patients must be placed in an Ebola Treatment Unit (ETC) and 45% must be isolated in community settings in which risk of disease transmission is reduced and safe burials are provided. In order to provide firmer targets for the international response in Sierra Leone, we estimated the national and international personnel and treatment capacity that may be required to reach these percentages. We developed a compartmental SEIR model that was fitted to WHO data and local data allowing the reproductive number to change every 8 weeks to forecast the progression of the EVD epidemic in Sierra Leone. We used the previously estimated 2.5x correction factor estimated by the CDC to correct for underreporting. Number of personnel required to provide treatment for the predicted number of cases was estimated using UNMEER and UN OCHA requests for resources required to meet the CDC target of 70% isolation. As of today (2014-12-04), we estimate that there are 810 (95% CI=646 to 973) EVD active cases in treatment, with an additional 3751 (95% CI=2778 to 4723) EVD cases unreported and untreated. To reach the CDC targets today, we need 1140 (95% CI=894 to 1387) cases in ETCs and 2052 (95% CI=1608 to 2496) at home or in a community setting with a reduced risk for disease transmission. In 28 days (2015-01-01), we will need 1309 (95% CI=804 to 1814) EVD cases in ETCs and 2356 (95% CI=1447 to 3266) EVD cases at reduced risk of transmission. If the current transmission rate is not reduced, up to 3183 personnel in total will be required in 56 days (2015-01-29) to operate ETCs according to our model. The current outbreak will require massive input from the international community in order to curb the

  16. AmeriFlux US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle

    SciT

    Goulden, Michael

    This is the AmeriFlux version of the carbon flux data for the site US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is an oak/pine forest, with occasional thinning and wildfire, a prescribed understory burn ~2012, and severe drought and ~80% canopy mortality in 2011-15

  17. AmeriFlux US-CZ3 Sierra Critical Zone, Sierra Transect, Sierran Mixed Conifer, P301

    SciT

    Goulden, Michael

    This is the AmeriFlux version of the carbon flux data for the site US-CZ3 Sierra Critical Zone, Sierra Transect, Sierran Mixed Conifer, P301. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is a pine/fir forest; it historically experienced logging and wildfire, was thinned in ~2012, and experienced severe drought and ~20% canopy mortality in 2011-15.

  18. The Children's War: Towards Peace in Sierra Leone. A Field Report Assessing the Protection and Assistance Needs of Sierra Leonean Children and Adolescents.

    ERIC Educational Resources Information Center

    Sommers, Marc

    Based on a 3-week field visit to Sierra Leone and Guinea, this report investigates why children (ages 0-17) have become key figures in Sierra Leone's civil war, and explores the problems that war has caused them. The report describes significant new effects of violence on three groups of Sierra Leonean children, very few of whom have received any…

  19. Interaction of an Introduced Predator with Future Effects of Climate Change in the Recruitment Dynamics of the Imperiled Sierra Nevada Yellow-legged Frog (Rana sierrae)

    I Lacan; Kathleen R. Matthews; K.V. Feldman

    2008-01-01

    Between-year variation in snowpack (from 20 to 200% of average) and summer rainfall cause large fluctuations in volume of small lakes in the higher elevation (> 3000 m) Sierra Nevada, which are important habitat for the imperiled Sierra Nevada Yellow-legged Frog, Rana sierrae. Climate change (global warming) is predicted to increase these...

  20. Geomagnetic Polarity Epochs: Sierra Nevada II.

    PubMed

    Cox, A; Doell, R R; Dalrymple, G B

    1963-10-18

    Ten new determinations on volcanic extrusions in the Sierra Nevada with potassium-argon ages of 3.1 million years or less indicate that the remanent magnetizations fall into two groups, a normal group in which the remanent magnetization is directed downward and to the north, and a reversed group magnetized up and to the south. Thermomagnetic experiments and mineralogic studies fail to provide an explanation of the opposing polarities in terms of mineralogic control, but rather suggest that the remanent magnetization reflects reversals of the main dipole field of the earth. All available radiometric ages are consistent with this field-reversal hypothesis and indicate that the present normal polarity epoch (N1) as well as the previous reversed epoch (R1) are 0.9 to 1.0 million years long, whereas the previous normal epoch (N2) was at least 25 percent longer.

  1. Geomagnetic polarity epochs: Sierra Nevada II

    Cox, A.; Doell, Richard R.; Brent, Dalrymple G.

    1963-01-01

    Ten new determinations on volcanic extrusions in the Sierra Nevada with potassium-argon ages of 3.1 million years or less indicate that the remanent magnetizations fall into two groups, a normal group in which the remanent magnetization is directed downward and to the north, and a reversed group magnetized up and to the south. Thermomagnetic experiments and mineralogic studies fail to provide an explanation of the opposing polarities in terms of mineralogic control, but rather suggest that the remanent magnetization reflects reversals of the main dipole field of the earth. All available radiometric ages are consistent with this field-reversal hypothesis and indicate that the present normal polarity epoch (N1) as well as the previous reversed epoch (R1) are 0.9 to 1.0 million years long, whereas the previous normal epoch (N2) was at least 25 percent longer.

  2. Sierra Toolkit Manual Version 4.48.

    SciT

    Sierra Toolkit Team

    This report provides documentation for the SIERRA Toolkit (STK) modules. STK modules are intended to provide infrastructure that assists the development of computational engineering soft- ware such as finite-element analysis applications. STK includes modules for unstructured-mesh data structures, reading/writing mesh files, geometric proximity search, and various utilities. This document contains a chapter for each module, and each chapter contains overview descriptions and usage examples. Usage examples are primarily code listings which are generated from working test programs that are included in the STK code-base. A goal of this approach is to ensure that the usage examples will not fall outmore » of date. This page intentionally left blank.« less

  3. 75 FR 17896 - Sierra County, CA, Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ... issues relating to implementing the Secure Rural Schools and Community Self-Determination Act of 2000... National Forest System lands on the Humboldt- Toiyabe, Plumas and Tahoe National Forests in Sierra County...

  4. 75 FR 22100 - Sierra County, CA, Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... issues relating to implementing the Secure Rural Schools and Community Self Determination Act of 2000... National Forest System lands on the Humboldt-Toiyabe, Plumas and Tahoe National Forests in Sierra County...

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

    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.

  6. 75 FR 56980 - Sierra County Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... Committee Act. The purpose of the meeting is to discuss projects submitted for funding and the expenditure of Title II funds benefiting National Forest System lands in Sierra County. DATES: The meeting will...

  7. Initiatives for Sustainable Community Development in Sierra Leone.

    ERIC Educational Resources Information Center

    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)

  8. NASA Deputy Administrator Tours Sierra Nevada Space Systems

    2011-02-05

    Sierra Nevada Space Systems chairman Mark Sirangello talks to NASA Deputy Administrator Lori Garver, on Saturday, Feb. 5, 2011, in Louisville, Colo. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  9. NASA Deputy Administrator Tours Sierra Nevada Space Systems

    2011-02-05

    NASA Deputy Administrator Lori Garver speaks at Sierra Nevada Space Systems, on Saturday, Feb. 5, 2011, in Louisville, Colo. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  10. NASA Deputy Administrator Tours Sierra Nevada Space Systems' Dre

    2011-02-05

    Sierra Nevada's Dream Chaser spacecraft is seen as NASA Deputy Administrator Lori Garver talks during a press conference on Saturday, Feb. 5, 2011, at the University of Colorado at Boulder. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  11. Sierra/SolidMechanics 4.48 Capabilities in Development.

    SciT

    Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

    This document is a user's guide for capabilities that are not considered mature but are available in Sierra/SolidMechanics (Sierra/SM) for early adopters. The determination of maturity of a capability is determined by many aspects: having regression and verification level testing, documentation of functionality and syntax, and usability are such considerations. Capabilities in this document are lacking in one or many of these aspects.

  12. Preliminary flora of the Sierra Bacadehuachi, Sonora, Mexico

    Thomas R. Van Devender; Ana Lilia Reina-Guerrero; George M. Ferguson; George Yatskievych; Beatriz E. Loyola-Reina; Gertrudis Yanes-Arvayo; Maria de la Paz Montanez-Armenta; John L. Anderson; Stephen F. Hale; Sky Jacobs

    2013-01-01

    The Sierra Bacadéhuachi in east-central Sonora is the westernmost mountain range in the Sierra Madre Occidental (SMO), located east of Bacadéhuachi, Municipio de Bacadéhuachi, 34 km east of the Chihuahua border, and 165 km south of the Arizona border. The vegetation ranges from lowland foothills thornscrub up through desert grassland to oak woodland and pine-oak forest...

  13. Phylogeography and historical demography of the Pacific Sierra mackerel (Scomberomorus sierra) in the Eastern Pacific

    PubMed Central

    2010-01-01

    Background Testing connectivity among populations of exploited marine fish is a main concern for the development of conservation strategies. Even though marine species are often considered to display low levels of population structure, barriers to dispersal found in the marine realm may restrict gene flow and cause genetic divergence of populations. The Pacific Sierra mackerel (Scomberomorus sierra) is a pelagic fish species distributed throughout the tropical and subtropical waters of the eastern Pacific. Seasonal spawning in different areas across the species range, as well as a limited dispersal, may result in a population genetic structure. Identification of genetically discrete units is important in the proper conservation of the fishery. Results Samples collected from the Eastern Pacific, including the areas of main abundance of the species, presented high levels of mtDNA genetic diversity and a highly significant divergence. At least two genetically discrete groups were detected in the northern (Sinaloa) and central areas (Oaxaca and Chiapas) of the species range, exhibiting slight genetic differences with respect to the samples collected in the southern region (Peru), together with a "chaotic genetic patchiness" pattern of differentiation and no evidence of isolation by distance. Historical demographic parameters supported the occurrence of past population expansions, whereas the divergence times between populations coincided with the occurrence of glacial maxima some 220 000 years ago. Conclusions The population genetic structure detected for the Pacific Sierra mackerel is associated with a limited dispersal between the main abundance areas that are usually linked to the spawning sites of the species. Population expansions have coincided with glacial-interglacial episodes in the Pleistocene, but they may also be related to the increase in the SST and with upwelling areas in the EEP since the early Pleistocene. PMID:20438637

  14. Contaminant studies in the Sierra Nevadas

    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

  15. Snowmelt discharge characteristics Sierra Nevada, California

    Peterson, David; Smith, Richard; Stewart, Iris; Knowles, Noah; Soulard, Chris; Hager, Stephen

    2005-01-01

    Alpine snow is an important water resource in California and the western U.S. Three major features of alpine snowmelt are the spring pulse (the first surge in snowmelt-driven river discharge in spring), maximum snowmelt discharge, and base flow (low river discharge supported by groundwater in fall). A long term data set of hydrologic measurements at 24 gage locations in 20 watersheds in the Sierra Nevada was investigated to relate patterns of snowmelt with stream discharge In wet years, the daily variations in snowmelt discharge at all the gage locations in the Sierra Nevada correlate strongly with the centrally located Merced River at Happy Isles, Yosemite National Park (i.e., in 1983, the mean of the 23 correlations was R= 0.93 + 0.09) ; in dry years, however, this correlation breaks down (i.e., in year 1977, R=0.72 + 0.24). A general trend towards earlier snowmelt was found and modeled using correlations with the timing of the spring pulse and the river discharge center of mass. For the 24 river and creek gage locations in this study, the spring pulse appeared to be a more sensitive measure of early snowmelt than the center of mass. The amplitude of maximum daily snowmelt discharge correlates strongly with initial snow water equivalent. Geologic factors, base rock permeability and soil-to-bedrock ratio, influence snowmelt flow pathways. Although both surface and ground water flows and water levels increase in wet years compared to dry years, the increase was greater for surface water in a watershed with relatively impermeable base rock than for surface water in a watershed with highly permeable base rock The relation was the opposite for base flow (ground water). The increase was greater for groundwater in a watershed with permeable rock compared to ground water in a watershed with impermeable rock. A similar, but weaker, surface/groundwater partitioning was observed in relatively impermeable granitic watersheds with differing soil-to-bedrock ratios. The

  16. 76 FR 44535 - Revisions to the California State Implementation Plan, Northern Sierra Air Quality Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-26

    ... the California State Implementation Plan, Northern Sierra Air Quality Management District, Sacramento Metropolitan Air Quality Management District, and South Coast Air Quality Management District AGENCY... the Northern Sierra Air Quality Management District (NSAQMD), Sacramento Metropolitan Air Quality...

  17. 77 FR 23192 - Revisions to the California State Implementation Plan, Northern Sierra and Sacramento...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ... proposing to approve revisions to the Northern Sierra Air Quality Management District (NSAQMD) and Sacramento Metropolitan Air Quality Management District (SMAQMD) portions of the California State... the California State Implementation Plan, Northern Sierra and Sacramento Metropolitan Air Quality...

  18. 76 FR 44493 - Revisions to the California State Implementation Plan, Northern Sierra Air Quality Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-26

    ... California State Implementation Plan, Northern Sierra Air Quality Management District, Sacramento Metropolitan Air Quality Management District, and South Coast Air Quality Management District AGENCY... approve revisions to the Northern Sierra Air Quality Management District (NSAQMD), Sacramento Metropolitan...

  19. Post-Ebola Syndrome, Sierra Leone.

    PubMed

    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 (p<0.03). This complete survivor cohort from 1 ETU enables analysis of the proportion of symptoms of post-Ebola syndrome. The Ebola epidemic is waning, but the effects of the disease will remain.

  20. Adolescent fertility management: the Sierra Leone experience.

    PubMed

    Lamin, M M; Singleton, A

    1982-01-01

    Because of growing concerns for the problems of adolescent fertility, a training program in Adolescent Fertility Management was conducted in Sierra Leone in 1981. The program was designed to actuate the interdisciplinary energies necessary for exploring the depth of the problem and to develop strategies for possible solutions. 2 program activities were conducted: a Former Participant Conference, which resulted in the development of a draft of a country-wide program; and a 2-week training workshop. In order to create public awareness, the participants presented an original drama, a synopsis of which is provided. Solutions to the problems of adolescent fertility must address not only the availability and use of contraceptives, but also a reorientation of the attitudes of parents on sex education. The practice of expelling pregnant adolescents from educational institutions only serves to compound the problems. A list of the topics covered during the workshops is provided, as are a summary of the conclusions and subsequent recommendations. Participants voted to form a national organization whose main objective is the reduction of teenage pregnancy by at least 12% within a 12 month period through the creation of a national awareness campaign.

  1. Ebola Virus Disease--Sierra Leone and Guinea, August 2015.

    PubMed

    Hersey, Sara; Martel, Lise D; Jambai, Amara; Keita, Sakoba; Yoti, Zabulon; Meyer, Erika; Seeman, Sara; Bennett, Sarah; Ratto, Jeffrey; Morgan, Oliver; Akyeampong, Mame Afua; Sainvil, Schabbethai; Worrell, Mary Claire; Fitter, David; Arnold, Kathryn E

    2015-09-11

    The Ebola virus disease (Ebola) outbreak in West Africa began in late 2013 in Guinea (1) and spread unchecked during early 2014. By mid-2014, it had become the first Ebola epidemic ever documented. Transmission was occurring in multiple districts of Guinea, Liberia, and Sierra Leone, and for the first time, in capital cities (2). On August 8, 2014, the World Health Organization (WHO) declared the outbreak to be a Public Health Emergency of International Concern (3). Ministries of Health, with assistance from multinational collaborators, have reduced Ebola transmission, and the number of cases is now declining. While Liberia has not reported a case since July 12, 2015, transmission has continued in Guinea and Sierra Leone, although the numbers of cases reported are at the lowest point in a year. In August 2015, Guinea and Sierra Leone reported 10 and four confirmed cases, respectively, compared with a peak of 526 (Guinea) and 1,997 (Sierra Leone) in November 2014. This report details the current situation in Guinea and Sierra Leone, outlines strategies to interrupt transmission, and highlights the need to maintain public health response capacity and vigilance for new cases at this critical time to end the outbreak.

  2. The future of biodiversity in the Sierra Nevada through the Lake Tahoe Basin Looking Glass

    Patricia N. Manley

    2004-01-01

    The Sierra Nevada’s biological distinction and diversity are almost as legendary as its spectacular peaks and beautiful granite landscapes. The Sierra Nevada is recognized as a zoogeographic region on the basis of the coincidence of species ranges (for example, Udvardy 1969, 1975; Welsh 1994). Udvardy (1969) defined the Sierra Nevada bioregion as bounded by the Great...

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

    NASA Astrophysics Data System (ADS)

    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.

  4. Sierra Nevada Mountain Range as seen from STS-58

    1994-10-20

    STS058-72-004 (18 Oct-1 Nov 1993) --- The Sierra Nevada Mountain Range can be seen in this north-looking high oblique view taken in October, 1993, by the STS-58 crew. Visible in the view to the west of the Sierra Nevada are the San Joaquin and Sacramento Valleys of central California. The San Francisco/Oakland Bay Area can be seen to the west of the valley at the extreme left of the photograph. To the east or right of the Sierra Nevada, the basin and Range Region of central and northern Nevada is visible. Mono Lake, Lake Tahoe and Pyramid Lake are also visible in this scene. The long northwest/southeast trending Walker Lane Shear Zone, which lies just to the east (right) of the Sierra Nevada is also visible. Near the top of the view (near the horizon), the snow covered volcanic peak Mount Shasta can be seen. Over 645 kilometers (400 miles) long and from 65 to 130 kilometers (40 to 80 miles) wide, the Sierra Nevada have many peaks in excess of 3,300 meters (11,000 feet) above sea level. A titled fault block in structure (the largest in the United States) and shaped by glaciers during the last ice age over 12,000 years ago, the Sierra Nevada eastern front rises sharply from the Great Basin of Nevada, while its western slope descends gradually to the hills bordering the Central Valley of California. Snow-fed streams supply much of the irrigation water to the Central Valley and to western Nevada and also generate hydroelectricity. Recent above normal precipitation (snowfall) of the last two years has helped in alleviating the drought conditions that had prevailed throughout most of California in the mid and late 1980's and early 1990's.

  5. Ebola Surveillance - Guinea, Liberia, and Sierra Leone.

    PubMed

    McNamara, Lucy A; Schafer, Ilana J; Nolen, Leisha D; Gorina, Yelena; Redd, John T; Lo, Terrence; Ervin, Elizabeth; Henao, Olga; Dahl, Benjamin A; Morgan, Oliver; Hersey, Sara; Knust, Barbara

    2016-07-08

    Developing a surveillance system during a public health emergency is always challenging but is especially so in countries with limited public health infrastructure. Surveillance for Ebola virus disease (Ebola) in the West African countries heavily affected by Ebola (Guinea, Liberia, and Sierra Leone) faced numerous impediments, including insufficient numbers of trained staff, community reticence to report cases and contacts, limited information technology resources, limited telephone and Internet service, and overwhelming numbers of infected persons. Through the work of CDC and numerous partners, including the countries' ministries of health, the World Health Organization, and other government and nongovernment organizations, functional Ebola surveillance was established and maintained in these countries. CDC staff were heavily involved in implementing case-based surveillance systems, sustaining case surveillance and contact tracing, and interpreting surveillance data. In addition to helping the ministries of health and other partners understand and manage the epidemic, CDC's activities strengthened epidemiologic and data management capacity to improve routine surveillance in the countries affected, even after the Ebola epidemic ended, and enhanced local capacity to respond quickly to future public health emergencies. However, the many obstacles overcome during development of these Ebola surveillance systems highlight the need to have strong public health, surveillance, and information technology infrastructure in place before a public health emergency occurs. Intense, long-term focus on strengthening public health surveillance systems in developing countries, as described in the Global Health Security Agenda, is needed.The activities summarized in this report would not have been possible without collaboration with many U.S and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

  6. NASA Deputy Administrator Tours Sierra Nevada Space Systems' Dre

    2011-02-05

    NASA Deputy Administrator Lori Garver talks during a press conference with Sierra Nevada's Dream Chaser spacecraft in the background on Saturday, Feb. 5, 2011, at the University of Colorado at Boulder. Sierra Nevada's Dream Chaser spacecraft is under development with support from NASA's Commercial Crew Development Program to provide crew transportation to and from low Earth orbit. NASA is helping private companies develop innovative technologies to ensure that the U.S. remains competitive in future space endeavors. Photo Credit: (NASA/Bill Ingalls)

  7. Sierra/Aria 4.48 Verification Manual.

    SciT

    Sierra Thermal Fluid Development Team

    Presented in this document is a portion of the tests that exist in the Sierra Thermal/Fluids verification test suite. Each of these tests is run nightly with the Sierra/TF code suite and the results of the test checked under mesh refinement against the correct analytic result. For each of the tests presented in this document the test setup, derivation of the analytic solution, and comparison of the code results to the analytic solution is provided. This document can be used to confirm that a given code capability is verified or referenced as a compilation of example problems.

  8. Gravity and Magnetic Anomalies of the Sierra Madera, Texas, "Dome".

    PubMed

    Van Lopik, J R; Geyer, R A

    1963-10-04

    A geophysical traverse across the Sierra Madera "Dome" indicates a negative gravity anomaly of 1(1/2) milligals over the zone of brecciation in the center and a residual positive anomaly of (1/2) milligal associated with a positive magnetic anomaly of 25 x 10(-5) oersted to the southeast of the zone of brecciation. Areal surveys are needed before any definite conclusions can be drawn concerning the origin of Sierra Madera. However, gravity and magnetic data can be extremely valuable in establishing criteria for classifying terrestrial and lunar features according to meteoritic and cryptovolcanic origin.

  9. Comparison of preliminary herpetofaunas of the Sierras la Madera (Oposura) and Bacadehuachi with the mainland Sierra Madre Occidental in Sonora, Mexico

    Thomas R. Van Devender; Erik F. Enderson; Dale S. Turner; Roberto A. Villa; Stephen F. Hale; George M. Ferguson; Charles Hedgcock

    2013-01-01

    Amphibians and reptiles were observed in the Sierra La Madera (59 species), an isolated Sky Island mountain range, and the Sierra Bacadéhuachi (30 species), the westernmost mountain range in the Sierra Madre Occidental (SMO) range in east-central Sonora. These preliminary herpetofaunas were compared with the herpetofauna of the Yécora area in eastern Sonora in the main...

  10. Comparison of the tropical floras of the Sierra la Madera and the Sierra Madre Occidental, Sonora, Mexico

    Thomas R. Van Devender; Gertrudis Yanes-Arvayo; Ana Lilia Reina-Guerrero; Melissa Valenzuela-Yanez; Maria de la Paz Montanez-Armenta; Hugo Silva-Kurumiya

    2013-01-01

    The floras of the tropical vegetation in the Sky Island Sierra la Madera (SMA) near Moctezuma in northeastern Sonora (30°00’N 109°18’W) and the Yécora (YEC) area in the Sierra Madre Occidental (SMO) in eastern Sonora (28°25’N 109°15”W) were compared. The areas are 175 km apart. Tropical vegetation includes foothills thornscrub (FTS) in both areas and tropical deciduous...

  11. Recommendations from the Sierra Club for managing Giant Sequoia

    Joseph Fontaine

    1986-01-01

    The giant sequoia (Sequoiadendron giganteum [Lindl.] Buchholz) groves in their natural setting are one of the outstanding scenic features of the southern Sierra Nevada. These groves where they have survived should be man-aged to protect their natural values and to restore former natural conditions wherever possible. Groves that are essentially intact...

  12. Color and 3D views of the Sierra Nevada mountains

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A stereo 'anaglyph' created using the nadir and 45.6-degree forward-viewing cameras provides a three-dimensional view of the scene when viewed with red/blue glasses. The red filter should be placed over your left eye. To facilitate the stereo viewing, the images have been oriented with north toward the left. Some prominent features are Mono Lake, in the center of the image; Walker Lake, to its left; and Lake Tahoe, near the lower left. This view of the Sierra Nevadas includes Yosemite, Kings Canyon, and Sequoia National Parks. Mount Whitney, the highest peak in the contiguous 48 states (elev. 14,495 feet), is visible near the righthand edge. Above it (to the east), the Owens Valley shows up prominently between the Sierra Nevada and Inyo ranges. Precipitation falling as rain or snow on the Sierras feeds numerous rivers flowing southwestward into the San Joaquin Valley. The abundant fields of this productive agricultural area can be seen along the lower right; a large number of reservoirs that supply water for crop irrigation are apparent in the western foothills of the Sierras. Urban areas in the valley appear as gray patches; among the California cities that are visible are Fresno, Merced, and Modesto.

  13. Diets of California spotted owls in the Sierra National Forest

    Thomas E. Munton; Kenneth D. Johnson; George N. Steger; Gary P. Eberlein

    2002-01-01

    From May 1987 through October 1992 and from July through August 1998, we studied diets of California spotted owls (Strix occidentalis occidentalis). Regurgitated pellets were collected at roost and nest sites between 1,000 and 7,600 ft elevation in the Sierra National Forest and were examined for remnant bones, feathers, and insect exoskeletons....

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

    ERIC Educational Resources Information Center

    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…

  15. Verification Tests for Sierra/SM's Reproducing Kernal Particle Method

    SciT

    Giffin, Brian D.

    2015-09-01

    This report seeks to verify the proper implemention of RKPM within Sierra by comparing the results from several basic example problems excecuted with RKPM against the analytical and FEM solutions for these same problems. This report was compiled as a summer student intern project.

  16. 75 FR 76975 - 2015 Resource Pool-Sierra Nevada Region

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ...The Western Area Power Administration (Western), a Federal power marketing administration of DOE, announces the Final 2015 Resource Pool allocations pursuant to its 2004 Power Marketing Plan (Marketing Plan) for the Sierra Nevada Customer Service Region (SNR). This notice includes a summary of the comments received on Western's proposed 2015 Resource Pool allocations and Western's responses.

  17. The status and conservation of mesocarnivores in the Sierra Nevada

    William J. Zielinski

    2004-01-01

    Carnivores play important roles in structuring communities, and their populations are useful indicators of ecosystem condition (Wennergren and others 1995, Buskirk 1999, Crooks and Soulé 1999, Terborgh and others 2001). As many as 4 of 20 native mammalian carnivore species have been extirpated from the southern Cascade Mountains and Sierra Nevada, with unmeasured...

  18. Tone Gestures and Constraint Interaction in Sierra Juarez Zapotec

    ERIC Educational Resources Information Center

    Tejada, Laura

    2012-01-01

    This dissertation examines floating tones and tone gesture deactivation in Sierra Juarez Zapotec (SJZ), and provides an Optimality Theoretic account of tonal spreading and placement using insights from Articulatory Phonology. While the data portion of the dissertation is drawn from SJZ, the approach has broader implications for theories of tonal…

  19. Chapter 15: A desired future condition for Sierra Nevada Forests

    M. North

    2012-01-01

    An unexpected outcome of U.S. Forest Service General Technical Report PSW-GTR 220, "An Ecosystem Management Strategy for Sierran Mixed-Conifer Forests" (North et al. 2009), was how it generated discussion about a desired future condition for Sierra Nevada forests. The paper did not convey leading-edge research results or provide an exhaustive literature...

  20. Sierra Health Foundation's Positive Youth Justice Initiative. Briefing Paper

    ERIC Educational Resources Information Center

    Sierra Health Foundation, 2012

    2012-01-01

    In December 2011, the Sierra Health Foundation board of directors approved a framework for a new youth development initiative. The framework built upon the foundation's recently concluded REACH Youth Development Program and incorporated findings and recommendations from the highly regarded "Healthy Youth/Healthy Regions" and…

  1. Ecosystems and diversity of the Sierra Madre Occidental

    M. S. Gonzalez-Elizondo; M. Gonzalez-Elizondo; L. Ruacho Gonzalez; I. L. Lopez Enriquez; F. I . Retana Renteria; J. A. Tena Flores

    2013-01-01

    The Sierra Madre Occidental (SMO) is the largest continuous ignimbrite plate on Earth. Despite its high biological and cultural diversity and enormous environmental and economical importance, it is yet not well known. We describe the vegetation and present a preliminary regionalization based on physiographic, climatic, and floristic criteria. A confluence of three main...

  2. 76 FR 53663 - Sierra County Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-29

    ... provide advice and recommendations to the Forest Service concerning projects and funding consistent with... and vote on projects submitted for funding and the expenditure of Title II funds benefiting National Forest System lands in Sierra County. DATES: The meeting will be held Monday, September 12, 2011 at 9 a.m...

  3. Meadows in the Sierra Nevada of California: state of knowledge

    Raymond D. Ratliff

    1985-01-01

    This state-of-knowledge report summarizes the best available information on maintenance, restoration, and management of meadows of the Sierra Nevada, California. Major topics discussed include how to classify meadows, meadow soils, productivity of meadows, management problems, and how to evaluate range conditions and trends. Current methods and standards are reviewed,...

  4. Friends of the Inyo: Eastern Sierra Wilderness Stewardship Project

    Paul McFarland; Jamie Anderson

    2007-01-01

    Friends of the Inyo is a non-profit, conservation organization dedicated to preserving public lands and wildlife of the Eastern Sierra. First founded in 1986, Friends of the Inyo hired its first staff person in 2000. Today, the organization enjoys a vibrant and growing membership of 500 individuals and employs three people-Executive Director, Paul McFarland (the...

  5. Nest trees of northern flying squirrels in the Sierra Nevada

    Marc D. Meyer; Douglas A. Kelt; Malcolm P. North

    2005-01-01

    We examined the nest-tree preferences of northern flying squirrels (Glaucomys sabrinus) in an old-growth, mixed-conifer and red fir (Abies magnifica) forest of the southern Sierra Nevada of California. We tracked 27 individuals to 122 nest trees during 3 summers. Flying squirrels selected nest trees that were larger in diameter and...

  6. Precipitation Structure in the Sierra Nevada of California During Winter

    NASA Technical Reports Server (NTRS)

    Pandey, Ganesh R.; Cayan, Daniel R.; Georgakakos, Kostantine P.

    1998-01-01

    The influences of upper air characteristics along the coast of California upon the winter time precipitation in the Sierra Nevada region were investigated. Most precipitation episodes in the Sierra are associated with moist southwesterly winds and also tend to occur when the 700-mb temperature is close to -2 C. This favored wind direction and temperature signifies the equal importance of moisture transport and orographic lifting for maximum precipitation frequency. Making use of this observation, simple linear models were formulated to quantify the precipitation totals observed at different sites as a function of moisture transport. The skill of the model is least for daily precipitation and increases with time scale of aggregation. In terms of incremental gain, the skill of the model is optimal for an aggregation period of 5-7 days, which is also the duration of the most frequent precipitation events in the Sierra. This indicates that upper air moisture transport at can be used to make reasonable estimates of the precipitation totals for most frequent events in the Sierra region.

  7. Riparian Communities of the Sierra Nevada and their Environmental Relationships

    Richard R. Harris

    1989-01-01

    Data on riparian community composition and environmental conditions were collected on over 20 streams in the Sierra Nevada as part of hydropower licensing studies. Over 1,000 samples were analyzed using two-way indicator species analysis (TWINSPAN), to determine riparian dominance types. Ordination techniques were applied to evaluate associations between environmental...

  8. SURVEY OF LIBRARY PERSONNEL IN SIERRA COLLEGE EMPLOYMENT AREA.

    ERIC Educational Resources Information Center

    YOUNG, ELMA L.

    FOR TWO YEARS PRIOR TO THIS STUDY, SIERRA COLLEGE, CALIFORNIA, HAD OFFERED LIBRARY TECHNICIAN TRAINING IN ITS EVENING PROGRAM. A SURVEY OF LIBRARIES IN THE 5-COUNTY EMPLOYMENT AREA OF THE COLLEGE'S GRADUATES WAS MADE IN 1968 TO DETERMINE NEEDS FOR LIBRARY TECHNICIANS. IN THE FIVE COUNTIES, 167 LIBRARIES WERE IDENTIFIED, WITH A TOTAL OF 1084…

  9. Military Interventions in Sierra Leone: Lessons from a Failed State

    DTIC Science & Technology

    2008-01-01

    enslaved from Sierra Leone were shipped to the Caribbean and Brazil . This heinous trade lasted for over 100 years. Competing religious...Bana. Map 6. Operation BARRAS area of operations. 67 Magbeni and Gberi Bana were surrounded by dense jungle vegeta­ tion, mangrove swamps, murky

  10. Watershed Restoration in the Northern Sierra Nevada: A Biotechnical Approach

    Donna S. Lindquist; Linton Y. Bowie

    1989-01-01

    A cooperative erosion control project was initiated in 1985 for the North Fork Feather River watershed in California's northern Sierra Nevada due to widespread accelerated erosion. Resulting sedimentation problems have impacted fish, wildlife and livestock resources, and have created operational concerns for hydroelectric facilities located downstream. In response...

  11. Correlation of the Klamath Mountains and Sierra Nevada

    Irwin, William P.

    2003-01-01

    This report graphically portrays the broadly parallel tectonic development of the Klamath Mountains and Sierra Nevada from early Paleozoic to Early Cretaceous time. It is dedicated to J.S. Diller of the U.S. Geological Survey who, during his pioneer field studies a century ago, recognized significant similarities between these two important provinces. The report is based mainly on the numerous published reports of the field and laboratory studies by various geologists and students during the last century, and to a lesser extent on my own field work which has been substantial in the Klamath Mountains but minimal in the Sierra Nevada. For brevity, required by the format of this report, little of the extensive literature pertaining to these two provinces is referenced. This report is preliminary in nature and was prepared as an aid to further study of the tectonic relations between the Klamath Mountains and Sierra Nevada. This report consists of two sheets: Sheet 1, Map showing accreted terranes and plutons of the Klamath Mountains and Sierra Nevada, and Sheet 2, Successive accretionary episodes of the Klamath mountains and northern part of Sierra Nevada, showing related plutonic, volcanic, and metamorphic events. The map on Sheet 1 was compiled and modified from two Open-File maps (Irwin and Wooden, 1999 and 2001) which had been compiled and modified mainly from Jennings (1977), Harwood (1992), Irwin (1994), Jayko (1988), Graymer and Jones (1994), Edelman and Sharp (1989), Schweickert and others (1999), Saucedo and Wagner(1992), Saleeby and Sharp (1980), Wagner and others (1981), and various other sources. For detailed lists of the sources for the isotopic age data used in Sheets 1 and 2, see Irwin and Wooden (1999 and 2001). On Sheet 2, the accretionary episodes are shown sequentially from left to right in two tiers of figures. Episodes for the Klamath Mountains are in the upper tier; correlative episodes of the Sierra Nevada are directly below in the lower tier

  12. Lassa fever in post-conflict sierra leone.

    PubMed

    Shaffer, Jeffrey G; Grant, Donald S; Schieffelin, John S; Boisen, Matt L; Goba, Augustine; 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

    2014-03-01

    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 LF.

  13. Lassa Fever in Post-Conflict Sierra Leone

    PubMed Central

    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

  14. Rangewide glaciation in the Sierra Nevada, California

    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

  15. Sierra Nevada Science Review. Report of the Science Review Team charged to synthesize new information of rangewide urgency to the national forests of the Sierra Nevada.

    Constance Millar; Amy Lind; Rowan Rowntree; Carl Skinner; Jared Verner; William J. Zielinski; Robert R. Ziemer

    1998-01-01

    In January, 1998, the Pacific Southwest Region and Pacific Southwest Research Station of the Forest Service initiated a collaborative effort to incorporate new information into planning future management of Sierra Nevada national forests. The project, known as the Sierra Nevada Framework for Conservation and Collaboration, will incorporate the latest scientific...

  16. Predictions of fire behavior and resistance to control: for use with photo series for the sierra mixed conifer type and the sierra true fir type.

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance: of fuels to control. The information is to be used with the photos in the publication, "Photo Series for Quantifying Forest Residues in the Sierra Mixed Conifer Type, Sierra True Fir Type" (Maxwell, Wayne G.; Ward, Franklin R. 1979. Gen. Tech. Rep. PNW-GTR-095. Portland, OR: U.S....

  17. Level-2 Milestone 6007: Sierra Early Delivery System Deployed to Secret Restricted Network

    SciT

    Bertsch, A. D.

    This report documents the delivery and installation of Shark, a CORAL Sierra early delivery system deployed on the LLNL SRD network. Early ASC program users have run codes on the machine in support of application porting for the final Sierra system which will be deployed at LLNL in CY2018. In addition to the SRD resource, Shark, unclassified resources, Rzmanta and Ray, have been deployed on the LLNL Restricted Zone and Collaboration Zone networks in support of application readiness for the Sierra platform.

  18. SIERRA/Aero Theory Manual Version 4.46.

    SciT

    Sierra Thermal/Fluid Team

    2017-09-01

    SIERRA/Aero is a two and three dimensional, node-centered, edge-based finite volume code that approximates the compressible Navier-Stokes equations on unstructured meshes. It is applicable to inviscid and high Reynolds number laminar and turbulent flows. Currently, two classes of turbulence models are provided: Reynolds Averaged Navier-Stokes (RANS) and hybrid methods such as Detached Eddy Simulation (DES). Large Eddy Simulation (LES) models are currently under development. The gas may be modeled either as ideal, or as a non-equilibrium, chemically reacting mixture of ideal gases. This document describes the mathematical models contained in the code, as well as certain implementation details. First, themore » governing equations are presented, followed by a description of the spatial discretization. Next, the time discretization is described, and finally the boundary conditions. Throughout the document, SIERRA/ Aero is referred to simply as Aero for brevity.« less

  19. SIERRA/Aero Theory Manual Version 4.44

    SciT

    Sierra Thermal /Fluid Team

    2017-04-01

    SIERRA/Aero is a two and three dimensional, node-centered, edge-based finite volume code that approximates the compressible Navier-Stokes equations on unstructured meshes. It is applicable to inviscid and high Reynolds number laminar and turbulent flows. Currently, two classes of turbulence models are provided: Reynolds Averaged Navier-Stokes (RANS) and hybrid methods such as Detached Eddy Simulation (DES). Large Eddy Simulation (LES) models are currently under development. The gas may be modeled either as ideal, or as a non-equilibrium, chemically reacting mixture of ideal gases. This document describes the mathematical models contained in the code, as well as certain implementation details. First, themore » governing equations are presented, followed by a description of the spatial discretization. Next, the time discretization is described, and finally the boundary conditions. Throughout the document, SIERRA/ Aero is referred to simply as Aero for brevity.« less

  20. Application Modernization at LLNL and the Sierra Center of Excellence

    SciT

    Neely, J. Robert; de Supinski, Bronis R.

    We repport that in 2014, Lawrence Livermore National Laboratory began acquisition of Sierra, a pre-exascale system from IBM and Nvidia. It marks a significant shift in direction for LLNL by introducing the concept of heterogeneous computing via GPUs. LLNL’s mission requires application teams to prepare for this paradigm shift. Thus, the Sierra procurement required a proposed Center of Excellence that would align the expertise of the chosen vendors with laboratory personnel that represent the application developers, system software, and tool providers in a concentrated effort to prepare the laboratory’s codes in advance of the system transitioning to production in 2018.more » Finally, this article presents LLNL’s overall application strategy, with a focus on how LLNL is collaborating with IBM and Nvidia to ensure a successful transition of its mission-oriented applications into the exascale era.« less

  1. Failure of Sierra White granite under general states of stress

    NASA Astrophysics Data System (ADS)

    Ingraham, M. D.; Dewers, T. A.; Lee, M.; Holdman, O.; Cheung, C.; Haimson, B. C.

    2017-12-01

    The effect of the intermediate principal stress on the failure of Sierra White granite was investigated by performing tests under true triaxial states of stress. Tests were performed under constant Lode angle conditions with Lode angles ranging from 0 to 30°, pure shear to axisymmetric compression. Results show that the failure of Sierra White granite is heavily dependent on the intermediate principal stress which became more dramatic as the mean stress increased. An analysis of the shear bands formed at failure was performed using an associated flow rule and the Rudnicki and Rice (1975) localization criteria. The localization analysis showed excellent agreement with experimental results. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  2. Application Modernization at LLNL and the Sierra Center of Excellence

    DOE PAGES

    Neely, J. Robert; de Supinski, Bronis R.

    2017-09-01

    We repport that in 2014, Lawrence Livermore National Laboratory began acquisition of Sierra, a pre-exascale system from IBM and Nvidia. It marks a significant shift in direction for LLNL by introducing the concept of heterogeneous computing via GPUs. LLNL’s mission requires application teams to prepare for this paradigm shift. Thus, the Sierra procurement required a proposed Center of Excellence that would align the expertise of the chosen vendors with laboratory personnel that represent the application developers, system software, and tool providers in a concentrated effort to prepare the laboratory’s codes in advance of the system transitioning to production in 2018.more » Finally, this article presents LLNL’s overall application strategy, with a focus on how LLNL is collaborating with IBM and Nvidia to ensure a successful transition of its mission-oriented applications into the exascale era.« less

  3. Sequence Variability and Geographic Distribution of Lassa Virus, Sierra Leone

    PubMed Central

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

    2015-01-01

    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. PMID:25811712

  4. Groundwater quality in the Central Sierra Nevada, California

    Fram, Miranda S.; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. Two small watersheds of the Fresno and San Joaquin Rivers in the Central Sierra Nevada constitute one of the study units being evaluated.

  5. Groundwater quality in the Southern Sierra Nevada, California

    Fram, Miranda S.; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Tehachapi-Cummings Valley and Kern River Valley basins and surrounding watersheds in the Southern Sierra Nevada constitute one of the study units being evaluated.

  6. Courtright intrusive zone: Sierra National Forest, Fresno County, California.

    Bateman, P.C.; Kistler, R.W.; DeGraff, J.V.

    1984-01-01

    This is a field guide to a well-exposed area of plutonic and metamorphic rocks in the Sierra National Forest, Fresno County, California. The plutonic rocks, of which three major bodies are recognized, besides aplite and pegmatite dykes, range 103 to approx 90 m.y. in age. Points emphasized include cataclastic features within the plutonic rocks, schlieren and mafic inclusions. (M.A. 83M/0035).-A.P.

  7. Health complications of female genital mutilation in Sierra Leone

    PubMed Central

    Bjälkander, Owolabi; Bangura, Laurel; Leigh, Bailah; Berggren, Vanja; Bergström, Staffan; Almroth, Lars

    2012-01-01

    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 undergo FGM before 10 years of age seem to be more vulnerable to serious complications than those who are older at the time of FGM. It is important that health care personnel are aware of, and look for possible complications from FGM, and encourage girls and women to seek medical care for their problems. PMID:22870046

  8. Precipitation structure in the Sierra Nevada of California during winter

    Pandey, G.R.; Cayan, D.R.; Georgakakos, K.P.

    1999-01-01

    Influences of upper air characteristics along the coast of California upon wintertime (November-April) precipitation in the Sierra Nevada are investigated. Precipitation events in the Sierra Nevada region occur mostly during wintertime, irrespective of station location (leeside or wihdside) and elevation. Most precipitation episodes in the region are associated with moist southwesterly winds (coming from the southwest direction) and also tend to occur when the 700-mbar temperature at the upwind direction is close to -2??C. This favored wind direction and temperature signify the importance of both moisture transport and orographic lifting in augmenting precipitation in the region. By utilizing the observed dependency of the precipitation upon the upper air conditions, a linear model is formulated to quantify the precipitation observed at different sites as a function of moisture transport. The skill of the model increases with timescale of aggregation, reaching more than 50% variance explained at an aggregation period of 5-7 days. This indicates that upstream air moisture transport can be used to estimate the precipitation totals in the Sierra Nevada region. Copyright 1999 by the American Geophysical Union.

  9. Individual and community perceptions of surgical care in Sierra Leone.

    PubMed

    Groen, Reinou S; Sriram, Veena M; Kamara, Thaim B; Kushner, Adam L; Blok, Lucie

    2014-01-01

    To determine themes and beliefs that influence health-seeking behaviour and barriers to accessing surgical care. In January 2012 in Western Area Province of Sierra Leone, six Focus Group Discussions (FGDs) were conducted. The FDGs consisted of three male only and three female only groups in an urban, a slum and a rural setting. Researchers investigated a wide range of topics including definitions of surgery, types of surgical procedures, trust, quality of care, human resources, post-operative care, permission-seeking and traditional beliefs. Although many individual beliefs were expressed, common fears were as follows: becoming half human after surgery; complications from procedures; stigma from having a scar; and financial burdens resulting from the cost of care. Participants also expressed concern about the quality of the care available in Sierra Leone. The concept of being half human after surgery, previously not documented in the literature, is noteworthy and should be explored more fully. Qualitative research in other parts of Sierra Leone and other LMICs into beliefs of the local population could improve programmes for access and delivery of surgical care. © 2013 John Wiley & Sons Ltd.

  10. The burden of musculoskeletal disease in Sierra Leone.

    PubMed

    Elliott, Iain S; Groen, Reinou S; Kamara, Thaim B; Ertl, Allison; Cassidy, Laura D; Kushner, Adam L; Gosselin, Richard A

    2015-01-01

    Musculoskeletal disease is a major cause of disability in the global burden of disease, yet data regarding the magnitude of this burden in developing countries are lacking. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) survey was designed to measure the incidence and prevalence of surgically treatable conditions, including musculoskeletal conditions, in patients in low- and middle-income countries, and was administered in the West African nation of Sierra Leone in 2012. We attempted to quantify the burden of potentially treatable musculoskeletal conditions in patients in Sierra Leone. A cross-sectional two-stage cluster-based survey was performed in Sierra Leone using the SOSAS. Two individuals from each randomly selected household underwent a verbal head to toe examination. The musculoskeletal-related questions from the SOSAS survey in Sierra Leone were analyzed to determine the prevalence of musculoskeletal problems in the study population. Prevalence is reported as the number of respondents with a musculoskeletal problem now and number of respondents with a musculoskeletal problem during the past year. Respondents had "no need" for care, they "received care", or they faced a barrier that prevented them from receiving care. One thousand eight hundred seventy-five households were targeted, with 1843 undergoing the survey, which yielded 3645 individual respondents. Of the individual respondents, 462 (n=3645; 12.6% of total; 95% CI, 12%-13%) had a traumatic musculoskeletal problem during the past year, and 236 (n=3645; 6% of total; 95% CI, 5%-7%) respondents had a musculoskeletal problem of nontraumatic etiology. Of respondents with either a traumatic or nontraumatic musculoskeletal problem, 359 (n=562; 63.9% of total; 95% CI, 59.5-68.3%) needed care but were unable to receive it with the major barrier reported as financial. Resource allocation decisions in global health are made based on burden of disease data in low- and middle-income countries. The

  11. California Drought Effects on Sierra Trees Mapped by NASA

    2016-06-27

    California, reveals the devastating effect of California's ongoing drought on Sierra Nevada conifer forests. The map will be used to help the U.S. Forest Service assess and respond to the impacts of increased tree mortality caused by the drought, particularly where wildlands meet urban areas within the Sierra National Forest. After several years of extreme drought, the highly stressed conifers (trees or bushes that produce cones and are usually green year-round) of the Sierra Nevada are now more susceptible to bark beetles (Dendroctonus spp.). While bark beetles killing trees in the Sierra Nevada is a natural phenomenon, the scale of mortality in the last couple of years is far greater than previously observed. The U.S. Forest Service is using recent airborne spectroscopic measurements from NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) instrument aboard NASA's ER-2 aircraft, together with new advanced algorithms, to quantify this impact over this large region of rugged terrain. The high-altitude ER-2 aircraft is based at NASA's Armstrong Flight Research Center, Edwards, California. The image was created by scientists at the USFS's Pacific Southwest Region Remote Sensing Lab, McClellan, California, by performing a time series analysis of AVIRIS images. Scientists evaluated baseline tree mortality on public lands in the summer of 2015 using a machine learning algorithm called "random forest." This algorithm classifies the AVIRIS measurements as dominated by either shrubs, healthy trees or newly dead conifer trees. To quantify how much the amount of dead vegetation increased during the fall of 2015, the Forest Service scientists conducted an advanced spectral mixture analysis. This analysis evaluates each spectrum to determine the fraction of green vegetation, dead vegetation and soil. The full spectral range of AVIRIS is important to separate the signatures of soil and dead vegetation. To produce this comprehensive Sierra National Forest tree

  12. Updated paleomagnetic pole from Cretaceous plutonic rocks of the Sierra Nevada, California: Tectonic displacement of the Sierra Nevada block

    Hillhouse, John W.; Gromme, Sherman

    2011-01-01

    We report remanent magnetization measurements from 13 sites in Cretaceous plutonic rocks in the northern Sierra Nevada (38°N–39.5°N). By increasing the number of available paleomagnetic sites, the new data tighten constraints on the displacement history of the Sierra Nevada block and its pre-extensional position relative to interior North America. We collected samples in freshly exposed outcrops along four highway transects. The rocks include diorite, granodiorite, and tonalite with potassium-argon ages (hornblende) ranging from 100 Ma to 83 Ma. By combining our results with previous paleomagnetic determinations from the central and southern Sierra Nevada (excluding sites from the rotated southern tip east of the White Wolf–Kern Canyon fault system), we find a mean paleomagnetic pole of 70.5°N, 188.2°E, A95 = 2.6° (N = 26, Fisher concentration parameter, K = 118). Thermal demagnetization indicates that the characteristic remanence is generally unblocked in a narrow range within 35 °C of the Curie temperature of pure magnetite. Small apparent polar wander during the Cretaceous normal-polarity superchron, plus prolonged acquisition of remanence at the site level, may account for the low dispersion of virtual geomagnetic poles and relatively large K value. Tilt estimates based on overlapping sediments, stream gradients, and thermochronology of the Sierra Nevada plutons vary from 0° to 3° down to the southwest. Without tilt correction, the mean paleomagnetic pole for the Sierra Nevada is essentially coincident with the North American reference pole during the Cretaceous stillstand (125 Ma to 80 Ma). At 95% confidence, the apparent latitude shift is 1.1° ± 3.0° (positive northward), and the apparent rotation is negligible, 0.0° ± 4.7°. Correcting for each degree of tilt, which is limited to 3° on geologic evidence, increases the rotation anomaly 2.2° counterclockwise, while the apparent latitude shift remains unchanged.

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

    DTIC Science & Technology

    2010-03-01

    6 A. M. Fitz -Gerald, Security Sector Reform in Sierra Leone. Shrivenham, GFN-SSR. 8–10. Osman Gbla...34Security Sector Reform: Bringing the Private in.", 1– 23; Peter Albrecht and Paul Jackson, eds. Security System Transformation in Sierra Leone, 1997–2007...veterans.38 33 John R. Cartwright, Political leadership in Sierra Leone (Toronto: University of

  14. Shorthair meadows in the high Sierra Nevada...an hypothesis of their development

    Raymond D. Ratliff

    1973-01-01

    Bands of shorthair meadow are found around lakes in the high Sierra Nevada of California. A hypothesis, based on observations in the Kings Canyon National Park, to explain the development of these meadows is offered: Boulders form the foundation upon which American-laurel, Sierra bilberry, and moss combine to produce thick mats. The lower layers of the mats are...

  15. Curriculum Diversification Re-examined--A Case Study of Sierra Leone.

    ERIC Educational Resources Information Center

    Wright, Cream A. H.

    This paper deals with a case study of secondary curriculum diversification as a vocationalization strategy in Sierra Leone. It explores diversification issues from four crucial standpoints that are distinct but highly interrelated. First, diversification is dealt with as a policy that was adopted and actively pursued by Sierra Leone for over a…

  16. Attracting, Recruiting, and Retaining Qualified Faculty at Community Colleges in Sierra Leone

    ERIC Educational Resources Information Center

    Betts, Gloria

    2017-01-01

    This case study was designed to explore policies that were in place to attract, recruit, and retain qualified faculty for 4 community colleges in Sierra Leone. The research was necessitated by the apparent inability of Sierra Leone educators to train and retain faculty possessing the required academic credentials. The research questions were…

  17. Sampling affects the detection of genetic subdivision and conservation implications for fisher in the Sierra Nevada

    Jody M. Tucker; Michael K. Schwartz; Richard L. Truex; Samantha M. Wisely; Fred W. Allendorf

    2014-01-01

    The small population of fisher (Pekania pennanti) in the southern Sierra Nevada is completely geographically and genetically isolated putting it at increased risk of extinction. Previous research using a clustered sampling scheme found a high amount of genetic subdivision within the southern Sierra Nevada population hypothesized to be caused by the Kings River Canyon....

  18. Response of two terrestrial salamander species to spring burning in the Sierra Nevada, California

    Karen E. Bagne; Kathryn L. Purcell

    2009-01-01

    Terrestrial salamanders may be vulnerable to prescribed fire applications due to their moist, permeable skin and limited mobility. We present data collected on terrestrial salamander populations in a ponderosa pine-dominated forest in the Sierra Nevada where fire was applied in the spring. Two species, Sierra ensatina (Ensatina eschscholtzi platensis...

  19. 77 FR 23130 - Revisions to the California State Implementation Plan, Northern Sierra and Sacramento...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ... taking direct final action to approve revisions to the Northern Sierra Air Quality Management District (NSAQMD) and Sacramento Metropolitan Air Quality Management District (SMAQMD) portions of the California...) Northern Sierra Air Quality Management District. (i) Flexible Package Printing, Flat Wood Paneling Coatings...

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

    ERIC Educational Resources Information Center

    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…

  1. High Sierra Ecosystems: The Role of Fish Stocking in Amphibian Declines

    Kathleen Matthews

    2003-01-01

    With a rich diversity of aquatic habitats, including deep lakes, shallow ponds, and rushing streams, Dusy Basinin Sequoia-Kings Canyon National Parks typifies the high Sierra ecosystem where mountain yellow-legged frogs usually thrive. Yet throughout the Sierra, aquatic ecologist Kathleen Matthews found entire water basins empty of these amphibians. Comprehensive...

  2. High Sierra ecosystems: the role of fish stocking in amphibian declines

    Anne M. Rosenthal; Kathleen R. Featured: Matthews

    2003-01-01

    With a rich diversity of aquatic habitats, including deep lakes, shallow ponds, and rushing streams, Dusy Basin in Sequoia-Kings Canyon National Parks typifies the high Sierra ecosystem where mountain yellow-legged frogs usually thrive. Yet throughout the Sierra, aquatic ecologist Kathleen Matthews found entire water basins empty of these amphibians. Comprehensive...

  3. Prediction of periodic basal area increment for young-growth mixed conifers in sierra Nevada

    Leroy K. Dolph

    1988-01-01

    Mixed-conifer forests are the largest vegetation type in California, covering more than 13 million acres (Barbour and Major 1977). This type, the Sierra Nevada Mixed Conifer (Society of American Foresters Forest cover type 243, Tappeiner 1980) dominates mid-elevations of the Sierra Nevada's western slopes. The extent of the mixed-conifer type and the amount of...

  4. 78 FR 2391 - Sierra Pacific Power Company; Notice of Initiation of Proceeding and Refund Effective Date

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-11

    ... Power Company; Notice of Initiation of Proceeding and Refund Effective Date On December 31, 2012, the... reasonableness of the proposed transmission and ancillary service rates by Sierra Pacific Power Company. Sierra Pacific Power Company, 141 FERC ] 61,266 (2012). The refund effective date in Docket No. EL13-29-000...

  5. Summer evapotranspiration trends as related to time after logging of forests in Sierra Nevada

    Robert R. Ziemer

    1964-01-01

    Abstract - The quantity of summer soil moisture lost from logged forest openings was related to the length of time since the creation of the opening, in the subalpine forest zone of the Sierra Nevada west side, near the Central Sierra Snow Laboratory, California, at an elevation of 6000 to 7000 feet. Soil moisture depletion was measured in forest openings which were...

  6. A preliminary floristic inventory in the Sierra de Mazatan, Municipios of Ures and Mazatan, Sonora, Mexico

    Jose Jesus Sanchez-Escalante; Manuel Espericueta-Betancourt; Reyna Amanda Castillo-Gamez

    2005-01-01

    Presently, the flora of the Sierra de Mazatán contains 357 species of vascular plants distributed in 248 genera and 80 families. The families with the most species are Asteraceae (48), Fabaceae (45), Poaceae (28), Euphorbiaceae (18), and Acanthaceae, Cactaceae, Scrophulariaceae, and Solanaceae (11 each). The results show that the flora of the Sierra de Mazat...

  7. Building effective international, multicultural alliances for restoration of ejido forests in the Sierra Madre Occidental

    Randall Gingrich

    2005-01-01

    Effective NGO-government-community alliances are the key to overcoming the complex socio-political obstacles to conservation in the Sierra Madre Occidental. Over 80 percent of the territory in the Sierra Madre Occidental is communally owned. Agrarian and other socio-economic conditions present both opportunities and obstacles to conservation. Conservation,...

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

    ERIC Educational Resources Information Center

    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.…

  9. Nitrogen dynamics of spring-fed wetland ecosystems of the Sierra Nevada foothills oak woodland

    Randall D. Jackson; Barbara Allen-Diaz

    2002-01-01

    Spring-fed wetlands are small, highly productive, patchy ecosystems nested within the oak woodland/annual grassland matrix of the Sierra Nevada foothills. In an effort to place these wetlands in a landscape context, we described seasonal variation (1999-2000 growing season) in nitrogen cycling parameters at 6 spring-fed wetland sites of the Sierra Nevada foothill oak...

  10. Increasing elevation of fire in the Sierra Nevada and implications for forest change

    Mark W. Schwartz; Nathalie Butt; Christopher R. Dolanc; Andrew Holguin; Max A. Moritz; Malcolm P. North; Hugh D. Safford; Nathan L. Stephenson; James H. Thorne; Phillip J. van Mantgem

    2015-01-01

    Fire in high-elevation forest ecosystems can have severe impacts on forest structure, function and biodiversity. Using a 105-year data set, we found increasing elevation extent of fires in the Sierra Nevada, and pose five hypotheses to explain this pattern. Beyond the recognized pattern of increasing fire frequency in the Sierra Nevada since the late 20th century, we...

  11. Sierra/SolidMechanics 4.48 User's Guide: Addendum for Shock Capabilities.

    SciT

    Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

    This is an addendum to the Sierra/SolidMechanics 4.48 User's Guide that documents additional capabilities available only in alternate versions of the Sierra/SolidMechanics (Sierra/SM) code. These alternate versions are enhanced to provide capabilities that are regulated under the U.S. Department of State's International Traffic in Arms Regulations (ITAR) export-control rules. The ITAR regulated codes are only distributed to entities that comply with the ITAR export-control requirements. The ITAR enhancements to Sierra/SM in- clude material models with an energy-dependent pressure response (appropriate for very large deformations and strain rates) and capabilities for blast modeling. Since this is an addendum to the standardmore » Sierra/SM user's guide, please refer to that document first for general descriptions of code capability and use.« less

  12. Modeling Patterns of Precipitation Phase in the Central Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Strikas, O.; Pavelsky, T.

    2013-12-01

    Snowpack provides 75% of summer hydrologic flow in the western United States. This summer flow is vitally important in California, the country's leading producer of agriculture, with $43.5 billion dollars in cash receipts in 2011. Snowpack in the California Sierra Nevada has declined by approximately half from 1900 to 1990. In this study, we use the Weather Research and Forecasting (WRF) regional climate model at a 3km resolution to understand the critical temperature window at which both snow and rain fall for the Central Sierra Nevada during the 2002 water year. Results suggest that temperature and snow fraction [snowfall / (snowfall + rainfall)] share a logistic relationship with the snow fraction being 1 until approximately 272 K, then the snow fraction decreases by approximately 22%/K leveling at 0 snow fraction at 276.5 K. We further examine the spatial patterns of temperatures, precipitation amounts, and precipitation types in the Sierra Nevada to determine the areas of greatest potential snow to rain transition under a future warmer climate. Preliminary results suggest that the high risk areas are at the low to mid elevations. This research provides evidence that even a minor increase in temperature (+0.5 K) will yield changes in spring and summer hydrographs for the region. The spatial variability of IPCC temperature regime change for 2050 and 2100 will be downscaled for a higher resolution prediction of precipitation. It is currently under investigation how the proposed IPCC (A1 and B2) predictions of climate change for the region by 2050 (+2.7 K; +1.6 K ) and 2100 (+4.4 K; +2.7 K) will alter the corresponding annual river hydrographs. Given the complex topography of the Sierra Nevada, several spatial interpolations using GIS and statistical algorithms will be executed to render this high resolution (3km) output. Other future work with collaborators intends to model the agricultural risk associated with our predicted changes. This plot demonstrates the

  13. Mountain Meadows and their contribution to Sierra Nevada Water Resources

    NASA Astrophysics Data System (ADS)

    Cornwell, K.; Brown, K.; Monohan, C.

    2007-12-01

    Human alterations of California's waterscape have exploited rivers, wetlands and meadows of the Sierra Nevada. A century of intensive logging, mining, railroad building, development, fire suppression, and grazing by sheep and cattle has left only 25 percent "intact" natural habitat in the Sierra Nevada (SNEP 1995). Much of this intact habitat occurs at higher elevations, often in non-forested alpine or in less productive forests and woodlands where mountain meadows exist. Mountain meadows serve many ecological functions including habitat for threatened and endangered terrestrial and aquatic species, and are considered to be essential physical components to watershed function and hydrology with significant water storage, filtration and flood attenuation properties. This study evaluates the physical characteristics and hydrologic function of Clarks Meadow located in northern Sierra Nevada, Plumas County, California. In 2001, Clarks Meadow received significant restoration work in the upstream half of the meadow which diverted the stream from an incised channel to a shallow remnant channel, creating a stable channel and reconnecting the groundwater table to the stream. No restoration work was done in the lower half of Clarks Meadow where the stream still flows through an incised channel. Clarks Meadow offers a unique opportunity to study both a restored, hydrologically functional meadow and an incised, hydrologically disconnected stretch of the same stream and meadow. The physical characteristics of Clarks Meadows that were measured include surface area, subsurface thickness, porosity and permeability of subsurface materials, potential water storage volume, and surface infiltration rates. The goal of this study is to refine hydrologic characterization methods, quantify water storage potential of a healthy, non-incised meadow and assess its role in attenuating flood flows during high discharge times. Initial results suggest that significant subsurface storage volume is

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

    PubMed

    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." excerpt

  15. Environmental exposures to agrochemicals in the Sierra Nevada mountain range

    LeNoir, J.; Aston, L.; Data, S.; Fellers, G.; McConnell, L.; Sieber, J.

    2000-01-01

    The release of pesticides into the environment may impact human and environmental health. Despite the need for environmental exposure data, few studies quantify exposures in urban areas and even fewer determine exposures to wildlife in remote areas. Although it is expected that concentrations in remote regions will be low, recent studies suggest that even low concentrations may have deleterious effects on wildlife. Many pesticides are known to interfere with the endocrine systems of humans and wildlife, adversely affecting growth, development, and behavior. This chapter reviews the fate and transport of pesticides applied in the Central Valley of California and quantifies their subsequent deposition into the relatively pristine Sierra Nevada Mountain Range.

  16. Sierra Nevada, California as seen from STS-59

    1994-04-14

    STS059-L09-162 (9-20 April 1994) --- Orient with the snow-covered mountains (Sierra Nevada of California) in the upper right corner. Then Owens Valley runs along the top of the photograph to Owens Lake playa at top center. The upper end of Death Valley extends from right to left in the foreground, with the drainage running down to a playa at Stovepipe Wells in the left foreground. Geologists are studying microwave signatures of the different playa surfaces, and the coatings on alluvial fans that extend from mountain masses, to try to sort out the history of different climates in this formerly wet but now hyperarid region.

  17. Water quality associated public health risk in Bo, Sierra Leone.

    PubMed

    Jimmy, David H; Sundufu, Abu J; Malanoski, Anthony P; Jacobsen, Kathryn H; Ansumana, Rashid; Leski, Tomasz A; Bangura, Umaru; Bockarie, Alfred S; Tejan, Edries; Lin, Baochuan; Stenger, David A

    2013-01-01

    Human health depends on reliable access to safe drinking water, but in many developing countries only a limited number of wells and boreholes are available. Many of these water resources are contaminated with biological or chemical pollutants. The goal of this study was to examine water access and quality in urban Bo, Sierra Leone. A health census and community mapping project in one neighborhood in Bo identified the 36 water sources used by the community. A water sample was taken from each water source and tested for a variety of microbiological and physicochemical substances. Only 38.9% of the water sources met World Health Organization (WHO) microbial safety requirements based on fecal coliform levels. Physiochemical analysis indicated that the majority (91.7%) of the water sources met the requirements set by the WHO. In combination, 25% of these water resources met safe drinking water criteria. No variables associated with wells were statistically significant predictors of contamination. This study indicated that fecal contamination is the greatest health risk associated with drinking water. There is a need to raise hygiene awareness and implement inexpensive methods to reduce fecal contamination and improve drinking water safety in Bo, Sierra Leone.

  18. A Method for Snow Reanalysis: The Sierra Nevada (USA) Example

    NASA Technical Reports Server (NTRS)

    Girotto, Manuela; Margulis, Steven; Cortes, Gonzalo; Durand, Michael

    2017-01-01

    This work presents a state-of-the art methodology for constructing snow water equivalent (SWE) reanalysis. The method is comprised of two main components: (1) a coupled land surface model and snow depletion curve model, which is used to generate an ensemble of predictions of SWE and snow cover area for a given set of (uncertain) inputs, and (2) a reanalysis step, which updates estimation variables to be consistent with the satellite observed depletion of the fractional snow cover time series. This method was applied over the Sierra Nevada (USA) based on the assimilation of remotely sensed fractional snow covered area data from the Landsat 5-8 record (1985-2016). The verified dataset (based on a comparison with over 9000 station years of in situ data) exhibited mean and root-mean-square errors less than 3 and 13 cm, respectively, and correlation greater than 0.95 compared with in situ SWE observations. The method (fully Bayesian), resolution (daily, 90-meter), temporal extent (31 years), and accuracy provide a unique dataset for investigating snow processes. This presentation illustrates how the reanalysis dataset was used to provide a basic accounting of the stored snowpack water in the Sierra Nevada over the last 31 years and ultimately improve real-time streamflow predictions.

  19. Structural terranes and their relationships in Sierra Leone

    NASA Astrophysics Data System (ADS)

    Williams, Howard R.; Culver, Stephen J.

    Sierra Leone, composed mainly of Archaean granite-greenstone terrane, is bounded in the west by a westward dipping zone of intense, ductile, simple shear deformation which produced very fine-grained, high grade rocks. This zone has been interpreted as a possible Archaean suture developed following the collision of the Guyana Shield and the West African Craton. Granulite facies metamorphic supracrustals of the Kasila Group occur to the west of the sheared zone. Marampa Group lower grade metamorphics were thrust eastwards during the collision event. Late Precambrian rifting, well to the east of the mylonite zone and subsequent compression, preserved very low grade to unmetamorphosed Rokel River Group sediments and volcanics. Limited Pan-African tectonic transport of Archaean and late Precambrian material was again toward the east. All structural and stratigraphic units can be traced northward into Guinea where they disappear beneath the Paleozoic sediments of the Bové Basin. To the south, the Kasila Group, the granite-greenstone terrane and the mylonitized zone can be traced into Liberia. The Gibi Mountain Formation of Liberia is probably laterally equivalent to the lower portions of the Rokel River Group. This interpretation of the geology of Sierra Leone differs greatly from that of Guinea where the mylonitized zone, associated with a positive gravity anomaly, has been interpreted as a suture zone resulting from Pan-African continent-continent collision.

  20. Upper mantle anisotropic attenuation of the Sierra Nevada and surroundings

    NASA Astrophysics Data System (ADS)

    Bernardino, M. J.; Jones, C. H.; Monsalve, G.

    2016-12-01

    We investigate the contribution of anelasticity in the generation of seismic velocity variations within the upper mantle of the Sierra Nevada and surrounding regions through teleseismic shear-wave attenuation. Given that anelastic effects are most sensitive to temperature and hydration and less to composition and small degrees of partial melt, we aim constrain the thermal structure beneath this region and identify locations where elevated upper mantle temperatures dominate. We also investigate the dependence of shear-wave attenuation on direction by accounting for seismic anisotropy in our measurements. S-wave t* values are determined from teleseismic S- and SKS- phases recorded on permanent and temporary deployments within the California region with particular focus on the Sierra Nevada Earthscope Project (SNEP) and the Sierran Paradox Experiment (SPE) stations. S-waveforms are rotated into the Sierran SFast, N75°E, and SSlow, N15°W, components. Following the method of Stachnik et al., (2004), S-wave spectra for each event are jointly inverted for a single seismic moment, M0k, and corner frequency, fck, for each event, and separate t* for each ray path. The resulting t*Fast and t*Slow measurements are then inverted for three-dimensional variations in (1/QFast) and (1/QSlow). Results are compared with previous magnetotelluric, surface heat flow, and body-wave velocity inversion studies.

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

    NASA Astrophysics Data System (ADS)

    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

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

    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.

  3. Quantifying the Restorable Water Volume of California's Sierra Nevada Meadows

    NASA Astrophysics Data System (ADS)

    Emmons, J. D.; Yarnell, S. M.; Fryjoff-Hung, A.; Viers, J.

    2013-12-01

    The Sierra Nevada is estimated to provide over 66% of California's water supply, which is largely derived from snowmelt. Global climate warming is expected to result in a decrease in snow pack and an increase in melting rate, making the attenuation of snowmelt by any means, an important ecosystem service for ensuring water availability. Montane meadows are dispersed throughout the mountain range and can act like natural reservoirs, and also provide wildlife habitat, water filtration, and water storage. Despite the important role of meadows in the Sierra Nevada, a large proportion is degraded from stream incision, which increases volume outflows and reduces overbank flooding, thus reducing infiltration and potential water storage. Restoration of meadow stream channels would therefore improve hydrological functioning, including increased water storage. The potential water holding capacity of restored meadows has yet to be quantified, thus this research seeks to address this knowledge gap by estimating the restorable water volume due to stream incision. More than 17,000 meadows were analyzed by categorizing their erosion potential using channel slope and soil texture, ultimately resulting in six general erodibility types. Field measurements of over 100 meadows, stratified by latitude, elevation, and geologic substrate, were then taken and analyzed for each erodibility type to determine average depth of incision. Restorable water volume was then quantified as a function of water holding capacity of the soil, meadow area and incised depth. Total restorable water volume was found to be 120 x 10^6 m3, or approximately 97,000 acre-feet. Using 95% confidence intervals for incised depth, the upper and lower bounds of the total restorable water volume were found to be 107 - 140 x 10^6 m3. Though this estimate of restorable water volume is small in regards to the storage capacity of typical California reservoirs, restoration of Sierra Nevada meadows remains an important

  4. Contraception determinants in youths of Sierra Leone are largely behavioral.

    PubMed

    Labat, Aline; Medina, Marta; Elhassein, Mohammed; Karim, Afrina; Jalloh, Mohammad B; Dramaix, Michèle; Zhang, Wei-Hong; Alexander, Sophie; Dickson, Kim E

    2018-04-19

    Sexual initiation occurs early in Sierra Leone. This study aims to analyze the determinants of condom and/or contraceptive use among a representative sample of young persons (10 to 24 years) in Sierra Leone. This is a secondary analysis of data from a study conducted to monitor the implementation of a UNFPA package of interventions directed to improve SRH in young people of Sierra Leone. This assessment was conducted in 2016 at the end of the Ebola outbreak. In consequence, determinants linked to healthy lifestyle behaviors and UNFPA interventions were explored in addition to the usual determinants: socio demographic and sexual lifestyle. This study is a household quantitative survey with open ended questions used to illustrate and complete the analysis. A total of 1409 young people were interviewed: of these, 216 boys and 381 girls were sexually active. Those who were pregnant or wished for pregnancy were excluded, leaving 194 boys and 268 girls for the analysis of determinants. The proportion of young people using neither condom nor other contraception at their last sexual intercourse in the whole sample was 40.5% and there was no statistically significant difference between boys and girls (42.3 vs 39.2; P = 0.504). Determinants were assessed and, after multivariable analysis, results differed between boys and girls and showed the importance of behavioral aspects. Four determinants were common to boys and girls: literacy, distance, negotiation capacity and hand washing. However, the distance factor for girls was to the health facility and for boys it was to school. Three more determinants remained in the boy's model: sleeping under a bednet, number of sexual partners and knowledge of contraceptive methods. Opinions about condoms and contraception revealed important barriers; opposition to contraceptive use was the main reason for non-use for both boys and girls, while lack of access was an important reason for boys. There is a need to reach out to the 40% of

  5. Search for Gamma Ray Bursts at Sierra Negra, Mexico

    SciT

    Salazar, H.; Alvarez, C.; Martinez, O.

    2006-09-25

    We present results from a search for GRBs in the energy range from tens of GeVs to one TeV with an array of 4 water Cherenkov detectors located at 4550 m a.s.l. as part of the high mountain observatory of Sierra Negra (N18 deg. 59.1, W97 deg. 18.76) near Puebla city in Mexico. The detectors consist of light-tight cylindrical containers of 1 m2 and 4 m2 cross section filled with purified water; they are spaced 25 m and have a 5'' photomultiplier (EMI model 9030A) facing down along the cylindrical axis. We report the measured rates of the electromagnetic andmore » mounic components of the background as the photon estimated flux.« less

  6. Sierra Nevada Corporation's Dream Chaser Test Article Altitude T

    2017-08-30

    Sierra Nevada Corporation’s Dream Chaser completed an important step toward orbital flight with a successful captive carry test at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. A helicopter successfully carried a Dream Chaser test article, which has the same specifications as a flight-ready spacecraft, to the same altitude and flight conditions of an upcoming free flight test. The Dream Chaser is a lifting-body, winged spacecraft that will fly back to Earth in a manner similar to NASA’s space shuttles. The successful captive carry test clears the way for a free flight test of the spacecraft later this year in which the uncrewed Dream Chaser will be released to glide on its own and land.

  7. Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstron

    2017-01-25

    Sierra Nevada Corporation’s Dream Chaser spacecraft arrives by truck at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

  8. Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstrong

    2017-01-25

    Sierra Nevada Corporation’s Dream Chaser spacecraft arrives by truck at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

  9. Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstron

    2017-01-25

    Sierra Nevada Corporation’s Dream Chaser spacecraft is removed from its delivery truck after arriving at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

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

    SciT

    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 formore » each problem in order to facilitate element selection when computer resources are limited.« less

  11. Development of a Pediatric Ebola Predictive Score, Sierra Leone1.

    PubMed

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

    2018-02-01

    We compared children who were positive for Ebola virus disease (EVD) with those who were negative to derive a pediatric EVD predictor (PEP) score. We collected data on all children <13 years of age admitted to 11 Ebola holding units in Sierra Leone during August 2014-March 2015 and performed multivariable logistic regression. Among 1,054 children, 309 (29%) were EVD positive and 697 (66%) EVD negative, with 48 (5%) missing. Contact history, conjunctivitis, and age were the strongest positive predictors for EVD. The PEP score had an area under receiver operating characteristics curve of 0.80. A PEP score of 7/10 was 92% specific and 44% sensitive; 3/10 was 30% specific, 94% sensitive. The PEP score could correctly classify 79%-90% of children and could be used to facilitate triage into risk categories, depending on the sensitivity or specificity required.

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed Central

    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 <13 years old admitted to 11 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

  14. SIERRA Low Mach Module: Fuego User Manual Version 4.46.

    SciT

    Sierra Thermal/Fluid Team

    2017-09-01

    The SIERRA Low Mach Module: Fuego along with the SIERRA Participating Media Radiation Module: Syrinx, henceforth referred to as Fuego and Syrinx, respectively, are the key elements of the ASCI fire environment simulation project. The fire environment simulation project is directed at characterizing both open large-scale pool fires and building enclosure fires. Fuego represents the turbulent, buoyantly-driven incompressible flow, heat transfer, mass transfer, combustion, soot, and absorption coefficient model portion of the simulation software. Syrinx represents the participating-media thermal radiation mechanics. This project is an integral part of the SIERRA multi-mechanics software development project. Fuego depends heavily upon the coremore » architecture developments provided by SIERRA for massively parallel computing, solution adaptivity, and mechanics coupling on unstructured grids.« less

  15. California; Northern Sierra Air Quality Management District; Approval of Air Plan Revisions; Wood Burning Devices

    EPA Pesticide Factsheets

    EPA is taking final action to approve a revision to the Northern Sierra Air Quality Management District (NSAQMD) portion of the California SIP concerning emissions of particulate matter (PM) from wood burning devices.

  16. Soil acidity, temperature, and water relationships of four clovers in Sierra Nevada meadows

    Raymond D. Ratliff; Ethelynda E. Harding

    1993-01-01

    Sites in meadows of the Sierra Nevada near Fresno, California, were studied to learn whether Bolander's (Trifolium holanderi Gray.), longstalked (T. longipes Nutt.), carpet (T. monanthum Gray.), and mountain (T. wormskioldii Lehm.) clovers occurred under the same soil acidity, temperature...

  17. SIERRA Low Mach Module: Fuego Theory Manual Version 4.46.

    SciT

    Sierra Thermal/Fluid Team

    The SIERRA Low Mach Module: Fuego along with the SIERRA Participating Media Radiation Module: Syrinx, henceforth referred to as Fuego and Syrinx, respectively, are the key elements of the ASCI fire environment simulation project. The fire environment simulation project is directed at characterizing both open large-scale pool fires and building enclosure fires. Fuego represents the turbulent, buoyantly-driven incompressible flow, heat transfer, mass transfer, combustion, soot, and absorption coefficient model portion of the simulation software. Syrinx represents the participating-media thermal radiation mechanics. This project is an integral part of the SIERRA multi-mechanics software development project. Fuego depends heavily upon the coremore » architecture developments provided by SIERRA for massively parallel computing, solution adaptivity, and mechanics coupling on unstructured grids.« less

  18. SIERRA Low Mach Module: Fuego Theory Manual Version 4.44

    SciT

    Sierra Thermal /Fluid Team

    2017-04-01

    The SIERRA Low Mach Module: Fuego along with the SIERRA Participating Media Radiation Module: Syrinx, henceforth referred to as Fuego and Syrinx, respectively, are the key elements of the ASCI fire environment simulation project. The fire environment simulation project is directed at characterizing both open large-scale pool fires and building enclosure fires. Fuego represents the turbulent, buoyantly-driven incompressible flow, heat transfer, mass transfer, combustion, soot, and absorption coefficient model portion of the simulation software. Syrinx represents the participating-media thermal radiation mechanics. This project is an integral part of the SIERRA multi-mechanics software development project. Fuego depends heavily upon the coremore » architecture developments provided by SIERRA for massively parallel computing, solution adaptivity, and mechanics coupling on unstructured grids.« less

  19. Magnetic and gravity anomalies in the Sierra del Padre and Sierra del Tala, San Luis Province, Argentina: evidence of buried mafic ultramafic rocks

    NASA Astrophysics Data System (ADS)

    Kostadinoff, José; Alfredo Bjerg, Ernesto; Gregori, Daniel; Delpino, Sergio; Dimieri, Luis; Raniolo, Ariel; Mogessie, Aberra; Hoinkes, Georg; Hauzenberger, Christoph; Felfernig, Anja

    2001-07-01

    This paper presents the results of a geophysical study of the southern portion of the Sierra Grande de San Luis, San Luis Province, Argentina. A 26 mGal amplitude Bouguer anomaly (Charlone anomaly), measuring 40 km long by 7 km wide, between Sierra de los Padres and Zanjitas reflects the presence of high-density rocks located at approximately 2000 m depth. Geophysical models based on more than 300 gravimetric, magnetometric, and geological field measurements and observations suggest that the mafic-ultramafic belt of Sierra Grande de San Luis continues south of San Luis. The low magnitude of the terrestrial magnetic field anomalies indicates that these mafic-ultramafic rocks do not carry a base metal sulfides (BMS) mineralization. The Charlone gravimetric anomaly is generated by a belt of mafic- ultramafic rocks whose amplitude is comparable with that responsible for the Virorco-Las Aguilas gravimetric anomaly.

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

    NASA Astrophysics Data System (ADS)

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

    2017-09-01

    Systematic 40Ar/39Ar feldspar data obtained from the Sierras Pampeanas are presented, filling the gap between available high- (> 300 °C) and low-temperature (< 150 °C) thermochronological data. Results show Silurian-Devonian exhumation related to the late stages of the Famatinian/Ocloyic Orogeny for the Sierra de Pocho and the Sierra de 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.

  1. The metamorphic basement of the southern Sierra de Aconquija, Eastern Sierras Pampeanas: Provenance and tectonic setting of a Neoproterozoic back-arc basin

    NASA Astrophysics Data System (ADS)

    Cisterna, Clara Eugenia; Altenberger, Uwe; Mon, Ricardo; Günter, Christina; Gutiérrez, Antonio

    2018-03-01

    The Eastern Sierras Pampeanas are mainly composed of Neoproterozoic-early Palaeozoic metamorphic complexes whose protoliths were sedimentary sequences deposited along the western margin of Gondwana. South of the Sierra de Aconquija, Eastern Sierras Pampeanas, a voluminous metamorphic complex crops out. It is mainly composed of schists, gneisses, marbles, calk-silicate schists, thin layers of amphibolites intercalated with the marbles and granitic veins. The new data correlate the Sierra de Aconquija with others metamorphic units that crop out to the south, at the middle portion of the Sierra de Ancasti. Bulk rock composition reflects originally shales, iron rich shales, wackes, minor litharenites and impure limestones as its protoliths. Moreover, comparisons with the northern Sierra de Aconquija and from La Majada (Sierra de Ancasti) show similar composition. Amphibolites have a basaltic precursor, like those from the La Majada (Sierra de Ancasti) ones. The analyzed metamorphic sequence reflects low to moderate weathering conditions in the sediments source environment and their chemical composition would be mainly controlled by the tectonic setting of the sedimentary basin rather than by the secondary sorting and reworking of older deposits. The sediments composition reveal relatively low maturity, nevertheless the Fe - shale and the litharenite show a tendency of minor maturity among them. The source is related to an acid one for the litharenite protolith and a more basic to intermediate for the other rocks, suggesting a main derivation from intermediate to felsic orogen. The source of the Fe-shales may be related to and admixture of the sediments with basic components. Overall the composition point to an upper continental crust as the dominant sediment source for most of the metasedimentary rocks. The protolith of the amphibolites have basic precursors, related to an evolving back-arc basin. The chemical data in combination with the specific sediment association

  2. South African Ebola diagnostic response in Sierra Leone: A modular high biosafety field laboratory

    PubMed Central

    Jansen van Vuren, Petrus; Meier, Gunther H.; le Roux, Chantel; Conteh, Ousman S.; Kemp, Alan; Fourie, Cardia; Naidoo, Prabha; Naicker, Serisha; Ohaebosim, Phumza; Storm, Nadia; Hellferscee, Orienka; Ming Sun, Lisa K.; Mogodi, Busisiwe; Prabdial-Sing, Nishi; du Plessis, Desiree; Greyling, Deidre; Loubser, Shayne; Goosen, Mark; McCulloch, Stewart D.; Scott, Terence P.; Moerdyk, Alexandra; Dlamini, Wesley; Konneh, Kelfala; Kamara, Idrissa L.; Sowa, Dauda; Sorie, Samuel; Kargbo, Brima; Madhi, Shabir A.

    2017-01-01

    Background In August 2014, the National Institute for Communicable Diseases (NICD) in South Africa established a modular high-biosafety field Ebola diagnostic laboratory (SA FEDL) near Freetown, Sierra Leone in response to the rapidly increasing number of Ebola virus disease (EVD) cases. Methods and findings The SA FEDL operated in the Western Area of Sierra Leone, which remained a “hotspot” of the EVD epidemic for months. The FEDL was the only diagnostic capacity available to respond to the overwhelming demand for rapid EVD laboratory diagnosis for several weeks in the initial stages of the EVD crisis in the capital of Sierra Leone. Furthermore, the NICD set out to establish local capacity amongst Sierra Leonean nationals in all aspects of the FEDL functions from the outset. This led to the successful hand-over of the FEDL to the Sierra Leone Ministry of Health and Sanitation in March 2015. Between 25 August 2014 and 22 June 2016, the laboratory tested 11,250 specimens mostly from the Western Urban and Western Rural regions of Sierra Leone, of which 2,379 (21.14%) tested positive for Ebola virus RNA. Conclusions The bio-safety standards and the portability of the SA FEDL, offered a cost-effective and practical alternative for the rapid deployment of a field-operated high biocontainment facility. The SA FEDL teams demonstrated that it is highly beneficial to train the national staff in the course of formidable disease outbreak and accomplished their full integration into all operational and diagnostic aspects of the laboratory. This initiative contributed to the international efforts in bringing the EVD outbreak under control in Sierra Leone, as well as capacitating local African scientists and technologists to respond to diagnostic needs that might be required in future outbreaks of highly contagious pathogens. PMID:28628619

  3. South African Ebola diagnostic response in Sierra Leone: A modular high biosafety field laboratory.

    PubMed

    Paweska, Janusz T; Jansen van Vuren, Petrus; Meier, Gunther H; le Roux, Chantel; Conteh, Ousman S; Kemp, Alan; Fourie, Cardia; Naidoo, Prabha; Naicker, Serisha; Ohaebosim, Phumza; Storm, Nadia; Hellferscee, Orienka; Ming Sun, Lisa K; Mogodi, Busisiwe; Prabdial-Sing, Nishi; du Plessis, Desiree; Greyling, Deidre; Loubser, Shayne; Goosen, Mark; McCulloch, Stewart D; Scott, Terence P; Moerdyk, Alexandra; Dlamini, Wesley; Konneh, Kelfala; Kamara, Idrissa L; Sowa, Dauda; Sorie, Samuel; Kargbo, Brima; Madhi, Shabir A

    2017-06-01

    In August 2014, the National Institute for Communicable Diseases (NICD) in South Africa established a modular high-biosafety field Ebola diagnostic laboratory (SA FEDL) near Freetown, Sierra Leone in response to the rapidly increasing number of Ebola virus disease (EVD) cases. The SA FEDL operated in the Western Area of Sierra Leone, which remained a "hotspot" of the EVD epidemic for months. The FEDL was the only diagnostic capacity available to respond to the overwhelming demand for rapid EVD laboratory diagnosis for several weeks in the initial stages of the EVD crisis in the capital of Sierra Leone. Furthermore, the NICD set out to establish local capacity amongst Sierra Leonean nationals in all aspects of the FEDL functions from the outset. This led to the successful hand-over of the FEDL to the Sierra Leone Ministry of Health and Sanitation in March 2015. Between 25 August 2014 and 22 June 2016, the laboratory tested 11,250 specimens mostly from the Western Urban and Western Rural regions of Sierra Leone, of which 2,379 (21.14%) tested positive for Ebola virus RNA. The bio-safety standards and the portability of the SA FEDL, offered a cost-effective and practical alternative for the rapid deployment of a field-operated high biocontainment facility. The SA FEDL teams demonstrated that it is highly beneficial to train the national staff in the course of formidable disease outbreak and accomplished their full integration into all operational and diagnostic aspects of the laboratory. This initiative contributed to the international efforts in bringing the EVD outbreak under control in Sierra Leone, as well as capacitating local African scientists and technologists to respond to diagnostic needs that might be required in future outbreaks of highly contagious pathogens.

  4. Gas geochemistry of Sierra Negra volcano, Galapagos hot spot

    NASA Astrophysics Data System (ADS)

    Taran, Y.; Christenson, B.; Sumino, H.; Kennedy, B.

    2010-12-01

    We report chemical and isotopic compositions of gases from the Mina Azufral fumarolic field of Sierra Negra volcano, Isabela Island, Galápagos, collected in 2004 and compare our data with the data by Giggenbach (unpublished) collected in 1990 and Goff et al. (2000) collected in 1995. New results include the noble gas elemental and isotope abundances and nitrogen isotope ratios for the discharges. Maximum fumarole temperatures and ratios of major components (C/S/Cl/N) changed very little between 1995 and 2004, but the water fraction varied significantly over this period (39 mol% in 1990; 77% in 1995 and 52% in 2004). Carbon and helium isotopic compositions were stable (-3 to -4‰ and 16-18Ra, respectively), and water isotopic composition showed a notable negative oxygen shift from the local meteoric water value depending on the relative water content and thus controlled by the H2O-CO2 oxygen isotope fractionation. In terms of the noble gas abundances and isotopic ratios, heavy noble gases (Kr and Xe) are mainly of the atmospheric origin. Ne isotopic ratios also show strong meteoric signatures, but fall along the 20Ne/22Ne - 21Ne/22Ne air-deep mantle mixing trend for Fernandina glasses (Kurz et al., 2009). 40Ar/36Ar ratios up to 400 show a notable contribution of radiogenic Ar, and 40Ar*/4He ~ 0.3 ratios are consistent with un-degassed upper mantle values. Despite the high He/Ne ratios in gases collected in 2004, and only trace air contamination attributable to sampling, the nitrogen isotope ratios (~ -1 ‰) show a high fraction of the air-saturated water in the volcanic vapor. The chemical composition of the parent magmatic gas is difficult to characterise due to significant interaction between magmatic and hydrothermal system fluids beneath the Sierra Negra caldera. Never-the-less, some important indicators can be estimated: CO2/3He ≈ 3.5x10^9; N2/He <30; CO2/N2 >500. The last value is much higher than the accepted value of ~ 100 for the upper mantle.

  5. SIERRA Multimechanics Module: Aria User Manual Version 4.44

    SciT

    Sierra Thermal /Fluid Team

    2017-04-01

    Aria is a Galerkin fnite 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 fows via the incompressible Navier-Stokes equations specialized to a low Reynolds number ( %3C 1 ) regime. Enhanced modeling support of manufacturing processing is made possible through use of eithermore » 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.« less

  6. LANDSAT-D investigations in snow hydrology. [Sierra Nevada Mountains

    NASA Technical Reports Server (NTRS)

    Dozier, J.

    1983-01-01

    Thematic mapper data for the southern Sierra Nevada area were registered to digital topographic data and compared to LANDSAT MSS and NOAA-7 AVHRR data of snow covered areas in order to determine the errors associated with using coarser resolution and to qualify the information lost when high resolution data are not available. Both the zenith and the azimuth variations in the radiative field are considered in an atmospheric radiative transfer model which deals with a plane parallel structured atmosphere composed of different layers, each assumed to be homogeneous in composition and to have a linear in tau temperature profile. Astronomical parameters for each layer are Earth-Sun distance and solar flux at the top of the atmosphere. Atmospheric parameters include pressure temperature, chemical composition of the air molecules, and the composition and size of the aerosol, water droplets, and ice crystals. Outputs of the model are the monochromatic radiance and irradiance at each level. The use of the model in atmospheric correction of remotely sensed data is discussed.

  7. Sierra Stars Observatory Network: An Accessible Global Network

    NASA Astrophysics Data System (ADS)

    Williams, Richard; Beshore, Edward

    2011-03-01

    The Sierra Stars Observatory Network (SSON) is a unique partnership among professional observatories that provides its users with affordable high-quality calibrated image data. SSON comprises observatories in the Northern and Southern Hemisphere and is in the process of expanding to a truly global network capable of covering the entire sky 24 hours a day in the near future. The goal of SSON is to serve the needs of science-based projects and programs. Colleges, universities, institutions, and individuals use SSON for their education and research projects. The mission of SSON is to promote and expand the use of its facilities among the thousands of colleges and schools worldwide that do not have access to professional-quality automated observatory systems to use for astronomy education and research. With appropriate leadership and guidance educators can use SSON to help teach astronomy and do meaningful scientific projects. The relatively small cost of using SSON for this type of work makes it affordable and accessible for educators to start using immediately. Remote observatory services like SSON need to evolve to better support education and research initiatives of colleges, institutions and individual investigators. To meet these needs, SSON is developing a sophisticated interactive scheduling system to integrate among the nodes of the observatory network. This will enable more dynamic observations, including immediate priority interrupts, acquiring moving objects using ephemeris data, and more.

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

    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.

  9. Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016

    PubMed Central

    Scott, Janet T.; Baxter, Julia M.; Parkes, Craig K.; Dwivedi, Rahul; Czanner, Gabriela; Vandy, Matthew J.; Momorie, Fayiah; Fornah, Alimamy D.; Komba, Patrick; Richards, Jade; Sahr, Foday; Beare, Nicholas A.V.; Semple, Malcolm G.

    2017-01-01

    We conducted a case–control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors. A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging. Snellen visual acuity was <6/7.5 in 75.6% (97.5% CI 63%–85.7%) of EVD survivors and 75.5% (97.5% CI 59.1%–87.9%) of controls. Unilateral white cataracts were present in 7.4% (97.5% CI 2.4%–16.7%) of EVD survivors and no controls. Aqueous humor from 2 EVD survivors with cataract but no anterior chamber inflammation were PCR-negative for Zaire Ebola virus, permitting cataract surgery. A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%–25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry. PMID:28628441

  10. The saltiest springs in the Sierra Nevada, California

    Moore, James G.; Diggles, Michael F.; Evans, William C.; Klemic, Karin

    2017-07-20

    The five saltiest springs in the Sierra Nevada in California are found between 38.5° and 38.8° N. latitude, on the South Fork American River; on Caples Creek, a tributary of the Silver Fork American River; and on the North Fork Mokelumne River. The springs issue from Cretaceous granitic rocks in the bottoms of these major canyons, between 1,200- and 2,200-m elevation. All of these springs were well known to Native Americans, who excavated meter-sized basins in the granitic rock, within which they produced salt by evaporation near at least four of the five spring sites. The spring waters are dominated by Cl, Na, and Ca; are enriched relative to seawater in Ca, Li, and As; and are depleted in SO4, Mg, and K. Tritium analyses indicate that the spring waters have had little interaction with rainfall since about 1954. The waters are apparently an old groundwater of meteoric origin that resided at depth before moving up along fractures to the surface of the exhumed granitic rocks. However, along the way these waters incorporated salts from depth, the origin of which could have been either from marine sedimentary rocks intruded by the granitic magmas or from fluid inclusions in the granitic rocks. Prolonged storage at depth fostered water-rock interactions that undoubtedly modified the fluid compositions.

  11. Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016.

    PubMed

    Steptoe, Paul J; Scott, Janet T; Baxter, Julia M; Parkes, Craig K; Dwivedi, Rahul; Czanner, Gabriela; Vandy, Matthew J; Momorie, Fayiah; Fornah, Alimamy D; Komba, Patrick; Richards, Jade; Sahr, Foday; Beare, Nicholas A V; Semple, Malcolm G

    2017-07-01

    We conducted a case-control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors. A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging. Snellen visual acuity was <6/7.5 in 75.6% (97.5% CI 63%-85.7%) of EVD survivors and 75.5% (97.5% CI 59.1%-87.9%) of controls. Unilateral white cataracts were present in 7.4% (97.5% CI 2.4%-16.7%) of EVD survivors and no controls. Aqueous humor from 2 EVD survivors with cataract but no anterior chamber inflammation were PCR-negative for Zaire Ebola virus, permitting cataract surgery. A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%-25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry.

  12. Hot springs of the central Sierra Nevada, California

    Mariner, R.H.; Presser, T.S.; Evans, William C.

    1977-01-01

    Thermal springs of the central Sierra Nevada issue dilute to slightly saline sodium chloride, sodium bicarbonate, or sodium mixed-anion waters ranging in pH from 6.4 to 9.3. The solubility of chalcedony appears to control the silica concentration in most of the spring waters. Fales Hot Springs may be associated with a higher temperature aquifer, 150 degrees Celsius or more, in which quartz is controlling the silica concentration. Carbon dioxide is the predominant gas escaping from Fales Hot Springs, the unnamed hot spring on the south side of Mono Lake, and the two thermal springs near Bridgeport. Most of the other thermal springs issue small amounts of gas consisting principally of nitrogen. Methane is the major component of the gas escaping from the unnamed spring on Paoha Island in Mono Lake. The deuterium and oxygen isotopic composition of most of the thermal waters are those expected for local meteoric water which has undergone minor water-rock reaction. The only exceptions are the hot spring on Paoha Island in Mono Lake and perhaps the unnamed warm spring (south side of Mono Lake) which issues mixtures of thermal water and saline lake water. (Woodard-USGS)

  13. Reading between the lines: Societal norms in Sierra Leonean readers

    NASA Astrophysics Data System (ADS)

    Brams, Patricia

    1980-12-01

    A content analysis of primary school readers of Sierra Leone revealed that the particular modern and traditional normative aspirations expressed in the National Development Plan for 1974/75-1978/79 were also generally reflected in the children's readers. Compared to the 1964 readers, the first indigenous readers developed circa 1977 contained markedly greater emphasis on traditional norms, though modernity norms continued to dominate, and substantially less emphasis on Efficacy (a central aspect of modernity) and on Non-parochial Affiliation. This closely corresponded with the intent of the National Plan to continue on a modernizing course employing the traditional norms of Manual Labor and Social Cohesion in a grassroots effort to develop the agricultural sector, with nationalism in a less important role. Apart from lesser emphasis on Efficacy and underemphasis on the Value of Education which were discordant with national goals, the 1977 readers seem to provide children and teachers with a fairly accurate image of the national ethos. This may help to account for the generally positive relationship that has been found between schooling and economic development.

  14. Seed germination of Sierra Nevada postfire chaparral species

    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.

  15. Photo series for quantifying forest fuels in Mexico: montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental

    Jorge E. Morfin-Rios; Ernesto Alvarado-Celestino; Enrique J. Jardel-Pelaez; Robert E. Vihnanek; David K. Wright; Jose M. Michel-Fuentes; Clinton S. Wright; Roger D. Ottmar; David V. Sandberg; Andres Najera-Diaz

    2008-01-01

    Single wide-angle and stereo photographs display a range of forest ecosystems conditions and fuel loadings in montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental of Mexico. Each group of photographs includes inventory information summarizing overstory vegetation composition and...

  16. Geology of the Sierra de Fiambala, northwestern Argentina: implications for Early Palaeozoic Andean tectonics

    Grissom, G.C.; DeBari, S.M.; Snee, L.W.

    1998-01-01

    This paper is included in the Special Publication entitled 'The proto- Andean margin of Gondwana', edited by R.J. Pankhurst and C.W. Rapela. Field mapping in conjunction with structural, metamorphic, and geochronological data document the tectono-thermal history of exhumed deep crustal rocks in the Sierra de Fiambala, NW Argentina. The range consists of two structural blocks distinguished by different metasedimentary sequences and different grades of metamorphism. Orthogneiss and paragneiss in the northern structural block may have a Precambrian history. Greenschist- to amphibolite-facies metamorphism, intrusion, and injection magmatization affected all rocks at 540-550 Ma. A subsequent event in the Late Cambrian to Ordovician (c.515 to 470 Ma) involved amphibolite- to granulite-facies metamorphism, mafic intrusion, and deformation, followed by cooling through mid-Palaeozoic time. The emplacement of Carboniferous (325-350 Ma) post-tectonic granites caused reheating and retrogression that was strongest toward the northeast part of the range. The Cambrian, Ordovician, and Carboniferous events in the Sierra de Fiambala were of regional extent as indicated by temporal correlations with events reported for other deep crustal rocks of the northern Sierras Pampeanas. Correlations between periods of intrusion and high-grade metamorphism in the northern Sierras Pampeanas and volcanic-sedimentary events in the adjacent supracrustal exposures confirm that rocks in the northern Sierras Pampeanas formed at deep (10-25 km) structural levels in the early Palaeozoic continental margin of Gondwana.

  17. Sinfonevada: Dataset of Floristic diversity in Sierra Nevada forests (SE Spain)

    PubMed Central

    Pérez-Luque, Antonio Jesús; Bonet, Francisco Javier; Pérez-Pérez, Ramón; Rut Aspizua; Lorite, Juan; Zamora, Regino

    2014-01-01

    Abstract The Sinfonevada database is a forest inventory that contains information on the forest ecosystem in the Sierra Nevada mountains (SE Spain). The Sinfonevada dataset contains more than 7,500 occurrence records belonging to 270 taxa (24 of these threatened) from floristic inventories of the Sinfonevada Forest inventory. Expert field workers collected the information. The whole dataset underwent a quality control by botanists with broad expertise in Sierra Nevada flora. This floristic inventory was created to gather useful information for the proper management of Pinus plantations in Sierra Nevada. This is the only dataset that shows a comprehensive view of the forest flora in Sierra Nevada. This is the reason why it is being used to assess the biodiversity in the very dense pine plantations on this massif. With this dataset, managers have improved their ability to decide where to apply forest treatments in order to avoid biodiversity loss. The dataset forms part of 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:24843285

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

    EPA Science Inventory

    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...

  19. Three-dimensional crustal structure of the southern Sierra Nevada from seismic fan profiles and gravity modeling

    Fliedner, M.M.; Ruppert, S.; Malin, P.E.; Park, S.K.; Jiracek, G.; Phinney, R.A.; Saleeby, J.B.; Wernicke, B.; Clayton, R.; Keller, Rebecca Hylton; Miller, K.; Jones, C.; Luetgert, J.H.; Mooney, W.D.; Oliver, H.; Klemperer, S.L.; Thompson, G.A.

    1996-01-01

    Traveltime data from the 1993 Southern Sierra Nevada Continental Dynamics seismic refraction experiment reveal low crustal velocities in the southern Sierra Nevada and Basin and Range province of California (6.0 to 6.6 km/s), as well as low upper mantle velocities (7.6 to 7.8 km/s). The crust thickens from southeast to northwest along the axis of the Sierra Nevada from 27 km in the Mojave Desert to 43 km near Fresno, California. A crustal welt is present beneath the Sierra Nevada, but the deepest Moho is found under the western slopes, not beneath the highest topography. A density model directly derived from the crustal velocity model but with constant mantle density satisfies the pronounced negative Bouguer anomaly associated with the Sierra Nevada, but shows large discrepancies of >50 mgal in the Great Valley and in the Basin and Range province. Matching the observed gravity with anomalies in the crust alone is not possible with geologically reasonable densities; we require a contribution from the upper mantle, either by lateral density variations or by a thinning of the lithosphere under the Sierra Nevada and the Basin and Range province. Such a model is consistent with the interpretation that the uplift of the present Sierra Nevada is caused and dynamically supported by asthenospheric upwelling or lithospheric thinning under the Basin and Range province and eastern Sierra Nevada.

  20. 77 FR 23476 - Energia Sierra Juarez U.S., LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-19

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER12-1470-000] Energia Sierra Juarez U.S., LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for... Energia Sierra Juarez U.S., LLC's application for market-based rate authority, with an accompanying rate...

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

    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.

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

    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.

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

    PubMed

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

    2016-01-01

    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.

  4. Tectonic, volcanic, and climatic geomorphology study of the Sierras Pampeanas Andes, northwestern Argentina

    NASA Technical Reports Server (NTRS)

    Bloom, A. L.; Strecker, M. R.; Fielding, E. J.

    1984-01-01

    A proposed analysis of Shuttle Imaging Radar-B (SIR-B) data extends current research in the Sierras Pampeanas and the Puna of northwestern Argentina to the determination - by the digital analysis of mountain-front sinuousity - of the relative age and amount of fault movement along mountain fronts of the late-Cenozoic Sierras Pampeanas basement blocks; the determination of the age and history of the boundary across the Andes at about 27 S latitude between continuing volcanism to the north and inactive volcanism to the south; and the determination of the age and extent of Pleistocene glaciation in the High Sierras, as well as the comparative importance of climatic change and tectonic movements in shaping the landscape. The integration of these studies into other ongoing geology projects contributes to the understanding of landform development in this active tectonic environment and helps distinguish between climatic and tectonic effects on landforms.

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

    PubMed Central

    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

  6. The Met Needs for Pediatric Surgical Conditions in Sierra Leone: Estimating the Gap.

    PubMed

    Burgos, Carmen Mesas; Bolkan, Håkon Angell; Bash-Taqi, Donald; Hagander, Lars; Von Screeb, Johan

    2018-03-01

    In low- and middle-income countries, there is a gap between the need for surgery and its equitable provision, and a lack of proxy indicators to estimate this gap. Sierra Leone is a West African country with close to three million children. It is unknown to what extent the surgical needs of these children are met. To describe a nationwide provision of pediatric surgical procedures and to assess pediatric hernia repair as a proxy indicator for the shortage of surgical care in the pediatric population in Sierra Leone. We analyzed results from a nationwide facility survey in Sierra Leone that collected data on surgical procedures from operation and anesthesia logbooks in all facilities performing surgery. We included data on all patients under the age of 16 years undergoing surgery. Primary outcomes were rate and volume of surgical procedures. We calculated the expected number of inguinal hernia in children and estimated the unmet need for hernia repair. In 2012, a total of 2381 pediatric surgical procedures were performed in Sierra Leone. The rate of pediatric surgical procedures was 84 per 100,000 children 0-15 years of age. The most common pediatric surgical procedure was hernia repair (18%), corresponding to a rate of 16 per 100,000 children 0-15 years of age. The estimated unmet need for inguinal hernia repair was 88%. The rate of pediatric surgery in Sierra Leone was very low, and inguinal hernia was the single most common procedure noted among children in Sierra Leone.

  7. Seismic character of the crust and upper mantle beneath the Sierra Nevada

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    Recent geophysical studies of the Southern Sierra Nevada suggest that the removal of a gravitationally unstable, eclogitic residue links to recent volcanism and uplift in the Eastern Sierra. The Sierra Nevada EarthScope Project (SNEP) investigates the extent of this process beneath Central and Northern Sierra Nevada. We present receiver functions, which provide estimates of crustal thickness and Vp/Vs and image the response of the crust and upper mantle to lithospheric removal. For completeness this study combines data from the 2005-2007 SNEP broadband experiment, EarthScope's BigFoot Array, regional backbone stations, and earlier PASSCAL deployments. We analyze transects of teleseismic receiver functions generated using a common-conversion-point stacking algorithm. These identify a narrow, "bright" conversion from the Moho at depths of ~25-35 km along the crest of the Eastern Sierra and adjacent Basin and Range northward to the Cascade Arc. Trade-off analysis using the primary conversion and reverberations shows a high Vp/Vs (~1.9) throughout the Eastern Sierra, which may relate to partial melt present in the lower crust. To the west the crust-mantle boundary vanishes beneath the western foothills. However, low frequency receiver functions do image the crust-mantle boundary exceeding 50 km depth along the foothills to the west and south of Yosemite National Park. Unusually deep, intraplate earthquakes (Ryan et al., this session) occur in the center of this region. The frequency dependence of the Moho conversion implies a gradational increase from crust to mantle wavespeeds over a significant depth interval. The transition from a sharp to gradational Moho probably relates to the change from a delaminated granitic crust to crust with an intact, dense, eclogitic residue. The spatial correlation and focal mechanisms of the deep earthquakes suggest that a segment of this still intact residue is currently delaminating.

  8. Semiarid ethnoagroforestry management: Tajos in the Sierra Gorda, Guanajuato, Mexico.

    PubMed

    Hoogesteger van Dijk, Vincent M; Casas, Alejandro; Moreno-Calles, Ana Isabel

    2017-06-12

    The semi-arid environments harbor nearly 40% of biodiversity, and half of indigenous cultures of Mexico. Thousands of communities settled in these areas depend on agriculture and using wild biodiversity for their subsistence. Water, soil, and biodiversity management strategies are therefore crucial for people's life. The tajos, from Sierra Gorda, are important, poorly studied, biocultural systems established in narrow, arid alluvial valleys. The systems are constructed with stone-walls for capturing sediments, gradually creating fertile soils in terraces suitable for agriculture in places where it would not be possible. We analyzed biocultural, ecological, economic and technological relevance of the artificial oasis-like tajos, hypothesizing their high capacity for maintaining agricultural and wild biodiversity while providing resources to people. We conducted our research in three sections of the Mezquital-Xichú River, in three communities of Guanajuato, Mexico. Agroforestry management practices were documented through semi-structured and in-depth qualitative interviews. Vegetation composition of local forests and that maintained in tajos was sampled and compared. Tajos harbor high agrobiodiversity, including native varieties of maize and beans, seven secondary crops, 47 native and 25 introduced perennial plant species. Perennial plants cover on average 26.8% of the total surface of plots. Tajos provide nearly 70% of the products required by households' subsistence and are part of their cultural identity. Tajos are heritage of TEK and land management forms of pre-Columbian Mexican and Mediterranean agricultural techniques, adapting and integrating modern agricultural practices. Tajos are valuable biocultural systems adapted to local semiarid conditions and sources of technology for similar areas of the World.

  9. Chronology for fluctuations in late Pleistocene Sierra Nevada glaciers and lakes

    Phillips, F.M.; Zreda, M.G.; Benson, L.V.; Plummer, M.A.; Elmore, D.; Sharma, Prakash

    1996-01-01

    Mountain glaciers, because of their small size, are usually close to equilibrium with the local climate and thus should provide a test of whether temperature oscillations in Greenland late in the last glacial period are part of global-scale climate variability or are restricted to the North Atlantic region. Correlation of cosmogenic chlorine-36 dates on Sierra Nevada moraines with a continuous radiocarbon-dated sediment record from nearby Owens Lake shows that Sierra Nevada glacial advances were associated with Heinrich events 5, 3, 2, and 1.

  10. Insights on Lithospheric Foundering from the Sierra Nevada Earthscope Project (SNEP)

    NASA Astrophysics Data System (ADS)

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

    2004-12-01

    Interdisciplinary studies in the southern Sierra Nevada have documented an ongoing removal of the dense residual root from beneath the southern Sierra Nevada batholith. However, many questions remain concerning the timing, spatial extent, mechanism, and consequences of this lithospheric foundering event. The Sierra Nevada Earthscope Project (SNEP) is a scientific experiment designed to investigate these questions with a 2- phase (2 year) seismic deployment of 46 broadband Flex-Array stations embedded in the existing stations of the USArray Transportable Array (TA) in the region. In the 2 phases, approximately 80 sites have been occupied from the northern edge of Kings Canyon north to Honey Lake and from the Central Valley into the Great Basin. In this presentation, we will focus on the most recent common-conversion-point (CCP) stacks of the receiver functions that provide a 3D image of lithospheric layering beneath the central and northern Sierra Nevada. Examining sequential cross-sections reveals distinctive lithospheric "reflectivity" patterns that characterize different tectonic imprints. From phase 1 data, we observed that the westernmost Basin and Range exhibits strong layering with multiple low-velocity zones in the crust and uppermost mantle and a relatively flat and strong Moho varying slowly in depth between 30 and 35 km. In the south this Basin and Range character terminates on the eastern edge of the Sierra Nevada; however, north of Big Pine the Basin and Range character intrudes progressively farther into the range and ends up more than 50 km west of the eastern edge of the range. The lithosphere beneath the southern high Sierra Nevada is characterized by a relatively transparent (homogeneous) crust and sharp Moho that disappears westward beneath the adjacent foothills. The crustal thickness in this area is mostly between 30-35 km with localized welts of thicker crust. The phase 1 observations imply that the removal process appears to be actively

  11. Insights on Lithospheric Foundering from the Sierra Nevada Earthscope Project (SNEP)

    NASA Astrophysics Data System (ADS)

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

    2007-12-01

    Interdisciplinary studies in the southern Sierra Nevada have documented an ongoing removal of the dense residual root from beneath the southern Sierra Nevada batholith. However, many questions remain concerning the timing, spatial extent, mechanism, and consequences of this lithospheric foundering event. The Sierra Nevada Earthscope Project (SNEP) is a scientific experiment designed to investigate these questions with a 2- phase (2 year) seismic deployment of 46 broadband Flex-Array stations embedded in the existing stations of the USArray Transportable Array (TA) in the region. In the 2 phases, approximately 80 sites have been occupied from the northern edge of Kings Canyon north to Honey Lake and from the Central Valley into the Great Basin. In this presentation, we will focus on the most recent common-conversion-point (CCP) stacks of the receiver functions that provide a 3D image of lithospheric layering beneath the central and northern Sierra Nevada. Examining sequential cross-sections reveals distinctive lithospheric "reflectivity" patterns that characterize different tectonic imprints. From phase 1 data, we observed that the westernmost Basin and Range exhibits strong layering with multiple low-velocity zones in the crust and uppermost mantle and a relatively flat and strong Moho varying slowly in depth between 30 and 35 km. In the south this Basin and Range character terminates on the eastern edge of the Sierra Nevada; however, north of Big Pine the Basin and Range character intrudes progressively farther into the range and ends up more than 50 km west of the eastern edge of the range. The lithosphere beneath the southern high Sierra Nevada is characterized by a relatively transparent (homogeneous) crust and sharp Moho that disappears westward beneath the adjacent foothills. The crustal thickness in this area is mostly between 30-35 km with localized welts of thicker crust. The phase 1 observations imply that the removal process appears to be actively

  12. Surface uplift and atmospheric flow deflection in the Late Cenozoic southern Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Mix, H.; Caves, J. K.; Winnick, M.; Ritch, A. J.; Reilly, S.; Chamberlain, C. P.

    2016-12-01

    Given the intimate links between topography, tectonics, climate and biodiversity, considerable effort has been devoted to developing robust elevation histories of orogens. In particular, quantitative geochemical reconstructions using stable oxygen and hydrogen isotopes have been applied to many of the world's mountain belts. Yet after decades of study, determining the Cenozoic surface uplift history of the Sierra Nevada remains a challenge. While geological and geophysical evidence suggests the southern Sierra underwent 1-2 km of Late Cenozoic surface uplift, stable isotope paleoaltimetry studies to date have been restricted to the Basin and Range interior. Recent advances in atmospheric modeling have suggested that such stable isotope records from leeward sites can be affected by the complicating role that sufficiently elevated topography such as the southern (High) Sierra plays in diverting atmospheric circulation. In order to examine the potential role of these terrain blocking effects, we produced stable isotope records from three Late Cenozoic sedimentary basins in the Eastern Sierra and Basin and Range: 1) Authigenic clay minerals in the Mio-Pliocene Verdi Basin (VB), 2) Fluvial and lacustrine carbonates from the Plio-Pleistocene Coso Basin (CB), and 3) Miocene to Holocene pedogenic, fluvial and lacustrine carbonates of Fish Lake Valley (FLV). Whereas both the VB (near present-day Reno) and CB (southern Owens Valley) receive input of water directly from the Sierra crest, FLV is a region of proposed reconvergence of moisture in the Basin and Range. The oxygen isotope records in both CB and FLV increase during the Neogene by approximately 2 ‰, while the hydrogen isotope record of the VB decreases by <10 ‰. These results are consistent with a modestly-elevated Paleogene Sierra of 2 km over which air masses traversed and underwent orographic rainout and Rayleigh distillation. A Neogene pulse of uplift in the southern Sierra could have driven modern flow

  13. Interagency technical consultation on improving mortality reporting in Sierra Leone: meeting report

    PubMed Central

    Asfaw, Yonas; Boateng, Isaac; Calderon, Mauricio; Caleo, Grazia; Conteh, Allan; Conteh, Salifu; Dafae, Foday; Dey, Achintya; Duffy, Nadia; Davies, Daffney; Fatoma, Patrick; Fleming, John; Gogra, Boima; Gorina, Yelena; Grigoryan, Anna; Hersey, Sara; Hoare, Sam; Jabbi, Sonnia-Magba Bu-Buakei; Jambai, Amara; Jasperse, Joseph; Kaiser, Reinhard; Kallon, Gandi; Kamara, Ansumana; Kamara, Fatmata Zara; Kamara, Isata Pamela; Kamara, Wogba; Kandeh, Joseph; Kanu, Mustapha; Kargbo, Mabinty; Kargbo, Samuel; Konie, Richard; Kuyembeh, Simeon; Lansana, Patrick; Mclysaght, Fiona; McCann, Sheena; Nallo, Alhaji Samuka; Ngai, Stephanie; Nichols, Erin; Njuguna, Charles; O-Tipo, Shikanga; Parker, Sulaiman; Rafique, Nuzhat; Redd, John; Samba, Thomas; Souza, Kerry; Tran, Alex; Younge, Chief Mathew Gibao

    2017-01-01

    By the end of the Ebola epidemic, death reporting in Sierra Leone (SL) became more acceptable amongst local populations, with nearly all deaths being reported to the Ebola hot line alert centers. To continue the positive momentum generated by the epidemic, the Sierra Leone Ministry of Health and Sanitation (MoHS) and the US Centers for Disease Control and Prevention (CDC) organized and conducted the two-day Inter-agency Consultations on Improving Mortality Reporting in Sierra Leone (Consultations). In conjunction with the Consultations, participants were also offered a one-day, in-person training on the major components, characteristics, and uses of a national Civil Registration and Vital Statistics (CRVS) system. To understand processes used by governmental and non-governmental organizations in collection of death data before and during the Ebola epidemic, and to develop recommendations on improving death reporting and CRVS in Sierra Leone. The Inter-agency Consultations were conducted in person over two days in October, 2015. Real-time notes were kept by CDC staff for later abstraction and summarizing. Presenters agreed to share their materials (usually PowerPoint presentations) and approved the summaries. Challenges to implementation and suggestions for improving death reporting were drawn from the presentations and from anonymous suggestions collected at the end of each of three days of the Consultations. The Consultations attracted more than 80 participants from 28 Sierra Leone governmental, business, and other non-governmental organizations. Over the course of 18 presentations, participants presented and discussed the ways deaths were reported before and during the Ebola epidemic and ways in which the CRVS in Sierra Leone might be improved. The presentations made clear the need to improve death reporting in order to improve the health status of Sierra Leone. Many presenters and participants discussed the challenges to improvements, including lack of

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

    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

  15. Effect of a low-density polyethylene film containing butylated hydroxytoluene on lipid oxidation and protein quality of Sierra fish (Scomberomorus sierra) muscle during frozen storage.

    PubMed

    Torres-Arreola, Wilfrido; Soto-Valdez, Herlinda; Peralta, Elizabeth; Cardenas-López, José Luis; Ezquerra-Brauer, Josafat Marina

    2007-07-25

    Fresh sierra fish (Scomberomorus sierra) fillets were packed in low-density polyethylene films with butylated hydroxytoluene (BHT-LDPE) added. Fillets packed in LDPE with no BHT were used as controls (LDPE). The packed fillets were stored at -25 degrees C for 120 days in which the film released 66.5% of the antioxidant. The influence of the antioxidant on lipid and protein quality, lipid oxidation, muscle structure changes, and shear-force resistance was recorded. As compared to LDPE films, fillets packed in BHT-LDPE films showed lower lipid oxidation, thiobarbituric acid values (4.20 +/- 0.52 vs 11.95 +/- 1.06 mg malonaldehyde/kg), peroxide values (7.20 +/- 1.38 vs 15.15 +/- 1.48 meq/kg), and free fatty acids (7.98 +/- 0.43 vs 11.83 +/- 1.26% of oleic acid). Fillets packed in BHT-LDPE films showed less tissue damage and lost less firmness than fillets packed in LDPE. A significant relationship between lipid oxidation and texture was detected (R2 adjusted, 0.70-0.73). BHT-LDPE films may be used not only to prevent lipid oxidation but also to minimize protein damage to prolong the shelf life of sierra fish.

  16. Comparison of surgical care deficiencies between US civil war hospitals and present-day hospitals in Sierra Leone.

    PubMed

    Crompton, Joseph; Kingham, T Peter; Kamara, T B; Brennan, Murray F; Kushner, Adam L

    2010-08-01

    Surgery is rapidly becoming a part of public health initiatives in developing countries. In collaboration with the Sierra Leone Ministry of Health and Sanitation, a team of local surgeons and surgeons from the organization Surgeons OverSeas (SOS) used the WHO Tool for Situational Analysis to Assess Emergency Surgical Care to quantify surgical capacity in Sierra Leone. These data were then compared to data collected from the Medical and Surgical History of the Civil War, a work documenting surgical care and hospitals during the US Civil War. There are 0.2 government hospital surgeons/100,000 people in Sierra Leone compared to 300 surgeons/100,000 soldiers in the Union Army. In Sierra Leone it is rare to have running water, fuel, anesthesia, and reliable X-rays. In comparison, US Civil War hospitals had reliable running water, fuel, and anesthesia. It is rare to manage open fractures, limb dislocations, amputations, and conditions requiring chest tubes in Sierra Leone, while these procedures were commonly employed in US Civil War hospitals. Government hospitals in present day Sierra Leone lack the infrastructure, personnel, supplies, and equipment to adequately provide emergency and essential surgical care. In a comparison of present day Sierra Leonean and US Civil War hospitals, the US Civil War facilities are equivalent and in many ways superior. It is hoped that such a comparison will aid advocacy efforts so that greater resources are devoted to improving emergency and essential surgical care in low- and middle-income countries.

  17. Paleozoic and Mesozoic deformations in the central Sierra Nevada, California

    Nokleberg, Warren J.; Kistler, Ronald Wayne

    1980-01-01

    Analysis of structural and stratigraphic data indicates that several periods of regional deformation, consisting of combined folding, faulting, cataclasis, and regional metamorphism, occurred throughout the central Sierra Nevada during Paleozoic and Mesozoic time. The oldest regional deformation occurred alono northward trends during the Devonian and Mississippian periods in most roof pendants containing lower Paleozoic metasedimentary rocks at the center and along the crest of the range. This deformation is expressed in some roof pendants by an angular unconformity separating older thrice-deformed from younger twice-deformed Paleozoic metasedimentary rocks. The first Mesozoic deformation, which consisted of uplift and erosion and was accompanied by the onset of Andean-type volcanism during the Permian and Triassic, is expressed by an angular unconformity in several roof pendants from the Saddlebag Lake to the Mount Morrison areas. This unconformity is defined by Permian and Triassic andesitic to rhyolitic metavolcanic rocks unconformably overlying more intensely deformed Pennsylvanian, Permian(?), and older metasedimentary rocks. A later regional deformation occurred during the Triassic along N. 20?_30? W. trends in Permian and Triassic metavolcanic rocks of the Saddlebag Lake and Mount Dana roof pendants, in upper Paleozoic rocks of the Pine Creek roof pendant, and in the Calaveras Formation of the western metamorphic belt; the roof pendants are crosscut by Upper Triassic granitic rocks of the Lee Vining intrusive epoch. A still later period of Early and Middle Jurassic regional deformation occurred along N. 30?-60? E. trends in upper Paleozoic rocks of the Calaveras Formation of the western metamorphic belt. A further period of deformation was the Late Jurassic Nevadan orogeny, which occurred along N. 20?_40? W. trends in Upper Jurassic rocks of the western metamorphic belt that are crosscut by Upper Jurassic granitic rocks of the Yosemite intrusive epoch

  18. Holocene glaciation of the central Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Bowerman, Nicole D.; Clark, Douglas H.

    2011-05-01

    Sediment cores from two bedrock-dammed lakes in North Fork Big Pine Creek, Sierra Nevada, California, preserve the most detailed and complete record of Holocene glaciation yet recovered in the region. The lakes are fed by outwash from the Palisade Glacier, the largest (˜1.3 km 2) and presumably longest-lived glacier in the range, and capture essentially all of the rock flour it produces. Distinct late-Holocene (Matthes) and late-Pleistocene (Recess Peak) moraines lie between the modern glacier and the lakes. The lakes have therefore received continuous sedimentation from the basin since the retreat of the Tioga glacier (Last Glacial Maximum) and capture rock flour related to all post-LGM advances. A total of eight long cores (up to 5.5 m sediment depth) and one short surface sediment short core preserve a coherent record of fluctuating rock flour flux to the lakes through the Holocene. Age constraints on rock flour spikes in First and Second lakes based on 31 14C-dated macrofossils indicate Holocene glaciation began ˜3200 cal yr B P, followed by a possible glacier maximum at ˜2800 cal yr B P and four distinct glacier maxima at ˜2200, ˜1600, ˜700 and ˜250-170 cal yr. B.P., the most recent maximum being the largest. Reconstruction of the equilibrium-line altitudes (ELA) associated with each distinct advance recorded in the moraines (Recess Peak, Matthes, and modern) indicates ELA depressions (relative to modern) of ˜250 m and 90 m for Recess Peak and Matthes advances, respectively. These differences represent decreases in summer temperatures of 1.7-2.8 °C (Recess Peak) and 0.2-2° (Matthes), and increases in winter precipitation of 22-34 cm snow water equivalent (s.w.e.) (Recess Peak) and 3-26 cm s.w.e. (Matthes) compared to modern conditions. Although small, these changes are significant and similar to those noted in the Cascade Range to the north, and represent a significant departure from historical climate trends in the region.

  19. The effects of epilepsy on child education in Sierra Leone.

    PubMed

    Ali, Desta B; Tomek, Michal; Lisk, Durodami R

    2014-08-01

    Epilepsy is associated with a significant burden of false beliefs and social stigma in the setting of Sub-Saharan Africa. To assess the impacts of epilepsy on child education in Sierra Leone (SL), we carried out a cross-sectional descriptive study examining its effects on school attendance, participation in physical activities, and social acceptance among classmates. We also assessed the knowledge, beliefs, and attitudes regarding epilepsy of both the children's caregivers and teachers. The data were collected at various epilepsy clinics and schools in Freetown, SL. A total of 50 patients were interviewed and questionnaires administered to their caregivers and teachers, making a total of 150 respondents. Fifty-one percent of the children were absent from school for >5 days per month. Ninety percent did not participate in games and sports, with the commonest reason being fear of occurrence of seizures. Thirty-six percent claimed having experienced negative attitude from their classmates. Regarding the caregivers, 48% believed that epilepsy was a medical illness, while 34% considered it a demonic manifestation. Forty-eight percent were apprehensive about sending their children to school, with 83% of these caregivers stating fear of seizures and potential injuries. Only 8% of the caregivers did not prevent their children from taking part in any physical activity at school. Regarding the teachers, 16% believed that epilepsy was a demonic manifestation, and 10% thought that it was contagious. Fourteen percent did not think that children with epilepsy should go to school, and 80% would prevent children with epilepsy from participating in games and sports. When faced with a child having a seizure, 48% would hold the child down, 12% would place a hard object in the child's mouth, and 12% would avoid any physical contact. In total, 20% of the children ceased attending school permanently; daily occurrence of seizures (p<0.05), negative attitude of classmates (p<0.001), and

  20. Influence of anuran prey on the condition and distribution of Rana muscosa in the Sierra Nevada

    K.L. Pope; K.R. Matthews

    2002-01-01

    Mountain yellow-legged frogs (Rana muscosa) at high elevations of the Sierra Nevada must obtain enough food during summer to survive 7–9 winter months when their aquatic habitats are frozen and food is presumably unavailable. Adults of R. muscosa prey on a variety of organisms, including aquatic and terrestrial invertebrates and...

  1. DC-8 Airborne Laboratory in flight over snow-capped Sierra Nevada mountain range

    1998-02-25

    NASA's DC-8 Airborne Laboratory during a flight over the snow-covered Sierra Nevada Mountains. Over the past several years the DC-8 has conducted research missions in such diverse places as the Pacific in spring and Sweden in winter.

  2. Response of Sierra Nevada vegetation and fire regimes to past climate changes

    R. Scott Anderson

    2004-01-01

    The study of changing vegetation patterns within forested communities of the Sierra Nevada has had a long history, initiated by the great naturalist John Muir. More recently, paleoecologists, who study ecosystems of the past, have analyzed fossil plant remains recovered from lake and meadow sediments to understand the regional biogeography and disturbance history of...

  3. Trajectories of Internalizing Problems in War-Affected Sierra Leonean Youth: Examining Conflict and Postconflict Factors

    ERIC Educational Resources Information Center

    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…

  4. Achieving a nexus of science, management, and policy in the Sierra Nevada

    Peter A. Stine; Dennis D. Murphy

    2004-01-01

    The policies and strategies that guide the use and management of lands in the Sierra Nevada ecoregion depend on objective scientific information. In recent years, the region has attracted increasing attention from visitors, developers, environmentalists, businesses, scientists, and politicians as well as local residents, resource managers, and research groups. And the...

  5. Flying High With Civil Air Patrol: The Sierra Blanca Civil Air Patrol Squadron.

    ERIC Educational Resources Information Center

    Carnicom, Gene E.

    The Sierra Blanca Civil Air Patrol (CAP) Cadet Squadron from Mescalero, New Mexico, is a program funded by the tribe and the state of New Mexico for Mescalero Apache youth. The national CAP Cadet Program promotes moral leadership, aerospace education, leadership, and physical fitness; Mescalero cadets have learned self-confidence and leadership…

  6. Response of Brown Creepers to elevation and forest edges in the southern Sierra Nevada, California

    Kathryn Purcell; Craig Thompson; Douglas Drynan

    2012-01-01

    We studied the responses of the Brown Creeper (Certhia americana) to forest edges in the southern Sierra Nevada, California. We censused birds and monitored nests in four forest types over an elevational gradient. We identified habitat patches homogeneous in terms of forest type, seral stage, and canopy cover and rated edges between adjoining...

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

    PubMed

    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.

  8. Simulating fire and forest dynamics for a coordinated landscape fuel treatment project in the Sierra Nevada

    Brandon M. Collins; Scott L. Stephens; Gary B. Roller; John Battles

    2011-01-01

    We evaluate an actual landscape fuel treatment project that was designed by local U. S. Forest Service managers in the northern Sierra Nevada. We model the effects of this project at reducing landscape-level fire behavior at multiple time steps, up to nearly 30 yr beyond treatment implementation. Additionally, we modeled planned treatments under multiple diameter-...

  9. What Is Shakespeare Doing in My Hut?: A-Level Literature and the Sierra Leonean Student.

    ERIC Educational Resources Information Center

    Wright, Handel K.

    A study brought together literature appreciation, schema theory, and cross-cultural studies to explore the relationship between the backgrounds of students in one sixth-form literature class in Sierra Leone and the contexts of the plays described in the drama section of the "A" level literature syllabus of the West African Examinations…

  10. Developing and managing sustainable forest ecosystems for spotted owls in the Sierra Nevada

    J. Verner; K.S. McKelvey

    1994-01-01

    Studies of the California spotted owl have revealed significant selection for habitats with large, old trees; relatively high basal areas of snags; and relatively high biomass in large, downed logs. Based on planning documents for national forests in the Sierra Nevada, we projected declining amounts of older-forest attributes. Region 5 has adopted measures to retain...

  11. Biogeochemistry of a soil catena in the eastern Sierra Nevada Range, NV

    As a field/lab project, students in the Soil Biogeochemistry class of the University of Nevada, Reno described and characterized five pedons at Little Valley, NV, at the eastern edge of the Sierra Nevada. Developed largely from granite, the catena encompassed five pedons, which from high to low elev...

  12. Concentration-discharge relationships in headwater streams of the Sierra Nevada, California

    Carolyn T. Hunsaker; Dale W. Johnson

    2017-01-01

    We examined streamwater concentration-discharge relationships for eight small, forest watersheds ranging in elevation from 1,485 to 2,465 m in the southern Sierra Nevada. These headwater streams revealed nearly chemostatic behavior by current definitions for K+, Ca...

  13. Using epiphytic macrolichen communities for biomonitoring ammonia in forests of the greater Sierra Nevada, California

    Sarah Jovan; Bruce Mccune

    2006-01-01

    Chronic, excessive nitrogen deposition is potentially an important ecological threat to forests of the greater Sierra Nevada in California. We developed a model for ammonia bioindication, a major nitrogen pollutant in the region, using epiphytic macrolichens. We used non-metric multidimensional scaling to extract gradients in lichen community composition from surveys...

  14. Roadless area-intensive management tradeoffs on the Sierra National Forest, California

    Robert J. Hrubes; Kent P. Connaughton; Robert W. Sassaman

    1979-01-01

    This hypothesis was tested by a linear programing model: Roadless areas on the Sierra National Forest precluded from planned future development would be candidates for wilderness designation, and the associated loss in present and future timber harvests could be offset by investing in more intensive management. The results of this simulation test suggest that levels of...

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

    ERIC Educational Resources Information Center

    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…

  16. Estimating past diameters of mixed conifer species in the central Sierra Nevada

    K. Leroy Dolph

    1981-01-01

    Tree diameter outside bark at an earlier period of growth can be estimated from the linear relationship of present inside bark and outside bark diameters at breast height. This note presents equations for estimating inside bark diameters, outside bark diameters, and past outside bark diameters for each of the mixed-conifer species in the central Sierra Nevada.

  17. A density management diagram for even-aged Sierra Nevada mixed-conifer stands

    James N. Long; John D. Shaw

    2012-01-01

    We have developed a density management diagram (DMD) for even-aged mixed-conifer stands in the Sierra Nevada Mountains using forest inventory and analysis (FIA) data. Analysis plots were drawn from FIA plots in California, southern Oregon, and western Nevada which included those conifer species associated with the mixed-conifer forest type. A total of 204 plots met the...

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

    EPA Science Inventory

    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...

  19. DISTRIBUTIONS OF AIRBORNE AGRICULTURAL CONTAMINANTS RELATIVE TO AMPHIBIAN POPULATIONS IN THE SOUTHERN SIERRA NEVADA, CA

    EPA Science Inventory

    The Sierra Nevada mountain range lies adjacent to one of the heaviest pesticide use areas in the USA, the Central Valley of California. Because of this proximity, concern has arisen that agricultural pesticides, in addition to other contaminants, are adversely affecting the natur...

  20. NASA Acting Deputy Chief Technologist Vicki Crisp Discusses Sierra Nevada Corporation's Dream Chaser with Lee Archambault

    2017-08-30

    NASA Acting Deputy Chief Technologist Vicki Crisp discusses Sierra Nevada Corporation’s Dream Chaser captive carry flight and future tests with former Astronaut Lee "Bru" Archambault, who is now a test pilot for the American company. The Dream Chaser completed a successful captive carry flight at NASA’s Armstrong Flight Research Center at Edwards, California, on Aug. 30, 2017.

  1. Linking Research, Extension and Farmers: The Case of Mangrove Swamp Rice Cultivation in Sierra Leone.

    ERIC Educational Resources Information Center

    Zinnah, Moses Moroe

    1994-01-01

    Interviews with 124 rice farmers in Sierra Leone revealed that farmers and extension staff have minimal participation and input in testing of new cultivation technologies. The top-down research approach has limited contact among researchers, extension staff, and farmers and affected the utility and application of research. (SK)

  2. Nutrient fluxes in forests of the eastern Sierra Nevada: comparisons with humid forest systems

    Dale W. Johnson; Richard B. Susfalk; Randy A. Dahlgreen; Virginia Boucher; Andrzej Bytnerowicz

    1998-01-01

    Preliminary results of studies on nutrient fluxes in forests of the eastern Sierra Nevada were compared to those from more humid and polluted ecosystems. Snowmelt, soil solution, soil, and streamwater were collected from Jeffrey and lodgepole pine (Pinus jeffreyii [Grev. and Balf.] and Pinus contorta Dougl.) stands in Little Valley...

  3. A Grammar of Sierra Popoluca (Soteapanec, a Mixe-Zoquean Language)

    ERIC Educational Resources Information Center

    de Jong Boudreault, Lynda J.

    2009-01-01

    This dissertation is a comprehensive description of the grammar of Sierra Popoluca (SP, aka Soteapanec), a Mixe-Zoquean language spoken by approximately 28,000 people in Veracruz, Mexico. This grammar begins with an introduction to the language, its language family, a typological overview of the language, a brief history of my fieldwork, and the…

  4. Snowmelt runoff and water yield along elevation and temperature gradients in California's southern Sierra Nevada

    Carolyn T. Hunsaker; Thomas W. Whitaker; Roger C. Bales

    2012-01-01

    Differences in hydrologic response across the rain-snow transition in the southern Sierra Nevada were studied in eight headwater catchments – the Kings River Experimental Watersheds – using continuous precipitation, snowpack, and streamflow measurements. The annual runoff ratio (discharge divided by precipitation) increased about 0.1 per 300 m of mean catchment...

  5. Estimating trend in occupancy for the Southern Sierra fisher Martes pennanti population

    William J. Zielinski; James A. Baldwin; Richard L. Truex; Jody M. Tucker; Patricia A. Flebbe

    2013-01-01

    Carnivores are important elements of biodiversity, not only because of their role in transferring energy and nutrients, but also because they influence the structure of the communities where they occur. The fisher Martes pennanti is amammalian carnivore that is associated with late-successional mixed forests in the Sierra Nevada in California, and...

  6. Lessons learned from prescribed fire in ponderosa pine forests of the southern Sierra Nevada

    Karen E. Bagne; Kathryn L. Purcell

    2009-01-01

    Prescribed fire is a commonly used management tool in fire-suppressed ponderosa pine (Pinus ponderosa) forests, but effects of these fires on birds are largely unstudied. We investigated both direct and indirect impacts on breeding birds in ponderosa pine forests of the southern Sierra Nevada where fires were applied in the spring. Following...

  7. Petrography of the Paleogene Volcanic Rocks of the Sierra Maestra, Southeastern Cuba

    NASA Astrophysics Data System (ADS)

    Bemis, V. L.

    2006-12-01

    This study is a petrographic analysis of over 200 specimens of the Paleogene volcanic rocks of the Sierra Maestra (Southerneastern Cuba), a key structure in the framework of the northern Caribbean plate boundary evolution. The purpose of this study is to understand the eruptive processes and the depositional environments. The volcanic sequence in the lower part of the Sierra Maestra begins with highly porphyritic pillow lavas, topped by massive tuffs and autoclastic flows. The presence of broken phenocrystals, palagonitic glass and hyaloclastites in this section of the sequence suggests that the prevalent mode of eruption was explosive. The absence of welding in the tuffs suggests that the rocks were emplaced in a deep submarine environment. Coherent flows, much less common than the massive tuffs, show evidence of autoclastic fracturing, also indicating low temperature-submarine environments. These observations support the hypothesis that the Sierra Maestra sequence may be neither part of the Great Antilles Arc of the Mesozoic nor any other fully developed volcanic arc, rather a 250 km long, submarine eruptive system of dikes, flows and sills, most likely a back-arc structure. The volcanic rocks of the upper sequence are all very fine grained, reworked volcaniclastic materials, often with the structures of distal turbidities, in mode and texture similar to those drilled on the Cayman Rise. This study suggests that the Sierra Maestra most likely records volcanism of diverse sources: a local older submarine source, and one or more distal younger sources, identifiable with the pan-Caribbean volcanic events of the Tertiary.

  8. Climate change and fire regimes in the Sierra de Manantlan, Mexico

    Brooke A. Cassell; Ernesto Alvarado; Emily Heyerdahl; Diego Perez-Salicrup; Enrique Jardel-Pelaez

    2010-01-01

    Fire has been attributed as one of the most influential factors in vegetation community and succession in the Sierra de Manantlán Biosphere Reserve in Jalisco and Colima, México. A mosaic of low, mixed and high severity fire regimes characterizes the landscape with ecosystems ranging from mesophyllous mountain forest to higher elevation pine and oak forest. Research...

  9. Constraints on mechanized treatment significantly limit mechanical fuels reduction extent in the Sierra Nevada

    Malcolm P. North; April Brough; Jonathan W. Long; Brandon M. Collins; Phil Bowden; Don Yasuda; Jay Miller; Neil Suighara

    2015-01-01

    With air quality, liability, and safety concerns, prescribed burning and managed wildfire are often considered impractical treatments for extensive fuels reduction in western US forests. For California's Sierra Nevada forests, we evaluated the alternative and analyzed the amount and distribution of constraints on mechanical fuels treatments on USDA Forest Service...

  10. Ecology, biodiversity, management, and restoration of aspen in the Sierra Nevada

    Wayne D. Shepperd; Paul C. Rogers; David Burton; Dale L. Bartos

    2006-01-01

    This report was commissioned by the USDA Forest Service Lake Tahoe Basin Management Unit to synthesize existing information on the ecology and management of aspen (Populus tremuloides) in the Sierra Nevada of California and surrounding environs. It summarizes available information on aspen throughout North America from published literature, internal...

  11. Riparian and upland vegetation on the Kings River Experimental Watershed, Sierra Nevada, California

    Christopher R. Dolanc; Carolyn T. Hunsaker

    2007-01-01

    The Kings River Experimental Watershed (KREW) is a watershed-level study on headwater streams in the Sierra Nevada, California. Eight perennial streams, from 1500 m (4920 ft) to 2490 m (8170 ft) elevation, have been instrumented and collecting data since 2002. Component research areas of the study include stream flow, water chemistry, sediment, soil chemistry, stream...

  12. Oak management by county jurisdictions in the central Sierra Nevada, California

    Richard R. Harris; Susan D. Kocher

    2002-01-01

    We evaluated county planning policies and procedures to determine what protection is provided to oak woodlands during the land development process. We selected three Sierra Nevada counties to do a pilot assessment: El Dorado, Placer and Madera. The assessment methodology included three components: 1) analysis of county plans, policies, guidelines, and ordinances to...

  13. Habitat modeling and movements of the Yosemite toad (Anaxyrus (=Bufo) canorus) in the Sierra Nevada, California

    C.T. Liang

    2010-01-01

    The Yosemite toad (Anaxyrus (=Bufo) canorus) is a high-elevation species endemic to the Sierra Nevada mountain range in California and is part of the world-wide amphibian declines phenomenon. The toad is thought to have disappeared from over 50% of its historic range even in seemingly undisturbed areas, and...

  14. Ozone distribution in remote ecologically vulnerable terrain of the southern Sierra Nevada, CA

    Jeanne Panek; David Saah; Annie Esperanza; Andrzej Bytnerowicz; Witold Fraczek; Ricardo Cisneros

    2013-01-01

    Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more...

  15. Factors influencing the scarification and germination of three montane Sierra Nevada shrubs

    J. Boone Kaufmann; R. E. Martin

    1991-01-01

    Following fires in the forested ecosystems of the northern Sierra Nevada, California, early successional communities are often dominated by shrubs that arise from seeds that have remained viable in soil seedbanks for long periods. The germination response of seeds of three seral montane shrub species was investigated following exposure to differing types of heat (wet...

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

    EPA Science Inventory

    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...

  17. 78 FR 24515 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ... Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for... Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra Nevada Yellow-Legged Frog, the... that the designation of critical habitat is not prudent. (2) Specific information on: (a) The amount...

  18. Sierra Nevada grasslands: interactions between livestock grazing and ecosystem structure and function

    Barbara H. Allen-Diaz

    2004-01-01

    Livestock grazing plays an integral role in the grass-dominated ecosystems of the Sierra Nevada. Grazing has been asserted to influence such key ecological characteristics as water quality, net primary productivity, nutrient cycling, plant and animal diversity, wildlife habitat availability, and oak regeneration (Belsky and others 1999, Kauffmann and Krueger 1984)....

  19. West nile virus anti-body surveillance in three Sierra Nevada raptors of conservation concern

    J.M. Hull; J.J. Keane; L.A. Tell; H.B. Ernest

    2010-01-01

    West Nile virus (WNV) infection has caused high levels of mortality in North American hawks and owls. To investigate the extent of infection among raptors of conservation concern in the Sierra Nevada, we tested 62 Northern Goshawks (Accipiter gentilis), 209 Spotted Owls (Strix occidentalis), and 22 Great Gray Owls (...

  20. Aspen in the Sierra Nevada: Regional conservation of a continental species

    Paul C. Rogers; Wayne D. Shepperd; Dale L. Bartos

    2007-01-01

    Quaking aspen (Populus tremuloides Michx.) a common species in North America, is a minor species in the Sierra Nevada of California. However, the limited coverage of aspen in this area appears to carry a disproportionate biodiversity load: numerous species are dependent on the unique components of aspen forests habitat. Land managers in the region...

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

    ERIC Educational Resources Information Center

    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…

  2. Resting structures and resting habitat of fishers in the southern Sierra Nevada, California

    Kathryn L. Purcell; Amie K. Mazzoni; Sylvia R. Mori; Brian B. Boroski

    2009-01-01

    The fisher (Martes pennanti) is a forest mustelid endemic to North America that has experienced range reductions in Pacific states that have led to their listing under the Endangered Species Act as warranted but precluded by higher priorities. The viability of the southern Sierra Nevada fisher population is of particular concern due to its reduced...

  3. Youth Reintegration Training and Education for Peace (YRTEP) Program: Sierra Leone, 2000-2001. Impact Evaluation.

    ERIC Educational Resources Information Center

    Fauth, Gloria; Daniels, Bonnie

    Management Systems International (MSI), with funding from United States Agency for International Development Office of Transition Initiatives (USAID/OTI) and in coordination with other partners, is implementing a program in Sierra Leone entitled "Youth Reintegration Training and Education for Peace" (YRTEP). The object is to provide…

  4. Thermal and hydrologic attributes of rock glaciers and periglacial talus landforms: Sierra Nevada, California, USA

    Constance I. Millar; Robert D. Westfall; Diane L. Delany

    2013-01-01

    To explore thermal regimes and hydrologic capacity of rock glaciers and related periglacial talus landforms, mini-thermochrons were deployed in and around potentially ice-embedded features of the Sierra Nevada. Results from pilot studies at 13 rock glaciers and 7 taluses indicate that outlet springs from these landforms generally do not desiccate but persist year...

  5. Conifer seedling survival under closed-canopy and manzanita patches in the Sierra Nevada

    A. Plamboeck; M. North; T. Dawson

    2008-01-01

    After a century of fire suppression, prescribed fire and mechanical thinning are widely used to restore mixed-conifer forests in California’s Sierra Nevada, yet after these treatments, trees sometimes fail to regenerate on many sites, for several possible reasons. Notably, competition between shrubs and tree seedlings for scarce water during prolonged summer dry...

  6. Characteristics of Adolescent Sierra Leonean Refugees in Public Schools in New York City

    ERIC Educational Resources Information Center

    Davies, Amy Z.

    2008-01-01

    The tendency to view immigrant students as a monolithic group has masked the needs of specific groups of students. This study gives visibility to Sierra Leonean refugee students and indicates to policy makers, administrators, and teachers provisions that would facilitate the students' integration into the school system in the United States. The…

  7. Carbon and nutrient contents in soils from the Kings River Experimental Watersheds, Sierra Nevada Mountains, California

    D.W. Johnson; C.T. Hunsaker; D.W. Glass; B.M. Rau; B.A. Roath

    2011-01-01

    Soil C and nutrient contents were estimated for eight watersheds in two sites (one high elevation, Bull, and one low elevation, Providence) in the Kings River Experimental Watersheds in the western Sierra Nevada Mountains of California. Eighty-seven quantitative pits were dug to measure soil bulk density and total rock content, while three replicate surface samples...

  8. Historical effects of logging on forests of the Cascade and Sierra Nevada ranges of California

    William F. Laudenslayer; Herman H. Darr

    1990-01-01

    Ponderosa pine, Jeffrey pine, mixed conifer, and white fir forests of the Cascade and Sierra Nevada Ranges of California have been important resources and were extensively altered by timber harvest between 1850 and 1950. Many historical logging operations were small in size and of short duration. Other operations encompassed thousands of acres and existed for...

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

    ERIC Educational Resources Information Center

    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…

  10. Wildfire impacts on California spotted owl nesting habitat in the Sierra Nevada

    Scott L. Stephens; Jay D. Miller; Brandon M. Collins; Malcolm P. North; John J. Keane; Susan L. Roberts

    2016-01-01

    California spotted owls (CSOs) (Strix occidentalis occidentalis) have received significant conservation attention beginning with the U.S. Forest Service interim management guidelines in 1992. The most commonly reported forest habitat feature for successful nesting habitat of CSO is canopy cover > 70%. Loss and degradation of Sierra Nevada CSO habitat, however,...

  11. Silviculture-ecology of forest-zone hardwoods in the Sierra Nevada

    Philip M. McDonald; John C. Tappeiner

    1996-01-01

    Although the principal hardwood species in the forest zone of the Sierra Nevada (California black oak, tanoak, Pacific madrone, and canyon live oak) are key components of many ecosystems, they have received comparatively little study. Currently they are underutilized and unmanaged. This paper brings together what is known on the silviculture-ecology of these species...

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

    ERIC Educational Resources Information Center

    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…

  13. Plant diversity and invasives in blue oak savannas of the southern Sierra Nevada

    Jon E. Keeley

    2002-01-01

    Blue oak savannas were found to be substantially more diverse at all scales from localized point diversity to the community scale, than higher elevation shrubland and coniferous forests in the southern Sierra Nevada. Also, alien plants were more diverse and represented a substantial fraction of the understory flora in these blue oak savannas, comprising three-fourths...

  14. Role of oaks in fisher habitat quality in the Sierra Nevada mountains at multiple spatial scales

    Craig M. Thompson; Kathryn Purcell; Rebecca Green; Richard. Sweitzer

    2015-01-01

    Fishers (Pekania pennanti) occur in ponderosa pine, mixed conifer, and mixed hardwood conifer habitats in the southern Sierra Nevada at elevations from approximately 1400 to 2300 m. They are a candidate species for listing under both the Federal and California Endangered Species Acts. Since 2007, the U.S. Department of Agriculture, Forest Service (...

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

    ERIC Educational Resources Information Center

    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…

  16. Fire weather and large fire potential in the northern Sierra Nevada

    Brandon M. Collins

    2014-01-01

    Fuels, weather, and topography all contribute to observed fire behavior. Of these, weather is not only the most dynamic factor, it is the most likely to be directly influenced by climate change. In this study 40 years of daily fire weather observations from five weather stations across the northern Sierra Nevada were analyzed to investigate potential changes or trends...

  17. Forty years of land use and land ownership change in central Sierra Nevada oak woodlands

    Matt Wacker; David Saah; Louise Fortmann

    2002-01-01

    The vast majority of California’s oak woodlands are privately owned, and, therefore, highly susceptible to changes in land use and ownership as well as land fragmentation. This is particularly true in the Central Sierra Nevada, where significant changes in land use have occurred during the past 40 years. Perhaps no location illustrates this trend better than the...

  18. Burn Severity and Its Impact on Soil Properties: 2016 Erskine Fire in the Southern Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Haake, S.; Guo, J.; Krugh, W. C.

    2017-12-01

    Wildfire frequency in the southern Sierra Nevada has increased over the past decades. The effects of wildfires on soils can increase the frequency of slope failure and debris flow events, which pose a greater risk to people, as human populations expand into foothill and mountainous communities of the Sierra Nevada. Alterations in the physical properties of burned soils are one such effect that can catalyze slope failure and debris flow events. Moreover, the degree of a soil's physical alteration resulting from wildfire is linked to fire intensity. The 2016 Erskine fire occurred in the southern Sierra Nevada, burning 48,019 acres, resulting in soils of unburned, low, moderate, and high burn severities. In this study, the physical properties of soils with varying degrees of burn severity are explored within the 2016 Erskine fire perimeter. The results constrain the effects of burn severity on soil's physical properties. Unburned, low, moderate, and high burn severity soil samples were collected within the Erskine fire perimeter. Alterations in soils' physical properties resulting from burn severity are explored using X-ray diffractometry analysis, liquid limit, plastic limit, and shear strength tests. Preliminary results from this study will be used to assess debris flow and slope failure hazard models within burned areas of the Kern River watershed in the southern Sierra Nevada.

  19. Stability and change in minerotrophic peatlands, Sierra Nevada of California and Nevada

    James W. Bartolome; Don C. Erman; Charles F. Schwara

    1990-01-01

    Minerotrophic peatlands or fens in California's Sierra Nevada are small wet meadows surrounded by mixed conifer forest. The dynamics of vegetation change at the meadow edge and the ages and development of fens were investigated, in the Sagehen Creek Basin near Truckee, California, through the use of radiocarbon dating of peat, pollen studies, examination of...

  20. Winter sowings produce 1-0 sugar pine planting stock in the Sierra Nevada

    James L. Jenkinson; Arthur H. McCain

    1993-01-01

    Seed source and sowing date effects on first-year seedling growth and Fusarium root and collar rot of sugar pine were analyzed in two consecutive nursery tests at the Pacific Southwest Research Station's Institute of Forest Genetics, near Placerville in the western Sierra Nevada. The experimental design in both tests consisted of four replications of a randomized...

  1. Black bear abundance, habitat use, and food habits in the Sierra San Luis, Sonora, Mexico

    Rodrigo Sierra Corona; Ivan A. Sayago Vazquez; M. del Carmen Silva Hurtado; Carlos A. Lopez Gonzalez

    2005-01-01

    We studied black bears to determine habitat use, food habits, and abundance between April 2002 and November 2003 in the Sierra San Luis, Sonora. We utilized transects to determine spoor presence, camera traps for abundance, and scat analysis. During 2002, bears fed principally on plant material, and for 2003 on animal matter, namely livestock. Habitat use differed...

  2. Population dynamics of the California spotted owl in the Sierra Nevada, California

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

    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,...

  3. Understanding Sierra Leonean and Liberian Teachers' Views on Discussing Past Wars in Their Classrooms

    ERIC Educational Resources Information Center

    Shepler, Susan; Williams, James H.

    2017-01-01

    Various curricular and textbook initiatives exist to aid in the national processes of coming to terms with past violence, often serving the political goals of the victors, sometimes supported by international transitional justice institutions. Sierra Leone and Liberia each experienced a devastating civil war during the 1990s and into the 2000s,…

  4. Thermal regimes and snowpack relations of periglacial talus slopes, Sierra Nevada, California, USA.

    Constance I Millar; Robert D. Westfall; Diane L. Delany

    2014-01-01

    Thermal regimes of eight periglacial talus slopes, at contrasting elevations, aspects, and substrates, in the Sierra Nevada, California, had complex microclimatic patterns partially decoupled from external conditions. Over three years, warm seasons showed mean talus matrix temperatures and daily variances lower than surfaces and cooler than free-air; talus surface and...

  5. Response of Vegetation Greenness to Climate Change in Meadows of the Sierra Nevada Mountains

    NASA Astrophysics Data System (ADS)

    von Kaenel, M.

    2016-12-01

    Wet meadows in the Sierra Nevada Mountain Range provide crucial ecological and hydrological services such as groundwater recharge and habitat to both wildlife and human communities, yet they are one of the most at-risk landscapes of the Sierra Nevada, with 40-60% of meadows impacted by degradation. These meadows also face the threat of global climate warming, which will bring earlier snowmelt and a greater proportion of precipitation as rain rather than snow in the Sierra Nevada, leading to shifts in the hydrology that governs meadow health and function. To assess the vulnerability of meadows to potential climate-driven degradation, this research relied on remote sensing to track maximum annual vegetation greenness as an indicator for vegetation health and consequentially meadow function in 2,512 Sierra Nevada meadows from 1989 to 2015, and correlated these fluctuations with changes in local climate. Peak snow water content, April 1st snowpack depth, and total annual precipitation are all positively correlated with maximum meadow greenness, with precipitation being the best predictor of greenness. The extent to which meadow greenness varies with changes in climate differs significantly across elevation, latitude, vegetation type, and dominant rock type. Based on data-derived sensitivities, I conclude that restoration should be prioritized in grassland meadows and meadows at high elevations, due to their high vulnerability to changes in climate and a high risk of global warming induced hydrological shifts.

  6. Evaluating avian-habitat relationships models in mixed-conifer forests of the Sierra Nevada

    Kathryn L. Purcell; Sallie J. Hejl; Terry A. Larson

    1992-01-01

    Using data from two studies in the southern and central Sierra Nevada, we compared the presence and abundance of bird species breeding in mixedconifer forests during 1978-79 and 1983-85 to predictions &om the California Wildlife Habitat Relationships (WHR) System. Twelve percent of the species observed in either study were not predicted by the WHR database to occur...

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

    ERIC Educational Resources Information Center

    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…

  8. The Violence of Peace and the Role of Education: Insights from Sierra Leone

    ERIC Educational Resources Information Center

    Novelli, Mario; Higgins, Sean

    2017-01-01

    Research on peacebuilding has mushroomed over the last decade and there is a growing interest in the role of education in supporting peacebuilding processes. This paper engages with these debates, UN peacebuilding activities and the location of education initiatives therein, through a case study of Sierra Leone. In the first part, we explore the…

  9. Fungi in the diets of northern flying squirrels and lodgepole chipmunks in the Sierra Nevada

    Marc D. Meyer; Malcolm P. North; Douglas A. Kelt

    2005-01-01

    The diets of a fungal specialist, northern flying squirrel (Glaucomys sabrinus (Shaw, 1801)), and a dietary generalist, lodgepole chipmunk (Neotamias speciosus (Merriam, 1890)), were examined in the old-growth, mixed-conifer forest at the Teakettle Experimental Forest in California's southern Sierra Nevada. Spores of fungi...

  10. Diversity of small mammals in the Sierra Nevada: Filtering by natural selection or by anthropogenic activities?

    Douglas A. Kelt; Rahel Sollmann; Angela M. White; Susan L. Roberts; Dirk H. Van Vuren

    2016-01-01

    Both historical and contemporary factors may influence the structure and composition of biotas. Small mammal faunas in the Sierra Nevada of California, United States, are strongly dominated by generalist species; however, whereas 1 recent study argues that this is a product of recent anthropogenic influences, another provides a deeper evolutionary explanation based on...

  11. Photo series for quantifying natural forest residues: southern Cascades, northern Sierra Nevada

    Kenneth S. Blonski; John L. Schramel

    1981-01-01

    A total of 56 photographs shows different levels of natural fuel loadings for selected size classes in seven forest types of the southern Cascade and northern Sierra-Nevada ranges. Data provided with each photo include size, weight, volumes, residue depths, and percent of ground coverage. Stand information includes sizes, weights, and volumes of the trees sampled for...

  12. Windthrown trees on the Kings River Ranger District, Sierra National Forest: meteorological aspects

    Michael A. Fosberg

    1986-01-01

    Blowdown in shelterwood, sanitation cuts, and other partial cuts on the Kings River Ranger District, Sierra National Forest, are due to Mono winds. Both winter storm and Mono winds were considered as causes of winter blowdown. All evidence, e.g., direction of tree-fall and occurrence of high wind events, point to Mono wind events as the cause of blowdown. Only 12...

  13. Current investigations of fungal ectomycorrhizal communities in the Sierra Nevada Forest

    Thomas D. Bruns; Annette M. Kretzer; Thomas R. Horton; Eric A-D. Stendell; Martin I. Bidartondo; Timothy M. Szaro

    2002-01-01

    Progress on two main studies on fungal ectomycorrhizal communities in the Sierra National Forest is discussed. One study examined the short-term effects of ground fire on the ectomycorrhizal community and the other examined the ectomycorrhizal associates of snow plant (Sarcodes sanguinea). In the ground-fire study we found that a large initial...

  14. A Miocene to Pleistocene climate and elevation record of the Sierra Nevada (California)

    PubMed Central

    Mulch, A.; Sarna-Wojcicki, A. M.; Perkins, M. E.; Chamberlain, C. P.

    2008-01-01

    Orographic precipitation of Pacific-sourced moisture creates a rain shadow across the central part of the Sierra Nevada (California) that contrasts with the southern part of the range, where seasonal monsoonal precipitation sourced to the south obscures this rain shadow effect. Orographic rainout systematically lowers the hydrogen isotope composition of precipitation (δDppt) and therefore δDppt reflects a measure of the magnitude of the rain shadow. Hydrogen isotope compositions of volcanic glass (δDglass) hydrated at the earth's surface provide a unique opportunity to track the elevation and precipitation history of the Sierra Nevada and adjacent Basin and Range Province. Analysis of 67 well dated volcanic glass samples from widespread volcanic ash-fall deposits located from the Pacific coast to the Basin and Range Province demonstrates that between 0.6 and 12.1 Ma the hydrogen isotope compositions of meteoric water displayed a large (>40‰) decrease from the windward to the leeward side of the central Sierra Nevada, consistent with the existence of a rain shadow of modern magnitude over that time. Evidence for a Miocene-to-recent rain shadow of constant magnitude and systematic changes in the longitudinal climate and precipitation patterns strongly suggest that the modern first-order topographic elements of the Sierra Nevada characterized the landscape over at least the last 12 million years. PMID:18441101

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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…

  17. Nesting habitat of Warbling Vireos across an elevational gradient in the southern Sierra Nevada

    Kathryn Purcell

    2007-01-01

    Populations of Warbling Vireos (Vireo gilvus) are declining in California, apparently due to low reproductive success. From 1989—2002, I studied the nest-site selection and reproductive success ofWarbling Vireos across an elevational gradient in the southern Sierra Nevada. Warbling Vireos regularly nested in upland coniferous forests with...

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

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

    2015-01-01

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

  19. Forested Communities of the Upper Montane in the Central and Southern Sierra Nevada

    Donald A. Potter

    1998-01-01

    Upper montane forests in the central and southern Sierra Nevada of California were classified into 26 plant associations by using information collected from 0.1-acre circular plots. Within this region, the forested environment including the physiographic setting, geology, soils, and vegetation is described in detail. A simulation model is presented for this portion of...

  20. Thinning – a tool for restoration of California's Southern Sierra Nevada blue oak woodlands

    Richard B. Standiford; Ralph L. Phillips; Neil K. McDougald

    2015-01-01

    Fire frequency on a blue oak (Quercus douglasii) dominated rangeland in California's southern Sierra Nevada foothills was approximately every 10 years until 1965, followed by a 30 year period of fire exclusion. This resulted in a dense tree overstory with small diameters, high crown cover, poor acorn and forage production, and limited...

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

    EPA Science Inventory

    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...

  2. Truffle abundance in riparian and upland mixed-conifer forest of California's southern Sierra Nevada

    Marc D. Meyer; Malcolm P. North

    2005-01-01

    We compared the abundance, diversity, and composition of truffles in riparian and upland areas within a mixed-conifer forest of the Sierra Nevada of California. We sampled for truffles in a single watershed over two seasons (spring and summer) and 4 years to determine whether truffles were more abundant and diverse in riparian than upland sites in old-growth, mixed-...

  3. Science synthesis to support socioecological resilience in the Sierra Nevada and southern Cascade Range

    Jonathan W. Long; Lenya Quinn-Davidson; Carl N. Skinner

    2014-01-01

    A team of scientists integrated recent research to inform forest managers, stakeholders, and interested parties concerned with promoting socioecological resilience in the Sierra Nevada, southern Cascade Range, and Modoc Plateau. Among the focal topics were forest and fire ecology; soils; aquatic ecosystems; forest carnivores including Pacific fisher, marten, and...

  4. Canopy microclimate response to pattern and density of thinning in a Sierra Nevada forest

    T. Rambo; M. North

    2009-01-01

    Restoring Sierra Nevada mixed-conifer forests after a century of fire suppression has become an important management priority as fuel reduction thinning has been mandated by the Healthy Forests Restoration Act. However, in mechanically thinned stands there is little information on the effects of different patterns and densities of live-tree retention on forest canopy...

  5. From Typology to Topography in Clarence King's "Mountaineering in the Sierra Nevada."

    ERIC Educational Resources Information Center

    Hoekzema, Loren

    The book "Mountaineering in the Sierra Nevada" by Clarence King, a late-ninteenth-century American geologist, writer, art critic, and romantic, is discussed in this paper. In the writing and revision of this book, King was attempting a metamorphosis of landscape description into popular reading as he moved from being a symbolic writer to…

  6. Culture and environment in the Sierra de Misantla, Veracruz, Mexico: the case of Oecopetalum mexicanum

    Maite Lascurain; Citlalli Lopez-Binnquist; Marla R. Emery

    2016-01-01

    We analyze the cultural and environmental dimensions of foraging the wild edible fruit cachichín (Oecopetalum mexicanum) in the Sierra de Misantla in central Veracruz, Mexico, including gathering practices, social organization, subsistence, commerce, and consumption. Gathering cachichín brings...

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Current and projected condition of mid-elevation Sierra Nevada forests

    Malcolm P. North; Mark W. Schwartz; Brandon M. Collins; John J. Keane

    2017-01-01

    Most of the California spotted owl’s (Strix occidentalis occidentalis) habitat is concentrated in mid-elevation forests of the Sierra Nevada (see chapter 9 for a discussion of southern California spotted owls and their habitat), which are made up primarily of ponderosa pine (Pinus ponderosa Lawson & C. Lawson), mixed-...

  9. Stratigraphy and Mesozoic–Cenozoic tectonic history of northern Sierra Los Ajos and adjacent areas, Sonora, Mexico

    Page, William R.; Gray, Floyd; Iriondo, Alexander; Miggins, Daniel P.; Blodgett, Robert B.; Maldonado, Florian; Miller, Robert J.

    2010-01-01

    Geologic mapping in the northern Sierra Los Ajos reveals new stratigraphic and structural data relevant to deciphering the Mesozoic–Cenozoic tectonic evolution of the range. The northern Sierra Los Ajos is cored by Proterozoic, Cambrian, Devonian, Mississippian, and Pennsylvanian strata, equivalent respectively to the Pinal Schist, Bolsa Quartzite and Abrigo Limestone, Martin Formation, Escabrosa Limestone, and Horquilla Limestone. The Proterozoic–Paleozoic sequence is mantled by Upper Cretaceous rocks partly equivalent to the Fort Crittenden and Salero Formations in Arizona, and the Cabullona Group in Sonora, Mexico.Absence of the Upper Jurassic–Lower Cretaceous Bisbee Group below the Upper Cretaceous rocks and above the Proterozoic–Paleozoic rocks indicates that the Sierra Los Ajos was part of the Cananea high, a topographic highland during the Late Jurassic and Early Cretaceous. Deposition of Upper Cretaceous rocks directly on Paleozoic and Proterozoic rocks indicates that the Sierra Los Ajos area had subsided as part of the Laramide Cabullona basin during Late Cretaceous time. Basal beds of the Upper Cretaceous sequence are clast-supported conglomerate composed locally of basement (Paleozoic) clasts. The conglomerate represents erosion of Paleozoic basement in the Sierra Los Ajos area coincident with development of the Cabullona basin.The present-day Sierra Los Ajos reaches elevations of greater than 2600 m, and was uplifted during Tertiary basin-and-range extension. Upper Cretaceous rocks are exposed at higher elevations in the northern Sierra Los Ajos and represent an uplifted part of the inverted Cabullona basin. Tertiary uplift of the Sierra Los Ajos was largely accommodated by vertical movement along the north-to-northwest-striking Sierra Los Ajos fault zone flanking the west side of the range. This fault zone structurally controls the configuration of the headwaters of the San Pedro River basin, an important bi-national water resource in the US

  10. Fumarole/plume and diffuse CO2 emission from Sierra Negra volcano, Galapagos archipelago

    NASA Astrophysics Data System (ADS)

    Padron, E.; Hernandez Perez, P. A.; Perez, N.; Theofilos, T.; Melian, G.; Barrancos, J.; Virgil, G.; Sumino, H.; Notsu, K.

    2009-12-01

    The active shield-volcano Sierra Negra is part of the Galapagos hotspot. Sierra Negra is the largest shield volcano of Isabela Island, hosting a 10 km diameter caldera. Ten historic eruptions have occurred and some involved a frequently visited east caldera rim fissure zone called Volcan Chico. The last volcanic event occurred in October 2005 and lasted for about a week, covering approximately twenty percent of the eastern caldera floor. Sierra Negra volcano has experienced some significant changes in the chemical composition of its volcanic gas discharges after the 2005 eruption. This volcanic event produced an important SO2 degassing that depleted the magmatic content of this gas. Not significant changes in the MORB and plume-type helium contribution were observed after the 2005 eruption, with a 65.5 % of MORB and 35.5 % of plume contribution. In 2006 a visible and diffuse gas emission study was performed at the summit of Sierra Negra volcano, Galapagos, to evaluate degassing rate from this volcanic system. Diffuse degassing at Sierra Negra was mainly confined in three different DDS: Volcan Chico, the southern inner margin of the caldera, and Mina Azufral. These areas showed also visible degassing, which indicates highly fractured areas where volcano-hydrothermal fluids migrate towards surface. A total fumarole/plume SO2 emission of 11 ± 2 td-1 was calculated by mini-DOAS ground-based measurements at Mina Azufral fumarolic area. Molar ratios of major volcanic gas components were also measured in-situ at Mina Azufral with a portable multisensor. The results showed H2S/SO2, CO2/SO2 and H2O/SO2 molar ratios of 0.41, 52.2 and 867.9, respectively. Multiplying the observed SO2 emission rate times the observed (gas)i/SO2 mass ratio we have estimated other volatiles emission rates. The results showed that H2O, CO2 and H2S emission rates from Sierra Negra are 562, 394, and 2.4 t d-1, respectively. The estimated total output of diffuse CO2 emission from the summit of

  11. Scaling up family planning in Sierra Leone: A prospective cost-benefit analysis.

    PubMed

    Keen, Sarah; Begum, Hashina; Friedman, Howard S; James, Chris D

    2017-12-01

    Family planning is commonly regarded as a highly cost-effective health intervention with wider social and economic benefits. Yet use of family planning services in Sierra Leone is currently low and 25.0% of married women have an unmet need for contraception. This study aims to estimate the costs and benefits of scaling up family planning in Sierra Leone. Using the OneHealth Tool, two scenarios of scaling up family planning coverage to currently married women in Sierra Leone over 2013-2035 were assessed and compared to a 'no-change' counterfactual. Our costing included direct costs of drugs, supplies and personnel time, programme costs and a share of health facility overhead costs. To monetise the benefits, we projected the cost savings of the government providing five essential social services - primary education, child immunisation, malaria prevention, maternal health services and improved drinking water - in the scale-up scenarios compared to the counterfactual. The total population, estimated at 6.1 million in 2013, is projected to reach 8.3 million by 2035 in the high scenario compared to a counterfactual of 9.6 million. We estimate that by 2035, there will be 1400 fewer maternal deaths and 700 fewer infant deaths in the high scenario compared to the counterfactual. Our modelling suggests that total costs of the family planning programme in Sierra Leone will increase from US$4.2 million in 2013 to US$10.6 million a year by 2035 in the high scenario. For every dollar spent on family planning, Sierra Leone is estimated to save US$2.10 in expenditure on the five selected social sector services over the period. There is a strong investment case for scaling up family planning services in Sierra Leone. The ambitious scale-up scenarios have historical precedent in other sub-Saharan African countries, but the extent to which they will be achieved depends on a commitment from both the government and donors to strengthening Sierra Leone's health system post-Ebola.

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

    PubMed Central

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

    2012-01-01

    Abstract We describe a new species of Bolitoglossa (Nanotriton) from the Sierra de Juárez and Sierra Mixe of Oaxaca, Mexico. Bolitoglossa chinanteca sp. 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. PMID:22577313

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

    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

  14. Macroeconomic costs of the unmet burden of surgical disease in Sierra Leone: a retrospective economic analysis

    PubMed Central

    Kamara, Thaim B; Lavy, Christopher B D; Leather, Andy J M; Bolkan, Håkon A

    2018-01-01

    Objectives The Lancet Commission on Global Surgery estimated that low/middle-income countries will lose an estimated cumulative loss of US$12.3 trillion from gross domestic product (GDP) due to the unmet burden of surgical disease. However, no country-specific data currently exist. We aimed to estimate the costs to the Sierra Leone economy from death and disability which may have been averted by surgical care. Design We used estimates of total, met and unmet need from two main sources—a cluster randomised, cross-sectional, countrywide survey and a retrospective, nationwide study on surgery in Sierra Leone. We calculated estimated disability-adjusted life years from morbidity and mortality for the estimated unmet burden and modelled the likely economic impact using three different methods—gross national income per capita, lifetime earnings foregone and value of a statistical life. Results In 2012, estimated, discounted lifetime losses to the Sierra Leone economy from the unmet burden of surgical disease was between US$1.1 and US$3.8 billion, depending on the economic method used. These lifetime losses equate to between 23% and 100% of the annual GDP for Sierra Leone. 80% of economic losses were due to mortality. The incremental losses averted by scale up of surgical provision to the Lancet Commission target of 80% were calculated to be between US$360 million and US$2.9 billion. Conclusion There is a large economic loss from the unmet need for surgical care in Sierra Leone. There is an immediate need for massive investment to counteract ongoing economic losses. PMID:29540407

  15. Observations on the extended tectonic history of the southern Sierra Nevada

    SciT

    Silver, L.T.

    1993-04-01

    The crust of the southern Sierra Nevada has been the site of repeated major tectonic dislocations in keeping with its Mesozoic-Cenzoic positions near active plate boundaries. The several Mesozoic magmatic arc which invaded it show evidence of pre- and inter-batholithic juxtapositions of different lithospheres as far back as the Jurassic. This has been noted in mapping strontium, neodymium and lead initial ratios and [delta][sup 18]O variations. The Cretaceous arc carries isotopic zonations consistent with a major lithospheric dislocation extending SE from the Melones-Bear Mountain fault systems through the southern Sierra Nevada into the Mojave desert (restoring the Garlock fault). Thismore » is a candidate site for the postulated late Jurassic Mojave-Sonora megashear. During Cretaceous arc evolution major plate changes have taken place at [approximately]104[+-]2 ma and [approximately]80--85 ma. A broad (100( )km) wedge of accreted deepwater sediments and oceanic crust was partly subducted eastward under the Cretaceous arc, producing the Rand, Pelona, Orocopia and Chocolate Mountain schists of southern California. The southern Sierra Nevada saw the northern part of this event. The underlying subduction zone was not disrupted; arc magmatism was quickly renewed in the northern part of the wedge (Rand Mountains). Eastern underthrusting was accompanied and followed by a succession of major westward-vergent low angle faults in the interval 80--60( ) ma with net displacements well in excess of 150 km, and shallow crustal surface rotations in the southern Sierra Nevada and adjacent regions. The southern Sierra Nevada is now clearly detached from its plutonic roots by several generations of low-angle faulting.« less

  16. Using machine learning to predict snow water equivalent in the Sierra Nevada USA and Afghanistan

    NASA Astrophysics Data System (ADS)

    Bair, N.; Rittger, K.; Dozier, J.

    2017-12-01

    In many mountain regions, snowmelt provides most of the runoff. Ranges such as the Sierra Nevada USA benefit from hundreds of manual and automated snow measurement stations as well as basin-wide snow water equavalent (SWE) estimates from new platforms like the Airborne Snow Observatory. Thus, we have been able to use the Sierra Nevada as a testbed to validate an approach called SWE reconstruction, where the snowpack is built-up in reverse using downscaled energy balance forcings. Our past work has shown that SWE reconstruction produces some of the most accurate basin-wide SWE estimates, comparable in accuracy to a snow pillow/course interpolation, but requires no in situ measurements, which is its main advantage. The disadvantages are that reconstruction cannot be used for a forecast and is only valid during the ablation period. To address these shortcomings, we have used machine learning trained on reconstructed SWE in the Sierra Nevada and Afghanistan, where there are no accessible snowpack measurements. Predictors are physiographic and remotely-sensed variables, including brightness temperatures from a new enhanced resolution passive microwave dataset. Two machine learning techniques—bagged regression trees and feed-forward neural networks—were used. Results show little bias on average and < 100 mm RMSE. For both areas, daily SWE climatology and fractional snow-covered area were the most important predictors. As expected, the passive microwave brigthness temperatures showed some predictive power in Afghanistan, with its almost nonexistent tree cover, but no predictive power in the Sierra Nevada, with its extensive canopy-covered snowpack. In the Sierra, we also explored how our machine learning approach performed outside of the training period, i.e. the ablation period.

  17. Quantifying surgical capacity in Sierra Leone: a guide for improving surgical care.

    PubMed

    Kingham, T Peter; Kamara, Thaim B; Cherian, Meena N; Gosselin, Richard A; Simkins, Meghan; Meissner, Chris; Foray-Rahall, Lynda; Daoh, Kisito S; Kabia, Soccoh A; Kushner, Adam L

    2009-02-01

    Lack of access to surgical care is a public health crisis in developing countries. There are few data that describe a nation's ability to provide surgical care. This study combines information quantifying the infrastructure, human resources, interventions (ie, procedures), emergency equipment and supplies for resuscitation, and surgical procedures offered at many government hospitals in Sierra Leone. Site visits were performed in 2008 at 10 of the 17 government civilian hospitals in Sierra Leone. The World Health Organization's Tool for Situational Analysis to Assess Emergency and Essential Surgical Care was used to assess surgical capacity. There was a paucity of electricity, running water, oxygen, and fuel at the government hospitals in Sierra Leone. There were only 10 Sierra Leonean surgeons practicing in the surveyed government hospitals. Many procedures performed at most of the hospitals were cesarean sections, hernia repairs, and appendectomies. There were few supplies at any of the hospitals, forcing patients to provide their own. There was a disparity between conditions at the government hospitals and those at the private and mission hospitals. There are severe shortages in all aspects of infrastructure, personnel, and supplies required for delivering surgical care in Sierra Leone. While it will be difficult to improve the infrastructure of government hospitals, training additional personnel to deliver safe surgical care is possible. The situational analysis tool is a valuable mechanism to quantify a nation's surgical capacity. It provides the background data that have been lacking in the discussion of surgery as a public health problem and will assist in gauging the effectiveness of interventions to improve surgical infrastructure and care.

  18. Macroeconomic costs of the unmet burden of surgical disease in Sierra Leone: a retrospective economic analysis.

    PubMed

    Grimes, Caris E; Quaife, Matthew; Kamara, Thaim B; Lavy, Christopher B D; Leather, Andy J M; Bolkan, Håkon A

    2018-03-14

    The Lancet Commission on Global Surgery estimated that low/middle-income countries will lose an estimated cumulative loss of US$12.3 trillion from gross domestic product (GDP) due to the unmet burden of surgical disease. However, no country-specific data currently exist. We aimed to estimate the costs to the Sierra Leone economy from death and disability which may have been averted by surgical care. We used estimates of total, met and unmet need from two main sources-a cluster randomised, cross-sectional, countrywide survey and a retrospective, nationwide study on surgery in Sierra Leone. We calculated estimated disability-adjusted life years from morbidity and mortality for the estimated unmet burden and modelled the likely economic impact using three different methods-gross national income per capita, lifetime earnings foregone and value of a statistical life. In 2012, estimated, discounted lifetime losses to the Sierra Leone economy from the unmet burden of surgical disease was between US$1.1 and US$3.8 billion, depending on the economic method used. These lifetime losses equate to between 23% and 100% of the annual GDP for Sierra Leone. 80% of economic losses were due to mortality. The incremental losses averted by scale up of surgical provision to the Lancet Commission target of 80% were calculated to be between US$360 million and US$2.9 billion. There is a large economic loss from the unmet need for surgical care in Sierra Leone. There is an immediate need for massive investment to counteract ongoing economic losses. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. 77 FR 45 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List Sierra Nevada...

    Federal Register 2010, 2011, 2012, 2013, 2014

    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...

  20. Spatial Patterns of Atmospherically Deposited Organic Contaminants at High Elevation in the Southern Sierra Nevada Mountains, California

    EPA Science Inventory

    Atmospherically deposited contaminants in the Sierra Nevada mountains of California have been implicated as adversely affecting amphibians and fish, yet the distributions of contaminants within the mountains are poorly known, particularly at high elevation. We tested the hypothe...

  1. Spatial Patterns of Atmospherically Deposited Organic Contaminants at High Elevation in the Southern Sierra Nevada Mountains, California

    EPA Science Inventory

    Atmospherically deposited contaminants in the Sierra Nevada mountains of California have been implicated as a factor adversely affecting biological resources such as amphibians and fish, yet the distributions of contaminants within the mountains are poorly known, particularly at...

  2. Summer evapotranspiration trends as related to time following logging of high elevation forest stands in Sierra Nevada

    Robert R. Ziemer

    1963-01-01

    Abstract - The quantity of summer soil moisture loss from logged forest openings was related to the length of time since the creation of the opening in a study made in the subalpine forest zone of the Sierra Nevada west-side near the Central Sierra Snow Laboratory, California, within the elevational range of 6,000 to 7,000 feet. Soil moisture depletion was measured in...

  3. Demography of the California spotted owl in the Sierra National Forest and Sequoia/Kings Canyon National Parks

    George N. Steger; Thomas E. Munton; Kenneth D. Johnson; Gary P. Eberlein

    2002-01-01

    Nine years (1990–1998) of demographic data on California spotted owls (Strix occidentalis occidentalis) in two study areas on the western slopes of the Sierra Nevada—one in the Sierra National Forest (SNF), the other in Sequoia/Kings Canyon National Parks (SNP)—are summarized. Numbers of territorial owls fluctuated from 85 to 50 in SNF and 80 to 58...

  4. Preliminary assessment of the moth (Lepidoptera: Heterocera) fauna of Rincon de Guadalupe, Sierra de Bacadehuachi, Sonora, Mexico

    John D. Palting

    2013-01-01

    The Sierra de Bacadéhuachi is a poorly sampled extension of the Sierra Madre Occidental (SMO) located in east-central Sonora near the town of Bacadéhuachi. Sampling of moths using mercury vapor and ultraviolet lights occurred in summer and fall 2011, and spring 2012 at Rincón de Guadalupe, located in pine-oak forest at 1680 m elevation. Approximately 400 taxa of moths...

  5. Landsat-Derived Estimates of Mangrove Extents in the Sierra Leone Coastal Landscape Complex during 1990-2016.

    PubMed

    Mondal, Pinki; Trzaska, Sylwia; de Sherbinin, Alex

    2017-12-21

    This study provides the first assessment of decadal changes in mangrove extents in Sierra Leone. While significant advances have been made in mangrove mapping using remote sensing, no study has documented long-term changes in mangrove extents in Sierra Leone-one of the most vulnerable countries in West Africa. Such understanding is critical for devising regional management strategies that can support local livelihoods. We utilize multi-date Landsat data and cloud computational techniques to quantify spatiotemporal changes in land cover, with focus on mangrove ecosystems, for 1990-2016 along the coast of Sierra Leone. We specifically focus on four estuaries-Scarcies, Sierra Leone, Yawri Bay, and Sherbro. We relied on the k-means approach for an unsupervised classification, and validated the classified map from 2016 using ground truth data collected from Sentinel-2 and high-resolution images and during field research (accuracy: 95%). Our findings indicate that the Scarcies river estuary witnessed the greatest mangrove loss since 1990 (45%), while the Sierra Leone river estuary experienced mangrove gain over the last 26 years (22%). Overall, the Sierra Leone coast lost 25% of its mangroves between 1990 and 2016, with the lowest coverage in 2000, during the period of civil war (1991-2002). However, natural mangrove dynamics, as supported by field observations, indicate the potential for regeneration and sustainability under carefully constructed management strategies.

  6. Landsat-Derived Estimates of Mangrove Extents in the Sierra Leone Coastal Landscape Complex during 1990–2016

    PubMed Central

    Trzaska, Sylwia

    2017-01-01

    This study provides the first assessment of decadal changes in mangrove extents in Sierra Leone. While significant advances have been made in mangrove mapping using remote sensing, no study has documented long-term changes in mangrove extents in Sierra Leone—one of the most vulnerable countries in West Africa. Such understanding is critical for devising regional management strategies that can support local livelihoods. We utilize multi-date Landsat data and cloud computational techniques to quantify spatiotemporal changes in land cover, with focus on mangrove ecosystems, for 1990–2016 along the coast of Sierra Leone. We specifically focus on four estuaries—Scarcies, Sierra Leone, Yawri Bay, and Sherbro. We relied on the k-means approach for an unsupervised classification, and validated the classified map from 2016 using ground truth data collected from Sentinel-2 and high-resolution images and during field research (accuracy: 95%). Our findings indicate that the Scarcies river estuary witnessed the greatest mangrove loss since 1990 (45%), while the Sierra Leone river estuary experienced mangrove gain over the last 26 years (22%). Overall, the Sierra Leone coast lost 25% of its mangroves between 1990 and 2016, with the lowest coverage in 2000, during the period of civil war (1991–2002). However, natural mangrove dynamics, as supported by field observations, indicate the potential for regeneration and sustainability under carefully constructed management strategies. PMID:29267247

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

    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. Bedrock river networks of the Sierra Nevada, USA record westward tilting, large-scale drainage area loss, and distinct patterns and causes of stream incision between the northern and southern Sierra

    NASA Astrophysics Data System (ADS)

    Beeson, H. W.; McCoy, S. W.

    2017-12-01

    The timing, rates, and spatial patterns of elevation change in the Sierra Nevada, California, USA, has been the subject of vigorous debate with multiple lines of evidence supporting the contrasting hypotheses that (1) the Sierra has been topographically high throughout the Cenozoic and (2) that the range has experienced a pulse of late Cenozoic uplift. We combined 2-D landscape evolution modeling with topographic analysis of the Sierra Nevada to investigate whether river networks dissecting the range record a change in tectonic forcing during the late Cenozoic. Specifically, we quantify basin geometry, including its area-channel length scaling relationship, fluvial channel steepness, and the spatial distributions of knickzones. We show that, throughout the Sierra, short equilibrated reaches near the mountain front are consistent with an ongoing westward tilt. However, the disequilibrium forms of river profiles north of the Kaweah River reflect large-scale drainage area loss due to network beheading by the Sierra Frontal Fault and/or reestablishment of a fluvial network on an inclined planar surface. Despite these similarities along the length of the range, river network analysis reveals striking differences north and south of approximately 37° N. In the northern Sierra, topographic asymmetry of drainage divides and large differences in cross-divide steady-state elevation suggest mobile divides. Additionally, the broad distribution of normalized knickzone locations, variability in channel steepness and basin shape, and the prevalence of anomalous topology, narrow basins, unadjusted captured reaches, and wind gaps is consistent with large-scale drainage reorganization following incision into an inclined planar surface. In contrast, in the southern Sierra, drainage divides appear more stable and knickzone locations are tightly distributed. We suggest that, although the northern Sierra may currently be tilting westward, the presence of large knickzones and deeply

  9. Comprehensive Yet Scalable Health Information Systems for Low Resource Settings: A Collaborative Effort in Sierra Leone

    PubMed Central

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

    2010-01-01

    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. PMID:21347003

  10. SIERRA Code Coupling Module: Arpeggio User Manual Version 4.44

    SciT

    Subia, Samuel R.; Overfelt, James R.; Baur, David G.

    2017-04-01

    The SNL Sierra Mechanics code suite is designed to enable simulation of complex multiphysics scenarios. The code suite is composed of several specialized applications which can operate either in standalone mode or coupled with each other. Arpeggio is a supported utility that enables loose coupling of the various Sierra Mechanics applications by providing access to Framework services that facilitate the coupling. More importantly Arpeggio orchestrates the execution of applications that participate in the coupling. This document describes the various components of Arpeggio and their operability. The intent of the document is to provide a fast path for analysts interested inmore » coupled applications via simple examples of its usage.« less

  11. Climate controls on forest productivity along the climate gradient of the western Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Kelly, A. E.; Goulden, M. L.

    2010-12-01

    The broad climate gradient of the slopes of the western Sierra Nevada mountains supports ecosystems spanning extremes of productivity, biomass, and function. We are using this natural environmental gradient to understand how climate controls NPP, aboveground biomass, species' range limits, and phenology. Our experimental approach combines eddy covariance, sap flow, dendrometer, and litterfall measurements in combination with soil and hydrological data from the Southern Sierra Critical Zone Observatory (SSCZO). We have found that above about 2500 m, forest productivity is limited by winter cold, while below 1200 m, productivity is likely limited by summer drought. The sweet spot between these elevations has a nearly year-long growing season despite a snowpack that persists for as long as six months. Our results show that small differences in temperature can markedly alter the water balance and productivity of mixed conifer forests.

  12. Late Quaternary offset of alluvial fan surfaces along the Central Sierra Madre Fault, southern California

    Burgette, Reed J.; Hanson, Austin; Scharer, Katherine M.; Midttun, Nikolas

    2016-01-01

    The Sierra Madre Fault is a reverse fault system along the southern flank of the San Gabriel Mountains near Los Angeles, California. This study focuses on the Central Sierra Madre Fault (CSMF) in an effort to provide numeric dating on surfaces with ages previously estimated from soil development alone. We have refined previous geomorphic mapping conducted in the western portion of the CSMF near Pasadena, CA, with the aid of new lidar data. This progress report focuses on our geochronology strategy employed in collecting samples and interpreting data to determine a robust suite of terrace surface ages. Sample sites for terrestrial cosmogenic nuclide and luminescence dating techniques were selected to be redundant and to be validated through relative geomorphic relationships between inset terrace levels. Additional sample sites were selected to evaluate the post-abandonment histories of terrace surfaces. We will combine lidar-derived displacement data with surface ages to estimate slip rates for the CSMF.

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

    PubMed

    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.

  14. SR-71A - in Flight over Southern Sierra Nevada Mountains

    NASA Technical Reports Server (NTRS)

    1997-01-01

    NASA Dryden Flight Research Center's SR-71A, tail number 844, banks away over the Sierra Nevada mountains after air refueling from a USAF tanker during a 1997 flight. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena, California. An upward-looking ultraviolet

  15. Ecology of the Scorpion, Microtityus jaumei in Sierra de Canasta, Cuba

    PubMed Central

    Cala-Riquelme, Franklyn; Colombo, Marco

    2011-01-01

    An assessment of the population dynamics of Microtityus jaumei Armas (Scorpiones: Buthidae) on the slopes south of Sierra de Canasta, Guantánamo Province, Cuba show an increase in activity over the year (≤ 0.05). The activity peak is related to the reproductive period from June to November. The abundance of scorpions was significantly related to density of the canopy and thickness of the substrate. PMID:21870972

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

    PubMed Central

    Blewitt, Geoffrey; Kreemer, Corné

    2016-01-01

    Abstract 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. PMID:27917328

  17. Correlations and Areal Distribution of the Table Mountain Formation, Stanislaus Group; Central Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Torrez, G.; Carlson, C. W.; Putirka, K. D.; Pluhar, C. J.; Sharma, R. K.

    2011-12-01

    Late Cenozoic evolution of the western Cordillera is a matter of ongoing debate in geologic studies. Volcanic deposits within, and adjacent to the Sierra Nevada have played a significant role in many of these debates. With local faulting coincident with eruption of members of the Stanislaus Group at ca. 38°N, the composition and correlation of these volcanics can greatly aid our understanding of Sierra Nevada tectonics. At the crest of the central Sierra Nevada, 23 trachyandesite lava flows of the Table Mountain Formation, dated at ~10 Ma, cap Sonora Peak. These 23 flows compose the thickest and most complete known stratigraphic section of the Table Mountain Formation in the region. Located ~12 km east of Sonora Peak are 16 flows of trachyandesite at Grouse Meadow. We have collected a detailed set of geochemical and paleomagnetic data for flows of these two sections at Sonora Peak and Grouse Meadows in an attempt to correlate volcanic, paleomagnetic and structural events related to uplift and extension in the Sierra Nevada and the Walker Lane. Correlation of individual flows is possible based on: stratigraphic order, temporal gaps in deposition as determined by paleomagnetic remanence direction and nonconformities, and flow geochemistry. These correlations allow us to infer source localities, flow directions, and temporal changes in flow routes. The large number of flows present at Grouse Meadow provides an additional data set from which to correlate various localities in the region to those units not represented at Sonora Peak. Several flows which occur in the upper portions of the Sonora Peak and Grouse Meadow stratigraphic sections do not correlate between these localities. The causes of stratigraphic discontinuity potentially represent: tectonic isolation across the Sierran Crest, topographic isolation by the emplacement of younger flows, or the combination of the two. Additional to the correlation of individual flows at these localities, this study shows a

  18. Mountain lions: preliminary findings on home-range use and density, central Sierra Nevada

    Donald L. Neal; George N. Steger; Ronald C. Bertram

    1987-01-01

    Between August 1983 and December 1985, 19 mountain lions were captured, radio equipped, and monitored daily within a portion of the North Kings deer herd range on the west slope of the central Sierra Nevada in California. The density of adult mountain lions was estimated to be one per 33.3 km²; that of adults and kittens together was estimated to be one per 20...

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Distance, accessibility and costs. Decision-making during childbirth in rural Sierra Leone: A qualitative study.

    PubMed

    Treacy, Laura; Bolkan, Håkon A; Sagbakken, Mette

    2018-01-01

    Sierra Leone has one of the highest maternal mortality ratios in the world. Efforts to reduce maternal mortality have included initiatives to encourage more women to deliver at health facilities. Despite the introduction of the free health care initiative for pregnant women, many women still continue to deliver at home, with few having access to a skilled birth attendant. In addition, inequalities between rural and urban areas in accessing and utilising health facilities persist. Further insight into how and why women make decisions around childbirth will help guide future plans and initiatives in improving maternal health in Sierra Leone. The objective of this study was to explore the perceptions and decision-making processes of women and their communities during childbirth in rural Sierra Leone. Data were collected through seven focus group discussions and 22 in-depth interviews with recently pregnant women and their community members in two rural villages. Data were analysed using systematic text condensation. Findings revealed that decision-making processes during childbirth are dynamic, intricate and need to be understood within the broader social context that they take place. Factors such as distance and lack of transport, perceived negative behaviour of hospital staff, direct and indirect financial obstacles, as well as the position of women in society all interact and influence how and what decisions are made. Pregnant women face multiple interacting vulnerabilities that influence their healthcare-seeking decisions during pregnancy and childbirth. Future initiatives to improve access and utilisation of safe healthcare services for pregnant women need to be based on adequate knowledge of structural constraints and health inequities that affect women in rural Sierra Leone.

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

    NASA Technical Reports Server (NTRS)

    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.

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

    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 <= 0. 01) for all the three GCMs in the period 2051-2099. The frequency of flood events above selected historical thresholds also increases under projections from CNRM CM3 and NCAR PCM1 climate models, while under the third scenario, GFDL CM2. 1, frequencies remain constant or decline slightly, owing to an overall drying trend. These increases appear to derive jointly from increases in heavy precipitation amount, storm frequencies, and days with more precipitation falling as 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

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

    PubMed Central

    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

    2016-01-01

    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. PMID:27035948

  4. Ecology of the scorpion, Microtityus jaumei in Sierra de Canasta, Cuba.

    PubMed

    Cala-Riquelme, Franklyn; Colombo, Marco

    2011-01-01

    An assessment of the population dynamics of Microtityus jaumei Armas (Scorpiones: Buthidae) on the slopes south of Sierra de Canasta, Guantánamo Province, Cuba show an increase in activity over the year (≤ 0.05). The activity peak is related to the reproductive period from June to November. The abundance of scorpions was significantly related to density of the canopy and thickness of the substrate.

  5. Hydrologic Response and Watershed Sensitivity to Climate Warming in California's Sierra Nevada

    PubMed Central

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

    2010-01-01

    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°, 4°, and 6°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. PMID:20368984

  6. Groundwater quality in the Mokelumne, Cosumnes, and American River Watersheds, Sierra Nevada, California

    Fram, Miranda S.; Shelton, Jennifer L.

    2018-03-23

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Program’s Priority Basin Project assesses the quality of groundwater resources used for drinking water supply and increases public access to groundwater-quality information. In the Mokelumne, Cosumnes, and American River Watersheds of the Sierra Nevada, many rural households rely on private wells for their drinking-water supplies.

  7. Recent projections of 21st-century climate change and watershed responses in the Sierra Nevada

    Michael D. Dettinger; Daniel R. Cayan; Noah Knowles; Anthony Westerling; Mary K. Tyree

    2004-01-01

    In the near future, the Sierra Nevada’s climate is projected to experience a new form of climate change due to increasing concentrations of greenhouse gases in the global atmosphere from the burning of fossil fuels and other human activities. If the changes occur, they presumably will be added to the large interannual and longer-term climate variations in the recent...

  8. Interpretation of snowcover from satellite imagery for use in water supply forecasts in the Sierra Nevada

    NASA Technical Reports Server (NTRS)

    Brown, A. J.; Hannaford, J. F.

    1975-01-01

    The California ASVT test area is composed of two study areas; one in Northern California covering the Upper Sacramento and Feather River Basins, and the other covering the Southern Sierra Basins of the San Joaquin, Kings, Kaweah, Tule, and Kern Rivers. Experiences of reducing snowcover from satellite imagery; the accuracy of present water supply forecast schemes; and the potential advantages of introducing snowcover into the forecast procedures are described.

  9. 78 FR 79688 - Newmont Nevada Energy Investment LLC v. Sierra Pacific Power Company; Notice of Complaints

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-31

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL14-16-000] Newmont Nevada Energy Investment LLC v. Sierra Pacific Power Company; Notice of Complaints Take notice that on December 23, 2013, pursuant to sections 206 and 306 of the Federal Power Act (FPA), 16 U.S.C. 824e, and 825e and Rule 206 of the Rules of Practice and...

  10. The source provenance of an obsidian Eden point from Sierra County, New Mexico

    DOE PAGES

    Dolan, Sean Gregory; Berryman, Judy; Shackley, M. Steven

    2016-01-02

    Eden projectile points associated with the Cody complex are underrepresented in the late Paleoindian record of the American Southwest. EDXRF analysis of an obsidian Eden point from a site in Sierra County, New Mexico demonstrates this artifact is from the Cerro del Medio (Valles Rhyolite) source in the Jemez Mountains. Lastly, we contextualize our results by examining variability in obsidian procurement practices beyond the Cody heartland in southcentral New Mexico.

  11. Improving access to surgery in a developing country: experience from a surgical collaboration in Sierra Leone.

    PubMed

    Kushner, Adam L; Kamara, Thaim B; Groen, Reinou S; Fadlu-Deen, Betsy D; Doah, Kisito S; Kingham, T Peter

    2010-01-01

    Although surgery is increasingly recognized as an essential component of primary health care, there has been little documentation of surgical programs in low- and middle-income countries. Surgeons OverSeas (SOS) is a New York-based organization with a mission to save lives in developing countries by improving surgical care. This article highlights the surgical program in Sierra Leone as a possible model to improve access to surgery. An SOS team conducted a needs assessment of surgical capacity in Sierra Leone in February 2008. Interventions were then developed and programs were implemented. A follow-up assessment was conducted in December 2009, which included interviews of key Sierra Leone hospital personnel and a review of operating room log books. Based on an initial needs assessment, a program was developed that included training, salary support, and the provision of surgical supplies and equipment. Two 3-day workshops were conducted for a total of 44 health workers, salary support given to over 100 staff, and 2 containers of supplies and equipment were donated. Access to surgery, as measured by the number of major operations at Connaught Hospital, increased from 460 cases in 2007 to 768 cases in 2009. The SOS program in Sierra Leone highlights a method for improving access to surgery that incorporates an initial needs assessment with minimal external support and local staff collaboration. The program functions as a catalyst by providing training, salary support, and supplies. The beneficial results of the program can then be used to advocate for additional resources for surgery from policy makers. This model could be beneficial in other resource-poor countries in which improved access to surgery is desired. Copyright 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  12. Nationally representative household survey of surgery and mortality in Sierra Leone.

    PubMed

    Kwon, Steve; Groen, Reinou S; Kamara, Thaim B; Cassidy, Laura D; Samai, Mohamed; Yambasu, Sahr E; Kushner, Adam L

    2013-08-01

    There is limited evidence to characterize the burden of unmet need of surgical diseases in low- and middle-income countries. The purpose of this study was to determine rate of deaths attributable to a surgical condition and reasons for not seeking surgical care in Sierra Leone. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) is a survey tool developed collaboratively to be used for cross-sectional data collection of the prevalence of surgical conditions in any country. A population-weighted cluster-sample household survey was conducted throughout Sierra Leone in 2012 using the SOSAS survey tool. Total of 1,840 households (11,870 individuals) were sampled, yielding a 98.3 % response rate. Overall, there were 709 total deaths reported (6.0 %). The mean age at death was 36.4 ± 30.1 years: 330 (46.6 %) were female. Most deaths occurred at home (58.1 % vs. 34.1 % in hospitals). Of the 709 deaths, 237 (33.4 %) were associated with conditions included in our predefined surgical disease category. Abdominal distension/pain was the most commonly associated surgical condition (13.9 %) followed by perinatal bleeding/illness (6.0 %). Among the 237 with surgical conditions, 51 (21.9 %) did not seek medical care, most commonly because of a lack of money (35.3 %) or inability to provide timely care (37.3 %). A large proportion of deaths in Sierra Leone was associated with surgical conditions, the majority of which did not undergo surgical intervention. Our results indicate that to remove barriers to effective surgical care in Sierra Leone policymakers should first focus on relieving financial burdens and increasing access to timely surgical care.

  13. Medium and large mammals in the Sierra La Madera, Sonora, Mexico

    Erick Oswaldo Bermudez-Enriquez; Rosa Elena Jimenez-Maldonado; Gertrudis Yanes-Arvayo; Maria de la Paz Montanez-Armenta; Hugo Silva-Kurumiya

    2013-01-01

    Sierra La Madera is a Sky Island mountain range in the Madrean Archipelago. It is in Fracción V of the Ajos-Bavispe CONANP Reserve in the Municipios (= Counties) of Cumpas, Granados, Huásabas, Moctezuma, and Villa Hidalgo. Medium and large mammals were inventoried using camera traps. Eighteen Wild View 2® camera traps were deployed during four sampling periods: August...

  14. Effects of non-native trout on Pacific treefrogs (Hyla regilla) in the Sierra Nevada.

    K.R. Matthews; K.L. Pope; H. K. Preisler; R.A. Knapp

    2001-01-01

    We used analyses based on surveys of . 1700 water bodies in a 100,000-ha area in the John Muir Wilderness (JMW) and Kings Canyon National Park (KCNP) to determine the influence of nonnative trout on the distribution and abundance of Hyla regilla in the High Sierra Nevada. At the landscape scale (JMW compared to KCNP), a negative relationship between trout and frogs in...

  15. Magma mixing in granitic rocks of the central Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Reid, John B.; Evans, Owen C.; Fates, Dailey G.

    1983-12-01

    The El Capitan alaskite exposed in the North American Wall, Yosemite National Park, was intruded by two sets of mafic dikes that interacted thermally and chemically with the host alaskite. Comparisons of petrographic and compositional data for these dikes and alaskite with published data for Sierra Nevada plutons lead us to suggest that mafic magmas were important in the generation of the Sierra Nevada batholith. Specifically, we conclude that: (1) intrusion of mafic magmas in the lower crust caused partial melting and generation of alaskite (rhyolitic) magmas; (2) interaction between the mafic and felsic magmas lead to the observed linear variation diagrams for major elements; (3) most mafic inclusions in Sierra Nevada plutons represent chilled pillows of mafic magmas, related by fractional crystallization and granitoid assimilation, that dissolve into their felsic host and contaminate it to intermediate (granodioritic) compositions; (4) vesiculation of hydrous mafic magma upon chilling may allow buoyant mafic inclusions and their disaggregation products to collect beneath a pluton's domed ceiling causing the zoning (mafic margins-to-felsic core) that these plutons exhibit.

  16. 10Be exposure dating of Holocene moraines in the Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Hidy, Alan; Zimmerman, Susan; Finkel, Robert; Schaefer, Jeorg; Clark, Douglas

    2016-04-01

    Constraint on the extent and timing of Holocene glaciations is critical to addressing standing hypotheses that ascribe climatic fluctuations to changes in atmospheric and oceanic circulation patterns, or anthropogenic forcing. In the terrestrial record, such constraint typically relies on chronologies obtained from 10Be exposure dating of moraine deposits. However, the short exposure time of Holocene moraines, particularly those formed during the Little Ice Age (LIA), makes obtaining precise chronologies extremely challenging. To date, only a handful of LIA deposits in two locations (New Zealand and the Swiss Alps) have been successfully dated with 10Be. Here, we report new 10Be exposure ages from LIA and Neoglacial moraines from multiple sites in the Sierra Nevada (Lyell, Maclure, and Palisade glaciers). The Sierran LIA record will be compared to those from New Zealand and the Swiss Alps to test whether LIA deglaciation was globally synchronous. This result would support the contention that the LIA was terminated by anthropogenically-driven warming. Chronology from the neoglacial deposits will be used to test whether the timing of the return to glacial conditions in the Sierras correlates to a southward shift in the Intertropical Convergence Zone, which has been hypothesized to increase El Nino-like conditions in the Pacific Ocean. This record should be ideal for testing this hypothesis since precipitation in the Sierras is highly sensitive to El Nino conditions.

  17. Airborne SAR determination of relative ages of Walker Valley moraines, eastern Sierra Nevada

    NASA Technical Reports Server (NTRS)

    Fox, A.; Isacks, B.; Bloom, A.; Fielding, E.; Mcmurry, D.

    1991-01-01

    A regional study of the distribution and elevations of Pleistocene moraines in the Andes requires a method of determining relative age from space. One of our primary objectives is to establish the relative chronology of major climatic events responsible for glaciation in the Andes and other regions that are difficult to access on the ground and where suitable material for absolute age determination is lacking. The sensitivity of radar to surface roughness makes it possible to develop a remotely-based relative dating technique for landforms for which surface age and roughness can be correlated. We are developing such a technique with Airborne Synthetic Aperture Radar (AIRSAR) imagery of the eastern Sierra Nevada where independent evidence is available for the ages and physical characteristics of moraines. The Sierra Nevada moraines are similar in form and environmental setting to Andean moraines that we have targeted for study during the pending Shuttle Imaging Radar-C (SIR-C) mission. SAR imagery is used to differentiate the ages of five moraine sequences of Walker Valley in the eastern Sierra Nevada. Other aspects of this investigation are briefly discussed.

  18. Good laboratory practices guarantee biosafety in the Sierra Leone-China friendship biosafety laboratory.

    PubMed

    Wang, Qin; Zhou, Wei-Min; Zhang, Yong; Wang, Huan-Yu; Du, Hai-Jun; Nie, Kai; Song, Jing-Dong; Xiao, Kang; Lei, Wen-Wen; Guo, Jian-Qiang; Wei, He-Jiang; Cai, Kun; Wang, Yan-Hai; Wu, Jiang; Kamara, Gerard; Kamara, Idrissa; Wei, Qiang; Liang, Mi-Fang; Wu, Gui-Zhen; Dong, Xiao-Ping

    2016-06-23

    The outbreak of Ebola virus disease (EVD) in West Africa between 2014 and 2015 was the largest EDV epidemic since the identification of Ebola virus (EBOV) in 1976, and the countries most strongly affected were Sierra Leone, Guinea, and Liberia. The Sierra Leone-China Friendship Biological Safety Laboratory (SLE-CHN Biosafety Lab), a fixed Biosafety Level 3 laboratory in the capital city of Sierra Leone, was established by the Chinese government and has been active in EBOV detection since 11 March 2015. Complete management and program documents were created for the SLE-CHN Biosafety Lab, and it was divided into four zones (the green, yellow, brown, and red zones) based on the risk assessment. Different types of safe and appropriate personnel protection equipment (PPE) are used in different zones of the laboratory, and it fully meets the Biosafety Level 3 laboratory standards of the World Health Organization. Good preparedness, comprehensive risk assessment and operation documents, appropriate PPE, effective monitoring and intensive training, together with well-designed and reasonable laboratory sectioning are essential for guaranteeing biosafety.

  19. Evidence for nutrient enrichment of high-elevation lakes in the Sierra Nevada, California

    Sickman, James O.; Melack, John M.; Clow, David W.

    2003-01-01

    Long-term measurements (1983-2001) of nutrients and seston in Emerald Lake (Sierra Nevada, California) have revealed ecologically significant patterns. Nitrate, both during spring runoff and during growing seasons, declined from 1983 through 1995. Declining snowmelt nitrate was caused primarily by changes in snow regime induced by the 1987-1992 drought: years with shallow, early melting snowpacks had lower snowmelt nitrate concentrations owing to less labile N production in catchment soils and longer plant growing seasons. However, nitrate declines during growing seasons carried through the wetter years of 1993-2000 and are likely the result of increased P loading to the lake and the release of phytoplankton from P limitation. Contemporaneous with these changes was an increase in algal biomass and a shift from P limitation toward more frequent N limitation of phytoplankton abundance. Particulate carbon concentrations in the late 1990s were two- to threefold greater than in the early 1980s. These trends were reflected in a larger set of Sierra Nevada lakes sampled as part of synoptic surveys (n = 28). Between 1985 and 1999, nitrate decreased and total P increased in >70% of the lakes sampled. Our data suggest that lakes throughout the Sierra Nevada are experiencing measurable eutrophication in response to the atmospheric deposition of nutrients.

  20. Rapid assessment of Ebola infection prevention and control needs--six districts, Sierra Leone, October 2014.

    PubMed

    Pathmanathan, Ishani; O'Connor, Katherine A; Adams, Monica L; Rao, Carol Y; Kilmarx, Peter H; Park, Benjamin J; Mermin, Jonathan; Kargbo, Brima; Wurie, Alie H; Clarke, Kevin R

    2014-12-12

    As of October 31, 2014, the Sierra Leone Ministry of Health and Sanitation had reported 3,854 laboratory-confirmed cases of Ebola virus disease (Ebola) since the outbreak began in May 2014; 199 (5.2%) of these cases were among health care workers. Ebola infection prevention and control (IPC) measures are essential to interrupt Ebola virus transmission and protect the health workforce, a population that is disproportionately affected by Ebola because of its increased risk of exposure yet is essential to patient care required for outbreak control and maintenance of the country's health system at large. To rapidly identify existing IPC resources and high priority outbreak response needs, an assessment by CDC Ebola Response Team members was conducted in six of the 14 districts in Sierra Leone, consisting of health facility observations and structured interviews with key informants in facilities and government district health management offices. Health system gaps were identified in all six districts, including shortages or absence of trained health care staff, personal protective equipment (PPE), safe patient transport, and standardized IPC protocols. Based on rapid assessment findings and key stakeholder input, priority IPC actions were recommended. Progress has since been made in developing standard operating procedures, increasing laboratory and Ebola treatment capacity and training the health workforce. However, further system strengthening is needed. In particular, a successful Ebola outbreak response in Sierra Leone will require an increase in coordinated and comprehensive district-level IPC support to prevent ongoing Ebola virus transmission in household, patient transport, and health facility settings.

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

    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.

  2. Caligus fajerae n. sp. (Copepoda: Caligidae) parasitic on the Pacific sierra Scomberomurus sierra Jordan & Starks (Actinopterygii: Scombridae) in the Pacific Ocean off Mexico.

    PubMed

    Morales-Serna, Francisco Neptalí; Oceguera-Figueroa, Alejandro; Tang, Danny

    2017-10-01

    A new species of parasitic copepod, Caligus fajerae n. sp. (Caligidae), is described from Scomberomorus sierra Jordan & Starks (Scombridae) caught off the northwestern coast of Mexico. The new species morphologically resembles Caligus cybii Bassett-Smith, 1898, Caligus kanagurta Pillai, 1961, Caligus pelamydis Krøyer, 1863 and Caligus robustus Bassett-Smith, 1898, all of which have been reported from scombrid hosts. Caligus fajerae n. sp. differs from these species by having spinules on the abdomen and caudal ramus, two processes on the proximal antennulary segment, fine striations on the claw of the antenna and maxilliped, a stouter and more recurved maxillulary dentiform process, shorter tines on the sternal furca, two additional patches of spinules on the distal endopodal segment of leg 2, a sclerotised lobe on the anteromedian surface of the leg 3 protopod and serrations on both margins of the first exopodal spine of leg 3. Analysis of the DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 gene for Caligus fajerae n. sp. and 28 congeners, including C. pelamydis and C. robustus, showed that the new species grouped with Caligus belones Krøyer, 1863 (with 20% divergence), a species known to occur predominantly on needlefishes. Caligus fajerae n. sp. is the fifth species of Caligus reported from S. sierra. An updated host-parasite list for Caligus spp. on scombrids is provided.

  3. Moho Structure of the Central Sierra Nevada From an EarthScope Flex Array Deployment

    NASA Astrophysics Data System (ADS)

    Burdick, S.; Zandt, G.; Gilbert, H.; Jones, C.; Owens, T.

    2005-12-01

    Findings from the southern Sierra Nevada (south of 37 degrees north) show that the crustal thickness in the southern Sierra Nevada range does not obey an Airy isostasy model. Receiver function data show that the crustal thickness generally increases across the range from the high eastern peaks to the low western foothills, and the Moho discontinuity disappears beneath parts of the western foothills. This disappearance of the Moho has been attributed to the entrainment of the crust into the mantle by the convective removal of the southern batholithic root during the past 3-4 M yrs (Zandt et al., Nature, 2004). Other possible causes of Moho disappearance include a very gradational, or even inverted, impedance contrast due to lower crustal or upper mantle wavespeed anomalies. During the summer of 2005, the Sierra Nevada Earthscope Project (SNEP) has deployed an Earthscope flex array of over forty broadband seismometers with 25 km spacing, designed to constrain lithospheric structure of the central Sierra Nevada between the latitudes of approximately 37 to 38 degrees north. We will report on a receiver function study to better define the boundaries of the Moho "hole" to the north. Initial receiver functions from the first stations deployed mainly on the western and eastern flanks of the range show a northward continuation of both the "hole" under the western margin and a high amplitude Moho under the eastern flank of the range. This new observation suggests either the Moho disappearance is unrelated to the convective removal of the southern root or that root removal has affected the Sierra Nevada significantly farther north than suggested by presently available volcanic and xenolith evidence. Receiver functions collected from SNEP data will be processed into move-out corrected depth stacks in order to present a more complete map of Moho depth and amplitude beneath the region. To quantify the range of impedance contrasts capable of producing the observed variability in

  4. Volcanologic and petrologic evolution of Antuco-Sierra Velluda, Southern Andes, Chile

    NASA Astrophysics Data System (ADS)

    Martínez, Paola; Singer, Brad S.; Roa, Hugo Moreno; Jicha, Brian R.

    2018-01-01

    The Andean Southern Volcanic Zone comprises > 30 active arc front volcanoes that grew over periods of hundreds of thousands of years. Quantifying the rates at which these volcanoes grow is key to appreciating geological hazards, clarifying petrologic evolution, and exploring possible relationships between volcanism, ice loading, and climate. The integration of precise geochronology and geologic mapping, together with new lava compositions and volume estimates, reveal the evolution of the Antuco-Sierra Velluda volcanic complex at 37.2°S. Thirty-one new 40Ar/39Ar age determinations illuminate a punctuated eruptive history that spans at least 430 kyr. Sierra Velluda comprises 130 km3 and began to grow prior to 426.8 ka. A lacuna in the volcanic record between 343.5 and 150.4 ka coincides with glaciations associated with marine isotope stages (MIS) 10 and 8, although shallow intrusions were emplaced at 207.0 and 190.0 ka. Antuco began to grow rapidly on the northeast flank of Sierra Velluda, erupting > 60 km3 of lava during three phases: (1) an early phase that began at 150.4 ka, (2) a post-MIS 2 phase between 16.3 and 6.2 ka, and (3) a post-sector collapse phase after 6.2 ka. Volcanism has been continuous during the last 100 kyr, with an average rate of cone growth during this period of 0.46 km3/kyr that has accelerated by about 50% during the past 6 kyr. Whereas Sierra Velluda erupted basaltic andesitic to andesitic (53.5 to 58.7 wt% SiO2) lavas, during the last expansion of glaciers between 130 and 17 ka, Early Antuco erupted a wider spectrum of lavas, ranging from basaltic andesite to dacite (52.0 to 64.5 wt% SiO2). Notably, eruptions following the last glacial termination at 17 ka produced basalts and basaltic andesites (50.9-53.7% SiO2), and following the 6.2 ka cone collapse they have been exclusively olivine basalt (50.9-53.0% SiO2) with > 5 wt% MgO. Thermodynamic and trace element modeling suggests that lavas from Sierra Velluda and Early Antuco reflect

  5. Arsenic and mercury contamination related to historical goldmining in the Sierra Nevada, California

    Alpers, Charles N.

    2017-01-01

    Arsenic (As) is a naturally occurring constituent in low-sulphide gold-quartz vein deposits, the dominant deposit type for lode mines in the Sierra Nevada Foothills (SNFH) gold (Au) province of California. Concentrations of naturally occurring mercury (Hg) in the SNFH Au province are low, but extensive use and loss of elemental Hg during amalgamation processing of ore from lode and placer Au deposits led to widespread contamination of Hg in the Sierra Nevada foothills and downstream areas, such as the Sacramento–San Joaquin Delta and San Francisco Bay. This review paper provides an overview of As and Hg contamination related to historical Au mining in the Sierra Nevada of California. It summarizes the geology, mineralogy, and geochemistry of the Au deposits, and provides information on specific areas where detailed studies have been done in association with past, ongoing, and planned remediation activities related to the environmental As and Hg contamination.Arsenic is a naturally occurring constituent in low-sulphide Au-quartz vein deposits, the dominant deposit type for lode mines in the Sierra Nevada Foothills (SNFH) Au province (Ashley 2002). Because of elevated concentrations of As in accessory iron-sulphide minerals including arsenopyrite (FeAsS) and arsenian pyrite (Fe(S,As)2), As is commonly a contaminant of concern in lode Au mine waste, including waste rock and mill tailings. The principal pathways of human As exposure from mine waste include ingestion of soil or drinking water, and inhalation of dust in contaminated areas (Mitchell 2014).Concentrations of naturally occurring Hg in the SNFH Au province are low, but extensive use and loss of elemental Hg during amalgamation processing of ore from lode and placer Au deposits (Churchill 2000) led to widespread contamination of Hg in the Sierra Nevada foothills and downstream areas, such as the Sacramento–San Joaquin Delta and San Francisco Bay (Alpers et al. 2005a). Conversion of Hg to monomethylmercury

  6. Spatiotemporal patterns of fault slip rates across the Central Sierra Nevada frontal fault zone

    NASA Astrophysics Data System (ADS)

    Rood, Dylan H.; Burbank, Douglas W.; Finkel, Robert C.

    2011-01-01

    Patterns in fault slip rates through time and space are examined across the transition from the Sierra Nevada to the Eastern California Shear Zone-Walker Lane belt. At each of four sites along the eastern Sierra Nevada frontal fault zone between 38 and 39° N latitude, geomorphic markers, such as glacial moraines and outwash terraces, are displaced by a suite of range-front normal faults. Using geomorphic mapping, surveying, and 10Be surface exposure dating, mean fault slip rates are defined, and by utilizing markers of different ages (generally, ~ 20 ka and ~ 150 ka), rates through time and interactions among multiple faults are examined over 10 4-10 5 year timescales. At each site for which data are available for the last ~ 150 ky, mean slip rates across the Sierra Nevada frontal fault zone have probably not varied by more than a factor of two over time spans equal to half of the total time interval (~ 20 ky and ~ 150 ky timescales): 0.3 ± 0.1 mm year - 1 (mode and 95% CI) at both Buckeye Creek in the Bridgeport basin and Sonora Junction; and 0.4 + 0.3/-0.1 mm year - 1 along the West Fork of the Carson River at Woodfords. Data permit rates that are relatively constant over the time scales examined. In contrast, slip rates are highly variable in space over the last ~ 20 ky. Slip rates decrease by a factor of 3-5 northward over a distance of ~ 20 km between the northern Mono Basin (1.3 + 0.6/-0.3 mm year - 1 at Lundy Canyon site) to the Bridgeport Basin (0.3 ± 0.1 mm year - 1 ). The 3-fold decrease in the slip rate on the Sierra Nevada frontal fault zone northward from Mono Basin is indicative of a change in the character of faulting north of the Mina Deflection as extension is transferred eastward onto normal faults between the Sierra Nevada and Walker Lane belt. A compilation of regional deformation rates reveals that the spatial pattern of extension rates changes along strike of the Eastern California Shear Zone-Walker Lane belt. South of the Mina Deflection

  7. Spatiotemporal Patterns of Fault Slip Rates Across the Central Sierra Nevada Frontal Fault Zone

    NASA Astrophysics Data System (ADS)

    Rood, D. H.; Burbank, D.; Finkel, R. C.

    2010-12-01

    We examine patterns in fault slip rates through time and space across the transition from the Sierra Nevada to the Eastern California Shear Zone-Walker Lane belt. At each of four sites along the eastern Sierra Nevada frontal fault zone between 38-39° N latitude, geomorphic markers, such as glacial moraines and outwash terraces, are displaced by a suite of range-front normal faults. Using geomorphic mapping, surveying, and Be-10 surface exposure dating, we define mean fault slip rates, and by utilizing markers of different ages (generally, ~20 ka and ~150 ka), we examine rates through time and interactions among multiple faults over 10-100 ky timescales. At each site for which data are available for the last ~150 ky, mean slip rates across the Sierra Nevada frontal fault zone have probably not varied by more than a factor of two over time spans equal to half of the total time interval (~20 ky and ~150 ky timescales): 0.3 ± 0.1 mm/yr (mode and 95% CI) at both Buckeye Creek in the Bridgeport basin and Sonora Junction; and 0.4 +0.3/-0.1 mm/yr along the West Fork of the Carson River at Woodfords. Our data permit that rates are relatively constant over the time scales examined. In contrast, slip rates are highly variable in space over the last ~20 ky. Slip rates decrease by a factor of 3-5 northward over a distance of ~20 km between the northern Mono Basin (1.3 +0.6/-0.3 mm/yr at Lundy Canyon site) and the Bridgeport Basin (0.3 ± 0.1 mm/yr). The 3-fold decrease in the slip rate on the Sierra Nevada frontal fault zone northward from Mono Basin reflects a change in the character of faulting north of the Mina Deflection as extension is transferred eastward onto normal faults between the Sierra Nevada and Walker Lane belt. A compilation of regional deformation rates reveal that the spatial pattern of extension rates changes along strike of the Eastern California Shear Zone-Walker Lane belt. South of the Mina Deflection, extension is accommodated within a diffuse zone of

  8. Plutonism in the central part of the Sierra Nevada Batholith, California

    Bateman, Paul C.

    1992-01-01

    The Sierra Nevada batholith comprises the plutonic rocks of Mesozoic age that underlie most of the Sierra Nevada, a magnificent mountain range that originated in the Cenozoic by the westward tilting of a huge block of the Earth's crust. Scattered intrusions west of the batholith in the western metamorphic belt of the Sierra Nevada and east of the Sierra Nevada in the Benton Range and the White and Inyo Mountains are satellitic to but not strictly parts of the Sierra Nevada batholith. Nevertheless, all the plutonic rocks are related in origin. The batholith lies along the west edge of the Paleozoic North American craton, and Paleozoic and early Mesozoic oceanic crust underlies its western margin. It was emplaced in strongly deformed but weakly metamorphosed strata ranging in age from Proterozoic to Cretaceous. Sedimentary rocks of Proterozoic and Paleozoic age crop out east of the batholith in the White and Inyo Mountains, and metamorphosed sedimentary and volcanic rocks of Paleozoic and Mesozoic age crop out west of the batholith in the western metamorphic belt. A few large and many small, generally elongate remnants of metamorphic rocks lie within the batholith. Sparse fossils from metasedimentary rocks and isotopic ages for metavolcanic rocks indicate that the metamorphic rocks in the remnants range in age from Early Cambrian to Early Cretaceous. Within the map area (the Mariposa 1 0 by 2 0 quadrangle), the bedding, cleavage, and axial surfaces of folds generally trend about N. 35 0 W., parallel to the long axis of the Sierra Nevada. The country rocks comprise strongly deformed but generally coherent sequences; however, some units in the western metamorphic belt may partly consist of melanges. Most sequences are in contact with other sequences, at least for short distances, but some sequences within the batholith are bounded on one or more sides by plutonic rocks. Proterozoic and Paleozoic sedimentary strata east of the Sierra Nevada and Paleozoic strata in

  9. High Compressive Stresses Near the Surface of the Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

    Observations and stress measurements in granitic rocks of the Sierra Nevada, California reveal strong compressive stresses parallel to the surface of the range at shallow depths. New overcoring measurements show high compressive stresses at three locations along an east-west transect through Yosemite National Park. At the westernmost site (west end of Tenaya Lake), the mean compressive stress is 1.9. At the middle site (north shore of Tenaya Lake) the mean compressive stress is 6.8 MPa. At the easternmost site (south side of Lembert Dome) the mean compressive stress is 3.0 MPa. The trend of the most compressive stress at these sites is within ~30° of the strike of the local topographic surface. Previously published hydraulic fracturing measurements by others elsewhere in the Sierra Nevada indicate surface-parallel compressive stresses of several MPa within several tens of meters of the surface, with the stress magnitudes generally diminishing to the west. Both the new and the previously published compressive stress magnitudes are consistent with the presence of sheeting joints (i.e., "exfoliation joints") in the Sierra Nevada, which require lateral compressive stresses of several MPa to form. These fractures are widespread: they are distributed in granitic rocks from the north end of the range to its southern tip and across the width of the range. Uplift along the normal faults of the eastern escarpment, recently measured by others at ~1-2 mm/yr, probably contributes to these stresses substantially. Geodetic surveys reveal that normal faulting flexes a range concave upwards in response to fault slip, and this flexure is predicted by elastic dislocation models. The topographic relief of the eastern escarpment of the Sierra Nevada is 2-4 km, and since alluvial fill generally buries the bedrock east of the faults, the offset of granitic rocks is at least that much. Compressive stresses of several MPa are predicted by elastic dislocation models of the range front

  10. Extreme daily precipitation in the Northern Sierra Precipitation 8-Station index: The combined impact of landfalling atmospheric rivers and the Sierra barrier jet

    NASA Astrophysics Data System (ADS)

    Cordeira, J. M.; Ralph, F. M.; Neiman, P. J.; Hughes, M.

    2014-12-01

    The Upper Sacramento River area is vital to California's water supply, and is susceptible to major floods. Recent studies indicate that orographic precipitation in this complex terrain involves both inland penetrating atmospheric rivers (ARs) and the Sierra barrier jet (SBJ). The southerly SBJ induces orographic precipitation along south-facing slopes in the Shasta region, whereas landfalling ARs ascend up and over the statically stable SBJ and induce orographic precipitation along west-facing upper slopes in the Northern Sierra Nevada. This paper explores the hypothesis that extreme daily precipitation here is controlled by the presence of both a landfalling AR and a SBJ. Three 10-year-long (2000-2011) observational datasets are used. ARs are identified from the Neiman et al. (2008) AR catalog that uses an SSM/I satellite-based AR-detection method from Ralph et al. (2004), whereas SBJ conditions are determined from Chico, CA wind profiler data using the method from Neiman et al. (2010). Extreme daily precipitation is identified from the average of 8 rain gauges spanning the region known as the "Northern Sierra 8-Station Index." The "index" is used by water managers to assess water supply. Extreme events are defined as the 50 largest daily precipitation totals in the index for the 10-year period (the top ~1.37%). These dates in the 8-station index are compared with the catalogs of landfalling ARs and SBJs. In summary, 46 of 50 (92%) extreme daily precipitation events are associated with landfalling ARs on either the day before or the day of precipitation, whereas 45 of 50 (90%) extreme daily precipitation events are associated with SBJ conditions. 38 of 50 (76%) extreme daily precipitation events are associated with both a landfalling AR and an SBJ. The 10 days with the largest daily precipitation in the index were all associated with both a landfalling AR and an SBJ. Thus, extreme daily precipitation in Northern California is strongly controlled by the presence of

  11. Comparison of social resistance to Ebola response in Sierra Leone and Guinea suggests explanations lie in political configurations not culture

    PubMed Central

    Wilkinson, Annie; Fairhead, James

    2017-01-01

    Abstract Sierra Leone and Guinea share broadly similar cultural worlds, straddling the societies of the Upper Guinea Coast with Islamic West Africa. There was, however, a notable difference in their reactions to the Ebola epidemic. As the epidemic spread in Guinea, acts of violent or everyday resistance to outbreak control measures repeatedly followed, undermining public health attempts to contain the crisis. In Sierra Leone, defiant resistance was rarer. Instead of looking to ‘culture’ to explain patterns of social resistance (as was common in the media and in the discourse of responding public health authorities) a comparison between Sierra Leone and Guinea suggests that explanations lie in divergent political practice and lived experiences of the state. In particular the structures of state authority through which the national epidemic response were organised integrated very differently with trusted institutions in each country. Predicting and addressing social responses to epidemic control measures should assess such political-trust configurations when planning interventions. PMID:28366999

  12. Uranium-lead isotopic ages from the Sierra Nevada Batholith, California

    NASA Astrophysics Data System (ADS)

    Chen, James H.; Moore, James G.

    1982-06-01

    This study provides new information on the timing and distribution of Mesozoic magmatic events in the Sierra Nevada batholithic complex chiefly between 36° and 37°N. latitude. U-Pb ages have been determined for 133 zircon and 7 sphene separates from 82 samples of granitoid rocks. Granitoid rocks in this area range in age from 217 to 80 m.y. Triassic intrusions are restricted to the east side of the batholith; Jurassic plutons occur south of the Triassic plutons east of the Sierra Nevada, as isolated masses within the Cretaceous batholith, and in the western foothills of the range; Cretaceous plutons form a continuous belt along the axis of the batholith and occur as isolated masses east of the Sierra Nevada. No granitic intrusions were emplaced for 37 m.y. east of the Sierra Nevada following the end of Jurassic plutonism. However, following emplacement of the eastern Jurassic granitoids, regional extension produced a fracture system at least 350 km long into which the dominantly mafic, calc-alkalic Independence dike swarm was intruded 148 m.y. ago. The dike fractures probably represents a period of regional crustal extension caused by a redistribution of the regional stress pattern accompanying the Nevadan orogeny. Intrusion of Cretaceous granitic plutons began in large volume about 120 m.y. ago in the western Sierra Nevada and migrated steadily eastward for 40 m.y. at a rate of 2.7 mm/y. This slow and constant migration indicates remarkably uniform conditions of subduction with perhaps downward migration of parent magma generation or a slight flattening of the subduction zone. Such steady conditions could be necessary for the production of large batholithic complexes such as the Sierra Nevada. The abrupt termination of plutonism 80 m.y. ago may have resulted from an increased rate of convergence of the American and eastern Pacific plates and dramatic flattening of the subduction zone. U-Pb ages of the Giant Forest-alaskite sequence in Sequoia National Park are

  13. Uranium-lead isotopic ages from the Sierra Nevada Batholith, California

    Chen, J.

    1982-01-01

    This study provides new information on the timing and distribution of Mesozoic magmatic events in the Sierra Nevada batholithic complex chiefly between 36° and 37°N. latitude. U-Pb ages have been determined for 133 zircon and 7 sphene separates from 82 samples of granitoid rocks. Granitoid rocks in this area range in age from 217 to 80 m.y. Triassic intrusions are restricted to the east side of the batholith; Jurassic plutons occur south of the Triassic plutons east of the Sierra Nevada, as isolated masses within the Cretaceous batholith, and in the western foothills of the range; Cretaceous plutons form a continuous belt along the axis of the batholith and occur as isolated masses east of the Sierra Nevada. No granitic intrusions were emplaced for 37 m.y. east of the Sierra Nevada following the end of Jurassic plutonism. However, following emplacement of the eastern Jurassic granitoids, regional extension produced a fracture system at least 350 km long into which the dominantly mafic, calc-alkalic Independence dike swarm was intruded 148 m.y. ago. The dike fractures probably represents a period of regional crustal extension caused by a redistribution of the regional stress pattern accompanying the Nevadan orogeny. Intrusion of Cretaceous granitic plutons began in large volume about 120 m.y. ago in the western Sierra Nevada and migrated steadily eastward for 40 m.y. at a rate of 2.7 mm/y. This slow and constant migration indicates remarkably uniform conditions of subduction with perhaps downward migration of parent magma generation or a slight flattening of the subduction zone. Such steady conditions could be necessary for the production of large batholithic complexes such as the Sierra Nevada. The abrupt termination of plutonism 80 m.y. ago may have resulted from an increased rate of convergence of the American and eastern Pacific plates and dramatic flattening of the subduction zone. U-Pb ages of the Giant Forest-alaskite sequence in Sequoia National Park are

  14. The Impacts of California's San Francisco Bay Area Gap on Precipitation Observed in the Sierra Nevada during Hmt and Calwater

    NASA Astrophysics Data System (ADS)

    White, A. B.; Neiman, P. J.; Creamean, J.; Coleman, T.; Ralph, F. M.; Prather, K. A.

    2014-12-01

    The National Oceanic and Atmospheric Administration (NOAA)'s Hydrometeorology Testbed (HMT; hmt.noaa.gov) conducts research on the meteorological and microphysical processes contributing to orographically enhanced precipitation. Some of HMT's precipitation research has been focused on a shallow rainfall process driven by collision-coalescence that often is undetected by the National Weather Service's operational scanning radar network, especially in the Western U.S., but that can produce rain rates that are capable of creating floods. Originally it was believed that this shallow rainfall process would occur more prevalently over the coastal mountain ranges than over the Sierra Nevada, since the higher mountains of the Sierra would force deeper atmospheric ascent and produce deeper precipitating cloud systems that extend well above the melting level. This notion was disproved when it was recently discovered that a site in the northern Sierra had nearly as large of a contribution to seasonal rainfall from this shallow rainfall process, on average, as did a habitually wet site in the coast range of Sonoma County north of San Francisco. This work examines this apparent paradox using observations collected during HMT and CalWater field campaigns. In particular, a case study from CalWater is used to highlight the interaction between a landfalling atmospheric river (AR) and the Sierra Barrier Jet (SBJ). The gap in coastal terrain associated with the San Francisco Bay area is shown to allow unprocessed, moisture-enhanced flow in the AR to reach the northern Sierra site, where the SBJ provides a lifting mechanism to create enhanced orographic precipitation as compared to a site in the southern Sierra, where AR-associated dynamics are weaker and AR flow is modified by upstream coastal terrain.

  15. Investigating Holocene Glacial and Pluvials Events in the Sierra Nevada of California

    NASA Astrophysics Data System (ADS)

    Ashford, J.; Sickman, J. O.; Lucero, D. M.; Kirby, M.; Gray, A. B.

    2016-12-01

    Understanding interannual and decadal variation in snowfall and extreme hydrologic events in the Sierra Nevada is hampered by short instrumental record and uncertainty caused by extrapolating paleoclimate data from lower elevation systems to the alpine snow deposition zone. Longer paleo records from high elevation systems are necessary to provide a more accurate record of snow water content and extreme precipitation events over millennial timescales that 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, an alpine lake in Sequoia National Park. The cores were split and characterized by P-wave velocity, magnetic susceptibility and density scanning along with grain-size analysis at 1-2 cm increments. Radiocarbon dates indicate that the Pear Lake cores contain a 13.5K year record of lake sediment. In contrast to other Sierra Nevada lakes previously cored by our group, high-resolution scanning revealed alternating fine grained, 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. The sand to gravel sized clasts are most likely associated with extreme precipitation events. Preliminary grain-size analysis results show evidence of isolated extreme hydrologic events and sections of increased event frequency which we hypothesize are the result of atmospheric rivers intersecting the southern Sierra Nevada outside of the snow covered period.

  16. Tertiary carbonate-dissolution cycles on the Sierra Leone Rise, eastern equatorial Atlantic Ocean

    Dean, W.E.; Gardner, J.V.; Cepek, P.

    1981-01-01

    Most of the Tertiary section on Sierra Leone Rise off northwest Africa consists of chalk, marl, and limestone that show cyclic alterations of clay-rich and clay-poor beds about 20-60 cm thick. On the basis of biostratigraphic accumulation rates, the cycles in Oligocene and Miocene chalk have periods which average about 44,000 years, and those in Eocene siliceous limestone have periods of 4000-27,000 years. Several sections were sampled in detail to further define the cycles in terms of content of CaCO3, clay minerals, and relative abundances of calcareous nannofossils. Extending information gained by analyses of Pleistocene cores from the continental margin of northwest Africa to the Tertiary cycles on Sierra Leone Rise, both dilution by noncarbonate material and dissolution of CaCO3 could have contributed to the observed relative variations in clay and CaCO3. However, dissolution of CaCO3 as the main cause of the carbonate-clay cycles on the Sierra Leone Rise, rather than dilution by clay, is suggested by the large amount of change (several thousand percent) in terrigenous influx required to produce the observed variations in amount of clay and by the marked increase in abundance of dissolution-resistant discoasters relative to more easily dissolved coccoliths in low-carbonate parts of cycles. The main cause of dissolution of CaCO3 was shoaling of the carbonate compensation depth (CCD) during the early Neogene and climatically induced fluctuations in the thickness of Antarctic Bottom Water. ?? 1981.

  17. Soilscapes in the dynamic tropical environments: The case of Sierra Madre del Sur

    NASA Astrophysics Data System (ADS)

    Krasilnikov, P. V.; García-Calderón, N. E.; Ibáñez-Huerta, A.; Bazán-Mateos, M.; Hernández-Santana, J. R.

    2011-12-01

    The paper gives an analysis of the pattern of soil cover of the Sierra Madre del Sur, one of the most complex physiographic regions of Mexico. It presents the results of the study of four latitudinal traverses across the region. We show that the distribution of soils in the Sierra Madre del Sur is associated with major climatic gradients, namely by vertical bioclimatic zonality in the mountains and by the effect of mountain shadow. Altitudinal distribution of soil-bioclimatic belts is complex due to non-uniform gradients of temperature and rainfall, and varies with the configuration of the mountain range. The distribution of soils is associated with the erosion and accumulation rates both on mountain slopes and in river valleys. The abundance of poorly developed soils in (semi)arid areas was ascribed to high erosion rate rather than to low pedogenetic potential. The formation of soil mosaic at a larger scale might be ascribed to the complex net of gully erosion and to the system of seismically triggered landslides of various ages. In the valleys, the distribution of soils depends upon the dynamics of sedimentation and erosion, which eventually exposes paleosols. Red-colored clayey sediments are remains of ancient weathering and pedogenesis. Their distribution is associated mainly with the intensity of recent slope processes. The soil cover pattern of the Sierra Madre del Sur cannot be explained by simplified schemes of bioclimatic zonality. The soil ranges can be explained by the distribution of climates, lithology, complex geological history of the region, and recent geomorphological processes.

  18. Potential environmental effects of pack stock on meadow ecosystems of the Sierra Nevada, USA

    Ostoja, Steven M.; Brooks, Matthew L.; Moore, Peggy E.; Berlow, Eric L.; Robert Blank,; Roche, Jim; Chase, Jennifer T.; Sylvia Haultain,

    2014-01-01

    Pack and saddle stock, including, but not limited to domesticated horses, mules, and burros, are used to support commercial, private and administrative activities in the Sierra Nevada. The use of pack stock has become a contentious and litigious issue for land management agencies in the region inter alia due to concerns over effects on the environment. The potential environmental effects of pack stock on Sierra Nevada meadow ecosystems are reviewed and it is concluded that the use of pack stock has the potential to influence the following: (1) water nutrient dynamics, sedimentation, temperature, and microbial pathogen content; (2) soil chemistry, nutrient cycling, soil compaction and hydrology; (3) plant individuals, populations and community dynamics, non-native invasive species, and encroachment of woody species; and (4) wildlife individuals, populations and communities. It is considered from currently available information that management objectives of pack stock should include the following: minimise bare ground, maximise plant cover, maintain species composition of native plants, minimise trampling, especially on wet soils and stream banks, and minimise direct urination and defecation by pack stock into water. However, incomplete documentation of patterns of pack stock use and limited past research limits current understanding of the effects of pack stock, especially their effects on water, soils and wildlife. To improve management of pack stock in this region, research is needed on linking measurable monitoring variables (e.g. plant cover) with environmental relevancy (e.g. soil erosion processes, wildlife habitat use), and identifying specific environmental thresholds of degradation along gradients of pack stock use in Sierra Nevada meadows.

  19. Assessing the spatial variability of mountain precipitation in California's Sierra Nevada using the Airborne Snow Observatory

    NASA Astrophysics Data System (ADS)

    Brandt, T.; Deems, J. S.; Painter, T. H.; Dozier, J.

    2016-12-01

    In California's Sierra Nevada, 10 or fewer winter storms are responsible for most of the annual precipitation, which falls mostly as snow. Presently, surface stations are used to measure the dynamics of mountain precipitation. However, even in places like the Sierra Nevada—one of the most gauged regions in the world—the paucity of surface stations can lead to large errors in precipitation thereby biasing both total water year and short-term streamflow forecasts. Remotely sensed snow depth and water equivalent, at a time scale that resolves storms, might provide a novel solution to the problems of: (1) quantifying the spatial variability of mountain precipitation; and (2) assessing gridded precipitation products that are mostly based on surface station interpolation. NASA's Airborne Snow Observatory (ASO), an imaging spectrometer and LiDAR system, has measured snow in the Tuolumne River Basin in California's Sierra Nevada for the past four years, 2013-2016; and, measurements will continue. Principally, ASO monitors the progression of melt for water supply forecasting, nonetheless, a number of flights bracketed storms allowing for estimates of snow accumulation. In this study we examine a few of the ASO recorded storms to determine both the basin and subbasin orographic effect as well as the spatial patterns in total precipitation. We then compare these results to a number of gridded climate products and weather models including: Daymet, the Parameter-elevation Regressions on Independent Slopes Model (PRISM), the North American Land Data Assimilation System (NLDAS-2), and the Weather Research and Forecasting (WRF) model. Finally, to put each ASO recorded storm into context, we use a climatology produced from snow pillows and the North American Regional Reanalysis (NARR) for 2014-2016 to examine key accumulation events, and classify storms based on their integrated water vapor flux.

  20. Hand-Hewn Granite Basins at Native American Saltworks, Sierra Nevada, California

    Moore, James G.; Diggles, Michael F.

    2009-01-01

    This site in the northern Sierra Nevada contains about 369 circular basins carved in fresh, glaciated granodioritic bedrock, with 325 basins crowded together in an area of 2,700 m2 on the main terrace. These terrace basins have a median average diameter of 125 cm (80 percent between 100 and 160 cm) and a median depth of 75-80 cm. They show a strong congruity to similar granitic basins in the southern Sierra Nevada apparently of Native American origin that are generally shallower. The basins are not of natural origin, as indicated by uniformity in size and nonoverlapping character of the basins; their common arrangement in lineaments; details of the shape of the basins; features in common with granite basins in the Southern Sierra Nevada; and, most compelling, the clustering of all the basins adjacent to (within 20 m of) two saline streams fed from a nearby salt spring. Native Americans apparently excavated them for the purpose of collecting saline water to evaporate and make salt for their use, and also as an animal attractant and a trade commodity. The flow of the salty streams delivers about 2.9 metric tons of salt per summer season to the basin area, and evaporation rates and the holding capacity of the basins indicate that about 2.5 tons of salt could be produced per season. This correspondence shows that the Indians made enough basins to exploit the resource. The site is the most impressive prehistoric saltworks yet discovered in North America and represents a unique departure from traditional hunter-gatherer activities to that of manufacturing. The actual grinding of so many basins in granite could not have been done without the labor of a concentrated population. It is believed that the work was accomplished over a long time by many people and with the use of fire to help disaggregate the bedrock.

  1. The Surgical Workforce and Surgical Provider Productivity in Sierra Leone: A Countrywide Inventory.

    PubMed

    Bolkan, Håkon A; Hagander, Lars; von Schreeb, Johan; Bash-Taqi, Donald; Kamara, Thaim B; Salvesen, Øyvind; Wibe, Arne

    2016-06-01

    Limited data exist on surgical providers and their scope of practice in low-income countries (LICs). The aim of this study was to assess the distribution and productivity of all surgical providers in an LIC, and to evaluate correlations between the surgical workforce availability, productivity, rates, and volume of surgery at the district and hospital levels. Data on surgeries and surgical providers from 56 (93.3 %) out of 60 healthcare facilities providing surgery in Sierra Leone in 2012 were retrieved between January and May 2013 from operation theater logbooks and through interviews with key informants. The Sierra Leonean surgical workforce consisted of 164 full-time positions, equal to 2.7 surgical providers/100,000 inhabitants. Non-specialists performed 52.8 % of all surgeries. In rural areas, the densities of specialists and physicians were 26.8 and 6.3 times lower, respectively, compared with urban areas. The average individual productivity was 2.8 surgeries per week, and varied considerably between the cadres of surgical providers and locations. When excluding four centers that only performed ophthalmic surgery, there was a positive correlation between a facility's volume of surgery and the productivity of its surgical providers (r s = 0.642, p < 0.001). Less than half of all of the surgery in Sierra Leone is performed by specialists. Surgical providers were significantly more productive in healthcare facilities with higher volumes of surgery. If all surgical providers were as productive as specialists in the private non-profit sector (5.1 procedures/week), the national volume of surgery would increase by 85 %.

  2. Fumarole/plume and diffuse CO2 emission from Sierra Negra caldera, Galapagos archipelago

    NASA Astrophysics Data System (ADS)

    Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.; Toulkeridis, Theofilos; Melián, Gladys; Barrancos, José; Virgili, Giorgio; Sumino, Hirochika; Notsu, Kenji

    2012-08-01

    Measurements of visible and diffuse gas emission were conducted in 2006 at the summit of Sierra Negra volcano, Galapagos, with the aim to better characterize degassing after the 2005 eruption. A total SO2 emission of 11 ± 2 t day-1 was derived from miniature differential optical absorption spectrometer (mini-DOAS) ground-based measurements of the plume emanating from the Mini Azufral fumarolic area, the most important site of visible degassing at Sierra Negra volcano. Using a portable multigas system, the H2S/SO2, CO2/SO2, and H2O/SO2 molar ratios in the Mina Azufral plume emissions were found to be 0.41, 52.2, and 867.9, respectively. The corresponding H2O, CO2, and H2S emission rates were 562, 394, and 3 t day-1, respectively. The total output of diffuse CO2 emissions from the summit of Sierra Negra volcano was 990 ± 85 t day-1, with 605 t day-1 being released by a deep source. The diffuse-to-plume CO2 emission ratio was about 1.5. Mina Azufral fumaroles released gasses containing 73.6 mol% of H2O; the main noncondensable components amounted to 97.4 mol% CO2, 1.5 mol% SO2, 0.6 mol% H2S, and 0.35 mol% N2. The higher H2S/SO2 ratio values found in 2006 as compared to those reported before the 2005 eruption reveal a significant hydrothermal contribution to the fumarolic emissions. 3He/4He ratios measured at Mina Azufral fumarolic discharges showed values of 17.88 ± 0.25 R A , indicating a mid-ocean ridge basalts (MORB) and a Galapagos plume contribution of 53 and 47 %, respectively.

  3. Child mental health in Sierra Leone: a survey and exploratory qualitative study.

    PubMed

    Yoder, Hélène N C; Tol, Wietse A; Reis, Ria; de Jong, Joop T V M

    2016-01-01

    This study complements the growing amount of research on the psychosocial impact of war on children in Sierra Leone by examining local perceptions of child mental health, formal and informal care systems, help-seeking behaviour and stigma. The study combined: (1) a nationwide survey of mental health care providers, with (2) exploratory qualitative research among service users and providers and other stakeholders concerned with child and adolescent mental health, with a particular emphasis on local explanations and stigma. Formal mental health care services are extremely limited resulting in an estimated treatment gap of over 99.8 %. Local explanations of child mental health problems in Sierra Leone are commonly spiritual or supernatural in nature, and associated with help-seeking from traditional healers or religious institutions. There is a considerable amount of stigma related to mental disorders, which affects children, their caregivers and service providers, and may lead to discrimination and abuse. Child and Adolescent Mental Health (CAMH) care development in Sierra Leone should cater to the long-term structural effects of war-violence and an Ebola epidemic. Priorities for development include: (1) the strengthening of legal structures and the development of relevant policies that strengthen the health system and specifically include children and adolescents, (2) a clearer local distinction between children with psychiatric, neurological, developmental or psychosocial problems and subsequent channelling into appropriate services (3) supplementary CAMH training for a range of professionals working with children across various sectors, (4) specialist training in CAMH, (5) integration of CAMH care into primary health care, education and the social welfare system, (6) further research on local explanations of child mental disorders and the effect they have on the well-being of the child, and (7) a careful consideration of the role of religious healers as care

  4. Genetic diversity and evolutionary dynamics of Ebola virus in Sierra Leone.

    PubMed

    Tong, Yi-Gang; Shi, Wei-Feng; Liu, Di; Qian, Jun; Liang, Long; Bo, Xiao-Chen; Liu, Jun; Ren, Hong-Guang; Fan, Hang; Ni, Ming; Sun, Yang; Jin, Yuan; Teng, Yue; Li, Zhen; Kargbo, David; Dafae, Foday; Kanu, Alex; Chen, Cheng-Chao; Lan, Zhi-Heng; Jiang, Hui; Luo, Yang; Lu, Hui-Jun; Zhang, Xiao-Guang; Yang, Fan; Hu, Yi; Cao, Yu-Xi; Deng, Yong-Qiang; Su, Hao-Xiang; Sun, Yu; Liu, Wen-Sen; Wang, Zhuang; Wang, Cheng-Yu; Bu, Zhao-Yang; Guo, Zhen-Dong; Zhang, Liu-Bo; Nie, Wei-Min; Bai, Chang-Qing; Sun, Chun-Hua; An, Xiao-Ping; Xu, Pei-Song; Zhang, Xiang-Li-Lan; Huang, Yong; Mi, Zhi-Qiang; Yu, Dong; Yao, Hong-Wu; Feng, Yong; Xia, Zhi-Ping; Zheng, Xue-Xing; Yang, Song-Tao; Lu, Bing; Jiang, Jia-Fu; Kargbo, Brima; He, Fu-Chu; Gao, George F; Cao, Wu-Chun

    2015-08-06

    A novel Ebola virus (EBOV) first identified in March 2014 has infected more than 25,000 people in West Africa, resulting in more than 10,000 deaths. Preliminary analyses of genome sequences of 81 EBOV collected from March to June 2014 from Guinea and Sierra Leone suggest that the 2014 EBOV originated from an independent transmission event from its natural reservoir followed by sustained human-to-human infections. It has been reported that the EBOV genome variation might have an effect on the efficacy of sequence-based virus detection and candidate therapeutics. However, only limited viral information has been available since July 2014, when the outbreak entered a rapid growth phase. Here we describe 175 full-length EBOV genome sequences from five severely stricken districts in Sierra Leone from 28 September to 11 November 2014. We found that the 2014 EBOV has become more phylogenetically and genetically diverse from July to November 2014, characterized by the emergence of multiple novel lineages. The substitution rate for the 2014 EBOV was estimated to be 1.23 × 10(-3) substitutions per site per year (95% highest posterior density interval, 1.04 × 10(-3) to 1.41 × 10(-3) substitutions per site per year), approximating to that observed between previous EBOV outbreaks. The sharp increase in genetic diversity of the 2014 EBOV warrants extensive EBOV surveillance in Sierra Leone, Guinea and Liberia to better understand the viral evolution and transmission dynamics of the ongoing outbreak. These data will facilitate the international efforts to develop vaccines and therapeutics.

  5. Gross hematuria and urinary retention among men from a nationally representative survey in Sierra Leone.

    PubMed

    Patel, Hiten D; Kamara, Thaim B; Kushner, Adam L; Groen, Reinou S; Allaf, Mohamad E

    2014-06-01

    To estimate the prevalence of gross hematuria and urinary retention among men in Sierra Leone and report on barriers to care and associated disability. Gross hematuria and urinary retention are classic urologic complaints that require medical attention for significant underlying pathology, but their burden has not been quantified in a developing country. A cluster randomized, cross-sectional household survey was administered in Sierra Leone using the Surgeons OverSeas Assessment of Surgical need tool as a verbal head-to-toe examination. A total of 2 respondents in each of 25 households in 75 clusters were surveyed to assess surgical needs. Data on questions related to blood from the penis and the inability to urinate for men>12 years were included in the present analysis to determine the period and point prevalence of hematuria and urinary retention. From 3645 total respondents, 1054 (28.9%) were men>12 years included in the analysis. Period and point prevalence of gross hematuria were 21.8 per 1000 (95% confidence interval [CI] 13.0-30.7) and 12.3 per 1000 (95% CI 5.7-19.0), respectively, and for urinary retention, they were 19.9 per 1000 (95% CI 11.5-28.4) and 4.7 per 1000 (95% CI 0.5-8.9), respectively. Lack of financial resources was the major barrier to care. Disability assessment showed 19.1% were not able to work as a result of urinary retention, and 34.8% felt ashamed of their gross hematuria. The results provide a prevalence estimate of gross hematuria and urinary retention for men in Sierra Leone. Accessible medical and surgical care will be critical for early intervention and management. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Untreated head and neck surgical disease in Sierra Leone: a cross-sectional, countrywide survey.

    PubMed

    Van Buren, Nicholas C; Groen, Reinou S; Kushner, Adam L; Samai, Mohamed; Kamara, Thaim B; Ying, Jian; Meier, Jeremy D

    2014-10-01

    Demonstrate how the Surgeons OverSeas Assessment of Surgical Need (SOSAS) can be used to determine the burden of head and neck (H&N) surgical disease in developing countries and identify reasons for untreated disease. Cluster randomized, cross-sectional, countrywide survey. Sierra Leone. The survey was administered to 75 of 9671 enumeration areas in Sierra Leone between January 9 and February 3, 2012, with 25 households in each cluster randomly selected for the survey. A household representative and 2 randomly selected household members were interviewed. Need for surgical care was based on participants' responses to whether they had an H&N condition that they believed needed surgical care. Of 1875 households, data were analyzed for 1843 (98%), with 3645 total respondents. Seven hundred and one H&N surgical conditions were reported as occurring during the lifetime of the 3645 respondents (19.2%).The current prevalence of H&N conditions in need of a surgical consultation was 11.8%. No money (60.1%) was the most common reason respondents reported for not receiving medical care. A bivariate analysis demonstrated that age, village type, education, and type of condition may be predictors for seeking health care and/or receiving surgical care. These results show limited access for patients to be evaluated for a potential H&N surgical condition in Sierra Leone. The true incidence of untreated surgical disease is unknown as most respondents were not evaluated by a surgeon. This survey could be used in other countries as health care professionals assess surgical needs throughout the world. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

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

    PubMed

    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.

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

    PubMed

    Brolin Ribacke, Kim J; van Duinen, Alex J; Nordenstedt, Helena; Höijer, Jonas; Molnes, Ragnhild; Froseth, Torunn Wigum; Koroma, A P; Darj, Elisabeth; Bolkan, Håkon Angel; Ekström, AnnaMia

    2016-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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

  10. Technical efficiency of peripheral health units in Pujehun district of Sierra Leone: a DEA application

    PubMed Central

    Renner, Ade; Kirigia, Joses M; Zere, Eyob A; Barry, Saidou P; Kirigia, Doris G; Kamara, Clifford; Muthuri, Lenity HK

    2005-01-01

    Background The Data Envelopment Analysis (DEA) method has been fruitfully used in many countries in Asia, Europe and North America to shed light on the efficiency of health facilities and programmes. There is, however, a dearth of such studies in countries in sub-Saharan Africa. Since hospitals and health centres are important instruments in the efforts to scale up pro-poor cost-effective interventions aimed at achieving the United Nations Millennium Development Goals, decision-makers need to ensure that these health facilities provide efficient services. The objective of this study was to measure the technical efficiency (TE) and scale efficiency (SE) of a sample of public peripheral health units (PHUs) in Sierra Leone. Methods This study applied the Data Envelopment Analysis approach to investigate the TE and SE among a sample of 37 PHUs in Sierra Leone. Results Twenty-two (59%) of the 37 health units analysed were found to be technically inefficient, with an average score of 63% (standard deviation = 18%). On the other hand, 24 (65%) health units were found to be scale inefficient, with an average scale efficiency score of 72% (standard deviation = 17%). Conclusion It is concluded that with the existing high levels of pure technical and scale inefficiency, scaling up of interventions to achieve both global and regional targets such as the MDG and Abuja health targets becomes far-fetched. In a country with per capita expenditure on health of about US$7, and with only 30% of its population having access to health services, it is demonstrated that efficiency savings can significantly augment the government's initiatives to cater for the unmet health care needs of the population. Therefore, we strongly recommend that Sierra Leone and all other countries in the Region should institutionalise health facility efficiency monitoring at the Ministry of Health headquarter (MoH/HQ) and at each health district headquarter. PMID:16354299

  11. Clinical illness and outcomes in patients with Ebola in Sierra Leone.

    PubMed

    Schieffelin, John S; Shaffer, Jeffrey G; Goba, Augustine; Gbakie, Michael; Gire, Stephen K; Colubri, Andres; Sealfon, Rachel S G; Kanneh, Lansana; Moigboi, Alex; Momoh, Mambu; Fullah, Mohammed; Moses, Lina M; Brown, Bethany L; Andersen, Kristian G; Winnicki, Sarah; Schaffner, Stephen F; Park, Daniel J; Yozwiak, Nathan L; Jiang, Pan-Pan; Kargbo, David; Jalloh, Simbirie; Fonnie, Mbalu; Sinnah, Vandi; French, Issa; Kovoma, Alice; Kamara, Fatima K; Tucker, Veronica; Konuwa, Edwin; Sellu, Josephine; Mustapha, Ibrahim; Foday, Momoh; Yillah, Mohamed; Kanneh, Franklyn; Saffa, Sidiki; Massally, James L B; Boisen, Matt L; Branco, Luis M; Vandi, Mohamed A; Grant, Donald S; Happi, Christian; Gevao, Sahr M; Fletcher, Thomas E; Fowler, Robert A; Bausch, Daniel G; Sabeti, Pardis C; Khan, S Humarr; Garry, Robert F

    2014-11-27

    Limited clinical and laboratory data are available on patients with Ebola virus disease (EVD). The Kenema Government Hospital in Sierra Leone, which had an existing infrastructure for research regarding viral hemorrhagic fever, has received and cared for patients with EVD since the beginning of the outbreak in Sierra Leone in May 2014. We reviewed available epidemiologic, clinical, and laboratory records of patients in whom EVD was diagnosed between May 25 and June 18, 2014. We used quantitative reverse-transcriptase-polymerase-chain-reaction assays to assess the load of Ebola virus (EBOV, Zaire species) in a subgroup of patients. Of 106 patients in whom EVD was diagnosed, 87 had a known outcome, and 44 had detailed clinical information available. The incubation period was estimated to be 6 to 12 days, and the case fatality rate was 74%. Common findings at presentation included fever (in 89% of the patients), headache (in 80%), weakness (in 66%), dizziness (in 60%), diarrhea (in 51%), abdominal pain (in 40%), and vomiting (in 34%). Clinical and laboratory factors at presentation that were associated with a fatal outcome included fever, weakness, dizziness, diarrhea, and elevated levels of blood urea nitrogen, aspartate aminotransferase, and creatinine. Exploratory analyses indicated that patients under the age of 21 years had a lower case fatality rate than those over the age of 45 years (57% vs. 94%, P=0.03), and patients presenting with fewer than 100,000 EBOV copies per milliliter had a lower case fatality rate than those with 10 million EBOV copies per milliliter or more (33% vs. 94%, P=0.003). Bleeding occurred in only 1 patient. The incubation period and case fatality rate among patients with EVD in Sierra Leone are similar to those observed elsewhere in the 2014 outbreak and in previous outbreaks. Although bleeding was an infrequent finding, diarrhea and other gastrointestinal manifestations were common. (Funded by the National Institutes of Health and

  12. Medical Officers in Sierra Leone: Surgical Training Opportunities, Challenges and Aspirations.

    PubMed

    Wilks, Lucy; Leather, Andrew; George, Peter Matthew; Kamara, Thaim Bay

    2018-02-05

    The critical shortage of human resources for healthcare falls most heavily on sub-Saharan nations such as Sierra Leone, where such workforce deficits have grave impacts on its burden of surgical disease. An important aspect in retention and development of the workforce is training. This study focuses on postgraduate surgical training (formal and short course) and perceptions of opportunities, challenges and aspirations, in a country where more than half of surgical procedures are performed by medical officers. The study presents findings from 12 in-depth semi-structured interviews conducted with medical officers by the primary investigator in Sierra Leone between April and June 2017. Each interview was transcribed alongside an introspective reflexive journal to acknowledge and account for researcher biases. Two interviewees had accessed postgraduate surgical training and 10 (83%) had accessed short course surgically relevant training. The number of short courses accessed grew higher the more recently the medical officers had graduated. Supervision, short length and international standards were the most appreciated aspects of short training courses. Some medical officers perceived the formal postgraduate surgical training programme to be ill-equipped, doubting its credibility. This demotivated some from applying. Training is an essential aspect of developing an adequate surgical workforce. Faith must be restored in the capabilities of Sierra Leone's Ministry of Health and Sanitation to provide adequate and sustainable training. This study advocates for the use of short courses to restore this faith and the expansion of postgraduate surgical training to the districts through developing a regional teaching complex to provide short courses and eventually formal postgraduate training in the future. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  13. Traumatic Injuries in Developing Countries: Report from a Nationwide Cross-Sectional Survey of Sierra Leone

    PubMed Central

    Stewart, Kerry-Ann; Groen, Reinou S.; Kamara, Thaim B.; Farahzard, Mina; Samai, Mohamed; Yambasu, Sahr E.; Cassidy, Laura D.; Kushner, Adam L.; Wren, Sherry M.

    2014-01-01

    Objective Despite the tremendous disability and mortality caused by traumatic injuries worldwide, there is a relative dearth of information on the burden of injuries in developing countries. In an effort to document the surgical burden of disease in Sierra Leone, a nationwide survey was conducted utilizing the Surgeons OverSeas Assessment of Surgical Need (SOSAS) tool. Here, we report the injury data from this study with the aim to (1) provide an estimate of injury prevalence, (2) determine the mechanisms of injury, and (3) evaluate the degree of injury related deaths. Methods A population-based household survey was conducted in Sierra Leone in 2012. Participants were selected using a two-stage random sampling method, which generated a target population of 3750 participants across the 14 districts of Sierra Leone. Frequency distributions of mechanisms of injury based on age, sex, and urban versus rural residence were computed, and bivariate logistic regression models used to determine associations between sociodemographic factors and injury patterns. Results Data was analyzed from 1,843 households and 3,645 respondents, representing a response rate of 98.3%. Four hundred and fifty-two respondents (12.4%) reported at least one traumatic injury in the preceding year. Falls were the most common cause of non-fatal injuries, accounting for over 40% of injuries. The extremities were most commonly injured (55% of injuries) regardless of age or sex. Although motor vehicle related injuries were the 4th most common cause of injury overall, they were the leading cause of injury related deaths, accounting for almost 6% of fatal injuries. Conclusion This study provides baseline data on the burden of traumatic injuries in one of the world's poorest nations. In addition to injury prevention measures, immediate strategies to address current healthcare deficits are urgently needed in these resource poor areas. This report is an Original Article with Level I evidence. PMID:23325317

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

    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 <34.9), the probability of the latter fire burning into the previous fire area is extremely low. Analysis of fire severity data by 10-year periods revealed a fair degree of stability in the proportion of area burned among fire severity 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.

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

    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.

  16. Making up for lost snow: lessons from a warming Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Bales, R. C.

    2017-12-01

    Snowpack- and glacier-dependent river basins are home to over 1.2 billion people, one-sixth of the world's current population. These areas face severe challenges in a warmer climate, as declines in snow resources put more pressure on dams and groundwater. Closer to home, the seasonal snowpacks in California's Sierra Nevada provide water storage to both sustain productive forests and support the world's 6th largest economy. Rivers draining the Sierra supply the state's large cities, plus agricultural areas that provide nearly half of the nation's fruits and vegetables. Water storage is central to water security, especially given California's hot dry summers and high interannual variability in precipitation. On average seasonal snowpacks store about half as much water as do dams on Sierra rivers; and both the magnitude and duration of snowpack storage are decreasing. Precipitation amount and snow accumulation across the mountains in any given day, month or year remain uncertain. As historical index-statistical methods for hydrologic forecasts give way to tools based on mass and energy balances distributed across the landscape, opportunities are arising to broadly implement spatial measurements of snowpack storage and the equally important regolith-water storage. Advances in applying satellite and aircraft remote sensing, plus spatially distributed wireless-sensor networks, are filling this need. These same unprecedented data are driving process understanding to improve knowledge of snow-energy-forest interactions, snowmelt estimates, and hydrologic forecasts for hydropower, water supply, and flood control. Estimating the value of snowpacks and how they are changing provides a baseline for evaluating investments in restoration of headwater forests that will affect snowmelt runoff, and in providing replacement storage as snow declines. With California facing billions of dollars of green and grey infrastructure improvements, which must be compatible with the state

  17. DC-8 Airborne Laboratory in flight over snow-capped Sierra Nevada mountain range

    1998-02-25

    The DC-8 in flight near Lone Pine, Calif. In the foreground are the Sierra Nevada Mountains, covered with winter snow. In the distance are the White Mountains. The DC-8's fuselage is painted white with a dark blue stripe down the side. The wings are silver, while the engine pods are white. In this view of the airplane's right-hand side, only a few of its antennas are visible. The experimental payload can be as great as 30,000 pounds of equipment for gathering data of various sorts.

  18. LANDSAT-D investigations in snow hydrology. [Sierra Nevada Mountains, California

    NASA Technical Reports Server (NTRS)

    Dozier, J.

    1983-01-01

    Two tapes of the southern Sierra Nevada study area were received and the TM data are being registered to digital data. The spectral, spatial, temporal, and economic characteristics of data from LANDSAT 4 TM and MSS were compared with those of NOAA-r AVHRR data for snow cover mapping. An atmospheric radiative transfer model which accounts for both the zenith and aximuth variation in the radiative field is presented and its advantages are discussed. A Monte Carlo method for solving the atmospheric correction problem for an inhomogeneous surface is also considered.

  19. [Fertility of the Yanomami population of Sierra Parima (Amazonas Federal Territory, Venezuela)].

    PubMed

    Schkolnik, S

    1983-08-01

    This article presents information on the age structure and level of female fertility obtained on the basis of a sample of the Yanomami population (653 individuals) residing in the Venezuelan margin of Sierra Parima. The population observed is very young, over 50% are less than age 15, and the mean age is 18. The total fertility rate reaches 7.76 children/woman while the age distribution of rates show that fertility begins at a very early age and begins to decrease only after age 30. (author's modified)

  20. Navy Enhanced Sierra Mechanics (NESM): Toolbox for predicting Navy shock and damage

    SciT

    Moyer, Thomas; Stergiou, Jonathan; Reese, Garth

    Here, the US Navy is developing a new suite of computational mechanics tools (Navy Enhanced Sierra Mechanics) for the prediction of ship response, damage, and shock environments transmitted to vital systems during threat weapon encounters. NESM includes fully coupled Euler-Lagrange solvers tailored to ship shock/damage predictions. NESM is optimized to support high-performance computing architectures, providing the physics-based ship response/threat weapon damage predictions needed to support the design and assessment of highly survivable ships. NESM is being employed to support current Navy ship design and acquisition programs while being further developed for future Navy fleet needs.

  1. Maternal health, war, and religious tradition: authoritative knowledge in Pujehun District, Sierra Leone.

    PubMed

    Jambai, A; MacCormack, C

    1996-06-01

    In Sierra Leone constraints to ideal maternal health require a primary health care approach that includes collaboration with traditional midwives. They are authoritative figures embedded within local political structures and a powerful women's religion. The local causes of maternal risk are described, including civil war and refugee camp life. Traditional midwives provide vital services in the camp, are respected for their social status, and learn additional skills. Biomedical and traditional systems of authoritative knowledge, based on different kinds of legitimacy to heal, are in a complementary relationship.

  2. The Andean orogenic front at Sierra de Las Peñas-Las Higueras, Mendoza, Argentina

    NASA Astrophysics Data System (ADS)

    Costa, Carlos H.; Gardini, Carlos E.; Diederix, Hans; Cortés, José M.

    2000-07-01

    The Sierra de Las Peñas-Las Higueras (Mendoza Province, Argentina, 32°15'S-32°45'S) presents one of the clearest and most continuous exposures of the Quaternary thrust front of the Precordilleran fold-and-thrust belt. It is characterized by an east-verging thrust that breaks the surface and causes Neogene sedimentary rocks to override Quaternary alluvial conglomerates. Monoclinal folds and progressive unconformities are characteristic of deformation in the upper part of the alluvial cover, indicating synchronous development of sedimentation and thrusting during the Quaternary. South of this range, ongoing deformation is by gentle warping of the piedmont alluvial plain, hiding blind thrusts at depth.

  3. Knowledge and use of edible mushrooms in two municipalities of the Sierra Tarahumara, Chihuahua, Mexico.

    PubMed

    Quiñónez-Martínez, Miroslava; Ruan-Soto, Felipe; Aguilar-Moreno, Ivonne Estela; Garza-Ocañas, Fortunato; Lebgue-Keleng, Toutcha; Lavín-Murcio, Pablo Antonio; Enríquez-Anchondo, Irma Delia

    2014-09-17

    The Sierra Madre Occidental of Chihuahua in Northern Mexico is inhabited by indigenous Raramuris, mestizos, and other ethnic groups. The territory consists of canyons and ravines with pine, oak and pine-oak forests in the higher plateaus. A great diversity of potentially edible mushrooms is found in forests of the Municipalities of Bocoyna and Urique. Their residents are the only consumers of wild mushrooms in the Northern Mexico; they have a long tradition of collecting and eating these during the "rainy season." However, despite the wide diversity of edible mushrooms that grow in these areas, residents have a selective preference. This paper aims to record evidence of the knowledge and use of wild potentially edible mushroom species by inhabitants of towns in the Sierra Tarahumara of Chihuahua, Mexico. Using a semi-structured technique, we surveyed 197 habitants from seven locations in Urique, Bocoyna, and the Cusarare area from 2010 to 2012. Known fungi, local nomenclature, species consumed, preparation methods, appreciation of taste, forms of preservation, criteria for differentiating toxic and edible fungi, other uses, economic aspects, and traditional teaching were recorded. To identify the recognized species, photographic stimuli of 22 local edible species and two toxic species were used. The respondents reported preference for five species: Amanita rubescens, Agaricus campestris, Ustilago maydis, Hypomyces lactifluorum, and the Amanita caesarea complex. No apparent differences were found between ethnic groups in terms of preference, although mestizos used other species in Bocoyna (Boletus edulis and B. pinophilus). Some different uses of fungi are recognized by respondents, i.e. home decorations, medicine, as food in breeding rams, etc. The studied population shows a great appreciation towards five species, mainly the A. caesarea complex, and an apparent lack of knowledge of nearly 20 species which are used as food in other areas of Mexico. There are no

  4. 77 FR 47581 - Revisions to the California State Implementation Plan, Mojave Desert, Northern Sierra, Sacramento...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-09

    ...EPA is proposing to approve revisions to the Mojave Desert Air Quality Management District (MDAQMD), Northern Sierra Air Quality Management District (NSAQMD), Sacramento Metropolitan Air Quality Management District (SMAQMD) and San Diego County Air Pollution Control District (SDCAPCD) portions of the California State Implementation Plan (SIP). These revisions concern volatile organic compound (VOC) emissions from automotive parts and component, automobile refinishing, metal parts and products, and miscellaneous coating and refinishing operations. We are proposing to approve local rules to regulate these emission sources under the Clean Air Act as amended in 1990 (CAA or the Act).

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

    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.

  6. A new species of salamander (Caudata: Plethodontidae, Bolitoglossa) from Sierra Nevada de Mérida, Venezuela.

    PubMed

    García-Gutiérrez, Javier; Escalona, Moisés; Mora, Andrés; Díaz De Pascual, Amelia; Fermin, Gustavo

    2013-01-01

    In this article, a new species of salamander of the genus Bolitoglossa (Eladinea) from the cloud forest near La Mucuy in Sierra Nevada de Mérida, Venezuelan Andes, is described. Bolitoglossa mucuyensis sp. nov. differs from all Venezuelan salamanders, except B. orestes, by a larger SVL/TL ratio, and from La Culata salamander B. orestes by a reduced webbing extension of the front and hind limbs. Additionally, B. mucuyensis sp. nov. and B. orestes diverge 3.12% in terms of the nucleotide sequence of the 16S rRNA gene, as previously reported, and in 8.1% for the cytb gene as shown in this study.

  7. 78 FR 24471 - Endangered and Threatened Wildlife and Plants; Endangered Status for the Sierra Nevada Yellow...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ...We, the U.S. Fish and Wildlife Service, propose to list the Sierra Nevada yellow-legged frog and the northern distinct population segment (DPS) (populations that occur north of the Tehachapi Mountains) of the mountain yellow-legged frog as endangered species, and the Yosemite toad as a threatened species under the Endangered Species Act of 1973, as amended (Act). The effect of this regulation would be to add the species to the List of Endangered and Threatened Wildlife under the Act.

  8. Groundwater quality in the Yuba River and Bear River Watersheds, Sierra Nevada, California

    Fram, Miranda S.; Jasper, Monica; Taylor, Kimberly A.

    2017-09-27

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Program’s Priority Basin Project assesses the quality of groundwater resources used for drinking water supply and increases public access to groundwater-quality information. In the Yuba River and Bear River Watersheds of the Sierra Nevada, many rural households rely on private wells for their drinking water supplies. 

  9. The eastern front of the Sierra Nevada; prone to earthquakes and volcanic eruption

    Rinehart, C.D.; Smith, W.C.

    1981-01-01

    On Sunday morning, May 25, 1980, the weather at Mammoth Lakes, Calif., was sunny and brisk. Suddenly, just before 9:33 a.m, the world became a jarring, lurching, unstable place. Along the front of the Sierra Nevada, the muffled thunder of rockfalls and avalanches prolonged the confusion of sound and motion and added the spectacle of large, rising dust clouds. Three geysers, one 30 ft high, suddenly roared into the air at Hot Creek, although none survived more than a few hours. Some new boiling pools appeared, while many existing hot springs and pools became hotter and more active. 

  10. Navy Enhanced Sierra Mechanics (NESM): Toolbox for predicting Navy shock and damage

    DOE PAGES

    Moyer, Thomas; Stergiou, Jonathan; Reese, Garth; ...

    2016-05-25

    Here, the US Navy is developing a new suite of computational mechanics tools (Navy Enhanced Sierra Mechanics) for the prediction of ship response, damage, and shock environments transmitted to vital systems during threat weapon encounters. NESM includes fully coupled Euler-Lagrange solvers tailored to ship shock/damage predictions. NESM is optimized to support high-performance computing architectures, providing the physics-based ship response/threat weapon damage predictions needed to support the design and assessment of highly survivable ships. NESM is being employed to support current Navy ship design and acquisition programs while being further developed for future Navy fleet needs.

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

    Bermúdez-Lugo, Omayra; Menzie, William D.

    2015-01-01

    In response to the uncertainty surrounding the status of mineral projects in Guinea, Liberia, and Sierra Leone, the National Minerals Information Center compiled information on the distribution of mines, mineral facilities, and mineral projects under development in the three countries. This fact sheet provides information on the role that the mineral sector plays in their respective economies, on the operating status of mining projects through yearend 2014, and on the coordinated actions by mining companies to support governments and international relief organizations in their efforts to contain the EVD outbreak.

  12. Data on snow chemistry of the Cascade-Sierra Nevada Mountains

    Laird, L.B.; Taylor, Howard E.; Lombard, R.E.

    1986-01-01

    Snow chemistry data were measured for solutes found in snow core samples collected from the Cascade-Sierra Nevada Mountains from late February to mid-March 1983. The data are part of a study to assess geographic variations in atmospheric deposition in Washington, Oregon, and California. The constituents and properties include pH and concentrations of hydrogen ion, calcium, magnesium, sodium, potassium, chloride, sulfate, nitrate, fluoride, phosphate, ammonium, iron, aluminum, manganese, copper, cadmium, lead, and dissolved organic carbon. Concentrations of arsenic and bromide were below the detection limit. (USGS)

  13. Increasing elevation of fire in the Sierra Nevada and implications for forest change

    Schwartz, Mark W.; Butt, Nathalie; Dolanc, Christopher R.; Holguin, Andrew; Moritz, Max A.; North, Malcolm P.; Safford, Hugh D.; Stephenson, Nathan L.; Thorne, James H.; van Mantgem, Phillip J.

    2015-01-01

    Fire in high-elevation forest ecosystems can have severe impacts on forest structure, function and biodiversity. Using a 105-year data set, we found increasing elevation extent of fires in the Sierra Nevada, and pose five hypotheses to explain this pattern. Beyond the recognized pattern of increasing fire frequency in the Sierra Nevada since the late 20th century, we find that the upper elevation extent of those fires has also been increasing. Factors such as fire season climate and fuel build up are recognized potential drivers of changes in fire regimes. Patterns of warming climate and increasing stand density are consistent with both the direction and magnitude of increasing elevation of wildfire. Reduction in high elevation wildfire suppression and increasing ignition frequencies may also contribute to the observed pattern. Historical biases in fire reporting are recognized, but not likely to explain the observed patterns. The four plausible mechanistic hypotheses (changes in fire management, climate, fuels, ignitions) are not mutually exclusive, and likely have synergistic interactions that may explain the observed changes. Irrespective of mechanism, the observed pattern of increasing occurrence of fire in these subalpine forests may have significant impacts on their resilience to changing climatic conditions.

  14. Emplacement dynamics and hydrothermal alteration of the Atengo ignimbrite, southern Sierra Madre Occidental, northwestern Mexico

    NASA Astrophysics Data System (ADS)

    Agarwal, Amar; Alva-Valdivia, L. M.; Rivas-Sánchez, M. L.; Herrero-Bervera, E.; Urrutia-Fucugauchi, J.; Espejel-García, V.

    2017-12-01

    The Sierra Madre Occidental is a thick continental arc related to the subduction of the Farallon plate beneath North America resulting in a very intense and widespread Cretaceous to Cenozoic magmatic and tectonic activity. The 28 My old Atengo ignimbrite outcrops in the southern Sierra Madre Occidental, northwestern Mexico. From 12 sites that belong to various pyroclastic and lava flows emplaced during two pulses in the Oligocene (ca. 32-28 Ma) and Early Miocene (ca. 24-20 Ma), 97 rock specimens were drilled. The mineralogical and rock magnetic properties of the Atengo ignimbrite are compared with the surrounding volcanic rocks to identify the eruption mechanism, and with the El Castillo Ignimbrite, Veracruz, Mexico, to understand the depositional conditions. The comparisons reveal that the Atengo ignimbrite erupted from a single source, but less violently than the El Castillo ignimbrite, and cooled rapidly, inhibiting the formation of subhedral grains. The source of the Atengo Ignimbrite was a Plinian-type eruption, and the characteristic mineralogical and textural properties of each flow are related to different stages of the Plinian-type eruption. Further more, hydrothermal fluids were active during the last stages of volcanism, and caused moderate to intense alteration, especially in the ignimbrites, where high permeability aided the movement of hydrothermal fluids.

  15. Habitat preferences of butterflies in the Bumbuna Forest, Northern Sierra Leone.

    PubMed

    Sundufu, Abu James; Dumbuya, Rashida

    2008-01-01

    The habitat preferences of the butterfly fauna were studied in the Bumbuna Forest Reserve in northern Sierra Leone. The intact forest reserve and a secondary forest regrowth, disturbed as a result of slash-and-burn agriculture, were compared to savanna habitats. Of the 290 specimens collected, 195 butterfly species were included, of which significant proportion were Nymphalidae. Of the 147 forest species, 111 (75.5%) showed preferences for the forest habitats, while 70 (47.6%) and 34 (23.1%) preferred disturbed and savannah habitats, respectively. Numerically, a comparable proportion of savannah species were recorded in the 18 disturbed (73.9%) and 16 savannah habitats (63.2%). Accumulated species richness and diversity indices were lower in the disturbed habitats compared to the forest reserve, but lowest in the savanna habitats. However, a large proportion of forest species, especially those with either a more restricted geographic range or species for which no information on geographic distribution was available, were exclusively captured in the forest patches. The survey indicated the presence of a rich butterfly fauna, which should be systematically collected for further research and study in order to build a good taxonomic database for Sierra Leone.

  16. Atmospheric dry deposition on pines in the Eastern Brook Lake Watershed, Sierra Nevada, California

    NASA Astrophysics Data System (ADS)

    Bytnerowicz, Andrzej; Dawson, P. J.; Morrison, C. L.; Poe, M. P.

    Atmospheric dry deposition to branches of Pinus contorta and P. albicaulis was measured during summer 1987 in a sub-alpine zone at Eastern Brook Lake Watershed (EBLW), eastern Sierra Nevada, California. Results are presented as deposition fluxes of NO 3-, SO 42-, PO 43-, Cl -, F -, NH 4+, Ca 2+, Mg 2+, Na +, K +, Zn 2+, Fe 3+, Mn 2+, Pb 2+ and H +, and compared with other locations in California and elsewhere. Deposition fluxes of anions and cations to the pine branches were low, several times lower than the values determined near the Emerald Lake Watershed (ELW), another sub-alpine location in the western Sierra Nevada. The sums of deposition fluxes of the measured cations and anions to pine surfaces were similar, in contrast to the ELW location where the sums of cation fluxes were much higher than the sums of anion fluxes. A strong positive correlation between depositions of NO 3- and NH 4+, as well as SO 42- and Ca 2+, suggested that large portions of these ions might have originated from particulate NH 4NO 3 and CaSO 4 deposited on pine surfaces. An estimated total N dry deposition (surface deposition of NO 3- and NH 4+ and internal uptake of NO 2 and HNO 3) to the forested area of the EBLW was 29.54 eq ha -1 yr - (about 414 g H ha -1 yr -1).

  17. Health knowledge and health practices in Makeni, Sierra Leone: a community-based household survey.

    PubMed

    Abdelmalak, Mena J; Ahmed, Bilaal S; Mehta, Khanjan

    2016-05-01

    We characterize health knowledge and practices in urban and rural Makeni, Sierra Leone, drawing comparisons between areas served by community health workers (CHWs) with those that are not. We also inquire about causes of infant and maternal mortality and how they are understood in the local context. Our objective was to provide a baseline understanding of health knowledge and practices in Makeni during the implementation of a CHW program. We conducted 100 household interviews in Makeni City and rural villages in the surrounding area. We compared data between urban and rural areas to identify differences in health knowledge and practices. Our sample size covered 855 individuals. Insecticide treated bednet ownership was lower in urban settings compared to rural populations (58% vs 94%; p<.001). With regards to maternal mortality, most respondents indicated 'no clinic' (lack of clinical care or skipped antenatal care visits) as the primary cause (n=35), followed by bleeding (n=17), 'lack of blood' (anemia) (n=11) and 'will of God' (n=11). This initial survey of health knowledge and practices in rural and urban Makeni, Sierra Leone, highlights some simple opportunities for community health promotion, health education programming and behavioral interventions. Findings will inform future iterations of a CHW training module for community health education. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Ebola Virus Epidemiology, Transmission, and Evolution during Seven Months in Sierra Leone

    PubMed Central

    Park, Daniel J.; Dudas, Gytis; Wohl, Shirlee; Goba, Augustine; Whitmer, Shannon L.M.; Andersen, Kristian G.; Sealfon, Rachel S.; Ladner, Jason T.; Kugelman, Jeffrey R.; Matranga, Christian B.; Winnicki, Sarah M.; Qu, James; Gire, Stephen K.; Gladden-Young, Adrianne; Jalloh, Simbirie; Nosamiefan, Dolo; Yozwiak, Nathan L.; Moses, Lina M.; Jiang, Pan-Pan; Lin, Aaron E.; Schaffner, Stephen F.; Bird, Brian; Towner, Jonathan; Mamoh, Mambu; Gbakie, Michael; Kanneh, Lansana; Kargbo, David; Massally, James L.B.; Kamara, Fatima K.; Konuwa, Edwin; Sellu, Josephine; Jalloh, Abdul A.; Mustapha, Ibrahim; Foday, Momoh; Yillah, Mohamed; Erickson, Bobbie R.; Sealy, Tara; Blau, Dianna; Paddock, Christopher; Brault, Aaron; Amman, Brian; Basile, Jane; Bearden, Scott; Belser, Jessica; Bergeron, Eric; Campbell, Shelley; Chakrabarti, Ayan; Dodd, Kimberly; Flint, Mike; Gibbons, Aridth; Goodman, Christin; Klena, John; McMullan, Laura; Morgan, Laura; Russell, Brandy; Salzer, Johanna; Sanchez, Angela; Wang, David; Jungreis, Irwin; Tomkins-Tinch, Christopher; Kislyuk, Andrey; Lin, Michael F.; Chapman, Sinead; MacInnis, Bronwyn; Matthews, Ashley; Bochicchio, James; Hensley, Lisa E.; Kuhn, Jens H.; Nusbaum, Chad; Schieffelin, John S.; Birren, Bruce W.; Forget, Marc; Nichol, Stuart T.; Palacios, Gustavo F.; Ndiaye, Daouda; Happi, Christian; Gevao, Sahr M.; Vandi, Mohamed A.; Kargbo, Brima; Holmes, Edward C.; Bedford, Trevor; Gnirke, Andreas; Ströher, Ute; Rambaut, Andrew; Garry, Robert F.; Sabeti, Pardis C.

    2015-01-01

    Summary The 2013–2015 Ebola virus disease (EVD) epidemic is caused by the Makona variant of Ebola virus (EBOV). Early in the epidemic, genome sequencing provided insights into virus evolution and transmission and offered important information for outbreak response. Here, we analyze sequences from 232 patients sampled over 7 months in Sierra Leone, along with 86 previously released genomes from earlier in the epidemic. We confirm sustained human-to-human transmission within Sierra Leone and find no evidence for import or export of EBOV across national borders after its initial introduction. Using high-depth replicate sequencing, we observe both host-to-host transmission and recurrent emergence of intrahost genetic variants. We trace the increasing impact of purifying selection in suppressing the accumulation of nonsynonymous mutations over time. Finally, we note changes in the mucin-like domain of EBOV glycoprotein that merit further investigation. These findings clarify the movement of EBOV within the region and describe viral evolution during prolonged human-to-human transmission. PMID:26091036

  19. Dataset of Phenology of Mediterranean high-mountain meadows flora (Sierra Nevada, Spain).

    PubMed

    Pérez-Luque, Antonio Jesús; Sánchez-Rojas, Cristina Patricia; Zamora, Regino; Pérez-Pérez, Ramón; Bonet, Francisco Javier

    2015-01-01

    Sierra Nevada mountain range (southern Spain) hosts a high number of endemic plant species, being one of the most important biodiversity hotspots in the Mediterranean basin. The high-mountain meadow ecosystems (borreguiles) harbour a large number of endemic and threatened plant species. In this data paper, we describe a dataset of the flora inhabiting this threatened ecosystem in this Mediterranean mountain. The dataset includes occurrence data for flora collected in those ecosystems in two periods: 1988-1990 and 2009-2013. A total of 11002 records of occurrences belonging to 19 orders, 28 families 52 genera were collected. 73 taxa were recorded with 29 threatened taxa. We also included data of cover-abundance and phenology attributes for the records. The dataset is included in 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.

  20. Factors Underlying Ebola Virus Infection Among Health Workers, Kenema, Sierra Leone, 2014–2015

    PubMed Central

    Senga, Mikiko; Pringle, Kimberly; Ramsay, Andrew; Brett-Major, David M.; Fowler, Robert A.; French, Issa; Vandi, Mohamed; Sellu, Josephine; Pratt, Christian; Saidu, Josephine; Shindo, Nahoko; Bausch, Daniel G.

    2016-01-01

    Background. Ebola virus disease (EVD) in health workers (HWs) has been a major challenge during the 2014–2015 outbreak. We examined factors associated with Ebola virus exposure and mortality in HWs in Kenema District, Sierra Leone. Methods. We analyzed data from the Sierra Leone National Viral Hemorrhagic Fever Database, contact tracing records, Kenema Government Hospital (KGH) staff and Ebola Treatment Unit (ETU) rosters, and burial logs. Results. From May 2014 through January 2015, 600 cases of EVD originated in Kenema District, including 92 (15%) HWs, 66 (72%) of whom worked at KGH. Among KGH medical staff and international volunteers, 18 of 62 (29%) who worked in the ETU developed EVD, compared with 48 of 83 (58%) who worked elsewhere in the hospital. Thirteen percent of HWs with EVD reported contact with EVD patients, while 27% reported contact with other infected HWs. The number of HW EVD cases at KGH declined roughly 1 month after implementation of a new triage system at KGH and the opening of a second ETU within the district. The case fatality ratio for HWs and non-HWs with EVD was 69% and 74%, respectively. Conclusions. The cluster of HW EVD cases in Kenema District is one of the largest ever reported. Most HWs with EVD had potential virus exposure both inside and outside of hospitals. Prevention measures for HWs must address a spectrum of infection risks in both formal and informal care settings as well as in the community. PMID:27193749

  1. Transmission network of the 2014-2015 Ebola epidemic in Sierra Leone.

    PubMed

    Yang, Wan; Zhang, Wenyi; Kargbo, David; Yang, Ruifu; Chen, Yong; Chen, Zeliang; Kamara, Abdul; Kargbo, Brima; Kandula, Sasikiran; Karspeck, Alicia; Liu, Chao; Shaman, Jeffrey

    2015-11-06

    Understanding the growth and spatial expansion of (re)emerging infectious disease outbreaks, such as Ebola and avian influenza, is critical for the effective planning of control measures; however, such efforts are often compromised by data insufficiencies and observational errors. Here, we develop a spatial-temporal inference methodology using a modified network model in conjunction with the ensemble adjustment Kalman filter, a Bayesian inference method equipped to handle observational errors. The combined method is capable of revealing the spatial-temporal progression of infectious disease, while requiring only limited, readily compiled data. We use this method to reconstruct the transmission network of the 2014-2015 Ebola epidemic in Sierra Leone and identify source and sink regions. Our inference suggests that, in Sierra Leone, transmission within the network introduced Ebola to neighbouring districts and initiated self-sustaining local epidemics; two of the more populous and connected districts, Kenema and Port Loko, facilitated two independent transmission pathways. Epidemic intensity differed by district, was highly correlated with population size (r = 0.76, p = 0.0015) and a critical window of opportunity for containing local Ebola epidemics at the source (ca one month) existed. This novel methodology can be used to help identify and contain the spatial expansion of future (re)emerging infectious disease outbreaks. © 2015 The Author(s).

  2. Identifying spatio-temporal dynamics of Ebola in Sierra Leone using virus genomes

    PubMed Central

    Proctor, Joshua L.

    2017-01-01

    Containing the recent West African outbreak of Ebola virus (EBOV) required the deployment of substantial global resources. Despite recent progress in analysing and modelling EBOV epidemiological data, a complete characterization of the spatio-temporal spread of Ebola cases remains a challenge. In this work, we offer a novel perspective on the EBOV epidemic in Sierra Leone that uses individual virus genome sequences to inform population-level, spatial models. Calibrated to phylogenetic linkages of virus genomes, these spatial models provide unique insight into the disease mobility of EBOV in Sierra Leone without the need for human mobility data. Consistent with other investigations, our results show that the spread of EBOV during the beginning and middle portions of the epidemic strongly depended on the size of and distance between populations. Our phylodynamic analysis also revealed a change in model preference towards a spatial model with power-law characteristics in the latter portion of the epidemic, correlated with the timing of major intervention campaigns. More generally, we believe this framework, pairing molecular diagnostics with a dynamic model selection procedure, has the potential to be a powerful forecasting tool along with offering operationally relevant guidance for surveillance and sampling strategies during an epidemic. PMID:29187639

  3. Biostratigraphy and petrography of upper Paleozoic rocks of Sierra Las Pintas, northern Baja California

    NASA Astrophysics Data System (ADS)

    Navas-Parejo, Pilar; Lara-Peña, R. Aaron; Torres-Martínez, Miguel Angel; Martini, Michelangelo

    2018-07-01

    A transported crinoid fauna is herein described for the first time in the Paleozoic succession cropping out in the Sierra Las Pintas, northern Baja California, northwestern Mexico. The fossil association includes Heterostelechus texanus Moore and Jeffords, Preptopremnum laeve? Moore and Jeffords, and Mooreanteris perforatus Moore and Jeffords, which indicates a Middle Pennsylvanian-early Permian time-averaged age. The studied area corresponds with the northernmost outcrop of definitely late Paleozoic deep-water facies in northwestern Mexico and the southern United States. Petrographic analyses indicate that the studied metasandstones were primarily derived from high-grade metamorphic rocks and from a shallow-water platform environment dominated by crinoid meadows. These results allow the correlation of the studied metasedimentary rocks with the Carboniferous Rancho Nuevo Formation of the Sonora allochthon, which crops out in central Sonora. The Sonora allochthon includes an Early Ordovician-Late Pennsylvanian sedimentary succession that was deposited in the oceanic basin located south of the Laurentian craton. Therefore, upper Paleozoic metasedimentary rocks of the Sierra Las Pintas were deposited along the same continental margin of Laurentia as those rocks in the Sonora allochthon, and were mostly derived from metamorphic rocks of the continental craton and by the typical Carboniferous encrinites, which characterize the shallow-water rocks of central and northern Sonora.

  4. Treatment Seeking and Ebola Community Care Centers in Sierra Leone: A Qualitative Study.

    PubMed

    Carter, Simone E; O'Reilly, Marion; Frith-Powell, Jack; Umar Kargbo, Alpha; Byrne, Daniel; Niederberger, Eva

    2017-01-01

    Ebola Treatment Units were able to provide only 60% of necessary treatment beds in Sierra Leone. As a result, the Government of Sierra Leone decided to construct Community Care Centers. These were intended to increase treatment-seeking behavior and reduce the community-level spread of Ebola by facilitating access to care closer to communities. Through qualitative data collection in 3 districts, this study seeks to understand the perceived impact that proximity to such Centers had on treatment-seeking behavior. Feedback from community members and Community Health Volunteers indicates that proximity to treatment reduced fears, especially those arising from the use of ambulances, lack of familiarity with medical Centers, and loss of contact with family members taken for treatment. Participants report that having a Center close to their home enables them to walk to treatment and witness survivors being discharged. Living close to Centers also enables communities to be involved in their design and daily operation, helping to build trust in them as acceptable treatment facilities. Further research is required to understand the appropriate design, operation, and epidemiological impact of Centers. Further investigation should incorporate the effect of an outbreak's severity and the stage (duration) of the outbreak on potential acceptance of Centers.

  5. Evidence for Moho-lower crustal transition depth diking and rifting of the Sierra Nevada microplate

    NASA Astrophysics Data System (ADS)

    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 (<30 km thick). Here we isolate two very similar and unprecedented observations of Moho-lower crustal transition dike or fluid injection earthquake swarms under southern Sierra Valley (SV: 2011-2012) and North Lake Tahoe (LT: 2003-2004), California. These planar distributions of seismicity can be interpreted to define the end points, and cover 25% of the length, of an implied 56 km long 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).

  6. Marginalization of girl mothers during reintegration from armed groups in Sierra Leone.

    PubMed

    Burman, M E; McKay, S

    2007-12-01

    Although the widespread presence of girls who participate in fighting forces is increasingly recognized, they remain a highly marginalized group globally, receiving little attention either during or after armed conflict. This is especially true for "girl mothers," girls who return to communities with children born while members of fighting forces. The concept of marginalization (Hall et al. 1994) is used to examine what happens to girl soldiers, especially girl mothers, in the aftermath of armed conflict when they seek to reintegrate back into their communities. This analysis, as part of a larger study of reintegration of girl mothers, is based on field work with girls who were in fighting forces in northwest Sierra Leone, especially those who returned with children. The type and level of marginalization these girls experience is consistent with the conceptualization of marginalization; however, they lack voice and experience shame and vulnerability. Moreover, economics were fundamentally related to their marginalization. The girls' access to resources was significantly constrained because the area was heavily impacted by the war and because of widespread poverty throughout Sierra Leone. The findings raise important questions about marginalization of girls affected by war. Girls and girl mothers experience an extremely high level of marginalization; however, some aspects are not consistent with the original conceptualization of marginalization. Theory development in nursing needs to incorporate multiple voices, especially those of the very marginalized and be done in such a manner that benefits and empowers.

  7. Training peers to treat Ebola centre workers with anxiety and depression in Sierra Leone.

    PubMed

    Waterman, Samantha; Hunter, Elaine Catherine Margaret; Cole, Charles L; Evans, Lauren Jayne; Greenberg, Neil; Rubin, G James; Beck, Alison

    2018-03-01

    Following the 2014 Ebola virus disease (EVD) outbreak in West Africa, the UK Department for International Development funded South London and Maudsley National Health Service (NHS) to develop a psychological intervention that ex-Ebola Treatment Centre (ETC) staff could be trained to deliver to their peers to improve mental health in Sierra Leone. The two key aims were to assess the feasibility of training a national team to deliver a cognitive behavioural therapy (CBT)-based group intervention, and to evaluate the effectiveness of the overall intervention within this population. UK clinicians travelled to Sierra Leone to train a small team of ex-ETC staff in a three-phased CBT-based intervention. Standardised clinical measures, as well as bespoke measures, were applied with participants through the intervention to assess changes in mental health symptomology, and the effectiveness of the intervention. The results found improvements across all factors of mental health in the bespoke measure from phase 1 to phase 3. Additionally, the majority of standardised clinical measures showed improvements between phase 2 and the start of phase 3, and pre- and post-phase 3. Overall, the findings suggest that it is possible to train staff from ETCs to deliver effective CBT interventions to peers. The implications of these results are discussed, including suggestions for future research and clinical intervention implementation within this population. The limitations of this research are also addressed.

  8. Factors Underlying Ebola Virus Infection Among Health Workers, Kenema, Sierra Leone, 2014-2015.

    PubMed

    Senga, Mikiko; Pringle, Kimberly; Ramsay, Andrew; Brett-Major, David M; Fowler, Robert A; French, Issa; Vandi, Mohamed; Sellu, Josephine; Pratt, Christian; Saidu, Josephine; Shindo, Nahoko; Bausch, Daniel G

    2016-08-15

    Ebola virus disease (EVD) in health workers (HWs) has been a major challenge during the 2014-2015 outbreak. We examined factors associated with Ebola virus exposure and mortality in HWs in Kenema District, Sierra Leone. We analyzed data from the Sierra Leone National Viral Hemorrhagic Fever Database, contact tracing records, Kenema Government Hospital (KGH) staff and Ebola Treatment Unit (ETU) rosters, and burial logs. From May 2014 through January 2015, 600 cases of EVD originated in Kenema District, including 92 (15%) HWs, 66 (72%) of whom worked at KGH. Among KGH medical staff and international volunteers, 18 of 62 (29%) who worked in the ETU developed EVD, compared with 48 of 83 (58%) who worked elsewhere in the hospital. Thirteen percent of HWs with EVD reported contact with EVD patients, while 27% reported contact with other infected HWs. The number of HW EVD cases at KGH declined roughly 1 month after implementation of a new triage system at KGH and the opening of a second ETU within the district. The case fatality ratio for HWs and non-HWs with EVD was 69% and 74%, respectively. The cluster of HW EVD cases in Kenema District is one of the largest ever reported. Most HWs with EVD had potential virus exposure both inside and outside of hospitals. Prevention measures for HWs must address a spectrum of infection risks in both formal and informal care settings as well as in the community. © 2016 World Health Organization; licensee Oxford Journals.

  9. Control of Ebola hemorrhagic fever: vaccine development and our Ebola project in Sierra Leone.

    PubMed

    Watanabe, Tokiko; Kawaoka, Yoshihiro

    2016-01-01

    Since December 2013, West Africa has experienced the worst Ebola virus outbreak in recorded history. Of the 28,639 cases reported to the World Health Organization as of March 2016, nearly half (14,124) occurred in Sierra Leone. With a case fatality rate of approximately 40%, this outbreak has claimed the lives of 11,316 individuals. No FDA-approved vaccines or drugs are available to prevent or treat Ebola virus infection. Experimental vaccines and therapies are being developed; however, their safety and efficacy are still being evaluated. Therefore, there is an urgent need to develop control measures to prevent or limit future Ebola virus outbreaks.Previously, we developed a replication-defective Ebola virus that lacks the coding region for the essential viral transcription activator VP30 (Ebola ΔVP30 virus). Here, we evaluated the vaccine efficacy of Ebola ΔVP30 virus in a non-human primate model and describe our collaborative Ebola project in Sierra Leone.

  10. Snow Coverage Analysis Using ASTER over the Sierra Nevada Mountain Range

    NASA Astrophysics Data System (ADS)

    Ross, B.

    2017-12-01

    Snow has strong impacts on human behavior, state and local activities, and the economy. The Sierra Nevada snowpack is California's most important natural reservoir of water. Such snow is melting sooner and faster. A recent California drought study showed that there was a deficit of 1.5 million acre-feet of water in 2014 due to the fast melting rates. Scientists have been using the Moderate Resolution Imaging Spectrometer (MODIS) which is available at the spatial resolution of 500-meter, to analyze the changes in snow coverage. While such analysis provides us with the valuable information, it would be more beneficial to employ the imageries at a higher spatial resolution for snow studies. Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER), which acquires the high-resolution imageries ranging from 15-meter to 90-meter, has recently become freely available to the public. Our study utilized two scenes obtained from ASTER to investigate the changes in snow extent over the Sierra Nevada's mountain area for an 8-year period. These two scenes were collected on April 11, 2007 and April 16, 2015 covering the same geographic region. Normalized Difference Snow Index (NDSI) was adopted to delineate the snow coverage in each scene. Our study shows a substantial decrease of snow coverage in the studied geographic region by pixel count.

  11. Ozone distribution in remote ecologically vulnerable terrain of the southern Sierra Nevada, CA.

    PubMed

    Panek, Jeanne; Saah, David; Esperanza, Annie; Bytnerowicz, Andrzej; Fraczek, Witold; Cisneros, Ricardo

    2013-11-01

    Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more vulnerable to other agents of mortality, including insects, pathogens, climate change, and ultimately fire. Here we analyze three years of passive ozone monitor data from the southern Sierra Nevada and interpolate landscape-scale spatial and temporal patterns during the summer-through-fall high ozone concentration period. Segmentation analysis revealed three types of ozone exposure sub-regions: high, low, and variable. Consistently high ozone exposure regions are expected to be most vulnerable to forest mortality. One high exposure sub-region has been documented elsewhere as being further vulnerable to increased drought and fire potential. Identifying such hot-spots of forest vulnerability has utility for prioritizing management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Debris-Covered Glaciers in the Sierra Nevada, California, and Their Implications for Snowline Reconstructions

    Clark, D.H.; Clark, M.M.; Gillespie, A.R.

    1994-01-01

    Ice-walled melt ponds on the surfaces of active valley-floor rock glaciers and Matthes (Little Ice Age) moraines in the southern Sierra Nevada indicate that most of these landforms consist of glacier ice under thin (ca. 1 - 10 m) but continuous covers of rock-fall-generated debris. These debris blankets effectively insulate the underlying ice and greatly reduce rates of ablation relative to that of uncovered ice. Such insulation explains the observations that ice-cored rock glaciers in the Sierra, actually debris-covered glaciers, are apparently less sensitive to climatic warming and commonly advance to lower altitudes than do adjacent bare-ice glaciers. Accumulation-area ratios and toe-to-headwall-altitude ratios used to estimate equilibrium-line altitudes (ELAs) of former glaciers may therefore yield incorrect results for cirque glaciers subject to abundant rockfall. Inadvertent lumping of deposits from former debris-covered and bare-ice glaciers partially explains an apparently anomalous regional ELA gradient reported for the pre-Matthes Recess Peak Neoglacial advance. Distinguishing such deposits may be important to studies that rely on paleo-ELA estimates. Moreover, Matthes and Recess Peak ELA gradients along the crest evidently depend strongly on local orographic effects rather than latitudinal climatic trends, indicating that simple linear projections and regional climatic interpretations of ELA gradients of small glaciers may be unreliable.

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

    SciT

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.

    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 atmore » 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.« less

  14. Habitat Preferences of Butterflies in the Bumbuna Forest, Northern Sierra Leone

    PubMed Central

    Sundufu, Abu James; Dumbuya, Rashida

    2008-01-01

    The habitat preferences of the butterfly fauna were studied in the Bumbuna Forest Reserve in northern Sierra Leone. The intact forest reserve and a secondary forest regrowth, disturbed as a result of slash-and-burn agriculture, were compared to savanna habitats. Of the 290 specimens collected, 195 butterfly species were included, of which significant proportion were Nymphalidae. Of the 147 forest species, 111 (75.5%) showed preferences for the forest habitats, while 70 (47.6%) and 34 (23.1%) preferred disturbed and savannah habitats, respectively. Numerically, a comparable proportion of savannah species were recorded in the 18 disturbed (73.9%) and 16 savannah habitats (63.2%). Accumulated species richness and diversity indices were lower in the disturbed habitats compared to the forest reserve, but lowest in the savanna habitats. However, a large proportion of forest species, especially those with either a more restricted geographic range or species for which no information on geographic distribution was available, were exclusively captured in the forest patches. The survey indicated the presence of a rich butterfly fauna, which should be systematically collected for further research and study in order to build a good taxonomic database for Sierra Leone. PMID:20302525

  15. Associations of stream health to altered flow and water temperature in the Sierra Nevada, California

    Carlisle, Daren M.; S. Mark Nelson,; May, Jason

    2016-01-01

    Alteration of streamflow and thermal conditions may adversely affect lotic invertebrate communities, but few studies have assessed these phenomena using indicators that control for the potentially confounding influence of natural variability. We designed a study to assess how flow and thermal alteration influence stream health – as indicated by the condition of invertebrate communities. We studied thirty streams in the Sierra Nevada, California, that span a wide range of hydrologic modification due to storage reservoirs and hydroelectric diversions. Daily water temperature and streamflows were monitored, and basic chemistry and habitat conditions were characterized when invertebrate communities were sampled. Streamflow alteration, thermal alteration, and invertebrate condition were quantified by predicting site-specific natural expectations using statistical models developed using data from regional reference sites. Monthly flows were typically depleted (relative to natural expectations) during fall, winter, and spring. Most hydrologically altered sites experienced cooled thermal conditions in summer, with mean daily temperatures as much 12 °C below natural expectations. The most influential predictor of invertebrate community condition was the degree of alteration of March flows, which suggests that there are key interactions between hydrological and biological processes during this month in Sierra Nevada streams. Thermal alteration was also an important predictor – particularly at sites with the most severe hydrological alteration.

  16. Dataset of Phenology of Mediterranean high-mountain meadows flora (Sierra Nevada, Spain)

    PubMed Central

    Pérez-Luque, Antonio Jesús; Sánchez-Rojas, Cristina Patricia; Zamora, Regino; Pérez-Pérez, Ramón; Bonet, Francisco Javier

    2015-01-01

    Abstract Sierra Nevada mountain range (southern Spain) hosts a high number of endemic plant species, being one of the most important biodiversity hotspots in the Mediterranean basin. The high-mountain meadow ecosystems (borreguiles) harbour a large number of endemic and threatened plant species. In this data paper, we describe a dataset of the flora inhabiting this threatened ecosystem in this Mediterranean mountain. The dataset includes occurrence data for flora collected in those ecosystems in two periods: 1988–1990 and 2009–2013. A total of 11002 records of occurrences belonging to 19 orders, 28 families 52 genera were collected. 73 taxa were recorded with 29 threatened taxa. We also included data of cover-abundance and phenology attributes for the records. The dataset is included in 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:25878552

  17. Controls on drainage divide migration in the northern Sierras Pampeanas assessed through morphometric indicators

    NASA Astrophysics Data System (ADS)

    Seagren, E. G.; Schoenbohm, L. M.

    2017-12-01

    Drainage reorganization, primarily through progressive divide migration leading to discrete stream captures, is increasingly recognized as a common phenomenon during mountain-building events. This drainage rearrangement reflects complex interactions between tectonics, climate, and lithology, and can fundamentally change erosion and sedimentation patterns; therefore, determining the spatial extent and potential controls of divide migration is vital to understanding the topographic evolution of orogenic landscapes. Both geomorphic and morphometric evidence can be used to identify such drainage reorganization. The northern Sierras Pampeanas is an ideal location in which to study divide migration as limited glaciation and low out-of-channel erosion rates preserve evidence of reorganization. Additionally, several ranges in the region, such as Sierra de las Planchadas, exhibit geomorphic evidence of drainage rearrangement, including wind gaps and hairpin turns. Using ArcGIS, LSDTopoTools, and TopoToolbox, we conducted a systematic analysis of the spatial distribution of three morphometric indicators of divide migration: χ, Mx, and local headwater relief. Local `hotspots' undergoing drainage divide migration were identified using spatial autocorrelation and clustering methods - Gi* and Moran's I. Using spatial regression analysis, we assessed the potential controls of lithology, modern TRMM precipitation rates, and tectonics over divide migration. Preliminary results suggest broad westward migration of main drainage divides, following both the orographic precipitation gradient and regional slope.

  18. Chemical composition of snow in the east-central Sierra Nevada

    SciT

    Brown, J.C.; Skau, C.M.

    1975-01-01

    The chemical quality of snowfall in the east-central Sierra Nevada mountains was measured four times at twenty-six sampling points during the period January to April 1975. Mean concentrations (ppM) and total production (lbs/mi2) of eleven major chemical constituents are reported. These values were related to six sampling site characteristics, using simple correlation techniques, to determine the factors which influence the chemical variability of snowfall over this area. Chemical concentrations in the snow here are, apparently, much lower than for precipitation reported in other parts of the country. Nitrogen and phosphorus concentrations, however, are similar to those found in small, easternmore » Sierra streams. The chemical concentrations in snowfall exhibit little variability between sampling sites. This suggests atmospheric concentrations of these constituents are relatively uniform over the area, with localized human activity having, apparently, little influence. The dominant factor causing variation of winter production values (lbs/mi2) between sites is simply the amount of precipitation.« less

  19. Traumatic injuries in developing countries: report from a nationwide cross-sectional survey of Sierra Leone.

    PubMed

    Stewart, Kerry-Ann A; Groen, Reinou S; Kamara, Thaim B; Farahzad, Mina M; Samai, Mohamed; Cassidy, Laura D; Kushner, Adam L; Wren, Sherry M

    2013-05-01

    To use a nationwide household survey tool to provide an estimate of injury prevalence, mechanisms of traumatic injuries, and number of injury-related deaths in a low-income country. A randomized, cross-sectional nationwide survey using the Surgeons OverSeas Assessment of Surgical Need tool was conducted in 2012. Sierra Leone, Africa. Three thousand seven hundred fifty randomly selected participants throughout Sierra Leone. Mechanisms of injury based on age, sex, anatomic location, cause, and sociodemographic factors as well as mechanisms of injury-related deaths in the previous year were the primary outcome measures. Data were collected and analyzed from 1843 households and 3645 respondents (98% response rate). Four hundred fifty-two respondents (12%) reported at least 1 traumatic injury in the preceding year. Falls were the most common cause of nonfatal injuries (40%). The extremities were the most common injury site regardless of age or sex. Traffic injuries were the leading cause of injury-related deaths (32% of fatal injuries). This study provides baseline data on the mechanisms of traumatic injuries as well as the sociodemographic factors affecting injury prevalence in one of the world's poorest nations. It is anticipated that these data will provide an impetus for further studies to determine injury severity, associated disability, and barriers to accessing care in these resource-poor areas.

  20. Fluid mixing and ore deposition during the geodynamic evolution of the Sierra Almagrera (Betics, Spain)

    NASA Astrophysics Data System (ADS)

    Dyja, Vanessa; Tarantola, Alexandre; Hibsch, Christian; Boiron, Marie-Christine; Cathelineau, Michel

    2013-04-01

    Marine and continental intramountaineous basins developed during the Neogene orographic evolution of the Betico-rifan orogenic wedge, as well as the related uplifted ranges within the Sierra Almagrera Metamorphic Core Complexes (MCC). The NNE-SSW striking trans-Alboran transcurrent fault system crosscuts the MCC post-dating the extensional exhumation stages recorded in the metamorphic fabric. Iron ores (± Pb, Cu, Zn) are encountered either as stratabound ore deposits in the Neogene basins or as vein networks crosscutting the metamorphic fabric of graphitic phyllites from the Sierra Almagrera. These Late Miocene ore deposits are related to the activity of the N-S striking Palomares fault segment of the Trans-Alboran fault system. Three sets of quartz veins (Vα, Vαβ and Vβ) and one set of mineralized vein (Vγ, siderite, barite) are distinguished. The Vα and Vαβ respectively are totally or partially transposed into the foliation. The Vβ and Vγ veins are discordant to the foliation. The problem addressed in this study concerns the nature of the fluids involved in the metal deposits and their relationships with the main reservoir fluids, e.g. the deep metamorphic fluids, the basinal fluids, and eventually the recharge meteoric fluids. This study focuses thus on the evolution of the fluids at different stages of ductile-brittle exhumation of the metamorphic ranges (Sierras) and their role during the exhumation and later on in relation with the hydrothermalism and metal deposition at a regional scale. Paleofluids were studied as inclusions in quartz, siderite and barite from veins by microthermometry and Raman spectroscopy, and a stable isotope study is in progress. Earliest fluids recorded in (Vαβ) quartz veins are H2O- NaCl + CaCl2 (17 wt. %) - (traces of CO2, CH4, N2) metamorphic brines trapped at the ductile brittle transition at a minimum trapping temperatures (Th) of 340 °C. Older metamorphic fluids in (Vα) veins were lost during the complete

  1. Modeling the influence of precipitation and nitrogen deposition on forest understory fuel connectivity in Sierra Nevada mixed-conifer forest

    M. Hurteau; M. North; T. Foines

    2009-01-01

    Climate change models for California’s Sierra Nevada predict greater inter-annual variability in precipitation over the next 50 years. These increases in precipitation variability coupled with increases in nitrogen deposition fromfossil fuel consumption are likely to result in increased productivity levels and significant increases in...

  2. Climate, rain shadow, and human-use influences on fire regimes in the eastern Sierra Nevada, California, USA

    M.P. North; K.M. van de Water; S.L. Stephens; B.M. Collins

    2009-01-01

    There have been few fire history studies of eastern Sierra Nevada forests in California, USA, where a steep elevation gradient, rain shadow conditions, and forest stand isolation may produce different fire regimes than those found on the range’s western slope. We investigated historic fire regimes and potential climate influences on four forest types ranging in...

  3. Impacts of rodenticide and insecticide toxicants from marijuana cultivation on fisher survival rates in the Sierra National Forest, California.

    Craig Thompson; Kathryn Purcell

    2013-01-01

    Secondary exposure of wildlife to pesticides has been well documented, yet exposure is typically associated with agricultural or wildland-urban interface areas. Wildlife in undeveloped areas is generally presumed free from risk. In 2009, a male fisher was found dead in the Sierra National Forest and subsequent necropsy revealed that the animal died of acute rodenticide...

  4. Content of chemical elements in tree rings of lodgepole pine and whitebark pine from a subalpine Sierra Nevada forest

    David L. Peterson; Darren R. Anderson

    1990-01-01

    The wood of lodgepole pines and whitebark pines from a high elevation site in the east central Sierra Nevada of California was analyzed for chemical content to determine whether there were any temporal patterns of chemical distribution in tree rings. Cores were taken from 10 trees of each species and divided into 5-year increments for chemical analysis. Correlation...

  5. Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California

    R. Cisneros; A. Bytnerowicz; D. Schweizer; S. Zhong; S. Traina; D.H. Bennett

    2010-01-01

    Two-week average concentrations of ozone (O3), nitric acid vapor (HNO3) and ammonia (NH3) 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...

  6. Species Composition and Habitat Associations of Benthic Algal Assemblages in Headwater Streams of the Sierra Nevada, California

    Larry R. Brown; Jason T. May; Carolyn T. Hunsaker

    2008-01-01

    Despite their trophic importance and potential importance as bioindicators of stream condition, benthic algae have not been well studied in California. In particular there are few studies from small streams in the Sierra Nevada. The objective of this study was to determine the standing crop of chlorophyll-a and benthic algal species assemblages...

  7. PAST CLIMATES, FORESTS, AND DISTURBANCES OF THE SIERRA NEVADA, CALIFORNIA: UNDERSTANDING THE PAST TO MANAGE FOR THE FUTURE

    William F. Laudenslayer; Carl N. Skinner

    1995-01-01

    The forests of the Sierra Nevada have been altered for millennia by climate, natural disturbances, and more recently by the activities of humans. Management of these forests and their resources as ecosystems to meet diverse objectives, requires an understanding of the conditions under which existing forests developed and how they have changed through time. Recently...

  8. 78 FR 53477 - Notice of Relocation of the Bureau of Land Management's San Pedro Project Office in Sierra Vista, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLAZG02000.L143000000.EQ0000.TAS:14X1109.241A] Notice of Relocation of the Bureau of Land Management's San Pedro Project Office in Sierra Vista... relocation of the Bureau of Land Management's (BLM) San Pedro Project Office (SPPO), temporary closure of the...

  9. Movements and habitat use of Yosemite toads (Anaxyrus (formerly Bufo) canorus) in the Sierra National Forest, California

    Christina T. Liang

    2013-01-01

    The Yosemite Toad (Anaxyrus (Bufo) canorus) is a high-elevation species endemic to the central Sierra Nevada mountain range in California whose populations are in decline. There is limited information on their terrestrial movement and habitat use, which impairs our understanding of the ecology and habitat...

  10. Mastication and prescribed fire impacts on fuels in a 25-year old ponderosa pine plantation, southern Sierra Nevada

    Alicia L. Reiner; Nicole M. Vaillant; JoAnn Fites-Kaufman; Scott N. Dailey

    2009-01-01

    Due to increases in tree density and hazardous fuel loading in Sierra Nevadan forests, land management is focusing on fuel reduction treatments to moderate the risk of catastrophic fires. Fuel treatments involving mechanical and prescribed fire methods can reduce surface as well as canopy fuel loads. Mastication is a mechanical method which shreds smaller trees and...

  11. Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California

    Haiganoush K. Preisler; Shiyuan (Sharon) Zhong; Annie Esperanza; Timothy J. Brown; Andrzej Bytnerowicz; Leland Tarnay

    2010-01-01

    Data from four continuous ozone and weather monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an...

  12. A dendrochronology based fire history of Jeffry pine-mixed conifer forests in the Sierra San Pedro Martir, Mexico

    Scott L. Stephens; Carl N. Skinner; Samantha J. Gill

    2003-01-01

    Conifer forests in northwestern Mexico have not experienced systematic fire suppression or logging, making them unique in western North America. Fire regimes of Pinus jeffreyi Grev. & Balf. mixed conifer forests in the Sierra San Pedro Martir, Baja California, Mexico, were determined by identifying 105 fire dates from 1034 fire scars in 105 specimens. Fires were...

  13. Fluctuating populations of house wrens and Bewick's wrens in foothills of the western Sierra Nevada of California

    Jared Verner; Kathryn L. Purcell

    1999-01-01

    In foothills of the western Sierra Nevada, 31 km east of Madera, California, we studied whether Bewick's Wrens (Thryomanes bewickii) tend to be excluded from an area occupied by House Wrens (Troglodytes aedon) as reported in several studies in the eastern United States. Neither point counts from 1985 to 1997 nor spot mapping from 1989 to 1993 suggests any...

  14. Reproduction, abundance, and population growth for a fisher (Pekania pennanti) population in the Sierra National Forest, California

    Rick A. Sweitzer; Viorel D. Popescu; Reginald H. Barrett; Kathryn L. Purcell; Craig M. Thompson

    2015-01-01

    In the west coast region of the United States, fishers (Pekania pennanti) exist in 2 remnant populations—1 in northern California and 1 in the southern Sierra Nevada, California—and 3 reintroduced populations (western Washington, southern Oregon, and northeastern California). The West Coast Distinct Population Segment of fishers encompassing all of...

  15. Soil nutrients and microbial activity after early and late season prescribed burns in a Sierra Nevada mixed conifer forest

    Sarah T. Hamman; Ingrid C. Burke; Eric E. Knapp

    2008-01-01

    Restoring the natural fire regime to forested systems that have experienced fire exclusion throughout the past century can be a challenge due to the heavy fuel loading conditions. Fire is being re-introduced to mixed conifer forests in the Sierra Nevada through both early season and late season prescribed burns, even though most fires historically occurred in the late...

  16. Effects on nonnative fishes on wilderness lake ecosystems in the Sierra Nevada and recommendations for reducing impacts

    R. A. Knapp; Kathleen R. Matthews

    2000-01-01

    Wilderness areas of the Sierra Nevada, California contain thousands of lakes and ponds, nearly all of which were historically fishless. After more than a century of fish stocking, introduced trout are now present in up to 80% of larger lakes. These nonnative fishes have had profound impacts on native fishes, amphibians, and invertebrates. Several of these native...

  17. Satellite Image Mapping of Tree Mortality in the Sierra Nevada Region of California from 2013 to 2016

    NASA Technical Reports Server (NTRS)

    Potter, Christopher S.

    2017-01-01

    Extreme drought from 2013 to 2015 has been linked to extensive tree dieback in the Sierra-Nevada region of California. Landsat satellite imagery was analysed for the region from Lake Tahoe to the southern Sequoia National Forest with the objective of understanding the patterns of tree mortality in the years of 2013 to 2015 and into the near-normal precipitation year of 2016. The main mapping results for Landsat moisture index differences from year-to-year showed that the highest coverage of tree dieback was located in the Sierra and Sequoia National Forests, at four to five times greater area each year than within any other National Park or National Forest unit. Since 2013, over 50% of the Sierra Nevada forest dieback area was detected in the mid elevation zone of 1000-2000 m. The total area of tree mortality in the lower elevation zone of 500-1000 m did not grow notably from 2015 to 2016. Within the largest California river drainages in the Sierra region, new tree mortality in 2015 was detected mainly below 1200 m elevation, whereas new tree mortality in 2016 was detected mainly at higher elevations, up to about 2200 m. In three out of the four years studied, results showed that about 60% of all new tree mortality areas were located on north-facing hill slopes.

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

    ERIC Educational Resources Information Center

    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…

  19. Fire and fire surrogate study in the Sierra Nevada: evaluating restoration treatments at Blodgett Forest and Sequoia National Park

    Eric E. Knapp; Scott L. Stephens; James D. McIver; Jason J. Moghaddas; Jon E. Keeley

    2004-01-01

    Management practices have altered both the structure and function of forests throughout the United States. Some of the most dramatic changes have resulted from fire exclusion, especially in forests that historically experienced relatively frequent, low- to moderate-intensity fire regimes. In the Sierra Nevada, fire exclusion is believed to have resulted in widespread...

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

    ERIC Educational Resources Information Center

    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…

  1. Confronting the implications of wicked problems: changes needed in Sierra Nevada National Forest planning and problem solving

    Hal Salwasser

    2004-01-01

    Thirty years ago, the fate of migratory deer in the Sierra Nevada was thought to be the major forest wildlife issue. Ten years later, agencies were building the California Wildlife Habitat Relationships System to allow managers to integrate all terrestrial vertebrates with timber management in comprehensive National Forest planning. Another ten years after that, Tom...

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

    ERIC Educational Resources Information Center

    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…

  3. Multi-scale evaluation of the environmental controls on burn probability in a southern Sierra Nevada landscape

    Sean A. Parks; Marc-Andre Parisien; Carol Miller

    2011-01-01

    We examined the scale-dependent relationship between spatial fire likelihood or burn probability (BP) and some key environmental controls in the southern Sierra Nevada, California, USA. Continuous BP estimates were generated using a fire simulation model. The correspondence between BP (dependent variable) and elevation, ignition density, fuels and aspect was evaluated...

  4. Characteristics of nest trees and nest sites of California spotted owls in coniferous forests of the southern Sierra Nevada

    George N. Steger; Thomas E. Munton; Kenneth D. Johnson; Gary E. Eberlein

    1997-01-01

    We described 86 nest sites of California spotted owl (Sh-ix occidentalis occrdentalzs) and tested for differences in vegetation structure at nest locations rn conifer-dominated stands in 2 study areas, the Sierra National Forest (SNF) and Sequoia and Kings Canyon National Parks (SNP), California. All nests were between 1061 and 2414 m in elevation, 52 were side-cavity...

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

    ERIC Educational Resources Information Center

    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…

  6. 78 FR 72926 - Bald and Golden Eagles; Migratory Birds; Phase I Development of the Chokecherry-Sierra Madre Wind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-04

    ... which this notice primarily pertains, would consist of approximately 500 wind turbines, a haul road, a... development for CCSM Phase II, which will consist of about 500 additional wind turbines (roughly 1500 MW), at...-FXMB12310600000] Bald and Golden Eagles; Migratory Birds; Phase I Development of the Chokecherry-Sierra Madre Wind...

  7. Rock glaciers and related periglacial landforms in the Sierra Nevada, CA, USA; inventory, distribution and climatic relationships

    Constance I. Millar; Robert D. Westfall

    2008-01-01

    Rock glaciers and related periglacial rock-ice features (RIFs) are abundant yet overlooked landforms in the Sierra Nevada, California, where they occur in diverse forms. We mapped 421 RIFs from field surveys, and grouped these into six classes based on morphology and location. These categories comprise a greater range of frozen-ground features than are commonly...

  8. A tool and index to assess surgical capacity in low income countries: an initial implementation in Sierra Leone.

    PubMed

    Groen, Reinou S; Kamara, Thaim B; Dixon-Cole, Richmond; Kwon, Steven; Kingham, T Peter; Kushner, Adam L

    2012-08-01

    A first step toward improving surgical care in many low and middle income countries is to document the need. To facilitate the collection and analysis of surgical capacity data and measure changes over time, Surgeons OverSeas (SOS) developed a tool and index based on personnel, infrastructure, procedures, equipment, and supplies (PIPES). A follow-up assessment of 10 government hospitals in Sierra Leone was completed 42 months after an initial survey in 2008 using the PIPES tool. An index based on number of operating rooms, personnel, infrastructure, procedures, equipment, and supplies was calculated. An index was also calculated, using the 2008 data for comparison. Most hospitals demonstrated an increased index that correlated with site visits that verified improved conditions. Connaught Hospital in Sierra Leone had the highest score (9.2), consistent with its being the best equipped and staffed Ministry of Health and Sanitation facility. Makeni District Hospital had the greatest increase, from 3.8 to 7.5, consistent with a newly constructed facility. The PIPES tool was easily administered at hospitals in Sierra Leone and an index was found useful. Surgical capacity in Sierra Leone improved between 2008 and 2011, as demonstrated by an increase in the overall PIPES indices.

  9. Rural-Urban Migration in Sierra Leone: Determinants and Policy Implications. African Rural Economy Paper No. 13.

    ERIC Educational Resources Information Center

    Byerlee, Derek; And Others

    Study objectives were to: increase the understanding of rural to urban migration processes in Africa and Sierra Leone; develop and test a theoretical schema and survey methodology for migration research; and evaluate the effects of policy on migration. The migration survey was conducted in rural areas, urban areas, and again in the rural areas…

  10. Assessment of post-fire forest structural diversity using neighborhood parameter in the Sierra Madre Oriental, Mexico

    Diana Yemilet Avila Flores; Marco Aurelio González Tagle; Javier Jiménez Pérez; Oscar Aguirre Calderón; Eduardo Treviño Garza

    2013-01-01

    The objective of this research was to characterize the spatial structure patterns of a Pinus hartwegii forest in the Sierra Madre Oriental, affected by a fire in 1998. Sampling was stratified by fire severity. A total of three fire severity classes (low, medium and high) were defined. Three sample plots of 40m x 40m were established for each...

  11. Concerning KAr dating of a basalt flow from the Tahoe-Tioga interglaciation, Sawmill Canyon, southeastern Sierra Nevada, California

    Dalrymple, G.B.; Burke, R.M.; Birkeland, P.W.

    1982-01-01

    New KAr ages for a basalt flow interbedded with Tahoe and Tioga tills in Sawmill Canyon, southeastern Sierra Nevada, slightly refine previously published ages for the flow and provide an estimate of 53,000 ± 44,000 yr for the Tahoe-Tioga interglaciation.

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

    DTIC Science & Technology

    2010-05-01

    such that the dechirped signal is at an intermediate frequency. Feedthrough rejection is done by a surface acoustic wave (SAW) filter with its first...Fig. 3. NASA SIERRA UAS 3-View and Specifications • Up-looking and down-looking shortwave spectrometers. • Down-looking temperature sensors ( pyrometers

  13. Ozone injury responses of ponderosa and Jeffrey pine in the Sierra Nevada and San Bernardino Mountains in California

    Paul Miller; Raleigh Guthrey; Susan Schilling; John Carroll

    1998-01-01

    Ozone injury was monitored on foliage of ponderosa (Pinus ponderosa Dougl. ex Laws.) and Jeffrey (Pinus jeffreyi Grev. & Balf.) pines at 11 locations in the Sierra Nevada and 1 site in the San Bernardino Mountains of southern California. Ozone injury on all age cohorts of needles on about 1,600 trees was surveyed annually from...

  14. Site index curves for young-growth California white fir on the western slopes of the Sierra Nevada

    K. Leroy Dolph

    1987-01-01

    Site index curves for young-growth California white fir were developed by using stem analysis data from 77 dominant and codominant trees growing in mixed-coniferstands on the western slopes of the Sierra Nevada. Site index reference age is 50 years at breast height. A family of 11 curves is presented for site index estimation. For more precise estimates, the site index...

  15. Growth of White fir after Douglas-fir tussock moth outbreaks: long-term records in the Sierra Nevada.

    Boyd E. Wickman

    1986-01-01

    Radial growth of white fir trees, Abies concolor (Gord. and Glend.) Lindl. ex Hildebr., defoliated almost 30 years ago by Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), in the central Sierra Nevada was compared with 22 years of growth prior to the outbreak. There was little difference in growth between the two...

  16. Engaging Youth in Community Change: Outcomes and Lessons Learned from Sierra Health Foundation's REACH Youth Program. Final Evaluation Report

    ERIC Educational Resources Information Center

    Campbell, David; Erbstein, Nancy; Fabionar, James; Wilcox, Whitney; Carrasco, Lisceth Cruz

    2010-01-01

    From 2006 to 2010, Sierra Health Foundation's REACH program committed $8 million to support the healthy development of youth in the Greater Sacramento, California, region. As a centerpiece of the larger grantmaking strategy, seven grantees in the region were selected to create community coalitions that involved both youth and adults in their…

  17. REGIONAL ANALYSIS OF INORGANIC NITROGEN YIELD AND RETENTION IN HIGH-ELEVATION ECOSYSTEMS OF THE SIERRA NEVADA AND ROCKY MOUNTAINS

    EPA Science Inventory

    Yields and retention of inorganic nitrogen (DIN) and nitrate concentrations in surface runoff are summarized for 28 high elevation watersheds in the Sierra Nevada, California and Rocky Mountains of Wyoming and Colorado. Catchments ranged in elevation from 2475 to 3603 m and from...

  18. Controls of streamflow generation in small catchments across the snow-rain transition in the southern Sierra Nevada, California

    Fengjing Liu; Carolyn Hunsaker; Roger C. Bales

    2012-01-01

    Processes controlling streamflow generation were determined using geochemical tracers for water years 2004–2007 at eight headwater catchments at the Kings River Experimental Watersheds in southern Sierra Nevada. Four catchments are snowdominated, and four receive a mix of rain and snow. Results of diagnostic tools of mixing models indicate that Ca2+...

  19. Old-growth forests in the Sierra Nevada: by type in 1945 and 1993 and ownership in 1993.

    Debby Beardsley; Charles Bolsinger; Ralph. Warbington

    1999-01-01

    This report presents estimates of old-growth forest area in the Sierra Nevada by forest type in 1993 and 1945 and by old-growth stand characteristics as they existed in 1993. Ecological old-growth definitions for each forest type are used.

  20. Let's Begin Again: Sierra On-Line and the Origins of the Graphical Adventure Game

    ERIC Educational Resources Information Center

    Nooney, Laine

    2017-01-01

    The author retells the origin story of Sierra On-Line and its historic first product, the graphical adventure game "Mystery House." She reviews the academic and journalistic writing that placed the story almost exclusively inside a narrative about early computer games, treating it as a saga of the competition between the graphic…

  1. Abundance and rates of brood parasitism by brown-headed cowbirds over an elevational gradient in the southern Sierra Nevada

    Kathryn Purcell; Jared Verner

    1999-01-01

    We studied Brown-headed Cowbird (Molothrus ater) parasitism rates in four forest types (ponderosa pine, mixed conifer, true fir, and lodgepole pine) over an elevational gradient in the southern Sierra Nevada. Cowbirds were most abundant and parasitism rates were highest at the lowest sites. All but one of 17 parasitized nests were found in the...

  2. Overstory and understory dynamics in a ponderosa pine plantation vary with stand density in the Sierra Nevada: 40-year results

    Jianwei Zhang; William W. Oliver; Martin W. Ritchie; Donald L. Neal

    2013-01-01

    We periodically measured overstory ponderosa pine (Pinus ponderosa) growth and understory cover and abundance in a long-term study on the west slope of the Sierra Nevada, California, USA. The study was established in 1969 in a 20-year-old plantation, thinned to basal areas of 9, 16, 23, 30, and 37 m2 ha-1...

  3. Influence of climate and land use on historical surface fires in pine-oak forests, Sierra Madre Occidental, Mexico

    Emily K. Heyerdahl; Ernesto Alvarado

    2003-01-01

    The rugged mountains of the Sierra Madre Occidental, in north-central Mexico, support a mosaic of diverse ecosystems. Of these, the high-elevation, temperate pine-oak forests are ecologically significant for their extensiveness and biodiversity. They cover nearly half the land area in the states of Durango and Chihuahua (42%), and comprise a similar percentage of the...

  4. A multi-scale evaluation of pack stack effects on subalpine meadow plant communities in the Sierra Nevada

    We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada mountains of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow var...

  5. Reconstruction of 20th Century Atmospheric Deposition Rates in the Sierra Nevada (California) using Spheroidal Carbonaceous Particles

    NASA Astrophysics Data System (ADS)

    Heard, A.; Sickman, J. O.; Rose, N.

    2012-12-01

    Atmospheric nitrogen deposition is altering biogeochemical cycles and ecological processes in high-elevation aquatic ecosystems. A need for stricter standards based on measurable ecological effects has been identified as an important step towards their long-term protection. One of the challenges with identifying ecological thresholds is a lack of knowledge of background conditions (pre- industrial) and changes that may have occurred prior to extensive monitoring programs. However, this information can be obtained using paleolimnological approaches. We are investigating historic atmospheric deposition in the Sierra Nevada using spheroidal carbonaceous particles (SCPs) in lake sediments. SCPs are strong geochemical indicators of anthropogenic atmospheric deposition because they are only produced by industrial combustion of fossil fuels---there are no natural sources. We detected SCPs as early as 1870 at Moat Lake in the eastern Sierra Nevada. SCP concentrations increased over time, peaking in the mid-1980's (2,399 gDM-1) while SCP accumulation rates peaked in the early 1920's (105 no, cm-2 yr-1) (Figure 1). Lakes along the western slope of the Sierra (Pear and Emerald) show similar patterns although differences vary by site and are likely explained by watershed characteristics and proximity to emission sources. SCP concentrations at Pear and Emerald lakes peak 10-15 years earlier than Moat. A consistent decrease was observed at Pear and Moat following the peak concentrations until present. Present day concentrations are 556 gDM-1 at Moat and 473 gDM-1 at Pear. At Emerald lake SCPs also initially decreased starting in 1964, but an increasing trend is observed from 1995 through present. These data improve our understanding of historic atmospheric deposition patterns and are being used to inform additional palaeolimnological research, including diatom analyses, with the broader objective of reconstructing historic nitrogen deposition and estimating critical loads for

  6. Implementing a Web-Based Decision Support System to Spatially and Statistically Analyze Ecological Conditions of the Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Nguyen, A.; Mueller, C.; Brooks, A. N.; Kislik, E. A.; Baney, O. N.; Ramirez, C.; Schmidt, C.; Torres-Perez, J. L.

    2014-12-01

    The Sierra Nevada is experiencing changes in hydrologic regimes, such as decreases in snowmelt and peak runoff, which affect forest health and the availability of water resources. Currently, the USDA Forest Service Region 5 is undergoing Forest Plan revisions to include climate change impacts into mitigation and adaptation strategies. However, there are few processes in place to conduct quantitative assessments of forest conditions in relation to mountain hydrology, while easily and effectively delivering that information to forest managers. To assist the USDA Forest Service, this study is the final phase of a three-term project to create a Decision Support System (DSS) to allow ease of access to historical and forecasted hydrologic, climatic, and terrestrial conditions for the entire Sierra Nevada. This data is featured within three components of the DSS: the Mapping Viewer, Statistical Analysis Portal, and Geospatial Data Gateway. Utilizing ArcGIS Online, the Sierra DSS Mapping Viewer enables users to visually analyze and locate areas of interest. Once the areas of interest are targeted, the Statistical Analysis Portal provides subbasin level statistics for each variable over time by utilizing a recently developed web-based data analysis and visualization tool called Plotly. This tool allows users to generate graphs and conduct statistical analyses for the Sierra Nevada without the need to download the dataset of interest. For more comprehensive analysis, users are also able to download datasets via the Geospatial Data Gateway. The third phase of this project focused on Python-based data processing, the adaptation of the multiple capabilities of ArcGIS Online and Plotly, and the integration of the three Sierra DSS components within a website designed specifically for the USDA Forest Service.

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

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

    2015-01-01

    The association analyses indicated the potential for overlap between pack stock and SNBS was minimal; only 1 percent of the potential meadow area in the SNBS herd home ranges overlapped that of pack stock meadows. There were no systematic differences in overall vegetation structure or composition, or in diversity, cover, or composition of forage species, that indicated pack stock were altering SNBS habitat or affecting their nutrition. Variation in plant species composition was influenced primarily by random differences among meadows and environmental gradients, and there was little evidence that pack stock use contributed in meaningful ways to this variation. The few differences among meadows with different levels of use by bighorn sheep and pack stock either were minor or were not in a direction consistent with negative effects of pack stock on SNBS. We conclude that the current plan for managing pack stock grazing has been successful in minimizing significant negative effects on Sierra Nevada bighorn sheep at Sequoia and Kings Canyon National Parks.

  8. Plan for a Sierra Nevada Hydrologic Observatory: Science Aims, Measurement Priorities, Research Opportunities and Expected Impacts

    NASA Astrophysics Data System (ADS)

    Bales, R.; Dozier, J.; Famiglietti, J.; Fogg, G.; Hopmans, J.; Kirchner, J.; Meixner, T.; Molotch, N.; Redmond, K.; Rice, R.; Sickman, J.; Warwick, J.

    2004-12-01

    In response to NSF's plans to establish a network of hydrologic observatories, a planning group is proposing a Sierra Nevada Hydrologic Observatory (SNHO). As argued in multiple consensus planning documents, the semi-arid mountain West is perhaps the highest priority for new hydrologic understanding. Based on input from over 100 individuals, it is proposed to initiate a mountain-range-scale study of the snow-dominated hydrology of the region, focusing on representative 1,000-5,000 km2 river basins originating in the Sierra Nevada and tributary to the Sacramento-San-Joaquin Delta. The SNHO objective is to provide the necessary infrastructure for improved understanding of surface-water and ground-water systems, their interactions and their linkages with ecosystems, biogeochemistry, agriculture, urban areas and water resources in semi-arid regions. The SNHO will include east-west transects of hydrological observations across the Sierra Nevada and into the basin and range system, in four distinct latitude bands that span much of the variability found in the semi-arid West. At least one transect will include agricultural and urban landscapes of the Great Central Valley. Investments in measurement systems will address scales from the mountain range down to the basin, headwater catchment and study plot. The intent is to provide representative measurements that will yield general knowledge as opposed to site-specific problem solving of a unique system. The broader, general science question posed by the planning group is: How do mountain hydrologic processes vary across landscapes, spanning a range of latitudes, elevations and thus climate, soils, geology and vegetation zones?\\" Embodied are additional broad questions for the hydrologic science community as a whole: (i) How do hydrologic systems that are subjected to multiple perturbations respond? (ii) How do pulses and changes propagate through the hydrologic system? (iii) What are the time lags and delays of stresses in

  9. Mineralogy and geochemistry of two metamorphosed sedimentary manganese deposits, Sierra Nevada, California, USA

    Flohr, M.J.K.; Huebner, J.S.

    1992-01-01

    Laminated to massive rhodochrosite, hausmannite, and Mn-silicates from the Smith prospect and Manga-Chrome mine, Sierra Nevada, California were deposited as ocean floor sediments associated with chert and shale. The principal lithologies at Smith are chert, argillite, rhodochrosite-, hausmannite- and chlorite-rich layers, and relatively uncommon layers of jacobsite. The Manga-Chrome mine also contains layers rich in manganoan calcite and caryopilite. Tephroite, rhodonite, spessartine, and accessory alleghanyite and sonolite formed during metamorphism. Volcaniclastic components are present at Manga-Chrome as metavolcanic clasts and as Mn-poor, red, garnet- and hematite-rich layers. There is no evidence, such as relict lithologies, that Mn was introduced into Mn-poor lithologies such as chert, limestone or mudstone. Replacement of Mn-poor phases by Mn-rich phases is observed only in the groundmass of volcanic clasts that appear to have fallen into soft Mn-rich mud. Manganiferous samples from the Smith prospect and Manga-Chrome mine have high Mn Fe and low concentrations of Ni, Cu, Zn, Co, U, Th and the rare-earth elements that are similar to concentrations reported from other ancient Mn deposits found in chert-greenstone complexes and from manganiferous sediments and crusts that are forming near modern sea floor vents. The Sierra Nevada deposits formed as precipitates of Mn-rich sediments on the sea floor, probably from mixtures of circulating hydrothermal fluids and seawater. The composition of a metabasalt from the Smith prospect is consistent with those of island-arc tholeiites. Metavolcanic clasts from the Manga-Chrome mine are compositionally distinct from the Smith metabasalt and have alkaline to calc-alkaline affinities. A back-arc basin is considered to be the most likely paleoenvironment for the formation of the Mn-rich lenses at the Manga-Chrome mine and, by association, the Smith prospect. Layers of rhodochrosite, hausmannite and chert preserve the

  10. Potential Exposure to Ebola Virus from Body Fluids due to Ambulance Compartment Permeability in Sierra Leone.

    PubMed

    Casey, Megan L; Nguyen, Duong T; Idriss, Barrie; Bennett, Sarah; Dunn, Angela; Martin, Stephen

    2015-12-01

    Prehospital care, including patient transport, is integral in the patient care process during the Ebola response. Transporting ill persons from the community to Ebola care facilities can stop community spread. Vehicles used for patient transport in infectious disease outbreaks should be evaluated for adequate infection prevention and control. An ambulance driver in Sierra Leone attributed his Ebola infection to exposure to body fluids that leaked from the patient compartment to the driver cabin of the ambulance. A convenience sample of 14 vehicles used to transport patients with suspected or confirmed Ebola in Sierra Leone were assessed. The walls separating the patient compartment and driver cabin in these vehicles were evaluated for structural integrity and potential pathways for body fluid leakage. Ambulance drivers and other staff were asked to describe their cleaning and decontamination practices. Ambulance construction and design standards from the National Fire Protection Association, US General Services Administration, and European Committee on Standardization (CEN) were reviewed. Many vehicles used by ambulance staff in Sierra Leone were not traditional ambulances, but were pick-up trucks or sport-utility vehicles that had been assembled or modified for patient transport. The wall separating the patient compartment and driver cabin in many vehicles did not have a waterproof seal around the edges. Staff responsible for cleaning and disinfection did not thoroughly clean bulk body fluids with disposable towels before disinfection of the patient compartment. Pressure from chlorine sprayers used in the decontamination process may have pushed body fluids from the patient compartment into the driver cabin through gaps around the wall. Ambulance design standards do not require a waterproof seal between the patient compartment and driver cabin. Sealing the wall by tightening or replacing existing bolts is recommended, followed by caulking of all seams with a

  11. Ensemble Simulation of Sierra Nevada Snowmelt Runoff Using a Regional Climate Modeling Approach

    NASA Astrophysics Data System (ADS)

    Holtzman, N.; Pavelsky, T.; Wrzesien, M.

    2017-12-01

    The snowmelt-dominated watersheds on the western slopes of the California Sierra Nevada drain into reservoirs that generate electricity and help irrigate Central Valley farms. At the end of the wet season of each year, around April 1, most of the water that will become runoff in these basins is stored as snow at high elevations. Snow measurements provide a good estimate of the total annual runoff to come. For efficient water management, however, it is also useful to know the timing of runoff. When and how large will the peak flow into a reservoir be, and how fast will the flow decline after it peaks? We address such questions using a coupled regional climate and land surface model, WRF and Noah-MP, to dynamically downscale the North American Regional Reanalysis (NARR) with an ensemble approach. First, we assess several methods of deriving melt-season runoff from WRF. We run WRF for a complete water year, and also test initializing WRF snow from observation-based datasets at the approximate date of peak snow water equivalent. By aggregating the modeled runoffs over the drainage basins of reservoirs and comparing to naturalized flow data, we can assess the basin-scale snow accumulation accuracy of WRF and the other datasets in the Sierra. After choosing a procedure to set the model snow at the end of the wet season, we apply in WRF the melt-season meteorology from 20 different past years of NARR to produce an ensemble of simulations, each with modeled flows into 8 reservoirs spanning the Sierra. We use the ensemble to characterize the likely spread in the timing and magnitude of hydrologic outcomes during the melt season. Probabilistic forecasts can help water-energy systems operate more efficiently. The ensemble also shows the effect of warm-season temperature extremes on flow timing, allowing human systems to prepare for those possibilities. Finally, the ensemble provides a baseline estimate of the maximum variability in runoff timing that could be generated by

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

    NASA Astrophysics Data System (ADS)

    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

  13. Impact of five annual rounds of mass drug administration with ivermectin on onchocerciasis in Sierra Leone.

    PubMed

    Koroma, Joseph B; Sesay, Santigie; Conteh, Abdul; Koudou, Benjamin; Paye, Jusufu; Bah, Mohamed; Sonnie, Mustapha; Hodges, Mary H; Zhang, Yaobi; Bockarie, Moses J

    2018-04-06

    Onchocerciasis is endemic in 12 of the 14 health districts of Sierra Leone. Good treatment coverage of community-directed treatment with ivermectin was achieved between 2005 and 2009 after the 11-year civil conflict. Sentinel site surveys were conducted in 2010 to evaluate the impact of five annual rounds of ivermectin distribution. In total, 39 sentinel villages from hyper- and meso-endemic areas across the 12 endemic districts were surveyed using skin snips in 2010. Results were analyzed and compared with the baseline data from the same 39 villages. The average microfilaridermia (MF) prevalence across 39 sentinel villages was 53.10% at baseline. The MF prevalence was higher in older age groups, with the lowest in the age group of 1-9 years (11.00%) and the highest in the age group of 40-49 years (82.31%). Overall mean MF density among the positives was 28.87 microfilariae (mf)/snip, increasing with age with the lowest in the age group of 1-9 years and the highest in the age group of 40-49 years. Males had higher MF prevalence and density than females. In 2010 after five rounds of mass drug administration, the overall MF prevalence decreased by 60.26% from 53.10% to 21.10%; the overall mean MF density among the positives decreased by 71.29% from 28.87 mf/snip to 8.29 mf/snip; and the overall mean MF density among all persons examined decreased by 88.58% from 15.33 mf/snip to 1.75 mf/snip. Ten of 12 endemic districts had > 50% reduction in MF prevalence. Eleven of 12 districts had ≥50% reduction in mean MF density among the positives. A significant reduction of onchocerciasis MF prevalence and mean density was recorded in all 12 districts of Sierra Leone after five annual MDAs with effective treatment coverage. The results suggested that the onchocerciasis elimination programme in Sierra Leone was on course to reach the objective of eliminating onchocerciasis in the country by the year 2025. Annual MDA with ivermectin should continue in all 12 districts and

  14. Inevitable changes in snowpack and water resources over California's Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Hall, A. D.; Sun, F.; Walton, D.; Berg, N.; Schwartz, M. A.

    2015-12-01

    Here we use a downscaling technique incorporating both dynamical and statistical methods to project end-of-century changes in spring snow water equivalent in California's Sierra Nevada. The technique produces outcomes for all Global Climate Models (GCMs) and the four greenhouse gas forcing scenarios adopted by the Intergovernmental Panel on Climate Change (IPCC). For all GCMs and forcing scenarios, significant snow loss occurs at elevations below 2500 meters, despite increasing precipitation in many GCMs. The loss is significantly enhanced by snow albedo feedback. The approximate intermodel range in percent of total snow remaining in the entire region is 60-85% for a likely "mitigation" scenario, and 35-55% for the "business-as-usual" scenario. Thus significant snowpack decrease by century's end is inevitable, even if the loss can be cushioned through greenhouse gas emissions reductions over the coming decades. The snowpack loss also leads to significant changes in runoff timing, which are also inevitable.

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

    Kennedy, Jeffrey R.

    2015-01-01

    This report (1) summarizes changes to the Sierra Vista Subwatershed regional time-lapse gravity network with respect to station locations and (2) presents 2014 and 2015 gravity measurements and gravity values at each station. A prior gravity network, established between 2000 and 2005, was revised in 2014 to cover a larger number of stations over a smaller geographic area in order to decrease measurement and interpolation uncertainty. The network currently consists of 59 gravity stations, including 14 absolute-gravity stations. Following above-average rainfall during summer 2014, gravity increased at all but one of the absolute-gravity stations that were observed in both June 2014 and January 2015. This increase in gravity indicates increased groundwater storage in the aquifer and (or) unsaturated zone as a result of rainfall and infiltration.

  16. Some additional observations on inclusions in the granitic rocks of the Sierra Nevada

    Dodge, F.C.W.; Kistler, R.W.

    1990-01-01

    Microgranular quartz diorite and diorite inclusions are widespread in central Sierra Nevada granitoid rocks and are almost exclusively restricted to hornblende-bearing rocks, most commonly felsic tonalites and mafic granodiorites. The Nd-Sm and Rb-Sr systematics indicate that most inclusions were in isotopic equilibrium with enclosing materials at the time of formation. Silica contents of inclusions and granitoids are contiguous, but inclusions generally contain less than, and granitoids more than, 60% SiO2. Ferric oxide and H2O+ trends relative to SiO2 suggests many inclusions formed as concentrations of hydrous mafic minerals. Variation of other major element oxides and trace elements support this inference. Most inclusions represent fragmented crystal accumulations of early-formed, near-liquidus minerals generated from these previously mixed magmas. -from Authors

  17. 75 FR 44942 - 2015 Resource Pool-Sierra Nevada Customer Service Region

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-30

    ...The Western Area Power Administration (Western), a Federal power marketing administration of the Department of Energy (DOE), published its 2004 Power Marketing Plan (Marketing Plan) for the Sierra Nevada Customer Service Region (SNR) in the Federal Register on June 25, 1999. The Marketing Plan specifies the terms and conditions under which Western will market power from the Central Valley Project (CVP) and the Washoe Project beginning January 1, 2005, and continuing through December 31, 2024. The Marketing Plan provided for a portion of SNR's resources to be reallocated through a 2015 Resource Pool. On June 3, 2009, Western published a Call for 2015 Resource Pool Applications. On September 28, 2009, Western published a Notice of Extension to file applications. This notice announces Western's proposed allocations of power from the 2015 Resource Pool.

  18. Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

    Stern, Michelle A.; Anderson, Frank A.; Flint, Lorraine E.; Flint, Alan L.

    2018-05-03

    In situ soil moisture datasets are important inputs used to calibrate and validate watershed, regional, or statewide modeled and satellite-based soil moisture estimates. The soil moisture dataset presented in this report includes hourly time series of the following: soil temperature, volumetric water content, water potential, and total soil water content. Data were collected by the U.S. Geological Survey at five locations in California: three sites in the central Sierra Nevada and two sites in the northern Coast Ranges. This report provides a description of each of the study areas, procedures and equipment used, processing steps, and time series data from each site in the form of comma-separated values (.csv) tables.

  19. Individual acoustic variation in Belding's ground squirrel alarm chirps in the High Sierra Nevada

    NASA Astrophysics Data System (ADS)

    McCowan, Brenda; Hooper, Stacie L.

    2002-03-01

    The acoustic structure of calls within call types can vary as function of individual identity, sex, and social group membership and is important in kin and social group recognition. Belding's ground squirrels (Spermophilus beldingi) produce alarm chirps that function in predator avoidance but little is known about the acoustic variability of these alarm chirps. The purpose of this preliminary study was to analyze the acoustic structure of alarm chirps with respect to individual differences (e.g., signature information) from eight Belding's ground squirrels from four different lakes in the High Sierra Nevada. Results demonstrate that alarm chirps are individually distinctive, and that acoustic similarity among individuals may correspond to genetic similarity and thus dispersal patterns in this species. These data suggest, on a preliminary basis, that the acoustic structure of calls might be used as a bioacoustic tool for tracking individuals, dispersal, and other population dynamics in Belding's ground squirrels, and perhaps other vocal species.

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

    PubMed

    Ten Bensel, Tusty; Sample, Lisa L

    2017-08-01

    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.