WorldWideScience

Sample records for networks san francisco

  1. Deployment of the National Transparent Optical Network around the San Francisco Bay Area

    Energy Technology Data Exchange (ETDEWEB)

    McCammon, K.; Haigh, R.; Armstrong, G. [and others

    1996-06-01

    We report on the deployment and initial operation of the National Transparent Optical Network, an experimental WDM network testbed around the San Francisco Bay Area, during the Optical Fiber Conference (OFC`96) held in San Jose, CA. The deployment aspects of the physical plant, optical and SONET layers are examined along with a discussion of broadband applications which utilized the network during the OFC`96 demonstration. The network features dense WDM technology, transparent optical routing technology using acousto- optic tunable filter based switches, and network modules with add/drop, multicast, and wavelength translation capabilities. The physical layer consisted of over 300 km of Sprint and Pacific Bell conventional single mode fiber which was amplified with I I optical amplifiers deployed in pre-amp, post-amp, and line amp configurations. An out-of-band control network provided datacom channels from remote equipment sites to the SONET network manager deployed at the San Jose Convention Center for the conference. Data transport over five wavelengths was achieved in the 1550 nm window using a variety of signal formats including analog and digital signal transmission on different wavelengths on the same fiber. The network operated throughout the week of OFC`96 and is still in operation today.

  2. Los Angeles og San Francisco

    DEFF Research Database (Denmark)

    Ørstrup, Finn Rude

    1998-01-01

    Kompendium udarbejdet til en studierejse til Los Angeles og San Francisco april-maj 1998 Kunstakademiets Arkitektskole, Institut 3H......Kompendium udarbejdet til en studierejse til Los Angeles og San Francisco april-maj 1998 Kunstakademiets Arkitektskole, Institut 3H...

  3. San Francisco District Laboratory (SAN)

    Data.gov (United States)

    Federal Laboratory Consortium — Program CapabilitiesFood Analysis SAN-DO Laboratory has an expert in elemental analysis who frequently performs field inspections of materials. A recently acquired...

  4. ASTER Flyby of San Francisco

    Science.gov (United States)

    2002-01-01

    The Advanced Spaceborne Thermal Emission and Reflection radiometer, ASTER, is an international project: the instrument was supplied by Japan's Ministry of International Trade and Industry. A joint US/Japan science team developed algorithms for science data products, and is validating instrument performance. With its 14 spectral bands, extremely high spatial resolution, and 15 meter along-track stereo capability, ASTER is the zoom lens of the Terra satellite. The primary mission goals are to characterize the Earth's surface; and to monitor dynamic events and processes that influence habitability at human scales. ASTER's monitoring and mapping capabilities are illustrated by this series of images of the San Francisco area. The visible and near infrared image reveals suspended sediment in the bays, vegetation health, and details of the urban environment. Flying over San Francisco (3.2MB) (high-res (18.3MB)), we see the downtown, and shadows of the large buildings. Past the Golden Gate Bridge and Alcatraz Island, we cross San Pablo Bay and enter Suisun Bay. Turning south, we fly over the Berkeley and Oakland Hills. Large salt evaporation ponds come into view at the south end of San Francisco Bay. We turn northward, and approach San Francisco Airport. Rather than landing and ending our flight, we see this is as only the beginning of a 6 year mission to better understand the habitability of the world on which we live. For more information: ASTER images through Visible Earth ASTER Web Site Image courtesy of MITI, ERSDAC, JAROS, and the U.S./Japan ASTER Science Team

  5. 78 FR 18238 - Safety Zone; SFPD Training Safety Zone; San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2013-03-26

    ... William Hawn, U.S. Coast Guard Sector San Francisco; telephone (415) 399-7442 or email at D11-PF-Marine... navigable waters around the SFPD's maritime interdiction training exercises. The SFPD Training Safety ] Zone... Hunters Point in San Francisco, CA in support of the San Francisco Police Department's maritime...

  6. 27 CFR 9.157 - San Francisco Bay.

    Science.gov (United States)

    2010-04-01

    ..., San Mateo, Santa Clara, Alameda, and Contra Costa, which border the San Francisco Bay. The area also... proceed along the San Francisco, San Mateo, and Santa Cruz County shoreline (across the Quadrangles of San... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Francisco Bay. 9.157...

  7. 78 FR 34123 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

    Science.gov (United States)

    2013-06-06

    ... NAGPRA Program, c/o Department of Anthropology, San Francisco State University, 1600 Holloway Avenue, San... construction activities for the Middle Fork American River Project. Site materials from the Middle Fork... Jeffrey Boland Fentress, San Francisco State University NAGPRA Program, c/o Department of Anthropology...

  8. 77 FR 15799 - Notice of Intent To Repatriate a Cultural Item: San Francisco State University, San Francisco, CA

    Science.gov (United States)

    2012-03-16

    ... Boland Fentress, San Francisco State University, Academic Affairs-ADM 447, San Francisco, CA 94132... identity that can be reasonably traced between the basket and the Santa Rosa Indian Community of the Santa..., San Francisco State University, Academic Affairs-ADM 447, San Francisco, CA 94132, telephone (415) 338...

  9. 77 FR 15798 - Notice of Intent To Repatriate Cultural Items: San Francisco State University, San Francisco, CA

    Science.gov (United States)

    2012-03-16

    ... Fentress, San Francisco State University, Academic Affairs-ADM 447, San Francisco, CA 94132, telephone (415.... Pursuant to 25 U.S.C. 3001(2), there is a relationship of shared group identity that can be reasonably... Boland Fentress, San Francisco State University, Academic Affairs-ADM 447, San Francisco, CA 94132...

  10. April 1906 San Francisco, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1906 San Francisco earthquake was the largest event (magnitude 8.3) to occur in the conterminous United States in the 20th Century. Recent estimates indicate...

  11. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  12. Contours--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of San Francisco map area, California. The vector data file...

  13. Habitat--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of San Francisco map area, California. The vector data file is included in...

  14. Surviving the Present: San Francisco Public Library.

    Science.gov (United States)

    Bourne, Tom

    1981-01-01

    Discusses the services of the San Francisco Public Library with respect to the effects of Proposition 13 and inflation, and describes the roles of the Main Library, the Business Branch, the Chinatown Branch, and the Communications Center. (CHC)

  15. 76 FR 81371 - Safety Zone; San Francisco New Year's Eve Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2011-12-28

    ... Captain of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with... regulated area. The PATCOM shall be designated by the Commander, Coast Guard Sector San Francisco. The...

  16. 77 FR 15260 - Safety Zone; San Francisco Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2012-03-15

    ... safety zone for the San Francisco Giants Fireworks Display in the Captain of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with the fireworks display. During the...

  17. 77 FR 37603 - Safety Zone; San Francisco Independence Day Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2012-06-22

    ... Captain of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with... regulated area. The PATCOM shall be designated by the Commander, Coast Guard Sector San Francisco. The...

  18. 76 FR 14051 - Notice of Inventory Completion: San Francisco State University, San Francisco, CA

    Science.gov (United States)

    2011-03-15

    ... American human remains. The National Park Service is not responsible for the determinations in this notice... of shared group identity that can be reasonably traced between the Native American human remains and... National Park Service Notice of Inventory Completion: San Francisco State University, San Francisco, CA...

  19. Ambient Greenhouse Gas (GHG) Observations in the San Francisco Bay Area of California Using a Fixed-site Monitoring Network

    Science.gov (United States)

    Martien, P. T.; Guha, A.; Bower, J.; Perkins, I.; Randall, S.; Young, A.; Hilken, H.; Stevenson, E.

    2016-12-01

    The Bay Area Air Quality Management District is the greater San Francisco Bay metropolitan area's chief air quality regulatory agency. Aligning itself with the Governor's Executive Order S-3-05, the Air District has set a goal to reduce the region's GHG emissions by 80% below 1990 levels by the year 2050. The Air District's 2016 Clean Air Plan will lay out the agency's vision and actions to put the region on a path forward towards achieving the 2050 goal while also reducing air pollution and related health impacts. The 2016 Plan has three overarching objectives: 1) develop a multi-pollutant emissions control strategy, (2) reduce population exposure to harmful air pollutants, especially in vulnerable communities, and (3) protect climate through a comprehensive Regional Climate Protection Strategy. To accomplish one of 2016 Plan's control measures (SL3 - Greenhouse Gas Monitoring and Measurement Network), the Air District has set up a long-term, ambient GHG monitoring network at four sites. The first site is located north and upwind of the urban core at Bodega Bay by the Pacific Coast. It mostly receives clean marine inflow and serves as the regional background site. The other three sites are strategically located at regional exit points for Bay Area plumes that presumably contain well-mixed GHG enhancements from local sources. CO2 and CH4are being measured continuously at the fixed-sites, along with combustion tracer CO and other air pollutants. In the longer term, the network will allow the Air District to monitor ambient concentrations of GHGs and thus evaluate the effectiveness of its policy, regulation and enforcement efforts. We present data trends from the first year of operation of the fixed-site monitoring network including monthly and seasonal patterns, diurnal variations and regional enhancements at individual sites above background concentrations. We also locate an isotopic methane instrument (Picarro, G132-i) for a short duration (a week) at each of the

  20. 78 FR 34895 - Safety Zone; San Francisco Independence Day Fireworks Display, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2013-06-11

    ... Display in the Captain of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards.... The PATCOM is empowered to forbid entry into and control the regulated area. The PATCOM shall be...

  1. 77 FR 59648 - Notice of Inventory Completion: San Francisco State University, NAGPRA Program, San Francisco, CA

    Science.gov (United States)

    2012-09-28

    ... Francisco State University NAGPRA Program, c/o Department of Anthropology, San Francisco State University... contains Augustine Pattern components along with ethnohistoric and historic era materials. In 1997, human... between the archeological record and historic material culture as early as 500 B.C. Ethnographic records...

  2. 78 FR 21403 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

    Science.gov (United States)

    2013-04-10

    ... NAGPRA Program, c/o Department of Anthropology, San Francisco State University, 1600 Holloway Avenue, San... conjunction with the construction of the New Don Pedro Reservoir. Site materials from the New Don Pedro...-Wuk Indians of the Tuolumne Rancheria of California. The objects are consistent with the material...

  3. An overview of San Francisco Bay PORTS

    Science.gov (United States)

    Cheng, Ralph T.; McKinnie, David; English, Chad; Smith, Richard E.

    1998-01-01

    The Physical Oceanographic Real-Time System (PORTS) provides observations of tides, tidal currents, and meteorological conditions in real-time. The San Francisco Bay PORTS (SFPORTS) is a decision support system to facilitate safe and efficient maritime commerce. In addition to real-time observations, SFPORTS includes a nowcast numerical model forming a San Francisco Bay marine nowcast system. SFPORTS data and nowcast numerical model results are made available to users through the World Wide Web (WWW). A brief overview of SFPORTS is presented, from the data flow originated at instrument sensors to final results delivered to end users on the WWW. A user-friendly interface for SFPORTS has been designed and implemented. Appropriate field data analysis, nowcast procedures, design and generation of graphics for WWW display of field data and nowcast results are presented and discussed. Furthermore, SFPORTS is designed to support hazardous materials spill prevention and response, and to serve as resources to scientists studying the health of San Francisco Bay ecosystem. The success (or failure) of the SFPORTS to serve the intended user community is determined by the effectiveness of the user interface.

  4. Morphological evolution in the San Francisco Bight

    Science.gov (United States)

    Hanes, Daniel M.; Barnard, Patrick L.

    2007-01-01

    San Francisco Bight, located near the coast of San Francisco, USA, is an extremely dynamic tidal inlet environmental subject to large waves and strong currents. Wave heights coming from the Pacific Ocean commonly exceed 5 m during winter storms. During peak flow tidal currents approach 3 m/s at the Golden Gate, a 1 km wide entrance that connects San Francisco Bay to the Pacific Ocean. Flow structure in this region varies markedly spatially and temporally due to the complex interaction by wind, waves and tidal currents. A multibeam sonar survey was recently completed that mapped in high resolution, for the first time, the bottom morphology in the region of the ebb tidal delta. This data set includes a giant sand wave field covering an area of approximately 4 square kilometers. The new survey enables the calculation of seabed change that has occurred in the past 50 years, since the last comprehensive survey of the area was completed. This comparison indicates an average erosion of 60 centimeters which equates to a total volume change of approximately 9.3 x 107 m3. Morphologic change also indicates that flood channels have filled and that the entire ebb delta is contracting radially.

  5. Advancement of Salinity and Flow Monitoring in the San Francisco Bay Delta

    Science.gov (United States)

    This report describes the utility and approximate cost of expanding the salinity water quality monitoring network along the axis of the San Francisco Estuary from Suisun Bay to Rio Vista on the Sacramento River.

  6. 77 FR 57494 - Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-09-18

    ... area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with the fireworks display. During the... regulated area. The PATCOM shall be designated by the Commander, Coast Guard Sector San Francisco. The...

  7. 77 FR 37604 - Safety Zone; Fourth of July Fireworks, City of San Francisco, San Francisco, CA

    Science.gov (United States)

    2012-06-22

    ... of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with the... direction. The PATCOM is empowered to forbid entry into and control the regulated area. The PATCOM shall be...

  8. 77 FR 70891 - Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-11-28

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Bridge Construction, San Francisco Bay..., CA in support of the Bay Bridge Construction Safety Zone from November 1, 2012 through July 31, 2013.... 1221 et seq.). CALTRANS will sponsor the Bay Bridge Construction Safety Zone on November 1, 2012...

  9. Liquefaction potential mapping for San Francisco

    Energy Technology Data Exchange (ETDEWEB)

    Kavazanjian, E.; Echezuria, H.; Roth, R.A.

    1985-01-01

    The potential of saturated deposits of cohesionless soil in downtown San Francisco to experience initial liquefaction due to seismically induced pore pressure is evaluated. Initial liquefaction, or the zero effective stress state, is used as the index of liquefaction potential because it provides the best available index for damage due to seismically induced pore pressures. Liquefaction potential is evaluated by comparing the conditional probability of liquefaction, or liquefaction susceptibility, to the expected intensity of seismic loading, or liquefaction opportunity. The probabilistic evaluation is made using a liquefaction hazard model developed by Chameau. Assuming the water table to be at the ground surface, results indicate that while no liquefaction is expected anywhere for an intensity with an annual probability of exceedance of 0.05, only the most resistant deposits will survive an event with an annual probability of exceedance of 0.02. For an event with an annual probability of exceedance of 0.01, initial liquefaction is expected to occur within all saturated, cohesionless soil deposits in the downtown San Francisco area. It must be emphasized that in dense soil deposits the consequences of initial liquefaction may be minimal because of their limited shear strain potential.

  10. Gender differences in sexual risk and sexually transmitted infections correlate with gender differences in social networks among San Francisco homeless youth.

    Science.gov (United States)

    Valente, Annie M; Auerswald, Colette L

    2013-10-01

    To explore whether gender differences in sexual risk and sexually transmitted infections (STIs) among homeless youth may be explained in part by gender differences in their social networks. Our sample includes 258 youth (64% male) recruited in San Francisco from street venues and transitional programs. Participants completed an audio computer-administered self-interview survey regarding their housing status and risk behaviors and an interviewer-administered survey regarding their social networks, and were tested for STIs (chlamydia and gonorrhea). We examined relationships between sexual risk and STI rates and social network characteristics by gender. Condom use was lower in young women than in young men, whereas young women were more likely to have an injection drug user (IDU) sex partner and to be diagnosed with an STI. Homeless young men were more likely to have stably housed contacts and same-sex friendships in their social networks than were young women. Stably housed network contacts were associated with increased condom use and decreased STI prevalence in young men. Same-sex friends were associated with increased condom use in young women. No young woman with a family member in her network had an IDU sex partner. Having a network member who had been recently incarcerated was associated with having an IDU sex partner for young women. Homeless young women's networks may place them at greater risk for STIs than young men. Increasing mainstream contacts and same-gender friendships may protect all homeless youth from STIs. Interventions addressing homeless young women's social networks may decrease their gender-disparate STI risk. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  11. Deep Borehole Instrumentation Along San Francisco Bay Bridges - 2000

    Energy Technology Data Exchange (ETDEWEB)

    Hutchings, L.; Kasameyer, P.; Turpin, C.; Long, L.; Hollfelder, J.; McEvilly, T.; Clymer, R.; Uhrhammer, R.

    2000-03-01

    This is a progress report on the Bay Bridges downhole network. Between 2 and 8 instruments have been spaced along the Dumbarton, San Mateo, Bay, and San Rafael bridges in San Francisco Bay, California. The instruments will provide multiple use data that is important to geotechnical, structural engineering, and seismological studies. The holes are between 100 and 1000 ft deep and were drilled by Caltrans. There are twenty-one sensor packages at fifteen sites. The downhole instrument package contains a three component HS-1 seismometer and three orthogonal Wilcox 731 accelerometers, and is capable of recording a micro g from local M = 1.0 earthquakes to 0.5 g strong ground motion form large Bay Area earthquakes. Preliminary results on phasing across the Bay Bridge, up and down hole wave amplification at Yerba Buena Island, and sensor orientation analysis are presented. Events recorded and located during 1999 are presented. Also, a senior thesis on the deep structure of the San Francisco Bay beneath the Bay Bridge is presented as an addendum.

  12. 78 FR 54487 - YP Western Directory LLC, San Francisco Division, Publishing Operations Group, YP Subsidiary...

    Science.gov (United States)

    2013-09-04

    ... Employment and Training Administration YP Western Directory LLC, San Francisco Division, Publishing... Zero Chaos, San Francisco, California; YP Western Directory LLC, San Francisco Division, Publishing... Assistance on February 13, 2013, applicable to workers of YP Western Directory LLC, San Francisco Division...

  13. How Many Transgender Men Are There in San Francisco?

    Science.gov (United States)

    McFarland, Willi; Wilson, Erin; Fisher Raymond, H

    2017-05-01

    The purpose of this study was to estimate the number of transgender men (transmen) adults living in San Francisco. We integrated two population size estimation methods into a community-based health survey of transmen (n = 122) in the San Francisco Bay Area in 2014-2015: the service multiplier and wisdom of the crowds. The median estimate was 806 transmen adults in San Francisco (0.11% of adults) and 4027 in the Bay Area. Considering potential biases, we believe our estimates are conservative. Knowing the denominator of persons at risk for health conditions is necessary for public health planning, surveillance, and impact evaluation.

  14. Backscatter C [8101]--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of the Offshore of San Francisco map area, California. Backscatter data are provided as separate...

  15. Folds--Offshore of San Francisco Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for folds for the geologic and geomorphic map of the Offshore of San Francisco map area, California. The vector data file is...

  16. San Francisco-Pacifica Coast Landslide Susceptibility 2011

    Data.gov (United States)

    California Department of Resources — The San Francisco-Pacifica Coast grid map was extracted from the California Geological Survey Map Sheet 58 that covers the entire state of California and originally...

  17. San Francisco Littoral Cell CRSMP Sensitive Habitat 2012

    Data.gov (United States)

    California Department of Resources — Ecological regions of interest as identified in the San Francisco Coastal Region Sediment Management Plan.NPS identifies several special management areas within the...

  18. Backscatter A [8101]--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of the Offshore of San Francisco map area, California. Backscatter data are provided as separate...

  19. Backscatter B [8101]--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of the Offshore of San Francisco map area, California. Backscatter data are provided as separate...

  20. San Francisco Bay Interferometric Side Scan Imagery: Area B

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — High resolution sonar data were collected over ultra-shallow areas of the San Francisco Bay estuary system. Bathymetric and acoustic backscatter data were collected...

  1. Backscatter D [7125]--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of the Offshore of San Francisco map area, California. Backscatter data are provided as separate...

  2. San Francisco Bay, California 1 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1-second San Francisco Bay, California Elevation Grid provides bathymetric data in ASCII raster format of 1-second resolution in geographic coordinates. This...

  3. National Status and Trends: Bioeffects Program - San Francisco Bay Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study was based on the sediment quality triad (SQT) approach. A stratified probabilistic sampling design was utilized to characterize the San Francisco Bay...

  4. Merchandising of cigarettes in San Francisco pharmacies: 27 years later

    National Research Council Canada - National Science Library

    B Eule; M K Sullivan; S A Schroeder; K S Hudmon

    2004-01-01

    Objective: To estimate changes since 1976 in the proportion of San Francisco pharmacies that sell cigarettes and to characterise the advertising of cigarettes and the merchandising of non-prescription nicotine...

  5. Faults--Offshore of San Francisco Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore San Francisco map area, California. The vector data file is included...

  6. Earthquake Damage in San Francisco, CA, April 18, 1906

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1906 San Francisco earthquake was the largest event (magnitude 8.3) to occur in the conterminous United States in the 20th Century. Recent estimates indicate...

  7. Narrative Report : San Francisco Bay NWR Complex : Fiscal Year 1974

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1974. The report begins with a general...

  8. One-Dimensional Convolutional Neural Network Land-Cover Classification of Multi-Seasonal Hyperspectral Imagery in the San Francisco Bay Area, California

    Directory of Open Access Journals (Sweden)

    Daniel Guidici

    2017-06-01

    Full Text Available In this study, a 1-D Convolutional Neural Network (CNN architecture was developed, trained and utilized to classify single (summer and three seasons (spring, summer, fall of hyperspectral imagery over the San Francisco Bay Area, California for the year 2015. For comparison, the Random Forests (RF and Support Vector Machine (SVM classifiers were trained and tested with the same data. In order to support space-based hyperspectral applications, all analyses were performed with simulated Hyperspectral Infrared Imager (HyspIRI imagery. Three-season data improved classifier overall accuracy by 2.0% (SVM, 1.9% (CNN to 3.5% (RF over single-season data. The three-season CNN provided an overall classification accuracy of 89.9%, which was comparable to overall accuracy of 89.5% for SVM. Both three-season CNN and SVM outperformed RF by over 7% overall accuracy. Analysis and visualization of the inner products for the CNN provided insight to distinctive features within the spectral-temporal domain. A method for CNN kernel tuning was presented to assess the importance of learned features. We concluded that CNN is a promising candidate for hyperspectral remote sensing applications because of the high classification accuracy and interpretability of its inner products.

  9. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  10. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  11. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  12. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1977

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  13. Benthic fluxes in San Francisco Bay

    Science.gov (United States)

    Hammond, Douglas E.; Fuller, C.; Harmon, D.; Hartman, Blayne; Korosec, M.; Miller, L.G.; Rea, R.; Warren, S.; Berelson, W.; Hager, S.W.

    1985-01-01

    Measurements of benthic fluxes have been made on four occasions between February 1980 and February 1981 at a channel station and a shoal station in South San Francisco Bay, using in situ flux chambers. On each occasion replicate measurements of easily measured substances such as radon, oxygen, ammonia, and silica showed a variability (??1??) of 30% or more over distances of a few meters to tens of meters, presumably due to spatial heterogeneity in the benthic community. Fluxes of radon were greater at the shoal station than at the channel station because of greater macrofaunal irrigation at the former, but showed little seasonal variability at either station. At both stations fluxes of oxygen, carbon dioxide, ammonia, and silica were largest following the spring bloom. Fluxes measured during different seasons ranged over factors of 2-3, 3, 4-5, and 3-10 (respectively), due to variations in phytoplankton productivity and temperature. Fluxes of oxygen and carbon dioxide were greater at the shoal station than at the channel station because the net phytoplankton productivity is greater there and the organic matter produced must be rapidly incorporated in the sediment column. Fluxes of silica were greater at the shoal station, probably because of the greater irrigation rates there. N + N (nitrate + nitrite) fluxes were variable in magnitude and in sign. Phosphate fluxes were too small to measure accurately. Alkalinity fluxes were similar at the two stations and are attributed primarily to carbonate dissolution at the shoal station and to sulfate reduction at the channel station. The estimated average fluxes into South Bay, based on results from these two stations over the course of a year, are (in mmol m-2 d-1): O2 = -27 ?? 6; TCO2 = 23 ?? 6; Alkalinity = 9 ?? 2; N + N = -0.3 ?? 0.5; NH3 = 1.4 ?? 0.2; PO4 = 0.1 ?? 0.4; Si = 5.6 ?? 1.1. These fluxes are comparable in magnitude to those in other temperate estuaries with similar productivity, although the seasonal

  14. Adventure capitalists in "Maya Town": ethnographic insights on transnational social networks and migration from the de-territorialized state of Yucatan to San Francisco, California

    OpenAIRE

    Cornejo, Salvador Contreras

    2009-01-01

    This study is about the migration of young men from the town of Oxkutzcab in the Yucatan peninsula of Mexico who against historical and contemporary structural conditions (Maya versus nation-state, globalizing of local economy, world system and free trade agreements) have chosen international migration as a strategy for survival and success. The purpose of this research is to illustrate the fundamental role of circular migration to and from San Francisco, California and Oxkutzc...

  15. Dos edificios administrativos, en San Francisco

    Directory of Open Access Journals (Sweden)

    Skidmore, Owings & Merrill, Arquitectos

    1964-07-01

    Full Text Available The Crown Zellerbach has been built on a large triangular plaza, at the outskirts of San Francisco. This is one of the most recent tall buildings in the city. The Wells Fargo Bank is also situated on this plaza. It is of special interest, both as regards its shape and functional organisation. It has a ground floor, where most of the mercantile activities take place, and a basement, containing a Council room; the strong rooms, with 2,500 private boxes as well as the bank's own safe; washing rooms; mechanical equipment rooms; a rest room; a bar for the employees and independent stairs. The building has a circular planform, 21.5 m in diameter and 354 m2 in area. The structure is metallic, the vertical supports are along the periphery, spaced every 1.626 m. The enclosing curtain walls are glass and anodized aluminium. The roof has radially distributed metal beams, interconnected by prefabricated concrete units, covered with copper sheeting. This bank, shaped like a hunting lodge, and finished with delicate care, contrasts sharply with the powerful volume of the Crown Zellerbach, and of other nearby buildings, and adds distinction to the plaza.Sobre una gran plaza triangular del extrarradio de San Francisco se alzan: el Crown Zellerbach, uno de sus más recientes rascacielos, y un bello pabellón independiente, el Wells Fargo Bank. El resto de la plaza es de dominio público. La originalidad, en forma y organización del segundo, ha hecho que le dediquemos la mayor atención: consta de una planta baja, en la que se desarrollan, prácticamente, todas las actividades mercantiles, y un piso inferior, en donde se distribuyen: un Salón de Consejos, el departamento de cajas de seguridad, con 2.500 unidades, y las cajas del Banco, los aseos, equipos mecánicos, etc., una sala de descanso y bar para los empleados, con escalera de acceso independiente. Tiene planta circular, de 21,5 m de diámetro y 354 m2 de superficie. La estructura es metálica, con

  16. San Francisco Bay Area Baseline Trash Loading Summary Results, San Francisco Bay Area CA, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Area stormwater permit sets trash control guidelines for discharges through the storm drain system. The permit covers Alameda, Contra Costa,...

  17. San Francisco Bay Water Quality Improvement Fund Project Locations, San Francisco CA, 2017, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  18. San Francisco Bay Water Quality Improvement Fund Map Service, San Francisco CA, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  19. 2010 Northern San Francisco Bay Area Lidar: Portions of Alameda, Contra Costa, Marin, Napa, San Francisco, Solano, and Sonoma Counties

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Light Detection and Ranging (LiDAR) dataset is a survey of northern San Francisco Bay, California. The project area consists of approximately 437 square miles...

  20. ASTER Images San Francisco Bay Area

    Science.gov (United States)

    2000-01-01

    These images of the San Francisco Bay region were acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. Each covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet.Upper Left: The color infrared composite uses bands in the visible and reflected infrared. Vegetation is red, urban areas are gray; sediment in the bays shows up as lighter shades of blue. Thanks to the 15 meter (50-foot) spatial resolution, shadows of the towers along the Bay Bridge can be seen.Upper right: A composite of bands in the short wave infrared displays differences in soils and rocks in the mountainous areas. Even though these regions appear entirely vegetated in the visible, enough surface shows through openings in the vegetation to allow the ground to be imaged.Lower left: This composite of multispectral thermal bands shows differences in urban materials in varying colors. Separation of materials is due to differences in thermal emission properties, analogous to colors in the visible.Lower right: This is a color coded temperature image of water temperature, derived from the thermal bands. Warm waters are in white and yellow, colder waters are blue. Suisun Bay in the upper right is fed directly from the cold Sacramento River. As the water flows through San Pablo and San Francisco Bays on the way to the Pacific, the waters warm up.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for

  1. Café Takksemi - og aðrir tankar úr San Francisco

    DEFF Research Database (Denmark)

    Simonsen, Kim

    2011-01-01

    Travel essay about literature and the image of San Francisco seen through different areas of the city.......Travel essay about literature and the image of San Francisco seen through different areas of the city....

  2. Vabariigi aastapäev San Franciscos / Heino Valvur ; foto: Heino Valvur

    Index Scriptorium Estoniae

    Valvur, Heino

    2006-01-01

    veebruarikuu möödus San Franciscos Eesti Vabariigi 88. aastapäeva pühitsedes: traditsiooniliselt tähistas aastapäeva San Francisco Seenioride Klubi koosviibimisega, E.E.L.K. San Francisco koguduses peeti jumalateenistus ja koosviibimine, kus noored esitasid rahvalaule, San Francisco Eesti Selts tähistas aastapäeva 25. veebruaril aktuse ja koosviibimisega

  3. 75 FR 65985 - Safety Zone: Epic Roasthouse Private Party Firework Display, San Francisco, CA

    Science.gov (United States)

    2010-10-27

    ... off Epic Roasthouse Restaurant, San Francisco, CA during a fireworks display in support of the Epic... Restaurant, San Francisco, CA. The fireworks display is meant for entertainment purposes. This safety zone is... Epic Roasthouse Restaurant, San Francisco, CA. The fireworks launch site will be located in position 37...

  4. 76 FR 9709 - Water Quality Challenges in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary

    Science.gov (United States)

    2011-02-22

    ... AGENCY 40 CFR Chapter I RIN-2009-ZA00 Water Quality Challenges in the San Francisco Bay/Sacramento-San... water quality conditions affecting aquatic resources in the San Francisco Bay/ Sacramento-San Joaquin... Estuary that would be constructive, including enforcement, research, revisions to water quality standards...

  5. Auckland--New Zealand's Los Angeles or San Francisco?

    Science.gov (United States)

    Bogunovich, Dushko

    1995-01-01

    Compares Auckland (New Zealand) with San Francisco (California) in terms of topographical structure, geographic location, and urban development. Both cities contain striking similarities. Maintains that Auckland can become a world-class city renowned for its beauty if developers and government work in tandem. (MJP)

  6. Cultural Factors Related to Smoking in San Francisco's Irish Bars

    Science.gov (United States)

    Satterlund, Travis D.; Antin, Tamar M. J.; Lee, Juliet P.; Moore, Roland S.

    2009-01-01

    California's Smoke-Free Workplace Act was extended to include bars in 1998. While the majority of bars in the state have become smoke free, in many bars patrons and staff continue to smoke despite the law. The authors present findings from a study which assessed cultural factors related to continued smoking in bars in the city of San Francisco. In…

  7. 77 FR 59969 - Notice of Inventory Completion: San Francisco State University, Department of Anthropology, San...

    Science.gov (United States)

    2012-10-01

    ... Anthropology, San Francisco, CA; Correction AGENCY: National Park Service, Interior. ACTION: Notice; correction... Department of Anthropology). The human remains and associated funerary objects were removed from Marin County... University staff under the direction of Gary Pahl. Materials from the excavations were jointly curated by San...

  8. Sand waves at the mouth of San Francisco Bay, California

    Science.gov (United States)

    Gibbons, Helen; Barnard, Patrick L.

    2007-01-01

    The U.S. Geological Survey; California State University, Monterey Bay; U.S. Army Corps of Engineers; National Oceanic and Atmospheric Administration; and Center for Integrative Coastal Observation, Research and Education partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. View eastward, through the Golden Gate into central San Francisco Bay. Depth of sea floor color coded: red (less than 10 m deep) to purple (more than 100 m deep). Land from USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). Sand waves in this view average 6 m in height and 80 m from crest to crest. Golden Gate Bridge is about 2 km long. Vertical exaggeration is approximately 4x for sea floor, 2x for land.

  9. Aggregate Settling Velocities in San Francisco Estuary Margins

    Science.gov (United States)

    Allen, R. M.; Stacey, M. T.; Variano, E. A.

    2015-12-01

    One way that humans impact aquatic ecosystems is by adding nutrients and contaminants, which can propagate up the food web and cause blooms and die-offs, respectively. Often, these chemicals are attached to fine sediments, and thus where sediments go, so do these anthropogenic influences. Vertical motion of sediments is important for sinking and burial, and also for indirect effects on horizontal transport. The dynamics of sinking sediment (often in aggregates) are complex, thus we need field data to test and validate existing models. San Francisco Bay is well studied and is often used as a test case for new measurement and model techniques (Barnard et al. 2013). Settling velocities for aggregates vary between 4*10-5 to 1.6*10-2 m/s along the estuary backbone (Manning and Schoellhamer 2013). Model results from South San Francisco Bay shoals suggest two populations of settling particles, one fast (ws of 9 to 5.8*10-4 m/s) and one slow (ws of Brand et al. 2015). While the open waters of San Francisco Bay and other estuaries are well studied and modeled, sediment and contaminants often originate from the margin regions, and the margins remain poorly characterized. We conducted a 24 hour field experiment in a channel slough of South San Francisco Bay, and measured settling velocity, turbulence and flow, and suspended sediment concentration. At this margin location, we found average settling velocities of 4-5*10-5 m/s, and saw settling velocities decrease with decreasing suspended sediment concentration. These results are consistent with, though at the low end of, those seen along the estuary center, and they suggest that the two population model that has been successful along the shoals may also apply in the margins.

  10. The phytoplankton component of seston in San Francisco Bay

    Science.gov (United States)

    Wienke, S.M.; Cloern, J.E.

    1987-01-01

    Phytoplankton biomass (as carbon) was estimated from chlorophyll a concentrations (Chla) and a mean value for the ratio of phytoplankton carbon to chlorophyll a in San Francisco Bay. The ratio was determined as the slope of a Model II regression of POC' against (Chla), where POC' is total particulate organic carbon minus sediment-associated non-phytoplankton carbon. Samples from 30 fixed sites in the channel and lateral shoals of San Francisco Bay were collected once or twice a month from April to November 1980, and at irregular intervals in South Bay during 1984 and 1985. For all data the calculated mean value of phytoplankton C:Chla was 51 (95% confidence interval = 47-54). No significant differences were found in the C:Chla ratio between shallow and deep sites (where light availability differs) or between northern and southern San Francisco Bay (where phytoplankton community composition differs). Using the mean C:Chla ratio of 51, we calculated that phytoplankton biomass constitutes about one third of seston carbon under most circumstances, but this fraction ranges from about 95% during phytoplankton blooms to less than 20% during spring periods of low phytoplankton biomass and high suspended sediment concentration. ?? 1987.

  11. Microbial diversity in restored wetlands of San Francisco Bay

    Energy Technology Data Exchange (ETDEWEB)

    Theroux, Susanna [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Hartman, Wyatt [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; He, Shaomei [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Univ. of Wisconsin, Madison, WI (United States); Tringe, Susannah [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.

    2013-12-09

    Wetland ecosystems may serve as either a source or a sink for atmospheric carbon and greenhouse gases. This delicate carbon balance is influenced by the activity of belowground microbial communities that return carbon dioxide and methane to the atmosphere. Wetland restoration efforts in the San Francisco Bay-Delta region may help to reverse land subsidence and possibly increase carbon storage in soils. However, the effects of wetland restoration on microbial communities, which mediate soil metabolic activity and carbon cycling, are poorly studied. In an effort to better understand the underlying factors which shape the balance of carbon flux in wetland soils, we targeted the microbial communities in a suite of restored and historic wetlands in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we profiled the diversity and metabolic potential of the wetland soil microbial communities along biogeochemical and wetland age gradients. Our results show relationships among geochemical gradients, availability of electron acceptors, and microbial community composition. Our study provides the first genomic glimpse into microbial populations in natural and restored wetlands of the San Francisco Bay-Delta region and provides a valuable benchmark for future studies.

  12. Estimates of suspended sediment entering San Francisco Bay from the Sacramento and San Joaquin Delta, San Francisco Bay, California

    Science.gov (United States)

    McKee, L.J.; Ganju, N.K.; Schoellhamer, D.H.

    2006-01-01

    This study demonstrates the use of suspended-sediment concentration (SSC) data collected at Mallard Island as a means of determining suspended-sediment load entering San Francisco Bay from the Sacramento and San Joaquin River watersheds. Optical backscatter (OBS) data were collected every 15 min during water years (WYs) 1995-2003 and converted to SSC. Daily fluvial advective sediment load was estimated by combining estimated Delta outflow with daily averaged SSC. On days when no data were available, SSC was estimated using linear interpolation. A model was developed to estimate the landward dispersive load using velocity and SSC data collected during WYs 1994 and 1996. The advective and dispersive loads were summed to estimate the total load. Annual suspended-sediment load at Mallard Island averaged 1.2??0.4 Mt (million metric tonnes). Given that the average water discharge for the 1995-2003 period was greater than the long -term average discharge, it seems likely that the average suspended-sediment load may be less than 1.2??0.4 Mt. Average landward dispersive load was 0.24 Mt/yr, 20% of the total. On average during the wet season, 88% of the annual suspended-sediment load was discharged through the Delta and 43% occurred during the wettest 30-day period. The January 1997 flood transported 1.2 Mt of suspended sediment or about 11% of the total 9-year load (10.9 Mt). Previous estimates of sediment load at Mallard Island are about a factor of 3 greater because they lacked data downstream from riverine gages and sediment load has decreased. Decreasing suspended-sediment loads may increase erosion in the Bay, help to cause remobilization of buried contaminants, and reduce the supply of sediment for restoration projects. ?? 2005 Elsevier B.V. All rights reserved.

  13. Don Edwards San Francisco Bay National Wildlife Refuge: Annual Narrative Report: Calendar Year 2000

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Don Edwards San Francisco Bay NWR, Antioch Dunes NWR, Farallon NWR, San Pablo Bay NWR, Ellicot Slough NWR, Salinas River NWR, and...

  14. San Francisco Bay National Wildlife Refuge: Annual Narrative Report: Calendar Year 1987

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for San Francisco Bay NWR, San Pablo Bay NWR, Antioch Dunes NWR, Farallon NWR, and Ellicott Slough NWR outlines Refuge accomplishments...

  15. San Francisco Bay National Wildlife Refuge Complex: Annual Narrative Report: Calendar Year 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for San Francisco Bay NWR, San Pablo Bay NWR, Antioch Dunes NWR, Farallon NWR, Ellicott Slough NWR, and Salinas River NWR outlines...

  16. San Francisco Bay National Wildlife Refuge: Annual Narrative Report: Calendar Year 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for San Francisco Bay NWR, San Pablo Bay NWR, Antioch Dunes NWR, Farallon NWR, Ellicott Slough NWR, and Salinas River NWR outlines...

  17. Final Environmental Statement : Acquisition of lands for the San Francisco Bay National Wildlife Refuge California

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Federal Government proposes to acquire approximately 23,000 acres of land in the South San Francisco Bay region, Alameda, San Mateo and Santa Clara Counties, to...

  18. Mercury-contaminated hydraulic mining debris in San Francisco Bay

    Science.gov (United States)

    Bouse, Robin M.; Fuller, Christopher C.; Luoma, Samuel N.; Hornberger, Michelle I.; Jaffe, Bruce E.; Smith, Richard E.

    2010-01-01

    The hydraulic gold-mining process used during the California Gold Rush and in many developing countries today contributes enormous amounts of sediment to rivers and streams. Commonly, accompanying this sediment are contaminants such as elemental mercury and cyanide used in the gold extraction process. We show that some of the mercurycontaminated sediment created by hydraulic gold mining in the Sierra Nevada, between 1852 and 1884, ended up over 250 kilometers (km) away in San Francisco Bay; an example of the far-reaching extent of contamination from such activities.

  19. Perspective View with Landsat Overlay, San Francisco Bay Area, Calif.

    Science.gov (United States)

    2002-01-01

    The cities of San Francisco and the East Bay are highlighted in this computer-generated perspective viewed from west of the Golden Gate. San Francisco occupies the peninsula jutting into the picture from the right. Golden Gate Park is the long rectangle near its left end and the Presidiois the green area at its tip, from which Golden Gate Bridge crosses to Marin. Treasure Island is the bright spot above San Francisco and Alcatraz Island is the small smudge below and to the left. Across the bay from San Francisco lie Berkeley (left) and Oakland (right). Mount Diablo, a landmark visible for many miles, rises in the distance at the upper right.This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 5 satellite image. Colors are from Landsat bands 3, 2, and 1 as red, green and blue, respectively. Topographic expression is exaggerated two times.Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter (98-foot) resolution of most Landsat images and will substantially help in analyzing the large and growing Landsat image archive.The Landsat Thematic Mapper image used here came from an on-line mosaic of Landsat images for the continental United States (http://mapus.jpl.nasa.gov), a part of NASA's Digital Earth effort.Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission

  20. 77 FR 28771 - Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2012-05-16

    ... Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with the fireworks display. During... forbid entry into and control the regulated area. The PATCOM shall be designated by the Commander, Coast...

  1. 78 FR 20792 - Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2013-04-08

    ... Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards associated with the fireworks display. During... forbid entry into and control the regulated area. The PATCOM shall be designated by the Commander, Coast...

  2. Record-high specific conductance and water temperature in San Francisco Bay during water year 2015

    Science.gov (United States)

    Work, Paul; Downing-Kunz, Maureen; Livsey, Daniel

    2017-02-22

    The San Francisco estuary is commonly defined to include San Francisco Bay (bay) and the adjacent Sacramento–San Joaquin River Delta (delta). The U.S. Geological Survey (USGS) has operated a high-frequency (15-minute sampling interval) water-quality monitoring network in San Francisco Bay since the late 1980s (Buchanan and others, 2014). This network includes 19 stations at which sustained measurements have been made in the bay; currently, 8 stations are in operation (fig. 1). All eight stations are equipped with specific conductance (which can be related to salinity) and water-temperature sensors. Water quality in the bay constantly changes as ocean tides force seawater in and out of the bay, and river inflows—the most significant coming from the delta—vary on time scales ranging from those associated with storms to multiyear droughts. This monitoring network was designed to observe and characterize some of these changes in the bay across space and over time. The data demonstrate a high degree of variability in both specific conductance and temperature at time scales from tidal to annual and also reveal longer-term changes that are likely to influence overall environmental health in the bay.In water year (WY) 2015 (October 1, 2014, through September 30, 2015), as in the preceding water year (Downing-Kunz and others, 2015), the high-frequency measurements revealed record-high values of specific conductance and water temperature at several stations during a period of reduced freshwater inflow from the delta and other tributaries because of persistent, severe drought conditions in California. This report briefly summarizes observations for WY 2015 and compares them to previous years that had different levels of freshwater inflow.

  3. The Unimpressible Race. A Century of Educational Struggle by the Chinese in San Francisco.

    Science.gov (United States)

    Low, Victor

    This book traces the history of the Chinese experience in America, particularly in the San Francisco area, from the California Gold Rush era of the 1850s to the construction of a new all-Chinese school in San Francisco's Chinatown district in the 1950s. The first five chapters of the book detail the withholding of school privileges from both…

  4. Tuberculosis in Mexican-born persons in San Francisco: reactivation, acquired infection and transmission.

    Science.gov (United States)

    Jasmer, R M; Ponce de Leon, A; Hopewell, P C; Alarcon, R G; Moss, A R; Paz, E A; Schecter, G F; Small, P M

    1997-12-01

    San Francisco, California. To determine the relative contributions of infection acquired in San Francisco and reactivation of tuberculous infection acquired elsewhere in Mexican-born persons who developed tuberculosis in San Francisco, and to determine the frequency of transmission leading to secondary cases of tuberculosis in other persons. The study population consisted of all Mexican-born tuberculosis patients reported in San Francisco from 1991 through June 1995. All patients had positive cultures for Mycobacterium tuberculosis and DNA fingerprinting of isolates using IS6110 with more than two bands. Patients were classified as infected in San Francisco or infected elsewhere based on pre-defined criteria that included a second DNA fingerprinting technique (polymorphic guanine-cytosine-rich sequence), chart reviews, and selected patient interviews. Of the 43 Mexican-born patients studied, nine (21%) met the definition of infection acquired in San Francisco and 34 (79%) met the definition of reactivation of infection acquired elsewhere. Only one of the 43 cases resulted in two secondary cases in US-born persons. One-fifth of the Mexican-born patients who developed tuberculosis in San Francisco acquired their tuberculous infection in San Francisco; transmission from Mexican-born persons leading to tuberculosis in other persons is uncommon.

  5. 33 CFR 167.405 - Off San Francisco: Main ship channel.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Off San Francisco: Main ship channel. 167.405 Section 167.405 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Separation Schemes and Precautionary Areas Pacific West Coast § 167.405 Off San Francisco: Main ship channel...

  6. Projected Bioclimatic Change for the San Francisco Bay Area

    Science.gov (United States)

    Torregrosa, A.; Taylor, M.; Flint, L. E.; Flint, A. L.; Weiss, S. B.

    2011-12-01

    Past and future climate data for the San Francisco Bay Area were classified using the Rivas-Martinez (R-M) system to group long-term annual climate averages into categories with biotic significance based on thermotypic and ombrotypic regimes. Bioclimate maps were generated at 270 meter resolution for ten San Francisco Bay Area counties for six 30-year periods from 1911 to 2100 which include the historical 1) 1911-1940, 2) 1941-1970, 3) 1971-2000, and future 4) 2011-2040, 5) 2041-2070, and 6) 2071-2100. Historic averages were generated from PRISM climate data. Future climate projections were generated from two IPCC-based future scenarios (A2 and B1) and two coupled atmosphere-ocean general circulation models (NOAA Geophysical Fluid Dynamics Laboratory and the Parallel Climate Model). Strong congruence was found among the boundaries for historic bioclimates and current vegetation types. However, future scenarios had varying patterns of losses and gains in bioclimate classes and these tracked mesoclimate gradients. Comparisons between projected bioclimatic categories and modeled future climatic water deficit show strong correspondence except in zones of deep alluvial deposits. Maps show areas of bioclimatic stability, e.g. areas that did not change under any future projection, versus areas with significant bioclimatic shifts in all future scenarios. These analyses and maps will be useful for assessing natural resource vulnerability to climate change and natural resource conservation-based climate adaptation decisions.

  7. Lessons from monitoring water quality in San Francisco Bay

    Science.gov (United States)

    Cloern, J.E.; Schraga, T.S.; Lopez, C.B.; Labiosa, R.

    2003-01-01

    San Francisco Bay is the defining landscape feature of the place we call ‘The Bay Area,’ but most of us only experience the Bay as we view it from an airplane window or drive across one of its bridges. These views from afar suggest that the Bay is static and sterile, but this impression is deceptive. If you are one of the many thousands of students who have experienced the Bay through a school excursion with the Marine Science Institute or other educational programs, you observed its rich plankton soup under a microscope, sorted clams and worms and crustaceans from mud samples, and identified the gobies, sole, halibut, bat rays, sharks, sardines, and smelt caught with trawls. San Francisco Bay is much more than a landscape feature. It is a dynamic ecosystem, continually changing and teeming with life. The Bay once supported the most valuable fisheries on the west coast of the United States, but commercial fishing for shellfish, shrimp, sturgeon, shad, salmon, and striped bass ended many decades ago because of habitat loss, pollution, invasive species and over harvest.

  8. Injection risk behavior among women syringe exchangers in San Francisco.

    Science.gov (United States)

    Lum, Paula J; Sears, Clare; Guydish, Joseph

    2005-01-01

    Women who inject drugs in cities where syringe exchange programs (SEPs) are well established may have different risks for HIV infection. In 1997, we interviewed 149 female syringe exchangers in San Francisco, CA, a city with high rates of injection drug use that is home to one of the largest and oldest SEPs in the United States. In this report, we describe their sociodemographics, health, and risk behavior, and we examine factors associated with recent syringe sharing. Fifty percent of respondents were women of color and the median age was 38 years. Most (86%) injected heroin and nearly half were currently homeless or had recently been incarcerated. One-third of all women reported needle sharing in the prior month. This was higher than the rate of needle sharing reported by a mixed gender sample of San Francisco exchangers in 1993, although it resembled the rate reported by a mixed gender sample in 1992. In a multivariate analysis, syringe sharing was associated with age, housing status, and sexual partnerships. Syringe sharers were more likely to be young, homeless, or have a sexual partner who was also an injection drug user. While wide access to sterile syringes is an important strategy to reduce HIV transmission among injection drug users (IDU), syringe exchange alone cannot eradicate risky injection by female IDU. Additional efforts to reduce risky injection practices should focus on younger and homeless female IDU, as well as address selective risk taking between sexual partners.

  9. Proceedings of the Fourth Social Aspects and Recreation Research Symposium: February 4-6, 2004, San Francisco, California

    Science.gov (United States)

    Patrick T. Tierney; Deborah J. (Tech. coords.) Chavez

    2004-01-01

    The Fourth Social Aspects and Recreation Research (SARR) Symposium was held February 4-6, 2004 in San Francisco, California at the Presidio of San Francisco, a component of Golden Gate National Recreation Area and at San Francisco State University. The theme was: Linking People to the Outdoors: Connections for Healthy Lands, People and Communities.

  10. 77 FR 28895 - Don Edwards San Francisco Bay National Wildlife Refuge, Alameda, Santa Clara, and San Mateo...

    Science.gov (United States)

    2012-05-16

    ... Fish and Wildlife Service Don Edwards San Francisco Bay National Wildlife Refuge, Alameda, Santa Clara, and San Mateo Counties, CA AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of availability... Wildlife Refuge, located in the Alameda, Santa Clara, and San Mateo Counties of California, consists of...

  11. Investments in the future of behavioral science: the University of California, San Francisco, Visiting Professors Program.

    Science.gov (United States)

    Dolcini, M Margaret; Grinstead Reznick, Olga A; Marín, Barbara V

    2009-04-01

    A need exists for the promotion of diversity in the scientific workforce to better address health disparities. In response to this need, funding agencies and institutions have developed programs to encourage ethnic-minority and early-career scientists to pursue research careers. We describe one such program, the University of California, San Francisco, Visiting Professors Program, which trains scientists to conduct HIV/AIDS-related research in communities of color. The program provides training and mentoring in navigating grant processes and developing strong research proposals and provides crucial networking opportunities. Although this program is focused on community-based HIV prevention, its principles and methods are widely applicable.

  12. Steam, solarization, and tons of prevention: the San Francisco Public Utilities Commission's fight to contain Phytophthoras in San Francisco Bay area restoration sites

    Science.gov (United States)

    Greg Lyman; Jessica Appel; Mia Ingolia; Ellen Natesan; Joe Ortiz

    2017-01-01

    To compensate for unavoidable impacts associated with critical water infrastructure capital improvement projects, the San Francisco Public Utilities Commission (SFPUC) restored over 2,050 acres of riparian, wetland, and upland habitat on watershed lands in Alameda, Santa Clara, and San Mateo Counties. Despite strict bio-sanitation protocols, plant pathogens (...

  13. Microplastic contamination in the San Francisco Bay, California, USA.

    Science.gov (United States)

    Sutton, Rebecca; Mason, Sherri A; Stanek, Shavonne K; Willis-Norton, Ellen; Wren, Ian F; Box, Carolynn

    2016-08-15

    Despite widespread detection of microplastic pollution in marine environments, data describing microplastic abundance in urban estuaries and microplastic discharge via treated municipal wastewater are limited. This study presents information on abundance, distribution, and composition of microplastic at nine sites in San Francisco Bay, California, USA. Also presented are characterizations of microplastic in final effluent from eight wastewater treatment plants, employing varying treatment technologies, that discharge to the Bay. With an average microplastic abundance of 700,000particles/km(2), Bay surface water appears to have higher microplastic levels than other urban waterbodies sampled in North America. Moreover, treated wastewater from facilities that discharge into the Bay contains considerable microplastic contamination. Facilities employing tertiary filtration did not show lower levels of contamination than those using secondary treatment. As textile-derived fibers were more abundant in wastewater, higher levels of fragments in surface water suggest additional pathways of microplastic pollution, such as stormwater runoff. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. A molecular epidemiological assessment of extrapulmonary tuberculosis in San Francisco.

    Science.gov (United States)

    Ong, Adrian; Creasman, Jennifer; Hopewell, Philip C; Gonzalez, Leah C; Wong, Maida; Jasmer, Robert M; Daley, Charles L

    2004-01-01

    The epidemiology of extrapulmonary tuberculosis (TB) is not well understood. We studied all cases of extrapulmonary TB reported in San Francisco during 1991-2000 to determine risk factors for extrapulmonary TB and the proportion caused by recent infection. Isolates were analyzed by IS6110-based restriction fragment-length polymorphisms analysis. There were 480 cases of extrapulmonary TB, of which 363 (76%) were culture positive; isolates were genotyped for 301 cases (83%). Multivariate analysis identified young age, female sex, and HIV infection as independent risk factors for nonrespiratory TB (excluding pulmonary, pleural, and disseminated TB). Pleural TB was less common in HIV-seropositive persons and women than were nonrespiratory forms of extrapulmonary TB. Pleural TB is different from other forms of extrapulmonary TB and is associated with the highest clustering rate (35% of cases) of all forms of TB. This high rate of clustering occurs because pleural TB is often an early manifestation of recent infection.

  15. Biological effects of anthropogenic contaminants in the San Francisco Estuary

    Science.gov (United States)

    Thompson, B.; Adelsbach, T.; Brown, C.; Hunt, J.; Kuwabara, J.; Neale, J.; Ohlendorf, H.; Schwarzbach, S.; Spies, R.; Taberski, K.

    2007-01-01

    Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to summarize information about biological effects on the Estuary's plankton, benthos, fish, birds, and mammals, gathered since the early 1990s, focusing on key accomplishments. These studies have been conducted at all levels of biological organization (sub-cellular through communities), but have included only a small fraction of the organisms and contaminants of concern in the region. The studies summarized provide a body of evidence that some contaminants are causing biological impacts in some biological resources in the Estuary. However, no general patterns of effects were apparent in space and time, and no single contaminant was consistently related to effects among the biota considered. These conclusions reflect the difficulty in demonstrating biological effects due specifically to contamination because there is a wide range of sensitivity to contaminants among the Estuary's many organisms. Additionally, the spatial and temporal distribution of contamination in the Estuary is highly variable, and levels of contamination covary with other environmental factors, such as freshwater inflow or sediment-type. Federal and State regulatory agencies desire to develop biological criteria to protect the Estuary's biological resources. Future studies of biological effects in San Francisco Estuary should focus on the development of meaningful indicators of biological effects, and on key organism and contaminants of concern in long-term, multifaceted studies that include laboratory and field experiments to determine cause and effect to adequately inform management and regulatory decisions. ?? 2006 Elsevier Inc. All rights reserved.

  16. The plight of gay visibility: intolerance in San Francisco, 1970-1979.

    Science.gov (United States)

    Roberts, Nicole E

    2013-01-01

    During the 1970s, San Francisco was often characterized as the "Gay Mecca" of the United States. While it's true that San Francisco was more supportive of the gay community during this period, this depiction often dismisses the problematic side of the increasing visibility of homosexuals. As with the increasing visibility of any minority group who is struggling to find its place in a community, the homosexual population in San Francisco soon found itself the target of anti-gay harassment and violence. This article hopes to elaborate on the published reports of intolerance that were chronicled by the gay community's own press.

  17. Demography of the San Francisco gartersnake in coastal San Mateo County, California

    Science.gov (United States)

    Halstead, Brian J.; Wylie, Glenn D.; Amarello, Melissa; Smith, Jeffrey J.; Thompson, Michelle E.; Routman, Eric J.; Casazza, Michael L.

    2011-01-01

    The San Francisco gartersnake Thamnophis sirtalis tetrataenia has been federally listed as endangered since 1967, but little demographic information exists for this species. We examined the demography of a San Francisco gartersnake population on approximately 213 ha of California coastal prairie in San Mateo County, California, from 2007 to 2010. The best-supported mark-recapture model indicated annual variation in daily capture probabilities and annual survival rates. Abundance increased throughout the study period, with a mean total population from 2008 to 2010 of 443 (95% CI = 313-646) individuals. Annual survival was slightly greater than that of most other gartersnakes, with an annual probability of survival of 0.78 (0.55-0.95) in 2008-2009 and 0.75 (0.49-0.93) in 2009-2010. Mean annual per capita recruitment rates were 0.73 (0.02-2.50) in 2008-2009 and 0.47 (0.02-1.42) in 2009-2010. From 2008 to 2010, the probability of an increase in abundance at this site was 0.873, with an estimated increase of 115 (-82 to 326) individuals. The estimated population growth rate in 2008-2009 was 1.52 (0.73-3.29) and in 2009-2010 was 1.21 (0.70-2.17). Although this population is probably stable or increasing in the short term, long-term studies of the status of the San Francisco gartersnake at other sites are required to estimate population trends and to elucidate mechanisms that promote the recovery of this charismatic member of our native herpetofauna.

  18. 76 FR 19519 - Intent To Prepare an Environmental Impact Statement for the Downtown San Francisco Ferry Terminal...

    Science.gov (United States)

    2011-04-07

    ... Francisco Ferry Terminal Expansion Project in the City and County of San Francisco, CA AGENCY: Federal... Transportation Authority (WETA) are planning to prepare an EIS for the proposed expansion and improvements to the... Expansion Project is to support and expand ferry service on San Francisco Bay, as established by WETA in its...

  19. San Francisco Bay NWR Complex : Annual Narrative Report : Calendar Year 1978

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1978. The report begins with a general...

  20. Physical and chemical properties of San Francisco Bay waters, 1969-1976 (NODC Accession 8400194)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — One magnetic tape containing the physical and chemical properties of San Francisco Bay waters was forwarded to NODC by Mr. Richard Smith of the U.S Geological Survey...

  1. [Don Edwards San Francisco Bay National Wildlife Refuge: Final Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) executive summary was written to guide management on Don Edwards San Francisco National Wildlife Refuge for the next 15...

  2. Stream Habitat Reach Summary - San Francisco Bay, Central Coast [ds159

    Data.gov (United States)

    California Department of Resources — The Stream Habitat - San Francisco Bay, Central and South Coasts [ds159] shapefile contains four years of in-stream salmonid habitat data at the reach level. The...

  3. Reducing Nutrients to San Francisco Bay through Additional Wastewater Sidestream Treatment Project

    Science.gov (United States)

    Information about the SFBWQP Reducing Nutrients to San Francisco Bay Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  4. San Francisco Bay National Wildlife Refuge Complex : Annual Narrative Report : 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1990. The report begins with highlights from the...

  5. San Francisco Bay National Wildlife Refuge Complex : Annual Narrative Report : 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1988. The report begins with highlights from the...

  6. San Francisco Bay National Wildlife Refuge Complex : Annual Narrative Report : 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1986. The report begins with highlights from the...

  7. Annual Narrative Report : San Francisco Bay National Wildlife Refuge Complex : 1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1984. The report begins with highlights from the...

  8. San Francisco Bay National Wildlife Refuge Complex : Annual Narrative Report : 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report details the conditions and management of San Francisco Bay National Wildlife Refuge in 1982. The report begins with highlights from the...

  9. San Francisco Bay ecotone vegetation restoration & management : 2009-10 grant report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a report on vegetation restoration and management at Don Edwards San Francisco Bay National Wildlife Refuge. Restoring vegetation adjacent to the tidal...

  10. San Francisco Estuary Midwinter Waterfowl Survey: 2012 Survey Results and Trend Analysis (1981-2012)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides results of the 2012 San Francisco Estuary Midwinter Waterfowl Survey and presents an analysis of trends in waterfowl counts from 1981-2012. The...

  11. Final Critical Habitat for the San Francisco Peaks groundsel (Senecio franciscanus)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for San Francisco Peaks groundsel (Senecio franciscanus) occur based on the description...

  12. San Francisco Bay ecotone vegetation restoration & management : 2008-09 grant report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a report on vegetation restoration and management at Don Edwards San Francisco Bay National Wildlife Refuge. Vegetation management is often straightforward:...

  13. San Francisco Bay Water Quality Improvement Fund Points, SF Bay CA, 2015, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  14. Public perceptions of the ban on tobacco sales in San Francisco pharmacies.

    Science.gov (United States)

    Kroon, Lisa A; Corelli, Robin L; Roth, Andrew P; Hudmon, Karen Suchanek

    2013-11-01

    In October, 2008, legislation was implemented in the city and county of San Francisco, California, prohibiting the sale of tobacco products in pharmacies. To characterise public awareness and perceptions of the ban on tobacco sales in San Francisco community pharmacies. A brief, anonymous survey was used to assess public awareness and perceptions of a ban on tobacco sales approximately 1 year after implementation. Individuals were approached by researchers outside of chain pharmacies in San Francisco. Smokers and non-smokers were included, and participants did not have to be patrons of the pharmacy. Of 198 participants, 56% were in favor of the ban, 27% opposed it and 17% were undecided. A greater proportion of current tobacco users (81%) than former/never users (48%) were aware of the ban (pshopping behaviour at retail pharmacies. In the city and county of San Francisco, public support exists for prohibiting the sale of tobacco products in pharmacies.

  15. Geology and geomorphology--Offshore of San Francisco Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the geologic and geomorphic map of the Offshore of San Francisco map area, California. The polygon shapefile is included in...

  16. Beneficial Uses of Dredged Material Case Study: San Francisco Bay Region

    Science.gov (United States)

    A major interagency, regional planning effort led to the development of the Long-Term Management Strategy and other planning programs in the San Francisco Bay area. These programs incorporate beneficial uses of dredged material into local projects.

  17. Breeding Season Study of the California Clapper Rail in San Francisco Bay, 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goals of this study were to further investigate the suitability of brackish marshes in south San Francisco Bay to support breeding rails and to examine how the...

  18. Summary of California Clapper Rail winter populations in the San Francisco National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The California Clapper rail (Rallus lonqirostris obsoletus) is a seldom seen resident in some of the remaining tidal salt marshes in San Francisco Bay. The...

  19. Factors affecting reproductive success of the California clapper rail (Rallus longirostris obsoletus) in San Francisco Bay

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We assessed the reproductive success of the California clapper rail (Rallus longirostris obsoletus), an endangered species restricted to San Francisco Bay, and the...

  20. Dioxin toxin equivalents, PCBs, and PBDEs in eggs of avian wildlife of San Francisco Bay

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — San Francisco Bay (Bay) is considered an impaired waterbody under section 303 (d) of the Clean Water Act due to polychlorinated biphenyls (PCB) and 2, 3, 7,...

  1. Don Edwards San Francisco Bay National Wildlife Refuge : Refuge Master Plan : 1974

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Master Plan guides the longrange development of the Refuge by identifying and integrating appropriate habitats,...

  2. Bridging the San Francisco System: 21st Century Strategic Partnerships for the Asian Pacific

    Science.gov (United States)

    2016-04-08

    and Singapore , was established with the purpose of regional cooperation in economic, social, cultural, technical, educational and other fields...COLLEGE JOINT ADVANCED WARFIGHTING SCHOOL BRIDGING THE SAN FRANCISCO SYSTEM : 21st CENTURY STRATEGIC PARTNERSHIPS FOR THE ASIAN-PACIFIC By...the disproportionate security and economic burdens of key bilateral alliances that grew to embody the “San Francisco System .” The United States

  3. EL CONVENTO DE SAN FRANCISCO DE MÉXICO. UN ESTUDIO DE SALUD PÚBLICA

    National Research Council Canada - National Science Library

    Marcela Salas Cuesta

    1996-01-01

    ... de San Francisco de Mexico, año de 1797. La lectura que se puede realizar de éste, pór las mas diversas disciplinas, nos permite tener una amplia concepción de la situacion que guardaba la sociedad novohispana a través de un caso especifico, como es el Convento Grande de San Francisco de México. Palabras clave: ayuntamiento, cabildo, enfermedad, Fra...

  4. EL CONVENTO DE SAN FRANCISCO DE MÉXICO. UN ESTUDIO DE SALUD PÚBLICA

    National Research Council Canada - National Science Library

    Marcela Salas Cuesta; María Elena Salas Cuesta

    1996-01-01

    ... de San Francisco de Mexico, año de 1797. La lectura que se puede realizar de éste, pór las mas diversas disciplinas, nos permite tener una amplia concepción de la situacion que guardaba la sociedad novohispana a través de un caso especifico, como es el Convento Grande de San Francisco de México. Palabras clave: ayuntamiento, cabildo, enfermedad, Frail...

  5. El convento de San Francisco de México: un estudio de salud pública

    National Research Council Canada - National Science Library

    Salas Cuesta, Marcela

    1996-01-01

    ... de San Francisco de Mexico, año de 1797. La lectura que se puede realizar de éste, pór las mas diversas disciplinas, nos permite tener una amplia concepción de la situacion que guardaba la sociedad novohispana a través de un caso especifico, como es el Convento Grande de San Francisco de México. Palabras clave: ayuntamiento, cabildo, enfermedad, Fra...

  6. San Francisco Biofuel Program: Brown Grease to Biodiesel Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Jolis, Domènec [San Francisco Public Utilities Commission, San Francisco, CA (United States); Martis, Mary [San Francisco Public Utilities Commission, San Francisco, CA (United States); Jones, Bonnie [San Francisco Public Utilities Commission, San Francisco, CA (United States); Miot, Alex [San Francisco Public Utilities Commission, San Francisco, CA (United States); Ving, Karri [San Francisco Public Utilities Commission, San Francisco, CA (United States); Sierra, Natalie [San Francisco Public Utilities Commission, San Francisco, CA (United States); Niobi, Morayo [San Francisco Public Utilities Commission, San Francisco, CA (United States)

    2013-03-01

    Municipal wastewater treatment facilities have typically been limited to the role of accepting wastewater, treating it to required levels, and disposing of its treatment residuals. However, a new view is emerging which includes wastewater treatment facilities as regional resource recovery centers. This view is a direct result of increasingly stringent regulations, concerns over energy use, carbon footprint, and worldwide depletion of fossil fuel resources. Resources in wastewater include chemical and thermal energy, as well as nutrients, and water. A waste stream such as residual grease, which concentrates in the drainage from restaurants (referred to as Trap Waste), is a good example of a resource with an energy content that can be recovered for beneficial reuse. If left in wastewater, grease accumulates inside of the wastewater collection system and can lead to increased corrosion and pipe blockages that can cause wastewater overflows. Also, grease in wastewater that arrives at the treatment facility can impair the operation of preliminary treatment equipment and is only partly removed in the primary treatment process. In addition, residual grease increases the demand in treatment materials such as oxygen in the secondary treatment process. When disposed of in landfills, grease is likely to undergo anaerobic decay prior to landfill capping, resulting in the atmospheric release of methane, a greenhouse gas (GHG). This research project was therefore conceptualized and implemented by the San Francisco Public Utilities Commission (SFPUC) to test the feasibility of energy recovery from Trap Waste in the form of Biodiesel or Methane gas.

  7. The San Francisco MSM Epidemic: A Retrospective Analysis

    Directory of Open Access Journals (Sweden)

    Brandy L. Rapatski

    2015-11-01

    Full Text Available We investigate various scenarios for ending the San Francisco MSM (men having sex with men HIV/AIDS epidemic (1978–1984. We use our previously developed model and explore changes due to prevention strategies such as testing, treatment and reduction of the number of contacts. Here we consider a “what-if” scenario, by comparing different treatment strategies, to determine which factor has the greatest impact on reducing the HIV/AIDS epidemic. The factor determining the future of the epidemic is the reproduction number R0; if R0 < 1, the epidemic is stopped. We show that treatment significantly reduces the total number of infected people. We also investigate the effect a reduction in the number of contacts after seven years, when the HIV/AIDS threat became known, would have had in the population. Both reduction of contacts and treatment alone, however, would not have been enough to bring R0 below one; but when combined, we show that the effective R0 becomes less than one, and therefore the epidemic would have been eradicated.

  8. Indoor Air Quality Assessment of the San Francisco Federal Building

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael; Bennett, Deborah H.; Faulkner, David; Maddalena, Randy L.; Russell, Marion L.; Spears, Michael; Sullivan, Douglas P; Trout, Amber L.

    2008-07-01

    An assessment of the indoor air quality (IAQ) of the San Francisco Federal Building (SFFB) was conducted on May 12 and 14, 2009 at the request of the General Services Administration (GSA). The purpose of the assessment was for a general screening of IAQ parameters typically indicative of well functioning building systems. One naturally ventilated space and one mechanically ventilated space were studied. In both zones, the levels of indoor air contaminants, including CO2, CO, particulate matter, volatile organic compounds, and aldehydes, were low, relative to reference exposure levels and air quality standards for comparable office buildings. We found slightly elevated levels of volatile organic compounds (VOCs) including two compounds often found in"green" cleaning products. In addition, we found two industrial solvents at levels higher than typically seen in office buildings, but the levels were not sufficient to be of a health concern. The ventilation rates in the two study spaces were high by any standard. Ventilation rates in the building should be further investigated and adjusted to be in line with the building design. Based on our measurements, we conclude that the IAQ is satisfactory in the zone we tested, but IAQ may need to be re-checked after the ventilation rates have been lowered.

  9. Microbial diversity and carbon cycling in San Francisco Bay wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Theroux, Susanna [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Hartman, Wyatt [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; He, Shaomei [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Univ. of Wisconsin, Madison, WI (United States); Tringe, Susannah [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.

    2014-03-21

    Wetland restoration efforts in San Francisco Bay aim to rebuild habitat for endangered species and provide an effective carbon storage solution, reversing land subsidence caused by a century of industrial and agricultural development. However, the benefits of carbon sequestration may be negated by increased methane production in newly constructed wetlands, making these wetlands net greenhouse gas (GHG) sources to the atmosphere. We investigated the effects of wetland restoration on below-ground microbial communities responsible for GHG cycling in a suite of historic and restored wetlands in SF Bay. Using DNA and RNA sequencing, coupled with real-time GHG monitoring, we profiled the diversity and metabolic potential of wetland soil microbial communities. The wetland soils harbor diverse communities of bacteria and archaea whose membership varies with sampling location, proximity to plant roots and sampling depth. Our results also highlight the dramatic differences in GHG production between historic and restored wetlands and allow us to link microbial community composition and GHG cycling with key environmental variables including salinity, soil carbon and plant species.

  10. Edificio para ambulatorio San Francisco – (EE. UU.

    Directory of Open Access Journals (Sweden)

    Reid, John Lyon

    1976-12-01

    Full Text Available The 50,470 m2 the total area of the hospital is distributed as follows: 18,900 m2 for the 22 main clinics and for the additional clinics; 2,770 m2 for complementary activities; and the remaining 28,800 m2 for a parking lot with space for 700 cars. The building occupies a site that slopes strongly towards the north across which runs the pedestrian access from one of the circumference roads to the main façade; the access road for the vehicles leads to the back facade, where the natural slope of the ground has been taken advantage of to build the 5 storey parking building. The two main functions —the clinics and the parking house— are conveniently separated though connected with each other by means of corridors and lifts. The interior design of the clinics is very flexible so as to allow for further enlargements. The patients' waiting rooms are provided with a glazed façade and have a beautiful view over the San Francisco Bay and its surroundings. The construction is entirely of concrete and its structure is calculated ín such a manner as to allow for two additional storeys.Cuenta con una superficie total construida de 50.470 m2, repartidos de la siguiente forma: 18.900 se destinan a la distribución de 22 clínicas principales y otras secundarias; 2.770 a locales de actividades complementarias; y el resto, 28.800 m2, a aparcamiento con capacidad para 700 plazas. El edificio ocupa una parcela fuertemente inclinada hacia el norte, inclinación que permite el acceso peatonal a la clínica, por la fachada principal, desde una de las avenidas perimetrales; y el vehicular, por la fachada posterior, en donde, aprovechando el desnivel del terreno, se han organizado las cinco plantas del aparcamiento. Las dos funciones principales —clínicas y aparcamiento— se hallan convenientemente separadas, estableciéndose el enlace entre los distintos niveles mediante ascensores que relacionan las clínicas, el centro médico, los aparcamientos

  11. Discovery Along the San Andreas Fault: Relocating Photographs From the 1906 Earthquake in San Francisco and San Mateo Counties

    Science.gov (United States)

    Grove, K.; Prentice, C.; Polly, J.; Yuen, C.; Wu, K.; Zhong, S.; Lopez, J.

    2005-12-01

    April of 2006 will mark the 100-year anniversary of the great 1906 San Francisco earthquake. This earthquake was important not only because of its human tragedy (thousands of dead or homeless people), but also because of its scientific significance. The 8.3 magnitude earthquake ruptured 430 km of the northern San Andreas fault (SAF) and lasted nearly one minute. Investigations after the earthquake led to discoveries that were the beginning of modern earthquake theories and measuring instruments. This was also one of the first large-scale natural disasters to be photographed. Our research group, which is part of the National Science Foundation funded SF-ROCKS program, acquired photographs that were taken shortly after the earthquake in downtown San Francisco and along the SAF in San Mateo County. The SAF photos are part of a Geographical Information System (GIS) database being published on a U.S. Geological Survey web site. The goal of our project was to improve estimates of photograph locations and to compare the landscape features that were visible after the earthquake with the landscape that we see today. We used the GIS database to find initial photo locations, and we then used a high-precision Global Positioning System (GPS) to measure the geographic coordinates of the locations once we matched our view to what we saw in a photo. Where possible, we used a digital camera to retake photos from the same position, to show the difference in the landscape 100 years later. The 1906 photos show fault zone features such as ground rupture, sag ponds, shutter ridges, and offset fences. Changes to the landscape since 1906 have included erosion and grading of the land, building of houses and other structures, and more tree cover compared to previous grassland vegetation. Our project is part of 1906 Earthquake Centennial activities; it is contributing to the photo archive that helps scientists and engineers who study earthquakes and their effects. It will also help the

  12. Phytoplankton community ecology: Principles applied in San Francisco Bay

    Science.gov (United States)

    Cloern, J.E.; Dufford, R.

    2005-01-01

    In his seminal 1961 paper 'The paradox of the plankton' Am Nat 95:137-147, G. E. Hutchinson asked why many species of phytoplankton can coexist while competing for a small number of limiting resources in an unstructured habitat. Hutchinson anticipated the resolution of his paradox, recognizing that communities are organized by processes beyond resource competition including species interactions, habitat variability and dispersal. Since 1961 we have made fundamental discoveries that have revolutionized our conceptual understanding of pelagic ecology, including (1) habitat heterogeneity at all scales relevant to plankton population dynamics, (2) community shifts in response to global climate cycles, (3) fast and selective predation as a powerful top-down force to shape phytoplankton communities, (4) turbulent mixing as a physical process that selects species on the basis of their size and form, (5) mixotrophy that allows some algal species to tap organic nutrient pools and function at multiple trophic levels, (6) taxon-specific life cycles including alternating vegetative and resting stages, and (7) the pelagic as an open system where communities are continually reshaped by species immigration. Here we synthesize these discoveries to show how they validate and amplify Hutchinson's hypothesis that phytoplankton communities are assembled by many processes. Our synthesis is built around observations of phytoplankton species composition from a decade of study in San Francisco Bay, used as a case study to illustrate the contemporary principles of phytoplankton community ecology. We apply these principles to address 2 central questions: (1) What processes assemble phytoplankton communities? (2) How does phytoplankton community composition influence ecosystem functions such as production in pelagic and benthic food webs?

  13. A summary of the San Francisco tidal wetlands restoration series

    Directory of Open Access Journals (Sweden)

    Larry R. Brown

    2003-10-01

    Full Text Available The four topical articles of the Tidal Wetlands Restoration Series summarized and synthesized much of what is known about tidal wetlands and tidal wetland restoration in the San Francisco Estuary (hereafter “Estuary”. Despite a substantial amount of available information, major uncertainties remain. A major uncertainty with regard to fishes is the net benefit of restored tidal wetlands relative to other habitats for native fishes in different regions of the Estuary given the presence of numerous invasive alien species. With regard to organic carbon, a major uncertainty is the net benefit of land use change given uncertainty about the quantity and quality of different forms of organic carbon resulting from different land uses. A major challenge is determining the flux of organic carbon from open systems like tidal wetlands. Converting present land uses to tidal wetlands will almost certainly result in increased methylation of mercury at the local scale with associated accumulation of mercury within local food webs. However, it is unclear if such local accumulation is of concern for fish, wildlife or humans at the local scale or if cumulative effects at the regional scale will emerge. Based on available information it is expected that restored tidal wetlands will remain stable once constructed; however, there is uncertainty associated with the available data regarding the balance of sediment accretion, sea-level rise, and sediment erosion. There is also uncertainty regarding the cumulative effect of many tidal restoration projects on sediment supply. The conclusions of the articles highlight the need to adopt a regional and multidisciplinary approach to tidal wetland restoration in the Estuary. The Science Program of the CALFED effort provides an appropriate venue for addressing these issues.

  14. Regional Air Toxics Modeling in California's San Francisco Bay Area

    Science.gov (United States)

    Martien, P. T.; Tanrikulu, S.; Tran, C.; Fairley, D.; Jia, Y.; Fanai, A.; Reid, S.; Yarwood, G.; Emery, C.

    2011-12-01

    Regional toxics modeling conducted for California's San Francisco Bay Area (SFBA) estimated potential cancer risk from diesel particulate matter (DPM) and four key reactive toxic gaseous pollutants (1,3-butadiene, benzene, formaldehyde, and acetaldehyde). Concentrations of other non-cancerous gaseous toxic air contaminants, including acrolein, were also generated. In this study, meteorological fields generated from July and December periods in 2000 and emissions from 2005 provided inputs to a three-dimensional air quality model at high spatial resolution (1x1 km^2 grid), from which a baseline set of annual risk values was estimated. Simulated risk maps show highest annual average DPM concentrations and cancer risks were located near and downwind of major freeways and near the Port of Oakland, a major container port in the area. Population weighted risks, using 2000 census data, were found to be highest in highly urbanized areas adjacent to significant DPM sources. For summer, the ratio of mean measured elemental carbon to mean modeled DPM was 0.78, conforming roughly to expectations. But for winter the ratio is 1.13, suggesting other sources of elemental carbon, such as wood smoke, are important. Simulated annual estimates for benzene and 1-3, butadiene compared well to measured annual estimates. Simulated acrolein and formaldehyde significantly under-predicted observed values. Simulations repeated using projected 2015 toxic emissions predicted that potential cancer risk dropped significantly in all areas throughout the SFBA. Emissions estimates for 2015 included the State of California's recently adopted on-road truck rule. Emission estimates of DPM are projected to drop about 70% between 2005 and 2015 in the SFBA, with a commensurate reduction in potential cancer risks. However, due to projected shifts in population during this period, with urban densification close to DPM sources outpacing emission reductions, there are some areas where population-weighted risks

  15. Psychiatric Disorders and Substance Use in Homeless Youth: A Preliminary Comparison of San Francisco and Chicago

    Directory of Open Access Journals (Sweden)

    Ernika G. Quimby

    2012-08-01

    Full Text Available Youth homelessness is a growing problem in the United States. The experience of homelessness appears to have numerous adverse consequences, including psychiatric and substance use disorders. This study compared the frequencies of psychiatric disorders, including substance use, between homeless youth (18–24 years-old in San Francisco (N = 31 and Chicago (N = 56. Subjects were administered the Mini International Neuropsychiatric Interview (M.I.N.I. to assess DSM-IV-TR diagnoses and substance use disorders. Eighty-seven percent of the San Francisco youth, and 81% of the Chicago youth met criteria for at least one M.I.N.I. psychiatric diagnosis. Nearly two-thirds of the youth in both samples met criteria for a mood disorder. Approximately one-third met criteria for an anxiety disorder. Thirty-two percent of the San Francisco sample and 18% of the Chicago met criteria for Antisocial Personality Disorder. Approximately 84% of the San Francisco youth and 48% of the Chicago youth met criteria for a substance-related disorder, and more substances were used by San Francisco youth. In conclusion, the high rate of psychiatric disorders in homeless youth provides clear evidence that the mental health needs of this population are significant. Implications are discussed.

  16. Constraints on the sedimentation history of San Francisco Bay from 14C and 10Be

    Science.gov (United States)

    VanGeen, A.; Valette-Silver, N. J.; Luoma, S.N.; Fuller, C.C.; Baskaran, M.; Tera, F.; Klein, J.

    1999-01-01

    Industrialization and urbanization around San Francisco Bay as well as mining and agriculture in the watersheds of the Sacramento and San Joaquin rivers have profoundly modified sedimentation patterns throughout the estuary. We provide some constraints on the onset of these erosional disturbances with 10Be data for three sediment cores: two from Richardson Bay, a small embayment near the mouth of San Francisco Bay, and one from San Pablo Bay, mid-way between the river delta and the mouth. Comparison of pre-disturbance sediment accumulation determined from three 14C-dated mollusk shells in one Richardson Bay core with more recent conditions determined from the distribution of 210Pb and 234Th [Fuller, C.C., van Geen, A., Baskaran, M, Anima, R.J., 1999. Sediment chronology in San Francisco Bay, California, defined by 210Pb, 234Th, 239,240Pu.] shows that the accumulation rate increased by an order of magnitude at this particular site. All three cores from San Francisco Bay show subsurface maxima in 10Be concentrations ranging in magnitude from 170 to 520 x 106 atoms/g. The transient nature of the increased 10Be input suggests that deforestation and agricultural develop- ment caused basin-wide erosion of surface soils enriched in 10Be. probably before the turn of the century.

  17. Cannabis policies and user practices: market separation, price, potency, and accessibility in Amsterdam and San Francisco.

    Science.gov (United States)

    Reinarman, Craig

    2009-01-01

    This paper explores user perceptions and practices in contrasting legal-policy milieux-Amsterdam (de facto decriminalization) and San Francisco (de jure criminalization) on four policy issues: sources of cannabis and separation of markets for it and other drugs; user perceptions of effects of price on consumption; effects of potency on consumption; and perceived risk of arrest and accessibility of cannabis. Questions on these issues were added to surveys on career use patterns amongst representative samples of experienced cannabis users using comparable methods. Most San Francisco respondents obtained cannabis through friends who knew dealers, whereas most Amsterdam respondents obtained it from regulated shops. Only one in seven Amsterdam respondents but half the San Francisco respondents could obtain other drugs from their cannabis sources. Majorities under both systems had never found cannabis "too expensive." Amsterdam respondents preferred milder cannabis whilst San Francisco respondents preferred stronger; majorities in both cities reported self-titrating with potent cannabis. Risk and fear of arrest were higher in San Francisco, but most in both cities perceived arrest as unlikely. Estimated search times were somewhat longer in San Francisco, but a majority reported being able to access it within half a day. There is substantial separation of markets in the Dutch system. Policies designed to increase cannabis prices appear unlikely to impact consumption. Decriminalization was associated with a preference for milder cannabis, but under both policy regimes most respondents self-titrated when using more potent strains. Criminalization was associated with somewhat higher risk and fear of arrest and somewhat longer search times, but these did not appear to significantly impede access for most respondents.

  18. Chronic Sublethal Effects of San Francisco Bay Sediments on Nereis (Neanthes) arenaceodentata; Interpretative Guidance for a Growth End Point

    Science.gov (United States)

    1993-09-01

    experimentally. Once nereid eggs begin developing in the coelom , secretion of a separate tropic hormone initiates vitellogenesis (Baskin 1976). In N...Material Management in San Francisco Bay .............................. 2 Overview of Sediment Toxicity Test Development in the United States...Material in San Francisco Bay ......................... 3 Table 2. Milestones in Scientific Development of Sediment Toxicity Tests

  19. U.S. EPA and San Francisco Department of the Environment Spotlight Super Bowl Efforts to Feed the Hungry

    Science.gov (United States)

    SAN FRANCISCO - On Wednesday, February 3, U.S. EPA Regional Administrator Jared Blumenfeld will be joined by San Francisco Department of the Environment Director Debbie Raphael, Food Runners Director Mary Risley, and HealthRIGHT 360 CEO Vitka Eisen to dis

  20. San Francisco 's Golden Gate: A bridge between historically distinct coyote (Canis latrans) populations?

    Science.gov (United States)

    Sacks, Benjamin N.; Ernest, Holly B.; Boydston, Erin E.

    2006-01-01

    Although coyotes (Canis latrans) are wellknown for their adaptability to human-modified landscapes (Riley et al. 2003), as with any medium to large-sized carnivore, they typically avoid highly urbanized areas (Crooks 2002), preferring instead to use habitat fragments linked by vegetated corridors (Tigas et al. 2002). However, recent observations of coyotes in San Francisco indicate their willingness to traverse even the most densely urbanized terrain (Rubenstein 2003). Herein we use DNA to show, in an extreme example, that an adult male coyote caught in the northern tip of the San Francisco peninsula traversed the 2-km Golden Gate Bridge, potentially linking historically distinct coyote populations.

  1. Epidemiology of Mycobacterium tuberculosis strains in San Francisco that do not contain IS6110.

    Science.gov (United States)

    Agasino, C B; Ponce de Leon, A; Jasmer, R M; Small, P M

    1998-06-01

    IS6110 is commonly used as the basis for molecular epidemiologic and diagnostic studies of Mycobacterium tuberculosis. However, strains that do not contain IS6110 have been reported. If common, such strains would pose a limitation for molecular studies of M. tuberculosis. Analysis of a population-based sample from San Francisco of 1569 specimens submitted for fingerprinting demonstrated that the proportion of strains that lack IS6110 is less than 1%. While this low percentage permits IS6110 fingerprinting in San Francisco, it may be problematic in other settings.

  2. La lectura bonaventuriana de Aristóteles desde san Francisco

    Directory of Open Access Journals (Sweden)

    Manuel Lázaro Pulido

    2017-05-01

    Full Text Available Parece una obviedad señalar la importancia de san Francisco en el pensamiento de la Escuela Franciscana. No obstante cuando hablamos de la lectura agustinista de los filósofos y de los teólogos franciscanos establecemos una dicotomía entre aristotelismo y agustinismo en la que se nos olvida con frecuencia la figura de san Francisco de Asís. Queremos señalar la impronta de la teología sanfranciscana en la interpretación agustinista de la naturaleza como complemento a la lectura que Buenaventura realiza de Aristóteles.

  3. Anthropogenic influences on shoreline and nearshore evolution in the San Francisco Bay coastal system

    Science.gov (United States)

    Dallas, K.L.; Barnard, P.L.

    2011-01-01

    Analysis of four historical bathymetric surveys over a 132-year period has revealed significant changes to the morphology of the San Francisco Bar, an ebb-tidal delta at the mouth of San Francisco Bay estuary. From 1873 to 2005 the San Francisco Bar vertically-eroded an average of 80 cm over a 125 km2 area, which equates to a total volume loss of 100 ± 52 million m3 of fine- to coarse-grained sand. Comparison of the surveys indicates the entire ebb-tidal delta contracted radially, with the crest moving landward an average of 1 km. Long-term erosion of the ebb-tidal delta is hypothesized to be due to a reduction in the tidal prism of San Francisco Bay and a decrease in coastal sediment supply, both as a result of anthropogenic activities. Prior research indicates that the tidal prism of the estuary was reduced by 9% from filling, diking, and sedimentation. Compilation of historical records dating back to 1900 reveals that a minimum of 200 million m3 of sediment has been permanently removed from the San Francisco Bay coastal system through dredging, aggregate mining, and borrow pit mining. Of this total, ~54 million m3 of sand-sized or coarser sediment was removed from central San Francisco Bay. With grain sizes comparable to the ebb-tidal delta, and its direct connection to the bay mouth, removal of sediments from central San Francisco Bay may limit the sand supply to the delta and open coast beaches. SWAN wave modeling illustrates that changes to the morphology of the San Francisco Bar have altered the alongshore wave energy distribution at adjacent Ocean Beach, and thus may be a significant factor in a persistent beach erosion ‘hot spot’ occurring in the area. Shoreline change analyses show that the sandy shoreline in the shadow of the ebb-tidal delta experienced long-term (1850s/1890s to 2002) and short-term (1960s/1980s to 2002) accretion while the adjacent sandy shoreline exposed to open-ocean waves experienced long-term and short-term erosion. Therefore

  4. Climate Change and Conservation Planning in California: The San Francisco Bay Area Upland Habitat Goals Approach

    Science.gov (United States)

    Branciforte, R.; Weiss, S. B.; Schaefer, N.

    2008-12-01

    Climate change threatens California's vast and unique biodiversity. The Bay Area Upland Habitat Goals is a comprehensive regional biodiversity assessment of the 9 counties surrounding San Francisco Bay, and is designing conservation land networks that will serve to protect, manage, and restore that biodiversity. Conservation goals for vegetation, rare plants, mammals, birds, fish, amphibians, reptiles, and invertebrates are set, and those goals are met using the optimization algorithm MARXAN. Climate change issues are being considered in the assessment and network design in several ways. The high spatial variability at mesoclimatic and topoclimatic scales in California creates high local biodiversity, and provides some degree of local resiliency to macroclimatic change. Mesoclimatic variability from 800 m scale PRISM climatic norms is used to assess "mesoclimate spaces" in distinct mountain ranges, so that high mesoclimatic variability, especially local extremes that likely support range limits of species and potential climatic refugia, can be captured in the network. Quantitative measures of network resiliency to climate change include the spatial range of key temperature and precipitation variables within planning units. Topoclimatic variability provides a finer-grained spatial patterning. Downscaling to the topoclimatic scale (10-50 m scale) includes modeling solar radiation across DEMs for predicting maximum temperature differentials, and topographic position indices for modeling minimum temperature differentials. PRISM data are also used to differentiate grasslands into distinct warm and cool types. The overall conservation strategy includes local and regional connectivity so that range shifts can be accommodated.

  5. Probabilistic estimation of numbers and costs of future landslides in the San Francisco Bay region

    Science.gov (United States)

    Crovelli, R.A.; Coe, J.A.

    2009-01-01

    We used historical records of damaging landslides triggered by rainstorms and a newly developed Probabilistic Landslide Assessment Cost Estimation System (PLACES) to estimate the numbers and direct costs of future landslides in the 10-county San Francisco Bay region. Historical records of damaging landslides in the region are incomplete. Therefore, our estimates of numbers and costs of future landslides are minimal estimates. The estimated mean annual number of future damaging landslides for the entire 10-county region is about 65. Santa Cruz County has the highest estimated mean annual number of damaging future landslides (about 18), whereas Napa, San Francisco, and Solano Counties have the lowest estimated mean numbers of damaging landslides (about 1 each). The estimated mean annual cost of future landslides in the entire region is about US $14.80 million (year 2000 $). The estimated mean annual cost is highest for San Mateo County ($3.24 million) and lowest for Solano County ($0.18 million). The annual per capita cost for the entire region will be about $2.10. Santa Cruz County will have the highest annual per capita cost at $8.45, whereas San Francisco County will have the lowest per capita cost at $0.31. Normalising costs by dividing by the percentage of land area with slopes equal to or greater than 17% indicates that San Francisco County will have the highest cost per square km ($7,101), whereas Santa Clara County will have the lowest cost per square km ($229). These results indicate that the San Francisco Bay region has one of the highest levels of landslide risk in the United States. Compared with landslide cost estimates from the rest of the world, the risk level in the Bay region seems high, but not exceptionally high.

  6. Delineating incised stream sediment sources within a San Francisco Bay tributary basin

    Science.gov (United States)

    Bigelow, Paul; Benda, Lee; Pearce, Sarah

    2016-07-01

    Erosion and sedimentation pose ubiquitous problems for land and watershed managers, requiring delineation of sediment sources and sinks across landscapes. However, the technical complexity of many spatially explicit erosion models precludes their use by practitioners. To address this critical gap, we demonstrate a contemporary use of applied geomorphometry through a straightforward GIS analysis of sediment sources in the San Francisco Bay Area in California, USA, designed to support erosion reduction strategies. Using 2 m lidar digital elevation models, we delineated the entire river network in the Arroyo Mocho watershed (573 km2) at the scale of ˜ 30 m segments and identified incised landforms using a combination of hillslope gradient and planform curvature. Chronic erosion to the channel network was estimated based on these topographic attributes and the size of vegetation, and calibrated to sediment gage data, providing a spatially explicit estimate of sediment yield from incised channels across the basin. Rates of erosion were summarized downstream through the channel network, revealing patterns of sediment supply at the reach scale. Erosion and sediment supply were also aggregated to subbasins, allowing comparative analyses at the scale of tributaries. The erosion patterns delineated using this approach provide land use planners with a robust framework to design erosion reduction strategies. More broadly, the study demonstrates a modern analysis of important geomorphic processes affected by land use that is easily applied by agencies to solve common problems in watersheds, improving the integration between science and environmental management.

  7. Time scales of change in the San Francisco Bay benthos

    Science.gov (United States)

    Nichols, F.H.; Thompson, J.K.

    1985-01-01

    Results from multi-year investigations in the San Francisco Bay estuary show that large abundance fluctuations within benthic macroinvertebrate populations reflect both (1) within-year periodicity of reproduction, recruitment, and mortality that is not necessarily coincident with seasonal changes of the environment (e.g., the annual temperature cycle), and (2) aperiodic density changes (often larger than within-year fluctuations) following random perturbations of the environment. Density peaks of the small, short-lived estuarine invertebrates that comprise the vast majority of individuals in the bay's relatively homogeneous benthic community normally occur between spring and autumn depending on the species, in large part a reflection of reproductive periodicity. However, because mild winters permit reproductive activity in some of the common species throughout much of the year, other factors are important to within-year density fluctuations in the community. Seasonally predictable changes in freshwater inflow, wind and tidal mixing, microalgal biomass, and sediment erosion/deposition patterns all contribute to observed seasonal changes in abundance. For example, the commonly observed decline in abundance during winter reflects both short-lived species that die after reproducing and the stress of winter conditions (e.g., inundation by less saline, sediment-laden water and the decline in both planktonic and benthic algal biomass - a direct source of food for the shallow-water benthos). On the other hand, data from several studies suggest that observed 'recruitment' and 'mortality' may in fact be the migration of juveniles and adults to and from study sites. For example, the common amphipod Ampelisca abdita apparently moves from shallow to deep water, or from up-estuary to down-estuary locations, coincident with periods of high river runoff in winter. Growth of individuals within the few studied species populations is also highly seasonal, and appears to be coincident

  8. The State of Latino Education in the San Francisco Bay Area: A Crisis in Student Performance.

    Science.gov (United States)

    Chacon, Mario

    A study examined educational attainment among Latino students in the six-county San Francisco Bay Area. California's Standardized Testing and Reporting (STAR) Program results for 1998-99 were used to assess student achievement in reading and mathematics for grades 4, 7, and 10. Data were also collected on enrollment, dropout rates, percentage of…

  9. Kokes Awards for the 21st NAM Meeting (San Francisco, CA, 2009)

    Energy Technology Data Exchange (ETDEWEB)

    Katz, Alex [Univ. of California, Berkeley, CA (United States)

    2009-08-31

    The PI in this project Alexander Katz, UC Berkeley (askatz@berkeley.edu), in conjunction with the Kokes Awards subcommittee and conference organizing committee, used DOE grant DE-FG-02-08ER15993 to partially offset costs of attending the 21st North American Catalysis Society in San Francisco, California, for 30 graduate students from the United States.

  10. EPA Administrator and San Francisco Bay Area government agencies celebrate nations largest solar energy partnership

    Science.gov (United States)

    SAN FRANCISCO - Today, U.S. EPA Administrator Gina McCarthy joined Bay Area agencies to celebrate the Regional Renewable Energy Procurement Project (R-REP), the nation's largest solar energy government collaboration and the launch of the Federal Agg

  11. Travel and Tourism Industry: Program Options for City College of San Francisco.

    Science.gov (United States)

    City Coll. of San Francisco, CA.

    In an effort to determine the current occupational outlook and resulting implications for education and training, the City College of San Francisco (CCSF), in California, undertook a study of current trends in the travel and tourism industry. This report provides findings from the project, which involved consultation with local and national…

  12. A nowcast model for tides and tidal currents in San Francisco Bay, California

    Science.gov (United States)

    Cheng, Ralph T.; Smith, Richard E.

    1998-01-01

    National Oceanographic and Atmospheric Administration (NOAA) installed Physical Oceanographic Real-Time System (PORTS) in San Francisco Bay, California to provide observations of tides, tidal currents, and meteorological conditions. PORTS data are used for optimizing vessel operations, increasing margin of safety for navigation, and guiding hazardous material spill prevention and response. Because tides and tidal currents in San Francisco Bay are extremely complex, limited real-time observations are insufficient to provide spatial resolution for variations of tides and tidal currents. To fill the information gaps, a highresolution, robust, semi-implicit, finite-difference nowcast numerical model has been implemented for San Francisco Bay. The model grid and water depths are defined on coordinates based on Mercator projection so the model outputs can be directly superimposed on navigation charts. A data assimilation algorithm has been established to derive the boundary conditions for model simulations. The nowcast model is executed every hour continuously for tides and tidal currents starting from 24 hours before the present time (now) covering a total of 48 hours simulation. Forty-eight hours of nowcast model results are available to the public at all times through the World Wide Web (WWW). Users can view and download the nowcast model results for tides and tidal current distributions in San Francisco Bay for their specific applications and for further analysis.

  13. Who Guards the Guardians? National Implications of Accreditation at City College of San Francisco

    Science.gov (United States)

    Barber, Bob; McNair, Delores E.

    2017-01-01

    Purpose: This article addresses the broad context of community college accreditation which surrounds a controversy involving one of the largest community colleges in the United States, City College of San Francisco (CCSF), and its regional accrediting agency, the Accrediting Commission for Community and Junior Colleges (ACCJC). Its purposes are to…

  14. CAREER TRAINING IN HOTEL AND RESTAURANT OPERATION...AT CITY COLLEGE OF SAN FRANCISCO.

    Science.gov (United States)

    BATMALE, LOUIS F.; MULLANY, GEORGE G.

    THE HOTEL AND RESTAURANT PROGRAM, ONE OF 35 SEMIPROFESSIONAL TRAINING PROGRAMS AT CITY COLLEGE OF SAN FRANCISCO, COMBINES GENERAL EDUCATION, RELATED BUSINESS INSTRUCTION, HOTEL AND RESTAURANT CLASSES, FOOD PREPARATION AND SERVICE TRAINING, AND WORK EXPERIENCE. THIS DESCRIPTION OF THE PROGRAM INCLUDES (1) PURPOSES AND OBJECTIVES, (2) CURRICULUM,…

  15. 75 FR 19882 - Safety Zone; Benchmark Destination Corporate Party, Fireworks Display, San Francisco, CA

    Science.gov (United States)

    2010-04-16

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Benchmark Destination Corporate Party... support of the Benchmark Destination Corporate Party Fireworks Display. This safety zone is being... City of San Francisco will sponsor the Benchmark Destinations Corporate Party Fireworks Display on July...

  16. Modeling Sulfides, pH and Hydrogen Sulfide Gas in the Sewers of San Francisco

    DEFF Research Database (Denmark)

    Vollertsen, Jes; Revilla, Nohemy; Hvitved-Jacobsen, Thorkild

    2015-01-01

    An extensive measuring campaign targeted on sewer odor problems was undertaken in San Francisco. It was assessed whether a conceptual sewer process model could reproduce the measured concentrations of total sulfide in the wastewater and H2S gas in the sewer atmosphere, and to which degree such si...

  17. The Varieties of Religious Experience: Baptized Indians at Mission San Francisco de Asis, 1776-1821

    Science.gov (United States)

    Newell, Quincy D.

    2008-01-01

    Paseos, which are defined as trips away from the mission authorized by the Franciscan priests, were common among Indians baptized at Mission San Francisco during the period between 1700s to 1800s. Indians went on these journeys in order to harvest acorns and other wild foods, to hunt and fish, and to visit friends and family outside the mission.…

  18. Preparing for Prison: Life in San Francisco's Inner-City Neighborhoods. Draft.

    Science.gov (United States)

    Feldman, Harvey W.; And Others

    A study of inner-city youth in San Francisco (California) shows that behavior and street ideology once associated exclusively with gangs have now become the world view of a large segment of inner-city young people, especially males. Inner-city young people who aspire to material success do not see a realistic connection between public education…

  19. Incidence of anal cancer in California: increased incidence among men in San Francisco, 1973-1999.

    Science.gov (United States)

    Cress, Rosemary D; Holly, Elizabeth A

    2003-05-01

    Incidence of anal cancer has increased in the United States during the past 30 years. This report describes the incidence of this rare cancer in the diverse California population. Age-adjusted incidence rates (AAIR) were calculated by gender, race/ethnicity, county, and year of diagnosis for over 2100 cases of cancer of the anus diagnosed between 1995 and 1999. Age-adjusted incidence rates by time period 1973-1999 were calculated for San Francisco County. Age-adjusted incidence was higher for women than for men (AAIR 1.5 vs 1.2) in California, but men under age 40 and those classified as non-Hispanic Black had higher rates than women, and men had higher rates in San Francisco County (AAIR=8.7). Rates were higher among non-Hispanic Blacks and Whites than among Hispanics and Asian/Pacific Islanders. For all of California, there was an average 2% annual increase among non-Hispanic White men between 1988 and 1999. Incidence of this cancer among White males residing in San Francisco County more than doubled between the 1984-1990 and 1996-1999 time periods. Rates rose especially dramatically for San Francisco men ages 40 to 64, from 3.7 cases per 100,000 in 1973-1978 to 8.6 cases per 100,000 in 1984-1990 and to 20.6 cases per 100,000 in 1996-1999. Elevated incidence of anal cancer among White men residing in San Francisco County is likely to be related to the high proportion of men who have sex with men. Rates of anal cancer in this high-risk population increased during the past decade.

  20. Hydrostratigraphy of the Westside Groundwater Basin, San Francisco and San Mateo Counties, California

    Science.gov (United States)

    Rogge, E. H.; Laforce, M. J.

    2002-12-01

    The Westside Groundwater Basin is a coastal aquifer system located on the San Francisco Peninsula between Golden Gate Park and Burlingame. Since the beginning of the 20th century groundwater from the Basin has been used for drinking water and irrigation purposes. Unfortunately, the Basin wide potentiometric surface has gradually declined and saltwater intrusion from the Pacific Ocean is threatening this fragile aquifer system. Several studies have looked at groundwater movement within the Basin (Boone, Cook and Associates (1987), Yates et al. (1990), Applied Consultants (1991), Geo/Resources Consultants (1993), Phillips et al. (1993), CH2Mhill (1997)); unfortunately, all of the studies assumed horizontal layering of the hydrostratigraphic units. However, recent studies indicate that tectonic deformation and intense folding has altered the stratigraphy of the Westside Basin close to the Pacific Ocean (Bonilla (1998), Barr (1999)). Accordingly, the purpose of this study is to delineate hydrostratigraphic units within the Westside Basin by using tritium, helium, and oxygen isotopes in conjunction with general mineral water quality data, water level data, and geologic cross-sections to depict the subsurface hydrogeology of the system. Our results indicate that the upper part of the Merced Formation (sequences P through Z of Clifton and Hunter (1991, 1999)) forms the major hydrostratigraphic units where groundwater is extracted, and that the Serra Fault separates the upper part of the Merced from the lower part (below sequence P) along most of its extent. In addition, thick clay layers, observed in well logs and identified in cross sections, were tentatively correlated with sequences W and S2. These clay layers, although discontinuous at places, work as aquitards between the hydrostratigraphic units as the difference in water chemistry and age indicates.

  1. Environmental Sensitivity Index (ESI) Atlas: San Francisco Bay - 1998, maps and geographic information systems data (NODC Accession 0036884)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) maps for the shoreline of San Francisco Bay. ESI data characterize estuarine environments and...

  2. Uudised : Neeme Järvi San Franciscos. Tõnis Mägi Moskvas. TMKK Norras ja Ungaris / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2000-01-01

    N. Järvi juhatab San Francisco Ooperis Rimski-Korsakovi ooperit "Tsaari mõrsja", esietendus 11. sept. T. Mägi esines 1. sept. Eesti Suursaatkonnas Moskvas. TMKK Kammerkoori kontsertreisidest Norrasse ja Ungarisse

  3. Effects of waterborne lipophilic contaminants in striped bass using extracts from semi permeable membrane devices in the San Francisco estuary

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The decline of pelagic organisms in the San Francisco Estuary (SFE) has been attributed to several factors including water diversions, invasive species and exposure...

  4. DISTRIBUTION AND COMPOSITION OF DISSOLVED AND PARTICULATE ORGANIC CARBON IN NORTHERN SAN FRANCISCO BAY DURING LOW FRESHWATER FLOW CONDITIONS

    Science.gov (United States)

    The distribution of organic matter was studied in northern San Francisco Bay monthly through spring and summer 1996 along the salinity gradient from the Sacramento River to Central Bay. Dissolved constituents included monosaccharides (MONO), total carbohydrates (TCHO), dissolved ...

  5. U.S. EPA honors San Francisco Bay Area firm Hybrid Coating Technologies with Green Chemistry Award

    Science.gov (United States)

    SAN FRANCISCO - Today the U.S. Environmental Protection Agency recognized Hybrid Coating Technologies of Daly City, Calif. with a Presidential Green Chemistry Award for developing a safer, plant-based polyurethane for use on floors, furniture and in

  6. Environmental Sensitivity Index (ESI) Atlas: San Francisco Bay, California maps and geographic information systems data (NODC Accession 0013224)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set comprises the Environmental Sensitivity Index (ESI) maps for the shoreline of San Francisco Bay. ESI data characterize estuarine environments and...

  7. Air Quality Benefits of Ship Fuel Regulations in the San Francisco Bay Area

    Science.gov (United States)

    Tao, L.; Harley, R. A.; Fairley, D.; Martien, P. T.

    2012-12-01

    Ocean-going vessels burning high-sulfur heavy fuel oil are an important emission source of air pollutants such as sulfur dioxide and particulate matter. Beginning July 1, 2009, an emission control area was put into effect at ports and along the California coastline, requiring use of low-sulfur marine fuels in place of heavy fuel oil in main engines of ships. To assess impacts of the fuel changes on air quality at the Port of Oakland and in the surrounding San Francisco Bay area, we analyzed speciated fine particle composition data from 4 urban sites and 2 more remote sites (Point Reyes and Pinnacles) from the IMPROVE network. Measured changes in concentrations of vanadium, a useful and specific tracer for heavy fuel oil combustion, are related to overall changes in primary aerosol emissions from ships. The results indicate a substantial reduction in vanadium concentrations after the fuel change, and a 13 to 38% decrease in SO2 concentration, with the SO2 decrease varying depending on proximity to shipping lanes. We inferred from emission factors documented in the literature that marine vessel contributions to primary fine particulate matter mass in the Bay Area, prior to the fuel change, were on the order of 1 to 5%.

  8. Modeling Magnetic Fields from a DC Power Cable Buried Beneath San Francisco Bay Based on Empirical Measurements

    OpenAIRE

    Kavet, Robert; Wyman, Megan T.; Klimley, A. Peter

    2016-01-01

    The Trans Bay Cable (TBC) is a ±200-kilovolt (kV), 400 MW 85-km long High Voltage Direct Current (DC) buried transmission line linking Pittsburg, CA with San Francisco, CA (SF) beneath the San Francisco Estuary. The TBC runs parallel to the migratory route of various marine species, including green sturgeon, Chinook salmon, and steelhead trout. In July and August 2014, an extensive series of magnetic field measurements were taken using a pair of submerged Geometrics magnetometers towed behind...

  9. Geohydrology, water quality, and estimation of ground-water recharge in San Francisco, California, 1987-92

    Science.gov (United States)

    Phillips, S.P.; Hamlin, S.N.; Yates, E.B.

    1993-01-01

    The city of San Francisco is considering further development of local groundwater resources as a supplemental source of water for potable or nonpotable use. By the year 2010, further water demand is projected to exceed the delivery capacity of the existing supply system, which is fed by surface-water sources; thus supplies are susceptible to drought conditions and damage to conveyance lines by earthquakes. The primary purpose of this study is to describe local geohydrology and water quality and to estimate groundwater recharge in the area of the city of San Francisco. Seven groundwater basins were identified in San Francisco on the basis of geologic and geophysical data. Basins on the east side of the city are relatively thin and contain a greater percentage of fine-grained sediments than those on the west side. The relatively small capacity of the basins and greater potential for contamination from sewer sources may limit the potential for groundwater development on the east side. Basins on the west side of the city have a relatively large capacity and low density sewer network. Water-level data indicate that the southern part of the largest basin on the west side of the city (Westside basin) probably cannot accommodate additional groundwater development without adversely affecting water levels and water quality in Lake Merced; however, the remainder of the basin, which is largely undeveloped, could be developed further. A hydrologic routing model was developed for estimating groundwater recharge throughout San Francisco. The model takes into account climatic factors, land and water use, irrigation, leakage from underground pipes, rainfall runoff, evapotranspiration, and other factors associated with an urban environment. Results indicate that area recharge rates for water years 1987-88 for the 7 groundwater basins ranged from 0.32 to 0.78 feet per year. Recharge for the Westside basin was estimated at 0.51 feet per year. Average annual groundwater recharge

  10. LOWER SAN FRANCISCO WILDERNESS STUDY AREA AND CONTIGUOUS ROADLESS AREAS, ARIZONA AND NEW MEXICO.

    Science.gov (United States)

    Ratte, James C.; Lane, Michael

    1984-01-01

    The Lower San Francisco study area consists of about 40 sq mi, in a strip between 1 and 6 mi wide, along a 20-30 mi stretch of the San Francisco River in Arizona and New Mexico. The study area and contiguous roadless areas were examined for mineral potential and found to have an area of probable mineral-resource potential for base- or precious-metal deposits in middle to upper Tertiary volcanic rocks. The entire area has a largely unassessable potential for base-metal deposits related to igneous intrusives of Laramide age, like those in the nearby Morenci mining district, Arizona. The contiguous roadless area has an area of probable mineral-resource potential for molybdenum or copper deposits related to intrusive igneous rocks in the core of a dacitic volcano of Oligocene age. An area in the west part of the study area has a probable geothermal-resource potential.

  11. System designed for issuing landslide alerts in the San Francisco Bay area

    Science.gov (United States)

    Finley, D.

    1987-01-01

    A system for forecasting landslides during major storms has been developed for the San Francisco Bay area by the U.S Geological Survey and was successfully tested during heavy storms in the bay area during February 1986. Based on the forecasts provided by the USGS, the National Weather Service (NWS) included landslide warnings in its regular weather forecasts or in special weather statements transmitted to local radio and television stations and other news media. USGS scientists said the landslide forecasting and warning system for the San Francisco Bay area can be used as a prototype in developing similar systems for other parts of the Nation susceptible to landsliding. Studies show damage from landslides in the United States averages an estimated $1.5 billion per year. 

  12. Understanding sociocultural and psychological factors affecting transgender people of color in San Francisco.

    Science.gov (United States)

    Bith-Melander, Pollie; Sheoran, Bhupendra; Sheth, Lina; Bermudez, Carlos; Drone, Jennifer; Wood, Woo; Schroeder, Kurt

    2010-01-01

    This ethnographic qualitative study explored the needs of transgender people of color, including biological transitioning issues, gender and group membership identity formation, HIV, and other health issues. The sample consisted of transgender youth and adults of color in San Francisco (N = 43). Data were collected from in-depth interviews with 20 youth and adults and focus groups with 23 individuals. The study focused on perspectives of racial and ethnic minorities from Asian/Pacific Islander, African American, and Latino backgrounds. The medical decision-making perspective was used to gain a deeper understanding of sociocultural and psychological factors affecting transgender individuals of color in San Francisco. The major themes that emerged were gender identity, group membership, transitioning and related issues, sex work, alcohol and drug use, mental health and health care, sense of community, HIV, resources, and other support. Key clinical considerations that health providers can use to improve care of transgender individuals of color are included.

  13. PROYECTO DE RESTAURACIÓN DEL TEMPLO DE SAN FRANCISCO MORELIA, MICHOACÁN

    OpenAIRE

    Fernández Barriga., Blanca Alejandra

    2012-01-01

    El onjunto arquitectónico formado por el templo y exconvento de San Francisco, conocido en el momento de su fundación como Convento Franciscano de San Buenaventura, se ubica en la ciudad de Morelia, Michoacán, justo en el centro de la zona de monumentos históricos. Este conjunto posee un gran valor histórico ya que es una de las primeras edificaciones de la ciudad, mismo que por más de cuatro siglos se ha mantenido como un hito dentro de esta zona, siendo partícipe del devenir his...

  14. How humans and nature have shaped the San Francisco Estuary since the Gold Rush

    Science.gov (United States)

    Jaffe, B.E.

    2009-01-01

    The San Francisco Estuary has undergone dramatic changes since the Gold Rush, as both natural forces and human activities have added and removed massive quantities of sediment, primarily sand and mud. A long-term perspective of sediment movement and patterns of sediment deposition and erosion is vital for effective management of wetlands, sediment contamination, dredging, mining, and other phenomena. Quantitative analysis of historical depth surveys and changes between surveys provides this perspective.

  15. Liminalidad social y negociación cultural: inmigrantes yucatecos en San Francisco, California

    Directory of Open Access Journals (Sweden)

    Inés Cornejo-Portugal

    2012-01-01

    Full Text Available Mediante los conceptos de liminalidad social y negociación cultural analizamos tres estudios de caso de yucatecos migrantes en San Francisco, California. Los migrantes estudiados dan cuenta de las diversas formas como utilizan los recursos sociales a los cuales tienen acceso (familiares, de creencia, de amistad y vecinales y que les permiten encontrar un equilibrio emocional relativo, frente a la tensión cultural de la sociedad destino.

  16. Transcendence and Son Jarocho as Practiced in the San Francisco Bay Area

    OpenAIRE

    Sacolick, Robin

    2016-01-01

    AbstractTranscendence and Son Jarocho as Practiced in the San Francisco Bay AreaRobin SacolickPeople of emerging or non-dominant ethnicities in multicultural, diasporic societies need ways to establish identities, merge strengths, and transcend difficulties. This study explores one way: community practices, by Latina/os and others in the Bay Area, of son jarocho, a centuries-old genre of Mexican music, dance and poetry. While their project revives traditional folklore, it also offers experien...

  17. The Long Road from Babylon to Brentwood: Crisis and Restructuring in the San Francisco Bay Area

    OpenAIRE

    Schafran, Alex B.

    2010-01-01

    AbstractThis dissertation integrates policy analysis, archival research, ethnographic field work, GIS mapping and statistical analysis to build a broad geo-historical understanding of the role of planning, policy, capital and race in the production of the foreclosure crisis in the San Francisco Bay Area. It begins from the premise that an explanation of the foreclosure crisis that focuses solely on either finance capital or the action of homeowners misses the critical importance of history, g...

  18. Particulate Matter Concentrations in San Francisco Bay Area Rapid Transit (BART) Train Stations

    Science.gov (United States)

    Newsome, L.; Macias, S.; Romero, N.; Lockett, N.; Polar, J.; Madrigal, C.; Lopez, F.; Sanchez, R.; Webster, D.; Torio, M.; Rios, V.; Marks-Block, T.; Toli, F.

    2012-12-01

    As part of a general effort to assess air quality in different regions of the San Francisco Bay Area, we collected Particulate Matter (PM) data within passenger train cars along multiple commuter train lines simultaneously during the summer and fall of 2012. We visited numerous Bay Area Rapid Transit (BART) system stations, including those along the Fremont, Pittsburg and SF/Daly City lines. In conducting this study we used a Dustrak 8530 aerosol sensor equipped with a Global Positioning System (GPS) receiver to measure PM size 2.5 μm concentrations every second. Of all the BART stations we visited, average PM concentration levels at the Embarcadero station in San Francisco were the highest during multiple visits, with a value of 104.95 μg/m3. We also noted that high levels of PM 2.5 were released when the cloth seats on the trains were struck, which resulted in significant, temporary increases of hazardous PM levels of up to 3000 μg/m3! Embarcadero station's high PM concentration correlates to past research in other underground train stations throughout the world, where PM produced through the abrasive interaction of train wheels and tracks or brake pads becomes trapped. Compared to levels measured at outdoor stations (average of 8.52μg/m3) and other underground stations, levels detected at the Embarcadero station are particularly alarming. We believe this is due to the fact that this station is located at one end of a long, underground and underwater transbay tunnel that connects the East San Francisco Bay area to San Francisco to the west. To reduce PM exposure risk to BART employees and passengers, we suggest increasing and/or installing filtration and ventilation systems, which should substantially reduce PM concentrations at Embarcadero station.

  19. Heat wave brings an unprecedented red tide to San Francisco Bay

    Science.gov (United States)

    Cloern, James E.; Schraga, Tara S.; Lopez, Cary B.

    2005-01-01

    An exceptional red tide in San Francisco Bay was observed on 8 September 2004. The red tide had chlorophyll concentrations approaching 200 mg/m3 (Figure 1) in red/purple surface streaks containing high abundances of the dinoflagellate Akashiwo sanguinea. Red tides and harmful algal blooms (HABs) are common features of coastal ecosystems, and their growing frequency is a suspected outcome of coastal eutrophication.

  20. Global Health Diplomacy, "San Francisco Values," and HIV/AIDS: From the Local to the Global.

    Science.gov (United States)

    Kevany, Sebastian

    2015-01-01

    San Francisco has a distinguished history as a cosmopolitan, progressive, and international city, including extensive associations with global health. These circumstances have contributed to new, interdisciplinary scholarship in the field of global health diplomacy (GHD). In the present review, we describe the evolution and history of GHD at the practical and theoretical levels within the San Francisco medical community, trace related associations between the local and the global, and propose a range of potential opportunities for further development of this dynamic field. We provide a historical overview of the development of the "San Francisco Model" of collaborative, community-owned HIV/AIDS treatment and care programs as pioneered under the "Ward 86" paradigm of the 1980s. We traced the expansion and evolution of this model to the national level under the Ryan White Care Act, and internationally via the President's Emergency Plan for AIDS Relief. In parallel, we describe the evolution of global health diplomacy practices, from the local to the global, including the integration of GHD principles into intervention design to ensure social, political, and cultural acceptability and sensitivity. Global health programs, as informed by lessons learned from the San Francisco Model, are increasingly aligned with diplomatic principles and practices. This awareness has aided implementation, allowed policymakers to pursue related and progressive social and humanitarian issues in conjunction with medical responses, and elevated global health to the realm of "high politics." In the 21st century, the integration between diplomatic, medical, and global health practices will continue under "smart global health" and GHD paradigms. These approaches will enhance intervention cost-effectiveness by addressing and optimizing, in tandem with each other, a wide range of (health and non-health) foreign policy, diplomatic, security, and economic priorities in a synergistic manner

  1. Remedial Investigation Report, Presidio Main Installation, Presidio of San Francisco. Volume 1: Text

    Science.gov (United States)

    1997-01-01

    which drains to the San Francisco Bay. Stormwater runoff from developed portions of the installation is collected by a system of swales and storm drains and...and to assess the distribution of potential contaminants in the drainage pathways. Sediment samples were collected from inside storm drains or catch...Sediment that was collected from open ditches (versus storm drains ) and from the Baker Beach seep, Lobos Creek, and Mountain Lake was evaluated based

  2. Groundwater quality in the North San Francisco Bay shallow aquifer, California

    Science.gov (United States)

    Bennett, George L.; Fram, Miranda S.

    2018-02-23

    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 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 North San Francisco Bay Shallow Aquifer constitutes one of the study units being evaluated.

  3. Teresa Gowan, Hobos, Hustlers and Backsliders: Homeless in San Francisco

    Directory of Open Access Journals (Sweden)

    João Aldeia

    2012-11-01

    Full Text Available Teresa Gowan apresenta‑nos uma obra atípica no contexto da produção de conhecimento científico sobre o fenómeno dos sem‑abrigo nos Estados Unidos da América (EUA. Recorrendo a um trabalho etnográfico notável, desenvolvido ao longo da segunda metade da década de 1990 em São Francisco, a autora enquadra o seu estudo no contexto sócio-histórico e geográfico mais vasto, articulando a análise do terreno com as teorias acerca do fenómeno e com os registos das perspectivas das próprias pessoas que ...

  4. Mercury-Contaminated Hydraulic Mining Debris in San Francisco Bay

    OpenAIRE

    Bouse, Robin M; Fuller, Christopher C.; Luoma, Sam; Hornberger, Michelle I; Jaffe, Bruce E; Smith, Richard E.

    2010-01-01

    The hydraulic gold-mining process used during the California Gold Rush and in many developing countries today contributes enormous amounts of sediment to rivers and streams. Commonly, accompanying this sediment are contaminants such as elemental mercury and cyanide used in the gold extraction process. We show that some of the mercury-contaminated sediment created by hydraulic gold mining in the Sierra Nevada, between 1852 and 1884, ended up over 250 kilometers (km) away in San Franci...

  5. Map showing thickness of young bay mud, southern San Francisco Bay, California

    Science.gov (United States)

    McDonald, Sandra D.; Nichols, Donald R.; Wright, Nancy A.; Atwater, Brian

    1978-01-01

    Soft water-saturated estuarine deposits less than 10,000 years old underlie the southern part of San Francisco bay and the present and former marshlands that border the bay. Known locally as bay mud or as young bay mud, these deposits, and the estuarine environment that produces them, are of major importance in making decision on land use and development in the San Francisco Bay area. Knowledge of the distribution, thickness, and physical properties of young bay mud is critical to the feasibility, design, and maintenance of structures built on it. Fore this reason, numerous attempts have been made in the past to map or describe these characteristics (Mitchell, 1963; Goldman, 1969; McDonald and Nichols, 1974). The accompanying map of bay-mud thickness significantly revises part of an earlier compilation by Kahle and Goldman (1969) and includes new data from approximately 2400 boreholes, most of which have been drilled during the past 15 years. It also incorporates information on historic margins of San Francisco Bay and its tidal marshes (Nichols and Wright, 1971). Although this map was compelled mostly from data gathered during foundation investigations and construction projects, it is mostly from data gathered during foundation investigations and construction projects, it is not a substitute for such studies. Rather, the map provides regional information for land-use planning, seismic zonation, and design of foundation investigations.

  6. A social and historical perspective of the San Francisco Gay Men's Chorus.

    Science.gov (United States)

    Hilliard, Russell E

    2008-01-01

    This study sought to understand the various roles music played for gay men who were members of the San Francisco Gay Men's Chorus, the world's first gay men's chorus. Specifically, it answers the following questions: What is the demographic profile of the chorus members? How has the chorus shaped or reflected social issues; how has the chorus shaped or reflected political issues; how has the music evolved over time?; How was the chorus impacted by the HIV/AIDS epidemic? Historical information for this study was gathered through eight interviews of original and long-time choral members as well as the current artistic director. Interviews were conducted in San Francisco at the San Francisco Gay Men's Chorus office, and additional data were derived from programs of previous choral concerts, two questionnaires (Internalized Homophobia Scale and Gay Chorus Questionnaire), and observations of choral rehearsals and concerts. As a follow-up to a previous study documenting the formation of the chorus in 1978-1982, this study historically documents the chorus's evolution from 1983 through 2003, emphasizing the chorus's impact on social and political issues, the musicality of the chorus, and the impact of HIV/AIDS on the chorus.

  7. Opioid Overdose Deaths in the City and County of San Francisco: Prevalence, Distribution, and Disparities.

    Science.gov (United States)

    Visconti, Adam J; Santos, Glenn-Milo; Lemos, Nikolas P; Burke, Catherine; Coffin, Phillip O

    2015-08-01

    Drug overdose is now the leading cause of unintentional death nationwide, driven by increased prescription opioid overdoses. To better understand urban opioid overdose deaths, this paper examines geographic, demographic, and clinical differences between heroin-related decedents and prescription opioid decedents in San Francisco from 2010 to 2012. During this time period, 331 individuals died from accidental overdose caused by opioids (310 involving prescription opioids and 31 involving heroin). Deaths most commonly involved methadone (45.9%), morphine (26.9%), and oxycodone (21.8%). Most deaths also involved other substances (74.9%), most commonly cocaine (35.3%), benzodiazepines (27.5%), antidepressants (22.7%), and alcohol (19.6%). Deaths were concentrated in a small, high-poverty, central area of San Francisco and disproportionately affected African-American individuals. Decedents in high-poverty areas were significantly more likely to die from methadone and cocaine, whereas individuals from more affluent areas were more likely die from oxycodone and benzodiazepines. Heroin decedents were more likely to be within a younger age demographic, die in public spaces, and have illicit substances rather than other prescription opioids. Overall, heroin overdose death, previously common in San Francisco, is now rare. Prescription opioid overdose has emerged as a significant concern, particularly among individuals in high-poverty areas. Deaths in poor and affluent regions involve different causative opioids and co-occurring substances.

  8. Effect of distal Sacramento-San Joaquin Delta outflow on suspended-sediment flux in Lower South San Francisco Bay

    Science.gov (United States)

    Livsey, D. N.; Downing-Kunz, M.; Schoellhamer, D. H.; Shellenbarger, G.; Wright, S. A.

    2016-12-01

    Tidal marshes are an important component of estuarine ecosystems. Within the San Francisco Bay Estuary (SFB) tidal marshes play an important role in food web dynamics, are home to an array of endemic mammals, birds, and fishes, filter pollutants, and dampen coastal flooding. With 80% of SFB tidal marshes lost to human development, numerous restoration efforts are underway. The largest tidal marsh restoration project in SFB, the South Bay Salt Pond Restoration Project, is underway in Lower South San Francisco Bay to restore 60,000 ha of this critical habitat; however, rising sea levels, could jeopardize these gains without concomitant vertical accretion rates of the marsh surface via organic matter accumulation and sediment deposition. Recent work in Lower South Bay using continuously collected data from water years (WY) 2009-11 indicates that the direction of net springtime residual sediment flux is related to the amount of springtime Sacramento-San Joaquin Delta (Delta) outflow. Large outflow freshens the Central Bay, causing a density gradient and inverse gravitational circulation that flushes Lower South Bay. In this study we extend the sediment budget for Lower South Bay from WY 2011 to present using 15-minute turbidity and velocity data paired with Acoustic Doppler Current Profiler cross-sectional measurements and in situ suspended-sediment concentration samples to: 1) further examine the mechanisms controlling net springtime residual sediment flux, and 2) further test the hypothesis that Delta outflow controls the direction of net sediment flux for Lower South Bay.

  9. Towards the Development of the National Ocean Service San Francisco Bay Operational Forecast System

    Directory of Open Access Journals (Sweden)

    Machuan Peng

    2014-03-01

    Full Text Available The National Ocean Service (NOS, Center for Operational Products and Services installed a Physical Oceanographic Real Time System (PORTS in San Francisco Bay during 1998 to provide water surface elevation, currents at PORTS prediction depth as well as near-surface temperature and salinity. To complement the PORTS, a new nowcast/forecast system (consistent with NOS procedures has been constructed. This new nowcast/forecast system is based on the Finite Volume Coastal Ocean Model (FVCOM using a computational domain, which extends from Rio Vista on the Sacramento River and Antioch on the San Joaquin River through Suisun and San Pablo Bays and Upper and Lower San Francisco Bay out onto the continental shelf. This paper presents the FVCOM setup, testing, and validation for tidal and hindcast scenarios. In addition, the San Francisco Bay Operational Forecast System (SFBOFS setup within the NOS Coastal Ocean Model Framework (COMF is discussed. The SFBOFS performance during a semi-operational nowcast/forecast test period is presented and the production webpage is also briefly introduced. FVCOM, the core of SFBOFS, has been found to run robustly during the test period. Amplitudes and epochs of the M2 S2, N2, K2, K1, O1, P1, and Q1 constituents from the model tide-only simulation scenario are very close to the observed values at all stations. NOS skill assessment and RMS errors of all variables indicate that most statistical parameters pass the assessment criteria, and the model predictions are in agreement with measurements for both hindcast and semi-operational nowcast/forecast scenarios.

  10. A history of intertidal flat area in south San Francisco Bay, California: 1858 to 2005

    Science.gov (United States)

    Jaffe, Bruce; Foxgrover, Amy

    2006-01-01

    A key question in salt pond restoration in South San Francisco Bay is whether sediment sinks created by opening ponds will result in the loss of intertidal flats. Analyses of a series of bathymetric surveys of South San Francisco Bay made from 1858 to 2005 reveal changes in intertidal flat area in both space and time that can be used to better understand the pre-restoration system. This analysis also documents baseline conditions of intertidal flats that may be altered by restoration efforts. From 1858 to 2005, intertidal flat area decreased by about 25% from 69.2 +6.4/-7.6 km2 to 51.2 +4.8/-5.8 km2. Intertidal flats in the north tended to decrease in area during the period of this study whereas those south of Dumbarton Bridge were either stable or increased in area. From 1983 to 2005, intertidal flats south of Dumbarton Bridge increased from 17.6 +1.7/-2.5 km2 to 24.2 +1.0/-1.8 km2. Intertidal flats along the east shore of the bay tended to be more erosional and decreased in area while those along the west shore of the bay did not significantly change in area. Loss of intertidal flats occurred intermittently along the eastern shore of the bay north of the Dumbarton Bridge. There was little or no loss from 1931 to 1956 and from 1983 to 2005. Predictions of future change in intertidal flat area that do not account for this spatial and temporal variability are not likely to be accurate. The causes of the spatial and temporal variability in intertidal flat area in South San Francisco Bay are not fully understood, but appear related to energy available to erode sediments, sediment redistribution from north to south in the bay, and sediment available to deposit on the flats. Improved understanding of sediment input to South San Francisco Bay, especially from Central Bay, how it is likely to change in the future, the redistribution of sediment within the bay, and ultimately its effect on intertidal flat area would aid in the management of restoration of South San

  11. Anthropogenic influence on recent bathymetric change in west-central San Francisco Bay

    Science.gov (United States)

    Barnard, Patrick L.; Kvitek, Rikk G.

    2010-01-01

    Two multibeam sonar surveys of west-central San Francisco Bay, California, were conducted in 1997 and 2008. Bathymetric change analysis between the two surveys indicates a loss of 14.1 million cubic meters (-3.1 cm/yr-1) of sediment during this time period, representing an approximately three-fold acceleration of the rate that was observed from prior depth change analysis from 1947 to 1979 for all of Central Bay, using more spatially coarse National Ocean Service (NOS) soundings. The portions of the overlapping survey areas between 1997 and 2008 designated as aggregate mining lease sites lost sediment at five times the rate of the remainder of west-central San Francisco Bay. Despite covering only 28% of the analysis area, volume change within leasing areas accounted for 9.2 million cubic meters of sediment loss, while the rest of the area lost 4.9 million cubic meters of sediment. The uncertainty of this recent analysis is more tightly constrained due to more stringent controls on vertical and horizontal position via tightly coupled, inertially aided differential Global Positioning Systems (GPS) solutions for survey vessel trajectory that virtually eliminate inaccuracies from traditional tide modeling and vessel motion artifacts. Further, quantification of systematic depth measurement error can now be calculated through comparison of static surfaces (e.g., bedrock) between surveys using seafloor habitat maps based on acoustic backscatter measurements and ground-truthing with grab samples and underwater video. Sediment loss in the entire San Francisco Bay Coastal System during the last half-century,as estimated from a series of bathymetric change studies, is 240 million cubic meters, and most of this is believed to be coarse sediment (i.e., sand and gravel) from Central Bay and the San Francisco Bar, which is likely to limit the sand supply to adjacent, open-coast beaches. This hypothesis is supported by a calibrated numerical model in a related study that indicates

  12. Coastal monitoring of the May 2005 dredge disposal offshore of Ocean Beach, San Francisco, Calif.

    Science.gov (United States)

    Barnard, Patrick L.; Hanes, Daniel M.

    2006-01-01

    Ocean Beach, California, contains an erosion hot spot in the shadow of the San Francisco ebb tidal delta south of Sloat Boulevard that threatens valuable public infrastructure as well as the safe recreational use of the beach. In an effort to reduce the erosion at this location and avoid hazardous navigation conditions at the current disposal site (SF-8), a new plan for the management of sediment dredged annually from the main shipping channel at the mouth of Francisco Bay was implemented in May 2005 by the United States Army Corps of Engineers, San Francisco District (COE). The objective for COE was to perform a test dredge disposal of ~230,000 m3 (300,000 yd3) of sand just offshore of the erosion hot spot, in depths between approximately 9 and 14 m. This disposal site was chosen because it is in a location where the strong tidal currents associated with the mouth of San Francisco Bay and waves can potentially feed sediment toward the littoral zone in the reach of the beach that is experiencing critical erosion. The onshore migration of sediment from the target disposal location might feed the primary longshore bar or the nearshore zone, and provide a buffer to erosion that peaks during winter months when large waves impact the region. The U.S. Geological Survey (USGS), in collaboration with the Sea Floor Mapping Lab (SFML) of California State University, Monterey Bay, monitored the initial bathymetric evolution of the test dredge disposal site and the adjacent coastal region from May 2005 to November 2005. This paper reports on this monitoring effort and assesses the short-term coastal response.

  13. Carbon Sequestration in Mediterranean Tidal Wetlands: San Francisco Bay and the Ebro River Delta (Invited)

    Science.gov (United States)

    Callaway, J.; Fennessy, S.; Ibanez, C.

    2013-12-01

    Tidal wetlands accumulate soil carbon at relatively rapid rates, in large part because they build soil to counteract increases in sea-level rise. Because of the rapid rates of carbon sequestration, there is growing interest in evaluating carbon dynamics in tidal wetlands around the world; however, few measurements have been completed for mediterranean-type tidal wetlands, which tend to have relatively high levels of soil salinity, likely affecting both plant productivity and decomposition rates. We measured sediment accretion and carbon sequestration rates at tidal wetlands in two mediterranean regions: the San Francisco Bay Estuary (California, USA) and the Ebro River Delta (Catalonia, Spain). Sampling sites within each region represented a range of conditions in terms of soil salinity and plant communities, and these sites serve as potential analogs for long-term carbon sequestration in restored wetlands, which could receive credits under emerging policies for carbon management. Within San Francisco Bay, we collected six sediment cores per site at four salt marshes and two brackish tidal wetlands (two transects with three stations per transect at each site) in order to identify spatial variation both within and among wetlands in the Estuary. At the Ebro Delta, individual sediment cores were collected across 14 tidal wetland sites, including salt and brackish marshes from impounded areas, river mouths, coastal lagoon, and open bay settings. Cores were collected to 50 cm, and cores were dated using 137Cs and 210Pb. Most sites within San Francisco accreted 0.3-0.5 cm/yr, with slightly higher rates of accretion at low marsh stations; accretions rates based on 137Cs were slightly higher than those based on 210Pb, likely because of the shorter time frame covered by 137Cs dating. Accretion rates from the Ebro Delta sites were similar although more variable, with rates based on 137Cs ranging from 0.1 to 0.9 cm/yr and reflecting the wide range of conditions and management

  14. Mercury concentrations and loads in a large river system tributary to San Francisco Bay, California, USA

    Science.gov (United States)

    David, N.; McKee, L.J.; Black, F.J.; Flegal, A.R.; Conaway, C.H.; Schoellhamer, D.H.; Ganju, N.K.

    2009-01-01

    In order to estimate total mercury (HgT) loads entering San Francisco Bay, USA, via the Sacramento-San Joaquin River system, unfiltered water samples were collected between January 2002 and January 2006 during high flow events and analyzed for HgT. Unfiltered HgT concentrations ranged from 3.2 to 75 ng/L and showed a strong correlation (r2 = 0.8, p < 0.001, n = 78) to suspended sediment concentrations (SSC). During infrequent large floods, HgT concentrations relative to SSC were approximately twice as high as observed during smaller floods. This difference indicates the transport of more Hg-contaminated particles during high discharge events. Daily HgT loads in the Sacramento-San Joaquin River at Mallard Island ranged from below the limit of detection to 35 kg. Annual HgT loads varied from 61 ?? 22 kg (n = 5) in water year (WY) 2002 to 470 ?? 170 kg (n = 25) in WY 2006. The data collected will assist in understanding the long-term recovery of San Francisco Bay from Hg contamination and in implementing the Hg total maximum daily load, the long-term cleanup plan for Hg in the Bay. ?? 2009 SETAC.

  15. 78 FR 2952 - Foreign-Trade Zone 3-San Francisco, California; Application for Expansion and Expansion of...

    Science.gov (United States)

    2013-01-15

    ... Foreign-Trade Zones Board Foreign-Trade Zone 3--San Francisco, California; Application for Expansion and Expansion of Service Area Under Alternative Site Framework An application has been submitted to the Foreign..., 10/20/2010). The zone project currently has a service area that includes the City and County of San...

  16. A Tidally Averaged Sediment-Transport Model for San Francisco Bay, California

    Science.gov (United States)

    Lionberger, Megan A.; Schoellhamer, David H.

    2009-01-01

    A tidally averaged sediment-transport model of San Francisco Bay was incorporated into a tidally averaged salinity box model previously developed and calibrated using salinity, a conservative tracer (Uncles and Peterson, 1995; Knowles, 1996). The Bay is represented in the model by 50 segments composed of two layers: one representing the channel (>5-meter depth) and the other the shallows (0- to 5-meter depth). Calculations are made using a daily time step and simulations can be made on the decadal time scale. The sediment-transport model includes an erosion-deposition algorithm, a bed-sediment algorithm, and sediment boundary conditions. Erosion and deposition of bed sediments are calculated explicitly, and suspended sediment is transported by implicitly solving the advection-dispersion equation. The bed-sediment model simulates the increase in bed strength with depth, owing to consolidation of fine sediments that make up San Francisco Bay mud. The model is calibrated to either net sedimentation calculated from bathymetric-change data or measured suspended-sediment concentration. Specified boundary conditions are the tributary fluxes of suspended sediment and suspended-sediment concentration in the Pacific Ocean. Results of model calibration and validation show that the model simulates the trends in suspended-sediment concentration associated with tidal fluctuations, residual velocity, and wind stress well, although the spring neap tidal suspended-sediment concentration variability was consistently underestimated. Model validation also showed poor simulation of seasonal sediment pulses from the Sacramento-San Joaquin River Delta at Point San Pablo because the pulses enter the Bay over only a few days and the fate of the pulses is determined by intra-tidal deposition and resuspension that are not included in this tidally averaged model. The model was calibrated to net-basin sedimentation to calculate budgets of sediment and sediment-associated contaminants. While

  17. Heavy mineral analysis for assessing the provenance of sandy sediment in the San Francisco Bay Coastal System

    Science.gov (United States)

    Wong, Florence L.; Woodrow, Donald L.; McGann, Mary

    2013-01-01

    Heavy or high-specific gravity minerals make up a small but diagnostic component of sediment that is well suited for determining the provenance and distribution of sediment transported through estuarine and coastal systems worldwide. By this means, we see that surficial sand-sized sediment in the San Francisco Bay Coastal System comes primarily from the Sierra Nevada and associated terranes by way of the Sacramento and San Joaquin Rivers and is transported with little dilution through the San Francisco Bay and out the Golden Gate. Heavy minerals document a slight change from the strictly Sierran-Sacramento mineralogy at the confluence of the two rivers to a composition that includes minor amounts of chert and other Franciscan Complex components west of Carquinez Strait. Between Carquinez Strait and the San Francisco Bar, Sierran sediment is intermingled with Franciscan-modified Sierran sediment. The latter continues out the Gate and turns southward towards beaches of the San Francisco Peninsula. The Sierran sediment also fans out from the San Francisco Bar to merge with a Sierran province on the shelf in the Gulf of the Farallones. Beach-sand sized sediment from the Russian River is transported southward to Point Reyes where it spreads out to define a Franciscan sediment province on the shelf, but does not continue southward to contribute to the sediment in the Golden Gate area.

  18. Forecasting Selenium Discharges to the San Francisco Bay-Delta Estuary: Ecological Effects of A Proposed San Luis Drain Extension

    Science.gov (United States)

    Presser, Theresa S.; Luoma, Samuel N.

    2006-01-01

    Selenium discharges to the San Francisco Bay-Delta Estuary (Bay-Delta) could change significantly if federal and state agencies (1) approve an extension of the San Luis Drain to convey agricultural drainage from the western San Joaquin Valley to the North Bay (Suisun Bay, Carquinez Strait, and San Pablo Bay); (2) allow changes in flow patterns of the lower San Joaquin River and Bay-Delta while using an existing portion of the San Luis Drain to convey agricultural drainage to a tributary of the San Joaquin River; or (3) revise selenium criteria for the protection of aquatic life or issue criteria for the protection of wildlife. Understanding the biotransfer of selenium is essential to evaluating effects of selenium on Bay-Delta ecosystems. Confusion about selenium threats to fish and wildlife stem from (1) monitoring programs that do not address specific protocols necessary for an element that bioaccumulates; and (2) failure to consider the full complexity of the processes that result in selenium toxicity. Past studies show that predators are more at risk from selenium contamination than their prey, making it difficult to use traditional methods to predict risk from environmental concentrations alone. This report presents an approach to conceptualize and model the fate and effects of selenium under various load scenarios from the San Joaquin Valley. For each potential load, progressive forecasts show resulting (1) water-column concentration; (2) speciation; (3) transformation to particulate form; (4) particulate concentration; (5) bioaccumulation by invertebrates; (6) trophic transfer to predators; and (7) effects on those predators. Enough is known to establish a first-order understanding of relevant conditions, biological response, and ecological risks should selenium be discharged directly into the North Bay through a conveyance such as a proposed extension of the San Luis Drain. The approach presented here, the Bay-Delta selenium model, determines the mass, fate

  19. Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Science.gov (United States)

    Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2017-06-27

    Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

  20. Stable lead isotopic analyses of historic and contemporary lead contamination of San Francisco Bay estuary

    Science.gov (United States)

    Ritson, P.I.; Bouse, R.M.; Flegal, A.R.; Luoma, S.N.

    1999-01-01

    Variations in stable lead isotopic composition (240Pb, 206Pb, 207Pb, 208Pb) in three sediment cores from the San Francisco Bay estuary document temporal changes in sources of lead during the past two centuries. Sediment, with lead from natural geologic sources, and relatively homogeneous lead isotopic compositions are overlain by sediments whose isotopic compositions indicate change in the sources of lead associated with anthropogenic modification of the estuary. The first perturbations of lead isotopic composition in the cores occur in the late 1800s concordant with the beginning of industrialization around the estuary. Large isotopic shifts, toward lower 206Pb/207Pb, occur after the turn of the century in both Richardson and San Pablo Bays. A similar relationship among lead isotopic compositions and lead concentrations in both Bays suggest contamination from the same source (a lead smelter). The uppermost sediments (post 1980) of all cores also have a relatively homogenous lead isotopic composition distinct from pre-anthropogenic and recent aerosol signatures. Lead isotopic compositions of leachates from fourteen surface sediments and five marsh samples from the estuary were also analyzed. These analyses suggest that the lead isotopic signature identified in the upper horizons of the cores is spatially homogeneous among recently deposited sediments throughout the estuary. Current aerosol lead isotopic compositions [Smith, D.R., Niemeyer, S., Flegal, A.R., 1992. Lead sources to California sea otters: industrial inputs circumvent natural lead biodepletion mechanisms. Environmental Research 57, 163-175] are distinct from the isotopic compositions of the surface sediments, suggesting that the major source of lead is cycling of historically contaminated sediments back through the water column. Both the upper core sediments and surface sediments apparently derive their lead predominantly from sources internal to the estuary. These results support the idea that

  1. Quaternary geology of Alameda County, and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin counties, California: a digital database

    Science.gov (United States)

    Helley, E.J.; Graymer, R.W.

    1997-01-01

    Alameda County is located at the northern end of the Diablo Range of Central California. It is bounded on the north by the south flank of Mount Diablo, one of the highest peaks in the Bay Area, reaching an elevation of 1173 meters (3,849 ft). San Francisco Bay forms the western boundary, the San Joaquin Valley borders it on the east and an arbitrary line from the Bay into the Diablo Range forms the southern boundary. Alameda is one of the nine Bay Area counties tributary to San Francisco Bay. Most of the country is mountainous with steep rugged topography. Alameda County is covered by twenty-eight 7.5' topographic Quadrangles which are shown on the index map. The Quaternary deposits in Alameda County comprise three distinct depositional environments. One, forming a transgressive sequence of alluvial fan and fan-delta facies, is mapped in the western one-third of the county. The second, forming only alluvial fan facies, is mapped in the Livermore Valley and San Joaquin Valley in the eastern part of the county. The third, forming a combination of Eolian dune and estuarine facies, is restricted to the Alameda Island area in the northwestern corner of the county.

  2. Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California

    Science.gov (United States)

    McLaughlin, R.J.; Langenheim, V.E.; Schmidt, K.M.; Jachens, R.C.; Stanley, R.G.; Jayko, A.S.; McDougall, K.A.; Tinsley, J.C.; Valin, Z.C.

    1999-01-01

    In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly understood. Based on recent geologic mapping and geophysical investigations, we propose that the range-front thrust system evolved in conjunction with development of the San Andreas fault system. In the early Miocene, the region was dominated by a system of northwestwardly propagating, basin-bounding, transtensional faults. Beginning as early as middle Miocene time, however, the transtensional faulting was superseded by transpressional NE-stepping thrust and reverse faults of the range-front thrust system. Age constraints on the thrust faults indicate that the locus of contraction has focused on the Monte Vista, Shannon, and Berrocal faults since about 4.8 Ma. Fault slip and fold reconstructions suggest that crustal shortening between the San Andreas fault and the Santa Clara Valley within this time frame is ~21%, amounting to as much as 3.2 km at a rate of 0.6 mm/yr. Rates probably have not remained constant; average rates appear to have been much lower in the past few 100 ka. The distribution of coseismic surface contraction during the Loma Prieta earthquake, active seismicity, late Pleistocene to Holocene fluvial terrace warping, and geodetic data further suggest that the active range-front thrust system includes blind thrusts. Critical unresolved issues include information on the near-surface locations of buried thrusts, the timing of recent thrust earthquake events, and their recurrence in relation to earthquakes on the San Andreas fault.

  3. Sediment transport in the San Francisco Bay Coastal System: An overview

    Science.gov (United States)

    Barnard, Patrick L.; Schoellhamer, David H.; Jaffe, Bruce E.; Lester J. McKee,

    2013-01-01

    The papers in this special issue feature state-of-the-art approaches to understanding the physical processes related to sediment transport and geomorphology of complex coastal-estuarine systems. Here we focus on the San Francisco Bay Coastal System, extending from the lower San Joaquin-Sacramento Delta, through the Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized estuary that is impacted by numerous anthropogenic activities common to many large estuaries, including a mining legacy, channel dredging, aggregate mining, reservoirs, freshwater diversion, watershed modifications, urban run-off, ship traffic, exotic species introductions, land reclamation, and wetland restoration. The Golden Gate strait is the sole inlet connecting the Bay to the Pacific Ocean, and serves as the conduit for a tidal flow of ~ 8 x 109 m3/day, in addition to the transport of mud, sand, biogenic material, nutrients, and pollutants. Despite this physical, biological and chemical connection, resource management and prior research have often treated the Delta, Bay and adjacent ocean as separate entities, compartmentalized by artificial geographic or political boundaries. The body of work herein presents a comprehensive analysis of system-wide behavior, extending a rich heritage of sediment transport research that dates back to the groundbreaking hydraulic mining-impact research of G.K. Gilbert in the early 20th century.

  4. Sediment transport in the San Francisco Bay Coastal System: an overview

    Science.gov (United States)

    Barnard, Patrick L.; Schoellhamer, David H.; Jaffe, Bruce E.; McKee, Lester J.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    The papers in this special issue feature state-of-the-art approaches to understanding the physical processes related to sediment transport and geomorphology of complex coastal–estuarine systems. Here we focus on the San Francisco Bay Coastal System, extending from the lower San Joaquin–Sacramento Delta, through the Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized estuary that is impacted by numerous anthropogenic activities common to many large estuaries, including a mining legacy, channel dredging, aggregate mining, reservoirs, freshwater diversion, watershed modifications, urban run-off, ship traffic, exotic species introductions, land reclamation, and wetland restoration. The Golden Gate strait is the sole inlet connecting the Bay to the Pacific Ocean, and serves as the conduit for a tidal flow of ~ 8 × 109 m3/day, in addition to the transport of mud, sand, biogenic material, nutrients, and pollutants. Despite this physical, biological and chemical connection, resource management and prior research have often treated the Delta, Bay and adjacent ocean as separate entities, compartmentalized by artificial geographic or political boundaries. The body of work herein presents a comprehensive analysis of system-wide behavior, extending a rich heritage of sediment transport research that dates back to the groundbreaking hydraulic mining-impact research of G.K. Gilbert in the early 20th century.

  5. A molecular epidemiologic analysis of tuberculosis trends in San Francisco, 1991-1997.

    Science.gov (United States)

    Jasmer, R M; Hahn, J A; Small, P M; Daley, C L; Behr, M A; Moss, A R; Creasman, J M; Schecter, G F; Paz, E A; Hopewell, P C

    1999-06-15

    To decrease tuberculosis case rates and cases due to recent infection (clustered cases) in San Francisco, California, tuberculosis control measures were intensified beginning in 1991 by focusing on prevention of Mycobacterium tuberculosis transmission and on the use of preventive therapy. To describe trends in rates of tuberculosis cases and clustered cases in San Francisco from 1991 through 1997. Population-based study. San Francisco, California. Persons with tuberculosis diagnosed between 1 January 1991 and 31 December 1997. DNA fingerprinting was performed. During sequential 1-year intervals, changes in annual case rates per 100,000 persons for all cases, clustered cases (cases with M. tuberculosis isolates having identical fingerprint patterns), and cases in specific subgroups with high rates of clustering (persons born in the United States and HIV-infected persons) were examined. Annual tuberculosis case rates peaked at 51.2 cases per 100,000 persons in 1992 and decreased significantly thereafter to 29.8 cases per 100,000 persons in 1997 (P < 0.001). The rate of clustered cases decreased significantly over time in the entire study sample (from 10.4 cases per 100,000 persons in 1991 to 3.8 cases per 100,000 persons in 1997 [P < 0.001]), in persons born in the United States (P < 0.001), and in HIV-infected persons (P = 0.003). The rates of tuberculosis cases and clustered tuberculosis cases decreased both overall and among persons in high-risk groups. This occurred in a period during which tuberculosis control measures were intensified.

  6. Knowledge, Indications and Willingness to Take Pre-Exposure Prophylaxis among Transwomen in San Francisco, 2013.

    Directory of Open Access Journals (Sweden)

    Erin C Wilson

    Full Text Available Safe and effective HIV prevention strategies are needed for transwomen. Transwomen in the US have a 34 times greater odds of being infected with HIV than all adults age 15-49, and in San Francisco, California 42.4% of transwomen are estimated to be infected with HIV. Pre-exposure prophylaxis (PrEP is the first biomedical intervention with promise for reducing HIV acquisition in transwomen. However, little is known about whether transwomen know about PrEP, are taking PrEP and would be good candidates for PrEP based on their risk profile and behaviors. A population-based dataset was analyzed to determine how many transwomen in San Francisco knew about PrEP by the end of 2013 - more than a year after iPrex results demonstrated efficacy of PrEP in preventing HIV. We found that of 233 transwomen, only 13.7% had heard of PrEP. Transwomen who were living with HIV compared to those who were HIV-negative, and those who recently injected drugs compared to non-injection drug users were more likely to have heard of PrEP. Based on CDC guidelines for PrEP among MSM and IDU, 45 (30.2% transwomen of the 149 HIV-negative transwomen in the sample were candidates for PrEP. This estimate based on CDC criteria is arguably low. Given that almost half of transwomen in San Francisco are living with HIV, this findings points to a need for further consideration of PrEP criteria that are specific and tailored to the risks for HIV faced by transwomen that are different from MSM and injection drug users. Research to scale up access and test the effectiveness of PrEP for transwomen is also urgently needed.

  7. Integrating Fluvial and Oceanic Drivers in Operational Flooding Forecasts for San Francisco Bay

    Science.gov (United States)

    Herdman, Liv; Erikson, Li; Barnard, Patrick; Kim, Jungho; Cifelli, Rob; Johnson, Lynn

    2016-04-01

    The nine counties that make up the San Francisco Bay area are home to 7.5 million people and these communties are susceptible to flooding along the bay shoreline and inland creeks that drain to the bay. A forecast model that integrates fluvial and oceanic drivers is necessary for predicting flooding in this complex urban environment. The U.S. Geological Survey ( USGS) and National Weather Service (NWS) are developing a state-of-the-art flooding forecast model for the San Francisco Bay area that will predict watershed and ocean-based flooding up to 72 hours in advance of an approaching storm. The model framework for flood forecasts is based on the USGS-developed Coastal Storm Modeling System (CoSMoS) that was applied to San Francisco Bay under the Our Coast Our Future project. For this application, we utilize Delft3D-FM, a hydrodynamic model based on a flexible mesh grid, to calculate water levels that account for tidal forcing, seasonal water level anomalies, surge and in-Bay generated wind waves from the wind and pressure fields of a NWS forecast model, and tributary discharges from the Research Distributed Hydrologic Model (RDHM), developed by the NWS Office of Hydrologic Development. The flooding extent is determined by overlaying the resulting water levels onto a recently completed 2-m digital elevation model of the study area which best resolves the extensive levee and tidal marsh systems in the region. Here we present initial pilot results of hindcast winter storms in January 2010 and December 2012, where the flooding is driven by oceanic and fluvial factors respectively. We also demonstrate the feasibility of predicting flooding on an operational time scale that incorporates both atmospheric and hydrologic forcings.

  8. Effect of water conservation on water demands. [San Francisco Bay area

    Energy Technology Data Exchange (ETDEWEB)

    Maddaus, W.O.; Feuerstein, D.L.

    1979-09-01

    A new method for predicting long-range water demands was developed to quantify the post-drought effectiveness of water conservation in the San Francisco Bay area. The method relates water use and population density with employee density in the area. The projection model was used to test several alternative water conservation programs and the water savings were found to range from 4 to 16% by the year 2000. When the costs of water conservation were compared with those for building new water supply projects, it was concluded that water conservation is the most cost-effective source of water supply. 14 references.

  9. Lo spirito dorato. San Francisco e il Parco Crissy Field degli Hargreaves Associates

    Directory of Open Access Journals (Sweden)

    Enrica Dall’Ara

    2015-11-01

    Full Text Available Nel saggio si presenta il progetto di riqualificazione degli Hargreaves Associates per il waterfront della costa nord di San Francisco, un’ area dimessa dall’aviazione ed appartenente al Golden Gate National Recreational Area denominata Crissy Field. Il progetto si presenta sia come risposta chiara a specifiche necessità ambientali che come espressione di volontà estetiche ben misurate e si basa su un principio di conservazione del genius loci della metropoli, confrontandosi con lo status di landmark nazionale attribuito all’area nel 1962. 

  10. Remote sensing analysis of water quality in the San Francisco Bay-delta

    Science.gov (United States)

    Khorram, S.

    1979-01-01

    Water quality parameters in the San Francisco Bay-delta area using remotely sensed data combined with in situ data are investigated. The parameters included suspended solids, chlorophyll, turbidity, and electrical conductivity; the ocean color scanner (OCS) data were acquired from a NASA U-2 aircraft, and water quality samples were obtained from boats. It was concluded that areas with high biological activity were clearly discernible on enhanced imagery from OCS data, and it was impossible to locate such areas on aerial photography taken with conventional or infrared sensitive color films.

  11. Gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data release contains information on gravity cores that were collected by the U.S. Geological Survey in the area of San Pablo Bay and Carquinez Strait,...

  12. Handbook of Techniques and Guides for the Study of the San Francisco Bay-Delta-Estuary Complex, Part 2. Key to the Phytoplankton Phyla and Genera.

    Science.gov (United States)

    Helrich, Jane

    Project MER (Marine Ecology Research) is aimed at improving environmental education in the San Francisco Bay Area schools. This document is the second of a series of guides designed to help students and teachers gather data concerning the San Francisco Bay-Delta-Estuary Complex and to organize these data to make a contribution to the literature of…

  13. An introduction to the San Francisco Estuary tidal wetlands restoration series

    Directory of Open Access Journals (Sweden)

    Larry R. Brown

    2003-10-01

    Full Text Available Restoration of tidal wetlands may provide an important tool for improving ecological health and water management for beneficial uses of the San Francisco Estuary (hereafter “Estuary”. Given the large losses of tidal wetlands from San Francisco Bay and the Sacramento-San Joaquin Delta in the last 150 years, it seems logical to assume that restoring tidal wetlands will have benefits for a variety of aquatic and terrestrial native species that have declined during the same time period. However, many other changes have also occurred in the Estuary concurrent with the declines of native species. Other factors that might be important in species declines include the effects of construction of upstream dams, large and small water diversions within the Sacramento-San Joaquin Delta, agricultural pesticides, trace elements from industrial and agricultural activities, and invasions of alien species. Discussions among researchers, managers, and stakeholders have identified a number of uncertainties regarding the potential benefits of tidal wetland restoration. The articles of the Tidal Wetlands Restoration Series address four major issues of concern. Stated as questions, these are: 1. Will tidal wetland restoration enhance populations of native fishes? 2. Will wetland restoration increase rates of methylation of mercury? 3. Will primary production and other ecological processes in restored tidal wetlands result in net export of organic carbon to adjacent habitats, resulting in enhancement of the food web? Will the carbon produced contribute to the formation of disinfection byproducts when disinfected for use as drinking water? 4. Will restored tidal wetlands provide long-term ecosystem benefits that can be sustained in response to ongoing physical processes, including sedimentation and hydrodynamics? Reducing the uncertainty surrounding these issues is of critical importance because tidal wetland restoration is assumed to be a critical tool for enhancement

  14. An Introduction to the San Francisco Estuary Tidal Wetlands Restoration Series

    Directory of Open Access Journals (Sweden)

    Larry R. Brown

    2003-10-01

    Full Text Available Restoration of tidal wetlands may provide an important tool for improving ecological health and water management for beneficial uses of the San Francisco Estuary (hereafter “Estuary”. Given the large losses of tidal wetlands from San Francisco Bay and the Sacramento-San Joaquin Delta in the last 150 years, it seems logical to assume that restoring tidal wetlands will have benefits for a variety of aquatic and terrestrial native species that have declined during the same time period. However, many other changes have also occurred in the Estuary concurrent with the declines of native species. Other factors that might be important in species declines include the effects of construction of upstream dams, large and small water diversions within the Sacramento-San Joaquin Delta, agricultural pesticides, trace elements from industrial and agricultural activities, and invasions of alien species. Discussions among researchers, managers, and stakeholders have identified a number of uncertainties regarding the potential benefits of tidal wetland restoration. The articles of the Tidal Wetlands Restoration Series address four major issues of concern. Stated as questions, these are: 1. Will tidal wetland restoration enhance populations of native fishes? 2. Will wetland restoration increase rates of methylation of mercury? 3. Will primary production and other ecological processes in restored tidal wetlands result in net export of organic carbon to adjacent habitats, resulting in enhancement of the food web? Will the carbon produced contribute to the formation of disinfection byproducts when disinfected for use as drinking water? 4. Will restored tidal wetlands provide long-term ecosystem benefits that can be sustained in response to ongoing physical processes, including sedimentation and hydrodynamics? Reducing the uncertainty surrounding these issues is of critical importance because tidal wetland restoration is assumed to be a critical tool for

  15. Trace Elemental Analyses of Suspended Sediments in the San Francisco Estuary and its Tidal Marshes

    Science.gov (United States)

    Malamud-Roam, F. P.; Ingram, B. L.; Yang, W.; Collins, J.

    2004-12-01

    This research evaluates the trace elemental compositions of inorganic sediments in the San Francisco Bay estuary marshes over space and time. These sediments create and maintain the tidal marshes that surround the Sand Francisco Bay, yet a thorough analysis of the sources of these sediments remains understudied. Determining the sources of sediments is of interest because current mitigation and restoration projects around the Bay must consider whether the sediment supply will be sufficient for projects, or if opening diked wetlands to tidal flow will result in salt water intrusion further up-estuary (into the Delta). Results of trace element analyses of suspended sediments that pass through the Sacramento-San Joaquin Delta (the Delta) are compared with those of local watershed tributaries. Differences in bedrock lithology can be seen in the varying trace elemental concentrations; for example, K, Nd, Sm, Rb and Sr concentrations are significantly lower in the Sacramento river sediments than those of the San Joaquin river and can be used to differentiate further the Delta input. Results from marsh surface samples throughout the North Bay and preliminary results from 4 1-m long sediment cores collected along a transect of the Novato creek marsh (NCM) reflect local versus Delta sediment source patterns. The suspended sediment samples from the Sacramento and San Joaquin rivers and from local creeks reflect the end members of the sediment supply for local marshes. The marsh surface samples represent the most recent period (last few years or so) and reflect the extent of Delta influence into the estuary. Finally, the cores collected from the Novato creek marsh provide details on the gradient of dominant source supply (i.e., are the sediments well inland predominantly from the local watershed and how far does that influence extend downstream), as well as a history of how the sediment supply conditions have changed, comparing pre-Gold Rush and agriculture era (before about

  16. Deep Borehole Instrumentation Along San Francisco Bay Bridges: 1996 - 2003 and Strong Ground Motion Systhesis Along the San Francisco/Oakland Bay Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Hutchings, L; Foxall, W; Kasameyer, P; larsen, S; Hayek, C; Tyler-Turpin, C; Aquilino, J; Long, L

    2005-04-22

    As a result of collaboration between the Berkeley Seismographic Station, Lawrence Livermore National Laboratory, and Caltrans, instrument packages have been placed in bedrock in six boreholes and two surface sites along the San Francisco/Oakland Bay Bridge. Since 1996 over 200 local earthquakes have been recorded. Prior to this study few seismic recording instruments existed in bed-rock in San Francisco Bay. We utilized the data to perform analysis of ground motion variability, wave passage, site response, and up-and down-hole wave propagation along the Bay Bridge. We also synthesized strong ground motion at nine locations along the Bay Bridge. Key to these studies is LLNL's effort to exploit the information available in weak ground motions (generally from earthquakes < M=4.0) to enhance predictions of seismic hazards. We found that Yerba Island has no apparent site response at the surface relative to a borehole site. The horizontal to vertical spectral ratio method best revealed no site response, while the complex signal spectral ratio method had the lowest variance for spectral ratios and best predicted surface recordings when the borehole recording was used as input. Both methods identified resonances at about the same frequencies. Regional attenuation results in a significant loss of high frequencies in both surface and borehole recordings. Records are band limited at near 3 Hz. Therefore a traditional rock outcrop site response, flat to high frequency in displacement, is not available. We applied a methodology to predict and synthesize strong ground motion along the San Francisco/Oakland Bay Bridge from a M=7.25 earthquake along the Hayward fault, about12 km distant. We synthesized for three-components and broad-band (0.0-25.0 Hz) ground motion accelerations, velocities, and displacements. We examined two different possible rupture scenarios, a ''mean'' and ''one standard deviation'' model. We combined the high

  17. Effects of Climate Change on Range Forage Production in the San Francisco Bay Area

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R.

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California’s annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area. PMID:23472102

  18. Three-dimensional Modeling of Tidal Hydrodynamics in the San Francisco Estuary

    Directory of Open Access Journals (Sweden)

    Edward S. Gross

    2010-01-01

    Full Text Available Simulations of circulation in the San Francisco Estuary were performed with the three-dimensional TRIM3D hydrodynamic model using a generic length scale turbulence closure. The model was calibrated to reproduce observed tidal elevations, tidal currents, and salinity observations in the San Francisco Estuary using data collected during 1996-1998, a period of high and variable freshwater flow. It was then validated for 1994-1995, with emphasis on spring of 1994, a period of intensive data collection in the northern estuary. The model predicts tidal elevations and tidal currents accurately, and realistically predicts salinity at both the seasonal and tidal time scales. The model represents salt intrusion into the estuary accurately, and therefore accurately represents the salt balance. The model’s accuracy is adequate for its intended purposes of predicting salinity, analyzing gravitational circulation, and driving a particle-tracking model. Two applications were used to demonstrate the utility of the model. We estimated the components of the longitudinal salt flux and examined their dependence on flow conditions, and compared predicted salt intrusion with estimates from two empirical models.

  19. Empirical model of Skeletonema costatum photosynthetic rate, with applications in the San Francisco Bay estuary

    Science.gov (United States)

    Cloern, J.E.

    1978-01-01

    An empirical model of Skeletonema costatum photosynthetic rate is developed and fit to measurements of photosynthesis selected from the literature. Because the model acknowledges existence of: 1) a light-temperature interaction (by allowing optimum irradiance to vary with temperature), 2) light inhibition, 3) temperature inhibition, and 4) a salinity effect, it accurately estimates photosynthetic rates measured over a wide range of temperature, light intensity, and salinity. Integration of predicted instantaneous rate of photosynthesis with time and depth yields daily net carbon assimilation (pg C cell-1 day-1) in a mixed layer of specified depth, when salinity, temperature, daily irradiance and extinction coefficient are known. The assumption of constant carbon quota (pg C cell-1) allows for prediction of mean specific growth rate (day-1), which can be used in numerical models of Skeletonema costatum population dynamics. Application of the model to northern San Francisco Bay clearly demonstrates the limitation of growth by low light availability, and suggests that large population densities of S. costatum observed during summer months are not the result of active growth in the central deep channels (where growth rates are consistently predicted to be negative). But predicted growth rates in the lateral shallows are positive during summer and fall, thus offering a testable hypothesis that shoals are the only sites of active population growth by S. costatum (and perhaps other neritic diatoms) in the northern reach of San Francisco Bay. ?? 1978.

  20. Biological communities in San Francisco Bay track large-scale climate forcing over the North Pacific

    Science.gov (United States)

    Cloern, James E.; Hieb, Kathryn A.; Jacobson, Teresa; Sansó, Bruno; Di Lorenzo, Emanuele; Stacey, Mark T.; Largier, John L.; Meiring, Wendy; Peterson, William T.; Powell, Thomas M.; Winder, Monika; Jassby, Alan D.

    2010-11-01

    Long-term observations show that fish and plankton populations in the ocean fluctuate in synchrony with large-scale climate patterns, but similar evidence is lacking for estuaries because of shorter observational records. Marine fish and invertebrates have been sampled in San Francisco Bay since 1980 and exhibit large, unexplained population changes including record-high abundances of common species after 1999. Our analysis shows that populations of demersal fish, crabs and shrimp covary with the Pacific Decadal Oscillation (PDO) and North Pacific Gyre Oscillation (NPGO), both of which reversed signs in 1999. A time series model forced by the atmospheric driver of NPGO accounts for two-thirds of the variability in the first principal component of species abundances, and generalized linear models forced by PDO and NPGO account for most of the annual variability of individual species. We infer that synchronous shifts in climate patterns and community variability in San Francisco Bay are related to changes in oceanic wind forcing that modify coastal currents, upwelling intensity, surface temperature, and their influence on recruitment of marine species that utilize estuaries as nursery habitat. Ecological forecasts of estuarine responses to climate change must therefore consider how altered patterns of atmospheric forcing across ocean basins influence coastal oceanography as well as watershed hydrology.

  1. Modeling the periodic stratification and gravitational circulation in San Francisco Bay, California

    Science.gov (United States)

    Cheng, Ralph T.; Casulli, Vincenzo

    1996-01-01

    A high resolution, three-dimensional (3-D) hydrodynamic numerical model is applied to San Francisco Bay, California to simulate the periodic tidal stratification caused by tidal straining and stirring and their long-term effects on gravitational circulation. The numerical model is formulated using fixed levels in the vertical and uniform computational mesh on horizontal planes. The governing conservation equations, the 3-D shallow water equations, are solved by a semi-implicit finite-difference scheme. Numerical simulations for estuarine flows in San Francisco Bay have been performed to reproduce the hydrodynamic properties of tides, tidal and residual currents, and salt transport. All simulations were carried out to cover at least 30 days, so that the spring-neap variance in the model results could be analyzed. High grid resolution used in the model permits the use of a simple turbulence closure scheme which has been shown to be sufficient to reproduce the tidal cyclic stratification and well-mixed conditions in the water column. Low-pass filtered 3-D time-series reveals the classic estuarine gravitational circulation with a surface layer flowing down-estuary and an up-estuary flow near the bottom. The intensity of the gravitational circulation depends upon the amount of freshwater inflow, the degree of stratification, and spring-neap tidal variations.

  2. Genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay

    Science.gov (United States)

    Duda, T. F.

    1994-01-01

    The genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay was described using starch gel electrophoresis at eight presumptive loci. Specimens were taken from five environmentally distinct sites located throughout the bay. The population maintains a high degree of genetic variation, with a mean heterozygosity of 0.295, a mean polymorphism of 0.75, and an average of 3.70 alleles per locus. The population is genetically homogeneous, as evidenced from genetic distance values and F-statistics. However, heterogeneity of populations was indicated from a contingency chi-square test. Significant deviations from Hardy-Weinberg equilibrium and heterozygote deficiencies were found at the Lap-1 locus for all populations and at the Lap-2 locus for a single population. High levels of variability could represent a universal characteristic of invading species, the levels of variability in the source population(s), and/or the dynamics of the introduction. Lack of differentiation between subpopulations may be due to the immaturity of the San Francisco Bay population, the “general purpose” phenotype genetic strategy of the species, high rates of gene flow in the population, and/or the selective neutrality of the loci investigated.

  3. Effects of climate change on range forage production in the San Francisco Bay Area.

    Directory of Open Access Journals (Sweden)

    Rebecca Chaplin-Kramer

    Full Text Available The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  4. A Pilot Study of Retail 'Vape Shops' in the San Francisco Bay Area.

    Science.gov (United States)

    Burbank, Andrea D; Thrul, Johannes; Ling, Pamela M

    2016-01-01

    The use of electronic cigarettes or vape devices is increasing, and products are evolving rapidly. This study assessed retail vape shops in the San Francisco Bay Area to describe store characteristics, products offered, advertisements and health claims, as well as employees' perceptions of their customers' demographics, and practices to support smoking cessation. We conducted store audits of shops that exclusively sell vape devices with physical addresses in San Francisco and Alameda counties (n=23, response rate 72%) and interviewed vape shop owners/employees. While all stores carried second and third generation vape devices, 83% of stores did not carry first generation devices. Employees estimated the majority of their customers bought devices for smoking cessation or to replace tobacco, and a small minority purchased for first-time recreational use. Employees most frequently recommended dosing nicotine based on usual cigarette consumption, adjusting doses based on "throat hit" or cravings, use of a second or third generation e-cigarette, and encouraged customers to experiment and customize to "whatever works for you" as smoking cessation advice. Vape shops report a significant number of their customers are interested in smoking cessation, and employees are giving smoking cessation advice. A subpopulation of customers includes some nicotine novices. Studies of vape shops should include both observations and interviews with employees in order to detect important informal practices that may differ from posted signs or printed advertising. These practices include cessation counseling, product claims, and custom discount prices or bargaining.

  5. A Pilot Study of Retail ‘Vape Shops’ in the San Francisco Bay Area

    Science.gov (United States)

    Burbank, Andrea D; Thrul, Johannes; Ling, Pamela M

    2016-01-01

    INTRODUCTION The use of electronic cigarettes or vape devices is increasing, and products are evolving rapidly. This study assessed retail vape shops in the San Francisco Bay Area to describe store characteristics, products offered, advertisements and health claims, as well as employees’ perceptions of their customers’ demographics, and practices to support smoking cessation. METHODS We conducted store audits of shops that exclusively sell vape devices with physical addresses in San Francisco and Alameda counties (n=23, response rate 72%) and interviewed vape shop owners/employees. RESULTS While all stores carried second and third generation vape devices, 83% of stores did not carry first generation devices. Employees estimated the majority of their customers bought devices for smoking cessation or to replace tobacco, and a small minority purchased for first-time recreational use. Employees most frequently recommended dosing nicotine based on usual cigarette consumption, adjusting doses based on “throat hit” or cravings, use of a second or third generation e-cigarette, and encouraged customers to experiment and customize to “whatever works for you” as smoking cessation advice. CONCLUSIONS Vape shops report a significant number of their customers are interested in smoking cessation, and employees are giving smoking cessation advice. A subpopulation of customers includes some nicotine novices. Studies of vape shops should include both observations and interviews with employees in order to detect important informal practices that may differ from posted signs or printed advertising. These practices include cessation counseling, product claims, and custom discount prices or bargaining. PMID:28393129

  6. Effects of climate change on range forage production in the San Francisco Bay Area.

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  7. Distribution and Invasion Potential of Limonium ramosissimum subsp. provinciale in San Francisco Estuary Salt Marshes

    Directory of Open Access Journals (Sweden)

    Gavin Archbald

    2014-06-01

    Full Text Available Non-native sea lavenders (Limonium spp. are invasive in salt marshes of southern California and were first documented in the San Francisco Estuary (the estuary in 2007. In this study, we mapped distributions of L. ramosissimum subsp. provinciale (LIRA and L. duriusculum within the estuary and investigated how the invasion potential of the more common species, LIRA, varies with elevation and edaphic conditions. We contacted colleagues and conducted field searches to find and then map sea lavender populations. In addition, we measured LIRA’s elevational range at three salt marshes. Across this range we measured (1 soil properties: salinity, moisture, bulk density, and texture; and (2 indicators of invasion potential: LIRA size, seed production, percent cover, spread (over 1 year, recruitment, and competition with native halophytes (over 6 months. We found LIRA in 15,144 m2 of upper salt marsh habitat in central and south San Francisco bays and L. duriusculum in 511 m2 in Richardson and San Pablo bays. LIRA was distributed from mean high water (MHW to 0.42 m above mean higher high water (MHHW. In both spring and summer, soil moisture and salinity were lowest at higher elevations within LIRA’s range, which corresponded with greater rosette size, inflorescence and seed production (up to 17,400 seeds per plant, percent cover, and recruitment. LIRA cover increased on average by 11% in 1 year across marshes and elevations. Cover of the native halophytes Salicornia pacifica, Jaumea carnosa, and Distichlis spicata declined significantly at all elevations if LIRA were present in plots (over a 6-month, fall–winter period. Results suggest LIRA’s invasion potential is highest above MHHW where salinity and moisture are lower, but that LIRA competes with native plants from MHW to above MHHW. We recommend removal efforts with emphasis on the salt marsh-terrestrial ecotone where LIRA seed output is highest.

  8. Preliminary Results from Real-Time GPS Monitoring in the San Francisco Bay Area

    Science.gov (United States)

    Langbein, J. O.; Guillemot, C.

    2013-12-01

    A web-based monitoring system has been implemented to display displacement estimates in real-time for various combinations of USGS, Plate Boundary Observatory (PBO) and Bay Area Regional Deformation (BARD) network stations in the San Francisco Bay area. Tools and utilities developed in-house are used to visually analyze the quality of estimated positions and gain a better understanding of the challenges involved in integrating displacement data into earthquake early warning (EEW) algorithms. Comparisons of results between differential and precise position estimates obtained from a variety of software packages have led to a closer examination of the epoch-per-epoch latencies, or delays with which those estimates are generated. For example, although position estimates from precise point positioning, with ambiguity resolution, (PPP-AR) computed in real-time are reasonably stable over short-time scales, latencies of 50 seconds or more currently preclude their useful incorporation into EEW algorithms. On the other hand, the latencies for differential position range between less than a second to 10 seconds. The large latencies for PPP-AR are partly due to the fact that displacement estimates obtained from GPS cannot yet be generated at the source but must rely on centralized processing that incorporates instantaneous clock corrections which, in turn must be obtained from external agencies. The latencies, however, are not as critical for the study of post-seismic deformation that occurs minutes to hours following an earthquake. Computation of the power spectra of time series provides a quantitative means to compare the precision of estimated positions that are obtained from various software that process the data in real-time. To first order, the current set of processing algorithms, including those using differential position and PPP-AR, provides nearly equal performance in terms of temporal correlations which is represented by their power spectra. At the shortest periods

  9. Association between Diabetes Mellitus and Tuberculosis in United States-Born and Foreign-Born Populations in San Francisco

    Science.gov (United States)

    Suwanpimolkul, Gompol; Grinsdale, Jennifer A.; Jarlsberg, Leah G.; Higashi, Julie; Osmond, Dennis H.; Hopewell, Philip C.; Kato-Maeda, Midori

    2014-01-01

    Setting The impact of diabetes on tuberculosis in United States and foreign-born populations in San Francisco has not been studied. Objective To determine the characteristics, prevalence and temporal trends of diabetes in US and foreign-born persons attending the San Francisco Tuberculosis Clinic. Design We analyzed data from individuals seeking medical attention at the San Francisco Tuberculosis Clinic. We included patients with diagnosis of tuberculosis, latent infection, or not infected with Mycobacterium tuberculosis. We assessed the temporal trend and the characteristics of individuals with and without diabetes. Result Between 2005 and 2012, there were 4371 (19.0%) individuals without evidence of tuberculosis infection, 17,856 (77.6%) with latent tuberculosis, and 791 (3.4%) with tuberculosis. 66% were born in the United States, China, Mexico, and the Philippines. The prevalence of diabetes was the highest among individuals with tuberculosis and increased during the study period. Patients with tuberculosis and diabetes were more likely to be male, older than 45 years and born in the Philippines. There was a disproportionate association of TB and DM relative to LTBI and DM among Filipinos in individuals older than 45 years old. Conclusions Our data suggest that Filipinos older than 45 years old are more likely to have tuberculosis probably due to a higher prevalence of diabetes. In San Francisco, tuberculosis-screening programs in individuals with diabetes and latent tuberculosis may be beneficial in patients older than 45 years old especially from the Philippines. PMID:25478954

  10. Identifying Telemedicine Services to Improve Access to Specialty Care for the Underserved in the San Francisco Safety Net

    Directory of Open Access Journals (Sweden)

    Ken Russell Coelho

    2011-01-01

    Full Text Available Safety-net settings across the country have grappled with providing adequate access to specialty care services. San Francisco General Hospital and Trauma Center, serving as the city's primary safety-net hospital, has also had to struggle with the same issue. With Healthy San Francisco, the City and County of San Francisco's Universal Healthcare mandate, the increased demand for specialty care services has placed a further strain on the system. With the recent passage of California Proposition 1D, infrastructural funds are now set aside to assist in connecting major hospitals with primary care clinics in remote areas all over the state of California, using telemedicine. Based on a selected sample of key informant interviews with local staff physicians, this study provides further insight into the current process of e-referral which uses electronic communication for making referrals to specialty care. It also identifies key services for telemedicine in primary and specialty care settings within the San Francisco public health system. This study concludes with proposals for a framework that seek to increase collaboration between the referring primary care physician and specialist, to prioritize institution of these key services for telemedicine.

  11. MEDIA ADVISORY: EPA Administrator joins San Francisco Bay government agencies to celebrate nations largest solar energy partnership

    Science.gov (United States)

    SAN FRANCISCO - On May 13, U.S. EPA Administrator Gina McCarthy will join Alameda County to recognize the largest collaborative in the nation among government agencies to site renewable energy at their facilities. Administrator McCarthy, the federal

  12. 78 FR 34582 - Safety Zone; Fourth of July Fireworks, City of Sausalito, San Francisco Bay, Sausalito, CA

    Science.gov (United States)

    2013-06-10

    ... the Captain of the Port, San Francisco area of responsibility during the dates and times noted below. This action is necessary to protect life and property of the maritime public from the hazards... direction. The PATCOM is empowered to forbid entry into and control the regulated area. The PATCOM shall be...

  13. Association between diabetes mellitus and tuberculosis in United States-born and foreign-born populations in San Francisco.

    Science.gov (United States)

    Suwanpimolkul, Gompol; Grinsdale, Jennifer A; Jarlsberg, Leah G; Higashi, Julie; Osmond, Dennis H; Hopewell, Philip C; Kato-Maeda, Midori

    2014-01-01

    The impact of diabetes on tuberculosis in United States and foreign-born populations in San Francisco has not been studied. To determine the characteristics, prevalence and temporal trends of diabetes in US and foreign-born persons attending the San Francisco Tuberculosis Clinic. We analyzed data from individuals seeking medical attention at the San Francisco Tuberculosis Clinic. We included patients with diagnosis of tuberculosis, latent infection, or not infected with Mycobacterium tuberculosis. We assessed the temporal trend and the characteristics of individuals with and without diabetes. Between 2005 and 2012, there were 4371 (19.0%) individuals without evidence of tuberculosis infection, 17,856 (77.6%) with latent tuberculosis, and 791 (3.4%) with tuberculosis. 66% were born in the United States, China, Mexico, and the Philippines. The prevalence of diabetes was the highest among individuals with tuberculosis and increased during the study period. Patients with tuberculosis and diabetes were more likely to be male, older than 45 years and born in the Philippines. There was a disproportionate association of TB and DM relative to LTBI and DM among Filipinos in individuals older than 45 years old. Our data suggest that Filipinos older than 45 years old are more likely to have tuberculosis probably due to a higher prevalence of diabetes. In San Francisco, tuberculosis-screening programs in individuals with diabetes and latent tuberculosis may be beneficial in patients older than 45 years old especially from the Philippines.

  14. Comparative analysis of long-term chlorophyll data with generalized additive model - San Francisco Bay and St. Lucie Estuary

    Science.gov (United States)

    The health of estuarine ecosystems is often influenced by hydraulic and nutrient loading from upstream watersheds. We examined four decades of monitoring data of nutrient export into the Indian River Lagoon and San Francisco Bay, both of which have received considerable attentio...

  15. Density and elevational distribution of the San Francisco Peaks ragwort, Packera franciscana (Asteraceae), a threatened single-mountain endemic

    Science.gov (United States)

    James F. Fowler; Carolyn Hull Sieg

    2011-01-01

    Packera franciscana (Greene) W. A. Weber and A. Love is endemic to treeline and alpine habitats of the San Francisco Peaks, Arizona, USA and was listed as a threatened species under the Endangered Species Act in 1983. Species abundance data are limited in scope, yet are critical for recovery of the species, especially in light of predictions of its future extinction...

  16. Risk behaviors of Filipino methamphetamine users in San Francisco: implications for prevention and treatment of drug use and HIV.

    OpenAIRE

    Nemoto, Tooru; Operario, Don; Soma, Toho

    2002-01-01

    OBJECTIVE: This study describes the demographics, HIV risk and drug use behaviors, and psychosocial status of Filipino American methamphetamine users in the San Francisco Bay area. METHODS: Individual interviews were conducted with 83 Filipino American methamphetamine users, recruited through snowball sampling methods. A structured survey questionnaire included measures of drug use behaviors, HIV-related sexual behaviors, psychosocial factors, and demographics. RESULTS: Filipino methamphetami...

  17. Deposition, erosion, and bathymetric change in South San Francisco Bay: 1858-1983

    Science.gov (United States)

    Foxgrover, Amy C.; Higgins, Shawn A.; Ingraca, Melissa K.; Jaffe, Bruce E.; Smith, Richard E.

    2004-01-01

    Since the California Gold Rush of 1849, sediment deposition, erosion, and the bathymetry of South San Francisco Bay have been altered by both natural processes and human activities. Historical hydrographic surveys can be used to assess how this system has evolved over the past 150 years. The National Ocean Service (NOS) (formerly the United States Coast and Geodetic Survey (USCGS), collected five hydrographic surveys of South San Francisco Bay from 1858 to 1983. Analysis of these surveys enables us to reconstruct the surface of the bay floor for each time period and quantify spatial and temporal changes in deposition, erosion, and bathymetry. The creation of accurate bathymetric models involves many steps. Sounding data was obtained from the original USCGS and NOS hydrographic sheets and were supplemented with hand drawn depth contours. Shorelines and marsh areas were obtained from topographic sheets. The digitized soundings and shorelines were entered into a Geographic Information System (GIS), and georeferenced to a common horizontal datum. Using surface modeling software, bathymetric grids with a horizontal resolution of 50 m were developed for each of the five hydrographic surveys. Prior to conducting analyses of sediment deposition and erosion, we converted all of the grids to a common vertical datum and made adjustments to correct for land subsidence that occurred from 1934 to 1967. Deposition and erosion that occurred during consecutive periods was then computed by differencing the corrected grids. From these maps of deposition and erosion, we calculated volumes and rates of net sediment change in the bay. South San Francisco Bay has lost approximately 90 x 106 m3 of sediment from 1858 to 1983; however within this timeframe there have been periods of both deposition and erosion. During the most recent period, from 1956 to 1983, sediment loss approached 3 x 106 m3/yr. One of the most striking changes that occurred from 1858 to 1983 was the conversion of more

  18. Talus Lex: Regulatory Approaches to Reducing Mercury Concentrations in San Francisco Bay Fish.

    Science.gov (United States)

    Abu-Saba, D. E.; Flegal, D. R.; Ganguli, P. M.; Whyte, D. C.; Mumley, D. E.; Mason, D. P.

    2001-12-01

    The history of mercury in California is recorded in the sediments of San Francisco Bay. The Bay is downstream of 40 percent of the land area of California. Its watershed receives 80 percent of the rainfall in the State, because it rains more in the north. Three billion kilograms of sediments are annually flushed from the Central Valley watershed and deposited in San Francisco Bay. Because mercury preferentially binds to sediments, we calculate mercury loads to the Bay by considering how various sources affect mercury concentrations in Bay sediments. During and after the Gold Rush, over seventy thousand tons of mercury was produced in Coast Range cinnabar mines. Much of this mercury was used as quicksilver to extract gold from placer formations in the Sierra foothills, and later in the production of munitions, electronics, health care and commercial products. Today, we can see the legacy of mining sources, from both remote and local watersheds, superimposed on air deposition, the climate and geography of California, heavily managed water supply and flood control projects, wetland restoration and rehabilitation, urbanization, wastewaster discharge and water reclamation. We already regulate wastewater and urban runoff through issuance of permits and waste discharge requirements. We can regulate mercury inputs from inoperative mines by demonstrating the link between mercury-polluted sediments and violation of existing numeric water quality objectives. We can use the same approach to regulate the disposal of mercury-containing electronic devices. But to reduce mercury levels in fish, we will also have to consider controllable water quality factors that promote mercury methylation in the aquatic ecosystem. Some of these water quality factors are already subject to regulation. For example, we can show that mercury methylation in the northern reach of the Bay increases when dissolved oxygen drops below 6 mg/L; current regulations require dissolved oxygen concentrations of

  19. Interannual variability in dissolved inorganic nutrients in northern San Francisco Bay estuary

    Science.gov (United States)

    Peterson, D.H.; Smith, R.E.; Hager, S.W.; Harmon, D.D.; Herndon, R.E.; Schemel, L.E.

    1985-01-01

    Nearly two decades of seasonal dissolved inorganic nutrient-salinity distributions in northern San Francisco Bay estuary (1960-1980) illustrate interannual variations in effects of river flow (a nutrient source) and phytoplankton productivity (a nutrient sink). During winter, nutrient sources dominate the nutrient-salinity distribution patterns (nutrients are at or exceed conservative mixing concentrations). During summer, however, the sources and sinks are in close competition. In summers of wet years, the effects of increased river flow often dominate the nutrient distributions (nutrients are at or less than conservative mixing concentrations), whereas in summers of dry years, phytoplankton productivity dominates (the very dry years 1976-1977 were an exception for reasons not yet clearly known). Such source/sink effects also vary with chemical species. During summer the control of phytoplankton on nutrient distributions is apparently strongest for ammonium, less so for nitrate and silica, and is the least for phosphate. Furthermore, the strength of the silica sink (diatom productivity) is at a maximum at intermediate river flows. This relation, which is in agreement with other studies based on phytoplankton abundance and enumeration, is significant to the extent that diatoms are an important food source for herbivores. The balance or lack of balance between nutrient sources and sinks varies from one estuary to another just as it can from one year to another within the same estuary. At one extreme, in some estuaries river flow dominates the estuarine dissolved inorganic nutrient distributions throughout most of the year. At the other extreme, phytoplankton productivity dominates. In northern San Francisco Bay, for example, the phytoplankton nutrient sink is not as strong as in less turbid estuaries. In this estuary, however, river effects, which produce or are associated with near-conservative nutrient distributions, are strong even at flows less than mean

  20. Tap water isotopes reveal the San Francisco Bay Area's plumbing and responses to a major drought

    Science.gov (United States)

    Tipple, B. J.; Jameel, M. Y.; Chau, T. H.; Mancuso, C. J.; Bowen, G. J.; Dufour, A.; Chesson, L. A.; Ehleringer, J. R.

    2016-12-01

    Water availability and sustainability in the Western United States is a major flashpoint among expanding communities, growing industries, and productive agricultural lands. This issue came to a head in 2015 in the State of California, when the State mandated a 25% reduction in urban water use following a multi-year drought that significantly depleted water resources. The demands for and challenges in supplying water are only expected to intensify as climate perturbations, such as the 2012-2015 California Drought, become more common. As a consequence, there is an increased need to understand linkages between population centers, water transport and usage, and the impacts of climate change on water resources and infrastructure. To better understand these relationships within a megalopolis in the Western United States, we collected and analyzed 723 tap waters from the San Francisco Bay Area during seven collection campaigns across 21 months during 2013-2015. San Francisco Bay Area was selected as it has well-known water management strategies and its water resources were dramatically affected by the 2012-2105 drought. Consistent with known water management strategies and previous reports of tap water isotope values, we found large spatiotemporal variations in the δ2H and δ18O values of tap waters, indicative of complex water transport systems and municipality-scale management decisions. We observed δ2H and δ18O values of tap water consistent with waters originating from snowmelt from the Sierra Nevada Mountains, local precipitation, ground water, and partially evaporated reservoir sources. A cluster analysis of measured tap water data grouped waters from 43 static sampling sites that were associated with specific water utility providers within the San Francisco Bay Area and known management practices. Water management responses to the drought, such as source switching, bringing in new sources, and conservation, could be observed within the isotope data from each of

  1. The Dinner Menu: Spatial Distribution of Organic Carbon Composition Across the San Francisco Bay-Delta

    Science.gov (United States)

    Harfmann, J.; Hernes, P.; Bergamaschi, B. A.

    2016-12-01

    The San Francisco Bay-Delta is a dynamic tidal system with multiple sources of carbon, both autochthonous (e.g. phytoplankton, submersed or floating aquatic vegetation, or non-phytoplankton microalgae) and allochthonous (e.g. riverine detritus, agricultural drainage, and urban runoff). Spatial variability in organic carbon (OC) sources translates into varying degrees of food quantity and quality for the aquatic food web, and yet surprisingly little is known about the implications of carbon source variability on the health of zooplankton populations, which form the base of the lower food chain. Particulate organic carbon (POC) is a critical component of zooplankton diet, and with the assistance of the microbial loop, dissolved organic carbon (DOC) may supplement their food. As part of a larger study linking OC sources with zooplankton growth, we collected water samples along a transect from San Pablo Bay to the Sacramento-San Joaquin Delta. Samples were analyzed for bulk POC and DOC, lignin, chlorophyll a, δ13C, and δ15N. Feeding experiments with the calanoid copepod Eurytemora affinis will be conducted in order to assess the relative bioavailability of collected OC across the transect.

  2. Ground motion modeling of the 1906 San Francisco earthquake II: Ground motion estimates for the 1906 earthquake and scenario events

    Energy Technology Data Exchange (ETDEWEB)

    Aagaard, B; Brocher, T; Dreger, D; Frankel, A; Graves, R; Harmsen, S; Hartzell, S; Larsen, S; McCandless, K; Nilsson, S; Petersson, N A; Rodgers, A; Sjogreen, B; Tkalcic, H; Zoback, M L

    2007-02-09

    We estimate the ground motions produced by the 1906 San Francisco earthquake making use of the recently developed Song et al. (2008) source model that combines the available geodetic and seismic observations and recently constructed 3D geologic and seismic velocity models. Our estimates of the ground motions for the 1906 earthquake are consistent across five ground-motion modeling groups employing different wave propagation codes and simulation domains. The simulations successfully reproduce the main features of the Boatwright and Bundock (2005) ShakeMap, but tend to over predict the intensity of shaking by 0.1-0.5 modified Mercalli intensity (MMI) units. Velocity waveforms at sites throughout the San Francisco Bay Area exhibit characteristics consistent with rupture directivity, local geologic conditions (e.g., sedimentary basins), and the large size of the event (e.g., durations of strong shaking lasting tens of seconds). We also compute ground motions for seven hypothetical scenarios rupturing the same extent of the northern San Andreas fault, considering three additional hypocenters and an additional, random distribution of slip. Rupture directivity exerts the strongest influence on the variations in shaking, although sedimentary basins do consistently contribute to the response in some locations, such as Santa Rosa, Livermore, and San Jose. These scenarios suggest that future large earthquakes on the northern San Andreas fault may subject the current San Francisco Bay urban area to stronger shaking than a repeat of the 1906 earthquake. Ruptures propagating southward towards San Francisco appear to expose more of the urban area to a given intensity level than do ruptures propagating northward.

  3. BRICKS, BRANDING, AND THE EVERYDAY: DEFINING GREATNESS AT THE UNITED NATIONS PLAZA IN SAN FRANCISCO

    Directory of Open Access Journals (Sweden)

    Georgia Lindsay

    2017-07-01

    Full Text Available After over a decade of reports, designs, and public outreach, the United Nations Plaza in San Francisco was dedicated in 1976. Using historical documents such as government reports, design guidelines, letters, meeting minutes, and newspaper articles from archives, I argue that while the construction of the UN Plaza has failed to completely transform the social and economic life of the area, it succeeds in creating a genuinely public space. The history of the UN Plaza can serve both as a cautionary tale for those interested in changing property values purely through changing design, and as a standard of success in making a space used by a true cross-section of urban society.

  4. Bathymetry and digital elevation models of Coyote Creek and Alviso Slough, South San Francisco Bay, California

    Science.gov (United States)

    Foxgrover, Amy C.; Finlayson, David P.; Jaffe, Bruce E.; Fregoso, Theresa A.

    2011-01-01

    In 2010 the U.S. Geological Survey (USGS), Coastal and Marine Geology Program completed three cruises to map the bathymetry of the main channel and shallow intertidal mudflats in the southernmost part of south San Francisco Bay. The three surveys were merged to generate comprehensive maps of Coyote Creek (from Calaveras Point east to the railroad bridge) and Alviso Slough (from the bay to the town of Alviso) to establish baseline bathymetry prior to the breaching of levees adjacent to Alviso and Guadalupe Sloughs as part of the South Bay Salt Pond Restoration Project http://www.southbayrestoration.org. Since 2010 we have conducted four additional surveys to monitor bathymetric change in this region as restoration progresses.

  5. Estimating methane emissions from biological and fossil-fuel sources in the San Francisco Bay Area

    Science.gov (United States)

    Jeong, Seongeun; Cui, Xinguang; Blake, Donald R.; Miller, Ben; Montzka, Stephen A.; Andrews, Arlyn; Guha, Abhinav; Martien, Philip; Bambha, Ray P.; LaFranchi, Brian; Michelsen, Hope A.; Clements, Craig B.; Glaize, Pierre; Fischer, Marc L.

    2017-01-01

    We present the first sector-specific analysis of methane (CH4) emissions from the San Francisco Bay Area (SFBA) using CH4 and volatile organic compound (VOC) measurements from six sites during September - December 2015. We apply a hierarchical Bayesian inversion to separate the biological from fossil-fuel (natural gas and petroleum) sources using the measurements of CH4 and selected VOCs, a source-specific 1 km CH4 emission model, and an atmospheric transport model. We estimate that SFBA CH4 emissions are 166-289 Gg CH4/yr (at 95% confidence), 1.3-2.3 times higher than a recent inventory with much of the underestimation from landfill. Including the VOCs, 82 ± 27% of total posterior median CH4 emissions are biological and 17 ± 3% fossil fuel, where landfill and natural gas dominate the biological and fossil-fuel CH4 of prior emissions, respectively.

  6. Masculinity and undocumented labor migration: injured latino day laborers in San Francisco

    Science.gov (United States)

    Walter, Nicholas; Bourgois, Philippe; Loinaz, H. Margarita

    2009-01-01

    Drawing on data collected through clinical practice and ethnographic fieldwork, this study examines the experience of injury, illness and disability among undocumented Latino day laborers in San Francisco. We demonstrate how constructions of masculine identity organize the experience of embodied social suffering among workers who are rendered vulnerable by the structural conditions of undocumented immigrant status. Theoretical concepts from critical medical anthropology and gender studies extend the scholarly analysis of structural violence beyond the primarily economic to uncover how it is embodied at the intimate level as a gendered experience of personal and familial crisis, involving love, respect, betrayal and patriarchal failure. A clinical ethnographic focus on socially structured patriarchal suffering elucidates the causal relationship between macro-forces and individual action with a fuller appreciation of the impact of culture and everyday lived experience. PMID:15210088

  7. Coastal Processes and Geomorphology along Crissy Beach and Inside San Francisco's Golden Gate

    Science.gov (United States)

    George, D. A.; Erikson, L. H.; Barnard, P. L.; Battalio, B.; Elias, E.; Hansen, J. E.; Sheehan, L. R.; White, L. A.

    2011-12-01

    The Golden Gate inlet to San Francisco Bay is a highly dynamic zone for sediment transport and geomorphic patterns. The behavior of the coastline has historically not been considered during land use planning, leading to a heavily manipulated shoreline in areas such as Ocean Beach, Crissy Field and other portions of the northern shore of San Francisco. Understanding of the regional and local coastal processes is even more important for future land-use planning and habitat restoration as sea level rises. The goal of this study is to present a summary of the coastal dynamics that govern the geomorphology of Crissy Field Beach and Marsh area, and estimate the future shore response to sea level rise. The Crissy Field marsh restoration in the late 1990s marked a new stage of studying coastal processes in this area of the Golden Gate Littoral Cell. For the past decade, the USGS and ESA PWA have conducted hydrodynamic, sediment transport, and geomorphic investigations extending from Ocean Beach to Crissy Marsh. USGS work has been driven by understanding the long-term function of the marsh while ESA PWA has focused on applying science to address coastal engineering and shoreline protection issues. We present a synthesis of this body of work as an example of successful public-private collaboration on coastal sciences. Several datasets were combined to characterize the region's dynamism. The local wave climate includes short period waves generated from local winds blowing over San Francisco Bay and longer period waves (swell) that arrive at Crissy Field from distant sources through the Golden Gate entrance. Tidal current data and model simulations indicate the presence of a residual circulation cell with ebb -dominance (eastward flow) offshore of Crissy Beach and a weaker westward current in the very nearshore region. Cross-shore transects of bathymetry and topography from 1947, 1978, 1997, 2007 and 2008 suggest patterns of erosion and deposition patterns occur on decadal

  8. San Francisco's Pioneer Mother Monument: maternalism, racial order, and the politics of memorialization, 1907–1915.

    Science.gov (United States)

    Frink, Brenda D

    2012-01-01

    The 1907–1915 campaign to create San Francisco's Pioneer Mother Monument provides both a case study of conservative uses of maternalism and a window into the political mutability of maternalist rhetoric. Ella Sterling Mighels, a pioneer descendant, utilized the monument campaign to promote white women's moral influence over middle-class men, to argue against Asian immigration and labor unrest, and to inculcate old-fashioned moral values among urban children. Although some of Mighels's contemporaries cited pioneer mothers as proof of women's fitness for suffrage, Mighels herself used the pioneer mother to argue against suffrage. The final statue, created by the sculptor Charles Grafly, failed to encapsulate Mighels's multivalent political message and to express her ideals about gender, race, class, and morality.

  9. Growth requirements of san francisco sour dough yeasts and bakers' yeast.

    Science.gov (United States)

    Henry, N

    1976-03-01

    The growth requirements of several yeasts isolated from San Francisco sour dough mother sponges were compared with those of bakers' yeast. The sour dough yeasts studied were one strain of Saccharomyces uvarum, one strain of S. inusitatus, and four strains of S. exiguus. S. inusitatus was the only yeast found to have an amino acid requirement, namely, methionine. All of the yeasts had an absolute requirement for pantothenic acid and a partial requirement for biotin. Inositol was stimulatory to all except bakers' yeast. All strains of S. exiguus required niacin and thiamine. Interestingly, S. inusitatus, the only yeast that required methionine, also needed folic acid. For optimal growth of S. exiguus in a molasses medium, supplementation with thiamine was required.

  10. Notes on a Mesodinium rubrum red tide in San Francisco Bay (California, USA)

    Science.gov (United States)

    Cloern, James E.; Cole, Brian E.; Hager, Stephen W.

    1994-01-01

    Discrete red patches of water were observed in South San Francisco Bay (USA) on 30 April 1993, and examination of live samples showed that this red tide was caused by surface accumulations of the pigmented ciliate Mesodinium rubrum . Vertical profiles showed strong salinity and temperature stratification in the upper 5 m, peak chlorophyll fluorescence in the upper meter, and differences in the small-scale density structure and fluorescence distribution among red patches. Events preceding this Mesodinium red tide included: (i) heavy precipitation and run-off, allowing for strong salinity stratification; (ii) a spring diatom bloom where the chlorophyll a concentration reached 50 mg m −3 ; (ii) depletions of dissolved inorganic N and Si in the photic zone; and (iv) several days of rapid warming and stabilization of the upper surface layer. These conditions may be general prerequisites for M.rubrum blooms in temperate estuaries.

  11. 1993 Annual Report: San Francisco estuary regional monitoring program for trace substances

    Science.gov (United States)

    Thompson, B.; Lacy, Jessica; Hardin, Dane; Grovhaug, Tom; Taberski, K.; Jassby, Alan D.; Cloern, James E.; Caffrey, J.; Cole, B.; Schoellhamer, David H.

    1993-01-01

    This first annual report of the San Francisco Estuary Regional Monitoring Program contains the results of monitoring measurements made in 1993. Measurements of conventional water quality parameters and trace contaminant concentrations were made at 16 stations throughout the Estuary three times during the year: the wet period (March), during declining Delta outflow (May), and during the dry period (September). Water toxicity tests were conducted at 8 of those stations. Measurements of sediment quality and contaminant concentrations were made at the same 16 stations during the wet and dry sampling periods. Sediment toxicity was measured at 8 of those stations. Transplanted, bagged bivalve bioaccumulation and condition was measured at 11 stations during the wet and dry sampling periods.

  12. Multiple Types of Childhood and Adult Violence Among Homeless and Unstably Housed Women in San Francisco.

    Science.gov (United States)

    Wong, Lauren H; Shumway, Martha; Flentje, Annesa; Riley, Elise D

    2016-12-01

    This study examined the relationship between different forms of childhood violence (emotional, physical, and sexual) and these same forms of violence in adulthood, using a crosssectional baseline survey of 298 homeless and unstably housed women in San Francisco, California. We also examined other related factors, including mental illnesses diagnosis, sex exchange, jail time, HIV status, and sociodemographic information. Regression analysis indicated that although several of these factors were associated with experiences of violence as an adult, specific types of child violence (e.g., sexual violence) predicted instances of that same type of violence as an adult but not necessarily other types. Thus, risk of adult violence among low-income women may be better predicted and addressed through histories of same-type childhood violence, despite years of intervening exposures and stressors.

  13. Linking hydrodynamic complexity to delta smelt (Hypomesus transpacificus) distribution in the San Francisco Estuary, USA

    Science.gov (United States)

    Bever, Aaron J.; MacWilliams, Michael L.; Herbold, Bruce; Brown, Larry R.; Feyrer, Frederick V.

    2016-01-01

    Long-term fish sampling data from the San Francisco Estuary were combined with detailed three dimensional hydrodynamic modeling to investigate the relationship between historical fish catch and hydrodynamic complexity. Delta Smelt catch data at 45 stations from the Fall Midwater Trawl (FMWT) survey in the vicinity of Suisun Bay were used to develop a quantitative catch-based station index. This index was used to rank stations based on historical Delta Smelt catch. The correlations between historical Delta Smelt catch and 35 quantitative metrics of environmental complexity were evaluated at each station. Eight metrics of environmental conditions were derived from FMWT data and 27 metrics were derived from model predictions at each FMWT station. To relate the station index to conceptual models of Delta Smelt habitat, the metrics were used to predict the station ranking based on the quantified environmental conditions. Salinity, current speed, and turbidity metrics were used to predict the relative ranking of each station for Delta Smelt catch. Including a measure of the current speed at each station improved predictions of the historical ranking for Delta Smelt catch relative to similar predictions made using only salinity and turbidity. Current speed was also found to be a better predictor of historical Delta Smelt catch than water depth. The quantitative approach developed using the FMWT data was validated using the Delta Smelt catch data from the San Francisco Bay Study. Complexity metrics in Suisun Bay were-evaluated during 2010 and 2011. This analysis indicated that a key to historical Delta Smelt catch is the overlap of low salinity, low maximum velocity, and low Secchi depth regions. This overlap occurred in Suisun Bay during 2011, and may have contributed to higher Delta Smelt abundance in 2011 than in 2010 when the favorable ranges of the metrics did not overlap in Suisun Bay.

  14. Religiosidad e identidad en San Francisco de Campeche. Siglos XVI y XVII

    Directory of Open Access Journals (Sweden)

    Rocher Salas, Adriana Delfina

    2006-12-01

    Full Text Available This study examines the problems concomitant to the development of a common identity among the Spanish settlers of San Francisco de Campeche during the Colonial period, with focus on the role played by religious elements in the shaping of this identity – in particular, the cult to the saints. An analysis of factors such as the characteristics of the saints in the neighborhood and local associations; processes of cult adoption, adaptation or dismissal; as well as the participation of the different local sectors in promoting the to their respective saints will be presented. This analysis will take into consideration the conflictive relationship between Spanish settlers and native people in Yucatán, a situation that prevented the using of aboriginal cultural elements in the shaping of a new identity

    Este trabajo estudia los problemas que acompañaron la gestación de una identidad propia y común para los residentes hispanos de la villa y puerto de San Francisco de Campeche durante el período colonial y la participación de elementos religiosos, particularmente el culto a los santos patronos, en el proceso. Teniendo como telón de fondo la peculiaridad de la región yucateca, donde una conflictiva relación entre españoles e indígenas impidió la utilización de elementos culturales prehispánicos en la formación de una conciencia identitaria, se analizan diversos factores, como las características de los santos tutelares de los barrios y de algunas corporaciones locales, los procesos de adopción, adaptación u olvido de sus cultos por parte del vecindario porteño y la participación de los diferentes sectores locales en la promoción de sus santos patronos.

  15. Geomorphometric analysis of the scoria cones of the San Francisco Volcanic Field using polar coordinate transformation

    Science.gov (United States)

    Vörös, Fanni; Koma, Zsófia; Karátson, Dávid; Székely, Balázs

    2016-04-01

    Scoria cones are often studied using geomorphometric and traditional GIS methods, e.g. aspect, slope histograms, area, cone height/width ratio. In order to enhance the non-symmetric shape components in contrast to the conical forms, we used a new approach in our research: the polar coordinate transformation (PCT) introduced by Székely & Karátson (2004). The study area is the classic cluster of scoria cones at the San Francisco Volcanic Field (SFVF) encompassing roughly 600 scoria cones as well as the San Francisco stratovolcano. Our goal is to analyse the even slight asymmetric shape of the scoria cones, and to generalize our findings. The area is a well-studied volcanic field, with a great number of available geological and geomorphological information, so comparing our PCT results with the data in literature is feasible. Polar coordinate transformation, being a one-to-one transformation, maps the original Cartesian coordinates (X, Y in meters) to radial distance (m) and azimuth (°) values. Our inputs were digitized polygons. We created images in the transformed coordinate system that clearly show the asymmetrical shape of the scoria cones. This asymmetry is found to be related to some extent to denudation, and to the age of the volcanic edifice that correlates with differential erosion. However, original asymmetries related to formation (e.g. rifting, emplacement on slope, eruption variations etc.) are also reasonable. The applied technique allows to define new derivatives of volcano-geomorphological parameters. The resultant scoria cone patterns have been manually categorized, however, the results are suitable for automated classification which is our next purpose. BSz contributed as an Alexander von Humboldt Research Fellow. Székely, B. & Karátson, D. (2004): DEM-based morphometry as a tool for reconstructing primary volcanic landforms: examples from the Börzsöny Mountains, Hungary, Geomorphology 63:25-37.

  16. What Determines Water Temperature Dynamics in the San Francisco Bay-Delta System?

    Science.gov (United States)

    Vroom, J.; van der Wegen, M.; Martyr-Koller, R. C.; Lucas, L. V.

    2017-11-01

    Water temperature is an important factor determining estuarine species habitat conditions. Water temperature is mainly governed by advection (e.g., from rivers) and atmospheric exchange processes varying strongly over time (day-night, seasonally) and the spatial domain. On a long time scale, climate change will impact water temperature in estuarine systems due to changes in river flow regimes, air temperature, and sea level rise. To determine which factors govern estuarine water temperature and its sensitivity to changes in its forcing, we developed a process-based numerical model (Delft3D Flexible Mesh) and applied it to a well-monitored estuarine system (the San Francisco Estuary) for validation. The process-based approach allows for detailed process description and a physics-based analysis of governing processes. The model was calibrated for water year 2011 and incorporated 3-D hydrodynamics, salinity intrusion, water temperature dynamics, and atmospheric coupling. Results show significant skill in reproducing temperature observations on daily, seasonal, and yearly time scales. In North San Francisco Bay, thermal stratification is present, enhanced by salinity stratification. The temperature of the upstream, fresh water Delta area is captured well in 2-D mode, although locally—on a small scale—vertical processes (e.g., stratification) may be important. The impact of upstream river temperature and discharge and atmospheric forcing on water temperatures differs throughout the Delta, possibly depending on dispersion and residence times. Our modeling effort provides a sound basis for future modeling studies including climate change impact on water temperature and associated ecological modeling, e.g., clam and fish habitat and phytoplankton dynamics.

  17. Spatial variability of suspended sediment concentration within a tidal marsh in San Francisco Estuary

    Science.gov (United States)

    Swanson, K.; Drexler, J. Z.; Schoellhamer, D. H.; Buffington, K.; Takekawa, J.

    2012-12-01

    The sustainability of existing marshes and feasibility of future marsh restoration projects in San Francisco Estuary and elsewhere are threatened by a potential imbalance between accelerating sea-level rise and tidal marsh accretion rates. Marsh accretion is, in large part, dependent upon the availability of suspended sediment supplied from adjacent waterways. As water and sediment move across a marsh plain, suspended sediment settles and is trapped by vegetation near the source, resulting in less suspended-sediment concentration (SSC) and deposition in the interior of the marsh. Measurements of deposition and limited observations of SSC within marshes have confirmed a decrease in sediment supply and accumulation from the marsh edge to the marsh interiors, but the spatial variability of SSC has not been quantified in a manner that allows for comparison to a theoretical sediment transport model. For this study, transects of SSC were collected within a marsh at China Camp State Park in the San Francisco Estuary which demonstrate that a dominant pattern of settling can be quantified and generally matches the exponentially decreasing pattern of SSC predicted by a simple advection-settling model. The observed pattern suggests that sediment settling and marsh flow characteristics are consistent both spatially (between transects) and temporally (between monthly sampling events). However, deviations from the predicted pattern occurred systematically at some locations and are likely related to resuspension of sediment from the marsh surface or small, unmapped creek channels that supply sediment to the marsh. Despite these deviations, our data show this simple 1-D model of advection and settling can be used to generalize within-marsh sediment transport as a function of distance from the nearest sediment source.

  18. State of transition: Marijuana use among young adults in the San Francisco Bay Area.

    Science.gov (United States)

    Holmes, Louisa M; Popova, Lucy; Ling, Pamela M

    2016-09-01

    California may vote on marijuana legalization in 2016. Young adults have the highest rates of marijuana use, but little is known about the correlates of use in this age group, including factors that may be affected by policy change. We investigated whether there are differences in marijuana use by sociodemographic characteristics, psychological distress, loneliness and social support, controlling for risk factors such as alcohol and cigarette use as well as perceived harm of marijuana. Bivariate and multivariable analysis of past 30day marijuana use using the 2014 San Francisco Bay Area Young Adult Health Survey, a probabilistic multi-mode survey of (N=1324) young adults (aged 18-26years) residing in Alameda and San Francisco Counties, stratified by race/ethnicity. 291 (27%) sample participants reported current marijuana use. Compared to non-Hispanic Whites (referent) Asian/Pacific Islander respondents were less likely to use marijuana (AOR, 0.42; 95% CI, 0.22-0.80) while multiracial participants were twice as likely (AOR, 2.27; 95% CI, 1.06-4.85). Psychological distress was not related to marijuana use, but social support (AOR, 1.42; 95% CI, 1.08-1.88) and loneliness (AOR, 1.42; 95% CI, 1.09-1.86) were. Perceived harm of marijuana was inversely related to marijuana use (AOR, 0.60; 95% CI, 0.51-0.70), while smoking cigarettes (AOR, 3.95; 95% CI, 2.28-6.84) and binge drinking (AOR, 1.13; 95% CI, 1.03-1.24) were positively related. Legalization policies should include public education campaigns addressing potential harms of marijuana use particularly targeting multiracial young adults who also engage in other risk behaviors, such as cigarette smoking and binge drinking. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Real-time earthquake alert system for the greater San Francisco Bay Area: a prototype design to address operational issues

    Energy Technology Data Exchange (ETDEWEB)

    Harben, P.E.; Jarpe, S.; Hunter, S.

    1996-12-10

    The purpose of the earthquake alert system (EAS) is to outrun the seismic energy released in a large earthquake using a geographically distributed network of strong motion sensors that telemeter data to a rapid CPU-processing station, which then issues an area-wide warning to a region before strong motion will occur. The warning times involved are short, from 0 to 30 seconds or so; consequently, most responses must be automated. The San Francisco Bay Area is particularly well suited for an EAS because (1) large earthquakes have relatively shallow hypocenters (10- to 20-kilometer depth), giving favorable ray-path geometries for larger warning times than deeper from earthquakes, and (2) the active faults are few in number and well characterized, which means far fewer geographically distributed strong motion sensors are (about 50 in this region). An EAS prototype is being implemented in the San Francisco Bay Area. The system consists of four distinct subsystems: (1) a distributed strong motion seismic network, (2) a central processing station, (3) a warning communications system and (4) user receiver and response systems. We have designed a simple, reliable, and inexpensive strong motion monitoring station that consists of a three-component Analog Devices ADXLO5 accelerometer sensing unit, a vertical component weak motion sensor for system testing, a 16-bit digitizer with multiplexing, and communication output ports for RS232 modem or radio telemetry. The unit is battery-powered and will be sited in fire stations. The prototype central computer analysis system consists of a PC dam-acquisition platform that pipes the incoming strong motion data via Ethernet to Unix-based workstations for dam processing. Simple real-time algorithms, particularly for magnitude estimation, are implemented to give estimates of the time since the earthquake`s onset its hypocenter location, its magnitude, and the reliability of the estimate. These parameters are calculated and transmitted

  20. The role of tidal marsh restoration in fish management in the San Francisco Estuary

    Science.gov (United States)

    Herbold, Bruce; Baltz, Donald; Brown, Larry R.; Grossinger, Robin; Kimmerer, Wim J.; Lehman, Peggy W.; Moyle, Peter B.; Nobriga, Matthew L.; Simenstad, Charles A.

    2015-01-01

    Tidal marsh restoration is an important management issue in the San Francisco Estuary (estuary). Restoration of large areas of tidal marsh is ongoing or planned in the lower estuary (up to 6,000 ha, Callaway et al. 2011). Large areas are proposed for restoration in the upper estuary under the Endangered Species Act biological opinions (3,237 ha) and the Bay Delta Conservation Plan (26,305 ha). In the lower estuary, tidal marsh has proven its value to a wide array of species that live within it (Palaima 2012). In the Sacramento–San Joaquin Delta (Delta), one important function ascribed to restoration of freshwater tidal marshes is that they make large contributions to the food web of fish in open waters (BDCP 2013). The Ecosystem Restoration Program ascribed a suite of ecological functions to tidal marsh restoration, including habitat and food web benefits to native fish (CDFW 2010). This background was the basis for a symposium, Tidal Marshes and Native Fishes in the Delta: Will Restoration Make a Difference? held at the University of California, Davis, on June 10, 2013. This paper summarizes conclusions the authors drew from the symposium.

  1. Shifting shoals and shattered rocks : How man has transformed the floor of west-central San Francisco Bay

    Science.gov (United States)

    Chin, John L.; Wong, Florence L.; Carlson, Paul R.

    2004-01-01

    San Francisco Bay, one of the world's finest natural harbors and a major center for maritime trade, is referred to as the 'Gateway to the Pacific Rim.' The bay is an urbanized estuary that is considered by many to be the major estuary in the United States most modified by man's activities. The population around the estuary has grown rapidly since the 1850's and now exceeds 7 million people. The San Francisco Bay area's economy ranks as one of the largest in the world, larger even than that of many countries. More than 10 million tourists are estimated to visit the bay region each year. The bay area's population and associated development have increasingly changed the estuary and its environment. San Francisco Bay and the contiguous Sacramento-San Joaquin Delta encompass roughly 1,600 square miles (4,100 km2) and are the outlet of a major watershed that drains more than 40 percent of the land area of the State of California. This watershed provides drinking water for 20 million people (two thirds of the State's population) and irrigates 4.5 million acres of farmland and ranchland. During the past several decades, much has been done to clean up the environment and waters of San Francisco Bay. Conservationist groups have even bought many areas on the margins of the bay with the intention of restoring them to a condition more like the natural marshes they once were. However, many of the major manmade changes to the bay's environment occurred so long ago that the nature of them has been forgotten. In addition, many changes continue to occur today, such as the introduction of exotic species and the loss of commercial and sport fisheries because of declining fish populations. The economy and population of the nine counties that surround the bay continue to grow and put increasing pressure on the bay, both direct and indirect. Therefore, there are mixed signals for the future health and welfare of San Francisco Bay. The San Francisco Bay estuary consists of three

  2. Empirical evidence for synchrony in the evolution of TB cases and HIV+ contacts among the San Francisco homeless.

    Directory of Open Access Journals (Sweden)

    Mojdeh Mohtashemi

    Full Text Available The re-emergence of tuberculosis (TB in the mid-1980s in many parts of the world, including the United States, is often attributed to the emergence and rapid spread of human immunodeficiency virus (HIV and acquired immunodeficiency syndrome (AIDS. Although it is well established that TB transmission is particularly amplified in populations with high HIV prevalence, the epidemiology of interaction between TB and HIV is not well understood. This is partly due to the scarcity of HIV-related data, a consequence of the voluntary nature of HIV status reporting and testing, and partly due to current practices of screening high risk populations through separate surveillance programs for HIV and TB. The San Francisco Department of Public Health, TB Control Program, has been conducting active surveillance among the San Francisco high-risk populations since the early 1990s. We present extensive TB surveillance data on HIV and TB infection among the San Francisco homeless to investigate the association between the TB cases and their HIV+ contacts. We applied wavelet coherence and phase analyses to the TB surveillance data from January 1993 through December 2005, to establish and quantify statistical association and synchrony in the highly non-stationary and ostensibly non-periodic waves of TB cases and their HIV+ contacts in San Francisco. When stratified by homelessness, we found that the evolution of TB cases and their HIV+ contacts is highly coherent over time and locked in phase at a specific periodic scale among the San Francisco homeless, but no significant association was observed for the non-homeless. This study confirms the hypothesis that the dynamics of HIV and TB are significantly intertwined and that HIV is likely a key factor in the sustenance of TB transmission among the San Francisco homeless. The findings of this study underscore the importance of contact tracing in detection of HIV+ individuals that may otherwise remain undetected, and

  3. Wed. May 13, Hayward, Calif. -- EPA Administrator McCarthy joins San Francisco Bay Area agencies to celebrate nations largest solar energy partnership

    Science.gov (United States)

    SAN FRANCISCO - On Wednesday, May 13, U.S. EPA Administrator Gina McCarthy will join Bay Area agencies to celebrate the nation's largest local government collaborative for solar power and launch the nation's first federal solar partnership. Administ

  4. EX1006 Hawaii to San Francisco Transit to Drydock (EX1006, EM302) on Okeanos Explorer in Hawaii, US West Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Okeanos Explorer (EX) will transit from Honolulu, HI to San Francisco for the winter inport and drydock period. During the transit, the EX will perform 24-hour...

  5. Amendment to refuge hunting plan for waterfowl on 5,500 acres of former commercial salt ponds : Don Edwards San Francisco Bay NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This amendment to the 1982 Don Edwards San Francisco Bay NWR waterfowl hunting plan was written to address 5,500 acres of salt pond recently acquisitioned by the...

  6. Developing a spatially-explicit climate adaptation framework for estuarine ecosystems of the San Francisco Bay: Climate Adaptation for Decision Support (CADS Phase 1)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides recommended resource allocations for conserving four subregions of San Francisco (SF) Bay, including North Bay, Suisun, Central Bay and South...

  7. Establishing baseline conditions to inform adaptive management of South San Francisco Bay salt ponds: A comparison of waterbird abundance from the 1980s to the 2000s

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The 30,000 acres of wetlands within the Don Edwards San Francisco Bay National Wildlife Refuge (Refuge) provide critical habitat for over one million waterbirds...

  8. A Tale of Two Cities: Access to Care and Services Among African-American Transgender Women in Oakland and San Francisco

    OpenAIRE

    Nemoto, Tooru; Cruz, Taylor M.; Iwamoto, Mariko; Sakata, Maria

    2015-01-01

    Purpose: The San Francisco Bay Area attracts people from all over the country due to the perception of lesbian, gay, bisexual, and transgender (LGBT) acceptance and affirmation. African-American transgender women are severely marginalized across society and as such have many unmet health and social service needs. This study sought to quantitatively assess unmet needs among African-American transgender women with a history of sex work by comparing residents of Oakland versus San Francisco.

  9. The Performance of Nearshore Dredge Disposal at Ocean Beach, San Francisco, California, 2005-2007

    Science.gov (United States)

    Barnard, Patrick L.; Erikson, Li H.; Hansen, Jeff E.; Elias, Edwin

    2009-01-01

    Ocean Beach, California, contains an erosion hot spot in the shadow of the San Francisco ebb tidal delta that threatens valuable public infrastructure as well as the safe recreational use of the beach. In an effort to reduce the erosion at this location a new plan for the management of sediment dredged annually from the main shipping channel at the mouth of San Francisco Bay was implemented in May 2005 by the United States Army Corps of Engineers, San Francisco District (USACE). The USACE designated a temporary nearshore dredge disposal site for the annual disposal of about 230,000 m3 (300,000 yd3) of sand about 750 m offshore and slightly south of the erosion hot spot, in depths between approximately 9 and 14 m. The site has now been used three times for a total sediment disposal of about 690,000 m3 (about 900,000 yds3). The disposal site was chosen because it is in a location where strong tidal currents and open-ocean waves can potentially feed sediment toward the littoral zone in the reach of the beach that is experiencing critical erosion, as well as prevent further scour on an exposed outfall pipe. The onshore migration of sediment from the target disposal location might feed the primary longshore bar or the nearshore zone, and provide a buffer to erosion that peaks during winter months when large waves impact the region. The United States Geological Survey (USGS) has been monitoring and modeling the bathymetric evolution of the test dredge disposal site and the adjacent coastal region since inception in May 2005. This paper reports on the first 2.5 years of this monitoring program effort (May 2005 to December 2007) and assesses the short-term coastal response. Here are the key findings of this report: *Approximately half of the sediment that has been placed in the nearshore dredge-disposal site during the 2.5 years of this study remains within the dredge focus area. *In the winter of 2006-7, large waves transported the dredge-mound material onshore. *High

  10. Confirmatory sediment analyses and solid and suspended particulate phase bioassays on sediment from Oakland Inner Harbor, San Francisco, California

    Energy Technology Data Exchange (ETDEWEB)

    Word, J.Q.; Ward, J.A.; Apts, C.W.; Woodruff, D.L.; Barrows, M.E.; Cullinan, V.I.; Hyland, J.L.; Campbell, J.F.

    1988-12-01

    The US Army Corps of Engineers (USACE), San Francisco District, was authorized by the US Congress to deepen the navigation channels of Inner and Outer Oakland Harbor, California. During review of the environmental impact statement required for this dredging and disposal project, a panel of national experts approved the open-water disposal of dredged sediment from selected areas within the Inner Harbor, subject to results of confirmatory solid phase bioassays. The San Francisco District of the Corps requested the Battle/Marine Sciences Laboratory (MSL) to conduct these confirmatory studies. The studies provided technical data for an evaluation of the potential environmental impact of this project. Within extremely narrow time constraints, these studies provided chemical and biological information required by ocean dumping regulations to determine suitability of the Oakland Inner Harbor and turning basin sediment for ocean disposal. 23 refs., 18 figs., 45 tabs.

  11. Mercury in birds of San Francisco Bay-Delta, California: trophic pathways, bioaccumulation, and ecotoxicological risk to avian reproduction

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.; Heinz, Gary; De La Cruz, Susan E. W.; Takekawa, John Y.; Miles, A. Keith; Adelsbach, Terrence L.; Herzog, Mark P.; Bluso-Demers, Jill D.; Demers, Scott A.; Herring, Garth; Hoffman, David J.; Hartman, Christopher A.; Willacker, James J.; Suchanek, Thomas H.; Schwarzbach, Steven E.; Maurer, Thomas C.

    2014-01-01

    San Francisco Bay Estuary in northern California has a legacy of mercury contamination, which could reduce the health and reproductive success of waterbirds in the estuary. The goal of this study was to use an integrated field and laboratory approach to evaluate the risks of mercury exposure to birds in the estuary. We examined mercury bioaccumulation, and other contaminants of concern, in five waterbird species that depend heavily on San Francisco Bay Estuary for foraging and breeding habitat: American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), Forster’s terns (Sterna forsteri), Caspian terns (Hydroprogne caspia), and surf scoters (Melanitta perspicillata). These species have different foraging habitats and diets that represent three distinct foraging guilds within the estuary’s food web. In this report, we provide an integrated synthesis of the primary findings from this study and results are synthesized from 54 peer-reviewed publications generated to date with other unpublished results.

  12. Promoting Health and Safety in San Francisco's Chinatown Restaurants: Findings and Lessons Learned from a Pilot Observational Checklist

    Science.gov (United States)

    Gaydos, Megan; Bhatia, Rajiv; Morales, Alvaro; Lee, Pam Tau; Liu, Shaw San; Chang, Charlotte; Salvatore, Alicia L.; Krause, Niklas; Minkler, Meredith

    2011-01-01

    Noncompliance with labor and occupational health and safety laws contributes to economic and health inequities. Environmental health agencies are well positioned to monitor workplace conditions in many industries and support enhanced enforcement by responsible regulatory agencies. In collaboration with university and community partners, the San Francisco Department of Public Health used an observational checklist to assess preventable occupational injury hazards and compliance with employee notification requirements in 106 restaurants in San Francisco's Chinatown. Sixty-five percent of restaurants had not posted required minimum wage, paid sick leave, or workers' compensation notifications; 82% of restaurants lacked fully stocked first-aid kits; 52% lacked antislip mats; 37% lacked adequate ventilation; and 28% lacked adequate lighting. Supported by a larger community-based participatory research process, this pilot project helped to spur additional innovative health department collaborations to promote healthier workplaces. PMID:21836739

  13. Sub-tidal benthic habitats of central San Francisco Bay and offshore Golden Gate area: A review

    Science.gov (United States)

    Greene, H. Gary; Endris, Charles; Vallier, Tracy; Golden, Nadine E.; Cross, Jeffery; Ryan, Holly F.; Dieter, Bryan; Niven, Eric; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    Deep-water potential estuarine and marine benthic habitat types were defined from a variety of new and interpreted data sets in central San Francisco Bay and offshore Golden Gate area including multibeam echosounder (MBES), side-scan sonar and bottom grab samples. Potential estuarine benthic habitats identified for the first time range from hard bedrock outcrops on island and mainland flanks and some Bay floor

  14. Gold rush entrepôt: The maritime archaeology of the rise of the Port of San Francisco

    OpenAIRE

    Delgado, James Preston

    2006-01-01

    The California Gold Rush of 1848-1 852 transformed San Francisco into a major city. This rapid rise, often attributed by historians to the accident of the gold discovery, is more a result of centuries-long processes of integration of the Pacific into the European world system. Integration of the Pacific occurred through maritime exploration, trade and commerce. By the mid-nineteenth century, California and its gold was another commodity in the longue duree of Pacific integration. Ships respon...

  15. Redundancy in Public Transit - Vol III. The Political Economy of Transit in the San Francisco Bay Area, 1945-63

    OpenAIRE

    Seymour Adler

    1980-01-01

    This report focuses on two concrete developments. One is the historical process that produced the Bay Area Rapid Transit District in 1957 and the district's particular regional rapid transit plan, approved by the voters of Alameda, Contra Costa, and San Francisco counties in November, 1962. The other is the process that produced the Alameda-Contra Costa Transit District in 1955 and 1956, and the particular transit service this District began operating in 1960. The relation between the two dis...

  16. Achieving Health Equity Through Community Engagement in Translating Evidence to Policy: The San Francisco Health Improvement Partnership, 2010–2016

    Science.gov (United States)

    Vargas, Roberto A.; Fleisher, Paula; Aragón, Tomás J.; Chung, Lisa; Chawla, Colleen; Yant, Abbie; Garcia, Estela R.; Santiago, Amor; Lang, Perry L.; Jones, Paula; Liu, Wylie; Schmidt, Laura A.

    2017-01-01

    Background The San Francisco Health Improvement Partnership (SFHIP) promotes health equity by using a novel collective impact model that blends community engagement with evidence-to-policy translational science. The model involves diverse stakeholders, including ethnic-based community health equity coalitions, the local public health department, hospitals and health systems, a health sciences university, a school district, the faith community, and others sectors. Community Context We report on 3 SFHIP prevention initiatives: reducing consumption of sugar sweetened beverages (SSBs), regulating retail alcohol sales, and eliminating disparities in children’s oral health. Methods SFHIP is governed by a steering committee. Partnership working groups for each initiative collaborate to 1) develop and implement action plans emphasizing feasible, scalable, translational-science–informed interventions and 2) consider sustainability early in the planning process by including policy and structural interventions. Outcome Through SFHIP’s efforts, San Francisco enacted ordinances regulating sale and advertising of SSBs and a ballot measure establishing a soda tax. Most San Francisco hospitals implemented or committed to implementing healthy-beverage policies that prohibited serving or selling SSBs. SFHIP helped prevent Starbucks and Taco Bell from receiving alcohol licenses in San Francisco and helped prevent state authorization of sale of powdered alcohol. SFHIP increased the number of primary care clinics providing fluoride varnish at routine well-child visits from 3 to 14 and acquired a state waiver to allow dental clinics to be paid for dental services delivered in schools. Interpretation The SFHIP model of collective impact emphasizing community engagement and policy change accomplished many of its intermediate goals to create an environment promoting health and health equity. PMID:28333598

  17. Achieving Health Equity Through Community Engagement in Translating Evidence to Policy: The San Francisco Health Improvement Partnership, 2010-2016.

    Science.gov (United States)

    Grumbach, Kevin; Vargas, Roberto A; Fleisher, Paula; Aragón, Tomás J; Chung, Lisa; Chawla, Colleen; Yant, Abbie; Garcia, Estela R; Santiago, Amor; Lang, Perry L; Jones, Paula; Liu, Wylie; Schmidt, Laura A

    2017-03-23

    The San Francisco Health Improvement Partnership (SFHIP) promotes health equity by using a novel collective impact model that blends community engagement with evidence-to-policy translational science. The model involves diverse stakeholders, including ethnic-based community health equity coalitions, the local public health department, hospitals and health systems, a health sciences university, a school district, the faith community, and others sectors. We report on 3 SFHIP prevention initiatives: reducing consumption of sugar sweetened beverages (SSBs), regulating retail alcohol sales, and eliminating disparities in children's oral health. SFHIP is governed by a steering committee. Partnership working groups for each initiative collaborate to 1) develop and implement action plans emphasizing feasible, scalable, translational-science-informed interventions and 2) consider sustainability early in the planning process by including policy and structural interventions. Through SFHIP's efforts, San Francisco enacted ordinances regulating sale and advertising of SSBs and a ballot measure establishing a soda tax. Most San Francisco hospitals implemented or committed to implementing healthy-beverage policies that prohibited serving or selling SSBs. SFHIP helped prevent Starbucks and Taco Bell from receiving alcohol licenses in San Francisco and helped prevent state authorization of sale of powdered alcohol. SFHIP increased the number of primary care clinics providing fluoride varnish at routine well-child visits from 3 to 14 and acquired a state waiver to allow dental clinics to be paid for dental services delivered in schools. The SFHIP model of collective impact emphasizing community engagement and policy change accomplished many of its intermediate goals to create an environment promoting health and health equity.

  18. Review of wastewater problems and wastewater-management planning in the San Francisco Bay region, California

    Science.gov (United States)

    Hines, Walter G.

    1973-01-01

    The San Francisco Bay region has suffered adverse environmental effects related to the discharge of municipal-, industrial-, and agricultural- wastewater and storm-water runoff. Specific pollutional properties of theses discharges are not well understood in all cases although the toxic materials and aquatic-plant nutrients (biostimulants) found in municipal and industrial waterwater are considered to be a major cause of regional water-quality problems. Other water-quality problems in the region are commonly attributed to pesticides found in agricultural wastewater and potentially pathogenic bacteria in municipal-wastewater discharges and in storm-water runoff. The geographical distribution and magnitude of wastewater discharges in the bay region, particularly those from municipalities and industries, is largely a function of population, economic growth, and urban development. As might be expected, the total volume of wastewater has increased in a trend paralleling this growth and development. More significant, perhaps, is the fact that the total volume parameters such as BOD (biochemical oxygen demand), biostimulant concentrations, and toxicity, has increased despite large expenditures on new and improved municipal- and industrial-wastewater-treatment plants. Also, pollutant loadings from other major source, such as agriculture and storm-water runoff, have increased. At the time of writing (1972), many Federal, State, regional, and local agencies are engaged in a comprehensive wastewater-management-planning effort for the entire bay region. Initial objectives of this planning effort are: (1) the consolidation and coordination of loosely integrated wastewater-management facilities and (2) the elimination of wastewater discharges to ecologically sensitive areas, such as fresh-water streams and shallow extremities of San Francisco Bay. There has been some investigation of potential long-range wastewater-management alternatives based upon disposal in deep water in the

  19. Impacts of the 2014 severe drought on the Microcystis bloom in San Francisco Estuary.

    Science.gov (United States)

    Lehman, P W; Kurobe, T; Lesmeister, S; Baxa, D; Tung, A; Teh, S J

    2017-03-01

    The increased frequency and intensity of drought with climate change may cause an increase in the magnitude and toxicity of freshwater cyanobacteria harmful algal blooms (CHABs), including Microcystis blooms, in San Francisco Estuary, California. As the fourth driest year on record in San Francisco Estuary, the 2014 drought provided an opportunity to directly test the impact of severe drought on cyanobacteria blooms in SFE. A field sampling program was conducted between July and December 2014 to sample a suite of physical, chemical, and biological variables at 10 stations in the freshwater and brackish reaches of the estuary. The 2014 Microcystis bloom had the highest biomass and toxin concentration, earliest initiation, and the longest duration, since the blooms began in 1999. Median chlorophyll a concentration increased by 9 and 12 times over previous dry and wet years, respectively. Total microcystin concentration also exceeded that in previous dry and wet years by a factor of 11 and 65, respectively. Cell abundance determined by quantitative PCR indicated the bloom contained multiple potentially toxic cyanobacteria species, toxic Microcystis and relatively high total cyanobacteria abundance. The bloom was associated with extreme nutrient concentrations, including a 20-year high in soluble reactive phosphorus concentration and low to below detection levels of ammonium. Stable isotope analysis suggested the bloom varied with both inorganic and organic nutrient concentration, and used ammonium as the primary nitrogen source. Water temperature was a primary controlling factor for the bloom and was positively correlated with the increase in both total and toxic Microcystis abundance. In addition, the early initiation and persistence of warm water temperature coincided with the increased intensity and duration of the Microcystis bloom from the usual 3 to 4 months to 8 months. Long residence time was also a primary factor controlling the magnitude and persistence of

  20. Drivers of change in estuarine-coastal ecosystems: Discoveries from four decades of study in San Francisco Bay

    Science.gov (United States)

    Cloern, J.E.; Jassby, A.D.

    2012-01-01

    Poised at the interface of rivers, ocean, atmosphere and dense human settlement, estuaries are driven by a large array of natural and anthropogenic forces. San Francisco Bay exemplifies the fast-paced change occurring in many of the world's estuaries, bays and inland seas in response to these diverse forces. We use observations from this particularly well-studied estuary to illustrate responses to six drivers that are common agents of change where land and sea meet: water consumption and diversion; human modification of sediment supply; introduction of non-native species; sewage input; environmental policy; and climate shifts. In San Francisco Bay, responses to these drivers include, respectively, shifts in the timing and extent of freshwater inflow and salinity intrusion; decreasing turbidity; restructuring of plankton communities; nutrient enrichment; elimination of hypoxia and reduced metal contamination of biota; and food web changes that decrease resistance of the estuary to nutrient pollution. Detection of these changes and discovery of their causes through environmental monitoring have been essential for establishing and measuring outcomes of environmental policies that aim to maintain high water quality and sustain services provided by estuarine-coastal ecosystems. The wide range of variability time scales and the multiplicity of interacting drivers place heavy demands on estuarine monitoring programs. But the San Francisco Bay case study illustrates why the imperative for monitoring has never been greater.

  1. Data from theodolite measurements of creep rates on San Francisco Bay region faults, California: 1979-2001

    Science.gov (United States)

    Galehouse, Jon S.

    2002-01-01

    My purpose is to make our creep data on San Francisco Bay region active faults available to the scientific research community. My student research assistants and I measured creep (aseismic slip) rates on these faults from 1979 until my retirement from the project in 2001. These data are further described in my final technical report as principal investigator, which summarizes results from 22 September 1979 through 28 February 2001 (Galehouse, 2001). We made over 2,600 creep measurements, about one-third in the ten years prior to the Loma Prieta earthquake (LPEQ) and two-thirds in the 11.4 years following it. The measurements are continuing to be made by members of the Geosciences Department at San Francisco State University (SFSU) under the direction of Karen Grove and John Caskey. A complete analysis of our results obtained on the Hayward fault is presented in Lienkaemper, Galehouse, and Simpson (2001). A formal report based on the entire San Francisco Bay region data set is in preparation. Data sheets for each site along the fault are available for downloading in Excel format to facilitate analysis of the data. They are also available as tab-delimited raw data. The data include all regular measurement sites, SF–1 through SF–34, and the 20 SFSU and U.S. Geological Survey (USGS) afterslip sites on the Hayward fault.

  2. Primary ciliary dyskinesia: a report from ATS 2001, May 18–23, San Francisco

    Directory of Open Access Journals (Sweden)

    Noone Peadar G

    2001-06-01

    Full Text Available Abstract Primary ciliary dyskinesia (PCD is a genetic disorder of abnormal ciliary structure and function that leads to defective mucociliary clearance, resulting in oto-sino-pulmonary disease, and infertility. The disease is currently under intense investigation by a number of research groups worldwide. At the recent American Thoracic Society meeting in San Francisco in May 2001, two sessions focused on PCD; a symposium session on May 21 with several featured expert speakers was followed by a mini-symposium on Tuesday May 22, with one featured speaker and presentation of nine abstracts covering a range of research topics. Mattias Salathe (University of Miami, USA and Stephen Brody (Washington University, St Louis, USA chaired the symposium session. Presentations focused on the clinical spectrum of PCD, the genetics of PCD, a proteomics approach to detail the structure of cilia, the role of cilia in the embryology of situs laterality, and airway epithelial cell biology. The mini-symposium was chaired by Peadar Noone (University of North Carolina, USA and Malcolm King (University of Alberta, USA and included presentations on the use of PCD as a human disease model, accurate definition of the phenotype using clinical and cell biologic markers, and molecular studies. The latter reports ranged from isolation of a protein involved in ciliary structure and function to genetic studies using linkage analysis and the candidate gene approach. Clinicians and scientists alike displayed considerable interest at both sessions, and there were several lively question–answer sessions.

  3. San Ignacio (La Tembladera) geothermal site, Departamento de Francisco Morazan, Honduras, Central America: Geological field report

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, M.J.; Eppler, D.; Heiken, G.; Flores, W.; Ramos, N.; Ritchie, A.

    1987-06-01

    The San Ignacio (La Tembladera) geothermal site is located on the north side of the Siria Valley, Departamento de Francisco Morazan, near the village of Barrosa. Hot springs are located along a northwest-trending fault scarp at the edge of the valley and along north-trending faults that cross the scarp. The rocks in the area are primarily Paleozoic metamorphic rocks, overlain by patches of Tertiary Padre Miguel Group tuffs and alluvial deposits. Movement probably occurred along several faults during latest Tertiary and possibly early Quaternary times. Four spring areas were mapped. Area 1, the largest, is associated with a sinter mound and consists of 40 spring groups. About half of the springs, aligned along a north-south trend, are boiling. Area 2 is a small sinter mound with several seeps. Area 3 consists of a group of hot and boiling springs aligned along a north-trending fault. The springs rise through fractured schists and a thin cover of alluvium. Area 4 is located at the intersection of several faults and includes one of the largest boiling springs in the area.

  4. Chinese Herb Use by Patients at a San Francisco Chinatown Public Health Center.

    Science.gov (United States)

    Hsu, Oliver; Tsourounis, Candy; Chan, Lenny Lok Shun; Dennehy, Cathi

    2016-09-01

    Chinese herbal medicine (CHM) use has not been well characterized in persons living in the United States who receive care by Western-trained healthcare providers. The primary objective of this study was to characterize use of CHM taken in the last 12 months by patients seen at a Chinatown public health center. Convenience sample survey. Data collection occurred over 3 months at a San Francisco Chinatown public health center. Adult patients visiting their primary care provider. Completion of a voluntary 24-question survey on CHM use. Prevalence, type, and indications for use. Survey response rate was 29% (50/170). Seventy percent (35/50) of respondents had used CHM in the last 12 months and 94% (33/35) were also taking prescription medicines. The three most commonly used CHM were goji berry (37%), Dioscorea (31%), and ginseng (23%). The most common indications for herbs used in the last 12 months were general wellness (34%), cold/flu (25%), and headache (6%). Sixty-four percent of respondents had used Western medicine in combination with CHM within the last 12 months. Sixty-nine percent of respondents who used CHM did not tell their Western provider about this use. No patient had CHM use documented in the electronic medical record. Patients seen at a Chinatown public health center frequently used CHM products in conjunction with Western prescription medicines. Providers should routinely enquire about CHM use for health as a soup, tea, food, or pill and document this use in the medical record.

  5. Changes in causes of death among persons with AIDS: San Francisco, California, 1996-2011.

    Science.gov (United States)

    Schwarcz, Sandra K; Vu, Annie; Hsu, Ling Chin; Hessol, Nancy A

    2014-10-01

    The increased life expectancy among HIV-infected persons treated with combination antiretroviral therapy (ART), risk behaviors, and co-morbidities associated with ART place HIV-infected persons at risk for non-HIV-related causes of death. We used the San Francisco HIV/AIDS registry to identify deaths that occurred from January 1996 through December 2011. Temporal trends in AIDS- and non-AIDS-related mortality rates, the proportion of underlying and contributory causes of death, and the ratio of observed deaths in the study population to expected number of deaths among California men aged 20-79 (standardized mortality ratio [SMR]) of underlying causes of death were examined. A total of 5338 deaths were identified. The annual AIDS-related death rate (per 100 deaths) declined from 10.8 in 1996 to 0.9 in 2011 (pdeath rate from non-AIDS-related causes declined from 2.1 in 1996 to 0.9 in 2011 (pdeaths due to all types of heart disease combined, all non-AIDS cancers combined, mental disorders resulting from substance abuse, drug overdose, suicide and chronic obstructive pulmonary disease increased significantly over time. The SMRs for liver diseased decreased significantly over time but remained elevated. Our data highlight the importance of age-related causes of death as well as deaths from causes that are, at least in part, preventable.

  6. Acoustic doppler velocimeter backscatter for quantification of suspended sediment concentration in South San Francisco Bay

    Science.gov (United States)

    Ozturk, Mehmet; Work, Paul

    2016-01-01

    A data set was acquired on a shallow mudflat in south San Francisco Bay that featured simultaneous, co-located optical and acoustic sensors for subsequent estimation of suspended sediment concentrations (SSC). The optical turbidity sensor output was converted to SSC via an empirical relation derived at a nearby site using bottle sample estimates of SSC. The acoustic data was obtained using an acoustic Doppler velocimeter. Backscatter and noise were combined to develop another empirical relation between the optical estimates of SSC and the relative backscatter from the acoustic velocimeter. The optical and acoustic approaches both reproduced similar general trends in the data and have merit. Some seasonal variation in the dataset was evident, with the two methods differing by greater or lesser amounts depending on which portion of the record was examined. It is hypothesized that this is the result of flocculation, affecting the two signals by different degrees, and that the significance or mechanism of the flocculation has some seasonal variability. In the earlier portion of the record (March), there is a clear difference that appears in the acoustic approach between ebb and flood periods, and this is not evident later in the record (May). The acoustic method has promise but it appears that characteristics of flocs that form and break apart may need to be accounted for to improve the power of the method. This may also be true of the optical method: both methods involve assuming that the sediment characteristics (size, size distribution, and shape) are constant

  7. Acoustic Doppler velocimeter backscatter for quantification of suspended sediment concentration in South San Francisco Bay, USA

    Science.gov (United States)

    Öztürk, Mehmet; Work, Paul

    2016-01-01

    A data set was acquired on a shallow mudflat in south San Francisco Bay that featured simultaneous, co-located optical and acoustic sensors for subsequent estimation of suspended sediment concentrations (SSC). The optical turbidity sensor output was converted to SSC via an empirical relation derived at a nearby site using bottle sample estimates of SSC. The acoustic data was obtained using an acoustic Doppler velocimeter. Backscatter and noise were combined to develop another empirical relation between the optical estimates of SSC and the relative backscatter from the acoustic velocimeter. The optical and acoustic approaches both reproduced similar general trends in the data and have merit. Some seasonal variation in the dataset was evident, with the two methods differing by greater or lesser amounts depending on which portion of the record was examined. It is hypothesized that this is the result of flocculation, affecting the two signals by different degrees, and that the significance or mechanism of the flocculation has some seasonal variability. In the earlier portion of the record (March), there is a clear difference that appears in the acoustic approach between ebb and flood periods, and this is not evident later in the record (May). The acoustic method has promise but it appears that characteristics of flocs that form and break apart may need to be accounted for to improve the power of the method. This may also be true of the optical method: both methods involve assuming that the sediment characteristics (size, size distribution, and shape) are constant.

  8. High-resolution remote sensing of water quality in the San Francisco Bay-Delta Estuary

    Science.gov (United States)

    Fichot, Cédric G.; Downing, Bryan D.; Bergamaschi, Brian; Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark C.; Thompson, David R.; Gierach, Michelle M.

    2015-01-01

    The San Francisco Bay–Delta Estuary watershed is a major source of freshwater for California and a profoundly human-impacted environment. The water quality monitoring that is critical to the management of this important water resource and ecosystem relies primarily on a system of fixed water-quality monitoring stations, but the limited spatial coverage often hinders understanding. Here, we show how the latest technology in visible/near-infrared imaging spectroscopy can facilitate water quality monitoring in this highly dynamic and heterogeneous system by enabling simultaneous depictions of several water quality indicators at very high spatial resolution. The airborne portable remote imaging spectrometer (PRISM) was used to derive high-spatial-resolution (2.6 × 2.6 m) distributions of turbidity, and dissolved organic carbon (DOC) and chlorophyll-a concentrations in a wetland-influenced region of this estuary. A filter-passing methylmercury vs DOC relationship was also developed using in situ samples and enabled the high-spatial-resolution depiction of surface methylmercury concentrations in this area. The results illustrate how high-resolution imaging spectroscopy can inform management and policy development in important inland and estuarine water bodies by facilitating the detection of point- and nonpoint-source pollution, and by providing data to help assess the complex impacts of wetland restoration and climate change on water quality and ecosystem productivity.

  9. Delta smelt: Life history and decline of a once abundant species in the San Francisco Estuary

    Science.gov (United States)

    Moyle, Peter B.; Brown, Larry R.; Durand, John R; Hobbs, James A.

    2016-01-01

    This paper reviews what has been learned about Delta Smelt and its status since the publication of The State of Bay-Delta Science, 2008 (Healey et al. 2008). The Delta Smelt is endemic to the upper San Francisco Estuary. Much of its historic habitat is no longer available and remaining habitat is increasingly unable to sustain the population. As a listed species living in the central node of California’s water supply system, Delta Smelt has been the focus of a large research effort to understand causes of decline and identify ways to recover the species. Since 2008, a remarkable record of innovative research on Delta Smelt has been achieved, which is summarized here. Unfortunately, research has not prevented the smelt’s continued decline, which is the result of multiple, interacting factors. A major driver of decline is change to the Delta ecosystem from water exports, resulting in reduced outflows and high levels of entrainment in the large pumps of the South Delta. Invasions of alien species, encouraged by environmental change, have also played a contributing role in the decline. Severe drought effects have pushed Delta Smelt to record low levels in 2014–2015. The rapid decline of the species and failure of recovery efforts demonstrate an inability to manage the Delta for the “co-equal goals” of maintaining a healthy ecosystem and providing a reliable water supply for Californians. Diverse and substantial management actions are needed to preserve Delta Smelt.

  10. Blood pressure and blood lead concentration in San Francisco MUNI bus drivers

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, D.S.

    1987-01-01

    San Francisco MUNI bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration (Pb-B) and blood pressure (BP) in 342 drivers. Two groups of subjects were identified. These subjects treated for hypertension (n = 54) and untreated subjects (n = 288). Systolic and diastolic BPs varied from 102-173 mmHg and from 61-105 mm Hg respectively in untreated subjects. They varied from 110-206 mmHg and from 73-127 mmHg respectively in treated subjects. The Pb-B varied from 2-15 {mu}g/dl in untreated subjects, and 2-25 {mu}g/dl in treated drivers. The relationship between BP and the logarithm of Pb-B was examined in each group separately using multiple regression techniques. Covariates included age, body mass index, sex, race, and caffeine intake. The regression coefficient relating systolic BP and In(Pb-B) was 1-2 mmHg/ln({mu}g/Dl) (90% C.I.: {minus}2,5) in untreated subjects. The relationship in treated subjects was too unstable to be accurately determined. The coefficients for diastolic BP were 2.0-2.5 mmHg/ln({mu}g/dl) (90% C.I.: 0.1,4.5) and 6 mmHg/ln({mu}g/dl) (90% C.I.: 2,11) in untreated and treated subjects respectively.

  11. Examining the Effects of Transphobic Discrimination and Race on HIV Risk Among Transwomen in San Francisco.

    Science.gov (United States)

    Arayasirikul, Sean; Wilson, Erin C; Raymond, Henry F

    2017-09-01

    Transwomen, in particular transwomen of color (TWOC), are among the most vulnerable populations at risk for HIV. This secondary analysis is organized using a gender minority stress framework to examine the effects of transphobic discrimination and race on HIV risk factors. We describe the sample of 149 HIV- adult transwomen in San Francisco and use binary logistic regression to examine the relationship between levels of transphobic discrimination and TWOC status on binge drinking and condomless receptive anal intercourse (CRAI), controlling for potential confounders. Those with high levels of transphobic discrimination had 3.59 fold greater odds of engaging in binge drinking compared to those who reported a low level of transphobic discrimination (95% CI 1.284-10.034; P = 0.015). TWOC had nearly threefold greater odds of CRAI compared to white transwomen (95% CI 1.048-8.464; P = 0.040). We discuss implications for gender minority stress research and future interventions for this population.

  12. Dietary mercury exposure to endangered California Clapper Rails in San Francisco Bay

    Science.gov (United States)

    Casazza, Michael L.; Ricca, Mark A.; Overton, Cory T.; Takekawa, John Y.; Merritt, Angela M.; Ackerman, Joshua T.

    2015-01-01

    California Clapper Rails (Rallus longirostris obsoletus) are an endangered waterbird that forage in tidal-marsh habitats that pose risks from mercury exposure. We analyzed total mercury (Hg) in six macro-invertebrate and one fish species representing Clapper Rail diets from four tidal-marshes in San Francisco Bay, California. Mercury concentrations among individual taxa ranged from lowest at Colma Creek (mean range: 0.09–0.2 μg/g dw) to highest at Cogswell (0.2–0.7), Laumeister (0.2–0.9) and Arrowhead Marshes (0.3–1.9). These spatial patterns for Hg matched patterns reported previously in Clapper Rail blood from the same four marshes. Over 25% of eastern mudsnails (Ilyanassa obsolete) and staghorn sculpin (Leptocottus armatus) exceeded dietary Hg concentrations (ww) often associated with avian reproductive impairment. Our results indicate that Hg concentrations vary considerably among tidal-marshes and diet taxa, and Hg concentrations of prey may provide an appropriate proxy for relative exposure risk for Clapper Rails.

  13. Analysis of pelagic species decline in the upper San Francisco Estuary using multivariate autoregressive modeling (MAR)

    Science.gov (United States)

    Mac Nally, Ralph; Thomson, James R.; Kimmerer, Wim J.; Feyrer, Frederick; Newman, Ken B.; Sih, Andy; Bennett, William A.; Brown, Larry; Fleishman, Erica; Culberson, Steven D.; Castillo, Gonzalo

    2010-01-01

    Four species of pelagic fish of particular management concern in the upper San Francisco Estuary, California, USA, have declined precipitously since ca. 2002: delta smelt (Hypomesus transpacificus), longfin smelt (Spirinchus thaleichthys), striped bass (Morone saxatilis), and threadfin shad (Dorosoma petenense). The estuary has been monitored since the late 1960s with extensive collection of data on the fishes, their pelagic prey, phytoplankton biomass, invasive species, and physical factors. We used multivariate autoregressive (MAR) modeling to discern the main factors responsible for the declines. An expert-elicited model was built to describe the system. Fifty-four relationships were built into the model, only one of which was of uncertain direction a priori. Twenty-eight of the proposed relationships were strongly supported by or consistent with the data, while 26 were close to zero (not supported by the data but not contrary to expectations). The position of the 2‰ isohaline (a measure of the physical response of the estuary to freshwater flow) and increased water clarity over the period of analyses were two factors affecting multiple declining taxa (including fishes and the fishes' main zooplankton prey). Our results were relatively robust with respect to the form of stock–recruitment model used and to inclusion of subsidiary covariates but may be enhanced by using detailed state–space models that describe more fully the life-history dynamics of the declining species.

  14. Preliminary location and age database for invertebrate fossils collected in the San Francisco Bay region, California

    Science.gov (United States)

    Parker, John M.; West, William B.; Malmborg, William T.; Brabb, Earl E.

    2003-01-01

    Most geologic maps published for central California in the past century have been made without the benefit of microfossils. The age of Cretaceous and Tertiary rocks in the structurally complex sedimentary formations of the Coast Ranges is critical in determining stratigraphic succession and in determining whether the juxtapositon of similar appearing formations means that a fault is present. Since the 1930’s, at least, oil company geologists have used microfossils to assist them in geologic mapping and in determining the environments of deposition of sedimentary rocks. This information has been confidential, but in the past 20 years the attitude of petroleum companies about this information has changed, and much material is now available. We report here on approximately 4,700 samples, largely foraminifers, from surface localities in the San Francisco Bay region of California. The information contained here can be used to update geologic maps, to analyze the depth and temperature of ocean water covering parts of California during the Mesozoic and Cenozoic eras, and for solving other geologic problems.

  15. Leadership lessons from curricular change at the University of California, San Francisco, School of Medicine.

    Science.gov (United States)

    Loeser, Helen; O'Sullivan, Patricia; Irby, David M

    2007-04-01

    After successive Liaison Committee on Medical Education accreditation reports that criticized the University of California, San Francisco, School of Medicine for lack of instructional innovation and curriculum oversight, the dean issued a mandate for curriculum reform in 1997. Could a medical school that prided itself on innovation in research and health care do the same in education? The authors describe their five-phase curriculum change process and correlate this to an eight-step leadership model. The first phase of curricular change is to establish a compelling need for change; it requires leaders to create a sense of urgency and build a guiding coalition to achieve action. The second phase of curriculum reform is to envision a bold new curriculum; leaders must develop such a vision and communicate it broadly. The third phase is to design curriculum and obtain the necessary approvals; this requires leaders to empower broad-based action and generate short-term wins. In the fourth phase, specific courses are developed for the new curriculum, and leaders continue to empower broad-based action, generate short-term wins, consolidate gains, and produce more change. During the fifth phase of implementation and evaluation, leaders need to further consolidate gains, produce more change, and anchor new approaches in the institution. Arising from this experience and the correlation of curricular change phases with leadership steps, the authors identify 27 specific leadership strategies they employed in their curricular reform process.

  16. Criminalization, legalization or decriminalization of sex work: what female sex workers say in San Francisco, USA.

    Science.gov (United States)

    Lutnick, Alexandra; Cohan, Deborah

    2009-11-01

    Sex work is a criminal offence in San Francisco, USA, and sex work advocates have so far unsuccessfully campaigned for decriminalizing it. Some groups argue that the decriminalization movement does not represent the voices of marginalized sex workers. Using qualitative and quantitative data from the Sex Worker Environmental Assessment Team Study, we investigated the perspectives and experiences of a range of female sex workers regarding the legal status of sex work and the impact of criminal law on their work experiences. Forty women were enrolled in the qualitative phase in 2004 and 247 women in the quantitative phase in 2006-07. Overall, the women in this study seemed to prefer a hybrid of legalization and decriminalization. The majority voiced a preference for removing statutes that criminalize sex work in order to facilitate a social and political environment where they had legal rights and could seek help when they were victims of violence. Advocacy groups need to explore the compromises sex workers are willing to make to ensure safe working conditions and the same legal protections afforded to other workers, and with those who are most marginalized to better understand their immediate needs and how these can be met through decriminalization.

  17. Exploring sexual health among female sexually transmitted disease clinic patients, San Francisco 2010.

    Science.gov (United States)

    Stephens, Sally C; Bernstein, Kyle T; Philip, Susan S

    2013-03-01

    Current data on sexual health in the United States is limited, in part, because of a lack of measurement tools. It is difficult for programs to develop a holistic approach to improving sexual health that is data-driven and evaluable without a tool that encompasses sexual health beyond the absence of disease. The objective of this study was to understand possible factors associated with sexual health and reported differences in sexual health among women. We conducted a survey measuring sexual health among women seeking care at the municipal sexually transmitted disease (STD) clinic in San Francisco between January 25, 2010, and June 15, 2010. Records were matched on variables including basic demographics, reason for visit, symptoms at visit, history of an STD, and STD diagnosis at the visit. A total of 822 women completed the questionnaire during the study period. Women reporting no recent sexual activity reported feeling more insecure, angry, isolated, and limited because of health compared with women with recent sexual activity. However, few differences were seen among women based on symptoms and diagnosis at visit. Given the minimal differences based on symptoms and disease, this suggests that there are other factors that impact the quality of life and sexual health. Creating tools that can be used to measure sexual health is a necessary first step for programs to understand the sexual health of a community. More broad-based assessments of sexual health in a variety of populations will be critical to identifying points of intervention and progress toward success.

  18. River discharge controls phytoplankton dynamics in the northern San Francisco Bay estuary

    Science.gov (United States)

    Cloern, J.E.; Alpine, A.E.; Cole, B.E.; Wong, R.L.J.; Arthur, J.F.; Ball, M.D.

    1983-01-01

    Phytoplankton dynamics in the upper reach of the northern San Francisco Bay estuary are usually characterized by low biomass dominated by microflagellates or freshwater diatoms in winter, and high biomass dominated by neritic diatoms in summer. During two successive years of very low river discharge (the drought of 1976-77), the summer diatom bloom was absent. This is consistent with the hypothesis that formation of the diatom population maximum is a consequence of the same physical mechanisms that create local maxima of suspended sediments in partially-mixed estuaries: density-selective retention of particles within an estuarine circulation cell. Because the estuary is turbid, calculated phytoplankton growth rates are small in the central deep channel but are relatively large in lateral shallow embayments where light limination is less severe. When river discharge falls within a critical range (100-350 m3 s-1) that positions the suspended particulate maximum adjacent to the productive shallow bays, the population of neritic diatoms increases. However, during periods of high discharge (winter) or during periods of very low discharge (drought), the suspended particulate maximum is less well-defined and is uncoupled (positioned downstream or upstream) from the shallow bays of the upper estuary, and the population of neritic diatoms declines. Hence, the biomass and community composition of phytoplankton in this estuary are controlled by river discharge. ?? 1983.

  19. A 13-year molecular epidemiological analysis of tuberculosis in San Francisco.

    Science.gov (United States)

    Cattamanchi, A; Hopewell, P C; Gonzalez, L C; Osmond, D H; Masae Kawamura, L; Daley, C L; Jasmer, R M

    2006-03-01

    We examined the molecular epidemiology of tuberculosis (TB) in San Francisco during a 13-year period encompassing the peak of TB resurgence and subsequent decline to historic low levels. To compare rates of TB caused either by rapid progression of recent Mycobacterium tuberculosis infection or by reactivation of latent infection. All TB cases reported from 1991 to 2003 were included. Genotyping was performed to identify clustered cases. The annual TB case rate decreased significantly from 50.8 to 28.8 cases/100000 persons from 1992 to 1999 (P < 0.0001). After 1999, no significant decrease was observed for the population as a whole or in any subgroup examined. Similarly, the rate of clustered cases decreased significantly from 1992 to 1999 (11.4 to 3.1 cases/100000, P < 0.0001). Although the rate of non-clustered cases also declined significantly (25.6 to 17.6 cases/100,000, P < 0.0001), there was a disproportionate reduction in clustered cases (94.7% vs. 50.8%, P < 0.0001). Neither clustered nor non-clustered cases decreased significantly after 1999. TB case rates reached a plateau despite ongoing application of control measures implemented in 1993. These data suggest that intensification of measures designed to identify and treat persons with latent TB infection will be necessary to further reduce TB incidence.

  20. The University of California, San Francisco Family Alcoholism Study. I. Design, methods, and demographics.

    Science.gov (United States)

    Vieten, Cassandra; Seaton, Kimberly L; Feiler, Heidid S; Wilhelmsen, Kirk C

    2004-10-01

    The University of California, San Francisco (UCSF) Family Alcoholism Study is a project designed to identify genetic loci that influence susceptibility to alcohol dependence and related phenotypes. Evidence supports a substantial genetic contribution to alcoholism susceptibility. However, the genetic epidemiology of alcoholism is complex, and its clinical manifestation is heterogeneous, making phenotype definition and demonstration of linkage difficult. Despite these challenges, some progress has been made toward identifying genes. The UCSF Family Alcoholism Study used a small family design, focusing primarily on sibling pairs and parent-child trios for linkage and association studies. Alcoholism-related phenotypes were assessed through interview and self-report questionnaires, with a focus on unidimensional and subphenotypical traits. Data-driven approaches to determining the most promising phenotypes for genetic analysis are being used. Both genome-wide scan and candidate gene approaches were used. The study enrolled 2154 individuals from 970 families from December 1995 through January 2003. Test-retest and interrater reliability for clinical data are very good, and power estimates suggest that this study will have adequate power by linkage analysis to detect loci with moderate effects. Design, methods, and sample demographics of the UCSF Family Study are presented, along with intrafamilial correlations for primary diagnostic phenotypes. Plans for genetic analysis, novel approaches to phenotype refinement, and the implications of ascertainment bias for heritability estimates are discussed.

  1. On Lagrangian Residual Currents With Applications in South San Francisco Bay, California

    Science.gov (United States)

    Cheng, Ralph T.; Casulli, Vincenzo

    1982-12-01

    The Lagrangian residual circulation has often been introduced as the sum of the Eulerian residual circulation and the Stokes' drift. Unfortunately, this definition of the Lagrangian residual circulation is conceptually incorrect because both the Eulerian residual circulation and the Stokes' drift are Eulerian variables. In this paper a classification of various residual variables are reviewed and properly defined. The Lagrangian residual circulation is then studied by means of a two-stage formulation of a computer model. The tidal circulation is first computed in a conventional Eulerian way, and then the Lagrangian residual circulation is determined by a method patterned after the method of markers and cells. To demonstrate properties of the Lagrangian residual circulation, application of this approach in South San Francisco Bay, California, is considered. With the aid of the model results, properties of the Eulerian and Lagrangian residual circulation are examined. It can be concluded that estimation of the Lagrangian residual circulation from Eulerian data may lead to unacceptable error, particularly in a tidal estuary where the tidal excursion is of the same order of magnitude as the length scale of the basin. A direction calculation of the Lagrangian residual circulation must be made and has been shown to be feasible.

  2. High-Resolution Remote Sensing of Water Quality in the San Francisco Bay-Delta Estuary.

    Science.gov (United States)

    Fichot, Cédric G; Downing, Bryan D; Bergamaschi, Brian A; Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark; Thompson, David R; Gierach, Michelle M

    2016-01-19

    The San Francisco Bay-Delta Estuary watershed is a major source of freshwater for California and a profoundly human-impacted environment. The water quality monitoring that is critical to the management of this important water resource and ecosystem relies primarily on a system of fixed water-quality monitoring stations, but the limited spatial coverage often hinders understanding. Here, we show how the latest technology in visible/near-infrared imaging spectroscopy can facilitate water quality monitoring in this highly dynamic and heterogeneous system by enabling simultaneous depictions of several water quality indicators at very high spatial resolution. The airborne portable remote imaging spectrometer (PRISM) was used to derive high-spatial-resolution (2.6 × 2.6 m) distributions of turbidity, and dissolved organic carbon (DOC) and chlorophyll-a concentrations in a wetland-influenced region of this estuary. A filter-passing methylmercury vs DOC relationship was also developed using in situ samples and enabled the high-spatial-resolution depiction of surface methylmercury concentrations in this area. The results illustrate how high-resolution imaging spectroscopy can inform management and policy development in important inland and estuarine water bodies by facilitating the detection of point- and nonpoint-source pollution, and by providing data to help assess the complex impacts of wetland restoration and climate change on water quality and ecosystem productivity.

  3. Measurements of gamma radiation levels and spectra in the San Francisco Bay Area

    Science.gov (United States)

    Lo, B. T.; Brozek, K. P.; Angell, C. T.; Norman, E. B.

    2011-10-01

    Much of the radiation received by an average person is emitted by naturally-occurring radioactive isotopes from the thorium, actinium, and uranium decay series, or potassium. In this study, we have measured gamma radiation levels at various locations in the San Francisco Bay Area and the UC Berkeley campus from spectra taken using an ORTEC NOMAD portable data acquisition system and a large-volume coaxial HPGe detector. We have identified a large number of gamma rays originating from natural sources. The most noticeable isotopes are 214Bi, 40K, and 208Tl. We have observed variations in counting rates by factors of two to five between different locations due to differences in local conditions - such as building, concrete, grass, and soil compositions. In addition, in a number of outdoor locations, we have observed 604-, 662-, and 795-keV gamma rays from 134,137Cs, which we attribute to fallout from the recent Fukushima reactor accident. The implications of these results will be discussed. This work was supported in part by a grant from the U. S. Dept. of Homeland Security.

  4. Willingness-to-accept Gamma knife radiosurgery for tinnitus among career San Francisco firefighters.

    Science.gov (United States)

    Pross, Seth E; Allen, Camille A; Hong, Oi Saeng; Cheung, Steven W

    2014-07-01

    Measure willingness-to-accept novel Gamma knife (GK) radiosurgery of the caudate nucleus to treat tinnitus among career firefighters who are at higher risk of hearing loss because of occupational noise exposure. Cross-sectional survey. A Web-based 80-item survey was distributed to 800 San Francisco firefighters and satisfactorily completed by 101 respondents. Demographic and work-related characteristics including occupational noise exposure, hearing handicap using the Hearing Handicap Inventory for Adults (HHIA), and tinnitus severity using the tinnitus functional index (TFI) were assessed. Willingness-to-accept GK radiosurgery for tinnitus was profiled using a 7-point scale for 6 decremental levels of expected tinnitus improvement. Respondents were a majority male (82%) and Caucasian (56%). Nearly all (95%) reported significant daily or weekly occupational noise exposure. Mean HHIA (16.3) and mean TFI (14.6) were mild. At the 100% (complete) tinnitus improvement level, more than 60% of respondents were "likely" willing-to-accept Gamma knife radiosurgery. At the 75% tinnitus improvement level, 43% of respondents were "likely" willing-to-accept GK radiosurgery. Below the 75% tinnitus improvement level, willingness-to-accept dropped off steeply. Gamma knife radiosurgery to area LC, a locus of the caudate nucleus, for tinnitus would be of interest to a large population with moderate or lower tinnitus distress. Should this innovative intervention be considered in the future, a rigorous clinical trial will be necessary to establish safety and efficacy.

  5. Case study: San Francisco's use of neighborhood indicators to encourage healthy urban development.

    Science.gov (United States)

    Bhatia, Rajiv

    2014-11-01

    Neighborhood indicators are quantitative measures of neighborhood quality, including measures of attributes such as crime, noise, proximity to parks, transit services, social capital, and student performance. In 2007 the San Francisco Department of Public Health, with broad public input, developed a comprehensive system of neighborhood indicators to inform, influence, and monitor decisions made by the Department of City Planning and other community development institutions. Local public agencies, businesses, and citizens' groups used the indicators to identify disparities in environmental and social conditions, inform and shape neighborhood land use plans, select appropriate sites for development projects, craft new environmental regulations, and justify demands on developers to make financial contributions to community infrastructure. Among other things, the use of indicators contributed to policies to prevent residential displacement, a city ordinance requiring stricter building ventilation standards in areas with high air pollution, and the redeployment of traffic police to high-injury corridors. Data that can be used to create neighborhood indicators are increasingly available, and participation by public health and health care institutions in the indicators' development, dissemination, and application could help improve several conditions that contribute to poor population health. Project HOPE—The People-to-People Health Foundation, Inc.

  6. Overdose prevention and naloxone prescription for opioid users in San Francisco.

    Science.gov (United States)

    Enteen, Lauren; Bauer, Joanna; McLean, Rachel; Wheeler, Eliza; Huriaux, Emalie; Kral, Alex H; Bamberger, Joshua D

    2010-12-01

    Opiate overdose is a significant cause of mortality among injection drug users (IDUs) in the United States (US). Opiate overdose can be reversed by administering naloxone, an opiate antagonist. Among IDUs, prevalence of witnessing overdose events is high, and the provision of take-home naloxone to IDUs can be an important intervention to reduce the number of overdose fatalities. The Drug Overdose Prevention and Education (DOPE) Project was the first naloxone prescription program (NPP) established in partnership with a county health department (San Francisco Department of Public Health), and is one of the longest running NPPs in the USA. From September 2003 to December 2009, 1,942 individuals were trained and prescribed naloxone through the DOPE Project, of whom 24% returned to receive a naloxone refill, and 11% reported using naloxone during an overdose event. Of 399 overdose events where naloxone was used, participants reported that 89% were reversed. In addition, 83% of participants who reported overdose reversal attributed the reversal to their administration of naloxone, and fewer than 1% reported serious adverse effects. Findings from the DOPE Project add to a growing body of research that suggests that IDUs at high risk of witnessing overdose events are willing to be trained on overdose response strategies and use take-home naloxone during overdose events to prevent deaths.

  7. Guidelines for sustainable building design: Recommendations from the Presidio of San Francisco energy efficiency design charrette

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.; Sartor, D.; Greenberg, S. [and others

    1996-05-01

    In 1994, the Bay Chapter of the Association of Energy Engineers{reg_sign} organized a two-day design charrette for energy-efficient redevelopment of buildings by the National Park Services (NPS) at the Presidio of San Francisco. This event brought together engineers, researchers, architects, government officials, and students in a participatory environment to apply their experience to create guidelines for the sustainable redesign of Presidio buildings. The venue for the charrette was a representative barracks building located at the Main Post of the Presidio. Examination of this building allowed for the development of design recommendations, both for the building and for the remainder of the facilities. The charrette was organized into a committee structure consisting of: steering, measurement and monitoring, modeling, building envelope and historic preservation (architectural), HVAC and controls, lighting, and presentation. Prior to the charrette itself, the modeling and measurement/monitoring committees developed substantial baseline data for the other committees during the charrette. An integrated design approach was initiated through interaction between the committees during the charrette. Later, committee reports were cross-referenced to emphasize whole building design and systems integration.

  8. Estuarine sedimentation, sediment character, and foraminiferal distribution in central San Francisco Bay, California

    Science.gov (United States)

    Chin, John L.; Woodrow, Donald L.; McGann, Mary; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2010-01-01

    Central San Francisco Bay is the deepest subembayment in the San Francisco Bay estuary and hence has the largest water volume of any of the subembayments. It also has the strongest tidal currents and the coarsest sediment within the estuary. Tidal currents are strongest over the west-central part of central bay and, correspondingly, this area is dominated by sand-size sediment. Much of the area east of a line from Angel Island to Alcatraz Island is characterized by muddy sand to sandy mud, and the area to the west of this line is sandy. The sand-size sediment over west-central bay furthermore is molded by the energetic tidal currents into bedforms of varying sizes and wavelengths. Bedforms typically occur in water depths of 15-25 m. High resolution bathymetry (multibeam) from 1997 and 2008 allow for subdivision of the west-central bayfloor into four basic types based on morphologic expression: featureless, sand waves, disrupted/man-altered, and bedrock knobs. Featureless and sand-wave morphologies dominate the bayfloor of west-central bay. Disrupted bayfloor has a direct association with areas that are undergoing alteration due to human activities, such as sand-mining lease areas, dredging, and disposal of dredge spoils. Change detection analysis, comparing the 1997 and 2008 multibeam data sets, shows that significant change has occurred in west-central bay during the roughly 10 years between surveys. The surveyed area lost about 5.45 million m3 of sediment during the decade. Sand-mining lease areas within west-central bay lost 6.77 million m3 as the bayfloor deepened. Nonlease areas gained 1.32 million m3 of sediment as the bayfloor shallowed slightly outside of sand-mining lease areas. Furthermore, bedform asymmetry did not change significantly, but some bedforms did migrate some tens of meters. Gravity cores show that the area east of Angel and Alcatraz Islands is floored by clayey silts or silty sand whereas the area to the west of the islands is floored

  9. Factors controlling floc settling velocity within San Francisco Bay, USA and comparisons with parameterisation approaches

    Science.gov (United States)

    Manning, Andrew; Schoellhamer, David

    2014-05-01

    Much of the sediment within San Francisco Bay (SFB) is cohesive and can therefore act as transport mechanism for pollutants which adsorb to clay minerals. Furthermore, muddy sediment can flocculate when resuspended; this significantly alters their transport characteristics, which poses a serious complication to the modelling of sediment pathways. The aim of this research was to determine the factors that affect floc settling velocity along a longitudinal transect in an estuary. We collected and analysed data on flocs and on potential controlling factors along a 147 km transect the length of San Francisco Bay, USA, on June 17th, 2008. The INSSEV-LF video system, which includes the novel video-based LabSFLOC instrument (developed by Manning) was used to measure floc diameters and settling velocities at 30 stations at a height of 0.7 m above the estuary bed. Floc sizes (D) ranged from 22 microns to 639 microns settling velocities (Ws) ranged between 0.04 mm/s to 15.8 mm/s during the longitudinal transect. Nearbed turbulent shear stresses throughout the transect duration were within the 0.2-0.5 Pa range which typically stimulates flocculation growth. Individual D-Ws-floc density plots suggest the suspended sediments encountered throughout SFB were composed of both mud and mixed sediment flocs. The macroflocs and microflocs (demarcation at 160 microns) sub-populations demonstrated parameterised settling velocities which spanned nearly double the range of the sample mean settling velocities (Ws_mean spanned 0.6-6 mm/s). The macroflocs tended to dominate the suspended mass (up to 77% of the ambient suspended solids concentration; SSC) from San Pablo Bay through to Carquinez Strait (the vicinity of the turbidity maximum zone). Microfloc mass was particularly significant (typically 60-100% of the SSC) in the northern section of South Bay and most of Central Bay. During slack tide, larger and faster settling flocs deposited, accounting for most of the longitudinal

  10. Synthesis of studies in the fall low-salinity zone of the San Francisco Estuary, September-December 2011

    Science.gov (United States)

    Brown, Larry R.; Baxter, Randall; Castillo, Gonzalo; Conrad, Louise; Culberson, Steven; Erickson, Gregg; Feyrer, Frederick; Fong, Stephanie; Gehrts, Karen; Grimaldo, Lenny; Herbold, Bruce; Kirsch, Joseph; Mueller-Solger, Anke; Slater, Steven B.; Sommer, Ted; Souza, Kelly; Van Nieuwenhuyse, Erwin

    2014-01-01

    In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecological Program to explore hypotheses about the ecological role of low-salinity habitat in the San Francisco Estuary—specifically, hypotheses about the importance of fall low-salinity habitat to the biology of delta smelt Hypomesus transpacificus, a species endemic to the San Francisco Estuary and listed as threatened or endangered under federal and state endangered species legislation. The Interagency Ecological Program is a consortium of 10 agencies that work together to develop a better understanding of the ecology of the Estuary and the effects of the State Water Project and Federal Central Valley Project operations on the physical, chemical, and biological conditions of the San Francisco Estuary. The fall low-salinity habitat investigation constitutes one of the actions stipulated in the Reasonable and Prudent Alternative issued with the 2008 Biological Opinion of the U.S. Fish and Wildlife Service, which called for adaptive management of fall Sacramento-San Joaquin Delta outflow following “wet” and “above normal” water years to alleviate jeopardy to delta smelt and adverse modification of delta smelt critical habitat. The basic hypothesis of the adaptive management of fall low-salinity habitat is that greater outflows move the low-salinity zone (salinity 1–6), an important component of delta smelt habitat, westward and that moving the low-salinity zone westward of its position in the fall of recent years will benefit delta smelt, although the specific mechanisms providing such benefit are uncertain. An adaptive management plan was prepared to guide implementation of the adaptive management of fall low-salinity habitat and to reduce uncertainty. This report has three major objectives:

  11. Forecasting selenium discharges to the San Francisco Bay-Delta Estuary: ecological effects of a proposed San Luis drain extension

    Science.gov (United States)

    Luoma, Samuel N.; Presser, Theresa S.

    2000-01-01

    During the next few years, federal and state agencies may be required to evaluate proposals and discharge permits that could significantly change selenium (Se) inputs to the San Francisco Bay-Delta Estuary (Bay-Delta), particularly in the North Bay (i.e., Suisun Bay and San Pablo Bay). These decisions may include discharge requirements for an extension of the San Luis Drain (SLD) to the estuary to convey subsurface agricultural drainage from the western San Joaquin Valley (SJV), a renewal of an agreement to allow the existing portion of the SLD to convey subsurface agricultural drainage to a tributary of the San Joaquin River (SJR) (coincident with changes in flow patterns of the lower SJR), and refinements to promulgated Se criteria for the protection of aquatic life for the estuary. Understanding the biotransfer of Se is essential to evaluating the fate and impact of proposed changes in Se discharges to the Bay-Delta. However, past monitoring programs have not addressed the specific protocols necessary for an element that bioaccumulates. Confusion about Se threats in the past have stemmed from failure to consider the full complexity of the processes that result in Se toxicity. Past studies show that predators are more at risk from Se contamination than their prey, making it difficult to use traditional methods to predict risk from environmental concentrations alone. In this report, we employ a novel procedure to model the fate of Se under different, potentially realistic load scenarios from the SJV. For each potential load, we progressively forecast the resulting environmental concentrations, speciation, transformation to particulate form, bioaccumulation by invertebrates, trophic transfer to predators, and effects in those predators. Enough is known to establish a first order understanding of effects should Se be discharged directly into the North Bay via a conveyance such as the SLD. Our approach uses 1) existing knowledge concerning the biogeochemical

  12. Geochemical assessment of metals and dioxin in sediment from the San Carlos Reservoir and the Gila, San Carlos, and San Francisco Rivers, Arizona

    Science.gov (United States)

    Church, Stan E.; Choate, LaDonna M.; Marot, Marci E.; Fey, David L.; Adams, Monique; Briggs, Paul H.; Brown, Zoe Ann

    2005-01-01

    In October 2004, we sampled stream-bed sediment, terrace sediment, and sediment from the San Carlos Reservoir to determine the spatial and chronological variation of six potentially toxic metals-Cu, Pb, Zn, Cd, As, and Hg. Water levels in the San Carlos Reservoir were at a 20-year low at an elevation of 2,409 ft (734.3 m). Four cores were taken from the reservoir: one from the San Carlos River arm, one from the Gila River arm, and two from the San Carlos Reservoir just west of the Pinal County line. Radioisotope chronometry (7Be, 137Cs, and 210Pb) conducted on sediment from the reservoir cores provides a good chronological record back to 1959. Chronology prior to that, during the 1950s, is based on our interpretation of the 137Cs anomaly in reservoir cores. During and prior to the 1950s, the reservoir was dry and sediment-accumulation rates were irregular; age control based on radioisotope data was not possible. We recovered sediment at the base of one 4-m-long core that may date back to the late 1930s. The sedimentological record contains two discrete events, one about 1978-83 and one about 1957, where the Cu concentration in reservoir sediment exceeded recommended sediment quality guidelines and should have had an effect on sensitive aquatic and benthic organisms. Concentrations of Zn determined in sediment deposited during the 1957(?) event also exceeded recommended sediment quality guidelines. Concentration data for Cu from the four cores clearly indicate that the source of this material was upstream on the Gila River. Lead isotope data, coupled with the geochemical data from a 2M HCl-1 percent H2O2 leach of selected sediment samples, show two discrete populations of data. One represents the dominant sediment load derived from the Safford Valley, and a second reflects sediment derived from the San Francisco River. The Cu concentration spikes in the reservoir cores have chemical and Pb isotope signatures that indicate that deposits in a porphyry copper deposit

  13. Geology and natural history of the San Francisco Bay area: A field-trip guidebook

    Science.gov (United States)

    Stoffer, Philip W.; Gordon, Leslie C.

    2001-01-01

    A National Association of Geoscience Teachers Far Western Section (NAGT-FWS) field conference is an ideal forum for learning about the geology and natural history of the San Francisco Bay area. We visit classic field sites, renew old friendships, and make new ones. This collection of papers includes field guides and road logs for all of the Bay-area trips held during the NAGT-FWS 2001 Fall Field Conference and supplemental chapters on other aspects of the area’s natural and human history. The trips touch on many aspects of the geology and natural hazards of the Bay area, especially urban problems associated with living on an active tectonic plate margin: earthquake faults, coastal erosion, landslides, and the utilization of land and natural resources. We hope this conference not only provides a two-day learning opportunity for conference participants but that students and educators will use this field guidebook for future teaching and research.Many thanks are due to the U.S. Geological Survey (USGS) and San José State University (SJSU) for cohosting the conference. We are grateful to each of the field trip leaders for preparing the trips and writing the accompanying guides. We especially appreciate the many hours put in by the guidebook reviewers, Robert I. Tilling (USGS) and Paula Messina (SJSU), and to the USGS Western Publications Group for editing, layout, and web posting. Additional guidebook contributions include articles by John Galloway, Scott Starratt, Page Mosier, and Susan Toussaint. During the conference guest speakers include Robert I. Tilling (USGS Volcano Hazards Team) and Ross Stein (USGS Earthquake Hazards Team). Workshops prepared for the conference include GIS in the classroom, using USGS data by John Vogel (USGS) and Paula Messina (SJSU), and The Best of BAESI (Bay Area Earth Science Institute), a teacher training organization under the direction of Ellen Metzger (SJSU) and Richard Sedlock (SJSU). The conference provides an opportunity to

  14. Fire history of the San Francisco East Bay region and implications for landscape patterns

    Science.gov (United States)

    Keeley, J.E.

    2005-01-01

    The San Francisco East Bay landscape is a rich mosaic of grasslands, shrublands and woodlands that is experiencing losses of grassland due to colonization by shrubs and succession towards woodland associations. The instability of these grasslands is apparently due to their disturbance-dependent nature coupled with 20th century changes in fire and grazing activity. This study uses fire history records to determine the potential for fire in this region and for evidence of changes in the second half of the 20th century that would account for shrubland expansion. This region has a largely anthropogenic fire regime with no lightning-ignited fires in most years. Fire suppression policy has not excluded fire from this region; however, it has been effective at maintaining roughly similar burning levels in the face of increasing anthropogenic fires, and effective at decreasing the size of fires. Fire frequency parallels increasing population growth until the latter part of the 20th century, when it reached a plateau. Fire does not appear to have been a major factor in the shrub colonization of grasslands, and cessation of grazing is a more likely immediate cause. Because grasslands are not under strong edaphic control, rather their distribution appears to be disturbance-dependent, and natural lightning ignitions are rare in the region, I hypothesize that, before the entrance of people into the region, grasslands were of limited extent. Native Americans played a major role in creation of grasslands through repeated burning and these disturbance-dependent grasslands were maintained by early European settlers through overstocking of these range lands with cattle and sheep. Twentieth century reduction in grazing, coupled with a lack of natural fires and effective suppression of anthropogenic fires, have acted in concert to favor shrubland expansion.

  15. Recent warming in the San Francisco Bay and the California coastal ocean

    Science.gov (United States)

    Chao, Yi; Farrara, John; Zhang, Carrie

    2017-05-01

    During 2014 exceptionally warm water temperatures developed across a wide area off the California coast and within San Francisco Bay (SFB) and persisted through the middle of 2016. Observations and numerical model output are used to document this warming and its origins. The coastal warming was mostly confined to the upper 100 meters of the ocean and was manifested strongly in the two leading modes of upper ocean (0-100 m) temperature variability in the extra-tropical eastern Pacific. Observations in the suggest that the coastal warming in 2014 propagated into nearshore regions from the west and later indicate a warming influence that propagates from south to north into the region associated with the 2015-16 El Niño event. An analysis of the upper ocean (0-100 m) heat budget in a Regional Ocean Modeling System hindcast simulation confirmed this scenario. The results from a set of sensitivity runs with the model in which the lateral boundary conditions varied supports the conclusions drawn from the heat budget analysis. Concerning the warming in the SFB, an examination of the observations and the heat budget in an unstructured-grid numerical model simulation suggests that the warming during the second half of 2014 and early 2016 originates in the adjacent California coastal ocean and propagates through the Golden Gate into the Bay. The finding that the coastal and Bay warming are due to the relatively slow propagation of signals from remote sources raise the possibility that such warming events may be predictable several months in advance.

  16. Holocene Climates and Connections between the San Francisco Bay Estuary and its Watershed: A Review

    Directory of Open Access Journals (Sweden)

    Frances Malamud-Roam

    2007-02-01

    Full Text Available Climate over the watershed of the San Francisco Bay Delta estuary system varies on a wide range of space and time scales, and affects downstream estuarine ecosystems. The historical climate has included mild to severe droughts and torrential rains accompanied by flooding, providing important lessons for present-day resource managers. Paleoclimate records spanning the last 10,000 years, synthesized across the Estuary, watershed and key regions beyond, provide a basis for increased understanding of how variable California’s climate can be and how it affects the Bay Delta system. This review of paleoclimate records reveals a gradual warming and drying in California from about 10,000 years to about 4,000 years before present. During this period, the current Bay and Delta were inundated by rising sea level so that by 4,000 years ago the Bay and Delta had taken on much of their present shape and extent. Between about 4,000 and 2,000 years ago, cooler and wetter conditions prevailed in the watershed, lowering salinity in the Estuary and altering local ecosystems. Those wetter conditions gave way to increasing aridity during the past 2,000 years, a general trend punctuated by occasional prolonged and severe droughts and occasional unusually wet, cool periods. California’s climate since A.D. 1850 has been unusually stable and benign, compared to climate variations during the previous 2,000 or more years. Thus, climate variations in California’s future may be even more (perhaps much more challenging than those of the past 100 years. To improve our understanding of these past examples of climate variability in California, and of the linkages between watershed climate and estuarine responses, greater emphases on paleoclimate records in and around the Estuary, improved temporal resolutions in several record types, and linked watershed-estuary paleo-modeling capabilities are needed.

  17. Linkage scan of nicotine dependence in the University of California, San Francisco (UCSF) Family Alcoholism Study.

    Science.gov (United States)

    Gizer, I R; Ehlers, C L; Vieten, C; Seaton-Smith, K L; Feiler, H S; Lee, J V; Segall, S K; Gilder, D A; Wilhelmsen, K C

    2011-04-01

    Nicotine dependence has been shown to represent a heritable condition, and several research groups have performed linkage analysis to identify genomic regions influencing this disorder though only a limited number of the findings have been replicated. In the present study, a genome-wide linkage scan for nicotine dependence was conducted in a community sample of 950 probands and 1204 relatives recruited through the University of California, San Francisco (UCSF) Family Alcoholism Study. A modified version of the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) with additional questions that probe nicotine use was used to derive DSM-IV nicotine dependence diagnoses. A locus on chromosome 2q31.1 at 184 centiMorgans nearest to marker D2S2188 yielded a logarithm (base 10) of odds (LOD) score of 3.54 (point-wise empirical p=0.000012). Additional peaks of interest were identified on chromosomes 2q13, 4p15.33-31, 11q25 and 12p11.23-21. Follow-up analyses were conducted examining the contributions of individual nicotine dependence symptoms to the chromosome 2q31.1 linkage peak as well as examining the relationship of this chromosomal region to alcohol dependence. The present report suggests that chromosome 2q31.1 confers risk to the development of nicotine dependence and that this region influences a broad range of nicotine dependence symptoms rather than a specific facet of the disorder. Further, the results show that this region is not linked to alcohol dependence in this population, and thus may influence nicotine dependence specifically.

  18. Remotely Sensing Pollution: Detection and Monitoring of PCBs in the San Francisco Bay

    Science.gov (United States)

    Hilton, A.; Kudela, R. M.; Bausell, J.

    2016-12-01

    While the EPA banned polychlorinated biphenyls (PCBs) in 1977, they continue to persist in San Francisco Bay (SF Bay), often at dangerously high concentrations due to their long half-life. However, in spite of their associated health and environmental risks, PCB monitoring within SF Bay is extremely limited, due in large part to the high costs, both in terms of labor and capital that are associated with it. In this study, a cost effective alternative to in-situ PCB sampling is presented by demonstrating the feasibility of PCB detection via remote sensing. This was done by first establishing relationships between in-situ measurements of sum of 40 PCB concentrations and total suspended sediment concentration (SSC) collected from 1998-2006 at 37 stations distributed throughout SF Bay. A correlation was discovered for all stations at (R2 =0.32), which improved markedly upon partitioning stations into north bay, (R2 =0.64), central bay (R2 =0.80) and south bay (R2 =0.52) regions. SSC was then compared from three USGS monitoring stations with temporally consistent Landsat 8 imagery. The resulting correlation between Landsat 8 (Rrs 654) and SSC measured at USGS stations (R2 =0.50) was validated using an Airborne Visible/ Infrared Imaging Spectrometer (AVIRIS) image. The end product is a two-step empirical algorithm that can derive PCB from Landsat 8 imagery within SF Bay. This algorithm can generate spatial PCB concentration maps for SF Bay, which can in turn be utilized to increase ability to forecast PCB concentration. The observation that correlation between AVIRIS (Rrs 657) and SSC was stronger than that of Landsat 8 suggests that the accuracy of this algorithm could be enhanced with improved atmospheric correction.

  19. The observed relationship between wave conditions and beach response, Ocean Beach, San Francisco, CA

    Science.gov (United States)

    Hansen, J.E.; Barnard, P.L.

    2009-01-01

    Understanding how sandy beaches respond to storms is critical for effective sediment management and developing successful erosion mitigation efforts. However, only limited progress has been made in relating observed beach changes to wave conditions, with one of the major limiting factors being the lack of temporally dense beach topography and nearshore wave data in most studies. This study uses temporally dense beach topographic and offshore wave data to directly link beach response and wave forcing with generally good results. Ocean Beach is an open coast high-energy sandy beach located in San Francisco, CA, USA. From April 2004 through the end of 2008, 60 three-dimensional topographic beach surveys were conducted on approximately a monthly basis, with more frequent “short-term surveys during the winters of 2005-06 and 2006-07. Shoreline position data from the short-term surveys show good correlation with offshore wave height, period, and direction averaged over several days prior to the survey (mean R*=0.54 for entire beach). There is, however, considerable alongshore variation in model performance, with R- values ranging from 0.81 to 0.19 for individual sections of the beach. After wave height, the direction of wave approach was the most important factor in determining the response of the shoreline, followed by wave period. Our results indicate that an empirical predictive model of beach response to wave conditions at Ocean Beach is possible with frequent beach mapping and wave data, and that such a model could be useful to coastal managers. 

  20. Anomalously Low pCO2 Measured in the San Francisco Estuary

    Science.gov (United States)

    Fuller, J. R.; Wilkerson, F.; Parker, A. E.; Marchi, A.

    2008-12-01

    Estuaries have been identified as potential net sources of CO2 to the atmosphere. Bacterial respiration of organic matter entering the estuary leads to supersaturated levels of pCO2. The southern embayment of the San Francisco Estuary (SFE) is no exception due in part to wastewater treatment practices. Persistently high levels of pCO2 between 600 and 1000 μatm have been reported for this embayment by the U.S. Geological Survey over the period 1976-1980 and more recently (2007-2008) by the authors. However, both studies also found notable exceptions to the high pCO2 levels during the spring phytoplankton bloom. An average level of 375 μatm, slightly above the contemporary atmospheric level, was observed during an April 1980 transect. Our recent measurements over the same transect have observed an even greater drawdown of pCO2 to as low as 175 μatm. In addition the pCO2 drawdown persisted from early March 2008 until the end of May. These anomalously low levels correspond directly with an algal bloom as evidenced by high concentrations of chlorophyll a and supersaturated dissolved oxygen. To our knowledge these are the lowest levels reported for the SFE and they indicate that portions of the estuary are a sink for atmospheric CO2 during bloom conditions. The hydrology of the southern embayment is dominated at times by the input of wastewater which is often treated to the advanced secondary level with inorganic nitrate as the product. This possibly contributes to a healthy estuarine algal population that helps to maintain current pCO2 levels in the SFE to those of 30 years ago despite significant urban growth around the estuary over that period. These findings have major implications both to estuarine management and to estimates of the estuarine component in global air-sea CO2 exchange

  1. Selenium bioaccumulation and body condition in shorebirds and terns breeding in San Francisco Bay, California, USA

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2009-01-01

    The present study evaluated Se bioaccumulation in four waterbird species (n = 206 birds) that breed within San Francisco Bay, California, USA: American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), Forster's terns (Sterna forsteri), and Caspian terns (Hydroprogne caspia). Selenium concentrations were variable and influenced by several factors, including species, region, reproductive stage, age, and sex. Adult Se concentrations (μg/g dry wt) in livers ranged from 3.07 to 48.70 in avocets (geometric mean ± standard error, 7.92 ± 0.64), 2.28 to 41.10 in stilts (5.29 ± 0.38), 3.73 to 14.50 in Forster's terns (7.13 ± 0.38), and 4.77 to 14.40 in Caspian terns (6.73 ± 0.78). Avocets had higher Se concentrations in the North Bay compared to the South Bay, whereas stilt Se concentrations were similar between these regions and Forster's terns had lower Se concentrations in the North Bay compared to the South Bay. Female avocets had higher Se concentrations than male avocets, but this was not the case for stilts and Forster's terns. Of the factors assessed, reproductive stage had the most consistent effect among species. Prebreeding birds tended to have higher liver Se concentrations than breeding birds, but this trend was statistically significant only for Forster's terns. Forster's tern chicks had lower Se concentrations than Forster's tern adults, whereas avocet and stilt adults and chicks were similar. Additionally, body condition was negatively related to liver Se concentrations in Forster's tern adults but not in avocet, stilt, or Caspian tern adults and chicks. These variable results illustrate the complexity of Se bioaccumulation and highlight the need to sample multiple species and examine several factors to assess the impact of Se on wildlife.

  2. Impact of San Francisco's toy ordinance on restaurants and children's food purchases, 2011-2012.

    Science.gov (United States)

    Otten, Jennifer J; Saelens, Brian E; Kapphahn, Kristopher I; Hekler, Eric B; Buman, Matthew P; Goldstein, Benjamin A; Krukowski, Rebecca A; O'Donohue, Laura S; Gardner, Christopher D; King, Abby C

    2014-07-17

    In 2011, San Francisco passed the first citywide ordinance to improve the nutritional standards of children's meals sold at restaurants by preventing the giving away of free toys or other incentives with meals unless nutritional criteria were met. This study examined the impact of the Healthy Food Incentives Ordinance at ordinance-affected restaurants on restaurant response (eg, toy-distribution practices, change in children's menus), and the energy and nutrient content of all orders and children's-meal-only orders purchased for children aged 0 through 12 years. Restaurant responses were examined from January 2010 through March 2012. Parent-caregiver/child dyads (n = 762) who were restaurant customers were surveyed at 2 points before and 1 seasonally matched point after ordinance enactment at Chain A and B restaurants (n = 30) in 2011 and 2012. Both restaurant chains responded to the ordinance by selling toys separately from children's meals, but neither changed their menus to meet ordinance-specified nutrition criteria. Among children for whom children's meals were purchased, significant decreases in kilocalories, sodium, and fat per order were likely due to changes in children's side dishes and beverages at Chain A. Although the changes at Chain A did not appear to be directly in response to the ordinance, the transition to a more healthful beverage and default side dish was consistent with the intent of the ordinance. Study results underscore the importance of policy wording, support the concept that more healthful defaults may be a powerful approach for improving dietary intake, and suggest that public policies may contribute to positive restaurant changes.

  3. Predicted Surface Displacements for Scenario Earthquakes in the San Francisco Bay Region

    Science.gov (United States)

    Murray-Moraleda, Jessica R.

    2008-01-01

    In the immediate aftermath of a major earthquake, the U.S. Geological Survey (USGS) will be called upon to provide information on the characteristics of the event to emergency responders and the media. One such piece of information is the expected surface displacement due to the earthquake. In conducting probabilistic hazard analyses for the San Francisco Bay Region, the Working Group on California Earthquake Probabilities (WGCEP) identified a series of scenario earthquakes involving the major faults of the region, and these were used in their 2003 report (hereafter referred to as WG03) and the recently released 2008 Uniform California Earthquake Rupture Forecast (UCERF). Here I present a collection of maps depicting the expected surface displacement resulting from those scenario earthquakes. The USGS has conducted frequent Global Positioning System (GPS) surveys throughout northern California for nearly two decades, generating a solid baseline of interseismic measurements. Following an earthquake, temporary GPS deployments at these sites will be important to augment the spatial coverage provided by continuous GPS sites for recording postseismic deformation, as will the acquisition of Interferometric Synthetic Aperture Radar (InSAR) scenes. The information provided in this report allows one to anticipate, for a given event, where the largest displacements are likely to occur. This information is valuable both for assessing the need for further spatial densification of GPS coverage before an event and prioritizing sites to resurvey and InSAR data to acquire in the immediate aftermath of the earthquake. In addition, these maps are envisioned to be a resource for scientists in communicating with emergency responders and members of the press, particularly during the time immediately after a major earthquake before displacements recorded by continuous GPS stations are available.

  4. MODELADO DE PARTÍCULAS PM10 Y PM2.5 MEDIANTE REDES NEURONALES ARTIFICIALES SOBRE CLIMA TROPICAL DE SAN FRANCISCO DE CAMPECHE, MÉXICO

    Directory of Open Access Journals (Sweden)

    Alberto Antonio Espinosa Guzmán

    Full Text Available In this paper, a computational methodology based on Artificial Neural Networks (ANN was developed to estimate the index of PM10 and PM2.5 concentration in air of San Francisco de Campeche city. A three layer ANN architecture was trained using an experimental database composed by days of the week, time of day, ambient temperature, atmospheric pressure, wind speed, wind direction, relative humidity, and solar radiation. The best ANN architecture, composed by 30 neurons in hidden layer, was obtained using the Levenberg-Marquardt (LM optimization algorithm, logarithmic sigmoid and linear transfer functions. Model results generate predictions with a determination coefficient of 93.01% and 90.10% for PM2.5 and PM10, respectively. The proposed methodology can be implemented in several studies as public health, environmental studies, urban development, and degradation of historical monuments.

  5. 75 FR 8106 - Don Edwards San Francisco Bay National Wildlife Refuge, Alameda, Santa Clara, and San Mateo...

    Science.gov (United States)

    2010-02-23

    ..., and San Mateo Counties, CA AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of intent to... located in Alameda, Santa Clara, and San Mateo Counties of California. We provide this notice in... Clara, and San Mateo Counties, CA. This notice complies with our CCP policy to (1) advise other Federal...

  6. How Will the San Francisco Bay-Delta Ecosystem Respond to Climate Change and Continued Population Growth?

    Science.gov (United States)

    Cloern, J.

    2008-12-01

    Programs to ensure sustainability of coastal ecosystems and the biological diversity they harbor require ecological forecasting to assess habitat transformations from the coupled effects of climate change and human population growth. A multidisciplinary modeling project (CASCaDE) was launched in 2007 to develop 21st-century visions of the Sacramento-San Joaquin Delta and San Francisco Bay under four scenarios of climate change and increasing demand for California's water resource. The process begins with downscaled projections of daily weather from GCM's and routes these to a watershed model that computes runoff and an operations model that computes inflows to the Bay-Delta. Hydrologic and climatic outputs, including sea level rise, drive models of tidal hydrodynamics-salinity-temperature in the Delta, sediment inputs and evolving geomorphology of San Francisco Bay. These projected habitat changes are being used to address priority questions asked by resource managers: How will changes in seasonal streamflow, salinity and water temperature, frequency of extreme weather and hydrologic events, and geomorphology influence the sustainability of native species that depend upon the Bay-Delta and the ecosystem services it provides?

  7. A Modeling Study of the San Francisco Bay and Delta Ecosystem in High and Low River Flow Years

    Science.gov (United States)

    Liu, Q.; Rao, S. A.; Chai, F.; Dugdale, R. C.; Wilkerson, F. P.; Chao, Y.; Zhang, H.

    2016-02-01

    A coupled physical-biogeochemical model is used to study the nutrient and biomass cycles in the San Francisco Bay and Delta Ecosystem (SFE). With high population density, SFE has important interplay with human population and economics. To assist the ecosystem-based management and ecological risk assessment for the California fisheries and water management, we study the nutrient and biomass cycles in the San Francisco Bay by coupling the Carbon, Silicate, and Nitrogen Ecosystem (CoSiNE) model with an unstructured grid, Semi-Implicit Cross-scale Hydroscience Integrated System Model (SCHISM). The model is constrained by USGS water quality observation for the Sacramento, San Joaquin, Napa rivers and the Coyote Creek sewage plant discharge, and tested successfully by the comparisons with USGS water quality observations. This study examines the bay's response to river forcing by simulating two contrasting years, 2011 (a high river flow year) and 2012 (a low river flow year). In addition, an 11-year simulation from 2004 to 2015 is conducted to investigate the long-term cycle of the bay nutrients and biomass.

  8. Probabilistic Methodology for Estimation of Number and Economic Loss (Cost) of Future Landslides in the San Francisco Bay Region, California

    Science.gov (United States)

    Crovelli, Robert A.; Coe, Jeffrey A.

    2008-01-01

    The Probabilistic Landslide Assessment Cost Estimation System (PLACES) presented in this report estimates the number and economic loss (cost) of landslides during a specified future time in individual areas, and then calculates the sum of those estimates. The analytic probabilistic methodology is based upon conditional probability theory and laws of expectation and variance. The probabilistic methodology is expressed in the form of a Microsoft Excel computer spreadsheet program. Using historical records, the PLACES spreadsheet is used to estimate the number of future damaging landslides and total damage, as economic loss, from future landslides caused by rainstorms in 10 counties of the San Francisco Bay region in California. Estimates are made for any future 5-year period of time. The estimated total number of future damaging landslides for the entire 10-county region during any future 5-year period of time is about 330. Santa Cruz County has the highest estimated number of damaging landslides (about 90), whereas Napa, San Francisco, and Solano Counties have the lowest estimated number of damaging landslides (5?6 each). Estimated direct costs from future damaging landslides for the entire 10-county region for any future 5-year period are about US $76 million (year 2000 dollars). San Mateo County has the highest estimated costs ($16.62 million), and Solano County has the lowest estimated costs (about $0.90 million). Estimated direct costs are also subdivided into public and private costs.

  9. Under the Golden Gate bridge: views of the sea floor near the entrance to San Francisco Bay, California

    Science.gov (United States)

    Dartnell, Peter; Barnard, Patrick L.; Chin, John L.; Hanes, Daniel; Kvitek, Rikk G.; Iampietro, Pat J.; Gardner, James V.

    2006-01-01

    San Francisco Bay in Northern California is one of the largest and most altered estuaries within the United States. The sea floor within the bay as well as at its entrance is constantly changing due to strong tidal currents, aggregate mining, dredge disposal, and the creation of new land using artificial fill. Understanding this dynamic sea floor is critical for addressing local environmental issues, which include defining pollution transport pathways, deciphering tectonics, and identifying benthic habitats. Mapping commercial interests such as safe ship navigation and dredge disposal is also significantly aided by such understanding. Over the past decade, the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), and California State University, Monterey Bay (CSUMB) in cooperation with the U.S. Army Corps of Engineers (USACOE) and the Center for Integrative Coastal Observation, Research and Education (CICORE) have partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. These sonar systems can continuously map to produce 100 percent coverage of the sea floor at meter-scale resolution and thus produce an unprecedented view of the floor of the bay. This poster shows views of the sea floor in west-central San Francisco Bay around Alcatraz and Angel Islands, underneath the Golden Gate Bridge, and through its entrance from the Pacific Ocean. The sea floor is portrayed as a shaded relief surface generated from the multibeam data color-coded for depth from light blues for the shallowest values to purples for the deepest. The land regions are portrayed by USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). The water depths have a 4x vertical exaggeration while the land areas have a 2x vertical exaggeration.

  10. Sand sources and transport pathways for the San Francisco Bay coastal system, based on X-ray diffraction mineralogy

    Science.gov (United States)

    Hein, James R.; Mizell, Kira; Barnard, Patrick L.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    The mineralogical compositions of 119 samples collected from throughout the San Francisco Bay coastal system, including bayfloor and seafloor, area beaches, cliff outcrops, and major drainages, were determined using X-ray diffraction (XRD). Comparison of the mineral concentrations and application of statistical cluster analysis of XRD spectra allowed for the determination of provenances and transport pathways. The use of XRD mineral identifications provides semi-quantitative compositions needed for comparisons of beach and offshore sands with potential cliff and river sources, but the innovative cluster analysis of XRD diffraction spectra provides a unique visualization of how groups of samples within the San Francisco Bay coastal system are related so that sand-sized sediment transport pathways can be inferred. The main vector for sediment transport as defined by the XRD analysis is from San Francisco Bay to the outer coast, where the sand then accumulates on the ebb tidal delta and also moves alongshore. This mineralogical link defines a critical pathway because large volumes of sediment have been removed from the Bay over the last century via channel dredging, aggregate mining, and borrow pit mining, with comparable volumes of erosion from the ebb tidal delta over the same period, in addition to high rates of shoreline retreat along the adjacent, open-coast beaches. Therefore, while previously only a temporal relationship was established, the transport pathway defined by mineralogical and geochemical tracers support the link between anthropogenic activities in the Bay and widespread erosion outside the Bay. The XRD results also establish the regional and local importance of sediment derived from cliff erosion, as well as both proximal and distal fluvial sources. This research is an important contribution to a broader provenance study aimed at identifying the driving forces for widespread geomorphic change in a heavily urbanized coastal-estuarine system.

  11. On the Trail of Missing Heat: Forward Gravity Modeling of the San Francisco Volcanic Field, Northern Arizona

    Science.gov (United States)

    Fry, B. N.; Morgan, P.

    2003-12-01

    The San Francisco volcanic field is a Quaternary field in northern Arizona, the age and size of which suggests there is a high possibility for an associated exploitable high temperature geothermal resource. Sunset Crater, the youngest dated feature in the field, erupted less than 1000 years ago. The youngest felsic volcanism in the area, located near Strawberry Crater, has been dated at about 51,000 years b.p. Felsic magmas are viscous, and therefore felsic magmatism is generally associated with upper crustal plutons, whereas mafic magmas commonly form surface flows. Heat from felsic magmatism tends to remain near subsurface ponds of the magma. Felsic magmatic systems can sustain substantial geothermal heat for tens to hundreds of thousands of years after emplacement. Knowledge of the quantity and distribution of felsic magmatism is therefore paramount to understanding the geothermal potential of the field. Surface heat flow in the study area ranges from ˜20 to ˜50 mW/m2, anomalously low for the region. Hydrological characteristics of the San Francisco volcanic field are thought to mask increased surface heat flow from the magmatic system. The deep water table (>300m) and a 2-level hydraulic system prevent characteristic surface manifestations of hydrothermal potential, such as hot springs and elevated surface heat flow. Lack of these thermal features at the surface precludes analysis of the resource based solely on surficial mapping and measurements. Forward modeling of the gravity field of a 50 km x 45 km area covering the eastern San Francisco volcanic field has been completed. Results suggest that a large felsic body ( ˜-0.15 g/cc contrast) trends northeastward under the Sugarloaf Mountain-O'Leary Peak-Strawberry Crater magmatic trend. This trend parallels a regional basement fabric, likely of early- to middle-Proterozoic origin. These results are being correlated with new surface geologic mapping and radiometric dating of young felsic volcanic rocks to

  12. Geographies of displacement: Latina/os, oral history, and the politics of gentrification in San Francisco's Mission District.

    Science.gov (United States)

    Mirabal, Nancy Raquel

    2009-05-01

    During the 1990s and early 2000s, working-class and poor neighborhoods in San Francisco underwent dramatic economic and racial changes. One of the most heavily gentrified neighborhoods was the Mission District. As a result of local politics, housing and rental policies, real estate speculation, and development, thousands of Latina/o families were displaced. Using oral historical and ethnographic methodologies, print media, archival sources, and policy papers, this article traces the gentrification of the Mission District from the perspective of the Latina/o community. It also examines how gentrification was articulated as a positive turn within the larger public discourse on space and access.

  13. Individual-level and Population-level Historical Prey Demand of San Francisco Estuary Striped Bass Using a Bioenergetics Model

    OpenAIRE

    Loboschefsky, Erik; Benigno, Gina; Sommer, Ted; Rose, Kenneth; Ginn, Timothy; Massoudieh, Arash; Loge, Frank

    2012-01-01

    Striped bass are both a major predator of native fishes and support a recreational fishery in the San Francisco Estuary (the estuary). Quantifying their demands on their prey is important for understanding long-term trends of fish in the estuary. In this study, we: (i) applied a bioenergetics model of sub-adult (age 1 and age 2) and adult (age 3+) striped bass (Morone saxatilis) to quantify long-term consumption patterns from 1969 through 2004 in the estuary; (ii) developed a method to estima...

  14. Towards a real-time forecasting system for the San Francisco bay/estuary and rive delta

    Science.gov (United States)

    Zhang, H.; Chao, Y.; Farrara, J. D.; Chai, F.; Dugdale, R. C.; Wilkerson, F. P.; Zhang, Y. J.; Ateljevich, E.

    2016-02-01

    An unstructured grid model based on SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) is being developed to address complex resource management questions in the San Francisco Bay/Estuary and Sacramento-San Joaquin River Delta (Bay-Delta). The air-sea fluxes are provided by a high-resolution (3-km) mesoscale atmospheric model (COAMPS). The river discharge data are used as the lateral boundary condition upstream. The coastal ocean boundary condition is derived from a structured grid California coastal ocean model based on ROMS. Results from a 10-year (2004-2015) hindcast will be presented focusing on variability on multiple time scales from tides, weather, annual to interannual. The recent warming during 2014 in response to the Pacific and California coastal warming will be described. Adding a sediment transport model as well as a biogeochemical/ecosystem model will be discussed.

  15. Transformaciones del modelo Neogranadino de parroquialización. El caso de la Parroquia San Francisco Xavier de Piedecuesta

    Directory of Open Access Journals (Sweden)

    Luis Rubén Pérez Pinzón

    2013-01-01

    Full Text Available El artículo analiza los fundamentos canónigos, las razones virreinales y los rituales eclesiásticos que justificaron las fundaciones parroquiales del siglo XVIII. Para ello se enfatiza en el modelo de urbanismo de las autoridades borbónicas que sustituyó la práctica de fundaciones de ciudades y villas de los siglos XVI y XVII a partir de capitulaciones. Modelo de necesidades demostradas, visitas a las instituciones virreinales y verificación de méritos que se puede comprobar desde el caso de la parroquia moderna de San Francisco Xavier del Pie de la Cuesta (Santander, Colombia, la cual pasó de ser un sitio irregular a la próspera Villa de San Carlos del siglo XIX.

  16. Novel Technique for Assessing Ammonium Utilization by Phytoplankton in the San Francisco Bay-Delta Estuary

    Science.gov (United States)

    Schmidt, C. M.; Kendall, C.; Young, M. B.; Kraus, T. E. C.; Silva, S. R.; Richter, M. T.

    2015-12-01

    High concentrations of NH4+ in the San Francisco Bay-Delta Estuary (SFE) have been shown to inhibit the growth of phytoplankton, which are an important food source to zooplankton at the base of the pelagic food web. Here we present results from a study which used a stable isotope mixing model to quantify the proportion of nitrogen assimilated as NH4+ by phytoplankton in situ in a portion of the Sacramento River where NH4+ concentration is elevated downstream of the Sacramento Regional Wastewater Treatment Plant (SRWTP). To determine the δ15N value of phytoplankton, a novel method was developed to isolate phytoplankton from bulk particulate organic matter using flow cytometry prior to isotopic analysis. Modifications were made to an elemental analyzer to allow measurement of the δ15N values of samples containing as little as 0.5 µg N with an analytical precision of 0.2‰ (determined from replicate analysis of standards). During fall and spring field campaigns, two parcels of Sacramento River water (one with wastewater effluent and one without) were tracked and sampled in a Lagrangian sampling scheme over ~80 hours of travel downstream of the SRWTP. Water samples were analyzed for nutrient and chlorophyll concentrations as well δ15N-NO3 and δ15N-NH4+. In addition, approximately ten million phytoplankton cells were sorted from each sample for analysis of δ15N-phytoplankton. In parcels of Sacramento River water without wastewater effluent, NH4+ concentrations remained low and trends in δ15N-phytoplankton followed trends in δ15N-NO3-. In contrast, in the parcels containing SRWTP effluent phytoplankton uptake of N as NH4+ gradually increased from 15% immediately downstream of the SRWTP to as high as 90% after 80 hours of downstream transit. Previous mesocosm incubation experiments have demonstrated depressed growth rates and a rapid switch from NO3- to NH4+ uptake downstream of the SRWTP, suggesting that the apparent gradual increase in the proportion of N

  17. Development, implementation, and validation of a modeling system for the San Francisco Bay and Estuary

    Science.gov (United States)

    Chao, Yi; Farrara, John D.; Zhang, Hongchun; Zhang, Yinglong J.; Ateljevich, Eli; Chai, Fei; Davis, Curtiss O.; Dugdale, Richard; Wilkerson, Frances

    2017-07-01

    A three-dimensional numerical modeling system for the San Francisco Bay is presented. The system is based on an unstructured grid numerical model known as Semi-implicit Cross-scale Hydroscience Integrated System Model (SCHISM). The lateral boundary condition is provided by a regional coastal ocean model. The surface forcing is provided by a regional atmospheric model. The SCHISM results from a decadal hindcast run are compared with available tide gauge data, as well as a collection of temperature and salinity profiles. An examination of the observed climatological annual mean salinities at the United States Geological Survey (USGS) stations shows the highest salinities to be in the open ocean and the lowest well north (upstream) of the Central Bay, a pattern that does not change substantially with season. The corresponding mean SCHISM salinities reproduced the observed variations with location quite well, though with a fresh bias. The lowest values within the Bay occur during spring and the highest values during autumn, mirroring the seasonal variations in river discharge. The corresponding observed mean temperatures within the Bay were 2 to 3° C cooler in the Central Bay than to either the north or south. This observed pattern of a cooler Central Bay was not particularly well reproduced in the SCHISM results, which also showed a cold bias. Examination of the seasonal means revealed that the cool Central Bay pattern is found only during summer in the SCHISM results. The persistent cold and fresh biases in the model control run were nearly eliminated in a sensitivity run with modifications to the surface heat flux and river discharge. The surface atmospheric forcing and the heat flux at the western boundary are found to be the two major terms in a SCHISM-based heat budget analysis of the mean seasonal temperature cycle for the Central Bay. In the Central Bay salt budget, freshwater discharged by rivers into upstream portions of the Bay to the north balanced by the

  18. Phytoplankton in the Upper San Francisco Estuary: Recent Biomass Trends, Their Causes, and Their Trophic Significance

    Directory of Open Access Journals (Sweden)

    Alan Jassby

    2008-02-01

    Full Text Available Several pelagic fish populations in the upper San Francisco Estuary have recently declined to historically low abundances, prompting an interest in the status of their food supply. Previous studies have indicated that the primary food supply for metazoans in the Delta is phytoplankton productivity, and the long-term decrease in phytoplankton over the last few decades may very well play a role in the long-term decline of pelagic fish abundance. Regional phytoplankton biomass trends during 1996–2005, however, are positive in the Delta and neutral in Suisun Bay, the two major sub-regions of the upper estuary. The trend in Delta primary productivity is also positive. Changes in phytoplankton biomass and production during the last decade are therefore unlikely to be the cause of these more recent metazoan declines. The main source of interannual phytoplankton variability in the Delta during 1996–2005, including the upward trend, appears to have been freshwater flow variability and its effect on particle residence time. This conclusion is supported by trend analyses; the concurrence of these time trends at widely-separated stations; empirical models at the annual and monthly time scales; particle residence time estimates; and experience from other estuaries. A significant temperature increase was also noticed, at least partially independent of flow changes, but its net effect on the phytoplankton community is unknown because of differential effects on growth and loss processes. Phytoplankton biomass in Suisun Bay, in contrast to the Delta, did not increase during 1996–2005. Consistent with this observation, Suisun Bay phytoplankton exhibited relatively low responsiveness to flow variability. This behavior differs from earlier chlorophyll-flow relationships reported in the literature. The reason appears to be the invasion of Suisun Bay by a clam—Corbula amurensis—in 1986, which has since maintained the phytoplankton community mostly at low

  19. San Francisco Volcanic Field, Arizona, as AN Analog for Lunar and Martian Surface Exploration

    Science.gov (United States)

    Young, K. E.; Hodges, K.; Eppler, D.; Horz, F.; Lofgren, G. E.; Hurtado, J. M.; Desert Rats Science Team

    2010-12-01

    Terrestrial analog sites are an important tool that planetary geologists and engineers can use to examine both the geologic processes that shape other planetary surfaces as well as to develop and test technologies that are needed for the exploration of planetary surfaces. During the Apollo era, sites like Meteor Crater, Arizona, were used to train astronauts in the protocols and practices of field geology so that their lunar surface activities would be more geologically productive and efficient. As we enter a new period of planetary surface exploration, analogs will be increasingly important in preparing the next generation of both human and robotic planetary explorers. No single analog will be representative of another planetary surface, but testing technologies in a variety of settings will provide NASA and other space agencies with the operational knowledge needed to launch exploratory missions. The site we present here is one of many that can be used to explore surface operations on other planetary surfaces. The San Francisco Volcanic Field (SFVF), containing both SP Crater and Black Point Lava Flow (BPLF), Arizona, is currently being used as the test site for the Desert Research and Technology Studies (D-RATS) field test, coordinated by Johnson Space Center (JSC) and involving several other NASA centers. During the 2010 test, two habitat rovers (Space Exploration Vehicles, or SEVs) operated simultaneously, each with one astronaut crewmember and one geologist crewmember. The mission lasted 14 days and traversed some 150 km. The geologic setting of SFVF includes a series of ~2 Ma basaltic lava flows overlying Triassic sedimentary rocks, both among the predominant rock types that are found primarily on Mars. SFVF has also been identified as an analog to the Marius Hills on the Moon, a Constellation site of interest. In addition, D-RATS 2010 is simulating operational scenarios based on notional traverses near the Malapert Massif on the lunar surface. While SFVF is

  20. The critical role of islands for waterbird breeding and foraging habitat in managed ponds of the South Bay Salt Pond Restoration Project, South San Francisco Bay, California

    Science.gov (United States)

    Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark P.; Smith, Lacy M.; Moskal, Stacy M.; De La Cruz, Susan E. W.; Yee, Julie L.; Takekawa, John Y.

    2014-01-01

    The South Bay Salt Pond Restoration Project aims to restore 50–90 percent of former salt evaporation ponds into tidal marsh in South San Francisco Bay, California. However, large numbers of waterbirds use these ponds annually as nesting and foraging habitat. Islands within ponds are particularly important habitat for nesting, foraging, and roosting waterbirds. To maintain current waterbird populations, the South Bay Salt Pond Restoration Project plans to create new islands within former salt ponds in South San Francisco Bay. In a series of studies, we investigated pond and individual island attributes that are most beneficial to nesting, foraging, and roosting waterbirds.

  1. The integration of engineering and architecture: A perspective on natural ventilation for the new San Francisco Federal Building

    Energy Technology Data Exchange (ETDEWEB)

    McConahey, Erin; Haves, Philip; Christ, Tim

    2002-05-31

    A description of the in-progress design of a new Federal Office Building for San Francisco is used to illustrate a number of issues arising in the design of large, naturally ventilated office buildings. These issues include the need for an integrated approach to design involving the architects, mechanical and structural engineers, lighting designers and specialist simulation modelers. In particular, the use of natural ventilation, and the avoidance of air-conditioning, depends on the high degree of exposed thermal mass made possible by the structural scheme and by the minimization of solar heat gains while maintaining the good daylighting that results from optimization of the fagade. Another issue was the need for a radical change in interior space planning in order to enhance the natural ventilation; all the individual enclosed offices are located along the central spine of each floorplate rather than at the perimeter. The role of integration in deterring the undermining of the design through value engineering is discussed. The comfort criteria for the building were established based on the recent extension to the ASHRAE comfort standard based on the adaptive model for naturally ventilated buildings. The building energy simulation program EnergyPlus was used to compare the performance of different natural ventilation strategies. The results indicate that, in the San Francisco climate, wind-driven ventilation provides sufficient nocturnal cooling to maintain comfortable conditions and that external chimneys do not provide significant additional ventilation at times when it when it would be beneficial.

  2. Gender differences in causes of death among persons with HIV/AIDS in San Francisco, California, 1996-2013.

    Science.gov (United States)

    Hessol, Nancy A; Schwarcz, Sandra K; Hsu, Ling Chin; Shumway, Martha; Machtinger, Edward L

    2017-01-01

    The objective was to examine gender differences in causes of death using the San Francisco HIV/AIDS and death registries. Data from San Francisco residents diagnosed with HIV/AIDS who died from 1996 to 2013 were analyzed. Age, race/ethnicity, year, and gender-adjusted standardized mortality ratios and Poisson 95% confidence intervals were calculated for underlying causes of death. Among the 6268 deaths, deaths attributed to drug use, mental disorders due to substance use, cerebrovascular disease, chronic obstructive pulmonary disease, renal disease, and septicemia were more likely among women than among men. Compared to the California population, women had elevated standardized mortality ratios for drug overdose (25.37), mental disorders due to substance abuse (27.21), cerebrovascular disease (2.83), chronic obstructive pulmonary disease (7.37), heart disease (2.37), and liver disease (5.54), and these were higher than the standardized mortality ratios for the men in our study. Men, but not women, had elevated standardized mortality ratios for suicide (2.70), undetermined intent (3.88), renal disease (2.29), and non-AIDS cancer (1.68) compared to population rates. Continued efforts to reduce HIV-related illnesses and an increased emphasis on diagnosing and treating preventable causes of death, including substance use, heart disease, and mental health disorders, are needed as part of comprehensive HIV care.

  3. Six-year mortality in a street-recruited cohort of homeless youth in San Francisco, California

    Directory of Open Access Journals (Sweden)

    Colette L. Auerswald

    2016-04-01

    Full Text Available Objectives. The mortality rate of a street-recruited homeless youth cohort in the United States has not yet been reported. We examined the six-year mortality rate for a cohort of street youth recruited from San Francisco street venues in 2004. Methods. Using data collected from a longitudinal, venue-based sample of street youth 15–24 years of age, we calculated age, race, and gender-adjusted mortality rates. Results. Of a sample of 218 participants, 11 died from enrollment in 2004 to December 31, 2010. The majority of deaths were due to suicide and/or substance abuse. The death rate was 9.6 deaths per hundred thousand person-years. The age, race and gender-adjusted standardized mortality ratio was 10.6 (95% CI [5.3–18.9]. Gender specific SMRs were 16.1 (95% CI [3.3–47.1] for females and 9.4 (95% CI [4.0–18.4] for males. Conclusions. Street-recruited homeless youth in San Francisco experience a mortality rate in excess of ten times that of the state’s general youth population. Services and programs, particularly housing, mental health and substance abuse interventions, are urgently needed to prevent premature mortality in this vulnerable population.

  4. Impacts of an underwater high voltage DC power cable on fish migration movements in the San Francisco Bay.

    Science.gov (United States)

    Wyman, M. T.; Kavet, R.; Klimley, A. P.

    2016-02-01

    There is an increasingly strong interest on a global scale in offshore renewable energy production and transportation. However, there is concern that the electromagnetic fields (EMF) produced by these underwater cables may alter the behavior and physiology of marine species. Despite this concern, few studies have investigated these effects in free-living species. In 2009, a 85 km long high-voltage DC (HVDC) power cable was placed within the San Francisco Bay, running parallel, then perpendicular to, the migration route of anadromous species moving from the inland river system to the oceans. In this study, we assess the impacts of this HVDC cable on the migration behaviors of EMF-sensitive fish, including juvenile salmonids (Chinook salmon, Oncorhynchus tshawytscha, and steelhead trout, Oncorhynchus mykiss) and adult green sturgeon, Acipenser medirostris. Acoustic telemetry techniques were used to track fish migration movements through the San Francisco Bay both before and after the cable was activated; individuals implanted with acoustic transmitters were detected on cross-channel hydrophone arrays at key locations in the system. Magnetic fields were surveyed and mapped at these locations using a transverse gradiometer, and models of the cable's magnetic field were developed that closely matched the empirically measured values. Here, we present our analyses on the relationships between migration-related behavioral metrics (e.g., percent of successful migrations, duration of migration, time spent near vs. far from cable location, etc.) and environmental parameters, such as cable activation and load level, local magnetic field levels, depth, and currents.

  5. Disease Risk & Landscape Attributes of Tick-Borne Borrelia Pathogens in the San Francisco Bay Area, California.

    Science.gov (United States)

    Salkeld, Daniel J; Nieto, Nathan C; Carbajales-Dale, Patricia; Carbajales-Dale, Michael; Cinkovich, Stephanie S; Lambin, Eric F

    2015-01-01

    Habitat heterogeneity influences pathogen ecology by affecting vector abundance and the reservoir host communities. We investigated spatial patterns of disease risk for two human pathogens in the Borrelia genus-B. burgdorferi and B. miyamotoi-that are transmitted by the western black-legged tick, Ixodes pacificus. We collected ticks (349 nymphs, 273 adults) at 20 sites in the San Francisco Bay Area, California, USA. Tick abundance, pathogen prevalence and density of infected nymphs varied widely across sites and habitat type, though nymphal western black-legged ticks were more frequently found, and were more abundant in coast live oak forest and desert/semi-desert scrub (dominated by California sagebrush) habitats. We observed Borrelia infections in ticks at all sites where we able to collect >10 ticks. The recently recognized human pathogen, B. miyamotoi, was observed at a higher prevalence (13/349 nymphs = 3.7%, 95% CI = 2.0-6.3; 5/273 adults = 1.8%, 95% CI = 0.6-4.2) than recent studies from nearby locations (Alameda County, east of the San Francisco Bay), demonstrating that tick-borne disease risk and ecology can vary substantially at small geographic scales, with consequences for public health and disease diagnosis.

  6. Avian response to early tidal salt marsh restoration at former commercial salt evaporation ponds in San Francisco Bay, California, USA

    Science.gov (United States)

    Athearn, Nicole D.; Takekawa, John Y.; Shinn, Joel

    2009-01-01

    Restoration of former commercial salt evaporation ponds in the San Francisco Bay estuary is intended to reverse a severe decline (>79%) in tidal salt marshes. San Francisco Bay is a critical migratory stopover site and wintering area for shorebirds and waterfowl, and salt ponds are important high tide roosting and foraging areas. Conservation of past bird abundance is a stated goal of area restoration projects, and early adaptive management will be critical for achieving this objective. However, initial avian response at sites restored to tidal flow may not be indicative of long-term results. For example, winter shorebirds at a 529 ha pond breached in 2002 showed a marked increase in shorebird abundance following breaching. Shorebirds comprised 1% of area totals during 1999-2002 and increased to 46% during 2003-2008. These changes accompanied increased tidal range and sedimentation, but minimal vegetation establishment. Conversely, a fully vegetated, restored 216 ha pond in the same system consistently supported less than 2% of all waterbirds in the region. Early restoration may temporarily increase habitat, but managed ponds will be needed for long-term waterbird abundance within a restored pond-marsh system.

  7. Who uses needle exchange? A study of injection drug users in treatment in San Francisco, 1989-1990.

    Science.gov (United States)

    Hahn, J A; Vranizan, K M; Moss, A R

    1997-06-01

    We examined use of the San Francisco needle exchange program (NEP) by 1093 injection drug users (IDUs) recruited in methadone maintenance and out-patient detoxification programs in the first 2 years after the opening of the NEP in 1988. Thirty-one percent of IDUs had ever used the NEP. IDUs who were frequent injectors, homeless, and aware of their serostatus were more likely to use the NEP. To assess self-selection of IDUs at risk for seroconversion for using needle exchange, we calculated pre-needle exchange seroconversion rates. Among 385 IDUs seen twice, the HIV seroconversion rate was 0.38% per person year among subjects who never used needle exchange, but it was 9.34% per person year among those who later used needle exchange (p = 0.003). NEP attracted a subset of IDUs at very high risk for HIV infection. Among injectors who were interviewed before and after the opening of the needle exchanges in San Francisco, the number of sharing partners did not change among IDUs who attended or among IDUs who never attended the NEP. The NEP attracted a very-high-risk subgroup of IDUs, as measured by risk behavior and pre-needle exchange HIV-seroconversion rate. NEPs should be considered prime sites for behavior-change interventions.

  8. San Francisco Bay-Delta bathymetric/topographic digital elevation model (DEM)

    Science.gov (United States)

    Fregoso, Theresa; Wang, Rueen-Fang; Ateljevich, Eli; Jaffe, Bruce E.

    2017-01-01

    bathymetry data collected by the COE and USGS scientists, expanding the DEM to include the northernmost areas of the Sacramento-San Joaquin Delta, and by making use of a two-meter seamless bathymetric/topographic DEM from the USGS EROS Data Center (2013) of the San Francisco Bay region.The resulting 10-meter USGS DEM encompasses the entirety of Suisun Bay, beginning with the Carquinez Strait in the west, east to California Interstate 5, north following the path of the Yolo Bypass and the Sacramento River up to Knights Landing, and the American River northeast to the Nimbus Dam, and south to areas around Tracy. The DEM incorporates the newest available bathymetry data at the time of release, as well as including, at minimum, a 100-meter band of available topography data adjacent to most shorelines. No data areas within the DEM are areas where no elevation data exists, either due to a gap in the land/water interface, or because lidar was collected over standing water that was then cut out of the DEM.Environmental Systems Research Institute, Inc., 2015, Topo to Raster:  http://desktop.arcgis.com/en/desktop/latest/tools/3d-analyst-toolbox/topo-to-raster.htmFoxgrover, A., Smith, R.E., and Jaffe, B.E., 2005, Suisun Bay and Delta Bathymetry: http://sfbay.wr.usgs.gov/sediment/delta/index.htmlUSGS EROS Data Center, 2013, 2 m Coastal National Elevation Dataset: http://topotools.cr.usgs.gov/topobathy_viewer/Wang, R-F., and Ateljevich, E., 2012, A continuous surface elevation map for modeling, chapter 6 in California Department of Water Resources, Methodology for flow and salinity estimates in the Sacramento-San Joaquin Delta and Suisun Marsh, 33rd Annual Progress Report to the StateWater Resources Control Board:  California Department of Water Resources, Bay-Delta Office, Delta Modeling Section, http://baydeltaoffice.water.ca.gov/modeling/deltamodeling/AR2012/Chapter%206_2012_Web.pdf

  9. Modeling Magnetic Fields from a DC Power Cable Buried Beneath San Francisco Bay Based on Empirical Measurements.

    Science.gov (United States)

    Kavet, Robert; Wyman, Megan T; Klimley, A Peter

    2016-01-01

    The Trans Bay Cable (TBC) is a ±200-kilovolt (kV), 400 MW 85-km long High Voltage Direct Current (DC) buried transmission line linking Pittsburg, CA with San Francisco, CA (SF) beneath the San Francisco Estuary. The TBC runs parallel to the migratory route of various marine species, including green sturgeon, Chinook salmon, and steelhead trout. In July and August 2014, an extensive series of magnetic field measurements were taken using a pair of submerged Geometrics magnetometers towed behind a survey vessel in four locations in the San Francisco estuary along profiles that cross the cable's path; these included the San Francisco-Oakland Bay Bridge (BB), the Richmond-San Rafael Bridge (RSR), the Benicia-Martinez Bridge (Ben) and an area in San Pablo Bay (SP) in which a bridge is not present. In this paper, we apply basic formulas that ideally describe the magnetic field from a DC cable summed vectorially with the background geomagnetic field (in the absence of other sources that would perturb the ambient field) to derive characteristics of the cable that are otherwise not immediately observable. Magnetic field profiles from measurements taken along 170 survey lines were inspected visually for evidence of a distinct pattern representing the presence of the cable. Many profiles were dominated by field distortions unrelated to the cable caused by bridge structures or other submerged objects, and the cable's contribution to the field was not detectable. BB, with 40 of the survey lines, did not yield usable data for these reasons. The unrelated anomalies could be up to 100 times greater than those from the cable. In total, discernible magnetic field profiles measured from 76 survey lines were regressed against the equations, representing eight days of measurement. The modeled field anomalies due to the cable (the difference between the maximum and minimum field along the survey line at the cable crossing) were virtually identical to the measured values. The modeling

  10. Modeling Magnetic Fields from a DC Power Cable Buried Beneath San Francisco Bay Based on Empirical Measurements.

    Directory of Open Access Journals (Sweden)

    Robert Kavet

    Full Text Available The Trans Bay Cable (TBC is a ±200-kilovolt (kV, 400 MW 85-km long High Voltage Direct Current (DC buried transmission line linking Pittsburg, CA with San Francisco, CA (SF beneath the San Francisco Estuary. The TBC runs parallel to the migratory route of various marine species, including green sturgeon, Chinook salmon, and steelhead trout. In July and August 2014, an extensive series of magnetic field measurements were taken using a pair of submerged Geometrics magnetometers towed behind a survey vessel in four locations in the San Francisco estuary along profiles that cross the cable's path; these included the San Francisco-Oakland Bay Bridge (BB, the Richmond-San Rafael Bridge (RSR, the Benicia-Martinez Bridge (Ben and an area in San Pablo Bay (SP in which a bridge is not present. In this paper, we apply basic formulas that ideally describe the magnetic field from a DC cable summed vectorially with the background geomagnetic field (in the absence of other sources that would perturb the ambient field to derive characteristics of the cable that are otherwise not immediately observable. Magnetic field profiles from measurements taken along 170 survey lines were inspected visually for evidence of a distinct pattern representing the presence of the cable. Many profiles were dominated by field distortions unrelated to the cable caused by bridge structures or other submerged objects, and the cable's contribution to the field was not detectable. BB, with 40 of the survey lines, did not yield usable data for these reasons. The unrelated anomalies could be up to 100 times greater than those from the cable. In total, discernible magnetic field profiles measured from 76 survey lines were regressed against the equations, representing eight days of measurement. The modeled field anomalies due to the cable (the difference between the maximum and minimum field along the survey line at the cable crossing were virtually identical to the measured values. The

  11. Greenhouse Gas (GHG) Source Detection and Attribution in the San Francisco Bay Area of California Using a Mobile Measurement Platform

    Science.gov (United States)

    Guha, A.; Bower, J.; Martien, P. T.; Perkins, I.; Randall, S.; Stevenson, E.; Young, A.; Hilken, H.

    2016-12-01

    The Bay Area Air Quality Management District is the greater San Francisco Bay metropolitan area's chief air quality regulatory agency. Aligning itself with the Governor's Executive Order S-3-05, the Air District has set a goal to reduce the region's GHG emissions by 80% below 1990 levels by the year 2050. The Air District's 2016 Clean Air Plan will lay out the agency's vision and actions to put the region on a path forward towards achieving the 2050 goal while also reducing air pollution and related health impacts. The 2016 Plan has three overarching objectives: 1) develop a multi-pollutant emissions control strategy, (2) reduce population exposure to harmful air pollutants, especially in vulnerable communities, and (3) protect climate through a comprehensive Regional Climate Protection Strategy. To accomplish one of 2016 Plan's control measures (SL3 - Greenhouse Gas Monitoring and Measurement Network), the Air District has fabricated a mobile measurement platform i.e. a GHG research van to perform targeted CH4 emissions hotspot detection and source attribution. The van is equipped with analyzers capable of measuring CH4, CO2 and N2O in ambient plumes at fast sampling rates. The coincident measurement of source tracers like isotopic methane (13C - CH4), CO and ethane (C2H6) provide the capability to distinguish between biogenic, combustion-based and fossil-based fugitive methane sources, respectively. The GHG research van is a comprehensive mobile tool to perform tracer-based GHG source identification and apportionment. We report observation-based source-specific tracer-to-tracer emission ratios from a region-wide survey of well-known area sources like landfills, wastewater treatment facilities and dairies, and compare those with similar ratios in the Air District's GHG inventory. We also investigate plumes from potentially under-inventoried sources like anaerobic digesters, composting operations, active and plugged oil and gas wells, and a natural gas storage

  12. Reducing methylmercury accumulation in the food webs of San Francisco Bay and its local watersheds

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J.A., E-mail: jay@sfei.org [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Looker, R.E. [San Francisco Bay Regional Water Quality Control Board, 1515 Clay Street, Suite 1400, Oakland, CA 94612 (United States); Yee, D. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Marvin-Di Pasquale, M. [U.S. Geological Survey, Water Resources Division/MS 480, 345 Middlefield Road, Menlo Park, CA 94025 (United States); Grenier, J.L. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Austin, C.M. [San Francisco Bay Regional Water Quality Control Board, 1515 Clay Street, Suite 1400, Oakland, CA 94612 (United States); McKee, L.J.; Greenfield, B.K. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Brodberg, R. [California Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, 1001 I Street, Sacramento, CA 95812 (United States); Blum, J.D. [Department of Geological Sciences, University of Michigan, 1100 North University Avenue, Ann Arbor, MI 48109 (United States)

    2012-11-15

    San Francisco Bay (California, USA) and its local watersheds present an interesting case study in estuarine mercury (Hg) contamination. This review focuses on the most promising avenues for attempting to reduce methylmercury (MeHg) contamination in Bay Area aquatic food webs and identifying the scientific information that is most urgently needed to support these efforts. Concern for human exposure to MeHg in the region has led to advisories for consumption of sport fish. Striped bass from the Bay have the highest average Hg concentration measured for this species in USA estuaries, and this degree of contamination has been constant for the past 40 years. Similarly, largemouth bass in some Bay Area reservoirs have some of the highest Hg concentrations observed in the entire US. Bay Area wildlife, particularly birds, face potential impacts to reproduction based on Hg concentrations in the tissues of several Bay species. Source control of Hg is one of the primary possible approaches for reducing MeHg accumulation in Bay Area aquatic food webs. Recent findings (particularly Hg isotope measurements) indicate that the decades-long residence time of particle-associated Hg in the Bay is sufficient to allow significant conversion of even the insoluble forms of Hg into MeHg. Past inputs have been thoroughly mixed throughout this shallow and dynamic estuary. The large pool of Hg already present in the ecosystem dominates the fraction converted to MeHg and accumulating in the food web. Consequently, decreasing external Hg inputs can be expected to reduce MeHg in the food web, but it will likely take many decades to centuries before those reductions are achieved. Extensive efforts to reduce loads from the largest Hg mining source (the historic New Almaden mining district) are underway. Hg is spread widely across the urban landscape, but there are a number of key sources, source areas, and pathways that provide opportunities to capture larger quantities of Hg and reduce loads

  13. Handbook of Techniques and Guides for the Study of the San Francisco Bay-Delta-Estuary Complex, Part 3. Key to the Invertebrates.

    Science.gov (United States)

    Shettler, James

    Project MER (Marine Ecology Research) is aimed at improving environmental education in the San Francisco Bay Area schools. As part of meeting this goal, it is hoped that students and teachers can see the results of their efforts being put to practical use. This guide is the third of a series produced to help students and teachers gather data…

  14. Muusikamaailm : Brüsseli La Monnaie ئ 300. Uusooper San Franciscos. Sibeliuse nädal esiettekannetega. Cesare Valletti surnud / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2000-01-01

    Brüsseli teater Theatre Royal de la Monnaie sai linnalt 300. juubeli kingituseks lisaruume, hooaja ooperiesiettekannetest teatris. J. Heggie ooperi "Dead man walking" maailmaesiettekandest San Francisco Ooperis. 30.sept.-8. okt. toimunud Sibeliuse nädalast Järvenpää-talos. Lühidalt C. Vallettist

  15. Creep and drying shrinkage of high performance concrete for the skyway structures of the new San Francisco-Oakland Bay Bridge and cement paste

    Science.gov (United States)

    2011-03-01

    The objective of this study was to determine the influence of admixtures on long term drying shrinkage and creep of high : strength concrete (HSC). Creep and shrinkage of the mix utilized in segments of the Skyway Structure of the San : Francisco-Oak...

  16. Foreign Language Folio. A Guide to Cultural Resources and Field Trip Opportunities in the San Francisco Bay Area for Teachers and Students of Foreign Languages, 1983-85.

    Science.gov (United States)

    Gonzales, Tony, Ed.; O'Connor, Roger, Ed.

    A listing of San Francisco area cultural resources and opportunities of use to foreign language teachers is presented. Included are the following: museums and galleries, schools, art sources, churches, clubs, cultural centers and organizations, publications and publishing companies, restaurants, food stores and markets, travel and tourism,…

  17. The Female/Male Salary Differential in Public Schools: Some Lessons from San Francisco, 1879. Program Report No. 79-B7.

    Science.gov (United States)

    Strober, Myra H.; Best, Laura

    This paper develops a theory of sex differences in the earnings of school personnel, with emphasis on the role of labor market segmentation. Several aspects of the theory are then tested using data for the San Francisco school system in 1879. Section 1 develops a theory of sex differences in the earnings of school personnel. Section 2 discusses…

  18. Co-Production of Actionable Science: Recommendations to the Secretary of Interior and a San Francisco Case Study

    Science.gov (United States)

    Behar, D. H.; Pfeffer, W. T.; Beier, P.

    2015-12-01

    "Actionable Science provides data, analyses, projections, or tools that can support decisions regarding the management of the risks and impacts of climate change. It is ideally co-produced by scientists and decision makers and creates rigorous and accessible products to meet the needs of stakeholders. (Report to the Secretary of the Interior, Advisory Committee on Climate Change and Natural Resource Science (ACCCNRS), March 30, 2015)During one 17 month period ending in 2013, three major reports on sea level rise from three highly respected science providers produced three divergent estimates of sea level rise. These reports collectively flummoxed the lay reader seeking direction for adaptation planning. Guidance documents soon emerged from state entities which caused further confusion. The City and County of San Francisco began developing "Guidance for Incorporating Sea Level Rise into Capital Planning" in 2013 at the direction of San Francisco Mayor Edwin Lee (http://onesanfrancisco.org/staff-resources/sea-level-rise-guidance/). The first task in developing this Guidance was to convert these highly technical reports into "actionable science." This required extensive expert elicitation to tease out their meaning and use value for decision making. This process, which resulted in detailed guidance on the use of SLR science in planning, is increasingly being called "co-production."Co-production requires both scientist and decision-maker to hear the other's perspective, reflect upon the decision-maker's precise needs, and translate peer review science into lay language and practical advice for decision making. The co-production dynamic was the subject of extensive discussion in the federal Advisory Committee on Climate Change and Natural Resource Science. The ACCCNRS recommendations (https://nccwsc.usgs.gov/acccnrs) include not only the new definition of Actionable Science cited above, but also a "How-To-Guide" that outlines principles for successfully creating a co

  19. A Novel Modeling Approach for Estimating Patterns of Migration into and out of San Francisco by HIV Status and Race among Men Who Have Sex with Men.

    Science.gov (United States)

    Hughes, Alison J; Chen, Yea-Hung; Scheer, Susan; Raymond, H Fisher

    2017-06-01

    In the early 1980s, men who have sex with men (MSM) in San Francisco were one of the first populations to be affected by the human immunodeficiency virus (HIV) epidemic, and they continue to bear a heavy HIV burden. Once a rapidly fatal disease, survival with HIV improved drastically following the introduction of combination antiretroviral therapy in 1996. As a result, the ability of HIV-positive persons to move into and out of San Francisco has increased due to lengthened survival. Although there is a high level of migration among the general US population and among HIV-positive persons in San Francisco, in- and out-migration patterns of MSM in San Francisco have, to our knowledge, never been described. Understanding migration patterns by HIV serostatus is crucial in determining how migration could influence both HIV transmission dynamics and estimates of the HIV prevalence and incidence. In this article, we describe methods, results, and implications of a novel approach for indirect estimation of in- and out-migration patterns, and consequently population size, of MSM by HIV serostatus and race in San Francisco. The results suggest that the overall MSM population and all the MSM subpopulations studied decreased in size from 2006 to 2014. Further, there were differences in migration patterns by race and by HIV serostatus. The modeling methods outlined can be applied by others to determine how migration patterns contribute to HIV-positive population size and output from these models can be used in a transmission model to better understand how migration can impact HIV transmission.

  20. Incidental catch and mortality of striped bass, Morone saxatilis, in the commercial bay shrimp trawl fishery in the San Francisco estuarine complex

    OpenAIRE

    Reilly, Paul N.

    1991-01-01

    The commercial bay shrimp fishery was monitored from April 1989 to September 1990 in south San Francisco Bay, and from September 1989 to September 1990 in San Pablo Bay and Carquinez Strait, to estimate incidental catch and mortality of young-of-the-year (YOY), juvenile and adult striped bass. Of the total estimated by-catch of 44,000 to 52,000 YOY bass, 98.5% were taken in San Pablo Bay. Of the total estimated bycatch of 3160 to 3570 older bass, approximately 75% w...

  1. Water quality measurements in San Francisco Bay by the U.S. Geological Survey, 1969–2015

    Science.gov (United States)

    Schraga, Tara; Cloern, James E.

    2017-01-01

    The U.S. Geological Survey (USGS) maintains a place-based research program in San Francisco Bay (USA) that began in 1969 and continues, providing one of the longest records of water-quality measurements in a North American estuary. Constituents include salinity, temperature, light extinction coefficient, and concentrations of chlorophyll-a, dissolved oxygen, suspended particulate matter, nitrate, nitrite, ammonium, silicate, and phosphate. We describe the sampling program, analytical methods, structure of the data record, and how to access all measurements made from 1969 through 2015. We provide a summary of how these data have been used by USGS and other researchers to deepen understanding of how estuaries are structured and function differently from the river and ocean ecosystems they bridge.

  2. Alice Gaillard, Les Diggers. Révolution et contre-culture à San Francisco (1966-1968)

    OpenAIRE

    Ferrand, Laure

    2014-01-01

    Les Diggers sont un groupe apparu à San Francisco en 1966. Avec leur théâtre de rue, leurs tracts et leurs performances, ils s’approprient le petit quartier de Haight Ashbury. Le contexte est au phénomène hippie, à la contestation contre la guerre du Vietnam, à l’émergence du Free Speech Movement, qui a émergé à l’automne 1964 sur le campus de l’université de Berkeley, et au « psychédélisme » : en 1963, Timothy Leary, jeune docteur en psychologie clinique, écrit dans la Harvard Review un text...

  3. User's guide to the LIRAQ model: an air pollution model for the San Francisco Bay Area

    Energy Technology Data Exchange (ETDEWEB)

    MacCracken, M.C.

    1975-12-19

    The Livermore Regional Air Quality (LIRAQ) model comprises a set of computer programs that have been integrated into an easily used tool for the air quality planner. To assemble and modify the necessary data files and to direct model execution, a problem formulation program has been developed that makes possible the setup of a wide variety of studies involving perturbation of the emission inventory, changes to the initial and boundary conditions, and different choices of grid size and problem domain. In addition to describing the types of air quality problems for which the LIRAQ model may be used, this User's Guide provides detailed information on how to set up and conduct model simulations. Also included are descriptions of the formats of input data files so that the LIRAQ model may be applied to regions other than the San Francisco Bay Area.

  4. Pollutant body burdens and reproduction in Platichthys stellatus from San Francisco Bay. Annual progress report, year I

    Energy Technology Data Exchange (ETDEWEB)

    Spies, R.; Rice, D.; Ireland, R.; Beach, J.

    1983-08-01

    The effects of sublethal levels of pollutants in the tissues of estuarine fish on reproductive success were determined. The relationships among several measures of reproductive success (percent fertilization, hatching success, abnormal larvae) and biochemical measures of pollutant exposure (induced mixed-function oxidase) as well as direct measures of chemical pollutants in tissues were examined. Populations were sampled during active gametogenesis and during the spawning season. Tissues have been preserved for pollutant analyses. The reproductive success of captured spawning females was evaluated, and mixed-function oxidase (MFO) activity measured in captured fish. The results indicate the reproductive success of starry flounder in San Francisco Bay is being impaired by organic pollutants. 14 references, 8 figures, 11 tables.

  5. Building leadership among laboratory-based and clinical and translational researchers: the University of California, San Francisco experience.

    Science.gov (United States)

    Wides, Cynthia; Mertz, Elizabeth; Lindstaedt, Bill; Brown, Jeanette

    2014-02-01

    In 2005 the University of California, San Francisco (UCSF) implemented the Scientific Leadership and Management (SLM) course, a 2-day leadership training program to assist laboratory-based postdoctoral scholars in their transition to independent researchers managing their own research programs. In 2011, the course was expanded to clinical and translational junior faculty and fellows. The course enrollment was increased from approximate 100 to 123 participants at the same time. Based on course evaluations, the number and percent of women participants appears to have increased over time from 40% (n = 33) in 2007 to 53% (n = 58) in 2011. Course evaluations also indicated that participants found the course to be relevant and valuable in their transition to academic leadership. This paper describes the background, structure, and content of the SLM and reports on participant evaluations of the course offerings from 2007 through 2011. © 2014 Wiley Periodicals, Inc.

  6. National Account Energy Alliance Final Report for the Ritz Carlton, San Francisco Combined Heat and Power Project

    Energy Technology Data Exchange (ETDEWEB)

    Rosfjord, Thomas J [UTC Power

    2007-11-01

    Under collaboration between DOE and the Gas Technology Institute (GTI), UTC Power partnered with Host Hotels and Resorts to install and operate a PureComfort 240M Cooling, Heating and Power (CHP) System at the Ritz-Carlton, San Francisco. This packaged CHP system integrated four microturbines, a double-effect absorption chiller, two fuel gas boosters, and the control hardware and software to ensure that the system operated predictably, reliably, and safely. The chiller, directly energized by the recycled hot exhaust from the microturbines, could be configured to provide either chilled or hot water. As installed, the system was capable of providing up to 227 kW of net electrical power and 142 RT of chilled water at a 59F ambient temperature.

  7. Feasibility of providing interventions for injection drug users in pharmacy settings: a case study among San Francisco pharmacists.

    Science.gov (United States)

    Rose, Valerie J; Lutnick, Alexandra; Kral, Alex H

    2014-01-01

    In addition to syringe exchange programs, pharmacies are important venues where injection drug users (IDUs) can access non-prescription syringes and other prevention interventions. This study assessed the feasibility of providing a range of interventions for IDUs in pharmacy settings. Semi-structured qualitative interviews were conducted with 23 participants (policy makers, owner/managers, dispensing pharmacists, and pharmacy staff) from independent and chain/retail pharmacies in San Francisco, California, USA. The highest level of support was for a coupon syringe program and educational materials. Several overarching themes illustrate challenges to implementing pharmacy-based preventive interventions: time, space, sufficient staff, pharmacist training, legal considerations, pharmacist attitudes toward IDUs, and cost and reimbursement issues. This study provides concrete examples of the types of preventive services that pharmacists support and consider feasible, and illustrates that pharmacists welcome the opportunity to broaden their role as critical partners in public health matters related to injection drug use.

  8. Susceptibility of seagrass to oil spills: A case study with eelgrass, Zostera marina in San Francisco Bay, USA.

    Science.gov (United States)

    Fonseca, Mark; Piniak, Gregory A; Cosentino-Manning, Natalie

    2017-02-15

    Existing literature illustrates inconsistent responses of seagrasses to oil exposure, both in the field and in the laboratory. Here, we add a new study that combined morphometric, demographic and photophysiology assessments to determine the potential oiling impacts to eelgrass (Zostera marina) from the 2007 Cosco Busan event in San Francisco Bay. Shoot densities, reproductive status, and rhizome elongation of Z. marina were examined at sites with pre-spill data, and eelgrass photosynthetic efficiency was measured post-spill. Shoot densities and percent elongation of rhizome internodes formed after the oil spill varied but with no consistent relationship to adjacent shoreline cleanup assessment team (SCAT) oiling categories. Similarly, differences in seagrass photosynthetic efficiency were not consistent with SCAT oiling categories. While thresholds for negative impacts on seagrass in general remain to be defined, conclusive oiling indicators for degree and duration of exposure would be important considerations and need examination under controlled study. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Social marketing and diffusion-based strategies for communicating with unique populations: HIV prevention in San Francisco.

    Science.gov (United States)

    Dearing, J W; Rogers, E M; Meyer, G; Casey, M K; Rao, N; Campo, S; Henderson, G M

    1996-01-01

    We conducted a 2-year investigation of the extent to which strategies based on social marketing and diffusion of innovations concepts are used in preventive health communication with unique (highly ostracized) populations. Of the 49 organizations in San Francisco that operate HIV prevention programs (N = 100), programs that most highly targeted unique populations were surveyed. Personal interviews were then conducted with 38 staff leaders who operated the most and least effective programs. Audiotapes and transcripts were content analyzed to identify the strategies used by program staff. Strategies based on social marketing concepts were more prevalent than strategies based on the diffusion of innovations: More effective programs were characterized by emphasis on homophily, audience segmentation, compatibility-based strategies, and interorganizational collaboration.

  10. Remote sensing analysis of water quality and the entrapment zone in the San Francisco Bay and delta

    Science.gov (United States)

    Colwell, R. N.; Knight, A. W. (Principal Investigator); Khorram, S.

    1979-01-01

    The author has identified the following significant results. Data from an ocean color scanner flown on a U-2 aircraft at 65,000 ft and from LANDSAT MSS were enhanced to identify biologically active areas of San Francisco Bay, and to determine the salinity, turbidity, chlorophylls, and suspended solids. The best fit regression models for mapping water quality parameters were based on bands 3, 5, 7, and 10. Comparision of the results indicate that chlorophyll concentrations can best be estimated by the OCS or MSS data. Salinity can best be estimated by OCS data; turbidity can best be estimated by LANDSAT data. Neither OCS nor MSS data provide reliable basis for estimating suspended solids. Aerial photography of the highest quality taken with either conventional color or infrared-sensitive color films was unable to locate the biologically active areas.

  11. Water quality measurements in San Francisco Bay by the U.S. Geological Survey, 1969-2015.

    Science.gov (United States)

    Schraga, Tara S; Cloern, James E

    2017-08-08

    The U.S. Geological Survey (USGS) maintains a place-based research program in San Francisco Bay (USA) that began in 1969 and continues, providing one of the longest records of water-quality measurements in a North American estuary. Constituents include salinity, temperature, light extinction coefficient, and concentrations of chlorophyll-a, dissolved oxygen, suspended particulate matter, nitrate, nitrite, ammonium, silicate, and phosphate. We describe the sampling program, analytical methods, structure of the data record, and how to access all measurements made from 1969 through 2015. We provide a summary of how these data have been used by USGS and other researchers to deepen understanding of how estuaries are structured and function differently from the river and ocean ecosystems they bridge.

  12. Quantifying Beach Response to Episodic Large Wave Events, a Predictive Empirical Model, Ocean Beach, San Francisco, CA

    Science.gov (United States)

    Hansen, J. E.; Barnard, P. L.

    2006-12-01

    Predicting beach response on an event scale is extremely difficult due to highly variable spatial and temporal conditions, lack of data on antecedent beach morphology, generic model shortcomings, and uncertainty of local forcing parameters. Each beach system is unique and classical beach erosion models may not be applicable to many high-energy beaches, especially those receiving large long-period waves. Therefore, developing an empirical model is the best way to predict future beach response at a given site. Based on 12 closely spaced (temporally) GPS topographic surveys during the winter of 2005-2006 at Ocean Beach, in San Francisco, California, we have developed a predictive empirical model that relates sub-aerial beach response to observed wave height, period, and direction. The model will provide important information to coastal managers, who will be able to better predict and mitigate possible loss from a forecasted wave event. Ocean Beach, located immediately south of the Golden Gate in San Francisco, is a high-energy, intermediate- slope beach that is exposed to waves generated in both the North and South Pacific. Winter breaking wave heights frequently reach 4 m and can exceed 7 m, with periods sometimes greater than 20 s. Our observations demonstrate that large seasonal variations in the sub-aerial beach profile are likely forced by several single large wave events. These events have led to the partial destruction of a recreational parking lot at the south end of the beach where an erosion hot spot is currently located, and continued erosion will threaten other parts of public infrastructure. This study, in combination with other ongoing research at Ocean Beach, will provide valuable insight that will not only aid local personnel in their management decisions but also contribute to a better understanding of sediment transport at high-energy beaches.

  13. Adapting an ambient monitoring program to the challenge of managing emerging pollutants in the San Francisco Estuary.

    Science.gov (United States)

    Hoenicke, Rainer; Oros, Daniel R; Oram, John J; Taberski, Karen M

    2007-09-01

    While over seven million organic and inorganic compounds that have been indexed by the American Chemical Society's Chemical Abstracts Service in their CAS Registry are commercially available, most pollution monitoring programs focus only on those chemical stressors for which regulatory benchmarks exist, and have been traditionally considered responsible for the most significant human and environmental health risks. Until the late 1990s, the San Francisco Estuary Regional Monitoring Program was no exception in that regard. After a thorough external review, the monitoring program responded to the need for developing a pro-active surveillance approach for emerging pollutants in recognition of the fact that the potential for the growing list of widely used chemical compounds to alter the integrity of water is high. We describe (1) the scientific and analytical bases underlying a new surveillance monitoring approach; (2) summarize approaches used and results obtained from a forensic retrospective; (3) present the growing data set on emerging pollutants from surveillance monitoring and related efforts in the San Francisco Bay Area to characterize newly targeted compounds in wastewater streams, sediment, storm water runoff, and biota; and (4) suggest next steps in monitoring program development and applied research that could move beyond traditional approaches of pollutant characterization. Based on the forensic analysis of archived chromatograms and chemical and toxicological properties of candidate compounds, we quantified a variety of synthetic organic compounds which had previously not been targeted for analysis. Flame retardant compounds, pesticides and insecticide synergists, insect repellents, pharmaceuticals, personal care product ingredients, plasticizers, non-ionic surfactants, and other manufacturing ingredients were detected in water, sediment, and/or biological tissue samples. Several of these compounds, especially polybrominated diphenyl ether flame

  14. Impacts of representing sea-level rise uncertainty on future flood risks: An example from San Francisco Bay.

    Directory of Open Access Journals (Sweden)

    Kelsey L Ruckert

    Full Text Available Rising sea levels increase the probability of future coastal flooding. Many decision-makers use risk analyses to inform the design of sea-level rise (SLR adaptation strategies. These analyses are often silent on potentially relevant uncertainties. For example, some previous risk analyses use the expected, best, or large quantile (i.e., 90% estimate of future SLR. Here, we use a case study to quantify and illustrate how neglecting SLR uncertainties can bias risk projections. Specifically, we focus on the future 100-yr (1% annual exceedance probability coastal flood height (storm surge including SLR in the year 2100 in the San Francisco Bay area. We find that accounting for uncertainty in future SLR increases the return level (the height associated with a probability of occurrence by half a meter from roughly 2.2 to 2.7 m, compared to using the mean sea-level projection. Accounting for this uncertainty also changes the shape of the relationship between the return period (the inverse probability that an event of interest will occur and the return level. For instance, incorporating uncertainties shortens the return period associated with the 2.2 m return level from a 100-yr to roughly a 7-yr return period (∼15% probability. Additionally, accounting for this uncertainty doubles the area at risk of flooding (the area to be flooded under a certain height; e.g., the 100-yr flood height in San Francisco. These results indicate that the method of accounting for future SLR can have considerable impacts on the design of flood risk management strategies.

  15. Impacts of representing sea-level rise uncertainty on future flood risks: An example from San Francisco Bay.

    Science.gov (United States)

    Ruckert, Kelsey L; Oddo, Perry C; Keller, Klaus

    2017-01-01

    Rising sea levels increase the probability of future coastal flooding. Many decision-makers use risk analyses to inform the design of sea-level rise (SLR) adaptation strategies. These analyses are often silent on potentially relevant uncertainties. For example, some previous risk analyses use the expected, best, or large quantile (i.e., 90%) estimate of future SLR. Here, we use a case study to quantify and illustrate how neglecting SLR uncertainties can bias risk projections. Specifically, we focus on the future 100-yr (1% annual exceedance probability) coastal flood height (storm surge including SLR) in the year 2100 in the San Francisco Bay area. We find that accounting for uncertainty in future SLR increases the return level (the height associated with a probability of occurrence) by half a meter from roughly 2.2 to 2.7 m, compared to using the mean sea-level projection. Accounting for this uncertainty also changes the shape of the relationship between the return period (the inverse probability that an event of interest will occur) and the return level. For instance, incorporating uncertainties shortens the return period associated with the 2.2 m return level from a 100-yr to roughly a 7-yr return period (∼15% probability). Additionally, accounting for this uncertainty doubles the area at risk of flooding (the area to be flooded under a certain height; e.g., the 100-yr flood height) in San Francisco. These results indicate that the method of accounting for future SLR can have considerable impacts on the design of flood risk management strategies.

  16. Healthcare Access and PrEP Continuation in San Francisco and Miami After the US PrEP Demo Project.

    Science.gov (United States)

    Doblecki-Lewis, Susanne; Liu, Albert; Feaster, Daniel; Cohen, Stephanie E; Cardenas, Gabriel; Bacon, Oliver; Andrew, Erin; Kolber, Michael A

    2017-04-15

    Pre-exposure prophylaxis (PrEP) for prevention of HIV infection has demonstrated efficacy in randomized controlled trials and in demonstration projects. For PrEP implementation to result in significant reductions in HIV incidence for men who have sex with men in the United States, sufficient access to PrEP care and continued engagement outside of demonstration projects is required. We report the results of a follow-up survey of 173 former participants from the Miami and San Francisco sites of the US PrEP Demo Project, administered 4-6 months after study completion. Survey respondents continued to frequently access medical care and had a high incidence of sexually transmitted infections after completion of the Demo Project, indicating ongoing sexual risk behavior. Interest in continuing PrEP was high with 70.8% indicating that they were "very interested" in continuing PrEP. Among respondents, 39.9% reported continuation of PrEP after completion of the Demo Project, largely through their primary care providers and frequently at low or no cost. Variability in access and engagement was seen, with participants from the San Francisco site, those with medical insurance, and those with a primary care provider at the end of the Demo Project more likely to successfully obtain PrEP medication. Two respondents reported HIV seroconversion in the period between study completion and the follow-up survey. Additional effort to increase equitable access to PrEP outside of demonstration projects is needed to realize the potential impact of this evidence-based prevention intervention.

  17. Franciscanos en la Castilla Bajomedieval : el Monasterio de San Francisco el Viejo de Talavera de la Reina (Toledo

    Directory of Open Access Journals (Sweden)

    César Pacheco Jiménez

    1997-01-01

    Full Text Available En este estudio hacemos una aproximación a la primera implantación de franciscanos en Talavera de la Reina, a través del monasterio de San Francisco el Viejo, uno de los muchos centros de la orden de menores en la Castilla bajomedieval. El convento se mantiene desde mediados del siglo xiii hasta 1494, fecha en la que se funda una nueva casa franciscana bajo la Observancia. Analizamos el marco espacial en donde se asientan los frailes y su incidencia en el panorama religioso y civil, así como las implicaciones que el monasterio debió de tener en la vida política del concejo. En definitiva, un primer acercamiento al problema del franciscanismo local en una etapa de expansión y consolidación de la villa.This study is an approach to the first settiement of franciscans in Talavera de la Reina, in the monastery of San Francisco el Viejo, one among many others centres of the order of minors, during the castilian low middieages. This convent is open from the middie of the XIII century to the year 1494, when a new franciscan house is open, according to the «Observancia» (rules. We analyze the space framework where the friars Uve and their influence in the religious, political and civil Ufe of the city. In short, it is a preliminary approach to the phenomenon of local franciscanism during a period of growth and development of the city.

  18. Modeling the Gila-San Francisco Basin using system dynamics in support of the 2004 Arizona Water Settlement Act.

    Energy Technology Data Exchange (ETDEWEB)

    Tidwell, Vincent Carroll; Sun, Amy Cha-Tien; Peplinski, William J.; Klise, Geoffrey Taylor

    2012-04-01

    Water resource management requires collaborative solutions that cross institutional and political boundaries. This work describes the development and use of a computer-based tool for assessing the impact of additional water allocation from the Gila River and the San Francisco River prescribed in the 2004 Arizona Water Settlements Act. Between 2005 and 2010, Sandia National Laboratories engaged concerned citizens, local water stakeholders, and key federal and state agencies to collaboratively create the Gila-San Francisco Decision Support Tool. Based on principles of system dynamics, the tool is founded on a hydrologic balance of surface water, groundwater, and their associated coupling between water resources and demands. The tool is fitted with a user interface to facilitate sensitivity studies of various water supply and demand scenarios. The model also projects the consumptive use of water in the region as well as the potential CUFA (Consumptive Use and Forbearance Agreement which stipulates when and where Arizona Water Settlements Act diversions can be made) diversion over a 26-year horizon. Scenarios are selected to enhance our understanding of the potential human impacts on the rivers ecological health in New Mexico; in particular, different case studies thematic to water conservation, water rights, and minimum flow are tested using the model. The impact on potential CUFA diversions, agricultural consumptive use, and surface water availability are assessed relative to the changes imposed in the scenarios. While it has been difficult to gage the acceptance level from the stakeholders, the technical information that the model provides are valuable for facilitating dialogues in the context of the new settlement.

  19. Understanding processes controlling sediment transports at the mouth of a highly energetic inlet system (San Francisco Bay, CA)

    Science.gov (United States)

    Elias, Edwin P.L.; Hansen, Jeff E.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    San Francisco Bay is one of the largest estuaries along the U.S. West Coast and is linked to the Pacific Ocean through the Golden Gate, a 100 m deep bedrock inlet. A coupled wave, flow and sediment transport model is used to quantify the sediment linkages between San Francisco Bay, the Golden Gate, and the adjacent open coast. Flow and sediment transport processes are investigated using an ensemble average of 24 climatologically derived wave cases and a 24.8 h representative tidal cycle. The model simulations show that within the inlet, flow and sediment transport is tidally dominated and driven by asymmetry of the ebb and flood tides. Peak ebb velocities exceed the peak flood velocities in the narrow Golden Gate channel as a result of flow convergence and acceleration. Persistent flow and sediment gyres at the headland tips are formed that limit sediment transfer from the ebb-tidal delta to the inlet and into the bay. The residual transport pattern in the inlet is dominated by a lateral segregation with a large ebb-dominant sediment transport (and flow) prevailing along the deeper north side of the Golden Gate channel, and smaller flood dominant transports along the shallow southern margin. The seaward edge of the ebb-tidal delta largely corresponds to the seaward extent of strong tidal flows. On the ebb-tidal delta, both waves and tidal forcing govern flow and sediment transport. Wave focusing by the ebb-tidal delta leads to strong patterns of sediment convergence and divergence along the adjacent Ocean Beach.

  20. Enabling full representation in science: the San Francisco BUILD project's agents of change affirm science skills, belonging and community.

    Science.gov (United States)

    Estrada, Mica; Eroy-Reveles, Alegra; Ben-Zeev, Avi; Baird, Teaster; Domingo, Carmen; Gómez, Cynthia A; Bibbins-Domingo, Kirsten; Parangan-Smith, Audrey; Márquez-Magaña, Leticia

    2017-01-01

    The underrepresentation of minority students in the sciences constrains innovation and productivity in the U.S. The SF BUILD project mission is to remove barriers to diversity by taking a "fix the institution" approach rather than a "fix the student" one. SF BUILD is transforming education, research, training, and mentoring at San Francisco State University, a premiere public university that primarily serves undergraduates and ethnic minority students. It boasts a large number of faculty members from underrepresented groups (URGs), including many of the project leaders. These leaders collaborate with faculty at the University of California San Francisco (UCSF), a world-class medical research institution, to implement SF BUILD. Together, the campus partners are committed to creating intellectually safe and affirming environments grounded in the Signaling Affirmation for Equity (SAFE) model, which is based on robust psychosocial evidence on stereotype threat and its consequences. The SAFE model dictates a multilevel approach to increasing intent to pursue a biomedical career, persistence in STEM fields, and productivity (e.g. publications, presentations, and grants) by implementing transformative activities at the institutional, faculty, and student levels. These activities (1) increase knowledge of the stereotype threat phenomenon; (2) affirm communal and altruistic goals of students and faculty to "give back" to their communities in classrooms and research activities; and (3) establish communities of students, faculty and administrators as "agents of change." Agents of change are persons committed to establishing and maintaining SAFE environments. In this way, SF BUILD advances the national capacity to address biomedical questions relevant to communities of color by enabling full representation in science. This chapter describes the theoretical and historical context that drive the activities, research and evaluation of the SF BUILD project, and highlights

  1. San Francisco Bay-Delta bathymetric/topographic digital elevation model(DEM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A high-resolution (10-meter per pixel) digital elevation model (DEM) was created for the Sacramento-San Joaquin Delta using both bathymetry and topography data. This...

  2. Interview with Jaime Córtez, Program Manager at the Galería de la Raza, San Francisco, CA, USA, August 14, 2001 Entretien avec Jaime Córtez, directeur de la programmation, Galería de la Raza, San Francisco, CA, États-Unis

    Directory of Open Access Journals (Sweden)

    Gérard Selbach

    2009-10-01

    Full Text Available ForewordLocated at 2857 24th Street, just off Mission Street, at the heart of the Hispanic district in San Francisco, is theGalería de la Raza Co-founded by René Yáñez (cf. interview infra and Ralph Maradiaga in 1970, the Galería was initially funded by the San Francisco Neighborhood Arts Program (NAP which provided the salaries of the directors, equipment and a small budget for exhibitions for a dozen years. The opening showed awareness and compromise on the part of the SF City and of art ...

  3. Critical Assessment of the Delta Smelt Population in the San Francisco Estuary, California

    Directory of Open Access Journals (Sweden)

    William A Bennett

    2005-09-01

    Full Text Available The delta smelt (Hypomesus transpacificus is a small and relatively obscure fish that has recently risen to become a major focus of environmental concern in California. It was formally abundant in the low-salinity and freshwater habitats of the northeastern San Francisco Estuary, but is now listed as threatened under the Federal and California State Endangered Species Acts. In the decade following the listings scientific understanding has increased substantially, yet several key aspects of its biology and ecological relationships within the highly urbanized estuary remain uncertain. A key area of controversy centers on impacts to delta smelt associated with exporting large volumes of freshwater from the estuary to supply California’s significant agricultural and urban water demands. The lack of appropriate data, however, impedes efforts to resolve these issues and develop sound management and restoration alternatives. Delta smelt has an unusual life history strategy relative to many fishes. Some aspects of its biology are similar to other coastal fishes, particularly salmonids. Smelts in the genus, Hypomesus, occur throughout the Pacific Rim, have variable life history strategies, and are able to adapt rapidly to local environments. By comparison, delta smelt has a tiny geographic range being confined to a thin margin of low salinity habitat in the estuary. It primarily lives only a year, has relatively low fecundity, and pelagic larvae; life history attributes that are unusual when compared with many fishes worldwide. A small proportion of delta smelt lives two years. These individuals are relatively highly fecund but are so few in number that their reproductive contribution only may be of benefit to the population after years of extremely poor spawning success and survival. Provisioning of reproductive effort by these older fish may reflect a bet-hedging tactic to insure population persistence. Overall, the population persists by maximizing

  4. Effects of Acknowledging Uncertainty about Earthquake Risk Estimates on San Francisco Bay Area Residents' Beliefs, Attitudes, and Intentions.

    Science.gov (United States)

    Nakayachi, Kazuya; B Johnson, Branden; Koketsu, Kazuki

    2017-08-29

    We test here the risk communication proposition that explicit expert acknowledgment of uncertainty in risk estimates can enhance trust and other reactions. We manipulated such a scientific uncertainty message, accompanied by probabilities (20%, 70%, implicit ["will occur"] 100%) and time periods (10 or 30 years) in major (≥magnitude 8) earthquake risk estimates to test potential effects on residents potentially affected by seismic activity on the San Andreas fault in the San Francisco Bay Area (n = 750). The uncertainty acknowledgment increased belief that these specific experts were more honest and open, and led to statistically (but not substantively) significant increases in trust in seismic experts generally only for the 20% probability (vs. certainty) and shorter versus longer time period. The acknowledgment did not change judged risk, preparedness intentions, or mitigation policy support. Probability effects independent of the explicit admission of expert uncertainty were also insignificant except for judged risk, which rose or fell slightly depending upon the measure of judged risk used. Overall, both qualitative expressions of uncertainty and quantitative probabilities had limited effects on public reaction. These results imply that both theoretical arguments for positive effects, and practitioners' potential concerns for negative effects, of uncertainty expression may have been overblown. There may be good reasons to still acknowledge experts' uncertainties, but those merit separate justification and their own empirical tests. © 2017 Society for Risk Analysis.

  5. Riders on the storm: selective tidal movements facilitate the spawning migration of threatened delta smelt in the San Francisco Estuary

    Science.gov (United States)

    Bennett, W.A.; Burau, Jon R.

    2015-01-01

    Migration strategies in estuarine fishes typically include behavioral adaptations for reducing energetic costs and mortality during travel to optimize reproductive success. The influence of tidal currents and water turbidity on individual movement behavior were investigated during the spawning migration of the threatened delta smelt, Hypomesus transpacificus, in the northern San Francisco Estuary, California, USA. Water current velocities and turbidity levels were measured concurrently with delta smelt occurrence at sites in the lower Sacramento River and San Joaquin River as turbidity increased due to first-flush winter rainstorms in January and December 2010. The presence/absence of fish at the shoal-channel interface and near the shoreline was quantified hourly over complete tidal cycles. Delta smelt were caught consistently at the shoal-channel interface during flood tides and near the shoreline during ebb tides in the turbid Sacramento River, but were rare in the clearer San Joaquin River. The apparent selective tidal movements by delta smelt would facilitate either maintaining position or moving upriver on flood tides, and minimizing advection down-estuary on ebb tides. These movements also may reflect responses to lateral gradients in water turbidity created by temporal lags in tidal velocities between the near-shore and mid-channel habitats. This migration strategy can minimize the energy spent swimming against strong river and tidal currents, as well as predation risks by remaining in turbid water. Selection pressure on individuals to remain in turbid water may underlie population-level observations suggesting that turbidity is a key habitat feature and cue initiating the delta smelt spawning migration.

  6. A Place to Call Home: A Synthesis of Delta Smelt Habitat in the Upper San Francisco Estuary

    Directory of Open Access Journals (Sweden)

    Ted Sommer

    2013-06-01

    Full Text Available We used a combination of published literature and field survey data to synthesize the available information about habitat use by delta smelt Hypomesus transpacificus, a declining native species in the San Francisco Estuary. Delta smelt habitat ranges from San Pablo and Suisun bays to their freshwater tributaries, including the Sacramento and San Joaquin rivers. In recent years, substantial numbers of delta smelt have colonized habitat in Liberty Island, a north Delta area that flooded in 1997. The species has a more upstream distribution during spawning as opposed to juvenile rearing periods. Post-larvae and juveniles tend to have a more downstream distribution during wetter years. Delta smelt are most common in low-salinity habitat (<6 psu with high turbidities (>12 NTU and moderate temperatures (7 °C to 25 °C. They do not appear to have strong substrate preferences, but sandy shoals are important for spawning in other osmerids. The evidence to date suggests that they generally require at least some tidal flow in their habitats. Delta smelt also occur in a wide range of channel sizes, although they seem to be rarer in small channels (<15 m wide. Nonetheless, there is some evidence that open water adjacent to habitats with long water-residence times (e.g. tidal marsh, shoal, low-order channels may be favorable. Other desirable features of delta smelt habitat include high calanoid copepod densities and low levels of submerged aquatic vegetation (SAV and the toxic algae Microcystis. Although enough is known to plan for large-scale pilot habitat projects, these efforts are vulnerable to several factors, most notably climate change, which will change salinity regimes and increase the occurrence of lethal temperatures. We recommend restoration of multiple geographical regions and habitats coupled with extensive monitoring and adaptive management. An overall emphasis on ecosystem processes rather than specific habitat features is also likely to be

  7. Final Environmental Assessment : Opening waterfowl hunting on 5,500 acres of former commercial salt ponds : Don Edwards San Francisco Bay National Wildlife Refuge : Alviso and Ravenswood Salt Ponds

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This EA for opening waterfowl hunting on salt ponds recently acquired by the Don Edwards San Francisco Bay National Wildlife Refuge proposes three alternatives....

  8. Du savetier au financier: la famille Borel, de Neuchâtel à San Francisco: le cable car... propriété de banquiers suisses cosmopolites ? : pistes pour le financement privé d'infrastructures urbaines publiques

    OpenAIRE

    Wasserfallen, Antoine; Thalmann, Philippe

    2005-01-01

    The Borel Family From Neuchâtel to San Francisco : From shoemaker to banker Did you know that the Cable Car was owned by Swiss citizens? BACKTRACKING : PRIVATE FINANCING OF PUBLIC METROPOLITAN INFRASTRUCTURES Executive Summary: Did you know that one of San Francisco most famous fixtures, the Cable car, was owned by Swiss citizens? Through this detailed study of the Borel family, and its business and investment plans we will observe an example of private financing o...

  9. Du savetier au financier: la famille Borel, de Neuchâtel à San Francisco: le cable car... propriété de banquiers suisses cosmopolites ? : pistes pour le financement privé d'infrastructures urbaines publiques

    OpenAIRE

    Wasserfallen, Antoine

    1999-01-01

    The Borel Family From Neuchâtel to San Francisco : From shoemaker to banker Did you know that the Cable Car was owned by Swiss citizens? BACKTRACKING : PRIVATE FINANCING OF PUBLIC METROPOLITAN INFRASTRUCTURES Executive Summary: Did you know that one of San Francisco most famous fixtures, the Cable car, was owned by Swiss citizens? Through this detailed study of the Borel family, and its business and investment plans we will observe an example of private financing of pu...

  10. 33 CFR 167.400 - Off San Francisco Traffic Separation Scheme: General.

    Science.gov (United States)

    2010-07-01

    ... Separation Scheme: General. 167.400 Section 167.400 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY OFFSHORE TRAFFIC SEPARATION SCHEMES Description of Traffic Separation Schemes and Precautionary Areas Pacific West Coast § 167.400 Off San...

  11. Mudflat Morphodynamics and the Impact of Sea Level Rise in South San Francisco Bay

    NARCIS (Netherlands)

    van der Wegen, Mick; Jaffe, Bruce E.; Foxgrover, Amy; Roelvink, D.

    2016-01-01

    Estuarine tidal mudflats form unique habitats and maintain valuable ecosystems. Historic measurements of a mudflat in San Fancsico Bay over the past 150 years suggest the development of a rather stable mudflat profile. This raises questions on its origin and governing processes as well as on the

  12. Selenium and stable isotopes of carbon and nitrogen in the benthic clam Corbula amurensis from Northern San Francisco Bay, California: May 1995-February 2010

    Science.gov (United States)

    Kleckner, Amy E.; Stewart, A. Robin; Luoma, Samuel N.

    2010-01-01

    The clam-based food webs of San Francisco Bay, California efficiently bioaccumlate selenium and thus provide pathways for exposure to predators important to the estuary. This study documents changes in monthly selenium concentrations for the clam Corbula amurensis, a keystone species of the estuary, at five locations in northern San Francisco Bay from 1995 through 2010. Samples were collected from designated U.S. Geological Survey stations and prepared and analyzed by U.S. Geological Survey methods. Stable isotopes of carbon and nitrogen in soft tissues of clams also were measured as an indicator of sources of selenium for the clams. These monitoring data indicate that clam selenium concentrations ranged from a low of 2 to a high of 22 micrograms per gram dry weight with strong spatial and seasonal variation over the period of study.

  13. Sexual mixing and the risk environment of sexually active transgender women: data from a respondent-driven sampling study of HIV risk among transwomen in San Francisco, 2010.

    Science.gov (United States)

    Wilson, Erin C; Santos, Glen-Milo; Raymond, H Fisher

    2014-08-06

    Research on the sexual networks of transwomen is central to explaining higher HIV risk for this population. This study examined HIV risk behaviors and sexual mixing patterns of transwomen by demographic and HIV-related risk behaviors. Data were obtained from a 2010 study of HIV risk for transwomen in San Francisco. Assortativity by race, partner type, HIV serostatus, and IDU across sexual networks was calculated using Newman's assortativity coefficient (NC). Multivariable generalized estimating equations (GEE) logistic regression models were used to evaluate associations between unprotected anal intercourse with race and HIV serostatus, partner-IDU status and relationship type discordance while adjusting for the HIV status of transwomen. There were 235 sexually active transwomen in this study, of whom 104 (44.3%) were HIV-positive and 73 (31.1%) had a history of injection drug use. Within the 575 partnerships, African American/black and Latina transwomen were the most racially assortative (NC 0.40, 95% CI 0.34-0.45, and NC 0.43, 95% CI 0.38-0.49, respectively). In partnerships where the partner's HIV status was known (n = 309, 53.7%), most transwomen were in sexual partnerships with people of their same known serostatus (71.8%, n = 222). In multivariable analyses, unprotected anal intercourse was significantly associated with primary partners, having a sexual partner who was an injection drug user, and sexual partner seroconcordance. Public health efforts to reduce transwomen's HIV risk would likely benefit from prioritizing prevention efforts to risk reduction within IDU-discordant and primary partnerships, determining risks attributable to sexual network characteristics, and actively addressing injection drug use among transwomen.

  14. How Does Geography Matter in Ethnic Labor Market Segmentation Process? A Case Study of Chinese Immigrants in the San Francisco CMSA

    OpenAIRE

    Qingfang Wang

    2007-01-01

    In the context of continuing influxes of large numbers of immigrants to the United States, urban labor market segmentation along the lines of race/ethnicity, gender, and class has drawn considerable growing attention. Using a confidential dataset extracted from the United States Decennial Long Form Data 2000 and a multilevel regression modeling strategy, this paper presents a case study of Chinese immigrants in the San Francisco metropolitan area. Correspondent with the highly segregated natu...

  15. The Biology and Ecology of Lepidium latifolium L. in the San Francisco Estuary and their Implications for Eradication of this Invasive Weed

    OpenAIRE

    Spenst, Renée O.

    2006-01-01

    Lepidium latifolium (perennial pepperweed) is a widespread and invasive weed that is problematic throughout the western United States, and internationally. The aim of this research is improve understanding of L. latifolium biology and ecology and the influence of each on control efficacy in San Francisco Estuary tidal wetlands, with particular regard for variation along the salinity gradients in the estuary. To address these issues, I conducted three discrete but related analyses: 1) examined...

  16. Physicians' communication with patients about adherence to HIV medication in San Francisco and Copenhagen: a qualitative study using Grounded Theory

    Directory of Open Access Journals (Sweden)

    Rubow Cecilie

    2006-12-01

    Full Text Available Abstract Background Poor adherence is the main barrier to the effectiveness of HIV medication. The objective of this study was to explore and conceptualize patterns and difficulties in physicians' work with patients' adherence to HIV medication. No previous studies on this subject have directly observed physicians' behavior. Methods This is a qualitative, cross-sectional study. We used a Grounded Theory approach to let the main issues in physicians' work with patients' adherence emerge without preconceiving the focus of the study. We included physicians from HIV clinics in San Francisco, U.S.A. as well as from Copenhagen, Denmark. Physicians were observed during their clinical work and subsequently interviewed with a semi-structured interview guide. Notes on observations and transcribed interviews were analyzed with NVivo software. Results We enrolled 16 physicians from San Francisco and 18 from Copenhagen. When we discovered that physicians and patients seldom discussed adherence issues in depth, we made adherence communication and its barriers the focus of the study. The main patterns in physicians' communication with patients about adherence were similar in both settings. An important barrier to in-depth adherence communication was that some physicians felt it was awkward to explore the possibility of non-adherence if there were no objective signs of treatment failure, because patients could feel "accused." To overcome this awkwardness, some physicians consciously tried to "de-shame" patients regarding non-adherence. However, a recurring theme was that physicians often suspected non-adherence even when patients did not admit to have missed any doses, and physicians had difficulties handling this low believability of patient statements. We here develop a simple four-step, three-factor model of physicians' adherence communication. The four steps are: deciding whether to ask about adherence or not, pre-questioning preparations, phrasing the

  17. Prehistoric Agriculture and Soil Fertility on Lava Flows in Northern Arizona, USA: Results from the San Francisco Volcanic Field REU

    Science.gov (United States)

    Broadman, E.; Anderson, K. C.

    2013-12-01

    The San Francisco Volcanic Field in northern Arizona is home to ~600 cinder cones, the youngest of which is Sunset Crater (erupted ~AD 1100). This study documents trends in available phosphate and nitrate content with time, testing whether lowered soil pH from the addition of Sunset cinders increased soil fertility and became a factor in Anasazi agricultural success. Soil fertility is examined both before and after Sunset's eruption in soils of different ages that have developed from eolian deposition on top of lava flows. An increase in phosphate and nitrate levels following acidification would suggest that the presence of Sunset cinders brought the soils to the optimal pH for mobilization of these nutrients. The combined effects of the cinder layer retaining nutrients and water, wetter climates, and increases in phosphate and nitrate (both limiting nutrients for plant growth), would have contributed to Anasazi agricultural success after Sunset's eruption. Samples for this study were taken from eolian-derived soils of different ages atop lava flows in the San Francisco Volcanic Field. OSL data from these soils on Strawberry and SP Craters' lava flows yielded age estimates of ~12.3 ka (Strawberry) and ~32.7 ka (SP), on which a soil chronosequence was based. Results from the chronosequence supported these OSL ages, indicating that soils on the SP flow are older than those on the Strawberry flow. Field descriptions, Harden Development Indices, particle size analysis, and nutrient content analysis were used for this aspect of the project. An experimental acid wash method will be used to simulate the addition of Sunset's acidic cinders, and will yield data for phosphate and nitrate content after Sunset erupted. Preliminary results indicate that phosphate and nitrate accumulate in upper, eolian-derived horizons (Av, Bw) and in more deeply buried carbonate horizons (Bk). Higher concentrations of phosphate and nitrate were found in older (SP) soils than younger

  18. HCV screening in a cohort of HIV infected and uninfected homeless and marginally housed women in San Francisco, California

    Directory of Open Access Journals (Sweden)

    Kimberly Page

    2017-02-01

    Full Text Available Abstract Background Hepatitis C virus (HCV screening has taken on new importance as a result of updated guidelines and new curative therapies. Relatively few studies have assessed HCV infection in homeless populations, and a minority include women. We assessed prevalence and correlates of HCV exposure in a cohort of homeless and unstably housed women in San Francisco, and estimated the proportion undiagnosed. Methods A probability sample of 246 women were recruited at free meal programs, homeless shelters, and low-cost single room occupancy hotels in San Francisco; women with HIV were oversampled. At baseline, anti-HCV status was assessed using an enzyme immunoassay, and results compared in both HIV-positive and negative women. Exposures were assessed by self-report. Logistic regression was used to assess factors independently associated th HCV exposure. Results Among 246 women 45.9% were anti-HCV positive, of whom 61.1% were HIV coinfected; 27.4% of positives reported no prior screening. Most (72% women were in the ‘baby-boomer’ birth cohort; 19% reported recent injection drug use (IDU. Factors independently associated with anti-HCV positivity were: being born in 1965 or earlier (AOR 3.94; 95%CI: 1.88, 8.26, IDU history (AOR 4.0; 95%CI: 1.68, 9.55, and number of psychiatric diagnoses (AOR 1.16; 95%CI: 1.08, 1.25. Conclusions Results fill an important gap in information regarding HCV among homeless women, and confirm the need for enhanced screening in this population where a high proportion are baby-boomers and have a history of drug use and psychiatric problems. Due to their age and risk profile, there is a high probability that women in this study have been infected for decades, and thus have significant liver disease. The association with mental illness and HCV suggests that in addition increased screening, augmenting mental health care and support may enhance treatment success.

  19. Comparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California

    Science.gov (United States)

    McKee, L.J.; Lewicki, M.; Schoellhamer, D.H.; Ganju, N.K.

    2013-01-01

    Quantifying suspended sediment loads is important for managing the world's estuaries in the context of navigation, pollutant transport, wetland restoration, and coastal erosion. To address these needs, a comprehensive analysis was completed on sediment supply to San Francisco Bay from fluvial sources. Suspended sediment, optical backscatter, velocity data near the head of the estuary, and discharge data obtained from the output of a water balance model were used to generate continuous suspended sediment concentration records and compute loads to the Bay from the large Central Valley watershed. Sediment loads from small tributary watersheds around the Bay were determined using 235 station-years of suspended sediment data from 38 watershed locations, regression analysis, and simple modeling. Over 16 years, net annual suspended sediment load to the head of the estuary from its 154,000 km2 Central Valley watershed varied from 0.13 to 2.58 (mean = 0.89) million metric t of suspended sediment, or an average yield of 11 metric t/km2/yr. Small tributaries, totaling 8145 km2, in the nine-county Bay Area discharged between 0.081 and 4.27 (mean = 1.39) million metric t with a mean yield of 212 metric t/km2/yr. The results indicate that the hundreds of urbanized and tectonically active tributaries adjacent to the Bay, which together account for just 5% of the total watershed area draining to the Bay and provide just 7% of the annual average fluvial flow, supply 61% of the suspended sediment. The small tributary loads are more variable (53-fold between years compared to 21-fold for the inland Central Valley rivers) and dominated fluvial sediment supply to the Bay during 10 out of 16 yr. If San Francisco Bay is typical of other estuaries in active tectonic or climatically variable coastal regimes, managers responsible for water quality, dredging and reusing sediment accumulating in shipping channels, or restoring wetlands in the world's estuaries may need to more carefully

  20. Mercury concentrations and space use of pre-breeding American avocets and black-necked stilts in San Francisco Bay

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.; Takekawa, John Y.; Demers, Scott A.; Adelsbach, Terrence L.; Bluso, J.D.; Miles, A. Keith; Warnock, Nils; Suchanek, Thomas H.; Schwarzbach, Steven E.

    2007-01-01

    We examined factors influencing mercury concentrations in pre-breeding American avocets (Recurvirostra americana) and black-necked stilts (Himantopus mexicanus), the two most abundant breeding shorebirds in San Francisco Bay, California. We tested the effects of species, site, sex, year, and date on total mercury concentrations in blood of pre-breeding adult birds and used radio telemetry to determine space use and sites of dietary mercury exposure. We collected blood from 373 avocets and 157 stilts from February to April in 2005 and 2006, radio-marked and tracked 115 avocets and 94 stilts, and obtained 2393 avocet and 1928 stilt telemetry locations. Capture site was the most important factor influencing mercury concentrations in birds, followed by species and sex. Mercury concentrations were higher in stilts (geometric mean: 1.09 μg g− 1 wet weight [ww]) than in avocets (0.25 μg g− 1 ww) and males (stilts: 1.32 μg g− 1 ww; avocets: 0.32 μg g− 1 ww) had higher levels than females (stilts: 1.15 μg g− 1 ww; avocets: 0.21 μg g− 1 ww). Mercury concentrations were highest for both species at the southern end of San Francisco Bay, especially in salt pond A8 (stilts: 3.31 μg g− 1 ww; avocets: 0.58 μg g− 1 ww). Radio telemetry data showed that birds had strong fidelity to their capture site. Avocets primarily used salt ponds, tidal marshes, tidal flats, and managed marshes, whereas stilts mainly used salt ponds, managed marshes, and tidal marshes. Our results suggest that variation in blood mercury concentrations among sites was attributed to differences in foraging areas, and species differences in habitat use and foraging strategies may increase mercury exposure in stilts more than avocets.

  1. Dosimetry in occupational exposure workers of the medical institutes of the University San Francisco Xavier de Chuquisaca; Dosimetria en TOEs de los institutos medicos de la Universidad San Francisco Xavier de Chuquisaca

    Energy Technology Data Exchange (ETDEWEB)

    Zambrana Z, A. J.; Castro S, O.; Huanca S, E.; Torrez C, M. [Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, Instituto de Medicina Nuclear de Sucre, Plaza Libertad No. 1, Sucre (Bolivia, Plurinational State of); Villca Q, I., E-mail: nuclear_sre@entelnet.bo [Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, Instituto Nacional de Cancerologia Dr. Jose Cupertino Arteaga, Plaza Libertad No. 1, Sucre (Bolivia, Plurinational State of)

    2014-08-15

    In this work is made a retrospective analysis of the record, of the dosimetric control readings processed by the Dosimetry Laboratory of the Instituto Boliviano de Ciencia y Tecnologia Nuclear, as regulator entity at national level for Occupational Exposed Workers (OEWs) to ionizing radiations, of the Medical Institutes of the Universidad Mayor, Real y Pontificia de San Francisco Xavier de Chuquisaca, by a period of 10 and 15 years. The results showed that in the Nuclear Medicine Institute of Sucre, the Accumulated Occupational Exposure of a total of 393 readings of 15 OEWs was of 20.4 mSv, identifying as maximum value 10.2 mSv, in the official that develops the Radio-pharmacy activities (elution, fractionation, preparation and management). In the Instituto Nacional de Cancerologia Dr. Jose Cupertino Arteaga the dosimetric background registered an Accumulated Occupational Exposure of a total of 1319 readings of 50 OEWs of 309.69 mSv, with a maximum value of 62.30 mSv, corresponding to the worker of the technical area (maintenance, adjustment and calibration). Comparison that allows to infer that the difference is due mainly to the radio-active source type {sup 99m}Tc Vs {sup 60}Co utilized in these health centers. (Author)

  2. A Tale of Two Cities: Access to Care and Services Among African-American Transgender Women in Oakland and San Francisco.

    Science.gov (United States)

    Nemoto, Tooru; Cruz, Taylor M; Iwamoto, Mariko; Sakata, Maria

    2015-09-01

    The San Francisco Bay Area attracts people from all over the country due to the perception of lesbian, gay, bisexual, and transgender (LGBT) acceptance and affirmation. African-American transgender women are severely marginalized across society and as such have many unmet health and social service needs. This study sought to quantitatively assess unmet needs among African-American transgender women with a history of sex work by comparing residents of Oakland versus San Francisco. A total of 235 African-American transgender women were recruited from San Francisco (n=112) and Oakland (n=123) through community outreach and in collaboration with AIDS service organizations. Participants were surveyed regarding basic, health, and social needs and HIV risk behaviors. Pearson Chi-squared tests and a linear regression model examined associations between city of residence and unmet needs. While participants from both cities reported unmet needs, Oakland participants had a greater number of unmet needs in receiving basic assistance, mental health treatment, and health care services. Oakland participants also reported less transgender community identification but higher social support from the family. These findings demonstrate the enormity of African-American transgender women's needs within the Bay Area. Greater resources are needed for social service provision targeting this marginalized group of people, particularly in Oakland.

  3. Deep nirS amplicon sequencing of San Francisco Bay sediments enables prediction of geography and environmental conditions from denitrifying community composition.

    Science.gov (United States)

    Lee, Jessica A; Francis, Christopher A

    2017-12-01

    Denitrification is a dominant nitrogen loss process in the sediments of San Francisco Bay. In this study, we sought to understand the ecology of denitrifying bacteria by using next-generation sequencing (NGS) to survey the diversity of a denitrification functional gene, nirS (encoding cytchrome-cd 1 nitrite reductase), along the salinity gradient of San Francisco Bay over the course of a year. We compared our dataset to a library of nirS sequences obtained previously from the same samples by standard PCR cloning and Sanger sequencing, and showed that both methods similarly demonstrated geography, salinity and, to a lesser extent, nitrogen, to be strong determinants of community composition. Furthermore, the depth afforded by NGS enabled novel techniques for measuring the association between environment and community composition. We used Random Forests modelling to demonstrate that the site and salinity of a sample could be predicted from its nirS sequences, and to identify indicator taxa associated with those environmental characteristics. This work contributes significantly to our understanding of the distribution and dynamics of denitrifying communities in San Francisco Bay, and provides valuable tools for the further study of this key N-cycling guild in all estuarine systems. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Effects of switching to lower sulfur marine fuel oil on air quality in the San Francisco Bay area.

    Science.gov (United States)

    Tao, Ling; Fairley, David; Kleeman, Michael J; Harley, Robert A

    2013-09-17

    Ocean-going vessels burning high-sulfur heavy fuel oil are an important source of air pollutants, such as sulfur dioxide and particulate matter. Beginning in July 2009, an emission control area was put into effect at ports and along the California coastline, requiring use of lower sulfur fuels in place of heavy fuel oil in main engines of ships. To assess impacts of the fuel changes on air quality at the Port of Oakland and in the surrounding San Francisco Bay area, we analyzed speciated fine particle concentration data from four urban sites and two more remote sites. Measured changes in concentrations of vanadium, a specific marker for heavy fuel oil combustion, are related to overall changes in aerosol emissions from ships. We found a substantial reduction in vanadium concentrations after the fuel change and a 28-72% decrease in SO2 concentrations, with the SO2 decrease varying depending on proximity to shipping lanes. We estimate that the changes in ship fuel reduced ambient PM2.5 mass concentrations at urban sites in the Bay area by about 3.1 ± 0.6% or 0.28 ± 0.05 μg/m(3). The largest contributing factor to lower PM mass concentrations was reductions in particulate sulfate. Absolute sulfate reductions were fairly consistent across sites, whereas trace metal reductions were largest at a monitoring site in West Oakland near the port.

  5. Serum biomarkers of polyfluoroalkyl compound exposure in young girls in Greater Cincinnati and the San Francisco Bay Area, USA.

    Science.gov (United States)

    Pinney, Susan M; Biro, Frank M; Windham, Gayle C; Herrick, Robert L; Yaghjyan, Lusine; Calafat, Antonia M; Succop, Paul; Sucharew, Heidi; Ball, Kathleen M; Kato, Kayoko; Kushi, Lawrence H; Bornschein, Robert

    2014-01-01

    PFC serum concentrations were measured in 6-8 year-old girls in Greater Cincinnati (GC) (N = 353) and the San Francisco Bay Area (SFBA) (N = 351). PFOA median concentration was lower in the SFBA than GC (5.8 vs. 7.3 ng/mL). In GC, 48/51 girls living in one area had PFOA concentrations above the NHANES 95th percentile for children 12-19 years (8.4 ng/mL), median 22.0 ng/mL. The duration of being breast fed was associated with higher serum PFOA at both sites and with higher PFOS, PFHxS and Me-PFOSA-AcOH concentrations in GC. Correlations of the PFC analytes with each other suggest that a source upriver from GC may have contributed to exposures through drinking water, and water treatment with granular activated carbon filtration resulted in less exposure for SWO girls compared to those in NKY. PFOA has been characterized as a drinking water contaminant, and water treatment systems effective in removing PFCs will reduce body burdens. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Impact of a Structural Intervention to Address Alcohol Use Among Gay Bar Patrons in San Francisco: The PACE Study.

    Science.gov (United States)

    Charlebois, Edwin D; Plenty, Albert H; Lin, Jessica; Ayala, Alicia; Hecht, Jennifer

    2017-11-01

    We evaluated the impact on alcohol intake and blood alcohol concentration (BAC) of a multi-level structural intervention to increase the availability of free water, coupled with messaging on pacing alcohol intake and normative feedback of blood alcohol concentration in a convenience sample of gay bars in San Francisco. Participants (n = 1,293) were recruited among exiting patrons of four gay bars (two intervention bars and two control bars). Participants were surveyed on alcohol intake and BAC was measured by breathalyzer. Prior to the intervention there were no significant differences in baseline alcohol measures between intervention and control bars. Post-intervention there were significant differences on objective and subjective measures of alcohol consumption: 30% of intervention bar participants had BAC% levels over the legal driving limit (0.08%) compared to 43% of control bar participants, p < 0.0001 and 78% of intervention bar participants were above the AUDIT-C cut-off for hazardous drinking compared to 87% in control bars, p < 0.001.

  7. Mortality among young injection drug users in San Francisco: a 10-year follow-up of the UFO study.

    Science.gov (United States)

    Evans, Jennifer L; Tsui, Judith I; Hahn, Judith A; Davidson, Peter J; Lum, Paula J; Page, Kimberly

    2012-02-15

    This study examined associations between mortality and demographic and risk characteristics among young injection drug users in San Francisco, California, and compared the mortality rate with that of the population. A total of 644 young (UFO ("U Find Out") Study, from November 1997 to December 2007. Using the National Death Index, the authors identified 38 deaths over 4,167 person-years of follow-up, yielding a mortality rate of 9.1 (95% confidence interval: 6.6, 12.5) per 1,000 person-years. This mortality rate was 10 times that of the general population. The leading causes of death were overdose (57.9%), self-inflicted injury (13.2%), trauma/accidents (10.5%), and injection drug user-related medical conditions (13.1%). Mortality incidence was significantly higher among those who reported injecting heroin most days in the past month (adjusted hazard ratio = 5.8, 95% confidence interval: 1.4, 24.3). The leading cause of death in this group was overdose, and primary use of heroin was the only significant risk factor for death observed in the study. These findings highlight the continued need for public health interventions that address the risk of overdose in this population in order to reduce premature deaths.

  8. Adjustment of the San Francisco estuary and watershed to decreasing sediment supply in the 20th century

    Science.gov (United States)

    Schoellhamer, David H.; Wright, Scott A.; Drexler, Judith Z.

    2013-01-01

    The general progression of human land use is an initial disturbance (e.g., deforestation, mining, agricultural expansion, overgrazing, and urbanization) that creates a sediment pulse to an estuary followed by dams that reduce sediment supply. We present a conceptual model of the effects of increasing followed by decreasing sediment supply that includes four sequential regimes, which propagate downstream: a stationary natural regime, transient increasing sediment supply, transient decreasing sediment supply, and a stationary altered regime. The model features characteristic lines that separate the four regimes. Previous studies of the San Francisco Estuary and watershed are synthesized in the context of this conceptual model. Hydraulic mining for gold in the watershed increased sediment supply to the estuary in the late 1800s. Adjustment to decreasing sediment supply began in the watershed and upper estuary around 1900 and in the lower estuary in the 1950s. Large freshwater flow in the late 1990s caused a step adjustment throughout the estuary and watershed. It is likely that the estuary and watershed are still capable of adjusting but further adjustment will be as steps that occur only during greater floods than previously experienced during the adjustment period. Humans are actively managing the system to try to prevent greater floods. If this hypothesis of step changes occurring for larger flows is true, then the return interval of step changes will increase or, if humans successfully control floods in perpetuity, there will be no more step changes.

  9. Mapping Emissions that Affect Air Quality in the San Francisco Bay Area Using Adjoint Method Analysis Tools

    Science.gov (United States)

    Bastien, L. A.; Jin, L.; Brown, N. J.; Harley, R. A.

    2013-12-01

    Processes governing the fate of airborne pollutants and/or their precursors after they are emitted into the atmosphere are highly complex and, for some of them, highly non-linear. Critical gaps remain in our understanding of the detailed relationship between the spatial and temporal distributions of emissions of pollutants and how those emissions affect air quality. Another knowledge gap exists in describing the relevant emission zones of influence that affect region-wide population weighted exposure to air pollution, as opposed to focusing on air quality at specific locations. In this study, the adjoint of the Community Multiscale Air Quality model (CMAQ) is used to map areas of influence for specific pollutants and receptors of interest in the San Francisco Bay Area. Selected receptors are locations that disproportionately experience poor air quality and a population-weighted Bay Area-wide response. Studied pollutants are diesel soot and benzene for primary pollutants and ozone and formaldehyde for secondary pollutants. Emission sources that contribute the most to poor air quality for selected receptors are identified. The effectiveness of targeted versus region-wide emission control strategies is compared.

  10. Hydrological and management responses to scenarios of climate change in the San Francisco Bay-Delta watershed

    Science.gov (United States)

    Knowles, N.; Cronkite-Ratcliff, C.

    2016-12-01

    Downscaled meteorology from CMIP5 climate scenarios were used to drive a model of unimpaired hydrology of the San Francisco Bay-Delta watershed which in turn drove models of operational responses and managed flows. Twenty daily climate change scenarios from WY1980-2099 were evaluated with the goal of producing inflow boundary conditions for a watershed sediment model and a downstream estuarine hydrodynamic model. The resulting time series of managed flows were analyzed for century-scale trends. All of the twenty scenarios portrayed warming trends, and most had increasing annual managed flows. Nearly all exhibited increasing frequency of extreme flows and earlier flow timing downstream of the watershed's major reservoirs. Trends in annual mean flow, flow timing, and frequency of extreme flows were found to be highly correlated across GCM runs. Managed-flow timing trends were driven more by precipitation trends than by trends in air temperature. Scenarios for evaluation by hydrodynamic and ecological models of the Bay-Delta were selected based on these and other trends as part of a large interdisciplinary modeling project aimed at understanding potential ecological impacts in the Bay-Delta estuary of climate change and other major changes, CASCaDE II.

  11. Malignant melanoma slide review project: Patients from non-Kaiser hospitals in the San Francisco Bay Area. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, P. [California Dept. of Health Services, Berkeley, CA (United States)

    1993-01-05

    This project was initiated, in response to concerns that the observed excess of malignant melanoma among employees of Lawrence Livermore National Laboratory (LLNL) might reflect the incidence of disease diagnostically different than that observed in the general population. LLNL sponsored a slide review project, inviting leading dermatopathology experts to independently evaluate pathology slides from LLNL employees diagnosed with melanoma and those from a matched sample of Bay Area melanoma patients who did not work at the LLNL. The study objectives were to: Identify all 1969--1984 newly diagnosed cases of malignant melanoma among LLNL employees resident in the San Francisco-Oakland Metropolitan Statistical Area, and diagnosed at facilities other than Kaiser Permanente; identify a comparison series of melanoma cases also diagnosed between 1969--1984 in non-Kaiser facilities, and matched as closely as possible to the LLNL case series by gender, race, age at diagnosis, year of diagnosis, and hospital of diagnosis; obtain pathology slides for the identified (LLNL) case and (non-LLNL) comparison patients for review by the LLNL-invited panel of dermatopathology experts; and to compare the pathologic characteristics of the case and comparison melanoma patients, as recorded by the dermatopathology panel.

  12. The Conservation Contributions of Conservation Easements: Analysis of the San Francisco Bay Area Protected Lands Spatial Database

    Directory of Open Access Journals (Sweden)

    Adena R. Rissman

    2008-06-01

    Full Text Available Conservation easements have emerged as an important tool for land trusts and government agencies aiming to conserve private land in the United States. Despite the increase in public investment in conservation easement acquisitions, little is known about their conservation outcomes, particularly at a landscape scale. The nine-county San Francisco Bay Area exemplifies a complex conservation context: 190 organizations hold 24% of the land base in some type of protection status. Using a detailed protected lands database, we compared the contributions of conservation easements and fee-simple protected areas to ecological, agricultural, and public recreation benefits. We found that conservation easements were more likely to conserve grasslands, oak woodlands, and agricultural land, whereas fee-simple properties were more likely to conserve chaparral and scrub, redwoods, and urban areas. Conservation easements contributed to open space connectivity but were unlikely to be integrated into local land-use plans or provide public recreation. In particular, properties held by land trusts were less likely to allow for public recreation than were public lands. Conservation easements held by land trusts and special districts complemented fee-simple lands and provided greater conservation of some ecological communities and agricultural lands than fee-simple properties. Spatial databases of protected areas that include conservation easements are necessary for conservation planning and assessment.

  13. Grazing impact of the invasive clam Corbula amurensis on the microplankton assemblage of the northern San Francisco Estuary

    Science.gov (United States)

    Greene, Valerie E.; Sullivan, Lindsay J.; Thompson, Janet K.; Kimmerer, Wim J.

    2011-01-01

    Grazing by the overbite clam Corbula amurensis (formerly known as Potamocorbula) may be the cause of substantial declines in phytoplankton biomass and zooplankton in the San Francisco Estuary (SFE) following its introduction in 1986. While grazing rates have been examined on bacteria, phytoplankton, and copepod nauplii, the consumption of protistan microzooplankton by C. amurensis has not previously been measured. In this study, laboratory feeding experiments revealed that C. amurensis cleared 0.5 l ind-1 h-1 of microzooplankton (ciliates) and 0.2 l ind-1 h-1 of chlorophyll (chl) a. Despite the higher clearance rate on microzooplankton, clams obtained more of their carbon from phytoplankton, which dominated the prey assemblage on most dates. When the measured clearance rates are extrapolated to field populations of clams, fractional loss rates (50 to 90% d-1) exceed the population growth capacity of microzooplankton. Although microzooplankton may not be a major component of the diet of these clams, C. amurensis may further alter food web dynamics through consumption of this important trophic intermediary, thus disrupting this link from bacteria and phytoplankton to higher trophic levels.

  14. Land rent and housing policy: a case study of the San Francisco Bay area rental housing market.

    Science.gov (United States)

    Barton, Stephen E

    2011-01-01

    In the San Francisco Bay Area, where residential rent is among the highest in the United States, an analysis of data from several sources demonstrates that high rent cannot be accounted for by higher quality, higher operating costs, or higher construction costs. At least one-third of the total rent paid is land rent. Despite increases in real incomes, very-low-income tenants in the Bay Area today have less income remaining after payment of rent than tenants did in 1960. High land rent is a long-term feature of the Bay Area rental market that results mostly from its geography, the density of its urban centers, and a strong economy, rather than from regulatory barriers to new multifamily construction. Deregulation is not a sufficient response to the effects of land rent on low-income tenants. Government should subsidize non-profit housing organizations, particularly land trusts that remove residential land from the market. Taxes on land rent would be a particularly appropriate funding source.

  15. Correlations Between Emerita analoga and Profilicollis spp. as Influenced by Environmetal Factors at Ocean Beach, San Francisco CA

    Science.gov (United States)

    Wright, S.; Garza, F.; Zhang, P.

    2015-12-01

    Since 2002 the Careers in Science (CiS) intern program has monitored Ocean Beach in San Francisco, California for the population of Emerita analoga (Pacific Mole Crab) as part of a partnership program with the Long-term Monitoring Program and Experiential Training for Students (LiMPETS). LiMPETS is an organization that conducts citizen science with Bay Area youth such as the CiS interns. We specifically assist in the collection of Pacific Mole Crab population statistics at Ocean Beach during the summer from June through August. The purpose of collecting Pacific Mole Crabs is to monitor Acanthocephalan parasites (Profilicollis spp.) - to which Pacific Mole Crabs serve as intermediate hosts - and to learn more about our environment as Pacific Mole Crabs are indicator species. During our collections at Ocean Beach we record size, sex, and number of individuals at specific transects. We then take a random sample from the day, return to the lab, and record their sizes, sexes, and Acanthocephalan parasite load. The results of the collection and dissections are then entered into the LiMPETS online database for scientist and researchers to use. Our project will focus on correlations relating to the data collected (Pacific Mole Crab population, parasite load, abiotic and biotic factors, et cetera).

  16. Analysis of sediment, water, and biological samples from the Bay Farm Borrow Area, San Francisco Bay, California

    Energy Technology Data Exchange (ETDEWEB)

    Thom, R.M.; Lefkovitz, L.F. (Battelle/Marine Sciences Lab., Sequim, WA (United States))

    1991-08-01

    The Bay Farm Borrow Area (BFBA) of San Francisco Bay, California, is under consideration as a dredged-material disposal site by the US Army Corps of Engineers (USACE). As part of the analysis of the site, information is required on the quality of benthic biota, sediment, and water in the BFBA. The objective of this report was to provide data on infauna communities, sediment, and water chemistry from samples collected from the BFBA. The samples were collected, and the data will be analyzed by Science Applications International (SAIC). A total of four samples for sediment chemistry, four samples for water chemistry, and 7 samples for infauna communities were analyzed by the Battelle/Marine Sciences Laboratory (MSL). Water analyses included tests for dissolved organic carbon, total suspended solids, four metals, butyltins, polychlorinated biphenyls (PCBs), chlorinated pesticides, polynuclear aromatic hydrocarbons (PAHs), four phenols, and total phenol. Sediment samples were analyzed for percent solids, total organic carbon, total oil and grease, total petroleum hydrocarbons, grain size, 10 metals, butyltins, PCBs, chlorinated pesticides, PAHs, four phenols, and total phenol. The data along with controls and spike recovery analyses, are presented in tables, and the results are discussed in the text. The quality assurance/quality control criteria were met for the analyses as were the detection limits specified by the sponsor.

  17. El proceso de fundación del convento de San Francisco de Valladolid (H. 1220-1275

    Directory of Open Access Journals (Sweden)

    Rojo Alique, Francisco Javier

    2002-12-01

    Full Text Available The foundation of the Franciscan friary at Valladolid, Spain, was a long process, which started in the 1220s with a provisional settlement of friars outside the town, at Rio de Olmos, and finished in 1275, when a new convent was built in the vicinity of Valladolid. We try to establish the relationship between this foundation and the broader process of establishment of Franciscan friaries throughout Europe in the 13th century. We also consider the role that the foundation of the Valladolid convent could play in the settlement strategy of the Friars Minor in the Iberian Peninsula.

    La fundación del convento de San Francisco de Valladolid fue un largo proceso, iniciado en la década de 1220 con un asentamiento provisional de religiosos en el lugar de Río de Olmos, y finalizado en 1275 con la construcción de un nuevo convento en las proximidades de la villa. Se relaciona la fundación vallisoletana con el fenómeno más amplio de la expansión por toda Europa de la Orden Franciscana durante el siglo XIII. Se reflexiona sobre el papel que dicha fundación pudo jugar dentro de la estrategia de implantación de los frailes menores en la Península Ibérica.

  18. Ecosystem variability along the estuarine salinity gradient: Examples from long-term study of San Francisco Bay

    Science.gov (United States)

    Cloern, James E.; Jassby, Alan D.; Schraga, Tara; Kress, Erica S.; Martin, Charles A.

    2017-01-01

    The salinity gradient of estuaries plays a unique and fundamental role in structuring spatial patterns of physical properties, biota, and biogeochemical processes. We use variability along the salinity gradient of San Francisco Bay to illustrate some lessons about the diversity of spatial structures in estuaries and their variability over time. Spatial patterns of dissolved constituents (e.g., silicate) can be linear or nonlinear, depending on the relative importance of river-ocean mixing and internal sinks (diatom uptake). Particles have different spatial patterns because they accumulate in estuarine turbidity maxima formed by the combination of sinking and estuarine circulation. Some constituents have weak or no mean spatial structure along the salinity gradient, reflecting spatially distributed sources along the estuary (nitrate) or atmospheric exchanges that buffer spatial variability of ecosystem metabolism (dissolved oxygen). The density difference between freshwater and seawater establishes stratification in estuaries stronger than the thermal stratification of lakes and oceans. Stratification is strongest around the center of the salinity gradient and when river discharge is high. Spatial distributions of motile organisms are shaped by species-specific adaptations to different salinity ranges (shrimp) and by behavioral responses to environmental variability (northern anchovy). Estuarine spatial patterns change over time scales of events (intrusions of upwelled ocean water), seasons (river inflow), years (annual weather anomalies), and between eras separated by ecosystem disturbances (a species introduction). Each of these lessons is a piece in the puzzle of how estuarine ecosystems are structured and how they differ from the river and ocean ecosystems they bridge.

  19. Health cobenefits and transportation-related reductions in greenhouse gas emissions in the San Francisco Bay area.

    Science.gov (United States)

    Maizlish, Neil; Woodcock, James; Co, Sean; Ostro, Bart; Fanai, Amir; Fairley, David

    2013-04-01

    We quantified health benefits of transportation strategies to reduce greenhouse gas emissions (GHGE). Statistics on travel patterns and injuries, physical activity, fine particulate matter, and GHGE in the San Francisco Bay Area, California, were input to a model that calculated the health impacts of walking and bicycling short distances usually traveled by car or driving low-emission automobiles. We measured the change in disease burden in disability-adjusted life years (DALYs) based on dose-response relationships and the distributions of physical activity, particulate matter, and traffic injuries. Increasing median daily walking and bicycling from 4 to 22 minutes reduced the burden of cardiovascular disease and diabetes by 14% (32,466 DALYs), increased the traffic injury burden by 39% (5907 DALYS), and decreased GHGE by 14%. Low-carbon driving reduced GHGE by 33.5% and cardiorespiratory disease burden by less than 1%. Increased physical activity associated with active transport could generate a large net improvement in population health. Measures would be needed to minimize pedestrian and bicyclist injuries. Together, active transport and low-carbon driving could achieve GHGE reductions sufficient for California to meet legislative mandates.

  20. Integrating terrestrial LiDAR and stereo photogrammetry to map the Tolay lakebed in northern San Francisco Bay

    Science.gov (United States)

    Woo, Isa; Storesund,; Takekawa, John Y.; Gardiner, Rachel J.; Ehret,

    2009-01-01

    The Tolay Creek Watershed drains approximately 3,520 ha along the northern edge of San Francisco Bay. Surrounded by a mosaic of open space conservation easements and public wildlife areas, it is one of the only watersheds in this urbanized estuary that is protected from its headwaters to the bay. Tolay Lake is a seasonal, spring-fed lake found in the upper watershed that historically extended over 120 ha. Although the lakebed was farmed since the early 1860s, the majority of the lakebed was recently acquired by the Sonoma County Regional Parks Department to restore its natural habitat values. As part of the restoration planning process, we produced a digital elevation model (DEM) of the historic extent of Tolay Lake by integrating terrestrial LiDAR (light detection and ranging) and stereo photogrammetry datasets, and real-time kinematic (RTK) global positioning system (GPS) surveys. We integrated the data, generated a DEM of the lakebed and upland areas, and analyzed errors. The accuracy of the composite DEM was verified using spot elevations obtained from the RTK GPS. Thus, we found that by combining photogrammetry, terrestrial LiDAR, and RTK GPS, we created an accurate baseline elevation map to use in watershed restoration planning and design.

  1. Sampling uncharted waters: Examining rearing habitat of larval Longfin Smelt (Spirinchus thaleichthys) in the upper San Francisco Estuary

    Science.gov (United States)

    Grimaldo, Lenny; Feyrer, Frederick; Burns, Jillian; Maniscalco, Donna

    2017-01-01

    The southern-most reproducing Longfin Smelt population occurs in the San Francisco Estuary, California, USA. Long-term monitoring of estuarine habitat for this species has generally only considered deep channels, with little known of the role shallow waters play in supporting their early life stage. To address the need for focused research on shallow-water habitat, a targeted study of Longfin Smelt larvae in littoral habitat was conducted to identify potential rearing habitats during 2013 and 2014. Our study objectives were to (1) determine if larval densities vary between littoral habitats (tidal slough vs. open-water shoal), (2) determine how larval densities in littoral habitats vary with physicochemical and biological attributes, (3) determine if larval densities vary between littoral habitats and long-term monitoring channel collections, and (4) determine what factors predict larval rearing distributions from the long-term monitoring channel collections. Larval densities did not vary between littoral habitats but they did vary between years. Water temperature, salinity, and chlorophyll a were found important in predicting larval densities in littoral habitats. Larval densities do not vary between littoral and channel surveys; however, the analysis based on channel data suggests that Longfin Smelt are hatching and rearing in a much broader region and under higher salinities (∼2–12 psu) than previously recognized. Results of this study indicate that conservation efforts should consider how freshwater flow, habitat, climate, and food webs interact as mechanisms that influence Longfin Smelt recruitment in estuarine environments.

  2. A new seamless, high-resolution digital elevation model of the San Francisco Bay-Delta Estuary, California

    Science.gov (United States)

    Fregoso, Theresa; Wang, Rueen-Fang; Ateljevich, Eli; Jaffe, Bruce E.

    2017-06-14

    Climate change, sea-level rise, and human development have contributed to the changing geomorphology of the San Francisco Bay - Delta (Bay-Delta) Estuary system. The need to predict scenarios of change led to the development of a new seamless, high-resolution digital elevation model (DEM) of the Bay – Delta that can be used by modelers attempting to understand potential future changes to the estuary system. This report details the three phases of the creation of this DEM. The first phase took a bathymetric-only DEM created in 2005 by the U.S. Geological Survey (USGS), refined it with additional data, and identified areas that would benefit from new surveys. The second phase began a USGS collaboration with the California Department of Water Resources (DWR) that updated a 2012 DWR seamless bathymetric/topographic DEM of the Bay-Delta with input from the USGS and modifications to fit the specific needs of USGS modelers. The third phase took the work from phase 2 and expanded the coverage area in the north to include the Yolo Bypass up to the Fremont Weir, the Sacramento River up to Knights Landing, and the American River up to the Nimbus Dam, and added back in the elevations for interior islands. The constant evolution of the Bay-Delta will require continuous updates to the DEM of the Delta, and there still are areas with older data that would benefit from modern surveys. As a result, DWR plans to continue updating the DEM.

  3. Climate change likely to facilitate the invasion of the non-native hydroid, Cordylophora caspia, in the San Francisco Estuary.

    Directory of Open Access Journals (Sweden)

    Mariah H Meek

    Full Text Available Climate change and invasive species can both have negative impacts on native species diversity. Additionally, climate change has the potential to favor invasive species over natives, dealing a double blow to native biodiversity. It is, therefore, vital to determine how changing climate conditions are directly linked to demographic rates and population growth of non-native species so we can quantitatively evaluate how invasive populations may be affected by changing conditions and, in turn, impact native species. Cordylophora caspia, a hydrozoan from the Ponto-Caspian region, has become established in the brackish water habitats of the San Francisco Estuary (SFE. We conducted laboratory experiments to study how temperature and salinity affect C. caspia population growth rates, in order to predict possible responses to climate change. C. Caspia population growth increased nonlinearly with temperature and leveled off at a maximum growth rate near the annual maximum temperature predicted under a conservative climate change scenario. Increasing salinity, however, did not influence growth rates. Our results indicate that C. caspia populations in the SFE will benefit from predicted regional warming trends and be little affected by changes in salinity. The population of C. caspia in the SFE has the potential to thrive under future climate conditions and may subsequently increase its negative impact on the food web.

  4. Sociodemographic Factors Associated With Trans*female Youth's Access to Health Care in the San Francisco Bay Area.

    Science.gov (United States)

    Johns, Elizabeth A; Jin, Harry; Auerswald, Colette L; Wilson, Erin C

    2017-08-01

    Trans*female youth (TFY) are an underserved population at risk for a variety of poor health outcomes, in part related to barriers to accessing health and mental health care. We conducted a secondary analysis of data collected with 250 TFY aged 16-24 years in the San Francisco Bay Area from 2012 to 2014. Logistic regression was used to test associations between sociodemographic variables and barriers to gender identity-based medical and mental health care. Having a history of unstable housing was associated with significantly higher odds of problems accessing both medical care (odds ratio: 2.16, 95% confidence interval: 1.12-4.13) and mental health care due to gender identity (odds ratio 2.65, 95% confidence interval: 1.08-6.45). Conversely, identifying as genderqueer/genderfluid, Latina, or living in dependent housing was associated with access to either medical or mental health care. Interventions are needed to address housing and discrimination barring access to health care among TFY. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  5. Trends in risk behavior and HIV seroprevalence in heterosexual injection drug users in San Francisco, 1986-1992.

    Science.gov (United States)

    Watters, J K

    1994-12-01

    We examine changes and stability in risk behaviors and HIV-1 seroprevalence among heterosexual injection drug users (IDUs) over 13 cross-sectional surveys, 1986-1992. Interviews (n = 5,956) were conducted with IDUs in street settings and drug detoxification clinics over 6.5 years, and respondents were tested for HIV-1 antibody. Trends in use of condoms and bleach and HIV seroprevalence were assessed using multiple logistic and linear regression analyses. The percentage of time condoms were reportedly used during intercourse among men increased from 4.5% to 31.0%. Among the declining population of IDUs who reported needle sharing, reported use of bleach increased from 3% to 89%. Significant changes in use of bleach 100% of the time were reported: 29.8% in 1988, 52.8% in 1990, and 40.0% in 1992. HIV seroprevalence doubled from 7% in 1986 to 14% in 1987. Post-1987 fluctuations in HIV seroprevalence were not significant. Significant changes in risk behaviors among IDUs were reported over the study period. These changes coincided with the implementation of HIV prevention in San Francisco, including outreach programs, HIV testing and counseling, bleach distribution, and syringe exchange. The moderate and stable rate of HIV seroprevalence beginning in 1987 parallels self-reported reductions in risk behavior.

  6. Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California

    Science.gov (United States)

    Wagner, David L.; Saucedo, George J.; Clahan, Kevin B.; Fleck, Robert J.; Langenheim, Victoria E.; McLaughlin, Robert J.; Sarna-Wojcicki, Andrei M.; Allen, James R.; Deino, Alan L.

    2011-01-01

    Recent geologic mapping in the northern San Francisco Bay region (California, USA) supported by radiometric dating and tephrochronologic correlations, provides insights into the framework geology, stratigraphy, tectonic evolution, and geologic history of this part of the San Andreas transform plate boundary. There are 25 new and existing radiometric dates that define three temporally distinct volcanic packages along the north margin of San Pablo Bay, i.e., the Burdell Mountain Volcanics (11.1 Ma), the Tolay Volcanics (ca. 10–8 Ma), and the Sonoma Volcanics (ca. 8–2.5 Ma). The Burdell Mountain and the Tolay Volcanics are allochthonous, having been displaced from the Quien Sabe Volcanics and the Berkeley Hills Volcanics, respectively. Two samples from a core of the Tolay Volcanics taken from the Murphy #1 well in the Petaluma oilfield yielded ages of 8.99 ± 0.06 and 9.13 ± 0.06 Ma, demonstrating that volcanic rocks exposed along Tolay Creek near Sears Point previously thought to be a separate unit, the Donnell Ranch volcanics, are part of the Tolay Volcanics. Other new dates reported herein show that volcanic rocks in the Meacham Hill area and extending southwest to the Burdell Mountain fault are also part of the Tolay Volcanics. In the Sonoma volcanic field, strongly bimodal volcanic sequences are intercalated with sediments. In the Mayacmas Mountains a belt of eruptive centers youngs to the north. The youngest of these volcanic centers at Sugarloaf Ridge, which lithologically, chemically, and temporally matches the Napa Valley eruptive center, was apparently displaced 30 km to the northwest by movement along the Carneros and West Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the Rodgers Creek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek–Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa basin in the Late Miocene and

  7. Ground-Water Quality Data in the San Francisco Bay Study Unit, 2007: Results from the California GAMA Program

    Science.gov (United States)

    Ray, Mary C.; Kulongoski, Justin T.; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 620-square-mile San Francisco Bay study unit (SFBAY) was investigated from April through June 2007 as part of the Priority Basin project of the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground-water quality, as well as a statistically consistent basis for comparing water quality throughout California. Samples in SFBAY were collected from 79 wells in San Francisco, San Mateo, Santa Clara, Alameda, and Contra Costa Counties. Forty-three of the wells sampled were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Thirty-six wells were sampled to aid in evaluation of specific water-quality issues (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, trace elements, chloride and bromide isotopes, and uranium and strontium isotopes), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14 isotopes, and stable isotopes of hydrogen, oxygen, nitrogen, boron, and carbon), and dissolved noble gases (noble gases were analyzed in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blank samples

  8. Organizing for intelligent transportation systems : case study of emergency operations in San Francisco Bay area

    Science.gov (United States)

    1997-01-01

    Computer-integrated transportation (CIT) is envisioned as an integrated network of public and private transportation organizations, each with unique responsibilities but working toward a common mission of facilitating travel across all modes of trans...

  9. CONFLICTO, IDENTIDAD Y SENTIDO: EL CASO DEL TAMPIERAZO DE SAN FRANCISCO (CÓRBOBA, 1973

    Directory of Open Access Journals (Sweden)

    Lucas Aimar

    2010-12-01

    Full Text Available Resumen El presente trabajo centra su atención sobre una de las protestas sociales más importantes de la historia de la provincia de Córdoba –ocurrida el 30 de julio de 1973 en la ciudad de San Francisco– conocida indistintamente como Tampierazo, Cordobacito o Sanfranciscazo. El hecho, que paralizó la ciudad y alcanzó momentos de extrema violencia, se inscribe en un amplio contexto de conflictividad social a nivel nacional y provincial; un ciclo de protestas –inaugurado con el Cordobazo– que se extendió hasta por lo menos 1975. Como proponemos, las acciones colectivas deben ser abordadas como un sistema de relaciones internas y externas y no como un simple punto de partida. Por ello, a partir de las redes de conflicto y los marcos de referencia existentes en el momento de la protesta, indagaremos el sentido que la acción tuvo para los actores intervinientes. Como intentaremos demostrar, el Tampierazo fue mucho más que un reclamo por los objetivos particulares de los obreros de la fábrica, convirtiéndose durante la jornada, en una amplia manifestación popular que canalizó el rechazo –compartido intersubjetivamente por varios sectores de la población– a las formas de control y los manejos que se mantenían desde los sectores dominantes del poder local.

  10. Mudflat morphodynamics and the impact of sea level rise in South San Francisco Bay

    Science.gov (United States)

    Van der Wegen, Mick; Jaffe, Bruce E.; Foxgrover, Amy; Roelvink, Dano

    2017-01-01

    Estuarine tidal mudflats form unique habitats and maintain valuable ecosystems. Historic measurements of a mudflat in San Fancsico Bay over the past 150 years suggest the development of a rather stable mudflat profile. This raises questions on its origin and governing processes as well as on the mudflats’ fate under scenarios of sea level rise and decreasing sediment supply. We developed a 1D morphodynamic profile model (Delft3D) that is able to reproduce the 2011 measured mudflat profile. The main, schematised, forcings of the model are a constant tidal cycle and constant wave action. The model shows that wave action suspends sediment that is transported landward during flood. A depositional front moves landward until landward bed levels are high enough to carry an equal amount of sediment back during ebb. This implies that, similar to observations, the critical shear stress for erosion is regularly exceeded during the tidal cycle and that modelled equilibrium conditions include high suspended sediment concentrations at the mudflat. Shear stresses are highest during low water, while shear stresses are lower than critical (and highest at the landward end) along the mudflat during high water. Scenarios of sea level rise and decreasing sediment supply drown the mudflat. In addition, the mudflat becomes more prone to channel incision because landward accumulation is hampered. This research suggests that sea level rise is a serious threat to the presence of many estuarine intertidal mudflats, adjacent salt marshes and their associated ecological values.

  11. High-resolution foraminiferal, isotopic, and trace element records from holocene estuarine deposits of San Francisco Bay, California

    Science.gov (United States)

    McGann, M.

    2008-01-01

    A 3.5-m gravity core (DJ6-93SF-6) from San Francisco Bay reveals a complex paleoclimatic history of the region over the last 3870 cal YBP. A polynomial equation based on 11 AMS 14C ages provides an excellent age model for the core, and environmental proxies for water temperature and salinity are derived from various foraminiferal abundances, stable carbon and oxygen isotopes, and Mg/Ca ratios. Two foraminiferal associations were identified by Q-mode cluster analysis: a colder-water Elphidium excavatum association and the warmer-water Ammonia beccarii-Elphidium gunteri association. The E. excavatum association dominates the core for all but about 600 years out of the last four millennia. At 3870 cal YBP, water temperatures were warm (13.9??C) and freshwater inflow was reduced compared with today. From 3590 to 2860 cal YBP, temperatures dropped 0.5??C and the climate remained dry. This was followed by a period of pronounced lower ??13C values, indicating that conditions became considerably wetter from 2860 to 2170 cal YBP. During this interval, the temperature oscillated frequently, peaking at 13.9??C at 2710 cal YBP, then dropping shortly thereafter to 12.8??C at 2420 cal YBP. Freshwater inflow gradually decreased between 2170 and 1950 cal YBP with a minimal rise in temperature, then changed quickly to colder and wetter conditions at 1900 cal YBP. Drier conditions then prevailed until 1480 cal YBP with water temperatures fluctuating between 13.1??C and 13.8??C, followed by wetter climate from 1480 to 1320 cal YBP. A significant faunal shift from the E. excavatum association to the A. beccarii-E. gunteri association occurred from 1250 to 650 cal YBP, possibly due to regional warming, decreased oxygen availability, and/or a change in the phyto-plankton community. Associated with this change in faunal composition were warm and dry conditions, representative of the Medieval Warm Period (Medieval Climatic Anomaly). A climatic shift coincident with the onset of the Little

  12. How can climate change and engineered water conveyance affect sediment dynamics in the San Francisco Bay-Delta system?

    Science.gov (United States)

    Achete, Fernanda; Van der Wegen, Mick; Roelvink, Jan Adriaan; Jaffe, Bruce E.

    2017-01-01

    Suspended sediment concentration is an important estuarine health indicator. Estuarine ecosystems rely on the maintenance of habitat conditions, which are changing due to direct human impact and climate change. This study aims to evaluate the impact of climate change relative to engineering measures on estuarine fine sediment dynamics and sediment budgets. We use the highly engineered San Francisco Bay-Delta system as a case study. We apply a process-based modeling approach (Delft3D-FM) to assess the changes in hydrodynamics and sediment dynamics resulting from climate change and engineering scenarios. The scenarios consider a direct human impact (shift in water pumping location), climate change (sea level rise and suspended sediment concentration decrease), and abrupt disasters (island flooding, possibly as the results of an earthquake). Levee failure has the largest impact on the hydrodynamics of the system. Reduction in sediment input from the watershed has the greatest impact on turbidity levels, which are key to primary production and define habitat conditions for endemic species. Sea level rise leads to more sediment suspension and a net sediment export if little room for accommodation is left in the system due to continuous engineering works. Mitigation measures like levee reinforcement are effective for addressing direct human impacts, but less effective for a persistent, widespread, and increasing threat like sea level rise. Progressive adaptive mitigation measures to the changes in sediment and flow dynamics resulting from sea level rise may be a more effective strategy. Our approach shows that a validated process-based model is a useful tool to address long-term (decades to centuries) changes in sediment dynamics in highly engineered estuarine systems. In addition, our modeling approach provides a useful basis for long-term, process-based studies addressing ecosystem dynamics and health.

  13. Predictors of incident herpes simplex virus type 2 infections in young women at risk for unintended pregnancy in San Francisco

    Directory of Open Access Journals (Sweden)

    Padian Nancy

    2007-09-01

    Full Text Available Abstract Background Young women receiving family planning services are at risk for both unintended pregnancy and herpes simplex virus type 2 (HSV-2 infection. Methods We performed a secondary analysis using data from a previously published randomized controlled trial evaluating access to emergency contraception on reproductive health outcomes. Women aged 15 to 24 years were recruited from two Planned Parenthood clinics and two community health clinics in San Francisco. Demographic information and sexual history were obtained by interview. HSV-2 seropositivity was determined by fingerstick blood test. New pregnancies were measured by self-report, urine testing and medical chart review. Subjects were evaluated for incident HSV-2 infection and pregnancy at a 6-month follow-up appointment. Women who were pregnant or intending to become pregnant at enrolment were excluded. Results At enrolment 2,104 women were screened for HSV-2 and 170 (8.1% were seropositive. Eighty-seven percent of initially seronegative women completed the study (n = 1,672 and 73 (4.4% became HSV-2 seropositive. HSV-2 seroincidence was 7.8 cases per 100 person-years. One hundred and seventeen women (7% became pregnant and 7 (6% of these had a seroincident HSV-2 infection during the study. After adjustment for confounders, predictors of incident HSV-2 infection were African American race and having multiple partners in the last six months. Condom use at last sexual encounter was protective. Conclusion HSV-2 seroincidence and the unintended pregnancy rate in young women were high. Providers who counsel women on contraceptive services and sexually transmitted infection prevention could play an expanded role in counselling women about HSV-2 prevention given the potential sequelae in pregnancy. The potential benefit of targeted screening and future vaccination against HSV-2 needs to be assessed in this population.

  14. A Trial of the Efficacy and Cost of Water Delivery Systems in San Francisco Bay Area Middle Schools, 2013.

    Science.gov (United States)

    Patel, Anisha I; Grummon, Anna H; Hampton, Karla E; Oliva, Ariana; McCulloch, Charles E; Brindis, Claire D

    2016-07-07

    US legislation requires that schools offer free drinking water where meals are served. However, little information is available about what types of water delivery systems schools should install to meet such requirements. The study objective was to examine the efficacy and cost of 2 water delivery systems (water dispensers and bottleless water coolers) in increasing students' lunchtime intake of water in low-income middle schools. In 2013, twelve middle schools in the San Francisco Bay Area participated in a cluster randomized controlled trial in which they received 6 weeks of promotional activities, received provision of cups, and were assigned to 1 of 2 cafeteria water delivery systems: water dispensers or bottleless water coolers (or schools served as a control). Student surveys (n = 595) and observations examined the interventions' effect on students' beverage intake and staff surveys and public data assessed intervention cost. Analysis occurred from 2013 through 2015. Mixed-effects logistic regression, accounting for clustering and adjustment for student sociodemographic characteristics, demonstrated a significant increase in the odds of students drinking water in schools with promotion plus water dispensers and cups (adjusted odds ratio = 3.1; 95% confidence interval, 1.4-6.7; P = .004) compared with schools with traditional drinking fountains and no cups or promotion. The cost of dispenser and bottleless water cooler programs was similar ($0.04 per student per day). Instead of relying on traditional drinking fountains, schools should consider installing water sources, such as plastic dispensers with cups, as a low-cost, effective means for increasing students' water intake.

  15. Iglesia y participación comunitaria en salud: el caso del Municipio San Francisco del estado Zulia, Venezuela

    Directory of Open Access Journals (Sweden)

    José Guillermo García

    2002-01-01

    Full Text Available Este trabajo tiene por objeto identificar en forma comparada los factores que condicionan la participación de las comunidades Betulio González y 24 de Julio del municipio San Francisco del estado Zulia en el subprograma de Medicina Natural que promociona la Iglesia Católica. Bajo un esquema conceptual que combina principios de las teorías: Elección Racional, Movilización de Recursos, Privación Relativa, Identidades Colectivas y Capital Social, se plantea la hipótesis que la participación de dichas comunidades en el subprograma está determinada por una serie de factores internos y externos en donde resaltan la representación social que tienen del subprograma, el cálculo racional de la acción, la tradición participativa y el apoyo organizativo de grupos voluntarios. Se empleó la perspectiva etnomedotológica en la realización de entrevistas en profundidad, de donde se extrajo como conclusión que existen factores comunes que condicionan la participación en ambas comunidades, tales como la reafirmación de una identidad femenina entendida como un incentivo para la acción, una representación colectiva positiva sobre la medicina natural y la presencia de recursos organizativos externos proporcionados por las escuelas ubicadas en cada comunidad, por grupos eclesiales de base y por la misma Iglesia Católica como agente promotor del subprograma.

  16. Gender differences in sexual and injection risk behavior among active young injection drug users in San Francisco (the UFO Study).

    Science.gov (United States)

    Evans, Jennifer L; Hahn, Judith A; Page-Shafer, Kimberly; Lum, Paula J; Stein, Ellen S; Davidson, Peter J; Moss, Andrew R

    2003-03-01

    Female injection drug users (IDUs) represent a large proportion of persons infected with HIV in the United States, and women who inject drugs have a high incidence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. Therefore, it is important to understand the role of gender in injection risk behavior and the transmission of blood-borne virus. In 2000-2002, 844 young (<30 years old) IDUs were surveyed in San Francisco. We compared self-reported risk behavior between 584 males and 260 female participants from cross-sectional baseline data. We used logistic regression to determine whether demographic, structural, and relationship variables explained increased needle borrowing, drug preparation equipment sharing, and being injected by another IDU among females compared to males. Females were significantly younger than males and were more likely to engage in needle borrowing, ancillary equipment sharing, and being injected by someone else. Females were more likely than males to report recent sexual intercourse and to have IDU sex partners. Females and males were not different with respect to education, race/ethnicity, or housing status. In logistic regression models for borrowing a used needle and sharing drug preparation equipment, increased risk in females was explained by having an injection partner who was also a sexual partner. Injecting risk was greater in the young female compared to male IDUs despite equivalent frequency of injecting. Overlapping sexual and injection partnerships were a key factor in explaining increased injection risk in females. Females were more likely to be injected by another IDU even after adjusting for years injecting, being in a relationship with another IDU, and other potential confounders. Interventions to reduce sexual and injection practices that put women at risk of contracting hepatitis and HIV are needed.

  17. Trends in methamphetamine use in young injection drug users in San Francisco from 1998 to 2004: the UFO Study.

    Science.gov (United States)

    Inglez-Dias, Aline; Hahn, Judith A; Lum, Paula J; Evans, Jennifer; Davidson, Peter; Page-Shafer, Kimberly

    2008-05-01

    To describe temporal trends in methamphetamine use among young injection drug users (IDU) in San Francisco. Secondary analysis of cross-sectional baseline data collected for a longitudinal study of young IDU from 1998 to 2004. Participants were 1445 young IDU (<30 years old) who reported injection in the previous month, English-speaking, and recruited by street outreach methods. We examined trends for: lifetime (ever) and recent (30-day) methamphetamine use, including injected and non-injected, and by age group and sexual risk behaviour [men who have sex with men injecting drug users (MSM-IDU), male IDU (non-MSM) and female IDU]. In 1998, 1999, 2000, 2001, 2003 and 2004 we interviewed 237, 276, 431, 310, 147 and 44 participants, respectively. Overall, median age was 22 years [interquartile range (IQR) 20-25], 30.3% were women and median duration of injecting was 4.4 years (IQR 2-7). Prevalence of methamphetamine use was high, with 50.1% reporting recent injection, but overall there were no temporal increases in reported 'ever' injected use. Recent methamphetamine injection (past 30 days) increased significantly, and peaked at 60% in 2003. MSM-IDU had higher methamphetamine injection ever (92.3%) and recently (59.5%) compared to heterosexual male (non-MSM) IDU (81.6% and 47.3%, respectively) and to female IDU (78.4% and 46.1%, respectively). Despite reports of ubiquitous increases in methamphetamine use, there were no significant increases in 6 years in ever injecting methamphetamine overall among young IDU. MSM-IDU who reported the highest methamphetamine use overall reported some increases in recent injected use. The methamphetamine 'epidemic' was probably under way among young IDU earlier than other populations.

  18. Projected evolution of California's San Francisco bay-delta-river system in a century of climate change

    Science.gov (United States)

    Cloern, J.E.; Knowles, N.; Brown, L.R.; Cayan, D.; Dettinger, M.D.; Morgan, T.L.; Schoellhamer, D.H.; Stacey, M.T.; van der Wegen, M.; Wagner, R.W.; Jassby, A.D.

    2011-01-01

    Background: Accumulating evidence shows that the planet is warming as a response to human emissions of greenhouse gases. Strategies of adaptation to climate change will require quantitative projections of how altered regional patterns of temperature, precipitation and sea level could cascade to provoke local impacts such as modified water supplies, increasing risks of coastal flooding, and growing challenges to sustainability of native species. Methodology/Principal Findings: We linked a series of models to investigate responses of California's San Francisco Estuary-Watershed (SFEW) system to two contrasting scenarios of climate change. Model outputs for scenarios of fast and moderate warming are presented as 2010-2099 projections of nine indicators of changing climate, hydrology and habitat quality. Trends of these indicators measure rates of: increasing air and water temperatures, salinity and sea level; decreasing precipitation, runoff, snowmelt contribution to runoff, and suspended sediment concentrations; and increasing frequency of extreme environmental conditions such as water temperatures and sea level beyond the ranges of historical observations. Conclusions/Significance: Most of these environmental indicators change substantially over the 21st century, and many would present challenges to natural and managed systems. Adaptations to these changes will require flexible planning to cope with growing risks to humans and the challenges of meeting demands for fresh water and sustaining native biota. Programs of ecosystem rehabilitation and biodiversity conservation in coastal landscapes will be most likely to meet their objectives if they are designed from considerations that include: (1) an integrated perspective that river-estuary systems are influenced by effects of climate change operating on both watersheds and oceans; (2) varying sensitivity among environmental indicators to the uncertainty of future climates; (3) inevitability of biological community

  19. Projected evolution of California's San Francisco Bay-Delta-river system in a century of climate change.

    Directory of Open Access Journals (Sweden)

    James E Cloern

    Full Text Available BACKGROUND: Accumulating evidence shows that the planet is warming as a response to human emissions of greenhouse gases. Strategies of adaptation to climate change will require quantitative projections of how altered regional patterns of temperature, precipitation and sea level could cascade to provoke local impacts such as modified water supplies, increasing risks of coastal flooding, and growing challenges to sustainability of native species. METHODOLOGY/PRINCIPAL FINDINGS: We linked a series of models to investigate responses of California's San Francisco Estuary-Watershed (SFEW system to two contrasting scenarios of climate change. Model outputs for scenarios of fast and moderate warming are presented as 2010-2099 projections of nine indicators of changing climate, hydrology and habitat quality. Trends of these indicators measure rates of: increasing air and water temperatures, salinity and sea level; decreasing precipitation, runoff, snowmelt contribution to runoff, and suspended sediment concentrations; and increasing frequency of extreme environmental conditions such as water temperatures and sea level beyond the ranges of historical observations. CONCLUSIONS/SIGNIFICANCE: Most of these environmental indicators change substantially over the 21(st century, and many would present challenges to natural and managed systems. Adaptations to these changes will require flexible planning to cope with growing risks to humans and the challenges of meeting demands for fresh water and sustaining native biota. Programs of ecosystem rehabilitation and biodiversity conservation in coastal landscapes will be most likely to meet their objectives if they are designed from considerations that include: (1 an integrated perspective that river-estuary systems are influenced by effects of climate change operating on both watersheds and oceans; (2 varying sensitivity among environmental indicators to the uncertainty of future climates; (3 inevitability of

  20. Dietary flexibility in three representative waterbirds across salinity and depth gradients in salt ponds of San Francisco Bay

    Science.gov (United States)

    Takekawa, John Y.; Miles, A.K.; Tsao-Melcer, D. C.; Schoellhamer, D.H.; Fregien, S.; Athearn, N.D.

    2009-01-01

    Salt evaporation ponds have existed in San Francisco Bay, California, for more than a century. In the past decade, most of the salt ponds have been retired from production and purchased for resource conservation with a focus on tidal marsh restoration. However, large numbers of waterbirds are found in salt ponds, especially during migration and wintering periods. The value of these hypersaline wetlands for waterbirds is not well understood, including how different avian foraging guilds use invertebrate prey resources at different salinities and depths. The aim of this study was to investigate the dietary flexibility of waterbirds by examining the population number and diet of three feeding guilds across a salinity and depth gradient in former salt ponds of the Napa-Sonoma Marshes. Although total invertebrate biomass and species richness were greater in low than high salinity salt ponds, waterbirds fed in ponds that ranged from low (20 g l-1) to very high salinities (250 g l -1). American avocets (surface sweeper) foraged in shallow areas at pond edges and consumed a wide range of prey types (8) including seeds at low salinity, but preferred brine flies at mid salinity (40-80 g l-1). Western sandpipers (prober) focused on exposed edges and shoal habitats and consumed only a few prey types (2-4) at both low and mid salinities. Suitable depths for foraging were greatest for ruddy ducks (diving benthivore) that consumed a wide variety of invertebrate taxa (5) at low salinity, but focused on fewer prey (3) at mid salinity. We found few brine shrimp, common in higher salinity waters, in the digestive tracts of any of these species. Dietary flexibility allows different guilds to use ponds across a range of salinities, but their foraging extent is limited by available water depths. ?? 2009 USGS, US Government.

  1. Obesity and survival in population-based patients with pancreatic cancer in the San Francisco Bay Area.

    Science.gov (United States)

    Gong, Zhihong; Holly, Elizabeth A; Bracci, Paige M

    2012-12-01

    Obesity has been consistently associated with increased risk of pancreatic cancer incidence and mortality. However, studies of obesity and overall survival in patients with pancreatic cancer are notably lacking, especially in population-based studies. Active and passive follow-up were used to determine vital status and survival for 510 pancreatic cancer patients diagnosed from 1995 to 1999 in a large population-based case-control study in the San Francisco Bay Area. Survival rates were computed using Kaplan-Meier methods. Hazard ratios (HR) and 95 % confidence intervals (CI) were estimated in multivariable Cox proportional hazards models as measures of the association between pre-diagnostic obesity and pancreatic cancer survival. An elevated hazard ratio of 1.3 (95 % CI, 0.91-1.81) was observed for obese [body mass index (BMI) ≥ 30] compared with normal range BMI (patients. Associations between BMI and overall survival did not statistically significantly vary by known prognostic and risk factors (all p-interaction ≥0.18), yet elevated HRs consistently were observed for obese compared with normal BMI patients [localized disease at diagnosis (HR, 3.1), surgical resection (HR, 1.6), ever smokers (HR, 1.6), diabetics (HR, 3.3)]. Poor survival was observed among men, older patients, more recent and current smokers, whereas improved survival was observed for Asian/Pacific Islanders. Our results in general provide limited support for an association between pre-diagnostic obesity and decreased survival in patients with pancreatic cancer. Patterns of reduced survival associated with obesity in some patient subgroups could be due to chance and require assessment in larger pooled studies.

  2. Projected evolution of California's San Francisco Bay-Delta-river system in a century of climate change.

    Science.gov (United States)

    Cloern, James E; Knowles, Noah; Brown, Larry R; Cayan, Daniel; Dettinger, Michael D; Morgan, Tara L; Schoellhamer, David H; Stacey, Mark T; van der Wegen, Mick; Wagner, R Wayne; Jassby, Alan D

    2011-01-01

    Accumulating evidence shows that the planet is warming as a response to human emissions of greenhouse gases. Strategies of adaptation to climate change will require quantitative projections of how altered regional patterns of temperature, precipitation and sea level could cascade to provoke local impacts such as modified water supplies, increasing risks of coastal flooding, and growing challenges to sustainability of native species. We linked a series of models to investigate responses of California's San Francisco Estuary-Watershed (SFEW) system to two contrasting scenarios of climate change. Model outputs for scenarios of fast and moderate warming are presented as 2010-2099 projections of nine indicators of changing climate, hydrology and habitat quality. Trends of these indicators measure rates of: increasing air and water temperatures, salinity and sea level; decreasing precipitation, runoff, snowmelt contribution to runoff, and suspended sediment concentrations; and increasing frequency of extreme environmental conditions such as water temperatures and sea level beyond the ranges of historical observations. Most of these environmental indicators change substantially over the 21(st) century, and many would present challenges to natural and managed systems. Adaptations to these changes will require flexible planning to cope with growing risks to humans and the challenges of meeting demands for fresh water and sustaining native biota. Programs of ecosystem rehabilitation and biodiversity conservation in coastal landscapes will be most likely to meet their objectives if they are designed from considerations that include: (1) an integrated perspective that river-estuary systems are influenced by effects of climate change operating on both watersheds and oceans; (2) varying sensitivity among environmental indicators to the uncertainty of future climates; (3) inevitability of biological community changes as responses to cumulative effects of climate change and other

  3. Projected evolution of California's San Francisco Bay-Delta-River System in a century of continuing climate change

    Science.gov (United States)

    Cloern, James E.; Knowles, Noah; Brown, Larry R.; Cayan, Daniel; Dettinger, Michael D.; Morgan, Tara L.; Schoellhamer, David H.; Stacey, Mark T.; van der Wegen, Mick; Wagner, R. Wayne; Jassby, Alan D.

    2011-01-01

    Background Accumulating evidence shows that the planet is warming as a response to human emissions of greenhouse gases. Strategies of adaptation to climate change will require quantitative projections of how altered regional patterns of temperature, precipitation and sea level could cascade to provoke local impacts such as modified water supplies, increasing risks of coastal flooding, and growing challenges to sustainability of native species. Methodology/Principal Findings We linked a series of models to investigate responses of California's San Francisco Estuary-Watershed (SFEW) system to two contrasting scenarios of climate change. Model outputs for scenarios of fast and moderate warming are presented as 2010–2099 projections of nine indicators of changing climate, hydrology and habitat quality. Trends of these indicators measure rates of: increasing air and water temperatures, salinity and sea level; decreasing precipitation, runoff, snowmelt contribution to runoff, and suspended sediment concentrations; and increasing frequency of extreme environmental conditions such as water temperatures and sea level beyond the ranges of historical observations. Conclusions/Significance Most of these environmental indicators change substantially over the 21st century, and many would present challenges to natural and managed systems. Adaptations to these changes will require flexible planning to cope with growing risks to humans and the challenges of meeting demands for fresh water and sustaining native biota. Programs of ecosystem rehabilitation and biodiversity conservation in coastal landscapes will be most likely to meet their objectives if they are designed from considerations that include: (1) an integrated perspective that river-estuary systems are influenced by effects of climate change operating on both watersheds and oceans; (2) varying sensitivity among environmental indicators to the uncertainty of future climates; (3) inevitability of biological community

  4. Trajectory of early tidal marsh restoration: elevation, sedimentation and colonization of breached salt ponds in the northern San Francisco Bay

    Science.gov (United States)

    Brand, L. Arriana; Smith, Lacy M.; Takekawa, John Y.; Athearn, Nicole D.; Taylor, Karen; Shellenbarger, Gregory; Schoellhamer, David H.; Spenst, Renee

    2012-01-01

    Tidal marsh restoration projects that cover large areas are critical for maintaining target species, yet few large sites have been studied and their restoration trajectories remain uncertain. A tidal marsh restoration project in the northern San Francisco Bay consisting of three breached salt ponds (≥300 ha each; 1175 ha total) is one of the largest on the west coast of North America. These diked sites were subsided and required extensive sedimentation for vegetation colonization, yet it was unclear whether they would accrete sediment and vegetate within a reasonable timeframe. We conducted bathymetric surveys to map substrate elevations using digital elevation models and surveyed colonizing Pacific cordgrass (Spartina foliosa). The average elevation of Pond 3 was 0.96 ± 0.19 m (mean ± SD; meters NAVD88) in 2005. In 2008–2009, average pond elevations were 1.05 ± 0.25 m in Pond 3, 0.81 ± 0.26 m in Pond 4, and 0.84 ± 0.24 m in Pond 5 (means ± SD; meters NAVD88). The largest site (Pond 3; 508 ha) accreted 9.5 ± 0.2 cm (mean ± SD) over 4 years, but accretion varied spatially and ranged from sediment loss in borrow ditches and adjacent to an unplanned, early breach to sediment gains up to 33 cm in more sheltered regions. The mean elevation of colonizing S. foliosa varied by pond (F = 71.20, df = 84, P S. foliosa. Our results suggest that sedimentation to elevations that enable vegetation colonization is feasible in large sites with sufficient sediment loads although may occur more slowly compared with smaller sites.

  5. Capital Social y gestión de demandas ciudadanas en el Municipio San Francisco. Estado Zulia

    Directory of Open Access Journals (Sweden)

    Héctor Govea Hernández

    2009-01-01

    Full Text Available El presente artículo tiene como propósito el análisis de los elementos del capital social que se encuentran presentes en la gestión de demandas ciudadanas de las asociaciones de vecinos a la Alcaldía del Municipio San Francisco del Estado Zulia.Alos fines, se concretó un estudio de campo, descriptivo-analítico. El referente empírico fueron 20 Asociaciones de vecinos distribuidas en las parroquias que lo conforman. El instrumento utilizado consistió en un cuestionario tipo estándar; se hace énfasis en la observación directa o participante, las entrevistas abiertas, y el análisis de documentos proporcionados por los informantes clave. Los hallazgos dan cuenta de: a El Capital Social de las asociaciones de vecinos del municipio, se distingue por ser medianamente positivo, pero enfrenta serias amenazas. b La confianza y los valores éticos, se encuentran orientados hacia la baja y atentan contra la acción social y gestión de demandas de las asociaciones de vecinos; c la participación como dimensión del capital social es restringida, limitada solo al voto; por lo que deslegitima la acción del gobierno local. Todo lo anterior refleja desconfianza hacia este tipo de organizaciones. e Se percibe un espacio muy limitado para la construcción de ciudadanía y la generación de mecanismos de empoderamiento ciudadano, f Se registra una inconsistencia entre el discurso, la acción y los resultados de la gestión gubernamental. Se concluye que estos rasgos se constituyen en una barrera para la legitimidad y gobernabilidad del gobierno local en cuestión.

  6. The burden of liver cancer in Asians and Pacific Islanders in the Greater San Francisco Bay Area, 1990 through 2004.

    Science.gov (United States)

    Chang, Ellen T; Keegan, Theresa H M; Gomez, Scarlett L; Le, Gem M; Clarke, Christina A; So, Samuel K S; Glaser, Sally L

    2007-05-15

    To the authors' knowledge, no previous U.S. study has examined time trends in the incidence rate of liver cancer in the high-risk Asian/Pacific Islander population. In this study, liver cancer incidence trends were evaluated in Chinese, Filipino, Japanese, Korean, and Vietnamese men and women in the Greater San Francisco Bay Area of California between 1990 and 2004. Populations at risk were estimated by using the cohort-component demographic method. Annual percentage changes (APCs) in age-adjusted incidence rates of primary liver cancer among Asians/Pacific Islanders in the Greater Bay Area Cancer Registry were calculated by using joinpoint regression analysis. The incidence rate of liver cancer between 1990 and 2004 did not change significantly in Asian/Pacific Islander men or women overall. However, the incidence rate declined, although the decline was not statistically significant, among Chinese men (APC, -1.6%; 95% confidence interval [95% CI], -3.4-0.3%), Japanese men (APC, -4.9%; 95% CI, -10.7-1.2%), and Japanese women (APC, -3.6%; 95% CI, -8.9-2%). Incidence rates remained consistently high for Vietnamese, Korean, and Filipino men and women. Trends in the incidence rate of hepatocellular carcinoma were comparable to those for liver cancer. Although disparities in liver cancer incidence between Asians/Pacific Islanders and other racial/ethnic groups diminished between the period from 1990 through 1994 and the period from 2000 through 2004, the disparities among Asian subgroups increased. Liver cancer continues to affect Asian/Pacific Islander Americans disproportionately, with consistently high incidence rates in most subgroups. Culturally targeted prevention methods are needed to reduce the high rates of liver cancer in this growing population in the U.S. (c) 2007 American Cancer Society

  7. Concordance of risk behavior reporting within HCV serodiscordant injecting partnerships of young injection drug users in San Francisco, CA.

    Science.gov (United States)

    Evans, Jennifer L; Morris, Meghan D; Yu, Michelle; Page, Kimberly; Hahn, Judith A

    2014-09-01

    Young injection drug users (IDU, under age 30) often inject with other IDU, creating an environment for risk of blood-borne disease transmission through sharing of needles and drug preparation equipment. Epidemiologic studies rely on self reported injection behavior data for measures of transmission risk, therefore we sought to quantify the degree of concordance of reported injecting risk behaviors between injecting dyads. From May, 2006 through 2013 we enrolled 72 injecting dyads in San Francisco, California, who were hepatitis C virus (HCV) RNA discordant. Each partnership was followed prospectively for up to six months. Monthly interviews from each partner were date-matched and responses to relationship characteristics and risk behavior questions were compared. Concordance of reporting was estimated with the concordance correlation coefficient for longitudinal data (CCC) and the prevalence adjusted bias adjusted kappa (PABAK). Participants had a median age of 26 (IQR: 23, 28) years and median years injecting of 7.0 (IQR: 3.0, 10.6). Thirty-eight percent of the injecting dyads were also sexual partners. Concordance levels were highest for partnership characteristics, such as length of acquaintance, number of days cohabitating, and sexual intercourse in the past month (CCC=0.95; 0.82, and 0.90, respectively). Shared injection risk behaviors such as injecting with the HCV+ partner's previously used syringe and using contaminated injection preparation equipment had slight to fair agreement (CCC=0.22; 0.23; PABAK=0.43, 0.36, respectively). Concordance levels ranged from low to high. Potential sources of measurement error for low agreement items include recall and social-desirability biases and question interpretation. Published by Elsevier Ireland Ltd.

  8. Geologic Investigations Spurred by Analog Testing at the 7504 Cone-SP Mountain Area of the San Francisco Volcanic Field

    Science.gov (United States)

    Eppler, Dean B.

    2015-01-01

    The SP Mountain area of the San Francisco Volcanic Field, AZ, has been used as an analog mission development site for NASA since 1998. This area consists of basaltic cinder cones, lava flows and maar craters that have been active since mid-Miocene, with the youngest events occurring within the last 10,000 years. The area has been used because its geologic and topographic resemblance to lunar and Martian terrains provides an ideal venue for testing hardware and science operations practices that might be employed on planetary surfaces, as well as training astronauts in field geology. Analog operations have often led to insights that spurred new scientific investigations. Most recently, an investigation of the 7504 cone was initiated due to perceptions that Apollo-style traverse plans executed during the Desert RATS 2010 mission had characterized the area incorrectly, leading to concerns that the Apollo traverse planning process was scientifically flawed. This investigation revealed a complex history of fissure eruptions of lava and cinders, cinder cone development, a cone-fill-and-spill episode, extensive rheomorphic lava flow initiation and emplacement, and cone sector collapse that led to a final lava flow. This history was not discernible on pre-RATS mission photogeology, although independent analysis of RATS 2010 data and samples develped a "75% complete solution" that validated the pre-RATS mission planning and Apollo traverse planning and execution. The study also pointed out that the development of scientific knowledge with time in a given field area is not linear, but may follow a functional form that rises steeply in the early period of an investigation but flattens out in the later period, asymptotically approaching a theoretical "complete knowledge" point that probably cannot be achieved. This implies that future human missions must be prepared to shift geographic areas of investigation regularly if significant science returns are to be forthcoming.

  9. Connecting Past to Present and Watersheds to Ocean: Modeling 165 Years of Incremental Changes to Flows into the San Francisco Bay Delta System

    Science.gov (United States)

    MacVean, L. J.; Thompson, S. E.; Huttom, P. H.; Sivapalan, M.

    2016-02-01

    California's Sacramento-San Joaquin Delta sits at the intersection of vast agricultural and population centers, and supplies fresh water for the diverse and often competing needs of ecosystems, farmers, and millions of Californians. Managing and allocating this resource is a complex feat of economics, politics, and engineering, made increasingly contentious by the ongoing drought. The objective of this research is to augment the scientific foundation of management decisions by addressing the question of how flows into the Delta have evolved in response to human intervention since 1850. In particular, quantifying the dynamic components of water usage through vegetative uptake and evapotranspiration, groundwater recharge, flood conveyance, and water exports at incremental levels of development is a key ambition. This approach emphasizes the built environment, which is subject to the local regulatory framework, rather than climate change, which is generally considered immovable without united global effort. This work encompasses the creation of a hydrologic model representing the watersheds of the San Francisco Bay-Delta system, and quantifies the impacts of changes in land use and the gradual construction of levees, reservoirs, and diversion infrastructure. The model is run using the same climatological forcing at each level of development, thus elucidating the effects of local anthropogenic activity on the Delta and the inflows to the San Francisco Bay estuary. Our results provide a timeline of change, giving decision-makers a scientifically established baseline to aid in the sustainable management of the Bay-Delta system.

  10. The Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California

    Science.gov (United States)

    Jachens, Robert C.; Wentworth, Carl M.; Graymer, Russell W.; Williams, Robert; Ponce, David A.; Mankinen, Edward A.; Stephenson, William J.; Langenheim, Victoria

    2017-01-01

    The Evergreen basin is a 40-km-long, 8-km-wide Cenozoic sedimentary basin that lies mostly concealed beneath the northeastern margin of the Santa Clara Valley near the south end of San Francisco Bay (California, USA). The basin is bounded on the northeast by the strike-slip Hayward fault and an approximately parallel subsurface fault that is structurally overlain by a set of west-verging reverse-oblique faults which form the present-day southeastward extension of the Hayward fault. It is bounded on the southwest by the Silver Creek fault, a largely dormant or abandoned fault that splays from the active southern Calaveras fault. We propose that the Evergreen basin formed as a strike-slip pull-apart basin in the right step from the Silver Creek fault to the Hayward fault during a time when the Silver Creek fault served as a segment of the main route by which slip was transferred from the central California San Andreas fault to the Hayward and other East Bay faults. The dimensions and shape of the Evergreen basin, together with palinspastic reconstructions of geologic and geophysical features surrounding it, suggest that during its lifetime, the Silver Creek fault transferred a significant portion of the ∼100 km of total offset accommodated by the Hayward fault, and of the 175 km of total San Andreas system offset thought to have been accommodated by the entire East Bay fault system. As shown previously, at ca. 1.5–2.5 Ma the Hayward-Calaveras connection changed from a right-step, releasing regime to a left-step, restraining regime, with the consequent effective abandonment of the Silver Creek fault. This reorganization was, perhaps, preceded by development of the previously proposed basin-bisecting Mount Misery fault, a fault that directly linked the southern end of the Hayward fault with the southern Calaveras fault during extinction of pull-apart activity. Historic seismicity indicates that slip below a depth of 5 km is mostly transferred from the Calaveras

  11. Estudio descriptivo de las prácticas de manufactura en la industria panelera de los trapiches San Francisco y La Esmeralda en Boyacá y Caldas.

    OpenAIRE

    Corrales Ramírez, Lucía Constanza; Muñoz Ariza, Maira María; González Pérez, Lina María

    2012-01-01

    El objetivo de este proyecto fue evaluar la aplicación de las prácticas de manufactura en los trapiches San Francisco y La Esmeralda mediante la aplicación de encuestas etnográficas, documentación fotográfica e identificación de contaminantes microbiológicos presentes en la panela, manos de empleados e implementos de trabajo. En los resultados obtenidos se encontró que una proporción importante de las muestras presentaron contaminación por bacterias como Staphylococcus epidermidis, Streptococ...

  12. Prime Contract Awards Alphabetically by Contractor, State or Country, and Place. Part 13 (NCR Media Products Division, Rockville, Maryland - Picker International Inc, San Francisco, California), FY1991

    Science.gov (United States)

    1991-01-01

    AD-A249 050 0 1991 Prime Contract Awards Alphabetically by Contractor, State or Country, and Place. Part -13 (Rockville Maryland - San Francisco...88). DOE See authorities. Block 4. Title and Subtitle. A title is taken from NASA - See Handbook NHB 2200.2. the part of the report that provides the...aa 4-4-4 0-4 4--I -I >1-4 N -4 0-I -L-4 ( atomo <s.1 0 I mmm I Inin In We in .Id) .,40 N, E r-ar- U) -CO m ~ o mo Nf a. 1000 41 4( mmm "I <N N 4 Mt4 -a

  13. DETERMINACIÓN DE LAS FUNCIONES Y SERVICIOS PRESTADOS POR LOS COMPONENTES DE LA SAN DEL CECAD DE LA UNIVERSIDAD DISTRITAL FRANCISCO JOSÉ DE CALDAS

    Directory of Open Access Journals (Sweden)

    Roberto Ferro

    2012-05-01

    Full Text Available En este artículo se asignan las funciones y servicios que deben prestar los componentes de la Red de Almacenamiento  del Centro de Cómputo de Alto desempeño de la Universidad  Distrital Francisco José de Caldas. Para alcanzar este objetivo se realizaron varias pruebas entre los diferentes elementos  que conforman la SAN y se midieron las velocidades de  transferencia con la ayuda de herramientas especializadas.

  14. A Landscape-level Model for Ecosystem Restoration in the San Francisco Estuary and Its Watershed

    Directory of Open Access Journals (Sweden)

    Wim Kimmerer

    2005-03-01

    Full Text Available The CALFED Bay-Delta Program is an ambitious effort to restore ecosystems and improve reliability of ecosystem services in California’s Central Valley. Key issues for CALFED and its Ecosystem Restoration Program (ERP include (1 meeting societal demand for multiple, potentially conflicting ecosystem services; (2 the tradeoff among more or less environmentally intrusive approaches to solving problems; (3 whether restoration should focus at the ecosystem level or on individual species; (4 the appropriate response to uncertainty; and (5 the tension between action and investigation. A long-term, landscape-scale perspective is essential for framing the scientific questions underlying these broad issues. We introduce a landscape-scale conceptual model that illustrates linkages, including material flows and animal migration, among the major ecosystem components being described in detail in a series of review papers. This model shows how linkages between ecosystem components result in remote consequences of locally applied restoration actions. The network of linkages is made more complicated by human interventions, which add components not previously a part of the landscape (e.g., salmonid hatcheries and alter or even reverse causal relations. A landscape perspective also helps identify conceptual gaps in CALFED’s restoration strategy, such as climate change and human population growth, which should be explicitly considered in forecasts of the long-term prospects for restoration. A landscape perspective is no panacea; in particular, the effects of restoration at this scale will be difficult to detect. Nevertheless, we advocate integrating investigations of processes at nested, smaller scales as an approach for evaluating effects of individual restoration actions and of the entire program. We believe CALFED and other large restoration programs will be most successful if they are able to integrate both societal expectations and scientific study at the

  15. A Sr-Nd isotopic study of sand-sized sediment provenance and transport for the San Francisco Bay coastal system

    Science.gov (United States)

    Rosenbauer, Robert J.; Foxgrover, Amy C.; Hein, James R.; Swarzenski, Peter W.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    A diverse suite of geochemical tracers, including 87Sr/86Sr and 143Nd/144Nd isotope ratios, the rare earth elements (REEs), and select trace elements were used to determine sand-sized sediment provenance and transport pathways within the San Francisco Bay coastal system. This study complements a large interdisciplinary effort (Barnard et al., 2012) that seeks to better understand recent geomorphic change in a highly urbanized and dynamic estuarine-coastal setting. Sand-sized sediment provenance in this geologically complex system is important to estuarine resource managers and was assessed by examining the geographic distribution of this suite of geochemical tracers from the primary sources (fluvial and rock) throughout the bay, adjacent coast, and beaches. Due to their intrinsic geochemical nature, 143Nd/144Nd isotopic ratios provide the most resolved picture of where sediment in this system is likely sourced and how it moves through this estuarine system into the Pacific Ocean. For example, Nd isotopes confirm that the predominant source of sand-sized sediment to Suisun Bay, San Pablo Bay, and Central Bay is the Sierra Nevada Batholith via the Sacramento River, with lesser contributions from the Napa and San Joaquin Rivers. Isotopic ratios also reveal hot-spots of local sediment accumulation, such as the basalt and chert deposits around the Golden Gate Bridge and the high magnetite deposits of Ocean Beach. Sand-sized sediment that exits San Francisco Bay accumulates on the ebb-tidal delta and is in part conveyed southward by long-shore currents. Broadly, the geochemical tracers reveal a complex story of multiple sediment sources, dynamic intra-bay sediment mixing and reworking, and eventual dilution and transport by energetic marine processes. Combined geochemical results provide information on sediment movement into and through San Francisco Bay and further our understanding of how sustained anthropogenic activities which limit sediment inputs to the system (e

  16. Performance of rapid point-of-care and laboratory tests for acute and established HIV infection in San Francisco.

    Directory of Open Access Journals (Sweden)

    Christopher D Pilcher

    Full Text Available Current laboratory and point-of-care tests for HIV detect different analytes and use different sample types. Some have fast turnaround times (<1 hour. We investigated how HIV test choice could impact case finding by testing programs.We analyzed 21,234 consecutive HIV tests with venous blood obtained by San Francisco HIV testing programs from 2003 to 2008. For a subset, oral fluid (n = 6446 or fingerstick blood (n = 8127 samples were also obtained for rapid testing. In all cases, HIV status was determined using an HIV antibody-plus-RNA test algorithm. We assessed how the screening antibody tests performed individually versus the gold standard of the full algorithm. We then evaluated the potential ability of other tests (including new tests to detect more cases, by re-testing all specimens that had negative/discrepant antibody results on initial screening.The antibody-RNA algorithm identified 58 acute and 703 established HIV infection cases. 1(st-generation (Vironostika and 3(rd-generation (Genetic Systems immunoassays had 92 and 96 percent sensitivity, respectively. The Oraquick rapid test had clinical sensitivity of only 86 percent on oral fluid samples, but 92 percent on finger-stick blood. Newer 4(th-generation, antigen-antibody combo rapid immunoassay (ARCHITECT detected HIV in 87 percent of all the acute cases that had been missed by one of the previous screening assays. A point-of-care 4(th generation antigen-antibody combo rapid test (Determine detected about 54 percent of such acute cases.Our study suggests that some rapid antibody blood tests will give similar case detection to laboratory antibody tests, but that oral fluid testing greatly reduces ability to detect HIV. New 4(th-generation combo tests can detect the majority of acute infections detectable by HIV RNA but with rapid results. Using these tests as a primary screening assay in high-risk HIV testing programs could reduce or eliminate the need for HIV RNA testing.

  17. Novel analyses of long-term data provide a scientific basis for chlorophyll-a thresholds in San Francisco Bay

    Science.gov (United States)

    Sutula, Martha; Kudela, Raphael; Hagy, James D.; Harding, Lawrence W.; Senn, David; Cloern, James E.; Bricker, Suzanne B.; Beck, Marcus W.; Berg, Gry Mine

    2017-01-01

    San Francisco Bay (SFB), USA, is highly enriched in nitrogen and phosphorus, but has been resistant to the classic symptoms of eutrophication associated with over-production of phytoplankton. Observations in recent years suggest that this resistance may be weakening, shown by: significant increases of chlorophyll-a (chl-a) and decreases of dissolved oxygen (DO), common occurrences of phytoplankton taxa that can form Harmful Algal Blooms (HAB), and algal toxins in water and mussels reaching levels of concern. As a result, managers now ask: what levels of chl-a in SFB constitute tipping points of phytoplankton biomass beyond which water quality will become degraded, requiring significant nutrient reductions to avoid impairments? We analyzed data for DO, phytoplankton species composition, chl-a, and algal toxins to derive quantitative relationships between three indicators (HAB abundance, toxin concentrations, DO) and chl-a. Quantile regressions relating HAB abundance and DO to chl-a were significant, indicating SFB is at increased risk of adverse HAB and low DO levels if chl-a continues to increase. Conditional probability analysis (CPA) showed chl-a of 13 mg m−3 as a “protective” threshold below which probabilities for exceeding alert levels for HAB abundance and toxins were reduced. This threshold was similar to chl-a of 13–16 mg m−3 that would meet a SFB-wide 80% saturation Water Quality Criterion (WQC) for DO. Higher “at risk” chl-a thresholds from 25 to 40 mg m−3 corresponded to 0.5 probability of exceeding alert levels for HAB abundance, and for DO below a WQC of 5.0 mg L−1 designated for lower South Bay (LSB) and South Bay (SB). We submit these thresholds as a basis to assess eutrophication status of SFB and to inform nutrient management actions. This approach is transferrable to other estuaries to derive chl-a thresholds protective against eutrophication.

  18. The role of habitat-selection in restricting invasive blue mussel advancement to protect native populations in San Francisco Bay

    Science.gov (United States)

    Mittal, N.; Saarman, N. P.; Pogson, G.

    2013-12-01

    Introduced species contribute to decline of biodiversity and ecosystem services. Introduced species threaten native species by increasing competition for space and resources, changing their habitat, and disrupting species interactions. Protecting native species is crucial to preserving ecosystem services (i.e. medicinal, agricultural, ecological, and cultural benefits) for future generations. In marine communities, the number of invasive species is dramatically increasing every year, further magnifying the negative impact on native species. This research determines if habitat-specific selection can protect native species from their invasive relatives, and could allow targeted habitat restoration for native species to maintain high levels of biodiversity. Blue mussels provide an ideal system for studying the impact of an invasive species (Mytilus galloprovincialis) on native mussels (M. trossulus), because M. galloprovincialis is marked as one of the world's 100 worst invasive species. Hybridization between M. galloprovincialis and M. trossulus occurs wherever their distributions overlap (i.e. Japan, Puget Sound, and central California). In central California, hybrids form in a broad variety of habitats ever since M. galloprovincialis was introduced about 100 years ago. The current level of threat posed to native mussels in central California is unknown. When population growth rate of an invasive species is higher than the native within a hybrid zone, the invader's genes become more prominent in the hybrids than the native species' genes. This uneven mix of genes and decrease of pure native mussels threatens to drive M. trossulus to extinction. Therefore, it is important to research which environment fosters highest success of pure native species. We conducted a field experiment in San Francisco Bay where mussels were reared in different habitats. We then collected samples and extracted DNA from each treatment, and genotyped them by a next-generation sequencing

  19. Hydrogeochemistry of the formation waters in the San Francisco field, UMV basin, Colombia - A multivariate statistical approach

    Science.gov (United States)

    Cortes, J. E.; Muñoz, L. F.; Gonzalez, C. A.; Niño, J. E.; Polo, A.; Suspes, A.; Siachoque, S. C.; Hernández, A.; Trujillo, H.

    2016-08-01

    A wide variety of hydrogeochemical data were obtained through the analysis of the formation water samples collected from 118 producing wells from the San Francisco Oilfield (SFO) in the Upper Magdalena Valley (UMV) basin, Huila, Colombia. The study area is composed of deposited sandstone in fluvial-lacustrine marine environment, which characterized the formation waters as chloride-sodium water type. The brackish-saline facies identified can be attributed to evaporation, halite and dolomite dissolution along with water recharge of meteoric waters somewhere in the basin, probably from Magdalena River, the contribution of the SFO injection water system and significantly by the rock-water interaction. Some ionic ratios were used to confirm clearly that water-rock interactions play a significant role in the evolution of the hydrogeochemistry process in the SFO. The charge balance error ranges between -5.88% and 2.62% indicating very well balanced and mature water for blocks 1, 2 and 3 (north part of the field), and partially equilibrated and immature waters for blocks 4, 5, 6, 7, and 8 as is confirmed by Piper, Giggenbach, and Schöeller diagrams. Calculated scale and stability indices (Langelier, Ryznar, and Puckorius), besides halite and dolomite indexes, indicate that these formation waters are slightly saturated with respect to the calcite and dolomite and have strong tendency to the scale formation as well. Concentration maps were used to identify the geological factors that could have influenced its chemical composition and the hydrogeochemical processes involved in the field, such as halite dissolution, calcite or dolomite precipitation and cationic exchange reactions. The mineralogical distribution leads to the conclusion that the halite dissolution is mostly distributed in the Northeastern area of the SFO between B1, B3, B4, B5, and B6 blocks, the dolomite and calcite have greater concentrations between B5 and B6 blocks. The dissolved minerals followed the

  20. Vehicle speed prediction via a sliding-window time series analysis and an evolutionary least learning machine: A case study on San Francisco urban roads

    Directory of Open Access Journals (Sweden)

    Ladan Mozaffari

    2015-06-01

    Full Text Available The main goal of the current study is to take advantage of advanced numerical and intelligent tools to predict the speed of a vehicle using time series. It is clear that the uncertainty caused by temporal behavior of the driver as well as various external disturbances on the road will affect the vehicle speed, and thus, the vehicle power demands. The prediction of upcoming power demands can be employed by the vehicle powertrain control systems to improve significantly the fuel economy and emission performance. Therefore, it is important to systems design engineers and automotive industrialists to develop efficient numerical tools to overcome the risk of unpredictability associated with the vehicle speed profile on roads. In this study, the authors propose an intelligent tool called evolutionary least learning machine (E-LLM to forecast the vehicle speed sequence. To have a practical evaluation regarding the efficacy of E-LLM, the authors use the driving data collected on the San Francisco urban roads by a private Honda Insight vehicle. The concept of sliding window time series (SWTS analysis is used to prepare the database for the speed forecasting process. To evaluate the performance of the proposed technique, a number of well-known approaches, such as auto regressive (AR method, back-propagation neural network (BPNN, evolutionary extreme learning machine (E-ELM, extreme learning machine (ELM, and radial basis function neural network (RBFNN, are considered. The performances of the rival methods are then compared in terms of the mean square error (MSE, root mean square error (RMSE, mean absolute percentage error (MAPE, median absolute percentage error (MDAPE, and absolute fraction of variances (R2 metrics. Through an exhaustive comparative study, the authors observed that E-LLM is a powerful tool for predicting the vehicle speed profiles. The outcomes of the current study can be of use for the engineers of automotive industry who have been

  1. Sex, Status, and Sand: California Academy of Sciences' Teen Interns Examine Trends of the Pacific Mole Crab (Emerita analoga) at Ocean Beach, San Francisco

    Science.gov (United States)

    Chu, J. B.; Conrad-Saydah, A.; Cohen, S.; Tom, R.; Robins-Moloney, M.; Masters, D.; Mason, K.; Alfaro, F.

    2003-12-01

    Student interns from the California Academy of Sciences' Careers in Sciences program monitored the Pacific mole crab (Emerita analoga), or sand crabs, in collaboration with the Farallones Marine Sanctuary Association. These small crustaceans live in the swash zone of the sandy beach habitat. Sand crabs are important in the food web, and therefore their status can help indicate the health of the larger environment. The interns helped the Gulf of the Farallones National Marine Sanctuary by monitoring the abundance and distribution of sand crabs at Ocean Beach in San Francisco, California. Students set up transects perpendicular to the shoreline, collected 10 samples along the transect, measured the carapace length, determined the sex of each crab, and checked for the presence of eggs. Students monitored June through September, 2003. Trends examined included differences in the gender ratio, size frequency, and distribution along the beach. Students also compared their data to other student data taken from other sites in San Francisco and Marin counties during 2001-2003 from the online database at http://www.sandcrabs.org. Using comparisons, interns were able to better understand the processes and significance of studying marine species. Implementation of the project was invaluable in aiding the interns in their understanding of the natural sciences and the role of monitoring habitats in environmental health.

  2. Geohydrology, water quality, and water budgets of Golden Gate Park and the Lake Merced area in the western part of San Francisco, California

    Science.gov (United States)

    Yates, E.B.; Hamlin, S.N.; McCann, L.H.

    1990-01-01

    The groundwater resources in the western part of the San Francisco, groundwater budgets for Golden Gate Park and the Lake Merced area, and a surface-water budget for Lake Merced are described. A continuous groundwater basin underlies a 39-sq-mi coastal strip in the San Francisco Peninsula south of the city. Basin fill consists largely of sand and silt. An extensive subsurface clay layer is present near Lake Merced. Recharge is principally from rainfall and irrigation-return flow, with lesser amounts from leaking water and sewer pipes, which were identified in part by stable-isotope and major ion analyses. In Golden Gate Park, about 1, 070 acre-ft/yr of groundwater flows to the ocean. Water levels are not declining, and pumpage could be safely increased. However, nitrate concentrations in excess of Federal drinking-water standards in water from many wells may limit potential uses of groundwater. Groundwater in the Lake Merced area is in a state of overdraft, as indicated by long- term declines in the level of Lake Merced and by groundwater levels persistently below sea level in deep wells. Seawater intrusion has not been detected, however. A surface-water budget for Lake Merced indicates that the largest inflow is from shallow groundwater and the largest outflow is loss by evaporation. (USGS)

  3. Chronic sublethal effects of San Francisco Bay sediments on nereis (neanthes) arenaceodentata; effect of food ration on sediment toxicity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Moore, D.W.; Dillon, T.M.

    1993-09-01

    This report is designed to address concerns regarding the effect of food ration on toxicity during chronic sublethal sediment bioassays. To this end, a contaminated San Francisco Bay sediment and a clean control sediment were evaluated in a chronic sublethal test under a series of different food rations, with the marine polychaete worm Nereis (Neanthes) arenaceodentata. Animals were exposed from early juvenile stage through the onset of gametogenesis. Treatments were 2.OX, 1.OX, 0.5X, and 0.25X where X is the recommended food ration for laboratory cultures. Test end points were survival, growth, and reproduction. The contaminated sediment was a composite of several cores taken to project depth (38 ft (11.6 m) below mean low water mark) from an area in Oakland Inner Harbor known to be contaminated with polycyclic aromatic hydrocarbons and metals. Comparisons were made with a clean control sediment. The control sediment is used in the laboratory cultures of N. arenaceodentata and was collected from Sequim, WA. Mean percent survival of Neanthes was high (>90 percent) in both the contaminated and control sediment across all food ration treatments. Individual wet weights were significantly reduced with decreasing food ration in both contaminated and control sediments. Significant differences in wet weight between sediment types were observed at the 1.OX, 0.5X, and 0.25X rations. Reproduction (fecundity and emergent juvenile (EJ) production) was also Chronic sublethal, Neanthes, Dredged material, San Francisco Bay, Food ration, Sediment.

  4. Sediment transport patterns in the San Francisco Bay Coastal System from cross-validation of bedform asymmetry and modeled residual flux

    Science.gov (United States)

    Barnard, Patrick L.; Erikson, Li H.; Elias, Edwin P.L.; Dartnell, Peter; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    The morphology of ~ 45,000 bedforms from 13 multibeam bathymetry surveys was used as a proxy for identifying net bedload sediment transport directions and pathways throughout the San Francisco Bay estuary and adjacent outer coast. The spatially-averaged shape asymmetry of the bedforms reveals distinct pathways of ebb and flood transport. Additionally, the region-wide, ebb-oriented asymmetry of 5% suggests net seaward-directed transport within the estuarine-coastal system, with significant seaward asymmetry at the mouth of San Francisco Bay (11%), through the northern reaches of the Bay (7–8%), and among the largest bedforms (21% for λ > 50 m). This general indication for the net transport of sand to the open coast strongly suggests that anthropogenic removal of sediment from the estuary, particularly along clearly defined seaward transport pathways, will limit the supply of sand to chronically eroding, open-coast beaches. The bedform asymmetry measurements significantly agree (up to ~ 76%) with modeled annual residual transport directions derived from a hydrodynamically-calibrated numerical model, and the orientation of adjacent, flow-sculpted seafloor features such as mega-flute structures, providing a comprehensive validation of the technique. The methods described in this paper to determine well-defined, cross-validated sediment transport pathways can be applied to estuarine-coastal systems globally where bedforms are present. The results can inform and improve regional sediment management practices to more efficiently utilize often limited sediment resources and mitigate current and future sediment supply-related impacts.

  5. Integration of bed characteristics, geochemical tracers, current measurements, and numerical modeling for assessing the provenance of beach sand in the San Francisco Bay Coastal System

    Science.gov (United States)

    Barnard, Patrick L.; Foxgrover, Amy C.; Elias, Edwin P.L.; Erikson, Li H.; Hein, James R.; McGann, Mary; Mizell, Kira; Rosenbauer, Robert J.; Swarzenski, Peter W.; Takesue, Renee K.; Wong, Florence L.; Woodrow, Donald L.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    Over 150 million m3 of sand-sized sediment has disappeared from the central region of the San Francisco Bay Coastal System during the last half century. This enormous loss may reflect numerous anthropogenic influences, such as watershed damming, bay-fill development, aggregate mining, and dredging. The reduction in Bay sediment also appears to be linked to a reduction in sediment supply and recent widespread erosion of adjacent beaches, wetlands, and submarine environments. A unique, multi-faceted provenance study was performed to definitively establish the primary sources, sinks, and transport pathways of beach-sized sand in the region, thereby identifying the activities and processes that directly limit supply to the outer coast. This integrative program is based on comprehensive surficial sediment sampling of the San Francisco Bay Coastal System, including the seabed, Bay floor, area beaches, adjacent rock units, and major drainages. Analyses of sample morphometrics and biological composition (e.g., Foraminifera) were then integrated with a suite of tracers including 87Sr/86Sr and 143Nd/144Nd isotopes, rare earth elements, semi-quantitative X-ray diffraction mineralogy, and heavy minerals, and with process-based numerical modeling, in situ current measurements, and bedform asymmetry to robustly determine the provenance of beach-sized sand in the region.

  6. Analysis of Salinity Intrusion in the San Francisco Bay-Delta Using a GA-Optimized Neural Net, and Application of the Model to Prediction in the Elkhorn Slough Habitat

    Science.gov (United States)

    Thompson, D. E.; Rajkumar, T.

    2002-12-01

    The San Francisco Bay Delta is a large hydrodynamic complex that incorporates the Sacramento and San Joaquin Estuaries, the Suisan Marsh, and the San Francisco Bay proper. Competition exists for the use of this extensive water system both from the fisheries industry, the agricultural industry, and from the marine and estuarine animal species within the Delta. As tidal fluctuations occur, more saline water pushes upstream allowing fish to migrate beyond the Suisan Marsh for breeding and habitat occupation. However, the agriculture industry does not want extensive salinity intrusion to impact water quality for human and plant consumption. The balance is regulated by pumping stations located along the estuaries and reservoirs whereby flushing of fresh water keeps the saline intrusion at bay. The pumping schedule is driven by data collected at various locations within the Bay Delta and by numerical models that predict the salinity intrusion as part of a larger model of the system. The Interagency Ecological Program (IEP) for the San Francisco Bay / Sacramento-San Joaquin Estuary collects, monitors, and archives the data, and the Department of Water Resources provides a numerical model simulation (DSM2) from which predictions are made that drive the pumping schedule. A problem with DSM2 is that the numerical simulation takes roughly 16 hours to complete a prediction. We have created a neural net, optimized with a genetic algorithm, that takes as input the archived data from multiple gauging stations and predicts stage, salinity, and flow at the Carquinez Straits (at the downstream end of the Suisan Marsh). This model seems to be robust in its predictions and operates much faster than the current numerical DSM2 model. Because the Bay-Delta is strongly tidally driven, we used both Principal Component Analysis and Fast Fourier Transforms to discover dominant features within the IEP data. We then filtered out the dominant tidal forcing to discover non-primary tidal effects

  7. Mentoring the next generation of HIV prevention researchers: a model mentoring program at the University of California San Francisco and Gladstone Institute of Immunology and Virology Center for AIDS research.

    Science.gov (United States)

    Kahn, James; Des Jarlais, Christine D; Dobkin, Loren; Barrs, Sarah French; Greenblatt, Ruth M

    2008-03-01

    Mentoring is critical to develop and nurture early career investigators, helping them to succeed in building networks of colleagues, and is especially important for investigators focused on HIV research. We piloted a multidiscipline mentoring program targeting postdoctoral scholars and early career faculty concentrating on HIV/AIDS research. The pilot mentoring program was conducted at the Center for AIDS Research (CFAR) at the University of California San Francisco and the Gladstone Institute of Virology and Immunology. Mentees were self-referred postdoctoral scholars and early career faculty. Mentors were drawn from the senior faculty. Early career mentees were matched with senior investigators for individual meetings, a monthly workshop on topics directed by the mentees, and single-day mentoring seminars. More than 30 mentees and 20 mentors have participated in the pilot project. Most mentees reported that the 1-on-1 mentoring was a satisfying experience. The most highly valued activities were those that facilitated networking among mentees, networking between mentors and mentees, and workshops that focused on grant applications and first academic appointments and promotions. A multidisciplinary mentoring program for postdoctoral scholars and early career faculty focused on HIV/AIDS research is valuable. Umbrella organizations, such as the CFAR, are well suited to create and provide highly valued mentoring experiences.

  8. Handbook of Techniques and Guides for the Study of the San Francisco Bay-Delta-Estuary Complex, Part 1. Monitoring Techniques for the Measurement of Physico-Chemical and Biological Parameters.

    Science.gov (United States)

    Alameda County School Dept., Hayward, CA.

    Project MER (Marine Ecology Research) is aimed at improving environmental education in the San Francisco Bay Area schools. As part of meeting this goal, it is hoped that students and teachers can see the results of their efforts being put to practical use. This guide is the first of a series produced to help the students and teachers gather data…

  9. A Global Talent Magnet: How a San Francisco/Bay Area Global Higher Education Hub Could Advance California's Comparative Advantage in Attracting International Talent and Further Build US Economic Competitiveness. Research & Occasional Paper Series: CSHE.9.11

    Science.gov (United States)

    Douglass, John; Edelstein, Richard; Hoareau, Cecile

    2011-01-01

    During the 2009-10 academic year international students generated more than $18.8 billion in net income into the US economy. California alone had nearly 100,000 international students with an economic impact of nearly $3.0 billion. In this paper, we outline a strategy for the San Francisco/Bay Area to double the number of international students…

  10. Stable hydrogen and oxygen isotopes of tap water reveal structure of the San Francisco Bay Area's water system and adjustments during a major drought.

    Science.gov (United States)

    Tipple, Brett J; Jameel, Yusuf; Chau, Thuan H; Mancuso, Christy J; Bowen, Gabriel J; Dufour, Alexis; Chesson, Lesley A; Ehleringer, James R

    2017-08-01

    Water availability and sustainability in the Western United States is a major flashpoint among expanding communities, growing industries, and productive agricultural lands. This issue came to a head in 2015 in the State of California, when the State mandated a 25% reduction in urban water use following a multi-year drought that significantly depleted water resources. Water demands and challenges in supplying water are only expected to intensify as climate perturbations, such as the 2012-2015 California Drought, become more common. As a consequence, there is an increased need to understand linkages between urban centers, water transport and usage, and the impacts of climate change on water resources. To assess if stable hydrogen and oxygen isotope ratios could increase the understanding of these relationships within a megalopolis in the Western United States, we collected and analyzed 723 tap waters across the San Francisco Bay Area during seven collection campaigns spanning 21 months during 2013-2015. The San Francisco Bay Area was selected as it has well-characterized water management strategies and the 2012-2105 California Drought dramatically affected its water resources. Consistent with known water management strategies and previously collected isotope data, we found large spatiotemporal variations in the δ2H and δ18O values of tap waters within the Bay Area. This is indicative of complex water transport systems and varying municipality-scale management decisions. We observed δ2H and δ18O values of tap water consistent with waters originating from snowmelt from the Sierra Nevada Mountains, local precipitation, ground water, and partially evaporated reservoir sources. A cluster analysis of the isotope data collected in this study grouped waters from 43 static sampling sites that were associated with specific water utility providers within the San Francisco Bay Area and known management practices. Various management responses to the drought, such as source

  11. Affective foodscapes in an economy of passion : repetition, opposition and adaptation in Mexican restaurants in Amsterdam, Madrid and San Francisco

    NARCIS (Netherlands)

    Matus Ruiz, M.

    2012-01-01

    The
 main
 goal
 of
 my
 research
 was
 to
 analyze
 how
 the
 desire
 to
 affect
 and
 be
 affected
 by
 foreign
 signs
relates
 to
 the
 commoditization
 of
 food
 products
 offered
 in
 Mexican
 restaurants
 in
 Amsterdam,
 Madrid
and
 San
 Francisco.
 I
 conceive
 restaurants
 as
 foodscapes.


  12. Interview with René Yáñez, artist, co-founder of the Galería de la Raza, San Francisco, CA, USA, August 13, 2001 Entretien avec René Yáñez, artiste, co-fondateur de la Galería de la Raza, San Francisco, CA, Etats-Unis

    Directory of Open Access Journals (Sweden)

    Gérard Selbach

    2009-10-01

    Full Text Available René Yáñez is an all-round visual artist and visionary, now in his sixties. He came out of the Chicano movement of the 70’s and was instrumental in founding the Galería de la Raza in the Mission district of San Francisco. He remained some fifteen years as its director, curating exhibitions, directing and promoting emerging artists of all kinds. He then worked as director of cultural programming at the Mexican Museum until its closure. René Yáñez co-produced Mexican performance artist Astrid H...

  13. Interview with Jennie E. Rodríguez, Executive Director of the Mission Cultural Center for Latino Arts, San Francisco, CA, USA, August 15, 2001 Entretien avec Jennie E. Rodríguez, directrice, Mission Cultural Center for Latino Arts, San Francisco, CA, États-Unis

    Directory of Open Access Journals (Sweden)

    Gérard Selbach

    2009-10-01

    Full Text Available ForewordThe Mission Cultural Center for Latino Arts (MCCLA is located at 2868 Mission Street in San Francisco, in a district mainly inhabited by Hispanics and well-known for its numerous murals. The Center was founded in 1977 by artists and community activists who shared “the vision to promote, preserve and develop the Latino cultural arts that reflect the living tradition and experiences of Chicano, Central and South American, and Caribbean people.”August 2001 was as busy at the Center as a...

  14. Groundwater-quality data in the North San Francisco Bay Shallow Aquifer study unit, 2012: results from the California GAMA Program

    Science.gov (United States)

    Bennett, George L.; Fram, Miranda S.

    2014-01-01

    Groundwater quality in the 1,850-square-mile North San Francisco Bay Shallow Aquifer (NSF-SA) study unit was investigated by the U.S. Geological Survey (USGS) from April to August 2012, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001 and is being conducted in collaboration with the SWRCB and Lawrence Livermore National Laboratory (LLNL). The NSF-SA study unit was the first study unit to be sampled as part of the second phase of the GAMA-PBP, which focuses on the shallow aquifer system.

  15. Unevenness in Health at the Intersection of Gender and Sexuality: Sexual Minority Disparities in Alcohol and Drug Use Among Transwomen in the San Francisco Bay Area.

    Science.gov (United States)

    Arayasirikul, Sean; Pomart, W Andres; Raymond, H Fisher; Wilson, Erin C

    2018-01-01

    Research on the health of transwomen is largely focused on heterosexual HIV risk. Little is known about the health of sexual minority transwomen. We conducted a secondary cross-sectional analysis of data from a HIV risk and resilience study of transwomen aged 16 to 24 years in the San Francisco Bay Area (N = 259). Prevalence and demographic characteristics of sexual minority transwomen was assessed and logistic regression models were used to examine the relationship between sexual minority status and alcohol and drug use. In logistic regression models, sexual minority transwomen had greater fold odds of heavy episodic drinking and illicit prescription drug use compared to their heterosexual counterparts, controlling for race/ethnicity, age, income, nativity, hormone status, and history of feminization procedures. These results suggest that sexual minority status may be an important social determinant of health among gender minorities. Populations of transwomen are heterogeneous; effective interventions must consider sexual minority status.

  16. Actuación religiosa de civiles españoles en la orden tercera de San Francisco en Buenos Aires: 1725-1823

    Directory of Open Access Journals (Sweden)

    Siegrist de Gentile, Nora L.

    2001-12-01

    Full Text Available The present article takes part in two historical times: the modem one and the contemporaneous one due to the long-lasting of the evolution of one civil and religious order in Buenos Aires: Franciscan Third Order. This Order had a remarkable significance because of the spiritual and social evolution of her members.

    La presente comunicación se inserta en dos tiempos históricos: el moderno y el contemporáneo debido a la larga duración de la trayectoria de una orden civil-religiosa en Buenos Aires: la Orden Tercera de San Francisco. Ésta tuvo una notable trascendencia por el recorrido espiritual y social efectuado por los miembros que la compusieron.

  17. Transcribed sequences in the human genome to be held in San Francisco, November 7 and 8, 1992. Final report, September 1, 1992--August 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Gardiner, K.

    1993-11-01

    The Second International Workshop on the Identification of Transcribed Sequences was held in San Francisco on November 7--8, 1992. The purpose of the workshop was to discuss and evaluate techniques for developing a complete transcriptional map of the human genome. Such a map requires the positions, sequences, and expression patterns of all genes. This goal is being approached from two different directions, each with strengths and weaknesses. One method is to identify the transcribed sequences from genomic DNA of a given region; the other is to systematically sequence and map cDNAs. The cDNA approach yields sequence information rapidly, but mapping each cDNA is a technical challenge. In the first approach, the map locations of genomic sequences are known at the outset, and the challenge is to identify exons. The efficient construction of a transcriptional map will require a diverse array of techniques.

  18. La Basílica de San Francisco de Asís después del terremoto del 26 de septiembre de 1997

    Directory of Open Access Journals (Sweden)

    Giorgio Croci

    1998-12-01

    Full Text Available La Basílica de San Francisco de Asís, gravemente dañada tras los primeros terremotos de otoño de 1997, amenazaba con un colapso completo a raíz del estado de difícil equilibrio en que había quedado. La intervención descrita en este artículo explica cómo se pudo consolidar el templo dañado en tiempo récord, poco antes de un seísmo fortísimo que habría provocado con seguridad el derrumbamiento de gran parte de su cubierta, con la grave pérdida que este hecho hubiera supuesto para el patrimonio arquitectónico y la historia del arte italiana.

  19. Reforma religiosa, sociedad y política en la Baja Edad Media: el ejemplo de San Francisco de Palencia en el siglo XV

    Directory of Open Access Journals (Sweden)

    Rojo Alique, Francisco Javier

    2007-12-01

    Full Text Available This article focuses upon the issue of the reform of the Franciscan friary at Palencia, Spain, in the 15th century. It can provide a good example of the relationship between religious reforms and society in Medieval and Early Modern times. It also shows the role that political powers played in those reforms.El presente artículo describe cómo se produjo la implantación de la observancia en el convento de San Francisco de Palencia en el siglo XV. Se trata de un caso en el que se aprecia con bastante claridad la dimensión social que tuvieron las reformas religiosas bajomedievales, así como el papel que desempeñaron en las mismas los poderes políticos.

  20. Results of bulk sediment analysis and bioassay testing on selected sediments from Oakland Inner Harbor and Alcatraz disposal site, San Francisco, California

    Energy Technology Data Exchange (ETDEWEB)

    Word, J Q; Ward, J A; Woodruff, D L

    1990-09-01

    The Battelle/Marine Sciences Laboratory (MSL) was contracted by the US Army Corps of Engineers, San Francisco District, to perform bulk sediment analysis and oyster larvae bioassays (elutriate) on sediments from Inner Oakland Harbor, California. Analysis of sediment characteristics by MSL indicated elevated priority pollutants, PAHs, pesticides, metals, organotins, and oil and grease concentrations, when compared to Alcatraz Island Dredged Material Disposal Site sediment concentrations. Larvae of the Pacific oyster, Crassostrea gigas, were exposed to seawater collected from the Alcatraz Island Site water, and a series of controls using water and sediments collected from Sequim Bay, Washington. Exposure of larvae to the Alcatraz seawater and the 50% and 100% elutriate concentrations from each Oakland sediment resulted in low survival and a high proportion of abnormal larvae compared to Sequim Bay control exposures. MSL identified that field sample collection, preservation, and storage protocols used by Port of Oakland contractors were inconsistent with standard accepted practices. 23 refs., 10 figs., 40 tabs.

  1. Neurovascular and Immuno-Imaging: From Mechanisms to Therapies. Proceedings of the Inaugural Symposium, San Francisco, CA, USA March 10, 2015

    Directory of Open Access Journals (Sweden)

    Katerina eAkassoglou

    2016-02-01

    Full Text Available Breakthrough advances in intravital imaging have launched a new era for the study of dynamic interactions at the neurovascular interface in health and disease. The first Neurovascular and Immuno-Imaging Symposium was held at the Gladstone Institutes, University of California, San Francisco in March, 2015. This highly interactive symposium brought together a group of leading researchers who discussed how recent studies have unraveled fundamental biological mechanisms in diverse scientific fields such as neuroscience, immunology, and vascular biology, both under physiological and pathological conditions. These Proceedings highlight how advances in imaging technologies and their applications revolutionized our understanding of the communication between brain, immune, and vascular systems and identified novel targets for therapeutic intervention in neurological diseases.

  2. Simplifying consent for HIV testing is associated with an increase in HIV testing and case detection in highest risk groups, San Francisco January 2003-June 2007.

    Directory of Open Access Journals (Sweden)

    Nicola M Zetola

    2008-07-01

    Full Text Available Populations at highest risk for HIV infection face multiple barriers to HIV testing. To facilitate HIV testing procedures, the San Francisco General Hospital Medical Center eliminated required written patient consent for HIV testing in its medical settings in May 2006. To describe the change in HIV testing rates in different hospital settings and populations after the change in HIV testing policy in the SFDH medical center, we performed an observational study using interrupted time series analysis.Data from all patients aged 18 years and older seen from January 2003 through June 2007 at the San Francisco Department of Public Health (SFDPH medical care system were included in the analysis. The monthly HIV testing rate per 1000 had patient-visits was calculated for the overall population and stratified by hospital setting, age, sex, race/ethnicity, homelessness status, insurance status and primary language.By June 2007, the average monthly rate of HIV tests per 1000 patient-visits increased 4.38 (CI, 2.17-6.60, p<0.001 over the number predicted if the policy change had not occurred (representing a 44% increase. The monthly average number of new positive HIV tests increased from 8.9 (CI, 6.3-11.5 to 14.9 (CI, 10.6-19.2, p<0.001, representing a 67% increase. Although increases in HIV testing were seen in all populations, populations at highest risk for HIV infection, particularly men, the homeless, and the uninsured experienced the highest increases in monthly HIV testing rates after the policy change.The elimination of the requirement for written consent in May 2006 was associated with a significant and sustained increase in HIV testing rates and HIV case detection in the SFDPH medical center. Populations facing the higher barriers to HIV testing had the highest increases in HIV testing rates and case detection in response to the policy change.

  3. Creating Infrastructure Resilience from Information Chaos: The City and County of San Francisco's Approach to Sea Level Rise Science and Adaptation Planning

    Science.gov (United States)

    Behar, D. H.; Pfeffer, W. T.; May, K.; Mote, P.; Cayan, D. R.

    2014-12-01

    During one 17 month period ending October 2013, three major reports on sea level rise from three highly respected science providers produced three differing, in some cases wildly divergent, estimates of sea level rise through the year 2100. These reports, by the National Research Council, the IPCC, and the National Climate Assessment, collectively flummoxed the lay reader seeking direction on sea level rise projections to incorporate into adaptation planning. Guidance documents soon emerged from state entities, including regulatory agencies, which caused further confusion. The City and County of San Francisco, surrounded by water on three sides, began developing City-wide sea level rise guidance in 2013. A Sea Level Rise Committee featuring representatives of key infrastructure managers met over a nine month period, and their work included an in-depth review of the science of sea level rise. To convert divergent scientific reports into "actionable science" required not only a close reading of each but extensive expert elicitation to tease out the meaning behind each of the numbers and the associated uncertainties. In the end, sufficient consistency between the differing projections, fortified by political exigencies, allowed a "scientific consensus" with actionable science value for the City to surface. The resulting document, "Guidance for Incorporating Sea Level Rise into Capital Planning in San Francisco," begins by providing a scientific underpinning for planning, guidelines for incorporating uncertainty - particularly for accommodating multiple projections for any particular time slice - and outlines a four step process for assessment and adaptation. It also relies on new state-of-the-art inundation maps produced as part of the SFPUC's capital improvement program. Together, the Guidance and associated tools provide a road map for successful assessment and adaptation to sea level rise. We will also draw lessons from the experience that may be of value to

  4. The City and County of San Francisco's Approach to Sea Level Rise Science and Adaptation Planning: Creating Infrastructure Resilience from Information Chaos

    Science.gov (United States)

    Behar, D. H.; Pfeffer, W. T.; May, K.; Mote, P.; Cayan, D. R.

    2014-12-01

    During one 17 month period ending October 2013, three major reports on sea level rise from three highly respected science providers produced three differing, in some cases wildly divergent, estimates of sea level rise through the year 2100. These reports, by the National Research Council, the IPCC, and the National Climate Assessment, collectively flummoxed the lay reader seeking direction on sea level rise projections to incorporate into adaptation planning. Guidance documents soon emerged from state entities, including regulatory agencies, which caused further confusion. The City and County of San Francisco, surrounded by water on three sides, began developing City-wide sea level rise guidance in 2013. A Sea Level Rise Committee featuring representatives of key infrastructure managers met over a nine month period, and their work included an in-depth review of the science of sea level rise. To convert divergent scientific reports into "actionable science" required not only a close reading of each but extensive expert elicitation to tease out the meaning behind each of the numbers and the associated uncertainties. In the end, sufficient consistency between the differing projections, fortified by political exigencies, allowed a "scientific consensus" with actionable science value for the City to surface. The resulting document, "Guidance for Incorporating Sea Level Rise into Capital Planning in San Francisco," begins by providing a scientific underpinning for planning, guidelines for incorporating uncertainty - particularly for accommodating multiple projections for any particular time slice - and outlines a four step process for assessment and adaptation. It also relies on new state-of-the-art inundation maps produced as part of the SFPUC's capital improvement program. Together, the Guidance and associated tools provide a road map for successful assessment and adaptation to sea level rise. We will also draw lessons from the experience that may be of value to

  5. Application of an unstructured 3D finite volume numerical model to flows and salinity dynamics in the San Francisco Bay-Delta

    Science.gov (United States)

    Martyr-Koller, R. C.; Kernkamp, H. W. J.; van Dam, A.; van der Wegen, M.; Lucas, L. V.; Knowles, N.; Jaffe, B.; Fregoso, T. A.

    2017-06-01

    A linked modeling approach has been undertaken to understand the impacts of climate and infrastructure on aquatic ecology and water quality in the San Francisco Bay-Delta region. The Delft3D Flexible Mesh modeling suite is used in this effort for its 3D hydrodynamics, salinity, temperature and sediment dynamics, phytoplankton and water-quality coupling infrastructure, and linkage to a habitat suitability model. The hydrodynamic model component of the suite is D-Flow FM, a new 3D unstructured finite-volume model based on the Delft3D model. In this paper, D-Flow FM is applied to the San Francisco Bay-Delta to investigate tidal, seasonal and annual dynamics of water levels, river flows and salinity under historical environmental and infrastructural conditions. The model is driven by historical winds, tides, ocean salinity, and river flows, and includes federal, state, and local freshwater withdrawals, and regional gate and barrier operations. The model is calibrated over a 9-month period, and subsequently validated for water levels, flows, and 3D salinity dynamics over a 2 year period. Model performance was quantified using several model assessment metrics and visualized through target diagrams. These metrics indicate that the model accurately estimated water levels, flows, and salinity over wide-ranging tidal and fluvial conditions, and the model can be used to investigate detailed circulation and salinity patterns throughout the Bay-Delta. The hydrodynamics produced through this effort will be used to drive affiliated sediment, phytoplankton, and contaminant hindcast efforts and habitat suitability assessments for fish and bivalves. The modeling framework applied here will serve as a baseline to ultimately shed light on potential ecosystem change over the current century.

  6. Application of an unstructured 3D finite volume numerical model to flows and salinity dynamics in the San Francisco Bay-Delta

    Science.gov (United States)

    Martyr-Koller, R.C.; Kernkamp, H.W.J.; Van Dam, Anne A.; Mick van der Wegen,; Lucas, Lisa; Knowles, N.; Jaffe, B.; Fregoso, T.A.

    2017-01-01

    A linked modeling approach has been undertaken to understand the impacts of climate and infrastructure on aquatic ecology and water quality in the San Francisco Bay-Delta region. The Delft3D Flexible Mesh modeling suite is used in this effort for its 3D hydrodynamics, salinity, temperature and sediment dynamics, phytoplankton and water-quality coupling infrastructure, and linkage to a habitat suitability model. The hydrodynamic model component of the suite is D-Flow FM, a new 3D unstructured finite-volume model based on the Delft3D model. In this paper, D-Flow FM is applied to the San Francisco Bay-Delta to investigate tidal, seasonal and annual dynamics of water levels, river flows and salinity under historical environmental and infrastructural conditions. The model is driven by historical winds, tides, ocean salinity, and river flows, and includes federal, state, and local freshwater withdrawals, and regional gate and barrier operations. The model is calibrated over a 9-month period, and subsequently validated for water levels, flows, and 3D salinity dynamics over a 2 year period.Model performance was quantified using several model assessment metrics and visualized through target diagrams. These metrics indicate that the model accurately estimated water levels, flows, and salinity over wide-ranging tidal and fluvial conditions, and the model can be used to investigate detailed circulation and salinity patterns throughout the Bay-Delta. The hydrodynamics produced through this effort will be used to drive affiliated sediment, phytoplankton, and contaminant hindcast efforts and habitat suitability assessments for fish and bivalves. The modeling framework applied here will serve as a baseline to ultimately shed light on potential ecosystem change over the current century.

  7. Gay and bisexual men engage in fewer risky sexual behaviors while traveling internationally: a cross-sectional study in San Francisco.

    Science.gov (United States)

    Truong, Hong-Ha M; Fatch, Robin; Grasso, Michael; Robertson, Tyler; Tao, Luke; Chen, Yea-Hung; Curotto, Alberto; McFarland, Willi; Grant, Robert M; Reznick, Olga; Raymond, H Fisher; Steward, Wayne T

    2015-05-01

    International travel poses potential challenges to HIV prevention. A number of studies have observed an association between travel and behavioural disinhibition. In the present study, we assessed differences in sexual behaviour while travelling internationally and within the USA, compared with being in the home environment. A probability-based sample of men who have sex with men (MSM) from the San Francisco Bay Area who had travelled internationally in the previous 12 months was recruited through an adapted respondent-driven sampling methodology (N=501). Participants completed interviewer-administered, computer-assisted surveys. Detailed partner-by-partner behavioural data by destination type were collected on 2925 sexual partnerships: 1028 while travelling internationally, 665 while travelling within the USA and 1232 while staying in the San Francisco Bay Area. The proportion of partnerships during international travel that involved unprotected anal intercourse (UAI) was lower compared with during domestic travel and staying locally. International travel was associated with decreased odds of receptive UAI (AOR=0.65, p=0.02) compared with staying locally and there was a trend towards decreased odds of insertive UAI (AOR=0.70, p=0.07). MSM engaged in proportionately fewer sexual activities which present a high HIV transmission risk when travelling internationally, namely unprotected receptive and insertive anal intercourse and particularly with HIV serodiscordant partners. The lower sexual risk-taking during international travel was robust to controlling for many factors, including self-reported HIV serostatus, age, relationship status and type of partnership. These findings suggest that when travelling internationally, MSM may experience behavioural disinhibition to a lesser extent than had been described previously. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  8. Is drinking water a risk factor for endemic cryptosporidiosis? A case-control study in the immunocompetent general population of the San Francisco Bay Area

    Directory of Open Access Journals (Sweden)

    Nadle Joelle

    2003-03-01

    Full Text Available Abstract Background Cryptosporidiosis, caused by Cryptosporidium, is an enteric illness that has received much attention as an infection of immunocompromised persons as well as in community outbreaks (frequently waterborne. There are, however, no studies of the risk factors for sporadic community-acquired cryptosporidiosis in the immunocompetent US population. We undertook a case-control study in the San Francisco Bay Area as part of a national study sponsored by the Centers for Disease Control and Prevention to ascertain the major routes of transmission for endemic cryptosporidiosis, with an emphasis on evaluating risk from drinking water. Methods Cases were recruited from a population-based, active surveillance system and age-matched controls were recruited using sequential random-digit dialing. Cases (n = 26 and controls (n = 62 were interviewed by telephone using a standardized questionnaire that included information about the following exposures: drinking water, recreational water, food items, travel, animal contact, and person-to-person fecal contact, and (for adults sexual practices. Results In multivariate conditional logistic regression analyses no significant association with drinking water was detected. The major risk factor for cryptosporidiosis in the San Francisco Bay Area was travel to another country (matched odds ratio [95% confidence interval]: 24.1 [2.6, 220]. Conclusion The results of this study do not support the hypothesis that drinking water is an independent risk factor for cryptosporidiosis among the immunocompetent population. These findings should be used to design larger studies of endemic cryptosporidiosis to elucidate the precise mechanisms of transmission, whether waterborne or other.

  9. Acculturation, Dietary Practices and Risk for Childhood Obesity in an Ethnically Heterogeneous Population of Latino School Children in the San Francisco Bay Area

    Science.gov (United States)

    Schwartz, Norah; Jiménez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Heyman, Melvin B.

    2015-01-01

    Previous studies have found increased acculturation to the US lifestyle increases risk for obesity in Latinos. However, methodologies differ, and results in children are inconsistent. Moreover, previous studies have not evaluated risk factors within the heterogeneous US population. We recruited 144 self-identified Latino school children and their mother or father in grades 4–6 in San Francisco parochial schools and South San Francisco public schools using an information letter distributed to all students. Children and parents had weights, heights, demographic information, dietary patterns and lifestyle variables collected in English or Spanish through an interview format. A high percentage of our children were overweight [≥85th percentile body mass index (BMI)] (62.5%) and obese (≥95th percentile BMI) (45.2%). Correspondingly parents also had a high percentage of overweight (BMI ≥ 25 & obesity (BMI ≥ 30) (45.3%). Mexico was the country of origin for 62.2% of parents, and 26.6% were from Central or South America. In multivariate logistic analysis, speaking Spanish at home was an independent risk factor for obesity [odds ratio (OR) 2.97, 95% confidence interval (CI) 1.28–6.86]. Eating breakfast daily (OR 0.34, 95% CI 0.15–0.78) and consumption of tortas (a Mexican fast food sandwich) (OR 0.45, 95% CI 0.21–1.00) were associated with decreased risk. In stratified analysis, significant differences in risk factors existed between Mexican origin versus Central/South American Latino children. The processes of acculturation likely impact eating and lifestyle practices differentially among Latino groups. Interventions should focus on ensuring that all children eat a nutritious breakfast and take into consideration ethnicity when working with Latino populations. PMID:22101726

  10. Acculturation, dietary practices and risk for childhood obesity in an ethnically heterogeneous population of Latino school children in the San Francisco bay area.

    Science.gov (United States)

    Wojcicki, Janet M; Schwartz, Norah; Jiménez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Heyman, Melvin B

    2012-08-01

    Previous studies have found increased acculturation to the US lifestyle increases risk for obesity in Latinos. However, methodologies differ, and results in children are inconsistent. Moreover, previous studies have not evaluated risk factors within the heterogeneous US population. We recruited 144 self-identified Latino school children and their mother or father in grades 4-6 in San Francisco parochial schools and South San Francisco public schools using an information letter distributed to all students. Children and parents had weights, heights, demographic information, dietary patterns and lifestyle variables collected in English or Spanish through an interview format. A high percentage of our children were overweight [≥85th percentile body mass index (BMI)] (62.5%) and obese (≥95th percentile BMI) (45.2%). Correspondingly parents also had a high percentage of overweight (BMI ≥ 25 & obesity (BMI ≥ 30) (45.3%). Mexico was the country of origin for 62.2% of parents, and 26.6% were from Central or South America. In multivariate logistic analysis, speaking Spanish at home was an independent risk factor for obesity [odds ratio (OR) 2.97, 95% confidence interval (CI) 1.28-6.86]. Eating breakfast daily (OR 0.34, 95% CI 0.15-0.78) and consumption of tortas (a Mexican fast food sandwich) (OR 0.45, 95% CI 0.21-1.00) were associated with decreased risk. In stratified analysis, significant differences in risk factors existed between Mexican origin versus Central/South American Latino children. The processes of acculturation likely impact eating and lifestyle practices differentially among Latino groups. Interventions should focus on ensuring that all children eat a nutritious breakfast and take into consideration ethnicity when working with Latino populations.

  11. Brief Report: Psychosocial Predictors of Engagement in Sexual Risk Behavior Among Trans*female Youth Aged 16-24 Years in San Francisco.

    Science.gov (United States)

    Turner, Caitlin M; Santos, Glenn-Milo; Arayasirikul, Sean; Wilson, Erin C

    2017-03-01

    Trans*female youth (TFY) carry a disproportionate burden of HIV. Few longitudinal studies have analyzed both proximal and upstream predictors of changes in HIV-related risk behaviors for TFY. The aim of the present analysis was to identify psychosocial predictors of changes in sexual risk behavior over time for TFY in the San Francisco Bay Area. Data come from the SHINE cohort study conducted at the San Francisco Department of Public Health from 2012 to 2014 (n = 263). The relationship between hypothesized psychosocial factors and changes in engagement in condomless receptive anal intercourse over 12-month follow-up was modeled using generalized estimating equations, after adjusting for participant age, race/ethnicity, and education level. TFY who were ever in a serious relationship since identifying as trans* [adjusted odds ratio (aOR) = 1.89, 95% confidence interval (CI): 1.16 to 3.08], those who reported recent crack/cocaine use (aOR = 2.01, 95% CI: 1.05 to 3.85), and those with a monthly income of more than $500 (aOR = 0.55, 95% CI: 0.35 to 0.85) had significantly higher odds of condomless receptive anal intercourse over the 12-month study period compared to TFY without these exposures. Those who reported high exposure to gender-based discrimination had increased adjusted odds of engagement in condomless receptive anal intercourse compared to those who had low exposure over the study period (aOR = 1.70, 95% CI: 1.10 to 2.63). Both proximal and structural factors predicted increased engagement in sexual risk behavior among TFY. Results demonstrate the need for a multilevel approach to HIV prevention strategies for this population.

  12. Race/ethnicity, education, and age are associated with engagement in ecological momentary assessment text messaging among substance-using MSM in San Francisco.

    Science.gov (United States)

    Turner, Caitlin M; Coffin, Phillip; Santos, Deirdre; Huffaker, Shannon; Matheson, Tim; Euren, Jason; DeMartini, Anna; Rowe, Chris; Batki, Steven; Santos, Glenn-Milo

    2017-04-01

    Ecological momentary assessments (EMA) are data collection approaches that characterize behaviors in real-time. However, EMA is underutilized in alcohol and substance use research among men who have sex with men (MSM). The aim of this analysis is to explore the correlates of engagement in EMA text messages among substance-using MSM in San Francisco. The present analysis uses data collected from the Project iN pilot study (n=30). Over a two-month period, participants received and responded to EMA daily text messages inquiring about their study medication, alcohol, and methamphetamine use. Baseline characteristics including demographics, alcohol use, and substance use were examined as potential correlates of engagement in EMA text messages in logistic regression and proportional hazards models. Participants had a 74% response rate to EMA text messages over the study period. MSM of color had significantly lower adjusted odds of responding to EMA texts 80% of the time or more, compared to white MSM (adjusted odds ratio=0.05, 95%CI=0.01-0.38). College-educated MSM had a lower adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=0.12, 95%CI=0.02-0.63). Older MSM had a higher adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=1.15, 95%CI=1.01-1.31). Differences in engagement in EMA text prompts were discovered for MSM with different racial/ethnic backgrounds, ages, and education levels. Substance use variables were not correlated with engagement in text messages, suggesting that EMA may be a useful research tool among actively substance-using MSM in San Francisco. Published by Elsevier Inc.

  13. Waves and tides responsible for the intermittent closure of the entrance of a small, sheltered tidal wetland at San Francisco, CA

    Science.gov (United States)

    Hanes, D.M.; Ward, K.; Erikson, L.H.

    2011-01-01

    Crissy Field Marsh (CFM; http://www.nps.gov/prsf/planyourvisit/crissy-field-marsh-and-beach.htm) is a small, restored tidal wetland located in the entrance to San Francisco Bay just east of the Golden Gate. The marsh is small but otherwise fairly typical of many such restored wetlands worldwide. The marsh is hydraulically connected to the bay and the adjacent Pacific Ocean by a narrow sandy channel. The channel often migrates and sometimes closes completely, which effectively blocks the tidal connection to the ocean and disrupts the hydraulics and ecology of the marsh. Field measurements of waves and tides have been examined in order to evaluate the conditions responsible for the intermittent closure of the marsh entrance. The most important factor found to bring about the entrance channel closure is the occurrence of large ocean waves. However, there were also a few closure events during times with relatively small offshore waves. Examination of the deep-water directional wave spectra during these times indicates the presence of a small secondary peak corresponding to long period swell from the southern hemisphere, indicating that CFM and San Francisco Bay in general may be more susceptible to long period ocean swell emanating from the south or southwest than the more common ocean waves coming from the northwest. The tidal records during closure events show no strong relationship between closures and tides, other than that closures tend to occur during multi-day periods with successively increasing high tides. It can be inferred from these findings that the most important process to the intermittent closure of the entrance to CFM is littoral sediment transport driven by the influence of ocean swell waves breaking along the CFM shoreline at oblique angles. During periods of large, oblique waves the littoral transport of sand likely overwhelms the scour potential of the tidal flow in the entrance channel. ?? 2011.

  14. The influence of salinity and restoration on wetland soil microbial communities and carbon cycling in the San Francisco Bay-Delta Region

    Science.gov (United States)

    Theroux, S.; Hartman, W.; He, S.; Windham-Myers, L.; Tringe, S. G.

    2014-12-01

    Climate change is predicted to increase the average salinity of the San Francisco Bay-Delta watershed as sea levels rise and alpine snow volume decreases. Wetland soil microbial communities are responsible for cycling greenhouse gases and their response to climate change will heavily influence whether increasing salinity will have a negative or positive effect on the net greenhouse gas budgets of wetlands. To better understand the underlying factors determining the balance of greenhouse gas flux in wetland soils, we targeted the microbial communities along a salinity gradient ranging from freshwater to full seawater in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we sampled sixteen sites capturing a range of wetland plant types and restoration states. We determined a suite of soil biogeochemical parameters including moisture, carbon and nutrient contents, pH, sulfate, chloride, and trace metal concentrations. The results of our microbial diversity survey (16S rRNA gene Illumina tag sequencing) showed that salinity and sampling location were the primary drivers of belowground microbial community composition. Freshwater wetland soils, with lower sulfate concentrations, produced more methane than saline sites and we found a parallel increase in the relative abundance of methanogen populations in the high-methane samples. Surprisingly, wetland restoration status did not significantly alter microbial community composition, despite orders of magnitude greater methane flux in restored wetlands compared to reference sites. Deeper metagenomic and metatranscriptomic sequencing in a restored wetland allowed us to further evaluate the roles of methanogen abundance and activity in shaping soil methane production. Our study links belowground microbial communities with their greenhouse gas production, providing a mechanistic microbial framework for assessing climate change feedbacks in wetland soils resulting from sea

  15. Diversidade genética de Enterolobium contortisiliquum (Vell. Morong. no Baixo Rio São Francisco, por meio de marcadores RAPD Genetic diversity of Enterolobium contortisiliquum (Vell. Morong. in the low San Francisco river by RAPD markers

    Directory of Open Access Journals (Sweden)

    Georgea da Cruz Santana

    2008-06-01

    Full Text Available Enterolobium contortisiliquum Vell. Morong (Leguminosae-Mimosoideae é uma espécie muito utilizada em programas de recuperação de matas ciliares no Baixo Rio São Francisco, devido ao seu rápido crescimento inicial. Assim, o objetivo deste trabalho foi avaliar, por meio de marcadores moleculares RAPD, a diversidade genética de oito indivíduos de uma população remanescente dessa espécie, visando contribuir para a definição de estratégias de coleta de sementes. Os indivíduos estão situados em uma área de 100 ha de mata ciliar do Baixo Rio São Francisco. Para a extração do DNA, pelo método CTAB 2%, foram utilizadas folhas tenras dos indivíduos. Testaram-se 20 oligonucleotídios de 10 bases de seqüência arbitrária, cujos produtos foram separados em gel de agarose 0,8%, submetidos à eletroforese horizontal, corados com brometo-de-etídio e visualizados em luz ultravioleta. A similaridade genética entre os indivíduos foi calculada pelo Coeficiente de Similaridade de Jaccard e a construção do dendrograma, realizada utilizando-se o método UPGMA. O valor médio de diversidade genética entre as matrizes foi de 49%, variando de 33 a 85%. Os indivíduos 6 e 7 apresentaram relativa proximidade genética (67%, não sendo indicado o plantio de suas mudas ou semeadura direta para recuperação de área ciliar em locais muito próximos. A partir dos resultados observados, podem-se desenvolver estratégias para a coleta de sementes e produção de mudas, auxiliando, assim, programas de restauração ambiental.Enterolobium contortisiliquum Vell. Morong (Leguminosae-Mimosoideae is very much used in riparian forest restoration programs in the Low San Francisco River because of its fast initial growth. The objective of this work was to evaluate by RAPD molecular markers the genetic diversity of eight individuals of a remaining population of this species, in order to contribute for the definition of strategies for seed production. The

  16. High resolution measurements of aseismic slip (creep) on the San Andreas fault system from Parkfield to San Francisco Bay area; 1966 to the present

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide measures of aseismic slip (creep) at approximately 40 sites located on the San Andreas, Hayward, and Calaveras faults in Central California from...

  17. Competição de genótipos de goiabeira (Psidium guajava L. na região do submédio São Francisco Evaluation of guava genotypes in the submiddle of San Francisco Valley

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Neto

    2003-12-01

    Full Text Available Com objetivo de avaliar e selecionar genótipos de goiabeira que possam incrementar o sistema de produção da cultura na região do Submédio São Francisco foi desenvolvido na Estação Experimental de Bebedouro, base física da Embrapa Semi-Árido, em Petrolina-PE, um experimento em blocos ao acaso com cinco tratamentos (Paluma, Red Fleshed, Surubim, Red Selection of Florida e Ruby Supreme e cinco repetições. Considerando os resultados obtidos relativos a primeira e segunda poda de frutificação e análise conjunta dos dois anos de produção, observou-se que a variedade Surubim apresentou tendência de maior produção e maior número de frutos, entre os genótipos estudados.The objective of this study was to discriminate and select guava genotypes to improve the crop production system in the Submiddle of San Francisco Valley. An experiment was carried out at the Bebedouro Experimental Sation that belongs to Embrapa Semiarid in Petrolina, State of Pernambuco, with five genotypes of guava: Paluma, Red Fleshed, Surubim, Red Selection of Florida and Ruby Supreme. A randomized block design was used as statistical model with five treataments, and five repetitions. The results, related to the first and the second fruit set prunings and two year of combined analyses for fruit yield, indicated that Surubim variety tended to higher yield and greater number of fruits among the five genotypes tested.

  18. Coupling alongshore variations in wave energy to beach morphologic change using the SWAN wave model at Ocean Beach, San Francisco, CA

    Science.gov (United States)

    Eshleman, Jodi L.; Barnard, Patrick L.; Erikson, Li H.; Hanes, Daniel M.

    2007-01-01

    Coastal managers have faced increasing pressure to manage their resources wisely over the last century as a result of heightened development and changing environmental forcing. It is crucial to understand seasonal changes in beach volume and shape in order to identify areas vulnerable to accelerated erosion. Shepard (1950) was among the first to quantify seasonal beach cycles. Sonu and Van Beek (1971) and Wright et al. (1985) described commonly occurring beach states. Most studies utilize widest spaced 2-D cross shore profiles or shorelines extracted from aerial photographs (e.g. Winant et al. 1975; Aubrey, 1979, Aubrey and Ross, 1985; Larson and Kraus, 1994; Jimenez et al., 1977; Lacey and Peck, 1998; Guillen et al., 1999; Norcorss et al., 2002) to analyzed systematic changes in beach evolution. But with the exception of established field stations, such as Duck, NC (Birkemeier and Mason, 1984), ans Hazaki Oceanographical Research Station (HORS) in Japan (Katoh, 1997), there are very few beach change data sets with high temporal and spatial resolutions (e.g. Dail et al., 2000; Ruggiero et al., 2005; Yates et al., in press). Comprehensive sets of nearshore morphological data and local in situ measurements outside of these field stations are very rare and virtually non-existent high-energy coasts. Studied that have attempted to relate wave statistics to beach morphology change require some knowledge of the nearshore wave climate, and have had limited success using offshore measurement (Sonu and Van Beek, 1971; Dail et al., 2000). The primary objective of this study is to qualitatively compare spatially variable nearshore wave predictions to beach change measurements in order to understand the processes responsible for a persistent erosion 'hotspot' at Ocean Beach, San Francisco, CA. Local wave measurements are used to calibrate and validate a wave model that provides nearshore wave prediction along the beach. The model is run for thousands of binned offshore wave

  19. Una Aparición de la Virgen con el Niño a san Felipe Neri de Francisco Ignacio Ruiz de la Iglesia: atribución y contexto iconográfico

    Directory of Open Access Journals (Sweden)

    Gutiérrez Pastor, Ismael

    2013-06-01

    Full Text Available The author studies a painting of the Apparition of the Virgin and Child with St. Philip Neri, attributing it to the painter Francisco Ignacio Ruiz de la Iglesia and analyzing its iconography in the context of Baroque painting in Madrid.Se estudia una pintura de la Aparición de la Virgen con el Niño a San Felipe Neri, se atribuye al pintor Francisco Ignacio Ruiz de la Iglesia y se analiza su iconografía en el contexto de la pintura madrileña del Barroco.

  20. Monitoring the Northern San Francisco Bay Water Quality with Landsat-8. Nicholas B. Tufillaroa , and Curtiss O. Davisa. aOregon State University, Corvallis, OR, 97331, USA, nbt@coas.oregonstate.edu

    Science.gov (United States)

    Davis, C. O.; Tufillaro, N.

    2016-02-01

    Landsat-8's high spatial resolution ( 30 nm nominal), improved signal-to-noise (12bit digitizer) and expanded band set open up new applications for coastal and in-land waters. We use a recent ocean color processor for Landsat-8 created by Vanhellemont and Ruddick (RSE, 2015)to examine changes in the Northern San Francisco Bay, in particular looking for possiblechanges due to the on-going California drought. For instance, a temporary drought barrier to prevent salt water intrusion was placed during May of 2015 at West False River in the Sacramento-San Joaquin Delta. Using the new Landsat-8 ocean color products, we illustrate how to monitor changes in macro algae and plants (Sago pondweed (native), Curly pondweed (non-native)) in regions directly effected,such as the Franks Track region. Product maps using panchromatic enhancement ( 15 m resolution) andscene based atmospheric correction allow a detailed synoptic look every 16 days during theSpring, Summer, and Fall of 2015. This work is part of a larger NASA funded project aimed atimproving the modeling and predictive capabilities of the biogeochemical state for the San Francisco Bay(Davis, PI: Impacts of Population Growth on the San Francisco Bay and Delta Ecosystem, 2014-2017).