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This paper examines long-term recovery outcomes of businesses impacted by major natural disasters. Data were collected via two large-scale mail surveys—one administered to Santa Cruz County, California businesses 8 years after the Loma Prieta earthquake and the other administered to businesses in South Dade County, Florida, 6 years after Hurricane Andrew. Based on the results of OLS regression models, we argue that long-term recovery experiences of businesses are affected by various factors, including the economic sector in which a business operates, its age and financial condition, and the scope of its primary market; direct and indirect disaster impacts, including physical damage, forced closure, and disruption of operations; and owner perceptions of the broader economic climate. Previous disaster experience, level of disaster preparedness, and use of external sources of aid were not found to significantly affect the long-term economic viability of businesses in the two study communities. [Copyright &y& Elsevier]

• The study investigated the transferability of real-time safety models for signalized intersections to new jurisdictions. • The real-time safety models relate rear-end conflicts at through lanes to various dynamic traffic parameters. • Two corridors in California and Atlanta States were used in the analysis as destination jurisdictions. • The models' transferability was evaluated with and without a local calibration at the new jurisdictions. • The results showed that the models are transferable and can be used for real-time safety optimization. Optimizing traffic signals in real-time for safety performance can be executable in the era of Connected Vehicles (CVs) when real-time information on vehicle positions and trajectories is available. To achieve this, real-time safety models are needed to understand how changes in signal controllers affect safety in real-time. Recently, several real-time safety models were developed for signalized intersections that relate various dynamic traffic parameters to the number of rear-end traffic conflicts at the signal cycle level. The traffic parameters included: traffic volume, maximum queue length, shock wave speed and area, and platoon ratio. For wider application of these models to other jurisdictions, the transferability of these models needs to be examined. Therefore, this paper aims to investigate the transferability of several signalized intersections real-time safety models to new jurisdictions. Two corridors of signalized intersections in California and Atlanta were used in the analysis as destination jurisdictions. Detailed vehicle trajectories for these corridors were obtained from the Next Generation Simulation (NGSIM) data. Various transferability analysis approaches were applied. The transferability of the real-time safety models was evaluated with and without a local calibration for the model parameters at the new jurisdictions. Several goodness-of-fit measures were examined to assess the ability of the developed models to predict traffic conflicts. Overall, the results showed that the real-time safety models are transferable, which confirms the validity of using them for real-time safety evaluation of signalized intersections. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Technology cost and utility rate structure are key drivers of economic viability of solar and storage systems. • Solar-plus-storage systems are more often economical under time of use and demand charge rates. • Savings from storage-only projects come mainly from demand charge reductions; solar combined with storage also provides energy charge savings. • Savings from solar with storage is largely independent of building load variability, likely due to the energy cost reductions from the solar. Abstract This paper explores the economics of solar-plus-storage projects for commercial-scale, behind-the-meter applications. It provides insight into the near-term and future solar-plus-storage market opportunities across the U.S. We explore the impacts of location, building load profile, technology cost, utility rate structure, and policies on solar-plus-storage economic viability, and identify which factors are most significant to project economics. While savings from storage-only projects are largely derived from demand charge reductions, solar combined with storage also provides significant energy charge savings. A common assumption is that load profiles with peaks are likely candidates for savings from storage, due to the opportunity for demand charge reduction. Our results indicate that potential for savings from combining solar with storage is independent of building load variability, likely due to the energy cost reductions from the solar. Systems are more often economical under time of use and demand charge rates, particularly when demand charges are >$10 per kilowatt. Where systems were found to be economical, expected lifetime savings averaged between 7%–10%, with savings of 30% in numerous cases. Near term markets exist for solar-plus-storage in locations such as California and New York. As technology prices drop, the number of building types that can benefit increase, and additional markets appear in Colorado, New Mexico, and Alaska. All data from the study and interactive modeling results are available at: https://openei.org/wiki/Solar+Storage. [ABSTRACT FROM AUTHOR]

Heroin overdose, more accurately termed ‘heroin-related overdose’ due to the frequent involvement of other drugs, is the leading cause of mortality among regular heroin users. (Degenhardt et al., 2010) Heroin injectors are at greater risk of hospital admission for heroin-related overdose (HOD) in the eastern United States where Colombian-sourced powder heroin is sold than in the western US where black ‘tar’ heroin predominates. (Unick et al., 2014) This paper examines under-researched influences on HOD, both fatal and non-fatal, using data from a qualitative study of injecting drug users of black tar heroin in San Francisco and powder heroin in Philadelphia Data were collected through in-depth, semi-structured interviews carried out in 2012 that were conducted against a background of longer-term participant-observation, ethnographic studies of drug users and dealers in Philadelphia (2007–12) and of users in San Francisco (1994–2007, 2012). Our findings suggest three types of previously unconsidered influences on overdose risk that arise both from structural socio-economic factors and from the physical properties of the heroin source-types: 1) retail market structure including information flow between users; 2) marketing techniques such as branding, free samples and pricing and 3) differences in the physical characteristics of the two major heroin source forms and how they affect injecting techniques and vascular health. Although chosen for their contrasting source-forms, we found that the two cities have contrasting dominant models of drug retailing: San Francisco respondents tended to buy through private dealers and Philadelphia respondents frequented an open-air street market where heroin is branded and free samples are distributed, although each city included both types of drug sales. These market structures and marketing techniques shape the availability of information regarding heroin potency and its dissemination among users who tend to seek out the strongest heroin available on a given day. The physical characteristics of these two source-types, the way they are prepared for injecting and their effects on vein health also differ markedly. The purpose of this paper is to examine some of the unexplored factors that may lead to heroin-related overdose in the United States and to generate hypotheses for further study. [ABSTRACT FROM AUTHOR]

Abstract: The performance of Calpine''s Geysers steam field from startup in 1960 to 2008 is described in this paper. Since October 2003, Calpine has received approximately 482L/s of tertiary-treated reclaimed water from the City of Santa Rosa. To accommodate and derive benefit from this water, Calpine has converted 20 wells (ten producers, six shut-in, two observation, and two suspended wells) to high-rate injection service. Additional nine wells were also converted to low-rate injectors that receive 12.6L/s or less. Annual recovery factors (i.e., fieldwide increase in annual steam production divided by annual injection) for the first 5 years of Santa Rosa Geysers Recharge Project (SRGRP) operation have been estimated at 17.6%, 26.1%, 37.1%, 39% and 44.6%, respectively; reasonably close to or slightly higher than the values, predicted prior to SRGRP startup. Using a revised definition that includes the amount of un-boiled water in the reservoir, the annual recovery factors turn out to be 17.6%, 16.1%, 14.6%, 12.4% and 12.2% from year one through year five. Improvements in the wellfield, water injection, and power plant modifications from January 1995 through December 2008 are also discussed in this paper. [Copyright &y& Elsevier]

Airport choice is an important air travel-related decision in multiple airport regions. This paper proposes the use of a probabilistic choice set multinomial logit (PCMNL) model for airport choice that generalizes the multinomial logit model used in all earlier airport choice studies. The paper discusses the properties of the PCMNL model, and applies it to examine airport choice of business travelers residing in the San Francisco Bay Area. Substantive policy implications of the results are discussed. Overall, the results indicate that it is important to analyze the choice (consideration) set formation of travelers. Failure to recognize consideration effects of air travelers can lead to biased model parameters, misleading evaluation of the effects of policy action, and a diminished data fit. [Copyright &y& Elsevier]

This paper compares the distribution of damage from the San Fernando, 1971, and Northridge, 1994, earthquakes. Both events had similar size, occurred on blind thrust faults beneath the densely populated San Fernando Valley of the Los Angeles metropolitan area, and hence offer a rare opportunity to compare the effects of the two earthquakes. In a previous study of the distribution of red-tagged (‘unsafe’) buildings and of breaks in the water distribution system caused by the Northridge earthquake, the authors discovered that buildings were damaged less where the soil response was not linear (as indicated by the breaks in the water pipes), except in localized areas of very severe shaking (peak ground velocity exceeding 150 cm/s). The study in this paper shows that the same applies to the damage caused by the San Fernando earthquake, and that the areas with severely damaged buildings (so called ‘gray zones’) for both earthquakes overlapped. This reoccurrence of damage within the same area is interpreted to result from some specific properties of local soil and geology. These properties are not fully understood at present, but should be explored to provide a basis for a new tool for forecasting microzonation maps, and reducing future seismic hazard. [Copyright &y& Elsevier]

This paper focuses on the two related issues of employment distribution and access to transit services. Using the 2001 census tract level economic activities and transit routes within the county, a number of analyses were performed to determine the location of major employment centers in Los Angeles County and how these localities may be understood within the context of a transit service operation in a polycentric metropolitan area. The identified economic subcenters contain one-third of the county employment and its firms, collectively. While these economic nodes are networked by the existing bus routes, the connection between employees and their place of work appears to be inadequate. This has created a less than optimal condition in many sections of the metropolitan area. This paper suggests methodologies for encountering this shortcoming. [Copyright &y& Elsevier]

This paper discusses the electricity reforms in California and in England and Wales. In both cases, a centralised spot market played a major role, and both markets have now been abolished. This paper argues that their disappearance is not evidence that future electricity restructuring should avoid the use of spot markets. Instead, the problems in England and Wales were largely due to market power. In California, problems arising from market power and a tightening demand-supply balance were turned into a disaster because the spot market had not been backed up by hedging contracts. [Copyright &y& Elsevier]

Santa Monica Bay is an open coastal embayment located directly seaward of Los Angeles, California. The Bay provides vital economic value through its water-dependent activities, such as swimming, diving, boating, and fishing. An increase from 100,000 residents in 1900 to 10 million in 2000 has imposed numerous environmental stressors on the Bay, including urbanization of the watershed. Pollutant discharges into the Bay increased throughout the early part of the century, but declined following passage of the Clean Water Act in 1972. Since that time, the predominant source of pollutant inputs has changed from point sources to non-point urban runoff. To assess how present-day and historical pollution interact to affect the environmental quality of Santa Monica Bay, three organizations collaborated on a multi-disciplinary study in 1997, towards which this volume is focused. This paper details the temporal patterns of anthropogenic influence on Santa Monica Bay to provide context for the papers that follow. [Copyright &y& Elsevier]

This paper presents a procedure for the evaluation of the seismic damage in steel moment frame buildings. The rotational capacities, of typical connections of a building in the Los Angeles area, which suffered extensive damage during the Northridge earthquake, were determined using stress triaxiality as an indicator for fracture. The rotational demands of the same connections were obtained from a three-dimensional finite element analysis of the building model. Comparisons of the rotational demands at several locations in the building to the rotational capacities determined by the stress triaxiality analysis showed that fracture of steel moment connections of the building are governed by the triaxiality of stresses. Based on a number of moment connections analyzed, the paper suggests a moment capacity equation for the pre-Northridge welded steel moment connections taking into account the fracture incidence due to stress triaxiality effect. The moment capacity of such connections as dictated by stress triaxiality compared favorably to FEMA-350 requirements. [Copyright &y& Elsevier]

A high resolution, data assimilating ocean model of the Monterey Bay area (ICON model) is under development within the framework of the project “An Innovative Coastal-Ocean Observing Network” (ICON) sponsored by the National Oceanographic Partnership Program. The main objective of the ICON model development is demonstration of the capability of a high resolution model to track the major mesoscale ocean features in the Monterey Bay area when constrained by the measurements and nested within a regional larger-scale model.This paper focuses on the development of the major ICON model components, including grid generation and open boundary conditions, coupling with a larger scale, Pacific West Coast (PWC) model, atmospheric forcing etc. Impact of these components on the Model''s predictive skills in reproducing major hydrographic conditions in the Monterey Bay area are analyzed.Comparisons between observations and the ICON model predictions with and without coupling to the PWC model, show that coupling with the regional model improves significantly both the correlation between the ICON model and observed ADCP currents, and the ICON model''s skill in predicting the location and intensity of observed upwelling events.Analysis of the ICON model mixed layer depth predictions show that the ICON model tends to develop a thicker than observed mixed layer during the summer time, and while assimilation of sea surface temperature data is enough for development of observed thin mixed layer in the regional larger-scale model, the fine-resolution ICON model needs variable heat fluxes as surface boundary conditions for the accurate prediction of the vertical thermal structure.The paper targets researchers involved in high-resolution numerical modeling of coastal areas in which the dynamics are determined by the complex geometry of a coastline, variable bathymetry and by the influence of complex water masses from a complicated hydrographic system (such as the California Current system). [Copyright &y& Elsevier]

Creating local population health measures from administrative data would be useful for health policy and public health monitoring purposes. While a wide range of options--from simple spatial smoothers to model-based methods--for estimating such rates exists, there are relatively few side-by-side comparisons, especially not with real-world data. In this paper, we compare methods for creating local estimates of acute myocardial infarction rates from Medicare claims data. A Bayesian Monte Carlo Markov Chain estimator that incorporated spatial and local random effects performed best, followed by a method-of-moments spatial Empirical Bayes estimator. As the former is more complicated and time-consuming, spatial linear Empirical Bayes methods may represent a good alternative for non-specialist investigators. [ABSTRACT FROM AUTHOR]

• Renewable hydrogen can compete with lithium-ion batteries for seasonal storage. • Hydrogen's competitiveness depends on heat rate of plant it is replacing. • Net present value of hydrogen-fired gas turbine varies based on operation of plant. • Lack of infrastructure will impede demand growth for hydrogen in the United States. Non-emitting variable renewable energy (VRE) resources are needed on the power grid if the United States is to "deeply decarbonize" the power sector. The intermittent nature of these resources makes them difficult to integrate into the power system. Existing energy storage technologies, such as lithium-ion (LI) batteries, could be used to aid the integration of these resources, but these technologies are sized to produce power for hours at a time before needing to be charged again. While these energy storage technologies could address daily imbalances between supply and demand for electric power, they cannot address the seasonal nature of power production of VREs. This paper details a methodology to estimate the levelized cost of energy (LCOE) of meeting this seasonal imbalance with either a hydrogen-fired gas turbine (HFGT) or lithium-ion battery system (LI) as a measure of economic efficiency of the technologies. Applying our model, we find the average LCOE associated with meeting this seasonal imbalance is $2400/MWh using a HFGT fueled with green hydrogen and $3000/MWh using a LI. If we allow the model to operate the HFGT with blue hydrogen the average LCOE decreases to $1560/MWh. However, we find the power prices required to justify investment in an HFGT to replace a natural gas-fired gas turbine are considerably higher than those seen in the market today. [ABSTRACT FROM AUTHOR]

Abstract: Over the past twenty-five years, more workers in the United States have been given the option of flexible work schedules, which are designed to redistribute commuter traffic over the course of a day by allowing employees to vary their arrival and/or departure times. This paper examines whether and to what degree access to flexible work schedules affects the departure times of commuters in the two largest and most congested areas of California: the Los Angeles and San Francisco regions. Trip data were obtained from the 2009 US National Household Travel Survey (NHTS). The results of this study show that people who have access to flexitime preferred later departure times rather than earlier times. Workers with flexible schedules were 3.30% less likely to depart before peak hours, 4.11% less likely during peak hours, and 7.41% more likely afterwards. Based on these findings, government agencies and private firms in regions with severe traffic congestion problems may consider adopting alternative work schedules. [Copyright &y& Elsevier]

Abstract: In the western U.S., numerous exposures of Precambrian crustal rocks were exhumed from mid-crustal depths during Cenozoic tectonic events and provide a view into the deep crust. This natural laboratory provides an excellent opportunity to study orogenic and continent-forming processes at deeper levels. The Ivanpah Mountains of southeastern California contain exposures of Paleoproterozoic migmatites and banded gneisses that belong to the Mojave crustal province. New, detailed U–Pb geochronology of monazite and zircon from ortho- and paragneisses reveal the timing of the formation of these rocks and multiple periods of metamorphism and magmatism. Paragneisses have detrital zircon populations of dominantly 1.80–2.15Ga (dominant) and 2.4–2.8Ga, although the youngest detrital zircon grain is 1.754±24Ga. Values of δ 18O(zircon) of the two detrital age populations are 7.0±2.2‰ and 6.3±1.4‰ (2SD), respectively, consistent with original, igneous values. Based on the 1.76Ga age of metamorphic zircon rims, the metasediments were intruded by a calc-alkaline magmatic suite including gabbro, tonalite, and porphyritic granite at 1.76Ga, although the contacts are obscured by pervasive metamorphism and deformation. U–Pb ages of metamorphic overgrowths on detrital zircons from the paragneisses indicate multiple events at ∼1.76, 1.74, 1.70 and 1.67Ga which documents a periodicity of tectonism through time. The oxygen isotope ratios of the metamorphic zircon overgrowths from the paragneisses remained relatively constant through time within each sample, consistent with growth during in situ partial melting. However, oxygen isotope ratios of zircons from 1.74Ga leucocratic material are lower in δ 18O, and therefore could not have been generated by partial melting of the adjacent paragneiss. Monazite from both igneous and metasedimentary rocks preserves two periods of growth at 1.75 and 1.67Ga. In situ, U–Pb dating of monazite reveals that 1.67Ga monazite inclusions are found in major rock-forming minerals, and therefore we interpret this as the timing of fabric formation and migmitization, which is younger than previously believed and is interpreted to be the dominant metamorphic pulse in the protracted middle crustal tectonism. Thermobarometry indicates peak metamorphic conditions of ∼3.5kb and ∼740°C, which is consistent with partial melting and the metamorphic mineral assemblage in these rocks (sillimanite+K-feldspar, muscovite absent). This paper shows (1) multiple pulses identified within 100Ma orogeny, (2) zircon components and their overgrowths demonstrate mixing of Archean, 1.8 and younger reservoirs, (3) low pressure granulite facies metamorphism occurred at 1.67Ga and may have been related to continental extension of a tectonically over-thickened crust. [Copyright &y& Elsevier]

Abstract: Minimum parking requirements (MPRs) are the norm for urban and suburban development in the United States (). The justification for MPRs is that overflow parking will occupy nearby street or off-street parking. and provide cases where there is reason to believe that parking space requirements have forced parcel developers to place more parking than they would in the absence of parking requirements. However, to our knowledge the existing literature does not test the effect of parking minimums on the amount of lot space devoted to parking beyond a few case studies. This paper tests the hypothesis that MPRs bind for most land uses using data on suburban office, commercial, industrial and retail property sales from Los Angeles County using both direct and indirect approaches. Our indirect test of the effects of parking requirements is similar to the one used by . A simple theoretical model shows that the marginal value of additional parking to the sale price of a building should be equal to the cost of land plus the cost of parking construction. We estimate the marginal values of parking and lot area with spatial methods using a large data set from the Los Angeles area non-residential property sales and find that for most of the property types the marginal value of parking is significantly below that of the parcel area. In addition, we directly examine required and supplied parking and find that on average parking supplied is quite close to the required amount. [Copyright &y& Elsevier]

Abstract: A multistate Escherichia coli O157:H7 outbreak in August and September 2006 was found to be associated with consumption of fresh bagged spinach traced to California. The California Food Emergency Response Team (CALFERT), consisting of personnel from the California Department of Public Health Food and Drug Branch (FDB) and the U.S. Food and Drug Administration (FDA) undertook an environmental investigation to determine how and why the spinach became contaminated. At the invitation of FDA and FDB, the Centers for Disease Control and Prevention (CDC) also participated in the environmental investigation. This paper presents findings from the portion of the environmental investigation focusing on environmental factors related to irrigation water that may have contributed to contamination of the spinach and hence to the outbreak. Analysis of the available data suggests that depths to groundwater and groundwater–surface water interactions may pose risks to ready-to-eat crops. These risks should be further evaluated and quantified to understand and identify the factors that contributed to this and similar outbreaks. One implication of this analysis is the need to continue to conceptually broaden the scope of produce-related outbreak investigations. Where feasible, investigation strategies should integrate possible contamination sources beyond those actually found on the farms that are identified as sources of produce involved in outbreaks. [Copyright &y& Elsevier]

Abstract: In this paper, I analyze immigration''s effect on the SAT-scores and college application patterns of high school students in California and Texas. The student-level dataset used is longitudinal in nature and is matched via a unique algorithm to the Census 2000 summary tabulation files to determine immigration at the local census-place level. The Census measure of immigration developed here is extremely specific and improves upon existing immigration measures. Using empirical strategies to account for issues of selection, this essay''s main finding is that the 1990s immigration did not harm, and possibly benefited the student outcomes of U.S. citizens. [Copyright &y& Elsevier]

Abstract: Glider observations were essential components of the observational program in the Autonomous Ocean Sampling Network (AOSN-II) experiment in the Monterey Bay area during summer of 2003. This paper is focused on the impact of the assimilation of glider temperature and salinity observations on the Navy Coastal Ocean Model (NCOM) predictions of surface and subsurface properties. The modeling system consists of an implementation of the NCOM model using a curvilinear, orthogonal grid with 1–4km resolution, with finest resolution around the bay. The model receives open boundary conditions from a regional (9km resolution) NCOM implementation for the California Current System, and surface fluxes from the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) atmospheric model at 3km resolution. The data assimilation component of the system is a version of the Navy Coupled Ocean Data Assimilation (NCODA) system, which is used for assimilation of the glider data into the NCOM model of the Monterey Bay area. The NCODA is a fully 3D multivariate optimum interpolation system that produces simultaneous analyses of temperature, salinity, geopotential, and vector velocity. Assimilation of glider data improves the surface temperature at the mooring locations for the NCOM model hindcast and nowcasts, and for the short-range (1–1.5 days) forecasts. It is shown that it is critical to have accurate atmospheric forcing for more extended forecasts. Assimilation of glider data provided better agreement with independent observations (for example, with aircraft measured SSTs) of the model-predicted and observed spatial distributions of surface temperature and salinity. Mooring observations of subsurface temperature and salinity show sharp changes in the thermocline and halocline depths during transitions from upwelling to relaxation and vice versa. The non-assimilative run also shows these transitions in subsurface temperature; but they are not as well defined. For salinity, the non-assimilative run significantly differs from the observations. However, the glider data assimilating run is able to show comparable results with observations of thermocline as well as halocline depths during upwelling and relaxation events in the Monterey Bay area. It is also shown that during the relaxation of wind, the data assimilative run has higher value of subsurface velocity complex correlation with observations than the non-assimilative run. [Copyright &y& Elsevier]

Abstract: This paper investigates the transport structure of surface currents around the Monterey Bay, CA region. Currents measured by radar stations around Monterey Bay indicate the presence of strong, spatial and temporal, nonlinear patterns. To understand the geometry of the flow in the bay, Lagrangian coherent structures (LCS) are computed. These structures are mobile separatrices that divide the flow into regions of qualitatively different dynamics. They provide direct information about the flow structure but are geometrically simpler than particle trajectories themselves. The LCS patterns were used to reveal the mesoscale flow conditions observed during the 2003 Autonomous Ocean Sampling Network (AOSN-II) experiment. Drifter paths from the AOSN experiment were compared to the patterns induced by the LCS computed from high-frequency radar data. We verify that the fate of the drifters can be better characterized based on the LCS than direct interpretation of the current data. This property can be exploited to optimize drifter deployment. [Copyright &y& Elsevier]

Abstract: Efforts to model the potential habitat and risk for spread of invasive diseases such as Sudden Oak Death (SOD) are important for disease regulation and management. However, spatially referenced risk models using identical data can have differing results, making decision-making based on the mapped results problematic. We examined the results from five spatial risk models generated from common input parameters, and investigated model agreement for mapping risk for the causal pathogen for SOD, Phytophthora ramorum across the conterminous United States. We examined five models: Expert-driven Rule-based, Logistic Regression, Classification and Regression Trees, Genetic Algorithms, and Support Vector Machines. All models were consistent in their prediction of some SOD risk in coastal California, Oregon and Washington states, and in the northern foothills of the Sierra Nevada Mountains in California, and in an east–west oriented band including eastern Oklahoma, central Arkansas, Tennessee, Kentucky, northern Mississippi, Alabama, Georgia and South Carolina, parts of central North Carolina, and eastern Virginia, Delaware and Maryland states. The SVM model was the most accurate model, and had several advantages over the other models. Although theoretical in nature, this paper presents results that have practical, applied value for managers and regulators of this disease, and discusses common challenges in modeling invasive species niches over large scales. [Copyright &y& Elsevier]

Abstract: Despite the health and survival advantages of Hispanics relative to non-Hispanic whites in the USA, Hispanics report themselves to be in worse health than whites. Prior research indicates that these ethnic differences in self-rated health (SRH), measured by a simple question asking individuals to assess their overall health status, persist in the presence of an extensive set of explanatory variables. In this paper we use data from the first wave of the Los Angeles Family and Neighborhood Survey (L.A.FANS-1) to test three hypotheses regarding Hispanic–white differences in SRH. We evaluate whether poorer health reports among Hispanics result from: (1) acculturation and language-related differences in reports; (2) measures of socioeconomic status (SES) that are often omitted in other studies; and (3) somatization of emotional distress by Hispanics. Our results provide new insights into the validity of these explanations and suggest avenues for future research. First, they underscore the importance of language of interview over other measures of acculturation, suggesting that translation issues between the Spanish and English versions of the SRH question may give rise to some of the differences. Second, adjustment for SES—especially years of schooling—narrows, but does not eliminate, the gap between whites’ and Hispanics’ SRH. Finally, although respondents who are depressed are more likely to report poor SRH, this study provides little evidence to support the somatization hypothesis. The second wave of L.A.FANS incorporates new questions that are likely to permit more in-depth assessments of these hypotheses in future analyses. [Copyright &y& Elsevier]

Abstract: The Northridge earthquake (near Los Angeles, CA, USA, January 17, 1994) and the Tecomán–Colima earthquake (near Manzanillo, México, January 21, 2003) have increased our knowledge of the behavior of masonry buildings in significant earthquakes, and also have led to changes or proposals for changes in US masonry design provisions. In this paper, the masonry code-development process in the US is briefly reviewed, with emphasis on the fundamental role of the Masonry Standards Joint Committee (MSJC). The Northridge and Tecomán–Colima earthquakes are discussed, with emphasis on the behavior of modern engineered masonry. Lessons learned from those earthquakes with regard to masonry are summarized, and the related evolution of MSJC design provisions for the US is discussed. [Copyright &y& Elsevier]

Cost effectiveness for consumers of solar electric systems has been achieved in the California residential market due to Time-of-Use Net Metering, a tiered electric rate structure with high rates, and subsidies by the state government.Three different approaches test and validate this hypothesis for a large fraction of consumers. Solar electricity can generate rates of return of 11–20% exceeding most other common investments, can increase property value by more than the cost to install the system, and generate a positive cash flow if financed.This paper suggests further study in the commercial sector and a survey to document evidence of increased home resale value. [Copyright &y& Elsevier]

Recent work on health and place has examined the impact of the environment on health. At the local level, research has followed several strands, such as contextual effects of neighborhoods, the impact of differential access to services and amenities, effects of a neighborhood''s collective efficacy, and the relationship between social capital and health. Of these four approaches, social capital has generated the most debate; some scholars discuss social capital as a key epidemiological variable, while others discount or dismiss its utility. We undertook this research to assess whether the concept of social capital could increase our understanding of the impact of neighborhoods on residents’ health. We utilized key informant interviews and focus groups to understand ways in which residents of diverse neighborhoods in one large California city perceived that their local communities were affecting health. We argue in this paper that using the term “social capital” to discuss social resources and their mobilization in a particular neighborhood highlights the ways in which social resources can vary in relation to economic resources, and that residents of neighborhoods with differing levels of services and amenities face different issues when mobilizing to improve their neighborhoods. Additionally, the projects that people invest in vary by neighborhood socioeconomic status. We draw on the paired concepts of “bridging” and “bonding” social capital, and discuss that while stores of bonding social capital may be more uniform across neighborhoods of varying SES, bridging social capital tends to be found in greater amounts in neighborhoods of higher SES which allows them greater success when mobilizing to improve their neighborhoods. [Copyright &y& Elsevier]

About 200 samples from selected public supply, domestic, and observation wells completed in alluvial aquifers underlying the western Mojave Desert were analyzed for total dissolved Cr and Cr(VI). Because Cr(VI) is difficult to preserve, samples were analyzed by 3 methods. Chromium(VI) was determined in the field using both a direct colorimetric method and EPA method 218.6, and samples were speciated in the field for later analysis in the laboratory using a cation-exchange method developed for the study described in this paper. Comparison of the direct colorimetric method and EPA method 218.6 with the new cation-exchange method yielded r2 values of 0.9991 and 0.9992, respectively. Total dissolved Cr concentrations ranged from less than the 0.1 μg/l detection limit to 60 μg/l, and almost all the Cr present was Cr(VI). Near recharge areas along the mountain front pH values were near neutral, dissolved O2 concentrations were near saturation, and Cr(VI) concentrations were less than the 0.1 μg/l detection limit. Chromium(VI) concentrations and pH values increased downgradient as long as dissolved O2 was present. However, low Cr(VI) concentrations were associated with low dissolved O2 concentrations near ground-water discharge areas along dry lakes. Chromium(VI) concentrations as high as 60 μg/l occurred in ground water from the Sheep Creek fan alluvial deposits weathered from mafic rock derived from the San Gabriel Mountains, and Cr(VI) concentrations as high as about 36 μg/l were present in ground water from alluvial deposits weathered from less mafic granitic, metamorphic, and volcanic rocks. Chromium(III) was the predominant form of Cr only in areas where dissolved O2 concentrations were less than 1 mg/l and was detected at a median concentration of 0.1 μg/l, owing to its low solubility in water of near-neutral pH. Depending on local hydrogeologic conditions and the distribution of dissolved O2, Cr(VI) concentrations may vary considerably with depth. Samples collected under pumping conditions from different depths within wells show that Cr(VI) concentrations can range from less than the 0.1 μg/l detection limit to 36 μg/l in a single well and that dissolved O2 concentrations likely control the concentration and redox speciation of Cr in ground water. [Copyright &y& Elsevier]

In this paper we present a parallel regret insertion heuristic to solve a dial-a-ride problem with time windows. A new route initialization procedure is implemented, that keeps into account both the spatial and the temporal aspects of the problem, and a regret insertion is then performed to serve the remaining requests. The considered operating scenario is representative of a large-scale dial-a-ride program in Los Angeles County. The proposed algorithm was tested on data sets of 500 and 1000 requests built from data of paratransit service in this area. The computational results show the effectiveness of this approach in terms of trading-off solution quality and computational times. The latter measure being especially important in large-scale systems where numerous daily requests need to be processed. [Copyright &y& Elsevier]

Building occupants, including cleaning personnel, are exposed to a wide variety of airborne chemicals when cleaning agents and air fresheners are used in buildings. Certain of these chemicals are listed by the state of California as toxic air contaminants (TACs) and a subset of these are regulated by the US federal government as hazardous air pollutants (HAPs). California''s Proposition 65 list of species recognized as carcinogens or reproductive toxicants also includes constituents of certain cleaning products and air fresheners. In addition, many cleaning agents and air fresheners contain chemicals that can react with other air contaminants to yield potentially harmful secondary products. For example, terpenes can react rapidly with ozone in indoor air generating many secondary pollutants, including TACs such as formaldehyde. Furthermore, ozone–terpene reactions produce the hydroxyl radical, which reacts rapidly with organics, leading to the formation of other potentially toxic air pollutants. Indoor reactive chemistry involving the nitrate radical and cleaning-product constituents is also of concern, since it produces organic nitrates as well as some of the same oxidation products generated by ozone and hydroxyl radicals.Few studies have directly addressed the indoor concentrations of TACs that might result from primary emissions or secondary pollutant formation following the use of cleaning agents and air fresheners. In this paper, we combine direct empirical evidence with the basic principles of indoor pollutant behavior and with information from relevant studies, to analyze and critically assess air pollutant exposures resulting from the use of cleaning products and air fresheners. Attention is focused on compounds that are listed as HAPs, TACs or Proposition 65 carcinogens/reproductive toxicants and compounds that can readily react to generate secondary pollutants. The toxicity of many of these secondary pollutants has yet to be evaluated. The inhalation intake of airborne organic compounds from cleaning product use is estimated to be of the order of 10 mg d−1 person−1 in California. More than two dozen research articles present evidence of adverse health effects from inhalation exposure associated with cleaning or cleaning products. Exposure to primary and secondary pollutants depends on the complex interplay of many sets of factors and processes, including cleaning product composition, usage, building occupancy, emission dynamics, transport and mixing, building ventilation, sorptive interactions with building surfaces, and reactive chemistry. Current understanding is sufficient to describe the influence of these variables qualitatively in most cases and quantitatively in a few. [Copyright &y& Elsevier]

One of the challenges for power industry restructuring is to maintain sufficient generation installed capacity to meet demand in nowadays and in the future, and the electricity market failure in California has brought this subject to the forefront of extensive debates. This paper initiates a review, assessment and discussion on some important issues related to ensuring adequate generation capacity additions under a competitive electricity market environment. [Copyright &y& Elsevier]

Progress was made during the past decade towards a better understanding of halo formation caused by beam mismatch in high-intensity beams. To test these ideas an experiment was carried out at Los Alamos with proton beams in a 52-quadrupole focusing channel. Rms emittances and beam widths were obtained from measured beam profiles for comparison with the maximum emittance-growth predictions of a free-energy model and the maximum halo-amplitude predictions of a particle-core model. The experimental results are also compared with multiparticle simulations. In this paper we will present the experimental results and discuss the implications with respect to the validity of both the models and the simulations. [Copyright &y& Elsevier]

The modern analog technique (MAT) is a quantitative calibration tool for using modern pollen assemblages to interpret fossil pollen assemblages for vegetation and climate reconstruction. When the MAT is applied using multivariate distance metrics, a cutoff value for the metric is often used to determine the presence/absence of analogs in a modern pollen reference set. Two kinds of error arise when a cutoff value is used: (1) false positive error, which occurs when analogy is falsely determined to exist between the vegetation (or other parameter) of a sample of interest and that of a sample in the reference set; and (2) false negative error, which occurs when analogy is falsely determined not to exist. The existing literature focuses primarily on examining cutoff thresholds from the perspective of reducing false positive error, with relatively little attention paid to false negative error and to the inherent trade-off between the two errors. This paper sets forth a general analytical framework for determining cutoff thresholds that minimize the joint occurrence of the two errors, and employs the squared chord distance metric with a newly developed reference set of modern pollen surface samples from southern California, USA, as a demonstration case. It also examines the nature of the tradeoffs that occur if an analyst decides to accept increased risk (beyond the joint minimum) of one of the kinds of error for additional reduction of the other. An asymmetric tradeoff in these risks above and below the joint error minimizing cutoff(s) is described (a more rapid proportionate increase of false negatives at cutoffs below the joint minimum in relation to the proportionate increase of false positives at cutoffs above it), which is controlled by the relative variances of the distributions of like- and non-like-vegetation sample comparisons in terms of the distance metric. This asymmetry is found to be general among sample sets reported using the squared chord distance, but is not general across other distance metrics. [Copyright &y& Elsevier]

The East Bay Children''s Respiratory Health Study is examining associations between traffic-related pollutant exposures and respiratory health among children who reside and attend schools at varied proximity to northern California freeways. Chronic exposures are being inferred from outdoor pollutant concentrations at neighborhood schools. This paper reports primarily weeklong integrated NO2 and NOX concentrations measured with passive samplers placed outside at 10 elementary schools during 14 weeks in spring and 8 weeks in fall 2001. Measurements were also made outside selected student residences to examine spatial variability within three school neighborhoods. Regional concentrations of NO2 and NOX varied widely from week to week. School site data were normalized to measurements at a nearby regional monitoring station to facilitate analysis of relative pollutant exposures at the neighborhood schools. Normalized concentrations were consistent at each school throughout the study. Schools located upwind or far downwind of freeways were generally indistinguishable from one another and regional pollution levels. For school and neighborhood sites within 350 m downwind of a freeway, concentrations increased with decreasing downwind distance. The highest normalized concentrations occurred at a school located directly adjacent to a major freeway and a shopping center. In this case, normalized NO2 and NOX were ∼60% and ∼100% higher than regional background levels. At three schools within 130–230 m downwind of a freeway, normalized NO2 and NOX were ∼20–30% and ∼50–80% higher than regional levels. Validation testing of the passive samplers indicated precision of better than 5% for both NO2 and NOX when samplers were deployed outside for 1-week periods. Passive sampler results agreed with co-located chemiluminescence measurements to within 8% for NO2 and 3% for NOX. [Copyright &y& Elsevier]

Current modeling methods are inadequate for producing gridded mobile source inventories suitable for simulating fine-scale changes in emissions for transportation planning or regulatory control purposes. In this paper, we present a new model that more precisely simulates small-scale emission changes that can arise from, for example, implementation of traffic control measures in transportation networks. The new model, UCDrive, directly interfaces with most travel demand models and with California''s regulatory emission factor model EMFAC2001/2002. The model improves the sensitivity of emission estimates to variations in vehicle speeds and uses a theoretically consistent approach to spatially disaggregating mobile emissions. To demonstrate application of the model we use the Sacramento area network to perform a comparison study. We show that regional emissions with the new model replicate regulatory inventories, which is critical for using the model for regulatory purposes. We also show that the new model''s results better replicate regulatory totals than those derived with a frequently used gridded emissions inventory model. The new model should improve the ability to better simulate changes in mobile emissions from transportation projects and help to bridge the gap between gridded mobile emission inventories and regional mobile emission inventories. [Copyright &y& Elsevier]

: PurposeTo calculate the cost structure of a suite of immunization improvement interventions recommended by the Centers for Disease Control and Prevention (CDC).: MethodsA determination was made of the cost to clinics and agencies that implement a suite of CDC-recommended practice improvement interventions to fully immunize a child for diphtheria–tetanus–attenuated pertussis (DTaP), inactivated poliovirus (IPV), and measles–mumps–rubella (MMR) vaccines. Patient data were collected through chart analysis of 16-month-old children in clinics participating in this study''s interventions between May 1997 and August 2000. The study began on October 1, 1996, and was funded for 5 years (until September 30, 2002).: ResultsStudy calculations suggest that an additional $0.013/per patient per month would be needed to cover these activities.: ConclusionsIdentifiable cost structures are associated with the practice improvement strategies recommended by the CDC. The method of implementation may be as important as the interventions themselves. Present compensation for immunization may not actually cover the cost of service provision, and it is unlikely to cover the costs of practice improvement, as described in this paper. [Copyright &y& Elsevier]

Quaternary volcanic unrest has provided heat for episodic hydrothermal circulation in the Long Valley caldera, including the present-day hydrothermal system, which has been active over the past 40 kyr. The most recent period of crustal unrest in this region of east-central California began around 1980 and has included periods of intense seismicity and ground deformation. Uplift totaling more than 0.7 m has been centered on the caldera’s resurgent dome, and is best modeled by a near-vertical ellipsoidal source centered at depths of 6–7 km. Modeling of both deformation and microgravity data now suggests that (1) there are two inflation sources beneath the caldera, a shallower source 7–10 km beneath the resurgent dome and a deeper source ∼15 km beneath the caldera’s south moat and (2) the shallower source may contain components of magmatic brine and gas. The Long Valley Exploration Well (LVEW), completed in 1998 on the resurgent dome, penetrates to a depth of 3 km directly above this shallower source, but bottoms in a zone of 100°C fluid with zero vertical thermal gradient. Although these results preclude extrapolations of temperatures at depths below 3 km, other information obtained from flow tests and fluid sampling at this well indicates the presence of magmatic volatiles and fault-related permeability within the metamorphic basement rocks underlying the volcanic fill. In this paper, we present recently acquired data from LVEW and compare them with information from other drill holes and thermal springs in Long Valley to delineate the likely flow paths and fluid system properties under the resurgent dome. Additional information from mineralogical assemblages in core obtained from fracture zones in LVEW documents a previous period of more vigorous and energetic fluid circulation beneath the resurgent dome. Although this system apparently died off as a result of mineral deposition and cooling (and/or deepening) of magmatic heat sources, flow testing and tidal analyses of LVEW water level data show that relatively high permeability and strain sensitivity still exist in the steeply dipping principal fracture zone penetrated at a depth of 2.6 km. The hydraulic properties of this zone would allow a pressure change induced at distances of several kilometers below the well to be observable within a matter of days. This indicates that continuous fluid pressure monitoring in the well could provide direct evidence of future intrusions of magma or high-temperature fluids at depths of 5–7 km. [Copyright &y& Elsevier]

This paper reviews sea level and elevated surface observations from Point Mugu and nearby Laguna Peak in southern Ventura County, rawin/ozonesonde data from Point Mugu, and aircraft measurements in the coastal zone and offshore obtained in support of the SCOS97-NARSTO effort. Streamline analyses of SCOS97-NARSTO wind data are also presented, which reveal synoptic and mesoscale influences on air flow over the southern California area. Complex diurnal, mesoscale and synoptic wind patterns redistribute pollutants across air basins. The data show that southeasterly flow, often present from morning into early afternoon, and coastal eddies and southerly surges convey ozone and precursors westward and northward where they may appear aloft as layers with several times the concentration of ozone at the surface. This flow can transport South Coast Air Basin (SCAB) pollutants via mountain passes to the desert where mixing with pollution from the San Joaquin Valley can occur. Climatological evidence shows this tendency for southerly flow in the earlier part of the day is a recurrent feature of southern California wind patterns, and a major mechanism for transport of ozone and precursors from the SCAB to coastal, inland and desert regions to the north. [Copyright &y& Elsevier]

Santa Monica Bay was mapped in 1996 using a high-resolution multibeam system, providing the first substantial update of the submarine geomorphology since the initial compilation by Shepard and Emery [(1941) Geol. Soc. Amer. Spec. Paper 31]. The multibeam mapping generated not only high-resolution bathymetry, but also coregistered, calibrated acoustic backscatter at 95 kHz. The geomorphology has been subdivided into six provinces; shelf, marginal plateau, submarine canyon, basin slope, apron, and basin. The dimensions, gradients, and backscatter characteristics of each province is described and related to a combination of tectonics, climate, sea level, and sediment supply. Fluctuations of eustatic sea level have had a profound effect on the area; by periodically eroding the surface of Santa Monica plateau, extending the mouth of the Los Angeles River to various locations along the shelf break, and by connecting submarine canyons to rivers. A wetter glacial climate undoubtedly generated more sediment to the rivers that then transported the increased sediment load to the low-stand coastline and canyon heads. The trends of Santa Monica Canyon and several bathymetric highs suggest a complex tectonic stress field that has controlled the various segments. There is no geomorphic evidence to suggest Redondo Canyon is fault controlled. The San Pedro fault can be extended more than 30 km to the northwest by the alignment of a series of bathymetric highs and abrupt changes in direction of channel thalwegs. [Copyright &y& Elsevier]

This paper presents the applications of a recently developed pattern classifier called support vector machine (SVM) in incident detection. Support vector machine is constructed from a unique learning algorithm that extracts training vectors that lie closest to the class boundary, and makes use of them to construct a decision boundary that optimally separates the different classes of data. Two SVMs, each with a different non-linear kernel function, were trained and tested with simulated incident data from an arterial network. Test results have shown that SVM offers a lower misclassification rate, higher correct detection rate, lower false alarm rate and slightly faster detection time than the multi-layer feed forward neural network (MLF) and probabilistic neural network models in arterial incident detection. Three different SVMs have also been developed and tested with real I-880 Freeway data in California. The freeway SVMs have exhibited incident detection performance as good as the MLF, one of the most promising incident detection model developed to date. [Copyright &y& Elsevier]

This paper examines the deployment of electronic toll collection (ETC) and develops a model to maximize social welfare associated with a toll plaza. A payment choice model estimates the share of traffic using ETC as a function of delay, price, and a fixed cost of acquiring the in-vehicle transponder. Delay in turn depends on the relative number of ETC and manual collection lanes. Price depends on the discount given to users of the ETC lanes. The fixed cost of acquiring the transponder (not simply a monetary cost, but also the effort involved in signing up for the program) is a key factor in the model. Once a traveler acquires the transponder, the cost of choosing ETC in the future declines significantly. Welfare depends on the market share of ETC, and includes delay and gasoline consumption, toll collection costs, and social costs such as air pollution. This work examines the best combination of ETC lanes and toll discount to maximize welfare. Too many ETC lanes cause excessive delay to non-equipped users. Too high a discount costs the highway agency revenue needed to operate the facility. The model is applied to California’s Carquinez Bridge, and recommendations are made concerning the number of dedicated ETC lanes and the appropriate ETC discount. [Copyright &y& Elsevier]

With levelized electricity costs (LEC) of 10–12 USCts/kWh the well-known SEGS (Solar Electric Generating Systems) plants in California are presently the most successful solar technology for electricity generation [Price and Cable (2001) Proc. ASME Int. Solar Energy Conf. Forum 2001]. The SEGS plants apply a two-circuit system, consisting of the collector circuit and the Rankine cycle of the power block. These two-circuits are connected via a heat exchanger. In the case of the Direct Steam Generation (DSG) in the collector field [Zarza et al. (2001) Proc. Solar Forum 2001, Washington], the two-circuit system turns into a single-circuit system, where the collector field is directly coupled to the power block. This renders a lower investment and higher process temperatures resulting in a higher system efficiency. Due to the lower investment and the higher efficiency a reduction of the LEC of 10% is expected when the DSG process is combined with improved components of the solar collectors [Zarza (2002) DISS Phase II Final Report, EU Contract No. JOR3-CT98-0277]. Within the European DISS (Direct Solar Steam) project the feasibility of the direct steam generation has been proven in more than 3700 operation hours. Steam conditions of 100 bar and 400 °C have been demonstrated. This paper presents the main scientific results of the DISS project that aims at the investigation and demonstration of the DSG process in parabolic troughs under real solar conditions. [Copyright &y& Elsevier]

The spatial diffusion of poverty and the demographic profile of the “poor” in cities like Los Angeles, where 1.7 million residents of the greater metropolitan area qualify as such, suggest that poverty is neither a socioeconomic exception nor affiliated with a singular sociocultural or racial group. However, our policy discourse and solutions continue to suffer from a modernist/industrial era explanation of poverty and its spatial concentration. In this paper, I will offer an alternative interpretation of economic development in the 20th century and propose that development projects fit comfortably into the political philosophy of nation building and the social construction of citizenship. Under the umbrella of social justice and democracy, many regions of the world, including the inner city, have been envisioned as landscapes of social and political instability and targeted for development as such. Here, the equating of development with stability is examined theoretically to suggest that anti-poverty policies, both in the US and the UK, can be viewed as an extension of the 20th century modernist nation-building agenda. [Copyright &y& Elsevier]

This paper aims to improve current understanding of the subsurface fracture system in the Coso geothermal field, located in east-central California. The Coso reservoir is in active economic development, so that knowledge of the subsurface fracture system is of vital importance for an accurate evaluation of its geothermal potential and day-to-day production. To detect the geometry and density of fracture systems we applied the shear-wave splitting technique to a large number of high-quality seismograms from local microearthquakes recorded by a permanent, 16-station, down-hole, 3-component seismic array running at 480 samples/s. The analysis of shear-wave splitting (seismic birefringence) provides parameters directly related to the strike of the subsurface fractures and their density (number of cracks per unit volume), and, consequently, is an important technique to outline zones of high permeability. Three major fracture directions N10–30W, N0–20E, and N40–50E, of which the first and the second are the most prominent, were identified from the seismograms recorded by the 16-station down-hole array. All orientations are consistent with the known strike of local sets of faults and fractures in local wells and at the surface, as well as with previous analyses of seismic anisotropy in the region. The high quality of the recordings has allowed us to launch an unprecedented investigation into the characteristics of the temporal variations in crack polarization and crack density in a producing geothermal environment. Preliminary results point to significant temporal changes in shear-wave time delays, probably influenced by temporal changes in crack density within a period of 5 years (1996–2000). They are tentatively interpreted as due to a local ∼3% increase in shear-wave velocity in the southwestern part of the field during 1999. [Copyright &y& Elsevier]

Piping elbows under bending are vulnerable to cracking at the crown. Hence it is necessary to estimate the crack driving force. This paper presents a closed form expression for the plastic J-integral for axially through-wall cracked, long radius elbows under opening bending moment. The equation is derived, based on a large number of finite element analyses covering a wide range of geometries. The non-linear finite element analyses were performed using WARP3D software and accounted for geometric and material non-linearity. The material was assumed to follow the Ramberg–Osgood law with a wide range of strain hardening exponent (n=2,3,5,7 and 10). [Copyright &y& Elsevier]

Los Angeles County established its first drug court program in 1994 in response to escalating criminal activity associated with substance abuse and overcrowded jails. This paper describes results of an evaluation of 803 drug court participants admitted to the program between 1994 and 1997. Of all drug court participants, 76% remained free of any new arrests throughout the one-year followup period, compared to 63% of participants in a drug diversion education program and 49% of the felony defendants not exposed to either program. Of offenders completing the drug court program 80% had no arrests, compared to 67% for non-completers. Drug related re-arrests were significantly lower among drug court graduates (13%) than offenders with no program participation (30%). The study results suggest that drug court participation and graduation decrease the likelihood of repeated arrests, including drug-related arrests. Drug courts represent a promising collaboration between criminal justice and public health agencies. [ABSTRACT FROM AUTHOR]

This paper presents an experimental simulation of a summer season marine fog-stratus case along the west coast of California using the US Navy COAMPS(tm) model. The purpose is to show the potential usefulness of mesoscale models in forecasting this type of marine boundary weather phenomenon. The role of data assimilation and the impacts of solar radiation, microphysics, and vertical resolution in improving the forecasts are examined. The model capability in forecasting the burn-off process over the San Francisco Bay area is also tested with very high horizontal resolution (2-km grid size) using the model''s one-way nesting technique. The model demonstrates promising capacity in this case to replicate the temporal and spatial cloud coverage over the San Francisco Bay and surrounding area, shown in satellite imagery, despite a 2-h lag to complete clearing over the bay. This study also suggests that a better microphysics parameterization and proper representation of microphysics in the solar radiation scheme are both important for COAMPS(tm) to produce more realistic simulations and to improve the burn-off forecast. [Copyright &y& Elsevier]

This paper formulates and applies a unified mixed-logit framework for joint analysis of revealed and stated preference data that accommodates a flexible competition pattern across alternatives, scale difference in the revealed and stated choice contexts, heterogeneity across individuals in the intrinsic preferences for alternatives, heterogeneity across individuals in the responsiveness to level-of-service factors, state-dependence of the stated choices on the revealed choice, and heterogeneity across individuals in the state-dependence effect. The estimation of the mixed logit formulation is achieved using simulation techniques that employ quasi-random Monte Carlo draws. The formulation is applied to examine the travel behavior responses of San Francisco Bay Bridge users to changes in travel conditions. The data for the study are drawn from surveys conducted as part of the 1996 San Francisco Bay Area Travel Study. The results of the mixed logit formulation are compared with those of more restrictive structures on the basis of parameter estimates, implied trade-offs among level-of-service attributes, heterogeneity and state-dependence effects, data fit, and substantive implications of congestion pricing policy simulations. [Copyright &y& Elsevier]

This paper describes the behavior of multi-lane freeway traffic, upstream of an oversaturated off-ramp. It is based on empirical evidence from freeway I-880 (northbound) near Oakland, CA. The main findings are:FIFO blockage. Even on wide freeways, an off-ramp queue can grow across all lanes and entrap through vehicles in a first-in-first-out (FIFO) system with similar speeds on all lanes and a well-defined kinematic wave (KW). This can hamper freeway flow much more than an on-ramp bottleneck. (In our case the FIFO regime arose a little over 2 km upstream of the exit and reduced discharge flow approximately to an average of 1500 veh/h per lane across all lanes.)Variable capacity. Under FIFO, the freeway discharge flow can change significantly without a change in the off-ramp flow when the percent of exiting vehicles changes. (In our case, it increased to 5750 veh/h after 30 min at 4520 veh/h when the exit percentage declined from 29% to 24%.)Non-FIFO congested regimes. Multi-pipe traffic states, where queued lanes move at different speeds, can persist for a long time. Presumably, this happens because different drivers prefer different lanes depending on their destination. (In our case, multi-pipe queued regimes were detected immediately upstream and immediately downstream of the FIFO queue.) Semi-congested traffic regimes, where some lanes are queued and others are not, also exist. (They were detected downstream of the FIFO queue.)Regularity of the flow-density scatter-plots. If one excludes the periods of time corresponding to multi-pipe flow and regime transitions, flow-density points across all lanes are quite close to a “fundamental diagram” with two branches. During multi-pipe periods, flow-density scatter points cluster along an inner line, parallel to the congested branch, because drivers give themselves longer spacings when driving under these conditions. [Copyright &y& Elsevier]

Presents abstracts of papers presented at the 63rd Annual Meeting of the Society for Investigative Dermatology, held in May 2002 in Los Angeles, California. Inclusion of angiogenesis and vascular biology; Growth factors and signal transduction; Photobiology; Pigmentation.

This paper presents an empirical application of a congestion–alleviation strategy that C. Daganzo [Transportation Research B 29 (1995) 139–154] proposed as a “hybrid between rationing and pricing”. This strategy is applied to the San Francisco Bay Bridge corridor, in search of a practical and Pareto-improving solution to the Bridge''s congestion. The work relies on a mode-split model for work trips across four different income groups residing in 459 origin zones, and it applies an equilibrium analysis based on Bridge performance. Results indicate that modal utilities (and thus choices) are sensitive to the specific combination of toll and rationing rate, as well as to the Bridge''s travel-time (or performance) function, and the length of the congested section. Though no combination of tolls plus rationing rates was found to benefit all groups of travelers studied, further investigations may improve upon these results by refining some of the assumptions made here. [Copyright &y& Elsevier]