State of California

Current day concentrations of ambient air pollution have been associated with a range of adverse health effects, particularly mortality and morbidity due to cardiovascular and respiratory diseases. In this review, we summarize the evidence from epidemiological studies on long-term exposure to fine and coarse particles, nitrogen dioxide (NO2) and elemental carbon on mortality from all-causes, cardiovascular disease and respiratory disease. We also summarize the findings on potentially susceptible subgroups across studies. We identified studies through a search in the databases Medline and Scopus and previous reviews until January 2013 and performed a meta-analysis if more than five studies were available for the same exposure metric. There is a significant number of new studies on long-term air pollution exposure, covering a wider geographic area, including Asia. These recent studies support associations found in previous cohort studies on PM2.5. The pooled effect estimate expressed as excess risk per 10 μg/m3 increase in PM2.5 exposure was 6% (95% CI 4, 8%) for all-cause and 11% (95% CI 5, 16%) for cardiovascular mortality. Long-term exposure to PM2.5 was more associated with mortality from cardiovascular disease (particularly ischemic heart disease) than from non-malignant respiratory diseases (pooled estimate 3% (95% CI −6, 13%)). Significant heterogeneity in PM2.5 effect estimates was found across studies, likely related to differences in particle composition, infiltration of particles indoors, population characteristics and methodological differences in exposure assessment and confounder control. All-cause mortality was significantly associated with elemental carbon (pooled estimate per 1 μg/m3 6% (95% CI 5, 7%)) and NO2 (pooled estimate per 10 μg/m3 5% (95% CI 3, 8%)), both markers of combustion sources. There was little evidence for an association between long term coarse particulate matter exposure and mortality, possibly due to the small number of studies and limitations in exposure assessment. Across studies, there was little evidence for a stronger association among women compared to men. In subjects with lower education and obese subjects a larger effect estimate for mortality related to fine PM was found, though the evidence for differences related to education has been weakened in more recent studies.

Whether exposure to air pollution adversely affects the growth of lung function during the period of rapid lung development that occurs between the ages of 10 and 18 years is unknown.In this prospective study, we recruited 1759 children (average age, 10 years) from schools in 12 southern California communities and measured lung function annually for eight years. The rate of attrition was approximately 10 percent per year. The communities represented a wide range of ambient exposures to ozone, acid vapor, nitrogen dioxide, and particulate matter. Linear regression was used to examine the relationship of air pollution to the forced expiratory volume in one second (FEV(1)) and other spirometric measures.Over the eight-year period, deficits in the growth of FEV(1) were associated with exposure to nitrogen dioxide (P=0.005), acid vapor (P=0.004), particulate matter with an aerodynamic diameter of less than 2.5 microm (PM(2.5)) (P=0.04), and elemental carbon (P=0.007), even after adjustment for several potential confounders and effect modifiers. Associations were also observed for other spirometric measures. Exposure to pollutants was associated with clinically and statistically significant deficits in the FEV(1) attained at the age of 18 years. For example, the estimated proportion of 18-year-old subjects with a low FEV(1) (defined as a ratio of observed to expected FEV(1) of less than 80 percent) was 4.9 times as great at the highest level of exposure to PM(2.5) as at the lowest level of exposure (7.9 percent vs. 1.6 percent, P=0.002).The results of this study indicate that current levels of air pollution have chronic, adverse effects on lung development in children from the age of 10 to 18 years, leading to clinically significant deficits in attained FEV(1) as children reach adulthood.

The prevalence of "toxic stress"and huge downstream consequences in disease, suffering, and financial costs make prevention and early intervention crucial, say Charles A Nelson and colleagues

In this paper the solution to the problem of placing n connected points (or nodes) in r-dimensional Euclidean space is given. The criterion for optimality is minimizing a weighted sum of squared distances between the points subject to quadratic constraints of the form X′X = 1, for each of the r unknown coordinate vectors. It is proved that the problem reduces to the minimization of a sum or r positive semi-definite quadratic forms which, under the quadratic constraints, reduces to the problem of finding r eigenvectors of a special “disconnection” matrix. It is shown, by example, how this can serve as a basis for cluster identification.

BACKGROUND: The purpose of this review was to identify critical data and research needs in addressing the following question: What are the primary factors that affect the time lost from work, return-to-work (RTW), subsequent unemployment, and changes in occupation after disabling illness or injury? METHODS: Review of the literature to identify research challenges originating from the multitude of disciplines, data sources, outcome measures, and methodological and analytical problems. RESULTS: About 100 different determinants of RTW outcomes were identified. Their impact varies across different phases of the disablement process. Recommendations are provided for addressing five selected research challenges. CONCLUSION: Interdisciplinary research needs to develop a comprehensive conceptual framework. Priority should be given to studies on specific domains of risk factors meeting five selection criteria: amenability to change; relevance to users of research; generalizability across health conditions, disability phases, and settings; "degree of promise" as derived from qualitative exploratory studies; and capacity to improve measurement instruments. Combining qualitative and quantitative research methods is necessary to bridge existing knowledge gaps.

Exposures to ambient air pollutants have been associated with adverse birth outcomes. We investigated the effects of air pollutants on birth weight mediated by reduced fetal growth among term infants who were born in California during 1975-1987 and who participated in the Children's Health Study. Birth certificates provided maternal reproductive history and residence location at birth. Sociodemographic factors and maternal smoking during pregnancy were collected by questionnaire. Monthly average air pollutant levels were interpolated from monitors to the ZIP code of maternal residence at childbirth. Results from linear mixed-effects regression models showed that a 12-ppb increase in 24-hr ozone averaged over the entire pregnancy was associated with 47.2 g lower birth weight [95% confidence interval (CI), 27.4-67.0 g], and this association was most robust for exposures during the second and third trimesters. A 1.4-ppm difference in first-trimester carbon monoxide exposure was associated with 21.7 g lower birth weight (95% CI, 1.1-42.3 g) and 20% increased risk of intrauterine growth retardation (95% CI, 1.0-1.4). First-trimester CO and third-trimester O3 exposures were associated with 20% increased risk of intrauterine growth retardation. A 20-microg/m3 difference in levels of particulate matter < or = 10 microm in aerodynamic diameter (PM10) during the third trimester was associated with a 21.7-g lower birth weight (95% CI, 1.1-42.2 g), but this association was reduced and not significant after adjusting for O3. In summary, O3 exposure during the second and third trimesters and CO exposure during the first trimester were associated with reduced birth weight.

BACKGROUND: Job characteristics may constitute a barrier to return-to-work (RTW) after compensated disabling low back pain (LBP). This study examines the impact of psychosocial job factors on time to RTW separately during the acute and subacute/chronic disability phases. METHODS: This is a retrospective cohort study of 433 LBP workers' compensation claimants with 1-4 years of follow-up. The association of psychosocial job factors with duration of work disability was estimated with Cox regression models, adjusting for injury history and severity, physical workload, and demographic and employment factors. RESULTS: High physical and psychological job demands and low supervisory support are each associated with about 20% lower RTW rates during all disability phases. High job control, especially control over work and rest periods, is associated with over 30% higher RTW rates, but only during the subacute/chronic disability phase starting 30 days after injury. Job satisfaction and coworker support are unrelated to time to RTW. CONCLUSIONS: Duration of work disability is associated with psychosocial job factors independent of injury severity and physical workload. The impact of these risk factors changes significantly over the course of disability.

DNAs of type strains and representative members of Actinomyces groups from the human periodontal flora and from other habitats were compared by using the S1 nuclease procedure to determine their genetic relatedness. One rather common group from the human periodontal flora, previously called "Actinomyces D08," is phenotypically distinct from, and genetically unrelated to, previously described species. We propose the name of Actinomyces georgiae for this organism; the type strain is strain ATCC 49285. Another common group from the human periodontal flora is Actinomyces israelii serotype II, which was found genetically distinct from the type strain of A. israelii (serotype I) and from other previously described species of Actinomyces. We propose the name Actinomyces gerencseriae for this organism; the type strain is strain ATCC 23860. A. naeslundii serotype I strains were distinct from the other strains studied. A separate genospecies which included strains of A. naeslundii serotypes II and III and A. viscosus serotype II was delineated. Strains of Actinomyces serotype WVA 963 constitute an additional distinct genospecies. Because there are no reliable phenotypic tests, other than serological analyses, to differentiate Actinomyces serotype WVA 963 and the two genospecies of A. naeslundii, no taxonomic changes are proposed for these three genospecies.

Abstract. To identify major sources of ambient fine particulate matter (PM2.5, dp &lt; 2.5 μm) and quantify their contributions in the state of California, a positive matrix factorization (PMF) receptor model was applied on Speciation Trends Network (STN) data, collected between 2002 and 2007 at eight distinct sampling locations, including El Cajon, Rubidoux, Los Angeles, Simi Valley, Bakersfield, Fresno, San Jose, and Sacramento. Between five to nine sources of fine PM were identified at each sampling site, several of which were common among multiple locations. Secondary aerosols, including secondary ammonium nitrate and ammonium sulfate, were the most abundant contributor to ambient PM2.5 mass at all sampling sites, except for San Jose, with an annual average cumulative contribution of 26 to 63%, across the state. On an annual average basis, vehicular emissions (including both diesel and gasoline vehicles) were the largest primary source of fine PM at all sampling sites in southern California (17–18% of total mass), whereas in Fresno and San Jose, biomass burning was the most dominant primary contributor to ambient PM2.5 (27 and 35% of total mass, respectively), in general agreement with the results of previous source apportionment studies in California. In Bakersfield and Sacramento, vehicular emissions and biomass burning displayed relatively equal annual contributions to ambient PM2.5 mass (12 and 25%, respectively). Other commonly identified sources at all sites included aged and fresh sea salt and soil, which contributed to 0.5–13%, 2–27%, and 1–19% of the total mass, respectively, across all sites and seasons. In addition, a few minor sources were identified exclusively at some of the sites (e.g., chlorine sources, sulfate-bearing road dust, and different types of industrial emissions). These sources overall accounted for a small fraction of the total PM mass across the sampling locations (1 to 15%, on an annual average basis).

Since about 1950 there has been a trend in the California Sierra Nevada toward a decreasing portion of the total annual streamflow occurring during April through July, while the streamflow during autumn and winter has increase. This trend not only has important ramifications with regard to water management, it also brings up the question of whether this represents a shift toward earlier release of the snowpack resulting from greenhouse warming. Therefore, the observed record has been examined in terms of relative influences of temperature and precipitation anomalies on the timing of streamflow in this region. To carry out this study, the fraction of annual streamflow (called the fractional streamflow) occurring in November-January (NDJ), February-April (FMA), and May-July (MJJ) at low, medium, and high elevation basins in California and 0regon was examined. Linear regression models were used to relate precipitation and temperature to the fractional streamflow at the three elevations for each season. Composites of monthly temperature and precipitation were employed to further examine the fractional streanflow in its high and low tercile extremes. Long time series of climatic and hydrologic data were also looked at to infer the causes in the trend toward earlier runoff. For the low-elevation basins, there is a dominant influence of precipitation on seasonal fractional streamflow. Middle-elevation basins exhibit a longer memory of precipitation and temperature in relation to their fractional stream-flow. In-season precipitation is still the most important influence upon NDJ and FMA fractional streamflow; however, the influence of temperature in melting the snowpack is seen on MJJ fractional streamflow, whose strongest influence is FMA temperature. At higher elevation prior-season precipitation exerts a greater influence than at low and middle elevations, and seasonal temperature anomalies have an effect on all seasonal streamflow fractions. There are several causes for the trend toward decreasing fractional streamflow in the spring and summer. Concomitant with the trend in the timing of streamflow was an increase in NDJ (most notably November) precipitation. There also has been a trend toward higher spring temperatures over most of the western United States, but since them has also been a trend toward decreasing temperatures in the southeast, we do not interpret this as a signal of anthropogenic warming. Other factors in the trend toward earlier streamflow may include a decrease in MJJ precipitation and an increase in August–October precipitation.

Pontis provides a systematic methodology for allocating funds, evaluating current and future needs of bridges and options to meet those needs, and recommending the optimal policy for each bridge in the context of overall network benefits, budgets, and restrictions. After a trial implementation in California and extensive testing in several states, the system was adopted by AASHTO (Association of American State Highway Officials). Currently, over 40 states are implementing Pontis. At the heart of Pontis is a set of predictive and optimization models which derive their information from judgmental, engineering, and economic models and various databases. The predictive models start with engineering-based subjective inputs and update themselves in a Bayesian context as data is collected. The optimization models consist of interrelated Markov decision models and mathematical programming tools and models.

INTRODUCTION: Autosomal-dominant Alzheimer's disease (ADAD) represents a crucial population for identifying prevention strategies that might modify disease course for cognitively unimpaired individuals at high imminent risk for developing symptoms due to Alzheimer's disease (AD), that is, who have "preclinical" AD. Crenezumab is an antiamyloid monoclonal antibody that binds monomeric and aggregated forms of amyloid β, with highest affinity for oligomers; it is in development for early stages of sporadic AD and for ADAD. METHODS: E280A mutation carriers from family kindreds with ADAD in Colombia. Participants were randomized to receive either crenezumab or placebo for 260 weeks. The study was designed to enroll a planned total of 300 participants, including 200 preclinical mutation carriers (approximately 100 treatment, 100 placebo) and an additional control group of mutation noncarriers from the same family kindreds included to mask mutation carrier status (100 placebo only). The primary outcome is change in the Alzheimer's Prevention Initiative ADAD Composite Cognitive Test Score from baseline to week 260. Secondary outcomes include time to progression to mild cognitive impairment due to AD or dementia due to AD; changes in dementia severity, memory, and overall neurocognitive functioning; and changes in amyloid-positron emission tomography, fluorodeoxyglucose-positron emission tomography, magnetic resonance imaging volumes, and cerebrospinal fluid levels of β amyloid, tau, and p-tau. Safety and tolerability are assessed. RESULTS: Two hundred fifty-two participants were enrolled between December 2013 and February 2017. DISCUSSION: We describe the first large-scale, potentially label-enabling clinical trial of a preclinical treatment for ADAD. Results from this trial will inform on the efficacy of crenezumab for delaying onset of, slowing decline in, or preventing cognitive impairment in individuals with preclinical ADAD and will foster an improved understanding of AD biomarkers and their relationship to clinical outcomes.

An accurate and timely crop-type map is essential in water planning in California. So far, no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. We have explored the potential of Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance images to annually map major crop types in the San Joaquin Valley, California. A phenology-based classification approach has been employed, which has extracted phenological metrics from normalized difference vegetation index (NDVI) profiles and identified crop types based on these metrics using decision trees. According to a comparison with traditional maximum-likelihood classification, this phenology-based approach has shown great advantages when the size of the training set was limited by ground-truth availability and when the central tendency was absent in agricultural systems heavily influenced by human activities.

OBJECTIVE: Virus infections are the most common causes of encephalitis, a syndrome characterized by acute inflammation of the brain. More than 150 different viruses have been implicated in the pathogenesis of encephalitis; however, because of limitations with diagnostic testing, causative factors of more than half of the cases remain unknown. METHODS: To investigate whether human herpesvirus-6 (HHV-6) is a causative agent of encephalitis, we examined for evidence of virus infection by determining the presence of viral sequence using polymerase chain reaction and assessed HHV-6 antibody reactivity in the cerebrospinal fluid of encephalitis patients with unknown cause. In a cohort study, we compared virus-specific antibody levels in cerebrospinal fluid samples of patients with encephalitis, relapsing-remitting multiple sclerosis, and other neurological diseases. RESULTS: Our results demonstrated increased levels of HHV-6 IgG, as well as IgM levels, in a subset of encephalitis patients compared with other neurological diseases. Moreover, cell-free viral DNA that is indicative of active infection was detected in 40% (14/35) of encephalitis patients, whereas no amplifiable viral sequence was found in either relapsing-remitting MS or other neurological diseases patients. In addition, a significant correlation between polymerase chain reaction detection and anti-HHV-6 antibody response was also demonstrated. INTERPRETATION: Collectively, these results suggested HHV-6 as a possible pathogen in a subset of encephalitis cases.

Relatively few studies have examined recoveries from source waters by using Environmental Protection Agency method 1623 with organism spike doses that are environmentally realistic and at turbidity levels commonly found in surface waters. In this study, we evaluated the filtration capacities and recovery efficiencies of the Gelman Envirochek (standard filter) and the Gelman Envirochek high-volume (HV) sampling capsules under environmental conditions. We also examined the performance of method 1623 under ambient conditions with matrix spike experiments using 10 organisms/liter. Under turbid conditions, the HV capsule filtered approximately twice the volume filtered by the standard filter, but neither could filter 10 liters without clogging. In low-turbidity waters, oocyst, but not cyst, recoveries were significantly higher when the HV capsule was used. In turbid waters, organism recoveries were lower than those in nonturbid waters and were not significantly different for the different filters. When the HV capsule was used, Cryptosporidium recoveries ranged from 36 to 75%, and Giardia recoveries ranged from 0.5 to 53%. For both organisms, recoveries varied significantly by site. Turbidity could explain variation in Giardia recoveries (r(2) = 0.80) but not variation in Cryptosporidium recoveries (r(2) = 0.16). The inconsistent recoveries across sites suggested that the background matrix of the ambient water affected recovery by method 1623. A control sample collected at the height of the winter rainy season detected one organism, highlighting the difficulty of using this method to accurately measure pathogen abundance under natural conditions. Our findings support the use of the HV filter under field conditions but suggest that designing a cost-effective and statistically valid monitoring program to evaluate sources and loads of protozoan pathogens may be difficult.

BACKGROUND: Studies of low back pain (LBP) disability remain largely incomparable because of different outcome definitions. To date, systematic comparisons of alternative outcome measures have not been made. METHODS: Duration of work disability was studied in a 3-year cohort of 850 workers' compensation LBP claimants. Eleven administrative outcome measures were compared using Kaplan-Meier estimates of the proportion of claimants still on disability benefits during 3.5 years of follow-up. RESULTS: The estimated mean duration of work disability was 75 days for the first temporary disability (TD) episode, 108 days for cumulative time on TD, and 337 for total compensated days, which includes all types of wage replacement benefits during vocational rehabilitation, temporary and permanent disability. CONCLUSIONS: Commonly used administrative measures of lost workdays--time to first return to work and time on temporary disability--substantially underestimate the duration of work disability compared to measures based on all wage replacement benefits.

The etiology of sporadic amyotrophic lateral sclerosis (ALS), the most common form of this degenerative disease of the motor neurons, is still unknown, despite extensive investigation of several genetic and environmental potential risk factors. We have reviewed laboratory and epidemiological studies assessing the role of exposure to neurotoxic chemicals (metalloid selenium; heavy metals mercury, cadmium, and lead; pesticides) in ALS etiology by summarizing the results of these investigations and examining their strengths and limitations. Despite limitations in the exposure assessment methodologies typically used in human studies, we found suggestive epidemiological evidence and biologic plausibility for an association between ALS and antecedent overexposure to environmental selenium and pesticides. The relation with mercury, cadmium, and lead appears weaker.

BACKGROUND: Workers' compensation wage replacement data have recently been used to estimate time to return to work (RTW) and the number of work days lost after occupational injury. The degree to which indemnity-based measures reflect self-reported work disability has until now not been studied. METHOD: Kaplan-Meier curves of administrative and self-reported measures of duration of work disability were compared within a sample of 433 low back injury claimants followed up for 1 to 3.7 years. RESULTS: Administrative measures consistently and significantly underestimated the duration of disability when compared to self-reported measures of RTW. The difference between the estimated mean number of work days lost for comparable administrative and self-reported measures ranged from 142 to 334 days. CONCLUSIONS: Number of work days lost after low back injury is substantially underestimated by measures based on the duration of wage replacement benefits. This calls into question the adequacy of indemnity benefits and underscores the need for disability prevention programs.

Multipotent trophoblasts undergo dynamic morphological movement and cellular differentiation after conceptus implantation to generate placenta. However, the mechanism controlling trophoblast development and differentiation during peri-implantation development in human remains elusive. In this study, we modeled human conceptus peri-implantation development from blastocyst to early postimplantation stages by using an in vitro coculture system and profiled the transcriptome of 476 individual trophoblast cells from these conceptuses. We revealed the genetic networks regulating peri-implantation trophoblast development. While determining when trophoblast differentiation happens, our bioinformatic analysis identified T-box transcription factor 3 (TBX3) as a key regulator for the differentiation of cytotrophoblast (CT) into syncytiotrophoblast (ST). The function of TBX3 in trophoblast differentiation is then validated by a loss-of-function experiment. In conclusion, our results provided a valuable resource to study the regulation of trophoblasts development and differentiation during human peri-implantation development.

Abstract Changes in land use and land cover (LULC) have important and fundamental interactions with the global climate system. Top‐down global scale projections of land use change have been an important component of climate change research; however, their utility at local to regional scales is often limited. The goal of this study was to develop an approach for projecting changes in LULC based on land use histories and demographic trends. We developed a set of stochastic, empirical‐based projections of LULC change for the state of California, for the period 2001–2100. Land use histories and demographic trends were used to project a “business‐as‐usual” (BAU) scenario and three population growth scenarios. For the BAU scenario, we projected developed lands would more than double by 2100. When combined with cultivated areas, we projected a 28% increase in anthropogenic land use by 2100. As a result, natural lands were projected to decline at a rate of 139 km 2 yr −1 ; grasslands experienced the largest net decline, followed by shrublands and forests. The amount of cultivated land was projected to decline by approximately 10%; however, the relatively modest change masked large shifts between annual and perennial crop types. Under the three population scenarios, developed lands were projected to increase 40–90% by 2100. Our results suggest that when compared to the BAU projection, scenarios based on demographic trends may underestimate future changes in LULC. Furthermore, regardless of scenario, the spatial pattern of LULC change was likely to have the greatest negative impacts on rangeland ecosystems.