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Previous numerical simulations (TeraShake1) of large (Mw 7:7) southern San Andreas fault earthquakes predicted localized areas of strong amplification in the Los Angeles area associated with directivity and wave-guide effects from northwestward-propagating rupture scenarios. The TeraShake1 source was derived from inversions of the 2002 Mw 7:9 Denali, Alaska, earthquake. That source was relatively smooth in its slip distribution and rupture characteristics, owing both to resolution limits of the inversions and simplifications imposed by the kinematic parameterization. New simulations (TeraShake2), with a more complex source derived from spontaneous rupture modeling with small-scale stress-drop heterogeneity, predict a similar spatial pattern of peak ground velocity (PGV), but with the PGV extremes decreased by factors of 2-3 relative to TeraShake1. The TeraShake2 source excites a less coherent wave field, with reduced along-strike directivity accompanied by streaks of elevated ground motion extending away from the fault trace. The source complexity entails abrupt changes in the direction and speed of rupture correlated to changes in slip-velocity amplitude and waveform, features that might prove challenging to capture in a purely kinematic parameterization. Despite the reduced PGV extremes, northwest-rupturing TeraShake2 simulations still predict entrainment by basin structure of a strong directivity pulse, with PGVs in Los Angeles and San Gabriel basins that are much higher than predicted by empirical methods. Significant areas of those basins have predicted PGV above the 2% probability of exceedance (POE) level relative to current attenuation relationships (even when the latter includes a site term to account for local sediment depth), and wave-guide focusing produces localized areas with PGV at roughly 0.1%-0.2% POE (about a factor of 4.5 above the median). In contrast, at rock sites in the 0-100-km distance range, the median TeraShake2 PGVs are in very close agreement with the median empirical prediction, and extremes nowhere reach the 2% POE level. The rock-site agreement lends credibility to some of our source-modeling assumptions, including overall stress-drop level and the manner in which we assigned dynamic parameters to represent the mechanical weakness of near-surface material. Future efforts should focus on validating and refining these findings, assessing their probabilities of occurrence relative to alternative rupture scenarios for the southern San Andreas fault, and incorporating them into seismic hazard estimation for southern California. [ABSTRACT FROM AUTHOR]

Objective: To determine the percentiles of weight for age in cerebral palsy according to gender and Gross Motor Function Classification System (GMFCS) level and to identify weights associated with negative health outcomes., Patients and Methods: This study consists of a total of 102 163 measurements of weight from 25 545 children with cerebral palsy who were clients of the California Department of Developmental Services from 1988 through 2002. Percentiles were estimated using generalized additive models for location, scale, and shape. Numbers of comorbidities were compared using t tests. The effect of low weight on mortality was estimated with proportional hazards regression., Results: Weight-for-age percentiles in children with cerebral palsy varied with gender and GMFCS level. Comorbidities were more common among those with weights below the 20th percentile in GMFCS levels I through IV and level V without feeding tubes (P < .01). For GMFCS levels I and II, weights below the 5th percentile were associated with a hazard ratio of 2.2 (95% confidence interval: 1.3-3.7). For children in GMFCS levels III through V, weights below the 20th percentile were associated with a mortality hazard ratio of 1.5 (95% confidence interval: 1.4-1.7)., Conclusions: Children with cerebral palsy who have very low weights have more major medical conditions and are at increased risk of death. The weight-for-age charts presented here may assist in the early detection of nutritional issues or other health risks in these children.

Objective: To determine the causes of death of individuals with developmental disabilities that occur more frequently among those with remote symptomatic epilepsy (i.e., epilepsy occurring in persons with developmental delay or identified brain lesions) than for those without., Methods: The authors compared causes of mortality in persons with (n = 10,030) and without (n = 96,163) history of epilepsy in a California population of persons with mild developmental disabilities, 1988 to 2002. Subjects had traumatic brain injury, cerebral palsy, Down syndrome, autism, or a developmental disability with other or unknown etiology. There were 721,759 person-years of data, with 2,397 deaths. Underlying causes of death were determined from the State of California's official mortality records. Cause-specific death rates and standardized mortality ratios (SMRs) were computed for those with and without epilepsy relative to subjects in the California general population. Comparisons were then made between SMRs of those with and without epilepsy, and CIs on the ratios of SMRs were determined., Results: Death rates for persons with epilepsy were elevated for several causes. The greatest excess was due to seizures (International Classification of Diseases-9 [ICD-9] 345; SMR 53.1, 95% CI 28.0 to 101.0) and convulsions (ICD-9 780.3; SMR 25.2, 95% CI 11.7 to 54.2). Other causes occurring more frequently in those with epilepsy included brain cancer (SMR 5.2, 95% CI 2.2 to 12.1), respiratory diseases (SMR 1.7, 95% CI 1.2 to 2.5), circulatory diseases (SMR 1.3, 95% CI 1.0 to 1.7), and accidents (SMR 2.7, 95% CI 1.9 to 3.7), especially accidental drowning (SMR 12.8, 95% CI 7.0 to 23.2)., Conclusions: Remote symptomatic epilepsy is associated with an increased risk of death. Seizures, aspiration pneumonia, and accidental drowning are among the leading contributors.

Background: Published estimates of excess mortality associated with epilepsy vary greatly. How much, if any, of the excess is attributable to the seizures themselves as opposed to an underlying condition causing the epilepsy is not clear from the literature. This article offers evidence that epilepsy per se is associated with excess mortality. The excess varies according to severity and frequency of seizures., Materials and Methods: The authors studied mortality rates of developmentally disabled persons in California with and without epilepsy. In order to focus on the effect on mortality risk of epilepsy per se, they included only persons with good motor function (able to walk and climb stairs) and at worst moderate mental retardation (MR). The data were 506,204 person-years and 1523 deaths among 80,682 California subjects of age 5 to 65 years during the 1988-1999 study period. Mortality rates for persons with epilepsy were compared to rates for persons with no history of epilepsy., Results: Mortality rates were higher for persons with epilepsy than for those without. Excess death rates (EDRs) varied according to type and frequency of seizures. Combined EDRs were 6 (deaths per 1000 person-years) for persons with recent (< 12 months) history of status epilepticus, 5 for recent history of generalized tonic-clonic (GTC) seizures, 3 for recent history of seizures but no recent GTC seizures, and less than 1 for a history of seizures but no recent events., Conclusions: The data presented here are evidence that epilepsy per se is associated with increased mortality. The EDRs reported here may be better measures of excess mortality due to epilepsy than previously published estimates.

Objective: To determine which causes of death are more frequent in persons with traumatic brain injury (TBI), and by how much, compared with the general population. Our focus was the period beginning 1 yr after injury., Design: Subjects were 2320 Californians with long-term mental disability after a TBI at age 10 yr or more, followed up between 1988 and 1997. The units of study were person-years, each linked to the subject's age, gender, level of ambulation, time since injury, and cause of death (if any) for the specific year. Observed numbers of cause-specific deaths were compared with numbers expected according to general population mortality rates., Results: Mortality was higher between 1.0 and 5.0 yr postinjury than after 5.0 yr and was strongly related to reduced mobility. Death rates were elevated for circulatory diseases, respiratory diseases, choking/suffocation, and seizures, with seizure deaths being relatively frequent, even among the most ambulatory., Conclusions: Death rates for several causes are elevated in persons with long-term sequelae of TBI. The increased risk of choking/suffocation should be of interest to caregivers. Life expectancy seems to be reduced, even for patients who are fully ambulatory.