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This study presents a quantitative and geospatial description of global losses due to earthquake-induced secondary effects, including landslide, liquefaction, tsunami, and fire for events during the past 40 years. These processes are of great importance to the US Geological Survey's (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system, which is currently being developed to deliver rapid earthquake impact and loss assessments following large/significant global earthquakes. An important question is how dominant are losses due to secondary effects (and under what conditions, and in which regions)? Thus, which of these effects should receive higher priority research efforts in order to enhance PAGER's overall assessment of earthquakes losses and alerting for the likelihood of secondary impacts? We find that while 21.5% of fatal earthquakes have deaths due to secondary (non-shaking) causes, only rarely are secondary effects the main cause of fatalities. The recent 2004 Great Sumatra-Andaman Islands earthquake is a notable exception, with extraordinary losses due to tsunami. The potential for secondary hazards varies greatly, and systematically, due to regional geologic and geomorphic conditions. Based on our findings, we have built country-specific disclaimers for PAGER that address potential for each hazard (Earle et al., Proceedings of the 14th World Conference of the Earthquake Engineering, Beijing, China, 2008). We will now focus on ways to model casualties from secondary effects based on their relative importance as well as their general predictability.

OBJECTIVES: To evaluate the risk of cancer and other diseases among workers engaged in aircraft manufacturing and potentially exposed to compounds containing chromate, trichloroethylene (TCE), perchloroethylene (PCE), and mixed solvents. METHODS: A retrospective cohort mortality study was conducted of workers employed for at least 1 year at a large aircraft manufacturing facility in California on or after 1 January 1960. The mortality experience of these workers was determined by examination of national, state, and company records to the end of 1996. Standardised mortality ratios (SMRs) were evaluated comparing the observed numbers of deaths among workers with those expected in the general population adjusting for age, sex, race, and calendar year. The SMRs for 40 cause of death categories were computed for the total cohort and for subgroups defined by sex, race, position in the factory, work duration, year of first employment, latency, and broad occupational groups. Factory job titles were classified as to likely use of chemicals, and internal Poisson regression analyses were used to compute mortality risk ratios for categories of years of exposure to chromate, TCE, PCE, and mixed solvents, with unexposed factory workers serving as referents. RESULTS: The study cohort comprised 77,965 workers who accrued nearly 1.9 million person-years of follow up (mean 24.2 years). Mortality follow up, estimated as 99% complete, showed that 20,236 workers had died by 31 December 1996, with cause of death obtained for 98%. Workers experienced low overall mortality (all causes of death SMR 0.83) and low cancer mortality (SMR 0.90). No significant increases in risk were found for any of the 40 specific cause of death categories, whereas for several causes the numbers of deaths were significantly below expectation. Analyses by occupational group and specific job titles showed no remarkable mortality patterns. Factory workers estimated to have been routinely exposed to chromate were not at increased risk of total cancer (SMR 0.93) or of lung cancer (SMR 1.02). Workers routinely exposed to TCE, PCE, or a mixture of solvents also were not at increased risk of total cancer (SMRs 0.86, 1.07, and 0.89, respectively), and the numbers of deaths for specific cancer sites were close to expected values. Slight to moderately increased rates of non-Hodgkin's lymphoma were found among workers exposed to TCE or PCE, but none was significant. A significant increase in testicular cancer was found among those with exposure to mixed solvents, but the excess was based on only six deaths and could not be linked to any particular solvent or job activity. Internal cohort analyses showed no significant trends of increased risk for any cancer with increasing years of exposure to chromate or solvents. CONCLUSIONS: The results from this large scale cohort study of workers followed up for over 3 decades provide no clear evidence that occupational exposures at the aircraft manufacturing factory resulted in increases in the risk of death from cancer or other diseases. Our findings support previous studies of aircraft workers in which cancer risks were generally at or below expected levels.

Two simple efficient techniques to optimise the closed-loop transient response of three-stage amplifiers for large capacitive load applications are proposed and developed. The proposed approaches exploit a current comparator in the inner amplifier nodes to sense the input voltage transients and to switch on an auxiliary driving device providing slew-rate enhancement and settling time improvement without extra static power dissipation. SPECTRE simulations are carried out on a three-stage amplifier adopting a recently proposed reversed-nested Miller compensation strategy with a voltage follower and two nulling resistors, for which a novel design methodology is provided as well. Simulation results confirm the effectiveness of the two proposed techniques, showing a symmetrical step response with a significant improvement in large-signal speed performance. Both proposed solutions are suitable for any particular three-stage amplifier topology and are also independent of the adopted compensation network.

During recent years, aircraft manufacturers focused on environmentally friendly and aerodynamically efficient aircraft concepts that could allow a radical reduction of emissions. The use of a hybrid-electric powertrain is one of the most effective ways to design near-zero-emission aircraft. These aircraft are highly performing and sophisticated so the design process must be extremely accurate. Among the various innovative aspects, the use of distributed engines to improve aerodynamic performance poses new challenges from a structural perspective due to the tip-mounted propeller demanding a complicated design due to reduced flutter performance. This results in higher stiffness requirements and consequently increased mass. Both the weight penalty needed to prevent dynamic instability, and the wing aeroelastic tailoring, crucial to minimize such an additional weight, is of utmost importance. Because of setting up a preliminary approach to estimate the static and dynamic effects of such a non-conventional wing architecture, the present paper shows a comprehensive structural analysis of a wing opportunely designed according to certification specification and equipped with a variable position powertrain. Several different engines are then moved along the wingspan to estimate how it affects the dynamic response using a simplified beam-stick finite element model. The results show that the engine position strongly affects the flutter velocity with a particular band bell curve over the wingspan with the maximum in between 60-70% wingspan. In addition, it is worth noting how the tip propeller may cause a reduction of flutter velocity with respect to the conventional configuration with the turbine mounted in between 30-40% wing-span.

We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical earthquakes (1973–2007). The common purpose of the Atlas and exposure catalog is to calibrate earthquake loss models to be used in the US Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained—to varying degrees—by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to earthquakes, and; (2) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Moreover, earthquake mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this “composite ShakeMap” with existing global hazard models, calculating the spatial area of the existing hazard maps exceeded by the combined ShakeMap ground motions. In general, these analyses suggest that existing global, and regional, hazard maps tend to overestimate hazard. Both the Atlas of ShakeMaps and EXPO-CAT have many potential uses for examining earthquake risk and epidemiology. All of the datasets discussed herein are available for download on the PAGER Web page ( http://earthquake.usgs.gov/eqcenter/pager/prodandref/ ).

The aim of this study was to investigate the relationship between 2-deoxy-2[(18)F]fluoro-D-glucose ([(18)F]FDG) positron emission tomography (PET) and diffusion-weighted magnetic resonance imaging (DWI) with apparent diffusion coefficients (ADC) in brain tumors. Fifteen patients with 18 metastatic brain lesions underwent gadolinium-enhanced fast spoiled gradient echo (Gd-FSPGR), DWI with ADC maps, and [(18)F]FDG PET. Spherical three-dimensional tumor and contralateral control regions of interest (ROIs) were drawn on Gd-FSPGR, ADC and PET images, Gd-FSPGR being the target for statistical parametric mapping with realigned ADC and PET to calculate ROI ratios; linear regression analysis was performed. An inverse correlation (r(2)=0.2746, P=0.0256) was found between PET and ADC ratios; plotting ratios: when PET ratios were high, ADC ratios were low, while, when ADC ratios were high, PET ratios were low. Our preliminary data suggest an inverse relationship between PET and ADC indices. Hypercellular areas could increase impedance to water diffusion, resulting in low ADC values and high [(18)F]FDG uptake, while lower cellularity areas show increased ADC with decreased [(18)F]FDG uptake.

A retrospective cohort study of 14,457 workers at an aircraft maintenance facility was undertaken to evaluate mortality associated with exposures in their workplace. The purpose was to determine whether working with solvents, particularly trichloroethylene, posed any excess risk of mortality. The study group consisted of all civilian employees who worked for at least one year at Hill Air Force Base, Utah, between 1 January 1952 and 31 December 1956. Work histories were obtained from records at the National Personnel Records Centre, St. Louis, Missouri, and the cohort was followed up for ascertainment of vital state until 31 December 1982. Observed deaths among white people were compared with the expected number of deaths, based on the Utah white population, and adjusted for age, sex, and calendar period. Significant deficits occurred for mortality from all causes (SMR 92, 95% confidence interval (95% CI) 90-95), all malignant neoplasms (SMR 90, 95% CI 83-97), ischaemic heart disease (SMR 93, 95% CI 88-98), non-malignant respiratory disease (SMR 87, 95% CI 76-98), and accidents (SMR 61, 95% CI 52-70). Mortality was raised for multiple myeloma (MM) in white women (SMR 236, 95% CI 87-514), non-Hodgkin's lymphoma (NHL) in white women (SMR 212, 95% CI 102-390), and cancer of the biliary passages and liver in white men dying after 1980 (SMR 358, 95% CI 116-836). Detailed analysis of the 6929 employees occupationally exposed to trichloroethylene, the most widely used solvent at the base during the 1950s and 1960s, did not show any significant or persuasive association between several measures of exposure to trichloroethylene and any excess of cancer. Women employed in departments in which fabric cleaning and parachute repair operations were performed had more deaths than expected from MM and NHL. The inconsistent mortality patterns by sex, multiple and overlapping exposures, and small numbers made it difficult to ascribe these excesses to any particular substance. Hypothesis generating results are presented by a variety of exposures for causes of death not showing excesses in the overall cohort.

Although titanium dioxide (TiO₂) is generally regarded as a nontoxic mild pulmonary irritant, some laboratory studies have reported lung adenomas in rats exposed to high levels of TiO₂. Limited data on health effects among humans exist. A retrospective cohort mortality study was conducted among 4241 TiO₂ workers who were employed for at least 6 months, on or after January 1, I960, at four TiO₂ plants in the United States. Exposure categories, defined by plant, job title, and calendar years in the job, were created to examine mortality patterns in those jobs where the potential for TiO₂ exposure is greatest. Standardized mortality ratios (SMRs) and their 95 % confidence intervals (CI) were calculated to compare the mortality pattern of the workers with the general background population. Relative nsks were estimated and trend tests were conducted to examine risk of disease among different exposure level groups in internal analyses. Workers experienced a significantly low overall mortality (SMR = 0.8; 95% CI = 0.8-0.9). No significantly increased SMRs were found for any specific cause of death. Deaths from lung cancer were as expected, and SMRs for this cancer did not increase with increasing TiO₂ levels. Workers in jobs with greatest TiO₂ exposure had significantly fewer than expected total deaths (SMR = 0.7; 95% CI= 0.6- 0.9). Internal analyses revealed no significant trends or exposure-risk associations for total cancers, lung cancer, or other causes of death. Results from our study indicate that the exposures at these United States plants are not associated with increases in the nsk of death from cancer or other diseases. Moreover, workers with likely higher levels of TiO₂ exposure had similar mortality patterns to those with less exposure, as internal analyses among workers revealed no increase in mortality by level of TiO₂ exposure.

Background Known areas of Alzheimer’s pathology, including the hippocampus, entorhinal cortex and medial temporal cortex, have been well‐demonstrated as demonstrating atrophy in Alzheimer’s disease (AD). Using surface‐based morphometry measures, recent studies have suggested that the insula may play a role in memory function. Differences in patients based on amyloid biomarkers are increasingly being studied, particularly comparing individuals who were clinically diagnosed as AD but have negative amyloid biomarkers with those who are positive for amyloid. Atrophy may be similar in the entorhinal cortex between individuals who are amyloid positive versus amyloid negative, despite differences in memory. Here, we aimed to investigate the role of the insula in memory in a cohort of patients (aMCI and dementia) who were positive for amyloid with those who were negative for amyloid. Method We retrospectively analyzed clinical data from 161 aMCI and dementia patients (A+ = 106, A‐ = 55) and 41 healthy participants. Participants completed MRI and cognitive measures. Analysis of cortical thickness and gyrification index of the AD signature areas and the insula were completed using CAT12 and the DKT40 atlas. Memory performance was assessed using the California Verbal Learning Test short form, with long‐delay‐free recall as the variable of interest. Pearson’s correlations and stepwise linear regression were run using signature areas' significant correlations and interactions (adjusted p<0.001). Result Significant correlations with memory performance included insula gyrification and entorhinal and inferior parietal thickness (r=.25, r=.23, and r=.22, respectively). The interaction of insula gyrification with entorhinal thickness demonstrated significant results in predicting memory performance, accounting for 11% variance, even controlling for age. The interaction of reduced entorhinal cortex thickness and increased insula gyrification best explains delayed recall. Conclusion In our well‐characterized clinical cohort of aMCI and dementia with positive and negative amyloid biomarkers, insula gyrification interaction with entorhinal thickness best predicted memory performance measured by CVLT long delay. This finding suggests that, regardless of amyloid status, reduced entorhinal cortex thickness and increased insula atrophy (measured by gyrification, not thickness), impact delayed memory. Studies are necessary to understand the insula's function in memory as well as gyrification and thickness variations across brain regions and their role in cognition.

Background The existing literature has established that Alzheimer's disease (AD) is typically characterized by changes in memory‐associated temporal and parietal lobe atrophy and hypometabolism. However, some individuals clinically diagnosed with AD do not have biomarkers consistent with AD pathology. In this cross‐sectional study, we aimed to investigate differences in memory consolidation, temporal and parietal lobe atrophy, as well as temporal and parietal lobe metabolism within a clinically diagnosed cohort of individuals with amnestic Mild Cognitive Impairment (aMCI) who were either positive or negative for amyloid. Method We retrospectively analyzed clinical data from 149 participants: 78 aMCI amyloid positive (A+), 48 aMCI amyloid negative (A‐), and 41 healthy subjects (HP). To analyze memory performance, we used the CVLT 1. % retained (CVLT%), 2. discrimination (CVLT‐D), 3. false positive (CVLT‐FP), and 4. intrusions errors (CVLT‐I). Entorhinal, supramarginal and angular cortical thickness were computed using CAT 12 and DKT atlas, and hippocampus volume using SLANT. A subset of the aMCI participants had an FDG‐PET, and we extracted the metabolism in the brain regions of interest for analysis. ANOVAs explored differences between groups on memory, brain atrophy, and metabolism (adjusted p<.002). Pearson’s correlations examined relationships between CVLT, MRI values, FDG‐PET measures, and biomarker data (adjusted p<0.0009). Result A+ exhibited worse performance on CVLT%, CVLT‐D, and CVLT‐FP compared to A‐ and HP, and A‐ was worse on those tests compared to HP. There were no significant differences in the hippocampal volume or entorhinal thickness between biomarker status; A+ showed more atrophy in supramarginal and angular thickness than A‐ and HP. A+ showed hypometabolism in the entorhinal cortex compared to A‐. While hippocampus volume was related to CVLT%, CVLT‐D and CVLT‐FP, CVLT% was positively related to all the metabolism in all areas analyzed except hippocampus. Conclusion In our memory clinic cohort characterized by biomarker status, our findings indicated that factors beyond AD might contribute to memory consolidation, temporal lobe atrophy, and temporal lobe. In addition, by inference, adding parietal atrophy to mesial temporal atrophy worsens memory consolidation.