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HiResFlood-UCI was developed by coupling the NWS's hydrologic model (HL-RDHM) with the hydraulic model (BreZo) for flash flood modeling at decameter resolutions. The coupled model uses HL-RDHM as a rainfall-runoff generator and replaces the routing scheme of HL-RDHM with the 2D hydraulic model (BreZo) in order to predict localized flood depths and velocities. A semi-automated technique of unstructured mesh generation was developed to cluster an adequate density of computational cells along river channels such that numerical errors are negligible compared with other sources of error, while ensuring that computational costs of the hydraulic model are kept to a bare minimum. HiResFlood-UCI was implemented for a watershed (ELDO2) in the DMIP2 experiment domain in Oklahoma. Using synthetic precipitation input, the model was tested for various components including HL-RDHM parameters (a priori versus calibrated), channel and floodplain Manning n values, DEM resolution (10 m versus 30 m) and computation mesh resolution (10 m+ versus 30 m+). Simulations with calibrated versus a priori parameters of HL-RDHM show that HiResFlood-UCI produces reasonable results with the a priori parameters from NWS. Sensitivities to hydraulic model resistance parameters, mesh resolution and DEM resolution are also identified, pointing to the importance of model calibration and validation for accurate prediction of localized flood intensities. HiResFlood-UCI performance was examined using 6 measured precipitation events as model input for model calibration and validation of the streamflow at the outlet. The Nash–Sutcliffe Efficiency (NSE) obtained ranges from 0.588 to 0.905. The model was also validated for the flooded map using USGS observed water level at an interior point. The predicted flood stage error is 0.82 m or less, based on a comparison to measured stage. Validation of stage and discharge predictions builds confidence in model predictions of flood extent and localized velocities, which are fundamental to reliable flash flood warning.

The communication of information about natural hazard risks to the public is a difficult task for decision makers. Research suggests that newer forms of technology present useful options for building disaster resilience. However, how effectively these newer forms of media can be used to inform populations of the potential hazard risks in their community remains unclear. This research uses primary data from an in-person survey of 164 residents of Newport Beach, California during the spring of 2014 to ascertain the current and preferred mechanisms through which individuals receive information on flood risks in their community. Factor analysis of survey data identified two predominant routes of dissemination for risk information: older traditional media and newer social media sources. A logistic regression model was specified to identify predictors for choosing a particular communication route. This analysis revealed that age is the central factor in predicting the sources people use to receive risk information. We follow the analysis by discussing this finding and its policy implications.

For equivariant stable homotopy theory, equivariant KK–theory and equivariant derived categories, we show how restriction to a subgroup of finite index yields a finite commutative separable extension, analogous to finite étale extensions in algebraic geometry.

Engineered floodways are floodplains managed by hydraulic controls that can be activated passively, whereby the floodway fills and empties with changes in channel stage, or through a rapid control action, such as the detonation of a levee. During May of 2011, the Birds Point-New Madrid Floodway (NMF) was activated through levee detonation and the performance of this approach is examined herein. A two-dimensional hydraulic flood model (LISFLOOD-FP) is applied to the NMF and calibrated for April and May of 2011 in order to recreate the levee detonation scenario (detonation control). Additionally, the model is applied to simulate flood impacts had the NMF been activated passively, without the deliberate breaching of the levees (passive control). Results show that detonation control reduced flood stages upstream of the activation site by 0.8 m (2.62 ft) without significantly altering overall flooding extent compared with the passive control scenario. Damage estimates from the US Federal Emergency Management Agency HAZUS-MH model indicate that detonation control slightly reduced losses associated with building replacement costs and damaged crops (4.0 % reduction). However, floodway and levee damages that occurred under the detonation control required over 50 million US$ in repairs, and these costs would have been greatly reduced under a passive control scenario. These results indicate that the detonation control effectively reduced flood stage and the risk of upstream levee failures without increasing flooding extent, building losses, and crop damages, but the potential for floodway erosion and deposition deserves additional consideration in the implementation of a rapid activation design.

Coastal marsh within Mediterranean climate zones is exposed to episodic watershed runoff and sediment loads that occur during storm events. Simulating future marsh accretion under sea level rise calls for attention to: (a) physical processes acting over the time scale of storm events and (b) biophysical processes acting over time scales longer than storm events. Using the upper Newport Bay in Southern California as a case study, we examine the influence of event‐scale processes on simulated change in marsh topography by comparing: (a) a biophysical model that integrates with an annual time step and neglects event‐scale processes (BP‐Annual), (b) a physical model that resolves event‐scale processes but neglects biophysical interactions (P‐Event), and (c) a biophysical model that resolves event‐scale physical processes and biophysical processes at annual and longer time scales (BP‐Event). A calibrated BP‐Event model shows that large (>20‐year return period) episodic storm events are major drivers of marsh accretion, depositing up to 30 cm of sediment in one event. Greater deposition is predicted near fluvial sources and tidal channels and less on marshes further from fluvial sources and tidal channels. In contrast, the BP‐Annual model poorly resolves spatial structure in marsh accretion as a consequence of neglecting event‐scale processes. Furthermore, the P‐Event model significantly overestimates marsh accretion as a consequence of neglecting marsh surface compaction driven by annual scale biophysical processes. Differences between BP‐Event and BP‐Annual models translate up to 20 cm per century in marsh surface elevation. Plain Language Summary: Mediterranean climate zones are characterized by a long dry season and wet season marked by episodic storm systems. Marsh habitat along Mediterranean coastal zones has been dramatically reduced as a result of human development, and future prediction of marsh evolution is needed to support conservation and restoration. Here we develop a new modeling approach to investigate the role of episodic storms versus non‐storm conditions on marsh evolution. Existing biophysical models of marsh evolution poorly represent physical processes which are thought to be the most important drivers of change during storm events, and the proposed modeling approach is used to isolate the role of physical processes during storm events versus coupled biophysical processes that act slowly over non‐storm conditions. With an application of the model in Newport Bay, California, we find that sediment deposition is dominated by storms with return periods of 20 years or longer, which shape the spatial pattern of deposition. We also show the importance of compaction alongside episodic deposition for shaping the future distribution of marsh topography under sea level rise. Key Points: Large storm events (>20 year return period) are primary driver of marsh accretion in Newport BaySpatial distribution of event‐scale deposition controlled by physical processesBiophysical accretion and compaction moderate long‐term change in marsh surface elevation [ABSTRACT FROM AUTHOR]

Investigations are conducted on lifting surfaces with conventional and conformal trailing-edge control surfaces. The Sohngen inversion formula is used with the thin-airfoil integral equation to determine the aerodynamic pressure for various control surface chord-to-airfoil chord ratios. Comparisons to a conventional control surface show increases in lift and pitching moment of the airfoil with a conformal control surface. Aerodynamic pressure distributions acting on a wing with control surfaces are determined with the vortex lattice technique. Predicted aerodynamic pressures and roll moments are compared to available wind-tunnel data and provide a more general understanding of the aerodynamic behavior observed there. Roll performance of a rectangular wing is determined for various control surface chord-to-wing chord ratios. It is found that the maximum roll rate is greater for a wing with a conformal control surface, but has a lower reversal dynamic pressure than the wing with a conventional control surface. The aerodynamic and aeroelastic results obtained from this investigation provide some insight for wings designed with conformal control surfaces.

Enterococci bacteria (ENT) levels in the surf zone at southern California Huntington City and State Beaches are studied to find possible sources of contamination. The main source of ENT is found in a tidal saltwater marsh. Results for environmental factors in the movement of ENT are graphed with a wide array of samples.

Recent improvements in thermoelectric (TE) materials have expanded the potential to use this technology to generate electricity from waste heat in a variety of applications and the performance of the TE generator improves when the temperature difference across the generator is as large as possible given the constraints associated with its application. A thermal switch is used, located physically between the heat source and the TE device, to modulate the heat flow through the TE device.

Examines the upcoming review conference on the Nuclear Non-Proliferation Treaty (NPT) in Geneva August 20-September 14. Cornerstone of system to prevent spread of nuclear weapons; Weaknesses in present system; Purpose of NPT; Other issues; Accomplishments of NPT. INSET: NPT at a glance; Nonproliferation's divided agenda, by J....

Flood extent field observations collected following a wave overtopping event are used to evaluate the accuracy of two urban flood prediction models: a static ('bathtub') model that simply compares water level to land elevation, and a hydrodynamic model that resolves embayment dynamics, overland flow, concrete flood walls, and drainage into the storm water system. Time-dependent overtopping rates were estimated using empirical models parameterized with survey data and local wave heights transformed to the nearshore using Simulating Waves Nearshore (SWAN) and subsequently input to the hydrodynamic model. The hydrodynamic model showed good agreement with field observations, whereas the static model substantially overpredicted flooding suggesting that urban backshore flood depths do not equilibrate with shoreline water levels in transient events. In the absence of a high backwater condition, storm system drainage attenuates wave overtopping flooding. Hydrodynamic model simulations suggest that bay side flood defenses may exacerbate flooding by restricting drainage and that temporary flood mitigation berms can significantly reduce backshore flooding. This study points to a promising urban coastal flood prediction and management framework. [ABSTRACT FROM AUTHOR]

Background: α-Tocopherol ether-linked acetic acid (α-TEA) is a promising agent for cancer prevention/therapy based on its antitumour actions in a variety of cancers.Methods: Human breast cancer cells, MCF-7 and HCC-1954, were used to study the effect of α-TEA using Annexin V/PI staining, western blot analyses, and siRNA knockdown techniques.Results: α-Tocopherol ether-linked acetic acid suppressed constitutively active basal levels of pAKT, pERK, pmTOR, and their downstream targets, as well as induced both cell types to undergo apoptosis. Phosphoinositide 3-kinase (PI3K) inhibitor wortmannin suppressed pAKT, pERK, pmTOR, and their downstream targets, indicating PI3K to be a common upstream mediator. In addition, α-TEA induced increased levels of pIRS-1 (Ser-307), a phosphorylation site correlated with insulin receptor substrate-1 (IRS-1) inactivation, and decreased levels of total IRS-1. Small interfering RNA (siRNA) knockdown of JNK blocked the impact of α-TEA on pIRS-1 and total IRS-1 and impeded its ability to downregulate the phosphorylated status of AKT, ERK, and mTOR. Combinations of α-TEA+MEK or mTOR inhibitor acted cooperatively to induce apoptosis and reduce basal levels of pERK and pmTOR. Importantly, inhibition of MEK and mTOR resulted in increased levels of pAKT and IRS-1, and α-TEA blocked them.Conclusions: Downregulation of IRS-1/PI3K pathways via JNK are critical for α-TEA and α-TEA+MEK or mTOR inhibitor-induced apoptosis in human MCF-7 and HCC-1954 breast cancer cells. [ABSTRACT FROM AUTHOR]