Model Tests on Seismic Stability of an Approach Fill Embankment, Annacis Island Bridge Project, Vancouver, Canada

This paper describes a study performed to evaluate the seismic behaviour of a 10 m high bridge end sand fill placed upon soft organic foundation soils and supported on piles. Under static conditions the fill load is essentially carried by the piles by arching action , and little deformation was observed to occur in the field. The results of both model tests and finite element analysis are in agreement with this finding. Concern arose as to the likely response of this structure under earthquake loading and a model sand embankment supported on 400 model piles was built and tested on the shake table. The model and testing procedures are described in some detail in the paper. The results of the shaking table study indicate that during shaking the load is transferred from the piles onto the foundation resulting in large deformations of the fill. Analysis of the model tests based on this assumption gave deformations that were in good agreement with observed settlements. A similar analysis of the prototype indicates that seismic loading sufficient to cause such transfer would result in a settlement of the fill of about 0.4m, and that deformation would cease once the shaking stopped

Salicylaldehyde hydrazones: buttressing of outer sphere hydrogen-bonding and copper-extraction properties

Salicylaldehyde hydrazones are weaker copper extractants than their oxime derivatives, which are used in hydrometallurgical processes to recover ~20 % of the world’s copper. Their strength, based on the extraction equilibrium constant Ke, can be increased by nearly three orders of magnitude by incorporating electron-withdrawing or hydrogen-bond acceptor groups (X) ortho to the phenolic OH group of the salicylaldehyde unit. Density functional theory calculations suggest that the effects of the 3-X substituents arise from a combination of their influence on the acidity of the phenol in the pH-dependent equilibrium, Cu2+ + 2Lorg ⇌ [Cu(L–H)2]org + 2H+, and on their ability to ‘buttress’ interligand hydrogen bonding by interacting with the hydrazone N–H donor group. X-ray crystal structure determination and computed structures indicate that in both the solid state and the gas phase, coordinated hydrazone groups are less planar than coordinated oximes and this has an adverse effect on intramolecular hydrogen-bond formation to the neighbouring phenolate oxygen atoms

Breaking down the barrier: dispersal across the Antarctic Polar Front

Our view of the Antarctic Polar Front (APF) as a circum-polar biogeographic barrier is changing (Chown et al. 2015). The APF marks the convergent boundary between cold Antarctic water and warmer sub-Antarctic water, and has long been considered to prevent north-south dispersal in the Southern Ocean (reviewed by Clarke et al. 2005, Fraser et al. 2012). Our multi-year survey data provides evidence that rafting organisms readily cross the APF

Differential retinoic acid signaling in the hippocampus of aged rats with and without memory impairment

Funding Information: This work was entirely supported by the Intramural Research Program of the National Institutes of Health, National institute on Aging.Peer reviewedPublisher PD

La Proteómica como vía para determinar el origen animal de los productos cárnicos

Comunicaciones a congreso

Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease

Funded by Wellcome Trust Translational Award SNBTSPeer reviewedPublisher PD

Structure and Emergence of Specific Olfactory Glomeruli in the Mouse

Olfactory sensory neurons (OSNs) expressing a given odorant receptor (OR) gene project their axons to a few specific glomeruli that reside at recognizable locations in the olfactory bulb. Connecting ∼1000 populations of OSNs to the ∼1800 glomeruli of the mouse bulb poses a formidable wiring problem. Additional progress in understanding the mechanisms of neuronal connectivity is dependent on knowing how these axonal pathways are organized and how they form during development. Here we have applied a genetic approach to this problem. We have constructed by gene targeting novel strains of mice in which either all OSNs or those that express a specific OR gene, M72 or M71, also produce green fluorescent protein (GFP) or a fusion of tau with GFP. We visualized OSNs and their axons in whole mounts with two-photon laser scanning microscopy. The main conclusion we draw from the three-dimensional reconstructions is the high degree of morphological variability of mature glomeruli receiving axonal input from OR-expressing OSNs and of the pathways taken by the axons to those glomeruli. We also observe that axons of OR-expressing OSNs do not innervate nearby glomeruli in mature mice. Postnatally, a tangle of axons from M72-expressing OSNs occupies a large surface area of the bulb and coalesces abruptly into a protoglomerulus at a reproducible stage of development. These results differ in several aspects from those reported for the development of glomeruli receiving input from OSNs expressing the P2 OR, suggesting the need for a more systematic examination of OR-specific glomeruli