Geochemical Characteristics of Volcanism on the Azores

Ocean islands are ideal research areas for petrologists because of their volcanic origins and the geochemical information they reveal of the mantle underneath. The Azores archipelago is no exception, lying within a unique geological setting which contains a mantle plume as well as tectonic plate boundary movement. Supported by these facts, the islands are an interesting and valuable place to study igneous petrology. By using major oxide data from the separate Azores, variation diagrams can be produced to display trends between different chemical ratios. Differences or similarities seen can be attributed to magma mixing, the complex plumbing system of the mantle plume, and the geographic placement of the islands near major tectonic features.No embarg

Photoregulation of the binding of a synthetic polyelectrolyte to phosphatidylcholine bilayer membranes

We describe in the present paper the use of a photosensitive polyelectrolyte to effect photoregulation of the structure and permeability of phosphatidylcholine vesicle membrane

Reduced graphene oxide supported piperazine in aminocatalysis

Reduced graphene oxide (rGO) has been used as a support for piperazine to provide heterogeneous bifunctional organocatalyst (rGO-NH) that is able to efficiently promotvintage organic transformations such as Knoevenagel, Michael and aldol reactions. The obtained results suggest a significant role of the support in the course of these reactionsWe thank the Spanish Government (CTQ-2012-35957) and CAM (AVANCAT CS2009/PPQ-1634) for financial support. E.R. thanks the Spanish Ministry for a predoctoral fellowship (FPU/AP-2010-0807). R.S. thanks the Spanish Ministry of Science for a postdoctoral contract (PTQ-11-04601

Effects on High Plasticity Clay Deposits On Site Ground Amplification

This paper reviews the effects of the Lorna Prieta earthquake on Treasure Island and discusses previous studies of site ground motion amplification. An independent study was performed in which it is shown that the site amplification is attributable to the presence of the Bay Mud deposits, a high plasticity silty clay that exhibits higher than normal shear modulus with cyclic strain. There is a similarity with the Mexico City clay deposits in both high plasticity and site amplification. Engineers should be alert to high plasticity clay deposits as a potential source of ground motion amplification

Ground Motion Amplification Using Microseisms

This paper discusses the use of microseism measurement as a tool to predict local site amplification. Systems analysis techniques can be applied to the microseism data to validate site properties used in wave propagation analysis. Spectral ratio was found to be inversely related to peak rock velocity for soft sites. Microseisms can be used on a normalized basis to extend spatial response information

Soil-Structure Interaction at the Waterfront

The Navy, forced by its mission to locate at the waterfront, often on loose, saturated cohesionless soils, faces a severe liquefaction threat. Research has been in progress to evaluate the Princeton University Effective Stress Soil Model. This paper discusses that model and presents a validation example study comparing model predictions with a centrifuge experiment

Site Analysis for Seismic Soil Liquefaction Potential

Field penetration data and cyclic laboratory test data are presented for evaluating the seismically induced soil liquefaction potential at a waterfront site. Dynamic split-spoon penetration recordings and three types of quasistatic friction cone probings were made. The friction cones were the standard mechanical cone, the electric cone, and the piezometric cone. The latter penetrometer has a porous element near the tip which permits measurement of pore water pressures generated during penetration. By interrupting penetration, the rate of pore pressure dissipation can be recorded, so an estimate of soil permeability can also be derived. Undisturbed samples were taken using an Osterberg piston sampler, and the specimens were subjected to cyclic triaxial testing in the laboratory. The field sounding techniques were in agreement; however, they indicated a recently deposited sensitive silty sand to have a liquefaction resistance approximately one-half that based upon cyclic triaxial testing. The question arises as to whether the liquefaction resistance as determined by laboratory testing is more appropriate herein, or whether behavior suggested by the penetration test results more realistically predicts the response of this type of soil to an actual earthquake

Analysis of general and mathematical domain prerequisites: a longitudinal study in the last year of kindergarten

openAttraverso l'utilizzo della batteria PRCR-3, il presente lavoro punta a valutare l'evoluzione dei prerequisiti del calcolo in bambini dell'ultimo anno della scuola dell'infanzia, ipotizzando di osservare un cambiamento tra la prima somministrazione e la seconda somministrazione, svolte rispettivamente ad inizio e a fine anno scolastico. Inoltre, viene svolta un analisi per osservare la correlazione tra i diversi domini dei prerequisiti del calcolo indagati, alle prove relative ad abilità dominio generali e attività di home numeracy, valutate attraverso un questionario compilato dai genitori