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The aim of this study was to apply Nakamura's technique to Valencia city center, after some preliminary tests in Barcelona. Previous studies of Barcelona had measured periods in restrictive conditions and in various types of material ranging from very soft soil (with a predominant period of approximately 2 s) to rock (0.3 s), and under different measurement conditions. The Valencia city center measurements were taken by using the distance from buildings and car and pedestrian traffic to construct a measurement grid that was as regular as possible. We also estimated possible soil-structure interaction to detect potential vulnerability. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes an integrated near-surface geophysical study carried out in order to obtain high-resolution images of the shallow subsurface under and around the Cathedral of Mallorca. The study was a part of a global project focused on determining the state of the building structure and on evaluating the Cathedral''s dynamical behaviour (natural frequencies and vibration modes). Ground-penetrating radar (GPR) and the capacitively coupled resistivity method were used to obtain 2D images of the shallow subsurface. Refraction microtremor array measurements (ReMi) were also used to characterize the rock and soil properties and several invasive boreholes provided detailed and exact information on the stratigraphy. The information from the geophysical data was used to determine a final model of the ground, with indications of the most likely vulnerable zones. As a part of this final model, GPR profiles enabled us to delineate the superficial ground structure and to detect some archaeological features. Electrical resistivity imaging data were in good agreement with the GPR results, and showed shallow major changes in the soil and rock under the filling materials. The refraction microtremor array (ReMi) results indicate the existence of compacted soils in different areas, probably corresponding to old filled zones, in good correlation with GPR and resistivity profiles in the most superficial part of the ground. [Copyright &y& Elsevier]

Abstract: Historical and heritage buildings have been remodelled lots of times in his large history, especially for old private ones. For some years these historical buildings have been used for other public o private uses than the one which were designed. Especially important are the remodelling carried out during the last few decades, using extensively concrete. These changes to adapt and restore the structures were performed in order to develop specific uses and, generally, they are not enough documented. The modifications made and the changes in the employ of these buildings also alter their structural behaviour, which must be calculated when new functions of the structures are considered. In this way, it is required the knowledge of the structural inner elements. The analysis of this kind of constructions has to preserve the integrity of the old remaining elements. Hence, non-destructive techniques have to be applied in order to determine exactly the old elements, the new ones and to determine the different components of the buildings. Now a day, high frequency radar techniques has been enough improved to be use to acquire a high confidentially, accurate and precise information about all these different elements and different parts of the structure. In this work we present a case study of the high frequency radar techniques applied to a S. XV building that was remodelled in several times. The last change was carried out during the 60 decade of the last century. In this arrangement, it is supposed that almost all the floors were replaced by a beam-flooring blocks structure. The GPR data obtained in the survey allow determining the specific zones affected by this last remodel work that affects mainly the floors of the first and second level of the building. It was also possible to determine the typology of the constructive elements and pieces, detecting some of the bars inside the beams. We also have detected some oldest structural change and the adopted solutions. Finally, results allow us to separate the different zones of the building depending on the structural elements supporting the floor. [Copyright &y& Elsevier]

Simultaneous field measurements were carried out across the Ebro delta inner shelf using two instrumented bottom boundary layer tripods deployed at 8.5 and 12.5 m water depth. The period analysed corresponds to the transition from fair-weather to wave-storm conditions. The recorded data show that the sediment resuspension was associated with the increases in wave activity (“skin” wave shear stress) and started simultaneously at both study sites. Wave and current related parameters and the concentration of suspended sediment reflect an increasing trend towards the shallower location. The measured profile of suspended sediment concentration agrees well with exponential and power deterministic models. The estimated resuspension coefficient (γ0) shows temporal and spatial variability, although average values (4–6×10−3) are near the “typical” resuspension parameter previously defined for rippled bottom conditions (2×10−3). [Copyright &y& Elsevier]

Near-bottom sediment fluxes were measured at several locations across the Ebro continental shelf during the FANS Project. Moored current meters and transmissometers were installed near the bottom at 12, 60 and 100 m water depth. Measurements of near-bottom currents and water turbidity in combination with wave data provided information about physical forcing and resulting resuspension and sediment fluxes on this Mediterranean continental shelf. Mean near-bottom sediment fluxes decrease sharply (by one to two orders of magnitude) from the inner to the mid-shelf and more gradually from the mid- to the outer shelf. The resulting near-bottom sediment fluxes are towards the SW and the alongshelf fluxes are about one order of magnitude higher than the across-shelf fluxes. Maximum near-bottom sediment fluxes occur by sediment resuspension on the inner shelf during storm events when wave shear stress increases. Wave shear stresses decrease with depth and sediment resuspension by waves occurs quite often (about 30% of the time) on the inner shelf, very sporadically (<0.5% of the time) on the mid-shelf (during the strongest storms) and never on the outer shelf. Near-bottom currents can resuspend bottom sediment only on the inner shelf, although very sporadically (<0.5% of the time). The lowest mean current shear stress is on the mid-shelf, where wave shear stresses are insignificant most of the time and finer sediment accumulates. On the outer shelf, the current shear stress increases, causing the winnowing of fine sediments and preventing the relict transgressive sands from being covered by mud. These conditions differ from those of shelves with strong tides and long period waves, where resuspension by waves reaches the outer shelf and the across- and alongshelf sediment fluxes have the same order of magnitude. [Copyright &y& Elsevier]

The genetic and biochemical basis of fish-eye disease (FED) was investigated in a 63-year-old female proband with low plasma HDL cholesterol. Analyses of corneal and plasma lipids of the proband were consistent with impaired lecithin:cholesterol acyltransferase (LCAT) activity. Free cholesterol and phospholipid levels were elevated relative to control values, whereas cholesteryl ester levels were greatly reduced. Fatty acid compositions of corneal lipids from the proband and control subjects differ from the respective fatty acid compositions of their plasma lipids. This suggests that the metabolic pathways and acyl chain specificities for phospholipid, cholesteryl ester, and triglyceride metabolism within the cornea are distinct from those of plasma. Sequencing of the LCAT gene from the proband revealed a novel mutation at nucleotide 399, corresponding to an Arg99-->Cys substitution. Secretion of LCAT (Arg99-->Cys) by transfected COS-6 cells was approximately 50% of that of the wild type, but its specific activity against reassembled HDL was 93% lower than that of wild-type LCAT. The specific activities of wild-type and LCAT (Arg99-->Cys) against LDL were reduced similarly, suggesting that the appearance of the FED phenotype does not require enhanced activity against LDL. Our data support the hypothesis that FED is a partial LCAT deficiency in which poor esterification in specific types of HDL particles may contribute to the appearance of the corneal opacities.