905 resultados para Seismic site response analysis


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The transcription of genes encoding gluconeogenic enzymes is tightly regulated during the perinatal period. These genes are induced by glucagon (cAMP) and glucocorticoids and repressed by insulin. To address the role of cAMP and glucocorticoids in the physiological activation of genes encoding gluconeogenic enzymes in the perinatal period, transgenic mice have been generated with chimeric constructs containing the reporter gene lacZ under the control of hormone response elements. The activity of the transgene is restricted to the liver by the presence of the enhancers from the alpha-fetoprotein gene and its transcription is driven by a promoter that contains a TATA box linked to either cAMP response elements (CREs) or glucocorticoid response elements (GREs). We demonstrate cAMP and glucocorticoid regulation, liver-specific expression, and perinatal activation of the reporter gene. These data indicate that the CRE and GRE are, independently, necessary and sufficient to mediate perinatal gene activation. Perinatal activation was not impaired when a CRE reporter transgene was assayed in mice that contain a targeted mutation of the CRE-binding protein (CREB) gene, providing further evidence for functional redundancy among the members of the CREB/ATF gene family.

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We have explored the feasibility of using a "double-tagging" assay for assessing which amino acids of a protein are responsible for its binding to another protein. We have chosen the adenovirus E1A-retinoblastoma gene product (pRB) proteins for a model system, and we focused on the high-affinity conserved region 2 of adenovirus E1A (CR2). We used site-specific mutagenesis to generate a mutant E1A gene with a lysine instead of an aspartic acid at position 121 within the CR2 site. We demonstrated that this mutant exhibited little binding to pRB by the double-tagging assay. We also have shown that this lack of binding is not due to any significant decrease in the level of expression of the beta-galactosidase-E1A fusion protein. We then created a "library" of phage expressing beta-galactosidase-E1A fusion proteins with a variety of different mutations within CR2. This library of E1A mutations was used in a double-tagging screening to identify mutant clones that bound to pRB. Three classes of phage were identified: the vast majority of clones were negative and exhibited no binding to pRB. Approximately 1 in 10,000 bound to pRB but not to E1A ("true positives"). A variable number of clones appeared to bind equally well to both pRB and E1A ("false positives"). The DNA sequence of 10 true positive clones yielded the following consensus sequence: DLTCXEX, where X = any amino acid. The recovery of positive clones with only one of several allowed amino acids at each position suggests that most, if not all, of the conserved residues play an important role in binding to pRB. On the other hand, the DNA sequence of the negative clones appeared random. These results are consistent with those obtained from other sources. These data suggest that a double-tagging assay can be employed for determining which amino acids of a protein are important for specifying its interaction with another protein if the complex forms within bacteria. This assay is rapid and up to 1 x 10(6) mutations can be screened at one time.

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Fractal antennas have been proposed to improve the bandwidth of resonant structures and optical antennas. Their multiband characteristics are of interest in radiofrequency and microwave technologies. In this contribution we link the geometry of the current paths built-in the fractal antenna with the spectral response. We have seen that the actual currents owing through the structure are not limited to the portion of the fractal that should be geometrically linked with the signal. This fact strongly depends on the design of the fractal and how the different scales are arranged within the antenna. Some ideas involving materials that could actively respond to the incoming radiation could be of help to spectrally select the response of the multiband design.

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Understanding spatial distributions and how environmental conditions influence catch-per-unit-effort (CPUE) is important for increased fishing efficiency and sustainable fisheries management. This study investigated the relationship between CPUE, spatial factors, temperature, and depth using generalized additive models. Combinations of factors, and not one single factor, were frequently included in the best model. Parameters which best described CPUE varied by geographic region. The amount of variance, or deviance, explained by the best models ranged from a low of 29% (halibut, Charlotte region) to a high of 94% (sablefish, Charlotte region). Depth, latitude, and longitude influenced most species in several regions. On the broad geographic scale, depth was associated with CPUE for every species, except dogfish. Latitude and longitude influenced most species, except halibut (Areas 4 A/D), sablefish, and cod. Temperature was important for describing distributions of halibut in Alaska, arrowtooth flounder in British Columbia, dogfish, Alaska skate, and Aleutian skate. The species-habitat relationships revealed in this study can be used to create improved fishing and management strategies.

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This paper presents a structural analysis of a masonry chimney built in the 1940s, which is currently being cataloged as local interest heritage. This structure has not served any industrial purpose for the last thirty years. The chimney is located in the town of Agost (Alicante - Spain) and directly exposed to the prevailing winds from the sea, as it is approximately 12 km away from the waterfront and there are not any significant barriers, which could protect the structure against the wind. There are longitudinal cracks and fissures all along the shaft because of the chimney’s geometrical characteristics, the effect of the masonry creep and especially the lack of maintenance. Moreover, there is also a permanent bending deformation in the upper 1/3 of the height due to the wind pressure. A numerical analysis for the static behavior against gravity and wind loads was performed using the structure’s current conditions after a detailed report of its geometry, its construction system and the cracking pattern. Afterwards, the dynamic behavior was studied, i.e. a seismic analysis using both response spectra and accelerograms in order to examine the structural stability. This work shows the pre-monitoring analysis before any experimental testing. Using the current results the future test conditions will be determined (e.g. number of sensors and monitoring point location, excitation systems, etc) prior to a possible structural reinforcement by applying composite material (fiber reinforced polymers).

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A MATLAB-based computer code has been developed for the simultaneous wavelet analysis and filtering of multichannel seismic data. The considered time–frequency transforms include the continuous wavelet transform, the discrete wavelet transform and the discrete wavelet packet transform. The developed approaches provide a fast and precise time–frequency examination of the seismograms at different frequency bands. Moreover, filtering methods for noise, transients or even baseline removal, are implemented. The primary motivation is to support seismologists with a user-friendly and fast program for the wavelet analysis, providing practical and understandable results.

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We present a disposable optical sensor for Ascorbic Acid (AA). It uses a polyaniline based electrochromic sensing film that undergoes a color change when exposed to solutions of ascorbic acid at pH 3.0. The color is monitored by a conventional digital camera working with the hue (H) color coordinate. The electrochromic film was deposited on an Indium Tin Oxide (ITO) electrode by cyclic voltammetry and then characterized by atomic force microscopy, electrochemical and spectroscopic techniques. An estimation of the initial rate of H, as ΔH/Δt, is used as the analytical parameter and resulted in the following logarithmic relationship: ΔH/Δt = 0.029 log[AA] + 0.14, with a limit of detection of 17 μM. The relative standard deviation when using the same membrane 5 times was 7.4% for the blank, and 2.6% (for n = 3) on exposure to ascorbic acid in 160 μM concentration. The sensor is disposable and its applicability to pharmaceutical analysis was demonstrated. This configuration can be extended for future handheld configurations.

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Background. Health care professionals, especially those working in primary health-care services, can play a key role in preventing and responding to intimate partner violence. However, there are huge variations in the way health care professionals and primary health care teams respond to intimate partner violence. In this study we tested a previously developed programme theory on 15 primary health care center teams located in four different Spanish regions: Murcia, C Valenciana, Castilla-León and Cantabria. The aim was to identify the key combinations of contextual factors and mechanisms that trigger a good primary health care center team response to intimate partner violence. Methods. A multiple case-study design was used. Qualitative and quantitative information was collected from each of the 15 centers (cases). In order to handle the large amount of information without losing familiarity with each case, qualitative comparative analysis was undertaken. Conditions (context and mechanisms) and outcomes, were identified and assessed for each of the 15 cases, and solution formulae were calculated using qualitative comparative analysis software. Results. The emerging programme theory highlighted the importance of the combination of each team’s self-efficacy, perceived preparation and women-centredness in generating a good team response to intimate partner violence. The use of the protocol and accumulated experience in primary health care were the most relevant contextual/intervention conditions to trigger a good response. However in order to achieve this, they must be combined with other conditions, such as an enabling team climate, having a champion social worker and having staff with training in intimate partner violence. Conclusions. Interventions to improve primary health care teams’ response to intimate partner violence should focus on strengthening team’s self-efficacy, perceived preparation and the implementation of a woman-centred approach. The use of the protocol combined with a large working experience in primary health care, and other factors such as training, a good team climate, and having a champion social worker on the team, also played a key role. Measures to sustain such interventions and promote these contextual factors should be encouraged.

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The first well logs collected below the Antarctic circle were obtained during Leg 113 at Site 693 on the Dronning Maud Land Margin (Antarctica) in the Weddell Sea. Gamma-ray, resistivity, and sonic logs were collected between 108.0 and 439.0 mbsf. The downhole logs show good agreement with the data collected from cores and provide a continuous measurement of the sedimentary record. These continuous log records show that the rather uniform Tertiary lithology seen in cores is characterized by high-frequency variability in the log data. Several thin hard streaks are identified, the largest of which coincides with a major Miocene hiatus. Associated with this hiatus is a change to lower illite content (and correspondingly lower gamma-ray counts) and to a significant increase in diatom content. Spectral analysis of the logs was performed on the lower Pliocene through upper Oligocene interval (108.0-343.0 mbsf). Between 108.0 and 245.0 mbsf, average sedimentation rates (50 and 26 m/m.y.) are high enough to show that variance is present in the orbital eccentricity (~95 k.y.) and obliquity (~41 k.y.) bands. Between 253.0 and 343.0 mbsf, the sedimentation rate (8 m/m.y.) is too low to resolve high frequency variations. The Milankovitch frequencies are best developed in the resistivity logs. Resistivity is responding to changes in porosity, which in these sediments is controlled by the abundance of biosiliceous sediments, particularly diatoms. The orbital forcing suggested by the Milankovitch frequencies may be influencing diatom productivity by inducing oscillations in upwelling, ice coverage, pack ice, and/or polynya. Although variations in diatom abundance were observed in the cores, they were not attributed to a Milankovitch signal, and therefore in this environment, downhole logs are an important contribution to the detection and understanding of orbitally influenced changes in sedimentation.

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Twenty four core samples from CRP-1, seven from Quaternary strata (20-43.55 meters below sea floor or mbsf) and seventeen from early Miocene strata (43.55 to 147.69 mbsf), have been analysed for their grain-size distribution using standard sieve and Sedigraph techniques. The results are in good agreement with estimates of texture made as part of the visual core description for the 1 :20 core logs for CRP-1 (Cape Roberts Science Team, 1998). Interpretation of the analyses presented here takes into account the likely setting of the site in Quaternary times as it is today, with CRP-1 high on the landward flank of a well-defined submarine ridge rising several hundred metres above basins on either side. In contrast, seismic geometries for strata deposited in early Miocene times indicate a generally planar sea floor dipping gently seaward. Fossils from these strata indicate shallow water depths (< 100 m), indicating the possibility that waves and tidal currents may have influenced sea floor sediments. The sediments analysed here are considered in terms of 3 textural facies: diamict, mud (silt and clay) and sand. Most of the Quaternary section but only 30% of the early Miocene section is diamict, a poorly sorted mixture of sand and mud with scattered clasts, indicating little wave or current influence on its texture. Although not definitive, diamict textures and other features suggest that the sediment originated as basal glacial debris but has been subsequently modified by minor winnowing, consistent with the field interpretation of this facies as ice-proximal and distal glaciomarine sediment. Sediments deposited directly from glacier ice appear to be lacking. Mud facies sediments, which comprise only 10% of the Quaternary section but a third of the early Miocene section, were deposited below wave base and largely from suspension, and show features (described elsewhere in this volume) indicative of the influence of both glacial and sediment gravity flow processes. Sand facies sediments have a considerable proportion of mud, normally more than 20%, but a well-sorted fine-very fine sand fraction. In the context of the early Miocene coastal setting we interpret these sediments as shoreface sands close to wave base.