52 resultados para Wave Run-up

em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain


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We analyse the variations produced on tsunami propagation and impact over a straight coastline because of the presence of a submarine canyon incised in the continental margin. For ease of calculation we assume that the shoreline and the shelf edge are parallel and that the incident wave approaches them normally. A total of 512 synthetic scenarios have been computed by combining the bathymetry of a continental margin incised by a parameterised single canyon and the incident tsunami waves. The margin bathymetry, the canyon and the tsunami waves have been generated using mathematical functions (e.g. Gaussian). Canyon parameters analysed are: (i) incision length into the continental shelf, which for a constant shelf width relates directly to the distance from the canyon head to the coast, (ii) canyon width, and (iii) canyon orientation with respect to the shoreline. Tsunami wave parameters considered are period and sign. The COMCOT tsunami model from Cornell University was applied to propagate the waves across the synthetic bathymetric surfaces. Five simulations of tsunami propagation over a non-canyoned margin were also performed for reference. The analysis of the results reveals a strong variation of tsunami arrival times and amplitudes reaching the coastline when a tsunami wave travels over a submarine canyon, with changing maximum height location and alongshore extension. In general, the presence of a submarine canyon lowers the arrival time to the shoreline but prevents wave build-up just over the canyon axis. This leads to a decrease in tsunami amplitude at the coastal stretch located just shoreward of the canyon head, which results in a lower run-up in comparison with a non-canyoned margin. Contrarily, an increased wave build-up occurs on both sides of the canyon head, generating two coastal stretches with an enhanced run-up. These aggravated or reduced tsunami effects are modified with (i) proximity of the canyon tip to the coast, amplifying the wave height, (ii) canyon width, enlarging the areas with lower and higher maximum height wave along the coastline, and (iii) canyon obliquity with respect to the shoreline and shelf edge, increasing wave height shoreward of the leeward flank of the canyon. Moreover, the presence of a submarine canyon near the coast produces a variation of wave energy along the shore, eventually resulting in edge waves shoreward of the canyon head. Edge waves subsequently spread out alongshore reaching significant amplitudes especially when coupling with tsunami secondary waves occurs. Model results have been groundtruthed using the actual bathymetry of Blanes Canyon area in the North Catalan margin. This paper underlines the effects of the presence, morphology and orientation of submarine canyons as a determining factor on tsunami propagation and impact, which could prevail over other effects deriving from coastal configuration.

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La conca del riu Quiroz, al nord del Perú, està influenciada per dues zones d’endemisme d’aus i conté quatre àrees importants per a la conservació d’aus. Malgrat això, la informació sobre l’avifauna present a la conca és poc coneguda ja que no s’ha realitzat, fins al moment, cap estudi avifaunístic del global de la conca. En aquest estudi s’han mostrejat nou zones de la conca. A cadascuna s’ha valorat el potencial per al desenvolupament de l’aviturisme i la seva importància per a la conservació de les aus. A més, s’ha calculat un índex que permet valorar l’aviturisme i la conservació conjuntament. Els mostrejos realitzats a la conca demostren la seva riquesa avifaunística doncs, en una superfície mostrejada de 684ha, s’hi han reportat 151 espècies de les quals 34 són endèmiques i 7 estan catalogades com a amenaçades. Al llarg de la conca s’han identificat tres zones amb una importància ornitològica per damunt de la resta. Suyo és la zona de la conca amb un potencial aviturístic més elevat. ChinChin, el lloc amb més importància i possibilitats de dur a terme actuacions encaminades a la conservació. Yanta, destaca en ambdós sentits sent el desenvolupament de l’aviturisme la millor alternativa per garantir la conservació de la zona i, en especial, la seva diversitat avifaunistica.

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Avalanche hazard maps of high accuracy are difficult to produce. For land-use planning and management purposes, a good knowledge of extreme run-out zones and frequencies of avalanches is required. In the present work, vegetation recognition (especially focused on Pinus uncinata trees) and dendrochronological techniques are used to characterize avalanches that have occurred in historical times, helping to determine both the extent of large or extreme avalanches and their occurrence in time. Vegetation was studied at the Canal del Roc Roig (eastern Pyrenees, Spain) avalanche path. The avalanches descending this path affect the railway that reaches the Vall de Núria resort and the run-up to the opposite slope. During winter 1996, two important avalanches affecting this path were well documented. These are compared with the results of the vegetation study, consisting of an inventory of flora, the recording of vegetation damages along eight transverse profiles at different altitudes on the path and a dendrochronological sampling campaign. The data obtained contributed to a characterization of the predominant snow accumulation in the starting zone, the 1996 avalanches and the range of frequencies of large avalanches. Also, traces of avalanches that increase the path mapped in the avalanche paths map published by the Institut Cartogràfic de Catalunya in 2000 were identified, improving the initial existing information.

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Avalanche hazard maps of high accuracy are difficult to produce. For land-use planning and management purposes, a good knowledge of extreme run-out zones and frequencies of avalanches is required. In the present work, vegetation recognition (especially focused on Pinus uncinata trees) and dendrochronological techniques are used to characterize avalanches that have occurred in historical times, helping to determine both the extent of large or extreme avalanches and their occurrence in time. Vegetation was studied at the Canal del Roc Roig (eastern Pyrenees, Spain) avalanche path. The avalanches descending this path affect the railway that reaches the Vall de Núria resort and the run-up to the opposite slope. During winter 1996, two important avalanches affecting this path were well documented. These are compared with the results of the vegetation study, consisting of an inventory of flora, the recording of vegetation damages along eight transverse profiles at different altitudes on the path and a dendrochronological sampling campaign. The data obtained contributed to a characterization of the predominant snow accumulation in the starting zone, the 1996 avalanches and the range of frequencies of large avalanches. Also, traces of avalanches that increase the path mapped in the avalanche paths map published by the Institut Cartogràfic de Catalunya in 2000 were identified, improving the initial existing information.

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Los requisitos de los dispositivos empleados en los nuevos sistemas de telecomunicaciones son: unas avanzadas prestaciones, reducido tamaño y bajo coste. Actualmente, se utilizan filtros basados en la tecnología SAW para trabajar a frecuencias de microondas. Dado los inconvenientes que presentan dicho tipo de filtros, se pretende substituirlos por filtros basados en tecnología BAW. La topología en escalera es hasta el momento la más extendida para diseñar estos filtros.

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A generalization of reaction-diffusion models to multigeneration biological species is presented. It is based on more complex random walks than those in previous approaches. The new model is developed analytically up to infinite order. Our predictions for the speed agree to experimental data for several butterfly species better than existing models. The predicted dependence for the speed on the number of generations per year allows us to explain the change in speed observed for a specific invasion

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The relativistic distorted-wave Born approximation is used to calculate differential and total cross sections for inner shell ionization of neutral atoms by electron and positron impact. The target atom is described within the independent-electron approximation using the self-consistent Dirac-Fock-Slater potential. The distorting potential for the projectile is also set equal to the Dirac-Fock-Slater potential. For electrons, this guarantees orthogonality of all the orbitals involved and simplifies the calculation of exchange T-matrix elements. The interaction between the projectile and the target electrons is assumed to reduce to the instantaneous Coulomb interaction. The adopted numerical algorithm allows the calculation of differential and total cross sections for projectiles with kinetic energies ranging from the ionization threshold up to about ten times this value. Algorithm accuracy and stability are demonstrated by comparing differential cross sections calculated by our code with the distorting potential set to zero with equivalent results generated by a more robust code that uses the conventional plane-wave Born approximation. Sample calculation results are presented for ionization of K- and L-shells of various elements and compared with the available experimental data.

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A general formalism is set up to analyze the response of an arbitrary solid elastic body to an arbitrary metric gravitational wave (GW) perturbation, which fully displays the details of the interaction antenna wave. The formalism is applied to the spherical detector, whose sensitivity parameters are thereby scrutinized. A multimode transfer function is defined to study the amplitude sensitivity, and absorption cross sections are calculated for a general metric theory of GW physics. Their scaling properties are shown to be independent of the underlying theory, with interesting consequences for future detector design. The GW incidence direction deconvolution problem is also discussed, always within the context of a general metric theory of the gravitational field.

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The Hartman effect is analyzed in both the position and momentum representations of the problem. The importance of Wigner tunneling and deep tunneling is singled out. It is shown quantitatively how the barrier acts as a filter for low momenta (quantum speed up) as the width increases, and a detailed mechanism is proposed. Superluminal transmission is also discussed.

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The article presents and discusses long-run series of per capita GDP and life expectancy for Italy and Spain (1861-2008). After refining the available estimates in order to make them comparable and with the avail of the most up-to-date researches, the main changes in the international economy and in technological and sociobiological regimes are used as analytical frameworks to re-assess the performances of the two countries; then structural breaks are searched for and Granger causality between the two variables is investigated. The long-run convergence notwithstanding, significant cyclical differences between the two countries can be detected: Spain began to modernize later in GDP, with higher volatility in life expectancy until recent decades; by contrast, Italy showed a more stable pattern of life expectancy, following early breaks in per capita GDP, but also a negative GDP break in the last decades. Our series confirm that, whereas at the early stages of development differences in GDP tend to mirror those in life expectancy, this is no longer true at later stages of development, when, if any, there seems to be a negative correlation between GDP and life expectancy: this finding is in line with the thesis of a non-monotonic relation between life expectancy and GDP and is supported by tests of Granger causality.

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The chapter presents up-to-date estimates of Italy’s regional GDP, with the present borders, in ten-year benchmarks from 1871 to 2001, and proposes a new interpretative hypothesis based on long-lasting socio-institutional differences. The inverted U-shape of income inequality is confirmed: rising divergence until the midtwentieth century, then convergence. However, the latter was limited to the centrenorth: Italy was divided into three parts by the time regional inequality peaked, in 1951, and appears to have been split into two halves by 2001. As a consequence of the falling back of the south, from 1871 to 2001 we record σ-divergence across Italy’s regions, i.e. an increase in dispersion, and sluggish β-convergence. Geographical factors and the market size played a minor role: against them are both the evidence that most of the differences in GDP are due to employment rather than to productivity and the observed GDP patterns of many regions. The gradual converging of regional GDPs towards two equilibria instead follows social and institutional differences − in the political and economic institutions and in the levels of human and social capital – which originated in pre-unification states and did not die (but in part even increased) in postunification Italy.

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BACKGROUND: Studies in bipolar disorder (BD) to date are limited in their ability to provide a whole-disease perspective--their scope has generally been confined to a single disease phase and/or a specific treatment. Moreover, most clinical trials have focused on the manic phase of disease, and not on depression, which is associated with the greatest disease burden. There are few longitudinal studies covering both types of patients with BD (I and II) and the whole course of the disease, regardless of patients' symptomatology. Therefore, the Wide AmbispectiVE study of the clinical management and burden of Bipolar Disorder (WAVE-bd) (NCT01062607) aims to provide reliable information on the management of patients with BD in daily clinical practice. It also seeks to determine factors influencing clinical outcomes and resource use in relation to the management of BD. METHODS: WAVE-bd is a multinational, multicentre, non-interventional, longitudinal study. Approximately 3000 patients diagnosed with BD type I or II with at least one mood event in the preceding 12 months were recruited at centres in Austria, Belgium, Brazil, France, Germany, Portugal, Romania, Turkey, Ukraine and Venezuela. Site selection methodology aimed to provide a balanced cross-section of patients cared for by different types of providers of medical aid (e.g. academic hospitals, private practices) in each country. Target recruitment percentages were derived either from scientific publications or from expert panels in each participating country. The minimum follow-up period will be 12 months, with a maximum of 27 months, taking into account the retrospective and the prospective parts of the study. Data on demographics, diagnosis, medical history, clinical management, clinical and functional outcomes (CGI-BP and FAST scales), adherence to treatment (DAI-10 scale and Medication Possession Ratio), quality of life (EQ-5D scale), healthcare resources, and caregiver burden (BAS scale) will be collected. Descriptive analysis with common statistics will be performed. DISCUSSION: This study will provide detailed descriptions of the management of BD in different countries, particularly in terms of clinical outcomes and resources used. Thus, it should provide psychiatrists with reliable and up-to-date information about those factors associated with different management patterns of BD. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01062607.

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Hydrogenated amorphous silicon (a‐Si:H) thin films have been obtained from pure SiH4 rf discharges by using the square wave modulation (SQWM) method. Film properties have been studied by means of spectroellipsometry, thermal desorption spectrometry, photothermal deflection spectroscopy and electrical conductivity measurements, as a function of the modulation frequency of the rf power amplitude (0.2-4000 Hz). The films deposited at frequencies about 1 kHz show the best structural and optoelectronic characteristics. Based upon the experimental results, a qualitative model is presented, which points up the importance of plasma negative ions in the deposition of a‐Si:H from SQWM rf discharges through their influence on powder particle formation.

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BACKGROUND: Studies in bipolar disorder (BD) to date are limited in their ability to provide a whole-disease perspective--their scope has generally been confined to a single disease phase and/or a specific treatment. Moreover, most clinical trials have focused on the manic phase of disease, and not on depression, which is associated with the greatest disease burden. There are few longitudinal studies covering both types of patients with BD (I and II) and the whole course of the disease, regardless of patients' symptomatology. Therefore, the Wide AmbispectiVE study of the clinical management and burden of Bipolar Disorder (WAVE-bd) (NCT01062607) aims to provide reliable information on the management of patients with BD in daily clinical practice. It also seeks to determine factors influencing clinical outcomes and resource use in relation to the management of BD. METHODS: WAVE-bd is a multinational, multicentre, non-interventional, longitudinal study. Approximately 3000 patients diagnosed with BD type I or II with at least one mood event in the preceding 12 months were recruited at centres in Austria, Belgium, Brazil, France, Germany, Portugal, Romania, Turkey, Ukraine and Venezuela. Site selection methodology aimed to provide a balanced cross-section of patients cared for by different types of providers of medical aid (e.g. academic hospitals, private practices) in each country. Target recruitment percentages were derived either from scientific publications or from expert panels in each participating country. The minimum follow-up period will be 12 months, with a maximum of 27 months, taking into account the retrospective and the prospective parts of the study. Data on demographics, diagnosis, medical history, clinical management, clinical and functional outcomes (CGI-BP and FAST scales), adherence to treatment (DAI-10 scale and Medication Possession Ratio), quality of life (EQ-5D scale), healthcare resources, and caregiver burden (BAS scale) will be collected. Descriptive analysis with common statistics will be performed. DISCUSSION: This study will provide detailed descriptions of the management of BD in different countries, particularly in terms of clinical outcomes and resources used. Thus, it should provide psychiatrists with reliable and up-to-date information about those factors associated with different management patterns of BD. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01062607.

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The aim of the paper is to investigate the role played by differences in Institutional Quality on the process of technology catch-up across countries. Empirical evidence shows how countries endowed with better institutions are those experiencing higher TFP growth rates, faster rates of technology adoption and hence being those more rapidly closing the gap with the frontier. Conversely, countries lacking some minimum institutional level are shown to diverge in the long run and not to catch-up. Some institutions, however, play an ambiguous role in the creation and adoption of technology. We find that the tightening of Intellectual Property Rights reduces the ability of followers to freely imitate technology slowing down their catchup rate. This negative effect is stronger the farther the countriesare found from the frontier. Other institutional categories such as openness to trade, instead, benefit both leaders and followers.