University of Patras

About: University of Patras is a education organization based out in Pátrai, Greece. It is known for research contribution in the topics: Population & Catalysis. The organization has 13372 authors who have published 31263 publications receiving 677159 citations. The organization is also known as: Panepistímio Patrón.

Destination Image Components and Word-of-Mouth Intentions in Urban Tourism A Multigroup Approach

Abstract: The purpose of this study was to explore differences among three distinct groups, namely local residents, past tourists, and prospective tourists, in their perceptions of cognitive, affective, and overall image of a city destination and their future behavior. Analysis of data generally confirmed previously established structural relationships of cognitive and affective image, overall destination image, and word-of-mouth intentions. However, differences were identified among the three groups in terms of their destination image perceptions and their behavioral intentions to engage in word-of-mouth communications. Specifically, residents who engaged in word-of-mouth were primarily influenced by the cognitive and affective destination image components, while tourists relied on overall image perceptions.

Calibration of the Specific Barrier Model to Earthquakes of Different Tectonic Regions

Abstract: The specific barrier model, proposed and developed by Papageorgiou and Aki (1983a,b; 1985) provides the most complete, yet parsimonious, self-consis- tent description of the faulting process. It applies both in the "near-fault" and in the "far-field" region, thus allowing for consistent ground-motion simulations over the entire frequency range and for all distances of engineering interest. The model has been implemented in the stochastic method and calibrated with extended databases of response spectral amplitudes from earthquakes of intraplate regions (mainly east- ern North America events), interplate regions, and regions of tectonic extension (Spu- dich et al., 1999, database). The ensemble average value of a key parameter of the specific barrier model, the local stress drop Dr L ,i s� 161 bars for interplate earth- quakes, � 114 bars for extensional regime earthquakes, and � 180 bars for intraplate earthquakes. The high-frequency source spectral levels of interplate and extensional regime earthquakes deviate significantly from self-similar scaling. The deviation is most likely caused by the "effective" source area and/or irregularities in the rupture kinematics. We account for their overall effects through a high-frequency source complexity factor, f, in the source spectrum of the specific barrier model. As a result, inter- and intraplate source spectra show similar high-frequency levels at moderate magnitudes but intraplate earthquakes have higher spectral levels at the larger mag- nitudes. The interplate soil residuals show clear signs of nonlinear site response, whereas only slight signs of such nonlinearity are observed for the extensional data- set. The regional models calibrated in this study are in reasonably good agreement with other regional attenuation relationships and provide a reliable and physically realistic, yet computationally efficient, way to model strong ground motions with implications for seismic hazard and risk analysis. Online material: Strong-motion station and event-station pair information.

Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

Abstract: During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB), hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved.

Engineering Ground-Motion Parameters Attenuation Relationships for Greece

Abstract: Engineering ground-motion parameters can be used to describe the dam- age potential of an earthquake. Some of them correlate well with several commonly used demand measures of structural performance, liquefaction, and seismic-slope stability. The importance of these parameters comes from the necessity of an alter- native measure to the earthquake intensity. In the proposed new attenuation relation- ship we consider peak values of strong motion, spectral acceleration, elastic input energy at selected frequencies, root-mean-square acceleration, Arias intensity, char- acteristic intensity, Fajfar index, cumulative absolute velocity, cumulative absolute velocity integrated with a 5 cm/sec 2 lower threshold, and spectrum-intensity energy. This article describes the steps involved in the development of new attenuation re- lationships for all the preceding parameters, using all existing, up-to-date Greek strong-motion data. The functional form of the empirical equation is selected based on a theoretical model, and the coefficients of the independent variables are deter- mined by employing mixed effects regression analysis methodologies.