170 research outputs found
Study of the fracture process of Al Hoceima earthquake (24/02/2004, Mw=6.2) from regional and teleseismic data.
We studied the source time function (STF) and rupture process of the 2004 Alhoceima, Morocco earthquake of Mw = 6.2 using teleseismic and regional broad-band data. From regional broad-band data, STF function was determined using three large after- shocks as empirical Green functions. We inverted of body wave forms at teleseismic distances using an extended source model with rupture velocity between 2.5-3.0 km and using as preliminary orientation the fault plane solution derived from 126 P-wave polarities. Results show a complex bilateral rupture formed by four shallow subevents (2-8 km) with a maximum seismic moment release during the first seconds (more than 80% of a total of 1.8x1018 Nm) and time duration of 8-10 s. The focal mechanism shows a strike slip motion with a normal component. Nodal planes strike on NNE- SSW and WNW-ESE direction with horizontal pressure axes in NNW-SSE direction. The rupture propagated mainly towards the North. This propagation is in agreement with the damages caused in the epicentral region. The larger aftershocks have been relocated using a master event method. Comparisson of these results with those ob- tained for the 1994 earthquake shown similar behaviour: complex rupture process and, apparently, no relation of the 1994 nor the 2004 shocks with the Nekor fault, the most important geological feature in the area. The stress pattern derived from focal mech- anisms of 1994 and 2004 are in agreement with the regional stress pattern, horizontal compression in NNW-SSE and horizontal extension in E-W direction in the Alboran Sea
Intermediate depth and deep earthquakes: complexity of the Ibero-Magrhebian region
The Ibero-Magrhebian region is located at the plate boundary between Eurasia and Africa and it is a tectonically complex region. A sign of the complexity, is the occurrence of intermediate depth earthquakes (40<h<150 km), located in south Spain, between Granada- Malaga and at the west part of Alboran Sea, together with the occurrence of very deep earthquakes (h≈650 km) near Dúrcal (Granada). Intermediate depth shocks are mostly confined within a relatively narrow region (50 km width) located East of Gibraltar, extending NNE-SSW from the Malaga (Spain) area to a region offshore the Moroccan coast. We have studied focal mechanisms of these earthquakes from inversion of body wave. The stress pattern in the Ibero-Maghrebian region obtained from solutions of selected shallow, intermediate depth and deep shocks show the complexity of the region. The seismotectonic scheme show horizontal compression in NNW-SSE direction in the Gulf of Cádiz. In northern Africa, the stress pattern changes and it corresponds to strike-slip motion, with extends from west of the Gibraltar Strait until the western Algeria, where in the Oran region the horizontal compression N-S reapers, with a clear domain of the thrusting faults in Algeria. In the Alboran Sea there is horizontal extension in E-W direction for shallow events. The intermediate depth shock located at the western part of the Alboran Sea show a change on the stress pattern: to the west of 4.5oW, focal mechanisms show vertical tension axis, while to the east, they show vertical pressure axis. These stress orientations are not present in deep earthquakes, where the pressure axes dip 45o to the east. The intermediate and deep earthquakes may be related to some kind of subduction or delamination processes, more recent for the intermediate depth shocks and older for the very deep activity
Developing an agro-climatic zoning model to determine potential growing areas for Camelina sativa in Argentina
The purpose of this paper was the development of an agro-climatic zoning model to determine potential growing areas for Camelina sativa in Argentina. Camelina (Camelina sativa L.) is a promising and sustainable alternative energy crop that belongs to the Brassicaceae (mustard) family. Camelina sativa oil contains around 40% fatty acids, of which only a small percentage are saturated. Camelina sativa derived biokerosene used in aviation has shown 84% reduction in greenhouse gas emissions during its life cycle, compared to petroleum kerosene. It has the potential of becoming the renewable fuel of choice for air navigation in the future. Agro-climatology is a valuable tool in the identification of agro-climates with favorable conditions for the introduction of new crops. Agro-climatic zoning permits identifying areas with different potential yields, as per their environmental conditions. It was necessary to evaluate the requirements, limits and bio-meteorological tolerance and conditions for these species, taking into account the climatological characteristics of native areas and regions for their successful cultivation around the world. In order to define this crop's agroclimatic aptitude in Argentina, climatic data was analyzed from meteorological stations, corresponding to the period 1981-2010. Finally, Camelina's potential growing areas were obtained with 5 differentiated suitability classes. Based on international bibliography, the authors outlined an agro-climatic zoning model to determine potential growing areas in Argentina for Camelina sativa. This model may be applied to any part of the world, using the agroclimatic limits presented in this paper. This is an innovative work, made by the implementation of a Geographic Information System that can be updated by the further incorporation of complementary information, with the consequent improvement of the original database.Fil: Falasca, Silvia Liliana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miranda del Fresno, Ma. Carolina. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; ArgentinaFil: Waldman, C.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentin
Reconstrucción tomográfica tridimensional a partir de radiografías
El presente trabajo estudia la factibilidad de realizar reconstrucciones tomográficas axiales a partir de placas radiográficas convencionales. Se plantea un procedimiento posible para realizar esta reconstrucción, detectando en cada radiografía el eje de giro y el encuadrado en forma automática. Estas ideas se las aplicó al caso de un conector BNC del que se obtuvieron ocho radiografías utilizando un dispositivo de Plasma Focus, mostrando así la factibilidad del procedimiento. A continuación se analiza la sensibilidad de la calidad de imagen a errores tanto en la detección del eje de rotación y encuadrado de las proyecciones como a la corrección por la diferencia de intensidades entre las diferentes radiografías. Finalmente se discuten las potencialidades de esta técnica y las posibles mejoras a introducir en la mismaÁrea: Procesamiento de Imágenes - Tratamiento de Señales - Computación Gráfica - VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI
Reconstrucción tomográfica tridimensional a partir de radiografías
El presente trabajo estudia la factibilidad de realizar reconstrucciones tomográficas axiales a partir de placas radiográficas convencionales. Se plantea un procedimiento posible para realizar esta reconstrucción, detectando en cada radiografía el eje de giro y el encuadrado en forma automática. Estas ideas se las aplicó al caso de un conector BNC del que se obtuvieron ocho radiografías utilizando un dispositivo de Plasma Focus, mostrando así la factibilidad del procedimiento. A continuación se analiza la sensibilidad de la calidad de imagen a errores tanto en la detección del eje de rotación y encuadrado de las proyecciones como a la corrección por la diferencia de intensidades entre las diferentes radiografías. Finalmente se discuten las potencialidades de esta técnica y las posibles mejoras a introducir en la mismaÁrea: Procesamiento de Imágenes - Tratamiento de Señales - Computación Gráfica - VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI
Reconstrucción tomográfica tridimensional a partir de radiografías
El presente trabajo estudia la factibilidad de realizar reconstrucciones tomográficas axiales a partir de placas radiográficas convencionales. Se plantea un procedimiento posible para realizar esta reconstrucción, detectando en cada radiografía el eje de giro y el encuadrado en forma automática. Estas ideas se las aplicó al caso de un conector BNC del que se obtuvieron ocho radiografías utilizando un dispositivo de Plasma Focus, mostrando así la factibilidad del procedimiento. A continuación se analiza la sensibilidad de la calidad de imagen a errores tanto en la detección del eje de rotación y encuadrado de las proyecciones como a la corrección por la diferencia de intensidades entre las diferentes radiografías. Finalmente se discuten las potencialidades de esta técnica y las posibles mejoras a introducir en la mismaÁrea: Procesamiento de Imágenes - Tratamiento de Señales - Computación Gráfica - VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI
Improvement of a System for Catchment, Pretreatment and Treatment of Runoff Water Using PIV Tests and Numerical Simulation
This paper studies how to improve the efficiency of a new system for catchment, pretreatment, and treatment of runoff water (SCPT). This system is integrated into an urban sustainable gravity settler that can decrease diffusive pollution. This study provides important advantages for the ecosystem by improving new sustainable drainage to clean runoff water. In this paper, an investigation methodology known as hybrid engineering (HE) was used. HE combines experimental tests and numerical simulations, both of them conducted on a 1:4-scale prototype. In this study, numerical simulations by the finite-volume method (FVM) and experimental tests by particle image velocimetry (PIV) were compared. A strong correlation between the numerical and experimental analysis was found. Next, the efficiency of the SCPTwas optimized by design of experiments (DOE). Analysis of experimental and numerical results and their comparison are presented in this paper.The authors wish to express their gratitude to the Spanish Ministry of Economy and Competitiveness for the research project BIA2009-08272 funding
Translocated LPS Might Cause Endotoxin Tolerance in Circulating Monocytes of Cystic Fibrosis Patients
Cystic Fibrosis (CF) is an inherited pleiotropic disease that results from abnormalities in the gene codes of a chloride channel. The lungs of CF patients are chronically infected by several pathogens but bacteraemia have rarely been reported in this pathology. Besides that, circulating monocytes in CF patients exhibit a patent Endotoxin Tolerance (ET) state since they show a significant reduction of the inflammatory response to bacterial stimulus. Despite a previous description of this phenomenon, the direct cause of ET in CF patients remains unknown. In this study we have researched the possible role of microbial/endotoxin translocation from a localized infection to the bloodstream as a potential cause of ET induction in CF patients. Plasma analysis of fourteen CF patients revealed high levels of LPS compared to healthy volunteers and patients who suffer from Chronic Obstructive Pulmonary Disease. Experiments in vitro showed that endotoxin concentrations found in plasma of CF patients were enough to induce an ET phenotype in monocytes from healthy controls. In agreement with clinical data, we failed to detect bacterial DNA in CF plasma. Our results suggest that soluble endotoxin present in bloodstream of CF patients causes endotoxin tolerance in their circulating monocytes
Novel intravesical bacterial immunotherapy induces rejection of BCG-unresponsive established bladder tumors
Background Intravesical BCG is the gold-standard therapy for non-muscle invasive bladder cancer (NMIBC); however, it still fails in a significant proportion of patients, so improved treatment options are urgently needed. Methods Here, we compared BCG antitumoral efficacy with another live attenuated mycobacteria, MTBVAC, in an orthotopic mouse model of bladder cancer (BC). We aimed to identify both bacterial and host immunological factors to understand the antitumoral mechanisms behind effective bacterial immunotherapy for BC. Results We found that the expression of the BCG-absent proteins ESAT6/CFP10 by MTBVAC was determinant in mediating bladder colonization by the bacteria, which correlated with augmented antitumoral efficacy. We further analyzed the mechanism of action of bacterial immunotherapy and found that it critically relied on the adaptive cytotoxic response. MTBVAC enhanced both tumor antigen-specific CD4 + and CD8 + T-cell responses, in a process dependent on stimulation of type 1 conventional dendritic cells. Importantly, improved intravesical bacterial immunotherapy using MBTVAC induced eradication of fully established bladder tumors, both as a monotherapy and specially in combination with the immune checkpoint inhibitor antiprogrammed cell death ligand 1 (anti PD-L1). Conclusion These results contribute to the understanding of the mechanisms behind successful bacterial immunotherapy against BC and characterize a novel therapeutic approach for BCG-unresponsive NMIBC cases. © Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ
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