Tasa Interna de Retorno Modificada en la valoración de proyectos: el caso de la Industria Petrolera

Proyecto de Graduación (Maestría en Administración de Empresas) Instituto Tecnológico de Costa Rica, Escuela de Administración de Empresas, 2016.Este proyecto consiste en diseñar e implementar un modelo que proporcione a los gerentes financieros o gerentes de proyectos una forma rápida y automatizada en el cálculo de la tasa interna de retorno modificada (TIRM) y la tasa interna de retorno (TIR clásico), con la finalidad de demostrar las debilidades del TIR, así como las ventajas de aplicar el TIRM en el sector petrolero internacional. Aplicando la tasa interna de retorno modificada (TIRM) en las valoraciones de los proyectos, se puede visualizar y mitigar el riesgo en caso de una caída fuerte en sus precios, como se observó a mediados del año 2014. Para lograr esto, se realizó una investigación sobre las variables y cálculos de cada método. También se analizó cautelosamente los estados financieros de la empresa norteamericana Exxon Mobil (símbolo de su acción en la bolsa de EEUU de XOM), para utilizar un ejemplo real de los distintos resultados al aplicar los métodos TIRM y TIR a un proyecto de extracción de petróleo. Aunque hay muchos estudios que se tienen que hacer antes de aprobar un proyecto de extracción de petróleo u otro plan de inversión, el TIR clásico es utilizado, hasta ahora, como un indicador clave, para aprobar el financiamiento del proyecto y demostrar su rentabilidad futura. La herramienta del (TIRM) no sólo es diseñada para el sector de petróleo, sino que también se va poder adaptar a cualquier tipo de proyecto, en sectores económicos dispersos y en diferentes países del mundo.Instituto Tecnológico de Costa Rica

Offshore drilling blowout risk model : an integration of basic causes, safety barriers, risk influencing factors and operational performance indicators

We would like to thank Witt O’Brien’s Brasil and Pemex Exploration and Production for partially sponsoring this work, and most of all: Adriano Ranieri, Greg Fenton, Flavio Andrade, Dr. Faustino Fuentes Nucamendi and Eduardo Zavala Nacer. Thanks also to Mr. Thiago Molina for providing his expertise on latest generation Deepwater MODU's, which enabled to add current and practical aspects to the academic research on kick detection and well control issues.Peer reviewedPostprin

Necrosis: Linking the Inflammasome to Inflammation

International audienceIn this issue of Cell Reports, Cullen et al. demonstrate that the release of mature interleukin-1β relies on necrotic plasma membrane permeabilization. Thus, caspases may have evolved to modulate the inflammatory potential of cell death, not to execute it

A novel method to prepare highly enriched primary cultures of chicken retinal horizontal cells

The retina is a heterogeneous tissue composed of different neuronal cells (photoreceptor (PRC), horizontal (HC), amacrine, bipolar and retinal ganglion RGC cells) and glial cells. Our aim in this work was to purify HCs from the chicken embryonic retina to obtain primary cultures highly enriched in these cells for further characterization. To this end, disaggregated retinas of chicken embryos at day 15 were subjected to a discontinuous bovine serum albumin (BSA) gradient of concentrations raging from 1 to 4%. After centrifugation, cells collected from the different phases were cultured for 4 days and characterized by immunochemistry and cell morphology. Phases were examined with specific antibodies against HC markers such as PROX-1, Islet-1 and calretinin, together with markers for other retinal cell populations. The results show that only in the fraction corresponding to 2.5% BSA did most of the cells display PROX-1 and Islet-1 positive immunoreactivities with a typical HC morphology. Moreover, Western blot assays indicate that the 2.5 % BSA phase exhibits the strongest PROX-1 immunolabeling, denoting the typical molecular weight (MW) of ~ 83KDa. Based on an accurate morphological analysis, a number of cells in this fraction resembled H1- and H3-type HCs (axon-bearing ?brush-shaped? and axon-less ?candelabrum-shaped? HCs respectively). In conclusion, the BSA gradient has so far proved to be a simple yet very useful method to selectively separate specific retinal cell types for the further study and characterization of their molecular, biochemical and electrophysiological properties.Fil: Morera, Luis Pedro. Universidad Empresarial Siglo XXI. Vicerrectorado de Innovación e Investigación. Instituto de Organizaciones Saludables; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Díaz, Nicolás Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Guido, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentin

Effective elastic thickness in the Central Andes. Correlation to orogenic deformation styles and lower crust high-gravity anomaly

Global studies have assessed the importance of elastic thickness (Te) on orogenic evolution, showing that the style and nature of upper crustal shortening are influenced by the inherited lithospheric strength. Thus, pioneer works have identified that the upper crustal deformation style in the easternmost sector of the Central Andes in South America are related to the elastic thickness (Te). There, the thick-skinned and pure-shear style of Santa Bárbara system was initially related to the existence of low Te values. In contrast, the thin-skinned and simple-shear style of deformation in the Subandean system involves high Te values. However, more recent Te studies in the Central Andes present conflicting results which lead to question this straightforward relation. Results from these studies show a strong dependence on the applied methodology hampering the general understanding of the lithospheric thermo-mechanical state of the Central Andes. To contribute to this issue, we perform a high-resolution Te map, using forward modeling by solving flexural equation of infinite plate model in two dimensions. To achieve this, the crust-mantle interface was calculated using a high-resolution gravity anomaly dataset which combines satellite and terrestrial data, and an average density contrast. Additionally, the gravity anomaly and the foreland basin depth in the Central Andes were best predicted by considering that lower crustal rocks fill the space deflected downward in the plate model. The obtained Te values show an inverse correlation with previous heat flow studies, and a strong spatial correlation with the styles and mechanisms of deformation in the easternmost sector of the Central Andes. In the Santa Bárbara system Te values less than 10 km predominate, whereas in the Subandean system high Te values were observed. Such high values correlate with the orogenic curvature and with an shallower gravity Moho zone, which breaks the regional trend of the Central Andes. This shallower gravity Moho is linked to a high-gravity anomaly located in the east part of the Eastern Cordillera and Subandean system. These results are also correlated with a high-velocity zone in the upper mantle previously found by receiver functions studies. This correlation could indicate changes in the properties of the lower crustal rocks that justify the shallower gravity Moho zone and explain in part the highest Te values.Fil: Garcia, Hector Pedro Antonio. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gianni, Guido Martin. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lupari, Marianela Nadia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sanchez, Marcos Ariel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Soler, Santiago Rubén. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ruiz, Francisco. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; ArgentinaFil: Lince Klinger, Federico Gustavo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto Geofísico Sismológico Volponi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Experimental cyclic behaviour of shear masonry walls reinforced with single and double layered Steel Reinforced Grout

Recent research on the mechanical characterisation of Steel Reinforced Grout (SRG) has highlighted its excellent performance as strengthening solutions for masonry structures. Using SRG with limited fabric density ensures a good textile-matrix interlocking, preventing at the same time the failure due to slippage or debonding from the substrate. This paper presents an experimental investigation on the use of SRG as in-plane strengthening solution for shear masonry walls composed of handmade solid clay brick and hydraulic lime mortar. Cyclic shear compression tests were carried out on walls strengthened with SRG comprising low density steel sheets (LDS). The SRG was applied on both faces of the walls with a strip configuration, using one and two layers of LDS. The experimental programme aimed to study the influence of the number of textile layers on the in-plane response of strengthened masonry walls in terms of failure mechanism, load-bearing capacity, energy dissipation, and ductility.The authors gratefully acknowledge the financial support from the Ministry of Economy and Competitiveness, Spain and from the Ministry of Science, Innovation and Universities of the Spanish Government, as well as that of the ERDF (European Regional Development Fund) through the project SEVERUS (Multilevel evaluation of seismic vulnerability and risk mitigation of masonry buildings in resilient historical urban centres, Ref. num. RTI2018-099589-B-I00). The reinforcement systems and construction of the specimens for the experimental programme have been funded by Kerakoll Spa through the RTD project “Seismic Strengthening of Masonry Walls” (Ref. num. A-01278). The authors wish to thank Paolo Casadei, José Luis Sanchez and José Dobón from Kerakoll Spa for their involvement and support. The support from Secretaria d’Universitats i Investigació de la Generalitat de Catalunya, Spain through a predoctoral grant awarded to the first author is also gratefully acknowledged.Peer ReviewedObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.1 - Desenvolupar infraestructures fiables, sostenibles, resilients i de qualitat, incloent infraestructures regionals i transfrontereres, per tal de donar suport al desenvolupament econòmic i al benestar humà, amb especial atenció a l’accés assequible i equitatiu per a totes les personesObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.4 - Redoblar els esforços per a protegir i salvaguardar el patrimoni cultural i natural del mónObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::13 - Acció per al Clima::13.1 - Enfortir la resiliència i la capacitat d’adaptació als riscos relacionats amb el clima i els desastres naturals a tots els païsosPostprint (author's final draft

Experimental and numerical insights on the in-plane behaviour of unreinforced and TRM/SRG retrofitted brick masonry walls by diagonal compression and shear-compression testing

The experimental determination of the parameters that characterise the in-plane shear behaviour of masonry structures is still a challenging task. Different authors have identified the key role of tensile strength in the definition of the in-plane shear behaviour of masonry, but unfortunately its direct experimental characterisation is not always feasible, and masonry’s tensile strength needs to be obtained from complex testing methodologies. As a result, tensile strength needs to be assessed from testing setups such as diagonal compression testing and shear compression testing when the failure mode of masonry is featured by tensile diagonal cracking. However, different formulations are available in the scientific literature regarding the interpretation of the experimental results derived from such tests. This work provides new insights on the interpretation of in-plane shear experimental behaviour of double-leaf historical clay brick masonry walls with low strength mortar joints, both unreinforced and retrofitted with textile reinforced mortar and steel reinforced grout. The research evaluates results derived from both testing methodologies, and investigates the potential correlation between them to fully characterise the in-plane shear behaviour of masonry walls. Finally, a numerical model is used to simulate each testing configuration and study the stress state at the centre of the walls to determine the tensile strength and its correlation with the shear strength and the maximum load attained.The authors gratefully acknowledge the financial support from the Ministry of Economy and Competitiveness and from the Ministry of Science, Innovation and Universities of the Spanish Government, as well as that of the ERDF (European Regional Development Fund) through the project SEVERUS (Multilevel evaluation of seismic vulnerability and risk mitigation of masonry buildings in resilient historical urban centres, Ref. num. RTI2018-099589-B-I00). The reinforcement systems and construction of the specimens for the experimental programme have been funded by Kerakoll Spa through the RTD project “Seismic Strengthening of Masonry Walls” (Ref. num. A-01278). The authors wish to thank José Luis Sanchez and José Dobón from Kerakoll Spa and Paolo Casadei, for their involvement and support. The support from Agència de Gestió d’Ajuts Universitaris i de Recerca de la Generalitat de Catalunya through a predoctoral grant awarded to the first author is also gratefully acknowledged.Peer ReviewedObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.4 - Redoblar els esforços per a protegir i salvaguardar el patrimoni cultural i natural del mónObjectius de Desenvolupament Sostenible::13 - Acció per al Clima::13.1 - Enfortir la resiliència i la capacitat d’adaptació als riscos relacionats amb el clima i els desastres naturals a tots els païsosObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.1 - Desenvolupar infraestructures fiables, sostenibles, resilients i de qualitat, incloent infraestructures regionals i transfrontereres, per tal de donar suport al desenvolupament econòmic i al benestar humà, amb especial atenció a l’accés assequible i equitatiu per a totes les personesPostprint (published version

Cyclic shear-compression testing of brick masonry walls repaired and retrofitted with basalt textile reinforced mortar

This paper reports an experimental programme on masonry walls composed of handmade solid clay brick and hydraulic lime mortar. Reversed cyclic shear compression tests were carried out on the walls in three different configurations: unreinforced, repaired and retrofitted, and just retrofitted. Damaged walls were repaired and retrofitted with Basalt Textile Reinforced Mortar (B TRM) and tested again to investigate the recovery of strength, stiffness and the improvement in drift capacity. The repair consisted in filling the open cracks and replacing the damaged bricks by following the so-called ‘‘scuci-cuci’’ technique. The just retrofitted configuration consisted of externally bonded B-TRM on undamaged walls. The B-TRM system comprised continuous bidirectional grids of basalt fibre embedded in hydraulic lime mortar on both surfaces of the walls. The experimental results showed the suitability of the proposed solutions for seismic retrofit and post-earthquake repair of existing masonry buildings. The research results highlighted the capacity of the proposed repair technique to reinforce damaged walls and the effectiveness of the investigated B-TRM system in increasing the resistance, the ductility, and the energy dissipation of unreinforced clay brick masonry. In addition, the results allowed a better understanding of the behaviour of masonry walls subjected to cyclic horizontal displacement in terms of failure mechanism and displacement capacities.The authors gratefully acknowledge the financial support from the Ministry of Economy and Competitiveness and from the Ministry of Science, Innovation and Universities of the Spanish Government, as well as that of the ERDF (European Regional Development Fund) through the project SEVERUS (Multilevel evaluation of seismic vulnerability and risk mitigation of masonry buildings in resilient historical urban centres, Ref. num. RTI2018-099589-B-I00). The reinforcement systems and construction of the specimens for the experimental programme have been funded by Kerakoll Spa through the RTD project “Seismic Strengthening of Masonry Walls” (Ref. num. A-01278). The authors wish to thank Paolo Casadei, José Luis Sanchez and José Dobón from Kerakoll Spa for their involvement and support. The support from Secretaria d’Universitats i Investigació de la Generalitat de Catalunya through a predoctoral grant awarded to the first author is also gratefully acknowledged.Peer ReviewedObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.1 - Desenvolupar infraestructures fiables, sostenibles, resilients i de qualitat, incloent infraestructures regionals i transfrontereres, per tal de donar suport al desenvolupament econòmic i al benestar humà, amb especial atenció a l’accés assequible i equitatiu per a totes les personesObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.4 - Redoblar els esforços per a protegir i salvaguardar el patrimoni cultural i natural del mónObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::13 - Acció per al Clima::13.1 - Enfortir la resiliència i la capacitat d’adaptació als riscos relacionats amb el clima i els desastres naturals a tots els païsosPostprint (published version