Santiago Lopez | Facultad de Ingenieria (original) (raw)

Papers by Santiago Lopez

The detailed study of the deterioration suffered by the materials of the components of a nuclear ... more The detailed study of the deterioration suffered by the materials of the components of a nuclear facility, in particular those forming part of the reactor core, is a topic of great interest which importance derives in large technological and economic implications. Since changes in the atomic-structural properties of relevant components pose a risk to the smooth operation with clear consequences for security and life of the plant, controlling these factors is essential in any development of engineering design and implementation. In recent times, tungsten has been proposed as a structural material based on its good resistance to radiation, but still needs to be done an extensive study on the influence of temperature on the behavior of this material under radiation damage. This work aims to contribute in this regard. Molecular Dynamics (MD) simulations were carried out to determine the influence of temperature fluctuations on radiation damage production and evolution in Tungsten. We ha...

Remote Sensing, 2021

Estimating variations in material properties over space and time is essential for the purposes of... more Estimating variations in material properties over space and time is essential for the purposes of structural health monitoring (SHM), mandated inspection, and insurance of civil infrastructure. Properties such as compressive strength evolve over time and are reflective of the overall condition of the aging infrastructure. Concrete structures pose an additional challenge due to the inherent spatial variability of material properties over large length scales. In recent years, nondestructive approaches such as rebound hammer and ultrasonic velocity have been used to determine the in situ material properties of concrete with a focus on the compressive strength. However, these methods require personnel expertise, careful data collection, and high investment. This paper presents a novel approach using ground penetrating radar (GPR) to estimate the variability of in situ material properties over time and space for assessment of concrete bridges. The results show that attributes (or feature...

Urología Colombiana, 2017

Tiempos Medicos Revista De Educacion Medica Continuada, 2003

Las enfermedades inflamatorias cronicas intestinales (EICI) son un grupo de entidades clinicopato... more Las enfermedades inflamatorias cronicas intestinales (EICI) son un grupo de entidades clinicopatologicas de etiologia desconocida, con una incidencia significativa y una prevalencia cada vez mas alta en nuestra poblacion. Las dos enfermedades mas importantes son la Colitis Ulcerosa (CU) y la Enfermedad de Crohn (EC). Su repercusion clinica y economica se multiplica al afectar a personas jovenes en la plenitud de actividad familiar y social. El diagnostico resulta esencial en estas entidades en una doble faceta. No solo es importante que el proceso diagnostico inicial sea rapido y exacto, sino que es fundamental disponer a lo largo de su evolucion en el tiempo de procedimientos que nos permitan conocer la "actividad"/ concepto a veces de dificil definicion, pero trascendente a la hora de disenar la estrategia terapeutica en cada momento.

Proceedings of 7th International Conference on Inertial Fusion Sciences and Applications Ifsa 2011 7th International Conference on Inertial Fusion Sciences and Applications Ifsa 2011 12 09 2011 16 09 2011 Bordeaux Francia, 2011

International journal of sports physiology and performance, Jan 22, 2015

This study aimed to explore the cardiovascular and metabolic responses of 9 Optimist sailors (12.... more This study aimed to explore the cardiovascular and metabolic responses of 9 Optimist sailors (12.7 yy ± 0.8; 153 cm ± 9; 41 kg ± 6; sailing career: 6.2 yy±1, peak oxygen uptake (VO2peak): 50.5 mL min-1 kg-1 ± 4.5) during on-water upwind sailing with various wind intensities (W). In a laboratory session, we measured VO2peak, Qpeak, MAPpeak and fHpeak using a progressive cycle ramp protocol. Steady state VO2, Q, MAP and fH at 4 submaximal workloads were also determined. During two on-water upwind sailing tests (constant course and with tacks), W,Q, MAP and fH were measured for 15 minutes. VO2 on-water was estimated on the basis of steady state fH measured on water and of the individual ΔVO2/ΔfH relationship obtained in the laboratory. VO2, fH and Q expressed as per cent of the corresponding peak values were linearly related with W; exercise intensity during on-water sailing corresponded to 46-48 % of VO2peak. MAP and total vascular peripheral resistance (TPR=MAP/Q) were larger (P <...

Revista de Gastroenterología de México, 2012

Introducción En la llevada a cabo en San Diego en el 2012 se presentaron varios trabajos relacion... more Introducción En la llevada a cabo en San Diego en el 2012 se presentaron varios trabajos relacionados con el los cuales se mencionan a continuación:

Science Translational Medicine, 2013

A T cell subset that emerges in blood after seasonal influenza vaccinations correlates with the d... more A T cell subset that emerges in blood after seasonal influenza vaccinations correlates with the development of protective antibody responses.

Journal of the American Medical Directors Association, 2013

Journal of Infectious Diseases, 2014

Background. Live attenuated influenza vaccine (LAIV) and trivalent inactivated influenza vaccine ... more Background. Live attenuated influenza vaccine (LAIV) and trivalent inactivated influenza vaccine (TIV) are effective for prevention of influenza virus infection in children, but the mechanisms associated with protection are not well defined. Methods. We analyzed the differences in B-cell responses and transcriptional profiles in children aged 6 months to 14 years immunized with these 2 vaccines. Results. LAIV elicited a significant increase in naive, memory, and transitional B cells on day 30 after vaccination, whereas TIV elicited an increased number of plasmablasts on day 7. Antibody titers against the 3 vaccine strains (H1N1, H3N2, and B) were significantly higher in the TIV group and correlated with number of antibody-secreting cells. Both vaccines induced overexpression of interferon (IFN)-signaling genes but with different kinetics. TIV induced expression of IFN genes on day 1 after vaccination in all age groups, and LAIV induced expression of IFN genes on day 7 after vaccination but only in children <5 years old. IFN-related genes overexpressed in both vaccinated groups correlated with H3N2 antibody titers. Conclusions. These results suggest that LAIV and TIV induced significantly different B-cell responses in vaccinated children. Early induction of IFN appears to be important for development of antibody responses.

Journal of Infectious Diseases, 2012

Background. Most patients with respiratory syncytial virus (RSV) bronchiolitis requiring admissio... more Background. Most patients with respiratory syncytial virus (RSV) bronchiolitis requiring admission to the pediatric intensive care unit (PICU) have no risk factors for severe disease. We sought to investigate the relationship between serum cytokine concentrations, innate immune responsiveness, and RSV disease severity. Methods. Previously healthy infants (median age, 2.6 months) with RSV bronchiolitis (PICU, n = 20; floor, n = 46) and healthy matched controls (n = 14) were enrolled, and blood samples were obtained within 24 hours of admission to measure plasma tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), interleukin 8 (IL-8), and interleukin 10 (IL-10) concentrations and, whole blood lipopolysaccharide-stimulated cytokine production capacity. Results. Plasma IL-6, IL-8, and IL-10 concentrations were comparable between PICU and floor patients, but higher than in healthy controls (P < .05). In contrast, TNF-α, IL-6, and IL-8 production capacity was significantly decreased in PICU compared with both floor patients and healthy controls. In adjusted analyses, only impaired TNF-α and IL-8 production capacity were associated with longer length of stay (P = .035) and greater disease severity scores (P = .001). Conclusions. Infants with severe RSV bronchiolitis had increased plasma cytokine concentrations and yet impaired innate immunity cytokine production capacity, which predicted worse disease outcomes. Immune monitoring of otherwise healthy infants with RSV lower respiratory tract infection could help identify patients at risk for severe disease at the time of hospitalization.

Frontiers in Neuroscience, 2009

Business History Review, 2005

Reviewed by Stanley L. Engerman Adam Smith's concept of the division of labor is most frequently ... more Reviewed by Stanley L. Engerman Adam Smith's concept of the division of labor is most frequently applied to the production of goods. Yet it can also be applied to the intellectual world, indicating the differing roles played by scholars in contributing to the production of knowledge. In this regard, Douglass C. North, corecipient of the 1993 Nobel Prize in Economic Sciences, has played a unique role in the fields of economic history and institutional economics. North has specialized in broadening the types of questions to be asked in studying economic development, opening up new perspectives for others to deal with. North wrote extensively on the role of institutions in influencing economic growth, extending the analysis of economic factors beyond the traditional three or four productive factors to include the evolution of the rules of economic society that direct or constrain economic behavior. The recognition of the importance of privateproperty rights, and of creditable commitment, for example, emerged from the work of North and those following the lines he discussed. In Understanding the Process of Economic Change, North extends further the range of questions he sees as essential to the study of economic change. The questions now include the thought processes of individuals: how people learn to define the institutions that influence behavior, and how they deal with change and the need to adapt to changing conditions. The analysis of such questions draws upon disciplines not usually considered central to economists, cognitive science and psychology, disciplines concerned with how people think, learn, and change views. It is the discussion of the significance of cognitive science for the study of economic policy and for the understanding of how to help generate economic growth in the present-day world that North regards as the central contribution of the volume. The present volume, one in the series entitled the Princeton Economic History of the Western World, comprises thirteen chapters in two parts. The first, "The Issues Involved in Understanding Economic Change," deals with human thought processes and belief systems. The basic starting point is that "the key to improving economic performance, is the deliberate effort of human beings to control their environment" (p. 1). The chapters in this part deal with problems of accurate understanding, including risk, imperfect perceptions, the nature of culture and religion, and the existing political structure. The limits of neoclas

Analytical Biochemistry, 2008

We report nucleic acid (NA) adsorption isotherms and elution profiles for silica surfaces and use... more We report nucleic acid (NA) adsorption isotherms and elution profiles for silica surfaces and use these to design a miniaturized NA purification unit based on solid-phase extraction with silica beads. The procedure is based on a pressure drop equation for flow through a packed bed and allows estimation of key design parameters such as channel dimensions, liquid flow rates, sample volume, and amount of silica needed. The usefulness of this design procedure is demonstrated by applying it to a column-based NA purification device for influenza detection for a case study of Madin-Darby canine kidney cells infected with influenza A virus.

Regulatory Peptides, 1991