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Puerto Colombia, Colombia

The Universidad del Norte is the main academic center for higher education in northern Colombia. It was founded in 1966 by a group of businessmen led by Karl C. Parrish in the city of Barranquilla. It started its academic operation on July 11, 1966, with 58 students and 10 teachers on core courses of business administration and engineering.According to a recent ranking of the best universities of Colombia the "Universidad del Norte" is one of the 5 best ones of Colombia.The university is composed of 8 academic divisions: Engineering, Administrative science, Humanities and Social science, Health science, Legal science and the Basic science division, as well as the Institute of Superior Studies in Education.The university offers careers in industrial, mechanical, computer, civil, electrical and electronic engineering, as well as Medicine, Business Administration, Law, Psychology, International Relations, International Business, Math, Industrial Design, Graphic Design, Architecture, and several other faculties. In total, the university offers 22 undergraduate programs, 69 professional specialization programs, 37 Master's programs, and 6 doctoral programs. The University also offers some specialization programs in Santa Marta. All of the engineering programs were accredited by the ABET, which is one of the most important international accreditation agencies, located in Baltimore, United States.It is one of the most important cultural and technological centers on the Caribbean region of Colombia. Wikipedia.

Guzman J.D.,Universidad del Norte, Colombia
Molecules | Year: 2014

Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC) of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Ortiz Royero J.C.,Universidad del Norte, Colombia
Natural Hazards | Year: 2012

An analysis of the exposure of the Colombian Caribbean coast to the effect of tropical storms and hurricanes was conducted using historical records from between 1900 and 2010. The Colombian Caribbean coast is approximately 1,760 km long, and the main coastal cities in this important region are Riohacha (RIO), Santa Marta (STA), Barranquilla (BAQ), and Cartagena (CTG). The surface extension of the Colombian Caribbean is almost 590,000 km 2. The cumulative number of events was used to determine the exposure and to identify the most vulnerable zones on the continental coast of Colombia and in the country's insular Caribbean. Although the Colombian Caribbean coast is not registered as a potentially vulnerable zone in international databases, there have been significant events in the region, some of which even hit land. The results show that the island of San Andrés (SA) and the Department of Guajira are the zones most likely to be affected by storms in the Colombian Caribbean. Hurricane Joan in October of 1988 has been the most devastating event in the history of hurricanes in Colombian waters. © 2011 Springer Science+Business Media B.V.

Alonso E.E.,Polytechnic University of Catalonia | Berdugo I.R.,Universidad del Norte, Colombia | Ramon A.,Polytechnic University of Catalonia
Geotechnique | Year: 2013

The paper describes the expansive phenomena affecting Lilla tunnel in Spain during construction and subsequent operation. The geology of the site and the performance of alternative support designs are described. Field observations are analysed to identify the causes of the observed swelling. It was found that long-term swelling in Lilla tunnel was the result of gypsum crystal growth in discontinuities. The phenomenon was a consequence of a few contributing factors: significant presence of anhydrite, existent or activated discontinuities, and the circulation of water. These conditions were present in the highly tectonised Tertiary claystone in Lilla. The original horseshoe cross-section was transformed into a circular one, and a reinforced concrete lining was built to resist swelling pressures. Long-term monitoring of the reinforced tunnel provided valuable data on the evolution of swelling pressures against the lining, and on the stresses developed in the resisting structure. The highly heterogeneous distribution of swelling pressures against the lining explains the low strains measured in reinforcement bars despite the very high maximum swelling pressures recorded.

Hernandez R.J.,Universidad del Norte, Colombia | Fahrenthold E.P.,University of Texas at Austin
International Journal for Numerical Methods in Engineering | Year: 2013

Hamiltonian models of high-velocity impact dynamics, based on a hybrid particle-element kinematic scheme, offer an energy conserving description of general contact-impact, perforation, and fragmentation physics with applications in a number of important engineering fields. Published work on these models has considered only a uniform finite element mesh, requiring curved surfaces and many target and projectile geometries to be represented in an approximate fashion. In recent research, the authors have developed a new formulation suitable for application to any solid model described by an unstructured hexahedral mesh. The formulation incorporates a new algorithm, which constructs an ellipsoidal particle discretization of the mass distribution described by a general hex mesh and a new density interpolation suitable for use with general ellipsoidal arrays whose particles vary in mass, shape, and spatial orientation. Application of the method in the simulation of high-velocity impact problems shows good agreement with experiment, for both smoothly graded and deliberately distorted hexahedral meshes. © 2013 John Wiley & Sons, Ltd.

Reuter M.,University of Mainz | Tuiran E.,Universidad del Norte, Colombia
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the "dressing" of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity. © 2011 American Physical Society.

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