(1953 - )
Autor principal de la vacuna de antígeno sintético contra el Haemöphilus influenzae tipo b (Hib), causante de la mitad de las infecciones bacterianas que padecen los niños menores de cinco años.
Technical Sciences
2000 | “Environmental influence on the pathology of Monuments of high historical value built with natural stone materials ".
Main author: Lucrecia Pérez Echazabal.

The author has concentrated in this work long years dedicated to a field, where she has obtained national and international recognition. The developed topic is about the influence of environmental factors on the pathologies of buildings of patrimonial value, mainly those made of stone. Coincidently, these are generally the oldest and most monumentally valuable buildings in Cuba, and also in the rest of the region with the same climate and the same cultural antecedents of Spanish colonization. In this subject there have, generally, been followed rehabilitating intervention procedures imported from other contexts, mainly European, without an appropriate reelaboration; while many of the used techniques were empirically applied, without a correct scientific sustentation.

In this work, it is developed an analysis procedure that allows achieving a systematized knowledge on the several factors that interact on stone buildings' deterioration, from the origin and composition of the rock used, to the action of wind and water, temperature changes, biological agents and modifications introduced by human action. One of the case studies is that of La Cabaña fortress (the largest colonial fortress in the New World).

It is carried out an environmental analysis in the historical center of Havana, and it was possible to identify different environmental units, coming to the partial conclusions that the atmospheric contamination effect on the stone heritage cannot only be limited to municipal or even to city scale, but also that it is necessary going through the different scales, until we arrive to the quality of the air nearest to the monument, in other words, covering from the territory to the object. In this case, this work became more difficult because there is not a systematic control on the polluting agents or on their effects on the built heritage.

It is carried out a field and statistical study on the morphology of deterioration, detecting the correlation between abrupt and periodic changes of environmental conditions with a deeper and quicker stone modification; and the origin and chemical composition of the rock where it was extracted; and its structure, texture and environmental conditions intervene in this. Four alteration groups are studied: superficial modifications (patinas and layers of different types), material loss (disintegration, erosion, alveolization and material losses in joints), ruptures, disjunctions and anthropic modifications, and those produced by plants and animals.

It was carried out a casuistical analysis to determine the link among alterations and environment, conceived as a system. That study was made by facades, determining the influence on the deterioration of orientation, sunning, wind direction and its complex redistribution in the compact urban plot, facade's form and geometry, and interventions modifying the original condition, which is something that had not been done before.

In short, this work is up-to-date and it is specially useful in the programs of conservation and recovery of stone heritage in Havana -where it is being already applied- Santiago and other Cuban cities; and this interest is spreading to other countries from the Caribbean and Central America with similar climatic conditions and heritage.