Adverse effects arising from conservation treatments on archaeological sites: theory, practice and review

Conservation and restoration of archaeological sites developed significantly in the second half of the twentieth century, with greater emphasis in recent decades, which has led to a considerable number of interventions. Methodology of intervention has changed significantly since more interventionist measures are performed against the current criteria of minimum intervention, although what actually occurs today is a difficult balance between innovation (experimental application of new techniques and products) and minimum intervention. The debate, in the case of archaeological sites, has focused on the actions traditionally more aggressive: cleaning, consolidation or reintegration, as this is where most notable has been the restorative action throughout history. The restoration, like everything else, has been subject of trends, in relation to the appearance of new products and technologies, and today remains a discipline that widely develops experimental practice. It certainly brings great benefits and constant renewal of criteria and methodologies, but also risks by introducing new compounds that may interact negatively with original substrate, although their effects cannot be checked in the short or medium term. The lack of knowledge of the causes of decay arising from previous interventions has generated a series of continuous protection and consolidation treatments at different periods. Restorers currently must deal with decayed areas where the products, methodology or techniques used, have caused a negative effect on the original material. This paper attempts to explore the general study of effects and alterations arising from restoration treatments, as well as reviewing of scientific publications related to this issue.series of continuous protection and consolidation treatments at different periods. Restorers currently must deal with decayed areas where the products, methodology or techniques used, have caused a negative effect on the original material. This paper attempts to explore the general study of effects and alterations arising from restoration treatments, as well as reviewing of scientific publications related to this issue.This research was supported by the PICATA fellowship program from Campus of International Excellence of Moncloa. Our acknowledgements to GEOMATERIALES programme (S2009-MAT1629/GEOMATERIALES) within Instituto de Geociencias (CSIC, UCM), to AIPA programme (ETSAM, Polytechnic University of Madrid) and to the Research Group financed by the Complutense University of Madrid "Alteration and Conservation of heritage stone materials” (ref. 921349).Peer reviewe

Effects of conservation interventions on the archaeological Roman site of Merida (Spain). Advance of research

Research on the assessment of the effects of conservation/restoration treatments on stone material has been significant in recent years, with focus on the early observation of decay caused by the application of these treatments. However, in the case of archaeological sites, research is still scarce and few studies on the subject have been published. Restoration, as everything else, has changed according to trends, mainly guided by the release of new products and technologies, an experimental field where scientific assessment of suitability, efficacy and durability pre-evaluations of treatments are not always conducted. Some efforts have been made to solve this problem in the architectural field, where functional needs and technical requirements force to set clear standards. Unfortunately, archaeological sites, unlike historic buildings, have specific features that preclude the extrapolation of these results. A critical review of the methodologies, products and restoration materials is necessary, coupled with deeper research on degradation mechanisms caused by these treatments in the mid- and long-term. The aim of this paper is to introduce the research on the above issues using Merida as a case study.Peer Reviewe

Selenides and Diselenides: A Review of Their Anticancer and Chemopreventive Activity

Selenium and selenocompounds have attracted the attention and the efforts of scientists worldwide due to their promising potential applications in cancer prevention and/or treatment. Different organic selenocompounds, with diverse functional groups that contain selenium, have been reported to exhibit anticancer and/or chemopreventive activity. Among them, selenocyanates, selenoureas, selenoesters, selenium-containing heterocycles, selenium nanoparticles, selenides and diselenides have been considered in the search for efficiency in prevention and treatment of cancer and other related diseases. In this review, we focus our attention on the potential applications of selenides and diselenides in cancer prevention and treatment that have been reported so far. The around 80 selenides and diselenides selected herein as representative compounds include promising antioxidant, prooxidant, redox-modulating, chemopreventive, anticancer, cytotoxic and radioprotective compounds, among other activities. The aim of this work is to highlight the possibilities that these novel organic selenocompounds can offer in an effort to contribute to inspire medicinal chemists in their search of new promising derivatives

Effects of Conservation Interventions on the Archaeological Roman Site of Merida (Spain). Advance of Research

Efectos derivados de tratamientos de conservación y restauración sobre material inorgánico en yacimientos arqueológicos. Caso de estudio: Mérida

Non-destructive testing for the assessment of granite decay in heritage structures compared to quarry stone

Several types of granite found in two architectural heritage monuments were assessed with two non-destructive, portable techniques: Schmidt hammer rebound and ultrasound velocity (Vp). Similar assessments were conducted on the rock from which the granite was originally quarried for comparison. The results obtained, which revealed the existence of a direct correlation, constitute a useful indication of decay, particularly if the approximate dates of construction are known. And conversely, if they are not, such stone assessments may provide a rough estimate of when the structure was built. Both of these convenient, portable and non-destructive techniques may be used as reliable indicators of the degree of stone decay

Portelli, Alessandro (2020). <i>Lluvia y veneno. Bob Dylan y una balada entre la tradición y la modernidad</i> : Buenos Aires: Prometeo, 180 pp.

Portelli construye, a través de una biografía, un recorrido apasionante por la historia americana y mundial del último “largo” medio siglo. Recorre casi la totalidad de los grandes problemas de la historia oral, y evidencia, sin buscarlo, su formación erudita sobre la historia oral y la cultura norteamericana. Esto expresa el grado de conocimiento que debe construir quien hace historia oral acerca de aquello que pretende comprender. Así como Gramsci nos decía que la historia de un partido debía constituirse en la historia de la totalidad nacional, Portelli, con la excusa de construir la historia de un cantautor o de una canción, cimienta una historia global.Facultad de Humanidades y Ciencias de la Educació

Diseño de un sistema de control de calidad en el proceso de la obtención de fibras de algodón para mejorar la productividad en la planta desmotadora de Sociedad Industrial Moche Norte SAC

El presente trabajo tuvo como objetivo la investigación de un Diseñar de un sistema de control de calidad en el proceso de la obtención de fibras de algodón para mejorar la productividad en la planta desmotadora de Sociedad Industrial Moche Norte SAC. El modelo fue desarrollado para ser aplicado en el área de Producción de desmotado de algodón en Sociedad Industrial Moche Norte SAC. Con la finalidad de mejorar la productividad a su planificación que le permita orientar a sus actividades a una mejor la calidad de los fardos de algodón e incrementar su productividad. Se analizó el proceso de Desmotado de Algodón utilizando para esto el diagrama de flujo del proceso, balance de materia y energía, se identificó la maquinaria y equipos, orientado a visualizar el entorno donde y como se desenvuelve el proceso productivo de desmotado de la planta desmotadora en estudio. Así mismo la descripción de todos los proceso antes, durante y después del desmotado del algodón. Se realiza un diagnostico actual de la empresa, para tener presente como se realiza el diseño de un sistema de control de calidad en el proceso de la obtención de fibras de algodón y así poder generar propuestas que puedan apoyar al área de Producción. Mediante el análisis de productividad actual se determinó que la productividad mejora teniendo en cuenta su producción en quintales, costos de producción, precios y el costo agregado por el sistema de control de calidad aplicado. Además el estudio nos permitió determinar que mediante un diseño de un sistema de control de calidad en el proceso de la obtención de fibras de algodón se puede aumentar la productividad en comparación al plan actual de la empresa, obteniendo mejora de 32,75 QQ/H-H a 33,71 QQ/H-H. Se concluyó que la aplicación de undiseño de un sistema de control de calidad en el proceso de la obtención de fibras de algodón contribuye mejorar la calidad de fibras y la productividad de la empresa, lo que ayudara a la empresa a reafirmar algunas decisiones y a replantarse otras.Tesi

Novel broadside trisection filters employing nonresonating nodes

This work presents novel filter topologies implemented in microstrip technology. The topologies combine printed line resonators with non resonating nodes (NRN) to implement transmission zeros in a very flexible way. Depending on the number of resonators and NRN, the filtering response exhibits a single transmission zero either below or above the passband, or two transmission zeros, one at each side of the passband. Several examples are designed and validated, using the new proposed structures.The authors thank Ministerio de Educación y Ciencia of Spain, which has supported this work under Grant TEC2007- 67630-C03-02

Changes in Petrophysical Properties of the Stone Surface due to Past Conservation Treatments in Archaeological Sites of Merida (Spain)

Petrophysical properties, such as porosity, permeability, density or anisotropy de-termine the alterability of stone surfaces from archaeological sites, and therefore, the future preservation of the material. Others, like superficial roughness or color, may point out changes due to alteration processes, natural or man-induced, for ex-ample, by conservation treatments. The application of conservation treatments may vary some of these properties forcing the stone surface to a re-adaptation to the new conditions, which could generate new processes of deterioration. In this study changes resulting from the application of consolidating and hydrophobic treatments on stone materials from the Roman Theatre (marble and granite) and the Mitreo’s House (mural painting and mosaics), both archaeological sites from Merida (Spain), are analyzed. The use of portable field devices allows us to perform analyses both on site and in la-boratory, comparing treated and untreated samples. Treatments consisted of syn-thetic resins, consolidating (such as tetraethoxysilane TEOS) and hydrophobic products. Results confirm that undesirable changes may occur, with consequences ranging from purely aesthetic variations to physical, chemical and mechanical damages. This also permits us to check limitations in the use of these techniques for the evaluation of conservation treatments

Geomonumental Routes: a useful tool for popularising the built heritage

The Geomonumental Routes entail a new proposal for the popularization of architectural heritage based on the geological materials that have shaped it, their behaviour and decay and how to preserve them. These routes take into account both social and scientific perspectives, being a novel method for the knowledge, transfer and preservation of architectural legacy. The prefix «Geo» highlights the link between geology and monuments, as any human urban settlement is conditioned by the geology for its placement; also the main resources for building are extracted from the Earth. The role of the stone within the built heritage confers a major value to it, and by itself. A heller knowledge of stone as a building material accounts for a different way of preserving and valuing built heritage. Geomonumental Routes lake visitors on a journey from the surrounding area lo the inside of the monument. These Routes focus on aspects such as the building history of monuments, the construction materials and their sources, the location of the historical quarries, the conservation/deterioration condition in which the monuments are, and any past restoration work pe1formed in them. To date, the Institute of Economic Geology has developed six Geomonumental Routes in the Region of Madrid. These Routes are also very useful for bringing a great stimulus lo the architectural heritage which is less known and therefore less valued, such as traditional architecture which is usually excluded from tourist itineraries. Valuing heritage and recognising the need of preserving it, will contribute to awake more consciences towards the fact that sensitivity to inherited culture is a question of time