29 research outputs found
Técnicas no destructivas para la monitorización cuantitativa y cualitativa de procesos de biodeterioro en materiales pétreos
7 páginas, 4 figuras, 1 tabla, 9 referencias. Trabajo presentado al IX Congresso Ibérico de Arqueometria, celebrado del 26-28, octubre, 2011, en Lisboa, Portugal[ES]: La colonización biológica de la piedra es uno de los principales problemas para la conservación de edificios y monumentos. El biodeterioro
de la piedra ha sido estudiado empleando metodologías para la identificación de los microorganismos y para el seguimiento de su acción
que, en su mayor parte necesitan de una gran inversión de tiempo y de un muestreo extensivo. Muchos de los procedimientos de muestreo
empleados pueden, incluso, convertir a los propios investigadores en agentes de deterioro. En este estudio se propone el uso de técnicas
para la detección temprana y monitorización de colonizaciones microbianas sin necesidad de contacto, como manera de contribuir al objetivo
de preservar el patrimonio cultural.[EN]: Biological stone colonisation is one of the main problems related to the conservation of monuments and buildings. Stone biodeterioration
has been assessed by several authors using time-consuming and extensive sampling methodologies for microbial identification and
the follow-up of their action. However, most sampling procedures may convert the own researchers in deterioration agents. In this study
the use of non-contact techniques for early detection and monitoring of microbial colonisations is proposed, as a contribution to the goal of
the preservation of cultural heritage.AZM agradece a la Fundação para a Ciência e a Tecnologia - Ministério da Ciência, Tecnologia e Ensino
Superior su beca postdoctoral (sfrh/bpd/63836/2009). Este estudio ha sido financiado parcialmente por el
Centro de Petrologia e Geoquímica do Instituto Superior Técnico (CEPGIST) y por el proyecto CONSOLIDER
TCP CSD2007-00058. Este trabajo ha sido cofinanciado con fondos FEDER.Peer reviewe
国際関係における権力概念 -議論の整理と方法論の検討-
The importance of stone colonisation by microorganisms has led to an extensive literature on mechanisms and rates of physicochemical degradation of stone surface, both in laboratory and field contexts. Biological colonisation of a stone surface depends on intrinsic stone parameters like mineral composition, texture, porosity, and permeability, as well as on environmental parameters. In the present study, quantification of stone surface roughness and its relationship to epilithic colonisation was demonstrated for three types of limestones throughout non-destructive techniques, namely optical surface roughness instrument and digital image analysis. According to the roughness average (Ra) and mean roughness depth (Rz) determined for Ançã limestone, Lioz limestone and Lecce stone, it can be concluded that great surface roughness stones render them prone to microbial colonisation.La colonización de la piedra por microorganismos ha generado una extensa literatura sobre los mecanismos y tasas de degradación fisicoquímica de las superficies pétreas, tanto en laboratorio como en estudios de campo. La colonización biológica de piedra de construcción depende de parámetros intrínsecos como son su composición mineral, textura, porosidad y permeabilidad, así como de parámetros ambientales. Este estudio demuestra la relación entre la rugosidad superficial de la piedra y la colonización epilítica, cuantificada en tres tipos de caliza mediante técnicas no destructivas: medida de la rugosidad superficial usando un perfilómetro óptico y análisis digital de imágenes. De acuerdo con la rugosidad media aritmética (Ra) y la amplitud media de rugosidad (Rz), determinadas para la caliza de Ançã, la caliza de Lioz y la piedra de Lecce, puede concluirse que las piedras con alta rugosidad superficial son más propensas a la colonización microbiana
An integrated approach for assessing the bioreceptivity of glazed tiles to phototrophic microorganisms
18 páginas.-- 7 figuras.-- 5 tablas.-- 63 referenciasA laboratory-based methodology was designed to assess the bioreceptivity of glazed tiles. The experimental set-up consisted of multiple steps: manufacturing of pristine and artificially aged glazed tiles, enrichment of phototrophic microorganisms, inoculation of phototrophs on glazed tiles, incubation under optimal conditions and quantification of biomass. In addition, tile intrinsic properties were assessed to determine which material properties contributed to tile bioreceptivity. Biofilm growth and biomass were appraised by digital image analysis, colorimetry and chlorophyll a analysis. SEM, micro-Raman and micro-particle induced X-ray emission analyses were carried out to investigate the biodeteriorating potential of phototrophic microorganisms on the glazed tiles. This practical and multidisciplinary approach showed that the accelerated colonization conditions allowed different types of tile bioreceptivity to be distinguished and to be related to precise characteristics of the material. Aged tiles showed higher bioreceptivity than pristine tiles due to their higher capillarity and permeability. Moreover, biophysical deterioration caused by chasmoendolithic growth was observed on colonized tile surfaces.This work was supported by the Portuguese Foundation for Science and Technology (FCT) [grant SFRH/BD/46038/2008; project UID/EAT/00729/2013]. A.Z. Miller acknowledges support from a Marie Curie Intra-European Fellowship of the European Commission’s 7th Framework Programme [PIEF-GA-2012-328689]. J.P. Veiga and H. Águas acknowledge funding by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT [project UID/ CTM/50025/2013]. This work was supported by the European Commission’s 7th Framework Programme, through the Marie Curie International Research Staff Exchange Scheme [NANO_GUARD (PIRSES-GA-2010-269138)].Peer reviewe
Evaluación de la influencia de la rugosidad superficial sobre la colonización epilítica de calizas mediante técnicas sin contacto
Laboratory-induced endolithic growth in calcarenites: biodeteriorating potential assessment
This study is aimed to assess the formation of photosynthetic biofilms on and within different natural stone materials, and to analyse their biogeophysical and biogeochemical deterioration potential. This was performed by means of artificial colonisation under laboratory conditions during 3 months. Monitoring of microbial development was performed by image analysis and biofilm biomass estimation by chlorophyll extraction technique. Microscopy investigations were carried out to study relationships between microorganisms and the mineral substrata. The model applied in this work corroborated a successful survival strategy inside endolithic microhabitat, using natural phototrophic biofilm cultivation, composed by cyanobacteria and algae, which increased intrinsic porosity by active mineral dissolution. We observed the presence of mineral-like iron derivatives (e.g. maghemite) around the cells and intracellularly and the precipitation of hausmannite, suggesting manganese transformations related to the biomineralisation.Fundação para a Ciência e a Tecnologia (FCT
Science and technology for the conservation of cultural heritage
El libro contiene los Proceedings of the International Congress on
Science and Technology for the Conservation of Cultural Heritage, celebrado del 2-5 de octubre 2012, en Santiago de Compostela, España.-- Complementary Action HAR2010-11432-E funded he celebration of the Congress and the publication of the proceedings TechnoHeritage coordinator Prof. Dr. Cesáreo Sáiz-Jiménez is acknowledged for this continuous help and support.From 2nd to 5th October 2012 an International Congress on Science and Technology for the conservation of Cultural Heritage was held in Santiago de Compostela, Spain, organized by the Universidade of Santiago de Compostela on behalf of TechnoHeritage Network. The congress was attended by some 160 participants from 10 countries, which presented a total of 145 contributions among plenary lectures, oral, and poster communications. The congress was dedicated to eight topics, namely (1) Environmental assessment and monitoring (pollution, climate change, natural events, etc.) of Cultural Heritage; (2) Agents and mechanisms of deterioration of Cultural Heritage (physical, chemical, biological), including deterioration of modern materials used in Contemporary Art and information storage; (3) Development of new instruments, non invasive technologies and innovative solutions for analysis, protection and conservation of Cultural Heritage; (4) New products and materials for conservation and maintenance of Cultural Heritage; (5) Preservation of industrial and rural heritage from the 19th and 20th centuries; (6) Security technologies, Remote sensing and Geographical Information Systems for protection and management of Cultural Heritage; (7) Significance and social value of Cultural Heritage; and (8) Policies for conservation of Cultural Heritage.
This volume publishes a total of ninety-three contributions which reflect some of the most recent responses to the challenge of cultural assets conservation.Peer reviewe
Science and technology for the conservation of cultural heritage: A European view
2 pages.-- Proceedings of the International Congress on Science and Technology for the Conservation of Cultural Heritage, held 2-5 october, Santiago de Compostela, España.European Cultural Heritage is the product of the historical development of the myriad of
civilizations that contributed over millennia to the creation of the historical, geographical and
cultural concept of Europe. This cultural heritage plays a capital role in enriching and enhancing
the quality of life of European peoples, in aiding in the understanding of our historical origins,
problems, solutions and self-conscience as a differentiated historical entity, as well as in the
development of a pool of solutions to environmental and construction-related problems.Complementary Action HAR2010-11432-E funded the celebration of the Congress and the publication
of the proceedings. TechnoHeritage coordinator, Prof. Dr. Cesareo Saiz-Jimenez is
acknowledged for his continuous help and support.Peer reviewe
Microalgae as biodeteriogens of stone cultural heritage: qualitative and quantitative research by non-contact techniques
14 pages, 3 figures, 38 references. El libro de referencia consta de 475 páginas y la publicación es el capítulo 13 del mismo.Biological colonisation of stone is one of the main problems related to monuments
and buildings conservation. It is amply recognised that microalgae have the greatest
ecological importance as pioneer colonisers of stone materials, conducting to aesthetic,
physical and chemical damages. Their deterioration potential is related with their
photoautotrophic nature, using the mineral components of stone substrates and sunlight as
energy source without any presence of organic matter.
Stone biodeterioration by microalgae has been assessed by several authors. Most of
the employed methodologies for microbial identification and monitoring are timeconsuming
and require extensive sampling. In addition, the scaffolding and sampling
procedures required may also transform the researcher in a biodeteriorating agent itself.
In this chapter, non-contact techniques for colonisation detection and monitoring are
proposed in order to fulfil the mission of heritage preservation. In vivo chlorophyll a
fluorescence and digital image analysis were applied to estimate microalgal biomass and to quantify coverage of limestone samples artificially colonised by algal communities.
The results showed that Ançã and especially Lecce limestones were extensively colonised
on their surfaces revealing significant epilithic growth, whereas Escúzar and San
Cristobal limestones were endolithically colonised by photoautotrophic microorganisms.
The easily handled, portable and non-destructive techniques proposed allow the
understanding of stone biodeterioration processes avoiding contact and damaging of the
objects, which ensures a wide field of application on cultural heritage studies and the
design of appropriate conservation and maintenance strategies.This study has been partially financed by Centro de Petrologia e Geoquímica do Instituto
Superior Técnico (CEPGIST). The authors are grateful to REQUIMTE/CQFB, Departamento
de Química, Universidade Nova de Lisboa (Portugal). This is a TCP CSD2007-00058 paper.Peer reviewe
Were late prehistoric stelae painted? Digital image analysis-based research of the late prehistoric stelae of Mirasiviene (Lora del Río, Sevilla) and Montoro (Montoro, Córdoba), South Spain
The dictionary defines a stela as > a usually carved or inscribed stone slab or pillar used for commemorative purposes >. Despite the vague commemorative idea implicit in the concept, we are currently far from having an unambiguous interpretation of Iberian late prehistoric stelae. A formal question periodically updated in Iberian archaeology is that of the surface treatment of the late prehistoric stelae. These stone monuments, usually engraved following several models, could have been painted, as various apparent colours randomly detected suggest. A complete study on a wide series of stelae would clarify the question, but due to different factors (mainly of an economic nature, but also linked to the need of sampling in order to perform most analytical techniques), this kind of study has not yet been conducted. This contribution presents the methodology and results of the study of the external appearance of two engraved Spanish stelae: Mirasiviene, which is a typical Late Bronze Age stela from the southwestern Iberian Peninsula, and Montoro, a probably pseudo-epigraphic stela from the Iron Age. These stelae remain unpublished, although the complete publications of both them are currently under preparation. The image analysis protocol implemented on these stelae was designed from an extensive previous experience in rock art recording and involved the decorrelation of standard RGB images by means of Principal Components Analysis.Peer Reviewe
Análisis de imagen para la evaluación de la bioreceptividad de materiales utilizados en el Patrimonio Cultural.
2 páginas, 6 referencias. Comunicación oral que publica el Libro de Resúmenes de la 9ª Reunión de la Red Temática del CSIC de Patrimonio Histórico y Cultural. Sevilla, 4 y 5, marzo, 2008.En los últimos años, muchos autores conceden gran importancia al deterioro biológico, o
biodeterioro de materiales de construcción, considerando que la colonización biológica es uno
de los principales problemas para la conservación del Patrimonio Cultural en piedra. Por ello, la
comprensión de las causas del biodeterioro de monumentos y edificios históricos tiene
importancia fundamental en la adquisición de nuevos tratamientos de restauración y
prevención.El presente estudio se ha llevado a cabo en el marco de los proyectos
“Aplicación de técnicas de teledetección a la monitorización del biodeterioro y documentación
de bienes culturales en ambientes hipogeos”, PIE 200440E327 (CSIC), “Comunidades
microbianas asociadas al desarrollo de eflorescencias en monumentos andaluces:
determinación de su actividad metabólica mediante técnicas moleculares y papel en el
biodeterioro”, P06-RNM-02318 (Consejería de Innovación, Ciencia y Empresa, Junta de
Andalucía) y “Monitorización de la bioreceptividad de materiales empleados en el Patrimonio
Cultural”, 2007PT0041 (CSIC-FCT). LL agradece al CSIC el proyecto 200740I011. Se agradece
a la Fundação para a Ciência e Tecnologia – MCIES la beca predoctoral de AZM.Peer reviewe