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1.
Library materials are susceptible to fungal deterioration. The paper constituents of archival materials are subjected to harmful physical and chemical processes as they are slowly consumed by fungi. Remediation of fungal contamination can be costly and risk further damage to fragile or previously degraded materials. Early detection of fungal growth would permit the use of relatively noninvasive treatments to remediate fungal contamination of artifacts before visible or lasting damage has occurred. Current methods used for the detection of microbial biomass, such as colony counts, microscopic biovolume estimation, and ergosterol analysis are expensive, time consuming, or are inappropriate for use with fungi. Beta-N-acetylhexosaminidase (EC 3.2.1.52) activity provides a rapid and reliable means of fungal detection on a variety of cultural heritage materials. Adapted for use on archival materials, fluorogenic 4-Methylumbelliferyl (MUF) labeled substrate N-acetyl-Beta-D-glucosamine (NAG) was used to detect fungal beta-N-acetylhexosaminidase activity. The fluorescence generated by minute quantities of fungi was quickly detected at an early stage of growth. The sensitivity of the assay was comparable to other biochemical techniques. The fluorometric assay was well-suited for early detection of fungal biomass on paper and assessment of the effectiveness of common remediation practices.  相似文献   

2.
This study presents characterizations of weathering forms of the same oolitic limestone from four quarries and eight monuments exposed on various environmental conditions focusing on the waterproofing effect of endolithic organic matter. Patinas were analyzed by X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), capillarity coefficient through weathered and unweathered sides, gypsum content and porous network morphology by epoxy resin molding. Study of weathering forms on old quarries indicates that lichens colonization (Verrucaria nigrescens and Caloplaca aurantia) can fill the superficial porous network with a dense network of lichenised fungal hyphae. Capillary coefficient measurement on natural and calcinated samples showed that endolithic organic matter can waterproof the stone and could act as a sulfate contamination barrier. Similar endolithic organic layer due to ancient lichens growth are found on some antique monuments of the Nîmes downtown and could explain their well-preserved state, unlike decayed 19th century churches that were never colonized by lichens.  相似文献   

3.
A new process using aminoalkylalkoxysilanes (AAAS) was developed recently for paper and book mass deacidification. This process is entirely novel in that, besides deacidifying, it also improves the mechanical properties of paper. In the present article, the properties of inhibition of fungal growth of the treated papers are investigated. It was found that the AAAS tested acted as surface-active antifungal agents when introduced in the paper, significantly reducing the growth of Aspergillus niger and Paecilomyces variotii, two fungal species commonly found in storage areas of libraries and archives. The AAAS which seemed the most efficient in preventing the fungal development was 3-aminopropylmethyldimethoxysilane (AMDES), functionalised with a primary amine. The effect was significant in the different papers tested which demonstrated the protection against the proliferation of filamentous fungi in vitro for papers treated with AMDES. The higher concentration of AMDES inside the paper proved to be the most effective. The highest efficiency was reached for AAAS uptakes around 6%. At this concentration the sporulation of the two strains was inhibited and the development of A. niger mycelia was highly reduced.  相似文献   

4.
The brownish spots known as foxing, commonly found on old paper artefacts contain sometimes structures, which look like filamentous fungi. Attempts to grow these structures in vitro have been always unsuccessful so far. In order to study the role of these biological elements in paper decay, it is essential to identify them. This study is aimed at the identification of isolates from these brownish areas by culture-independent approaches using molecular biology techniques. The two Internal Transcribed Spacers and the 5.8 S gene (ITS1-5.8S-ITS2) from the nuclear ribosomal DNA were amplified, cloned and sequenced. Following a preliminary treatment with cellulase from Trichoderma reesei, DNA extractions were successfully achieved directly from paper samples. From 22 selected stained spots from a book dating from the 19th century, 8 extracts of genomic DNA were entirely analysed, which yielded 145 sequenced clones. No DNA could be sampled in unstained areas. Multiple alignment of the ITS sequences and comparison with reference sequences published in the NCBI database allowed to identify 14 groups of fungi belonging mainly to the following genera: Aspergillus, Bjerkandera, Chaetomium, Gloeotinia, Penicillium, Polyporus, Saccharicola, Trichoderma and Ulocladium. Some of these fungi are cellulolytic species but are not commonly found as indoor contaminant in storage rooms of graphic documents. The majority of the foxing spots exhibited sequences identified as Penicillium minioluteum. Gloeotinia temulenta occurred also frequently. Few isolates such as Aspergillus japonicus, Aspergillus oryzae, Chaetomium globosum, Penicillium citrinum, Trichoderma citrinoviride, Ulocladium chartarum and Ulocladium cucurbitae were present in only 1 or 2 clones. One of the foxing spots produced only one type of sequence similar to both Cordyceps sinensis and Fusarium lateritium, which have identical sequences in this rDNA region. This molecular approach, simple and rapid, could provide additional data for further discussion on the origin of the phenomenon of biological foxing.  相似文献   

5.
Cemeteries are part of the cultural heritage of urban communities, containing funerary crypts and monuments of historical and architectural interest. Efforts aimed at the conservation of these structures must target not only the abiotic stresses that cause their destruction, such as light and humidity, but also biofouling by biotic agents. The purpose of this study was to assess the development of biofouling of several historically and architecturally valuable crypts at La Plata Cemetery (Argentina). Samples obtained from the biofilms, lichens, and fungal colonies that had developed on the marble surfaces and cement mortar of these crypts were analyzed by conventional microbiological techniques and by scanning electron microscopy. The lichens were identified as Caloplaca austrocitrina, Lecanora albescens, Xanthoparmelia farinosa and Xanthoria candelaria, the fungi as Aspergillus sp., Penicillium sp., Fusarium sp., Candida sp. and Rhodotorula sp., and the bacteria as Bacillus sp. and Pseudomonas sp. The mechanisms by which these microorganisms cause the aesthetic and biochemical deterioration of the crypts are discussed.  相似文献   

6.
Solid-phase microextraction (SPME)–gas chromatography (GC)–mass spectrometry (MS) has been applied to the analysis of acetic acid and furfural that are emitted from the fibres of Phormium tenax (Xanthorrhoeaceae) [New Zealand flax] during degradation. Accelerated hydrothermal ageing of fibres of the Ruawai cultivar of P. tenax for 55 days at 70 °C resulted in the production of acetic acid at a level greater or equal to 1.65 mg g–1 fibre. This corresponds to only 8.5% of the acetyl groups present in the fibres. These groups are an important source of acetic acid, which is capable of damaging the fibres. The rate of production of acetic acid suggests that a heritage object made from the fibres of P. tenax, that was stored in damp ambient conditions, would undergo significant deterioration after a relatively short period. Other volatile products released during ageing included furfural, a series of short to medium chain aliphatic aldehydes that were derived from the oxidation of long chain unsaturated fatty acids on the fibres and a small group of products that were derived from carotenoids. The levels of furfural were determined to be approximately 0.75% of the potential production but at these levels, furfural could contribute to unpleasant odours from unventilated items. Fibres from six cultivars of P. tenax were found to release acetic acid and furfural all at the same rate. The levels of acetic acid that can be generated from these fibres are sufficiently high that low moisture levels and continuous change of air is required to minimize degradation of cultural objects that are made from these fibres and displayed in museum halls.  相似文献   

7.
This paper presents a deformative and structural study of the Guarneri ‘del Gesù’ violin (1743) known as the ‘Cannone’. A structural assessment is fundamental to understanding the violin's compatibility with its residual function of musical instrument. The tuning of the instrument to a modern playing pitch during concerts could, in fact, cause stress resulting in plastic deformations of its structure. In order to understand the stress level to which the violin is subjected when tuned, several tests were performed. The forces acting on the bridge were measured, the geometry of the un-strung and of the tuned violin were acquired with a tri-dimensional scanner, the violin deformation was assessed by means of the computed surface deviation mesh and by measuring the deformation in selected lines, several sections of the violin were cut from the digital model and stress exerted on the sections was computed. The stress exerted on the neck, scroll and body were found to be very limited. More significant, albeit at a low level, was the stress exerted under the bridge between the sound holes. Mechanical stress exerted after tuning was found to be safe for the violin, if applied for a limited amount of time. This does not mean that the violin can be played freely, because the real strength of the material used in the violin is not known and mechanical stress during a concert must be added to time (viscous behaviour), moisture content variation (mechano-sorptive behaviour) and hygro-thermal stress, thus worsening the condition. The method presented here could be applied to compute the level of stress of any violin.  相似文献   

8.
Xuan paper is a type of Chinese handmade paper produced for traditional calligraphy and painting in China since the Tang Dynasty (618–907 AD), and is therefore an important cultural heritage material. In this study, the fluorescence and photochemical properties of Xuan paper were investigated. Xuan paper exhibits auto-fluorescence in the blue spectral range (450–500 nm) and UVA photolysis of the paper resulted in a substantial reduction in the blue fluorescence together with the formation of chromophores absorbing in the visible spectrum, resulting in photoyellowing of the paper. A more significant yellowing of paper was observed when irradiated in the dry state than under wet conditions. The associated photogeneration of hydrogen peroxide and superoxide from three types of Xuan paper samples during irradiation showed a correlation between the yields of reactive oxygen species and their relative yellowing rates. The results are interpreted in terms of sensitised photooxidation via a mechanism of electron transfer involving the fluorophores in their excited singlet states being responsible for the photodegradation of Xuan paper. SEM/EDS analyses were performed on the Xuan paper samples to investigate their morphological and elemental characteristics. Silica-containing fibres characteristic of a special rice straw that grows in siliceous soil were observed in all types of Xuan paper. Micron-sized calcium precipitates possibly formed from the “lime-steaming” manufacture process were shown to protect against the acidification of paper during accelerated thermal ageing.  相似文献   

9.
Leaves of common deciduous trees: the horse chestnut (Aesculus hippocastanum) and linden (Tilia spp.) from the park, near one of the most important cultural institutions, the National Library of Serbia, were studied as bioaccumulators of heavy metal (Cr, Fe, Ni, Zn, Pb, Cu, V, As and Cd) air pollution. The leaf samples were collected from the urban park exposed to the exhaust of heavy traffic. The May–September heavy metal accumulation in the leaves, and their temporal trends, were assayed in a multi-year period (2002–2006). Comparing the obtained concentration of the investigated elements from the beginning to the end of growing seasons, a significant rate of accumulation was determined for a majority of measured elements, and it was concluded that these tree species (horse chestnut and linden) can be used as bioaccumulators of the investigated heavy metals. The SEM-EDAX analysis of individual particles deposited on the leaves showed that the 50–60% belong to a class of fine particles (D < 2 μm), mainly of anthropogenic origin. Thus, the investigated tree species could be grown as a natural barrier against urban air pollution in the vicinity of libraries, museums and other buildings for cultural heritage storage.  相似文献   

10.
The brown carpet beetle Attagenus smirnovi, Zhantiev 1973 (Coleoptera: Dermestidae) is an important pest of objects of organic origin in museums of cultural and natural history in Europe. Future climate changes are expected to lead to increasing temperatures, which will affect the pest status of this species. In the present study a laboratory investigation was conducted to elucidate the effect of temperature and humidity on the amounts of organic material consumed by larvae of A. smirnovi. In the case of new and old skin, consumption was approximately twice as high at 28 °C compared to 20 °C. Wool was consumed in the greatest amounts: 169 mg of wool was consumed in three months by 30 A. smirnovi larvae. The expected future climate changes in Scandinavia are assumed to lead to higher temperatures in museums and stores where climate is not regulated. Updated data on the present distribution of A. smirnovi in Europe show that it is widespread and common, also in regions with a climate that does not support its survival out of doors. Thus, dispersal of this pest probably only rarely occurs by flight, but usually with human activity. Due to the widespread distribution of A. smirnovi, it is likely that damages in museums and collections in Scandinavia due to this pest will increase as climate changes come into effect.  相似文献   

11.
This study is aimed at an assessment of the properties of two polymeric products applied to Norway spruce (Picea abies) and White poplar (Populus alba) wood species. It contributes to ongoing research experiments on the consolidating properties of two synthetic resins and their potential synergic action on wood, resulting from their different interaction with the substrate: Paraloid B72 and Regalrez 1126. Experiments were carried out on a series of samples of the two wood varieties. The consolidants were applied alone and one after the other, with one coat of Regalrez and then one of Paraloid. Porosity and variations in pore size distribution were ascertained by mercury intrusion porosimetry (MIP). Colorimetric and IR spectroscopic measurements were also taken before and after aging by solar radiation and freeze/thaw cycles, to verify the possible slowing of photodegradation of the treated wood and the consolidating resistance. Results confirm that both products penetrate the wood with a different behaviour. After double treatment with Regalrez + Paraloid, a significant advantage was observed in terms of mechanical resistance and pore size distribution, although no advantages as regards resistance to photo-oxidizing processes or colour changes were observed.  相似文献   

12.
The influence of chemical treatments based on novel organic products on the consolidation of deteriorated wood by insect attack was evaluated on two hardwoods and one softwood: fir (Abies alba), beech (Fagus sylvatica) and deciduous oak (Quercus sp.). Degraded and intact specimens of the three wood species were impregnated with two different chemical treatments aimed to verify the potential synergic action of the novel products on wood. Then, the specimens were subjected to bending, compression parallel to the grain, impact, hardness and water absorption tests. Untreated specimens of the same botanical species, both degraded and non-degraded, were examined for comparison purposes. The experimental results showed a different effectiveness of the proposed chemical treatments to improve the mechanical and absorption properties of degraded wood. The most effective treatment was the one assuming the concurrent use of the studied novel consolidants. The species more susceptible of the enhancement in mechanical properties were fir and beech. The observed differentiations were most likely caused by the different structure of the botanical species considered, leading to a consequent different product penetration in the wood structure. The dimensional stability in terms of water repellent and antiswelling efficiency, after a three-month immersion in deionized water, was found to improve in all the treated wood specimens. Overall, experimental results showed that the impact of the chemical treatments was higher on degraded samples than on intact ones.  相似文献   

13.
The “marble” Portasanta from Caldana (Grosseto, Italy) takes its name from the strict resemblance to the ancient Marmor Chium (also this called Portasanta) coming from the island of Chios in Greece. In this work, a complete characterization of the Italian Portasanta was made: chemical (X-ray fluorescence and isotopic analyses), mineralogical (X-ray diffraction on the bulk sample and on insoluble residue after acid attack), physical (water accessible porosity and imbibition coefficients), petrographical (optical microscopy) and mechanical (compressive strength test) analyses have been carried out in order to obtain a better distinction between Italian and Greek “marble”, sometimes mistaken. The Portasanta from Caldana (Italy) was quarried surely in the sixteenth century, but a possible use of this material during Roman time is still in doubt. The study of samples from some Tuscan archaeological sites (Torraccia di Chiusi, Siena and Roselle, Grosseto) allows us to confirm the use of Portasanta from Chios for the Torraccia site and that of Caldana for Roselle.  相似文献   

14.
A new conservation process was developed for archaeological iron-wood artefacts. Metal part protection was achieved by adding a corrosion inhibitor (Hostacor IT®) in the polyethylene glycol (PEG) soaking solutions. Nevertheless, a significant microbiological growth was observed in the baths and around the objects. From the different soaking solutions, 23 bacterial strains and 12 strains of filamentous fungi were isolated. Adding compatible biocide has been absolutely essential to allow the PEG and Hostacor IT® to be effective. Among biocides tested, Dowicide®A that contains sodium o-phenylphenate is the most efficient. As shown by electrochemical measurements (corrosion potential, intensity and polarization resistance), this biocide does not destabilize the formation of protective film created by Hostacor IT®. There is no competition of adsorption between Hostacor IT® and Dowicide®. In the presence of Dowicide®, Hostacor IT® acts more quickly and in a significant way.At the concentration of 3000 ppm, Dowicide® is effective to protect the aqueous solutions of PEG 400+ Hostacor IT® from the development of the selected microorganisms. Adding the biocide at the beginning of the object impregnation was the most effective way to prevent bacterial and fungal growth. Tests in real conditions showed that after two months of impregnation, solutions reminded clear and no biofilm was observed around artefacts.  相似文献   

15.
The frescoes of Livia’s villa at Prima Porta, Rome, are the most famous representations of Roman gardens. The painted flora is analyzed from the scientific viewpoint and previous identifications are critically discussed. Here, 24 different species are described, giving information on the taxonomic, and phytogeographic position. Most of them belong to the spontaneous elements present in the Mediterranean forests, maquis and grasses of Southern Italy, such as Arbutus unedo, Laurus nobilis, Nerium oleander, Quercus ilex, Quercus robur gr., Cornus mas, Myrtus communis, Phyllitis scolopendrium, Viola reichenbachiana, Chrysanthemum coronarium, Anthemis cotula, or widely cultivated, such as Cupressus sempervirens, Cydonia oblonga, Pinus pinea, Punica granatum, Papaver somniferum, Rosa centifolia, Phoenix dactylifera. A symbolistic purpose of the pictures is also clearly evident.  相似文献   

16.
This work faces the problem of detecting decay zones from color images of stone materials. In Cultural Heritage, the extraction of degradation regions from images of ancient monuments represents an important step forward in studying and analyzing the state of preservation of historical buildings. Generally the decay diagnosis is provided by “naked eye” analysis done by expert scientists “walking around” the artifact and recording the conservation state of each individual element they observe. In addition to this kind of investigation, the application of an image segmentation strategy to color images of stony materials can be used in order to extract regions characterized by a visible chromatic alteration, changes in color, for example, as oxidation or concretion. This paper features a color image segmentation approach founded on the fast marching numerical method. We have applied this technique for its possibility to work locally, that is, only the contour of the region under study is processed. In addition to this method, we present a global approach, that is, the possibility to extract decay regions from the entire image; these regions are spatially disconnected but with similar colorimeter value. The main aim of the present work is to provide a tool that helps the expert to contour the degraded regions. In this sense even if the results of the proposed procedure depend on the expert evaluation, the approach can be a contribution to improve the efficiency of the boundary detection process. The study case concerns the impressive remains of the Roman Theatre in the city of Aosta (Italy). In the image segmentation process the color space L*a*b* is utilized.  相似文献   

17.
Forty-six Streptomyces strains were isolated from paintings and stone surfaces from Tell Basta and Tanis tombs (80 km south-east Cairo, Egypt). Eight of these strains were selected to determine their sensitivity against 13 antibiotics. In general, high levels of resistance could be observed. Gentamycin, spiramycin and doxycycline were the most effective antibiotics against the majority of strains under study. Due to the observed antibiotic resistances, gamma irradiation was studied as a possible alternative to inhibit microbial growth. Isolated bacteria were exposed to different doses of gamma irradiation (5, 10, 15, 20 and 25 kGy). The growth of all Streptomyces isolates except S. canarius was completely inhibited at 25 kGy. The applied doses of gamma irradiation did not cause any observable alterations or colour changes to pigments and binding media (arabic gum, animal glue and egg-yolk) used in the paintings.  相似文献   

18.
This paper describes GPR (ground penetrating radar) surveys performed inside the crypt of the San Miguel de los Reyes Monastery (1546–1835) in order to detect the exact location of its founders' remains, the Dukes of Calabria (16th century). This Monastery was erected to house their family mausoleum and the bodies of the founders were buried near the high altar of the church (1645). However, in the 18th century, the tombs were exhumed to provide them with a worthier burial site: the crypt below the high altar. There is no documentation specifying the exact location of the tombs inside the crypt. Therefore, in order to reveal the exact location of the tombs the GPR survey was conducted inside the crypt.In our specific study, the available historical documentation led us to suppose that the Dukes of Calabria's remains were inside their mausoleums. However, after having performed the GPR analysis, we discovered that the mausoleums were solid and not hollow. The project required data collection on four areas in the crypt: the altar crypt, the Fernando de Aragón mausoleum, the Germana de Foix mausoleum and the floor between the two mausoleums and the altar.In this study, we have processed the GPR records in three different ways: the radargrams were processed in a standard manner, a detailed spectral analysis of all anomalous areas was carried out, and finally a 3D representation was generated. After this complete analysis we concluded that the bodies were not located inside their mausoleums, because they were shown to be solid. Besides, a burial site was located in the crypt subsurface near the Germana de Foix mausoleum, in which four different elements could be identified. Two of them may well be the tombs of the Dukes of Calabria and the other two the tombs of the Germana de Foix sisters.The results obtained in this survey are a good example of GPR application as an efficient and respectful tool for use in Cultural Heritage restoration studies, providing it with a very useful technique for similar projects such as those carried out in the restoration of historical buildings and those in which the elements to be examined are beneath a shallow coating of material.  相似文献   

19.
This paper is concerned with the role of cultural heritage in coastal areas, including land belts and coastal marine waters in the prospect of operating sustainable development-aimed strategies. It is a part of the investigations carried out in the framework of the Progetto Finalizzato Beni Culturali (Special Project Safeguard of Cultural Heritage) convened by the Consiglio Nazionale delle Ricerche (CNR, the Italian National Research Council). Essentially, it aims at contributing to the discussion on how the mise-en-valeur of the coastal cultural heritage may be framed within integrated coastal management programmes. In this view, the discourse on the coastal cultural heritage runs along this pathway: (i) global (climatic) change and globalisation are assumed to be the key components of the external environment with which the coastal area interacts; (ii) the conceptual framework of coastal management, as it can be deduced by the background guidelines from Agenda 21 (United Nations Conference on Environment and Development, UNCED), is considered; (iii) the legal framework, which the coastal area is characterised by, is taken into account by focusing on its implications on the management patterns. At this point, attention is concentrated on the role of cultural heritage in the framework of integrated coastal management approaches. It is considered, how this pivotal component of the coastal area has been dealt with bythe intergovernmental organisations. Special consideration is attributed to the European Code of Conduct for Coastal Management Zones, since it considers the ecological patrimony and cultural heritage as giving shape to a unique ethically-endowed reality, which materialised through landscapes and seascapes. The final step consists of the design of a tentative Code of Conduct for Coastal Cultural Heritage consisting of some background and operational principles.  相似文献   

20.
This research focuses on the characterization of historical mortars collected from a covered dockyard, called tezone 105, erected in the Arsenal of Venice during the XVI century. The mortars date back to different building phases. A stratigraphical analysis of tezone 105 has proposed a chronology of building interventions. The building phases recognized by the stratigraphical analysis belong to the original structure (XVI century) and to later interventions from XVI to XX century. Mortar samples are investigated by granulometric analysis, infrared spectroscopy (FT-IR), simultaneous thermal analysis (DSC/TG) and X-ray diffraction analysis (XRD) in order to identify the technology peculiar of each building phase. Mortar sampling was carried out on indoor masonry and foundation. Masonry mortars appeared to be characterized by the application of air-hardening binders, whereas foundation mortars were characterized by hydraulic binders.  相似文献   

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