Search

• Redefined solubility parameters in practical calculations. • Solvent selection on a solid thermodynamic basis. • Property prediction for bulk phases and interfaces. A large portion of solvent selection and solubility calculations by Conservators of Works of Art are still done with solubility parameters or its Teas variation scheme. In spite its empirical character entailing the risk of notable failures, this is a simple and often successful scheme. The central objective of the present work is to provide with an alternative simple method for the above and related calculations but with sound thermodynamic basis for more reliable estimations. The method is known in the literature as the Partial Solvation Parameter (PSP) approach. With the Conservator in mind, the method is simplified and the working equations are reported in their simplest analytical form. Examples of calculations are reported which will facilitate understanding and efficient use of the method. The calculations cover bulk phases as well as interfaces and may be used for the rational design of conservation and numerous other processes. [ABSTRACT FROM AUTHOR]

Highlights • New study on materials and technological processes of stucco devotional reliefs. • Micro samples from 22 reliefs after 15th century Florentine masters were analysed. • FEG-SEM, XRD and PIXE provided microstructural and compositional analyses. • Outcomes pointed out a common use of gypsum plaster for all the artworks studied. • First hints on raw material provenance compatible with main scholars' hypothesis. Abstract The production of devotional reliefs particularly flourished in 15th century Florence, where models from Renaissance Masters actually became the object of a serial-production. One of the materials mostly used to this purpose was the so-called "stucco". This preliminary work focuses on the multiscale structural and compositional analysis of micro samples from 22 representative stucco low reliefs attributed to the workshops of renowned Masters. The identification and characterisation of main mineralogical phases showed that the material used to make these reliefs consists in a gypsum-based plaster. Data from both X-ray diffraction and Particle induced X-ray emission allowed to gather also information on secondary mineral phases (sulphates, carbonates and clay minerals, together in few weight percentage maximum) and trace elements. Through an extensive comparison of all the mineralogical and compositional data collected on the corpus of artworks, first insights on workshop practices and raw material used have been enlightened. [ABSTRACT FROM AUTHOR]

Abstract The removal of aged pressure sensitive tapes (PSTs) from contemporary drawings is a frequent and challenging task for paper conservators: in this work, an innovative method to overcome this issue is presented. Aged PSTs are largely found on paper artworks due to their use for mending, mounting and framing operations. Nevertheless, they may provoke several drawbacks on artworks (e.g. media bleeding and adhesive mass migration): the necessity of their removal promoted the development of several methodologies, but they all pose risks to both artefacts and conservation professionals. We propose a method involving polymeric gels able to load a "green" solvent, pertaining to the class of alkyl carbonates, which efficiently interacts with PSTs components; the embedment of the solvent into the gel network allows a feasible and effective intervention where the gel is directly applied on the top surface of the PST: the solvent gradually penetrates through the plastic layer of the PST (as proved by laser scanning confocal microscopy measures), swelling the underlying adhesive. In this way, the solvent-artwork contact is controlled. In order to optimize the processing costs and final properties of the gels, three formulations of poly (ethyl methacrylate)-diethyl carbonate (PEMA-DEC) organogels were synthesized, using different diluents and additives. A thorough physicochemical investigation of the systems was performed by means of rheology, gravimetric analysis, thermogravimetry, and IR Spectroscopy. After assessment on representative mock-up samples, the developed systems were successfully used for the removal of six aged PSTs from a drawing on paper by Keith Haring. [ABSTRACT FROM AUTHOR]

Highlights • A total of 150 fungal isolates (24 genera and 43 species) were obtained by the seasonal air-sampling. • Active fungal growth was present on the artworks. • Matching species between air samples isolates and the artworks suggests cross-contamination. • Low fungal contamination levels inside the repository did not represent a lack of biological threat. • Existing guidelines on fungal contamination still lack relevant data regarding species identification. Abstract Biodeterioration is a topic of ever-growing concern and is particularly relevant in the context of cultural heritage conservation, since artworks and monuments provide diversified ecological niches for microorganism colonization. Despite all the gathered knowledge in recent years, current established norms and accepted contamination thresholds have a prominent focus on human health and air quality preservation. Nonetheless they still are not enough or are not adequately applied for cultural heritage preservation. In the light of this study within a very important Museum from Coimbra (Portugal), the current knowledge and accepted norms are discussed. Despite the meticulous control of environmental parameters inside this art repository, the presence of fungal colonies was unexpectedly detected on wooden sculptures and paintings that were deposited inside a custom-built room. Contaminated art objects were sampled for fungal isolation and identification, along with seasonal indoor air sampling, for a one-year period. Molecular biology methods complemented with morphological observation were used for the identification of fungal organisms. Direct sampling of 8 contaminated paintings allowed the retrieval of 10 fungal isolates (3 different genera and 4 different species). In addition, 19 fungal isolates (5 different genera and 9 different species) were retrieved from 7 contaminated wooden sculptures. The air sampling process provided a total of 150 isolates (24 different genera and 43 different species), from which the most common genera were Aspergillus , Cladosporium and Penicillium , and the most frequent species were Aspergillus versicolor , Cladosporium cladosporioides , Penicillium copticola and P. corylophilum. Although the number of airborne CFU was considerably low in all seasons, some fungal species with known biodeterioration capability and adverse human health effects were found. The relevance of air contamination monitoring as a single tool for biodeterioration risk assessment is discussed, as are the currently available norms and recommendations. Preventive measures are advised and considerations are made regarding potentially more effective approaches. [ABSTRACT FROM AUTHOR]

The study of fragile artworks kept in museums requires mobile devices, short time of analysis and minimal disturbance to insure their good preservation. In situ reflectance spectroscopy and spectrofluorimetric studies are mostly developed for pigment characterization. A recently-designed μspectrofluorimeter (LED μSF) dedicated to in situ measurements, that uses UV-light emission diodes (LED) as excitation sources, was used to verify its potentiality for the identification of pigments and dyes. The colours of five Japanese woodblock prints from the Museum of Zaragoza (Spain) were studied by the combination of UV-VIS-IR spectroscopies and hand-held energy dispersive X-ray fluorescence spectrometer (HHED-XRF), together with Raman Spectroscopy. This study focused on the analysis of red and blue colours in prints by Koryūsai, Utamaro and Eisen (18th–19th centuries). The interpretation of the in situ fluorescence emission spectra could be rather difficult because of the variety of pigment mixtures, natural ageing of colorants and fluorescence of the support (paper), that could lead to spectral changes or band shifts. The combination with diffuse reflectance spectroscopy (DRS), hyperspectral imaging techniques (HSI), and HHED-XRF completed the interpretation of these results. A specific database was built analyzing reference samples made in accordance with Japanese printings techniques and materials. Inorganic and organic red (vermilion, red lead, cochineal, red safflower) and blue (Prussian blue, indigo, dayflower) pigments were used alone or as a mixture to modify the hues. The identification of Prussian blue could be a clue about the relations existing between East and West and, its presence sometimes questioned the dating of some early printings. [ABSTRACT FROM AUTHOR]

The majority of the studied artworks were altarpieces, sculptures and/or wood-based works from different periods. Non-traditional gilding techniques have been first described in this paper, such as those that employ materials as oil in the gilding on bole, glue and bole with lead white in mordant gilding, vermilion in the preparation layers; and brass gilding or those with aluminium, lead chromate, mica or corla trying to imitate the golden hue in restoration or repaint processes. For the determination of the composition of the different gilded layers, spectroscopic techniques, such as FTIR and micro-Raman, and SEM-EDX elemental chemical analyses were successfully used. [ABSTRACT FROM AUTHOR]

Image inpainting restores lost or deteriorated parts of images according to the information of known regions. Criminisi has proposed an effective exemplar-based inpainting method, which has the advantages of both texture synthesis and diffusion-based inpainting. Yet, it has its own flaws of fast priority dropping and visual inconsistency. In this paper, we propose a space varying updating strategy for the confidence term and a matching confidence term to improve the filling priority estimation. We propose structure consistent patch matching to take the distribution of source and target patch differences into account. Fast Fourier transform is adapted for full image searching to achieve better and faster matching results. Experimental results are given to demonstrate the improvements made by our proposed method. [ABSTRACT FROM AUTHOR]

Bread-made artifacts are the products of an ancient creative tradition in some parts of Sardinia. While early objects were intended for pagan events (e.g., grain harvest), later artworks were specifically made for Catholic celebrations, such as Christmas and Easter. Unfortunately, the cultural heritage linked to these objects is endangered by Sitophilus granarius (L.), a tiny insect that causes irreparable damage, such as ruptures and galleries through an intense boring action. In this work, we have evaluated the potential for the coating technology to protect bread-made artifacts from entomatic attack. Within this scope, a nanocomposite coating and an active coating were prepared, and the coated objects were characterized in terms of optical, mechanical, and insect-resistant properties. Overall, the deposition of the coating did not negatively impact the appearance of the objects, although some differences were detected instrumentally in terms of color and gloss. In addition, both coating formulations decreased the Young's modulus of the samples subjected to a flexural test, which was attributed to the plasticizing effect of the poly-methyl methacrylate and deltamethrin. The entomatic tests revealed that the nanocomposite coating was the most effective for preventing the wheat weevil attack, with no damages detected on the samples and high mortality of the insects due to hunger. The approach proposed here could be successfully extended to other art objects (e.g., museum collections) susceptible to insect attacks. [ABSTRACT FROM AUTHOR]

This paper addresses the question of whether auction guarantees change the bidding environment and whether they cause a change in price once the value of an item is taken into account. We analyze both the cases of third-party guarantees and in-house guarantees. We use two datasets: one of Christie’s and Sotheby’s Contemporary and Impressionist Evening Sales from January 2010 to February 2012 and another larger dataset consisting of all items auctioned at Christie's from 2001 to May 2011. While more expensive items are more likely to have guarantees, we find little empirical evidence to suggest an effect on price from the guarantee itself once the value of the item is taken into account. We thank Chunrong Ai, Orley Ashenfelter, Stephen Brown, Geraldine David, Paul Milgrom, Kim Oosterlinck, and Rachel Pownall for valued comments and Adam Narkiewicz, Alberto Ortega, and Wenche Wang for assistance in data collection. [ABSTRACT FROM AUTHOR]

The goal of this paper is to evaluate the potential of reflection infrared spectroscopy in discriminating among different binding media in 20th century painting, with relation to distortion effects due to the mixing of surface and volume reflection and potential overlaps by pigment absorption bands. The study was carried out analyzing the reflection infrared properties of modern paint reconstructions including acrylic emulsion, polyvinyl acetate resin, oil-modified alkyd resin and two traditional media (drying oil and proteinaceous tempera) in mixture with a number of pigments selected for their absorption bands and their potential overlaps in the mid and near-infrared regions. Specific spectral markers were determined for each binding medium and then successfully exploited for the interpretation/classification of non-invasive reflection infrared spectra recorded in situ on eleven paintings of the second half of the twentieth century. [ABSTRACT FROM AUTHOR]

In order to identify the best practices and guidelines for the conservation of contemporary artworks, innovative approaches are needed, based on a monitoring campaign to assess the rate of alteration/decay of the objects placed outdoors. In this project, which is still in its first stage, the evolution in time of characteristic parameters is being used to establish thresholds for maintenance or restoration of three installations in the monumental garden of the “Fattoria di Celle”, located in Santomato (Pistoia, Italy). This garden hosts the Gori collection of 43 site-specific artworks created by contemporary artists. The three installations selected have different material compositions: bronze, stone and mortar painted with acrylic colors and glass . Each installation had its own conservation problems related to the constituent materials, together with the important impact of outdoor exposure and location. After a preliminary investigation, the major issues and risks for each artwork were identified and the monitoring campaign was started. Portable diagnostic tools and micro-sampling were used to monitor the parameters chosen. One year into the campaign, the preliminary diagnostic documentation has been realized, mainly for the bronze artistic object. Furthermore, the initial guidelines for monitoring campaigns have been defined. [ABSTRACT FROM AUTHOR]

Engaging students in higher order thinking such as evaluation and analysis has been recognized as being an important strategy for helping them develop knowledge and skills, in particular, in creativeness-oriented learning activities such as artwork design. In this paper, an interactive peer-assessment criteria development approach is proposed to help students develop assessment criteria, learn from viewing peers' work, and make reflections in artwork design activities using mobile devices. To evaluate the effectiveness of the proposed approach, an experiment was conducted in an elementary school art course. A total of 103 students participating in the experiment were assigned to an experimental group and a control group. The students in the experimental group learned with the proposed approach, while those in the control group learned with the conventional peer assessment approach. From the experimental results, it was found that the proposed approach significantly improved the students' learning achievement, learning motivation and meta-cognitive awareness, suggesting the effectiveness of engaging students in assessment criteria development in an interactive manner. [ABSTRACT FROM AUTHOR]

One way to increase art appreciation is to create congruency between the actions performed by the artist and the actions performed by the viewer. Leder, Bar, and Topolinski (2012) successfully created such a link by asking participants to make either stroking or stippling motions while viewing stroke-style and pointillist-style paintings. We carried out a direct replication of Leder et al. (2012) in Experiment 1 but failed to reproduce their results. In Experiment 2, we achieved the desired cross-over interaction between image and action but only when the relationship was made more transparent. Experiment 3 demonstrated that this effect requires a motor component and cannot be reproduced by simply hearing the sounds associated with drawing production. Experiment 4 investigated whether either an external manipulation or a self-report measure of awareness of the image–action match modulated the liking ratings, in addition to artwork familiarity and participants’ own hypotheses regarding the direction of the image–action effect. Participants who predicted that congruent relationships between what they saw and what they did would increase liking showed enhanced congruency effects. The links between historical production and contemporary exposure to art may then be an overt rather than covert process. [ABSTRACT FROM AUTHOR]

Traditionally, artworks are seen as autonomous objects that stand (or should stand) on their own. However, at least since the emergence of Conceptual Art in the 1920s and Pop Art in the 1960s, art lacks any distinctive perceptual features that define it as such. Art, therefore, cannot be defined without reference to its context. Some studies have shown that context affects the evaluation of artworks, and that specific contexts (street for graffiti art, museum for modern art) elicit specific effects (Gartus & Leder, 2014). However, it is yet unclear how context changes perception and appreciation processes. In our study we measured eye-movements while participants (64 psychology undergraduates, 48% women) perceived and evaluated beauty, interest, emotional valence, as well as perceived style for modern art and graffiti art embedded into either museum or street contexts. For modern art, beauty and interest ratings were higher in a museum than in a street context, but context made no difference for the ratings of graffiti art. Importantly, we also found an interaction of context and individual interest in graffiti for beauty and interest ratings, as well as for number of fixations. Analyses of eye-movements also revealed that viewing times were in general significantly longer in museum than in street contexts. We conclude that context can have an important influence on aesthetic appreciation. However, some effects depend also on the style of the artworks and the individual art interests of the viewers. [ABSTRACT FROM AUTHOR]

The Diagnostic Drawing Series (DDS) was used to investigate differences between non-hospitalized adult and adolescent artwork. Using the complete DDS Revised Rating Guide (Cohen, 1994. The diagnostic drawing series rating guide .), a control group of 60 adult DDSs were compared to the DDSs of to 60 adolescents, ages 13–17. A chi-square analysis indicated statistically significant ( p < .05) findings. The most significant findings for adolescent images included: more single image and unusual placement in picture one; angular/curvilinear mix and geometric/angular lines in picture two; line only drawings and disintegration in picture three. This pioneering research begins to set the norm towards standardizing healthy adolescent artwork using the DDS. [ABSTRACT FROM AUTHOR]

The position of an item influences its evaluation, with research consistently finding that items occupying central locations are preferred and have a higher subjective value. The current study investigated whether this centre-stage effect (CSE) is a result of bottom-up gaze allocation to the central item, and whether it is affected by item valence. Participants ( n = 50) were presented with three images of artistic paintings in a row and asked to choose the image they preferred. Eye movements were recorded for a subset of participants ( n = 22). On each trial the three artworks were either similar but different, or were identical and with positive valence, or were identical and with negative valence. The results showed a centre-stage effect, with artworks in the centre of the row preferred, but only when they were identical and of positive valence. Significantly greater gaze allocation to the central and left artwork was not mirrored by equivalent increases in preference choices. Regression analyses showed that when the artworks were positive and identical the participants' last fixation predicted preference for the central art-work, whereas the fixation duration predicted preference if the images were different. Overall the result showed that item valence, rather than level of gaze allocation, influences the CSE, which is incompatible with the bottom-up gaze explanation. We propose that the centre stage heuristic, which specifies that the best items are in the middle, is able to explain these findings and the centre-stage effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] The nature of the mind-mindedness construct was investigated. [•] Adults’ mind-minded descriptions of significant others correlate positively. [•] Mind-minded descriptions of significant others are unrelated to those of famous people/paintings. [•] Mind-mindedness appears not to be a trait-like quality. [•] These findings may help inform our understanding of theory of mind in adulthood. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional (3D) digital preservation aims at generating 3D models of objects that have cultural or scientific value. It allows realistic visualization of objects through virtual museums or scientific applications, and the restoration of the preserved object in case of natural wear or accidents. This work contributes to this research area by presenting a method to improve color texture quality of 3D models obtained from color and depth images of a laser scanner. Although this device offers precise depth information, the resulting color information is still poor and limits the generation of realistic textures. Our approach is to capture photographs of the object with a high-resolution digital camera and use them to generate a new color texture for the 3D model. Our work proposes a practical technique, easy to replicate, to generate high quality textures for 3D models from photographs. The method is composed by three main steps: (1) calibration of the image acquisition devices; (2) data acquisition; and (3) texture generation. In this paper, we detail our color texture generation method and apply it on the digital preservation of many artworks made by native Brazilians (indians) from the Wauja and Karaja communities. These indigenous communities are acknowledged as great ceramic artists, each bearing their own main themes, using a very rich symbolism in their paintings. Their artworks represent important aspects of the native South American culture and their digital preservation is motivated by three main reasons: (1) their fragility; (2) the paintings loose their original appearance with time; and (3) the possibility of extinction of these communities. We present several results of preserved artworks with enhanced quality realistic texture maps. Also, we present a methodology to analyze the quality and accuracy of texture maps. The resulting 3D models can be visualized through a tool we developed to support the virtual exhibit of 3D preserved heritage. [Copyright &y& Elsevier]

Abstract: An accurate characterisation of the organic dyes used in artworks, especially those made of paper, is an important factor in designing safe conservation treatments. In the case of synthetic organic dyes used in modern works of art, for example, one frequently encountered difficulty is that some of these dyes are not still commercially available. Recognizing this problem, the authors of this paper present the results of an analysis of UV–Vis–NIR fibre optic reflectance spectra of 82 samples of dyed paper prepared with 41 dyes. The samples come from a historic book, The Dyeing of Paper in the Pulp, which was published by Interessen-Gemeinschaft (I.G.) Farbenindustrie in 1925. The dyes used in the paper pulp belong to the azo compounds, acridine, anthraquinone, azine, diphenylmethane, indigoid, methine, nitro, quinoline, thiazine, triphenylmethane, sulphur and xanthene classes. [Copyright &y& Elsevier]

In a recent technical note in this Journal, de Faria et al., 2017 [1] reported the Raman spectrum of authentic Indian yellow artists' pigment, correcting a decades old reference spectrum that has led to the misidentification of this pigment in artworks that actually contained tartrazine yellow. The present communication provides additional information and corrects important experimental details mentioned by de Faria et al. that should lead to further identifications of the authentic pigment in artworks. Despite their claim that the analysis of this naturally fluorescent colorant is only possible with Fourier transform (FT) instruments, the ready characterization of two authentic samples of historic Indian yellow pigment is demonstrated here using commonly available visible and near-infrared excitation sources on a dispersive Raman microspectrometer. To highlight the importance of the proper identification of dyes and colorants, the authentication and art historical implications of previous literature reports that have misidentified Indian yellow on historic documents are more thoroughly discussed here from a forensic science point of view. The numerous modern pigments that are sold as imitation Indian yellow are addressed and analyzed, allowing the ready noninvasive detection of anachronistic colorants in attempted forgeries. Finally, this unusual pigment is positively identified for the first time using non-invasive dispersive Raman microspectroscopy on a historic object of uncertain date, a highly decorative manuscript from the Indian subcontinent. [ABSTRACT FROM AUTHOR]