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Copyright of Studies in Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Paper Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Records from a popular series at The National Archives were found to bear warning labels that they have been bound using a 'poisonous insecticidal solution'. Research into historic sources suggested that the agents used by bookbinders in the early twentieth century were mercuric chloride, copper sulphate, and beechwood creosote; these may have been replaced by organochlorine pesticides (OCPs) such as dichlorodiphenyltrichloroethane (DDT) mid-century. Analysis by X-ray fluorescence (XRF) spectroscopy confirmed the presence of mercury in labelled, bound items. A number of OCPs were detected using gas chromatography/mass spectrometry (GCMS) including DDT, gamma-hexachlorocyclohexane (Lindane, γ-HCH), Dieldrin, pentachlorophenol (PCP), dichlorodiphenyldichloroethylene (DDE), and 1-chloronaphthalene (1-CP). Tests confirmed the presence of these agents on all items tested regardless of format (e.g. tagged files and bound volumes) or period of creation, suggesting the OCPs were introduced to the items after the binding process. An occupational hygienist (OH) consultancy was engaged to carry out in-situ air monitoring during production, digitisation, and general handling of the items. Risk assessments were developed based on the results, allowing readers and staff to once again access the collection with safety measures including the use of personal protective equipment (PPE). [ABSTRACT FROM AUTHOR]

Copyright of Journal of the American Institute for Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Beeswax is a product of honeybees (Apis mellifera) and has been used extensively through time, especially as the primary component in medieval sealing wax for authenticating millions of documents. Today, these seals form large collections which, along with the historical information in the documents that the seals are attached to, could be a potential biomolecular archive for honeybees. Here, we investigate the possibility of obtaining biological information from medieval wax seals by performing a palynological and shotgun metagenomic analysis on eight medieval wax seal fragments. Our palynological results show that some pollen and fungal spores remain in the seals, albeit very little. Only one out of eight samples yielded enough DNA for sequencing. Moreover, only minor parts of the DNA reads could be taxonomically identified and were identified as plant and fungal DNA. These results demonstrate some potential for using wax seals as biological archives, but most importantly provides a framework for future studies, in addition to understanding further the degradation of seals as cultural heritage objects. We emphasize that future analyses should focus on other methodologies to retrieve data for historical context or alternatively improve molecular methods and screen sample collections broadly. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Institute of Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes the methodology and practice-based research underpinning the development of a successful cleaning strategy for Eva Hesse's sculpture Addendum (1967, Tate Collection T02394). Research strands included: technical and art historical investigations to determine the materials and construction of the work of art and to define the aims of the conservation treatment; the production, soiling and accelerated ageing of mock-up samples using contemporary equivalent materials; and the systematic, iterative evaluation of soiling removal systems, which were further refined for appropriate use on the work of art. The comparative cleaning system evaluation was employed to determine options which offered optimal soiling removal efficacy and posed minimal risk to the work of art. Newly developed Nanorestore Gel® Peggy series (i.e. polyvinyl alcohol (PVA) and polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP)-based hydrogels), designed for the cleaning of modern and contemporary art, were evaluated with a range of other gels, emulsifiers and cosmetic sponges and assessed through a combination of empirical observation, microscopy and spectroscopic techniques. Promising options, combined with tailored aqueous phases derived from trials on mock-up samples, were then evaluated on discreet areas of the sculpture. After extensive testing, the top papier mâché section of Addendum was surface cleaned using an aqueous solution applied with cosmetic sponges, and the ropes were surface cleaned using a modified version of Nanorestore Gel® Peggy 5 (PVA/PVP) loaded with a tailored aqueous solution. The optimisation of this hydrogel, combined with the extensive supporting research, enabled the successful, low-risk, conservation treatment of Addendum for the first time since acquisition. [ABSTRACT FROM AUTHOR]

Roy Lichtenstein's Whaam! (1963) is an iconic artwork in Tate's collection (T00897). Over the past 50 years, the painting has been on almost continuous display and had accrued a layer of deposited soiling, which resulted in the dampening of Lichtenstein's vibrant colours and the masking of numerous subtleties across the painting surface. This paper outlines the design and execution of an optimal soiling removal strategy for this challenging work; utilising collaborative, practice-based research. The conservation treatment employed was derived through an iterative process that reflected and supported the conservation decision-making process. The research strands included: technical and art historical investigations to determine the materials and construction of Whaam! and to define the aims of the conservation treatment; preparation of accelerated aged and artificially soiled test (mock-up) paint samples based on contemporary equivalent materials and a comparative evaluation of a range of established and novel soil-removal systems, followed by further tailoring for use on the work of art. The range of cleaning systems evaluated included free-solvents, gels and emulsifiers; which were documented using star diagrams, digital microscopy and infrared spectroscopy. After a rigorous process of assessment and refinement, the strategy taken forward to Whaam! included the use of a polyvinyl alcohol-based polymeric hydrogel (Nanorestore Gel® Peggy 6), uploaded with tailored aqueous solutions. This process facilitated a low risk, controlled and even-removal of the soiling layer, enabling the successful treatment of this sensitive painting for the first time in the painting's history. [ABSTRACT FROM AUTHOR]

The combination of the macrocyclic hosts p‐sulfonatocalix[4]arene and cucurbit[7]uril with the fluorescent dyes lucigenin and berberine affords two label‐free enzyme assays for the detection of kinase and phosphatase activity by fluorescence monitoring. In contrast to established assays, no substrate labeling is required. Since phosphorylation is one of the most important regulatory mechanisms in biological signal transduction, the assays should be useful for identification of inhibitors and activators in high‐throughput screening (HTS) format for drug discovery. [ABSTRACT FROM AUTHOR]

Moisture is a driving factor in the long-term mechanical deterioration of canvas paintings, as well as for a number of physico--chemical degradation processes. Since the 1990s a number of publications have addressed the equilibrium hygroscopic uptake and the hygro-mechanical deformation of linen canvas, oil paint, animal glue, and ground paint. In order to visualise and quantify the dynamic behaviour of these materials combined in a painting mock-up or reconstruction, we have performed custom-designed experiments with neutron radiography and nuclear magnetic resonance (NMR) imaging. This paper reports how both techniques were used to obtain spatially and temporally resolved information on moisture content, during alternate exposure to high and low relative humidity, or in contact with liquids of varying water activities. We observed how the canvas, which is the dominant component in terms of volumetric moisture uptake, absorbs and dries rapidly, and, due to its low vapour resistance, allows for vapour transfer towards the ground layer. Moisture desorption was generally found to be faster than absorption. The presence of sizing glue leads to a local increase of moisture content. It was observed that lining a painting with an extra canvas results in a damping effect: i.e. absorption and drying are significantly slowed down. The results obtained by NMR are complementary to neutron radiography in that they allow accurate monitoring of water ingress in contact with a liquid reservoir. Quantitative results are in good agreement with adsorption isotherms. The findings can be used for risk analysis of paintings exposed to changing micro-climates or subjected to conservation treatments using water. Future studies addressing moisture-driven deformation of paintings can make use of the proposed experimental techniques. [ABSTRACT FROM AUTHOR]

A versatile gel-like system for the treatment of art has been prepared from partially hydrolyzed poly(vinyl acetate), borax, and large fractions of ethanol, isopropyl alcohol, n-propyl alcohol, and acetone. Variables such as the concentrations of the two gelating components, the degree of hydrolysis and molecular weight of the polymer, and the type of liquid gelated were investigated to establish formulations of gels with physical and chemical properties that are best suited for specific applications. The gels were designed to have an elastic character that allows them to conform to the topography of complex surfaces and be removed with ease by being lifted from the surface. Results from fluorescence studies demonstrated that the solvent is constrained within the area of the gel, allowing for localized treatment. Polymer and boron residues were not detected after cleaning tests on acrylic and dammar test paint-outs, and on two oil paintings with degraded surface coatings. The efficacy of the cleaning systems was determined visually. Studies of the materials removed during treatments showed that the gels appear to act by softening the coating surface while typically a pass with a solvent-dampened swab after gel treatment removes the softened coating. Two case studies and notes on other applications of the gels are described; recipes and preparation procedures are included. [ABSTRACT FROM AUTHOR]

Converting single-stranded viral RNA into double stranded DNA for integration is an essential step in HIV-1 replication. Initial polymerization of minus-strand DNA is primed from a host derived tRNA, whereas subsequent plus-strand synthesis requires viral primers derived from the 3′ and central polypurine tracts (3′ and cPPTs). The 5′ and 3′ termini of these conserved RNA sequence elements are precisely cleaved by RT-associated RNase H to generate specific primers that are used to initiate plus-strand DNA synthesis. In this study, siRNA wad used to produce a replicative HIV-1 variant contained G(-1)A and T(-16)A substitutions within/adjacent to the 3′PPT sequence. Introducing either or both mutations into the 3′PPT region or only the G(-1)A substitution in the cPPT region of NL4-3 produced infectious virus with decreased fitness relative to the wild-type virus. In contrast, introducing the T(-16)A or both mutations into the cPPT rendered the virus(es) incapable of replication, most likely due to the F185L integrase mutation produced by this nucleotide substitution. Finally, the effects of G(-1)A and T(-16)A mutations on cleavage of the 3′PPT were examined using an in vitro RNase H cleavage assay. Substrate containing both mutations was mis-cleaved to a greater extent than either wild-type substrate or substrate containing the T(-16)A mutation alone, which is consistent with the observed effects of the equivalent nucleotide substitutions on the replication fitness of NL4-3 virus. In conclusion, siRNA targeting of the HIV-1 3′PPT region can substantially suppress virus replication, and this selective pressure can be used to generate infectious virus containing mutations within or near the HIV-1 PPT. Moreover, in-depth analysis of the resistance mutations demonstrates that although virus containing a G(-1)A mutation within the 3′PPT is capable of replication, this nucleotide substitution shifts the 3′-terminal cleavage site in the 3′PPT by one nucleotide (nt) and significantly reduces viral fitness. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of aqueous polymer gel as a means of controlling solvent diffusion and reducing mechanical damage during treatment of Poly (methyl methacrylate) PMMA. Topics discussed include ability of Gellan gels to partially remove artificial soil from the surface of PMMA samples with propanol gel removing more soil than hydrogel, gravimetric analysis of PMMA sample after application of Polyvinyl acetate (PVAc)/Borax gel, and removal of sodium dodecyl sulfate (SDS) monolayer from the surface after applying PVAc/Borax hydrogel. Also included is a graph showing sum frequency generation (SFG) spectra for PMMA films and a conclusion that Gellan gels were more effective in removing artificial soil than PVA gels.

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Background: Neospora caninum is an intracellular obligate apicomplexan parasite responsible for multisystemic lesions in dogs. Being definitive hosts and reservoirs, dogs excrete environmentally resistant oocysts. Breeding bitches represent a susceptible dog group and infected bitches may spread this parasite through transplacental transmission. Results: A total of 218 serum samples of German breeding bitches were collected to determine the presence of N. caninum. Antibodies were detected in 16 (7.33%) bitches using a commercial indirect enzyme-linked immunosorbent assay (ELISA). Immunoblotting analysis confirmed all seropositive samples detected by ELISA, proving that the animals were infected with N. caninum. The owners were interviewed regarding breed, age, environment, type, vaccine status, feeding habits and the presence of reproductive disorders. Seropositive animals were between the ages of two to seven years; three of them were kept in kennels while the others were household dogs, one of which was additionally a hunting dog. Owners of four seropositive bitches reported one gestation, while multiple pregnancies had been recorded for the other twelve bitches. Fourteen bitches were regularly vaccinated and six were fed with fresh raw meat. Conclusions: Although the results confirmed a low incidence of N. caninum seropositive German breeding bitches, further epidemiological and surveillance studies are required to complement our findings regarding the current situation of neosporosis in this specific canine population of Germany. [ABSTRACT FROM AUTHOR]