Painting the Palace of Apries I: ancient binding media and coatings of the reliefs from the Palace of Apries, Lower Egypt

This study gives an account of the organic components (binders and coatings) found in the polychromy of some fragmented architectural reliefs from the Palace of Apries in Memphis, Egypt (26th Dynasty, ca. 589-568 BCE). A column capital and five relief fragments from the collections of the Ny Carlsberg Glyptotek in Copenhagen were chosen for examination, selected because of their well-preserved polychromy. Samples from the fragments were first investigated using Fourier transform infrared (FTIR) spectroscopy to screen for the presence of organic materials and to identify the chemical family to which these materials belong (proteinaceous, polysaccharides or lipid). Only the samples showing the potential presence of organic binder residues were further investigated using gas chromatography with mass spectrometry detection (GC-MS) targeting the analysis towards the detection and identification of compounds belonging to the chemical families identified by FTIR. The detection of polysaccharides in the paint layers on the capital and on two of the fragments indicates the use of plant gums as binding media. The interpretation of the sugar profiles was not straightforward so botanical classification was only possible for one fragment where the results of analysis seem to point to gum arabic. The sample from the same fragment was found to contain animal glue and a second protein material (possibly egg). While the presence of animal glue is probably ascribable to the binder used for the ground layer, the second protein indicates that either the paint layer was bound in a mixture of different binding materials or that the paint layer, bound in a plant gum, was then coated with a proteinaceous material. The surface of two of the investigated samples was partially covered by translucent waxy materials that were identified as a synthetic wax (applied during old conservation treatments) and as beeswax, respectively. It is possible that the beeswax is of ancient origin, selectively applied on yellow areas in order to create a certain glossiness or highlight specific elements

Violin varnishes: microstructure and nanomechanical analysis

The aim of the current work is twofold: to demonstrate the application of in situ non-invasive imaging by portable atomic force microscopy (AFM) on the surfaces of a violin and to integrate compositional and mechanical analysis at the nano scale level on model samples of varnished wood. These samples were prepared according to traditional recipes by an Italian lutemaker family well practised in the art. Samples of oil and spirit-based varnishes on maple wood, naturally and accelerated light aged, were studied. AFM was used to measure the nanomechanical properties of the model samples and established that the spirit-based varnish was stiffer than the oil-based. Synchrotron radiation micro- Fourier Transform Infra-red analysis of the layer structure revealed that stiffer spirit-based varnish showed less penetration into the wood than the oil-based. Further PeakForce Quantitative Nanomechanical Mapping (QNM) demonstrated a difference in adhesion values between the oil- and spirit-based sample

Comparison of uniportal robotic-assisted thoracic surgery pulmonary anatomic resections with multiport robotic-assisted thoracic surgery: a multicenter study of the European experience

Background: Robotic-assisted thoracic surgery (RATS) has seen increasing interest in the last few years, with most procedures primarily being performed in the conventional multiport manner. Our team has developed a new approach that has the potential to convert surgeons from uniportal video-assisted thoracic surgery (VATS) or open surgery to robotic-assisted surgery, uniportal-RATS (U-RATS). We aimed to evaluate the outcomes of one single incision, uniportal robotic-assisted thoracic surgery (U-RATS) against standard multiport RATS (M-RATS) with regards to safety, feasibility, surgical technique, immediate oncological result, postoperative recovery, and 30-day follow-up morbidity and mortality. Methods: We performed a large retrospective multi-institutional review of our prospectively curated database, including 101 consecutive U-RATS procedures performed from September 2021 to October 2022, in the European centers that our main surgeon operates in. We compared these cases to 101 consecutive M-RATS cases done by our colleagues in Barcelona between 2019 to 2022. Results: Both patient groups were similar with respect to demographics, smoking status and tumor size, but were significantly younger in the U-RATS group [M-RATS =69 (range, 39-81) years; U-RATS =63 years (range, 19-82) years; P<0.0001]. Most patients in both operative groups underwent resection of a primary non-small cell lung cancer (NSCLC) [M-RATS 96/101 (95%); U-RATS =60/101 (59%); P<0.0001]. The main type of anatomic resection was lobectomy for the multiport group, and segmentectomy for the U-RATS group. In the M-RATS group, only one anatomical segmentectomy was performed, while the U-RATS group had twenty-four (24%) segmentectomies (P=0.0006). All M-RATS and U-RATS surgical specimens had negative resection margins (R0) and contained an equivalent median number of lymph nodes available for pathologic analysis [M-RATS =11 (range, 5-54); U-RATS =15 (range, 0-41); P=0.87]. Conversion rate to thoracotomy was zero in the U-RATS group and low in M-RATS [M-RATS =2/101 (2%); U-RATS =0/101; P=0.19]. Median operative time was also statistically different [M-RATS =150 (range, 60-300) minutes; U-RATS =136 (range, 30-308) minutes; P=0.0001]. Median length of stay was significantly lower in U-RATS group at four days [M-RATS =5 (range, 2-31) days; U-RATS =4 (range, 1-18) days; P<0.0001]. Rate of complications and 30-day mortality was low in both groups. Conclusions: U-RATS is feasible and safe for anatomic lung resections and comparable to the multiport conventional approach regarding surgical outcomes. Given the similarity of the technique to uniportal VATS, it presents the potential to convert minimally invasive thoracic surgeons to a robotic-assisted approach.info:eu-repo/semantics/publishedVersio

Ancient encaustic: An experimental exploration of technology, ageing behaviour and approaches to analytical investigation

The composition of the ancient wax-based painting technique known as encaustic has long been the subject of debate. Ancient sources provide few details of the technology, and modern understanding of the medium is restricted to theoretical interpretation and experimental observation. In this multi-analytical collaborative study, a number of analytical approaches were used to investigate the physical and molecular properties of a range of experimentally prepared encaustic paints before and after ageing. Analysis using gas chromatography mass spectrometry, Fourier transform infrared spectroscopy (invasive and non-invasive), X-ray diffraction and thermogravimetric analysis demonstrated how differences in the technology of production alter the properties and composition of the medium and showed how these are modified by the addition of pigment and the effects of ageing. Comparison of results from the different analytical techniques highlights the benefit of an integrated analytical approach to the analysis of ancient encaustic paints and the fundamental importance of insights from invasive study to evaluating the results of non-invasive analysis

Two-step analytical procedure for the characterization and quantification of metal soaps and resinates in paint samples

Metal soaps and resinates are known to be spontaneously formed in artistic paintings, as a product of the reaction between aliphatic and terpenoid acids released by hydrolysis and oxidation of the organic media and certain cations contained in some inorganic pigments. In this paper we present an optimization and the validation of a GC/MS method for the qualitative and quantitative analysis of mixtures of terpenoid acids and aliphatic mono and dicarboxylic acids and metal carboxylates of terpenoid and aliphatic mono and dicarboxylic acids in the same paint microsample. This is based on a two-step analytical approach entailing the subsequent use of two silylating agents, N,O-bis(trimethylsilyl)trifluoroacetamide for the analysis of free acids and metal carboxylates, and 1,1,1,3,3,3-hexamethyldisilazane for the analysis of free acids. The application of this approach is possible because of the good stability at room temperature of the TMS derivatives of aliphatic and terpenoid species, characterized by high boiling points and relatively low vapour pressures. The method was then applied to the characterization of samples collected from two reference paint layers aged for 20&nbsp;years, a paint sample taken from a pulpit, and sample of the varnish coating of a wooden writing desk, both from the second half of the seventeenth century