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Since the introduction of the Oddy test in 1973, many museums and cultural institutions have put the method in use, developing their own versions and protocols. Currently the 3-in-1 version, temperature at 60 ºC and 2 g of tested material are set as common practice; however, other variables of the test are not standardized. The purpose of this study is to examine current versions of the Oddy test, to identify differences in the results derived from variations in the procedures, and ultimately raising awareness within the conservation community to work together towards a standardized protocol. In this article, we review the available information on the methodological differences in Oddy test protocols published in the literature related to glassware cleaning, coupon preparation, reaction vessel setup and rating of materials. Based on the review, and to highlight the many variables that could affect the results of the test, seven European cultural institutions working under the H2020 IPERION HS project performed a comparative 3-in-1 Oddy test by blindly evaluating the same ten materials. Each institution used its own test methodology but some guidelines were advised: (1) Detergents as a cleaning procedure for glassware, (2) P600 sandpaper or micromesh pad close to 1500 to prepare metal coupons and (3) 1:100 as water–air ratio. Despite this, differences between institutions’ results were still observed. Some of them are due to the differences in the coupons preparation, either in the sanding pattern or in the edge area. In order to separate the contribution of the experimental setup and the subjectivity of the evaluation in the discrepancies, coupons from all institutions have been rated by a single team of judges with experience in the Oddy Test. Results show that differences in the evaluation criteria play a relevant role in the discrepancies of the results, especially for institutions with less experience in the test. These results highlight the need to further standardize the methodology and criteria for visual assessment. Nevertheless, the Oddy test has been found to be reliable for the identification of materials that produce emissions hazardous for the conservation of cultural assets.

Some of the most overlooked valuation systems in current literature are those based on expert algorithms. Yet these algorithms can form the basis of a good estimation of the value of real estate since they allow simple computational methods that use big data to be integrated with the appraiser’ own knowledge of the situation. The main usefulness of the methodology is an ongoing mortgage risk appraisal for banking institutions. The current expert algorithms based on the sales comparison approach use the arithmetic mean of the comparable prices. But this mean gives equal importance to all neighbouring dwellings instead of giving more importance to those dwellings which are more similar and are nearer to the target dwelling. Improving the classical arithmetic mean or the more robust median, this article proposes a computer-assisted expert algorithm which includes a weighted estimator able to consider the differences in characteristics compared to similar properties and their relative locations. It allows to estimate, in a simple and rapid way using objective criteria, the value of any residential property in Spain. The results show good fit for large cities in terms of the usual error margins while improving the results with regards to smaller cities. In all cases, in terms of mean absolute percentage error, the weighted estimator improves the arithmetic mean or median results.

The development of new alternatives for the protection of metallic heritage aims to improve the performance of the coatings used in recent decades. For this purpose, the performance of three novel or poorly explored coatings in this field of study has been evaluated: Owatrol Oil, TiO2-modified Paraloid B-72 and a hybrid of poly(2-ethyl-2-oxazoline), PEOX and poly(4-hydroxy styrene), PHS as a self-healing coating. These have been compared with coatings widely used in conservation such as: Paraloid B-72, Incralac and microcrystalline wax C80. The coatings were evaluated after accelerated ageing in terms of aesthetic changes (visual observation under stereomicroscope and colour measurements), protective ability (electrochemical impedance spectroscopy) and chemical stability (FTIR). After 500 h of exposure to Xenon-arc lamp, it was observed how the addition of TiO2to Paraloid B-72 partially reduces photo-oxidation of the polymer, but at the same time harms the protective ability due to the appearance of defects. The self-healing coating is quite stable and can also regenerates superficial scratches of about 100 µm if subjected to 90% RH. On the other side, Owatrol demonstrated a very poor performance. These advantages and disadvantages in their use have been compared with those of B-72, Incralac and C80 microcrystalline wax, identifying in which cases their application for protection on scientific-technical artefacts may be feasible.

The lack of a standardised methodology for the application of coatings on heritage metals can lead to non-comparable results. A careful and meaningful study requires considering the different application variables involved, especially in the preparation of the coupons. In this work, the effect that these application variables can have on the protective capacity of the coatings used has been studied. The influence of the thickness, number of layers and drying time (between layers and final) of Paraloid B-72, C80 microcrystalline wax and Incralac has been evaluated. Coatings have been applied on bare steel coupons, thickness measured with an induction probe, and subject to artificial ageing on UV light/water condensation cycles. The performance of the coatings has been studied by visual inspection and electrochemical impedance spectroscopy (EIS). Morphology of the layers has been characterised by optical microscopy and the composition of the corrosion products by Raman spectroscopy. Results show that the number of layers is not always proportional to the final thickness of the coating, and that drying time is a critical factor affecting the thickness and the protective properties of the coatings. After accelerated ageing, some coatings that had been left to dry for 14 days have a much better protective capacity than those that were left to dry for less time. Without taking into account these factors, performance measured can be wrong and comparison between materials misleading.

BNT162b2 (BioNTech and Pfizer) is a nucleoside-modified mRNA vaccine that provides protection against SARS-CoV-2 infection and is generally well tolerated. However, data about its efficacy, immunogenicity and safety in people of old age or with underlying chronic conditions are scarce.

Colour changes of cultural heritage objects can be related with degradation of materials, thus a proper colour monitoring system can be used to detect conservation problems. With this purpose, a monitoring methodology for cultural heritage preventive conservation based on tailored colour reference charts and image analysis is proposed.

The corrosion of a copper electrode in a 5% HCl solution is analyzed using impedance data recorded at the corrosion potential. A straight line is observed at high frequencies, attributed to a diffusion process in the film covering the copper surface. This line curls down towards the real axis at intermediate frequencies, drawing a depressed quarter lemmiscate. The impedance plot is completed by a second straight line at very low frequencies.

The copper corrosion products originated by the action of formic, acetic and propionic acid vapors at a 100% relative humidity were studied for a period of 21 days. Five formic, acetic and propionic vapor concentrations (10, 50, 100, 200 and 300 ppm) were tested. The corrosion-product layers were characterized using electrochemical methods. Some of the compounds identified were: cuprite (Cu2O), for the three acids; cupric hydroxide monohydrate (Cu(OH)2*H2O) and copper formate tetrahydrate (Cu(HCOO)2*4H2O), for formic acid; copper acetate dihydrate (Cu(CH3COO)2*2H2O) and copper hydroxide acetate dihydrate (Cu4(OH)(CH3COO)7*2H2O), for acetic acid; and copper propionate (Cu4(OH)(CH3CH2COO)7*2H2O) for propionic acid.

Abstract: The possibility of using in vitro shoot apex culture to evaluate salt tolerance of cultivated (Lycopersicon esculentum Mill.) and wild (Lycopersicon pennellii (Correll) D'Arcy) tomato species was determined and related to the response obtained by callus culture. Both apices and calluses were grown on media supplemented with 0, 35, 70, 105, 140, 175 and 210 mM NaCl, and growth and physiological traits were determined. Most apices of L. esculentum did not develop roots from low NaCl levels, whereas the apices of L. pennellii were able to develop roots at the different salt levels. This different degree of salt tolerance between L. esculentum and L. pennellii was not, however, clearly shown on the basis of the shoot growth of the plantlets. The callus response was similar to that shown by the rooting parameters, as callus growth in response to increased salinity was much greater in L. pennellii than in the tomato cultivar. K+decreased more and proline accumulated less with salinity in shoots of L. esculentum compared to L. pennellii, whereas the opposite response was obtained in calluses. The results obtained in this study suggest that rooting parameters are the most useful traits for rapid evaluation and screening of tomato species and segregating populations through in vitro shoot apex culture.

Summary. If in vitro culture is to be used for evaluating the salt tolerance of tomato hybrids and segregant populations in a breeding programme, it is previously necessary to get quick and reliable traits. In this work, growth and physiological responses to salinity of two interspecific hybrids between the cultivated tomato ( Lycopersicon esculentum Mill) and its wild salt-tolerant species L. pennellii are compared to those of their parents. The leaf callus of the first subculture was grown on media amended with 0, 35, 70, 105, 140, 175 and 210 mM NaCl for 40 days. Relative fresh weight growth of callus in response to increased salinity in the culture medium was much greater in L. pennellii than in the tomato cultivars, and greater in the hybrids than in the wild species. Moreover, the different salt tolerance degree of hybrids was related to that of female parents. At high salt levels, only Cl – accumulation was higher in L. pennellii than in tomato cultivars, whereas in the hybrids both Cl – and Na + accumulation were higher than in their parents. Proline increased with salinity in the callus of all genotypes; these increases were much higher in the tomato cultivars than in L. pennellii, and the hybrids showed a similar response to that of the wild species. Salt-treated callus of the tomato cultivars showed significant increases in valine, isoleucine and leucine contents compared to control callus tissue. In contrast, these amino acids in callus tissues of the wild species and hybrids showed a tendency to decrease with increasing salinity.

The corrosion of a copper electrode in a 5% HCl solution is analyzed using impedance data recorded at the corrosion potential. A straight line is observed at high frequencies, attributed to a diffusion process in the film covering the copper surface. This line curls down towards the real axis at intermediate frequencies, drawing a depressed quarter lemmiscate. The impedance plot is completed by a second straight line at very low frequencies.

The copper corrosion products originated by the action of formic, acetic and propionic acid vapors at a 100% relative humidity were studied for a period of 21 days. Five formic, acetic and propionic vapor concentrations (10, 50, 100, 200 and 300 ppm) were tested. The corrosion-product layers were characterized using electrochemical methods. Some of the compounds identified were: cuprite (Cu2O), for the three acids; cupric hydroxide monohydrate (Cu(OH)2•H2O) and copper formate tetrahydrate (Cu(HCOO)2•4H2O), for formic acid; copper acetate dihydrate (Cu(CH3COO)2•2H2O) and copper hydroxide acetate dihydrate (Cu4(OH)(CH3COO)7•2H2O), for acetic acid; and copper propionate (Cu4(OH)(CH3CH2COO)7•2H2O) for propionic acid.