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Abstract In this research, we propose an advanced system for the cleaning of wax-based coatings applied on indoor bronzes. To this aim we developed a new kind of eco-friendly gel based on PHB (poly-3-hydroxybutyrate) used as thickening agent, biodiesel (BD) and dimethyl carbonate (DMC). BD is a mixture of methyl esters obtained from palm oil, which acts as cleaning agent while DMC was added as additional solvent to partially solubilize PHB and forming a gelly phase. For the first time a PHB-based gel obtained by mixing two solvents with different proprieties was proposed, expanding the range of possible formulations, that can be used according to the specific restoration purpose. After the preliminary characterization of chemical and physical properties of the gel, an ad hoc analytical protocol was implemented to evaluate both the cleaning efficiency and the release of residues on the treated surfaces. Standard samples were prepared following ancient recipes and submitted to spectroscopic and chromatographic analysis before and after the cleaning procedures. Finally, the performances of PHB-DMC/BD gel were assessed on a real case of study presenting a wax-based coating: the Pulpito della passione attributed to Donatello and dated back to 1460. In situ analysis demonstrated the high cleaning efficiency of the proposed systems also for the removal of aged coatings.

To understand the composition and dynamic changes of metabolites during the formation of goose fatty liver, the metabolite profiles of goose liver at three overfeeding stages were analyzed using widely targeted metabolomics. Three 70-day-old Landes geese with similar body conditions from the same batch were selected randomly for slaughter at the early (day 7), middle (day 16) and late (day 25) overfeeding stages, separately. The tip of the larger liver lobe was collected for widely targeted metabolomic analysis. The results showed that: (1) a total of 1 153 metabolites belonging to 19 classes including amino acids, organic acids, nucleotides and lipids were detected in the liver of geese at the three overfeeding stages; (2) principal component analysis (PCA) showed significant differences in the metabolic profiles of goose liver at the three stages, and identified 142 and 92 differential metabolites at the early versus middle stage, and the middle versus late stage, respectively, the major ones being amino acids and their derivatives, as well as organic acids and their derivatives; and (3) Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis indicated that the pathways involved in fatty acid biosynthesis, vitamin B6 metabolism, linoleic acid metabolism, lysine degradation, arginine biosynthesis, arachidonic acid metabolism and amino acid biosynthesis changed significantly during the formation of goose fatty liver. This study found that most of the differential metabolites were involved in fatty acid synthesis during goose fatty liver formation. Moreover, the contents of transport-related metabolites showed a continuous increasing trend. Findings in this study will not only enrich the theoretical knowledge of poultry liver metabolism, but also provide a theoretical basis for the precise nutritional regulation and efficient production of high-quality goose fatty liver.

Interest in earthquake resilience has increased in recent years, and the use of building cluster performance objectives has been shown to be an effective method for evaluating the resilience of a built environment. A building cluster is a portfolio of buildings that share the same role in a community; its performance objectives are defined by considering earthquake scenarios, hazard levels, and individual building performance. The methodology presented in this paper employs performance-based assessments to estimate the probability of achieving building cluster performance objectives immediately following a seismic event. It can be used to assess the immediate post-earthquake community resilience in five steps: (1) hazard analysis; (2) conditional assessment of individual building performance; (3) conditional assessment of building cluster performance; (4) building cluster performance assessment by aggregation; and (5) earthquake resilience assessment of building clusters considering all hazard levels of interest. The design and extreme hazard levels are formulated using ground motion records selected based on the conditional spectra considering characteristics of earthquake scenarios and spatial correlation. Three performance objectives are defined for individual buildings and building clusters: (1) functionality; (2) safe and usable during repair; and (3) collapse prevention. Two engineering demand parameters, i.e., the maximum transient and the permanent interstory drift indices, are used to estimate individual building performance. The probability of achieving building cluster performance objective is calculated using the total probability theorem. The application of the proposed methodology is demonstrated using two clusters of reinforced concrete buildings, corresponding to ASCE 7 Risk Category II and IV structures, in San Francisco, California. [ABSTRACT FROM AUTHOR]

This study introduces a super‐fast and precise simulation algorithm capable of generating human‐visible moiré patterns, taking into account real structures with diverse patterns. The simulation of entire area of a mobile phone screen can be completed in less than 10 minutes, demonstrating a remarkable efficiency improvement of approximately 1200‐fold compared to traditional ray tracing method. The improvement comes from that we use a simplified method of calculating geometric areas instead of the first‐principles approach used in ray tracing. Based on the proposed algorithm, the moiré patterns ofAoD are optimized and the display quality is guaranteed. [ABSTRACT FROM AUTHOR]