Understanding residues of oil production: chemical analyses of floors in traditional mills

Oil production is an important aspect of ancient Mediterranean economy; therefore, archaeological studies on oil-producing installations using archaeometry and in particular the chemical analysis of absorbed residues is valuable in identifying the substances actually produced and to understand the spatial distribution of the activities carried out at oil mills.Modern contexts may provide a good reference for interpreting the archaeological chemical traces.This study examines the chemical traces in three abandoned oil mills in the Mediterranean: Polveraia (Tuscany, Italy), Martina Franca (Puglia, Italy) and Binibassi (Mallorca, Balearic Islands). To identify the residues released by the production of oil and absorbed by the floors, samples were taken from the floors of these installations and analysed using spot tests aimed at identifying the presence of fatty acids and phosphates. Some of the samples were analysed also with gas chromatography–mass spectrometry. The results of the analyses were plotted in the Geographic Information System (GIS) platform and interpolated with Inverse Distance Weighting (IDW) to determine the spatial distribution of the residues. Overall, the results show a large presence of fats in the analysed floors in all of the installations.     

Oxalate Patinas on Stone Monuments in the Venetian Lagoon: Characterization and Origin

Calcium oxalate patinas have been sampled on architectural elements of two ancient churches located on Torcello Island (Venetian Lagoon) and subsequently analyzed. The site had been selected presenting patinas of exceptional amount and thickness, elsewhere generally found as thin alteration layers covering stone surfaces or within black crusts on monuments in urban environments. Optical and mineralogical analyses suggest that these patinas are not the result of a simple deposition process, but originate as surface “transformations” of the substrate, and are mainly composed of dihydrate calcium oxalate (weddellite) and gypsum. Among the experimental techniques, isotope analyses (C and S) have been specifically carried out aiming at achieving a better understanding of their origin and possible causes of formation. The observed carbon isotopic fingerprint reveals in fact a strong biological fractionation recorded in the oxalate patina (δ¹³C ranging from ?22.3‰ to ?28.0‰), almost exclusively attributable to C3 pathway photosynthesis processes. Slightly negative sulfur isotope ratio values seem to be inversely correlated with patina exposure to atmospheric agents and pollutants. The results obtained prove that calcium oxalate originates from a biomineralization process induced by lichen colonization in specific environmental conditions.     

The Unstable Coastline: Navigating Dispossession and Belonging in Colombo

This article explores how residents of a small coastal fishing enclave in Colombo live with cumulative waves of dispossession brought on by exclusionary projects of urban development. Drawing on ethnographic fieldwork, I introduce the analytic of navigation to describe how people move, plan and live with both present and future threats of dispossession. Navigation offers a unique perspective on questions of agency and resistance in oppressive conditions. Rather than framing subjects as “resisting” projects of world-class city-making, this analysis shows that urban residents instead engage in complex and occasionally contradictory modes of living with uncertainty. I complicate existing understandings of the term “navigation” by describing how questions of nation and belonging are crucial to comprehending how people navigate. Ultimately, I suggest that expressions of belonging and obligation to an imagined community might not only be strategic, but instead reflect some of the broader social forces which structure possibilities for action.     

Thermographic Survey at Hagia Sophia: Main Arches,Pendentives and Tympana

Hagia Sophia is one of the oldest and most complex existing monuments. Many unanswered questions are still open on the historical and constructive evolution of this monument. The boundaries between the different construction phases and the details of the masonry and materials used in the various phases are still not defined with precision.

The thermographic survey, carried out inside the monument, made ??it possible to answer some of these questions by specifying the exact location of the past interventions and the variability of the materials employed allowing a better understanding of the constructive history of the monument. The technique was applied at a great distance and in normal environmental conditions, taking advantage of the high thermal sensitivity of the instrumentation. The results achieved confirm the validity of the technique in the study of ancient buildings.     

Comparison of Original and Modern Mortars at the Herculaneum Archaeological Site

ABSTRACT

This paper aims to evaluate mineralogical, elemental, and thermal differences among original Roman joint mortars and those used in twentieth-century restoration campaigns taken from different areas at the Herculaneum archaeological site. The purpose is to improve the compatibility of restoration mortars. Roman and modern mortars were studied with petrography, thermal analysis and x-ray fluorescence investigations. The results indicate significant differences between the Roman and modern mortars which could facilitate the degradation process. Roman mortars, in particular, were composed of a coarser aggregate which was present in a lower ratio with binder in comparison with modern mortars.     

A post-imperial,pluralist nationalism? From the Five Nation Republic of China to multicultural Taiwan

Although many nations emerged during the collapse of the empire, the case of China is curious in its failure to divide into separate nation-states. Resisting disunion, the Republic of China (ROC) adopted a rhetoric of national pluralism and laid claim to the fallen Qing Empire's vast territory. This divergence from other post-imperial nationalisms engenders questions about the legacy of imperialism in the ROC's approaches to nation-building. Such questions remain salient after the ROC retreat to Taiwan (1949), as since the end of martial law (1987), the ROC has championed itself as a model of multiculturalism. This paper examines the extent to which today's ‘Multicultural Taiwan’ paradigm differs from 20th-century official conceptualisations of pluralism, through discourse analysis of publications from the Mongolian and Tibetan Affairs Commission (MTAC). Investigation finds that despite centring Taiwan in national ideology, certain Chinese imperialist attitudes towards cultural hierarchy remained influential in MTAC representations of pluralism within Asia.     

Performance-based Seismic Risk Assessment of Urban Systems

ABSTRACT

Disaster risk mitigation has become a urgent global need. Similar to other natural hazards, earthquakes may cause significant damage on a large scale. In Europe and in other regions with dense urbanization, seismic events can heavily impact historical city centers due to the several structural fragilities. These centers are often part of the worldwide cultural heritage and their preservation is considered a strategic issue. Furthermore, earthquakes may have severe negative short-term economic effects on the impacted communities and adverse longer-term consequences for economic growth. For this reason, the development of an efficient approach for urban seismic risk assessment becomes essential. An original approach is proposed, based on performance concepts and multidisciplinary perspectives. The procedure is applied for validation to the city center of Concordia Sulla Secchia (Italy), damaged by the 2012 Pianura Padana Earthquake (PPE), comparing predicted damage scenarios with the actual post-seismic survey data.     

Seismic vulnerability assessment of historical centers at urban scale

Seismic prevention and mitigation of historical centers have gained a central position within earthquake engineering topics, particularly in areas such as Italy, Greece, and Portugal. Many historical towns in these countries have been strongly damaged, due to the high quantity of old buildings and urban structures and infrastructures. In this article, these aspects are described, modeled, and investigated in terms of structural safety, the goal being the set-up of a comprehensive strategy for seismic prevention and mitigation of a whole historical center. The proposed approach is based on two relevant parts: the first is an urban risk assessment, the second is a prioritization of retrofitting interventions so as to optimally increase urban safety.

The effectiveness of the proposed methodology is shown with reference to a complex case study, the historical center of “Montebello di Bertona”. It is initially modeled as a series/parallel system and then studied by applying seismic reliability methods. Seismic retrofitting interventions are finally prioritized.     

Combining residue analysis of floors and ceramics for the study of activity areas at the Garum Shop at Pompeii

In this paper, we propose the application—for the first time in the Mediterranean area—of the combination of the study of chemical residues in floors and ceramics, with the aim of providing information about the activities carried out in archeological buildings. We chose the Garum Shop at Pompeii to test the method. In fact, due to the peculiarity of this archeological context, it provided an ideal case in which the activities performed are in part known, and the ceramic vessels recovered are still in situ. Floor samples were studied by means of spot tests developed in Mexico aimed at identifying the presence of phosphates, fatty acids, and protein residues, while the organic residues preserved in the ceramic matrix of amphorae, dolia, and other ceramic vessels were studied by gas chromatography coupled with mass spectrometry. Moreover, we integrated the data obtained with specific studies directed at better identifying the solid residues found inside two of the amphorae studied: botanical studies of fruit stones recovered in a Dressel 20 amphora and the characterization of the lime preserved in an African amphora. The research allowed for the identification of the traces of some of the activities performed, such as cooking and producing garum in the floors of the building, and the use and re-use of amphorae and dolia before the Vesuvian eruption.