281 research outputs found
The Monumental UNESCO Site of Panamá Viejo: Investigation of the Masonry Mortars
The presented study illustrates the characterisation of several artificial materials (bedding, joint mortars, and plasters) belonging to the masonries of the UNESCO site of Panamá Viejo, located in Panama City (Panama). This monumental site represents the first Spanish settlement on the Pacific Coast, founded 500 years ago, in 1519. Through mineralogical and petrographic analyses of the collected samples, as stereomicroscope and polarized light microscopy (PLM) observations of bulk and thin sections, respectively, environmental scanning electron microscopy and micro-chemical investigations (ESEM-EDX) and X-Ray Powder diffraction (XRPD) analysis, it was possible to identify the composition of the materials utilized for the production of mortars and plasters, in addition to the determination of their state of conservation. Therefore, this work represents a substantial step for the preservation of the Panamá Viejo site, in order to support the selection of the most suitable restoration products, such as consolidants, protectives, etc., but also for choosing the most compatible materials for possible replacements/integrations in the masonries
Climate change-induced disasters and cultural heritage: Optimizing management strategies in Central Europe
Due to climate change, it is foreseen that the frequency and magnitude of extreme climate events such as heavy precipitation, flooding and drought will increase throughout Europe. In recent times, numerous areas suffered from disasters that produced significant damage to cultural heritage. Although different risk management strategies are currently enforced in Central Europe, there still exist many challenges that undermine their effectiveness. This study reviews the necessary points to be addressed for strengthening existing management strategies within the region and the characteristics of potential resilience building measures. It presents feasible and tailored ICT solutions (e.g. a web GIS platform) and decision support tools (e.g. a manual for cultural heritage resilience and a handbook on transnational rescue procedures) for the protection of cultural heritage against floods, heavy rain and fire. These tools result from the Interreg Central Europe project ProteCHt2save, concentrating on risk assessment and sustainable protection of cultural heritage in changing environments. The proposed measures are tested at pilot sites and successfully integrated in local risk management plans. Future work is also proposed for further implementation of the results
San Fernando Batteries in Portobelo - Panama: building materials characterization and the environmental impact evaluation
[EN] The UNESCO site of San Fernando arises in the northern part of the Bay of Portobelo, on the
Panamanian Caribbean coast, and belongs to a group of military fortifications erected during the XVIIXVIII
centuries by the Spanish Empire. These defence structures were aimed at protecting the strategic
outpost for the transoceanic trade, between the "New" and the "Old World", from the pirate attacks.
In order to safeguard this impressive site, the Institute of Atmospheric Sciences and Climate, ISACCNR
(Bologna), the "Patronato de Portobelo y San Lorenzo" and the Department of Physics and Earth
Sciences of the University of Ferrara have started a collaboration for characterizing and evaluating the
state of conservation of the construction materials, considering the environmental impact on them.
Specifically this paper shows preliminary results obtained by mineralogical and petrographic
characterization carried out by Polarized Light Microscopy (PLM), Environmental Scanning Electron
Microscopy (ESEM-EDX) and X-Ray Diffraction (XRD) investigations.Ciantelli, C.; Bonazza, A.; Sabbioni, C.; Suñé MartÃnez, RA.; Vaccaro, C. (2015). San Fernando Batteries in Portobelo - Panama: building materials characterization and the environmental impact evaluation. En Defensive architecture of the mediterranean: XV to XVIII centuries. Vol. II. Editorial Universitat Politècnica de València. 353-356. https://doi.org/10.4995/FORTMED2015.2015.1754OCS35335
Characterization of hydraulic mortars from archaeological complexes in Petra
In the sixth century B.C. Petra was conquered by the Nabataeans, who built an elaborated water system and turned a desert city into an artificial oasis and a prosperous centre controlling the main commercial routes of the region (100 B.C. - 100 A.D.). In 2007, it was added to UNESCO's prestigious list of World Heritage Sites, as one of the seven wonders of the world. The aim of this research is to characterize samples of mortars lining cisterns, reservoirs and pipelines collected from the archeological site of Petra, focusing in general on the identification of the possible raw materials employed and in particular on those components conferring hydraulicity. Specifically the specimens were sampled from different structures of the Great Temple (cistern and pipelines) and of the Garden and Pool Complex (cisterns and reservoir floor). A mineralogical and petrographic characterization was carried out by polarized light microscopy (PLM) observations to identify the texture and to highlight the hydraulic reaction areas, which underwent subsequently to a more detailed morphological and elemental analysis by Scanning Electron Microscopy (SEM-EDX). X-Ray Powder Diffraction analyses (XRPD) were also performed to complete the petrographic characterization, while Thermal Analyses (DTA-TGA) were carried out to classify the level of hydraulicity of each sample. The data obtained allowed us to achieve for the first time a mineralogical and petrographic characterization of the lining hydraulic mortars present in the two archaeological complexes under study and to provide preliminary hypotheses on the provenance of the raw materials employed for their production
Risk mapping for the sustainable protection of cultural heritage in extreme changing environments
Risk mapping for the sustainable protection of cultural heritage in extreme changing environments
Cultural heritage is widely recognized to be at risk due to the impact of climate change and associated hazards, such as events of heavy rain, flooding, and drought. User-driven solutions are urgently required for sustainable management and protection of monumental complexes and related collections exposed to changes of extreme climate. With this purpose, maps of risk-prone areas in Europe and in the Mediterranean Basin have been produced by an accurate selection and analysis of climate variables (daily minimum and maximum temperature-Tn and Tx, daily cumulated precipitation-RR) and climate-extreme indices (R20mm, R95pTOT, Rx5 day, CCD, Tx90p) defined by Expert Team on Climate Change Detection Indices (ETCCDI). Maps are available to users via an interactive Web GIS (Geographic Information System) tool, which provides evaluations based on historical observations (high-resolution gridded data set of daily climate over Europe-E-OBS, 25 km) and climate projections (regional climate models-RCM, ~12 km) for the near and far future, under Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. The tool aims to support public authorities and private organizations in the decision making process to safeguard at-risk cultural heritage. In this paper, maps of risk-prone areas of heavy rain in Central Europe (by using R20mm index) are presented and discussed as example of the outputs achievable by using the Web GIS tool. The results show that major future variations are always foreseen for the 30-year period 2071-2100 under the pessimistic scenario (RCP 8.5). In general, the coastal area of the Adriatic Sea, the Northern Italy, and the Alps are foreseen to experience the highest variations in Central Europe
An integrated approach for assessing the vulnerability of World Heritage Sites to climate change impacts
One of the most difficult problem facing those responsible for managing World Heritage Sites (WHS) is climate change, as it poses continuous new challenges to the conservation of cultural heritage. Moreover, as our climate continues to change our cultural heritage will potentially be exposed to diverse pressures and potentially to risks not previously experienced. Thus, management practices will need to be tailored in order to include climate change impacts. For climate change impacts to be incorporated into preservation frameworks and management practices from government policy level down to the practice in the field, data, information and assessment methods need to be available at a scale relevant to decision-makers. This paper presents an integrated vulnerability assessment methodology and applies it to three UNESCO cultural WHS in Europe. Through this process, semi-structured interviews were conducted with academics and experts in the management and conservation of cultural heritage, as well as with the managers and coordinators of WHS. The incorporation of bottom-up knowledge in the assessment process allowed for an understanding of the sensitivity and adaptive capacity of the sites, two components of vulnerability that are not given sufficient attention and ignored, respectively, in typical top-down climate change impact assessments. In particular, the interviews elucidated the determinants that enable or constrain the capacity to adapt, i.e., resources, including technical, economic and human; information and awareness; management capacity; learning capacity; leadership; communication and collaboration; and governance; with the lack of resources most commonly mentioned as the determinant impeding adaptation. ‘Information and awareness’ and ‘management capacity’ are determinants that were not previously identified in the field of cultural heritage. The former stresses the need to disseminate the results of scientific research for their incorporation in the management of heritage sites. Vulnerability assessments such as those performed in this paper can be used to target interventions to protect and strengthen the resilience of cultural heritage to climate change impacts
On the reproducibility and repeatability of laser absorption spectroscopy measurements for δ2H and δ18O isotopic analysis
The aim of this study was to analyse the reproducibility of off-axis integrated cavity output spectroscopy (OA-ICOS)-derived δ2H and δ18O measurements on a set of 35 water samples by comparing the performance of four laser spectroscopes with the performance of a conventional mass spectrometer under typical laboratory conditions. All samples were analysed using three different schemes of standard/sample combinations and related data processing to assess the improvement of results compared with mass spectrometry. The repeatability of the four OA-ICOS instruments was further investigated by multiple analyses of a sample subset to evaluate the stability of δ2H and δ18O measurements.
Results demonstrated an overall agreement between OA-ICOS-based and mass spectrometry-based measurements for the entire dataset. However, a certain degree of variability existed in precision and accuracy between the four instruments. There was no evident bias or systematic deviations from the mass spectrometer values, but random errors, which were apparently not related to external factors, significantly affected the final results. Our investigation revealed that analytical precision ranged ±from ±0.56‰ to ±1.80‰ for δ2H and from ±0.10‰ to ±0.27‰ for δ18O measurements, with a marked variability among the four instruments. The overall capability of laser instruments to reproduce stable results with repeated measurements of the same sample was acceptable, and there were general differences within the range of the analytical precision for each spectroscope. Hence, averaging the measurements of three identical samples led to a higher degree of accuracy and eliminated the potential for random deviations
Prognostic Implications of the Complement Protein C1q in Gliomas
The contribution of the complement system in the pathophysiology of brain cancers has been recently considered in light of its well-known involvement in carcinogenesis. Complement system represents an important component of the inflammatory response, which acts as a functional bridge between the innate and adaptive immune response. C1q, the first recognition subcomponent of the complement classical pathway, has recently been shown to be involved in a range of pathophysiological functions that are not dependent on complement activation. C1q is expressed in the microenvironment of various types of human tumors, including melanoma, prostate, mesothelioma, and ovarian cancers, where it can exert a protective or a harmful effect on cancer progression. Despite local synthesis of C1q in the central nervous system, the involvement of C1q in glioma pathogenesis has been poorly investigated. We, therefore, performed a bioinformatics analysis, using Oncomine dataset and UALCAN database in order to assess whether the expression of the genes encoding for the three chains of C1q (C1qA, C1qB, and C1qC) could serve as a potential prognostic marker for gliomas. The obtained results were then validated using an independent glioma cohort from the Chinese Glioma Genome Atlas datasets. Our bioinformatics analysis, coupled with immunohistochemistry and fluorescence microscopy, appears to suggest a positive correlation between higher levels of C1q expression and unfavorable prognosis in a diverse grade of gliomas
THE CLINICOPATHOLOGICAL AND PROGNOSTIC SIGNIFICANCES OF C1Q EXPRESSION IN GLIOMAS: A BIOINFORMATICS ANALYSIS
Introduction. The complement system represents an important component of the inflammatory response and acts as a functional bridge between the innate and adaptive immune response. The contribution of the complement component C1q in the pathophysiology of brain cancers has been recently considered in light of its well-known involvement in carcinogenesis. Brain malignancies arise from cells of the CNS and are classified according to the tissue of phylogenetic origin. Gliomas
represent the most common and aggressive form of brain tumours in adults. They derive from glial cells that help to support the functions of the other main brain cells type, the neurons (1). These are a heterogeneous group of diseases with multiple subtypes (1, 2). Glioblastoma multiforme (GBM) is the most common and fatal form of a primary brain tumour, accounting for approximately 60% of all glioma cases (3), whereas grade-II and -III gliomas are the second most common type of glioma in adults (~30%) (3). C1q molecule, together with other complement components, can be locally produced within the CNS by microglia and astrocytes, rendering it an attractive player in primary brain tumour development (4). The role of C1q in gliomas microenvironment is still poorly characterized and it is still quite puzzling whether it exerts a beneficial or a harmful activity for cancer progression. In the present study we performed a bioinformatics analysis aimed at investigating if C1q can serve as a potential prognostic marker for gliomas. Methods. The expression levels of C1qA, C1qB and C1qC genes in gliomas were analysed using Oncomine analysis. Available genomics data from The Cancer Genome Atlas project was used for Kaplan–Meier survival analysis to generate survival probability plots, using UALCAN analysis. Results. From the analysis performed on several data- sets using Oncomine, we showed a significantly higher mRNA expression levels for C1qA, C1qB and C1qC chains were detected in gliomas (different histotypes and grades) as compared to normal brain tissue (Fig. 1). We observed a positive correlation between the mRNA expression of C1qA, C1qB and C1qC mRNA poly- peptide chains and the unfavorable prognosis only in gliomas grade-II and -III, where the survival probability is indeed reduced (P <0.05) (Fig. 2). No correlation was observed in glioblastoma multiforme (Fig. 2). By immu- nohistochemical approaches we detected a high depo- sition of C1q in the tumor microenvironment of both in grade-II and -III gliomas and in GBMs examined (Fig. 3a glioma, 3b glioblastoma multiforme; 20x Magnification). Moreover, in double immunocytochemical experiments we demonstrated that CD68 positive infiltrating cells are actively synthesizing C1q in the tumor micro-envi- ronment. CD68 expression is characteristic of tumor- associated macrophages, whose enrichment in glioma has been associated with poor prognosis (5). Conclusion. In our study C1q expression was significantly correlated with poor survival probability in gliomas grade-II and -III while this is not the case for GBM. These data altogether underline how complex, multifaceted and still poorly understood is the role C1q can exert on tumor progression, and how the very same molecule can differentially affect the outcome depending on the biological context it comes to act
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