21 research outputs found

    Pyroclastic Stones as Building Materials in Medieval Romanesque Architecture of Sardinia (Italy): Chemical-Physical Features of Rocks and Associated Alterations

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    The paper discusses the chemical-physical-petrographic features and decay processes of San Nicola Church (11th−14th century) building materials, one of the most representative Medieval Churches in Sardinia, stylistically attributable to the Romanesque architecture. The monument was built up into two stages and shows a characteristic size uniformity of the ashlars. The masonry is mainly made up of rhyodacitic pyroclastites belonging to the Sardinian Eocene-Miocene mag- matic phase (38–15 My). These volcanic rocks were widely used in Medieval architecture for the excellent workability, but its minero-petrographic features greatly favor the decay, due to the action of chemical-physical alteration processes. Although the alteration degree and macroscopic forms of decay vary from zone to zone in the monument, according to the different compositional features of the volcanic stones, weathering and exposure condition, the pyroclastic rocks are generally affected by greater alteration than other igneous lithotypes, due to their petrographic- volcanological characteristics (e.g., low-medium welding grade, medium-high porosity). The results concerning mineralogical and petrographic features, respectively, carried out by the application of X-Ray Powder Diffraction (XRPD), Optical Microscope (OM), and Scanning Electron Microscope (SEM) techniques, both on fresh building rocks and associated alterations, are here presented and discussed. Furthermore, the relationships between fresh pyroclastites and altera- tion processes affecting these rocks will be discussed

    Geomaterials and decay forms of the coastal towers of Piscinni and Foghe, Weastern Sardinia

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    [EN] The distribution of Coastal Towers in Sardinia testify that foreign invasions, which occurred several times over the centuries, were particularly frequent and dangerous. The beginning of the eighth century signed an increase of the attacks from the sea. The most of Coastal Towers were built in the period of Spanish rule, from 1583 to 1720. Despite numerous restorations over the years, many of these defensive structures are in critical conditions, some also affected by structural collapse. The building materials are closely related to local geological outcrops, and consist of sedimentary, magmatic and metamorphic rocks. Study of different lithotypes allowed assessing the vulnerability of different materials in different environmental conditions. Salts, transported by aerosols and deposited inside the porous structures, are the principal cause of decay of the building materials. Chemical-physical and mineralogical-petrographic analyses, performed on some Towers allowed making some general assessments on their conservation status and restoration projects.Carcangiu, G.; Meloni, P.; Palomba, M.; Cocco, O.; Sitzia, F.; Murru, A.; Carboni, M.... (2015). Geomaterials and decay forms of the coastal towers of Piscinni and Foghe, Weastern Sardinia. En Defensive architecture of the mediterranean: XV to XVIII centuries. Vol. I. Editorial Universitat Politècnica de València. 345-352. https://doi.org/10.4995/FORTMED2015.2015.1753OCS34535

    Adaptation of multiple-use forest management to climate change in a southern Alpine district. Pilot activity in Boite Valley

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    The C3-Alps project seeks to synthesize, transfer, and implement the best available knowledge on adaptation in both policy and practice, building on the results from previous projects and initiatives on adaptation to climate change in the Alps. By applying a knowledge-transfer concept driven by the information and communication needs of project target groups, the project optimizes the usability of available knowledge resources in an attempt to bridge the gap between the generation of adaptation knowledge and its application in the real-world decision-making. The project involves stakeholders in different ways, with participatory events and through eParticipation in the form of online surveying and collaboration on problem-analysis and solution-finding, in order to support bottom-up adaptation measures in the Alpine regions and municipalities. The forest district level of planning proposes a strategy for the operational local forest plans. Therefore, at this level, the long-term objective of implementing multiple-use forest management which copes with climate and land-use change is better ensured. For this reason, we tested how an understanding of change consequences on local forest types may enable a focus on delivering adaptation measures in the forest district plan of a south-eastern alpine region

    Decay Detection in an Ancient Column with Combined Close-Range Photogrammetry (CRP) and Ultrasonic Tomography

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    This study presents the integrated application of a few non-destructive techniques, i.e., Close Range Photogrammetry (CRP), and low frequency (24 kHz) ultrasonic tomography comple-mented by petrographical analysis. The aim here is to assess the conservation state of a Carrara marble column in the Basilica of San Saturnino, which is part of a V-VI century Palaeo Christian complex in the city of Cagliari (Italy). The high resolution 3D modelling of the studied artifact was computed starting from the integration of proximal sensing techniques, such as CRP based on the Structure from Motion (SfM) technique, which provided information on the geometrical anomalies and reflectivity of the investigated marble column surface. The inner parts of the studied body were inspected successfully in a non-invasive way by computing the velocity pattern of the ultrasonic signal through the investigated materials, using 3D ultrasonic tomography. The latter was optimally designed based on the 3D CRP analysis and the locations of the source and receiver points were detected as accurately as possible. The integrated application of in situ CRP and ultrasonic techniques provided a full 3D high resolution model of the investigated artifact, which made it possible to evaluate the material characteristics and its degradation state, affecting mainly the shallower parts of the column. The 3D visualisation improves the efficiency, accuracy, and completeness of the interpretative process of data of a different nature in quite easily understood displays, as well as the communication between different technicians. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    Prevalence of malocclusion in children with obstructive sleep apnoea

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    OBJECTIVES: To describe the prevalence of malocclusions in 2- to 10-year-old children suffering from obstructive sleep apnoea (OSA) and to evaluate the association between occlusal variables and OSA. SETTING AND SAMPLE POPULATION: A total of 2101 consecutive patients referred to an otorhinolaryngology unit were considered for the study. One hundred and fifty-six children (range 2-10 years) with suspected OSA were selected for a sleep study. The final sample consisted of 139 children suffering from OSA and a control group of 137 children. MATERIALS AND METHODS: All patients included in the study underwent a clinical orthodontic examination to record the following occlusal variables: primary canine relationship, presence of a posterior crossbite, overjet and overbite. Odds ratios and 95% confidence intervals, comparing the demographic characteristics and dental parameters in OSA vs non-OSA children, were computed. Multivariable logistic regression models were developed to compare independent variables associated with OSA to non-OSA children. RESULTS: The prevalence of malocclusions in children with OSA was 89.9% compared to 60.6% in the control group (P < 0.001). Factors independently associated with OSA compared to the control group were posterior crossbite (OR = 3.38; 95%CI:1.73-6.58), reduced overbite (OR = 2.43; 95%CI:1.15-5.15.), increased overbite (OR = 2.19; 95%CI:1.12-4.28) and increased overjet (OR = 4.25; 95%CI:1.90-9.48). CONCLUSIONS: This study showed a high prevalence of malocclusion in children with OSA compared to the control group. The posterior crossbite and deviations in overjet and overbite were significantly associated with OSA. The presence of these occlusal features shows the importance of an orthodontic evaluation in screening for paediatric OS

    Pianificazione forestale di indirizzo territoriale - Comunit\ue0 Montana della Valle del Boite

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    This forest plan seeks to synthesize, transfer, and implement the best available knowledge on adaptation in both policy and practice, building on the results from previous projects and initiatives on adaptation to climate change in the Alps. By applying a knowledge-transfer concept driven by the information and communication needs of project target groups, the plan optimizes the usability of available knowledge resources in an attempt to bridge the gap between the generation of adaptation knowledge and its application in the real-world decision-making. The plan involves stakeholders in different ways, with participatory events and through eParticipation in the form of online surveying and collaboration on problem-analysis and solution-finding, in order to support bottom-up adaptation measures in the Alpine regions and municipalities. The forest district level of planning proposes a strategy for the operational local forest plans. Therefore, at this level, the long-term objective of implementing multiple-use forest management which copes with climate and land-use change is better ensured. For this reason, we tested how an understanding of change consequences on local forest types may enable a focus on delivering adaptation measures in the forest district plan of a south-eastern alpine region

    Development and Chemico-Physical Characterization of Ovine Milk-Based Ingredients for Infant Formulae

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    The great majority of infant formula (FM) for neonate&rsquo;s nutrition are produced using ingredients from cow milk. Recently, some countries, such as China and New Zealand, are turning their attention to the use of ovine milk ingredients for FM production. In this study, a pilot plant process has been set up to produce infant formula ingredients from Sarda sheep milk. To meet the nutritional needs of neonates (0&ndash;6 and 6&ndash;12 months of age) two different liquid milk-derived formulations (IF1 and IF2, respectively) obtained mixing whole milk, skimmed milk, and whey milk ultrafiltration concentrate (retentate) were produced. Compositional analysis of milk, retentate, and the final IFs showed that the two formulations contain elements of nutritional interest, such as well-balanced content of high biological value proteins (casein:whey proteins ratio of 30:70 and 60:40 for IF1 and IF2, respectively), vitamin A, E and B5, cholesterol, minerals, nucleotides, free amino acids and essential fatty acids (n&ndash;6:n&ndash;3 ~1), compatible with the growth and development needs of neonates. Therefore, the obtained IF1 and IF2 can be proposed as valuable ovine dairy ingredients for FM manufacturing. Further studies will be necessary to verify the adaptability of the developed process from laboratory to industrial scale application
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