NonDestructive Techniques for the Assessment and Preservation of Historic Structures

The preservation of the built heritage has long been a public concern, mainly due to fears about the loss of identity, history and heritage of populations. The main concerns are the conservation and restoration of monuments that usually represent important events in the history of a city or a country. More recently, urban residents and policymakers have become aware of the abandonment or degradation of old city cores, leading to mischaracterisation of the buildings and ways of living. To preserve history and promote building and urban renewal, considering the basic principles of the preservation process, it is important to introduce the least possible disturbance. To start with, the diagnostic process is a key aspect, especially to investigate the construction characteristics and the damage to materials, and to find structural and nonstructural problems. To start any process, a visual inspection, a study and knowledge of the original construction methods and materials and historical repair techniques can help but may not be sufficient, and the use of conventional techniques to complement the information needed can result in an insufficient understanding or in extensive and unnecessary intrusions in the construction. In recent years, the rapid growth of science and research, combined with the industry and the need to gather more and accurate information, have led to the fast development of nondestructive testing methodologies that allow the architectural archaeology to be studied, the structural assessment to be supported and information to be given about the material properties. Each technique can be used for a specific purpose, but, in some cases, only a combination of techniques is reliable and gives an accurate interpretation of the data acquired. The fundamental contribution and aim of this book is to give a full overview of several case studies where different nondestructive techniques have been applied, in several cases using multidisciplinary approaches, which aim to highlight the importance of the information acquired and encourage the use of these techniques in future studies. The book brings together 16 chapters focused on nondestructive testing techniques applied at the urban building level and also applied to monumental buildings, archaeology and cultural heritage, bringing together more than 40 international researchers and experts in the field, who are the source of practical case studies supported by a theoretical background.info:eu-repo/semantics/publishedVersio

Mini-review and discussion of a potential standardization

Gonçalves, G., Andriolo, U., Gonçalves, L. M. S., Sobral, P., & Bessa, F. (2022). Beach litter survey by drones: Mini-review and discussion of a potential standardization. Environmental Pollution, 315(15 December), 1-8. [120370]. https://doi.org/10.1016/j.envpol.2022.120370The abundance of beach litter has been increasing globally during the last decades, and it is an issue of global concern. A new survey strategy, based on uncrewed aerial vehicles (UAV, aka drones), has been recently adopted to improve the monitoring of beach macro-litter items abundance and distribution. This work identified and analysed the 15 studies that used drone for beach litter surveys on an operational basis. The analysis of technical parameters for drone flight deployment revealed that flight altitude varied between 5 and 40 m. The analysis of final assessments showed that, through manual and/or automated items detection on images, most of studies provided litter bulk characteristics (type, material and size), along with litter distribution maps. The potential standardization of drone-based litter survey would allow a comparison among surveys, however it seems difficult to propose a standard set of flight parameters, given the wide variety of coastal environments, the different devices available, and the diverse objectives of drone-based litter surveys. On the other hand, in our view, a set of common outcomes can be proposed, based on the grid mapping process, which can be easily generated following the procedure indicated in the paper. This work sets the ground for the development of a standardized protocol for drone litter data collection, analysis and assessments. This would allow the provision of broad scale comparative studies to support coastal management at both national and international scales.publishersversionpublishe

A method to incorporate uncertainty in the classification of remote sensing images

The aim of this paper is to investigate if the incorporation of the uncertainty associated with the classification of surface elements into the classification of landscape units (LUs) increases the results accuracy. To this end, a hybrid classification method is developed, including uncertainty information in the classification of very high spatial resolution multi-spectral satellite images, to obtain a map of LUs. The developed classification methodology includes the following steps: (1) a pixel-based hard classification with a probabilistic Bayesian classifier; (2) computation of the posterior probabilities and quantification of the classification uncertainty using an uncertainty measure; (3) image segmentation and (4) object classification based on decision rules. The classification of the resulting objects into LUs is performed considering a set of decision rules that incorporate the pixelbased classification uncertainty. The proposed methodology was tested on the classification of an IKONOS satellite image. The accuracy of the classification was computed using an error matrix. The comparison between the results obtained with the proposed approach and those obtained without considering the classification uncertainty revealed a 12% increase in the overall accuracy. This shows that the information about uncertainty can be valuable when making decisions and can actually increase the accuracy of the classification results.info:eu-repo/semantics/publishedVersio

Assessment of the state of conservation of buildings through roof mapping using very high spatial resolution images

The assessment of the state of conservation of buildings is extremely important in urban rehabilitation. In the case of historical towns or city centres, the pathological characterization using traditional methods is a laborious and time consuming procedure. This study aims to show that Very High Spatial Resolution (VHSR) multispectral images can be used to obtain information regarding the state of conservation of roofs where, usually, building degradation starts. The study was performed with multispectral aerial images with a spatial resolution of 0.5 m. To extract the required information, a hybrid classification method was developed, that integrates pixel and object based classification methods, as well as information regarding the classification uncertainty. The proposed method was tested on the classification of the historical city centre of Coimbra, in Portugal, that includes over than 800 buildings. The results were then validated with the data obtained from a study conducted during 2 years by a nine element team from the University of Coimbra, using traditional methods. The study performed achieved a global classification accuracy of 78%, which proves that the state of conservation of roofs can be obtained from VHSR multispectralimages using the described methodology with a fairly good accuracy.info:eu-repo/semantics/publishedVersio

Subsurface dynamic evaluation to identify old quarries in urban areas : Lisbon city case study

The urban expansion over the last century in Lisbon has created a lot of pressure in the suburbs leading to construction taking place in less favourable terrains. These areas were also occupied by an extensive mining industry, for the extraction of massive limestones for building and ornamental stone that had an important role for the reconstruction of Lisbon after the earthquake of 1755. Due to its heavily urbanized landscape in the last century, the terrain morphology is often changed by non-natural processes such as excavations and landfill deposits and nowadays the exact location where these exploitations took place is unknown leading to potential risk situations for buildings, infrastructures and the local population. The aim of this study was to perform a detailed subsurface dynamic analysis to locate the quarries and their landfill material thickness. For that, cartographic and topographic information dating from 1911, 1950, 1970, 2012 were used to create digital terrain models which allowed the terrain morphology changes to be identified and the volume of landfill materials to be obtained. This study enables the Town Hall to create constraints in land use in their Master Plan and other planning instruments to reduce cost increases and the risk of hazards.info:eu-repo/semantics/publishedVersio

Acoustics of Modern and Old Museums

The goal of this study is to acoustically characterize typical modern and old museums. Modern museums can easily have a bad acoustic behavior due to the widespread use of very smooth and reflective coatings, hard floors, high-ceilings and very expressive volumes. This situation is not usually seen in "old" museums. Acoustic analyses of two case-studies (the 1999 Contemporary Art Museum of Serralves and the National Museum of Soares dos Reis, in Porto, Portugal) are held using objective parameters measured in situ in their largest showrooms (RT, RASTI, LAeq background noise HVAC and NC/NR). This work studies the generic acoustic requirements of these buildings and recommends optimal values for those parameters. Some proposals for the acoustical improvement in the main rooms are suggested. A short comparison of results with other museums is shown

A multi-criterion method to assess the acoustic quality in museums

This paper proposes a multi-criteria analysis model to acoustically characterize a specific type of building: museums. Significant acoustic objective parameters are used and logically weighted (after analysis of questionnaires and interviews for subjective responses of visitors) to find a representative unique index of evaluation of a room, the IAQM (Index of Acoustic Quality in Museums) rated on a scale from 0 (worst) to 20 (best). The acoustic parameters used are: Reverberation Time (RT), weighted standardized sound level difference of facades (D2m,nT,w), Rapid Speech Transmission Index (RASTI), LAeq (from HVAC background noise) and L'nT,w (weighted standardized field impact sound pressure level). The multi-criteria mathematical model is presented and numerically tested with two museums

Inconsistent recognition of uncertainty in studies of climate change impacts on forests

Petr, M., Vacchiano, G., Thom, D., Mairota, P., Kautz, M., Gonçalves, L. M. D. S., ... Reyer, C. P. O. (2019). Inconsistent recognition of uncertainty in studies of climate change impacts on forests. Environmental Research Letters, 14(11), 1-13. [113003]. https://doi.org/10.1088/1748-9326/ab4670Background. Uncertainty about climate change impacts on forests can hinder mitigation and adaptation actions. Scientific enquiry typically involves assessments of uncertainties, yet different uncertainty components emerge in different studies. Consequently, inconsistent understanding of uncertainty among different climate impact studies (from the impact analysis to implementing solutions) can be an additional reason for delaying action. In this review we (a) expanded existing uncertainty assessment frameworks into one harmonised framework for characterizing uncertainty, (b) used this framework to identify and classify uncertainties in climate change impacts studies on forests, and (c) summarised the uncertainty assessment methods applied in those studies. Methods. We systematically reviewed climate change impact studies published between 1994 and 2016. We separated these studies into those generating information about climate change impacts on forests using models -'modelling studies', and those that used this information to design management actions-'decision-making studies'. We classified uncertainty across three dimensions: nature, level, and location, which can be further categorised into specific uncertainty types. Results. We found that different uncertainties prevail in modelling versus decision-making studies. Epistemic uncertainty is the most common nature of uncertainty covered by both types of studies, whereas ambiguity plays a pronounced role only in decision-making studies. Modelling studies equally investigate all levels of uncertainty, whereas decision-making studies mainly address scenario uncertainty and recognised ignorance. Finally, the main location of uncertainty for both modelling and decision-making studies is within the driving forces-representing, e.g. socioeconomic or policy changes. The most frequently used methods to assess uncertainty are expert elicitation, sensitivity and scenario analysis, but a full suite of methods exists that seems currently underutilized. Discussion & Synthesis. The misalignment of uncertainty types addressed by modelling and decision-making studies may complicate adaptation actions early in the implementation pathway. Furthermore, these differences can be a potential barrier for communicating research findings to decision-makers.publishersversionpublishe

Phenolic extraction of Moringa oleifera leaves in DES: characterization of the extracts and their application in methylcellulose films for food packaging

In this work, a qualitative study of the phenolic content of Moringa oleifera leaves (MO), extracted with deep eutectic solvents (DES) based on choline chloride (ChCl) with lactic acid (LA) or glycerol (GLY), was performed by high-resolution mass spectrometry (HPLC-DAD-ESI-MSn). The two solvents (DES-LA and DES-GLY) extract similar classes of phenolics, and ten compounds were identified. The antioxidant profile was also studied (TPC, TFC, DPPH, FRAP, ORAC, and ABTS). Both solvents show an efficient extraction of phenolic compounds and high antioxidant capacity was verified for the extracts. However, the DES-Gly have a higher capacity for polyphenolic extraction (TPC led to 38.409 ± 0.095 mg GAE.g−1 and 2.259 ± 0.023 mg QE.g−1 for TFC). Films based on methylcellulose (MC) containing different amounts of DES or MO extracts, acting as plasticizers, were developed and characterized regarding their mechanical, optical, water vapor permeability, and microstructural properties. All films are uniform, clear, and transparent with smooth, homogeneous surfaces. It was found that the presence of more than 10% of MO extract and/or DES provided more flexible films (Eb for MC 2%_DES 20% achieved 4.330 ± 0.27 %, and 8.15 ± 0.39 % for MC 2%_MO 20%) with less mechanical and barrier resistance. The ultimate objective of this study was to provide information that could assist in the development of antimicrobial active methylcellulose films for sliced wheat bread packaging.Projects UIDB/50006/2020 and UIDP/50006/2020, funded by FCT/MCTES through national funds

HOXA9 promotes glioblastoma initiation, aggressiveness and resistance to therapy

Glioblastoma is the most common and malignant subtype of glioma, exhibiting remarkable resistance to treatment. Here we investigated the oncogenic potential of HOXA9 in gliomagenesis, the molecular and cellular mechanisms by which HOXA9 may render glioblastoma more aggressive, and how HOXA9 affects response to chemotherapy and prognosis. Expression microarrays were used to identify HOXA9 target genes. Stable glioblastoma cell lines with ectopic HOXA9 overexpression or shRNA-­mediated knockdown of HOXA9 were established to evaluate the roles of HOXA9 in cell viability, death, invasion, and response to temozolomide. Subcutaneous and orthotopic intracranial xenograft models of glioblastoma were established to evaluate the oncogenic potential of HOXA9 in vivo, and its role in response to temozolomide and overall survival. Transcriptomic analyses identified novel HOXA9-­target genes that have key roles in critical cancer processes, including cell proliferation, adhesion, DNA metabolism and repair, and stem cell maintenance. Functional assays with a variety of glioblastoma cells revealed that HOXA9 promotes cell viability, stemness, and invasion; conversely, HOXA9 displayed anti-­apoptotic functions. Additionally, ectopic expression of HOXA9 promoted the malignant transformation of human immortalized astrocytes in an intracranial orthotopic mouse model of glioblastoma, and caused tumor-­associated death. HOXA9 also mediated resistance to temozolomide treatment both in vitro and in vivo. Mechanistically, BCL2 was identified as a novel HOXA9 target that may be therapeutically targeted. Indeed, the pharmacological inhibition of BCL2 with ABT-­737 specifically reverted temozolomide resistance in HOXA9-­positive cells. These data establish HOXA9 as a critical driver of glioma initiation, aggressiveness and resistance to therapy