Maintenance is crucial for the durability of the existing building stock and should be perceived as an opportunity to improve the built environment. The implementation of thermal retrofitting measures to the building’s envelope enhances global energy performance, which is economically and environmentally beneficial. Building-related energy consumption during the operation phase is key to tackling carbon neutrality and climate change. Introducing thermal retrofitting within the context of maintenance planning can be cost-optimizing, as it reveals the technical–economic synergy between building pathology and energy efficiency. Maintenance activities and energy demand throughout the building’s service life influence life-cycle costs (LCCs). Decision-making based on LCC awareness is an advantage for owners. This study discusses the impact of implementing an optimal retrofitting solution (ORS), according to different maintenance strategies, on the LCC of an existing single-family home. The ORS comprises the following measures: adding an external thermal insulation composite system (ETICS) to external walls, extruded polystyrene (XPS) panels to the roof, and replacing the existing windows with others with improved thermal performance. The three maintenance strategies involve different complexity levels, concerning the type, number and timing of activities. Moving beyond isolated assessments, this study develops an integrated framework that bridges based on two existing background methodologies, involving optimal thermal retrofitting and condition-based maintenance planning, which, combined with new research, enable the assessment of maintenance, energy and global LCC for a time horizon of 100 years. The evaluation of energy-related LCC is based on simulations. The results indicate that these costs represent the majority of the global LCC. The ORS has a considerable positive impact on energy and global LCC. Adopting a maintenance strategy characterized by fewer planned activities and an earlier schedule of replacement interventions, which determines the implementation of the retrofitting measures, is better in terms of LCC savings.

A building’s energy performance, in terms of thermal comfort, energy demand, cost and CO2 emissions, is considerably affected by its envelope. Enhancing energy efficiency through maintenance and retrofitting is essential to reduce consumption and emissions, thereby mitigating climate change. However, selecting the most cost-effective retrofitting solution remains challenging for decision-makers. Analysing real data across multiple scenarios provides valuable insights, supporting informed decision-making. This study discusses the impact of thermal retrofitting decisions on the energy efficiency of an existing single-family home, by analysing multiple scenarios concerning the implementation of measures on external walls, roof and windows. Both generalized and tailored approaches, particularly for external walls, are evaluated. Options include different insulation materials for the roof and façades—with the latter employing an external thermal insulation composite system (ETICS)—and various framing materials with double-glazing for window replacement. Various scenarios are discussed based on thermal simulations, implementation costs, and cost-benefit analysis. Additionally, multi-criteria (MCA) and sensitivity (SA) analyses are conducted to determine the optimal retrofitting solution. The most effective combined strategy applies ETICS with rock wool on the external walls, extruded polystyrene panels on the roof, and aluminium-framed windows with a thermal break, balancing energy efficiency, costs, durability, and sustainability. Although not part of the optimal solution, tailored retrofitting of façade F2 presents a viable alternative under cost constraints.

As climate change continues to manifest its effects globally, the built environment faces escalating challenges in maintaining functionality and resilience against extreme weather events. This study analyses the interaction between functional service life and building resilience amidst climate change impacts, focusing on contrasting regions within Chile: the north and extreme south. Through a series of 158 case studies, this research examines how buildings in these regions adapt and endure under changing climatic conditions. Employing a qualitative and quantitative approach, data collection involved on-site inspections, interviews with stakeholders, and analysis of historical records. The findings underscore the importance of localized solutions tailored to the specific climatic challenges faced by each region. Furthermore, the research highlights the significance of proactive measures such as robust design, materials selection, and maintenance protocols in enhancing building resilience. By synthesizing insights from diverse climatic contexts, this study contributes to a broader understanding of the complex dynamics shaping the functional service life and resilience of buildings in Chile. Finally, the findings offer some guidance for different stakeholders seeking to enhance the built environment against the escalating impacts of climate change.

This study presents an exploratory statistical analysis of 1616 corrosion-induced incidents in US gas transmission pipelines, using data from the Pipeline and Hazardous Materials Safety Administration between 1970 and 2023. The analysis identifies patterns and trends in corrosion-related failures, emphasising the main factors influencing pipeline degradation, the effectiveness of mitigation strategies, and the risks inherent in current operations. Results indicate an average service life of around 38 years for corrosion-affected pipelines, with external corrosion and localised pitting as the most prevalent mechanisms. Significant regional variations are linked to pipeline density and climatic conditions. The findings highlight the importance of material selection, climate adaptation, and advanced corrosion prevention techniques in extending pipeline integrity and service life. The study underscores the need to prioritise high-risk regions and aging infrastructure for targeted maintenance and investment. By providing quantitative insights into the temporal and spatial dimensions of corrosion failures, the research supports data-driven strategies to enhance pipeline safety, reliability, and cost efficiency. This study also proposes policy guidance, encouraging for updated integrity management programs, incentives for corrosion-resistant materials, and research into innovative prevention technologies to ensure long-term resilience and public safety.

This study evaluates the influence of the type of finishing, i.e. paint or ceramic tile, on the performance of rendered facades, through hygrothermal simulation and tensile bond strength tests. The research combines computer simulations with experimental data obtained from buildings located in Brasília, allowing for the observation of how different types of finishing affect the physical and mechanical behavior of mortar exposed to climate variations. The results show that the system with ceramic tile finish presents better thermal and hygroscopic performance, with lower temperature amplitude, smaller variation in relative humidity, and lower accumulated moisture content over time. These factors are directly related to better results in the bond strength tests, validating the role of ceramic finish as an effective protective layer for the mortar. In contrast, the system with paint showed greater vulnerability to environmental fluctuations and lower bond strength performance. The results highlight the critical role of surface finishing in the durability of rendered façades. It is therefore recommended that, in technical inspections, the mortar and the surface finishing be evaluated independently, especially in multi-layer systems. This research contributes to the refinement of technical and regulatory criteria for selecting and evaluating facade rendering systems.

The durability of facade coatings is often compromised by incorrect specifications and a lack of technical knowledge, leading to reduced service lives of buildings and their components. This study analyzes how key construction characteristics affect the adhesion of mortars used in facade coatings. Tensile adhesive strength tests were conducted on in-use buildings to assess the quality of mechanical resistance and overall construction performance. The analysis highlights critical factors influencing adhesion strength, including finish type, building age, and solar orientation. Cohesive failures—particularly types E and F, as defined by Brazilian standards—were prevalent, emphasizing the importance of analyzing the types of rupture when discussing the results of adhesion tests. The results highlight that, among the various factors influencing adhesion strength, the type of finish and solar orientation play a significant role. Notably, north-facing external facades are more susceptible to adhesion failures, regardless of the type of finish. However, when considering only adhesive failures (Types B, C, or D), ground orientation tends to exhibit adhesion strength values below the normative limits. These findings provide actionable insights into improving facade performance and optimizing construction processes. By identifying the variables that significantly affect bond strength, this study offers a valuable reference for better decision-making in construction and the long-term durability of building coatings.

The possibility of diagnosing and repairing specific sets of defects (those with more severe consequences and impact on the degradation of building components) with the same means is considered. It is important to optimise the planning and kick-off of building inspections by using, from the start, a predetermined set of equipment and to optimise the maintenance and rehabilitation of the building envelope in terms of funds invested and resources. An existing methodology is used to create inter-defect correlation matrices, taking into account an expert knowledge-based building inspection system. The main results include a set of essential diagnosis methods—crack measuring and monitoring; temperature and moisture measurement; infrared thermography; and water absorption tests—and the identification of the most transversal repair techniques—cleaning; protection coating; replacement/reapplication of claddings/glazing; re-application of finishing coats or more adequate claddings—which were also analysed in terms of resource consumption, as a preliminary approach to their life-cycle assessment. The main conclusions indicate that there is still a long path to cover in the field of life-cycle assessment of repair techniques, which can be extended to the application of diagnosis methods.

Maintenance decisions often extend beyond physical deterioration, with stakeholders' experiences playing crucial roles. Traditionally, building assessments rely on visual inspections, but manual methods have limitations (e.g., time and cost expensive, relying on subjective assessment). “Feeling-BIM” proposes a new methodology whose concept integrates automated facade inspection with residents' sentiments. Incorporating residents' feelings acknowledges the prevalence of subjective criteria in maintenance decisions, with a particular focus on facade stains that influence interventions and building aesthetics. Three buildings with the same archetype and in the same street, in different degradation conditions, are analysed as case study. A sentiment analysis is performed, to evaluate the ability of residents to clearly distinguish between facades in the best condition and those identified by automated inspection as having a higher presence of stains. “Feeling-BIM” empowers decision-makers with a more comprehensive perspective on facades’ condition, ensuring that decisions are well-informed and balanced, considering both objective and subjective factors.

The effect of climate change on the durability of buildings and external components is considered a relevant subject that requires research efforts. This study intends to contribute to the body of knowledge in this field through a practical-based, innovative quantitative methodology. This methodology is created to model the degradation evolution of rendered fa & ccedil;ades and project it based on the influence of the climate change signal for individual variables, considering their gradual impact. A sample of 26 rendered fa & ccedil;ades in residential buildings in Lisbon has been subjected to recent on-site visual inspections, to evaluate each case study's degradation condition. Previous inspections had been performed more than a decade ago in the context of a background methodology. This research highlights the influence of (i) maximum temperatures (TX) on global mean triennial degradation rates (triangle S-w,S-mt), for a period of 30 years (1990-2020), and (ii) TX projections on degradation evolution from the date of the recent inspections until the last triennium of the reference degradation projections period (Delta S-wFR and Delta S-wFRN) (2020-2044). The correlation between TX and Delta S-w,S-mt is significant, which indicates that the increase in maximum temperatures considerably explains the decrease in degradation rates from 1990 to 2020. The future global degradation of rendered fa & ccedil;ades based on TX scenarios is expected to (i) be lower than the one based on a historical observed trend and (ii) be the lowest when the temperature rise is the highest. Temperature warming, even though detrimental to some degradation phenomena, is expected to decelerate the overall degradation evolution of rendered fa & ccedil;ades in Portugal and possibly in analogous areas of the Mediterranean.

Background: Immune cells from rheumatoid arthritis (RA) patients display a reduced in vitro response to Porphyromonas gingivalis (P. gingivalis), which may have functional immune consequences. The aim of this study was to characterize, by flow cytometry, the frequency/activity of monocytes and naturally occurring myeloid dendritic cells (mDCs) in peripheral blood samples from patients with periodontitis and patients with periodontitis and RA. Methods: The relative frequency of monocytes and mDCs in the whole blood, the frequency of these cells producing TNFα or IL-6 and the protein expression levels for each cytokine, before and after stimulation with lipopolysaccharide (LPS) from Escherichia coli plus interferon-γ (IFN-γ), were assessed by flow cytometry, in peripheral blood samples from 10 healthy individuals (HEALTHY), 10 patients with periodontitis (PERIO) and 17 patients with periodontitis and RA (PERIO+RA). Results: The frequency of monocytes and mDCs producing IL-6 or TNF-α and the expression of IL-6 and TNF-α in the PERIO group were generally higher. Within the PERIO+RA group, P. gingivalis and related antibodies were negatively correlated with the monocyte and mDC expression of IL-6. A subgroup of the PERIO+RA patients that displayed statistically significantly lower frequencies of monocytes producing IL-6 after activation presented statistically significantly higher peptidylarginine deiminase (PAD)2/4 activity, anti-arg-gingipain (RgpB) IgG levels, mean probing depth (PD), periodontal inflamed surface area (PISA) and bleeding on probing (BoP). Conclusions: In the patients with PERIO+RA, innate immune cells seemed to produce lower amounts of pro-inflammatory cytokines, which are correlated with worse periodontitis-related clinical and microbiological parameters.

Buildings represent a significant portion of energy consumption and greenhouse gas emissions globally, emphasizing the urgency to address energy efficiency for mitigating climate change. Despite recognized importance, existing models often demonstrate discrepancies between predicted and actual energy demands in buildings, underscoring the need for real-world data analysis over prolonged periods to identify trends, householders' behaviors, and challenges. This paper presents a comprehensive analysis of the energy consumption patterns in a single-family house over ten years, focusing on the impact of microgeneration in enhancing energy efficiency and reducing carbon emissions. Statistical analysis techniques were applied to assess energy consumption trends and the impact of renewable energy integration. Results show that the incorporation of photovoltaic solar panels and a battery notably reduce energy costs, especially post-2020, despite homeowners' prolonged stay-at-home during COVID-19 lockdowns. The findings highlight the evolving trends in energy consumption and the role of renewable energy solutions in promoting energy efficiency and resilience in residential settings, suggesting that these technologies can mitigate greenhouse gas emissions and decrease reliance on fossil fuels.

Climate change could alter the natural degradation pattern of buildings and their components. Façade claddings are directly exposed to the action of environmental agents, thus being particularly vulnerable to climate change impacts. Determining the expected degradation of the façades’ external layer, according to climate parameters’ projections, could be useful in the context of maintenance planning and adaptation to climate change. The present study intends to deepen the knowledge about the influence of temperature on the degradation evolution of rendered façades, considering the analysis of possible correlations between variables, based on observed and recorded climate data. It covers the degradation evolution of a sample of 26 rendered façades located in Lisbon, Portugal, based on the mean triennial degradation rate (∆Sw,mt) for periods of three years between 1990 and 2020. The severity of degradation index (Sw) of each façade, assessed through visual inspections in two moments in time, is used to model the individual degradation of the respective case study, necessary to calculate the sample’s ∆Sw,mt of to each triennium. The correlation between the dependent variable ∆Sw,mt and the independent variable ‘maximum temperature’ is significant, with a Pearson correlation coefficient of approximately -0.89. The negative trend shows that the degradation of the sample tends to decelerate with the increase of maximum temperature. Therefore, the temperature warming projected for the end of the century could contribute to lessen the rate of rendered façades’ degradation in the future, in Portugal or in analogous areas of the Mediterranean. The present study is part of a methodology that is being developed to quantify the impact of changes in climate parameters on the future degradation of rendered façades. Further research is necessary regarding the degradation projections, based on the climate change signal for maximum temperatures.

Located in the heart of Porto, Portugal, the S. Bento train station is renowned worldwide for its architectural splendour and historical significance. Inaugurated in 1916, this UNESCO World Heritage Site presents stunning ceramic tile panels and architecture influenced by contemporary French design. This study presents a comprehensive historical analysis of the conservation state of S. Bento station, detailing observed anomalies, their origins, probable causes, and the maintenance and rehabilitation techniques employed over the years. Moreover, it explores the relationship between conservation practices and tourist perceptions of the station, focusing on how rehabilitation efforts influence user satisfaction. This analysis was carried out through a comprehensive sentiment analysis of over 4000 tourist reviews between 2011 and 2023, and data from the station management entity, providing insights into the effectiveness of these interventions. The research contributes to the broader discussion on heritage conservation, offering recommendations for future maintenance strategies that integrate user expectations and sentiment.

Understanding the mechanisms of pipeline failures is crucial for identifying vulnerabilities in gas transmission pipelines and planning strategies to enhance the reliability and resilience of energy supply chains. Existing studies and the American Society of Mechanical Engineers’ (ASME) Code for Pressure Piping primarily focus on corrosion, recommending inspections every 10 years to prevent incidents due to this time-dependent threat. However, these guidelines do not provide comprehensive regulation on the likelihood of incidents due to other causes, especially non-time-dependent events (i.e. do not provide any indication of the inspection frequency or the most likely time for an incident to occur). This study adopts an innovative approach adopting machine learning, particularly artificial neural networks (ANNs), to analyse historical pipeline failure data from 1970 to 2023. By analysing records from the US Pipeline Hazardous Materials Safety Administration, the model captures the complexity of various degradation phenomena, predicting failure years and hazard frequencies beyond corrosion. This innovative approach allows adopting more informed preventive measures and response strategies, offering deep insights into incident causes, consequences, and patterns. The results provide practical insights for maintenance planning, offering an estimation of periods when a pipeline may be more susceptible to incidents based on various factors. However, since all models inherently present uncertainties, both in the data and the modelling process, these estimates should be interpreted as probabilistic assessments. This study provides operators with a strategic framework to prescriptively address potential vulnerabilities, thereby promoting sustained operational integrity and minimising the occurrence of unexpected events throughout the service life of pipelines. By expanding the scope of risk assessment beyond corrosion, this study significantly advances the field of pipeline safety and reliability, setting a new standard for comprehensive incident prevention.

4%) e 94,4% dos responsáveis limpavam a boca de seus filhos, sendo a forma mais citada a escova e o creme dental (97,7%); A escovação dentária era realizada, na maioria dos casos 3 vezes ou mais vezes ao dia (55,0%).A presença de placa (IPV) e sangramento gengival (ISG) foram mais frequentes em crianças com cárie e mães com histórico de cárie tendem a apresentar filhos com cárie.

This study discusses the advantages and limitations of adopting time-based maintenance (TBM) and condition-based maintenance (CBM) strategies for natural stone claddings. In this study, an imperfect model for the system under stochastic deterioration is adopted, considering historical data about the degradation patterns of 203 natural stone claddings. This study introduces a probabilistic maintenance optimization method and a life cycle cost analysis framework to determine the optimal strategies for CBM and TBM strategies. The advantages of CBM over TBM are highlighted. CBM demonstrates the potential to achieve higher reliability levels while minimizing maintenance costs compared to TBM. CBM allows a more controlled and planned approach to maintenance, where interventions are strategically carried out based on the specific needs and condition of natural stone claddings. An optimized TBM policy is proposed, which offers a practical and reliable solution for managing the natural stone claddings. It strikes a balance between maintenance requirements, costs, and performance, ensuring the durability and performance of the claddings while minimizing unnecessary interventions.

Electric fish are good models in neuroethology as any behavior in electric fish involves both locomotor and electrical displays, which are experimentally accessible and controlled by well-known neural circuits. The agonistic behavior within the genus Gymnotus has been evaluated in Gymnotus carapo and Gymnotus omarorum, providing an advantageous model system to address comparative analyses. Gymnotus sylvius is a weakly electric fish which occurs in sympatry with G. omarorum in freshwater environments of Argentina. Here, we describe the agonistic behavior of G. sylvius in laboratory conditions. All dyads engaged in intense fights, with a latency to the first attack of 8 +/- 7.8 s and a contest phase of 42.71 +/- 31.7 s. Individual initiative in the first attack predicted contest outcome with no apparent influence of body weight asymmetry between contenders. Contenders did not escalate in their aggression during the short contest; in turn, subordinates tended to retreat in response to dominants' attacks. Submission and dominance were expressed by electric signals: dominants increased their basal electric organ discharge (EOD) rate after contest resolution, resulting in a persistent EOD rate rank. Subordinates also emitted chirps and offs during the contest and post-resolution phases without a clear temporal pattern. The agonistic behavior of G. sylvius presents some similarities with other species of the genus Gymnotus: EOD rank between dominants and subordinates, electric signals of submission, and the presence of attacks in the post-resolution phase. On the other hand, it also presents differences: a shorter evaluation phase in G. sylvius, initiative as a determinant of outcome, a higher attack rate of dominants in G. sylvius, a different temporal pattern of chirps, and different mechanisms to separate EOD rate of dominants and subordinates. These facts open a promising road to analyze the evolution of different neuroendocrine strategies, operating on homologous neural pathways, to command the same behavior.

Non-invasive vision-based approaches provide the precision and reliability required for building facade inspection. A method based on automatic image classification to detect and map the materials and anomalies in building facades is presented and compared with a traditional visual inspection and classification.

The increase in rehabilitation actions motivated further research in the scope of service life and/or building maintenance. In defining rational strategies for the buildings' maintenance, reliable tools that model their performance over time are needed. This research evaluates the impact of maintenance actions on painted renderings. More specifically, the objective of this research is to adapt and extend an existing method, evaluating new periods of service life, with and without maintenance actions, in order to be able to regionalize and expand the existing results. This research was carried out based on an extensive fieldwork survey of painted renderings of facades in vertical buildings in the city of Porto Alegre, RS, Brazil, at different times (before, during and after the execution of maintenance actions). For renderings without maintenance actions, an average service life of 14 years is obtained. After maintenance actions, especially cleaning, the estimated average service life is 16 years. After maintenance, cleaning and partial repair actions, the estimated average service life is 34 years. For painted surfaces without maintenance actions, an average service life of 10 years is estimated. After cleaning actions, the estimated average service life is 11 years. After maintenance (cleaning, partial repair actions on renderings and repainting), the average service life is 15 years, until the last period of service life that precedes the end of the rendering's life cycle.