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The evaluation of stone cladding material suitability can be a challenge due to the way that stone physical and mechanical properties, and characteristics such as mineralogy, might influence stone performance as a cladding element in a ventilated facade application. Salts can affect natural stone performance, and one of the experimental methods available to study and predict it is through accelerated aging tests such as salt fog chamber cycles. Aging test results should include the analysis of critical stone physical–mechanical properties to fully understand decay effects. The aim of this study was to reduce the lack of knowledge regarding the implications of salt fog on certain fundamental characteristics of stone cladding requirements, such as elastic properties and flexural strength, because these are particularly important properties for ventilated facade systems. A systematic methodology based on artificial salt fog cycles in a climatic chamber, microscopic analysis, weight measurement, flexural strength, and dynamic elastic modulus was performed on two limestones from Portugal: Moleanos (MO) and Semi-Rijo (SR). This study aims to contribute to improved selection stone methods linked to more sustainable stone facades, and the experimental methodology can be further applied to other stone types, particularly the ones most selected for stone cladding applications near coastal areas. In this work, results of salt fog decay cycles are presented and discussed considering their direct contribution for a better stone-cladding dimensioning process.

In the last 40 years, the National Health Service (SNS) has generated health gains that have placed Portugal at the top regarding quality of life for millions of citizens and reduced many of the inequalities in Portuguese society. We revisit the establishment of the Portuguese National Health Service and all the profound legislative changes introduced after the publication of the new Health Basic Law, the definition of the strategic axes of the SNS human resources policy and the establishment of the respective operationalization mechanisms, the approval of the new SNS Statute and the approval of the Organic and Statutes of the Executive Board of the SNS and the creation of Local Health Units (ULS) as public business entities. These legislative changes could be a fundamental step towards strengthening the construction of a fairer and more inclusive SNS, which better responds to the population’s needs through the necessary structural reforms.

Stone deterioration is significantly influenced by the process of salt crystallisation. The expansion of salt crystals on a porous framework exerts pressure on the solid fraction, causing the stone to deteriorate when the internal pressure of salt surpasses the stone’s strength. Protective coatings are employed to effectively hinder or substantially reduce the penetration of water and saline solutions. This study attempts to evaluate the effectiveness and long-term durability of limestones protected with hydrophobic coatings, focusing on their resistance to salt damage. The investigation followed the specifications set by the standard EN 12370:2019 and EN 14147:2003, which assesses the resistance of natural stone to salt crystallisation. The findings of this study indicate the conservation of physical–mechanical properties after ageing tests. In parallel, measurements of the static contact angle and the measurement of quality indexes revealed that the coatings maintained a certain level of hydrophobicity even after undergoing salt weathering tests, maintaining the good quality of the stones.

Nontechnical SummaryThe need for critical minerals for various technologies for commercial and defense use has led to a range of national policy interventions. However, many of these new laws to encourage mining, or protect local industries have not considered as scientific data on mineral reserves or the economic viability of setting specific targets. The EU’s Critical Raw Materials Act is a pivotal case in point that illustrates this challenge. We present a review of the range of laws and policies that have been set forth worldwide.Technical SummaryGrowing international conflict between countries that have large mineral production and processing capacity and those which are in demand of critical raw materials for new technologies has led to a proliferation of policies that promote resource nationalism or ‘friend-shoring’. We analyzed over 400 critical raw material policies to date that have been documented by the International Energy Agency's policy tracking tool and present the findings of the six most active jurisdictions. The EU's Critical Raw Materials Act which came into force in May 2024 stands out as the most significant legislative step taken thus far but needs better interface with environmental and social data on impacts and benefits. By analyzing the challenges faced by lithium mining projects across a range of technologies and geographic locations in Europe, we suggest the use of data generated from life cycle analyses, economic geological calculations, and ecosystem service valuation in improving the implementation of such policies and also mitigate social conflicts.Social Media SummaryThere are now more than 400 critical raw material policies worldwide, but they need to be predicated in economic and geological data to be effective.

Stones are traditionally used in construction and architectural applications as building elements due to their aesthetic and technical/structural performance. Like other environmental factors (rain, humidity, moisture, salt presence, biological activity, etc.), heating–cooling and freeze–thaw cycles significantly threaten the longevity of stone materials. Hence, considering the socio-economic and cultural value of stones, preventive actions such as hydrophobic coatings are applied to prevent or mitigate damage. The scope of this study is the performance assessment of limestones with different characteristics and the efficiency of various commercial silane/siloxane-based hydrophobic coatings when exposed to thermal variation and freeze–thaw. For that purpose, the standards EN 14066:2013 (determination of resistance to aging by thermal shock) and EN 12371:2010 (determination of frost resistance) were followed. Open porosity and static contact angles were estimated to assess the stone durability and water protection capabilities of the hydrophobics. Additionally, sound speed propagation velocity, quality of building material index, elastic modulus and flexural strength were measured to evaluate the variation of mechanical properties. Static contact angle revealed that the coatings maintained an efficient level of hydrophobicity even after thermal-shock and freeze–thaw weathering tests. The study also revealed a critical interaction between freeze–thaw cycles, hydrophobic coatings and structural integrity of the stones, mostly on more porous ones. When they are subjected to harsh environmental conditions, untreated porous limestones keep structural cohesion, allowing for the natural absorption and release of water during freezing and thawing. On the contrary, when limestones are treated, the hydrophobic coatings can moderately obstruct the water release due to the partial saturation of the porous framework by the products. It also probably resulted from the different mechanical behavior between the inner matrix and layer of stone coated, resulting in a premature breakout and mechanical damage of the stone.

The long-term endurance of building stones must be assured since their longevity has repercussions for their economic and social value. Frequently, slabs for flooring and cladding are installed with polished finishing in outdoor environments for technical and ornamental purposes in cultural heritage sites and modern civil architecture. Compared to any other finishing, glossy surfaces are rather vulnerable to wear, particularly when they interact with slightly acidic rainwater. Several hydrophobic treatments are applied to prevent this damage by preventing contact between rain and stone; such treatments are efficient but sometimes non-durable. Stakeholders and conservation scientists need better methods to anticipate the future behaviour of this building material and hydrophobic solutions. Complying with this demand, a comparison is made between outdoor natural ageing and artificial weathering, reproduced by UVA radiation, moisture and spray accelerated weathering. Artificial weathering is applied to predict the behaviour of stones over time in the real environment. Data obtained through the measurement of gloss and colour parameters, the detection of micro-textures through SEM, and the calculation of micro-roughness using a digital rugosimeter demonstrate that weakly acidic rainwater is the main cause of superficial decay of stone finishing over just six months of outdoor exposure. This period corresponds to 7–14 days of artificial weathering. Furthermore, the loss of efficiency and durability of the hydrophobic coatings is detected by measuring the static contact angle. This highlights that even if a protective treatment was proficient, it could easily deteriorate in normal weathering conditions if applied on polished, low-porosity stone. Additionally, water vapour permeability indicates variations of regular vapour transmission through the stones due to ageing. The first solution to threats is the prevention of pathologies, including aesthetic ones. A careful choice of the most suitable lithotype finish and an environmental study represent an existing solution to the problem. It must be highlighted that aesthetic requirements should not be prioritised to detriment of the technical requirements of architectural quality, performance, durability, and safety.

This paper presents the results of a laboratory simulation of a subarctic climate carried out in climatic chamber. Realistic daily and seasonal cycles of temperature of a regular subarctic continental climate without dry seasons (Dfc) were simulated and the physical/mechanical properties and performance of the slates were assessed. The slate was selected because of its use as cladding and roofing material in cold regions. Mechanical performances before and after Dfc climate simulation were evaluated through point load index, uniaxial compression, flexural strength and anchor rupture load. A decrease in these mechanical features between 9 and 50% with respect to the initial strengths has been registered. Other physical parameters such as apparent density, open porosity and water absorption were evaluated. The tests showed an increase in open porosity (+72%) and a decrease in bulk density (−0.7%). The results highlighted a predominantly physical decay and mechanical performance decreasing with a relevant lowering in strength without the detection of chemical–mineralogical alterations. Moreover, artificial sun exposure reproduced the weak solar radiation that characterizes the Dfc climate. This was carried out to assess the aesthetic characteristics of the slate, since discoloration under sun exposure was supposed to occur but the slates did not exhibit substantial color changes.

Enquadramento: O presente estudo analisa uma problemática identificada na prática profissional diária de enfermagem, sendo definido o tema “Prática clínica dos enfermeiros na prevenção da infeção associada ao cateter venoso central (CVC)”. Objetivos: Conhecer a prática clínica e o nível de conhecimentos dos enfermeiros sobre a manutenção do CVC. Metodologia: Estudo analítico e transversal, com uma metodologia quantitativa, utilizando um instrumento de recolha de dados aplicado em dezembro de 2018, através da técnica de amostragem por bola de neve, a 272 enfermeiros selecionados aleatoriamente. Resultados: Os resultados obtidos indicam altos níveis de prática clínica (90,1%) e de conhecimentos (85,7%) na realização do penso e na manutenção do CVC e que existe relação estatisticamente significativa entre a prática clínica e o nível de conhecimentos dos enfermeiros. Conclusão: Concluiu-se que a amostra apresenta um nível alto de conhecimentos acerca das normas de manutenção do CVC da prevenção da infeção e uma prática clínica que respeita, na sua maioria, as orientações dos feixes de intervenção acerca das práticas de prevenção da infeção do CVC.

The recent global warming started at the end of the 19th century, causing an increase in the average temperature of Earth and posing environmental, social, economic, and cultural repercussions. Much tangible cultural heritage is composed of natural stones, which decay due to the combination of chemical, physical, and biological factors. Biodeterioration leads to a loss of the performance requirements and socio-economic value of stone building materials. In the future, the dynamics of biodeterioration will hypothetically vary. This study aims to shed light on this variation by comparing biodeterioration under historical climatic conditions (1995–2014) with a future scenario defined by the IPCC SSP5-8.5 for the reference period 2080–2099. The material tested is Pedra de Ançã (PA), a candidate for World Heritage Stone. Climatic chambers were used to simulate the historical and predicted environmental conditions. The scope of this investigation is to understand the growth dynamic of the biodeteriogen Rhodotorula sp. and to study the morphological and aesthetic variations of stone surfaces. Biochemical and micro-topographic analyses highlighted the metabolic activity of the population proliferating under distinct environmental conditions, revealing better adaptability of Rhodotorula sp. and higher biocorrosion in the historical climate status with respect to the future.

Natural stone has been used worldwide in the construction of archaeological and historical heritage. However, its preservation continues to be threatened by weathering and degradation phenomena. Water is widely recognized as the most threatening external component that contributes to stone deterioration, increasing the need for the development of protective hydrophobic coatings to eliminate water penetration. This study intends to contribute to the better understanding of natural stone treatment strategies to prevent water penetration and subsequent stone alteration by studying the effect of coating and stone substrate temperatures, and the number of coating applications, on the effectiveness, compatibility, and durability of commercial hydrophobic coatings. The results obtained revealed that while more than one application increases coating hydrophobic effectiveness, it frequently leads to changes in the aesthetic appearance of natural stone, including whitening and darkening of the substrate’s original hues. Improved hydrophobic effectiveness (maximum gain of ≈ 9%) is also achieved when applying the commercial coatings at 4 °C to natural stone substrates maintained at room temperature, conditions that are feasible to be used in real life. Additionally, the commercial coating composed of silane/siloxane with modified fluorinated additives was found to be the most effective and durable hydrophobic solution.