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Sweet cherry trees are one of the most important crops worldwide, producing fruits with high economic importance due to the nutritional value and bioactive properties of cherries, providing benefits to human health. Due to the currently unstable climatic conditions, cherry cracking has become a significant problem, strongly affecting the quality and yield of cherry orchards. A cracking rate of 20–25% at harvest can render cherry production unprofitable, decreasing the commercial value of the fruit, as only the cracked ones can be sold to processing industries. This study aims to assess the impact of calcium- and seaweed-based biostimulant applications on sweet cherry quality and profitability in cv. Sweetheart. Applying 300 g hL−1 of calcium led to a significant 52% reduction in the cracking index and a substantial 136% increase in orchard yield. Similarly, applying 150 mL hL−1 of seaweed resulted in a 2% increase in fruit weight and a 3% decrease in the cracking index. Therefore, our findings suggest that calcium- and seaweed-based biostimulants could serve as novel and sustainable alternatives for orchard producers, enhancing cherry profitability and marketability. [ABSTRACT FROM AUTHOR]

This paper is devoted to identifying online teaching strategies appropriate for blended and face-to-face higher STEM (Science, Technology, Engineering, and Mathematics) education. The study is inspired by the experience gained during the COVID-19 pandemic lockdown, which forced many higher education institutions worldwide to shift abruptly to distance education and try many new tools, teaching methods, and strategies. Some of these tools and strategies were abandoned as soon as the lockdown had been lifted and the institutions returned to their regular functioning, but some of them are bound to stay. Certainly, it would be beneficial to include the most valuable of the gained skills and competences in traditional on-campus and blended courses. The study is based on an online questionnaire, addressed to the STEM faculty of the University of Aveiro, Portugal (which is an example of an institution that used to provide face-to-face instruction), whose analysis permits to derive a number of important recommendations. The results are compared with our previous work, where the students' perspectives were analyzed, and similarities and discrepancies in appreciation of the involved parties are highlighted. This work extends the body of knowledge about the impact of the COVID-19 pandemic on STEM education by examining the challenges and opportunities faced by teachers. The recommendations derived contribute to improving the learning outcomes of online STEM education in many similar institutions. [ABSTRACT FROM AUTHOR]

Asset management has been gaining momentum in both academic and industry, but is it so distinct from other existing management philosophies? This research effort discusses the relation between asset and quality management, particularly for organizations managing (public) infrastructures, to highlight the similarities and differences between both and their role towards sustainable infrastructure development. The compatibility matrix developed demonstrates that, in conceptual terms, asset and quality management are highly similar in the scope of these organizations. As such, organizations implementing formal and certified asset management systems should assess the existing processes to avoid overlaps and make the best use of the experience accumulated. It also proposed the balance between performance and risk as the metric to measure the quality (or value, adopting the asset management concept) of management decisions. The growing recognition that infrastructures exist in highly complex uncertain contexts requires changing management decisions from choosing the options with the highest expected outcome to the options with the best balance between expected outcome and potential variability of the outcome. Finally, considering sustainability as the ultimate goal, the relation between quality and asset management is linked to the need for integrated infrastructure management by analysing sustainable mobility versus sustainable transport infrastructures. [ABSTRACT FROM AUTHOR]

The urgent need to tackle the effects of global warming has led to a worldwide compromise and ever-more demanding regulations. In this respect, as an important greenhouse gas emitter, the cement industry has to implement major changes in its production processes to achieve future goals. In this perspective, low-carbon eco-efficient cement, such as the thermoactivated recycled cement from concrete waste (RCC), seem to be a promising alternative to current carbon-intensive binders, such as ordinary Portland cement (OPC). This study aimed to demonstrate the potential contribution of RCC to the reduction in the environmental impacts of the cement industry, by means of a comparative life cycle assessment of three production methods of this binder (wet (WM), dry (DM) and air clean (ACM) methods) and OPC. Overall, RCC WM did not turn out to be a good alternative to OPC, essentially owing to the amount of fuel and electricity required for washing and drying the particles before the magnetic separation. On the other hand, RCC DM and RCC ACM proved to be promising alternatives to RCC WM and OPC, with a relevant reduction in all impact categories. [ABSTRACT FROM AUTHOR]

Cities face increasing water pressure and supply issues, jeopardizing the balance between growth and sustainable water resource use. Green, resilient, smart, circular, blue, water sensitive, or water-wise city concepts are increasingly part of the design of strategies to rethink cities. These concepts have motivated many studies, but little is known about their relative relevance among the scientific community and how they consider water circularity. The objective of this study is to assess how these city concepts incorporate water circularity principles. The assessment is based on a bibliometric analysis of scientific articles recently published. The findings show that despite the wide number of articles dedicated to the various city concepts, water circularity-related challenges are still a small niche of concern, strongly driven by European authors. Moreover, our study showed that water circularity principles are not equally considered among the different city concepts. This uneven assimilation of principles in influential city concepts unveiled gaps regarding water circularity. This brings a new perspective to the use of more integrated definitions, highlighting the importance of such principles in the future use of these concepts when envisioning roadmaps toward sustainable water use in cities. [ABSTRACT FROM AUTHOR]

The Paiva River is a tributary of the Douro River in northern Portugal with a length of 110 km and a catchment area of 790 km² . Nowadays, its upper section dries completely by the end of the dry season every year. The individuals living in communities along the river are consistent in identifying the beginning of this phenomenon by the end of the 1990 s or early 2000 s. In the present research, the potential causes for this are identified, evaluated, and discussed. The direct human consumption was possible to exclude due to the decrease of both population and water-intensive activities in the period of interest. Considering the information available, climate changes are identified as the main driver for the complete dry out of the upper section. Specifically, the differences in the precipitation distribution along the year were found to be statistically significant and the increase of the number of consecutive days without rain could be related to the depletion of the underground water. Considering rainfall pattern forecasts for 2050 based on various climate change scenarios and global circulation models, it is possible to conclude that the already poor environmental condition of the upper Paiva River section will degrade even further in the future. [ABSTRACT FROM AUTHOR]

The present article proposes a methodology to consider the uncertainty intrinsic to data-based models when comparing their performance. The goal is to provide a quantification of the variability of this type of models due to the random nature of the calibration process and enable a statistical comparison of the models' performance when attempting to identify the best. The methodology proposed doesn't provide an alternative metric to determine the models' performance, but it expands the traditional deterministic comparison to a stochastic comparison. The methodology builds on the current standard approach for developing data-based model and its application is demonstrated to model sewer condition using data from 4 trunk sewers of the SANEST – Saneamento da Costa do Estoril sewer system, corresponding to 25 km of sewer pipes. The data-based models were developed using artificial neural networks, support vector machines, bootstrapping aggregation and least squares support vector machines. For the case study, the highest and average misclassification performance records are similar for all models (23% to 24% and 31% to 33%, respectively) but the lowest performance varied more significantly (39% to 62%). This demonstrates that selecting a model based on its maximum single realisation performance alone may be misleading. [ABSTRACT FROM AUTHOR]

Extensive research has been carried out on waste collection costs mainly to differentiate costs of distinct waste streams and spatial optimization of waste collection services (e.g. routes, number, and location of waste facilities). However, waste collection managers also face the challenge of optimizing assets in time, for instance deciding when to replace and how to maintain, or which technological solution to adopt. These issues require a more detailed knowledge about the waste collection services’ cost breakdown structure. The present research adjusts the methodology for buildings’ life-cycle cost (LCC) analysis, detailed in the ISO 15686-5:2008, to the waste collection assets. The proposed methodology is then applied to the waste collection assets owned and operated by a real municipality in Portugal (Cascais Ambiente – EMAC). The goal is to highlight the potential of the LCC tool in providing a baseline for time optimization of the waste collection service and assets, namely assisting on decisions regarding equipment operation and replacement. [ABSTRACT FROM AUTHOR]

Modeling the service life of building components is a key requirement for several purposes, including the implementation of an effective and efficient asset-management system, life-cycle assessments, or life-cycle cost calculations. Because the phenomena underlying the degradation of building components is highly complex, it is common to use statistical approaches for modeling purposes. This paper is focused on the statistical modeling of the service life of the wood frame doors and windows of the National Palace of Sintra. A review of the main factors of degradation of traditional linseed-based painted wood frame doors and windows and of the approaches that have been used to model the service life of building materials and components is presented. The influence of the exposure to weather agents on the degradation rate of external wood frame doors and windows is investigated and a model to estimate the average condition level is proposed. The proposed model takes into account radiation and wind-driven rain and their interaction in the degradation process. [ABSTRACT FROM AUTHOR]

The nonaerated region may occupy a large portion of the skimming flow in steep, stepped spillways, particularly for relatively high unit flow rates. In spite of the numerous contributions on the hydraulic properties at both the inception point of air entrainment and the aerated region, much less is known regarding the flow in the nonaerated region. In this paper, new empirical evidence, based on an extensive data set obtained during several years in a large-scale facility, sheds light on the features of the nonaerated-flow region. Diverse ways to locate and estimate the main hydraulic properties at the inception point are first discussed and compared. Then, expressions capable of characterizing the main flow variables along the nonaerated region are presented, namely, the boundary-layer development, the velocity distribution, the equivalent clear-water depth, the characteristic depth taking into account the free-surface unsteadiness due to turbulence, and the energy dissipation. The energy dissipation is observed to be larger than that for smooth spillways, although much smaller than values typically reported for aerated flows at the toe of stepped spillways. [ABSTRACT FROM AUTHOR]

Traditionally, research on stepped spillway hydraulics has been focused on the air-water flow region but for the hydraulic design of small embankment dams experiencing relatively large overtopping flows, the nonaerated region can be very important. Empirical formulas are presented for predicting skimming flow properties upstream of the point of inception of air entrainment for 1V:2H sloping stepped spillways, and the location and flow depth at the point of inception. Particular emphasis is placed on the clear-water depth, velocity distribution, and the energy dissipation characteristics in the developing nonaerated flow region. The velocity distribution is well described by a power law. The normalized clear-water depth and the normalized specific energy varied with the relative distance along the spillway and the effect of the normalized critical depth was negligible. Finally, the rate of energy dissipation was small, which has direct implications for the design of the downstream energy dissipator. [ABSTRACT FROM AUTHOR]

For the majority of the contractual arrangements used in construction projects, the owner is not responsible for the cost deviations due to the variability of labor productivity or material price, amongst many other aspects. Consequently, the cost performance of a project may be entirely distinct for the owner and the contractor. Since the majority of quantitative research on cost estimation and deviation found in the literature adopts the owners' perspective, this research provides a contribution towards modeling costs and cost deviation from a contractor's perspective. From an initial sample of 13 residential buildings and 10 office building projects, it was possible to develop models for cost estimation at the early stage of development, including both endogenous and exogenous variables. Although the sample is relatively small, the authors were able to fully analyze all the cost data, using no secondary sources of data (which is very frequent in cost modeling studies). The statistically significant variables in the cost estimation models were the areas above and below ground and the years following the 2008 financial crisis, including the international bailout (2011–2014) period. For estimating the unit cost, a nonlinear model was obtained with the number of underground and total floor, the floor ratio, and the years following the 2008 financial crisis, including the international bailout (2011–2014) period as predictors. For the office buildings, a statistically significant correlation was also found between the cost deviation and number of underground floors. [ABSTRACT FROM AUTHOR]

The article presents a response from the authors to a discussion on their paper "Air entrainment onset in skimming flows on steep stepped spillways: an analysis." They argue that their experiments were not influenced by shockwaves, irrespective of flow conditions. They also comment on the discussers' view that an inlet coefficient (Eqs (D3) and (D4)) may be considered in the event of shockwave effects as in the experiments by J.H. Wu and colleagues.