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Changes in weather patterns pose a threat to the serviceability and long-term performance of roads, and porous asphalt (PA) roads are particularly sensitive to the freezing-thawing (FT) phenomenon. The main objective of this research is to assess the impact of climate change, particularly freezing and thawing cycles, on PA. Climate models predict changes in air temperature, not pavement temperature. To predict the climate change impact on pavements performance, this requires first establishing a relationship between air and road temperature and a correlation between pavement performance and FT cycles. This project focuses on the Netherlands, where PA pavement use has become mandatory, and recent severe winters have increased the discussion about the cold weather performance of porous asphalt and the potential challenges of changing winter weather patterns. When considering long-term changes in climate, the cost impacts of freeze-thaw on PA pavement are predicted to vary regionally and in most areas reach a point in the middle of the century when a reactive wait-and-see approach is more advantageous than proactive adaptation. Further research is suggested to refine the relationship between observed damage and freeze-thaw impacts on PA pavement.

An experiment in open-top chambers was carried out in summer 2008 in Curno (northern Italy) in order to study the effects of ozone and drought stress on net photosynthesis, growth and stable isotope partitioning on cuttings of an ozone-sensitive poplar clone (Oxford). The biomass (as dry weight) of stems, leaves and roots was assessed five times during the growing season on a set of plants intended for destructive measurements (set 1). Another set of plants (set 2) was used for repeated measurements (net photosynthesis) and then destroyed at the end of the experiment. The dry weight of the stems in set 1 plants was calculated using allometric relations. The results showed that drought stress had a strong effect on all the parameters assessed. Ozone did not have any effect on biomass allocation in woody stems and stable isotope composition but reduced root/shoot ratios and caused loss of leaves during the growing season. The loss of leaves in the lower part of the crown was partly recovered with the emission of new young leaves in the upper part, thus restoring the overall photosynthetic apparatus. We conclude that the metabolic costs suffered to repair damage and support growth, and the reduction in starch reserves in the roots can compromise growth and the capacity to cope with stress factors in subsequent years.

The potential of renewable energy should be fully exploited in the transportation sector to achieve a cleaner production. Therefore, this paper proposes an on-grid hybrid hydrogen refueling and battery swapping station powered by wind energy. This novel concept can promote the development of low-carbon emission vehicles including hydrogen-based vehicle and battery electric vehicle. During the daily operation of the station, the multiple uncertainties may lead to a higher operational cost. To address this problem, a hybrid stochastic/distributionally robust optimization method is proposed to handle different uncertainties for the energy management problem. The first type of uncertainties can be depicted by a certain distribution, i.e. electricity price and wind power, which is processed by a stochastic optimization method. The second type of uncertainties is associated with human behaviors and is difficult to find its probability distribution, i.e. the hydrogen demand of hydrogen-based vehicles, so the second type is processed by a distributionally robust optimization method. The overall objective is to minimize the total operational cost of the station, which also considers the battery swapping station overstock punishment. Because a reasonable battery swapping scheduling can reduce the waiting time of users and operational cost of the station. The results indicate that the proposed method can effectively address the conservatism of solutions as its total operational cost is 4.4% lower than that of the hybrid stochastic/robust optimization method under a high confidence level.

Abstract The implementation of energy efficiency measures is an effective way to gain energy savings in the Italian residential sector. This paper assesses the embodied energy impact related to the envelope insulation and evaluates the energy and carbon payback of the efficiency measures. The proposed method consists of (1) an estimation of the baseline operational energy consumption, (2) simulations of realistic retrofit solutions and, (3) the assessment of the ‘retrofitting’ embodied energy and the energy and carbon payback time calculation. The payback is based on the comparison between the saved operational energy and the embodied energy of the materials selected for insulation. Ten Italian cities are analysed, and the results show a deep dependence on the climate zone. In Northern Italian cities, envelope insulation gains relevance as the energy and carbon payback periods are shorter, about 3 years against the 84 years for the Southern city of Palermo. The optimal thickness is estimated for the city of Milan considering the building’s typology, the insulation materials, and the energy payback. This study shows how the total energy savings can be used as a criterion to obtain design indications.

Antiprotons have been suggested as a possibly superior modality for radiotherapy, due to the energy released when antiprotons annihilate, which enhances the Bragg peak and introduces a high-LET component to the dose. However, concerns are expressed about the inferior lateral dose distribution caused by the annihilation products.We use the Monte Carlo code FLUKA to generate depth-dose kernels for protons, antiprotons, and carbon ions. Using these we then build virtual treatment plans optimized according to ICRU recommendations for the different beam modalities, which then are recalculated with FLUKA. Dose-volume histograms generated from these plans can be used to compare the different irradiations.The enhancement in physical and possibly biological dose from annihilating antiprotons can significantly lower the dose in the entrance channel; but only at the expense of a diffuse low dose background from long-range secondary particles. Lateral dose distributions are improved using active beam delivery methods, instead of flat fields.Dose-volume histograms for different treatment scenarios show that antiprotons have the potential to reduce the volume of normal tissue receiving medium to high dose, however, in the low dose region antiprotons are inferior to both protons and carbon ions. This limits the potential usage to situations where dose to normal tissue must be reduced as much as possible.

Enhanced weathering (EW) is one of the most promising negative emissions technologies urgently needed to limit global warming to at least below 2 °C, a goal recently reaffirmed at the UN Global Climate Change conference (i.e., COP26). EW relies on the accelerated dissolution of crushed silicate rocks applied to soils and is considered a sustainable solution requiring limited technology. While EW has a high theoretical potential of sequestering CO2, research is still needed to provide accurate estimates of carbon (C) sequestration when applying different silicate materials across distinct climates and major soil types in combination with a variety of plants. Here we elaborate on fundamental advances that must be addressed before EW can be extensively adopted. These include identifying the most suitable environmental conditions, improving estimates of field dissolution rates and efficacy of CO2 removal, and identifying alternative sources of silicate materials to meet future EW demands. We conclude with considerations on the necessity of integrated modeling-experimental approaches to better coordinate future field experiments and measurements of CO2 removal, as well as on the importance of seamlessly coordinating EW with cropland and forest management.

AbstractBackground: Chlorhexidine (CHX) 0.2% solution is still “the leading oral antiseptic” for controlling gingivitis. Side effects, however, limit the acceptability to users and the long‐term employment of a 0.2% CHX antiseptic in preventive dentistry. This stimulated the development of new formulations. The aim of the present study was to assess the effect on plaque inhibition and taste perception of two commercially available mouthrinses (0.12% CHX non‐alcohol base with 0.05% cetyl pyridinium chloride (Cpc) versus 0.2% CHX alcohol base).Methods: The study was designed as a single‐blind, randomized two group parallel experiment, to compare two different commercially available mouthrinses, during a 3‐day plaque accumulation model. Forty healthy volunteers were enrolled in the study and received a thorough dental prophylaxis at the beginning of the test period. Over a 72‐h experimental non‐brushing period, during which subjects abstained from all forms of mechanical oral hygiene, one group (test) used a 15 ml alcohol free 0.12% CHX (=18 mg) mouthrinse on a Cpc base (Perioaid®, CHX⊕Cpc), twice daily for 30 s. The other group (control) used a 10 ml 0.2% CHX (=20 mg) mouthrinse on an 11.8% ethanol alcohol base (Corsodyl®, CHX⊕Alc), twice daily for 60 s. After 72 h of plaque formation, the amount of plaque was evaluated. By the use of visual analogue scale, the subjects were asked for their appreciation of the taste of the mouthrinse they had used.Results: The mean plaque index for the CHX⊕Cpc group was 0.97 and for the CHX⊕Alc group 0.78. After 72 h of non‐brushing, there was no significant difference in plaque accumulation between the two groups. The answers to the questions (taste perception and after‐taste) showed a statistically significant difference between the two groups. The mean visual analogue scale (VAS) scores for taste appreciation on a scale from very bad to very good taste (0–10) were 5.92 for the CHX⊕Cpc group and 4.10 for the CHX⊕Alc group (p=0.02). The mean visual analogue scale (VAS) scores for the after‐taste on a scale from very short to very long (0–10) were 7.24 for the CHX⊕Cpc group and 5.38 for the CHX⊕Alc group.Conclusions: Within the limitations of the present study design, it can be concluded that rinsing with a 0.12% CHX mouthrinse on a non‐alcohol base with 0.05% Cpc (Perio‐Aid®) is not significantly different from rinsing with a 0.2% CHX mouthrinse on an alcohol base (Corsodyl®). It appears that the subjects appreciated the taste of the non‐alcohol CHX solution better but the after‐taste of the rinse remained longer in the mouth.