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Portugal made a climate commitment when it ratified the Paris Climate Agreement in 2015. As a result, Portugal, along with other EU members, has created a national roadmap for the deployment of hydrogen as a crucial component of Portugal's energy transition towards carbon neutrality, creating synergies between the electric and gas systems. The increased variability of generation from variable renewable power sources will create challenges regarding the security of supply, requiring investment in storage solutions to minimize renewable energy curtailment and to provide dispatchability to the electric power system. Hydrogen can be a renewable energy carrier capable of ensuring not only the desired transformation of the infrastructures of the gas system but also an integrator of the Electric System, such as in Power-to-Power (P2P) systems. Hydrogen can be produced with a surplus of renewable electricity from wind and solar, allowing a long-term energy seasonal storage strategy, namely by using underground salt caverns, to be subsequently transformed into electricity when demand cannot be supplied due to a shortage of renewable generation from solar or wind. P2P investments are capital intensive and require the development of transitional regulation mechanisms to both create opportunities to market agents while fostering the energy surplus valuation and decreasing the energy dependency. In order to maintain the electric system's security of supply, the suggested methodology innovatively manages the importance of seasonal storage of renewable energy surplus using hydrogen in power systems. It suggests a novel set of regulatory strategies to foster the creation of a P2P solution that maintains generation adequacy while assisting in decarbonising the electric power industry. Such methodology combines long-term adequacy assessment with regulatory framework evaluation to evaluate the cost of the proposed solutions to the energy system. A case study based on the Portuguese power system outlook between 2030 and 2040 demonstrates that the considerable renewable energy surplus can be stored as hydrogen and converted back into electricity to assure adequate security of supply levels throughout the year with economic feasibility under distinct public policy models. • Sector coupling emerges as a solution to accelerate energy transition, harvesting renewable energy surplus with P2P assets • Although with a decreasing trend, thermal firm capacity will still secure considerable load until 2040 while keeping SoS • P2P, together with H2 seasonal storage, can ensure adequate SoS indexes and further increase renewable energy integration • Transitional regulation must be developed to foster P2P projects [ABSTRACT FROM AUTHOR]

Abstract: The application of gas mass-flow meters (GMFM) sensors needs the knowledge of its measurement model and measurement uncertainties. It was already known that the GMFM output model depends on gas mass-flow and gas composition. In this work, different throughput GMFM sensors were used for different gas flow rates and gas composition in order to verify and to improve the GMFM measurement model. A direct calibration procedure and a dynamic volumetric method were applied both to get the measurement model and to evaluate the performance of gas sensors and GMFM sensors against certified reference materials and suitable standards. Additionally, the obtained data were used both to calculate the uncertainties of gas mass-flow measurement and to improve the GMFM gas response factors. The calculated uncertainties of the GMFM direct measurement was approximately 2% of the measured value. The uncertainty of the dynamic volumetric method developed in this work was found as approximately 5% of the measured value and that was mainly influenced by the uncertainties of the standards used. [Copyright &y& Elsevier]

Background: Rheumatoid arthritis (RA) is a chronic, systemic inflammatory disorder. There is a clear association between some disease-modifying drugs used to treat RA and infection. The introduction of the anti-tumor necrosis factor (TNF) therapies has improved the outcome of severe RA. The TNF-antagonism may increase susceptibility to granulomatous pathogens such as Mycobacterium tuberculosis, Listeria monocytogenes, and Histoplasma capsulatum. Methods: We report the case of a 37-year-old woman with RA receiving an anti-TNF agent, who developed a rash on her back and both legs, which was finally diagnosed as tuberculoid leprosy. Results: This is the first case of leprosy due to anti-TNF therapy reported in Europe. Conclusions: Clinicians should be aware of this and other types of atypical and serious infections that patients may suffer from when treated with anti-TNF agents. [Copyright &y& Elsevier]

Postprandial hyperglycemia induces vascular endothelial dysfunction (VED) and increases future cardiovascular disease risk. We hypothesized that postprandial hyperglycemia would decrease vascular function in healthy men by inducing oxidative stress and proinflammatory responses and increasing asymmetric dimethylarginine:arginine (ADMA:arginine), a biomarker that is predictive of reduced NO biosynthesis. In a randomized, cross-over design, healthy men (n = 16; 21.6 ± 0.8 y) ingested glucose or fructose (75 g) after an overnight fast. Brachial artery flow-mediated dilation (FMD), plasma glucose and insulin, antioxidants, malondialdehyde (MDA), inflammatory proteins, arginine, and ADMA were measured at regular intervals during the 3-h postprandial period. Baseline FMD did not differ between trials (P > 0.05). Postprandial FMD was reduced following the ingestion of glucose only. Postprandial MDA concentrations increased to a greater extent following the ingestion of glucose compared to fructose. Plasma arginine decreased and the ratio of ADMA:arginine increased to a greater extent following the ingestion of glucose. Inflammatory cytokines and cellular adhesion molecules were unaffected by the ingestion of either sugar. Postprandial AUC(0-3 h) for FMD and MDA were inversely related (r = -0.80; P < 0.05), suggesting that hyperglycemia-induced lipid peroxidation suppresses postprandial vascular function. Collectively, these findings suggest that postprandial hyperglycemia in healthy men reduces endothelium-dependent vasodilation by increasing lipid peroxidation independent of inflammation. Postprandial alterations in arginine and ADMA:arginine also suggest that acute hyperglycemia may induce VED by decreasing NO bioavailability through an oxidative stress-dependent mechanism. Additional work is warranted to define whether inhibiting lipid peroxidation and restoring arginine metabolism would mitigate hyperglycemia-mediated decreases in vascular function. [ABSTRACT FROM AUTHOR]

Abstract: Vitamin C supplementation has been suggested to reduce cardiovascular disease risk. However, no studies have examined the relationship between vitamin C status and vascular dysfunction in lean and obese individuals in the absence of supplementation. We examined whether vascular function is interrelated with vitamin C status and inflammation in healthy, college-aged lean and obese men with no history of dietary supplementation. A cross-sectional study was conducted during winter 2008 in lean and obese men aged 21±3 years (n=8/group). Brachial artery flow-mediated dilation (FMD) was measured to determine vascular endothelial function. Plasma antioxidants (vitamin C, vitamin E, and thiols), inflammatory proteins (C-reactive protein [CRP], myeloperoxidase [MPO], and cytokines), and cellular adhesion molecules were measured. Participants also completed 3-day food records on the days preceding their vascular testing. Group differences were evaluated by t tests, and correlation coefficients were determined by linear regression. FMD was 21% lower (P<0.05) in obese men. They also had 51% lower vitamin C intakes and 38% lower plasma vitamin C concentrations. Obese men had greater plasma concentrations of CRP, MPO, inflammatory cytokines, and cellular adhesion molecules. Participants'' CRP and MPO were each inversely related (P<0.05) to FMD (r=−0.528 and −0.625) and plasma vitamin C (r=−0.646 and −0.701). These data suggest that low vitamin C status is associated with proinflammatory responses and impaired vascular function in lean and obese men. Additional study is warranted to determine whether improving dietary vitamin C intakes from food attenuate vascular dysfunction. [Copyright &y& Elsevier]

Abstract: Gas mass-flow meters (GMFM) for original equipment manufacturers (OEM) applications are presently found in a relatively easy and cheap way. GMFM may be applied in a number of different situations but technical information concerning its principles of measurement and applications is still misleading. In this paper, the principles of GMFM measurement are discussed and the operating parameters are clarified. A concept of gas mass-flow response factor is introduced and further used in a model for gas mass-flow measurement that is suitable to any gas mixture of known composition. In addition, a model for the application of GMFM to dynamic volumetric methods of dilution is presented and generalized. [Copyright &y& Elsevier]

Abstract: This paper presents an application of probabilistic methodologies to evaluate the reserve requirements of generating systems with a large penetration of renewable energy sources. The idea is to investigate the behavior of reliability indices, including those from the well-being analysis, when the major portion of the renewable sources comes from wind power and other intermittent sources. A new simulation process to address operating reserve adequacy is introduced, and the correspondent reliability indices are observed. Case studies on the Portuguese and Spanish generating systems are presented and discussed. [Copyright &y& Elsevier]

Abstract: Reserve definition is a compromise between economic issues (additional capacity costs) and reliability (risk of loss of load due to outages of the generators), generally approached by deterministic criteria (e.g. the percentage rule defined by UCTE in Europe) and probabilistic methods like PJM (Pennsylvania–New Jersey, Maryland) and its enhancements, based on the concept of risk. With wind power generation increasing in power systems worldwide, these operational issues gain a renewed interest due to the volatile nature of this kind of energy. The aim of this paper is therefore to address this issue from a risk evaluation point of view, showing that it is possible to extend classical probabilistic methods to this new situation, by introducing a detailed Markov model of wind parks that accounts both for machine failures and different wind power levels. This evaluation, where wind generation fluctuation and uncertainty is included, can be helpful for transmission system operators (TSO), when defining the reserve requirements for the next hours. In fact, the results obtained for the risk can be used by TSO to check if the reserve levels that results from traditional deterministic rules are acceptable or need to be increased. [Copyright &y& Elsevier]

Abstract: In the scope of the discussions about microgeneration (and microgrids), the avoided electrical losses are often pointed out as an important value to be credited to those entities. Therefore, methods to assess the impact of microgeneration on losses must be developed in order to support the definition of a suitable regulatory framework for the economic integration of microgeneration on distribution networks. This paper presents an analytical method to quantify the value of avoided losses that microgeneration may produce on LV networks. Intervals of expected avoided losses are used to account for the variation of avoided losses due to the number, size and location of microgenerators, as well as for the kind of load distribution on LV networks. [Copyright &y& Elsevier]

Abstract: The emergence of microgeneration has recently lead to the concept of microgrid, a network of LV consumers and producers able to export electric energy in some circumstances and also to work in an isolated way in emergency situations. Research on the organization of microgrids, control devices, functionalities and other technical aspects is presently being carried out, in order to establish a consistent technical framework to support the concept. The successful development of the microgrid concept implies the definition of a suitable regulation for its integration on distribution systems. In order to define such a regulation, the identification of costs and benefits that microgrids may bring is a crucial task. Actually, this is the basis for a discussion about the way global costs could be divided among the different agents that benefit from the development of microgrids. Among other aspects, the effect of microgrids on the reliability of the distribution network has been pointed out as an important advantage, due to the ability of isolated operation in emergency situations. This paper identifies the situations where the existence of a microgrid may reduce the interruption rate and duration and thus improve the reliability indices of the distribution network. The relevant expressions necessary to quantify the reliability are presented. An illustrative example is included, where the global influence of the microgrid in the reliability is commented. [Copyright &y& Elsevier]

Stress-related cardiomyopathy is underdiagnosed in the white population. Recently, an increasing awareness of this syndrome was noted in the United States. Stress-related cardiomyopathy was found mostly in women after an immediate stress. The available literature has indicated excellent short-term prognosis and full recovery. We report the case of a 56-year-old white woman with acute pancreatitis, whose condition necessitated an endoscopic retrograde cholangiopancreatography procedure. Shortly after she received counseling for this procedure, acute retrosternal chest pain and shortness of breath developed. She had ischemic abnormalities on electrocardiography and mild cardiac biomarkers elevation. Subsequent cardiac catheterization revealed normal coronary arteries but reduced ejection fraction (25%), and typical apical ballooning was noted. Ten days later, the left ventricular function completely normalized (ejection fraction of 55%). [Copyright &y& Elsevier]

• Robust Power-Flow solvers able to efficiently handle ill-conditioned systems. • Issues related with the computational efficiency or the robustness properties. • Modifications about the standard structure of the Continuous Newton's method. • The suggested modifications allow to overcome the drawbacks. This paper tackles the efficient Power-Flow solution of ill-conditioned cases. In that sense, those methods based on the Continuous Newton's philosophy look very promising, however, these methodologies still present some issues mainly related with the computational efficiency or the robustness properties. In order to overcome these drawbacks, we suggest several modifications about the standard structure of the Continuous Newton's method. Thus, the standard Continuous Newton's paradigm is firstly modified with a frozen Jacobian scheme for reducing its computational burden; secondly, it is extended for being used with High-order Newton-like method for achieving higher convergence rate and, finally, a regularization scheme is introduced for improving its robustness features. On the basis of the suggested improvements, a Power-Flow solution paradigm is developed. As example, a novel Power-Flow solver based on the introduced solution framework and the 4th order Runge-Kutta formula is developed. The novel technique is validated in several realistic large-scale ill-conditioned systems. Results show that the suggested modifications allow to overcome the drawbacks presented by those methodologies based on the Continuous Newton's method. On the light of the results obtained it can be also claimed, that the developed solution paradigm constitutes a promising framework for developing robust and efficient Power-Flow solution techniques. [ABSTRACT FROM AUTHOR]

Tobacco is the most widespread non-food crop in the world. In Brazil, tobacco cultivation is one of the main commodities of the southern region. However, its production is associated with environmental impacts and risks to human health, which have yet to be quantified. This paper uses midpoint and endpoint life cycle assessment (LCA) to analyze the potential environmental damage and human health risk associated with agricultural production of conventional Virginia (CV), organic Virginia (OV), and Burley (BU) tobacco varieties. Organic tobacco production substitutes synthetic fertilizers and pesticides with organic compounds in the cropping stage. The results show that for one ton of dried tobacco, BU, CV, and OV emit 1,610, 1,426, and 1,091 kg CO 2 eq, respectively. For organic production, greater impacts are linked to the land use (LU) impact category. The endpoint results showed that OV production resulted in a higher potential for human and environmental damage than BU and CV. The drying of green OV and CV tobacco requires the burning of firewood, which emits high levels of particulate matter and is associated with human health (HH) damage. Overall, the HH damage category accounts for 68%, 82%, and 78% of the total score points associated with the production of BU, CV, and OV. Image 1 • Life Cycle Assessment of 3 tobacco varieties in Southern Brazil was performed. • Burley variety was the foremost environmentally sustainable production. • The organic tobacco has highest environmental damage. • Conventional Virginia has the minor land use because its higher productivity. • PM2.5 emitted during leaf drying affects the most human health. Along with tobacco consumption, conventional and organic agricultural tobacco production is also associated with significant environmental impacts and risks to human health. [ABSTRACT FROM AUTHOR]

This paper addresses the problem faced by an aggregator of small prosumers, when participating in the energy market. The aggregator exploits the flexibility of prosumers’ appliances, in order to reduce its market net costs. Two optimization procedures are proposed. A two-stage stochastic optimization model to support the aggregator in the definition of demand and supply bids. The aim is to minimize the net cost of the aggregator buying and selling energy at day-ahead and real-time market stages. Scenario-based stochastic programing is used to deal with the uncertainty of electricity demand, end-users’ behavior, outdoor temperature and renewable generation. The second optimization is a model predictive control method to set the operation of flexible loads in real-time. A case study of 1000 small prosumers from the Iberian market is used to compare four day-ahead bidding strategies and two real-time control strategies, as well as the performance of combined day-ahead and real-time strategies. The numerical results show that the proposed strategies allow the aggregator to reduce the net cost by 14% compared to a benchmark typically used by retailers (inflexible strategy). [ABSTRACT FROM AUTHOR]

Near-future electric distribution grids operation will have to rely on demand-side flexibility, both by implementation of demand response strategies and by taking advantage of the intelligent management of increasingly common small-scale energy storage. The Home energy management system (HEMS), installed at low voltage residential clients, will play a crucial role on the flexibility provision to both system operators and market players like aggregators. Modeling and forecasting multi-period flexibility from residential prosumers, such as battery storage and electric water heater, while complying with internal constraints (comfort levels, data privacy) and uncertainty is a complex task. This papers describes a computational method that is capable of efficiently learn and define the feasibility flexibility space from controllable resources connected to a HEMS. An Evolutionary Particle Swarm Optimization (EPSO) algorithm is adopted and reshaped to derive a set of feasible temporal trajectories for the residential net-load, considering storage, flexible appliances, and predefined costumer preferences, as well as load and photovoltaic (PV) forecast uncertainty. A support vector data description (SVDD) algorithm is used to build models capable of classifying feasible and non-feasible HEMS operating trajectories upon request from an optimization/control algorithm operated by a DSO or market player. [ABSTRACT FROM AUTHOR]

A decision-making approach based on multi-criteria techniques can help to make the massive deployment of the microgrid concept a viable solution, potentially leading to proper incentive mechanisms for distribution system operators, microgeneration owners and loads. [ABSTRACT FROM AUTHOR]

Abstract: Due to its combinatorial nature, the Unit Commitment problem has for long been an important research challenge, with several optimization techniques, from exact to heuristic methods, having been proposed to deal with it. In line with one current trend of research, metaheuristic approaches have been studied and some interesting results have already been achieved and published. However, a successful utilization of these methodologies in practice, when embedded in Energy Management Systems, is still constrained by the reluctance of industrial partners in using techniques whose performance highly depends on a correct parameter tuning. Therefore, the application of metaheuristics to the Unit Commitment problem does still justify further research. In this paper we propose a new search strategy, for Local Search based metaheuristics, that tries to overcome this issue. The approach has been tested in a set of instances, leading to very good results in terms of solution cost, when compared either to the classical Lagrangian Relaxation or to other metaheuristics. It also drastically reduced the computation times. Furthermore, the approach proved to be robust, always leading to good results independently of the metaheuristic parameters used. [Copyright &y& Elsevier]

In the present work, we studied the effect of cholesterol/phospholipid (CH/PL) molar ratio on aluminum accumulation and aluminum-induced alteration of membrane fluidity in rat brain cortex synaptosomes. We observed that sub-acute (daily supply of 1.00 g of AlCl3 during 10 days) and chronic (daily supply of 0.03 g of AlCl3 during 4 months) exposure to dietary aluminum leads to a synaptosomal aluminum enrichment of 45 and 59%, respectively. During chronic exposure to AlCl3, the enhancement of aluminum content was prevented by administration of colestipol (0.31 g/day), which decreased the synaptosomal membrane CH/PL molar ratio (nmol/nmol) from 1.2 to 0.4. Fluorescence anisotropy analysis, using 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1-(4-(trimethylamino)phenyl)-6-phenylhexa-1,3,5-triene (TMA–DPH), showed that after treatment with colestipol a decrease in membrane order occurs at the level of hydrophilic lipid–water surface and deeper hydrophobic region of the synaptosomal membrane. When the rats were exposed to aluminum, it was observed a significant enhancement of membrane fluidity, which was more pronounced at the level of the membrane hydrophilic regions. Meanwhile, when chronic exposure to dietary AlCl3 was accompanied by treatment with colestipol, the aluminum-induced decrease in membrane order was negligible when compared to TMA–DPH and DPH anisotropy values measured upon colestipol treatment. In contrast, in vitro incubation of synaptosomes (isolated from control rats) with AlCl3 induced a concentration-dependent rigidification of this more hydrophilic membrane region. The opposite action of aluminum on synaptosomal membrane fluidity, during in vivo and in vitro experiments, appears to be explained by alteration of synaptosomal CH/PL molar ratio, since a significant reduction (∼80%) of this parameter occurs during in vivo exposure to aluminum. In conclusion, during in vivo exposure to aluminum, fluidification of hydrophilic regions and reduction of CH/PL molar ratio of presynaptic membranes accompany the accumulation of this cation, which appear to restrict aluminum retention in brain cortex nerve terminals. [Copyright &y& Elsevier]

Functional and healthier foods has been seen as important elements in a healthier lifestyle. In order to obtain these products, reformulation is the main strategy to develop health-oriented solutions. In addition to the health benefits, increasing evidence have been suggesting that functional foods can also influence satiety, a major factor related to the frequency of food consumption and, consequently, the health. The aim of this review is to discuss the current evidence associating the consumption of functional foods with satiety. The studies with healthier and functional food products disclose the relation between protein, dietary fiber, fat, sugar, and salt with satiety. Satiety is a complex and dynamic process that can be modified, at some extent, with food ingredients. Increasing dietary fiber and modifying fat and sugar composition are the main strategies to obtain healthier and functional foods with increased satiating effect. Major advances are still necessary to optimize the satiety of products with high protein content and clarify the relation between salt and satiety. • Functional foods can be of great aid to improve satiety. • Protein rich and low sugar foods and beverages has similar satiety. • Increasing DF in beverages, baked and dairy products enhance satiety. • Health-oriented fat reformulation can increase satiety in many products. [ABSTRACT FROM AUTHOR]

• MSW community composting is more economically feasible than anaerobic digestion. • The MSW tariff will cost 3.5–10.8 R$·inhabitant−1·month−1. • MSW collection and transport represent about 60% of the total cost of an MSWMF. • An MSWMF with an 8% IRR will return the investors' capital in about 10 years. Municipal solid waste (MSW) management in dense urban areas is a challenge for municipalities, especially in developing countries, which commonly have deficient waste management. For example, the metropolitan region of Goiás State, Brazil, has 19 municipalities that dispose of about 72.5% of total MSW in unlicensed MSW final disposal facilities. Therefore, this study analysed the investment and operating costs, and revenues of a municipal solid waste management facility, projected for 20 years, shared among these 19 municipalities. The economic viability analysis, has shown that, regardless of the management facility type, MSW collection and transport are the most expensive cost components, accounting for about 60% of MSW management operating costs. For an Internal Rate of Return of 0%, anaerobic digestion is 11% more expensive (in total) than using community composting. For 2040 (last year), the monthly MSW management tariffs will vary between 3.5 and 10.8 R$·inhabitant−1·month−1, depending on the municipality. So, as the unit price of biowaste treatments lowers with waste quantities, for the municipalities with large biowaste quantities, anaerobic digestion becomes recommended for its economic attractiveness. This study can serve as a model for other municipalities in Brazil and elsewhere, helping public decision makers to establish a strategy for MSW management. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) management is a pressing concern for Goiás State, Brazil. Of the state's 246 municipalities, only 16 send their waste to licensed landfills. This means that 93% of the cities in Goiás dispose of their MSW inappropriately, in dumps or unlicensed landfills. This practice poses a danger to both the environment and to public health. On this basis, the goal of this study was to survey potential landfill sites in Goiás. A geographic information system tool was used to first identify Goiás landfills and dumps and then examine them, to check whether they are located in legally restricted areas. This tool cross-references morphology, land use and occupancy, conservation of the environment, public health and population projections for 2040. It then outputs restriction-free areas that are suitable for landfill construction. The results indicate that, by 2040, Goiás will have 59,500 km 2 available for landfills, i.e., 17% of the state's total area. Conversely, 60% of the state's geographical area will be off limits for landfill construction. The most urgent need is in the Goiânia Metropolitan area, which will be producing about 40%, of 6,850 t⋅day −1 , of the MSW generated in the state by 2040. This metropolitan area will have the smallest restriction-free area for landfill construction (832 km 2 ). A total of 235 MSW final disposal facilities were identified in Goiás: 15 licensed landfills, 23 unlicensed landfills and 197 dumps. Of these, 15 are in permitted areas, 38 are in areas subject to approval and 182 are in restricted areas. These numbers highlight the need for Goiás municipalities to terminate and/or readjust landfills and unlicensed dumps and to set up new MSW management facilities that conform to the legal and environmental requirements and the expected population growth. [ABSTRACT FROM AUTHOR]

Particulate matter samples were collected in a road tunnel in Lisbon (PM 0.5 , PM 0.5–1 , PM 1–2.5 , and PM 2.5–10 ) and at two urban locations representing roadside and background stations (PM 2.5 and PM 2.5–10 ). Samples were analysed for organic and elemental carbon (OC and EC), n -alkanes, n -alkenes, hopanes, some isoprenoid compounds, and steranes. Particulate matter concentrations in the tunnel were 17–31 times higher than at roadside in the vicinity, evidencing an aerosol origin almost exclusively in fresh vehicle emissions. PM 0.5 in the tunnel comprised more than 60% and 80% of the total OC and EC mass in PM 10 , respectively. Concentrations of the different aliphatic groups of compounds in the tunnel were up to 89 times higher than at roadside and 143 times higher than at urban background. Based on the application of hopane-to-OC or hopanes-to-EC ratios obtained in the tunnel, it was found that vehicle emissions are the dominant contributor to carbonaceous particles in the city but do not represent the only source of these triterpenic compounds. Contrary to what has been observed in other studies, the Σhopane-to-EC ratios were higher in summer than in winter, suggesting that other factors (e.g. biomass burning, dust resuspension, and different fuels/engine technologies) prevail in relation to the photochemical decay of triterpenoid hydrocarbons from vehicle exhaust. [ABSTRACT FROM AUTHOR]

Abstract: An atmospheric aerosol study was performed in 2008 inside an urban road tunnel, in Lisbon, Portugal. Using a high volume impactor, the aerosol was collected into four size fractions (PM0.5, PM0.5–1, PM1 – 2.5 and PM2.5 – 10) and analysed for particle mass (PM), organic and elemental carbon (OC and EC), polycyclic aromatic hydrocarbons (PAH), soluble inorganic ions and elemental composition. Three main groups of compounds were discriminated in the tunnel aerosol: carbonaceous, soil component and vehicle mechanical wear. Measurements indicate that Cu can be a good tracer for wear emissions of road traffic. Cu levels correlate strongly with Fe, Mn, Sn and Cr, showing a highly linear constant ratio in all size ranges, suggesting a unique origin through sizes. Ratios of Cu with other elements can be used to source apportion the trace elements present in urban atmospheres, mainly on what concerns coarse aerosol particles. [Copyright &y& Elsevier]

Abstract: This study explores a large set of OC and EC measurements in PM10 and PM2.5 aerosol samples, undertaken with a long term constant analytical methodology, to evaluate the capability of the OC/EC minimum ratio to represent the ratio between the OC and EC aerosol components resulting from fossil fuel combustion (OCff/ECff). The data set covers a wide geographical area in Europe, but with a particular focus upon Portugal, Spain and the United Kingdom, and includes a great variety of sites: urban (background, kerbside and tunnel), industrial, rural and remote. The highest minimum ratios were found in samples from remote and rural sites. Urban background sites have shown spatially and temporally consistent minimum ratios, of around 1.0 for PM10 and 0.7 for PM2.5.The consistency of results has suggested that the method could be used as a tool to derive the ratio between OC and EC from fossil fuel combustion and consequently to differentiate OC from primary and secondary sources. To explore this capability, OC and EC measurements were performed in a busy roadway tunnel in central Lisbon. The OC/EC ratio, which reflected the composition of vehicle combustion emissions, was in the range of 0.3–0.4. Ratios of OC/EC in roadside increment air (roadside minus urban background) in Birmingham, UK also lie within the range 0.3–0.4. Additional measurements were performed under heavy traffic conditions at two double kerbside sites located in the centre of Lisbon and Madrid. The OC/EC minimum ratios observed at both sites were found to be between those of the tunnel and those of urban background air, suggesting that minimum values commonly obtained for this parameter in open urban atmospheres over-predict the direct emissions of OCff from road transport. Possible reasons for this discrepancy are explored. [Copyright &y& Elsevier]

Abstract: Atmospheric aerosols of four aerodynamic size ranges were collected using high volume cascade impactors in an extremely busy roadway tunnel in Lisbon (Portugal). Dust deposited on the tunnel walls and guardrails was also collected. Average particle mass concentrations in the tunnel atmosphere were more than 30times higher than in the outside urban background air, revealing its origins almost exclusively from fresh vehicle emissions. Most of the aerosol mass was concentrated in submicrometer fractions (65%), and polycyclic aromatic hydrocarbons (PAH) were even more concentrated in the finer particles with an average of 84% of total PAH present in sizes smaller than 0.49μm. The most abundant PAH were methylated phenanthrenes, fluoranthene and pyrene. About 46% of the total PAH mass was attributed to lower molecular weight compounds (two and three rings), suggesting a strong influence of diesel vehicle emissions on the production of local particulate PAH. The application of diagnostic ratios confirmed the relevance of this source of PAH in the tunnel ambient air. Deposited dust presented PAH profiles similar to the coarser aerosol size range, in agreement with the predominant origin of coarser aerosol particles from soil dust resuspension and vehicle wear products. [Copyright &y& Elsevier]

Abstract: The new compound, (bedt-ttf)[Au(cdc)2], where bedt-ttf stands for bis(3,4;3′,4′-ethylenedithio)2,2′,5,5′-tetrathiafulvalene(+) and cdc for cyanoimidodithiocarbonate(2−), was synthesised. Its structure is monoclinic, space group P21/n, with cell parameters a =6.9031(8)Å, b =21.3213(16)Å, c =7.9833(9)Å, β =91.643(6)°, V =1174.5(2)Å3 and Z =2 and consists of alternated stacking of donor and acceptor moieties along c. This compound is a semiconductor with a room temperature resistivity of 6.5×103 Ωcm and an energy gap 2Δ =0.51eV. The anisotropy and thermal dependence of the ESR signal, only due to the bedt-ttf cations, was studied in the range 4–300K. The static and EPR spin susceptibilities indicate an almost temperature independent value of 2.5×10−4 emu/mol ascribed to a three-dimensional network of antiferromagnetic interactions. [Copyright &y& Elsevier]

Abstract: The current fixed tariff remuneration for wind energy is not compatible with the deregulation of the electric power industry. The time-varying and location-dependent value of renewable energy is not acknowledged. The newly announced switchable tariff for wind energy in the Spanish electricity market provides a promising solution to compensating renewable energy within the deregulated electric power industry. The new switchable tariff provides wind generators more flexibility in operating wind generation assets. Such flexibilities provide option value in coordinating the seasonality of wind energy, demand on electric power and electricity prices movement. This paper models and valuates the flexibility on switching tariff as real compound options for wind generators. Numerical examples valuate wind generation assets under fixed tariff, spot market price taking, and yearly and monthly switchable tariffs. The optimal switching strategies are identified. The impacts of the switchable tariff on sitting criteria and values of wind generation assets are investigated. An improvement on the yearly switchable tariff is suggested to further reduce the operation risk of wind generators and fully explore the efficiency provided by competitive electricity markets. [Copyright &y& Elsevier]

The penetration of distributed generation in medium (MV) and low (LV) voltage distribution grids has been steadily increasing every year in multiple countries, thus creating new technical challenges in grid operation and motivating developments in distributed optimization for flexibility management. The traditional centralized optimal power flow (OPF) algorithm can solve technical constraints violation. However, computational efficiency, new technologies (e.g., edge computing) and control architectures (e.g., web-of-cells) are demanding for distributed approaches. This work formulates a novel distributed multi-period OPF for three-phase unbalanced grids that is essential when integrating energy storage units in operational planning (e.g., day-ahead) of LV or local energy community grids. The decentralized constrained optimization problem is solved with the alternating direction method of multipliers (ADMM) adapted for unbalanced LV grids and multi-period optimization problems. A 33-bus LV distribution grid is used as a case-study in order to define optimal battery storage scheduling along a finite time horizon that minimizes overall grid operational costs, while complying with technical constraints of the grid (e.g., voltage and current limits) and battery state-of-charge constraints. [ABSTRACT FROM AUTHOR]