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Abstract This article focuses on the results obtained by the enforcement of a original greenhouse gas emissions policy, issued in recent years in several municipalities in Northern Italy. The Municipality of Reggio Emilia was one of the firsts in Italy to develop and adopt a voluntary building energy-consumption certification method called Ecoabita, aiming to promote energy efficiency in buildings over its jurisdiction. Several reasons make this project innovative: first, the certification method has been processed through and verified by a quality international agency, secondly the procedure is assisting financial-incentive policies both on mandatory (European Directive 2002/91/CE) and voluntary basis (Municipality Protocol Ecoabita), finally it allows to obtain eligible credits for avoided emissions that can be negotiated on the CO2 exchange market. With specific reference to Reggio Emilia case, acknowledged the amount of actions, that are normally scheduled in the municipality throughout a year, it has been evaluated the benefit, in terms of environmental improvement, descended from the protocol, also projecting their trend in future years up to 2020 as well, demonstrating the scheduled interventions are fundamental in sought of the achievement of the Kyoto and Copenhagen commitments. The entire procedure has been developed in accordance to the parameters given by UNFCCC for these kinds of analyses and has been recently confirmed to be one of the most accurate international accounting procedure by a survey developed by the scientific committee of the European Project LIFE-LAKS.

Patients with pure autonomic failure (PAF) and multiple system atrophy (MSA) may complain of feeling light-headed after alcohol ingestion particularly on assumption of the upright posture. The reasons for this have not been investigated. We therefore studied the effects of oral alcohol (40% vodka in sugar-free orange juice) and placebo (juice only) on the systemic and regional (including superior mesenteric artery, SMA) blood flow in nine patients with PAF and six patients with MSA. After alcohol, there was a fall in supine blood pressure (BP) and vasodilatation in the SMA but no change in cardiac output, or forearm muscle and cutaneous blood flow in either PAF or MSA; BP fell further during head-up tilt with no changes in levels of plasma catecholamines. After placebo, there were no changes while supine. We conclude that alcohol lowers supine BP and dilates the SMA with no change in muscle or cutaneous blood flow. Alcohol also enhances the fall in BP during head-up tilt. This may explain the symptoms experienced by PAF and MSA patients after alcohol.

Abstract Probability density functions (PDFs) are normally used to describe wind speed distribution for the proper selection of wind turbines in a given location. The identification of a suitable PDF is fundamental for accurately assessing the wind energy potential and designing the wind farms. To achieve this objective, the use of a mixture of two truncated normal distributions (MTTND), defined for v ≥ 0 and obtained by linearly combining two normal distributions with different means and variances, is proposed in this work for the representation of the wind speed PDF. The distribution is a function of five parameters, does not require a high computational burden and allows the representation of wind calm hours (v = 0). The use of the MTTND allows an accurate estimation to be obtained of the experimental discrete distribution of the probability density and cumulative probability, and the characteristic statistical quantities used to estimate the available energy and the performance indicators in the selection of both the site and wind turbine. The validity of the use of the MTTND was verified by comparison with the most widespread PDFs in the scientific literature: Weibull, Rayleigh, lognormal, gamma, inverse Gaussian and Burr. This comparison was developed using experimental wind speed data relating to five Italian locations and a location in Colorado (USA) belonging to the National Renewable Energy Laboratory. For each location, the parameters of each PDF were obtained with the least squares non-linear regression method. The results of the comparisons, in terms of the coefficient of determination R2 and root mean square error (RMSE) for goodness of fit and in terms of relative error in the calculation of the statistical quantities, show that the use of the MTTND gives rise to greater accuracy than a conventional wind speed PDF.

Abstract Reaching universal access to electricity by 2030 requires a massive deployment of mini-grids in rural areas of developing countries. Among the many challenges hindering this process, there are the high uncertainties in assessing demand patterns in rural communities, the costs of field survey campaigns, and the absence of ample and reliable datasets coming from existing projects. This paper tries to address these issues by presenting and discussing a database of load profiles from sixty-one off-grid mini-grids from developing countries worldwide, gathered from the literature, private developers and fieldworks, and reported with technical, socio-economic and geographical characterization factors. A clustering procedure led to the identification of five archetypal load profile clusters, which are presented and analyzed together with their load duration curves. Subsequently, the distribution among the clusters of the various characterization factors selected is studied. The proposed approach allows to widen the range of load profiles usually considered, and to seek correlations between the load profile shapes, the peak power and average energy consumption per connection, the number of customers, the age of measurement, geographical position, operator model, type of tariff and generation technologies present. This work establishes a first step in the creation of a shared database for load profiles of rural mini-grids, helping to overcome the lack of available data and difficulties of demand assessment, proposing original insights for researchers to understand load patterns, and contributing to reduce risks and uncertainties for mini-grid developers.

Abstract In vivo NMR techniques and substrates selectively enriched with 13 C were used to follow the step-by-step metabolism of glucose and xylose, on their own or as mixed substrates in the ratio as they occur in hydrolysates from hemicellulose. The organism used was a newly isolated strain of Klebsiella planticola isolated from soil where maize has been cultivated for 30 years. Results suggest that glucose is converted to pyruvate via the Embden-Meyerhof pathway and then to lactate and ethanol. No evidence of 2,3-butandiol or formate metabolism was observed. This organism had a higher rate of uptake of xylose than previously studied microorganisms, resulting in ethanol, lactate, acetate succinate and formate as end products. Xylose metabolism in K. planticola G11, unlike that reported for many other organisms, was not inhibited by glucose. The addition of glucose, after 2 h of xylose fermentation, did not change the rate of xylose metabolism.

AbstractEcologists are increasingly aware of the importance of environmental variability in natural systems. Climate change is affecting both the mean and the variability in weather and, in particular, the effect of changes in variability is poorly understood. Organisms are subject to selection imposed by both the mean and the range of environmental variation experienced by their ancestors. Changes in the variability in a critical environmental factor may therefore have consequences for vital rates and population dynamics. Here, we examine ≥90‐year trends in different components of climate (precipitation mean and coefficient of variation (CV); temperature mean, seasonal amplitude and residual variance) and consider the effects of these components on survival and recruitment in a population of Eurasian beavers (n = 242) over 13 recent years. Within climatic data, no trends in precipitation were detected, but trends in all components of temperature were observed, with mean and residual variance increasing and seasonal amplitude decreasing over time. A higher survival rate was linked (in order of influence based on Akaike weights) to lower precipitation CV (kits, juveniles and dominant adults), lower residual variance of temperature (dominant adults) and lower mean precipitation (kits and juveniles). No significant effects were found on the survival of nondominant adults, although the sample size for this category was low. Greater recruitment was linked (in order of influence) to higher seasonal amplitude of temperature, lower mean precipitation, lower residual variance in temperature and higher precipitation CV. Both climate means and variance, thus proved significant to population dynamics; although, overall, components describing variance were more influential than those describing mean values. That environmental variation proves significant to a generalist, wide‐ranging species, at the slow end of the slow‐fast continuum of life histories, has broad implications for population regulation and the evolution of life histories.

Urea is the most common nitrogen (N) fertilizer in agriculture, due to its cheaper price and high N content. Although the reciprocal influence between NO3- and NH4+ nutrition are well known, urea (U) interactions with these N-inorganic forms are poorly studied. Here, the responses of two tomato genotypes to ammonium nitrate (AN), U alone or in combination were investigated. Significant differences in root and shoot biomass between genotypes were observed. Under AN+U supply, Linosa showed higher biomass compared to UC82, exhibiting also higher values for many root architectural traits. Linosa showed higher Nitrogen Uptake (NUpE) and Utilization Efficiency (NUtE) compared to UC82, under AN+U nutrition. Interestingly, Linosa exhibited also a significantly higher DUR3 transcript abundance. These results underline the beneficial effect of AN+U nutrition, highlighting new molecular and physiological strategies for selecting crops that can be used for more sustainable agriculture. The data suggest that translocation and utilization (NUtE) might be a more important component of NUE than uptake (NUpE) in tomato. Genetic variation could be a source for useful NUE traits in tomato; further experiments are needed to dissect the NUtE components that confer a higher ability to utilize N in Linosa.

Abstract Electricity dispatch is a difficult optimisation problem that aims at minimising total fuel cost while satisfying system power demand and certain thermal unit constraints. Modelling valve point effects, multiple fuel options or transmission losses brings non-convexity and non-smoothness into the mathematical models. This paper proposes mathematical programming-based models for valve point effects, multiple fuel options and transmission loss problems respectively. Mathematical programming leads to robust and rigorous optimisation methods for these problems. The applicability of the proposed methods is demonstrated through a number of case studies. For all the case studies, the corresponding methods identify power schedules at least as good as or better than the best known in literature.