1,513 research outputs found
Optimal stimulation protocol in a bistable synaptic consolidation model
Consolidation of synaptic changes in response to neural activity is thought
to be fundamental for memory maintenance over a timescale of hours. In
experiments, synaptic consolidation can be induced by repeatedly stimulating
presynaptic neurons. However, the effectiveness of such protocols depends
crucially on the repetition frequency of the stimulations and the mechanisms
that cause this complex dependence are unknown. Here we propose a simple
mathematical model that allows us to systematically study the interaction
between the stimulation protocol and synaptic consolidation. We show the
existence of optimal stimulation protocols for our model and, similarly to LTP
experiments, the repetition frequency of the stimulation plays a crucial role
in achieving consolidation. Our results show that the complex dependence of LTP
on the stimulation frequency emerges naturally from a model which satisfies
only minimal bistability requirements.Comment: 23 pages, 6 figure
Dataset for assessing the economic performance of a residential pv plant. The analysis of a new policy proposal
This data article aims at providing a data description about the manuscript entitled âThe post COVID-19 green recovery in practice: assessing the profitability of a policy proposal on residential photovoltaic plantsâ. The definition of a business plan is a complex decision because the choice of the input data significantly influences the economic assessment of a project. An Excel file is used to construct an economic model based on the Discounted Cash Flow (DCF) methodology using Net Present Value (NPV) as an indicator. The choice of input data is defined by literature analysis, and policy proposals are identified by the Revival Decree adopted by Italian Government to contrast human and economic shock effected by COVID-19. The aggregation of these data enabled us to obtain both baseline and alternative scenarios to define if the realization of a residential photovoltaic (PV) plant is economically feasible. Similar data can be obtained for other countries according to the policy actions adopted, and this work can be easily replicated in different geographical contexts and considering varying categories of stakeholders (e.g., consumers, which are called upon to implement a green transition)
Sustainable food waste management in supermarkets
ood waste represents a significant burden to waste management systems, exacerbating food insecurity and contributing to global pollution, climate change, and biodiversity loss. Supermarkets bear partial responsibility for food waste, yet their sustainability efforts could also contribute to a solution. The present work aims at evaluating a sustainable approach to food waste management within supermarkets. To this end, we conducted a multi-criteria analysis, incorporating the perspectives of academic experts and 505 Italian consumers. Experts deemed residual value apps the most sustainable solution for food waste management in supermarkets, while also emphasising the influence of price and brand image. The consumer analysis corroborated these results. Specifically, consumers expressed a willingness to pay 36 % less for a bag of goods set to expire within 2â3 days, which increased to 60 % for goods set to expire within 24 h. The findings point to opportunities for mutual benefit between consumers and suppliers when food waste is effectively managed in store, thereby highlighting the need for further, product-focused research
A comparison of environmental and energetic performance of European countries: A sustainability index
Recently, European countries agreed on a new 2030-pact establishing challenging levels for a set of climate and energy indexes in order to achieve a more competitive, safe and sustainable energy system. In order to evaluate current sustainability performances of European countries from the environmental and energetic perspectives, this research proposes a Multi-Criteria Decision Analysis (MCDA) that, starting from both Eurostat data and the Analytic Hierarchy Process (AHP), allows a direct comparison of nations. To this aim, multiple indexes are taken into account (e.g. Greenhouse gas (GHG) emissions, Government expenditures for environmental protection, Recycled and reused waste from electric and electronic equipments (WEEEs), Recycled and reused waste from end-of-life vehicles (ELVs), Recycled materials from Municipal Solid Wastes (MSWs), Share of renewable energy (RE) in electricity, Share of RE in transport, Share of RE in heating and cooling and Primary energy consumption). This assessment model provides a sustainability value for each European country and the related ranking with the European average. Results show as, even nowadays, twelve out of twenty-eight European countries have a value greater than the European average in 2013. Top four nations (Sweden, Denmark, Finland and Austria) have high indexes of sustainability and Sweden is the best country from both the environmental and energetic perspectives
Machine Learning approaches for the design of biomechanically compatible bone tissue engineering scaffolds
Triply-Periodic Minimal Surfaces (TPMS) analytical formulation does not provide a direct correlation between the input parameters (analytical) and the mechanical and morphological properties of the structure. In this work, we created a dataset with more than one thousand TPMS scaffolds for the training of Machine Learning (ML) models able to find such correlation. Finite Element Modeling and image analysis have been used to characterize the scaffolds. In particular, we trained three different ML models, exploring both a linear and non-linear approach, to select the features able to predict the input parameters. Furthermore, the features used for the prediction can be selected in three different modes: i) fully automatic, through a greedy algorithm, ii) arbitrarily, by the user and iii) in a combination of the two above methods: i.e. partially automatic and partially through a user-selection. The latter, coupled with the non-linear ML model, exhibits a median error less than 3% and a determination coefficient higher than 0.89 for each of the selected features, and all of them are accessible during the design phase. This approach has been applied to the design of a hydroxyapatite TPMS scaffolds with prescribed properties obtained from a real trabecular-like hydroxyapatite scaffold. The obtained results demonstrate that the ML model can effectively design a TPMS scaffold with prescribed features on the basis of biomechanical, mechanobiology and technological constraints
Circular solar: Evaluating the profitability of a photovoltaic panel recycling plant
Photovoltaic (PV) panels have a crucial role in coping with the global warming mitigation and the energetic crisis currently affecting the European Community. However, from the circular perspective of end-of-life (EoL) management, there are still big issues to be solved in order to recover materials from this kind of e-wastes. Because of several reasons (e.g. type of embedded materials, illegal shipments, location of manufacturers) EoL businesses do not have the interest in approaching them. This poses a significant environmental concern in terms of their management. This work wants to assess the profitability of a specific PV module recycling plant, by evaluating several market contexts in which multiple scenarios of material price, investment and process costs will be considered. The results for a 3000 tonnes plant show that profitability is not verified in the absence of an avoided landfill cost. Instead, when a value of 200 euro/tonnes is applied, the net present value is positive in 35.2% of the scenarios and at 87.6% when a value of 350 euro/tonnes is considered. The policy choice of this value requires linking the PV module disposal fee to the circular benefits associated with its recovery
Oscillating Positive Expiratory Pressure on Respiratory Resistance in Chronic Obstructive Pulmonary Disease With a Small Amount of Secretion: A Randomized Clinical Trial
Abstract: This study aims to evaluate the acute effects of an oscillating positive expiratory pressure device (flutter) on airways resistance in patients with chronic obstructive pulmonary disease (COPD). Randomized crossover study: 15 COPD outpatients from Asthma LabâRoyal Brompton Hospital underwent spirometry, impulse oscillometry (IOS) for respiratory resistance (R) and reactance (X), and fraction exhaled nitric oxide (FeNO) measures. Thirty minutes of flutter exercises: a âflutter-shamâ procedure was used as a control, and airway responses after a short-acting bronchodilator were also assessed. Respiratory system resistance (R): in COPD patients an increase in X5insp (-0.21 to -0.33 kPa/L/s) and Fres (24.95 to 26.16 Hz) occurred immediately after flutter exercises without bronchodilator. Following 20 min of rest, a decrease in the R5, [DELTA]R5, R20, X5, and Ax was observed, with R5, R20, and X5 values lower than baseline, with a moderate effect size; there were no changes in FeNO levels or spirometry. The use of flutter can decrease the respiratory system resistance and reactance and expiratory flow limitation in stable COPD patients with small amounts of secretions
Comparing home and parcel lockersâ delivery systems: a math-heuristic approach
E-commerce is a continuously growing sector worldwide, with important repercussions on the delivery system in urban area and especially in the Business to Consumer (B2C) sector. The delivery of a package to a consumer's address involves not only high costs for couriers (greater number of kilometres travelled), but also increased congestion and greater environmental pollution (greater volume of pollutants released into the air). To rationalize deliveries in urban areas the use of collection points, equipped with lockers, to store the goods that users have ordered has been considered in literature. This work compares two alternative delivery options: deliveries to the consumer's home versus to Lockers. To make this comparison we used a cluster first route second math-heuristic approach. In the clustering phase, we experimented a new clustering function, while the routing phase consists in solving an instance of the Traveling Salesman Problem for each generated cluster. Finally, we applied the math-heuristic to a real case (the Italian municipality of Dolo near Venice) and compared the two delivery alternatives. We evaluate the performance considering two different fleets of vehicles, with small and medium capacity. In addition, since additional trips might be performed by consumers to pick up parcels at Lockers, a sensitivity analysis was carried out to analyse the sustainability of the proposed city logistics scheme
Gluten contamination of canned and dry grain-free commercial pet foods determined by HPLC-HRMS
The aim was to determine the absence of gluten in pet food samples marked as âgrain-freeâ and âgluten-freeâ diets, to assess the reliability of manufacturer labelling of such products. A total of 15 diets labelled as grain- or gluten-free and 2 commercial diets containing wheat were sampled. An analytical procedure using high-pressure liquid chromatography coupled with mass spectrometry with high power of resolution was developed and applied to determine specific markers of wheat gluten. The results are expressed as mg of wheat flour type â00â present in 1âg of feed. The quantification limit (LOQ) obtained in the flour for ion m/z 894.5043, zâ=â2, is 4âmg of flour per gram. In 14 out of the 15 samples from a grain- or gluten-free diet the quantifier ion signal wasâ<âLOQ, while in 1 out of the 15 samples 10âmg of flour/g feed were measured.Highlights Adverse reaction to gluten in dogs have been documented in certain breeds Gluten is tricky to detect and measure in pet food Contamination of gluten in pet food samples marked as âgrain-freeâ and âgluten-freeâ diets An analytical procedure was developed using HPLC coupled with HRM
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