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SemSimp: A Parametric Method for Evaluating the Semantic Similarity of Digital Resources
No full textSemSimp is a parametric method for evaluating the semantic similarity of digital resources that is based on the notion of information content. It exploits a weighted reference ontology of concepts and requires resources to be semantically annotated, each by means of a set of concepts from the ontology. Specifically, the weights of the concepts can be calculated either by considering the available annotations or only the structure of the ontology. SemSimp was evaluated against six representative semantic similarity methods proposed in the literature. Experiments were run on a large real-world dataset based on the Association for Computing Machinery (ACM) digital library, including both a statistical analysis and an expert judgment assessment. The main result shows that the SemSimp annotation frequency configuration, when combined with the geometric average normalization factor, outperforms the other methods
Anthropogenic litter in a Mediterranean coastal wetland: A heterogeneous spatial pattern of historical deposition
No full textCoastal wetlands represent areas that can testify historical accumulation of litter. We analyzed the anthropogenic litter deposited on the channel bottom of a coastal wetland area that experienced water stress due to extreme summer dryness after about 20 years. We hypothesize that the litter accumulated in the different areas over the years reflects the different social user categories (i.e., fishermen, beach users, hunters) and exposure to meteo-marine events. Our findings highlight that historically accumulated litter is composed of plastics (78.8 %), clothes (8.9 %), and glass (4.9 %). Moreover, litter concentration averages 53.6 items/ha in the 8 sectors. The most found categories were common household items (25.4 %), diverse (professional and consumer) items (24.2 %), and food and beverages packaging (21.4 %). Finally, litter diversity indices and the Detrended Correspondence Analysis showed sector and litter type similarities. We reported for the first time the presence of litter accumulated for 20 years testifying non-more occurring recreational activities
Preliminary thermo-mechanical assessment of the Top Cap region of the Water-Cooled Lead-Ceramic Breeder Breeding Blanket alternative concept
Get PDFThe Water-Cooled Lead Lithium (WCLL) and the Helium-Cooled Pebble Bed (HCPB) Breeding Blanket (BB) concepts are the two candidates currently poised to be chosen as the driver blanket for the EU DEMO reactor. Nevertheless, new variants are emerging with the aim of overtaking the potential showstoppers arisen during the WCLL and HCPB BB pre-conceptual design phase. Then, an intense campaign of exploratory studies has been launched in EU to investigate the potential performances of such alternative concepts. Among them, the Water-Cooled Lead-Ceramic Breeder (WLCB) BB concept is one of the most promising. It has been conceived as a trade-off (i.e. an hybrid concept) between WCLL and HCPB BB concepts, trying to take and integrating the best features of both. Since in the reference WCLL geometric layout the Top Cap (TC) region was identified as particularly critical from thermal and mechanical standpoints, so requiring specific design studies, also in the WLCB conceptual design activities a dedicated campaign of analysis has been necessary to preliminarily size the TC region components. Hence, in this paper, the preliminary thermo-mechanical assessment of the TC region of the WLCB BB alternative concept is presented. First, an initial geometric layout has been set-up on the basis of the main features of the reference WCLL BB TC region. Then, thermal analysis under nominal conditions has been performed and the results have shown that modifications were necessary to ensure the compliance with the thermal requirements of the structural material. Finally, once obtained an acceptable geometric layout, mechanical analyses were carried out in order to verify the fulfilment of the RCC-MRx structural design criteria, also considering an off-normal load case. The results showed that this variant is very promising in terms of structural behaviour, whereas further design iterations are necessary to lower the temperature of the breeder zone
Intraneural Device for Electrostimulation of Vagus Nerve in Rats: A Feasibility Study for Modulating Glucose Tolerance
No full textObjectives: This study introduces EMPATIC (Electro-Modulation of PAncreaTic Islet Cells), a miniaturized intraneural device designed for transversal insertion into small nerves with a mean diameter of 400 μm. EMPATIC aims to modulate glucose tolerance through intraneural vagus nerve stimulation (VNS) in rats. Materials and Methods: EMPATIC design was optimized to fit into the cervical vagus nerve of rats and was developd through thin film microtechnologies. We evaluated the efficacy of the stimulation protocol (200 μA for 10 μs at 1 Hz) on glucose tolerance after intraperitoneal injection of glucose in three rat groups: control (no implant), sham (EMPATIC implant, no stimulation), and VNS (EMPATIC implant with stimulation). Results: EMPATIC treatment in the VNS group significantly affected glucose tolerance tests compared with control and sham groups. The glucose tolerance test's area under the curve was 17,652 ± 913 mg∗min/dL in the control group, 16,929 ± 765 mg∗min/dL in the sham group, and reduced to 12,749 ± 1,075 mg∗min/dL in the stimulated group with statistical significance (p < 0.05 stimulated vs sham group, p < 0.05 stimulated vs control group). Blood glucose and insulin levels were measured, also under fasting conditions, for control and VNS groups, producing no statistically significant difference. Conclusions: EMPATIC treatment is effective in hyperglycemic conditions after glucose intake. No significant effects were observed when VNS was applied under fasting conditions. This study indicated the suitability of applying thin-film intrafascicular electrodes for transversal insertion into small nerves (mean diameter of 400 μm), which, to the best of our knowledge, represents an advancement over the state of the art. It also establishes the feasibility of investigating neural pathways related to glucose homeostasis using invasive intraneural electrodes in the right cervical vagus nerve of rats
Seismic Performance of Steel Buildings with Eccentrically Braced Frame Systems with Different Configurations
No full textAlthough eccentrically braced frames (EBFs) can be used with different configurations according to architectural requirements, it has not yet been indicated which configuration has a better seismic performance; therefore, this paper presents an analytical study focused on evaluating the seismic behavior of various steel buildings with EBF systems, factoring in different configurations. Furthermore, the objective is to compare the performances of EBF systems with one another, to learn more about their structural efficiency. The results obtained indicate that seismic response, in terms of peak interstory drifts, depends on the structural period and hysteretic behavior of the links, because high levels of plastic rotation increase lateral displacement. In addition, it was observed that maximum drift demands are concentrated in the lower floors where the links exhibit inelastic behavior, while the level of interstory drift decreases as height increases
Assessment of the sensitivity of model responses to urban emission changes in support of emission reduction strategies
No full textThe sensitivity of air quality model responses to modifications in input data (e.g. emissions, meteorology and boundary conditions) or model configurations is recognized as an important issue for air quality modelling applications in support of air quality plans. In the framework of FAIRMODE (Forum of Air Quality Modelling in Europe, https://fairmode.jrc.ec.europa.eu/) a dedicated air quality modelling exercise has been designed to address this issue. The main goal was to evaluate the magnitude and variability of air quality model responses when studying emission scenarios/projections by assessing the changes of model output in response to emission changes. This work is based on several air quality models that are used to support model users and developers, and, consequently, policy makers. We present the FAIRMODE exercise and the participating models, and provide an analysis of the variability of O3 and PM concentrations due to emission reduction scenarios. The key novel feature, in comparison with other exercises, is that emission reduction strategies in the present work are applied and evaluated at urban scale over a large number of cities using new indicators such as the absolute potential, the relative potential and the absolute potency. The results show that there is a larger variability of concentration changes between models, when the emission reduction scenarios are applied, than for their respective baseline absolute concentrations. For ozone, the variability between models of absolute baseline concentrations is below 10%, while the variability of concentration changes (when emissions are similarly perturbed) exceeds, in some instances 100% or higher during episodes. Combined emission reductions are usually more efficient than the sum of single precursor emission reductions both for O3 and PM. In particular for ozone, model responses, in terms of linearity and additivity, show a clear impact of non-linear chemistry processes. This analysis gives an insight into the impact of model’ sensitivity to emission reductions that may be considered when designing air quality plans and paves the way of more in-depth analysis to disentangle the role of emissions from model formulation for present and future air quality assessments
Solar heat for the decarbonization of chemical industry: dehydrogenation of ethylbenzene to styrene driven by a concentrating solar power plant with molten salts as heat transfer fluids
Get PDFThe dehydrogenation of ethylbenzene to styrene was used as a model of an energy intensive endothermic process to assess the economic sustainability of the utilization of solar heat from a concentrating solar power (CSP) plant to decarbonize an industrial chemical processes. To this purpose a process configuration compatible with the hybridization with a CSP plant using a binary mixture NaNO3/KNO3, 60/40 w/w as heat transfer fluid (HTF) was selected. The adopted chemical reactor is a shell and tube bundle converter with 30000 tubes of 6 m length and 0.025 m inside diameter that approaches isothermal regime with a productivity of 103 kT/year of styrene if a flowrate of 200 kg/s of molten salt at 560 °C are fed to the shell. The residual enthalpy of the HTF leaving the dehydrogenation reactor was further injected in the process by vaporizing and pre-heating ethylbenzene and dilution water. A cash flow analysis of the hybridized plant was performed considering solar field of increasing size so that the required solar power of 45 MW can be supplied for longer period of the year. We found that a CSP plant of 70 collectors can decrease CO2 emissions of about 50 % with a rate of return on investment (ROROI) of 9.1 % for the solar field of the hybridized plant and can grant 410 k€/year of economic benefit arising from the methane and the lower emissions of CO2. This study demonstrates that solar heat can be used to decarbonize energy intensive endothermic chemical processes without economic penalty for the plant profitability
A Novel LIBS Sensor for Sample Examinations on a Crime Scene
No full textIn this work, we present a compact LIBS sensor developed for characterization of samples on a crime scene following requirements of law enforcement agencies involved in the project. The sensor operates both in a tabletop mode, for aside measurements of swabbed materials or taken fragments, and in handheld mode where the sensor head is pointed directly on targets at the scene. The sensor head is connected via an umbilical to an instrument box that could be battery-powered and contains also a color camera for sample visualization, illumination LEDs, and pointing system for placing the target in focus. Here we describe the sensor’s architecture and functionalities, the optimization of the acquisition parameters, and the results of some LIBS measurements. On nano-plotted traces at silica wafer and in optimized conditions, for most of the elements the detection limits, in term of the absolute element masses, were found to be below 10 picograms. We also show results obtained on some representative materials, like fingerprints, swabbed soil and gunshot residue, varnishes on metal, and coated plastics. The last, solid samples were used to evaluate the depth profiling capabilities of the instrument, where the recognition of all four car paint layers was achieved
Energy Efficiency of the Office Buildings in Italy: Insights for the European Taxonomy
No full textSustainable investments have led the Italian real estate market over recent years. Large enterprises invest in renovating their building stocks to optimize costs, respond to institutional pressures, and enhance their Environmental, Social, and Governance (ESG) scores. The ESG criteria orient the preferences of today's investors by measuring a company's sustainability and profitability; however, the ESG rating systems lack transparency, exposing investors to misleading sustainable initiatives (greenwashing) and risks of financial losses. The EU Taxonomy for Sustainable Activities (EU Regulation 2020/852) defines technical thresholds for sustainability that support investors in making informed decisions. In the building sector, the Taxonomy distinguishes (i) new building construction and (ii) retrofitting existing buildings; the latter is sustainable if it reduces the existing building's primary energy use by 30% compared to ante-opera or follows the retrofitting guidelines established by the EU directive 2010/31. This work aims to estimate the potential for energy savings and CO2 reduction of the Italian office building stock according to the Taxonomy guidelines. The Energy Efficiency Directive 2012/27/EU (EED) establishes a legislative framework for achieving the European energy efficiency targets. Article 8 of the EED introduced the obligation for large enterprises to submit an energy audit of their production sites every four years, starting from December 2015, and the Italian National Agency for New Technologies, Energy, and the Sustainable Economic Development (ENEA) collects and reviews such energy audits. This study analyzes the energy audits of office buildings submitted by large enterprises in the insurance and banking sectors last year. The database associates the technical features of each building with the main characteristics of its location (e.g., the climate and urban landscape) and energy use. Data show the benefits of retrofitting office building portfolios following the Taxonomy, showing a reduction of energy use and CO2 emissions up to 20% from the current state. Electrification of heating loads is particularly effective in cold climates. At the same time, intense reconstruction produces the highest benefits, but it needs careful resource allocation, driven by cost-benefit analysis
Lab-on-Chip Label-Free Sensing System for Electroporation Based on Time-Lapse Microscopy
No full textElectroporation has been shown to have considerable potential in biological research and clinical applications. This technique permits the opening of reversible or irreversible nanometric pores in cellular membranes by the application of a high-intensity electric field characterized by extremely short duration (i.e., microseconds, nanoseconds down to tens of picoseconds). Recently, also thanks to the spreading use of lab-on-chip, it was discovered that applying a high electric field to single cells can cause them to contract and generate blebs. Even though these effects are known in the literature, their correlation with the electroporation phenomenon is still unclear. For this reason, in this work, we present a reliable, low-cost sensing system based on a lab-on-chip platform with transferred laser-induced graphene (LIG) electrodes to study electroporation by bright-field and fluorescence time-lapse microscopy. The acquired video was then used to extrapolate the calcium intake due to electroporation, cell contractility, and morphology over time. The two abovementioned side effects were finally correlated with electroporation and used to estimate its efficacy on single cells, exploiting calcium intake information as the ground truth. The proposed sensing system could be used to predict the electroporation phenomenon easily and even in a label-free modality, using exclusively the morphological variations induced in the single cells