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Role of Apolipoprotein E in the Hippocampus and Its Impact following Ionizing Radiation Exposure
Get PDFApolipoprotein E (ApoE) is a lipid carrier in both the peripheral and the central nervous systems (CNSs). Lipid-loaded ApoE lipoprotein particles bind to several cell surface receptors to support membrane homeostasis and brain injury repair. In the brain, ApoE is produced predominantly by astrocytes, but it is also abundantly expressed in most neurons of the CNS. In this study, we addressed the role of ApoE in the hippocampus in mice, focusing on its role in response to radiation injury. To this aim, 8-week-old, wild-type, and ApoE-deficient (ApoE−/−) female mice were acutely whole-body irradiated with 3 Gy of X-rays (0.89 Gy/min), then sacrificed 150 days post-irradiation. In addition, age-matching ApoE−/− females were chronically whole-body irradiated (20 mGy/d, cumulative dose of 3 Gy) for 150 days at the low dose-rate facility at the Institute of Environmental Sciences (IES), Rokkasho, Japan. To seek for ApoE-dependent modification during lineage progression from neural stem cells to neurons, we have evaluated the cellular composition of the dentate gyrus in unexposed and irradiated mice using stage-specific markers of adult neurogenesis. Our findings indicate that ApoE genetic inactivation markedly perturbs adult hippocampal neurogenesis in unexposed and irradiated mice. The effect of ApoE inactivation on the expression of a panel of miRNAs with an established role in hippocampal neurogenesis, as well as its transcriptional consequences in their target genes regulating neurogenic program, have also been analyzed. Our data show that the absence of ApoE−/− also influences synaptic functionality and integration by interfering with the regulation of mir-34a, mir-29b, and mir-128b, leading to the downregulation of synaptic markers PSD95 and synaptophysin mRNA. Finally, compared to acute irradiation, chronic exposure of ApoE null mice yields fewer consequences except for the increased microglia-mediated neuroinflammation. Exploring the function of ApoE in the hippocampus could have implications for developing therapeutic approaches to alleviate radiation-induced brain injury
A Simplified InSAR-Based Approach to Assess Subsidence-Induced Impacts: the Hamburg Protected Area
No full textWorld Heritage (WH) properties and heritage sites in general are exposed to the impacts of natural and man-triggered catastrophic events, which threaten their integrity and may compromise their value. The loss or deterioration of these outstanding properties has severely negative impacts on local and national communities, both because of their cultural importance, and because of their socio-economic value (https://whc.unesco.org/en/disaster-risk-reduction/). In the framework of the H2020-ARCH project a simplified approach was implemented for assessing and monitoring the subsidence hazards and the possible induced damages and short- and long-term impacts that these might cause on the buildings and other structures composing and characterising the WH sites. The InSAR data sets relating to the WH area of the Hamburg city were processed to evaluate the deformation velocity affecting each building, in order to project the Subsidence Related Intensity parameters in the short-and long-term, and thus estimate the expected damage levels through fragility curves. The results show a relatively stable situation in the area, however damage levels of a certain consistency are detectable for a long period due to the differential settlements. Furthermore, the results obtained allow us to evaluate the socio-economic impacts on the basis of some assumptions about potential losses
Simulations of RF waves propagation in hot magnetized (2H) plasma in DTT Scenario
No full textAn analytical model and numerical simulations of the propagation and absorption of radio-frequency waves in hot magnetized (2H) plasma are presented. First, an investigation of the impact of thermal effects on the dispersion relation of the waves has been conducted by expanding the hot plasma dielectric tensor to the first order in temperature. Second, starting with the realistic Ion Cyclotron Heating (ICH) antenna model designed for the Divertor Tokamak Test project, a simple 1D (1-dimensional) model of the wave propagation has been developed. The antenna's spectra have been extracted and analyzed using CST®, and the 1D wave propagation has been performed through MATLAB
Modelli e strumenti di valutazione delle CER - Identificazione e definizione di KPIs per l’analisi delle Comunità Energetiche Rinnovabili
No full textLo scopo di questo lavoro di ricerca è quello di individuare i parametri più idonei per confrontare efficacemente un insieme di Comunità Energetiche Rinnovabili (CER) da diverse prospettive, al fine di rilevare le eventuali opportunità di sviluppo e crescita, e di individuare le criticità in modo chiaro ed efficace. Tali parametri, noti in letteratura come Key Performance Indicators (KPIs), permettono di agevolare un confronto semplice ed intuitivo, mettendo in risalto da un punto di vista oggettivo le operazioni e le best practices che consentono di migliorare le performance delle comunità e permettono ai membri della comunità, stakeholders e policymakers di effettuare valutazioni sulla loro corretta gestione. L’identificazione e la definizione degli indicatori di performance ha inoltre lo scopo di mettere in luce la tipologia, le caratteristiche e i meccanismi di acquisizione dei dati necessari per la loro valutazione, nonché le modalità di elaborazione e calcolo dei KPIs, con i relativi insiemi di valori plausibili e l’interpretazione dei diversi valori ottenibili. Il processo di identificazione e definizione dei KPIs si articola su tre livelli, a scala crescente. Il primo livello consiste nell’analisi delle performance di una singola CER, con lo scopo di ottenere una panoramica completa delle prestazioni della comunità dal punto di vista energetico, economico, sociale ed ambientale. Il secondo livello riguarda il confronto tra le diverse CER con il fine di individuare le best practices e le migliori tecniche di gestione in senso assoluto attraverso modelli di calcolo semplici ed intuitivi. Infine, il terzo ed ultimo livello consiste nella valutazione delle potenzialità e dello sviluppo delle CER in relazione al proprio contesto territoriale, attraverso indicatori che quantificano la sinergia tra le comunità e le realtà locali, e gli eventuali margini di miglioramento
Measure and Monte Carlo Simulation of Thin Diamond Detector Sensitivity to 14 MeV Neutrons
No full textContinuous efforts are necessary for improving the performance and expanding the applications of single crystal diamond detectors (SCD) in medical and high-energy physics. In this paper, we present a characterization of two thin SCDs under 14 MeV neutron irradiation to assess their neutron sensitivity. Measurements were performed in current mode at the 14 MeV Frascati Neutron Generator (FNG). The detectors were realized in Schottky diode configuration at “Tor Vergata” University of Rome. The detectors showed an outstanding linearity versus neutron fluxes and a remarkably low sensitivity to this radiation, in terms of collected charge per neutron, making them suitable for diagnostics of neutron-mixed particle beams. A Monte Carlo model built with the well-known Geant4 simulation toolkit is also presented. The latter has shown not only that it can simulate with excellent accuracy the sensitivity of detectors to neutron radiation, but once the model has been calibrated against the experimental data, it is possible to estimate the thickness of the detector’s radiation-sensitive region
Explorative Approaches for Safer, Scalable, Lithium Battery Solid Electrolyte Technologies
No full textOne of the main drawbacks of commercial lithium-ion batteries is the safety issue because of the hazardous organic electrolyte compounds, especially in case of electric and/or mechanical abuse. With the aim of overcoming this limitation, two synergic approaches have been followed: i) replacement of the organic solvents with innovative, non-volatile and non-flammable fluids (ionic liquids); ii) confinement of the ionic liquid electrolytes within suitable polymeric hosts for obtaining solid-state, ionically conducting membranes. In the present work, the attention has been focused on the N1114FSI, EMIFSI and PYR14TFSI ionic liquids (combined with the LiTFSI salt), and the electro-spun PSU, PAN/PCL and PAN/PCL-OLG polymer hosts. This study presents an explorative approach for developing innovative thin-layer, solvent-free, scalable polymer electrolyte technologies from the safety and engineering points of views
Holistic Approach for Sustainable Cities and Communities: Best Practices in Living Labs
No full textThe construction sector is facing very important economic, environmental, technological, and social challenges, mainly related to climate change and extreme weather events, excess energy consumption, vulnerability of buildings and consequential damage, overpopulation, intensive urbanization, overuse of resources, social inequalities and energy poverty. Sectoral approaches that consider and value individual building performance (e.g., energy efficiency, sustainability, etc.) and not reciprocal interactions and integrations, are not functional to ensure well-being and comfort for the occupants, functionality and efficiency, performance synergy, decarbonization, and sustainable development of the city. It is well known the importance of moving from the widely prevailing paradigm of considering these dimensions in an almost unrelated way to a new paradigm that deals with a holistic view of building sustainability that integrates all relevant aspects in an efficient and implemented way. This work describes how a holistic approach and effective urban modeling, and tools can be used to ensure the implementation of that all potential synergies through technological options, economic and market instruments and measures and behavioral changes. The interactions between buildings and districts, energy communities, cities, ensuring sharing energy and data to reach a high value of self-consumption and self-sufficiency, will be analyzed. The work demonstrates the real application of the holistic approach in supporting a Renewable Energy Community in the town of Termoli in Molise, as a use case in living lab, taking in account the existing technological, governance and legal barriers
Designing Base Isolated Buildings According to the Italian Technical Code: A Benchmark for Comparison
No full textSeismic isolation is one of the most effective protection techniques used against seismic events all over the world. It can be easily used in different types of structures, especially for new constructions. While the basic concepts are almost similar in all countries, some specific rules and standards are different in each country. In this paper, the design of a base isolated building according to the Italian code is presented for comparison with other codes. The building is a seven-storey reinforced concrete condominium. Two isolation systems, composed of high damping rubber bearings and sliding devices, were designed according to the Italian Technical Code. For the seismic input, the Italian site with the maximum horizontal acceleration was chosen, with soil type C. The results can be easily compared with those obtained using other technical codes
Hydrogen Sulphide and Carbonyl Sulphide Removal from Biogas for Exploitation in High-Temperature Fuel Cells
No full textFuel cells powered by biogas for decentralised cogeneration of heat and power are an attractive alternative to combustion technologies. However, biogas contains sulfur-based compounds (H2S, COS, DMS, siloxanes), which are harmful to fuel cells. This work was carried out in the framework of the European project Waste2Watts, involving the laboratories of Politecnico di Torino, ENEA, and PSI. The aim is to design and test a flexible and cost-effective cleaning unit to remove impurities for the use of biogas in high-efficiency fuel cell systems. The focus is on small- to medium-sized farms for which deep cleaning of biogas by adsorption materials is a suitable techno-economic solution to avoid intensive gas processing treatments. The ability of commercial adsorption materials (activated carbons, metal oxides, and metal hydroxides) to remove hydrogen sulphide and carbonyl sulphide was tested under different biogas compositions (oxygen and humidity). After evaluating the results, three plant configurations were proposed to optimally utilise the potential of the sorbents. Indeed, the RGM3 sorbent has proven to be an effective solution for removing H2S and COS under humid conditions (50% RH), whilst R7H and R8C sorbents are better suited for removing H2S and COS, respectively, in dry biogas conditions. Graphical abstract: (Figure presented.
Energy Efficiency Policies for Small and Medium-Sized Enterprises: A Review
No full textThe importance of small- and medium-sized enterprises (SMEs) from economic, social, and environmental point of views and the crucial role of energy efficiency are widely recognized. However, the development of effective policies and their analysis are still challenging topics, for which research is relatively scarce. The main reasons for this are the high heterogeneity of SMEs, their low energy impact compared with energy-intensive enterprises, the lack of quantitative in-formation on the energy consumption of SMEs, and the low awareness of SMEs on energy topics. The structural paradigm change in the energy markets has underlined the importance of EE in SMEs. Several studies have been devoted to analyzing EE policies, using different methods and targets, not necessarily with a focus on SMEs or quantitative figures. This study presents a scoping review aimed at mapping the scientific literature on this topic, assessing its volume, nature, characteristics, type of evidence available, key concepts, and possible gaps. The existing contributions were systematized on three assessment levels regarding the EE policies for SMEs: general framework for their classification; comprehensive analysis of contributions providing qualitative information; in-depth analysis of evaluation studies including quantitative information. This study highlights the need for a good balance between economic and supportive mechanisms and the crucial role of energy audits. The analyzed contributions show that despite SMEs’ efforts to develop EE policies, there are still important barriers to be addressed. Moreover, there is an important lack of quantitative analyses, which are necessary for the development a harmonized policy evaluation approach. Based on a synthesis of the review findings, key learnings for the better design, implementation, and evaluation of EE policies for SMEs are provided